Development of an Advanced Personal Nasal Sampler (Pns) to Assess Exposure to Bioaerosols

SSRN Electronic Journal · 2025-01-01

Performance characteristics of respirable parallel particle impactors (PPI)

Journal of Occupational and Environmental Hygiene · 2025-07-18 · 1 citations

of ∼4 µm, with a BPC of 100%. Overall, the respirable PPI samplers, particularly their disposable models, show excellent adherence to the respirable aerosol sampling convention and contribute to the arsenal of tools for estimating exposures to respirable particles. The availability of PPI samplers operating at different flow rates offers flexibility in selecting a suitable sampler model based on available personal sampling pumps, anticipated concentrations of the respirable aerosol fraction, and desired sampling times.

Assessment of ionization-type car air purifiers under actual driving conditions

Aerosol Science and Technology · 2024-12-20 · 2 citations

Antibiotic Resistant Bacteria and Genes in Bioaerosols at Wastewater Treatment Plant: Should I Be Worried?

Proceedings of the Water Environment Federation · 2024-10-01

Electrostatic battery for emissions control (ESBEC): Further development and testing with diesel emissions

International Journal of Engine Research · 2024-09-10 · 3 citations

We recently developed a novel diesel emissions control device, Electrostatic Screen Battery for Emissions Control (ESBEC), where an electrostatic mechanism removes diesel exhaust particles onto metal screens. In this study, we made the following improvements to the initial ESBEC’s design: (1) used metal collection screens of different porosity for a more even distribution of captured diesel exhaust throughout ESBEC, (2) redesigned screen holders for easy assembly of ESBEC, (3) heat-resistant materials were used to build the current model, which is 3 in. in diameter and 4 in. in length. ESBEC was investigated in a laboratory to optimize the screen porosity and configuration. Then, in the field, it was challenged with diesel particulate matter (DPM) exhausted from a diesel electric power generator. The DPM mass concentrations produced by the generator varied from 38 to 187 mg/m 3 , and air flow rates passing through ESBEC varied from 219 to 410 L/min. The testing was intermittently performed over 49 h. In addition, ESBEC’s particle collection efficiency was compared to that of a traditional diesel particulate filter (DPF). We also explored various washing methods to effectively remove DPM captured by ESBEC. When challenged with DPM, ESBEC showed collection efficiency of ∼100% for 26 h, during which 60 g of DPM was captured. For comparison, the collection efficiency of DPF was ∼77%. After the total run time of 46 h, the collection efficiency of ESBEC decreased to CARB (California Air Resources Board) Level 3 (85%), with 102 g DPM accumulated. When ESBEC was operated beyond 46 h, its collection efficiency was <85%. However, washing screens for 5 min in isopropyl alcohol restored the collection efficiency to 86%. Future studies will examine the performance of ESBEC when it is installed in an actual diesel-powered vehicle.

Performance evaluation of different low-cost DIY air cleaner configurations

Aerosol Science and Technology · 2023-08-23 · 8 citations

Do-it-yourself (DIY) air cleaners have been proposed as an affordable alternative to expensive portable HEPA air cleaners; however, their performance data is still limited. This study evaluated the performance of single- and multi-filter DIY air cleaner configurations with different filter thickness (1, 2, and 4 inches) and MERV ratings (8, 11, and 13). The filters were selected based on their availability to the public, with the resulting cost of less than 50 and 100 USD for single- and multi-filter configurations, respectively. DIY air cleaners were challenged with polydisperse NaCl particles, and their clean air delivery rate (CADR) was determined for ultrafine (< 100 nm) and 300 nm particle number concentration and PM_2.5 mass concentration. Twelve single-filter configurations with filters from three companies, a 2-filter configuration, and a Corsi-Rosenthal (C-R) box with four 2-inch filters were tested. The CADR ranged from 84 to 635 cfm, depending on the particle metric and filter configuration. Among the single-filter configurations, the 4-inch filter performed the best. The multi-filter models, especially the C-R box, demonstrated the highest CADR: comparable to and exceeding the CADR of portable HEPA air cleaners. In addition, the C-R box also provided the highest CADR per power input while resulting in the lowest noise level and fan motor temperature. In addition to performance, the cost of operating and maintaining DIY air cleaners is also discussed. Overall, this study shows that DIY air cleaners are an affordable and effective means to reduce particulate air pollutants, thus improving indoor air quality. Copyright © 2023 American Association for Aerosol Research

Development and optimization of Stationary Electrostatic Bioaerosol Sampler (SEBS) for viable and culturable airborne microorganisms

Journal of Aerosol Science · 2022 · 10 citations

• Environmental science
• Environmental chemistry
• Chemistry

Data for "CAIT-UTC-REG58: Supplemental Study of Filter Technology Efficacy for Transit Vehicles to Combat the Spread of COVID-19 and Other Respiratory Infections"

Harvard Dataverse · 2022-12-07

The COVID-19 pandemic has been a worldwide issue that transit agencies are still struggling to find cost-efficient solutions to. Upgrading the filters used on trains and buses to reduce the airborne transmission of the SARS-CoV-2 virus as well as other infectious viruses, such as influenza, may be an effective, cost-efficient way of containing the very small, hard-to-filter droplet and aerosol particles that these viruses may travel within. One way to improve transit vehicle air quality and safety is to upgrade the current MERV-rated filters to higher-rated ones such as a MERV 13 filter. This study looked at quantifying the upgraded filters’ performance, focusing on their efficacy over time and comparing them to a MERV 8 filter. Filter performance was investigated using sodium chloride (NaCl) particles and Arizona Road Dust (ARD) particles to determine the filter collection efficiency. A Grimm MiniWras and Aerodynamic Particle Sizer was used to compare the number concentrations (#/L) of particles upstream and downstream of the filter. The filter testing data confirm that MERV-13 filters have better filtration efficiency compared to MERV-8 filters but the filter performance varies depending on the age of the filter (i.e., its loading), particle type, and particle properties (charged vs. neutralized).

Development and initial testing of an active low-power, ferroelectric film-based bioaerosol sampler

Aerosol Science and Technology · 2022-09-26 · 3 citations

This article introduces REAS (Rutgers Electrostatic Active Sampler), a new active bioaerosol sampler using permanently polarized ferroelectric film (e.g., PVDF) to capture charge-carrying bioaerosol particles. While REAS operates on an electrostatic collection principle, due to its unique materials and design, it does not require external power to charge incoming particles or to create an electrostatic collection field. The sampler consists of a polarized film wound in a spiral configuration with oppositely polarized film sides positioned 2.25 mm apart. The film and its holder are inserted into a 3D-printed housing cylinder to connect to a pump. The device has an open channel design, creating virtually no pressure drop, which allows for longer sampling times on the same battery charge compared to filter samplers. When REAS was tested in different field environments, the physical collection efficiency ranged from 19 ± 2% in a laboratory environment at 1 L/min to 41 ± 0.1% in residence at 0.1 L/min. When REAS was used to capture culturable bacteria and fungi over a 24-hr period, the concentrations determined by REAS were not different from those determined by an Institute of Medicine sampler (IOM, SKC, Inc.). The concentrations determined by both samplers were lower than those measured by a SAS Super 180 Sampler (SAS, Bioscience International), except for outdoor fungi. However, the SAS was used as a grab sampler to avoid overloading or desiccating the plates, while both REAS and IOM continuously sampled for 24 hrs. Further studies will explore improvements to the REAS sample elution protocols.

Mori Ramulus Inhibits Pancreatic β-Cell Apoptosis and Prevents Insulin Resistance by Restoring Hepatic Mitochondrial Function

Antioxidants · 2021-06-03 · 5 citations

Type 2 diabetes mellitus is characterized by insulin resistance and pancreatic beta (β)-cell dysfunction. Accumulating evidence suggests that mitochondrial dysfunction may cause insulin resistance in peripheral tissues. As commercial hypoglycemic drugs have side effects, it is necessary to develop safe and effective natural compound-based hypoglycemic treatments. This study aimed to investigate the hypoglycemic effects of Mori Ramulus ethanol extract (ME) in a high-fat diet (HFD)-induced diabetes mouse model to decipher the underlying mechanisms focusing on apoptosis and mitochondrial function. ME significantly decreased tunicamycin-induced apoptotic cell death and increased insulin secretion following glucose stimulation in NIT-1 pancreatic β-cells. Tunicamycin-exposed NIT-1 pancreatic β-cells showed elevated reactive oxygen species levels and reduced mitochondrial membrane potential, which were reversed by ME treatment. ME inhibited the tunicamycin-induced apoptosis cascade in tunicamycin-exposed NIT-1 pancreatic β-cells. In HFD diabetic mice, the serum-free fatty acid and insulin levels decreased following a 15-week ME administration. Glucose and insulin tolerance tests showed that ME improved insulin sensitivity. Moreover, ME ameliorated pancreatic β-cell mass loss in diabetic mice. Finally, ME-treated HFD-fed mice showed improved hepatic mitochondrial function resulting in insulin sensitivity in target tissues. Thus, ME provides protection against pancreatic β-cell apoptosis and prevents insulin resistance by improving mitochondrial function.