| 1. |
- Lozano, Rafael, et al.
(author)
-
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
-
In: The Lancet. - : Elsevier. - 1474-547X .- 0140-6736. ; 392:10159, s. 2091-2138
-
Journal article (peer-reviewed)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. |
- Stanaway, Jeffrey D., et al.
(author)
-
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
-
In: The Lancet. - 1474-547X .- 0140-6736. ; 392:10159, s. 1923-1994
-
Journal article (peer-reviewed)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.
|
|
| 3. |
- Abbafati, Cristiana, et al.
(author)
-
- 2020
-
Journal article (peer-reviewed)
|
|
| 4. |
- Murray, Christopher J. L., et al.
(author)
-
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
-
In: The Lancet. - 1474-547X .- 0140-6736. ; 392:10159, s. 1995-2051
-
Journal article (peer-reviewed)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.
|
|
| 5. |
- Bravo, L, et al.
(author)
-
- 2021
-
swepub:Mat__t
|
|
| 6. |
|
|
| 7. |
- Tabiri, S, et al.
(author)
-
- 2021
-
swepub:Mat__t
|
|
| 8. |
|
|
| 9. |
- Danaei, Goodarz, et al.
(author)
-
Iran in transition
- 2019
-
In: The Lancet. - 0140-6736 .- 1474-547X. ; 393:10184, s. 1984-2005
-
Research review (peer-reviewed)abstract
- Being the second-largest country in the Middle East, Iran has a long history of civilisation during which several dynasties have been overthrown and established and health-related structures have been reorganised. Iran has had the replacement of traditional practices with modern medical treatments, emergence of multiple pioneer scientists and physicians with great contributions to the advancement of science, environmental and ecological changes in addition to large-scale natural disasters, epidemics of multiple communicable diseases, and the shift towards non-communicable diseases in recent decades. Given the lessons learnt from political instabilities in the past centuries and the approaches undertaken to overcome health challenges at the time, Iran has emerged as it is today. Iran is now a country with a population exceeding 80 million, mainly inhabiting urban regions, and has an increasing burden of non-communicable diseases, including cardiovascular diseases, hypertension, diabetes, malignancies, mental disorders, substance abuse, and road injuries.
|
|
| 10. |
- Akbar, Nabeela, et al.
(author)
-
Tunning tin-based perovskite as an electrolyte for semiconductor protonic fuel cells
- 2022
-
In: International journal of hydrogen energy. - : Elsevier BV. - 0360-3199 .- 1879-3487. ; 47:8, s. 5531-5540
-
Journal article (peer-reviewed)abstract
- The use of ceramic semiconductors to serve as an efficient proton conductor is an evolving approach in the novel emerging field of semiconductor protonic fuel cells (SPFCs). One of the most critical challenges in SPFCs is to design a sufficient proton-conductivity of 0.1 S cm(-1) below <600 degrees C. Here we report to tune the perovskite BaSnO3 (BSO), a semi-conductor single-phase material, to be applied as a proton-conducting electrolyte for SPFC. It was found that the oxygen vacancies play a vital role to promote proton transport while the electronic short-circuiting issue of BSO semiconductor has been justified by the Schottky junction mechanism at the anode/electrolyte interface. We have demonstrated a SPFC device to deliver a maximum power density of 843 mW cm(-2) with an ionic conductivity of 0.23 S cm(-1) for BSO at 550 degrees C. The oxygen vacancy formation by increasing the annealing temperature helps to understand the proton transport mechanism in BSO and such novel low-temperature SPFC (LT-SPFC).
|
|
| 11. |
- Haghighi, Ali Torabi, et al.
(author)
-
When rain does not run, a fingerprint of uncoordinated water resources development
- 2024
-
In: Journal of Hydrology. - 0022-1694. ; 629
-
Journal article (peer-reviewed)abstract
- The management of water resources in a basin can be challenging due to the sharing of water resources among multiple stakeholders and conflicting interests. This often results in imbalanced water resource development across the basin. While small and medium-sized projects are efficiently implemented in the headwater and upstream areas, the commissioning of large reservoirs faces delays due to the substantial investment required and regulatory processes involved. Also, the lack of coordination and synchronization in water resource development between upstream and downstream regions can lead to water scarcity and inefficient utilization of resources in the lower part of the basin. In this study, we assess the occurrence of water scarcity by comparing the frequency of hydrological and meteorological droughts before and after the detected abrupt change in river flow. To facilitate this assessment, we introduced two new indices: the positive to negative phases of hydrological and meteorological droughts. These indices highlight the increasing occurrence of hydrological droughts, which may not necessarily be linked to meteorological droughts during the identified periods. Furthermore, we propose a Monotone drought analysis method to examine the correlation between meteorological and hydrological droughts and address the impact of anthropogenic activities. We applied this analysis in the Sefid-Rud basin, the largest sub-basin in the southern Caspian Sea situated in Iran, which hosts several dams and reservoirs while more dams are in the construction and planning phase. The assessment took place in 24 gauges across the basin from 1978 to 2017 to detect and evaluate the alterations in flow regimes. Our analysis revealed that the unbalanced development of upstream water resources, driven by uncoordinated water infrastructure projects implemented by various decision-makers, has resulted in a decline of available water at critical points within the basin, which will be aggravated with the commissioning of new dams.
|
|
| 12. |
- Hasani, Bilal, et al.
(author)
-
Collaborative routing and data delivery architecture for commercial wireless sensor networks
- 2013
-
In: EURASIP Journal on Wireless Communications and Networking. - : Springer Science and Business Media LLC. - 1687-1472 .- 1687-1499. ; :1, s. 54-
-
Journal article (peer-reviewed)abstract
- Lately, wireless sensor network applications have emerged for provision of commercial services to end users. This results in commercial deployment of sensor networks which is as an important research area due to a number of design and quality of service challenges. An important technical challenge for sensor service provision to end users is managing dynamic network conditions such as unreliability of sensor nodes and network links which results in frequent service outages. This research is aimed at addressing this challenge. It presents a novel architecture which utilizes the availability of multiple sensor networks under different administrative domains, deployed in an area such that maximum network connectivity and high service availability are ensured. The architecture incorporates modifications and enhancements at the medium access control and the routing layers of sensor nodes for the collaborative operation of sensor networks. The design is based on IEEE 802.15.4 standard and ad hoc on demand distance vector routing protocol. The proposed architecture is mathematically analyzed with regards to overheads associated with the design such as routing and communication, and techniques to minimize these overheads are recommended. Through simulations using OMNET++, we show that the proposed architecture effectively provides connectivity for disconnected nodes achieving an overall increase in throughput for all the cooperating networks.
|
|
| 13. |
- Nejad Ghafar, Ali, 1971-, et al.
(author)
-
Uncertainties in Grout Penetrability Measurements; Evaluation and Comparison of Filter pump, Penetrability meter and Short slot
- 2017
-
In: Geotechnical and Geological Engineering. - : Springer. - 0960-3182 .- 1573-1529.
-
Journal article (peer-reviewed)abstract
- To measure grout penetrability in fractured hard rock, various measuring instruments have been developed over the years. Penetrability meter and Filter pump have been designed to use in both the lab and the field. Short slot has been applicable mainly in the lab due to its complexity. The fact, that these instruments have been built based on different assumptions, limitations, and test conditions, makes their results occasionally in contradict. Deficiency in design of the instruments as well as the methods of evaluating grout penetrability is additionally a basis for uncertainty in results. This study is an experimental effort to determine and thoroughly perceive the nature of the most governing uncertainties in grout penetrability measurements. The test apparatus, procedure, and method used to evaluate the grout penetrability in both Penetrability meter and Filter pump were thus modified. The aim was to control the corresponding uncertainties and make their limitations and test conditions as similar as possible with the ones in Short slot. The results suggested that to obtain a more realistic evaluation of the grout penetrability, measurement should be accomplished at both the high and the low pressures with sufficient grout volume using Short slot. Moreover, application of both Filter pump and Penetrability meter is no longer recommended due to the revealed uncertainties.
|
|
| 14. |
- Sajadi, Leily, et al.
(author)
-
HIV prevalence and related risk behaviours among female sex workers in Iran: results of the national biobehavioural survey, 2010
- 2013
-
In: Sexually Transmitted Infections. - : BMJ. - 1368-4973 .- 1472-3263. ; 89, s. 37-40
-
Journal article (peer-reviewed)abstract
- Objectives To determine the prevalence of HIV and related behavioural risks among Iranian female sex workers (FSW) via the first national biobehavioural surveillance survey. Methods In 2010, 1005 FSW were approached and 872 recruited using facility-based sampling from 21 sites in 14 cities in Iran. We collected dried blood samples and conducted face-to-face interviews using a standardised questionnaire. Data were weighted based on the response rate and adjusted for the clustering effect of the sampling site. Adjustment was performed by weighting based on the sampling fraction of each site using a prior estimate of its total size of the FSW population. Results The prevalence of HIV infection (95% CI) was 4.5% (2.4 to 8.3) overall, 4.8% (2.2 to 9.8) among those who had reported a history of drug use and 11.2% (5.4 to 21.5) among those who had a history of injection drug use. The frequencies of condom use in the last sexual act with paying clients and non-paying partners were 57.1% and 36.3%, respectively. Any drug use was reported by 73.8% of participants, and among this subgroup, 20.5% had a history of injection drug use. Conclusions The prevalence of HIV was considerable among FSW particularly those who had a history of drug injection. A combination of prevention efforts addressing unsafe sex and injection are needed to prevent further transmission of HIV infection.
|
|
| 15. |
- Sharifi, Hamid, et al.
(author)
-
Estimation of HIV incidence and its trend in three key populations in Iran
- 2018
-
In: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 13:11
-
Journal article (peer-reviewed)abstract
- In Iran, People Who Inject Drugs (PWID), Female Sex Workers (FSW), and prisoners are the main key populations at risk of HIV infection. This study aimed to evaluate the trend of HIV incidence among PWID, FSW and prisoners as an impact measure of HIV harm reduction and prevention efforts in Iran. Data were obtained from the two rounds of national bio-behavioral surveillance surveys among FSW (2010 (n = 872), 2015 (n = 1339)), PWID (2010 (n = 2417), 2014 (n = 2307)), and prisoners (2009 (n = 4536), 2013 (n = 5390)) through facility-based (FSW and PWID surveys) and cluster sampling (prisoner surveys). Time-at-risk was calculated assuming the age at first sex or drug injection as the beginning of the at-risk period and the age at the time of the interview or date when they received a positive HIV test result as the end of this period, adjusted for interval censoring. HIV incidence among PWID in 2014 was 5.39 (95% CI 4.71, 6.16) per 1,000 person-years (PY), significantly lower than in 2009 (17.07, 95% CI 15.34, 19.34). Similarly, HIV incidence was 1.12 (95% CI 0.77, 1.64) per 1,000 PY among FSW in 2015, a significant drop from 2010 (2.38, 95% CI 1.66, 3.40). Also, HIV incidence decreased among prisoners from 1.34 (95% CI: 1.08, 1.67) in 2009 to 0.49 (95% CI: 0.39, 0.61) per 1,000 PY in 2013. Our findings suggest that after an increase in the 2000s, the HIV incidence may have been decreased and stabilized among key populations in Iran.
|
|
| 16. |
|
|
| 17. |
- Shokoohi, Mostafa, et al.
(author)
-
Low HIV testing rate and its correlates among men who inject drugs in Iran
- 2016
-
In: International Journal of Drug Policy. - : Elsevier BV. - 0955-3959. ; 32, s. 64-69
-
Journal article (peer-reviewed)abstract
- Background: Iran has a concentrated HIV epidemic among people who inject drugs (PWID). Low HIV testing uptake could contribute to the significant number HIV-infected PWID, who go undiagnosed. This study aims to assess HIV testing uptake and its correlates among PWID in Iran. Methods: Data were collected through a national cross-sectional bio-behavioral study in 2010. Adult male HIV-negative PWID were included in the current analysis. All estimates were adjusted for the clustering effect of the sampling sites. Multivariable logistic regression was used to examine the correlates of recent HIV testing and adjusted odds ratios (AOR) were reported. Results: Out of the 2146 eligible PWID for this study, 49.8% reported having ever tested for HIV. However, only 24.9% had tested in the previous year and received their test results. Around 65.2% of PWID knew an HIV testing site. In the multivariable analysis, knowing an HIV testing site (AOR. = 13.9; P-value.
|
|
| 18. |
- Ali, Akbar, et al.
(author)
-
Silver-chitosan nanobiocomposite as urea biosensor
- 2014
-
In: Optoelectronics and Advanced Materials Rapid Communications. - : NATL INST OPTOELECTRONICS. - 1842-6573 .- 2065-3824. ; 8:11-12, s. 1238-1242
-
Journal article (peer-reviewed)abstract
- Silver nanoparticles (Ag NPs) were synthesized by aqueous chemical growth technique. The above mentioned synthesized materials were characterized by applying scanning electron microscope (SEM) and X-ray diffraction for confirmation of morphological analysis, compositional purity, and crystalline property and emission characteristics as well. In order to fabricate the urea biosensor (potentiometric), a solution of deionized water and chitosan was prepared having Ag NPs. The said solution was dropped on the glass fiber filter having diameter of 2 cm. A wire of copper having thickness of approximately 500 pm was used for the voltage signal to pull out from the said working nanoparticles (NPs). To improve the strength, sensitivity and the quality of the potentiometric urea biosensor, a specific functional surface of Ag NPs was attained by electrostatic restrained of an enzyme (urease) onto the chitosan-Ag (a nanobiocomposite). The potentiometric reaction was measured via electrochemical detection technique. The potentiometric urea biosensor illustrates significant sensibility at room temperature with approximate to 42 mV as per span. Furthermore, the said biosensor showed an appropriate stable response within 7 sec.
|
|
| 19. |
- Ali Ahmad, Syed Ossama, et al.
(author)
-
Application of two-dimensional materials in perovskite solar cells: recent progress, challenges, and prospective solutions
- 2021
-
In: Journal of Materials Chemistry C. - : ROYAL SOC CHEMISTRY. - 2050-7526 .- 2050-7534. ; 9:40, s. 14065-14092
-
Research review (peer-reviewed)abstract
- Perovskite solar cells (per-SCs) with high performance and cost-effective solution processing have been the center of interest for researchers in the past decade. Power conversion efficiencies (PCEs) have been gradually improved up to 25.2% with relatively improved stability, which is an unparalleled progress in all generations of solar cell (SC) technology. However, there are still some prevailing challenges regarding the stability and upscaling of these promising devices. Recently, 2D layered materials (LMs) have been extensively explored to overcome the prevailing challenges of poor stability (under moisture, light soaking and high temperature), halide segregation, hysteresis, involvement of toxic materials (i.e., lead), and upscaling of devices. A critical review addressing the recent developments in the use of 2D materials, especially transition metal dichalcogenides (TMDCs), is hence necessary. The development of novel synthesis and deposition techniques including liquid-metal synthesis and ultrasonic assisted spray pyrolysis has offered more efficient fabrication of 2D-LMs with controlled thickness and morphology. Effective functionalization approaches to increase the dispersability of 2D-LMs in non-polar solvents has boosted their potential application in solar cell technology as well. Moreover, compositing 2D TMDCs with suitable organic/inorganic compounds has enabled superior charge kinetics in all functional parts of per-SCs. In addition, newly developed materials such as graphyne and graphdyine along with 2D metal organic frameworks (MOFs) and covalent organic frameworks (COFs) have been employed in per-SCs to achieve PCEs up to 20%. This review summarizes the recent progress and challenges in the application of 2D-LMs in per-SCs and outlines the future pathways to further extend the PCE of per-SCs beyond 25%. This review particularly focuses on 2D-LMs as electrode materials and additives, the underlying charge (electron-hole) transport phenomenon in the functional layers, and their chemical and structural stability.
|
|
| 20. |
|
|
| 21. |
- Ashkarran, Ali Akbar, et al.
(author)
-
Conformation- and phosphorylation-dependent electron tunnelling across self-assembled monolayers of tau peptides
- 2022
-
In: Journal of Colloid and Interface Science. - : Elsevier BV. - 0021-9797. ; 606, s. 2038-2050
-
Journal article (peer-reviewed)abstract
- We report on charge transport across self-assembled monolayers (SAMs) of short tau peptides by probing the electron tunneling rates and quantum mechanical simulation. We measured the electron tunneling rates across SAMs of carboxyl-terminated linker molecules (C6H12O2S) and short cis-tau (CT) and trans-tau (TT) peptides, supported on template-stripped gold (AuTS) bottom electrode, with Eutectic Gallium-Indium (EGaIn)(EGaIn) top electrode. Measurements of the current density across thousands of AuTS/linker/tau//Ga2O3/EGaIn single-molecule junctions show that the tunneling current across CT peptide is one order of magnitude lower than that of TT peptide. Quantum mechanical simulation demonstrated a wider energy bandgap of the CT peptide, as compared to the TT peptide, which causes a reduction in its electron tunneling current. Our findings also revealed the critical role of phosphorylation in altering the charge transport characteristics of short peptides; more specifically, we found that the presence of phosphate groups can reduce the energy band gap in tau peptides and alter their electrical properties. Our results suggest that conformational and phosphorylation of short peptides (e.g., tau) can significantly change their charge transport characteristics and energy levels.
|
|
| 22. |
- Daelman, Bo, et al.
(author)
-
Frailty and cognitive function in middle-aged and older adults with congenital heart disease
- 2024
-
In: Journal of the American College of Cardiology. - : Elsevier. - 0735-1097 .- 1558-3597. ; 83:12, s. 1149-1159
-
Journal article (peer-reviewed)abstract
- Background: Life expectancy of patients with congenital heart disease (CHD) has increased rapidly, resulting in a growing and aging population. Recent studies have shown that older people with CHD have higher morbidity, health care use, and mortality. To maintain longevity and quality of life, understanding their evolving medical and psychosocial challenges is essential.Objectives: The authors describe the frailty and cognitive profile of middle-aged and older adults with CHD to identify predictor variables and to explore the relationship with hospital admissions and outpatient visits.Methods: Using a cross-sectional, multicentric design, we included 814 patients aged ≥40 years from 11 countries. Frailty phenotype was determined using the Fried method. Cognitive function was assessed by the Montreal Cognitive Assessment.Results: In this sample, 52.3% of patients were assessed as robust, 41.9% as prefrail, and 5.8% as frail; 38.8% had cognitive dysfunction. Multinomial regression showed that frailty was associated with older age, female sex, higher physiologic class, and comorbidities. Counterintuitively, patients with mild heart defects were more likely than those with complex lesions to be prefrail. Patients from middle-income countries displayed more prefrailty than those from higher-income countries. Logistic regression demonstrated that cognitive dysfunction was related to older age, comorbidities, and lower country-level income.Conclusions: Approximately one-half of included patients were (pre-)frail, and more than one-third experienced cognitive impairment. Frailty and cognitive dysfunction were identified in patients with mild CHD, indicating that these concerns extend beyond severe CHD. Assessing frailty and cognition routinely could offer valuable insights into this aging population.
|
|
| 23. |
- Ebadat, Afrooz, et al.
(author)
-
New fuzzy wavelet network for modeling and control:The modeling approach
- 2011
-
In: Communications in Nonlinear Science and Numerical Simulation. - : Elsevier BV. - 1007-5704. ; 16:8, s. 3385-3396
-
Journal article (peer-reviewed)abstract
- n this paper, a fuzzy wavelet network is proposed to approximate arbitrary nonlinear functions based on the theory of multiresolution analysis (MRA) of wavelet transform and fuzzy concepts. The presented network combines TSK fuzzy models with wavelet transform and ROLS learning algorithm while still preserve the property of linearity in parameters. In order to reduce the number of fuzzy rules, fuzzy clustering is invoked. In the clustering algorithm, those wavelets that are closer to each other in the sense of the Euclidean norm are placed in a group and are used in the consequent part of a fuzzy rule. Antecedent parts of the rules are Gaussian membership functions. Determination of the deviation parameter is performed with the help of gold partition method. Here, mean of each function is derived by averaging center of all wavelets that are related to that particular rule. The overall developed fuzzy wavelet network is called fuzzy wave-net and simulation results show superior performance over previous networks.The present work is complemented by a second part which focuses on the control aspects and to be published in this journal([17]). This paper proposes an observer based self-structuring robust adaptive fuzzy wave-net (FWN) controller for a class of nonlinear uncertain multi-input multi-output systems.
|
|
| 24. |
- Fardos, Akbar, et al.
(author)
-
Algorithm to generate efficient circular designs robust to neighbor effects
- 2024
-
In: Kuwait Journal of Science. - 2307-4108. ; 51:1
-
Journal article (peer-reviewed)abstract
- Minimal circular balanced and strongly balanced neighbor designs (MCBNDs & MCSBNDs) are popular to control neighbor effects and to estimate neighbor and direct effects independently. In this article, an R-coded algorithm is presented to obtain efficient MCBNDs and MCSBNDs for odd v (number of treatments), and its four generalized classes for v even. Developed algorithm has made the construction of the efficient circular designs robust to neighbor effects so easy in blocks of equal and unequal sizes.
|
|
| 25. |
- Fiddaman, Steven R., et al.
(author)
-
Ancient chicken remains reveal the origins of virulence in Marek's disease virus
- 2023
-
In: Science (New York, N.Y.). - 1095-9203. ; 382:6676, s. 1276-1281
-
Journal article (peer-reviewed)abstract
- The pronounced growth in livestock populations since the 1950s has altered the epidemiological and evolutionary trajectory of their associated pathogens. For example, Marek's disease virus (MDV), which causes lymphoid tumors in chickens, has experienced a marked increase in virulence over the past century. Today, MDV infections kill >90% of unvaccinated birds, and controlling it costs more than US$1 billion annually. By sequencing MDV genomes derived from archeological chickens, we demonstrate that it has been circulating for at least 1000 years. We functionally tested the Meq oncogene, one of 49 viral genes positively selected in modern strains, demonstrating that ancient MDV was likely incapable of driving tumor formation. Our results demonstrate the power of ancient DNA approaches to trace the molecular basis of virulence in economically relevant pathogens.
|
|
| 26. |
- Ghaffari, Mostafa, et al.
(author)
-
Effect of psychosocial factors on low back pain in industrial workers
- 2008
-
In: Occupational Medicine. - : Oxford University Press (OUP). - 0962-7480 .- 1471-8405. ; 58:5, s. 341-347
-
Journal article (peer-reviewed)abstract
- Aim To test the hypothesis that workplace psychosocial factors such as demand, control, support, job satisfaction and job appreciation can predict the future onset of disabling low back pain (LBP). Methods The present study involved a prospective cohort of 4500 Iranian industrial workers. Data were gathered by means of a self-reported questionnaire about LBP, as well as working life exposure, lifestyle factors, social exposures, co-morbidity, life events and psychosomatic complaints in 2004. All new episodes of disabling LBP resulting in medically certified sick leave during the 1-year follow-up registered by occupational health clinic inside the factory. Results The participation rate was good (85%). A total of 744 subjects reported current LBP (point prevalence cases). A total of 52 (< , 2%) new episodes of disabling LBP were observed during the 1-year follow-up (incident cases). Male employees reported higher demands, lower control and lower support than female employees. Employees with high demands, low control, job strain, low job satisfaction and low job appreciation showed increased odds ratios, and these results were statistically significant. Conclusions Few prospective studies in this field have been published, but all of them are related to industrialized countries. This prospective study suggests the aetiological role of job strain for LBP. The findings of this study indicate a substantial potential for disease prevention and health promotion at the workplace.
|
|
| 27. |
|
|
| 28. |
- Ghorashi, Sayed Ali Akbar, et al.
(author)
-
Topological and Stacked Flat Bands in Bilayer Graphene with a Superlattice Potential
- 2023
-
In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 130:19
-
Journal article (peer-reviewed)abstract
- We show that bilayer graphene in the presence of a 2D superlattice potential provides a highly tunable setup that can realize a variety of flat band phenomena. We focus on two regimes: (i) topological flat bands with nonzero Chern numbers, C, including bands with higher Chern numbers |C|>1 and (ii) an unprecedented phase consisting of a stack of nearly perfect flat bands with C=0. For realistic values of the potential and superlattice periodicity, this stack can span nearly 100 meV, encompassing nearly all of the low-energy spectrum. We further show that in the topological regime, the topological flat band has a favorable band geometry for realizing a fractional Chern insulator (FCI) and use exact diagonalization to show that the FCI is in fact the ground state at 1/3 filling. Our results provide a realistic guide for future experiments to realize a new platform for flat band phenomena.
|
|
| 29. |
- Hussain, Fida, et al.
(author)
-
Comparative electrochemical investigation of zinc based nano-composite anode materials for solid oxide fuel cell
- 2019
-
In: Ceramics International. - : Elsevier. - 0272-8842 .- 1873-3956. ; 45:1, s. 1077-1083
-
Journal article (peer-reviewed)abstract
- The structural and electrochemical properties of zinc based nano-composites anode materials with a composition of X0.25Ti0.5Zn0.70 (where X = Cu, Mn, Ag) have been investigated in this present study. The proposed Xo.zsTiousZno.70 oxide materials have been synthesized through sol-gel method. The doping effect of Cu, Mn, and Ag on TiZn oxides were analyzed in terms of electronic conduction and power density in hydrogen atmosphere at comparatively low temperature in the range of 650 degrees C. The crystal structure and surface morphology were examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis techniques. The XRD patterns of composites depict that the average crystalline sizes lie in the range of 20-100 nm. Four -probe DC conductivity technique was used to measure the conductivity of the materials and maximum electrical conductivity of Ag0.25Ti0.05Zn0.70 oxide was found to be 7.81 S/cm at 650 degrees C. The band gap and absorption spectra were determined by ultra-violet visible (UV-Vis) and Fourier Transform Infrared spectroscopy (FTIR) techniques respectively. The maximum power density was achieved to be 354 mW/cm(2) at 650 degrees C by Ag0.25Ti0.05Zn0.70 oxide anode with SDC (electrolyte) and BSCF (conventional cathode) materials.
|
|
| 30. |
- Imanzadeh, Farid, et al.
(author)
-
Assessing the prevalence and treatment of malnutrition in hospitalized children in Mofid Children's Hospital during 2015-2016
- 2018
-
In: Archives of Iranian Medicine. - 1029-2977 .- 1735-3947. ; 21:7, s. 302-309
-
Journal article (peer-reviewed)abstract
- Background: Malnutrition in hospitalized patients causes problems in treatment and increases hospitalization duration. The aim of this research was to determine the prevalence of malnutrition in hospitalized children.Methods: Children aged 1 month to 18 years (n = 1186) who were admitted to medical and surgery wards of Mofid children’s hospital from November 2015 to February 2016, entered the study. We measured different anthropometric variables in patients with malnutrition. Also, nutritional counseling was performed and three months follow-up was done.Results: Patient data were registered in questionnaires particularly for children 2 years old and less. 597 children under 2 years of age and 607 children over two years entered the study. The data analysis was done by SPSS version 22.0 (Chicago, IL, USA). The t test inferential method was used in comparing variables. P values less than 0.05 were considered statistically significant. Based on the body mass index (BMI) Z score, and in accordance with the World Health Organization (WHO) cut-off, among children over 2 years, 9% were diagnosed as overweight or obese, 54% were within the normal range and 37% were underweight at time of admission. In the underweight group, 43% were mildly, 21.2% were moderately and 35.8% were severely underweight. Based on the weight for length Z score in patients less than 2 years of age at time of admission, 6% were overweight, 60% were in normal range and 34% were underweight. Among children with malnutrition, 21% had mild, 3.0% had moderate and 10% had severe malnutrition. No significant meaningful relation was found between prevalence of malnutrition and severity of illness. In the moderate to severe undernutrition group, nutritionist counseling was done. Comparison of BMI and weight, before and after admission (the baseline and the follow up visits), was done by means of repeated measurements. Comparison of the patient’s weight at time of admission with weight at 1, 2 and 3 months after the first nutritional consultation showed statistically meaningful difference (P value < 0.05).Conclusion: Growth indices need to be evaluated in every hospitalized child. Nutritional consultation is useful in children with malnutrition. The main purpose of early diagnosis of malnutrition is to prevent its progression, and also to design a useful, applicable and cost-effective nutritional intervention for malnutrition treatment.
|
|
| 31. |
- Jamali, Elham, et al.
(author)
-
The significance of surface neutrophilic MPO expression level in NETosis and NETosis-associated coagulopathies in covid-19 infected patients
- 2022
-
In: Blood Cells, Molecules & Diseases. - : ACADEMIC PRESS INC ELSEVIER SCIENCE. - 1079-9796 .- 1096-0961. ; 96
-
Journal article (peer-reviewed)abstract
- Introduction: Inflammatory response-induced coagulopathy is a common complication associated with severe form of covid-19 infection. Evidences suggest that neutrophil extracellular traps (NETs) play a significant role in triggering the immunothrombosis in this condition. We aimed to evaluate the diagnostic value of surface neutrophilic myeloperoxidase (MPO) as NETosis biomarker for predicting the risk of covid-19-associated coagulopathies.Methods: Covid-19 infection was assessed by real-time-PCR and plasma d-dimer levels were measured by ELFA. Based on the covid-19 infection and d-dimer level outcomes, patients were categorized into four groups. Any alteration in the serum level of IL-6, H3Cit and neutrophilic surface MPO were analyzed by CLIA, ELISA, and flow cytometry, respectively.Results: H3Cit variations and different d-dimer values confirmed the association between NETosis and coagu-lopathies. Findings showed that the expression of neutrophilic MPO reduced in cases with NETosis, which was correlated with increased levels of H3Cit. ANC/MPO ratio was signified as a valuable marker to discriminate the covid-19 and non covid-19-associated coagulopathies and could be considered as a prognostic factor due to its noteworthy correlation with serum IL-6 concentration.Conclusion: Declined levels of surface neutrophilic MPO in NETosis correlate with covid-19-associated coagu-lopathies and increased IL-6 levels, as a potential biomarker of covid-19 disease severity.
|
|
| 32. |
- Javadnia, Eslam, et al.
(author)
-
A MODIS-based modeling scheme for the estimation of downward surface shortwave radiation under cloud-free conditions
- 2017
-
In: Arabian Journal of Geosciences. - : Springer. - 1866-7511 .- 1866-7538. ; 10
-
Journal article (peer-reviewed)abstract
- Atmospheric aerosol optical depth (AOD) plays an important role in radiation modeling and partly determines the accuracy of estimated downward surface shortwave radiation (DSSR). In this study, Iqbal’s model C was used to estimate DSSR under cloud-free conditions over the Koohin and Chitgar sites in Tehran, Iran; the estimated DSSR was based on (1) our proposed hybrid modeling scheme where the AOD is retrieved using the Simplified Aerosol Retrieval Algorithm (SARA), ground-based measurements at the AERONET site in Zanjan and (2) the AOD from the Terra MODerate-resolution Imaging Spectroradiometer (MODIS) sensor. Several other Terra MODIS land and atmospheric products were also used as input data, including geolocation properties, water vapor, total ozone, surface reflectance, and top-of-atmosphere (TOA) radiance. SARA-based DSSR and MODIS-based DSSR were evaluated with ground-based DSSR measurements at the Koohin and Chitgar sites in 2011 and 2013, respectively; the averaged statistics for SARA-based DSSR [R2 ≈ 0.95, RMSE ≈ 22 W/m2 (2.5% mean value), and bias ≈ 3 W/m2] were stronger than those for MODIS-based DSSR [R2 ≈ 0.79, RMSE ≈ 51 W/m2 (5.8% mean value), and bias ≈ 34 W/m2]. These results show that the proposed hybrid scheme can be used at regional to global scales under the assumption of future access to spatially distributed AERONET sites. Additionally, the robustness of this modeling scheme was exemplified by estimating the aerosol radiative forcing (ARF) during a dust storm in Southwest Asia. The results were comparable to those of previous studies and showed the strength of our modeling scheme.
|
|
| 33. |
- Javadnia, Eslam, et al.
(author)
-
Estimation of High-Resolution Surface Shortwave Radiative Fluxes Using SARA AOD over the Southern Great Plains
- 2017
-
In: Remote Sensing. - : MDPI. - 2072-4292. ; 9:11
-
Journal article (peer-reviewed)abstract
- Atmospheric aerosol optical depth (AOD) plays a determinant role in estimations of surface shortwave (SW) radiative fluxes. Therefore, this study aims to develop a hybrid scheme to produce surface SW fluxes, based on AOD at 1-km spatial resolution retrieved from the Simplified Aerosol Retrieval Algorithm (SARA) and several Terra MODIS land and atmospheric products (i.e., geolocation properties, water vapor amount, total ozone column, surface reflectance, and top-of-atmosphere (TOA) radiance). Estimations based on SARA were made over the Southern Great Plains (SGP) under cloud-free conditions in 2014 and compared with estimations based on the latest Terra MODIS AOD product at 3-km resolution. Validation against ground-based measurements showed that SARA-based fluxes obtain lower RMSE and bias values compared with MODIS-based estimations. MODIS-based downward and net fluxes are satisfactory, while the direct and diffuse components are less reliable. The results demonstrate that the SARA-based scheme produces better surface SW radiative fluxes than the MODIS-based estimates provided in this and other similar studies and that these fluxes are comparable to existing CERES data products which have been tested over the SGP.
|
|
| 34. |
- Kanellakis, Christoforos, et al.
(author)
-
Towards Autonomous Aerial Scouting Using Multi-Rotors in Subterranean Tunnel Navigation
- 2021
-
In: IEEE Access. - : IEEE. - 2169-3536. ; 9, s. 66477-66485
-
Journal article (peer-reviewed)abstract
- This work establishes a robocentric framework around a non-linear Model Predictive Control (NMPC) for autonomous navigation of quadrotors in tunnel-like environments. The proposed framework enables obstacle free navigation capabilities for resource constraint platforms in areas with critical challenges including darkness, textureless surfaces as well as areas with self-similar geometries, without any prior knowledge. The core contribution of the proposed framework stems from the merging of perception dynamics in a model-based optimization approach, aligning the vehicles heading to the tunnels’ open space expressed in the x axis coordinate in the image frame of the most distant area. Moreover, the aerial vehicle is considered as a free-flying object that plans its actions using egocentric onboard sensors. The proposed method can be deployed in both fully illuminated indoor corridors or featureless dark tunnels, leveraging visual processing from either RGB-D or monocular sensors for generating direction commands to keep flying in the proper direction. Multiple experimental field trials demonstrate the effectiveness of the proposed method in challenging environments.
|
|
| 35. |
- Kanellakis, Christoforos, et al.
(author)
-
Vision-driven NMPC for Autonomous Aerial Navigation in Subterranean Environments
-
Other publication (other academic/artistic)abstract
- This work establishes a novel robocentric Non-linear Model Predictive Control (NMPC) framework for fast fully autonomous navigation of quadrotors in featureless dark tunnel environments. Additionally, this work leverages the processing of a single camera to generate direction commands along the tunnel axis, while regulating the platform's altitude. The extracted visual dynamics are coupled in the sequel with the NMPC problem, structured around the Proximal Averaged Newton-type method for Optimal Control (PANOC), which is a fast numerical optimization method that is not sensitive to ill conditioning and is suitable for embedded NMPC implementations. Multiple fully realistic simulation results demonstrate the effectiveness of the proposed method in challenging environments.
|
|
| 36. |
- Kanellakis, Christoforos, et al.
(author)
-
Vision-driven NMPC for Autonomous Aerial Navigation in Subterranean Environments
- 2020
-
In: 21th IFAC World Congress. - : Elsevier. ; , s. 9288-9294
-
Conference paper (peer-reviewed)abstract
- This work establishes a novel robocentric Non-linear Model Predictive Control (NMPC) framework for fast fully autonomous navigation of quadrotors in featureless dark tunnel environments. Additionally, this work leverages the processing of a single camera to generate direction commands along the tunnel axis, while regulating the platform’s altitude. The extracted visual dynamics are coupled in the sequel with the NMPC problem, structured around the Proximal Averaged Newton-type method for Optimal Control (PANOC), which is a fast numerical optimization method that is not sensitive to ill conditioning and is suitable for embedded NMPC implementations. Multiple fully realistic simulation results demonstrate the effectiveness of the proposed method in challenging environments.
|
|
| 37. |
- Khajehkazemi, Razieh, et al.
(author)
-
HIV prevalence and risk behaviours among people who inject drugs in Iran: the 2010 National Surveillance Survey
- 2013
-
In: Sexually Transmitted Infections. - : BMJ. - 1368-4973 .- 1472-3263. ; 89, s. 29-32
-
Journal article (peer-reviewed)abstract
- Objectives To assess the prevalence of HIV and related risk behaviours among people who inject drugs (PWID) in Iran. Methods We conducted a national cross-sectional bio-behavioural surveillance survey between March and July 2010, interviewing male PWID from a geographically dispersed sample through a facility-based sampling method. Results We recruited 2480, and tested 2290 PWID. The overall prevalence of HIV was 15.2% (95% CI 9.7% to 23.1%). Among those who had injected drugs over the last month, 36.9% had used a non-sterile needle, and 12.6% had practiced shared injection. Over the past 12 months preceding the interview, 30.4% had sold sex for money, drugs, goods or a favour. In the multivariate analysis, the prevalence of HIV had a positive association with age, while having above high school education, and permanent job were protective. Conclusions Unsafe injection, and sexual risk behaviours are still frequent and the prevalence of HIV among PWID remains high. Intensified efforts are needed to prevent the further spread of HIV among Iranian PWID and their sexual partners.
|
|
| 38. |
- Khan, Rizwan, et al.
(author)
-
Dental image enhancement network for early diagnosis of oral dental disease
- 2023
-
In: Scientific Reports. - : Springer Nature. - 2045-2322. ; 13:1
-
Journal article (peer-reviewed)abstract
- Intelligent robotics and expert system applications in dentistry suffer from identification and detection problems due to the non-uniform brightness and low contrast in the captured images. Moreover, during the diagnostic process, exposure of sensitive facial parts to ionizing radiations (e.g., X-Rays) has several disadvantages and provides a limited angle for the view of vision. Capturing high-quality medical images with advanced digital devices is challenging, and processing these images distorts the contrast and visual quality. It curtails the performance of potential intelligent and expert systems and disincentives the early diagnosis of oral and dental diseases. The traditional enhancement methods are designed for specific conditions, and network-based methods rely on large-scale datasets with limited adaptability towards varying conditions. This paper proposed a novel and adaptive dental image enhancement strategy based on a small dataset and proposed a paired branch Denticle-Edification network (Ded-Net). The input dental images are decomposed into reflection and illumination in a multilayer Denticle network (De-Net). The subsequent enhancement operations are performed to remove the hidden degradation of reflection and illumination. The adaptive illumination consistency is maintained through the Edification network (Ed-Net). The network is regularized following the decomposition congruity of the input data and provides user-specific freedom of adaptability towards desired contrast levels. The experimental results demonstrate that the proposed method improves visibility and contrast and preserves the edges and boundaries of the low-contrast input images. It proves that the proposed method is suitable for intelligent and expert system applications for future dental imaging.
|
|
| 39. |
- Khokhar, Javeria, et al.
(author)
-
Prevalence and determinants of anemia among resident female university students from Southern Punjab, Pakistan
- 2022
-
In: Women and Health. - : Informa UK Limited. - 0363-0242 .- 1541-0331. ; 62:6, s. 488-501
-
Journal article (peer-reviewed)abstract
- Health and nutritional status of the women of reproductive age (WRA) is expected to be influenced with women literacy status alongside other sociodemographic indicators. However, data are scant to validate if literate young women have lower incidence of anemia prevalence. Nexus to the problem stated, a cross-sectional study was conducted on 1,541 female resident university students (FRUS) aged 17–35 years from a public sector university located in Southern Punjab, Pakistan. Hemoglobin (Hb) led screening for anemia was performed followed by nutritional assessment and structured questionnaire-based sociodemographic and dietary assessment. The data generated were analyzed using independent t-test, Chi-square, and response surface regression models. Response rate for the prevalence of anemia in FRUS was 38 percent with mean Hb levels 10.5 g/dL. With a significant effect (p =.001) of participants’ weight on anemia prevalence, 22.45 percent of the sample population was recorded as underweight. Sociodemographic and dietary parameters analyzed suggested low daily food expenditure (x 2 = 20.59; p =.000) and reduced intake of meat (x 2 = 12.14; p =.01), beans & pulses (x 2 = 18.56; p =.001) to significantly influence rate of anemia prevalence in FRUS. The study concludes high prevalence rate of anemia among FRUS to strongly relate with students’ low monthly stipend, little daily food expenditure, and substandard dietary quality.
|
|
| 40. |
- Kottayam Viswanathan, Vignesh, et al.
(author)
-
Towards a Reduced Dependency Framework for Autonomous Unified Inspect-Explore Missions
-
Other publication (other academic/artistic)abstract
- The task of establishing and maintaining situational awareness in an unknown environment is a critical step to fulfil in a mission related to the field of rescue robotics. Predominantly, the problem of visual inspection of urban structures is dealt with view-planning being addressed by map-based approaches. In this article, we propose a novel approach towards effective use of Micro Aerial Vehicles (MAVs) for obtaining a 3-D shape of an unknown structure of objects utilizing a map-independent planning framework. The problem is undertaken via a bifurcated approach to address the task of executing a closer inspection of detected structures with a wider exploration strategy to identify and locate nearby structures, while being equipped with limited sensing capability. The proposed framework is evaluated experimentally in a controlled indoor environment in presence of a mock-up environment validating the efficacy of the proposed inspect-explore policy.
|
|
| 41. |
- Koval, Anton, et al.
(author)
-
Dataset collection from a SubT environment
- 2022
-
In: Robotics and Autonomous Systems. - : Elsevier. - 0921-8890 .- 1872-793X. ; 155
-
Journal article (peer-reviewed)abstract
- This article presents a dataset collected from the subterranean (SubT) environment with a current state-of-the-art sensors required for autonomous navigation. The dataset includes sensor measurements collected with RGB, RGB-D, event-based and thermal cameras, 2D and 3D lidars, inertial measurement unit (IMU), and ultra wideband (UWB) positioning systems which are mounted on the mobile robot. The overall sensor setup will be referred further in the article as a data collection platform. The dataset contains synchronized raw data measurements from all the sensors in the robot operating system (ROS) message format and video feeds collected with action and 360 cameras. A detailed description of the sensors embedded into the data collection platform and a data collection process are introduced. The collected dataset is aimed for evaluating navigation, localization and mapping algorithms in SubT environments. This article is accompanied with the public release of all collected datasets from the SubT environment. Link: Dataset (C) 2022 The Author(s). Published by Elsevier B.V.
|
|
| 42. |
- Lindqvist, Björn, et al.
(author)
-
COMPRA: A COMPact Reactive Autonomy Framework for Subterranean MAV Based Search-And-Rescue Operations
- 2022
-
In: Journal of Intelligent and Robotic Systems. - : Springer. - 0921-0296 .- 1573-0409. ; 105:3
-
Journal article (peer-reviewed)abstract
- This work establishes COMPRA, a compact and reactive autonomy framework for fast deployment of Micro Aerial Vehicles (MAVs) in subterranean Search-and- Rescue (SAR) missions. A COMPRA-enabled MAV is able to autonomously explore previously unknown areas while specific mission criteria are considered e.g. an object of interest is identified and localized, the remaining useful battery life, the overall desired exploration mission duration. The proposed architecture follows a low-complexity algorithmic design to facilitate fully on-board computations, including nonlinear control, state-estimation, navigation, exploration behavior and object localization capabilities. The framework is mainly structured around a reactive local avoidance planner, based on enhanced Potential Field concepts and using instantaneous 3D pointclouds, as well as a computationally efficient heading regulation technique, based on depth images from an instantaneous camera stream. Those techniques decouple the collision-free path generation from the dependency of a global map and are capable of handling imprecise localization occasions. Field experimental verification of the overall architecture is performed in relevant unknown Global Positioning System (GPS)-denied environments.
|
|
| 43. |
- Lindqvist, Björn, et al.
(author)
-
Exploration-RRT: A multi-objective Path Planning and Exploration Framework for Unknown and Unstructured Environments
- 2021
-
In: 2021 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS). - : IEEE. ; , s. 3429-3435
-
Conference paper (peer-reviewed)abstract
- This article establishes the Exploration-RRT algorithm: A novel general-purpose combined exploration and path planning algorithm, based on a multi-goal Rapidly-Exploring Random Trees (RRT) framework. Exploration-RRT (ERRT) has been specifically designed for utilization in 3D exploration missions, with partially or completely unknown and unstructured environments. The novel proposed ERRT is based on a multi-objective optimization framework and it is able to take under consideration the potential information gain, the distance travelled, and the actuation costs, along trajectories to pseudo-random goals, generated from considering the on-board sensor model and the non-linear model of the utilized platform. In this article, the algorithmic pipeline of the ERRT will be established and the overall applicability and efficiency of the proposed scheme will be presented on an application with an Unmanned Aerial Vehicle (UAV) model, equipped with a 3D lidar, in a simulated operating environment, with the goal of exploring a completely unknown area as efficiently and quickly as possible.
|
|
| 44. |
- Lindqvist, Björn, et al.
(author)
-
Multimodality robotic systems: Integrated combined legged-aerial mobility for subterranean search-and-rescue
- 2022
-
In: Robotics and Autonomous Systems. - : Elsevier. - 0921-8890 .- 1872-793X. ; 154
-
Journal article (peer-reviewed)abstract
- This work presents a field-hardened autonomous multimodal legged-aerial robotic system for subterranean exploration, extending a legged robot to be the carrier of an aerial platform capable of a rapid deployment in search-and-rescue scenarios. The driving force for developing such robotic configurations are the requirements for large-scale and long-term missions, where the payload capacity and long battery life of the legged robot is combined and integrated with the agile motion of the aerial agent. The multimodal robot is structured around the quadruped Boston Dynamics Spot, enhanced with a custom configured autonomy sensor payload as well as a UAV carrier platform, while the aerial agent is a custom built quadcopter. This work presents the novel design and hardware implementation as well as the onboard sensor suites. Moreover it establishes the overall autonomy architecture in a unified supervision approach while respecting each locomotion modality, including guidance, navigation, perception, state estimation, and control capabilities with a focus on rapid deployment and efficient exploration. The robotic system complete architecture is evaluated in real subterranean tunnel areas, in multiple fully autonomous search-and-rescue missions with the goal of identifying and locating objects of interest within the subterranean environment.
|
|
| 45. |
- Lindqvist, Björn, et al.
(author)
-
Nonlinear MPC for Collision Avoidance and Control of UAVs With Dynamic Obstacles
- 2020
-
In: IEEE Robotics and Automation Letters. - : IEEE. - 2377-3766. ; 5:4, s. 6001-6008
-
Journal article (peer-reviewed)abstract
- This article proposes a Novel Nonlinear Model Predictive Control (NMPC) for navigation and obstacle avoidance of an Unmanned Aerial Vehicle (UAV). The proposed NMPC formulation allows for a fully parametric obstacle trajectory, while in this article we apply a classification scheme to differentiate between different kinds of trajectories to predict futureobstacle positions. The trajectory calculation is done from an initial condition, and fed to the NMPC as an additional input.The solver used is the nonlinear, non-convex solver Proximal Averaged Newton for Optimal Control (PANOC) and its as-sociated software OpEn (Optimization Engine), in which weapply a penalty method to properly consider the obstacles and other constraints during navigation. The proposed NMPC scheme allows for real-time solutions using a sampling time of 50 ms and a two second prediction of both the obstacle trajectory and the NMPC problem, which implies that the scheme can be considered as a local path-planner. This paper will present the NMPC cost function and constraint formulation, as well as the methodology of dealing with the dynamic obstacles. We include multiple laboratory experiments to demonstrate the efficacy ofthe proposed control architecture, and to show that the proposed method delivers fast and computationally stable solutions to the dynamic obstacle avoidance scenarios.
|
|
| 46. |
- Mansouri, Sina Sharif, et al.
(author)
-
A Unified NMPC Scheme for MAVs Navigation With 3D Collision Avoidance Under Position Uncertainty
- 2020
-
In: IEEE Robotics and Automation Letters. - : IEEE. - 2377-3766. ; 5:4, s. 5740-5747
-
Journal article (peer-reviewed)abstract
- This letter proposes a novel Nonlinear Model Predictive Control (NMPC) framework for Micro Aerial Vehicle (MAV) autonomous navigation in indoor enclosed environments. The introduced framework allows us to consider the nonlinear dynamics of MAVs, nonlinear geometric constraints, while guarantees real-time performance. Our first contribution is to reveal underlying planes within a 3D point cloud, obtained from a 3D lidar scanner, by designing an efficient subspace clustering method. The second contribution is to incorporate the extracted information into the nonlinear constraints of NMPC for avoiding collisions. Our third contribution focuses on making the controller robust by considering the uncertainty of localization in NMPC using Shannon's entropy to define the weights involved in the optimization process. This strategy enables us to track position or velocity references or none in the event of losing track of position or velocity estimations. As a result, the collision avoidance constraints are defined in the local coordinates of the MAV and it remains active and guarantees collision avoidance, despite localization uncertainties, e.g., position estimation drifts. The efficacy of the suggested framework has been evaluated using various simulations in the Gazebo environment.
|
|
| 47. |
- Mansouri, Sina Sharif, et al.
(author)
-
Unsupervised Learning for Subterranean Junction Recognition Based on 2D Point Cloud
- 2020
-
In: 2020 28th Mediterranean Conference on Control and Automation (MED). - : IEEE. ; , s. 802-807
-
Conference paper (peer-reviewed)abstract
- This article proposes a novel unsupervised learning framework for detecting the number of tunnel junctions in subterranean environments based on acquired 2D point clouds. The implementation of the framework provides valuable information for high level mission planners to navigate an aerial platform in unknown areas or robot homing missions. The framework utilizes spectral clustering, which is capable of uncovering hidden structures from connected data points lying on non-linear manifolds. The spectral clustering algorithm computes a spectral embedding of the original 2D point cloud by utilizing the eigen decomposition of a matrix that is derived from the pairwise similarities of these points. We validate the developed framework using multiple data-sets, collected from multiple realistic simulations, as well as from real flights in underground environments, demonstrating the performance and merits of the proposed methodology.
|
|
| 48. |
- Palieri, Matteo, et al.
(author)
-
LOCUS : A Multi-Sensor Lidar-Centric Solution for High-Precision Odometry and 3D Mapping in Real-Time
- 2021
-
In: IEEE Robotics and Automation Letters. - : IEEE. - 2377-3766. ; 6:2, s. 421-428
-
Journal article (peer-reviewed)abstract
- A reliable odometry source is a prerequisite to enable complex autonomy behaviour in next-generation robots operating in extreme environments. In this work, we present a high-precision lidar odometry system to achieve robust and real-time operation under challenging perceptual conditions. LOCUS (Lidar Odometry for Consistent operation in Uncertain Settings), provides an accurate multi-stage scan matching unit equipped with an health-aware sensor integration module for seamless fusion of additional sensing modalities. We evaluate the performance of the proposed system against state-of-the-art techniques in perceptually challenging environments, and demonstrate top-class localization accuracy along with substantial improvements in robustness to sensor failures. We then demonstrate real-time performance of LOCUS on various types of robotic mobility platforms involved in the autonomous exploration of the Satsop power plant in Elma, WA where the proposed system was a key element of the CoSTAR team's solution that won first place in the Urban Circuit of the DARPA Subterranean Challenge.
|
|
| 49. |
- Patel, Akash, et al.
(author)
-
REF: A Rapid Exploration Framework for Deploying Autonomous MAVs in Unknown Environments
- 2023
-
In: Journal of Intelligent and Robotic Systems. - : Springer. - 0921-0296 .- 1573-0409. ; 108
-
Journal article (peer-reviewed)abstract
- Exploration and mapping of unknown environments is a fundamental task in applications for autonomous robots. In this article, we present a complete framework for deploying Micro Aerial Vehicles (MAVs) in autonomous exploration missions in unknown subterranean areas. The main motive of exploration algorithms is to depict the next best frontier for the MAV such that new ground can be covered in a fast, safe yet efficient manner. The proposed framework uses a novel frontier selection method that also contributes to the safe navigation of autonomous MAVs in obstructed areas such as subterranean caves, mines, and urban areas. The framework presented in this work bifurcates the exploration problem in local and global exploration. The proposed exploration framework is also adaptable according to computational resources available onboard the MAV which means the trade-off between the speed of exploration and the quality of the map can be made. Such capability allows the proposed framework to be deployed in subterranean exploration and mapping as well as in fast search and rescue scenarios. The performance of the proposed framework is evaluated in detailed simulation studies with comparisons made against a high-level exploration-planning framework developed for the DARPA Sub-T challenge as it will be presented in this article.
|
|
| 50. |
- Patel, Akash, et al.
(author)
-
Towards energy efficient autonomous exploration of Mars lava tube with a Martian coaxial quadrotor
- 2023
-
In: Advances in Space Research. - : Elsevier. - 0273-1177 .- 1879-1948. ; 71:9, s. 3837-3854
-
Journal article (peer-reviewed)abstract
- Mapping and exploration of a Martian terrain with an aerial vehicle has become an emerging research direction, since the successful flight demonstration of the Mars helicopter Ingenuity. Although the autonomy and navigation capability of the state of the art Mars helicopter has proven to be efficient in an open environment, the next area of interest for exploration on Mars are caves or ancient lava tube like environments, especially towards the never-ending search of life on other planets. This article presents an autonomous exploration mission based on a modified frontier approach along with a risk aware planning and integrated collision avoidance scheme with a special focus on energy aspects of a custom designed Mars Coaxial Quadrotor (MCQ) in a Martian simulated lava tube. One of the biggest novelties of the article stems from addressing the exploration capability, while rapidly exploring in local areas and intelligently global re-positioning of the MCQ when reaching dead ends in order to efficiently use the battery based consumed energy, while increasing the volume of the exploration. The proposed novel algorithm for the Martian exploration is able to select the next way point of interest, such that the MCQ keeps its heading towards the local exploration direction where it will find maximum information about the surroundings. The proposed three layer cost based global re-position point selection assists in rapidly redirecting the MCQ to previously partially seen areas that could lead to more unexplored part of the lava tube. The Martian fully simulated mission presented in this article takes into consideration the fidelity of physics of Mars condition in terms of thin atmosphere, low surface pressure and low gravity of the planet, while proves the efficiency of the proposed scheme in exploring an area that is particularly challenging due to the subterranean-like environment. The proposed exploration-planning framework is also validated in simulation by comparing it against the graph based exploration planner. Intensive simulations with true Mars conditions are carried out in order to validate and benchmark our approach in a utmost realistic Mars lava tube exploration scenario using a Mars Coaxial Quadrotor.
|
|
