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Background: Abnormal eye movements occur at the early stages of Alzheimer's disease (AD). However, the characteristics of abnormal eye movements of patients with AD and their relationship with clinical symptoms remain inconsistent, and their predictive value for diagnosing and monitoring the progression of AD remains unclear. Methods: A total of 42 normal controls, 63 patients with mild cognitive impairment due to AD (AD-MCI), and 49 patients with dementia due to AD (AD-D) were recruited. Eye movements were assessed using the EyeKnow eye-tracking and analysis system. Cognitive function, neuropsychiatric symptoms, and activities of daily living were evaluated using various rating scales, and correlation analyses and receiver operating characteristic curves were performed. Results: Patients with AD exhibited increased number of offsets and offset degrees, prolonged offset duration, and decreased accuracy in lateral fixation; reduced accuracy, prolonged saccadic duration, and decreased velocity in prosaccade; decreased accuracy and corrected rate, prolonged corrected antisaccadic duration, and reduced velocity in antisaccade; and reduced accuracy and increased inhibition failures in memory saccade. Eye movement parameters were correlated with global cognition and the cognitive domains of memory, language, attention, visuospatial ability, execution function, and activities of daily living. Subgroup analysis indicated that the associations between eye movements and clinical symptoms in patients with AD were influenced by disease severity and history of diabetes. In the AD-D and AD with diabetes groups, these associations diminished. Nevertheless, the associations persisted in the AD-MCI and AD without diabetes groups. The areas under the curves for predicting AD, AD-MCI, and AD-D were 0.835, 0.737, and 0.899, respectively (all p < 0.05). Conclusion: Patients with AD exhibit distinct patterns of abnormal eye movements. Abnormal eye movements are significantly correlated with global cognition, multiple cognitive domains, and activities of daily living. Abnormal eye movements have a considerable predictive value for the diagnosis and progression of AD. [ABSTRACT FROM AUTHOR]

Aims: This study aimed to comprehensively explore the nutrition and gait of AD patients at different stages and the relationship between them. Methods: A total of 85 AD patients were consecutively enrolled in this cross‐sectional study and divided into the mild cognitive impairment (MCI) due to AD (AD‐MCI) and the dementia due to AD (AD‐D) groups. Demographic information, nutritional status, and gait performance were compared between the two groups, and the correlation between nutritional status and gait performance was subsequently analyzed by Pearson and Spearman correlation analyses. Results: The AD‐D group had lower scores on Mini‐Nutritional Assessment (MNA) and MNAm scales, lower levels of urea nitrogen, folic acid, and vitamin B12 in blood, and higher homocysteine level than those in the AD‐MCI group (all p < 0.05). The AD‐D group had slower step speed, shorter step length, and shorter stride length than those in the AD‐MCI group (all p < 0.05). AD patients with decreased scores of MNA and MNAm scales, and declined levels of urea nitrogen and vitamin B12 in blood had reduced gait speed and gait cadence, and prolonged step length time and stride length time, whereas homocysteine showed the almost opposite results (all p < 0.05). In the AD‐MCI group, the score of scale was negatively correlated with the coefficient of variation (CV) of stride length, and the folic acid level was negatively correlated with the CV of stride length and cadence (all p < 0.05). Conclusions: AD patients at the dementia stage had worse nutritional status and gait performance than those at the MCI stage, which was associated with worse global cognition and activities of daily living. Poorer nutritional status was associated with higher gait variability in patients at the MCI stage and with poorer gait performance in patients at the dementia stage. Early identification and intervention of patients with nutritional risk or malnutrition may improve gait performance, thus reducing the risk of falling and cognitive decline, as well as the mortality. [ABSTRACT FROM AUTHOR]

Cutoff walls are widely used as in‐situ geoenvironmental barriers to isolate the contaminants caused by landfill leakage, chemical storage tank accidents, and mining activities. A two‐dimensional analytical solution is developed to investigate the behavior of organic chemical transport in cutoff wall and aquifer. The method of Laplace transforms and finite Fourier cosine transform is adopted to derive the solution for a finite domain. The proposed analytical solutions are verified by the numerical approach. The effects of contaminant source distribution, aquifer scale, direction of flow rate, degradation, adsorption, and thickness of cutoff wall were investigated. The investigation of non‐uniformly distribution of contamination sources indicates that the 1‐D models lead to a more conservative result compared to the 2‐D models. Biodegradation will be a dominant process and significantly enhance the performances of the barrier system when the half‐life of contaminant is less than 4 years. Furthermore, the effect of dimension on breakthrough time can be augmented with the increase of distribution coefficient. [ABSTRACT FROM AUTHOR]