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31.
Taking into consideration a study published 10 years ago on sexual disturbances of students at the University of S?o Paulo, the importance of the subject is discussed, along with the creation in 1993 of the Sexuality Project at the university hospital of the University of S?o Paulo School of Medicine. In its first year, this multidisciplinary project attended 140 patients with sexual dysfunctions (associated or not to other clinical manifestations); the majority were younger than 60 years-old, and 80 percent were male. 相似文献
32.
Chestnuts were dehydrated by using a combined method of osmotic dehydration followed by air drying. Samples were osmotically pretreated with sucrose (60% w/w) and glucose (56% w/w) for 8 h, air-dried at temperatures of 45, 55, and 65°C, at a relative humidity of 30% and at a velocity of 2.7 m·s-1 and the experimental data of the drying kinetics were obtained. Whole samples were dried with different peelings: (a) removal of endocarp and pericarp (peeled) and (b) additionally the internal rough surface (cut). In all cases, cut chestnuts show greater drying rates than peeled samples, indicating that a significant mass transfer resistance in the layer nearest to the surface takes place. Peeled samples pretreated with sucrose solutions behave in a similar way to untreated samples. For the rest of the samples, the cut samples osmotically treated with sucrose solutions and all the samples treated with the glucose solution, the drying rates decrease during drying. Drying kinetics are successfully modeled by employing a diffusional model that takes the shrinkage into account. The effective coefficient of water diffusion was evaluated and correlated with temperature. The quality of the final product was monitored by color change. In spite of the fact that the total color difference is not modified by the osmotic treatment, the L*, a*, and b* color coordinates of cut samples treated with sucrose and glucose solutions do undergo changes; the L* and a* coordinates change less than the b*. 相似文献
33.
Subalpine fir (Abies lasiocarpa Hook) lumber containing wetpockets (wetwood) was used for the measurements of gas permeability and the results were then compared to the gas permeability of normal wood, which was free of the wetpockets. The impacts of pretreatment methods were also investigated, including steaming at green condition, steaming at fiber saturation point (FSP), microwave treatment, and radio-frequency treatment. Results from this study demonstrated that both the transverse and the longitudinal gas permeability of subalpine fir wetwood are greater than that of normal wood. There is no significant change in the permeability after 4-h steaming pretreatment at green condition and at FSP. The impacts of microwave and radio-frequency pretreatments were not significant, but the findings cannot be generalized because they may depend on the power intensity applied. 相似文献
34.
JM de Oliveira 《Canadian Metallurgical Quarterly》1998,17(12):967-973
At present, the treatment for acute myocardial infarction is revascularization during the critical initial period of six hours after the beginning of coronary occlusion. Despite the fact that surgery performed within this time period presents a hospital of mortality around 2%, and with excellent results in the long term, it is seldom used due to logistic limitations and capabilities of hospital infrastructures, high costs and the possibility of the surgical team initiating surgery inside the useful time period. Surgery is thus limited to the patients with suitable anatomy, who are not candidates or had failure of thrombolytic/angioplasty therapy and are in the six-hour period after initiation of symptoms. Surgery performed at a later stage has good results if performed in a non emergency situation, specially after the first 72 hours. Surgery continues to be the only treatment for the mechanical complications of infarction, and good results have recently been shown in ventricular septal ruptures, with hospital mortality of 14%, due to the use of an endoventricular patch in patients operated early, before the consequences of low cardiac output develop at systemic level. In the surgical treatment of mitral regurgitation, the tendency has been to use repair techniques whenever possible, but still with hospital mortality up to 15%. The recent advances of the techniques and tactics of myocardial preservation during surgery have made a very significant contribution to the better results we see today. 相似文献
35.
D Ayres-de-Campos JL Silva-Carvalho C Oliveira I Martins-da-Silva J Silva-Carvalho L Pereira-Leite 《Canadian Metallurgical Quarterly》1995,10(8):2010-2016
In this study, we evaluated the reproducibility of analysis of basal body temperature graphs under optimized conditions for agreement. A total of 160 recordings were selected from spontaneous cycles of infertile women and analysed by three experienced clinicians using uniform criteria. Agreement at the various stages of analysis was assessed by the 'proportions of agreement' with 95% confidence intervals. Agreement in identification of the thermal nadir was clearly superior to that reported in previous publications. Reproducibility of 'ovulatory' graph features (i.e. biphasic graphs and adequate thermal shifts) was excellent. Agreement in classification of monophasic graphs and inadequate thermal shifts, although lower, was still good. Thus, with experienced observers and uniform criteria, a good agreement can be achieved in analysis of the most important parameters of the basal body temperature graph. We believe that an effort should be made to generalize the use of uniform analysis criteria, because only then can results from different institutions be compared and the remaining clinical evaluation of the method be performed. 相似文献
36.
J. De Caigny J. F. Camino R. C. L. F. Oliveira P. L. D. Peres J. Swevers 《国际强度与非线性控制杂志
》2012,22(5):535-558
》2012,22(5):535-558
This paper presents synthesis conditions for the design of gain‐scheduled dynamic output feedback controllers for discrete‐time linear parameter‐varying systems. The state‐space matrix representation of the plant and of the controller can have a homogeneous polynomial dependency of arbitrary degree on the scheduling parameter. As an immediate extension, conditions for the synthesis of a multiobjective ??∞ and ??2 gain‐scheduled dynamic feedback controller are also provided. The scheduling parameters vary inside a polytope and are assumed to be a priori unknown, but measured in real‐time. If bounds on the rate of parameter variation are known, they can be taken into account, providing less conservative results. The geometric properties of the uncertainty domain are exploited to derive finite sets of linear matrix inequalities based on the existence of a homogeneous polynomially parameter‐dependent Lyapunov function. An application of the control design to a realistic engineering problem illustrates the benefits of the proposed approach. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
37.
Jorge Blasco Julio Cesar Hernandez-Castro 《Journal of Network and Computer Applications》2012,35(1):491-501
Steganographic techniques allow users to covertly transmit information, hiding the existence of the communication itself. These can be used in several scenarios ranging from evading censorship to discreetly extracting sensitive information from an organization. In this paper, we consider the problem of using steganography through a widely used network protocol (i.e. HTTP). We analyze the steganographic possibilities of HTTP, and propose an active warden model to hinder the usage of covert communication channels. Our framework is meant to be useful in many scenarios. It could be employed to ensure that malicious insiders are not able to use steganography to leak information outside an organization. Furthermore, our model could be used by web servers administrators to ensure that their services are not being abused, for example, as anonymous steganographic mailboxes. Our experiments show that steganographic contents can be successfully eliminated, but that dealing with high payload carriers such as large images may introduce notable delays in the communication process. 相似文献
38.
Dai JD Winkel V Oliveira JB Jen CK 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1992,39(6):722-729
An approximate analysis of the weakly guiding cladded acoustic fiber consisting of a core and infinite thick cladding both with hexagonal crystal symmetry is presented. The crystalline Z axis is parallel to the fiber axis. Weak guidance conditions require that the stiffness constants of the core are slightly less than those of the cladding, and the density of the core and cladding are almost the same. Approximate dispersion and cutoff equations are derived for all pure guided modes. Dispersion curves of several lower-order guided torsional, radial-axial and flexural modes are evaluated using both exact and approximate formulas and they are in good agreement. A simple approximate dispersion equation for leaky (longitudinal-type) modes is also obtained. 相似文献
39.
Tiago Morais Alexandre L. Seabra Brbara G. Patrício Marta Guimares Mrio Nora Pedro F. Oliveira Marco G. Alves Mariana P. Monteiro 《International journal of molecular sciences》2021,22(11)
Visceral adipose tissue (VAT) metabolic profiling harbors the potential to disentangle molecular changes underlying obesity-related dysglycemia. In this study, the VAT exometabolome of subjects with obesity and different glycemic statuses are analyzed. The subjects (n = 19) are divided into groups according to body mass index and glycemic status: subjects with obesity and euglycemia (Ob+NGT, n = 5), subjects with obesity and pre-diabetes (Ob+Pre-T2D, n = 5), subjects with obesity and type 2 diabetes under metformin treatment (Ob+T2D, n = 5) and subjects without obesity and with euglycemia (Non-Ob, n = 4), used as controls. VATs are incubated in culture media and extracellular metabolite content is determined by proton nuclear magnetic resonance (1H-NMR). Glucose consumption is not different between the groups. Pyruvate and pyroglutamate consumption are significantly lower in all groups of subjects with obesity compared to Non-Ob, and significantly lower in Ob+Pre-T2D as compared to Ob+NGT. In contrast, isoleucine consumption is significantly higher in all groups of subjects with obesity, particularly in Ob+Pre-T2D, compared to Non-Ob. Acetate production is also significantly lower in Ob+Pre-T2D compared to Non-Ob. In sum, the VAT metabolic fingerprint is associated with pre-diabetes and characterized by higher isoleucine consumption, accompanied by lower acetate production and pyruvate and pyroglutamate consumption. We propose that glucose metabolism follows different fates within the VAT, depending on the individuals’ health status. 相似文献
40.
M A Rossi S Zucoloto J E Dutra de Oliveira P F Becker J S Oliveira 《Archivos latinoamericanos de nutrición》1978,28(1):29-40
A study of the effect of long-term alcohol consumption on the liver of well-nourished rats is described. Rats fed for 16 weeks on a semipurified diet supplemented with high levels of vitamins and lipotropic factors and alcohol corresponding to 35% of the total caloric intake developed marked fatty changes of the liver. Mild fatty changes were observed in pair-fed controls receiving as isoenergetic equivalent of sucrose instead of alcohol. Intracellular hyaline bodies, corresponding ultrastructurally to giant mitochondria were abundantly found in the hepatocytes of alcoholic rats, while in the controls they were not seen. Te findings in this investigation are postulated to provide further evidence that the long-term intake of alcohol exerts a direct causative role in the pathogenesis of liver damage. 相似文献