Intracranial Seeding Following Surgery and Chemotherapy in a Child with a Spinal Cord Endodermal Sinus Tumor: A Case Report.

We herein report a case of an extremely rare spinal cord endodermal sinus tumor (EST). A nine-year-old boy presented with progressive paraparesis, hypesthesia, and urinary retention. Gadolinium-enhanced magnetic resonance imaging (MRI) revealed multiple intradural enhancing lesions at T1 to T9 without evidence of intracranial tumors.

A machine learning model for predicting PM and nitrate concentrations based on long-term water-soluble inorganic salts datasets at a road site station.

In this study, long-term variations in the concentrations of PM, water-soluble inorganic salts (WIS), and gaseous precursors measured by a roadside air quality monitoring station were investigated from 2017 to February 2021 to examine the formation mechanism of secondary inorganic PM. A new machine learning model using WIS data as input variables was further developed to predict PM and nitrate concentrations for source tracing and effective control strategy development. The results showed that a reduction in the NO concentration under VOC-limited O formation regime could offset the consumption of OH and O, causing an increase in secondary NO and PM formation during fall and winter seasons.

WRF modeling of PM remediation by SALSCS and its clean air flow over Beijing terrain.

Atmospheric simulations were carried out over the terrain of entire Beijing, China, to investigate the effectiveness of an air-pollution cleaning system named Solar-Assisted Large-Scale Cleaning System (SALSCS) for PM mitigation by using the Weather Research and Forecasting (WRF) model. SALSCS was proposed to utilize solar energy to generate airflow therefrom the airborne particulate pollution of atmosphere was separated by filtration elements. Our model used a derived tendency term in the potential temperature equation to simulate the buoyancy effect of SALSCS created with solar radiation on its nearby atmosphere.

Aerosol Emission Monitoring and Assessment of Potential Exposure to Multi-walled Carbon Nanotubes in the Manufacture of Polymer Nanocomposites.

Recent animal studies have shown that carbon nanotubes (CNTs) may pose a significant health risk to those exposed in the workplace. To further understand this potential risk, effort must be taken to measure the occupational exposure to CNTs. Results from an assessment of potential exposure to multi-walled carbon nanotubes (MWCNTs) conducted at an industrial facility where polymer nanocomposites were manufactured by an extrusion process are presented.

Novel active personal nanoparticle sampler for the exposure assessment of nanoparticles in workplaces.

A novel active personal nanoparticle sampler (PENS), which enables the collection of both respirable particulate mass (RPM) and nanoparticles (NPs) simultaneously, was developed to meet the critical demand for personal sampling of engineered nanomaterials (ENMs) in workplaces. The PENS consists of a respirable cyclone and a micro-orifice impactor with the cutoff aerodynamic diameter (d(pa50)) of 4 μm and 100 nm, respectively. The micro-orifice impactor has a fixed micro-orifice plate (137 nozzles of 55 μm in the inner diameter) and a rotating, silicone oil-coated Teflon filter substrate at 1 rpm to achieve a uniform particle deposition and avoid solid particle bounce.

Cholesteric liquid crystal devices with nanoparticle aggregation.

A broadband cholesteric liquid crystal (CLC) device with a multi-domain structure is demonstrated by using an aggregation of polyhedral oligomeric silsesquioxane (POSS) nanoparticles in the CLC layer. The aggregation pattern of the self-assembled POSS nanoparticles depends on the concentration of POSS doped in the mixture of POSS/CLC and the cooling rate of the mixture from a temperature higher than the clear point. POSS-induced changes in the bulk and surface properties of the cholesteric cells, such as a promotion of homeotropic alignment, help to form a cholesteric structure with a broadband reflection of light; the latter can be used for improvement of bistable CLC devices.

Study of an axial flow cyclone to remove nanoparticles in vacuum.

An axial flow cyclone for removing nanoparticles was tested for collection efficiency. Data were validated numerically in vacuum conditions of several Torrs, with flow rates of 0.35-0.