ACUTE EFFECT OF VIBRATORY STIMULATION ON ELBOW JOINT FLEXOR PERFORMANCE

A novel design of vibratory stimulation training system which can provide precisely controlled smooth force profile to the participants is introduced. All participants received 4 treatments with 20s of vibratory stimulation at a specific frequency and amplitude. The experimental data were analyzed through the two-way repeated-measures ANOVA analysis, with the independent variables being vibratory frequency and amplitude, and the dependent variables EMGrms, Fmax, RFD0.5s, and Fave. An optimal vibratory stimulation pattern was found from this study that has the most significant acute effect on the elbow joint flexor muscle performance: a 60% maximal force loading combined with vibratory stimulation at a frequency of 2.5 Hz and amplitude of 1 N sustained over 20s

The Information-Leveling Role of Voluntary Disclosure Quality in Facilitating Investment Efficiency

This study examines whether and under what conditions voluntary disclosure quality plays an information-leveling role in facilitating investment efficiency. Measuring voluntary disclosure quality as the (inverse) standard deviation of managers’ prior earnings forecast errors (i.e., management forecast consistency), we document a positive association between management forecast consistency and investment efficiency that strengthens when the information environment becomes more constrained and when there are negative shocks to financial reporting quality. We also find that the management forecast consistency/investment efficiency association strengthens when firms are younger, faster growing, and financially constrained, but not when firms are weakly governed and financially unconstrained, which suggests that voluntary disclosure quality facilitates investment efficiency by mitigating adverse selection (but not moral hazard) frictions. Last, when we employ a changes-based model, we find that increases in management forecast consistency are associated with increases in investment efficiency, which mitigates concerns that voluntary disclosure quality’s empirical link to investment efficiency is purely driven by managers’ inherent forecasting abilities. Overall, we show that voluntary disclosure quality can facilitate investment efficiency when financial reporting and other elements of the information environment are constrained in their ability to mitigate market frictions that impede efficiency

Gallic Acid Induces a Reactive Oxygen Species-Provoked c-Jun NH 2

Idiopathic pulmonary fibrosis is a chronic lung disorder characterized by fibroblasts proliferation and extracellular matrix accumulation. Induction of fibroblast apoptosis therefore plays a crucial role in the resolution of this disease. Gallic acid (3,4,5-trihydroxybenzoic acid), a common botanic phenolic compound, has been reported to induce apoptosis in tumor cell lines and renal fibroblasts. The present study was undertaken to examine the role of mitogen-activated protein kinases (MAPKs) in lung fibroblasts apoptosis induced by gallic acid. We found that treatment with gallic acid resulted in activation of c-Jun NH2-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), and protein kinase B (PKB, Akt), but not p38MAPK, in mouse lung fibroblasts. Inhibition of JNK using pharmacologic inhibitor (SP600125) and genetic knockdown (JNK specific siRNA) significantly inhibited p53 accumulation, reduced PUMA and Fas expression, and abolished apoptosis induced by gallic acid. Moreover, treatment with antioxidants (vitamin C, N-acetyl cysteine, and catalase) effectively diminished gallic acid-induced hydrogen peroxide production, JNK and p53 activation, and cell death. These observations imply that gallic acid-mediated hydrogen peroxide formation acts as an initiator of JNK signaling pathways, leading to p53 activation and apoptosis in mouse lung fibroblasts

Rhodiola crenulata extract for prevention of acute mountain sickness: a randomized, double-blind, placebo-controlled, crossover trial

BACKGROUND: Rhodiola crenulata (R. crenulata) is widely used to prevent acute mountain sickness in the Himalayan areas and in Tibet, but no scientific studies have previously examined its effectiveness. We conducted a randomized, double-blind, placebo-controlled crossover study to investigate its efficacy in acute mountain sickness prevention. METHODS: Healthy adult volunteers were randomized to 2 treatment sequences, receiving either 800 mg R. crenulata extract or placebo daily for 7 days before ascent and 2 days during mountaineering, before crossing over to the alternate treatment after a 3-month wash-out period. Participants ascended rapidly from 250 m to 3421 m on two separate occasions: December 2010 and April 2011. The primary outcome measure was the incidence of acute mountain sickness, as defined by a Lake Louise score ≥ 3, with headache and at least one of the symptoms of nausea or vomiting, fatigue, dizziness, or difficulty sleeping. RESULTS: One hundred and two participants completed the trial. There were no demographic differences between individuals taking Rhodiola-placebo and those taking placebo-Rhodiola. No significant differences in the incidence of acute mountain sickness were found between R. crenulata extract and placebo groups (all 60.8%; adjusted odds ratio (AOR) = 1.02, 95% confidence interval (CI) = 0.69–1.52). The incidence of severe acute mountain sickness in Rhodiola extract vs. placebo groups was 35.3% vs. 29.4% (AOR = 1.42, 95% CI = 0.90–2.25). CONCLUSIONS: R. crenulata extract was not effective in reducing the incidence or severity of acute mountain sickness as compared to placebo. TRIAL REGISTRATION: ClinicalTrials.gov NCT01536288

Experimental procedures for precision measurements of the Casimir force with an Atomic Force Microscope

Experimental methods and procedures required for precision measurements of the Casimir force are presented. In particular, the best practices for obtaining stable cantilevers, calibration of the cantilever, correction of thermal and mechanical drift, measuring the contact separation, sphere radius and the roughness are discussed.Comment: 14 pages, 7 figure