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Tajikistan's rangelands are mostly mountainous and consist of summer and winter pastures. Vegetation structure and composition in these diverse landscapes are generally influenced by environmental factors. The objective of this study was to assess the effects of aspect on vegetation characteristics of two mountainous pastures (summer and winter) over two seasons (autumn and spring) in Tajikistan. A three-way ANOVA was conducted using GLM procedures to test the main effects and interactions of these factors on vegetation attributes. The biomass production (kg DM ha−1) was significantly greater on the north-facing aspects for both summer and winter pastures in spring (483.4, 326.1) and autumn (57.2, 143.9), compared with south-facing aspects (57.2, 143.9 in spring and 18.5, 48.2 in autumn, respectively). Plant cover and plant density were also greater on north than south-facing slopes for summer and winter pastures in spring and autumn. Aspect significantly affected species diversity, botanic composition, and plant life forms of both pastures mainly for grasses and geophytes. There were greater vegetation responses on north than south-facing slopes, implying that aspect is important when designing mountain rangeland restoration. Given this complexity, land managers should thoroughly assess the conditions of the target site before defining restoration objectives and interventions. [ABSTRACT FROM AUTHOR]

ABSTRACT Tajikistan is an exceptionally vulnerable Central Asian country in the face of climate change due to its' high exposure and sensitivity to climate change combined with poor adaptation capacity. Therefore, comprehensive climate data are needed for efficient planning of mitigation and adaptation. Here, the key spatio-temporal features of Tajikistan's climate were analysed based on historical data from 52 stations with the longest time-series covering nearly 80 years. In addition, bias-corrected CMIP5 climate models were used to simulate future temperature and precipitation conditions across a range of time periods and greenhouse gas emission scenarios. The results show that the mean annual temperatures have risen in Tajikistan since the 1930s, average rate of change being approximately 0.1 °C decade−1. For precipitation, only a weak signal of change could be detected. The high-resolution (30 arc seconds) spatial analyses reveal the strong control of topography on Tajikistan's climate with such coupling leading mean annual air temperatures to vary from −13.7 °C (eastern mountain regions) to 17.3 °C (low-altitude plains). Similarly, the mean annual precipitation vary from less than 50 mm to over 1000 mm, spring being the wettest of the seasons. The future climate simulations suggest drastic increase in air temperatures; at the end of this century the temperature multi-model mean can be approximately 2 °C (Representative Concentration Pathways, RCP2.6) to 7 °C ( RCP8.5) higher compared to 1961-1990. Precipitation scenarios indicate increase in the eastern part of the country and decrease in the west. Finally, the applied spatial uncertainty analyses stress the need for the future development of the climate station network especially in high-elevation areas associated with complex topography. These results show the pronounced climatic variation in Tajikistan and the expected near- and long-term changes in air temperature and precipitation conditions, thus forming a sound basis for future planning of national mitigation and adaptation activities. [ABSTRACT FROM AUTHOR]

Abstract: Lake Karakul in the Pamirs (Tajikistan) is a deep brackish-water lake in a closed basin at almost 4000m above sea level. Water samples from the catchment area and Lake Karakul, and a 104-cm sediment core from its shallow eastern sub-basin, were investigated and provide a first lake record from the region spanning the last 4200cal yr BP. Multi-proxy analyses revealed the following: A relatively high meltwater inflow from glaciers, snow fields and frozen ground in the catchment as a result of relatively warm conditions was reconstructed for the period between 4200 and 3500cal yr BP. The shift to colder climatic conditions around 3500cal yr BP was probably abrupt; total organic carbon values displayed the most dramatic drop for the entire core within less than 40years. In contrast, the subsequent re-establishment of warmer conditions occurred gradually over several centuries. A higher meltwater supply to the lake and warmer conditions were recorded since ca. 1900cal yr BP with two slightly colder intervals between 1200 and 800cal yr BP and between 400 and 100cal yr BP. The abrupt shift to significantly colder and drier conditions around 3500cal yr BP in the eastern Pamirs is seen also in records from the Aral Sea and the Guliya ice core from the western Tibetan Plateau. However, more palaeoclimate studies in this highly continental part of Central Asia are needed to assess the spatial and temporal patterns of the Holocene climate in the region. [Copyright &y& Elsevier]

• Different patterns of soil leaf wax isotopes in eastern vs western Pamirs. • Western/central Pamirs: soil isotopes correlated with altitude and longitude. • Isotopic lapse rate vs altitude is lower than the global average. • Eastern Pamirs: multiple local effects lead to higher δ2H values. • Local control on soil isotopes important for interpretation of paleorecords. Understanding the control mechanisms that affect soil leaf wax hydrogen isotopes is crucial when interpreting these data in the context of paleoclimatic reconstructions. Within a pilot study we aimed to evaluate the regional controls on leaf wax δ2H in the Central Asian Pamir Mountains (Tajikistan), a region characterized by pronounced hydroclimatic gradients. Soil and tap water samples were collected along a ca. 1000 km west-east-gradient, spanning ca. 3100 m of altitude difference. The results give evidence of variable environmental control on soil leaf wax δ2H values in different sub-regions of the study area. In the western and central Pamirs, the plant lipids mirror the signal of a mostly riverine water source, with an isotopic signature mainly controlled by winter and spring precipitation. With ca. –1.3‰ change per 100 m altitude, soil leaf wax derived isotopic lapse rates in these samples are lower than in other Asian high-altitude settings and the global average, which confirms earlier findings from surface water analysis from the Pamirs. In contrast, soil samples from the shielded Karakul basin showed significantly higher δ2H values. Those most likely reflect the more positive isotope signal of a predominant summer precipitation in the arid eastern Pamirs, with potential additional enrichment due to local vapor recycling and soil- and leaf water evapotranspiration. While the predominant water source (precipitation vs river water) plays an important role on a local scale, the results further highlight the significance of regional climate effects on isotopic signals incorporated into leaf waxes. [ABSTRACT FROM AUTHOR]

Introduction: Tajikistan is scaling up molecular diagnostic and digital technologies to strengthen its fight against drug-resistant TB (DR-TB). The study aimed to document national scale-up GeneXpert/GxAlert and Open MRS from 2012-2019 and compare time taken from TB diagnosis to treatment and quality of data recording before and after the introduction of GxAlert. Methodology: This was a longitudinal study that included a comparison of historical cohorts. Continuous variables were compared using Wilcoxon Rank-Sum test and categorical variables using the chi square test. Results: GeneXpert was introduced in 2011 and scaled up to 46 instruments in 43 (51%) diagnostic laboratories by May 2019. GxAlert was introduced in August 2018 and connected with all GeneXpert instruments by February 2019. Open MRS was introduced in 2014 and implemented in all 108 treatment centers by mid-2018. Time from diagnosis to treatment pre-GxAlert (range 0-749, median 3, days) was significantly longer than with GxAlert (range 0-273, median 3, days) (p <0.001). The proportion of patients whose time from diagnosis to treatment was > 2 weeks was 16% (282/1740) pre-GxAlert and 11% (206/1902) with GxAlert (p < 0.001). Between 31%-34% of patients with DR-TB results in Open MRS did not have results available in GeneXpert/GxAlert systems. Where results were present in both systems, there were discrepancies in 8.2% of patients pre-GxAlert and 4.3% with GxAlert (p = 0.25). Conclusions: The scale-up of GeneXpert and digital technologies in Tajikistan was associated with a reduction in the proportion of patients with delays more than 2 weeks between diagnosis and treatment, but data quality recording improved only slightly. [ABSTRACT FROM AUTHOR]

Introduction: WHO End TB Strategy aims at achieving targets of 90% mortality reduction and 80% reduction in tuberculosis (TB) incidence by 2030, recommending better addressing TB and multidrug-resistant TB (MDR-TB) issues in key populations. Aim: The study aimed at having a snapshot of the epidemiological characteristics of the key populations among the new TB patients, registered in Tajikistan during 2017. Methodology: A cross-sectional study was conducted, using official TB registration data for all new TB case notification in Tajikistan in 2017. Results: The key population included 1,029 (19.8%) patients among all 5,182 new TB cases registered in 2017. The following selected subpopulations were identified: migrant workers – 728 (70.7%), diabetics – 162 (15.7%), HIV-positive – 138 (13.4%), heavy drinkers – 74 (7.2%), drug users – 50 (4.8%), ex-prisoners – 50 (4.8%), and homeless – 9 (0.9%). Among the key population, 307 (29.8%) patients were smearpositive, 145 (14.1%) were drug-sensitive and 116 (11.3%) had MonoDR/MDR-TB. Time to treatment initiation for smear-positive cases was ≤ 5 days for 303 (98.7%) patients. Being a key population was inversely related to gender (female) (OR = 0.25, 95% CI (0.21, 0.29)) and population type (rural) (OR = 0.64, 95% CI (0.55, 0.74)). Conclusion: Among the key population the identified overlaps of selected sub-populations would enable more efficiently reaching the certain groups. TB case detection at PHC levels needs to be targeted for improved rates for key population detection. In the key population sub-group of migrant workers’ special migration destinations are recommended to be explored and find out possible associations with drug resistance. [ABSTRACT FROM AUTHOR]

We report the findings of a prospective laboratory diagnostic accuracy study to evaluate the sensitivity, specificity, and predictive values of the Xpert MTB/RIF Ultra assay for Mycobacterium tuberculosis detection in fresh stool specimens from children under 15 years of age with confirmed tuberculosis (TB) disease from Dushanbe, Tajikistan. Six hundred eighty-eight (688) participants were enrolled from April 2019 to October 2021. We identified 16 participants (2.3%) with confirmed TB disease, defined as ≥1 TB sign/symptom plus microbiologic confirmation. With the Xpert MTB/RIF Ultra assay for stool, we found a sensitivity of 68.8% (95% CI, 46.0 to 91.5) and a specificity of 98.7% (95% CI, 97.8 to 99.5) in confirmed TB disease. Our results are comparable to other published studies; however, our cohort was larger and our confirmed TB disease rate lower than most. We also demonstrated that this assay was feasible to implement in a centralized hospital laboratory in a low-middle-income Central Asian country. However, we encountered obstacles such as lack of staffing, material ruptures, outdated government protocols, and decreased case presentation due to COVID-19. We found eight patients whose only positive test was an Xpert Ultra stool assay. None needed treatment during the study; however, three were treated later, suggesting such cases require close observation. Our report is the first from Central Asia and one of a few from a low-middle-income country. We believe our study demonstrates the generalizability of the Xpert MTB/RIF Ultra assay on fresh stool specimens from children and provides further evidence supporting WHO's approval of this diagnostic strategy. IMPORTANCE The importance of this report is that it provides further support for WHO's recent recommendation that fresh stool is an acceptable sample for GeneXpert TB testing in children, especially small children who often cannot produce an adequate sputum sample. Diagnosing TB in this age group is difficult, and many cases are missed, leading to unacceptable rates of TB illness and death. In our large cohort of children from Dushanbe, Tajikistan, the GeneXpert stool test was positive in 69% of proven cases of TB, and there were very few false-positive tests. We also showed that this diagnostic strategy was feasible to implement in a low-middle-income country with an inefficient health care delivery system. We hope that many more programs will adopt this form of diagnosing TB in children.

Background: Drug-resistant tuberculosis (TB) is a major public health concern threathing the success of TB control efforts, and this is particularily problematic in Central Asia. Here, we present the first analysis of the population structure of Mycobacterium tuberculosis complex isolates in the Central Asian republics Uzbekistan, Tajikistan, and Kyrgyzstan., Methods: The study set consisted of 607 isolates with 235 from Uzbekistan, 206 from Tajikistan, and 166 from Kyrgyzstan. 24-loci MIRU-VNTR (Mycobacterial Interspersed Repetitive Units - Variable Number of Tandem Repeats) typing and spoligotyping were combined for genotyping. In addition, phenotypic drug suceptibility was performed., Results: The population structure mainly comprises strains of the Beijing lineage (411/607). 349 of the 411 Beijing isolates formed clusters, compared to only 33 of the 196 isolates from other clades. Beijing 94-32 (n = 145) and 100-32 (n = 70) formed the largest clusters. Beijing isolates were more frequently multidrug-resistant, pre-extensively resistant (pre-XDR)- or XDR-TB than other genotypes., Conclusions: Beijing clusters 94-32 and 100-32 are the dominant MTB genotypes in Central Asia. The relative size of 100-32 compared to previous studies in Kazakhstan and its unequal geographic distribution support the hypothesis of its more recent emergence in Central Asia. The data also demonstrate that clonal spread of resistant TB strains, particularly of the Beijing lineage, is a root of the so far uncontroled MDR-TB epidemic in Central Asia.