31 research outputs found
Genetic variation in responses to salt stress in Tunisian populations of Medicago ciliaris
Soil salinity is one of the most serious environmental factors affecting crop productivity
around the world. We used a morpho-physiological approach to investigate the salt responses
of four Tunisian natural populations of Medicago ciliaris. Forty-six lines of M. ciliaris were grown
under a control treatment and 100 mM NaCl. We measured 11 quantitative traits of shoot and root
growth during harvest. An analysis of variance showed that the variations in salt response can be
explained by the effects of the population, line, treatment, and interactions between the population
and treatment and the line and treatment. Most of the measured traits showed significant differences
between the studied populations under the control treatment and salt stress
Variability in Responses to Phoma medicaginis Infection in a Tunisian Collection of Three Annual Medicago Species
Spring black stem and leaf spot, caused by Phoma medicaginis, is an issue in annual Medicago species. Therefore, in this study, we analyzed the response to P. medicaginis infection in a collection of 46 lines of three annual Medicago species (M. truncatula, M. ciliaris, and M. polymorpha) showing different geographic distribution in Tunisia. The reaction in the host to the disease is explained by the effects based on plant species, lines nested within species, treatment, the interaction of species × treatment, and the interaction of lines nested within species × treatment. Medicago ciliaris was the least affected for aerial growth under infection. Furthermore, the largest variation within species was found for M. truncatula under both conditions. Principal component analysis and hierarchical classification showed that M. ciliaris lines formed a separate group under control treatment and P. medicaginis infection and they are the most vigorous in growth. These results indicate that M. ciliaris is the least susceptible in response to P. medicaginis infection among the three Medicago species investigated here, which can be used as a good candidate in crop rotation to reduce disease pressure in the field and as a source of P. medicaginis resistance for the improvement of forage legumes
Graves' Disease Associated with Cerebrovascular Disease and Antiphospholipid Antibody Syndrome
Thyroid disorders are commonly associated with coagulopathy. Patients with hyperthyroidism
have increased risk for developing thromboembolic accidents, which are favoured by a simultaneous presence of antiphospholipid antibodies syndrome. in this paper, we describe the case of a patient with Graves' disease, who developed strokes with antiphospholipid antibodies syndrome
Harnessing the potential of endophytes: Sustainable solutions for enhancing forage crop resilience and soil fertility
Environmental changes pose significant challenges to sustainable agriculture, adversely affecting crop production and soil fertility. Factors such as drought, salinity, pathogens, and soil type exert their influence on the behavior of fodder crops by altering their morphological, biochemical, and molecular mechanisms, ultimately leading to reduced yields and productivity. Consequently, there is a pressing need to develop mitigation strategies aimed at enhancing the tolerance of forage crops to both biotic and abiotic stresses, addressing a critical challenge in sustaining their growth.
In recent times, the use of biofertilizers has emerged as an environmentally friendly alternative to chemical fertilizers, holding promise for sustainable horticultural, agricultural, and forestry production systems. Notably, endophytic microorganisms play a pivotal role in promoting plant growth through direct or indirect mechanisms. Additionally, endophytic bacteria actively regulate gene expression responsible for the production of antioxidant enzymes, various phytohormones, siderophores, and ROS scavenging enzymes, all of which contribute to supporting the growth of host plants even in extreme environments. Consequently, there is a growing focus on understanding and validating the mechanisms through which beneficial plant endophytes interact to combat both biotic and abiotic stresses.
This review emphasizes the potential of endophytes as biofertilizers, biocontrol agents, and contributors to the mitigation of abiotic and biotic stresses, all of which play crucial roles in maintaining the development of forage crops and soil fertility
Case Report Graves' Disease Associated with Cerebrovascular Disease and Antiphospholipid Antibody Syndrome
Thyroid disorders are commonly associated with coagulopathy. Patients with hyperthyroidism have increased risk for developing thromboembolic accidents, which are favoured by a simultaneous presence of antiphospholipid antibodies syndrome. in this paper, we describe the case of a patient with Graves' disease, who developed strokes with antiphospholipid antibodies syndrome
تصورات القطريين للدين: دراسة استكشافية
تسعى هذه الدراسة الميدانية الاستكشافية إلى معالجة مسألة التصورات الدينية لدى المجتمع القطري؛ من حيث دلالة مفهومها وموقعها، ومدى أهميتها لدى أعضاء المجتمع، من خلال مقاربة المصادر التي يستمد منها هذا المجتمع مختلف تصوراته حول الدين، باعتماد عدد من التساؤلات، يمكن إجمالها في الآتي: ما تصورات القطريين للدين؟ أي أبعاد الدين أكثر حضورًا في أذهان القطريين وممارساتهم؟ ما مصادر المجتمع القطري في تصوراته للدين؟
وتكمن أصالة هذه الدراسة في ربط التصورات الدينية لدى المجتمع القطري بممارسات أعضائه اليومية من جهة، والمصادر التي يستندون إليها في تعريف الدين نفسه من جهة ثانية، ما جعل هذه الدراسة متفردة في تغطية جانب بحثي مهم طال التغافل عنه، باعتماد منهج مختلط جمع بين الكيفي (النوعي) والكمي، بهدف خلق تكامل بين البيانات النوعية والكمية، مما من شأنه أن يقدِّم تحليلًا أكثر شمولًا وسلاسة في فهم تصورات القطريين للدين.
وخلصت الدراسة أولًا: إلى أن كلًا من العقيدة والعبادات يمثلان النواة المركزية في تشكيل تصور القطريين عن الدين، فيما تعتبر بقية العناصر المحيطة بهما أبعادًا مساعدة في تشكيل ذلك التصور، ولا تعبر عن جوهره بالضرورة. وثانيًا: إلى أن هناك انسجامًا بين التصورات الاعتقادية والعملية، تمثل في وعي القطريين بأن أهمية عاداتهم وتقاليدهم نابعة من ارتباطها بالدين، لا من مخالفتها له
Variability in Responses to Phoma medicaginis Infection in a Tunisian Collection of Three Annual Medicago Species
Spring black stem and leaf spot, caused by Phoma medicaginis, is an issue in annual Medicago species. Therefore, in this study, we analyzed the response to P. medicaginis infection in a collection of 46 lines of three annual Medicago species (M. truncatula, M. ciliaris, and M. polymorpha) showing different geographic distribution in Tunisia. The reaction in the host to the disease is explained by the effects based on plant species, lines nested within species, treatment, the interaction of species × treatment, and the interaction of lines nested within species × treatment. Medicago ciliaris was the least affected for aerial growth under infection. Furthermore, the largest variation within species was found for M. truncatula under both conditions. Principal component analysis and hierarchical classification showed that M. ciliaris lines formed a separate group under control treatment and P. medicaginis infection and they are the most vigorous in growth. These results indicate that M. ciliaris is the least susceptible in response to P. medicaginis infection among the three Medicago species investigated here, which can be used as a good candidate in crop rotation to reduce disease pressure in the field and as a source of P. medicaginis resistance for the improvement of forage legumes
Evaluation of the morpho-physiological, biochemical and molecular responses of contrasting Medicago truncatula lines under water deficit stress
This article belongs to the Special Issue Molecular Analysis of Medicago Spp.Medicago truncatula is a forage crop of choice for farmers, and it is a model species for molecular research. The growth and development and subsequent yields are limited by water availability mainly in arid and semi-arid regions. Our study aims to evaluate the morpho-physiological, biochemical and molecular responses to water deficit stress in four lines (TN6.18, JA17, TN1.11 and A10) of M. truncatula. The results showed that the treatment factor explained the majority of the variation for the measured traits. It appeared that the line A10 was the most sensitive and therefore adversely affected by water deficit stress, which reduced its growth and yield parameters, whereas the tolerant line TN6.18 exhibited the highest root biomass production, a significantly higher increase in its total protein and soluble sugar contents, and lower levels of lipid peroxidation with greater cell membrane integrity. The expression analysis of the DREB1B gene using RT-qPCR revealed a tissue-differential expression in the four lines under osmotic stress, with a higher induction rate in roots of TN6.18 and JA17 than in A10 roots, suggesting a key role for DREB1B in water deficit tolerance in M. truncatula.This study was supported by the Tunisian Ministry of Higher Education and Scientific Research (CBBC02 LR15) and the National Research Foundation of South Africa (GUN 95358) in the framework of the Tunisian-South African Joint Research Collaboration Program (2016–2017).Peer reviewe
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Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021
BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation
Morpho-phenological diversity among natural populations of Medicago polymorpha of different Tunisian ecological areas
Medicago polymorpha is a herbaceous legume that can be a useful pasture plant, in particular, in regions with a Mediterranean climate. The genetic variation in 120 lines of M. polymorpha sampled from five regions in Tunisia was characterized on the basis of 16 morpho-phenological characters. Results from analysis of variance (ANOVA) showed that differences among populations and lines existed for all traits, with population explaining the greatest variation for measured traits. The populations of Enfidha and Soliman were the earliest flowering, while those of El Kef, Bulla Regia and Mateur were the latest. El Kef and Mateur exhibited the highest aerial dry weight while the lowest value was found for Soliman. Moderate to lower levels of heritability (H²) were registered for investigated traits. There was no significant association between pairwise population differentiation (QST) and geographical distances. Studied lines were clustered into three groups with 59 for the first group, 34 for the second group, and 27 lines for the third group. The lines of the first two groups showed the largest length of stems while those of the second group had the highest number of leaves. The variation of quantitative traits among populations was influenced by the altitude, temperature and relative humidity. Overall, the high levels of within population variation and the lack of correlation between population differentiation and geographical distances suggest a potentially important rate of long-distance seed dispersal and confirm the role played by natural selection in the population structure of Tunisian populations of M. polymorpha.Keywords: Medicago polymorpha, populations, quantitative traits, population differentiation, environmental parameter