数字矿井及其相关技术分析

结合数字地球和数字中国战略的提出 ,对未来的数字矿井进行了构想 ,给出了数字矿井的基本框架 ,全面、系统地论述了数字矿井的相关技术———矿井空间数据的获取与分析技术、网络数据库与分布式计算技术、数据仓库及数据挖掘技术、多种数据整合及虚拟现实技术 ,最后指出数字矿井的作用和意义     

Energy Efficient System-on-chip Design for Wireless Body Area Sensor Network

This article presents a novel energy-efficient on-chip design for wireless body area sensor networks focused towards pervasive healthcare applications. The network adopts a master–slave architecture, where the body-worn slave nodes periodically send sensor readings to a central master node. Unlike traditional peer-to-peer wireless sensor networks, the nodes in this wireless body area sensor networks are not deployed in an ad hoc fashion. The network is centrally managed and all communications are single-hop. A cluster algorithm is also presented so that all slave nodes are within the transmission range of the master nodes. It pretends that all slave nodes can share resources and information over the internet to reduce energy consumption. The design on system-on-chip platform has been simulated for some experiments and implemented. Compared to published and industrially used schemes, the power consumption of the proposed design is over 30 and 99% lower in the simulation and platform implementation, respectively.     

GB virus-C/hepatitis G virus infection in an area endemic for viral hepatitis, chronic liver disease, and liver cancer

BACKGROUND & AIMS: GB virus-C/hepatitis G virus (GBV-C/HGV) is a newly identified flavivirus, and little is known about its clinical significance. GBV-C/HGV was investigated in different populations, and its coinfection was investigated in patients with liver disease in Taiwan where hepatitis B and C are endemic. METHODS: Viral RNA was studied in 70 high-risk individuals, 20 patients with chronic non-B, non-C hepatitis, 13 with non-A-E fulminant hepatitis, 100 with asymptomatic hepatitis B surface antigen carriage, 120 with hepatitis B surface antigen-positive chronic liver disease and hepatocellular carcinoma, 100 patients with chronic hepatitis C, and 100 healthy adults. RESULTS: GBV-C/HGV infection was more frequent in high-risk groups (15%-30%) and hepatitis C virus carriers (10%) than in healthy adults (1%) and hepatitis B virus carriers (3.2%). Eighty-three percent of those infected had undergone blood transfusions previously. The prevalence in hepatitis B virus carriers increased with the severity of liver disease, being 1% in asymptomatic carriers and 10% in hepatocellular carcinoma. In chronic hepatitis C, clinical and virological data were comparable between those with and without coinfection. CONCLUSIONS: In Taiwan, GBV-C/HGV infection is common in high-risk groups, and its coinfection seems to not aggravate the course of chronic hepatitis B or C.     

A learning style classification mechanism for e-learning

With the growing demand in e-learning, numerous research works have been done to enhance teaching quality in e-learning environments. Among these studies, researchers have indicated that adaptive learning is a critical requirement for promoting the learning performance of students. Adaptive learning provides adaptive learning materials, learning strategies and/or courses according to a student’s learning style. Hence, the first step for achieving adaptive learning environments is to identify students’ learning styles. This paper proposes a learning style classification mechanism to classify and then identify students’ learning styles. The proposed mechanism improves k-nearest neighbor (k-NN) classification and combines it with genetic algorithms (GA). To demonstrate the viability of the proposed mechanism, the proposed mechanism is implemented on an open-learning management system. The learning behavioral features of 117 elementary school students are collected and then classified by the proposed mechanism. The experimental results indicate that the proposed classification mechanism can effectively classify and identify students’ learning styles.     

IEEE802．15．4的MAC协议实现

IEEE802.15.4协议是无线传感网中多采用的一种低速率、低功耗、低成本的无线通信协议.Imote2是Intel公司推出的高集成度的无线传感器平台.文中介绍了Imote2平台以及IEEE802.15.4协议,及网络驱动程序的体系结构,给出了实现IEEE802.15.4的MAC协议过程中的关键函数,还对MAC协议实现中的中断服务响应以及时钟等关键问题进行了描述.并分别对节点的工作性能及组网时节点的性能及损耗进行了测试,给出了系统的性能.结果显示,该种实现方法有效地保证了系统的性能并且可以达到无线传感网组网需求.     

Aggregate Profit-Based Caching Replacement Algorithms for Streaming Media Transcoding Proxy Systems

This work derives a generalized video object profit function from the extended weighted transcoding graph to calculate the individual cache profit of certain versions of a video object, and the aggregate profit from caching multiple versions of the same video object. This proposed function takes into account the popularity of certain versions of an object, the transcoding delay among versions, and the average duration of access of each version. Based on the profit function, cache-replacement algorithms are proposed to reduce the startup delay and network traffic by efficiently caching video objects with the most profits. Two kinds of simulations were conducted to evaluate the performance of the proposed algorithms. These simulations exploit partial viewing traces and complete viewing traces, separately. The results demonstrate that the proposed algorithms outperform the competing algorithms by 15%-39% in delay saving ratio and 5%-10% in byte-hit ratio     

Impact of Amyloid Pathology in Mild Cognitive Impairment Subjects: The Longitudinal Cognition and Surface Morphometry Data

The amyloid framework forms the central medical theory related to Alzheimer disease (AD), and the in vivo demonstration of amyloid positivity is essential for diagnosing AD. On the basis of a longitudinal cohort design, the study investigated clinical progressive patterns by obtaining cognitive and structural measurements from a group of patients with amnestic mild cognitive impairment (MCI); the measurements were classified by the positivity (Aβ+) or absence (Aβ−) of the amyloid biomarker. We enrolled 185 patients (64 controls, 121 patients with MCI). The patients with MCI were classified into two groups on the basis of their [¹⁸F]flubetaben or [¹⁸F]florbetapir amyloid positron-emission tomography scan (Aβ+ vs. Aβ−, 67 vs. 54 patients) results. Data from annual cognitive measurements and three-dimensional T1 magnetic resonance imaging scans were used for between-group comparisons. To obtain longitudinal cognitive test scores, generalized estimating equations were applied. A linear mixed effects model was used to compare the time effect of cortical thickness degeneration. The cognitive decline trajectory of the Aβ+ group was obvious, whereas the Aβ− and control groups did not exhibit a noticeable decline over time. The group effects of cortical thickness indicated decreased entorhinal cortex in the Aβ+ group and supramarginal gyrus in the Aβ− group. The topology of neurodegeneration in the Aβ− group was emphasized in posterior cortical regions. A comparison of the changes in the Aβ+ and Aβ− groups over time revealed a higher rate of cortical thickness decline in the Aβ+ group than in the Aβ− group in the default mode network. The Aβ+ and Aβ− groups experienced different APOE ε4 effects. For cortical–cognitive correlations, the regions associated with cognitive decline in the Aβ+ group were mainly localized in the perisylvian and anterior cingulate regions. By contrast, the degenerative topography of Aβ− MCI was scattered. The memory learning curves, cognitive decline patterns, and cortical degeneration topographies of the two MCI groups were revealed to be different, suggesting a difference in pathophysiology. Longitudinal analysis may help to differentiate between these two MCI groups if biomarker access is unavailable in clinical settings.     

Polycaprolactone/Chitosan Composite Nanofiber Membrane as a Preferred Scaffold for the Culture of Mesothelial Cells and the Repair of Damaged Mesothelium

Mesothelial cells are specific epithelial cells lining the serosal cavity and internal organs. Nonetheless, few studies have explored the possibility to culture mesothelial cells in a nanostructure scaffold for tissue engineering applications. Therefore, this study aims to fabricate nanofibers from a polycaprolactone (PCL) and PCL/chitosan (CS) blend by electrospinning, and to elucidate the effect of CS on the cellular response of mesothelial cells. The results demonstrate that a PCL and PCL/CS nanofiber membrane scaffold could be prepared with a comparable fiber diameter (~300 nm) and porosity for cell culture. Blending CS with PCL influenced the mechanical properties of the scaffold due to interference of PCL crystallinity in the nanofibers. However, CS substantially improves scaffold hydrophilicity and results in a ~6-times-higher cell attachment rate in PCL/CS. The mesothelial cells maintain high viability in both nanofiber membranes, but PCL/CS provides better maintenance of cobblestone-like mesothelial morphology. From gene expression analysis and immunofluorescence staining, the incorporation of CS also results in the upregulated expression of mesothelial marker genes and the enhanced production of key mesothelial maker proteins, endorsing PCL/CS to better maintain the mesothelial phenotype. The PCL/CS scaffold was therefore chosen for the in vivo studies, which involved transplanting a cell/scaffold construct containing allograft mesothelial cells for mesothelium reconstruction in rats. In the absence of mesothelial cells, the mesothelium wound covered with PCL/CS showed an inflammatory response. In contrast, a mesothelium layer similar to native mesothelium tissue could be obtained by implanting the cell/scaffold construct, based on hematoxylin and eosin (H&E) and immunohistochemical staining.     

Photo-Responsive Supramolecular Micelles for Controlled Drug Release and Improved Chemotherapy

Development of stimuli-responsive supramolecular micelles that enable high levels of well-controlled drug release in cancer cells remains a grand challenge. Here, we encapsulated the antitumor drug doxorubicin (DOX) and pro-photosensitizer 5-aminolevulinic acid (5-ALA) within adenine-functionalized supramolecular micelles (A-PPG), in order to achieve effective drug delivery combined with photo-chemotherapy. The resulting DOX/5-ALA-loaded micelles exhibited excellent light and pH-responsive behavior in aqueous solution and high drug-entrapment stability in serum-rich media. A short duration (1–2 min) of laser irradiation with visible light induced the dissociation of the DOX/5-ALA complexes within the micelles, which disrupted micellular stability and resulted in rapid, immediate release of the physically entrapped drug from the micelles. In addition, in vitro assays of cellular reactive oxygen species generation and cellular internalization confirmed the drug-loaded micelles exhibited significantly enhanced cellular uptake after visible light irradiation, and that the light-triggered disassembly of micellar structures rapidly increased the production of reactive oxygen species within the cells. Importantly, flow cytometric analysis demonstrated that laser irradiation of cancer cells incubated with DOX/5-ALA-loaded A-PPG micelles effectively induced apoptotic cell death via endocytosis. Thus, this newly developed supramolecular system may offer a potential route towards improving the efficacy of synergistic chemotherapeutic approaches for cancer.     

The study for dispatch decision of medical emergency resources with real-time spatial analysis

The Journal of Supercomputing - According to previous research, the most important factor for patient’s survival is based on the emergency treatment in the ambulance and the effective...