In two experiments, we examined the attentional mechanisms governing sensorimotor skill execution across levels of expertise. In Experiment 1, novice and expert golfers took a series of putts under dual-task conditions designed to distract attention from putting and under skill-focused conditions that prompted attention to step-by-step performance. Novices performed better under skill-focused than under dual-task conditions.
View Article and Find Full Text PDFActa Crystallogr D Biol Crystallogr
July 2004
Recently, the multivariate complex normal distribution has been used to develop a maximum-likelihood probability function for single-wavelength anomalous diffraction phasing and refinement of heavy-atom parameters [Pannu & Read (2004), Acta Cryst. D60, 22-27]. The function accounts explicitly for the correlations between the observed and calculated Friedel mates and their errors.
View Article and Find Full Text PDFExperiences with the molecular-replacement program Beast have shown that maximum-likelihood rotation targets are more sensitive to the correct orientation than traditional targets. However, this comes at a high computational cost: brute-force rotation searches can take hours or even days of computation time on current desktop computers. Series approximations to the full likelihood target have been developed that can be computed by fast Fourier transforms in minutes.
View Article and Find Full Text PDFThe purpose of this study was to evaluate the efficacy and toxicity of the preparative regimen of thiotepa and etoposide in patients undergoing autologous transplantation for relapsed non-Hodgkin's lymphoma. The study involved 65 consecutive patients who underwent autologous transplantation using the thiotepa/etoposide regimen for relapsed intermediate-grade NHL at the University of Wisconsin Hospital and Clinics (UWHC) between 1987 and 2001. The regimen consisted of thiotepa 300 mg/m(2)/day and etoposide 700 mg/m(2)/day on days -6, -5, and -4.
View Article and Find Full Text PDFMovement selection depends on the outcome of prior behavior. Posterior cingulate cortex (CGp) is strongly connected with both limbic and oculomotor circuitry, and CGp neurons respond following saccades, suggesting a role in signaling the motivational outcome of gaze shifts. To test this hypothesis, single CGp neurons were studied in monkeys while they shifted gaze to visual targets for liquid rewards that varied in size or were delivered probabilistically.
View Article and Find Full Text PDFA new software system called PHENIX (Python-based Hierarchical ENvironment for Integrated Xtallography) is being developed for the automation of crystallographic structure solution. This will provide the necessary algorithms to proceed from reduced intensity data to a refined molecular model, and facilitate structure solution for both the novice and expert crystallographer. Here, the features of PHENIXare reviewed and the recent advances in infrastructure and algorithms are briefly described.
View Article and Find Full Text PDFThe aim of this study was to determine the reliability and magnitude of error of three lower-limb clinical measures for children with cerebral palsy (CP): the Modified Ashworth Scale of Spasticity (MAS), passive range of movement (PROM) and the modified Tardieu scale (MTS). Six physiotherapists measured 11 females and seven males (mean age 6 years 4 months, SD 2 years 4 months; age range 2 years 4 months to 10 years) on two occasions using a repeated measures design, collecting all data over 6 days. The severity of CP spanned all five levels of the Gross Motor Function Classification System and all children demonstrated varying degrees of spasticity.
View Article and Find Full Text PDFActa Crystallogr D Biol Crystallogr
October 2003
Probabilistic methods involving maximum-likelihood parameter estimation have become a powerful tool in computational crystallography. At the centre of these methods are the relevant probability distributions. Here, equations are developed based on the complex multivariate normal distribution that generalize the distributions currently used in maximum-likelihood model and heavy-atom refinement.
View Article and Find Full Text PDFObjective: To examine variability in 'uptime' (the amount of time spent in the upright position).
Design: An observational study.
Setting: The community (i.
The 22 nucleotide let-7 small temporal RNA has been found consistently in samples from diverse bilateria but not from sponge or cnidarians. Here we further examine the phylogenetic distribution of this regulatory RNA by sampling representatives of diverse metazoan lineages. The 22 nucleotide let-7 RNA is detectable in triclad and polyclad platyhelminths, nemertean, and chaetognath but not ctenophore or acoel metazoans.
View Article and Find Full Text PDFAdvanced glycation end-product (AGE)-damaged IgG occurs as a result of hyperglycemia and/or oxidative stress. Autoantibodies to IgG-AGE were previously demonstrated in patients with severe, longstanding rheumatoid arthritis (RA). We investigated whether IgG-AGE and anti-IgG-AGE antibodies were present early in the course of RA and other inflammatory arthropathies.
View Article and Find Full Text PDFThe 'Uptimer' is a custom-made lightweight battery-operated remote activity monitor that records the amount of time an individual spends in the upright position, which is also known as 'uptime'. The aims of this study were to determine levels of uptime over 24 hours and the relation between uptime and a child's age, sex, height, weight, and body mass index (BMI). Uptime was recorded in 529 normally developing children (318 females, 211 males), aged between 8 and 15 years.
View Article and Find Full Text PDFAntithrombin is a member of the serpin family of protease inhibitors and the major inhibitor of the blood coagulation cascade. It is unique amongst the serpins in that it circulates in a conformation that is inactive against its target proteases. Activation of antithrombin is brought about by a conformational change initiated upon binding heparin or heparan sulphate.
View Article and Find Full Text PDFOrganisms of Chlamydia spp. are obligate intracellular, gram-negative bacteria with a dimorphic developmental cycle that takes place entirely within a membrane-bound vacuole termed an inclusion. The chlamydial anomaly refers to the fact that cell wall-active antibiotics inhibit Chlamydia growth and peptidoglycan (PG) synthesis genes are present in the genome, yet there is no biochemical evidence for synthesis of PG.
View Article and Find Full Text PDFCurr Opin Struct Biol
October 2002
Maximum likelihood methods are well known to macromolecular crystallographers as the methods of choice for isomorphous phasing and structure refinement. Recently, the use of maximum likelihood and Bayesian statistics has extended to the areas of molecular replacement and density modification, placing these methods on a stronger statistical foundation and making them more accurate and effective.
View Article and Find Full Text PDFWe evaluated gross motor function following botulinum toxin A (BTX-A) injections in the lower limbs of children with spastic cerebral palsy in a randomized clinical trial, using a cross-over design. Forty-nine children (24 males, 25 females, age range 22 to 80 months) were randomly allocated to two groups: group 1 received BTX-A and physiotherapy, and group 2 received physiotherapy alone for 6 months. At the end of this period, group 2 received BTX-A and physiotherapy and group 1 continued with physiotherapy alone.
View Article and Find Full Text PDFSalmonella enterica serovar Typhimurium encounters antimicrobial peptides (AP) within the phagosomes of professional phagocytes and at intestinal mucosal surfaces. Salmonella serovar Typhimurium utilizes the two-component regulatory system PmrA-PmrB, which is activated in response to the environmental conditions encountered in vivo, to regulate resistance to several AP, including polymyxin B (PM). Random MudJ transposon mutagenesis was used to identify PmrA-PmrB-regulated genes, as well as genetic loci necessary for PM resistance.
View Article and Find Full Text PDFActa Crystallogr D Biol Crystallogr
November 2002
Structural genomics seeks to expand rapidly the number of protein structures in order to extract the maximum amount of information from genomic sequence databases. The advent of several large-scale projects worldwide leads to many new challenges in the field of crystallographic macromolecular structure determination. A novel software package called PHENIX (Python-based Hierarchical ENvironment for Integrated Xtallography) is therefore being developed.
View Article and Find Full Text PDFResearchers set out to determine which of two methods for preventing heel pressure ulcers yields more effective results.
View Article and Find Full Text PDFAP2 is the best-characterized member of the family of heterotetrameric clathrin adaptor complexes that play pivotal roles in many vesicle trafficking pathways within the cell. AP2 functions in clathrin-mediated endocytosis, the process whereby cargo enters the endosomal system from the plasma membrane. We describe the structure of the 200 kDa AP2 "core" (alpha trunk, beta2 trunk, mu2, and sigma2) complexed with the polyphosphatidylinositol headgroup mimic inositolhexakisphosphate at 2.
View Article and Find Full Text PDFObjectives: To explore patients' understanding of their symptoms and the treatment of their heart failure.
Design: Qualitative analysis of in-depth interviews, using a constant comparative approach.
Subjects: 27 patients identified by Cardiology and Care of the Elderly physicians as having (a) symptomatic heart failure (New York Heart Association functional classes II, III and IV) and (b) a hospital admission for heart failure in the previous 20 months.
The effects of hemagglutinin (HA) fusion peptide (X-31) on poly(ethylene glycol)- (PEG-) mediated vesicle fusion in three different vesicle systems have been compared: dioleoylphosphatidylcholine (DOPC) small unilamellar vesicles (SUV) and large unilamellar vesicles (LUV) and palmitoyloleoylphosphatidylcholine (POPC) large unilamellar perturbed vesicles (pert. LUV). POPC LUVs were asymmetrically perturbed by hydrolyzing 2.
View Article and Find Full Text PDFFaraday Discuss
December 2001
In this paper, a multiple configurational time-dependent self-consistent field (TDSCF) approach for studying photodissociation and reaction dynamics is described. This approach has been applied to studies of several benchmark systems and is found to provide an accurate description of the reactions. The focus of the present work is on investigations of processes in cluster environments.
View Article and Find Full Text PDFAntimicrob Agents Chemother
July 2001
Antimicrobial peptides (APs) are important components of the innate defenses of animals, plants, and microorganisms. However, some bacterial pathogens are resistant to the action of APs. For example, Proteus mirabilis is highly resistant to the action of APs, such as polymyxin B (PM), protegrin, and the synthetic protegrin analog IB-367.
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