生物符号学视域下的脑机传播研究

脑机传播是一种全新的突破传统符号系统的人类传播形态。本文首先从其技术逻辑出发,分析了脑机传播赖以构建的技术基础——脑机接口技术,并在此基础上分析了其基本传播模型。随后,综述了脑机传播的技术逻辑之演变,以及生物符号学等诸相关学科学者对脑机传播的文献论述,为后续进一步的理论分析而奠基。本文从认知神经科学与生物符号学相交叉的学科视角,深入分析了脑机传播形态下由生物学意义上的神经电化学信号发放与传导到传播学意义上的符号传播的内部建模与外部建模之机理。正是通过这种内部建模与外部建模,使得神经元(物)与符号(心)之间实现了生物符号学意义下的内在融合,而意义在此中得以生成、创制、演绎、阐释及动态演化。

交叉学科视角下脑机传播本质及其特征探析

作为一种全新的人类传播形态,脑机传播突破了人类进化与基因所创制的外在符号系统,在生物脑与环境域之间实现了直接的信息交互。这种直接的信息交互的内在本质是什么?本文尝试了从生物符号学、认知神经科学、传播符号学、神经生理学等多学科交叉视角来解析,力图更加深刻、全面地揭示出这种全新的传播形态的内在本质及其特征,并为脑机传播学这一全新的学科领域的创立进行理论奠基。

直喷天然气发动机稀薄燃烧特性的仿真试验

在缸内直喷压缩天然气(Compressed natural gas,CNG)试验样机进行火焰传播特性可视化研究的基础上,仿真计算分析了不同喷射方式和不同点火方式对缸内浓度场、温度场等微观物理场的影响,以及这种微观物理场对NO生成规律的影响。结果表明:缸内浓度场的分布特性直接影响火焰传播速度和温度场,是控制稀薄燃烧过程的关键,可通过喷射方式来控制;点火方式主要改变温度场由此影响NO的生成规律;浓度梯度越大,火焰传播速度越快,稀薄燃烧稳定性越好;通过双点点火方式可以有效控制火焰传播速度。

基于智能体的音乐传播模型仿真分析

为了提高音乐传播效率,设计一种基于智能体的音乐传播模型,模型主要由音乐传播环境类、音乐传播智能体类两种智能体类构成。音乐传播智能体类的属性主要分为传播意愿程度、传播机率、再传播机率、传播次数和自身等级;音乐传播环境类的属性即为音乐传播智能体类的参与度。两种智能体类主要通过音乐信息传播交互规则实现音乐传播。研究发现,音乐信息价值越大,音乐传播智能体的数量越多,则音乐传播智能体间的音乐信息传播速度越快;音乐信息价值较大,传播群体的传播意愿程度也会出现明显的上升。与同类传播模型相比,基于智能体的音乐传播模型的传播效率较快,使用价值显著。

对血液透析病人和血透室工作人员感染HBV及HCV的调查

乙型肝炎病毒在肾病科通过血透机进行传播的资料国内已有报道。而丙型肝炎病毒通过此途径有较高的传播机率国外已经证实。本文就我院对血液透析患者和血透室工作人员对 HBV、HCV 定期检查的结果,以观察并进一步分析感染乙肝和丙肝的机率现报告如下。

网络时代最缺“有脑子”的记者

最近,一则报道让中国科学院"躺着中枪"。该院新闻办紧急发表声明称:某报就"2013全球腐败舆情表"相关新闻进行报道并表示"由中国科学院旗下的世研民意公司(CRC)代为调研"一事,经核查,中国科学院系统所属企业中无此公司,此信息有误。(《北京青年报》,7月15日)打开网络,类似的"辟谣"让人眼花缭乱,如坠云雾里。此前有消息称。

Analysis of the Current situation of Syphilis in a Sexually Transmitted Disease Clinic

Objective： To analyze the current situation of syphilis in the sexually transmitted diseases （STDs） clinic, from January 1994 to December 2002 was studied. Methods： All syphilis patients were confirmed by history, physical examination, dark-field microscopy of samples taken from the chancre or satellite lymph nodes,or positive serological tests. Results： From 1994 to 2002, there were 2067 cases of early syphilis, accounting for 20.01% （2067/10330） of all STD cases. The annual proportion of syphilis cases among all STD cases from 1994 to 2002 was 0.57%, 0.53%, 3.54%, 16.20%, 31.29%, 27.88%, 25.63%, 17.11%, 10.48%, respectively. Of 2067 syphilis patients,49.64% （1026/2067） were male and 50.36% （1041/2067） were female. 44.75% （925/2067） of all cases presented with primary syphilis, 44.90% （928/2067） with secondary syphilis, 9.77% （202/2067） with latent syphilis （without any conspicuous clinical signs or symptoms）, and 0.58% （12/2067） with congenital syphilis. The 30-39 year old cohort accounted for the largest proportion, at 37.68% （779/2067） of all syphilis cases. The 20-29 year old cohort also accounted for a large proportion, at 37.20% （769/2067） of all cases,followed by the 40-49 year old cohort, at 17.95% （371/2067）. Syphilis was most prevalent among the unemployed,self-employed laborers, and office workers in decreasing order. The majority of cases were graduates of either primary school, high school, or college. Of all syphilis cases, 87.86% （1816/2067） were married, and 12.14%（251/2067, including children） were unmarried. 76.78% （1587/2067） of all cases were acquired through extramarital intercourse. 14.03% （290/2067） of cases were infected by their spouses. 0.58% （12/2067） of cases were due to vertical transmission. 8.61% （178） of cases were acquired through indirect contact. Conclusion： The proportion of syphilis infection among all STDs remained stable from 1994 to 1995,quickly and dramatically increased from 1996 to 1999,and then gradually tapered down from 2000 to 2002. The incidence of congenital syphilis infections increased throughout the study period.

上高县宣讲团:课堂地头双丰收

7月13日,宜春市上高县宣讲团在县农业农村局开讲,宣传贯彻习近平总书记“七一”重要讲话精神,引导农业干部“学得进、记得牢、用得上”,让听众成为“宣传员”和“传播机”,促进全县乡村掀起学习“七一”讲话精神的热潮。

自媒体时代呼唤思维变通

＂世界上一成不变的东西,只有‘任何事物都是在不断变化的’这条真理。＂这个世界从未停止过变化的脚步,而且是越来越快了。20世纪90年代,商业广告还是被电视等传统媒体主宰着;到了千禧年代,网站已成了汇聚信息的新焦点;而今,自媒体时代已悄然来到我们身边,这股力量正在影响着整个社会的进程,它打破了原来信息不对称的现状,也打破了电视、广播、报纸、杂志等传统媒体主宰传播的局面。

浅析现代养羊业防疫体系的建立

1现代养羊业与疫病流行的特点1.1集约化程度高,饲养密度大现代养羊业由过去的自然放牧向高密度、大规模、集约化饲养转变,羊只间接触频率增高,增大了对疫病的传播机率。1.2品种追求良种化,商品引进羊只流动性大为提高羊的品质,多地选择良种繁育体系对本地品种进行改良,由于种羊场羊群健康水平不整齐和商品代饲养场种群来源不固定,加之多渠道购买羊只,增加了输入性疫情发生的可能性。

Uplink Grant-Free Pattern Division Multiple Access (GF-PDMA) for 5G Radio Access

Massive machine type communication(m MTC) is one of the key application scenarios for the fifth generation mobile communication(5 G). Grant-free(GF) transmission can reduce the high signaling overhead in m MTC. Non-orthogonal multiple access(NMA) can support more users for m MTC than orthogonal frequency division multiple access(OFDMA). Applying GF transmission in NMA system becomes an active topic recently. The in-depth study on applying GF transmission in pattern division multiple access(PDMA), a competitive candidate scheme of NMA, is investigated in this paper. The definition, latency and allocation of resource and transmission mechanism for GF-PDMA are discussed in detail. The link-level and system-level evaluations are provided to verify the analysis. The analysis and simulation results demonstrate that the proposed GF-PDMA has lower latency than grant based PDMA(GB-PDMA), possesses strong scalability to confront collision and provides almost 2.15 times gain over GF-OFDMA in terms of supporting the number of active users in the system.

Analysis of wave propagation on human body based on stratified media model

Human body communication(HBC) is a promising near-field communication(NFC) method emerging in recent years. But existing theoretical models of HBC are too simple to simulate the wave propagation on human body. In this work, in order to clarify the propagation mechanism of electromagnetic wave on human body, a surface waveguide HBC theoretical model based on stratified media cylinder is presented. A numerical model analyzed by finite element method(FEM) is used for comparing and validating the theoretical model. Finally, results of theoretical and numerical models from 80 MHz to 200 MHz agree fairly well, which means that theoretical model can characterize accurate propagation mechanism of HBC signal. Meanwhile, attenuation constants derived from two kinds of models are within the range from 1.64 to 3.37, so that HBC signal can propagate effectively on human body. The propagation mechanism derived from the theoretical model is useful to provide design information for the transmitter and the modeling of the propagation channel in HBC.

Crack propagation mechanism of compression-shear rock under static-dynamic loading and seepage water pressure

To reveal the water inrush mechanics of underground deep rock mass subjected to dynamic disturbance such as blasting, compression-shear rock crack initiation rule and the evolution of crack tip stress intensity factor are analyzed under static-dynamic loading and seepage water pressure on the basis of theoretical deduction and experimental research. It is shown that the major influence factors of the crack tip stress intensity factor are seepage pressure, dynamic load, static stress and crack angle. The existence of seepage water pressure aggravates propagation of branch cracks. With the seepage pressure increasing, the branch crack experiences unstable extension from stable propagation. The dynamic load in the direction of maximum main stress increases type I crack tip stress intensity factor and its influence on type II crack intensity factor is related with crack angle and material property. Crack initiation angle changes with the dynamic load. The initial crack initiation angle of type I dynamic crack fracture is 70.5°. The compression-shear crack initial strength is related to seepage pressure, confining pressure, and dynamic load. Experimental results verify that the initial crack strength increases with the confining pressure increasing, and decreases with the seepage pressure increasing.

Local and global approaches of affinity propagation clustering for large scale data

Recently a new clustering algorithm called 'affinity propagation' (AP) has been proposed, which efficiently clustered sparsely related data by passing messages between data points. However, we want to cluster large scale data where the similarities are not sparse in many cases. This paper presents two variants of AP for grouping large scale data with a dense similarity matrix. The local approach is partition affinity propagation (PAP) and the global method is landmark affinity propagation (LAP). PAP passes messages in the subsets of data first and then merges them as the number of initial step of iterations; it can effectively reduce the number of iterations of clustering. LAP passes messages between the landmark data points first and then clusters non-landmark data points; it is a large global approximation method to speed up clustering. Experiments are conducted on many datasets, such as random data points, manifold subspaces, images of faces and Chinese calligraphy, and the results demonstrate that the two ap-proaches are feasible and practicable.

Dormant stages of crustaceans as a mechanism of propagation in the extreme and unpredictable environment in the Crimean hypersaline lakes

A pool of dormant stages of planktonic organisms in saline lakes is a substantial component in the plankton communities;we need to take it into account to understand plankton dynamics.Hypersaline water bodies in Crimea,the largest peninsula in the Black Sea,constitute a very characteristic and peculiar habitat type in the region.We examined the presence of crustacean resting stages in sediments of dried up sites of the Crimean hypersaline lakes.Sediment samples were taken in 9 different lakes.Experiments performed on the hatching of these resting stages showed the presence of Moina salina(Cladocera),parthenogenetic Artemia and Artemia urmiana(Anostraca),Eucypris mareotica( inflata)(Ostracoda),and Cletocamptus retrogressus(Harpacticoida).Comparing the experimental results obtained with clean dried brine shrimp cysts and those kept in sediment samples,it was noted that clean cysts hatched much faster than those from sediments did.Some components in bottom sediments slow down and desynchronize hatching from resting eggs in different groups of crustaceans.The sediments of different lakes inhibited the nauplii output from Artemia and ostracod resting eggs to different degrees.More data are needed before we can discuss the reasons of this inhibition.The nonsynchronous output of active stages from the bottom resting ones may be an adaptation that allows crustacean species to exist in extreme and unpredictably changing environments,avoiding the risk that all may emerge at once under unsuitable conditions.

Neoplasm-like abdominal nonhematogenous disseminated tuberculous lymphadenopathy: CT evaluation of 12 cases and literature review

AIM: To assess the diagnostic value of computed tomography (CT) imaging in screening for abdominal nonhematogenous disseminated tuberculous lymphadenopathy (TL). METHODS: The CT scans of 12 patients with abdominal nonhematogenous disseminated TL suggestive of neoplasm were retrospectively analyzed in this review. The final diagnoses were confirmed by lymph node pathology for seven patients and by laparoscopic surgery for five patients. All of the patients were treated at our institution between April 1995 and August 2009. RESULTS: The sites of involvement were the periportal (n = 6), peripancreatic (n = 3), periaortic (n = 3), and mesenteric (n = 2) regions. On the plain CT scan, the lymphadenopathy showed a heterogeneous isodensity or hypodensity in 11 patients and a low density in one patient. Peripheral enhancement was observed on the dynamic contrast-enhanced CT scans for all patients. In two cases, scans were more revealing during the portal venous and delayed phases. CONCLUSION: Abdominal lymphadenopathy with predominant peripheral rim-like enhancement on the dynamic contrast-enhanced CT scan may suggest a diagnosis of TL.

A randomized controlled clinical trial: Interruption of intrauterine transmission of hepatitis B virus infection with HBIG

AIM： To evaluate the efficacy of interruption of intrauterine infection of HBV with HBIG in pregnant women with positive HBeAg and HBsAg.METHODS： A prospective randomized controlled trial was adopted. Sixty cases with positive HBeAg and HBsAg were coincident with the criteria of inclusion, and 8 cases were excluded. Fifty-two cases were analyzed （28 cases in trial group and 24 in control group）. All cases in trial group received 200 IU HBIG intravenously every 4 wk for 3 times from the 28^th wk. The cases of control group received placebo in the same way. All pregnant women were detected for HBeAg and HBV-DNA at the beginning of the trial and end of the trial （delivery）. The cord blood of all newborns were collected for detecting HBeAg and HBV-DNA simultaneously.RESULTS： For investigation of HBeAg of newborns in trial group, 6 of 28 cases of newborns had positive HBeAg, the HBeAg positive rate being 21.4%, the total rate of 95% CI being 8%-41%. In control group, 19 of 24 cases of newborns had positive HBeAg, HBeAg positive rate was 79.2%, the rate of 95%CI being 5%-93%. By statistical analysis, 2= 17.26, P 〈 0.01, RR = 0.27, 95% CI （6.3 × 10^-6, 8.6 × 10^-5）. For investigation of HBV-DNA of newborns in trial group, 7 of 28 cases of newborns had positive HBV-DNA, HBV-DNA positive rate being 25%, the total rate of 95% CI being 11%-45%. In control group, 20 of 24 cases of newborns had positive HBV-DNA, HBV-DNA positive rate was 83.3%, the total rate of 95% CI being 63%-95%. By statistical analysis, X^2 = 17.62, P 〈 0.01, RR = 0.30, 95% CI （1.5 × 10^-5, 1.7× 10^-4）. The results indicated that there was significant difference in HBeAg positive rate and HBV-DNA positive rate of newborns between the two groups. In trial group, 7 of 28 newborns had HBV-DNA positive, but the HBV-DNA load of newborns was lower than that of their mothers. In control group, 20 of 24 newborns still had HBV-DNA positive, and the HBV-DNA load of newborns was close to those of their mothers. Statistical analysis indicated that there was no significant difference in HBV- DNA load between postnatal women without HBIG intervention and their filial generations （T = 81.5, P 〉 0.1）. CONCLUSION： It is effective and safe to prevent intrauterine infection of HBV with HBIG from the 28^th wk in pregnant women with positive HBeAg and HBsAg. In clinical application, those pregnant women with negative HBeAg and positive HBV-DNA also need to be interrupted by HBIG.

Cracks coalescence mechanism and cracks propagation paths in rock-like specimens containing pre-existing random cracks under compression

The mechanism of cracks propagation and cracks coalescence due to compressive loading of the brittle substances containing pre-existing cracks （flaws） was modeled experimentally using specially made rock-like specimens from Portland Pozzolana Cement （PPC）. The breakage process of the specimens was studied by inserting single and double flaws with different inclination angles at the center and applying uniaxial compressive stress at both ends of the specimen. The first crack was oriented at 50＆#176; from the horizontal direction and kept constant throughout the analysis while the orientation of the second crack was changed. It is experimentally observed that the wing cracks are produced at the first stage of loading and start their propagation toward the direction of uniaxial compressive loading. The secondary cracks may also be produced in form of quasi-coplanar and/or oblique cracks in a stable manner. The secondary cracks may eventually continue their propagation in the direction of maximum principle stress. These experimental works were also simulated numerically by a modified higher order displacement discontinuity method and the cracks propagation and cracks coalescence were studied based on Mode I and Mode II stress intensity factors （SIFs）. It is concluded that the wing cracks initiation stresses for the specimens change from 11.3 to 14.1 MPain the case of numerical simulations and from 7.3 to 13.8 MPa in the case of experimental works. It is observed that cracks coalescence stresses change from 21.8 to 25.3 MPa and from 19.5 to 21.8 MPa in the numerical and experimental analyses, respectively. Comparing some of the numerical and experimental results with those recently cited in the literature validates the results obtained by the proposed study. Finally, a numerical simulation was accomplished to study the effect of confining pressure on the crack propagation process, showing that the SIFs increase and the crack initiation angles change in this case.

Energy-Efficient Sensing and Transmission for Multi-Hop Relay Cognitive Radio Sensor Networks

How to achieve transmissions in an energy-efficient way in multi-hop decode and forward(DF) relay cognitive radio sensor networks(CRSNs) is important since sensor nodes in CRSNs are usually battery powered. This paper aims to maximize energy efficiency(EE) by joint optimizing sensing time and power allocation in multi-channels & multihops DF relay CRSNs under constraints on outage probability and sensing performance. First, we design a channel selection scheme for sensing according to the available probabilities of multi channels. Second, we analyze the expected throughput and energy consumption and formulate the EE problem as a concave/concave fractional program. Third, coordinate ascent and Charnes-Cooper Transformation(CCT) methods are used to transform the nonlinear fractional problem into an equivalent concave problem. Subsequently, the closed form of outage probability is derived and the convergence rate of the iterative algorithm is analyzed. Finally, simulation results show that the proposed scheme can achieve effective EE.

Multiple Mobile Sinks Data Dissemination Mechanism for Large Scale Wireless Sensor Network

WSN has been developing from traditional environment monitoring applications to the ubiquitous information services such as the Congestion-oriented Intelligent Transportation System （ColTS）. However, the mobility of nodes makes data dissemination a hard nut to crack. In this paper, we propose MSDD, a multiple mobile sinks data dissemination mechanism for solving the dissemination problem. The main ideas of MSDD are constructing a two-tier grid structure by a designated sink, exploiting a hierarchical monitoring mechanism, and employing a global agent to track the sink locations in order to make the emergencies reported to the sinks immediately, In addition, MSDD supports the query-driven data dissemination. Being compared with TTDD, MSDD is theoretically proved to have less communication overhead. We also validate MSDD outperforms TTDD in reliability and the emergency delivery latency bv simulations.