Time-averaged MSD of Brownian motion

We study the statistical properties of the time-averaged mean-square displacements (TAMSD). This is a standard non-local quadratic functional for inferring the diffusion coefficient from an individual random trajectory of a diffusing tracer in single-particle tracking experiments. For Brownian motion, we derive an exact formula for the Laplace transform of the probability density of the TAMSD by mapping the original problem onto chains of coupled harmonic oscillators. From this formula, we deduce the first four cumulant moments of the TAMSD, the asymptotic behavior of the probability density and its accurate approximation by a generalized Gamma distribution

APOE Genotype Influences Functional Status among Elderly without Dementia

The presence of apolipoprotein-ϵ4 (APOE-ϵ4) significantly increases the risk of Alzheimer's disease (AD). The association between APOE-ϵ4 status and functional abilities was explored further in a multicultural sample of community-dwelling, non-demented elders. The sample was limited to cognitively-intact, community-dwelling elders, who were free of stroke or other neurologic disability. In 218 elders who met research criteria, the presence of APO-ϵ4 was associated with poorer functional status, apart from the effects of neuropsychological performance, gender, age, and education (OR = 2.5, 95% CI: 1.3, 4.9). In 158 subjects without an APOE-ϵ4 allele, 50% reported no functional limitation; in the 60 subjects with an ϵ4 allele, only 28% reported no functional limitation (P < .01). The relationship was not explained by the distribution of co-morbidities. The association between poorer function and the presence of an APOE-ϵ4 allele was evident in each ethnic group. In path analyses, the presence of an APOE-ϵ4 allele was associated with decreased functional ability in non-demented elders not simply through an association with poorer cognitive status, but also independently. These results suggest that the APOE-ϵ4 genotype is associated with functional deficit in people with normal neuropsychological profiles

Boundary driven zero-range processes in random media

The stationary states of boundary driven zero-range processes in random media with quenched disorder are examined, and the motion of a tagged particle is analyzed. For symmetric transition rates, also known as the random barrier model, the stationary state is found to be trivial in absence of boundary drive. Out of equilibrium, two further cases are distinguished according to the tail of the disorder distribution. For strong disorder, the fugacity profiles are found to be governed by the paths of normalized $\alpha$-stable subordinators. The expectations of integrated functions of the tagged particle position are calculated for three types of routes.Comment: 23 page

Operationalisation of Mild Cognitive Impairment: A Graphical Approach

A new online tool allows mapping of the different classifications of mild cognitive impairment

The role of parental achievement goals in predicting autonomy-supportive and controlling parenting

Although autonomy-supportive and controlling parenting are linked to numerous positive and negative child outcomes respectively, fewer studies have focused on their determinants. Drawing on achievement goal theory and self-determination theory, we propose that parental achievement goals (i.e., achievement goals that parents have for their children) can be mastery, performance-approach or performance-avoidance oriented and that types of goals predict mothers' tendency to adopt autonomy-supportive and controlling behaviors. A total of 67 mothers (aged 30-53 years) reported their goals for their adolescent (aged 13-16 years; 19.4 % girls), while their adolescent evaluated their mothers' behaviors. Hierarchical regression analyses showed that parental performance-approach goals predict more controlling parenting and prevent acknowledgement of feelings, one autonomy-supportive behavior. In addition, mothers who have mastery goals and who endorse performance-avoidance goals are less likely to use guilt-inducing criticisms. These findings were observed while controlling for the effect of maternal anxiety

Bipolar disorder and age-related functional impairment

OBJECTIVE: Although bipolar disorder is a major contributor to functional impairment worldwide, an independent impact of bipolar disorder and ageing on functioning has yet to be demonstrated. The objective of the present study was to evaluate the effect of bipolar disorder on age-related functional status using matched controls as a standard. METHOD: One-hundred patients with bipolar disorder and matched controls were evaluated for disability. Age-related effects controlled for confounders were cross-sectionally evaluated. RESULTS: Patients were significantly more impaired than controls. Regression showed effects for aging in both groups. The effect, size, however, was significantly stronger in patients. CONCLUSION: Bipolar disorder was an important effect modifier of the age impact on functioning. While a longitudinal design is needed to effectively demonstrate this different impact, this study further depicts bipolar disorder as a chronic and progressively impairing illness

Robot-assisted pelvic floor reconstructive surgery: an international Delphi study of expert users.

Robotic surgery has gained popularity for the reconstruction of pelvic floor defects. Nonetheless, there is no evidence that robot-assisted reconstructive surgery is either appropriate or superior to standard laparoscopy for the performance of pelvic floor reconstructive procedures or that it is sustainable. The aim of this project was to address the proper role of robotic pelvic floor reconstructive procedures using expert opinion. We set up an international, multidisciplinary group of 26 experts to participate in a Delphi process on robotics as applied to pelvic floor reconstructive surgery. The group comprised urogynecologists, urologists, and colorectal surgeons with long-term experience in the performance of pelvic floor reconstructive procedures and with the use of the robot, who were identified primarily based on peer-reviewed publications. Two rounds of the Delphi process were conducted. The first included 63 statements pertaining to surgeons' characteristics, general questions, indications, surgical technique, and future-oriented questions. A second round including 20 statements was used to reassess those statements where borderline agreement was obtained during the first round. The final step consisted of a face-to-face meeting with all participants to present and discuss the results of the analysis. The 26 experts agreed that robotics is a suitable indication for pelvic floor reconstructive surgery because of the significant technical advantages that it confers relative to standard laparoscopy. Experts considered these advantages particularly important for the execution of complex reconstructive procedures, although the benefits can be found also during less challenging cases. The experts considered the robot safe and effective for pelvic floor reconstruction and generally thought that the additional costs are offset by the increased surgical efficacy. Robotics is a suitable choice for pelvic reconstruction, but this Delphi initiative calls for more research to objectively assess the specific settings where robotic surgery would provide the most benefit

On the Relationship between the Conditional and Unconditional Distribution of a Random Variable

This paper studies the relationship between the unconditional and conditional distribution of the same random variable, say Y, when the distribution of the conditioning random variable X is of a known form. The problem is tackled in the general case where the distribution of Y and Y given X are mixed. Attention is focused to two particular cases. In the first X is assumed to follow a Poisson distribution; in the second X is allowed to have a mixed Poisson form. Potential applications are also discusse