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To explore the resting state networks (RSNs) alterations in patients with unilateral mesial temporal lobe epilepsy (mTLE) before and after successful surgery.Resting-state functional MRI and T1-weighted structural MRI were obtained in 37 mTLE patients who achieved seizure freedom after anterior temporal lobectomy. Patients were scanned before surgery and at two years after surgery. Twenty-eight age- and sex-matched healthy controls were scanned once. Functional connectivity (FC) changes within and between ten common RSNs before and after surgery, and FC changes between hippocampus and RSNs were explored.Before surgery, decreased FC was found within visual network and basal ganglia network, while after surgery, FC within basal ganglia network further decreased but FC within sensorimotor network and dorsal attention network increased. Before surgery, between-network FC related to basal ganglia network, visual network and dorsal attention network decreased, while between-network FC related to default mode network increased. After surgery, between-network FC related to visual network and dorsal attention network significantly increased. In addition, before surgery, ipsilateral hippocampus showed decreased FC with visual network, basal ganglia network, sensorimotor network, default mode network and frontoparietal network, while contralateral rostral hippocampus showed increased FC with salience network. After surgery, no obvious FC changes were found between contralateral hippocampus and these RSNs.MTLE patients showed significant RSNs alterations before and after surgery. Basal ganglia network showed progressive decline in functional connectivity. Successful surgery may lead to RSNs reorganization. These results provide preliminary evidence for postoperative functional remodeling at whole-brain-network level.

To explore dynamic alterations of cortical thickness before and after successful anterior temporal lobectomy (ATL) in patients with unilateral mesial temporal lobe epilepsy (mTLE).High-resolution T1-weighted MRI was obtained in 28 mTLE patients who achieved seizure freedom for at least 24 months after ATL and 29 healthy controls. Patients were scanned at five timepoints, including before surgery, 3, 6, 12 and 24 months after surgery. Preoperative cortical thickness of mTLE patients were compared with healthy controls. Dynamic alterations of cortical thickness before and after surgery were compared among five scans using linear mixed models.Patients with mTLE showed cortical thinning pre-surgically in ipsilateral entorhinal cortex, parahippocampal gyrus, inferior parietal cortex, lateral occipital cortex; contralateral pericalcarine cortex (PCC); and bilateral caudal middle frontal gyrus (cMFG), paracentral lobule, precentral gyrus (PCG), superior parietal cortex. Cortical thickening was observed in contralateral rostral anterior cingulate cortex (rACC). Patients showed postsurgical cortical thinning in ipsilateral temporal lobe, fusiform gyrus, caudal anterior cingulate cortex, lingual gyrus, and insula. Ipsilateral cMFG, PCC, and contralateral PCG showed significant cortical thickening after surgery. In addition, contralateral rACC showed cortical thickening at 3 months follow-up, however, with obvious cortical thinning at 24 months follow-up.Mesial temporal lobe epilepsy patients showed widespread cortical thinning before and after anterior temporal lobectomy. Progressive cortical thinning mainly existed in neighboring regions of resection. Postoperative cortical thickening may indicate cortical remodeling after successful surgery.

Ammonium recovery from wastewater by gas-permeable membranes is promising but suffers from the tradeoff between membrane stability and permeability under harsh operating conditions. Chemical-resistant membranes display modest permeability due to the poor solubility and processibility; chemically active membranes are easier to be endowed with better permeability however hinder by instability. To resolve such a problem, we cleverly design a novel membrane configuration via one-step solution-electrospinning, with the chemical-active component (low-strength fluorine polymer) as the inner skeleton to construct interconnected porous structures and the chemical-resistant component (high-strength fluorine polymer) as the outer armor to serve as a protective layer. Due to the significantly enhanced mass transfer coefficient, the interconnected-porous armor-structured membrane exhibited much higher permeability for NH

Unilateral temporal lobe epilepsy (TLE) is the most common type of focal epilepsy characterized by foci in the unilateral temporal lobe grey matters of regions such as the hippocampus. However, it remains unclear how the functional features of white matter are altered in TLE. In the current study, resting-state functional magnetic resonance imaging (fMRI) was performed on 71 left TLE (LTLE) patients, 79 right TLE (RTLE) patients and 47 healthy controls (HC). Clustering analysis was used to identify fourteen white matter networks (WMN). The functional connectivity (FC) was calculated among WMNs and between WMNs and grey matter. Furthermore, the FC laterality of hemispheric WMNs was assessed. First, both patient groups showed decreased FCs among WMNs. Specifically, cerebellar white matter illustrated decreased FCs with the cerebral superficial WMNs, implying a dysfunctional interaction between the cerebellum and the cerebral cortex in TLE. Second, the FCs between WMNs and the ipsilateral hippocampus (grey matter foci) were also reduced in patient groups, which may suggest insufficient functional integration in unilateral TLE. Interestingly, RTLE showed more severe abnormalities of white matter FCs, including links to the bilateral hippocampi and temporal white matter, than LTLE. Taken together, these findings provide functional evidence of white matter abnormalities, extending the understanding of the pathological mechanism of white matter impairments in unilateral TLE.

Traditional village tourism is an effective path to rural revitalization and an excellent way to preserve traditional sceneries and cultural heritage. However, research on the subject matter has been limited. To address some of the current research gaps, this study used 2372 online travelogues from popular travel websites to explore the spatio-temporal distribution and network structure of the tourism flow in traditional villages in western Hunan using ArcGIS and social network analysis. The main findings are as follows: (1) In terms of time distribution, the tourism flow in traditional villages in Western Hunan is dominated by short-term tourism and shows significant seasonal differences. (2) The spatial distribution forms a double-core and multipoint spatial pattern with “Fenghuang Ancient City—Zhangjiajie National Forest Park” as core. (3) The network of traditional villages in Western Hunan exhibits a “core-periphery” hierarchical structure, with a network density of 0.275. Aside from the attraction and appeal of the twin cores, Furong Town and Tianmen Mountain constitute the core points of the network structure, and the radiation drive of the core nodes is not pronounced.

Aiming at the problems of parameters to be modified and the indistinct physical meaning of the photoelectric stabilization platform control based on the principle of active disturbance rejection, a sliding mode active disturbance rejection control algorithm is proposed. The mathematical model of the control system of the two-axis optoelectronic stabilization platform is established. The external disturbance and various order states of the airborne optoelectronic stabilization platform are estimated in actual time by using the extended state observer, and the optimal control function is constructed by the sliding mode reaching law to complete the nonlinear reactive reactance. The optimization of the disturbance controller structure is carried out, and the algorithm is verified by Matlab simulation. The simulation results show that after the photoelectric stabilization platform adopts the sliding mode ADRC controller, it not only retains the advantages of strong nonlinear ADRC resistance to load disturbance, but also can effectively suppress the external disturbance and realize the high-precision position of the photoelectric stabilization platform control.

Object detection based on the convolutional neural network requires a large of datasets for training to achieve good results. However, it is labor-intensive or unrealistic to prepare such high-quality training data in most industrial applications. Recently, one-shot object detection task was proposed aiming to tackle this challenging problem by using only one sample for reference. In this work, a new framework named SimDet based on Faster R-CNN has been proposed for one-shot object detection. Specifically, query and target image features are extracted through a Siamese network, and target features are enhanced in where has high similarity with query feature. In order to solve the problem of RPN learning difficulty with one sample, we propose a new module of Cross Similarity Module, which focuses more on the difference between query and support rather than the feature itself. Furthermore, we design a similarity loss for learning the cross similarity between target feature and query feature. Finally, the extensive experiments show that our model achieves state-of-the-art performance on PASCAL VOC under one-shot setting of detecting objects from both seen and novel classes and on MS COCO from seen classes.

Purpose To investigate the current status of marriage and fertility of patients with epilepsy (PWE) and characterize its influencing factors. Methods A total of 1,823 adult patients (males age 22 years or older, females age 20 years or older) were included in this study. Data concerning sociodemographic and clinical characteristics were collected. Descriptive analyses, followed by univariate and multivariate logistic regression analyses were utilized to examine factors associated with marriage and fertility of PWE. Marital status of PWE was compared with Chinese population. Standardized marriage rate (SMR) for age and sex was estimated based on the 2010 sixth national population census. Results 1,132 patients (62.1%) were married and 823 (45.1%) had a history of fertility. Patients had lower marriage rates than Chinese population (62.1% vs 78.4%). Patients with adult-onset epilepsy (>18 years) had a significantly higher rate of marriage and fertility (p ＜ 0.001) compared to those with childhood-onset epilepsy (≤18 years). Employed patients had higher marriage rates than unemployed patients (64.9% vs 58.6%, p = 0.006), with only male patients being significantly affected by employment status (p ＜ 0.001). Multiple logistic regression revealed that age, age at first seizure onset, and employment status were related to both marriage and fertility. Conclusion Epilepsy had negative effects on marriage and fertility status. Marriage and fertility rates were lower in patients with Childhood-onset epilepsy (≤18 years). Furthermore, employment status mainly affected the marriage rate of male patients.

Continuous carbon-fibre-reinforced poly-ether-ether-ketone (CCF/PEEK) composites have garnered particular attention owing to the excellent thermal-assistance, corrosion-assistance and mechanical properties. In this study, CCF/PEEK composites were first prepared by extrusion three-dimensional (3D) printing. Interlayer delamination as a major factor limits the performance of thermoplastics extrusion 3D printing, and is exacerbated owing to the introduction of continuous fibres in this process. To overcome the interlayer delamination, the impregnation behaviours between carbon fibre tow and PEEK were studied by adjusting the viscosity of matrix materials and implementing pre-impregnation, while the interlayer bonding behaviours in different laser preheating temperatures were studied subsequently. Sufficient impregnation and the improved interlayer bonding of CCF/PEEK composites was effectively realised. The interlaminar shear strength and flexural strength of the CCF/PEEK composites can reach over 35 MPa and 480 MPa respectively, which gives a promising candidate for the preparation of complex structural parts in aviation and aerospace as a metal replacement.

People with epilepsy (PWE) have an increased suicide prevalence. This study aimed to identify the risk factors for suicidal tendency among PWE in West China. A nested case–control study was designed in a cohort of patients with epilepsy (n = 2087). In total, 28 variates were calculated. In the univariate analysis, unemployment, low income, seizure frequency, seizure-free time, infectious or structural etiology, levetiracetam or phenobarbital use, anxiety, depression, and stigma were associated with suicidal tendency. A multivariate analysis indicated that unemployment (odds ratio [OR] 5.74, 95% confidence interval [CI] 2.13–15.48), levetiracetam use (OR 2.80, 95%CI 1.11–7.05), depression (C-NDDI-E score ≥ 13; OR 3.21, 95%CI 1.26–8.21), and stigma (SSCI score ≥ 16; OR 6.67, 95%CI 1.80–24.69) were independently associated with suicidal tendency. Conditional inference tree analysis indicated that SSCI and C-NDDI-E scores could effectively identify patients with suicidal tendency. Thus, this study suggests that unemployment, levetiracetam use, depression, and stigma are independent risk factors for suicidal tendency in PWE in China.

The objective of the study was to design a clinically useful tool to predict the risk of seizure-related motor vehicle accidents (MVAs) for people with epilepsy (PWE). Participants were patients who visited our epilepsy center in West China Hospital from October 2012 to October 2019 and were divided into a primary cohort and a validation cohort. Ultimately, we included 525 patients in the primary cohort and 86 patients in the validation cohort. Proportional hazard regression was performed to measure the prognostic factors of car accidents. The outcome was used to create a nomogram model. The final model had 7 factors, with a C-index of 0.85 (95% CI, 0.80-0.91), to predict the possibility of non-MVA for PWE. For the validation cohort, the C-index was 0.83 (95% CI, 0.72-0.95). This nomogram model can offer more individualized advice to PWE who are still driving by estimating the risk of car accidents.

Temporal lobe epilepsy (TLE) is the most common type of intractable epilepsy in adults. A novel method based on the ratio of T1-weighted (T1w) and T2-weighted (T2w) magnetic resonance images can investigate brain microstructural changes and how these regional changes interact with each other. This study estimated T1w/T2w ratios in 42 left TLE (LTLE) and 42 right TLE (RTLE) patients and 41 healthy controls (HC). A T1w/T2w structural covariance network (SCN) was built by calculating correlations between any two regions across subjects and analysed by graph theory. Voxel-wise comparisons of T1w/T2w laterality were performed among the three groups. Compared to HC, both patient groups showed decreased T1w/T2w in frontotemporal regions, amygdala and thalamus; however, the LTLE showed lower T1w/T2w in left medial temporal regions than RTLE. Moreover, the LTLE exhibited decreased global efficiency compared with HC and more increased connections than RTLE. The laterality in putamen was differently altered between the two patient groups: higher laterality at posterior putamen in LTLE and higher laterality at anterior putamen in RTLE. This study demonstrated T1w/T2w reductions in frontotemporal and subcortical regions and extensive disconnections of SCN, providing evidence that TLE is a system disorder with widespread disruptions at regional and network levels. The putamen may play a transfer station role in damage spreading induced by epileptic seizures from the hippocampus.

Epilepsy and depression were proposed to facilitate each other reciprocally through common neurobiological anomalies, especially the prefrontal-limbic-subcortical abnormalities. Yet neuroimaging patterns of higher-order cognitive networks and neuroanatomical correlates were rarely compared in temporal lobe epilepsy patients with (TLE-D) and without depression (TLE-N). We collected T1-weighted structural and resting-state functional MRI data from 20 TLE-D, 31 TLE-N and 20 healthy controls (HCs) and performed analyses including hippocampal volume (HCV), cortical thickness, gray matter volume (GMV) and whole-brain functional network connectivity (FNC) across three groups. Imaging differences were related to clinical and psychological measurements. TLE-D demonstrated disrupted functional role of subcortical (SUB) and higher-order cognitive networks compared to TLE-N and HCs. In TLE-D, GMV in the right supplementary motor area (SMA) and FNC between the dorsal attention (DAN) and SUB were attenuated compared to TLE-N and HCs, FNC between SUB and the visual network (VIS) decreased compared to HCs. GMV in the right SMA was negatively correlated with depression severity and some symptoms. Combined, explicit emotion regulation may be impaired in TLE-D. Meanwhile, compared to HCs, TLE-N showed smaller HCVs, TLE-D and TLE-N showed smaller GMV in the medial orbital frontal gyrus and right hippocampus and hippocampal gyrus, possibly implying predisposition of epileptic activities to co-morbid depression. Our findings suggest distinct anatomical and FNC patterns in TLE-D and TLE-N. More than prefrontal-limbic-subcortical anomalies, disrupted higher-order cognitive network may contribute to depression in TLE, providing new potential treatment targets for depression and calling attention to relation between cognitive dysfunction and co-morbid depression.

Objectives To explore the dynamic changes of gray matter volume and intrinsic brain activity following anterior temporal lobectomy (ATL) in patients with unilateral mesial temporal lobe epilepsy (mTLE) who achieved seizure-free for two years. Materials & methods High-resolution T1-weighted MRI and resting-state functional MRI data were obtained in ten mTLE patients at five serial time points: before surgery, three months, six months, 12 months and 24 months after surgery. The gray matter volume (GMV) and amplitude of low-frequency fluctuations (ALFF) were compared among the five scans to depict the dynamic changes after ATL. Results After successful ATL, GMV decreased in several ipsilateral brain regions: ipsilateral insula, thalamus and putamen showed gradual gray matter atrophy from 3 to 24 months, while ipsilateral superior temporal gyrus, middle temporal gyrus, inferior temporal gyrus, middle occipital gyrus, inferior occipital gyrus, caudate nucleus, lingual gyrus and fusiform gyrus showed significant GMV decrease at 3 months follow-up, without further changes. Ipsilateral insula showed gradual ALFF decrease from 3 to 24 months after surgery. Ipsilateral superior temporal gyrus showed ALFF decrease at 3 months follow-up, without further changes. Ipsilateral thalamus and cerebellar vermis showed obvious ALFF increase after surgery. Conclusions Surgical resection may lead to a short-term reduction of gray matter volume and intrinsic brain activity in neighboring regions, while the progressive gray matter atrophy may be due to possible intrinsic mechanism of mTLE. Dynamic ALFF changes provide evidence that disrupted focal spontaneous activities were reorganized after successful surgery.

Separating and recovering CHF3 and CHClF2 greenhouse gases from exhausted gases is quite important for avoiding adverse impacts to the environment. In synthesizing chlorofluorocarbons substitutes, faujasite (FAU) is proved to be effective in separating the hydrofluorocarbons. Grand canonical ensemble Monte Carlo simulations were used without precedent in analyzing the competitive adsorption mechanism of CHF3/CHClF2 in Na58Al58Si134O384 (58Al), Na88Al88Si104O384 (88Al), and Na96Al96Si96O384 (96Al) FAU zeolite model from infinite dilution to saturation adsorption, so as to explore the overall competitive relationship as the adsorption amount increases. As a result, it has been found that the sodium migration degree is affected by the guest–host effect in the 58A1 model. However, the sodium migration is not discovered in 88Al and 96Al models with diversified CHF3 or CHClF2 loadings. The preferred binding site in all FAU zeolite models involves CHClF2 and CHF3 anchored by cations in sites II and site III′. Ad...

The separation and recovery of the greenhouse gases CHF3 and CHClF2 from emissions is essential to avoid adverse environmental effects. Nanoporous carbons are excellent candidates for the capture of CHF3. However, little research has been done on the effect of pore size on the adsorption capacity and selectivity of CHClF2 over CHF3 in nanoporous carbon materials. The effect of the pore size on the competitive adsorption of a binary CHF3–CHClF2 mixture in graphitic slit pores has been investigated using a combination of Monte Carlo simulations and breakthrough curve experiments over a wide range of pressures and temperatures. The entropy changes have a considerable effect on selectivity of CHClF2 over CHF3 because the size of the adsorbate molecule is close to the effective height of the pores; conversely, adsorption energy has a significant impact. The selectivity of CHClF2 over CHF3 at 0.05–1.0 MPa increases in the order 19.47 < 16.62 < 13.20 < 11.77 < 8.30 < 5.17 < 5.67 A. The mechanisms for adsorption ...

Pressure swing adsorption (PSA) is a very versatile, albeit complex gas separation and purification technology. Due to its complexity and periodic operation, calculation of the optimal PSA system that simultaneously obtains process design and control decision variables is a complicated task. This work presents detailed design and control optimization study of a two-bed, six-step PSA system aimed at heavy component CH4 upgrading. The key optimization objective is to enhance product CH4 recovery while achieving a closed loop product CH4 purity of 75% for separating 68%N2/32%CH4 feed under external disturbances. Traditional sequential and simultaneously design and control approach are employed and compared based on this purpose. The benefits of simultaneous methodology over conventional sequential approach are successfully demonstrated by closed-loop performance results and simulation profiles. The simultaneously design and control methodology has succeeded in synthesizing the optimal PSA cycle which can generate CH4 recovery as high as 97.30%.

Enrichment of bromine from brine using a PTFE hollow fiber-based supported gas membrane (SGM) process was studied. The experimental data demonstrated that the overall mass transfer coefficient obtained for feed containing Cl − such as real brine was much smaller than that for a simple aqueous bromine solution, which was mainly due to the association of Br 2 with Cl − in the brine. Based on the stronger association between Br 2 and Br − than that of Br 2 and Cl − , NaBr instead of NaOH was selected as an absorbent for enrichment of bromine from brine. The results showed that NaBr as absorbent for enriching bromine using the SGM process was feasible and bromine could be enriched for > 14 times. Conventional distillation could be further applied to regenerate the stripping solution used, and a bromine-enriched stream was obtained as a raw product. A mathematical model was established to characterize the mass transfer of bromine when brine containing chloride ions was used as feed and NaBr or NaOH served as absorbents and the association between Br 2 and Br − or Cl − was considered. The lab and pilot-scale study demonstrated that the PTFE membrane contactor was stable for a long-term operation of > 12 months.

Trifluoromethane (R23), a ubiquitous byproduct of chlorodifluoromethane (R22) synthesis, is one of the most potential greenhouse gases. The encouraged approach is thermal oxidation to process the vent gas by the clean development mechanism (CDM). Though such an approach could avoid the adverse environmental impacts, it will result in a great economic loss that includes not only the incineration cost but also the waste resource of R23. R23 is valuable as a refrigerant, fire suppression agent, and plasma etchant (purity: 99.999 mol %). In this work, the distillation-pressure swing adsorption (DIST-PSA) process was employed to concentrate R23 from 88% to 99.999% in the vent gas economically. Dynamic breakthrough experiments were performed to predict the adsorbent separation performance. Results indicated the coconut activated carbon (SAC-1) is appropriate material for R23 and R22 separation. The SAC-1 has a high separation factor value for R22 and R23 under the experimental conditions. Afterward, the DIST-PS...

Fabric defect detection plays an important role in the production of fabrics. Thanks to deep learning and large-scale datasets, popular object detection tasks have made great progress. RetinaNet has been widely used in object detection tasks in various fields, such as face detection, due to its flexibility and operability. It's high accuracy and detection results are derived from datasets with rich features. So limited by the small-scale fabric defect dataset, RetinaNet is difficult to apply to fabric defect detection task. In this paper, we propose an effective neural network approach to solve the problem of small-scale fabric dataset and apply RetinaNet to this task. To overcome the insufficient features because of the small-scale dataset, we first propose a generative model to add Gaussian noise on latent space, called focus generator, which can be controlled with defect instances to generate more data. Then we add a classification model to limit influence produced by the focus generator, called score classification. Finally, we merge the focus generator and score classification with an improved RetinaNet to achieve fabric defect detection, therefore, we name our model FSR. By the way, the operations of adding noise are different on the steps of training and testing. The experimental result shows that our proposed method can achieve better performance comparing to our baseline RetinaNet and finally achieve accuracy of 83.4% on our small-scale fabric defect dataset.

Fashion landmark detection is a fundamental problem in visual fashion analyze, which aims at locating the precise coordinates of functional key points defined on clothes. Dozens of deep learning-based methods are proposed to address this problem. How to extract adequate and effective features is a critical point for this challenging task. In this paper, we propose the Dual Attention Feature Enhancement(DAFE) module, which strengthens the extracted features by adaptively reusing low-level image details and emphasizing informative parts. First, DAFE enhances the pixel-wise information through capturing the spatial details from low-level features by the guidance of attention matrix, which is generated from high-level ones. Second, DAFE emphasizes task-related features by modeling long-range relationships between channels. Experimental experiments on Deepfashion and FLD datasets demonstrate that our method achieves state-of-the-art performance, and our approach also achieves competitive results on Deepfashion2 Landmark Estimation Challenge.

Highlights • Postoperative changes of contralateral hippocampus in temporal lobe epilepsy. • No obvious hippocampal volume change was observed after successful surgery. • Surgical manipulation may lead to a transient functional connectivity reduction. • Increased functional connectivity mostly involved bilateral frontal regions., Objective To explore the structural and functional reorganization of contralateral hippocampus in patients with unilateral mesial temporal lobe epilepsy (mTLE) who achieved seizure-freedom after anterior temporal lobectomy (ATL). Methods We obtained high-resolution structural MRI and resting-state functional MRI data in 28 unilateral mTLE patients and 29 healthy controls. Patients were scanned before and three and 24 months after surgery while controls were scanned only once. Hippocampal gray matter volume (GMV) and functional connectivity (FC) were assessed. Results No obvious GMV changes were observed in contralateral hippocampus before and after successful surgery. Before surgery, ipsilateral hippocampus showed increased FC with ipsilateral insula (INS) and temporoparietal junction (TPJ), but decreased FC with widespread bilateral regions, as well as contralateral hippocampus. After successful ATL, contralateral hippocampus showed: (1) decreased FC with ipsilateral INS at three months follow-up, without further changes; (2) decreased FC with ipsilateral TPJ, postcentral gyrus and rolandic operculum at three months, with an obvious increase at 24 months follow-up; (3) increased FC with bilateral medial prefrontal cortex (MPFC) and superior frontal gyrus (SFG) at three months follow-up, without further changes. Conclusions Successful ATL may not lead to an obvious structural reorganization in contralateral hippocampus. Surgical manipulation may lead to a transient FC reduction of contralateral hippocampus. Increased FC between contralateral hippocampus and bilateral MPFC and SFG may be related to postoperative functional remodeling.

The removal and enrichment of aliphatic amines with low molecular weights from their individual aqueous solutions was investigated theoretically and experimentally via a hollow-fiber supported-gas-membrane (SGM) process. Aqueous solutions containing 200–5000 mg L −1 amine were tested as feed, and an aqueous solution of 10 wt% sulfuric acid was used as an absorbing solution. Amines such as methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine and triethylamine, as well as ammonia, were tested in the SGM process. The experimental data demonstrated that the overall mass transfer coefficient was a strong function of the polarity of the amine or amine/water volatility and was not a simple function of the molecular weight or boiling point of amines; the order was determined to be trimethylamine>ammonia>triethylamine>diethylamine>ethylamine>dimethylamine>methylamine. The influences on mass transfer coefficients of the feed-in temperature, feed-in concentration, feed flow rate, and the concentration of NaOH pre-added to the feed were also investigated. Among these operating factors, the feed-in temperature and NaOH concentration were crucial; increasing the feed-in temperature and the NaOH concentration led to a significant increase in the mass transfer coefficient, especially when the amine concentration in the feed was low. Mathematical models incorporating laminar flow, ion and molecular diffusion, dissociation equilibrium and vapor–liquid equilibrium were established and solved numerically. When the surface tension of the feed solution was >45 mN m −1 , the SGM process demonstrated good stability during a test period of at least 30 days. Greater than 95% of the amine was recovered, and the amine could be enriched by >20 times in the absorbing solution. Thus, this SGM-based separation process is suitable to remove, recover, and concentrate amines from their aqueous solutions.

In order to remove and recover urea from its dilute aqueous solutions, e.g., wastewater drained from urea synthesis plants, continuous-effect membrane distillation (CEMD) process providing an extremely high thermal efficiency was investigated to concentrate aqueous solution containing urea. By using an air-gap membrane distillation module fabricated with both porous hydrophobic hollow fibers and dense-wall hollow fibers, the CEMD operation-mode can easily realize the direct recovery of condensation heat of the permeate to preheat the cold feed in situ within a single module. A series of experiments were conducted to evaluate the performance of CEMD process in terms of permeation flux (Jw), gain output ratio (GOR) and rejection factor (Rf) under various operating conditions, such as the feed-in concentration, cold feed-in temperature, heated feed-in temperature and feed flow rate. The maximum values of GOR = 14.0, Jw = 6.8 L h−1 m−2 and Rf = 99.99% were achieved respectively. When a feed solution of 1.0 wt% urea was used as a sample wastewater, the feed could be at least concentrated to 40 wt% with high values of GOR, Jw and Rf. The experimental data showed that the mild operation condition could also help to avoid the urea loss from its thermal hydrolysis. A brief theoretical model was introduced and used to discuss experimental results.

The separation and recovery of the greenhouse gases CHF3 and CHClF2 from emissions is essential to avoid adverse environmental effects. Faujasite has shown its credibility in separation of hydrofluorocarbons during the synthesis of chlorofluorocarbons substitutes. Investigation of adsorption site and energy about CHClF2 and CHF3 on zeolite is essential to understand the process of adsorption separation of CHClF2 and CHF3 mixtures. However, the underlying adsorption mechanism of CHClF2 and CHF3 on zeolite is not yet understood at the molecular level. A new force field was developed for CHClF2 and CHF3 and applied to the adsorption of these species on NaX using Monte Carlo simulations. The preferred binding site on NaX involves CHClF2 and CHF3 anchored by both site II and site III’ (III) cations. Adsorption enthalpy predicted is highly correlated upon adsorption site and geometry structure of CHClF2 and CHF3 on NaX. The CHF3 is preferentially adsorbed on NaX for CHClF2 and CHF3 adsorption, owing to short-range force of CHF3 hydrogen center with the lattice oxygen of the supercage, which is confirmed by FT-IR results. This research helps elucidate a molecular mechanism for the adsorption of CHClF2 and CHF3 on NaX, which contributes to understanding adsorption separation processes for the of CHClF2 and CHF3 on zeolites.

In order to improve the inter-line bonding performance of 3D printed continuous fiber reinforced composites, an innovative sinusoidal-path extrusion 3D printing method was proposed. Conventional 3D printing constructs components from stacks of individual extruded straight lines and flat layers, resulting in the relatively weak bonding that occurs between individual lines and layers and is aggravated due to the introduction of continuous fibers. The influence of structural parameters (amplitude & frequency) on the inter-line tensile properties and fracture patterns of sinusoidally 3D printed composites were systematically investigated. The results showed that as the amplitude and frequency of the sinusoidal path increased, the inter-line tensile strength, tensile modulus and fracture energy absorption of CCF/PLA composites increased 95.4%, 57.3% and 165%, respectively. Based on this study, a non-planar sinusoidal layer extrusion 3D printing method of CFRTPCs was proposed, which provides a new idea for comprehensive control of the anisotropy of 3D printed composites.

3D printed continuous carbon fiber reinforced PEEK (CCF/PEEK) composites have got much attention because of their excellent mechanical, thermal and chemical performance and the formability of complex structural components. However, there are always two different weak-bond interfaces limiting the application of the composites critically, which are the poor interlayer bond and the weak interface between carbon fibers and PEEK. A plasma-laser cooperatively assisted 3D printing process was utilized to improve the bi-scale interface. After optimizing, the interlaminar shear strength can be improved from 5.78 MPa to 39.05 MPa. After analyzing the failure mode and bi-scale interfacial bond mechanism, it’s found that the laser mainly improves the interlayer bond and crystallinity, while the plasma effectively improves the mechanical modulus by treating the surface of the carbon fibers chemically and physically. The work provides a really novel idea for developing the 3D printed CCF/PEEK composites for further application in aerospace and automotive industries.

Background Previous neuroimaging studies have revealed aberrant basal ganglia-thalamocortical circuit in patients with paroxysmal kinesigenic dyskinesia (PKD) with drug treatment. This study aims to investigate the topological organization of functional networks in drug-naive PKD. Methods Resting-state functional magnetic resonance imaging (rs-fMRI) was performed in 24 drug-naive PKD patients and 24 age, gender and mean framewise displacement (FD)-matched healthy controls (HCs). The network topological properties (including global and nodal measures) were analyzed between two groups by using graph-based theoretical approaches. Pearson's correlation analysis was performed between significant metrics and duration of disease and the age of onset of patients with PKD. Results Compare to HCs, the drug-naive PKD patients showed increased nodal centralities mainly in left precentral gyrus, basal ganglia and limbic regions and decreased nodal centralities in the temporal pole. Our results showed that drug-naive PKD patients presented the small-world topology and at the global level no significant differences were found between PKD and HCs. In the correlation analysis, the increased nodal efficiency in the left pallidum was positively correlated with the onset of age. Conclusions Our findings supported the previous observation of the disruptive cortical-basal ganglia circuitry in PKD patients, but difference in that the prominent change of precentral area and temporal pole were also observed in our study when the potential impact of drug was excluded. These findings may provide a novel insight into further delineation of the pathophysiological genesis and possible target for PKD.

BACKGROUND A major cost in acid-catalysed hydrolysis of biomass to fermentable sugars is the consumption of acid itself. In this study, a combined process was developed in which the acid and sugar in the hydrolysate were separated using an acid retardation process and then the dilute aqueous product streams were concentrated using a continuous-effect membrane distillation (CEMD) process, thus acid could be reused as catalyst. RESULTS The recovery rate of sugar was as high as 94.3–99.2% while the recovery rate of sulfuric acid was 92.4–98.9%. The eluents were further concentrated using the CEMD process. When a solution of 2 wt% sulfuric acid was concentrated to c. 40 wt%, the maximum value of permeation flux (Jw) and gained output ratio (GOR) was 6.20 L m−2 h−1 and 15.50, respectively. Meanwhile, the dilute aqueous sugar solution obtained from corn stover was concentrated 20-fold to a final concentration of c. 497.6 g L−1 using the CEMD process with a final GOR of 5.5. CONCLUSION The combination of acid retardation and CEMD is suitable for the production of sugar, further purification and concentration of eluents; the sugar solution can be used for fermentation and acid solution can be reused as catalyst. © 2015 Society of Chemical Industry

In the present work, continuous-effect membrane distillation (CEMD) process with a function of in-situ internal latent-heat-recovery was applied to concentrate aqueous glycerol solution by using a hollow fiber air-gap membrane distillation module. Compared with other conventional membrane distillation processes, the CEMD process enabled higher energy efficiency and lower operational cost, and thus greater potential commercializing application. The deep-concentrating experiments revealed that a feed of 10 g/L could be successfully concentrated up to about 400 g/L with a rejection efficiency still greater than 99.9%. The maximum value of gain output ratio ( GOR ) experimentally obtained could reach 16.2, and even though the glycerol concentration was up to about 350 g/L, the GOR value could still be 5.3, which corresponded to the energy efficiency of a conventional seven-effect evaporator. When the feed was concentrated up to around 300 g/L, the GOR and the trans-membrane flux ( J w ) decreased sharply. The increment of glycerol viscosity and the reduction of water vapor pressure resulted from the increase of feed concentration were the critical reasons that led to deterioration in GOR and J w . Four-factor two-level full factorial analysis showed that for a certain feed-in concentration, the heated feed-in temperature was the most significant factor to obtain higher GOR and J w . The value of GOR and J w basically maintained invariable in the long-term stability test lasting for 60 days, which demonstrated that CEMD process was suitable for concentrating aqueous glycerol solution in a high-efficiency and energy-saving way.

Notch signaling is involved in an intercellular communication mechanism that is essential for coordinated cell fate determination and tissue morphogenesis. The biological effects of Notch signaling are context-dependent. We investigated the functional and hierarchical relationship between angiotensin (Ang) II receptor signaling and Notch signaling in vascular smooth muscle cells (VSMCs). A fluorogenic substrate assay revealed directly that the enzymatic activity of γ-secretase was enhanced after 10 min of Ang II stimulation in HEK293 cells expressing Ang II type 1 receptor. Notch cleavage by γ-secretase was consistently induced and peaked at 10 min after Ang II stimulation, and the Ang II-stimulated increase in Notch intracellular domain production was significantly suppressed by treatment with the γ-secretase inhibitor DAPT. Treatment with DAPT also significantly reduced the Ang II-stimulated proliferation and migration of human aortic VSMCs, as revealed by BrdU incorporation and the Boyden chamber assay, respectively. Systemic administration of the γ-secretase inhibitor dibenzazepine reduced Ang II-induced medial thickening and perivascular fibrosis in the aortas of wild-type mice. These findings suggest that the hierarchical Ang II receptor-Notch signaling pathway promotes the proliferation and migration of VSMCs, and thereby contributes to the progression of vascular remodeling.

Multiple-effect membrane distillation (MEMD) process, by using a hollow fiber-based AGMD module and an external heat exchanger, was studied to concentrate dilute sulfuric acid solution. Latent heat of distillate was in-situ recovered by directly heating the cold feed within the AGMD module of special configuration. Permeation flux (Jw) and performance ratio (PR) parameters were used to characterize the operation performance of MEMD process. PR value obtained in the MEMD process was much higher than that obtained in traditional and the other modified membrane distillation process. The effects of heated feed-in temperature, cold feed-in temperature, feed-in flow rate and feed-in concentration on the MEMD performance were experimentally investigated. The dilute sulfuric acid in 2 wt.% could be concentrated up to about 40 wt.% by using MEMD process. The maximum value of PR and Jw could reach 11.5 and 5.3 L/m2h, respectively. When the feed concentration was up to 20 wt.%, the value of PR and Jw could still be 4.9 and 1.9 L/m2h, respectively. In a long-term stability test lasting for > 30 days, the electrical conductivity of the distillate was always less than 150 μs/cm, which demonstrated that the performance of MEMD modules was kept in good condition.

A continuous-effect membrane distillation (CEMD) process was developed by equipping air gap membrane distillation (AGMD)-based and strictly-parallel hollow fiber module with internal heat recovery. Its performance was indicated by flux, performance ratio and evaporation efficiency. Two kinds of CEMD modules made from different membrane fibers were tested. A face-centered central composite experimental design was conducted to investigate the influences of operating variables including cold-feed temperature, hot-feed temperature, and feed-in flow rate on the performance. Within the studied experimental range, the maximum PR of 13.8 was obtained. A theoretical model based on governing transport equations was established to predict the process performance, and the model described the experimental data fairly well. In light of the model, possible ways to further increase PR were predicted. The dilute aqueous sugar solution was successfully concentrated 12-fold to a final concentration of about 20 wt % by using CEMD process with a final PR of 8.2. © 2012 American Institute of Chemical Engineers AIChE J, 59: 1278–1297, 2013

Multiple-effect membrane distillation (MEMD) using a hollow fiber-based air-gap membrane distillation module was experimentally examined for concentrating dilute aqueous hydrochloric acid. The effects of the hot and cold feed-in temperatures, and the feed-in volumetric flow rates on the performance of the MEMD process were studied. The performance was evaluated using the performance ratio (PR), the average selectivity of water over HCl (βavg) and the permeation flux (N). Two types of porous fibers made from polypropylene were used to fabricate the MEMD modules. The experimental data indicated that hollow fibers with high porosity were preferred for the MEMD process. The PR, βavg and N all decreased as the feed concentration increased. When the feed concentration was below 12 wt-%, the PR was 6.0–9.6 and βavg was 10–190. When the concentration of HCl reached 18 wt-%, the PR and βavg were about 4.4 and 2.3, respectively. However, βavg sharply decreased to around 1.0 when the feed was further concentrated. During an operational stability test that lasted for 30 days, the performance of the MEMD modules remained good.

The activation of renin-angiotensin system contributes to the development of metabolic syndrome and diabetes as well as hypertension. However, it remains undetermined how renin-angiotensin system is implicated in feeding behavior. Here, we show that angiotensin II type 1 (AT(1)) receptor signaling regulates the hypothalamic neurocircuit that is involved in the control of food intake. Compared with wild-type Agtr1a(+/+) mice, AT(1) receptor knock-out (Agtr1a(-/-)) mice were hyperphagic and obese with increased adiposity on an ad libitum diet, whereas Agtr1a(-/-) mice were lean with decreased adiposity on a pair-fed diet. In the hypothalamus, mRNA levels of anorexigenic neuropeptide corticotropin-releasing hormone (Crh) were lower in Agtr1a(-/-) mice than in Agtr1a(+/+) mice both on an ad libitum and pair-fed diet. Furthermore, intracerebroventricular administration of CRH suppressed food intake both in Agtr1a(+/+) and Agtr1a(-/-) mice. In addition, the Crh gene promoter was significantly transactivated via the cAMP-responsive element by angiotensin II stimulation. These results thus demonstrate that central AT(1) receptor signaling plays a homeostatic role in the regulation of food intake by maintaining gene expression of Crh in hypothalamus and suggest a therapeutic potential of central AT(1) receptor blockade in feeding disorders.

Type 1 angiotensin II (AT(1)) receptor has a critical role in the development of load-induced cardiac hypertrophy. Recently, we showed that mechanical stretching of cells activates the AT(1) receptor without the involvement of angiotensin II (AngII) and that this AngII-independent activation is inhibited by the inverse agonistic activity of the AT(1) receptor blocker (ARB), candesartan. Although the inverse agonist activity of ARBs has been studied in terms of their action on constitutively active AT(1) receptors, the structure-function relationship of the inverse agonism they exert against stretch-induced AT(1) receptor activation has not been fully elucidated. Assays evaluating c-fos gene expression and phosphorylated extracellular signal-regulated protein kinases (ERKs) have shown that olmesartan has strong inverse agonist activities against the constitutively active AT(1) receptor and the stretch-induced activation of AT(1) receptor, respectively. Ternary drug-receptor interactions, which occur between the hydroxyl group of olmesartan and Tyr(113) and between the carboxyl group of olmesartan and Lys(199) and His(256), were essential for the potent inverse agonist action olmesartan exerts against stretch-induced ERK activation and the constitutive activity of the AT(1)-N111G mutant receptor. Furthermore, the inverse agonist activity olmesartan exerts against stretch-induced ERK activation requires an additional drug-receptor interaction involving the tetrazole group of olmesartan and Gln(257) of the AT(1) receptor. These results suggest that multivalent interactions between an inverse agonist and the AT(1) receptor are required to stabilize the receptor in an inactive conformation in response to the distinct processes that lead to an AngII-independent activation of the AT(1) receptor.

The angiotensin II type 1 (AT(1)) receptor is a G protein-coupled receptor that has a crucial role in the development of load-induced cardiac hypertrophy. Here, we show that cell stretch leads to activation of the AT(1) receptor, which undergoes an anticlockwise rotation and a shift of transmembrane (TM) 7 into the ligand-binding pocket. As an inverse agonist, candesartan suppressed the stretch-induced helical movement of TM7 through the bindings of the carboxyl group of candesartan to the specific residues of the receptor. A molecular model proposes that the tight binding of candesartan to the AT(1) receptor stabilizes the receptor in the inactive conformation, preventing its shift to the active conformation. Our results show that the AT(1) receptor undergoes a conformational switch that couples mechanical stress-induced activation and inverse agonist-induced inactivation.