97 research outputs found
Clamping assembly for inertial components Patent
Inertial component clamping assembly design for spacecraft guidance and control system mountin
Stereochemistry and Twisted Crystals
This review article discusses a link between stereochemistry and structural and morphological chirality. We present the remarkably frequent, but less often reported, growth of twisted crystals and discuss the reasons for their formation and ways to favor their growth. The more commonly encountered conglomerates and racemic compounds can be formed by achiral molecules, but the emergence of morphological chirality is often not considered in this context and perhaps deserves attention. Twisted crystals are known for a wide variety of materials, molecular and macromolecular, complexes and oxides, and so on. In growing crystals, twisting of lamellae because of strain generated during growth eventually unwinds in larger objects, and may not be detected. This kind of chiral morphology arising from low symmetry growth, and the challenges and opportunities for research in the area, are highlighted. In particular, the link between structural bending in supramolecular aggregates in solution or at interfaces, chiral nanofilaments in liquid crystals, and chiral polymers, is discussed
Runnin\u27 Wild / music by Harrington Harris; words by Joe Grey and Leo Wood
An Ebony Jazz Tune (Cover). Key of Bb. Cover: a caricature of a man running; [Back page missing]; Publisher: Leo Feist Inc. (New York); Also includes Dusting the Keys (J. Edward Killalea and Edward B. Claypoole) and River Shannon Moon (Walter Wallace Smith)https://egrove.olemiss.edu/sharris_d/1043/thumbnail.jp
Ground and Excited States of Bis‐4‐Methoxybenzyl‐Substituted Diketopyrrolopyrroles: Spectroscopic and Electrochemical Studies
A series of symmetrically bis‐4‐methoxybenzyl (4MB) N‐substituted 1,4‐diketopyrrolo[3,4‐c]pyrrole (DPP) derivatives have been synthesized. The 4MB unit makes the DPP core soluble, and shows subtle modification of up to 0.2 eV in ground and excited states of the core when compared with related alkyl derivatives. Absorption and emission spectroscopy, as well as electrochemical and computational methods have been employed to prove the importance of the peripheral aryl units on the donor/ acceptor properties of the molecules. The 4MB products are highly fluorescent (quantum yields approaching 100 % in solution), with a unique distribution of frontier states shown by spectroelectrochemistry. The solid‐state fluorescence correlates with the X‐ray crystal structures of the compounds, a Stokes shift of approximately 80 nm is seen for two of the compounds. The frontier energy levels show that this subtle substitutional change could be of future use in molecular energy level tailoring in these, and related, materials for organic (opto)electronics
Fenitrothion: toxicokinetics and toxicologic evaluation in human volunteers.
An unblinded crossover study of fenitrothion 0.18 mg/kg/day [36 times the acceptable daily intake (ADI)] and 0.36 mg/kg/day (72 X ADI) administered as two daily divided doses for 4 days in 12 human volunteers was designed and undertaken after results from a pilot study. On days 1 and 4, blood and urine samples were collected for analysis of fenitrothion and its major metabolites, as well as plasma and red blood cell cholinesterase activities, and biochemistry and hematology examination. Pharmacokinetic parameters could only be determined at the higher dosage, as there were insufficient measurable fenitrothion blood levels at the lower dosage and the fenitrooxone metabolite could not be measured. There was a wide range of interindividual variability in blood levels, with peak levels achieved between 1 and 4 hr and a half-life for fenitrothion of 0.8-4.5 hr. Although based on the half-life, steady-state levels should have been achieved; the area under the curve (AUC)(0-12 hr) to AUC(0-(infinity) )ratio of 1:3 suggested accumulation of fenitrothion. There was no significant change in plasma or red blood cell cholinesterase activity with repeated dosing at either dosage level of fenitrothion, and there were no significant abnormalities detected on biochemical or hematologic monitoring
International outbreak of Salmonella Oranienburg due to German chocolate
BACKGROUND: This report describes a large international chocolate-associated Salmonella outbreak originating from Germany. METHODS: We conducted epidemiologic investigations including a case-control study, and food safety investigations. Salmonella (S.) Oranienburg isolates were subtyped by the use of pulsed-field gel electrophoresis (PFGE). RESULTS: From 1 October 2001 through 24 March 2002, an estimated excess of 439 S. Oranienburg notifications was registered in Germany. Simultaneously, an increase in S. Oranienburg infections was noted in other European countries in the Enter-net surveillance network. In a multistate matched case-control study in Germany, daily consumption of chocolate (matched odds ratio [MOR]: 4.8; 95% confidence interval [CI]: 1.3–26.5), having shopped at a large chain of discount grocery stores (MOR: 4.2; CI: 1.2–23.0), and consumption of chocolate purchased there (MOR: 5.0; CI: 1.1–47.0) were associated with illness. Subsequently, two brands from the same company, one exclusively produced for that chain, tested positive for S. Oranienburg. In two other European countries and in Canada chocolate from company A was ascertained that also contained S. Oranienburg. Isolates from humans and from chocolates had indistinguishable PFGE profiles. No source or point of contamination was identified. Epidemiological identification of chocolate as a vehicle of infections required two months, and was facilitated by proxy measures. CONCLUSIONS: Despite the use of improved production technologies, the chocolate industry continues to carry a small risk of manufacturing Salmonella-containing products. Particularly in diffuse outbreak-settings, clear associations with surrogates of exposure should suffice to trigger public health action. Networks such as Enter-net have become invaluable for facilitating rapid and appropriate management of international outbreaks
International Spread of Multidrug-resistant Salmonella Schwarzengrund in Food Products
This serovar was isolated from persons, food, and food animals in Thailand, Denmark, and the United States
Seeing through the haze: a daily diary study examining potential mechanisms underlying cannabis use and psychotic-like experiences in young adults
vAbstractAs cannabis continues to be liberalized across the world, researchers have called for the utilization of alternative methodologies to advance our understandingof the adverse effects of cannabis. In particular, it still remains unclear what momentary mechanisms underlie the well-established vulnerability associated with psychosis and subclinical psychotic-like experiences (PLEs) in cannabis users. Thus, a daily diary study was conducted to examine the cannabis and PLE relationship and assess whether day-to-day fluctuations in negative affect and the facets of self-regulation; emotion-dysregulation, sensation-seeking, impulsivity and mindfulness (measured by the Momentary Self-Regulation Questionnaire), moderate the relationship. Eighty-nine young adult past month cannabis users with varying degrees of recent PLEs completed daily surveys over 10-days, with high completion rates (85%). Multilevel modelling analyses indicated that daily cannabis use quantity predicted same-day PLEs, as did daily levels of heightened negative affect and emotion-dysregulation. Although, heightened negative affect, emotion-dysregulation and impulsivity, and diminished mindfulness were characteristic of cannabis users with PLEs over the study period, only daily levels of emotion-dysregulation moderated the daily cannabis use and same-day PLE association. This is one of the first diary studies to investigate potential psychological mechanisms underlying PLE vulnerability in young cannabis users. Results implicating heightened daily levels of emotion-dysregulation in PLEs, cannabis use and the relationship between the two highlight the importance of future intervention research targeting thismechanism. Future research is also required to determine the direction of the relationship between cannabis use, emotion-dysregulation and PLE
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