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Salmonella enterica serovars Typhi and Paratyphi A cause systemic infections in humans which are referred to as enteric fever. Multidrug-resistant (MDR) serovar Typhi isolates emerged in the 1980s, and in recent years MDR serovar Paratyphi A infections have become established as a significant problem across Asia. MDR in serovar Typhi is almost invariably associated with IncHI1 plasmids, but the genetic basis of MDR in serovar Paratyphi A has remained predominantly undefined. The DNA sequence of an IncHI1 plasmid, pAKU_1, encoding MDR in a serovar Paratyphi A strain has been determined. Significantly, this plasmid shares a common IncHI1-associated DNA backbone with the serovar Typhi plasmid pHCM1 and an S. enterica serovar Typhimurium plasmid pR27. Plasmids pAKU_1 and pHCM1 share 14 antibiotic resistance genes encoded within similar mobile elements, which appear to form a 24-kb composite transposon that has transferred as a single unit into different positions into their IncHI1 backbones. Thus, these plasmids have acquired similar antibiotic resistance genes independently via the horizontal transfer of mobile DNA elements. Furthermore, two IncHI1 plasmids from a Vietnamese isolate of serovar Typhi were found to contain features of the backbone sequence of pAKU_1 rather than pHCM1, with the composite transposon inserted in the same location as in the pAKU_1 sequence. Our data show that these serovar Typhi and Paratyphi A IncHI1 plasmids share highly conserved core DNA and have acquired similar mobile elements encoding antibiotic resistance genes in past decades.  相似文献   
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Parthenium poses serious threat to modern crop production system and necessitate evaluating control practices for its effective management. Efficacy of different weed control practices for controlling parthenium was explored in conventional and deep tillage systems in the field conditions. Hand hoeing (20 and 35 days after emergence), S-Metolachlor (pre-emergence herbicide), sorghum straw mulch @ 5 tons ha-1 and combination of hand hoeing and sorghum straw mulch (hand hoeing at 20 and straw mulch at 35 days after emergence) were used as weed control practice. Weedy check where no weed control measure was applied was also included in this experiment for comparison. Results concluded that the all weed management treatments significantly reduced parthenium density, its fresh and dry biomass during both the years of study as compared to weedy check. Maximum sunflower achene yield was recorded in hand hoeing (20 and 35 days after emergence) in combination with deep tillage. So, mold bold plough used for the purpose of deep tillage should be encouraged for better control of parthenium and higher achene yield of sunflower crop (3293.3 kg ha-1 in 2017 and 3221.3 kg ha-1 in 2018). Moreover, is also inferred that total dose of herbicide might be reduced by using hoeing and mulching in an integrated way.  相似文献   
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Bioprocess and Biosystems Engineering - Polyhydroxyalkanoates (PHAs) are biological plastics that are sustainable alternative to synthetic ones. Numerous microorganisms have been identified as PHAs...  相似文献   
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BackgroundIndia launched the National Rural Health Mission (NRHM) in 2005 to strengthen its primary healthcare system in high-focus and northeast-focus states. One of the NRHM objectives was to reduce child undernutrition in India.Methods and findingsWe used data from 1992, 1998, 2005, and 2015 National Family Health Survey (NFHS) of India to evaluate trends in child undernutrition prevalence before and after NRHM and across different categories of focus states. Stunting, Wasting, and Comprehensive Index of Anthropometric Failure (CIAF) were assessed using the World Health Organization (WHO) growth curves to assess chronic, acute, and overall undernutrition. The study included 187,452 children aged 3 years or under. Survey-weighted and confounder-adjusted average annualized reduction rates (AARRs) and predicted probability ratios were used to assess trends and socioeconomic disparities for child undernutrition, respectively. Nationwide, the prevalence of all types of undernutrition decreased from 1992 to 2015. However, the trends varied before and after NRHM implementation and differentially by focus states. After NRHM, acute undernutrition declined more rapidly among high-focus states (AARR 1.0%) but increased in normal-focus states (AARR −1.9% per year; p-value for the difference <0.001). In contrast, the prevalence of chronic undernutrition declined more rapidly (AARR 1.6%) in the normal-focus states in comparison to high-focus states (0.3%; p-value for the difference = 0.01). Income and caste-based disparities in acute undernutrition decreased but did not disappear after the implementation of the NRHM. However, similar disparities in prevalence of chronic undernutrition appear to be exacerbated after the implementation of the NRHM. Major limitations of this study include the observational and cross-sectional design, which preclude our ability to draw causal inferences.ConclusionsOur results suggests that NRHM implementation might be associated with improvement in wasting (acute) rather than stunting (chronic) forms of undernutrition. Strategies to combat undernutrition equitably, especially in high-focus states, are needed.

Apurv Soni and co-workers study child undernutrition in India during implementation of the National Rural Health Mission.  相似文献   
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An acetone extract of the stem of Gnetum latifolium Blume afforded the stilbene trimer (latifolol) together with five known stilbenoids (gnetin E, gnetin D, gnetin C, (-)epsilon -viniferin and resveratrol). Their structures were elucidated on the basis of spectral evidence, in particular by using 2D NMR methods.  相似文献   
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Seven 9,10-seco-9,19-cyclolanostane arabinosides, named podocarpasides A-G (1-7), were isolated from the roots of Actaea podocarpa DC., a species closely related to black cohosh (a well known dietary supplement). Their structures were determined with the help of spectroscopic data including extensive 2D NMR spectroscopy. The isolates were found inactive, when tested for cytotoxic, estrogenic, and antioxidant activities in cell based assays. They were also tested for anticomplement activity against the classical pathway of complement system and only podocarpaside C (3) inhibited modest complement activity with an IC50 value of 200 microM.  相似文献   
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Mutation in the PROM1 gene previously has been identified in one family with retinal degeneration for which neither ERG recordings nor detailed information about visual impairment is available. A large family with multiple individuals affected by retinal degeneration was ascertained in the Punjab province of Pakistan. The visual acuity of all affected patients in the family was severely compromised beginning in early childhood. The retinal disease in this family is a severe form of retinitis pigmentosa (RP) accompanied by macular degeneration. Fundus changes advanced with age. Choriocapillaris atrophy and posterior RPE atrophy were obvious allowing visualization of the large choroidal vessels in patients over 40 years of age. Rod and cone responses on ERG recordings were extinguished in patient’s teens. A genome-wide scan mapped the disease to a 34.7 cM region of chromosome 4p14–p16 between D4S1599 and D4S405. A maximum lod score of 3.96 with D4S403 and D4S391 is seen at θ = 0. Sequence analysis of PROM1 located in the linkage interval identified a c.1726C>T homozygous transition in exon 15: resulting in p.Gln576X in the translated protein. This mutation is found in a homozygous state in all six affected individuals and was heterozygous in five of the six unaffected family members examined. The mutation was not detected in 192 chromosomes of unrelated control individuals of the same ethnicity and from the same region. This delineates the phenotypic characteristics of retinopathy caused by mutations in PROM1. Qingjiong Zhang, Fareeha Zulfiqar, Xueshan Xiao, Sheikh Riazuddin and J. Fielding Hejtmancik contributed equally.  相似文献   
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