707 research outputs found
A tunable line filter polychromator for gas temperature measurements using laser Raman scattering
A proprietary laser line filter spectrograph (LLFS) was modified to test for improved remote measurement of atmospheric temperature by Raman spectroscopy of the rotational bands of N2 and O2. Both grating scan measurements with fixed PMT and polychromator image plane PMT scans with fixed grating setting were made using HeNe and Ar(+) lasers. The LLFS was found to have a laser line rejection ratio at 6A from the laser line and provides resolved rotational Raman spectral display at the polychromator exit plane. Spectral resolution is adequate to measure and correct for background in the Stokes spectrum. It is anticipated that this system should allow measurement of gas or atmospheric temperature to + or - 1 C
Persistent activation of steroidogenesis in adrenocortical cells by photoaffinity labeling of corticotropin receptors
Photolysis of rat adrenocortical cells in the presence of the photoreactive derivative [(2-nitro-5-azidophenylsulfenyl)Trp9]-adrenocorticotropic hormone (2,5-NAPS-ACTH) at 24°C resulted in persistent activation of corticosterone production. The basal rate of steroidogenesis became maximal when photolysis was performed at 24°C but remained the same as that of control cells when irradiation was performed at 0°C. No increase in basal rate was observed with dark controls or cells photolyzed with [(2,4-dinitrophenylsulfenyl)Trp9]ACTH, a photoresistant analog of the hormone. Prephotolyzed 2,5-NAPS-ACTH failed to induce persistent activation. Both ACTH and 2,4-(dinitrophenylsulfenyl)Trp9-ACTH blocked the photo-induced activation of steroidogenesis elicited by 2,5-NAPS-ACTH. Under photolysis conditions which caused the basal rate of steroidogenesis to become maximal, a 3-fold increase in the basal rate of cAMP formation was observed
Fermionic Contributions to the Free Energy of Noncommutative Quantum Electrodynamics at High Temperature
We consider the fermionic contributions to the free energy of noncommutative
QED at finite temperature . This analysis extends the main results of our
previous investigation where we have considered the pure bosonic sector of the
theory. For large values of ( is the magnitude of the
noncommutative parameters) the fermionic contributions decrease the value of
the critical temperature, above which there occurs a thermodynamic instability.Comment: 6 pages, 3 figures. To be published in Physics Letters
Vascular Endothelial Cells Produce Soluble Factors That Mediate the Recovery of Human Hematopoietic Stem Cells after Radiation Injury
AbstractThe risk of terrorism with nuclear or radiologic weapons is considered to be high over the coming decade. Ionizing radiation can cause a spectrum of hematologic toxicities, from mild myelosuppression to myeloablation and death. However, the potential regenerative capacity of human hematopoietic stem cells (HSCs) after radiation injury has not been well characterized. In this study, we sought to characterize the effects of ionizing radiation on human HSCs and to determine whether signals from vascular endothelial cells could promote the repair of irradiated HSCs. Exposure of human bone marrow CD34+ cells to 400 cGy caused a precipitous decline in hematopoietic progenitor cell content and primitive cells capable of repopulating nonobese diabetic/severe combined immunodeficient mice (SCID-repopulating cells), which was not retrievable via treatment with cytokines. Conversely, culture of 400 cGy–irradiated bone marrow CD34+ cells with endothelial cells under noncontact conditions supported the differential recovery of both viable progenitor cells and primitive SCID-repopulating cells. These data illustrate that vascular endothelial cells produce soluble factors that promote the repair and functional recovery of HSCs after radiation injury and suggest that novel factors with radiotherapeutic potential can be identified within this milieu
Replicative capacity of SARS-CoV-2 omicron variants BA.5 and BQ.1.1 at elevated temperatures
新型コロナウイルス・オミクロン株のBA.5系統およびBQ.1.1系統が、高温で増殖しづらいことを解明. 京都大学プレスリリース. 2023-04-27
On the Free Energy of Noncommutative Quantum Electrodynamics at High Temperature
We compute higher order contributions to the free energy of noncommutative
quantum electrodynamics at a nonzero temperature . Our calculation includes
up to three-loop contributions (fourth order in the coupling constant ). In
the high temperature limit we sum all the {\it ring diagrams} and obtain a
result which has a peculiar dependence on the coupling constant. For large
values of ( is the magnitude of the noncommutative
parameters) this non-perturbative contribution exhibits a non-analytic behavior
proportional to . We show that above a certain critical temperature, there
occurs a thermodynamic instability which may indicate a phase transition.Comment: 28 pages, 37 figures. Matches published version in Nuclear Physics
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Web-Based Skin Cancer Prevention Training for Massage Therapists: Protocol for the Massage Therapists Skin Health Awareness, Referral, and Education Study
Background: Skin cancer, the most common cancer in the United States, is costly and potentially deadly. Its burden can be reduced by early detection and prevention activities. The scope of skin cancer requires going beyond traditional health care providers to promote risk reduction. Partnering with the nonbiomedical workforce, such as massage therapists (MTs), may reach more individuals at risk. MTs see much of their clients' skin and are amenable to performing skin cancer risk reduction activities during massage appointments. Objective: The objective of this study is to describe the Massage Therapists Skin Health Awareness, Referral, and Education protocol, presenting an overview of our systematic approach to developing rigorous e-training for MTs to enable them to be partners in skin cancer risk reduction. We also describe procedures for usability and feasibility testing of the training. Methods: We developed an integrated electronic learning system that includes electronic training (e-training) technology, simulated client interactions, online data collection instruments, and in-person assessment of MTs' application of their training. Results: A total of 20 participants nationally scored the e-training as high for usability and satisfaction. We have screened an additional 77 MTs in Arizona for interest and eligibility, and currently have 37 enrolled participants, of whom 32 have completed the Web-based training. Conclusions: The structured and rigorous development approach for this skin cancer risk reduction and brief behavioral intervention e-training for MTs begins to fill a gap in skin cancer risk reduction research. Iterative usability testing of our asynchronous Web-based training resulted in positive participant response. Our e-training approach offers greater learner accessibility, increased convenience, and greater scalability than the few existing programs and has the potential to reach many MTs nationally.Arizona Biomedical Research Centre through the Arizona Department of Health Services [ABRC/ADHS16-162518]; National Institutes of Health-National Cancer Institute (NIH-NCI) Cancer Center Support Grant [P30 CA023074]open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
Third Neighbor Correlators of Spin-1/2 Heisenberg Antiferromagnet
We exactly evaluate the third neighbor correlator and all
the possible non-zero correlators <S^{alpha}_j S^{beta}_{j+1} S^{gamma}_{j+2}
S^{delta}_{j+3}> of the spin-1/2 Heisenberg antiferromagnet in the ground
state without magnetic field. All the correlators are expressed in terms of
certain combinations of logarithm ln2, the Riemann zeta function zeta(3),
zeta(5) with rational coefficients. The results accurately coincide with the
numerical ones obtained by the density-matrix renormalization group method and
the numerical diagonalization.Comment: 4 page
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