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1.

In this research work, a systematic design of a novel anti-reflective layer using embedded plasmonic nanoparticles is investigated for a thin-film GaAs solar cell. First, an anti-reflective layer that is made from ITO or SiO2 is assumed in which Al nanoparticles are embedded inside them to manipulate the absorption and hence the photocurrent of a 500-nm GaAs solar cell. It is investigated that the Al nanoparticles embedded inside the anti-reflective coating improve the photocurrent of a GaAs solar cell. For instance, the 15.37 mA photocurrent is obtained for 500-nm bare GaAs cell, and it reached to 17.25 mA/cm2 and 20.18 mA/cm2 when an ITO anti-reflection is used with Al nanoparticles on top and inside that, respectively. It increases to 21.94 mA/cm2 and 24.98 mA/cm2 in the case of the anti-reflective layer made from SiO2 and Al nanoparticles at the top side or inside that, respectively. Finally, using a double anti-reflective layer that is made from SiO2-TiO2, the maximum photocurrents of 23.79 mA/cm2 and 24.68 mA /cm2 are obtained when Al nanoparticles are at the top side or inside that, respectively. The simulation results show that the embedding Al nanoparticles in the anti-reflective layer can improve the photocurrent of a thin-film GaAs solar cell.

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2.
Two series of new 4-aminopyrimido[4,5-b]indole ribonucleosides bearing phenyl or hetaryl group at position 5 or 6 have been prepared by Suzuki or Stille cross-coupling reactions employing X-Phos ligand with (het)arylboronic acids or stannanes. A series of 4-substituted nucleosides has been also prepared by Pd-catalyzed cross-couplings or nucleophilic substitution. Some of these compounds displayed moderate antiviral activities against HCV and dengue viruses.  相似文献   
3.
As part of a virus discovery investigation using a metagenomic approach, a highly divergent novel Human papillomavirus type was identified in pooled convenience nasal/oropharyngeal swab samples collected from patients with febrile respiratory illness. Phylogenetic analysis of the whole genome and the L1 gene reveals that the new HPV identified in this study clusters with previously described gamma papillomaviruses, sharing only 61.1% (whole genome) and 63.1% (L1) sequence identity with its closest relative in the Papillomavirus episteme (PAVE) database. This new virus was named HPV_SD2 pending official classification. The complete genome of HPV-SD2 is 7,299 bp long (36.3% G/C) and contains 7 open reading frames (L2, L1, E6, E7, E1, E2 and E4) and a non-coding long control region (LCR) between L1 and E6. The metagenomic procedures, coupled with the bioinformatic methods described herein are well suited to detect small circular genomes such as those of human papillomaviruses.  相似文献   
4.

In this paper, cylindrical shape coupled bimetallic plasmonic nanoparticles (NPs) were used to improve the performance of a thin-film silicon solar cell. Our design is based on the appropriate selection of the composition and morphology of the NPs to reach a cell with excellent optical properties. The specific interaction between the incident light and bimetallic NPs helps us to design better solar absorbers. Here, the FDTD method was used to evaluate the effect of cylindrical Al-Ag bimetallic NPs on the surface of a thin silicon absorber. At first, a unit cell with Al-Al paired nano-cylinders at the surface was evaluated and a photocurrent of 14.65 mA/cm2 was obtained. In the case of a cell with paired Al-Ag bimetallic nano-cylinders, the photocurrent was increased to 16.15 mA/cm2. This value was increased to 16.57 mA/cm2 when paired polymetallic NPs were used. According to the results of this work, bimetallic and polymetallic nanoparticles can significantly improve the photocurrent of an ultra-thin silicon solar cell. The results of this work can be used to design better plasmonic-based light trapping systems for thin-film solar cells.

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5.
Gastric cancer is a life-threatening disease; resulting from interaction among genetic, epigenetic, and environmental factors. Aberrant dysregulation and methylation changes in Wnt/β-catenin signaling downstream elements are a prevalent phenomenon encountered in gastric tumorigenesis. Also, viral infections play a role in gastric cancer development. CTNNBIP1 (β-catenin interacting protein 1) gene is an antagonist of Wnt signaling which binds to the β-catenin molecules. The CTNNBIP1 function as tumor suppressor gene or oncogene in different types of cancer is controversial. Moreover, its function and regulatory mechanisms in gastric cancer progression is unknown. In the present study, we examined CTNNBIP1 gene expression, the methylation status of the regulatory region of the gene, and their association with Epstein–Barr virus (EBV), and cytomegalovirus (CMV) and Helicobacter pylori infections in human gastric adenocarcinoma tissues in comparison with their adjacent nontumoral tissues. Our data revealed a significant downregulation of CTNNBIP1 in gastric tumors. Female patients showed lower level of CTNNBIP1 than males (p < 0.05). Also, decreased expression of CTNNBIP1 was markedly associated with well-differentiated tumor grades (p < 0.05). No methylation change was observed between tumoral and nontumoral tissues. Additionally, CTNNBIP1 down regulation was significantly associated with CMV infection (p < 0.05). In the absence of EBV infection, lower expression of CTNNBIP1 was observed. There was no association between H. pylori infection and CTNNBIP1 expression. Our findings revealed the tumor suppressor role for CTNNBIP1 in gastric adenocarcinoma. Interestingly, EBV and CMV infections modulate CTNNBIP1 expression.  相似文献   
6.
A change of mind in response to social influence could be driven by informational conformity to increase accuracy, or by normative conformity to comply with social norms such as reciprocity. Disentangling the behavioural, cognitive, and neurobiological underpinnings of informational and normative conformity have proven elusive. Here, participants underwent fMRI while performing a perceptual task that involved both advice-taking and advice-giving to human and computer partners. The concurrent inclusion of 2 different social roles and 2 different social partners revealed distinct behavioural and neural markers for informational and normative conformity. Dorsal anterior cingulate cortex (dACC) BOLD response tracked informational conformity towards both human and computer but tracked normative conformity only when interacting with humans. A network of brain areas (dorsomedial prefrontal cortex (dmPFC) and temporoparietal junction (TPJ)) that tracked normative conformity increased their functional coupling with the dACC when interacting with humans. These findings enable differentiating the neural mechanisms by which different types of conformity shape social changes of mind.

When we change our mind in response to other people’s opinion, we may be motivated to be correct or to have a good relationship with others. This fMRI study disentangles the neurobiological underpinnings of these two different motives in the human brain, and shows that the second motive is absent when we interact with computers.  相似文献   
7.
Abstract: The diverse physiological actions of galanin are thought to be mediated through activation of galanin receptors (GalRs). We report the genomic and cDNA cloning of a mouse GalR that possesses a genomic structure distinct from that of GalR1 and encodes a functional galanin receptor. The mouse GalR gene consists of two exons separated by a single intron within the protein-coding region. The splicing site for the intron is located at the junction between the third transmembrane domain and the second intracellular loop. The cDNA encodes a 370-amino acid putative G protein-coupled receptor that is markedly different from human GalR1 and rat GalR3 (38 and 57%) but shares high homology with rat GalR2 (94%). In binding studies utilizing membranes from COS-7 cells transfected with mouse GalR2 cDNA, the receptor displayed high affinity ( K D = 0.47 n M ) and saturable binding with 125I-galanin ( B max = 670 fmol/mg). The radioligand binding can be displaced by galanin and its analogues in a rank order: galanin ⋍ M40 ⋍ M15 ⋍ M35 ⋍ C7 ⋍ galanin (2–29) ⋍ galanin (1–16) ≫ galanin (10–29) ⋍ galanin (3–29), which resembles the pharmacological profile of the rat GalR2. Receptor activation by galanin in COS-7 cells stimulated phosphoinositide metabolism, which was not reversed by pertussis toxin. Thus, the galanin receptor encoded in the cloned mouse GalR gene is the type 2 galanin receptor and is active in both ligand binding and signaling assays.  相似文献   
8.
There is an urgent need for the development of novel antimicrobial agents that offer effective treatment against MRSA. Using a new class of dipeptide antibiotic TAN-1057A/B as lead, we designed, synthesized and evaluated analogs of TAN-1057A/B. Several novel dihydropyrimidinone antibiotics demonstrating comparable antibiotic efficacy while possessing favorable selectivity were identified.  相似文献   
9.
Bahador N  Baserisalehi M 《Anaerobe》2011,17(6):358-360
The family of Enterobacteriaceae is a major group of gram negative bacteria, some of these microorganisms are pathogen and could cause disease mainly gastroenteritis. Recently, due to drug resistant nature of these bacteria specially in developing countries treatment of the patient considered as important investigate. Quercus castaneifolia is a native plant of Yasuj province in Iran, which the people who living in this area consume the fruit of this plant for treatment of enteric disease. Hence, the present study was conducted to evaluate the effect of fruit of Q. castaneifolia extract on pathogenic enteric bacteria viz., E. coli, Salmonella typhimurium, Shigella dysenteriae and Yersinia enterocolitica.Antimicrobial susceptibility and minimal inhibitory concentration (MIC) of the extracts were assessed by gel diffusion method and modification of E-test respectively. All the experiments were performed in triplicate and the statistical analysis was carried out on the results. The results obtained from this study indicated that alcoholic extract was shown antimicrobial effect on the microorganisms tested. In addition, S. dysentriae was more sensitive with zone of inhibition 18 mm and MIC value was 2.5 × 10−4 whereas, E. coli was less sensitive with zone of inhibition 12 mm and MIC value 1 × 10−2. Salmonella typhimurium and Yersinia enterocolitica showed relatively intermediate susceptibility to the extract with zone of inhibition of 14 mm and MIC value 5 × 10−3. Overall, Q. castaneifolia may be considered for treatment of the patients suffering from enteric disease.  相似文献   
10.
The Line Islands are calcium carbonate coral reef platforms located in iron-poor regions of the central Pacific. Natural terrestrial run-off of iron is non-existent and aerial deposition is extremely low. However, a number of ship groundings have occurred on these atolls. The reefs surrounding the shipwreck debris are characterized by high benthic cover of turf algae, macroalgae, cyanobacterial mats and corallimorphs, as well as particulate-laden, cloudy water. These sites also have very low coral and crustose coralline algal cover and are call black reefs because of the dark-colored benthic community and reduced clarity of the overlying water column. Here we use a combination of benthic surveys, chemistry, metagenomics and microcosms to investigate if and how shipwrecks initiate and maintain black reefs. Comparative surveys show that the live coral cover was reduced from 40 to 60% to <10% on black reefs on Millennium, Tabuaeran and Kingman. These three sites are relatively large (>0.75 km2). The phase shift occurs rapidly; the Kingman black reef formed within 3 years of the ship grounding. Iron concentrations in algae tissue from the Millennium black reef site were six times higher than in algae collected from reference sites. Metagenomic sequencing of the Millennium Atoll black reef-associated microbial community was enriched in iron-associated virulence genes and known pathogens. Microcosm experiments showed that corals were killed by black reef rubble through microbial activity. Together these results demonstrate that shipwrecks and their associated iron pose significant threats to coral reefs in iron-limited regions.  相似文献   
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