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71.
Urban agriculture (UA) is spreading within the Global North, largely for food production, ranging from household individual gardens to community gardens that boost neighborhood regeneration. Additionally, UA is also being integrated into buildings, such as urban rooftop farming (URF). Some URF experiences succeed in North America both as private and community initiatives. To date, little attention has been paid to how stakeholders perceive UA and URF in the Mediterranean or to the role of food production in these initiatives. This study examines the promotion and inclusion of new forms of UA through the practice of URF and contributes to the nascent literature on the stakeholder and public perceptions of UA. It seeks to understand how those perceptions shape the development of new urban agriculture practices and projects. Barcelona (Spain) was used as a Mediterranean case study where UA and URF projects are growing in popularity. Through semi-structured interviews with 25 core stakeholders, we show that UA is largely perceived as a social activity rather than a food production initiative, because the planning of urban gardens in Barcelona was traditionally done to achieve leisure and other social goals. However, several stakeholders highlighted the potential to increase urban fertility through URF by occupying currently unused spaces. As a result, the positive valuation of URF depends on the conceptualization of UA as a social or food production activity. In turn, such conceptualization shapes barriers and opportunities for the development of URF. While most UA-related stakeholders (e.g., food co-ops, NGOs) preferred soil-based UA, newer stakeholders (e.g., architects) highlighted the economic, social and environmental opportunities of local and efficient food production through innovative URF.  相似文献   
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Horseshoeing is a common practice, but effects on the hoof wall are poorly understood. Strain gauges were used to document and compare hoof behavior in vitro during flat weight bearing and after artificial heel elevation. Ten front limbs of Thoroughbred race horses, shod with conventional flat shoes, were used. Eight strain gauges were symmetrically distributed around the toe, quarters, and heels. Each limb was mounted to a testing machine (Kratos K5002; Kratos Dynamômetros, Ltda., Cotia-SP-Brazil) and subjected to a load equivalent to 30% of the donor's body weight. Strains (μ) were acquired by means of a computerized system and the results compared using Friedman and Wilcoxon statistical tests. There was greater strain variation when the heels were elevated. Compression predominated during flat weight bearing, with a tendency to horizontal traction after heel elevation. The changes in strain caused by heel elevation were not always symmetrical. Elevation of the heels tensed the toe and the medial quarter horizontally, increased load at the posterior portion of the hoof capsule, and hindered its expansion.  相似文献   
73.
The objective of this study was to define, in detail, the anatomy of the portal and hepatic veins in the dog in order to establish a procedure for the systematic evaluation of the liver by ultrasonography. Anatomical details were obtained from the formalin fixed livers of ten dogs. The hepatic and portal veins were removed intact from these livers so that a detailed pattern of distribution could be established and the numbers of branches could be counted. Silastic casts were also made of the hepatic and portal veins of two livers, one in situ and one in which it had been removed. The former was to enable the relationship of the portal to the hepatic veins to be established as closely as possible within the animal and the other to provide a model of the distribution of each venous system within the liver. Contrast medium was infused into two other livers and radiographs taken to establish the relationship of each branch to each lobe. It was found that there was a consistent pattern of venous branching to each lobe of the liver in the dog with little variation between individual specimens. All liver lobes contained definite venous branches so that the left lateral and medial, quadrate, right medial and lateral, caudate and papillary veins could be distinguished in each venous system. We believe that an appreciation of this venous distribution will aid in the systematic evaluation of the liver during ultrasonography by enabling identification of each liver lobe. It should be of value for differentiating portal from hepatic veins and veins from dilated bile ducts.  相似文献   
74.
It was the intent of this study to define which, if any, radiographic observations corresponded with specific causes of diffuse infiltrative small bowel disease and if radiographic findings could differentiate inflammatory disease from neoplastic disease and either of them from normal. Bowel spasticity, luminal narrowing, and thumbprinting tend to indicate the presence of tumor more often than inflammatory disease. Increased bowel gas in cats and barium adhesion in dogs and cats suggest that a component of enteritis is present. Decreased bowel gas in dogs is more often associated with obstructive disease, but is not helpful in differentiating diffuse inflammatory disease from diffuse neoplastic disease. While several observations that can foster differentiation of neoplastic from inflammatory disease were found, this study also indicated that the UGI lacks a high degree of predictive value other than to indicate the presence of infiltrative small bowel disease.  相似文献   
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The effects of thiopental, ketamine, diazepam, xylazine, and nitrous oxide, and the combinations of thiopental-nitrous oxide and ketamine-nitrous oxide, on both enflurane-induced electroencephalographic (EEG) spike activity and convulsive behavior were measured quantitatively in atropinized cats receiving enflurane with controlled ventilation. Pretreatments with thiopental, ketamine, and diazepam reduced both EEG spike frequency and amplitude at 2.5% to 4.5% inspired enflurane but did not abolish spike activity. Nitrous oxide (66% of inspired gas) did not significantly alter spike frequency or amplitude during 2.5% to 4.5% inspired enflurane, but the combination of thiopental-nitrous oxide or ketamine-nitrous oxide reduced EEG spike activity during 2.5% inspired enflurane. Enflurane-induced convulsive score was markedly suppressed by thiopental and ketamine and was significantly reduced by diazepam, xylazine and nitrous oxide. The combinations of thiopental-nitrous oxide and ketamine-nitrous oxide greatly reduced behavioral-convulsive responses induced by 2.5% to 4.5% inspired enflurane.  相似文献   
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Objective To determine the analgesic, hemodynamic and respiratory effects, sedation and ataxia in mares of caudal epidural administration of ropivacaine hydrochloride solution. Study design Prospective, single‐dose trial. Animals Ten healthy mares weighing from 475 to 565 kg. Methods Intravascular catheters and an epidural needle were placed after infiltration of the skin and subcutaneous tissues with 2% lidocaine. Ropivacaine (0.5%, 8 or 9 mL) was then injected epidurally at the fifth sacral or sacrococcygeal vertebrae, respectively. Analgesia was determined by lack of sensory perception to electrical stimulation (> 40 milliamps) and absence of response to needle pricks extending from coccyx to S2 dermatomes. Electrocardiogram, heart and respiratory rates, rectal temperature, arterial blood pressure, arterial acid‐base (pH, standard bicarbonate and base excess), gas tensions (PO2, PCO2), PCV, oxyhemoglobin and total solids concentrations, and numerical scores of perineal analgesia, sedation (head drop), and ataxia (position of pelvic limbs) were determined before and during a 5‐hour testing period. Analysis of variance (anova ) with repeated measures was used to detect significant (p < 0.05) differences of mean values from baseline. Results Epidurally administered ropivacaine induced variable analgesia extending bilaterally from coccyx to S2 (three mares), coccyx to S3 (four mares), and coccyx to S4 (three mares), with minimal sedation, ataxia, and cardiovascular and respiratory disturbances of mares. Perineal analgesia was attained at 10 ± 4 minutes and lasted for 196 ±42 minutes (mean ± SD). Five mares demonstrated inadequate perineal analgesia, probably attributable to deviation of the spinal needle from the midline. They were successfully blocked with ropivacaine on another occasion. Epidural ropivacaine significantly reduced repiratory rates of mares and did not change other variables from baseline. Conclusions and clinical relevance Ropivacaine (0.5%, 8 mL 500 kg?1) can be administered caudal epidurally to produce prolonged (> 2.5 hours) bilateral perineal analgesia with minimal sedation, ataxia, and circulatory and respiratory disturbances in standing mares.  相似文献   
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Objective and hypothesis: To determine whether or not there is agreement between the thermodilution and echocardiographic measurement of cardiac output (CO) during normovolemia and acute hemorrhage. The hypothesis was that there will be agreement between echocardiographic measurement of CO (ECO) and thermodilution measurement of CO (TDCO) during normovolemia and acute hemorrhage. Design: CO was measured by both thermodilution and echocardiography during α‐chloralose anesthesia in dogs before and 15 and 30 minutes following acute arterial hemorrhage. Setting: Laboratory investigation. Animals: Eighteen clinically healthy dogs, weighing 20–25 kg, anesthetized with α‐chloralose. Interventions: Acute arterial hemorrhage of approximately 50% of the total blood volume. CO was measured by thermodilution and echocardiography before and 15 and 30 minutes following hemorrhage. Measurements and main results: Acute hemorrhage resulted in a significant decrease in CO. There was a lack of agreement between the 2 methods to measure CO at each time and at all anatomic points of measurement in the aorta and pulmonary artery. Conclusion: There is a lack of agreement between the 2 methods; thus, determination of CO by echocardiography may not be a clinically useful tool following hemorrhage in dogs.  相似文献   
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