Mass change tracking approach as collection guidelines for aerosol and vapor samples released during e-cigarette smoking

2016 ◽  
Vol 8 (10) ◽  
pp. 2305-2311 ◽  
Author(s):  
Ki-Hyun Kim
Keyword(s):  
Cigarette Smoking ◽  
Flow Rate ◽  
Electronic Cigarettes ◽  
Mass Change ◽  
Solution Composition ◽  
Charge Condition ◽  
Battery Charge ◽  
Methodological Basis ◽  
Sampling Flow Rate ◽  
Sampling Flow

There are growing concerns about the lack of a methodological basis for the quantification of various pollutants from electronic cigarettes (ECs). In this study we use a mass change tracking (MCT) approach to explore the potent roles of key sampling variables in the quantitation of EC-produced aerosols/vapors: the sampling flow rate (or puff velocity), battery charge condition, and solution composition.

scholarly journals Ozone removal efficiency of the KI-denuder in the carbonyl sampling

2019 ◽  
Vol 2 (5) ◽  
pp. 153-160
Author(s):  
Huy Huu Duong ◽  
Vui Thi Kim Tran ◽  
Chuong Thanh Nguyen ◽  
Hien Thi To
Keyword(s):  
Removal Efficiency ◽  
Flow Rate ◽  
Carbonyl Compounds ◽  
Climatic Conditions ◽  
Ho Chi Minh City ◽  
High Humidity ◽  
Optimum Parameters ◽  
Sampling Flow Rate ◽  
High Humidity Condition ◽  
Sampling Flow

In the carbonyl sampling of 2, 4- dinitrophenylhydrazine (DNPH) impregnated cartridge, the ozone removal was necessary because ozone reacted with the DNPH derivatives. A commercial ozone scrubber was usually used to remove O3. However, high humidity leaded to carbonyl compounds being trapped on the ozone scrubber before passing through the DNPH cartridge. The purpose of this study was to assess the ozone removal by KI-denuder under the climatic conditions of Ho Chi Minh City. Several parameters including air sampling flow rate and denuder length were optimized to achieve the highest removal efficiency. The optimum parameters of the KI denuder were the sampling flow rate of less than 1 L/min, and the denuder length of 20 cm. The effect of the initial O3 concentration on the removal efficiency was also investigated. Finally, the ozone removal efficiency of KI-denuder was compared to that of ozone scrubber when two devices were applied for the carbonyl sampling during field measurement. The results show that KI-denuder could be used to replace the ozone scrubber with high removal efficiency, particularly in high humidity condition. In conclusion, KI-denuder was effective, simple, easy to use and cheap. Therefore, it was encouraged to use in carbonyl sampling.

Respiratory Gas Analysers

2011 ◽  
Author(s):  
Patrick Magee ◽  
Mark Tooley
Keyword(s):  
Flow Rate ◽  
Delay Time ◽  
Physical Principle ◽  
Breathing System ◽  
Sampling Tube ◽  
Gas Concentration ◽  
Square Wave ◽  
Gas Sampling ◽  
Sampling Flow Rate ◽  
Sampling Flow

The purpose of respiratory gas analysis during anaesthesia is to identify and measure the concentrations, on a breath by breath basis, of the individual gases and vapours in use. It may also be useful as a guide to cardiac function or to identify trace contaminant gases. Different techniques use different physicochemical properties of the gas or vapour. An understanding of the physical principle underlying each method is necessary in order to recognise the value and limitations of each. In terms of the device’s ability to respond on a breath by breath basis, there are two important components: the time taken for the gas to be sampled from the anaesthetic machine or breathing system, the delay time; then there is the time taken for the device to measure the gas concentration, the response time. This is depicted in Figure 16.1. Most of the delay occurs in the delay time or transit time and can be reduced either by analysing the gas sample close to the airway, or by using as short and thin a sampling tube and as high a sampling flow rate to the analyser as possible [Chan et al. 2003]; the sampling flow rate is usually of the order of 100 to 200 ml min−1. If minimal fresh gas flow rates are being used in a circle anaesthetic breathing system and the sampled gas is not returned to the breathing system, then a high gas sampling rate could represent a significant gas leak. Figure 16.1 shows a sigmoid curve of recorded gas concentration change in response to a square wave input change. The response of a gas analyser is often expressed as the time taken to produce a 90–95% response to a step or square wave input change. A square wave change in gas concentration can be produced by moving a gas sampling tube rapidly into and out of a gas stream, by bursting a small balloon within a sampling volume containing a gas sample, or by switching a shutter to a gas sample volume using a solenoid valve. An important part of the use of gas analysers is zeroing and calibration since they are all prone to drift in both zero and gain.

scholarly journals Development of an efficient viral aerosol collector for higher sampling flow rate

2017 ◽  
Vol 25 (4) ◽  
pp. 3884-3893 ◽  
Author(s):  
Xiao-Ting Lin ◽  
Nai-Yun Hsu ◽  
Jen-Ren Wang ◽  
Nai-Tzu Chen ◽  
Huey-Jen Su ◽  
...  
Keyword(s):  
Flow Rate ◽  
Viral Aerosol ◽  
Sampling Flow Rate ◽  
Sampling Flow

scholarly journals Peak expiratory flow rate among smokers and non-smokers working in Kathmandu Medical College

2020 ◽  
Vol 10 (2) ◽  
pp. 33-35
Author(s):  
Preetu Gurung
Keyword(s):  
Cigarette Smoking ◽  
Peak Expiratory Flow ◽  
Flow Rate ◽  
Peak Expiratory Flow Rate ◽  
Cross Sectional Study ◽  
P Value ◽  
Cross Sectional ◽  
Medical College ◽  
Significant Difference ◽  
Expiratory Flow

Background: Cigarette smoking has remained a popular habit since ages. Most people are well aware of the deleterious effects of cigarette smoking yet continue to give a blind eye which dete­riorates overall public health. The purpose of the present study was to assess Peak Expiratory Flow Rate among smoking and nonsmoking staffs who work in Kathmandu Medical College. Methods: In this comparative cross-sectional study Peak Expiratory Flow Rate was obtained using Mini Wright’s Peak Flow Meter of 108 smokers and 108 nonsmokers in the age group ranging from 25-45 years. Those who never smoked or who have quit smoking for the past 2 years were grouped as nonsmokers and the smokers with history of smoking at least five or more cigarettes per day for at least two years were included in the study for measuring their Peak Expiratory Flow Rate. Data was collected, compiled and analyzed by using Statistical Package of Social Science (SPSS) software version16. Student ‘t’ test was used for group comparison. Results: The Peak Expiratory Flow Rate value was significantly reduced in the smokers (p value< 0.05). Mean Peak Expiratory Flow Rate was reduced with increasing age of the smokers. However, no significant difference was observed in Peak Expiratory Flow Rate with increase in the number of cigarettes smoked (p value> 0.05). Conclusions: In the study Peak Expiratory Flow Rate among smokers (367.13 ± 74.182) was lower than nonsmokers (471.39±60.842), which was statistically significant proving that cigarette smok­ing reduced peak expiratory flow rate.

Individual and synergistic effects of sniffing frequency and flow rate on olfactory bulb activity

2011 ◽  
Vol 106 (6) ◽  
pp. 2813-2824 ◽  
Author(s):  
Emmanuelle Courtiol ◽  
Chloé Hegoburu ◽  
Philippe Litaudon ◽  
Samuel Garcia ◽  
Nicolas Fourcaud-Trocmé ◽  
...  
Keyword(s):  
Olfactory Bulb ◽  
Flow Rate ◽  
Animal Behavior ◽  
Synergistic Effects ◽  
Field Potential ◽  
Sampling Frequency ◽  
Experimental Approaches ◽  
Sampling Flow Rate ◽  
Additional Support ◽  
Local Field Potential Lfp

Is faster or stronger sniffing important for the olfactory system? Odorant molecules are captured by sniffing. The features of sniffing constrain both the temporality and intensity of the input to the olfactory structures. In this context, it is clear that variations in both the sniff frequency and flow rate have a major impact on the activation of olfactory structures. However, the question of how frequency and flow rate individually or synergistically impact bulbar output has not been answered. We have addressed this question using multiple experimental approaches. In double-tracheotomized, anesthetized rats, we recorded both the bulbar local field potential (LFP) and mitral/tufted cells' activities when the sampling flow rate and frequency were controlled independently. We found that a tradeoff between the sampling frequency and the flow rate could maintain olfactory bulb sampling-related rhythmicity and that only an increase in flow rate could induce a faster, odor-evoked response. LFP and sniffing were recorded in awake rats. We found that sampling-related rhythmicity was maintained during high-frequency sniffing. Furthermore, we observed that the covariation between the frequency and flow rate, which was necessary for the tradeoff seen in the anesthetized preparations, also occurred in awake animals. Our study shows that the sampling frequency and flow rate can act either independently or synergistically on bulbar output to shape the neuronal message. The system likely takes advantage of this flexibility to adapt sniffing strategies to animal behavior. Our study provides additional support for the idea that sniffing and olfaction function in an integrated manner.

scholarly journals In Vitro Models, Standards, and Experimental Methods for Tobacco Products

2019 ◽  
Vol 30 (1) ◽  
pp. 16-21 ◽  
Author(s):  
T. Aghaloo ◽  
J.J. Kim ◽  
T. Gordon ◽  
H.P. Behrsing
Keyword(s):  
Cigarette Smoking ◽  
Electronic Cigarettes ◽  
Testing Machine ◽  
The United States ◽  
In Vitro Models ◽  
In Vivo Studies ◽  
Tobacco Products ◽  
Direct Exposure

Traditional tobacco products have well-known systemic and local oral effects, including inflammation, vasoconstriction, delayed wound healing, and increased severity of periodontal disease. Specifically in the oral cavity and the lung, cigarette smoking produces cancer, increased infectivity, acute and chronic inflammation, changes in gene expression in epithelial lining cells, and microbiome changes. In recent years, cigarette smoking has greatly decreased in the United States, but the use of new tobacco products has gained tremendous popularity. Without significant knowledge of the oral sequelae of products such as electronic cigarettes, researchers must evaluate current in vitro and in vivo methods to study these agents, as well as develop new tools to adequately study their effects. Some in vitro testing has been performed for electronic cigarettes, including toxicologic models and assays, but these mostly study the effect on the respiratory tract. Recently, direct exposure of the aerosol to in vitro 3-dimensional tissue constructs has been performed, demonstrating changes in cell viability and inflammatory cytokines. For in vivo studies, a universal e-cigarette testing machine or standard vaping regime is needed. A standard research electronic cigarette has recently been developed by the National Institute of Drug Abuse, and other devices delivering aerosols with different nicotine concentrations are becoming available. One of the biggest challenges in this research is keeping up with the new products and the rapidly changing technologies in the industry.

The rise of electronic nicotine delivery systems and the emergence of electronic-cigarette-driven disease

2020 ◽  
Vol 319 (4) ◽  
pp. L585-L595 ◽  
Author(s):  
Kielan Darcy McAlinden ◽  
Mathew Suji Eapen ◽  
Wenying Lu ◽  
Pawan Sharma ◽  
Sukhwinder Singh Sohal
Keyword(s):  
United States ◽  
Cigarette Smoking ◽  
Electronic Cigarettes ◽  
Scientific Evidence ◽  
The United States ◽  
Chronic Obstructive ◽  
Obstructive Pulmonary Disease ◽  
Cellular Processes ◽  
Increased Risk

In 2019, the United States experienced the emergence of the vaping-associated lung injury (VALI) epidemic. Vaping is now known to result in the development and progression of severe lung disease in the young and healthy. Lack of regulation on electronic cigarettes in the United States has resulted in over 2,000 patients and 68 deaths. We examine the clinical representation of VALI and the delve into the scientific evidence of how deadly exposure to electronic cigarettes can be. E-cigarette vapor is shown to affect numerous cellular processes, cellular metabolism, and cause DNA damage (which has implications for cancer). E-cigarette use is associated with a higher risk of developing crippling lung conditions such as chronic obstructive pulmonary disease (COPD), which would develop several years from now, increasing the already existent smoking-related burden. The role of vaping and virus susceptibility is yet to be determined; however, vaping can increase the virulence and inflammatory potential of several lung pathogens and is also linked to an increased risk of pneumonia. As it has emerged for cigarette smoking, great caution should also be given to vaping in relation to SARS-CoV-2 infection and the COVID-19 pandemic. Sadly, e-cigarettes are continually promoted and perceived as a safer alternative to cigarette smoking. E-cigarettes and their modifiable nature are harmful, as the lungs are not designed for the chronic inhalation of e-cigarette vapor. It is of interest that e-cigarettes have been shown to be of no help with smoking cessation. A true danger lies in vaping, which, if ignored, will lead to disastrous future costs.

Effects of Water Chemistry on the Leach Resistance of Synroc C

1983 ◽  
Vol 26 ◽  
Author(s):  
J. L. Woolfrey ◽  
D. M. Levins
Keyword(s):  
Water Chemistry ◽  
Flow Rate ◽  
Volume Ratio ◽  
Chemical Durability ◽  
Borosilicate Glasses ◽  
Solution Composition ◽  
Leach Rate ◽  
Saturation Effects ◽  
Ph Range ◽  
Temperature Surface

ABSTRACTThe chemical durability of SYNROC C has been measured as a function of repository conditions, namely, temperature, surface/volume ratio, groundwater pH and composition. The leach rate of SYNROC C is less dependent on temperature than borosilicate glasses; activation energies range from 15-25 kJ mol-1 compared to 33-74 kJ mol-1 for glass. The rate of release from SYNROC C is very low and independent of solution composition for the solutions studied. There is little variation in leach rate over the pH range 4-9, but at pH 2 the rate is up to 10 times higher. SYNROC C leach rate is independent of flow rate or surface/volume ratio for the mobile waste elements because of the unimportance of solution saturation effects owing to the low concentration of dissolved solids. The differential leach rate decreases rapidly with time because, after initial leaching from grain boundaries and metastable minor phases, the highly insoluble matrix protects the more leachable elements from further attack.

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