Ultra-compact acousto-optic modulation using on-chip integrated Bragg gratings on lithium niobate-chalcogenide hybrid platform.

An ultra-compact and efficient acousto-optic modulator based on a thin-film lithium niobate-chalcogenide (ChG) hybrid platform was designed and realized. In this approach, π phase-shift Bragg grating has an ultra-short effective interaction length of only ∼ 300 µm and a compact footprint of 200 × 300 µm2. The strong microwave-acoustic coupling and superior photo-elastic property of the ChG allow us to achieve a half-wave voltage of Vπ = 1.08 V (4.07 V) for the π phase-shift Bragg grating (waveguide Bragg grating), corresponding to VπL = 0.03 V·cm (0.09 V·cm). This acousto-optic modulator exhibits a compact size, and low power consumption, and can be used for on-chip optical interconnects and microwave photonics.

Parallel interrogation of the chalcogenide-based micro-ring sensor array for photoacoustic tomography.

Photoacoustic tomography (PAT), also known as optoacoustic tomography, is an attractive imaging modality that provides optical contrast with acoustic resolutions. Recent progress in the applications of PAT largely relies on the development and employment of ultrasound sensor arrays with many elements. Although on-chip optical ultrasound sensors have been demonstrated with high sensitivity, large bandwidth, and small size, PAT with on-chip optical ultrasound sensor arrays is rarely reported. In this work, we demonstrate PAT with a chalcogenide-based micro-ring sensor array containing 15 elements, while each element supports a bandwidth of 175 MHz (-6 dB) and a noise-equivalent pressure of 2.2 mPaHz-1/2. Moreover, by synthesizing a digital optical frequency comb (DOFC), we further develop an effective means of parallel interrogation to this sensor array. As a proof of concept, parallel interrogation with only one light source and one photoreceiver is demonstrated for PAT with this sensor array, providing images of fast-moving objects, leaf veins, and live zebrafish. The superior performance of the chalcogenide-based micro-ring sensor array and the effectiveness of the DOFC-enabled parallel interrogation offer great prospects for advancing applications in PAT.

Efficient acousto-optic modulation using a microring resonator on a thin-film lithium niobate-chalcogenide hybrid platform.

This Letter presents the first, to the best of our knowledge, thin-film lithium niobate-chalcogenide based microring acousto-optic modulator where an interdigital transducer and a chalcogenide strip waveguide are integrated on X-cut thin-film lithium niobate. The microring resonator exhibits a high loaded quality factor of 5 × 105. The developed hybrid acousto-optic modulator with an interaction length of 120 µm demonstrates an effective half-wave voltage of only 1.74 V, which corresponds to a voltage-length product of 0.02 V•cm. The performance of the acousto-optic modulator demonstrated on the unsuspended thin-film lithium niobate-chalcogenide waveguide platform is on par with that obtained from an acoustic cavity assisted homogeneous lithium niobate counterpart.

Effects of Mindfulness-Based Cognitive Therapy on Stigma in Female Patients With Schizophrenia.

Mindfulness-based cognitive therapy (MBCT) has been increasingly recognized as effective in different mental illnesses, but these effects are limited in schizophrenia. For patients with schizophrenia, stigma is one of the most negative factors that affects treatment, rehabilitation and social function. This research aimed to determine the effects of MBCT on stigma in patients with schizophrenia. In total, 62 inpatients with schizophrenia were recruited and randomly assigned to the experimental group or control group. The experimental group received an 8-week MBCT intervention, and the control group were treated as usual. Link's Stigma Scales (with three subscales, including perceived devaluation-discrimination (PDD), stigma-coping orientation, and stigma-related feeling), Five Facet Mindfulness Questionnaire (FFMQ), and Insight and Treatment Attitudes Questionnaire (ITAQ) were used to collect data before and after intervention. After intervention, the post-test score of PDD, stigma-coping orientation, FFMQ, and ITAQ were significantly different between the experimental group and the control group. In the experimental group, the PDD and stigma-coping orientation scores significantly decreased, and FFMQ and ITAQ scores increased remarkably (P < 0.05). In addition, correlation analysis revealed a significant negative correlation between mindfulness and stigma. MBCT was effective in reducing stigma in patients with schizophrenia, which mainly manifested as changes in the patients' perception of stigma as well as the withdrawal and avoidance caused by schizophrenia. Enhancing mindfulness will help reduce the stigma level. MBCT is worthy of promotion and application in patients with schizophrenia.

Effect of music intervention on apathy in nursing home residents with dementia.

This study examined the effectiveness of group music intervention in the treatment of nursing home residents with apathy. Apathy can clinically defined with a score of 40 or above on the apathy evaluation scale (AES). Seventy-seven residents were randomly assigned to the intervention or control group. The intervention group was given a music intervention programme, which included listening to traditional music, including nostalgic songs, and playing musical instruments three times a week, for a total of twelve weeks. Results demonstrated a decrease in apathy scores in the intervention group (z = 4.667, P <0.01), but not in the control group (z = -1.810, P > 0.05). Cognitive function, as assessed by Mini Mental State Examination (MMSE) score, was stable in the intervention group (t = 1.720, P > 0.05), but declined in the control group (t = -1.973, P <0.05). We conclude that music intervention has the potential to be an effective therapy for the treatment of apathy in the early stages of dementia.

Extraction of genomic DNA using a new amino silica monolithic column.

A new amino silica monolithic column was developed for DNA extraction in a miniaturized format. The monolithic column was prepared in situ by polymerization of tetraethoxysilane (TEOS) and N-(beta-aminoethyl)-gamma-aminopropylmethyldimethoxysilane (AEAPMDMS). DNA was loaded in 50 mM tris(hydroxylmethyl)aminomethane-EDTA buffer at pH 7.0 and eluted with 300 mM potassium phosphate solution at pH 10.0. Under optimal condition, a 6.0-cm monolithic column provided a capacity of 56 ng DNA with an extraction efficiency of 71 +/- 5.2% (X +/- RSD). When the amino silica monolithic column was applied to extract genomic DNA from the whole blood of crucian carp, an extraction efficiency of 52 +/- 5.6% (X +/- RSD) was obtained by three extractions. Since the chaotropic-based sample loading and organic solvent wash steps were avoided in this procedure, the purified DNA was suitable for downstream processes such as PCR. This amino silica monolithic column was demonstrated to allow rapid and efficient DNA purification in microscale.

Rapid recovery of DNA from agarose gel slices by coupling electroelution with monolithic SPE.

An amino silica monolithic column prepared by in situ polymerization of tetraethoxysilane and N-(beta-aminoethyl)-gamma-aminopropyltriethoxysilane was firstly applied to recover DNA from agarose gel slices by coupling electroelution with monolithic SPE. DNA was electroeluted from the agarose gel slices onto the amino silica monolithic column. The DNA adsorbed on this monolithic column was then recovered using sodium phosphate solution at pH 10. The whole recovery procedure could be completed within 10 min because the use of amino silica monolithic column accelerated the DNA capture and facilitated the DNA release. Electroelution conditions, such as buffer pH, buffer concentration and applied voltage, were online optimized. The average yield for herring sperm DNA, pBR 322 DNA and lambda DNA recovered from 1.0% w/v agarose gel slices were 55+/-4, 50+/-6 and 42+/-7% (n=3), respectively. The polymerase chain reaction performance of pGM plasmid recovered from agarose gel slices demonstrated that the method could provide high-quality DNA for downstream processes. The combination of electroelution with monolithic SPE allows a rapid, simple and efficient DNA recovery method. This technique is especially useful for applications that need to purify small starting amounts of DNA.