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The high overall plant-based diet index (PDI) is considered to protect against type 2 diabetes in the general population. However, whether the PDI affects gestational diabetes mellitus (GDM) risk among pregnant women is still unclear. We evaluated the association between PDI and GDM risk based on a Chinese large prospective cohort – the Tongji Maternal and Child Health Cohort. Dietary data were collected at 13–28 weeks of pregnancy by a validated semi-quantitative FFQ. The PDI was obtained by assigning plant food groups positive scores while assigning animal food groups reverse scores. GDM was diagnosed by a 75 g 2-h oral glucose tolerance test at 24–28 weeks of gestation. Logistic regression models were fitted to estimate OR of GDM, with associated 95 % CI, comparing women in different PDI quartiles. Among the total 2099 participants, 169 (8·1 %) were diagnosed with GDM. The PDI ranged from 21·0 to 52·0 with a median of 36·0 (interquartile range (IQR) 33·0–39·0). After adjusting for social-demographic characteristics and lifestyle factors etc., the participants with the highest quartile of PDI were associated with 57 % reduced odds of GDM compared with women in the lowest quartile of PDI (adjusted OR 0·43; 95 % CI 0·24, 0·77; Pfor trend = 0·005). An IQR increment in PDI was associated with 29 % decreased odds of GDM (adjusted OR 0·71; 95 % CI 0·56, 0·90). Findings suggest that adopting a plant-based diet during pregnancy could reduce GDM risk among Chinese women, which may be valuable for dietary counselling during pregnancy.
Cysticercosis caused by the metacestode larval stage of Taenia hydatigena formerly referred to as Cysticercus tenuicollis is a disease of veterinary importance that constitutes a significant threat to livestock production worldwide, especially in endemic regions due to condemnation of visceral organs and mortality rate of infected young animals. While the genetic diversity among parasites is found to be potentially useful in many areas of research including molecular diagnostics, epidemiology and control, that of T. hydatigena across the globe remains poorly understood. In this study, analysis of the mitochondrial DNA (mtDNA) of adult worms and larval stages of T. hydatigena isolated from dogs, sheep and a wild boar in China showed that the population structure consists of two major haplogroups with very high nucleotide substitutions involving synonymous and non-synonymous changes. Compared with other cestodes such as Echinococcus spp., the genetic variation observed between the haplogroups is sufficient for the assignment of major haplotype or genotype division as both groups showed a total of 166 point-mutation differences between the 12 mitochondrial protein-coding gene sequences. Preliminary analysis of a nuclear protein-coding gene (pepck) did not reveal any peculiar changes between both groups which suggests that these variants may only differ in their mitochondrial makeup.
Bile acids (BA) have emerged as signalling molecules regulating intestinal physiology. The importance of intestinal microbiota in production of secondary BA, for example, lithocholic acid (LCA) which impairs enterocyte proliferation and permeability, triggered us to determine the effects of oral probiotics on intestinal BA metabolism. Piglets were weaned at 28 d of age and allocated into control (CON, n 14) or probiotic (PRO, n 14) group fed 50 mg of Lactobacillus plantarum daily, and gut microbiota and BA profile were determined. To test the potential interaction of LCA with bacteria endotoxins in inducing damage of enterocytes, IPEC-J2 cells were treated with LCA, lipopolysaccharide (LPS) and LCA + LPS and expressions of genes related to inflammation, antioxidant capacity and nutrient transport were determined. Compared with the CON group, the PRO group showed lower total LCA level in the ileum and higher relative abundance of the Lactobacillus genus in faeces. In contrast, the relative abundances of Bacteroides, Clostridium_sensu_stricto_1, Parabacteroides and Ruminococcus_1, important bacteria genera in BA biotransformation, were all lower in the PRO than in the CON group. Moreover, PRO piglets had lower postprandial glucagon-like peptide-1 level, while higher glucose level than CON piglets. Co-administration of LPS and LCA led to down-regulated expression of glucose and peptide transporter genes in IPEC-J2 cells. Altogether, oral L. plantarum altered BA profile probably by modulating relative abundances of gut microbial genera that play key roles in BA metabolism and might consequently impact glucose homoeostasis. The detrimental effect of LCA on nutrient transport in enterocytes might be aggravated under LPS challenge.
The Chinese National Twin Registry (CNTR), initiated in 2001, has now become the largest twin registry in Asia. From 2015 to 2018, the CNTR continued to receive Chinese government funding and had recruited 61,566 twin-pairs by 2019 to study twins discordant for specific exposures such as environmental factors, and twins discordant for disease outcomes or measures of morbidity. Omic data, including genetics, genomics, metabolomics, and proteomics, and gut microbiome will be tested. The integration of omics and digital technologies in public health will advance our understanding of precision public health. This review introduces the updates of the CNTR, including study design, sample size, biobank, zygosity assessment, advances in research and future systems epidemiologic research.
The current transient was studied on AlGaN/GaN HEMTs for RF power amplifiers under different temperatures. The current transient measurements include two different approaches. One is to measure the current transient from off-state (without bias) to a quiescent point (Q-point). Different transient behaviors were observed while switching to different Q-points. Another one is to measure the current transient from different currents to the Q-point of VDS = 28 V and ID = 100 mA/mm. The different currents before switching to Q-point of VDS = 28 V and ID = 100 mA/mm show the different transient characteristics. Most of the current transient demonstrates temperature independence in this study.
Optoelectronic nanoscale devices have wide applications in chemical, biological, and medical technologies. Improving the performance efficiency of these devices remains a challenge. Performance is mainly dictated by the structure and characteristics of the semiconductor materials. Once a nanodevice is fabricated, its efficiency is determined. The key to improving efficiency is to control the interfaces in the device. In this article, we describe how the piezo-phototronic effect can be effectively utilized to modulate the band at the interface of a metal/semiconductor contact or a p–n junction to enhance the external efficiency of many optoelectronic nanoscale devices such as photodetectors, solar cells, and light-emitting diodes (LEDs). The piezo-phototronic effect can be highly effective at enhancing the efficiency of energy conversion in today’s green and renewable energy technology without using the sophisticated nanofabrication procedures that have high cost and complexity.
Third-generation semiconductors, such as ZnO and GaN, exhibit strong piezoelectric polarization due to the lack of inversion symmetry. The piezotronic effect observed in these semiconductors was proposed for tuning carrier transport in electronic devices by utilizing the induced piezoelectric potential as a virtual gate. This novel concept allows effective interactions between micro-/nanoelectronic devices and external mechanical stimuli. Piezotronics provide a promising approach for designing future electronic devices beyond Moore’s Law with potential for developing smart sensors, environment monitoring systems, human–machine interaction elements, and other transducers. In this article, we review recent progress in piezotronics using one-dimensional materials, heterojunctions, and large-scale arrays. We provide guidance for future piezotronic devices based on these materials.
This article discusses recent studies of piezotronics and piezo-phototronics of two-dimensional (2D) materials. Two-dimensional semiconductor materials have demonstrated excellent electronic and optoelectronic properties, and these ultrathin materials are candidates for next-generation devices. Among 2D semiconductors, transition-metal dichalcogenides in particular have large in-place piezoelectricity due to the noncentrosymmetry along the armchair direction. A strong coupling of piezoelectric and semiconducting properties has been reported for Schottky contacts and p–n junctions, even in single-layer materials. Since the carrier concentration of ultrathin 2D materials can be easily modulated by external piezocharges, layered composites of ferroelectric/2D materials also show promising piezotronic and piezo-phototronic properties.
Piezotronics can not only afford control of electronic transport over potential barriers, but the attendant mechanical stress can also influence various physical properties of piezoelectric semiconductors. Stress significantly affects the optical properties of these materials as well as their response toward the chemical environment and magnetic fields. This article focuses on the utilization of piezotronics with regard to these physical parameters for sensor applications. Stress sensors, optical sensors (especially in the ultraviolet range), and sensors for chemicals in gas and liquid phases or magnetic fields via coupled magnetostrictive layers are discussed. The benefits of piezotronics for sensors are highlighted by discussing respective figures of merit.