[Effects of UV Radiation on the Coagulation Process of Kaolin and Involved Mechanisms].

Kaolin commonly exists in water,and it has an important impact on the water treatment processes and contaminants'migration and transformation.In this study,PAC was used as flocculating agent to systematically investigate the effects of UV radiation on the coagulation process of kaolin by jar test.The results showed that under neutral and acidic conditions,UV radiation could promote the coagulation process of kaolin suspension.When the solution pH,coagulant dosage and irradiation time were 7.0,30 mg·L-1 and 2.0 h,respectively,the kaolin remove rate of effluent after coagulation increased from 81.05% to 93.90% by using UV radiation.This might be related to the decrease of-OH stretching vibration absorption peak and the enhancement of Si-O stretching vibration absorption peak and Si-O bending vibration absorption peak after UV radiation,so that the number of the active spot (-OH) on kaolin surface declined.These changes might lead to decrease of the negative charge on kaolin surface,which promoted kaolin suspension to precipitate in coagulation process.However,under alkaline conditions,its settlement performance was slightly lower than the water samples without ultraviolet radiation treatment.

MREJ: MRE elasticity reconstruction on ImageJ.

Magnetic resonance elastography (MRE) is a promising method for health evaluation and disease diagnosis. It makes use of elastic waves as a virtual probe to quantify soft tissue elasticity. The wave actuator, imaging modality and elasticity interpreter are all essential components for an MRE system. Efforts have been made to develop more effective actuating mechanisms, imaging protocols and reconstructing algorithms. However, translating MRE wave images into soft tissue elasticity is a nontrivial issue for health professionals. This study contributes an open-source platform - MREJ - for MRE image processing and elasticity reconstruction. It is established on the widespread image-processing program ImageJ. Two algorithms for elasticity reconstruction were implemented with spatiotemporal directional filtering. The usability of the method is shown through virtual palpation on different phantoms and patients. Based on the results, we conclude that MREJ offers the MRE community a convenient and well-functioning program for image processing and elasticity interpretation.

Abnormal brain default-mode network functional connectivity in drug addicts.

BACKGROUND: The default mode network (DMN) is a set of brain regions that exhibit synchronized low frequency oscillations at resting-state, and is believed to be relevant to attention and self-monitoring. As the anterior cingulate cortex and hippocampus are impaired in drug addiction and meanwhile are parts of the DMN, the present study examined addiction-related alteration of functional connectivity of the DMN. METHODOLOGY: Resting-state functional magnetic resonance imaging data of chronic heroin users (14 males, age: 30.1±5.3 years, range from 22 to 39 years) and non-addicted controls (13 males, age: 29.8±7.2 years, range from 20 to 39 years) were investigated with independent component analysis to address their functional connectivity of the DMN. PRINCIPAL FINDINGS: Compared with controls, heroin users showed increased functional connectivity in right hippocampus and decreased functional connectivity in right dorsal anterior cingulate cortex and left caudate in the DMN. CONCLUSIONS: These findings suggest drug addicts' abnormal functional organization of the DMN, and are discussed as addiction-related abnormally increased memory processing but diminished cognitive control related to attention and self-monitoring, which may underlie the hypersensitivity toward drug related cues but weakened strength of cognitive control in the state of addiction.

Addiction related alteration in resting-state brain connectivity.

It is widely accepted that addictive drug use is related to abnormal functional organization in the user's brain. The present study aimed to identify this type of abnormality within the brain networks implicated in addiction by resting-state functional connectivity measured with functional magnetic resonance imaging (fMRI). With fMRI data acquired during resting state from 14 chronic heroin users (12 of whom were being treated with methadone) and 13 non-addicted controls, we investigated the addiction related alteration in functional connectivity between the regions in the circuits implicated in addiction with seed-based correlation analysis. Compared with controls, chronic heroin users showed increased functional connectivity between nucleus accumbens and ventral/rostral anterior cingulate cortex (ACC), between nucleus accumbens and orbital frontal cortex (OFC), and between amygdala and OFC and reduced functional connectivity between prefrontal cortex and OFC and between prefrontal cortex and ACC. These observations of altered resting-state functional connectivity suggested abnormal functional organization in the addicted brain and may provide additional evidence supporting the theory of addiction that emphasizes enhanced salience value of a drug and its related cues but weakened cognitive control in the addictive state.

[Evaluation of Gd-DTPA enhanced MR in the diagnosis of the degeneration stage of cerebral cysticercosis].

OBJECTIVE: To detect the value of qualitative and orientating diagnosis in the degeneration stage of cerebral cysticercosis with Gd-DTPA enhanced MR. METHODS: Sixty-nine cases of cerebral cysticercosis were diagnosed by enhanced MR as degeneration stage, and confirmed by immunological examination and/or by surgery. MR plain scanning was conducted for the same cases. RESULTS: The plain scanning showed single or multiple lesions with long T1 and long T2 signals, and the enhanced scanning showed nodular or annular lesions. The diameter of the lesion after enhanced scan was not more than 22 mm with an average value of 8.1 mm. Some cases showed single lesion on plain scanning but showed multiple lesions after enhanced scan. CONCLUSION: The enhanced MR shows more typical features of the degeneration stage cerebral cysticercosis. It can define the number, position and range of the lesions, and can improve the accuracy of differential diagnosis, and therefore be of importance in formulating treatment scheme and prognosis.