A Brief Survey of the Meteorological Aspects of Atmospheric Pollution

1959 ◽  
Vol 40 (4) ◽  
pp. 165-170 ◽  
Author(s):  
H. E. Cramer
Keyword(s):  
Air Pollution ◽  
Atmospheric Pollution ◽  
Empirical Data ◽  
Large Scale ◽  
Current Knowledge ◽  
Diffusion Theory ◽  
Radioactive Fallout ◽  
Small Scale ◽  
Comparable Data ◽  
Intermediate Scale

This article is intended to provide a brief survey of current knowledge of the meteorological aspects of air pollution for meteorologists and others who are not specialists in diffusion. Improved understanding of atmospheric dispersal processes has largely occurred in proportion to the amount of satisfactory empirical data available. The most comprehensive observations refer to small-scale processes, but considerable information on large-scale processes has been obtained in studies of radioactive fallout; comparable data for intermediate-scale processes of the type involved in community air pollution appear to be lacking. Although a satisfactory diffusion theory has not yet emerged, the outlook is encouraging.

scholarly journals Challenges in uncovering non-invasive biomarkers of endometriosis

2020 ◽  
Vol 245 (5) ◽  
pp. 437-447
Author(s):  
Quanah J Hudson ◽  
Alexandra Perricos ◽  
Rene Wenzl ◽  
Iveta Yotova
Keyword(s):  
High Throughput Screening ◽  
Large Scale ◽  
Biomarker Discovery ◽  
Current Knowledge ◽  
Reproductive Age ◽  
Small Scale ◽  
Common Disease ◽  
Sample Collection ◽  
Childbearing Age ◽  
Cohort Selection

Endometriosis affects up to 10% of women of childbearing age, causing symptoms that can include chronic pelvic pain and reduced fertility. The symptoms are not specific to the disease and can be confused with other gynecological conditions or normal menstruation. Currently, the disease can be only definitively diagnosed by laparoscopy, as no clinically accepted biomarker exists. Biomarker discovery can either follow a hypothesis-driven approach selecting targets to be tested based on current knowledge of the disease, or take an unbiased high-throughput screening “omics” approach, such as transcriptomics or proteomics, to identify markers that are unique or elevated in accessible bodily fluids of patients with the disease. Numerous studies have been conducted using these approaches to try and identify endometriosis biomarkers, but variabilities in study design, cohort selection, and analysis, together with the fact that most studies were small-scale, have made independent validation of biomarker candidates difficult. Therefore, efforts are underway to standardize cohort selection, patient data, and sample collection to allow better cross-study comparisons. Large scale multi-center studies using this standardized approach are necessary to validate existing endometriosis biomarker candidates and uncover potential new markers. Given the complexity and heterogeneity of the disease, it is likely that a panel of biomarkers will be necessary to diagnose and categorize endometriosis. Impact statement Endometriosis is a common disease affecting reproductive age women, which is associated with chronic pain and reduced fertility reducing the quality of life of many women. Definitive diagnosis requires invasive laparoscopic surgery creating a high barrier to diagnosis that can delay the onset of treatment significantly. Clinically approved biomarkers of endometriosis are currently lacking, making the discovery and validation of biomarkers that would lead to earlier diagnosis a priority for improving treatment of the disease.

scholarly journals Stratospheric controlled perturbation experiment: a small-scale experiment to improve understanding of the risks of solar geoengineering

2014 ◽  
Vol 372 (2031) ◽  
pp. 20140059 ◽  
Author(s):  
John A. Dykema ◽  
David W. Keith ◽  
James G. Anderson ◽  
Debra Weisenstein
Keyword(s):  
Risk Assessment ◽  
Large Scale ◽  
Current Knowledge ◽  
Stratospheric Ozone ◽  
Full Range ◽  
Stratospheric Aerosol ◽  
Small Scale ◽  
Solar Radiation Management ◽  
Perturbation Experiment ◽  
Radiation Management

Although solar radiation management (SRM) through stratospheric aerosol methods has the potential to mitigate impacts of climate change, our current knowledge of stratospheric processes suggests that these methods may entail significant risks. In addition to the risks associated with current knowledge, the possibility of ‘unknown unknowns’ exists that could significantly alter the risk assessment relative to our current understanding. While laboratory experimentation can improve the current state of knowledge and atmospheric models can assess large-scale climate response, they cannot capture possible unknown chemistry or represent the full range of interactive atmospheric chemical physics. Small-scale, in situ experimentation under well-regulated circumstances can begin to remove some of these uncertainties. This experiment—provisionally titled the stratospheric controlled perturbation experiment—is under development and will only proceed with transparent and predominantly governmental funding and independent risk assessment. We describe the scientific and technical foundation for performing, under external oversight, small-scale experiments to quantify the risks posed by SRM to activation of halogen species and subsequent erosion of stratospheric ozone. The paper's scope includes selection of the measurement platform, relevant aspects of stratospheric meteorology, operational considerations and instrument design and engineering.

Three-dimensional wavelet analysis on turbulent structure of dune wake flow

2015 ◽  
Vol 13 (06) ◽  
pp. 1550045 ◽  
Author(s):  
Yan Zheng ◽  
Akira Rinoshika ◽  
Shun Fujimoto
Keyword(s):  
Coherent Structure ◽  
Large Scale ◽  
Separation Bubble ◽  
Three Dimensional ◽  
Turbulent Structure ◽  
Wake Flow ◽  
Small Scale ◽  
Intermediate Scale ◽  
Numerical Result ◽  
Scale Structures

The three-dimensional (3D) turbulent structure was simulated by large eddy simulation (LES), and then the numerical result was validated by PIV experiment. In order to give a detailed description of dune wake flow, the instantaneous velocity, vorticity, and pressure were decomposed into the large-, intermediate- and relatively small-scale components by 3D wavelet multi-resolution technique. To get a further understanding of coherent structure, the decomposed wavelet components were employed to calculate Q-criterion. It was found that the rollers and horse-shoe structures in the separation bubble were mainly contributed from large-scale structures and it made the most significance to the vorticity concentration. The observations of intermediate-scale horse-shoe structures indicated that the coherent structure was the combined effect of large- and intermediate-scale structures. Besides, from the visualization of 3D streamlines and pressure iso-surfaces, the separation bubble and pressure distribution are found to be dominated by large-scale structure.

scholarly journals Diesel Emissions Increase Air Pollution during the Carnival Festival in Salvador, Bahia-Brazil

2018 ◽  
Author(s):  
Nelzair A. Vianna ◽  
Priscila Novaes ◽  
Nelson Gnoatto ◽  
Simone Miraglia ◽  
Paulo H. Saldiva ◽  
...  
Keyword(s):  
Air Pollution ◽  
Air Quality ◽  
Risk Analysis ◽  
Human Health ◽  
Diesel Fuel ◽  
Atmospheric Pollution ◽  
Large Scale ◽  
Municipal Government ◽  
Public Events ◽  
The City

Atmospheric pollution arising from diesel-powered engines can result in acute and chronic diseases of the respiratory and cardiovascular systems. The annual carnival festival that takes place in the city of Salvador, Bahia-Brazil, is a large-scale event that gathers approximately 2 m revelers and 170,000 workers who accompany dozens of sound-trucks, or trios elétricos, for a period of seven days. These slow-moving sound-trucks run on diesel fuel, constantly exposing those around them to exhaust fumes. The present study aimed to evaluate air quality along the approximately 10km-long carnival parade circuit and determine possible impacts on human health. We applied a three-phase risk analysis strategy from 2007–2009: 1) hazard identification, 2) risk characterization and 3) risk management. Our quantification of atmospheric particulate matter 2.5 (PM2.5) and nitrogen dioxide (NO2) concentrations revealed variable levels of PM2.5 ranging from 19 µg/m3 to 580 µg/m3, with peaks of up to 800 μg/m3 at sound-truck concentration areas. We then assessed the effects of air pollution on human health using ophthalmologic parameters obtained from 28 carnival volunteers, who often presented symptoms of eye irritation. Finally, we established strategies to communicate the study’s objectives and obtained results to the population through media outlets and open discussions with government agencies. According to our risk analysis, carnival sound-trucks represent the main source of atmospheric PM2.5 and NO2 pollution during the annual 7-day carnival festival. As a consequence of our research, the municipal government of Salvador issued an addendum to its carnival legislation mandating organizers to monitor atmospheric pollution, and, subsequently, all large-scale public events. Municipal government authorities have also promoted a shift from petroleum-based diesel fuel to biodiesel, a less-polluting fuel, for all adapted carnival sound-trucks. Our approach, which employed easily accessible and inexpensive methodology, provided substantial scientific evidence to support improvements in the regulation of air quality during large-scale public events held in the city of Salvador.Keywords: environmental

Streamer network critical behavior and lightning initiation

2020 ◽  
Author(s):  
Dmitry Iudin ◽  
Vladimir Rakov ◽  
Artem Syssoev ◽  
Alexey Bulatov
Keyword(s):  
External Field ◽  
Electric Field ◽  
Large Scale ◽  
Spatial Scales ◽  
Potential Difference ◽  
Electrostatic Energy ◽  
Small Scale ◽  
Intermediate Scale ◽  
Scale Field ◽  
Lightning Initiation

<p>In [1] it was established that collective dynamics of charged hydrometeors that involved in turbulent motion play a fundamental role in thundercloud electrostatic energy redistribution and dissipation. The main reservoirs for accumulating electrostatic energy in thunderclouds are i) the large-scale field of the main charged layers that appear due to the large-scale separation of oppositely charged hydrometers, ii) the intermediate-scale field of charged hydrometeors distributed in the turbulent flow, and finally iii) the small-scale field of net and polarization charges on the surface of individual solid and liquid water particles. Since three different spatial scales are involved into the process of electrostatic energy dissipation, we represent the lightning initiation scenario as a sequence of two transitions of discharge activity to progressively larger spatial scales: the first one is from small-scale avalanches to intermediate-scale streamers; and the second one is from streamers to the lightning seed. At the first stage of the proposed scenario, the essentially non-conducting cloud becomes seeded by elevated ion conductivity regions with spatial extent of 0.1 - 1 m and a lifetime of 1 - 10 s. These regions can serve to promote the intermediate electric field enhancements and increase in pre-ionization level that is sufficient for the initiation and development of streamers. Due to the positive the proposed streamer generation mechanism has an important feature: streamers in our scenario are not exponentially rare events, but continuously fill the entire volume. The collective dynamics of such a nearly continuous, volume filling streamer network appears to be very sensitive to both the magnitude of external large-scale electric field and longitudinal extent of the region occupied by the field. Moving in the course of its development along the external field, a positive streamer can get into the negative trails left by other streamers (relay race effect). In this way, the size of the streamer discharge along the external field can grow, providing the emergence of a kind of streamer trees, thereby tapping electrostatic energy from a relatively large cloud volume. Over time, many streamer trees are feeding their current into narrow channels, where the heating occurs (the bottleneck effect). The hot segments of the network can get polarized and grow within its overall channel system even if the ambient field amplitude is much smaller than the critical field of streamer propagation. Successful initiation of lightning also requires that potential difference across the layer occupied by the large-scale electric field makes about three megavolts. The proposed scenario can possibly lead to a paradigm shift in our approaches to the still unsolved mystery of lightning initiation, because it does not require the presence of super-energetic cosmic ray particles, unrealistic potential difference inside the cloud, or unrealistically large hydrometeors.</p><p> </p><p>1. Iudin, D.I., Rakov, V.A., Syssoev, A.A. et al. Formation of decimeter-scale, long-lived elevated ionic conductivity regions in thunderclouds. npj Clim Atmos Sci 2, 46 (2019) doi:10.1038/s41612-019-0102-8.</p>

scholarly journals An Automated Internal Navigation System for the Removal of Fibre Fly in Knitting Industry

2020 ◽  
pp. 275-280
Author(s):  
Sivaranjani P ◽  
Maheswaran S ◽  
Savitha sri N ◽  
Santhosh K V ◽  
Yaswanth M
Keyword(s):  
Air Pollution ◽  
Large Scale ◽  
Small Scale ◽  
Dust Collector ◽  
Paper Briefly ◽  
Knitted Fabrics ◽  
Cotton Yarns ◽  
Knitting Industry ◽  
The Cost ◽  
Small Scale Industries

Knitting industry is one of the flourishing business in India in recent times. This knitting industry provides huge collection of knitted fabrics in different forms and styles. Apart from the fabrics they also provide employment to lot of people. A drastic problem in this industry is the fibre fly generation. These fibre fly are generated in the knitting machine from cotton yarns in different zones of the knitting machine which may be due to friction, yarn breakage and bending of yarns at the needles, sinkers, guides and other regions. They may also be produced due to rotational movement of yarn in the cone unwinding and guiding zone, vibrations during the movement of yarns and friction occurring due to interaction between yarns. At present these fibre fly are removed by using large blowers in large scale industry. These blowers are not affordable in small scale industries due to the cost of blower, power consumption after installation, etc... People exposed to these fibre fly may suffer from serious diseases which may have acute and chronic symptoms. This is a serious problem which can be overcomed by using the dust (fibre fly) collector. It can be used by all types of knitting industry and also removes maximum dust produced. This paper is about the dust collector in knitting Industry. This paper briefly discusses about the technique used in the fibre fly collector for removing the dust in knitting industry and how to avoid the risk of air pollution and effect of fibre fly.

3D orthogonal multi-resolution analysis of flow structures around an improved vehicle external mirror

2020 ◽  
pp. 095440702097536
Author(s):  
Lin Dong ◽  
Akira Rinoshika
Keyword(s):  
Reynolds Number ◽  
Large Scale ◽  
Aerodynamic Drag ◽  
Three Dimensional ◽  
Flow Structures ◽  
Small Scale ◽  
Streamwise Vortices ◽  
Number Range ◽  
Intermediate Scale ◽  
Eddy Simulation

This paper proposes vehicle door mirrors with a tip shape and ditch to reduce the aerodynamic drag. The mean drag coefficients Cd of various mirror models were first measured using load cells within a 103–105 Reynolds number range in a wind tunnel. The Cd of controlled mirrors with different ditch widths remained constant at approximately 0.75 and was lower than that of conventional mirrors. Using a large eddy simulation (LES), the 3D flow structures around modified and conventional mirrors were numerically analyzed at a Reynolds number of 2.8 × 105. Based on a three-dimensional orthogonal wavelet multi-resolution technique, the instantaneous three-dimensional vorticity and velocity were decomposed into three wavelet levels or scales: large scale with a 62 mm central scale, intermediate scale with a 29 mm central scale, and small scale with a 16 mm central scale. This indicated that the length of the region of the vorticity iso-surfaces in an improved door mirror model as the tip ditch decreases. Because the tip ditch produced the more streamwise vortices, the large-scale spanwise vortices were suppressed. The streamwise vortices and spanwise vortices of the small- and intermediate-scale structures increased, which is mainly caused by the ditch in the tip.

Small-Scale Science to Large-Scale Profession

2000 ◽  
Vol 45 (4) ◽  
pp. 396-398
Author(s):  
Roger Smith
Keyword(s):  
Large Scale ◽  
Small Scale

Development of Physics Learning Module Based on Guided Inquiry with Light Wave Material in Class XI of Senior High School

2020 ◽  
Vol 1 (1) ◽  
pp. 1-10
Author(s):  
Evi Rahmawati ◽  
Irnin Agustina Dwi Astuti ◽  
N Nurhayati
Keyword(s):  
Large Scale ◽  
Learning Strategy ◽  
Student Response ◽  
Average Score ◽  
Small Scale ◽  
Design Development ◽  
Teacher Response ◽  
Student Responses ◽  
Analysis Design ◽  
Scientific Skills

IPA Integrated is a place for students to study themselves and the surrounding environment applied in daily life. Integrated IPA Learning provides a direct experience to students through the use and development of scientific skills and attitudes. The importance of integrated IPA requires to pack learning well, integrated IPA integration with the preparation of modules combined with learning strategy can maximize the learning process in school. In SMP 209 Jakarta, the value of the integrated IPA is obtained from 34 students there are 10 students completed and 24 students are not complete because they get the value below the KKM of 68. This research is a development study with the development model of ADDIE (Analysis, Design, Development, Implementation, and Evaluation). The use of KPS-based integrated IPA modules (Science Process sSkills) on the theme of rainbow phenomenon obtained by media expert validation results with an average score of 84.38%, average material expert 82.18%, average linguist 75.37%. So the average of all aspects obtained by 80.55% is worth using and tested to students. The results of the teacher response obtained 88.69% value with excellent criteria. Student responses on a small scale acquired an average score of 85.19% with highly agreed criteria and on the large-scale student response gained a yield of 86.44% with very agreed criteria. So the module can be concluded receiving a good response by the teacher and students.

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