The relationship between free-throw accuracy and performance variables in male wheelchair basketball players

We investigated the relationship between the free-throw accuracy and performance variables among fourteen elite male wheelchair basketball players. Participants performed 20 basketball free-throws. Basketball performance variables were the phases of the pre-shoot routine: (a) time taken, (b) minimum angle when taking the ball back, (c) angle at ball release, (d) angular displacement during the forward arm swing, and (e) angular velocity at ball release on the elbow, shoulder, and hip. A significant negative correlation was observed between the free-throw accuracy and mean pre-shot time, suggesting that participants with a shorter pre-shot time showed a higher free-throw accuracy. In addition, a significant negative correlation was found between the free-throw accuracy and variability of angular velocity of the hip at the time of ball release, indicating that the consistency of hip movement is an important factor in free-throw accuracy. In contrast, there were no relationship between the free-throw accuracy and player’s classification point defined as International Wheelchair Basketball Federation, and experience of wheelchair basketball. These data suggest that the routine duration and trunk movement are related to free-throw accuracy in wheelchair basketball

Dynamic cerebral autoregulation during cognitive task:Effect of hypoxia

Changes in cerebral blood flow (CBF) subsequent to alterations in the partial pressures of oxygen and carbon dioxide can modify dynamic cerebral autoregulation (CA). While cognitive activity increases CBF, the extent to which it impacts CA remains to be established. In the present study we determined whether dynamic CA would decrease during a cognitive task and whether hypoxia would further compound impairment. Fourteen young healthy subjects performed a simple Go/No-go task during normoxia and hypoxia (inspired O2 fraction = 12%), and the corresponding relationship between mean arterial pressure (MAP) and mean middle cerebral artery blood velocity (MCA Vmean) was examined. Dynamic CA and steady-state changes in MCA V in relation to changes in arterial pressure were evaluated with transfer function analysis. While MCA Vmean increased during the cognitive activity ( P &lt; 0.001), hypoxia did not cause any additional changes ( P = 0.804 vs. normoxia). Cognitive performance was also unaffected by hypoxia (reaction time, P = 0.712; error, P = 0.653). A decrease in the very low- and low-frequency phase shift (VLF and LF; P = 0.021 and P = 0.01) and an increase in LF gain were observed ( P = 0.037) during cognitive activity, implying impaired dynamic CA. While hypoxia also increased VLF gain ( P &lt; 0.001), it failed to cause any additional modifications in dynamic CA. Collectively, our findings suggest that dynamic CA is impaired during cognitive activity independent of altered systemic O2 availability, although we acknowledge the interpretive complications associated with additional competing, albeit undefined, inputs that could potentially distort the MAP-MCA Vmean relationship. NEW &amp; NOTEWORTHY During normoxia, cognitive activity while increasing cerebral perfusion was shown to attenuate dynamic cerebral autoregulation (CA) yet failed to alter reaction time, thereby questioning its functional significance. No further changes were observed during hypoxia, suggesting that impaired dynamic CA occurs independently of altered systemic O2 availability. However, impaired dynamic CA may reflect a technical artifact, given the confounding influence of additional inputs that could potentially distort the mean arterial pressure-mean middle cerebral artery blood velocity relationship. </jats:p

Heat Transportation by Acicular Micro-Textured Device with Semi-Regular Alignment

Heat transportation device was developed to improve the cooling capacity through the heat convection process and to make low-temperature radiation from the heat source to the objective body in vacuum. This device consisted of the metallic substrate and the acicular micro−/nano-textures in semi-regular alignment. The micro-cone unit cell size and pitch in these textures was controllable by tuning the total current and the current density in the electrochemical processing. Four devices with various unit cell sizes and pitches were prepared for geometric characterization by SEM (Scanning Electron Miscopy) and for spectroscopic analyses on the IR-emittance by FT-IR (Fourier Transform-InfraRed) spectroscopy. Heat radiation experiment was performed to describe the heat transportation in vacuum from the heat source at 323 K to the objective plate. The texture size effect on the low-temperature heat radiation was investigated to build up a physical model for this heat radiation device. Heat convection experiment was also performed to describe the cooling capacity of device under the forced air flow. The unit cell height effect on the cooling behavior was discussed to deduce the physical model for this heat convection device. These models were considered to be used in the computational fluid mechanics simulations

Compensatory Upregulation of Myelin Protein Zero-Like 2 Expression in Spermatogenic Cells in Cell Adhesion Molecule-1-Deficient Mice

The cell adhesion molecule-1 (Cadm1) is a member of the immunoglobulin superfamily. In the mouse testis, Cadm1 is expressed in the earlier spermatogenic cells up to early pachytene spermatocytes and also in elongated spermatids, but not in Sertoli cells. Cadm1-deficient mice have male infertility due to defective spermatogenesis, in which detachment of spermatids is prominent while spermatocytes appear intact. To elucidate the molecular mechanisms of the impaired spermatogenesis caused by Cadm1 deficiency, we performed DNA microarray analysis of global gene expression in the testis compared between Cadm1-deficient and wild-type mice. Out of the 25 genes upregulated in Cadm1-deficient mice, we took a special interest in myelin protein zero-like 2 (Mpzl2), another cell adhesion molecule of the immunoglobulin superfamily. The levels of Mpzl2 mRNA increased by 20-fold and those of Mpzl2 protein increased by 2-fold in the testis of Cadm1-deficient mice, as analyzed with quantitative PCR and western blotting, respectively. In situ hybridization and immunohistochemistry demonstrated that Mpzl2 mRNA and protein are localized in the earlier spermatogenic cells but not in elongated spermatids or Sertoli cells, in both wild-type and Cadm1-deficient mice. These results suggested that Mpzl2 can compensate for the deficiency of Cadm1 in the earlier spermatogenic cells

The relationship between pitching parameters and release points of different pitch types in major league baseball players

ObjectivesThe purpose of this study was to deepen our understanding of pitches and to obtain basic knowledge about pitches by comparing 4-seam and other pitches in Major League Baseball (MLB).MethodsWe analyzed big data for 1,820 professional baseball pitchers of MLB on release speed, spin rate, release point 3D coordinates (X, Y, and Z axes), amount of change for 4-seam, and seven changing ball types (sinker, slider, changeup, cutter, curve, split finger, and knuckle curve), using PITCHf/x and TrackMan. We also evaluated three relationships: (1) between the release points and the ball types of pitch; (2) between the amount of change in the ball and the release speed; and (3) between the release speed and the spin rate.ResultsThe release speed was significantly slower in seven changing ball types than in the 4-seam (p &lt; 0.01, respectively). The spin rate and the amount of change (ΔX and ΔZ) were significantly different between 4-seam and seven changing ball types (p &lt; 0.01, respectively). Release point 3D coordinates (X, Y, and Z axes) were significantly different between 4-seam and slider, cutter, and curve (p &lt; 0.01, respectively). Based on these findings, the eight pitch types were mainly divided into three groups: 4-seam, curve, and off-speed pitch types.ConclusionSeven changing ball types included specific characteristics for each parameter. The correspondence among the release speed, ΔX, and ΔZ at the 3D coordinates is an arch with 4-seam as the apex. Our results suggest an effective strategy for changing the release point and displacement of a ball's trajectory to improve the performance of baseball pitchers

Quantitative Analysis of the Cellular Composition in Seminiferous Tubules in Normal and Genetically Modified Infertile Mice

The aim of this study was to establish a quantitative standard for the cellular composition in seminiferous tubules at each stage of spermatogenesis in the mouse testis, and thereby evaluate abnormalities in the infertile mouse testis. We applied a combination of lectin histochemistry for acrosomes and immunohistochemistry for various specific cell markers, both of which were visualized with fluorescence, on paraffin sections of the testis. We first examined seminiferous tubules from normal mice and counted the number of each cell type at each stage of spermatogenesis. We then examined seminiferous tubules from genetically modified mice deficient (-/-) for one of the cell adhesion molecules, nectin-2 or nectin-3, and compared the number of each cell type at each stage of spermatogenesis with the corresponding value in normal mice. In both nectin-2-/- and nectin-3-/- mice, which are infertile despite the apparently normal morphology of the seminiferous epithelia, we measured a progressive loss in the later-step spermatids, with significantly lower numbers of step 11–16 spermatids in nectin-3-/- mice and step 15–16 spermatids in nectin-2-/- mice as compared with that in normal control mice. The present study demonstrated that a quantitative analysis of cellular compositions at different stages in seminiferous tubules was useful for evaluating abnormalities in spermatogenesis

Dual Microcatheter Retrograde Transvenous Obliteration of Gastric Varices: Coil Embolization as a Substitute for Balloon Occlusion

Dual microcatheter retrograde transvenous obliteration (DMRTO) of gastric varices enables dual microcatheters to be advanced to the gastric varices themselves or to a site adjacent to the varices. The sclerosing agent is infused through the first microcatheter following coil embolization of the outflow vessels through the second microcatheter, which is placed several centimeters back from the varices. We present two cases of gastric varices in whom balloon-occluded retrograde transvenous obliteration failed, because of angulated gastrosubphrenic shunt in case 1 and a tortuous and elongated gastrorenal shunt in case 2. DMRTO successfully achieved eradication of the gastric varices in both cases

Inhibition of p600 Expression Suppresses Both Invasiveness and Anoikis Resistance of Gastric Cancer

BACKGROUND: Advanced gastric cancers often metastasize to distant organs and the peritoneum, leading to a poor prognosis. Both invasiveness and resistance to anchorage-independent cell death (anoikis) are important factors in the process of metastasis. p600 (600-kDa protein), recently identified from a cervical cancer cell line, plays a role in both anoikis resistance and cell migration. In this study, we examined whether p600 is involved in the progression of gastric cancer. METHODS: We used both normal gastric mucosal cells and cancer cells laser-microdissected from 42 gastric cancers and their normal counterparts, and compared their p600 mRNA expression levels with quantitative reverse transcriptase–polymerase chain reaction. We inhibited p600 expression in two gastric cancer cell lines with siRNA and examined its effect on the invasiveness and anoikis resistance both in vitro and in vivo. RESULTS: Expression of p600 mRNA was significantly higher in gastric cancer cells than in normal mucosal cells (P = 0.027). The invasion assay revealed that invasiveness was significantly reduced by inhibition of p600 (P < 0.01). In vitro experiments revealed that cell viability and colony-formation capacity under anchorage-independent conditions were significantly reduced by inhibition of p600 (P < 0.05). In vivo experiments also showed that the establishment of intraperitoneal disseminated tumors was significantly suppressed by transient inhibition of p600 (P < 0.001). CONCLUSIONS: Our results strongly suggest that p600 is involved in gastric cancer progression, and has a potential to be a new molecular target for gastric cancer therapy

The Modulation of Corticospinal Excitability during Motor Imagery of Actions with Objects

We investigated whether corticospinal excitability during motor imagery of actions (the power or the pincer grip) with objects was influenced by actually touching objects (tactile input) and by the congruency of posture with the imagined action (proprioceptive input). Corticospinal excitability was assessed by monitoring motor evoked potentials (MEPs) in the first dorsal interosseous following transcranial magnetic stimulation over the motor cortex. MEPs were recorded during imagery of the power grip of a larger-sized ball (7 cm) or the pincer grip of a smaller-sized ball (3 cm)—with or without passively holding the larger-sized ball with the holding posture or the smaller-sized ball with the pinching posture. During imagery of the power grip, MEPs amplitude was increased only while the actual posture was the same as the imagined action (the holding posture). On the other hand, during imagery of the pincer grip while touching the ball, MEPs amplitude was enhanced in both postures. To examine the pure effect of touching (tactile input), we recorded MEPs during imagery of the power and pincer grip while touching various areas of an open palm with a flat foam pad. The MEPs amplitude was not affected by the palmer touching. These findings suggest that corticospinal excitability during imagery with an object is modulated by actually touching an object through the combination of tactile and proprioceptive inputs