Tuberculosis transmission continues to be a major public health challenge. In this cluster-randomized, controlled trial conducted in Vietnam, active community-wide screening for tuberculosis over 4 ...years is shown to decrease the prevalence of tuberculosis.
•Antibacterial ZnO nanoparticles for edible surface coatings were successfully fabricated.•Incorporation of ZnO nanoparticles in a chitosan/gum arabic edible coating was evaluated.•Effects of ZnO ...nanoparticles on the performance of the edible coating for banana preservation were investigated.•Properties of the edible coating and changes in the physical chemical properties of the banana were investigated.•The developed edible coating composite can be applied for banana preservation.
ZnO nanoparticles are nontoxic inorganic oxides that have been extensively used as a supplement for zinc nutrients and antibacterial agents in the food industry, especially in edible coatings to protect food from deterioration by viruses, fungi, and bacteria. In this work, ZnO nanoparticles were fabricated by a hydrothermal method and characterized by scanning electron microscopy and X-ray diffraction. The prepared ZnO nanoparticles exhibited good antibacterial properties against several bacteria, including Staphylococcus aureus, Escherichia coli, and Bacillus subtilis. The ZnO nanoparticles as an antibacterial agent were incorporated into a chitosan/gum arabic (CH/GA) edible coating, and the protective performance for the preservation of bananas was investigated. The obtained CH/GA/ZnO coating significantly improved the quality and shelf life of bananas at a temperature of 35 °C and relative humidity (RH) of 54 %. The banana surface treated with the CH/GA/ZnO coating was relatively smooth with a CH/GA/ZnO film thickness of approximately 50 μm. The utilization of the resultant coating enabled the maintenance of banana quality, including fruit firmness, weight loss, reducing sugar, and titratable acidity, for a remarkably longer period. The banana coated with the CH/GA/ZnO system was demonstrated to maintain freshness for more than 17 d in comparison with the less than 13 d for the control banana at 35 °C and 54 % RH.
A long-standing controversy is whether autophagy is a bona fide cause of mammalian cell death. We used a cell-penetrating autophagy-inducing peptide, Tat-Beclin 1, derived from the autophagy protein ...Beclin 1, to investigate whether high levels of autophagy result in cell death by autophagy. Here we show that Tat-Beclin 1 induces dose-dependent death that is blocked by pharmacological or genetic inhibition of autophagy, but not of apoptosis or necroptosis. This death, termed “autosis,” has unique morphological features, including increased autophagosomes/autolysosomes and nuclear convolution at early stages, and focal swelling of the perinuclear space at late stages. We also observed autotic death in cells during stress conditions, including in a subpopulation of nutrient-starved cells in vitro and in hippocampal neurons of neonatal rats subjected to cerebral hypoxia–ischemia in vivo. A chemical screen of ∼5,000 known bioactive compounds revealed that cardiac glycosides, antagonists of Na ⁺,K ⁺-ATPase, inhibit autotic cell death in vitro and in vivo. Furthermore, genetic knockdown of the Na ⁺,K ⁺-ATPase α1 subunit blocks peptide and starvation-induced autosis in vitro. Thus, we have identified a unique form of autophagy-dependent cell death, a Food and Drug Administration-approved class of compounds that inhibit such death, and a crucial role for Na ⁺,K ⁺-ATPase in its regulation. These findings have implications for understanding how cells die during certain stress conditions and how such cell death might be prevented.
In vehicular ad hoc networks (VANETs), many schemes for a multi-channel media access control (MAC) protocol have been proposed to adapt to dynamically changing vehicle traffic conditions and deliver ...both safety and non-safety packets. One such scheme is to employ both time-division multiple access (TDMA) and carrier-sense multiple access (CSMA) schemes (called a hybrid TDMA/CSMA scheme) in the control channel (CCH) interval. The scheme can adjust the length of the TDMA period depending on traffic conditions. In this paper, we propose a modified packet transmitted in the TDMA period to reduce transmission overhead under a hybrid TDMA/CSMA multi-channel MAC protocol. Simulation results show that a MAC protocol with a modified packet supports an efficient packet delivery ratio of control packets in the CCH. In addition, we analyze the hybrid TDMA/CSMA multi-channel MAC protocol with the modified packet under saturated throughput conditions on the service channels (SCHs). The analysis results show that the number of neighbors has little effect on the establishment of the number of time slots in TDMA periods and on SCHs under saturated throughput conditions.
A new DEM-based approach is proposed to study the desiccation of slurry soils. Distinctly to existing DEM approaches that only consider the solid phase, the proposed method explicitly models both ...phases, soil and water, using spherical particles to account for their volumetric portions. This new concept allows a close description of slurry soils mimicking actual experiment conditions and providing the capability of simulating suspended soil particles in water including their transformation to the semi-solid state as water evaporates during drying. Furthermore, the water loss can be now explicitly simulated by shrinking water particles, while the solid phase particles remain unchanged. To model the soil-water interaction during drying, an existing liquid bridge force model commonly used in DEM to deal with unsaturated soils is modified to extend its working range to tackle problems involving high water contents. The proposed approach is applied to simulate a desiccation experiment conducted on a Kaolin NY specimen. The results show that the new approach can qualitatively capture main factors controlling the formation and development of the soil curling behaviour observed in this experiment. This study suggests that the new approach can be a promising computational tool to provide insights into the transition behaviour of soils from the slurry to semi-solid states involving saturated and unsaturated soil conditions.
Soil curling is a common phenomenon in nature due to the rearrangement of soil particles caused by moisture loss. The occurrence of curling in soils significantly affects soil performance in various ...disciplines. Despite its importance, most existing studies describe the soil curling process within the context of soil desiccation cracking, where boundary conditions facilitating soil curling are not well controlled, or often use the final stage of the desiccation process to infer the soil curling behaviour. Consequently, the underlying soil curling mechanism, the state of the curled soil, and the influencing factors (i.e., clay type, drying temperature, initial water content, and sand content) are not fully understood. In this study, soil curling tests were conducted to study the above-mentioned issues in different types of soils under well-controlled boundary and environmental conditions. It was found that natural clays consisting of higher portions of smectite underwent both upward curling (concave-up) and downward curling (convex-up), while artificial clay experienced only concave-up curling. Concave-up curling initiated when the samples were almost in the saturated condition, while convex-up curling started when the water content of samples was close to their plastic limits. The influencing factors had a profound effect on the moisture evaporation and thus on the soil curling state and its lift-off height. Finally, a conceptual model isproposed to explain the soil curling mechanism and factors influencing soil curling.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
7.
E2-2 Protein and Fuchs's Corneal Dystrophy Baratz, Keith H; Tosakulwong, Nirubol; Ryu, Euijung ...
The New England journal of medicine,
09/2010, Letnik:
363, Številka:
11
Journal Article
Recenzirano
Odprti dostop
In this genomewide association study of age-related corneal dystrophy, there was a significant association with variants of TCF4, which encodes the E2-2 transcription factor. The risk variant of the ...most strongly associated genetic marker had an odds ratio of approximately 5.
Fuchs's corneal dystrophy (FCD) is a progressive, bilateral condition characterized by dysfunction of the corneal endothelium, leading to reduced vision. The prevalence of FCD has been estimated at about 5% among persons over the age of 40 years in the United States.
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Corneal edema that is associated with FCD may progress after cataract surgery and is the most common indication for the 42,000 corneal transplantations that take place each year in the United States. Enthusiasm for refractive surgery is decreased among patients who are at high risk for FCD.
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Thus, the ability to diagnose FCD before symptoms develop and knowledge . . .
Seepage-induced internal erosion and failure in unsaturated/saturated porous media is challenging for computational simulations as they involve the behaviour, interactions (solid, air, water) and ...transformation (fluidisation and deposition of fines grains) of different phases. Tackling this challenging problem requires correct mathematical descriptions of phase interactions and transformation together with a robust computational framework, both of which are addressed in this paper. The new mathematical model and coupled governing equations based on the continuum mixture theory enable the use of a single set of SPH particles for the descriptions of behaviour, interactions and phase transformation of all five phases of the porous media (soil skeleton, erodible fines particles, fluidised particles, water, and air), including the effect of both saturation and erosion on the shear strength of porous media. A fully explicit and stabilised SPH framework that allows accurate SPH approximations of spatial gradients is proposed for the numerical solutions of coupled governing equations. The proposed computational framework performs well in benchmark tests against available analytical and numerical solutions and achieved reasonable agreements with experiments. Numerical results obtained from the predictions of seepage-induced erosion and failure demonstrate that the proposed computational framework is efficient for addressing challenging problems involving coupled flow-deformation, seepage-induced internal erosions, and large deformation failures of unsaturated/saturated porous media.
•A five-phase mathematical model for internal erosion in porous media is developed.•A robust constitutive model considering erosion on soil’s shear strength is proposed.•A stabilised fully coupled flow deformation SPH erosion framework is proposed.•The new SPH framework can handle seepage erosion-induced failure of porous media
AbstractThe load-carrying capacity of rock-socketed piles depends on the shaft resistance at the pile-rock interface which is governed by the interactions between the pile, rock, and soft interface ...materials (smear or infill). Despite recent advancements in 3D experimental pile testing of smeared interfaces, the knowledge in this field still remains quite limited primarily due to the experimental limitations, and high costs and fabrication challenges associated with extensive laboratory tests. This study presents a comprehensive numerical investigation to simulate 3D rock-socketed piles with smear using the discrete element method (DEM). By correlating the observations with the experimental x-ray CT images, the interactions between the pile, rock and smear are investigated for various smear area proportions in terms of the micromechanics at the asperity level. The movements of smear and rock debris in the socket and their influence on the various asperity failure modes in relation to the shaft resistance development are evaluated by monitoring the force and damage evolution in DEM. Finally, the calibrated DEM model is utilized to examine the influence of the various smear fabric parameters on the shaft response. Based on the observations, it was inferred that the shear failure mode primarily dictates the interface damage evolution, with a significant contribution from mixed-mode failure involving both tensile and shear damages. Insights from the results indicated that the effect of smear placement on the load-bearing capacity of the pile is found to be minimal compared to the other smear fabric parameters (thickness and area proportion). Moreover, the critical smear thickness to asperity height ratio was determined to be 1.75 beyond which the smear controls the load-bearing capacity of the pile. The discussions presented in this study provide a novel understanding into the smear fabric effect and act as a foundation for further research aimed at improving the reliability and efficiency of rock-socketed pile construction in soft rocks.
Nata de coco produced via coconut water fermentation using Acetobacter xylinum was directly applied to remove metal cations in aqueous solutions without any further chemical modification. Bacterial ...cellulose, contributing just 0.8 wt % to nata de coco, were randomly distributed and interconnected, yielding a three‐dimensional framework with high crystallinity and porosity. Due to these characteristics and the abundant presence of electron‐rich hydroxyl groups, unmodified bacterial cellulose in nata de coco exhibited a strong affinity to metal cations in water. The adsorption efficiency of nata de coco can be significantly improved to ∼30 and ∼45 mg g−1 for Pb2+ and Fe3+, respectively, by decreasing its size by grinding to decrease its size. Notably, nata de coco can adsorb multiple cations and the uptakes were almost similar for a 100‐fold scaled‐up adsorption volume.
Pristine nata de coco as produced via the fermentation of coconut water was applied to the adsorption of metal cations in aqueous solutions. Nata de coco containing unmodified bacterial cellulose in a 3D framework could simultaneously adsorb many metal cations in various experimental scales, providing a simple, inexpensive and efficient method to remove contaminated toxic metals from water.
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