Puff Bar, one of the latest designs of e-cigarettes, heats a mixture of liquid using a battery-powered coil at certain temperatures to emit aerosol. This study presents a mass-based characterization of emissions from seven flavors of Puff Bar devices by aerosolizing with three puff topographies [(puff volume: 55 < 65 < 75-mL) within 4-seconds at 30-seconds interval]. We evaluated the effects of puff topographies on heating temperatures; characterized particles using a cascade impactor; and measured volatile carbonyl compounds (VCCs). Modeled dosimetry and calculated mass median aerodynamic diameters (MMADs) were used to estimate regional, total respiratory deposition of the inhaled aerosol and exhaled fractions that could pose secondhand exposure risk. Temperatures of Puff Bar e-liquids increased with increasing puff volumes: 55 mL (116.6 C), 65 mL (128.3 C), and 75 mL (168.9 C). Flavor types significantly influenced MMADs, total mass of particles, and VCCs (g/puff: 2.15-2.30) in Puff Bar emissions (p < 0.05). Increasing puff volume (mL:55 < 65 < 75) significantly increased total mass (mg/puff: 4.6 < 5.6 < 6.2) of particles without substantially changing MMADs (1m:1.02 0.99 0.98). Aerosol emissions were estimated to deposit in the pulmonary region of e-cigarette user (4144%), which could have toxicological importance. More than 2/3 (6777%) of inhaled particles were estimated to be exhaled by users, which could affect bystanders. The VCCs measured contained carcinogensformaldehyde (29.6%) and acetaldehyde (16.4%)as well as respiratory irritants: acetone (23.9%), isovaleraldehyde (14.5%), and acrolein (4.9%). As Puff Bar emissions contain respirable particles and harmful chemicals, efforts should be made to minimize exposures, especially in indoor settings where people (including vulnerable populations) spend most of their life-time. Copyright 2023 American Association for Aerosol Research. , This work was authored as part of the Contributor's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 USC. 105, no copyright protection is available for such works under US Law.

Puff Bar™, one of the latest designs of e-cigarettes, heats a mixture of liquid using a battery-powered coil at certain temperatures to emit aerosol. This study presents a mass-based characterization of emissions from seven flavors of Puff Bar™ devices by aerosolizing with three puff topographies [(puff volume: 55 < 65 < 75-mL) within 4-seconds at 30-seconds interval]. We evaluated the effects of puff topographies on heating temperatures; characterized particles using a cascade impactor; and measured volatile carbonyl compounds (VCCs). Modeled dosimetry and calculated mass median aerodynamic diameters (MMADs) were used to estimate regional, total respiratory deposition of the inhaled aerosol and exhaled fractions that could pose secondhand exposure risk. Temperatures of Puff Bar™ e-liquids increased with increasing puff volumes: 55 mL (116.6 °C), 65 mL (128.3 °C), and 75 mL (168.9 °C). Flavor types significantly influenced MMADs, total mass of particles, and VCCs (µg/puff: 2.15-2.30) in Puff Bar™ emissions (p < 0.05). Increasing puff volume (mL:55 < 65 < 75) significantly increased total mass (mg/puff: 4.6 < 5.6 < 6.2) of particles without substantially changing MMADs (∼1µm:1.02 ∼ 0.99 ∼ 0.98). Aerosol emissions were estimated to deposit in the pulmonary region of e-cigarette user (41–44%), which could have toxicological importance. More than 2/3 (67–77%) of inhaled particles were estimated to be exhaled by users, which could affect bystanders. The VCCs measured contained carcinogens—formaldehyde (29.6%) and acetaldehyde (16.4%)—as well as respiratory irritants: acetone (23.9%), isovaleraldehyde (14.5%), and acrolein (4.9%). As Puff Bar™ emissions contain respirable particles and harmful chemicals, efforts should be made to minimize exposures, especially in indoor settings where people (including vulnerable populations) spend most of their life-time. Copyright © 2023 American Association for Aerosol Research. ©, This work was authored as part of the Contributor's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 USC. 105, no copyright protection is available for such works under US Law.

Developmental delays, disorders, or disabilities (DDs) manifest in infancy and childhood and can limit a person's function throughout life* (1-3). To guide strategies to optimize health for U.S. children with DDs, CDC analyzed data from 44,299 participants in the 2014-2018 National Health Interview Survey (NHIS). Parents reported on 10 DDs,(†) functional abilities, health needs, and use of services. Among the approximately one in six (17.3%) U.S. children and adolescents aged 3-17 years (hereafter children) with one or more DDs, 5.7% had limited ability to move or play, 4.7% needed help with personal care, 4.6% needed special equipment, and 2.4% received home health care, compared with ≤1% for each of these measures among children without DDs. Children with DDs were two to seven times as likely as those without DDs to have taken prescription medication for ≥3 months (41.6% versus 8.4%), seen a mental health professional (30.6% versus 4.5%), a medical specialist (26.0% versus 12.4%), or a special therapist, such as a physical, occupational, or speech therapist, (25.0% versus 4.5%) during the past year, and 18 times as likely to have received special education or early intervention services (EIS) (41.9% versus 2.4%). These percentages varied by type of disability and by sociodemographic subgroup. DDs are common, and children with DDs often need substantial health care and services. Policies and programs that promote early identification of children with developmental delays and facilitate increased access to intervention services can improve health and reduce the need for services later in life.(§) Sociodemographic inequities merit further investigation to guide public health action and ensure early and equitable access to needed care and services.

The current fourth generation ("pod-style") electronic cigarette, or vaping, products (EVPs) heat a liquid ("e-liquid") contained in a reservoir ("pod") using a battery-powered coil to deliver aerosol into the lungs. A portion of inhaled EVP aerosol is estimated as exhaled, which can present a potential secondhand exposure risk to bystanders. The effects of modifiable factors using either a prefilled disposable or refillable pod-style EVPs on aerosol particle size distribution (PSD) and its respiratory deposition are poorly understood. In this study, the influence of up to six puff profiles (55-, 65-, and 75-ml puff volumes per 6.5 and 7.5 W EVP power settings) on PSD was evaluated using a popular pod-style EVP (JUUL(®) brand) and a cascade impactor. JUUL(®) brand EVPs were used to aerosolize the manufacturers' e-liquids in their disposable pods and laboratory prepared "reference e-liquid" (without flavorings or nicotine) in refillable pods. The modeled dosimetry and calculated aerosol mass median aerodynamic diameters (MMADs) were used to estimate regional respiratory deposition. From these results, exhaled fraction of EVP aerosols was calculated as a surrogate of the secondhand exposure potential. Overall, MMADs did not differ among puff profiles, except for 55- and 75-ml volumes at 7.5 W (p < 0.05). For the reference e-liquid, MMADs ranged from 1.02 to 1.23 μm and dosimetry calculations predicted that particles would deposit in the head region (36-41%), in the trachea-bronchial (TB) region (19-21%), and in the pulmonary region (40-43%). For commercial JUUL(®) e-liquids, MMADs ranged from 0.92 to 1.67 μm and modeling predicted that more particles would deposit in the head region (35-52%) and in the pulmonary region (30-42%). Overall, 30-40% of the particles aerosolized by a pod-style EVP were estimated to deposit in the pulmonary region and 50-70% of the inhaled EVP aerosols could be exhaled; the latter could present an inhalational hazard to bystanders in indoor occupational settings. More research is needed to understand the influence of other modifiable factors on PSD and exposure potential.

Human genital Chlamydia infection is a major public health concern due to the serious reproductive system complications. Chlamydia binds several receptor tyrosine kinases (RTKs) on host cells, including the epidermal growth factor receptor (EGFR) and activates cellular signaling cascades for host invasion, cytoskeletal remodeling, optimal inclusion development, and induction of pathogenic epithelial-mesenchyme transition (EMT). Chlamydia also upregulates TGF-beta expression whose signaling pathway synergizes with the EGFR cascade, but its role in infectivity, inclusions and EMT induction is unknown. We hypothesized that the EGFR and TGF-beta signaling pathways cooperate during chlamydial infection for optimal inclusion development and stable EMT induction. The results revealed that Chlamydia upregulated TGF-beta expression as early as 6 h post-infection of epithelial cells and stimulated both the EGFR and TGF-beta signaling pathways. Inhibition of either the EGFR or TGF-betaR1 signaling substantially reduced inclusions development; however, the combined inhibition of both EGFR and TGF-betaR1 signaling reduced inclusions by over 90% and prevented EMT induction. Importantly, EGFR inhibition suppressed TGF-beta expression, and an inhibitory thrombospondin-1 (Tsp1)-based peptide inhibited chlamydia-induced EMT, revealing a major source of active TGF-betaduring infection. Finally, TGF-betaR signaling inhibition suppressed the expression of transforming acidic coiled-coil protein-3 (TACC3) that stabilizes EGFR signaling, suggesting a reciprocal regulation between TGF-beta and EGFR signaling during chlamydial infection. Thus, RTK-mediated host invasion by chlamydia upregulated TGF-beta expression and signaling, which cooperated with other cellular signaling cascades and cytoskeletal remodeling to support optimal inclusion development and EMT induction. The finding may provide new targets for chlamydial disease biomarkers and prevention.

Nipah virus is a highly lethal zoonotic pathogen found in Southeast Asia that has caused human encephalitis outbreaks with 40%-70% mortality. NiV encodes its own RNA-dependent RNA polymerase within the large protein, L. Efficient polymerase activity requires the phosphoprotein, P, which tethers L to its template, the viral nucleocapsid. P is a multifunctional protein with modular domains. The central P multimerization domain is composed of a long, tetrameric coiled coil. We investigated the importance of structural features found in this domain for polymerase function using a newly constructed NiV bicistronic minigenome assay. We identified a conserved basic patch and central kink in the coiled coil that are important for polymerase function, with R555 being absolutely essential. This basic patch and central kink are conserved in the related human pathogens measles and mumps viruses, suggesting that this mechanism may be conserved.

Exposures to diacetyl, a primary ingredient of butter flavoring, have been shown to cause respiratory disease among workers who mix flavorings. This study focused on evaluating ventilation controls designed to reduce emissions from the flavor mixing tanks, the major source of diacetyl in the plants. Five exhaust hood configurations were evaluated in the laboratory: standard hinged lid-opened, standard hinged lid-closed, hinged lid-slotted, dome with 38-mm gap, and dome with 114-mm gap. Tracer gas tests were performed to evaluate quantitative capture efficiency for each hood. A perforated copper coil was used to simulate an area source within the 1.2-meter diameter mixing tank. Capture efficiencies were measured at four hood exhaust flow rates (2.83, 5.66, 11.3, and 17.0 cubic meters per minute) and three cross draft velocities (0, 30, and 60 meters per minute). All hoods evaluated performed well with capture efficiencies above 90% for most combinations of exhaust volume and cross drafts. The standard hinged lid was the least expensive to manufacture and had the best average capture efficiency (over 99%) in the closed configuration for all exhaust flow rates and cross drafts. The hinged lid-slotted hood had some of the lowest capture efficiencies at the low exhaust flow rates compared to the other hood designs. The standard hinged lid performed well, even in the open position, and it provided a flexible approach to controlling emissions from mixing tanks. The dome hood gave results comparable to the standard hinged lid but it is more expensive to manufacture. The results of the study indicate that emissions from mixing tanks used in the production of flavorings can be controlled using simple inexpensive exhaust hoods.

Conducting regular assessments of each miner’s knowledge and skills with respect to lifelines should be a key component of miner safety training. The better prepared miners are to escape from the mine quickly, the better their ultimate chances of survival. Recent NIOSH research reveals several ways miners can be helped to improve their recognition of lifeline tactile signals. | Lifelines with various tactile signals have been required by federal regulation 30 CFR Part 74.380 since 2009. There are now five types of tactile signals on lifelines: directional cones (which indicate the direction to go outby), a coil to indicate a refuge chamber, two sets of double cones to indicate a self-contained, self-rescuer (SCSR) cache, two directional cones in a row to indicate a branch line, and a ball to indicate a personnel door. These signals were instituted to provide an additional navigational tool to help miners escape in the event of an emergency. | Despite the implementation of this new safety feature, miners may not always remember what the signals mean, especially in an emergency situation. It is important miners are able to identify the signals reliably because it could save them a significant amount of time while trying to escape. In addition to telling them which direction is outby, the signals could save them time because, instead of following a branch line to find out where it leads, miners can feel the signal at the beginning of the branch line and immediately know what is available at the end. They can also immediately identify when a line is a branch line as opposed to the main lifeline which leads them directly out of the mine.

Due to the fibrous shape and durability of multi-walled carbon nanotubes (MWCNT), concerns regarding their potential for producing environmental and human health risks, including carcinogenesis, have been raised. This study sought to investigate how previously identified lung cancer prognostic biomarkers and the related cancer signaling pathways are affected in the mouse lung following pharyngeal aspiration of well-dispersed MWCNT. A total of 63 identified lung cancer prognostic biomarker genes and major signaling biomarker genes were analyzed in mouse lungs (n=80) exposed to 0, 10, 20, 40, or 80mug of MWCNT by pharyngeal aspiration at 7 and 56days post-exposure using quantitative PCR assays. At 7 and 56days post-exposure, a set of 7 genes and a set of 11 genes, respectively, showed differential expression in the lungs of mice exposed to MWCNT vs. the control group. Additionally, these significant genes could separate the control group from the treated group over the time series in a hierarchical gene clustering analysis. Furthermore, 4 genes from these two sets of significant genes, coiled-coil domain containing-99 (Ccdc99), muscle segment homeobox gene-2 (Msx2), nitric oxide synthase-2 (Nos2), and wingless-type inhibitory factor-1 (Wif1), showed significant mRNA expression perturbations at both time points. It was also found that the expression changes of these 4 overlapping genes at 7days post-exposure were attenuated at 56days post-exposure. Ingenuity Pathway Analysis (IPA) found that several carcinogenic-related signaling pathways and carcinogenesis itself were associated with both the 7 and 11 gene signatures. Taken together, this study identifies that MWCNT exposure affects a subset of lung cancer biomarkers in mouse lungs.

Two independent modifications were made to one of two identical side-by-side filter banks for a large air-handler: ( 1) new filter holders, intended to provide a better seal and ( 2) ultraviolet germicidal irradiation (UVGI) lamps, intended to control microbiological growth. Total system efficiency testing with optical particle counters was performed to determine the effectiveness of the new filter holders. The efficacy of the UVGI lamps was determined through biological surface and air sampling. Results indicated that the side with the new filter holders was about 3.4% more efficient per year during the 22-month sampling period, whereas the coil chamber with the UVGI lamps had less biological contamination than the corresponding control chamber for over 75% of the sampling days.