957 resultados para Safety glass.


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We study numerically the out-of-equilibrium dynamics of the hypercubic cell spin glass in high dimensionalities. We obtain evidence of aging effects qualitatively similar both to experiments and to simulations of low-dimensional models. This suggests that the Sherrington-Kirkpatrick model as well as other mean-field finite connectivity lattices can be used to study these effects analytically.

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Refractory status epilepticus (RSE)-that is, seizures resistant to at least two antiepileptic drugs (AEDs)-is generally managed with barbiturates, propofol, or midazolam, despite a low level of evidence (Rossetti, 2007). When this approach fails, the need for alternative pharmacologic and nonpharmacologic strategies emerges. These have been investigated even less systematically than the aforementioned compounds, and are often used, sometimes in succession, in cases of extreme refractoriness (Robakis & Hirsch, 2006). Several possibilities are reviewed here. In view of the marked heterogeneity of reported information, etiologies, ages, and comedications, it is extremely difficult to evaluate a given method, not to say to compare different strategies among them. Pharmacologic Approaches Isoflurane and desflurane may complete the armamentarium of anesthetics,' and should be employed in a ''close'' environment, in order to prevent intoxication of treating personnel. c-Aminobutyric acid (GABA)A receptor potentiation represents the putative mechanism of action. In an earlier report, isoflurane was used for up to 55 h in nine patients, controlling seizures in all; mortality was, however, 67% (Kofke et al., 1989). More recently, the use of these inhalational anesthetics was described in seven subjects with RSE, for up to 26 days, with an endtidal concentration of 1.2-5%. All patients required vasopressors, and paralytic ileus occurred in three; outcome was fatal in three patients (43%) (Mirsattari et al., 2004). Ketamine, known as an emergency anesthetic because of its favorable hemodynamic profile, is an N-methyl-daspartate (NMDA) antagonist; the interest for its use in RSE derives from animal works showing loss of GABAA efficacy and maintained NMDA sensitivity in prolonged status epilepticus (Mazarati & Wasterlain, 1999). However, to avoid possible neurotoxicity, it appears safer to combine ketamine with GABAergic compounds (Jevtovic-Todorovic et al., 2001; Ubogu et al., 2003), also because of a likely synergistic effect (Martin & Kapur, 2008). There are few reported cases in humans, describing progressive dosages up to 7.5 mg/kg/h for several days (Sheth & Gidal, 1998; Quigg et al., 2002; Pruss & Holtkamp, 2008), with moderate outcomes. Paraldehyde acts through a yet-unidentified mechanism, and appears to be relatively safe in terms of cardiovascular tolerability (Ramsay, 1989; Thulasimani & Ramaswamy, 2002), but because of the risk of crystal formation and its reactivity with plastic, it should be used only as fresh prepared solution in glass devices (Beyenburg et al., 2000). There are virtually no recent reports regarding its use in adults RSE, whereas rectal paraldehyde in children with status epilepticus resistant to benzodiazepines seems less efficacious than intravenous phenytoin (Chin et al., 2008). Etomidate is another anesthetic agent for which the exact mechanism of action is also unknown, which is also relatively favorable regarding cardiovascular side effects, and may be used for rapid sedation. Its use in RSE was reported in eight subjects (Yeoman et al., 1989). After a bolus of 0.3 mg/kg, a drip of up to 7.2 mg/kg/h for up to 12 days was administered, with hypotension occurring in five patients; two patients died. A reversible inhibition of cortisol synthesis represents an important concern, limiting its widespread use and implying a careful hormonal substitution during treatment (Beyenburg et al., 2000). Several nonsedating approaches have been reported. The use of lidocaine in RSE, a class Ib antiarrhythmic agent modulating sodium channels, was reviewed in 1997 (Walker & Slovis, 1997). Initial boluses up to 5 mg/kg and perfusions of up to 6 mg/kg/h have been mentioned; somewhat surprisingly, at times lidocaine seemed to be successful in controlling seizures in patients who were refractory to phenytoin. The aforementioned dosages should not be overshot, in order to keep lidocaine levels under 5 mg/L and avoid seizure induction (Hamano et al., 2006). A recent pediatric retrospective survey on 57 RSE episodes (37 patients) described a response in 36%, and no major adverse events; mortality was not given (Hamano et al., 2006 Verapamil, a calcium-channel blocker, also inhibits P-glycoprotein, a multidrug transporter that may diminish AED availability in the brain (Potschka et al., 2002). Few case reports on its use in humans are available; this medication nevertheless appears relatively safe (under cardiac monitoring) up to dosages of 360 mg/day (Iannetti et al., 2005). Magnesium, a widely used agent for seizures elicited by eclampsia, has also been anecdotally reported in RSE (Fisher et al., 1988; Robakis & Hirsch, 2006), but with scarce results even at serum levels of 14 mm. The rationale may be found in the physiologic blockage of NMDA channels by magnesium ions (Hope & Blumenfeld, 2005). Ketogenic diet has been prescribed for decades, mostly in children, to control refractory seizures. Its use in RSE as ''ultima ratio'' has been occasionally described: three of six children (Francois et al., 2003) and one adult (Bodenant et al., 2008) were responders. This approach displays its effect subacutely over several days to a few weeks. Because ''malignant RSE'' seems at times to be the consequence of immunologic processes (Holtkamp et al., 2005), a course of immunomodulatory treatment is often advocated in this setting, even in the absence of definite autoimmune etiologies (Robakis & Hirsch, 2006); steroids, adrenocorticotropic hormone (ACTH), plasma exchanges, or intravenous immunoglobulins may be used alone or in sequential combination. Nonpharmacologic Approaches These strategies are described somewhat less frequently than pharmacologic approaches. Acute implantation of vagus nerve stimulation (VNS) has been reported in RSE (Winston et al., 2001; Patwardhan et al., 2005; De Herdt et al., 2009). Stimulation was usually initiated in the operation room, and intensity progressively adapted over a few days up to 1.25 mA (with various regimens regarding the other parameters), allowing a subacute seizure control; one transitory episode of bradycardia/asystole has been described (De Herdt et al., 2009). Of course, pending identification of a definite seizure focus, resective surgery may also be considered in selected cases (Lhatoo & Alexopoulos, 2007). Low-frequency (0.5 Hz) transcranial magnetic stimulation (TMS) at 90% of the resting motor threshold has been reported to be successful for about 2 months in a patient with epilepsia partialis continua, but with a weaning effect afterward, implying the need for a repetitive use (Misawa et al., 2005). More recently, TMS was applied in a combination of a short ''priming'' high frequency (up to 100 Hz) and longer runs of low-frequency stimulations (1 Hz) at 90-100% of the motor threshold in seven other patients with simple-partial status, with mixed results (Rotenberg et al., 2009). Paradoxically at first glance, electroconvulsive treatment may be found in cases of extremely resistant RSE. A recent case report illustrates its use in an adult patient with convulsive status, with three sessions (three convulsions each) carried out over 3 days, resulting in a moderate recovery; the mechanism is believed to be related to modification of the synaptic release of neurotransmitters (Cline & Roos, 2007). Therapeutic hypothermia, which is increasingly used in postanoxic patients (Oddo et al., 2008), has been the object of a recent case series in RSE (Corry et al., 2008). Reduction of energy demand, excitatory neurotransmission, and neuroprotective effects may account for the putative mechanism of action. Four adult patients in RSE were cooled to 31_-34_C with an endovascular system for up to 90 h, and then passively rewarmed over 2-50 h. Seizures were controlled in two patients, one of whom died; also one of the other two patients in whom seizures continued subsequently deceased. Possible side effects are related to acid-base and electrolyte disturbances, and coagulation dysfunction including thrombosis, infectious risks, cardiac arrhythmia, and paralytic ileus (Corry et al., 2008; Cereda et al., 2009). Finally, anecdotic evidence suggests that cerebrospinal fluid (CSF)-air exchange may induce some transitory benefit in RSE (Kohrmann et al., 2006); although this approach was already in use in the middle of the twentieth century, the mechanism is unknown. Acknowledgment A wide spectrum of pharmacologic (sedating and nonsedating) and nonpharmacologic (surgical, or involving electrical stimulation) regimens might be applied to attempt RSE control. Their use should be considered only after refractoriness to AED or anesthetics displaying a higher level of evidence. Although it seems unlikely that these uncommon and scarcely studied strategies will influence the RSE outcome in a decisive way, some may be interesting in particular settings. However, because the main prognostic determinant in status epilepticus appears to be related to the underlying etiology rather than to the treatment approach (Rossetti et al., 2005, 2008), the safety issue should always represent a paramount concern for the prescribing physician. Conclusion The author confirms that he has read the Journal's position on issues involved in ethical publication and affirms that this paper is consistent with those guidelines.

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Data sheet produced by the Iowa Department of Natural Resources is about different times of animals, insects, snakes, birds, fish, butterflies, etc. that can be found in Iowa.

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Background/Purpose: Gouty arthritis (GA) is a chronic inflammatory disease. Targeting the inflammatory pathway through IL-1_ inhibition with canakinumab (CAN) may provide significant long-term benefits. CAN safety versus triamcinolone acetonide (TA) over initial 24 weeks (blinded study) for patients (pts) with history of frequent attacks (_3 in year before baseline) was reported earlier from core (_-RELIEVED [_-REL] and _-REL-II) and first extension (E1) studies1. Herein we present full 18-month long-term CAN safety data, including open-label second extension (E2) studies. Methods: GA pts completing _-REL E1 and _-REL-II E1 studies1 were enrolled in these 1-year, open-label, E2 studies. All pts entering E2, whether randomized to CAN or TA, received CAN 150 mg sc on demand upon new attack. Data are presented only for pts randomized to CAN, and are reported cumulatively, i.e. including corresponding data from previously reported core and E1 studies. Long-term safety outcomes and safety upon re-treatment are presented as incidence rate per 100 patient-years (pyr) of study participation for AEs and SAEs. Deaths are reported for all pts (randomized to CAN or TA). Selected predefined notable laboratory abnormalities are shown (neutrophils, platelets, liver and renal function tests). Long-term attack rate per year is also provided. Results: In total, 69/115 (60%) and 72/112 (64.3%) of the pts randomized to CAN in the two core studies entered the two E2 studies, of which 68 and 64 pts, respectively completed the E2 studies. The 2 study populations had differing baseline comorbidity and geographic origin. Lab data (not time adjusted) for neutropenia appears worse after retreatment in _-REL E2, and deterioration of creatinine clearance appears worse after retreatment (Table 1). The time-adjusted incidence rates for AEs were 302.4/100 pyr and 360/100 pyr, and for SAEs were 27.9/100 pyr and 13.9/100 pyr in _-REL E2 and _-REL-II E2 respectively (Table 1). The time-adjusted incidence rates of any AEs, infection AEs, any SAEs, and selected SAEs before and after re-treatment are presented in Table 1. Incidence rates for AEs and SAEs declined after re-treatment, with the exception of SAEs in _-REL-II E2, which increased from 2.9/100 pyr to 10.9/100 pyr (no infection SAEs after retreatment in _-REL-II E2, and other SAEs fit no special pattern). In the total safety population (N_454, core and all extensions), there were 4 deaths, 2 in the core studies previously reported1 and 2 during the _-REL E2 study (one patient in the CAN group died from pneumonia; one patient in the TA group who never received CAN died of pneumococcal sepsis). None of the deaths was suspected by investigators to be study drug related. The mean rates of new attacks per year on CAN were 1.21 and 1.18 in _-REL E2 and in _-REL-II E2. Conclusion: The clinical safety profile of CAN upon re-treatment was maintained long-term with no new infection concerns

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Roadside cross-drainage culverts have been found to impact vehicle accident injury levels. Designers have commonly used three safety treatments to protect errant drivers from culvert accidents. These treatments have included: culvert extension, guardrail installation and grating. In order to define which safety treatment is the most appropriate, benefit-cost analysis has used accident cost reduction to estimate societal gains earned by using any safety treatment. The purpose of this study was to estimate accident costs for a wide range of roadway and roadside characteristics so that designers can calculate benefit/cost ratios for culvert safety treatment options under any particular scenario. This study began with conducting a parametric study in order to find variables which have significant impact on accident cost changes. The study proceeded with highway scenario modeling which included scenarios with different values for combinations of roadway and roadside variables. These variables were chosen based upon findings from the parametric study and their values were assigned based upon highway classification. This study shows that the use of different culvert safety treatments should be flexible to roadway and roadside characteristics. It also shows that culvert extension and grating were the safety treatments found to produce the lowest accident costs for all highway scenarios modeled. Therefore, it is believed that the expanded adoption of culvert extension and culvert grates can improve overall highway safety.

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This Phase II project follows a previous project titled Strategies to Address Nighttime Crashes at Rural, Unsignalized Intersections. Based on the results of the previous study, the Iowa Highway Research Board (IHRB) indicated interest in pursuing further research to address the quality of lighting, rather than just the presence of light, with respect to safety. The research team supplemented the literature review from the previous study, specifically addressing lighting level in terms of measurement, the relationship between light levels and safety, and lamp durability and efficiency. The Center for Transportation Research and Education (CTRE) teamed with a national research leader in roadway lighting, Virginia Tech Transportation Institute (VTTI) to collect the data. An integral instrument to the data collection efforts was the creation of the Roadway Monitoring System (RMS). The RMS allowed the research team to collect lighting data and approach information for each rural intersection identified in the previous phase. After data cleanup, the final data set contained illuminance data for 101 lighted intersections (of 137 lighted intersections in the first study). Data analysis included a robust statistical analysis based on Bayesian techniques. Average illuminance, average glare, and average uniformity ratio values were used to classify quality of lighting at the intersections.

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The Iowa Department of Transportation (DOT) requested a road safety audit (RSA) of the US 59/IA 9 intersection in northwestern Iowa, just south of the Minnesota border, to assess intersection environmental issues and crash history and recommend appropriate mitigation to address the identified safety issues at the intersection. Although the number of crashes at the location has not been significantly higher than the statewide average for similar intersections, the severity of these crashes has been of concern. This RSA was unique in that it included intersection video observation and recorded traffic conflict data analysis, along with the daylight and nighttime field reviews. This report outlines the findings and recommendations of the RSA team for addressing the safety concerns at this intersection.

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Report on the Iowa Department of Public Safety for the year ended June 30, 2011

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The immunogenicity of influenza vaccine is suboptimal in lung transplant recipients. Use of a booster dose and vaccine delivery by the intradermal rather than intramuscular route may improve response. We prospectively evaluated the immunogenicity and safety of a 2-dose boosting strategy of influenza vaccine. Sixty lung transplant recipients received a standard intramuscular injection of the 2006-2007 inactivated influenza vaccine, followed 4 weeks later by an intradermal booster of the same vaccine. Immunogenicity was assessed by measurement of geometric mean titer of antibodies after both the intramuscular injection and the intradermal booster. Vaccine response was defined as 4-fold or higher increase of antibody titers to at least one vaccine antigen. Thirty-eight out of 60 patients (63%) had a response after intramuscular vaccination. Geometric mean titers increased for all three vaccine antigens following the first dose (p < 0.001). However, no significant increases in titer were observed after the booster dose for all three antigens. Among nonresponders, 3/22 (13.6%) additional patients responded after the intradermal booster (p = 0.14). The use of basiliximab was associated with a positive response (p = 0.024). After a single standard dose of influenza vaccine, a booster dose given by intradermal injection did not significantly improve vaccine immunogenicity in lung transplant recipients.

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In 2012, the Iowa legislature passed a bill for an act relating to school bus safety, including providing penalties for failure to obey school bus warning lamps and stop signal arms, providing for a school bus safety study and administrative remedies, and making an appropriation. The bill, referred to as Iowa Senate File (SF) 2218 or “Kadyn’s Law,” became effective March 16, 2012. A multiagency committee addressed three specific safety study elements of Kadyn’s Law as follows: * Use of cameras mounted on school buses to enhance the safety of children riding the buses and aid in enforcement of motor vehicle laws pertaining to stop-arm violations * Feasibility of requiring school children to be picked up and dropped off on the side of the road on which their home is located * Inclusion of school bus safety as a priority in driver training curriculum This report summarizes the findings for each of these topics.

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p-toluensulfonate doped polypyrrole ~PPy!, undergoes an electric-field induced reversible transition from an insulating state to a highly conductive one. The spatially average field can be as small as 200 V/cm, when the temperature of the sample is below 20 K. The applied electric field leads to a sharp jump in the value of the current to a value which is nearly five orders of magnitude higher than before. When the applied electric field is reduced to below a critical value, the system switches back to a low conductive state. The effect is reversible, symmetric in voltage, and reproducible for different samples. The switching is, we believe, an electronic glass melting transition and it is due to the disordered, highly charged granular nature of PPy.

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BACKGROUND AND PURPOSE: The major drug-metabolizing enzymes for the oxidation of oxycodone are CYP2D6 and CYP3A. A high interindividual variability in the activity of these enzymes because of genetic polymorphisms and/or drug-drug interactions is well established. The possible role of an active metabolite in the pharmacodynamics of oxycodone has been questioned and the importance of CYP3A-mediated effects on the pharmacokinetics and pharmacodynamics of oxycodone has been poorly explored. EXPERIMENTAL APPROACH: We conducted a randomized crossover (five arms) double-blind placebo-controlled study in 10 healthy volunteers genotyped for CYP2D6. Oral oxycodone (0.2 mg x kg(-1)) was given alone or after inhibition of CYP2D6 (with quinidine) and/or of CYP3A (with ketoconazole). Experimental pain (cold pressor test, electrical stimulation, thermode), pupil size, psychomotor effects and toxicity were assessed. KEY RESULTS: CYP2D6 activity was correlated with oxycodone experimental pain assessment. CYP2D6 ultra-rapid metabolizers experienced increased pharmacodynamic effects, whereas cold pressor test and pupil size were unchanged in CYP2D6 poor metabolizers, relative to extensive metabolizers. CYP2D6 blockade reduced subjective pain threshold (SPT) for oxycodone by 30% and the response was similar to placebo. CYP3A4 blockade had a major effect on all pharmacodynamic assessments and SPT increased by 15%. Oxymorphone C(max) was correlated with SPT assessment (rho(S)= 0.7) and the only independent positive predictor of SPT. Side-effects were observed after CYP3A4 blockade and/or in CYP2D6 ultra-rapid metabolizers. CONCLUSIONS AND IMPLICATIONS: The modulation of CYP2D6 and CYP3A activities had clear effects on oxycodone pharmacodynamics and these effects were dependent on CYP2D6 genetic polymorphism.