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1.
BMC Oral Health ; 24(1): 872, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39090625

RESUMEN

BACKGROUND: This study quantitatively analyzed the anatomic structure of the alveolar bone in the maxillary molar region at three potential locations for Temporary Anchorage Device (TAD) placement. Additionally, the study compared the variability in this region across different age groups, sagittal skeletal patterns, vertical facial types, and sexes. METHODS: In this retrospective cone-beam computed tomography study, the buccal alveolar bone was analyzed in the posterior molar area of 200 patients, the measurement items include buccal alveolar bone height, alveolar bone thickness, interradicular distance, and maxillary retromolar space. RESULTS: Buccal alveolar height was greatest in the U56 region. The interradicular space was largest in the U56 region and increased from the alveolar crest to the sinus floor. Buccal alveolar bone thickness was highest in the U67 region and generally increased from the alveolar crest to the sinus floor. The maxillary retromolar space gradually increased from the alveolar crest to the root apex. CONCLUSIONS: TADs are safest when placed in the buccal area between the maxillary second premolar and the first molar, particularly at the 9 mm plane. The U67 region is the optimal safe zone for TAD placement for maxillary dentition distalization. TADs placement in adolescents can be challenging. Maxillary third molar extraction can be considered for maxillary dentition distalization.


Asunto(s)
Proceso Alveolar , Tomografía Computarizada de Haz Cónico , Maxilar , Diente Molar , Humanos , Tomografía Computarizada de Haz Cónico/métodos , Estudios Retrospectivos , Femenino , Masculino , Diente Molar/diagnóstico por imagen , Diente Molar/anatomía & histología , Proceso Alveolar/diagnóstico por imagen , Proceso Alveolar/anatomía & histología , Maxilar/diagnóstico por imagen , Maxilar/anatomía & histología , Adolescente , Adulto , Adulto Joven , Métodos de Anclaje en Ortodoncia/métodos , Persona de Mediana Edad
2.
Light Sci Appl ; 13(1): 185, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39128902

RESUMEN

Augmented reality (AR) displays, heralded as the next-generation platform for spatial computing, metaverse, and digital twins, empower users to perceive digital images overlaid with real-world environment, fostering a deeper level of human-digital interactions. With the rapid evolution of couplers, waveguide-based AR displays have streamlined the entire system, boasting a slim form factor and high optical performance. However, challenges persist in the waveguide combiner, including low optical efficiency and poor image uniformity, significantly hindering the long-term usage and user experience. In this paper, we first analyze the root causes of the low optical efficiency and poor uniformity in waveguide-based AR displays. We then discover and elucidate an anomalous polarization conversion phenomenon inherent to polarization volume gratings (PVGs) when the incident light direction does not satisfy the Bragg condition. This new property is effectively leveraged to circumvent the tradeoff between in-coupling efficiency and eyebox uniformity. Through feasibility demonstration experiments, we measure the light leakage in multiple PVGs with varying thicknesses using a laser source and a liquid-crystal-on-silicon light engine. The experiment corroborates the polarization conversion phenomenon, and the results align with simulation well. To explore the potential of such a polarization conversion phenomenon further, we design and simulate a waveguide display with a 50° field of view. Through achieving first-order polarization conversion in a PVG, the in-coupling efficiency and uniformity are improved by 2 times and 2.3 times, respectively, compared to conventional couplers. This groundbreaking discovery holds immense potential for revolutionizing next-generation waveguide-based AR displays, promising a higher efficiency and superior image uniformity.

3.
Ultrasound Med Biol ; 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39138026

RESUMEN

OBJECTIVES: To assess the capabilities of large language models (LLMs), including Open AI (GPT-4.0) and Microsoft Bing (GPT-4), in generating structured reports, the Breast Imaging Reporting and Data System (BI-RADS) categories, and management recommendations from free-text breast ultrasound reports. MATERIALS AND METHODS: In this retrospective study, 100 free-text breast ultrasound reports from patients who underwent surgery between January and May 2023 were gathered. The capabilities of Open AI (GPT-4.0) and Microsoft Bing (GPT-4) to convert these unstructured reports into structured ultrasound reports were studied. The quality of structured reports, BI-RADS categories, and management recommendations generated by GPT-4.0 and Bing were evaluated by senior radiologists based on the guidelines. RESULTS: Open AI (GPT-4.0) was better than Microsoft Bing (GPT-4) in terms of performance in generating structured reports (88% vs. 55%; p < 0.001), giving correct BI-RADS categories (54% vs. 47%; p = 0.013) and providing reasonable management recommendations (81% vs. 63%; p < 0.001). As the ability to predict benign and malignant characteristics, GPT-4.0 performed significantly better than Bing (AUC, 0.9317 vs. 0.8177; p < 0.001), while both performed significantly inferior to senior radiologists (AUC, 0.9763; both p < 0.001). CONCLUSION: This study highlights the potential of LLMs, specifically Open AI (GPT-4.0), in converting unstructured breast ultrasound reports into structured ones, offering accurate diagnoses and providing reasonable recommendations.

4.
Cancer Innov ; 3(4): e127, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38948249

RESUMEN

Background: Clinical studies have shown that atherosclerotic cardiovascular disease and cancer often co-exist in the same individual. The present study aimed to investigate the role of high-fat-diet (HFD)-induced obesity in the coexistence of the two diseases and the underlying mechanism in apolipoprotein E-knockout (ApoE-/-) mice. Methods: Male ApoE-/- mice were fed with a HFD or a normal diet (ND) for 15 weeks. On the first day of Week 13, the mice were inoculated subcutaneously in the right axilla with Lewis lung cancer cells. At Weeks 12 and 15, serum lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) and vascular endothelial growth factor levels were measured by enzyme-linked immunosorbent assay, and blood monocytes and macrophages were measured by fluorescence-activated cell sorting. At Week 15, the volume and weight of the local subcutaneous lung cancer and metastatic lung cancer and the amount of aortic atherosclerosis were measured. Results: At Week 15, compared with mice in the ND group, those in the HFD group had a larger volume of local subcutaneous cancer (p = 0.0004), heavier tumors (p = 0.0235), more metastatic cancer in the lungs (p < 0.0001), a larger area of lung involved in metastatic cancer (p = 0.0031), and larger areas of atherosclerosis in the aorta (p < 0.0001). At Week 12, serum LOX-1, serum vascular endothelial growth factor, and proportions of blood monocytes and macrophages were significantly higher in the HFD group than those in the ND group (p = 0.0002, p = 0.0029, p = 0.0480, and p = 0.0106, respectively); this trend persisted until Week 15 (p = 0.0014, p = 0.0012, p = 0.0001, and p = 0.0204). Conclusions: In this study, HFD-induced obesity could simultaneously promote progression of lung cancer and atherosclerosis in the same mouse. HFD-induced upregulation of LOX-1 may play an important role in the simultaneous progression of these two conditions via the inflammatory response and VEGF.

5.
Shanghai Kou Qiang Yi Xue ; 33(2): 148-155, 2024 Apr.
Artículo en Chino | MEDLINE | ID: mdl-39005090

RESUMEN

PURPOSE: The purpose of this study was to explore the expression, prognostic value and immune correlation of Cofilin 1 protein(CFL-1) in head and neck squamous cell carcinoma(HNSCC). METHODS: The expression and prognostic value of CFL-1 in head and neck squamous cell carcinoma(HNSCC) was explored in the cancer genome map database (TCGA) and gene expression total databases (GEO), and the potential immune pathway of CFL-1 in HNSCC was revealed by GESA and cibersoft analysis. The data were statistically analyzed using SPSS 26.0 software package. RESULTS: CFL-1 was significantly up-regulated in HNSCC tissue. The expression level of CFL-1 was significantly correlated with the overall survival status of HNSCC. High expression of CFL-1 was significantly associated with a lower overall survival rate. In addition, multivariate Cox survival analysis showed that CFL-1 expression was independent predictors of poor prognosis of HNSCC. GESA and cibersoft analysis showed that the imbalance of CFL-1 expression affected multiple signal pathways and infiltration of immune cells. CONCLUSIONS: CFL-1 is highly expressed in HNSCC and is significantly associated with poor prognosis of NHSCC. It is a potential prognostic marker of HNSCC.


Asunto(s)
Cofilina 1 , Neoplasias de Cabeza y Cuello , Carcinoma de Células Escamosas de Cabeza y Cuello , Humanos , Pronóstico , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/mortalidad , Carcinoma de Células Escamosas de Cabeza y Cuello/inmunología , Cofilina 1/genética , Cofilina 1/metabolismo , Neoplasias de Cabeza y Cuello/genética , Neoplasias de Cabeza y Cuello/mortalidad , Neoplasias de Cabeza y Cuello/metabolismo , Tasa de Supervivencia , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Modelos de Riesgos Proporcionales
6.
Materials (Basel) ; 17(14)2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-39063706

RESUMEN

The paper proposes an ultra-wideband frequency selective rasorber (FSR) with low infrared emissivity for the composite detection threat of both radars and infrared sensors. Firstly, the equivalent circuit (EC) method based on transmission line (TL) theory is utilized to analyze the absorption/transmission conditions. Then, based on the analysis above, sinusoidal microstrip lines with non-frequency-varying characteristics are adopted in the design, which significantly enhances the transmission bandwidth of FSR. The FSR demonstrates an absorption band ranging from 2.65 GHz to 8.80 GHz and a transmission band ranging from 9.15 GHz to 17.71 GHz. Furthermore, an infrared shielding layer (IRSL) exhibiting low emissivity in the infrared band and high transmittance in the microwave band is applied to the FSR. The simulation and experiment results verify that the IRSL-FSR demonstrates an ultra-wide transmission band ranging from 9.16 GHz to 17.94 GHz and an ultra-wide absorption band ranging from 2.66 GHz to 8.01 GHz. Additionally, it exhibits a low emissivity value (0.23) in 8-14 µm, providing a viable solution to the formidable challenge of radar-infrared bistealth for satellites and other communication-enabled flying platforms.

7.
Nucleic Acids Res ; 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38966997

RESUMEN

Development of the malaria parasite, Plasmodium falciparum, is regulated by a limited number of sequence-specific transcription factors (TFs). However, the mechanisms by which these TFs recognize genome-wide binding sites is largely unknown. To address TF specificity, we investigated the binding of two TF subsets that either bind CACACA or GTGCAC DNA sequence motifs and further characterized two additional ApiAP2 TFs, PfAP2-G and PfAP2-EXP, which bind unique DNA motifs (GTAC and TGCATGCA). We also interrogated the impact of DNA sequence and chromatin context on P. falciparum TF binding by integrating high-throughput in vitro and in vivo binding assays, DNA shape predictions, epigenetic post-translational modifications, and chromatin accessibility. We found that DNA sequence context minimally impacts binding site selection for paralogous CACACA-binding TFs, while chromatin accessibility, epigenetic patterns, co-factor recruitment, and dimerization correlate with differential binding. In contrast, GTGCAC-binding TFs prefer different DNA sequence context in addition to chromatin dynamics. Finally, we determined that TFs that preferentially bind divergent DNA motifs may bind overlapping genomic regions due to low-affinity binding to other sequence motifs. Our results demonstrate that TF binding site selection relies on a combination of DNA sequence and chromatin features, thereby contributing to the complexity of P. falciparum gene regulatory mechanisms.

8.
Int J Oral Sci ; 16(1): 52, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39085217

RESUMEN

Compared with teenage patients, adult patients generally show a slower rate of tooth movement and more pronounced alveolar bone loss during orthodontic treatment, indicating the maladaptation of alveolar bone homeostasis under orthodontic force. However, this phenomenon is not well-elucidated to date, leading to increased treatment difficulties and unsatisfactory treatment outcomes in adult orthodontics. Aiming to provide a comprehensive knowledge and further inspire insightful understanding towards this issue, this review summarizes the current evidence and underlying mechanisms. The age-related abatements in mechanosensing and mechanotransduction in adult cells and periodontal tissue may contribute to retarded and unbalanced bone metabolism, thus hindering alveolar bone reconstruction during orthodontic treatment. To this end, periodontal surgery, physical and chemical cues are being developed to reactivate or rejuvenate the aging periodontium and restore the dynamic equilibrium of orthodontic-mediated alveolar bone metabolism. We anticipate that this review will present a general overview of the role that aging plays in orthodontic alveolar bone metabolism and shed new light on the prospective ways out of the impasse.


Asunto(s)
Adaptación Fisiológica , Envejecimiento , Pérdida de Hueso Alveolar , Proceso Alveolar , Humanos , Adulto , Envejecimiento/fisiología , Adaptación Fisiológica/fisiología , Técnicas de Movimiento Dental , Mecanotransducción Celular/fisiología , Remodelación Ósea/fisiología
9.
Mol Pharm ; 21(8): 3743-3763, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-38953708

RESUMEN

The coronavirus (COVID-19) pandemic has underscored the critical role of mRNA-based vaccines as powerful, adaptable, readily manufacturable, and safe methodologies for prophylaxis. mRNA-based treatments are emerging as a hopeful avenue for a plethora of conditions, encompassing infectious diseases, cancer, autoimmune diseases, genetic diseases, and rare disorders. Nonetheless, the in vivo delivery of mRNA faces challenges due to its instability, suboptimal delivery, and potential for triggering undesired immune reactions. In this context, the development of effective drug delivery systems, particularly nanoparticles (NPs), is paramount. Tailored with biophysical and chemical properties and susceptible to surface customization, these NPs have demonstrated enhanced mRNA delivery in vivo and led to the approval of several NPs-based formulations for clinical use. Despite these advancements, the necessity for developing a refined, targeted NP delivery system remains imperative. This review comprehensively surveys the biological, translational, and clinical progress in NPs-mediated mRNA therapeutics for both the prevention and treatment of diverse diseases. By addressing critical factors for enhancing existing methodologies, it aims to inform the future development of precise and efficacious mRNA-based therapeutic interventions.


Asunto(s)
COVID-19 , Sistema de Administración de Fármacos con Nanopartículas , ARN Mensajero , Humanos , ARN Mensajero/genética , ARN Mensajero/administración & dosificación , Sistema de Administración de Fármacos con Nanopartículas/química , COVID-19/prevención & control , Nanopartículas/química , Sistemas de Liberación de Medicamentos/métodos , Animales , SARS-CoV-2/efectos de los fármacos , Vacunas de ARNm
10.
Crit Rev Food Sci Nutr ; : 1-15, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38961829

RESUMEN

During the application of Whey proteins (WPs), they often have complex interactions with saccharides (Ss), another important biopolymer in food substrate. The texture and sensory qualities of foods containing WPs and Ss are largely influenced by the interactions of WPs-Ss. Moreover, the combination of WPs and Ss is possible to produce many excellent functional properties including emulsifying properties and thermal stability. However, the interactions between WPs-Ss are complex and susceptible to some processing conditions. In addition, with different interaction ways, they can be applied in different fields. Therefore, the non-covalent interaction mechanisms between WPs-Ss are firstly summarized in detail, including electrostatic interaction, hydrogen bond, hydrophobic interaction, van der Waals force. Furthermore, the existence modes of WPs-Ss are introduced, including complex coacervates, soluble complexes, segregation, and co-solubility. The covalent interactions of WPs-Ss in food applications are often formed by Maillard reaction (dry or wet heat reaction) and occasionally through enzyme induction. Then, two common influencing factors, pH and temperature, on non-covalent/covalent bonds are introduced. Finally, the applications of WPs-Ss complexes and conjugations in improving WP stability, delivery system, and emulsification are described. This review can improve our understanding of the interactions between WPs-Ss and further promote their wider application.

11.
Phys Rev Lett ; 133(2): 023601, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-39073935

RESUMEN

Hong-Ou-Mandel interference is an intrinsic quantum phenomenon that goes beyond the possibilities of classical physics, and enables numerous applications in quantum information science. While the photon-photon interaction is fundamentally limited to the bosonic nature of photons and the restricted phase responses from commonly used unitary optical elements, we present that a nonunitary material provides an alternative degree of freedom to control the two-photon quantum interference, even revealing anomalous quantum interference paths that do not exist in a unitary configuration. An elaborate lossy multilayer graphene that can work as a nonunitary beam splitter is used to explore its tunability over the effective photon-photon interaction in spatial modes, and to verify the particle exchange statistics by its experimental implementation in quantum state filter. This scheme is further extended to observe four-dimensional quantum interference patterns on the lossless and lossy beam splitters, and thus show its applicability even in higher-dimensional Hilbert space.

12.
J Mater Chem B ; 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39082061

RESUMEN

Biological membranes containing transmembrane channels play a crucial role in numerous cellular processes, and mimicking of cell membranes has garnered significant interest in various biomedical applications, particularly nanopore sequencing technology, where remarkable progress has been made with nanopore membranes. Considering the fragility of biomimetic membranes formed by artificial lipids and the limited mimicry of those formed by common block copolymers, this study developed a novel amphiphilic polymer by covalently linking hydrophilic heads of phospholipids to the ends of hydrophobic poly(dimethyl siloxane) (PDMS) chains. The absence of hydrophilic blocks allowed for good control over the polydispersity of this polymer within a narrow range. The high flexibility of PDMS chains, combined with relatively uniform molecular weights, would confer enhanced stability and robustness to polymeric membranes. Dynamic light scattering measurements and microdroplet formation tests demonstrated good amphipathic properties of these novel polymers when maintaining an appropriate hydrophilic-hydrophobic ratio. Moreover, the high similarity between the hydrophilic heads and natural phospholipids makes this polymer more compatible with biomolecules. A successful protein insertion experiment confirmed both the stability of this polymeric membrane and its compatibility with membrane proteins. As a result, this novel amphiphilic polymer exhibits great potential for biomembrane mimicking and paves a new path for material design in biomedical applications.

13.
Cancer Lett ; 595: 217025, 2024 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-38844063

RESUMEN

Despite the confirmed role of LKB1 in suppressing lung cancer progression, its precise effect on cellular senescence is unknown. The aim of this research was to clarify the role and mechanism of LKB1 in restraining telomerase activity in lung adenocarcinoma. The results showed that LKB1 induced cellular senescence and apoptosis either in vitro or in vivo. Overexpression of LKB1 in LKB1-deficient A549 cells led to the inhibition of telomerase activity and the induction of telomere dysfunction by regulating telomerase reverse transcriptase (TERT) expression in terms of transcription. As a transcription factor, Sp1 mediated TERT inhibition after LKB1 overexpression. LKB1 induced lactate production and inhibited histone H4 (Lys8) and H4 (Lys16) lactylation, which further altered Sp1-related transcriptional activity. The telomerase inhibitor BIBR1532 was beneficial for achieving the optimum curative effect of traditional chemotherapeutic drugs accompanied by the glycolysis inhibitor 2DG. These data reveal a new mechanism by which LKB1 regulates telomerase activity through lactylation-dependent transcriptional inhibition, and therefore, provide new insights into the effects of LKB1-mediated senescence in lung adenocarcinoma. Our research has opened up new possibilities for the creation of new cancer treatments.


Asunto(s)
Quinasas de la Proteína-Quinasa Activada por el AMP , Adenocarcinoma del Pulmón , Senescencia Celular , Histonas , Neoplasias Pulmonares , Proteínas Serina-Treonina Quinasas , Factor de Transcripción Sp1 , Telomerasa , Animales , Humanos , Ratones , Células A549 , Adenocarcinoma del Pulmón/patología , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/metabolismo , Adenocarcinoma del Pulmón/tratamiento farmacológico , Quinasas de la Proteína-Quinasa Activada por el AMP/metabolismo , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Senescencia Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica , Histonas/metabolismo , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/tratamiento farmacológico , Ratones Desnudos , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Factor de Transcripción Sp1/metabolismo , Factor de Transcripción Sp1/genética , Telomerasa/metabolismo , Telomerasa/genética , Ensayos Antitumor por Modelo de Xenoinjerto
14.
Front Pharmacol ; 15: 1379166, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38910895

RESUMEN

Maintaining the structural integrity of genomic chromosomal DNA is an essential role of cellular life and requires two important biological mechanisms: the DNA damage response (DDR) mechanism and telomere protection mechanism at chromosome ends. Because abnormalities in telomeres and cellular DDR regulation are strongly associated with human aging and cancer, there is a reciprocal regulation of telomeres and cellular DDR. Moreover, several drug treatments for DDR are currently available. This paper reviews the progress in research on the interaction between telomeres and cellular DNA damage repair pathways. The research on the crosstalk between telomere damage and DDR is important for improving the efficacy of tumor treatment. However, further studies are required to confirm this hypothesis.

15.
Exp Dermatol ; 33(6): e15097, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38840370

RESUMEN

Surgical management of basal cell carcinoma (BCC) typically involves surgical excision with post-operative margin assessment using the bread-loafing technique; or gold-standard Mohs micrographic surgery (MMS), where margins are iteratively examined for residual cancer after tumour removal, with additional excisions performed upon detecting residual tumour at margins. There is limited sampling of resection margins with bread loafing, with detection of positive margins 44% of the time using 2 mm intervals. To resolve this, we have developed three-dimensional (3D) Tissue Imaging for: (1) complete examination of cancer margins and (2) detection of tumour proximity to nerves and blood vessels. 3D Tissue optical clearing with a light sheet imaging protocol was developed for margin assessment in two datasets assessed by two independent evaluators: (1) 48 samples from 29 patients with varied BCC subtypes, sizes and pigmentation levels; (2) 32 samples with matching Mohs' surgeon reading of tumour margins using two-dimensional haematoxylin & eosin-stained sections. The 3D Tissue Imaging protocol permits a complete examination of deeper and peripheral margins. Two independent evaluators achieved negative predictive values of 92.3% and 88.24% with 3D Tissue Imaging. Images obtained from 3D Tissue Imaging recapitulates histological features of BCC, such as nuclear crowding, palisading and retraction clefting and provides a 3D context for recognising normal skin adnexal structures. Concurrent immunofluorescence labelling of nerves and blood vessels allows visualisation of structures closer to tumour-positive regions, which may have a higher risk for neural and vascular infiltration. Together, this method provides more information in a 3D spatial context, enabling better cancer management by clinicians.


Asunto(s)
Carcinoma Basocelular , Imagenología Tridimensional , Márgenes de Escisión , Cirugía de Mohs , Neoplasias Cutáneas , Humanos , Carcinoma Basocelular/diagnóstico por imagen , Carcinoma Basocelular/cirugía , Carcinoma Basocelular/patología , Neoplasias Cutáneas/diagnóstico por imagen , Neoplasias Cutáneas/cirugía , Neoplasias Cutáneas/patología
16.
Ultrason Sonochem ; 108: 106952, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38878714

RESUMEN

The mechanism of generation of shock waves by the collapse of a cavitation bubble near a single particle or dual particles is numerically investigated using OpenFOAM. For the single-particle case, shock waves during bubble inception and jet impacting on the particle surface are revealed in detail. The pressure induced on the particle by the inception shock wave of the bubble decreases with increasing bubble-particle distance, and the pressure is proportional to 1/r1.26 (r being the distance from the center of the shock wave). For the dual particles, the evolution of the neck structure is closely related to the generation mechanism of the shock wave. At extremely close particle-bubble distances, two shock waves propagating in opposite directions are emitted outside and inside the bubble after two necks collide. At long particle-bubble distances, a shock wave is emitted after the neck contracts, and simultaneously the bubble splits into two daughter bubbles. The energy of the shock wave generated by the neck constriction (i.e., the pressure at its generation location) first increases and then decreases with increasing bubble-particle distance. For unequal-sized double particles, the size of the daughter bubble depends on the bubble-particle distance and the particle size. These findings provide new perspectives for understanding the damage sustained by hydro-mechanical components operating in sand-laden water flows.

17.
Adv Mater ; 36(31): e2403659, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38843445

RESUMEN

On-chip integration of 2D materials with unique structures and properties endow integrated devices with new functionalities and improved performance. With high flexibility in ways to modify its properties and compatibility with integrated platforms, graphene oxide (GO) is an exceptionally attractive 2D material for hybrid integrated photonic chips. Here, by harnessing unique property changes induced by photothermal effects in 2D GO films, novel functionalities beyond the capability of photonic integrated circuits are demonstrated. These include all-optical control and tuning, optical power limiting, and nonreciprocal light transmission. The 2D layered GO films are integrated onto photonic chips with precise control of their thickness and size. Benefitting from the broadband optical response of 2D GO films, all three functionalities feature a very wide operational optical bandwidth. By fitting the experimental results with theory, the changes in GO film properties induced by the photothermal effects are analyzed, revealing interesting insights about the physics of 2D GO films. These results highlight the versatility of 2D GO films in implementing new functions for integrated photonic devices for a wide range of applications.

18.
Ultrason Sonochem ; 107: 106942, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38850641

RESUMEN

The jet dynamics of a cavitation bubble near unequal-sized dual particles is investigated employing OpenFOAM, and the effects of the jets on the particles are quantitatively analyzed in terms of their pressure impacts. Different from single-particle cases, the necks that evolve between dual particles are closely linked to the formation mechanism of the jets. Based on the simulation results, the jet dynamics can be divided into five scenarios: (1) the contraction of the annular depression produced by the collision of the two necks causes the bubble to split into two daughter bubbles and generates a single jet inside each daughter bubble; (2) the annular depression impacts the particle, leading to the bubble to fracture and producing a single jet inside a daughter bubble; (3) the bubble is split by a single neck constriction and produces a single jet; (4) the bubble is split by a single neck constriction and generates two jets; and (5) the bubble is split by the contraction of two necks and produces four jets together with three daughter bubbles. As the bubble-particle distance or the radius ratio of the dual particles increases, the maximum force on the small particle generated by the bubble decreases.

19.
Opt Express ; 32(12): 21243-21257, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38859483

RESUMEN

Augmented reality (AR) displays are gaining attention as next-generation intelligent display technologies. Diffractive waveguide technologies are progressively becoming the AR display industry's preferred option. Gradient period polarization volume holographic gratings (PVGs), which are considered to have the potential to expand the field of view (FOV) of waveguide display systems due to their wide bandwidth diffraction characteristics, have been proposed as coupling elements for diffraction waveguide systems in recent years. Here, what we believe to be a novel modeling method for gradient period PVGs is proposed by incorporating grating stacking and scattering analysis utilizing rigorous coupled-wave analysis (RCWA) theory. The diffraction efficiency and polarization response were extensively explored using this simulation model. In addition, a dual-layer full-color diffractive waveguide imaging simulation using proposed gradient period PVGs is accomplished in Zemax software using a self-compiled dynamic link library (DLL), achieving a 53° diagonal FOV at a 16:9 aspect ratio. This work furthers the development of PVGs by providing unique ideas for the field of view design of AR display.

20.
medRxiv ; 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38766134

RESUMEN

Current psychiatric diagnoses are not defined by neurobiological measures which hinders the development of therapies targeting mechanisms underlying mental illness 1,2 . Research confined to diagnostic boundaries yields heterogeneous biological results, whereas transdiagnostic studies often investigate individual symptoms in isolation. There is currently no paradigm available to comprehensively investigate the relationship between different clinical symptoms, individual disorders, and the underlying neurobiological mechanisms. Here, we propose a framework that groups clinical symptoms derived from ICD-10/DSM-V according to shared brain mechanisms defined by brain structure, function, and connectivity. The reassembly of existing ICD-10/DSM-5 symptoms reveal six cross-diagnostic psychopathology scores related to mania symptoms, depressive symptoms, anxiety symptoms, stress symptoms, eating pathology, and fear symptoms. They were consistently associated with multimodal neuroimaging components in the training sample of young adults aged 23, the independent test sample aged 23, participants aged 14 and 19 years, and in psychiatric patients. The identification of symptom groups of mental illness robustly defined by precisely characterized brain mechanisms enables the development of a psychiatric nosology based upon quantifiable neurobiological measures. As the identified symptom groups align well with existing diagnostic categories, our framework is directly applicable to clinical research and patient care.

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