罐顶对罐壁应力的影响

在大型油罐设计中采用线性理论的方法,分析论述了罐顶对罐壁是否产生影响这一问题。通过对拱顶油罐、浮顶油罐的罐壁边界条件、罐顶边界条件的分析计算,求出各层壁板挠度方程中的待定系数,便可得出其应力。从线性方程中,可看出影响罐壁应力的主要因素是挠度方程中的待定系数。待定系数除受储罐尺寸、液位高度的影响外,还受罐顶重量、罐顶剪力和弯矩的影响。以10万m~3浮顶油罐和拱顶油罐为例,进一步证明,液位是罐壁应力的控制因素,而罐顶重量、罐顶剪力和弯矩对罐壁应力的影响可以忽略不计。     

Comparison of an Antimicrobial Adhesive Drape and Povidone-lodine Preoperative Skin Preparation in Dogs

The antimicrobial efficacy of an adhesive drape applied after a 1-minute alcohol scrub was compared to a povidone-iodine (PI) skin preparation technique in dogs. Each technique was applied to both sides of 15 adult anesthetized dogs on premeasured, clipped areas of skin. Skin bacteria were quantified before, immediately after, and 1 hour after skin preparation. Predominant skin bacteria were isolated by swabbing the skin. The percentages of bacterial reduction immediately after and 1 hour after skin preparation, percentages of negative culture results, cultures with more than five colony-forming units, and the frequency of skin reactions were calculated and analyzed statistically. Drape adhesion was assessed subjectively. The percentage reduction in skin bacteria was significant for both techniques and comparable to that reported in humans. The adhesive drape was significantly less effective in both the immediate and 1-hour periods. Lift occurred in 66% of drape applications but was not associated with high bacterial counts. Acute contact dermatitis was more frequent after skin preparation with PI. There was no difference between the techniques in recovery of potential skin pathogens. The authors conclude that application of this antimicrobial adhesive drape after a 1-minute alcohol scrub is not as effective in the reduction of skin bacteria in dogs as is PI preparation of the skin.     

Hyperlipemia and Ketonuria in an Alpaca and a Llama

An alpaca and a llama in late stages of gestation were evaluated for lethargy, anorexia, and recumbency. Both camelids had cloudy, white, turbid serum, elevated serum triglyceride (1564, 5658 mg/dL, respectively) and cholesterol (158, 297 mg/dL, respectively) concentrations, and ketonuria. Signs of fetal stress were evident ultrasonographically in the alpaca, and a live cria was delivered by Cesarean section performed under general anesthesia. The alpaca developed severe metabolic acidosis, hepatic lipidosis, and acute renal failure secondary to renal lipidosis and died 36 hours after admission despite medical therapy. Histopathology revealed renal and hepatic lipidosis and neutrophilic pancreatitis. The cria died 72 hours after birth. The llama responded to IV electrolyte, dextrose, and regular crystalline insulin therapy. The pregnancy was maintained, and the llama was discharged from the hospital 20 days after admission. Two months after discharge, the llama gave birth to a live, 5 kg cria. Findings of hypertriglyceridemia, hypercholesterolemia, elevated sorbitol dehydrogenase activity, metabolic acidosis, azotemia, and ketonuria occurred in these two camelids. Based on this report, camelids appear to be similar to both horses and cattle in their response to severe energy imbalances in late gestation.     

Evaluation of the long-acting somatostatin analogue Octreotide in the management of insulinoma in three dogs

The response of dogs with insulinoma to surgical and medical management is variable, with the majority developing intractable hypoglycaemia. A long-acting somatostatin analogue, Octreotide (SMS 201–995; Sandostatin) has been useful in the management of hypoglycaemia in humans with insulinoma, and preliminary reports suggest a beneficial clinical response in dogs with insulinoma. The present study objectively evaluated Octreotide in the management of three dogs with immunohistochemically confirmed insulinoma. Octreotide had no benefit over placebo, and little effect on circulating glucose and insulin concentrations despite clearly detectable plasma concentrations of Octreotide. No clinical improvement was apparent in two dogs given Octreotide over a period of two and three weeks. These results contrast with the positive clinical responses noted previously and indicate that further placebo controlled, objective studies are necessary before clear statements on the treatment of insulinoma with Octreotide are made.     

Utilization of cassava peels as substrate for crude protein formation

Mash prepared from cassava peels was inoculated with eitherSacchromyces cerevisiae orCandida tropicalis and then left to ferment for 7 days. Chemical analysis of the fermented mash showed substantial increase in crude protein content and decrease in carbohydrate content of the mash. The results also revealed slight increases in the ash, fibre and lipid content of the fermented mash. It was further observed that, when the mash was supplemented with inorganic nitrogen sources (urea, ammonium sulfate or sodium nitrate) before commencement of fermentation, the amount of crude protein formed was almost doubled. This enhanced crude protein production was highest in the mash supplemented with urea. Temperature of 30 °C, pH of 5.5 and moisture concentration of 130% were found to be optimum for crude protein formation by the organisms growing on the mash.     

Suspected Tension Pneumomediastinum In A Dog: A Case Report

Successful resuscitation of a trauma-induced, suspected tension pneumomediastinum in a dog is presented. The cause was a caudal cervical penetration wound which acted as a one-way valve allowing air to enter, but not exit, the cranial mediastium. Early in the course of hospitalization, respiratory and cardiovascular collapse occurred; an emergent parasternotomy allowed decompression of the mediastinum, and the cradiovascular system immediately responded. The dog made a complete recovery following surgical exploration and removal of contaminated mediastinal tissue. Nine days of intensive care included 24-hour monitoring, oxygen therapy, intravenous crystalloids and colloids, continuous pleural suctioning, nutritional support, antibiotics, and pain control.     

我国饲料工业发展概况

本文对我国饲料工业发展现状、存在问题、措施及对策三个方面进行了综述。     

Landscape change under indirect effects of human use: the Savanna of Central Chile

The Chilean Intermediate Depression to the north of Santiago has experienced a physiognomical transformation from a Prosopis chilensis woodland to an Acacia caven savanna. Today P. chilensis trees are scarce and belong mostly to the larger size classes. By contrast A. caven seems to reproduce frequently and its populations consist of individuals of all size classes. In this paper we document these changes and report the results of tests aimed at determining the causes of these physiognomical changes. We found that livestock, leporids, introduced Mediterranean forbs and agriculture account for differences in seed dispersal and survival of A. caven and P. chilensis, which can explain the documented changes in the Chilean landscape.     

Evaluation of an enzyme-linked immunosorbent assay for diagnosis of trichinellosis in swine.

Experimental and field trials were conducted to evaluate an ELISA for its ability to detect Trichinella-infected domestic swine and to compare ELISA results with muscle-digestion test results. The ELISA used was a commercial double-antibody kit, containing an excretory-secretory antigen, and was evaluated principally for epidemiologic use. Experimentally induced infection in swine (4 groups of 3 pigs each; inoculated with 0, 50, 500 or 5,000 larvae) was detected as early as postinoculation week 4, with seroconversion of all inoculated swine by postinoculation week 8. The rate of seroconversion appeared to be affected by initial larval dose, time after inoculation, and immunocompetence of the individual host. Determination of antibody kinetics generally revealed rapidly increasing antibody titer, followed by its steady decrease in most pigs. Once seropositive, however, all pigs remained seropositive for the duration of the 10-week study. Presence of muscle larvae was confirmed in all infected pigs at termination of the study. We recognize that the experimental conditions may not be truly representative of those under which natural infection develops in pigs; however, the ELISA detected an infected pig with muscle larval density of 0.87 larvae/g of tissue. Results of a field trial (n = 310) indicated no muscle digestion test-positive pigs (35 g of diaphragm muscle digested/pig), but 3 samples tested positive by ELISA for specificity of 99.0%.