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Hydroxyl radical (â¢OH) with strong oxidation capability is one of the most important reactive oxygen species. The generation of â¢OH from superoxide radicals (â¢O2 -) is an important process in visible-light-driven photocatalysis, but the conversion generally suffers from slow reaction kinetics. Here, a hydrophobicity promoted efficient â¢OH generation in a visible-light-driven semiconductor-mediated photodegradation reaction is reported. Hydrophobic TiO2 that is synthesized by modifying the TiO2 surface with a thin polydimethylsiloxane (PDMS) layer and rhodamine B (RhB) are used as model semiconductors and dye molecules, respectively. The surface hydrophobicity resulted in the formation of a solid-liquid-air triphase interface microenvironment, which increased the local concentration of O2. In the meanwhile, the saturated adsorption quantity of RhB on hydrophobic TiO2 is improved by five-fold than that on untreated TiO2. These advantages increased the density of the conduction band photoelectrons and â¢O2 - generation, and stimulated the conversion of â¢O2 - to â¢OH. This consequently not only increased the kinetics of the photocatalytic reaction by an order of magnitude, but also altered the oxidation route from conventional decolorization to mineralization. This study highlights the importance of surface wettability modulation in boosting â¢OH generation in visible-light-driven photocatalysis.
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BACKGROUND: Sarcopenia can lead to a series of unfavourable health outcomes. Diet is an important factor influencing sarcopenia. In this study, we aimed to evaluate the association of sarcopenia with diet quality assessed by the Chinese Diet Balance Index 2016 (DBI-16). METHODS: A cross-sectional study was conducted to collect information on nutrition and health in Henan Province, China, and a total of 644 individuals were studied. Sarcopenia was defined according to the Asian Working Group for Sarcopenia (AWGS) criteria updated in 2019. Diet quality was assessed by using the Chinese Diet Balance Index 2016 (DBI-16), which includes three indicators: the lower bound score (LBS), higher bound score (HBS) and diet quality distance (DQD). Binary logistic regression analysis was used to estimate the risk of sarcopenia associated with diet quality. RESULTS: A total of 49 of the 644 participants were diagnosed with sarcopenia. Excessive intake (score > 0) of cereals, meat, eggs and salt, inadequate intake (score < 0) of vegetables, fruits, dairy products, soybeans and low diet variety were commonly seen in both groups of participants. The participants with sarcopenia had a more serious inadequate intake of fruit than those without sarcopenia (p < 0.05). The overall LBS, HBS and DQD in both groups were in the interval of low-level problems. Compared with participants with a suitable LBS, those with an unsuitable LBS were more likely to have a low gait speed (OR: 2.58; 95%CI: 1.13-7.04) after multiple adjustments. However, the other two DBI-16 indicators, the HBS and DQD, were not associated with sarcopenia or its related diagnostic variables. CONCLUSION: Unfavourable diet quality, mainly referring to inadequate dietary intake in this study, may be a risk factor for low gait speed.
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População do Leste Asiático , Sarcopenia , Humanos , Adulto , Estudos Transversais , Sarcopenia/epidemiologia , Dieta , Verduras , China/epidemiologiaRESUMO
BACKGROUND: Recent studies have confirmed that combined surgery and anti-TNF therapy could improve outcomes in patients with perianal fistulising Crohn's disease (PFCD). However, the optimal timing for infliximab infusion after surgical intervention is uncertain. We aimed to determine the long-term efficacy of early initiation of infliximab following surgery among PFCD patients. METHODS: We performed a retrospective cohort study of PFCD patients who received combined infliximab and surgical treatment between 2010 and 2018 at a tertiary referral hospital. Patients were grouped according to the time interval between surgery and infliximab infusion, with < 6 weeks into early infliximab induction group and > 6 weeks into delayed infliximab induction group. The primary outcome was to compare surgical re-intervention between early and delayed infliximab induction groups. The secondary outcomes were fistula healing and predictors associated with these outcomes of early infliximab induction approach. RESULTS: One hundred and seventeen patients were included (73 in early infliximab induction, 44 in delayed infliximab induction). The median interval between surgery and infliximab initiation was 9.0 (IQR 5.5-17.0) days in early infliximab induction group and 188.0 (IQR 102.25-455.75) days in delayed infliximab induction group. After followed-up for a median of 36 months, 61.6% of patients in early infliximab induction group and 65.9% in delayed infliximab induction group attained fistula healing (p = 0.643). The cumulative re-intervention rate was 23%, 32%, 34% in early infliximab induction group and 16%, 25%, 25% in delayed infliximab induction group, at 1, 2, and 3 years respectively (p = 0.235). Presence of abscess at baseline (HR = 5.283; 95% CI, 1.61-17.335; p = 0.006) and infliximab maintenance therapy > 3 infusions (HR = 3.691; 95% CI, 1.233-11.051; p = 0.02) were associated with re-intervention in early infliximab induction group. Presence of abscess at baseline also negatively influenced fistula healing (HR = 3.429, 95% CI, 1.216-9.668; p = 0.02). CONCLUSION: Although no clear benefit was shown compared with delayed infliximab induction group, early initiation of infliximab after surgery could achieve promising results for PFCD patients. Before infliximab infusion, durable drainage is required for patients with concomitant abscess or prolonged infliximab maintenance therapy.
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Doença de Crohn , Fístula Retal , Doença de Crohn/tratamento farmacológico , Drenagem , Fármacos Gastrointestinais/uso terapêutico , Humanos , Infliximab/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento , Inibidores do Fator de Necrose TumoralRESUMO
BACKGROUND: Cytomegalovirus (CMV) has high seroprevalence, and its active infection is associated with several adverse prognoses in adult patients with acute respiratory distress syndrome (ARDS). However, the role of active CMV infection in ARDS-associated fibroproliferation is unknown. This study aimed at determining the association between active CMV infection and lung fibroproliferation in adult patients with ARDS. METHODS: We retrospectively reviewed the medical records of all adult patients with ARDS who were admitted to the intensive care unit (ICU) from January 2018 to December 2020 at a national university-affiliated hospital in China. Study subjects were divided into active and non-active CMV infection groups based on CMV DNAemia within a 28-day ICU hospitalization. Lung fibroproliferation was measured using chest high-resolution computed tomography (HRCT) and N-terminal peptide of serum procollagen III (NT-PCP-III) within the first 28 days of ICU admission. Pulmonary fibrosis, clinical features, laboratory findings, treatment measures, and clinical outcomes were compared between the two groups. RESULTS: Among the 87 ARDS patients included in this study, the incidence of active CMV infection was 16.1% within the 28-day ICU admission period. In logistic regression analyze, active CMV infection was found to be associated with higher pulmonary fibrogenesis, pulmonary fibrosis score, and NT-PCP-III level (P < 0.05). The duration of ICU stay in ARDS patients with active CMV infection was significantly higher than in those without active CMV infection (P < 0.05). CONCLUSIONS: Among adult patients with ARDS, active CMV infection was related to poor clinical outcomes. Active CMV infection was associated with ARDS-associated fibroproliferation. Prophylactic and preemptive use of anti-CMV agents on pulmonary fibrosis should be assessed to determine a consensus therapeutic strategy.
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Infecções por Citomegalovirus , Fibrose Pulmonar , Síndrome do Desconforto Respiratório , Adulto , Citomegalovirus , Infecções por Citomegalovirus/complicações , Humanos , Unidades de Terapia Intensiva , Pulmão , Pró-Colágeno , Fibrose Pulmonar/etiologia , Estudos Retrospectivos , Estudos SoroepidemiológicosRESUMO
In recent years, sexual assault cases have been on the rise, seriously infringing the legitimate rights and interests of women and children, causing widespread concern in society. DNA evidence has become the key evidence to prove the facts in sexual assault cases, but lack of DNA evidence or only DNA evidence in some sexual assault cases leads to unclear facts and insufficient evidence. With the emergence of high-throughput sequencing technology and the development of bioinformatics and artificial intelligence, new progress has been made in the study of human microbiome. Researchers have begun to use human microbiome for difficult sexual assault cases indentification. This paper reviews the characteristics of human microbiome, and its application value in the inferences of the body fluid stain origin, the sexual assault method, the crime time, etc. In addition, the challenges faced by the application of the human microbiome in practical case handling, the solutions and future development potential are analyzed and prospected.
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Vítimas de Crime , Microbiota , Delitos Sexuais , Criança , Humanos , Feminino , Inteligência Artificial , Medicina Legal/métodos , DNARESUMO
A molecular-level understanding of CO adsorption behavior would be greatly beneficial to resolving the problem of CO poisoning in fuel cells and medical science. Herein, an efficient borrowing strategy based on surface enhanced Raman scattering (SERS) has been developed to investigate the adsorption behavior of CO at the gas-solid interface. A composite SERS substrate with high uniformity was fabricated by electrochemical deposition of optimal Pt over-layers onto an Au nanoparticle film. The results indicated that the linearly bonded mode follows the Langmuir adsorption curve (type I), while the multiply bonded did not. It took a longer time for the C-OM vibration to reach the adsorption equilibrium than that of C-OL. The variation tendency toward the Pt-COL frequency was in opposition to that of C-OL, caused by the chemical and dipole-dipole coupling effects. The increase in dynamic coupling effects of the CO molecules caused a blue shift in νCO and a red shift of the Pt-CO band, while its shielding effect on SERS intensity cannot be ignored. Additionally, higher pressure is more conducive for linear adsorption to achieve saturation. Density functional theory calculations were employed to explore the adsorption mechanisms. It should also be noted that the substrate with good recycling performance greatly expands its practical application value. The present study suggested that the SERS-based borrowing strategy shows sufficient even valuable capacity to investigate gas adsorption kinetics behavior.
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BACKGROUND To analyze the risk factors of anorectal stenosis associated with perianal fistulizing Crohn's disease (PFCD). MATERIAL AND METHODS We retrospectively analyzed 139 cases of PFCD from January 2010 to December 2017 at the Affiliated Hospital of Nanjing University of Chinese Medicine. They were divided into 2 groups according to whether anorectal stenosis occurred. The possible factors associated with anorectal stenosis of PFCD were selected based on the literature review and clinical observations. Univariate analysis was performed to screen the risk factors of anorectal stenosis, and multivariate logistic regression analysis was performed on these risk factors and factors that were clinically considered to be potentially influential, to screen out the independent risk factors of anorectal stenosis. RESULTS We found that 44 cases (31.7%) of PFCD were associated with anorectal stenosis. Univariate analysis showed that CDAI, lesion location, and age at diagnosis were risk factors for anorectal stenosis of PFCD. Logistic regression analysis showed that mild (fair to good) (OR=3.833, 95% CI: 1.123~13.080) to moderate (poor) (OR=7.345, 95% CI: 1.964~27.474) CDAI and age at diagnosis (OR=1.067, 95% CI: 1.013~1.124) were independent risk factors for anorectal stenosis of PFCD. CONCLUSIONS Higher CDAI and older age at diagnosis appear to confer higher risk of anorectal stenosis associated with PFCD.
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Malformações Anorretais , Doença de Crohn/complicações , Fístula Retal , Adulto , Fatores Etários , Idade de Início , Malformações Anorretais/diagnóstico , Malformações Anorretais/epidemiologia , China/epidemiologia , Doença de Crohn/epidemiologia , Feminino , Humanos , Pessoa de Meia-Idade , Fístula Retal/diagnóstico , Fístula Retal/epidemiologia , Fístula Retal/etiologia , Estudos Retrospectivos , Medição de Risco/métodos , Fatores de Risco , Índice de Gravidade de DoençaAssuntos
Neoplasias do Endométrio , Neoplasias Pancreáticas , Humanos , Feminino , Biópsia por Agulha Fina , Biópsia Guiada por Imagem , Neoplasias do Endométrio/diagnóstico por imagem , Instrumentos Cirúrgicos , Ultrassonografia de Intervenção , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Neoplasias Pancreáticas/patologiaRESUMO
The use of fluorescence probes for biomedical imaging has attracted significant attention over recent years owing to their high resolution at cellular level. The probes are available in many formats including small particle size based imaging agents which are considered to be promising candidates, due to their excellent stabilities. Yet, concerns over the potential cytotoxicity effects of inorganic luminescent particles have led to questions about their suitability for imaging applications. Exploration of alternatives inspired us to use organic fluorophores with aggregation-induced emission (AIE), prepared by functionalizing the amine group on tetraphenylethene with 3,5-bis(trifluoromethyl)phenyl isocyanate. The as-synthesized novel AIE fluorophore (TPE-F) display enhanced quantum yield and longer lifetime as compared with its counterparts (4,4',4â³,4â´-(ethene-1,1,2,2-tetrayl)tetraaniline, TPE-AM). Furthermore, the TPE-F was encapsulated into small-size organic nanoparticles (NPs; dynamic light scattering size, â¼10 nm) with polysuccinimide (PSI). The biocompatibility, excellent stability, bright fluorescence, and selective cell targeting of these NPs enable the as-prepared TPE-F NPs to be suitable for specific fluorescence cell imaging.
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Corantes Fluorescentes/química , Microscopia Confocal , Nanopartículas/química , Difusão Dinâmica da Luz , Células HeLa , Humanos , Espectroscopia de Ressonância Magnética , Polímeros/químicaRESUMO
Self-assembly of metal nanoparticles has attracted considerable attention because of its unique applications in technologies such as plasmonics, surface-enhanced optics, sensors, and catalysts. However, fabrication of ordered nanoparticle structures remains a significant challenge. Thus, developing an efficient approach for the assembly of large-scale Au nanoparticles films for theoretical studies and for various applications is highly desired. In this paper, a facial approach for fabricating a monolayer film of Au nanoparticles was developed successfully. Using the surfactant polyvinylpyrrolidone (PVP), a large-scale monolayer film of well-ordered, uniform-sized Au nanoparticles was fabricated at the air/water interface. The film exhibited a two-dimensional (2D) hexagonal close-packed (HCP) structure having interparticle gaps smaller than 2 nm. These gaps generated numerous uniform "hot spots" for surface-enhanced Raman scattering (SERS) activity. The as-prepared monolayer film could be transferred to a solid substrate for use as a suitable SERS substrate with high activity, high uniformity, and high stability. The low spot-to-spot and substrate-to-substrate variations of intensity (<10%), the large surface enhancement factor (â¼10(6)), and the high stability (â¼45 days) make the substrate suitable for SERS measurements. Transfer of the monolayer film onto a glassy carbon electrode produced an Au electrode with clean, well-defined nanostructure suitable for electrochemical SERS measurements. The adsorption process of ionic liquids on the electrode with the monolayer film is similar to that on bulk metal electrodes. The present strategy provides an effective way for self-assembly of Au nanoparticles into well-defined nanostructures that may form optimal reproducible SERS substrates for quantitative analysis. It also provides an electrode with clean, well-defined nanostructure for electrochemical investigations.
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The SiO2 shell with the thickness of 4 nm was attached onto high surface enhanced Raman spectroscopy (SERS) active Au core nanoparticles to obtain Au@SiO2 core shell nanoparticles by the hydrolysis of sodium silicate solution with the boiling water bath. The inert shell of SiO2 isolated the direct interaction of Au nanoparticles and probe molecules. The stable, compact and uniform monolayer nanoparticles film was self assembled at water/oil interface, and one to six monolayers film was transferred to Si wafer as SERS substrates through layer by layer technique. The relationship between the SERS activities and layers of the monolayer nanoparticles film on Si surface was investigated. The SERS mapping was developed to determine the layers of the Au@SiO2 film. The coupling effect among the Au@SiO2 films was explored by changing the adsorption location of the probe on the multilayer films. The result revealed that the monolayer film was a favourable candidate with high-quality performances for the SERS application. The SERS signal was distributed on the surface with high uniformity at the same monolayer film, and it was enhanced in the intensity with the increase in film layers. It reached the maximun intensity as the film was over five layers. It indicated that the SERS signal was contributed mainly by the first five monolayers. The probe molecules were immobilized onto the first monolayer nanoparticles film, and the SERS signal from the probe approached to the maximum as the second monolayer covered the probe modified first nanoparticles film. It was dominated by the coupling effect ("hot spots") of the adjacent layers. The SERS signal decreased in intensity when the third layer was transferred onto the second layer, and it disappeared after the fouth layer was covered, mainly duo to the shield of the nanoparticles film to the incident laser and Raman signal. The preliminary results provided guidance for fabricating optimal SERS substrates.
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Introduction: The management of nutritional risk has garnered significant attention in individuals diagnosed with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) due to the high prevalence of malnutrition and its correlation with unfavorable outcomes. While numerous rating scales exist to assist in assessment for both clinical and research purposes, there is considerable variability in the selection of scales based on the characteristics of the study participants and the study design. The objective of this study was to examine the efficacy of the Geriatric Nutritional Risk Index (GNRI) and Prognostic Nutritional Index (PNI) in identifying malnutrition and predicting prognosis in elderly AECOPD patients. Methods: From January 2022 to December 2022, a consecutive inclusion of elderly AECOPD patients admitted to the First Affiliated Hospital of Zhengzhou University was conducted. Diagnosing malnutrition in patients using PNI and GNRI, comparing the results with the diagnostic outcomes based on the Global Leadership Initiative on Malnutrition (GLIM) criteria through Receiver Operating Characteristic curves. Logistic regression analysis was employed to assess the risks associated with length of stay (LOS), hospitalization costs, and Charlson Comorbidity Index (CCI) based on GLIM, GNRI, or PNI. Results: A total of 839 elderly AECOPD patients were investigated in the study. The GNRI and PNI demonstrated a sensitivity of 89.5 and 74.1%, specificity of 77.2 and 66.4%, and an area under the curve of 0.834 and 0.702, respectively. The identification of high malnutrition-risk cases using the GLIM, GNRI and PNI were associated with a significant increase in the risk of LOS over 7 days [odds ratio (95% CI) for GLIM, GNRI, PNI: 1.376 (1.033-1.833); 1.405 (1.070-1.846); 1.875 (1.425-2.468)] and higher hospitalization expenses [OR (95% CI) for GLIM, GNRI: 1.498 (1.080-2.080); 1.510 (1.097-2.079)], but not with the CCI. Conclusion: According to our study, it is possible to use GNRI and PNI as alternatives to GLIM in the context of AECOPD, which makes it easier to identify malnutrition. The utilization of GNRI and PNI as alternatives to GLIM in the context of AECOPD enables the identification of malnutrition. The presence of malnourished individuals experiencing AECOPD is correlated with higher probabilities of extended hospital stays and escalated in-hospital expenses.
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The electrochemical reduction of nitrate to ammonia (NO3RR) provides a desired alternative of the traditional Haber-Bosch route for ammonia production, igniting a research boom in the development of electrocatalysts with high activity. Among them, molecular electrocatalysts hold considerable promise for the NO3RR, suppressing the competing hydrogen evolution reaction. However, the complicated synthesis procedure, usage of environmentally unfriendly organic solvents, and poor stability of Cu-based molecular electrocatalysts greatly limit their employment in NO3RR, and the development of desired Cu-based molecular catalysts remains challenging. Herein, a simple nonorganic solvent involving a one-step strategy was proposed to synthesize d-π-conjugated molecular electrocatalysts metal-amidinothiourea (M-ATU). Cu-ATU is composed of Cu coordinated with two S and two N atoms, whereas Ni-ATU is formed by Ni with four N atoms from two ATU ligands. Remarkably, Cu-ATU with a Cu-N2S2 coordination configuration exhibits superior NO3RR activity with a NH3 yield rate of 159.8 mg h-1 mgcat-1 (-1.54 V) and Faradaic efficiency of 91.7% (-1.34 V), outperforming previously reported molecular catalysts. Compared to Ni-ATU, Cu-ATU transfers more electrons to the *NO intermediate, effectively breaking the strong sp2 hybridization system and weakening the energy of NâO bonds. The increase in free energy of *NO reduced the energy barriers of the rate-determining step, facilitating the further hydrogenation process over Cu-ATU. Our work opened up a new horizon for exploring molecular electrocatalysts for nitrate activation and paved a way for the in-depth understanding of catalytic behaviors, aligning more closely with industrial demands.
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Monitored natural attenuation (MNA) of chlorinated ethenes (CEs) has proven to be a cost-effective and environment-friendly approach for groundwater remediation. In this study, the complete dechlorination of CEs with formation of ethene under natural conditions, were observed at two CE-contaminated sites, including a pesticide manufacturing facility (PMF) and a fluorochemical plant (FCP), particularly in the deeply weathered bedrock aquifer at the FCP site. Additionally, a higher abundance of CE-degrading bacteria was identified with heightened dechlorination activities at the PMF site, compared to the FCP site. The reductive dehalogenase genes and Dhc 16 S rRNA gene were prevalent at both sites, even in groundwater where no CE dechlorination was observed. vcrA and bvcA was responsible for the complete dechlorination at the PMF and FCP site, respectively, indicating the distinct contributions of functional microbial species at each site. The correlation analyses suggested that Sediminibacterium has the potential to achieve the complete dechlorination at the FCP site. Moreover, the profiles of CE-degrading bacteria suggested that dechlorination occurred under Fe3+/sulfate-reducing and nitrate-reducing conditions at the PMF and FCP site, respectively. Overall these findings provided multi-lines of evidence on the diverse mechanisms of CE-dechlorination under natural conditions, which can provide valuable guidance for MNA strategies implementation.
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Chloroflexi , Água Subterrânea , Poluentes Químicos da Água , Biodegradação Ambiental , Bactérias/genética , Etilenos , Água Subterrânea/microbiologiaRESUMO
Coptisine (COP) has been shown to exhibit a wide range of anticancer properties, including in hepatocellular carcinoma (HCC). Nevertheless, the precise mechanism of COP in the treatment of HCC remains elusive. This study aims to investigate the potential mechanism of action of COP against HCC. By evaluating the anti-HCC activity of COP in different HCC cells lines and in xenografted nude mice, it was found that COP inhibited HCC in vitro and in vivo. Through RNA-Seq analysis, E2F7 was identified as a potential target of COP against HCC, as well as the cell cycle as a possible pathway. The overexpression of E2F7 and the inhibition of CHK1 demonstrated that COP inhibits the activity of HCC and induces G2/M phase arrest of HCC cells by down-regulating E2F7 and influencing the CHK1/CDC25A pathway. Finally, the promoter fragmentation experiments and chromatin immunoprecipitation revealed that COP down-regulated E2F7 by inhibiting the E2F4/NFYA/NFYB transcription factors. In conclusion, our study demonstrated that COP downregulates E2F7 by affecting key transcription factors, thereby inducing cell cycle arrest and inhibits HCC cell growth. This provides further evidence of the efficacy of COP in the treatment of tumors.
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Berberina , Carcinoma Hepatocelular , Regulação para Baixo , Fator de Transcrição E2F4 , Fator de Transcrição E2F7 , Pontos de Checagem da Fase G2 do Ciclo Celular , Neoplasias Hepáticas , Camundongos Nus , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Berberina/farmacologia , Berberina/análogos & derivados , Animais , Regulação para Baixo/efeitos dos fármacos , Camundongos , Fator de Transcrição E2F4/metabolismo , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Fator de Transcrição E2F7/metabolismo , Fator de Transcrição E2F7/genética , Linhagem Celular Tumoral , Camundongos Endogâmicos BALB C , Proliferação de Células/efeitos dos fármacos , Quinase 1 do Ponto de Checagem/metabolismo , Quinase 1 do Ponto de Checagem/antagonistas & inibidoresRESUMO
Deduced from thermodynamics and the Thomson-Gibbs equation that the surface energy of crystal face is in proportion to the supersaturation of crystal growth units during the crystal growth, we propose that the exposed crystal faces can be simply tuned by controlling the supersaturation, and higher supersaturation will result in the formation of crystallites with higher surface-energy faces. We have successfully applied it for the growth of ionic (NaCl), molecular (TBPe), and metallic (Au, Pd) micro/nanocrystals with high-surface-energy faces. The above proposed strategy can be rationally designed to synthesize micro/nanocrystals with specific crystal faces and functionality toward specific applications.
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Ouro/química , Nanopartículas/química , Paládio/química , Fenolftaleínas/química , Cloreto de Sódio/química , Íons/química , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície , TermodinâmicaRESUMO
A new approach was developed for the magnetic separation of copper(II) ions with easy operation and high efficiency. p-Mercaptobenzoic acid served as the modified tag of Fe2O3@Au nanoparticles both for the chelation ligand and Raman reporter. Through the chelation between the copper(II) ions and carboxyl groups on the gold shell, the Fe2O3@Au nanoparticles aggregated to form networks that were enriched and separated from the solution by a magnet. A significant decrease in the concentration of copper(II) ions in the supernatant solution was observed. An extremely sensitive method based on surface-enhanced Raman spectroscopy was employed to detect free copper(II) ions that remained after the magnetic separation, and thus to evaluate the separation efficiency. The results indicated the intensities of the surface-enhanced Raman spectroscopy bands from p-mercaptobenzoic acid were dependent on the concentration of copper(II) ions, and the concentration was decreased by several orders of magnitude after the magnetic separation. The present protocol effectively decreased the total amount of heavy metal ions in the solution. This approach opens a potential application in the magnetic separation and highly sensitive detection of heavy metal ions.
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Cobre/isolamento & purificação , Fenômenos Magnéticos , Análise Espectral Raman , Benzoatos/química , Íons/isolamento & purificação , Compostos de Sulfidrila/química , Propriedades de SuperfícieRESUMO
Progonocimicids are one of key representatives from the Middle-Late Jurassic Daohugou biota, the early assemblage of the Yanliao biota. Here we describe a new progonocimicid species, Cicadocoris henanensis sp. nov., from the Middle Jurassic Jiyuan Basin in central China. This not only represents a novel case indicating the abundance of progonocimicids during the Jurassic but also provides additional evidence substantiating the stratigraphic correlation between the Yangshuzhuang Formation in the Jiyuan Basin and the Haifanggou Formation in the Yanliao Region.
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Hemípteros , Animais , Fósseis , China , BiotaRESUMO
The odonatan asiopterid Turanopteron sinensis sp. nov. and the juragomphid Oxfordgomphus trescellulae gen. et sp. nov. are described on the basis of two new fossil wings from the Middle-Upper Jurassic of Henan Province in China. These taxa belong to ancient, Toarcian epiproctophoran stem groups of Anisoptera Selys, 1854. They show important affinities with taxa from the Karatau entomofauna in Kazakhstan. These groups progressively decrease and were replaced by more modern clades of Anisoptera during the Late Jurassic.