bluuebunny/crossref_metadata_2025 huggingface dataset:
An adverse drug reaction reporting scheme for community pharmacists
Authors: Whittlesea Cate M C , Walker Roger
Published: February 2011

During a 17-month study to determine if community pharmacists have access to sufficient appropriate and relevant information to complete adverse drug reaction reports, 21 out of 98 pharmacies submitted 49 ADR reports. Each report required 31 fields of information. Between 15 and 30 fields were completed on each report. Twelve reports covered “new” medicines (identified in the British National Formulary by a black triangle), 19 “established” medicines, nine generic medicines and nine pharmacy only (P) medicines. Evaluation of the reports by a panel of six pharmacists revealed total agreement that 16 of the reports (33 per cent) were ADRs but one was not. A further 16 (33 per cent) reports were considered by all but one panel member to be ADRs. There was a varying level of agreement over the remaining 17 (35 per cent) reports. Eight months into the study, the participating pharmacists evaluated the scheme by postal questionnaire. The replies indicated that submitting reports to both the Committee on Safety of Medicines (CSM) and the patient's general medical practitioner were the preferred route of 87 per cent and 75 per cent of respondents, respectively, for reporting ADRs to new and established prescription only medicines, while 59 per cent favoured direct submission to the CSM alone for ADRs to medicines purchased over the counter. The results demonstrate that the pharmacist has appropriate knowledge and access to sufficient information to identify and submit ADR reports.
Variability of prescribed daily doses (PDDs) with respect to sex and age in the usage of simvastatin
Authors: Truter I , Van Kotze T J W
Published: February 2011

The variability of the prescribed daily dose (PDD) of simvastatin for different sex and age groups was investigated. Prescription data for 2,336 patients, on various medical schemes, who were using hypolipidaemic drugs on a chronic basis were analysed retrospectively over a one-year period ending on March 27, 1995. Most patients (62.5 per cent) on simvastatin were between 50 and 69 years of age. The average PDD of simvastatin was 12.6mg (12.5mg for females and 12.7mg for males). Average PDDs were in all cases lower than the defined daily dose (DDD) of 15mg, except for females aged 30 to 39 years. In almost all age and sex groups, a dose of 10mg was the median as well as the mode. The standard deviation of the PDD for females and males decreased after the age interval of 40 to 49 years.

Variation exists in the dosage regimen of most drugs, depending on a multitude of factors, such as the severity of the disease state, sex and age. This was also the case with simvastatin for this patient sample.
HEALTH SERVICES RESEARCH METHODS IN PHARMACY: Introduction
Authors: Smith Felicity
Published: February 2011

This article forms the introduction to a series of review articles designed to guide readers on the selection and application of different health service research methodologies in pharmacy practice research. The reviews will discuss different methods that have been used in pharmacy practice settings, their advantages and disadvantages, problems that have arisen and how these have been addressed. The first article, on survey research, follows on p152. Future articles, which will include discussion of semi-structured and qualitative interviews, observation studies, and research into service evaluation, are planned for later issues
The community pharmacist as a member of a primary health care team in South Africa — perceptions of pharmacists, doctors and nurses
Authors: Gilbert Leah
Published: February 2011

The growing emphasis on primary health care (PHC) has drawn increased attention to disease prevention and health promotion activities from many health professionals, among them pharmacists. This paper explores the role of the community pharmacist as a member of the PHC team in South Africa, through the perceptions of pharmacists, nurses and doctors. Data were collected by survey and interviews. The results reveal a scenario where pharmacists are eager to engage in PHC activities, whereas nurses and doctors are more cautious in their support. Although they see pharmacists as health professionals, and are of the opinion that they should play a part in the PHC team, doctors and nurses strongly protect their own domains when it comes to allocation of potential tasks. This raises some difficulties with regard to the effective implementation of PHC. Based on the South African reality and a literature review, suggestions are made to develop models of PHC centres which would potentially overcome some of the problems raised.
Mass media health information available to young adults in the United Kingdom: (2) Television and radio
Authors: Gray Nicola J , Cantrill Judith A , Noyce Peter R
Published: February 2011

In order to examine health information given in television and radio broadcasts popular with young adults (15- to 24-year-olds) in the United Kingdom, three terrestrial television channels and six radio stations were surveyed over eight weeks, using methodology described previously. One hundred and eighty-seven health items were found during 54 hours of television and 58 hours of radio broadcasting. Television commonly included health information within programme storylines and advertisements; radio included advertisements and news items. Descriptions of disease treatment and states were the most common subjects on television, but radio also covered substance misuse and sexual health issues. The central nervous system was the most prevalent therapeutic area. Ninety-two television items (56.8 per cent) and 15 radio items (60.0 per cent) referred to a specific drug or medicine. The drug properties most often described were indication and formulation. Side effects were more likely to be reported on the radio, and hazards were a major issue within items about substance misuse. As with the first part of this study, which reported on health information given in the press (p180), references to contacting any professional sources for further information were rare, and certainly do not lead young consumers to expect to be questioned about the appropriateness of products when subsequently purchasing them. This study challenges community pharmacy to reconsider how it best continues to discharge its consumer protection role in an era of increasing consumer empowerment.
A review of factors that influence the use of community pharmacies as a primary health care resource
Authors: Hassell Karen , Noyce Peter R , Rogers Anne
Published: February 2011

This review paper provides an analysis of a range of pharmacy practice, health services and sociological literature relevant to understanding how the public in the United Kingdom use and view community pharmacies as a primary health care resource. Papers published between 1980 and 1997 inclusive were identified, based on on-line searches of databases, and hand searches of a published literature index, relevant journals, and bibliographies of published papers. Papers included in the review are those which report findings on any aspect of consumers' views and use of community pharmacies. No attempt is made to evaluate the adequacy of the findings since the level of reporting in most short papers does not allow for this type of evaluation. Instead, the review paper “maps out” what is currently known about pharmacy utilisation. Key variables that have been used to explain pharmacy use, including a number of demographic and organisational factors, are identified, as well as factors associated with need and demand issues. The paper summarises the main empirical findings, and provides a view of where further work could add to a greater understanding of the relationship between the delivery of pharmaceutical services and primary health care. Potential strategies that could positively influence consumer demand for community pharmacy services are discussed.
Referrals made by different health care professionals to community pharmacists for domiciliary visits
Authors: Foulsham Russell , Goodyer Larry
Published: February 2011

Objective

To examine the suitability of referrals made by health professionals to a pharmacist for a domiciliary visiting service.

Method

General practitioners (GPs), district nurses and social services carers were contacted to request that they refer patients who they thought might benefit from a home visit by a pharmacist, using a referral form agreed by an expert panel. Information gathered by the visiting pharmacist during the patient interview was compared with the reason for referral by the health care worker.

Setting

All GPs, district nurses and social services carers who cared for housebound patients in the Kenton and Stanmore areas of the London Borough of Harrow.

Key findings

Ninety patients were visited. Of these, 47 had been referred by GPs, 29 by nurses and 14 by social services. The highest level of incorrectly stated referrals (22 per cent of their referrals) came from nurses. Nurses tended to refer patients for an explanation of the purpose of their medicines, and GPs because patients were taking more than three medications. Six patients, five of whom were referred by GPs, appeared not to have any problems that could be helped by a visit.

Conclusion

There may be a need to raise awareness among social services carers about potential medication problems and the role that could be played by community pharmacists in helping these patients. When GPs make referrals, the criterion of patients taking more than three medications may not be sufficiently sensitive; this should be expanded to ensure that the GP has additional clinically related suspicions that there are adherence issues. Generally, little difference was found between the appropriateness of referrals from the three agencies.
Cross-sectoral pharmacotherapeutic coherence in the Netherlands
Authors: Fijn R , Brouwers J R B J , De Van den Berg L T W Jong
Published: February 2011

Objectives

To measure the extent of pharmacotherapeutic coherence across sectors of Dutch health care from the hospitals' perspective, and to identify perceived markers of coherence and barriers to improvement

Methods

Telephone interviews were carried out with hospital pharmacists (76), community pharmacists (5), and clinical pharmacologists (9) affiliated to pharmacies serving 120 Dutch general hospitals. Coherence between (a) hospital and general practice, (b) hospital and nursing home practice, (c) hospitals, and (d) hospital inpatient and outpatient practice was reported and assessed against a set of indicators

Results

Almost all hospitals (93 per cent) had formulary agreements or prescribing policies in place and 86 per cent of these had a printed hospital drug formulary (HDF). Over 50 per cent of hospitals reported that they had established coherence with nursing home practice and/or with other hospitals. Less than half of the hospitals had established coherence with general practice. Few hospitals reported activities to review outpatient prescribing and its implications for follow-on prescribing in primary care. Reported barriers to increasing coherence could be classed into three categories: economic, organisational and social. Suggestions to enhance coherence included influencing professionals' practice through training, and greater use of regional and national policies on prescribing

Conclusion

Therapeutic coherence within Dutch health care is far from ideal. The discrepancy between the actual and desired extent of coherence arises from organisational and economic barriers. To date, activities in this area have relied on professional proactivity rather than a structured approach. To move forward, (dis)incentives should be created for health care providers and professionals across all sectors, including pharmacists and prescribers
Cost-effective prescribing in general practice: Patients' attitudes to financially motivated prescribing changes
Authors: Russell David , Luthra Manjo , Plastow Liz , Airdrie Ruth , Marshall Martin
Published: February 2011

Objectives

To assess the patient acceptability of a personalised letter suggesting a change of repeat medication to a generic or cheaper equivalent brand, to determine the resulting cost savings and to investigate patients' attitudes to cost-effective prescribing.

Method

Patients identified from their records as receiving a predefined group of repeat prescriptions for medication that could be prescribed more cheaply were sent a letter from their own general practitioner asking them to consider changing their prescription. They were given the option to agree to the change, to refuse or to discuss the change with their doctor. Qualitative semi-structured interviews were conducted with a purposeful sample of those who agreed and those who refused the suggested change.

Setting

Two fundholding practices in the south west of England with a combined list size of 15,500.

Key findings

The letter was sent to 323 patients, of whom 252 responded (78 per cent). One hundred and eighty-two patients (72.2 per cent) agreed to the suggested change, 37 (14.7 per cent) refused and 33 (13.1 per cent) wished to discuss the suggestion with their doctor. Eleven of the last group subsequently agreed to change, resulting in a total of 193 (76.6 per cent) agreeing to the change and 59 (23.4 per cent) refusing to change. Four months after the change was made, four patients (2 per cent) had reverted to their previous prescription. The changes resulted in an annual saving to the practice of £10,038 (1.1 per cent of total prescribing budget). The total cost of conducting the changes (including staff time) was £1,800.

Conclusion

Changing repeat medication to equivalent generics or cheaper brands can result in significant cost savings in general practice, and a short personalised letter is an effective and acceptable way of achieving the change.
Clinical decision making — an application of judgment analysis and its potential for pharmacy
Authors: Weiss Marjorie C , Scott David
Published: February 2011

Objectives

To explore the methodological use of judgment analysis in understanding clinical decision-making among United Kingdom(UK) general practitioners (GPs), and to consider how it might be applied to pharmacy.

Method

Written cases, with clinical and social patient information, were developed for sore throat and dyspepsia. Decision models were created relating social and clinical information to: (1) GPs' perceptions of severity (sore throat); (2) the likelihood of an ulcer diagnosis (dyspepsia).

Setting

Two counties in southern England.

Key findings

Of the 47 practices contacted, 17 (36 per cent) participated with 24 general practitioners completing the sore throat series and 24 different GPs completing the dyspepsia series. Twenty GPs (42 per cent) had decision models incorporating social factors. These GPs were no more likely to prescribe on paper or in practice than those with decision models without social factors.

Conclusion

Judgment analysis has yet to be applied to the decision-making of practising pharmacists. Potential applications include pharmacists' decisionmaking in the area of minor ailment management or the decision when to intervene when monitoring prescriptions. The influence of social factors, such as patient demand, social class or a distressing patient circumstance on pharmacists' decision-making are aspects of decision-making particularly worthy of future investigation.
Extended adherence support by community pharmacists for patients with hypertension: a randomised controlled trial
Authors: Blenkinsopp A , Phelan M , Bourne J , Dakhil N
Published: February 2011

Objective

To determine the effects of a patient-centred intervention by community pharmacists on adherence to treatment for hypertension.

Study design

Randomised controlled trial.

Method

Randomisation was at pharmacy level. Pharmacists in the intervention group used a structured, brief questioning protocol to identify patients' medication-related problems and their information needs relating to hypertension and its treatment. Advice, information and referral to the general practitioner (GP) were provided by the pharmacist, based on patients' responses. Pharmacists in the control group provided usual care. The intervention was delivered three times at approximately two-month intervals. Blood pressure measurements were collected retrospectively from GP medical records. Patients completed feedback questionnaires at baseline and post-study. The questionnaire comprised a self-reported adherence measure and explored satisfaction with pharmaceutical services.

Setting

Twenty community pharmacy sites (11 intervention and nine controls) in one health authority area in England.

Outcome measures

Control of blood pressure; patient satisfaction with pharmaceutical services; self-reported adherence.

Results

In total, 180 patients (101 intervention and 79 control) from 43 general medical practices completed the trial. Patients whose blood pressure was uncontrolled prior to the study were more likely to become controlled in the intervention group (P<0.05). Most of the effect on self-reported adherence was seen after the first intervention. Patient satisfaction was high prior to the study and was increased in the intervention group after the study. The increase was statistically significant for five items relating to communication between pharmacist and patient.

Conclusion

A simple intervention delivered by community pharmacists produces positive effects on blood pressure control, self-reported adherence and on patient satisfaction with pharmaceutical services.
Surveys of drug-related therapy problems of patients using medicines for allergy, asthma and pain
Authors: Nilsson J LARS G , Andersson Åsa , Kälvemark Sofia , Lieberman-Ram Helen , Ullenius Birgitta , Wendel Ann , Åberg Åsa
Published: February 2011

Objective

To determine the incidence of drug-related therapy problems (DRTPs) among patients obtaining medicines for allergy, asthma or pain.

Method

Problem detection interventions at the pharmacies were carried out as project-like activities. Pharmacy staff members used open-ended questions to detect all DRTPs in patients presenting prescriptions for medicine for allergy, asthma and pain and in people buying over-the-counter (OTC) medicines for allergy. The data were collected under regular health care conditions and the study can therefore be considered as a survey of the epidemiology of DRTPs among the selected groups of patients.

Setting

Swedish community pharmacies during two one-year nationwide disease management programmes on allergy and pain.

Key findings

Of the 44,504 patients with prescriptions registered in the study, 13,895 (31 per cent) with DRTPs were detected. Of 1,135 people buying OTC medicines for hay fever/pollen allergy, 144 (13 per cent) with DRTPs were detected.

Conclusion

The study indicates that about one-third of patients with prescriptions have DRTPs. Only a fraction of all DRTPs are apparently discovered in the regular dispensing process at the pharmacies. Pharmacy staff need to use more active interventions, such as dialogue with open-ended questions, to efficiently identify and help patients with DRTPs.
Concordance: what is the relevance for pharmacists?
Authors: Stevenson Fiona A
Published: February 2011

Non-adherence (or non-compliance) to prescribed medicines has long been regarded as problematic. The concept of concordance, rather than seeking ways to persuade people to take their medicines, instead focuses on the need to adopt a different model of the patient-prescriber relationship. Much of the discussion about concordance thus far has related to the relationship between doctors and patients. In this article, the role of the pharmacist and ways in which pharmacists could usefully engage with the concordance model, both as part of the primary health care team and as independent practitioners, are considered.

Concordance was developed as an ideal to which to aspire and needs to make the transition into practice. It is however important to note that if the move towards concordance is to happen and be successful it will require the support, enthusiasm and commitment of patients and health care professionals generally.
Does the concordance concept serve patient medication management?
Authors:   PCOPR Investigatne Research Team, Chewning Betty , Boh Larry , Wiederholt Joe , Kreling Dave , van Koningsveld Richard , Wilson Dale , Bell Carolyn , Boh Dawn , Nowlin Nancy , Douglas Jeff
Published: February 2011

Objectives

To assess how people with arthritis evaluate and calibrate their complex medication regimens. Building on these findings, to explore how the concept of concordance helps to describe a patient-provider partnership model which can aid optimum medication regimen selection, calibration and management of chronic conditions.

Method

A longitudinal study of 689 patients diagnosed with osteoarthritis (OA) or rheumatoid arthritis (RA) was conducted to identify patient perceptions, decision-making and behaviour related to their medication management. Face to face interviews with the Brief Medication Questionnaire, health quality of life questionnaires (AIMS2 and SF-36) and telephone interviews were conducted in waves centered around patient visits every six months for two years. Data about medication regimens were abstracted from the clinic medication profile record for each visit.

Setting

Three rheumatology clinics in the United States: a university clinic, a private clinic and a Veterans Administration clinic.

Key findings

About half of the patients in the sample had complex regimens with eight or more medications at any one time. The majority of physicians altered patients' medication orders every six months. The majority of patients reported that they evaluated the effectiveness and side effects of individual medicines based largely on symptoms. There were 248 reported deviations in the scheduled medications at baseline and the majority (61 per cent) were intentional, largely based on symptoms.

Conclusion

Providers and patients each had unique expertise and were engaged in a dynamic process of calibrating patients' ever-changing regimens. In the absence of a perfect static regimen for patients, the concept of concordance productively reflects the partnership and mutual respect needed for ongoing medication regimen selection, calibration and management for a long-term condition.
Satisfaction with information and its relationship with adherence in patients with chronic pain
Authors: Kendrew P , Ward F , Buick D , Wright D , Horne R , Kendrew P , Ward F
Published: February 2011

Focal points
Testing two methods of presenting side effect risk information about common medicines
Authors: Knapp P , Berry D C , Raynor D K
Published: February 2011

Focal points
From compliance to concordance: meeting the needs of patients?
Authors: Bissell Paul , May Carl , Noyce Peter
Published: February 2011

Focal points
Factors influencing community pharmacist participation in clinical audit: a qualitative study of barriers and drivers of change
Authors: Macrae F , Bennie M , Parr R M , Johnson J R
Published: February 2011

Focal points
A comparative study of pharmacist and GP management of anticoagulant therapy following deviation from the target international normalised ratio
Authors: Holden K , Holden J
Published: February 2011

Focal points
Integrating community pharmacy with NHS Direct: evaluation of a pilot scheme
Authors: Munro James , O'Cathain Alicia , Knowles Emma , Nicholl Jon
Published: February 2011

Focal points
The impact of hospital antimicrobial policy on the incidence of Clostridium difficile infection
Authors: Schober A H , McElnay J C , Scott M G , Kearney M P
Published: February 2011

Focal points
Patients' perspectives on medicines and pharmacy: views of patients with Type 2 diabetes
Authors: Douglas E , Chapman S , Hudson S , Paterson K , Duggan C
Published: February 2011

Focal points
Risk assessment of intravenous dose presentation in secondary care
Authors: Joshi K , Graham-Clarke E , Smith J , Langley C A , Marriott J F , Wilson K A
Published: February 2011

Focal points
Action learning as an improved method for continuing professional development for pharmacists providing women's health care advice
Authors: McAree D P , Scott E M
Published: February 2011

Focal points
Changing pharmacists' and pharmacist assistants' practice in dealing with direct requests for non-prescription analgesics
Authors: SIGRIST T , BENRIMOJ S I , HERSBERGER K , LANGFORD J
Published: February 2011

Objectives

To design, implement and evaluate an intervention to improve pharmacists' and pharmacist assistants' practice in dealing with non-prescription analgesics.

Method

Direct request situations, rather than symptom presentation situations, were targeted. A sample of 27 pharmacies (14 intervention, 13 control) was recruited in the French speaking Canton of Neuchâtel, Switzerland. Intervention pharmacies participated in a training programme developed at the University of Sydney based on psycho-social and behavioural conceptual frameworks and communication skills. A pseudo-patient technique was used to assess the effect of training on the frequency and quality of pharmacists' and pharmacist assistants' verbal interaction with their patients. The pseudo-patient visits were followed-up by the provision of immediate feedback to the intervention group, a form of ongoing training. A scoring system was developed for the consultation with the pseudo-patient and 189 interactions were audio-taped and analysed. One-way analysis of variance was used to compare the mean total scores obtained in the intervention and the control groups, at each time point (seven pseudo-patient visits in each pharmacy). The study period was two months.

Key findings

There were significant differences (P<0.05) between the scores obtained in the intervention and control groups. Pharmacists' and pharmacist assistants' practice changed pre- and post-intervention. Interactions involving C-list (pharmacy only) medicines showed a greater change than those involving D-list (not restricted to pharmacies) medicines.

Conclusion

The results indicate that the training programme and the pseudopatient methodology facilitated a more comprehensive questioning process and increased the provision of personalised advice to individual patients.
Pharmacists solving problems in asthma management — experiences from a one-year intervention programme in Finland
Authors: NÄRHI ULLA , AIRAKSINEN MARJA , ENLUND HANNES
Published: February 2011

Objective

To study the effect of an intervention provided by community pharmacists on detection and resolution of problems in asthma patients' self-management and to study patients' opinions about the perceived usefulness of the pharmacists' input.

Method

A one-year intervention study was conducted with scheduled visits and follow-ups at baseline, four, eight and 12 months. Study patients (n=28) acted as their own controls.

Setting

Four communities and community pharmacies in different parts of Finland.

Key findings

At study baseline, all patients had at least one documented problem, the most commonly reported being problems with medication, side effects, problems with inhalation devices and not using asthma medicines according to the physician's instructions. On average, patients had five “intervention” consultations with the pharmacist during the one-year study. After the intervention, half of the patients reported that their problems had been resolved. The most useful areas of advice were considered by the patients to be instructions about changing asthma medication according to asthma symptoms and management of asthma symptoms. Twenty-five of the 28 patients reported that they were satisfied with the education and counselling provided by pharmacists, a higher number than for physicians or nurses.

Conclusion

The findings from this small longitudinal study indicate that community pharmacists can improve asthma patients' treatment by consultations during which they identify and address problems in self-management of asthma.
Pharmaceutical care across different social groups
Authors: Harding J A , McElnay J C
Published: February 2011

Focal points
Use of non-prescription therapies, including complementary medicines, in type 2 diabetes: the Fremantle diabetes study
Authors: Clifford R M , Davis W A , Batty K , Davis T M E
Published: February 2011

Focal points
Pharmacist-led hypertension drug use review
Authors: Braybrook S , Thomas J , Wilkin P S , Haynes W , Jarvis I , Conaty D
Published: February 2011

Focal points
The views of pharmacists supplying emergency hormonal contraception through a patient group direction
Authors: Seston E M , Smith I , Watkins L K
Published: February 2011

Focal points
Does improvement in the benzodiazepine prescribing indicator reflect more appropriate prescribing of hypnotics?
Authors: Kendall H E , Naisbitt S M
Published: February 2011

Focal points
Advice giving in community pharmacies on presentation of NHS prescriptions
Authors: Cooper Stacey , Phul Sharon , Cantrill Judith A
Published: February 2011

Focal points
An analysis of dispensing errors in NHS hospitals
Authors: Roberts D E , Spencer M G , Burfield R , Bowden S
Published: February 2011

Focal points
Preventing drug-related morbidity: determining valid indicators
Authors: Morris C J , Cantrill J A , Avery A J , Howard R L
Published: February 2011

Focal points
Management of gastro-oesophageal reflux in infants
Authors: Azzopardi Lilian M , Inglott Anthony Serracino , Adami Maurice Zarb
Published: February 2011

Focal points
In vivo stimulation of oestrogen receptor α increases insulin‐stimulated skeletal muscle glucose uptake
Authors: Gorres Brittany K. , Bomhoff Gregory L. , Morris Jill K. , Geiger Paige C.
Published: February 2011

Non‐technical summary  Previous studies show that oestrogen is beneficial for maintaining blood glucose levels and helping the body respond to insulin. Despite these previous findings, the mechanism by which oestrogen acts is unknown. We show that specific activation of oestrogen receptor α (ERα) increases glucose uptake into skeletal muscle when insulin is present. Activation of oestrogen receptor β (ERβ) alone or activation of both ERα and ERβ together did not increase glucose uptake into skeletal muscle. This suggests that oestrogen's beneficial effect occurs by activating ERα. These results have important implications for understanding the mechanisms of glucose homeostasis, particularly in postmenopausal women with low oestrogen levels.
Oral atorvastatin therapy restores cutaneous microvascular function by decreasing arginase activity in hypercholesterolaemic humans
Authors: Holowatz Lacy A. , Santhanam Lakshmi , Webb Alanah , Berkowitz Dan E. , Kenney W. Larry
Published: February 2011

Non‐technical summary  A high concentration of cholesterol in the blood, known as hypercholersterolaemia, in the absence of overt atherosclerotic disease induces changes throughout the circulation including an inability to fully respond to vasodilatory stimuli. Here we show that skin blood flow responses are reduced in hypercholersterolaemic men and women partly due to an upregulation of the arginase pathway. Arginase competes for the common substrate l‐arginine for the synthesis of the vasoprotective molecule nitric oxide. After 3 months of oral atrovastatin (cholesterol lowering medication) intervention, arginase activity was decreased and skin blood flow responses resembled those of healthy men and women. This suggests that upregulated arginase contributes to decreased vasoreactivity in hyperocholesterolaemic humans and that atrovastatin therapy restores functional vasodilatory properties by decreasing arginase activity.
Zn

0.6

Fe

0.1

Cu

0.3

/
GDC

Composite Anode for Solid Oxide Fuel Cell
Authors: Raza Rizwan , Zhu Bin , Fransson Torsten H.
Published: February 2011

Recent research results show that homogeneity and microstructure are very important parameters for the development of low cost materials with better performance for fuel cell applications. This research effort has been contributed in the development of low temperature solid oxide fuel cell (LTSOFC) material and technology as well as applications for polygeneration. The microstructure and electrochemical analyses were conducted. We found a series of new electrode materials which can run solid oxide fuel cell at 300–600°C range with high performances, e.g., a high power density output of 980 mW cm−2 was obtained at 570°C. The fuel cell electrodes were prepared from metal oxide materials through a solid state reaction and then mixed with doped ceria. The obtained results have many advantages for the development of LTSOFCs for polygeneration. The nanostructure of the anode has been studied by high-resolution electron microscopy, the crystal structure and lattice parameters have also been studied by X-ray diffraction. The electrical conductivity of the composite anode was studied by electrochemical impedance spectra.
Analysis of Elliptical Rolling Contact Joints in Compression
Authors: Montierth Jacob R. , Todd Robert H. , Howell Larry L.
Published: February 2011

This paper presents elliptical rolling contact joints in compression as an alternative to circular rolling contact and conventional revolute joints where high quality force transmission—low friction and backlash—with variable output are desired. Parameters specific to the joint and its position are defined in terms of relative link angles and elliptical surface geometry. These relationships allow elliptical rolling contact joints to be incorporated in vector loop summations used in kinematic analysis. Notably, elliptical rolling contact is developed as the more general case of which circular rolling contact is a subset. Elliptical rolling contact joints are shown to offer several benefits over circular rolling contact, including reduced Hertz contact stresses, variable output velocity, maximum use of contact interface by distributing small rotations across surfaces of small curvature, reduced forces on constraining members, and no-slip pure rolling provided by either connecting links or flexures, without the need for gear teeth or friction.
Controlling the Polyethylene Molecular Weight Distribution Using Hydrogen Influent
Authors: Ali Emad M. , Al-haj Ali Mohammad
Published: February 2011

This paper addresses the feasibility of controlling the entire molecular weight distribution of the produced polymer in gas-phase ethylene polymerization reactors. Nonlinear model predictive controller is used to attain the control objective by utilizing the hydrogen feed rate as the only manipulated variable. The use of other manipulated variables is limited to avoid disturbing the process when influential inputs such catalyst and/or monomer inflows are used. The simulation results indicated successful implementation of the control algorithm to achieve the desired molecular weight distribution. The success depends on the improved hydrogen activities inside the reactor through a modified catalyst that is responsive to hydrogen variation and a wider admissible range of hydrogen feed rates.
Connection Vector Fields and Optimized Coordinates for Swimming Systems at Low and High Reynolds Numbers
Authors: Hatton Ross L. , Choset Howie
Published: February 2011

Several efforts have recently been made to relate the displacement of swimming three-link systems over strokes to geometric quantities of the strokes. While this approach has been successful for finding net rotations, noncommutivity concerns have prevented it from working for net translations. Our recent results on other locomoting systems have shown that the degree of this noncommutivity is dependent on the coordinates used to describe the problem, and that it can be greatly mitigated by an optimal choice of coordinates. Here, we extend the benefits of this optimal-coordinate approach to the analysis of swimming at the extremes of low and high Reynolds numbers.
Robust Design of a Micro-Electromechanical System in the Presence of Assembly Uncertainty
Authors: Rhee Choong-Ho , Oldham Kenn
Published: February 2011

Three methods of minimizing error between the transient response of a dynamic system with parameter variation and its nominal open-loop dynamics are tested on a second-order example system of a piezoelectric microactuator. The example system is a piezoelectrically actuated silicon flexure intended for use in micro-robotic systems. Polymer and silicon layers are to be stacked on top of the original flexure to increase out-of-plane weight-bearing capacity, but this process is subject to substantial alignment error. The procedures evaluated in this paper seek target stiffness and damping coefficients that minimize error in open-loop actuator motion. The first method is based on simple damping ratio and natural frequency calculations, while the second and third methods are based on state-space and transfer function models, respectively. All three approaches reduce error in transient dynamics compared to nominal designs based solely on static weight-bearing or fabrication considerations, with the state-based being identified as usable to a wide range of systems, although the ability to reduce sensitivity to model variation in purely open-loop operation is limited.
Control of Recurrent Neural Networks Using Differential Minimax Game: The Deterministic Case
Authors: Liu Ziqian , Ansari Nirwan
Published: February 2011

This paper presents a theoretical design of how a minimax equilibrium of differential game is achieved in a class of large-scale nonlinear dynamic systems, namely the recurrent neural networks. In order to realize the equilibrium, we consider the vector of external inputs as a player and the vector of internal noises (or disturbances or modeling errors) as an opposing player. The purpose of this study is to construct a nonlinear H∞ optimal control for deterministic noisy recurrent neural networks to achieve an optimal-oriented stabilization, as well as to attenuate noise to a prescribed level with stability margins. A numerical example demonstrates the effectiveness of the proposed approach.
Control of Recurrent Neural Networks Using Differential Minimax Game: The Stochastic Case
Authors: Liu Ziqian , Ansari Nirwan
Published: February 2011

As a continuation of our study, this paper extends our research results of optimality-oriented stabilization from deterministic recurrent neural networks to stochastic recurrent neural networks, and presents a new approach to achieve optimally stochastic input-to-state stabilization in probability for stochastic recurrent neural networks driven by noise of unknown covariance. This approach is developed by using stochastic differential minimax game, Hamilton-Jacobi-Isaacs (HJI) equation, inverse optimality, and Lyapunov technique. A numerical example is given to demonstrate the effectiveness of the proposed approach.
A Physically-Based, Control-Oriented Diesel Oxidation Catalyst (DOC) Model for the Applications of NO/NO2 Ratio Estimation Using a NOx Sensor
Authors: Hsieh Ming-Feng , Wang Junmin
Published: February 2011

NO and NO2 are generally considered together as NOx in engine emissions. Since NO2/NOx ratio is small in diesel engine exhaust gas, very often, existence of NO2 is ignored in studies/applications. However, current diesel aftertreatment systems generally include diesel oxidation catalysts (DOCs) at upstream of other catalysts such as diesel particulate filter (DPF) and selective catalytic reduction (SCR). DOC can significantly increase the NO2 fraction in the exhaust NOx. Because NO2 and NO have completely different reaction characters within catalysts, e.g. NO2 can assist DPF regeneration while NO cannot, and SCR De-NOx rate can be increased with higher NO2/NOx ratio (no more than 0.5), considerations of NO2 in aftertreatment systems are becoming necessary. Nevertheless, current onboard NOx sensors cannot differentiate NO and NO2 from NOx. This induces an interest in the method of estimating the concentrations of NO and NO2 in the exhaust gas by available measurements. In this paper, a physically-based, DOC control-oriented model which considers the NO and NO2 related dynamics and an engine exhaust NO/NO2 prediction method were proposed for the purposes of NO/NO2 ratio estimation in diesel engine aftertreatment systems, and the developed model was validated with experimental data.
Energy-Efficient Control Allocation for Over-Actuated Systems With Electric Vehicle Applications
Authors: Chen Yan , Wang Junmin
Published: February 2011

This paper presents a new control allocation (CA) scheme for improving operational energy-efficiency of over-actuated systems. By explicitly incorporating actuator efficiency functions into the CA formulation, minimum power consumption is achieved while distributing the desired virtual control among the redundant actuators. For some physical systems (e.g. hybrid electric or pure electric vehicles with electric motors) whose actuators have dual actuation modes (e.g. driving or regenerative braking of electric motors) that possess different efficiencies and/or energy consuming or gaining characteristics, a virtual actuator method is devised to augment the systems for the energy-efficient CA scheme. An electric vehicle model with rear/front axle motors or four in-wheel / hub motors constructed in the full-vehicle CarSim® simulation package is used as an application case study to show the effectiveness of the proposed energy-efficient CA method.
Switched Tracking Controller Design for Uncertain Systems
Authors: Yazdi Ehsan Azadi , Nagamune Ryozo
Published: February 2011

In this paper, a problem of designing a switched tracking dynamic output-feedback controller for uncertain systems is considered. The design problem amounts to solving an optimization problem, the cost function of which is neither smooth nor convex. By applying the proposed method to a nominal switched controller design methods, we designed a switched robust controller. Advantages of the method demonstrated through an example.
Modified Super-Twisting Interception Strategy With a Maximal Capture Zone
Authors: Glizer Valery Y. , Turetsky Vladimir , Fridman Leonid , Shinar Josef
Published: February 2011

A planar linearized interception problem of a maneuverable target is considered. A novel continuous interception strategy, based on the super-twisting second-order sliding mode control, is constructed. The sufficient conditions guaranteeing that this strategy has the maximal capture zone are established. Simulation results demonstrate that the control expenditure of the new strategy is reduced without deteriorating the homing performance in comparison with a bang-bang strategy.
A Cable-Driven Human Assistive System and Its Impedance Compensation by Sensor Fusion
Authors: Kong Kyoungchul , Bae Joonbum , Tomizuka Masayoshi
Published: February 2011

A cable-driven actuating system is proposed in this paper. The proposed system is attractive for human assistive devices because the weight of the actuator is not imposed on the human body. Since the end-effector and the actuators are connected by cables in flexible tubes, the humans are allowed to freely move in a certain range while being assisted. However, it is a challenge to account for the variable friction in the flexible tube and the inertia and friction of the actuator in the design of control algorithms. In this paper, a hierarchical control strategy is adopted to control the proposed cable-driven assistive system. To determine the reference trajectory of the motor in real-time, a sensor fusion method based on a kinematic Kalman filter with MEMS accelerometers is applied. By the proposed control methods, the proposed cable-driven system realizes a precise force-mode actuation.
Cable Friction Compensation and Rehabilitation Algorithms for a Cable-Driven Human Assistive System
Authors: Bae Joonbum , Kong Kyoungchul , Tomizuka Masayoshi
Published: February 2011

A cable-driven human assistive system has been developed to separate actuators from a human body. In the system, the assistive torque is transmitted via cables from the actuators to the end-effector which is to be attached on a human joint. The use of cables in flexible tubes allows for users to move freely without carrying the heavy actuators. However, the varying cable friction according to the curvature of the flexible tubes sets a challenge on the precise generation of the desired torque. To generate the desired torque precisely, a hierarchical control scheme is applied to the system. In this paper, the algorithms for determining the desired assistive joint torque and corresponding cable tensions are proposed. To determine the desired assistive torque, a rehabilitation strategy inspired by a potential field is discussed. For corresponding cable tensions, the algorithms for the cable tension controller which considers the varying cable friction as well as a bias for maintaining appropriate cable tensions are proposed. The performance of the proposed controller is verified by experiments.
Experimental Validation of a 2D Bristle Friction Force Model
Authors: Fillmore Steven , Liang Jianxun , Ma Ou
Published: February 2011

This paper describes an experimental effort designed to validate a general 2D bristle contact friction model. The model extends the 1D integrated bristle friction model to a 2D space by allowing the “bristle spring” to not only stretch along the direction of the bristle displacement but also rotate due to the instantaneous direction change of the velocity or motion trend in the common tangential plane of the contacting surfaces involved at the point of interest. The model is capable of simulating frictional behaviour in both sliding and sticking regimes occurring in general 3D rigid-body contact. With such an extension, the resulting friction model can be readily used to compute 3D contact friction forces in both sticking and sliding regimes. Two experiments were designed and implemented to validate the new 2D bristle model. The experiments were able to passively produce common frictional phenomena such as sliding, sticking, and stick-slip.
Model Predictive Control of a Distributed-Parameter Process Employing a Moving Radiant Actuator
Authors: Zeng Fan , Ayalew Beshah
Published: February 2011

Many industrial processes employ radiation-based actuators with two or more manipulated variables. Moving radiant actuators, in particular, act on a distributed parameter process where the velocity of the actuator is an additional manipulated variable with its own constraints. In this paper, a model predictive control (MPC) scheme is developed for a distributed-parameter process employing such a moving radiant actuator. The designed MPC controller uses an online optimization approach to determine both the radiant intensity and velocity of the moving actuator based on a linearized process model and a distributed state/parameter estimator. A particular source-model reduction that enables the approach is outlined. The proposed strategy is then demonstrated for a radiative curing process considering different control scenarios with the objective of achieving desired cure level uniformity and minimizing process energy use.
Compact Models of Terrain Surfaces
Authors: Chemistruck Heather , Ferris John B.
Published: February 2011

Terrain topology is the principal source of vertical excitation to the vehicle system and must be accurately represented in order to correctly predict the vehicle response. It is desirable to evaluate vehicle models and tire models over a wide range of terrain types, but it is computationally impractical to simulate long distances of every terrain variation. This work seeks to study the terrain surface, rather than the terrain profile, to maximize the information available to the tire model (i.e. wheel path data). A method to decompose the terrain surface as a combination of deterministic and stochastic components is presented. If some, or all, of the components of the terrain surface are considered to be stochastic, then the sequence can be modeled as a stochastic process. These stochastic representations of terrain surfaces can then be implemented in tire and vehicle models to predict chassis loads.