Sluggish anion transport provides good kinetic stability to the anhydrous anti-perovskite solid electrolyte Li3OCl.

Some lithium oxyhalides have been proposed as low-cost solid electrolytes for having room-temperature Li+ conductivity close to commercial liquid electrolytes, but with the advantages of enabling higher energy densities through the use of the Li metal anode and not being flammable. However, the stability of anhydrous anti-perovskite lithium oxyhalides, such as Li3OCl, is not well understood yet: whereas theoretical calculations show they should decompose into lithium halides and Li2O (except at high temperatures), there is no experimental evidence of such decomposition. Thus, here we use a combination of analytical calculations and force-field-based atomistic modelling to investigate the role of kinetics in the stability of anhydrous Li3OCl. The results show that due to sluggish Cl- and O2- transport this material has good kinetic stability below ∼400 K under high concentration gradients, below ∼450 K under typical cell voltages, and at all temperatures against local composition fluctuations. Furthermore, the good kinetic stability explains the apparent discrepancy between theoretical thermodynamics calculations and experimental observations and contributes to enlighten the nature and extent of this material's stability. The methods presented here can also be extended to other battery materials that are predicted to decompose, to access the safe temperature range they can undergo without degrading.

Tolerance factor for pyrochlores and related structures.

In this work a new empirical tolerance factor for compounds with pyrochlore structure is proposed. This suggested tolerance factor is based on experimental structural data and on the tolerance factors proposed. However, since it does not depend on the structural data, this new tolerance factor permits the prediction of some properties of these compounds directly. Also, a good structure stability field for the pyrochlore formation is observed when this tolerance factor is used.

Effect of aerobic training on EEG alpha asymmetry and depressive symptoms in the elderly: a 1-year follow-up study.

The effect of physical exercise on the treatment of depressive elderly adults has not been investigated thus far in terms of changes in cortical hemispheric activity. The objective of the present study was to identify changes in depressive symptoms, quality of life, and cortical asymmetry produced by aerobic activity. Elderly subjects with a diagnosis of major depressive disorder (DSM-IV) were included. Twenty patients (70% females, 71 +/- 3 years) were divided into an exercise group (pharmacological treatment plus aerobic training) and a control group (undergoing pharmacological treatment) in a quasi-experimental design. Pharmacological treatment was maintained stable throughout the study (antidepressants and anxiolytics). Subjects were evaluated by depression scales (Beck Depression Inventory, Hamilton Depression Rating Scale, Montgomery-Asberg Depression Rating Scale) and the Short Form Health Survey-36, and electroencephalographic measurements (frontal and parietal alpha asymmetry) before and after 1 year of treatment. After 1 year, the control group showed a decrease in cortical activity on the right hemisphere (increase of alpha power), which was not observed in the exercise group. The exercise group showed a significant decrease of depressive symptoms, which was not observed in the control group. This result was also accompanied by improved treatment response and remission rate after 1 year of aerobic exercise associated with treatment. This study provides support for the effect of aerobic training on alpha activity and on depressive symptoms in elderly patients. Exercise facilitates the treatment of depressive elderly adults, leading to clinical and physical improvement and protecting against a decrease in cortical activity.

Effect of aerobic training on EEG alpha asymmetry and depressive symptoms in the elderly: a 1-year follow-up study

The effect of physical exercise on the treatment of depressive elderly adults has not been investigated thus far in terms of changes in cortical hemispheric activity. The objective of the present study was to identify changes in depressive symptoms, quality of life, and cortical asymmetry produced by aerobic activity. Elderly subjects with a diagnosis of major depressive disorder (DSM-IV) were included. Twenty patients (70 percent females, 71 ± 3 years) were divided into an exercise group (pharmacological treatment plus aerobic training) and a control group (undergoing pharmacological treatment) in a quasi-experimental design. Pharmacological treatment was maintained stable throughout the study (antidepressants and anxiolytics). Subjects were evaluated by depression scales (Beck Depression Inventory, Hamilton Depression Rating Scale, Montgomery-Asberg Depression Rating Scale) and the Short Form Health Survey-36, and electroencephalographic measurements (frontal and parietal alpha asymmetry) before and after 1 year of treatment. After 1 year, the control group showed a decrease in cortical activity on the right hemisphere (increase of alpha power), which was not observed in the exercise group. The exercise group showed a significant decrease of depressive symptoms, which was not observed in the control group. This result was also accompanied by improved treatment response and remission rate after 1 year of aerobic exercise associated with treatment. This study provides support for the effect of aerobic training on alpha activity and on depressive symptoms in elderly patients. Exercise facilitates the treatment of depressive elderly adults, leading to clinical and physical improvement and protecting against a decrease in cortical activity.