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The enigmatic ultraviolet (UV) extinction bump at 2175  |$\, {\rm \mathring{\rm A}}$|⁠ , the strongest spectroscopic absorption feature superimposed on the interstellar extinction curve, has recently been detected at the cosmic dawn by the JWST in JADES-GS-z6-0, a distant galaxy at redshift |$z\approx 6.71$|⁠ , corresponding to a cosmic age of just 800 million years after the big bang. Although small graphite grains have historically long been suggested as the carrier of the 2175  |$\, {\rm \mathring{\rm A}}$| extinction bump and graphite grains are expected to have already been pervasive in the early Universe, in this work we demonstrate that small graphite grains are not responsible for the UV extinction bump seen at the cosmic dawn in JADES-GS-z6-0, as the extinction bump arising from small graphite grains is too broad and peaks at wavelengths that are too short to be consistent with what is seen in JADES-GS-z6-0. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbon (PAH) molecules have long been suggested to be present in the interstellar medium (ISM). Nevertheless, despite their expected ubiquity and sustained searching efforts, identifying specific interstellar PAH molecules from their infrared (IR) spectroscopy has so far been unsuccessful. However, due to its unprecedented sensitivity, the advent of the JWST may change this. Meanwhile, recent years have witnessed breakthroughs in detecting specific PAH molecules (e.g. indene, cyanoindene, and cyanonaphthalene) through their rotational lines in the radio frequencies. As JWST holds great promise for identifying specific PAH molecules in the ISM based on their vibrational spectra in the IR, in this work, we model the vibrational excitation of indene, a molecule composed of a six-membered benzene ring fused with a five-membered cyclopentene ring, and calculate its IR emission spectra for a number of representative astrophysical regions. This will facilitate JWST to search for and identify indene in space through its vibrational bands and to quantitatively determine or place an upper limit on its abundance. [ABSTRACT FROM AUTHOR]

N-Benzenesulfonyl amino acid esters have drawn much attention due to their pharmacological and biological activity. Herein, a facile and effective one-pot approach to N-benzenesulfonyl amino acid esters has been developed, and 16 compounds have been obtained in excellent yields (90–95%) in a short time (9–14 min) using 4-bromobenzenethiol and amino acid esters as starting materials. Significantly, methyl 2-(4-bromoben-zene-sulfon-amido)acetate (3a) could enhance the proline content of soybean in response to excess cadmium in a way similar to the plant hormone abscisic acid. [ABSTRACT FROM AUTHOR]

The exact nature of the 2175 |$\mathring{\rm A}$| extinction bump, the strongest spectroscopic absorption feature superimposed on the interstellar extinction curve, remains unknown ever since its discovery in 1965. Popular candidate carriers for the extinction bump include nano-sized graphitic grains and polycyclic aromatic hydrocarbon (PAH) molecules. To quantitatively evaluate PAHs as a possible carrier, we perform quantum chemical computations for the electronic transitions of 30 compact, pericondensed PAH molecules and their cations as well as anions with a wide range of sizes from 16 to 96 C atoms, and a mean size of 43 C atoms. It is found that a mixture of such PAHs, which individually exhibit sharp absorption features, show a smooth and broad absorption band that resembles the 2175 |$\mathring{\rm A}$| interstellar extinction bump. Arising from π* ← π transitions, the width and intensity of the absorption bump for otherwise randomly selected and uniformly weighted PAH mixtures, do not vary much with PAH sizes and charge states, whereas the position somewhat shifts to longer wavelengths as PAH size increases. While the computed bump position, with the computational uncertainty taken into account, appears to agree with that of the interstellar extinction bump, the computed width is considerably broader than the interstellar bump if the molecules are uniformly weighted. It appears that, to account for the observed bump width, one has to resort to PAH species of specific sizes and structures. [ABSTRACT FROM AUTHOR]

The most striking characteristics of the mysterious 2175 |$\mathring{\rm A}$| extinction bump, the strongest spectroscopic absorption feature seen on the interstellar extinction curve, are the invariant central wavelength and variable bandwidth: its peak position at 2175 |$\mathring{\rm A}$| is remarkably constant, while its bandwidth varies from one line of sight to another. However, recent studies of the lines of sight towards a number of Herbig Ae/Be stars have revealed that the extinction bump exhibits substantial shifts from the canonical wavelength of 2175 |$\mathring{\rm A}$|⁠. In this work, we revisit these lines of sight and take a physical approach to determine the ultraviolet (UV) extinction curve for each line of sight. It is found that the wavelengths of the derived UV extinction bumps are around 2200 |$\mathring{\rm A}$| and the scatters are considerably smaller than those of the previous study based on the same set of Herbig Ae/Be stars, consistent with the conventional wisdom of a stable bump position. Nevertheless, the scatters are still appreciably larger than those associated with the nominal bump position of 2175 |$\mathring{\rm A}$|⁠. This is discussed in the context that Herbig Ae/Be stars are not well suited for interstellar extinction studies. [ABSTRACT FROM AUTHOR]

A novel characterization method is introduced to measure Seebeck coefficients on individual Si nanowires (Si NWs). By using conductive atomic force microscopy with slight modifications, without any need of microfabricated devices, the Seebeck coefficients can be conveniently measured on individual Si NWs inside a large-sized vertical array in addition to the measurements on bulk substrates. The results show that the Seebeck coefficients of Si NWs are much larger than their bulk counterparts over a wide temperature range. The temperature dependence of the Seebeck coefficients of Si NWs is found to be entirely different from that of bulk Si, yet both of them agree well with the results obtained by a macroscopic method. Particularly, with this method, the Seebeck coefficients can be easily characterized on Si NWs with varied morphology, size, or doping. As an example, the Seebeck coefficients are measured on Si NWs with different lengths, and it is found that the Seebeck coefficients decrease obviously as the nanowire length increases for all measurement temperatures but the difference becomes smaller at higher temperatures. Overall, this study provides a simple but effective novel method to measure the Seebeck coefficients on individual Si NWs, which has unique advantages on exploring the size or other parameter dependence or revealing the dominant factors in thermoelectric property studies on single nanostructures. [ABSTRACT FROM AUTHOR]

Background: The World Health Organization has reported that the treatment success rate of multi-drug resistance tuberculosis is approximately 57% globally. Although new drugs such as bedaquiline and linezolid is likely improve the treatment outcome, there are other factors associated with unsuccessful treatment outcome. The factors associated with unsuccessful treatment outcomes have been widely examined, but only a few studies have developed prediction models. We aimed to develop and validate a simple clinical prediction model for unsuccessful treatment outcomes in patients with multi-drug resistance pulmonary tuberculosis (MDR-PTB). Methods: This retrospective cohort study was performed between January 2017 and December 2019 at a special hospital in Xi'an, China. A total of 446 patients with MDR-PTB were included. Least absolute shrinkage and selection operator (LASSO) regression and multivariate logistic regression were used to select prognostic factors for unsuccessful treatment outcomes. A nomogram was built based on four prognostic factors. Internal validation and leave-one-out cross-validation was used to assess the model. Results: Of the 446 patients with MDR-PTB, 32.9% (147/446) cases had unsuccessful treatment outcomes, and 67.1% had successful outcomes. After LASSO regression and multivariate logistic analyses, no health education, advanced age, being male, and larger extent lung involvement were identified as prognostic factors. These four prognostic factors were used to build the prediction nomograms. The area under the curve of the model was 0.757 (95%CI 0.711 to 0.804), and the concordance index (C-index) was 0.75. For the bootstrap sampling validation, the corrected C-index was 0.747. In the leave-one-out cross-validation, the C-index was 0.765. The slope of the calibration curve was 0.968, which was approximately 1.0. This indicated that the model was accurate in predicting unsuccessful treatment outcomes. Conclusions: We built a predictive model and established a nomogram for unsuccessful treatment outcomes of multi-drug resistance pulmonary tuberculosis based on baseline characteristics. This predictive model showed good performance and could be used as a tool by clinicians to predict who among their patients will have an unsuccessful treatment outcome. [ABSTRACT FROM AUTHOR]

Patients with kidney disease are at increased risk of adverse mortality events. Numerous studies have demonstrated the positive association of high-sensitivity cardiac troponin T (hs-cTnT) and I (hs-cTnI) with all-cause and cardiovascular (CV) mortality in patients with kidney disease; however, the dose–response meta-analysis has not been reported. We therefore performed this study to evaluate the dose–response associations of hs-cTn with risk of all-cause and CV mortality to improve risk stratification. We searched three databases (PubMed, Embase and Web of Science) to identify relevant prospective cohort studies published up to 12 January 2021. Random-effects models were used to summarize relative risks (RRs) and 95% confidence intervals (CIs) of all-cause and CV mortality. Restricted cubic splines were used to fit the dose–response associations. For each 10 ng/l increase in hs-cTnT and hs-cTnI, the risk increased by 14% (RR = 1.14, 95% CI, 1.10–1.18) and 19% (RR = 1.19, 95% CI, 1.09–1.31) for all-cause mortality, 25% (RR = 1.25, 95% CI, 1.13–1.38) and 19% (RR = 1.19, 95% CI, 1.10–1.29) for CV mortality. A linear trend was found between hs-cTnT and all-cause mortality, whereas a non-linear trend was found in hs-cTnI. Additionally, both hs-cTnT and hs-cTnI were shown to have linear trends with CV mortality. Our meta-analysis suggests that hs-cTn had high sensitivity in predicting mortality events. All dose–response trends were rising rather than falling, conferring that any increase in the levels of hs-cTn may possibly predict a death prognosis among chronic kidney disease patients. [ABSTRACT FROM AUTHOR]

Time-resolved optical spin orientation spectroscopy was employed to investigate the temperaturedependent electron spin injection in In0.1Ga0.9As quantum well (QW) and In0.5Ga0.5As quantum dots (QDs) tunnel-coupled nanostructures with 4, 6, and 8 nm-thick GaAs barriers. The fast picosecond-ranged spin injection from QW to QD excited states (ES) was observed to speed up with temperature, as induced by pronounced longitudinal-optical (LO)-phonon-involved multiple scattering process, which contributes to a thermally stable and almost fully spin-conserving injection within 5-180 K. The LO-phonon coupling was also found to cause accelerated electron spin relaxation of QD ES at elevated temperature, mainly via hyperfine interaction with random nuclear field. [ABSTRACT FROM AUTHOR]

This study investigated the antipathogenic activity and probiotic potential of indigenous lactic acid bacteria (LAB) isolated from Chinese homemade pickles. In total, 27 samples were collected from different sites in China. Fifty-nine yielded pure colonies were identified by 16S rRNA gene sequencing as LAB and were initially evaluated for the antibacterial activity in vitro. Initial screening yielded Lactobacillus plantarum GS083, GS086, and GS090, which showed a broad-spectrum antibacterial activity against food-borne pathogens, especially multidrug-resistant pathogens. Meanwhile, organic acids were mainly responsible for the antimicrobial activity of the LAB strains, and the most abundant of these was lactic acid (19.32 ± 0.95 to 24.79 ± 0.40 g/l). Additionally, three L. plantarum strains demonstrated several basic probiotic characteristics including cell surface hydrophobicity, autoaggregation, and survival under gastrointestinal (GI) tract conditions. The safety of these isolates was also evaluated based on their antibiotic susceptibility, hemolytic risk, bile salt hydrolase activity, and existence of virulence or antibiotic resistance genes. All strains were safe at both the genomic and phenotypic levels. Therefore, L. plantarum GS083, GS086, and GS090 are fairly promising probiotic candidates and may be favorable for use as preservatives in the food industry. [ABSTRACT FROM AUTHOR]

Phytase has long been used to decrease the inorganic phosphorus (Pi) input in poultry diet. The current study was conducted to investigate the effects of Pi supplementation on laying performance, egg quality and phosphate–calcium metabolism in Hy-Line Brown laying hens fed phytase. Layers (n = 504, 29 weeks old) were randomly assigned to seven treatments with six replicates of 12 birds. The corn–soybean meal-based diet contained 0.12% non-phytate phosphorus (nPP), 3.8% calcium, 2415 IU/kg vitamin D3 and 2000 FTU/kg phytase. Inorganic phosphorus (in the form of mono-dicalcium phosphate) was added into the basal diet to construct seven experimental diets; the final dietary nPP levels were 0.12%, 0.17%, 0.22%, 0.27%, 0.32%, 0.37% and 0.42%. The feeding trial lasted 12 weeks (hens from 29 to 40 weeks of age). Laying performance (housed laying rate, egg weight, egg mass, daily feed intake and feed conversion ratio) was weekly calculated. Egg quality (egg shape index, shell strength, shell thickness, albumen height, yolk colour and Haugh units), serum parameters (calcium, phosphorus, parathyroid hormone, calcitonin and 1,25-dihydroxyvitamin D), tibia quality (breaking strength, and calcium, phosphorus and ash contents), intestinal gene expression (type IIb sodium-dependent phosphate cotransporter, NaPi-IIb) and phosphorus excretion were determined at the end of the trial. No differences were observed on laying performance, egg quality, serum parameters and tibia quality. Hens fed 0.17% nPP had increased (P < 0.01) duodenum NaPi-IIb expression compared to all other treatments. Phosphorus excretion linearly increased with an increase in dietary nPP (phosphorus excretion = 1.7916 × nPP + 0.2157; R2 = 0.9609, P = 0.001). In conclusion, corn–soybean meal-based diets containing 0.12% nPP, 3.8% calcium, 2415 IU/kg vitamin D3 and 2000 FTU/kg phytase would meet the requirements for egg production in Hy-Line Brown laying hens (29 to 40 weeks of age). [ABSTRACT FROM AUTHOR]

The development of digestive organs and the establishment of gut microbiota in pullets play an important role throughout life. This study was conducted to investigate the effects of Bacillus subtilis (BS) on growth performance, intestinal function and gut microbiota in pullets from 0 to 6 weeks of age. Hy-line Brown laying hens (1-day-old, n = 504) were randomly allotted into four diets with a 2 × 2 factorial design: (1) basal diet group (control); (2) antibiotics group (AGP), the basal diet supplemented with 20 mg/kg Bacitracin Zinc and 4 mg/kg Colistin Sulphate; (3) BS group, the basal diet supplemented with 500 mg/kg BS and (4) mixed group, the basal diet supplemented with both AGP and BS. As a result, when BS was considered the main effect, BS addition (1) reduced the feed conversion ratio at 4 to 6 weeks (P < 0.05); (2) decreased duodenal and jejunal crypt depth at 3 weeks; (3) increased the villus height : crypt depth (V : C) ratio in the duodenum at 3 weeks and jejunal villus height at 6 weeks and (4) increased sucrase mRNA expression in the duodenum at 3 weeks as well as the jejunum at 6 weeks, and jejunal maltase and aminopeptidase expression at 3 weeks. When AGP was considered the main effect, AGP supplementation (1) increased the V : C ratio in the ileum at 3 weeks of age; (2) increased sucrase mRNA expression in the duodenum at 3 weeks as well as the ileum at 6 weeks, and increased maltase expression in the ileum. The BS × AGP interaction was observed to affect average daily feed intake at 4 to 6 weeks, and duodenal sucrase and jejunal maltase expression at 3 weeks. Furthermore, dietary BS or AGP addition improved caecal microbial diversity at 3 weeks, and a BS × AGP interaction was observed (P < 0.05) for the Shannon and Simpson indexes. At the genus level, the relative abundance of Lactobacillus was found to be higher in the mixed group at 3 weeks and in the BS group at 6 weeks. Moreover, Anaerostipes, Dehalobacterium and Oscillospira were also found to be dominant genera in pullets with dietary BS addition. In conclusion, BS could improve intestinal morphology and change digestive enzyme relative expression and caecum microbiota, thereby increasing the efficiency of nutrient utilization. Our findings suggested that BS might have more beneficial effects than AGP in the study, which would provide theoretical evidence and new insight into BS application in layer pullets. [ABSTRACT FROM AUTHOR]

The reaction of digallane [(dpp-bian)Ga—Ga(dpp-bian)] (1) (dpp-bian is 1,2-bis[(2,6-di-isopropylphenyl)imino]acenaphthene dianion) with chromium or tungsten hexacarbonyl affords the complexes [(dpp-bian)Ga—Cr(CO)5] (2) and [(dpp-bian)Ga—W(CO)5] (3), respectively, containing the neutral radical [(dpp-bian)Ga:]. In both cases, temperature-dependent solvation of the gallium center was observed in a tetrahydrofuran solution. The recrystallization of compound 2 from pyridine gave the new complex [(dpp-bian)(Py)Ga—Cr(CO)5] (4). New compounds 2–4 were characterized by EPR and IR spectroscopy and elemental analysis. The molecular structures of complexes 2–4 were established by single-crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

In this paper, the influence of the dynamic stress concentration in a piezoelectric material with a non-circular hole subjected to a shear wave polarized so that its particle motion and direction of propagation are aligned in a horizontal plane (SH-wave) is investigated. The boundary conditions of the non-circular hole can be mapped into a unit circle by applying complex variables and conformal mapping. The analytical solution of the dynamic stress concentration factor is determined by the unknown mode coefficients obtained by using the boundary conditions. Numerical examples are presented to analyze the influence of the incident wave number, piezoelectric constant of the material, and eccentricity ratio of the hole on the distribution of the dynamic stress concentration factor. The analysis reveals that the distribution of the dynamic stress concentration factor on the incident direction of the SH-wave is significantly different from that on the other side. [ABSTRACT FROM AUTHOR]

Periodically ordered arrays of vertically aligned Si nanowires (Si NWs) are successfully fabricated by nanosphere lithography combined with metal-assisted chemical etching. By adjusting the etching time, both the nanowires' diameter and length can be well controlled. The conductive properties of such Si NWs and particularly their size dependence are investigated by conductive atomic force microscopy (CAFM) on individual nanowires. The results indicate that the conductance of Si NWs is greatly relevant to their diameter and length. Si NWs with smaller diameters and shorter lengths exhibit better conductive properties. Together with the I–V curve characterization, a possible mechanism is supposed with the viewpoint of size-dependent Schottky barrier height, which is further verified by the electrostatic force microscopy (EFM) measurements. This study also suggests that CAFM can act as an effective means to explore the size (or other parameters) dependence of conductive properties on individual nanostructures, which should be essential for both fabrication optimization and potential applications of nanostructures. [ABSTRACT FROM AUTHOR]

Some studies have shown that the excessive metabolic heat production is the primary cause for dead chicken embryos during late embryonic development. Increasing heat shock protein (HSP) expression and adjusting metabolism are important ways to maintain body homeostasis under heat stress. This study was conducted to investigate the effects of in ovo injection (IOI) of vitamin C (VC) at embryonic age 11th day (E11) on HSP and metabolic genes expression. A total of 320 breeder eggs were randomly divided into normal saline and VC injection groups. We detected plasma VC content and rectal temperature at chick's age 1st day, and the mRNA levels of HSP and metabolic genes in embryonic livers at E14, 16 and 18, analysed the promoter methylation levels of differentially expressed genes and predicted transcription factors at the promoter regions. The results showed that IOI of VC significantly increased plasma VC content and decreased rectal temperature (P < 0.05). In ovo injection of VC significantly increased heat shock protein 60 (HSP60) and pyruvate dehydrogenase kinase 4 (PDK4) genes expression at E16 and PDK4 and secreted frizzled related protein 1 (SFRP1) at E18 (P < 0.05). At E16, IOI of VC significantly decreased the methylation levels of total CpG sites and −336 CpG site in HSP60 promoter and −1137 CpG site in PDK4 promoter (P < 0.05). Potential binding sites for nuclear factor-1 were found around −389 and −336 CpG sites in HSP60 promoter and potential binding site for specificity protein 1 was found around −1137 CpG site in PDK4 promoter. Our results suggested that IOI of VC increased HSP60, PDK4 and SFRP1 genes expression at E16 and 18, which may be associated with the demethylation in gene promoters. Whether IOI of VC could improve hatchability needs to be further verified by setting uninjection group. [ABSTRACT FROM AUTHOR]

The magnetic properties of SiO2/Fe/SiO2 nanocomposite films are studied by magnetic force microscopy and vibrating sample magnetometer. The films were fabricated by alternately depositing SiO2, Fe, and SiO2 on Si substrates with magnetron sputtering followed by thermal annealing. It is found that the annealing atmosphere significantly influences the sample structure, composition, and magnetic properties. The samples annealed in forming gas show much better magnetic properties than those annealed in vacuum and in N2. The saturation magnetization can reach 200 emu/g, fairly close to the value of bulk Fe, and the coercivity can reach 400 Oe, much higher than 10 Oe of the bulk Fe. X-ray photoelectron spectroscopic depth profile measurement was carried out to study the mechanism of the strong influence of annealing atmosphere. For the samples annealed in forming gas, Fe nanoparticles are mildly oxidized, forming thin shells of Fe2O3 surrounding them, which is beneficial for maintaining the ferromagnetic behavior and enhancing the coercivity of nanoparticles. [ABSTRACT FROM AUTHOR]

Coherently strained GeSi/Si(001) islands were overgrown with a Si capping layer of different thicknesses at temperature 300 °C. The structures of the islands and the Si capping layer were investigated by high resolution transmission electron microscopy. The shapes of the embedded islands were well preserved, whereas planar defects were observed exactly over the islands in the capping layers. The strain energy in regions over the islands accumulated with increasing thickness of the Si capping layer, resulting in the formation of the planar defects. By means of a two-step deposition in which 20-nm-thick Si capping layer was first deposited at a low temperature of 300 °C followed by 70-nm-thick Si capping layer deposition at a high temperature of 640 °C, the defect-free Si capping layer with flat surface can be obtained. [ABSTRACT FROM AUTHOR]

The shape of the self-assembled GeSi/Si(001) islands changed from a dome to a pyramid bounded with {103} or {105} facets after initial Si capping at 640 °C. The strains in the islands with initial Si capping are investigated by Raman spectroscopy. Compared with those of the uncapped islands, both peaks of Ge-Ge and Ge-Si vibration modes in the capped islands show blueshifts, corresponding to the Ge content decrease and the compressive strain increase in the capped islands. The total strain energy in an island is found to increase remarkably after Si capping. After simple analysis, it is found that the surface energy change could not overwhelm this large strain energy increase, making the shape transition favorable. It implies that the strain energy in the substrate in association with an island formation as well as evolution should be considered in accounting for the resulting island shape changes after Si capping. [ABSTRACT FROM AUTHOR]

Hypoimmunity and numerous stresses are two major challenges in broiler industry. Nutrient intervention at the specific time of embryonic stage is a feasible way to improve animal performance. This study was conducted to investigate the possible effects of in ovo feeding (IOF) of vitamin C at embryonic age 15th day (E15) on growth performance, antioxidation and immune function of broilers. A total of 240 broiler fertile eggs were randomly divided into two groups (0 and 3 mg injected dose of vitamin C at E15), and new-hatched chicks from each treatment were randomly allocated into six replicates with 10 chicks per replicate after incubation. The results indicated that in ovo vitamin C injection improved the hatchability (P < 0.05) and increased immunoglobulin M (IgM) (at the broiler's age 1st day, D1), IgG and IgM concentrations (D21), as well as lysozyme activity (D21, P < 0.05) and total antioxidant capacity (D42, P < 0.01) in plasma of broilers. On D21, the splenic expression level of DNA methyltransferase 1 (DNMT1) was up-regulated in vitamin C (VC) group, whereas interleukin (IL)-6, interferon- γ , ten-eleven translocation protein 1 and thymine-DNA glycosylase were down-regulated (P < 0.05). On D42, in ovo vitamin C injection up-regulated splenic expression levels of DNMT1, DNA methyltransferase 3B (DNMT3B) and growth arrest and DNA-damage-inducible protein beta (P < 0.05), whereas down-regulated splenic expression levels of IL-6, tumour necrosis factor- α and methyl-CpG-binding domain protein 4 (P < 0.05). Our findings suggested that IOF of 3 mg vitamin C at E15 could improve, to some extent, the antioxidant activity and immune function in plasma, corresponding with the lower expression of pro-inflammatory cytokines in spleen. However, IOF of vitamin C leading to the changes in the expression of DNA methyltransferases and demethylases may suggest an increased trend of DNA methylation level in spleen and whether DNA methylation variation is associated with the lower expression of pro-inflammatory cytokines in spleen warrants future study. [ABSTRACT FROM AUTHOR]

Transplant density is an important factor which has impacts on rice growth and development in transplanted rice production system. Present study used three transplant densities in paddy field experiment and set as D1 (transplant spacing of 20 cm x 24 cm, about 2.085 hundred thousand hills for each hectare), D2 (transplant spacing of 20 cm x 20 cm, about 2.603 hundred thousand hills for each hectare) and D3 (transplant spacing of 20 cm x 16 cm, about 3.120 hundred thousand hills for each hectare). The results showed that high density (D3) not only reduced the net photosynthetic rate and LAI values at heading stage, but also decreased dry matter accumulation and transportation compared to D1 density. The highest yield was recorded in D1 density and the lowest yield was recorded in D3 density. Study also revealed that high density caused yield loss by decreasing the grain number and seed-setting rate. Furthermore, high density also increased chalk rice rate and chalkiness while reducing the amylose content. The activity of sucrose synthase (SS) in D3 was significantly lower than D1 and it might relate to the reduction of grain quality. [ABSTRACT FROM AUTHOR]

Observing different types of pores in aluminum alloy from A356 high-pressure die casting by X-ray computerized tomography and scanning electron microscopy, we found that equivalent spherical diameters of pores obeyed the 3-parameter lognormal distribution rather than the 2-parameter one. Statistically, the sphericity of most round gas pores with smooth inner surfaces consisting of oxide films was > 0.58, while the sphericity of shrinkage pores with unfractured dendrites was < 0.40. Sphericity range for the gas-shrinkage pores, composed of gas pores and shrinkage pores with long tails, was 0.40-0.58. Finite element analysis with simulation of the Von Mises stress distribution around the actual 3D pores among crack generation was performed. Tensile test simulation showed that cracks often originated from the shrinkage pores and the gas-shrinkage pores, rather than from the gas pores. This method also can be used to predict fracture strength of samples with pores. For our samples, results obtained using this method showed that simulated fracture strength was slightly higher than experimentally determined strength. [ABSTRACT FROM AUTHOR]

A triple-color photodetector with MSM structure based on the ZnO/MgZnO films was fabricated. There are three response peaks in the response spectrum for the triple-color photodetector, which response peaks are located at around 290, 320 and 360 nm, respectively. A further study on responsivity for the triple-photodetector is carried out. The rising velocity of cubic MgZnO (111) response peak is faster than hexagonal MgZnO (002) response peak, the different internal gain between the different crystal orientation is the main reason for the different of the response peaks between the two phases. This experiment would have a great significance for multiple-colors photodetectors field. [ABSTRACT FROM AUTHOR]

Using an ultrafast laser pulse as a substitution of continuous-wave laser to excite a magnetic film leads to high spin temperature and fast demagnetization, beneficial to the rapid and efficient photo-assisted magnetization (M) reversal. Here, ultrafast laser induced M reversal in perpendicular magnetic anisotropy L10 FePt films with different chemical ordering parameter (from S<0.6 to S>0.9) was investigated using magneto-optical Kerr effect (MOKE). It was found that the coercive field (Hc) without laser excitation increases from ∼0.8 to ∼4 kOe with increasing S, but Hc becomes smaller for enhanced laser fluence (F) and reaches an analogous small value of ∼0.2 kOe for F>12 mJ cm-2. Despite such a significant softening in films with high S, the laser induced M reversal rate is slightly less than 1 even for the applied field (H) much larger than 0.2 kOe. This reveals a small portion of spins are photo inactively pinned, as confirmed by magnetic force microscopy measurements. Such pinning sites may be reduced with improved chemical order and morphology. We also found an approximately inverse linear relation between the H and the corresponding threshold F to induce the M reversal in the film of high S, which can be described by an ultrafast thermal activated spin flip model. [ABSTRACT FROM AUTHOR]

A femtosecond (fs) pulsed laser was employed to drill microholes in TiC ceramic. The Morphologies of microholes drilled at different assisted gas pressures and laser feeding speeds were investigated. Chemical compositions and chemical bonds of laser treated debris and untreated specimen were analysed. The mechanism of interaction between the femtosecond laser and the TiC ceramic was discussed. The results indicated that the assisted gas pressure had a greater effect on the morphologies of microholes, compared with the feeding speed. The entrance diameter of microholes was smaller than the exit diameter. The entrance roundness was more perfect than the exit roundness, and the entrance roundness decreased slightly with increasing gas pressure and feeding speed. Higher feeding speed was unfavourable to the morphologies of microholes. Ti, C and O were detected in laser treated debris. X-ray photoelectron spectroscopy (XPS) investigation showed that the C-Ti bond was broken and Ti2 O3 and TiO2 were formed during drilling. [ABSTRACT FROM AUTHOR]

Starch is a product of photosynthetic activities in leaves. Wheat yields largely depend on photosynthetic carbon fixation and carbohydrate metabolism in flag leaves. The mapping of quantitative trait loci (QTLs) associated with flag leaf starch content (FLSC) in wheat (Triticum aestivum L.) was completed using unconditional and conditional QTL analyses. The FLSC of this population during the early grain-filling stage was measured at six stages in six environments. Combining unconditional and conditional QTL mapping methods, eight unconditional QTLs and nine conditional QTLs were detected, with five QTLs identified as unconditional and conditional QTLs. Four unconditional QTLs (i.e. qFLS-1B, qFLS-1D-1, qFLS-4A, and qFLS-7D-1) and one conditional QTL (i.e. qFLS-3A-1) were identified in two of six environments. Two QTLs (qFLS-1D-2 and qFLS-7D-1), which significantly affected the FLSC, were identified using the unconditional QTL mapping method, while three QTLs (i.e. qFLS-1A, qFLS-3A-1, and qFLS-7D-1) were detected using the conditional QTL mapping method. Our findings provide new insights into the genetic mechanism and regulatory network underlying the diurnal FLSC in wheat. [ABSTRACT FROM AUTHOR]

Sows are usually restricted fed during pregnancy to maximize their reproductive efficiency, which may predispose sows to a state of hunger. However, an objective measurement of hunger status has not been established. In the present study, we examined the correlation of plasma hormones and NEFA and selected the best predictors for hunger status using pregnant gilts. Three different levels of feed intake (0.5, 1.0 and 2.0 × maintenance energy intake [0.5M, 1.0M and 2.0M, respectively]) were imposed from Day 28 to 34 of gestation to create different hunger statuses in pregnant gilts. Plasma hormones related to energy homeostasis and NEFA were analyzed to quantify their response to different levels of feed intake. A total of 18 gilts (197.53 ± 6.41 kg) were allotted to 1 of 3 dietary treatments using a completely randomized design. Results showed that BW change, ADG, and G:F from Day 28 to 34 of gestation were higher (P < 0.01) for gilts on the 2.0M feeding level than for gilts on the 0.5M feeding level. Plasma acyl ghrelin concentrations showed a relatively flat pattern during the 24-h period. Plasma acyl ghrelin and NEFA concentrations and areas under the curve (AUC) were greater (P < 0.05) in gilts on the 0.5M level of feed intake than in those on the 2.0M level of feed intake. No differences were observed among the 3 feeding levels in terms of plasma glucagon-like peptide 1 and leptin concentrations. Additionally, consumption time for 1.82 kg feed on Day 35 of gestation was longer (P < 0.01) in gilts fed the 2.0M level of feed intake from Day 28 to 34 of gestation than in those on the 0.5M level of feed intake. Simple linear regression results showed that the AUC of acyl ghrelin was the best predictor for consumption time (R2 = 0.82), whereas the AUC of NEFA was the best predictor for BW (R² = 0.55) or backfat change (R2 = 0.42) from Day 28 to 34 of gestation. In conclusion, our data suggested that a relative flat pattern existed in pregnant gilts in terms of the diurnal plasma profile of acyl ghrelin and that the level of feed intake of pregnant gilts was negatively correlated with plasma concentrations of acyl ghrelin and NEFA, which, in turn, were negatively associated with feed consumption time. The AUC of acyl ghrelin and NEFA seemed to be the best predictors for hunger status of pregnant gilts. [ABSTRACT FROM AUTHOR]

Protein and starch are important in wheat quality and yield. To understand the genetic relationship between protein and starch at the quantitative trait locus (QTL)/gene level, 168 doubled haploid (DH) lines were used at three locations over 2 years. The QTLs for proteinfraction contents and starch content were analyzed by unconditional and conditional QTL mapping. We detected 17 unconditional additive QTLs (four albumin QTLs, three globulin QTLs, six gliadin QTLs, four glutenin QTLs) controlling protein-fraction contents. We detected 19 conditional QTLs (five albumin QTLs, three globulin QTLs, five gliadin QTLs, six glutenin QTLs) based on starch content. Of these QTLs, QAlu1B, QGlo6A, QGli1B, QGli7A, QGlu1B and QGlu1D increased the protein-fraction contents independent of the starch content. These QTLs could regulate the usual inverse relationship between protein and starch in wheat seeds. The results could possibly be used in the simultaneous improvement of grain protein and starch content in wheat breeding. [ABSTRACT FROM AUTHOR]

Schisandrin B is an active monomer of the Chinese magnolia vine (Schisandra chinensis) that can reduce transaminase activity in liver cells, inhibit lipid peroxidation, enhance antioxidant status, has protective effects in the liver and has antitumor effects. The present study investigated the potential protective effects of schisandrin B on the p53 signaling pathway in attenuating the inflammatory response, oxidative stress and apoptosis induced by traumatic spinal cord injury (TSCI) in adult rats. Behavioral examination, inclined plate test and spinal cord water content were used to evaluate the protective effect of schisandrin B in TSCI rats. The expression levels of superoxide dismutase (SOD), malondialdehyde (MDA), nuclear factor (NF)-κB subunit p65 and tumor necrosis factor (TNF)-α were examined using ELISA kits. Western blot analysis was performed to analyze the protein expression of caspase-3 and phosphorylated (p)-p53 in TSCI rats. In the present study, schisandrin B improved behavioral examination results and the maximum angle of inclined plate test, and inhibited spinal cord water content in rats with TSCI. Notably, schisandrin B reduced the activation of traumatic injury-associated pathways, including SOD, MDA, NF-κB p65 and TNF-α, in TSCI rats. In addition, schisandrin B suppressed the TSCI-induced expression of caspase-3 and p-p53 in TSCI rats. These results indicated that schisandrin B may attenuate the inflammatory response, oxidative stress and apoptosis in TSCI rats by inhibiting the p53 signaling pathway in adult rats. [ABSTRACT FROM AUTHOR]

One of the probable adverse effects of climate change on agriculture is yield loss due to water scarcity. Assessment of meteorological drought risk with the index of crop water deficit (CWD) can help in determining appropriate adaptation strategies to counter such losses. Using daily weather data from 68 stations in Northeast China (NEC) for 1961–2010, the spatial and temporal behaviour of CWD was assessed and the sensitivity of climatic variables related to CWD during the potential growth period of maize was explored. The results indicated that the potential maize growth period decreased by 26 days due to climate warming. The deficit (i.e. a negative value for water demand) decreased from east to west and decreased gradually during 1978–1984 and sharply during 2000–2010. It is noteworthy that NEC experienced severe droughts especially in the 1970s and the 2000s, and relative humidity was the most sensitive parameter affecting evapotranspiration. Regions in the middle of Heilongjiang and Jilin should take precautions concerning climate change effects on CWD, while the northern part of NEC should take precautions concerning changes in temperature and sunshine hours. Growing late-maturing and drought-tolerant maize varieties is therefore a good option for higher production in NEC, coupled with enhancing the availability of water in this limited-rainfall region, and should form a part of the strategy to cope with climate change. [ABSTRACT FROM PUBLISHER]

The present study investigated the effects of different feeding levels during 3 short periods of gestation on gilt and litter performance, apparent total tract digestibility (ATTD) of energy and nutrients, and energy homeostasis in gilts. A total of 18 gilts were allotted to 1 of 3 dietary treatments using a completely randomized design. All gilts were fed 1 common corn-soybean meal-based diet with the amount of 1.0 maintenance energy intake (100 * BW (BW)0.75 kcal ME/d) throughout gestation except 3 periods of 7 d when dietary treatments were imposed on d 27, d 55, and d 83 of gestation. During the 3 short periods, gilts were fed 1 of 3 different feeding levels: 0.5, 1.0, and 2.0 * maintenance energy level (0.5M, 1.0M, and 2.0M, respectively). Results showed that gilts on 2.0M feeding level had higher (P < 0.05) weight gain from d 27 to 109 of gestation (37.05 vs. 15.34 kg) and greater (P < 0.05) BW change, average daily gain, and gain to feed ratio during gestation periods 1 (d 27-34) and 3 (d 83-90) when compared with gilts on 0.5M feeding level. No differences (P > 0.10) in litter performance were observed among the 3 feeding levels. Additionally, the slopes of BW change in response to feeding levels in period 1 were 4.32 kg/0.5M change from 0.5M to 1.0M feeding level and 3.72 kg/0.5M change from 1.0M to 2.0M feeding level, respectively. There were quadratic (P < 0.05) effects of feeding levels on ATTD of dry matter and gross energy during periods 1 and 2 (d 55-62). Furthermore, fasting plasma concentrations of acyl ghrelin and nonesterified fatty acid (NEFA) in period 1 were greater (P < 0.01) in gilts on 0.5M feeding level than those on 2.0M feeding level. In conclusion, increasing feeding levels during 3 short periods increased primiparous sow performance during these short periods but did not affect litter performance. ATTD of energy and nutrients, and BW change efficiency were maximized for gilts on 1.0 M feeding level. The data also indicated that sows on the lowest feeding level were exposed to negative energy balance as evidenced by the higher plasma acyl ghrelin and NEFA concentrations. [ABSTRACT FROM AUTHOR]

To enhance the surface accuracy of laser metal direct forming pieces, a method applying femtosecond laser to fabricate the cladding sidewalls is proposed in this paper. The effects of laser fluence, scanning speed and scanning strategy on the processing accuracy are studied systematically. The experimental results show that when the laser fluence increases, the roughness of cladding sidewalls also increases. The roughness of the cladding sidewall is decreased firstly and then increased with the increasing scanning speed. When the laser fluence is between 0.12 and 0.34 J/ cm2, the roughness of cladding sidewall is less than 3 µm. What is more, under single scanning strategy the sidewalls roughness is less than that when back and forth scanning method is used. [ABSTRACT FROM AUTHOR]

Although it is generally accepted that the unidentified infrared emission (UIE) features at 3.3, 6.2, 7.7, 8.6, and 11.3 µm are characteristic of the stretching and bending vibrations of aromatic hydrocarbon materials, the exact nature of their carriers remains unknown: whether they are free-flying, predominantly aromatic gas-phase molecules, or amorphous solids with a mixed aromatic/aliphatic composition are being debated. Recently, the 3.3 and 3.4 µmfeatures which are commonly respectively attributed to aromatic and aliphatic C-H stretches have been used to place an upper limit of ~2 per cent on the aliphatic fraction of the UIE carriers (i.e. the number of C atoms in aliphatic chains to that in aromatic rings). Here we further explore the aliphatic versus aromatic content of the UIE carriers by examining the ratio of the observed intensity of the 6.2 µm aromatic C-C feature (I6.2) to that of the 6.85 µm aliphatic C-H deformation feature (I6.85). To derive the intrinsic oscillator strengths of the 6.2 µm stretch (A6.2) and the 6.85 µm deformation (A6.85), we employ density functional theory to compute the vibrational spectra of seven methylated polycyclic aromatic hydrocarbon molecules and their cations. By comparing I6.85/I6.2 with A6.85/A6.2, we derive the fraction of C atoms in methyl(ene) aliphatic form to be at most ~10 per cent, confirming the earlier finding that the UIE emitters are predominantly aromatic. We have also computed the intrinsic strength of the 7.25 µm feature (A7.25), another aliphatic C-H deformation band. We find that A6.85 appreciably exceeds A7.25. This explains why the 6.85 µm feature is more frequently detected in space than the 7.25 µm feature. [ABSTRACT FROM AUTHOR]

In this paper, we consider Adomian Decomposition Method (ADM),and Variational Iteration Method (VIM), Homotopy Analysis Method (HAM), Homotopy Analysis Transform Method (HATM) to solve the Fractional-Order Logistic Equation (FOLE). Comparisons between the approximate analytical solution and exact solution of FOLE are shown. [ABSTRACT FROM AUTHOR]

Power-dependent time-resolved optical spin orientation measurements were performed on In0.1Ga0.9As quantum well (QW) and In0.5Ga0.5As quantum dot (QD) tunnel-coupled structures with an 8-nm-thick GaAs barrier. A fast transient increase of electron spin polarization was observed at the QW ground state after circular-polarized pulse excitation. The temporal maximum of polarization increased with increasing pumping fluence owing to enhanced spin blocking in the QDs, yielding a highest amplification of 174% with respect to the initial spin polarization. Further elevation of the laser power gradually quenched the polarization dynamics, which was induced by saturated spin filling of both the QDs and the QW phase spaces. [ABSTRACT FROM AUTHOR]

Hydrogen generated renewably by using solar energy has attracted increasing interest in the renewable energy research community. Hence, efficient electrocatalysts are in demand to reduce costs and energy consumption for oxygen and hydrogen evolution reaction (OER and HER) activity. Bismuth telluride (Bi2Te3)-based materials, as topological insulators (TIs), have been used to explore the fundamental properties of TIs in recent years, but investigation as functional materials for water splitting applications is still quite limited. In this work, electrocatalysts based on Bi2Te3 nanosheets have been fabricated, and the HER performance was investigated to further enhance OER electrocatalytic properties, with certain transition metals (Co, Ni, and Mo) selected to provide effective electrocatalytic sites. Therefore, the bifunctional catalyst Bi2Te3@CoNiMo was designed for synthesis by a solvothermal and chemical deposition route. The catalyst electrode, Bi2Te3@CoNiMo loaded on Ni foam, exhibits higher activity towards both the oxygen and the hydrogen evolution reactions than some traditional metallic catalysts in alkaline electrolytes. The difference in the HER and OER metrics (ΔE = 1.41 V) is comparable to the theoretical value (1.23 V), so that this reaction can be easily driven by a solar cell. [ABSTRACT FROM AUTHOR]

The highly efficient CuO/Co3O4 composite photocatalyst with different morphologies has been synthesized directly on Cu wire mesh by controlling the composition of cobalt-containing solid precursors via a simple hydrothermal method. The structure morphology and composition of the composite photocatalyst have been characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and UV-visible diffuse reflectance spectra. The photocatalytic result shows that the CuO/Co3O4 coaxial heterostructure is easy to recycle and exhibit enhanced photodegradation activity for methylene blue compared to single CuO nanorod arrays under full spectrum solar light irradiation. The enhanced photocatalytic efficiency of the composite could be ascribed to the synergistic effect of CuO and Co3O4. This study provides a general and effective method in the fabrication of 1D composition NRs with sound heterojunctions that show enhancement of photocatalytic performance and facility of recycling. [ABSTRACT FROM AUTHOR]

Cancer initiating cells (CICs) are responsible for the unrestrained cell growth and chemoresistance of malignant tumors. Histone demethylation has been shown to be crucial for self-renewal/differentiation of stem cells, but it remains elusive whether lysine-specific demethylase 1 (LSD1) regulates the stemness properties of CICs. Here we report that the abundant expression of leucine-rich repeat-containing G-protein-coupled receptor 5 (Lgr5) is associated with the progression of hepatocellular carcinoma (HCC). Lgr5+ HCC cells behave similarly to CICs and are highly tumorigenic and resistant to chemotherapeutic agents. Importantly, Lgr5+ cells express higher levels of LSD1, which in turn regulates Lgr5 expression and promotes the self-renewal and drug resistance of Lgr5+ CICs. Mechanistically, LSD1 promotes β-catenin activation by inhibiting the expression of several suppressors of β-catenin signaling, especially Prickle1 and APC in Lgr5+ CICs, by directly regulating the levels of mono- and di-methylation of histone H3 lysine-4 at the promoters of these genes. Furthermore, LSD1-associated activation of the β-catenin signaling is essential for maintaining the activity of Lgr5+ CICs. Together, our findings unravel the LSD1/Prickle1/APC/β-catenin signaling axis as a novel molecular circuit regulating the stemness and chemoresistance of hepatic Lgr5+ CICs and provide potential targets to improve chemotherapeutic efficacies against HCC. [ABSTRACT FROM AUTHOR]

We investigate ensemble electron spin dephasing in self-assembled InGaAs/GaAs quantum dots (QDs) of different lateral sizes by employing optical Hanle measurements. Using low excitation power, we are able to obtain a spin dephasing time T*2 (in the order of ns) of the resident electron after recombination of negative trions in the QDs. We show that T*2 is determined by the hyperfine field arising from the frozen fluctuation of nuclear spins, which scales with the size of QDs following the Merkulov-Efros-Rosen model. This scaling no longer holds in large QDs, most likely due to a breakdown in the lateral electron confinement. [ABSTRACT FROM AUTHOR]

We investigate ensemble electron spin dephasing in self-assembled InGaAs/GaAs quantum dots (QDs) of different lateral sizes by employing optical Hanle measurements. Using low excitation power, we are able to obtain a spin dephasing time T*2 (in the order of ns) of the resident electron after recombination of negative trions in the QDs. We show that T*2 is determined by the hyperfine field arising from the frozen fluctuation of nuclear spins, which scales with the size of QDs following the Merkulov-Efros-Rosen model. This scaling no longer holds in large QDs, most likely due to a breakdown in the lateral electron confinement. [ABSTRACT FROM AUTHOR]

We evaluated the effect of AAV2- and 17-AAG (17-N-allylamino-17-demethoxygeldanamycin)-mediated upregulation of Hsp70 expression on the survival of retinal ganglion cells (RGCs) injured by optic nerve crush (ONC). AAV2-Hsp70 expression in the retina was primarily observed in the ganglion cell layer. Approximately 75% of all transfected cells were RGCs. RGC survival in AAV2-Hsp70-injected animals was increased by an average of 110% 2 weeks after the axonal injury compared with the control. The increase in cell numbers was not even across the retinas with a maximum effect of approximately 306% observed in the inferior quadrant. 17-AAG-mediated induction of Hsp70 expression has been associated with cell protection in various models of neurodegenerative diseases. We show here that a single intravitreal injection of 17-AAG (0.2 ug ul−1) results in an increased survival of ONC-injured RGCs by approximately 49% compared with the vehicle-treated animals. Expression of Hsp70 in retinas of 17-AAG-treated animals was upregulated approximately by twofold compared with control animals. Our data support the idea that the upregulation of Hsp70 has a beneficial effect on the survival of injured RGCs, and the induction of this protein could be viewed as a potential neuroprotective strategy for optic neuropathies. [ABSTRACT FROM AUTHOR]