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1.
Spontaneous mutations in the EEF1A2 gene cause epilepsy and severe neurological disabilities in children. The crystal structure of eEF1A2 protein purified from rabbit skeletal muscle reveals a post-translationally modified dimer that provides information about the sites of interaction with numerous binding partners, including itself, and maps these mutations onto the dimer and tetramer interfaces. The spatial locations of the side chain carboxylates of Glu301 and Glu374, to which phosphatidylethanolamine is uniquely attached via an amide bond, define the anchoring points of eEF1A2 to cellular membranes and interorganellar membrane contact sites. Additional bioinformatic and molecular modeling results provide novel structural insight into the demonstrated binding of eEF1A2 to SH3 domains, the common MAPK docking groove, filamentous actin, and phosphatidylinositol-4 kinase IIIβ. In this new light, the role of eEF1A2 as an ancient, multifaceted, and articulated G protein at the crossroads of autophagy, oncogenesis and viral replication appears very distant from the “canonical” one of delivering aminoacyl-tRNAs to the ribosome that has dominated the scene and much of the thinking for many decades.  相似文献   
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The change of magnetoelastic properties after thermal treatments has been investigated for two groups of metallic glasses. (Fe79Co21)75+xSi15−1.4xB10+0.4x (x (at.%)=0, 2, 4, 6, 8, 10) has been studied both in the as-prepared state and after thermal annealing in an applied magnetic field, to achieve a particular domain structure, at temperatures well below the crystallization temperatures. Changes in the ΔE effect, magnetomechanical coupling (k) and internal friction coefficient (Q−1) are reported, reaching values of about 60% of the saturation value ES. Fe64Ni10Nb3Cu1Si13B9 alloys annealed in vacuum for 1 h in the temperature range 350–550 °C showed maximum values of the ΔE effect and k of 61% and 0.85, respectively, accompanied by a minimum value of Q of around 2 for the sample annealed at 460 °C. These variations are related to the progress of nanocrystalization. The properties achieved are among the best reported for magnetomechanical applications.  相似文献   
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Prevalence rates of trauma and posttraumatic stress disorder (PTSD) were estimated from a probability sample of 2,509 adults from 4 cities in Mexico. PTSD was assessed according to Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 1994) criteria using the Composite International Diagnostic Interview (CIDI; WHO, 1997). Lifetime prevalence of exposure and PTSD were 76% and 11.2%, respectively. Risk for PTSD was highest in Oaxaca (the poorest city), persons of lower socioeconomic status, and women. Conditional risk for PTSD was highest following sexual violence, but nonsexual violence and traumatic bereavement had greater overall impact because of their frequency. Of lifetime cases, 62% became chronic; only 42% received medical or professional care. The research demonstrates the importance of expanding the epidemiologic research base on trauma to include developing countries around the world. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The ability of mono-, di-, tri-and tetra-hydroxyflavones (7-and 3-hy-droxyflavones, 7, 8-dihydroxyflavone, baicalein and fisetin) to act as photoprotectors against singlet molecular oxygen [O2g)]-initiated photooxidation of fats has been established by a kinetic study. The overall quenching rate constants for a series of five hydroxyflavones perfectly parallel their respective behaviour as inhibitors of the sensitized photooxidation of linoleic acid. The best antioxidative effect was exerted by 7-hydroxyflavone which does not chemically react with O2(1Δg). Nevertheless for the remaining flavonoids of the series, the physical deactivation of O2(1Δg) largely prevails over the chemical process. As for the cases of phenols and related hydroxy-aromatic derivatives, the ionization of the -OH group in the flavones, dramatically accelerates the rate of photooxidation. Under these conditions, the 7-hydroxyflavone also reacts effectively with O2(1Δg). Given that flavonoids are natural oil components, this medium effect should be taken into account during the oil-refining process, in order to avoid the flavonoid photodestruction.  相似文献   
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OBJECTIVE: Retrospective study of urological complications in our series of reno-pancreatic transplants. MATERIAL AND METHODS: Between February 1983 and May 1994 our group has conducted 93 RPT, 80 of which, mean age 36 +/- 6 years (24-54 years), are studied in this paper: 57 male and 23 female with an average time in dialysis of 20 +/- 15 months (0-84 months) and diabetes evolution of 21 +/- 5 years (11-37 years). RESULTS: Actuarial annual survival of patient, renal graft and pancreatic graft has been 85%, 79% and 74% respectively. Haematuria: 25% incidence, with graft pancreatitis etiology in 16 cases, rejection in 8 and urinary fistula in 6. Urinary infection: 85% incidence, symptomatic in 23 patients (29%) and asymptomatic in the remaining cases. Dysuria, urethritis and urethral stenosis: 14 patients, all male, most with both conditions associated. Reconversion of pancreatic exocrine secretion by intestinal route was performed in 7 patients. Urinary fistula: secondary to surgery in 9 cases and rejection in 4. Etiology of one case remained unknown. In 4 cases it was resolved with conservative treatment, and with surgical correction in 8. One patient required pancreatic transplantectomy and one patient died of AMI. CONCLUSIONS: Urological complication in RPT account for a significant morbidity, urinary fistula being the one with greater repercussion on the patient and pancreatic graft survival.  相似文献   
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We report the appearance of a novel self-assembling of a fraction of single-wall carbon nanotubes (SWCNT) within a SWCNT-polymer nanocomposite subjected to flow fields upon injection molding processing. By combining X-ray diffraction and Raman spectroscopy techniques, both working on a microfocus fashion, we probe that a fraction of the thinnest SWCNT self-assembles into a rectangular lattice in the sample regions where the shear stress induces the highest levels of nanotube aggregation. Additionally, we demonstrate that a modest amount in weight of nanotubes is enough to template the morphology of crystallization during flow providing a method to obtain a highly desirable fiber-like morphology.  相似文献   
10.
Holistic schedulability analysis for multipacket messages in AFDX networks   总被引:1,自引:0,他引:1  
The ARINC-664, Part 7 (AFDX) standard defines a communication network based on Ethernet and the UDP/IP protocols. Contrary to general-purpose Ethernet, the timing behavior in AFDX is deterministic due to the use of special network switches and end systems with static routing tables and traffic policing at the sending end through mechanisms called virtual links. Even though the latencies in this network are bounded, there are scheduling and contention effects that need to be analyzed. In this paper we develop a response-time analysis for multipacket messages transmitted through an AFDX network including the scheduling of the virtual links and sub-virtual links, and also the contention in the end systems and in the switches. This analysis allows us to obtain worst-case latencies and output jitter for the network messages with a precise modeling of the sending and receiving ends. These results can be integrated in a holistic approach with the response time analysis of the threads in the processing nodes to obtain end-to-end response times in heterogeneous distributed systems.  相似文献   
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