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关键词： Cronobacter sakazakii   production environment   desiccation   RNA sequencing  

摘要： Cronobacter sakazakii is a typical example of a xerotolerant bacterium. It is epidemiologically linked to low-moisture foods like powdered infant formula (PIF) and is associated with high fatality rates among neonates. We characterized the xerotolerance in a clinically isolated strain, Cronobacter sakazakii ATCC (TM) 29544(T), and compared the desiccation tolerance with that of an environmental strain, C. sakazakii SP291, whose desiccation tolerance was previously characterized. We found that, although the clinical strain was desiccation-tolerant, the level of tolerance was compromised when compared with that of the environmental strain. Transcriptome sequencing (RNA-seq)-based deep transcriptomic characterization identified a unique transcriptional profile in the clinical strain compared with what was already known for the environmental strain. As RNA-seq was also carried out under different TSB growth conditions, genes that were expressed specifically under desiccated conditions were identified and denoted as desiccation responsive genes (DRGs). Interestingly, these DRGs included transcriptomic factors like fnr, ramA, and genes associated with inositol metabolism, a phenotype as yet unreported in C. sakazakii. Further, the clinical strain did not express the proP gene, which was previously reported to be very important for desiccation survival and persistence. Interestingly, analysis of the plasmid genes showed that the iron metabolism in desiccated C. sakazakii ATCC (TM) 29544(T) cells specifically involved the siderophore cronobactin, encoded by the iucABCD genes. Confirmatory studies using quantitative reverse transcription-PCR (qRT-PCR) determined that, though the secondary desiccation response genes were upregulated in C. sakazakii ATCC (TM) 29544(T), the level of upregulation was lower than that in C. sakazakii SP291. All these factors may collectively contribute to the compromised desiccation tolerance in the clinical strain. IMPORTANCE Cronobacter sakazaki

关键词： Circuit faults   Capacitors   Voltage measurement   Time-domain analysis   Legged locomotion   Capacitance   Reactive power   Capacitor bank connections   short circuit and open circuit faults   shunt capacitor bank   time-domain protection  

摘要： This paper presents protection and fault location of wye-connected shunt capacitor banks used in medium or high voltage applications. The proposed method is sensitive to single element failure obtained by using voltage adaptive instantaneous superimposed current in each phase. The change in equivalent reactance computed using time-domain signals is used to find the number of failed capacitor element and types of fault. The location of the faulted capacitor is identified using sign of the voltage difference of the lower and upper halves of the shunt capacitor bank. The performance of the proposed method is tested for various cases including identical faults, simultaneous faults, system voltage unbalance in both single and double wye-connected shunt capacitor banks. The method is also validated using field data collected from a 400 kV SCB for an internal fault. The proposed technique is compared with available methods and found accurate.

关键词： Photovoltaic (PV) systems   Differential power processing converter   Fault-tolerant control   Switch failure   Maximum power point tracking (MPPT)  

摘要： Considering the failure risk and cost-effectiveness of photovoltaic (PV) systems with high granularity maximum power point tracking (MPPT), a fault-tolerant strategy without redundant switches is proposed for the PV system based on differential power processing (DPP) converters. This fault-tolerant strategy optimizes the output power of the PV system under different converter fault conditions by adjusting the coordinated operation of the DPP converter and the centralized converter. Compared to previous methods, in the case of hardware cost advantage, the proposed fault-tolerant strategy achieves the stable operation of the PV system after the converter failure and completes the targeted power optimization of all PV modules. The PV system with the proposed fault-tolerant strategy operates in three modes: distributed MPPT (DMPPT) mode, the coexistence of DMPPT and centralized MPPT (CMPPT) mode, and CMPPT mode. The PV system operates in the DMPPT mode when no switch failure occurs in the DPP converter. In the latter two post-fault operating modes, this paper proposes a simple fault-tolerant method to remove the faulty DPP converter and adjust the MPPT coverage of the centralized converter to recover the power loss caused by the fault. The experimental results validate the proposed faulttolerant strategy.

关键词： Thermal runaway   Thermal risk   Assessment of the thermal risk   Copolymerization reaction   Free radical polymerization  

摘要： Thermal runaway primarily occurs during the course of copolymerization due to the release of large amounts of heat. In this paper, the thermal risk associated with styrene-methyl methacrylate bulk copolymerization was firstly investigated by differential scanning calorimetry (DSC) and accelerating rate calorimetry (ARC). The result found that the exothermic behavior was greatly affected by the initiator concentration, in contrast the exothermic enthalpy was not. This exothermic behavior was firstly illustrated via polymerization mechanism. The temperature and pressure have changed dramatically during the adiabatic runaway copolymerization, which demonstrated a great potential risk of thermal runaway. Kinetic parameters, such as TNR, TSADT was calculated accordingly, which provided guidance for the safety of storage and transportation. This study will provide a helpful safety assessment for the styrene-methyl methacrylate bulk copolymerization, which is widely used in industry.

关键词： endoplasmic reticulum   lipid droplets   peroxisomes   PEX3   protein targeting   membrane protein insertion   protein translocation   label-free quantitative mass spectrometry   differential protein abundance analysis   Zellweger syndrome  

摘要： Protein import into the endoplasmic reticulum (ER) is the first step in the biogenesis of around 10,000 different soluble and membrane proteins in humans. It involves the co- or post-translational targeting of precursor polypeptides to the ER, and their subsequent membrane insertion or translocation. So far, three pathways for the ER targeting of precursor polypeptides and four pathways for the ER targeting of mRNAs have been described. Typically, these pathways deliver their substrates to the Sec61 polypeptide-conducting channel in the ER membrane. Next, the precursor polypeptides are inserted into the ER membrane or translocated into the ER lumen, which may involve auxiliary translocation components, such as the TRAP and Sec62/Sec63 complexes, or auxiliary membrane protein insertases, such as EMC and the TMCO1 complex. Recently, the PEX19/PEX3-dependent pathway, which has a well-known function in targeting and inserting various peroxisomal membrane proteins into pre-existent peroxisomal membranes, was also found to act in the targeting and, putatively, insertion of monotopic hairpin proteins into the ER. These either remain in the ER as resident ER membrane proteins, or are pinched off from the ER as components of new lipid droplets. Therefore, the question arose as to whether this pathway may play a more general role in ER protein targeting, i.e., whether it represents a fourth pathway for the ER targeting of precursor polypeptides. Thus, we addressed the client spectrum of the PEX19/PEX3-dependent pathway in both PEX3-depleted HeLa cells and PEX3-deficient Zellweger patient fibroblasts by an established approach which involved the label-free quantitative mass spectrometry of the total proteome of depleted or deficient cells, as well as differential protein abundance analysis. The negatively affected proteins included twelve peroxisomal proteins and two hairpin proteins of the ER, thus confirming two previously identified classes of putative PEX19/PEX3 clients in

关键词： Stochastic differential equations   Magnus-type methods   Magnus-type Euler method   Magnus-type Milstein method   Magnus-type Derivative-free method  

摘要： In this paper, a class of new Magnus-type methods is proposed for non-commutative Ito stochastic differential equations (SDEs) with semi-linear drift term and semi-linear diffusion terms, based on Magnus expansion for non-commutative linear SDEs. We construct a Magnus-type Euler method, a Magnus-type Milstein method and a Magnus-type Derivative-free method, and give the mean-square convergence analysis of these methods. Numerical tests are carried out to present the efficiency of the proposed methods compared with the corresponding underlying methods and the specific performance of the simulation Ito integral algorithms is investigated.

关键词： Climate-smart   Conservation   Energy conservation   Knowledge   Social-ecology  

摘要： Conservation agriculture (CA) is shimmering up as a potential solution to food security, biodiversity, mitigating climate change effects on agriculture and water scarcity challenges. Adoption of CA found to be related not only ecological factors, but also depends on the characteristics of the adopter, their level of perception and the decision-making process. This paper examines the interactions and inter-relationship among climate change perception, energy perception, and level of knowledge on CA as dependent variables with a set of operating agroeconomic, social-ecological, communication variables from new alluvial zone of West Bengal. Total of 65 farm households are surveyed using non-random snowballing sampling method. From the study it has found that farmers' perception on energy, climate change perception, and knowledge on CA are interwoven with each other. As the farmers of the study region are in initial stage of adoption they need access to proper CA-related information and Upgradation of functional education through training, workshops, or demonstrations. Here are the points of interventions for successful on-farm adoption of CA. While land fragmentation and fuel cost are came up as two important predictors.

关键词： Deep learning   Spinal fractures   Tomography   X-ray computed   Diagnosis   differential  

摘要： Objectives To evaluate the performance of deep learning using ResNet50 in differentiation of benign and malignant vertebral fracture on CT. Methods A dataset of 433 patients confirmed with 296 malignant and 137 benign fractures was retrospectively selected from our spinal CT image database. A senior radiologist performed visual reading to evaluate six imaging features, and three junior radiologists gave diagnostic prediction. A ROI was placed on the most abnormal vertebrae, and the smallest square bounding box was generated. The input channel into ResNet50 network was 3, including the slice with its two neighboring slices. The diagnostic performance was evaluated using 10-fold cross-validation. After obtaining the malignancy probability from all slices in a patient, the highest probability was assigned to that patient to give the final diagnosis, using the threshold of 0.5. Results Visual features such as soft tissue mass and bone destruction were highly suggestive of malignancy;the presence of a transverse fracture line was highly suggestive of a benign fracture. The reading by three radiologists with 5, 3, and 1 year of experience achieved an accuracy of 99%, 95.2%, and 92.8%, respectively. In ResNet50 analysis, the per-slice diagnostic sensitivity, specificity, and accuracy were 0.90, 0.79, and 85%. When the slices were combined to ve per-patient diagnosis, the sensitivity, specificity, and accuracy were 0.95, 0.80, and 88%. Conclusion Deep learning has become an important tool for the detection of fractures on CT. In this study, ResNet50 achieved good accuracy, which can be further improved with more cases and optimized methods for future clinical implementation.

关键词： Mathematical and Computational Engineering  

摘要： Present work explores the quantitative and qualitative performance investigation of nine recently developed optimization algorithm along with state-of-the-art differential evolution and its variants for the economic optimization of cooling tower. Quantitative performance of the competitive algorithms evaluated based on the best solution, mean solution, success rate, and standard deviation results. Qualitative performance comparison of competitive algorithms obtained through statistical analysis of the obtained results. Statistical analysis is carried out with two different scenarios to identify the qualitative performance of recently developed algorithms alone and in the presence of stat-of-art differential evolution and its variants. The effect of different constraint handling methods on the performance of the competitive algorithms is identify and presented. The behaviour of all competitive algorithms is verified for sensitiveness of constraints. Finally, the convergence behaviour of the competitive algorithm in obtaining the minimum total cost solutions is also obtainable and discussed.

关键词： Planarians   PAHs   Differential accumulation  

摘要： It has been observed that freshwater planarians can accumulate cadmium in their head portions, with neurotoxicity and head loss accompanying this phenomenon. Since planarians exhibit head loss and symptoms of neurotoxicity in response to PAHs, we investigated the differential accumulation of pyrene and B[a]P in the body and head portions of Girardia tigrina, a freshwater planarian. It is evidenced that planarian head fragments present higher amounts of pyrene- and B[a]P-equivalents than body fragments, indicating a differential distribution of these compounds within planarian tissues.