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Physical Differences (physical + difference)
Selected AbstractsCharacterization of ultrasound extrudated and cut citric acid/paracetamol blendsJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 6 2009P. Hoppu Abstract The purpose of the present work was to study the effect of ultrasound extrusion and cutting on the physical stability of a viscous and sticky supercooled melt containing (50/50, w/w, %) citric acid anhydrate and paracetamol. Samples were extrudated at temperatures of 50, 60, and 70°C using power levels of 0, 50, 100, and 150 W. Similarly, extrudates prepared at 60°C were cut at temperatures ranging from 25,60°C with an ultrasound knife in the range 0, 50, and 100 W. The characterization methods used were: high performance liquid chromatography, differential scanning calorimetry, Karl Fischer titration, X-ray powder diffraction, Fourier transform infrared microscopy, optical- and stereomicroscopy. There was no physical difference in extrudates or cut surfaces whether processed with or without ultrasound. During 1-year aging time in dry conditions, all the samples were observed to crystallize slowly and ultrasound processing did not enhance the crystallization. Ultrasound thus holds some promise for processing of viscous and sticky pharmaceuticals, provided the material is physically stable enough to withstand mechanical and thermal stress. Processing of sticky and viscous material would be difficult without ultrasound with the methods currently used in pharmaceutical industry. © 2008 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:2140,2148, 2009 [source] The representation of Kanizsa illusory contours in the monkey inferior temporal cortexEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 10 2008Gy. Sáry Abstract Stimulus reduction is an effective way to study visual performance. Cues such as surface characteristics, colour and inner lines can be removed from stimuli, revealing how the change affects recognition and neural processing. An extreme reduction is the removal of the very stimulus, defining it with illusory lines. Perceived boundaries without physical differences between shape and background are called illusory (or subjective) contours. Illusory and real contours activate early stages of the macaque visual pathway in similar ways. However, data relating to the processing of illusory contours in higher visual areas are scarce. We recently reported how illusory contours based on abutting-line gratings affect neurones in the monkey inferotemporal cortex, an area essential for object and shape vision. We now present data on how inferotemporal cortical neurones of monkeys react to another type of shapes, the Kanizsa figures. A set of line drawings, silhouettes, their illusory contour-based counterparts, and control shapes have been presented to awake, fixating rhesus monkeys while single-cell activity was recorded in the anterior part of the inferotemporal cortex. Most of the recorded neurones were responsive and selective to shapes presented as illusory contours. Shape selectivity was proved to be different for line drawings and illusory contours, and also for silhouettes and illusory contours. Neuronal response latencies for Kanizsa figures were significantly longer than those for line drawings and silhouettes. These results reveal differences in processing for Kanizsa figures and shapes having real contours in the monkey inferotemporal cortex. [source] Fatty acid analyses reveal high degrees of omnivory and dietary plasticity in pond-dwelling tadpolesFRESHWATER BIOLOGY, Issue 7 2010MATT R. WHILES Summary 1.,Understanding the trophic relationships of consumers is central to ecology, but constructing meaningful food webs is often difficult because of a lack of detailed information on consumption versus assimilation and high degrees of omnivory. 2.,We used fatty acid analyses to examine the trophic relationships of three common larval anurans (Pseudacris crucifer, Lithobates catesbeianus and Lithobates clamitans) that are often classified as grazers or detritivores. Tadpoles and potential food sources were sampled in four ponds in southern Illinois and analysed for fatty acid composition. Single linkage cluster analysis was then used to compare fatty acid profiles among tadpole gut contents, tadpole muscle tissues and available food resources. 3.,Diets varied among species and within species among ponds, but organic sediments consistently contributed most to the fatty acid composition of the gut contents of all species. Fatty acid profiles also indicated that larval insects and phytoplankton were consumed by both L. catesbeianus and L. clamitans in one pond, while L. clamitans and P. crucifer consumed mainly periphyton along with sediments in another pond, and these diet differences appeared linked to physical differences among ponds, with periphyton and/or phytoplankton contributing more to tadpole diets in less shaded ponds. 4.,The fatty acid composition of muscle tissues of L. clamitans, the dominant tadpole in these systems, indicated that plant detritus and bacteria, which were the dominant components of organic sediments in the ponds, were common components of the assimilatory diet. 5.,Results demonstrate the utility of fatty acid analyses for assessing both consumption and assimilation. The tadpole assemblages we examined derive much of their energy from heterotrophic and allochthonous sources and exhibit high dietary plasticity. This information will allow for more accurate and comprehensive assessments of trophic interactions in freshwater habitats, as well as aid in amphibian conservation, management and captive propagation efforts. [source] Tuning Conversion Efficiency in Metallo Endohedral Fullerene-Based Organic Photovoltaic DevicesADVANCED FUNCTIONAL MATERIALS, Issue 14 2009Russel B. Ross Abstract Here the influence that 1-(3-hexoxycarbonyl)propyl-1-phenyl-[6,6]-Lu3N@C81, Lu3N@C80,PCBH, a novel acceptor material, has on active layer morphology and the performance of organic photovoltaic (OPV) devices using this material is reported. Polymer/fullerene blend films with poly(3-hexylthiophene), P3HT, donor material and Lu3N@C80,PCBH acceptor material are studied using absorption spectroscopy, grazing incident X-ray diffraction and photocurrent spectra of photovoltaic devices. Due to a smaller molecular orbital offset the OPV devices built with Lu3N@C80,PCBH display increased open circuit voltage over empty cage fullerene acceptors. The photovoltaic performance of these metallo endohedral fullerene blend films is found to be highly impacted by the fullerene loading. The results indicate that the optimized blend ratio in a P3HT matrix differs from a molecular equivalent of an optimized P3HT/[6,6]-phenyl-C61 -butyric methyl ester, C60,PCBM, active layer, and this is related to the physical differences of the C80 fullerene. The influence that active layer annealing has on the OPV performance is further evaluated. Through properly matching the film processing and the donor/acceptor ratio, devices with power conversion efficiency greater than 4% are demonstrated. [source] Heat-induced Changes in Angel Food Cakes Containing Egg-white Protein or Whey Protein IsolateJOURNAL OF FOOD SCIENCE, Issue 8 2002C.W. Pernell ABSTRACT: Angel food cakes made from egg white or whey protein foams were compared. Cakes were evaluated based on final volume, dynamic volume change, and rheological transitions during baking. Cake expansion during baking was a function of protein concentration regardless of protein type. Cakes containing whey proteins had a lower ability to prevent collapse once starch gelatinization started during baking. Heat-treating whey proteins or adding xanthan gum increases cake volume, but not to the extent of egg-white proteins. Cakes containing egg-white proteins became more elastic at 60 to 85 °C than those containing whey proteins, indicating physical differences in the heat-set protein foam network associated with protein type. [source] The Characterization of Automobile Body Fillers,JOURNAL OF FORENSIC SCIENCES, Issue 1 2008Sara C. McNorton M.S. Abstract:, Body fillers are sometimes encountered with paint evidence from hit-and-run accidents. Little forensic research has been conducted and published on the subject since 1986. The objective of this study was to determine if chemical and physical differences in body fillers from various manufacturers existed and could be identified. Thirty-three samples of light-weight automobile body fillers and spot putties were obtained. The fillers and putties were compared using light microscopy, infrared spectroscopy, scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDX), and pyrolysis gas chromatography (pyGC). Results from fourier transform infrared spectroscopy analysis placed the samples into five groups and differentiated six samples. Light microscopy placed the samples into one of five color groups. PyGC placed the samples into three groups and differentiated one sample. SEM-EDX placed the samples into four groups and differentiated 13 samples. Using these analysis methods, 19 of the 33 samples could be discriminated. The best discriminatory tool was found to be SEM-EDX. [source] Aggregated structure of flocculated asphaltenesAICHE JOURNAL, Issue 1 2001Theophylaktos G. Savvidis Many petroleum processing problems are related to asphaltene flocculation. A detailed understanding of the colloidal structure of asphaltenes in oild can play a decisive role in improving processing facilities and/or operating conditions. The structure of the flocculated part of the asphaltenes of a crude oil far above the flocculation threshold was studied to understand its links with macroscopic phase separation. Asphaltene filtrations were performed using filter pore sizes from 0.025 to 10 ,m. According to small angle X-ray scattering (SAXS) spectra and density measurements, these extracted asphaltenes in toluene solutions did not have any physical differences. Measurements of nanometric sizes for the dispersed particles after dissolution in toluene show that micron-size flocculated asphaltenes are strongly aggregated structures. Therefore, filtration experiments separate asphaltenes corresponding powders show spherically shaped aggregates of micron size. SAXS and USAXS techniques were used to investigate the internal structure of the asphaltene powder. The aggregates are clearly a compact organization of asphaltenic material. This dense structure explains why flocculated asphaltenes are subject to sedimentation, which induces the visible macroscopic phase separation. [source] Stigma, Community, Ethnography: Joan Ablon's Contribution to the Anthropology of Impairment-DisabilityMEDICAL ANTHROPOLOGY QUARTERLY, Issue 2 2004RUSSELL P. SHUTTLEWORTH Joan Ablon has helped establish the anthropology of impairment-disability and significantly contributed to the role of anthropology in disability studies. In this article, we review the development of and situate Ablon's ethnographic research in the anthropology of impairment-disability. We then address various methodological issues in her work including her ethnographic approach, her grounding in action anthropology and her support for the development of the academic study of disability in anthropology and the careers of disabled anthropologists. The next section of the article examines Ablon's use of the notion of stigma, her understanding of community, and her engagement with disability rights. As examples of themes important to disability studies, we present her discussion of the implications of the ideal of the body beautiful, and gender differences in negotiating intimacy for people with physical differences. We close with a discussion of the future of an anthropology of impairment-disability. [disability, impairment, Ablon, genetics, ethnography] [source] ISO observations of 3,200 ,m emission by three dust populations in an isolated local translucent cloudMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 3 2005M. G. Rawlings ABSTRACT We present isophot spectrophotometry of three positions within the isolated high-latitude cirrus cloud G 300.2,16.8, spanning from the near- to far-infrared (NIR to FIR). The positions exhibit contrasting emission spectrum contributions from the unidentified infrared bands (UIBs), very small grains (VSGs) and large classical grains, and both semi-empirical and numerical models are presented. At all three positions, the UIB spectrum shapes are found to be similar and the large grain emission may be fitted by an equilibrium temperature of ,17.5 K. The energy requirements of both the observed emission spectrum and optical scattered light are shown to be satisfied by the incident local interstellar radiation field (ISRF). The FIR emissivity of dust in G 300.2,16.8 is found to be lower than in globules or dense clouds and is even lower than model predictions for dust in the diffuse interstellar medium (ISM). The results suggest physical differences in the ISM mixtures between positions within the cloud, possibly arising from grain coagulation processes. [source] The physical characteristics and usage patterns of stone axe and pounding hammers used by long-tailed macaques in the Andaman Sea region of ThailandAMERICAN JOURNAL OF PRIMATOLOGY, Issue 7 2009Michael D. Gumert Abstract Stone hammering in natural conditions has been extensively investigated in chimpanzees and bearded capuchins. In contrast, knowledge of stone tool use in wild Old World monkeys has been limited to anecdotal reports, despite having known for over 120 years that Macaca fascicularis aurea use stone tools to process shelled foods from intertidal zones on islands in the Andaman Sea. Our report is the first scientific investigation to look at the stone tools used by these macaques. We observed they were skilled tool users and used stone tools daily. They selected tools with differing qualities for differing food items, and appeared to use at least two types of stone tools. Pounding hammers were used to crush shellfish and nuts on anvils and axe hammers were used to pick or chip at oysters attached to boulders or trees. We found significant physical differences between these two tools. Tools at oyster beds were smaller and exhibited scarring patterns focused more often on the points, whereas tools found at anvils were larger and showed more scarring on the broader surfaces. We also observed grip differences between the two tool types. Lastly, macaques struck targets with axe hammers more rapidly and over a wider range of motion than with pounding hammers. Both our behavioral and lithic data support that axe hammers might be used with greater control and precision than pounding hammers. Hand-sized axe hammers were used for controlled chipping to crack attached oysters, and larger pounding hammers were used to crush nuts and unattached shellfish on anvils. In addition to stones, they also used hand-sized auger shells (Turritella attenuata) as picks to axe attached oysters. Pound hammering appears similar to the stone tools used by chimpanzees and capuchins, but axe hammering has not yet been documented in other nonhuman primates in natural conditions. Am. J. Primatol. 71:594,608, 2009. © 2009 Wiley-Liss, Inc. [source] A clinical, cytogenetic and molecular study of 47 females with r(X) chromosomesANNALS OF HUMAN GENETICS, Issue 4 2000N. DENNIS We studied 47 patients with a 45,X/46,X,r(X) karyotype to identify phenotypic differences between these patients and 45,X patients, and to determine whether these differences could be explained by the status of genes within the ring. Only 2 patients had the ,severe' r(X) phenotype, and both were consistent with this resulting from functional disomy of genes normally subject to X inactivation. A further 7 patients also carried active rings but these patients did not have a more severe phenotype than those whose rings were inactivated, probably because their rings were smaller and did not contain the (as yet unidentified) genes whose functional disomy is particularly damaging. Patients with a r(X) did not show clear physical differences when compared with a 45,X series, except for a possible reduction in the frequency of oedema in those whose r(X) had an Xq breakpoint distal to DXS128E, at Xq13.2. Thus some protection from oedema may be provided by the presence of two copies of Xq13.2. [source] | |||||||||||||