Co-occurrence of outlet impingement syndrome of the shoulder and restricted range of motion in the thoracic spine - a prospective study with ultrasound-based motion analysis

<p>Abstract</p> <p>Background</p> <p>Shoulder complaints, and especially the outlet-impingement syndrome, are a common condition. Among other things, poor posture has been discussed as a cause. A correlation between impingement syndrome and restricted mobility of the thoracic spine (T) has been described earlier, but there has been no motion analysis of the thoracic spine to show these correlations. In the present prospective study, we intended to find out whether there is a significant difference in the thoracic sagittal range of motion (ROM) between patients with a shoulder outlet impingement syndrome and a group of patients who had no shoulder pathology. Secondly, we wanted to clarify whether Ott's sign correlates with ultrasound topometric measurements.</p> <p>Methods</p> <p>Two sex- and age-matched groups (2 × n = 39) underwent a clinical and an ultrasound topometric examination. The postures examined were sitting up straight, sitting in maximal flexion and sitting in maximal extension. The disabilities of the arm, shoulder and hand (DASH) score (obtained by means of a self-assessment questionnaire) and the Constant score were calculated. Lengthening and shortening of the dorsal projections of the spine in functional positions was measured by tape with Ott's sign.</p> <p>Results</p> <p>On examination of the thoracic kyphosis in the erect seated posture there were no significant differences between the two groups (p = 0.66). With ultrasound topometric measurement it was possible to show a significantly restricted segmental mobility of the thoracic spine in the study group compared with the control group (p = 0.01). An in-depth look at the mobility of the subsegments T1-4, T5-8 and T9-12 revealed that differences between the groups in the mobility in the lower two sections of the thoracic spine were significant (T5-8: p = 0.03; T9-12: p = 0.02). The study group had an average Constant score of 35.1 points and the control group, 85.5 (p < 0.001). On the DASH score the patient group reached 34.2 points and the control group, 1.4 (p < 0.001). The results of Ott's sign differed significantly between the two collectives (p = 0.0018), but showed a weak correlation with the ultrasound topometric measurements (study group flexion/extension: r = 0.36/0.43, control group flexion/extension: r = 0.29/0.26).</p> <p>Conclusion</p> <p>The mobility of the thoracic spine should receive more attention in the diagnosis and therapy of patients with shoulder outlet impingement syndrome.</p

The effect of prehydration on the engineering properties of CEM I Portland cement

Prehydration; the reaction between anhydrous cement and water vapour, has deleterious effects on engineering properties including compressive strength, workability and setting time. This study has assessed changes in engineering properties of CEM I Portland cement exposed to relative humidities of 60% or 85% for 7 and 28 days. Thin layers of CEM I 42.5R cement, no more than 2 mm thick, were exposed to controlled relative humidities of 60 and 85%., followed by assessment of compressive strength, setting time and workability. These measurements were complemented by characterising the prehydrated anhydrous cement using isothermal calorimetry, scanning electron microscopy, x-ray diffraction and thermal gravimetric analysis. Following prehydration at 60% relative humidity, conventional hydration resulted in a negligible reduction in strength development plus a decrease in workability and increase in setting time. At 85% relative humidity, compressive strength was greatly reduced, particularly at early ages. There was also a greater loss of workability and increase in setting time

Population structure of mixed Mycobacterium tuberculosis infection is strain genotype and culture medium dependent

Contains fulltext : 125779.pdf (publisher's version ) (Open Access)BACKGROUND: Molecular genotyping methods have shown infection with more than one Mycobacterium tuberculosis strain genotype in a single sputum culture, indicating mixed infection. AIM: This study aimed to develop a PCR-based genotyping tool to determine the population structure of M. tuberculosis strain genotypes in primary Mycobacterial Growth Indicator Tubes (MGIT) and Lowenstein-Jensen (LJ) cultures to identify mixed infections and to establish whether the growth media influenced the recovery of certain strain genotypes. METHOD: A convenience sample of 206 paired MGIT and LJ M. tuberculosis cultures from pulmonary tuberculosis patients resident in Khayelitsha, South Africa were genotyped using an in-house PCR-based method to detect defined M. tuberculosis strain genotypes. RESULTS: The sensitivity and specificity of the PCR-based method for detecting Beijing, Haarlem, S-family, and LAM genotypes was 100%, and 75% and 50% for detecting the Low Copy Clade, respectively. Thirty-one (15%) of the 206 cases showed the presence of more than one M. tuberculosis strain genotype. Strains of the Beijing and Haarlem genotypes were significantly more associated with a mixed infection (on both media) when compared to infections with a single strain (Beijing MGIT p = 0.02; LJ, p<0.01) and (Haarlem: MGIT p<0.01; LJ, p = 0.01). Strains with the Beijing genotype were less likely to be with "other genotype" strains (p<0.01) while LAM, Haarlem, S-family and LCC occurred independently with the Beijing genotype. CONCLUSION: The PCR-based method was able to identify mixed infection in at least 15% of the cases. LJ media was more sensitive in detecting mixed infections than MGIT media, implying that the growth characteristics of M. tuberculosis on different media may influence our ability to detect mixed infections. The Beijing and Haarlem genotypes were more likely to occur in a mixed infection than any of the other genotypes tested suggesting pathogen-pathogen compatibility

Innovation and ownership variety

The role of ownership heterogeneity in influencing the extent and nature of innovation has been neglected but is an important omission as ownership differences can influence the goals, time horizons, and governance mechanisms relating to innovation. In this article I develop a novel framework that explores the potential impact and future research avenues in firms with a variety of ownership forms based on whether the organizational form in which innovation takes place is either a new venture or an existing business, and whether ownership involves new independent owners or existing independent owners of the organization. With respect to organizational form, new ventures are effectively locked into innovation by definition, while existing businesses may find a balance between investing in innovation and exploiting previous innovations, and engaging in more incremental innovation. Existing independent owners may be expected to take a more sustained view of innovation over time while new owners may be time delimited in their innovation. On the basis of this framework I analyze the following ownership types: academic spin-offs, private equity backed management buyouts, family firms and firms owned by habitual entrepreneurs. I identify the need for research to explore other ownership forms and the interaction between ownership types and different contexts