Contraction intensity and velocity on vastus lateralis SEMG power spectrum and amplitude

Effect of contraction intensity [100%, 75%, 50%, and 25% maximum voluntary contraction (MVC)] and movement velocity [0 degrees (isometric)], 50 degrees, 100 degrees, 200 degrees, and 400 degrees/sec. [isovelocities]) on root mean square amplitude (SEMG-RMS) and median frequency power spectrum (SEMG-MNF) of vastus lateralis (VL) surface electromyography was investigated with ten healthy female university students. Peak torque (PT), mean torque (MT), SEMG-MNF, and SEMG-RMS, analyzed using separate repeated-measures analyses of variance (p < or = .05), indicated: (1) an inverse relation between PT and MT and movement velocity, (2) greater SEMG-MNF values during all isovelocity conditions compared with isometric conditions, with highest values occurring at 50 degrees /sec. and at 100% and 75% MVC, and (3) at all contraction intensities SEMG-RMS values were higher during dynamic movements than isometric movements and highest at 200 degrees /sec. Isovelocity contractions were inferred to facilitate a greater recruitment of fast-twitch fibers (via increased SEMG-MNF), which was intensified at 50 degrees /sec., whereas greater overall muscle activation was found at 200 degrees /sec.     

Self-other rating agreement and leader-member exchange (LMX): a quasi-replication

Data from a sample of 83 elected community leaders and 391 direct-report staff (resulting in 333 useable leader-member dyads) were reanalyzed to test relations between self-other rating agreement of servant leadership and member-reported leader-member exchange (LMX). Polynomial regression analysis indicated that the self-other rating agreement model was not statistically significant. Instead, all of the variance in member-reported LMX was accounted for by the others' ratings component alone.     

Evidence for the Effectiveness of an Alternative Multisource Performance Rating Methodology

Despite persistent concerns as to the quality of performance information obtained from multisource performance ratings (MSPRs), little research has sought ways to improve the psychometric properties of MSPRs. Borrowing from past methodologies designed to improve performance ratings, we present a new method of presenting items in MSPRs, frame‐of‐reference scales (FORS), and test the efficacy of this method in a field and lab study. The field study used confirmatory factor analysis to compare the FORS to traditional rating scales and revealed that FORS are associated with increased variance due to dimensions, decreased overlap among dimensions, and decreased error. The laboratory study compared rating accuracy associated with FORS relative to frame‐of‐reference training (FORT) and a control group and demonstrated that FORS are associated with higher levels of accuracy than the control group and similar levels of accuracy as FORT. Implications for the design and implementation of FORS are discussed.     

Fine-tuning and the infrared bull’s-eye

I argue that the standard way of formalizing the fine-tuning argument for design is flawed, and I present an alternative formalization. On the alternative formalization, the existence of life is not treated as the evidence that confirms design; instead it is treated as part of the background knowledge, while the fact that fine tuning is required for life serves as the evidence. I argue that the alternative better captures the informal line of thought that gives the fine-tuning argument its intuitive plausibility, and I show that the alternative formalization avoids all of the most prominent objections to the fine-tuning argument, including the objection from observation selection effects, the problem of old evidence, the problem of non-normalizable probability measures and a further objection due to Monton. I conclude that the alternative formalization is the one that attention should be focused on.     

Non-target language processing in Chinese-English bilinguals: a study of event-related potential

The event-related brain potential (ERP) technique was used to investigate the neural mechanism of non-target language processing in Chinese-English bilinguals. Participants were presented with a mixed list of Chinese and English words and required to make conceptual decisions for words in one language and ignore words in the other non-target language. Regardless of whether the nontarget word was in Chinese or English, the ERPs they elicited were modulated by word frequency, suggesting that their meaning had been accessed. The N400 peak was delayed in the English as the non-target language condition, probably because participants were less proficient in English. The results suggest that the non-target language can be processed during conceptual tasks with participants' proficiency in this language being a critical factor.     

Is knowledge justified true belief?

Is knowledge justified true belief? Most philosophers believe that the answer is clearly ‘no’, as demonstrated by Gettier cases. But Gettier cases don’t obviously refute the traditional view that knowledge is justified true belief (JTB). There are ways of resisting Gettier cases, at least one of which is partly successful. Nevertheless, when properly understood, Gettier cases point to a flaw in JTB, though it takes some work to appreciate just what it is. The nature of the flaw helps us better understand the nature of knowledge and epistemic justification. I propose a crucial improvement to the traditional view, relying on an intuitive and independently plausible metaphysical distinction pertaining to the manifestation of intellectual powers, which supplements the traditional components of justification, truth and belief.     

Physico-mathematics and the search for causes in Descartes’ optics—1619–1637

One of the chief concerns of the young Descartes was with what he, and others, termed “physico-mathematics”. This signalled a questioning of the Scholastic Aristotelian view of the mixed mathematical sciences as subordinate to natural philosophy, non explanatory, and merely instrumental. Somehow, the mixed mathematical disciplines were now to become intimately related to natural philosophical issues of matter and cause. That is, they were to become more ’physicalised’, more closely intertwined with natural philosophising, regardless of which species of natural philosophy one advocated. A curious, short-lived yet portentous epistemological conceit lay at the core of Descartes’ physico-mathematics—the belief that solid geometrical results in the mixed mathematical sciences literally offered windows into the realm of natural philosophical causation—that in such cases one could literally “see the causes”. Optics took pride of place within Descartes’ physico-mathematics project, because he believed it offered unique possibilities for the successful vision of causes. This paper traces Descartes’ early physico-mathematical program in optics, its origins, pitfalls and its successes, which were crucial in providing Descartes resources for his later work in systematic natural philosophy. It explores how Descartes exploited his discovery of the law of refraction of light—an achievement well within the bounds of traditional mixed mathematical optics—in order to derive—in the manner of physico-mathematics—causal knowledge about light, and indeed insight about the principles of a “dynamics” that would provide the laws of corpuscular motion and tendency to motion in his natural philosophical system.