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1.
Ventura Francesca Facini Osvaldo Piana Stefano Rossi Pisa Paola 《Canadian Metallurgical Quarterly》2010,136(2):81-89
It has long been recognized that reliable, robust, and automated instrumentation for the measurement of soil moisture content can be extremely useful, if not essential, in hydrological, environmental, and agricultural applications. A number of automated techniques for point measurement of soil water content have been developed to operational level over the past few decades. While each of those techniques has been individually calibrated by the gravimetric method, typically under laboratory conditions, there have been few studies that made a direct comparison between the various techniques, particularly under field conditions. This paper compares ECH2O probes, EC-5 (both sensors based on capacitance measurements, developed by Decagon Devices) and time domain reflectometer sensors (CS616 Campbell Scientific Water Content Reflectometer), with gravimetric data and with each other, under field conditions. Data were collected during two field experiments characterized by different soils and a wide range of soil moistures, resulting from irrigation/drying cycle. Results show that all the tested probes give acceptable results after being calibrated in the field. The capacitive sensors can be used in each type of soil with the same calibration equation, independently from depth, with root mean square error (RMSE) ranging between 2.5 and 3.6%. Time Domain Reflectometry probes showed a dependence on depth but a lower RMSE (1.6%). 相似文献
2.
Greenberg David J.; Scott Steven B.; Pisa Anthony; Friesen Deloss D. 《Canadian Metallurgical Quarterly》1975,43(4):498
To determine whether the addition of milieu principles to a contingency program increases its effectiveness, 2 treatment programs in a mental hospital were compared: (a) a social learning or token economy approach and (b) a combined social learning and milieu approach in which patients were given increased decision-making responsibilities, group pressures were used, and both were integrated with response-contingent management. 37 patients (mean age, 34.9 yrs) were on the token economy ward and 37 (mean age, 33.2 yrs) were on the combined treatment ward. Because the patients in the combined social-learning-milieu program spent significantly more days out of the hospital during the 1-yr experimental period, it is concluded that the program was more effective than the token economy in promoting the generalization of adaptive inhospital behavior to community settings. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
R Scuderi KA Palucka K Pokrovskaja M Bj?rkholm KG Wiman P Pisa 《Canadian Metallurgical Quarterly》1996,87(8):3360-3367
Using Western blot analysis, we examined cyclin E and cyclin A protein levels in 19 patients with acute lymphoblastic leukemia ([ALL] 15 B-ALL and four T-ALL). Whereas normal, nonproliferating peripheral blood mononuclear cells (PBMCs) expressed low levels of the 50-kD cyclin E, ALL blasts in the peripheral blood, although showing low-level or no proliferation as judged by FACS/cell-cycle analysis and cyclin A protein levels, expressed high levels of cyclin E, with a mean value similar to that of the proliferating Burkitt's lymphoma cell line, Akata. The accumulation of a protein shown to shorten the G1 phase of the cell cycle, cyclin E, in growth-delayed leukemic blasts may reflect the malignant status of these cells. Before treatment, B-ALL cells expressed predominantly the 50-kD cyclin E. T-ALL samples displayed the 50-kD cyclin E protein and a smaller, approximately 43-kD cyclin E species. In paired B-ALL samples taken before treatment and at relapse, we found a significant overexpression of the 50-kD protein in relapsed samples (P < .006), plus the presence of up to four additional smaller-molecular-weight species of cyclin E, illustrating clear diagnosis versus relapse differences. Cyclin E expression in ALL blasts may correlate to the relative malignant status of the cells, with higher protein levels reflecting a more advanced stage of the disease and a greater potential to proliferate under permissive conditions. 相似文献
4.
12 male hooded Long-Evans rats were divided into groups for either a control operation or a lesion of the fimbria-fornix. Ss were trained in several versions of a barpress, spatial alternation task. In free operant conditions across 5 experiments, Ss with fimbria-fornix lesions showed adequate alternation performance when the bars were relatively separated by placement either at the ends of an alley or at the ends of the arms of a T-maze, but they were impaired when bars were adjacent. Lesioned Ss also failed to alternate after interpolation of either baffles or a 10-sec delay in the stem, both of which resulted in intervening turning responses before each choice. Results are accounted for by a failure to discriminate memories of relevant, discrete events from those of similar, intervening events. (41 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
This paper presents a method for analyzing the stability of small-signal microwave amplifiers with any topology. This analysis is performed using the Nyquist criterion and allows detection of the so-called odd-mode instabilities. The method is easily applicable by using commercially available microwave CAD. © 1998 John Wiley & Sons, Inc. Int J RF and Microwave CAE 8: 293–302, 1998. 相似文献
6.
Pedro T. Pisa Edwige Landais Barrie Margetts Hester H. Vorster Christine M. Friedenreich Inge Huybrechts 《Critical reviews in food science and nutrition》2018,58(1):37-61
Objective: To carry out an inventory on the availability, challenges, and needs of dietary assessment (DA) methods in Africa as a pre-requisite to provide evidence, and set directions (strategies) for implementing common dietary methods and support web-research infrastructure across countries. Methods: The inventory was performed within the framework of the “Africa's Study on Physical Activity and Dietary Assessment Methods” (AS-PADAM) project. It involves international institutional and African networks. An inventory questionnaire was developed and disseminated through the networks. Eighteen countries responded to the dietary inventory questionnaire. Results: Various DA tools were reported in Africa; 24-Hour Dietary Recall and Food Frequency Questionnaire were the most commonly used tools. Few tools were validated and tested for reliability. Face-to-face interview was the common method of administration. No computerized software or other new (web) technologies were reported. No tools were standardized across countries. Conclusions: The lack of comparable DA methods across represented countries is a major obstacle to implement comprehensive and joint nutrition-related programmes for surveillance, programme evaluation, research, and prevention. There is a need to develop new or adapt existing DA methods across countries by employing related research infrastructure that has been validated and standardized in other settings, with the view to standardizing methods for wider use. 相似文献
7.
Lidia Delgado Christian M. Heckmann Flavio Di Pisa Louise Gourlay Prof. Francesca Paradisi 《Chembiochem : a European journal of chemical biology》2021,22(7):1223-1231
β-Glucosidases are used in the food industry to hydrolyse glycosidic bonds in complex sugars, with enzymes sourced from extremophiles better able to tolerate the process conditions. In this work, a novel β-glycosidase from the acidophilic organism Alicyclobacillus herbarius was cloned and heterologously expressed in Escherichia coli BL21(DE3). AheGH1 was stable over a broad range of pH values (5–11) and temperatures (4–55 °C). The enzyme exhibited excellent tolerance to fructose and good tolerance to glucose, retaining 65 % activity in the presence of 10 % (w/v) glucose. It also tolerated organic solvents, some of which appeared to have a stimulating effect, in particular ethanol with a 1.7-fold increase in activity at 10 % (v/v). The enzyme was then applied for the cleavage of isoflavone from isoflavone glucosides in an ethanolic extract of soy flour, to produce soy isoflavones, which constitute a valuable food supplement, full conversion was achieved within 15 min at 30 °C. 相似文献
8.
Dr. Cecilia Pozzi Dr. Flavio Di Pisa Dr. Filomena De Luca Dr. Manuela Benvenuti Prof. Jean Denis Docquier Prof. Stefano Mangani 《ChemMedChem》2018,13(14):1437-1446
β‐Lactamases (BLs) are important antibiotic‐resistance determinants that significantly compromise the efficacy of valuable β‐lactam antibacterial drugs. Thus, combinations with BL inhibitor were developed. Avibactam is the first non‐β‐lactam BL inhibitor introduced into clinical practice. Ceftazidime–avibactam represents one of the few last‐resort antibiotics available for the treatment of infections caused by near‐pandrug‐resistant bacteria. TRU‐1 is a chromosomally encoded AmpC‐type BL of Aeromonas enteropelogenes, related to the FOX‐type BLs and constitutes a good model for class C BLs. TRU‐1 crystals provided ultrahigh‐resolution diffraction data for the native enzyme and for its complex with avibactam. A comparison of the native and avibactam‐bound structures revealed new details in the conformations of residues relevant for substrate and/or inhibitor binding. Furthermore, a comparison of the TRU‐1 and Pseudomonas aeruginosa AmpC avibactam‐bound structures revealed two inhibitor conformations that were likely to correspond to two different states occurring during inhibitor carbamylation/recyclization. 相似文献
9.
Pacheco M Pisa D García-Gómez P Carrasco L Juarranz A 《Microscopy research and technique》2007,70(11):975-986
Candida albicans is considered the main pathogenic yeast responsible for a multitude of infective disorders. However, other yeasts, such as Candida famata, are being recognized as potential emerging pathogens that cause several types of infections in humans and animals. Consequently, we have investigated the adhesion and internalization of Candida famata into monocytes and epithelial cells. The interaction of the yeast with the cells is very rapid and takes place during the first 15 min of injection. However, the affinity of the yeast for the cells varies, THP-1 (human monocytes) being the highest and followed in decreasing order by HeLa (human carcinoma), HaCaT, and Pam-212 (human and mouse keratinocytes, respectively). Heat inactivation or treatment with nystatin, significantly decreases yeast adhesion to cells. Immunofluorescence, as well as scanning and transmission electron microscopy, reveals that cell lines are able to internalize C. famata. At 48 h after infection, most of the yeasts located inside cells appear degraded, but some yeasts recovered from lysed cells, were still viable. Adhesion and internalization of C. famata into HeLa cells were found to be lower than those of C. albicans and C. glabrata, but higher than those of S. cerevisiae. In addition, infection with C. famata results in actin microfilaments rearrangement. This article presents novel data in the interaction of this pathogenic yeast with mammalian cells. 相似文献
10.
PMMA and PMMA/10 wt% nano-Al2O3 fibre mats were produced by means of electrospinning and used as reinforcing phase of poly(ε-caprolactone) matrix. The composite
films were fabricated by means of film-stacking technique. SEM observations showed good wettability of PMMA-based fibres by
the PCL matrix, confirming that a strong interface was formed. The Al2O3 nanoparticles were well-distributed along the polymeric fibres. The introduction of PMMA fibres as a reinforcement led to
a clear benefit in terms of the mechanical strength (11.5 ± 0.5 MPa), the value for neat PCL being 8.2 ± 2.2 MPa. The tensile
strength was further increased when the fibres were loaded with nano-Al2O3 (14.4 ± 0.6 MPa) due to both the presence of the ceramic filler and the smaller diameter of the composite fibres. A less
marked improvement was instead found on stiffness. 相似文献