An examination of psychometric bias due to retesting on cognitive ability tests in selection settings.

Using a latent variable approach, the authors examined whether retesting on a cognitive ability measure resulted in measurement and predictive bias. A sample of 941 candidates completed a cognitive ability test in a high-stakes context. Results of both the within-group between-occasions comparison and the between-groups within-occasion comparison indicated that no measurement bias existed during the initial testing but that retesting induced both measurement and predictive bias. Specifically, the results suggest that the factor underlying the retest scores was less saturated with g and more associated with memory than the latent factor underlying initial test scores and that these changes eliminated the test's criterion-related validity. This study's implications for retesting theory, practice, and research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

充满信心地设计军用SDR产品

21世纪的战场以网络战为中心，从卫星到单兵，以及各种装备中，系统体积、重量和功耗（SWaP）都非常关键。不论是在有人（舰艇、飞机和车辆），还是无人（导弹、传感器，以及空中和地面车辆（UAV和UGV））装备中，保密无线通信都是各种方案关注的焦点。而且，在不同战场上，保密通信设备的三重业务（语音、视频和数据）功能和多兆位带宽设计是难度最大的。机载和海上软件无线电（SDR）设计遇到的挑战是功能和散热（制冷）问题，而SwaP应用最迫切的要求则是采用手持式、单兵携带和小外形（HMS）电池工作系统。     

Direct extraction of surface meshes from implicitly represented heterogeneous volumes

This paper describes a novel algorithm to extract surface meshes directly from implicitly represented heterogeneous models made of different constituent materials. Our approach can directly convert implicitly represented heterogeneous objects into a surface model separating homogeneous material regions, where every homogeneous region in a heterogeneous structure is enclosed by a set of two-manifold surface meshes. Unlike other discretization techniques of implicitly represented heterogeneous objects, the intermediate surfaces between two constituent materials can be directly extracted by our algorithm. Therefore, it is more convenient to adopt the surface meshes from our approach in the boundary element method (BEM) or as a starting model to generate volumetric meshes preserving intermediate surfaces for the finite element method (FEM). The algorithm consists of three major steps: firstly, a set of assembled two-manifold surface patches coarsely approximating the interfaces between homogeneous regions are extracted and segmented; secondly, signed distance fields are constructed such that each field expresses the Euclidean distance from points to the surface of one homogeneous material region; and finally, coarse patches generated in the first step are dynamically optimized to give adaptive and high-quality surface meshes. The manifold topology is preserved on each surface patch.     

A correct derivation of acceleration parameter for hopscotch and checkerboard (P,Q)-cyclic relaxation schemes

The correct method for applying the von Neumann stability analysis to composite finite difference schemes for numerical solution of partial differential equations is investigated. Our results provide justification of the hopscotch method and give correction to earlier analyses [1,7]. The methods employed here to analyze checkerboard and hopscotch iterative processes are also applicable to the study of more general composite (P, Q)-cyclic finite difference schemes.     

A split Band-Cholesky equation solving strategy for finite element analysis of transisent field problems

An efficient strategy is outlined for out-of-core solution of the large systems of equations which specify nodal point time derivatives in finite element models of transient flow problems. The positive definiteness, symmetry, and band structure of the finite element mass matrices, as well as the nature of the equation assemblage process, is exploited by the method. Computational results are indicated for systems on the order of several thousand unknowns in size.     

Forced-choice assessments of personality for selection: Evaluating issues of normative assessment and faking resistance.

Recent research suggests multidimensional forced-choice (MFC) response formats may provide resistance to purposeful response distortion on personality assessments. It remains unclear, however, whether these formats provide normative trait information required for selection contexts. The current research evaluated score correspondences between an MFC format measure and 2 Likert-type measures in honest and instructed-faking conditions. In honest response conditions, scores from the MFC measure appeared valid indicators of normative trait standing. Under faking conditions, the MFC measure showed less score inflation than the Likert measure at the group level of analysis. In the individual-level analyses, however, the MFC measure was as affected by faking as was the Likert measure. Results suggest the MFC format is not a viable method to control faking. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A contingent view of reactions to objective pay conditions: Interdependence among pay structure characteristics and pay relative to internal and external referents.

The authors studied the general proposition that because social comparisons are so central to how people react to pay, the effect of an important pay condition likely depends on a social pay comparison that is relevant to that condition. To investigate this, the authors used actual pay data on more than 2,000 public school teachers across more than 400 school districts and tested whether pay equity perceptions resulted from interactions among objective measures of structural (pay dispersion, entry-level pay, pay range maximum, external competitiveness) and individual (pay relative to internal referents, pay relative to external referents) pay conditions. Cross-level interactions indicated that pay relative to internal referents moderated how pay structure conditions related to pay equity perceptions. Additionally, within-level interactions indicated that the effect of employee standing in the external pay hierarchy depended on where one stood in the internal pay hierarchy; this dynamic emerged both for individual-level measures of current standing and for organization-level measures that suggested future standing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The identification of functional regions: theory, methods, and applications

A functional region is characterised by a high frequency of intra-regional interaction. The text analyses how functional regions can be identified by using labour market data. Three approaches are applied in this task, named the local labour market, commuting zone, and accessibility approach, respectively. The text includes an application using the Fyrstad region. The situation is also studied at two points in time. The outcomes using the different approaches are compared, and the results combined have a richer flavour.

Trichodermin Induces G0/G1 Cell Cycle Arrest by Inhibiting c-Myc in Ovarian Cancer Cells and Tumor Xenograft-Bearing Mice

Ovarian cancer is a fatal gynecological cancer because of a lack of early diagnosis, which often relapses as chemoresistant. Trichodermin, a trichothecene first isolated from Trichoderma viride, is an inhibitor of eukaryotic protein synthesis. However, whether trichodermin is able to suppress ovarian cancer or not was unclear. In this study, trichodermin (0.5 µM or greater) significantly decreased the proliferation of two ovarian cancer cell lines A2780/CP70 and OVCAR-3. Normal ovarian IOSE 346 cells were much less susceptible to trichodermin than the cancer cell lines. Trichodermin predominantly inhibited ovarian cancer cells by inducing G0/G1 cell cycle arrest rather than apoptosis. Trichodermin decreased the expression of cyclin D1, CDK4, CDK2, retinoblastoma protein, Cdc25A, and c-Myc but showed little effect on the expression of p21^Waf1/Cip1, p27^Kip1, or p16^Ink4a. c-Myc was a key target of trichodermin. Trichodermin regulated the expression of Cdc25A and its downstream proteins via c-Myc. Overexpression of c-Myc attenuated trichodermin’s anti-ovarian cancer activity. In addition, trichodermin decelerated tumor growth in BALB/c nude mice, proving its effectiveness in vivo. These findings suggested that trichodermin has the potential to contribute to the treatment of ovarian cancer.     

Assessment of the N-nitrosopiperidine formation risk from piperine and piperidine contained in spices used as meat product additives

The N-nitrosopiperidine (NPIP) formation in blends of spices and nitrite curing salt was investigated in relation with the piperine and piperidine contents in spices. Firstly, two analytical methods were developed. Piperine was extracted with dichloromethane by means of accelerated solvent extraction (ASE) and determined by high-performance liquid chromatography (HPLC)–diode array detector (λ = 343 nm). A selective hydroextraction of piperidine using ASE and its quantification by HPLC–ELSD was applied. Both methods were sufficiently sensitive and accurate (limit of detection, limit of quantification, and recovery: 0.28, 0.84 μg, and 98.9 ± 2.6 % for piperine, and 5.76, 17.45 μg, and 95.9 ± 2.9 % for piperidine, respectively). Secondly, both compounds were quantified in commercial samples (black and white pepper, paprika, chili pepper, allspice, and nutmeg). The maximum amount of piperine (21.12 mg g^?1) was found in pepper, while the other spices contained only traces. Piperidine was detected mainly in the pepper samples, whereby the highest concentration was found in the white pepper extract (11.42 mg g^?1). Thirdly, during the storage of spices blended with nitrite curing salt, the NPIP content was determined, using a gas chromatograph coupled with a thermal energy analyzer. Against our expectations, no NPIP formation was observed in the curing mixture which contained white pepper extract. This result remains in contrast with the white pepper mixture, in which the NPIP content significantly increased from not detected to 9.80 ± 0.41 ng g^?1 after the 2 months storage period. In conclusion, high amounts of piperine or piperidine in spices do not systematically result in the formation of NPIP, when blended with nitrite curing salt .