Analytical and experimental investigation of flow fields of annular jets with and without swirling flow

Analytical and experimental studies were performed to define the flowfield of annular jets, with and, without swirling flow. The analytical model treated configurations with variations of flow angularities, radius ratio, and swirl distributions. Swirl distributions characteristic of stator vanes and rotor blade rows, where the total pressure and swirl distributions are related were incorporated in the mathematical model. The experimental studies included tests of eleven nozzle models, both with and, without swirling exhaust flow. Flowfield surveys were obtained and used for comparison with the analytical model. This comparison of experimental and analytical studies served as the basis for evaluation of several empirical constants as required for application of the analysis to the general flow configuration. The analytical model developed during these studies is applicable to the evaluation of the flowfield and overall performance of the exhaust of statorless lift fan systems that contain various levels of exhaust swirl

Triple correlation for detection of damage-related nonlinearities in composite structures

Nonlinear effects in vibration responses are investigated for the undamaged composite plate and the composite plate with a delamination. The analysis is focused on higher harmonic generation in vibration responses for various excitation amplitude levels. This effect is investigated using the triple correlation technique. The dynamics of composite plate was modelled using two-dimensional finite elements and the classical lamination theory. The doubled-node approach was used to model delamination area. Mode shapes and natural frequencies were estimated based on numerical models. Next, the delamination divergence analysis was used to obtain relative displacements for delaminated plies. Experimental modal analysis test was carried out to verify the numerical models. The two strongest vibration modes as well as two vibration modes with the smallest and largest motion level of delaminated plies were selected for nonlinear vibration test. The Fisher criterion was employed to verify the effectiveness and confidence level of the proposed technique. The results show that the method can be used not only to reveal nonlinearities, but also to reliably detect impact damage in composites. These results are confirmed using the statistical analysis

Die pyloruserhaltende Whipple-Operation: eine Alternative oder heutiger Standard beim Pankreaskarzinom?

Zusammenfassung: Grundlagen: Während die pyloruserhaltende Whipple-Operation eine gute Alternative zur klassischen Operation bei periampullären Tumoren darstellt, ist das Verfahren beim Pankreaskopfkarzinom umstritten. Methodik: Wir haben die Daten von 70 Patienten mit Pankreaskopfkarzinom prospektiv im Hinblick auf die Vorteile des operativen Vorgehens und in bezug auf Lebensqualität und Überlebenszeit untersucht. Ergebnisse: Bei 44 Patienten wurde eine pyloruserhaltende Resektion durchgeführt, bei 26 Fällen eine klassische Whipple-Operation (WO) mit Lymphadenektomie. Es gab bezüglich Alter, Geschlecht und Tumorstadium keine Unterschiede in den beiden Patientengruppen. Die Mittelwerte für die Operationszeit, Blutverlust und Hospitalisationsdauer betrugen bei der pyloruserhaltenden WO 382 min, 1125 ml und 18,3 Tage und bei der klassischen WO 460 min (p<0,05), 1650 ml (p<0,05) und 22 Tage. Die mediane Überprüfzeit betrug 17 Monate (Range 2 bis 28 Monate). In den ersten 3 Monaten postoperativ war der Gewichtsverlauf bei den Patienten mit pyloruserhaltender WO deutlich besser. Die mediane Überlebenszeit war nicht signifikant verschieden mit 12,2 Monaten für die Patienten mit pyloruserhaltender WO und 12,9 Monaten bei den Patienten mit klassischer WO. Schlußfolgerungen: Bei Patienten mit Pankreaskarzinom war die Lebensqualität und Gewichtszunahme postoperativ besser bei solchen mit pyloruserhaltender partieller Duodenopankreatektomie im Vergleich zur klassischen WO. Aufgrund dieser Ergebnisse, der intraoperativen Vorteile und bei gleicher Überlebenszeit sollte dieses Operationsverfahren beim Pankreaskarzinom, wenn immer möglich, bevorzugt werde

Pancreatic Resections for Advanced M1-Pancreatic Carcinoma: The Value of Synchronous Metastasectomy

Background. For M1 pancreatic adenocarcinomas pancreatic resection is usually not indicated. However, in highly selected patients synchronous metastasectomy may be appropriate together with pancreatic resection when operative morbidity is low. Materials and Methods. From January 1, 2004 to December, 2007 a total of 20 patients with pancreatic malignancies were retrospectively evaluated who underwent pancreatic surgery with synchronous resection of hepatic, adjacent organ, or peritoneal metastases for proven UICC stage IV periampullary cancer of the pancreas. Perioperative as well as clinicopathological parameters were evaluated. Results. There were 20 patients (9 men, 11 women; mean age 58 years) identified. The primary tumor was located in the pancreatic head (n = 9, 45%), in pancreatic tail (n = 9, 45%), and in the papilla Vateri (n = 2, 10%). Metastases were located in the liver (n = 14, 70%), peritoneum (n = 5, 25%), and omentum majus (n = 2, 10%). Lymphnode metastases were present in 16 patients (80%). All patients received resection of their tumors together with metastasectomy. Pylorus preserving duodenopancreatectomy was performed in 8 patients, distal pancreatectomy in 8, duodenopancreatectomy in 2, and total pancreatectomy in 2. Morbidity was 45% and there was no perioperative mortality. Median postoperative survival was 10.7 months (2.6–37.7 months) which was not significantly different from a matched-pair group of patients who underwent pancreatic resection for UICC adenocarcinoma of the pancreas (median survival 15.6 months; P = .1). Conclusion. Pancreatic resection for M1 periampullary cancer of the pancreas can be performed safely in well-selected patients. However, indication for surgery has to be made on an individual basis

Ultrasonic Scan Control and Analysis Using Catia Datasets

There has been a proliferation in the use of polymer composite parts in aircraft structural applications. Designers also are using more computer-aided design (CAD) tools to define and manufacture such parts. Computer-Graphics Aided Three-Dimensional Interactive Application (CATIA) software was developed by Dassault Systemes and is used at The Boeing Company to design new composite parts. A part’s construction is often complicated by material, thickness, or profile variations that are required by engineering specifications. When complex composite parts are fabricated, it is often necessary to perform nondestructive evaluation to determine a part’s interior quality. Automated ultrasonic inspection is a common method used on composite laminate and honeycomb parts. The typical system output consists of one or more C-Scan images on a computer display

Level of Patient-Physician Agreement in Assessment of Change Following Conservative Rehabilitation for Shoulder Pain

Background Assessment of health-related status has been shown to vary between patients and physicians, although the degree of patient–physician discordance in the assessment of the change in status is unknown. Methods Ninety-nine patients with shoulder dysfunction underwent a standardized physician examination and completed several self-reported questionnaires. All patients were prescribed the same physical therapy intervention. Six weeks later, the patients returned to the physician, when self-report questionnaires were re-assessed and the Global Rating of Change (GROC) was completed by the patient. The physician completed the GROC retrospectively. To determine agreement between patient and physician, intra-class correlation (ICC) coefficient and Pearson’s r using the 15-point GROC and weighted kappa using a consolidated three-point GROC were calculated. Results Utilizing the 15-point GROC, complete agreement was observed in 37 of 99 patients (37%). ICC and Pearson’s r between patient and physician were 0.62 and 0.63, respectively. Utilizing a consolidated three-point GROC, complete agreement was observed in 76 of 99 patients (77%). Weighted kappa was 0.62. Conclusions Assessment of change reported by the patient demonstrates moderate to good agreement with physician assessment. These findings indicate that the GROC does reflect and represent similar assessment of change in health status by patients and physicians. This can aid discussion of both past treatment results and future treatment plans

Descriptive Analysis of Common Functional Limitations Identified by Patients with Shoulder Pain

Context: Recent establishment of G-codes by the US government requires therapists to report function limitations at initial evaluation. Limited information exists specific to the most common limitations in patients with shoulder pain. Objective: To describe the most commonly expressed shoulder limitations with activities and their severity/level of impairment from a patient’s perspective on the initial evaluation. Design: Descriptive. Setting: Patients reporting pain with overhead activity and seeking medical attention from one orthopedic surgeon were recruited as part of a cohort study. Patients: 176 with shoulder superior labral tear from anterior to posterior (SLAP), subacromial impingement, combined SLAP and rotator cuff, and nonspecific (female = 53, age = 41 ± 13 y; male = 123, age = 41 ± 12 y). Interventions: Data were obtained on the initial visit from the Patient-Specific Functional Scale (PSFS) questionnaire. Three researchers extracted meaningful concepts from the PSFS and linked them to the International Classification of Functioning (ICF) categories according to established ICF linking rules. Results: 176 participants yielded 765 meaningful concepts that were linked to the ICF with a 66% agreement between researchers before consensus. There were no differences between diagnoses. Of all patients, 88% reported functional limitations coded into meaningful concepts as represented by 10 ICF codes; 634 (83%) meaningful concepts were linked to the activities and participation domain while 129 (17%) were linked to the body function domain. Only 2 reported functional limitations that were considered nondefinable (nd). The overall average initial impairment score on the PSFS = 4 ± 2.5 out of 10 points. Conclusion: Meaningful concepts from the activities and participation domain were most commonly identified as functional limitations and were more prevalent than limitations from the body function domain. This information helps identify some of the most common limitations in patients with shoulder pain that therapists can use to efficiently document patient functional impairment

Reliability of an Observational Method Used to Assess Tennis Serve Mechanics in a Group of Novice Raters

Background: Previous research has developed an observational tennis serve analysis (OTSA) tool to assess serve mechanics. The OTSA has displayed substantial agreement between the two health care professionals that developed the tool; however, it is currently unknown if the OTSA is reliable when administered by novice users. Purpose: The purpose of this investigation was to determine if reliability for the OTSA could be established in novice users via an interactive classroom training session. Methods: Eight observers underwent a classroom instructional training protocol highlighting the OTSA. Following training, observers participated in two different rating sessions approximately a week apart. Each observer independently viewed 16 non-professional tennis players performing a first serve. All observers were asked to rate the tennis serve using the OTSA. Both intra and inter-observer reliability were determined using Kappa coefficients. Results: Kappa coefficients for intra and inter-observer agreement ranged from 0.09 to 0.83 depending on the body position. A majority of all body positions yeilded moderate agreement and higher. Conclusion: This study suggests that the majority of components associated with the OTSA are reliable and can be taught to novice users via a classroom training session

Magnons in real materials from density-functional theory

We present an implementation of the adiabatic spin-wave dynamics of Niu and Kleinman. This technique allows to decouple the spin and charge excitations of a many-electron system using a generalization of the adiabatic approximation. The only input for the spin-wave equations of motion are the energies and Berry curvatures of many-electron states describing frozen spin spirals. The latter are computed using a newly developed technique based on constrained density-functional theory, within the local spin density approximation and the pseudo-potential plane-wave method. Calculations for iron show an excellent agreement with experiments.Comment: 1 LaTeX file and 1 postscript figur