An "openable," high-strength gradient set for orthopedic MRI

A novel three-axis gradient set and RF resonator for orthopedic MRT has been designed and constructed. The set is openable and may be wrapped around injured joints. The design methodology used was the minimization of magnetic field spherical harmonics by simulated annealing. Splitting of the longitudinal coil presents the major design challenge to a fully openable gradient set and in order to efficiently design such coils, we have developed a new fast algorithm for determining the magnetic field spherical harmonics generated by an are of multiturn wire. The algorithm allows a realistic impression of the effect of split longitudinal designs. A prototype set was constructed based on the new designs and tested in a 2-T clinical research system. The set generated 12 mT/m/A with a linear region of 12 cm and a switching time of 100 mu s, conforming closely with theoretical predictions. Preliminary images from the set are presented. (C) 1999 Academic Press.

Designs for an asymmetric gradient set and a compact superconducting magnet for neural magnetic resonance imaging

Imaging of the head and neck is the most commonly performed clinical magnetic resonance imaging (MRI) examination [R. G. Evans and J. R. G. Evans, AJR 157, 603 (1991)]. This is usually undertaken in a generalist MRI instrument containing superconducting magnet system capable of imaging all organs. These generalist instruments are large, typically having a bore of 0.9-1.0 m and a length of 1.7-2.5 m and therefore are expensive to site, somewhat claustrophobic to the patient, and offer little access by attending physicians. In this article, we present the design of a compact, superconducting MRI magnet for head and neck imaging that is less than 0.8 m in length and discuss in detail the design of an asymmetric gradient coil set, tailored to the magnet profile. In particular, the introduction of a radio-frequency FM modulation scheme in concert with a gradient sequence allows the epoch of the linear region of the gradient set to be much closer to the end of the gradient structure than was previously possible. Images from a prototype gradient set demonstrate the effectiveness of the designs. (C) 1999 American Institute of Physics. [S0034-6748(99)04910-2].

Dental set-vice provision in private general practice for an insured population in New South Wales, Australia

Objective To determine patterns of dental set-vices provided to a cohort of the insured population 18 years and over, in private general practice in New South Wales, Australia. Basic research design A cohort study using the person-years method and Poisson regression for analysis. Setting Data were derived from claims records submitted by members of a health insurance fund (Government Employees Health Fund-GEHF) for rebates during the study period 1 January 1992-31 December 1995. Participants There were 133,467 members aged 18 years and over from New South Wales. Main outcome measures To determine, by age group, for those members who used private general practice and made a claim (referred to as 'patients') the annual number of visits, total number of services received per year and number of services received at a visit, Results The mean number of visits per patient was 2.4 per year with patients under 45 years making fewer visits than the 45-54 age group reference category. Mean number of services utilised per patient-year was 5.9, with services provided increasing from 3.5 for the 18-24-year-old group, reaching a plateau of approximately 6.2 for those aged 45 years or more. The number of services received per visit was 2.4 and there were no differences by age. Service mix was dominated by restorative (35%), diagnostic (27%), and preventive services (18%); with age specific variations observed. Conclusions Age was found to be an important determinant in the use of dental services, independent of membership duration and gender.

Cytokine-related genes identified from the RIKEN full-length mouse cDNA data set

To identify novel cytokine-related genes, we searched the set of 60,770 annotated RIKEN mouse cDNA clones (FANTOM2 clones), using keywords such as cytokine itself or cytokine names (such as interferon, interleukin, epidermal growth factor, fibroblast growth factor, and transforming growth factor). This search produced 108 known cytokines and cytokine-related products such as cytokine receptors, cytokine-associated genes, or their products (enhancers, accessory proteins, cytokine-induced genes). We found 15 clusters of FANTOM2 clones that are candidates for novel cytokine-related genes. These encoded products with strong sequence similarity to guanylate-binding protein (GBP-5), interleukin-1 receptor-associated kinase 2 (IRAK-2), interleukin 20 receptor alpha isoform 3, a member of the interferon-inducible proteins of the Ifi 200 cluster, four members of the membrane-associated family 1-8 of interferon-inducible proteins, one p27-like protein, and a hypothetical protein containing a Toll/Interleukin receptor domain. All four clones representing novel candidates of gene products from the family contain a novel highly conserved cross-species domain. Clones similar to growth factor-related products included transforming growth factor beta-inducible early growth response protein 2 (TIEG-2), TGFbeta-induced factor 2, integrin beta-like 1, latent TGF-binding protein 4S, and FGF receptor 4B. We performed a detailed sequence analysis of the candidate novel genes to elucidate their likely functional properties.

Identification of novel "pathologs" (human disease-related gene candidates) from the RIKEN full-length mouse cDNA data set

The majority of common diseases such as cancer, allergy, diabetes, or heart disease are characterized by complex genetic traits, in which genetic and environmental components contribute to disease susceptibility. Our knowledge of the genetic factors underlying most of such diseases is limited. A major goal in the post-genomic era is to identify and characterize disease susceptibility genes and to use this knowledge for disease treatment and prevention. More than 500 genes are conserved across the invertebrate and vertebrate genomes. Because of gene conservation, various organisms including yeast, fruitfly, zebrafish, rat, and mouse have been used as genetic models.

Adoption of Strategic Alliances by Shoes Industries of the Vale do Rio dos Sinos-RS and Franca-SP clusters: an exploratory study

The new environment of the companies, result of the relative opening of the market caused by the globalization has set a new challenge to assure the continuity of the businesses. Competitive strategies have been implemented aiming to overcome such challenge and, amongst them, strategic alliances have shown to be a viable alternative. In this context, this article has as objective to investigate the degree of use of strategic alliances by the medium and large companies of the shoes industries located in clusters of Vale do Rio dos Sinos (RS) and Franca (SP). This exploratory and descriptive research had the participation of 54 companies, being 3 from Vale do Rio dos Sinos and 21 from Franca, which answered a questionnaire with closed questions. The analysis of the data was given through descriptive statistics. Main conclusions, follow as: (1) the majority of the companies have joint activities; (2) the companies are nearer to alliances that do business than to the strategic ones; (3) alliances with competitors are inexpressive - suppliers and customers predominate; (4) the control of alliances result is insufficient; (5) trust and adequate partner are determinative factors.

Ant visitation to extrafloral nectaries decreases herbivory and increases fruit set in Chamaecrista debilis (Fabaceae) in a Neotropical savanna

Studies of ant-plant relationships elucidate how top-down effects of the third trophic level can affect the biomass, richness, and/or species composition of plants. Although widespread in the neotropics, few studies have so far examined the direct effects of ants on plant fitness. Here, through experimental manipulation (ant-exclusion) under natural conditions, we examined the effect of ant visitation to extrafloral nectaries on leaf herbivory and fruit set in Chamaecrista debilis in the Brazilian savanna. As opposed to other Chamaecrista species, our results showed that visiting ants (15 species) significantly reduce herbivory and increase fruit set by more than 50% compared to plants from which ants were excluded. This mutualistic system is facultative in nature, and corroborates the potential beneficial role of exudate-feeding ants as anti-herbivore agents of tropical plants. (C) 2010 Elsevier GmbH. All rights reserved.

On the construction of integrable closed chains with quantum supersymmetry

We present a general prescription for the construction of integrable one-dimensional systems with closed boundary conditions and quantum supersymmetry.

Hyperplane navigation: A method to set individual scores in fMRI group datasets

Recent studies have demonstrated that spatial patterns of fMRI BOLD activity distribution over the brain may be used to classify different groups or mental states. These studies are based on the application of advanced pattern recognition approaches and multivariate statistical classifiers. Most published articles in this field are focused on improving the accuracy rates and many approaches have been proposed to accomplish this task. Nevertheless, a point inherent to most machine learning methods (and still relatively unexplored in neuroimaging) is how the discriminative information can be used to characterize groups and their differences. In this work, we introduce the Maximum Uncertainty Linear Discrimination Analysis (MLDA) and show how it can be applied to infer groups` patterns by discriminant hyperplane navigation. In addition, we show that it naturally defines a behavioral score, i.e., an index quantifying the distance between the states of a subject from predefined groups. We validate and illustrate this approach using a motor block design fMRI experiment data with 35 subjects. (C) 2008 Elsevier Inc. All rights reserved.

Auditory results from cochlear implants in elderly people

According to data from the Brazilian Institute of Geography and Statistics, the elderly population grew 47.8% in the last decade in Brazil. A portion of this population has severe and/or profound hearing loss and do not benefit from conventional hearing aids. Thus, the use of cochlear implant is required. Aim: To analyze the benefits of cochlear implants in the elderly based on the comparison of primary auditory thresholds before and after the operation, discrimination of sentences in speech and in talking on the telephone. Methodology: Retrospective cohort study, analyzing medical records from patients aged over 60 years, users of cochlear implant for at least 1 year. Results: Fourteen medical records were analyzed. Mean age of patients was 63.07 years. The mean pure tone thresholds between 500Hz, 1kHz, 2kHz and 4kHz before the implantation was 113dBHL. None of the patients, before operation, could discriminate sentences in open sets and only 3 scored 17% in closed sets sentence recognition. After one year of implantation, the mean sound field thresholds reached 34dBHL, and open set sentences recognition of 93.57%, while 71% of the patients had become able to have a conversation on the telephone. Conclusion: The elderly users of cochlear implant showed important outcomes, with significant improvement in understanding in the open set and in using the telephone.

Reliability of electromyographic amplitude values of the upper limb muscles during closed kinetic chain exercises with stable and unstable surfaces

The purpose of the present study was to evaluate the intra and interday reliability of surface electromyographic amplitude values of the scapular girdle muscles and upper limbs during 3 isometric closed kinetic chain exercises, involving upper limbs with the fixed distal segment extremity on stable base of support and on a Swiss ball (relatively unstable). Twenty healthy adults performed the exercises push-up, bench-press and wall-press with different effort levels (80% and 100% maximal load). Subjects performed three maximal voluntary contractions (MVC) in muscular testing position of each muscle to obtain a reference value for root mean square (RMS) normalization. Individuals were instructed to randomly perform three isometric contraction series, in which each exercise lasted 6 s with a 2-min resting-period between series and exercises. Intra and interday reliabilities were calculated through the intraclass correlation coefficient (ICC 2.1), standard error of the measurement (SEM). Results indicated an excellent intraday reliability of electromyographic amplitude values (ICC >= 0.75). The interday reliability of normalized RMS values ranged between good and excellent (ICC 0.52-0.98). Finally, it is suggested that the reliability of normalized electromyographic amplitude values of the analyzed muscles present better values during exercises on a stable surface. However, load levels used during the exercises do not seem to have any influence on variability levels, possibly because the loads were quite similar. (C) 2007 Elsevier Ltd. All rights reserved.