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Persistence of Aeromonas hydrophila in aquatic environments is the principle cause of fish hemorrhagic septicemia. Protistan predation has been considered to be a strong driving force for the evolution of bacterial defense strategies. In this study, we investigated the adaptive traits of A. hydrophila NJ-35, a carp pathogenic strain, in response to Tetrahymena thermophila predation. After subculturing with Tetrahymena, over 70% of A. hydrophila colonies were small colony variants (SCVs). The SCVs displayed enhanced biofilm formation, adhesion, fitness, and resistance to bacteriophage infection and oxidative stress as compared to the non-Tetrahymena-exposed strains. In contrast, the SCVs exhibited decreased intracellular bacterial number in RAW264.7 macrophages and were highly attenuated for virulence in zebrafish. Considering the outer membrane proteins (OMPs) are directly involved in bacterial interaction with the external surroundings, we investigated the roles of OMPs in the antipredator fitness behaviors of A. hydrophila. A total of 38 differentially expressed proteins were identified in the SCVs by quantitative proteomics. Among them, three lipoproteins including SurA, Slp, and LpoB, and a serine/threonine protein kinase (Stpk) were evidenced to be associated with environmental adaptation of the SCVs. Also, the three lipoproteins were involved in attenuated virulence of SCVs through the proinflammatory immune response mediated by TLR2. This study provides an important contribution to the understanding of the defensive traits of A. hydrophila against protistan predators.

Multicast can improve network performance by eliminating unnecessary duplicated flows in the data center networks (DCNs). Thus it can significantly save network bandwidth. However, the network multicast blocking may cause the retransmission of a large number of data packets and seriously influence the traffic efficiency in data center networks, especially in the fat-tree DCNs with multirooted tree structure. In this paper, we build a multicast blocking model and apply it to solve the problem of network blocking in the fat-tree DCNs. Furthermore, we propose a novel multicast scheduling strategy. In the scheduling strategy, we select the uplink connecting to available core switch whose remaining bandwidth is close to and greater than the three times of bandwidth multicast requests so as to reduce the operation time of the proposed algorithm. Then the blocking probability of downlink in the next time-slot is calculated in multicast subnetwork by using Markov chains theory. With the obtained probability, we select the optimal downlink based on the available core switch. In addition, theoretical analysis shows that the multicast scheduling algorithm has close to zero network blocking probability as well as lower time complexity. Simulation results verify the effectiveness of our proposed multicast scheduling algorithm.

Derivation of human naïve cells in the ground state of pluripotency provides promising avenues for developmental biology studies and therapeutic manipulations. However, the molecular mechanisms involved in the establishment and maintenance of human naïve pluripotency remain poorly understood. Using the human inducible reprogramming system together with the 5iLAF naïve induction strategy, integrative analysis of transcriptional and epigenetic dynamics across the transition from human fibroblasts to naïve iPSCs revealed ordered waves of gene network activation sharing signatures with those found during embryonic development from late embryogenesis to pre-implantation stages. More importantly, Transcriptional analysis showed a significant transient reactivation of transcripts with 8-cell-stage-like characteristics in the late stage of reprogramming, suggesting transient activation of gene network with human zygotic genome activation (ZGA)-like signatures during the establishment of naïve pluripotency. Together, Dissecting the naïve reprogramming dynamics by integrative analysis improves the understanding of the molecular features involved in the generation of naïve pluripotency directly from somatic cells.

Acoustic levitation system, with the advantages of avoiding clamping force on samples, has been widely introduced into noncontact manipulation. Previous acoustic levitation systems were generally fixed and could not realize remote adjustment of manipulation stage. In this article, we develop an ultrasonic robotic system for small object manipulation which is capable of noncontact operation, remote control, and gesture-based intelligent control. The whole setup is composed of acoustic levitation platform, mobile operation platform, and Kinect sensing system which provides a humanized approach for human–machine interaction. The experimental results validate a sufficient suite of innovations for achieving remote control of this acoustic levitation system based on gesture recognition method. It will not only pave a new way for noncontact manipulation system but also greatly reduce the difficulty and cost of operation.

Multitemporal Phased Array type L-band Synthetic Aperture Radar (PALSAR) horizontally transmitted and horizontally received (HH) coherence data was decomposed into temporal-coherence, spatial-coherence, and thermal noise components. The multitemporal data spanned between February and May of 2008, and consisted of two pairs of interferometric SAR (InSAR) images formed by consecutive repeat passes. With the analysis of ancillary data, a snow increase process and a snow decrease process were determined. Then, the multiple temporal-coherence components were used to study the variation of thawing and freezing statuses of snow because the components can mostly reflect the temporal change of the snow that occurred between two data acquisitions. Compared with snow mapping results derived from optical images, the outcomes from the snow increase process and the snow decrease process reached an overall accuracy of 71.3% and 79.5%, respectively. Being capable of delineating not only the areas with or without snow cover but also status changes among no-snow, wet snow, and dry snow, we have developed a critical means to assess the water resource in alpine areas.

Decadal to centennial land use and land cover change has been consistently singled out as a key element and an important driver of global environmental change, playing an essential role in balancing energy use. Understanding long-term human-environment interactions requires historical reconstruction of past land use and land cover changes. Most of the existing historical reconstructions have insufficient spatial and thematic detail and do not consider various land change types. In this context, this paper explored the possibility of using a cellular automata-Markov model in 90 m × 90 m spatial resolution to reconstruct historical land use in the 1930s in Zhenlai County, China. Then the three-map comparison methodology was employed to assess the predictive accuracy of the transition modeling. The model could produce backward projections by analyzing land use changes in recent decades, assuming that the present land use pattern is dynamically dependent on the historical one. The reconstruction results indicated that in the 1930s most of the study area was occupied by grasslands, followed by wetlands and arable land, while other land categories occupied relatively small areas. Analysis of the three-map comparison illustrated that the major differences among the three maps have less to do with the simulation model and more to do with the inconsistencies among the land categories during the study period. Different information provided by topographic maps and remote sensing images must be recognized.

Sweet potato, Ipomoea batatas (L.) Lam., is an important food crop that is cultivated worldwide. However, no genome-wide assessment of the genetic diversity of sweet potato has been reported to date. In the present study, the population structure and genetic diversity of 197 sweet potato accessions most of which were from China were assessed using 62,363 SNPs. A model-based structure analysis divided the accessions into three groups: group 1, group 2 and group 3. The genetic relationships among the accessions were evaluated using a phylogenetic tree, which clustered all the accessions into three major groups. A principal component analysis (PCA) showed that the accessions were distributed according to their population structure. The mean genetic distance among accessions ranged from 0.290 for group 1 to 0.311 for group 3, and the mean polymorphic information content (PIC) ranged from 0.232 for group 1 to 0.251 for group 3. The mean minor allele frequency (MAF) ranged from 0.207 for group 1 to 0.222 for group 3. Analysis of molecular variance (AMOVA) showed that the maximum diversity was within accessions (89.569%). Using CoreHunter software, a core set of 39 accessions was obtained, which accounted for approximately 19.8% of the total collection. The core germplasm set of sweet potato developed will be a valuable resource for future sweet potato improvement strategies.

Immunosuppression is common even in the early stage of severe sepsis. Interleukin-10 (IL-10) secretion and lymphocyte exhaustion are the main features of sepsis-induced immunosuppression. However, the relationship between IL-10 and the lymphocyte is still unclear. We investigated if IL-10/lymphocyte ratio (IL10LCR) were associated with mortality in severe septic patients.Adult patients with severe sepsis admitted to ICU of the First Affiliated Hospital of Guangzhou Medical University were identified from October 2012 to August 2013. Within 24 hours of ICU admission, peripheral whole blood was collected for the measurement of IL-10 using commercial multiplex bead-based assay kits and determination of lymphocyte count from laboratory data. The primary outcome was 28-day mortality.A total of 63 severe sepsis patients were identified. There were 20 (32%) patients died within 28 days. IL10LCR in non-survival patients was significantly higher than survival patients (median (IQR) 36.78 (12.34-79.63) ng/ml2 versus 11.01(5.41-27.50) ng/ml2, P = 0.002). Correlation analysis showed that IL10LCR was significantly correlated with APACHE II score (Spearman's rho = 0.424, P

Electrochemical oxygen reduction and oxygen evolution are two key processes that limit the efficiency of important energy conversion devices such as metal−air battery and electrolysis. Perovskite oxides are receiving discernable attention as potential bifunctional oxygen electrocatalysts to replace precious metals because of their low cost, good activity, and versatility. In this review, we provide a brief summary on the fundamentals of perovskite oxygen electrocatalysts and a detailed discussion on emerging high-performance oxygen electrocatalysts based on perovskite, which include perovskite with a controlled composition, perovskite with high surface area, and perovskite composites. Challenges and outlooks in the further development of perovskite oxygen electrocatalysts are also presented.

MSC-derived exosomes display, among others, an efficient biocompatibility and a reduced intrinsic immunogenicity, representing a valuable vehicle for drug delivery in a tumor-therapeutic approach. Following treatment of several human mesenchymal stroma/stem-like cell (MSC) populations with sub-lethal concentrations of taxol for 24 h, exosomes were isolated and applied to different human cancer populations including A549 lung cancer, SK-OV-3 ovarian cancer, and MDA-hyb1 breast cancer cells. While MSC control exosomes revealed little if any growth inhibition on the tumor cells, exposure to taxol-loaded MSC-derived exosomes was associated with 80−90% cytotoxicity. A similar application of taxol-loaded exosomes from HuVEC displayed much fewer effects. Quantification by LC-MS/MS analysis demonstrated a 7.6-fold reduced taxol concentration in MSC exosomes when compared to equivalent cytotoxic in vitro effects achieved with taxol substances, indicating a specific and more efficient tumor-targeting property. Consequently, MSC-derived taxol exosomes were tested in vivo. Highly metastatic MDA-hyb1 breast tumors were induced in NODscid mice, and systemic intravenous application of MSC-derived taxol exosomes revealed a more than 60% reduction of subcutaneous primary tumors. Moreover, the amount of distant organ metastases observed at least in lung, liver, spleen, and kidney was reduced by 50% with MSC taxol exosomes, similar to the effects observed with taxol, although the concentration of taxol in exosomes was about 1000-fold reduced. Together, these findings in different cancer cell populations and in vivo provide promising future perspectives for drug-loaded MSC-derived exosomes in efficiently targeting primary tumors and metastases by reducing side effects.

Alkali-treated titanium (Ti) with a porous, homogeneous, and uniform nanonetwork structure (TNS) that enables establishment of a more rapid and firmer osteointegration than titanium has recently been reported. However, the mechanisms underlying the enhanced osteogenic activity on TNS remains to be elucidated. This study aimed to evaluate the surface physicochemical properties of Ti and TNS, and investigate osteoinduction and osteointegration in vivo. Surface characteristics were evaluated using scanning electron microscopy (SEM), scanning probe microscopy (SPM), and X-ray photoelectron spectrometry (XPS), and the surface electrostatic force of TNS was determined using solid zeta potential. This study also evaluated the adsorption of bovine serum albumin (BSA) and human plasma fibronectin (HFN) on Ti and TNS surfaces using quartz crystal microbalance (QCM) sensors, and apatite formation on Ti and TNS surfaces was examined using a simulated body fluid (SBF) test. Compared with Ti, the newly developed TNS enhanced BSA and HFN absorbance capacity and promoted apatite formation. Furthermore, TNS held less negative charge than Ti. Notably, sequential fluorescence labeling and microcomputed tomography assessment indicated that TNS screws implanted into rat femurs exhibited remarkably enhanced osteointegration compared with Ti screws. These results indicate that alkali-treated titanium implant with a nanonetwork structure has considerable potential for future clinical applications in dentistry and orthopedics.

In this paper, thermal cycles with different heat inputs and cooling rates were investigated for a novel lean duplex stainless steel 2002 using a welding simulation. The microstructure and pitting resistance of the simulated heat-affected zones were studied. With the increasing heat input, the amount and size of the austenite phase both increased, along with a transformation from rods to dendritic structures. The critical pitting temperature (CPT) and the pitting potential (Epit) both increased first and then declined as the heat input increased, indicating a strong dependence of pitting resistance on the heat input. For the different cooling rates, the amount of ferrite increased as the cooling rate increased from 0.25 °C/s to 20 °C/s. The CPT and Epit both increased with the increasing cooling rates, indicating an improved pitting resistance. The pits initiated preferentially at the boundaries of ferrite and austenite due to the precipitation of M23C6 in the specimens with different cooling rates.

For a mobile robot, navigation skills that are safe, efficient, and socially compliant in crowded, dynamic environments are essential. This is a particularly challenging problem as it requires the robot to accurately predict pedestrians’ movements, analyse developing traffic situations, and plan its own path or trajectory accordingly. Previous approaches still exhibit low accuracy for pedestrian trajectory prediction, and they are prone to generate infeasible trajectories under complex crowded conditions. In this paper, we develop an improved socially conscious model to learn and predict a pedestrian’s future trajectory. To generate more efficient and safer trajectories in a changing crowed space, an online path planning algorithm considering pedestrians’ predicted movements and the feasibility of the candidate trajectories is proposed. Then, multiple traffic states are defined to guide the robot finding the optimal navigation strategies under changing traffic situations in a crowded area. We have demonstrated the performance of our approach outperforms state-of-the-art approaches with public datasets, in low-density and simulated medium-density crowded scenarios.

Feline parvovirus (FPV) infection is highly fatal in felines. NS1, which is a key nonstructural protein of FPV, can inhibit host innate immunity and promote viral replication, which is the main reason for the severe pathogenicity of FPV. However, the mechanism by which the NS1 protein disrupts host immunity and regulates viral replication is still unclear. Here, we identified an FPV M1 strain that is regulated by the NS1 protein and has more pronounced suppression of innate immunity, resulting in robust replication. We found that the neutralization titer of the FPV M1 strain was significantly lower than that of the other strains. Moreover, FPV M1 had powerful replication ability, and the FPV M1-NS1 protein had heightened efficacy in repressing interferon-stimulated genes (ISGs) expression. Subsequently, we constructed an FPV reverse genetic system, which confirmed that the N588 residue of FPV M1-NS1 protein is a key amino acid that bolsters viral proliferation. Recombinant virus containing N588 also had stronger ability to inhibit ISGs, and lower ISGs levels promoted viral replication and reduced the neutralization titer of the positive control serum. Finally, we confirmed that the difference in viral replication was abolished in type I IFN receptor knockout cell lines. In conclusion, our results demonstrate that the N588 residue of the NS1 protein is a critical amino acid that promotes viral proliferation by increasing the inhibition of ISGs expression. These insights provide a reference for studying the relationship between parvovirus-mediated inhibition of host innate [ABSTRACT FROM AUTHOR]

Induced neural stem cells (iNSCs) can be directly transdifferentiated from somatic cells. One potential clinical application of the iNSCs is for nerve regeneration. However, it is unknown whether iNSCs function in disease models. We produced transdifferentiated iNSCs by conditional overexpressing Oct4, Sox2, Klf4, c-Mycin mouse embryonic fibroblasts. They expanded readily in vitro and expressed NSC mRNA profile and protein markers. These iNSCs differentiated into mature astrocytes, neurons and oligodendrocytes in vitro. Importantly, they reduced lesion size, promoted the recovery of motor and sensory function as well as metabolism status in middle cerebral artery stroke rats. These iNSCs secreted nerve growth factors, which was associated with observed protection of neurons from apoptosis. Furthermore, iNSCs migrated to and passed through the lesion in the cerebral cortex, where Tuj1+ neurons were detected. These findings have revealed the function of transdifferentiated iNSCs in vivo, and thus provide experimental evidence to support the development of personalized regenerative therapy for CNS diseases by using genetically engineered autologous somatic cells.

Recently, the simultaneous wireless information and power transfer (SWIPT) technique has been regarded as a promising approach to enhance performance of wireless sensor networks with limited energy supply. However, from a green communication perspective, energy efficiency optimization for SWIPT system design has not been investigated in Wireless Rechargeable Sensor Networks (WRSNs). In this paper, we consider the tradeoffs between energy efficiency and three factors including spectral efficiency, the transmit power and outage target rate for two different modes, i.e., power splitting (PS) and time switching modes (TS), at the receiver. Moreover, we formulate the energy efficiency maximization problem subject to the constraints of minimum Quality of Service (QoS), minimum harvested energy and maximum transmission power as non-convex optimization problem. In particular, we focus on optimizing power control and power allocation policy in PS and TS modes to maximize energy efficiency of data transmission. For PS and TS modes, we propose the corresponding algorithm to characterize a non-convex optimization problem that takes into account the circuit power consumption and the harvested energy. By exploiting nonlinear fractional programming and Lagrangian dual decomposition, we propose suboptimal iterative algorithms to obtain the solutions of non-convex optimization problems. Furthermore, we derive the outage probability and effective throughput from the scenarios that the transmitter does not or partially know the channel state information (CSI) of the receiver. Simulation results illustrate that the proposed optimal iterative algorithm can achieve optimal solutions within a small number of iterations and various tradeoffs between energy efficiency and spectral efficiency, transmit power and outage target rate, respectively.

This paper presents an induced voltage linear extraction method for disturbing force self-sensing in the application of giant magnetostrictive actuators (GMAs). In this method, a Kelvin bridge combined with an active device is constructed instead of a conventional Wheatstone bridge for extraction of the induced voltage, and an additional GMA is adopted as a reference actuator in the self-sensing circuit in order to balance the circuit bridge. The linear fitting of the measurement data is done according to the linear relationship between the disturbing forces and the integral of the induced voltage. The experimental results confirm the good performance of the proposed method, and the self-sensitivity of the disturbing forces is better than 2.0 (mV·s)/N.

Coronaviruses (CoVs) pose a major threat to human and animal health worldwide, which complete viral replication by hijacking host factors. Identifying host factors essential for the viral life cycle can deepen our understanding of the mechanisms of virus-host interactions. Based on our previous genome-wide CRISPR screen of a-CoV transmissible gastroenteritis virus (TGEV), we identified the host factor dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A), but not DYRK1B, as a critical factor in TGEV replication. Rescue assays and kinase inhibitor experiments revealed that the effect of DYRK1A on viral replication is independent of its kinase activity. Nuclear localization signal modification experiments showed that nuclear DYRK1A facilitated virus replication. Furthermore, DYRK1A knockout significantly downregulated the expression of the TGEV receptor aminopeptidase N (ANPEP) and inhibited viral entry. Notably, we also demonstrated that DYRK1A is essential for the early stage of TGEV replication. Transmission electron microscopy results indicated that DYRK1A contributes to the formation of double-membrane vesicles in a kinase-independent manner. Finally, we validated that DYRK1A is also a proviral factor for mouse hepatitis virus, porcine deltacoronavirus, and porcine sapelovirus. In conclusion, our work demonstrated that DYRK1A is an essential host factor for the replication of multiple viruses, providing new insights into the mechanism of virus-host interactions and facilitating the development of new broad-spectrum antiviral drugs. IMPORTANCE Coronaviruses, like other positive-sense RNA viruses, can remodel the host membrane to form double-membrane vesicles (DMVs) as their replication organelles. Currently, host factors involved in DMV formation are not well defined. In this study, we used transmissible gastroenteritis virus (TGEV) as a virus model to investigate the regulatory mechanism of dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A) on coronavirus. Results showed that DYRK1A significant ly inhibited TGEV replication in a kinase-independent manner. DYRK1A knockout (KO) can regulate the expression of receptor aminopeptidase N (ANPEP) and endocytic-related genes to inhibit virus entry. More importantly, our results revealed that DYRK1A KO notably inhibited the formation of DMV to regulate the virus replication. Further data proved that DYRK1A is also essential in the replication of mouse hepatitis virus, porcine deltacoronavirus, and porcine sapelovirus. Taken together, our findings demonstrated that DYRK1A is a conserved factor for positive-sense RNA viruses and provided new insights into its transcriptional regulation activity, revealing its potential as a candidate target for therapeutic design. [ABSTRACT FROM AUTHOR]

A critical issue in battery-powered sensor networks is to construct energy efficient virtual backbones for network routing. Recent study in battery technology reveals that batteries tend to discharge more power than needed and reimburse the over-discharged power if they are recovered. In this paper we first provide a mathematical battery model suitable for implementation in sensor networks. We then introduce the concept of battery-aware connected dominating set (BACDS) and show that in general the minimum BACDS (MBACDS) can achieve longer lifetime than the previous backbone structures. Then we show that finding a MBACDS is NP-hard and give a distributed approximation algorithm to construct the BACDS. The resulting BACDS constructed by our algorithm is at most (8+Δ)opt size, where Δ is the maximum node degree and opt is the size of an optimal BACDS. Simulation results show that the BACDS can save a significant amount of energy and achieve up to 30% longer network lifetime than previous schemes.

Anaerobic digestion of high-solid waste activated sludge (HS-WAS) with low organic content at different organic loading rates (OLR) by various pretreatments (thermal, alkaline and thermal-alkaline) was investigated in this study. Experimental results showed that no matter whether pretreatment methods were employed or not, the daily biogas production from HS-WAS with low organic content increased in the OLR range of 1.5-3.0 kg/m3·day. The biogas production and volatile solids (VS) reduction at different OLRs by different pretreatments had the same conclusion as follows: thermal-alkaline > thermal > alkaline > control. Further exploration revealed that the solubilization of organic matters in sludge was improved by various pretreatments, resulting in the enhancement of anaerobic digestion. Also, the accumulation of volatile fatty acids (VFAs) and ammonia nitrogen did not gave negative influences on the stability or the overall performance of HS-WAS anaerobic digestion. [ABSTRACT FROM AUTHOR]