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1.
Red sweet peppers held in cold storage were periodically sampled at 1-week intervals over a 3-weeks period using three-point bending, puncture, cutting, and Volodkevich (coupled with acoustic emission) tests, confocal laser scanning microscopy (CLSM) and other physicochemical measurements. At each sampling, tissue specimens were soaked in mannitol solutions (0.0–0.9M) and puncture test, dimension changes and CLSM were used to identify degrees of turgidity present in osmotically manipulated pepper tissue. Pepper texture became crumbly with increased storage time due to softening and wilting processes. The Young's modulus, derived from the bending test using the single-edge notched bend geometry without notches decreased progressively during cold storage and resulted as the best mechanical parameter for measuring the loss of whole-tissue stiffness by both decreased cell wall stiffness and turgor pressure. Osmotic adjustment indicated that the pepper structure is extremely anisotropic, with the specimen's “average” relative thickness (RT) being the dimension change more affected. Incipient plasmolysis was evident in the highest mannitol concentration (0.9M), therefore, the turgor pressure of nonsoaked tissue could not be inferred. However, significant correlations were found between RT and puncture parameters such as initial slope, initial and final distances, and the number of flesh and skin force peaks, which depended on the dilation or shrinkage caused by the osmotic adjustment. During storage, soaked tissues had lower crunchy texture than nonsoaked, reflecting that cell wall stiffness plays a more significant role in determining pepper crunchiness than cell turgor pressure.  相似文献   
2.
Chickpea flour (CF)‐based muffin formulations were made with CF alone and with added biopolymers [whey protein (WP), xanthan gum (XG) and inulin (INL)] to evaluate their suitability to be a wheat flour (WF) substitute in muffins. Structural characteristics of the batters and muffins were studied by means of rheometry, microscopy, physicochemical properties, and texture and sensory analysis. Partial replacement of CF with XG, alone (at 0.5 and 1%) or blended with either WP or INL, significantly increased the batter viscoelasticity as denser matrices developed; moreover, the muffins with XG added at 1% had similar hardness to wheat gluten muffins. The replacement of WF decreased the springiness, cohesiveness, chewiness, resilience and specific volume of the muffin. However, baked muffins with added XG also showed higher sensory sponginess and moisture associated with numerous air bubbles in the batter and were perceived to be easier to swallow and to have better general appearance.  相似文献   
3.
Cerebellar ataxias (CA) comprise a heterogeneous group of neurodegenerative diseases characterized by a lack of motor coordination. They are caused by disturbances in the cerebellum and its associated circuitries, so the major therapeutic goal is to correct cerebellar dysfunction. Neurotrophic factors enhance the survival and differentiation of selected types of neurons. Liver growth factor (LGF) is a hepatic mitogen that shows biological activity in neuroregenerative therapies. We investigate the potential therapeutic activity of LGF in the 3-acetylpiridine (3-AP) rat model of CA. This model of CA consists in the lesion of the inferior olive-induced by 3-AP (40 mg/kg). Ataxic rats were treated with 5 µg/rat LGF or vehicle during 3 weeks, analyzing: (a) motor coordination by using the rota-rod test; and (b) the immunohistochemical and biochemical evolution of several parameters related with the olivo-cerebellar function. Motor coordination improved in 3-AP-lesioned rats that received LGF treatment. LGF up-regulated NeuN and Bcl-2 protein levels in the brainstem, and increased calbindin expression and the number of neurons receiving calbindin-positive projections in the cerebellum. LGF also reduced extracellular glutamate and GABA concentrations and microglia activation in the cerebellum. In view of these results, we propose LGF as a potential therapeutic agent in cerebellar ataxias.  相似文献   
4.
Cladding creep rupture is thought to be the most likely and limiting failure mechanism of spent fuel in dry storage. In spite of being highly unlikely, the current trend towards high burnups is drawing further attention to the potential creep effect on cladding integrity of fuels burnt over 45 GWd/tU.This paper explores the burnup influence on cladding creep during dry storage by modelling two different high burnup scenarios (51 GWd/tU and 67 GWd/tU). In addition, sensitivity of the results to the in-reactor average power and power history has been conducted. The computation tool used in this study has been an extension of FRAPCON-3.4 capable of simulating dry storage scenarios. Burnup and average linear power have been shown to make creep grow quite substantially during the first two years in dry storage, adopting a quasi-asymptotic trend from then on. However, even though this profile seems to have a generic nature, the net creep value reached depends not just on integral and average variables, but also on magnitudes describing the entire irradiation history, like linear power history. In none of the cases explored creep approaches the 1% threshold. In-reactor FGR modelling has been highlighted as a key element to get accurate estimates of creep.  相似文献   
5.
This article summarizes the main results of a bench-scale program focused on experimentally assessing the aerosol retention near the tube breach in a tube bundle. The major variables investigated were particle nature (polydispersed TiO 2 agglomerates vs. solid, monodisperse SiO 2 spheres) and Re D (0.8?2.7· 10 5 ). In addition, comparisons to other data sets provided insights into the particle aerodynamic size effect on retention efficiency. Results showed that particle nature substantially affects aerosol retention in the tube bundle: mass retention efficiency was low for TiO 2 agglomerates (less than 30%) whereas it was much higher for SiO 2 particles (around 85%). Retention efficiency is also affected by Re D : its sensitivity was found to follow a log-normal behavior with a maximum retention attained at Re D near 1· 10 5 . This evolution with Re D was similar for both types of compounds. Particle size also influences retention efficiency: the bigger the TiO2 agglomerates the lower retention efficiency (no data were available for SiO 2 ). Among all these variables, particle nature was noted to have a prime importance for in-bundle retention, whereas Re D and particle aerodynamic size, although also affect retention efficiency, did not play such a key role. In light of the results, the presence of retention-inhibiting mechanisms such as fragmentation, resuspension or bouncing has been discussed. The data recorded will enhance the overall understanding of the governing mechanisms involved and will serve as a database against which compare model predictions. Nevertheless, further experimental data would be desirable to set up a sound database.  相似文献   
6.
European designs for the next generation of nuclear reactors incorporate innovative passive systems in their containments to enhance heat removal by condensation under postulated accident conditions. These systems consist of several units of cross-flow finned tube bundles internally cooled with water. So far most of the studies that have been addressed to the issue of heat transfer onto finned surfaces under condensing conditions have involved refrigerants and pure vapor conditions. This study presents a model (HTCFIN) capable of predicting condensation of a cross-flow air–steam mixture onto a single horizontal finned tube. The comparison of HTCFIN predictions to the available databases shows its acceptable accuracy in a wide range of conditions and allows an interpretation of the influence of major variables acting on the scenario. As a consequence, HTCFIN model represents a step forward in the present theoretical capability to estimate heat transfer within containments of next generation of European reactors in the case of a hypothetical accident.  相似文献   
7.
OBJECTIVE: To find the reliability of the coding of diagnoses in the doctor's note in this computer system and to analyse where there are most discrepancies. DESIGN: An observational study. The concordance between the reason for consultation, codified by an external assessor, and the coding of the main diagnosis. SETTING: Health Districts 17 (Murcia/Barrio del Carmen) and 66 (Molina de Segura/La Ribera) in the Autonomous Community of Murcia. PATIENTS: A sub-sample of 228 consultations, belonging to a larger study of 1,904 general medical consultations (total: 98,768 consultations). MEASUREMENTS AND MAIN RESULTS: There were discrepancies between the coding of the reason for consultation and the diagnosis in 23% of the consultations recorded. The reason for consultation was not correctly recorded in 12.3%. The diagnostic group or section with the highest level of agreement was number XVIII or the supplementary section; and with the least agreement in XVII (injuries and adverse side-effects) and Number V covering mental disorders. CONCLUSIONS: Quality control of information and its validation enables errors and problems in the systems to be identified and corrected. This study points to the need to improve the filling-out of the reason for consultation and activity carried out, in order to obtain afterwards a more reliable coding of the diagnosis.  相似文献   
8.
We present 11 lymphoceles in 180 consecutive kidney transplants (6%). We study the potential etiologic factors, symptoms, diagnostic evaluation and treatment, stressing the role of laparoscopy in management of bulky and loculated symptomatic lymphoceles. This technique allows to reduce morbidity, increasing efficacy and shortening hospitalization.  相似文献   
9.
OBJECTIVE: To describe a case of uretero-iliac fistula, an extremely rare condition that is not easily diagnosed. METHODS/RESULTS: Herein we describe a 76-year-old female who had undergone repeated pelvic surgery for adenocarcinoma of the sigmoid. She had a right ureteral fistula that had been managed conservatively by insertion of a ureteral catheter. Diagnosis was made by selective arteriography of the iliac arteries. The patient was submitted to surgery; primary closure of the arterial fistula and nephroureterectomy were performed. CONCLUSIONS: Uretero-iliac fistula should be suspected in patients with a history of repeated pelvic surgery and ureteral catheter placement that present with massive hematuria.  相似文献   
10.
With the availability of new, broad-spectrum antibiotics, initial therapy with a single agent has become an alternative to classic combinations in the management of febrile, neutropenic cancer patients. The aims of this study were to compare the efficacy of ceftazidime and imipenem as empirical monotherapy of febrile episodes in neutropenic patients, and to examine the frequency with which second-line antibiotics (amikacin, vancomycin, or both) were required. A prospective clinical trial was carried out in a single centre. Eligible patients with solid tumours or lymphoma were randomised to receive monotherapy with ceftazidime or imipenem. In the event of no response, amikacin and/or vancomycin were added in 48-72 h intervals (sequentially, or according to clinical or microbiological data). Efficacy was evaluable for 111 assessable episodes. Median neutrophil count at entry was 100 cells/microliters and median duration of neutropenia was 4 days. Febrile episodes were classified as microbiologically (34%) or clinically documented (42%), and fever of unknown origin (24%). Gram-negative infections (57%) predominated over gram-positive isolates (30%). The overall success rate with monotherapy (69% versus 70%), or with modification (20% versus 23%) were equivalent for ceftazidime and imipenem (P = 0.75). The mortality in this series was 5%. Single-agent therapy with either ceftazidime or imipenem is effective for the empirical treatment of febrile episodes in neutropenic patients with solid tumours. Early addition of amikacin and/or vancomycin resolves most failures of the first step.  相似文献   
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