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An abstract of the article "Evaluation of protection against virulent bovine viral diarrhea virus type 2 in calves that had maternal antibodies and were vaccinated with a modified-live vaccine," by A. D. Zimmerman, R. E. Boots, J. L. Valli, and C. C. L. Chase is presented

In the present paper, we consider mechanical properties of an ideal hexagonal close-packed (HCP) crystal lattice. We construct three models for describing the elastic characteristics of metals with HCP lattice. Using examples of nine metals with different degree of geometric imperfection (beryllium, hafnium, cadmium, cobalt, magnesium, rhenium, titanium, zinc, and zirconium), we show that including the moment interaction into the model leads to a more accurate description of the elastic properties than taking into account the geometric features of a specific lattice. We also show that, depending on the type of the electron shell, it is efficient to use different models; namely, for d-elements, it suffices to use the two-parameter force model, while for the s-elements, it is required to take the moment interaction into account. [ABSTRACT FROM AUTHOR]

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Understanding the nutritional quality of wildlife foods is important for management and conservation efforts. We report the gross energy and macronutrient content of 10 plant species consumed by endangered Hawaiian Moorhens (Gallinula chloropus sandvicensis) along with gross energy and macronutrient content of three plant species not known to be consumed by moorhen. We also report the same information for Urochloa mutica that is consumed when it is < 10 cm tall, but not when it is taller. We also compared macronutrient composition of plant species collected from sites with different soil moisture levels. Energy density, fat, ash, nitrogen, protein, carbohydrates, and fiber of these wetland plants were similar across soil moisture categories, but differed among plant species. We tested for rank consistency of nutrient values across species to determine if some were consistently high across measures, and we tested whether there were differences in energy and protein content between natives and non- natives, and between species consumed versus not eaten. Rank values of macronutrients were inconsistent across species, and we found no differences in energy or protein across groups of species. Information on Hawaiian Moorhen nutritional requirements and the species' ability to metabolize these different plants will help inform wetland managers. [ABSTRACT FROM AUTHOR]

A multi-pinhole collimation device is developed that uses the gamma camera detectors of a clinical SPECT or SPECT-CT scanner to produce high-resolution SPECT images. The device consists of a rotating cylindrical collimator having 22 tungsten pinholes with 0.9 mm diameter apertures and an animal bed inside the collimator that moves linearly to provide helical or ordered-subsets axial sampling. CT images also may be acquired on a SPECT-CT scanner for purposes of image co-registration and SPECT attenuation correction. The device is placed on the patient table of the scanner without attaching to the detectors or scanner gantry. The system geometry is calibrated in-place from point source data and is then used during image reconstruction. The SPECT imaging performance of the device is evaluated with test phantom scans. Spatial resolution from reconstructed point source images is measured to be 0.6 mm full width at half maximum or better. Micro-Derenzo phantom images demonstrate the ability to resolve 0.7 mm diameter rod patterns. The axial slabs of a Micro-Defrise phantom are visualized well. Collimator efficiency exceeds 0.05% at the center of the field of view, and images of a uniform phantom show acceptable uniformity and minimal artifact. The overall simplicity and relatively good imaging performance of the device make it an interesting low-cost alternative to dedicated small animal scanners. [ABSTRACT FROM AUTHOR]

This paper explores user satisfaction with making use of paratransit in Bandung, Indonesia. User perceptions of attributes are analyzed using factor analysis to find representing attribute types and factors of service quality. Ordinal probit analysis is employed to explore the characteristics of users regarding their perception of satisfaction with the paratransit service. Binary logistic analysis is undertaken to predict users' choice probability in making use of paratransit in the future when there is a service improvement. The study reveals that what may be of importance in developed countries carries a different weight of importance for paratransit users. This fact can be explained by describing the characteristics of users that expressed their satisfaction, which also explains the target market for this mode. The analysis reveals the notion that financial motives seem to dominate when users select to use paratransit. [ABSTRACT FROM AUTHOR]

Many of the threats to the persistence of populations of sensitive species have physiological or pathological mechanisms, and those mechanisms are best understood through the inherently integrative discipline of physiological ecology. The desert tortoise was listed under the Endangered Species Act largely due to a newly recognized upper respiratory disease thought to cause mortality in individuals and severe declines in populations. Numerous hypotheses about the threats to the persistence of desert tortoise populations involve acquisition of nutrients, and its connection to stress and disease. The nutritional wisdom hypothesis posits that animals should forage not for particular food items, but instead, for particular nutrients such as calcium and phosphorus used in building bones. The optimal foraging hypothesis suggests that, in circumstances of resource abundance, tortoises should forage as dietary specialists as a means of maximizing intake of resources. The optimal digestion hypothesis suggests that tortoises should process ingesta in ways that regulate assimilation rate. Finally, the cost-of-switching hypothesis suggests that herbivores, like the desert tortoise, should avoid switching food types to avoid negatively affecting the microbe community responsible for fermenting plants into energy and nutrients. Combining hypotheses into a resource acquisition theory leads to novel predictions that are generally supported by data presented here. Testing hypotheses, and synthesizing test results into a theory, provides a robust scientific alternative to the popular use of untested hypotheses and unanalyzed data to assert the needs of species. The scientific approach should focus on hypotheses concerning anthropogenic modifications of the environment that impact physiological processes ultimately important to population phenomena. We show how measurements of such impacts as nutrient starvation, can cause physiological stress, and that the endocrine mechanisms involved with stress can result in disease. Finally, our new syntheses evince a new hypothesis. Free molecules of the stress hormone corticosterone can inhibit immunity, and the abundance of "free corticosterone" in the blood (thought to be the active form of the hormone) is regulated when the corticosterone molecules combine with binding globulins. The sex hormone, testosterone, combines with the same binding globulin. High levels of testosterone, naturally occurring in the breeding season, may be further enhanced in populations at high densities, and the resulting excess testosterone may compete with binding globulins, thereby releasing corticosterone and reducing immunity to disease. This sequence could result in physiological and pathological phenomena leading to population cycles with a period that would be essentially impossible to observe in desert tortoise. Such cycles could obscure population fluctuations of anthropogenic origin. [ABSTRACT FROM AUTHOR]

In this study, investigations were made as to the effect of the maceral compositions and mineral matter content of Azdavay and Kurucasile coals on the coking property. Chemical and maceral analyses and coking properties were determined for the products of the float-sink procedure. The coking properties were established on the basis of free swelling index and Ruhr dilatometer tests. Maceral analyses showed that as the ash content of a coal containing both high and medium volatile matter increases, its effective maceral proportion decreases, and the coking property is affected in an unfavorable way. [ABSTRACT FROM AUTHOR]

An original iterative procedure has been developed to obtain energy spectrum of neutral and charged excitons (positive and negative trions) in spherical semiconductor quantum dots (QD) imbedded into a dielectric material. Numerical calculations are made using the effective mass approximation and Hartree-Fock method. A combined effect of heterointerface polarization (image force potential) and finite band-off-sets on the energy spectrum of excitons and trions in QDs is considered for the first time. It is shown that binding energies of excitons and trions in such QDs can be substantially larger than those in bulk semiconductors due to spatial and ‘dielectric’ confinement effects. [ABSTRACT FROM AUTHOR]

The accurate diagnosis of Dementia of the Alzheimer's Type (DAT) continues to be an area of difficulty for the fields of neuropsychology and neurology. The introduction of new medications that appear to mediate the insidious progression of the disorder increases the need for timely differentiation of DAT from other dementia-related disorders. The present study examined the relationship between hemispheric differences in regional cerebral blood flow with corresponding lateral neuropsychological processing deficits in patients with DAT. Eighty patients with a diagnosis of DAT were administered Single Photon Emission Computerized Tomography (SPECT) scans and a battery of left and right hemisphere neuropsychological-based tasks. The results of ANOVA indicated that patients with DAT who were not suffering from perfusion deficits exhibited significantly fewer neuropsychological deficits than did patients with DAT who had perfusion deficits. The neuropsychological tests that measured verbal ability, logical memory, word-pair learning, reading, arithmetic, and visual-perceptual organization were all significantly lower in the group with perfusion deficits. Further analysis indicated that patients with left hemisphere perfusion deficits tended to have poorer neuropsychological skills than did individuals with right hemisphere perfusion deficits, diffuse perfusion deficits, and no perfusion deficits. A Stepwise Discriminant Analysis was unable to use the neuropsychological variables to classify patients accurately into perfusion deficit groups. [ABSTRACT FROM AUTHOR]

Three important mechanisms that contribute to the compression of municipal solid waste are instantaneous compression in response to applied load, secondary mechanical creep, and time-dependent biological decomposition. A composite compressibility model that explicitly takes these mechanisms into account was developed and implemented in a computer program to calculate landfill settlements. The model performance was assessed using data from the Bandeirantes Landfill, which is a well-documented landfill located in Sao Paulo, Brazil, and upon which an instrumented test fill was constructed. Model parameter values were obtained by nonlinear regression analysis, and it was found that the composite model tracked observed patterns of landfill settlement very well. Furthermore, the average parameter values from nonlinear regression analyses for 20 instruments exhibited small deviations between calculated and observed settlements, indicating that a single set of parameter values can provide reasonably good representation of all the waste in the vicinity of the test fill. Recommendations for applying the model to other landfills are provided. [ABSTRACT FROM AUTHOR]

We measured sap flux in Pinus ponderosa Laws. and Pinus flexilis James trees in a high-elevation meadow in northern Arizona that has been invaded by conifers over the last 150 years. Sap flux and environmental data were collected from July 1 to September 1, 2000, and used to estimate leaf specific transpiration rate (El), canopy conductance (Gc) and whole-plant hydraulic conductance (Kh). Leaf area to sapwood area ratio (LA/SA) increased with increasing tree size in P. flexilis, but decreased with increasing tree size in P. ponderosa. Both Gc and Kh decreased with increasing tree size in P. flexilis, and showed no clear trends with tree size in P. ponderosa. For both species, Gc was lower in the summer dry season than in the summer rainy season, but El did not change between wet and dry summer seasons. Midday water potential (Ψmid) did not change across seasons for either species, whereas predawn water potential (Ψpre) tracked variation in soil water content across seasons. Pinus flexilis showed greater stomatal response to vapor pressure deficit (VPD) and maintained higher Ψmid than P. ponderosa. Both species showed greater sensitivity to VPD at high photosynthetically active radiation (PAR; > 2500 μmol m−2 s−1) than at low PAR (< 2500 μmol m−2 s−1). We conclude that the direction of change in Gc and Kh with increasing tree size differed between co-occurring Pinus species, and was influenced by changes in LA/SA. Whole-tree water use and El were similar between wet and dry summer seasons, possibly because of tight stomatal control over water loss. [ABSTRACT FROM PUBLISHER]

Aim: To compare the accuracy of MR-determined cerebral blood volume (CBV) maps with SPECT imaging with thallium-201 in pre-operative grading of intracranial glioma.Material and Methods: Nineteen patients (7 female and 12 male, mean age 46.8 years) with intracranial gliomas were examined with MR perfusion imaging pre-operatively. Sixteen of these patients were also examined with SPECT imaging with thallium-201. The tumour to contralateral white matter NI (negative integral) and tracer uptake ratios were evaluated. The ratios in high-grade and low-grade tumours were compared.Results: The maximum CBV ratios of grades I and II gliomas (2.958+/-2.217) were significantly lower than the maximum CBV ratio of grades III and IV (9.484+/-4.520), p<0.001. There was no statistical difference when CBV ratios of grades I and II (p=0.381), grades II and III (p=0.229) and grades III and IV (p=0.476) gliomas were compared. Thallium SPECT imaging showed no difference in tumour uptake ratio between low-grade and high-grade gliomas (p=0.299).Conclusion: MR-determined NI was useful for pre-operative grading of intracranial gliomas but SPECT thallium-201 imaging was not. [ABSTRACT FROM AUTHOR]

Met-Lys-human proinsulin could be converted into insulin in vitro with the treatment of trypsin and carboxypeptides B (CPB). Under less effective conditions, the enzymatic reaction does not proceed perfectly, and twomain bands have been identified by native-polyacrylamide gel electrophoresis (PAGE) analysis. These two main products were thus separated and purified by DEAE-Sephadex A25 chromatography in a Tris-isopropanol system with an NaCl gradient. The isopropanol and NaCl were removed by a second DEAE-Sephadex column. Native-PAGE, mass spectrometric, and amino acid composition analyses indicate that one fraction of these two major products contains human insulin and des B30-insulin and that the other fraction is a mixture of human insulin analogs, which have one more basic amino acid than human in sulin owing to the unsuitable amount of proteases, especially the lack of CPB. Furthermore, both receptor binding assay and radioimmunoassay have been utilized for the activity determination, and both fractions display almost full biological activity with porcine insulin as the standard. Present results provide further evidence for the quality control of recombinant human insulin production. [ABSTRACT FROM AUTHOR]

There is an increasing interest in image registration for a variety of medical imaging applications. Image registration is achieved through the use of a co-ordinate transfer function (CTF) which maps voxels in one image to voxels in the other image, including in the general case changes in mapped voxel intensity. If images of the same subject are to be registered the coordinate transfer function needs to implement a spatial transformation consisting of a displacement and a rigid rotation. In order to achieve registration a common approach is to choose a suitable quality-of-registration measure and devise a method for the efficient generation of the parameters of the CTF which minimize this measure. For registration of images from different subjects more complex transforms are required. In general function minimization is too slow to allow the use of CTFs with more than a small number of parameters. However, provided the images are from the same modality and the CTF can be expanded in terms of an appropriate set of basis functions this paper will show how relatively complex CTFs can be used for registration. The use of increasingly complex CTFs to minimize the within group standard deviation of a set of normal single photon emission tomography brain images is used to demonstrate the improved registration of images from different subjects using CTFs of increasing complexity. [ABSTRACT FROM AUTHOR]

- Forty patients with testicular hydroceles and 16 patients with epididymal cysts were treated by tapping and injection of ethanolamine oleate; 97.5% of the hydroceles and 31% of the epididymal cysts were completely cured, 50% of the latter partly cured and 19% failed. About half of the patients experienced pain after treatment. Two patients developed infection. Ultrasonography showed no change in the testicular tissue during the follow-up period. Sclerotherapy with ethanolamine oleate is a rapid and cost-effective modality which can be recommended as primary treatment for hydroceles and for unilocular epididymal cysts, especially in elderly males. [ABSTRACT FROM AUTHOR]

We examined 21 patients aged 5 months to 19 years, on a 1.5 T magnet. T1-weighted spin-echo images, proton density and T2-weighted images with spin-echo and turbo spin-echo sequences, and contrast-enhanced magnetization transfer (MT) T1-weighted images were obtained in all cases. MT T1-weighted images were performed before injection in 9 patients. Subependymal nodules were found in 14, and cortical and subcortical tubers in 20 of the 21 patients. MT T1-weighted images showed tubers and subependymal nodules as higher signal than normal gray matter and revealed more tubers than conventional sequences in 11 cases. High signal intensity lesions of the white matter were found in 19 patients but were seen only on MT images in 9 cases. When MT images both before and after injection were available, tubers and white matter lesions were more easily recognised on unenhanced MT images because of their higher contrast. [ABSTRACT FROM AUTHOR]

We evaluated the effect of dipyridamole on thallium-201 myocardial perfusion in 23 patients with progressive systemic sclerosis (PSS) with diffuse scleroderma. Thallium-201 single photon emission computed tomography (SPECT) was performed at rest and after coronary artery vasodilatation with intravenous dipyridamole (0.14 mg/kg/min for four minutes). The left myocardium was divided into nine segments; each segment was graded as 2.0, 1.5, 1.0, 0.5, 0 (zero represents no activity). Dipyridamole significantly improved resting thallium-201 myocardial perfusion: the mean (SD) number of segments with thallium defects decreased from 6.0 (2.1) at rest to 4.1 (2.5) after dipyridamole (p less than 0.0001); the mean (SD) score in segments with resting defects increased from 0.92 (0.24) at rest to 1.13 (0.38) after dipyridamole (p less than 0.0001); the mean (SD) global score per patient increased from 10.2 (1.8) at rest to 11.4 (2.1) after dipyridamole (p less than 0.02); the global score increased by at least 2.0 in 12 patients and worsened by at least 2.0 in three patients only (p = 0.05). The results of this acute study suggest that some drugs with potent vasodilator activity on small coronary arteries may be beneficial in the treatment of PSS patients with thallium-201 myocardial perfusion abnormalities. [ABSTRACT FROM PUBLISHER]