Exploring the origin of Turbulent Taylor rolls

Since Taylor's seminal paper, the existence of large-scale quasi-axisymmetric structures has been a matter of interest when studying Taylor-Couette flow. In this manuscript, we probe their formation in the highly turbulent regime by conducting a series of numerical simulations at a fixed Reynolds number $Re_s=3.6\times 10^4$ while varying the Coriolis parameter to analyze the flow characteristics as the structures arise and dissipate. We show how the Coriolis force induces a one-way coupling between the radial and azimuthal velocity fields inside the boundary layer, but in the bulk there is a two-way coupling that causes competing effects. We discuss how this complicates the analogy of narrow-gap Taylor-Couette to other convective flows. We then compare these statistics to a similar shear flow without no-slip boundary layers, showing how this double coupling causes very different effects. We finish by reflecting on the possible origins of turbulent Taylor rolls

Longevity of immediate rehabilitation with direct metal-wire reinforced composite fixed partial dentures.

OBJECTIVES This study aimed to analyze the longevity of direct metal-wire reinforced composite fixed partial dentures (MRC-FPD) and factors influencing their survival and success. METHODS Within one private practice 513 MRC-FPD were directly applied. The preparation of a proximal cavity in abutment teeth was not limited. MRC-FPD were reinforced by one to three metal-wires. At the last follow-up MRC-FPD were considered successful, if they were still in function without any need of therapy. MRC-FPD were considered as survived, if they were repaired or replaced. Multi-level Cox proportional hazard models were used to evaluate the association between clinical factors and time. RESULTS Mean follow-up period (range) was 59(2-249) months. Seventy-three bridges did not survive (cumulative survival rate(CSR):86%) and further 129 bridges had received a restorative follow-up treatment (CSR:61%). AFR was 2.2% for survival and 8.6% for success. In multivariate analysis MRC-FPD with> 1 wire showed a up to 2.3x higher failure rate than MRC-FPD with one wire(p ≤ 0.023). Dentist's experience in designing MRC-FDP (p ≤ 0.017), patient's caries risk (p ≤ 0.040) and bruxism (p = 0.033) significantly influenced the failure rate: the more experience, the lower caries risk and bruxism, the lower the failure rate. SIGNIFICANCE For directly prepared metal-wire reinforced composite bridges high survival and moderate success rates were observed. MRC-FPD might, thus, be an immediate, short- and medium-term solution for replacing missing teeth. However, several factors on the levels of practice (dentist's experience in designing MRC-FDP), patient (bruxism, caries risk) and restoration (number of wires) were identified as significant predictors for the failure rate. The study was registered in the German Clinical Trials Register (DRKS-ID: DRKS00021576)

Preliminary analysis of fluctuations in the received uplink-beacon-power data obtained from the GOLD experiments

Uplink data from recent free-space optical communication experiments carried out between the Table Mountain Facility and the Japanese Engineering Test Satellite are used to study fluctuations caused by beam propagation through the atmosphere. The influence of atmospheric scintillation, beam wander and jitter, and multiple uplink beams on the statistics of power received by the satellite is analyzed and compared to experimental data. Preliminary analysis indicates the received signal obeys an approximate lognormal distribution, as predicted by the weak-turbulence model, but further characterization of other sources of fluctuations is necessary for accurate link predictions

Plasma Fibrinogen and Platelet Mass as Indicators of the Prothrombotic and Systemic Inflammatory State in COPD

INTRODUCTION : COPD is a disease of increasing public health importance around the world. GOLD estimates suggest that COPD will rise from the sixth to the third most common cause of death worldwide by 2020. Worldwide, COPD is the only leading cause of death that still has a rising mortality. Even though there have been significant advances in the understanding and management of COPD, the disease may be largely preventable, but it remains marginally treatable. It is well known that COPD is a syndrome of progressive airflow limitation caused chronic inflammation of the airways and lung parenchyma. But it also produces significant systemic consequences. The role of systemic inflammation as evidenced by the rise in inflammatory markers is now being increasingly recognised to play an important role in the systemic effects. The systemic effects include cachexia, skeletal muscle dysfunction, cardiovascular disease, osteoporosis, depression, fatigue among many others. It is also found that there is an ongoing hypercoagulable state in COPD. It is evidenced by the increased incidence of pulmonary thrombosis and coronary artery disease in these patients. The hypercoagulable state is being attributed to altered platelet functions and clotting system activation as has been shown by increased platelet size, high blood fibrinogen levels in patients with COPD. AIMS AND OBJECTIVES: The aims of the study were as follows; 1. To study the plasma fibrinogen level in patients with COPD. 2. To study the mean platelet volume in patients with COPD. 3. To study the correlation between plasma fibrinogen level and mean platelet volume and severity of COPD. MATERIALS AND METHODS: Study Design: Case Control Study . Period of Study: June 2008 To June 2009. Materials/Selection Of Study Subjects: Outpatients and Inpatients Visiting the Medical and Thoracic Medicine Department and On Healthy Volunteering Controls. Consent : Informed Consent Obtained from Cases and Controls. Conflict Of Interest : Nil. Financial Support: Nil. For Cases: Inclusion Criteria: 1. Male patients with Chronic obstructive pulmonary disease (FEV1/FVC <70%). 2. Ex- smokers (who has quit smoking for > 15 years). Exclusion Criteria: 1. Patients in Acute exacerbation, 2. Bronchial asthma (improvement of FEV1 by >15%after bronchodilator suggesting reversibility of airflow obstruction), 3. Restrictive lung diseases (FVC/FEV1 ≥ 70%; Predicted FEV1% < 80%), 4. Pulmonary tuberculosis, 5. Bronchiectasis, 6. Malignancies, 7. Acute infections, 8. Inflammatory disorders (eg.,Rheumatoid arthritis, glomerulonephritis), 9. Cardiac failure, 10. Acute Myocardial infarction , Acute stroke, 11. Significant trauma, 12. Patients refusing consent. SUMMARY: The study “Plasma Fibrinogen and Platelet Mass as Indicators of the Systemic Inflammatory and Prothrombotic state in COPD” was a case control study conducted on 75 COPD patients and 75 healthy controls in Govt. Rajaji Hospital, Madurai. Patients and controls who satisfied the inclusion criteria were included in the study and detailed history was elicited from them. They underwent investigations like, lung function tests, plasma fibrinogen, mean platelet volume, PaO2 measurements. COPD patients were found to have significantly elevated plasma fibrinogen and mean platelet volume. Plasma fibrinogen and mean platelet volume significantly correlated with severity of COPD. Also, they had significantly elevated ESR, leucocyte count and platelet count. Platelet count significantly correlated with the severity of COPD. Hence, it can be concluded that there is systemic inflammatory prothrombotic state in COPD. Also, the systemic inflammation increases with the severity of COPD. CONCLUSION: 1. There is an increased Fibrinogen level in patients with COPD. 2. There is an increased Mean Platelet Volume in patients with COPD. 3. Fibrinogen and Mean Platelet Volume increases as the severity of COPD increases. 4. There is also an increased leucocyte count, platelet count, ESR in patients with COPD. 5. This indicates that there is Systemic Inflammatory and Prothrombotic state in COPD. 6. Systemic Inflammation increases as the severity of COPD increases