| 1. |
- Lozano, Rafael, et al.
(författare)
-
Measuring progress from 1990 to 2017 and projecting attainment to 2030 of the health-related Sustainable Development Goals for 195 countries and territories: a systematic analysis for the Global Burden of Disease Study 2017
- 2018
-
Ingår i: The Lancet. - : Elsevier. - 1474-547X .- 0140-6736. ; 392:10159, s. 2091-2138
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Efforts to establish the 2015 baseline and monitor early implementation of the UN Sustainable Development Goals (SDGs) highlight both great potential for and threats to improving health by 2030. To fully deliver on the SDG aim of “leaving no one behind”, it is increasingly important to examine the health-related SDGs beyond national-level estimates. As part of the Global Burden of Diseases, Injuries, and Risk Factors Study 2017 (GBD 2017), we measured progress on 41 of 52 health-related SDG indicators and estimated the health-related SDG index for 195 countries and territories for the period 1990–2017, projected indicators to 2030, and analysed global attainment. Methods: We measured progress on 41 health-related SDG indicators from 1990 to 2017, an increase of four indicators since GBD 2016 (new indicators were health worker density, sexual violence by non-intimate partners, population census status, and prevalence of physical and sexual violence [reported separately]). We also improved the measurement of several previously reported indicators. We constructed national-level estimates and, for a subset of health-related SDGs, examined indicator-level differences by sex and Socio-demographic Index (SDI) quintile. We also did subnational assessments of performance for selected countries. To construct the health-related SDG index, we transformed the value for each indicator on a scale of 0–100, with 0 as the 2·5th percentile and 100 as the 97·5th percentile of 1000 draws calculated from 1990 to 2030, and took the geometric mean of the scaled indicators by target. To generate projections through 2030, we used a forecasting framework that drew estimates from the broader GBD study and used weighted averages of indicator-specific and country-specific annualised rates of change from 1990 to 2017 to inform future estimates. We assessed attainment of indicators with defined targets in two ways: first, using mean values projected for 2030, and then using the probability of attainment in 2030 calculated from 1000 draws. We also did a global attainment analysis of the feasibility of attaining SDG targets on the basis of past trends. Using 2015 global averages of indicators with defined SDG targets, we calculated the global annualised rates of change required from 2015 to 2030 to meet these targets, and then identified in what percentiles the required global annualised rates of change fell in the distribution of country-level rates of change from 1990 to 2015. We took the mean of these global percentile values across indicators and applied the past rate of change at this mean global percentile to all health-related SDG indicators, irrespective of target definition, to estimate the equivalent 2030 global average value and percentage change from 2015 to 2030 for each indicator. Findings: The global median health-related SDG index in 2017 was 59·4 (IQR 35·4–67·3), ranging from a low of 11·6 (95% uncertainty interval 9·6–14·0) to a high of 84·9 (83·1–86·7). SDG index values in countries assessed at the subnational level varied substantially, particularly in China and India, although scores in Japan and the UK were more homogeneous. Indicators also varied by SDI quintile and sex, with males having worse outcomes than females for non-communicable disease (NCD) mortality, alcohol use, and smoking, among others. Most countries were projected to have a higher health-related SDG index in 2030 than in 2017, while country-level probabilities of attainment by 2030 varied widely by indicator. Under-5 mortality, neonatal mortality, maternal mortality ratio, and malaria indicators had the most countries with at least 95% probability of target attainment. Other indicators, including NCD mortality and suicide mortality, had no countries projected to meet corresponding SDG targets on the basis of projected mean values for 2030 but showed some probability of attainment by 2030. For some indicators, including child malnutrition, several infectious diseases, and most violence measures, the annualised rates of change required to meet SDG targets far exceeded the pace of progress achieved by any country in the recent past. We found that applying the mean global annualised rate of change to indicators without defined targets would equate to about 19% and 22% reductions in global smoking and alcohol consumption, respectively; a 47% decline in adolescent birth rates; and a more than 85% increase in health worker density per 1000 population by 2030. Interpretation: The GBD study offers a unique, robust platform for monitoring the health-related SDGs across demographic and geographic dimensions. Our findings underscore the importance of increased collection and analysis of disaggregated data and highlight where more deliberate design or targeting of interventions could accelerate progress in attaining the SDGs. Current projections show that many health-related SDG indicators, NCDs, NCD-related risks, and violence-related indicators will require a concerted shift away from what might have driven past gains—curative interventions in the case of NCDs—towards multisectoral, prevention-oriented policy action and investments to achieve SDG aims. Notably, several targets, if they are to be met by 2030, demand a pace of progress that no country has achieved in the recent past. The future is fundamentally uncertain, and no model can fully predict what breakthroughs or events might alter the course of the SDGs. What is clear is that our actions—or inaction—today will ultimately dictate how close the world, collectively, can get to leaving no one behind by 2030.
|
|
| 2. |
- Murray, Christopher J. L., et al.
(författare)
-
Population and fertility by age and sex for 195 countries and territories, 1950–2017: a systematic analysis for the Global Burden of Disease Study 2017
- 2018
-
Ingår i: The Lancet. - 1474-547X .- 0140-6736. ; 392:10159, s. 1995-2051
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Population estimates underpin demographic and epidemiological research and are used to track progress on numerous international indicators of health and development. To date, internationally available estimates of population and fertility, although useful, have not been produced with transparent and replicable methods and do not use standardised estimates of mortality. We present single-calendar year and single-year of age estimates of fertility and population by sex with standardised and replicable methods. Methods: We estimated population in 195 locations by single year of age and single calendar year from 1950 to 2017 with standardised and replicable methods. We based the estimates on the demographic balancing equation, with inputs of fertility, mortality, population, and migration data. Fertility data came from 7817 location-years of vital registration data, 429 surveys reporting complete birth histories, and 977 surveys and censuses reporting summary birth histories. We estimated age-specific fertility rates (ASFRs; the annual number of livebirths to women of a specified age group per 1000 women in that age group) by use of spatiotemporal Gaussian process regression and used the ASFRs to estimate total fertility rates (TFRs; the average number of children a woman would bear if she survived through the end of the reproductive age span [age 10–54 years] and experienced at each age a particular set of ASFRs observed in the year of interest). Because of sparse data, fertility at ages 10–14 years and 50–54 years was estimated from data on fertility in women aged 15–19 years and 45–49 years, through use of linear regression. Age-specific mortality data came from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017 estimates. Data on population came from 1257 censuses and 761 population registry location-years and were adjusted for underenumeration and age misreporting with standard demographic methods. Migration was estimated with the GBD Bayesian demographic balancing model, after incorporating information about refugee migration into the model prior. Final population estimates used the cohort-component method of population projection, with inputs of fertility, mortality, and migration data. Population uncertainty was estimated by use of out-of-sample predictive validity testing. With these data, we estimated the trends in population by age and sex and in fertility by age between 1950 and 2017 in 195 countries and territories. Findings: From 1950 to 2017, TFRs decreased by 49·4% (95% uncertainty interval [UI] 46·4–52·0). The TFR decreased from 4·7 livebirths (4·5–4·9) to 2·4 livebirths (2·2–2·5), and the ASFR of mothers aged 10–19 years decreased from 37 livebirths (34–40) to 22 livebirths (19–24) per 1000 women. Despite reductions in the TFR, the global population has been increasing by an average of 83·8 million people per year since 1985. The global population increased by 197·2% (193·3–200·8) since 1950, from 2·6 billion (2·5–2·6) to 7·6 billion (7·4–7·9) people in 2017; much of this increase was in the proportion of the global population in south Asia and sub-Saharan Africa. The global annual rate of population growth increased between 1950 and 1964, when it peaked at 2·0%; this rate then remained nearly constant until 1970 and then decreased to 1·1% in 2017. Population growth rates in the southeast Asia, east Asia, and Oceania GBD super-region decreased from 2·5% in 1963 to 0·7% in 2017, whereas in sub-Saharan Africa, population growth rates were almost at the highest reported levels ever in 2017, when they were at 2·7%. The global average age increased from 26·6 years in 1950 to 32·1 years in 2017, and the proportion of the population that is of working age (age 15–64 years) increased from 59·9% to 65·3%. At the national level, the TFR decreased in all countries and territories between 1950 and 2017; in 2017, TFRs ranged from a low of 1·0 livebirths (95% UI 0·9–1·2) in Cyprus to a high of 7·1 livebirths (6·8–7·4) in Niger. The TFR under age 25 years (TFU25; number of livebirths expected by age 25 years for a hypothetical woman who survived the age group and was exposed to current ASFRs) in 2017 ranged from 0·08 livebirths (0·07–0·09) in South Korea to 2·4 livebirths (2·2–2·6) in Niger, and the TFR over age 30 years (TFO30; number of livebirths expected for a hypothetical woman ageing from 30 to 54 years who survived the age group and was exposed to current ASFRs) ranged from a low of 0·3 livebirths (0·3–0·4) in Puerto Rico to a high of 3·1 livebirths (3·0–3·2) in Niger. TFO30 was higher than TFU25 in 145 countries and territories in 2017. 33 countries had a negative population growth rate from 2010 to 2017, most of which were located in central, eastern, and western Europe, whereas population growth rates of more than 2·0% were seen in 33 of 46 countries in sub-Saharan Africa. In 2017, less than 65% of the national population was of working age in 12 of 34 high-income countries, and less than 50% of the national population was of working age in Mali, Chad, and Niger. Interpretation: Population trends create demographic dividends and headwinds (ie, economic benefits and detriments) that affect national economies and determine national planning needs. Although TFRs are decreasing, the global population continues to grow as mortality declines, with diverse patterns at the national level and across age groups. To our knowledge, this is the first study to provide transparent and replicable estimates of population and fertility, which can be used to inform decision making and to monitor progress. Funding: Bill & Melinda Gates Foundation.
|
|
| 3. |
- Stanaway, Jeffrey D., et al.
(författare)
-
Global, regional, and national comparative risk assessment of 84 behavioural, environmental and occupational, and metabolic risks or clusters of risks for 195 countries and territories, 1990-2017: A systematic analysis for the Global Burden of Disease Study 2017
- 2018
-
Ingår i: The Lancet. - 1474-547X .- 0140-6736. ; 392:10159, s. 1923-1994
-
Tidskriftsartikel (refereegranskat)abstract
- Background The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017 comparative risk assessment (CRA) is a comprehensive approach to risk factor quantification that offers a useful tool for synthesising evidence on risks and risk-outcome associations. With each annual GBD study, we update the GBD CRA to incorporate improved methods, new risks and risk-outcome pairs, and new data on risk exposure levels and risk- outcome associations. Methods We used the CRA framework developed for previous iterations of GBD to estimate levels and trends in exposure, attributable deaths, and attributable disability-adjusted life-years (DALYs), by age group, sex, year, and location for 84 behavioural, environmental and occupational, and metabolic risks or groups of risks from 1990 to 2017. This study included 476 risk-outcome pairs that met the GBD study criteria for convincing or probable evidence of causation. We extracted relative risk and exposure estimates from 46 749 randomised controlled trials, cohort studies, household surveys, census data, satellite data, and other sources. We used statistical models to pool data, adjust for bias, and incorporate covariates. Using the counterfactual scenario of theoretical minimum risk exposure level (TMREL), we estimated the portion of deaths and DALYs that could be attributed to a given risk. We explored the relationship between development and risk exposure by modelling the relationship between the Socio-demographic Index (SDI) and risk-weighted exposure prevalence and estimated expected levels of exposure and risk-attributable burden by SDI. Finally, we explored temporal changes in risk-attributable DALYs by decomposing those changes into six main component drivers of change as follows: (1) population growth; (2) changes in population age structures; (3) changes in exposure to environmental and occupational risks; (4) changes in exposure to behavioural risks; (5) changes in exposure to metabolic risks; and (6) changes due to all other factors, approximated as the risk-deleted death and DALY rates, where the risk-deleted rate is the rate that would be observed had we reduced the exposure levels to the TMREL for all risk factors included in GBD 2017.
|
|
| 4. |
- Jabbar, Abdul, et al.
(författare)
-
Epidemiology and antibiogram of common mastitis-causing bacteria in Beetal goats
- 2020
-
Ingår i: Veterinary World. - : Veterinary World. - 0972-8988 .- 2231-0916. ; 13:12, s. 2596-2607
-
Tidskriftsartikel (refereegranskat)abstract
- Background and Aim: Mastitis has been identified as the most prevalent and economically imperative disease among dairy animals. Thus, understanding its common bacterial pathogens and risk factors is necessary to improve udder health at herd, region, or country level. However, scientific research on caprine mastitis, especially on Beetal breed, has remained to be insufficient in Pakistan. Therefore, this study aimed to evaluate the epidemiology and antibiogram assay of common mastitis-causing bacterial agents, that is, Staphylococcus, Streptococcus, and Escherichia coli, in dairy goats.Materials and Methods: In total, 500 Beetal goats, irrespective of age and those that were not treated with any kind of antimicrobial agents during the past 120 h, were screened using California Mastitis Test in Pattoki, Kasur District, whereas epidemiological factors were recorded. The milk samples of mastitic goats were then collected and processed using standard methods. Each sample was primarily cultured on nutrient agar. Using a specific medium, each bacterial colony was separated using several streak methods. Six antibiotic disks belonging to different antibiotic groups were used for antibiogram profiling of bacterial isolates. Chi-square test was used to assess the association of baseline characteristics and mastitis occurrence. Meanwhile, multivariable logistic regression (p<0.001) was utilized to determine the risk factors associated with positive and negative dichotomous outcome of mastitis.Results: The results revealed that the overall prevalence of goat mastitis was 309 (61.8%), in which 260 (52%) and 49 (9.8%) cases were positive for subclinical mastitis (SCM) and clinical mastitis (CM), respectively. Streptococcus and E. coli were found to be the predominant isolates causing SCM and CM, respectively (p<0.001). It was observed that amoxicillin+clavulanic acid was highly sensitive to isolates of Staphylococcus and Streptococcus and ceftiofur sodium to isolates of Streptococcus and E. coli, while enrofloxacin was found to be sensitive to isolates of Streptococcus and E. coli. Risk factors such as herd structure, deworming, vaccination, presence of ticks, use of teat dip and mineral supplements, feeding type, age, parity, housing, blood in the milk, milk leakage, milk taste, and milk yield were found to have the strongest association with mastitis occurrence, while ease of milking has moderate association.Conclusion: In the area examined, cases of SCM were found to be higher compared with that of CM, and ceftiofur sodium has been identified as the preferred treatment in both clinical and subclinical forms of caprine mastitis in Beetal goats. Risk factors for mastitis that was identified in this study can form the basis for the creation of an udder health control program specific for dairy goats. We hope our findings could raise awareness of the risk factors and treatment approaches for common mastitis-causing bacterial agents.
|
|
| 5. |
- Wang, Haidong, et al.
(författare)
-
Global, regional, and national life expectancy, all-cause mortality, and cause-specific mortality for 249 causes of death, 1980-2015 : a systematic analysis for the Global Burden of Disease Study 2015
- 2016
-
Ingår i: The Lancet. - 0140-6736 .- 1474-547X. ; 388:10053, s. 1459-1544
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Improving survival and extending the longevity of life for all populations requires timely, robust evidence on local mortality levels and trends. The Global Burden of Disease 2015 Study (GBD 2015) provides a comprehensive assessment of all-cause and cause-specific mortality for 249 causes in 195 countries and territories from 1980 to 2015. These results informed an in-depth investigation of observed and expected mortality patterns based on sociodemographic measures.METHODS: We estimated all-cause mortality by age, sex, geography, and year using an improved analytical approach originally developed for GBD 2013 and GBD 2010. Improvements included refinements to the estimation of child and adult mortality and corresponding uncertainty, parameter selection for under-5 mortality synthesis by spatiotemporal Gaussian process regression, and sibling history data processing. We also expanded the database of vital registration, survey, and census data to 14 294 geography-year datapoints. For GBD 2015, eight causes, including Ebola virus disease, were added to the previous GBD cause list for mortality. We used six modelling approaches to assess cause-specific mortality, with the Cause of Death Ensemble Model (CODEm) generating estimates for most causes. We used a series of novel analyses to systematically quantify the drivers of trends in mortality across geographies. First, we assessed observed and expected levels and trends of cause-specific mortality as they relate to the Socio-demographic Index (SDI), a summary indicator derived from measures of income per capita, educational attainment, and fertility. Second, we examined factors affecting total mortality patterns through a series of counterfactual scenarios, testing the magnitude by which population growth, population age structures, and epidemiological changes contributed to shifts in mortality. Finally, we attributed changes in life expectancy to changes in cause of death. We documented each step of the GBD 2015 estimation processes, as well as data sources, in accordance with Guidelines for Accurate and Transparent Health Estimates Reporting (GATHER).FINDINGS: Globally, life expectancy from birth increased from 61·7 years (95% uncertainty interval 61·4-61·9) in 1980 to 71·8 years (71·5-72·2) in 2015. Several countries in sub-Saharan Africa had very large gains in life expectancy from 2005 to 2015, rebounding from an era of exceedingly high loss of life due to HIV/AIDS. At the same time, many geographies saw life expectancy stagnate or decline, particularly for men and in countries with rising mortality from war or interpersonal violence. From 2005 to 2015, male life expectancy in Syria dropped by 11·3 years (3·7-17·4), to 62·6 years (56·5-70·2). Total deaths increased by 4·1% (2·6-5·6) from 2005 to 2015, rising to 55·8 million (54·9 million to 56·6 million) in 2015, but age-standardised death rates fell by 17·0% (15·8-18·1) during this time, underscoring changes in population growth and shifts in global age structures. The result was similar for non-communicable diseases (NCDs), with total deaths from these causes increasing by 14·1% (12·6-16·0) to 39·8 million (39·2 million to 40·5 million) in 2015, whereas age-standardised rates decreased by 13·1% (11·9-14·3). Globally, this mortality pattern emerged for several NCDs, including several types of cancer, ischaemic heart disease, cirrhosis, and Alzheimer's disease and other dementias. By contrast, both total deaths and age-standardised death rates due to communicable, maternal, neonatal, and nutritional conditions significantly declined from 2005 to 2015, gains largely attributable to decreases in mortality rates due to HIV/AIDS (42·1%, 39·1-44·6), malaria (43·1%, 34·7-51·8), neonatal preterm birth complications (29·8%, 24·8-34·9), and maternal disorders (29·1%, 19·3-37·1). Progress was slower for several causes, such as lower respiratory infections and nutritional deficiencies, whereas deaths increased for others, including dengue and drug use disorders. Age-standardised death rates due to injuries significantly declined from 2005 to 2015, yet interpersonal violence and war claimed increasingly more lives in some regions, particularly in the Middle East. In 2015, rotaviral enteritis (rotavirus) was the leading cause of under-5 deaths due to diarrhoea (146 000 deaths, 118 000-183 000) and pneumococcal pneumonia was the leading cause of under-5 deaths due to lower respiratory infections (393 000 deaths, 228 000-532 000), although pathogen-specific mortality varied by region. Globally, the effects of population growth, ageing, and changes in age-standardised death rates substantially differed by cause. Our analyses on the expected associations between cause-specific mortality and SDI show the regular shifts in cause of death composition and population age structure with rising SDI. Country patterns of premature mortality (measured as years of life lost [YLLs]) and how they differ from the level expected on the basis of SDI alone revealed distinct but highly heterogeneous patterns by region and country or territory. Ischaemic heart disease, stroke, and diabetes were among the leading causes of YLLs in most regions, but in many cases, intraregional results sharply diverged for ratios of observed and expected YLLs based on SDI. Communicable, maternal, neonatal, and nutritional diseases caused the most YLLs throughout sub-Saharan Africa, with observed YLLs far exceeding expected YLLs for countries in which malaria or HIV/AIDS remained the leading causes of early death.INTERPRETATION: At the global scale, age-specific mortality has steadily improved over the past 35 years; this pattern of general progress continued in the past decade. Progress has been faster in most countries than expected on the basis of development measured by the SDI. Against this background of progress, some countries have seen falls in life expectancy, and age-standardised death rates for some causes are increasing. Despite progress in reducing age-standardised death rates, population growth and ageing mean that the number of deaths from most non-communicable causes are increasing in most countries, putting increased demands on health systems.
|
|
| 6. |
- Muzaffar, Nimra, et al.
(författare)
-
Designing of VCuS@MXene nanocomposite electrode for energy storage device and electrochemical glucose sensor
- 2024
-
Ingår i: Journal of materials science. Materials in electronics. - : Springer Nature. - 0957-4522 .- 1573-482X. ; 35:9
-
Tidskriftsartikel (refereegranskat)abstract
- MXene, a two-dimensional (2D) material composed of transition metal carbides (TMCs) and nitrides, have fascinated substantial scientific interest. This increased interest results from their exceptional properties, which include extraordinary conductivity, transparency, outstanding absorbing capacity, and significant charge storage capacities. In this work, the MXene-doped vanadium copper sulfide (VCuS) was synthesized through the hydrothermal method. In three electrode measurement system, the VCuS/MXene composite electrode showed exhibited a specific capacity (Qs) of 1620 Cg−1. As application point of view, the hybrid device is designed and measured the electrochemical properties. The hybrid device showed the remarkable Qs of 1528 C.g−1, power density (Pd) of 2347 Wkg−1 and an energy density (Ed) of 34.99 Whkg−1. Further, the VCuS/MXene//AC device is measured up to 6000 cycles to check the stability and durability. The device showed the capacity retention (CR) of 88.5% and a high Coulombic efficiency of 82.6%. Additionally, the VCuS/MXene electrode material is utilized as an electrochemical glucose sensor for the precise detection of H2O2 down to a minimal concentration of H2O2/mm, exhibiting exceptional precision. The use of multifunctional VCuS/MXene nanocomposite electrode material presents novel possibilities for the construction of hybrid energy harvesting systems.
|
|
| 7. |
- Wang, Haidong, et al.
(författare)
-
Estimates of global, regional, and national incidence, prevalence, and mortality of HIV, 1980-2015 : the Global Burden of Disease Study 2015.
- 2016
-
Ingår i: The lancet. HIV. - : Elsevier. - 2352-3018. ; 3:8, s. e361-e387
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Timely assessment of the burden of HIV/AIDS is essential for policy setting and programme evaluation. In this report from the Global Burden of Disease Study 2015 (GBD 2015), we provide national estimates of levels and trends of HIV/AIDS incidence, prevalence, coverage of antiretroviral therapy (ART), and mortality for 195 countries and territories from 1980 to 2015.METHODS: For countries without high-quality vital registration data, we estimated prevalence and incidence with data from antenatal care clinics and population-based seroprevalence surveys, and with assumptions by age and sex on initial CD4 distribution at infection, CD4 progression rates (probability of progression from higher to lower CD4 cell-count category), on and off antiretroviral therapy (ART) mortality, and mortality from all other causes. Our estimation strategy links the GBD 2015 assessment of all-cause mortality and estimation of incidence and prevalence so that for each draw from the uncertainty distribution all assumptions used in each step are internally consistent. We estimated incidence, prevalence, and death with GBD versions of the Estimation and Projection Package (EPP) and Spectrum software originally developed by the Joint United Nations Programme on HIV/AIDS (UNAIDS). We used an open-source version of EPP and recoded Spectrum for speed, and used updated assumptions from systematic reviews of the literature and GBD demographic data. For countries with high-quality vital registration data, we developed the cohort incidence bias adjustment model to estimate HIV incidence and prevalence largely from the number of deaths caused by HIV recorded in cause-of-death statistics. We corrected these statistics for garbage coding and HIV misclassification.FINDINGS: Global HIV incidence reached its peak in 1997, at 3·3 million new infections (95% uncertainty interval [UI] 3·1-3·4 million). Annual incidence has stayed relatively constant at about 2·6 million per year (range 2·5-2·8 million) since 2005, after a period of fast decline between 1997 and 2005. The number of people living with HIV/AIDS has been steadily increasing and reached 38·8 million (95% UI 37·6-40·4 million) in 2015. At the same time, HIV/AIDS mortality has been declining at a steady pace, from a peak of 1·8 million deaths (95% UI 1·7-1·9 million) in 2005, to 1·2 million deaths (1·1-1·3 million) in 2015. We recorded substantial heterogeneity in the levels and trends of HIV/AIDS across countries. Although many countries have experienced decreases in HIV/AIDS mortality and in annual new infections, other countries have had slowdowns or increases in rates of change in annual new infections.INTERPRETATION: Scale-up of ART and prevention of mother-to-child transmission has been one of the great successes of global health in the past two decades. However, in the past decade, progress in reducing new infections has been slow, development assistance for health devoted to HIV has stagnated, and resources for health in low-income countries have grown slowly. Achievement of the new ambitious goals for HIV enshrined in Sustainable Development Goal 3 and the 90-90-90 UNAIDS targets will be challenging, and will need continued efforts from governments and international agencies in the next 15 years to end AIDS by 2030.
|
|
| 8. |
- Bentham, James, et al.
(författare)
-
A century of trends in adult human height
- 2016
-
Ingår i: eLIFE. - 2050-084X. ; 5
-
Tidskriftsartikel (refereegranskat)abstract
- Being taller is associated with enhanced longevity, and higher education and earnings. We reanalysed 1472 population-based studies, with measurement of height on more than 18.6 million participants to estimate mean height for people born between 1896 and 1996 in 200 countries. The largest gain in adult height over the past century has occurred in South Korean women and Iranian men, who became 20.2 cm (95% credible interval 17.522.7) and 16.5 cm (13.319.7) taller, respectively. In contrast, there was little change in adult height in some sub-Saharan African countries and in South Asia over the century of analysis. The tallest people over these 100 years are men born in the Netherlands in the last quarter of 20th century, whose average heights surpassed 182.5 cm, and the shortest were women born in Guatemala in 1896 (140.3 cm; 135.8144.8). The height differential between the tallest and shortest populations was 19-20 cm a century ago, and has remained the same for women and increased for men a century later despite substantial changes in the ranking of countries.
|
|
| 9. |
- Bentham, James, et al.
(författare)
-
A century of trends in adult human height
- 2016
-
Ingår i: eLIFE. - : eLife Sciences Publications Ltd. - 2050-084X. ; 5
-
Tidskriftsartikel (refereegranskat)abstract
- Being taller is associated with enhanced longevity, and higher education and earnings. We reanalysed 1472 population-based studies, with measurement of height on more than 18.6 million participants to estimate mean height for people born between 1896 and 1996 in 200 countries. The largest gain in adult height over the past century has occurred in South Korean women and Iranian men, who became 20.2 cm (95% credible interval 17.5–22.7) and 16.5 cm (13.3– 19.7) taller, respectively. In contrast, there was little change in adult height in some sub-Saharan African countries and in South Asia over the century of analysis. The tallest people over these 100 years are men born in the Netherlands in the last quarter of 20th century, whose average heights surpassed 182.5 cm, and the shortest were women born in Guatemala in 1896 (140.3 cm; 135.8– 144.8). The height differential between the tallest and shortest populations was 19-20 cm a century ago, and has remained the same for women and increased for men a century later despite substantial changes in the ranking of countries.
|
|
| 10. |
|
|
| 11. |
- Hameed, Arslan, et al.
(författare)
-
ZIF-12/Fe-Cu LDH Composite as a High Performance Electrocatalyst for Water Oxidation
- 2021
-
Ingår i: Frontiers in Chemistry. - : Frontiers Media S.A.. - 2296-2646. ; 9
-
Tidskriftsartikel (refereegranskat)abstract
- Layered double hydroxides (LDH) are being used as electrocatalysts for oxygen evolution reactions (OERs). However, low current densities limit their practical applications. Herein, we report a facile and economic synthesis of an iron-copper based LDH integrated with a cobalt-based metal-organic framework (ZIF-12) to form LDH-ZIF-12 composite (1) through a co-precipitation method. The as-synthesized composite 1 requires a low overpotential of 337 mV to achieve a catalytic current density of 10 mA cm−2 with a Tafel slope of 89 mV dec−1. Tafel analysis further demonstrates that 1 exhibits a slope of 89 mV dec−1 which is much lower than the slope of 284 mV dec−1 for LDH and 172 mV dec−1 for ZIF-12. The slope value of 1 is also lower than previously reported electrocatalysts, including Ni-Co LDH (113 mV dec−1) and Zn-Co LDH nanosheets (101 mV dec−1), under similar conditions. Controlled potential electrolysis and stability test experiments show the potential application of 1 as a heterogeneous electrocatalyst for water oxidation.
|
|
| 12. |
- Abbafati, Cristiana, et al.
(författare)
-
- 2020
-
Tidskriftsartikel (refereegranskat)
|
|
| 13. |
- Aibinu, A.M., et al.
(författare)
-
A New Method of Correcting Uneven Illumination Problem in Fundus Images
- 2007
-
Konferensbidrag (refereegranskat)abstract
- Recent advancements in signal and image processing have reduced the time of diagnoses, effort and pressure on the screeners by providing auto diagnostic tools for different diseases. The success rate of these tools greatly depend on the quality of acquired images. Bad image quality can significantly reduce the specificity and the sensitivity which in turn forces screeners back to their tedious job of manual diagnoses. In acquired fundus images, some areas appear to be brighter than the other, that is areas close to the center of the image are always well illuminated, hence appear very bright while areas far from the center are poorly illuminated hence appears to be very dark. Several techniques including the simple thresholding, Naka Rushton (NR) filtering technique and histogram equalization (HE) method have been suggested by various researchers to overcome this problem. However, each of these methods has limitations at their own and hence the need to develop a more robust technique that will provide better performance with greater flexibility. A new method of compensating uneven (irregular) illumination in fundus images termed global-local adaptive histogram equalization using partially-overlapped windows (GLAPOW) is proposed in this paper. The developed algorithm has been tested and the results obtained show superior performance when compared to other known techniques for uneven illumination correction.
|
|
| 14. |
- Aibinu, A.M., et al.
(författare)
-
Automatic Diagnosis of Diabetic Retinopathy from Fundus Images Using Digital Signal and Image Processing Techniques
- 2007
-
Konferensbidrag (refereegranskat)abstract
- Automatic diagnosis and display of diabetic retinopathy from images of retina using the techniques of digital signal and image processing is presented in this paper. The acquired images undergo pre-processing to equalize uneven illumination associated with the acquired fundus images. This stage also removes noise present in the image. Segmentation stage clusters the image into two distinct classes while the abnormalities detection stage was used to distinguish between candidate lesions and other information. Methods of diagnosis of red spots, bleeding and detection of vein-artery crossover points have also been developed in this work using the color information, shape, size, object length to breadth ration as contained in the acquired digital fundus image. Furthermore, two graphical user interfaces (GUIs) have also been developed during this work; the first is for the collection of lesion data information and was used by the ophthalmologist in marking images for database while the second GUI is for automatic diagnosing and displaying of the result in a user friendly manner. The algorithm was tested with a separate set of 25 fundus images. From this, the result obtained for microaneurysms and haemorrhages diagnosis shows the appropriateness of the method.
|
|
| 15. |
- Aibinu, A.M., et al.
(författare)
-
Vascular intersection detection in retina fundus images using a new hybrid approach
- 2010
-
Ingår i: Computers in Biology and Medicine. - : Elsevier. - 0010-4825 .- 1879-0534. ; 40:1, s. 81-89
-
Tidskriftsartikel (refereegranskat)abstract
- The use of vascular intersection aberration as one of the signs when monitoring and diagnosing diabetic retinopathy from retina fundus images (FIs) has been widely reported in the literature. In this paper, a new hybrid approach called the combined cross-point number (CCN) method able to detect the vascular bifurcation and intersection points in FIs is proposed. The CCN method makes use of two vascular intersection detection techniques, namely the modified cross-point number (MCN) method and the simple cross-point number (SCN) method. Our proposed approach was tested on images obtained from two different and publicly available fundus image databases. The results show a very high precision, accuracy, sensitivity and low false rate in detecting both bifurcation and crossover points compared with both the MCN and the SCN methods.
|
|
| 16. |
- Feigin, Valery L., et al.
(författare)
-
Global, regional, and national burden of stroke and its risk factors, 1990-2019 : a systematic analysis for the Global Burden of Disease Study 2019
- 2021
-
Ingår i: Lancet Neurology. - : Elsevier. - 1474-4422 .- 1474-4465. ; 20:10, s. 795-820
-
Tidskriftsartikel (refereegranskat)abstract
- Background Regularly updated data on stroke and its pathological types, including data on their incidence, prevalence, mortality, disability, risk factors, and epidemiological trends, are important for evidence-based stroke care planning and resource allocation. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) aims to provide a standardised and comprehensive measurement of these metrics at global, regional, and national levels. Methods We applied GBD 2019 analytical tools to calculate stroke incidence, prevalence, mortality, disability-adjusted life-years (DALYs), and the population attributable fraction (PAF) of DALYs (with corresponding 95% uncertainty intervals [UIs]) associated with 19 risk factors, for 204 countries and territories from 1990 to 2019. These estimates were provided for ischaemic stroke, intracerebral haemorrhage, subarachnoid haemorrhage, and all strokes combined, and stratified by sex, age group, and World Bank country income level. Findings In 2019, there were 12.2 million (95% UI 11.0-13.6) incident cases of stroke, 101 million (93.2-111) prevalent cases of stroke, 143 million (133-153) DALYs due to stroke, and 6.55 million (6.00-7.02) deaths from stroke. Globally, stroke remained the second-leading cause of death (11.6% [10.8-12.2] of total deaths) and the third-leading cause of death and disability combined (5.7% [5.1-6.2] of total DALYs) in 2019. From 1990 to 2019, the absolute number of incident strokes increased by 70.0% (67.0-73.0), prevalent strokes increased by 85.0% (83.0-88.0), deaths from stroke increased by 43.0% (31.0-55.0), and DALYs due to stroke increased by 32.0% (22.0-42.0). During the same period, age-standardised rates of stroke incidence decreased by 17.0% (15.0-18.0), mortality decreased by 36.0% (31.0-42.0), prevalence decreased by 6.0% (5.0-7.0), and DALYs decreased by 36.0% (31.0-42.0). However, among people younger than 70 years, prevalence rates increased by 22.0% (21.0-24.0) and incidence rates increased by 15.0% (12.0-18.0). In 2019, the age-standardised stroke-related mortality rate was 3.6 (3.5-3.8) times higher in the World Bank low-income group than in the World Bank high-income group, and the age-standardised stroke-related DALY rate was 3.7 (3.5-3.9) times higher in the low-income group than the high-income group. Ischaemic stroke constituted 62.4% of all incident strokes in 2019 (7.63 million [6.57-8.96]), while intracerebral haemorrhage constituted 27.9% (3.41 million [2.97-3.91]) and subarachnoid haemorrhage constituted 9.7% (1.18 million [1.01-1.39]). In 2019, the five leading risk factors for stroke were high systolic blood pressure (contributing to 79.6 million [67.7-90.8] DALYs or 55.5% [48.2-62.0] of total stroke DALYs), high body-mass index (34.9 million [22.3-48.6] DALYs or 24.3% [15.7-33.2]), high fasting plasma glucose (28.9 million [19.8-41.5] DALYs or 20.2% [13.8-29.1]), ambient particulate matter pollution (28.7 million [23.4-33.4] DALYs or 20.1% [16.6-23.0]), and smoking (25.3 million [22.6-28.2] DALYs or 17.6% [16.4-19.0]). Interpretation The annual number of strokes and deaths due to stroke increased substantially from 1990 to 2019, despite substantial reductions in age-standardised rates, particularly among people older than 70 years. The highest age-standardised stroke-related mortality and DALY rates were in the World Bank low-income group. The fastest-growing risk factor for stroke between 1990 and 2019 was high body-mass index. Without urgent implementation of effective primary prevention strategies, the stroke burden will probably continue to grow across the world, particularly in low-income countries.
|
|
| 17. |
- Gencel, Cigdem, et al.
(författare)
-
A Decision Support Framework for Metric Selection in Goal-Based Measurement Programs : GQM-DSFMS
- 2013
-
Ingår i: Journal of Systems and Software. - : Elsevier. - 0164-1212. ; 86:12, s. 3091-3108
-
Tidskriftsartikel (refereegranskat)abstract
- Software organizations face challenges in managing and sustaining their measurement programs over time. The complexity of measurement programs increase with exploding number of goals and metrics to collect. At the same time, organizations usually have limited budget and resources for metrics collection. It has been recognized for quite a while that there is the need for prioritizing goals, which then ought to drive the selection of metrics. On the other hand, the dynamic nature of the organizations requires measurement programs to adapt to the changes in the stakeholders, their goals, information needs and priorities. Therefore, it is crucial for organizations to use structured approaches that provide transparency, traceability and guidance in choosing an optimum set of metrics that would address the highest priority information needs considering limited resources. This paper proposes a decision support framework for metrics selection (DSFMS) which is built upon the widely used Goal Question Metric (GQM) approach. The core of the framework includes an iterative goal-based metrics selection process incorporating decision making mechanisms in metrics selection, a pre-defined Attributes/Metrics Repository, and a Traceability Model among GQM elements. We also discuss alternative prioritization and optimization techniques for organizations to tailor the framework according to their needs. The evaluation of the GQM-DSFMS framework was done through a case study in a CMMI Level 3 software company.
|
|
| 18. |
- Iqbal, Muhammad Imran, et al.
(författare)
-
A Framework for Error Protection of Region of Interest Coded Images and Videos
- 2011
-
Ingår i: Signal processing. Image communication. - : Elsevier. - 0923-5965 .- 1879-2677. ; 26:4-5, s. 236-249
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper, we propose a framework for unequal error protection (UEP) of image and video streaming over a wireless channel. Our framework of allocating the parity symbols associated with error control coding to the image or video codestream takes advantage of the different levels of importance that particular spatial regions of visual multimedia content has to human observers. As such, it provides stronger protection against transmission impairments to those parts of an image or video stream that correspond to the regions of interest (ROIs) while weaker protection is applied to the background (BG). For this purpose, an image or video stream represented by a sequence of packets is split into smaller cells in such a way that certain cells contain the parts of a codestream that represent ROIs and the last cell carries solely BG information. The available parity budget obtained from the given code rate is then distributed among these cells based on their contribution to the overall perceptual quality of a reconstructed image or video. A dynamic programming approach is utilized to facilitate optimal allocation of parity to ROIs and BG for ROI based UEP. The performance of the proposed ROI based UEP scheme in terms of a objective perceptual quality metric is analyzed and compared with both the optimal UEP without ROI processing and equal error protection (EEP) using the structural similarity (SSIM) index. Performance results validate the effectiveness of our framework and the superior performance of the proposed UEP scheme compared to EEP. The performance of the proposed UEP scheme matches well with that of the optimal UEP without ROI processing, especially, for multiple spatial description image and video coding while computational complexity can be kept much lower.
|
|
| 19. |
- Iqbal, Muhammad Imran, et al.
(författare)
-
Detection of Vascular Intersection in Retina Fundus Image Using Modified Cross Point Number and Neural Network Technique
- 2008
-
Konferensbidrag (refereegranskat)abstract
- Vascular intersection can be used as one of the symptoms for monitoring and diagnosis of diabetic retinopathy from fundus images. In this work we apply the knowledge of digital image processing, fuzzy logic and neural network technique to detect bifurcation and vein-artery cross-over points in fundus images. The acquired images undergo preprocessing stage for illumination equalization and noise removal. Segmentation stage clusters the image into two distinct classes by the use of fuzzy c-means technique, neural network technique and modified cross-point number (MCN) methods were employed for the detection of bifurcation and cross-over points. MCN uses a 5x5 window with 16 neighboring pixels for efficient detection of bifurcation and cross over points in fundus images. Result obtained from applying this hybrid method on both real and simulated vascular points shows that this method perform better than the existing simple cross-point number (SCN) method, thus an improvement to the vascular point detection and a good tool in the monitoring and diagnosis of diabetic retinopathy. ©2008 IEEE.
|
|
| 20. |
- Iqbal, Muhammad Imran, et al.
(författare)
-
Error Protection for Wireless Imaging : Providing a Trade-off Between Performance and Complexity
- 2010
-
Konferensbidrag (refereegranskat)abstract
- In this paper, we propose a number of error protection schemes for wireless imaging ranging from simple but less efficient equal error protection to very complex yet optimal error protection. The main objective is to facilitate tradeoffs between performance and complexity in choosing an error protection scheme. Our technique provides the system designer with a number of solutions from which the application can choose those that best suits the available resources such as processing power and data rate. For this purpose, an image codestream is split into smaller cells each having a certain number of packets while the available parity symbols from the deployed error protection are optimally allocated to these cells. Subsequently, the parity symbols allocated to these cells are distributed among the packets that constitute each of these cell. Finally, the error control codes for every packet are determined based on the number of parity symbols allocated to each packet. Larger cells provide less complex but also less efficient error protection while smaller cells result in a better error protection performance but at the cost of increased complexity. Simulation results validate the effectiveness of the considered technique in providing the desired performances-complexity trade-off. To obtain better correlation with human perception, performance is evaluated in terms of objective perceptual quality metrics.
|
|
| 21. |
- Iqbal, Muhammad Imran, et al.
(författare)
-
Error Sensitivity Analysis for Wireless JPEG2000 Using Perceptual Quality Metrics
- 2008
-
Konferensbidrag (refereegranskat)abstract
- Quality assessment of mobile and wireless multimedia services including image and video applications has gained increased attention in recent years as a means of facilitating efficient radio resource management. In particular, approaches that utilize perceptual-based metrics are becoming more dominant, as conventional fidelity metrics such as the peak signal-to-noise ratio (PSNR) may not correlate well with quality as perceived by the human observer. In this paper, we focus on the error sensitivity analysis for images given in the wireless JPEG2000 (JPWL) format using perceptual quality metrics. Specifically, the perceptual quality improvements obtained by progressively decoding an increasing number of image packets are examined. It is shown that the considered perceptual quality metrics exploiting structural image features may accompany or replace the PSNR-based error sensitivity description (ESD) marker segment in the wireless JPEG2000 standard. This addition will increase the effectiveness of the ESD marker segment as it facilitates the communication of reduced-reference information about the image quality from the transmitter to the receiver. In addition, the proposed approach can be used to guide the design of preferential error control coding schemes, link adaptation techniques, and selective retransmission of packets with respect to their contribution to overall quality as perceived by humans.
|
|
| 22. |
- Iqbal, Muhammad Imran, et al.
(författare)
-
Error sensitivity analysis of DMB transport streams
- 2019
-
Ingår i: IEEE Access. - : Institute of Electrical and Electronics Engineers Inc.. - 2169-3536. ; 7, s. 154424-154434
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper, we examine the sensitivity of the digital multimedia broadcasting (DMB) MPEG-2 transport stream (TS) format to transmission errors. To find the sensitivity of different parts of TS packets to transmission errors, each TS packet is divided into four cells, i.e., the first three cells comprising 48 bytes each and the last cell is of 44 bytes length. Bit errors are then introduced into these different parts of the TS packets. The sensitivity of DMB videos to transmission errors and their locations is assessed in terms of the following measures: 1) Number of decoder crashes; 2) Number of decodable videos; 3) Total number of decodable frames; and 4) Objective perceptual video quality of the decoded videos. The structural similarity index and visual information fidelity criterion are used as objective perceptual quality metrics. Simulations are performed on seven different DMB videos using various bit error rates. The results show that the first cell of the TS packets is highly sensitive to bit errors compared to the subsequent three cells, both in terms of spatial and temporal video quality. Further, the sensitivity decreases from Cell 1 to Cell 4 of a DMB TS packet. The error sensitivity analysis reported in this paper may guide the development of more reliable transmission systems for future DMB systems and services. Specifically, the insights gained from this study may support designing better error control schemes that take the sensitivity of different parts of DMB TS packets into consideration.
|
|
| 23. |
- Iqbal, Muhammad Imran
(författare)
-
On Perception-Based Error Protection for Mobile Multimedia
- 2012
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Representation of multimedia requires large amounts of data. Therefore, multimedia source signals are compressed to reduce the data rate that would otherwise be required for its transmission. However, compression renders multimedia data more vulnerable to transmission errors. Therefore, error protection is needed when transmitting multimedia to mobile users over wireless channels. As channel coding adds parity symbols to the data for error protection, which in turn increases transmission data rate, efficient utilization of this added parity budget becomes a key for insuring quality of service for mobile multimedia. Computing the optimal parity allocation among packets of a multimedia stream may not be possible in realtime due to the huge number of ways the parity can be assigned to these packets. Therefore, it is important to design powerful error protection schemes while imposing low computational and memory demands on the system. This is particularly true for systems having limited resources, such as mobile handheld devices. Given that human beings are the final judges on the quality of multimedia services, it will also be beneficial to use perceptual quality metrics that correlate well with human perception when evaluating different error protection schemes. In this work, we have considered the above aspects when designing error protection for mobile multimedia: Providing near optimal performance while keeping complexity low; designing and evaluating of error protection schemes based on perceptual quality metrics. The thesis is divided into five parts. In the first part, region of interest (ROI) identification, coding and advantages of ROI coding are investigated. In addition, a framework is proposed for using ROI coding in wireless imaging. The second part provides a number of unequal error protection (UEP) schemes for wireless imaging ranging from very simple and less efficient equal error protection to very complex yet optimal error protection. The proposed error protection schemes provide an excellent trade-off between performance and omplexity. In the third part, a framework for perception-based error protection of images and video streams is proposed. This framework is based on the fact that the human visual system is more sensitive to quality degradation in the ROI compared to the background. The proposed error protection scheme provides excellent performance. Part four deals with realtime systems and/or systems having limited memory and processing resources. Specifically, an UEP is proposed for wireless imaging systems which provides near optimal performance and puts very low processing/memory demands on the systems. Finally, in the fifth part, optimal UEP is analyzed. Based on the analysis, optimal UEP is modeled using several mathematical models. Each of the considered models is evaluated for its fitness in providing error protection. The simulation results show that most of the investigated models give excellent performance.
|
|
| 24. |
- Iqbal, Muhammad Imran, et al.
(författare)
-
On Region of Interest Coding for Wireless Imaging
- 2007
-
Konferensbidrag (refereegranskat)abstract
- Numerous studies in the fields of human vision and electronic imaging have revealed that the human visual system (HVS) tends to focus on a few preferred areas for given typical images/scenes. Subjective experiments have also shown a strong correlation for these preferred areas among the involved test subjects provided that the same context is viewed. In light of the limited available and expensive resources in technical systems such as mobile multimedia systems, it would therefore be favorable to explore findings about the operation of the HVS in the design of technical communication systems. This paper aims at stimulating such HVS driven approaches in the context of preferential image coding; the region of interest (ROI) coding and its potential application in wireless imaging. In particular, we will elaborate on the general concepts of ROI coding, propose a framework for ROI coding for wireless imaging, review ROI identification mechanisms, and discuss ROI support by non-standardized techniques and ROI support in the JPEG2000 standard. As this paper is of conceptual nature, the work will be consolidated in a classification of contemporary ROI coding techniques including a discussion of their advantages and disadvantages. As a consequence, a number of application areas of ROI coding are identified with the major focus given to the field of wireless imaging.
|
|
| 25. |
- Iqbal, Muhammad Imran, et al.
(författare)
-
Perceptual-based quality assessment of error protection schemes for wireless JPEG2000
- 2009
-
Konferensbidrag (refereegranskat)abstract
- Designing wireless imaging services with acceptable quality imposes great challenges due to the severe impairments induced by wireless channels, high data rate demands and limited transmission bandwidth. In this paper, we examine different error protection schemes for the JPEG2000 codestream using the error control codes offered by the wireless JPEG2000 (JPWL) standard. In particular, two unequal error protection (UEP) schemes are considered. In the first scheme, only the initial and more important packets of the JPWL codestream are protected while the remaining packets are left without protection. In contrast, the second scheme uses a strong code for the initial packets while a weaker code is used for the tail packets. As quality of visual services may not be captured adequately with traditional link layer metrics, code selection and their performance assessment is based on perceptual quality metrics. Specifically, the LP -norm, structural similarity (SSIM) index and visual information fidelity (VIF) criterion are utilized. Numerical results are provided for a range of system conditions under which UEP outperforms conventional equal error protection in terms of perceptual quality metrics.
|
|
| 26. |
- Iqbal, Muhammad Imran
(författare)
-
Preferential Coding for Mobile Multimedia Services
- 2010
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Different parts of source encoded multimedia streams such as those associated with standard image or video formats possess different levels of importance with respect to their contribution to the quality of the reconstructed image or video. This unequal importance among data within a codestream gives rise to preferential treatment of the more significant parts of the codestream compared to the less important parts. Similarly, visual information offered by certain regions of an image or video may attract viewer’s attention more than other parts of the viewing area. As a consequence, preferential treatment of important data and information can play a vital role in mobile multimedia services in order to preserve satisfactory quality of service under the harsh conditions of a band-limited, error-prone wireless channel. In this thesis, we therefore, investigate how preferential coding can be used to protect multimedia services more efficiently against transmission errors. For this purpose, an error sensitivity analysis of the specific application is utilized as a basis to design efficient unequal error protection (UEP) schemes. The performance of the proposed preferential coding schemes is evaluated using objective perceptual quality metrics in order to account for the fact that humans are the ultimate judges of service quality. The thesis is divided into four parts. In the first part, region of interest (ROI) identification, coding and advantages of ROI coding for different applications are investigated. In addition, a framework is proposed for using ROI coding in wireless imaging. The second part analyses the error sensitivity of wireless JPEG2000 (JPWL) in terms of perceptual quality metrics. It is also shown that using reduced- reference perceptual quality metrics as error sensitivity descriptor (ESD) in JPWL increases the effectiveness of ESD. Specifically, this type of metrics correlates well with subjective quality assessment and provides an additional estimate for the obtained quality. In the third part, two UEP schemes for JPWL are proposed and compared with equal error protection (EEP). Their performance is evaluated in terms of perceptual quality metrics such as structural similarity index and the visual information fidelity criterion of the reconstructed image and their benefit over EEP is revealed. Finally, in the fourth part, a framework for optimized preferential coding of ROI based images and videos is proposed. Specifically, a dynamic programming algorithm for optimal parity distribution is provided.
|
|
| 27. |
- Iqbal, Muhammad Imran, et al.
(författare)
-
Quality Assessment of Error Protection Schemes for Wireless JPEG2000
- 2010
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Wireless imaging services suffer large impairments due to the hostile nature of the wireless channel. Given the limited and expensive channel bandwidth and the high data demanding nature of these services, it becomes a challenging task to provide high quality of service in such error prone channels. Clearly, suitable error protection is necessary in order to maintain sufficient quality of these services under various channel conditions. In this report, therefore, we have investigated different channel error protection schemes for a wide range of channel conditions and coding rates. Two unequal error protection (UEP) schemes have been examined for JPEG2000 images exploiting useful features of the JPEG2000 codestream and using the error protection tool set provided by wireless JPEG2000 (JPWL). Taking the importance of the initial codestream packets on the reconstruction of the image at the receiver into account, the first scheme uses all the additional bandwidth resources in protecting the initial packets of the codestream. The rest of the packets, which are of relatively low importance, are transmitted without any parity symbols assigned to them. In the second UEP scheme, the initial parts of the codestream are strongly protected by assigning them an increased amount of parity symbols. In addition, the tail packets of the codestream are also protected but using a weaker error control code compared to the initial packets. The performance of the proposed UEP schemes has been investigated in terms of the peak signal-to-noise ratio as a typical fidelity metric and three perceptual quality metrics, namely, the Lp-norm, the structural similarity index, and the visual information fidelity criterion. Numerical results of the proposed UEP schemes have been compared with conventional equal error protection (EEP) over additive white Gaussian noise (AWGN) channel as well as Rayleigh fading channel in the presence of AWGN. The results reveal the superior performance of the suggested UEP schemes compared to EEP over a range of channel signal-to-noise ratios and code rates.
|
|
| 28. |
- Iqbal, Muhammad Imran, et al.
(författare)
-
Real-Time Unequal Error Protection for Wireless Imaging
- 2011
-
Konferensbidrag (refereegranskat)abstract
- In this paper, we propose a new unequal error protection (UEP) scheme for wireless imaging. Our technique is based on approximating the optimal parity distribution using offline and online processing. For a given parity budget and signal to-noise ratio (SNR), the offline processing is responsible for obtaining the optimal parity distribution and an approximation of it using polynomial curve fitting. Subsequently, in the online processing, the obtained polynomial parameters are used to regenerate the parity distribution curve. Eventually, channel codes are assigned to the packets of the codestream based on the regenerated parity distribution curve. The complexity of the proposed technique is very low which makes it suitable for real-time wireless imaging, especially for mobile devices that have low processing power and operate with very low memory. Despite having very low complexity, the proposed UEP technique gives still close to optimal performance.
|
|
| 29. |
- Iqbal, Muhammad Imran, et al.
(författare)
-
Spatio-Temporal Quality of Experience Trade-offs for Mobile Imaging Applications
- 2010
-
Konferensbidrag (refereegranskat)abstract
- In this paper, we focus on mobile images given in JPEG2000 format and evaluate their spatio-temporal Quality of Experience (QoE). In particular, the trade-of between spatial QoE supported by progressive source encoding and temporal QoE related to network delay as well as initial transmission delay is examined.
|
|
| 30. |
- Iqbal, Muhammad, et al.
(författare)
-
Symbol error rate minimization using deep learning approaches for short-reach optical communication networks
- 2024
-
Ingår i: Frontiers in Physics. - : Frontiers Media S.A.. - 2296-424X. ; 12
-
Tidskriftsartikel (refereegranskat)abstract
- Short-reach optical communication networks have various applications in areas where high-speed connectivity is needed, for example, inter- and intra-data center links, optical access networks, and indoor and in-building communication systems. Machine learning (ML) approaches provide a key solution for numerous challenging situations due to their robust decision-making, problem-solving, and pattern-recognition abilities. In this work, our focus is on utilizing deep learning models to minimize symbol error rates in short-reach optical communication setups. Various channel impairments, such as nonlinearity, chromatic dispersion (CD), and attenuation, are accurately modeled. Initially, we address the challenge of modeling a nonlinear channel. Consequently, we harness a deep learning model called autoencoders (AEs) to facilitate communication over nonlinear channels. Furthermore, we investigate how the inclusion of a nonlinear channel within an autoencoder influences the received constellation as the optical fiber length increases. Another facet of our work involves the deployment of a deep neural network-based receiver utilizing a channel influenced by chromatic dispersion. By gradually extending the optical length, we explore its impact on the received constellation and, consequently, the symbol error rate. Finally, we incorporate the split-step Fourier method (SSFM) to emulate the combined effects of nonlinearities, chromatic dispersion, and attenuation in the optical channel. This is accomplished through a neural network-based receiver. The outcome of this work is an evaluation and reduction of the symbol error rate as the length of the optical fiber is varied.
|
|
| 31. |
- Javaid, Nadeem, et al.
(författare)
-
An Enhanced Energy Balanced Data Transmission Protocol for Underwater Acoustic Sensor Networks
- 2016
-
Ingår i: Sensors. - : MDPI AG. - 1424-8220. ; 16:4
-
Tidskriftsartikel (refereegranskat)abstract
- This paper presents two new energy balanced routing protocols for Underwater Acoustic Sensor Networks (UASNs); Efficient and Balanced Energy consumption Technique (EBET) and Enhanced EBET (EEBET). The first proposed protocol avoids direct transmission over long distance to save sufficient amount of energy consumed in the routing process. The second protocol overcomes the deficiencies in both Balanced Transmission Mechanism (BTM) and EBET techniques. EBET selects relay node on the basis of optimal distance threshold which leads to network lifetime prolongation. The initial energy of each sensor node is divided into energy levels for balanced energy consumption. Selection of high energy level node within transmission range avoids long distance direct data transmission. The EEBET incorporates depth threshold to minimize the number of hops between source node and sink while eradicating backward data transmissions. The EBET technique balances energy consumption within successive ring sectors, while, EEBET balances energy consumption of the entire network. In EEBET, optimum number of energy levels are also calculated to further enhance the network lifetime. Effectiveness of the proposed schemes is validated through simulations where these are compared with two existing routing protocols in terms of network lifetime, transmission loss, and throughput. The simulations are conducted under different network radii and varied number of nodes.
|
|
| 32. |
- Kassebaum, Nicholas J., et al.
(författare)
-
Global, regional, and national disability-adjusted life-years (DALYs) for 315 diseases and injuries and healthy life expectancy (HALE), 1990-2015 : a systematic analysis for the Global Burden of Disease Study 2015
- 2016
-
Ingår i: The Lancet. - 0140-6736 .- 1474-547X. ; 388:10053, s. 1603-1658
-
Tidskriftsartikel (refereegranskat)abstract
- Background Healthy life expectancy (HALE) and disability-adjusted life-years (DALYs) provide summary measures of health across geographies and time that can inform assessments of epidemiological patterns and health system performance, help to prioritise investments in research and development, and monitor progress toward the Sustainable Development Goals (SDGs). We aimed to provide updated HALE and DALYs for geographies worldwide and evaluate how disease burden changes with development. Methods We used results from the Global Burden of Diseases, Injuries, and Risk Factors Study 2015 (GBD 2015) for all-cause mortality, cause-specific mortality, and non-fatal disease burden to derive HALE and DALYs by sex for 195 countries and territories from 1990 to 2015. We calculated DALYs by summing years of life lost (YLLs) and years of life lived with disability (YLDs) for each geography, age group, sex, and year. We estimated HALE using the Sullivan method, which draws from age-specific death rates and YLDs per capita. We then assessed how observed levels of DALYs and HALE differed from expected trends calculated with the Socio-demographic Index (SDI), a composite indicator constructed from measures of income per capita, average years of schooling, and total fertility rate. Findings Total global DALYs remained largely unchanged from 1990 to 2015, with decreases in communicable, neonatal, maternal, and nutritional (Group 1) disease DALYs off set by increased DALYs due to non-communicable diseases (NCDs). Much of this epidemiological transition was caused by changes in population growth and ageing, but it was accelerated by widespread improvements in SDI that also correlated strongly with the increasing importance of NCDs. Both total DALYs and age-standardised DALY rates due to most Group 1 causes significantly decreased by 2015, and although total burden climbed for the majority of NCDs, age-standardised DALY rates due to NCDs declined. Nonetheless, age-standardised DALY rates due to several high-burden NCDs (including osteoarthritis, drug use disorders, depression, diabetes, congenital birth defects, and skin, oral, and sense organ diseases) either increased or remained unchanged, leading to increases in their relative ranking in many geographies. From 2005 to 2015, HALE at birth increased by an average of 2.9 years (95% uncertainty interval 2.9-3.0) for men and 3.5 years (3.4-3.7) for women, while HALE at age 65 years improved by 0.85 years (0.78-0.92) and 1.2 years (1.1-1.3), respectively. Rising SDI was associated with consistently higher HALE and a somewhat smaller proportion of life spent with functional health loss; however, rising SDI was related to increases in total disability. Many countries and territories in central America and eastern sub-Saharan Africa had increasingly lower rates of disease burden than expected given their SDI. At the same time, a subset of geographies recorded a growing gap between observed and expected levels of DALYs, a trend driven mainly by rising burden due to war, interpersonal violence, and various NCDs. Interpretation Health is improving globally, but this means more populations are spending more time with functional health loss, an absolute expansion of morbidity. The proportion of life spent in ill health decreases somewhat with increasing SDI, a relative compression of morbidity, which supports continued efforts to elevate personal income, improve education, and limit fertility. Our analysis of DALYs and HALE and their relationship to SDI represents a robust framework on which to benchmark geography-specific health performance and SDG progress. Country-specific drivers of disease burden, particularly for causes with higher-than-expected DALYs, should inform financial and research investments, prevention efforts, health policies, and health system improvement initiatives for all countries along the development continuum.
|
|
| 33. |
- Khan, Muhammad Abbas, et al.
(författare)
-
mmWave Four-Element MIMO Antenna for Future 5G Systems
- 2022
-
Ingår i: Applied Sciences. - : MDPI AG. - 2076-3417. ; 12:9, s. 4280-
-
Tidskriftsartikel (refereegranskat)abstract
- This paper presents an S-shape four-port Multiple Input Multiple Output (MIMO) wideband mmWave antenna with bandwidth of 25 GHz to 39 GHz. The antenna is designed on 0.254 mm ultra-thin RO5880 with permittivity of 2.3. The dimensions of proposed S-shape antenna are 10 x 12 mm for single element and 24 x 24 mm for four-port MIMO configuration. A decoupling network is introduced to further compress mutual coupling among MIMO elements. The peak gain achieved is 7.1 dBi and MIMO assembly delivers diversity scheme. The proposed MIMO antenna is fabricated, and simulated results are found to be in excellent agreement with simulations. Through the results obtained, the proposed MIMO antenna system can be considered as a potential candidate for future mmWave devices.
|
|
| 34. |
- Khatibi, Siamak, et al.
(författare)
-
Device and method for processing a stream of video data
- 2018
-
Patent (populärvet., debatt m.m.)abstract
- A device for processing a stream of video data which comprises a sequence of frames comprises an interface configured to receive the stream of video data. A processing device is configured to create a three-dimensional environment from a frame of the sequence of frames when a freeze condition is detected. The processing device is configured to generate a series of frames from the three-dimensional environment. The series of frames represents the three-dimensional environment from a plurality of points of view. The processing device is configured to insert the generated series of frames into the sequence of frames to generate a modified sequence of frames to conceal a freeze.
|
|
| 35. |
- Zepernick, Hans-Juergen, et al.
(författare)
-
DMB Video Quality Enhancement Using Header Syntax Repair
- 2022
-
Ingår i: 32nd International Telecommunication Networks and Applications Conference, ITNAC 2022. - : Institute of Electrical and Electronics Engineers (IEEE). - 9781665471039 ; , s. 219-226
-
Konferensbidrag (refereegranskat)abstract
- This paper studies a header syntax repair approach for quality enhancement of digital video broadcasting (DMB) videos. A sensitivity analysis of the impact of transmission errors in different parts of the header of the underlying MPEG-2 transport stream packets on DMB video quality is provided. On this basis, a header syntax repair approach is presented using header masks and bounded minimum distance decoding of the headers of the received DMB packets. Objective and subjective quality assessment show a tremendous improvement in the quality of the header syntax repaired DMB video clips. The concepts of the header syntax repair approach proposed for packets of DMB video streams may also be adapted to the syntax of packet formats of other digital video standards. © 2022 IEEE.
|
|
| 36. |
- Zepernick, Hans-Jürgen, et al.
(författare)
-
Quality of Experience of Digital Multimedia Broadcasting Services : An Experimental Study
- 2016
-
Ingår i: 2016 IEEE Sixth International Conference on Communications and Electronics (ICCE). - : IEEE. - 9781509018017 ; , s. 437-442
-
Konferensbidrag (refereegranskat)abstract
- Digital multimedia broadcasting (DMB), also know as mobile TV, has been developed as a digital radio transmission technology that supports multimedia services such as TV, radio and datacasting. Especially, the terrestrial version of DMB, referred to as T-DMB, has been widely deployed in South Korea to deliver multimedia services to mobile devices ranging from smartphones to laptops, car navigation systems, and telematic devices for automotives. Although T-DMB is claimed to theoretically work without difficulties in vehicles with speeds up to 300 km/h, in practice, occasional skips and other temporal and spatial artifacts have been observed. In this paper, we provide an experimental study of the Quality of Experience (QoE) of T-DMB with focus on TV services. The study is based on a measurement campaign that was conducted in a live T-DMB system in South Korea consisting of TV broadcasters and DMB receivers in vehicles. In particular, a comprehensive subjective test has been conducted on the DMB test material that was obtained in the measurement campaign. A statistical analysis of the user ratings obtained from the subjective tests is reported to quantify the QoE of T-DMB in terms of mean opinion scores (MOSs) and higher order statistics. The obtained results may be used to develop related QoE models for this type of systems and services. In particular, the results may suggest to exploit insights obtained from higher order statistics such as skewness and kurtosis into QoE modeling rather than considering only MOS and variance.
|
|
