1,455 research outputs found
Surface Fluorescence Studies of Tissue Mitochondrial Redox State in Isolated Perfused Rat Lungs
We designed a fiber-optic-based optoelectronic fluorometer to measure emitted fluorescence from the auto-fluorescent electron carriers NADH and FAD of the mitochondrial electron transport chain (ETC). The ratio of NADH to FAD is called the redox ratio (RR = NADH/FAD) and is an indicator of the oxidoreductive state of tissue. We evaluated the fluorometer by measuring the fluorescence intensities of NADH and FAD at the surface of isolated, perfused rat lungs. Alterations of lung mitochondrial metabolic state were achieved by the addition of rotenone (complex I inhibitor), potassium cyanide (KCN, complex IV inhibitor) and/or pentachlorophenol (PCP, uncoupler) into the perfusate recirculating through the lung. Rotenone- or KCN-containing perfusate increased RR by 21 and 30%, respectively. In contrast, PCP-containing perfusate decreased RR by 27%. These changes are consistent with the established effects of rotenone, KCN, and PCP on the redox status of the ETC. Addition of blood to perfusate quenched NADH and FAD signal, but had no effect on RR. This study demonstrates the capacity of fluorometry to detect a change in mitochondrial redox state in isolated perfused lungs, and suggests the potential of fluorometry for use in in vivo experiments to extract a sensitive measure of lung tissue health in real-time
In vivo Detection of Hyperoxia-induced Pulmonary Endothelial Cell Death Using \u3csup\u3e99m\u3c/sup\u3eTc-Duramycin
Introduction 99mTc-duramycin, DU, is a SPECT biomarker of tissue injury identifying cell death. The objective of this study is to investigate the potential of DU imaging to quantify capillary endothelial cell death in rat lung injury resulting from hyperoxia exposure as a model of acute lung injury. Methods Rats were exposed to room air (normoxic) or \u3e 98% O2 for 48 or 60 hours. DU was injected i.v. in anesthetized rats, scintigraphy images were acquired at steady-state, and lung DU uptake was quantified from the images. Post-mortem, the lungs were removed for histological studies. Sequential lung sections were immunostained for caspase activation and endothelial and epithelial cells. Results Lung DU uptake increased significantly (p \u3c 0.001) by 39% and 146% in 48-hr and 60-hr exposed rats, respectively, compared to normoxic rats. There was strong correlation (r2 = 0.82, p = 0.005) between lung DU uptake and the number of cleaved caspase 3 (CC3) positive cells, and endothelial cells accounted for more than 50% of CC3 positive cells in the hyperoxic lungs. Histology revealed preserved lung morphology through 48 hours. By 60 hours there was evidence of edema, and modest neutrophilic infiltrate. Conclusions Rat lung DU uptake in vivo increased after just 48 hours of \u3e 98% O2 exposure, prior to the onset of any substantial evidence of lung injury. These results suggest that apoptotic endothelial cells are the primary contributors to the enhanced DU lung uptake, and support the utility of DU imaging for detecting early endothelial cell death in vivo
Practical reasoning in political discourse: The UK government's response to the economic crisis in the 2008 Pre-Budget Report
This article focuses on practical reasoning in political discourse and argues for a better integration of argumentation theory with critical discourse analysis (CDA). Political discourse and its specific genres (for example, deliberation) primarily involve forms of practical reasoning, typically oriented towards finding solutions to problems and deciding on future courses of action. Practical reasoning is a form of inference from cognitive and motivational premises: from what we believe (about the situation or about means—end relations) and what we want or desire (our goals and values), leading to a normative judgement (and often a decision) concerning action. We offer an analysis of the main argument in the UK government’s 2008 Pre-Budget Report (HM Treasury, 2008) and suggest how a critical evaluation of the argument from the perspective of a normative theory of argumentation (particularly the informal logic developed by Douglas Walton) can provide the basis for an evaluation in terms of characteristic CDA concerns. We are advancing this analysis as a contribution to CDA, aimed at increasing the rigour and systematicity of its analyses of political discourse, and as a contribution to the normative concerns of critical social science
A Simulation Based Study On Visual Inspection Task Performance During Menstrual Cycle
ABSTRACT
This research was conducted to study women performances in visual inspection task during menstrual cycle. The participants were ten female students with regular cycle (28 days). Factory noise (80 dBA) that recorded from its original location was added to make the simulation area became more likely the real situation. The intervals observed were on the day 2, day 14, and day 23 of their cycle. Signal Detection Theory was used to measure the accuracy of inspection taskThe results revealed that menstrual cycle and noise presence affecting the accuracy (represent with sensitivity) but there were no interaction between those two factors (menstrual status and factory noise).
Keywords: Menstrual Cycle, Visual Inspection, Signal Detection Theor
Beta decay of 115-In to the first excited level of 115-Sn: Potential outcome for neutrino mass
Recent observation of beta decay of 115-In to the first excited level of
115-Sn with an extremely low Q_beta value (Q_beta ~ 1 keV) could be used to set
a limit on neutrino mass. To give restriction potentially competitive with
those extracted from experiments with 3-H (~2 eV) and 187-Re (~15 eV), atomic
mass difference between 115-In and 115-Sn and energy of the first 115-Sn level
should be remeasured with higher accuracy (possibly of the order of ~1 eV).Comment: 9 pages, 3 figures; talk at the NANP'05 Conferenc
Kajian Kerentanan Fisik, Sosial, dan Ekonomi Pesisir Samas Kabupaten Bantul terhadap Erosi Pantai
Pesisir Samas merupakan salah satu objek pariwisata yang memiliki infrastruktur yang rentan terancam keberlanjutan perkembangannya jika erosi pantai tidak segera diatasi. Penelitian ini bertujuan untuk mengkaji tingkat kerentanan dan mengkaji kapasitas masyarakat dalam menghadapi erosi pantai di Daerah Kepesisiran Samas. Penilaian kerentanan wilayah dilakukan dengan metode SMCE dan penilaian kerentanan di tingkat rumah tangga dilakukan dengan metode pengharkatan. Penilaian tingkat kapasitas masyarakat dilakukan menggunakan metode skoring hasil wawancara terstruktur. Hasil penilaian kerentanan wilayah menunjukkan bahwa pada ketiga skenario yaitu skenario fisik, sosial ekonomi, dan equal memiliki nilai yang sama yang menunjukkan bahwa Desa Srigading memiliki nilai kerentanan yang lebih tinggi daripada Desa Gadingsari. Hasil penilaian kerentanan rumah tangga pada parameter fisik, sosial, dan ekonomi secara berurutan menunjukkan 50%, 8,93%, dan 46,43% rumah tangga memiliki tingkat kerentanan tinggi. Hasil penilaian kapasitas masyarakat menunjukkan penduduk di Daerah Kepesisiran Samas memiliki tingkat kapasitas yang tergolong sedang
Thomas-Ehrman shifts in nuclei around ^{16}O and role of residual nuclear interaction
The asymmetry in the energy spectra between mirror nuclei (the Thomas-Ehrman
shifts) around O is investigated from a phenomenological viewpoint. The
recent data on proton-rich nuclei indicates that the residual nuclear
interaction is reduced for the loosely bound s-orbit by as much as 30%, which
originates in the broad radial distribution of the proton single-particle wave
function.Comment: to appear in Phys. Lett. B, with 3 eps figure
Treatment of the Intrinsic Hamiltonian in Particle-Number Nonconserving Theories
We discuss the implications of using an intrinsic Hamiltonian in theories
without particle-number conservation, e.g., the Hartree-Fock-Bogoliubov
approximation, where the Hamiltonian's particle-number dependence leads to
discrepancies if one naively replaces the particle-number operator by its
expectation value. We develop a systematic expansion that fixes this problem
and leads to an a posteriori justification of the widely-used one- plus
two-body form of the intrinsic kinetic energy in nuclear self-consistent field
methods. The expansion's convergence properties as well as its practical
applications are discussed for several sample nuclei.Comment: 6 pages, 5 figure
Modified Bethe-Weizsacker mass formula with isotonic shift and new driplines
Nuclear masses are calculated using the modified Bethe-Weizsacker mass
formula in which the isotonic shifts have been incorporated. The results are
compared with the improved liquid drop model with isotonic shift. Mass excesses
predicted by this method compares well with the microscopic-macroscopic model
while being much more simple. The neutron and proton drip lines have been
predicted using this modified Bethe-Weizsacker mass formula with isotonic
shifts.Comment: 9 pages including 2 figure
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