bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of Constant and Variable Amplitude Strain-Life Data Using a Novel Probabilistic Weibull Regression Model
Authors: Pinto Hernán , De Jesus Abílio M. P. , Fernández-Canteli Alfonso , Castillo Enrique , Pereira Hélder F. S. G.
Published: October 2010

The relation between the total strain amplitude and the fatigue life measured in cycles is usually given as strain-life curves based on the former proposals of Basquin, for the elastic strain-life, and Coffin–Manson, for the plastic strain-life. In this paper, a novel Weibull regression model, based on an existing well established Weibull model for the statistical assessment of stress-life fatigue data, is proposed for the probabilistic definition of the strain-life field. This approach arises from sound statistical and physical assumptions and not from an empirical proposal insufficiently supported. It provides an analytical probabilistic definition of the whole strain-life field as quantile curves, both in the low-cycle and high-cycle fatigue regions. The proposed model deals directly with the total strain, without the need of separating its elastic and plastic strain components, permit dealing with run-outs, and can be applied for probabilistic lifetime prediction using damage accumulation. The parameters of the model can be estimated using different well established methods proposed in the fatigue literature, in particular, the maximum likelihood and the two-stage methods. In this work, the proposed model is applied to analyze fatigue data, available for a pressure vessel material—the P355NL1 steel—consisting of constant amplitude, block, and spectrum loading, applied to smooth specimens, previously obtained and published by authors. A new scheme to deal with variable amplitude loading in the background of the proposed regression strain-life Weibull model is described. The possibility to identify the model constants using both constant amplitude and two-block loading data is discussed. It is demonstrated that the proposed probabilistic model is able to correlate the constant amplitude strain-life data. Furthermore, it can be used to correlate the variable amplitude fatigue data if the model constants are derived from two-block loading data. The proposed probabilistic regression model is suitable for reliability analysis of notched details in the framework of the local approaches.
An Approach to Derive Primary Bending Stress From Finite Element Analysis for Pressure Vessels and Applications in Structural Design
Authors: Gao Bingjun , Chen Xiaohui , Shi Xiaoping , Dong Junhua
Published: October 2010

An important issue in engineering application of the “design by analysis” approach in pressure vessel design is how to decompose an overall stress field obtained by finite element analysis into different stress categories defined in the ASME B&PV Codes III and VIII-2. In many pressure vessel structures, it is difficult to obtain PL+Pb due to the lack of information about primary bending stress. In this paper, a simple approach to derive the primary bending stress from the finite element analysis was proposed with application examples and verifications. According to the relationship of the bending stress and applied loads or the relationship of the bending stress and displacement agreement, it is possible to identify loads causing primary bending stress for typical pressure vessel structures. By applying the load inducing primary bending stress alone and necessary superposition, the primary bending stress and corresponding stress intensity PL+Pb can be determined for vessel design, especially for axisymmetric problems.
Technical Basis for Acceptance/Rejection Criteria for Flaws in High Pressure Gas Cylinder
Authors: Rana Mahendra D. , Smith John H. , Holroyd Henry
Published: October 2010

The objective of this paper is to present the technical basis used for developing acceptance/rejection limits for seamless, high pressure gas cylinders that can be used at the time of retesting the cylinders. The development of acceptance/rejection limits for cylinders is done in three steps. First, the “critical flaw sizes” (e.g., depth and length or area) for selected types of flaws are established by an analysis procedure that has been verified by experimental tests. Next the “allowable flaw sizes” are calculated by modifying (reducing) the size of the critical flaw sizes for each cylinder by adjusting for fatigue crack growth that may occur during the use of the cylinder. Finally, the “acceptance/rejection criteria” is established to take into account other factors, such as all the expected operating conditions that the cylinders may see in service, and the reliability and detectability of the specific inspection equipment to be used and to adjust the allowable flaw sizes to provide an additional margin of safety. This acceptance/rejection limits have been incorporated in a recently published ISO Technical Report No. TR 22694:2008 (2007, “Gas Cylinders—Methods for Establishing Acceptance/Rejection Criteria for Flaws in Seamless Steel and Aluminum Alloy Cylinders at Time of Periodic Inspection and Requalification,” The International Standards Organization, Geneva, Switzerland, Technical Report No. 22694). In this work, the API 579 “Recommended Practice for Fitness-for-Service” (2000, API 579: Recommended Practice for Fitness-for-Service, 1st ed., American Petroleum Institute, Washington, DC) was used to calculate the critical flaw sizes for a range of cylinder sizes and strength levels. For this study, the critical flaw size is defined as the size of the flaw that will cause the cylinders to fail at the test pressure of the cylinder. The results of flawed-cylinder burst tests were used to experimentally verify the calculated critical flaw sizes. The allowable flaw sizes were then calculated by using well established fatigue crack growth rate data for steel and aluminum alloys to allow for the expected amount of fatigue crack growth that may occur during the specified retesting intervals. A limited number of tests was conducted to verify the allowable flaw size calculations. Further adjustments are made to the allowable flaw sizes to define the acceptance/rejection criteria to be used during cylinder retesting.
On the Buckling of Functionally Graded Cylindrical Shells Under Combined External Pressure and Axial Compression
Authors: Khazaeinejad P. , Najafizadeh M. M. , Jenabi J. , Isvandzibaei M. R.
Published: October 2010

The stability problem of a circular cylindrical shell composed of functionally graded materials with elasticity modulus varying continuously in the thickness direction under combined external pressure and axial compression loads is studied in this paper. The formulation is based on the first-order shear deformation theory. A load interaction parameter is defined to express the combination of applied axial compression and external pressure. The stability equations are derived by the adjacent equilibrium criterion method. These equations are employed to analyze the buckling behavior and obtain the critical buckling loads. A detailed numerical study is carried out to bring out the effects of the power law index of functionally graded material, load interaction parameter, thickness ratio, and aspect ratio on the critical buckling loads. The validity of the present analysis was checked by comparing the present results with those results available in literature.
A New Approach of Reliability Design For Creep Rupture Property
Authors: Zhao Jie , Li Dong-ming , Fang Yuan-yuan , Zhu Shi-jie
Published: October 2010

Generally, creep rupture data of a heat-resistant steel can be compressed into a narrow band by using a temperature-time parametric method such as the Larson–Miller or Manson–Haferd method. In order to describe the scattering of the data, the current paper proposes a “Z parameter” method to represent the magnitude of the deviation of the rupture data to master curve. Statistical analysis shows that the scattering of the Z parameter for several types of steels is supported by normal distribution. Using this method, it is possible to achieve unified analysis of the creep rupture data in various temperature and stress conditions. Stress-time temperature parameter-reliability curves (σ-TTP-R curves), stress-rupture time-reliability curves (σ-tr-R curves), and allowable stress-temperature-reliability curves ([σ]-T-R curves) are proposed, which could embrace the reliability concept into creep rupture property design.
Plastic Analysis for Cylindrical Vessels Under In-Plane Moment on the Nozzle
Authors: Wu B. H. , Sang Z. F. , Widera G. E. O.
Published: October 2010

The objective of this paper is to determine the plastic limit moment for cylindrical vessels with a nozzle under in-plane moment loading. Three full scale test models with different d/D ratios were fabricated for the experiment. A three-dimensional nonlinear finite element analysis was also performed. The plastic limit moment of the cylindrical vessel-nozzle connections was determined approximately by the twice-elastic-slope criterion. The results indicate that the plastic limit moments obtained by the experiment and finite element analysis are in good agreement. On the basis of the above results, a parametric analysis of the plastic limit moment for cylindrical vessels under in-plane moment on the nozzle was carried out, and an empirical formula is proposed. The results can serve as a supplement to the available data of plastic limit load for cylindrical vessel-nozzle connection structures under external load.
Application of Manson–Haferd and Larson–Miller Methods in Creep Rupture Property Evaluation of Heat-Resistant Steels
Authors: Zhao Jie , Li Dong-Ming , Fang Yuan-Yuan
Published: October 2010

The current paper discusses the selection of Manson–Haferd and Larson–Miller constants on correlation results of creep rupture property in several heat-resistant steels. It indicates that the change in Larson–Miller constant CLM has obvious effect on the predicting result of rupture life and the optimal CLM values will depend on materials and the optimal ranges of the values are narrow. However, for Manson–Haferd constants Ta and log ta, they are at least phenomenally not independent variables but show a linear relationship: log ta=27.015−0.0267Ta. It is shown that the values of Manson–Haferd constants (Ta,log ta) can be selected in a wide range with desirable correlation accuracy and a set of Manson–Haferd constant (Ta=450, log ta=15) is recommended to correlate the creep rupture data.
Design Parameters for an Aircraft Engine Exit Plane Particle Sampling System
Authors: Wong Hsi-Wu , Yu Zhenhong , Timko Michael T. , Herndon Scott C. , Blanco Elena de la Rosa , Miake-Lye Richard C. , Howard Robert P.
Published: October 2010

The experimental data and numerical modeling were utilized to investigate the effects of exhaust sampling parameters on the measurements of particulate matter (PM) emitted at the exit plane of gas-turbine engines. The results provide guidance for sampling system design and operation. Engine power level is the most critical factor that influences the size and quantity of black carbon soot particles emitted from gas-turbine engines and must be considered in sampling system design. The results of this investigation indicate that the available soot surface area significantly affects the amount of volatile gases that can condense onto soot particles. During exhaust particle measurements, a dilution gas is typically added to the sampled exhaust stream to suppress volatile particle formation in the sampling line. Modeling results indicate that the dilution gas should be introduced upstream before a critical location in the sampling line that corresponds to the onset of particle formation microphysics. Also, the dilution gas should be dry for maximum nucleation suppression. In most aircraft PM emissions measurements, the probe-rake systems are water cooled and the sampling line may be heated. Modeling results suggest that the water cooling of the probe tip should be limited to avoid overcooling the sampling line wall temperature and, thus, minimize additional particle formation in the sampling line. The experimental data show that heating the sampling lines will decrease black carbon and sulfate PM mass and increase organic PM mass reaching the instruments. Sampling line transmission losses may prevent some of the particles emitted at the engine exit plane from reaching the instruments, especially particles that are smaller in size. Modeling results suggest that homogeneous nucleation can occur in the engine exit plane sampling line. If newly nucleated particles, typically smaller than 10 nm, are indeed formed in the sampling line, sampling line particle losses provide a possible explanation, in addition to the application of dry diluent, that they are generally not observed in the PM emissions measurements.
Vibration Analysis of a Nonlinear System With Cyclic Symmetry
Authors: Grolet Aurélien , Thouverez Fabrice
Published: October 2010

This work is devoted to the study of nonlinear dynamics of structures with cyclic symmetry under geometrical nonlinearity using the harmonic balance method (HBM). In order to study the influence of the nonlinearity due to large deflection of blades, a simplified model has been developed. It leads to nonlinear differential equations of the second order, linearly coupled, in which the nonlinearity appears by cubic terms. Periodic solutions in both free and forced cases are sought by the HBM coupled with an arc length continuation and stability analysis. In this study, specific attention has been paid to the evaluation of nonlinear modes and to the influence of excitation on dynamic responses. Indeed, several cases of excitation have been analyzed: punctual one and tuned or detuned low engine order. This paper shows that for a localized, or sufficiently detuned, excitation, several solutions can coexist, some of them being represented by closed curves in the frequency-amplitude domain. Those different kinds of solution meet up when increasing the force amplitude, leading to forced nonlinear localization. As the closed curves are not tied with the basic nonlinear solution, they are easily missed. They were calculated using a sequential continuation with the force amplitude as a parameter.
Flame Response Mechanisms Due to Velocity Perturbations in a Lean Premixed Gas Turbine Combustor
Authors: Jones Brian , Lee Jong Guen , Quay Bryan D. , Santavicca Domenic A.
Published: October 2010

The response of turbulent premixed flames to inlet velocity fluctuations is studied experimentally in a lean premixed, swirl-stabilized, gas turbine combustor. Overall chemiluminescence intensity is used as a measure of the fluctuations in the flame’s global heat release rate, and hot wire anemometry is used to measure the inlet velocity fluctuations. Tests are conducted over a range of mean inlet velocities, equivalence ratios, and velocity fluctuation frequencies, while the normalized inlet velocity fluctuation (V′/Vmean) is fixed at 5% to ensure linear flame response over the employed modulation frequency range. The measurements are used to calculate a flame transfer function relating the velocity fluctuation to the heat release fluctuation as a function of the velocity fluctuation frequency. At low frequency, the gain of the flame transfer function increases with increasing frequency to a peak value greater than 1. As the frequency is further increased, the gain decreases to a minimum value, followed by a second smaller peak. The frequencies at which the gain is minimum and achieves its second peak are found to depend on the convection time scale and the flame’s characteristic length scale. Phase-synchronized CH∗ chemiluminescence imaging is used to characterize the flame’s response to inlet velocity fluctuations. The observed flame response can be explained in terms of the interaction of two flame perturbation mechanisms, one originating at flame-anchoring point and propagating along the flame front and the other from vorticity field generated in the outer shear layer in the annular mixing section. An analysis of the phase-synchronized flame images show that when both perturbations arrive at the flame at the same time (or phase), they constructively interfere, producing the second peak observed in the gain curves. When the perturbations arrive at the flame 180 degrees out-of-phase, they destructively interfere, producing the observed minimum in the gain curve.
Derivation of Temperature-Estimation Equation Based on Microstructural Changes in Coatings of In-Service Blades of Gas Turbines
Authors: Okada Mitsutoshi , Hisamatsu Tohru , Fujioka Terutaka
Published: October 2010

A CoNiCrAlY-coated blade of an in-service gas turbine is analyzed, and a diffusion layer is formed along the boundary between the coating and the substrate due to the interdiffusion in the middle and tip of the blade. Such a layer is not observed in the vicinity of the blade root because of a comparatively low temperature during the operation. Coated specimens are prepared from the portions of the blade devoid of the diffusion layers, and the specimens are exposed to a high temperature in air. On the basis of the increase in the diffusion layer thickness, an equation for estimating the temperature of the blade is derived. An analysis of another in-service blade with a thermal barrier coating is carried out. The aluminum content decreases below the bond coat surface due to Al diffusion caused by the Al-oxide formation. This results in the formation of an Al-decreased layer (ADL) along the leading and trailing edges. The ADL is not observed at the center of the blade chord. The specimens are extracted from the portions of the blade that are devoid of ADL, and they are subjected to a high temperature in air. On the basis of the increase in the ADL thickness, a temperature-estimation equation is derived.
Experiments on the Transient Performance of an Adaptive Multi-Objective Controller for Rotating Machinery
Authors: Sahinkaya M. Necip , Abulrub Abdul-Hadi G. , Keogh Patrick S. , Burrows Clifford R.
Published: October 2010

This paper describes an experimental assessment of the transient performance of a multi-objective adaptive approach to the control of flexible rotors. This is applicable to any arrangement of controllable bearings or actuators. In the case reported here, the rotor is supported by active magnetic bearings. The theory underlying the controller is outlined. The objectives include minimization of the forces transmitted to the base while restricting rotor vibrations to a user-defined limit. A third objective is to prevent rotor contact with the auxiliary bearings, which are used to protect the active elements. These objectives are met by a two-stage weighting strategy followed by the adaptive control of two parameters that automatically and continuously adjust the weightings of individual objective functions to satisfy user-defined performance criteria.
Ultralow-Emission Combustion and Control System Installation Into Mature Power Plant Gas Turbines
Authors: Benoit Jeffrey A. , Ellis Charles , Cook Joseph
Published: October 2010

The search for power plant sustainability options continues as regulating agencies exert more stringent industrial gas turbine emission requirements on operators. Purchasing power for resale, decomissioning current capabilities altogether, and repowering by replacing or converting existing equipment to comply with emission standards are economic-driven options contemplated by many mature gas turbine operators. One Las Vegas, NV operator, NV Energy, with four natural gas-fired W501B6 combined cycle units at their Edward W. Clark Generating Station, was in this situation in 2006. The units, originally configured with diffusion flame combustion systems, were permitted at 103 ppm NOx with regulatory mandates to significantly reduce NOx emissions to below 5 ppm by the end of 2009. Studies were conducted by the operator to evaluate the economic viability of using a selective catalytic reduction system, which would have forced significant modifications to the exhaust system and heat recovery steam generator, or convert the turbines to operate with dry low-emission combustion systems. Based on life cycle cost and installation complexity, the ultralow-emission combustion system was selected. This technical paper focuses on a short summary of the end user considerations in downselecting options, the ultralow emissions technology, and key features employed to achieve these low emissions, an overview of the conversion scope and a review and description of the control technology employed. Finally, a technical discussion of the low-emission operational flexibility will be provided including performance results of the converted units.
Prediction of Aeroacoustic Resonance in Cavities of Hole-Pattern Stator Seals
Authors: Liliedahl David N. , Carpenter Forrest L. , Cizmas Paul G. A.
Published: October 2010

A Reynolds-averaged Navier–Stokes (RANS) solver developed in-house was used to simulate grazing channel flow past single and multiple cavities. The objective of this investigation was to predict fluid instabilities in hole-pattern stator seals. The numerical results generated with the RANS solver showed good agreement with those obtained using a commercial large eddy simulation code. In addition, the numerical results agreed well with experimental data. Rossiter’s formula, a popular semi-empirical model used to predict frequencies of hole-tone acoustic instabilities caused by grazing fluid flow past open cavities, was modified using the RANS solver results to allow for its application to channel flows. This was done by modifying the empirical constant κ, the ratio of vortex velocity, and the freestream velocity. The dominant frequencies predicted using Rossiter’s formula with the new κ value matched well with the experimental data for hole-pattern stator seals. The RANS solver accurately captured the salient features of the flow/acoustic interaction and predicted well the dominant acoustic frequencies measured in an experimental investigation. The flow solver also provided detailed physical insight into the cavity flow instability mechanism.
Performance Benefits of a Portable Hybrid Micro-Gas Turbine Power System for Automotive Applications
Authors: Christodoulou Fanos , Giannakakis Panagiotis , Kalfas Anestis I.
Published: October 2010

The lower fuel burn and pollutant emissions of hybrid electric vehicles give a strong motivation and encourage further investigations in this field. The know-how on hybrid vehicle technology is maturing, and the reliability of such power schemes is being tested in the mass production. The current research effort is to investigate novel configurations, which could achieve further performance benefits. This paper presents an assessment of a novel hybrid configuration comprising a micro-gas turbine, a battery bank, and a traction motor, focusing on its potential contribution to the reduction in fuel burn and emissions. The power required for the propulsion of the vehicle is provided by the electric motor. The electric power is stored by the batteries, which are charged by a periodic function of the micro-gas turbine. The micro-gas turbine starts up when the battery depth of discharge exceeds 80%, and its function continues until the batteries are full. The performance of the vehicle is investigated using an integrated software platform. The calculated acceleration performance and fuel economy are compared with those of conventional vehicles of the same power. The sensitivity of the results to the variation in the vehicle parameters such as mass, kinetic energy recovery, and battery type is calculated to identify the conditions under which the application of this hybrid technology offers potential benefits. The results indicate that if no mass penalties are incurred by the installation of additional components, the fuel savings can exceed 23%. However, an increase in the vehicle’s weight can shrink this benefit especially in the case of light vehicles. Lightweight batteries and kinetic energy recovery systems are deemed essential, enabling technologies for a realistic application of this hybrid system.
Incorporation of Strain Hardening Effect Into Simplified Limit Analysis
Authors: Gudimetla P. S. Reddy , Adibi-Asl R. , Seshadri R.
Published: October 2010

In this paper, a method for determining limit loads in the components or structures by incorporating strain hardening effects is presented. This has been done by including a certain amount of the strain hardening into limit load analysis, which normally idealizes the material to be elastic perfectly plastic. Typical strain hardening curves such as bilinear hardening and Ramberg–Osgood material models are investigated. This paper also focuses on the plastic reference volume correction concept to determine the active volume participating in plastic collapse. The reference volume concept in combination with mα-tangent method is used to estimate lower-bound limit loads of different components. Lower-bound limit loads obtained compare well with the nonlinear finite element analysis results for several typical configurations with/without crack.
Safety Evaluation of the HTTR-IS Nuclear Hydrogen Production System
Authors: Sato Hiroyuki , Ohashi Hirofumi , Tazawa Yujiro , Sakaba Nariaki , Tachibana Yukio
Published: October 2010

The establishment of a safety evaluation method is one of the key issues for the nuclear hydrogen production demonstration since fundamental differences in the safety philosophy between nuclear plants and chemical plants exist. In the present study, a practical safety evaluation method, which enables to design, construct, and operate hydrogen production plants under conventional chemical plant standards, is proposed. An event identification is conducted for the HTTR-IS system, a nuclear hydrogen production system by thermochemical water splitting iodine-sulfur process (IS process) utilizing the heat from the high temperature engineering test reactor (HTTR) in order to select abnormal events, which would change the scenario and quantitative results of the evaluation items from the existing HTTR safety evaluation. In addition, a safety analysis is performed for the identified events. The results of safety analysis for the identified five anticipated operational occurrences (AOOs) and three accidents (ACDs) show that evaluating items such as a primary cooling system pressure, temperatures of heat transfer tubes at pressure boundary, etc., do not exceed the acceptance criteria during the scenario. In addition, the increase of peak fuel temperature is small in the most severe case and therefore, the reactor core was not damaged and cooled sufficiently. These results will contribute to the safety review from the government and demonstration of the nuclear production of hydrogen.
Probing the Ultimate Limit of Fiber-Optic Strain Sensing
Authors: Gagliardi G. , Salza M. , Avino S. , Ferraro P. , De Natale P.
Published: October 2010

Enhanced Strain Sensitivity

The ability to measure tiny deformations in length is useful for many disciplines, from largescale structural engineering to DNA analysis with optical tweezers. The most sensitive strain sensors are those using optical interferometers, which can detect small changes at the scale of visible wavelengths. Using an optical frequency comb to stabilize the output of a diode laser, and as a highly accurate ruler to determine small changes in length of an optic fiber sensor,

Gagliardi
et al.

(p.
1081
, published online 28 October) showed that sensitivity can be enhanced by several orders of magnitude. Such combined technology should provide for a new generation of high-performance sensors.
The transformation of (bio)ethics expertise in a world of ethical pluralism
Authors: Kovács József
Published: October 2010

Today, bioethics experts have an increasing role in public life. However, the question arises: what does bioethics expertise really mean? Can there be such a thing in our globalised world characterised by ethical pluralism? I will argue that bioethics as a discipline represents the transformation of ethics expertise from a hard to a soft form of it. Bioethics was born as a reaction to the growing awareness of ethical pluralism, and it denied the hard form of normative–prescriptive ethics expertise (the ability to determine what is the right course of action for others), particularly in its medical ethics form. In contrast, the traditional medical ethics model, and pre-modern societies in general, believed in hard normative ethics expertise. From this followed the characteristic paternalism of traditional medical practice: if physicians were experts in moral matters as well, if they knew what the right course of action to choose was, then they had a right to benevolently force this course of action on their patients. The remnants of this doctrine, although rarely stated explicitly, still can often be seen in clinical practice. The whole bioethics movement can be seen as a radical denial of the doctrine of physician's hard expertise in moral matters. Bioethics, however, represents a type of soft ethics expertise (mainly value sensitivity). Hence follows the seeming paradox of bioethics expertise: bioethics is both a denial of ethics expertise (in its hard form) as well as a type of (soft) ethics expertise.
Medicine and the Holocaust: a visit to the Nazi death camps as a means of teaching medical ethics in the Israel Defense Forces Medical Corps
Authors: Oberman Anthony S , Brosh-Nissimov Tal , Ash Nachman
Published: October 2010

A novel method of teaching military medical ethics, medical ethics and military ethics in the Israel Defense Force (IDF) Medical Corps, essential topics for all military medical personnel, is discussed. Very little time is devoted to medical ethics in medical curricula, and even less to military medical ethics. Ninety-five per cent of American students in eight medical schools had less than 1 h of military medical ethics teaching and few knew the basic tenets of the Geneva Convention. Medical ethics differs from military medical ethics: the former deals with the relationship between medical professional and patient, while in the latter military physicians have to balance between military necessity and their traditional priorities to their patients. The underlying principles, however, are the same in both: the right to life, autonomy, dignity and utility. The IDF maintains high moral and ethical standards. This stems from the preciousness of human life in Jewish history, tradition and religious law. Emphasis is placed on these qualities within the Israeli education system; the IDF teaches and enforces moral and ethical standards in all of its training programmes and units. One such programme is ‘Witnesses in Uniform’ in which the IDF takes groups of officers to visit Holocaust memorial sites and Nazi death camps. During these visits daily discussions touch on intricate medical and military ethical issues, and contemporary ethical dilemmas relevant to IDF officers during active missions.
Ethical and legal acceptability of the use of neuromuscular blockers (NMBs) in connection with abstention decisions in Dutch NICUs: interviews with neonatologists
Authors: Moratti Sofia
Published: October 2010

Background

In the Netherlands, using drugs to deliberately end the life of a severely defective newborn baby who is in extreme suffering can be permissible under very precise circumstances. This does not mean that all Dutch neonatologists are willing to engage in such behaviour. This paper discusses the use of neuromuscular blockers (NMBs) in connection with abstention decisions in neonatology and the boundaries between ‘deliberate ending of life’ and other end-of-life decisions. These boundaries are of paramount importance because, of all end-of-life decisions, only ‘deliberate ending of life’ must be reported by the responsible doctor and exposes him to the risk of being prosecuted.

Methods

14 Dutch neonatologists were presented with a hypothetical case of a severely asphyxiated baby who faces a long dying process after withdrawal of ‘medically futile’ (zinloos) life-sustaining ventilation. Doctors were asked whether it is acceptable to administer NMBs in this situation and whether such behaviour should be reported.

Results and conclusions

Doctors' responses were heterogeneous, showing that the acceptability of using NMBs in certain situations and the boundaries between end-of-life decisions are currently a subject of discussion among Dutch neonatologists. Many respondents reported feeling threatened by the potential involvement of the criminal law authorities in the system of control over ‘deliberate ending of life’.
Life support and euthanasia, a perspective on Shaw's new perspective
Authors: Busch Jacob , Rodogno Raffaele
Published: October 2010

It has recently been suggested by Shaw (2007) that the distinction between voluntary active euthanasia, such as giving a patient a lethal overdose with the intention of ending that patient's life, and voluntary passive euthanasia, such as removing a patient from a ventilator, is much less obvious than is commonly acknowledged in the literature. This is argued by suggesting a new perspective that more accurately reflects the moral features of end-of-life situations. The argument is simply that if we consider the body of a mentally competent patient who wants to die, a kind of ‘unwarranted’ life support, then the distinction collapses. We argue that all Shaw has provided is a perspective that makes the conclusion that there is little distinction between voluntary active euthanasia and voluntary passive euthanasia only seemingly more palatable. In doing so he has yet to convince us that this perspective is superior to other perspectives and thus more accurately reflects the moral features of the situations pertaining to this issue.
Authoritarian versus responsive communitarian bioethics
Authors: Etzioni Amitai
Published: October 2010

A communitarian approach to bioethics adds a core value to a field that is often more concerned with considerations of individual autonomy. Some interpretations of liberalism put the needs of the patient over those of the community; authoritarian communitarianism privileges the needs of society over those of the patient. Responsive communitarianism's main starting point is that we face two conflicting core values, autonomy and the common good, and that neither should be a priori privileged and that we have principles and procedure that can be used to work out this conflict but not to eliminate it. Additionally, it favours changing behaviour mainly through the creation of norms and by drawing on informal social control rather than by coercion.
Are teamwork and professional autonomy compatible, and do they result in improved hospital care?
Authors: Rafferty A M , Ball J , Aiken L H
Published: October 2010

A postal questionnaire survey of 10 022 staff nurses in 32 hospitals in England was undertaken to explore the relationship between interdisciplinary teamwork and nurse autonomy on patient and nurse outcomes and nurse assessed quality of care. The key variables of nursing autonomy, control over resources, relationship with doctors, emotional exhaustion, and decision making were found to correlate with one another as well as having a relationship with nurse assessed quality of care and nurse satisfaction. Nursing autonomy was positively correlated with better perceptions of the quality of care delivered and higher levels of job satisfaction. Analysis of team working by job characteristics showed a small but significant difference in the level of teamwork between full time and part time nurses. No significant differences were found by type of contract (permanent v short term), speciality of ward/unit, shift length, or job title. Nurses with higher teamwork scores were significantly more likely to be satisfied with their jobs, planned to stay in them, and had lower burnout scores. Higher teamwork scores were associated with higher levels of nurse assessed quality of care, perceived quality improvement over the last year, and confidence that patients could manage their care when discharged. Nurses with higher teamwork scores also exhibited higher levels of autonomy and were more involved in decision making. A strong association was found between teamwork and autonomy; this interaction suggests synergy rather than conflict. Organisations should therefore be encouraged to promote nurse autonomy without fearing that it might undermine teamwork.
A randomised controlled trial of proactive telephone counselling on cold-called smokers' cessation rates
Authors: Tzelepis Flora , Paul Christine L , Wiggers John , Walsh Raoul A , Knight Jenny , Duncan Sarah L , Lecathelinais Christophe , Girgis Afaf , Daly Justine
Published: October 2010

Objectives

Active telephone recruitment (‘cold calling’) can enrol almost 45 times more smokers to cessation services than media. However, the effectiveness of proactive telephone counselling with cold-called smokers from the broader community is unknown. This study examined whether proactive telephone counselling improved abstinence, quit attempts and reduced cigarette consumption among cold-called smokers.

Methods

From 48 014 randomly selected electronic telephone directory numbers, 3008 eligible smokers were identified and 1562 (51.9%) smokers recruited into the randomised controlled trial. Of these, 769 smokers were randomly allocated to proactive telephone counselling and 793 to the control (ie, mailed self-help) conditions. Six counselling calls were offered to intervention smokers willing to quit within a month and four to those not ready to quit. The 4-month, 7-month and 13-month follow-up interviews were completed by 1369 (87.6%), 1278 (81.8%) and 1245 (79.9%) participants, respectively.

Results

Proactive telephone counselling participants were significantly more likely than controls to achieve 7-day point prevalence abstinence at 4 months (13.8% vs 9.6%, p=0.005) and 7 months (14.3% vs 11.0%, p=0.02) but not at 13 months. There was a significant impact of telephone counselling on prolonged abstinence at 4 months (3.4% vs 1.8%, p=0.02) and at 7 months (2.2% vs 0.9%, p=0.02). At 4 months post recruitment, telephone counselling participants were significantly more likely than controls to have made a quit attempt (48.6% vs 42.9%, p=0.01) and reduced cigarette consumption (16.9% vs 9.0%, p=0.0002).

Conclusions

Proactive telephone counselling initially increased abstinence and quitting behaviours among cold-called smokers. Given its superior reach, quitlines should consider active telephone recruitment, provided relapse can be reduced.

Trial registration

Australian New Zealand Clinical Trial Registry; ACTRN012606000221550.
Epidemiological study of pasture‐associated laminitis and concurrent risk factors in the South of England
Authors: Menzies‐Gow N. J. , Katz L. M. , Barker K. J. , Elliott J. , De Brauwere M. N. , Jarvis N. , Marr C. M. , Pfeiffer D. U.
Published: October 2010

A retrospective study of laminitis was carried out to identify risk factors associated with this disease on an East Anglian farm with approximately 1000 animals living in an area of 1000 acres. Medical records between January 1997 and May 2000 and between April 2005 and March 2008 were reviewed, and the age, sex, weight (kg), height (inches [in] and hands [H]) and weight‐to‐height ratio (kg/in) was recorded. The prevalence, incidence and seasonality of laminitis were determined and their relationship to the monthly temperature, rainfall and hours of sunshine was evaluated. Averaged over the six years, the highest prevalence (2.6 per cent) and incidence (16 cases/1000 animals) of laminitis occurred in May. The findings of a multivariate analysis revealed that females (P=0.007, odds ratio [OR] 1.46, 95 per cent confidence interval [CI] 1.1053 to 1.9646) and light animals (P≤0.001, OR=0.995, 95 per cent CI =0.9932 to 0.9963) had the greatest risk of developing laminitis. A positive association was found between hours of sunshine and incidence (P=0.007, relative risk [RR] 1.009, 95 per cent CI 1.001 to 1.012) and prevalence (P=0.002, RR 1.008, 95 per cent CI 1.003 to 1.012) of laminitis. The data suggest that there is a relationship between season, sex of the animal and the development of laminitis.
Use of a tetanus toxoid marker to allow differentiation of infected from vaccinated poultry without affecting the efficacy of a H5N1 avian influenza virus vaccine
Authors: James‐Berry C. M. , Middleton D. , Mansfield J. P. , Fenwick S. G. , Ellis T. M.
Published: October 2010

Tetanus toxoid (TT) was assessed as a positive marker for avian influenza (AI) virus vaccination in chickens, in a vaccination and challenge study. Chickens were vaccinated twice with inactivated AI H5N2 virus vaccine, and then challenged three weeks later with highly pathogenic AI H5N1 virus. Vaccinated chickens were compared with other groups that were either sham‐vaccinated or vaccinated with virus with the TT marker. All sham‐vaccinated chickens died by 36 hours postinfection, whereas all vaccinated chickens, with or without the TT marker, were protected from morbidity and mortality following exposure to the challenge virus. Serological testing for H5‐specific antibodies identified anamnestic responses to H5 in some of the vaccinated birds, indicating active virus infection.
International disease monitoring, July to September
Authors: Roberts H. , Lopez M. , Carbon M. , Hartley M.
Published: October 2010

African swine fever in the Caucasus region

Equine infectious anaemia in several EU member states, including the UK

Foot‐and‐mouth disease in Turkey suggests a problem with vaccination

Outbreaks of West Nile virus in the Mediterranean Basin prompt calls for better collaboration between public health and veterinary authorities in EU member states

These are among matters discussed in the international disease monitoring report for July to September, prepared by Defra's Food and Farming Group, Global Animal Health
Detrital zircon analysis of Mesoproterozoic and Neoproterozoic metasedimentary rocks of north-central Idaho: implications for development of the Belt–Purcell basin
Authors: Lewis Reed S. , Vervoort Jeffrey D. , Burmester Russell F. , Oswald Peter J.
Published: October 2010

The authors analyzed detrital zircon grains from 10 metasedimentary rock samples of the Priest River complex and three other amphibolite-facies metamorphic sequences in north-central Idaho to test the previous assignment of these rocks to the Mesoproterozoic Belt–Purcell Supergroup. Zircon grains from two samples of the Prichard Formation (lower Belt) and one sample of Cambrian quartzite were also analyzed as controls with known depositional ages. U–Pb zircon analysis by laser ablation — inductively coupled plasma — mass spectrometry reveals that 6 of the 10 samples contain multiple age populations between 1900 and 1400 Ma and a scatter of older ages, similar to results reported from the Belt–Purcell Supergroup to the north and east. Results from the Priest River metamorphic complex confirm previous correlations with the Prichard Formation. Samples from the Golden and Elk City sequences have significant numbers of 1500–1380 Ma grains, which indicates that they do not predate the Belt. Rather, they are probably from a relatively young, southwestern part of the Belt Supergroup (Lemhi subbasin). Non-North American (1610–1490 Ma) grains are rare in these rocks. Three samples of quartzite from the Syringa metamorphic sequence northwest of the Idaho batholith contain zircon grains younger than the Belt Supergroup and support a Neoproterozoic age. A single Cambrian sample has abundant 1780 Ma grains and none younger than ∼1750 Ma. These results indicate that the likely protoliths of many high-grade metamorphic rocks in northern Idaho were strata of the Belt–Purcell Supergroup or overlying rocks of the Neoproterozoic Windermere Supergroup and not basement rocks.
Early Devonian stylonurine eurypterids from Arctic Canada
Authors: Lamsdell James C. , Braddy Simon J. , Loeffler Elizabeth J. , Dineley David L.
Published: October 2010

Two new stylonurine eurypterids are described from the Peel Sound Formation (Early Devonian, Lochkovian) of the northern coast of Prince of Wales Island, Nunavut, Arctic Canada. Associations including pteraspids and ostracodes indicate a fluvial depositional environment. An almost complete stylonurid, Pagea plotnicki sp. nov., is recognized by its large size and lack of vaulting on the carapace, and it provides evidence that Stylonurus and Pagea are sister-taxa. Also, a smaller incomplete rhenopterid assigned to Leiopterella tetliei gen. et sp. nov., is characterized by its broad turbinate carapace and lack of cuticular sculpture. This assemblage provides the first Canadian record of Pagea, and the youngest occurrence of a rhenopterid outside the Rheno-Hercynian Terrane, indicating that these taxa were more geographically widespread than previously supposed.
Taphonomy, pathology, and paleoecology of the terminal Pleistocene Marmes Rockshelter (45FR50) “big elk” (Cervus elaphus), southeastern Washington State, USA
Authors: Lyman R. Lee
Published: October 2010

In 1968, remains of what were reported to be a larger-than-modern elk ( Cervus elaphus ) were recovered from terminal Pleistocene sediments associated with the Marmes Rockshelter archaeological site in southeastern Washington State. Originally thought to have been butchered by humans, it is associated with radiocarbon dates suggesting an age of about 980014C years B.P. Taphonomic analysis in 2009 indicates the elk likely died of natural causes during winter months; it was lightly scavenged by carnivores prior to burial from silt-rich spring runoff. The elk suffered from two pathological conditions: one resulting in fusion of the fourth and fifth cervical vertebrae, and the other resulting in excessive bone tissue on the proximal ends of the first ribs, seventh cervical, and first and second thoracic vertebrae. The Marmes elk is larger than modern Rocky Mountain elk ( C. e. nelsoni ) and is on the large end of the size range of modern Roosevelt elk ( C. e. roosevelti ). It is also larger than the similarly aged elk skeleton from Three Hills, Alberta. A single elk bone from the Sentinel Gap archaeological site in central Washington State, dated to about 10 20014C years BP and located 130 km west of Marmes Rockshelter, is the same size as the same bone of the Marmes elk. Terminal Pleistocene elk in eastern Washington likely grew to exceptionally large size as a result of abundant grass at the time, forage that decreased in abundance as Holocene climatic conditions developed.
Revision of the status of Saurolophus (Hadrosauridae) from California, USA
Authors: Bell Phil R. , Evans David C.
Published: October 2010

The occurrence of Saurolophus from the Moreno Formation (late Maastrichtian) of California is investigated and an incomplete, poorly preserved, skull (LACM/CIT 2852) is described. The skull lacks the braincase (including the frontals) and much of the nasals, and the preserved portions are crushed or plastically deformed, which makes anatomical interpretations difficult. A preserved midline fragment of the conjoined nasals suggests that it lacked a gryposaur-like “Roman nose”, but the nature of the crest, if present, is impossible to determine with certainty. A phylogenetic analysis places this specimen as either the sister taxon of Saurolophus or as the sister taxon to a clade comprising Edmontosaurus and Anatotitan . There is no compelling morphological evidence to support the previous assignment of LACM/CIT 2852 to Saurolophus rather than to Edmontosaurus, and its poor preservation prevents positive assignment to any taxon below Hadrosaurinae indet. Given its geographic setting and morphological uncertainties, it is also possible that this specimen represents a separate taxon, but more material is needed to clarify the identity of the Moreno hadrosaurine. LACM/CIT 2852 does, however, provide evidence that Maastrichtian hadrosaurines ranged west of the Sierra Nevada magmatic arc, in an area where dinosaur diversity is poorly known.