bluuebunny/crossref_metadata_2025_split huggingface dataset:
Monazite geochronology in central New England: evidence for a fundamental terrane boundary
Authors: SPEAR F. S. , CHENEY J. T. , PYLE J. M. , HARRISON T. M. , LAYNE G. 
Published: January 2008

AbstractMonazite crystallization ages have been measured in situ using SIMS and EMP analysis of samples from the Bronson Hill anticlinorium in central New England. In west‐central New Hampshire, each major tectonic unit (nappe) displays a distinctive P–T path and metamorphic history that requires significant post‐metamorphic faulting to place them in their current juxtaposition, and monazite ages were determined to constrain the timing of metamorphism and nappe assembly. Monazite ages from the low‐pressure, high‐temperature Fall Mountain nappe range from c. 455 to 355 Ma, and Y zoning indicates that these ages comprise three to four distinct age domains, similar to that found in the overlying Chesham Pond nappe. The underlying Skitchewaug nappe contains monazite ages that range from c. 417 to 307 Ma. 40Ar/39Ar ages indicate rapid cooling of the Chesham Pond and Fall Mountain nappes after 350 Ma, which is believed to represent the time of emplacement of the high‐level Chesham Pond and Fall Mountain nappes onto rocks of the underlying Skitchewaug nappe. Garnet zone rocks from western New Hampshire contain monazite that display a range of ages (c. 430–340 Ma). Both the metamorphic style and monazite ages suggest that the low‐grade belt in western New Hampshire is continuous with the Vermont sequence to the west. Rocks of the Big Staurolite nappe in western New Hampshire contain monazite that crystallized between c. 370 and 290 Ma and the same unit along strike in northern New Hampshire and central Connecticut records ages of c. 257–300 Ma. Conspicuously absent from this nappe are the older age populations that are found in both the overlying nappes and underlying garnet zone rocks. These monazite ages confirm that the metamorphism observed in the Big Staurolite nappe occurred significantly later than that in the units structurally above and below. These data support the hypothesis that the Big Staurolite nappe represents a major tectonic boundary, along which rocks of the New Hampshire metamorphic series were juxtaposed against rocks of the Vermont series during the Alleghanian.
Efficacy of the ketogenic diet in the 6‐Hz seizure test
Authors: Hartman Adam L. , Lyle Megan , Rogawski Michael A. , Gasior Maciej 
Published: January 2008

Summary
Purpose: Since the ketogenic diet is effective in drug‐resistant epilepsies, we sought to determine whether it is active in the 6‐Hz seizure test, which identifies agents with a broader spectrum of activity than conventional antiepileptic screening tests.
Methods: Male (3–4 week old) NIH Swiss mice were fed a normal or ketogenic diet ad libitum for 2–21 days. The intensity of the corneal stimulation current required to elicit seizures in the 6‐Hz test was measured. Blood glucose and β‐hydroxybutyrate were measured on the day of seizure testing.
Results: CC50 (current intensity producing seizures in 50% of mice tested) was 50.6 mA and 15 mA in mice fed for 12 days with a ketogenic or normal diet, respectively (p < 0.001). CC50 was elevated in separate experiments after 16, but not 2, 5, and 21 days of ketogenic diet exposure. CC50 values of growing mice fed the normal diet does not differ, indicating CC50 does not vary with mouse weight during a rapid growth phase. β‐Hydroxybutyrate was significantly higher, and glucose was significantly lower in mice fed the ketogenic diet than those fed the normal diet. Blood glucose and β‐hydroxybutyrate levels did not correlate with CC50.
Discussion: The ketogenic diet significantly elevates the seizure threshold in the 6‐Hz test in a time‐specific manner. Protection from seizures in this model was not related to level of ketosis. CC50 was insensitive to body weight in mice fed the normal diet, demonstrating that the 6‐Hz model can assess anticonvulsant regimens where weight is a confounding factor.
Unhealthy Drinking Patterns in Older Adults: Prevalence and Associated Characteristics
Authors: Merrick Elizabeth L. , Horgan Constance M. , Hodgkin Dominic , Garnick Deborah W. , Houghton Susan F. , Panas Lee , Saitz Richard , Blow Frederic C. 
Published: January 2008

OBJECTIVES: To examine the prevalence of unhealthy drinking patterns in community‐dwelling older adults and its association with sociodemographic and health characteristics.DESIGN: Cross‐sectional analysis of nationally representative survey data.SETTING: The data source was the 2003 Access to Care file of the Medicare Current Beneficiary Survey, which represents the continuously enrolled Medicare population.PARTICIPANTS: Community‐dwelling Medicare beneficiaries aged 65 and older (N=12,413).MEASUREMENTS: The prevalence of unhealthy alcohol use by older adults defined in relation to two parameters of recommended limits: monthly use exceeding 30 drinks per typical month and “heavy episodic” drinking of four or more drinks in any single day during a typical month in the previous year. Sociodemographic and health status variables were also included.RESULTS: Nine percent of elderly Medicare beneficiaries reported unhealthy drinking, with higher prevalence in men (16%) than women (4%). In logistic regression analyses with the full sample, higher education and income; better health status; male sex; younger age; smoking; being white; and being divorced, separated, or single were associated with higher likelihood of unhealthy drinking. Among drinkers, in addition to sociodemographic variables, self‐reported depressive symptoms were positively associated with unhealthy drinking. Among unhealthy drinkers, race and ethnicity variables were associated with likelihood of heavy episodic drinking.CONCLUSION: Almost one in 10 elderly Medicare beneficiaries report exceeding recommended drinking limits. Several distinct unhealthy drinking patterns were identified and associated with sociodemographic and health characteristics, suggesting the value of additional targeted approaches within the context of universal screening to reduce alcohol misuse by older adults.
The Effect of Obstructive Sleep Apnea on Morbidity and Health Care Utilization of Middle‐Aged and Older Adults
Authors: Tarasiuk Ariel , Greenberg‐Dotan Sari , Simon‐Tuval Tzahit , Oksenberg Arie , Reuveni Haim 
Published: January 2008

OBJECTIVES: To determine whether elderly subjects with obstructive sleep apnea (OSA) had different morbidity and health care utilization than elderly subjects without OSA and middle‐aged patients with OSA 2 years before diagnosis.DESIGN: Case‐control study between January 2001 and April 2003.SETTING: Two sleep–wake disorders centers.PARTICIPANTS: One hundred fifty‐eight elderly and 1,166 middle‐aged (aged 67–89 and 40–64, respectively) patients with OSA were matched 1:1 with healthy controls according to age, sex, geographic area, and primary physician.MEASUREMENTS: Polysomnography, medical diagnoses, and healthcare utilization.RESULTS: Healthcare costs 2 years before diagnosis were more than 1.8 times as high for elderly and middle‐aged patients with OSA as for controls (P<.001). Expenditures of elderly patients with OSA were 1.9 times as high as for middle‐aged patients with OSA (P<.001). Multiple logistic regression analysis (adjusting for age, body mass index, and apnea hypopnea index) revealed that cardiovascular disease (CVD) (odds ratio (OR)=4.1, 95% confidence interval (CI)=1.8–9.3) and use of psychoactive drugs (OR=3.8, 95% CI=1.5–10.1) are independent determinants for the top‐third most‐costly elderly patients with OSA.CONCLUSION: Elderly patients with OSA have high healthcare utilization because of CVD morbidity and use of psychoactive medications. Therefore, OSA has clinical significance in elderly people.
Risk Factors for Deep Vein Thrombosis in Older Patients: A Multicenter Study with Systematic Compression Ultrasonography in Postacute Care Facilities in France
Authors: Sellier Elodie , Labarere Jose , Sevestre Marie‐Antoinette , Belmin Joel , Thiel Helene , Couturier Pascal , Bosson Jean‐Luc ,   for the Association pour la Promotion de l'Angiologie Hospitalière
Published: January 2008

OBJECTIVES: To identify risk factors for deep vein thrombosis (DVT) in older patients with restricted mobility or functional disability.DESIGN: Cross‐sectional.SETTING: Forty‐two postacute care departments in France.PARTICIPANTS: Eight hundred twelve patients aged 65 and older.MEASUREMENTS: Twenty‐two predefined characteristics were investigated, including medical and surgical risk factors, dependence in six basic activities of daily living (ADLs) rated using the Katz index, mobility, the reported value of the Timed Up and Go Test, and pressure ulcers. All patients underwent lower limb ultrasonography on the day of the cross‐sectional study.RESULTS: DVT was found in 113 patients (14%, 33 proximal DVTs (4%) and 80 isolated distal DVTs (10%)). A positive trend was found in the odds of DVT for higher values on the Timed Up and Go Test for patients who were not bedridden or confined to a chair (P=.007). In two‐level multivariable analysis adjusting for prophylaxis against venous thromboembolism, independent risk factors for DVT were aged 80 and older (adjusted odds ratio (aOR)=1.71, 95% confidence interval (CI)=1.05–2.79), previous history of venous thromboembolism (aOR=2.03, 95% CI=1.06–3.87), regional or metastatic‐stage cancer (aOR=2.71, 95% CI=1.27–5.78), dependence in more than three ADLs (aOR=2.18, 95% CI=1.38–3.45), and pressure ulcers (aOR=1.85, 95% CI=1.05–3.24).CONCLUSION: Severe dependence in basic ADLs and higher Timed Up and Go Test score are associated with greater odds of DVT in older patients in postacute care facilities in France.
Medical Student Attitudes Toward Older People and Willingness to Consider a Career in Geriatric Medicine
Authors: Hughes Niall J. , Soiza Roy L. , Chua Melvin , Hoyle Graeme E. , MacDonald Allan , Primrose William R. , Gwyn Seymour D. 
Published: January 2008

OBJECTIVES: To evaluate the attitudes of first‐ and fourth‐year medical students toward older people and the relationship between these attitudes and possible career choice. To examine the effects of an intensive geriatric medicine (GM) teaching program on these attitudes and career aspirations.DESIGN: Observational study.SETTING: University of Aberdeen.PARTICIPANTS: Medical students.MEASUREMENTS: In September 2005, first‐year students (n=163) at the start of their undergraduate training completed a questionnaire based on the University of California at Los Angeles Geriatrics Attitudes Scale. Students were asked how likely they were to consider a career in GM in the future on a 5‐point Likert scale. From the beginning of the academic year 2005/06, fourth‐year students completed the same questionnaire before and after an intensive 8‐day GM teaching program.RESULTS: First‐year medical students had a mean attitude score±standard deviation of 3.69±0.39. A more‐positive attitude increased the likelihood of considering a career in GM (P<.001). Fourth‐year students had better attitude scores than first‐year students (3.86±0.36, P=.002). The GM teaching program did not significantly affect attitude scores but significantly increased the willingness to consider a career in GM by a mean 0.52 points (95% confidence interval=0.35–0.70, P<.001).CONCLUSION: Attitudes toward older people were better in fourth‐year than first‐year medical students. A more‐positive attitude toward older people increased the likelihood of considering a career in GM. An intensive 8‐day course in GM had no significant effect on attitudes but increased the likelihood of fourth‐year students considering a career in GM.
Higher Levels of Inflammation Factors and Greater Insulin Resistance Are Independently Associated with Higher Heart Rate and Lower Heart Rate Variability in Normoglycemic Older Individuals: The Cardiovascular Health Study
Authors: Stein Phyllis K. , Barzilay Joshua I. , Chaves Paulo H. M. , Traber Jennifer , Domitrovich Peter P. , Heckbert Susan R. , Gottdiener John S. 
Published: January 2008

OBJECTIVES: To explore the relationship between (1) insulin resistance and inflammation factors with (2) higher heart rate (HR) and lower heart rate variability (HRV) in normoglycemic older adults.DESIGN: Cross‐sectional population‐based study.PARTICIPANTS: Five hundred forty‐five adults aged 65 and older with normoglycemia (fasting glucose <100 mg/dL) who participated in the Cardiovascular Health Study.MEASUREMENTS: Serum levels of three inflammation proteins (C‐reactive protein (CRP), interleukin 6 (IL‐6), and fibrinogen); insulin resistance, quantified according to the homeostasis assessment model (HOMA‐IR); HR; and four representative measures of HRV (the standard deviation of normal beat to beat intervals (SDNN), the root mean square of successive differences (rMSSD), very low frequency power (VLF), and the low‐ to high‐frequency power ratio (LF/HF)) derived from 24‐hour Holter recordings.RESULTS: High CRP and IL‐6 levels were associated with higher HR and lower SDNN and VLF after adjustment for multiple covariates, including HOMA‐IR and clinical cardiovascular disease. High IL‐6 was also associated with lower LF/HF. Significant univariate inverse relationships between HOMA‐IR and HR and HRV were also found, but the strengths of these relationships were attenuated after adjustment for inflammation factors.CONCLUSION: Increased levels of inflammation markers and HOMA‐IR are associated with higher HR and lower HRV. These findings suggest that inflammation may contribute to the pathogenesis of cardiovascular autonomic decline in older adults.
Security Concentration and Active Fund Management: Do Focused Funds Offer Superior Performance?
Authors: Sapp Travis , Yan Xuemin (Sterling) 
Published: January 2008

AbstractWe examine gross fund returns based on the number of securities held and find no evidence that focused funds outperform diversified funds. After deducting expenses, focused funds significantly underperform. Controlling for various fund characteristics, fund performance is positively related to the fund's number of holdings both before and after expenses. We find evidence linking focused fund underperformance to agency and liquidity problems. Finally, the attrition rate of focused funds is higher than that of diversified funds. These results do not support the view that managers holding focused portfolios have superior stock‐picking skills or that focused funds provide value to investors.
Emerging Market Bond Funds: A Comprehensive Analysis
Authors: Polwitoon Sirapat , Tawatnuntachai Oranee 
Published: January 2008

AbstractWe analyze U.S.‐based emerging market bond funds over a ten‐year (1996–2005) complete cycle of ups and downs in the dominant emerging bond markets. Emerging market bond funds outperform comparable domestic and global bond funds. The results are robust across both conditional and unconditional models. The funds also provide international diversification benefits to U.S. and international bond and equity portfolios. The funds exhibit persistence in performance and seasonality. Active funds, large funds and funds with high minimum purchases perform better on a total return basis but not on a risk‐adjusted basis.
Dual Class IPOs ARE Underpriced Less Severely
Authors: Smart Scott B. , Zutter Chad J. 
Published: January 2008

AbstractWe analyze a sample of dual and single class initial public offerings (IPOs) to investigate whether empirical estimates of underpricing determinants are consistent across alternative measures of firm size and alternative techniques intended to account for underwriter price stabilization efforts. We find that results from long‐standing methods for estimating underpricing relations are generally robust to one's choice of size proxy and are consistent with estimates obtained from censored regressions of first‐day returns and from least squares regressions of longer horizon initial returns. We also confirm an existing finding in the literature that dual class IPOs endure less underpricing than do single class firms.
Central nervous system involvement after herpes zoster ophthalmicus
Authors: Haargaard Birgitte , Lund‐Andersen Henrik , Milea Dan 
Published: January 2008

Abstract.Purpose:  To report central nervous system involvement after varicella zoster virus infection.Methods:  We evaluated the frequency and type of neurological complications in patients initially presenting with ophthalmic herpes zoster at an ophthalmological department in a Danish university hospital, over a 7‐year period.Results:  Of the 110 immunocompetent patients who presented with initial ophthalmic zoster, six (5.5%) suffered from neurological complications other than post‐herpetic neuralgia. Four experienced isolated cranial motor nerve palsies, one patient had meningitis with a favourable outcome and one patient had severe encephalitis with a poor clinical outcome.Conclusions:  Central nervous system involvement after varicella zoster virus infection is an uncommon, but potentially life‐threatening, complication. Early recognition of neurological complications prompts acute, appropriate antiviral treatment.
Eye movements and binocular function in low birthweight teenagers
Authors: Lindqvist Susanne , Vik Torstein , Indredavik Marit S. , Skranes Jon , Brubakk Ann‐Mari 
Published: January 2008

Abstract.Purpose:  To assess eye movements and binocular function in 14‐year‐olds with very low birthweight (VLBW: birthweight ≤ 1500 g) and 14‐year‐olds born at term but small for gestational age (SGA: birthweight < 10th percentile) in a population‐based study.Methods:  Ophthalmological examinations including measurements of heterophoria/tropia, near point of convergence, accommodative amplitude, stereopsis, nystagmus, saccades and smooth pursuit were performed in 51 adolescents with VLBW, 58 adolescents born SGA and in a control group consisting of 75 subjects of the same age.Results:  Latent or manifest strabismus, poor stereopsis, poor convergence and nystagmus were all more frequent in the VLBW group than in the control group. The VLBW group did not differ from the control group regarding accommodative amplitude or saccades and smooth pursuit. The SGA population did not differ from the control group in the measured variables.Conclusions:  Premature birth with VLBW affects binocular visual functions negatively in adolescence, whereas birth small for date at term does not appear to be a risk factor for impaired eye movements and binocular function.
Bone regeneration of dental implant dehiscence defects using a cultured periosteum membrane
Authors: Mizuno Daiki , Kagami Hideaki , Mizuno Hirokazu , Mase Junji , Usami Kazutada , Ueda Minoru 
Published: January 2008

AbstractObjectives: This study aimed to demonstrate the feasibility of a cultured periosteum (CP) membrane for use in guided bone regeneration at sites of implant dehiscence.Material and methods: Four healthy beagle dogs were used in this study. Implant dehiscence defects (4 × 4 × 3 mm) were surgically created at mandibular premolar sites where premolars had been extracted 3 months back. Dental implants (3.75 mm in diameter and 7 mm in length) with machined surfaces were placed into the defect sites (14 implants in total). Each dehiscence defective implant was randomly assigned to one of the following two groups: (1) PRP gel without cells (control) or (2) a periosteum membrane cultured on PRP gel (experimental). Dogs were killed 12 weeks after operation and nondecalcified histological sections were made for histomorphometric analyses including percent linear bone fill (LF) and bone‐to‐implant contact (BIC).Results: Bone regeneration in the treatment group with a CP membrane was significantly greater than that in the control group and was confirmed by LF analysis. LF values in the experimental and the control groups were 72.36±3.14% and 37.03±4.63%, respectively (P<0.05). The BIC values in both groups were not significantly different from each other. The BIC values in the experimental and the control groups were 40.76±10.30% and 30.58±9.69%, respectively (P=0.25) and were similar to native bone.Conclusion: This study demonstrated the feasibility of a CP membrane to regenerate bone at implant dehiscence defect.
Bone apposition around two different sandblasted and acid‐etched titanium implant surfaces: a histomorphometric study in canine mandibles
Authors: Bornstein Michael M. , Valderrama Pilar , Jones Archie A. , Wilson Thomas G. , Seibl Reinhart , Cochran David L. 
Published: January 2008

AbstractPurpose: The aim of this study was to evaluate bone apposition to a modified sandblasted and acid‐etched (SLA) implant surface (modSLA) in the canine mandible as compared with the standard SLA surface.Material and methods: In this experimental study, all mandibular premolars and first molars were extracted bilaterally in five foxhounds. After a healing period of 6 months, each side of the mandible received six randomly assigned dental implants alternating between the standard SLA and modSLA surface. The dogs were sacrificed at 2 weeks (n=2) or 4 weeks (n=3) after implant placement. Histologic and histomorphometric analyses were then performed for each implant.Results: The microscopic healing patterns at weeks 2 and 4 for the two implant types with the standard SLA and modSLA surfaces showed similar qualitative findings. New bone tissue had already established direct contact with implant surfaces after 2 weeks of healing. The mean percentage of newly formed bone in contact with the implant (BIC) was significantly greater for modSLA (28.2±7.9%) than for SLA (22.2±7.3%) (P<0.05). This difference was no longer evident after 4 weeks. An increase in BIC for both implant surface types occurred from weeks 2 to 4. This increase was statistically significant when compared with SLA at 2 weeks (P<0.05), but not when compared with modSLA at 2 weeks.Conclusion: The data from the present study demonstrate significantly more bone apposition for the modSLA surface than the standard SLA surface after 2 weeks of healing. This increased bone apposition may allow a further reduction of the healing period following implant placement for patients undergoing early loading procedures.
Changes in the pre‐surgical treatment planning using conventional spiral tomography
Authors: Diniz Ana Flávia N. , Mendonça Elismauro F. , Leles Claudio R. , Guilherme Adérico S. , Cavalcante Marcelo P. , Silva Maria Alves G. S. 
Published: January 2008

AbstractObjective: To investigate variation in the pre‐surgical treatment planning after using conventional spiral tomography in addition to conventional radiographic exams.Material and methods: Twenty‐nine partial or fully edentulous patients referred to implant therapy were selected and submitted to periapical, panoramic and conventional cross‐sectional tomography exams. Pre‐surgical treatment planning of 120 potential implant sites in 69 edentulous areas was performed by two independent experienced dental implant surgeons. After clinical examination, pre‐surgical planning was made using only periapical and panoramic exams. Examiners were requested to reformulated initial planning after assessing tomographic images. Four treatment parameters were evaluated: length and width of implants, need of bone grafting and need of other surgical procedures.Results: Implant length and width remained unchanged in 60.2% and 87.2% of cases, respectively. No difference in length (P=0.576) and width (P=1) scores was observed in treatment planning with and without tomography. Variation in implant dimension was not affected by location of edentulous areas. Bone grafting and other surgical procedures significantly changed after tomograms (P<0.001), independent of the location of edentulous areas. In 15.8% and 5.3% of cases bone grafting and other procedures were planned only after tomograms, respectively. Significant differences were observed in all maxillary and mandibular regions.Conclusion: Conventional spiral tomography plays an important role in pre‐surgical treatment planning, increasing clinician's certainty of the need of additional surgical procedures (bone grafting, sinus lifting, and others) in pre‐surgical treatment stage.