77,596 research outputs found
Transthoracic three-dimensional echocardiography for the assessment of straddling tricuspid or mitral valves
Background The advent of 3D echocardiography has provided a technique which, potentially, could afford significant additional information over conventional cross-sectional echocardiography in the assessment of patients with straddling atrioventricular valves prior to surgical correction. Methods Eight patients, aged from 1 month to 9Ë2 years, were examined with 3D echocardiography. All but three had discordant ventriculoarterial connections or double outlet right ventricle. Data suitable for reconstruction was acquired with transthoracic scanning. Right and left ventricular volumes were calculated in the 3D dataset. Results 3D echocardiography proved capable of defining the exact degree of straddling by imaging theproportion of tension apparatus attached to either side of the ventricular septum. It was able also to display the atrioventricular junction âen faceâ, thus permitting identification of the precise site of insertion of the muscular ventricular septum relative to the atrioventricular junction. This made it possiblefirst, to calculate the degree of valvar override, and second, to predict the location of the penetrating atrioventricular bundle. End-diastolic volume of the right ventricle in those with straddling tricuspid valves was 73 (61â83)% of normal, and, of the left ventricle in those with mitral valvar straddling 71 (40â97)% of normal. Conclusions 3D echocardiography can aid in planning the optimal surgical procedure in patients with straddling or overrriding atrioventricular valves, as it provides diagnostic information superiorto standard crosssectional techniques. It also allows for exact measurement of the volumes of the respective ventricles
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The Dialectics of Parenting: Changes in the Interplay of Maternal Behaviors during Early and Middle Childhood
Parent and child relationships continuously evolve, part of an ongoing dialectic that derives from developmental changes in both parent and child. The focus of this study is on changes in the strength of association among four types of parenting behaviors considered important for childrenâs development: supportive presence, respect for autonomy, stimulation, and hostility. Motherâchild interaction was observed for 1229 parentâchild dyads at 36 months, 54 months, 1st grade, 3rd grade, and 5th grade using similar observational paradigms. The association between respect for autonomy and supportive presence was strong at age three and continued to be strong over time. The association between respect for autonomy and stimulation was modest but also showed little change from age three to 5th grade. Respect for autonomy was negatively associated with maternal hostility, but the relation was complex. It was stronger at 54 months than 36 months but then became weaker through time. Supportive presence showed a moderate relation with stimulation at age 3 but the association became weaker over time. Supportive presence showed an expected negative association with hostility, a relation that changed little over time. The relation between hostility and stimulation also became weaker over time. In effect, there appears to be a shifting pattern of relations between maternal behaviors during early and middle childhood, one that reflects an evolving dialectic in the motherâchild relationship
Enhanced Bragg reflections from size-matched heterostructure photonic crystal thin films prepared by the Langmuir-Blodgett method
The Langmuir-Blodgett method was used to engineer photonic crystal thin films of an AB architecture. Structures were studied by transmittance and reflectance spectroscopies. For an AB structure in which the silica particle diameter B is twice that of A, reflectance features associated with the first order Bragg peak for the ``A'' domain are only observed when the structure is probed from the A side of the structure. Furthermore, this feature is enhanced in intensity compared to that for a structure consisting solely of A particles. These findings are attributed to a matching of first and second order Bragg processes
The game transfer phenomena scale: an instrument for investigating the nonvolitional effects of video game playing
A variety of instruments have been developed to assess different dimensions of playing videogames and its effects on cognitions, affect, and behaviors. The present study examined the psychometric properties of the Game Transfer Phenomena Scale (GTPS) that assesses non-volitional phenomena experienced after playing videogames (i.e., altered perceptions, automatic mental processes, and involuntary behaviors). A total of 1,736 gamers participated in an online survey used as the basis for the analysis. Confirmatory factor analysis (CFA) was performed to confirm the factorial structure of the GTPS. The five-factor structure using the 20 indicators based on the analysis of gamersâ self-reports fitted the data well. Population cross-validity was also achieved and the positive associations between the session length and overall scores indicate the GTPS warranted criterion-related validity. Although the understanding of GTP is still in its infancy, the GTPS appears to be a valid and reliable instrument for assessing non-volitional gaming-related phenomena. The GTPS can be used for understanding the phenomenology of post-effects of playing videogames
The relative fitness of drug-resistant Mycobacterium tuberculosis: a modelling study of household transmission in Peru.
The relative fitness of drug-resistant versus susceptible bacteria in an environment dictates resistance prevalence. Estimates for the relative fitness of resistant Mycobacterium tuberculosis (Mtb) strains are highly heterogeneous and mostly derived from in vitro experiments. Measuring fitness in the field allows us to determine how the environment influences the spread of resistance. We designed a household structured, stochastic mathematical model to estimate the fitness costs associated with multidrug resistance (MDR) carriage in Mtb in Lima, Peru during 2010-2013. By fitting the model to data from a large prospective cohort study of TB disease in household contacts, we estimated the fitness, relative to susceptible strains with a fitness of 1, of MDR-Mtb to be 0.32 (95% credible interval: 0.15-0.62) or 0.38 (0.24-0.61), if only transmission or progression to disease, respectively, was affected. The relative fitness of MDR-Mtb increased to 0.56 (0.42-0.72) when the fitness cost influenced both transmission and progression to disease equally. We found the average relative fitness of MDR-Mtb circulating within households in Lima, Peru during 2010-2013 to be significantly lower than concurrent susceptible Mtb If these fitness levels do not change, then existing TB control programmes are likely to keep MDR-TB prevalence at current levels in Lima, Peru
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The introduction of an holistic design approach through a teaching company scheme
Traditional design approaches separate the various functions of design such as material selection, performance modelling and tolerance specification into discrete entities. Whilst this allows more focused methods to be used at each stage, areas of conflict or benefit may be overlooked, and the designer is left to bring the loose ends together. This paper looks at a synthesis approach that draws upon a number of current design themes. The design process is considered along with various aspects such as product development, design-for-`X' methodologies and material selection. The need for the preservation of design knowledge and reasoning, the so called wh-? questions, within the process are considered along with various models of the design process. The paper draws these various aspects together to form a more holistic approach to design. The application of this technique within the Teaching Company Scheme is briefly discussed
Use of novel serum markers in clinical follow-up of Sertoli-Leydig cell turnours
Background: Sertoli-Leyclig cell tumours of the ovary account for only 0.2% of malignant ovarian tumours. Two-thirds of all patients become apparent due to the tumour's hormone production. Methods: A 41-year-old patient (gravida 4, para 4) presented with dyspnoea, enlarged abdominal girth and melaena. Diagnostic imaging was suspicious for an ovarian cancer. The standard tumour marker for ovarian cancer (CA 125) was elevated to 984 U/mL. Results: Surgical exploration of the abdomen revealed a mouldering tumour of both adnexes extending to the level of the navel. Frozen sections showed an undifferentiated carcinoma of unknown origin. Radical surgery was performed. The final histological report described a malignant sex-cord stroma tumour, a Sertoli-Leydig cell tumour, emanating from both ovaries. Analysis of preoperative blood serum showed elevated levels of CYFRA 21-1 (10.4 ng/mL), neuron-specific enolase (36.2 ng/mL), oestradiol (485 pg/mL) and CA-125 (984 U/mL). Adjuvant chemotherapy and regional hyperthermia were performed due to the malignant potential and incomplete resection of the tumour. Conclusions: Undifferentiated Sertoli-Leyclig cell tumours show a poor clinical course. As only two-thirds of patients with this rare disease present with elevated hormone levels, new markers deserve further investigation to offer more specific, individualised tumour monitoring
Detection of the glucocorticoid receptors in brain protein extracts by SDS-PAGE
Uncorrected proofGlucocorticoids are steroid hormones vital for organ system homeostasis and for the maintenance of essential biological processes. A significant part of these actions are mediated through glucocorticoid receptor (GR) that belongs to the nuclear receptor superfamily. To cover such variety of processes the different glucocorticoids act through different GR isoforms that are originated due to posttranscriptional and posttranslational mechanisms. For this reason when evaluating the levels of GRs we should preferentially determine protein levels instead of gene expression. Here, we describe the detection by Western blotting of the GR (a and Ă isoforms) protein, using macrodissected brain tissue
In-orbit Vignetting Calibrations of XMM-Newton Telescopes
We describe measurements of the mirror vignetting in the XMM-Newton
Observatory made in-orbit, using observations of SNR G21.5-09 and SNR
3C58 with the EPIC imaging cameras. The instrument features that complicate
these measurements are briefly described. We show the spatial and energy
dependences of measured vignetting, outlining assumptions made in deriving the
eventual agreement between simulation and measurement. Alternate methods to
confirm these are described, including an assessment of source elongation with
off-axis angle, the surface brightness distribution of the diffuse X-ray
background, and the consistency of Coma cluster emission at different position
angles. A synthesis of these measurements leads to a change in the XMM
calibration data base, for the optical axis of two of the three telescopes, by
in excess of 1 arcminute. This has a small but measureable effect on the
assumed spectral responses of the cameras for on-axis targets.Comment: Accepted by Experimental Astronomy. 26 pages, 18 figure
Competence and Performance of the Skilled Birth Attendants to undertake Normal Delivery and Emergency Obstetric Care in Eritrea.
Objective: to determine the competence and performance of the skilled birth attendants and the quality of normal delivery and emergency obstetric services in Eritrea.
Methods: All of the 17 hospitals that provide maternity services and all of the 46 health centers in the country
were included in this study. Quality or Quality gap was assessed through measuring the percentage of clients
who got a service in compliance with the standards described in the national safe motherhood protocol.
Findings: The study revealed gaps in the competence and performance of the skilled health workers as well
as in the quality of normal delivery and emergency obstetric services in the country. Among the quality gaps
identified were poor monitoring of normal and complicated labor and lack of use of partographs.
Conclusion: The study concluded that in order to reduce maternal morality in developing countries like Eritrea;
it is not adequate to just increase the percentage of women who are attended by health professionals, it is also at least equally important to improve the skills and performance of the available birth attendants
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