The effect of formulation on radioiodide thyroid uptake in the hyperthyroid cat

This investigation was designed to compare in vitro dissolution profiles from sodium iodide capsules with radioiodide thyroid uptake in hyperthyroid cats using sodium iodide capsules prepared with a formulation exhibiting a complete release of radioiodide (I-123) in vitro and a formulation with an incomplete release of radioiodide. In vitro dissolution profiles for I-123 sodium iodide capsules with two different formulations were determined using the USP XXIII dissolution test. The two formulations studied in vitro were sodium phosphate dibasic powder with 1% magnesium stearate and calcium phosphate dibasic powder with 3% magnesium stearate. By 20 min after initiation of the dissolution test, over 95% of the I-123 was released from capsules of sodium phosphate dibasic powder. The capsules of calcium phosphate dibasic powder reached 75% at 65 min, with no further release occurring thereafter. There was a statistically significant difference in the dissolution profiles of the two formulations. The thyroid uptake of I-123 from capsules exhibiting complete release and incomplete release of radioiodide was determined in hyperthyroid cats. At 4 hr, the mean percentage thyroid uptake value for sodium phosphate dibasic powder with 1% magnesium stearate (complete release formulation) was 12.0% compared to 9.4% for calcium phosphate dibasic powder with 3% magnesium stearate (incomplete release formulation); at 24 hr, the values were 34.4% compared to 23.7%. The data suggest that the incomplete dissolution profile observed in vitro may correlate with a reduction in the bioavailability of the radioiodide in vivo. However, using the Wilcoxon signed rank test, statistically significant differences did not occur between the complete release formulation and incomplete release formulation at either 4 hr or 24 hr (p > .05). The results of the in vivo study with five hyperthyroid cats were not conclusive due to the variability in response between individual cats.     

Spatial analysis of annual air pollution exposure and mortality

The aim of this study was to relate ambient air pollution levels to mortality in Auckland, New Zealand. We used urban airshed modelling and GIS-based techniques to quantify long-term exposure to ambient air pollution levels and associated mortality. After adjusting for age, sex, ethnicity, socio-economic status, and urban/rural domicile there was a 1.3% (95%CI: 1-1.5%) increase in non-external cause mortality, and 1.8% (95%CI: 1.5-2.1%) increase in circulatory and respiratory causes per 1 microg/m(3) increase in annual average NO(2). Based on these exposure-response relationships and applying an annual average threshold of 13 microg/m(3), the average annual (for 1996-1999) number of people estimated to die from non-external causes and circulatory and respiratory causes attributable to air pollution in Auckland is 268 (95% range: 227-310) (3.9% of total all cause deaths) and 203 (95% range: 169-237) (5.9% of total circulatory and respiratory deaths) per year, respectively. The number of attributable deaths found in this study are consistent with a previous New Zealand risk assessment using a different methodology, and is approximately twice the number of people dying from motor vehicle accidents in the region, which is on average (1996-1999) 103 per year. The GIS-based exposure maps identify high exposure areas for policy developers and planners in a simple and realistic manner. Taken together with overseas studies the study provides additional evidence that long-term exposure to poor air quality, even at levels below current standards, is a hazard to the public health.     

Effect of load position on physiological and perceptual responses during load carriage with an internal frame backpack

The purpose of this study was to determine the effect of load position in an internal frame backpack on physiological and perceptual variables. Ten female participants walked on a level treadmill for 10 min carrying 25% of their body weight in a high, central, or low position. The variables measured included oxygen consumption (VO2), heart rate (HR), respiratory exchange ratio (R), respiratory rate (RR), minute ventilation (VE), and rating of perceived exertion (RPE). VO2, VE, and RPE were significantly lower in the high position (18.6 +/- 2.3 ml/kg/min, 31.7 +/- 5.0 l/min, 2.8 +/- 0.8, respectively) compared to the low position (22.2 +/- 3.0 ml/kg/min, 38.6 +/- 7.5 l/min, 3.7 +/- 1.0, respectively). HR, R, and RR did not change significantly as the load was moved from the high (129.8 +/- 16.8, 0.89 +/- 0.06, 30.3 +/- 4.2, respectively) to the low position (136.0 +/- 25.3, 0.92 +/- 0.04, 33.8 +/- 5.2, respectively). The results of this study suggest that load placement is an important factor in the physiological and perceptual responses to load carriage, and that packing heavy items high in the backpack may be the most energy efficient method of carrying a load on the back.     

Design and performance of a roof integrated solar air heater

This paper discusses the design and construction of a roof integrated solar air heater used in a space heating system for a well insulated house located in Melbourne, Australia. The design of the house and the heat storage system is not discussed and details may be obtained elswhere [1]. The space heating system consists of an array of solar air heaters coupled to a rockbed thermal store located under the floor of the house, such that the rooms are heated by radiation and convection from the floor.     

Differential Scanning Calorimetry of Aspartame-Caffeine Mixture

The possible interaction between aspartame and caffeine was investigated by comparing the thermal behavior, using differential scanning calorimetry, of physical mixtures of aspartame and caffeine along with mixtures, in the same molar ratios, obtained as the co-precipitate. Caffeine was found to form several complexes with aspartame. These complexes were found to be dependent on the molar ratios of aspartame to caffeine. The stoichiometry of the aspartame-caffeine complexes were determined from the enthalpy change of the DSC transitions resulting from the complex formation.     

Physical properties and molecular behavior of chitosan films

Chitosan films, varying in molecular weight and degree of deacetylation, were prepared by a casting technique using acetic acid as a dissolving vehicle. The physicochemical properties of the films were characterized. Both molecular weight and degree of deacetylation affected the film properties. Powder X-ray diffraction patterns and differential scanning calorimetry thermograms of all chitosan films indicated their amorphous state to partially crystalline state with thermal degradation temperature lower than 280-300°C. The increase in molecular weight of chitosan would increase the tensile strength and elongation as well as moisture absorption of the films, whereas the increase in degree of deacetylation of chitosan would either increase or decrease the tensile strength of the films depending on its molecular weight. Moreover, the higher the degree of deacetylation of chitosan the more brittle and the less moisture absorption the films became. All chitosan films were soluble in HCl-KCl buffer (pH 1.2), normal saline, and distilled water. They swelled in phosphate buffer (pH 7.4), and cross-linking between chitosan and phosphate anions might occur. Finally, transmission infrared and ¹³C-NMR spectra supported that chitosan films prepared by using acetic acid as a dissolving were chitosonium acetate films.     

Movement abnormalities and the progression of prodromal symptomatology in adolescents at risk for psychotic disorders.

The link between movement abnormalities and psychotic disorders is presumed to reflect common neural mechanisms that influence both motor functions and vulnerability to psychosis. The prodromal period leading to psychotic disorders represents both a viable point for intervention and a developmental period that, if studied, could shed light on etiology; however, no published studies have examined the temporal progression of this link. A group with high levels of prodromal symptomatology (i.e., adolescents with schizotypal personality disorder [SPD]; n = 42) and both psychiatric controls (with other personality disorders or conduct disorder [OD]; n = 30) and nonpsychiatric controls ([NC]; n = 49) were recruited. Videotapes of structured psychiatric interviews were coded for movement abnormalities by raters blind to participants' diagnostic status, and follow-up assessments were conducted 1 year later. Controlling for psychotropic medications, the authors found that adolescents with SPD exhibited significantly more motor abnormalities in the face and upper body than did OD and NC controls. At baseline, movement abnormalities were positively correlated with the severity of positive, negative, and total prodromal symptoms. Within the SPD group, baseline movement abnormalities predicted symptom severity 1 year later. Movement abnormalities represent an early risk indicator that may be predictive of later symptom severity and potentially of psychosis onset. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Gender differences in mediated communication: Women connect more than do men

Past research in gender differences in the overall Internet use has been contradictory. Some asserted men used it more than women, while others asserted there were no gender difference. Both camps concluded that men and women differed in their motivation and utilization of time spent online. The purpose of the present research was to take a contemporary look at these gender differences. Using an online survey, we asked participants about their experiences with multiple forms of mediated communication: social networking sites, e-mail, video calls, instant messaging, texting, and phone calls. Our results indicated that women, compared to men, are generally more frequent mediated communication users. Compared to men, women prefer and more frequently use text messaging, social media, and online video calls. These results suggest that the nature of mediated social interaction is changing.     

Accessibility and interoperability in e-government systems: outlining an inclusive development process

The multidisciplinary nature of e-government demands a research agenda that includes issues related to social inclusion, universal accessibility, interoperability, privacy, security, and citizen participation, to name a few. Understanding the underlying cultural context, the involvement of citizens in the proposal and evaluation of services, and the promotion of quality in use are aspects that need special consideration in the development of systems to support government. This paper provides an outline for a process model for promoting the identification and specification of accessible e-government services with the participation of the interested parties. A socially shared perspective is adopted toward the comprehension of the involved problems and the elaboration of potential solutions. The proposed model is a result of practice in the domain, using organizational semiotics artifacts to stimulate participation and discussion.