Stimulus control of cocaine self-administration

Environmental stimuli that set the occasion wherein drugs are acquired can "trigger" drug-related behavior. Investigating the stimulus control of drug self-administration in laboratory animals should help us better understand this aspect of human drug abuse. Stimulus control of cocaine self-administration was generated here for the first time using multiple and chained schedules with short, frequently-alternating components--like those typically used to study food-maintained responding. The procedures and results are presented along with case histories to illustrate the strategies used to produce this stimulus control. All these multicomponent schedules contained variable-interval (VI) components as well as differential-reinforcement-of-other-behavior (DRO) or extinction components. Schedule parameters and unit dose were adjusted for each rat to produce stable, moderate rates in VI components, with minimal postreinforcement (infusion) pausing, and response cessation in extinction and DRO components. Whole-body drug levels on terminal baselines calculated retrospectively revealed that all rats maintained fairly stable drug levels (mean, 2.3 to 3.4 mg/kg) and molar rates of intake (approximately 6.0 mg/kg/hr). Within this range, no relation between local VI response rates and drug level was found. The stimulus control revealed in cumulative records was indistinguishable from that achieved with food under these schedules, suggesting that common mechanisms may underlie the control of cocaine- and food-maintained behavior.     

Twinning in bcc metals under shock loading: a challenge to empirical potentials

Using density functional theory (DFT), we found that high pressures intrinsically favor twinning in niobium by reducing the thickness of a stable twin. Five empirical interatomic potentials for niobium were considered in molecular dynamics (MD) shock simulations. The results show that two potentials exhibit the experimentally observed twinning behavior. Comparing with DFT under high pressure, we found that these two potentials are capable of reproducing the generalized stacking fault (GSF) curve, but the others predict several artificial metastable states along the GSF curve resulting in an artificial structural transformation.     

锁定加压钢板联合自体骨治疗非感染性股骨骨不连的疗效观察

观察锁定加压钢板联合植骨对非感染性股骨骨不连的临床疗效.回顾性分析2010年~2012年收治的31例非感染性股骨骨不连患者的临床资料.结果29例愈合,2例未完全愈合,本组愈合时间6个月~14个月,平均愈合时间6.9个月;术后均无感染、下肢成角、缩短畸形等并发症,手术前后髋、膝关节功能评分差异具有统计学意义（P＜0.05）.锁定加压钢板联合自体骨治疗非感染性股骨骨不连可获得牢固连接,并发症少,是临床治疗股骨骨不连的有效方法之一.     

Facial expressions and the ability to recognize emotions from the eyes or mouth: A comparison among old adults,young adults,and children

The aim of the present study was to contribute to the literature on the ability to recognize anger, happiness, fear, surprise, sadness, disgust, and neutral emotions from facial information (whole face, eye region, mouth region). More specifically, the aim was to investigate older adults' performance in emotions recognition using the same tool used in the previous studies on children and adults’ performance and verify if the pattern of emotions recognition show differences compared with the other two groups. Results showed that happiness is among the easiest emotions to recognize while the disgust is always among the most difficult emotions to recognize for older adults. The findings seem to indicate that is more easily recognizing emotions when pictures represent the whole face; compared with the specific region (eye and mouth regions), older participants seems to recognize more easily emotions when the mouth region is presented. In general, the results of the study did not detect a decay in the ability to recognize emotions from the face, eyes, or mouth. The performance of the old adults is statistically worse than the other two groups in only a few cases: in anger and disgust recognition from the whole face; in anger recognition from the eye region; and in disgust, fear, and neutral emotion recognition from mouth region.     

高频超声对膝关节病变的观察

通过超声对髌上囊、股骨髁间软骨情况、胭窝滑囊、髌腱等膝部结构的观察,评价超声对膝关节病变的辅助诊断、观察疗效的价值。通过高频超声对膝关节肿胀、疼痛病例纽与对照组、病例组治疗前后髌上囊液体、滑膜、股骨髁间软骨、胭窝滑囊积液情况以及髌腱厚度及回声进行对比观察。病例组髌上囊液体及滑膜增厚,股骨髁间软骨多有不同程度改变,胭窝滑...     

人工全膝关节置换术后持续被动运动的早期临床效果研究

探讨持续被动运动用于人工全膝关节置换术后的早期疗效。自2008年至2010年我科共完成人工全膝关节置换术36例（43膝）,将全部病例随机分为2组,A组术后单纯应用物理治疗及自身锻炼,B组采用持续被动锻炼加主动锻炼。观察术后12小时、24小时引流量,术后1周、2周膝关节主动活动范围,切口拆线时间,患者平均住院时间。术后2...     

运算动量效应的理论解释及其发展性预测因素

了解运算偏差的形成与发展对探索算数运算系统的内在机制具有重要意义,早期的算数运算能力是儿童理解和进行复杂数学运算的基础。运算动量偏差是指个体在进行基本数学运算时倾向于高估加法运算结果而低估减法运算结果的一种运算偏差,主要包括三种理论解释,即注意转移假说、启发式解释和压缩解释。鉴于运算动量效应在成年群体中相对稳定却在不同发展阶段儿童中存在不一致的证据,数学能力的提高与空间注意的成熟可结合不同的理论解释来阐明儿童发展过程中运算动量效应的变化趋势。未来可以进一步整合多种研究任务以揭示运算动量效应的发展轨迹,考察数量表征系统与运算动量效应间的关联,探究运算动量效应在不同运算符号中的稳定性,探讨不同因素共同作用对运算动量效应的影响,并设计有关数学能力的干预措施以减少运算动量效应这一运算偏差。     

Neutrosophic data formation using Gaussian filter based costas coding for wireless communication systems

Outstanding advantages of OFDM helps high data rate communication systems such as Digital Video Broadcasting (DVB) and mobile worldwide interoperability for microwave access (mobile Wi-MAX). But, OFDM system grieves from grave issue of high PAPR. In OFDM system data output is superposition of multiple sub-carriers and leads to big data. In this case some instantaneous power output might increase greatly and become far higher than the mean power of system. In order to make Neutrosophic data for less PAPR criteria, Gaussian filter based Costas coding is proposed. This paper also proposes feeding the Orthogonal Frequency Division Multiplexed signal (OFDM) into a phase accumulator to obtain frequency modulation, with the aim of reducing the peak to average power ratio (PAPR). For associated radar with modulated waveform mentioned here can be used to enhance the performance. It is widely used to analyze the variation of the output waveform further, the implementation results using MATLAB show that the ratio of average power to peak power is reducing considerably in comparing with the conventional method. Consequently; the signal can assume to fade in a frequency selective channel without an equalizer.