bluuebunny/crossref_metadata_2025_split huggingface dataset:
Predictors of progression to severe Alzheimer's disease in an incidence sample
Authors: Rabins Peter V. , Schwartz Sarah , Black Betty S. , Corcoran Christopher , Fauth Elizabeth , Mielke Michele , Christensen Jessica , Lyketsos Constantine , Tschanz JoAnn 
Published: November 2012

BackgroundLittle is known about factors influencing time to severe Alzheimer's disease (AD).MethodsIncident cases of AD in the Cache County Memory Study were identified. Severe AD was defined as Mini‐Mental State Examination score of ≤10 or Clinical Dementia Rating Scale score of 3; cases with either Mini‐Mental State Examination score of ≥16 or Clinical Dementia Rating <2 were not categorized as severe AD. Kaplan–Meier, log‐rank tests, and Cox analyses were used to identify demographic, clinical, and genetic correlates of time to progression to severe AD.ResultsSixty‐eight of 335 cases of incident AD developed severe dementia. In bivariate analyses, female gender, less than high school education, at least one clinically significant Neuropsychiatric Inventory domain at baseline, and the youngest and oldest ages exhibited shorter time to severe AD. In competing risk analysis, subjects with mild or at least one clinically significant Neuropsychiatric Inventory domain score, and subjects with worse health were more likely to progress to severe dementia or death.ConclusionsDemographic and clinical variables predict progression to severe AD. Further study should examine whether these relationships are causal or correlational.
Cognitive and functional resilience despite molecular evidence of Alzheimer's disease pathology
Authors: Negash Selam , Xie Sharon , Davatzikos Christos , Clark Christopher M. , Trojanowski John Q. , Shaw Leslie M. , Wolk David A. , Arnold Steven E. 
Published: November 2012

AbstractBackgroundThe correlation between neuropathological lesions and cognition is modest. Some individuals remain cognitively intact despite the presence of significant Alzheimer's disease (AD) pathology, whereas others manifest cognitive symptoms and dementia in the same context. The aim of the present study was to examine cognitive and cerebral reserve factors associated with resilient functioning in the setting of AD pathology.MethodsUniversity of Pennsylvania Alzheimer's Disease Center research participants with biochemical biomarker evidence of AD pathology (cerebrospinal fluid amyloid‐β1‐42 <192 pg/mL) and comparable medial temporal lobe atrophy were categorized by Clinical Dementia Rating Scale‐Sum of Boxes (CDR‐SOB) score as AD dementia (CDR‐SOB >1) or AD resilient (CDR‐SOB ≤0.5). Groups were compared for a variety of demographic, clinical, and neuroimaging variables to identify factors that are associated with resilience to AD pathology.ResultsA univariate model identified education and intracranial volume (ICV) as significant covariates. In a multivariate model with backward selection procedure, ICV was retained as a factor most significantly associated with resilience. The interaction term between ICV and education was not significant, suggesting that larger cranial vault size is associated with resilience even in the absence of more education.ConclusionsPremorbid brain volume, as measured through ICV, provided protection against clinical manifestations of dementia despite evidence of significant accumulations of AD pathology. This finding provides support for the brain reserve hypothesis of resilience to AD.
Predictors and outcomes for caregivers of people with mild cognitive impairment: A systematic literature review
Authors: Seeher Katrin , Low Lee‐Fay , Reppermund Simone , Brodaty Henry 
Published: November 2012

AbstractBackgroundDementia caregiving is strongly linked to depression, anxiety, and burden in caregivers. Little is known about whether the same holds for people supporting an older person with mild cognitive impairment (MCI). We aim to systematically review the current evidence for negative caregiver outcomes in MCI using Pearlin and colleagues' stress process model as a theoretical framework.MethodsWidely used scientific literature databases were searched using MCI‐ and caregiver‐related terms with “AND” relations. Results were limited to quantitative English language articles published in peer‐reviewed journals between 1980 and November 2010.ResultsOf the 266 identified articles, six reported relevant depression data on 988 MCI caregivers (73% spouses). The pooled Center for Epidemiologic Studies Depression scale (CES‐D) mean score was 12.95 (standard deviation = 6.16). The pooled depression prevalence (i.e., CES‐D score ≥ 16 or equivalent) was 23%. Two studies compared depression in MCI and dementia caregivers, indicating higher levels in dementia caregivers. Other outcomes, such as burden, stress, or anxiety, were only investigated by individual studies precluding pooling of data. Similarly, pooling of the data on the predictors of caregiver outcomes was impossible because of data heterogeneity. However, descriptive analysis of predictors revealed that Pearlin and colleagues' caregiver stress process model at least partially applies to the MCI context.ConclusionsThe studies reviewed were all cross sectional in design, involving clinical samples, thus limiting generalizability. Depression and psychological comorbidity, although not as pronounced as in dementia caregivers, are common complications in MCI caregivers. The long‐term course of outcomes in MCI caregivers requires further investigation.
Effects of cultured human adipose‐derived stem cells transplantation on rabbit cornea regeneration after alkaline chemical burn
Authors: Lin Hsiu‐Fen , Lai Yung‐Chang , Tai Chih‐Feng , Tsai Jin‐Lian , Hsu Huan‐Chen , Hsu Ruey‐Fen , Lu Sheng‐Nan , Feng Nan‐Hsiung , Chai Chee‐Yin , Lee Chung‐Hsun 
Published: November 2012

AbstractOcular chemical burn is a severe injury with poor outcomes. Immediate and appropriate management is highly related to prognosis. We studied the effect of cultured human adipose tissue‐derived stem cells on the regeneration of the rabbit cornea after alkaline chemical burn, using used human adipose tissue‐derived stem cells as the source material. Immediately after the chemical burn, the experimental eye received a single subconjunctival injection of a stem cell suspension (1.3 × 105 cells/0.2 mL), with the other eye serving as control. Rabbits were sacrificed and specimens taken 30 days after injection. The experimental group showed faster wound healing than the control group, and the result for the experimental group was clearer cornea medium. Histologically, there were five to six epithelial cell layers on the corneas of the experimental group as compared to two to three cell layers on the corneas of the control group. Wilcoxon signed rank test showed a significant difference in the epithelial cell layers between the two groups. Surface markers for connexin 43 (Cx43), β‐catenin, E‐cadherin, and P63 were analyzed. Cx43 and β‐catenin showed significant change, as determined by the Wilcoxon signed rank test, which indicated good cell renewal during repair of the corneal epithelium damaged by the chemical burn. E‐cadherin and P63 showed no significant change during the epithelium healing process. Transplantation of cultured human adipose tissue‐derived stem cells as a treatment for a corneal chemical burn promotes cell renewal and assists in damage repair.
Zukunftsfähige Qualifikations- und Kompetenzprofile für Ärzte in Deutschland – Ergebnisse einer empirischen Studie
Authors: Evans Michaela , Hilbert Josef 
Published: November 2012

Einleitung
Die Modernisierung des Gesundheitssystems sowie der Ruf nach mehr Innovation, Qualität und Wirtschaftlichkeit erfordern in der Praxis neue und erweitere Qualifiaktionen und Kompetenzen von Ärzten. Zahlreiche Universitäten haben mit der Reform ihrer Studiengänge der Humanmedizin begonnen. Weitere Reformen sind vor allem in den Feldern Versorgungs- und Innovationsmanagament, transprofessionelles Lernen sowie Führung notwendig.
Daily Treatment Time and Functional Gains of Stroke Patients During Inpatient Rehabilitation
Authors: Wang Hua , Camicia Michelle , Terdiman Joseph , Mannava Murali K. , Sidney Stephen , Sandel M. Elizabeth 
Published: November 2012

ObjectiveTo study the effects of daily treatment time on functional gain of patients who have had a stroke.DesignA retrospective cohort study.SettingAn inpatient rehabilitation hospital (IRH) in northern California.ParticipantsThree hundred sixty patients who had a stroke and were discharged from the IRH in 2007.InterventionsAverage minutes of rehabilitation therapy per day, including physical therapy, occupation therapy, speech and language therapy, and total treatment.Main Outcome MeasuresFunctional gain measured by the Functional Independence Measure, including activities of daily living, mobility, cognition, and the total of the Functional Independence Measure (FIM) scores.ResultsThe study sample had a mean age of 64.8 years; 57.4% were men and 61.4% were white. The mean total daily therapy time was 190.3 minutes, and the mean total functional gain was 26.0. A longer daily therapeutic duration was significantly associated with total functional gain (r = .23, P = .0094). Patients who received a total therapy time of <3.0 hours per day had significantly lower total functional gain than did those treated ≥3.0 hours. No significant difference in total functional gain was found between patients treated ≥3.0 but <3.5 hours and ≥3.5 hours per day. The daily treatment time of physical therapy, occupational therapy, and speech and language therapy also was significantly associated with corresponding subscale functional gains. In addition, hemorrhagic stroke, left brain injury, earlier IRH admission, and a longer IRH stay were associated with total functional improvement.ConclusionsThe study demonstrated a significant relationship between daily therapeutic duration and functional gain during IRH stay and showed treatment time thresholds for optimal functional outcomes for patients in inpatient rehabilitation who had a stroke.
Reading Performance After Vision Rehabilitation of Subjects With Homonymous Visual Field Defects
Authors: Gall Carolin , Sabel Bernhard A. 
Published: November 2012

ObjectiveTo examine whether increased visual functioning after vision‐restoration training (VRT) coincides with improved reading abilities.DesignProspective noncontrolled open‐label trial.SettingControlled laboratory setting for all diagnostic procedures that were conducted before and after 6 months of home‐based VRT with telemedicine support.PatientsEleven subjects who had experienced a posterior‐parietal stroke and have homonymous visual field defects.InterventionsSix months of VRT (1 hour daily repeated light stimulation in the partially damaged visual field).Main outcome measurementsVRT outcome measures were the number of detected light stimuli in eye‐tracker controlled high‐resolution perimetry and the spared visual field within the affected hemifield up to the relative and absolute defect visual field border (square degrees). Enlargements of spared visual field within the affected hemifield were correlated with changes of reading speed after VRT.ResultsAfter VRT, the number of detected light stimuli increased by 5.02 ± 4.31% (mean ± SD; P = .03). The spared visual field up to the relative defect visual field border increased from 18.09 ± 32.35 square degrees before to 137.40 ± 53.32 after VRT (P = .006), as well as for the absolute defect visual field border from 36.95 ± 33.77 square degrees before VRT to 152.02 ± 49.70 after VRT (P = .005). Reading speed increased from 108.95 ± 33.95 words per minute before VRT to 122.26 ± 30.35 after VRT (P = .017), which significantly correlated with increased spared visual field up to the relative defect visual field border (r = 0.73, P = .016). Measures of eye movement variability did not correlate with VRT outcome.ConclusionsVRT improved visual fields in parafoveal areas, which are most relevant for reading. This finding cannot be explained by changes in eye movement behavior. Because of a significant association between improvements of parafoveal vision and reading speed, we propose that patients with homonymous visual field defects who have reading deficits may benefit from visual stimulation by training.
Assessment of Pelvic Floor Muscle Pressure in Female Athletes
Authors: da Silva Borin Lílian Cristina Marques , Nunes Fabiana Roberta , de Oliveira Guirro Elaine Caldeira 
Published: November 2012

ObjectiveTo evaluate the pressure of the pelvic floor muscles in female athletes and the associated signs and symptoms of stress urinary incontinence.DesignA prospective observational study.SettingAn academic institution, primary level of clinical care.ParticipantsForty women between 18 and 30 years of age divided into 4 groups: 10 volleyball players, 10 handball players, 10 basketball players, and 10 nonathletes.MethodsThe measurement of intracavity pressure was performed with use of a perineometer. The volunteers were instructed to perform 3 maximum isometric contractions of the perineum, held for 4 seconds. Data regarding specific training and urinary symptoms were collected through a questionnaire.Main Outcome MeasurementsStatistical analysis was performed by analysis of variance, with a significance level of 5%. The Spearman correlation was used to verify the degree of association between variables related to training, urinary symptoms, and perineal pressure.ResultsThe average (standard deviation) perineal pressure for nonathletes was 6.73 ± 1.91 mm Hg. The average perineal pressure for handball players was 5.55 ± 1.43 mm Hg; for volleyball players, 4.36 ± 1.43 mm Hg; and for basketball players, 3.65 ± 1.35 mm Hg. Statistically significant differences were found in the perineal pressure of volleyball (P = .009) and basketball players (P = .039) compared with nonathletes. The number of games per year, strength training, and on‐court workout correlated significantly with perineal pressure (Spearman correlation coefficient [Rs] of −0.512 for the 3 variables). Urine leakage through effort and nocturia correlated moderately with perineal pressure (Rs of −0.51 and −0.54, respectively). A strong correlation was found between urinary frequency and perineal pressure (Rs of −0.85).ConclusionsAnalysis of these data suggests that perineal pressure is decreased in female athletes compared with nonathlete women. A lower perineal pressure correlates with increased symptoms of urinary incontinence and pelvic floor dysfunction.
Fundamental domain of invariant sets and applications
Authors: ZHANG PENGFEI 
Published: November 2012

AbstractLet $X$ be a compact metric space, $f:X\to X$ a homeomorphism and $\phi \in C(X,\mathbb {R})$. We construct a fundamental domain for the set of points with finite peaks with respect to the induced cocycle $\{\phi _n\}$. As applications, we give sufficient conditions for the transitive set of a non-conservative partially hyperbolic diffeomorphism to have positive Lebesgue measure, i.e., for an accessible partially hyperbolic diffeomorphism, if the set of points with finite peaks for the Jacobian cocycle is not of full volume, then the set of transitive points is of positive volume.
Shape effects on turbulent modulation by large nearly neutrally buoyant particles
Authors: Bellani Gabriele , Byron Margaret L. , Collignon Audric G. , Meyer Colin R. , Variano Evan A. 
Published: November 2012

AbstractWe investigate dilute suspensions of Taylor-microscale-sized particles in homogeneous isotropic turbulence. In particular, we focus on the effect of particle shape on particle–fluid interaction. We conduct laboratory experiments using a novel experimental technique to simultaneously measure the kinematics of fluid and particle phases. This uses transparent particles having the same refractive index as water, whose motion we track via embedded optical tracers. We compare the turbulent statistics of a single-phase flow to the turbulent statistics of the fluid phase in a particle–laden suspension. Two suspensions are compared, one in which the particles are spheres and the other in which they are prolate ellipsoids with aspect ratio 2. We find that spherical particles at volume fraction ${\phi }_{v} = 0. 14\hspace{0.167em} \% $ reduce the turbulent kinetic energy (TKE) by 15 % relative to the single-phase flow. At the same volume fraction (and slightly smaller total surface area), ellipsoidal particles have a much smaller effect: they reduce the TKE by 3 % relative to the single-phase flow. Spectral analysis shows the details of TKE reduction and redistribution across spatial scales: spherical particles remove energy from large scales and reinsert it at small scales, while ellipsoids remove relatively less TKE from large scales and reinsert relatively more at small scales. Shape effects are far less evident in the statistics of particle rotation, which are very similar for ellipsoids and spheres. Comparing these with fluid enstrophy statistics, we find that particle rotation is dominated by velocity gradients on scales much larger than the particle characteristic length scales.
Amplitude and frequency modulation in wall turbulence
Authors: Ganapathisubramani B. , Hutchins N. , Monty J. P. , Chung D. , Marusic I. 
Published: November 2012

AbstractIn this study we examine the impact of the strength of the large-scale motions on the amplitude and frequency of the small scales in high-Reynolds-number turbulent boundary layers. Time series of hot-wire data are decomposed into large- and small-scale components, and the impact of the large scale on the amplitude and frequency of the small scales is considered. The amplitude modulation effect is examined by conditionally averaging the small-scale intensity (${ u}_{S}^{2} $) for various values of the large-scale fluctuation (${u}_{L} $). It is shown that ${ u}_{S}^{2} $ increases with increasing value of ${u}_{L} $ in the near-wall region, whereas, farther away from the wall, ${ u}_{S}^{2} $ decreases with increasing ${u}_{L} $. The rate of increase in small-scale intensity with the strength of the large-scale signal is neither symmetric (about ${u}_{L} = 0$) nor linear. The extent of the frequency modulation is examined by counting the number of occurrences of local maxima or minima in the small-scale signal. It is shown that the frequency modulation effect is confined to the near-wall region and its extent diminishes rapidly beyond ${y}^{+ } = 100$. A phase lag between the large- and small-scale fluctuations, in terms of amplitude modulation, has also been identified, which is in agreement with previous studies. The phase lag between large- and small-scale fluctuations for frequency modulation is comparable to that of amplitude modulation in the near-wall region. The combined effect of both amplitude and frequency modulation is also examined by computing conditional spectra of the small-scale signal conditioned on the large scales. In the near-wall region, the results indicate that the peak value of pre-multiplied spectra increases with increasing value of ${u}_{L} $, indicating amplitude modulation, while the frequency at which this peak occurs also increases with increasing value of ${u}_{L} $, revealing frequency modulation. The overall trends observed from the conditional spectra are consistent with the results obtained through statistical analyses. Finally, a physical mechanism that can capture most of the above observations is also presented.
Enskog kinetic theory for monodisperse gas–solid flows
Authors: Garzó V. , Tenneti S. , Subramaniam S. , Hrenya C. M. 
Published: November 2012

AbstractThe Enskog kinetic theory is used as a starting point to model a suspension of solid particles in a viscous gas. Unlike previous efforts for similar suspensions, the gas-phase contribution to the instantaneous particle acceleration appearing in the Enskog equation is modelled using a Langevin equation, which can be applied to a wide parameter space (e.g. high Reynolds number). Attention here is limited to low Reynolds number flow, however, in order to assess the influence of the gas phase on the constitutive relations, which was assumed to be negligible in a previous analytical treatment. The Chapman–Enskog method is used to derive the constitutive relations needed for the conservation of mass, momentum and granular energy. The results indicate that the Langevin model for instantaneous gas–solid force matches the form of the previous analytical treatment, indicating the promise of this method for regions of the parameter space outside of those attainable by analytical methods (e.g. higher Reynolds number). The results also indicate that the effect of the gas phase on the constitutive relations for the solid-phase shear viscosity and Dufour coefficient is non-negligible, particularly in relatively dilute systems. Moreover, unlike their granular (no gas phase) counterparts, the shear viscosity in gas–solid systems is found to be zero in the dilute limit and the Dufour coefficient is found to be non-zero in the elastic limit.
Triggering turbulence efficiently in plane Couette flow
Authors: Rabin S. M. E. , Caulfield C. P. , Kerswell R. R. 
Published: November 2012

AbstractWe use a variational formulation incorporating the full Navier–Stokes equations to identify initial perturbations with finite kinetic energy ${E}_{0} $ which generate the largest gain in perturbation kinetic energy at some time $T$ later for plane Couette flow. Using the flow geometry originally used by Butler & Farrell (Phys. Fluids A, vol. 4, 1992, pp. 1637–1650) to identify the linear transient optimal perturbations for ${E}_{0} \ensuremath{\rightarrow} 0$ and incorporating $T$ as part of the optimization procedure, we show how the addition of nonlinearity smoothly changes the result as ${E}_{0} $ increases from zero until a small but finite ${E}_{c} $ is reached. At this point, the variational algorithm is able to identify an initial condition of completely different form which triggers turbulence – called the minimal seed for turbulence. If instead $T$ is fixed at some asymptotically large value, as suggested by Pringle, Willis & Kerswell (J. Fluid Mech., vol. 703, 2012, pp. 415–443), a fundamentally different ‘final’ optimal perturbation emerges from our algorithm above some threshold initial energy ${E}_{f} \in (0, {E}_{c} )$ which shows signs of localization. This nonlinear optimal perturbation clearly approaches the structure of the minimal seed as ${E}_{0} \ensuremath{\rightarrow} { E}_{c}^{\ensuremath{-} } $, although for ${E}_{0} \lt {E}_{c} $, its maximum gain over all time intervals is always less than the equivalent maximum gain for the ‘quasi-linear optimal perturbation’, i.e. the finite-amplitude manifestation of the underlying linear optimal perturbation. We also consider a wider flow geometry recently studied by Monokrousos et al. (Phys. Rev. Lett., vol. 106, 2011, 134502) and present evidence that the critical energy for transition ${E}_{c} $ they found by using total dissipation over a time interval as the optimizing functional is recovered using energy gain at a fixed target time as the optimizing functional, with the same associated minimal seed emerging. This emphasizes that the precise form of the functional does not appear to be important for identifying ${E}_{c} $ provided it takes heightened values for turbulent flows, as postulated by Pringle, Willis & Kerswell (J. Fluid Mech., vol. 703, 2012, pp. 415–443). All our results highlight the irrelevance of the linear energy gain optimal perturbation for predicting or describing the lowest-energy flow structure which triggers turbulence.