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.     

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。     

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.

Non-monotonic Probability Theory and Photon Polarization

A non-monotonic theory of probability is put forward and shown to have applicability in the quantum domain. It is obtained simply by replacing Kolmogorov’s positivity axiom, which places the lower bound for probabilities at zero, with an axiom that reduces that lower bound to minus one. Kolmogorov’s theory of probability is monotonic, meaning that the probability of A is less then or equal to that of B whenever A entails B. The new theory violates monotonicity, as its name suggests; yet, many standard theorems are also theorems of the new theory since Kolmogorov’s other axioms are retained. What is of particular interest is that the new theory can accommodate quantum phenomena (photon polarization experiments) while preserving Boolean operations, unlike Kolmogorov’s theory. Although non-standard notions of probability have been discussed extensively in the physics literature, they have received very little attention in the philosophical literature. One likely explanation for that difference is that their applicability is typically demonstrated in esoteric settings that involve technical complications. That barrier is effectively removed for non-monotonic probability theory by providing it with a homely setting in the quantum domain. Although the initial steps taken in this paper are quite substantial, there is much else to be done, such as demonstrating the applicability of non-monotonic probability theory to other quantum systems and elaborating the interpretive framework that is provisionally put forward here. Such matters will be developed in other works.     

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.     

QUANTUM AND CONSCIOUSNESS: IN SEARCH OF A NEW PARADIGM

Abstract. Two fundamental issues raised by Lothar Schäfer are considered: (1) the question of a suitable paradigm within which the findings of quantum physics can be optimally interpreted and (2) the question of the assessment of the presence and importance of mind and consciousness in the universe. In regard to the former, I contend that the ideal of science is to interpret its findings in an optimally consistent and minimally speculative framework. In this context Schäfer's assertion that certain findings in quantum physics (those that relate to virtual states) indicate the presence of mind at the quantum level implies a dualistic and hence unnecessarily speculative assumption. In regard to the assessment of mind and consciousness, a consistent and parsimonious paradigm suggests that mind and consciousness are not part of a chain of events consisting of an admixture of physical and mental events but that physical events form a single, coherent set of events, and mental events another set, with the two sets related, as Teilhard (and a number of other philosophers, including White head) affirmed, as the “within” and the “without” (or the “mental pole” and the “physical pole”) of one and the same fundamental reality. This panpsychist as contrasted with Schäfer's dualist paradigm provides a single self‐consistent framework for the interpretation of quantum (and all natural) events while recognizing the presence of mind in the universe as the least speculative realist implication of our immediate experience of consciousness.     

A RESPONSE TO ERVIN LASZLO: QUANTUM AND CONSCIOUSNESS

Abstract. I respond to Ervin Laszlo's suggestions and criticism regarding my essay in this issue of Zygon. Virtual atomic orbitals are used as a model to illustrate the existence of a general realm of potentiality in physical reality from which the actual world emanates. Laszlo's suggestions for “paradigm repair” are supported and accepted as essentially being in agreement with my intentions and as offering highly useful clarifications. I compare virtual states to historic ideas of forms as metaphysical principles of being that inspire thoughts regarding the actions of a Cosmic Consciousness in the processes of the universe. Metaphysical and theological interpretations of the results of scientific research are defended, provided that they are not used to interfere a priori with the technical program of scientific research.     

SCIENCE'S CONCEPTION OF HUMAN BEINGS AS A BASIS FOR MORAL THEORY

Abstract. Niels Bohr stated, and Werner Heisenberg reiterated, that “in the great drama of existence we ourselves are both actors and spectators.” Their emphasis stems from the fact that the entry of human beings into physics as actors constitutes the most fundamental philosophical departure of twentieth‐century basic physics from its eighteenth‐ and nineteenth‐century forerunners. Those earlier theories claimed that our human conscious thoughts are mere witnesses to, or by‐products of, essentially mechanically determined brain processes. In stark contrast, certain conscious decisions that are made by human beings, but that are not determined by any known law, statistical or otherwise, enter irreducibly into orthodox contemporary physical theory. These actions are required to counteract effects of Heisenberg's Uncertainty Principle, which ordains that the physically described process of nature, acting alone, produces not a physical world of the kind we experience but rather a continuous smear of potential possible worlds of the kind we know. This contradiction between theory and experience is resolved in orthodox contemporary physical theory by bringing certain effects of our conscious human choices into the dynamics in essentially the way that we intuitively feel that our conscious intentions affect the physical world, namely, via the effects of our intentional efforts on our physically described bodies. The moral implications of this profound change in physics are discussed.     

意识新论

重新思考审视意识的特性：（1）意识是生命的重要组成。（2）在经典物理学领域,意识是生命的独特功能。在量子物理学领域,意识是宇宙万物的特性,以规则、意义和规律来表达。（3）意识包含精神与物质两种性状,但同时也是非物质非精神的。（4）意识可以穿越不同的时空。（5）意识能够产生能量。（6）意识可以分成四大类。（7）不同机体的意识可以相互交流。（8）意识可以遗传。（9）意识永恒存在。（10）意识可以因各种原因被重叠、掩盖或者忘记（意识非记忆）,但是在一定情况下,可以重新被发掘出来。