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1.
J Acoust Soc Am ; 153(1): 505, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36732252

RESUMO

Type IV flextensional transducers do not have broadband characteristics due to the deep valley between their first- and second-order response curves arising from the sound pressure cancellation produced by the vibration in different areas of the shell. In this paper, the cause of the deep valley is examined by analyzing the equivalent radiated sound field of the transducer. Simplifying the three-dimensional vibration equation to a two-dimensional equation shows that the vibration state of the shell is related to the positive and negative curvature. Therefore, a variable-shell flextensional transducer with a negative curvature is proposed, which changes the second-order vibration of the transducer by introducing a negative curvature structure. The transducer avoids acoustic pressure cancellation, achieves broadband characteristics, and has continuous high efficiency in the frequency band. After optimization, a prototype of the transducer is fabricated and a pool test is completed. The test results show that the transducer realizes the coupling of the first three vibration mode, forming a broad band with an in-band fluctuation of less than 8 dB at 1200-5600 Hz, and the efficiencies of the first to third resonance peaks are 30.2 %, 16.6 %, and 9.4 %, respectively.

3.
J Affect Disord ; 325: 119-126, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36621674

RESUMO

BACKGROUND: This study aimed to investigate (1) the mental health impacts (i.e., insomnia and suicide ideas) of the COVID-19 pandemic and (2) the mediation effects of stay-at-home levels on those impacts. METHODS: This study investigated monthly national COVID-19 deaths, stay-at-home levels, and internet searches for words for "insomnia" and "suicide" across 45 countries during the first year of the COVID-19 pandemic (March 1, 2020, to February 28, 2021). We used the changes of internet search volumes for "insomnia" and "suicide" (from the Google Trends database) to represent the mental health impacts, and the time of cell phone activity at the residence (from Google Location History) to estimate the stay-at-home effects. We computed the proportion mediated (PM) caused by stay-at-home levels in the COVID-19 impacts on insomnia and suicide ideas, respectively. RESULTS: Throughout the first year of the COVID-19 pandemic, national COVID-19 deaths significantly correlated to increased internet searches for "insomnia" but decreased searches for "suicide". In addition, the mediation effect was significant in the first six-month of COVID-19-related increases in insomnia (PM = 42.6 %, p = 0.016), but this effect was not significant (PM = 13.1 %, p = 0.270) in the second six-month. By contrast, the mediation effect was not significant in the first six-month of COVID-19-related decrease in suicide ideation (PM = 8.1 %, p = 0.180), but this effect was significant (PM = 39.6 %, p = 0.014) in the second six-month. CONCLUSIONS: Stay-at-home levels significantly mediated both increased insomnia and decreased suicide ideas, but within different time frames.

4.
Int J Psychol ; 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36720650

RESUMO

Objective structured clinical examinations (OSCEs) have been widely used in health care education to simultaneously assess knowledge, skill and attitude. Due to the high cost of running an OSCE, its application in professional psychology is still limited. To solve this problem, virtual standardised patient (VSP) implementations in creating psychology OSCEs can be a cost-effective method for administering a psychology OSCE regularly. This study aimed to develop and examine the psychometric properties of the VSP version of the Intake OSCE (VSP-Intake OSCE) in measuring psychologists' psychological assessment competencies (PACs) from entry to early practice. The initial development of the VSP-Intake OSCE contains a VSP station and a follow-up written station to measure PACs when conducting an intake assessment. To administer the VSP station, we built a new VSP system that allows psychologists to interact with a VSP verbally. A sample of 36 participants, including 27 graduate students and nine psychologists, were recruited to examine the psychometric properties of the VSP-Intake OSCE. As a newly developed instrument, the VSP-Intake OSCE revealed good inter-rater reliability and construct validity. We believe using VSP implementations to develop psychology OSCEs will be essential in promoting OSCE applications in professional psychology.

5.
Int J Biol Macromol ; 229: 1054-1068, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36627036

RESUMO

The crucial need for quality refined sugar has led to the development of advanced adsorbents, with a focus on the decolorization of remelt syrup. In this study, (3-chloro-2-hydroxypropyl) trimethylammonium chloride and polyethyleneimine co-modified pomelo peel cellulose-derived aerogel (CP-PPA) was fabricated, and synthetic melanoidins were used as model colorants of remelt syrup to evaluate the validity and practicality of CP-PPA for eliminating colored impurities. Integrating abundant amine-functionalized groups (quaternary ammonium and protonated amine) within the pomelo peel-derived aerogel directionally captured electronegative melanoidins via electrostatic interactions. Furthermore, the active sites, types, and relative strength of the weak interactions between CP-PPA and melanoidins were determined using density functional theory simulations. CP-PPA exhibited an excellent equilibration adsorbing capacity for capturing melanoidins of 749.51 mg/g, and a removal efficiency of 93.69 %. Additionally, the adsorption mechanism was thoroughly examined in an effort to improve the economy of the sugar refinement industry.


Assuntos
Cloretos , Açúcares , Polietilenoimina , Celulose , Derivados da Hipromelose , Aminas , Adsorção
6.
Cereb Cortex ; 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36627244

RESUMO

Duchenne muscular dystrophy (DMD) is frequently associated with mild cognitive deficits. However, the underlying disrupted brain connectome and the neural basis remain unclear. In our current study, 38 first-episode, treatment-naive patients with DMD and 22 matched healthy controls (HC) were enrolled and received resting-sate functional magnetic resonance imaging scans. Voxel-based degree centrality (DC), seed-based functional connectivity (FC), and clinical correlation were performed. Relative to HC, DMD patients had lower height, full Intellectual Quotients (IQ), and IQ-verbal comprehension. Significant increment of DC of DMD patients were found in the left dorsolateral prefrontal cortex (DLPFC.L) and right dorsomedial prefrontal cortex (DMPFC.R), while decreased DC were found in right cerebellum posterior lobe (CPL.R), right precentral/postcentral gyrus (Pre/Postcentral G.R). DMD patients had stronger FC in CPL.R-bilateral lingual gyrus, Pre/Postcentral G.R-Insular, and DMPFC.R-Precuneus.R, had attenuated FC in DLPFC.L-Insular. These abnormally functional couplings were closely associated with the extent of cognitive impairment, suggested an over-activation of default mode network and executive control network, and a suppression of primary sensorimotor cortex and cerebellum-visual circuit. The findings collectively suggest the distributed brain connectome disturbances maybe a neuroimaging biomarker in DMD patients with mild cognitive impairment.

7.
Adv Sci (Weinh) ; : e2203813, 2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36638254

RESUMO

In the aorta of mid-gestational mouse embryos, a specialized endothelial subpopulation termed hemogenic endothelial cells (HECs) develops into hematopoietic stem and progenitor cells (HSPCs), through a conserved process of endothelial-to-hematopoietic transition (EHT). EHT is tightly controlled by multiple intrinsic and extrinsic mechanisms. Nevertheless, the molecular regulators restraining this process remain poorly understood. Here, it is uncovered that, one of the previously identified HEC signature genes, Nupr1, negatively regulates the EHT process. Nupr1 deletion in endothelial cells results in increased HSPC generation in the aorta-gonad-mesonephros region. Furthermore, single-cell transcriptomics combined with serial functional assays reveals that loss of Nupr1 promotes the EHT process by promoting the specification of hematopoiesis-primed functional HECs and strengthening their subsequent hematopoietic differentiation potential toward HSPCs. This study further finds that the proinflammatory cytokine, tumor necrosis factor α (TNF-α), is significantly upregulated in Nupr1-deficient HECs, and the use of a specific TNF-α neutralizing antibody partially reduces excessive HSPC generation in the explant cultures from Nupr1-deficient embryos. This study identifies a novel negative regulator of EHT and the findings indicate that Nupr1 is a new potential target for future hematopoietic stem cell regeneration research.

8.
Nat Chem ; 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36646894

RESUMO

Over the past decades, many efficient methodologies have been developed that allow for the enantioselective synthesis of chiral sulfinyl compounds. However, the enantioselective deoxygenation of hexavalent sulfones for the formation of chiral sulfinyl compounds still remains one of the major challenges in the fields of asymmetric synthesis and organosulfur chemistry. Here we have demonstrated that a synergistic combination of organocatalysis and the incorporation of a cyano group into the sulfone generates a chiral sulfinic species as an active intermediate. A wide range of chiral sulfinates with high enantioselectivities could then be acquired using alcohols as nucleophiles, and the subsequent transformations allowed the collective preparation of a variety of chiral sulfinyl compounds. Density functional theory calculations revealed that the catalytic cycle involves a quinuclidine-assisted stepwise 1,2-cyano group transfer, base-assisted intermolecular substitution with alcohol and regeneration of the active catalyst. The enantioselectivity was determined by the cyano migration step.

10.
Sci Adv ; 9(4): eade2981, 2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36706176

RESUMO

Late-stage skeletal reorganization (LSSR) is a type of fascinating organic transformation processes in natural product total synthesis. However, few facile and effective LSSR methodologies have hitherto been developed. Here, LSSR of limonoid natural products via photochemical cascades is first reported. Starting from xyloelves A and B, nine distinct limonoid products with five unprecedented scaffolds are generated. The photocascade pathways of these natural products and mechanistic rationale via intramolecular triplet energy transfer are revealed by quantum mechanical calculations. Most notably, ultraviolet light-driven transannular and stereoselective C â†’ C 1,4-acyl migration is first found as a photochemical approach, particularly for LSSR of natural products. This approach holds promise for designing LSSR strategies to access bioactive cage-like molecules. Besides that, our findings provide a clear proof of concept for natural product photobiosynthesis. Xyloelf A, substantially ameliorating concanavalin A-induced liver injury in mice, could be used as a unique molecular template for hepatoprotective drug discovery.


Assuntos
Produtos Biológicos , Limoninas , Animais , Camundongos , Raios Ultravioleta , Limoninas/farmacologia , Descoberta de Drogas , Produtos Biológicos/química
11.
Spat Spatiotemporal Epidemiol ; 44: 100563, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36707196

RESUMO

BACKGROUND: Public health organizations have increasingly harnessed geospatial technologies for disease surveillance, health services allocation, and targeting place-based health promotion initiatives. METHODS: We conducted a systematic review around the theme of space-time clustering detection techniques for infectious diseases using PubMed, Web of Science, and Scopus. Two reviewers independently determined inclusion and exclusion. RESULTS: Of 2,887 articles identified, 354 studies met inclusion criteria, the majority of which were application papers. Studies of airborne diseases were dominant, followed by vector-borne diseases. Most research used aggregated data instead of point data, and a significant proportion of articles used a repetition of a spatial clustering method, instead of using a "true" space-time detection approach, potentially leading to the detection of false positives. Noticeably, most articles did not make their data available, limiting replicability. CONCLUSION: This review underlines recent trends in the application of space-time clustering methods to the field of infectious disease, with a rapid increase during the COVID-19 pandemic.


Assuntos
COVID-19 , Doenças Transmissíveis , Humanos , COVID-19/epidemiologia , Pandemias , Doenças Transmissíveis/diagnóstico , Doenças Transmissíveis/epidemiologia , Análise Espacial , Saúde Pública
12.
Nat Commun ; 14(1): 470, 2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36709324

RESUMO

Pathology diagnostics relies on the assessment of morphology by trained experts, which remains subjective and qualitative. Here we developed a framework for large-scale histomorphometry (FLASH) performing deep learning-based semantic segmentation and subsequent large-scale extraction of interpretable, quantitative, morphometric features in non-tumour kidney histology. We use two internal and three external, multi-centre cohorts to analyse over 1000 kidney biopsies and nephrectomies. By associating morphometric features with clinical parameters, we confirm previous concepts and reveal unexpected relations. We show that the extracted features are independent predictors of long-term clinical outcomes in IgA-nephropathy. We introduce single-structure morphometric analysis by applying techniques from single-cell transcriptomics, identifying distinct glomerular populations and morphometric phenotypes along a trajectory of disease progression. Our study provides a concept for Next-generation Morphometry (NGM), enabling comprehensive quantitative pathology data mining, i.e., pathomics.


Assuntos
Glomérulos Renais , Rim , Rim/patologia , Glomérulos Renais/patologia
13.
J Am Chem Soc ; 145(4): 2207-2218, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36689704

RESUMO

Reductive elimination is a key step in Ni-catalyzed cross-couplings. Compared with processes that proceed from Ni(III) or Ni(IV) intermediates, C(sp3)-C(sp3) reductive eliminations from Ni(II) centers are challenging due to the weak oxidizing ability of Ni(II) species. In this report, we present computational evidence that supports a mechanism in which Zn coordination to the nickel center as a Z-type ligand accelerates reductive elimination. This Zn-assisted pathway is found to be lower in energy compared with direct reductive elimination from a σ-coordinated Ni(II) intermediate, providing new insights into the mechanism of Ni-catalyzed cross-coupling with organozinc nucleophiles. Mayer bond order, Hirshfield charge, Laplacian of the electron density, orbital, and interaction region indicator analyses were conducted to elucidate details of the reductive elimination process and characterize the key intermediates. Theoretical calculations indicate a significant Z-type Ni-Zn interaction that reduces the electron density around the Ni center and accelerates reductive elimination. This mechanistic study of reductive elimination in Ni(0)-catalyzed conjunctive cross-couplings of aryl iodides, organozinc reagents, and alkenes is an important case study of the involvement of Zn-assisted reductive elimination in Ni catalysis. We anticipate that the novel Zn-assisted reductive elimination mode may extend to other cross-coupling processes and explain the unique effectiveness of organozinc nucleophiles in many instances.

14.
Sci Rep ; 13(1): 53, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36593245

RESUMO

Selenium is an essential micronutrient element. For the extremely biotoxic of selenite, Selenium nanoparticles (SeNPs) is gaining increasing interest. In this work, a selenium-enriched strain with highly selenite-resistant (up to 173 mmol/L) was isolated from the local specialty food of longevity area and identified as Paenibacillus motobuensis (P. motobuensis) LY5201. Most of the SeNPs were accumulated extracellular. SeNPs were around spherical with a diameter of approximately 100 nm. The X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy showed that the purified SeNPs consisted of selenium and proteins. Our results suggested that P. motobuensis LY5201could be a suitable and robust biocatalyst for SeNPs synthesis. In addition, the cytotoxicity effect and the anti-invasive activity of SeNPs on the HepG2 showed an inhibitory effect on HepG2, indicating that SeNPs could be used as a potential anticancer drug.


Assuntos
Antineoplásicos , Nanopartículas , Selênio , Selênio/metabolismo , Nanopartículas/química , Antineoplásicos/farmacologia , Ácido Selenioso/metabolismo
15.
Colloids Surf B Biointerfaces ; 222: 113086, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36542953

RESUMO

The host-material interface is critical in determining the successful integration of medical devices into human tissue. The surface topography can regulate the fibrous capsule formation around implants through macrophage polarization, but the exact mechanism remains unclear. In this study, four types of microgrooves (10 or 50 µm in groove depths and 50 or 200 µm in groove widths) were fabricated on polydimethylsiloxane (PDMS) using lithography. The microgroove surfaces were characterized using the laser scanning confocal microscopy and fourier transform infrared spectroscopy. The effect of surface topography on macrophage phenotypes and conditioned medium (CM) collected from macrophages on human foreskin fibroblast 1 (HFF-1) were investigated. The result revealed that a deeper and narrower microgroove structure means a rougher surface. Macrophages tended to adhere and aggregate on group 50-50 surface (groove depths and widths of 50 µm). THP-1 cell polarized toward both inflammatory M1 and anti-inflammatory M2 macrophages on the surface of each group. Meanwhile, CM from macrophages culture on PDMS differentially up-regulated the proliferation, migration and fibrosis of HFF-1. Among them, the group 50-50 had the strongest promoting effect. In vivo, the inflammatory response and fibrotic capsule around the implants were observed at 1 week and 4 weeks. As time passed, the inflammatory response decreased, while the capsule thickness continued to increase. The rough material surface was more inclined to develop a severe fibrotic encapsulation. In conclusion, this finding further suggested a potential immunomodulatory effect of macrophages in mediating the fibrotic response to implants and facilitated the design of biomaterial interfaces for improving tissue integration.

16.
Mol Med Rep ; 27(2)2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36524366

RESUMO

Although arsenic is an environmental toxicant, arsenic trioxide (ATO) is used to treat acute promyelocytic leukemia (APL) with anticancer effects. Studies have demonstrated oral cancer is in the top 10 cancers in Taiwan. High rate of oral cancers is linked to various behaviors, such as excessive alcohol consumption and tobacco use. Similarly, betel chewing is a strong risk factor in oral cancer. In the present study, oral squamous carcinoma OC3 cells were investigated with the treatments of sodium arsenite (NaAsO2) and dimethylarsenic acid (DMA), respectively, to examine if arsenic compounds have anti­cancer efforts. It was found that 1 µM NaAsO2 and 1 mM DMA for 24 h induced rounded contours with membrane blebbing phenomena in OC3 cells, revealing cell apoptotic characteristics. In addition, NaAsO2 (10­100 µM) and DMA (1­100 mM) significantly decreased OC3 cell survival. In cell cycle regulation detected by flow cytometry, NaAsO2 and DMA significantly augmented percentage of subG1 and G2/M phases in OC3 cells, respectively. Annexin V/PI double staining assay was further used to confirm NaAsO2 and DMA did induce OC3 cell apoptosis. In mechanism investigation, western blotting assay was applied and the results showed that NaAsO2 and DMA significantly induced phosphorylation of JNK, ERK1/2 and p38 and then the cleavages of caspase­8, ­9, ­3 and poly ADP­ribose polymerase (PARP) in OC3 cells, dynamically. In conclusion, NaAsO2 and DMA activated MAPK pathways and then apoptotic pathways to induce OC3 oral cancer cell apoptosis.


Assuntos
Arsenicais , Neoplasias Bucais , Humanos , Ácido Cacodílico/farmacologia , Linhagem Celular Tumoral , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/patologia , Apoptose , Arsenicais/farmacologia
17.
Asian J Psychiatr ; 79: 103393, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36521405

RESUMO

BACKGROUND: The transformation from institutionalization to community-based mental healthcare may increase the difficulty of psychiatric workforce estimation and change the role of psychiatrists in hospitals and private clinics. METHODS: This study aimed to estimate the growth and forecast psychiatric services in hospitals and private clinics in Taiwan from 2005 to 2030. We first examined the correlation between the number of psychiatrists and several indicators of psychiatric services. The forecast of the national demand for psychiatrists was based on projected outpatient psychiatrist visits from historical data. We also estimated the supply of psychiatrists by the number of psychiatrists practicing in hospitals or private clinics from Taiwan's Medical Affairs System and examined the supply and demand of the psychiatrist workforce through 2030. RESULTS: Outpatient visit was the most relevant indicator of psychiatric services to psychiatrist workforce. Growth rates in private clinics were higher than the hospital counterparts within the following decade (172.3 % vs. 37.7 %) and in the following decade (42.3 % vs. 13.3 %). The hospital-clinic disparity in the growth of psychiatric services also reflects the shortage of psychiatrists in private clinics but not in hospitals through 2030. The supply of 1158 psychiatrists in hospitals would nearly equal the clinical-based demand of 1156 psychiatrists in 2030. By contrast, the supply of 514 psychiatrists in private clinics would be lower than the clinical-based demand of 636 psychiatrists in 2030. CONCLUSION: The hospital-clinic disparity in the growth of psychiatric services reflects the transformation from hospital-based to community-based mental healthcare in Taiwan.


Assuntos
Serviços de Saúde Mental , Psiquiatria , Humanos , Taiwan , Recursos Humanos , Pacientes Ambulatoriais
19.
ACS Omega ; 7(47): 43273-43282, 2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36467912

RESUMO

Polyimide/boron nitride nanosheet (PI/BNNS) composite films have potential applications in the field of electrical devices due to the superior thermal conductivity and outstanding insulating properties of the boron nitride nanosheet. In this study, the boron nitride nanosheet (BNNS-t) was prepared by the template method using sodium chloride as the template, and B2O3 and flowing ammonia as the boron and nitrogen sources, respectively. Then, the PI/BNNS-t composite films were investigated with different loading of BNNS-t as thermally conductive fillers. The results show that BNNS-t has a high aspect ratio and a uniform lateral dimension, with a large dimension and a thin thickness, and there are a few nanosheets with angular shapes in the as-obtained BNNS-t. The synergistic effect of the above characteristics for BNNS-t is beneficial to constructing the three-dimensional heat conduction network of the PI/BNNS-t composite films, which can significantly improve the out-of-plane thermal conduction properties. And then, the out-of-plane thermal conductivity of the PI/BNNS-t composite film achieves 0.67 W m-1 K-1 at 40% loading, which is nearly 3.5 times that of the PI film.

20.
Langmuir ; 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36454955

RESUMO

Nanodiscs are broadly used for characterization of membrane proteins as they are generally assumed to provide a near-native environment. In fact, it is an open question whether the physical properties of lipids in nanodiscs and membrane vesicles of the same lipid composition are identical. Here, we investigate the properties of lipids (1,2-dipalmitoyl-sn-glycero-3-phosphocholine, 1,2-dilauroyl-sn-glycero-3-phosphocholine, and their mixtures) in two different sample types, nanodiscs and multilamellar vesicles, by means of spin-label electron spin resonance techniques. Our results provide a quantitative description of lipid dynamics and ordering, elucidating the molecular details of how lipids in the two sample types behave differently in response to temperature and lipid composition. We show that the properties of lipids are altered in nanodiscs such that the dissimilarity of the fluid and gel lipid phases is reduced, and the first-order phase transitions are largely abolished in nanodiscs. We unveil that the ensemble of lipids in the middle of a nanodisc bilayer, as probed by the end-chain spin-label 16-PC, is promoted to a state close to a miscibility critical point, thereby rendering the phase transitions continuous. Critical phenomena have recently been proposed to explain features of the heterogeneity in native cell membranes. Our results lay the groundwork for how to establish a near-native environment in nanodiscs with simple organization of lipid components.

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