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1.
Nanoscale ; 2024 May 24.
Article in English | MEDLINE | ID: mdl-38787730

ABSTRACT

The development of efficient and recyclable photocatalysts for organic synthesis is of great interest. This study presents the synthesis of triphenylamine-based porous aromatic frameworks (TPA-PAFs) in an alternating donor-acceptor (D-A) manner. The light absorption range and the optical band gaps of TPA-PAFs are effectively tuned by changing the electron acceptor units, which further determine their photocatalytic properties. As a result, TPA-PAFs exhibit excellent catalytic performance for the photosynthesis of benzimidazoles in high yields (up to 99%), broad substrate scope (18 examples), and good recyclability (up to 10 cycles). This work provides a feasible approach toward the facile design and synthesis of efficient and stable PAF-based photocatalysts, which further broadens the application of PAFs catalytic materials in photocatalytic organic synthesis.

2.
Angew Chem Int Ed Engl ; 63(18): e202402095, 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38450907

ABSTRACT

Constructing stable and efficient photocatalysts for H2O2 production is of great importance and is challenging. In this study, the synthesis of three photoactive cyclooctatetrathiophene (COTh)-based porous aromatic frameworks (COTh-PAFs) in an alternating donor-acceptor (D-A) fashion is presented. In combination with a triazine-derived electron acceptor, PAF-363 exhibits high efficiency for the photosynthesis of H2O2 with production rates of 11733 µmol g-1 h-1(with sacrificial agent) and 3930 µmol g-1 h-1 (without sacrificial agent) from water and oxygen under visible light irradiation. Experimental results and theoretical calculations reveal that the charge transfer positions and the O2 adsorption sites in PAF-363 are both concentrated on COTh fragments, which facilitate the H2O2 production through the oxygen reduction reaction (ORR) pathway. This work highlights that the rational design of COTh-PAFs with consideration of D-A direction, charge transfer positions, and O2 adsorption sites provides a feasible access to efficient H2O2 production photocatalysts.

3.
Neural Netw ; 174: 106236, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38518710

ABSTRACT

In speech enhancement tasks, local and non-local attention mechanisms have been significantly improved and well studied. However, a natural speech signal contains many dynamic and fast-changing acoustic features, and focusing on one type of attention mechanism (local or non-local) cannot precisely capture the most discriminative information for estimating target speech from background interference. To address this issue, we introduce an adaptive selection network to dynamically select an appropriate route that determines whether to use the attention mechanisms and which to use for the task. We train the adaptive selection network using reinforcement learning with a developed difficulty-adjusted reward that is related to the performance, complexity, and difficulty of target speech estimation from the noisy mixtures. Consequently, we propose an Attention Selection Speech Enhancement Network (ASSENet) with the innovative dynamic block that consists of an adaptive selection network and a local and non-local attention based speech enhancement network. In particular, the ASSENet incorporates both local and non-local attention and develops the attention mechanism selection technique to explore the appropriate route of local and non-local attention mechanisms for speech enhancement tasks. The results show that our method achieves comparable and superior performance to existing approaches with attractive computational costs.


Subject(s)
Learning , Speech , Reinforcement, Psychology , Reward , Noise
4.
Small Methods ; : e2301302, 2023 Dec 05.
Article in English | MEDLINE | ID: mdl-38050926

ABSTRACT

Atom economy is one of the main concerns for material synthesis. Here, the facile synthesis of Lewis acidic boron-containing porous organic polymers (B-POPs) via hydroboration polymerization reaction of commercially available borane dimethyl sulfide complex (BH3 ∙SMe2 ) with multi-alkynes under mild reaction conditions is presented. This new synthetic method for B-POPs has the advantage of high atom economy. The resulted porous alkenyl borane polymers (PABPs) have unique features such as high boron content, strong Lewis acidity, and high surface areas. Owing to the strong Lewis acid-base interactions, PABPs exhibit excellent adsorptive capacity toward triethylamine (up to 841 mg g-1 ) and pyridine (up to 1396 mg g-1 ) vapor.

5.
Transl Psychiatry ; 12(1): 52, 2022 02 03.
Article in English | MEDLINE | ID: mdl-35115488

ABSTRACT

Deep brain stimulation (DBS) of structures in the brain's reward system is a promising therapeutic option for patients with treatment-resistant depression (TRD). Recently, DBS of the habenula (HB) in the brain's anti-reward system has also been reported to alleviate depressive symptoms in patients with TRD or bipolar disorder (BD). In this pilot open-label prospective study, we explored the safety and clinical effectiveness of HB-DBS treatment in seven patients with TRD or BD. Also, local field potentials (LFPs) were recorded from the patients' left and right HB to explore the power and asymmetry of oscillatory activities as putative biomarkers of the underlying disease state. At 1-month follow-up (FU), depression and anxiety symptoms were both reduced by 49% (n = 7) along with substantial improvements in patients' health status, functional impairment, and quality of life. Although the dropout rate was high and large variability in clinical response existed, clinical improvements were generally maintained throughout the study [56%, 46%, and 64% reduction for depression and 61%, 48%, and 70% reduction for anxiety at 3-month FU (n = 5), 6-month FU (n = 5), and 12-month FU (n = 3), respectively]. After HB-DBS surgery, sustained improvements in mania symptoms were found in two patients who presented with mild hypomania at baseline. Another patient, however, experienced an acute manic episode 2 months after surgery that required hospitalization. Additionally, weaker and more symmetrical HB LFP oscillatory activities were associated with more severe depression and anxiety symptoms at baseline, in keeping with the hypothesis that HB dysfunction contributes to MDD pathophysiology. These preliminary findings indicate that HB-DBS may offer a valuable treatment option for depressive symptoms in patients who suffer from TRD or BD. Larger and well-controlled studies are warranted to examine the safety and efficacy of HB-DBS for treatment-refractory mood disorders in a more rigorous fashion.


Subject(s)
Deep Brain Stimulation , Depressive Disorder, Treatment-Resistant , Habenula , Depression/therapy , Depressive Disorder, Treatment-Resistant/therapy , Humans , Prospective Studies , Quality of Life , Treatment Outcome
6.
Neurosurg Focus ; 51(5): E2, 2021 11.
Article in English | MEDLINE | ID: mdl-34724646

ABSTRACT

OBJECTIVE: To provide better postoperative healthcare for patients with Parkinson's disease (PD) who received deep brain stimulation (DBS) surgery and to allow surgeons improved tracking of surgical outcomes, the authors sought to examine the applicability and feasibility of remote assessment using smartphones. METHODS: A disease management mobile application specifically for PD was used to perform the remote assessment of patients with PD who underwent DBS. Connection with patients was first established via a phone call or a social application, and instructions for completing the remote assessment were delivered. During the video-based virtual meeting, three nonmotor assessment scales measuring the quality of life and mental state, and a modified version of the Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale, part III (MDS-UPDRS III) measuring motor abilities were evaluated. After the assessment, a report and the satisfaction questionnaire were sent to the patient. RESULTS: Overall, 22 patients were recruited over a 4-week period. Among those, 18 patients completed the assessment on the mobile application. The mean duration was 41.3 minutes for video assessment and 17.5 minutes for nonmotor assessment via telephone. The mean estimated cost was 427.68 Chinese yuan (CNY) for an in-person visit and 20.91 CNY for a virtual visit (p < 0.001). The mean time estimate for an in-person visit was 5.51 hours and 0.68 hours for a virtual visit (p = 0.002). All patients reported satisfaction (77.78% very satisfied and 22.22% satisfied) with the virtual visit and were specifically impressed by the professionalism and great attitude of the physician assistant. The majority of patients agreed that the evaluation time was reasonable (50% totally agree, 44.44% agree, and 5.56% neither agree nor disagree) and all patients expressed interest in future virtual visits (61.11% very willingly and 38.89% willingly). No adverse events were observed during the virtual visit. CONCLUSIONS: Innovation in remote assessment technologies was highly feasible for its transforming power in the clinical management of patients with PD who underwent DBS and research. Video-based remote assessment offered considerable time and resource reduction for both patients and doctors. It also increased safety and was a well-accepted, favored tool. Finally, the results of this study have shown there is potential to combine remote assessment tools with real-life clinical visits and other telemedical technologies to collectively benefit the postoperative healthcare of patients with PD undergoing DBS.


Subject(s)
Deep Brain Stimulation , Parkinson Disease , Humans , Parkinson Disease/therapy , Pilot Projects , Quality of Life , Smartphone , Treatment Outcome
7.
Front Neurosci ; 15: 705483, 2021.
Article in English | MEDLINE | ID: mdl-34646117

ABSTRACT

Background: Deep brain stimulation (DBS) is a well-established treatment for a variety of movement disorders. Rechargeable cell technology was introduced to pulse generator more than 10 years ago and brought great benefits to patients. However, with the widespread use of rechargeable implanted pulse generators (r-IPGs), a new hardware complication, when charging the r-IPG has been difficult, was encountered. Objective: The aims of this study were to report five cases confronted with r-IPG charging difficulty postoperatively and to explore the predisposing factors and treatment strategies for this rare complication. Methods: We retrospectively reviewed our DBS patient database for those who were implanted with r-IPGs. From 2012, we identified a total of 1,226 patients, with five of them experiencing charging difficulties after surgery. Detailed patient profiles and clinical procedures were scrutinized and reviewed. Results: All the charging problems were resolved by reoperation. Cases 1 and 2 required their r-IPGs to be anchored to the muscle and fascia. Cases 3 and 4 had their r-IPGs inserted in the wrong orientation at the initial surgery, which was resolved by turning around the r-IPGs at the revision surgery. Case 5, in which we propose that the thick subcutaneous fat layer blocked the connection between the r-IPG and the recharger, required a second operation to reposition the r-IPG in a shallow layer underneath the skin. For all cases, the charging problems were resolved without reoccurrences to date. Conclusion: Our case series indicates a novel hardware complication of DBS surgery, which had been rarely reported before. In this preliminary study, we describe several underlying causes of this complication and treatment methods.

8.
Front Psychiatry ; 12: 674962, 2021.
Article in English | MEDLINE | ID: mdl-34248713

ABSTRACT

The habenula, located in the epithalamus, has been implicated in various psychiatric disorders including mood disorders and schizophrenia. This study explored the transient effects of deep brain stimulation in the habenula. Each of the four patients (two with bipolar disorder and two with schizophrenia) was tested with eight deep brain stimulation contacts. Patients were examined via transient electrical stimulation 1 month after deep brain stimulation surgery. The pulse width was 60 µs and the voltage ranged from 0 V to a maximum of 10 V, increasing in increments of 1 V. Each patient received stimulation at two frequencies, 60 and 135 Hz. A total of 221 out of 385 active trials elicited stimulation-induced effects. The three most common transient effects were numbness, heart rate changes, and pain. The incidence of numbness, heart rate changes, pain, and involuntary movements increased with the increase in stimulation voltage. Through contralateral stimulation, numbness was triggered in all parts of the body except the scalp. The obtained stimulus-response maps suggested a possible somatosensory organization of the habenula.

9.
Front Neurol ; 12: 812455, 2021.
Article in English | MEDLINE | ID: mdl-35126302

ABSTRACT

INTRODUCTION: Previous studies have shown that subthalamic nucleus (STN) and unilateral globus pallidus interna (GPi) are similarly effective in the deep brain stimulation (DBS) treatment of motor symptoms. However, the counterintuitively more common clinical application of STN DBS makes us hypothesize that STN is superior to GPi in the treatment of motor symptoms. METHODS: In this prospective, double-blind, randomized crossover study, idiopathic PD patients treated with combined unilateral STN and contralateral GPi DBS (STN in one brain hemisphere and GPi in the other) for 2 to 3 years were enrolled. The MDS UPDRS-III total score and subscale scores for axial and bilateral limb symptoms were assessed preoperatively and at 2- to 3-year follow-up in four randomized, double-blinded conditions: (1) Med-STN+GPi-, (2) Med-STN-GPi+, (3) Med+STN+GPi-, and (4) Med+STN-GPi+. RESULTS: Eight patients had completed 30 trials of assessment. Compared with the preoperative Med- state, in the Med-STN+GPi- condition, the cardinal symptoms in both sides of the body were all improved. In the Med-STN-GPi+ condition, symptoms of the GPi-stim limb were improved, while only tremor was improved on the ipsilateral side, although all axial symptoms showed aggravation. Compared with the preoperative Med+ state, in the Med+STN+GPi- state, cardinal symptoms were improved on both sides, except that tremor was worsened on the STN-stim side. In the Med+STN-GPi+ state, the overall motor symptoms were aggravated compared with the preoperative Med+ state. Most axial symptoms worsened at acute unilateral STN or GPi DBS onset, compared to both preoperative Med- and Med+ states. No side effects associated with this study were seen. CONCLUSIONS: Improvement in motor symptoms was greater in all sub-scores favoring STN. The effects of STN+ were seen on both sides of the body, while GPi+ mainly acted on the contralateral side.

10.
Sci Rep ; 10(1): 21395, 2020 12 07.
Article in English | MEDLINE | ID: mdl-33288787

ABSTRACT

Deep eutectic solvents (DES) formed by quaternary ammonium salts and hydrogen bond donors are a promising green alternative to organic solvents. Their high viscosity at ambient temperatures can limit biocatalytic applications and therefore requires fine-tuning by adjusting water content and temperature. Here, we performed a meta-analysis of the impact of water content and temperature on the viscosities of four deep eutectic solvents (glyceline, reline, N,N-diethylethanol ammonium chloride-glycerol, N,N-diethylethanol ammonium chloride-ethylene glycol), their components (choline chloride, urea, glycerol, ethylene glycol), methanol, and pure water. We analyzed the viscosity data by an automated workflow, using Arrhenius and Vogel-Fulcher-Tammann-Hesse models. The consistency and completeness of experimental data and metadata was used as an essential criterion of data quality. We found that viscosities were reported for different temperature ranges, half the time without specifying a method of desiccation, and in almost half of the reports without specifying experimental errors. We found that the viscosity of the pure components varied widely, but that all aqueous mixtures (except for reline) have similar excess activation energy of viscous flow [Formula: see text]= 3-5 kJ/mol, whereas reline had a negative excess activation energy ([Formula: see text]= - 19 kJ/mol). The data and workflows used are accessible at  https://doi.org/10.15490/FAIRDOMHUB.1.STUDY.767.1 .

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