Associations between social and intellectual activities with cognitive trajectories in Chinese middle-aged and older adults: A nationally representative cohort study

BACKGROUND: Associations between the frequency of social and intellectual activities and cognitive trajectories are understudied in Chinese middle-aged and older adults. We aimed to examine this association in a nationally representative longitudinal study. METHODS: The China Health and Retirement Longitudinal Study (CHARLS) is a nationally representative sample of Chinese middle-aged and older participants. The frequency of social and intellectual activities was measured at baseline. Interview-based cognitive assessments of orientation and attention, episodic memory, and visuospatial skills and the calculation of combined global scores were assessed every 2 years from 2011 to 2016. Cognitive aging trajectories over time were analyzed using group-based trajectory modeling, and the associations of the trajectory memberships with social and intellectual activities were analyzed using multinomial logistic regression. Odds ratios (OR) and 95% confidence intervals (CI) were reported. RESULTS: Among 8204 participants aged 50-75 years at baseline, trajectory analysis identified three longitudinal patterns of cognitive function based on the global cognitive scores: persistently low trajectory (n = 1550, 18.9%), persistently moderate trajectory (n = 3194, 38.9%), and persistently high trajectory (n = 3460, 42.2%). After adjustment for sociodemographic variables, lifestyles, geriatric symptoms, and health conditions, more frequent intellectual activities (OR 0.54, 95% CI 0.38-0.77) and social activities (OR 0.79, 95% CI 0.65-0.95) were both associated with a lower likelihood of being in the persistently low trajectory for global cognitive function. CONCLUSIONS: These findings suggested that more frequent social and intellectual activities were associated with more favorable cognitive aging trajectories

Contourlet textual features: Improving the diagnosis of solitary pulmonary nodules in two dimensional ct images

Materials and Methods: A total of 6,299 CT images were acquired from 336 patients, with 1,454 benign pulmonary nodule images from 84 patients (50 male, 34 female) and 4,845 malignant from 252 patients (150 male, 102 female). Further to this, nineteen patient information categories, which included seven demographic parameters and twelve morphological features, were also collected. A contourlet was used to extract fourteen types of textural features. These were then used to establish three support vector machine models. One comprised a database constructed of nineteen collected patient information categories, another included contourlet textural features and the third one contained both sets of information. Ten-fold cross-validation was used to evaluate the diagnosis results for the three databases, with sensitivity, specificity, accuracy, the area under the curve (AUC), precision, Youden index, and F-measure were used as the assessment criteria. In addition, the synthetic minority over-sampling technique (SMOTE) was used to preprocess the unbalanced data.Results: Using a database containing textural features and patient information, sensitivity, specificity, accuracy, AUC, precision, Youden index, and F-measure were: 0.95, 0.71, 0.89, 0.89, 0.92, 0.66, and 0.93 respectively. These results were higher than results derived using the database without textural features (0.82, 0.47, 0.74, 0.67, 0.84, 0.29, and 0.83 respectively) as well as the database comprising only textural features (0.81, 0.64, 0.67, 0.72, 0.88, 0.44, and 0.85 respectively). Using the SMOTE as a pre-processing procedure, new balanced database generated, including observations of 5,816 benign ROIs and 5,815 malignant ROIs, and accuracy was 0.93.Objective: To determine the value of contourlet textural features obtained from solitary pulmonary nodules in two dimensional CT images used in diagnoses of lung cancer. Copyright:Conclusion: Our results indicate that the combined contourlet textural features of solitary pulmonary nodules in CT images with patient profile information could potentially improve the diagnosis of lung cancer

Cognitive impairment and risk of all-cause and cardiovascular disease mortality over 20-year follow-up: Results from the BLSA

Background-Cognitive impairment may increase the risk of all-cause and cardiovascular disease (CVD) mortality. This study examined the association between cognitive function and risk of all-cause and CVD mortality among the elderly in Beijing, China. Methods and Results-A total of 1996 participants aged ≥55 years at baseline were enrolled from the BLSA (Beijing Longitudinal Study of Aging). Cognitive function was assessed using the Mini-Mental State Examination (MMSE), and participants were categorized as

A note on worst-case performance of heuristics for maintenance scheduling problems

We study a machine scheduling model in which job scheduling and machine maintenance activities have to be considered simultaneously. We develop the worst-case bounds for some heuristic algorithms, including a sharper worst-case bound of the SPT schedule than the results in the literature, and another bound of the EDD schedule. (c) 2006 Elsevier B.V. All rights reserved

Two-Stage Supply Chain Scheduling with an Option of Outsourcing in Stage One

This paper studies a two-stage supply chain scheduling problem with n job orders where each job needs two sequential operations. In addition to the two in-house machines each for one operation, the manufacturer has another option of outsourcing some stage-one operations to an outside subcontractor. The jobs with their stage-one operation outsourced are subject to a single batch delivery from the subcontractor before their respective stage-two operations can be started in-house. The problem is to design an integrated scheduling that considers both the in-house production and the outsourcing with the aim of optimally balancing the outsourcing cost and the makespan. The problem is NP-hard. We have developed a heuristic algorithm to solve the problem, and conducted computational experiments to validate our model and algorithm

TWO-STAGE PRODUCTION SCHEDULING WITH AN OPTION OF OUTSOURCING FROM A REMOTE SUPPLIER

This paper studies a two-stage production system with n job orders where each job needs two sequential operations. In addition to the two in-house production facilities, the manufacturer has another option of outsourcing some stage-one operations to a remote outside supplier. The jobs with their stage-one operations outsourced are subject to a batch transportation delay from the outside supplier before their respective stage-two operations can be started in-house. The problem is to design an integrated schedule that considers both the in-house production and the outsourcing with the aim of optimally balancing the outsourcing cost and the makespan. The problem is NP-hard. We have developed an optimal algorithm and a heuristic algorithm to solve the problem, and conducted computational experiments to validate our model and algorithms. Our modeling and algorithm framework can be extended to handle other more general cases such as when the outside supplier has a production facility with a different processing efficiency and when there are many outside suppliers on a spot market

Outsourcing and production scheduling for a two-stage flow shop

In this paper we study the production scheduling problem for a two-stage flow shop in which there are options of outsourcing some operations to subcontractors. The basic objective is to look for a production schedule that can optimally utilize the resources of both the in-house production and outsourcing so that the makespan is minimized. The logistics issue between the subcontractor and the in-house shop further complicates the problem. We present models for different situations of outsourcing. For each model, we develop optimization algorithms and conduct computational experiments to study the managerial insights for the models and the algorithms.Production scheduling Outsourcing Flow shop

Modeling and optimization for disruption management

textDisruption management is about how to deal with uncertainties in the execution period of an operational plan. While it has been successfully applied in airlines scheduling, the research of disruption management in manufacturing and logistics is still in its infancy. In this disertation, we study several dsiruption management problems in machine scheduling, production planning, supply chain coordination, and class scheduling for pilot training. We address various disruptions, propose mathematical models, and present solution schemes. This research is one of the first attempts to systematically study disruption management in manufacturing and logistics, and has both important theoritical and practical contributions.Managemen