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1.
Comput Biol Med ; 172: 108298, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38503095

ABSTRACT

Detection and segmentation of neural synapses in electron microscopy images are the committed steps for analyzing neural ultrastructure. To date, manual annotation of the structure in synapses has been the primary method, which is time-consuming and restricts the throughput of data acquisition. Recent studies have utilized a series of deformations based on a segmentation model for the detection and segmentation of transmission electron microscope images. However, the analysis of synaptic segmentation and statistics still lacks sufficient automation and high-throughput. Therefore, we developed a dual-channel neural network instance segmentation model with weighted top-down and multi-scale bottom-up schemes, which aid in accurately detecting and segmenting synaptic vesicles and their active zones within presynaptic membranes in complex environments. In addition, we proposed a masked self-supervised pre-training model based on the latest convolutional architecture to improve performance in downstream segmentation tasks. By comparing our model to other state-of-the-art methods, we determined its viability and accuracy. The applicability of our model is thoroughly demonstrated by distinct application scenarios for neurobiological research. These findings indicate that the dual-channel neural network could facilitate the analysis of synaptic structures for the advancement of biomedical research and electron microscope reconstruction techniques.


Subject(s)
Image Processing, Computer-Assisted , Neural Networks, Computer , Image Processing, Computer-Assisted/methods , Synapses , Microscopy , Automation
2.
Inorg Chem ; 63(9): 4364-4372, 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38373009

ABSTRACT

For the most commonly applied platinum-based catalysts of direct methanol fuel cells, the adsorption ability toward reaction intermediates, including CO and OH, plays a vital role in their catalytic activity and antipoisoning in anodic methanol oxidation reaction (MOR). Herein, guided by a theoretical mechanism study, a favorable modulation of the electronic structure and intermediate adsorption energetics for Pt active sites is achieved by constructing the triple-phase interfacial structure between tin oxide (SnO2), platinum (Pt), and nitrogen-doped graphene (NG). From the strong electronic exchange at the triple-phase interface, the adsorption ability toward MOR reaction intermediates on Pt sites could be efficiently optimized, which not only inhibits the adsorption of CO* on active sites but also facilitates the adsorption of OH* to strip the poisoning species from the catalyst surface. Accordingly, the resulting catalyst delivers excellent catalytic activity and antipoisoning ability for MOR catalysis. The mass activity reaches 1098 mA mg-1Pt, 3.23 times of commercial Pt/C. Meanwhile, the initial potentials and main peak for CO oxidation are also located at a much lower potential (0.51 and 0.74 V) against commercial Pt/C (0.83 and 0.89 V).

3.
IEEE J Biomed Health Inform ; 28(3): 1704-1715, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38194407

ABSTRACT

Diabetic retinopathy (DR), a microvascular complication of diabetes, is the leading cause of vision loss among working-aged adults. However, due to the low compliance rate of DR screening and expensive medical devices for ophthalmic exams, many DR patients did not seek proper medical attention until DR develops to irreversible stages (i.e., vision loss). Fortunately, the widely available electronic health record (EHR) databases provide an unprecedented opportunity to develop cost-effective machine-learning tools for DR detection. This paper proposes a Multi-branching Temporal Convolutional Network with Tensor Data Completion (MB-TCN-TC) model to analyze the longitudinal EHRs collected from diabetic patients for DR prediction. Experimental results demonstrate that the proposed MB-TCN-TC model not only effectively copes with the imbalanced data and missing value issues commonly seen in EHR datasets but also captures the temporal correlation and complicated interactions among medical variables in the longitudinal clinical records, yielding superior prediction performance compared to existing methods. Specifically, our MB-TCN-TC model provides AUROC and AUPRC scores of 0.949 and 0.793 respectively, achieving an improvement of 6.27% on AUROC, 11.85% on AUPRC, and 19.3% on F1 score compared with the traditional TCN model.


Subject(s)
Diabetes Mellitus , Diabetic Retinopathy , Adult , Humans , Middle Aged , Diabetic Retinopathy/diagnosis , Neural Networks, Computer , Machine Learning , Electronic Health Records
4.
Small ; 20(3): e2303192, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37712177

ABSTRACT

Modulating the electronic configuration of the substrate to achieve the optimal chemisorption toward polysulfides (LiPSs) for boosting polysulfide conversion is a promising way to the efficient Li-S batteries but filled with challenges. Herein, a Co/CoS2 heterostructure is elaborately built to tuning d-orbital electronic structure of CoS2 for a high-performance electrocatalyst. Theoretical simulations first evidence that Co metal as the electron donator can form a built-in electric field with CoS2 and downshift the d-band center, leading to the well-optimized adsorption strength for lithium polysulfides on CoS2 , thus contributing a favorable way for expediting the redox reaction kinetics of LiPSs. As verification of prediction, a Co/CoS2 heterostructure implanted in porous hollow N, S co-doped carbon nanocage (Co/CoS2 @NSC) is designed to realize the electronic configuration regulation and promote the electrochemical performance. Consequently, the batteries assembled with Co/CoS2 @NSC cathode display an outstanding specific capacity and an admirable cycling property as well as a salient property of 8.25 mAh cm-2 under 8.18 mg cm-2 . The DFT calculation also reveals the synergistic effect of N, S co-doping for enhancing polysulfide adsorption as well as the detriment of excessive sulfur doping.

5.
Small ; 20(22): e2307135, 2024 May.
Article in English | MEDLINE | ID: mdl-38126901

ABSTRACT

Achieving high catalytic activity with a minimum amount of platinum (Pt) is crucial for accelerating the cathodic hydrogen evolution reaction (HER) in proton exchange membrane (PEM) water electrolysis, yet it remains a significant challenge. Herein, a directed dual-charge pumping strategy to tune the d-orbital electronic distribution of Pt nanoclusters for efficient HER catalysis is proposed. Theoretical analysis reveals that the ligand effect and electronic metal-support interactions (EMSI) create an effective directional electron transfer channel for the d-orbital electrons of Pt, which in turn optimizes the binding strength to H*, thereby significantly enhancing HER efficiency of the Pt site. Experimentally, this directed dual-charge pumping strategy is validated by elaborating Sb-doped SnO2 (ATO) supported Fe-doped PtSn heterostructure catalysts (Fe-PtSn/ATO). The synthesized 3%Fe-PtSn/ATO catalysts exhibit lower overpotential (requiring only 10.5 mV to reach a current density of 10 mA cm- 2), higher mass activity (28.6 times higher than commercial 20 wt.% Pt/C), and stability in the HER process in acidic media. This innovative strategy presents a promising pathway for the development of highly efficient HER catalysts with low Pt loading.

6.
Environ Res ; 235: 116645, 2023 10 15.
Article in English | MEDLINE | ID: mdl-37442263

ABSTRACT

Bioelectrochemical system is considered as a promising approach for enhanced bio-dechlorination. However, the mechanism of extracellular electron transfer in the dechlorinating consortium is still a controversial issue. In this study, bioelectrochemical systems were established with cathode potential settings at -0.30 V (vs. SHE) for trichloroethylene reduction. The average dechlorination rate (102.0 µM Cl·d-1) of biocathode was 1.36 times higher than that of open circuit (74.7 µM Cl·d-1). Electrochemical characterization via cyclic voltammetry illustrated that electrostimulation promoted electrochemical activity for redox reactions. Moreover, bacterial community structure analyses indicated electrical stimulation facilitated the enrichment of electroactive and dechlorinating populations on cathode. Metagenomic and quantitative polymerase chain reaction (qPCR) analyses revealed that direct electron transfer (via electrically conductive pili, multi-heme c-type cytochromes) between Axonexus and Desulfovibrio/cathode and indirect electron transfer (via riboflavin) for Dehalococcoides enhanced dechlorination process in BES. Overall, this study verifies the effectiveness of electrostimulated bio-dechlorination and provides novel insights into the mechanisms of dechlorination process enhancement in bioelectrochemical systems through electron transfer networks.


Subject(s)
Electrons , Trichloroethylene , Oxidation-Reduction , Electricity , Electrodes , Trichloroethylene/chemistry , Biodegradation, Environmental
7.
Cutis ; 111(5): E21-E29, 2023 May.
Article in English | MEDLINE | ID: mdl-37406323

ABSTRACT

Spin is a way of reporting that distorts the true findings; we sought to investigate the prevalence of spin in systematic review abstracts on psoriasis treatments and whether study characteristics were associated with spin. We searched MEDLINE and Embase to obtain our sample. Screening and data extraction were performed in a masked duplicate fashion. Each included study was evaluated for the 9 most severe types of spin and other study characteristics. The methodological quality was assessed to explore potential relationships between spin and study quality. Search queries returned 3200 articles, which included 173 systematic reviews. Spin was present in systematic review abstracts. Preventing spin is essential for improving future systematic reviews.

8.
Adv Mater ; 35(36): e2301310, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37196181

ABSTRACT

The sluggish kinetics of oxygen reduction reaction (ORR) and unsatisfactory durability of Pt-based catalysts are severely hindering the commercialization of proton-exchange-membrane fuel cells (PEMFCs). In this work, the lattice compressive strain of Pt-skins imposed by Pt-based intermetallic cores is tailored for highly effective ORR through the confinement effect of the activated nitrogen-doped porous carbon (a-NPC). The modulated pores of a-NPC not only promote Pt-based intermetallics with ultrasmall size (average size of <4 nm), but also efficiently stabilizes intermetallic nanoparticles and sufficient exposure of active sites during the ORR process. The optimized catalyst (L12 -Pt3 Co@ML-Pt/NPC10 ) achieves excellent mass activity (1.72 A mgPt -1 ) and specific activity (3.49 mA cmPt -2 ), which are 11- and 15-fold that of commercial Pt/C, respectively. Besides, owing to the confinement effect of a-NPC and protection of Pt-skins, L12 -Pt3 Co@ML-Pt/NPC10 retains 98.1% mass activity after 30 000 cycles, and even 95% for 100 000 cycles, while Pt/C retains only 51.2% for 30 000 cycles. Rationalized by density functional theory, compared with other metals (Cr, Mn, Fe, and Zn), L12 -Pt3 Co closer to the top of "volcano" induces a more suitable compressive strain and electronic structure on Pt-skin, leading to an optimal oxygen adsorption energy and a remarkable ORR performance.

9.
Small ; 19(25): e2300621, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36932934

ABSTRACT

Tuning the d-orbital electronic configuration of active sites to achieve well-optimized adsorption strength of oxygen-containing intermediates toward reversible oxygen electrocatalysis is desirable for efficient rechargeable Zn-Air batteries but extremely challenging. Herein, this work proposes to construct a Co@Co3 O4 core-shell structure to regulate the d-orbital electronic configuration of Co3 O4 for the enhanced bifunctional oxygen electrocatalysis. Theoretical calculations first evidence that electron donation from Co core to Co3 O4 shell could downshift the d-band center and simultaneously weak spin state of Co3 O4 , result in the well-optimized adsorption strength of oxygen-containing intermediates on Co3 O4 , thus contributing a favor way for oxygen reduction/evolution reaction (ORR/OER) bifunctional catalysis. As a proof-of-concept, the Co@Co3 O4 embedded in Co, N co-doped porous carbon derived from thickness controlled 2D metal-organic-framework is designed to realize the structure of computational prediction and further improve the performance. The optimized 15Co@Co3 O4 /PNC catalyst exhibits the superior bifunctional oxygen electrocatalytic activity with a small potential gap of 0.69 V and a peak power density of 158.5 mW cm-2 in ZABs. Moreover, DFT calculations shows that the more oxygen vacancies on Co3 O4 contribute too strong adsorption of oxygen intermediates which limit the bifunctional electrocatalysis, while electron donation in the core-shell structure can alleviate the negative effect and maintain superior bifunctional overpotential.

10.
Appl Opt ; 62(4): 979-988, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36821156

ABSTRACT

For the X-cube prism three-charge-coupled-device (3CCD) camera, the spectra of the designed dichroic films in the X-cube prism shift with changes in the angle of incident light, producing non-uniformity of color on the image plane. We considered the influence of the incident angle on color performance in filter design and directly optimized the thin film to improve color consistency. An optical model was constructed to calculate the distribution of camera spectral sensitivity and independently correct the non-uniform color on the image plane. Results showed that the optimization and correction methods could significantly improve the color performance of the X-cube prism 3CCD camera.

11.
PLoS One ; 17(9): e0274744, 2022.
Article in English | MEDLINE | ID: mdl-36162079

ABSTRACT

BACKGROUND: Spin-the misrepresentation of a study's actual results-has the potential to alter a clinician's interpretation of the study's findings and therefore could affect patient care. Studies have shown spin frequently occurs in abstracts of systematic reviews from a variety of other medical disorders and specialties. AIMS: Our primary aim was to evaluate whether the nine most severe types of spin occurred in systematic review abstracts' concerning diabetic neuropathy treatments. Secondly, we aimed to determine whether spin presence was associated with the methodological quality of a systematic review. METHODS: A search of MEDLINE and Embase collected 1297 articles focused on diabetic neuropathy treatments, of which we included 114 systematic reviews for spin assessment. Each included study was evaluated for the nine most severe types of spin as defined by Yachitz et al. The methodological quality of a systematic review was determined by using the AMSTAR-2 instrument. All screening and data extraction were conducted in a masked, duplicate fashion. Since the final sample size of 114 was not sufficiently powered to do multivariable logistic regression, we calculated unadjusted odds ratios which evaluated relationships between spin presence within abstracts and study characteristics. RESULTS: From the 114 articles reviewed, spin was present in 7.9% of the studies (9/114), with spin type 5: "conclusion claims the beneficial effect of the experimental treatment despite the high risk of bias in the included primary studies" as the most frequent in our study. Spin types 1, 2, 6, and 8 were not identified. No association was observed between the study characteristics and spin presence, including the methodological quality of a systematic review. CONCLUSIONS: Overall, spin is infrequently observed in abstracts of systematic reviews covering diabetic neuropathy treatments. When comparing our results to other fields of medicine, the field of diabetic neuropathy research publishes systematic reviews whose abstracts mostly portray the findings of the review's full-text to reflect the results adequately.


Subject(s)
Diabetes Mellitus , Diabetic Neuropathies , Cross-Sectional Studies , Diabetic Neuropathies/therapy , Humans , MEDLINE , Research Report , Systematic Reviews as Topic
12.
Eur J Anaesthesiol ; : 701-710, 2022 Jul 06.
Article in English | MEDLINE | ID: mdl-35796313

ABSTRACT

INTRODUCTION: Spin - the beautification of study results to emphasise benefits or minimise harms - is a deceptive reporting strategy with the potential to affect clinical decision-making adversely. Few studies have investigated the extent of spin in systematic reviews. Here, we sought to address this gap by evaluating the presence of the nine most severe forms of spin in the abstracts of systematic reviews on treatments for postoperative nausea and vomiting (PONV). PONV has the potential to increase hospital costs and patient burden, adversely affecting outcomes. METHODS: We developed search strategies for MEDLINE and Embase to identify systematic reviews focused on PONV. Following title and abstract screening of the reviews identified during the initial search, those that met inclusion criteria were evaluated for the presence of spin and received a revised AMSTAR-2 (A Measurement Tool to Assess Systematic Reviews) appraisal by two investigators in a masked, duplicate manner. Study characteristics for each review were also extracted in duplicate. RESULTS: Our systematic search returned 3513 studies, of which 130 systematic reviews and meta-analyses were eligible for data extraction. We found that 29.2% of included systematic reviews contained spin (38/130). Eight of the nine types of spin were identified, with spin type 3 ('selective reporting of or overemphasis on efficacy outcomes or analysis favouring the beneficial effect of the experimental intervention') being the most common. Associations were found between spin and funding source. Spin was more likely in the abstracts of privately funded than nonfunded studies, odds ratio (OR) 2.81 [95% confidence interval (CI), 0.66 to 11.98]. In the abstracts of studies not mentioning funding spin was also more likely than in nonfunded studies, OR 2.30 (95% CI, 0.61 to 8.70). Neither of these results were statistically significant. Significance was found in the association between the presence of spin and AMSTAR-2 ratings: 'low' quality studies were less likely to contain spin than 'high' quality, OR 0.24 (95% CI, 0.07 to 0.88): 'critically low' studies were also less likely to contain spin than 'high' quality studies, OR 0.21 (95% CI, 0.07 to 0.65). There were no other associations between spin and the remaining extracted study characteristics or AMSTAR-2 ratings. CONCLUSION: Spin was present in greater than 29% of abstracts of systematic reviews and meta-analyses regarding PONV. Various stakeholders must take steps to improve the reporting quality of abstracts on PONV.

13.
J Cancer Policy ; 27: 100268, 2021 03.
Article in English | MEDLINE | ID: mdl-35559938

ABSTRACT

BACKGROUND: While spin - i.e., a reporting practice that embellishes positive findings and understates negative ones - is prevalent in randomized controlled trials, it has yet to be investigated in the context of systematic reviews. Owing to their significant role in clinical decision making and patient outcomes, this study seeks to identify and evaluate the severity of spin in the abstracts of systematic reviews on breast cancer. METHODS: We searched MEDLINE and Embase for systematic reviews and meta-analyses focused on breast cancer treatment, screening, and post-treatment quality of life between 1987 and 2020. Investigators independently screened for study selection, extracted spin data, and appraised the methodological quality of reviews using AMSTAR 2. In this cross-sectional study, 11,717 articles were identified, of which 581 met inclusion criteria. Following randomization, the first 200 were evaluated and 21 % contained evidence of at least one of nine types of spin. RESULTS: We identified spin types one, three, four, five, and six but not two, seven, eight, or nine. In particular, pharmacological (AOR 4.36, 95 % CI [1.18-16.01]) and surgical (AOR, 10.10 95 % CI [1.60-63.68]) intervention-type studies were highly associated with spin. There were no other associations between study characteristics and spin. While these results are significant, they contain a wide confidence interval and the reader should draw conclusions accordingly. CONCLUSIONS: There is evidence of spin in meta-analyses and systematic reviews regarding breast cancer treatment and quality of life outcomes. Accordingly, readers of systematic review abstracts related to breast cancer could be misled by distorted presentation of findings. POLICY SUMMARY: This study aims to improve the standards of reporting in systematic reviews and meta-analyses related to cancer.


Subject(s)
Breast Neoplasms , Quality of Life , Breast Neoplasms/diagnosis , Cross-Sectional Studies , Early Detection of Cancer , Female , Humans , Meta-Analysis as Topic , Systematic Reviews as Topic
14.
Foot Ankle Orthop ; 6(1): 24730114211000637, 2021 Jan.
Article in English | MEDLINE | ID: mdl-35097436

ABSTRACT

BACKGROUND: Approximately 18 in every 100 000 people have experienced a ruptured Achilles tendon. Despite the prevalence of this condition, treatment options remain contested. HYPOTHESIS/PURPOSE: The objective of this study was to evaluate the use of spin-reporting practices that may exaggerate benefit or minimize harm-in abstracts of systematic reviews related to Achilles tendon repair. We also evaluated whether particular study characteristics were associated with spin. STUDY DESIGN: Cross-sectional. METHODS: We developed a search strategy for Ovid MEDLINE and Ovid Embase for systematic reviews focused on Achilles tendon treatment. Following title and abstract screening of these search returns, these reviews were evaluated for spin (according to a previously developed classification scheme) and received AMSTAR-2 (A Measurement Tool to Assess Systematic Reviews-2) appraisals by 2 investigators in a masked, duplicate manner. Study characteristics for each review were also extracted in duplicate. RESULTS: Our systematic search returned 251 articles of which 43 systematic reviews and meta-analyses were eligible for data extraction. We found that 65.1% of included studies contained spin (28/43). Spin type 3 was the most common type, occurring in 53.5% (23/43) of abstracts. Spin types 5, 6, 1, and 4 occurred in 16.3% (7/43), 9.3% (4/43), 7% (3/43), and 5.3% (1/43), respectively. Spin types 2, 7, 8, and 9 did not occur. AMSTAR-2 appraised 32.6% (14/43) of the studies as "moderate" quality, 32.6% (14/43) as "low" quality, and 34.9% (15/43) as "critically low" quality. No systematic reviews were rated as "high" quality. There was no significant association between the presence of spin and the following study characteristics: intervention type, article discussing Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) adherence, journal recommending PRISMA adherence, funding sources, journal 5-year impact factor, year the review was received for publication, or AMSTAR-2 critical appraisals. CONCLUSION: Spin was present in abstracts of systematic reviews and meta-analyses-covering Achilles tendon tear treatment. Steps should be taken to improve the reporting quality of abstracts on Achilles tendon treatment as well as other common orthopedic conditions. CLINICAL RELEVANCE: In order to avoid negative patient outcomes, articles should be free of spin within the abstract.

15.
J Colloid Interface Sci ; 581(Pt A): 314-322, 2021 Jan 01.
Article in English | MEDLINE | ID: mdl-32771741

ABSTRACT

Three-dimensional polyaniline (PANI) hydrogel was used as the conductive medium to improve the methane (CH4) production from the anaerobic degradation of organics in wastewater. The porous structure and hydrophilic surface of the PANI hydrogel promoted the adhesion of the anaerobes. The PANI hydrogel existed as a conductive emeraldine base (EB) form with a conductivity of 0.42 S/cm, and had a good biocompatibility with the microorganisms in the anaerobic system. The conductive PANI hydrogel was added into the anaerobic sludge as the conductive medium of the direct interspecies electron transfer (DIET) between bacteria and archaea, accelerating CH4 production during the biodegradation of organic pollutants. The results indicated that the CH4 production rate was increased by 10.50%, 14.21%, 28.77% and 19.30% from the anaerobic system with adding 1000, 2000, 3000 and 4000 mg/L of PANI hydrogel. The proportion of Methanosaeta in the anaerobic sludge with the ability of DIET was increased to 64.74% after adding the PANI hydrogel. The conductive PANI hydrogel served as an electronic channel to enrich the microorganism with the DIET ability, which was responsible for PANI hydrogel improved CH4 production.


Subject(s)
Bioreactors , Water Purification , Anaerobiosis , Aniline Compounds , Hydrogels , Methane
16.
Osteoarthr Cartil Open ; 2(4): 100121, 2020 Dec.
Article in English | MEDLINE | ID: mdl-36474894

ABSTRACT

Objective: Our primary objective was to identify the prevalence of spin - misleading reporting practices that overemphasize benefit or underemphasize harm - within the abstracts of systematic reviews and meta-analyses focused on surgical management of osteoarthritis of the knee. Methods: A search string was developed to search Ovid MEDLINE and Ovid Embase for articles pertaining to surgical management, or quality of life after surgical management, of osteoarthritis of the knee. Titles and abstracts were screened according to our protocol, developed a priori, followed by full-text evaluation for spin in included articles. Study characteristics were simultaneously extracted with spin data and each included study received an AMSTAR-2 quality appraisal. All procedures were performed by two examiners in a masked, duplicate fashion. Results: Of the 1419 articles returned, 96 systematic reviews qualified for inclusion. 35.4% of the included abstracts (34/96) contained at least one type of spin with a total of 36 occurrences (two abstracts contained two types of spin). Selective reporting favoring benefit (type 3; 15/36, 41.7%) was the most prevalent followed by selective reporting of harms (type 6; 7/36, 19.4%). None of the abstracts contained spin types 2, 4, or 8. We found no significant association between spin and either AMSTAR-2 rating or extracted study characteristics. Conclusion: Of the included systematic reviews and meta-analyses, 35.4% contained spin in their abstract. To improve the reliability of systematic reviews and meta-analyses, researchers should act to minimize spin in future abstracts.

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