This research aims to investigate the development of muscle fatigue and the recovery process revealed by tissue oxygenation. The tissue hemodynamics were measured by near-infrared spectroscopy (NIRS) ...during a 30-min pre-exercise rest, a 40-cycle heel-lift exercise and a 30-min post-exercise recovery. Wavelet transform was used to obtain the normalized wavelet energy in six frequency intervals (I–VI) and inverse wavelet transform was applied to extract exercise-induced oscillations from the hemodynamic signals. During the exercise phase, the contraction-related oscillations in the total hemoglobin signal (ΔtHb) showed a decreasing trend while the fluctuations in the tissue oxygenation index (TOI) displayed an increasing tendency. The mean TOI value was significantly higher (p < 0.001) under recovery (65.04% ± 2.90%) than that under rest (62.35% ± 3.05%). The normalized wavelet energy of the ΔtHb signal in frequency intervals I (p < 0.001), II (p < 0.05), III (p < 0.05) and IV (p < 0.01) significantly increased by 43.4%, 23.6%, 18.4% and 21.6% during the recovery than that during the pre-exercise rest, while the value in interval VI (p < 0.05) significantly decreased by 16.6%. It could be concluded that NIRS-derived hemodynamic signals can provide valuable information related to muscle fatigue and recovery.
Compression garments can enhance performance and promote recovery in athletes. Different body coverage with compression garments may impose distinct effects on kinematic movement mechanics and thus ...basketball free-throw accuracy. The objective of this study was to examine basketball free-throw shooting accuracy, consistency and the range of motion of body joints while wearing upper-, lower- and full-body compression garments. Twenty male basketball players performed five blocks of 20 basketball free-throw shooting trials in each of the following five compression garment conditions: control-pre, top, bottom, full (top + bottom) and control-post. All conditions were randomized except pre- and post-control (the first and last conditions). Range of motion of was acquired by multiple inertial measurement units. Free-throw accuracy and the coefficient of variation were also analyzed. Players wearing upper-body or full-body compression garments had significantly improved accuracy by 4.2% and 5.9%, respectively (p < 0.05), but this difference was not observed with shooting consistency. Smaller range of motion of head flexion and trunk lateral bending (p < 0.05) was found in the upper- and full-body conditions compared to the control-pre condition. These findings suggest that an improvement in shooting accuracy could be achieved by constraining the range of motion through the use of upper-body and full-body compression garments.
A synthesis of tellurium-embedded π-extended aromatics from tellurium powder and readily available cyclic diaryliodonium salts has been developed. The versatility of this method has been demonstrated ...by the synthesis of various functionalized dibenzotellurophenes (DBTe’s), a ladder-type π-system, and a heterosumanene. These compounds demonstrated good air/moisture stability and high thermal stability. Remarkably, many DBTe’s exhibited interesting tunable room-temperature phosphorescence (RTP) in the solid state.
An efficient, copper-catalyzed 3+1+1 cycloaddition reaction was developed for the expedient synthesis of pharmacologically interesting polysubstituted pyrroles from easily available nitrones and ...α-acidic isocyanides. The given approach features a new mode of cycloaddition between nitrones and isocyanides with wide substrate scope, good functional group tolerance, and operational simplicity. The operando infrared spectroscopy was used for the characterization of reaction intermediates.
An efficient palladium-catalyzed oxidative annulation reaction was developed through sequential isocyanide insertions into N–H and O–H bonds of hydrazides, which provides an efficient access to ...valuable 2-amino-1,3,4-oxadiazoles and their derivatives.
Unsupervised sentence embedding learning is a fundamental task in natural language processing. Recently, unsupervised contrastive learning based on pre-trained language models has shown impressive ...performance in sentence embedding learning. This method aims to align positive sentence pairs while pushing apart negative sentence pairs to achieve semantic uniformity in the representation space. However, most previous literature leverages a random strategy to sample negative pairs, which suffers from the risk of selecting uninformative negative examples (e.g., easily distinguishable examples, anisotropic representations), thus greatly affecting the quality of learned representations. To address this issue, we propose
nmCSE
, a negative mining contrastive learning method for sentence embedding. Specifically, we introduce distance moderation and spatial uniformity as two properties of informative negative examples, and devise distance-based weighting and grid sampling as two strategies to preserve these properties, respectively. Our proposal outperforms the random strategy across seven semantic textual similarity datasets. Furthermore, our method can easily be adapted to other contrastive learning scenarios (e.g., vision), and does not introduce significant computational overhead.
An efficient rhodium-catalyzed regioselective C–H bond cyanation of arenes was developed using tert-butyl isocyanide as the cyanide source. A wide range of (hetero)aryl and cycloalkenyl nitriles ...could be afforded with high regioselectivity and good functional group tolerance.
An efficient rhodium-catalyzed regioselective C–N bond formation of azo compounds in good to excellent yields through C–H bond functionalization using azides as the nitrogen source was developed. ...Alkyl, aryl, and sulfonyl azides could be efficiently assembled in this reaction with excellent functional group tolerance.
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