44 research outputs found
Application of Nanomaterial to Stabilize a Weak Soil
There are little investigations in the literature on the nanotechnology\u27s application in the geothecnical field. Since, lots of soil and rock minerals are nanomaterial and their chemical reactions are in the nano-scale, there is a great potential for the use of this technology in different fields of geothecnical engineering such as seepage, grouting, soil stabilization and etc. In this study the stabilization of a weak soil was investigated using nanomaterial. The weak soil was obtained from Boodian Road in North of Iran and classified as low plasticity clay. Fifty CBR tests were conducted in this study. At the first step the effect of lime on the stabilization of the weak soil was investigated. The results proved a little effect of lime in the soil improvement. At the second step, the effect of nano-silica on the stabilization of the soil-lime mixture was studied. The results illustrated the important effect of nano-silica in the soil-lime mixture, in which adding nano-silica increased the CBR strength of the soil and soil-lime mixture up to 21 and 7.5 times respectively. The effects of curing time were also evaluated in this study and the results showed that the CBR strength of the soil-lime mixture increases more rapidly with adding nano-material. In this research, the optimum mixture design for stabilization of the Boodian weak soil was selected as 5% lime and 3% nano-silica added to the soil
Anopheles types and two newly reported species in Bazoft section of Farsan district, Chaharmahal and Bakhtiari province, 1998
In past history, Malaria had been one of the most prevalent native disease in Iran and around the world, that caused a lot of economic and social losses. Some of the anopheles mosquitoes are vectors of Malaria, thus recognizing their species and ecology is important to fight the disease. For this purpose, this research was performed in Bazoft section of Farsan district, which is one of the focuses of Malaria transmission in Chaharmahal and Bakhtiari province. The survey included ten villages over a six months period (May to October 1998). In each village four human places and four animal places and larval habitats were chosen and sampling was performed every fifteen days. Adult mosquitoes were collected by the following methods: Hand catch, Total catch, Night biting and Shelter pit. Larvae were collected by ladling. A total of 1769 adult Anopheles and 2583 larvae were hunted, which belonged to the following species: An.superpictus (67.2%), An.maculipennis (27.2%), An.dthaly (2.4%), An.martri (2.2%), An.claviger (1%). Dthaly and claviger species are reported for the first time in this province. Ecologically, superpictus species was the most prevailed one and dispersed over the entire area. Its maximum activity is during late July to early August, and its seasonal activity begins from the second half of may to late September. In Night biting 55% of this species was hunted from animals. Night biting rate for each individual was 1.1. Based on ELISA test, anthropophilic degree of this species was 28.5%. The sporozoit and oocyst rate was zero. In ovary anatomy, parus rate was 37% and up to 4 dilatations was observed
Superselective Angioembolisation: A Report of Two Rare Cases of Hemoptysis
Superselective bronchial embolization is recently performed with a high success rate. The current study aimed at discussing the procedure and reporting two cases underwent embolization in the Masih-Daneshvari Hospital, a large center for this procedure, in Iran
The Impact of Unemployment, Inflation, and Participation Rate of Women in Labor Market on Divorce Process in Iran
Introduction: The decrease in the marriage rate and the increase in the divorce rate in the last few decades are among the changes in the family institution. The growth of the divorce rate is considered as one of the severe harms of the change in the family institution, which brings with it the expansion of numerous social problems. The status of the economic factor is an influencing factor in divorce because economic disturbances cause quarrels and conflicts between the spouses, other effective factors are social and culture status, etc. There is a parallel relationship between the trends of macroeconomic developments in Iran and the trend of divorce. On the one hand, the unfavorable situation of Iran's macroeconomic variables and on the other hand, the significant increase in the number of divorces in Iran for the past few decades, make it important and necessary to examine the impact of macroeconomic indicators on divorce.
Method: The two-stage least squares method has been used to investigate the effect of economic variables on the divorce process in Iran (1370-1400; 1991-2021). The estimation of the equations has been done in a systematic way. This issue has been analyzed with the help of simultaneity bias and diagonality test. From identification problem over specified equations are confirmed.
Findings: The results show that the effect of unemployment and inflation on divorce is likely to be significant, their coefficients are equal to 0.70 and 0.14. There is a direct relationship between women's participation in the market and the divorce rate; its coefficient is 0.74. Also, there is a simultaneous relationship between the average age of women at first marriage, this variable, and the divorce rate.
Discussion: The economy is an influential factor in couples' decision to get divorced. Therefore, to reduce its rate, the unfavorable situation of economic variables should be improved. The role of women's participation rate in the labor market is significant, but it should be noted that part of it can be due to the previous context. That is, couples have decided to divorce, due to bad economic conditions, social disturbances, personal factors, etc., but women's lack of independence has been an obstacle to divorce, with the woman's employment, ultimately, divorce takes place
Diversidade genética para padrões de gliadinas de raças locais de trigo duro no Noroeste do Iran e no Azerbaijão
The objective of this study was to identify gliadin band patterns and the extent of genetic diversity in durum wheat genotypes from Northwestern Iran and the Republic of Azerbaijan. Gliadins from 46 landraces and four cultivars were evaluated through acid PAGE analyses. Sixty-six polymorphic bands and 81 patterns were identified. Twenty-four different motility bands and 22 patterns were found in the ω gliadin region with 14 polymorph bands and 20 patterns for α and γ gliadins, and 14 bands and 19 different patterns for β gliadins. The combination of these patterns generated 38 and 39 combinations for Gli-1 and Gli-2 loci, respectively. The genetic diversity index (H) was higher for α gliadins (0.924), followed by ω and γ gliadins (0.899 and 0.878, respectively), and for β gliadin patterns (0.866). Extensive polymorphism (H = 0.875) was observed in four gliadin pattern regions, with higher genetic diversity in the Iranian landraces than in the Azerbaijani ones. Each genotype had special identifying patterns in the gliadin acid PAGE analysis, and cluster analysis based on Jaccard's similarity coefficients formed six groups. Gliadin has a simple, repeatable and economic analysis, and can be used in genetic studies.O objetivo deste trabalho foi identificar padrões de bandas de gliadinas e a extenção da variabilidade genética em genótipos de trigo duro do Noroeste do Iran e da República do Azerbaijão. Gliadinas de 46 raças locais e de quatro cultivares foram avaliadas por meio de análises "acid PAGE". Sessenta e seis bandas polimórficas e 81 padrões foram identificados. Foram encontradas 24 bandas de mobilidade e 22 padrões na região da gliadina ω, com 14 bandas polimorfas e 20 padrões para as gliadinas α e γ , e 14 bandas e 19 padrões diferentes para as gliadinas β. A combinação desses padrões gerou 38 e 39 combinações, para os locos Gli-1 e Gli-2, respectivamente. O índice de diversidade genética (H) foi maior para as gliadinas α (0,924), seguidas pelas gliadinas ω e γ (0,899 e 0,878, respectivamente), e pela gliadina β (0,866). Alto polimorfismo (H = 0,875) foi observado em quatro regiões dos padrões de gliadinas obtidos, com diversidade genética maior nas raças locais iranianas do que nas do Azerbaijão. Cada genótipo apresentou padrões de identificação especiais na análise "acid PAGE" de gliadinas, e a análise de agrupamento baseada no coeficiente de similaridade de Jaccard formou seis grupos. A gliadina é de análise simples, repetível e econômica, e pode ser usada em estudos genéticos
Different effects of energy dependent irradiation of red and green lights on proliferation of human umbilical cord matrix-derived mesenchymal cells
Abstract Light-emitting diodes (LED) have recently been
introduced as a potential factor for proliferation of various cell
types in vitro. Nowadays, stem cells are widely used in regenerative
medicine. Human umbilical cord matrix-derived mesenchymal
(hUCM) cells can be more easily isolated and cultured
than adult mesenchymal stem cells. The aim of this
study was to evaluate the effect of red and green lights produced
by LED on the proliferation of hUCM cells. hUCM
cells were isolated from the umbilical cord, and light irradiation
was applied at radiation energies of 0.318, 0.636, 0.954,
1.59, 3.18, 6.36, 9.54, and 12.72 J/cm2. Irradiation of the
hUCM cells shows a significant (p < 0.05) increase in cell
number as compared to controls after 40 h. In addition, cell
proliferation on days 7, 14, and 21 in irradiated groups were
significantly (p< 0.001) higher than that in the non-irradiated
groups. The present study clearly demonstrates the ability of
red and green lights irradiation to promote proliferation of
hUCM cells in vitro. The energy applied to the cells through
LED irradiation is an effective factor with paradoxical alterations.
Green light inserted a much profound effect at special
dosages than red light
Global estimates on the number of people blind or visually impaired by cataract: a meta-analysis from 2000 to 2020
Background: To estimate global and regional trends from 2000 to 2020 of the number of persons visually impaired by cataract and their proportion of the total number of vision-impaired individuals. Methods: A systematic review and meta-analysis of published population studies and gray literature from 2000 to 2020 was carried out to estimate global and regional trends. We developed prevalence estimates based on modeled distance visual impairment and blindness due to cataract, producing location-, year-, age-, and sex-specific estimates of moderate to severe vision impairment (MSVI presenting visual acuity <6/18, ≥3/60) and blindness (presenting visual acuity <3/60). Estimates are age-standardized using the GBD standard population. Results: In 2020, among overall (all ages) 43.3 million blind and 295 million with MSVI, 17.0 million (39.6%) people were blind and 83.5 million (28.3%) had MSVI due to cataract blind 60% female, MSVI 59% female. From 1990 to 2020, the count of persons blind (MSVI) due to cataract increased by 29.7%(93.1%) whereas the age-standardized global prevalence of cataract-related blindness improved by −27.5% and MSVI increased by 7.2%. The contribution of cataract to the age-standardized prevalence of blindness exceeded the global figure only in South Asia (62.9%) and Southeast Asia and Oceania (47.9%). Conclusions: The number of people blind and with MSVI due to cataract has risen over the past 30 years, despite a decrease in the age-standardized prevalence of cataract. This indicates that cataract treatment programs have been beneficial, but population growth and aging have outpaced their impact. Growing numbers of cataract blind indicate that more, better-directed, resources are needed to increase global capacity for cataract surgery.</p
Global age-sex-specific mortality, life expectancy, and population estimates in 204 countries and territories and 811 subnational locations, 1950–2021, and the impact of the COVID-19 pandemic: a comprehensive demographic analysis for the Global Burden of Disease Study 2021
Background: Estimates of demographic metrics are crucial to assess levels and trends of population health outcomes. The profound impact of the COVID-19 pandemic on populations worldwide has underscored the need for timely estimates to understand this unprecedented event within the context of long-term population health trends. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 provides new demographic estimates for 204 countries and territories and 811 additional subnational locations from 1950 to 2021, with a particular emphasis on changes in mortality and life expectancy that occurred during the 2020–21 COVID-19 pandemic period. Methods: 22 223 data sources from vital registration, sample registration, surveys, censuses, and other sources were used to estimate mortality, with a subset of these sources used exclusively to estimate excess mortality due to the COVID-19 pandemic. 2026 data sources were used for population estimation. Additional sources were used to estimate migration; the effects of the HIV epidemic; and demographic discontinuities due to conflicts, famines, natural disasters, and pandemics, which are used as inputs for estimating mortality and population. Spatiotemporal Gaussian process regression (ST-GPR) was used to generate under-5 mortality rates, which synthesised 30 763 location-years of vital registration and sample registration data, 1365 surveys and censuses, and 80 other sources. ST-GPR was also used to estimate adult mortality (between ages 15 and 59 years) based on information from 31 642 location-years of vital registration and sample registration data, 355 surveys and censuses, and 24 other sources. Estimates of child and adult mortality rates were then used to generate life tables with a relational model life table system. For countries with large HIV epidemics, life tables were adjusted using independent estimates of HIV-specific mortality generated via an epidemiological analysis of HIV prevalence surveys, antenatal clinic serosurveillance, and other data sources. Excess mortality due to the COVID-19 pandemic in 2020 and 2021 was determined by subtracting observed all-cause mortality (adjusted for late registration and mortality anomalies) from the mortality expected in the absence of the pandemic. Expected mortality was calculated based on historical trends using an ensemble of models. In location-years where all-cause mortality data were unavailable, we estimated excess mortality rates using a regression model with covariates pertaining to the pandemic. Population size was computed using a Bayesian hierarchical cohort component model. Life expectancy was calculated using age-specific mortality rates and standard demographic methods. Uncertainty intervals (UIs) were calculated for every metric using the 25th and 975th ordered values from a 1000-draw posterior distribution. Findings: Global all-cause mortality followed two distinct patterns over the study period: age-standardised mortality rates declined between 1950 and 2019 (a 62·8% [95% UI 60·5–65·1] decline), and increased during the COVID-19 pandemic period (2020–21; 5·1% [0·9–9·6] increase). In contrast with the overall reverse in mortality trends during the pandemic period, child mortality continued to decline, with 4·66 million (3·98–5·50) global deaths in children younger than 5 years in 2021 compared with 5·21 million (4·50–6·01) in 2019. An estimated 131 million (126–137) people died globally from all causes in 2020 and 2021 combined, of which 15·9 million (14·7–17·2) were due to the COVID-19 pandemic (measured by excess mortality, which includes deaths directly due to SARS-CoV-2 infection and those indirectly due to other social, economic, or behavioural changes associated with the pandemic). Excess mortality rates exceeded 150 deaths per 100 000 population during at least one year of the pandemic in 80 countries and territories, whereas 20 nations had a negative excess mortality rate in 2020 or 2021, indicating that all-cause mortality in these countries was lower during the pandemic than expected based on historical trends. Between 1950 and 2021, global life expectancy at birth increased by 22·7 years (20·8–24·8), from 49·0 years (46·7–51·3) to 71·7 years (70·9–72·5). Global life expectancy at birth declined by 1·6 years (1·0–2·2) between 2019 and 2021, reversing historical trends. An increase in life expectancy was only observed in 32 (15·7%) of 204 countries and territories between 2019 and 2021. The global population reached 7·89 billion (7·67–8·13) people in 2021, by which time 56 of 204 countries and territories had peaked and subsequently populations have declined. The largest proportion of population growth between 2020 and 2021 was in sub-Saharan Africa (39·5% [28·4–52·7]) and south Asia (26·3% [9·0–44·7]). From 2000 to 2021, the ratio of the population aged 65 years and older to the population aged younger than 15 years increased in 188 (92·2%) of 204 nations. Interpretation: Global adult mortality rates markedly increased during the COVID-19 pandemic in 2020 and 2021, reversing past decreasing trends, while child mortality rates continued to decline, albeit more slowly than in earlier years. Although COVID-19 had a substantial impact on many demographic indicators during the first 2 years of the pandemic, overall global health progress over the 72 years evaluated has been profound, with considerable improvements in mortality and life expectancy. Additionally, we observed a deceleration of global population growth since 2017, despite steady or increasing growth in lower-income countries, combined with a continued global shift of population age structures towards older ages. These demographic changes will likely present future challenges to health systems, economies, and societies. The comprehensive demographic estimates reported here will enable researchers, policy makers, health practitioners, and other key stakeholders to better understand and address the profound changes that have occurred in the global health landscape following the first 2 years of the COVID-19 pandemic, and longer-term trends beyond the pandemic
Global age-sex-specific mortality, life expectancy, and population estimates in 204 countries and territories and 811 subnational locations, 1950–2021, and the impact of the COVID-19 pandemic: a comprehensive demographic analysis for the Global Burden of Disease Study 2021
BACKGROUND: Estimates of demographic metrics are crucial to assess levels and trends of population health outcomes. The profound impact of the COVID-19 pandemic on populations worldwide has underscored the need for timely estimates to understand this unprecedented event within the context of long-term population health trends. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 provides new demographic estimates for 204 countries and territories and 811 additional subnational locations from 1950 to 2021, with a particular emphasis on changes in mortality and life expectancy that occurred during the 2020–21 COVID-19 pandemic period. METHODS: 22 223 data sources from vital registration, sample registration, surveys, censuses, and other sources were used to estimate mortality, with a subset of these sources used exclusively to estimate excess mortality due to the COVID-19 pandemic. 2026 data sources were used for population estimation. Additional sources were used to estimate migration; the effects of the HIV epidemic; and demographic discontinuities due to conflicts, famines, natural disasters, and pandemics, which are used as inputs for estimating mortality and population. Spatiotemporal Gaussian process regression (ST-GPR) was used to generate under-5 mortality rates, which synthesised 30 763 location-years of vital registration and sample registration data, 1365 surveys and censuses, and 80 other sources. ST-GPR was also used to estimate adult mortality (between ages 15 and 59 years) based on information from 31 642 location-years of vital registration and sample registration data, 355 surveys and censuses, and 24 other sources. Estimates of child and adult mortality rates were then used to generate life tables with a relational model life table system. For countries with large HIV epidemics, life tables were adjusted using independent estimates of HIV-specific mortality generated via an epidemiological analysis of HIV prevalence surveys, antenatal clinic serosurveillance, and other data sources. Excess mortality due to the COVID-19 pandemic in 2020 and 2021 was determined by subtracting observed all-cause mortality (adjusted for late registration and mortality anomalies) from the mortality expected in the absence of the pandemic. Expected mortality was calculated based on historical trends using an ensemble of models. In location-years where all-cause mortality data were unavailable, we estimated excess mortality rates using a regression model with covariates pertaining to the pandemic. Population size was computed using a Bayesian hierarchical cohort component model. Life expectancy was calculated using age-specific mortality rates and standard demographic methods. Uncertainty intervals (UIs) were calculated for every metric using the 25th and 975th ordered values from a 1000-draw posterior distribution. FINDINGS: Global all-cause mortality followed two distinct patterns over the study period: age-standardised mortality rates declined between 1950 and 2019 (a 62·8% [95% UI 60·5–65·1] decline), and increased during the COVID-19 pandemic period (2020–21; 5·1% [0·9–9·6] increase). In contrast with the overall reverse in mortality trends during the pandemic period, child mortality continued to decline, with 4·66 million (3·98–5·50) global deaths in children younger than 5 years in 2021 compared with 5·21 million (4·50–6·01) in 2019. An estimated 131 million (126–137) people died globally from all causes in 2020 and 2021 combined, of which 15·9 million (14·7–17·2) were due to the COVID-19 pandemic (measured by excess mortality, which includes deaths directly due to SARS-CoV-2 infection and those indirectly due to other social, economic, or behavioural changes associated with the pandemic). Excess mortality rates exceeded 150 deaths per 100 000 population during at least one year of the pandemic in 80 countries and territories, whereas 20 nations had a negative excess mortality rate in 2020 or 2021, indicating that all-cause mortality in these countries was lower during the pandemic than expected based on historical trends. Between 1950 and 2021, global life expectancy at birth increased by 22·7 years (20·8–24·8), from 49·0 years (46·7–51·3) to 71·7 years (70·9–72·5). Global life expectancy at birth declined by 1·6 years (1·0–2·2) between 2019 and 2021, reversing historical trends. An increase in life expectancy was only observed in 32 (15·7%) of 204 countries and territories between 2019 and 2021. The global population reached 7·89 billion (7·67–8·13) people in 2021, by which time 56 of 204 countries and territories had peaked and subsequently populations have declined. The largest proportion of population growth between 2020 and 2021 was in sub-Saharan Africa (39·5% [28·4–52·7]) and south Asia (26·3% [9·0–44·7]). From 2000 to 2021, the ratio of the population aged 65 years and older to the population aged younger than 15 years increased in 188 (92·2%) of 204 nations. INTERPRETATION: Global adult mortality rates markedly increased during the COVID-19 pandemic in 2020 and 2021, reversing past decreasing trends, while child mortality rates continued to decline, albeit more slowly than in earlier years. Although COVID-19 had a substantial impact on many demographic indicators during the first 2 years of the pandemic, overall global health progress over the 72 years evaluated has been profound, with considerable improvements in mortality and life expectancy. Additionally, we observed a deceleration of global population growth since 2017, despite steady or increasing growth in lower-income countries, combined with a continued global shift of population age structures towards older ages. These demographic changes will likely present future challenges to health systems, economies, and societies. The comprehensive demographic estimates reported here will enable researchers, policy makers, health practitioners, and other key stakeholders to better understand and address the profound changes that have occurred in the global health landscape following the first 2 years of the COVID-19 pandemic, and longer-term trends beyond the pandemic. FUNDING: Bill & Melinda Gates Foundation
Global estimates on the number of people blind or visually impaired by cataract : a meta-analysis from 2000 to 2020
DATA AVAILABILITY :
Data sources for the Global Vision Database are listed at the following weblink http://www.anglia.ac.uk/verigbd. Fully disaggregated data is not available publicly due to data sharing agreements with some principal investigators yet requests for summary data can be made to the corresponding author.CHANGE HISTORY 16 July 2024 : A Correction to this paper has been published: https://doi.org/10.1038/s41433-024-03161-7.BACKGROUND :
To estimate global and regional trends from 2000 to 2020 of the number of persons visually impaired by cataract and their proportion of the total number of vision-impaired individuals.
METHODS :
A systematic review and meta-analysis of published population studies and gray literature from 2000 to 2020 was carried out to estimate global and regional trends. We developed prevalence estimates based on modeled distance visual impairment and blindness due to cataract, producing location-, year-, age-, and sex-specific estimates of moderate to severe vision impairment (MSVI presenting visual acuity <6/18, ≥3/60) and blindness (presenting visual acuity <3/60). Estimates are age-standardized using the GBD standard population.
RESULTS :
In 2020, among overall (all ages) 43.3 million blind and 295 million with MSVI, 17.0 million (39.6%) people were blind and 83.5 million (28.3%) had MSVI due to cataract blind 60% female, MSVI 59% female. From 1990 to 2020, the count of persons blind (MSVI) due to cataract increased by 29.7%(93.1%) whereas the age-standardized global prevalence of cataract-related blindness improved by −27.5% and MSVI increased by 7.2%. The contribution of cataract to the age-standardized prevalence of blindness exceeded the global figure only in South Asia (62.9%) and Southeast Asia and Oceania (47.9%).
CONCLUSIONS :
The number of people blind and with MSVI due to cataract has risen over the past 30 years, despite a decrease in the age-standardized prevalence of cataract. This indicates that cataract treatment programs have been beneficial, but population growth and aging have outpaced their impact. Growing numbers of cataract blind indicate that more, better-directed, resources are needed to increase global capacity for cataract surgery.Brien Holden Vision Institute, Fondation Thea, Fred Hollows Foundation, Bill & Melinda Gates Foundation, Lions Clubs International Foundation (LCIF), Sightsavers International, and University of Heidelberg. Open Access funding enabled and organized by CAUL and its Member Institutions.https://www.nature.com/eyehj2024School of Health Systems and Public Health (SHSPH)SDG-03:Good heatlh and well-bein