bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of the number of enlarged pores according to site, age, and sex
Authors: Jung H.J. , Ahn J.Y. , Lee J.I. , Bae J.Y. , Kim H.L. , Suh H.Y. , Youn J.I. , Park M.Y. 
Published: February 2018

AbstractBackgroundIncreasing the number of enlarged pores causes cosmetic problems. The difference in the number of enlarged pores according to facial site, age, and sex is unclear.ObjectiveTo analyze the distribution of the number of enlarged pores according to facial site, age, and sex.Methods and materialsWe analyzed the number of the enlarged pores and the percentage of wrinkles in the nose, forehead, and cheek from 434 polarized images. The measurement results were analyzed according to site, age, and sex. Relationship between enlarged pore counts and wrinkle severity was also analyzed. The study was conducted by using DermaVision,™ which can take cross‐polarization, parallel polarization, and ultraviolet light images.ResultsThe enlarged pores of the nose and forehead were more prominent than in the cheeks. Pore counts were increased with age, and the increment was significant between the 30's and 40's. There was no significant difference by gender. Enlarged pore counts were related to wrinkle severity.ConclusionsThe number of enlarged pores differs depending on body site and increased with age. The enlarged pore counts correlate with wrinkle severity and the correlation varies depending on the body site.
Correcting preoperative iron deficiency as part of patient blood management in the ‘real world’: results of an audit on an Australian cohort
Authors: Hong F. S. , Sieradzki N. , Pollock C. , Nasra F. , Churilov L. , Mo A. , Willcox A. , Ho W. K. , Smith C. 
Published: February 2018

BackgroundThe perioperative module of the Australian Patient Blood Management guidelines recommended preoperative iron therapy for surgical patients with, or at risk of, iron deficiency anaemia. After implementing a preoperative haemoglobin optimization programme in our institution, an audit was undertaken to evaluate the benefit of preoperative iron therapy in ‘real world’ clinical practice.MethodsElective major surgery patients assessed in surgical pre‐admission clinics from 1 July 2013 to 30 June 2014 were screened for iron deficiency and anaemia. Those who were iron deficient (ferritin <30 μg/l), regardless of haemoglobin level, received either daily oral iron supplementation until day of surgery or intravenous iron polymaltose 1 g preoperatively (intervention group). Control patients who were not iron deficient were matched to the intervention group using propensity scores based on age, sex and surgical unit. The primary end‐point was the proportion of patients requiring perioperative red cell transfusion in intervention and control groups.ResultsOne hundred and fourteen patients (8·75%) had iron deficiency. Ninety‐three patients received preoperative iron therapy, 17 (18·3%) of whom required red cell transfusions postoperatively. Of the 332 control patients, 71 (21·4%) required red cell transfusion. After adjusting for preoperative haemoglobin and time from screening to surgery, the odds of red cell transfusion were significantly lower in the intervention group compared to controls (odds ratio: 0·512, 95% confidence interval: 0·268–0·977; P = 0·04).ConclusionPreoperative iron therapy was associated with reduced need for postoperative red blood cell transfusion in elective major surgery patients who were initially iron deficient.
Turbomachinery-Based Vapor Pressure Amplifier for Refrigeration Energy Saving
Authors: Chennaoui Leila , Cerri Giovanni , Alavi Sayyedbenyamin 
Published: February 2018

Vapor compression refrigeration plant power consumption can be heavily reduced for a definite cooling power by the adoption of a power regeneration process internal to the simple cycle. Such a process takes benefit from the adoption of turbomachinery based vapor pressure amplifier.
The selection of the wheel sizes, their machining to be adapted to the process and the addition of stator blades in the expander and a diffuser in the compressor path is discussed and tests results are presented.
Improvements of the power consumption and of the COP of about 23–24% for a specified cooling power have been demonstrated.
Development of LP Blade Module for High Back Pressure-Aerodynamic Design
Authors: Ambrish  , Singh Nand Kumar 
Published: February 2018

In steam turbine power plants, the appropriate design of the last stage blades is critical in determining the plant efficiency and reliability. The development of LP module for desert applications is finding applications for a number of industrial steam turbine operating with air cooled condensers. The conventional LP Module for water cooled condenser operates at low back pressure (Pexit = 0.09 bar) and are generally not suitable for high back pressure application. This paper focuses on the aerodynamic design & optimization of last stages of LP blade module for high back pressure application and validation through 3D CFD. The guide and moving blade are designed with seven equally-spaced profiles section from hub to shroud through Axstream S/w. The profile and incidence losses are minimized for the design and off-design conditions.
Aeromechanical design of LP blade module consisting of 2 stages for 0.2 bar back pressure, 1.1 bar inlet static pressure and a mass flow of 61.2 kg/s is carried out. An optimization process through a streamline curvature code and design optimization software using Optimus is established and flow path contours is optimized thoroughly, a total to total efficiency of 81.4% is achieved for the rated condition. The off-design performance is investigated for a wide range of operating conditions, especially at low volume flow rate of steam condition.
Surrogate Based Design Optimisation of Combustor Tile Cooling Feed Holes
Authors: Nagabandi K. , Mills S. , Zhang X. , Toal D. J. J. , Keane A. J. 
Published: February 2018

Gas turbine operating temperatures are projected to continue to increase and this leads to drawing more cooling air to keep the metals below their operational temperatures. This cooling air is chargeable as it has gone through several stages of compressor work. In this paper a surrogate based design optimization approach is used to reduce cooling mass flow on combustor tiles to attain pre-defined maximum metal surface temperatures dictated by different service life requirements.
A series of Kriging based surrogate models are constructed using an efficient GPU based particle swarm algorithm. Various mechanical and manufacturing constraints such as hole ligament size, encroachment of holes onto other features like side rails, pedestals, dilution ports and retention pins etc. are built into the models and these models are trained using a number of high fidelity simulations. Furthermore these simulations employ the proprietary Rolls-Royce Finite Element Analysis (FEA) package SCO3 to run thermal analysis predicting surface heat transfer coefficients, fluid temperatures and finally metal surface temperatures.
These temperature predictions are compared against the pre-defined surface temperature limits for a given service life and fed back to the surrogate model to run for new hole configuration. This way the loop continues until an optimized hole configuration is attained. Results demonstrate the potential of this optimization technique to improve the life of combustor tile by reducing tile temperature and also to reduce the amount of cooling air required.
Flashback and Lean Blow Out Study of a Lean Premixed Pre-Vaporized Can Combustor
Authors: Verma Harendra K. , Kumar Arvind , Kumar Keshav , Mohammed Rinaz 
Published: February 2018

The latest trend in aero engine industry is to reduce the emission levels to a maximum extent as well as to improve the combustion efficiency. One of the ways to reduce the emission levels and improve the combustion efficiency in gas turbine combustors is to operate with lean premixed conditions. However, design modifications are required in conventional combustors to operate at lean premixed conditions.
A new combustor configuration was studied for lean premixed pre-vaporized (LPP) combustion. To arrive at LPP configuration a simple gas turbine Can-combustor geometry is modified by attaching a fuel air premixer chamber at upstream of the flame tube of basic diffusion combustor [1]. Reactive flow analysis was performed with both the LPP and conventional diffusion combustor using commercial CFD tool Fluent. Significant improvements were obtained from LPP combustor in terms of emission reduction. However, there are limitations for lean burning of fuel such as flashback and lean blow out. Present work is focused on studying these issues on the LPP combustor. These methodologies can be extended for other type of combustors after further studies.
Application of Cold Expansion Process to Dovetail Slots of Compressor Disc: A Numerical Study
Authors: Kumar Sudhakar Anil , Babu Neelakantanahally Channaiah Mahendra 
Published: February 2018

Dovetail slots are essential structural cut-outs made in compressor disc to assemble blades. Under in-service centrifugal loading and inherent vibrations, the root regions of these dovetail slots are prone to fatigue failures. Surface treatment methods like shot peening, low plasticity burnishing and laser shock peening are employed to achieve fatigue life extension of dovetail slots. Another method commonly employed in aerospace industry for fatigue life extension of circular holes is the cold expansion process. This cold expansion process is a proven surface treatment method capable of achieving highest fatigue life enhancement benefits compared to other surface treatment methods, particularly for circular holes. Considering the efficacy of circular hole cold expansion process, an attempt is made in this work to study the suitability of cold expansion process for dovetail slots.
In this work, a three dimensional, non-linear Finite Element simulation has been carried out to explore the application of cold expansion process for dovetail slot of a compressor disc. This Finite Element simulation involves two main steps namely, cold expansion of holes and machining process between holes. Two circular holes of appropriate radius at root locations of dovetail slot are cold expanded to introduce beneficial compressive residual stresses and further, portion between the two holes is machined-off to obtain the required dovetail shape. Complete distributions of beneficial compressive residual stresses retained after machining of dovetail slot are captured to assess the efficacy of cold expansion. The predicted results indicate that the proposed cold expansion process for dovetail slots is capable of significantly enhancing the fatigue life of dovetail slots.
Sub Modeling in Dynamic Analysis
Authors: Devadoss Gnanaraj , Thokala Anil , Kumar Avinash , Bysani Prasanth Kumar 
Published: February 2018

In design of components, it is more convenient to analyze the component alone by modeling all the interface loads / displacements as boundary conditions rather than modeling the entire assembly. This process of analyzing at component level is referred as sub model analysis. Most of the assembly level model consists of several components and each component may have different owners. In cases where the entire assembly level model cannot be shared with component owners due to confidentiality, Sub model analysis is the preferred approach. Sub-model analysis also reduces overall model size and in turn the solution time.
Sub modeling is widely used approach in static structural analysis. In dynamic analysis, response of any system is a function of its stiffness, damping and inertia properties along with the applied loads. Sub model will have different inertia, stiffness and damping representations when compared with the assembly level model (also known as full model). The effect of these differences on sub model responses compared to full model needs to be investigated to validate sub modeling approach in dynamic analysis.
In this paper it is shown mathematically and also using finite element analyses that the dynamic response of a component is same between sub-model analysis and full model analysis. In sub-model analysis, dynamic behavior of the remaining system is captured by applying interface loads at component interfaces (with remaining model) which in turn is obtained from full model analysis. Frequency domain finite element model with harmonic excitations is considered to validate the sub modeling approach in dynamic analysis. The observations and conclusions inferred from this frequency domain analysis are also applicable for time domain analysis.
This study is carried out using MSC Nastran.
Reliability of Ti/SiC Metal Matrix Composites
Authors: Mishra Ashish , Mahesh Sivasambu 
Published: February 2018

Components such as bladed rings, and bladed disks fabiricated out of titanium matrix composites were extensively explored in the two decades since about 1990 as light weight replacements for conventional superalloy blades and disks in the intermediate hot stages of gas turbines. One of the challenges, which has hindered their adoption is the relative unreliability of the composite components; nominally identical Ti composite specimen display a much larger variability in strength than their superalloy counterparts.
In the present work, we have quantified the reliability of Ti matrix composites by developing a detailed micromechanical-statistical model of their failure. The micromechanical model resolves fibres, matrix, and the interface, and accounts for such failure modes as fibre breakage, matrix cracking, matrix plasticity, interfacial sliding, and debonding. It also accounts for mechanical interaction between these various failure modes. The mechanical model’s predictions are validated against synchotron X-ray measurements reported in the literature, both after loading, and unloading. Using the detailed micromechanical model, Ti matrix composite was simulated following a Monte Carlo framework. These simulations yield the empirical strength distribution of the Ti matrix composite, and insights into the dominant failure mode. The latter allows the construction of a stochastic model of composite failure. The stochastic model can be used to determine safe working loads as a function of composite size for any desired reliability level.
Suction Mode Start Characteristics of a Turbofan Engine for a Windmill Relight
Authors: Bhatt Ashish , Balaji B. , Tyeb Abdullah , Gupta Amit , Padwale Mahesh P. , Ravishankar G. P. 
Published: February 2018

Wind-milling occurs when air flowing through the flamed out engine results in increasing spool rotation. Aircraft forward speed and dive angles play an important role in achieving sustainable spool rotation for relight. Aircraft fuel pump connected to power take-off shaft of Engine shuts when engine rpm falls below design speed and cannot deliver pressurized fuel to Engine during wind-milling. Under this condition, engine has to suck the fuel from aircraft using its own fuel pump. The atmospheric pressure available on the aircraft fuel tank assists the engine to operate in suction mode. The datum height between engine inlet and fuel tank outlet changes with the dive angle of the aircraft.
A test set up was established in the engine test bed to vary the datum between aircraft fuel tank and Engine inlet. The datum was varied to simulate various dive angles of the aircraft. The negative gravity head (Engine fuel inlet above fuel tank outlet) between engine and fuel tank was varied in steps. Total four test cases were carried out in an engine test bed located at an altitude of 920 m above sea level. The engine was successfully started in suction mode without external assistance of fuel pump. This paper presents the test setup, comparison of engine start cycle under various dive angles of the aircraft to evaluate optimum flight conditions to attempt windmill relight.
These tests show that as the negative gravity head is increased, the time taken to start the engine increases. The slope of N2 build up becomes shallower with increase in gravity head.
The Unstructured Paramyxovirus Nucleocapsid Protein Tail Domain Modulates Viral Pathogenesis through Regulation of Transcriptase Activity
Authors: Thakkar Vidhi D. , Cox Robert M. , Sawatsky Bevan , da Fontoura Budaszewski Renata , Sourimant Julien , Wabbel Katrin , Makhsous Negar , Greninger Alexander L. , von Messling Veronika , Plemper Richard K. 
Published: February 2018

ABSTRACT

The paramyxovirus replication machinery comprises the viral large (L) protein and phosphoprotein (P-protein) in addition to the nucleocapsid (N) protein, which encapsidates the single-stranded RNA genome. Common to paramyxovirus N proteins is a C-terminal tail (Ntail). The mechanistic role and relevance for virus replication of the structurally disordered central Ntail section are unknown. Focusing initially on members of the
Morbillivirus
genus, a series of measles virus (MeV) and canine distemper virus (CDV) N proteins were generated with internal deletions in the unstructured tail section. N proteins with large tail truncations remained bioactive in mono- and polycistronic minireplicon assays and supported efficient replication of recombinant viruses. Bioactivity of Ntail mutants extended to N proteins derived from highly pathogenic Nipah virus. To probe an effect of Ntail truncations on viral pathogenesis, recombinant CDVs were analyzed in a lethal CDV/ferret model of morbillivirus disease. The recombinant viruses displayed different stages of attenuation ranging from ameliorated clinical symptoms to complete survival of infected animals, depending on the molecular nature of the Ntail truncation. Reinfection of surviving animals with pathogenic CDV revealed robust protection against a lethal challenge. The highly attenuated virus was genetically stable after
ex vivo
passaging and recovery from infected animals. Mechanistically, gradual viral attenuation coincided with stepwise altered viral transcriptase activity in infected cells. These results identify the central Ntail section as a determinant for viral pathogenesis and establish a novel platform to engineer gradual virus attenuation for next-generation paramyxovirus vaccine design.

IMPORTANCE
Investigating the role of the paramyxovirus N protein tail domain (Ntail) in virus replication, we demonstrated in this study that the structurally disordered central Ntail region is a determinant for viral pathogenesis. We show that internal deletions in this Ntail region of up to 55 amino acids in length are compatible with efficient replication of recombinant viruses in cell culture but result in gradual viral attenuation in a lethal canine distemper virus (CDV)/ferret model. Mechanistically, we demonstrate a role of the intact Ntail region in the regulation of viral transcriptase activity. Recombinant viruses with Ntail truncations induce protective immunity against lethal challenge of ferrets with pathogenic CDV. This identification of the unstructured central Ntail domain as a nonessential paramyxovirus pathogenesis factor establishes a foundation for harnessing Ntail truncations for vaccine engineering against emerging and reemerging members of the paramyxovirus family.
Preoperative exercise halves the postoperative complication rate in patients with lung cancer: a systematic review of the effect of exercise on complications, length of stay and quality of life in patients with cancer
Authors: Steffens Daniel , Beckenkamp Paula R , Hancock Mark , Solomon Michael , Young Jane 
Published: February 2018

ObjectiveTo investigate the effectiveness of preoperative exercises interventions in patients undergoing oncological surgery, on postoperative complications, length of hospital stay and quality of life.DesignIntervention systematic review with meta-analysis.Data sourcesMEDLINE, Embase and PEDro.Eligibility criteria for selecting studiesTrials investigating the effectiveness of preoperative exercise for any oncological patient undergoing surgery were included. The outcomes of interest were postoperative complications, length of hospital stay and quality of life. Relative risks (RRs), mean differences (MDs) and 95% CI were calculated using random-effects models.ResultsSeventeen articles (reporting on 13 different trials) involving 806 individual participants and 6 tumour types were included. There was moderate-quality evidence that preoperative exercise significantly reduced postoperative complication rates (RR 0.52, 95% CI 0.36 to 0.74) and length of hospital stay (MD −2.86 days, 95% CI −5.40 to −0.33) in patients undergoing lung resection, compared with control. For patients with oesophageal cancer, preoperative exercise was not effective in reducing length of hospital stay (MD 2.00 days, 95% CI −2.35 to 6.35). Although only assessed in individual studies, preoperative exercise improved postoperative quality of life in patients with oral or prostate cancer. No effect was found in patients with colon and colorectal liver metastases.ConclusionsPreoperative exercise was effective in reducing postoperative complications and length of hospital stay in patients with lung cancer. Whether preoperative exercise reduces complications, length of hospital stay and improves quality of life in other groups of patients undergoing oncological surgery is uncertain as the quality of evidence is low.PROSPEROregistration number
Varying levels of fidelity on psychomotor skill attainment: a CORTRAK product assessment
Authors: Gonzalez Laura , Bourgault Annette M , Aguirre Lillian 
Published: February 2018

BackgroundA task trainer is defined as a model that represents a part or region of the human body such as an arm and an abdomen… generally used to support procedural skills training. Concepts for consideration when selecting a task trainer include fidelity and cognitive load. Insertion of small - bore FTs in acutely ill patients continues to be a high - risk skill. The most frequent complication is insertion of the F T into the pulmonary system, which can lead to pneumothorax, pneumonitis and death. Training consists of placing the FT under electromagnetic visual assistance in a task trainer.ObjectiveThis study describes assessment of two task trainers that are used to simulate assisted feeding tube (FT) insertion. Simulation is an excellent approach to close the learning gap and ensure competency. Study selection: This study used a prospective observational design. Participants (n=20) were registered nurses considered to be superusers. They were randomly assigned to order of the task trainer.Findings and conclusionsThe findings suggest the learners preferred the low-fidelity task trainer. The clear Anatomical Box scored higher overall (18.35/21) when compared with the human-like task trainer (16.5/21). A higher fidelity task trainer may seem attractive; however, with a lens to cognitive load theory, it may hinder the early learning process. Fidelity requirements vary depending on the training task. Recommendations from this study include: initial instruction should focus on the psychomotor steps for the FT insertion process. The high-fidelity human torso is recommended for performance, final competency and ongoing competency maintenance.