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51.
Antiviral activity of Ragusano donkeys' milk proteins was investigated for the effect on echovirus type 5, known to infect the gastrointestinal tract of humans. Three protein fractions were tested; casein (CN), whey protein (WP) and a low molecular whey protein fraction (LWP; <30,000 Da). The antiviral activity of WP and LWP was tested on echovirus type 5 at three concentrations (1, 5 and 10 mg mL?1); CN was assessed only at the lower concentration. All donkey milk protein fractions showed significant inhibition on virus replication at the concentration of 1 mg mL?1, and both WP and LWP fractions showed significant inhibition on the virus replication at all concentrations tested. The strongest antiviral effect was observed for the WP fraction. These findings show that the different whey proteins in donkey milk, probably acting in synergy, exert antiviral activity on echovirus 5 and might contribute to prevent gastrointestinal virus infections in humans.  相似文献   
52.
A sample of 203 intellectually gifted adolescents (top 1%) were administered the Allport-Vernon-Lindzey (1970) Study of Values (SOV) at age 13; 20 years later, they were administered the SOV again. In this study, researchers evaluated the intra- and interindividual temporal stability of the 6 SOV themes, namely, Theoretical (T), Economic (E), Political (P), Aesthetic (A), Social (S), and Religious (R). Over the 20-year test-retest interval, the SOV's mean and median interindividual correlations for the 6 themes were .37 and .34, respectively. Correspondingly, the mean and median of all 203 intraindividual correlations were .30 and .39. Configural analyses of the most dominant theme at age 13 revealed that this theme was significantly more likely than chance to be dominant or adjacent to the dominant theme at age 33. Adjacency was ascertained through a number of empirically based auxiliary analyses of the SOV, revealing 2 robust gender-differentiating clusters: T-E-P for males and A-S-R for females. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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A method to separate squalene from palm fatty acid distillate (PFAD) using neutralization‐hydrolysis‐neutralization before employing adsorption column chromatography was developed. Extraneous matters, especially free fatty acids (83.8%) and acylglycerols (12.7%), were first neutralized and removed before being subjected to hydrolysis by using commercially available, immobilized Candida antartica lipase, at 65 °C for 8 h. Neutralization followed by hydrolysis and repeated neutralization successfully concentrated squalene from an initial amount of 3.76% to 27.5%. Oil extracted from neutralized‐hydrolyzed‐neutralized PFAD was then passed through a Diaion HP‐20 column using reverse‐phase adsorption chromatography. Squalene was desorbed by hexane, with a recovery of 93%.  相似文献   
55.
The control and rational design of redox‐based memristive devices, which are highly attractive candidates for next‐generation nonvolatile memory and logic applications, is complicated by competing and poorly understood switching mechanisms, which can result in two coexisting resistance hystereses that have opposite voltage polarity. These competing processes can be defined as regular and anomalous resistive switching. Despite significant characterization efforts, the complex nanoscale redox processes that drive anomalous resistive switching and their implications for current transport remain poorly understood. Here, lateral and vertical mapping of O vacancy concentrations is used during the operation of such devices in situ in an aberration corrected transmission electron microscope to explain the anomalous switching mechanism. It is found that an increase (decrease) in the overall O vacancy concentration within the device after positive (negative) biasing of the Schottky‐type electrode is associated with the electrocatalytic release and reincorporation of oxygen at the electrode/oxide interface and is responsible for the resistance change. This fundamental insight presents a novel perspective on resistive switching processes and opens up new technological opportunities for the implementation of memristive devices, as anomalous switching can now be suppressed selectively or used deliberately to achieve the desirable so‐called deep Reset.  相似文献   
56.
The taxonomic assemblage and functions of the plant bacterial community are strongly influenced by soil and host plant genotype. Crop breeding, especially after the massive use of nitrogen fertilizers which led to varieties responding better to nitrogen fertilization, has implicitly modified the ability of the plant root to recruit an effective bacterial community. Among the priorities for harnessing the plant bacterial community, plant genotype-by-microbiome interactions are stirring attention. Here, we analyzed the effect of plant variety and fertilization on the rhizosphere bacterial community. In particular, we clarified the presence in the bacterial community of a varietal effect of N and P fertilization treatment. 16S rRNA gene amplicon sequence analysis of rhizospheric soil, collected from four wheat varieties grown under four N-P fertilization regimes, and quantification of functional bacterial genes involved in the nitrogen cycle (nifH; amoA; nirK and nosZ) were performed. Results showed that variety played the most important role and that treatments did not affect either bacterial community diversity or bacterial phyla abundance. Variety-specific response of rhizosphere bacterial community was detected, both in relation to taxa (Nitrospira) and metabolic functions. In particular, the changes related to amino acid and aerobic metabolism and abundance of genes involved in the nitrogen cycle (amoA and nosZ), suggested that plant variety may lead to functional changes in the cycling of the plant-assimilable nitrogen.  相似文献   
57.
Endocrine-disrupting chemicals (EDCs) are different natural and synthetic chemicals that may interfere with several mechanisms of the endocrine system producing adverse developmental, metabolic, reproductive, and neurological effects in both human beings and wildlife. Among pesticides, numerous chemicals have been identified as EDCs. MicroRNAs (miRNAs) can regulate gene expression, making fine adjustments in mRNA abundance and regulating proteostasis. We hypothesized that exposure to low doses of atrazine, cypermethrin, and vinclozolin may lead to effects on miRNA expression in SH-SY5Y cells. In particular, the exposure of SH-SY5Y cells to subtoxic concentrations of vinclozolin is able to downregulate miR-29b-3p expression leading to the increase in the related gene expression of ADAM12 and CDK6, which may promote a pro-oncogenic response through the activation of the PI3K/Akt/mTOR pathway and counteracting p53 activity. A better understanding of the molecular mechanisms of EDCs could provide important insight into their role in human disease.  相似文献   
58.
Herein, a simple, solvent-free method to fabricate polymer-encapsulated halide perovskite photoconductors is described. Dry mechanochemical synthesis is used to prepare CsPbBr3 in the presence of poly(butyl methacrylate) (PBMA). The resulting composite powder is then heated and pressed into a free-standing disk with a thickness controlled by a metallic spacer ring. The disk can be laminated on a glass substrate patterned with interdigitated electrodes, resulting in a planar photoconductor device. The best photoconductive performance is obtained for disks that consist of 75 wt.% CsPbBr3 in PBMA, reaching a detectivity of ≈2 × 1011 Jones. Moreover, by adjusting the thickness of the disk, narrowband detectors can be obtained due to charge collection narrowing. Depending on the thickness of the pressed disk, the position and width of the detectivity peak can be tuned. At last, the disks are tested as possible absorber materials for X-ray detectors, where ow detection limit, and fast and linear response are measured for perovskite-polymer disks with 50 wt.% perovskite content. This work shows a simple and versatile approach toward the fabrication of halide perovskite photodetectors, which can be carried out in air and without the use of solvents.  相似文献   
59.
The detection of ROS1 and ALK rearrangements is performed for advanced-stage non-small cell lung cancer. Several techniques can be used on cytological samples, such as immunocytochemistry (ICC), fluorescence in situ hybridization (FISH) and, more recently, next-generation sequencing (NGS), which is gradually becoming the gold standard. We performed a retrospective study to compare ALK and ROS1 rearrangement results from immunocytochemistry, FISH and NGS methods from 131 cytological samples. Compared to NGS, the sensitivity and specificity of ICC were 0.79 and 0.91, respectively, for ALK, and 1 and 0.87 for ROS1. Regarding FISH, the sensitivity and specificity were both at 1 for ALK and ROS1 probes. False-positive cases obtained by ICC were systematically corrected by FISH. When using ICC and FISH techniques, results are very close to NGS. The false-positive cases obtained by ICC are corrected by FISH, and the true-positive cases are confirmed. NGS has the potential to improve the detection of ALK and ROS1 rearrangements in cytological samples; however, the cost of this technique is still much higher than the sequential use of ICC and FISH.  相似文献   
60.
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