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Hydrogen technology is widely considered a novel clean energy source, and electrolysis is an effective method for hydrogen evolution. Therefore, efficient hydrogen evolution reaction (HER) catalysts are urgently needed to replace precious metal catalysts and meet ecological and environmental protection standards. Herein, Ni–Mn–P electrocatalysts are synthesized using facile electrodeposition technology. The influence of the Mn addition on the catalytic behavior is studied by the comprehensive analysis of catalytic performance and morphology of the catalysts. Among them, the Ni–Mn–P0.01 catalyst exhibits small coral-like structures, greatly improving the adsorption and desorption of hydrogen ions and reducing the overpotential hydrogen evolution. Consequently, overpotential at 10 mA cm−2 electric current density is 113 mV, and the value of the Tafel slope achieves 74 mV/dec. Furthermore, the Ni–Mn–P catalyst shows long-time (20 h) stability at current densities of 10 and 60 mA/cm2. The results confirm that the synergistic effect of Ni, Mn, and P accelerates the electrochemical reaction. Meanwhile, the addition of manganese element can change the micromorphology of the catalyst, thereby exposing more active sites to participate in the reaction, enhancing water ionization, improving the catalytic performance. This study opens a new way toward improving the activity of the catalyst by adjusting Mn concentration during the electrodeposition process.

The TiO2/Mn0.2Cd0.8S hollow heterojunction with Mn/Cd bimetallic synergy is prepared via a continuous chemical-hydrothermal-etching method. There, the TiO2 shell and Mn0.2Cd0.8S nanoparticles were deposited by continuous chemical-hydrothermal method on the surface of SiO2 template, and subsequently the SiO2 template was etched via a chemical method. Evaluated by HER, the as-prepared TiO2/Mn0.2Cd0.8S hollow heterojunction exhibits an obvious photocatalytic enhancement to about ~5822.94 μmol/g∙h(~40 folds of TiO2, ~7 folds of Mn0.2Cd0.8S), which can be mainly ascribed to that, the narrow band gap of Mn0.2Cd0.8S can increase the visible light energy utilization, the TiO2/Mn0.2Cd0.8S heterojunction and Mn/Cd bimetallic synergy can separate/transfer the photo-generated charge carriers efficiently, and the sufficient specific surface areas and actives from 3D hollow structure can promote the charge carrier diffusing into water quickly for achieving H2 generation. Additionally, the hollow 3D structure can provide a decent physical-chemical stability to improve the photocatalytic stability.

The diffusion of defects (e.g., vacancies and interstitials) and elements used for dating (e.g., He and Pb) in a mineral structure is a thermal process: This is the primary assumption used to determine the age and thermal history of minerals. For instance, thermal history reconstruction, through the number and length distribution of tracks produced by spontaneous fission of 238U, is obtained by assuming a thermal event to be the only energy source for shortening of fission tracks. Here, we report a new, non-thermal energy source that induces additional shortening of fission tracks by the irradiation of alpha-recoils from the alpha-decay of 238U and 232Th. We simulate alpha-decay induced track-shortening by combining ion accelerator irradiations with transmission electron microscopy. This allows for the first observation of track-shrinkage during in situ ion irradiation. We show that rather than alpha-particles, alpha-recoils induce a significant shortening of fission tracks by nuclear-collisions. The shortening of track-length can be quantified as a function of alpha-decay event dose. However, apatite is less sensitive than zircon to this non-thermal process. The findings exemplify the interactions among different types of self-irradiation from alpha-particles, alpha-recoils and fission-fragment nuclei in single mineral grains and have important implications for the use of zircon and apatite for radiometric dating and thermochronology.

Black rockfish (Sebastes schlegelii) is a viviparous teleost fish whose spermatozoa were transferred into the female ovary cavity and stored for up to five months and then fertilized with the matured eggs. There is no clarity about the molecular characteristics of ovarian follicles during female sperm storage in Sebastes schlegelii. In this study, histological observation, transcriptomic analysis and hormone level detection were performed in ovaries at stages of pre-mating (PRM), post-mating (POM) and pre-fertilization (PRF). Histological observation displayed that oocytes developed from the primary growth (PG) stage to the mature stage during the three stages. Furthermore, somatic cells around the oocyte were proliferated and spermatozoa were found near the layer of epithelial cells. Transcriptomic analysis showed that there were 437 and 747 differentially expressed genes (DEGs) in ovarian comparison of PRM-vs-POM and POM-vs-PRF, respectively. GO enrichment and KEGG analysis revealed that lots of DEGs from PRM-vs-POM were linked to immune-related pathways, such as antigen processing and presentation, immune response, and complement and coagulation cascade. Meanwhile, seven DEGs associated with immune response were differentially expressed after spermatozoa treatment in ovarian tissue in vitro. While the DEGs from POM-vs-PRF were mostly enriched in the pathways related to homeostasis maintenance and cellular junction and metabolism. In addition, we found increased estrogen (E2) and 11-ketotestosterone (11-KT) level and decreased testosterone level in ovarian follicles during the sperm storage period by ELISA, suggesting that sex hormones are involved in the dynamic change of ovarian follicles. In total, this study could provide new hints for understanding the immune adaption and developmental signatures of ovarian follicles post copulation in black rockfish and other viviparous fish.

Objective Bariatric surgery acutely improves glucose control, an effect that is generally sustained for years in most patients. The acute postoperative glycemic reduction is at least partially mediated by enhanced incretin secretion and islet function, and occurs independent of caloric restriction, whereas the sustained improvement in glucose control is associated with increased insulin sensitivity. However, studies in humans with bariatric surgery suggest that these elevations are not static but undergo coordinated regulation throughout the postoperative time course. The studies described here test the hypothesis that incretin secretion, islet function, and peripheral insulin sensitivity undergo temporal regulation following bariatric surgery as a means to regulate glucose homeostasis. Methods Incretin secretion, islet function, and insulin sensitivity in mice with vertical sleeve gastrectomy (VSG) were compared to sham-operated controls that were pair-fed for 90d, matching food consumption and body-weight between groups. Results Glucose clearance and insulin secretion were enhanced in VSG mice compared to controls during mixed-meal tolerance tests (MMTT) at 12 and 80 days postoperatively, as were prandial GLP-1, GIP, and glucagon levels. Insulin sensitivity was comparable between groups 14d after surgery, but significantly greater in the VSG group at day 75, despite similar body-weight gain between groups. Glucose stimulated insulin secretion was greater in VSG mice compared to controls in vivo (I.P. glucose injection) and ex vivo (islet perifusion) indicating a rapid and sustained enhancement of β-cell function after surgery. Notably, glycemia following a MMTT was progressively higher over time in the control animals but improved in the VSG mice at 80d despite weight regain. However, meal-stimulated incretin secretion decreased in VSG mice from 10 to 80 days postoperative, as did meal-stimulated and I.P. glucose-stimulated insulin secretion. This occurred over the same time period that insulin sensitivity was enhanced in VSG mice, suggesting postoperative islet output is tightly regulated by insulin demand. Conclusions These data demonstrate a dynamic, multifactorial physiology for improved glucose control after VSG, whereby rapidly elevated insulin secretion is complimented by later enhancements in insulin sensitivity. Critically, the glucose lowering effect of VSG is demonstrably larger than that of caloric-restriction, suggesting these adaptations are mediated by surgical modification of gastrointestinal anatomy and not weight-loss per se., Highlights • β-cell glucose sensitivity is enhanced 90d after VSG compared to controls, coincident with improved glucose tolerance. • Prandial GLP-1 and GIP are elevated 12d following VSG but return to preoperative levels 80d after VSG. • Insulin sensitivity is enhanced 75d after surgery, but not 14d after surgery, in mice with VSG compared to controls. • Mixed-meal glucose control is improved from 12d to 80d in VSG mice, but worsens in controls despite similar body-weight.

P450c17, a key enzyme in the steroid generation pathway, plays an important role in the production of sex steroid and cortisol. In this study, two cyp17 gene isoforms, Pocyp17-I and Pocyp17-II were isolated from Paralichthys olivaceus gonads. Domain architecture analysis of Pocyp17-I and Pocyp17-II revealed that they had three regions important to enzymatic function. Structural analysis showed that Pocyp17-I and Pocyp17-II had 8 and 9 exons respectively, and the difference was caused by the insertion of an extra intron (intron1) in the latter. Quantitative real-time polymerase chain reaction results indicated that the expression of these two genes showed sexually dimorphism that Pocyp17-I and Pocyp17-II were highest expressed in testis and ovary, respectively. The in situ hybridization analysis of gonads indicated that Pocyp17-I and Pocyp17-II mRNA were both detected in oocytes, spermatocytes and Sertoli cells. After injection of androgen and estrogen (17α-methyltestosterone, 17β-estradiol) of different concentrations, the expression level of Pocyp17-I decreased significantly (P 0.01), whereas estrogen had no influence on Pocyp17-II, but androgen upregulated the expression of Pocyp17-II (P 0.05). Moreover, Pocyp17-I expression level was down-regulated significantly by NR0b1 but up-regulated by NR5a2 (P 0.05), whereas Pocyp17-II expression level was down-regulated significantly by NR0b1 and NR5a2 (P 0.05). All these results demonstrated that there were differences in expression patterns, feedback actions of sex hormones and transcriptional regulations between cyp17-I and cyp17-II, which revealed that cyp17-I and cyp17-II might perform different functions in sex hormones biosynthesis and gonadal differentiation in Japanese flounder.

Spermatogenesis is the process during which spermatocytes undergo meiosis to produce spermatozoa. Sertoli-Sertoli and Sertoli-spermatogenic junctions are important for the maturity and release of sperms. These junctions, which are related to male infertility, have been reported in mammals but are unclear in teleost species. In this study, the RNAs in the gonads of 1.5-year-old Japanese flounders were sequenced using Illumina. The miRNA expression profiles in the mature gonads of males and females were characterized. A total of 277 mature miRNAs were screened in both gonads. Among them, 25 miRNAs were expressed differently in the ovary and testis. Afterward, miR-1388 was selected for its high expression level in the ovary. Gene ontology analysis revealed that the target genes of miR-1388 were highly involved in cell-cell adhesion. Nectin2l, the target of miR-1388, is a Ca-independent cell adhesion molecule that was demonstrated to be testis-biased via quantitative real-time PCR and located in Sertoli cells and spermatocytes via in situ hybridization. Our present study predicted the potential functions of sex-biased miRNA and indicated that miR-1388 regulates cell junctions by inhibiting nectin2l, which may have an important role in the later development of testes. Our study lays the ground work of miRNAs' function in the cell junctions of germ cells.

Objective The blood–brain barrier (BBB) regulates the entry of substrates and peptides into the brain. Ghrelin is mainly produced in the stomach but exerts its actions in the central nervous system (CNS) by crossing the BBB. Once present in the CNS, ghrelin can act in the hypothalamus to regulate food intake, in the hippocampus to regulate neurogenesis, and in the olfactory bulb to regulate food-seeking behavior. The goal of this study was to determine whether the primary signaling receptor for ghrelin, the growth hormone secretagogue receptor (GHSR), mediates the transport of ghrelin from blood to brain. Methods We utilized the sensitive and quantitative multiple-time regression analysis technique to determine the transport rate of mouse and human acyl ghrelin (AG) and desacyl ghrelin (DAG) in wildtype and Ghsr null mice. We also measured the regional distribution of these ghrelin peptides throughout the brain. Lastly, we characterized the transport characteristics of human DAG by measuring the stability in serum and brain, saturability of transport, and the complete transfer across the brain endothelial cell. Results We found the transport rate across the BBB of both forms of ghrelin, AG, and DAG, were not affected by the loss of GHSR. We did find differences in the transport rate between the two isoforms, with DAG being faster than AG; this was dependent on the species of ghrelin, human being faster than mouse. Lastly, based on the ubiquitous properties of ghrelin throughout the CNS, we looked at regional distribution of ghrelin uptake and found the highest levels of uptake in the olfactory bulb. Conclusions The data presented here suggest that ghrelin transport can occur independently of the GHSR, and ghrelin uptake varies regionally throughout the brain. These findings better our understanding of the gut-brain communication and may lead to new understandings of ghrelin physiology., Highlights • Ghrelin is transported across the BBB in the absence of GHSR. • Human DAG is transported the fastest compared to mDAG > hAG > mAG. • The olfactory bulb contained the greatest amount of ghrelin.

Cs2SnBr6, one promising material applied in perovskite solar cells, has been investigated up to 20 GPa by synchrotron X-ray diffraction and Raman spectroscopy. Both experimental data demonstrate that no phase transition occurs up to 20 GPa. By fitting the third-order Birch-Murnaghan equation of state, we have obtained V0 = 1288 (14) A3, K0 = 11 (1) GPa and K0′ = 7 (1). The ultralow value of bulk modulus K0 demonstrates the soft nature of Cs2SnBr6. Combining calculated values with experimental results, we find that x coordinate of Sn (x,0,0) atoms increases and Sn Br bond lengths get shortened on compression. We have assigned vibrational peaks of Cs2SnBr6 in Raman measurements, and all the three Raman bands present nonlinear correlations with pressure.

Although modifying high-pressure behavior through the particle-size of a material is well recognized, a clear mechanism, underlying the start and subsequent growth of a high-pressure phase, remains elusive. Here, we investigate the effects of particle-size on the formation of reidite (ZrSiO4, I41/a), a high-pressure phase of zircon (ZrSiO4, I41/amd), by comparing zircon nanoparticles with bulk. This is done by high pressure Raman scattering and synchrotron X-ray diffraction experiments on zircons pressurized in diamond anvil cells and subsequent transmission electron microscopy analysis of quenched samples. As compared to bulk, the larger surface energy of nanoparticles is the cause of a higher critical pressure required to start the transition to reidite. However, after passing the critical pressures, the similar growth trends between nanoparticles and bulk indicate that the reidite growth is dependent on the core, rather than the surface. These results are important to identify craters caused by meteorite impacts using reidite as a high-pressure indicator, as nanoparticles are formed in naturally-occurring, highly radiation-damaged zircon.

We propose and experimentally demonstrate a switchable multi-wavelength Erbium-doped fiber laser that employs cascaded weakly-coupled few-mode fiber (FMF) Sagnac fiber loops with mode differential delay line. A comb filter of multiple specific wavelengths is performed by incorporating a weakly-coupled FMF in cascaded Sagnac fiber loops. The incorporation of the weakly-coupled FMF is realized with all-fiber mode multiplexer/demultiplexer (MUX/DEMUX), which can simultaneously generate transversal LP01 and LP11 modes. The comb filter characteristics of cascaded Sagnac fiber loops are simulated and analyzed by Jones matrix. By adjusting the polarization controllers (PCs), the fiber laser can operate in single-, dual-, and triple-wavelength laser states around C band. The side mode suppression ratio is larger than 30.0 dB. Moreover, the laser output stabilities for single-, dual-, and triple-wavelength lasing are investigated in a range of over 30 mins at room temperature. Experimental results indicate that this work has potential applications in WDM systems, sensing, and instrument testing.

Bifunctional catalyst, as a feasible way to produce hydrogen, has been regarded as an effective issue for mitigation of the greenhouse effect, and thus has attracted extensive attention. Inspired by the traditional electrodeposition technology, we report a fast self-etching electrodeposition method to construct copper-incorporated three-dimensional Ni-Cu coated on copper sheets as a superior bifunctional catalyst. During the electrodeposition process, the copper substrate was corroded to form ammonium copper ions by ingenious design of the concentration of electrolyte, including ammonium chloride and sodium chloride. Meanwhile, we observe that the ratio of Ni to Cu could be changed via varying the current density. The optimized hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) overpotentials are 76 mV and 290 mV at 10 mA cm−2, respectively, which outperform the most reported bifunctional electrocatalysts until now. The calculation further demonstrates that the theoretical hydrogen desorption energy and OER overpotential of Ni-Cu are better than those of pure Ni and Cu. The prepared Ni-Cu electrocatalyst exhibits remarkable stability, especially in the HER reaction process stability test up to 50 h. The successful preparation of Ni-Cu electrocatalyst provides more possibility in the traditional electrodeposition synthesis of high performance electrocatalysts.

A foundation of the modern technology that uses single-crystal silicon has been the growth of high-quality single-crystal Si ingots with diameters up to 12 inches or larger. For many applications of graphene, large-area high-quality (ideally of single-crystal) material will be enabling. Since the first growth on copper foil a decade ago, inch-sized single-crystal graphene has been achieved. We present here the growth, in 20 min, of a graphene film of (5 × 50) cm2 dimension with >99% ultra-highly oriented grains. This growth was achieved by: (1) synthesis of metre-sized single-crystal Cu(1 1 1) foil as substrate; (2) epitaxial growth of graphene islands on the Cu(1 1 1) surface; (3) seamless merging of such graphene islands into a graphene film with high single crystallinity and (4) the ultrafast growth of graphene film. These achievements were realized by a temperature-gradient-driven annealing technique to produce single-crystal Cu(1 1 1) from industrial polycrystalline Cu foil and the marvellous effects of a continuous oxygen supply from an adjacent oxide. The as-synthesized graphene film, with very few misoriented grains (if any), has a mobility up to ∼23,000 cm2 V−1 s−1 at 4 K and room temperature sheet resistance of ∼230 Ω/□. It is very likely that this approach can be scaled up to achieve exceptionally large and high-quality graphene films with single crystallinity, and thus realize various industrial-level applications at a low cost.

We propose an effective numerical modal decomposition (MD) algorithm for few/multi-mode fibers using a deep convolution neural network (CNN) model in this paper. MD is an available method to reveal modal coefficients. However, with the increase of the superimposed eigenmodes number, the performance of MD will deteriorate due to the modal ambiguity. Our aim is to attain both modal amplitudes and phases from the near-field intensity profile, while minimizing the effect of modal ambiguity as much as possible. Specifically, we train the model with the combination of a modal coefficients loss and two reconstruction losses (near-field and far-field intensity reconstruction losses), which ensures the uniqueness of the solution. With extensive simulational results, we demonstrate that our model is able to mitigate the problem of modal ambiguity and attain accurate modal coefficients (The correlation is above 1.9937 for all modal cases) in a high-speed way. Additionally, the influence of noise and task weights are comprehensively studied. Our proposed technique is useful to mitigate the modal ambiguity.

A switchable multi-wavelength figure eight Erbium-doped fiber (EDF) laser with linearly-polarized (LP) beam generation in the C-band region is proposed and experimentally demonstrated. Spatial-mode beating occurs owing to effect of multi-mode interference in the weakly-coupled few-mode fiber (FMF). A bandpass filter of multiple specific wavelengths is created by incorporating a weakly-coupled FMF with a Sagnac fiber loop. The LP modes are generated by cascaded mode-selective couplers (MSCs), which are designed and fabricated by tapering the proposed FMF with single-mode fiber (SMF). Combination of the cascaded MSCs and a simple N × 1 optical switch is employed to switch the LP modes. In experiments, the proposed fiber laser delivers versatile lasing outputs in states of single-, dual-, triple-wavelength oscillations for LP01, LP11 and LP21 modes. We investigate the stabilities for LP01, LP11, LP21 modes in 24-min. Moreover, the mode intensity profiles, optical signal-noise ratios (OSNRs) of lasing output and slope efficiencies are also measured. The proposed fiber laser has promising applications in WDM-MDM optical fiber communication systems, optical fiber sensor systems, optical instruments and spectroscopy.

Perturbations in carbohydrate, lipid, and protein metabolism contribute to obesity-induced type 2 diabetes (T2D), though whether alterations in ketone body metabolism influence T2D pathology is unknown. We report here that activity of the rate-limiting enzyme for ketone body oxidation, succinyl-CoA:3-ketoacid-CoA transferase (SCOT/Oxct1), is increased in muscles of obese mice. We also found that the diphenylbutylpiperidine pimozide, which is approved to suppress tics in individuals with Tourette syndrome, is a SCOT antagonist. Pimozide treatment reversed obesity-induced hyperglycemia in mice, which was phenocopied in mice with muscle-specific Oxct1/SCOT deficiency. These actions were dependent on pyruvate dehydrogenase (PDH/Pdha1) activity, the rate-limiting enzyme of glucose oxidation, as pimozide failed to alleviate hyperglycemia in obese mice with a muscle-specific Pdha1/PDH deficiency. This work defines a fundamental contribution of enhanced ketone body oxidation to the pathology of obesity-induced T2D, while suggesting pharmacological SCOT inhibition as a new class of anti-diabetes therapy.

Reductions in calorie intake contribute significantly to the positive outcome of bariatric surgeries. However, the physiological mechanisms linking the rerouting of the gastrointestinal tract to reductions in sugar cravings remain uncertain. We show that a duodenal-jejunal bypass (DJB) intervention inhibits maladaptive sweet appetite by acting on dopamine-responsive striatal circuitries. DJB disrupted the ability of recurrent sugar exposure to promote sweet appetite in sated animals, thereby revealing a link between recurrent duodenal sugar influx and maladaptive sweet intake. Unlike ingestion of a low-calorie sweetener, ingestion of sugar was associated with significant dopamine effluxes in the dorsal striatum, with glucose infusions into the duodenum inducing greater striatal dopamine release than equivalent jejunal infusions. Consistently, optogenetic activation of dopamine-excitable cells of the dorsal striatum was sufficient to restore maladaptive sweet appetite in sated DJB mice. Our findings point to a causal link between striatal dopamine signaling and the outcomes of bariatric interventions.

Recently, nitrogen-doped carbon dots (NCDs) have attracted considerable interest since nitrogen (N) doping could effectively tailor the electronic properties and the chemical reactivity of carbon dots (CDs) for advanced potential applications. Herein, a one-step pyrolysis method was presented for synthesizing the NCDs with excellent water solubility, good stability and a high quantum yield of ca. 28%. The detection performance of NCDs for the antibacterial drugs was further explored, and it was proved to effectively enhance the fluorescence due to the strong interaction between the NCDs and antibacterial drugs. (C) 2014 Elsevier B.V. All rights reserved.

Objective In Chinese adults, the trend of central obesity and its longitudinal association with hypertension, independent of general obesity, was examined. Methods A 12-year longitudinal analysis was conducted using data retrieved from the China Health and Nutrition Survey. This study examined 6096 individuals (normotensive in 1997) who were followed up with in 2000, 2004, 2006, and 2009. Prevalence of hypertension in 2009 was predicted by baseline central obesity and waist circumference changes during a 12-year follow-up period along with confounding covariates using multiple logistic regressions. Results Between 1997 and 2009, the prevalence of central obesity increased from 17.3% to 39.4% and was highest among individuals ≥ 60 years of age in 1997. By 2009, 26.8% of the participants developed hypertension. The odds ratio of developing hypertension during the 12-year study period for Chinese adults with central obesity at baseline was 1.79 (95% confidence interval = 1.36–2.35) compared to those without central obesity, controlling for general obesity, demographics, smoking/drinking behavior, and fat intake. Conclusions Among Chinese adults, central obesity increases the risk for developing hypertension later in life, even after controlling for general obesity, smoking, drinking, and high fat intake among other factors. Waist circumference should be targeted in the efforts of hypertension prevention.

Spin-dependent thermoelectric transport properties have been experimentally studied on a micro-structured device based on epitaxially grown 75-nm-thick Co2Ti0.6V0.4Sn0.75 Heusler film with integrated heater and thermometers. The anomalous Nernst coefficient is found to be 0.5 μV/K at 50 K. Thermoelectric power in both longitudinal and transverse directions have been measured with magnetic field rotated in-plane. Asymmetric peaks and valleys are observed at particular in-plane field angle around 25 K. These anomalous peaks show novel magnetic hysteresis due to the interplay between the magnetization and the temperature gradient. These complex behaviors of thermoelectric effect during magnetization reversal still need to be understood.