1,334 research outputs found
Gaseous Electronics
Contains reports on two research projects.Joint Services Electronics Programs (U. S. Army, U. S. Navy, and U. S. Air Force) under Contract DA 28-043-AMC-02536(E
Effects of telmisartan and ramipril on adiponectin and blood pressure in patients with type 2 diabetes
<b>Background:</b>
Adiponectin is secreted by adipose tissue and may play a role in cardiovascular disease. We examined adiponectin levels in patients with type 2 diabetes who participated in the Telmisartan vs. Ramipril in Renal Endothelial Dysfunction (TRENDY) study.
<b>Methods</b>
A total of 87 patients were assessed at baseline and following 9 weeks treatment with the angiotensin-receptor blocker telmisartan (final dose, 80 mg; n = 45) or the angiotensin-converting enzyme inhibitor ramipril (final dose, 10 mg; n = 42). Adiponectin levels were measured in plasma by radioimmunoassay.
<b>Results:</b>
Adiponectin levels were inversely correlated with systolic (SBP; r = -0.240, P < 0.05) and diastolic (DBP; r = -0.227, P < 0.05) blood pressure at baseline and following treatment with telmisartan or ramipril (SBP: r = -0.228, P < 0.05; DBP: r = -0.286, P < 0.05). Changes in adiponectin levels were related to changes in SBP (r = -0.357, P < 0.01) and DBP (r = -0.286, P < 0.01). There was a significant increase in adiponectin levels in the telmisartan (0.68 (95% confidence interval (CI), 0.27 to 1.10) <sup>µ</sup>g/ml, P < 0.01) but not in the ramipril group (0.17 (95% CI, -0.56 to 0.90) <sup>µ</sup>g/ml, P = 0.67). Blood pressure reduction in the telmisartan group (DeltaSBP: -13.5 (95% CI, -17.0 to -10.0) mm Hg; ΔDBP: -7.6 (95% CI, -9.8 to -5.3) mm Hg, each P < 0.001) was significantly (P less than or equal to 0.01 for SBP and P < 0.01 for DBP) greater than in the ramipril group (ΔSBP: -6.1 (95% CI, -6.2 to -2.0) mm Hg; ΔDBP: -2.7 (95% CI, -5.0 to -0.5) mm Hg; P < 0.01 and P < 0.05, respectively).
<b>Conclusion:</b>
Adiponectin is correlated with blood pressure in patients with type 2 diabetes. Whether increased adiponectin contributes to the blood pressure–lowering effect of telmisartan needs further study
HOx and NOx production in oxidation flow reactors via photolysis of isopropyl nitrite, isopropyl nitrite-d(7), and 1,3-propyl dinitrite at lambda=254, 350, and 369 nm
Oxidation flow reactors (OFRs) are an emerging technique for studying the formation and oxidative aging of organic aerosols and other applications. In these flow reactors, hydroxyl radicals (OH), hydroperoxyl radicals (HO2), and nitric oxide (NO) are typically produced in the following ways: photolysis of ozone (O-3) at), = 254 nm, photolysis of H2O at), = 185 nm, and via reactions of O(D-1) with H2O and nitrous oxide (N2O); O(D-1) is formed via photolysis of O-3 at = 254 nm and/or N2O at = 185 nm. Here, we adapt a complementary method that uses alkyl nitrite photolysis as a source of OH via its production of HO2 and NO followed by the reaction NO + HO2 -> NO2 + OH. We present experimental and model characterization of the OH exposure and NO, levels generated via photolysis of C3 alkyl nitrites (isopropyl nitrite, perdeuterated isopropyl nitrite, 1,3-propyl dinitrite) in the Potential Aerosol Mass (PAM) OFR as a function of photolysis wavelength (7, = 254 to 369 nm) and organic nitrite concentration (0.5 to 20 ppm). We also apply this technique in conjunction with chemical ionization mass spectrometer measurements of multifunctional oxidation products generated following the exposure of a-Pinene to HO, and NO, obtained using both isopropyl nitrite and O-3 + H2O + N2O as the radical precursors.Peer reviewe
A vision of the future for BMC Medicine: serving science, medicine and authors
In June 2009, BMC Medicine received its first official impact factor of 3.28 from Thomson Reuters. In recognition of this landmark event, the BMC Medicine editorial team present and discuss the vision and aims of the journal
A quasi classical approach to electron impact ionization
A quasi classical approximation to quantum mechanical scattering in the
Moeller formalism is developed. While keeping the numerical advantage of a
standard Classical--Trajectory--Monte--Carlo calculation, our approach is no
longer restricted to use stationary initial distributions. This allows one to
improve the results by using better suited initial phase space distributions
than the microcanonical one and to gain insight into the collision mechanism by
studying the influence of different initial distributions on the cross section.
A comprehensive account of results for single, double and triple differential
cross sections for atomic hydrogen will be given, in comparison with experiment
and other theories.Comment: 21 pages, 10 figures, submitted to J Phys
BLOOM+1: Adding Language Support to BLOOM for Zero-Shot Prompting
The BLOOM model is a large publicly available multilingual language model, but its pretraining was limited to 46 languages. To extend the benefits of BLOOM to other languages without incurring prohibitively large costs, it is desirable to adapt BLOOM to new languages not seen during pretraining. In this work, we apply existing language adaptation strategies to BLOOM and benchmark its zero-shot prompting performance on eight new languages in a resource-constrained setting. We find language adaptation to be effective at improving zero-shot performance in new languages. Surprisingly, we find that adapter-based finetuning is more effective than continued pretraining for large models. In addition, we discover that prompting performance is not significantly affected by language specifics, such as the writing system. It is primarily determined by the size of the language adaptation data. We also add new languages to BLOOMZ, which is a multitask finetuned version of BLOOM capable of following task instructions zero-shot. We find including a new language in the multitask fine-tuning mixture to be the most effective method to teach BLOOMZ a new language. We conclude that with sufficient training data language adaptation can generalize well to diverse languages. Our code is available at https://github.com/bigscience-workshop/multilingual-modeling
Pulsed Feedback Defers Cellular Differentiation
Environmental signals induce diverse cellular differentiation programs. In certain systems, cells defer differentiation for extended time periods after the signal appears, proliferating through multiple rounds of cell division before committing to a new fate. How can cells set a deferral time much longer than the cell cycle? Here we study Bacillus subtilis cells that respond to sudden nutrient limitation with multiple rounds of growth and division before differentiating into spores. A well-characterized genetic circuit controls the concentration and phosphorylation of the master regulator Spo0A, which rises to a critical concentration to initiate sporulation. However, it remains unclear how this circuit enables cells to defer sporulation for multiple cell cycles. Using quantitative time-lapse fluorescence microscopy of Spo0A dynamics in individual cells, we observed pulses of Spo0A phosphorylation at a characteristic cell cycle phase. Pulse amplitudes grew systematically and cell-autonomously over multiple cell cycles leading up to sporulation. This pulse growth required a key positive feedback loop involving the sporulation kinases, without which the deferral of sporulation became ultrasensitive to kinase expression. Thus, deferral is controlled by a pulsed positive feedback loop in which kinase expression is activated by pulses of Spo0A phosphorylation. This pulsed positive feedback architecture provides a more robust mechanism for setting deferral times than constitutive kinase expression. Finally, using mathematical modeling, we show how pulsing and time delays together enable “polyphasic” positive feedback, in which different parts of a feedback loop are active at different times. Polyphasic feedback can enable more accurate tuning of long deferral times. Together, these results suggest that Bacillus subtilis uses a pulsed positive feedback loop to implement a “timer” that operates over timescales much longer than a cell cycle
On the reliability of the theoretical internal conversion coefficients
Possible sources of uncertainties in the calculations of the internal
conversion coefficients are studied. The uncertainties induced by them are
estimated.Comment: 16 pages (including 3 figures inserted by 'epsfig' macro
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