The distribution of polar organic compounds typical of water contaminants (organic acids, alcohols, and aromatic compounds) associated with oil and gas production was measured between water and nine ...hydrophobic, room-temperature ionic liquids. The ionic liquids used in this study were 1-butyl-3-methylimidazolium bistrifluoromethanesulfonylimide, 1-hexyl-3-methylimidazolium bistrifluoromethanesulfonylimide, 1-octyl-3-methylimidazolium bistrifluoromethanesulfonylimide, 1-butyl-3-methylimidazolium hexafluorophosphate, trihexyltetradecylphosphonium bistrifluoromethanesulfonylimide, 1-butyl-1-methyl-pyrrolidinium bistrifluoromethanesulfonylimide, trihexyltetradecylphosphonium dodecylbenzenesulfonate, tributyltetradecylphosphonium dodecylbenzenesulfonate, and trihexyltetradecylphosphonium methanesulfonate. Sensitivity of the distribution coefficients to salinity, temperature, concentration, and pH was investigated. Partitioning into the ionic liquid varied considerably. Acetic acid did not significantly partition into the ionic liquid phase, except for the sulfonate-anion ionic liquids. The solubility of hexanoic acid in the ionic liquids was significant, where uptake of the protonated form from aqueous solution was observed for all of the ionic liquids studied. Other organics also showed high distribution coefficients, up to several hundred in the case of toluene and 1-nonanol. The distribution coefficients for toluene, 1-nonanol, cyclohexanone, and hexanoic acid were independent of ionic liquid-to-water ratio over the range from 0.02 to 1.0. The ionic liquids showed a large capacity for some organics, with solubilities measured above 100 g·L
−1
. Regeneration of the ionic liquids by rinsing and heating was studied, with mixed success. These experiments show that certain hydrophobic ionic liquids do have an affinity for organic contaminants in aqueous solution. However, practical application of the ionic liquids tested for detection or removal of selected water-soluble organics from the aqueous waste streams appears to be limited by the small, but significant, solubility of the ionic liquids in the aqueous phase and by difficulty in solvent regeneration. Further work aimed at determination of ionic liquids that dissolve target compounds and are nonhazardous and less soluble in aqueous solutions is recommended.
Only a minority of heavy drinking individuals develop alcoholic hepatitis (AH), for unclear reasons. We analyzed data from the Translational Research and Evolving Alcoholic Hepatitis Treatment ...cohort, consisting of subjects who drink heavily with normal results from liver tests (controls) and patients with AH. We examined risk factors for the development of AH including body mass index (BMI), drinking pattern and quantity, and sex.
We compared data from 145 patients with AH and 124 controls based on BMI when they joined the cohort; groups were matched for sex and race. Drinking patterns were assessed using the timeline followback method, the Alcohol Use Disorders Identification Test, and the National Institute of Alcohol Abuse and Alcoholism 6-question survey. We performed univariable and multivariable analyses to assess the effects of these factors and their interaction in increasing the risk for AH. We also explored the association between PNPLA3 variants and AH.
Cases with AH were older (47 vs 44 y; P = .03). For nearly all measures of quantity of alcohol consumed or frequency of binge drinking, controls drank more heavily than cases with AH. We did not find an association between BMI, sex, drinking patterns, and the presence of AH. Age and BMI were independent predictors for the severity of AH. When we analyzed cases and controls of European ancestry, the PNPLA3 single-nucleotide polymorphism rs738409 was associated with risk for AH (odds ratio, 1.89; P = .007).
Compared with heavy drinkers without liver disease, subjects with AH consumed lower levels of alcohol and had less binge drinking, suggesting an increased sensitivity to the toxic effects of alcohol. The risk for AH may be associated with the PNPLA3 rs738409 polymorphism.
Carboxylic ester hydrolases with the capacity to degrade polyesters are currently highly sought after for their potential use in the biological degradation of PET and other chemically synthesized ...polymers. Here, we describe MarCE, a carboxylesterase family protein identified via genome mining of a Maribacter sp. isolate from the marine sponge Stelligera stuposa. Based on phylogenetic analysis, MarCE and its closest relatives belong to marine‐associated genera from the Cytophaga–Flavobacterium–Bacteroides taxonomic group and appear evolutionarily distinct to any homologous carboxylesterases that have been studied to date in terms of structure or function. Molecular docking revealed putative binding of BHET, a short‐chain PET derivative, onto the predicted MarCE three‐dimensional structure. The synthetic ester‐degrading activity of MarCE was subsequently confirmed by MarCE‐mediated hydrolysis of 2 mM BHET substrate, indicated by the release of its breakdown products MHET and TPA, which were measured, respectively, as 1.28 and 0.12 mM following 2‐h incubation at 30°C. The findings of this study provide further insight into marine carboxylic ester hydrolases, which have the potential to display unique functional plasticity resulting from their adaptation to complex and fluctuating marine environmentsw.
Here, we present MarCE, a marine carboxylesterase from a sea sponge‐derived Maribacter sp. isolate J2146c, identified by enzyme activity screening and subsequent genome mining of the J2146c strain. Computational protein analyses indicated the potential novelty of MarCE, which was phylogenetically linked to carboxylesterase family proteins from bacteria that have been exclusively associated with marine environments, and found to share low homology with previously characterized reference carboxylesterases. The terephthalate ester BHET was predicted to bind at the MarCE active site, and the enzyme was cloned and expressed in Escherichia coli enabling the confirmation of its BHET‐hydrolysing activity. The identification of MarCE contributes to the diversification of the current pool of enzymes that could be employed as biocatalysts in the degradation and transformation of synthetic substrates, particularly those associated with plastic waste.
Based on a recent asymptotic analysis of a nonlinear model of a slack cable, a computationally efficient, linear model is developed for calculating the natural frequencies, mode shapes, and dynamic ...responses of stationary elevator traveling and compensation cables. The linear cable model consists of two vertical cable segments connected by a half-circular lower loop. The two vertical cable segments are modeled as a string with a variable tension due to the weight of the cable. The horizontal displacements of the cable segments consist of boundary-induced displacements and relative elastic displacements, where the boundary-induced displacements are interpolated from the displacements of the two lower ends of the cable segments, and the relative elastic displacements satisfy the corresponding homogeneous boundary conditions of the cable segments. The horizontal displacement of the lower loop is interpolated from those of the two lower ends of the two cable segments, and the bending stiffness of the lower loop is modeled by a spring with a constant stiffness, which can be calculated from the nonlinear model. Given a car position, the natural frequencies and mode shapes of an elevator traveling or compensation cable are calculated using the linear model and compared with those from the nonlinear model. The calculated natural frequencies are also compared with those from a full-scale experiment. In addition, the dynamic responses of a cable under a boundary excitation are calculated and compared with those from the nonlinear model. There is a good agreement between the predictions from the linear and nonlinear models and between the measured natural frequencies from the full-scale experiment and the corresponding calculated ones.
Abstract The aim of this study was to evaluate the accuracy of novel software-CMF-preCADS-for the prediction of soft tissue changes following repositioning surgery for zygomatic fractures. Twenty ...patients who had sustained an isolated zygomatic fracture accompanied by facial deformity and who were treated with repositioning surgery participated in this study. Cone beam computed tomography (CBCT) scans and three-dimensional (3D) stereophotographs were acquired preoperatively and postoperatively. The 3D skeletal model from the preoperative CBCT data was matched with the postoperative one, and the fractured zygomatic fragments were segmented and aligned to the postoperative position for prediction. Then, the predicted model was matched with the postoperative 3D stereophotograph for quantification of the simulation error. The mean absolute error in the zygomatic soft tissue region between the predicted model and the real one was 1.42 ± 1.56 mm for all cases. The accuracy of the prediction (mean absolute error ≤2 mm) was 87%. In the subjective assessment it was found that the majority of evaluators considered the predicted model and the postoperative model to be ‘very similar’. CMF-preCADS software can provide a realistic, accurate prediction of the facial soft tissue appearance after repositioning surgery for zygomatic fractures. The reliability of this software for other types of repositioning surgery for maxillofacial fractures should be validated in the future.
The strong and ductile single-phase body-centered-cubic (BCC) HfNbTaTiZr refractory high-entropy alloy (RHEA) is a potential structural material for high-temperature applications. However, the BCC ...phase stability in the intermediate temperature range (500–900 °C) needs to be better understood to make this alloy applicable to industry. In the present work, the phase decomposition of the HfNbTaTiZr RHEA is examined at different temperatures (500–1000 °C). Additionally, the formation of BCC Ta-Nb-rich and hexagonal-close-packed (HCP) Hf-Zr-rich precipitates are studied as a function of annealing time at 700 °C using a combination of atom probe tomography, transmission electron microscopy, and X-ray diffraction. We found that these BCC and HCP precipitates have preferred orientations with the BCC matrix.
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To study the possible genetic associations with adverse drug reactions (ADR), the Singapore Health Sciences Authority (HSA) has piloted a program to collect DNA and phenotype data of ADR cases as ...part of its pharmacovigilance program. Between 2009 and 2012, HSA screened 158 cases of Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). To assess the association between HLA-B*1502 and carbamazepine (CBZ)-induced SJS/TEN, 13 cases and 26 drug-tolerant controls were analyzed. All 13 CBZ-SJS/TEN cases and 3/26 controls were HLA-B*1502 positive (odds ratio 181, 95% confidence interval: 8.7-3785, P=6.9 × 10(-8)). Discussions of the finding with the Ministry of Health and an expert panel led to the decision to make HLA-B*1502 testing the standard of care prior to first use of CBZ in Asians and to subsidize the genotyping test at public hospitals. This program illustrates the role of a regulatory authority in advancing the use of pharmacogenetics for drug safety.
Abstract In the present study, polycaprolactone–tricalcium phosphate (PCL/TCP) scaffolds with two different fibre laydown patterns, which were coated with hydroxyapatite and gelatine, were used as an ...approach for optimizing bone regeneration in a critical-sized calvarial defect. After 12 weeks, bone regeneration was quantified using microcomputed tomography (micro-CT) analysis, biomechanical testing, and histological evaluation. Notably, the experimental groups with coated scaffolds showed lower bone formation and lower biomechanical properties within the defect compared to the uncoated scaffolds. Surprisingly, the different laydown pattern of the fibres resulted in different bone formation and biomechanical properties: the 0°/60°/120° scaffolds revealed lower bone formation and biomechanical properties compared to the 0°/90° scaffolds in all the experimental groups. Therefore, future bone regeneration strategies utilizing scaffolds should consider scaffold architecture as an important factor during the scaffold optimization stages in order to move closer to a clinical application.
Abstract
The Tb
1−x
Y
x
Mn
2
Ge
2
series (x = 0, 0.1, 0.2) compounds are found to exhibit two magnetic phase transitions with decreasing temperature: from the paramagnetic state to the ...antiferromagnetic interlayer state at T
N
inter
and from an antiferromagnetic interlayer structure to a collinear ferrimagnetic interlayer structure at T
C
inter
. Compared with the slight change of T
N
inter
(409 K, 410 K and 417 K for x = 0, 0.1 and 0.2 respectively), the replacement of Y for Tb leads to a significant decrease in T
C
inter
from 97.5 K for x = 0 to 74.6 K for x = 0.2. The variation in T
C
inter
can be ascribed to the combination of two effects: (1) chemical pressure and (2) magnetic dilution effect by Y substitution for Tb. Besides, a strong anisotropic magnet-volume effect has been detected around T
C
inter
in all compounds with Δa/a = 0.125%, 0.124% and 0.130% for x = 0, 0.1 and 0.2, respectively while no obvious effect is detected along the c-axis. The maximum magnetic entropy change were found to be −ΔS
max
= 9.1 J kg
−1
K
−1
, 11.9 J kg
−1
K
−1
and 6.3 J kg
−1
K
−1
with a field change from 0 T to 5 T for x = 0, 0.1, 0.2 respectively.
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