The Environmental Pollution Analysis of Aircraft

2012 ◽  
Vol 518-523 ◽  
pp. 2259-2262
Author(s):  
Xiao Jie Chen

The Environmental factors cover a wide range of aspects but noise and emissions are the main regulatory issues which affect the design of the aircraft. Both are largely associated with engine design aspects and aircraft flight profiles. With the expected growth in air traffic at the major airports the environmental pressure groups will become more vocal. This paper shows the influence of airworthiness and environmental influences of aircraft. Both noise and emission pollution were discussed. Several methods were given to reduce these environment pollution on the base of the analysis.

Reproduction ◽  
2001 ◽  
pp. 205-214 ◽  
Author(s):  
SM Rhind ◽  
MT Rae ◽  
AN Brooks

Research from a wide range of scientific disciplines has shown that the reproductive performance of animals in adult life is determined, in part, by a variety of extraneous influences acting at different stages of development from before conception until after birth. These effects are probably mediated through changes in the hypothalamic-pituitary and gonadal axes but the physiological system that is affected depends on the stage of development at which the influence is applied. The physiological mechanisms through which environmental influences are transmitted to the target organs are, in many cases, complex and poorly understood. Gonadotrophins seem to play a pivotal role in the development of the fetal testis, although effects of environmental influences on GnRH secretion have yet to be demonstrated. Other studies have shown that, at earlier stages of fetal development, the normal ontogeny of gonadal development and function can be disrupted by undernutrition or the influence of endocrine-disrupting compounds. Specifically, in female fetuses, the onset of meiosis is delayed, whereas, in male fetuses, testosterone synthesis is increased as a result of enhanced testicular steroidogenic enzyme activity. Although reproductive performance is clearly influenced by prenatal factors, much further work is required to identify the relationships between developmental abnormalities and adult reproductive function. Work is also required to elucidate further the critical windows in development and the mechanisms by which environmental factors affect the reproductive organs of developing offspring.


2006 ◽  
Vol 14 (2) ◽  
pp. 89-136 ◽  
Author(s):  
Paresh Lacoul ◽  
Bill Freedman

Aquatic plants are important components of many freshwater ecosystems. In this review we examine natural and anthropogenic influences on the distribution and abundance of aquatic plants, and develop a conceptual model of those diverse interactions. Species of aquatic plants vary greatly in their anatomy, physiology, life-history traits, and ability to tolerate inorganic and biological stressors. Key examples of inorganic stressors are extreme regimes of flow velocity, irradiance, salinity, ice cover, temperature, nutrients, and pollutants. Stressors associated with competition, herbivory, and disease may also limit the ability of species to utilize otherwise suitable habitats. Some aquatic plants have a cosmopolitan distribution and display high levels of polymorphism and phenotypic plasticity in response to variations of environmental factors; these qualities allow them to occur over a wide range of conditions. Other species, however, have narrower tolerances and are potentially useful indicators of environmental conditions, in terms of either their presence or relative abundance within communities. In this review, we examine key environmental influences affecting aquatic plants, and their potential use as indicators at local, watershed, and regional scales.Key words: aquatic plants (aquatic macrophytes), environmental factors, environmental indicators, environmental stressors.


2018 ◽  
Vol 6 (2) ◽  
Author(s):  
Arie Herlambang

Basically, nature has the ability to perform the restoration of environmental damage caused by increased human activity, but because of the limited carrying capacity, then the environment has decreased the quality from year to year. In saving the environment, technology plays a role in reducing the risk of pollution, increased efi siensi process, and creating processes and environmentall friendly products, monitoring and prediction of environment quality, environmental pollution control, restoration and environmental improvement. Waste Technology (end of pipe technology) are widely used to cope with environmental pollution, both for liquid waste, solid and air. Waste processing technology developed for the waste can be in accordance with quality standards thathave been established, while monitoring technology has been developed either manually or automatically. For recovery and improvement of technology has been developed remedies and restoration that rely on bacteria in nature.Keywords: end of pipe technology, reuse, recycle, reduce (3R), carrying capacity, and environment pollution


Author(s):  
Alyssa T Brooks ◽  
Hannah K Allen ◽  
Louise Thornton ◽  
Tracy Trevorrow

Abstract Health behavior researchers should refocus and retool as it becomes increasingly clear that the challenges of the COVID-19 pandemic surpass the direct effects of COVID-19 and include unique, drastic, and ubiquitous consequences for health behavior. The circumstances of the pandemic have created a natural experiment, allowing researchers focusing on a wide range of health behaviors and populations with the opportunity to use previously collected and future data to study: (a) changes in health behavior prepandemic and postpandemic, (b) health behavior prevalence and needs amidst the pandemic, and (c) the effects of the pandemic on short- and long-term health behavior. Our field is particularly challenged as we attempt to consider biopsychosocial, political, and environmental factors that affect health and health behavior. These realities, while daunting, should call us to action to refocus and retool our research, prevention, and intervention efforts


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yisong Huang ◽  
Shaoyong Su ◽  
Harold Snieder ◽  
Frank Treiber ◽  
Gaston Kapuku ◽  
...  

AbstractIncreased arterial stiffness measured by pulse wave velocity (PWV) is an important parameter in the assessment of cardiovascular risk. Our previous longitudinal study has demonstrated that carotid-distal PWV showed reasonable stability throughout youth and young adulthood. This stability might be driven by genetic factors that are expressed consistently over time. We aimed to illustrate the relative contributions of genetic and environmental factors to the stability of carotid-distal PWV from youth to young adulthood. We also examined potential ethnic differences. For this purpose, carotid-distal PWV was measured twice in 497 European American (EA) and African American (AA) twins, with an average interval time of 3 years. Twin modelling on PWV showed that heritability decreased over time (62–35%), with the nonshared environmental influences becoming larger. There was no correlation between the nonshared environmental factors on PWV measured at visit 1 and visit 2, with the phenotypic tracking correlation (r = 0.32) completely explained by shared genetic factors over time. Novel genetic influences were identified accounting for a significant part of the variance (19%) at the second measurement occasion. There was no evidence for ethnic differences. In summary, novel genetic effects appear during development into young adulthood and account for a considerable part of the variation in PWV. Environmental influences become larger with age for PWV.


1973 ◽  
Vol 7 (1) ◽  
pp. 1-15
Author(s):  
H. G. Nicholas

Elections satisfy both the practical and the theoretical requirements of classical democratic theory if they answer one question only: Who shall rule? Judged by this test the American elections of 7 November 1972 returned as clear and unequivocal an answer as the United States Constitution permits – crystal-clear as to individuals, equivocal as to parties and political forces. But the student of politics and society cannot resist treating elections as data-gathering devices on a wide range of other questions, on the state of the public mind, on the relative potency of pressure groups, on the internal health of the political parties, and, of course, on the shape of things to come. In this ancillary role American elections, despite the generous wealth of statistical material which they throw up – so much more detailed and categorized (though often less precise) than our own – Suffer in most years from one severe limitation, a limitation which in 1972 was particularly conspicuous; they do not engage the interest of more than a moderate percentage of the American citizenry. In 1972 that percentage was as low as 55 per cent, i.e. out of an estimated eligible population of 139,642,000 only 77,000,000 went to the polls. Since this circumscribes the conclusions which can be drawn from the results themselves, as well as constituting a phenomenon of considerable intrinsic interest, it seems worthwhile to begin any examination of the 1972 elections by an analysis not of the votes counted but of those which were never cast.


2020 ◽  
Author(s):  
Joshua M. Tybur ◽  
Laura Wesseldijk ◽  
Patrick Jern

Dozens of studies indicate that individuals more prone to experiencing disgust have stronger symptoms of anxiety disorders – especially contamination sensitivity. However, no work has informed the degree to which this relationship arises from genetic versus environmental factors. The present study fills this gap by measuring disgust proneness and contamination sensitivity in a sample of 7,199 twins and siblings of twins, including 1,411 complete twin pairs. Disgust proneness was related to contamination sensitivity, r = .32. Multivariate twin modeling revealed that genetic factors accounted for 34% and 40% of the variance in disgust proneness and contamination sensitivity, respectively, and that the correlation between the two traits reflected overlapping genetic (54%) and unshared environmental (46%) – but not shared environmental – influences. While consistent with work indicating that disgust proneness relates to contamination sensitivity, results suggest that parental-modeling hypotheses for explaining this relationship be re-evaluated.


2021 ◽  
Vol 8 ◽  
Author(s):  
Tie-Ning Zhang ◽  
Qi-Jun Wu ◽  
Ya-Shu Liu ◽  
Jia-Le Lv ◽  
Hui Sun ◽  
...  

Background: The etiology of congenital heart disease (CHD) has been extensively studied in the past decades. Therefore, it is critical to clarify clear hierarchies of evidence between types of environmental factors and CHD.Methods: Electronic searches in PubMed, Embase, Web of Science, Cochrane database were conducted from inception to April 20, 2020 for meta-analyses investigating the aforementioned topic.Results: Overall, 41 studies including a total of 165 meta-analyses of different environmental factors and CHD were examined, covering a wide range of risk factors. The summary random effects estimates were significant at P < 0.05 in 63 meta-analyses (38%), and 15 associations (9%) were significant at P < 10−6. Of these meta-analyses, eventually one risk factor (severe obesity; relative risk: 1.38, 95% confidence interval: 1.30–1.47) had significant summary associations at P < 10−6, included more than 1,000 cases, had 95% prediction intervals excluding the null value, and were not suggestive of large heterogeneity (I2 < 50%), small-study effects (P-value for Egger's test > 0.10), or excess significance (P > 0.10). Eight associations (5%) (including maternal lithium exposure, maternal obesity, maternal alcohol consumption, and maternal fever) had results that were significant at P < 10−6, included more than 1,000 cases, and had 95% prediction intervals excluding the null value (highly suggestive).Conclusion: This umbrella review shows that many environmental factors have substantial evidence in relation to the risk of developing CHD. More and better-designed studies are needed to establish robust evidence between environmental factors and CHD.Systematic Review Registration: [PROSPERO], identifier [CRD42020193381].


Author(s):  
Pascal Prado ◽  
Yulia Panchenko ◽  
Jean-Yves Tre´panier ◽  
Christophe Tribes

Preliminary Multidisciplinary Design Optimization (PMDO) project addresses the development and implementation of the Multidisciplinary Design Optimization (MDO) methodology in the Concept/Preliminary stages of the gas turbine design process. These initial phases encompass a wide range of coupled engineering disciplines. The PMDO System is a software tool intended to integrate existing design and analysis tools, decompose coupled multidisciplinary problems and, therefore, allow optimizers to speed-up preliminary engine design process. The current paper is a brief presentation of the specifications for the PMDO System as well as a description of the prototype being developed and evaluated. The current assumed e xible architecture is based on three software components that can be installed on different computers: a Java/XML MultiServer, a Java Graphical User Interface and a commercial optimization software.


Author(s):  
Nicolae Bodrug ◽  

. Environmental pollution affects population health depending on the extension and the degree of exposure to environmental factors. In most cases it is difficult to obtain an accurate situation of exposure of population to harmful factors. Health status is determined by: human biology, ecological factors, the socio-economic situation of each person, and the quality of medical services. In according to regional peculiarities the interdependence of those factors could vary, but not significantly. The environmental risks are everywhere but diminishing them may improve the health status of the population.


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