RESUMO
The occurrence of chlorinated derivatives of bisphenol S (Clx-BPS) and BPS was investigated in nine types of paper products (n = 125), including thermal paper, corrugated boxes, mail envelopes, newspapers, flyers, magazines, food contact paper, household paper, and business cards. BPS was found in all paper product samples, while Clx-BPS were mainly found in thermal paper (from below the limit of detection (Assuntos
Compostos Benzidrílicos
, Papel
, Humanos
, Alimentos
, Comércio
RESUMO
Morphological regulation and defect engineering are efficient methods for photocatalytic technology by improving photon absorption and electron dissociation. Herein, In2S3-x hollow microtubes with S-vacancies (MIS) were fabricated via a simple solvothermal reaction using In-based metal-organic frameworks (In-MOFs) as a precursor. Experimental results demonstrate that the hollow structure and optimal S-vacancies can jointly accelerate the photocatalytic reaction, attributed to a larger specific surface area, more active sites, and faster electron transfer efficiency. The champion MIS(2) displayed significantly better photocatalytic activity for Cr(VI) reduction and tetracycline (TC) degradation. The Cr(VI) reduction rate by MIS(2) is 3.67 and 2.82 times higher than those of optimal In2S3 template-free (HIS(2)) and MIS(1) with poor S-vacancies, respectively. The removal efficiency of TC by MIS(2) is 1.37 and 1.15 times higher than those of HIS(2) and MIS(1). Further integration of MIS(2) with aerogel simplifies the recovery process significantly.
Assuntos
Cromo , Luz , Cromo/química , Tetraciclina , Antibacterianos , Enxofre/químicaRESUMO
A MoS2-based nanotherapeutic platform was developed for synergetic photothermal and photodynamic anti-tumor therapy. AIEgens TFPy-SH molecules were intercalated into MoS2 nanosheets (MoS2 NSs) with S-deficiencies to give the nanocomposite MoS2-TFPy. The AIEgens intercalation expanded the interlayer spacing of MoS2 NSs and induced the transform of MoS2 crystal phase from 2H to 1T, offering MoS2-TFPy nanocomposite high molar absorption coefficient (5.65 L g-1 cm-1), excellent photothermal conversion efficiency under near-infrared (NIR) laser irradiation (38.3%), and favorable intracellular reactive oxygen species (ROS) generation capacity. The positively charged MoS2-TFPy were mainly distributed in mitochondria after cell up-taking, and achieved 1+1>2 anti-tumor effect attributed to its favorable photothermal and photodynamic properties. The high structure and physiological stability, favorable biocompatibility, excellent photothermal and photodynamic therapy effect make the MoS2-TFPy nanoplatform an promising candidate in biomedical clinical applications.
Assuntos
Nanocompostos , Fotoquimioterapia , Molibdênio , Mitocôndrias , Espécies Reativas de OxigênioRESUMO
PURPOSE: Audiological services are underused, possibly because patients need to drive long distances to see a provider. In this study, we measured the association of drive times to the nearest audiologist with population density, income, ethnicity, race, and distance to the nearest audiology graduate program. METHOD: Drive times for each census block group to the nearest audiologist were measured using census data, the National Provider Identifier Registry, and a geographic analyzing tool called ArcGIS for all block groups within the United States. The association between drive times and population density, income, ethnicity, race, and audiology program distance was evaluated with a population density-matched case-control study and multiple linear regression analyses. RESULTS: Approximately 5.29 million Americans need to drive at least 1 hr to visit their closest audiologist. The 10% most rural-dwelling Americans drive an average of 33.8 min. The population density-matched case-control study demonstrated that percent below poverty, percent identifying as Hispanic, and travel times to the nearest audiology program were all significantly higher in census block groups with high drive times to the nearest audiologist. An average of 7.96% of individuals in census block groups with low drive times identified as Hispanic, but 18.8% identified as Hispanic in high drive time groups. The multiple linear regression showed that the effect of demographics and distance to the nearest audiology program was highest in rural areas. In both analyses, adjusting for poverty did not drastically change the effect of percent identifying as Hispanic on drive times. CONCLUSIONS: Long drive times restrict access to audiological care for those who live in rural areas. This restriction disproportionately affects those in rural areas who identify as Hispanic or have low income.
RESUMO
The construction of covalent organic frameworks (COFs) with unique structures has great significance in exploring the structure-function relationship and extending their potential applications. Fibrous COFs have demonstrated superior performance in specific application scenarios owing to the distinctive three-dimensional (3D) structure. Herein, we report a facile strategy for the fabrication of 3D COF nanofiber by exploiting silver amalgam as a bridging agent to assemble one-dimensional-extended PA-COF modules into a tubular structure. Dimensions of the obtained 3D COF nanofiber were predicted by DFT calculations, and the nanofiber was endowed with the merits of favorable uniformity and high stability. Due to the enhanced exposure of conjugatable binding sites for dye retention offered by the novel 3D architecture, the PA-COF nanofiber exhibits fast adsorption (within 5 min) and superior adsorption capacity to various organic dyes, e.g., 1717 mg g-1 for methylene blue (MB) and 978.3 mg g-1 for methyl orange (MO). Moreover, the PA-COF nanofiber shows excellent reusability in dye adsorption, which makes it a potential medium for removing dye pollutants from wastewater. This work presents an effective strategy to construct COF materials with unique architecture and potential prospects in the fields of separation and wastewater treatment.
RESUMO
A simple and sensitive device for the detection of nitrite and nitrate in environmental waters was developed based on visible light gas-phase molecular absorption spectrometry. By integrating a detection cell (DC), semiconductor refrigeration temperature-controlling system (SRTCY), and nitrite reactor into a sequential injection analysis system, trace levels of nitrite and nitrate in complex matrices were successfully measured. A low energy-consuming light-emitting diode (violet, 400-405 nm) was coupled with a visible light-to-voltage converter (TSL257) to measure the gas-phase molecular absorption. To reduce the interference of water vapor, an SRTCY was used to condense the water vapor on-line before the gas-phase analyte entered the DC. The DC was radiatively heated by the SRTCY to avoid water vapor condensation in the light path. As a result, the obtained baseline noise reduced 3.75 times than that of without SRTCY. Under the optimized conditions, the device achieved limits of detection (3σ/k) of 0.055 and 0.36 mmol/L (0.77 and 5.04 mg N/L) for nitrite and nitrate, respectively, and the linear calibration ranges were 0.1-15 mmol/L (R2 = 0.9946) and 1-10 mmol/L (R2 = 0.9995), respectively. Precisions of 5.2 % and 9.0 % were achieved for ten successive determinations of 0.3 mmol/L nitrite and 1.0 mmol/L nitrate, and the analytical times for nitrite and nitrate determination were 5 and 13 min, respectively. This method was validated against standard methods and recovery tests, and it was applied to the measurement of nitrite and nitrate in environmental waters. Moreover, a device was designed to enable the field measurement of nitrite and nitrate in complex matrices.
RESUMO
To explore the characteristics, influencing factors, and effect of different treatments on the survival in patients with first primary cervical cancer (CC) and second primary CC. Data of 33,934 eligible patients with CC were extracted from the Surveillance, Epidemiology, and End Results (SEER) database in 2004-2015. We also included 176 patients with CC from the Affiliated Dongyang Hospital of Wenzhou Medical University. Univariate and multivariate Cox proportional hazard models were used to screen the potential influencing factors associated with the survival in patients with hazard ratios (HRs) and 95 % confidence intervals (CIs). Subgroup analyses of age, American Joint Committee on Cancer (AJCC) stages, tumor grades and histologic types were conducted to explore the association between different treatments and survival in different populations. The 5-year mortality was 43.08 % for patients with first primary CC and that was 58.13 % for patients with second primary CC. We found that the relationships between age, histologic type, tumor grade, tumor size, AJCC tumor-node-metastasis (TNM) stage, surgery, chemotherapy, radiotherapy and the first primary CC and second primary CC were different (all P < 0.05). Additionally, the results of subgroup analyses indicated that the choice of surgery, chemotherapy, and radiotherapy should be adjusted according to the different health conditions of the patients. In conclusion, the causal relationship between characteristics, influencing factors, and treatments and survival in patients with primary CC diagnosed as different time periods are needed further exploration.