bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhancement of Wind Turbine Aerodynamic Performance Using New Designed Airfoils
Authors: Kedam Naresh , Nakka Sudhakar , Baloni Beena D. , Channiwala S. A. 
Published: February 2016

The rotor is the first element in the chain of functional elements of a wind turbine. Therefore, its aerodynamic and dynamic properties have a decisive influence on the entire system in many respects. The capability of the rotor to convert a maximum proportion to the wind energy, flowing through its swept area, into mechanical energy is obviously the direct result of its aerodynamic properties. These will determine the overall efficiency of the energy conversion in the wind turbine. To enhance the performance of wind turbine, one has to analyze the effects of variations in nomenclature of a rotor blade on the performance of wind turbine.
The present paper incorporates the analysis of primary selected blade design by the Solar Energy Research Institute (SERI -8) with BEMT based simulations; five different suggested models of the rotor blade are also analyzed with same BEM based simulations, including Tip losses, 3-D corrections and Reynolds number drag correction. These six models incorporate twist optimization, chord distribution optimization, and the combination of airfoils, new designed airfoils and base model SERI-8 rotor blade. Without modifying the size of the rotor blade, different analysis is done and improved the rotor aerodynamics efficiency. Highly aerodynamics efficient new designed airfoils produce more lift and minimize the drag by avoiding the stall; it develops high-value of coefficient of lift to drag (Cl/Cd) ratio. The rated power for all models considered at 15m/s for analysis. The result suggests that the rotor power efficiency is 25.772% with SERI-8, 29.420% with the twist optimized model, 55.51% with the model with a combination of SG series and SERI series airfoils and 61.62% with new designed airfoils (SV Series) model. Respectively, efficiency is increased by 3.64%, 29.745%, and 35.84% compared to SERI-8 blade.
Suppression of Combustion Noise in Gas Turbine Combustors
Authors: Kumar Juvva Srihari Dinesh , Mariappan Sathesh , Kushari Abhijit 
Published: February 2016

This study deals with the investigations on the sources and the control of combustion noise, in an atmospheric gas turbine combustor. Combustion noise encountered here is also termed as hooting, as it occurs within a limited bandwidth of frequencies ranging from 300–450 Hz. Combustion noise is usually classified as direct and in-direct combustion noise. The present study emphases on the direct combustion noise which occurs when a volume of gas expands at constant pressure, as soon as it is heated by combustion; this results in a sound wave which propagates outside the boundary of the flame. At certain conditions, if the unsteady heat release rate drives the acoustic oscillations, satisfying Rayleigh criterion, pressure oscillations grow leading to discrete tonal sound and this phenomena is termed as combustion instability.
Experiments are conducted in a liquid fuelled swirl stabilized atmospheric gas turbine combustor, whose aspect ratio is 2.5, combustion intensity varies from 25MW/m3 atm to 50MW/m3 atm. Air is passed through various stages: primary, secondary, quenching and atomizing air. Aviation turbine fuel is injected through an air-blast atomizer. An unsteady pressure transducer is located at the primary zone to measure the acoustic oscillations. The frequency of sound generated during the combustion process is compared with a microphone located at 1.25 m away from the combustor at an angle of 45° from the axis of the combustor.
The main objective of this paper is to investigate the cause of hooting and the passive control techniques in order to reduce it. This is achieved by two ways, systematically by two ways, i) reducing the quenching air methodologically reducing the quenching air and ii) varying the air to liquid (fuel) ratio (ALR). By imparting these methods the sound pressure level inside the combustor is reduced from 143dB to 128dB. Since, combustion noise occurs in a broad-band of frequencies, the unsteady data obtained with the pressure transducer are analyzed using octave bands, where it shows linear decrement of energy present in-between the two frequencies. In order to perform parametric study, two swirlers of swirl numbers.0.77 and 0.86 are used. Established by the physics of Helmholtz oscillator, the combustor hooting is dictated, by which the sound produced by the combustor is explained.
Model Order Reduction of Visco-Thermal Acousto-Elastic Interaction in High-Pressure Centrifugal Compressors
Authors: Jith Jithin , Sarkar Sunetra 
Published: February 2016

Centrifugal compressors used in applications like enhanced oil recovery using gas re-injection and Carbon capture and sequestration operate at very high pressures and often have to to deal with supercritical CO2 which is considerably viscous. Increased viscosity leads to energy dissipation and introduces damping in the acousto-elastic interaction between supercritical CO2 and the impeller of a centrifugal compressor, thereby altering the frequency response of the system especially near resonant frequencies. In this paper, the damping introduced by visco-thermal effects in such acousto-elastic systems is accounted for in a numerically efficient manner.
The acoustics in the fluid are modelled using the Boundary Layer Impedance (BLI) model and the centrifugal impeller as a linear elastic structure. The coupled acousto-elastic system is then solved using the finite element method. The finite element solution becomes computationally expensive especially when working with large three-dimensional models. In order to reduce the computational cost, a model order reduction technique based on a multi-point second-order Arnoldi (SOAR) procedure is developed. It is demonstrated that the reduced order model significantly brings down the computational time while being sufficiently accurate.
Instabilities Investigation in Wet Gas Compressor by Flow Visualisation
Authors: Ferrara Veronica , Bakken Lars E. 
Published: February 2016

Since the production of oil and gas is declining, the development and implementation of new, cost-efficient technology is an important focus area in order to enhance production and recovery from existing fields. The wet gas compressor represents a key element because it has been identified as one of the most relevant technologies to be developed.
In recent years, research on subsea installations has been carried out. A traditional centrifugal compressor may not be applicable to handle liquid during a standard process. A complete comprehension of the machine behaviour, in particular investigation with the presence of gas-liquid mixture is essential. Because of liquid impact, compressor performances and consequently the margin of stability might be modified. Delayed instability inception should also be pointed out.
The objective of this paper is to provide a consistent basis for the surge and rotating stall analysis of wet gas compressors and describe the mechanism leading to instabilities and their evolution. Visualisation of flow in the compressor stage is accomplished by means of fluorescent injection in correspondence with the impeller labyrinth seal and diffuser section. Simultaneously, a fast Fourier transform examination is realised in order to identify characteristic frequencies of unsteady events.
Toll-Like Receptor Activation by Generalized Modules for Membrane Antigens from Lipid A Mutants of Salmonella enterica Serovars Typhimurium and Enteritidis
Authors: Rossi Omar , Caboni Mariaelena , Negrea Aurel , Necchi Francesca , Alfini Renzo , Micoli Francesca , Saul Allan , MacLennan Calman A. , Rondini Simona , Gerke Christiane 
Published: February 2016

ABSTRACT

Invasive nontyphoidal
Salmonella
(iNTS) disease is a neglected disease with high mortality in children and HIV-positive individuals in sub-Saharan Africa, caused primarily by Africa-specific strains of
Salmonella enterica
serovars Typhimurium and Enteritidis. A vaccine using GMMA (generalized modules for membrane antigens) from
S.
Typhimurium and
S.
Enteritidis containing lipid A modifications to reduce potential
in vivo
reactogenicity is under development. GMMA with penta-acylated lipid A showed the greatest reduction in the level of cytokine release from human peripheral blood monocytes from that for GMMA with wild-type lipid A. Deletion of the lipid A modification genes
msbB
and
pagP
was required to achieve pure penta-acylation. Interestingly, Δ
msbB
Δ
pagP
GMMA from
S.
Enteritidis had a slightly higher stimulatory potential than those from
S.
Typhimurium, a finding consistent with the higher lipopolysaccharide (LPS) content and Toll-like receptor 2 (TLR2) stimulatory potential of the former. Also, TLR5 ligand flagellin was found in
Salmonella
GMMA. No relevant contribution to the stimulatory potential of GMMA was detected even when the flagellin protein FliC from
S.
Typhimurium was added at a concentration as high as 10% of total protein, suggesting that flagellin impurities are not a major factor for GMMA-mediated immune stimulation. Overall, the stimulatory potential of
S.
Typhimurium and
S.
Enteritidis Δ
msbB
Δ
pagP
GMMA was close to that of
Shigella
sonnei
GMMA, which are currently in phase I clinical trials.
Hepatitis C Virus-Induced Degradation of Cell Death-Inducing DFFA-Like Effector B Leads to Hepatic Lipid Dysregulation
Authors: Lee Emily M. , Alsagheir Ali , Wu Xianfang , Hammack Christy , McLauchlan John , Watanabe Noriyuki , Wakita Takaji , Kneteman Norman M. , Douglas Donna N. , Tang Hengli 
Published: February 2016

ABSTRACT
Individuals chronically infected with hepatitis C virus (HCV) commonly exhibit hepatic intracellular lipid accumulation, termed steatosis. HCV infection perturbs host lipid metabolism through both cellular and virus-induced mechanisms, with the viral core protein playing an important role in steatosis development. We have recently identified a liver protein, the cell death-inducing DFFA-like effector B (CIDEB), as an HCV entry host dependence factor that is downregulated by HCV infection in a cell culture model. In this study, we investigated the biological significance and molecular mechanism of this downregulation. HCV infection in a mouse model downregulated CIDEB in the liver tissue, and knockout of the CIDEB gene in a hepatoma cell line results in multiple aspects of lipid dysregulation that can contribute to hepatic steatosis, including reduced triglyceride secretion, lower lipidation of very-low-density lipoproteins, and increased lipid droplet (LD) stability. The potential link between CIDEB downregulation and steatosis is further supported by the requirement of the HCV core and its LD localization for CIDEB downregulation, which utilize a proteolytic cleavage event that is independent of the cellular proteasomal degradation of CIDEB.

IMPORTANCE
Our data demonstrate that HCV infection of human hepatocytes
in vitro
and
in vivo
results in CIDEB downregulation via a proteolytic cleavage event. Reduction of CIDEB protein levels by HCV or gene editing, in turn, leads to multiple aspects of lipid dysregulation, including LD stabilization. Consequently, CIDEB downregulation may contribute to HCV-induced hepatic steatosis.
Does Lean healthcare improve patient satisfaction? A mixed-method investigation into primary care
Authors: Poksinska Bozena Bonnie , Fialkowska-Filipek Malgorzata , Engström Jon 
Published: February 2016

BackgroundLean healthcare is claimed to contribute to improved patient satisfaction, but there is limited evidence to support this notion. This study investigates how primary-care centres working with Lean define and improve value from the patient's perspective, and how the application of Lean healthcare influences patient satisfaction.MethodsThis paper contains two qualitative case studies and a quantitative study based on results from the Swedish National Patient Survey. Through the case studies, we investigated how primary-care organisations realised the principle of defining and improving value from the patient's perspective. In the quantitative study, we compared results from the patient satisfaction survey for 23 primary-care centres working with Lean with a control group of 23 care centres not working with Lean. We also analysed changes in patient satisfaction over time.ResultsOur case studies reveal that Lean healthcare implementations primarily target efficiency and little attention is paid to the patient's perspective. The quantitative study shows no significantly better results in patient satisfaction for primary-care centres working with Lean healthcare compared with those not working with Lean. Further, care centres working with Lean show no significant improvements in patient satisfaction over time.ConclusionsLean healthcare implementations seem to have a limited impact on improving patient satisfaction. Care providers need to pay more attention to integrating the patient's perspective in the application of Lean healthcare. Value needs to be defined and value streams need to be improved based on both the knowledge and clinical expertise of care providers, and the preferences and needs of patients.
Implantation of healthy matrix-embedded endothelial cells rescues dysfunctional endothelium and ischaemic tissue in liver engraftment
Authors: Melgar-Lesmes Pedro , Balcells Mercedes , Edelman Elazer R 
Published: February 2016

ObjectiveLiver transplantation is limited by ischaemic injury which promotes endothelial cell and hepatocyte dysfunction and eventually organ failure. We sought to understand how endothelial state determines liver recovery after hepatectomy and engraftment.DesignMatrix-embedded endothelial cells (MEECs) with retained healthy phenotype or control acellular matrices were implanted in direct contact with the remaining median lobe of donor mice undergoing partial hepatectomy (70%), or in the interface between the remaining median lobe and an autograft or isograft from the left lobe in hepatectomised recipient mice. Hepatic vascular architecture, DNA fragmentation and apoptosis in the median lobe and grafts, serum markers of liver damage and phenotype of macrophage and lymphocyte subsets in the liver after engraftment were analysed 7 days post-op.ResultsHealthy MEECs create a functional vascular splice in donor and recipient liver after 70% hepatectomy in mouse protecting these livers from ischaemic injury, hepatic congestion and inflammation. Macrophages recruited adjacent to the vascular nodes into the implants switched to an anti-inflammatory and regenerative profile M2. MEECs improved liver function and the rate of liver regeneration and prevented apoptosis in donor liver lobes, autologous grafts and syngeneic engraftment.ConclusionsImplants with healthy endothelial cells rescue liver donor and recipient endothelium and parenchyma from ischaemic injury after major hepatectomy and engraftment. This study highlights endothelial-hepatocyte crosstalk in hepatic repair and provides a promising new approach to improve regenerative medicine outcomes and liver transplantation.
Immunisation coverage in rural–urban migrant children in low and middle-income countries (LMICs): a systematic review and meta-analysis
Authors: Awoh Abiyemi Benita , Plugge Emma 
Published: February 2016

BackgroundThe majority of children who die from vaccine-preventable diseases (VPDs) live in low-income and-middle-income countries (LMICs). With the rapid urbanisation and rural–urban migration ongoing in LMICs, available research suggests that migration status might be a determinant of immunisation coverage in LMICs, with rural–urban migrant (RUM) children being less likely to be immunised.ObjectivesTo examine and synthesise the data on immunisation coverage in RUM children in LMICs and to compare coverage in these children with non-migrant children.MethodsA multiple database search of published and unpublished literature on immunisation coverage for the routine Expanded Programme on Immunisation (EPI) vaccines in RUM children aged 5 years and below was conducted. Following a staged exclusion process, studies that met the inclusion criteria were assessed for quality and data extracted for meta-analysis.ResultsEleven studies from three countries (China, India and Nigeria) were included in the review. There was substantial statistical heterogeneity between the studies, thus no summary estimate was reported for the meta-analysis. Data synthesis from the studies showed that the proportion of fully immunised RUM children was lower than the WHO bench-mark of 90% at the national level. RUMs were also less likely to be fully immunised than the urban-non-migrants and general population. For the individual EPI vaccines, all but two studies showed lower immunisation coverage in RUMs compared with the general population using national coverage estimates.ConclusionsThis review indicates that there is an association between rural–urban migration and immunisation coverage in LMICs with RUMs being less likely to be fully immunised than the urban non-migrants and the general population. Specific efforts to improve immunisation coverage in this subpopulation of urban residents will not only reduce morbidity and mortality from VPDs in migrants but will also reduce health inequity and the risk of infectious disease outbreaks in wider society.
Ebola, jobs and economic activity in Liberia
Authors: Bowles Jeremy , Hjort Jonas , Melvin Timothy , Werker Eric 
Published: February 2016

BackgroundThe 2014 Ebola virus disease (EVD) outbreak in the neighbouring West African countries of Guinea, Liberia and Sierra Leone represents the most significant setback to the region's development in over a decade. This study provides evidence on the extent to which economic activity declined and jobs disappeared in Liberia during the outbreak.MethodsTo estimate how the level of activity and number of jobs in a given set of firms changed during the outbreak, we use a unique panel data set of registered firms surveyed by the business-development non-profit organisation, Building Markets. We also compare the change in economic activity during the outbreak, across regions of the country that had more versus fewer Ebola cases in a difference-in-differences approach.FindingsWe find a large decrease in economic activity and jobs in all of Liberia during the Ebola outbreak, and an especially large decline in Monrovia. Outside of Monrovia, the restaurants, and food and beverages sectors have suffered the most among the surveyed sectors, and in Monrovia, the construction and restaurant sectors have shed the most employees, while the food and beverages sectors experienced the largest drop in new contracts. We find little association between the incidence of Ebola cases and declines in economic activity outside of Monrovia.ConclusionsIf the large decline in economic activity that occurred during the Ebola outbreak persists, a focus on economic recovery may need to be added to the efforts to rebuild and support the healthcare system in order for Liberia to regain its footing.
The impact of childhood residential mobility on mental health outcomes in adolescence and early adulthood: a record linkage study
Authors: Tseliou Foteini , Maguire Aideen , Donnelly Michael , O'Reilly Dermot 
Published: February 2016

BackgroundUnderstanding the causes of poor mental health in early childhood and adolescence is important as this can be a significant determinant of mental well-being in later years. One potential and relatively unexplored factor is residential mobility in formative years. Previous studies have been relatively small and potentially limited due to methodological issues. The main aim of this study was to investigate the relationship between early residential instability and poor mental health among adolescents and young adults in Northern Ireland.MethodsA Census-based record linkage study of 28% of children aged 0–8 years in 2001 in Northern Ireland (n=49 762) was conducted, with six monthly address change assessments from health registration data and self-reported mental health status from the 2011 Census. Logistic regression models were built adjusting for socioeconomic status (SES), household composition and marital dissolution.ResultsThere was a graded relationship between the number of address changes and mental ill-health (adjusted OR 3.67, 95% CIs 2.11 to 6.39 for 5 or more moves). This relationship was not modified by SES or household composition. Marital dissolution was associated with poor mental health but did not modify the relationship between address change and mental health (p=0.206). There was some indication that movement after the age of five was associated with an increased likelihood of poor mental health.ConclusionsThis large study clearly confirms the close relationship between address change in early years and later poor mental health. Residential mobility may be a useful marker for children at risk of poorer mental health in adolescence and early adulthood.
Association between personality traits and future choice of specialisation among Swedish doctors: a cross-sectional study
Authors: Bexelius Tomas S , Olsson Caroline , Järnbert-Pettersson Hans , Parmskog Malin , Ponzer Sari , Dahlin Marie 
Published: February 2016

AbstractBackgroundMedical students' choice of their future specialty is influenced by several factors, including working conditions and type of patient relations. The aim of this study was to investigate the association between the choice of specialty and personality traits.MethodsThis is a cross-sectional questionnaire-based study of 399 alumni from Karolinska Institutet Medical School who were assumed to undergo specialty training at the time of the survey in 2013. The Big Five Inventory was used to assess the personality traits extraversion, agreeableness, conscientiousness, neuroticism and openness to experience. Medical specialties were categorised as primary care, psychiatry, internal medicine and surgical and hospital service specialties. Adjustments were made for demographic factors and the method of selection for medical school admission.ResultsThe response rate was 72% (n=289, of which 262 were in training to become specialists). Among these, surgeons scored lower in agreeableness than physicians in primary care, internal medicine and hospital services. Psychiatrists and hospital service physicians showed lower conscientiousness compared with surgeons.ConclusionsWe found distinctive differences in personality traits between medical specialties even after adjusting for other potential explanatory variables. Since there are differences between specialties, for example, surgeons and psychiatrists, this supports previous findings that personality may affect medical students' specialty choice also in a Swedish setting.