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1.
Small ; : e2309891, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38721972

RESUMO

Although the current cancer photothermal therapy (PTT) can produce a powerful therapeutic effect, tumor cells have been proved a protective mechanism through autophagy. In this study, a novel hybrid theranostic nanoparticle (CaCO3@CQ@pDB NPs, CCD NPs) is designed and prepared by integrating a second near-infrared (NIR-II) absorbed conjugated polymer DTP-BBT (pDB), CaCO3, and autophagy inhibitor (chloroquine, CQ) into one nanosystem. The conjugated polymer pDB with asymmetric donor-acceptor structure shows strong NIR-II absorbing capacity, of which the optical properties and photothermal generation mechanism of pDB are systematically analyzed via molecular theoretical calculation. Under NIR-II laser irradiation, pDB-mediated PTT can produce powerful killing ability to tumor cells. At the same time, heat stimulates a large amount of Ca2+ inflow, causing calcium overload induced mitochondrial damage and enhancing the apoptosis of tumor cells. Besides, the released CQ blocks the self-protection mechanism of tumor cells and greatly enhances the attack of PTT and calcium overload therapy. Both in vitro and in vivo experiments confirm that CCD NPs possess excellent NIR-II theranostic capacity, which provides a new nanoplatform for anti-tumor therapy and builds great potential for future clinical research.

2.
Environ Sci Technol ; 58(19): 8432-8443, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38699990

RESUMO

Sea salt (ss) aerosols in PM2.5 are often quantified through source apportionment by applying sodium (Na+) and chloride (Cl-) as the markers, but both markers can be substantially emitted from anthropogenic sources. In this study, we differentiate ss from nonss (nss) portions of Na+ and Cl- to better apportion PM2.5 in a coastal tropical urban environment. Size-resolved ionic profiles accounting for Cl- depletion of aged ss were applied to 162-day measurements during 2012 and 2018-2019. Results show that the nss (likely anthropogenic) portions, on average, account for 50-80% of total Na+ and Cl- in submicron aerosols (PM1). This corresponds to up to 2.5 µg/m3 of ss in submicron aerosols that can be ∼10 times overestimated if one attributes all Na+ and Cl- in PM1 to ss. Employing the newly speciated ss- and nss-portions of Na+ and Cl- to source apportionment of urban PM2.5 via positive matrix factorization uncovers a new source of transported anthropogenic emissions during the southwest monsoon, contributing to 12-15% of PM2.5. This increases anthropogenic PM2.5 by ≥19% and reduces ss-related PM2.5 by >30%. In addition to demonstrating Cl- depletion (aging) in submicron aerosols and quantifying ssNa+, nssNa+, ssCl-, as well as nssCl- therein, the refined PM2.5 apportionment resolves new insights on PM2.5 of anthropogenic origins in urban environments, useful to facilitate policy making.


Assuntos
Aerossóis , Poluentes Atmosféricos , Cidades , Monitoramento Ambiental , Material Particulado , Monitoramento Ambiental/métodos , Poluentes Atmosféricos/análise
3.
Nano Lett ; 22(11): 4325-4332, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35579622

RESUMO

Thermal properties of materials are often determined by measuring thermalization processes; however, such measurements at the nanoscale are challenging because they require high sensitivity concurrently with high temporal and spatial resolutions. Here, we develop an optomechanical cantilever probe and customize an atomic force microscope with low detection noise ≈1 fm/Hz1/2 over a wide (>100 MHz) bandwidth that measures thermalization dynamics with ≈10 ns temporal resolution, ≈35 nm spatial resolution, and high sensitivity. This setup enables fast nanoimaging of thermal conductivity (η) and interfacial thermal conductance (G) with measurement throughputs ≈6000× faster than conventional macroscale-resolution time-domain thermoreflectance acquiring the full sample thermalization. As a proof-of-principle demonstration, 100 × 100 pixel maps of η and G of a polymer particle are obtained in 200 s with a small relative uncertainty (<10%). This work paves the way to study fast thermal dynamics in materials and devices at the nanoscale.

4.
Acta Biochim Biophys Sin (Shanghai) ; 54(11): 1708-1719, 2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36017889

RESUMO

Adenocarcinoma is the second largest histological type of cervical cancer, second only to cervical squamous cell carcinoma. At present, despite the clinical treatment strategies of cervical adenocarcinoma and cervical squamous cell carcinoma being similar, the outcome and prognosis of cervical adenocarcinoma are significantly poor. Therefore, it is urgent to find specific biomarker and therapeutic target for cervical adenocarcinoma. In this study, we aim to reveal and verify the potential biomarkers and therapeutic targets of cervical adenocarcinoma. Weighted correlation network analysis (WGCNA) reveals the differentially-expressed genes significantly related to the histological characteristics of the two cervical cancer subtypes. We select the genes with the top 20 significance for further investigation. Through microarray and immunohistochemical (IHC) analyses of a variety of tumor tissues, we find that among these 20 genes, AHNAK2 is highly expressed not only in cervical adenocarcinoma, but also in multiple of adenocarcinoma tissues, including esophagus, breast and colon, while not in normal gland tissues. In vitro, AHNAK2 knockdown significantly inhibits cell proliferation and migration of adenocarcinoma cell lines. In vivo, AHNAK2 knockdown significantly inhibits tumor progression and metastasis of various adenocarcinomas. RNA-sequencing and bioinformatics analyses suggest that the inhibitory effect of AHNAK2 knockdown on tumor progression is achieved by regulating DNA replication and upregulating Bim expression. Together, we demonstrate that AHNAK2 is a biomarker and a potential therapeutic target for adenocarcinomas.


Assuntos
Adenocarcinoma , Biomarcadores Tumorais , Carcinoma de Células Escamosas , Terapia de Alvo Molecular , Neoplasias do Colo do Útero , Feminino , Humanos , Adenocarcinoma/tratamento farmacológico , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia
5.
J Mammary Gland Biol Neoplasia ; 26(3): 309-320, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34374886

RESUMO

Mammary gland development primarily occurs postnatally, and this unique process is complex and regulated by systemic hormones and local growth factors. The mammary gland is also a highly dynamic organ that undergoes profound changes at puberty and during the reproductive cycle. These changes are driven by mammary stem cells (MaSCs). Breast cancer is one of the most common causes of cancer-related death in women. Cancer stem cells (CSCs) play prominent roles in tumor initiation, drug resistance, tumor recurrence, and metastasis. The highly conserved Notch signaling pathway functions as a key regulator of the niche mediating mammary organogenesis and breast neoplasia. In this review, we discuss mechanisms by which Notch contributes to breast carcinoma pathology and suggest potentials for therapeutic targeting of Notch in breast cancer. In summary, we provide a comprehensive overview of Notch functions in regulating MaSCs, mammary development, and breast cancer.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Carcinogênese/metabolismo , Glândulas Mamárias Humanas/crescimento & desenvolvimento , Glândulas Mamárias Humanas/metabolismo , Receptores Notch/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/fisiopatologia , Carcinogênese/patologia , Feminino , Humanos , Glândulas Mamárias Humanas/patologia , Transdução de Sinais , Células-Tronco/metabolismo , Células-Tronco/patologia
6.
BMC Public Health ; 21(1): 1608, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34470632

RESUMO

BACKGROUND AND AIM: According to the United Nations' Sustainable Development Goal (SDG) target 3.4, premature mortality from four non-communicable diseases (cardiovascular diseases, cancer, chronic respiratory diseases, and diabetes mellitus, collectively referred to as NCD4) should achieve a minimum decline of 33% in 2030 relative to 2015. This remains a challenge for China. This study aimed to evaluate the current status and progress towards this target in Liaoning Province, one of the three provinces in northeast China. METHODS: We calculated the premature mortality rates (PMRs) per year and average annual percentage changes (AAPCs) from NCD4 using mortality data between 2004 and 2017. The trend was analyzed in the whole population, as well as in subpopulations of gender (male/female) and inhabiting area (urban/rural). PMRs from NCD4 for 2030 were projected by fitting a linear regression based on the current trend, which was identified by a Joinpoint model. FINDINGS: In the whole population, only chronic respiratory diseases showed a significant decline (AAPC: - 6.5%, p < 0.05), while only cancer showed a significant increase (AAPC: + 1.3%, p < 0.05); taken together, NCD4 showed a significant increase (AAPC: + 0.6%, p < 0.05). In the subpopulations, while males showed a significant increase in NCD4 (AAPC: + 1.5%, p < 0.05), cardiovascular diseases (AAPC: + 1.7%, p < 0.05), cancer (AAPC: + 1.8%, p < 0.05), and diabetes mellitus (AAPC: + 4.2%, p < 0.05), females showed a significant decline in NCD4 (AAPC: - 1.2%, p < 0.05), cardiovascular diseases (AAPC: - 1.8%, p < 0.05), diabetes mellitus (AAPC: - 2.1%, p < 0.05), but showed a mild increase in cancer (AAPC: + 0.5%, p > 0.05). A comparative analysis of the projected PMRs for 2030 with the 2015 levels revealed that only chronic respiratory diseases are expected to achieve the SDG target 3.4, apart from in the urban male subpopulation. CONCLUSION: Except for chronic respiratory diseases, NCD4 cannot be expected to achieve the SDG target 3.4 in the whole population of Liaoning Province. Under these circumstances, special attention should be paid to reducing the risks of cancer and providing preventative interventions for men.


Assuntos
Doenças não Transmissíveis , Desenvolvimento Sustentável , China/epidemiologia , Feminino , Objetivos , Humanos , Masculino , Mortalidade Prematura , Doenças não Transmissíveis/epidemiologia
7.
Proc Natl Acad Sci U S A ; 115(49): 12419-12424, 2018 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-30455288

RESUMO

In response to a strong El Niño, fires in Indonesia during September and October 2015 released a large amount of carbon dioxide and created a massive regional smoke cloud that severely degraded air quality in many urban centers across Southeast Asia. Although several lines of evidence indicate that peat burning was a dominant contributor to emissions in the region, El Niño-induced drought is also known to increase deforestation fires and agricultural waste burning in plantations. As a result, uncertainties remain with respect to partitioning emissions among different ecosystem and fire types. Here we measured the radiocarbon content (14C) of carbonaceous aerosol samples collected in Singapore from September 2014 through October 2015, with the aim of identifying the age and origin of fire-emitted fine particulate matter (particulate matter with an aerodynamic diameter less than or equal to 2.5 µm). The Δ14C of fire-emitted aerosol was -76 ± 51‰, corresponding to a carbon pool of combusted organic matter with a mean turnover time of 800 ± 420 y. Our observations indicated that smoke plumes reaching Singapore originated primarily from peat burning (∼85%), and not from deforestation fires or waste burning. Atmospheric transport modeling confirmed that fires in Sumatra and Borneo were dominant contributors to elevated PM2.5 in Singapore during the fire season. The mean age of the carbonaceous aerosol, which predates the Industrial Revolution, highlights the importance of improving peatland fire management during future El Niño events for meeting climate mitigation and air quality commitments.

8.
Ecotoxicol Environ Saf ; 208: 111702, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396033

RESUMO

Cellular models exhibiting human physiological features of pseudostratified columnar epithelia, provide a more realistic approach for elucidating detailed mechanisms underlying PM2.5-induced pulmonary toxicity. In this study, we characterized the barrier and mucociliary functions of differentiated human small airway epithelial cells (SAECs), cultured at the air-liquid interface (ALI). Due to the presence of mucociliary protection, particle internalization was reduced, with a concomitant decrease in cytotoxicity in differentiated S-ALI cells, as compared to conventional submerged SAEC cultures. After 24-hour exposure to PM2.5 surrogates, 117 up-regulated genes and 156 down-regulated genes were detected in S-ALI cells, through transcriptomic analysis using the Affymetrix Clariom™ S Human Array. Transcription-level changes in >60 signaling pathways, were revealed by functional annotation of the 273 differentially expressed genes, using the PANTHER Gene List Analysis. These pathways are involved in multiple cellular processes, that include inflammation and apoptosis. Exposure to urban PM2.5 led to complex responses in airway epithelia, including a net induction of downstream pro-inflammatory and pro-apoptotic responses. Collectively, this study highlights the importance of using the more advanced ALI model rather than the undifferentiated submerged model, to avoid over-assessment of inhaled particle toxicity in human. The results of our study also suggest that reduction of ambient PM2.5 concentrations would have a protective effect on respiratory health in humans.


Assuntos
Poluentes Atmosféricos/toxicidade , Células Epiteliais/efeitos dos fármacos , Material Particulado/toxicidade , Transcriptoma/efeitos dos fármacos , Poluentes Atmosféricos/química , Apoptose/efeitos dos fármacos , Células Cultivadas , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Perfilação da Expressão Gênica , Humanos , Tamanho da Partícula , Material Particulado/química , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
9.
Aesthetic Plast Surg ; 45(5): 2417-2422, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34075462

RESUMO

OBJECTIVE: The present study aimed to explore the efficacy and safety profile of liquid phase concentrated growth factor (LPCGF) in promoting autologous fat graft survival. METHODS: LPCGF/PRP was mixed with human fat tissues at different proportions and transplanted into nude mice. Three months after transplantation, the implanted fat tissues were retrieved for analysis. H&E staining was used to quantify the neovascularization. Immunohistochemical staining was applied to quantify the CD34-positive stem cells and the fluorescence intensity of VEGF and TGF-ß. RESULTS: Addition of LPCGF to autologous fat reduced the fat absorption by 5-15%, especially at the early stage, and no complications were observed. In addition, the effect was improved with increased CGF. Liquid phase concentrated growth factor improves autologous fat graft survival, and the most suitable ratio of LPCGF/fat is 1:8. CONCLUSION: LPCGF is rich in VEGF, TGF-ß and CD34-positive stem cells, which can improve the fat transplantation effect, but the specific influence of a single component requires future evaluation. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Tecido Adiposo , Sobrevivência de Enxerto , Animais , Peptídeos e Proteínas de Sinalização Intercelular , Camundongos , Camundongos Nus , Transplante Autólogo
10.
BMC Psychiatry ; 20(1): 151, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-32252706

RESUMO

BACKGROUND: The high heterosexual marriage rate could be a 'double-edge' sword for the emotional health of Chinese men who have sex with men (MSM). The aim of this study was to determine if current marriage and breakdown of marriage (divorce) have different effects on the mental health of Chinese MSM. METHODS: Eight hundred seven MSM were recruited using respondent-driven sampling from four cities in northeastern China. Gay-related stressful events (GRSE) were measured using the Gay Related Stressful Life Events Scale; social support was measured by the Social Support Rating Scale (SSRS); and depressive and anxiety symptoms were assessed using the Self-Rating Depression Scale (SDS) and Self-Rating Anxiety Scale (SAS), respectively. RESULTS: Of the study participants, 13.4% were married to women and 4.5% were divorced. The rates of marriage or divorce were 35.3 and 75.8% for participants 30-39 and > 40 years of age, respectively. The current married MSM had the highest SDS (50.0 ± 10.9) and SSRS (35.8 ± 8.6) levels, but the lowest SAS (38.7 ± 12.1) levels. Divorced MSM had the highest SAS (44.4 ± 9.6) and lowest SSRS (30.8 ± 8.1) levels. Age, GESE number, and HIV infection were predictors for SDS and SAS, and current marriage was associated with significantly decreased level of SAS (ß = - 0.136, P = 0.001) based on multiple linear analysis. CONCLUSIONS: Current marriage is associated with significantly decreased levels of anxiety symptoms among Chinese MSM. More studies are needed to understand the mechanisms underlying the effects of different marriage status on the emotional distress of Chinese MSM.


Assuntos
Ansiedade/psicologia , Homossexualidade Masculina/psicologia , Casamento/psicologia , Apoio Social , Adolescente , Adulto , Ansiedade/etnologia , China , Feminino , Infecções por HIV , Heterossexualidade , Humanos , Masculino , Comportamento Sexual , Minorias Sexuais e de Gênero , Adulto Jovem
11.
Ecotoxicol Environ Saf ; 202: 110932, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800216

RESUMO

Adverse health effects arising from exposure to fine particulates have become a major concern. Angiogenesis is a vital physiological process for the growth and development of cells and structures in the human body, whereby excessive or insufficient vessel growth could contribute to pathogenesis of diseases. We therefore evaluated indirect effects of carbon black (CB) and inhalable airborne particles on the angiogenic ability of unexposed Human Umbilical Vein Endothelial Cells (HUVECs) by co-culturing HUVECs with pre-exposed Small Airway Epithelial Cells (SAECs). As endothelial cells are major components of blood vessels and potential targets of fine particles, we investigated if lung epithelial cells exposed to ambient PM2.5 surrogates could induce bystander effects on neighboring unexposed endothelial cells in an alveolar-capillary co-culture lung model. Epithelial exposure to CB at a non-toxic dose of 25 µg/mL reduced endothelial tube formation and cell adhesion in co-cultured HUVECs, and decreased expression of angiogenic genes in SAECs. Similarly, exposure of differentiated SAECs to PM2.5 surrogates reduced cell reproductive ability, adhesion and tube formation of neighboring HUVECs. This indicates epithelial exposure to CB and urban PM2.5 surrogates both compromised the angiogenic ability of endothelial cells through bystander effects, thereby potentially perturbing the ventilation-perfusion ratio and affecting lung function.


Assuntos
Poluentes Atmosféricos/toxicidade , Material Particulado/toxicidade , Testes de Toxicidade , Técnicas de Cocultura , Células Epiteliais , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Pulmão/metabolismo , Neovascularização Patológica , Fuligem
12.
Entropy (Basel) ; 20(2)2018 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33265195

RESUMO

Many text mining tasks such as text retrieval, text summarization, and text comparisons depend on the extraction of representative keywords from the main text. Most existing keyword extraction algorithms are based on discrete bag-of-words type of word representation of the text. In this paper, we propose a patent keyword extraction algorithm (PKEA) based on the distributed Skip-gram model for patent classification. We also develop a set of quantitative performance measures for keyword extraction evaluation based on information gain and cross-validation, based on Support Vector Machine (SVM) classification, which are valuable when human-annotated keywords are not available. We used a standard benchmark dataset and a homemade patent dataset to evaluate the performance of PKEA. Our patent dataset includes 2500 patents from five distinct technological fields related to autonomous cars (GPS systems, lidar systems, object recognition systems, radar systems, and vehicle control systems). We compared our method with Frequency, Term Frequency-Inverse Document Frequency (TF-IDF), TextRank and Rapid Automatic Keyword Extraction (RAKE). The experimental results show that our proposed algorithm provides a promising way to extract keywords from patent texts for patent classification.

13.
Environ Sci Technol ; 51(17): 10041-10049, 2017 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-28753306

RESUMO

Severe air pollution has become a global concern, and there is a pressing need to develop effective and efficient air filters for removing airborne particulate matters (PMs). In this work, a highly permeable poly(ether sulfone) (PES) based hollow fiber membrane was developed via a one-step dry-jet wet spinning. For the first time, a hollow fiber membrane was used in removing the ultrafine particles (PMs with aerodynamic equivalent diameters of less than 100 nm) in PM2.5. The novel air filter was designed to possess the synergistic advantages of porous filters and fibrous filters with a sievelike outer surface and a fibrouslike porous substrate. A filtration efficiency of higher than 99.995% could be easily achieved when the self-support hollow fiber was challenged with less than 300 nm particulates. Without losses of the structural advantages, we have demonstrated that the permeation properties of the hollow fiber membrane can be facilely tailored via manipulation of the dope and bore fluid formulations. Various cleaning strategies were explored to regenerate the membrane performance after fouling. Both water rinse and backwash showed effectiveness to restore the membrane permeance for repetitive usage.


Assuntos
Poluição do Ar , Filtração , Filtros de Ar , Material Particulado , Sulfonas
14.
Opt Express ; 24(9): 9224-36, 2016 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-27137539

RESUMO

We perform a comprehensive theoretical assessment of fabrication tolerances for a 2D eight-level binary phase grating that is the central element of a multi-focal plane 3D microscopy apparatus. The fabrication process encompasses a sequence of aligned lithography and etching steps with stringent requirements on layer-to-layer overlay, etch depth and etched sidewall slope, which we show are nonetheless achievable with state-of-the-art optical lithography and etching tools. We also perform broadband spectroscopic diffraction pattern measurements on a fabricated grating, and show how such measurements can be valuable in determining small fabrication errors in diffractive optical elements.

15.
BMC Psychiatry ; 16: 117, 2016 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-27129468

RESUMO

BACKGROUND: To describe the level and risk factors for suicidal behaviors in Chinese men who have sex with men (MSM). METHODS: A total of 807 MSM were recruited using a respondent-driven sampling method from Anshan, Benxi, Dandong, and Shenyang cities in northeastern China. RESULTS: Chinese MSM had lifetime prevalences of suicide ideation (18.3%), plan (8.7%) and attempt (4.6%) that were about 2.8, 5.8 and 5.8 times greater than that of male adults in the general population of China. The MSM with any psychiatric disorders were 4-7 times more likely to think about, plan or attempt suicide than those MSM with no disorder, and there was a clear relationship between the number of comorbid disorders and suicidal behaviors. Multiple regression analysis showed that major depression, bipolar disorder, dysthymia and alcohol use disorder significantly increased the risk for suicide ideation, but not for suicide attempt. Drug dependence disorder, panic disorder and generalized anxiety disorder significantly increased the risk for suicide attempt, but not for suicide ideation. More advanced education reduced the risk of suicidal behaviors, sexual orientations revealed to or discovered by family members or friends significantly increased risk of these suicidal behaviors. CONCLUSIONS: Chinese MSM have significantly increased risk for suicidal behaviors, mental disorders and their comorbidities could be the largest risk factors for the elevated suicidal behaviors in Chinese MSM. Reducing the family and social stigma and rejection of homosexual behavior and early detection and effective treatment of psychiatric disorders and their comorbidities in MSM may help to decrease suicidal behaviors of Chinese MSM.


Assuntos
Transtorno Depressivo Maior/epidemiologia , Homossexualidade Masculina/estatística & dados numéricos , Ideação Suicida , Adolescente , Adulto , Transtorno Bipolar/epidemiologia , China/epidemiologia , Comorbidade , Transtorno Depressivo Maior/psicologia , Homossexualidade Masculina/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Comportamento Sexual , Tentativa de Suicídio/psicologia , Inquéritos e Questionários
16.
J Res Natl Inst Stand Technol ; 121: 464-475, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-34434635

RESUMO

This article introduces in archival form the Nanolithography Toolbox, a platform-independent software package for scripted lithography pattern layout generation. The Center for Nanoscale Science and Technology (CNST) at the National Institute of Standards and Technology (NIST) developed the Nanolithography Toolbox to help users of the CNST NanoFab design devices with complex curves and aggressive critical dimensions. Using parameterized shapes as building blocks, the Nanolithography Toolbox allows users to rapidly design and layout nanoscale devices of arbitrary complexity through scripting and programming. The Toolbox offers many parameterized shapes, including structure libraries for micro- and nanoelectromechanical systems (MEMS and NEMS) and nanophotonic devices. Furthermore, the Toolbox allows users to precisely define the number of vertices for each shape or create vectorized shapes using Bezier curves. Parameterized control allows users to design smooth curves with complex shapes. The Toolbox is applicable to a broad range of design tasks in the fabrication of microscale and nanoscale devices.

17.
PLoS One ; 19(3): e0298230, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38451921

RESUMO

To address the issue of poor performance in the chimp optimization (ChOA) algorithm, a new algorithm called the manta ray-based chimpa optimization algorithm (MChOA) was developed. Introducing the Latin hypercube method to construct the initial population so that the individuals of the initial population are evenly distributed in the solution space, increasing the diversity of the initial population. Introducing nonlinear convergence factors based on positive cut functions to changing the convergence of algorithms, the early survey capabilities and later development capabilities of the algorithm are balanced. The manta ray foraging strategy is introduced at the position update to make up for the defect that the algorithm is prone to local optimization, which effectively improves the optimization performance of the algorithm. To evaluate the performance of the proposed algorithm, 27 well-known test reference functions were selected for experimentation, which showed significant advantages compared to other algorithms. Finally, in order to further verify the algorithm's applicability in actual production processes, it was applied to solve scheduling problems in three flexible workshop scenarios and an aviation engine job shop scheduling in an enterprise. This confirmed its efficacy in addressing complex real-world problems.


Assuntos
Aviação , Elasmobrânquios , Humanos , Animais , Algoritmos , Pesquisa Empírica , Pan troglodytes
19.
Sci Total Environ ; 941: 173145, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38768732

RESUMO

The COVID-19 pandemic has given a chance for researchers and policymakers all over the world to study the impact of lockdowns on air quality in each country. This review aims to investigate the impact of the restriction of activities during the lockdowns in the Asian Monsoon region on the main criteria air pollutants. The various types of lockdowns implemented in each country were based on the severity of the COVID-19 pandemic. The concentrations of major air pollutants, especially particulate matter (PM) and nitrogen dioxide (NO2), reduced significantly in all countries, especially in South Asia (India and Bangladesh), during periods of full lockdown. There were also indications of a significant reduction of sulfur dioxide (SO2) and carbon monoxide (CO). At the same time, there were indications of increasing trends in surface ozone (O3), presumably due to nonlinear chemistry associated with the reduction of oxides of nitrogens (NOX). The reduction in the concentration of air pollutants can also be seen in satellite images. The results of aerosol optical depth (AOD) values followed the PM concentrations in many cities. A significant reduction of NO2 was recorded by satellite images in almost all cities in the Asian Monsoon region. The major reductions in air pollutants were associated with reductions in mobility. Pakistan, Bangladesh, Myanmar, Vietnam, and Taiwan had comparatively positive gross domestic product growth indices in comparison to other Asian Monsoon nations during the COVID-19 pandemic. A positive outcome suggests that the economy of these nations, particularly in terms of industrial activity, persisted during the COVID-19 pandemic. Overall, the lockdowns implemented during COVID-19 suggest that air quality in the Asian Monsoon region can be improved by the reduction of emissions, especially those due to mobility as an indicator of traffic in major cities.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Material Particulado , COVID-19/epidemiologia , Poluição do Ar/estatística & dados numéricos , Poluentes Atmosféricos/análise , Material Particulado/análise , Monitoramento Ambiental , Ásia/epidemiologia , Dióxido de Nitrogênio/análise , Humanos , Ozônio/análise , Pandemias , Dióxido de Enxofre/análise , SARS-CoV-2 , Bangladesh/epidemiologia , Índia/epidemiologia
20.
J Nanosci Nanotechnol ; 13(7): 4981-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23901520

RESUMO

Phosphorus-doped (P-doped) TiO2 catalysts with a stable anatase-brookite biphase structure were successfully synthesized by integrating ultrasonication with phosphorus doping and Pluronic P123 surfactant. The synthesized catalysts were characterized using X-ray diffraction, transmission electron microscopy, nitrogen adsorption-desorption, Fourier transform infrared, and UV-visible diffuse reflectance spectra. Ultrasonication facilitates the appearance of brookite phase. Phosphorus doping was demonstrated an effective strategy to stabilize the anatase-brookite biphase structure and inhibits undesirable grain growth. Triblock copolymer Pluronic P123 used in the reaction facilitates the formation of catalyst particles with mesoporous structure and large surface area and prevents particles from agglomeration. The low band-gap of brookite phase enables the synthesized P-doped TiO2 catalysts outperform commercial P25 TiO2 and N-doped TiO2 in the degradation of methylene blue under both solar light and visible light irradiation.


Assuntos
Nanoestruturas/química , Nanoestruturas/ultraestrutura , Fósforo/química , Titânio/química , Catálise , Luz , Teste de Materiais , Nanoestruturas/efeitos da radiação , Tamanho da Partícula , Transição de Fase , Fósforo/efeitos da radiação , Titânio/efeitos da radiação
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