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81.
CO2 utilization in upsteam oil and gas applications requires CO2-soluble additives such as polymers, surfactants, and other components. Here we report the facile synthesis of CO2-soluble oxidizers composed of judiciously selected organic cations paired with oxidizing anions. [Bu4N]BrO3 and [Bu4N]ClO3 are prepared using a double displacement synthetic strategy, whereby the crystalline product is readily obtained in high yield and structurally characterized using single-crystal X-ray diffraction. The facility of the approach is demonstrated through the preparation of several additional alkylammonium bromate compounds. Static solubility studies using a high-pressure cell with viewing windows showed that tetrabutylammonium compounds could be solubilized using cosolvent-modified CO2. Using 4 mol% ethanol as cosolvent, >3 mM [Bu4N]BrO3 could be dissolved in CO2, while ∼0.75 mM [Bu4N]ClO3 could be dissolved in the same solvent system. The solubility properties of [Bu4N]BrO3 along with its thermal stability up to ∼200 °C suggest that it is a promising oilfield oxidizer that can be utilized in subterranean CO2 applications.

Bromate and chlorate salts were hydrophobically modified with tetrabutylammonium to yield oxidizers that are soluble in CO2-cosolvent mixtures.  相似文献   
82.
83.
Journal of Autism and Developmental Disorders - Camouflaging refers to strategies used by autistic people to mask or hide social difficulties. The current study draws on Social Identity Theory to...  相似文献   
84.
Tumor necrosis factor-alpha (TNF-alpha) decreased the expression of pulmonary surfactant proteins SP-A and SP-B in human pulmonary adenocarcinoma cell lines. The effect of TNF alpha on SP-A content and mRNA in the pulmonary adenocarcinoma cell line, H441-4, was concentration and time dependent. TNF alpha decreased the cellular content of SP-A to less than 10% of control 48 h after addition. TNF alpha decreased de novo synthesis of SP-A and decreased the accumulation of SP-A in media. SP-A mRNA was decreased within 12 h of addition of TNF alpha, with nearly complete loss of SP-A mRNA observed after 24 h. Inhibitory effects of TNF alpha on SP-A mRNA were dose-related with nearly complete inhibition of SP-A mRNA caused by 25 ng/ml TNF alpha. The effects of TNF alpha on SP-A were distinct from the effects of interferon gamma which increased SP-A content approximately twofold in H441-4 cells. TNF alpha also decreased the content of SP-B mRNA. In contrast to the inhibitory effect of TNF alpha on SP-A and SP-B mRNA, TNF alpha increased mRNA encoding human manganese superoxide dismutase (Mn-SOD). TNF alpha did not inhibit growth, alter cell viability or beta-actin mRNA in either cell line. These in vitro studies demonstrate the marked pretranslational inhibitory effects of the cytokine, TNF alpha, on the expression of pulmonary surfactant proteins, SP-A and SP-B. The results support the concept that macrophage-derived cytokines may control surfactant protein expression.  相似文献   
85.

Background

The nontechnical and team skills of surgical teams are critical for safety and efficiency in the operating room. Assessment of nontechnical and team skills can facilitate improvement by encouraging both self-reflection and team reflection, identifying training needs, and informing operating room (OR) team training approaches. The observational teamwork assessment for surgery (OTAS) tool is a well-validated and robust tool for capturing teamwork in the operating room. The aims of the present study were to systematically adapt and refine the OTAS for German-speaking OR staff and to test the adapted assessment tool (OTAS-D) for psychometric properties and metric equivalence.

Methods

The study was carried out in three stages: at stage 1, OTAS was translated into German. At stage 2, experienced German OR experts (surgeons, OR nurses, anesthetists) were interviewed. At stage 3, two blinded assessors observed 11 general surgical operations (general surgical and vascular procedures) and interrater reliability was tested for refined OTAS-D behavioral exemplars and scorings.

Results

The German OR experts confirmed the applicability and content validity of the vast majority of translated behavioral exemplars. After their evaluation, 32 items were changed slightly, six were changed substantially, and one item was added. During observations, perfect and substantial interobserver agreement was found for 77 behavioral exemplars (67.1 % of the items, kappa coefficient >0.60). Rating at all OTAS behaviors showed acceptable levels of reliability (intraclass correlation coefficients >0.72).

Conclusions

The OTAS-D is a tool for valid and reliable assessment of nontechnical skills that contribute to safe and effective surgical performance in ORs staffed by German-speaking professionals. Furthermore, our study serves as an example for systematically adapting and customizing well-established observational tools across different healthcare environments.  相似文献   
86.
87.
Using data from the Simons Simplex Collection, the present study examined the impact of child externalizing behavior and parental broad autism phenotype traits on substance use among parents of children with autism spectrum disorder (n = 2,388). For both fathers and mothers, child externalizing behaviors predicted tobacco use (OR = 1.01 and OR = 1.02, respectively), whereas rigidity increased risk of tobacco use for fathers (OR = 1.29) but not mothers. Additionally, among mothers, child externalizing behaviors increased risk of illegal substance use (OR = 1.04), whereas maternal rigidity decreased risk of alcohol use (OR = .83). Collectively, results suggest that child externalizing behaviors and parental rigidity may have differing impacts on the types of substances used by parents.  相似文献   
88.
89.
The role of dopaminergic terminals in the medial preoptic area (MPO) in the regulation of male rat copulatory behavior was investigated. A 6-hydroxydopamine (6-OHDA) injection into the MPO of animals pretreated with desipramine resulted in a small (23%) depletion of DA, and no impairment of copulatory activity. Further depletion of catecholamines with alpha-methyl p-tyrosine (AMPT) produced several deficits in the copulatory behavior of 6-OHDA-treated males, at a dose of AMPT that did not adversely affect copulation prior to 6-OHDA administration. The dose-related effects of intracranial apomorphine (APO) injections were also altered by 6-OHDA injections into the MPO. The inhibition previously found with 0.2 microgram of APO into the lateral ventricle of normal males was abolished by 6-OHDA treatment. A facilitation of copulatory behavior was observed following the injection of 0.2 microgram of APO into the MPO of 6-OHDA-treated animals, whereas this treatment did not affect the copulatory behavior of intact animals. Finally, inhibitory effects observed following an injection of 0.1 microgram of APO into the MPO of normal males were blocked by 6-OHDA administration. The relative roles of presynaptic autoreceptors and postsynaptic DA receptors in the MPO in mediating the dose-related effects of APO on copulatory behavior are discussed.  相似文献   
90.
Aims/hypothesis  Supraphysiological levels of the amyloidogenic peptide human islet amyloid polypeptide have been associated with beta cell endoplasmic reticulum (ER) stress. However, in human type 2 diabetes, levels of human IAPP are equivalent or decreased relative to matched controls. Thus, we sought to investigate whether ER stress is induced during amyloidogenesis at physiological levels of human IAPP. Methods  Islets from human IAPP transgenic mice that develop amyloid, and non-transgenic mice that do not, were cultured for up to 7 days in 11.1, 16.7 and 33.3 mmol/l glucose. Pancreases from human IAPP transgenic and non-transgenic mice and humans with or without type 2 diabetes were also evaluated. Amyloid formation was determined histologically. ER stress was determined in islets by quantifying mRNA levels of Bip, Atf4 and Chop (also known as Ddit3) and alternate splicing of Xbp1 mRNA, or in pancreases by immunostaining for immunoglobulin heavy chain-binding protein (BIP), C/EBP homologous protein (CHOP) and X-box binding protein 1 (XBP1). Results  Amyloid formation in human IAPP transgenic islets was associated with reduced beta cell area in a glucose- and time-dependent manner. However, amyloid formation was not associated with significant increases in expression of ER stress markers under any culture condition. Thapsigargin treatment, a positive control, did result in significant ER stress. Amyloid formation in vivo in pancreas samples from human IAPP transgenic mice or humans was not associated with upregulation of ER stress markers. Conclusions/interpretation  Our data suggest that ER stress is not an obligatory pathway mediating the toxic effects of amyloid formation at physiological levels of human IAPP.  相似文献   
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