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71.
Zipora Tietel Sarit Melamed Noy Eretz-Kdosha Ami Guetta Raanan Gvirtz Navit Ogen-Shtern Arnon Dag Guy Cohen 《Molecules (Basel, Switzerland)》2021,26(19)
Jojoba (Simmondsia chinensis (Link) Schneider) wax is used for various dermatological and pharmaceutical applications. Several reports have previously shown beneficial properties of Jojoba wax and extracts, including antimicrobial activity. The current research aimed to elucidate the impact of Jojoba wax on skin residential bacterial (Staphylococcus aureus and Staphylococcus epidermidis), fungal (Malassezia furfur), and virus infection (herpes simplex 1; HSV-1). First, the capacity of four commercial wax preparations to attenuate their growth was evaluated. The results suggest that the growth of Staphylococcus aureus, Staphylococcus epidermidis, and Malassezia furfur was unaffected by Jojoba in pharmacologically relevant concentrations. However, the wax significantly attenuated HSV-1 plaque formation. Next, a complete dose–response analysis of four different Jojoba varieties (Benzioni, Shiloah, Hatzerim, and Sheva) revealed a similar anti-viral effect with high potency (EC50 of 0.96 ± 0.4 µg/mL) that blocked HSV-1 plaque formation. The antiviral activity of the wax was also confirmed by real-time PCR, as well as viral protein expression by immunohistochemical staining. Chemical characterization of the fatty acid and fatty alcohol composition was performed, showing high similarity between the wax of the investigated varieties. Lastly, our results demonstrate that the observed effects are independent of simmondsin, repeatedly associated with the medicinal impact of Jojoba wax, and that Jojoba wax presence is required to gain protection against HSV-1 infection. Collectively, our results support the use of Jojoba wax against HSV-1 skin infections. 相似文献
72.
Natural convection in a fluid saturated porous medium has been numerically investigated using a generalized non-Darcy approach.
The governing equations are solved by using Finite Volume approach. First order upwind scheme is employed for convective formulation
and SIMPLE algorithm for pressure velocity coupling. Numerical results are presented to study the influence of parameters
such as Rayleigh number (106 ≤Ra ≤108), Darcy number (10−5 ≤ Da ≤ 10−2), porosity (0.4 ≤ ɛ ≤ 0.9) and Prandtl number (0.01 ≤ Pr ≤ 10) on the flow behavior and heat transfer. By combining the method of matched asymptotic expansions with computational
fluid dynamics (CFD), so called asymptotic computational fluid dynamics (ACFD) technique has been employed to generate correlation
for average Nusselt number. The technique is found to be an attractive option for generating correlation and also in the analysis
of natural convection in porous medium over a fairly wide range of parameters with fewer simulations for numerical solutions. 相似文献
73.
Dr. Kaushik Kundu Paribesh Acharyya Krishnendu Maji Ranjan Sasmal Prof. Sarit S. Agasti Prof. Kanishka Biswas 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(31):13193-13200
Two-dimensional (2D) lead-free halide perovskites have generated enormous perception in the field of optoelectronics due to their fascinating optical properties. However, an in-depth understanding on their shape-controlled charge-carrier recombination dynamics is still lacking, which could be resolved by exploring the photoluminescence (PL) blinking behaviour at the single-particle level. Herein, we demonstrate, for the first time, the synthesis of nanocrystals (NCs) and 2D nanosheets (NSs) of layered mixed halide, Cs3Bi2I6Cl3, by solution-based method. We applied fluorescence microscopy and super-resolution optical imaging at single-particle level to investigate their morphology-dependent PL properties. Narrow emission line widths and passivation of non-radiative defects were evidenced for 2D layered nanostructures, whereas the activation of shallow trap states was recognized at 77 K. Interestingly, individual NCs were found to display temporal intermittency (blinking) in PL emission. On the other hand, NS showed temporal PL intensity fluctuations within localized domains of the crystal. In addition, super-resolution optical image of the NS from localization-based method showed spatial inhomogeneity of the PL intensity within perovskite crystal. 相似文献
74.
75.
Since ancient times human beings have been conceiving methods that could help reduce the accumulation of undesired fat tissue in their own bodies. Lipocryolysis has already been recognized as an therapy for localized fat reduction by means of a combination of regulated and controlled vacuum and heat extraction therapy. This study was designed to quantify the claimed reduction of local adiposities. For this purpose, 16 treatments were analysed. The data suggested that lipocryolysis is effective for localized reduction of adiposities and that the reduction obtained are measurable. 相似文献
76.
Yihong Fan Benjamin Melamed Yao Zhao Yorai Wardi 《Methodology and Computing in Applied Probability》2009,11(2):159-179
This paper addresses Infinitesimal Perturbation Analysis (IPA) in the class of Make-to Stock (MTS) production-inventory systems with backorders under the continuous-review (R,r) policy, where R is the stock-up-to level and r is the reorder point. A system from this class is traditionally modeled as a discrete system with discrete demand arrivals
at the inventory facility and discrete replenishment orders placed at the production facility. Here, however, we map an underlying
discrete MTS system to a Stochastic Fluid Model (SFM) counterpart in which stochastic fluid-flow rate processes with piecewise constant sample paths replace the corresponding
traditional discrete demand arrival and replenishment stochastic processes, under very mild regularity assumptions. The paper
then analyzes the SFM counterpart and derives closed-form IPA derivative formulas of the time-averaged inventory level and
time-averaged backorder level with respect to the policy parameters, R and r, and shows them to be unbiased. The obtained formulas are comprehensive in the sense that they are computed for any initial
inventory state and any time horizon, and are simple and fast to compute. These properties hold the promise of utilizing IPA
derivatives as an ingredient of offline design algorithms and online management and control algorithms of the class of systems
under study.
相似文献
77.
Babchin A Levich E Melamed M D Y Sivashinsky G 《Colloids and surfaces. B, Biointerfaces》2011,83(1):128-132
Hyperbaric oxygen (HBO) treatment defines the medical procedure when the patient inhales pure oxygen at elevated pressure conditions. Many diseases and all injuries are associated with a lack of oxygen in tissues, known as hypoxia. HBO provides an effective method for fast oxygen delivery in medical practice. The exact mechanism of the oxygen transport under HBO conditions is not fully identified. The objective of this article is to extend the colloid and surface science basis for the oxygen transport in HBO conditions beyond the molecular diffusion transport mechanism. At a pressure in the hyperbaric chamber of two atmospheres, the partial pressure of oxygen in the blood plasma increases 10 times. The sharp increase of oxygen concentration in the blood plasma creates a considerable concentration gradient between the oxygen dissolved in the plasma and in the tissue. The concentration gradient of oxygen as a non-electrolyte solute causes an osmotic flow of blood plasma with dissolved oxygen. In other words, the molecular diffusion transport of oxygen is supplemented by the convective diffusion raised due to the osmotic flow, accelerating the oxygen delivery from blood to tissue. A non steady state equation for non-electrolyte osmosis is solved asymptotically. The solution clearly demonstrates two modes of osmotic flow: normal osmosis, directed from lower to higher solute concentrations, and anomalous osmosis, directed from higher to lower solute concentrations. The fast delivery of oxygen from blood to tissue is explained on the basis of the strong molecular interaction between the oxygen and the tissue, causing an influx of oxygen into the tissue by convective diffusion in the anomalous osmosis process. The transport of the second gas, nitrogen, dissolved in the blood plasma, is also taken into the consideration. As the patient does not inhale nitrogen during HBO treatment, but exhales it along with oxygen and carbon dioxide, the concentration of nitrogen in blood plasma drops and the nitrogen concentration gradient becomes directed from blood to tissue. On the assumption of weak interaction between the inert nitrogen and the human tissue, normal osmosis for the nitrogen transport takes place. Thus, the directions of anomalous osmotic flow caused by the oxygen concentration gradient coincide with the directions of normal osmotic flow, caused by the nitrogen concentration gradient. This leads to the conclusion that the presence of nitrogen in the human body promotes the oxygen delivery under HBO conditions, rendering the overall success of the hyperbaric oxygen treatment procedure. 相似文献
78.
Ohne Zusammenfassung 相似文献
79.
80.
Hrishikesh E. Patel T. Sundararajan Sarit Kumar Das 《Journal of nanoparticle research》2008,10(1):87-97
This work presents a cell model for predicting the thermal conductivity of nanofluids. Effects due to the high specific surface
area of the mono-dispersed nanoparticles and the micro-convective heat transfer enhancement associated with the Brownian motion
of particles are addressed in detail. Novelty of the paper lies in its prediction of the non-linear dependence of thermal
conductivity of nanofluids on particle volume fraction at low particle concentrations. The model is found to correctly predict
the trends observed in experimental data over a wide range of particle sizes, temperatures and particle concentrations. 相似文献