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Physical vapor deposition of organic molecules can produce glasses with high kinetic stability and low enthalpy. Previous experiments utilizing wide-angle x-ray scattering (WAXS) have shown that, relative to the ordinary glasses prepared by cooling the supercooled liquid, such glasses exhibit excess scattering characteristic of anisotropic packing. We have used vapor deposition to prepare glasses of four isomers of tris-naphthylbenzene (TNB), and measured both the WAXS patterns and the kinetic stability. While vapor-deposited glasses of all four TNB isomers exhibit high and nearly uniform kinetic stability, the level of excess scattering varies significantly. In addition, for α,α,β-TNB, glasses of essentially identical kinetic stability can have excess scattering levels that vary by a factor of two. These results indicate that anisotropic packing is not the source of kinetic stability in vapor-deposited glasses but rather a secondary feature that depends upon the chemical structure of the glass-forming molecules. We also show that the time required for these stable vapor-deposited glasses to transform into the supercooled liquid greatly exceeds the structural relaxation time τα of the liquid and scales approximately as τα0.6. The kinetic stability of the vapor-deposited TNB glasses matches that expected for ordinary glasses that have been aged for 102 to 107 years. [ABSTRACT FROM AUTHOR]

Objective: Adenosine deaminase catalyzes the conversion of adenosine and deoxyadenosine to inosine and deoxyinosine, respectively. Because raising adenosine concentration can affect several physiological processes we studied the effect of a selection of cardiological drugs on adenosine deaminase activity in red blood cells and rabbit plasma after 21 days administration. Methods and Results: We determined the activity of adenosine deaminase isoenzymes (ADA1 and ADA2). Simvastatin, aspirin, metoprolol, and isosorbide mononitrate significantly decreased plasma total adenosine activity (by 50%, 34%, 29%, and 19%, respectively; P < .05 to P < .001) mainly by decreasing the activity of ADA2. Conclusions: As a consequence of decreased ADA2 activity , the half-life of adenosine will be lengthened. This may, at least in part, explain some of the beneficial effects of analyzed drugs. Our results might be clinically relevant in patients with coronary artery disease, acute coronary syndromes, heart failure, or stroke where the investigated drugs are commonly used. However, our results should be confirmed in large studies in humans. [ABSTRACT FROM AUTHOR]

Objective: Adenosine deaminase catalyzes the conversion of adenosine and deoxyadenosine to inosine and deoxyinosine, respectively. Because raising adenosine concentration can affect several physiological processes we studied the effect of a selection of cardiological drugs on adenosine deaminase activity in red blood cells and rabbit plasma after 21 days administration. Methods and Results: We determined the activity of adenosine deaminase isoenzymes (ADA[sub1] and ADA[sub2]). Simvastatin, aspirin, metoprolol, and isosorbide mononitrate significantly decreased plasma total adenosine activity (by 50%, 34%, 29%, and 19%, respectively; P < .05 to P < .001) mainly by decreasing the activity of ADA[sub2]. Conclusions: As a consequence of decreased ADA[sub2] activity , the half-life of adenosine will be lengthened. This may, at least in part, explain some of the beneficial effects of analyzed drugs. Our results might be clinically relevant in patients with coronary artery disease, acute coronary syndromes, heart failure, or stroke where the investigated drugs are commonly used. However, our results should be confirmed in large studies in humans. [ABSTRACT FROM AUTHOR]

An essay is presented on what role different traditions played in the American founding especially Germanic traditions. It offers the various attributes of the German traditions that impressed America's Founders including virtues like courage, public debating and love for freedom and the common law's role in the American founding. The author discusses how religious beliefs like Protestantism which originated in Germany shaped the thinking of the colonists who were traditionalists by nature.

Photolysis (λ > 543 nm) of 3-thienyldiazomethane (1), matrix isolated in Ar or N2 at 10 K, yields triplet 3-thienylcarbene (13) and α-thial-methylenecyclopropene (9). Carbene 13 was characterized by IR, UV/vis, and EPR spectroscopy. The conformational isomers of 3-thienylcarbene (s-E and s-Z) exhibit an unusually large difference in zero-field splitting parameters in the triplet EPR spectrum (∣D/hc∣ = 0.508 cm-1, ∣E/hc∣ = 0.0554 cm-1; ∣D/hc∣ = 0.579 cm-1, ∣E/hc∣ = 0.0315 cm-1). Natural Bond Orbital (NBO) calculations reveal substantially differing spin densities in the 3-thienyl ring at the positions adjacent to the carbene center, which is one factor contributing to the large difference in D values. NBO calculations also reveal a stabilizing interaction between the sp orbital of the carbene carbon in the s-Z rotamer of 13 and the antibonding σ orbital between sulfur and the neighboring carbon-an interaction that is not observed in the s-E rotamer of 13. In contrast to the EPR spectra, the electronic absorption spectra of the rotamers of triplet 3-thienylcarbene (13) are indistinguishable under our experimental conditions. The carbene exhibits a weak electronic absorption in the visible spectrum (λmax = 467 nm) that is characteristic of triplet arylcarbenes. Although studies of 2-thienyldiazomethane (2), 3-furyldiazomethane (3), or 2-furyldiazomethane (4) provided further insight into the photochemical interconversions among C5H4S or C5H4O isomers, these studies did not lead to the spectroscopic detection of the corresponding triplet carbenes (2-thienylcarbene (11), 3-furylcarbene (23), or 2-furylcarbene (22), respectively). [ABSTRACT FROM AUTHOR]

Presents a study on the effects of aluminum chloride on selected biochemical parameters and oxidative-antioxidative balance of experimental animals. Effects of aluminum on living organisms; Impact of aluminum chloride on the biochemical parameters and oxidative stress biomarkers of experimental animals; Details of the study.

This essay addresses two problems in interpreting General Douglas MacArthur's speech on May 12, 1962 as he received the Silvanus Thayer Award at West Point, namely if it was improvised and if it accurately quoted philosopher Plato's views on war. The author concludes that it was improvised because it was delivered without notes and was created on the day he delivered it using traditional themes and topics. He also argues that the general remembered Plato's views on war but paraphrased them in author George Santayana's words in "Soliloquies in England."

Objective: The aim of this research was to study childbirth experience for the primiparae couple and their emotional state in early post-partum. Patients and methods: Thirty-three couples were interviewed 2 days after the birth. A questionnaire on childbirth experience and the EPDS were carried out. Results: According to the results, mothers feel less satisfied, less calm, more useful and suffer more than fathers. Moreover, they consider father''s participation more active and more supportive than themselves assess it. Experience of childbirth is linked with parent''s emotional state in early postpartum. Discussion and conclusion: These results stress the importance to take into account the woman, the men and the couple as three separate and singular units and to create space for dialogue before and after childbirth. [Copyright &y& Elsevier]

Objective: The aim of this research was to study childbirth experience for the primiparae couple. Patients and methods: Thirty-three couples were interviewed two days after the birth in maternities. Results: For mothers, the presence of their husbands is a support whereas men mentioned a feeling of helplessness. Discussion and conclusion: These results point out the need to accompany mothers and fathers during birth preparation to make this experience to be the most satisfying for both members of couple. [Copyright &y& Elsevier]

The reaction of the chemical warfare agent VX with hydroxide and hydroperoxide has been studied using a combination of correlated molecular orbital and density functional theory. It is found that the alkaline hydrolysis leads to a mixture of neurotoxic and non-toxic products while hydroperoxidolysis leads to exclusive formation of non-toxic products. Natural bond orbital (NBO) analysis is used to rationalize the observation that hydroxide will attack opposite the alkoxide ligand, while hydroperoxide will attack opposite the thiolate. The current results are in good agreement with previous experimental and computational work and serve to clarify the mechanism for destruction of this highly potent nerve agent. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Profiles poet and conservative Alfred Edward Housman. Poem written by Housman that exemplified his belief that human desires can change the world; Political and social conservatism of Housman; Criticisms against Housman's "Last Poems"; Influence of the poet's loss of faith on his Cyrenaic position.

Discusses the subject of language study and tradition in the 21st century. Challenges facing anyone committed to forwarding the study of language and literature; Manifestation of multiculturalism in education.

Discusses how the classics, not just Greece and Rome where they came from, should be studied from an early age, in addition to other courses taught. Liberal arts education in our society should be grounded in the study of languages, literatures,history and philosophy of ancient Greece and Rome. Foreign scholars filling American gaps in research; Blaming current woes on the sixties; Computers should be taught early; Physical scientists; More.

Secondary ion mass spectrometry has been used to characterize translational motion in vapor-deposited glasses of indomethacin (IMC) and α,α,β-tris-naphthylbenzene (TNB). Vapor deposition onto substrates at ∼0.99 Tg produced ordinary glasses that evolve according to Fickian diffusion during annealing. The resulting self-diffusion coefficients for the supercooled liquids are in good agreement with previous reports. Deposition onto substrates at 0.85 Tg produced highly stable glasses that transform with a propagating front mechanism. In contrast to previous reports, the liquid produced by this transformation has the same translational mobility as the ordinary supercooled liquid; we associate this result with lower impurity levels in the current samples. The front velocities for both TNB and IMC stable glasses are very similar functions of the translational self-diffusion coefficients of the supercooled liquids, consistent with view that the growth front velocity is controlled by mobility in the liquid adjacent to the stable glass. [ABSTRACT FROM AUTHOR]