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Background: The Pearl River and its estuary are highly exposed to anthropogenic disturbance. Because bacterial communities play an indispensable role in aquatic ecosystems, there has been an increased research focus on the statuses of these communities under human-induced perturbations. Methods and results: This study investigated the composition, diversity, and structure of bacterial communities across 29 sites from the Guangzhou section of the Pearl River (GZ) to the Pearl River Estuary (PRE) using 16S rRNA gene amplicons. The results revealed similar dominant phyla of bacteria in both GZ and PRE, as well as significant differences in bacterial community composition and diversity between the two sections. Proteobacteria and Cyanobacteria were identified as the primary drivers of compositional differences between GZ and PRE. The Cyanobacteria Dolichospermum_NIES41 and Cuspidothrix issatschenkoi were only present in GZ, whereas the marine Gram-negative bacteria of Porticoccus litoralis and Thalassolituus oleivorans were unique to PRE. Conclusions: Bacterial community composition and diversity exhibit both similarities and differences between GZ and PRE; Proteobacteria and Cyanobacteria are key factors underlying these variations. Bacterial communities in both GZ and PRE are strongly influenced by human activities, and salinity is an important factor in controlling their differences. This study provides a comprehensive analysis of the bacterial communities in GZ and PRE, establishing a foundation for better management of aquatic ecosystems impacted by anthropogenic activities. [ABSTRACT FROM AUTHOR]

The past two decades has witnessed a remarkable increase in the number of microbial genomes retrieved from marine systems1,2. However, it has remained challenging to translate this marine genomic diversity into biotechnological and biomedical applications3,4. Here we recovered 43,191 bacterial and archaeal genomes from publicly available marine metagenomes, encompassing a wide range of diversity with 138 distinct phyla, redefining the upper limit of marine bacterial genome size and revealing complex trade-offs between the occurrence of CRISPR–Cas systems and antibiotic resistance genes. In silico bioprospecting of these marine genomes led to the discovery of a novel CRISPR–Cas9 system, ten antimicrobial peptides, and three enzymes that degrade polyethylene terephthalate. In vitro experiments confirmed their effectiveness and efficacy. This work provides evidence that global-scale sequencing initiatives advance our understanding of how microbial diversity has evolved in the oceans and is maintained, and demonstrates how such initiatives can be sustainably exploited to advance biotechnology and biomedicine.Analysis of 43,191 genomes obtained from publicly available marine bacterial and archaeal metagenome data provides insights into marine bacterial evolution, CRISPR–Cas defence and antibiotic resistance genes, and demonstrates the potential of marine metagenomes for biotechnological applications. [ABSTRACT FROM AUTHOR]

With climate change and anthropic influence on the coastal ecosystems, mangrove ecosystems are disappearing at an alarming rate. Accordingly, it becomes important to track, study, record and store the mangrove microbial community considering their ecological importance and potential for biotechnological applications. Here, we provide information on mangrove fungal community composition and diversity in mangrove ecosystems with different plant species and from various locations differing in relation to anthropic influences. We describe twelve newly assembled genomes, including four chromosomal-level genomes of fungal isolates from the mangrove ecosystems coupled with functional annotations. We envisage that these data will be of value for future studies including comparative genome analysis and large-scale temporal and/or spatial research to elucidate the potential mechanisms by which mangrove fungal communities assemble and evolve. We further anticipate that the genomes represent valuable resources for bioprospecting related to industrial or clinical uses. [ABSTRACT FROM AUTHOR]

Traditional intercity passenger transportation is inefficient, inflexible, and financially unrewarding, failing to meet the demands of intercity travel. To address these issues, this study utilizes historical carpooling order data, extracts travel patterns, and devises a comprehensive plan for intercity customized passenger transport services. Firstly, a formalized description of issues related to long-distance cross-city travel, multiple lines, and scheduling around highway entry and exit points is addressed. Secondly, a single-objective integer linear programming model is constructed, aimed at maximizing the total profit for the operating company. Finally, from a spatial-temporal network perspective, a refined balanced iterative reducing and clustering using hierarchies (BIRCH) algorithm is designed for alternative station selection. To achieve a rapid and effective solution to the model, the approach is combined with a variable neighborhood search algorithm. Experimental results on historical carpooling data from Anxi County and Xiamen City demonstrate that the proposed algorithm, compared to the combination of BIRCH and genetic algorithms, exhibits shorter computation time, higher quality, and stability. Additionally, various parameter analysis and sensitivity experiments demonstrate the effectiveness of parameters used. [ABSTRACT FROM AUTHOR]

Data imbalance is a critical factor that adversely affects the performance of machine learning algorithms. It leads to deviations in decision boundaries, resulting in biased predictions towards the majority class and inaccurate classification of the minority class. Although oversampling the minority class using deep generative models is a popular strategy, many existing methods focus solely on enhancing data for the minority class while overlooking the distribution relationship within and between classes. Therefore, we propose an oversampling method that merges unsupervised clustering and generative adversarial network (GAN) to facilitate the imbalanced tabular data learning. First, we perform preprocessing (clustering) on the original data, remove clusters that do not require sampling and generate more samples for sparsely distributed minority class clusters to achieve sample balance within the minority class. Moreover, we design a CTGAN-based auxiliary classifier GAN (ACCTGAN) to generate the minority class. It enhances the semantic integrity of the synthetic data and avoids generating noisy samples. We conducted validation experiments comparing our approach to 7 typical methods on 12 real tabular datasets. Our method shows excellent performance in F1-measure and area under the curve (AUC), obtaining 19 and 20 best results on the three classifiers, respectively. It significantly enhances classification results and demonstrates good robustness and stability. [ABSTRACT FROM AUTHOR]

Deep learning (DL) techniques have recently attracted considerable attention in the field of seismic data denoising. However, most DL-based seismic denoising models require a considerable number of paired noisy–clean samples for training, which limits their application in practice. In this paper, a novel self-supervised DL scheme for noise attenuation in reflection seismic data is proposed based on the Neighbor2Neighbor strategy. The proposed method adopts a U-shaped convolutional network as the main network and incorporates regularization loss during training to improve the stability of network training, thereby constructing an end-to-end self-learning process for seismic data denoising. Specifically, a neighborhood subsampling workflow is built on single noisy seismic data to generate paired noisy images for training. Next, an unsupervised evaluation metric, grounded solely in noisy data, is adopted to quantitatively evaluate the performance of the denoising algorithm without labeled data. The application to synthetic datasets suggests that the proposed method achieves better denoising results than traditional (e.g., f−x deconvolution and wavelet analysis) and self-supervised methods, and rivals a widely used supervised DL model, the denoising convolution neural network. In real application to seismic data denoising without noise-free labels, the proposed method more effectively suppresses migration artifacts and random noise while better preserving the signal integrity compared to other methods. These improvements demonstrate that the proposed method is an independent, novel, and powerful data-driven DL scheme suitable for real seismic data denoising. [ABSTRACT FROM AUTHOR]

Studies show that machine learning models trained from biased data can discriminate against groups with certain sensitive attributes. This problem can be mitigated by cleaning the original data or learning fair representations. However, collecting real data in real-life is extremely time and resource-consuming, whereas generative models (e.g., GANs) can create new data that enable more application scenarios. Therefore, utilizing fair data generated by generative models can benefit various downstream tasks. In this paper, we propose a information-minimizing generative adversarial network to improve the fairness of machine learning by generating fair data. An ANOVA-based latent factor is constructed in the input for reducing the accuracy loss, and the joint adversarial training between the generator and classifier can better solve the indirect discrimination and achieve fair classification. Extensive experiments on various environments show the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Rhamnolipid congeners have been widely used in agriculture and biomedicine as potent surfactants. They have recently attracted attention due to their diverse and versatile biological functions, which include an important bacterial virulence factor that makes them attractive targets for research into biosynthetic pathways and gene regulation. The intricate gene expression and regulation network controlling their biosynthesis remain to be completely understood. This article summarizes current knowledge about the biosynthesis pathways and regulatory mechanisms of rhamnolipid congeners, that meet the pharmacological needs of human health and agriculture. [ABSTRACT FROM AUTHOR]

This chemical study reports a novel siderophore-like compound, β-cyclopiazonic acid (1, β-CPA) extracted from marine fungus Aspergillus flavus. The chemical structure of β-CPA was elucidated by a combination of extensive spectroscopic analyses and TDDFT-ECD calculations. The iron-binding ability and CAS assays demonstrate that β-CPA is a novel siderophore that features a different chemical structure from those of traditional siderophores. The β-CPA has no obvious influence on the growth of bacterium Pseudomonas aeruginosa PAO1. However, its iron chelator could promote the growth of P. aeruginosa PAO1, suggesting that P. aeruginosa employed siderophores to sequester iron, which is vital for their survival. The study provides the physiochemical evaluation of β-CPA, an unusual skeleton-structure siderophore, which for the first time, was proven to have the ability to bind iron and affect P. aeruginosa growth. This new discovery of siderophore provides an opportunity for developing novel anti-P. aeruginosa drugs. [ABSTRACT FROM AUTHOR]

Culture-independent metagenomic studies have revolutionized our understanding of the gut microbiota. However, the lack of full genomes from cultured species is still a limitation for in-depth studies of the gut microbiota. Here we present a substantially expanded version of our Cultivated Genome Reference (CGR), termed CGR2, providing 3324 high-quality draft genomes from isolates selected from a large-scale cultivation of bacterial isolates from fecal samples of healthy Chinese individuals. The CGR2 classifies 527 species (179 previously unidentified species) from 8 phyla, and uncovers a genomic and functional diversity of Collinsella aerofaciens. The CGR2 genomes match 126 metagenome-assembled genomes without cultured representatives in the Unified Human Gastrointestinal Genome (UHGG) collection and harbor 3767 unidentified secondary metabolite biosynthetic gene clusters, providing a source of natural compounds with pharmaceutical potentials. We uncover accurate phage–bacterium linkages providing information on the evolutionary characteristics of interaction between bacteriophages and bacteria at the strain level. Here, the authors present an expanded version of the Cultivated Genome Reference (CGR), termed CGR2, a catalog that includes 3324 high-quality draft genomes based on gut bacterial isolates from Chinese individuals, and classifies 527 species from 8 phyla, including 179 previously unidentified species, and provides information of secondary metabolite biosynthetic gene clusters and gut phage-bacteria interactions. [ABSTRACT FROM AUTHOR]

A sulfated galactofucan designated as UpG was obtained from the brown algae Undaria pinnatifida by calcium chloride extraction. Chemical analyses showed that UpG is composed of galactose and fucose at a high sulfation level. Low-molecular weight UpGP-0.5 was prepared from UpG through acid hydrolysis for structure characterization. The backbones of UpG are determined to be α-(1,3)-Fuc, α-(1,4)-Gal, α-(1,3)-Gal, and α-(1,6)-Gal by GC-MS, FT-IR, NMR, and LC-MS analyses. Sulfate groups are modified at C2 and/or C4 of fucose and C3 and/or C4 of galactose. UpG could partially lower blood sugar and serum lipid levels in type 2 diabetic mice. Moreover, UpG treatment regulates the abundance of some specific gut microbiota, such as enriching the abundance of Muribaculum and Christensenellaceae, and reducing that of Bilophila, Tannerellaceae, Candidatus Saccharimonas and Anaerotruncus. The findings characterized the detailed structure of a sulfated galactofucan and investigated its potential for the treatment of type 2 diabetes mellitus. [ABSTRACT FROM AUTHOR]

Background: Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. It is unlikely that there will ever be a single cure for cancer, but the development of molecular biology and cell biology has brought new options for cancer treatment. Our research group found in the preliminary experiments that AAs exhibited significant anti-tumor activity. Studies also showed that AAs exhibited varying degrees of downregulation effects on the expression of the NDUFV2 gene in the MCF-7/ADR and SMMC-7721/ADR cell lines. However, there is no relevant report on the role of this gene expression during the growth process of drug-resistant tumor cells. To address possible objections, this paper aims to investigate the effect of NDUFV2 gene silencing on the proliferation of the MCF-7/ADR and SMMC-7721/ADR cell lines. Results: The interfering plasmids pPLK/GFP+Puro-NDUFV2 shRNA-3 and shRNA-2 inhibited the NDUFV2 gene and protein expression most significantly in MCF-7/ADR and SMMC-7721/ADR cells, respectively. NDUFV2 gene silencing could effectively inhibit the proliferation of both cell lines. The inhibition rates for MCF-7/ADR were 67.31%, 73.02%, and 69.76% at 24 h, 48 h, and 72 h, while that for SMMC-7721/ADR were 68.89%, 71.97%, and 74.40% at 24 h, 48 h, and 72 h, respectively. The inhibition rate of SMMC-7721/ADR cell proliferation was positively correlated with time. Conclusions: Interference with the NDUFV2 gene may significantly inhibit the proliferation of MCF-7/ADR and SMMC-7721/ADR cells. This study is the pioneer to investigate that the NDUFV2 gene has been associated with the activity of inhibiting tumor cell proliferation, suggesting that the NDUFV2 gene may become a potential target for the study of tumor genesis and the development of antineoplastic drugs. [ABSTRACT FROM AUTHOR]

As a newly described Sillaginidae species, Chinese sillago (Sillago sinica) needs a better understanding of gene annotation information. In this study, we reported the first full-length transcriptome data of S. sinica using the PacBio isoform sequencing Iso-seq and a description of transcriptome structure analysis. A total of 454,979 high-quality full-length transcripts were obtained by single-molecule real-time (SMRT) sequencing, which was corrected by Illumina sequencing data. After that, 66,948 non-redundant full-length transcripts were generated after mapping to the reference genome of S. sinica, including 49 fusion isoforms and 9,250 novel isoforms. 63,459 isoforms were successfully annotated by one of the Nr, Nt, SwissProt, Pfam, KOG, GO, and KEGG databases. Additionally, 30,987 alternative polyadenylation (APA) sites, 451,867 alternative splicing (AS) events, 21,928 long non-coding RNAs (lncRNAs) and 12,911 transcription factors (TFs) were identified. The full-length transcripts of S. sinica would provide a precious resource for characterizing the transcriptome of S. sinica and for the further study of gene function and regulatory mechanism of this species. [ABSTRACT FROM AUTHOR]

Autophagy dysfunction contributes to CD4 + T cell apoptosis during sepsis leading to impairment of adaptive immunity. However, the underlying mechanism is unclear. The mammalian target of rapamycin (mTOR) pathway modulates CD4 + T cell survival during sepsis through mechanisms that are not fully understood. We developed a mouse model of sepsis through cecal ligation and puncture (CLP) to investigate dynamic changes in autophagy in CD4 + T cells. We used T cell specific-mTOR/tuberous sclerosis complex 1 (TSC1)-knockout mice to explore the roles of the mTOR pathway in modulating autophagy during sepsis. We observed reduced fusion of autophagosomes with lysosomes in the CD4 + T cells of CLP mice, which may represent a characteristic feature of autophagy dysfunction. Deletion of mTOR relieved autophagosome-lysosome fusion dysfunction and ameliorated apoptosis of CD4 + T cells in CLP mice, but this rescued phenotype was abolished by treatment with bafilomycin A1, a specific A-L fusion inhibitor. We further explored the underlying molecular mechanism and found that phosphorylation levels of transcription factor EB were significant higher in CLP mice and that expression of A-L fusion protein SNAREs were restricted, both of which were ameliorated by mTOR deletion. Taken together, these results suggest that the mTOR pathway plays a critical role in regulation of CD4 + T-cell apoptosis during sepsis, partly through regulation of A-L fusion-related protein transcription. [ABSTRACT FROM AUTHOR]

At present, the research work of dimension reduction at home and abroad is more about the theoretical exploration and application research of specific dimension reduction methods, and the research on the basic theory of dimension reduction and the spatial properties of high-dimensional data is not perfect. To solve the problem of the application of dimension reduction technology optimization in data visualization, a method of ISOMAP algorithm using Artificial Intelligence is proposed. The specific content of this method uses nonlinear Sammon mapping with short edge first preservation, to improve the "over-clustering" phenomenon of ISOMAP algorithm. When visualizing such data using Artificial Intelligence techniques, furthermore, the application scope of ISOMAP algorithm is extended to a certain extent. The experimental results show that the nonlinear Sammon mapping is sensitive to the initial value and the learning rate, to this end, we use the classical MDs (Molecular dynamics) algorithm to provide a relatively good initial value for the Sammon mapping, we choose three different neighborhood sizes: K = 8, K = 12 and K = 16. K = 8 is appropriate, while K = 12 and K = 16 are inappropriate, this can be verified by the corresponding residual, and the variable substitution method without learning rate is adopted to replace the gradient descent method which is more sensitive to the learning rate. It is proved that the application of nonlinear dimension reduction technology optimization in data visualization has been greatly improved. [ABSTRACT FROM AUTHOR]

Purpose: Inulin is a type of fermentable dietary fiber, which is non-digestible, and can improve metabolic function by modulating intestinal microbiota. This study aimed to evaluate the role of inulin in hyperuricemia and microbial composition of the gut microbiota in a mouse model of hyperuricemia established through knockout of Uox (urate oxidase) gene. Methods: KO (Uox -knockout) and WT (wild-type) mice were given inulin or saline by gavage for 7 weeks. The effect of inulin to combat hyperuricemia was determined by assessing the changes in serum UA (uric acid) levels, inflammatory parameters, epithelial barrier integrity, fecal microbiota alterations, and SCFA (short-chain fatty acid) concentrations in KO mice. Results: Inulin supplementation can effectively alleviate hyperuricemia, increase the expressions of ABCG2 in intestine, and downregulate expression and activity of hepatic XOD (xanthine oxidase) in KO mice. It was revealed that the levels of inflammatory cytokines and the LPS (lipopolysaccharide) were remarkably higher in the KO group than those in the WT group, indicating systemic inflammation of hyperuricemic mice, but inulin treatment ameliorated inflammation in KO mice. Besides, inulin treatment repaired the intestinal epithelial barrier as evidenced by increased levels of intestinal TJ (tight junction) proteins [ZO-1 (zonula occludens-1) and occluding] in KO mice. Moreover, serum levels of uremic toxins, including IS (indoxyl sulfate) and PCS (p -cresol sulfate), were reduced in inulin-treated KO mice. Further investigation unveiled that inulin supplementation enhanced microbial diversity and raised the relative abundance of beneficial bacteria, involving SCFAs-producing bacteria (e.g., Akkermansia and Ruminococcus). Additionally, inulin treatment increased the production of gut microbiota-derived SCFAs (acetate, propionate and butyrate concentrations) in KO mice, which was positively correlated with the effectiveness of hyperuricemia relief. Conclusions: Our findings showed that inulin may be a promising therapeutic candidate for the treatment of hyperuricemia. Moreover, alleviation of hyperuricemia by inulin supplementation was, at least, partially conciliated by modulation of gut microbiota and its metabolites. [ABSTRACT FROM AUTHOR]

Based on the analysis of complex terrains and current forest transportation equipment, a forest tracked vehicle prototype LY1352JP was developed. The road model and the virtual prototype of the chassis were constructed using dynamic simulation software RecurDyn. The optimal tension of the vehicle as well as its capabilities for crossing trenches, climbing vertical walls, uphill and downhill slopes were simulated. The simulation results showed that the optimum tension force of the chassis of the vehicle was 63 kN (kilonewton), accounting for 45% of the total vehicle weight. The maximum trench crossing width and vertical obstacle climbing height were 1.35 m and 0.45 m, respectively. The maximum uphill and downhill angles were 50° and 45°, respectively. Tests on the prototype capacity for crossing trenches, and uphill and downhill driving were carried out. The test results were in agreement with the simulation results. A cross-country performance of a fire truck based on the tracked vehicle chassis was conducted in an old-growth forest. Tests verified that the vehicle has a strong forest trafficability performance and can meet the needs for forest transportation. [ABSTRACT FROM AUTHOR]

Purpose: HIF-PHI (hypoxia-inducible factor prolyl hydroxylase inhibitor) was developed to improve renal anemia. This study was to evaluate the efficiency and safety of HIF-PHI in patients with non-dialysis-dependent chronic kidney disease (NDD-CKD). Methods: The literature was extracted from PubMed, EMBASE, the Cochrane Central Register of Controlled Trials, and the Wanfang database. Statistical tests and forest plots were depicted by Review Manager Version 5.3. The primary outcome was a change in hemoglobin level from baseline (ΔHb). Secondary outcomes were changes in ferritin (ΔFerritin), hepcidin (ΔHepcidin), and transferrin saturation from baseline (ΔTSAT), and adverse events (AEs). This study is registered with PROSPERO (registration number CRD42020199656). Results: Ten trials were included. The results showed that HIF-PHI improved the ΔHb [SMD 3.03 (95% CI 2.10, 3.96), P < 0.00001] in NDD patients. HIF-PHI reduced hepcidin levels in the NDD patients [SMD − 1.44 (95% CI − 2.19–0.70), P = 0.0002]. ΔFerritin values were reduced significantly in the HIF-PHI group [SMD − 1.08 (95% CI − 1.63–0.53), P = 0.0001]. However, ΔTSAT values showed no significant difference in the HIF-PHI group compared to the placebo group [SMD − 0.23 (95% CI − 0.66–0.21), P = 0.31]. In the safety assessment, HIF-PHI did not increase adverse events significantly [RR 0.98 (95% CI 0.88–1.10), P = 0.74]. Conclusion: HIF-PHI improves renal anemia and iron utilization disorder in NDD-CKD patients, without significantly more adverse events. [ABSTRACT FROM AUTHOR]

Environmental DNA (eDNA) metabarcoding has emerged as a potentially powerful tool to monitor invasive fish species. As an alternative (or complementary) tool for biodiversity monitoring, eDNA metabarcoding had been used to detect species in aquariums, which represents an important transit avenue for introducing non-indigenous species with high population densities. In this study, eDNA metabarcoding as well as morphological characterization were used to reveal the diversity of non-indigenous species in a large aquarium at Qingdao Underwater World. Environmental DNA metabarcoding of 14 water samples at five locations from the Big Water Tank detected 24 non-indigenous species and four putative non-indigenous operational taxonomic units (OTUs). In contrast, only 20 non-indigenous species were observed by morphological characterization. Some species undetected by morphological characterization, such as Oreochromis niloticus (Linnaeus, 1758), are highly adaptable to various environments and/or have invaded preferred regions where they threaten native aquatic species. eDNA metabarcoding also detected seven local fishes that were not identified by morphological characterization. However, analysis of OTU diversity among stations and sample replications revealed that eDNA varied within and/or between stations. Increasing sampling effort as well as negative controls are required to increase the detection rate of species and to eliminate false-positive OTUs. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the clinical value of computed tomography (CT) image-based texture analysis in predicting microvascular invasion of primary hepatocellular carcinoma (HCC). CT images of patients with HCC from May 2017 to May 2019 confirmed by surgery and histopathology were retrospectively analyzed. Image features including tumor margin, tumor capsule, peritumoral enhancement, hypoattenuating halo, intratumoral arteries, and tumor-liver differences were assessed. All patients were divided into microvascular invasion (MVI)–negative group (n = 34) and MVI-positive group (n = 68). Preoperative CT images were further imported into MaZda software, where the regions of interest of the lesions were manually delineated. Texture features of lesions based on pre-contrast, arterial, portal, and equilibrium phase CT images were extracted. Thirty optimal texture parameters were selected from each phase by Fisher's coefficient (Fisher), classification error probability combined with average correlation coefficient (POE+ACC), and mutual information (MI). Finally, receiver operating characteristic curve analysis was performed. The results showed that the Edmonson-Steiner grades, tumor size, tumor margin, and intratumoral artery characteristics were significantly different between the two groups (P = 0.012, < 0.001, < 0.001, = 0.003, respectively). There were 58 parameters with significant differences between the MVI-negative and MVI-positive groups (P < 0.001 for all). Among them, 12, 14, 17, and 15 parameters were derived from the pre-contrast phase, arterial phase, portal phase, and equilibrium phase respectively. According to the ROC analysis, optimal texture parameters based on the pre-contrast, arterial, portal, and equilibrium phases were 135dr_GLevNonU (AUC, 0.766; the cutoff value, 1055.00), Vertl_RLNonUni (AUC, 0.764; the cutoff value, 5974.38), 45dgr_GLevNonU (AUC, 0.762; the cutoff value, 924.34), and Vertl_RLNonUni (AUC, 0.754; the cutoff value, 4868.80), respectively. Texture analysis of preoperative CT images may be used as a non-invasive method to predict microvascular invasion in patients with primary hepatocellular carcinomas, and further to guide the treatment and evaluate prognosis. The most valuable parameters were derived from the gray-level run-length matrix. [ABSTRACT FROM AUTHOR]

Ectoine is widely produced by various bacteria as a natural cell protectant against environment stress, e.g., osmotic and temperature stress. Its protective properties therefore exhibit high commercial value, especially in agriculture, medicine, cosmetics, and biotechnology. Here, we successfully constructed an engineered Escherichia coli for the heterologous production of ectoine. Firstly, the ectABC genes from Halomonas elongata were introduced into E. coli MG1655 to produce ectoine without high osmolarity. Subsequently, lysA gene was deleted to weaken the competitive l-lysine biosynthesis pathway and ectoine bioconversion was further optimized, leading to an increase of ectoine titer by 16.85-fold. Finally, at the low cell density of 5 OD600/mL in Erlenmeyer flask, the concentration of extracellular ectoine was increased to 3.05 mg/mL. At the high cell density of 15 OD600/mL, 12.7 g/L of ectoine was achieved in 24 h and the overall yield is 1.27 g/g glycerol and sodium aspartate. Our study herein provides a feasible and valuable biosynthesis pathway of ectoine with a potential for large-scale industrial production using simple and cheap feedstocks. [ABSTRACT FROM AUTHOR]

Objective: To explore the correlation between body composition measurement by bioelectrical impedance analysis (BIA) and intradialytic hypotension (IDH). Methods: The clinical data of 127 patients with end-stage renal disease (ESRD) who underwent regular dialysis in the Blood Purification Center of the Second Affiliated Hospital of Chongqing Medical University were retrospectively analyzed. According to the occurrence of IDH, the patients were divided into IDH group and intradialytic normotension group. The difference in body composition measured by BIA and its relationship with IDH were compared between the two groups. Results: Compared with intradialytic normotension group, the intracellular water (ICW) ratio (P = 0.009), extracellular water (ECW) ratio (P = 0.029), total body water (TBW) ratio (P = 0.012), protein ratio (P = 0.010), soft lean mass (SLM) ratio (P = 0.011), fat-free mass (FFM) ratio (P = 0.012) and skeletal muscle mass (SMM) ratio (P = 0.009) in IDH group were significantly decreased. However, the fat mass (FM) ratio (P = 0.016), percentage body fat (PBF) ratio (P = 0.001), extracellular water/total body water (ECW/TBW) ratio (P = 0.036), extracellular water/total body water in trunk (ECW/TBWT) ratio (P = 0.045) and visceral fat area (VFA) (P = 0.003) in IDH group were significantly increased when compared with intradialytic normotension group. In addition, there was a positive correlation between systolic blood pressure (SBP) during IDH and ECW ratio, ECW/TBW ratio, and ECW/TBWTR ratio before dialysis. Conclusions: The body composition of dialysis patients is closely related to the occurrence of IDH. Strengthening the body composition management of dialysis patients outside the hospital may reduce the occurrence of IDH and improve the long-term prognosis of dialysis patients. [ABSTRACT FROM AUTHOR]

For the multi-sample equal covariance function (ECF) testing problem, Zhang (Analysis of variance for functional data, CRC Press, Boca Raton, 2013) proposed an L 2 -norm-based test. However, its asymptotic power and finite sample performance have not been studied. In this paper, its asymptotic power is investigated under some mild conditions. It is shown that the L 2 -norm-based test is root-n consistent. In addition, intensive simulation studies are conducted to evaluate its finite sample performance against several existing competitors. In particular, they demonstrate that in terms of size control and power, the L 2 -norm-based test outperforms the dimension-reduction-based tests proposed by Panaretos et al. (J Am Stat Assoc 105(490):670–682, 2010) and Fremdt et al. (Scand J Stat 40(1):138–152, 2013), respectively, when functional data are less correlated or when the covariance function differences of functional data contain mainly high-frequency signals. Two real data applications are presented to illustrate the L 2 -norm-based test. [ABSTRACT FROM AUTHOR]

Purpose: The demand for titanium dental implants has risen sharply. However, the clinical success rate of implant surgery needs to be improved. In this paper, we report a novel surface modification strategy, large-grit sandblasting combined with micro-arc oxidation (SL-MAO), aiming to promote peri-implant bone formation and osseointegration of titanium implants. Materials and methods: Modified titanium samples were prepared by large-grit sandblasting and acid etching (SLA), micro-arc oxidation (MAO), and SL-MAO. The resulting topographical changes and chemical composition of the samples were examined by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS), respectively, and the biocompatibility and bioactivity were analyzed by bone-marrow mesenchymal stem cells (BMMSC) adhesion tests. Modified titanium implants were also inserted into the femurs of beagle dogs, and their competence of osseointegration was appraised by quantitative histomorphometry and micro-computed-tomography (micro-CT) analyses. Results: Compared to SLA and MAO techniques, SL-MAO surface modification further enhanced titanium surfaces by creating a topographic morphology characterized by both micron-sized craters and sub-micron-scale pits, and resulted in superior chemical composition, which promoted cell adhesion, proliferation, and osteogenic differentiation. SL-MAO-modified titanium implants osseointegrated more efficiently than SLA or MAO controls, with significantly higher bone-area (BA) ratio and bone-implant contact (BIC) in the peri-implant region. Conclusions: The SL-MAO surface modification technique optimized the surface properties of titanium implants and enhanced peri-implant bone formation and osseointegration. [ABSTRACT FROM AUTHOR]

The natural products discovery program in our group utilizes deep-sea sediment-derived microorganisms and employs a bio-active guided isolation procedure and one strain many compounds (OSMAC) approach to screen bio-active natural products for practical applications in the medicinal and agricultural industry. OSMAC strategy is employed to stimulate secondary metabolite production through changing culture conditions. In this paper, we applied cultivation-dependent procedure, changing media type, leading to the discovery of a bio-active compound named inthomycin B (1) from a marine-derived Streptomyces sp. YB104. The compound was characterized based on extensive spectroscopic analyses and comparison to that in the reported literature. The quantification of inthomycin B demonstrated that Streptomyces sp. YB104 produced moderate yield of inthomycin B with a yield around 25 mg/l after 14 days. Thus, Streptomyces sp. YB104 was considered to be a useful potential as a first industrial-producing strain of inthomycins. [ABSTRACT FROM AUTHOR]

Mobile crowd-sensing applications produce useful knowledge of the surrounding environment, which makes our life more predictable. However, these applications often require users to contribute, consciously or unconsciously, location-related data for analysis, which gravely encroaches users' location privacy. Aggregate processing is a feasible way for preserving user privacy to some extent, and based on the mode, some privacy-preserving schemes have been proposed. However, existing schemes still cannot guarantee users' location privacy in the scenarios with low density participants. Meanwhile, user accountability also needs to be considered comprehensively to protect the system against malicious users. In this paper, we propose data aggregate statistics schemes with participant density-independent location privacy-protection for mobile crowd-sensing applications. First, we make use of multi-pseudonym mechanism to overcome the vulnerability due to low participant density. Then, to further handle sybil attacks, we propose two schemes based on the Paillier cryptosystem. In the basic scheme, we leverage non-interactive zero-knowledge proof technology to verify users' sensing data. In the advanced scheme, we present a novel verification framework, which also addresses the problem of user accountability, but at the cost of introducing a new entity. Finally, the theoretical analysis indicates that our scheme achieves the desired properties, and the performance experiments demonstrate that our scheme can achieve a balance among accuracy, privacy-protection and computational overhead. [ABSTRACT FROM AUTHOR]

Rhamnolipids have recently emerged as promising bioactive molecules due to their novel structures, diverse and versatile biological functions, lower toxicity, higher biodegradability, as well as production from renewable resources. The advantages of rhamnolipids make them attractive targets for research in a wide variety of applications. Especially rhamnolipids are likely to possess potential applications of the future in areas such as biomedicine, therapeutics, and agriculture. The purpose of this mini review is to provide a comprehensive prospective of biosurfactant rhamnolipids as potential antimicrobials, immune modulators, and virulence factors, and anticancer agents in the field of biomedicine and agriculture that may meet the ever-increasing future pharmacological treatment and food safety needs in human health. [ABSTRACT FROM AUTHOR]

Changium smyrnioides is an endemic medicinal plant in China with considerable capacity for the production of furanocoumarins which can be used in many pharmaceutical applications. Although C. smyrnioides culture systems are regarded as potential resource of furanocoumarins, there is a lack of systematic study on elicitation of these secondary metabolites. Hence a furanocoumarin-oriented cell culture system of C. smyrnioides was established and several promising elicitors and their combinations were tested. The 10th day of the growth curve was chosen as the time point for elicitation. Treatments involving plant signal molecules such as methyl jasmonate (MeJA), salicylic acid (SA) and CaCl triggered furanocoumarin accumulation and suppressed cell growth, while heavy metals (CuSO and AgNO) showed little effects. MeJA at 0.1 mM enhanced the maximum productions of xanthotoxin and bergapten (1.1-fold and 39.6-fold higher than control). 100 mM CaCl triggered the highest bergaptol production (77.1-fold higher than control). Combinations of elicitors stressed the growth much more heavily than single elicitors. CaCl showed synergistic actions with MeJA and SA. 0.1 mM MeJA combined with 100 mM CaCl induced the highest contents of 3 furanocoumarins (Bergaptol, xanthotoxin and bergapten contents were 106.3, 1.6 and 59.9 times higher than those in control). All effective elicitors or combinations aroused oxidative and osmotic stresses in cell cultures and then triggered stress defence. The present study provided a new way for the exploitation of C. smyrnioides. [ABSTRACT FROM AUTHOR]

China's public enforcement regime has long been blamed for insufficiently and ineffectively deterring securities crime. We collect data on public enforcement outcomes from documents disclosed by listed firms and find that law enforcement outputs have increased significantly since 2011, thanks to the efforts of the China Securities Regulatory Commission's 38 regional offices. However, due to the lack of a reliable private enforcement regime and the limitations of monetary penalties, the general enforcement of securities law is still regarded as weak. In addition, there exists a salient pattern of selective enforcement. Privately owned listed firms face a harsher regulatory environment in terms of both the number and severity of sanctions from regulators, whereas state-owned, and particularly central-government-controlled firms enjoy the most favourable treatment, although the gap has been reduced in recent years. [ABSTRACT FROM AUTHOR]

Mobile crowd-sensing can learn the aggregate statistics over personal data to produce useful knowledge about the world. Since personal data may be privacy-sensitive, the aggregator should only gain desired statistics without learning anything about the personal data. To guarantee differential privacy of personal data under an untrusted aggregator, existing approaches encrypt the noisy personal data, and allow the aggregator to get a noisy sum. However, these approaches lack of either efficient support of dynamic joins and leaves, or secure data-integrity verification, or fault tolerance. In this paper, we propose a novel private data aggregation scheme to address these issues for mobile crowd-sensing applications. In our scheme, we first design an efficient group management protocol to deal with the participants' dynamic joins and leaves. Then we enhance the scheme with data-integrity verification by considering the security vulnerability of limited data range. Moreover, we guarantee fault tolerance by leveraging a future message buffering mechanism, enabling continuously obtaining aggregate results and integrity verifications when failures happen. The analysis indicates that our scheme achieves desired properties, and the performance evaluation demonstrates the scheme's efficiency in terms of communication and computation overhead. [ABSTRACT FROM AUTHOR]

Natural products are an important source of modern medical development, e.g., antibiotics, anticancers, immune modulators, etc. and will continue to be a powerful driving force for the discovery of novel potential drugs. In the heterologous hosts, natural products are biosynthesized using dedicated metabolic networks. By gene engineering, pathway reconstructing, and enzyme engineering, metabolic networks can be modified to synthesize novel compounds containing enhanced structural feature or produce a large quantity of known valuable bioactive compounds. The review introduces some important technical platforms and relevant examples of genetic regulation and manipulation to improve natural product titers or drive novel secondary metabolite discoveries. [ABSTRACT FROM AUTHOR]

Ternary ferroelectric single crystal Pb(InNb)O-Pb(MgNb)O-PbTiO (PIN-PMN-PT) was grown by the modified Bridgman method. The compositional variation of different regions of the crystals was measured, and the segregation regularity of the crystals was proposed. Variations in the dielectric properties and domain structures of the PIN-PMN-PT single crystals were investigated as a function of temperature and composition, and the phase transformation behavior of the crystals was observed. The PIN-PMN-PT crystals showed high Curie temperatures ( T = 160-210 °C), ferroelectric phase transition temperatures ( T up to 132 °C) and coercive fields ( E = 6-8 kV/cm) as well as excellent piezoelectric properties ( d up to 2,800 pC/N) and electromechanical coefficients ( k > 0.90). As the temperature increased, k values remained relatively constant and d increased gradually prior to ferroelectric phase transformation, and these results reflect the wide temperature usage range of PIN-PMN-PT single crystals. The polarization ( P) and E of the crystals showed unique trends during the phase transformation process; high P and E values can be maintained prior to depolarization, which indicates that the PIN-PMN-PT single crystals are candidate materials for high-power applications. In summary, PIN-PMN-PT single crystals with ultrahigh electric properties, large coercive fields and excellent thermal stability may potentially be applied in harsh environments. [ABSTRACT FROM AUTHOR]

Uric acid is a promising hydrophobic nitrogen source for biostimulation of microbial activities in oil-impacted marine environments. This study investigated metabolic processes and microbial community changes in a series of microcosms using sediment from the Mediterranean and the Red Sea amended with ammonium and uric acid. Respiration, emulsification, ammonium and protein concentration measurements suggested a rapid production of ammonium from uric acid accompanied by the development of microbial communities containing hydrocarbonoclastic bacteria after 3 weeks of incubation. About 80 % of uric acid was converted to ammonium within the first few days of the experiment. Microbial population dynamics were investigated by Ribosomal Intergenic Spacer Analysis and Illumina sequencing as well as by culture-based techniques. Resulting data indicated that strains related to Halomonas spp. converted uric acid into ammonium, which stimulated growth of microbial consortia dominated by Alcanivorax spp. and Pseudomonas spp. Several strains of Halomonas spp. were isolated on uric acid as the sole carbon source showed location specificity. These results point towards a possible role of halomonads in the conversion of uric acid to ammonium utilized by hydrocarbonoclastic bacteria. [ABSTRACT FROM AUTHOR]

Micro-nano structured Cu-Co was in situ fabricated on the surface of a gold electrode via electrochemical reduction of CuCl and Co(NO). It is shown that the shape of the particles can be controlled by variation of deposition current, deposition time, pH value and the ratio of Cu(II) and Co(II) ions. If prepared under current of −200 μA in 0.1 M, pH 4.0 acetate buffer solution, the film possesses high catalytic activity towards the electrochemical oxidation of glucose at a largely increased oxidation current compared to a non-modified surface. The electrochemical activity of this sensor can be easily tuned. Glucose is a standard compound for evaluating the chemical oxygen demand (COD), and we have therefore studied the application of the sensor to the determination of this parameter. Under optimized conditions, the sensor has linear response to glucose in the 1.92-768 mg L concentration range, and the detection limit is 0.609 mg L (at an S/N ratio of 3). A large number of surface water samples was studied, and the results obtained by this method were found to be linearly correlated to those obtained by the dichromate method (r = 0.995; n = 33). [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Anatase TiO with exposed {001} facets has been deepgoingly studied for optimizing its photocatalytic activity. In this study, we synthesized N-doped TiO nanocrystals with exposed {001} facets by sol-gel method and solvothermal method, respectively. The physical and chemical properties of as-synthesized samples, such as morphology, crystal phase, surface elements composition, porous structure, specific surface area, and optical response, were characterized in detail. The photocatalytic performances of all samples were evaluated by photocatalytic decoloration of methylene blue under visible-light irradiation ( λ > 420 nm). The results showed that the as-prepared samples present high visible-light photocatalytic performances, which can be ascribed to the excellent crystallization, the enhancement of absorbance in the visible-light region, and the strong adsorption performance, and calcination treatment is helpful to further improve the visible-light photocatalytic performance of N-doped TiO nanocrystals with exposed {001} facets. [ABSTRACT FROM AUTHOR]

Anaerobic ammonium oxidation (anammox) is the microbial conversion of ammonium and nitrite to dinitrogen gas. The functional microbes of anammox reaction are anammox bacteria, which were discovered in a wastewater treatment system for nitrogen removal. Anammox bacteria are prevalent in anoxic ecosystems and play an important role in both biological nitrogen cycle and nitrogen pollution control. In this paper, we reviewed the investigation on ecological characteristics of anammox bacteria, and tried to figure out their complicated intraspecies and interspecies relationships. As for intraspecies relationship, we focused on the quorum sensing system, a cell density-dependent phenomenon. As for interspecies relationship, we focused on the synergism and competition of anammox bacteria with other microorganisms for substrate and space. Finally, we discussed the great influence of environmental factors (e.g., dissolved oxygen, organic matters) on the constitution, structure and function of anammox bacteria community. [ABSTRACT FROM AUTHOR]

A nonlinear wavelet neural network (WNN) model with natural orthogonal expansion (NOE) and combined weights is constructed to predict the annual frequency of tropical cyclones (TCF) occurring over the coastal regions of Southern China. Combined weights are obtained by calculating categorical weights, based on the particle swarm projection pursuit, and ranking weights, based on fuzzy mathematics, followed by optimization. The global monthly mean heights at 500 hPa and sea-surface temperature fields are used as two predictors. The linear and nonlinear information of the predictors with reduced dimensions is gathered through the NOE and combined weights, respectively, and treated as the input into the WNN model. This model is first trained with the 55-year (i.e., 1950-2004) TCF data and then used to predict annual TCFs for the subsequent 5 years (i.e., 2005-2009). Results show that the mean absolute and relative errors are 0.6175 and 9.34 %, respectively. The impacts of the combined weights, NOE and WNN as well as the traditional multi-regression approach on the TCF prediction are examined. Results show superior performance of the WNN-based model in the annual TCF prediction. [ABSTRACT FROM AUTHOR]

The effect of β → α cooling rate during quenching on a new Zr-Sn-Nb-Fe-Cr-Cu alloy is reported. The microstructure evolution is well characterized by electron channeling contrast (ECC) imaging and transmission electron microscopy (TEM) techniques. The results show that specimens cooled by water, liquid nitrogen, air and furnace from β-phase present martensitic, coarse basket-weave, parallel-plate and lenticular structure, respectively. Residual β phase is detected by performing electron diffraction and composition analysis in the furnace cooled specimen. Micro hardness values of specimens decrease while the width of α laths increase with the cooling rate decreasing. The preliminarily established quantitative relationship among the cooling rate, microstructure and mechanical properties will shed light on the microstructure control and property optimization. [ABSTRACT FROM AUTHOR]

This study investigated the conjoined cellular oxidative damage of human embryo kidney 293T (HEK293T) cells induced by cadmium chloride (CdCl) and nanometer titanium dioxide (nano-TiO). RT-PCR technique was used to detect the expressions of Heme oxygenase-1 ( HO-1) and 8-oxoguanine DNA glycosylase ( OGG1). The activities of superoxide dismutase (SOD) and catalase enzyme (CAT) and concentrations of reactive oxygen species (ROS) and maldondialdehyde (MDA) were measured by different approaches. The results showed that CdCl and nano-TiO at a low concentration of 0.75 total toxic unit (TU) exerted an additive effects on HO-1 gene expression, CAT activities and MDA concentrations. When the total TU was increased to 1 or 1.25 TU, the interaction was synergetic. Moreover, the mixture with high proportion of CdCl produced an additive effect on the OGG1 gene expression, and the interaction was changed to be synergetic when the concentration of CdCl was lower than or equal to that of nano-TiO. Synergetic effects of CdCl and nano-TiO on cellular oxidative damage of HEK293T cells were found as indicated by the changes in the SOD activities and ROS concentrations. It was concluded that CdCl and nano-TiO exerts synergistic effects on the cellular oxidative damage of HEK293T cells, and the sensitivity of these indicators of oxidative damage varies with the proportion of CdCl and nano-TiO in the mixture. [ABSTRACT FROM AUTHOR]

Current efforts in the proteolysis targeting chimera (PROTAC) field mostly focus on choosing an appropriate E3 ligase for the target protein, improving the binding affinities towards the target protein and the E3 ligase, and optimizing the PROTAC linker. However, due to the large molecular weights of PROTACs, their cellular uptake remains an issue. Through comparing how different warhead chemistry, reversible noncovalent (RNC), reversible covalent (RC), and irreversible covalent (IRC) binders, affects the degradation of Bruton's Tyrosine Kinase (BTK), we serendipitously discover that cyano-acrylamide-based reversible covalent chemistry can significantly enhance the intracellular accumulation and target engagement of PROTACs and develop RC-1 as a reversible covalent BTK PROTAC with a high target occupancy as its corresponding kinase inhibitor and effectiveness as a dual functional inhibitor and degrader, a different mechanism-of-action for PROTACs. Importantly, this reversible covalent strategy is generalizable to improve other PROTACs, opening a path to enhance PROTAC efficacy. PROTACs have emerged as promising therapeutic agents but their cellular uptake is often inefficient. Here, the authors show that reversible covalent warhead chemistry improves PROTAC intracellular accumulation and target engagement, and develop a dual inhibitor/degrader of Bruton's tyrosine kinase [ABSTRACT FROM AUTHOR]

Chinese sturgeon (Acipenser sinensis), a critically endangered Acipenseridae family member, is one of the largest anadromous, native fish in China. Numerous research programmes and protection agencies have focused on breeding and preserving this endangered species. However, available information is limited on the different stages of sex development, especially on the reproductive regulation of the hypothalamus-pituitary-gonad (HPG) axis of A. sinensis. To unravel the mechanism of gene interactions during sex differentiation and gonad development of A. sinensis, we performed transcriptome sequencing using HPG samples from male and female A. sinensis in two developmental stages. In this study, 271.19 Gb high-quality transcriptome data were obtained from 45 samples belonging to 15 individuals (six in stage I, six males and three females in stage II). These transcriptomic data will help us understand the reproductive regulation of the HPG axis in the development stages of A. sinensis and provide important reference data for genomic and genetic studies in A. sinensis and related species. Design Type(s) development or differentiation design • transcription profiling design • sequence assembly objective • sequence annotation objective Measurement Type(s) transcription profiling assay Technology Type(s) RNA sequencing Factor Type(s) sex • developmental stage Sample Characteristic(s) Acipenser sinensis • pituitary gland • Hypothalamus • Gonad Machine-accessible metadata file describing the reported data (ISA-Tab format) [ABSTRACT FROM AUTHOR]