Correlation of transonic-cone preston-tube data and skin friction

Preston-tube measurements obtained on the Arnold Engineering Development Center (AEDC) Transition Cone have been correlated with theoretical skin friction coefficients in transitional and turbulent flow. This has been done for the NASA Ames 11-Ft Transonic Wind Tunnel (11 TWT) and flight tests. The developed semi-empirical correlations of Preston-tube data have been used to derive a calibration procedure for the 11 TWT flow quality. This procedure has been applied to the corrected laminar data, and an effective freestream unit Reynolds number is defined by requiring a matching of the average Preston-tube pressure in flight and in the tunnel. This study finds that the operating Reynolds number is below the effective value required for a match in laminar Preston-tube data. The distribution of this effective Reynolds number with Mach number correlates well with the freestream noise level in this tunnel. Analyses of transitional and turbulent data, however, did not result in effective Reynolds numbers that can be correlated with background noise. This is a result of the fact that vorticity fluctuations present in transitional and turbulent boundary layers dominate Preston-tube pressure fluctuations and, therefore, mask the tunnel noise eff ects. So, in order to calibrate the effects of noise on transonic wind tunnel tests only laminar data should be used, preferably at flow conditions similar to those in flight tests. To calibrate the effects of transonic wind-tunnel noise on drag measurements, however, the Preston-tube data must be supplemented with direct measurements of skin friction

Risk Quotient of Airborne Paraquat Exposure Among Workers in Palm Oil Plantation

Paraquat is the herbicide widely used at palm oil plantations, although usage it in some countries has been banned and restricted. Paraquat spraying was not appropriate procedure could be polluted the environment and lead to health disorders workers. Paraquat could enter the body through inhalation, dermal and ingestion, one of frequent routes through inhalation during spraying weeds in plantation areas. This study aimed was to analyze potential inhalation dose and Risk Quotient to workers at palm oil plantation. This research was a descriptive study with cross sectional design and analysis of environmental health risk methods. Airborne Paraquat residue was collected from 8 workers with occupational activity as a supervisor and sprayer. Airborne Paraquat residue was measured for 25 minutes during spraying by using personal air sampler at worker's breathing zone. Airborne Paraquat residue was detected by High Performance Liquid Chromatography (HPLC) with NIOSH 5003 methods. The average of airborne Paraquat residue was 0.0125 mg/m3, it values was less than the Threshold Limit Value (0.05 mg/m3) of American Conference of Government Industrial Hygienists, but the average of potential inhalation dose was 0.001 mg/kg/day for worker's weight 55 kg, it was value higher than Acceptable Operator Exposure Limit (0.0005 mg/kg/day) and the calculation of Risk Quotient (RQ) was more than 1, it conditions was unacceptable for workers. Although, airborne Paraquat residue were safe, but potential inhalation dose and Risk Quotient (RQ) were unsafe for workers, cause it can be lead to lung function disorders. Therefore, for further studies it was necessary to assess the lung function of workers and the use of personal protective equipment must be completely and standard

Lessons from Stuxnet

Malware such as Stuxnet can affect critical physical infra-structures that are controlled by software, which implies that threats might extend to real lives

Cosmic Ray in the Northern Hemisphere: Results from the Telescope Array Experiment

The Telescope Array (TA) is the largest ultrahigh energy (UHE) cosmic ray observatory in the northern hemisphere TA is a hybrid experiment with a unique combination of fluorescence detectors and a stand-alone surface array of scintillation counters. We will present the spectrum measured by the surface array alone, along with those measured by the fluorescence detectors in monocular, hybrid, and stereo mode. The composition results from stereo TA data will be discussed. Our report will also include results from the search for correlations between the pointing directions of cosmic rays, seen by the TA surface array, with active galactic nuclei.Comment: 8 pages 11 figure, Proceedings of the APS Division of Particle and Fields (DPF) Meeting, Aug 2011, Brown University, Providence, RI, US

What have we learned about primary liver transplantation under tacrolimus immunosuppression? - Long-term follow-up of the first 1000 patients

Objective: To summarize the long-term efficacy and safety of tacrolimus in orthotopic liver transplant (OLT) recipients, as well as to examine the factors that influence long-term morbidity and mortality rates. Background: Tacrolimus (FK506, Prograf) was introduced as primary immunosuppression for primary liver transplantation in 1989; many subsquent trials have verified the association of tacrolimus with decreased rates of acute rejection and steroid-resistant rejection after OLT. Cumulative experience with tacrolimus has also defined its short- and intermediate-term toxicity. Methods: One thousand consecutive patients undergoing primary OLT at a single center from August 1989 to December 1992, under tacrolimus immunosuppression, were followed until January 1999. Patients were categorized by age. Mean follow-up was 93.4 ± 11 months after OLT. Patient survival, graft survival (with corresponding causes of death and retransplantation), and rejection rates (and corresponding doses of immunosuppression) were examined as efficacy parameters. Hypertension, renal function, incidence of malignancies, incidence of diabetes, and other toxicities were examined as safety parameters. Results: Actual 6-year overall patient survival rate was 68.1% and graft survival rate was 62.5%, with significant differences in the patterns of survival among the different age groups. After the first post-OLT year, infection, recurrence of disease, de novo malignancies, and cardiovascular events were the main causes of graft loss and death during the long-term follow-up. Graft loss related to either acute or chronic rejection was rare. The rate of acute rejection beyond 2 years was approximately 3% per year, and most were steroid-responsive. Approximately 70% of the patients were receiving tacrolimus monotherapy beyond year 1; at the latest follow-up, 74.2% were maintained on tacrolimus alone. In 6.1% of the survivors, end- stage renal disease developed during the follow-up period, requiring either dialysis or kidney transplantation. Hyperkalemia and hypertension was observed in approximately one third of the patients. Insulin-dependent diabetes mellitus (including patients who had diabetes before the transplant) was observed in 14% in year 1, dropping to 11% in year 7. In 82 patients, de novo malignancies developed; in 41 patients, lymphoproliferative disorders developed during the entire follow-up period. Conclusions: Long-term patient and graft survival rates are excellent under tacrolimus immunosuppression. Pediatric patients have a better long-term outcome than adults, in part because of the limited recurrence of the original disease, which was the most common cause of late graft loss (other than patient death, most commonly the result of late de novo malignancies and cardiovascular events). Graft loss from late rejection was rare

Impurity induced density of states and residual transport in nonunitary superconductors

We obtain general expressions for the residual density of states, electrical conductivity and thermal conductivity for non-unitary superconductors due to impurity scattering. We apply the results to the so-called `B phase' of PrOs4Sb12, which we describe using a non-unitary gap function derived from symmetry considerations. The conductivity tensor has inequivalent diagonal components due to off-axis nodal positions which may be detectable in experiments.Comment: 8 pages, 1 figur

Deferring the learning for better generalization in radial basis neural networks

Proceeding of: International Conference Artificial Neural Networks — ICANN 2001. Vienna, Austria, August 21–25, 2001The level of generalization of neural networks is heavily dependent on the quality of the training data. That is, some of the training patterns can be redundant or irrelevant. It has been shown that with careful dynamic selection of training patterns, better generalization performance may be obtained. Nevertheless, generalization is carried out independently of the novel patterns to be approximated. In this paper, we present a learning method that automatically selects the most appropriate training patterns to the new sample to be predicted. The proposed method has been applied to Radial Basis Neural Networks, whose generalization capability is usually very poor. The learning strategy slows down the response of the network in the generalisation phase. However, this does not introduces a significance limitation in the application of the method because of the fast training of Radial Basis Neural Networks

Is rejection a diffuse or localized process in small-bowel transplantation?

Utilization of endoscopy to both visualize and selectively biopsy an intestinal allograft has become the standard for early recognition and treatment of intestinal allograft rejection. Despite the widespread acceptance of the need for selective mucosal biopsies, it has not been shown that the histological features of intestinal allograft rejection are either localized or occur as part of a more diffuse phenomenon within a tubular allograft. To resolve these issues, 88 ileoscopies were performed in 12 small-bowel allograft recipients and mucosal biopsy samples were obtained at 5, 10, and 15 cm, respectively, from the ileal stoma. Each mucosal biopsy was labeled, processed, and evaluated individually for the presence and severity of any evidence for allograft rejection. The data obtained suggest that intestinal allograft rejection is a diffuse process, and biopsies obtained randomly from an ileal graft are likely to demonstrate evidence of allograft rejection when such is present. © 1994 Springer-Verlag New York Inc