This paper describes an ultra-low power SAR ADC for medical implant devices. To achieve the nano-watt range power consumption, an ultra-low power design strategy has been utilized, imposing maximum ...simplicity on the ADC architecture, low transistor count and matched capacitive DAC with a switching scheme which results in full-range sampling without switch bootstrapping and extra reset voltage. Furthermore, a dual-supply voltage scheme allows the SAR logic to operate at 0.4 V, reducing the overall power consumption of the ADC by 15% without any loss in performance. The ADC was fabricated in 0.13- mu m CMOS. In dual-supply mode (1.0 V for analog and 0.4 V for digital), the ADC consumes 53 nW at a sampling rate of 1 kS/s and achieves the ENOB of 9.1 bits. The leakage power constitutes 25% of the 53-nW total power.
Ascorbic acid (AA), as one of the most important vitamins, participates in various physiological reactions in the human body and is implicated with many diseases. Therefore, the development of ...effective methods for monitoring the AA level in living systems is of great significance. Up to date, various technologies have been developed for the detection of AA. However, few methods can realize the direct detection of endogenous AA in living cells. In this work, we for the first time reported that near-infrared (NIR) graphene quantum dots (GQD) possessed good two-photon fluorescence properties with a NIR emission at 660 nm upon exciting with 810 nm femtosecond pulses and a two-photon (TP) excitation action cross-section (δΦ) of 25.12 GM. They were then employed to construct a TP nanoprobe for detection and bioimaging of endogenous AA in living cells. In this nanosystem, NIR GQDs (NGs), which exhibited lower fluorescence background in living system to afford improved fluorescence imaging resolution, were acted as fluorescence reporters. Also CoOOH nanoflakes were chosen as fluorescence quenchers by forming on the surface of NGs. Once AA was introduced, CoOOH was reduced to Co2+, which resulted in a “turn-on” fluorescence signal of NGs. The proposed nanoprobe demonstrated high sensitivity toward AA, with the observed LOD of 270 nM. It also showed high selectivity to AA with excellent photostability. Moreover, the nanoprobe was successfully used for TP imaging of endogenous AA in living cells as well as deep tissue imaging.
Integrating a molecular catalyst with a light harvester into a photocatalyst is an effective strategy for solar light conversion. However, it is challenging to establish a crystallized framework with ...well‐organized connections that favour charge separation and transfer. Herein, we report the heterogenization of a Salen metal complex molecular catalyst into a rigid covalent organic framework (COF) through covalent linkage with the light‐harvesting unit of pyrene for photocatalytic hydrogen evolution. The chemically conjugated bonds between the two units contribute to fast photogenerated electron transfer and thereby promote the proton reduction reaction. The Salen cobalt‐based COF showed the best hydrogen evolution activity (1378 μmol g−1 h−1), which is superior to the previously reported nonnoble metal based COF photocatalysts. This work provides a strategy to construct atom‐efficient photocatalysts by the heterogenization of molecular catalysts into covalent organic frameworks.
The heterogenization of a Salen metal complex molecular catalyst into a rigid covalent organic framework (COF) through covalent linkage with the light‐harvesting unit of pyrene for photocatalytic hydrogen evolution is reported. Co/Zn‐Salen‐COF showed the best hydrogen evolution activity (1378 μmol g−1 h−1), which is superior to the previously reported non‐noble metal‐based COF photocatalysts
Numerous single nucleotide polymorphisms (SNPs) associated with complex diseases have been identified by genome-wide association studies (GWAS) and expression quantitative trait loci (eQTLs) studies. ...However, few of these SNPs have explicit biological functions. Recent studies indicated that the SNPs within the 3'UTR regions of susceptibility genes could affect complex traits/diseases by affecting the function of miRNAs. These 3'UTR SNPs are functional candidates and therefore of interest to GWAS and eQTL researchers.
We developed a publicly available online database, MirSNP (http://cmbi.bjmu.edu.cn/mirsnp), which is a collection of human SNPs in predicted miRNA-mRNA binding sites. We identified 414,510 SNPs that might affect miRNA-mRNA binding. Annotations were added to these SNPs to predict whether a SNP within the target site would decrease/break or enhance/create an miRNA-mRNA binding site. By applying MirSNP database to three brain eQTL data sets, we identified four unreported SNPs (rs3087822, rs13042, rs1058381, and rs1058398), which might affect miRNA binding and thus affect the expression of their host genes in the brain. We also applied the MirSNP database to our GWAS for schizophrenia: seven predicted miRNA-related SNPs (p < 0.0001) were found in the schizophrenia GWAS. Our findings identified the possible functions of these SNP loci, and provide the basis for subsequent functional research.
MirSNP could identify the putative miRNA-related SNPs from GWAS and eQTLs researches and provide the direction for subsequent functional researches.
Statistical data on the incidence, mortality, and burden of breast cancer and the relevant risk factors are valuable for policy-making. We aimed to estimate breast cancer incidence, deaths, and ...disability-adjusted life years (DALYs) by country, gender, age group, and social-demographic status between 1990 and 2017.
We extracted breast cancer data from the 2017 Global Burden of Disease (GBD) study from 1990 through 2017 in 195 countries and territories. Data about the number of breast cancer incident cases, deaths, DALYs, and the age-standardized rates were collected. We also estimated the risk factors attributable to breast cancer deaths and DALYs using the comparative risk assessment framework of the GBD study.
In 2017, the global incidence of breast cancer increased to 1,960,681 cases. The high social-development index (SDI) quintile included the highest number of breast cancer death cases. Between 2007 and 2017, the ASDR of breast cancer declined globally, especially in high SDI and high middle SDI countries. The related DALYs were 17,708,600 in 2017 with high middle SDI quintile as the highest contributor. Of the deaths and DALYs, alcohol use was the greatest contributor in most GBD regions and other contributors included high body mass index (BMI) and high fasting plasma glucose.
The increasing global breast cancer burden is mainly observed in lower SDI countries; in higher SDI countries, the breast cancer burden tends to be relieving. Therefore, steps against attributable risk factors should be taken to reduce breast cancer burden in lower SDI countries.
Sinosenecio B. Nordenstam (Asteraceae) currently comprises 44 species. To investigate the interspecific relationship, several chloroplast markers, including ndhC-trnV, rpl32-trnL, matK, and rbcL, are ...used to analyze the phylogeny of Sinosenecio. However, the chloroplast genomes of this genus have not been thoroughly investigated. We sequenced and assembled the Sinosenecio albonervius chloroplast genome for the first time. A detailed comparative analysis was performed in this study using the previously reported chloroplast genomes of three Sinosenecio species. The results showed that the chloroplast genomes of four Sinosenecio species exhibit a typical quadripartite structure. There are equal numbers of total genes, protein-coding genes and RNA genes among the annotated genomes. Per genome, 49-56 simple sequence repeats and 99 repeat sequences were identified. Thirty codons were identified as RSCU values greater than 1 in the chloroplast genome of S. albonervius based on 54 protein-coding genes, indicating that they showed biased usage. Among 18 protein-coding genes, 46 potential RNA editing sites were discovered. By comparing these chloroplast genomes' structures, inverted repeat regions and coding regions were more conserved than single-copy and non-coding regions. The junctions among inverted repeat and single-copy regions showed slight difference. Several hot spots of genomic divergence were detected, which can be used as new DNA barcodes for species identification. Phylogenetic analysis of the whole chloroplast genome showed that the four Sinosenecio species have close interspecific relationships. The complete chloroplast genome of Sinosenecio albonervius was revealed in this study, which included a comparison of Sinosenecio chloroplast genome structure, variation, and phylogenetic analysis for related species. These will help future research on Sinosenecio taxonomy, identification, origin, and evolution to some extent.
This brief describes a 14-b 10-kS/s successive approximation register analog-to-digital converter (ADC) for biomedical applications. In order to achieve enhanced linearity, a uniform-geometry ...nonbinary-weighted capacitive digital-to-analog converter is implemented. In addition, a secondary-bit approach to dynamically shift decision levels for error correction is employed. To reduce the power consumption, the ADC also features a power-optimized comparator with bias control. Prototyped in a 65-nm CMOS process, the ADC consumes 1.98 μW and provides an effective number of bit (ENOB) of 12.5 bat 0.8 V while occupying an active area of 0.28 mm 2 .
ZnO is a promising high-temperature thermoelectric material because of its non-toxicity and low-cost. However, the wide band gap and low electrical conductivity lead to inferior thermoelectric ...properties. Herein, C-doping in ZnO bulk was achieved by the pyrolysis of hydrothermal surfactant TEA through a facile and speedy SPS technique. DFT calculation and experimental results show that C was incorporated into the O-site in ZnO, which reduces band gap and increases carrier concentration, thereby improving electrical conductivity and power factor. Meanwhile, the additional point defects introduced by the substitution of C/O atoms strengthen phonon scattering and decrease thermal conductivity. Benefiting from C-doping via not only tuning the electrical transport properties but also reducing the thermal conductivity, a peak ZT value of 0.024 at 773 K was achieved for Zn(O,C) bulk. It indicates that C-doping in ZnO is an effective and convenient strategy to improve thermoelectric performance.
Coronary heart disease is a major cause of death and disability in developed countries. Stent implantation has become an efficacious treatment for a culprit lesion vessel of the coronary artery. ...However, 10%–20% restenosis is still an important complication that restricts the clinical safety and efficacy of drug-eluting stents. In-stent restenosis may lead to the recurrence of major cardiovascular adverse events, including angina pectoris, acute myocardial infarction, and even sudden cardiac death. These events are currently serious problems that occur after coronary stent implantation. Clinical physicians face a difficult choice for in-stent restenosis treatment. Recent studies indicate that a drug-coated balloon has promising clinical efficacy similar to the drug-eluting stents for treating coronary in-stent restenosis. Therefore, in this study, we highlight the progress of coronary intervention and the use of drug-coated balloons in the treatment of in-stent restenosis (ISR).