Production of Nitrogen-Doped Graphene by Low-Energy Nitrogen Implantation

Nitrogen doping of graphene is a suitable route to tune the electronic structure of graphene, leading to <i>n</i>-type conductive materials. Herein, we report a simple way to insert nitrogen atoms into graphene by low-energy nitrogen bombardment, forming nitrogen-doped graphene. The formation of nitrogen-doped graphene is investigated with high resolution X-ray photoelectron spectroscopy, allowing to determine the doping level and to identify two different carbon–nitrogen species. By application of different ion implantation energies and times, we demonstrate that a doping level of up to 0.05 monolayers is achievable and that the branching ratio of the two nitrogen species can be varied

Lu_et_al_datamatrix

Data matrix of Qingmenodu

An optical fibre-based sensor for real-time monitoring of clinical linear accelerator radiotherapy delivery

A novel real-time optical fibre X-Ray dosimeter for monitoring the radiation pulses delivered from a clinical linear accelerator (Linac) is presented. The primary focus of the sensor is to measure low doses of ionising X-ray radiation in real time (limited to 0.1-ms gate time of the detector). The sensor tip material scintillates upon exposure to X-ray energy and the resultant low-level visible light signal is coupled to a polymethyl methacrylate plastic optical fibre, which is used to guide it towards a distal avalanche photodiode-based detector. The detector measures the low-level scintillating light from the sensor, thereby converting the ionizing radiation energy to a measurable signal with a time resolution of 0.1 ms. Results show that the scintillating optical fibre X-ray dosimeter is capable of capturing the individual X-Ray pulses delivered by the Linac during normal operation. Further examination of the results demonstrates that the sensor is capable of measuring dose rate and, hence, dose with a linearity (R-2 = 0.9995 - 0.9999) and in a highly repeatable manner for dose rates in the range 100 to 600 monitor units/min

Detection of premature browning in ground beef with an integrated optical-fibre based sensor using reflection spectroscopy and fibre Bragg grating technology

This paper reports on an optical fibre based sensor system to detect the occurrence of premature browning in ground beef. Premature browning (PMB) occurs when, at a temperature below the pasteurisation temperature of 71°C, there are no traces of pink meat left in the patty. PMB is more frequent if poorer quality beef or beef that has been stored under imperfect conditions. The experimental work pertaining to this paper involved cooking fresh meat and meat that has been stored in a freezer for, 1 week, 1 month and 3 months and recording the reflected spectra and temperature at the core of the product, during the cooking process, in order to develop a classifier based on the spectral response and using a Self-Organising Map (SOM) to classify the patties into one of four categories, based on their colour. Further tests were also carried out on developing an all-optical fibre sensor for measuring both the temperature and colour in a single integrated probe. The integrated probe contains two different sensor concepts, one to monitor temperature, based on Fibre Bragg Grating (FBG) technology and a second for meat quality, based on reflection spectroscopy in the visible wavelength range

Transcriptome profiling to identify key mediators of granulosa cell proliferation upon FSH stimulation in the goose (<i>Anser cygnoides</i>)

<p>1. The low reproductive performance of geese has seriously hampered the development of the industry. Reproductive performance, particularly the egg laying rate mainly depends on the development of the follicle. Previous studies have shown that follicle-stimulating hormone (FSH) plays an important role in the process of follicular development, but the exact underlying mechanism remains unclear.</p> <p>2. This study showed that FSH stimulated granulosa cell proliferation in a dose-dependent manner. The effect of FSH treatment on granulosa cell proliferation was greatest at a dose of 100 mIU/ml FSH for 24 h.</p> <p>3. Secondly, the effect of different concentrations of FSH on goose granulosa cell proliferation was investigated, and <i>de novo</i> transcriptome assembly and gene expression analysis performed using short-read sequencing technology (Illumina). High-throughput sequencing results yielded 62.61 M reads and 7.8 G base pairs from granulosa cells treated with 100 mIU/ml FSH. These reads were assembled into 65,757 unigenes (mean length: 705 bp) with an N50 of 903 bp. A total of 110 upregulated and 510 downregulated differentially expressed genes (DEGs) were identified by RNA-seq.</p> <p>4. Functional analysis by gene ontology (GO) and KEGG pathway annotation indicated that hormone biosynthesis (GO:0042446), positive regulation of hormone secretion (GO:0046887), steroid biosynthesis, oxidative phosphorylation and carbon metabolism pathways were involved in FSH-mediated proliferation of goose granulosa cells.</p> <p>5. After screening, a group of key responsive genes including superoxide dismutase 1, fatty acyl-CoA reductase 1, transforming growth factor-beta receptor-associated protein 1 and follistatin were tested by real-time reverse transcription PCR to confirm differential expression in granulosa cells stimulated by FSH.</p> <p>6. FSH-stimulated goose granulosa cells and DEG profiling data provided comprehensive gene expression information at the transcriptional level that could promote better understanding of the molecular mechanisms underlying follicle development in response to FSH stimulation.</p

Molecular cloning and functional analysis of the goose <i>FSHβ</i> gene

<div><p></p><p> </p><p></p><p></p><p>The objective of this investigation was to clone goose <i>FSH</i>β-subunit cDNA and to construct a <i>FSH</i> fusion gene to identify the function of <i>FSHβ</i> mRNA during stages of the breeding cycle.</p><p></p><p></p><p>The <i>FSHβ</i> gene was obtained by reverse transcription-PCR, and the full-length <i>FSHβ</i> mRNA sequence was amplified by rapid-amplification of cDNA ends. <i>FSHβ</i> mRNA expression was detected in reproductive tissues at different stages (pre-laying, laying period, and broody period). Additionally, the expression of 4 genes known to be involved in reproduction (<i>FSHβ, GnRH, GH</i>, and <i>BMP</i>) were evaluated in COS-7 cells expressing the fusion gene (<i>pVITRO2-FSHαβ-CTP</i>).</p><p></p><p></p><p>The results show that the <i>FSHβ</i> gene consists of a 16 base pair (bp) 5′-untranslated region (UTR), 396 bp open reading frame, and alternative 3′-UTRs at 518 bp and 780 bp, respectively. qPCR analyses revealed that <i>FSHβ</i> mRNA is highly transcribed in reproductive tissues, including the pituitary, hypothalamus, ovaries, and oviduct. <i>FSHβ</i> mRNA expression increased and subsequently decreased in the pituitary, ovaries, and oviduct during the reproductive stages. Stable FSH expression was confirmed using enzyme-linked immunosorbent assays after transfection with the <i>pVITRO2-FSHαβ-CTP</i> plasmid. <i>FSHβ, GnRH</i>, and <i>BMP</i> expression increased significantly 36 h and 48 h after transfection with the fusion gene in COS-7 cells.</p><p></p><p></p><p>The results demonstrate that the <i>FSHβ</i> subunit functions in the goose reproductive cycle and provides a theoretical basis for future breeding work.</p><p></p><p></p><p></p></div

Trans-ancestry meta-analyses identify rare and common variants associated with blood pressure and hypertension

High blood pressure is a major risk factor for cardiovascular disease and premature death. However, there is limited knowledge on specific causal genes and pathways. To better understand the genetics of blood pressure, we genotyped 242,296 rare, low-frequency and common genetic variants in up to 192,763 individuals and used ∼155,063 samples for independent replication. We identified 30 new blood pressure- or hypertension-associated genetic regions in the general population, including 3 rare missense variants in RBM47, COL21A1 and RRAS with larger effects (>1.5 mm Hg/allele) than common variants. Multiple rare nonsense and missense variant associations were found in A2ML1, and a low-frequency nonsense variant in ENPEP was identified. Our data extend the spectrum of allelic variation underlying blood pressure traits and hypertension, provide new insights into the pathophysiology of hypertension and indicate new targets for clinical intervention

The genetics of blood pressure regulation and its target organs from association studies in 342,415 individuals.

To dissect the genetic architecture of blood pressure and assess effects on target organ damage, we analyzed 128,272 SNPs from targeted and genome-wide arrays in 201,529 individuals of European ancestry, and genotypes from an additional 140,886 individuals were used for validation. We identified 66 blood pressure-associated loci, of which 17 were new; 15 harbored multiple distinct association signals. The 66 index SNPs were enriched for cis-regulatory elements, particularly in vascular endothelial cells, consistent with a primary role in blood pressure control through modulation of vascular tone across multiple tissues. The 66 index SNPs combined in a risk score showed comparable effects in 64,421 individuals of non-European descent. The 66-SNP blood pressure risk score was significantly associated with target organ damage in multiple tissues but with minor effects in the kidney. Our findings expand current knowledge of blood pressure-related pathways and highlight tissues beyond the classical renal system in blood pressure regulation

Rare and low-frequency coding variants alter human adult heigh

Height is a highly heritable, classic polygenic trait with approximately 700 common associated variants identified through genome-wide association studies so far. Here, we report 83 height-associated coding variants with lower minor-allele frequencies (in the range of 0.1-4.8%) and effects of up to 2 centimetres per allele (such as those in IHH, STC2, AR and CRISPLD2), greater than ten times the average effect of common variants. In functional follow-up studies, rare height-increasing alleles of STC2 (giving an increase of 1-2 centimetres per allele) compromised proteolytic inhibition of PAPP-A and increased cleavage of IGFBP-4 in vitro, resulting in higher bioavailability of insulin-like growth factors. These 83 height-associated variants overlap genes that are mutated in monogenic growth disorders and highlight new biological candidates (such as ADAMTS3, IL11RA and NOX4) and pathways (such as proteoglycan and glycosaminoglycan synthesis) involved in growth. Our results demonstrate that sufficiently large sample sizes can uncover rare and low-frequency variants of moderate-to-large effect associated with polygenic human phenotypes, and that these variants implicate relevant genes and pathways