Atomic Layer Deposition of TiO2 on Si Window Enables In Situ ATR-SEIRAS Measurements in Strong Alkaline Electrolytes.

The Si window is the most widely used internal reflection element (IRE) for electrochemical attenuated total reflection surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS), yet local chemical etching on Si by concentrated OH- anions bottlenecks the reliable application of this method in strong alkaline electrolytes. In this report, atomic layer deposition of a 25 nm nonconductive TiO2 barrier layer on the reflecting plane of a Si prism is demonstrated to address this challenge. In situ ATR-SEIRAS measurement on a Au film electrode with the Si/TiO2 composite IRE in 1 M NaOH reveals reversible global spectral features without spectral distortion at 1000-1300 cm-1, in stark contrast to those obtained with a bare Si window. By applying this structured ATR-SEIRAS, ethanol electrooxidation on a Pt/C catalyst in 1 and 5 M NaOH is explored, manifesting that such high pH values prevent the adsorption of as-formed acetate in the C2 pathway but not that of CO intermediate in the C1 pathway.

Chamomile: A Review of Its Traditional Uses, Chemical Constituents, Pharmacological Activities and Quality Control Studies.

Matricaria chamomilla L. (MC) and Chamaemelum nobile (L.) All. (CN) are two varieties of Chamomile. These herbs have been used for thousands of years in Greece, Rome and ancient Egypt. Chamomile has been used for the treatment of stomach problems, cramps, dermatitis, and minor infections. The purpose of this study was to introduce the botanical characteristics and geographical distribution, traditional uses, chemical constituents, pharmacological activities, toxicity studies and quality control studies, and lay a theoretical foundation for the rational development and utilization of chamomile. This review powered that chemical constituents include flavonoids, coumarins, volatile oils, terpenes, organic acids, polysaccharides, and others. These compounds possess anticancer, anti-infective, anti-inflammatory, antithrombotic, antioxidant, hypolipidaemic, hypoglycaemic, antihypertensive, antidepressant, neuroprotective activities, among others. Chamomile is a widely used herb in traditional medicine. It brings great economic value due to its numerous pharmacological effects and traditional uses. However, more toxicity tests should be carried out to confirm its safety. There is need for further research to provide concrete scientific evidence and validate its medicinal properties.

Graphene-Nanorod Enhanced Quasi-Van Der Waals Epitaxy for High Indium Composition Nitride Films.

The nitride films with high indium (In) composition play a crucial role in the fabrication of In-rich InGaN-based optoelectronic devices. However, a major limitation is In incorporation requiring a low temperature during growth at the expense of nitride dissociation. Here, to overcome this limitation, a strain-modulated growth method, namely the graphene (Gr)-nanorod (NR) enhanced quasi-van der Waals epitaxy, is proposed to increase the In composition in InGaN alloy. The lattice transparency of Gr enables constraint of in-plane orientation of nitride film and epitaxial relationships at the heterointerface. The Gr interlayer together with NRs buffer layer substantially reduces the stress of the GaN film by 74.4%, from 0.9 to 0.23 GPa, and thus increases the In incorporation by 30.7%. The first principles calculations confirm that the release of strain accounts for the dramatic improvement. The photoluminescence peak of multiple quantum wells shifts from 461 to 497 nm and the functionally small-sized cyan light-emitting diodes of 7 × 9 mil2 are demonstrated. These findings provide an efficient approach for the growth of In-rich InGaN film and extend the applications of nitrides in advanced optoelectronic, photovoltaic, and thermoelectric devices.

DNA barcoding and species delimitation of butterflies (Lepidoptera) from Nigeria.

Accurate identification of species is a prerequisite for successful biodiversity management and further genetic studies. Species identification techniques often require both morphological diagnostics and molecular tools, such as DNA barcoding, for correct identification. In particular, the use of the subunit I of the mitochondrial cytochrome c oxidase (COI) gene for DNA barcoding has proven useful in species identification for insects. However, to date, no studies have been carried out on the DNA barcoding of Nigerian butterflies. We evaluated the utility of DNA barcoding applied for the first time to 735 butterfly specimens from southern Nigeria. In total, 699 DNA barcodes, resulting in a record of 116 species belonging to 57 genera, were generated. Our study sample comprised 807 DNA barcodes based on sequences generated from our current study and 108 others retrieved from BOLD. Different molecular analyses, including genetic distance-based evaluation (Neighbor-Joining, Maximum Likelihood and Bayesian trees) and species delimitation tests (TaxonDNA, Automated Barcode Gap Discovery, General Mixed Yule-Coalescent, and Bayesian Poisson Tree Processes) were performed to accurately identify and delineate species. The genetic distance-based analyses resulted in 163 well-separated clusters consisting of 147 described and 16 unidentified species. Our findings indicate that about 90.20% of the butterfly species were explicitly discriminated using DNA barcodes. Also, our field collections reported the first country records of ten butterfly species-Acraea serena, Amauris cf. dannfelti, Aterica galena extensa, Axione tjoane rubescens, Charaxes galleyanus, Papilio lormieri lormeri, Pentila alba, Precis actia, Precis tugela, and Tagiades flesus. Further, DNA barcodes revealed a high mitochondrial intraspecific divergence of more than 3% in Bicyclus vulgaris vulgaris and Colotis evagore. Furthermore, our result revealed an overall high haplotype (gene) diversity (0.9764), suggesting that DNA barcoding can provide information at a population level for Nigerian butterflies. The present study confirms the efficiency of DNA barcoding for identifying butterflies from Nigeria. To gain a better understanding of regional variation in DNA barcodes of this biogeographically complex area, future work should expand the DNA barcode reference library to include all butterfly species from Nigeria as well as surrounding countries. Also, further studies, involving relevant genetic and eco-morphological datasets, are required to understand processes governing mitochondrial intraspecific divergences reported in some species complexes.

Horizontal GaN nanowires grown on Si (111) substrate: the effect of catalyst migration and coalescence.

Here, we demonstrate the growth of horizontal GaN nanowires (NWs) on silicon (111) by a surface-directed vapor-liquid-solid growth. The influence of the Au/Ni catalysts migration and coalescence on the growth of the NWs has been systematically studied. 2D root-like branched NWs were gown spontaneously through catalyst migration. Furthermore, a novel phenomenon that a catalyst particle is embedded in a horizontal NW was observed and attributed the destruction of growth steady state due to the catalysts coalescence. The transmission electron microscopy and photoluminescence, cathodoluminescence measurement demonstrated that the horizontal NWs exhibit single crystalline structures and good optical properties. Our work sheds light on the horizontal NWs growth and should facilitate the development of highly integrated III-V nanodevices on silicon.

Fast Growth of Strain-Free AlN on Graphene-Buffered Sapphire.

We study the roles of graphene acting as a buffer layer for growth of an AlN film on a sapphire substrate. Graphene can reduce the density of AlN nuclei but increase the growth rate for an individual nucleus at the initial growth stage. This can lead to the reduction of threading dislocations evolved at the coalescence boundaries. The graphene interlayer also weakens the interaction between AlN and sapphire and accommodates their large mismatch in the lattice and thermal expansion coefficients; thus, the compressive strain in AlN and the tensile strain in sapphire are largely relaxed. The effective relaxation of strain further leads to a low density of defects in the AlN films. These findings reveal the roles of graphene in III-nitride growth and offer valuable insights into the efficient applications of graphene in the light-emitting diode industry.

Diversity and human perceptions of bees (Hymenoptera: Apoidea) in Southeast Asian megacities.

Urbanization requires the conversion of natural land cover to cover with human-constructed elements and is considered a major threat to biodiversity. Bee populations, globally, are under threat; however, the effect of rapid urban expansion in Southeast Asia on bee diversity has not been investigated. Given the pressing issues of bee conservation and urbanization in Southeast Asia, coupled with complex factors surrounding human-bee coexistence, we investigated bee diversity and human perceptions of bees in four megacities. We sampled bees and conducted questionnaires at three different site types in each megacity: a botanical garden, central business district, and peripheral suburban areas. Overall, the mean species richness and abundance of bees were significantly higher in peripheral suburban areas than central business districts; however, there were no significant differences in the mean species richness and abundance between botanical gardens and peripheral suburban areas or botanical gardens and central business districts. Urban residents were unlikely to have seen bees but agreed that bees have a right to exist in their natural environment. Residents who did notice and interact with bees, even though being stung, were more likely to have positive opinions towards the presence of bees in cities.

Controlled NiOx Defect Engineering to Harnessing Redox Reactions in Perovskite Photovoltaic Cells via Atomic Layer Deposition.

Albeit the undesirable attributes of NiOx, such as low conductivity, unmanageable defects, and redox reactions occurring at the perovskite/NiOx interface, which impede the progress in inverted perovskite solar cells (i-PSCs), it is the most favorable choice of technology for industrialization of PSCs. In this study, we propose a novel Ni vacancy defect modulate approach to leverage the conformal growth and surface self-limiting reaction characteristics of the atomic layer deposition (ALD)-fabricated NiOx by varying the O2 plasma injection time (tOE) to induce self-doping. Consequently, NiOx thin films with enhanced conductivity, an appropriate Ni3+/Ni2+ ratio, stable surface states, and ultrathinness are realized as hole-transporting layers (HTLs) in p-i-n PSCs. As a result of these improvements, ALD-NiOx-based devices exhibit the highest power conversion efficiency (PCE) of 19.86% and a fill factor (FF) of 81.86%. Notably, the optimal interfacial defects effectively suppressed the severe reaction between the perovskite and NiOx. This suppression is evidenced by the lowest decay rate observed in a harsh environment, lasting for 500 consecutive hours. The proposed approach introduces the possibility of a hierarchical distribution of defects and offers feasibility for the fabrication of large-area, uniform, and high-quality films.

Geological events play a larger role than Pleistocene climatic fluctuations in driving the genetic structure of Quasipaa boulengeri (Anura: Dicroglossidae).

Paleoclimatic and paleogeological events have been identified as being the two main drivers of genetic structuring in extant organisms. We used a montane stream-dwelling frog, Quasipaa boulengeri, to explore the relative roles played by these drivers on species in southern China, a region needing thorough studies. We detected four major matrilines, and no broadly distributed haplotypes occurred. The complex orogenesis of south-western China drove matrilineal divergence in Q. boulengeri into highly structured geographical units. These matrilines subsequently persisted in situ with stable populations rather than undergoing expansions during glacial cycling. The unification of the upper and middle Yangtze River in the Three Gorges mountain region mediated downstream colonization of this frog. Analyses identified geological events as playing a larger role than climatic fluctuations in driving the population history of Q. boulengeri. Nuclear allele analyses indicated gene flow; this maintained genetic cohesion of the species. South-eastern Sichuan Basin was identified as the area of secondary contact for several matrilines, and this area deserves further study and special protection.

Fission cross-section measurement for Xe135m and Xe135g in U238 reaction induced by 14MeV D-T neutrons.

In this work, the independent fission cross-sections of U(n,f)238Xe135g and U(n,f)238Xe135m reactions induced by neutrons with the energies of 14.1 MeV, 14.5 MeV, and 14.7 MeV were measured by activation methods. The neutrons from T(d,n)He4 were used in the experiments and their energies were determined by the ratio of Zr(n,2n)90Zr89 and Nb(n,2n)93Nb92m reaction cross-sections. Aluminum films were chosen as reference samples to measure the neutron fluence relative to the cross section of the Al(n,α)27Na24 reaction. The effect of self-absorption, geometry, and cascade coincidence were also considered during the data analysis. Besides, the increase in the daughter nuclide yield due to the decay of the parent nuclides in the same decay chain was deducted. As a result, the independent fission cross-sections of the U(n,f)238Xe135g reaction are 2.54 ± 0.14 mb, 3.05 ± 0.19 mb and 2.94 ± 0.19 mb, while the cross-sections of U(n,f)238Xe135m reaction are 2.11 ± 0.16 mb, 2.47 ± 0.18 mb and 2.34 ± 0.21 mb for 14.1 MeV, 14.5 MeV and 14.7 MeV neutrons, respectively. This work provides experimental data for the database of nuclear fission reactions.

ß-Escin: An Updated Review of Its Analysis, Pharmacology, Pharmacokinetics, and Toxicity.

[Formula: see text]-Escin is an oleanane-type pentacyclic triterpenoid saponin extracted from the seeds of Aesculus hippocastanum (AH), which is more widely distributed. [Formula: see text]-Escin sodium has been approved by the American FDA for clinical usage. This paper is intended to summarize an updated and comprehensive review of the pharmacological activities, pharmacokinetic properties, toxicity, and analytical methods of [Formula: see text]-escin. Studies have shown that [Formula: see text]-escin has significant antitumor, antiviral, anti-inflammatory, and other activities alongside less adverse effects and higher safety than other compounds. The review shows that the pharmacological effects of [Formula: see text]-escin involve mechanisms such as ATM/[Formula: see text]H2AX, RhoA/Rock, GSK-3[Formula: see text]/[Formula: see text]-Catenin, HER2/HER3/Akt, and PI3K/Akt signaling pathways, and Cyclin A, p21[Formula: see text], survivin, Bcl-2, Mcl-1, Caspases, TGF-[Formula: see text], MMPs, and TNF-[Formula: see text] among other inflammatory factors. [Formula: see text]-Escin has significant cytotoxicity; the use of the chitosan/xanthan gum-based polyelectrolyte complexes PA1 and PC-11 to modify it not only to reduces its toxicity, but also improves its drug efficacy. Because of this, these compounds may become a new research hotspot. [Formula: see text]-Escin in vivo metabolism can be converted by the CYP1A2 enzyme in the intestinal flora to produce [Formula: see text]-escin, deacylated, deglycosylated, and 21[Formula: see text]-[Formula: see text]-crotonoyl-protoescin, and the binding rate of the plasma proteins is higher than 90%. These are mainly metabolized by the liver, kidneys, and other organs, and excreted in the form of urine and feces. The number of reports on the specific mediators of the metabolism of [Formula: see text]-escin and their mechanisms and metabolites is relatively small; furthermore, the results are vague. Therefore, a complete and in-depth exploration of the pharmacokinetic characteristics of [Formula: see text]-escin is needed to provide a more complete and effective theoretical reference for the study of its pharmacodynamic activity.

Bryum billardieri Schwaegr. against EV71 infection: in vitro and in vivo antiviral effects, identification of molecular mechanisms and active monomers.

Enterovirus 71 (EV71) commonly causes symptoms such as hand, foot, and mouth disease (HFMD) in infants and children and may lead to neurological disease and even death in severe cases. Appropriate vaccines for the prevention of HFMD are available in the clinic; however, they present different and serious adverse effects that cannot guarantee compliance and efficacy. The purpose of this study was to analyze the potential mechanism of Bryum billardieri Schwaegr. (BBS) against EV71 and analyze its potential active components. A previous in vitro antiviral assay was used to determine the best extraction method for the active site of BBS against EV71, and the results showed that the antiviral activity of BBS was more pronounced in the fraction that was extracted by aqueous extraction and alcoholic precipitation and then obtained by purification on a silica gel column (dichloromethane:methanol = 0:100). In addition, the therapeutic effects of BBS on EV71-infected mice were further investigated by in vivo pharmacological experiments. BBS reduced the lung index, viral titer, and degree of EV71-induced lung, brain, and skeletal muscle damage. The mechanism of anti-EV71 activity of BBS was also investigated by using ELISA and qRT-PCR, and it was found that BBS exerted its action mainly by regulating the expression of TLR3, TLR4, TNF-α, IL-2, and IFN-γ by modulating the activation of NF-κB and JAK2/STAT1 signaling pathways. Finally, the chemical structures of the active monomers in BBS were determined by using UPLC-MS and NMR techniques. The study revealed that one of the monomers on which BBS exerts its antiviral activity is saponarin. In conclusion, the results of this study suggest that BBS is considered a natural anti-EV71 product with enormous potential, and saponarin would be its non-negligible active monomer.

Population structure and evolutionary history of the greater cane rat (Thryonomys swinderianus) from the Guinean Forests of West Africa.

Grasscutter (Thryonomys swinderianus) is a large-body old world rodent found in sub-Saharan Africa. The body size and the unique taste of the meat of this major crop pest have made it a target of intense hunting and a potential consideration as a micro-livestock. However, there is insufficient knowledge on the genetic diversity of its populations across African Guinean forests. Herein, we investigated the genetic diversity, population structures and evolutionary history of seven Nigerian wild grasscutter populations together with individuals from Cameroon, Republic of Benin, and Ghana, using five mitochondrial fragments, including D-loop and cytochrome b (CYTB). D-loop haplotype diversity ranged from 0.571 (± 0.149) in Republic of Benin to 0.921 (± 0.013) in Ghana. Within Nigeria, the haplotype diversity ranged from 0.659 (± 0.059) in Cross River to 0.837 (± 0.075) in Ondo subpopulation. The fixation index (FST), haplotype frequency distribution and analysis of molecular variance revealed varying levels of population structures across populations. No significant signature of population contraction was detected in the grasscutter populations. Evolutionary analyses of CYTB suggests that South African population might have diverged from other populations about 6.1 (2.6-10.18, 95% CI) MYA. Taken together, this study reveals the population status and evolutionary history of grasscutter populations in the region.

Comparing three quantification methods on N/Si ratio analysis using electron energy loss spectroscopy (EELS).

Precision elemental analysis by EELS at a nano-meter scale is a desirable goal for industrial application, as well as basic scientific research on advanced material analysis. However, sample thickness variation leads to a systematic error in element quantification due to electron plural scattering events and prevents it to be a useful quantitative analytic method. In this paper, we compared three methods to minimize thickness effect: Fourier-log deconvolution, Jump ratio, and Si K-edge by quantifying the N/Si ratio versus different thickness on a standard Si3N4 crystal sample. The results indicated that Jump ratio method exceeded other two methods owing to its higher accuracy, short data acquisition time as well as minimum requirement for spectroscopy instrument. The jump ratio method was applied to calculate N/Si ratio in storage nitride layer of 3D NAND trench wafer and blanket wafer, both illustrated that the jump ratio method successfully corrected the thickness effect on EELS composition quantification and largely reduced the relative error compared with the non-corrected result.

Preparation and pharmacokinetics in vivo of linarin solid dispersion and liposome.

Objective: The current investigation aimed to determine the appropriate dosage form by comparing solid dispersion and liposome to achieve the purpose of improving the solubility and bioavailability of linarin. Methods: Linarin solid dispersion (LSD) and linarin liposome (LL) were developed via the solvent method and the thin film hydration method respectively. The Transwell chamber model of Caco-2 cells was established to evaluate the absorption of drug. The pharmacokinetics of linarin, LSD and LL in rats after ig administration were carried out by high performance liquid chromatography (HPLC) method. Results: The solubility of LSD and LL was severally 3.29 times and 3.09 times than that of linarin. The permeation coefficients of LSD and LL were greater than 10-6, indicating that the absorption of LSD and LL were both better than linarin. The bioavailability of the LSD was 3.363 times higher than that of linarin, and the bioavailability of LL was 0.9886 times higher than that of linarin. Conclusion: The linarin was more suitable for making solid dispersion to enhance its solubility and bioavailability.

Complete mitochondrial genome sequence for the Thrips hawaiiensis (Thysanoptera: Thripidae).

Thrips hawaiiensis (Morgan) (Thysanoptera: Thripidae) is a common Thysanoptera insect widely distributed in Asia and the Pacific, it damages various plants. In this study the complete mitochondrial genome of T. hawaiiensis was sequenced and characterized by using next-generation sequencing technique. The total length of the complete genome is 15,357 bp and A + T content of 77.8% (GeneBank accession No. MW582621). The T. hawaiiensis mitochondrial genome consists of 13 protein-coding genes (PCGs), 2 ribosomal RNA genes, 22 transfer RNA genes (tRNAs) and 2 non-coding control regions (Dloop region). According to previous studies, only a few complete mitochondrial genomes from Order Thysanoptera have been reported. Thus, T. hawaiiensis complete mitochondrial genome sequence reported will provide molecular information for mitochondrial genome research on Thysanoptera.

A method of using Si L-edge for O/Si and N/Si quantitative ratio analysis by electron energy loss spectroscopy (EELS).

In EELS core loss excitation, inverse jump ratio is defined as a ratio between intensity of a pre-core-loss-edge and a signal of the core loss excitation after background subtraction. A linear relationship between inverse jump ratio of Si L-edge and O/Si and N/Si intensity ratio is found for electron energy loss spectroscopy (EELS) analysis. This relationship is used to analyze O/Si and N/Si atomic ratio to quantify the elemental distribution in SiON films and the result is compared with XPS analysis on the same SiON films. The method is applied to blanket wafer elemental analysis and can be used for flash memory structure (3D NAND) to obtain atomic ratios of N/Si and O/Si for tunnel oxide at sub-nanometer scale.

Band gap measurement by nano-beam STEM with small off-axis angle transmission electron energy loss spectroscopy (TEELS).

An energy band gap measurement method based on nano-beam STEM with small off-axis angle valence band transmission electron energy loss spectroscopy (TEELS) is reported. The effect of multiple scattering event is removed by self-convolution method to obtain a single scattering loss function and a dielectric function is calculated from the single scattering valence band energy loss function through Kramers-Kronig (K-K) analysis. Optical band gaps are extracted from energy loss spectra and the imaginary part of the dielectric functions for crystalline and amorphous SiOx, SiNx, and SiON through linear fitting of on-set regions yielding results that are independent of sample thickness. The TEELS band gap data are consistent with those obtained from reflection electron energy loss spectroscopy (REELS) measurements.

Salvia plebeia R. Br. polysaccharides (SPP) against RSV (respiratory syncytial virus) infection: Antiviral effect and mechanisms of action.

OBJECTIVE: To investigate the antiviral effect of Salvia plebeia R. Br. polysaccharides (SPP) against RSV and underlying mechanisms. METHODS: SPP was extracted via alcohol-precipitation method and extract was separated into various fractions using ultrafiltration method. The polysaccharide content was determined using UV-Vis. Antiviral effect of SPP and fractions was measured using MTT method and Reed-Muench method. Sixty Balb/c mice were randomly divided into 6 groups, and received either Ribavirin or SPP. Their body weight and food intake were recorded every day throughout the experiment period. The lung index inhibition ratio and pulmonary virus titer were determined followed by the histological analysis of lungs. Furthermore, time-of-addition and effective stage analysis were carried out to determine the mechanism of action. The TLR-3 and TLR-4 levels in the lungs were determined using qRT-PCR. The levels of IFN-γ, IL-2 and TNF-α in serum were determined using ELISA. RESULTS: The SPP content is 4.396%. SPP has shown a good anti-RSV effect both in vitro (TI = 123.041) and in vivo models. The antiviral activity of fractions with molecular weight ≥ 10,000 is found to possess more potent antiviral activity than other fractions. SPP inhibits the RSV proliferation and reduces the lung lesions induced by RSV. The mechanism of action involves the inhibition of TLR-3 and TLR-4 in lungs, up-regulation of IFN-γ and IL-2, and down-regulation of TNF-α in serum. It is also shown to improve the body's immune function. CONCLUSION: SPP has a potential to treat diseases caused by RSV.