bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental comparison of some phenomenological hysteresis models in characterizing hysteresis behavior of shape memory alloy actuators
Authors: Zakerzadeh Mohammad R , Sayyaadi Hassan
Published: June 2012

Among the phenomenological hysteresis models, the Preisach model, Krasnosel’skii–Pokrovskii model, and Prandtl–Ishlinskii model have found extensive applications for modeling hysteresis in shape memory alloys and other smart actuators. Since the mathematical complexity of the identification and inversion problem depends directly on the type of phenomenological hysteresis modeling method, choosing a proper phenomenological model among the mentioned models for modeling the hysteretic behavior of shape memory alloy actuators is a task of crucial importance. Moreover, the accuracy of the hysteresis modeling method in characterizing shape memory alloy hysteretic behavior consequently affects the whole compensator design task. In this article, the accuracy of the mentioned phenomenological models in characterizing and predicting the hysteretic behavior of shape memory alloy actuators is experimentally compared. It will be shown that although, unlike the Preisach and Krasnosel’skii–Pokrovskii models, the identification process of the Prandtl–Ishlinskii model is a time-consuming process, it leads to the best results when the outputs of these models are compared with the experimental data. Since the Prandtl–Ishlinskii model is also analytically invertible and can be easily implemented as a feed-forward controller for compensating the hysteretic nonlinearity behavior of shape memory alloy actuators, it seems to be the best model for modeling and compensating the hysteretic behavior of shape memory alloy actuators.
Non-linear dynamic thermomechanical behaviour of shape memory alloys
Authors: Moussa Mohamed O , Moumni Ziad , Doaré Olivier , Touzé Cyril , Zaki Wael
Published: June 2012

The non-linear dynamic thermomechanical behaviour of superelastic shape memory alloys is investigated. To this end, the Zaki–Moumni model, initially developed for quasi-static loading cases, is extended to simulate the uniaxial forced oscillations of a shape memory alloy device. First, the influence of loading rate is accounted for by considering the thermomechanical coupling in the behaviour of NiTi shape memory alloy. Comparisons between simulations and experimental results show good agreement. Then, the forced response of a shape memory alloy device is investigated at resonance. Both isothermal and non-isothermal conditions are studied, as well as non-symmetric tensile-compressive restoring force. In the case of large values of forcing amplitudes, simulation results show that the dynamic response is prone to jumps, bifurcations and chaotic solutions.
Latino Values in the Context of Palliative Care
Authors: Gaudio F. Del , Hichenberg S. , Eisenberg M. , Kerr E. , Zaider T. I. , Kissane D. W.
Published: June 2012

Background:

Clinicians meet a variety of ethnicities among patients and families in hospice programs. This article focuses on Latino families.

Methods:

Within a controlled trial of family therapy in the context of palliative care, 17 families identified as Hispanic. Five were examined qualitatively herein.

Results:

A synopsis of each family’s narrative is presented here. Patterns of strong family loyalty ( Familismo), the gender roles of Machismo and Marianismo, the importance of family tradition, expectations about caregiving, and the place of faith and religion emerged as prominent and able potentially to impact on the therapy.

Conclusions:

Family therapists need to be thoughtful about cultural issues as they strive to support families.
Active damping of nonstationary vibrations of a rectangular plate under impulse loading
Authors: Kubenko Veniamin D , Yanchevskiy Igor V
Published: June 2012

The behavior of a double-layer (metal-piezoceramics) rectangular plate under nonstationary electromechanical loading is studied. It is assumed that the mechanical load versus time law and the area of its application are specified. The electric signal applied to solid electrode coatings of the piezolayer reduces the amplitudes of mechanically induced vibrations of the plate. Two approaches to determining the profile of the electric signal are considered – the first is focused on minimizing the plate strained state, and the second approach deals with suppressing forced vibrations with an account of minimizing power input for forming a control action. The Kirchhoff-Love generalized hypotheses are used for simulating electromechanical vibrations. The boundary problem solution was derived using the Laplace integral transform in time and separation of variables. To assess the effectiveness of the approaches suggested, the plate vibrations were investigated when the piezolayer was in the direct piezoelectric effect mode. The numerical and analytical results were validated by comparison with finite element solutions. The paper also describes the method of solving the problem of restoring the time dependence of the mechanical load based on known values of the difference of potentials between open piezolayer electrodes, which occur due to bending vibrations of the bimorph plate.
Fuzzy proportional-integral-derivative control of an overhang rotor with double discs based on the active tilting pad journal bearing
Authors: Gong Xiaochun , Cao Dengqing
Published: June 2012

An overhang rotor with two discs supported by a couple of tilting-pad journal bearings is investigated in this paper. The active lubrication based on injecting pressurized oil into the bearing gap through orifices machined in the bearing sliding surface is utilized to suppress the shaft vibrations. A fuzzy proportional-integral-derivative (PID) controller is designed for the active lubrication to adjust the rotor-bearing equilibrium position. The finite difference method is applied to solve the pressure distribution on each tilting pad surface of the active lubricated system. Numerical simulation and experiment results show that the actively lubricated system presents effective vibration reduction of unbalance response of a flexible rotor and the fuzzy PID controller exhibits good performance. Finally the superiorities in employing the active lubricated system with regard to extending the stable operational speed ranges and manage to put off the instabilities (whirl) of the rotor-bearing system are also investigated, and clearly illustrate one of its most promising applications.
Speed-dependent tip fields of a moving crack in a hyperelastic material
Authors: Wu J , Ru CQ
Published: June 2012

This paper gives an asymptotic analysis of plane strain deformation and stress fields near the tip of a steady moving crack in a compressible hyperelastic material. The semi-infinite crack is assumed to be in an infinite homogeneous harmonic material under a constant remote mode-I loading. The crack tip deformation and stress fields are derived up to the third order, which ensures the strict positivity of the Jacobian determinant in the vicinity of the moving crack tip. The derived solutions are applied to a specific hyperelastic material for which some recent experimental data are available in the literature. The comparison with the experimental data showed that the crack-face profile and the energy release rate predicted by the present model are in reasonable agreement with experiments and several recent finite-strain elastic models. In addition, the crack branching angle predicted by the present model also agrees well with some known experimental data. All of these results suggest that the harmonic material model has the potential to capture the main features of finite deformation phenomena in the dynamic fracture of hyperelastic materials.
Non-local elasto-viscoplastic models with dislocations in finite elasto-plasticity. Part II: Influence of dislocations in crystal plasticity
Authors: Cleja-Ţigoiu Sanda , Paşcan Raisa
Published: June 2012

We emphasize the consequences that follow from the constitutive framework of second-order finite elasto-plasticity, with tensorial and scalar measures of dislocations, developed in Part I of this paper, which was restricted to the multislip flow rule for plastic distortion, specifically used in crystal plasticity. The micro-balance equation proposed by Gurtin is obtained. The non-local evolution equations for the plastic shear and scalar dislocation density are built into the appropriate slip system and are compatible with the reduced dissipation inequality. The activation condition is dependent on Noll’s dislocation density tensor, or on the curl of the plastic distortion, and there is a force-like coupling term containing the gradient of the scalar dislocation density, which also produces internal power in conjunction with the rate of plastic distortion. The evolution equation for the scalar dislocation density is non-local and is expressed as a diffusion equation. To study the influence of the non-local description of the scalar dislocation densities on the elasto-plastic behaviour, we consider as an example a layer of an elasto-plastic material when a single slip system could be activated, in a simple shear stress-controlled problem, within a simplified non-local viscoplastic model. For a hardening material, a drastically non-smooth change in the plastic shear and the components of the deformation gradient is emphasized.
A general method to determine the stress intensity factor of multiple collinear cracks
Authors: Jin Wencheng , Zhu Zheming , Gao Mingzhong
Published: June 2012

In this study, the issue of multiple collinear cracks in a finite plate is studied, and the overall stress field as well as stress intensity factors (SIFs) near crack tips are determined. Based on Muskelishvili’s results, the problem is formulated using complex functions in terms of unknown coefficients, which are obtained by enforcing the external boundaries using a least-square boundary collocation method. These functions satisfy all the required conditions, and can be used to calculate the overall stress field, displacement field and the SIFs at the crack tips. Examples of a rectangular plate with one, two and three cracks, respectively, have been calculated, and a set of photoelastic experiments were performed and the results are supportive. At the end, the effect of confining stress, friction coefficient, crack orientation and the distance between crack tips on SIF are investigated.
Axisymmetric thermo-elasticity field in a functionally graded circular plate of transversely isotropic material
Authors: Li Xiang-Yu , Li Pei-Dong , Kang Guo-Zheng , Pan Dong-Zi
Published: June 2012

This paper presents a set of axisymmetric analytical solutions of the thermo-elasticity field induced by the external thermal load, in a heterogeneous circular plate. The plate can be either simply supported or clamped, and the properties of the transversely isotropic material are assumed to be functions of the thickness coordinate. Three typical types of thermal boundary conditions are considered and the corresponding temperature fields are determined. A direct displacement method is used to solve the governing equations for the elastic field in plate. The displacement functions pertinent to the current problem are solved by a step-by-step procedure of integration. The corresponding integral constants are determined by using the cylindrical boundary conditions in the Saint-Venant’s sense. In the present solutions, all of the material coefficients can vary independently and continuously along the thickness direction. Numerical calculations are performed to validate the present solutions and to show their applications to a heterogeneous model. The influence of the material heterogeneity is finally addressed. Since no ad hoc hypotheses on the elastic deformations of the plate are introduced, the present solution can be a nature benchmark to various plate theories and numerical codes.
Task Dissociation in Prospective Memory Performance in Individuals With ADHD
Authors: Altgassen Mareike , Kretschmer Anett , Kliegel Matthias
Published: June 2012

Objective: The present study investigated, for the first time, event- and time-based prospective memory (PM) in the same sample of adults with ADHD within one paradigm using parallel task constraints. Method: A total of 25 individuals with ADHD and 25 matched neurotypical controls completed a computerized version of the Dresden Breakfast Task, which required participants to prepare breakfast following a set of rules and time restrictions. Results: Although groups did not differ in event-based PM, results demonstrated a large-sized impairment in individuals with ADHD in time-based PM. Conclusion: Findings suggest a task-specific impairment in PM functioning and are discussed in an executive control framework of neurocognitive functioning in ADHD.
Latent Inhibition in ADHD Adults On and Off Medication
Authors: Lubow R. E. , Kaplan Oren , Manor Iris
Published: June 2012

Objective: To determine the effects of stimulant medication on performance of ADHD adults on a selective attention task that assesses the processing of irrelevant stimuli. Method: ADHD patients and matched controls were given two sessions of a two-stage visual search-latent inhibition (LI) task. In stage-1, they detected the location of a unique shape presented with homogeneous distractors. In stage- 2, target detection response time was examined as a function of the stage-1 experience with the target or distractor, or both, providing a within-subject measure of LI. In Session-1, the ADHD subjects were off their customary stimulant medication. In Session-2, they were on medication. Results: Off-medicated ADHD subjects exhibited similar LI to that of controls; medicated ADHD subjects exhibited less LI than controls. Group differences in LI were mediated by RTs to the previously task-irrelevant distractor stimulus. Conclusion: The attenuated LI of the on-medication ADHD group is attributable to drug action that reduces attentional resources allocated to distractors.
Reduced Neural Error Signaling in Left Inferior Prefrontal Cortex in Young Adults With ADHD
Authors: Vasic Nenad , Plichta Michael M. , Wolf Robert C. , Fallgatter Andreas J. , Sosic-Vasic Zrinka , Grön Georg
Published: June 2012

Objective: The neural network involved in inhibition of inappropriate response tendencies shares commonalities with the error-processing network, signaling failure of inhibition. Most studies on error processing in ADHD have been conducted in children using electrophysiological methods. Method: Using event-related functional magnetic resonance imaging, the authors studied 14 adults with ADHD and 12 group-matched healthy control participants while performing a modified version of a combined Eriksen Flanker-Go/NoGo-task. Results: Patients with ADHD demonstrated significantly reduced error signaling in the left inferior frontal gyrus bordering the anterior insular cortex (BA 47), computed from the contrast of unsuccessful minus successful inhibition trials. Conclusion: Hypoactivation of the left inferior frontal cortex during error signaling might represent a neurofunctional marker of a crucial prerequisite for error processing in adults with ADHD. This possibly indicates a dysfunction of the neural system that operates task-set related representations and monitoring of erroneous performances in service of ensuing posterror processing.
Probable lumbar acute non-compressive nucleus pulposus extrusion in a cat with acute onset paraparesis
Authors: Chow Keshuan , Beatty Julia A , Voss Katja , Barrs Vanessa R
Published: June 2012

A spinal cord lesion localised caudal to the L6 spinal segment was diagnosed in a 2-year-old female spayed domestic longhair cat with acute onset paraparesis. Magnetic resonance imaging findings were consistent with an acute, non-compressive nucleus pulposus extrusion of the L5–L6 intervertebral disc. The cat was successfully managed with supportive care, including cage confinement.
A survey of southeastern United States veterinarians’ preferences for managing cats with diabetes mellitus
Authors: Smith Jo R , Vrono Zak , Rapoport Gregg S , Turek Michelle M , Creevy Kate E
Published: June 2012

This study evaluated primary practitioners’ perceptions of managing feline diabetics. Surveys distributed during local continuing education events achieved a response rate of 46% (90/195). A mean of 74% feline diabetics required chronic insulin; 26% were transient diabetics. Choice of insulin was most influenced by duration of action: human recombinant protamine zinc insulin was ranked first (42%) and glargine second (27%). Dietary management was always/usually recommended by 97% respondents, with prescription or proprietary low-carbohydrate, high-protein diets recommended in 93% responses. More recent graduates ( P = 0.0419), those who worked in larger practices ( P = 0.0315), and those who saw more transient diabetics ( P = 0.0288) were more likely to recommend dietary change. In-house blood glucose curves (BGCs) were the most popular method of assessing glycemic control, while at-home BGCs were least popular, although their use correlated positively with annual diabetic caseload (r = 0.43, P = 0.0239). Owners mishandling insulin was cited as the most common cause of poor glycemic control, while clinical signs of acromegaly were rarely recognized.
The impact of non-linear stretching on the dynamic stability of a uniformly loaded, thin, warped, rotating, circular disk
Authors: Warner Grant M
Published: June 2012

This article analyzes the dynamic stability of pre-warped, rotating circular disks. Simulation is used to determine asymmetric equilibria and corresponding stability maps for varying load and disk rotation. Experimental results corroborated the presence of a rotating, asymmetric equilibrium for low speeds. At higher speeds, aerodynamically excited vibration made it impossible to identify steady equilibria. However, the nature of the aerodynamic excitation and its onset were dramatically affected by the presence of uniform loading on the disk. In addition, at high rotation speeds, the disk appears to have a steady equilibrium rotation at one quarter of the rotation speed of the disk.
Application of artificial neural networks to the evaluation of the ultimate strength of uniaxially compressed welded stiffened aluminium plates
Authors: Zareei Mohammad Reza , Khedmati Mohammad Reza , Rigo Philippe
Published: June 2012

A series of elastoplastic large-deflection finite element analyses is performed on stiffened aluminium plates with flat-bar stiffeners under in-plane longitudinal compression loads. Then, the closed-form ultimate compressive strength formula is derived for stiffened aluminium plates by regression analysis. Finally, artificial neural network methodology is applied to predict the ultimate strength of uniaxially compressed stiffened aluminium plates. It is found that artificial neural network models can produce a more accurate prediction of the ultimate strength of the stiffened aluminium plates than can the existing empirical formula.
A mechanical model for deepwater steel catenary riser transfer process during installation
Authors: Duan Menglan , Chen Jinghao , Tian Kai , Zhang Jian
Published: June 2012

Steel catenary risers are widely used in the development of marine oil and gas. Deepwater installation is an important procedure that will affect the service life of steel catenary risers. A comprehensive study of a mechanical model for the deepwater steel catenary riser transfer process during installation is performed in this paper. This model is derived on the basis of large deformation beam theory, the catenary method and the Winkler foundation model. Numerical analysis is also undertaken to investigate the factors influencing the transfer process of deepwater steel catenary risers during installation. The model presented is able to complete the transfer process through controlling the length of the cables from the installation vessel and the platform. The procedure can be applied to the design of deepwater steel catenary riser installations.
Preparation and characterization of thermal-responsive non-woven poly (propylene) materials grafted with N-isopropylacrylamide/ β-cyclodextrin
Authors: Amiri Setareh , Zadhoush Ali , Mallakpour Shadpour , Larsen Kim Lambertsen , Duroux Laurent
Published: June 2012

A temperature-sensitive hydrogel was successfully grafted on the surface of non-woven poly(propylene) materials. This was carried out by the application of unmodified β-cyclodextrin and N-isopropylacrylamide monomer in order to develop new functional hydrogels for textile science and technology. Graft polymerization technique was used to graft this temperature-sensitive hydrogel on the surface of plasma-treated non-woven poly(propylene) materials. Fourier transform infrared attenuated total reflection, scanning electron microscopy and elemental analyses confirmed the presence of poly( N-isopropylacrylamide) and β-cyclodextrin components on the surface of the textile. Unmodified β-cyclodextrin content was estimated by the use of elemental analysis to be 97 µg/cm2. The water uptake measurements and differential scanning calorimetry analyses showed that the hydrogel maintained its temperature-sensitive property with a lower critical solution temperature (33.23℃) compared to a non-grafted hydrogel. The wicking time and contact angle measurements showed an improvement of the wicking ability and hydrophilicity of modified non-woven poly(propylene) materials. This investigation facilitates the preparation of smart textiles which possess the temperature-sensitive property of poly( N-isopropylacrylamide) and the ability of inclusion complex formation with guest molecules due to the presence of unmodified β-cyclodextrin in the hydrogel network.
Identity Matters
Authors: Collins Joshua C.
Published: June 2012

Conversations about leadership that primarily consider dominant identity groups (e.g., White people, heterosexuals, men, the able-bodied, etc.) may be less productive than those that think about leadership from the perspective of the diverse groups of people that make up our workforces. HRD’s history is gendered and has demonstrated reluctance to discuss topics critically oriented toward individuals with minority-status identities. Presently lesbian, gay, and bisexual (LGB) identity has not been addressed in the HRD leadership literature. Utilizing prior HRD leadership literature synthesized via an integrative literature review method, a popular ally development model, and six strategies for being critical in HRD, the purpose of this article is to synthesize an LGB-inclusive definition of leadership in HRD.
Paul Davidoff and Planning Education
Authors: Rao Matthew V.
Published: June 2012

While he is often remembered as a tireless advocate, few modern planners remember Paul Davidoff as an educator. In the mid-1960s, Hunter College of the City University of New York conducted a nationwide search for the best possible candidate to develop and head the school’s new graduate program in Urban Planning, and they selected Paul Davidoff. The author of “Advocacy and Pluralism in Planning,” who inspired a generation of young planners to represent the disadvantaged, saw himself as a “planner–scholar–professor” who could shape the field by changing the way that planners were taught. This article looks closely at the founding of the planning program at Hunter to explore Paul Davidoff’s relationship to and interest in the field of planning education, as well as his ability to use this program to implement his educational ideals.
A network-centric terrain database regeneration architecture
Authors: Graniela Benito , Proctor Michael D
Published: June 2012

A great deal has changed since 1997 when Schiavone first described the generic pipeline generation process for building an environmental database for military models and simulations. Environment representations have gone from cartoonist graphics to near real-life renderings possessing properties of physics and intelligence where appropriate. Within this article we discuss several contemporary and past terrain database generation processes, as well as challenges faced in generating terrain databases for military models and simulations today. These challenges include decentralized, distributed modification, frequent and incremental updates, and the need for a shared level of validity by users with heterogeneous needs. We propose a novel approach that addresses network-centric terrain database generation and provides distributed bi-directional, incremental updates that addresses many of these needs. We also developed, tested, and analyzed a prototype architecture and two types of feature modification applied to terrain within the network, the results of which are presented, along with conclusions and future research recommendations.
A particle-filter information potential method for tracking and monitoring maneuvering targets using a mobile sensor agent
Authors: Lu W , Zhang G , Ferrari S , Anderson M , Fierro R
Published: June 2012

The problem of tracking and monitoring moving targets using mobile sensor agents (MSAs) is relevant to a variety of applications, including monitoring of endangered species, civilian security, and military surveillance. This paper presents a new information potential field approach for computing the motion plans and control inputs of a MSA, based on the feedback obtained from a modified particle filter used for tracking multiple moving targets in a region of interest. A modified particle filter is presented that implements a new sampling method based on supporting intervals of normal probability density functions. The method accounts for the latest sensor measurements by adapting a mixture representation of the target probability density functions (PDFs). The target motion is modeled as a semi-Markov jump process, such that the target PDFs, or the PDFs of the Markov parameters, can be updated based on real-time sensor measurements by a centralized processing unit or MSAs supervisor. A new information potential method is presented that computes an artificial potential function based on the output of the modified particle filter. Using this artificial potential, the sensors compute feedback control inputs that allow them to track and monitor a maneuvering target over time, using a bounded field of view (FOV).
Meeting the mental health needs of people with chronic obstructive pulmonary disease: a qualitative study
Authors: Ellison Louise , Gask Linda , Bakerly Nawar Diar , Roberts June
Published: June 2012

Objectives: This study aimed to understand the mental health needs of people living with chronic obstructive pulmonary disease: what they were experiencing, what they wanted (or did not want) which might be described as ‘felt need’, what they had accessed or received (‘expressed need’) and how, from their perspective, their emotional needs might be more effectively met by health care services.

Methods: Qualitative study with 14 patients with a confirmed diagnosis of chronic obstructive pulmonary disease, where a member of the clinical team had recognised that the patient was suffering from associated emotional distress.

Results: Three themes emerged: a sense of assuming a different identity as the disease challenged abilities, the experience of social isolation with fear of dependence and barriers the participants encountered acting as obstacles to coping, adapting and accessing treatments. There were mixed feelings about the value of talking about problems, with both psychological and physical barriers strongly militating against both expression of need and utilization of care offered.

Conclusions: Innovative research and clinical care should be aimed towards development of skills, strategies and systems required to engage sensitively and negotiate needs for care, in a patient-centred manner, with people who do not necessarily see the need to ask for emotional support.
Experiences of young women living with developmental dysplasia of the hip: insight into their experiences of surgery and recovery
Authors: Gambling Tina S , Long Andrew F
Published: June 2012

Objective: To explore the experiences of young women with developmental dysplasia of the hip explicating the impact of peri-acetabular osteotomy surgery and recovery in the short and longer term.

Design: Postings of five, selected women on an online active message board aimed at women with developmental dysplasia of the hip were analysed. Interest lay on their postings after they had had peri-acetabular osteotomy surgery. Data analysis was performed through the approach of interpretive phenomenological analysis.

Results: The time length of the postings for the cases ranged from 1 year to 6 years, and the number of postings varied substantially, from 48 to 591. Two major concepts were prominent across participants’ accounts. The first concept, ‘body image’, centred on affects on the women’s self-esteem and body image. The second, ‘the long road to recovery’, highlighted ‘the emotional and physical battle of learning to walk’ and concerns with ‘saving my joints’.

Conclusion: Developmental dysplasia of the hip potentially provides a critical case for exploration of the process of how a disability can affect confidence, self-esteem and body image. Recovery from this condition requires enormous effort, resilience and commitment from the women.
Coping with chronic complex regional pain syndrome: advice from patients for patients
Authors: Rodham Karen , McCabe Candida , Pilkington Melissa , Regan Laurence
Published: June 2012

Objective: To explore what advice people currently living with chronic complex regional pain syndrome would offer to another person coming to terms with a diagnosis of chronic complex regional pain syndrome.

Methods: Semi-structured interviews with 21 adults (5 male) living with chronic complex regional pain syndrome who had completed a complex regional pain syndrome rehabilitation programme were conducted.

Results: Effectively self-managing complex regional pain syndrome required individuals to play an active role. This could only be achieved if they felt they had sufficient control. Means of attaining control involved attaining a level of acceptance, becoming well-informed and accessing the right kind of support. The advice offered by patients for patients largely reflected that offered by healthcare professionals. One area where there was a conflict concerned sleep hygiene.

Conclusions: Our study provides support both for the argument put forward by Redman that without appropriate preparation and support, self-management is ineffective, and that by Skuladottir and Hallsdottir that the main challenge of the chronic pain trajectory is that of retaining a sense of control. The clinical implications of this are discussed.
The perceived impact of advanced practice nurses (APNs) on promoting evidence-based practice amongst frontline nurses: findings from a collective case study
Authors: McDonnell Ann , Gerrish Kate , Kirshbaum Marilynne N. , Nolan Mike , Tod Angela , Guillaume Louise
Published: June 2012

The aim of this study was to explore the perceived impact of advanced practice nurses in promoting evidence-based practice amongst frontline nurses. A collective instrumental case study was undertaken involving five extended case studies and eighteen short case studies in a range of hospital and primary care settings across seven Strategic Health Authorities in England. The study participants were a purposive sample of 23 advanced practice nurses selected to represent a range of settings, clinical specialities, organisational responsibilities and ways of working. In-depth interviews were undertaken with the advanced practice nurse and up to 10 interviews with health care professionals with whom they worked. For the extended case studies, non-participant observation and follow-up interviews were also undertaken. Data analysis drew on the principles of the Framework approach.

From the perspectives of the participants, these advanced practice nurses enhanced the ability of frontline nurses to provide evidence-based care. They improved the competence, knowledge and skills of frontline nurses and empowered them to deliver care which they considered to be safer, holistic, more timely and of a higher standard. This is likely to have a positive effect on patient outcomes and on patient experience. However, this impact is inherently hard to capture.
High-speed video analysis of arrow behaviour during the power stroke of a recurve archery bow
Authors: Park James L , Logan Oliver
Published: June 2012

The manner in which an archer holds and releases the string of a recurve bow causes the arrow to flex during the bow’s power stroke and on its way from the bow to the target. While an experienced observer can subjectively evaluate an arrow’s pitch and yaw visually after it has left the bow, the arrow’s behaviour during the bow’s power stroke happens too quickly for visual observation. High-speed video is consequently a much more effective tool. Similarly, high-speed video is an effective tool for studying an archer’s technique during the bow’s power stroke.

Mathematical models of the arrow’s behaviour in the horizontal plane during the bow’s power stroke have, to date, relied upon comparison of the arrow’s flexural shape with photographs. However, an implicit assumption of that process is that the archer’s technique is perfect. This paper provides an analysis of event times and the magnitudes of several key components of the arrow flex during the bow’s power stroke for sixteen world-class archers. Aside from being a powerful analysis tool in its own right, that data can also be used to evaluate mathematical models of arrow behaviour. It is concluded that archer technique variations could be a significant source of error where a single archer is used as a comparison for the mathematics, even if that single archer is amongst the world’s best.
Scripting Employees
Authors: Victorino Liana , Bolinger Alexander R.
Published: June 2012

Because customers can recognize when hospitality firms are employing service scripts, an examination is in order to determine how customers perceive scripted service. This article assesses customer perceptions of scripted service encounters with both content analysis and quantitative analysis of more than 2,000 open-ended customer responses to a survey addressing service scripts. The study found both task- and treatment-related implications for customer reactions to scripted service. Customers’ overall sentiment toward scripting is more positive when they are focusing on task-related outcomes, but their comments turned more negative when they considered treatment-related implications, particularly when they detected employee insincerity in regard to the script. Management should consider these findings carefully because customers in this survey gave more notice to treatment-related issues than they did to task-related outcomes for the scripted service. A key implication is that managers may wish to reserve tight scripting for simple services for which efficiency is valued, such as hotel check-in or seating guests in a restaurant. For more complex services, scripts should be flexible, and managers should seek employee buy-in so that they are internalizing the script elements, rather than merely “surface acting.”
Prenatal Diagnosis of VACTERL Association
Authors: Guthrie Joy D. , DeCosta Lindsay
Published: June 2012

VACTERL syndrome is a multisystem congenital anomaly. The potential findings include vertebral, anorectal, and cardiac anomalies; tracheoesophageal fistula/esophageal atresia; and renal and limb anomalies. This case report presents a pregnant woman in her early 30s presenting with multiple fetal anomalies suggesting this diagnosis.
Exencephaly With Ectopia Cordis
Authors: Gibbs Tim S. , Bass Jacqueline , Andrew Melanie
Published: June 2012

Ectopia cordis is an anomaly of embryonic cell growth that causes the heart to form outside the chest cavity during fetal development. Other birth defects are often present with ectopia cordis as well. It is usually a fatal condition, commonly associated with pentalogy of Cantrell, and occurs in 5.5 to 7.9 children per one million live births. Exencephaly is the exposure of a well-developed and differentiated brain outside the skull during the embryonic period. It is the second of three phases in the development of anencephaly and is a lethal neural tube defect with only a small number of cases reported in the literature. Sonographically, it appears as a bilobed-shaped head termed the “Mickey Mouse” head with a relatively large amount of brain tissue present floating in the amniotic fluid.
Intrauterine Myocardial Infarction in a Twin Gestation Complicated by Twin-to-Twin Transfusion Syndrome
Authors: Boyd Roberta (Bobbie) , Kailin Joshua , Allen Raymond J. , Samai Cyrus , Ketchum Diana , Border William L.
Published: June 2012

Twin-to-twin transfusion syndrome (TTTS) is a known complication of 10% to 15% of monochorionic/diamniotic twin gestations. It is also known that the “recipient” twin in these pregnancies is at higher risk for cardiac abnormalities. Early identification of TTTS and recognition of changes in fetal cardiac function can reduce fetal morbidity and mortality. This case describes intrauterine myocardial infarction developing in the recipient twin of a monochorionic/diamniotic twin gestation complicated by TTTS.
Immunoregulation through extracellular nucleotides
Authors: Vitiello Laura , Gorini Stefania , Rosano Giuseppe , la Sala Andrea
Published: June 2012

Extracellular ATP (eATP), the most abundant among nucleotides, can act as a mediator during inflammatory responses by binding to plasmamembrane P2 purinergic receptors, which are widely expressed on cells of the immune system. eATP is generally considered as a classical danger signal, which stimulates immune responses in the presence of tissue damage. Converging evidence from several studies using murine models of chronic inflammation have supported this hypothesis; however, the role of eATP in the regulation of human immune function appears to be more complex. Chronic stimulation with micromolar eATP concentrations inhibits the proliferation of T and NK lymphocytes and enhances the capacity of dendritic cells to promote tolerance. The effect of eATP depends on multiple factors, such as the extent of stimulation, eATP concentration, presence/absence of other mediators in the microenvironment, and pattern of P2 receptor engagement. Small but significant differences in the pattern of P2 receptor expression in mice and humans confer the diverse capacities of ATP in regulating the immune response. Such diversity, which is often overlooked, should therefore be carefully considered when evaluating the role of eATP in human inflammatory and autoimmune diseases.
Impaired natural killer cell self-education and “missing-self” responses in Ly49-deficient mice
Authors: Bélanger Simon , Tu Megan M. , Rahim Mir Munir Ahmed , Mahmoud Ahmad B. , Patel Rajen , Tai Lee-Hwa , Troke Angela D. , Wilhelm Brian T. , Landry Josette-Renée , Zhu Qinzhang , Tung Kenneth S. , Raulet David H. , Makrigiannis Andrew P.
Published: June 2012

Ly49-mediated recognition of MHC-I molecules on host cells is considered vital for natural killer (NK)–cell regulation and education; however, gene-deficient animal models are lacking because of the difficulty in deleting this large multigene family. Here, we describe NK gene complex knockdown (NKCKD) mice that lack expression of Ly49 and related MHC-I receptors on most NK cells. NKCKD NK cells exhibit defective killing of MHC-I–deficient, but otherwise normal, target cells, resulting in defective rejection by NKCKD mice of transplants from various types of MHC-I–deficient mice. Self–MHC-I immunosurveillance by NK cells in NKCKD mice can be rescued by self–MHC-I–specific Ly49 transgenes. Although NKCKD mice display defective recognition of MHC-I–deficient tumor cells, resulting in decreased in vivo tumor cell clearance, NKG2D- or antibody-dependent cell-mediated cytotoxicity–induced tumor cell cytotoxicity and cytokine production induced by activation receptors was efficient in Ly49-deficient NK cells, suggesting MHC-I education of NK cells is a single facet regulating their total potential. These results provide direct genetic evidence that Ly49 expression is necessary for NK-cell education to self–MHC-I molecules and that the absence of these receptors leads to loss of MHC-I–dependent “missing-self” immunosurveillance by NK cells.
Expression of CD30 in patients with acute graft-versus-host disease
Authors: Chen Yi-Bin , McDonough Sean , Hasserjian Robert , Chen Heidi , Coughlin Erin , Illiano Christina , Park In Sun , Jagasia Madan , Spitzer Thomas R. , Cutler Corey S. , Soiffer Robert J. , Ritz Jerome
Published: June 2012

Acute GVHD (aGVHD) remains a major source of morbidity after allogeneic hematopoietic cell transplantation. CD30 is a cell-surface protein expressed on certain activated T cells. We analyzed CD30 expression on peripheral blood T-cell subsets and soluble CD30 levels in 26 patients at the time of presentation of aGVHD, before the initiation of treatment, compared with 27 patients after hematopoietic cell transplantation without aGVHD (NONE). Analysis by flow cytometry showed that patients with aGVHD had a greater percentage of CD30 expressing CD8+ T cells with the difference especially pronounced in the central memory subset (CD8+CD45RO+CD62L+): GVHD median 12.4% (range, 0.8%-33.4%) versus NONE 2.1% (0.7%, 17.5%), P < .001. There were similar levels of CD30 expression in naive T cells, CD4+ T cells, and regulatory (CD4+CD127lowCD25+) T cells. Plasma levels of soluble CD30 were significantly greater in patients with GVHD: median 61.7 ng/mL (range, 9.8-357.1 ng/mL) versus 17.4 (range, 3.7-142.4 ng/mL) in NONE (P < .001). Immunohistochemical analysis of affected intestinal tissue showed many CD30+ infiltrating lymphocytes present. These results suggest that CD30 expression on CD8+ T-cell subsets or plasma levels of soluble CD30 may be a potential biomarker for aGVHD. CD30 may also represent a target for novel therapeutic approaches for aGVHD.
Tissue factor promotes activation of coagulation and inflammation in a mouse model of sickle cell disease
Authors: Chantrathammachart Pichika , Mackman Nigel , Sparkenbaugh Erica , Wang Jian-Guo , Parise Leslie V. , Kirchhofer Daniel , Key Nigel S. , Pawlinski Rafal
Published: June 2012

Sickle cell disease (SCD) is associated with a complex vascular pathophysiology that includes activation of coagulation and inflammation. However, the crosstalk between these 2 systems in SCD has not been investigated. Here, we examined the role of tissue factor (TF) in the activation of coagulation and inflammation in 2 different mouse models of SCD (BERK and Townes). Leukocytes isolated from BERK mice expressed TF protein and had increased TF activity compared with control mice. We found that an inhibitory anti-TF antibody abrogated the activation of coagulation but had no effect on hemolysis or anemia. Importantly, inhibition of TF also attenuated inflammation and endothelial cell injury as demonstrated by reduced plasma levels of IL-6, serum amyloid P, and soluble vascular cell adhesion molecule-1. In addition, we found decreased levels of the chemokines MCP-1 and KC, as well as myeloperoxidase in the lungs of sickle cell mice treated with the anti-TF antibody. Finally, we found that endothelial cell-specific deletion of TF had no effect on coagulation but selectively attenuated plasma levels of IL-6. Our data indicate that different cellular sources of TF contribute to activation of coagulation, vascular inflammation, and endothelial cell injury. Furthermore, it appears that TF contributes to these processes without affecting intravascular hemolysis.
Phytoestrogen Genistein Up-Regulates Endothelial Nitric Oxide Synthase Expression Via Activation of cAMP Response Element-Binding Protein in Human Aortic Endothelial Cells
Authors: Si Hongwei , Yu Jie , Jiang Hongling , Lum Hazel , Liu Dongmin
Published: June 2012

We previously reported that genistein, a phytoestrogen, up-regulates endothelial nitric oxide synthase (eNOS) and prevents hypertension in rats that are independent of estrogen signaling machinery. However, how genistein regulates eNOS expression is unknown. In the present study, we show that genistein enhanced eNOS expression and NO synthesis in primary human aortic endothelial cells. Inhibition of extracellular signal regulated kinase, phosphoinositol-3 kinase, or protein kinase C did not affect genistein-enhanced eNOS expression and NO synthesis. However, chemical inhibition of protein kinase A (PKA) or adenoviral transfer of the specific endogenous PKA inhibitor gene completely abolished PKA activity and genistein-stimulated eNOS expression and NO production. Accordingly, genistein induced PKA activity and subsequent phosphorylation of cAMP response element (CRE)-binding protein (CREB) at Ser133. Suppression of CREB by small interfering RNA transfection abolished genistein-enhanced eNOS expression and NO production. Consistently, deletion of the CRE site within human eNOS promoter eliminated genistein-stimulated eNOS promoter activity. These findings provide the first evidence to our knowledge that genistein may play a beneficial role in vascular function through targeting the PKA/CREB/eNOS/NO signaling pathway.
Salt marsh sediment and metal fluxes in response to rainfall
Authors: Chen Si , Torres Raymond , Bizimis Michael , Wirth Edward F.
Published: June 2012

Lay Abstract

We hypothesize that rainfall during low tide is an important process that affects the cycling of materials (nutrients and metals) in estuaries. We simulated a 45‐min rainfall event in a salt marsh to examine the effects of a low‐tide summer storm on the sediment surface. Surface runoff (sediment concentration (SC), discharge, and rainfall rate) at the downslope end of a 1‐ ×  2‐m plot was collected and analyzed chemically in the laboratory. SC peaked at 6100 mg L–1 after 3 min and remained elevated for 15 min before declining. The metal content of the sediments varied considerably with time but was consistently higher than the average background content by a factor of 4–4000. Based on these experimental results, we estimated that 4.8–8.4 tonnes of sediment per square kilometer per minute can be entrained by rainfall during low tide, or up to 96–168 tonnes per year. We also estimated the annual loading of heavy metals that occurs in larger subtidal channels fed by intertidal creeks draining the salt marsh in response to rainfall. Our results demonstrate that rainfall‐entrained sediment during low tides is an important process affecting the cycling of materials in estuarine ecosystems.
Seasonal variation in energy expenditure is not related to activity level or water temperature in a large diving bird
Authors: Guillemette Magella , Butler Patrick
Published: June 2012

There is considerable interest in understanding how the energy budget of an endotherm is modulated from a physiological and ecological point of view. In this paper, we used the heart rate method and daily heart rate (DHR), as a proxy of DEE across seasons, to test the effect of locomotion activity and water temperature on the energy budget of a large diving bird. DHR was monitored continuously in common eiders (Somateria mollissima) during seven months together with measures of time spent flying and time spent feeding. DHR varied substantially during the recording period with numerous increases and decreases that occurred across seasons although we could not find any relationship between DHR and the time spent active (feeding and flying). However, inactive heart rate (IHR) decreased as locomotion activity increases suggesting common eiders were using behavioural compensation when under a high work load. We were also unable to detect a negative relationship between water temperature and resting heart rate, a proxy of resting metabolic rate. This was unexpected based on the assumption that high thermoregulation costs would be associated with cold waters. We showed that high level of energy expenditure coincided with feather moult and warm waters, which suggest that the observed variable pattern of seasonal DEE was driven by feather growth and possibly by other productive costs. Nevertheless, our results indicate that behavioural compensation and possibly the timing of moult may be used as mechanisms to reduce seasonal variation in energy expenditure.