Realism in energy transition processes: an example from Bohmian quantum mechanics

In this paper we study in details a system of two weakly coupled harmonic oscillators from the point of view of Bohm’s interpretation of quantum mechanics. This system may be viewed as a simple model for the interaction between a photon and a photodetector. We obtain exact solutions for the general case. We then compute approximate solutions for the case where one oscillator is initially in its first excited state (a single photon) reaching the other oscillator in its ground state (the photodetector). The approximate solutions represent the state of both oscillators after the interaction, which is not an eigenstate of the individual hamiltonians for each oscillator, and therefore the energies for each oscillator do not exist in the Copenhagen interpretation of Quantum Mechanics. We use the approximate solutions that we obtained to compute Bohmian trajectories and to study the energy transfer between the oscillators. We conclude that, even using the Bohmian view, the energy of each individual oscillator is not well defined, as the nonlocal quantum potential is not negligible even after the coupling is turned off.     

High temperature mechanics of nanomoulded amorphous metals

High temperature mechanics of nanomoulded amorphous metals was investigated by in situ nanomechanical testing. Nanopillars of Pd₄₃Cu₂₇Ni₁₀P₂₀ metallic glass were synthesized by thermoplastic forming and their stress–strain response was obtained concurrent with direct observation of their deformation behaviour. This allowed the measurement of mechanical behaviour from nanopillars and the corresponding bulk substrate with identical thermal history. A rise in elastic modulus was seen with increase in temperature for both the nanopillars and substrate, which was explained by diffusive rearrangement of atomic-scale viscoelastic units. The results provide fundamental insights into structural rearrangement in metallic glasses.     

Semiclassical Theism and the Passage of Planck Times

This paper models God and time in the framework of modern physics. God bridges and simultaneously exists in (1) a universe with infinite tenseless time and (2) a created parallel universe with tensed time and a point origin. The primary attributes of God are inexhaustible love, inexhaustible perception, and inexhaustible force. The model also incorporates modern physics theories that include relativity, the conservation of energy, quantum mechanics, and multiverse geometry. For example, creation out of nothing and divine intervention are subject to physical processes and likewise nomological possibility. I will call this model semiclassical theism.     

Elastic solutions with arbitrary elastic inhomogeneity and anisotropy

An efficient numerical algorithm is proposed to accurately compute the elastic fields in two-dimensional (2D) or three-dimensional (3D) microstructures with arbitrary elastic inhomogeneity and anisotropy. It combines the equivalent inclusion method of Eshelby, the microelasticity theory of Khachaturyan, and the spectral iterative perturbation method of Hu and Chen. Its efficiency is compared with those of existing approaches in the literature. The method can be conveniently implemented in phase-field modeling of stress-dependent microstructure evolution and/or of mass/electrical transport.     

An analytic solution of initial boundary value problem for 3D quasicrystals in half space

In this article, initial boundary value problem for 3D quasicrystals in half space is considered. An analytic method is proposed for special form of initial conditions and nonhomogeneous term. It is explained that a weak solution of the problem can be constructed in the similar form of data by using symbolic calculations.     

关于大学生心理障碍干预模式的理论建构

本文在已有研究的基础上,根据大学生心理发展与心理素质的特点和不同心理学派的理论观点建构了大学生心理障碍干预模式,该模式由多维系统的干预途径、多样渗透的干预方法、丰富全面的干预工作内容和完善化人性化的干预机制组成,它们之间的关系既是独立的,又是相互协调和影响的。体现了大学生心理障碍干预模式的系统完整性及实施干预的灵活多样性和明确针对性。     

Ankle dorsiflexion range of motion is associated with kinematic but not kinetic variables related to bilateral drop-landing performance at various drop heights

Limited evidence is available concerning ankle dorsiflexion range of motion (DF ROM) and its relationship with landing performance from varying drop heights. The aim of this investigation was to determine the relationship between ankle DF ROM and both kinetic and kinematic variables measured during bilateral drop-landings from 50%, 100% and 150% of countermovement jump height. Thirty-nine participants were measured for their ankle DF ROM using the weight-bearing lunge test, after which five bilateral drop-landings were performed from 50%, 100% and 150% of maximal countermovement jump height. Normalized peak vertical ground reaction force (vGRF), time to peak vGRF and loading rate was calculated for analysis, alongside sagittal-plane initial contact angles, peak angles and joint displacement for the hip, knee and ankle. Frontal-plane projection angles were also calculated. Ankle DF ROM was not related to normalized peak vGRF, time to peak vGRF or loading rate (P > 0.05), regardless of the drop height. However, at drop heights of 100% and 150% of countermovement jump height, there were numerous significant (P < 0.05) moderate to large correlations between ankle DF ROM and initial contact angles (r = −0.34 to −0.40) and peak angles (r = −0.42 to −0.52) for the knee and ankle joint. Knee joint displacement (r = 0.39–0.47) and frontal-plane projection angle (r = 0.37–0.40) had a positive relationship with ankle DF ROM, which was consistent across all drop heights. Ankle DF ROM influences coordination strategies that allow for the management of vGRF during bilateral drop-landings, with alterations in alignment for the knee and ankle joints at both initial contact and peak angles.     

The effects of instructional cues on performance and mechanics during a gross motor movement

Externally focused instructions specific to performance have shown to improve body mechanics (Gokeler et al., 2015; Welling, Benjaminse, Gokeler, & Otten, 2016). However, the effect of using an external focus instruction may have been more profound if the content of the instruction had been relevant to mechanics. Therefore, the present study examined the effects of externally focused instructions specific to performance and externally focused instructions specific to body mechanics on mechanics and performance. Twenty-four adults (n = 12 males; n = 12 females) performed a series of drop jumps following external focus cues that were specific to performance and landing mechanics. Participants completed a drop jump followed by a maximal effort vertical jump. The initial contact, maximal angle, and range of motion at the knee in the sagittal and frontal plane motion were measured for mechanics and the height of the second vertical jump was measured for performance. The results suggest external focus instructions specific to performance are beneficial for performance, but not for improving landing mechanics. This suggests that external focus instructions must be specific to the contents of the instruction.     

Stability of pace and turn parameters of elite long-distance swimmers

This study aimed to assess the stability of the performance, pace and turn parameters of elite long-distance male swimmers during an 800 m freestyle race. The sample was composed by 38 male swimmers, participating in the 800 m event at the 2016 LEN European Aquatic Championships (long course meter). The performance, and a set of pace and turn parameters were analyzed. A customized software was used to perform each race analysis. Swimmers spent 64.05 ± 0.50% and 35.95 ± 0.49% of the final race time in the clean swim and turns, respectively. In the pace parameters, the clean swim was the only one that did not differ between the first and second half of the race (1.63 ± 0.05 vs 1.62 ± 0.05 m·s⁻¹), and in the turn parameters, the water break distance was also similar (5.13 ± 1.17 vs 5.06 ± 0.98 m). A significant and moderate-strong variation was verified for the performance (total race lap effect: p < 0.001, η² = 0.62), and a significant and moderate variation for the pace parameters (total race: p < 0.001, 0.15 ≤ η² ≤ 0.33), and for the turn parameters (total race: p < 0.01, 0.15 ≤ η² ≤ 0.33). Present data (pace and turn variation) shows that elite long-distance male swimmers do not maintain a similar pattern during an 800 m freestyle race. Future research is need to understand if this lack of pace and turn stability is the best way to enhance the performance, or if swimmers should be advised to control their pace and turn. Nevertheless, coaches are advised to help swimmers with feedback about their pace (i.e., controlling the intermediate 30 m) and turn performances (i.e., controlling the 5 m in and 15 m out), leading to a positive effect in their final race time.