| 1. |
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
- Thomas, HS, et al.
(författare)
-
- 2019
-
swepub:Mat__t
|
|
| 5. |
|
|
| 6. |
- Drake, TM, et al.
(författare)
-
Surgical site infection after gastrointestinal surgery in children: an international, multicentre, prospective cohort study
- 2020
-
Ingår i: BMJ global health. - : BMJ. - 2059-7908. ; 5:12
-
Tidskriftsartikel (refereegranskat)abstract
- Surgical site infection (SSI) is one of the most common healthcare-associated infections (HAIs). However, there is a lack of data available about SSI in children worldwide, especially from low-income and middle-income countries. This study aimed to estimate the incidence of SSI in children and associations between SSI and morbidity across human development settings.MethodsA multicentre, international, prospective, validated cohort study of children aged under 16 years undergoing clean-contaminated, contaminated or dirty gastrointestinal surgery. Any hospital in the world providing paediatric surgery was eligible to contribute data between January and July 2016. The primary outcome was the incidence of SSI by 30 days. Relationships between explanatory variables and SSI were examined using multilevel logistic regression. Countries were stratified into high development, middle development and low development groups using the United Nations Human Development Index (HDI).ResultsOf 1159 children across 181 hospitals in 51 countries, 523 (45·1%) children were from high HDI, 397 (34·2%) from middle HDI and 239 (20·6%) from low HDI countries. The 30-day SSI rate was 6.3% (33/523) in high HDI, 12·8% (51/397) in middle HDI and 24·7% (59/239) in low HDI countries. SSI was associated with higher incidence of 30-day mortality, intervention, organ-space infection and other HAIs, with the highest rates seen in low HDI countries. Median length of stay in patients who had an SSI was longer (7.0 days), compared with 3.0 days in patients who did not have an SSI. Use of laparoscopy was associated with significantly lower SSI rates, even after accounting for HDI.ConclusionThe odds of SSI in children is nearly four times greater in low HDI compared with high HDI countries. Policies to reduce SSI should be prioritised as part of the wider global agenda.
|
|
| 7. |
|
|
| 8. |
-
- 2019
-
Tidskriftsartikel (refereegranskat)
|
|
| 9. |
- 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.
|
|
| 10. |
- Klionsky, Daniel J., et al.
(författare)
-
Guidelines for the use and interpretation of assays for monitoring autophagy
- 2012
-
Ingår i: Autophagy. - : Informa UK Limited. - 1554-8635 .- 1554-8627. ; 8:4, s. 445-544
-
Forskningsöversikt (refereegranskat)abstract
- In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field.
|
|
| 11. |
- 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.
|
|
| 12. |
|
|
| 13. |
- Abbafati, Cristiana, et al.
(författare)
-
- 2020
-
Tidskriftsartikel (refereegranskat)
|
|
| 14. |
- Feigin, Valery L, et al.
(författare)
-
Global, Regional, and Country-Specific Lifetime Risks of Stroke, 1990 and 2016.
- 2018
-
Ingår i: The New England journal of medicine. - 1533-4406 .- 0028-4793. ; 379:25, s. 2429-2437
-
Tidskriftsartikel (refereegranskat)abstract
- The lifetime risk of stroke has been calculated in a limited number of selected populations. We sought to estimate the lifetime risk of stroke at the regional, country, and global level using data from a comprehensive study of the prevalence of major diseases.We used the Global Burden of Disease (GBD) Study 2016 estimates of stroke incidence and the competing risks of death from any cause other than stroke to calculate the cumulative lifetime risks of first stroke, ischemic stroke, or hemorrhagic stroke among adults 25 years of age or older. Estimates of the lifetime risks in the years 1990 and 2016 were compared. Countries were categorized into quintiles of the sociodemographic index (SDI) used in the GBD Study, and the risks were compared across quintiles. Comparisons were made with the use of point estimates and uncertainty intervals representing the 2.5th and 97.5th percentiles around the estimate.The estimated global lifetime risk of stroke from the age of 25 years onward was 24.9% (95% uncertainty interval, 23.5 to 26.2); the risk among men was 24.7% (95% uncertainty interval, 23.3 to 26.0), and the risk among women was 25.1% (95% uncertainty interval, 23.7 to 26.5). The risk of ischemic stroke was 18.3%, and the risk of hemorrhagic stroke was 8.2%. In high-SDI, high-middle-SDI, and low-SDI countries, the estimated lifetime risk of stroke was 23.5%, 31.1% (highest risk), and 13.2% (lowest risk), respectively; the 95% uncertainty intervals did not overlap between these categories. The highest estimated lifetime risks of stroke according to GBD region were in East Asia (38.8%), Central Europe (31.7%), and Eastern Europe (31.6%), and the lowest risk was in eastern sub-Saharan Africa (11.8%). The mean global lifetime risk of stroke increased from 22.8% in 1990 to 24.9% in 2016, a relative increase of 8.9% (95% uncertainty interval, 6.2 to 11.5); the competing risk of death from any cause other than stroke was considered in this calculation.In 2016, the global lifetime risk of stroke from the age of 25 years onward was approximately 25% among both men and women. There was geographic variation in the lifetime risk of stroke, with the highest risks in East Asia, Central Europe, and Eastern Europe. (Funded by the Bill and Melinda Gates Foundation.).
|
|
| 15. |
|
|
| 16. |
- Muscarella, Robert, et al.
(författare)
-
The global abundance of tree palms
- 2020
-
Ingår i: Global Ecology and Biogeography. - : Wiley. - 1466-822X .- 1466-8238. ; 29:9, s. 1495-1514
-
Tidskriftsartikel (refereegranskat)abstract
- AimPalms are an iconic, diverse and often abundant component of tropical ecosystems that provide many ecosystem services. Being monocots, tree palms are evolutionarily, morphologically and physiologically distinct from other trees, and these differences have important consequences for ecosystem services (e.g., carbon sequestration and storage) and in terms of responses to climate change. We quantified global patterns of tree palm relative abundance to help improve understanding of tropical forests and reduce uncertainty about these ecosystems under climate change.LocationTropical and subtropical moist forests.Time periodCurrent.Major taxa studiedPalms (Arecaceae).MethodsWe assembled a pantropical dataset of 2,548 forest plots (covering 1,191 ha) and quantified tree palm (i.e., ≥10 cm diameter at breast height) abundance relative to co‐occurring non‐palm trees. We compared the relative abundance of tree palms across biogeographical realms and tested for associations with palaeoclimate stability, current climate, edaphic conditions and metrics of forest structure.ResultsOn average, the relative abundance of tree palms was more than five times larger between Neotropical locations and other biogeographical realms. Tree palms were absent in most locations outside the Neotropics but present in >80% of Neotropical locations. The relative abundance of tree palms was more strongly associated with local conditions (e.g., higher mean annual precipitation, lower soil fertility, shallower water table and lower plot mean wood density) than metrics of long‐term climate stability. Life‐form diversity also influenced the patterns; palm assemblages outside the Neotropics comprise many non‐tree (e.g., climbing) palms. Finally, we show that tree palms can influence estimates of above‐ground biomass, but the magnitude and direction of the effect require additional work.ConclusionsTree palms are not only quintessentially tropical, but they are also overwhelmingly Neotropical. Future work to understand the contributions of tree palms to biomass estimates and carbon cycling will be particularly crucial in Neotropical forests.
|
|
| 17. |
- Ohshiro, Kazufumi, et al.
(författare)
-
Acetylation-dependent oncogenic activity of metastasis-associated protein 1 co-regulator.
- 2010
-
Ingår i: EMBO reports. - : EMBO. - 1469-3178 .- 1469-221X. ; 11:9, s. 691-7
-
Tidskriftsartikel (refereegranskat)abstract
- High expression of metastasis-associated protein 1 co-regulator (MTA1), a component of the nuclear remodelling and histone deacetylase complex, has been associated with human tumours. However, the precise role of MTA1 in tumorigenesis remains unknown. In this study, we show that induced levels of MTA1 are sufficient to transform Rat1 fibroblasts and that the transforming potential of MTA1 is dependent on its acetylation at Lys626. Underlying mechanisms of MTA1-mediated transformation include activation of the Ras-Raf pathway by MTA1 but not by acetylation-inactive MTA1; this was due to the repression of Galphai2 transcription, which negatively influences Ras activation. We observed that acetylated MTA1-histone deacetylase (HDAC) interaction was required for the recruitment of the MTA1-HDAC complex to the Galphai2 regulatory element and consequently for the repression of Galphai2 transcription and expression leading to activation of the Ras-Raf pathway. The findings presented in this study provide for the first time--to the best of our knowledge--evidence of acetylation-dependent oncogenic activity of a cancer-relevant gene product.
|
|
| 18. |
- Peng, Xinxia, et al.
(författare)
-
The draft genome sequence of the ferret (Mustela putorius furo) facilitates study of human respiratory disease
- 2014
-
Ingår i: Nature Biotechnology. - : Springer Science and Business Media LLC. - 1087-0156 .- 1546-1696. ; 32:12, s. 1250-U114
-
Tidskriftsartikel (refereegranskat)abstract
- The domestic ferret (Mustela putorius furo) is an important animal model for multiple human respiratory diseases. It is considered the 'gold standard' for modeling human influenza virus infection and transmission(1-)4. Here we describe the 2.41 Gb draft genome assembly of the domestic ferret, constituting 2.28 Gb of sequence plus gaps. We annotated 19,910 protein-coding genes on this assembly using RNA-seq data from 21 ferret tissues. We characterized the ferret host response to two influenza virus infections by RNA-seq analysis of 42 ferret samples from influenza time-course data and showed distinct signatures in ferret trachea and lung tissues specific to 1918 or 2009 human pandemic influenza virus infections. Using microarray data from 16 ferret samples reflecting cystic fibrosis disease progression, we showed that transcriptional changes in the CFTR-knockout ferret lung reflect pathways of early disease that cannot be readily studied in human infants with cystic fibrosis disease.
|
|
| 19. |
- Stenman, U H, et al.
(författare)
-
Summary report of the TD-3 workshop: characterization of 83 antibodies against prostate-specific antigen
- 1999
-
Ingår i: Tumor Biology. - : Springer Science and Business Media LLC. - 1423-0380 .- 1010-4283. ; 20:Suppl. 1, s. 1-12
-
Tidskriftsartikel (refereegranskat)abstract
- Twelve research groups participated in the ISOBM TD-3 Workshop in which the reactivity and specificity of 83 antibodies against prostate-specific antigen (PSA) were investigated. Using a variety of techniques including cross-inhibition assays, Western blotting, BIAcore, immunoradiometric assays and immunohistochemistry, the antibodies were categorized into six major groups which formed the basis for mapping onto two- and three-dimensional (2-D and 3-D) models of PSA. The overall findings of the TD-3 Workshop are summarized in this report. In agreement with all participating groups, three main antigenic domains were identified: free PSA-specific epitopes located in or close to amino acids 86-91; discontinuous epitopes specific for PSA without human kallikrein (hK2) cross-reactivity located at or close to amino acids 158-163; and continuous or linear epitopes shared between PSA and hK2 located close to amino acids 3-11. In addition, several minor and partly overlapping domains were also identified. Clearly, the characterization of antibodies from this workshop and the location of their epitopes on the 3-D model of PSA illustrate the importance of selecting appropriate antibody pairs for use in immunoassays. It is hoped that these findings and the epitope nomenclature described in this TD-3 Workshop are used as a standard for future evaluation of anti-PSA antibodies.
|
|
| 20. |
|
|
| 21. |
- Aljabali, Alaa A. A., et al.
(författare)
-
The viral capsid as novel nanomaterials for drug delivery
- 2021
-
Ingår i: Future Science OA. - : Future Science Ltd. - 2056-5623. ; 7:9
-
Forskningsöversikt (refereegranskat)abstract
- The purpose of this review is to highlight recent scientific developments and provide an overview of virus self-assembly and viral particle dynamics. Viruses are organized supramolecular structures with distinct yet related features and functions. Plant viruses are extensively used in biotechnology, and virus-like particulate matter is generated by genetic modification. Both provide a material-based means for selective distribution and delivery of drug molecules. Through surface engineering of their capsids, virus-derived nanomaterials facilitate various potential applications for selective drug delivery. Viruses have significant implications in chemotherapy, gene transfer, vaccine production, immunotherapy and molecular imaging. Lay abstract: The purpose of this review is to highlight recent scientific developments and provide an overview of virus self-assembly and viral particle dynamics. Viruses are organized supramolecular structures with distinct yet related features and functions. Plant viruses are extensively used in biotechnology, and virus-like particulate matter is generated by genetic modification. Both provide a material-based means for selective distribution and delivery of drug molecules. Through surface engineering of their capsids, virus-derived nanomaterials facilitate various potential applications for selective drug delivery. Viruses have significant implications in chemotherapy, gene transfer, vaccine production, immunotherapy and molecular imaging. Here we performed a comprehensive database search to review findings in this area, demonstrating that viral nanostructures possess unique properties that make them ideal for applications in diagnostics, cell labeling, contrasting agents and drug delivery structures.
|
|
| 22. |
- Dawson, George J., et al.
(författare)
-
Prevalence studies of GB virus-C infection using reverse transcriptase-polymerase chain reaction
- 1996
-
Ingår i: Journal of Medical Virology. - 1096-9071. ; 50:1, s. 97-103
-
Tidskriftsartikel (refereegranskat)abstract
- Among the three recently described GB viruses (GBV-A, GBV-B, and GBV-C), only GBV-C has been linked to cryptogenic hepatitis in man. Because of the limited utility of currently available research tests to determine antibody response to GBV-C proteins, the prevalence of GBV-C RNA in human sera was studied using reverse transcription-polymerase chain reaction (RT-PCR). The prevalence of GBV-C is higher among volunteer blood donors with elevated serum alanine aminotransferase (ALT) levels (3.9%) than among volunteer blood donors with normal ALT levels (0.8%). Higher rates were also noted among commercial blood donors (12.9%) and intravenous drug users (16.0%). GBV-C was frequently detected in residents of West Africa, where the prevalence was > 10% in most age groups. Approximately 20% of patients diagnosed with either acute or chronic hepatitis C virus (HCV) were found to be positive for GBV-C RNA. In addition, GBV-C RNA sequences were detected in individuals diagnosed with non-A-E hepatitis, with clinical courses ranging from mild disease to fulminant hepatitis. Fourteen of sixteen subjects with or without clinically apparent hepatitis were positive for GBV-C RNA more than 1 year after the initial positive result.
|
|
| 23. |
|
|
| 24. |
|
|
| 25. |
- Ellinghaus, David, et al.
(författare)
-
Association between variants of PRDM1 and NDP52 and Crohn's disease, based on exome sequencing and functional studies
- 2013
-
Ingår i: Gastroenterology. - : Elsevier BV. - 0016-5085 .- 1528-0012. ; 145:2, s. 339-347
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND & AIMS: Genome-wide association studies (GWAS) have identified 140 Crohn's disease (CD) susceptibility loci. For most loci, the variants that cause disease are not known and the genes affected by these variants have not been identified. We aimed to identify variants that cause CD through detailed sequencing, genetic association, expression, and functional studies.METHODS: We sequenced whole exomes of 42 unrelated subjects with CD and 5 healthy subjects (controls) and then filtered single nucleotide variants by incorporating association results from meta-analyses of CD GWAS and in silico mutation effect prediction algorithms. We then genotyped 9348 subjects with CD, 2868 subjects with ulcerative colitis, and 14,567 control subjects and associated variants analyzed in functional studies using materials from subjects and controls and in vitro model systems.RESULTS: We identified rare missense mutations in PR domain-containing 1 (PRDM1) and associated these with CD. These mutations increased proliferation of T cells and secretion of cytokines on activation and increased expression of the adhesion molecule L-selectin. A common CD risk allele, identified in GWAS, correlated with reduced expression of PRDM1 in ileal biopsy specimens and peripheral blood mononuclear cells (combined P = 1.6 x 10(-8)). We identified an association between CD and a common missense variant, Val248Ala, in nuclear domain 10 protein 52 (NDP52) (P = 4.83 x 10(-9)). We found that this variant impairs the regulatory functions of NDP52 to inhibit nuclear factor kappa B activation of genes that regulate inflammation and affect the stability of proteins in Toll-like receptor pathways.CONCLUSIONS: We have extended the results of GWAS and provide evidence that variants in PRDM1 and NDP52 determine susceptibility to CD. PRDM1 maps adjacent to a CD interval identified in GWAS and encodes a transcription factor expressed by T and B cells. NDP52 is an adaptor protein that functions in selective autophagy of intracellular bacteria and signaling molecules, supporting the role of autophagy in the pathogenesis of CD.
|
|
| 26. |
- Flowers, Sarah A., et al.
(författare)
-
Decrease of core 2 O-glycans on synovial lubricin in osteoarthritis reduces galectin-3 mediated crosslinking
- 2020
-
Ingår i: Journal of Biological Chemistry. - 0021-9258 .- 1083-351X. ; 295:47, s. 16023-16036
-
Tidskriftsartikel (refereegranskat)abstract
- The synovial fluid glycoprotein lubricin (also known as proteoglycan 4) is a mucin-type O-linked glycosylated biological lubricant implicated to be involved in osteoarthritis (OA) development. Lubricin's ability to reduce friction is related to its glycosylation consisting of sialylated and unsialylated Tn-antigens and core 1 and core 2 structures. The glycans on lubricin have also been suggested to be involved in crosslinking and stabilization of the lubricating superficial layer of cartilage by mediating interaction between lubricin and galectin-3. However, with the spectrum of glycans being found on lubricin, the glycan candidates involved in this interaction were unknown. Here, we confirm that the core 2 O-linked glycans mediate this lubricin-galectin-3 interaction, shown by surface plasmon resonance data indicating that recombinant lubricin (rhPRG4) devoid of core 2 structures did not bind to recombinant galectin-3. Conversely, transfection of Chinese hamster ovary cells with the core 2 GlcNAc transferase acting on a mucin-type O-glycoprotein displayed increased galectin-3 binding. Both the level of galectin-3 and the galectin-3 interactions with synovial lubricin were found to be decreased in late-stage OA patients, coinciding with an increase in unsialylated core 1 O-glycans (T-antigens) and Tn-antigens. These data suggest a defect in crosslinking of surface-active molecules in OA and provide novel insights into OA molecular pathology.
|
|
| 27. |
- Frank, Stefan, et al.
(författare)
-
yylncT Defines a Class of Divergently Transcribed lncRNAs and Safeguards the T-mediated Mesodermal Commitment of Human PSCs.
- 2019
-
Ingår i: Cell stem cell. - : Elsevier BV. - 1875-9777 .- 1934-5909. ; 24:2
-
Tidskriftsartikel (refereegranskat)abstract
- Human protein-coding genes are often accompanied by divergently transcribed non-coding RNAs whose functions, especially in cell fate decisions, are poorly understood. Using an hESC-based cardiac differentiation model, we define a class of divergent lncRNAs, termed yin yang lncRNAs (yylncRNAs), that mirror the cell-type-specific expression pattern of their protein-coding counterparts. yylncRNAs arepreferentially encoded from the genomic loci ofkey developmental cell fate regulators. Most yylncRNAs are spliced polyadenylated transcripts showing comparable expression patterns invivo inmouse and in human embryos. Signifying theirdevelopmental function, the key mesoderm specifier BRACHYURY (T) is accompanied by yylncT, whichlocalizes to the active T locus during mesoderm commitment. yylncT binds the de novo DNA methyltransferase DNMT3B, and its transcript is required for activation of the T locus, with yylncTdepletion specifically abolishing mesodermal commitment. Collectively, we report a lncRNA-mediated regulatory layer safeguarding embryonic cell fate transitions.
|
|
| 28. |
- Fuks, Jonas M, et al.
(författare)
-
GABAergic Signaling Is Linked to a Hypermigratory Phenotype in Dendritic Cells Infected by Toxoplasma gondii
- 2012
-
Ingår i: PLoS pathogens. - : Public Library of Science (PLoS). - 1553-7374. ; 8:12, s. e1003051-
-
Tidskriftsartikel (refereegranskat)abstract
- During acute infection in human and animal hosts, the obligate intracellular protozoan Toxoplasma gondii infects a variety of cell types, including leukocytes. Poised to respond to invading pathogens, dendritic cells (DC) may also be exploited by T. gondii for spread in the infected host. Here, we report that human and mouse myeloid DC possess functional γ-aminobutyric acid (GABA) receptors and the machinery for GABA biosynthesis and secretion. Shortly after T. gondii infection (genotypes I, II and III), DC responded with enhanced GABA secretion in vitro. We demonstrate that GABA activates GABA(A) receptor-mediated currents in T. gondii-infected DC, which exhibit a hypermigratory phenotype. Inhibition of GABA synthesis, transportation or GABA(A) receptor blockade in T. gondii-infected DC resulted in impaired transmigration capacity, motility and chemotactic response to CCL19 in vitro. Moreover, exogenous GABA or supernatant from infected DC restored the migration of infected DC in vitro. In a mouse model of toxoplasmosis, adoptive transfer of infected DC pre-treated with GABAergic inhibitors reduced parasite dissemination and parasite loads in target organs, e.g. the central nervous system. Altogether, we provide evidence that GABAergic signaling modulates the migratory properties of DC and that T. gondii likely makes use of this pathway for dissemination. The findings unveil that GABA, the principal inhibitory neurotransmitter in the brain, has activation functions in the immune system that may be hijacked by intracellular pathogens.
|
|
| 29. |
- Ganji, Suresh, 1984-, et al.
(författare)
-
Asymmetric Synthesis of Oxygenated Monoterpenoids of Importance for Bark Beetle Ecology
- 2020
-
Ingår i: Journal of Natural Products. - : American Chemical Society (ACS). - 0163-3864 .- 1520-6025. ; 83:11, s. 3332-3337
-
Tidskriftsartikel (refereegranskat)abstract
- Herein we report the asymmetric syntheses of a number of oxygenated terpenoids that are of importance in the chemical ecology of bark beetles. These are pinocamphones, isopinocamphones, pinocarvones, and 4-thujanols (= sabinene hydrates). The camphones were synthesized from isopinocampheol, the pinocarvones from beta-pinene, and the thujanols from sabinene. The NMR spectroscopic data, specific rotations, and elution orders of their stereoisomers on a chiral GC-phase (beta-cyclodextrin) are also reported. This enables facile synthesis of pure compounds for biological activity studies and identification of stereoisomers in mixed natural samples.
|
|
| 30. |
|
|
| 31. |
- Jami, Junaid, et al.
(författare)
-
First-principles investigation of the structure, stability, and magnetic properties of the Heusler alloy Fe2MnSn
- 2023
-
Ingår i: Physical Review B. - : American Physical Society (APS). - 2469-9950 .- 2469-9969. ; 108:5
-
Tidskriftsartikel (refereegranskat)abstract
- Considering the vast compositional space of Heusler alloys, first-principles-based calculations are ideally suitable for predicting the ground state structure and tailoring the magnetic properties of these alloys. We perform density-functional-theory-based calculations for step-by-step identification of the most stable phase of Fe2MnSn, taking into account all the different structural phases exhibited for this alloy (viz., cubic L21, cubic XA, tetragonal L21, tetragonal XA, and hexagonal D019), followed by the calculations of magnetic properties. We identify the magnetic ground state of each phase and then the most stable structural phase by taking into account electronic and geometric relaxation, spin polarization, and vibrational free energy contributions. The ferromagnetic configuration of all the phases is found to be energetically the most favorable magnetic state, while the ferromagnetic hexagonal phase is identified to be the stable structural phase of Fe2MnSn, with a sizable magnetization of 6.45 mu B/f.u. Furthermore, the exchange interactions in the hexagonal phase are calculated using the Liechtenstein approach, and this phase shows a high Curie temperature of 729 K attributed to the strong Fe-Fe exchange coupling. The stable hexagonal phase reveals an in-plane magnetic anisotropy of -1.24 MJ/m3. The large magnetization and high Curie temperature of this phase can make this material suitable for desired magnetic applications. Computational investigations such as this one, in addition to being a cost effective pathway, may provide many valuable insights for the experimental realization and application of a given alloy.
|
|
| 32. |
- Kalra, Hina, et al.
(författare)
-
Vesiclepedia : a compendium for extracellular vesicles with continuous community annotation
- 2012
-
Ingår i: PLoS biology. - : Public library of science. - 1544-9173 .- 1545-7885. ; 10:12, s. e1001450-
-
Tidskriftsartikel (refereegranskat)abstract
- Extracellular vesicles (EVs) are membraneous vesicles released by a variety of cells into their microenvironment. Recent studies have elucidated the role of EVs in intercellular communication, pathogenesis, drug, vaccine and gene-vector delivery, and as possible reservoirs of biomarkers. These findings have generated immense interest, along with an exponential increase in molecular data pertaining to EVs. Here, we describe Vesiclepedia, a manually curated compendium of molecular data (lipid, RNA, and protein) identified in different classes of EVs from more than 300 independent studies published over the past several years. Even though databases are indispensable resources for the scientific community, recent studies have shown that more than 50% of the databases are not regularly updated. In addition, more than 20% of the database links are inactive. To prevent such database and link decay, we have initiated a continuous community annotation project with the active involvement of EV researchers. The EV research community can set a gold standard in data sharing with Vesiclepedia, which could evolve as a primary resource for the field.
|
|
| 33. |
- Kumar, Archana Vijaya, et al.
(författare)
-
HS3ST2 modulates breast cancer cell invasiveness via MAP kinase- and Tcf4 (Tcf7l2)-dependent regulation of protease and cadherin expression
- 2014
-
Ingår i: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 135:11, s. 2579-2592
-
Tidskriftsartikel (refereegranskat)abstract
- Heparan sulfate 3-O-sulfotransferase 2 (HS3ST2), an enzyme mediating 3-O-sulfation of heparan sulfate (HS), is silenced by hypermethylation in breast cancer. As HS has an important co-receptor function for numerous signal transduction pathways, the phenotypical changes due to HS3ST2 reexpression were investigated in vitro using high and low invasive breast cancer cell lines. Compared to controls, highly invasive HS3ST2-expressing MDA-MB-231 cells showed enhanced Matrigel invasiveness, transendothelial migration and motility. Affymetrix screening and confirmatory real-time PCR and Western blotting analysis revealed increased expression of several matrix metalloproteinases, cadherin-11, E-cadherin and CEACAM-1, while protease inhibitor and annexin A10 expression were decreased. Low invasive HS3ST2 -expressing MCF-7 cells became even less invasive, with no change in gelatinolytic MMP activity. HS3ST2 expression increased HS-dependent basal and FGF2-specific signaling through the constitutively active p44/42 MAPK pathway in MDA-MB-231 cells. Increased MAPK activation was accompanied by upregulation of beta-catenin in MDA-MB-231, and of the transcription factor Tcf4 in both cell lines. Dysregulation of Tcf4-regulated ion transporters and increased cytosolic acidification were observed in HS3ST2-expressing MDA-MB-231 cells, which is a possible underlying cause of increased chemosensitivity towards doxorubicine and paclitaxel in these cells. This study provides the first in vitro evidence of the involvement of HS3ST2 in breast cancer cell invasion and chemosensitivity.
|
|
| 34. |
- Kuo, Chao-Chung, et al.
(författare)
-
Detection of RNA-DNA binding sites in long noncoding RNAs.
- 2019
-
Ingår i: Nucleic acids research. - : Oxford University Press (OUP). - 1362-4962 .- 0305-1048. ; 47:6
-
Tidskriftsartikel (refereegranskat)abstract
- Long non-coding RNAs (lncRNAs) can act as scaffolds that promote the interaction of proteins, RNA, and DNA. There is increasing evidence of sequence-specific interactions of lncRNAs with DNA via triple-helix (triplex) formation. This process allows lncRNAs to recruit protein complexes to specific genomic regions and regulate gene expression. Here we propose a computational method called Triplex Domain Finder (TDF) to detect triplexes and characterize DNA-binding domains and DNA targets statistically. Case studies showed that this approach can detect the known domains of lncRNAs Fendrr, HOTAIR and MEG3. Moreover, we validated a novel DNA-binding domain in MEG3 by a genome-wide sequencing method. We used TDF to perform a systematic analysis of the triplex-forming potential of lncRNAs relevant to human cardiac differentiation. We demonstrated that the lncRNA with the highest triplex-forming potential, GATA6-AS, forms triple helices in the promoter of genes relevant to cardiac development. Moreover, down-regulation of GATA6-AS impairs GATA6 expression and cardiac development. These data indicate the unique ability of our computational tool to identify novel triplex-forming lncRNAs and their target genes.
|
|
| 35. |
- Langdahl, Bente L., et al.
(författare)
-
A 24-Month Study Evaluating the Efficacy and Safety of Denosumab for the Treatment of Men With Low Bone Mineral Density : Results From the ADAMO Trial
- 2015
-
Ingår i: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 100:4, s. 1335-1342
-
Tidskriftsartikel (refereegranskat)abstract
- Context: One in 4 men in the United States aged >50 years will have an osteoporosis-related fracture. Fewer data are available on osteoporosis treatment in men than in women. Objective: The purpose of this study was to evaluate denosumab therapy in men with low bone mineral density (BMD). Design: This was a phase 3 study with 2 treatment periods: a previously reported 12-month double-blind, placebo-controlled phase and a 12-month open-label phase. Setting: This was a multicenter study conducted in North America and Europe. Participants: A total of 228 men entered the open-label phase and 219 completed the study. Intervention: Men from the original denosumab (long-term) and placebo (crossover) groups received 60 mg of denosumab sc every 6 months. Main Outcome Measures: BMD, serum collagen type I C-telopeptide, and safety were measured. Results: During the open-label phase, continued BMD increases occurred with long-term denosumab treatment (2.2% lumbar spine, 0.9% total hip, 1.3% femoral neck, 1.3% trochanter, and 0.2% 1/3 radius), resulting in cumulative 24-month gains from baseline of 8.0%, 3.4%, 3.4%, 4.6%, and 0.7%, respectively (all P < .01). The crossover group showed BMD gains after 12 months of denosumab treatment similar to those of the long-term denosumab group during the first treatment year. Significant reductions in serum collagen type I C-teleopeptide were observed after denosumab administration. Adverse event rates were similar between groups, and no new safety signals were identified. Conclusions: In men with low BMD, denosumab treatment for a second year continued to increase BMD, maintained reductions in bone resorption, and was well tolerated. BMD increased in men initiating denosumab during the second year. These effects were similar to those previously seen in postmenopausal women with osteoporosis and in men with prostate cancer receiving androgen deprivation therapy.
|
|
| 36. |
|
|
| 37. |
- Nagaraju, D H., et al.
(författare)
-
Green Chemistry Route to the Synthesis of Palladium Nanoparticles on Reduced Graphene Oxide for Ethanol Fuel Cells Applications
- 2012
-
Ingår i: ECS ELECTROCHEMISTRY LETTERS. - : Electrochemical Society. - 2162-8726 .- 2162-8734. ; 1:3, s. F21-F23
-
Tidskriftsartikel (refereegranskat)abstract
- In this article, we have demonstrated the synthesis of palladium nanoparticles decorated on reduced graphene oxide (RGO-Pd NPs) film via green chemistry route, one pot electrochemical reduction of graphene oxide and palladium ions without using any chemical reducing agents. Cyclic voltammetry in acid medium shows the characteristic nanosized palladium nanoparticles. The RGO-Pd NPs poses very high electrochemically active surface area and shows good catalytic properties for the elctrooxidation of ethanol in alkaline medium.
|
|
| 38. |
- Orwoll, Eric, et al.
(författare)
-
A Randomized, Placebo-Controlled Study of the Effects of Denosumab for the Treatment of Men with Low Bone Mineral Density
- 2012
-
Ingår i: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 97:9, s. 3161-3169
-
Tidskriftsartikel (refereegranskat)abstract
- Context: Men with low bone mineral density (BMD) were treated with denosumab.Objective: Our objective was to investigate the effects of denosumab compared with placebo in men with low BMD after 1 yr of treatment.Design, Subjects, and Intervention: This was a placebo-controlled, phase 3 study to investigate the efficacy and safety of denosumab 60 mg every 6 months vs. placebo in men with low BMD.Main Outcome Measure: The primary endpoint was the percent change from baseline in lumbar spine (LS) BMD at month 12.Results: Of the 242 randomized subjects (mean age 65 yr), 228 (94.2%) completed 1 yr of denosumab therapy. After 12 months, denosumab resulted in BMD increases of 5.7% at the LS, 2.4% at the total hip, 2.1% at the femoral neck, 3.1% at the trochanter, and 0.6% at the one third radius (adjusted P <= 0.0144 for BMD percent differences at all sites compared with placebo). Sensitivity analyses done by controlling for baseline covariates (such as baseline testosterone levels, BMD T-scores, and 10-yr osteoporotic fracture risk) demonstrated that the results of the primary endpoint were robust. Subgroup analyses indicate that treatment with denosumab was effective across a spectrum of clinical situations. Treatment with denosumab significantly reduced serum CTX levels at d 15 (adjusted P < 0.0001). The incidence of adverse events was similar between groups.Conclusions: One year of denosumab therapy in men with low BMD was well tolerated and resulted in a reduction in bone resorption and significant increases in BMD at all skeletal sites assessed.
|
|
| 39. |
- Rani, D., et al.
(författare)
-
Spin-gapless semiconductors: Fundamental and applied aspects
- 2020
-
Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 128:22
-
Tidskriftsartikel (refereegranskat)abstract
- Spin-gapless semiconductors (SGSs) are new states of quantum matter, which are characterized by a unique spin-polarized band structure. Unlike conventional semiconductors or half-metallic ferromagnets, they carry a finite bandgap for one spin channel and a close (zero) gap for the other and thus are useful for tunable spin transport applications. It is one of the latest classes of materials considered for spintronic devices. A few of the several advantages of SGS include (i) a high Curie temperature, (ii) a minimal amount of energy required to excite electrons from the valence to conduction band due to zero gap, and (iii) the availability of both charge carriers, i.e., electrons as well as holes, which can be 100% spin-polarized simultaneously. In this perspective article, the theoretical foundation of SGS is first reviewed followed by experimental advancements on various realistic materials. The first band structure of SGS was reported in bulk Co-doped PbPdO 2, using first-principles calculations. This was followed by a large number of ab initio simulation reports predicting SGS nature in different Heusler alloy systems. The first experimental realization of SGS was made in 2013 in a bulk inverse Heusler alloy, Mn 2CoAl. In terms of material properties, SGS shows a few unique features such as nearly temperature-independent conductivity ( sigma) and carrier concentration, a very low temperature coefficient of resistivity, a vanishingly small Seebeck coefficient, quantum linear magnetoresistance in a low temperature range, etc. Later, several other systems, including 2-dimensional materials, were reported to show the signature of SGS. There are some variants of SGSs that can show a quantum anomalous Hall effect. These SGSs are classic examples of topological (Chern) insulators. In the later part of this article, we have touched upon some of these aspects of SGS or the so-called Dirac SGS systems as well. In general, SGSs can be categorized into four different types depending on how various bands corresponding to two different spin channels touch the Fermi level. The hunt for these different types of SGS materials is growing very fast. Some of the recent progress along this direction is also discussed.
|
|
| 40. |
- Sanyal, Biplab, et al.
(författare)
-
Ferromagnetism in Mn doped half-Heusler NiTiSn : Theory and experiment
- 2006
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 89:21, s. 212502-
-
Tidskriftsartikel (refereegranskat)abstract
- In this letter, the authors show by ab initio density functional calculations and experiments that Mn doped semiconducting half-Heusler compound NiTiSn can exhibit room-temperature ferromagnetism. Curie temperatures were calculated by Monte Carlo simulations using calculated Heisenberg exchange parameters in an ab initio Green's function approach. The calculated temperature exceeds room temperature for a Mn doping concentration of 22%. Magnetic measurements confirm the presence of possible intrinsic ferromagnetism in these systems. This brings up the possibility of considering this system as a potential candidate for use in room-temperature spintronic devices.
|
|
| 41. |
- Sen, Amrik, et al.
(författare)
-
Dynamic space warping of strokes for recognition of online handwritten characters
- 2009
-
Ingår i: International journal of pattern recognition and artificial intelligence. - 0218-0014. ; 23:5, s. 925-943
-
Tidskriftsartikel (refereegranskat)abstract
- This paper suggests a scheme for classifying online handwritten characters, based on dynamic space warping of strokes within the characters. A method for segmenting components into strokes using velocity profiles is proposed. Each stroke is a simple arbitrary shape and is encoded using three attributes. Correspondence between various strokes is established using Dynamic Space Warping. A distance measure which reliably differentiates between two corresponding simple shapes (strokes) has been formulated thus obtaining a perceptual distance measure between any two characters. Tests indicate an accuracy of over 85% on two different datasets of characters.
|
|
| 42. |
- Suresh, K.G., et al.
(författare)
-
Tourism, trade, and economic growth in India : a frequency-domain analysis of causality
- 2018
-
Ingår i: Anatolia. - : Routledge. - 1303-2917 .- 2156-6909. ; 29:3, s. 319-325
-
Tidskriftsartikel (refereegranskat)abstract
- We examine causal relationships among the macroeconomic entities tourism and output dynamics in India, using the frequency–domain causality approach. Our results show that there is a bidirectional causality between openness and tourism as well as between output and tourism, at various frequency bands. Hence, this study suggests a multiplier effect of tourism on the Indian economy.
|
|
| 43. |
|
|
| 44. |
- Tiwari, Suresh, et al.
(författare)
-
Assessment of PM2.5 and PM10 over Guwahati in Brahmaputra River Valley : Temporal evolution, source apportionment and meteorological dependence
- 2017
-
Ingår i: Atmospheric Pollution Research. - : Elsevier BV. - 1309-1042. ; 8:1, s. 13-28
-
Tidskriftsartikel (refereegranskat)abstract
- Temporal evolution, source apportionment and transport pathways of particulate matter (PM2.5 and PM10) are analysed over Guwahati, located in the Brahmaputra River Valley (BRV), as a function of meteorological dynamics. During the study period (July 2013-June 2014), the mean PM2.5 and PM10 mass concentrations were found to be 52 +/- 37 and 91 +/- 60 mu g m (-3), respectively, both exhibiting higher concentrations during DecembereMarch and very low during summer. The annual mean ratio of PM2.5/ PM10 was 0.57 +/- 0.11, varying from 0.24 to 0.86, suggesting dominance of anthropogenic vs natural emissions during winter and spring, respectively. Diurnal variation reveals higher PM concentrations during morning (similar to 9: 00 local time (LT)) and evening (similar to 23: 00 LT) and lowest around similar to 14: 00 to 17: 00 LT due to influence of dilution processes and higher mixing-layer height over the region. Bivariate plots and Conditional Bivariate Probability Function (CBPF) analysis showed that the highest PM2.5 and PM10 concentrations are mostly associated with weak northwestern winds (< 1.5 ms (- 1)) in all seasons except spring, when the highest PM10 are for southwestern winds above 4-6 ms(- 1), indicating dust transport from SW Asia. Analysis reveals that the local emissions, transported aerosols, along with seasonallychanged air masses, meteorology and boundary-layer dynamics control the concentrations, evolution and fractions of PM over BRV. The turbid air masses transported over Guwahati mostly from western and southwestern directions contribute to higher PM concentrations, either carrying anthropogenic pollution from Indo-Gangetic Plains or locally and LRT dust from BRV and western India, respectively.
|
|
| 45. |
- Venkatesh, L., et al.
(författare)
-
Microstructural response of various chromium carbide based coatings to erosion and nano impact testing
- 2017
-
Ingår i: Wear. - : Elsevier BV. - 0043-1648 .- 1873-2577. ; 386-387, s. 72-79
-
Tidskriftsartikel (refereegranskat)abstract
- In this study, we demonstrate the microstructure dependency of erosion behaviour of laser clad, detonation sprayed and atmospheric plasma sprayed chromium carbide based coatings. The final chromium carbide content in all the coatings was a strong function of rapid solidification rate associated with the processes. In the laser clad coating majority of the chromium carbides re-solidified while in the thermally sprayed coatings chromium carbide re-solidification was hindered to a large extent. Hence, the final chromium carbide content in the thermally sprayed coating decreased with increased extent of particle melting during spraying. Decarburisation and oxidation during thermal spraying lead to the formation of chromium carbides with lower carbon content and chromium oxide(s). Laser clad and detonation sprayed coatings, with higher chromium carbide content, showed lower erosion rates and exhibited fewer brittle erosion events. Embrittlement due to excessive dissolution of chromium carbides into the matrix and poor splat bonding were found to be the reasons for higher erosion rate of the plasma sprayed coating. Scanning electron microscopy and quantification of single erodent impact events clearly established ductile material removal in the laser clad and detonation sprayed coating and brittle material removal in the plasma sprayed coating as the dominant mechanism(s). A good agreement was found between solid particle erosion testing and nano impact testing results.
|
|
| 46. |
- Vernet, Nicolas, et al.
(författare)
-
Experimental determination of the permeability of engineering textiles : Benchmark II
- 2014
-
Ingår i: Composites. Part A, Applied science and manufacturing. - : Elsevier Ltd. - 1359-835X .- 1878-5840. ; 61, s. 172-184
-
Tidskriftsartikel (refereegranskat)abstract
- In this second international permeability benchmark, the in-plane permeability values of a carbon fabric were studied by twelve research groups worldwide. One participant also investigated the deformation of the tested carbon fabric. The aim of this work was to obtain comparable results in order to make a step toward standardization of permeability measurements. Unidirectional injections were thus conducted to determine the unsaturated in-plane permeability tensor of the fabric. Procedures used by participants were specified in the guidelines defined for this benchmark. Participants were asked to use the same values for parameters such as fiber volume fraction, injection pressure and fluid viscosity to minimize sources of scatter. The comparison of the results from each participant was encouraging. The scatter between data obtained while respecting the guidelines was below 25%. However, a higher dispersion was observed when some parameters differed from the recommendations of this exercise.
|
|
| 47. |
|
|
