Genetic essentialism: On the deceptive determinism of DNA.

This article introduces the notion of genetic essentialist biases: cognitive biases associated with essentialist thinking that are elicited when people encounter arguments that genes are relevant for a behavior, condition, or social group. Learning about genetic attributions for various human conditions leads to a particular set of thoughts regarding those conditions: they are more likely to be perceived as (a) immutable and determined, (b) having a specific etiology, (c) homogeneous and discrete, and (d) natural, which can lead to the naturalistic fallacy. There are rare cases of “strong genetic explanation” when such responses to genetic attributions may be appropriate; however, people tend to overweigh genetic attributions compared with competing attributions even in cases of “weak genetic explanation,” which are far more common. The authors reviewed research on people's understanding of race, gender, sexual orientation, criminality, mental illness, and obesity through a genetic essentialism lens, highlighting attitudinal, cognitive, and behavioral changes that stem from consideration of genetic attributions as bases of these categories. Scientific and media portrayals of genetic discoveries are discussed with respect to genetic essentialism, as is the role that genetic essentialism has played (and continues to play) in various public policies, legislation, scientific endeavors, and ideological movements in recent history. Last, moderating factors and interventions to reduce the magnitude of genetic essentialism, which identify promising directions to explore in order to reduce these biases, are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Multi-GPU performance of incompressible flow computation by lattice Boltzmann method on GPU cluster

GPGPU has drawn much attention on accelerating non-graphic applications. The simulation by D3Q19 model of the lattice Boltzmann method was executed successfully on multi-node GPU cluster by using CUDA programming and MPI library. The GPU code runs on the multi-node GPU cluster TSUBAME of Tokyo Institute of Technology, in which a total of 680 GPUs of NVIDIA Tesla are equipped. For multi-GPU computation, domain partitioning method is used to distribute computational load to multiple GPUs and GPU-to-GPU data transfer becomes severe overhead for the total performance. Comparison and analysis were made among the parallel results by 1D, 2D and 3D domain partitionings. As a result, with 384 × 384 × 384 mesh system and 96 GPUs, the performance by 3D partitioning is about 3-4 times higher than that by 1D partitioning. The performance curve is deviated from the idealistic line due to the long communicational time between GPUs. In order to hide the communication time, we introduced the overlapping technique between computation and communication, in which the data transfer process and computation were done in two streams simultaneously. Using 8-96 GPUs, the performances increase by a factor about 1.1-1.3 with a overlapping mode. As a benchmark problem, a large-scaled computation of a flow around a sphere at Re = 13,000 was carried on successfully using the mesh system 2000 × 1000 × 1000 and 100 GPUs. For such a computation with 2 Giga lattice nodes, 6.0 h were used for processing 100,000 time steps. Under this condition, the computational time (2.79 h) and the data communication time (3.06 h) are almost the same.     

Evidence for compliance controlled oxygen vacancy and metal filament based resistive switching mechanisms in RRAM

We present electrical evidence on asymmetric metal-insulator-semiconductor (MIS) based test structures in support of the presence of two different independent switching mechanisms in a resistive random access memory (RRAM) device. The valid mechanism for switching depends on the compliance capping (I_gl) for forming/SET transition. Our results convincingly show that low compliance based switching only involves reversible oxygen ion drift to and from oxygen gettering gate electrodes, while high compliance switching involves formation and rupture of conductive metallic nanofilaments, as verified further by our physical analysis investigations. We have observed this unique dual mode switching mechanism only in NiSi-based gate electrodes, which have a moderate oxygen solubility as well as relatively low melting point.     

The initial stage of high‐pressure induced β‐lactoglobulin aggregation: the long‐run simulation

Research objective of this study was to clarify how the initial stage of high‐pressure induced aggregation of β‐lactoglobulin takes place. For this purpose a special simulation method was developed. Distinctive features of this approach are: the lowest resolution model of protein particles, the local interaction potential and the abandonment of the continuous simulation of particle trajectories. Relatively short molecular dynamics trajectories are used only in order to find the average time step between the collisions. Results of particle collisions that occur with some probability, are separately (‘statically’) modelled using a random variable. This allows the analysis of the process which takes place within 10²–10³ s real‐time, with an existing probability of successful collision of 10^?10–10^?11. Modelling results confirm that at the initial stage of aggregation of 0.5–2% solutions with a neutral pH‐value only dimers as well as trimers arise due to SH/S–S interaction. In addition it was shown that aggregation follows the general principles of the reaction‐limited aggregation of colloids. The proposed approach could further be used in research projects examining the aggregation of β‐lactoglobulin or similar systems.     

TD-SCDMA集群系统中部分宏分集组网前向容量分析

TD-SCDMA集群小区使用宏分集技术可以有效的克服大尺度衰落,保证信号质量。本文首先分析了在没有任何措施的前提下进行宏分集组网,但前向容量会随着宏分集基站数的增多而减少。在分析容量损失原因的基础上,我们进一步提出在终端利用Rake接收机对各路信号进行同步、相位调整,再进行最大比值合并,然后发送给用户,由此,前向容量大大提高。     

Temporal transitions in participation flow in an asynchronous discussion forum

This study examined the overarching issue of how temporal transitions, specifically duration of message flow, affects momentum or wellness of discussion in an asynchronous forum. Quantitative data representing time indicators in discussion activity included posting patterns related to duration (density, intensity, latency, and response count), Day-In topic, day of week, and time of day. Qualitative analysis identified notable spikes or irregularities (i.e., peaks and valleys) in the content level of postings. Results revealed that for open-ended topics (i.e., no specific end date imposed by the instructor), the momentum of forum discussion may be short-term, between 21 and 28 days into the topic. Peaks and valleys subsequent to 31 days were not significant to discussion vitality. Students posted mainly early to mid-week. Time of day had no direct influence on the vitality of the discussion. Strategies for applying temporal transitions in an online forum to motivate and sustain student participation are discussed.     

What do students do in a F2F CSCL classroom? The optimization of multiple communications modes

This exploratory study analyzes how students use different communication modes to share information, negotiate meaning and construct knowledge in the process of doing a group learning activity in a Primary Grade 5 blended learning environment in Singapore. Small groups of students interacted face-to-face over a computer-mediated communication (CMC) technology called Group Scribbles (GS) to jointly complete a learning task. The lesson designers attempted to optimize the use of CMC technology and face-to-face (F2F) discussion in students’ collaborative learning, with the aim of harnessing the specific features of each medium. Building on notions from communication studies and from interaction analysis, we observed the construction and evolution of the interactions through analyzing the artifacts that were produced by a group of students – in verbal talk, gestures, and sketches drawn and text inscribed in GS. F2F and GS interactions intertwined to support collaborative learning. The findings from this study could inform design aspects concerning integrating and reinforcing the strengths of both communication modes when introducing computer-assisted collaborative learning (CSCL) in a F2F classroom.     

Knowledge construction and misconstruction: A case study approach in asynchronous discussion using Knowledge Construction – Message Map (KCMM) and Knowledge Construction – Message Graph (KCMG)

This paper introduces a methodology for analyzing the knowledge construction and misconstruction processes occurring in online asynchronous discussion for Secondary 2 (Grade 8) students. The use of purposive sampling targeting specific students in a single course forum could potentially advance understanding of these processes using Knowledge Construction – Message Map (KCMM) and Knowledge Construction – Message Graph (KCMG). This paper traced the communication patterns and knowledge construction as well as misconstruction processes of students working in groups to formulate scientific ideas. This methodology reveals the dynamics of asynchronous discussion through mapping and quantifying the electronic learning process. This will equip educational practitioners and researchers with a useful tool for describing online interaction through adoption of a measurement methodology more systematic and effective than anecdotally. The research findings suggest that self-directed learning through asynchronous discussion has to be monitored by facilitators as learners possessed misconceptions that could potentially mislead other participants.     

Computer-mediated communication in adolescents with and without a history of specific language impairment (SLI)

The various uses of computer-mediated communication (CMC) are transforming the nature of social interactions and human relations among adolescents. Little is known about engagement of exceptional youth with this technology. The present study investigated the implications of language and social factors for frequency of CMC use and its relationship to adolescent well-being in young people with and without a history of specific language impairment (SLI). Eighty six adolescents with a history of SLI and 90 typically developing 17 year olds participated. Participants completed standardized assessments of psycholinguistic abilities and self-report measures of language motivations and social motivations for CMC use, as well as anxiety and depression. Results indicate that language abilities have a complex relationship with frequency of CMC use; social abilities have a more direct association and are predictive of frequency of CMC use. Both adolescents with SLI and typically developing adolescents were less shy online. No association was obtained between frequency of CMC use and reported emotional symptoms of anxiety and/or depression. It is argued that the characteristics of CMC, in terms of its less stringent language demands and its reduced-cues environment, can provide a medium for positive adaptation of adolescents with communication challenges.     

Net generation or Digital Natives: Is there a distinct new generation entering university?

This article reports key findings from the first phase of a research project investigating Net generation age students as they encounter e-learning at five universities in England. We take a critical view of the idea of a distinct generation which has been described using various terms including Net generation and Digital Natives and explore age related differences amongst first year university students. The article draws on evidence from a survey of first year undergraduates studying a range of pure and applied subjects. Overall we found a complex picture amongst first-year students with the sample population appearing to be a collection of minorities. These included a small minority that made little use of some technologies and larger minorities that made extensive use of new technologies. Often the use of new technology was in ways that did not fully correspond with the expectations that arise from the Net generation and Digital Natives theses. The article concludes that whilst there are strong age related variations amongst the sample it is far to simplistic to describe young first-year students born after 1983 as a single generation. The authors find that the generation is not homogenous in its use and appreciation of new technologies and that there are significant variations amongst students that lie within the Net generation age band.