Aharonov-Bohm Radiation of Fermions

We analyze Aharonov-Bohm radiation of charged fermions from oscillating solenoids and cosmic strings. We find that the angular pattern of the radiation has features that differ significantly from that for bosons. For example, fermionic radiation in the lowest harmonic is approximately isotropically distributed around an oscillating solenoid, whereas for bosons the radiation is dipolar. We also investigate the spin polarization of the emitted fermion-antifermion pair. Fermionic radiation from kinks and cusps on cosmic strings is shown to depend linearly on the ultraviolet cut-off, suggesting strong emission at an energy scale comparable to the string energy scale.Comment: 14 pages, 6 figures. Version 2: Expanded discussion on boundary conditions obeyed by Dirac equation mode functions (in Section V B). Acknowledgements and references added. Version 3: Minor changes made in response to referee's comment

Implementing a New Trade Paradigm: Opportunities for Agricultural Trade Regionalism in the Pacific Rim

The objective of this paper is to analyze the economic implications for American food producers, consumers, and society of alternative Pacific Rim free trade region (FIR) configurations.International Relations/Trade,

Faktor-Faktor Yang Berhubungan Dengan Musculoskeletal Disorders (MSDs) Pada Pekerja Home Industry Konveksi X Tangerang Selatan

Penyakit musculoskeletal disorders (MSDs) menjadi penyebab utama dalam Years Lived Disability (YLD) sebesar 17% di seluruh dunia. Penelitian ini dilakukan untuk mengetahui faktor-faktor yang berhubungan dengan kejadian MSDs. Penelitian ini menggunakan metode cross sectional, dengan sampel 30 pekerja konveksi. Teknik pengumpulan data pada penelitian ini menggunakan lembar observasi pengukuran REBA (Rapid Entire Body Assesment), dan kuesioner Nordic Body Map. Berdasarkan penilaian REBA ada 23 pekerja pada tingkat risiko sedang (76,7%), 5 pekerja (16,7%) pada tingkat risiko tinggi dan 2 pekerja pada tingkat risiko rendah (6,7%). Berdasarkan keluhan MSDs sebesar 63,3% mengalami keluhan sedang dan 36,7% pekerja mengalami keluhan ringan. Ada hubungan usia (p value=0,000), masa kerja (p value=0,000), aktivitas fisik (p value=0,009), postur kerja (p value=0,041) dengan kejadian MSDs. Tidak ada hubungan jenis kelamin (p value=0,425), kebiasaan merokok (p value=0,425) dengan kejadian MSDs. Banyak mengeluhkan terkait punggung, pinggang, bahu kanan, dan bokong mereka

A bolometric measurement of the antineutrino mass

High statistics calorimetric measurements of the beta spectrum of 187Re are being performed with arrays of silver perrhenate crystals operated at low temperature. After a modification of the experimental set-up, which allowed to substantially reduce the background of spurious counts and therefore to increase the sensitivity on the electron antineutrino mass, a new measurement with 10 silver perrhenate microbolometers is running since July 2002. The crystals have masses between 250 and 350 micrograms and their average FWHM energy resolution, constantly monitored by means of fluorescence X-rays, is of 28.3 eV at the beta end-point. The Kurie plot collected during 4485 hours x mg effective running time has an end-point energy of 2466.1 +/- 0.8{stat} +/- 1.5 {syst} eV, while the half lifetime of the decay is found to be 43.2 +/- 0.2{stat} +/- 0.1{syst} Gy. These values are the most precise obtained so far for 187Re. From the fit of the Kurie plot we can deduce a value for the squared electron antineutrino mass m(nu)^2 of 147 +/- 237{stat} +/- 90{syst} eV^2. The corresponding 90% C.L. upper limit for m(nu) is 21.7 eV.Comment: 3 pages, 3 figures. Submitted to Phys. Rev. Let

Protein kinases modulate store-operated channels in pulmonary artery smooth muscle cells

<p>Abstract</p> <p>Background</p> <p>This study investigates whether protein kinase G (PKG), protein kinase A (PKA) and protein kinase C (PKC) are involved in the regulatory mechanisms of store-operated channel (SOC) in pulmonary arteries.</p> <p>Methods</p> <p>Pulmonary artery smooth muscle cells (PASMCs) were enzymatically dissociated from rat intralobar pulmonary arteries. Whole cell, cell-attached and inside-out patch-clamp electrophysiology were used to monitor SOCs in isolated PASMCs.</p> <p>Results</p> <p>Initially the Ca²⁺-ATPase inhibitor cyclopiazonic acid (CPA, 10 μM) initiated a whole cell current that was reduced by the SOC blocker SKF-96365 (10 μM). Subsequent work using both cell-attached and whole cell configurations revealed that the PKG and PKA inhibitors, KT5823 (3 μM) and H-89 (10 μM), also stimulated SOC activity; this augmentation was attenuated by the SOC blockers SKF-96365 (10 μM) and Ni²⁺(0.1 mM). Finally using the inside-out configuration, the PKC activator phorbol 12-myristate 13-acetate (PMA, 10 μM) was confirmed to modestly stimulate SOC activity although this augmentation appeared to be more substantial following the application of 10 μM inositol 1,4,5-triphosphate (Ins(1,4,5)P₃).</p> <p>Conclusions</p> <p>SOC activity in PASMCs was stimulated by the inhibition of PKG and PKA and the activation of PKC. Our findings suggest that the SOC could be a substrate of these protein kinases, which therefore would regulate the intracellular concentration of calcium and pulmonary arteriopathy via SOC.</p