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OBJECTIVE: Non-suicidal self-injury (NSSI) is an increasingly concerning issue that is linked to a range of mental health problems. However, little is known about the potential neurophysiological mechanisms underlying risk decision-making in Major depressive disorder (MDD) patients with NSSI-the present study aimed to fill this important literature gap. METHODS: A total of 81 MDD patients (with NSSI: n = 40, without NSSI: n = 41) and 44 matched healthy controls (HC) underwent a modified version of the Iowa Gambling Task (IGT) while an electroencephalogram was recorded. Feedback-related negativity (FRN) and P300 were examined during the feedback stage of the risky decision-making process. RESULTS: Behavioural findings revealed that individuals diagnosed with MDD displayed a greater tendency to make risky decisions compared to the control group. Furthermore, MDD patients with NSSI demonstrated a significantly more negative ΔFN (i.e., the difference in neural response to losses compared to gains) than those without NSSI. Further, NSSI patients showed a larger difference ΔFN (loss minus gain), which was associated with enhanced impulsivity. CONCLUSIONS: Collectively, the findings suggest that there is an altered processing of risky decision-making in the electrophysiology of patients with MDD who engage in NSSI. The ΔFN may serve as a psychophysiological marker indicating risk for NSSI.
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The aim of this study was to investigate the global epidemiological trends in the incidence and deaths of acute respiratory infections (ARIs), encompassing both upper respiratory infections (URIs) and lower respiratory infections (LRIs), from 1990 to 2021. Using data from the Global Burden of Disease study 2021 (GBD 2021), we utilized the average annual percentage change (AAPC) to examine the trends in the age-standardized incidence rate and deaths rate (ASIR and ASDRs) of URIs and LRIs. In 2021, the global ASIR of URIs and LRIs were 166,770.73 (95 % UI: 148,098.16-189,487.93) per 100,000 and 4283.61 (95 % UI: 4057.03-4524.89) per 100,000, respectively. The highest ASIR of URIs occurred in high-sociodemographic index (SDI) regions (232744.64, 95 % UI: 206887.07-261694.81) per 100,000, whereas LRIs occurred in low-SDI regions (9261.1, 95 % UI: 8741.61-9820.86) per 100,000. In 2021, the global ASDRs of URIs and LRIs were 0.28 (95 % UI: 0.09-0.61) per 100,000 and 28.67 (95 % UI: 25.92-31.07) per 100,000, respectively. The highest ASDRs of both URIs and LRIs were observed in low-SDI regions, with 1.1 (95 % UI: 0.08-2.78) per 100,000 and 70.68 (95 % UI: 62.56-78.62) per 100,000, respectively. From 1990 to 2021, the global ASIR for URIs and LRIs decreased, with AAPCs of -0.17 % (95 % CI: 0.17 % to -0.16 %) and -1.28 % (95 % CI: -1.37 % to -1.22 %), respectively. The global ASDRs also decreased (-3.39 % for URIs; -2.46 % for LRIs). However, during the COVID-19 pandemic, the ASIR of URIs increased in many countries, especially in high-SDI regions (rate difference before and during the COVID-19 pandemic in ASIR was 2210.19 per 100,000.) and low-SDI regions (rate difference in ASIR: 111.26 per 100,000). The global incidence and deaths related to ARIs have decreased over the past 32 years. However, it remains a significant public health concern, particularly due to the notable incidence of URIs in high SDI regions and the deaths associated with both URIs and LRIs in low SDI regions. Furthermore, an increase in the incidence of URIs was observed in both high- and low-SDI regions during the COVID-19 pandemic, highlighting the need for increased attention.
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Spiking Neural Networks (SNNs), renowned for their low power consumption, brain-inspired architecture, and spatio-temporal representation capabilities, have garnered considerable attention in recent years. Similar to Artificial Neural Networks (ANNs), high-quality benchmark datasets are of great importance to the advances of SNNs. However, our analysis indicates that many prevalent neuromorphic datasets lack strong temporal correlation, preventing SNNs from fully exploiting their spatio-temporal representation capabilities. Meanwhile, the integration of event and frame modalities offers more comprehensive visual spatio-temporal information. Yet, the SNN-based cross-modality fusion remains underexplored. In this work, we present a neuromorphic dataset called DVS-SLR that can better exploit the inherent spatio-temporal properties of SNNs. Compared to existing datasets, it offers advantages in terms of higher temporal correlation, larger scale, and more varied scenarios. In addition, our neuromorphic dataset contains corresponding frame data, which can be used for developing SNN-based fusion methods. By virtue of the dual-modal feature of the dataset, we propose a Cross-Modality Attention (CMA) based fusion method. The CMA model efficiently utilizes the unique advantages of each modality, allowing for SNNs to learn both temporal and spatial attention scores from the spatio-temporal features of event and frame modalities, subsequently allocating these scores across modalities to enhance their synergy. Experimental results demonstrate that our method not only improves recognition accuracy but also ensures robustness across diverse scenarios.
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Tumor proliferation and metastasis are intricately linked to blood vessel formation, with vascular endothelial growth factor (VEGF) playing a pivotal role in orchestrating angiogenesis throughout tumor progression. Pseudolaric acid B (PAB) has emerged as a potent inhibitor of tumor cell proliferation, migration, and angiogenesis. In efforts to enhance its efficacy, 37 derivatives of PAB were synthesized and assessed for their capacity to suppress VEGF secretion in SiHa cells under hypoxic conditions. Notably, majority of these derivatives exhibited significant inhibition of VEGF protein secretion without inducing cytotoxicity. Among them, compound M2 displayed the most potent inhibitory activity, with an IC50 value of 0.68 µM, outperforming the lead compound PAB (IC50 = 5.44 µM). Compound M2 not only curbed the migration and angiogenesis of HUVECs under hypoxic conditions but also hindered the invasion of SiHa cells. Mechanistic investigations unveiled that compound M2 may impede the accumulation and nuclear translocation of hypoxia-inducible factor 1α (HIF-1α) in SiHa cells, thereby downregulating VEGF expression. This inhibitory effect on HIF-1α was corroborated by experiments utilizing the protease inhibitor MG-132 and protein synthesis inhibitor CHX, indicating that compound M2 diminishes HIF-1α levels by reducing its synthesis. Furthermore, compound M2 was observed to modulate the PI3K/AKT/mTOR and MAPK signaling pathways in tumor cells, thereby regulating HIF-1α translation and synthesis. In vivo studies demonstrated that compound M2 exhibited low toxicity and effectively curbed tumor growth. Immunohistochemistry analyses validated that compound M2 effectively suppressed the expression of HIF-1α and VEGF in tumor tissues, underscoring its potential as a promising therapeutic agent for targeting tumor angiogenesis.
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Inibidores da Angiogênese , Antineoplásicos , Proliferação de Células , Diterpenos , Desenho de Fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Fator A de Crescimento do Endotélio Vascular , Humanos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/síntese química , Inibidores da Angiogênese/química , Proliferação de Células/efeitos dos fármacos , Relação Estrutura-Atividade , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Diterpenos/farmacologia , Diterpenos/síntese química , Diterpenos/química , Transdução de Sinais/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Estrutura Molecular , Relação Dose-Resposta a Droga , Linhagem Celular Tumoral , Animais , Movimento Celular/efeitos dos fármacos , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismoRESUMO
Cell-free DNA (cfDNA) analysis has shown potential in detecting early-stage lung cancer based on non-genetic features. To distinguish patients with lung cancer from healthy individuals, peripheral blood were collected from 926 lung cancer patients and 611 healthy individuals followed by cfDNA extraction. Low-pass whole genome sequencing and targeted methylation sequencing were conducted and various features of cfDNA were evaluated. With our customized algorithm using the most optimal features, the ensemble stacked model was constructed, called ESim-seq (Early Screening tech with Integrated Model). In the independent validation cohort, the ESim-seq model achieved an area under the curve (AUC) of 0.948 (95 % CI: 0.915-0.981), with a sensitivity of 79.3 % (95 % CI: 71.5-87.0 %) across all stages at a specificity of 96.0 % (95 % CI: 90.6-100.0 %). Specifically, the sensitivity of the ESim-seq model was 76.5 % (95 % CI: 67.3-85.8 %) in stage I patients, 100 % (95 % CI: 100.0-100.0 %) in stage II patients, 100 % (95 % CI: 100.0-100.0 %) in stage III patients and 87.5 % (95 % CI: 64.6%-100.0 %) in stage IV patients in the independent validation cohort. Besides, we constructed LCSC model (Lung Cancer Subtype multiple Classification), which was able to accurately distinguish patients with small cell lung cancer from those with non-small cell lung cancer, achieving an AUC of 0.961 (95 % CI: 0.949-0.957). The present study has established a framework for assessing cfDNA features and demonstrated the benefits of integrating multiple features for early detection of lung cancer.
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Objectives: Several countries have successfully eliminated measles, and China is making significant strides toward achieving this goal. This study focused on investigating the patterns of measles infections in Zhejiang Province, China, as well as control measures. The objective was to provide valuable insights that could contribute to the development of nationwide elimination strategies. Methods: We analyzed measles surveillance data from 2005 to 2022 in Zhejiang Province. We utilized a joinpoint regression model to examine trends in measles. Additionally, we employed SaTScan software (version 9.5) to identify spatial-temporal clusters. Finally, we used an age-period-cohort model to assess the effects of age, period, and cohort. Results: The age-standardized incidence rate (ASIR) of measles infection in Zhejiang Province from 2005 to 2022 was 5.24 per 100,000, showing a consistent and significant downward trend with an annual percentage change of -24.93% (p<0.05). After 2020, the ASIR for measles infection fell to below 0.1 per 100,000. The majority of measles cases occurred in individuals either without an immunization history or with an unknown immunization status, representing 41.06% and 41.40% of the cases from 2010 to 2022, respectively. According to data from the National Measles Surveillance System, the annual rate of discarded measles cases from 2009 to 2014, and the annual rate of discarded measles and rubella cases from 2015 to 2022, were both above 2 per 100,000, indicating the high sensitivity of the measles surveillance system. Conclusion: The significant reduction in measles incidence from 2005 to 2022 demonstrates substantial progress in Zhejiang Province towards the elimination of measles.
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BACKGROUND: Studies have shown that a history of suicide attempts is associated with low levels of antioxidant vitamins. However, the specific relationship between vitamin C and suicidal ideation remains poorly understood. The purpose of this study is to investigate the effect of vitamin C on the development of suicidal ideation and to explore further the causal relationship using Mendelian randomization (MR). METHODS: Using the 2005-2018 National Health and Nutrition Examination Survey (NHANES) dataset, a comprehensive, cross-sectional, stratified survey of 28,623 participants aged 20 years and older was conducted. Suicidal ideation was assessed using item 9 of the Patient Health Questionnaire-9 (PHQ-9) item. The relationship between vitamin C and suicidal ideation was revealed by weighted multiple linear regression, smooth curve fitting, hierarchical analysis, and interaction test. To determine causality, MR was performed on vitamin C and suicidal ideation. RESULTS: In cross-sectional studies, all models showed a negative association between vitamin C and suicidal ideation, with a 37 % reduction in the risk of suicidal ideation for each unit increase in vitamin C in the highest quartile in the fully adjusted model. The results of the subgroup analysis showed that the association between vitamin C and suicidal ideation was stable across gender, age, education, smoking status, and marital status. In the MR study, our bivariate model showed no significant causal relationship between vitamin C and the development of suicidal ideation. CONCLUSIONS: Dietary vitamin C intake was negatively associated with the development of suicidal ideation. However, genetic evidence does not support causation of these associations.
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Weakly supervised group activity recognition (WSGAR) aims at identifying the overall behavior of multiple persons without any fine-grained supervision information (including individual position and action label). Traditional methods usually adopt a person-to-whole way: detect persons via off-the-shelf detectors, obtain person-level features, and integrate into the group-level features for training the classifier. However, these methods are unflexible due to serious reliance on the quality of detectors. To get rid of the detector, recent works learn several prototype tokens from noisy grid features with learnable weights directly, which treat all the local visual information equally and bring in redundant and ambiguous information to some extent. To this end, we propose a novel coarse-fine nested network (CFNN) to coarsely localize the key visual patches of activity and further finely learn the local features, as well as the global features. Specifically, we design a nested interactor (NI) to progressively model the spatiotemporal interactions of the learnable global token. According to the cue of spatial interaction in NI, we localize several key visual patches via a new coarse-grained spatial localizer (CSL). Then, we finally encode these localized visual patches with the help of global spatiotemporal dependency via a new fine-grained spatiotemporal selector (FSS). Extensive experiments on Volleyball and NBA datasets demonstrate the effectiveness of the proposed CFNN compared with the existing competitive methods. Code is available at: https://github.com/gexiaojingshelby/CFNN.
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The popularity of online shopping in China has increased significantly, creating new development opportunities for the express delivery industry. However, the rapid expansion of the express industry has also created challenges in the parcel sorting process. The demanding nature of parcel sorting work, which is characterized by intense and prolonged repetitive tasks, makes individuals particularly vulnerable to the effects of fatigue. Fatigue is a complex condition that encompasses both physiological and psychological exhaustion. It often results in reduced energy levels and diminished functionality, significantly impacting an individual's performance at work and their overall well-being. This study aimed to investigate how physiological and psychological fatigue affects sorting efficiency and to identify appropriate rest periods that will allow employees to maintain their performance levels. The research involved fifteen participants who took part in a 60 min continuous sorting experiment and a similar experiment with scheduled breaks. During both trials, we collected data on participants' electromyography (EMG) and electrodermal activity (EDA), as well as subjective fatigue ratings (RPE). Signal features such as the median frequency (MF) of EMG and the skin conductance level (SCL) were analyzed to assess physiological and psychological fatigue, respectively. The results show that physiological fatigue mainly affects sorting efficiency in the first 30 min, while psychological fatigue becomes more influential in the following half-hour period. In addition, subjective fatigue levels during the first 30 min are primarily determined by psychological factors, while beyond that point, both physiological and psychological fatigue contribute to subjective fatigue. Rest periods of 415-460 s, based on EDA recovery times, effectively support sorting efficiency and participants' recovery. This study highlights the complex ways in which fatigue affects parcel sorting performance and provides valuable theoretical and practical insights for establishing labor quotas and optimizing work schedules in the parcel sorting industry.
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Fadiga , Fadiga Mental , Humanos , Masculino , Adulto , Fadiga/fisiopatologia , Fadiga/psicologia , Feminino , Fadiga Mental/fisiopatologia , Eletromiografia , Adulto Jovem , Resposta Galvânica da Pele/fisiologia , Eficiência/fisiologia , Desempenho ProfissionalRESUMO
Image stitching is a traditional but challenging computer vision task. The goal is to stitch together multiple images with overlapping areas into a single, natural-looking, high-resolution image without ghosts or seams. This article aims to increase the field of view of gastroenteroscopy and reduce the missed detection rate. To this end, an improved depth framework based on unsupervised panoramic image stitching of the gastrointestinal tract is proposed. In addition, preprocessing for aberration correction of monocular endoscope images is introduced, and a C2f module is added to the image reconstruction network to improve the network's ability to extract features. A comprehensive real image data set, GASE-Dataset, is proposed to establish an evaluation benchmark and training learning framework for unsupervised deep gastrointestinal image splicing. Experimental results show that the MSE, RMSE, PSNR, SSIM and RMSE_SW indicators are improved, while the splicing time remains within an acceptable range. Compared with traditional image stitching methods, the performance of this method is enhanced. In addition, improvements are proposed to address the problems of lack of annotated data, insufficient generalization ability and insufficient comprehensive performance in image stitching schemes based on supervised learning. These improvements provide valuable aids in gastrointestinal examination.
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Algoritmos , Processamento de Imagem Assistida por Computador , Humanos , Processamento de Imagem Assistida por Computador/métodos , Trato Gastrointestinal/diagnóstico por imagem , Aprendizado Profundo , Aprendizado de Máquina não Supervisionado , Endoscopia Gastrointestinal/métodosRESUMO
Background and Aims: For patients with high-risk non-ST elevation myocardial infarction (NSTEMI), current guidelines recommend an early invasive strategy within 24 h. New-onset acute ischemic stroke (NAIS) is a rare but fatal complication of percutaneous coronary intervention (PCI). However, the effect of the timing of PCI and the risk of NAIS in NSTEMI is poorly defined. Methods: Patients with NSTEMI who underwent PCI were queried from the National Inpatient Sample Database (2016-2019) and stratified into three groups: early (<24 h), medium (24-72 h), and late (>72 h) PCI. Multivariate logistic regression models were used to determine the association between timing of PCI and NAIS. Results: Among 633,115 weighted hospitalizations, patients in the late PCI group had a higher incidence of NAIS (1.3%) than those in the early (0.67%) and medium (0.71%) PCI groups. Patients undergoing late PCI were older, more likely to be female, and had a greater incidence of comorbidities (e.g., diabetes mellitus, chronic pulmonary and renal illness, and atrial fibrillation) than those undergoing early or medium PCI. After adjustment, only late PCI was significantly associated with a 54% increased NAIS risk (adjusted odds ratio: 1.54 [95% confidence interval: 1.29-1.84]). Additionally, there was heterogeneity in the magnitude of risk by age and sex. Younger people (<65 years) (p for interaction <0.001) and men (interaction-value p = 0.040) were more likely to encounter NAIS. Conclusion: Late PCI was associated with a higher risk of NAIS than early PCI, particularly among men and those aged <65 years.
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Purpose: The aim of this work was to investigate and compare back and lower extremity joint moments and muscle excitation during stoop and squat postures by incorporating gender-based differences and analyzing lifting phases. Methods: 18 healthy adults (9 males and 9 females; age: 24.44 ± 4.96 years, body mass: 66.00 ± 12.10 kg, height: 170.11 ± 9.20 cm, lean body mass: 48.46 ± 7.66 kg) lifted an object 30% of their lean body mass using squat and stoop postures. Marker-based motion capture, force plate, and surface electromyography were synchronously used to acquire joint moments and muscle excitation. A 3-way mixed model analysis was performed to determine the effect of gender, posture, and phase on internal joint moments and muscle excitation of the lower back and extremities. Results: Significant differences were observed in the interaction of lifting posture and phase on lower extremity moments and excitation of rectus femoris and medial gastrocnemius. Individual effects of posture were significant for peak internal joint moments of the lower extremities only. Anterior lower extremity muscles showed significantly increased excitation during squat, whereas medial gastrocnemius was higher in stoop. Joint moments and muscle excitations were all higher during the lifting than the bending phase. Gender differences were found only in the peak lumbosacral sagittal plane moment and rectus femoris muscle excitation. Conclusions: The study identified significant variations in the joint moments and muscle excitation in lifting, influenced by gender, posture, and phase, highlighting its complex nature. Overall interactions were lacking, however individual effects were evident, necessitating larger future studies.
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Remoção , Extremidade Inferior , Músculo Esquelético , Postura , Humanos , Feminino , Masculino , Postura/fisiologia , Extremidade Inferior/fisiologia , Estudos Transversais , Adulto Jovem , Adulto , Músculo Esquelético/fisiologia , Caracteres Sexuais , Dorso/fisiologia , Eletromiografia , Fenômenos BiomecânicosRESUMO
A zinc-organic hybrid (1) with multifunctional room temperature phosphorescence (RTP) was synthesized. 1 presents light/force-sensitive RTP properties due to the photochromic behavior from gray to light yellow and the transition from crystalline to amorphous state, respectively. Furthermore, inkless printing and information encryption models were successfully constructed to prove their widespread application prospect.
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OBJECTIVE: To identify the spatial-temporal pattern variation of whole-brain functional connectivity (FC) during reward processing in melancholic major depressive disorder (MDD) patients, and to determine the clinical correlates of connectomic differences. METHODS: 61 MDD patients and 32 healthy controls were enrolled into the study. During magnetoencephalography (MEG) scanning, all participants completed the facial emotion recognition task. The MDD patients were further divided into two groups: melancholic (n = 31) and non-melancholic (n = 30), based on the Mini International Neuropsychiatric Interview (M.I.N.I.) assessment. Melancholic symptoms were examined by using the 6-item melancholia subscale from the Hamilton Depression Rating Scale (HAM-D6). The whole-brain orthogonalized power envelope connections in the high-beta band (20-35 Hz) were constructed in each period after the happy emotional stimuli (0-200 ms, 100-300 ms, 200-400 ms, 300-500 ms, and 400-600 ms). Then, the network-based statistic (NBS) was used to determine the specific abnormal connection patterns in melancholic MDD patients. RESULTS: The NBS identified a sub-network difference at the mid-late period (300-500 ms) in response to happy faces among the three groups (corrected P = 0.035). Then, the post hoc and correlation analyses found five FCs were decreased in melancholic MDD patients and were related to HAM-D6 score, including FCs of left fusiform gyrus-right orbital inferior frontal gyrus (r = -0.52, P < 0.001), left fusiform gyrus-left amygdala (r = -0.26, P = 0.049), left posterior cingulate gyrus-right precuneus (r = -0.32, P = 0.025), left precuneus-right precuneus (r = -0.27, P = 0.049), and left precuneus-left inferior occipital gyrus (r = -0.32, P = 0.025). CONCLUSION: In response to happy faces, melancholic MDD patients demonstrated a disrupted functional connective pattern (20-35 Hz, 300-500 ms), which involved brain regions in visual information processing and the limbic system. The aberrant functional connective pattern in reward processing might be a biomarker of melancholic MDD.
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Transtorno Depressivo Maior , Magnetoencefalografia , Recompensa , Humanos , Feminino , Masculino , Transtorno Depressivo Maior/fisiopatologia , Transtorno Depressivo Maior/diagnóstico por imagem , Adulto , Pessoa de Meia-Idade , Reconhecimento Facial/fisiologia , Encéfalo/fisiopatologia , Encéfalo/diagnóstico por imagem , Ritmo beta/fisiologia , Conectoma/métodos , Rede Nervosa/fisiopatologia , Rede Nervosa/diagnóstico por imagem , Adulto Jovem , Expressão Facial , Emoções/fisiologiaRESUMO
An improved understanding of the factors associated with suicidal attempts in youth suffering from depression is crucial for the identification and prevention of future suicide risk. However, there is limited understanding of how neural activity is modified during the process of decision-making. Our study aimed to investigate the neural responses in suicide attempters with major depressive disorder (MDD) during decision-making. Electroencephalography (EEG) was recorded from 79 individuals aged 16-25 with MDD, including 39 with past suicide attempts (SA group) and 40 without (NSA group), as well as from 40 age- and sex- matched healthy controls (HCs) during the Iowa Gambling Task (IGT). All participants completed diagnostic interviews, self-report questionnaires. Our study examined feedback processing by measuring the feedback-related negativity (FRN), ΔFN (FRN-loss minus FRN-gain), and the P300 as electrophysiological indicators of feedback evaluation. The SA group showed poorest IGT performance. SA group and NSA group, compared with HC group, exhibited specific deficits in decision-making (i.e., exhibited smaller (i.e., blunted) ΔFN). Post hoc analysis found that the SA group was the least sensitive to gains and the most sensitive to losses. In addition, we also found that the larger the value of ΔFN, the better the decision-making ability and the lower the impulsivity. Our study highlights the link between suicide attempts and impaired decision-making in individuals with major depressive disorder. These findings constitute an important step in gaining a better understanding of the specific reward-related abnormalities that could contribute to the young MDD patients with suicide attempts.
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Tomada de Decisões , Transtorno Depressivo Maior , Eletroencefalografia , Tentativa de Suicídio , Humanos , Transtorno Depressivo Maior/fisiopatologia , Transtorno Depressivo Maior/psicologia , Masculino , Feminino , Adolescente , Tentativa de Suicídio/psicologia , Tomada de Decisões/fisiologia , Adulto Jovem , Adulto , Potenciais Evocados/fisiologia , Encéfalo/fisiopatologiaRESUMO
Eukaryotic chromosome segregation requires kinetochores, multi-megadalton protein machines that assemble on the centromeres of chromosomes and mediate attachments to dynamic spindle microtubules. Kinetochores are built from numerous complexes, and there has been progress in structural studies on recombinant subassemblies. However, there is limited structural information on native kinetochore architecture. To address this, we purified functional, native kinetochores from the thermophilic yeast Kluyveromyces marxianus and examined them by electron microscopy (EM), cryoelectron tomography (cryo-ET), and atomic force microscopy (AFM). The kinetochores are extremely large, flexible assemblies that exhibit features consistent with prior models. We assigned kinetochore polarity by visualizing their interactions with microtubules and locating the microtubule binder, Ndc80c. This work shows that isolated kinetochores are more dynamic and complex than what might be anticipated based on the known structures of recombinant subassemblies and provides the foundation to study the global architecture and functions of kinetochores at a structural level.
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Cinetocoros , Kluyveromyces , Kluyveromyces/citologia , Cinetocoros/química , Cinetocoros/metabolismo , Cinetocoros/ultraestrutura , Proteínas Associadas aos Microtúbulos/análise , Proteínas Fúngicas/análise , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Microtúbulos/metabolismo , Tomografia com Microscopia EletrônicaRESUMO
[This corrects the article DOI: 10.1016/j.ekir.2024.02.771.].
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The improvement of hydrogen evolution reaction kinetics can be largely accelerated by introducing a well-designed hydrogen spillover pathway into the catalysts. However, the driving force and mechanism of hydrogen migration on the surface of catalysts are poorly understood and are rarely explored in depth. Here, inspired by the specific ferroelectric property of HfO2, Mn-O-Ca sites in Mn4CaO5, and Fe-Fe sites in hydrogenases, we constructed a bioinspired HfO2 coupled with Ir catalysts (Ir/HfO2@C) with an alkaline hydrogen reverse spillover effect from HfO2 to interface and acid hydrogen spillover effect from Ir to interface. Benefiting from the bidirectional hydrogen spillover pathways controlled by pH, Ir/HfO2@C displays a narrow overpotential difference between acidic and alkaline electrolytes. Remarkably, Ir/HfO2@C shows a remarkable mass current density and turnover frequency value, far exceeding the benchmark Ir/C by 20.6 times. More importantly, this Ir/HfO2@C achieves extraordinarily low overpotentials of 146 and 39 mV at 10 mV cm-2 in seawater and alkaline seawater, respectively. The anion-exchange membrane water electrolyzer equipped with Ir/HfO2@C as a cathode exhibits excellent and stable H2-evolution performance on 2.22 V at 1.0 A cm-2. We expect that the bioinspired strategy will provide a new concept for designing catalytic materials for efficient and pH-universal electrochemical hydrogen production.
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Sc2CO2 MXene has potential applications in energy storage and optoelectronics due to its superior structure and excellent properties. The electronic properties, quantum capacitance, and photocatalytic activity of Cr-doped Sc2CO2 under strain are studied by the density functional theory. Cr doping makes the system produce magnetism. The spin-down states of Sc2CO2-Cr under strain are direct semiconductors, while their spin-up states are indirect semiconductors. Sc2CO2-Cr under +5, -5, -3, and -2% strains in an aqueous system are suitable for cathode material. A large voltage drastically modulates the type of electrode materials. Sc2CO2-Cr under strains from 0 to +2% can perform the oxygen evolution reaction at an alkaline environment, while the Sc2CO2-Cr system under strain is a good for CO2 photocatalysis at pH 0 and 7.
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BACKGROUND: The widespread problem of suicide and its severe burden in bipolar disorder (BD) necessitate the development of objective risk markers, aiming to enhance individual suicide risk prediction in BD. METHODS: This study recruited 123 BD patients (61 patients with prior suicide attempted history (PSAs), 62 without (NSAs)) and 68 healthy controls (HEs). The Latent Dirichlet Allocation (LDA) model was used to decompose the resting state functional connectivity (RSFC) into multiple hyper/hypo-RSFC patterns. Thereafter, according to the quantitative results of individual heterogeneity over latent factor dimensions, the correlations were analyzed to test prediction ability. RESULTS: Model constructed without introducing suicide-related labels yielded three latent factors with dissociable hyper/hypo-RSFC patterns. In the subsequent analysis, significant differences in the factor distributions of PSAs and NSAs showed biases on the default-mode network (DMN) hyper-RSFC factor (factor 3) and the salience network (SN) and central executive network (CEN) hyper-RSFC factor (factor 1), indicating predictive value. Correlation analysis of the individuals' expressions with their Nurses' Global Assessment of Suicide Risk (NGASR) revealed factor 3 positively correlated (r = 0.4180, p < 0.0001) and factor 1 negatively correlated (r = - 0.2492, p = 0.0055) with suicide risk. Therefore, it could be speculated that patterns more associated with suicide reflected hyper-connectivity in DMN and hypo-connectivity in SN, CEN. CONCLUSIONS: This study provided individual suicide-associated risk factors that could reflect the abnormal RSFC patterns, and explored the suicide related brain mechanisms, which is expected to provide supports for clinical decision-making and timely screening and intervention for individuals at high risks of suicide.