Technologies for imaging neural activity in large volumes

Neural circuitry has evolved to form distributed networks that act dynamically across large volumes. Collecting data from individual planes, conventional microscopy cannot sample circuitry across large volumes at the temporal resolution relevant to neural circuit function and behaviors. Here, we review emerging technologies for rapid volume imaging of neural circuitry. We focus on two critical challenges: the inertia of optical systems, which limits image speed, and aberrations, which restrict the image volume. Optical sampling time must be long enough to ensure high-fidelity measurements, but optimized sampling strategies and point spread function engineering can facilitate rapid volume imaging of neural activity within this constraint. We also discuss new computational strategies for the processing and analysis of volume imaging data of increasing size and complexity. Together, optical and computational advances are providing a broader view of neural circuit dynamics, and help elucidate how brain regions work in concert to support behavior

Therapeutic benefit of aripiprazole-olanzapine combination in the treatment of senile Alzheimer’s disease complicated by mental disorders

Purpose: To determine the clinical efficacy of aripiprazole-olanzapine combination treatment in elderly Alzheimer’s disease complicated with mental disorders. Methods: Ninety-two elderly patients with Alzheimer’s disease and mental disorders who were admitted to Binzhou People's Hospital, were enrolled in the study. They were randomized into control and study groups. Control group was treated with olanzapine, while the study group was treated with aripiprazole as an adjuvant therapy in addition to olanzapine. The clinical efficacy, scores on different scales (MMSE, ADAS-cog, CDR, ADL, NPI and CMAI), and incidence of adverse reactions were determined. Results: The overall degree of response was significantly higher in the study group than in the control group (p < 0.05). There were no significant differences in MMSE, ADAS-cog, CDR, ADL, NPI and CMAI scores between the two groups before treatment (p > 0.05). The MMSE score of the study group was significantly higher than that of the control group, and the scores in the other scales in the study group were significantly lower after treatment (p < 0.05). The study group had significantly lower incidence of adverse reactions than control group (p < 0.05). Conclusion: Aripiprazole-olanzapine combination has significant therapeutic benefit in the treatment of elderly Alzheimer’s disease patients complicated with mental disorders. It promotes recovery of neurological function, as well as produces a lower incidence of adverse reactions. Keywords: Aripiprazole, Olanzapine, Alzheimer’s disease, Mental disorder

Early Abnormal Temperature Structure of X-ray Looptop Source of Solar Flares

This Letter is to investigate the physics of a newly discovered phenomenon -- contracting flare loops in the early phase of solar flares. In classical flare models, which were constructed based on the phenomenon of expansion of flare loops, an energy releasing site is put above flare loops. These models can predict that there is a vertical temperature gradient in the top of flare loops due to heat conduction and cooling effects. Therefore, the centroid of an X-ray looptop source at higher energy bands will be higher in altitude, for which we can define as normal temperature distribution. With observations made by {\it RHESSI}, we analyzed 10 M- or X-class flares (9 limb flares). For all these flares, the movement of looptop sources shows an obvious U-shaped trajectory, which we take as the signature of contraction-to-expansion of flare loops. We find that, for all these flares, normal temperature distribution does exist, but only along the path of expansion. The temperature distribution along the path of contraction is abnormal, showing no spatial order at all. The result suggests that magnetic reconnection processes in the contraction and expansion phases of these solar flares are different.Comment: 11 pages, 4 figure

Sum-Frequency Generation from Chiral Media and Interfaces

Sum frequency generation (SFG), a second-order nonlinear optical process, is electric-dipole forbidden in systems with inversion symmetry. As a result, it has been used to study chiral media and interfaces, systems intrinsically lacking inversion symmetry. This thesis describes recent progresses in the applications of and new insights into SFG from chiral media and interfaces. SFG from solutions of chiral amino acids is investigated, and a theoretical model explaining the origin and the strength of the chiral signal in electronic-resonance SFG spectroscopy is discussed. An interference scheme that allows us to distinguish enantiomers by measuring both the magnitude and the phase of the chiral SFG response is described, as well as a chiral SFG microscope producing chirality-sensitive images with sub-micron resolution. Exploiting atomic and molecular parity nonconservation, the SFG process is also used to solve the Ozma problems. Sum frequency vibrational spectroscopy is used to obtain the adsorption behavior of leucine molecules at air-water interfaces. With poly(tetrafluoroethylene) as a model system, we extend the application of this surface-sensitive vibrational spectroscopy to fluorine-containing polymers