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41.
Taking functional scientific devices and metal-based nanoparticles into account, the present research was carried out to evaluate the plant (Capsicum annuum) responses to cold plasma and zinc oxide nanoparticle (nZnO) in in vitro and pot conditions. Seeds were exposed to plasma (0.84 W/cm2 surface power densities) with three exposure times (0, 60, and 120 s) and/or two concentrations of nZnO (0 and 100 mgl??1). The treated seeds were cultured in hormone-free MS medium (MS) or supplemented with 2 mgl??1 BA and 0.5 mgl??1 IAA (MSH). The seed pre-treatment with plasma enhanced a germination process and plant early growth, in contrast with the nZnO treatment. The treatment of nZnO significantly decreased the total fresh mass and leaf area in the seedlings grown in both culture media, while its growth-delaying impact was mitigated by the plasma treatment. The chlorophyll a and carotenoid were increased to 39.35 and 32% for the plasma-treated seedlings, respectively, than the control. The plasma and/or nZnO treatments acted as effective elicitors to induce the peroxidase activities in both culture media. Similarly, the activities of phenylalanine ammonia-lyase and soluble phenols were found to be significantly higher in the plasma and/or nZnO groups in both roots and leaves. Interestingly, inhibiting effects of nZnO on xylem differentiation was alleviated by the plasma treatments. In the pot condition, soaking seeds before the plasma treatment was the most effective method to affect plant growth. This is a first report reflecting the potential benefits of the cold plasma treatment to improve plant growth and resistance to the nanoparticle.  相似文献   
42.
The present study was carried out to investigate the impact of climate change on land suitability for agricultural development in a sub-basin of Karkheh River Basin, Iran. For this, land suitability of the sub-basin was evaluated twice; once regardless of the climate change impact, and again by involving the impact of climate change. Simple Limitation Approach was used to evaluate the suitability of the sub-basin for cultivation of winter wheat. According to the results, around 22.57% (124121.16 ha) of the study area is suitable for cropping while the capability of 39.29% (216086.13 ha) of the sub-basin was evaluated to be poor/moderate for this purpose. In this research, in order to investigate the impact of climate change on farmlands, the changing trend of the four variables of maximum and minimum temperature, precipitation, and radiation were stimulated by the year 2039 using downscaled interpolation of IPCM general circulation model under three emission scenarios of A1B, A2, and B1. The stimulation was done by LARS-WG Software. The overlaying was done once more, but this time using the stimulated values. Comparing the current and stimulated land suitability maps revealed the fact that, in the most pessimistic future under A1B scenario, approximately 15.51% (85288.95 ha) of the study area will lose its capability for farming as a result of an increase of 1.3?C in temperature, and a decrease of 20.43% mm in total precipitation. The research finding emphasizes the risk of climate change on land health for farming purposes.  相似文献   
43.

Background

Surgical tasks are performed in a sequence of steps, and technical skill evaluation includes assessing task flow efficiency. Our objective was to describe differences in task flow for expert and novice surgeons for a basic surgical task.

Methods

We used a hierarchical semantic vocabulary to decompose and annotate maneuvers and gestures for 135 instances of a surgeon’s knot performed by 18 surgeons. We compared counts of maneuvers and gestures, and analyzed task flow by skill level.

Results

Experts used fewer gestures to perform the task (26.29; 95% CI = 25.21 to 27.38 for experts vs. 31.30; 95% CI = 29.05 to 33.55 for novices) and made fewer errors in gestures than novices (1.00; 95% CI = 0.61 to 1.39 vs. 2.84; 95% CI = 2.3 to 3.37). Transitions among maneuvers, and among gestures within each maneuver for expert trials were more predictable than novice trials.

Conclusions

Activity segments and state flow transitions within a basic surgical task differ by surgical skill level, and can be used to provide targeted feedback to surgical trainees.  相似文献   
44.
There are many published studies presenting ethanol and acetone as PHAs‐poor solvents, where these two solvents are shown to dissolve <2% (w/v) of PHAs at low temperatures. In this study, the suitability of ethanol and acetone for the recovery of PHB at different temperatures (from room temperature to near boiling point) in Cupriavidus necator was investigated. Experiments were performed using response surface methodology to examine the effects of different temperatures and heating incubation times on recovery percentage using the two solvents. The highest recovery percentage (92.3%) and product purity (up to 99%) were obtained with ethanol‐assisted extraction at 76°C for 32 min of incubation time. Under these conditions the extracted PHB exhibited a molecular mass of 1.2 × 106. The present strategy showed that at temperatures near its boiling point, ethanol, as a nonhalogenated solvent, represents a good alternative to halogenated solvents, like chloroform, when PHB recovery is concerned. DSC analysis showed good thermal properties for ethanol‐ and acetone‐extracted biopolymers. GC and 1H NMR analysis confirmed the extracted biopolymer to be polyhydroxybutyrate of good purity. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1480–1486, 2016  相似文献   
45.
International Journal of Peptide Research and Therapeutics - Coxiella burnetii pathogen, which causes Q fever, is one of the most dangerous pathogens transmitted from the livestock to humans. The...  相似文献   
46.
47.
Aminoglycoside antibiotics are widely used against Gram‐negative infections. On the other hand, nephrotoxicity is a deleterious side effect associated with aminoglycoside therapy. Gentamicin is the most nephrotoxic aminoglycoside. Because of serious health complications ensue the nephrotoxicity induced by aminoglycosides, finding new therapeutic strategies against this problem has a great clinical value. This study has attempted to compare the nephrotoxic properties of gentamicin and a new nanosized formulation of this drug in a mice model. Animals were treated with gentamicin (100 mg/kg, i.p. for eight consecutive days) and nanogentamicin (100 mg/kg, i.p. for eight consecutive days). Blood urea nitrogen (BUN), plasma creatinine levels, and histopathological changes of kidney proximal tubule were monitored. It was found that gentamicin caused severe degeneration of kidney proximal tubule cells and an increase in serum creatinine and BUN. No severe injury was observed after nanogentamicin administration. This study proved that nanosized gentamicin is less nephrotoxic.  相似文献   
48.
49.
There is growing evidence that the complement activation product C5a positively or negatively regulates inflammatory functions. The studies presented here report that C5a exerts anti-inflammatory effects by altering production of the cytokines IL-17A and IL-23 during endotoxic shock in young adult male C57BL/6J mice and has similar effects on macrophages from the same mice. IL-17A and IL-23 both appeared in plasma during endotoxemia, and their neutralization improved survival. The relevant sources of IL-17A during endotoxemia were not CD4(+) cells, γδ T cells, or NK cells but CD11b(+)F4/80(+) macrophages. The addition in vitro of C5a to lipopolysaccharide-activated peritoneal macrophages dose dependently antagonized the production of IL-17A (IC(50), 50-100 nM C5a) and IL-23 (IC(50), 10 nM C5a). This suppression required the receptor C5aR, but was independent of the second C5a receptor, C5L2. Genetic absence of C5aR was associated with much higher levels of IL-17A and IL-23 during endotoxic shock. Mechanistically, C5a mediated its effects on the IL-17A/IL-23 axis in a 2-step process. C5a caused activation of the PI3K-Akt and MEK1/2-ERK1/2 pathways, resulting in induction of IL-10, which powerfully inhibited production of IL-17A and IL-23. These data identify previously unknown mechanisms by which the anaphylatoxin C5a limits acute inflammation and antagonizes the IL-17A/IL-23 axis.  相似文献   
50.
Human embryonic stem cell (hESC) lines are derived from the inner cell mass (ICM) of preimplantation human blastocysts obtained on days 5–6 following fertilization. Based on their derivation, they were once thought to be the equivalent of the ICM. Recently, however, studies in mice reported the derivation of mouse embryonic stem cell lines from the epiblast; these epiblast lines bear significant resemblance to human embryonic stem cell lines in terms of culture, differentiation potential and gene expression. In this study, we compared gene expression in human ICM cells isolated from the blastocyst and embryonic stem cells. We demonstrate that expression profiles of ICM clusters from single embryos and hESC populations were highly reproducible. Moreover, comparison of global gene expression between individual ICM clusters and human embryonic stem cells indicated that these two cell types are significantly different in regards to gene expression, with fewer than one half of all genes expressed in both cell types. Genes of the isolated human inner cell mass that are upregulated and downregulated are involved in numerous cellular pathways and processes; a subset of these genes may impart unique characteristics to hESCs such as proliferative and self-renewal properties.  相似文献   
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