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91.
Objective: Relationship maintenance strategies help to ensure the continuation of valued relationships by keeping them at a certain level of intimacy. This study evaluated how lung cancer patients' and spouses' efforts to maintain their relationships affected their psychological and marital adjustment over time. Design: Psychosocial questionnaires were administered within 1 month of lung cancer treatment initiation (baseline) and 3 and 6 months later to 158 lung cancer patients and their spouses. Main Outcome Measures: Study outcomes were global severity index scores on the Brief Symptom Inventory, and total scores on the Dyadic Adjustment Scale. Results: Multilevel modeling analyses using the Actor-Partner Interdependence Model showed that, regardless of gender or social role (i.e., patient or spouse), individuals who engaged in the strategies of positivity, networks, and shared tasks reported less distress at baseline than other participants. Over time, the effects of providing more assurances and experiencing a partner's increased reliance on social networks differed: patient distress was exacerbated, and spouse distress was alleviated. Couples where both partners engaged in more frequent maintenance behaviors reported greater dyadic adjustment at baseline and over time. Conclusion: For couples coping with lung cancer, the initial treatment period may be an important time that sets the tone for future spousal interactions. Engaging in relationship maintenance during this stressful time may help mold more resilient relationships and facilitate adjustment as the disease progresses. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
S Pedersen SF Pedersen B Nilius IH Lambert EK Hoffmann 《Canadian Metallurgical Quarterly》1999,1416(1-2):271-284
The supernatant from a suspension of Ehrlich cells exposed to centrifugation at 700xg for 45 s induced a transient increase in the intracellular concentration of free, cytosolic Ca2+, [Ca2+]i, as well as activation of an outwardly rectifying whole-cell current when added to a suspension of non-stimulated cells. These effects were inhibited by suramin, a non-specific P2 receptor antagonist, and mimicked by ATP. Reversed phase HPLC analysis revealed that the supernatant from Ehrlich cells exposed to centrifugation contained 2. 6+/-0.2 microM ATP, and that the mechanical stress-induced release of ATP was inhibited by glibenclamide and verapamil, non-specific inhibitors of the cystic fibrosis transmembrane conductance regulator and P-glycoprotein, respectively. After trypan blue staining, less than 0.5% of the cells were unable to extrude the dye. Addition of extracellular ATP induced a suramin-sensitive, transient, concentration-dependent increase in [Ca2+]i, activation of an outwardly rectifying whole-cell current and a hyperpolarization of the plasma membrane. The ATP-induced hyperpolarization of the plasma membrane was strongly inhibited in the presence of charybdotoxin (ChTX), an inhibitor of several Ca2+-activated K+ channels, suggesting that stimulation of P2 receptors in Ehrlich cells evokes a Ca2+-activated K+ current. The relative potencies of several nucleotides (ATP, UTP, ADP, 2-MeSATP, alpha,beta-MeATP, bzATP) in eliciting an increase in [Ca2+]i, as well as the effect of repetitive addition of nucleotides were investigated. The results lead us to conclude that mechanical stimulation of Ehrlich cells leads to release of ATP, which in turn stimulates both P2Y1 and P2Y2 receptors, resulting in Ca2+ influx as well as release and activation of an outwardly rectifying whole-cell current. 相似文献
93.
This article presents an efficient meta-heuristic method for reconfiguration of distribution systems. A modified Tabu Search (MTS) algorithm is used to reconfigure distribution systems so that active power losses are globally minimized with turning on/off sectionalizing switches. TS algorithm is introduced with some modifications such as using a tabu list with variable size according to the system size. Also, a random multiplicative move is used in the search process to diversify the search toward unexplored regions. The Kirchhoff algebraic method is adopted to check the radial topology of the system. A salient feature of the MTS method is that it can quickly provide a global optimal or near-optimal solution to the network reconfiguration problem. To verify the effectiveness of the proposed approach, the effect of load variation is taken into consideration and comparative studies are conducted on three test systems with rather encouraging results. The obtained results, using the proposed MTS approach, are compared with that obtained using other approaches in the previous work. 相似文献
94.
Eduard Emil Iojoiu Badr Bassou Nolven Guilhaume David Farrusseng Arnold Desmartin-Chomel Karine Lombaert Daniel Bianchi Claude Mirodatos 《Catalysis Today》2008,137(1):103
A methodology for the evaluation of diesel soot oxidation catalysts by high-throughput (HT) screening was developed. The optimal experimental conditions (soot amount, catalyst/soot ratio, type of contact, composition and flow rate of gas reactants) ensuring a reliable and reproducible detection of light-off temperatures in a 16 parallel channels reactor were set up. The temperature profile measured in the catalyst/soot bed under TPO conditions when the exothermic combustion of soot takes place was shown to provide an accurate measurement of the ignition. Its reproducibility and relevance were checked. The results obtained with a reference noble metal free catalyst (La0.8Cr0.8Li0.2O3 perovskite) agree very well with literature data. Qualitative mechanistic features could be derived from these experiments, stressing the likely limiting step of oxygen transfer from catalyst surface to soot particulates to ignite the soot combustion. Ceria material was shown to be more appropriate than perovskite one. From an HT screening of a large diverse library (over 100 mixed oxides catalysts) under optimized conditions, about 10 new formulations were found to perform better than selected noble metal free reference materials. 相似文献
95.
Mahasen S. Amine Amal A. Mahmoud Samy K. Badr Alaa S. Gouda 《Journal of surfactants and detergents》2012,15(2):179-190
The titled compounds were prepared from 2-amino-5-heptadecyl[1,3,4]thiadiazole (1). Diazotization of (1) produced (2) which was coupled with active methylene compounds and gave azo ⇌ hydrazono derivatives (3A, 3B)
a–d
. It was found that there is regio-specificity for addition of different nucleophiles to these tautomers; thus, nitrogen nucleophiles
such as hydrazine hydrate, hydroxylamine hydrochloride and thiourea were reacted via Azo tautomer (3A) to yield pyrazole, isoxazole and pyrimidine respectively (5-7), while carbon nucleophiles as phenylisocyanate was reacted via the hydrazono tautomer (3B) and produced triazine derivatives (4). Additionally, the diazonium chloride (2) was coupled with alkaline 2-naphthol and produced 2-(5-heptadecyl-[1,3,4]thiadiazol-2-yl)-1,2-dihydro-3-oxa-1,2-diaza-cyclopenta[a]naphthalene
(8). UV–visible spectra of the synthesized colored compounds (2-8) showed λ max at 374–398 nm, while screening these compounds in vitro against micro-organisms (including structure-activity relationship
SAR study) revealed high antibacterial and moderate antifungal activities. Propoxylation of compounds 1, 3, 5, 6, 7 and 8 with 3, 5, 7 mol of propylene oxide produced nonionic surfactants I(a–c)–IX(a–c) having surface active properties so, it is clear that the tested surfactants can be used in the manufacture of dyes, drugs,
cosmetics, emulsifiers, pesticides, luminphores for optical applications and many other industries with low toxicity to human
beings and the environment owing to their high solubility and good biodegradability. 相似文献
96.
Badr M. Abou-Zeid Wael W. El-Dakhakhni A. Ghani Razaqpur S. Foo 《Canadian Metallurgical Quarterly》2011,25(5):411-421
This paper presents the results of an analytical investigation of one-way unreinforced masonry (URM) walls retrofitted with externally anchored steel studs and subjected to blast loads. Using the wall geometrical and material properties, deflected shape, and crack pattern as input, a nonlinear model is developed to predict the inward force-displacement relationship of the retrofitted walls. In addition, using a rigid body analysis, a simple bilinear force-displacement relationship is developed to model the outward force-displacement relationship of the walls. Utilizing these two force-displacement relationships (resistance functions), a generalized single-degree-of-freedom (SDOF) model is developed to capture the nonlinear out-of-plane dynamic response of the retrofitted walls under blast loads. The SDOF model captured the experimentally observed displacement responses of the tested walls with reasonable accuracy. The model was also used to investigate the influence of block thickness, wall slenderness ratio, blast load intensity, and blast pulse shape on the out-of-plane dynamic response of retrofitted walls. The results demonstrated that anchored steel-stud systems could significantly enhance the out-of-plane capacity of the retrofitted walls by increasing their out-of-plane capacity and reducing their displacement. 相似文献
97.
Badr M. Abou-Zeid Wael W. El-Dakhakhni A. Ghani Razaqpur S. Foo 《Canadian Metallurgical Quarterly》2011,25(5):441-453
Six full-scale concrete masonry walls were tested under free-field blast loading using different charge sizes up to 250?kg of ammonium nitrate/fuel oil (ANFO) and at a constant stand-off distance of 15.0?m to cover a wide range of expected damage levels. Five walls were retrofitted with cold-formed steel studs anchored to the wall backs and were compared to the remaining as-built wall. Significant enhancement to the out-of-plane blast resistance of the retrofitted walls, compared to the as-built wall, was observed. This enhancement is attributed to the development of a tied-arch action in the retrofitted walls in which the masonry forms a compression strut while the steel studs serve as the tie. A simplified single-degree-of-freedom model was used to analyze the experimental results, and the model results agreed well with the observed damage levels and the resistances of the walls. In addition, the effectiveness of the proposed retrofit technique was evaluated in terms of strength enhancement and wall deflection reduction. The test results were also compared with those predicted by available blast damage assessment models for unreinforced masonry walls. However, it was found that available models, which do not account for the tied-arch mechanism, greatly underestimate the actual blast capacity of the retrofitted walls because of the assumption of a tensile flexural failure mode. Additionally, the proposed retrofit technique shifts the mode of failure from flexure to shear. 相似文献
98.
The characterizations of virgin and scrapped polyethylene samples (VPE and SPE) and VPE/SPE blends were studied using different analytical techniques. The obtained data regarding crosslink density demonstrated that the radiation‐induced crosslinking of VPE, SPE, and VPE/SPE samples increased as a result of increasing irradiation dose, blending VPE with SPE, and loading the VPE/SPE blend with trimethylol propane triacrylate (TMPTA). The use of differential scanning calorimetry technique was aimed at revealing the effect of sample composition (VPE, SPE, and VPE/SPE) and also the effect and type of irradiation on the melting temperature (Tm) and the heat of transformation (ΔHf). The melting temperature and heat of transformation increased with increasing either irradiation dose or loading the polymeric samples with TMPTA. In addition, the application of thermogravimetric analysis (TGA) was used to study the degradation characteristics of the polymeric samples in terms of onset temperature (Ti), temperature at maximum weight loss (Ts), and activation energy (Ea). The TGA results showed that the irradiation (EB and γ‐rays) and loading of polymeric samples with TMPTA led to a thermally stable polymeric matrix with higher Ti, Ts, and Ea values. The blank SPE sample or those blend rich in SPE matrix were highly thermally stable than that blank VPE one. The X‐ray diffraction investigation illustrated that VPE samples undergoes phase transformation between orthorhombic, monomclinic, and/or hexagonal as a result of irradiation. POLYM. COMPOS. 27:709–717, 2006. © 2006 Society of Plastics Engineers 相似文献
99.
Reham Hammad Reda Badr Aglan Shaymaa A. Mohammed Eman Abu-elnasr Awad Marwa A. Elsaid Hanan M. Bedair Seham K. Khirala Mohamed A Selim Asmaa A. Abo Elqasem Areej Rushdi Mohamed Ali Omaima I. Abo-Elkheir Eman F. Sanad Nadia M. Hamdy 《International journal of molecular sciences》2022,23(20)
Virus-related hepatocellular carcinoma (HCC) pathogenesis involves liver inflammation, therefore, despite successful treatment, hepatitis C virus (HCV) may progress to HCC from initiated liver cirrhosis. Cytotoxic T cells (Tcs) are known to be involved in HCV-related cirrhotic complications and HCC pathogenesis. The inhibitory checkpoint leukocyte-associated immunoglobulin-like receptor-1 (LAIR-1) is expressed on Tcs. Therefore, we aimed to determine whether the Tc expression level of LAIR-1 is associated with HCC progression and to evaluate LAIR-1 expression as a noninvasive biomarker for HCC progression in the context of liver cirrhosis related to HCV genotype 4 (G4) in Egyptian patients’ peripheral venous blood liquid biopsy. A total of 64 patients with HCC and 37 patients with liver cirrhosis were enrolled in this case-controlled study, and their LAIR-1 expression on Tc related to the progression of liver cirrhosis was examined and compared to that of the apparently healthy control group (n = 20). LAIR-1 expression was analyzed using flow cytometry. Results: The HCC group had significantly higher LAIR-1 expression on Tc and percentage of Tc positive for LAIR-1 (LAIR-1+Tc%) than the HCV G4-related liver cirrhosis group. LAIR-1+Tc% was correlated with the HCC surrogate tumor marker AFP (r = 0.367, p = 0.001) and insulin resistance and inflammation prognostic ratios/indices. A receiver operating characteristic (ROC) curve revealed that adding LAIR-1+Tc% to AFP can distinguish HCC transformation in the Egyptian patients’ cohort. Upregulated LAIR-1 expression on Tc could be a potential screening noninvasive molecular marker for chronic inflammatory HCV G4 related liver cirrhosis. Moreover, LAIR-1 expression on Tc may be one of the players involved in the progression of liver cirrhosis to HCC. 相似文献
100.
Wassim Fassi Fihri Hassan El Ghazi Badr Abou El Majd Faissal El Bouanani 《International Journal of Communication Systems》2019,32(15)
Cognitive radio network (CRN) is a promising technology, which enables secondary users to use the free spectrum channels without causing detrimental interference with the primary user (PU). Nevertheless, CRN is subject to numerous cyber attacks that have a negative impact on its performance. Among the CRN attacks, the primary user emulation (PUE) attack is known to be one of the malicious attacks threatening CRN security. Several attacks detection techniques, based on attacker localization, have been investigated in the literature. These techniques include the trilateration, received signal strength indication (RSSI), and network coding approach as well. However, most of these techniques do not consider the uncertainty related to CRN, which can be modeled by a cost function defined as a weighted sum of conditional probabilities. In this paper, a localization technique, relied on a trilateration computation and a Bayesian model, is proposed for PUE position detection purpose under uncertainty conditions assumption. Particularly, the estimation of PUE position is performed through trilateration method based on RSSI at the anchor nodes for the signal coming from either PU or PUE, whereas, the Bayesian decision model, based on a cost function, is involved to check the PU legitimacy. The simulation results show that the decision‐making approach "Security, productivity, Balancing" influences directly the zone of the PUE attack detection. 相似文献