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41.
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
42.
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
43.
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
44.
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
45.
Ohne Zusammenfassung 相似文献
46.
47.
This paper introduces a new class of real vector-valued stochastic processes, called MARM (Multivariate Autoregressive Modular) processes, which generalizes the class of (univariate) ARM (Autoregressive Modular) processes. Like ARM processes, the key advantage of MARM processes is their ability to fit a strong statistical signature consisting of first-order and second-order statistics. More precisely, MARM processes exactly fit an arbitrary multi-dimensional marginal distribution and approximately fit a set of leading autocorrelations and cross-correlations. This capability appears to render the MARM modeling methodology unique in its ability to fit a multivariate model to such a class of strong statistical signatures. The paper describes the construction of two flavors of MARM processes, MARM + and MARM ? , studies the statistics of MARM processes (transition structure and second order statistics), and devises MARM-based fitting and forecasting algorithms providing point estimators and confidence intervals. The efficacy of the MARM fitting and forecasting methodology will be illustrated on real-life data in a companion paper. 相似文献
48.
Radical Polymerization of the Silene (Me3Si)2SiCR2 by Hydrogen Transfer from a Trimethylsilyl Group
Dmitry Bravo‐Zhivotovskii Dr. Semyon Melamed Victoria Molev Nadejda Sigal Dr. Boris Tumanskii Dr. Mark Botoshansky Dr. Gregory Molev Yitzhak Apeloig Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(10):1834-1837
The silene (Me3Si)2Si?Ad is polymerized to produce a polycarbosilane with an unusual Si? Si? C repeating backbone, rather than the Si? C or Si? Si? C? C units expected for olefinic radical polymerization. The polymer structure and the polymerization mechanism (see scheme) were studied by GPC, EPR, and NMR spectroscopy and by trapping experiments.
49.
50.
Vinyl carbanions derived from cis-cinnamonitrile 1 were formed by reacting it with lithium diisopropylamide (LDA) as a base in aprotic solvents at low temperatures; reaction with various electrophiles (E) resulted in the corresponding derivatives PhCHC(E)CN. The configurational stability of the vinyl carbanions derived from 1 and the geometry of the reaction products was affected by the solvating properties of the medium. Retention of configuration was achieved in a poor solvating medium-diethyl ether-hexane (4:1). Addition of a crown ether or using THF as solvent resulted in products having trans geometry. The site of deprotonation of cinnamonitrile (cis and trans) was compared to that of cinnamic esters and discussed. Determination of the geometry of the products was based on their 1H NMR spectra. 相似文献