Prevalence, duration of exposure and predicting factors for snus use among young Finnish men: a cross-sectional study

ObjectiveThe health hazards of tobacco products depend on the level of exposure, but little is known about the characteristics of snus use. The aim of this study was to investigate the duration of daily exposure to snus among occasional and daily users and its associated predictive factors among young Finnish men.DesignCross-sectional questionnaire study.SettingThree out of 16 Finnish Defence Forces units.Participants1280 young Finnish male conscripts starting their military service in 2016 chosen by simple random sampling.Primary and secondary measuresThe prevalence, duration of use and the amount of daily usage of snus and cigarettes were investigated. The attitudes towards perceived harmfulness of snus and the predictive factors affecting the total time of snus consumption were examined.ResultsAlmost a fifth (19.5%) of the conscripts reported daily snus use, and a further 16% reported occasional use. Daily snus use was associated with an earlier starting age, longer duration of use and higher daily exposure time compared with occasional use. On average, daily snus users consumed 10 portions and occasional users three portions per day (p<0.001). The daily total exposure time for daily users was 372 min (95% CI 344 to 401) and for occasional users 139 min (95% CI 106 to 171). Respondents with an upper secondary education had significantly less daily total exposure than those with basic comprehensive education (p=0.036). Perceptions of snus as a harmful substance resulted in a significantly lower duration of exposure.ConclusionSnus use was very common among young Finnish men. High snus exposure duration was associated with an earlier starting age, a longer history of use and a careless attitude to its health hazards. A higher education level was a protective factor for total exposure time. Studies of the long-term health effects and dependency profile of snus use are needed.

External auditory exostoses in wind-dependent water sports participants: German wind- and kitesurfers

Purpose Cold water and wind are known to cause exostoses of the external auditory canal. Different prevalences in different sports have been described in the literature. The aim of this study was to investigate the prevalence of external auditory exostosis (EAE) and EAE severity in coastal German wind- and kitesurfers who are exposed to cold water and strong winds. Furthermore, influencing factors such as the total exposure time and frequency of activity as well as the correlations between symptoms and the severity of EAE were investigated. Methods In this retrospective cross-sectional study, German non-professional wind- and kitesurfers along the North and Baltic Sea coasts were recruited between September 2020 and November 2020. Each participant was interviewed about exposure time and otological symptoms and underwent bilateral video otoscopic examination to determine EAE severity. Results A total of 241 ears from 130 subjects were analysed. The prevalence of EAE was 75.1%. In 19.9% of the participants, severe EAE was found. Exposure time and the frequency of activity had significant effects on the severity of EAE. Compared to surfers, EAE growth seems to progress faster in wind- and kitesurfers. The number of symptoms requiring medical treatment increased when two-thirds of the external auditory canal was obstructed. Conclusion The prevalence of EAE in wind- and kitesurfers is high. Total exposure time and the frequency of activity influence EAE growth. EAE growth occurs faster in wind- and kitesurfers than in surfers. The additional influence of wind and the evaporative cooling of the EAC are thought to be responsible. The results of this study should increase awareness of the dynamics of EAE among ENT specialists and improve patient counselling.

Optimization of the parameters of a laser induced breakdown spectrometer (LIBS) using probabilistic-deterministic design of experiment

A method for optimizing the settings of a LIBS device aimed at achieving the maximum intensity of analytical lines of the analyte of constant composition is considered using probabilistic-deterministic design of experiments (PDDE). A mixture of Cr, Mn, Fe, Co, and Ni oxides homogenized and diluted by fusion with a lead-phosphate mixture is used as an analyte. It is shown that data of mathematical processing of 25 spectra by the PDDE method can be used to develop mathematical models which relate the line intensity with the energy of the laser pumping lamp, the lag time of the first and second Q-switches, the time delay of the exposure onset, and the total exposure time. The use of the geometric mean and mathematical model in the form of the product of the partial dependences leads to a good correlation between the calculated and experimental values of the intensity for all the considered spectral lines. The simulation results presented for 16 analytical lines of Cr, Mn, Co, and Ni illustrate the applicability of the method under consideration. The experimentally achieved maximum intensities of analytical lines in the matrix of lead-phosphate glass differ from those calculated using the obtained models by 7 – 12 %. There is a linear correlation between the experimental and calculated values of the intensity at R2 = 0.99 and an inclination angle close to 45°. The spectra recorded during the experiment can be used for optimization of other parameters, e.g., the signal-to-noise ratio. The simplicity of calculations and relatively small number of tests in the optimization experiment make the PDDE a promising method for optimizing the LIBS parameters.

Experimental Study on the Coating Removing Characteristics of High-Pressure Water Jet by Micro Jet Flow

In this paper, coating removal characteristics of water jet by micro jet flow affected by cleaning parameters is analyzed. Numerical simulation of fluid field calculates the velocity and pressure distribution of a water jet impinging on a rigid wall, which is used for design experiments of coating removal affected by jet pressure, traversal speed, and repeated impacting times. The removal width is used as a measure of water jet coating removal capability. Experiment results show that the coating removal width is constant, independent with traversal speed or repeated times when total exposure time of waterjet impingement is fixed. According to results of coating removal by a linear moving water jet, this study also analyzes characteristics of coating removal by rotating jet disc, especially residual coating affected by rotational and moving speed of the cleaning disc. The research is helpful to improve the coating removal efficiency of cleaning disc devices.

Vaccine Prioritisation Using Bluetooth Exposure Notification Apps

After vaccinating health care workers and vulnerable groups against COVID-19, authorities will need to decide how to vaccinate everyone else. Prioritising individuals with more contacts can be disproportionately effective, in theory, but identifying these individuals is difficult. Here we show that the technology underlying Bluetooth exposure notification applications, such as used for digital contact tracing, can be leveraged to prioritise vaccination based on individual contact data. Our approach is based on the insight that these apps also act as local sensing devices measuring each user's total exposure time to other users, thereby enabling the implementation of a previously impossible strategy that prioritises potential super-spreaders. Furthermore, by generalising percolation theory and introducing a novel measure of vaccination efficiency, we demonstrate that this ``hot-spotting" strategy can achieve herd immunity with up to half as many vaccines as a non-targeted strategy, and is attractive even for relatively low rates of app usage.

Vaccine Prioritisation Using Bluetooth Exposure Notification Apps

After vaccinating health care workers and vulnerable groups against COVID-19, authorities will need to decide how to vaccinate everyone else. Prioritising individuals with more contacts can be disproportionately effective, in theory, but identifying these individuals is difficult. Here we show that the technology underlying Bluetooth exposure notification applications, such as used for digital contact tracing, can be leveraged to prioritise vaccination based on individual contact data. Our approach is based on the insight that these apps also act as local sensing devices measuring each user’s total exposure time to other users, thereby enabling the implementation of a previously impossible strategy that prioritises potential super-spreaders. Furthermore, by generalising percolation theory and introducing a novel measure of vaccination efficiency, we demonstrate that this “hot-spotting” strategy can achieve herd immunity with up to half as many vaccines as a non-targeted strategy, and is attractive even for relatively low rates of app usage.

Colorimetric changes of waterbased flexographic ink printed on hemp-based papers exposed to artificial ageing

The objective of the research was to investigate colorimetric changes of the waterbased flexographic ink printed on hemp-based papers subjected to artificial ageing. Three types of commercially available hemp office papers were used as printing substrate and by Esiproof instrument were printed manually in full tone with process waterbased flexographic inks. Both, papers and prints were exposed to artificial ageing in the Suntest XLS+ test chamber according ASTM D 6789-2 standard. The L∗, a∗, b∗ colour coordinates were measured and ΔE00 colour difference was calculated for different stages of light exposure in order to determine the change from the original color value. In total exposure time was 96 h. The results have shown how the paper optical stability is dependent upon manufacturing process and that bleached hemp fibers provides better optical stability of papers than unbleached hemp fibers. Further, stability of prints made on hemp-based papers is for the most part defined by ink color, while the impact of the printing substrate is less pronounced. Generally, it was noticed how the most stable among prints were prints covered with the black ink, while prints with the yellow ink had the greatest changes in color under the influence of light.

The InSight Mars lander’s meteor search

&lt;p&gt;The InSight lander (Banerdt et al. 2020) on Mars is equipped with two cameras capable of sky imaging both of which have been used opportunistically to search for meteors. The rate of occurrence of Martian meteors has not been directly measured and initial reports of an imaged meteor by Selsis et al. 2005 were likely incorrect (Domokos et al. 2007). The meteor search is part of the investigation into the flux of impactors at Mars (Daubar et al. 2018).&lt;/p&gt;&lt;p&gt;The InSight cameras have been described by Maki et al. (2018). The Instrument Deployment Camera (IDC) can be aimed by a robotic arm and has a 45-degree square field of view (FOV). However, this camera was typically unavailable, and has only been used twice. The Instrument Context Camera (ICC) has a 120-degree fisheye FOV. It is aimed downward, but sees a broad section of the southern sky to around 20-degrees elevation angle.&lt;/p&gt;&lt;p&gt;&lt;img src=&quot;https://contentmanager.copernicus.org/fileStorageProxy.php?f=gnp.2dbe9847c2fe52309692951/sdaolpUECMynit/0202CSPE&amp;app=m&amp;a=0&amp;c=de01f9fb2b7b64c855d9ebeb43a5dc97&amp;ct=x&amp;pn=gnp.elif&quot; alt=&quot;&quot;&gt;&lt;/p&gt;&lt;p&gt;IDC images are shown in Fig. 1. They were aimed to the southwest at an elevation of about 35 degrees, and on sols 126 and 176 (5 April and 27 May 2019), four 5-minute exposures were acquired. Stars are visible in the images, and will be used to determine the sensitivity. Many cosmic rays were seen (e.g., Fig. 2)&amp;#8212;long ones can be mistaken for meteors, but they have a distinctive morphology with a narrow end and a diffuse end due to the charge diffusion process after the charged particles pass through the detector (Fisher-Levine and Nomerotski, 2015). Despite the Sun being 60 degrees down, diffuse sky brightness was visible (Banfield et al. 2020). No meteors were detected.&lt;/p&gt;&lt;p&gt;&lt;img src=&quot;https://contentmanager.copernicus.org/fileStorageProxy.php?f=gnp.06223757c2fe57409692951/sdaolpUECMynit/0202CSPE&amp;app=m&amp;a=0&amp;c=833d2d4c552dd6bf74df483e42e002eb&amp;ct=x&amp;pn=gnp.elif&quot; alt=&quot;&quot;&gt;&lt;/p&gt;&lt;p&gt;ICC images are shown in Fig. 3&amp;#8212;about 75% of the images do not include sky. On 25 sols from 254 to 432 (15 August 2019 to 6 February 2020), the ICC acquired four, 5-minute exposures. No meteors were seen.&lt;/p&gt;&lt;p&gt;We will present an analysis of the results and their implication for the meteor rate at Mars. While no meteors were seen, the upper limit is likely to be constraining. Total exposure time is 540 minutes, using cameras more sensitive than the limiting exposures of Domokos et al. (2007) and with wider FOVs. However, the complex geometry and the time variable atmospheric dust extinction will be considered.&lt;/p&gt;&lt;p&gt;&lt;img src=&quot;https://contentmanager.copernicus.org/fileStorageProxy.php?f=gnp.2afc6477c2fe56709692951/sdaolpUECMynit/0202CSPE&amp;app=m&amp;a=0&amp;c=bb21c68541a1d2ace1ff02728cb9e0a6&amp;ct=x&amp;pn=gnp.elif&quot; alt=&quot;&quot;&gt;&lt;/p&gt;&lt;p&gt;&lt;strong&gt;References. &lt;/strong&gt;Banerdt et al. 2020. Nature Geoscience, &lt;strong&gt;13&lt;/strong&gt;, 183-189. Banfield et al. 2020. Nature Geoscience, &lt;strong&gt;13&lt;/strong&gt;, 190-198. Daubar et al. 2018. Space Science Rev. &lt;strong&gt;214&lt;/strong&gt;, 132. Domokos et al. 2007. Icarus &lt;strong&gt;191&lt;/strong&gt;, 141-150. Fisher-Levine and Nomerotski 2015. BNL-108381-2015-JA. Maki et al. 2018. Space Sci. Rev. &lt;strong&gt;214&lt;/strong&gt;, 105. Selsis et al. 2005. Nature &lt;strong&gt;435&lt;/strong&gt;, 581.&lt;/p&gt;

Windblast testing of an aircrew helmet: An approach to neck load analysis

Introduction: Modern generation fighter aircraft has expanded the escape envelope for a fighter aircrew. With the ejection occurring at very high airspeeds, windblast is a cause of major injuries and fatalities. Flying helmet, before its induction into operational usage, must be tested in simulated windblast conditions to ensure that they provide adequate safety. Material and Methods: Windblast tests were conducted on a newly designed/procured helmet in a standard windblast test facility as per Mil Std MIL-V-29591/1. A large instrumented Hybrid III male dummy was used for the tests. The test conditions were: Wind speed 600 ± 60 KEAS, rise time of 125 ± 20 ms, time at peak wind velocity of 300 ± 50 ms, and total exposure time of ≥3 s. Structural integrity, retention with the headform, and recorded neck loads were assessed for interpretation of test results. Results: Helmets could withstand the windblast conditions without any significant structural failures and were retained with the headform during the entire duration of test conditions. However, analysis of the neck loads resulted in a significant dilemma in aeromedical decision-making, there being no laid down criteria in the Mil Specification. The neck tension forces were more than the acceptable limits and found to have the potential for significant neck injuries as per the Injury Assessment Reference Values specified in AGARD-AR-330 specifically in the tests where blast was head on and outer visor in up configuration; however, these values were within the acceptable limits as per the other proposed criteria. Similarly, analysis of the neck tension extension combined effects revealed conflicting outcomes for Nij performance limits specified in various standards. This paper discusses the critical analysis of neck loads vis-à-vis the neck injury criteria to understand the neck loads generated during windblast conditions and its implication on aircrew safety. Conclusion: Neck loads assessment is critical in predicting aircrew safety during windblast testing. In the absence of a clearly defined criteria in the Mil Specification, critical ananlysis of neck loads vis-à-vis recommended standards in scientific literature be done to make meaningful conclusion.

A Novel Universal Endovascular Robot for Peripheral Arterial Stent–Assisted Angioplasty: Initial Experimental Results

Background: The bottleneck of the development of endovascular interventional robot is that it cannot fully adapt to commercialized endovascular devices, such as guidewires, catheters, and stents, and cannot complete the entire procedure of endovascular treatment, for instance, stent implantation. The purpose of this study is to evaluate whether the novel universal endovascular interventional robot can adapt to different commercialized endovascular devices and accomplish the entire procedure of endovascular treatment of peripheral vascular disease. Methods and Material: The novel universal endovascular interventional robot consists of 2 components: a master surgeon console and a robotic platform with 4 manipulators. An adult pig was served as the experimental animal. Bilateral iliac artery stent implantation was performed on the pig by the endovascular interventional robot using commercialized guidewires, catheters, and stent delivery systems. Results: The novel universal endovascular interventional robot can adapt to commercialized endovascular devices, and most interventional procedures, such as insertion, withdrawal, and rotating, can be done through remote control. By coordinating multiple manipulators, complex actions such as superselection, crossing action, or implantation of self-expanding bare stent can be realized. The entire procedure took about 50 minutes, and the total exposure time of the surgeon was less than 1 minute. Postoperative angiography showed that the position of the stent grafts was accurate. The procedure was stable without any stent or surgical-related complications. Conclusion: The novel universal endovascular interventional robot can realize peripheral arterial stent-assisted angioplasty with commercialized devices. Through the design improvement, the problem related to stent implantation is solved, and the remote operation is realized throughout the endovascular procedure.