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A novel nonlinear optical switch based on a single mode fiber – graded index multimode fiber (GIMF) – single mode fiber (SMS) twined into polarization controller (PC) was proposed as a saturable absorber (SA), to generate ultrashort pulse in fiber laser. The SA device geometry, where a sandwiched GIMF section spliced to two standard SMF at both ends of GIMF, was coiled into a PC. By properly tuning the paddles of PC, mode-locking can be easily realized and the nonlinear saturable absorption characteristics of SMS-SA was changed. In the experiment, the modulation depth of the SMS-SA containing 0.6 m GIMF can be observed 9%, 10.5%, 21.7%, respectively. Based on SMS-SA mode-locking, the stable ultrafast pulse duration of 559 fs, with the FWHM bandwidth of 6.84 nm were generated. The fundamental repetition rate of 25 MHz and wavelength-tuning range of 14 nm can be obtained by adjusting the paddles. The SMS-SA excellent tunable nonlinear optical properties and all-fiber structure have strong potential application in the field of ultrafast photonics.

The rapid development of nutrition science is embracing digital transformation to generate large amounts of data. Precision nutrition and "Big Data" place increasing demand for data repositories and visualization, which enhances the digital transformation. We defined the need for an integrated nutrition data platform as a web-based platform that can collect, store, track, analyze, monitor, and visually display key metrics in nutrition and health while allowing users to interact with visuals and download data provided in the platform. Interactive dashboards create new opportunities for scholars and practitioners to generate and test hypotheses. We present the development and implementation of the Global Nutrition and Health Atlas (GNHA; https://sites.tufts.edu/gnha/), an open-access online platform covering nutrition and health data with 26 themes and 500+ indicators from 190+ countries up to 30 y. We view GNHA as an interactive tool aiming to share information and perspectives and foster collaborations and innovations.

Facing environmental pollution, the development of semiconductor photocatalysts with efficient electron-hole pairs separation is necessary for better performance optimization and utilization. Here, a direct Z-scheme BiOBr–NiO-x% (x ​= ​5, 10, 20, 30) photocatalysts with outstanding photocatalytic activity for dye degradation were prepared via the hydrothermal process. The XRD, XPS, FESEM, HRTEM and UV–vis DRS were used to characterize the components, phase structure, morphology and optical properties of the prepared samples. The prepared nano-flower like BiOBr–NiO-x% (x ​= ​5, 10, 20, 30) composites had an extensive visible light absorption range and more vigorous absorption intensity than pure BiOBr. All the prepared composites exhibited better photocatalytic activity for rhodamine (RhB) degradation than that of pure BiOBr, with BiOBr/NiO-20% showing the best photocatalytic efficiency. The photocatalytic efficiency had reached 98% within 50 ​min for the BiOBr/NiO-20% composite. Due to the tight interfacial contact and matching band positions between BiOBr and NiO, a direct Z-scheme BiOBr/NiO heterojunction was built, which accelerated the visible light absorption, superior separation of photoinduced electron-hole pairs in space and improved the oxidation and reduction capacity of the catalysts, further leading to the excellent photocatalytic activity for degradation of RhB.

Thermo-mechanical experiments at different elevated temperatures are carried out for tensile and shear-dominant specimens extracted from warming forming materials of 7075 aluminum alloy and 22MnB5 boron steel, respectively. A specimen-embedded furnace jointed by temp-control system to perform the high temperature shear experiments. Driven by microscale anisotropic plastic flow, damage is embedded in each slip system and damage evolution is controlled by the preferential dislocation slip. Combined with microscale damage and dislocation density based constitutive model, an advanced crystal plasticity method is proposed to perform predictions of mechanical behavior of face-center-cubic materials at various temperatures. Reasonable agreement is obtained between experimental and numerical results for different specimens, temperature conditions and materials. This approach simultaneously captures the strain hardening rate, damage softening, non-linear post-necking and fracture strain. Microstructural effects on ductile fracture are tracked and investigated including dislocation density and crystallographic orientation. The results show that local dislocation density rise is associated with damage initiation. Different fracture morphologies and necking paths are caused by distinct initial misorientation distributions in comparison with experimental observation of 7075 aluminum alloy. Local misorientations are investigated and critical misorientation ranges are computed for promoting void growth in zigzag and straight fracture morphologies. Schmid factor is computed as not necessary variable to trigger void growth.

International audience; In an aqueous electrolyte under an anodic polarization, most of the conductive polymers could undergo an overoxidation due to the hydroxyl radicals formed during water oxidation. Regarding poly(3,4-ethylenedioxythiophene) (PEDOT) only a few reports studied its overoxidation. In this paper, we propose a facile and rapid strategy to prepare an ultrathin (15 nm), pinhole-free and non-conductive overoxidized PEDOT film by electropolymerization of EDOT under potentiostatic conditions in the presence of solely weak-acid ions in the monomer solution. The influence of the pH of this solution as well as the applied potential was studied notably by electrochemical impedance spectroscopy. It was pointed out that the PEDOT film is overoxidized when its electrosynthesis is performed in an aqueous monomer solution of pH 10.5, at 1.1 V/SCE, the monomer solution containing only weak-acid ions as anions (phosphates or carbonates). XPS analyses show that some C and S atoms of the film are oxidized leading to a break of the polymer conjugation and therefore to a decrease of its electronic conductivity. Finally, after adding in the monomer phosphate solution of pH 10.5 perchlorate ions that allow to avoid total overoxidation of the film formed at the very beginning of the process, PEDOT nanowires were obtained.

H(2)O(2) is a crucial substrate of thyroproxidase (TPO) to iodinate thyroglobulin and synthesize thyroid hormones in thyroid. ThOX proteins (thyroid oxidase) also called Duox are believed to be responsible for H(2)O(2) generation. Duoxs expressed in transfected cells do not generate an active system, nor permit their membrane localization suggesting that other proteins are required to fulfill these functions. In this study, we demonstrate interactions of Duoxs with TPO and with p22(phox) without any effect on Duox activity. By yeast two-hybrid method using EF-hand fragment of dog Duox1 as the bait we have isolated EFP1 (EF-hand binding protein 1), one partner of Duoxs that belongs to the thioredoxin-related protein family. EFP1 shares moderate similarities with other members of thioredoxin-related proteins, but the characteristic active site and the folding structures are well conserved. EFP1 can be co-immunoprecipitated with Duoxs in transfected COS cells as well as in primary cultured human thyrocytes. It interacts also with TPO but not thyroglobulin. Immunofluorescence studies show that EFP1 and Duox proteins are co-localized inside the transfected cells, suggesting that EFP1 is not sufficient to induce either the expression of Duox at the plasma membrane or to permit H(2)O(2) production. EFP1 and Duox mRNA share similar distribution in nine different tissues. These results suggest that EFP1 could be one of the partners in the assembly of the multiprotein complex constituting the thyroid H(2)O(2) generating system but is certainly not sufficient to permit H(2)O(2) generation.

We have recently cloned two thyroid-specific cDNAs encoding new members of the NADPH oxidase family. ThOX1 and ThOX2 proteins are colocalized with thyroperoxidase at the apical membrane of human thyroid cells. In the present study we have determined their subcellular localization and maturation in relation to their enzymatic activity. A majority of ThOX proteins accumulated inside the cell and only a small fraction was expressed at the surface. Western blots demonstrated that ThOX's are glycoproteins of 180,000 and 190,000. When totally deglycosylated the molecular weight of both ThOX1 and ThOX2 drops to 160,000. Ca(2+) stimulates the basal H(2)O(2) generation in PC Cl3 cells at a level corresponding to 20% of the leukocyte H(2)O(2) production stimulated by PMA. Nonthyroid cell lines transfected with ThOX1 and ThOX2 show only a single immunoreactive band in Western blot analysis, corresponding to the protein of 180,000. This "immature" protein remains exclusively intracellular and does not present any enzymatic activity. This is not modified by coexpression of thyroperoxidase and p22(Phox). Transfection of ThOX cDNAs into PLB-XCGD cells does not reconstitute their NADPH oxidase activity. We conclude that (1) the thyroid contains some elements of the leukocyte H(2)O(2)-generating system but not all of them; (2) ThOX's are predominantly or exclusively located inside the cell in thyrocytes or in transfected cells, respectively, and as such they are inactive; (3) ThOX's cannot replace gp91(Phox) in the leukocyte; and (4) the thyroid H(2)O(2)-generating system is analogous to the leukocyte system with regard to ThOX's and gp91(Phox) but very different in other aspects. Additional thyroid-specific components are probably required to get complete protein processing and full enzymatic activity in the thyroid.

Background A substantial increase in nutrition-related non-communicable diseases has taken place concomitantly with the Chinese nutrition transition. Our study focused on school-aged Chinese children to investigate the prevalence of cardiometabolic risk factors and their association with specific dietary factors. Methods We included 663 children of 7–12 years who participated in the 2009 China Health and Nutrition Survey. Dietary intake and detailed individual and household data were obtained by trained interviewers during home visits. Anthropometric measures, blood pressure, and fasting blood samples were obtained at local clinics. Logistic regression models were used to investigate the association of nutrient intakes with each cardiometabolic risk factor, adjusting for age, sex, physical activity, area of residence, and household income. Survey instruments, protocols, and informed consent were approved by the institutional review committee of the University of North Carolina at Chapel Hill, NC, USA; the National Institute for Nutrition and Health, Chinese Center for Disease Control and Prevention; and the China–Japan Friendship Hospital, Ministry of Health. Findings 19% of children had prehypertension and 14% had hypertension. A significant difference in high fasting glucose/glycated haemoglobin (HbA1c) concentrations (fasting glucose ≥100 mg/dL and HbA1c ≥5·7%) was reported between children from urban and rural areas (37% vs 23%; p=0·011), and between children from high-income and low-income households (30% vs 20%; p=0·047). More than 50% of participants had predyslipidemia (ie, at least one lipid measurement above borderline lipid cutoff points), and 21% of children had dyslipidemia. Logistic regression analysis—adjusted by sex, age, physical activity, area of residence, and household income—showed that higher total daily energy intake was associated with a greater likelihood of having pre-hypertension (odds ratio [OR] 1·81 [95% CI 1·03–3·18]; p=0·039), higher total sugar intake was associated with a higher likelihood of hypertension (3·59 [1·76–7·32]; p Interpretation Childhood cardiometabolic risk is prevalent in urban and rural areas of China and across different socioeconomic backgrounds, although disparities between classes still pervade. Several dietary factors, such as sugar consumption, were significant correlates of cardiometabolic risk. Nutritional education and intervention are needed to reduce sugar intake and improve the health status of Chinese children. Funding This study used data from the China Health and Nutrition Survey, which is supported by the National Institute for Nutrition and Health (China Center for Disease Control and Prevention), Carolina Population Center (the University of North Carolina at Chapel Hill), and a research grant from the US National Institutes of Health. Data analysis was funded by Nestle Research Center.

In the emission spectrum of the SbF molecule a new band system is recorded in the near infrared. The rotational analysis of these new bands shows that they belong to the b 0 + - X 2 1 and b 0 + - X 1 O + transitions and yields molecular constants for the states involved. This new information, together with improved vibrational analyses of the B and C 1 systems, permits the electronic energy diagram of the SbF molecule to be derived.