bluuebunny/crossref_metadata_2025 huggingface dataset:
SPECIAL POPULATIONS IN GERIATRICS
Authors: Miles Toni P. , Schwartz Ann V. , Villa Marie Luz , Prill Mila , Kelsey Joseph A. , Galinus Jill A. , Delay Romelia Ramirez , Nevitt Michael C. , Bloch Daniel A. , Marcus Robert , Kelsey Jennifer L.
Published: April 2015

OBJECTIVE: To determine the frequency of falls and identify risk factors for falls among older Mexican‐American women.

DESIGN: A prospective cohort study with an average follow‐up of 2.7 years.

SETTING: A clinical center at the Palo Alto Veterans Affairs Medical Center, California.

PARTICIPANTS: 152 community‐dwelling Mexican‐American Caucasian women aged 59 years or older.

OUTCOME MEASURES: Falls and injurious falls, as determined by monthly telephone interviews.

RESULTS: The rate of falls was 508 per 1000 person‐years (95% confidence interval (CI), 440–577). Injurious falls requiring medical attention occurred at a rate of 79 per 1000 person‐years (95% CI, 52–107). Factors that were associated independently with an increased risk of falling were older age, a history of arthritis or rheumatism, a history of high thyroid, having fainted at least once in the year before baseline, current use of psychotropic medications, and walking fewer than 5 blocks a day. Those persons with an average time for the chair stand test had a lower risk of falling than those with the slowest times or the fastest times.

CONCLUSIONS: The frequency of falls and injurious falls in this cohort of 152 relatively acculturated, healthy, older Mexican‐American women was similar or slightly higher than previously reported rates for non‐Hispanic Caucasian). Many of the factors associated with falls in this study were similar to those reported for non‐Hispanic Caucasian women, suggesting that fall prevention measures tested mainly among non‐Hispanic Caucasian women would also be appropriate for Mexican‐American women. J Am Geriatr Soc 47:1371–1378,1999.
Physical Activity, Functional Limitations, and Disability in Older Adults
Authors: Miller Michael E. , Rejeski W. Jack , Reboussin Beth A. , Ten Have Thomas R. , Ettinger Walter H.
Published: April 2015

OBJECTIVES: To explore initially how low levels of physical activity influence lower body functional limitations in participants of the Longitudinal Study of Aging. Changes in functional limitations are used subsequently to predict transitions in the activities of daily living/instrumental activities of daily living (ADL/IADL) disability, thus investigating a potential pathway for how physical activity may delay the onset of ADL/IADL disability and, thus, prolong independent living.

DESIGN: Analysis of a complex sample survey of US civilian, noninstitutionalized population aged 70 years and older in 1984, with repeated interviews in 1986, 1988, and 1990.

SETTING AND PARTICIPANTS: Analyses concentrated on 5151 men and women targeted for interview at all four LSOA interviews.

MEASUREMENTS: Characteristics used in analyses: gender, age, level of physical activity, comorbid conditions including the presence of hypertension, diabetes, arthritis, and atherosclerotic heart disease, levels of functional limitations, and ADL/IADL disability.

RESULTS: Transitional models provide evidence that older adults who have varying levels of disability and who report at least a minimal level of physical activity experience a slower progression in functional limitations (OR = .45, P < .001 for severe vs less severe limitations). This low level of physical activity, through its influence on changes in functional limitations, is shown to slow the progression of ADL/IADL disability.

CONCLUSIONS: Results from analyses provide supporting evidence that functional limitations can mediate the effect that physical activity has on ADL/IADL disability. These results contribute further to the increasing data that seem to suggest that physical activity can reduce the progression of disability in older adults.
Predictors for Functional Decline Among Nondisabled Older Japanese Living in a Community During a 3‐Year Follow‐Up
Authors: Ishizaki Tatsuro , Watanabe Shuichiro , Suzuki Takao , Shibata Hiroshi , Haga Hiroshi
Published: April 2015

OBJECTIVES: To examine predictors for functional decline in basic activities of daily living (BADL) as well as predictors for decline in instrumental activities of daily living (IADL) among nondisabled older Japanese people living in a community during a 3‐year interval from 1992 to 1995.

DESIGN: A prospective cohort study.

SETTING: A community‐based environment.

PARTICIPANTS: A total of 583 men and women aged 65 to 89 at baseline who were independent in both BADL and IADL.

MEASUREMENTS: Independent variables regarding various factors potentially associated with functional decline were obtained from an interview survey and medical examinations at baseline. Dependent variables were functional status in BADL and IADL obtained at the time of the 3‐year follow‐up.

RESULTS: During the 3‐year follow‐up, significant predictors for functional decline in BADL and only IADL decline included (1) age of ≥75, (2) less hand‐grip strength, and (3) a history of hospitalization during the past 1 year. In addition, having poor intellectual activities and having poor social roles were identified as significant predictors for functional decline in only IADL during the 3‐year follow‐up. Furthermore, not having the habit of taking a walk was identified as a significant predictor of functional decline in BADL during the 3‐year interval.

CONCLUSION: Having a high level hand‐grip strength, good intellectual activities, and good social roles are strongly associated with remaining independence in IADL for the nondisabled Japanese persons aged ≥65.
Subjective Memory Complaint in Relation to Cognitive Performance and Depression: A Longitudinal Study of a Rural Chinese Population
Authors: Wang Pei‐Ning , Wang Shuu‐Jiun , Fuh Jong‐Ling , Teng Evelyn Lee , Liu Chia‐Yih , Lin Cheng‐Huai , Shyu Hann‐Yeh , Lu Sbiang‐Ru , Chen Chao‐Ching , Liu Hsiu‐Chih
Published: April 2015

OBJECTIVES: To examine the associations of subjective memory complaint (SMC) in old age with (a) objective test performance, (b) past and subsequent cognitive decline, and (c) depression.

DESIGN: A group of community residents were examined twice during a 3‐year period.

SETTING: Two townships on a rural Chinese islet.

PARTICIPANTS: A total of 543 men and women aged 65 years and older.

MEASUREMENTS: During each examination, neurologists interviewed and examined all participants for dementia and asked the question, “Do you have trouble with your memory?” In addition, research assistants administered (a) the Cognitive Abilities Screening Instrument (CASI) to assess cognitive abilities, including long‐term memory (LTM) and short‐term memory (STM), and (b) the Geriatric Depression Scale‐Short Version (GDS‐S) to assess symptoms of depression.

RESULTS: At each examination, almost half of the subjects acknowledged having trouble with their memory (the SMC+ group). At both examinations, the SMC+ group scored significantly lower on the CASI and significantly higher on the GDS‐S than the SMC− group. However, the presence of SMC was not associated with faster cognitive decline over the past or subsequent 3 years. There were no consistent associations between SMC and the demographic variables of age, gender, and education at the two examinations. Logistic regression analysis showed that SMC was associated with poorer memory test scores after controlling for gender, age, education, and depression.

CONCLUSIONS: SMC was associated with poorer objective memory performance even after controlling the effect of depression and demographic data, but SMC did not predict faster cognitive decline or dementia over 3 years. J Am Geriatr Soc 48: 295–299, 2000.
Dying with Acute Respiratory Failure or Multiple Organ System Failure with Sepsis
Authors: Somogyi‐Zalud Emese , Zhong Zhenshao , Lynn Joanne , Dawson Neal V. , Hamel Mary Beth , Desbiens Norman A.
Published: April 2015

BACKGROUND: The dying experience of patients with acute respiratory failure (ARF) or multiple organ system failure with sepsis (MOSF) has not been described.

OBJECTIVES: To describe patients dying from ARF or MOSF, including demographic characteristics, baseline function and quality of life, symptoms, preferences, use of life‐sustaining treatments, satisfaction with care, and family burden.

DESIGN: A multicenter prospective study.

SETTING: Five US teaching hospitals, in the Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatments (SUPPORT).

PARTICIPANTS: A total of 1295 adults who died during hospitalization for ARF or MOSF.

MEASUREMENTS: Chart reviews and interviews with patients and surrogates.

RESULTS: SUPPORT enrolled 2956 patients with ARF or MOSF, and 44% died during enrollment hospitalization. Quality of life before hospitalization was reported as fair by 87% of patients. The mean number of impairments in their baseline activities of daily living was 1.6. At the time of death, 79% had a DNR order and 31% had an order to withhold ventilator support. The average time from the DNR order to death was 2 days. Dying patients spent an average of 9 days on a ventilator. Surrogates indicated that one out of four patients died with severe pain and one out of three with severe confusion. Families of 42% of the patients who died reported one or more substantial burden.

CONCLUSIONS: Patients in this study reported substantial functional impairments and reduced quality of life. Limitations to aggressive treatments were usually implemented only when death was imminent. Family impact and physical and emotional suffering were substantial.
Pain and Suffering in Seriously Ill Hospitalized Patients
Authors: Desbiens Norman A. , Wu Albert W.
Published: April 2015

BACKGROUND: Previous studies had suggested a high prevalence of pain in hospitalized patients but had not specifically evaluated pain and other symptoms in seriously ill and older hospitalized patients.

OBJECTIVE: The SUPPORT and HELP studies were designed to (1) assess the frequency and severity of pain and other symptoms during hospitalization 2 and 6 months later, and before death; (2) identify factors associated with pain and other symptoms; and (3) test an intervention to improve pain.

DESIGN: An observational cohort and randomized controlled trial.

SETTING: Five major teaching hospitals in the US.

PATIENTS: Hospitalized patients aged 80 years and older or with one of nine serious illnesses.

INTERVENTION: Education of patients and family members about pain control, monitoring of patients' pain, and feedback about pain with treatment suggestions to nurses and physicians.

MEASUREMENTS: Data from the medical record and interview‐based information about pain and other symptoms and preferences for care and symptom control from patients and family members.

RESULTS: Pain and other symptoms were frequent and often severe in seriously ill and older patients during hospitalization, at follow‐up, and before death, even in those with diseases not traditionally associated with pain. There was wide variation in symptom experience across hospitals. Patients' preference for pain control was not associated with symptom experience. The intervention did not improve pain control.

CONCLUSIONS: Control of pain and other symptoms remains an important medical and ethical issue. Routine monitoring of pain and other symptoms should be linked to treatment strategies aimed at combinations of symptoms and tested to assuage concerns about side effects.
Predicting Adverse Postoperative Outcomes in Patients Aged 80 Years or Older
Authors: Liu Linda L. , Leung Jacqueline M.
Published: April 2015

OBJECTIVE: The identification of reversible factors that are associated with postoperative morbidity in geriatric surgical patients is critical to improving perioperative outcomes in such patients. Our study aimed to compare the relative importance of intraoperative versus preoperative factors in predicting adverse postoperative outcomes in geriatric patients.

DESIGN: Retrospective cohort study of consecutive patients undergoing noncardiac surgery in 1995.

SETTING: Two University of California, San Francisco, teaching hospitals—Moffitt/Long and Mount Zion medical centers.

PARTICIPANTS: All men and women 80 years of age or older undergoing noncardiac surgery.

MEASUREMENTS: Medical records of all patients were reviewed to measure predefined pre‐ and intraoperative risk factors and postoperative outcomes. Predictors of postoperative outcomes were identified by multivariate logistic regression analyses.

RESULTS: Three hundred sixty‐seven patients were studied. The most prevalent preoperative risk factors were a history of hypertension and coronary artery, pulmonary, and neurologic diseases. Postoperative in‐hospital mortality rate was 4.6%, and 25% of patients developed adverse postoperative outcomes, of which neurological and cardiovascular complications were the leading causes of morbidity (15% and 12%, respectively). By multivariate logistic regression, a history of neurological disease (odds ratio [OR] 4.0, 95% confidence interval [CI] 2.3 – 6.9, P = .0001), congestive heart failure (OR 2.7, 95% CI 1.4 – 5.3, P = .004), and a history of arrhythmia (OR 2.3, 95% CI 1.2 – 4.3, P = .01) increased the odds of adverse postoperative events. The only intraoperative event shown to be predictive of postoperative complications was the use of vasoactive agents (OR 8.0,95% CI 1.6 – 40.5, P = .009).

CONCLUSIONS: In this group of geriatric surgical patients, the overall postoperative in‐hospital mortality rate was 4.6%, and 25% of the patients developed adverse postoperative outcomes involving either the neurological, cardiovascular, or pulmonary systems. Intraoperative events appeared to be less important than preoperative comorbidities in predicting adverse postoperative outcomes. J Am Geriatr Soc 48: 405–412, 2000.
The Association Between Parkinsonism, Alzheimer's Disease, and Mortality: A Comprehensive Approach
Authors: Mitchell Susan L. , Rockwood Kenneth
Published: April 2015

BACKGROUND: The impact of parkinsonism on survival in older persons independent of dementia is not well understood.

METHODS: Participants in the clinical examination of the Canadian Study of Health and Aging who had parkinsonism and were older than age 65 were identified. The impact of parkinsonism on 5‐year survival was determined for a combined cohort with and without dementia, and a stratified analysis was then conducted for the subgroups with Alzheimer's disease (AD) and those without dementia. Subjects with a previous diagnosis of Parkinson's disease and those prescribed drugs causing extrapyramidal side effects were excluded.

FINDINGS: A total of 721 subjects with AD and 1705 subjects without dementia were examined. After adjusting for age and residential status (community vs institution), parkinsonism was associated with poorer survival in the combined cohort (risk ratio 1.51; 95% CI, 1.22–1.85), in those with AD (risk ratio 1.34; 95% CI, 1.02–1.76), and those without dementia (risk ratio 1.54; 95% CI, 1.11–2.15). In the combined cohort, parkinsonism remained independently associated with higher mortality after adjusting for AD status (risk ratio 1.39; 95% CI, 1.13–1.72). In the subgroup with AD, parkinsonism remained associated with poorer survival after adjusting for severity of cognitive impairment (risk ratio 1.33; 95% CI. 1.04–1.74).

INTERPRETATION: Parkinsonism is significantly associated with poorer survival in older persons, regardless of whether they have dementia.J Am Geriatr Soc 48: 422–425, 2000.
Hormone Replacement Therapy Use in Urban Older Women Attending Meal Sites: Associations with Sociodemographic and Health Characteristics and Use of Preventive Services
Authors: Ganesan Kalpana , Teklehaimanot Senait , Swartz Joel B. , Reuben David B.
Published: April 2015

OBJECTIVE: To examine sociodemographic, health and preventive health practices associated with hormone replacement therapy (HRT) use in urban community‐dwelling older women.

DESIGN: Survey.

SETTING: Community‐based meal sites throughout the city of Los Angeles.

PARTICIPANTS: A convenience sample of 705 community‐dwelling women older than age 60 who completed questionnaires for the Prevention for Elderly Persons Program.

MEASUREMENTS: Demographic and life style characteristics, functional status, preventive practices, and current and past use of HRT.

RESULTS: Among the 705 women surveyed, 13% reported current use and 17% reported past use of HRT. Current users were more likely to be younger and more likely to report a history of osteoporosis, hysterectomy, and calcium use than never users. White women were more likely to be current users than black women.

CONCLUSIONS: Only a small proportion of the older urban women studied are currently using HRT. In particular, efforts to increase the use of these preventive services need to focus on black women and women who do not have a prior history of osteoporosis. J Am Geriatr Soc 48:669–672, 2000.
The Involvement of Physicians in VA Home Care: Results From a National Survey
Authors: Weaver Frances M. , Hughes Susan L. , Giobbie‐Hurder Anita , Ulasevich Alec , Kubal Joseph D. , Fuller Jon , Kinosian Bruce , Lichtenstein Michael J. , Rowe Joseph
Published: April 2015

OBJECTIVES: To examine the role of physicians in the Veteran Affairs (VA) home‐based primary care (HBPC) program and to identify variables that predict whether physicians make home visits and volume of home visits made.

DESIGN: Descriptive and regression analyses of responses from a mail survey.

PARTICIPANTS: Forty‐five physicians affiliated with VA HBPC programs.

MAIN SURVEY TOPICS: Self‐reported work load, attitudes toward home care, reasons for home visits, administrative policies regarding physicians' role in patient care management, and time commitment to home care.

RESULTS: A majority of physicians believed strongly in the importance of home care and made home visits for reasons consistent with their training. Physician attitude toward home care and preoccupation with office or hospital practice were related to whether or not physicians made home visits. Degree of preoccupation with office practice and amount of salary support from VA HBPC were significant predictors of the number of visits made (Rs2 = 0.44).

CONCLUSIONS: These findings indicate that most physicians will make home visits if they believe that home care is valuable and if their time commitment is supported financially. Managed care plans that own and operate home care programs and have the capacity to transfer primary care management to physicians who derive financial support from the programs should find this information particularly relevant. J Am Geriatr Soc 48:677–681, 2000.
IGF‐1 AND ISCHEMIC HEART DISEASE IN OLDER PEOPLE
Authors: Goodman‐Gruen Deborah , Barrett‐Connor Elizabeth
Published: April 2015

Clifford Rosen, MD2
A Population‐Based Study on Motor Performance and White Matter Lesions in Older Women
Authors: Guo Xinxin , Skoog Ingmar , Matousek Michael , Larsson Lena , Palsson Sigurdur , Sundh Walter , Steen Bertil
Published: April 2015

OBJECTIVE: To investigate the relationship between motor performance and white matter lesions (WMLs) on computed tomography (CT) of the brain in older women.

DESIGN: Cross‐sectional study.

SETTING: Population‐based study in Göteborg, Sweden.

PARTICIPANTS: A total of 248 women aged 70, 74, and 78 years.

MEASUREMENTS: Motor performance was measured by a Postural‐Locomotion‐Manual (PLM) test using an optoelectronic technique. WMLs on CT scans were rated as no, mild, moderate, or severe.

RESULTS: White matter lesions were associated with impaired mobility of the lower extremities, that is, prolonged locomotion phase in the PLM test. This association was also present after controlling for age, hypertension, coronary heart disease, stroke, diabetes mellitus, chronic bronchitis, intermittent claudication, and smoking.

CONCLUSIONS: Cerebral white matter lesions may contribute to motor impairments in older adults. J Am Geriatr Soc 48:967–970, 2000.
Periodontal status and pathogenic bacteria after gastric bypass: a cohort study
Authors: Sales‐Peres Sílvia Helena de Carvalho , de Moura‐Grec Patrícia Garcia , Yamashita Joselene Martinelli , Torres Elza Araujo , Dionísio Thiago José , Leite Celso Vieira de Souza , Sales‐Peres Arsenio , Ceneviva Reginaldo
Published: April 2015

Aim

The aim this study was to evaluate the influence of gastric bypass surgery (GBS) on periodontal disease and quantify the periodontopathogenic bacteria in patients undergoing this surgery.

Material and Methods

This prospective study was composed of 50 patients who underwent bariatric surgery and the data collection was performed in three periods pre‐operative, 6 (6M) and 12 months (12M) postoperative. The oral clinical examination to assess periodontal disease; gingival fluid sample collection for quantification of the periodontopathogenic bacteria Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, and Prevotella intermedia using q‐PCR; body mass index (BMI) and for collection of the individual's health‐related data from medical files.

Results

There was a significant reduction in serum C‐reactive protein (CRP) and glucose levels after surgery. The mean probing pocket depth (PPD) and clinical attachment level (CAL) increased significantly in the postoperative period of 6 months (p = 0.001). In the same period, the amount of P. gingivalis increased (p = 0.028) and the other bacteria decreased slightly (p > 0.050). In the presence of P. gingivalis, T. forsythia, T. denticola and P. intermedia, a poor periodontal condition was observed.

Conclusion

The periodontal disease increased in severity and P. gingivalis increased after GBS. A systemic inflammation resolution due to bariatric surgery in obese subjects does not seem to affect the course of periodontal disease.
In vitro toxicity of propolis in comparison with other primary teeth pulpotomy agents on human fibroblasts
Authors: Al‐Haj Ali Sanaa Najeh
Published: April 2015

Aim

The aim of this study was to assess and compare the in vitro toxicity of propolis with other primary teeth pulpotomy medicaments.

Methods

Human periodontal ligament (PDL) cells were subjected to different concentrations of propolis, formocresol, ferric sulfate, and gray mineral trioxide aggregate (MTA) (0.05, 0.5, 5, 50, and 100 μg/mL) for 24 h at 37°C. Cells that were not exposed to the tested materials served as the negative control. In vitro toxicity was assessed using 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay. Statistical analysis of the data was accomplished using anova and Tukey statistical tests (P < 0.05).

Results

Only propolis and gray MTA had comparable cell viability to the negative control group. Almost all remaining concentrations of tested materials were significantly inferior to the negative control after 24 h of exposure (P < 0.05).

Conclusion

Propolis and MTA are more biocompatible than formocresol and ferric sulfate since they were both able to preserve PDL fibroblasts for up to 24 h.
Out‐of‐focus background subtraction for fast structured illumination super‐resolution microscopy of optically thick samples
Authors: VERMEULEN P. , ZHAN H. , ORIEUX F. , OLIVO‐MARIN J.‐C. , LENKEI Z. , LORIETTE V. , FRAGOLA A.
Published: April 2015

We propose a structured illumination microscopy method to combine super resolution and optical sectioning in three‐dimensional (3D) samples that allows the use of two‐dimensional (2D) data processing. Indeed, obtaining super‐resolution images of thick samples is a difficult task if low spatial frequencies are present in the in‐focus section of the sample, as these frequencies have to be distinguished from the out‐of‐focus background. A rigorous treatment would require a 3D reconstruction of the whole sample using a 3D point spread function and a 3D stack of structured illumination data. The number of raw images required, 15 per optical section in this case, limits the rate at which high‐resolution images can be obtained. We show that by a succession of two different treatments of structured illumination data we can estimate the contrast of the illumination pattern and remove the out‐of‐focus content from the raw images. After this cleaning step, we can obtain super‐resolution images of optical sections in thick samples using a two‐beam harmonic illumination pattern and a limited number of raw images. This two‐step processing makes it possible to obtain super resolved optical sections in thick samples as fast as if the sample was two‐dimensional.
The use of Botulinum toxin‐A injection for facial wrinkles: a histological and immunohistochemical evaluation
Authors: El‐Domyati Moetaz , Attia Sameh K. , El‐Sawy Ashraf E. , Moftah Noha H. , Nasif Ghada A. , Medhat Walid , Marwan Belkais
Published: April 2015

Botulinum toxin (BTX)‐A has been used for years in the reduction of facial wrinkles; however, histological and immunohistochemical changes after its use were not previously investigated. To evaluate histological and immunohistochemical changes after BTX‐A injection for facial wrinkles, sixteen volunteers, with wrinkles on the upper third of the face, were subjected to single injection of BTX‐A. Skin biopsy specimens were obtained from peri‐orbital wrinkle site (crow's feet area) before and after 3 months of BTX‐A injection. Using histological and immunohistochemical evaluation coupled with computerized morphometric analysis, measurement of epidermal thickness, wrinkle depth and width as well as quantitative evaluation of collagen types I and III and elastin was performed for skin biopsies. After BTX‐A injections, there were significant increase in wrinkle width and granular layer thickness (P < 0.001), while the other histometrical measures as well as the immunohistochemical expression of collagen types I and III and elastin showed no significant difference (P > 0.05). However, collagen fibers showed better organization and orientation after BTX‐A injection. The histological changes observed after BTX‐A injection for facial wrinkles may help in better understanding of its mechanism of action.
CEO Preferences and Acquisitions
Authors: JENTER DIRK , LEWELLEN KATHARINA
Published: May 2015

This paper explores the impact of target CEOs’ retirement preferences on takeovers. Using retirement age as a proxy for CEOs’ private merger costs, we find strong evidence that target CEOs’ preferences affect merger activity. The likelihood of receiving a successful takeover bid is sharply higher when target CEOs are close to age 65. Takeover premiums and target announcement returns are similar for retirement‐age and younger CEOs, implying that retirement‐age CEOs increase firm sales without sacrificing premiums. Better corporate governance is associated with more acquisitions of firms led by young CEOs, and with a smaller increase in deals at retirement age.
Rapid evolution of a consumer stoichiometric trait destabilizes consumer–producer dynamics
Authors: Yamamichi Masato , Meunier Cédric L. , Peace Angela , Prater Clay , Rúa Megan A.
Published: April 2015

Recent studies have shown that adaptive evolution can be rapid enough to affect contemporary ecological dynamics in nature (i.e. ‘rapid evolution’). These studies tend to focus on trait functions relating to interspecific interactions; however, the importance of rapid evolution of stoichiometric traits has been relatively overlooked. Various traits can affect the balance of elements (carbon, nitrogen, and phosphorus) of organisms, and rapid evolution of such stoichiometric traits will not only alter population and community dynamics but also influence ecosystem functions such as nutrient cycling. Multiple environmental changes may exert a selection pressure leading to adaptation of stoichiometrically important traits, such as an organism's growth rate. In this paper, we use theoretical approaches to explore the connections between rapid evolution and ecological stoichiometry at both the population and ecosystem level. First, we incorporate rapid evolution into an ecological stoichiometry model to investigate the effects of rapid evolution of a consumer's stoichiometric phosphorus:carbon ratio on consumer–producer population dynamics. We took two complementary approaches, an asexual clonal genotype model and a quantitative genetic model. Next, we extended these models to explicitly track nutrients in order to evaluate the effect of rapid evolution at the ecosystem level. Our model results indicate rapid evolution of the consumer stoichiometric trait can cause complex dynamics where rapid evolution destabilizes population dynamics and rescues the consumer population from extinction (evolutionary rescue). The model results also show that rapid evolution may influence the level of nutrients available in the environment and the flux of nutrients across trophic levels. Our study represents an important step for theoretical integration of rapid evolution and ecological stoichiometry.
How does the healthcare system affect medication self‐management among older adults with multimorbidity?
Authors: Meranius Martina Summer , Hammar Lena Marmstål
Published: April 2015

Individuals with multimorbidity commonly have several concurrent prescriptions and experience healthcare obstacles related to managing different diagnoses and medications. This study aimed to provide a deeper understanding of how older adults with multimorbidity experience medication self‐management and how this is affected by the healthcare system. The National Board of Research Ethics approved the study, and 20 older adults with multimorbidity participated in in‐depth interviews that were analysed using a hermeneutic approach. Three levels of interpretation emerged. At the first level, lack of participation in healthcare communication hinders adherence and safety, and feeling abandoned to self‐care leads to health risk‐taking. At the second level, the healthcare organisation is seen as an obstacle to medication self‐management. The overall interpretation was a system of repairing ‘parts’ but not enabling the experience of health. This study shows that the healthcare system is able to treat and relieve an individual's symptoms, but seems unable to help them achieve and promote good health, or to provide the support they need to function in everyday life.
Use of Antiepileptic Drugs in Patients with Chronic Kidney Disease and End Stage Renal Disease
Authors: Bansal Amar D. , Hill Chloe E. , Berns Jeffrey S.
Published: May 2015

Epilepsy is a disorder with an approximate worldwide prevalence of 1%. Due to complexities of metabolism, protein‐binding, renal elimination, and other pharmacokinetic parameters, the dosing of antiepileptic drugs (AEDs) in patients with chronic kidney disease (CKD) or end stage renal disease (ESRD) deserves special attention. This is a review of the most commonly prescribed AEDs with special focus on their indication, pharmacokinetics, and unique considerations for use in patients with CKD and ESRD. A review of their renal toxicities is also included.
Thromboelastographic assessment of the contribution of platelets and clotting proteases to the hypercoagulable state of dogs with immune‐mediated hemolytic anemia
Authors: Hamzianpour Negar , Chan Daniel L.
Published: April 2015

Background

Hypercoagulability is a well‐known feature of canine immune‐mediated hemolytic anemia (IMHA) and is believed to increase the risk of thrombosis. This study was undertaken to differentiate the relative contribution of platelets and clotting proteases to this hypercoagulability using thromboelastography (TEG).

Study Design

Retrospective observational study.

Methods

Thromboelastograms from 27 dogs with IMHA were retrospectively evaluated. Standard TEG parameters (R, K, α, MA), the G value, and the novel parameter delta (Δ) were determined. Hypercoagulability was attributed to the platelet component of hemostasis when there was an increased G value with a normal Δ value.

Key Findings

Nineteen of 27 dogs (70.4%) had ≥ 2 TEG variables suggestive of hypercoagulability, 18 (66.7%) had a hypercoagulable G value, and 11 (40.7%) had a hypercoagulable Δ value. Ten of 27 (37%) samples met the criteria for platelet hypercoagulability.

Significance

Our report documents the derivation and application of the Δ value to differentiate enzymatic from platelet hypercoagulability. Further studies are required to validate the use of these TEG variables in this manner. The hypercoagulable tendency in dogs with IMHA is complex and multifactorial, and in some dogs this hypercoagulability may be attributed primarily to platelet hyper reactivity. Our findings may support the use of anti‐platelet drugs in some dogs with IMHA.
Sir Joseph Barcroft: one victorian physiologist's contributions to a half century of discovery
Authors: Longo Lawrence D.
Published: May 2015

During the first half of the 20th Century, Joseph Barcroft, KBE, FRS of Cambridge University became a world leader in respiratory physiology. He determined the role of neural stimulation in the oxygen consumption of several organs, established many of the factors that regulate the binding of oxygen to haemoglobin, explored the determinants of a human's acclimatization to high altitude and developed the field of fetal cardiovascular physiology. Chair of the Cambridge Department of Physiology from 1925 to 1937, he served as a consultant and member of many UK governmental committees. During World War I, he led a British research unit exploring the effects of poisonous gases on pulmonary function and related problems. In addition to his almost 300 publications, several of his monographs are considered as classics.
Understanding the Impact of Subjective Uncertainty on Architecture and Supplier Identification in Early Complex Systems Design
Authors: Ye Yun , Jankovic Marija , Kremer Gül E.
Published: April 2015

The Architecture and Supplier Identification Tool (ASIT) is a design support tool, which enables identification of the most suitable architectures and suppliers in early stages of complex systems design, with consideration of overall requirements satisfaction and uncertainty. During uncertainty estimation, several types of uncertainties that are essential in early design (i.e., uncertainty of modules due to new technology integration, compatibility between modules, and supplier performance uncertainty) have been considered in ASIT. However, it remains unclear whether uncertainty due to expert estimation should be taken into account. From one perspective, expert estimation uncertainty may significantly influence the overall uncertainty, since early complex systems design greatly depends on expert estimation; whereas an opposing perspective argues that expert estimation uncertainty should be neglected given its relatively much smaller scale. In order to understand how expert estimation uncertainty influences the architecture and supplier identification, a comprehensive study of possible modeling approaches has been discussed within the context of ASIT; type-1 fuzzy sets and 2-tuple fuzzy linguistic representation are selected to integrate subjective uncertainty into ASIT. A powertrain design case is used to compare results between cases considering subjective uncertainty versus cases not considering subjective uncertainty. Finally, implications of considering subjective uncertainty in early conceptual design are discussed.
Design and Experimental Testing of an Improved Large-Range Decoupled XY Compliant Parallel Micromanipulator1
Authors: Yu Jingjun , Xie Yan , Li Zhenguo , Hao Guangbo
Published: April 2015

There is an increasing need for XY compliant parallel micromanipulators (CPMs) providing good performance characteristics such as large motion range, well-constrained cross-axis coupling, and parasitic rotation. Decoupled topology design of the CPMs can easily realize these merits without increasing the difficulty of controlling. This paper proposes an improved 4-PP model on the basis of a classical 4-PP model and both of them are selected for manufacturing and testing to verify the effectiveness of the improvement. It has shown from experimental results that there is a large improvement on the performances of improved 4-PP compliant parallel manipulator (CPM): large range of motion up to 5 mm × 5 mm in the unidirection in the dimension of 311 mm × 311 mm × 24 mm, smaller compliance fluctuation (only 36.63% of that of the initial 4-PP model), smaller cross-axis coupling (only 28.10% of that of the initial 4-PP model generated by a single-axis 5 mm actuation), smaller in-plane parasitic yaw (only 57.14% of that of the initial 4-PP model generated by double-axis 5 mm actuation).
Hierarchical Kinematic Design of Foldable Hexapedal Locomotion Platforms
Authors: Faal Siamak G. , Chen Fuchen , Tao Weijia , Agheli Mahdi , Tasdighikalat Shadi , Onal Cagdas D.
Published: April 2015

Origami-inspired folding enables integrated design and manufacturing of intricate kinematic mechanisms and structures. Here, we present a hierarchical development process of foldable robotic platforms as combinations of fundamental building blocks to achieve arbitrary levels of complexity and functionality. Rooted in theoretical linkage kinematics, designs for static structures and functional units, respectively, offer rigidity and mobility for robotic systems. The proposed approach is demonstrated on the design, fabrication, and experimental verification of three distinct types of hexapedal locomotion platforms covering a broad range of features and use cases.
Increased Life for Gas Turbine Combustion Systems Burning Residual Fuel
Authors: MaCaulay R. W. , Gardiner C. M.
Published: May 2015

ASME Paper 48-A-109 described combustion liners and fuel nozzles which were originally used in General Electric gas turbines. Operating experience has shown certain shortcomings of these, particularly in regard to liner life and frequency of changing required by the fuel nozzles. This paper describes a new type of liner and fuel nozzle which, on the basis of limited field experience, have shown considerable improvement in these respects. It also gives a brief review of test data and operating experience on combustion liners and fuel nozzles.
The Liquid Metal Fuel Reactor Closed-Cycle Gas Turbine Power Plant
Authors: Stoughton L. D. , Sheehan T. V.
Published: May 2015

A nuclear power plant is proposed which combines the advantages of a liquid metal fueled reactor with those inherent in a closed cycle gas turbine. The reactor fuel is a solution of uranium in molten bismuth which allows for unlimited burn-up with continuous fuel make-up and processing. The fuel can either be contained in a graphite core structure or circulated through an external heat exchanger. The cycle working fluid is an inert gas which is heated by the reactor fuel before entering the turbine. A 15 MW closed cycle gas turbine system is shown to illustrate the application of this reactor.
Determination of Turbine Stage Performance for an Automotive Power Plant
Authors: Mann L. B. , Bell A. H. , Thebert G. W.
Published: May 2015

The experimental investigation of turbine-stage performance in a component test facility is presented. The test variables are combined into working parameters and these are used to develop a convenient test procedure. Fixture equipment, specialized instrumentation and the related methods are discussed. Test results from a typical automotive turbine stage are presented.
Gas Turbine Generating Experience of West Texas Utilities Company
Authors: Cox A. R.
Published: May 2015

A summary of West Texas Utilities Company’s gas-turbine generating experience covering operation and maintenance during the period between December, 1952, and August, 1956. Tabulated operating and maintenance cost is included.
A New Single Shaft 3000-HP Gas Turbine Ideal for Mechanical Drive Application
Authors: Yindra J.
Published: May 2015

This paper describes the design and construction of a new 3000-hp single-shaft gas turbine which has been designed for sufficient speed flexibility to make it ideal for mechanical drive applications. Over-all performance and efficiencies of the gas turbine are presented together with a description of the control system and its application to variable-speed drives. A simplified electrohydraulic control system is described which retains necessary protective features and minimizes the accessory equipment. Particular emphasis has been placed on refinery applications where reliability is paramount.
Gas-Turbine Maintenance in Severe Service
Authors: Hill Ross C.
Published: May 2015

There are probably some power plants which operate under more severe conditions than do railroad locomotives. However, when all factors are considered, it is apparent that locomotive service is a severe test for any type of engine and associated control. This condition makes it necessary for locomotive builders and equipment manufacturers to re-evaluate many of their design practices. In order to adapt equipment designed for aircraft life or stationary plant conditions to railroad service, much more attention must be given to strength and sealing.
Design Considerations for Marine Gas Turbines
Authors: Spurrier F. R.
Published: May 2015

A gas-turbine engine employed as the main propulsion plant in a ship must satisfy design requirements which differ considerably from those for other turbine applications. The design objectives in a gas-turbine plant for application to naval vessels of medium displacement are discussed in this paper. Such vessels, notably escort types, have duty profile characteristics which demand relatively short periods of operation at maximum power, and long periods at small percentages of maximum power. Normal cruising power may be only 15 per cent of the maximum available but economy of operation must be assured at this condition. In this respect, such engines introduce problems which do not arise in commercial vessels or aircraft-machines, where most of the operating life is spent at high percentages of the maximum available power.
Gas Turbines for the Chemical Industry
Authors: Stys Z. Stanley
Published: May 2015

Application of the gas turbine in nitric-acid plants appears attractive. Several of these units have been installed recently in this country and performance and operating experience already have been gained. Design, construction, and layout of “package” units for this particular process are described.
A Model W-121 Gas Turbine for Power Generation and Mechanical Drive
Authors: Strong R. E.
Published: May 2015

This paper presents the basic design of a Model W-121 gas turbine with a nominal rating of 12,000 hp and 8500 kw for mechanical and electrical drive applications. The over-all performance and efficiency are presented together with a description of the essential features of construction and design of the basic components.
Nonsteady Aerodynamics of the Comprex Supercharger
Authors: Burri Hans U.
Published: May 2015

A brief outline is given of the method of characteristics for the analysis of one-dimensional nonsteady flow. Two typical types of experiments are discussed which indicate the degree of accuracy possible if this method is applied to machinery like the Comprex supercharger. As an example, a typical analysis is presented for one particular engine-performance point. It is possible to duplicate engine test results with acceptable accuracy.
Operating Experience of General Electric Gas Turbines
Authors: McLean H. D.
Published: May 2015

A review is made of all General Electric Company Gas Turbines installed and operated previous to January 1, 1958. The gas turbines are reviewed with respect to application, fuels burned, fired hours, and miscellaneous features. Each different basic design is briefly described, with date of first operation and total number installed given. Gas turbine failures that have occurred in operation are discussed.

Availability, reliability, and use factors are given. A brief review of published articles by gas turbine owners and operators is made. Problems that have occurred in eight and one-half years of operation are discussed, and solutions are given. Maintenance requirements and life of gas-path parts are discussed.

A brief description of future activity, new basic designs, new features, and new installations is included.
Small-Scale Burner Tests to Investigate Oil-Ash Corrosion
Authors: Amero R. C. , Rocchini A. G. , Trautman C. E.
Published: May 2015

About 125 small-scale burner tests were run to investigate high-temperature corrosion of alloy steel by ash from residual fuel oils. In most of these tests a specimen of AISI-310 stainless steel (25-20 Cr-Ni alloy) was exposed for 100 hours at 1450°F. to the combustion gases of No, 6 or Burner Fuel Oil-Navy Special containing 150–200 ppm vanadium, without or with experimental additives. The small-scale burners and a full-scale ten-inch combustor (from a Westinghouse gas turbine) operated at substantially atmospheric pressure showed very good agreement with respect to corrosion and deposits formed in 27 comparative tests.
Operating Experience With 750/1000-KW Gas Turbines
Authors: Feilden G. B. R. , Latimer T. P.
Published: May 2015

After giving a brief survey of some of the salient design features of the Mark TA 750/1000-kw gas turbine, an account is given of some of the different categories of application found for this machine on all six Continents of the World, indicating the economic factors which have led to the selection of gas turbines rather than alternative types of prime mover. The main portion of the paper deals with the operating experience which has been obtained on turbines burning natural gas, distillate, and crude oil fuels. The operation of twenty-nine Mark TA turbines which are now in service has been noteworthy for its complete freedom from blade breakages or other major failures. The few service troubles which have arisen, in nearly all cases, have been concerned with the operation of auxiliary equipment, and further development work is actively in progress on these items, in conjunction with the specialist manufacturers concerned, where necessary. The paper ends with an assessment of likely future trends in the application of medium-power gas turbines. Attention is given to the integration of the turbine with packaged assisted circulation boilers in order to provide compactness and flexibility of output.
Gas Turbines in the Arabian Desert
Authors: Locher W. E. , Olson A. E. , Nibley P. P.
Published: May 2015

No men within 50 miles: But Tapline’s portable, radio-controlled, gas-turbine pumping units move oil across Saudi Arabia. The investment: One sixth that of a community-type station in that barren desert.
Operating Experience With Gas-Turbine Ships of the Maritime Administration
Authors: Tangerini C. C. , Specht D. H.
Published: May 2015

The two year operating results of the open cycle-gas turbine propulsion plant in the John Sergeant are given with reference to the actual performance, economy, and durability of the components of this marine drive. The operational records show that this type engine can compete favorably with conventional propulsion systems. Similarly, the operating results of the free piston gas-turbine propulsion plant in the William Patterson are given with limited operational experience at this time. The free-piston-installation operating record is submitted as preliminary.
Summary of Design Studies of a 250-HP Gas-Turbine Engine
Authors: Spooner S. H.
Published: May 2015

A summary is presented of studies performed by four engine manufacturers to determine the feasibility of developing a free-shaft gas-turbine engine of 250 hp for use in future Army aircraft and to provide a basis for establishing engine specifications for use in a design competition for such an engine.
Description and Service Experience of Various Boeing Gas-Turbine Marine Applications
Authors: Yeager V. A.
Published: May 2015

This paper gives a brief description of the Boeing small gas-turbine engine and describes the various marine applications, both propulsion and auxiliary, in which these engines have served. A discussion is included concerning the major problems and corrective action associated with the initial marine service of the latest production model engine, the 502-10C. The paper concludes with a summary of service analysis data of the 502-10C engine in marine applications.