On the Performance of a Two-Stage Vibration Isolation System Which has Geometrically Nonlinear Stiffness

Linear single-stage vibration isolation systems have a limitation on their performance, which can be overcome passively by using linear two-stage isolations systems. It has been demonstrated by several researchers that linear single-stage isolation systems can be improved upon by using nonlinear stiffness elements, especially for low-frequency vibrations. In this paper, an investigation is conducted into whether the same improvements can be made to a linear two-stage isolation system using the same methodology for both force and base excitation. The benefits of incorporating geometric stiffness nonlinearity in both upper and lower stages are studied. It is found that there are beneficial effects of using nonlinearity in the stiffness in both stages for both types of excitation. Further, it is found that this nonlinearity causes the transmissibility at the lower resonance frequency to bend to the right, but the transmissibility at the higher resonance frequency is not affected in the same way. Generally, it is found that a nonlinear two-stage system has superior isolation performance compared to that of a linear two-stage isolator.

Two-stage rumenostomy in buffaloes

Background: Rumenostomy may be performed for therapeutic and digestibility research purposes in bovines, small ruminants and camelids. Several studies requires romenostomy in buffaloes in order to sample ruminal content for laboratorial assays. However, complications and outcome of rumenostomy was poorly studied in buffaloes. Therefore, the aim of the current study was to describe a two-stage rumenostomy technique in buffaloes, focused on intra and post-operative period.Materials, Methods & Results: Nine Murrah buffaloes were submitted to a 36-h and 12-h of food and water fastening. The animals were given acepromazine and maintained in standing position. Flank local anesthesia was carried out. A circular skin incision was carried out in the center of the left flank, followed by divulsion of the external and internal obliques and transversus abdominus muscles, and incision of the peritoneum. Subsequently, a segment of the dorsal aspect of the rumen was grasped and pulled through the flank incision. The rumen was attached to the peritoneum and skin incision margins in four points (dorsal, ventral, cranial and caudal). Additional simple interrupted sutures attaching the rumen serosa to the skin were applied subsequently. Four additional interrupted horizontal mattress sutures were applied equidistantly, taking bites only in the skin and rumen serosa. Following 12 h, the second stage was carried out. The buffaloes were prepared and restrained as performed for the first stage. A circular flap was excised from the exteriorized rumen and the silicone romenostomy cannula was placed. Clinical parameters, postoperative recovery, weight and behavioral pain scale were assessed. Positioning and anesthesia regimen were adequate for the achievement of the procedure. However, two animals fell in the restraint chute during the first surgical stage. Mild ischemia of the exteriorized rumen segment was observed on the second surgical stage, which resulted in less hemorrhage and enhanced cannula positioning. Complete cicatrization and permanent adhesion of the rumen to the skin were achieved. No ruminal leakage to the abdominal cavity occurred. No signs of pain were reported. There were few cases of laxity of the romenostomy opening leading to drop of cannula, myiasis on the margin of the stoma site and few cases of mild ruminal content leakage on the long-term assessment.Discussion: Restraint in standing position was considered adequate, although lateral recumbence constitutes another option. However, higher risk of contamination and technical difficulties in placing the cannulas are expected if lateral recumbence is considered. In other trials using acepromazine, no accidental recumbence occurred. Xylazine was also indicated for chemical restraint of buffaloes. It is known that flexible cannulas provide better anatomic adjustment and adaptation as well as being effective for sampling ruminal content, as seen in the current study. Ruminal leakage is one of the most frequent complications of romenostomy, which may affect animal's welfare. The animals in the current study presented no variations on the body score, even though on those presenting cannula loosening or ruminal content leakage. Moreover, no significant changes of the ruminal content parameters were noticed. Myiasis was also reported following ruminal surgical interventions, which were mainly attributed to extensive breeding. Loss of the cannula, subcutaneous emphysema and suture dehiscence are common complications of romenostomy. Nonetheless, none of those complications were found on the current study. Thus, romenostomy was feasible and efficient for sampling and performing assays of the ruminal content in buffaloes.

Pré-sal e o novo marco regulatório: um estudo sobre o fundo social

This work intends to discuss about the current happenings in oil sector, and how the recent discovery of huge oil reserves on the layer known as Pre-Sal can positively transform in the socioeconomic context, the country. The impact of this huge quantity of natural resources it depends on the legislative policies adopted for the exploration and production (E & P) in the Pre-Salt layer, and the way in which laws are imposed for distribution of such resources. Therefore, it is made a shortly background of the laws from oil exploration, production and distribution, since the monopoly of Petrobras, to nowadays. To this end, an analysis is performed about the Oil Law, and about the possible legislative changes with the new Regulatory Framework. This monograph attempts to prove, based on historical data, socioeconomic facts, and international experiences, using either comparative statistical, that with the discovery in the Pre-Salt area, the best way to optimize the use of these resources, mainly the reduction of social inequality and economic contrasts, a legacy from colonization, would directly those recipes to a National Development Fund, the Social Fund, established by law for the new Regulatory Framework

Approach toward an efficient inoculum preparation stage for suspension BHK-21 cell culture

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

New records of Amblyomma goeldii (Acari: Ixodidae) and description of the nymphal stage

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Spatial dynamics of a population with stage-dependent diffusion

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Mathematical modeling of a continuous alcoholic fermentation process in a two-stage tower reactor cascade with flocculating yeast recycle

Experiments of continuous alcoholic fermentation of sugarcane juice with flocculating yeast recycle were conducted in a system of two 0.22-L tower bioreactors in series, operated at a range of dilution rates (D (1) = D (2) = 0.27-0.95 h(-1)), constant recycle ratio (alpha = F (R) /F = 4.0) and a sugar concentration in the feed stream (S (0)) around 150 g/L. The data obtained in these experimental conditions were used to adjust the parameters of a mathematical model previously developed for the single-stage process. This model considers each of the tower bioreactors as a perfectly mixed continuous reactor and the kinetics of cell growth and product formation takes into account the limitation by substrate and the inhibition by ethanol and biomass, as well as the substrate consumption for cellular maintenance. The model predictions agreed satisfactorily with the measurements taken in both stages of the cascade. The major differences with respect to the kinetic parameters previously estimated for a single-stage system were observed for the maximum specific growth rate, for the inhibition constants of cell growth and for the specific rate of substrate consumption for cell maintenance. Mathematical models were validated and used to simulate alternative operating conditions as well as to analyze the performance of the two-stage process against that of the single-stage process.

Short-term prophylaxis with ciprofloxacin in extended 16-core prostate biopsy

Objective: To evaluate the safety, efficacy and possible complications of 16-core transrectal prostate biopsies using two doses of ciprofloxacin for prophylaxis of infectious complications.Materials and Methods: Sixteen-core prostate biopsies were performed on a number of patients with different signs of potential prostate cancer. Complications were assessed both during the procedure and one week later. After the procedure, urine samples were collected for culture. The rate of post-biopsy complications, hospital visits and hospitalizations were also analyzed. Ciprofloxacin (500 mg) was administered two hours before, and eight hours after the procedure.Results: The overall rate of post-biopsy complications was 87.32%, being 5.4% of those considered major complications due to hemorrhage, or to urinary retention. Eight patients required hospital treatment post-biopsy. Fever occurred in just one patient (0.29%). There was no incidence of orchitis, epididymitis, prostatitis, septicemia, hospitalization, or death. The urine culture showed positive results in five patients (2.15%).Conclusion: One-day prophylaxis with ciprofloxacin proved to be safe and effective in the prevention of infectious complications following 16-core prostate biopsies.

Differentiation of Haemonchus placei from Haemonchus contortus by PCR and by morphometrics of adult parasites and third stage larvae

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Morphology of the first larval stage of Macrobrachium brasiliense (Heller, 1868) (Caridea: Palaemonidae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Bone mineral density in healthy female adolescents according to age, bone age and pubertal breast stage

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Greater level of physical activity associated with better cognitive function in hemodialysis in end stage renal disease

Patients with chronic kidney disease (CKD) have a lower exercise tolerance and poor functional capacity, carry on a sedentary lifestyle. Another important change found in patients with CKD is cognitive dysfunction. Physical inactivity has been associated with cognitive dysfunction in the general population, but few studies have evaluated this association in CKD. To assess the association between physical activity and cognitive function in patients with CKD on hemodialysis (HD). We evaluated 102 patients undergoing HD. The participants completed the International Physical Activity Questionnaire, which assesses the level of physical activity and the Mini Mental State Examination, used for cognitive screening. Patients were divided into three groups according to their level of physical activity (GI: active/GII: irregularly active/GIII: sedentary). It was applied logistic regression analysis and adopted as outcome variable the presence of cognitive impairment and preserving as independent variables those with a probability of statistical difference between groups of less than 0.1. It was considered statistically significant when p less than 0.05. The groups were similar in age, duration of HD, and smoking. Statistically significant difference regarding race, body mass index, diabetes mellitus, underlying disease and degree of cognitive impairment. Regarding laboratory data, the groups differed in terms of creatinine, glucose, hemoglobin and hematocrit. There was significant association with better physical activity and cognitive function, even adjusting for confounding variables. the highest level of physical activity was associated with better cognitive function in CKD patients undergoing HD.

Sedoanalgesia with midazolam and fentanyl citrate controls probe pain during prostate biopsy by transrectal ultrasound

To assess the pain intensity of patients administered midazolam and fentanyl citrate before undergoing transrectal ultrasound-guided prostate biopsy. This was a study in patients with different indications for prostate biopsy in whom 5 mg of midazolam and 50 µg of fentanyl citrate was administered intravenously 3 minutes before the procedure. After biopsy, pain was assessed by use of a visual analogue scale (VAS) in three stages: VAS 1, during probe introduction; VAS 2, during needle penetration into prostate tissue; and VAS 3, in the weeks following the exam. Pain intensity at these different times was tested with stratification by age, race, education, prostate volume, rebiopsy, and anxiety before biopsy. Pain was ranked according to the following scores: 0 (no pain), 1-3 (mild pain), 4-7 (moderate pain), and 8-10 (severe pain). Statistical analysis was performed by using Kruskal-Wallis and Wilcoxon two-tailed tests with a significance of 5%. Pain intensity was not influenced by any risk factors. The mean VAS 1 score was 1.95±1.98, the mean VAS 2 score was 2.73±2.55, and the mean VAS 3 score was 0.3±0.9, showing greater pain at the time of needle penetration than in other situations (VAS 2>VAS 1>VAS 3, p=0.0013, p=0.0001, respectively). Seventy-five percent of patients reported a VAS pain scale of less than 3.1 or mild pain. Intravenous sedation and analgesia with midazolam and fentanyl citrate is a good method for reducing pain caused by prostate biopsy, even during probe insertion.