Application of biosynthesized ZnO nanoparticles on an electrochemical H 2 O 2 biosensor

ZnO nanoparticles (NPs) were synthesized via a green biochemical method using Corymbia citriodora leaf extract as a reducing and stabilizing agent. The biosynthesized ZnO NPs were characterized by SEM and XRD. An electrochemical H2O2 biosensor was fabricated by modification of a glassy carbon electrode using our proposed ZnO NPs. The electrochemical sensor showed excellent detection performance towards trace amounts of H2O2, demonstrating that it could potentially be used in clinical applications

Genomic Analyses of the Quinol Oxidases and/or Quinone Reductases Involved in Bacterial Extracellular Electron Transfer

To exchange electrons with extracellular substrates, some microorganisms employ extracellular electron transfer (EET) pathways that physically connect extracellular redox reactions to intracellular metabolic activity. These pathways are made of redox and structural proteins that work cooperatively to transfer electrons between extracellular substrates and the cytoplasmic membrane. Crucial to the bacterial and archaeal EET pathways are the quinol oxidases and/or quinone reductases in the cytoplasmic membrane where they recycle the quinone/quinol pool in the cytoplasmic membrane during EET reaction. Up to date, three different families of quinol oxidases and/or quinone reductases involved in bacterial EET have been discovered. They are the CymA, CbcL/MtrH/MtoC, and ImcH families of quinol oxidases and/or quinone reductases that are all multiheme c-type cytochromes (c-Cyts). To investigate to what extent they are distributed among microorganisms, we search the bacterial as well as archaeal genomes for the homologs of these c-Cyts. Search results reveal that the homologs of these c-Cyts are only found in the Domain Bacteria. Moreover, the CymA homologs are only found in the phylum of Proteobacteria and most of them are in the Shewanella genus. In addition to Shewanella sp., CymA homologs are also found in other Fe(III)-reducing bacteria, such as of Vibrio parahaemolyticus. In contrast to CymA, CbcL/MtrH/MtoC, and ImcH homologs are much more widespread. CbcL/MtrH/MtoC homologs are found in 15 phyla, while ImcH homologs are found in 12 phyla. Furthermore, the heme-binding motifs of CbcL/MtrH/MtoC and ImcH homologs vary greatly, ranging from 3 to 23 and 6 to 10 heme-binding motifs for CbcL/MtrH/MtoC and ImcH homologs, respectively. Moreover, CymA and CbcL/MtrH/MtoC homologs are found in both Fe(III)-reducing and Fe(II)-oxidizing bacteria, suggesting that these families of c-Cyts catalyze both quinol-oxidizing and quinone-reducing reactions. ImcH homologs are only found in the Fe(III)-reducing bacteria, implying that they are only the quinol oxidases. Finally, some bacteria have the homologs of two different families of c-Cyts, which may improve the bacterial capability to exchange electrons with extracellular substrates

Interference-Limited Ultra-Reliable and Low-Latency Communications: Graph Neural Networks or Stochastic Geometry?

In this paper, we aim to improve the Quality-of-Service (QoS) of Ultra-Reliability and Low-Latency Communications (URLLC) in interference-limited wireless networks. To obtain time diversity within the channel coherence time, we first put forward a random repetition scheme that randomizes the interference power. Then, we optimize the number of reserved slots and the number of repetitions for each packet to minimize the QoS violation probability, defined as the percentage of users that cannot achieve URLLC. We build a cascaded Random Edge Graph Neural Network (REGNN) to represent the repetition scheme and develop a model-free unsupervised learning method to train it. We analyze the QoS violation probability using stochastic geometry in a symmetric scenario and apply a model-based Exhaustive Search (ES) method to find the optimal solution. Simulation results show that in the symmetric scenario, the QoS violation probabilities achieved by the model-free learning method and the model-based ES method are nearly the same. In more general scenarios, the cascaded REGNN generalizes very well in wireless networks with different scales, network topologies, cell densities, and frequency reuse factors. It outperforms the model-based ES method in the presence of the model mismatch.Comment: Submitted to IEEE journal for possible publicatio

Application of Background Information Database in Trend Change of Agricultural Land Area of Guangxi

Abstract. Guangxi Province is one of the regions more serious desertification. This paper using ENVI image processing system, according to remote sensing image interpretation target mark and image spectral characteristics, found remote sensing interpretation model of the background information of forest, shrub and grass, agricultural land, surface water, towns, roads from TM and ETM data from 1988 to 2008, using supervision, unsupervised, maximum classification of natural law to retrieve background information from simple to complex interpretation of each classification. Meanwhile ,using humancomputer interaction to refine the results. The output shp format data Vector file of disaggregated data edited in the GIS system, and get the background information on various types of remote sensing data each time. The result showed that agricultural land area showed a decreasing trend , but change is not very significant

CXCL13/CXCR5 Axis Predicts Poor Prognosis and Promotes Progression Through PI3K/AKT/mTOR Pathway in Clear Cell Renal Cell Carcinoma

The chemokine ligands and their receptors play critical roles in cancer progression and patients outcomes. We found that CXCL13 was significantly upregulated in ccRCC tissues compared with normal tissues in both The Cancer Genome Atlas (TCGA) cohort and a validated cohort of 90 pairs ccRCC tissues. Statistical analysis showed that high CXCL13 expression related to advanced disease stage and poor prognosis in ccRCC. We also revealed that serum CXCL13 levels in ccRCC patients (n = 50) were significantly higher than in healthy controls (n = 40). Receiver operating characteristic (ROC) curve revealed that tissue and serum CXCL13 expression might be a diagnostic biomarker for ccRCC with an area under curve (AUC) of 0.809 and 0.704, respectively. CXCL13 was significantly associated with its receptor, CXCR5, in ccRCC tissues, and ccRCC patients in high CXCL13 high CXCR5 expression group have a worst prognosis. Functional and mechanistic study revealed that CXCL13 promoted the proliferation and migration of ccRCC cells by binding to CXCR5 and activated PI3K/AKT/mTOR signaling pathway. These results suggested that CXCL13/CXCR5 axis played a significant role in ccRCC and might be a therapeutic target and prognostic biomarker

BPF-oF: Storage Function Pushdown Over the Network

Storage disaggregation, wherein storage is accessed over the network, is popular because it allows applications to independently scale storage capacity and bandwidth based on dynamic application demand. However, the added network processing introduced by disaggregation can consume significant CPU resources. In many storage systems, logical storage operations (e.g., lookups, aggregations) involve a series of simple but dependent I/O access patterns. Therefore, one way to reduce the network processing overhead is to execute dependent series of I/O accesses at the remote storage server, reducing the back-and-forth communication between the storage layer and the application. We refer to this approach as \emph{remote-storage pushdown}. We present BPF-oF, a new remote-storage pushdown protocol built on top of NVMe-oF, which enables applications to safely push custom eBPF storage functions to a remote storage server. The main challenge in integrating BPF-oF with storage systems is preserving the benefits of their client-based in-memory caches. We address this challenge by designing novel caching techniques for storage pushdown, including splitting queries into separate in-memory and remote-storage phases and periodically refreshing the client cache with sampled accesses from the remote storage device. We demonstrate the utility of BPF-oF by integrating it with three storage systems, including RocksDB, a popular persistent key-value store that has no existing storage pushdown capability. We show BPF-oF provides significant speedups in all three systems when accessed over the network, for example improving RocksDB's throughput by up to 2.8$\times$ and tail latency by up to 2.6$\times$

Functional characterization of PETIOLULE-LIKE PULVINUS (PLP) gene in abscission zone development in Medicago truncatula and its application to genetic improvement of alfalfa

Alfalfa (Medicago sativa L.) is one of the most important forage crops throughout the world. Maximizing leaf retention during the haymaking process is critical for achieving superior hay quality and maintaining biomass yield. Leaf abscission process affects leaf retention. Previous studies have largely focused on the molecular mechanisms of floral organ, pedicel and seed abscission but scarcely touched on leaf and petiole abscission. This study focuses on leaf and petiole abscission in the model legume Medicago truncatula and its closely related commercial species alfalfa. By analysing the petiolule-like pulvinus (plp) mutant in M. truncatula at phenotypic level (breakstrength and shaking assays), microscopic level (scanning electron microscopy and cross-sectional analyses) and molecular level (expression level and expression pattern analyses), we discovered that the loss of function of PLP leads to an absence of abscission zone (AZ) formation and PLP plays an important role in leaflet and petiole AZ differentiation. Microarray analysis indicated that PLP affects abscission process through modulating genes involved in hormonal homeostasis, cell wall remodelling and degradation. Detailed analyses led us to propose a functional model of PLP in regulating leaflet and petiole abscission. Furthermore, we cloned the PLP gene (MsPLP) from alfalfa and produced RNAi transgenic alfalfa plants to down-regulate the endogenous MsPLP. Down-regulation of MsPLP results in altered pulvinus structure with increased leaflet breakstrength, thus offering a new approach to decrease leaf loss during alfalfa haymaking process

Reduction of Mitoferrin Results in Abnormal Development and Extended Lifespan in Caenorhabditis elegans

Iron is essential for organisms. It is mainly utilized in mitochondria for biosynthesis of iron-sulfur clusters, hemes and other cofactors. Mitoferrin 1 and mitoferrin 2, two homologues proteins belonging to the mitochondrial solute carrier family, are required for iron delivery into mitochondria. Mitoferrin 1 is highly expressed in developing erythrocytes which consume a large amount of iron during hemoglobinization. Mitoferrin 2 is ubiquitously expressed, whose functions are less known. Zebrafish with mitoferrin 1 mutation show profound hypochromic anaemia and erythroid maturation arrests, and yeast with defects in MRS3/4, the counterparts of mitoferrin 1/2, has low mitochondrial iron levels and grows poorly by iron depletion. Mitoferrin 1 expression is up-regulated in yeast and mouse models of Fiedreich's ataxia disease and in human cell culture models of Parkinson disease, suggesting its involvement in the pathogenesis of diseases with mitochondrial iron accumulation. In this study we found that reduced mitoferrin levels in C. elegans by RNAi treatment causes pleiotropic phenotypes such as small body size, reduced fecundity, slow movement and increased sensitivity to paraquat. Despite these abnormities, lifespan was increased by 50% to 80% in N2 wild type strain, and in further studies using the RNAi sensitive strain eri-1, more than doubled lifespan was observed. The pathways or mechanisms responsible for the lifespan extension and other phenotypes of mitoferrin RNAi worms are worth further study, which may contribute to our understanding of aging mechanisms and the pathogenesis of iron disorder related diseases

Critical role for Gimap5 in the survival of mouse hematopoietic stem and progenitor cells

HSCs lacking the guanosine nucleotide-binding protein Gimap5, which stabilizes expression of the Mcl-1 Bcl2 family protein, exhibit impaired survival and long-term repopulation capacity

Preparations of Meiotic Pachytene Chromosomes and Extended DNA Fibers from Cotton Suitable for Fluorescence In Situ Hybridization

Fluorescence in situ hybridization (FISH) has become one of the most important techniques applied in plant molecular cytogenetics. However, the application of this technique in cotton has lagged behind because of difficulties in chromosome preparation. The focus of this article was FISH performed not only on cotton pachytene chromosomes, but also on cotton extended DNA fibers. The cotton pollen mother cells (PMCs) instead of buds or anthers were directly digested in enzyme to completely breakdown the cell wall. Before the routine acetic acid treatment, PMCs were incubated in acetic acid and enzyme mixture to remove the cytoplasm and clear the background. The method of ice-cold Carnoy's solution spreading chromosome was adopted instead of nitrogen removed method to avoid chromosomes losing and fully stretch chromosome. With the above-improved steps, the high-quality well-differentiated pachytene chromosomes with clear background were obtained. FISH results demonstrated that a mature protocol of cotton pachytene chromosomes preparation was presented. Intact and no debris cotton nuclei were obtained by chopping from etiolation cotyledons instead of the conventional liquid nitrogen grinding method. After incubating the nuclei with nucleus lysis buffer on slide, the parallel and clear background DNA fibers were acquired along the slide. This method overcomes the twist, accumulation and fracture of DNA fibers compared with other methods. The entire process of DNA fibers preparation requires only 30 min, in contrast, it takes 3 h with routine nitrogen grinding method. The poisonous mercaptoethanol in nucleus lysis buffer is replaced by nonpoisonous dithiothreitol. PVP40 in nucleus isolation buffer is used to prevent oxidation. The probability of success in isolating nuclei for DNA fiber preparation is almost 100% tested with this method in cotton. So a rapid, safe, and efficient method for the preparation of cotton extended DNA fibers suitable for FISH was established