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1.
Environ Sci Process Impacts ; 26(5): 928-941, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38635247

RESUMEN

Motor vehicles are among the major sources of pollutants and greenhouse gases in urban areas and a transition to "zero emission vehicles" is underway worldwide. However, emissions associated with brake and tire wear will remain. We show here that previously unrecognized volatile and semi-volatile organic compounds, which have a similarity to biomass burning emissions are emitted during braking. These include greenhouse gases or, these classified as Hazardous Air Pollutants, as well as nitrogen-containing organics, nitrogen oxides and ammonia. The distribution and reactivity of these gaseous emissions are such that they can react in air to form ozone and other secondary pollutants with adverse health and climate consequences. Some of the compounds may prove to be unique markers of brake emissions. At higher temperatures, nucleation and growth of nanoparticles is also observed. Regions with high traffic, which are often disadvantaged communities, as well as commuters can be impacted by these emissions even after combustion-powered vehicles are phased out.


Asunto(s)
Contaminantes Atmosféricos , Monitoreo del Ambiente , Emisiones de Vehículos , Compuestos Orgánicos Volátiles , Compuestos Orgánicos Volátiles/análisis , Contaminantes Atmosféricos/análisis , Emisiones de Vehículos/análisis , Monitoreo del Ambiente/métodos , Contaminación del Aire/estadística & datos numéricos , Vehículos a Motor
2.
Histopathology ; 78(2): 252-264, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32654226

RESUMEN

AIMS: Tumour budding (TB), desmoplastic reaction (DR) and intraepithelial tumour infiltrating lymphocytes (iTILs) are recently recognised prognostic factors in colorectal cancer (CRC). In this study, we evaluated their significance and relationship to each other and their cumulative effect on survival. METHODS AND RESULTS: A total of 372 stages I-III CRC cases from 2013 to 2016 were included. Low TB was identified in 302 (81%) cases, immature/myxoid DR in 67 (18%) cases and iTILs in 130 (35.0%) cases. iTILs was associated with low budding (P = 0.0247), non-myxoid DR (P = 0.0004), poorly differentiated histology (P = 0.0015), absence of perineural invasion (P = 0.0367) and loss of mismatch repair proteins (P = 0.0002). Absence of iTILs and presence of immature/myxoid DR were associated with a worse recurrence-free survival (RFS) [hazard ratio (HR) = 2.191, 95% confidence interval (CI) = 1.232-3.895; and HR = 5.706, 95% CI = 3.632-8.964, respectively]. A competing risk analysis showed statistically significant prognostic groups combining iTILs and TB (P < 0.0001). Cases with iTILs and low TB were associated with better RFS compared to cases without iTILs and with intermediate/high TB (HR = 0.214, 95% CI = 0.109-0.421). Similarly, combining iTILs and DR revealed statistically significant prognostic groups (P < 0.0001). Cases with iTILs and a non-myxoid DR had better RFS compared to cases without iTILs and immature/myxoid DR (HR = 0.113, 95% CI = 0.056-0.230). On multivariate cause-specific analysis, patients' age (P = 0.0045), iTILs (P = 0.0345), DR (P < 0.0001) and pTNM prognostic groups (P < 0.0001) were associated with RFS. CONCLUSIONS: Our study validates the association of iTILs and DR as independent prognostic finding in CRC, and propose a prognostic model using the combinations of iTILs with TB and stromal reaction in CRC.


Asunto(s)
Neoplasias Colorrectales/patología , Linfocitos Infiltrantes de Tumor/patología , Pronóstico , Adulto , Anciano , Neoplasias del Colon/patología , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Modelos de Riesgos Proporcionales , Medición de Riesgo
3.
Sci Adv ; 6(22): eaay4945, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32518819

RESUMEN

Atmospheric new-particle formation (NPF) affects climate by contributing to a large fraction of the cloud condensation nuclei (CCN). Highly oxygenated organic molecules (HOMs) drive the early particle growth and therefore substantially influence the survival of newly formed particles to CCN. Nitrogen oxide (NOx) is known to suppress the NPF driven by HOMs, but the underlying mechanism remains largely unclear. Here, we examine the response of particle growth to the changes of HOM formation caused by NOx. We show that NOx suppresses particle growth in general, but the suppression is rather nonuniform and size dependent, which can be quantitatively explained by the shifted HOM volatility after adding NOx. By illustrating how NOx affects the early growth of new particles, a critical step of CCN formation, our results help provide a refined assessment of the potential climatic effects caused by the diverse changes of NOx level in forest regions around the globe.

4.
Nat Commun ; 10(1): 1122, 2019 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-30850597

RESUMEN

State-of-the-art aerosol nanoparticle techniques all have one feature in common: for analysis they remove the nanoparticles from their original environment. Therefore, physical and chemical properties of the particles might be changed or cannot be measured correctly. To overcome these shortcomings, we apply synchrotron based small angle X-ray scattering (SAXS) as an in-situ measurement technique. Contrasting other aerosol studies using SAXS, we focus on particle concentrations which allow direct comparison to common aerosol nanoparticle analyzers. To this end, we analyze aerosol nanoparticles at ambient pressure and concentrations of slightly above ~106 cm-3. A differential mobility particle sizer (DMPS) is operated in parallel. We find that SAXS enables measurement of the primary particles and the aggregates, whereas the DMPS detects only aggregates. We conclude that in-situ nanoparticle characterization with ultra-low volume fractions of ~10-10 is feasible with SAXS. Our technique opens up a doorway to the in-situ analysis of aerosol nanoparticles under atmospheric conditions.

5.
Sci Rep ; 6: 26111, 2016 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-27183880

RESUMEN

Wetting phenomena in multi-phase systems govern the shape of the contact line which separates the different phases. For liquids in contact with solid surfaces wetting is typically described in terms of contact angle. While in macroscopic systems the contact angle can be determined experimentally, on the molecular scale contact angles are hardly accessible. Here we report the first direct experimental determination of contact angles as well as contact line curvature on a scale of the order of 1nm. For water nucleating heterogeneously on Ag nanoparticles we find contact angles around 15 degrees compared to 90 degrees for the corresponding macroscopically measured equilibrium angle. The obtained microscopic contact angles can be attributed to negative line tension in the order of -10(-10) J/m that becomes increasingly dominant with increasing curvature of the contact line. These results enable a consistent theoretical description of heterogeneous nucleation and provide firm insight to the wetting of nanosized objects.

6.
J Med Syst ; 8(1-2): 55-63, 1984 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6429262

RESUMEN

The Case Mix System (CMS) was developed as a broad-based decision support system for planning and managing effectiveness in the product line environment. CMS is proven in a range of hospital settings and provides the information needed to meet todays health care management challenges.


Asunto(s)
Costos y Análisis de Costo , Grupos Diagnósticos Relacionados , Economía Hospitalaria , Administración Financiera de Hospitales , Administración Hospitalaria , Humanos , Estados Unidos
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