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1.
Diabetes Metab Res Rev ; 40(1): e3709, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37545374

RESUMEN

Diabetes mellitus (DM) has been proposed to be positively associated with breast cancer (BCa) risk due to shared risk factors, metabolic dysfunction, and the use of antidiabetic medications. We conducted a systematic review and meta-analysis to evaluate the association between DM and BCa risk. We searched PubMed, Embase, and Web of Science for cohort and case-control studies assessing the association between DM and BCa published before 10 December 2021. Two reviewers independently screened the studies for inclusion, abstracted article data, and rated study quality. Random effects models were used to estimate summary risk ratios (RRs) and 95% confidence intervals (CIs). From 8396 articles identified in the initial search, 70 independent studies were included in the meta-analysis. DM was associated with an overall increased risk of BCa (RR = 1.20, 95% CI: 1.11-1.29). The 24 case-control studies demonstrated a stronger association (RR = 1.26, 95% CI: 1.13-1.40) than the 46 cohort studies (RR = 1.15, 95% CI: 1.05-1.27). Studies reporting risk by menopausal status found that postmenopausal women had an elevated risk of developing BCa (RR = 1.12, 95% CI: 1.07-1.17). No association between DM and BCa risk was observed among premenopausal women (RR = 0.95, 95% CI: 0.85-1.05). In addition, DM was associated with significantly increased risks of oestrogen receptor (ER)+ (RR = 1.09, 95% CI: 1.00-1.20), ER- (RR = 1.16, 95% CI: 1.04-1.30), and triple negative BCa (RR = 1.41, 95% CI: 1.01-1.96). The association estimate for human epidermal growth factor 2-positive BCa was also positive (RR = 1.21, 95% CI: 0.52-2.82), but the CI was wide and crossed the null. Our meta-analysis confirms a modest positive association between DM and BCa risk. In addition, our results suggest that the association between DM and BCa may be modified by menopausal status, and that DM may be differentially associated with BCa subtypes defined by receptor status. Additional studies are warranted to investigate the mechanisms underlying these associations and any influence of DM on BCa receptor expression.


Asunto(s)
Neoplasias de la Mama , Diabetes Mellitus Tipo 2 , Humanos , Femenino , Incidencia , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/etiología , Factores de Riesgo , Diabetes Mellitus Tipo 2/complicaciones , Estudios de Cohortes
2.
J Appl Microbiol ; 135(8)2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39134510

RESUMEN

Tuberculosis (TB) is a serious and fatal disease caused by Mycobacterium tuberculosis (Mtb). The World Health Organization reported an estimated 1.30 million TB-related deaths in 2022. The escalating prevalence of Mtb strains classified as being multi-, extensively, extremely, or totally drug resistant, coupled with the decreasing efficacies of conventional therapies, necessitates the development of novel treatments. As viruses that infect Mycobacterium spp., mycobacteriophages may represent a strategy to combat and eradicate drug-resistant TB. More exploration is needed to provide a comprehensive understanding of mycobacteriophages and their genome structure, which could pave the way toward a definitive treatment for TB. This review focuses on the properties of mycobacteriophages, their potential in diagnosing and treating TB, the benefits and drawbacks of their application, and their use in human health. Specifically, we summarize recent research on mycobacteriophages targeted against Mtb infection and newly developed mycobacteriophage-based tools to diagnose and treat diseases caused by Mycobacterium spp. We underscore the urgent need for innovative approaches and highlight the potential of mycobacteriophages as a promising avenue for developing effective diagnosis and treatment to combat drug-resistant Mycobacterium strains.


Asunto(s)
Micobacteriófagos , Mycobacterium tuberculosis , Tuberculosis , Micobacteriófagos/genética , Micobacteriófagos/fisiología , Humanos , Tuberculosis/tratamiento farmacológico , Tuberculosis/microbiología , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Antituberculosos/uso terapéutico , Antituberculosos/farmacología
3.
Angew Chem Int Ed Engl ; 62(22): e202301382, 2023 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-36988556

RESUMEN

Developing a novel tool capable of real-time monitoring and simultaneously quantifying of both intra/extracellular chemical signals across the large-scale brain is the key bottleneck for understanding the interactions between the molecules inside and outside neurons. Here we built up a high-density intra/extracellular optophysiology platform, together with developing two probes for specific recognition of L-cysteine (Cys) and dopamine (DA), for simultaneously quantifying of both intracellular Cys and extracellular DA with high selectivity and accuracy across the brain of freely moving animals, as well as recording electrical signals. Using this powerful tool, it was found that intracellular Cys regulated extracellular DA through inducing the expression of tyrosine hydroxylase in the depressed mice brain. We also established the functional networks of Cys and DA across 32 brain regions in freely moving animals. More importantly, it was discovered that depression reduced the correlations between adjacent brain regions, which was recovered by the treatment of N-acetyl-l-cysteine.


Asunto(s)
Encéfalo , Dopamina , Ratones , Animales , Encéfalo/metabolismo , Dopamina/química , Acetilcisteína , Neuronas/metabolismo
4.
Eur Radiol ; 32(12): 8540-8549, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35731290

RESUMEN

OBJECTIVES: To explore the utility of radiomics and deep learning model in assessing the risk factors for sepsis after flexible ureteroscopy lithotripsy (FURL) or percutaneous nephrolithotomy (PCNL) in patients with ureteral calculi. METHODS: This retrospective analysis included 847 patients with treatment-naive proximal ureteral calculi who received FURL or PCNL. All participants were preoperatively conducted non-contrast computed tomography scans, and relevant clinical information was meanwhile collected. After propensity score matching, the radiomics model was established to predict the onset of sepsis. A deep learning model was also adapted to further improve the prediction accuracy. Performance of these trained models was verified in another independent external validation set including 40 cases of ureteral calculi patients. RESULTS: The overall incidence of sepsis after FURL or PCNL was 5.9%. The least absolute shrinkage and selection operator (LASSO) regression analysis revealed 26 predictive variables, with an overall AUC of 0.881 (95% CI, 0.813-0.931) and an AUC of 0.783 (95% CI, 0.766-0.801) in external validation cohort. Judicious adaption of a deep neural network (DNN) model to our dataset improved the AUC to 0.920 (95% CI, 0.906-0.933) in the internal validation. To eliminate the overfitting, external validation was carried out for DNN model (AUC = 0.874 (95% CI, 0.858-0.891)). CONCLUSIONS: The DNN was more effective than the LASSO model in revealing risk factors for sepsis after FURL or PCNL in single ureteral calculi patients, and females are more susceptible to sepsis than males. Deep learning models have the potential to act as gatekeepers to facilitate patient stratification. KEY POINTS: • Both the least absolute shrinkage and selection operator (LASSO) and deep neural network (DNN) models were shown to be effective in sepsis prediction. • The DNN model achieved superior prediction capability, with an AUC of 0.920 (95% CI, 0.906-0.933). • DNN-assisted model has potential to serve as a gatekeeper to facilitate patient stratification.


Asunto(s)
Litotricia , Sepsis , Cálculos Ureterales , Masculino , Femenino , Humanos , Cálculos Ureterales/diagnóstico por imagen , Cálculos Ureterales/cirugía , Ureteroscopía/efectos adversos , Ureteroscopía/métodos , Estudios Retrospectivos , Litotricia/efectos adversos , Litotricia/métodos , Sepsis/epidemiología , Sepsis/etiología , Factores de Riesgo , Redes Neurales de la Computación , Resultado del Tratamiento
5.
Nanotechnology ; 33(48)2022 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-35981442

RESUMEN

Perovskite nanowires (NWs) have attracted considerable interest because of their excellent polarization properties. In this work, we first synthesized colloidal lead halide CsPbBr3NWs with suitable lengths and excellent polarization performance by the method of the thermal injection. By embedding the NWs in polyvinyl alcohol (PVA) to prepare practical a polymer composite and combining it with the mechanical stretching method, we achieved films with higher polarizing properties. The optimized stretched composite film achieved a polarization degree of 0.4992, which is superior to that of the unstretched one. The stretched PVA molecules are arranged in a straight line, which absorbs the polarized light parallel to the alignment direction, and only allows the polarized light in the vertical direction to pass through. Therefore, the arrangement of the spin-coated NWs combined with the arrangement direction of the PVA molecules led to an improvement in the polarization performance of the composite film. The NWs-PVA-stretched composite films will show important application value in the manufacture of next-generation polarization-sensitive optoelectronic devices and other fields.

6.
Inorg Chem ; 58(9): 6328-6335, 2019 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-31013059

RESUMEN

Phosphine-functionalized N-heterocyclic carbene (NHC) ligands are known to complex group 11 metal centers to form multinuclear complexes with photoluminescence properties. This study reports a structurally rigid ortho-substituted dipyrido-annulated NHC with T-shape coordination geometry and its di- and tetranuclear gold(I) complexes. The free ligand as well as all metal complexes are found luminescent at room temperature and phosphorescent at 77 K. Although metal d10-d10 interactions are evident based on their solid-state structures, their effect on the photoemission is limited, most likely due to the weak coordination of the ligand to the metal centers in solution.

8.
J Biomol Struct Dyn ; : 1-19, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38229237

RESUMEN

Ferroptosis, characterized by iron accumulation and lipid peroxidation, leads to cell death. Growing evidence suggests the involvement of ferroptosis in sarcopenia. However, the fundamental ferroptosis-related genes (FRGs) for sarcopenia diagnosis, prognosis, and therapy remain elusive. This study aimed to identify molecular biomarkers of ferroptosis in sarcopenia patients. Gene expression profiles were obtained from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) between normal and sarcopenia samples were identified using the 'limma' package in R software. FRGs were extracted from GeneCards and FerrDB databases. Functional enrichment analysis determined the roles of DEGs using the 'clusterProfiler' package. A protein-protein network was constructed using Cytoscape software. Immune infiltration analysis and receiver operating characteristic (ROC) analysis were performed. mRNA-miRNA, mRNA-TF, and mRNA-drug interactions were predicted using ENCORI, hTFtarget, and CHIPBase databases. The network was visualized using Cytoscape. We identified 46 FRGs in sarcopenia. Functional enrichment analysis revealed their involvement in critical biological processes, including responses to steroid hormones and glucocorticoids. KEGG enrichment analysis implicated pathways such as carbon metabolism, ferroptosis, and glyoxylate in sarcopenia. Totally, 11 hub genes were identified, and ROC analysis demonstrated their potential as sensitive and specific markers for sarcopenia in both datasets. Additionally, differences in immune cell infiltration were observed between normal and sarcopenia samples. The hub genes identified in this study are closely associated with ferroptosis in sarcopenia and can effectively differentiate sarcopenia from controls. CDKN1A, CS, DLD, FOXO1, HSPB1, LDHA, MDH2, and YWHAZ show high sensitivity and specificity for sarcopenia diagnosis.Communicated by Ramaswamy H. Sarma.

9.
Nat Commun ; 15(1): 3246, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38622137

RESUMEN

Simultaneously quantifying mitochondrial Cu+ and Cu2+ levels is crucial for evaluating the molecular mechanisms of copper accumulation-involved pathological processes. Here, a series of molecules containing various diacetylene derivatives as Raman reporters are designed and synthesized, and the alkyne-tagged SERS probe is created for determination Cu+ and Cu2+ with high selectivity and sensitivity. The developed SERS probe generates well-separated distinguishable Raman fingerprint peaks with built-in corrections in the cellular silent region, resulting in accurate quantification of Cu+ and Cu2+. The present probe demonstrates high tempo-spatial resolution for real-time imaging and simultaneously quantifying mitochondrial Cu+ and Cu2+ with long-term stability benefiting from the probe assembly with designed Au-C≡C groups. Using this powerful tool, it is found that mitochondrial Cu+ and Cu2+ increase during ischemia are associated with breakdown of proteins containing copper as well as conversion of Cu+ and Cu2+. Meanwhile, we observe that parts of Cu+ and Cu2+ are transported out of neurons by ATPase. More importantly, cuproptosis in neurons is found including the oxidative stress process caused by the conversion of Cu+ to Cu2+, which dominates at the early stage (<9 h), and subsequent proteotoxic stress. Both oxidative and proteotoxic stresses contribute to neuronal death.


Asunto(s)
Alquinos , Cobre , Espectrometría Raman/métodos , Oro , Transporte Biológico
10.
Carbohydr Polym ; 329: 121530, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38286525

RESUMEN

Separators are indispensable components in lithium-ion batteries (LIBs), providing efficient pathways for lithium ions to travel and isolating the positive and negative electrodes to avoid short circuits. However, traditional polyolefin-based separators exhibit inferior electrolyte affinities, limited porosities, and low thermal stabilities. In this study, a novel method was developed to prepare chitosan micro/nanofiber membranes as LIB separators using natural materials. The pore sizes of the chitosan micro/nanofibers separators were modulated by changing the diameters of the chitosan fibers. The results demonstrated that the chitosan nanofiber separators (CSNFs) had superior electrolyte uptake (281 %), excellent thermal dimensional stability, and electrochemical performance in LiFePO4/Li half-cell, as indicated by the higher discharge capacity after 100 cycles, and higher rate capacity than commercial Celgard2325 separator. This study paves the way for the fabrication of eco-efficient and environment-friendly separators for high-performance LIBs.

11.
Int J Biol Macromol ; 254(Pt 2): 127912, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37939763

RESUMEN

The repair of bone defects using grafts is commonly employed in clinical practice. However, the risk of infection poses a significant concern. Tissue engineering scaffolds with antibacterial functionalities offer a better approach for bone tissue repair. In this work, firstly, two kinds of nanoparticles were prepared using chitosan to complex with ciprofloxacin and BMP-2, respectively. The ciprofloxacin complex nanoparticles improved the dissolution efficiency of ciprofloxacin achieving a potent antibacterial effect and cumulative release reached 95 % in 7 h. For BMP-2 complexed nanoparticles, the release time points can be programmed at 80 h, 100 h or 180 h by regulating the number of coating chitosan layers. Secondly, a functional scaffold was prepared by combining the two nanoparticles with chitosan nanofibers. The microscopic nanofiber structure of the scaffold with 27.28 m2/g specific surface area promotes cell adhesion, high porosity provides space for cell growth, and facilitates drug loading and release. The multifunctional scaffold exhibits programmed release function, and has obvious antibacterial effect at the initial stage of implantation, and releases BMP-2 to promote osteogenic differentiation of mesenchymal stem cells after the antibacterial effect ends. The scaffold is expected to be applied in clinical bone repair and graft infection prevention.


Asunto(s)
Quitosano , Nanofibras , Nanopartículas , Osteogénesis , Nanofibras/química , Quitosano/química , Preparaciones de Acción Retardada/farmacología , Ciprofloxacina/farmacología , Regeneración Ósea , Ingeniería de Tejidos , Andamios del Tejido/química , Antibacterianos/farmacología , Nanopartículas/química
12.
Exp Hematol Oncol ; 13(1): 47, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664743

RESUMEN

Enhanced cellular therapy has emerged as a novel concept following the basis of cellular therapy. This treatment modality applied drugs or biotechnology to directly enhance or genetically modify cells to enhance the efficacy of adoptive cellular therapy (ACT). Drugs or biotechnology that enhance the killing ability of immune cells include immune checkpoint inhibitors (ICIs) / antibody drugs, small molecule inhibitors, immunomodulatory factors, proteolysis targeting chimera (PROTAC), oncolytic virus (OV), etc. Firstly, overcoming the inhibitory tumor microenvironment (TME) can enhance the efficacy of ACT, which can be achieved by blocking the immune checkpoint. Secondly, cytokines or cytokine receptors can be expressed by genetic engineering or added directly to adoptive cells to enhance the migration and infiltration of adoptive cells to tumor cells. Moreover, multi-antigen chimeric antigen receptors (CARs) can be designed to enhance the specific recognition of tumor cell-related antigens, and OVs can also stimulate antigen release. In addition to inserting suicide genes into adoptive cells, PROTAC technology can be used as a safety switch or degradation agent of immunosuppressive factors to enhance the safety and efficacy of adoptive cells. This article comprehensively summarizes the mechanism, current situation, and clinical application of enhanced cellular therapy, describing potential improvements to adoptive cellular therapy.

13.
Int J Surg ; 110(5): 2992-3007, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38445538

RESUMEN

BACKGROUND: Image-guided surgery (IGS) refers to surgery navigated by medical imaging technology, helping doctors better clarify tumor boundaries, identify metastatic lymph nodes and preserve surrounding healthy tissue function. Recent studies have provided expectable momentum of the application of IGS in prostate cancer (PCa). The authors aim to comprehensively construct a bibliometric analysis of the application of IGS in PCa. METHOD: The authors searched publications related to application of IGS in PCa from 2013 to 2023 on the web of science core collection (WoSCC) databases. VOSviewer, CiteSpace, and R package 'bibliometrix' were used for bibliometric analysis. RESULTS: Two thousand three eighty-nine articles from 75 countries and 2883 institutions led by the United States were included. The number of publications related to the application of IGS in PCa kept high in the last decade. Johns Hopkins University is the top research institutions. Journal of Nuclear Medicine has the highest popularity as the selection of journal and co-cited journal. Pomper Martin G. had published the most paper. Ali Afshar-Oromieh was co-cited most frequently. The clinical efficacy of PSMA-PET/CT in PCa diagnosis and treatment are main topics in this research field, with emerging focuses on the use of fluorescence imaging guidance technology in PCa. 'PSMA' and 'PET/CT' are the main keywords as long-term research hotspots. CONCLUSION: This study is the first bibliometric analysis of researches on application of IGS in PCa with three recognized bibliometric software, providing an objective description and comprehensive guidance for the future relevant investigations.


Asunto(s)
Bibliometría , Neoplasias de la Próstata , Cirugía Asistida por Computador , Humanos , Masculino , Neoplasias de la Próstata/cirugía , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Cirugía Asistida por Computador/métodos , Prostatectomía/métodos , Prostatectomía/estadística & datos numéricos
14.
Front Immunol ; 15: 1395047, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38694500

RESUMEN

The emergence of resistance to prostate cancer (PCa) treatment, particularly to androgen deprivation therapy (ADT), has posed a significant challenge in the field of PCa management. Among the therapeutic options for PCa, radiotherapy, chemotherapy, and hormone therapy are commonly used modalities. However, these therapeutic approaches, while inducing apoptosis in tumor cells, may also trigger stress-induced premature senescence (SIPS). Cellular senescence, an entropy-driven transition from an ordered to a disordered state, ultimately leading to cell growth arrest, exhibits a dual role in PCa treatment. On one hand, senescent tumor cells may withdraw from the cell cycle, thereby reducing tumor growth rate and exerting a positive effect on treatment. On the other hand, senescent tumor cells may secrete a plethora of cytokines, growth factors and proteases that can affect neighboring tumor cells, thereby exerting a negative impact on treatment. This review explores how radiotherapy, chemotherapy, and hormone therapy trigger SIPS and the nuanced impact of senescent tumor cells on PCa treatment. Additionally, we aim to identify novel therapeutic strategies to overcome resistance in PCa treatment, thereby enhancing patient outcomes.


Asunto(s)
Senescencia Celular , Resistencia a Antineoplásicos , Neoplasias de la Próstata , Humanos , Senescencia Celular/efectos de los fármacos , Masculino , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/terapia , Neoplasias de la Próstata/metabolismo , Animales
15.
Bioorg Med Chem Lett ; 23(23): 6432-5, 2013 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-24119555

RESUMEN

A novel class of di-substituted cinnamic hydroxamic acid derivatives containing urea or thiourea unit was designed, synthesized and evaluated as HDAC inhibitors. All tested compounds demonstrated significant HDAC inhibitory activities and anti-proliferative effects against diverse human tumor cell lines. Among them, 7l exhibited most potent pan-HDAC inhibitory activity, with an IC50 value of 130 nM. It also showed strong cellular inhibition against diverse cell lines including HCT-116, MCF-7, MDB-MB-435 and NCI-460, with GI50 values of 0.35, 0.22, 0.51 and 0.48 µM, respectively.


Asunto(s)
Cinamatos/química , Cinamatos/farmacología , Inhibidores de Histona Desacetilasas/química , Inhibidores de Histona Desacetilasas/farmacología , Ácidos Hidroxámicos/química , Ácidos Hidroxámicos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cinamatos/síntesis química , Diseño de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Células HCT116 , Inhibidores de Histona Desacetilasas/síntesis química , Humanos , Ácidos Hidroxámicos/síntesis química , Células MCF-7 , Modelos Moleculares , Relación Estructura-Actividad , Tiourea/análogos & derivados , Tiourea/química , Tiourea/farmacología , Urea/análogos & derivados , Urea/química , Urea/farmacología
16.
Polymers (Basel) ; 15(18)2023 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-37765508

RESUMEN

With the development of portable devices and wearable devices, there is a higher demand for high-energy density and light lithium-ion batteries (LIBs). The separator is a significant component directly affecting the performance of LIBs. In this paper, a thin and porous chitosan nanofiber separator was successfully fabricated using the simple ethanol displacement method. The thickness of the CME15 separator was about half that of mainstream commercial Celgard2325 separators. Owing to its inherent polarity and high porosity, the obtained CME15 separator achieved a small contact angle (18°) and excellent electrolyte wettability (324% uptake). The CME15 separator could maintain excellent thermal dimensional stability at 160 °C. Furthermore, the CME15 separator-based LIBs exhibited excellent cycling performance after 100 cycles (117 mAh g-1 at 1 C). The present work offers a perspective on applying a chitosan nanofiber separator in light and high-performance lithium-ion batteries (LIBs).

17.
3D Print Addit Manuf ; 10(4): 808-815, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37609586

RESUMEN

Fused filament fabrication is one of the most desired thermal plastic additive manufacturing processes because of its ability to fabricate complex objects with high accessibility. However, due to the extrusion track-based direct write process mechanism, parts built using this method exhibit anisotropic mechanical properties. In this work, an in-process laser heating method is introduced to heal interface adhesion between adjacent deposited tracks by increasing the interface temperature to promote polymer reptation and enhance bonding strength of the interface of adjacent tracks. With the use of laser heating induced interface healing, the measured flexural strength between adjacent tracks in the same layer increased and exceeded that of the control sample tested along the track direction. The effect of laser on interface healing was also verified by investigating the load-displacement curve and morphology analysis of the fractured surface.

18.
Polymers (Basel) ; 15(21)2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37959883

RESUMEN

Extrusion-based polymer 3D printing induces shear strains within the material, influencing its rheological and mechanical properties. In materials like polyvinylidene difluoride (PVDF), these strains stretch polymer chains, leading to increased crystallinity and improved piezoelectric properties. This study demonstrates a 400% enhancement in the piezoelectric property of extrusion-printed PVDF by introducing additional shear strains during the printing process. The continuous torsional shear strains, imposed via a rotating extrusion nozzle, results in additional crystalline ß-phases, directly impacting the piezoelectric behavior of the printed parts. The effect of the nozzle's rotational speed on the amount of ß-phase formation is characterized using FTIR. This research introduces a new direction in the development of polymer and composite 3D printing, where in-process shear strains are used to control the alignment of polymer chains and/or in-fill phases and the overall properties of printed parts.

19.
J Exp Psychol Gen ; 152(7): 1937-1950, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36821341

RESUMEN

Prioritizing attention to reward-predictive items is critical for survival, but challenging because these items rarely appear in the same feature or within the same environment. However, whether attention selection can be adaptively tuned to items that matched the context-dependent, relative feature of previously rewarded items remains largely unknown. In four experiments (N = 40 per experiment), we trained participants to learn the color-reward association and then adopted visual search tasks in which the color of a singleton distractor matched either the feature value (e.g., red or yellow) or feature relationship (i.e., redder or yellower) of previously rewarded colors. We consistently found enhanced attentional capture by a singleton distractor when it was relationally matched to the high reward compared with the low reward relationship, in addition to observing the typical effect of learned value on singletons matching the previously rewarded colors. Our findings provide novel evidence for the flexibility of value-driven attention via feature relationship, which is particularly useful given the changeable sensory inputs in real-world searches. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Asunto(s)
Aprendizaje , Recompensa , Humanos , Tiempo de Reacción
20.
Polymers (Basel) ; 15(9)2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37177367

RESUMEN

Material extrusion-based polymer 3D printing, one of the most commonly used additive manufacturing processes for thermoplastics and composites, has drawn extensive attention due to its capability and cost effectiveness. However, the low surface finish quality of the printed parts remains a drawback due to the nature of stacking successive layers along one direction and the nature of rastering of the extruded tracks of material. In this work, an in-process thermal radiation-assisted, surface reflow method is demonstrated that significantly improves the surface finish of the sidewalls of printed parts. It is observed that the surface finish of the printed part is drastically improved for both flat and curved surfaces. The effect of surface reflow on roughness reduction was characterized using optical profilometry and scanning electron microscopy (SEM), while the local heated spot temperature was quantified using a thermal camera.

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