bluuebunny/crossref_metadata_2025_split huggingface dataset:
The evolution of C4photosynthesis
Authors: Sage Rowan F. 
Published: December 2004

SummaryC4photosynthesis is a series of anatomical and biochemical modifications that concentrate CO2around the carboxylating enzyme Rubisco, thereby increasing photosynthetic efficiency in conditions promoting high rates of photorespiration. The C4pathway independently evolved over 45 times in 19 families of angiosperms, and thus represents one of the most convergent of evolutionary phenomena. Most origins of C4photosynthesis occurred in the dicots, with at least 30 lineages. C4photosynthesis first arose in grasses, probably during the Oligocene epoch (24–35 million yr ago). The earliest C4dicots are likely members of the Chenopodiaceae dating back 15–21 million yr; however, most C4dicot lineages are estimated to have appeared relatively recently, perhaps less than 5 million yr ago. C4photosynthesis in the dicots originated in arid regions of low latitude, implicating combined effects of heat, drought and/or salinity as important conditions promoting C4evolution. Low atmospheric CO2is a significant contributing factor, because it is required for high rates of photorespiration. Consistently, the appearance of C4plants in the evolutionary record coincides with periods of increasing global aridification and declining atmospheric CO2. Gene duplication followed by neo‐ and nonfunctionalization are the leading mechanisms for creating C4genomes, with selection for carbon conservation traits under conditions promoting high photorespiration being the ultimate factor behind the origin of C4photosynthesis.ContentsSummary341I.Introduction342II.What is C4photosynthesis?343III.Why did C4photosynthesis evolve?347IV.Evolutionary lineages of C4photosynthesis348V.Where did C4photosynthesis evolve?350VI.How did C4photosynthesis evolve?352VII.Molecular evolution of C4photosynthesis361VIII.When did C4photosynthesis evolve362IX.The rise of C4photosynthesis in relation to climate and CO2363X.Final thoughts: the future evolution of C4photosynthesis365Acknowledgements365References365
A 6‐month follow‐up of successful refits from daily disposable soft contact lenses to continuous wear of high‐Dk silicone‐hydrogel lenses
Authors: Aakre Bente Monica , Ystenaes Ann E. , Doughty Michael J. , Austrheim Øyvind , Westerfjell Björn , Lie Monica T. 
Published: December 2004

AbstractPurpose:  To compare, in routine optometric practice, the outcome of keeping successful soft contact lens (SCL) wearers in their lenses to re‐fitting them with continuous wear of silicone hydrogel (SiH) lenses.Methods:  Forty‐nine successful daily disposable lens wearers were recruited; 19 continued to wear daily SCLs and 30 were refitted with high‐Dk SiH lenses on a 30‐day/night schedule. Patients were assessed at baseline, 3 and 6 months by slit lamp examination along with the Efron grading scales, and central corneal thickness (CCT) and the corneal endothelium were assessed by non‐contact specular microscopy.Results:  No substantial changes in subjective vision, refraction, visual acuity or overall lens comfort occurred for those completing the study, although five SiH lens wearers did discontinue due to reduced comfort, eyelid problems or seasonal allergy. Contact lens induced peripheral ulcers (CLPU) were observed in three patients in the first 3 months in the SiH lens group and these were also discontinued. Over the 6 month period, a complete set of records was obtained for 16 in each group. For those completing the study, lens dryness scores were variable, but there was a slight improvement in favour of SiH lenses. Small, but statistically significant, reductions in corneal staining, bulbar hyperaemia, and limbal neovascularisation in favour of the SiH lenses were also evident but mainly because of further increases in the daily lens wearers. Contact lens induced papillary conjunctivitis (CLPC) and corneal endothelial polymegethism were mild to moderate and showed slight increases in the daily lens wearers at 6 months.Conclusions:  The present studies confirm that the continuous wear of SiH lenses for up to 30 days can be considered as an alternative to daily disposable soft lens wear, but is not suitable for everyone.
The optometric correlates of migraine
Authors: Harle Deacon E. , Evans Bruce J. W. 
Published: December 2004

AbstractMigraine is a common, chronic, multi‐factorial, neuro‐vascular disorder typically characterised by recurrent attacks of unilateral, pulsating headache and autonomic nervous system dysfunction. Migraine may additionally be associated with aura; those focal neurological symptoms that may precede or sometimes accompany the headache. This review describes the optometric aspects of migraine headache. There have been claims of a relationship between migraine headaches and errors of refraction, binocular vision anomalies, pupil anomalies, visual field changes and pattern glare. The quality of the evidence for a relationship between errors of refraction and binocular vision and migraine is poor. The quality of the evidence to suggest a relationship between migraine headache and pupil anomalies, visual field defects and pattern glare is stronger. In particular the link between migraine headache and pattern glare is striking. The therapeutic use of precision‐tinted spectacles to reduce pattern glare (visual stress) and to help some migraine sufferers is described.
The Effect of Dementia on Outcomes and Process of Care for Medicare Beneficiaries Admitted with Acute Myocardial Infarction
Authors: Sloan Frank A. , Trogdon Justin G. , Curtis Lesley H. , Schulman Kevin A. 
Published: December 2004

Objectives: To determine differences in mortality after admission for acute myocardial infarction (AMI) and in use of noninvasive and invasive treatments for AMI between patients with and without dementia.Design: Retrospective chart review.Setting: Cooperative Cardiovascular Project.Patients: Medicare patients admitted for AMI (N=129,092) in 1994 and 1995.Measurements: Dementia noted on medical chart as history of dementia, Alzheimer's disease, chronic confusion, or senility. Outcome measures included mortality at 30 days and 1‐year postadmission; use of aspirin, beta‐blocker, angiotensin‐converting enzyme (ACE) inhibitor, thrombolytic therapy, cardiac catheterization, coronary angioplasty, and cardiac bypass surgery compared by dementia status.Results: Dementia was associated with higher mortality at 30 days (relative risk (RR)=1.16, 95% confidence interval (CI)=1.09–1.22) and at 1‐year postadmission (RR=1.18, 95% CI=1.13–1.23). There were few to no differences in the use of aspirin and beta‐blockers between patients with and without a history of dementia. Patients with a history of dementia were less likely to receive ACE inhibitors during the stay (RR=0.89, 95% CI=0.86–0.93) or at discharge (RR=0.90, 95% CI=0.86–0.95), thrombolytic therapy (RR=0.82, 95% CI=0.74–0.90), catheterization (RR=0.51, 95% CI=0.47–0.55), coronary angioplasty (RR=0.58, 95% CI=0.51–0.66), and cardiac bypass surgery (RR=0.41, 95% CI=0.33–0.50) than patients without a history of dementia.Conclusion: The results imply that the presence of dementia had a major effect on mortality and care patterns for this condition.
Is Chronic Nonmalignant Pain Associated with Decreased Appetite in Older Adults? Preliminary Evidence
Authors: Bosley Brooke N. , Weiner Debra K. , Rudy Thomas E. , Granieri Evelyn 
Published: December 2004

Objectives: To examine the association between self‐reported appetite impairment and pain intensity in community‐dwelling older adults with chronic nonmalignant pain.Design: Cross‐sectional survey.Setting: An outpatient pain clinic at the University of Pittsburgh.Participants: A convenience sample of 65 older adults with chronic nonmalignant pain.Measurements: Demographics, pain intensity (short‐form McGill Pain Questionnaire), self‐reported appetite impairment using a newly developed instrument, mood (30‐item Geriatric Depression Scale, (GDS)), cognitive status (Folstein Mini‐Mental State Examination), dependence in feeding, dependence in grocery shopping and meal preparation, and comorbidities (Cumulative Illness Rating Scale). Medication information was classified as total number of medications, number of analgesics, number of opioids, and number of potential appetite‐impairing side effects.Results: Univariate analyses revealed that those who reported pain‐related appetite impairment had higher pain intensity than those who reported no appetite impairment (P<.001). Comparison of subjects with and without pain‐related appetite impairment revealed a significant difference in GDS scores (P=.027), number of analgesics (P=.015), and number of opioids (P=.014). None of the other variables was statistically significant. The relationship between pain intensity and perceived pain‐related appetite impairment was maintained in an analysis of covariance that controlled for GDS score, number of analgesics, and presence of opioids (P=.004).Conclusion: Chronic pain is associated with self‐reported appetite impairment in older adults, but examination of the influence of reduction in pain intensity on appetite improvement is needed to establish a causal relationship between chronic pain and diminished appetite.
Resilience of Community‐Dwelling Older Persons
Authors: Hardy Susan E. , Concato John , Gill Thomas M. 
Published: December 2004

Objectives:  To assess resilience of community‐dwelling older persons using a new scale based on response to a stressful life event and to identify the demographic, clinical, functional, and psychosocial factors associated with high resilience.Design:  Cross‐sectional study.Setting:  Community.Participants:  Five hundred forty‐six nondisabled persons aged 70 and older who had experienced a stressful life event.Measurements:  Resilience (as assessed using a simple six‐item scale), demographic factors, chronic conditions, medications, cognitive status, grip strength, functional status, physical activity, self‐efficacy, depressive symptoms, self‐rated health, and social support.Results:  Participants showed a wide range of resilience in response to a stressful event, with a mean score±standard deviation of 8.9±4.0 on an 18‐point scale. In bivariate analyses, male sex, living with others, high grip strength, independence in instrumental activities of daily living (IADLs), having few depressive symptoms, and having good to excellent self‐rated health were associated with high resilience, defined as a score in the best tertile (>10). Independence in IADLs (relative risk (RR)=1.36, 95% confidence interval (CI)=1.05–1.69), having few depressive symptoms (RR=1.59, 95% CI=1.13–2.11), and good to excellent self‐rated health (RR=1.38, 95% CI=1.01–1.79) remained independently associated with high resilience in multivariate analysis. Depressive symptoms and self‐rated health remained associated with high resilience after controlling for the perceived stressfulness of the event.Conclusion:  Functional and psychosocial factors are associated with high resilience. Further research is needed to determine the relationship between resilience and future well‐being.
The Identification of Seniors At Risk Screening Tool: Further Evidence of Concurrent and Predictive Validity
Authors: Dendukuri Nandini , McCusker Jane , Belzile Eric 
Published: December 2004

Objectives: To evaluate the validity of the Identification of Seniors at Risk (ISAR) screening tool for detecting severe functional impairment and depression and predicting increased depressive symptoms and increased utilization of health services.Setting: Four university‐affiliated hospitals in Montreal.Design: Data from two previous studies were available: Study 1, in which the ISAR scale was developed (n=1,122), and Study 2, in which it was used to identify patients for a randomized trial of a nursing intervention (n=1,889 with administrative data, of which 520 also had clinical data).Participants: Patients aged 65 and older who were to be released from an emergency department (ED).Measurements: Baseline validation criteria included premorbid functional status in both studies and depression in Study 2 only. Increase in depressive symptoms at 4‐month follow‐up was assessed in Study 2. Information on health services utilization during the 5 months after the ED visit (repeat ED visits and hospitalization in both studies, visits to community health centers in Study 2) was available by linkage with administrative databases.Results: Estimates of the area under the receiver operating characteristic curve (AUC) for concurrent validity of the ISAR scale for severe functional impairment and depression ranged from 0.65 to 0.86. Estimates of the AUC for predictive validity for increased depressive symptoms and high utilization of health services ranged from 0.61 to 0.71.Conclusion: The ISAR scale has acceptable to excellent concurrent and predictive validity for a variety of outcomes, including clinical measures and utilization of health services.
Predictors of Adherence to the Use of Hip Protectors in Nursing Home Residents
Authors: Warnke Andrea , Meyer Gabriele , Bender Ralf , Mühlhauser Ingrid 
Published: December 2004

Objectives: To assess predictors of hip‐protector use in nursing home residents under usual‐care conditions and after intervention consisting of structured education of nurses and nursing home residents and provision of free hip protectors.Design: Nested cohort analyses within a cluster randomized, controlled trial with 18 months follow‐up.Setting: Forty‐nine nursing home clusters in Hamburg, Germany.Participants: Residents with at least one fall during the study period (intervention group, n=237; usual‐care group, n=274).Measurements: Use of hip protector while falling. Regression analyses were performed for each of the two cohorts of fallers using the time to the first fall without hip protector as the dependent variable. Predefined nursing home cluster‐related parameters (center, staffing ratio, proportion of registered nurses in nursing staff, hip‐protector use before study period) and resident‐related parameters (sex, history of falls and fractures, fear of falling, urinary incontinence, use of walking aid, degree of disablement) were considered as explanatory variables.Results: Under usual care, 97% of fallers (n=266), compared with 62% (n=148) in the intervention group, experienced at least one fall without hip protection. Using Cox proportional hazards models with and without frailty parameter (random cluster effect), the following predictors were identified: intervention group: use of walking aid, hazard ratio (HR)=1.53 (95% confidence interval (CI):0.98–2.39) and no urinary incontinence, HR=1.47 (95% CI:1.03–2.09); usual care: nursing staff per 10 residents, HR=0.78 (95% CI=0.63–0.96); high degree of disablement, HR=1.38 (95% CI=1.06–1.80); strong fear of falling, HR=0.78 (95% CI=0.60–1.02). The nursing home cluster was a significant predictor in the control group (P=.029), but not in the intervention group (P=.100).Conclusion:  Only a few and weak predictors of hip‐protector use of questionable relevance could be identified in both groups. Future research should concentrate on the implementation of interventions of proven efficacy, such as provision of hip protectors combined with structured education of staff and residents.
Effect of Widowhood on Disability Onset in Elderly Men from Three European Countries
Authors: Van Den Brink Carolien L. , Tijhuis Marja , Van Den Bos Geertrudis A.M. , Giampaoli Simona , Kivinen Paula , Nissinen Aulikki , Kromhout Daan 
Published: December 2004

Objectives: To investigate in different countries the effects of becoming widowed, duration of widowhood, and household composition of widowed men on disability onset in different disability domains.Design: Longitudinal data from a cohort study collected around 1990, 1995, and 2000.Setting: Three cohorts from Finland, the Netherlands, and Italy.Participants: Seven hundred thirty‐six men, aged 70 and older at baseline.Measurements: Disability was measured using standardized questionnaire on activities of daily living (ADLs). Three domains were assessed: instrumental ADLs (IADLs), mobility, and basic ADLs (BADLs). Duration of widowhood was divided into less than 5 years and 5 or more years and household composition into living alone and living with family or in an institution.Results: Men who became widowed developed more IADL disabilities (odds ratio (OR)=2.15; 95% confidence interval (CI)=1.22–3.81) and mobility (OR=1.84; 95% CI=1.15–2.96) than men who were still married. Men who had been widowed for less than 5 years developed more IADL disabilities than those who had been widowed for 5 years or more (OR=2.27; 95% CI=1.14–4.54). Widowed men living alone showed fewer disabilities in mobility (OR=0.25; 95% CI=0.09–0.73) and BADLs (OR=0.02; 95% CI=0.001–0.33) than those living with others. The effects on disability onset did not differ between countries.Conclusion: Widowhood in elderly men is a risk factor for dependency in IADLs and mobility. The growth in the number of widowers may lead to higher demands on family care and professional care.
The National Pressure Ulcer Long‐Term Care Study: Pressure Ulcer Development in Long‐Term Care Residents
Authors: Horn Susan D. , Bender Stacy A. , Ferguson Maree L. , Smout Randall J. , Bergstrom Nancy , Taler George , Cook Abby S. , Sharkey Siobhan S. , Voss Anne Coble 
Published: December 2004

Objectives: To identify resident, treatment, and facility characteristics associated with pressure ulcer (PU) development in long‐term care residents.Design: Retrospective cohort study with convenience sampling.Setting: Ninety‐five long‐term care facilities participating in the National Pressure Ulcer Long‐Term Care Study throughout the United States.Participants: A total of 1,524 residents aged 18 and older, with length of stay of 14 days or longer, who did not have an existing PU but were at risk of developing a PU, as defined by a Braden Scale for Predicting Pressure Sore Risk score of 17 or less, on study entry.Measurements: Data collected for each resident over a 12‐week period included resident characteristics (e.g., demographics, medical history, severity of illness using the Comprehensive Severity Index, Braden Scale scores, nutritional factors), treatment characteristics (nutritional interventions, pressure management strategies, incontinence treatments, medications), staffing ratios and other facility characteristics, and outcome (PU development during study period). Data were obtained from medical records, Minimum Data Set, and other written records (e.g., physician orders, medication logs).Results: Seventy‐one percent of subjects (n=1,081) did not develop a PU during the 12‐week study period; the remaining 29% of residents (n=443) developed a new PU. Resident, treatment, and facility characteristics associated with greater likelihood of developing a Stage I to IV PU included higher initial severity of illness, history of recent PU, significant weight loss, oral eating problems, use of catheters, and use of positioning devices. Characteristics associated with decreased likelihood of developing a Stage I to IV PU included new resident, nutritional intervention (e.g., use of oral medical nutritional supplements and tube feeding for >21 days), antidepressant use, use of disposable briefs for more than 14 days, registered nurse hours of 0.25 hours per resident per day or more, nurses' aide hours of 2 hours per resident per day or more, and licensed practical nurse turnover rate of less than 25%. When Stage I PUs were excluded from the analyses, the same variables were significant, with the addition of fluid orders associated with decreased likelihood of developing a PU.Conclusion: A broad range of factors, including nutritional interventions, fluid orders, medications, and staffing patterns, are associated with prevention of PUs in long‐term care residents. Research‐based PU prevention protocols need to be developed that include these factors and target interventions for reducing risk factors.
Large‐Artery Stiffness Contributes to the Greater Prevalence of Systolic Hypertension in Elderly Women
Authors: Berry Karen L. , Cameron James D. , Dart Anthony M. , Dewar Elizabeth M. , Gatzka Christoph D. , Jennings Garry L. , Liang Yu‐Lu , Reid Chris M. , Kingwell Bronwyn A. 
Published: December 2004

Objectives: To determine whether sex differences in large‐artery stiffness contribute to the greater prevalence of systolic hypertension in elderly women than in elderly men.Design: During a single visit arterial stiffness was assessed in the unmedicated state using four parameters.Participants: Three hundred seventy‐four women with a mean age±standard deviation of 72±5 and 296 men aged 71±5 participated.Setting: Hypertensive patients were recruited from general practice as part of the second Australian National Blood Pressure Study in Melbourne, Australia.Measurements: Large‐artery stiffness was assessed using multiple methodologies, including aortic arch stiffness (β‐index) using M‐mode ultrasound and arterial compliance and augmentation index using noninvasive carotid pressure and aortic flow measurements.Results: Women had greater carotid and brachial pulse pressure (PP) than men (P<.001), despite higher mean arterial pressure in men. Mean arterial compliance was lower in women (0.20±0.12 vs 0.28±0.16 mL/mmHg, P<.001) even after correction for aortic area, and aortic arch stiffness was higher (30±36 vs 23±22; P<.01). Consistent with both a stiffer proximal circulation and a shorter distance to reflection sites, women had higher augmentation index (38±11% vs 29±12%, P<.001). In multivariate analysis, sex was an independent determinant of all arterial stiffness indices.Conclusion: Independently of known confounders, elderly hypertensive women have stiffer large arteries, greater central wave reflection, and higher PP than elderly men. Stiffer large arteries likely contribute to the greater prevalence of systolic hypertension in elderly women and may partly explain the acceleration in postmenopausal cerebrovascular and cardiac complications.
Effect of State Medicaid Reimbursement Rates on Hospitalizations from Nursing Homes
Authors: Intrator Orna , Mor Vincent 
Published: December 2004

Objectives: To estimate the effect of state Medicaid nursing home reimbursement rates on hospitalizations of nursing home residents.Design: Cross‐sectional sample of nongovernment‐owned nursing homes with 25 beds or more in one Metropolitan Statistical Area in each of 10 states in 1993, with 6 months follow‐up on mortality and hospitalizations.Setting: Two hundred fifty‐three nursing homes.Participants: Eight to 16 randomly selected residents from each facility, totaling 2,080.Measurements: Minimum Data Set assessments conducted by research nurses at baseline. A three‐category 6‐month outcome was defined as (1) any hospitalization; for those not hospitalized, (2) death versus (3) alive in the facility.Results: Using multinomial logistic regression, adjusted to survey design, controlling for resident and facility characteristics, a $10 increase in 1993 Medicaid reimbursement rate above the mean rate of approximately $75 resulted in a 9% reduction in a resident's risk of hospitalization (P<.05).Conclusion: State Medicaid reimbursement rates appear to affect clinical decisions regarding the need for hospital admission and thresholds for nursing home use. The findings from this study reemphasize the importance of properly aligning state Medicaid and federal Medicare long‐term care policies because, currently, states have no incentive to increase reimbursement rates to avoid hospitalization.