Validity of the Web-based, Self-directed, NeuroCognitive Performance Test in MCI

Digital cognitive tests offer several potential advantages over established paper-pencil tests but have not yet been fully evaluated for the clinical evaluation of mild cognitive impairment. The NeuroCognitive Performance Test (NCPT) is a web-based, self-directed, modular battery intended for repeated assessments of multiple cognitive domains. Using a sample of 101 MCI subjects, we report in this study that the NCPT composite is significantly correlated with both a composite measure of established tests (r=0.77, p<0.0001) as well as with the ADAS-Cog (r=0.55, p<0.0001). Both test batteries had a similar factor structure that included a large g component with a high eigenvalue. Further, both the NCPT and established tests significantly (p< 0.01) predicted the UPSA and FAQ, measures of daily functioning. Despite limitations such as a relatively small sample, absence of control group and cross-sectional nature, these findings are consistent with the growing literature on the promise of self-directed, web-based cognitive assessments for MCI. Key words: Alzheimers disease, computerized cognitive tests, clinical trials, NCPT

Measuring Attitude Towards Chemistry, Biology, and Math at a Hispanic-Serving Institution

This work describes the evaluation of the Attitude toward the Subject of Chemistry Inventory (ASCI), as well as two modifications (one for measuring attitude toward math and one for measuring attitude toward biology), for college students at a Hispanic Serving Institution. Instrument reliability was tested via multiple administrations of the instruments,and confirmatory factor analysis supported a two-factor structure similar to an existing model of a revised version of the ASCI for all three instruments. The similar factor structure of the three instruments, coupled with interviews with students, provide validity evidence for the instruments and support an interpretation that one of the subscales aligns with a cognitive aspect of attitude while the other subscale aligns with an affective aspect. The results of these instruments indicate that students have a more positive attitude towards biology than either chemistry or math, and more positive affective attitude than cognitive attitude for all three subjects, although student attitudes show little change with respect to biology, chemistry, or math during a typical semester. However, major perturbations, such as switching to remote instruction mid-semester, can lead to small but significant increases and decreases in attitude.

Data Mining Anthropometric Parameters for the Design and Sizing of Female Full Body Protector

Since the entry of female troops in different paramilitary forces, there is a dearth of well-fitted personal protective gear for them to maximise operational safety and protection. A mismatch of anthropometry in design adversely affected the user’s performance during critical operation, compromising the safety and well-being of an individual. A detailed anthropometry-based sizing study was conducted by the research team, on the Indian female paramilitary troops for proper sizing of their protective gears and ensembles. An anthropometric survey of 325 female para-military troops, posted in two locations with age ranged from 21 to 54 years (mean ± SD) value: 37.14 ± 8.49 years was done. Each subject’s 28 different body dimensions were taken. The data was then investigated using the factor analysis method. Principal component analysis technique was used to reduce the variables to similar factor components where, two components with an Eigenvalue of more than 1 were selected. viz. Principal component 1 (girth dimensions) and Principal component 2 (abdomen or waist dimension). These two key variables were used to divide the population into three separate clusters using the K-means cluster method. These cluster groups were validated using a regression tree. Descriptive statistical analysis of data was conducted followed by Cluster analysis (of key components shortlisted) using Statistical Product and Service Solution (SPSS) version 21. The current study was the first complete anthropometric survey of Indian female paramilitary personnel for the development of a female-specific sizing system for a full-body protector (FBP) design resulting is an improved fit of full-body protector.

Rapid Multimodal Image Registration Based on the Local Edge Histogram

Due to significant differences in imaging mechanisms between multimodal images, registration methods have difficulty in achieving the ideal effect in terms of time consumption and matching precision. Therefore, this paper puts forward a rapid and robust method for multimodal image registration by exploiting local edge information. The method is based on the framework of SURF and can simultaneously achieve real time and accuracy. Due to the unpredictability of multimodal images’ textures, the local edge descriptor is built based on the edge histogram of neighborhood around keypoints. Moreover, in order to increase the robustness of the whole algorithm and maintain the SURF’s fast characteristic, saliency assessment of keypoints and the concept of self-similar factor are presented and introduced. Experimental results show that the proposed method achieves higher precision and consumes less time than other multimodality registration methods. In addition, the robustness and stability of the method are also demonstrated in the presence of image blurring, rotation, noise, and luminance variations.

A Test of the Revised Minkov-Hofstede Model of Culture: Mirror Images of Subjective and Objective Culture across Nations and the 50 US States

Various models of subjective culture (measures of self-reports) have been proposed since Hofstede’s original work but none of them have been validated by showing that they have analogs in objective culture (measures of societal practices). Inspired by Bardi and Schwartz’s discovery that Schwartz’s individual-level circumplex values model has an exact equivalent in a model of behaviors, we develop a test for the purpose of validating models of culture. We apply this test to Minkov’s revised two-dimensional variant of Hofstede’s subjective-culture model, consisting of individualism-collectivism (IDV-COLL) and flexibility-monumentalism (FLX-MON) (formerly “long-term orientation”), as Fog recently found that an analog to this model incorporates and summarizes all major validated models and dimensions of national culture. We analyze national measures of important social practices associated empirically and theoretically with IDV-COLL and FLX-MON: transparency-corruption, gender equality, political freedom, road death tolls, homicide rates, family structures, innovation rates, and educational effort and achievement. These yielded close analogs to IDV-COLL and FLX-MON, with similar factor structures across nations and across the 50 US states, explicable in terms of IDV-COLL, FLX-MON, and life-history strategy (LHS) theories. Thus, subjective culture structures have mirror images in objective culture structures. This provides validation for our test, for the Minkov-Hofstede two-dimensional model of culture, for the use of nations and some sub-national political entities as units of cultural analysis, as well as for IDV-COLL, FLX-MON, and LHS theories.

Validation of the Ambivalent Ageism Scale in China

Two studies were conducted to validate the Ambivalent Ageism Scale in China. In the first study, 474 Chinese adults (18-58) were asked to take the Chinese version of the AAS. EFA exhibited a similar factor solution as the original study, with high internal consistency and construct validity. Moreover, in a second study, 372 Chinese adults (18-85) took the AAS and provided their estimations of the similarities between their current and their past/future self via the SIC. Results indicated that all three factors of the SIC positively related to hostile ageism, whereas succession and identity positively related to benevolent ageism and consumption negatively related to it. Additionally, past self-continuity was positively associated with hostile ageism, and future self-continuity was negatively associated with it, but neither form was associated with benevolent ageism. These results further validate the AAS in China and also provide evidence for the uniqueness of benevolent ageism.

The effect of a magnetic field on the dynamics of debris discs around white dwarfs

ABSTRACT Observational estimates of the lifetimes and inferred accretion rates from debris discs around polluted white dwarfs are often inconsistent with the predictions of models of shielded Poynting–Robertson drag on the dust particles in the discs. Moreover, many cool polluted white dwarfs do not show any observational evidence of accompanying discs. This may be explained, in part, if the debris discs had shorter lifetimes and higher accretion rates than predicted by Poynting–Robertson drag alone. We consider the role of a magnetic field on tidally disrupted diamagnetic debris and its subsequent effect on the formation, evolution, and accretion rate of a debris disc. We estimate that magnetic field strengths greater than ∼10 kG may decrease the time needed for circularization and the disc lifetimes by several orders of magnitude and increase the associated accretion rates by a similar factor, relative to Poynting–Robertson drag. We suggest some polluted white dwarfs may host magnetic fields below the typical detectable limit and that these fields may account for a proportion of polluted white dwarfs with missing debris discs. We also suggest that diamagnetic drag may account for the higher accretion rate estimates among polluted white dwarfs that cannot be predicted solely by Poynting–Robertson drag and find a dependence on magnetic field strength, orbital pericentre distance, and particle size on predicted disc lifetimes and accretion rates.

Nicotine Dependence in Dual Users of Cigarettes and E-Cigarettes: Common and Distinct Elements

Introduction In a sample of dual users of cigarettes and electronic nicotine delivery systems (ENDS; e-cigarettes), we evaluated psychometric properties of ENDS versions of the Nicotine Dependence Syndrome Scale (NDSS), the brief Wisconsin Inventory of Smoking Dependence Motives (WISDM), and the Fagerström Test for Nicotine Dependence (FTND). Using the NDSS, we tested the hypothesis that there would be one common underlying factor of dependence across the cigarette and ENDS scales and other product-specific factors. Aims and Methods Adult dual users (N = 404) completed baseline cigarette and ENDS versions of the NDSS, WISDM, and FTND, and biweekly surveys of their smoking and vaping. Analyses included bifactor modeling, which helps to identify both a general and product-specific factor for each item, and exploratory factor analyses of the combined cigarette and ENDS NDSS items and examinations of concurrent and predictive validity. Results The bifactor model was not a good fit, suggesting the lack of one common underlying dependence factor. Factor analyses revealed separate, similar factors for both products, with only one factor (priority) showing overlap of cigarette and ENDS items. ENDS scales significantly predicted ENDS use over time, but not cigarette use. Cigarette scales did not predict ENDS use over time. Conclusions Although the cigarette and ENDS NDSS versions showed similar factor structure, there was not a primary common underlying factor reflecting drive or tolerance, but rather product-specific factors. The cigarette scales were not valid for predicting ENDS use. These results highlight the importance of separately assessing dependence for cigarettes and ENDS in dual users. Implications Although underlying dimensions of nicotine dependence may be similar for ENDS and cigarettes, separate, product-specific measures may be needed to understand differences in product-specific dependency and predict changes in use of each product over time.

Jet feedback and the photon underproduction crisis in simba

ABSTRACT We examine the impact of black hole jet feedback on the properties of the low-redshift intergalactic medium (IGM) in the simba simulation, with a focus on the Lyα forest mean flux decrement DA. Without jet feedback, we confirm the photon underproduction crisis (PUC) in which ΓH i at $z$ = 0 must be increased by 6 times over the Haardt & Madau value in order to match the observed DA. Turning on jet feedback lowers this discrepancy to ∼2.5 times, and additionally using the recent Faucher–Giguère background mostly resolves the PUC, along with producing a flux probability distribution function in accord with observations. The PUC becomes apparent at late epochs ($z \lesssim 1$) where the jet and no-jet simulations diverge; at higher redshifts simba reproduces the observed DA with no adjustment, with or without jets. The main impact of jet feedback is to lower the cosmic baryon fraction in the diffuse IGM from 39 per cent to 16 per cent at $z$ = 0, while increasing the warm-hot intergalactic medium (WHIM) baryon fraction from 30 per cent to 70 per cent; the lowering of the diffuse IGM content directly translates into a lowering of DA by a similar factor. Comparing to the older mufasa simulation that employs different quenching feedback but is otherwise similar to simba, mufasa matches DA less well than simba, suggesting that low-redshift measurements of DA and ΓH i could provide constraints on feedback mechanisms. Our results suggest that widespread IGM heating at late times is a plausible solution to the PUC, and that simba’s jet active galactic nucleus feedback model, included to quench massive galaxies, approximately yields this required heating.

Self-similar extrapolation of nonlinear problems from small-variable to large-variable limit

Complicated physical problems are usually solved by resorting to perturbation theory leading to solutions in the form of asymptotic series in powers of small parameters. However, finite, and even large values of the parameters, are often of main physical interest. A method is described for predicting the large-variable behavior of solutions to nonlinear problems from the knowledge of only their small-variable expansions. The method is based on self-similar approximation theory resulting in self-similar factor approximants. The latter can well approximate a large class of functions, rational, irrational, and transcendental. The method is illustrated by several examples from statistical and condensed matter physics, where the self-similar predictions can be compared with the available large-variable behavior. It is shown that the method allows for finding the behavior of solutions at large variables when knowing just a few terms of small-variable expansions. Numerical convergence of approximants is demonstrated.