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Objective. To investigate hypoxia-induced Nestin regulates lung cancer viability and metabolism by targeting transcription factors Nrf2, STAT3, and SOX2. Methods. Eighty-four cases of nonsmall cell lung cancer (nonsmall cell lung cancer, NSCLC), which had been treated from June 2020 to February 2021, were randomly selected from our clinicopathology database. Immunohistochemical staining of collected tissue cells was performed to assess the expression patterns of Nestin, STAT3, Nrf2, and SOX2. Data were quantified and statistically analyzed using one-way and two-way ANOVA tests with P < 0.05. Results. Clinicopathological findings showed significant differences in lymph node metastasis, tissue differentiation, and histology on induction of Nestin expression; Nestin expression correlated with STAT3, Nrf2, and SOX2 expression.Nestin/STAT3/SOX2/Nrf2 are involved in angiogenesis and lung cancer development. Conclusion. Hypoxia-induced Nestin promotes the progression of nonsmall lung cancer cells by targeting the downstream transcription factors STAT3, Nrf2, and SOX2. [ABSTRACT FROM AUTHOR]

The magnetic anomalies generated by the ferromagnetic targets are usually buried within uncontrollable interference sources, such as the power frequency and random noises. In particular, the variability of the geomagnetic field and the low signal-to-noise ratio (SNR) of the magnetic anomalies cannot be avoided. In this paper, to improve the performance of magnetic anomaly detection (MAD) with a low SNR, we propose a novel structured low-rank (SLR) decomposition-based MAD method. In addition, a new framework based on the SLR and singular value decomposition (SVD) is constructed, dubbed SLR-SVD, and the corresponding working principle and implemented strategy are elaborated. Through comparing the SLR-SVD with two state-of-the-art methods, including principal component analysis and SVD, the results demonstrate that the proposed SLR-SVD can not only suppress the noise sufficiently, i.e., improving 55.26% approximately of the SNR, but also retain more boundary information of magnetic anomalies, i.e., decreasing approximately 68.05% of the mean squared error and improving approximately 28.47% of the structural similarity index. [ABSTRACT FROM AUTHOR]

SUMMARY: Root growth relies on both cell division and cell elongation, which occur in the meristem and elongation zones, respectively. SCARECROW (SCR) and SHORT‐ROOT (SHR) are GRAS family genes essential for root growth and radial patterning in the Arabidopsis root. Previous studies showed that SCR and SHR promote root growth by suppressing cytokinin response in the meristem, but there is evidence that SCR expressed beyond the meristem is also required for root growth. Here we report a previously unknown role for SCR in promoting cell elongation. Consistent with this, we found that the scr mutant accumulated a higher level of reactive oxygen species (ROS) in the elongation zone, which is probably due to decreased expression of peroxidase gene 3, which consumes hydrogen peroxide in a reaction leading to Casparian strip formation. When the oxidative stress response was blocked in the scr mutant by mutation in ABSCISIC ACID 2 (ABA2) or when the redox status was ameliorated by the upbeat 1 (upb1) mutant, the root became significantly longer, with longer cells and a larger and more mitotically active meristem. Remarkably, however, the stem cell and radial patterning defects in the double mutants still persisted. Since ROS and peroxidases are essential for endodermal differentiation, these results suggest that SCR plays a role in coordinating cell elongation, endodermal differentiation, redox homeostasis and oxidative stress response in the root. We also provide evidence that this role of SCR is independent of SHR, even though they function similarly in other aspects of root growth and development. [ABSTRACT FROM AUTHOR]

This review summarizes the evaluation, design, and modification strategies of self-supported electrocatalysts, as well as the alternative reactions to replace oxygen evolution reaction at anode for electrocatalytic water splitting with lower energy consumption. [Display omitted] • Transition metal (TM) based self-supported electrocatalysts own potential as anode for hydrogen production at large current density. • The preparation methods of TM-based self-supported electrocatalysts are reviewed and compared. • The strategies to improve the intrinsic activity of catalysts for oxygen evolution reaction (OER) at anode are reviewed. • The challenges and outlooks of TM-based self-supported electrocatalysts as anode for water splitting are described. Hydrogen produced from water electrolysis is a promising alternative to fossil fuels. The oxygen evolution reaction (OER), which occurs at the anode, involves a four-electron transfer process and requires a large potential to overcome the energy barrier. To address this challenge and reduce the cost associated with noble-metal catalysts, transition metal (TM) based catalysts offer a cost-effective solution. Compared to powder catalysts, TM-based catalysts in situ grown on conductive substrates are more suitable for industrial hydrogen production at large current density. Additionally, oxidation reactions with lower thermodynamic potential than OER have been explored as alternatives to reduce power consumption in electrohydrolysis hydrogen production. In this review, we provide an overview of the evaluation criterion, selection of substrate, preparation methods for self-supporting catalysts and their respective advantages and disadvantages. We also discuss the principle of active site selection and various strategies for enhancing the activity of catalysts, including metal doping, heteroatom doping, co-doping of both, heterojunctions, amorphization, compositing with conductive materials, morphology engineering, and creating superhydrophilic and superaerophobic surface. We then examine alternative anode reactions, such as urea oxidation, hydrazine oxidation, glucose oxidation and alcohol oxidation reactions. Finally, we outline the current challenges in the design of electrocatalysts and anodic oxidation reactions and provide an outlook on the future of hydrogen production using TM-based self-supported electrocatalysts. [ABSTRACT FROM AUTHOR]

The emerging mobile crowdsensing applications are able to facilitate people's life in various aspects. A key factor to ensure that these applications can provide high-quality service is the sufficient participation of normal smartphone users. Therefore, a lot of effort has been made to design incentive mechanisms to motivate users to participate. Most of these works assume that users are associated with homogeneous costs across the whole sensing area, based on which many utility optimization models are proposed. In this paper, we consider the scenario where smartphone users have heterogeneous costs across the sensing area, i.e., users in different regions have different cost distributions. In this scenario, traditional mechanisms may generate sensing holes and recruit insufficient users in some regions with higher costs, which may lead to unsatisfactory service. To accommodate this issue, we propose two optimization models, which aim at maximizing the user cardinality and the sensing utility function for each region of the whole sensing area, respectively. We then design effective incentive mechanisms, which possess the desirable properties, including computational efficiency, individual rationality, budget feasibility, truthfulness, and good competitiveness. By conducting extensive experiments on the real-world geographical dataset, we demonstrate the effectiveness of the proposed mechanisms in achieving the good quality of service. [ABSTRACT FROM AUTHOR]

Graphical abstract Ni 3 C nanoparticles were controlled synthesized for lithium storage due to its high intrinsic electrical conductivity and chemical stability. Highlights • Nickel carbide (Ni 3 C) nanoparticles were controlled synthesized by a facile oil phase approach. • The resultant Ni 3 C exhibits large specific surface area and excellent electrical conductivity. • Ni 3 C can be treated as highly efficient electrode for Li-ion batteries. Abstract Herein, nickel carbide (Ni 3 C) nanoparticles were controlled synthesized by decomposing nickel acetylacetonate in oleylamine and oleic acid solvent at a comparatively low temperature of 280 °C. The resultant Ni 3 C nanoparticles with an average size of 18 nm exhibited large specific surface area and excellent electrical conductivity. And the charge transport during the Li+ intercalation and deintercalation processes can be effectively facilitated by this kind of unique structure. Serving as an anode material in lithium-ion batteries, the Ni 3 C nanoparticles presented a high stable specific capacity of 390.1 mAh g−1 during 100 cycles at a current density of 0.1 A g−1 and excellent rate performance (e.g. 152.1 mAh g−1 at 5 A g−1). This phenomenon attributed to the advantages of the high intrinsic electrical conductivity and chemical stability of Ni 3 C. The effective nanostructure of transition metal carbides provides a promising approach to synthesis stable electrode materials for energy and environmental related applications. [ABSTRACT FROM AUTHOR]

Current OER electrocatalysts are hardly applicable for industrial use, which demands high current density (≥ 1000 mA cm-2) at low overpotential (≤ 300 mV) with long-term stability (≥ 100 h). Herein self-supported heterojunction catalyst, NiCo-OH@Ni x Fe y O 4 on Fe foam (FF), is in situ synthesized using two-step corrosion engineering. It only requires an overpotential 275 mV to drive the current density of 1000 mA cm-2 with good long-term stability. Theoretical calculations reveal that such good performance is attributable to electron transfer from NiCo-OH to Ni x Fe y O 4 which weakens the adsorption energy of reaction intermediate (OOH*) to promote the release of O 2 and lowers the free energy barriers for the reaction. Furthermore, a water splitting cell with NiCo-OH@Ni x Fe y O 4 /FF as anode and CoP@FeP/FF as cathode demonstrates its potential for industrial application. The study presents a general strategy for in situ synthesis of heterojunction catalysts on metal foams using controlled corrosion engineering for various catalytic applications. [Display omitted] • NiCo-OH@Ni x Fe y O 4 heterojunction in situ grown on Fe Foam by corrosion engineering. • NiCo-OH@Ni x Fe y O 4 /FF shows great OER activity (j 1000 =275 mV) with long-term stability. • Regulated d-band center of metal site optimizes binding energy of intermediates. • DFT confirms lower ∆G of rate-determined step due to charge transfer at interface. • NiCo-OH@Ni x Fe y O 4 /FF is an excellent anode for industrial water splitting. [ABSTRACT FROM AUTHOR]

Cichoric acid (CA), extracted from edible plants and vegetables, is a potential natural nutraceutical, with antioxidant and hypoglycaemic biological functions. The objective of this study was to explore the potential underlying molecular mechanisms involved in normalizing diabetes-related changes in hyperglycaemia via pancreas apoptosis and muscle injury induced by multiple low-dose STZ (MLD-STZ) injection in response to dietary supplementation with CA. To induce the MLD-STZ diabetic mice, the C57BL/6J mice were intraperitoneally injected with STZ (50 mg/kg body weight) for consecutive five days. CA (60 mg/kg/d) was supplemented in drinking water for 4 weeks. Compared with control, CA inhibited pancreas apoptosis and adjusted islet function in diabetic mice, leading to an increase in insulin generation and secretion. Moreover, CA regulated mitochondrial biogenesis, glycogen synthesis, and inhibited inflammation via activating antioxidant responses, which contributes to the improvement in athletic ability and diabetic myopathy. In general, CA is a natural food-derived compound with the potential application for regulating glucose homeostasis and improving diabetes and its complications. [ABSTRACT FROM AUTHOR]

Spatial crowdsourcing and crowdsensing are two emerging crowdsourcing paradigms, which enable a variety of location-based query and sensing tasks. In spatial crowdsourcing, mobile workers are required to travel physically to target locations in order to complete query tasks. Most existing work, hence, has focused on designing efficient query task assignment schemes to maximize the task completion rate under traveling constraints of workers for spatial crowdsourcing systems. In crowdsensing, on the other hand, sensor recordings of workers’ smartphones are of interest and have been collected to build various applications. Therefore, work concerning crowdsensing has strived to maximize the coverage area of sensor trajectories by selecting a set of workers. In this paper, we investigate the integration of these two paradigms. We notice a key link between these paradigms: While a worker is traveling to the target location of a query task, his trajectory may provide valuable coverage for a sensing task. Therefore, we propose a task management framework, named SpatialRecruiter, to efficiently match workers to the merged query and sensing tasks. We propose two coverage estimation functions to compute the coverage potential of a worker. Then, we design a greedy heuristic to select and assign workers. The experimental results on a real-world dataset demonstrate that the proposed strategies are efficient and effective in meeting the requirements of both paradigms. [ABSTRACT FROM AUTHOR]

Mobile crowdsensing systems aim to provide various novel applications by employing pervasive smartphones. A key factor to enable such systems is substantial participation of normal smartphone users, which requires effective incentive mechanisms. In this paper, we investigate incentive mechanisms for online scenarios, where users arrive and interact with a task requester in a random order, and they have preferences (e.g., photographing) or limits (e.g., travel distance) over the sensing tasks. In existing online mechanisms, the task requester has limited power in assigning tasks to the selected users, i.e., it has to pay for all of the tasks specified by the selected users, although some of these tasks are of little value. To accommodate this, we investigate a more flexible setting, where the requester can actively assign most valuable tasks to the selected users. We design two online incentive mechanisms motivated by a sampling-accepting process and weighted maximum matching. We prove that the designed mechanisms achieve computational efficiency, individual rationality, budget feasibility, truthfulness, consumer sovereignty, and constant competitiveness. By carrying out extensive experiments on two real-world geographical datasets, we demonstrate the practical applicability of the proposed mechanisms. [ABSTRACT FROM PUBLISHER]

Off-the-shelf smartphones have boosted large scale participatory sensing applications as they are equipped with various functional sensors, possess powerful computation and communication capabilities, and proliferate at a breathtaking pace. Yet the low participation level of smartphone users due to various resource consumptions, such as time and power, remains a hurdle that prevents the enjoyment brought by sensing applications. Recently, some researchers have done pioneer works in motivating users to contribute their resources by designing incentive mechanisms, which are able to provide certain rewards for participation. However, none of these works considered smartphone users’ nature of opportunistically occurring in the area of interest. Specifically, for a general smartphone sensing application, the platform would distribute tasks to each user on her arrival and has to make an immediate decision according to the user’s reply. To accommodate this general setting, we design three online incentive mechanisms, named TBA, TOIM and TOIM-AD, based on online reverse auction. TBA is designed to pursue platform utility maximization, while TOIM and TOIM-AD achieve the crucial property of truthfulness. All mechanisms possess the desired properties of computational efficiency, individual rationality, and profitability. Besides, they are highly competitive compared to the optimal offline solution. The extensive simulation results reveal the impact of the key parameters and show good approximation to the state-of-the-art offline mechanism. [ABSTRACT FROM AUTHOR]

Crowdsourcing-based mobile applications are becoming more and more prevalent in recent years, as smartphones equipped with various built-in sensors are proliferating rapidly. The large quantity of crowdsourced sensing data stimulates researchers to accomplish some tasks that used to be costly or impossible, yet the quality of the crowdsourced data, which is of great importance, has not received sufficient attention. In reality, the low-quality crowdsourced data are prone to containing outliers that may severely impair the crowdsourcing applications. Thus in this work, we conduct pioneer investigation considering crowdsourced data quality. Specifically, we focus on estimating user motion trajectory information, which plays an essential role in multiple crowdsourcing applications, such as indoor localization, context recognition, indoor navigation, etc. We resort to the family of robust statistics and design a robust trajectory estimation scheme, name TrMCD, which is capable of alleviating the negative influence of abnormal crowdsourced user trajectories, differentiating normal users from abnormal users, and overcoming the challenge brought by spatial unbalance of crowdsourced trajectories. Two real field experiments are conducted and the results show that TrMCD is robust and effective in estimating user motion trajectories and mapping fingerprints to physical locations. [ABSTRACT FROM AUTHOR]

Intestinal colonization by antibiotic-resistant Enterococcus faecium is the first step in a process that can lead to infections in hospitalized patients. By comparative genome analysis and subsequent polymerase chain reaction screening, we identified a locus that encodes a putative phosphotransferase system (PTS). The PTS locus was widespread in isolates from hospital outbreaks of infection (84.2%) and nonoutbreak clinical infections (66.0%) but absent from human commensal isolates. Deletion of pstD, which is predicted to encode the enzyme IID subunit of this PTS, significantly impaired the ability of E. faecium to colonize the murine intestinal tract during antibiotic treatment. This is the first description of a determinant that contributes to intestinal colonization in clinical E. faecium strains. [ABSTRACT FROM AUTHOR]

Enterococcus faecium is a commensal of the gastrointestinal tract of humans and animals. Since the 1990s, it has also emerged as a nosocomial pathogen. Little is known about carbon metabolism of E. faecium even though the ability to utilize different sugars could be an important factor in adapting to different ecological niches. In this study we identify an E. faecium gene cluster that is responsible for the metabolism of the α-galactoside sugar raffinose. Phenotypic testing of seven E. faecium isolates of which the genomes were previously sequenced showed that one isolate (strain E980) could grow on raffinose. Genome analysis identified a gene cluster containing two genes encoding α-galactosidases (termed agaA and agaB) that was uniquely present in E980. The agaA and agaB genes were significantly more frequently found in strains that are phylogenetically related to E980 and were more prevalent in surveillance isolates from hospital and community sources than in isolates from clinical infections. Disruption of the α-galactosidase gene agaB, but not of agaA, disabled growth on raffinose in strain E980. In all strains agaA and agaB are carried on megaplasmids that are between 150 and 300 kb in size. Filter-mating experiments showed that the megaplasmid of E980 can be transferred to a plasmidless recipient which then gains the ability to grow on raffinose. The observation that raffinose utilization by E. faecium is a trait carried by megaplasmids indicates that these megaplasmids can have important roles in shaping the competitive fitness of E. faecium in the environment, for example by expanding the metabolic repertoire of this organism. [ABSTRACT FROM AUTHOR]

• Proteome revealed molecular regulatory mechanisms under ultrasonic stress. • Ultrasonic filed influenced various metabolic pathways in E. coli O157:H7 cells. • RpoS protein, MS channels, SOS response protein RecA were up-regulated. • Free radicals might enter into cells via activated mechanosensitive channels. • All-or-nothing effect might due to destruction of crucial cell defensive systems. The antimicrobial effects of ultrasonic filed have been studied for years at the phenotypic level, but there is little research to reveal the molecular regulatory mechanisms underlying the phenotypes. In this study, isobaric tag for relative and absolute quantification (iTRAQ) proteome was applied to analyze the regulatory networks of Escherichia coli O157:H7 in response to ultrasonic stress in whole-genome scale. A total of 1856 differentially expressed proteins were identified, of which 1141 were significant up-regulated and 715 down-regulated compared with live control cells. The comprehensive proteome coverage analysis showed that ultrasonic filed influenced various metabolic pathways in Escherichia coli O157:H7 cells. The ultrasound-induced up-regulation of global stress response regulator RpoS, bacterial mechanosensitive channels and SOS response protein RecA were described from the molecular level for the first time. In addition, we proposed a possible action mechanism that the free radicals produced by acoustic cavitation might enter into cells via the activated mechanosensitive channels, leading to the elevated intracellular ROS level and subsequent cell death. Last but not the least, we illustrated the all-or-nothing phenomenon of power ultrasound might due to the destruction of crucial cell defensive systems, including heat shock proteins and oxidative response regulators. These new findings can let us understand the ultrasonic effects more deeply and will contribute to this area. [ABSTRACT FROM AUTHOR]

Sheet-to-cloud cavitation in a Venturi pipe is investigated experimentally and numerically in this work. The multiscale vapor structures are simulated by Eulerian–Lagrangian multiscale modeling. The volume of fluid method with adaptive mesh refinement is employed to capture the macroscale cavity features, utilizing the large eddy simulation approach. The results of mesh sensitivity study demonstrate that second-order refinement is capable of capturing phase details and cavitation shedding behaviors. A comparison with experimental results reveals the mechanisms of different types of cavitation shedding induced by reentrant jet and shock wave. Taking microscale bubbles into account using the Lagrangian approach and achieving Eulerian–Lagrangian coupling, the multiscale cavitation features, including the morphological evolution of large cavities and characteristics of microbubbles, are accurately reproduced. The evolution features of microbubbles during pressure wave or condensation shock propagation are well recognized by different changing rates. The results indicate that shedding mechanisms in Venturi pipe cavitation can be categorized into three types: reentrant jet, condensation shock, and pressure wave. In the three conditions investigated in this work, shedding cycles are found to be mainly induced by the reentrant jet (σ = 1.03), reentrant jet, condensation shock, and pressure wave (σ = 0.64), and condensation shock (σ = 0.39), respectively, with a decrease in the cavitation number. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is a common malignancy with high morbidity and mortality worldwide. To date, chemotherapy plays an important role in the treatment of CRC patients. Multidrug resistance (MDR) is one of the major hurdles in chemotherapy for CRC, and the underlying mechanisms need to be explored. Studies have demonstrated that Wnt/β-catenin signaling plays a critical role in oncogenesis and tumor development, and its function in inhibiting apoptosis could facilitate tumor chemoresistance. Recent investigations have also suggested the regulatory effects of the Wnt/β-catenin signaling pathway in response to chemotherapeutic agents in CRC. Here, we particularly focus on reviewing the evidences suggesting the mechanisms of Wnt/β-catenin signaling in the chemoresistance modulation of colorectal cancer. [ABSTRACT FROM AUTHOR]

The Wnt/β-catenin signaling pathway is one of the highly conserved signaling pathway widely reported to play essential roles in the development of various tumors and human cancers, thus serving as a potential target for anticancer therapy. However, the specific effects of the related proteins in the Wnt/β-catenin signaling pathway in nasopharyngeal carcinoma (NPC) still remain elusive. Thus, this study was performed to uncover the correlation between the Wnt/β-catenin signaling pathway-related proteins and the clinical characteristics and prognosis of NPC. NPC tissues were revealed to present high expression of β-catenin and v-myc myelocytomatosis viral oncogene homolog (c-MYC) but low expression of Dickkopf-3 (DKK-3). Immunohistochemical staining revealed that DKK-3 was positively linked to but β-catenin and c-MYC were negatively linked to differentiation, tumor-node-metastasis (TNM) stage and lymph node metastasis of patients with NPC. In addition, c-MYC was identified to be positively correlated to DKK-3 in NPC tissues. The positive expression of β-catenin and c-MYC had negative relations with and that of DKK-3 had positive relations with survival rate of patients with NPC, which was analyzed by Kaplan-Meier method. Moreover, it was shown that later TNM stage and positive expression of β-catenin were risk factors for NPC-related death. These findings provide evidence that the proteins related to the Wnt/β-catenin signaling pathway (DKK-3, β-catenin, and c-MYC) participate in the development of NPC and positive expression of DKK-3 and negative expression of β-catenin, and c-MYC can serve as essential prognostic biomarkers, shedding new light on the prognosis and treatment of NPC. [ABSTRACT FROM AUTHOR]

Ongoing investigations of targeted therapeutic agents and their increased clinical applications, together with research in genomics and proteomics, have explored a variety of novel approaches for treatment of lung cancer, and 'molecular subtypes' have been defined based on specific actionable genetic aberrations. Liquid biopsies, including circulating tumor DNA (ctDNA) testing, are of value for cancer diagnosis and comprehensive genomic profiling, such as the identification of cancer subtypes and major genetic alterations in cancer cells. The case of a 66-year-old male patient with newly-diagnosed driver mutation-negative advanced non-small cell lung cancer (NSCLC) who underwent conventional therapy is described in the present report. The patient underwent regular monitoring, including continuous ctDNA analysis, imaging and assessment of tumor marker levels such as carcinoembryonic antigen (CEA). The patient initially presented with deep vein thrombosis which affected both lower extremities and without any symptoms in the lung, with a positron emission tomography scan identifying irregular pulmonary nodules in the right lower lobe and enlarged right supraclavicular lymph nodes. Subsequent ultrasound-guided fine-needle aspiration with nodule biopsy indicated advanced unresectable disease at stage IIIB based on the Tumor-Node-Metastasis staging system by the American Joint Committee on Cancer. Next-generation sequencing of tumor tissue and peripheral blood confirmed driver mutation-negative genes, including epidermal growth factor receptor, rat sarcoma, ALK receptor tyrosine kinase, ROS1 proto-oncogene receptor tyrosine kinase and rearrangement during transfection (RET). After 5 years of chemoradiotherapy and surveillance of ctDNA and CEA levels, detectable kinesin family member 5B (KIF5B)-RET fusion in ctDNA and rising CEA levels prompted early scans, which identified disease progression. The patient subsequently received the oral RET inhibitor pralsetinib, with treatment being currently ongoing for ≥17 months without detectable KIF5B-RET ctDNA or elevated CEA levels, with an ongoing minor response and stable disease based on Response Evaluation Criteria in Solid Tumors v1.1 on imaging. The present case illustrates the potential role of on-therapy circulating tumor biomarker monitoring as a non-traumatic method to evaluate therapy response and detect early disease progression in patients with advanced NSCLC. Integration of circulating tumor biomarker testing into the management of patients with advanced NSCLC requires additional prospective studies to actively assess and elucidate optimal treatment strategies. [ABSTRACT FROM AUTHOR]

Enterococcus faecium is a gut commensal of humans and animals. In the intestinal tract, E. faecium will have access to a wide variety of carbohydrates, including maltodextrins and maltose, which are the sugars that result from the enzymatic digestion of starch by host-derived and microbial amylases. In this study, we identified the genetic determinants for maltodextrin utilization of E. faecium E1162. We generated a deletion mutant of the mdxABCD-pulA gene cluster that is homologous to maltodextrin uptake genes in other Gram-positive bacteria, and a deletion mutant of the mdxR gene, which is predicted to encode a LacI family regulator of mdxABCD-pulA. Both mutations impaired growth on maltodextrins but had no effect on the growth on maltose and glucose. Comparative transcriptome analysis showed that eight genes (including mdxABCD-pulA) were expressed at significantly lower levels in the isogenic ΔmdxR mutant strain compared to the parental strain when grown on maltose. Quantitative real-time RT-PCR confirmed the results of transcriptome analysis and showed that the transcription of a putative maltose utilization gene cluster is induced in a semi-defined medium supplemented with maltose but is not regulated by MdxR. Understanding the maltodextrin metabolism of E. faecium could yield novel insights into the underlying mechanisms that contribute to the gut commensal lifestyle of E. faecium. [ABSTRACT FROM AUTHOR]

Enterococci, a type of lactic acid bacteria, are widely distributed in various environments and are part of the normal flora in the intestinal tract of humans and animals. Although enterococci have gradually evolved pathogenic strains causing nosocomial infections in recent years, the non-pathogenic strains have still been widely used as probiotics and feed additives. Enterococcus can produce enterocin, which are bacteriocins considered as ribosomal peptides that kill or inhibit the growth of other microorganisms. This paper reviews the classification, synthesis, antibacterial mechanisms and applications of enterocins, and discusses the prospects for future research. [ABSTRACT FROM AUTHOR]

Genome-wide functional genetic studies of food-borne pathogens could provide a comprehensive understanding of the mechanisms underline their survival and pathogenesis in the harsh environments during food processing and infections. Traditional methods such as physical mutagenesis, chemical mutagenesis, and labeled DNA fragment insertion mutation techniques are time-consuming, labor-intensive and low precision. Although RNA-Seq and other omics methods enable high-throughput research on a genome-wide scale, the obtained results of gene transcription or expression cannot establish direct causal connection between the genetic determinants and particular functions. Transposon sequencing (Tn-seq) is an emerging microbial functional genomic technology based on transposon mutagenesis and high-throughput sequencing technologies, which is able to quantitatively track millions of independent mutants in a single experiment, and therefore efficiently map the "genotype-phenotype" relationship and the genetic interaction networks of a bacterium. This article summarizes the common types and hazards of food-borne pathogens, the development of Tn-seq technology, and its applications in studying the physiology, pathogenesis, and environmental survival of food-borne pathogens. • Food-borne pathogens are a common concern of food safety worldwide. • Transposon sequencing (Tn-seq) is an emerging microbial functional genomics technology. • Tn-seq can efficiently establish "genotype-phenotype" correspondence. • The development and applications of Tn-seq are reviewed. [ABSTRACT FROM AUTHOR]

Nowadays, Enterococcus faecium is one of the leading nosocomial pathogens worldwide. Strains causing clinical infections or hospital outbreaks are enriched in the enterococcal surface protein (Esp) encoding ICEEfm1 mobile genetic element. Previous studies showed that Esp is involved in biofilm formation, endocarditis and urinary tract infections. In this study, we characterized the role of the putative AraC type of regulator (locus tag EfmE1162_2351), which we renamed ebrB and which is, based on the currently available whole genome sequences, always located upstream of the esp gene, and studied its role in Esp surface exposure during growth. A markerless deletion mutant of ebrB resulted in reduced esp expression and complete abolishment of Esp surface exposure, while Esp cell-surface exposure was restored when this mutant was complemented with an intact copy of ebrB. This demonstrates a role for EbrB in esp expression. However, during growth, ebrB expression levels did not change over time, while an increase in esp expression at both RNA and protein level was observed during mid-log and late-log phase. These results indicate the existence of a secondary regulation system for esp, which might be an unknown quorum sensing system as the enhanced esp expression seems to be cell density dependent. Furthermore, we determined that esp is part of an operon of at least 3 genes putatively involved in biofilm formation. A semi-static biofilm model revealed reduced biofilm formation for the EbrB deficient mutant, while dynamics of biofilm formation using a flow cell system revealed delayed biofilm formation in the ebrB mutant. In a mouse intestinal colonization model the ebrB mutant was less able to colonize the gut compared to wild-type strain, especially in the small intestine. These data indicate that EbrB positively regulates the esp operon and is implicated in biofilm formation and intestinal colonization. [ABSTRACT FROM AUTHOR]

Co-culturing two or more species has recently been used in fermenting foods for product flavor or safety control. Ethyl carbamate (EC) is a potential carcinogenic compound presented in Chinese yellow rice wine which can be reduced by fermentation starters modification. In this work, the effect of Lactobacillus brevis (L. brevis) on EC in yellow rice wine fermentation with Saccharomyces cerevisiae (S. cerevisiae) was studied and an optimal mixed-culture fermentation method was constructed according to comparative analyses of EC concentration and fundamental quality. EC concentration could be further reduced by 68.4% at most through adding 108 cfu/L L. brevis during S. cerevisiae fermentation. L. brevis also had beneficial influence on hedonic quality of yellow rice wine. Meanwhile, the effect of gallic acid on EC formation in this mixed-culture fermentation system was elucidated. Unfortunately, the coexistence of gallic acid and L. brevis attenuated their inhibitory effect on EC formation. Image 1 • Lactobacillus brevis is added to regulate EC in Chinese yellow rice wine. • An optimal mixed-culture fermentation with Lactobacillus brevis is constructed. • EC level can be reduced by 68.4% at most by adding 108 cfu/L Lactobacillus brevis. • Lactobacillus brevis has beneficial influence on hedonic quality of yellow rice wine. • Coexistence of gallic acid and Lactobacillus brevis attenuates their inhibitory effect on EC. [ABSTRACT FROM AUTHOR]

To study the effect of fine particle size and volume concentration on the performance of solid-liquid two-phase centrifugal pump, the mixture multiphase flow model, RNG k-ε turbulence model, and SIMPLEC algorithm were used to simulate the two-phase flow of the centrifugal pump. The effects of particle size and volume concentration on internal pressure distribution, solid volume distribution, and external characteristics were analyzed. The results show that under the design discharge conditions, with the increase of particle size and volume concentration, the internal pressure of the flow field will decrease, and the volume fraction of solid phase in the impeller passage will also decrease as a whole. The solid particles gradually migrate from the suction surface to the pressure surface, and the particles in the volute channel are mainly concentrated in the flow channel near the outlet side of the volute. With the increase of particle size and volume concentration, the negative pressure value at the inlet of centrifugal pump increases, the total pressure difference at the inlet and outlet decreases, and the head and efficiency decrease accordingly. [ABSTRACT FROM AUTHOR]

The traditional aeromagnetic compensation model does not consider the negative effects of the gradient of the geomagnetic background field. Especially in emergency aeromagnetic surveys, this gradient effect is obvious and can reduce the performance of magnetic compensation. To solve this problem, we propose a method of reducing the gradient effect of the magnetic sensor for aeromagnetic compensation. A magnetic gradient model of the Earth's background field is established for the aeromagnetic compensation, and the gradient effect is then suppressed using altitude data. An experimental platform was built, and flight tests were conducted. Comparison results show that the adoption of the proposed method increased the improvement ratio (IR) of our compensator on two flights from 20.4 and 21.3 to 25.9 and 26.0, with the growth rates of the IR, respectively, reaching 27% and 22%. [ABSTRACT FROM AUTHOR]

The gear transmission system is widely used in high-speed centrifugal pump to improve the operating speed and hydraulic performances of the whole pump. Vibration characteristics and the stability of these high-speed rotor systems with gear transmission have great impacts on the stability of the whole fluid transmission system of the plant. Based on the lumped-mass method and the principle of displacement equilibrium of the rotor system, a coupled lateral-torsional dynamic model describing the gear-rotor-seal-bearing (GRSB) system of high-speed centrifugal pumps which has considered the nonlinear factors within the gear pair, nonlinear forces of bearings, and those of the seals is proposed. Then, the stability and nonlinear vibration responses of a model GRSB system under different gear transmission ratios (i) have been studied. The following conclusions are drawn from the results: (1) The components with frequencies like fp, f g , fm, and 2fm have great impacts on the vibration responses of the gear pair, especially the fm component; moreover, the amplitude of fm first increases and then decreases with the ratio increase and reaches the maximum value under the ratio of 3. (2) A jump motion state will occur when the ratio i is 1.25 and the stability of the system is obviously worse than the bifurcation state. Quite different from those under the other states, under this jump motion state, the 0.2 f g component and 0.5fp component will appear in the vibration responses of both gears and become the most contributed two factors to the responses of the driven gear. (3) In the design process, the transmission ratio of a high-speed centrifugal pump with a simplified GRSB system should be specially designed to avoid the jump-point state and the maximum-amplitude-of-fm state to ensure the stability of the system as well as reduce the mechanical impacts and noises. [ABSTRACT FROM AUTHOR]

• A novel and practical method to inhibit ethyl carbamate (EC) is proposed. • Bamboo leaves extract (BLE) is added to regulate EC in Chinese yellow rice wine. • BLE addition can inhibit EC in the multi-microbial fermented wine. • BLE prevents the transformation from urea/citrulline to EC. • BLE dramatically influences arginine transport in Saccharomyces cerevisiae. Bamboo leaves extract (BLE) contains various effective ingredients, including phenolic compounds. In this study, the effect of BLE on ethyl carbamate (EC) formation was investigated in Chinese yellow rice wine brewing with three different fermentation starters (Saccharomyces cerevisiae , Saccharomyces cerevisiae and Lactobacillus brevis , and Chinese yeast). As a result, BLE showed significant inhibition effect on EC in multi-microbial fermented rice wine, by preventing the reactions between urea/citrulline and ethanol. We found that BLE had influence on arginine transport (GAP1, CAN1, ALP1, and VBA2 gene) in Saccharomyces cerevisiae (S. cerevisiae) , which significantly up-regulated arginine uptake gene expression in vacuole (VBA2 gene) so that inhibited arginine metabolism. Besides, the presence of BLE could improve the overall quality of Chinese yellow rice wine. Consequently, it was worthwhile applying BLE to Chinese rice wine fermentation, especially the wine brewing with S. cerevisiae and Lactobacillus brevis starter. [ABSTRACT FROM AUTHOR]

With the advancement of smartphones, mobile crowdsourcing has become a new computing paradigm to efficiently support novel mobile applications. Achieving good service quality of these applications, however, necessitates the participation of large number of smartphones, which can be obtained via providing suitable incentives to smartphone users. Nonetheless, most existing incentive mechanisms assume a centralized platform for recruiting smartphones, which is prone to expose the privacy of both smartphones and task requesters. In this context, this article studies a distributed truthful incentive mechanism (DTIM) for mobile crowdsourcing, where multiple auction rounds can be conducted locally in each smartphone and task requester. Specifically, in each auction round, the participating smartphones act as the sellers and submit bids to compete for their intended crowdsourcing tasks. The task requesters, on the other hand, act as the buyers that decide on the sellers and corresponding payments, depending on their submitted bids. Finally, based on the offered payment, each smartphone selects a buyer for trading to optimize its utility. It is shown that the proposed incentive mechanism is strategy-proof, budget balanced, individually rational, and computationally efficient. Numerical results provided corroborate the beneficial properties of the scheme. [ABSTRACT FROM AUTHOR]

Abstract Near-infrared (NIR) dyes have shown increasing popularity for photothermal cancer therapy. Here, we report the synthesis and photophysical properties of selenadiazolobenzotriazole based organic small molecule NIR dyes SeNz and SeNzBr , both of which demonstrate strong intramolecular charge transfer and an excellent photothermal effect. Through self-assembly, hydrophilic nanoparticles (NPs) SeNz NPs and SeNzBr NPs were prepared by taking DSPE-PEG 2000 as the polymer matrix and exhibited excellent photothermal conversion efficiency of 57.4% and 42.5%, respectively. In addition, both NPs displayed excellent photothermal stability and photostability. Furthermore, both NPs show low dark cytotoxicity and high phototoxicity by taking HeLa cells as the model. All results suggest that selenadiazolobenzotriazole based NIR dyes SeNz and SeNzBr are promising for photothermal therapy. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are vital post-transcriptional regulators that participate in host-pathogen interactions by modulating the expression of cellular factors. Previous studies have demonstrated that feline panleukopenia virus (FPV) alters miRNA expression levels within host cells. However, the relationship between FPV replication and host miRNAs remains unclear. Here, we demonstrated that FPV infection significantly altered cellular miR-92a-1–5p expression in F81 cells by upregulating the expression of specificity protein 1 (SP1). Furthermore, we observed that miR-92a-1–5p enhanced interferon (IFN-α/β) expression by targeting the suppressors of cytokine signaling 5 (SOCS5) that negatively regulates NF-κB signaling and inhibits FPV replication in host cells. These findings revealed that miR-92a-1–5p plays a crucial role in host defense against FPV infection. • FPV significantly altered miR-92a-1–5p expression in F81 cells by upregulating the expression of SP1. • SP1 is a vital transcriptional factor for miR-92a-1–5p expression. • MiR-92a-1–5p activated the NF-κB signaling pathway to promote IFN-I expression and inhibit FPV replication. [ABSTRACT FROM AUTHOR]

Enterococcus faecium is a common cause of nosocomial infections, of which infective endocarditis is associated with substantial mortality. In this study, we used a microarray-based transposon mapping (M-TraM) approach to evaluate a rat endocarditis model and identified a gene, originally annotated as "fruA" and renamed "bepA," putatively encoding a carbohydrate phosphotransferase system (PTS) permease (biofilm and endocarditis-associated permease A [BepA]), as important in infective endocarditis. This gene is highly enriched in E. faecium clinical isolates and absent in commensal isolates that are not associated with infection. Confirmation of the phenotype was established in a competition experiment of wild-type and a markerless bepA mutant in a rat endocarditis model. In addition, deletion of bepA impaired biofilm formation in vitro in the presence of 100% human serum and metabolism of β-methyl-D-glucoside. β-glucoside metabolism has been linked to the metabolism of glycosaminoglycans that are exposed on injured heart valves, where bacteria attach and form vegetations. Therefore, we propose that the PTS permease BepA is directly implicated in E. faecium pathogenesis. [ABSTRACT FROM AUTHOR]

Listeria monocytogenes is an important food-borne pathogen that can cause fatal listeriosis. High hydrostatic pressure (HHP) in combination with antimicrobial agent is a potential antibacterial strategy for controlling L. monocytogenes in the food industry. The aim of this study was to investigate the antibacterial effect and the underlying mechanisms of HHP alone and HHP in combination with Mannosylerythritol Lipid-A (MEL-A), an antimicrobial biosurfatant, on L. monocytogenes. The results of antibacterial rate and morphological changes showed that a combined HHP (100, 200, 300 MPa) and MEL-A (16 μg/mL, 32 μg/mL) treatment had a synergistic bactericidal effect on L. monocytogenes. The synergistic treatment caused severe damage to the cell membrane structure of L. monocytogenes. To further explore the antibacterial mechanism of the synergistic treatment of HHP and MEL-A on L. monocytogenes , genome-wide transcriptome analysis was carried out and identified 1392 differentially expressed genes (DEGs). Enrichment analysis of the DEGs showed that HHP induced significant down-expression of membrane-related genes and up-regulation of ribosome-related pathways (50 S and 30 S ribosomal proteins). Interestingly, ribosome was also the most significantly enriched pathway in the synergistic treatment group. Moreover, compared to HHP treatment alone, synergistic treatment also affected pathways related to the PTS system. In addition, the good safety performance in vivo and in vitro indicates that MEL-A could be potentially used as a potential additive for controlling L. monocytogenes in the food industry. This study reveals the synergistic bactericidal effect and mechanisms of a combined HHP and MEL-A treatment against L. monocytogenes , which may provide potential strategies for prevention and control of food-borne pathogens. • High hydrostatic pressure (HHP) and mannosylerythritol lipids-A (MEL-A) exhibited synergistic bactericidal effect. • Severe damage in cell membrane structure were observed by SEM and TEM. • Ribosome related pathways were significantly enhanced in both HHP and MH treatment groups. • In vitro and in vivo safety assessment experiments revealed the safety of MEL-A. [ABSTRACT FROM AUTHOR]

• Plasma-enhanced NH 3 -SCR of NO x over Cu-Mn/SAPO-34 is achieved at low temperatures. • There is no NH 3 slip and by-product formation in this process. • A maximum NO x removal of 80 % and 100 % N 2 selectivity are achieved. • Intermediates formed from the plasma NO oxidation promote the SCR of NO x. • Enhanced E–R reactions on the catalyst surface contribute to the enhanced NO x removal. In this work, a dielectric barrier discharge (DBD) plasma-enhanced NH 3 -selective catalytic reduction (NH 3 -SCR) of NO x over a Cu-Mn/SAPO-34 catalyst at low temperatures (<200 °C) and oxygen-rich conditions (14 vol.%) has been investigated using a two-stage post-plasma-catalytic (PPC) configuration. The results show a maximum NO x removal of 80 % and a 100 % N 2 selectivity without NH 3 slip or the formation of by-products at a low specific energy input (SEI) of 32 J/L. Adding water vapor (5.7 vol.%) into the plasma NH 3 -SCR process does not negatively affect the removal of NO x , while the presence of C 3 H 6 enhances the removal of NO x. In situ diffuse reflectance infrared spectroscopy (DRIFTS) combined with optical emission spectroscopic diagnostics has been employed to elucidate the reaction mechanism in the plasma-catalytic removal of NO x. We find that the formation of NO 2 via NO oxidation in the first stage plasma gas-phase reaction enhances the Eley-Rideal (E–R) reaction on the surface of the Cu-Mn/SAPO-34 catalyst in the second stage catalytic NH 3 -SCR of NO x. The Cu-Mn/SAPO-34 catalyst shows stable performance in the plasma-enhanced NH 3 -SCR of NO x after 5 cycles of catalyst regeneration. This work has successfully demonstrated a promising low-temperature plasma-catalytic solution for the effective NH 3 -SCR of NO x. [ABSTRACT FROM AUTHOR]

[Display omitted] Methicillin-resistant Staphylococcus aureus (MRSA) is drug-resistant and biofilm-forming pathogenic bacteria with severe morbidity and mortality, and has been continuously detected in food products in recent years. Mannosylerythritol lipids (MELs) are novel biosurfactants and perform antibacterial property against gram-positive bacteria. Ultrasound has been applied into food sterilization as non-thermal techniques and has advantage of maintaining food nutrition and flavor over heat pasteurization. In this work, the synergistic treatment of ultrasound and MEL-A was used to combat planktonic cells and biofilm of MRSA. As a result, the combined treatment has exhibited remarkable antibacterial effect proved by enumeration of viable microbes. Furthermore, flow cytometry, scanning electron microscopy and transmission electron microscopy revealed ultrasound has enhanced the inhibitory effect of MEL-A through exacerbating cell membrane damage. On the other hand, the collaborating working modes to eradicate MRSA biofilm were disturbing cell adhesion to surface by MEL-A and destructing mature biofilm mechanically by ultrasound, reaching to over 90% of clearance rate. The findings of this study illustrated the synergistic antimicrobial mechanism of ultrasound and MEL-A treatments, and offered theoretical basis for their potential applications in food preservation. [ABSTRACT FROM AUTHOR]

Chemotherapy is one of the most common strategies for tumor treatment but often associated with post-therapy tumor recurrence. While chemotherapeutic drugs are known to induce tumor cell senescence, the roles and mechanisms of senescence in tumor recurrence remain unclear. In this study, we used doxorubicin to induce senescence in breast cancer cells, followed by culture of breast cancer cells with conditional media of senescent breast cancer cells (indirect co-culture) or directly with senescent breast cancer cells (direct co-culture). We showed that breast cancer cells underwent the epithelial–mesenchymal transition (EMT) to a greater extent and had stronger migration and invasion ability in the direct co-culture compared with that in the indirect co-culture model. Moreover, in the direct co-culture model, non-senescent breast cancer cells facilitated senescent breast cancer cells to escape and re-enter into the cell cycle. Meanwhile, senescent breast cancer cells regained tumor cell characteristics and underwent EMT after direct co-culture. We found that the Notch signaling was activated in both senescent and non-senescent breast cancer cells in the direct co-culture group. Notably, the EMT process of senescent and adjacent breast cancer cells was blocked upon inhibition of Notch signaling with N-[(3,5-difluorophenyl)acetyl]-l-alanyl-2-phenyl]glycine-1,1-dimethylethyl ester (DAPT) in the direct co-cultures. In addition, DAPT inhibited the lung metastasis of the co-cultured breast cancer cells in vivo. Collectively, data arising from this study suggest that both senescent and adjacent non-senescent breast cancer cells developed EMT through activating Notch signaling under conditions of intratumoral heterogeneity caused by chemotherapy, which infer the possibility that Notch inhibitors used in combination with chemotherapeutic agents may become an effective treatment strategy. [ABSTRACT FROM AUTHOR]

The SARS-CoV-2 virus is still spreading worldwide, and there is an urgent need to effectively prevent and control this pandemic. This study evaluated the potential efficacy of Egg Yolk Antibodies (IgY) as a neutralizing agent against the SARS-CoV-2. We investigated the neutralizing effect of anti-spike-S1 IgYs on the SARS-CoV-2 pseudovirus, as well as its inhibitory effect on the binding of the coronavirus spike protein mutants to human ACE2. Our results show that the anti-Spike-S1 IgYs showed significant neutralizing potency against SARS-CoV-2 pseudovirus, various spike protein mutants, and even SARS-CoV in vitro. It might be a feasible tool for the prevention and control of ongoing COVID-19. [ABSTRACT FROM AUTHOR]

Mannosylerythritol lipids-A (MEL-A) is a novel biosurfactant with excellent surface activity and potential biomedical applications. In this study, we explored the antibacterial activity and the underlying mechanisms of MEL-A against the important food-borne pathogen Listeria monocytogenes. The bacterial growth and survival assays revealed a remarkable antibacterial activity of MEL-A. Since MEL-A is a biosurfactant, we examined the cell membrane integrity and morphological changes of MEL-A-treated bacteria by biochemical assays and flow cytometry analysis and electron microscopes. The results showed obvious damaging effects of MEL-A on the cell membrane and morphology. To further explore the antibacterial mechanism of MEL-A, a transcriptome analysis was performed, which identified 528 differentially expressed genes (DEGs). Gene ontology (GO) analysis revealed that the gene categories of membrane, localization and transport were enriched among the DEGs, and the analysis of the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways demonstrated significant changes in the maltodextrin ABC transporter system and stress response system. Furthermore, the growth of L. monocytogenes could also be significantly inhibited by MEL-A in milk, a model of a real food system, suggesting that MEL-A could be potentially applied as an natural antimicrobial agent to control food-borne pathogens in the food industry. [ABSTRACT FROM AUTHOR]