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31.
Helicobacter pylori is a prevalent bacterium that can cause gastric ulcers and cancers. Lactic acid bacteria (LAB) ameliorate treatment outcomes against H. pylori, suggesting that they could be a source of bioactive molecules usable as alternatives to current antibiotics for which resistance is mounting. We developed an in vitro framework to compare the anti-H. pylori properties of 25 LAB and their secretions against H. pylori. All studies were done at acidic and neutralized pH, with or without urea to mimic various gastric compartments. Eighteen LAB strains secreted molecules that curtailed the growth of H. pylori and the activity was urea-resistant in five LAB. Several LAB supernatants also reduced the urease activity of H. pylori. Pre-treatment of H. pylori with acidic LAB supernatants abrogated its flagella-mediated motility and decreased its ability to elicit pro-inflammatory IL-8 cytokine from human gastric cells, without reverting the H. pylori-induced repression of other pro-inflammatory cytokines. This study identified the LAB that have the most anti-H. pylori effects, decreasing its viability, its production of virulence factors, its motility and/or its ability to elicit pro-inflammatory IL-8 from gastric cells. Once identified, these molecules can be used as alternatives or complements to current antibiotics to fight H. pylori infections.  相似文献   
32.
A continuously variable transmission (CVT) system transmits the engine/battery power to the car driving wheel smoothly and efficiently. Several types of CVT already been developed to improve the transmission losses while maintaining acceleration time. However, most of the CVT has some constraints in the actuation mechanism which led us to develop an innovative electromagnetic actuator for CVT. Simplified mathematical equations have been developed for the kinematics analysis of clamping forces of the CVT and electromagnetic forces of EMA. The EMA has been developed for ¼ scale car with two sets of solenoid. Each of the two sets has been equipped with primary and secondary pulleys for pushing and pulling the movable sheave. The solenoid is operated by controlling the supply current with a fuzzy logic controller. A simulation based fuzzy logic controller has been introduced here for identifying the desired current of the EMA actuation. The experimental results show that the EMA develops electromagnetic forces 301 N for the supply current of 3.37 amp, which makes the acceleration time of the car in the range of 2.5~3.5 sec and electromagnetic actuated CVT system highly energy efficient.  相似文献   
33.
Summarization is an important intermediate step for expediting knowledge discovery tasks such as anomaly detection. In the context of anomaly detection from data stream, the summary needs to represent both anomalous and normal data. But streaming data has distinct characteristics, such as one-pass constraint, for which conducting data mining operations are difficult. Existing stream summarization techniques are unable to create summary which represent both normal and anomalous instances. To address this problem, in this paper, a number of hybrid summarization techniques are designed and developed using the concept of reservoir for anomaly detection from network traffic. Experimental results on thirteen benchmark data streams show that the summaries produced from stream using pairwise distance (PSSR) and template matching (TMSSR) techniques can retain more anomalies than existing stream summarization techniques, and anomaly detection technique can identify the anomalies with high true positive and low false positive rate.  相似文献   
34.
Many manual labourers in Bangladesh are involved with metal-handling tasks that are both physically demanding and stressful. The metal workers have been significantly exposed to prolonged hammering and cutting activities in excessive noise and with awkward body postures. Moreover, stressors from heat and humidity, welding fumes and metal dusts often cause excess strain, and are reflected in a deterioration of their physical work performance. Indeed, physical work is the economic source in many developing countries for the support of worker's family and relatives. Unfortunately, there are many obstacles and a lack of efficient steps to restore ergonomics principles as well as occupational safety and health measures. Thus, in this paper, tasks, and jobs are classified and analysed from the results of an ergonomics survey from 343 subjects (293 adults men, age 20-40 years; 17 women, 19-32 years) and 33 child workers (14-17 years). Four types of metal working sites from two districts in Bangladesh were surveyed using questionnaires and interviews. The results showed that a significant number of workers experienced a high prevalence of work-related problems. The main aim was to identify stressful task that are related to musculoskeletal and psychosocial symptoms. Moreover, the findings reveal the possibility of why ergonomics measures are unsuccessful; and if they could have an immediate effect on the safety and health of metal workers in Bangladesh.  相似文献   
35.
Due to the extensive use of various intelligent terminals and the popularity of network social tools, a large amount of data in the field of medical emerged. How to manage these massive data safely and reliably has become an important challenge for the medical network community. This paper proposes a data management framework of medical network community based on Consortium Blockchain (CB) and Federated learning (FL), which realizes the data security sharing between medical institutions and research institutions. Under this framework, the data security sharing mechanism of medical network community based on smart contract and the data privacy protection mechanism based on FL and alliance chain are designed to ensure the security of data and the privacy of important data in medical network community, respectively. An intelligent contract system based on Keyed-Homomorphic Public Key (KH-PKE) Encryption scheme is designed, so that medical data can be saved in the CB in the form of ciphertext, and the automatic sharing of data is realized. Zero knowledge mechanism is used to ensure the correctness of shared data. Moreover, the zero-knowledge mechanism introduces the dynamic group signature mechanism of chosen ciphertext attack (CCA) anonymity, which makes the scheme more efficient in computing and communication cost. In the end of this paper, the performance of the scheme is analyzed from both asymptotic and practical aspects. Through experimental comparative analysis, the scheme proposed in this paper is more effective and feasible.  相似文献   
36.

Ultra high definition radio, low latency, high bandwidth, machine to machine communication and several emergence application like e-health, IOT etc. will be dominated by 5G in future networks. Therefore there is dire need of more capacity which in turn will demand more efficient spectrum sensing. In this paper we propose a new technique of FBMC spectrum sensing cognitive radio technique in future networks. The proposed technique provides programmability that allows dynamic and real time configuration of the operating channel. The simulation results have been verified in terms of various parameters and found satisfactory results.

  相似文献   
37.
Optimal utilization of resources in present-day communication networks is a challenging task. Routing plays an important role in achieving optimal resource utilization. The open shortest path first (OSPF) routing protocol is widely used for routing packets from a source node to a destination node. This protocol assigns weights (or costs) to the links of a network. These weights are used to determine the shortest path between all sources to all destination nodes. Assignment of these weights to the links is classified as an NP-hard problem. This paper formulates the OSPF weight setting problem as a multi-objective optimization problem, with maximum utilization, number of congested links, and number of unused links as the optimization objectives. Since the objectives are conflicting in nature, an efficient approach is needed to balance the trade-off between these objectives. Fuzzy logic has been shown to efficiently solve multi-objective optimization problems. A fuzzy cost function for the OSPF weight setting problem is developed in this paper based on the Unified And-OR (UAO) operator. Two iterative heuristics, namely, simulated annealing (SA) and simulated evolution (SimE) have been implemented to solve the multi-objective OSPF weight setting problem using a fuzzy cost function. Results are compared with that found using other cost functions proposed in the literature (Sqalli et al. in Network Operations and Management Symposium, NOMS, 2006). Results suggest that, overall, the fuzzy cost function performs better than existing cost functions, with respect to both SA and SimE. Furthermore, SimE shows superior performance compared to SA. In addition, a comparison of SimE with NSGA-II shows that, overall, SimE demonstrates slightly better performance in terms of quality of solutions.  相似文献   
38.
An investigation is reported in which two isolated strains, A. nigerand A. terreus, exhibited similar enzyme activity, but A. nigershowed the maximum pectinlyase activity (acidic). An enzyme extract of both the strains and commercial enzymes (Flaxzyme and Bioxylanase) softened jute cuttings within 24 hours. The physico-mechanical properties of jute cuttings after treatment with enzyme revealed that flaxzyme and A. terreusand a mixture of commercial enzymes had been found to be among the most effective in improving fibre separation, fineness, and stiffness.  相似文献   
39.
Pattern Analysis and Applications - The prime goal of creating synthetic digital data is to generate something very closer to real ones when the original data are scarce. However, the...  相似文献   
40.
Comments on the article by L. D. Smith et al (see record 2002-18352-001) regarding the role of graphs and tables in hard and soft psychology. In this comment, the authors argue that the value of graphs in psychology is not limited to hard science but can be extended to the softer domain of clinical practice, where it can serve as an effective communication tool. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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