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The skin of Arachis hypogaea L. (peanut or groundnut) is a rich source of polyphenols, which have been shown to exhibit a wider spectrum of noteworthy biological activities, including anticancer effects. However, the anticancer activity of peanut skin extracts against melanoma and colorectal cancer (CRC) cells remains elusive. In this study, we systematically investigated the cytotoxic, antiproliferative, pro-apoptotic, and anti-migration effects of peanut skin ethanolic extract and its fractions on melanoma and CRC cells. Cell viability results showed that the ethyl acetate fraction (AHE) of peanut skin ethanolic crude extract and one of the methanolic fractions (AHE-2) from ethyl acetate extraction exhibited the highest cytotoxicity against melanoma and CRC cells but not in nonmalignant human skin fibroblasts. AHE and AHE-2 effectively modulated the cell cycle-related proteins, including the suppression of cyclin-dependent kinase 4 (CDK4), cyclin-dependent kinase 6 (CDK6), phosphorylation of Retinoblastoma (p-Rb), E2F1, Cyclin A, and activation of tumor suppressor p53, which was associated with cell cycle arrest and paralleled their antiproliferative efficacies. AHE and AHE-2 could also induce caspase-dependent apoptosis and inhibit migration activities in melanoma and CRC cells. Moreover, it is noteworthy that autophagy, manifested by microtubule-associated protein light chain 3B (LC3B) conversion and the aggregation of GFP-LC3, was detected after AHE and AHE-2 treatment and provided protective responses in cancer cells. Significantly, inhibition of autophagy enhanced AHE- and AHE-2-induced cytotoxicity and apoptosis. Together, these findings not only elucidate the anticancer potential of peanut skin extracts against melanoma and CRC cells but also provide a new insight into autophagy implicated in peanut skin extracts-induced cancer cell death.
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Acetatos , Arachis , Melanoma , Humanos , Línea Celular Tumoral , Extractos Vegetales/farmacología , Apoptosis , AutofagiaRESUMEN
Excitation-emission matrix (EEM) spectroscopy has been proven to be an effective tool for offline fluorescence analysis. However, the pretreatment of EEM data requires an additional ultraviolet-visible (UV-vis) absorption spectrum for inner filter effect (IFE) correction. This complicates the instrument structure and increases the test flow, thus hindering the practical application of EEM in environmental online monitoring. In this work, Rayleigh scattering in EEM, which is often masked, is leveraged to address this challenge as Rayleigh scattering light itself passes through the sample and experiences absorption. We establish a translation-corrected estimation by the Rayleigh scattering (TCERS) method to estimate absorbance, not only enabling the IFE self-correction of EEM but also providing orthogonal spectroscopy information. TCERS is hierarchically tested in real solutions, simulated turbid liquids, and various natural water samples. Results indicate that the predicted UV-vis absorption spectra have a cosine similarity of over 0.95 with the actual spectra. When using the predicted spectra to correct the IFE of EEM, only about 0.005/1.440 bits of information entropy are lost and the absolute errors in EEM are negligible. The proposed method has the potential to streamline the design of fluorescence spectrometers, making it possible to miniaturize, optimize, and popularize these instruments for various practical applications such as environmental monitoring.
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Imbibition dynamics in a rectangular U-groove that is connected to a sudden enlargement and complicated by the presence of Concus-Finn (CF) filaments is investigated using many-body dissipative particle dynamics. For open-ended sudden enlargement, four flow types are identified and depend on the contact angle θy, the critical angle θf associated with the occurrence of CF filaments, and the critical angle θc associated with the occurrence of main flow. First, for θy > θf and θy > θc, the corner flow is absent, and the main flow stops at the end of the small U-groove. Second, for θc > θy > θf, the corner flow vanishes, but the main flow occurs. Third, for θf > θy > θc, the corner flow takes place in the large U-groove, but the main flow is still absent. Fourth, for θy < θf and θy < θc, both the corner and main flows appear in the large U-groove. Additionally, the flow dynamics is greatly influenced by the length of the large U-groove (le). For closed-ended sudden enlargement, similar findings can be obtained. However, the outcome of the third case is altered for sufficiently small le, and the sudden enlargement can eventually be filled.
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Antimony (Sb) is a toxic substance that poses a serious ecological threat when released into the environment. The species and redox state of Sb determine its environmental toxicity and fate. Understanding the redox transformations and biogeochemical cycling of Sb is crucial for analyzing and predicting its environmental behavior. Dissolved organic matter (DOM) in the environment greatly affects the fate of Sb. Microbially produced DOM is a vital component of environmental DOM; however, its specific role in Sb(III) oxidation has not been experimentally confirmed. In this work, the oxidation capacity of several Shewanella strains and their derived DOM to Sb(III) was confirmed. The oxidation rate of Sb(III) shows a positive correlation with DOM concentration, with higher rates observed under neutral and weak alkaline conditions, regardless of the presence of light. Incubation experiments indicated that extracellular enzymes and common reactive oxygen species were not involved in the oxidation of Sb(III). Characteristics of DOM suggests that microbial humic acid-like and fulvic acid-like substances are the potential contributors to Sb(III) oxidation. These findings not only experimentally validate the role of bacterial-derived DOM in Sb(III) oxidation but also reveal the significance of Shewanella and biogenic DOM in the biogeochemical cycling of Sb.
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Shewanella , Oxidación-Reducción , Sustancias Húmicas/análisis , Antimonio/química , Materia Orgánica DisueltaRESUMEN
InP-based quantum dot (QD) light-emitting diodes (QLEDs) provide a heavy-metal-free route to size-tuned LEDs having high efficiency. The stability of QLEDs may be enhanced by replacing organic hole-injection layers (HILs) with inorganic layers. However, inorganic HILs reported to date suffer from inefficient hole injection, the result of their shallow work functions. Here, we investigate the tuning of the work function of nickel oxide (NiOx) HILs using self-assembled molecules (SAMs). Density functional theory simulations and near-edge X-ray absorption fine structure put a particular focus onto the molecular orientation of the SAMs in tuning the work function of the NiOx HIL. We find that orientation plays an even stronger role than does the underlying molecular dipole itself: SAMs having the strongest electron-withdrawing nitro group (NO2), despite having a high intrinsic dipole, show limited work function tuning, something we assign to their orientation parallel to the NiOx surface. We further find that the NO2 groupâwhich delocalizes electrons over the molecule by resonanceâinduces a deep lowest unoccupied molecular orbital level that accepts electrons from QDs, producing luminescence quenching. In contrast, SAMs containing a trifluoromethyl group exhibit an angled orientation relative to the NiOx surface, better activating hole injection into the active layer without inducing luminescence quenching. We report an external quantum efficiency (EQE) of 18.8%âthe highest EQE among inorganic HIL-based QLEDs (including Cd-based QDs)âin InP QLEDs employing inorganic HILs.
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Calycosin, a bioactive isoflavonoid isolated from root extracts of Astragalus membranaceus, has been reported to inhibit melanogenesis, the mechanism of which remains undefined. In this study, we interrogated the mechanistic basis by which calycosin inhibits melanin production in two model systems, i.e., B16F10 melanoma cells and zebrafish embryos. Calycosin was effective in protecting B16F10 cells from α-melanocyte-stimulating hormone (α-MSH)-induced melanogenesis and tyrosinase activity. This anti-melanogenic effect was accompanied by decreased expression levels of microphthalmia-associated transcription factor (MITF), a key protein controlling melanin synthesis, and its target genes tyrosinase and tyrosinase-related protein-2 (TRP-2) in calycosin-treated cells. Mechanistically, we obtained the first evidence that calycosin-mediated MITF downregulation was attributable to its ability to block signaling pathways mediated by cAMP response element-binding protein (CREB) and p38 MAP kinase. The protein kinase A (PKA) inhibitor H-89 and p38 inhibitor SB203580 validated the premise that calycosin inhibits melanin synthesis and tyrosinase activity by regulating the PKA/CREB and p38 MAPK signaling pathways. Moreover, the in vivo anti-melanogenic efficacy of calycosin was manifested by its ability to suppress body pigmentation and tyrosinase activity in zebrafish embryos. Together, these data suggested the translational potential of calycosin to be developed as skin-lightening cosmeceuticals.
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Isoflavonas/farmacología , Melaninas/metabolismo , Animales , Astragalus propinquus/metabolismo , Línea Celular Tumoral , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/efectos de los fármacos , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/efectos de los fármacos , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/genética , Expresión Génica/genética , Regulación Neoplásica de la Expresión Génica/genética , Isoflavonas/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/fisiología , Melanoma/tratamiento farmacológico , Melanoma/metabolismo , Factor de Transcripción Asociado a Microftalmía/metabolismo , Fosforilación/efectos de los fármacos , Extractos Vegetales/farmacología , Raíces de Plantas , Transducción de Señal/efectos de los fármacos , Pez Cebra/metabolismo , alfa-MSH/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos/efectos de los fármacos , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
OBJECTIVE: This case-control study investigated the association between statin use and liver injury using Taiwan's National Health Insurance Research Database. METHODS: Our study subjects included 4165 cases (patients who had been admitted with a primary diagnosis of liver injury between 2002 and 2009) and 16 660 age-matched, sex-matched and index date-matched controls. Multivariable conditional regression models were used to estimate the association between statin use and liver injury. RESULTS: Users of statins were not associated with risk of liver injury (adjusted odds ratio [aOR] 1.04; 95% confidence interval [0.90-1.19]) when compared with nonusers. Nevertheless, a higher dose of statin (≥1 defined daily dose; aOR 1.55 [1.14-2.11]) and use of rosuvastatin before event of liver injury (aOR 1.38 [1.03-1.85]) were significantly associated with liver injury. CONCLUSIONS: This population-based study extends previous evidence by exploring the potential association between statins use and risk of liver injury. Overall, we found that statin was not associated with risk of liver injury. Nevertheless, special concern should be paid to those who used statin ≥1 defined daily dose and rosuvastatin.
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Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Fluorobencenos/efectos adversos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Pirimidinas/efectos adversos , Sulfonamidas/efectos adversos , Adulto , Anciano , Estudios de Casos y Controles , Enfermedad Hepática Inducida por Sustancias y Drogas/epidemiología , Bases de Datos Factuales , Relación Dosis-Respuesta a Droga , Femenino , Fluorobencenos/administración & dosificación , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Masculino , Persona de Mediana Edad , Análisis Multivariante , Pirimidinas/administración & dosificación , Análisis de Regresión , Riesgo , Rosuvastatina Cálcica , Sulfonamidas/administración & dosificación , Taiwán , Adulto JovenRESUMEN
Highly realistic imaging and video synthesis have become possible and relatively simple tasks with the rapid growth of generative adversarial networks (GANs). GAN-related applications, such as DeepFake image and video manipulation and adversarial attacks, have been used to disrupt and confound the truth in images and videos over social media. DeepFake technology aims to synthesize high visual quality image content that can mislead the human vision system, while the adversarial perturbation attempts to mislead the deep neural networks to a wrong prediction. Defense strategy becomes difficult when adversarial perturbation and DeepFake are combined. This study examined a novel deceptive mechanism based on statistical hypothesis testing against DeepFake manipulation and adversarial attacks. First, a deceptive model based on two isolated sub-networks was designed to generate two-dimensional random variables with a specific distribution for detecting the DeepFake image and video. This research proposes a maximum likelihood loss for training the deceptive model with two isolated sub-networks. Afterward, a novel hypothesis was proposed for a testing scheme to detect the DeepFake video and images with a well-trained deceptive model. The comprehensive experiments demonstrated that the proposed decoy mechanism could be generalized to compressed and unseen manipulation methods for both DeepFake and attack detection.
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Algoritmos , Redes Neurales de la Computación , HumanosRESUMEN
The limited information on microbial interactions and metabolic patterns in denitrification systems, especially those fed with different carbon sources, has hindered the establishment of ecological linkages between microscale connections and macroscopic reactor performance. In this work, denitrification performance, metabolic patterns, and ecological structure were investigated in parallel well-controlled bioreactors with four representative carbon sources, i.e., methanol, glycerol, acetate, and glucose. After long-term acclimation, significant differences were observed among the four bioreactors in terms of denitrification rates, organic utilization, and heterotrophic bacterial yields. Different carbon sources induced the succession of denitrifying microbiota toward different ecological structures and exhibited distinct metabolic patterns. Methanol-fed reactors showed distinctive microbial carbon utilization pathways and a more intricate microbial interaction network, leading to significant variations in organic utilization and metabolite production compared to other carbon sources. Three keystone taxa belonging to the Verrucomicrobiota phylum, SJA-15 order and the Kineosphaera genus appeared as network hubs in the methanol, glycerol, and acetate-fed systems, playing essential roles in their ecological functions. Several highly connected species were also identified within the glucose-fed system. The close relationship between microbial metabolites, ecological structures, and system performances suggests that this complex network relationship may greatly contribute to the efficient operation of bioreactors.
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Carbono , Desnitrificación , Carbono/química , Metanol , Glicerol , Reactores Biológicos/microbiología , Acetatos , Glucosa , Nitrógeno/metabolismo , Nitratos/metabolismoRESUMEN
The exploring of molecular-level heterogeneity of dissolved organic matter (DOM) in highly connected water bodies is of great importance for pollution tracing and lake management, and provides new perspectives on the transformations and fate of DOM in aquatic systems. However, the inherent homogeneity of DOM in connected water bodies poses challenges for its heterogeneity analysis. In this work, an innovative method combining fluorescence spectroscopy, high-resolution mass spectrometry (HRMS), and cluster analysis was developed to reveal the heterogeneity of DOM in highly connected water bodies at the molecular level. We detected 4538 molecules across 36 sampling sites in Chaohu Lake using HRMS. Cluster analysis based on excitation-emission matrix (EEM) data effectively divided the sampling sites into four clusters, representing the water bodies from West Chaohu Lake, East Chaohu Lake, agricultural land, and urban areas. Analysis of DOM in the western and eastern parts of the lake revealed that aerobic degradation led to a decrease in CHOS and aliphatic compounds, alongside an increase in CHO and highly unsaturated and phenolic compounds. Furthermore, we unveiled the characteristics and sources of heterogeneity in DOM from agricultural land and urban areas. Our method accurately captured the heterogeneous distribution of DOM in the lake and revealed the heterogeneous composition of DOM at molecular level. This work underscores the importance of integrating complementary spectroscopic analyses with HRMS in DOM research with similar compositions.
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Materia Orgánica Disuelta , Sustancias Húmicas , Espectrometría de Masas , Sustancias Húmicas/análisis , Agricultura , Espectrometría de Fluorescencia , Lagos/química , Agua/análisisRESUMEN
As a result of the trend toward economic globalization, the vigorous development of cross-border e-commerce has attracted many scholars to study this field, involving many related fields, such as consumer behavior, advertising, information systems, and supply chain management. Throughout the existing literature, it can be found that most of the research focuses on certain influencing factors of the development of cross-border e-commerce, and there is no systematic and macro- overview of the development trend of research in this field in recent years, nor the integration and analysis of keywords. Given that the research in the field of cross-border e-commerce is fragmented to a large extent, to effectively explore the research trend in this field, we must understand the current situation of cross-border e-commerce. Systematic bibliometric analysis can solve this problem by providing publishing trends and information on various topics. Therefore, based on the scientific database web, this study collected 198 references related to cross-border e-commerce from 2016 to 2021, briefly introduced the current situation and development trend of cross-border e-commerce, visually analyzed and refined the journals, authors, research institutions, countries, publication years, keywords, citations of academic publications in this field, and other key information, and summarized the development trend and path of CEBC in the existing research. It is helpful for researchers to solve the current research gap, understand the future research direction in this field, and help academia establish a strict knowledge system.
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Over the past decade, neuroscience has been integrated into information systems as a new methodology and perspective to study and solve related problems. Therefore, NeuroIS has emerged as a new cutting-edge research field. This review aimed to identify, summarize, and classify existing NeuroIS publications through knowledge mapping and bibliometric analysis. To effectively understand the development trend of NeuroIS, this study referred to the journal selection index of the Association of Business Schools in 2021 and journals above three stars in the field of information management as the main selection basis. A total of 99 neuroscience papers and their citation data were included from 19 major information systems journals of SCI/SSCI. This study analyzed bibliometric data from 2010 to 2021 to identify the most productive countries, universities, authors, journals, and prolific publications in NeuroIS. To this end, VOSviewer was used to visualize mapping based on co-citation, bibliographic coupling, and co-occurrence. Keywords with strong citation bursts were also identified in this study. This signifies the evolution of this research field and may reveal potential research directions in the near future. In selecting research methods and analysis tools for NeuroIS, content analysis was used to further conclude and summarize the relevant trends. Moreover, a co-citation network analysis was conducted to help understand how the papers, journals, and authors in the field were connected and related, and to identify the seminal or pioneering major literature. For researchers, network maps visualized mainstream research and provided a structural understanding of NeuroIS. The review concludes by discussing potential research topics in this field.
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BACKGROUND: It is unclear about the impact of recreational drug use on the adherence, drug-drug interaction and the occurrence of sexual transmitted diseases (STDs) among people living with HIV. MATERIAL AND METHODS: A retrospective study was conducted between Dec 2016, and July 2018 to assess the clinical impact of recreational drug consumption in people living with HIV with antiretroviral therapy. We collected data of the demographics, recreational drug use, laboratory results and STDs diagnoses. Potential drug-drug interactions were checked with reference databases. The association between recreational drug use and STDs, HIV viral load suppression and drug interactions were evaluated. RESULTS: A total of 462 participants were enrolled, included 384 recreational drug users and 78 non-recreational drug users. Younger age (adjusted odds ratio [aOR], 0.94; 95% CI: 0.91-0.98; p = 0.001), longer HIV infection period (aOR, 1.11; 95% CI: 1.03-1.20; p = 0.009) and poor antiretroviral drug adherence (1-2 pills missing per month: aOR, 6.82; 95% CI: 3.50-13.27; p < 0.001; >2 pills missing per month: aOR, 3.50; 95% CI: 1.28-9.61; p = 0.015) were factors associated with recreational drug use. Methamphetamine and nitrites were two most common recreational drugs. Recreational drug use was significantly associated with STDs in one-year follow-up period (aOR, 2.43; 95% CI: 1.11-5.32; p = 0.027) but was not significantly associated with unsuppressed viral load, though a trend was observed (OR, 2.23; 95% CI: 0.92-5.37; p = 0.074). Potential interactions with recreational drugs included 33.1% antiretroviral drugs and 31.3% medications for comorbidities. CONCLUSION: Recreational drug was associated with STDs. A great proportion of the patients consuming recreational drugs had potential interactions with antiretroviral drugs and medications for comorbidities. The association of recreational drug use and unsuppressed viral load warrants further investigation.
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Infecciones por VIH/epidemiología , Uso Recreativo de Drogas/estadística & datos numéricos , Adulto , Antirretrovirales/uso terapéutico , Terapia Antirretroviral Altamente Activa , Interacciones Farmacológicas , Femenino , Infecciones por VIH/tratamiento farmacológico , Humanos , Masculino , Cumplimiento de la Medicación/estadística & datos numéricos , Persona de Mediana Edad , Estudios Retrospectivos , Enfermedades de Transmisión Sexual/epidemiología , Taiwán/epidemiología , Carga Viral/efectos de los fármacosRESUMEN
Our previous study explored the dual effect of lipoic acid on the regulation of IL-6 expression in C2C12 myotubes. However, the specific mechanism remains unclear. To evaluate IL-6 signaling in skeletal muscle, pCMV6-IL-6 was overexpressed in C2C12 myotubes. The real-time quantitative polymerase chain reaction was used to detect mRNA expression. Immunohistochemistry and a DeadEnd colorimetric TUNEL system were used to detect IL-6 localization and analyze the apoptosis in IL-6-overexpressing cells, respectively. A caspase-3/CPP32 colorimetric assay and Western blotting were used to analyze caspase-3 activity and protein expression, respectively. Our results showed the overexpressed IL-6 was not only located in the cytosol but also on the intracellular side of the cell membrane. Moreover, the nucleus did not demonstrate IL-6 overexpression. The DeadEnd colorimetric apoptosis detection assay results demonstrated that apoptotic nuclei were present in IL-6-overexpressing cells. However, the overexpressed IL-6 failed to promote caspase-3 activity. Notably, the exogenous pyrogen lipopolysaccharide (LPS) significantly promoted IL-6 mRNA expression and caspase-3 activity but did not induce apoptotic cell formation. Moreover, lipoic acid significantly upregulated IL-6, IL-6Ra, and gp130 mRNA expression and significantly increased caspase-3 activity but did not induce apoptotic cell formation. Lipoic acid significantly increased the p-Akt level in untreated cells but not in LY294002-treated cells. Taken together, our results suggesting that the overexpressed IL-6-induced apoptosis may not be mediated by caspase-3. LPS-induced IL-6 mRNA expression may not be involved in IL-6 classical signaling or trans-signaling in C2C12 myotubes. Lipoic acid-induced IL-6 mRNA expression may be mediated by IL-6 classical signaling in C2C12 myotubes. [Figure: see text].
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Interleucina-6/metabolismo , Lipopolisacáridos/farmacología , Fibras Musculares Esqueléticas/efectos de los fármacos , Ácido Tióctico/farmacología , Animales , Apoptosis/efectos de los fármacos , Línea Celular , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Citosol/efectos de los fármacos , Citosol/metabolismo , Interleucina-6/análisis , Interleucina-6/genética , Ratones , Fibras Musculares Esqueléticas/metabolismo , ARN Mensajero/análisis , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transducción de Señal/efectos de los fármacosRESUMEN
The sonogram is currently an effective cancer screening and diagnosis way due to the convenience and harmlessness in humans. Traditionally, lesion boundary segmentation is first adopted and then classification is conducted, to reach the judgment of benign or malignant tumor. In addition, sonograms often contain much speckle noise and intensity inhomogeneity. This study proposes a novel benign or malignant tumor classification system, which comprises intensity inhomogeneity correction and stacked denoising autoencoder (SDAE), and it is suitable for small-size dataset. A classifier is established by extracting features in the multilayer training of SDAE; automatic analysis of imaging features by the deep learning algorithm is applied on image classification, thus allowing the system to have high efficiency and robust distinguishing. In this study, two kinds of dataset (private data and public data) are used for deep learning models training. For each dataset, two groups of test images are compared: the original images and the images after intensity inhomogeneity correction, respectively. The results show that when deep learning algorithm is applied on the sonograms after intensity inhomogeneity correction, there is a significant increase of the tumor distinguishing accuracy. This study demonstrated that it is important to use preprocessing to highlight the image features and further give these features for deep learning models. In this way, the classification accuracy will be better to just use the original images for deep learning.
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Neoplasias de la Mama/diagnóstico por imagen , Aprendizaje Profundo , Interpretación de Imagen Asistida por Computador/métodos , Ultrasonografía Mamaria/métodos , Algoritmos , Mama/diagnóstico por imagen , Femenino , HumanosRESUMEN
In this research, the Zn(C5H7O2)2·xH2O-based growth of ZnO micro/nanostructures in a low temperature, vapor-trapped chemical vapor deposition system was attempted to optimize structural and optical properties for potential biomedical applications. By trapping in-flow gas molecules and Zinc vapor inside a chamber tube by partially obstructing a chamber outlet, a high pressure condition can be achieved, and this experimental setup has the advantages of ease of synthesis, being a low temperature process, and cost effectiveness. Empirically, the growth process proceeded under a chamber condition of an atmospheric pressure of 730 torr, a controlled volume flow rate of input gas, N2/O2, of 500/500 Standard Cubic Centimeters per Minute (SCCM), and a designated oven temperature of 500 °C. Specifically, the dependence of structural and optical properties of the structures on growth duration and spatially dependent temperature were investigated utilizing scanning electron microscopy, X-ray diffraction (XRD), photoluminescence (PL), and ultraviolet-visible transmission spectroscopy. The experimental results indicate that the grown thin film observed with hexagonal structures and higher structural uniformity enables more prominent structural and optical signatures. XRD spectra present the dominant peaks along crystal planes of (002) and (101) as the main direction of crystallization. In addition, while the structures excited with laser wavelength of 325 nm emit a signature radiation around 380 nm, an ultraviolet lamp with a wavelength of 254 nm revealed distinctive photoluminescence peaks at 363.96 nm and 403.52 nm, elucidating different degrees of structural correlation as functions of growth duration and the spatial gradient of temperature. Transmittance spectra of the structures illustrate typical variation in the wavelength range of 200 nm to 400 nm, and its structural correlation is less significant when compared with PL.
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Hydrothermal vent organisms have evolved physiological adaptations to cope with extreme abiotic conditions including temperature and pH. To date, acid-base regulatory abilities of vent organisms are poorly investigated, although this physiological feature is essential for survival in low pH environments. We report the acid-base regulatory mechanisms of a hydrothermal vent crab, Xenograpsus testudinatus, endemic to highly acidic shallow-water vent habitats with average environment pH-values ranging between 5.4 and 6.6. Within a few hours, X. testudinatus restores extracellular pH (pHe) in response to environmental acidification of pH 6.5 (1.78 kPa pCO2) accompanied by an increase in blood [Formula: see text] levels from 8.8 ± 0.3 to 31 ± 6 mM. Branchial Na(+)/K(+)-ATPase (NKA) and V-type H(+)-ATPase (VHA), the major ion pumps involved in branchial acid-base regulation, showed dynamic increases in response to acidified conditions on the mRNA, protein and activity level. Immunohistochemical analyses demonstrate the presence of NKA in basolateral membranes, whereas the VHA is predominantly localized in cytoplasmic vesicles of branchial epithelial- and pillar-cells. X. testudinatus is closely related to other strong osmo-regulating brachyurans, which is also reflected in the phylogeny of the NKA. Accordingly, our results suggest that the evolution of strong ion regulatory abilities in brachyuran crabs that allowed the occupation of ecological niches in euryhaline, freshwater, and terrestrial habitats are probably also linked to substantial acid-base regulatory abilities. This physiological trait allowed X. testudinatus to successfully inhabit one of the world's most acidic marine environments.
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Conductive ink using copper nanoparticles has attracted much attention in the printed electronics industry because of its low cost and high electrical conductivity. However, the problem of easy oxidation under heat and humidity conditions for copper material limits the wide applications. In this study, antioxidative copper inks were prepared by dispersing the nanoparticles in the solution, and then conductive copper films can be obtained after calcining the copper ink at 250 °C in nitrogen atmosphere for 30 min. A low sheet resistance of 47.6 mΩ/â¡ for the copper film was measured by using the four-point probe method. Importantly, we experimentally demonstrate that the electrical conductivity of copper films can be improved by increasing the calcination temperature. In addition, these highly conductive copper films can be placed in an atmospheric environment for more than 6 months without the oxidation phenomenon, which was verified by energy-dispersive X-ray spectroscopy (EDS). These observations strongly show that our conductive copper ink features high antioxidant properties and long-term stability and has a great potential for many printed electronics applications, such as flexible display systems, sensors, photovoltaic cells, and radio frequency identification.