The Influence of Location on Productivity: Manufacturing Technology in Rural and Urban Areas

ABSTRACT Policies to counter the growing discrepancy between economic opportunities in rural and urban areas have focused predominantly on expanding manufacturing in rural areas. Fundamental to the design of these strategies are the relative costs of production and productivity of manufacturing in rural compared to urban areas. This study develops information that can be used to assess the productivity of manufacturing in rural and urban areas. Production functions are estimated for the meat-products and household-furniture industries to investigate selected aspects of location and productivity. The results show that the effect of location on productivity varies with industry, size, and the timing of entry. Although the analysis is specific to two industries, it suggests that development policies targeting manufacturing can be more effective if they focus on industries and plants with characteristics that predispose them to the locations they support.     

Equilibrium adsorption of isoproturon on soil and pure clays

The adsorption of isoproturon on soil and pure clay minerals has been investigated as a means of understanding its mobility in soils. Measured adsorption coefficients are correlated with soil and clay mineral properties. Soil organic matter controlled the adsorption of isoproturon at organic carbon contents exceeding 27 g kg^?1, whereas at less than this threshold, clay mineral surfaces appeared to control adsorption. The effect of varying temperature suggests that adsorption of isoproturon is a physical process. From the comparison of the fits of linear, Freundlich, and Langmuir adsorption isotherms to the data, the adsorption is best described as a partition process.     

A Comparison of Steady State and Transient Thermography Techniques Using a Healing Tendon Model

Steady state and transient thermal techniques were used to define the thermal signatures of surgically sectioned and sham-operated common calcanean tendons in four dogs. All limbs were imaged from the lateral side using an Inframetrics 525 system at - 1, 2, 4, 6, and 8 weeks after surgery. Individual video frames were used to compute absolute surface temperatures and rewarm curves for five predetermined 1 cm2 skin areas. Angiography was performed at each observation period to correlate changes in vascular morphology and thermal data. Thermal signatures and angiograms were similar in all animals before surgery. At 2 and 4 weeks after surgery, the absolute surface temperatures of the entire lateral crus area were elevated in three of four animals. During weeks 6 and 8, the surface temperatures, rewarm curves, and angiograms returned to presurgical values for the controls. Skin areas over the repaired tendons remained warmer and were shown to correlate with vascular proliferation by transient but not steady state techniques. Steady state and transient thermal imaging techniques can be used to detect vascular changes in the area around a healing tendon. However, our data indicate that transient thermal techniques are more suitable than steady state methods for localizing vascular disturbances in tissues. Thermographic imaging techniques may become a reliable noninvasive method to monitor wound healing processes if starting temperatures, cool down techniques, and time intervals for data collection are fully evaluated in future studies using transient thermal imaging protocols.     

Development of Parenchymal Abdominal Organ Models for Use in Teaching Veterinary Soft Tissue Surgery

Models of the canine spleen, kidney, and liver were made from soft plastic to simulate the organs of the live animal as closely as possible in appearance and tissue handling properties. Each organ model was independently evaluated by five small animal surgeons who performed several common surgical procedures on each model. All models had a realistic appearance and, with the exception of one tissue handling problem with the kidney model, and one with the liver model, tissue handling properties of the models were comparable to those of the organs in the live animal. All models were useful for teaching each of the procedures evaluated.     

Effect of Desmopressin Acetate on Bleeding Times and Plasma von Willebrand Factor in Doberman Pinscher Dogs with von Willebrand''s Disease

Effects of desmopressin acetate (1-desamino-8-D-arginine vasopressin [DDAVP]) on plasma von Willebrand factor (vWf) were studied in 12 purebred Doberman pinschers confirmed to have von Willebrand's disease (vWd) (plasma vWf antigen [vWf:Ag] concentrations, less than 30 U/dl). Twelve dogs had subnormal plasma botrocetin cofactor (BCf) activity and 11 dogs had prolonged buccal mucosa bleeding times. Tranquilization of three dogs with lenperone and three dogs with xylazine did not induce significant changes in mean plasma vWf:Ag concentrations or mean BCf activities. Thirty and 120 minutes after administration of DDAVP (1 micrograms/kg subcutaneously), there was significant shortening of the mean buccal mucosa bleeding time. Ten dogs responded to DDAVP with increases in BCf activity which exceeded 10 U/dl at 30 or 120 minutes, or both, after the drug was administered. At the same time, increases in plasma vWf:Ag concentrations were smaller than the increases in BCf activity. It was shown by multimeric analysis that primarily the higher molecular weight forms of vWf increased in plasma in response to DDAVP.     

Effect of Ethylene Oxide Sterilization and Storage Conditions on Canine Cortical Bone Harvested for Banking

Two hundred seventeen cortical bones were harvested cleanly and prepared for banking for 2 months by using one of three types of packing materials, two ethylene oxide (EO) concentrations and procedures, and two storage temperatures. Bone subjected to the various treatments was compared to freshly harvested cortical bone and bone tested immediately after sterilization. Parameters evaluated were handling characteristics during preparation for and placement of a 3.5 mm cortex screw, and the percentage of weight lost as water when the bones were dried in an oven at 100 degrees C for 72 hours. Methods of sterilization, packaging material, and temperature of storage affected the handling characteristics and dehydration of the bone specimens. Twelve per cent EO at an elevated temperature and pressure, paper packaging, and room temperature storage appeared to cause the most significant changes. The use of 84% EO at room temperature and pressure, polyethylene wrapping material, and storage at -20 degrees C appeared to protect bone from dehydration. There was an increase in cracking and splitting of the bones as the percent of water loss decreased (indicating dehydration at the time of testing). Dehydration due to sterilization and storage processes may lead to difficulty in preparing bone for insertion of a bone screw and subsequently jeopardizing the stability of a repair in which such alloimplants are used.     

Vitrification with Glutamine Improves Maturation Rate of Vitrified / Warmed Immature Bovine Oocytes

The current study examined the protective effects of l ‐glutamine and cytochalasin B during vitrification of immature bovine oocytes. Oocyte vitrification solution (PBS supplemented with 10% FCS, 25% EG, 25% DMSO and 0.5 m trehalose) was the vitrification control. Treatments were the addition of 7 μg/ml cytochalasin B, 80 mm glutamine or both cytochalasin and glutaminine for 30 s. After warming, oocytes were matured in vitro for 24 h, fixed and stained with Hoechst (33342) for nuclear maturation evaluation. l ‐glutamine improved the vitrified/warmed immature bovine oocytes viability (32.8%), increasing the nuclear maturation rates compared to other treatments and the no treatment vitrified control (17.4%). There was, however, no effect of cytochalasin B on in vitro maturation (14.4%).     

COMPARATIVE MAGNETIC RESONANCE IMAGING FINDINGS BETWEEN GLIOMAS AND PRESUMED CEREBROVASCULAR ACCIDENTS IN DOGS

Cerebrovascular accidents, or strokes, and gliomas are common intraaxial brain lesions in dogs. An accurate differentiation of these two lesions is necessary for prognosis and treatment decisions. The magnetic resonance (MR) imaging characteristics of 21 dogs with a presumed cerebrovascular accident and 17 with a glioma were compared. MR imaging findings were reviewed retrospectively by three observers unaware of the final diagnosis. Statistically significant differences between the appearance of gliomas and cerebrovascular accidents were identified based on lesion location, size, mass effect, perilesional edema, and appearance of the apparent diffusion coefficient map. Gliomas were predominantly located in the cerebrum (76%) compared with presumed cerebrovascular accidents that were located mainly in the cerebellum, thalamus, caudate nucleus, midbrain, and brainstem (76%). Gliomas were significantly larger compared with presumed cerebrovascular accidents and more commonly associated with mass effect and perilesional edema. Wedge‐shaped lesions were seen only in 19% of presumed cerebrovascular accidents. Between the three observers, 10–47% of the presumed cerebrovascular accidents were misdiagnosed as gliomas, and 0–12% of the gliomas were misdiagnosed as cerebrovascular accidents. Diffusion weighted imaging increased the accuracy of the diagnosis for both lesions. Agreement between observers was moderate (κ=0.48, P<0.01).