bluuebunny/crossref_metadata_2025 huggingface dataset:
Different symptoms in carrots caused by male and female carrot psyllid feeding and infection by ‘Candidatus Liberibacter solanacearum’
Authors: Nissinen A. I. , Haapalainen M. , Jauhiainen L. , Lindman M. , Pirhonen M.
Published: October 2013

Carrot psyllid Trioza apicalis was recently found to carry the plant pathogenic bacterium ‘Candidatus Liberibacter solanacearum’ (CLs). To confirm the transmission of bacteria by the psyllids and to dissect the symptoms caused in carrot plants by psyllid feeding and CLs infection, a greenhouse experiment with single psyllids feeding on separate plants was performed. A positive correlation was found between the amount of CLs bacteria in the psyllids and in the corresponding plants exposed to feeding, indicating CLs transmission. The female psyllid feeding caused more severe damage than male feeding, and resulted in a substantial decrease in the root weight. Female psyllid feeding also significantly reduced the carrot leaf weight and increased the number of curled leaves. The number of curled leaves was also increased by the nymphs when their number exceeded 10 per plant. A high titre of CLs bacteria significantly reduced root weight, while not affecting the weight or number of the leaves. However, the amount of CLs correlated with the number of leaves showing discolouration symptoms. Microscopy of infected carrot plants revealed that the phloem tubes throughout the whole plant, from leaf veins to the root tip, were colonized by bacteria. The bacterial cells appeared to be long and thin flexible rods with tapering ends and a transversally undulated surface. Microscopy also revealed collapsed phloem cells in the infected carrots. Damage in the phloem vessels is likely to reduce the sucrose transport from source leaves to the root, explaining the observed leaf discolouration and reduction in root weight.
Probabilistic Strategies for Familial DNA Searching
Authors: Slooten Klaas , Meester Ronald
Published: October 2013

Familial searching is the process of searching in a deoxyribonucleic acid (DNA) database for relatives of a certain individual. Typically, this individual is the source of a crime stain that can be reasonably attributed to the offender. If this crime stain has not given rise to a match in a DNA database, then in some jurisdictions a familial search may be carried out to attempt to identify a relative of the offender, thus giving investigators a lead. We discuss two methods to select a subset from the database that contains a relative (if present) with a probability that we can control. The first method is based on a derivation of the likelihood ratio for each database member in favour of being the relative, taking all DNA profiles in the database into account. This method needs prior probabilities and yields posterior probabilities. The second method is based on case-specific false positive and false negative rates. We discuss the relationship between the approaches and assess the methods with familial searching carried out in the Dutch national DNA database. We also give practical recommendations on the usefulness of both methods.
The narrative structure as a way to gain insight into peoples' experiences: one methodological approach
Authors: Rejnö Åsa , Berg Linda , Danielson Ella
Published: October 2013

The narrative method is used in healthcare research, mostly in data collection but also in the analysis. Narrative approaches draw attention to how people tell about and create meaning of experiences. The aim of the article was to examine the narrative structure, the elements in the structure and their function and how these can be used in research to gain insights into experiences. Examples are taken from a material of narratives from a study where next of kin were asked to narrate their experiences of sudden and unexpected death from stroke. The narratives had a clear beginning, midpoint and ending. In the beginning, orientation of the narrated events was given. The narrated events were told to have a turning point constituted of complicating actions that lead to a resolution that solved the narrated event. The narratives were built up by multiple recaps into the narrated events and also consisted of asides – side narratives and flashbacks – events back in time. Use of a narrative structure can contribute with valuable information that might be missed with other analysis. The analysis can be used on its own, as a complement to other narrative analysis or even as a complement to other qualitative analysis.
Storm‐dominated shelf‐edge delta successions in a high accommodation setting: The palaeo‐Orinoco Delta (Mayaro Formation), Columbus Basin, South‐East Trinidad
Authors: Bowman Andrew P. , Johnson Howard D.
Published: October 2013

Pliocene age deposits of the palaeo‐Orinoco Delta are evaluated in the Mayaro Formation, which crops out along the western margin of the Columbus Basin in south‐east Trinidad. This sandstone‐dominated interval records the diachronous, basinwards migration of the shelf edge of the palaeo‐Orinoco Delta, as it prograded eastwards during the Pliocene–Pleistocene (ca 3·5 Ma). The basin setting was characterized by exceptionally high rates of growth‐fault controlled sediment supply and accommodation space creation resulting in a gross basin‐fill of around 12 km, with some of the highest subsidence rates in the world (ca 5 to 10 m ka−1). This analysis demonstrates that the Mayaro Formation was deposited within large and mainly wave‐influenced shelf‐edge deltas. These are manifested as multiple stacks of coarsening upward parasequences at scales ranging from tens to hundreds of metres in thickness, which are dominated by storm‐influenced and wave‐influenced proximal delta‐front sandstones with extensive, amalgamated swaley and hummocky cross‐stratification. These proximal delta‐front successions pass gradationally downwards into 10s to 100 m thick distal delta front to mud‐dominated upper slope deposits characterized by a wide variety of sedimentary processes, including distal river flood and storm‐related currents, slumps and other gravity flows. Isolated and subordinate sandstone bodies occur as gully fills, while extensive soft sediment deformation attests to the high sedimentation rates along a slope within a tectonically active basin. The vertical stratigraphic organization of the facies associations, together with the often cryptic nature of parasequence stacking patterns and sequence stratigraphic surfaces, are the combined product of the rapid rates of accommodation space creation, high rates of sediment supply and glacio‐eustasy in the 40 to 100 Ka Milankovitch frequency range. The stratigraphic framework described herein contrasts strikingly with that described from passive continental margins, but compares favourably to other tectonically active, deltaic settings (for example, the Baram Delta Province of north‐west Borneo).
Differing Domains of Actual Sibling Conflict Discussions and Associations with Conflict Styles and Relationship Quality
Authors: Campione‐Barr Nicole , Bassett Greer Kelly , Schwab Kayla , Kruse Anna
Published: October 2013

Four types of sibling conflict were identified in actual adolescent sibling discussions: equality and fairness, invasion of the personal domain, intrinsic harm, and relationships. Older [M = 14.97, standard deviation (SD) = 1.69 years] and younger siblings (M = 12.20, SD = 1.90 years) from 144 dyads discussed conflicts during a semi‐structured conflict task. Trained observers coded the topics discussed, and separate observers rated their conflict styles, whereas siblings rated their relationship quality. The proportion of conflicts of each domain differed by dyadic gender composition. Equality and fairness conflicts (and invasion of the personal domain conflicts for sister–sister pairs) were discussed the most frequently whereas intrinsic harm conflicts were associated with destructive conflict styles. Siblings' discussions of conflicts involving intrinsic harm were associated with older siblings' reports of negative relationship quality. The associations between these conflict topics and negative relationship quality were mediated by the siblings discussing the conflicts in destructive ways.
Patient care pathways under the model of integrating tuberculosis service with general hospitals in China
Authors: Wei Xiaolin , Yin Jia , Zou Guanyang , Walley John , Zhong Jiemign , Chen Songhua , Sun Qiang , Wang Xiaoming
Published: October 2013

Objective

To report care pathways of tuberculosis (TB) patients under the integrated model, where TB clinical service is provided by a general hospital instead of the TB dispensary, with the aim of providing policy recommendations for TB care reforms in China.

Methods

Six counties implementing the integrated model were randomly selected, and 50 TB patients in each county participated in a questionnaire survey.

Results

Of the 301 participants, 82 visited only the TB designated hospital. A patient visited a median of two health providers in total. The median external provider delay and internal provider delay were 1 and 0 day, respectively. The median out‐of‐pocket medical costs were US$379 in total; US$293 in the TB units and US$0 in other health units in the TB designated hospital. Logistic regression analyses suggested that patients who visited the primary care facilities first tended to have longer external delays (OR = 5.71) than patients who visited the other hospitals (OR = 10.16).

Conclusion

The integrated model is promising as it reported relatively fewer patient pathways and shorter delays than the dispensary model. However, the integrated model did not reduce patient out‐of‐pocket costs.
Diabetes mellitus and tuberculosis: pattern of tuberculosis, two‐month smear conversion and treatment outcomes in Guangzhou, China
Authors: Mi Fengling , Tan Shouyong , Liang Li , Harries Anthony D. , Hinderaker Sven G. , Lin Yan , Yue Wentao , Chen Xi , Liang Bing , Gong Fang , Du Jian
Published: October 2013

Objective

There is a high burden of both diabetes (DM) and tuberculosis (TB) in China. We evaluated the association between DM and the pattern of disease, 2‐month sputum smear conversion and treatment outcomes of patients with TB in Guangzhou, China.

Method

All patients registered with TB from September 2011 to June 2012 were screened for DM and assessed for treatment outcomes in relation to presence or absence of DM and quality of DM control using patient registers, treatment cards and electronic record systems.

Results

There were 1589 patients with TB of whom 189 (12%) had DM. Among those with DM, there was a significantly higher proportion of men, persons aged 35 years and older and persons with smear‐positive pulmonary tuberculosis (PTB) (P < 0.01). In patients with DM and new smear‐positive PTB, there was a higher proportion who had positive sputum smears at 2 months (21.7% vs. 5.6%, RR 3.85, 95%CI 2.24–6.63), who were lost‐to‐follow‐up (5.2% vs. 1.7%, RR 3.23, 95%CI 1.08–9.63) and who failed treatment (10.3% vs. 2.3%, RR 4.46, 95%CI 1.96–10.18) compared with patients who had no DM. There was no significant association between these adverse outcomes and DM control as measured by 2 and 6‐month fasting blood glucose.

Conclusion

Diabetes mellitus in new smear‐positive patients with PTB was associated with failure to sputum smear convert at 2 months and adverse treatment outcomes of loss‐to‐follow‐up and failure. Further research is needed to understand the reasons for these findings and to determine whether the current length of treatment of 6 months is adequate.
Evaluation of hair loss in cats occurring after treatment with a topical flea control product
Authors: Credille Kelly M. , Thompson Lori A. , Young Lisa M. , Meyer Jeffery A. , Winkle Joseph R.
Published: October 2013

Background

A formulation containing 39.6% spinetoram resulted in a higher than anticipated number of reports of alopecia at the site of application in the first months following commercial product launch.

Hypothesis/Objectives

To determine the cause of the alopecia using histopathology, including assessment for inflammation, follicular findings of physical trauma (plucking/pulling behaviour) and changes in follicular cycling.

Animals

Twenty‐four flea‐free, male and female adult domestic short hair cats within a private research colony.

Methods

Cats were treated with a single application of 39.6% spinetoram on day 0; personnel were not blinded. Observations of the skin and hair coat began immediately and were repeated at 30 min and 1, 2, 3, 4, 6, 8 and 12 h post‐application and then on subsequent days at the same time as initial dosing and at 2, 4, 6, 8 and 12 h after that time, until day 5. If hair thinning or loss was observed, a skin biopsy sample was collected. Two cats not exhibiting abnormalities were biopsied on day 6.

Results

Thirty‐eight per cent of cats (nine of 24) developed hair thinning and alopecia of sufficient severity within 78 h post‐application of the product to warrant skin biopsy. Abnormalities in the skin were limited to the application site and were consistent with physical trauma (pulling or plucking) to the hair.

Conclusions and clinical importance

Microscopic changes in the hair follicles of affected cats were consistent with self‐induced trauma or barbering behaviour. All changes were reversible and paralleled findings associated with well‐established, topical flea control products.
Effect of Partial Welding on the Residual Stress and Structural Integrity of Piping Welds
Authors: Katsuyama Jinya , Masaki Koichi , Onizawa Kunio
Published: October 2013

When weld defects are observed during an inspection after welding, repair welding is performed after removing the defects. However, partial repair welding can potentially complicate the weld residual stress distribution. In this study, we performed thermal-elastic-plastic analyses to evaluate the weld residual stress produced by repair welding after pipe butt-welding. The analysis results were validated through comparison with actual measurements. In addition, based on the analysis results for varying repair-welding conditions, we also performed structural integrity assessments related to stress corrosion cracking using the probabilistic fracture mechanics analysis code pascal-sp. It was clearly observed that the tensile stress in the repair-welded region increased and that compressive stresses occurred outside the repair-welded region. A deeper mechanical cutting depth caused larger increases in the tensile residual stress of the repair-welded region. It was also concluded that partial repair welding may favorably affect the break probability of piping welds.
Design and Performance Optimization of Large Stroke Spatial Flexures
Authors: Wiersma D. H. , Boer S. E. , Aarts R. G. K. M. , Brouwer D. M.
Published: October 2013

Flexure hinges inherently lose stiffness in supporting directions when deflected. In this paper a method is presented for optimizing the geometry of flexure hinges, which aims at maximizing supporting stiffnesses. In addition, the new ∞-flexure hinge design is presented. The considered hinges are subjected to a load and deflected an angle of up to ±20 deg. The measure of performance is defined by the first unwanted natural frequency, which is closely related to the supporting stiffnesses. During the optimization, constraints are applied to the actuation moment and the maximum occurring stress. Evaluations of a curved hinge flexure, cross revolute hinge, butterfly flexure hinge, two cross flexure hinge types, and the new ∞-flexure hinge are presented. Each of these hinge types is described by a parameterized geometric model. A flexible multibody modeling approach is used for efficient modeling while it accounts for the nonlinear geometric behavior of the stiffnesses. The numerical efficiency of this model is very beneficial for the design optimization. The obtained optimal hinge designs are validated with a finite element model and show good agreement. The optimizations show that a significant increase in supporting stiffness, with respect to the conventional cross flexure hinge, can be achieved with the ∞-flexure hinge.
Biaxial Normal Strength Behavior in the Axial-Transverse Plane for Human Trabecular Bone—Effects of Bone Volume Fraction, Microarchitecture, and Anisotropy
Authors: Sanyal Arnav , Keaveny Tony M.
Published: October 2013

The biaxial failure behavior of the human trabecular bone, which has potential relevance both for fall and gait loading conditions, is not well understood, particularly for low-density bone, which can display considerable mechanical anisotropy. Addressing this issue, we investigated the biaxial normal strength behavior and the underlying failure mechanisms for human trabecular bone displaying a wide range of bone volume fraction (0.06–0.34) and elastic anisotropy. Micro-computed tomography (CT)-based nonlinear finite element analysis was used to simulate biaxial failure in 15 specimens (5 mm cubes), spanning the complete biaxial normal stress failure space in the axial-transverse plane. The specimens, treated as approximately transversely isotropic, were loaded in the principal material orientation. We found that the biaxial stress yield surface was well characterized by the superposition of two ellipses—one each for yield failure in the longitudinal and transverse loading directions—and the size, shape, and orientation of which depended on bone volume fraction and elastic anisotropy. However, when normalized by the uniaxial tensile and compressive strengths in the longitudinal and transverse directions, all of which depended on bone volume fraction, microarchitecture, and mechanical anisotropy, the resulting normalized biaxial strength behavior was well described by a single pair of (longitudinal and transverse) ellipses, with little interspecimen variation. Taken together, these results indicate that the role of bone volume fraction, microarchitecture, and mechanical anisotropy is mostly accounted for in determining the uniaxial strength behavior and the effect of these parameters on the axial-transverse biaxial normal strength behavior per se is minor.
Effect of Gravity Modulation on Electrothermal Convection in a Dielectric Fluid Saturated Anisotropic Porous Layer
Authors: Swamy Mahantesh S. , Shivakumara I. S. , Naduvinamani N. B.
Published: October 2013

This paper deals with linear and nonlinear stability analyses of thermal convection in a dielectric fluid saturated anisotropic Brinkman porous layer subject to the combined effect of AC electric field and time-periodic gravity modulation (GM). In the realm of linear theory, the critical stability parameters are computed by regular perturbation method. The local nonlinear theory based on truncated Fourier series method gives the information of convection amplitudes and heat transfer. Principle of exchange of stabilities is found to be valid and subcritical instability is ruled out. Based on the governing linear autonomous system several qualitative results on stability are discussed. The sensitive dependence of the solution of Lorenz system of electrothermal convection to the choice of initial conditions points to the possibility of chaos. Low frequency g-jitter is found to have significant stabilizing influence which is in turn diminished by an imposed AC electric field. The role of other governing parameters on the stability threshold and on transient heat transfer is determined.
Aeromechanical Optimization of a Winglet-Squealer Tip for an Axial Turbine
Authors: Schabowski Zbigniew , Hodson Howard , Giacche Davide , Power Bronwyn , Stokes Mark R.
Published: October 2013

The possibility of reducing the over tip leakage loss of unshrouded axial turbine rotors has been investigated in an experiment using a linear cascade of turbine blades and by using CFD. A numerical optimization of a winglet-squealer geometry was performed. The optimization involved the structural analysis alongside the CFD. Significant effects of the tip design on the tip gap flow pattern, loss generation and mechanical deformation under centrifugal loads were found. The results of the optimization process were verified by low speed cascade testing. The measurements showed that the optimized winglet-squealer design had a lower loss than the flat tip at all of the tested tip gaps. At the same time, it offered a 37% reduction in the rate of change of the aerodynamic loss with the tip gap size. The optimized tip geometry was used to experimentally assess the effects of the opening of the tip cavity in the leading edge part of the blade and the inclination of the pressure side squealer from the radial direction. The opening of the cavity had a negligible effect on the aerodynamic performance of the cascade. The squealer lean resulted in a small reduction of the aerodynamic loss at all the tested tip gaps. It was shown that a careful consideration of the mechanical aspects of the winglet is required during the design process. Mechanically unconstrained designs could result in unacceptable deformation of the winglet due to centrifugal loads. An example winglet geometry is presented that produced a similar aerodynamic loss to that of the optimized tip but had a much worse mechanical performance. The mechanisms leading to the reduction of the tip leakage loss were identified. Using this knowledge, a simple method for designing the tip geometry of a shroudless turbine rotor is proposed. Numerical calculations indicated that the optimized low-speed winglet-squealer geometry maintained its aerodynamic superiority over the flat tip blade with the exit Mach number increased from 0.1 to 0.8.
Convex Curvature Effects on Film Cooling Adiabatic Effectiveness
Authors: Winka James R. , Anderson Joshua B. , Boyd Emily J. , Bogard David G. , Crawford Michael E.
Published: October 2013

Surface curvature is known to have significant effects on film cooling performance, with convex curvature inducing increased film effectiveness and concave curvature causing decreased film effectiveness. Generally, these curvature effects have been presumed to scale with 2r/d at the film cooling hole location, where r is the radius of curvature and d is coolant hole diameter. In this study, the validity of this scaling of curvature effects are examined by performing experiments in regions of large and low curvature on a model vane. Single rows of cylindrical holes were placed at various locations along the high curvature section of the suction side of the vane. For the first series of experiments, a single row of holes was placed at two locations with different local surface curvature. The coolant hole diameters were then adjusted to match 2r/d values. Results from these experiments showed that there was better correspondence of film performance when using the 2r/d scaling, but there was not an exact matching of performance. A second series of experiments focused on evaluating the effects of curvature downstream of the coolant holes. One row of holes was placed at a position upstream of the highest curvature, while another row was placed at a downstream position such that the radius of curvature was equivalent for the two rows of holes. Results indicated that the local radius of curvature is not sufficient in understanding the performance of film cooling. Instead, the curvature envelope downstream of the coolant holes plays a significant role on the performance of film cooling for cylindrical holes.
Understanding the Flow Behavior in a Low Hub-Tip Ratio, High Aspect Ratio Contra-Rotating Axial Fan Stage
Authors: Mistry Chetan S. , Pradeep A. M.
Published: October 2013

This paper discusses the results of a parametric study of a pair of contra-rotating axial fan rotors. The rotors were designed to deliver a mass flow of 6 kg/s at 2400 rpm. The blades were designed with a low hub-tip ratio of 0.35 and an aspect ratio of 3.0. Numerical and experimental studies were carried out on these contra-rotating rotors operating at a Reynolds number of 1.25 × 105 (based on blade chord). The axial spacing between the rotors was varied between 50 to 120 % of the chord of rotor 1. The performance of the rotors was evaluated at each of these spacing at design and off-design speeds. The results from the numerical study (using ANSYS CFX) were validated using experimental data. In spite of certain limitations of CFD under certain operating conditions, it was observed that the results agreed well with those from the experiments.

The performance of the fan was evaluated based on the variations of total pressure, velocity components and flow angles at design and off-design operating conditions. The measurement of total pressure, flow angles etc. are taken upstream of the first rotor, between the two rotors and downstream of the second rotor. It was observed that the aerodynamics of the flow through a contra rotating stage is significantly influenced by the axial spacing between the rotors and the speed ratio of the rotors. With increasing speed ratios, the strong suction generated by the second rotor, improves the stage pressure rise and the stall margin. Lower axial spacing on the other hand, changes the flow incidence to the second rotor and thereby improves the overall performance of the stage. The performance is investigated at different speed ratios of the rotors at varying axial spacing.
Annular Supersonic Ejector Design and Optimization
Authors: Sathiyamoorthy K. , Iyengar Venkat S. , Manjunath P.
Published: October 2013

An ejector is a device that entrains a secondary flow into a high speed stream that is generated by expansion of high pressure motive gas [1]. These ejectors can be broadly classified into central ejectors and annular ejectors. A large majority of applications involve central ejectors where the motive gas flow is injected along the centre of the flow passage of the secondary flow. Dutton and Carroll [2] proposed an optimization procedure for such ejectors without taking the mixed supersonic flow region into account and generated the design curves considering the constant Total temperature, Molecular weight and Specific heat ratios. However in some applications involving high temperature gases such as in ramjet/scramjet and gas turbine test facilities, an annular supersonic ejector is more appropriate where annular injection of the motive gas at the periphery of the flow passage is desired to avoid the exposure of the motive gas flow nozzle to the high temperature combustion product gases. A design and optimization procedure for an annular supersonic ejector based on the earlier approach [2] with the mixed supersonic flow region and incorporating variable Total temperature, Molecular weight and Specific heat ratios in the model has been developed based on simplified one dimensional constant area mixing model and verified using CFD software Fluent.
Experimental Evaluation of Cooling Effectiveness of High Pressure Turbine Nozzle Guide Vane
Authors: Venkatasubramanya S. , Vasudev S. A. , Chandel Sunil
Published: October 2013

High pressure turbine nozzle guide vane of a gas turbine engine, which operates at gas temperatures in excess of 1700 K, employs internal cooling, augmented convective cooling, impingement cooling and film cooling techniques to keep the vane in safe operating limits. Even though nozzle guide vanes are designed using heat transfer co-relations available in published papers and fundamental data, it is required to test the nozzle guide vane to ascertain the surface metal temperature and verify the adequacy of cooling. Adequacy of cooling is quantified by the term cooling effectiveness expressed and as percentage. The objective of the current work is to study the effect of gas to cooling air temperature ratio on cooling effectiveness. In the current study tests were first conducted to validate the test cascade in accordance with AGARD recommendations. Later tests were conducted to verify the constancy of cooling effectiveness across two gas temperatures and finally effect of gas to cooling air temperature ratio on cooling effectiveness was studied. The ratio was increased by a factor of 0.69 in leading edge and 0.72 in the trailing edge circuit and found that the cooling effectiveness remained constant.
Second Law Efficiency of an Intercooled-Reheated-Regenerative-Brayton Cycle With Variable Temperature Heat Reservoirs
Authors: Anand Vishal , Nelanti Krishna , Gujar Kamlesh G.
Published: October 2013

The gas turbine engine works on the principle of the Brayton Cycle. One of the ways to improve the efficiency of the gas turbine is to make changes in the Brayton Cycle. In the present study, Brayton Cycle with intercooling, reheating and regeneration with variable temperature heat reservoirs is considered. Instead of the usual thermodynamic efficiency, the Second law efficiency, defined on the basis of lost work, has been taken as a parameter to study the deviation of the irreversible Brayton Cycle from the ideal cycle. The Second law efficiency of the Brayton Cycle has been found as a function of reheat and intercooling pressure ratios, total pressure ratio, intercooler, regenerator and reheater effectiveness, hot and cold side heat exchanger effectiveness, turbine and compressor efficiency and heating capacities of the heating fluid, the cooling fluid and the working fluid (air). The variation of the Second law efficiency with all these parameters has been presented. From the results, it can be seen that the Second law efficiency first increases and then decreases with increase in intercooling pressure ratio and increases with increase in reheating pressure ratio. The results show that the Second law efficiency is a very good indicator of the amount of irreversibility of the cycle.
Unsteady RANS Simulation of Film Cooling Jets in a Cross-Flow With an Improved Κ-Tau Model
Authors: Hoda Asif , Acharya Sumanta
Published: October 2013

Unsteady Reynolds Averaged Navier Stokes (URANS) simulation of film cooling jets in a cross-flow with an improved k-tau model is presented in this work. The improved model is able to reproduce the unsteady behavior of key flow structures like the horse-shoe vortex as well as demonstrates improved predictions of the vertical and lateral spreading of the film cooling jet. However, the anisotropy of the flow is not captured accurately by the Bousinesque approximation of the Reynolds stresses employed in the model and is therefore identified as a major area of improvement in the next stage of the model development.
Part-Load Performance of Gas Turbines: Part II — Multi-Point Adaptation With Compressor Map Generation and GA Optimization
Authors: Tsoutsanis E. , Li Y. G. , Pilidis P. , Newby M.
Published: October 2013

Accurate gas turbine performance simulation is a vital aid to the operational and maintenance strategy of thermal plants having gas turbines as their prime mover. Prediction of the part load performance of a gas turbine depends on the quality of the engine’s component maps. Taking into consideration that compressor maps are proprietary information of the manufacturers, several methods have been developed to encounter the above limitation by scaling and adapting component maps.

This part of the paper presents a new off-design performance adaptation approach with the use of a novel compressor map generation method and Genetic Algorithms (GA) optimization. A set of coefficients controlling a generic compressor performance map analytically is used in the optimization process for the adaptation of the gas turbine performance model to match available engine test data.

The developed method has been tested with off-design performance simulations and applied to a GE LM2500+ aeroderivative gas turbine operating in Manx Electricity Authority’s combined cycle power plant in the Isle of Man. It has been also compared with an earlier off-design performance adaptation approach, and shown some advantages in the performance adaptation.
Effect of J-Shaped Casing Treatment on Flow Stability and Performance of an Axial Compressor
Authors: Pathan Ramjan R. , Nagpurwala Quamber H. , Bhat Ananthesha
Published: October 2013

Casing Treatment (CT) is one of the passive methods to increase the stability margin of the compress and hence that of the aircraft jet engines. In this paper, a novel J-shaped axial CT slot geometry is designed and numerically analysed for its effect on the performance of a single stage NACA transonic compressor. The predicted performance of the isolated rotor was validated by comparing with the published experimental results. The predicted efficiency of the baseline transonic rotor agreed well with experimental data, but the total pressure ratio was under predicted over the entire operating range. The J-shaped CT slots, with 100% axial coverage over the rotor tip chord, were able to extend the stall mass flow rate by almost 19.45% compared to the baseline rotor, accompanied with a slight reduction in rotor efficiency by 1.42%. The high pressure air entered the slots at rotor exit and flowed back through the slots and the plenum, and ejected at the rotor inlet to energise the low momentum end wall flow. The interaction of main inlet flow and the ejected flow having large tangential component of velocity, had favourable effect on the rotor incidence angle, and hence on rotor stall margin.
A Strategy for Multi-Point Compressor Blading Using Multi-Objective Optimization
Authors: Fathi Alireza , Shadaram Abdollah , Alizadeh Mohammad
Published: October 2013

This paper introduces a framework to perform a multi-objective multipoint aerodynamic optimization for an axial compressor blade. This framework considers through-flow design requirements and mechanical and manufacturing constraints. Typically, components of a blade design system include geometry generation tools, optimization algorithms, flow solvers, and objective functions. In particular, optimization algorithms and objective functions are tuned to reduce blade design calculation cost and to match designed blade performance to the through flow design criteria and mechanical and manufacturing constrains. In the present study, geometry parameters of blade are classified to three categories. For each category, a distinct optimization loop is applied. In outer loop, Gradient-based optimization techniques are used to optimize parameters of the second category and a two-dimensional compressible viscous flow code is used to simulate the cascade fluid flow. Surface curvature optimization is carried out in inner loop, and its objective function is defined by integrating the normalized curvature and curvature slope. The genetic algorithm is used to optimize the parameters in the interior loop. To highlight the capabilities of the design method and to develop design know-how, an initial profile is optimized with three different design philosophies. The highest performance improvement in the first case is 15% reduction in loss at design incidence angle. In the second case, 16.5% increase in allowable incidence angle range, improves blade’s performance at off design conditions.
Cost-Effective Hybrid RANS-NLES Method for Jet Turbulence and Noise Prediction
Authors: Mahak M. , Tucker Paul G. , Ray Prasun K.
Published: October 2013

Jets at higher Reynolds numbers have a high concentration of energy in the small scales in the nozzle vicinity. This is challenging for LES, potentially placing severe demands on grid density. To circumvent this, we propose a novel procedure based on well known Reynolds number (Re) independence of jets. We reduce the jet Re whilst rescaling the boundary layer properties to maintain incoming boundary layer thickness consistent with high Re jet. The simulations are carried out using hybrid largeeddy simulation type of approach which is incorporated by using near wall turbulence model with modified properties. No Subgrid Scale (SGS) model is used in these simulations. Hence, they effectively become Numerical Large Eddy Simulation (NLES) with Reynolds-averaged Navier-Stokes (RANS) covering the full boundary layer region. The noise post processing is carried out using Ffowcs-Williams-Hawking (FWH) approach. The simulations are made for Mach numbers (M) of 0.75 and 0.875. The results for Overall Sound Pressure Level (OASPL) are observed to be within 2–3% accuracy range and directivity of sound is also captured accurately for both the cases. The low Re simulations hence, can be more beneficial in saving time and cost of the simulation while providing reasonably accurate results.
A Novel Approach to Design Reversible Counter Rotating Propeller Fans
Authors: Abbaszadeh Morteza , Nikpour Parizi Parvin , Taheri Ramin
Published: October 2013

Because of their high performance and unique abilities like producing none-rotating wake, Counter Rotating Propellers (C.R.P.) are being used in many advanced propulsion or ventilation systems. But due to complicated design procedure of C.R.P. fans up to now it was not possible to apply the concept in reversible systems. For the first time in this research, a new method presented to design a reversible counter rotating propeller system. This method is based on designing a basic C.R.P. by a reliable edition of blade element theory to achieve maximum performance in main rotating course and then to optimize it in order to have almost same performance in reverse rotating course. After expressing concepts of the method, a basic model is designed to ensure the capability of the presented scheme. Design outcome was a Reversible C.R.P. (R.C.R.P) system with 0.5 meter in diameter and cross section of NACA2412 airfoil. This model is evaluated by using R.S.M. turbulence method through ANSYS Fluent commercial software package. Evaluation results showed that system has efficiency of 0.85 in main course and 0.78 in reverse course by which a good performance for a small size reversible system can be captured.
Correlations of linear and nonlinear ultrasound parameters with density and microarchitectural parameters in trabecular bone
Authors: Lee Kang Il
Published: October 2013

In the present study, correlations of linear and nonlinear ultrasound parameters (speed of sound, normalized broadband ultrasound attenuation, and nonlinear parameter B/A) with bone mineral density and microarchitectural parameters were investigated in 28 bovine femoral trabecular bone samples in vitro. All three ultrasound parameters exhibited relatively high correlation coefficients with the indexes of bone quantity (bone mineral density and bone volume fraction) and lower correlation coefficients with the remaining microarchitectural parameters. These results suggest that B/A, in addition to speed of sound and attenuation, may have potential as an index for the assessment of bone status and osteoporosis.
The Hippo Signaling Pathway Interactome
Authors: Kwon Young , Vinayagam Arunachalam , Sun Xiaoyun , Dephoure Noah , Gygi Steven P. , Hong Pengyu , Perrimon Norbert
Published: October 2013

Dissecting Hippo Interactions

The Hippo signaling pathway plays key roles in many processes, from cell proliferation and cell death to regulation of stem cells and cancer cells.

Kwon
et al.

(p.
737
, published 10 October) attempted to systematically identify all components of the pathway. A protein-protein interaction screen identified more than 200 interactions among approximately 150 proteins. A protein identified in the screen, Leash, restrained the activity of the transcriptional coactivator Yorkie, which regulates gene expression in response to Hippo signaling.
2000 Years of Parallel Societies in Stone Age Central Europe
Authors: Bollongino Ruth , Nehlich Olaf , Richards Michael P. , Orschiedt Jörg , Thomas Mark G. , Sell Christian , Fajkošová Zuzana , Powell Adam , Burger Joachim
Published: October 2013

Farming or Fishing

Evidence has been mounting that most modern European populations originated from the immigration of farmers who displaced the hunter-gatherers of the Mesolithic.

Bollongino
et al.

(p.
479
, published online 10 October) present analyses of palaeogenetic and isotopic data from Neolithic human skeletons from the Blätterhöhle burial site in Germany. The analyses identify a Neolithic freshwater fish–eating hunter-gatherer group, living contemporaneously and in close proximity to a Neolithic farming group. While there is some evidence that hunter-gatherer women may have admixed into the farming population, it appears likely that marriage or cultural boundaries between the groups persisted for over two millennia. Thus, the transition from the Mesolithic involved a more complex pattern of coexistence among humans of different genetic origins and cultures in the Neolithic, rather than a more abrupt transition.
Draft Genome Sequence of Lactobacillus plantarum Strain AY01, Isolated from the Raw Material of Fermented Goat Milk Cheese
Authors: Li Xiao-Ran , Gong Fu-Ming , Zheng Hua-Jun , Zhang Zhong-Hua , Luo Yi-Yong , Liu Chen-Jian
Published: October 2013

Lactobacillus plantarum
is an important probiotic that is isolated mostly from fermented foods. Here, we report the first draft genome sequence of
L. plantarum
strain AY01, isolated from the raw material of fermented goat milk cheese. This bacterium, with optimum growth at 30°C, has a G+C content of 43.68%.
Complete Genome Sequence of a Nephropathogenic Infectious Bronchitis Virus Strain Isolated in China
Authors: Yang Jing-tian , Ma Bing-cun
Published: October 2013

Infectious bronchitis virus (IBV) causes tremendous economic losses to the poultry industry. Here, we report the complete genome analysis results for a new natural recombination nephropathogenic IBV strain named SAIBK, which was isolated in the Sichuan province of China in 2005.
Identification of a Genotype IX Newcastle Disease Virus in a Guangxi White Duck
Authors: Xie Zhixun , Xie Liji , Xu Zongli , Liu Jiabo , Pang Yaoshan , Deng Xianwen , Xie Zhiqin , Fan Qing , Luo Sisi
Published: October 2013

We report the complete genomic sequence of a novel Newcastle disease virus (NDV) strain, duck/China/Guangxi19/2011, isolated from a white duck in Guangxi Province, southern China. Phylogenetic analysis based on a fusion gene comparison with different NDV strains revealed that duck/China/Guangxi19/2011 is phylogenetically close to genotype IX NDV, and the deduced amino acid sequence of the fusion protein cleavage site was 112R-R-Q-R-R-F117. The whole nucleotide sequence had the highest homology (99.7%) to the sequence of strain F48E8 (GenBank accession number FJ436302). This study will help us understand the epidemiology and molecular characteristics of genotype IX Newcastle disease virus in ducks.
Overdrive pacing in a patient with incessant torsades de pointes
Authors: Overbey Adam N , Austin Andrea , Seidensticker Daniel F , Lin Andrew H
Published: October 2013

A 75-year-old man presented to the emergency department (ED) for syncope and was found to have intermittent runs of torsades de pointes (TdP). The patient had a medical history significant for disseminated coccidiomycosis and was on prophylactic fluconazole. Forty-eight hours prior to presentation, the patient had intractable nausea and vomiting and was unable to take anything orally. He eventually presented to the ED with severe hypokalaemia and hypomagnesaemia with repeat symptomatic runs of TdP, which required overdrive transvenous pacing. During the patient’'s admission, his electrolytes were aggressively replete. Fluconazole was discontinued, and prior to discharge, the patient recovered fully with ECGs showing a normalisation of the QT interval.
A rare cystic lesion of the neck: parathyroid cyst
Authors: Kaplanoglu Veysel , Kaplanoglu Hatice , Cılız Deniz Sözmen , Duran Semra
Published: October 2013

Parathyroid cysts are rarely observed neck masses. Their physical examination is not specific and preoperative diagnosis is usually difficult. Imaging findings and ultrasound-guided fine-needle aspiration with hormone analysis evaluation are important diagnostic criteria. A 48-year-old female patient admitted to our hospital with a symptom of swelling on the left side of the neck was diagnosed with parathyroid cyst by imaging methods (ultrasonography, MRI, parathyroid scintigraphy) and laboratory findings. Fine-needle aspiration biopsy was performed and because of relapse on the follow-up sclerotherapy was planned. Our aim in this study was to present the radiological findings of this case of parathyroid cyst.
Is rapid hepatitis C virus testing from corpses a screening option for index persons who have died after mass-casualty incidents in high-prevalence settings in the field?
Authors: Hagen Ralf M , Wulff B , Loderstaedt U , Fengler I , Frickmann H , Schwarz N G , Polywka S
Published: October 2013

Introduction

We tested a commercially available rapid hepatitis C virus (HCV) test assay for its potential use for analyses of corpses as a screening option for index persons who have died after mass-casualty incidents in high-prevalence settings in the field.

Materials and methods

50 blood samples were drawn from 16 recently deceased confirmed HCV-positive patients whose corpses were stored at 4°C in the mortuary and were analysed at admission and up to 48 h post mortem by rapid serological testing using the ImmunoFlow HCV test (Core Diagnostics, Birmingham, UK) in comparison with automated serological assays and PCR. Samples from 50 HCV-negative corpses were also analysed.

Results

The blood of only four of the 16 HCV-positive corpses reacted clearly with the ImmunoFlow HCV test, while in five cases the result was only weakly reactive and three cases showed very weak reactivity. Four of the infected corpses showed initially negative results, three of which became very weakly reactive 48 h post mortem. 49 out of 50 samples (98%) from HCV-negative corpses tested negative.

Discussion

The rapid test system we investigated showed insufficient sensitivity regarding the identification of HCV positivity. Automated serological testing or PCR should be preferred if it is realistically available in the deployed military setting.
Efficacy of dimetinden and hydroxyzine/chlorpheniramine in atopic dogs: a randomised, controlled, double‐blinded trial
Authors: Eichenseer M. , Johansen C. , Mueller R. S.
Published: October 2013

Antihistaminic drugs are commonly used as symptomatic therapy of atopic dermatitis in dogs. Unfortunately, their clinical benefit is largely unsubstantiated. In a double‐blinded, placebo‐controlled, cross‐over trial, the influence of dimetinden and of a combination of chlorpheniramine and hydroxyzine on pruritus and lesions was evaluated in 19 dogs. They were treated with either product or a placebo orally for 14 days, each time followed by a 14‐day washout period. Before and after each period, the dogs were examined and the Canine Atopic Dermatitis Extent and Severity Index (CADESI) determined by a clinician, and the pruritus and general condition by the owner. Dimetinden improved the pruritus significantly (P=0.014) but not the CADESI (P=0.087), the combination of hydroxyzine and chlorpheniramine improved the CADESI (P=0.049) and pruritus (P=0.05) significantly. Ten of 17 dogs improved by more than 25 per cent in pruritus with the combination of hydroxyzine and chlorpheniramine, 12 of 18 with dimetindenmaleate and only 2 of 19 with placebo. Antihistamines can help to reduce pruritus in atopic dogs, but in most cases, the improvement is limited and additional treatment may be needed.
Marbled Murrelets (Brachyramphus marmoratus) foraging with gray whales (Eschrichtius robustus) off Vancouver Island, British Columbia
Authors: Muirhead K.A. , Malcolm C.D. , Duffus D.A.
Published: October 2013

Seabirds are known to associate with marine mammals to facilitate prey capture. These occur when mammals either force prey near the surface or provide small scraps of larger prey victims. Gray whales (Eschrichtius robustus (Lilljeborg, 1861)) have been observed to provide invertebrate prey to a variety of seabird species; however, there are no published reports of Marbled Murrelets (Brachyramphus marmoratus (Gmelin, 1789)) feeding in association with gray whales. We observed Marbled Murrelets foraging within several metres of gray whales off Vancouver Island, British Columbia, feeding on epibenthic zooplankton in 2006 and 2008. Join-count statistics identified significant clustering (p = 0.1) of 258 Marbled Murrelets within 300 m of 39 feeding gray whales in June of 2006, and no association between 3 gray whales and 34 Marbled Murrelets in June and July of 2008, marking a foraging association conditional on the abundance of both gray whales and their prey, but potentially significant to Marbled Murrelet survival and fecundity.