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1.
ACS Nano ; 18(33): 22474-22483, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39110064

RESUMO

High density and high semiconducting-purity single-walled carbon nanotube array (A-CNT) have recently been demonstrated as promising candidates for high-performance nanoelectronics. Knowledge of the structures and arrangement of CNTs within the arrays and their interfaces to neighboring CNTs, metal contacts, and dielectrics, as the key components of an A-CNT field effect transistor (FET), is essential for device mechanistic understanding and further optimization, particularly considering that the current technologies for the fabrication of A-CNT wafers are mainly laboratory-level solution-based processes. Here, we conduct a systematic investigation into the microstructures of A-CNT FETs mainly via cross-sectional high-resolution transmission electron microscopy and tentatively establish a framework consisting of up to 11 parameters which can be used for structure-side quality evaluation of the A-CNT FETs. The parameter ensemble includes the diameter, length (or terminal), and density distribution of CNTs, radial deformation of CNTs, array alignment defects, surface crystallography facets of contact metal, thickness distribution of high-k dielectrics (HfO2), and the contact ratios for the CNT-CNT, CNT-metal, CNT-dielectric, and CNT-substrate interfaces. Enriched array alignment defects, i.e., bundle, stacking, misorientation, and voids, are observed with a total ratio sometimes up to ∼90% in pristine A-CNTs and even up to ∼95% after the device fabrication process. Thus, they are suggested as the prevalent performance-limiting factors for A-CNT FETs. Complex interfacial structures are observed at the CNT-CNT, CNT-metal contact, and CNT-high-k dielectric interfaces, making the local environment and the property of each component CNT involved in an A-CNT FET distinct from others in terms of the diameters, radial deformation, and interactions with the local surroundings (mainly through van der Waals interactions). The present study suggests further improvements on the fabrication technology of A-CNT wafers and devices and mechanistic investigations into the impacts of complex array alignment defects and interface structures on the electrical performance of A-CNT FETs as well.

2.
Eur J Med Res ; 29(1): 373, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39026357

RESUMO

BACKGROUND: Primary cardiac tumors, while rare, present significant clinical challenges due to their diverse pathology and presentation. Lung cancer frequently metastasizes to the heart; however, cases involving primary cardiac tumors of different origins alongside primary lung cancer are exceedingly rare in the literature. CASE PRESENTATION: We report the case of a 53-year-old female who presented with hemoptysis and was subsequently diagnosed with a left atrial myxoma, pulmonary squamous cell carcinoma, and a thymic cyst. This coexistence of multiple non-homologous tumors in a single patient is exceedingly rare. CONCLUSION: This case underscores the complexity of diagnosing and managing patients with multiple distinct tumors. The simultaneous occurrence of a primary cardiac myxoma, pulmonary squamous cell carcinoma, and thymic cyst is unprecedented, providing valuable insights for future clinical practice.


Assuntos
Carcinoma de Células Escamosas , Átrios do Coração , Neoplasias Cardíacas , Neoplasias Pulmonares , Cisto Mediastínico , Mixoma , Humanos , Mixoma/complicações , Mixoma/cirurgia , Mixoma/patologia , Feminino , Pessoa de Meia-Idade , Carcinoma de Células Escamosas/cirurgia , Carcinoma de Células Escamosas/complicações , Carcinoma de Células Escamosas/patologia , Neoplasias Pulmonares/cirurgia , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/patologia , Cisto Mediastínico/cirurgia , Cisto Mediastínico/complicações , Cisto Mediastínico/patologia , Neoplasias Cardíacas/cirurgia , Neoplasias Cardíacas/complicações , Neoplasias Cardíacas/patologia , Átrios do Coração/patologia , Átrios do Coração/cirurgia , Neoplasias Primárias Múltiplas/cirurgia , Neoplasias Primárias Múltiplas/patologia , Neoplasias Primárias Múltiplas/complicações
4.
Langmuir ; 40(29): 15322-15331, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38981013

RESUMO

Bubble transportation and related flotation are ubiquitous phenomena in nature and industry. Various surfaces with distinct morphologies and specific wettability properties have been engineered by organisms in nature and by humans to facilitate the targeted movement of bubbles. However, existing methods predominantly rely on continuous surfaces, limiting the ability of bubbles to deviate from their path before reaching their intended destination. Therefore, directional transportation of bubbles using noncontiguous surfaces still remains a significant challenge. Inspired by water spiders' ability to capture bubbles underwater using their hydrophobic surface for survival, we propose a novel transport strategy that utilizes patterned superhydrophobic surfaces (PSHSs) and a superhydrophobic tweezer. This strategy is implemented by switching between the hood mode and puncture mode of the moving three-phase contact lines to load and unload the bubble. To quantitatively evaluate the loss ratio of the bubble during transportation, a simple and exquisite bubble-weighing apparatus is devised. Our findings indicate that circular PSHSs demonstrate superior bubble adhesion and achieve the highest bubble transport ratio of 95.1%. In order to validate the promising application of this novel method, we employ the computer numerical control (CNC) technology to facilitate the autonomous loading and precise transportation of underwater bubbles, as well as the blending and ionization of combustible gas bubbles with air bubbles at different volume ratios.

5.
Nucleic Acids Res ; 52(14): 8609-8627, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-38967005

RESUMO

High spontaneous mutation rate is crucial for obtaining ideal phenotype and exploring the relationship between genes and phenotype. How to break the genetic stability of organisms and increase the mutation frequency has become a research hotspot. Here, we present a practical and controllable evolutionary tool (oMut-Cgts) based on dual genetic level modification engineering for Corynebacterium glutamicum. Firstly, the modification engineering of transcription and replication levels based on RNA polymerase α subunit and DNA helicase Cgl0854 as the 'dock' of cytidine deaminase (pmCDA1) significantly increased the mutation rate, proving that the localization of pmCDA1 around transient ssDNA is necessary for genome mutation. Then, the combined modification and optimization of engineering at dual genetic level achieved 1.02 × 104-fold increased mutation rate. The genome sequencing revealed that the oMut-Cgts perform uniform and efficient C:G→T:A transitions on a genome-wide scale. Furthermore, oMut-Cgts-mediated rapid evolution of C. glutamicum with stress (acid, oxidative and ethanol) tolerance proved that the tool has powerful functions in multi-dimensional biological engineering (rapid phenotype evolution, gene function mining and protein evolution). The strategies for rapid genome evolution provided in this study are expected to be applicable to a variety of applications in all prokaryotic cells.


Assuntos
Corynebacterium glutamicum , Genoma Bacteriano , Corynebacterium glutamicum/genética , Engenharia Genética/métodos , Citidina Desaminase/genética , Citidina Desaminase/metabolismo , Taxa de Mutação , Evolução Molecular , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , DNA Helicases/genética , DNA Helicases/metabolismo , Replicação do DNA/genética , Mutação
7.
World J Clin Cases ; 12(19): 3936-3941, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38994295

RESUMO

BACKGROUND: Pancreatic cancer presents a challenge with its low early diagnosis and treatment rates, leading to high metastasis and mortality rates. The median survival time for advanced pancreatic cancer is a mere 3 months. However, there's hope: small pancreatic cancers diagnosed at an early stage (T1) or those less than or equal to 1 cm in diameter boast an impressive 5-year survival rate of nearly 100%. This underscores the critical importance of early pancreatic cancer detection for significantly improving prognosis. CASE SUMMARY: Pancreatic cancer, a malignant tumor of the digestive tract, poses challenges in both diagnosis and treatment due to its occult and atypical clinical symptoms. Clinically, patients with recurrent pancreatitis should be vigilant, as it may be indicative of pancreatic cancer, particularly in middle-aged and elderly patients. Here, we presented the case of a patient who experienced recurrent acute pancreatitis within a span of 2 months. During the initial episode of pancreatitis, routine imaging failed to identify the cause of pancreatic cancer. However, upon recurrence of acute pancreatitis, endoscopic ultrasonography (EUS) revealed a space-occupying lesion approximately 1 cm in size in the pancreatic body. Subsequent EUS coupled with fine-needle aspiration examination demonstrated atypical pancreatic gland epithelium. Ultimately, the patient underwent surgery and was diagnosed with an intraductal papillary mucinous tumor of the pancreas (severe epithelial dysplasia, focal cancer). CONCLUSION: We recommend EUS for patients with recurrent pancreatitis of unknown etiology to exclude early pancreatic cancer.

8.
Chem Sci ; 15(27): 10508-10518, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38994413

RESUMO

Hsp90α, a pivotal canonical chaperone, is renowned for its broad interaction with numerous protein clients to maintain protein homeostasis, chromatin remodeling, and cell growth. Recent studies indicate its role in modifying various components of membraneless organelles (MLOs) such as stress granules and processing bodies, suggesting its participation in the regulation of protein condensates. In this study, we found that Hsp90α possesses an inherent ability to form dynamic condensates in vitro. Utilizing LC-MS/MS, we further pinpointed proteins in cell lysates that preferentially integrate into Hsp90α condensates. Significantly, we observed a prevalence of RG motif repeats in client proteins of Hsp90α condensates, many of which are linked to various MLOs. Moreover, each of the three domains of Hsp90α was found to undergo phase separation, with numerous solvent-exposed negatively charged residues on these domains being crucial for driving Hsp90α condensation through multivalent weak electrostatic interactions. Additionally, various clients like TDP-43 and hnRNPA1, along with poly-GR and PR dipeptide repeats, exhibit varied impacts on the dynamic behavior of Hsp90α condensates. Our study spotlights various client proteins associated with Hsp90α condensates, illustrating its intricate adaptive nature in interacting with diverse clients and its functional adaptability across multiple MLOs.

9.
ISME J ; 18(1)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-39018220

RESUMO

Phenotypic plasticity, which involves phenotypic transformation in the absence of genetic change, may serve as a strategy for organisms to survive in complex and highly fluctuating environments. However, its reaction norm, molecular basis, and evolution remain unclear in most organisms, especially microbial eukaryotes. In this study, we explored these questions by investigating the reaction norm, regulation, and evolution of phenotypic plasticity in the cosmopolitan marine free-living ciliates Glauconema spp., which undergo significant phenotypic changes in response to food shortages. This study led to the de novo assembly of macronuclear genomes using long-read sequencing, identified hundreds of differentially expressed genes associated with phenotypic plasticity in different life stages, validated the function of two of these genes, and revealed that the reaction norm of body shape in response to food density follows a power-law distribution. Purifying selection may be the dominant evolutionary force acting on the genes associated with phenotypic plasticity, and the overall data support the hypothesis that phenotypic plasticity is a trait maintained by natural selection. This study provides novel insight into the developmental genetics of phenotypic plasticity in non-model unicellular eukaryotes and sheds light on the complexity and long evolutionary history of this important survival strategy.


Assuntos
Cilióforos , Fenótipo , Cilióforos/genética , Cilióforos/classificação , Seleção Genética , Adaptação Fisiológica/genética , Organismos Aquáticos/genética , Genoma de Protozoário
10.
Biomolecules ; 14(7)2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39062588

RESUMO

Guanylate binding protein 5 (GBP5) is an emerging immune component that has been increasingly recognized for its involvement in autoimmune diseases, particularly inflammatory bowel disease (IBD). IBD is a complex disease involving inflammation of the gastrointestinal tract. Here, we explored the functional significance of GBP5 using Gbp5 knockout mice and wildtype mice exposed to dextran sulfate sodium (DSS) to generate chronic colitis model. We found that Gbp5 deficiency protected mice from DSS-induced chronic colitis. Transcriptome analysis of colon tissues showed reduced immune responses in Gbp5 knockout mice compared to those in corresponding wildtype mice. We further observed that after repeated DSS exposure, the gut microbiota was altered, both in wildtype mice and Gbp5 knockout mice; however, the gut microbiome health index was higher in the Gbp5 knockout mice. Notably, a probiotic murine commensal bacterium, Dubosiella, was predominantly enriched in these knockout mice. Our findings suggest that GBP5 plays an important role in promoting inflammation and dysbiosis in the intestine, the prevention of which might therefore be worth exploring in regards to IBD treatment.


Assuntos
Colite , Sulfato de Dextrana , Modelos Animais de Doenças , Microbioma Gastrointestinal , Camundongos Knockout , Animais , Camundongos , Doença Crônica , Colite/microbiologia , Colite/induzido quimicamente , Colite/imunologia , Colite/genética , Colite/metabolismo , Disbiose/microbiologia , Disbiose/imunologia , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/metabolismo , Proteínas de Ligação ao GTP/deficiência , Camundongos Endogâmicos C57BL
11.
Anal Chim Acta ; 1312: 342778, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38834257

RESUMO

BACKGROUND: The technology of capturing circulating tumor cells (CTCs) plays a crucial role in the diagnosis, evaluation of therapeutic efficacy, and prediction of prognosis in lung cancer. However, the presence of complex blood environment often results in severe nonspecific protein adsorption and interferences from blood cells, which negatively impacts the specificity of CTCs capture. There is a great need for development of novel nanomaterials for CTCs capture with prominent anti-nonspecific adsorptions from proteins or blood cells. RESULTS: We present a novel immune magnetic probe Fe3O4@(PEI/AA)4@Apt. The surface of Fe3O4 particles was modified with four layers of PEI/AA composite by layer-by-layer assembly. Furthermore, aptamers targeting epithelial marker EpCAM (SYL3C) and mesenchymal marker CSV (ZY5C) were simultaneously connected on Fe3O4@(PEI/AA)4 to improve the detection of different phenotypic CTCs and reduce false negatives. The results demonstrated that the (PEI/AA)4 coatings not only minimized non-specific protein adsorptions, but also significantly reduced the adsorption rate of red blood cells to a mere 1 %, as a result of which, the Fe3O4@(PEI/AA)4@Apt probe achieved a remarkably high capture efficiency toward CTCs (95.9 %). In the subsequent validation of clinical samples, the probe was also effective in capturing rare CTCs from lung cancer patients. SIGNIFICANCE AND NOVELTY: A (PEI/AA) polymerized composite with controllable layers was fabricated by layer-by-layer self-assembly technique, which displayed remarkable anti-nonspecific adsorption capabilities toward proteins and cells. Importantly, Fe3O4@(PEI/AA)4@Apt probe significantly improved CTCs capture purity in lung cancer patients to 89.36 %. For the first time, this study combined controllable (PEI/AA) layers with magnetic separation to innovatively build a resistant interface that significantly improves the specific capture performances of CTCs, broadening the application of this polymerized composite.


Assuntos
Alginatos , Células Neoplásicas Circulantes , Polietilenoimina , Humanos , Células Neoplásicas Circulantes/patologia , Polietilenoimina/química , Alginatos/química , Nanopartículas de Magnetita/química , Neoplasias Pulmonares/patologia , Aptâmeros de Nucleotídeos/química , Adsorção , Propriedades de Superfície , Molécula de Adesão da Célula Epitelial/imunologia
12.
IEEE Trans Image Process ; 33: 3935-3949, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38917291

RESUMO

The ability to detect and track the dynamic objects in different scenes is fundamental to real-world applications, e.g., autonomous driving and robot navigation. However, traditional Multi-Object Tracking (MOT) is limited to track objects belonging to the pre-defined closed-set categories. Recently, Generic MOT (GMOT) is proposed to track interested objects beyond pre-defined categories and it can be divided into Open-Vocabulary MOT (OVMOT) and Template-Image-based MOT (TIMOT). Taking the consideration that the expensive well pre-trained (vision-)language model and fine-grained category annotations are required to train OVMOT models, in this paper, we focus on TIMOT and propose a simple but effective method, Siamese-DETR. Only the commonly used detection datasets (e.g., COCO) are required for training. Different from existing TIMOT methods, which train a Single Object Tracking (SOT) based detector to detect interested objects and then apply a data association based MOT tracker to get the trajectories, we leverage the inherent object queries in DETR variants. Specifically: 1) The multi-scale object queries are designed based on the given template image, which are effective for detecting different scales of objects with the same category as the template image; 2) A dynamic matching training strategy is introduced to train Siamese-DETR on commonly used detection datasets, which takes full advantage of provided annotations; 3) The online tracking pipeline is simplified through a tracking-by-query manner by incorporating the tracked boxes in the previous frame as additional query boxes. The complex data association is replaced with the much simpler Non-Maximum Suppression (NMS). Extensive experimental results show that Siamese-DETR surpasses existing MOT methods on GMOT-40 dataset by a large margin.

13.
Emerg Microbes Infect ; 13(1): 2368221, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38932432

RESUMO

A positive-sense (+) single-stranded RNA (ssRNA) virus (e.g. enterovirus A71, EV-A71) depends on viral polypeptide translation for initiation of virus replication after entry. We reported that EV-A71 hijacks Hsp27 to induce hnRNP A1 cytosol redistribution to initiate viral protein translation, but the underlying mechanism is still elusive. Here, we show that phosphorylation-deficient Hsp27-3A (Hsp27S15/78/82A) and Hsp27S78A fail to translocate into the nucleus and induce hnRNP A1 cytosol redistribution, while Hsp27S15A and Hsp27S82A display similar effects to the wild type Hsp27. Furthermore, we demonstrate that the viral 2A protease (2Apro) activity is a key factor in regulating Hsp27/hnRNP A1 relocalization. Hsp27S78A dramatically decreases the IRES activity and viral replication, which are partially reduced by Hsp27S82A. However, Hsp27S15A displays the same activity as the wild-type Hsp27. Peptide S78 potently suppresses EV-A71 protein translation and reproduction through blockage of EV-A71-induced Hsp27 phosphorylation and Hsp27/hnRNP A1 relocalization. A point mutation (S78A) on S78 impairs its inhibitory functions on Hsp27/hnRNP A1 relocalization and viral replication. Taken together, we demonstrate the importance of Ser78 phosphorylation of Hsp27 regulated by virus infection in nuclear translocation, hnRNP A1 cytosol relocation, and viral replication, suggesting a new path (such as peptide S78) for target-based antiviral strategy.


Assuntos
Enterovirus Humano A , Proteínas de Choque Térmico HSP27 , Ribonucleoproteína Nuclear Heterogênea A1 , Replicação Viral , Enterovirus Humano A/efeitos dos fármacos , Enterovirus Humano A/fisiologia , Enterovirus Humano A/genética , Fosforilação , Humanos , Replicação Viral/efeitos dos fármacos , Ribonucleoproteína Nuclear Heterogênea A1/metabolismo , Ribonucleoproteína Nuclear Heterogênea A1/genética , Proteínas de Choque Térmico HSP27/metabolismo , Proteínas de Choque Térmico HSP27/genética , Infecções por Enterovirus/virologia , Infecções por Enterovirus/metabolismo , Antivirais/farmacologia , Proteínas Virais/metabolismo , Proteínas Virais/genética , Serina/metabolismo , Células HeLa , Biossíntese de Proteínas , Cisteína Endopeptidases/metabolismo , Cisteína Endopeptidases/genética , Chaperonas Moleculares/metabolismo , Chaperonas Moleculares/genética , Proteínas de Choque Térmico
14.
Cell Rep Med ; 5(7): 101624, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38942021

RESUMO

Prior studies indicate no correlation between the gut microbes of healthy first-degree relatives (HFDRs) of patients with Crohn's disease (CD) and the development of CD. Here, we utilize HFDRs as controls to examine the microbiota and metabolome in individuals with active (CD-A) and quiescent (CD-R) CD, thereby minimizing the influence of genetic and environmental factors. When compared to non-relative controls, the use of HFDR controls identifies fewer differential taxa. Faecalibacterium, Dorea, and Fusicatenibacter are decreased in CD-R, independent of inflammation, and correlated with fecal short-chain fatty acids (SCFAs). Validation with a large multi-center cohort confirms decreased Faecalibacterium and other SCFA-producing genera in CD-R. Classification models based on these genera distinguish CD from healthy individuals and demonstrate superior diagnostic power than models constructed with markers identified using unrelated controls. Furthermore, these markers exhibited limited discriminatory capabilities for other diseases. Finally, our results are validated across multiple cohorts, underscoring their robustness and potential for diagnostic and therapeutic applications.


Assuntos
Doença de Crohn , Microbioma Gastrointestinal , Humanos , Doença de Crohn/microbiologia , Doença de Crohn/genética , Feminino , Masculino , Adulto , Microbioma Gastrointestinal/genética , Fezes/microbiologia , Família , Pessoa de Meia-Idade , Estudos de Casos e Controles , Ácidos Graxos Voláteis/metabolismo , Adulto Jovem , Metaboloma , Microbiota/genética
15.
Neurochem Int ; 178: 105792, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38880230

RESUMO

Astrocytes, the predominant glial cells in the central nervous system (CNS), play diverse roles including metabolic support for neurons, provision of neurotrophic factors, facilitation of synaptic neurotransmitter uptake, regulation of ion balance, and involvement in synaptic formation. The accumulation of lipids has been noted in various neurological conditions, yet the response of astrocytes to lipid-rich environments remains unclear. In this study, primary astrocytes isolated from the neonatal rat cortex were exposed to a lipid mixture (LM) comprising cholesterol and various fatty acids to explore their reaction. Our results showed that astrocyte viability remained unchanged following 24 h of 5% or 10% LM treatment. However, exposure to LM for 96 h resulted in reduced cell viability. In addition, LM treatment led to the accumulation of lipid droplets (LDs) in astrocytes, with LD size increasing over prolonged exposure periods. Following 24 h of LM treatment and then 48 h in fresh medium, a significant reduction in intracellular LD size was observed in cultures treated with 5% LM, while no change occurred in cultures exposed to 10% LM. Yet, exposure to 10% LM for 24 h significantly increased the expression of the cholesterol efflux regulatory protein/ATP-binding cassette transporter (ABCA1) gene, responsible for intracellular cholesterol efflux, resulting in reduced cholesterol content within astrocytes. Moreover, LM exposure led to decreased mitochondrial membrane potential (MMP) and increased levels of mature apoptosis-inducing factor (AIF). The smaller LDs were observed to co-localize with microtubule-associated protein 1A/1 B light chain 3 B (LC3) and lysosomal-associated membrane protein-1 (LAMP-1) in LM-treated astrocytes, coinciding with lysosomal acidification. These results indicate that the continuous buildup of LDs in astrocytes residing in lipid-enriched environments may be attributed to disruptions caused by LM in mitochondrial and lysosomal functions. Such disruptions could potentially impede the supportive role of astrocytes in neuronal function.


Assuntos
Astrócitos , Gotículas Lipídicas , Mitocôndrias , Animais , Astrócitos/metabolismo , Astrócitos/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Ratos , Gotículas Lipídicas/metabolismo , Gotículas Lipídicas/efeitos dos fármacos , Células Cultivadas , Ratos Sprague-Dawley , Animais Recém-Nascidos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Colesterol/metabolismo , Lipídeos , Potencial da Membrana Mitocondrial/efeitos dos fármacos
16.
Nat Commun ; 15(1): 3782, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710678

RESUMO

Thermoelectrics have great potential for use in waste heat recovery to improve energy utilization. Moreover, serving as a solid-state heat pump, they have found practical application in cooling electronic products. Nevertheless, the scarcity of commercial Bi2Te3 raw materials has impeded the sustainable and widespread application of thermoelectric technology. In this study, we developed a low-cost and earth-abundant PbS compound with impressive thermoelectric performance. The optimized n-type PbS material achieved a record-high room temperature ZT of 0.64 in this system. Additionally, the first thermoelectric cooling device based on n-type PbS was fabricated, which exhibits a remarkable cooling temperature difference of ~36.9 K at room temperature. Meanwhile, the power generation efficiency of a single-leg device employing our n-type PbS material reaches ~8%, showing significant potential in harvesting waste heat into valuable electrical power. This study demonstrates the feasibility of sustainable n-type PbS as a viable alternative to commercial Bi2Te3, thereby extending the application of thermoelectrics.

17.
J Affect Disord ; 358: 52-60, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38703907

RESUMO

BACKGROUND: Adolescence involves a period of swift change, including the development of personality vulnerabilities (i.e., dependency and self-criticism) that act as transdiagnostic factors to psychopathology. Over the past several decades, numerous short revisions have condensed the Depressive Experiences Questionnaire (DEQ) into more efficient measures of personality vulnerability. Prior research has investigated the psychometric properties of the short DEQs in adult and clinical samples. However, there has been insufficient exploration within adolescents, who are in addition marked by fluctuating personality vulnerabilities. METHOD: A representative large sample of adolescents and emerging adults in China aged 10 to 25 (N = 23,953) was administered five short DEQs, including the Revised DEQ (RevDEQ), Reconstructed DEQ (RecDEQ), Theoretical DEQ-21/12 (TDEQ-21/12) and adolescent DEQ (DEQ-A). The data was evaluated for internal consistency and criterion-related validity, while factor structure and measurement invariances across gender and age groups were analyzed by confirmatory factor analysis (CFA). A subset of the original sample (N = 2874) was retested after six months and analyzed for test-retest reliability and cross-time invariance. RESULT: CFA of the TDEQ-21/12 and RecDEQ supported the intended two-factor model. Good criterion-related validity, internal consistency and test-retest reliability for these three versions were found. Satisfying measurement invariances across gender, time, and age groups were established. LIMITATION: The study's scope was confined to non-clinical adolescent populations within China, highlighting a gap in cross-cultural and clinical applicability. CONCLUSION: The present study supports the use of the TDEQ-21/12 and RecDEQ as valid and concise instruments for measuring Chinese adolescent personality vulnerability.


Assuntos
Psicometria , Humanos , Adolescente , Feminino , Masculino , China , Reprodutibilidade dos Testes , Inquéritos e Questionários/normas , Criança , Adulto Jovem , Depressão/diagnóstico , Depressão/psicologia , Adulto , Análise Fatorial , População do Leste Asiático
18.
Micromachines (Basel) ; 15(4)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38675253

RESUMO

To obtain precise positional information, in this study, we propose an adaptive expectation-maximization (EM)-based Kalman filter (KF)/finite impulse response (FIR) integrated filter for inertial navigation system (INS)-based posture capture of human upper limbs. Initially, a data fusion model for wrist and elbow position is developed. Subsequently, the Mahalanobis distance is utilized to evaluate the performance of the filter. The integrated filter employs the EM-based KF to enhance noise estimation accuracy when the performance of KF declines. Conversely, upon deterioration in the performance of the EM-based KF, which is evaluated using the Mahalanobis distance, the FIR filter is employed to maintain the effectiveness of the data fusion filter. This research utilizes the proposed EM-based KF/FIR integrated filter to ascertain wrist and elbow positions. The empirical results demonstrate the proficiency of the proposed approach in estimating these positions, thereby overcoming the challenge and highlighting its inherent effectiveness.

19.
Sci Bull (Beijing) ; 69(11): 1728-1737, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38688741

RESUMO

Thermoelectric materials have a wide range of application because they can be directly used in refrigeration and power generation. And the Bi2Te3 stand out because of its excellent thermoelectric performance and are used in commercial thermoelectric devices. However, n-type Bi2Te3 has seriously hindered the development of Bi2Te3-based thermoelectric devices due to its weak mechanical properties and inferior thermoelectric performance. Therefore, it is urgent to develop a high-performance n-type Bi2Te3 polycrystalline. In this work, we employed interstitial Cu and the hot deformation process to optimize the thermoelectric properties of Bi2Te2.7Se0.3, and a high-performance thermoelectric module was fabricated based on this material. Our combined theoretical and experimental effort indicates that the interstitial Cu reduce the defect density in the matrix and suppresses the donor-like effect, leading to a lattice plainification effect in the material. In addition, the two-step hot deformation process significantly improves the preferred orientation of the material and boosts the mobility. As a result, a maximum ZT of 1.27 at 373 K and a remarkable high ZTave of 1.22 across the temperature range of 300-425 K are obtained. The thermoelectric generator (TEG, 7-pair) and thermoelectric cooling (TEC, 127-pair) modules were fabricated with our n-type textured Cu0.01Bi2Te2.7Se0.3 coupled with commercial p-type Bi2Te3. The TEC module demonstrates superior cooling efficiency compared with the commercial Bi2Te3 device, achieving a ΔT of 65 and 83.4 K when the hot end temperature at 300 and 350 K, respectively. In addition, the TEG module attains an impressive conversion efficiency of 6.5% at a ΔT of 225 K, which is almost the highest value among the reported Bi2Te3-based TEG modules.

20.
Int J Biol Macromol ; 269(Pt 2): 131720, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38677692

RESUMO

The human nervous system is an incredibly intricate physiological network, and neural cells lack the ability to repair and regenerate after a brain injury. 3-dimensional (3D) bioprinting technology offers a promising strategy for constructing biomimetic organ constructs and in vitro brain/disease models. The bioink serves as a pivotal component that emulates the microenvironment of biomimetic construct and exerts a profound influence on cellular behaviors. In this study, a series of mechanically adjustable and dual crosslinking bioinks were developed using photocrosslinkable methacrylated silk fibroin (SilMA) in combination with the ionic crosslinking material, pectin, or pectin methacryloyl (PecMA) with silk fibroin (SF) supplementation. SilMA/pectin exhibited superior properties, with SilMA providing biocompatibility and adjustable mechanical properties, while the addition of pectin enhanced printability. The porous structure supported neural cell growth, and 15 % SilMA/0.5 % pectin bioinks displayed excellent printability and shape fidelity. Neural stem/progenitor cells (NSPCs)-loaded bioinks were used to construct a 3D brain model, demonstrating sustained vitality and high neuronal differentiation without the need for growth factors. The SilMA/pectin bioinks demonstrated adjustable mechanical properties, favorable biocompatibility, and an environment highly conducive to neural induction, offering an alternative approach for neural tissue engineering applications or in vitro brain models.


Assuntos
Bioimpressão , Fibroínas , Células-Tronco Neurais , Pectinas , Impressão Tridimensional , Esferoides Celulares , Pectinas/química , Fibroínas/química , Células-Tronco Neurais/citologia , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/metabolismo , Bioimpressão/métodos , Esferoides Celulares/citologia , Alicerces Teciduais/química , Animais , Engenharia Tecidual/métodos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Humanos , Diferenciação Celular/efeitos dos fármacos , Tinta
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