Medical device innovation in South Africa: Evolution of collaboration networks (2001-2013)

The evolution of medical device development in South Africa was investigated for the period 2001-2013. Collaboration networks for four sectors - academia, healthcare, industry, and science and support - were derived from a bibliometric study. Centrality measures identified dominant institutions. New actors entering the networks either exhibited preferential attachment to these institutions, or joined the network as part of an isolated cluster. Of the new institutions, foreign collaborators seldom stayed beyond five years, while local institutions seldom left after entering the field. Over the 13-year period, local collaboration activity persisted, while local-foreign collaborations were seen to decline. Over time, the network topology became more akin to that of a small-world network. The findings of the study may support innovation management by guiding institutional strategies for effective collaboration

Measurement of Skin Induration Size Using Smartphone Images and Photogrammetric Reconstruction: Pilot Study

Background: The tuberculin skin test (TST) is the most common method for detecting latent tuberculosis infection (LTBI). The test requires that a patient return to the health facility or be visited by a health care worker 48 to 72 hours after the intradermal placement of tuberculin so that the size of the resulting skin induration, if any, can be measured. Objective: This study aimed to propose and evaluate an image-based method for measuring induration size from images captured using a smartphone camera. Methods: We imaged simulated skin indurations, ranging from 4.0 to 19 mm, in 10 subjects using a handheld smartphone, and performed three-dimensional reconstruction of the induration sites using photogrammetry software. An experienced TST reader measured the size of each induration using the standard clinical method. The experienced reader and an inexperienced observer both measured the size of each induration using the software. The agreement between measurements generated by the standard clinical and image-based methods was assessed using the intraclass correlation coefficient (ICC). Inter- and intraobserver agreement for the image-based method was similarly evaluated. Results: Results showed excellent agreement between the standard and image-based measurements performed by the experienced reader with an ICC value of .965. Inter- and intraobserver agreements were also excellent, indicating that experience in reading TSTs is not required with our proposed method. Conclusions: We conclude that the proposed smartphone image-based method is a potential alternative to standard induration size measurement and would enable remote data collection for LTBI screening

Properties of the Chandra Sources in M81

The Chandra X-ray Observatory obtained a 50-ks observation of the central region of M81 using the ACIS-S in imaging mode. The global properties of the 97 x-ray sources detected in the inner 8.3x8.3 arcmin field of M81 are examined. Roughly half the sources are concentrated within the central bulge. The remainder are distributed throughout the disk with the brightest disk sources lying preferentially along spiral arms. The average hardness ratios of both bulge and disk sources are consistent with power law spectra of index Gamma~1.6 indicative of a population of x-ray binaries. A group of much softer sources are also present. The background source-subtracted logN-logS distribution of the disk follows a power law of index ~ -0.5 with no change in slope over three decades in flux. The logN-logS distribution of the bulge follows a similar shape but with a steeper slope above ~4.0e+37 ergs/s. There is unresolved x-ray flux from the bulge with a radial profile similar to that of the bulge sources. This unresolved flux is softer than the average of the bulge sources and extrapolating the bulge logN-logS distribution towards weaker sources can only account for 20% of the unresolved flux. No strong time variability was observed for any source with the exception of one bright, soft source.Comment: 5 pages, 3 color PS figures, to appear in ApJ

Analysis of plant LTR-retrotransposons at the fine-scale family level reveals individual molecular patterns

<p>Abstract</p> <p>Background</p> <p>Sugarcane is an important crop worldwide for sugar production and increasingly, as a renewable energy source. Modern cultivars have polyploid, large complex genomes, with highly unequal contributions from ancestral genomes. Long Terminal Repeat retrotransposons (LTR-RTs) are the single largest components of most plant genomes and can substantially impact the genome in many ways. It is therefore crucial to understand their contribution to the genome and transcriptome, however a detailed study of LTR-RTs in sugarcane has not been previously carried out.</p> <p>Results</p> <p>Sixty complete LTR-RT elements were classified into 35 families within four <it>Copia </it>and three <it>Gypsy </it>lineages. Structurally, within lineages elements were similar, between lineages there were large size differences. FISH analysis resulted in the expected pattern of <it>Gyps</it>y/heterochromatin, <it>Copia</it>/euchromatin, but in two lineages there was localized clustering on some chromosomes. Analysis of related ESTs and RT-PCR showed transcriptional variation between tissues and families. Four distinct patterns were observed in sRNA mapping, the most unusual of which was that of <it>Ale1</it>, with very large numbers of 24nt sRNAs in the coding region. The results presented support the conclusion that distinct small RNA-regulated pathways in sugarcane target the lineages of LTR-RT elements.</p> <p>Conclusions</p> <p>Individual LTR-RT sugarcane families have distinct structures, and transcriptional and regulatory signatures. Our results indicate that in sugarcane individual LTR-RT families have distinct behaviors and can potentially impact the genome in diverse ways. For instance, these transposable elements may affect nearby genes by generating a diverse set of small RNA's that trigger gene silencing mechanisms. There is also some evidence that ancestral genomes contribute significantly different element numbers from particular LTR-RT lineages to the modern sugarcane cultivar genome.</p

Split Supersymmetry from Anomalous U(1)

We present a scenario wherein the anomalous U(1) D-term of string origin triggers supersymmetry breaking and generates naturally a Split Supersymmetry spectrum. When the gaugino and the Higgsino masses (which are of the same order of magnitude) are set at the TeV scale, we find the scalar masses to be in the range (10^6 - 10^8) GeV. The U(1) D-term provides a small expansion parameter which we use to explain the mass and mixing hierarchies of quarks and leptons. Explicit models utilizing exact results of N = 1 suersymmetric gauge theories consistent with anomaly constraints, fermion mass hierarchy, and supersymmetry breaking are presented.Comment: 20 pages in LaTeX, version published in NPH

Comparison of breast and bowel cancer screening uptake patterns in a common cohort of South Asian women in England

Background: Inequalities in uptake of cancer screening by ethnic minority populations are well documented in a number of international studies. However, most studies to date have explored screening uptake for a single cancer only. This paper compares breast and bowel cancer screening uptake for a cohort of South Asian women invited to undertake both, and similarly investigates these women's breast cancer screening behaviour over a period of fifteen years. Methods: Screening data for rounds 1, 2 and 5 (1989-2004) of the NHS breast cancer screening programme and for round 1 of the NHS bowel screening pilot (2000-2002) were obtained for women aged 50-69 resident in the English bowel screening pilot site, Coventry and Warwickshire, who had been invited to undertake breast and bowel cancer screening in the period 2000-2002. Breast and bowel cancer screening uptake levels were calculated and compared using the chi-squared test. Results: 72,566 women were invited to breast and bowel cancer screening after exclusions. Of these, 3,539 were South Asian and 69,027 non-Asian; 18,730 had been invited to mammography over the previous fifteen years (rounds 1 to 5). South Asian women were significantly less likely to undertake both breast and bowel cancer screening; 29.9% (n = 1,057) compared to 59.4% (n = 40,969) for non-Asians (p < 0.001). Women in both groups who consistently chose to undertake breast cancer screening in rounds 1, 2 and 5 were more likely to complete round 1 bowel cancer screening. However, the likelihood of completion of bowel cancer screening was still significantly lower for South Asians; 49.5% vs. 82.3% for non-Asians, p < 0.001. South Asian women who undertook breast cancer screening in only one round were no more likely to complete bowel cancer screening than those who decided against breast cancer screening in all three rounds. In contrast, similar women in the non-Asian population had an increased likelihood of completing the new bowel cancer screening test. The likelihood of continued uptake of mammography after undertaking screening in round 1 differed between South Asian religio-linguistic groups. Noticeably, women in the Muslim population were less likely to continue to participate in mammography than those in other South Asian groups. Conclusions: Culturally appropriate targeted interventions are required to reduce observed disparities in cancer screening uptakes

Clinical and economic ramifications of switching antipsychotics in the treatment of schizophrenia

<p>Abstract</p> <p>Background</p> <p>Switching between antipsychotic medications is common in the treatment of schizophrenia. However, data on clinical and economic outcomes from antipsychotic switching, in particular acute care service use, is fairly limited. The goal of this research was to assess the clinical and economic ramifications of switching antipsychotics during outpatient management of schizophrenia.</p> <p>Methods</p> <p>Data from a 1-year randomized, open-label cost-effectiveness study involving typical and atypical antipsychotics were assessed. The study protocol permitted switching of antipsychotics when clinically warranted. The risk of crisis-related events, use of acute-care services, and the time to the initial use of such services were determined in outpatients who switched antipsychotics compared with those who continued with their initial medications. Health care resource utilization data were abstracted from medical records and other sources (e.g., patient self-report), and direct costs were estimated using previously published benchmarks.</p> <p>Results</p> <p>Almost one-third of patients (29.3%) underwent a switch from their initial antipsychotic agent, with an average duration of 100 days before such treatment alterations. Compared with their counterparts who remained on their initial therapies, individuals who switched antipsychotics experienced a significantly higher risk of acute-care services, including hospitalization (p = .013) and crisis services (p = .011). Patients undergoing medication switches also used acute-care services significantly sooner (p = .004) and accrued an additional $3,000 (a 25% increase) in annual total health care costs per patient, most of which was due to acute-care expenditures.</p> <p>Conclusion</p> <p>Switching antipsychotic medications was found to be associated with considerably poorer clinical and economic outcomes, as reflected by, more frequent and more rapid use of acute-care services compared with persons remaining on their initial treatments.</p> <p>Trial Registration</p> <p>Trial ID 2325 in LillyTrials.com (also accessible via ClinicalStudyResults.org).</p

Quivers, words and fundamentals

40 pages + Appendices, 9 figures40 pages + Appendices, 9 figure

The effect of Ku on telomere replication time is mediated by telomere length but is independent of histone tail acetylation

Peer reviewedPublisher PD

Sociological and Communication-Theoretical Perspectives on the Commercialization of the Sciences

Both self-organization and organization are important for the further development of the sciences: the two dynamics condition and enable each other. Commercial and public considerations can interact and "interpenetrate" in historical organization; different codes of communication are then "recombined." However, self-organization in the symbolically generalized codes of communication can be expected to operate at the global level. The Triple Helix model allows for both a neo-institutional appreciation in terms of historical networks of university-industry-government relations and a neo-evolutionary interpretation in terms of three functions: (i) novelty production, (i) wealth generation, and (iii) political control. Using this model, one can appreciate both subdynamics. The mutual information in three dimensions enables us to measure the trade-off between organization and self-organization as a possible synergy. The question of optimization between commercial and public interests in the different sciences can thus be made empirical.Comment: Science & Education (forthcoming