Energy efficient engine sector combustor rig test program

Under the NASA-sponsored Energy Efficient Engine program, Pratt & Whitney Aircraft has successfully completed a comprehensive combustor rig test using a 90-degree sector of an advanced two-stage combustor with a segmented liner. Initial testing utilized a combustor with a conventional louvered liner and demonstrated that the Energy Efficient Engine two-stage combustor configuration is a viable system for controlling exhaust emissions, with the capability to meet all aerothermal performance goals. Goals for both carbon monoxide and unburned hydrocarbons were surpassed and the goal for oxides of nitrogen was closely approached. In another series of tests, an advanced segmented liner configuration with a unique counter-parallel FINWALL cooling system was evaluated at engine sea level takeoff pressure and temperature levels. These tests verified the structural integrity of this liner design. Overall, the results from the program have provided a high level of confidence to proceed with the scheduled Combustor Component Rig Test Program

Retrospektivna analiza graničnih tumora jajnika: ishodi u jednom centru

We wanted to discuss our experiences in the approach to borderline ovarian tumors, which constitute a group different from epithelial ovarian tumors with respect to their biological structure in line with retrospective information gathered from our cases. A total of 25 patients operated on for the indication of adnexal masses diagnosed as borderline ovarian tumors based on frozen section results were included in our study. Patient age, tumor diameter, tumor markers and surgeries performed were discussed in the light of the literature. Statistical analyses were performed using the SPSS software. The patient mean age was 43.84±11.34 years. The mass was localized in the right (n=13), left (n=11) or both (n=1) adnexal regions. The mean tumor diameter was 12.9±5.84 cm. Histopathologic examination established the diagnosis of serous borderline (n=14 patients) and mucinous borderline (n=11) ovarian tumors. Although the results of our study are consistent with current literature data, a greater number of current studies should be performed on borderline ovarian tumors, which are defined as a class of tumors different from epithelial ovarian tumors.Želja nam je opisati naša iskustva u pristupu graničnim tumorima jajnika kao skupini tumora koji se razlikuju od epitelnih tumora jajnika prema biološkoj strukturi, sukladno retrospektivnim podacima prikupljenim iz naših slučajeva. U istraživanje je bilo uključeno 25 bolesnica operiranih pod indikacijom adneksnih tvorevina dijagnosticiranih kao granični tumori jajnika na osnovi rezultata dobivenih iz zamrznutih uzoraka. Prikazani su sljedeći podaci bolesnica: dob, promjer tumora, tumorski biljezi i izvedeni operativni zahvati, u odnosu na literaturne podatke. Statistička analiza je provedena primjenom programa SPSS. Srednja dob bolesnica bila je 43,84±11,34 godine. Tumorska masa bila je smještena u desnoj (n=13) ili lijevoj (n=11) adneksnoj regiji, a kod jedne bolesnice u objema adneksnim regijama. Srednji promjer tumora bio je 12,9±5,84 cm. Histopatološkom analizom postavljena je dijagnoza seroznog graničnog (n=14) i mucinoznog graničnog (n=11) tumora jajnika. Iako su rezultati ovoga istraživanja sukladni literaturnim podacima, potrebno je provesti veći broj studija graničnih tumora jajnika, koji se definiraju kao vrsta tumora različita od epitelnih tumora jajnika

Surgical management of nonobstructive azoospermia

Nonobstructive azoospermia (NOA) is characterized by the complete absence of sperm in the ejaculate due to testicular failure. The evaluation and management of patients with NOA offer a challenge to the reproductive urologist. In the era of in vitro fertilization with intracytoplasmic sperm injection, surgical sperm extraction techniques can afford men with NOA biologic paternity. To provide a comprehensive review of surgical sperm retrieval approaches in the patient with NOA emphasizing complications, success rates and outcome optimization, a Medline search was conducted querying surgical approaches used to manage NOA. Four sperm extraction techniques are described including: testicular sperm aspiration, testicular sperm extraction, fine needle aspiration mapping and microdissection testicular sperm extraction. In addition, the roles for pre-extraction varicocelectomy and sperm cryopreservation are discussed. The management of NOA continues to evolve as newer tools become available. Several modalities of sperm acquisition exist. An understanding of their complications and success rates is fundamental to the treatment of NOA

Severe male infertility after failed ICSI treatment-a phenomenological study of men's experiences

<p>Abstract</p> <p>Background</p> <p>Male-factor infertility underlies approximately 30% of infertility in couples seeking treatment; of which 10% is due to azoospermia. The development of assisted reproductive technology (ART), enabling the use of epididymal or testicular sperm for fertilization of the partner's oocytes, has made biological fatherhood possible for men with obstructive azoospermia. There is limited knowledge of men's experience of their own infertility. The aim of this study was to describe men's experiences of obstructive azoospermia infertility.</p> <p>Methods</p> <p>Eight men with obstructive azoospermia, who had terminated Swedish public health system ART treatment two years previously without subsequent childbirth, were interviewed using a descriptive phenomenological method.</p> <p>Results</p> <p>The essence of the phenomenon is expressed with a metaphor: climbing a mountain step by step with the aim of reaching the top, i.e. having a child and thus a family with a child. Four constituents are included (1) inadequacy followed by a feeling of redress (2) marginalisation, (3) chivalry (4) extension of life and starting a family as driving forces.</p> <p>Conclusions</p> <p>Knowledge of men's experiences of their own infertility is important as a supporting measure to increase the quality of care of infertile couples. By adopting this facet of gender perspective in fertility treatment guidelines, care can hopefully be optimized.</p

Determinants of visual size constancy in different orientations in light and darkness

This project was concerned with the perception of size constancy of simple, elongated and planar objects in the light and dark. The main findings are: transverse, vertical and medial axes give rise to different degrees of size constancy; true size and shape of the objects proved to be a factor in size constancy; the size-distance invariance hypothesis (SDIH) cannot explain underconstancy in the light, and perfect constancy in the dark

A Stochastic Approach to the Assembly Line Balancing Problem

165 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1971.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD

Experimental research on in-tube condensation under steady-state and transient conditions

In this research study, in-tube condensation in the presence of air was investigated experimentally at a heat exchanger of countercurrent type for different operating conditions. The test matrix for the steady-state condition covers the range of pressures P = 1.8 to 5.5 bars, vapor Reynolds numbers Re, = 45 000 to 94 000, and inlet air mass fraction values Xi = 0 to 52%. The effect of air manifests itself by a reduction in the local heat flux and the local heat transfer coefficient. The local heat transfer coefficient is inversely proportional to the local air mass fraction. Both the local heat flux and the heat transfer coefficient vary with the system pressure and vapor mass flow rate. There is no effect of inlet superheating on the local heat flux. The film Reynolds number lies in the range of the turbulent region. Two experiments simulating loss of coolant to the secondary side of the condenser were performed, for pure steam and for an air/steam mixture. These transients show that the vapor suction rate, effective condensation length, and overall heat transfer rate are a function of the coolant boiloff rate and the air mass fraction