Anticipating ankle inversion perturbations during a single-leg drop landing alters ankle joint and impact kinetics

Anticipatory responses to inversion perturbations can prevent an accurate assessment of lateral ankle sprain mechanics when using injury simulations. Despite recent evidence of the anticipatory motor control strategies utilized during inversion perturbations, kinetic compensations during anticipated inversion perturbations are currently unknown. The purpose of this investigation was to examine the influence of anticipation to an inversion perturbation during a single-leg drop landing on ankle joint and impact kinetics. Fifteen young adults with no lateral ankle sprain history completed unanticipated and anticipated single-leg drop landings onto a 25° laterally inclined platform from a height of 30 cm. One-dimensional statistical parametric mapping (SPM) was used to analyze net ankle moments and ground reaction forces (GRF) during the first 150 ms post-landing, while peak GRFs, time to peak GRF, peak and average loading rates were compared using a dependent samples t-test (p ≤ 0.05). Results from the SPM analysis revealed significantly greater plantar flexion moment from 58 to 83 ms post-landing (p = 0.004; d = 0.64–0.77), inversion moment from 89 to 91 ms post-landing (p = 0.050; d = 0.58–0.60), and medial GRF from 62 to 97 ms post-landing (p < 0.001; d = 1.00–2.39) during the unanticipated landing condition. Moreover, significantly greater peak plantarflexion (p < 0.001; d = 1.10) and peak inversion moment (p = 0.007; d = 0.94), as well as greater peak (p = 0.002; d = 1.03) and average (p = 0.042; d = 0.66) medial loading rates, were found during the unanticipated landing condition. Our findings suggest alterations to ankle joint and impact kinetics occur during a single-leg drop landing when inversion perturbations are anticipated. Researchers and practitioners using drop-landings onto a tilted surface to assess lateral ankle sprain injury risk should consider implementing protocols that mitigate anticipatory responses.     

Newborns are sensitive to multiple cues for word segmentation in continuous speech

Before infants can learn words, they must identify those words in continuous speech. Yet, the speech signal lacks obvious boundary markers, which poses a potential problem for language acquisition (Swingley, Philos Trans R Soc Lond. Series B, Biol Sci 364 (1536), 3617–3632, 2009). By the middle of the first year, infants seem to have solved this problem (Bergelson & Swingley, Proc Natl Acad Sci 109 (9), 3253–3258, 2012; Jusczyk & Aslin, Cogn Psychol 29 , 1–23, 1995), but it is unknown if segmentation abilities are present from birth, or if they only emerge after sufficient language exposure and/or brain maturation. Here, in two independent experiments, we looked at two cues known to be crucial for the segmentation of human speech: the computation of statistical co‐occurrences between syllables and the use of the language's prosody. After a brief familiarization of about 3 min with continuous speech, using functional near‐infrared spectroscopy, neonates showed differential brain responses on a recognition test to words that violated either the statistical (Experiment 1) or prosodic (Experiment 2) boundaries of the familiarization, compared to words that conformed to those boundaries. Importantly, word recognition in Experiment 2 occurred even in the absence of prosodic information at test, meaning that newborns encoded the phonological content independently of its prosody. These data indicate that humans are born with operational language processing and memory capacities and can use at least two types of cues to segment otherwise continuous speech, a key first step in language acquisition.     

基于名人面孔视觉特征和语义信息的视觉统计学习

视觉统计学习是指个体依据视觉刺激之间的转接概率来掌握统计规律的过程。本研究通过5个实验探讨了个体基于名人面孔视觉特征和语义信息进行视觉统计学习的加工机制。每个实验均包括熟悉(学习)和测试两个阶段：在熟悉阶段, 让被试观看名人面孔并完成重复图片探测的无关任务; 在测试阶段, 让被试进行二选一迫选任务。其中, 实验1和2分别考察基于名人面孔视觉特征和语义信息的视觉统计学习效果; 实验3分别考察基于名人面孔视觉特征和语义信息视觉进行统计学习的精确性; 实验4进一步考察基于名人面孔视觉特征和语义信息进行视觉统计学习的时间特征; 实验5验证基于名人面孔视觉特征的视觉统计学习具有面孔特异性。结果表明：个体能同时基于名人面孔视觉特征和语义信息进行精确的视觉统计学习; 基于正立名人面孔的视觉统计学习效果显著高于基于倒置名人面孔的视觉统计学习效果; 虽然基于视觉特征和语义信息的统计加工都具有一致的精确性, 但后者需要更多的加工时间。这提示：基于名人面孔视觉特征的视觉统计学习具有面孔特异性, 个体基于名人面孔视觉特征和语义信息的视觉统计学习过程是分离的, 统计运算发生于面孔特征加工完成之后。     

Lower limb mechanical asymmetry during repeated treadmill sprints

Stride mechanical imbalances between the lower limbs may be detrimental to performance and/or increase injury risks. This study describes the time course and magnitude of asymmetries in running mechanical variables during repeated treadmill sprints and examines whether inter-limb differences in sprinting mechanics increase with fatigue. Thirteen non-injured male athletes performed five 5-s sprints with 25-s recovery on an instrumented treadmill, allowing the continuous (step-by-step) measurement of running kinetics/kinematics and spring-mass characteristics calculation. For each variable, bilateral leg asymmetry (BLA%) between the left and the right leg was defined as: {[(high value − low value)/low value] × 100}. BLA% for propulsive power and horizontal forces averaged ∼12–13%, while lower values occurred for step-averaged values of running velocity, resultant and vertical forces (all ∼4%). For all sprints, kinematic BLA% ranged from 1.6 ± 1.0% (swing time) to 9.0 ± 5.3% (aerial time). BLA% for vertical and leg stiffness was 6.4 ± 4.9% and 7.6 ± 3.6%, respectively. While distance covered decreased across repetitions (P < 0.05), there was no significant interaction between sprint repetitions and leg side for any of the mechanical variables studied (all P > 0.05). Although inter-limb differences were observed for many running kinetics/kinematics and spring-mass characteristics during repeated treadmill sprints, the lack of interaction between sprint repetitions and leg side suggests that lower limbs fatigued at a similar rate.     

Using Response Surface Analysis to Interpret the Impact of Parent–Offspring Personality Similarity on Adolescent Externalizing Problems

Personality similarity between parent and offspring has been suggested to play an important role in offspring's development of externalizing problems. Nonetheless, much remains unknown regarding the nature of this association. This study aimed to investigate the effects of parent–offspring similarity at different levels of personality traits, comparing expectations based on evolutionary and goodness‐of‐fit perspectives. Two waves of data from the TRAILS study (N = 1587, 53% girls) were used to study parent–offspring similarity at different levels of personality traits at age 16 predicting externalizing problems at age 19. Polynomial regression analyses and Response Surface Analyses were used to disentangle effects of different levels and combinations of parents and offspring personality similarity. Although several facets of the offspring's personality had an impact on offspring's externalizing problems, few similarity effects were found. Therefore, there is little support for assumptions based on either an evolutionary or a goodness‐of‐fit perspective. Instead, our findings point in the direction that offspring personality, and at similar levels also parent personality might impact the development of externalizing problems during late adolescence. © 2017 The Authors. European Journal of Personality published by John Wiley & Sons Ltd on behalf of European Association of Personality Psychology     

Infinity in Ontology and Mind

Two fundamental categories of any ontology are the category of objects and the category of universals. We discuss the question whether either of these categories can be infinite or not. In the category of objects, the subcategory of physical objects is examined within the context of different cosmological theories regarding the different kinds of fundamental objects in the universe. Abstract objects are discussed in terms of sets and the intensional objects of conceptual realism. The category of universals is discussed in terms of the three major theories of universals: nominalism, realism, and conceptualism. The finitude of mind pertains only to conceptualism. We consider the question of whether or not this finitude precludes impredicative concept formation. An explication of potential infinity, especially as applied to concepts and expressions, is given. We also briefly discuss a logic of plural objects, or groups of single objects (individuals), which is based on Bertrand Russell’s (1903, The principles of mathematics, 2nd edn. (1938). Norton & Co, NY) notion of a class as many. The universal class as many does not exist in this logic if there are two or more single objects; but the issue is undecided if there is just one individual. We note that adding plural objects (groups) to an ontology with a countable infinity of individuals (single objects) does not generate an uncountable infinity of classes as many.

经典力学革命中的概念图式变化

经典力学革命中起核心作用的是运动概念的变化。亚里士多德力学把运动理解成位移,这种运动概念与因果解释图式一起,限定了力学解释的基本特征。为了解决抛体问题而引入的冲力理论是一个过渡,伽利略在用冲力理论解释自由落体运动时改变了思考问题的方向,转向新的运动概念——运动就是瞬时运动。这个概念结合力学解释的因果图式预告了惯性定律。     

QUANTUM MECHANICS,TIME, AND THEOLOGY: INDEFINITE CAUSAL ORDER AND A NEW APPROACH TO SALVATION

Quantum mechanics has recently indicated that, at the fundamental level, temporal order is not fixed. This phenomenon, termed Indefinite Causal Order, is yet to receive metaphysical or theological engagement. We examine Indefinite Causal Order, particularly as it emerges in a 2018 photonic experiment. In this experiment, two operations A and B were shown to be in a superposition with regard to their causal order. Essentially, time, intuitively understood as fixed, flowing, and fundamental, becomes fuzzy. We argue that if Indefinite Causal Order is true, this is good evidence in favor of a B-theory of time, though such a B-theory requires modification. We then turn to theology, suggesting that a B-theoretic temporal ontology invites serious reconsideration of the doctrine of salvation. This paper concludes that the best explanation for salvation given a B-theory is mind-dependent salvific becoming, a type of psychological soteriological change that occurs through downward causation.     

OVERVIEW OF THE STRUCTURE OF A SCIENTIFIC WORLDVIEW

Abstract. Understanding the structure of a scientific world view is important for the dialogue between science and religion. In this essay, I define comprehensive worldview and distinguish it from the more focused non comprehensive worldview. I explain that scientists and the public at large agree that modern research works in a scientific as opposed to nonscientific worldview. I give some of the essential elements of any scientific worldview that differentiate it from nonscientific ones. These elements are the general pre suppositions of science, the methods of science, and the articles of justification for the conclusions science puts forward. I question whether a scientific worldview can allow philosophical and theological tenets, which might appear to stand opposed to scientific paradigms, and conclude that the answer lies in the scope of its comprehensiveness.