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41.
Limited research has focused on the effect of high temperatures on the textile-reinforced mortar (TRM)-to-masonry bond. In this study, masonry prisms that were furnished with double-layered TRM strips were tested under shear bond conditions after their exposure to 200 °C and 400 °C for 1 h using the single-lap/single-prism setup. A total of four TRM systems were applied sharing the same type of textile –a dry AR glass fiber one– and different matrices: two cementitious matrices, namely a normal-weight (TRCNM) and a lightweight (TRCLM) one, and two counterpart alkali-activated matrices (TRAANM and TRAALM) based on metakaolin and fly ash. Specimens’ exposure to elevated temperatures did not alter their failure mode which was due to the sleeve fibers’ rupture along with core fibers’ slippage from the mortar. The residual bond capacity of the TRM systems decreases almost linearly with increasing exposure temperature. The alkali-activated textile reinforced mortars outperformed their cement-based counterparts in terms of bond strength at every temperature. All systems retained close to 50% of their original shear bond strength after heating at 400 °C. Per the type of binder, lightweight matrices resulted in either comparable (cement-based systems) or better (alkali-activated systems) heat protection at the TRM/masonry interface. 相似文献
42.
Paraskevi Mavrogiorgou Theresa Thomaßen Frederike Pott Vera Flasbeck Holmer Steinfath Georg Juckel 《European psychiatry》2022,65(1)
BackgroundThe experience of time, or the temporal order of external and internal events, is essential for humans. In psychiatric disorders such as depression and schizophrenia, impairment of time processing has been discussed for a long time.AimsIn this explorative pilot study, therefore, the subjective time feeling as well as objective time perception were determined in patients with depression and schizophrenia, along with possible neurobiological correlates.MethodsDepressed (n = 34; 32.4 ± 9.8 years; 21 men) and schizophrenic patients (n = 31; 35.1 ± 10.7 years; 22 men) and healthy subjects (n = 33; 32.8 ± 14.3 years; 16 men) were tested using time feeling questionnaires, time perception tasks and critical flicker-fusion frequency (CFF) and loudness dependence of auditory evoked potentials (LDAEP) to determine serotonergic neurotransmission.ResultsThere were significant differences between the three groups regarding time feeling and also in time perception tasks (estimation of given time duration) and CFF (the “DOWN” condition). Regarding the LDAEP, patients with schizophrenia showed a significant negative correlation to time experience in terms of a pathologically increased serotonergic neurotransmission with disturbed time feeling.ConclusionsImpairment of time experience seems to play an important role in depression and schizophrenia, both subjectively and objectively, and novel neurobiological correlates have been uncovered. It is suggested, therefore, that alteration of experience of time should be increasingly included in the current psychopathological findings. 相似文献
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44.
Theofilou P 《International urology and nephrology》2012,44(1):245-253
Background and objective
Patients’ beliefs regarding their health are important to understand responses to chronic disease. The present study aimed to determine (i) whether beliefs about health differ between different renal replacement therapies in end-stage renal disease (ESRD) patients and (ii) whether these beliefs are associated with health-related quality of life (HQoL), as well as with mental health. 相似文献45.
MC Conry N Humphries K Morgan Y McGowan A Montgomery K Vedhara E Panagopoulou H McGee 《BMC health services research》2012,12(1):275
ABSTRACT: BACKGROUND: Against a backdrop of rising healthcare costs, variability in care provision and an increased emphasis on patient satisfaction, the need for effective interventions to improve quality of care has come to the fore. This is the first ten year (2000--2010) systematic review of interventions which sought to improve quality of care in a hospital setting. This review moves beyond a broad assessment of outcome significance levels and makes recommendations for future effective and accessible interventions. METHODS: Two researchers independently screened a total of 13,195 English language articles from the databases PsychInfo, Medline, PubMed, EmBase and CinNahl. There were 120 potentially relevant full text articles examined and 20 of those articles met the inclusion criteria. RESULTS: Included studies were heterogeneous in terms of approach and scientific rigour and varied in scope from small scale improvements for specific patient groups to large scale quality improvement programmes across multiple settings. Interventions were broadly categorised as either technical (n = 11) or interpersonal (n = 9). Technical interventions were in the main implemented by physicians and concentrated on improving care for patients with heart disease or pneumonia. Interpersonal interventions focused on patient satisfaction and tended to be implemented by nursing staff. Technical interventions had a tendency to achieve more substantial improvements in quality of care. CONCLUSIONS: The rigorous application of inclusion criteria to studies established that despite the very large volume of literature on quality of care improvements, there is a paucity of hospital interventions with a theoretically based design or implementation. The screening process established that intervention studies to date have largely failed to identify their position along the quality of care spectrum. It is suggested that this lack of theoretical grounding may partly explain the minimal transfer of health research to date into policy. It is recommended that future interventions are established within a theoretical framework and that selected quality of care outcomes are assessed using this framework. Future interventions to improve quality of care will be most effective when they use a collaborative approach, involve multidisciplinary teams, utilise available resources, involve physicians and recognise the unique requirements of each patient group. 相似文献
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47.
Sotiris Plainis Paraskevi Tzatzala Yiannis Orphanos Miltiadis K Tsilimbaris 《Optometry and vision science》2007,84(7):647-653
PURPOSE: The log MAR visual acuity (VA) chart developed for use in the Early Treatment Diabetic Retinopathy Study (ETDRS) is composed of 10 Sloan letters, which are not used in the Greek, Cyrillic, and Central European alphabets. In this study we evaluate a modified ETDRS chart, the University of Crete (UoC) chart, which contains a set of letters readable by all European citizens. METHODS: In the UoC charts, the letters C, D, R, N, V, S, and Z were substituted with E, P, B, X, Y, A, and T, respectively. The similarity between the modified and the standard acuity charts was evaluated using two procedures. First, VA of 227 secondary school children (454 eyes) was evaluated using both sets of charts. Second, the relative difficulty for the identification of individual Sloan letters used in both charts, as well as letter M, was assessed from psychometric functions for five subjects. RESULTS: Bland-Altman plots revealed no statistical significant differences in the value of VA between the standard and the UoC set of charts. Although, estimates of identification log MAR threshold showed relatively significant interletter variability, in total, the new set of Sloan letters was equally identifiable with the original set. CONCLUSIONS: The overall pattern of results suggests that the modified log MAR UoC charts forms a valid alternative to the ETDRS for assessing VA in multinational clinical trials, offering the advantage of containing letters recognizable by a wider population basis, such as European citizens, as well as subjects from countries using the Cyrillic alphabet. 相似文献
48.
Vagiakou-Voudris E Mylona-Petropoulou D Kalogeropoulou E Chantzis A Chini S Tsiodra P Malamou-Lada E 《Scandinavian journal of infectious diseases》2002,34(10):766-767
Leuconostoc species, which are members of the family Streptococcacae, have only recently been recognized as potential pathogens. We describe a patient with type II diabetes mellitus who had multiple liver abscesses associated with bacteremia due to Leuconostoc lactis. To our knowledge, this is the first case of this association to be reported in the literature. 相似文献
49.
Enhanced microtubule-dependent trafficking and p53 nuclear accumulation by suppression of microtubule dynamics 下载免费PDF全文
Giannakakou P Nakano M Nicolaou KC O'Brate A Yu J Blagosklonny MV Greber UF Fojo T 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(16):10855-10860
The tumor suppressor protein p53 localizes to microtubules (MT) and, in response to DNA damage, is transported to the nucleus via the MT minus-end-directed motor protein dynein. Dynein is also responsible for MT-mediated nuclear targeting of adenovirus type 2 (Ad2). Here we show that treatment with low concentrations of MT-targeting compounds (MTCs) that do not disrupt the MT network but are known to suppress MT dynamics enhanced p53 nuclear accumulation, and the activation of the p53-downstream target genes. p53 nuclear accumulation required binding of MTCs to MTs and enhanced the induction of p53-up-regulated modulator of apoptosis (PUMA) mRNA and apoptosis on challenging cells with the DNA-damaging drug adriamycin. Low concentrations of MTCs enhanced the rate of movement of fluorescent Ad2 to the nucleus and increased the nuclear targeting efficiency of Ad2. We propose that suppression of MT dynamics by low concentrations of MTCs enhances MT-dependent trafficking toward the minus ends of MTs and facilitates nuclear targeting. 相似文献
50.
Xekouki P Fryssira H Maniati-Christidi M Amenta S Karavitakis EM Kanaka-Gantenbein C Dacou-Voutetakis C 《Journal of pediatric endocrinology & metabolism : JPEM》2005,18(2):205-207
Pre- and postnatal growth retardation of unknown pathogenesis is a common clinical feature in patients with Williams-Beuren syndrome (WBS). However, growth hormone deficiency (GHD) has not been considered a major cause of growth retardation. There is only one patient in the literature with confirmed GHD who responded well to human growth hormone (hGH) therapy. We report a female infant with confirmed WBS who, through provocative testing, was found to have GHD and who responded satisfactorily to hGH therapy. Height SDS was -4.2 at the age of 12 months when hGH was initiated and increased to -0.8 at the age of 4.25 years. The pathogenesis of GHD in our patient is unclear. Nevertheless, the elevated levels of prolactin and the response of hGH to growth hormone releasing hormone (GHRH) administration are indicative of a hypothalamic rather than pituitary defect. In conclusion, GH deficiency might contribute to the growth failure in a number of patients with WBS and in such cases hGH therapy will most likely improve final height. 相似文献