| 1. |
- Chatterjee, D., et al.
(författare)
-
Groundwater arsenic in the fluvial Bengal plains : geochemistry and mitigation
- 2013
-
Ingår i: PROCEEDINGS OF THE FOURTEENTH INTERNATIONAL SYMPOSIUM ON WATER-ROCK INTERACTION, WRI 14. - : ELSEVIER SCIENCE BV. ; , s. 143-146
-
Konferensbidrag (refereegranskat)abstract
- The water quality and chemistry of the groundwater of the fluvial Bengal plains have been investigated. It has been found that shallow aquifers (< 50 m bgl) are contaminated in a few pockets, surrounded by areas with low arsenic (As)/As-free groundwater, while the deeper aquifer (> 100 m bgl) is generally free from As (< 10 mu g/L). It also reveals that multiple As mobilization processes are occurring simultaneously, rather than any single geochemical process. An attempt has been made to demonstrate the degree of As heterogeneity with groundwater quality, and this has been followed by a few local conditions. The study further suggests that the As distribution (spatio-vertical) helps to identify safe shallow aquifers, and several signatures (colour of the sediments /land use pattern/ geomorphological features /local recharge events) are apparent that can be useful for formulating long-term mitigation options.
|
|
| 2. |
- Amin, Md. Nurul, et al.
(författare)
-
Evaluation of Late Blight (Phytophthora infestans L.) Tolerant Potato Varieties for Northern Bangladesh
- 2023
-
Ingår i: Gesunde Pflanzen. - : Springer. - 0367-4223 .- 1439-0345. ; 75:6, s. 2269-2279
-
Tidskriftsartikel (refereegranskat)abstract
- The precarious potato disease known as late blight (LB), which is brought on by Phytophthora infestans, quickly decimates crops and economically detriment growers. The pathogen prefers relatively cold temperatures and that usually prevails in northern Bangladesh. To decrease the number of fungicide sprays with the changing climate, it is necessary to identify potato varieties that are most resistant to late blight. This study aims to assess the growth and production performance of late blight-tolerant potato varieties in the northern part of Bangladesh. The field study was conducted in the crop-growing years of 2017-18 and 2018-19. In this study, three exotic potato varieties [(BARI Alu-90 (Alouette), BARI Alu-91 (Carolus), and BARI Alu-77 (Sarpomira)] and two check varieties [BARI Alu-8 (Cardinal) and BARI Alu-25 (Asterix)] were used. Compared with the two cultivated varieties BARI Alu-8 (Cardinal) and BARI Alu-25 (Asterix), the BARI Alu-90 (Alouette) with the highest level of late blight resistance based on AUDPC scoring (late blight estimated mean value of 5.9). The result showed that the majority of the evaluated variety BARI Alu-90 (Alouette) and BARI Alu-91 (Carolus) were highly resistant and BARI Alu-77 (Sarpomira) is moderately resistant. In contrast, the check varieties were susceptible to late blight. The yield and shelf life (or storage) quality of BARI Alu-90 (Alouette) was also good compared with the other varieties. Considering the yield, yield contributing characters, shelf-life data and disease resistance level BARI Alu-90 (Alouette) can be grown in northern Bangladesh without chemical protection.
|
|
| 3. |
- Biswas, Ashis, et al.
(författare)
-
Groundwater chemistry and redox processes : Depth dependent arsenic release mechanism
- 2011
-
Ingår i: APPLIED GEOCHEMISTRY. - : Elsevier BV. ; , s. 516-525
-
Konferensbidrag (refereegranskat)abstract
- Patchy occurrences of elevated As are often encountered in groundwater from the shallow aquifers (<50 m) of the Bengal Delta Plain (BDP). A clear understanding of various biogeochemical processes, responsible for As mobilization, is very important to explain this patchy occurrence and thus to mitigate the problem. The present study deals with the periodical monitoring of groundwater quality of five nested piezometeric wells between December 2008 and July 2009 to investigate the temporal changes in groundwater chemistry vis-a-vis the prevalent redox processes in the aquifer. Geochemical modeling has been carried out to identify key phases present in groundwater. A correlation study among different aqueous redox parameters has also been performed to evaluate prevailing redox processes in the aquifer. The long term monitoring of hydrochemical parameters in the multilevel wells together with hydrogeochemical equilibrium modeling has shown more subtle differences in the geochemical environment of the aquifer, which control the occurrence of high dissolved As in BDP groundwater. The groundwater is generally of Ca-HCO3 type. The dissolved As concentration in groundwater exceeded both WHO and National drinking water standard (Bureau of Indian Standards; BIS, 10 mu g L-1) throughout the sampling period. The speciation of As and Fe indicate persistent reducing conditions within the aquifer [As(III): 87-97% of As-T and Fe(II): 76-96% of Fe-T]. The concentration of major aqueous solutes is relatively high in the shallow aquifer (wells A and B) and gradually decreases with increasing depth in most cases. The calculation of SI indicates that groundwater in the shallow aquifer is also relatively more saturated with carbonate minerals. This suggests that carbonate mineral dissolution is possibly influencing the groundwater chemistry and thereby controlling the mobilization of As in the monitored shallow aquifer. Hydrogeochemical investigation further suggests that Fe and/or Mn oxyhydroxide reduction is the principal process of As release in groundwater from deeper screened piezometric wells. The positive correlations of U and V with As. Fe and Mn indicate redox processes responsible for mobilization of As in the deeper screened piezometric wells are possibly microbially mediated. Thus, the study advocates that mobilization of As is depth dependent and concentrations of As in groundwater depends on single/combined release mechanisms.
|
|
| 4. |
- Chatterjee, Debashis, et al.
(författare)
-
Assessment of arsenic exposure from groundwater and rice in Bengal Delta Region, West Bengal, India
- 2010
-
Ingår i: Water Research. - : Elsevier BV. - 0043-1354 .- 1879-2448. ; 44:19, s. 5803-5812
-
Tidskriftsartikel (refereegranskat)abstract
- Arsenic (As) induced identifiable health outcomes are now spreading across Indian subcontinent with continuous discovery of high As concentrations in groundwater. This study deals with groundwater hydrochemistry vis-a-vis As exposure assessment among rural population in Chakdaha block, West Bengal, India. The water quality survey reveals that 96% of the tubewells exceed WHO guideline value (10 mu g/L of As). The groundwaters are generally anoxic (-283 to -22 mV) with circum-neutral pH (6.3 to 7.8). The hydrochemistry is dominated by HCO3- (208 to 440 mg/L), Ca2+ (79 to 178 mg/L) and Mg2+ (17 to 45 mg/L) ions along with high concentrations of As-T (As total, below detection limit to 0.29 mg/L), Fe-T (Fe total, 1.2 to 16 mg/L), and Fe(II) (0.74 to 16 mg/L). The result demonstrates that Fe(II)-Fe(III) cycling is the dominant process for the release of As from aquifer sediments to groundwater (and vice versa), which is mainly controlled by the local biogeochemical conditions. The exposure scenario reveals that the consumption of groundwater and rice are the major pathways of As accumulation in human body, which is explained by the dietary habit of the surveyed population. Finally, regular awareness campaign is essential as part of the management and prevention of health outcomes. (c) 2010 Elsevier Ltd. All rights reserved.
|
|
| 5. |
- Chatterjee, Pritam, et al.
(författare)
-
Second-order topological superconductor via noncollinear magnetic texture
- 2024
-
Ingår i: Physical Review B. - : American Physical Society. - 2469-9950 .- 2469-9969. ; 109:4
-
Tidskriftsartikel (refereegranskat)abstract
- We put forth a theoretical framework for engineering a two-dimensional (2D) second-order topological superconductor (SOTSC) by utilizing a heterostructure: incorporating noncollinear magnetic textures between an s-wave superconductor and a 2D quantum spin Hall insulator. It stabilizes the higher order topological superconducting phase, resulting in Majorana corner modes (MCMs) at four corners of a 2D domain. The calculated nonzero quadrupole moment characterizes the bulk topology. Subsequently, through a unitary transformation, an effective low-energy Hamiltonian reveals the effects of magnetic textures, resulting in an effective in-plane Zeeman field and spin-orbit coupling. This approach provides a qualitative depiction of the topological phase, substantiated by numerical validation within an exact real-space model. Analytically calculated effective pairings in the bulk illuminate the microscopic behavior of the SOTSC. The comprehension of MCM emergence is supported by a low-energy edge theory, which is attributed to the interplay between effective pairings of (px+py)-type and (px+ipy)-type. Our extensive study paves the way for practically attaining the SOTSC phase by integrating noncollinear magnetic textures.
|
|
| 6. |
- Dai, Qile, et al.
(författare)
-
OTTERS: a powerful TWAS framework leveraging summary-level reference data
- 2023
-
Ingår i: Nature Communications. - : Springer Nature. - 2041-1723. ; 14:1
-
Tidskriftsartikel (refereegranskat)abstract
- Most existing TWAS tools require individual-level eQTL reference data and thus are not applicable to summary-level reference eQTL datasets. The development of TWAS methods that can harness summary-level reference data is valuable to enable TWAS in broader settings and enhance power due to increased reference sample size. Thus, we develop a TWAS framework called OTTERS (Omnibus Transcriptome Test using Expression Reference Summary data) that adapts multiple polygenic risk score (PRS) methods to estimate eQTL weights from summary-level eQTL reference data and conducts an omnibus TWAS. We show that OTTERS is a practical and powerful TWAS tool by both simulations and application studies.
|
|
| 7. |
- Gill, Dipender, et al.
(författare)
-
ACE inhibition and cardiometabolic risk factors, lung ACE2 and TMPRSS2 gene expression, and plasma ACE2 levels : a Mendelian randomization study
- 2020
-
Ingår i: Royal Society Open Science. - : ROYAL SOC. - 2054-5703. ; 7:11
-
Tidskriftsartikel (refereegranskat)abstract
- Angiotensin-converting enzyme 2 (ACE2) and serine protease TMPRSS2 have been implicated in cell entry for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for coronavirus disease 2019 (COVID-19). The expression of ACE2 and TMPRSS2 in the lung epithelium might have implications for the risk of SARS-CoV-2 infection and severity of COVID-19. We use human genetic variants that proxy angiotensin-converting enzyme (ACE) inhibitor drug effects and cardiovascular risk factors to investigate whether these exposures affect lung ACE2 and TMPRSS2 gene expression and circulating ACE2 levels. We observed no consistent evidence of an association of genetically predicted serum ACE levels with any of our outcomes. There was weak evidence for an association of genetically predicted serum ACE levels with ACE2 gene expression in the Lung eQTL Consortium (p = 0.014), but this finding did not replicate. There was evidence of a positive association of genetic liability to type 2 diabetes mellitus with lung ACE2 gene expression in the Gene-Tissue Expression (GTEx) study (p = 4 x 10(-4)) and with circulating plasma ACE2 levels in the INTERVAL study (p = 0.03), but not with lung ACE2 expression in the Lung eQTL Consortium study (p = 0.68). There were no associations of genetically proxied liability to the other cardiometabolic traits with any outcome. This study does not provide consistent evidence to support an effect of serum ACE levels (as a proxy for ACE inhibitors) or cardiometabolic risk factors on lung ACE2 and TMPRSS2 expression or plasma ACE2 levels.
|
|
