Miracle-dz/UniFAR-FTUs huggingface dataset:
The Effect of Crank Resistance on Arm Configuration and Muscle Activation Variances in Arm Cycling Movements

Abstract Arm cycling on an ergometer is common in sports training and rehabilitation protocols. The hand movement is constrained along a circular path, and the user is working against a resistance, maintaining a cadence. Even if the desired hand trajectory is given, there is the flexibility to choose patterns of joint coordination and muscle activation, given the kinematic redundancy of the upper limb. With changing external load, motor noise and changing joint stiffness may affect the pose of the arm even though the endpoint trajectory is unchanged. The objective of this study was to examine how the crank resistance influences the variances of joint configuration and muscle activation. Fifteen healthy participants performed arm cranking on an arm-cycle ergometer both unimanually and bimanually with a cadence of 60 rpm against three crank resistances. Joint configuration was represented in a 3-dimensional joint space defined by inter-segmental joint angles, while muscle activation in a 4-dimensional "muscle activation space" defined by EMGs of 4 arm muscles. Joint configuration variance in the course of arm cranking was not affected by crank resistance, whereas muscle activation variance was proportional to the square of muscle activation. The shape of the variance time profiles for both joint configuration and muscle activation was not affected by crank resistance. Contrary to the prevailing assumption that an increased motor noise would affect the variance of auxiliary movements, the influence of noise doesn’t appear at the joint configuration level even when the system is redundant. Our results suggest the separation of kinematic- and force-control, via mechanisms that are compensating for dynamic nonlinearities. Arm cranking may be suitable when the aim is to perform training under different load conditions, preserving stable and secure control of joint movements and muscle activations.
Synergistic Activation Patterns of Hand Muscles in Left-and Right-Hand Dominant Individuals

Abstract Handedness has been associated with behavioral asymmetries between limbs that suggest specialized function of dominant and non-dominant hand. Whether patterns of muscle co-activation, representing muscle synergies, also differ between the limbs remains an open question. Previous investigations of proximal upper limb muscle synergies have reported little evidence of limb asymmetry; however, whether the same is true of the distal upper limb and hand remains unknown. This study compared forearm and hand muscle synergies between the dominant and non-dominant limb of left-handed and right-handed participants. Participants formed their hands into the postures of the American Sign Language (ASL) alphabet, while EMG was recorded from hand and forearm muscles. Muscle synergies were extracted for each limb individually by applying non-negative-matrix-factorization (NMF). Extracted synergies were compared between limbs for each individual, and between individuals to assess within and across participant differences. Results indicate no difference between the limbs for individuals, but differences in limb synergies at the population level. Left limb synergies were found to be more similar than right limb synergies across left- and right-handed individuals. Synergies of the left hand of left dominant individuals were found to have greater population level similarity than the other limbs tested. Results are interpreted with respect to known differences in the neuroanatomy and neurophysiology of proximal and distal upper limb motor control. Implications for skill training in sports requiring dexterous control of the hand are discussed.
Acute and Delayed Effects of Fatigue on Ground Reaction Force, Lower Limb Stiffness and Coordination Asymmetries During a Landing Task

Abstract Landing is a critical phase of movement for injury occurrence, in which lower limbs should be used equally to better absorb the shock. However, it has been suggested that fatigue can lead to the appearance of asymmetries. The aim of this study was to verify the acute and delayed effects of fatigue on the lower limb asymmetry indexes of peak ground reaction force, leg stiffness and intra-limb coordination during a landing task. Fifteen physically active men performed a fatigue protocol composed of 14 sets of 10 continuous vertical jumps, with a one-minute rest interval between the sets. A step-off landing task was performed before, immediately after, 24 h and 48 h after the fatigue protocol. Two force plates and a video analysis system were used. The symmetry index equation provided the asymmetry indexes. For statistical analysis, ANOVA and effect size analysis were utilized. Inferential statistics did not show the effect of fatigue in the asymmetry indexes for any variable or condition (p > .05). Moderate effect sizes were observed for peak ground reaction force (0.61) and leg stiffness (0.61) immediately after the application of the protocol. In conclusion, fatigue does not seem to significantly change the asymmetries of lower limbs, especially regarding intra-limb coordination. The moderate effects observed for peak ground reaction force and leg stiffness asymmetries suggest that these variables may be acutely affected by fatigue.
Determination of germanium ionization coefficients from small signal IMPATT diode characteristics

Small-signal measurements of germanium IMPATT diode admittance in the frequency range from 2 to 8 GHz were taken for various current densities. These measurements were compared with the small-signal admittances calculated using the model developed by Gummel, Scharfetter, and Blue [1], [2]. Values for the ionization coefficients and saturated velocities for electrons and holes used for the calculations have been chosen to secure reasonable agreement between theory and experiment for the diode avalanche voltage, the frequencies at which the small-signal susceptance and conductance cross zero, and the slope and general shape of the admittance versus frequency curves. The calculated small-signal admittance characteristics of the n+-p-p+mesa diode investigated are quite sensitive to the saturated hole velocity and the field dependence of the ionization rates. For the operating junction temperature, the velocity which gives the best fit is resolvable to about 5 percent. The best fit velocity is in agreement with published values. However, the ionization coefficients determined give a substantially smaller dependence of ionization rate on electric field than was obtained by Miller [3]. The coefficients obtained can be fitted by Baraff's theoretical model [4] using a low value for r, the normalized ionization cross section, in order to obtain the small dependence on field. The values of the ionization rates determined here, \alpha_{p}=2.15 \times 10_{5} \exp ( -7.10 \times 10_{5} V.cm-1/E) cm-1 \alpha_{n}=4.90 \times 10_{5} \exp ( -7.90 \times 10_{5} V.cm-1/E) cm-1are believed to be generally applicable to impact ionization effects in germanium semiconductor devices.
Weather, wheat, and war: Security implications of climate variability for conflict in Syria

We examine how Syria’s local growing seasons and precipitation variability affected patterns of violence during the country’s civil war (2011–19). Among Syria’s 272 subdistricts (nahiyah), we study conflict events initiated by the Assad regime or its allies, and, separately, by other armed non-government groups (‘rebels’). Throughout the war, violence to capture agriculture has been used regularly to control valuable cropland and harvests. Combatants also seek to deny their adversaries access to these resources by deploying violence to destroy agriculture. We test the hypothesis that conflict was most likely during local growing seasons due to both of these motivations. Additionally, we examine whether unusually dry conditions further elevated the risk of conflict during growing season months. A theory for why higher levels of conflict would occur during unusually dry conditions is that livelihood losses elevate incentives to control scarce crops and also facilitate recruitment of militants or their sympathizers. We find that violent events initiated by the government and rebel groups are both more likely during the growing season than other times of the year. There is also evidence that dry conditions during the growing season led to an increase in government-initiated attacks over the duration of the war. We find the strongest relationship between precipitation deficits and both government- and rebel-initiated violence in later years of the war. Compared with our growing season results, the rainfall deviation estimates are less consistent across models.
The association between sustainability disclosures and the financial performance of Jordanian firms

Abstract Researchers are paying an unprecedented level of attention to the role that sustainability disclosures may play in enhancing financial performance. This study, therefore, examines this issue in a developing country context such as Jordan using a panel data set of 1,705 firm-year observations of firms listed on the Amman Stock Exchange. Fixed effect regression with robust standard errors is used to analyse the data. The results show that, while social and governance disclosures are positively associated with financial performance, environmental disclosures do not have this association. Interestingly, when sustainability disclosures are analysed collectively, a highly positive and significant association is found between them. This study recommends that the dimensions of sustainability disclosures complement each other to enhance firms’ financial performance.
Arthrospira platensis (Cyanobacteria) – a potential biofactory for fluoromagnetic nanoiron production

ABSTRACT Bioconversion of Fe3+ to Fe0 followed by spindle shaped magneto-fluorescent nanoiron production has been investigated using Arthrospira platensis as a potential bio-reagent. The characteristic features, e.g. in situ localisation, magnetic and fluorescent properties of synthesised nanoparticles, were explored. Bioconversion occurred when healthy growing biomass of Arthrospira platensis was exposed to 0.01 M aqueous solution of FeCl3 for 96 h at 25 °C with pH5.2. Spindle-shaped nanoiron was synthesised both inside and outside the cells. The average dry and hydrodynamic sizes for intracellular particles were 24.26 ± 3.40 nm × 5.45 ± 1.66 nm and 175.9 nm, respectively; whereas size variation for extracellular particles was 23.62 ± 3.49 nm × 8.41 ± 4.33 nm and 40.02 nm, respectively, as observed using transmission electron microscopy (TEM) and dynamic light scattering (DLS) analysis, respectively. Further characterisations were conducted using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, energy dispersive X-Ray spectroscopy (EDX), and X-Ray diffraction analysis (XRD). Nonspherical nanoiron particles generated multiple absorption bands at approximately 230, 350, and 480 nm in the UV-Vis spectra. Fluorescence of nanoiron was detected using confocal microscopy both inside and outside cells employing a blue filter (λex–425 nm, λem–475 nm). The magneto-fluorescent nature of synthesised nanoiron was estimated using fluorimetric analysis and dynamic light scattering study using a 0.5-tesla static magnetic field (SMF) at 4 °C. The investigation showed that the static magnetic field induced non-invasive clustering effect of nanoiron directly influence fluorescence intensity and its lifetime. The presence of superparamagnetism was detected in iron nanoparticles using a superconducting quantum interference device-vibrating sample magnetometer (SQUID-VSM).
Aspecific and specific intermolecular interactions in aqueous media

Aspecific as well as specific interactions involve the same noncovalent forces, consisting of Lifshitz‐van der Waals, Lewis acid/base, electrostatic, and thermal or Brownian movement interactions. In vivo, aspecific interactions between, e.g., cells and/or biopolymers usually are repulsive, while specific interactions are always attractive. The differences between the two classes of interactions can be shown to lie in the fact that aspecifically interacting bodies are large, while specifically interacting sites are small, or have a small radius of curvature, and in the fact that aspecifically interacting surfaces are homogeneous, whereas specific sites have a heterogeneous composition.
A Mobile NMR Sensor and Relaxometric Method to Non-destructively Monitor Water and Dry Matter Content in Plants

Water content (WC) and dry matter content (DMC) are some of the most basic parameters to describe plant growth and yield, but are exceptionally difficult to measure non-invasively. Nuclear Magnetic Resonance (NMR) relaxometry may fill this methodological gap. It allows non-invasive detection of protons in liquids and solids, and on the basis of these measures, can be used to quantify liquid and dry matter contents of seeds and plants. Unfortunately, most existing NMR relaxometers are large, unwieldy and not suitable to measure intact plants or to be used under field conditions. In addition, currently the appropriate NMR relaxometric methods are poorly suited for non-expert use. We here present a novel approach to overcome these drawbacks. We demonstrate that a basic NMR relaxometer with the capability to accept intact plants, in combination with straightforward NMR and data processing methods, can be used as an NMR plant sensor to continuously, quantitatively and non-invasively monitor changes in WC and DMC. This can be done in vivo, in situ, and with high temporal resolution. The method is validated by showing that measured liquid and solid proton densities accurately reflect WC and DMC of reference samples. The NMR plant sensor is demonstrated in an experimental context by monitoring WC of rice leaves under osmotic stress, and by measuring the dynamics of water and dry matter accumulation during seed filling in a developing wheat ear. It is further demonstrated how the method can be used to estimate leaf water potential on the basis of changes in leaf water content.
Metagenomics Reveals That Intravenous Injection of Beta-Hydroxybutyric Acid (BHBA) Disturbs the Nasopharynx Microflora and Increases the Risk of Respiratory Diseases

It is widely accepted that maintenance of microbial diversity is essential for the health of the respiratory tract; however, there are limited reports on the correlation between starvation and respiratory tract microbial diversity. In the present study, saline/β-hydroxybutyric acid (BHBA) intravenous injection after dietary restriction was used to imitate different degrees of starvation. A total of 13 healthy male yaks were imposed to different dietary restrictions and intravenous injections, and their nasopharyngeal microbiota profiles were obtained by metagenomic shotgun sequencing. In healthy yaks, the main dominant phyla were Proteobacteria (33.0%), Firmicutes (22.6%), Bacteroidetes (17.2%), and Actinobacteria (13.2%); the most dominated species was Clostridium botulinum (10.8%). It was found that 9 days of dietary restriction and 2 days of BHBA injection (imitating severe starvation) significantly decreased the microbial diversity and disturbed its structure and functional composition, which increased the risk of respiratory diseases. This study also implied that oral bacteria played an important role in maintaining nasopharynx microbial homeostasis. In this study, the correlation between starvation and nasopharynx microbial diversity and its potential mechanism was investigated for the first time, providing new ideas for the prevention of respiratory diseases.
Associations Between Maternal Thyroid Function and Birth Outcomes in Chinese Mother-Child Dyads: A Retrospective Cohort Study

Objective Although research suggests a close association between maternal thyroid function and birth outcomes, no clear conclusion has been reached. We aimed to explore this potential association in a retrospective cohort study. Methods This study included 8985 mother–child dyads. The maternal serum free tetraiodothyronine (FT4), thyroid-stimulating hormone (TSH), and thyroid peroxidase antibody (TPO Ab) concentrations and birth outcome data were reviewed from medical records. Subjects with TPO Ab concentrations of >34 and ≤34 IU/ml were classified into the TPO Ab positivity (+) and TPO Ab negativity (−) groups, respectively. Results Compared with subjects in the normal group (0.1 ≤ TSH < 2.5 mIU/L and TPO Ab−), those with TSH concentrations of 2.5–4.0 mIU/L and TPO Ab− had a 0.65-fold lower risk of low birth weight (LBW). In contrast, those with TSH concentrations of >4.0 mIU/L, regardless of the TPO Ab status, had a 2.01-fold increased risk of LBW. Subclinical hypothyroidism, regardless of the TPO Ab status, was associated with a 1.94-fold higher risk of LBW when compared with that in subjects with euthyroidism and TPO Ab−. No other significant associations were observed. Conclusion A maternal TSH concentration of 2.5–4.0 mIU/L was associated with a lower risk of LBW when combined with TPO Ab−, whereas subjects with a TSH concentration of >4.0 mIU/L had an increased risk of LBW. Subclinical hypothyroidism appears to be associated with a higher risk of LBW.
Heart Rate Dynamics During Acute Recovery From Maximal Aerobic Exercise in Young Adults

Introduction Resting heart rate (HRrest), heart rate variability (HRV), and HR recovery (HRR) from exercise provide valuable information about cardiac autonomic control. RR-intervals during acute recovery from exercise (RRrec) are commonly excluded from HRV analyses due to issues of non-stationarity. However, the variability and complexity within these trends may provide valuable information about changes in HR dynamics. Purpose Assess the complexity of RRrec and determine what physiologic and demographic information are associated with differences in these indices in young adults. Methods RR-intervals were collected throughout maximal treadmill exercise and recovery in young adults (n = 92). The first 5 min of RRrec were (1) analyzed with previously reported methods that use 3-interval lengths for comparison and (2) detrended using both differencing(diff) and polynomial regression(res). The standard deviation of the normal interval (SDNN), root mean square of successive differences (rMSSD), root mean square (RMS) of the residual of regression, and sample entropy (SampEn) were calculated. Repeated measures analysis of covariance (ANCOVA) tested for differences in these indices for each of the methodological approaches, controlling for race, body fat, peak oxygen uptake (VO2peak), and resting HR (HRrest). Statistical significance was set at p < 0.05. Results VO2peak and HRrest were significantly correlated with traditional measures of HRR and the variability surrounding RRrec. SampEndiff and SampEnres were correlated with VO2peak but not HRrest or HRR. The residual-method provided a significantly (p = 0.04) lower mean standard error (MSE) (0.064 ± 0.042) compared to the differencing-method (0.100 ± 0.033). Conclusions Complexity analysis of RRrec provides unique information about cardiac autonomic regulation immediately following the cessation of exercise when compared to traditional measures of HRR and both HRrest and VO2peak influence these results.
Editorial: Neurobiological Systems Underlying Reward and Emotions in Social Settings

1 Institute of Medical Psychology, Heidelberg University Hospital, Heidelberg, Germany, 2 Ruprecht-Karls University Heidelberg, Heidelberg, Germany, Department of Psychology, School of Social Sciences, University of Mannheim, Mannheim, Germany, 4 Research Group Biological Psychology, Department of Clinical Psychology, Central Institute of Mental Health, Heidelberg University/Medical Faculty Mannheim, Mannheim, Germany, Department of Psychology, Heidelberg University, Heidelberg, Germany, Bernstein Center for Computational Neuroscience Heidelberg/Mannheim, Mannheim, Germany, Department of Neuroscience and Biomedical Engineering, Aalto University, Espoo, Finland, 8 Interdisciplinary
Synthesis, characterizations, and mechanical properties of structurally modified poly(vinyl alcohol)

Poly(vinyl alcohol) (PVA) was structurally modified with two different types of chemicals under nitrogen atmosphere in the presence of Sb2O3 as a catalyst at 80°C in an aqueous medium. An FTIR and NMR spectrum confirmed the structural modification of PVA. DSC and TGA counseled the thermal properties of structurally modified PVA. Urea modified PVA exhibited higher mechanical strength than the pristine PVA. The FTIR-relative intensities of olefin formation and ketone formation were increased with the increase of weight of water. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Activation of Prefrontal Cortex in Process of Oral and Finger Shape Discrimination: fNIRS Study

Background The differences in the brain activities of the insular and the visual association cortices have been reported between oral and manual stereognosis. However, these results were not conclusive because of the inherent differences in the task performance-related motor sequence conditions. We hypothesized that the involvement of the prefrontal cortex may be different between finger and oral shape discrimination. This study was conducted to clarify temporal changes in prefrontal activities occurring in the processes of oral and finger tactual shape discrimination using prefrontal functional near-infrared spectroscopy (fNIRS). Methods Six healthy right-handed males [aged 30.8 ± 8.2 years (mean ± SD)] were enrolled. Measurements of prefrontal activities were performed using a 22-channel fNIRS device (ETG-100, Hitachi Medical Co., Chiba, Japan) during experimental blocks that included resting state (REST), nonsense shape discrimination (SHAM), and shape discrimination (SHAPE). Results No significant difference was presented with regard to the number of correct answers during trials between oral and finger SHAPE discrimination. Additionally, a statistical difference for the prefrontal fNIRS activity between oral and finger shape discrimination was noted in CH 1. Finger SHAPE, as compared with SHAM, presented a temporally shifting onset and burst in the prefrontal activities from the frontopolar area (FPA) to the orbitofrontal cortex (OFC). In contrast, oral SHAPE as compared with SHAM was shown to be temporally overlapped in the onset and burst of the prefrontal activities in the dorsolateral prefrontal cortex (DLPFC)/FPA/OFC. Conclusion The prefrontal activities temporally shifting from the FPA to the OFC during SHAPE as compared with SHAM may suggest the segregated serial prefrontal processing from the manipulation of a target image to the decision making during the process of finger shape discrimination. In contrast, the temporally overlapped prefrontal activities of the DLPFC/FPA/OFC in the oral SHAPE block may suggest the parallel procession of the repetitive involvement of generation, manipulation, and decision making in order to form a reliable representation of target objects.