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β-glucosidases (BGs) are key enzymes in cellulose hydrolysis, being the rate-limiting enzyme that is regulated by feedback inhibition from its own product—glucose. Due to which low hydrolysis yields are observed thus affecting overall ethanol yield per ton biomass. In this study, hydrolysis yields influence as a function of BG deficiency, supplementation, and its synergy in cellulase cocktails were investigated. Results show that commercial cellulase preparations were low in BG and produce hydrolysis yields below 60 % in 12 h. On blending commercial preparations with BGs (from fungal and bacterial sources), the degree of synergism was observed greater than 1, indicating that the components depicted synergistic behaviour in the mixture. A triple blend cellulase cocktail comprising commercial preparation, and two different BG preparations were optimized using the mixture design approach based on the synergism demonstrated. According to the findings, the in-house optimized cocktail (C-Mix) was able to hydrolyze six different two-stage treated LBM feedstocks and release more than 900 mg/g of glucose. The stability of the optimized cocktail was also enhanced two-fold due to strong synergistic interactions. Thus, a simple blending of BGs in the commercial preparations can be a sustainable approach for developing effective cocktails and intensifying cellulose hydrolysis. [Display omitted] • Cellulase cocktail was optimized for two-stage treated lignocellulosic biomass. • The stability and glucose productivity were improved by the optimized cocktail. • Supplementation of BG with cellulase preparations was correlated to synergy. • Ratios of supplementation were correlated in enhancing the stability of the cocktail. [ABSTRACT FROM AUTHOR]

The ambient dose H* is now defined as the product of the particle fluence at a point, , and the conversion coefficient, H*, relating particle fluence to the maximum value of effective dose, Emax, for various irradiation conditions. In view of the fact that protection quantities were not measurable in the field, it was necessary to define operational quantities which could be related by measurement to the radiation field. ICRP/ICRU have released a joint report[[1]] that changes the concept of the operational quantities, for area and individual monitoring in a major way. The operational quantities are redefined as the products of radiometric (or dosimetric) quantities and conversion coefficients. [Extracted from the article]

In this study, Antimony (Sb) doped tin oxide (SnO 2) thin films (ATO) were synthesized using the RF (radio frequency) sputtering technique with varying antimony concentrations (0, 3, 5, 7 wt%) and substrate temperatures of room temperature, 150 ℃, and 300 ℃. It was discovered that these thin films were tetragonal crystal structures with good crystallinity and grew preferentially along the (101) planes at the substrate temperature of 300 ℃. It was found that the 5 wt% doped film prepared at 300 ℃ substrate temperature exhibited superior gas-sensing properties under all tested conditions, and the 7 wt% doped sample showed properties that deviated from the trend observed up to 5 wt%. It was observed that the morphology of the film has a spongy spherical granular structure with a mesoporous surface. The presence of Sn, Sb5+/Sb3+, and oxygen was confirmed by XPS spectra analysis in the thin films. The n-type electrical conductivity was attained by combining an oxygen vacancy and antimony ions in the tin oxide lattice interstitial. Consequently, the inclusion of antimony increased conductivity up to 5 wt% was noticed. Doping makes remarkable changes in surface roughness (14–163.48 nm), which is attributed to the surface wettability. The film turns nearly hydrophilic when the doping concentration increases (59°). According to studies into a potential gas-sensing mechanism, the addition of Sb dopants, mesoporous structures, and high specific surface area was thought to be the reason for the improved gas-sensing response. Without a doubt, the current work may offer the best method to enhance H 2 gas response in particularly environmentally sensitive applications. [Display omitted] • ATO thin film has been produced using RF sputtering with varying doping concentrations and deposition temperatures. • Low concentration H 2 gas with 0.1 ppm level detection was carried out by using MOS-based thin films (ATO thin films). • 5 wt.% ATO films at 300 ℃ show the highest surface area and carrier concentration, driving for high gas sensitivity. • Developed ATO film is showing better repeatability and long-term stability. [ABSTRACT FROM AUTHOR]

Objectiv: To quantify ADRs in patients on cardiovascular drugs and to assess their severity. Materials and Methods: Based on inclusion and exclusion criteria, 265 inpatients on cardiovascular drugs from a tertiary care center were included in this prospective study. All patients were assessed for occurrence of ADR and followed up till the recovery of the ADR. Causality assessment of ADR was done, severity of ADR was graded, and preventability of ADR was assessed. Results: In the present study, descriptive statistics were used to analyze the data. Out of 265 patients screened, 137 (51.69%) had 245 ADRs. About 175 (71%) ADRs were due to antihypertensives, 175 (71%). On causality assessment of these ADRs, 230 (94%) were found to be possible and 15 (6%) probable. Two hundred and nine (85%) ADRs were mild, 34 (14%) were moderate, and 2 (1%) were severe. The most common ADR encountered in the study was giddiness due to various classes of antihypertensives in 26% about patients. Conclusions: Among the cardiovascular system drugs, antihypertensives were the most common group of drugs to cause giddiness as ADR. Majority of the ADRs had a score of "possible" because of concomitant medications. [ABSTRACT FROM AUTHOR]

Cellulases required for the conversion of biomass to sugars contribute to a significant part of the final bioethanol cost in the overall lignocellulosic biorefinery. It has been proven that recycling cellulases for saccharification is a viable method to lower the cost of the enzymatic hydrolysis process. Any method for recycling enzymes must begin with a stable cellulase cocktail that can withstand operational recycling conditions. The majority of commercial cellulase preparations contain a small quantity of β-glucosidases (BG), which lowers overall recyclability and causes low hydrolysis yields. This study examines the use of synergistic β-glucosidases (Atu BG3II and Pfu BG1 from Aspergillus tubingensis and Pyrococcus furiosus , respectively) to enhance the recyclability of cellulases during the hydrolysis process. It was able to recycle a significant amount of cellulases by recycling the insoluble solid fraction and liquid fraction following enzymatic hydrolysis of two-step treated wheat straw (ts-WS). In addition, the in-house cellulase cocktail (C-Mix) retained β-glucosidase activity and demonstrated glucose productivity of 18.9 g/L/h at 5% loading and enzyme efficiency (0.41 g of glucose per mg of protein) as Atu BG3II and Pfu BG1 did not adsorb significantly to the biomass. This resulted in a 3.5-fold improvement in the recyclability and a 33% increase in the hydrolysis yield during the study. Therefore, all these results signify better cellulase recovery using two-step treated lignocellulose and stable cellulase cocktails, demonstrating great potential for enzymatic recycling. [Display omitted] • Cellulase recyclability is affected by synergistic β-glucosidase supplementation. • Enzyme adsorbed solid residue can be recycled back enabling maximum enzyme recovery. • Atu BG3 and Pfu BG1 supplementation in cellulase AC led higher hydrolysis yield. • Two-step treatment lead to reduced biomass recalcitrance favouring recyclability. [ABSTRACT FROM AUTHOR]

In view of an underestimation of personal dose equivalent due to 60Co radiation when system is calibrated to 137Cs, the effect of the atomic number of the filters used in the badge on the photon beams of 660 keV and 1250 keV was investigated. The low Z-high Z interface created between filters and discs was found to lead to discontinuity in dose at the surface of the disc. This effect was consistently observable due to the 0.8 mm thickness of the disc. It was concluded that under-estimation of dose due to 60Co radiation could be avoided by either reducing the thickness of the dosimeter disc or by a slight modification in the design of the filters. [ABSTRACT FROM AUTHOR]

Structural modifications of the leaving group of S-glycosyl O -methyl phenylcarbamothioates (SNea) involving change of substituents that express different electronic effects led to a better understanding of how the reactivity of these glycosyl donors can be modified by changing the structure of their leaving groups. Mechanistic studies involving the isolation of departed aglycones were indicative of the direct activation of both p -methoxy-SNea and p -nitro-SNea leaving groups via the anomeric sulfur rather than the remote nitrogen atom. The presence of an electron donating substituent ( p -methoxy) has a strong effect on the nucleophilicity of the sulfur atom that becomes more susceptible toward the attack of thiophilic reagents, in particular. This key observation allowed to differentiate the reactivity levels of p -methoxy-SNea versus p -nitro-SNea and even unmodified SNea leaving groups. The reactivity difference observed in the series of SNea leaving groups is sufficient to be exploited in expeditious oligosaccharide synthesis via selective activation strategies. [ABSTRACT FROM AUTHOR]

The present study was made to quantify water stress in mahogany (Swietenia macrophylla King) seedlings using crop water stress index (CWSI). Seedlings were provided with four different levels of irrigation as treatments - irrigation at irrigation water (IW)/evapotranspiration (ET) = 1, 0.6 and 0.3 at weekly intervals and a control with no irrigation (IW/ET = 0). Canopy-air temperature difference (CATD) was recorded using an infrared thermometer. The non-water-stressed baseline (NWSB) was derived from CATD and vapour pressure deficit (VPD) in the well-watered treatment (irrigation at 1.0 IW/ET). The lower baseline equation for CATD was -0.25VPD - 2.9 and the upper baseline equation was -0.01VPD + 6.1. CWSI responded to irrigation events along the whole season and clearly detected mild water stress, suggesting extreme sensitivity to variations in plant water status. The present study reveals the potential of CWSI for early, non-destructive and less time-consuming estimation of water stress. [ABSTRACT FROM AUTHOR]

It is reported that S-glycosyl O-methyl phenylcarbamothioates (SNea carbamothioates) have a fully orthogonal character in comparison to S-benzoxazolyl (SBox) glycosides. This complete orthogonality was revealed by performing competitive glycosylation experiments in the presence of various promoters. The results obtained indicate that SNea carbamothioates have a very similar reactivity profile to that of glycosyl thiocyanates, yet are significantly more stable and tolerate selected protecting group manipulations. These features make the SNea carbamothioates new promising building blocks for further utilization in oligosaccharide synthesis. [ABSTRACT FROM AUTHOR]

A new surface-tethered iterative carbohydrate synthesis (STICS) technology is presented in which a surface functionalized ‘stick’ made of chemically stable high surface area porous gold allows one to perform cost efficient and simple synthesis of oligosaccharide chains; at the end of the synthesis, the oligosaccharide can be cleaved off and the stick reused for subsequent syntheses. [ABSTRACT FROM AUTHOR]

Review: 294 refs. [ABSTRACT FROM AUTHOR]

Studies on the response of 0.4 mm and 0.8 mm thick Teflon embedded CaSO4:Dy discs are carried out using different beta sources having energy ranging from 0.224 to 3.54 MeV. Angular dependence of the response for 0.4 and 0.8 mm thick thermoluminescence (TL) discs was also studied for 85Kr and 90Sr/90Y beta sources. The ratio of the response of the open disc to that under 1.5 mm thick Perspex filter (DOpen/DPerspex) was estimated for 0.4 and 0.8 mm thick TL discs in the energy range from 0.689 to 3.54 MeV. The evaluation of (DOpen/DPerspex) ratio is necessary as same is used to estimate the energy of beta particles and to apply appropriate correction factor while evaluating beta dose. In addition to above, the optical density and transmission characteristics for 0.4 and 0.8 mm thick Teflon and CaSO4:Dy Teflon embedded discs are also reported. [ABSTRACT FROM AUTHOR]

Background: We aimed to understand the association of gastrointestinal (GI) symptoms at initial presentation with clinical outcomes during COVID-19 hospitalization. Methods: This retrospective, multicenter cohort study included consecutive hospitalized COVID-19 patients from a single, large health system. The presence of GI symptoms was assessed at initial presentation and included one or more of the following: nausea, vomiting, diarrhea and abdominal pain. Patients were divided into three cohorts: Only GI symptoms, GI and non-GI symptoms and only non-GI symptoms. The primary outcome was association of GI symptoms with mortality. Secondary outcomes included prevalence of GI symptoms and survival analysis. Results: A total of 1672 COVID-19 patients were hospitalized (mean age: 63 ± 15.8 years, females: 50.4%) in our system during the study period. 40.7% patients had at least one GI symptom (diarrhea in 28.3%, nausea/vomiting in 23%, and abdominal pain in 8.8% patients), and 2.6% patients had only GI symptoms at initial presentation. Patients presenting with GI symptoms (with or without non-GI symptoms) had a lower mortality rate compared to patients presenting with only non-GI symptoms (20% vs. 26%; p < 0.05). The time from hospitalization to being discharged was less for patients presenting with only GI symptoms (7.4 days vs. > 9 days, p < 0.0014). After adjusting for other factors, the presence of GI symptoms was not associated with mortality (p > 0.05). Conclusion: Among a hospitalized COVID-19 positive Southern US population, 41% patients presented with either diarrhea, nausea, vomiting or abdominal pain initially. The presence of GI symptoms has no association with in-hospital all-cause mortality. [ABSTRACT FROM AUTHOR]

Obesity is a disorder of lipid metabolism and continues to be a global problem, ranking fifth for deaths worldwide. It also leads to diabetes, cardiovascular disorders, musculoskeletal disorders and some types of cancer. Obesity is regarded as the output of a long-term imbalance between energy intake and energy expenditure. Digestion and absorption of dietary lipids by pancreatic lipase, a major source of excess calorie intake, can be targeted for development of anti-obesity agents. Being the major factor of concern, food materials and edible plants are most widely studied for the anti-obesity activity, so that they can be incorporated in the routine diet. In this review, an attempt was made to present a current scenario of the bioactive compounds from plant and microbial origin that have been investigated for their pancreatic lipase inhibition. Compounds belonging to various classes of natural products such as alkaloids, carotenoids, glycosides, polyphenols, polysaccharides, saponins and terpenoids are well studied while lipophilic compounds from microbial sources are the most active against the pancreatic lipase. Few studies on the synthetic analogues, structurally similar to the triglycerides have been described in the review. Despite of tremendous research on the finding of potential pancreatic lipase inhibitor, very few compounds have entered the clinical studies and no new molecule after orlistat has been marketed. Along with HTS based screening, detailed structure-activity relationship studies on semi-synthetic and synthetic derivatives might also provide a direction for the development of potential lead(s) or pharmacophore for pancreatic lipase inhibition in order to treat and/or prevent obesity and related disorders. [ABSTRACT FROM AUTHOR]