Auditory Categorization of Complex Sounds by Rats (Rattus norvegicus).

Little research has explored the auditory categorization abilities of mammals. To better understand these processes, the authors tested the abilities of rats (Rattus norvegicus) to categorize multidimensional acoustic stimuli by using a classic category-learning task developed by R. N. Shepard, C. I. Hovland, and H. M. Jenkins (1961). Rats proved to be able to categorize 8 complex sounds on the basis of either the direction or rate of frequency modulation but not on the basis of the range of frequency modulation. Rats' categorization abilities were limited but improved slowly and incrementally, suggesting that learning was not facilitated by selective attention to acoustic dimensions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Profile of a population using a primary health care center in Puerto Rico

PURPOSE: To describe the services delivered by the Family Medicine Physicians at a Community Health Center. METHODS: All information from patient visits during the natural year 1996 were registered using a commercialized computer program. The information was gathered by different means: initial interview, physician's report, records, and personal interviews. RESULTS: A total of 13,203 visits were registered; this represent a total of 4,493 patients. Most of the patients were women, and with a mean age of 38. As expected, most of the patients have Medicaid. The most common conditions seen were hypertension, diabetes, and respiratory diseases. The mean number of visits during the year for almost all conditions was three. Most of the children and adolescents visit the Center due to respiratory conditions, while adults come due to hypertension, diabetes, and musculoskeletal conditions.     

Nephrotic syndrome in autosomal dominant polycystic kidney disease

Urinary protein excretion is generally less than 1 g/24 h in autosomal dominant polycystic kidney disease (ADPKD), and the association of the nephrotic syndrome with this condition is considered rare. A patient with ADPKD associated with nephrotic-range proteinuria is described. She exhibited a relatively rapid impairment of her renal function. An open renal biopsy revealed focal segmental glomerulosclerosis (FGS) with features consistent with secondary FGS. Twenty-one patients with ADPKD and nephrotic syndrome were retrieved from the literature. Fourteen of them (including this case) had a histopathologic evaluation, and FGS was the dominant diagnoses (five patients). Next in frequency were minimal-change disease and membranous nephropathy, with two patients each. Five other patients had a variety of diagnoses. Thus, it is difficult to ascertain if these associations are coincidental or represent a specific pathogenetic relationship. The evaluation of the data also suggests that the presence of proteinuria and nephrotic syndrome accelerates the course of ADPKD toward ESRD.     

DEVELOPMENT OF AN X-RAY FLUORESCENCE SPECTROMETER FOR ENVIRONMENTAL SCIENCE APPLICATIONS

The performance of a new X-ray spectrometer is presented. The device was designed originally to be employed in environmental sciences, and allows the use of different types of primary radiation sources, such as a radioactive source (²⁴¹Am) or tubes with anodes of different metals (Rh or W). Among the advantages of this spectrometer are the possibility of exchanging detectors to improve efficiency at different X-ray energy ranges [such as Si (Li), Si-PIN, hyperpure Ge, or CdTe detectors], to attach it to a wavelength dispersive system, and its use in vacuum or atmospheric pressure. Furthermore, it is feasible to modify the geometry so a secondary target may be installed for using polarized X-rays as exciting radiation.     

On the Analysis of Balanced Two‐Level Factorial Whole‐Plot Saturated Split‐Plot Designs

This paper considers an experimentation strategy when resource constraints permit only a single design replicate per time interval and one or more design variables are hard to change. The experimental designs considered are two‐level full‐factorial or fractional‐factorial designs run as balanced split plots. These designs are common in practice and appropriate for fitting a main‐effects‐plus‐interactions model, while minimizing the number of times the whole‐plot treatment combination is changed. Depending on the postulated model, single replicates of these designs can result in the inability to estimate error at the whole‐plot level, suggesting that formal statistical hypothesis testing on the whole‐plot effects is not possible. We refer to these designs as balanced two‐level whole‐plot saturated split‐plot designs. In this paper, we show that, for these designs, it is appropriate to use ordinary least squares to analyze the subplot factor effects at the ‘intermittent’ stage of the experiments (i.e., after a single design replicate is run); however, formal inference on the whole‐plot effects may or may not be possible at this point. We exploit the sensitivity of ordinary least squares in detecting whole‐plot effects in a split‐plot design and propose a data‐based strategy for determining whether to run an additional replicate following the intermittent analysis or whether to simply reduce the model at the whole‐plot level to facilitate testing. The performance of the proposed strategy is assessed using Monte Carlo simulation. The method is then illustrated using wind tunnel test data obtained from a NASCAR Winston Cup Chevrolet Monte Carlo stock car. Copyright © 2012 John Wiley & Sons, Ltd.     

Laminated antiferromagnetically coupled media - optimization and extendibility

Lamination of multiple isolated magnetic layers has been shown to be an effective method to significantly increase signal-to-noise ratio in longitudinal media. These laminated media, however, are accompanied by low overwrite and wide magnetic pulse width, mainly as a result of poor writing of the bit transitions in the magnetic layer further away from the head and an offset in the transition position in the multiple magnetic layers resulting from head field spacing loss. We have demonstrated that the transition writing and transition alignment in the multiple magnetic layers of the laminated antiferromagnetically coupled (AFC) media can be optimized by adjusting the magnetic anisotropy of the relevant magnetic layers to compensate for the reduction of the head field magnitude with spacing. Such optimization results in significant improvements in media recording performance, leading to successful application of this medium technology. In this paper, we will highlight some of these improvements and discuss our approaches to further improve the recording performance by reducing the thicknesses of the magnetic layers and the lamination spacer layer in the laminated AFC film stack and by introducing additional elements in the magnetic layer.     

Coping with neck and low back pain in the general population.

This study had 2 objectives: (a) to assess the psychometric properties of the Pain Management Inventory (PMI; G. K. Brown & P. M. Nicassio, 1987) with individuals in the general population with neck or low back pain, and (b) to assess the relationship between pain severity and coping. Data were taken from a mailed survey of a random sample of adults residing in Saskatchewan, Canada. Results validated the 2-factor structure of the PMI and provided evidence for the internal consistency of the coping subscales. Regression analyses revealed that passive coping was associated with being married, greater pain severity, depression, and poor health. Active coping was associated with female gender, higher education, less depression, good health, and frequent exercise. This study provides psychometric data to support the use of the PMI and information about factors associated with use of active and passive coping strategies in pain sufferers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Viscosity reduction of heavy crude oil by dilution with hydrocarbons obtained via chemical recycling of plastic wastes

The increasing energy demand is persuading oil companies to exploit unconventional reserves of heavy and extra heavy crude oil, which are characterized for their elevated viscosities and upraised production costs. Expensive flow modifiers are often used to lower the viscosity of heavy crude oils so that pipeline transportation becomes viable. In this study, thermal cracking tests were conducted to obtain hydrocarbons (condensate) of lower molar masses, from common plastic wastes. Physical properties of the products were measured, such as viscosity, density, pour point, cloud point and aniline temperature. Due to their chemical similarity, the hydrocarbon products from the tertiary recycling of postconsumer low density polyethylene (LDPE) plastic bags were used to dilute a heavy crude oil (12°API) and lower its viscosity. Results showed a viscosity reduction of 90% at room temperature of a 5:25 vol:vol blend of hydrocarbons/heavy crude oil. This paper proposes an alternative solution for two alarming global problems: waste plastics recovery and optimal transportation of heavy crude oil; However, an industrial application of this process would have to be combined with municipal solid waste collection and pre-treatment technologies.