Non Methane Hydrocarbons variability in Athens during winter-time: The role of traffic and heating

Design Optimization of Diffuser Augmented Wind Turbine

CFD letters ◽

10.37934/cfdl.13.8.4559 ◽

2021 ◽

Vol 13 (8) ◽

pp. 45-59

Author(s):

Ahmed M. Elsayed

Keyword(s):

Wind Speed ◽

Wind Turbine ◽

Average Velocity ◽

Simplex Algorithm ◽

Optimum Form ◽

Initial Shape ◽

Low Wind Speed ◽

Numerical Parametric Study ◽

Flange Angle

The wind turbine power decreases at low wind speed. A flanged diffuser plays a role of a device for collecting and accelerating the approaching wind, and thus the optimization of the diffuser shape presents an important way to enhance the wind turbine power. In this work, a numerical parametric study was conducted on the diffuser to obtain the initial optimum form of flanged diffuser. Then, the Simplex algorithm is used to obtain the optimal diffuser shape starting from the obtained initial shape. Finally, the obtained optimum diffuser shape is used with conventional wind turbine blade. The diffuser shape is defined by four variables: open angle, flange height, centerbody length, and flange angle. The numerical simulation of flanged diffuser is carried out using the “CFDRC package. The results indicated that, the optimum diffuser shape can be obtained using simplex algorithm which maximizes the entrance average velocity to reach 1.77 times wind speed. The power augmented by a factor about 2.76:5.26 of a selected small wind turbine using the obtained diffuser shape compared to that without diffuser.

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Who Remains When Professional Farmers Give up? Some Insights on Hobby Farming in an Olive Groves-Oriented Terraced Mediterranean Area

Land ◽

10.3390/land9050168 ◽

2020 ◽

Vol 9 (5) ◽

pp. 168

Author(s):

Sabine Gennai-Schott ◽

Tiziana Sabbatini ◽

Davide Rizzo ◽

Elisa Marraccini

Keyword(s):

Agricultural Land ◽

Mediterranean Area ◽

Sociodemographic Factors ◽

Data Sources ◽

Farming Practices ◽

Structured Interviews ◽

Step Method ◽

Olive Groves ◽

First Time

Many land use systems in Mediterranean sloping areas risk abandonment because of nonprofitability, while their hydro-geological stability depends on an appropriate management. However, who are the land managers? What are their practices? Our research on the traditional olive groves of the Monte Pisano (Tuscany, Italy) reveals for the first time the quantitatively important role of hobby farmers as land managers in the area. We used a three-step-method: first, a database was constructed using several data sources to identify and map the population of olive growers; then, 35 semi-structured interviews were conducted, and finally, the data were analyzed to highlight the contribution of olive growers to the land management, along with their motivations and constraints. Our results found that hobby farmers constitute about 90% of all land managers in the study area and manage more than half of the agricultural land. They are a very uneven group, and there are no clear categories detectable by analyzing sociodemographic factors, practices and farm characteristics. They are the “same but different”, not following any market rules, as they are not profit-oriented. Their farming practices are quite homogeneous and mainly in-line with professional farming practices of that area, oriented versus a minimum input management.

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Discrete angle rotations of Bi nanoparticles embedded in a Ga matrix

Open Physics ◽

10.2478/s11534-009-0063-3 ◽

2010 ◽

Vol 8 (1) ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Avraham Be’er ◽

Richard Kofman ◽

Yossi Lereah

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Particle Size ◽

Time Resolved ◽

Transmission Electron ◽

The Difference ◽

First Time ◽

Microscopy Images ◽

Bi Nanoparticles

AbstractSpontaneous instabilities of nanoparticles are known to be influenced by the temperature, and strongly depend on the particle size. However, it is not clear what is the role of the surrounding material that is in contact with the particle. Here we report on the difference between spontaneous rotations of Bi nanoparticles embedded in amorphous SiO and those embedded in liquid Ga. The phenomenon was studied quantitatively by time resolved transmission electron microscopy using Fourier Transform analysis of highresolution electron microscopy images. While rotations of Bi nanoparticles embedded in amorphous SiO occur by all angles, the rotations of Bi nanoparticles embedded in liquid Ga occur by discrete angles. Our results point quantitatively, for the first time, to the role and importance of the contacting surrounding surface during the rotation of nanoparticles.

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Volatile and intermediate-volatility organic compounds in sub-urban Paris: variability, origin and importance for SOA formation

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-14-4841-2014 ◽

2014 ◽

Vol 14 (4) ◽

pp. 4841-4904 ◽

Cited By ~ 3

Author(s):

W. Ait-Helal ◽

A. Borbon ◽

S. Sauvage ◽

J. A. de Gouw ◽

A. Colomb ◽

...

Keyword(s):

Organic Carbon ◽

Particulate Organic Carbon ◽

Organic Compounds ◽

Integrated Approach ◽

Anthropogenic Sources ◽

Time Resolved ◽

Times Series ◽

First Time ◽

Ambient Measurements

Abstract. Measurements of gaseous and particulate organic carbon were performed during the MEGAPOLI experiments, in July 2009 and January–February 2010, at the SIRTA observatory in sub-urban Paris. Measurements of primary and secondary volatile organic compounds (VOCs), of both anthropogenic and biogenic origins, including for the first time C12-C16 n-alkanes of intermediate volatility (IVOCs), suspected to be efficient precursors of secondary organic aerosol (SOA). The time series of gaseous carbon are generally consistent with times series of particulate organic carbon at regional scales and are clearly affected by meteorology and air mass origin. Concentration levels of anthropogenic VOCs in urban and sub-urban Paris were surprisingly low (2–963 ppt) compared to other megacities worldwide and to rural continental sites. Urban enhancement ratios of anthropogenic VOC pairs agree well between the urban and sub-urban Paris sites, showing the regional extent of anthropogenic sources of similar composition. Contrary to other primary anthropogenic VOCs (aromatics and alkanes), IVOCs showed lower concentrations in winter (< 5 ppt) compared to summer (13–27 ppt) in agreement with a gas-particle partitioning in favor of their transfer to the particle phase in winter. Higher concentrations of most oxygenated VOCs in winter (18–5984 ppt) suggest their dominant primary anthropogenic origin. The respective role of primary anthropogenic gaseous compounds in regional SOA formation was investigated by estimating the SOA mass concentration expected from the anthropogenic VOCs and IVOCs (I / VOCs) measured at SIRTA. From an approach based on emissions inferred from the I / VOC concentrations times the SOA formation yields', the so-called integrated approach conducted in this study, 46% of the SOA measured at SIRTA is explained by our measured concentrations of I / VOC, with 10% explained by only C12-C16 IVOCs. From results of an alternative time-resolved approach, the explained variability of the SOA concentrations is improved when the IVOCs are taken into account. Both approaches, which are based on ambient measurements of particular I / VOCs, emphasize the importance of the intermediate volatility compounds in the SOA formation, and support previous results from chamber experiments and modeling studies. The approaches results support the need to make systematic the IVOCs speciated measurement during field campaigns.

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Protonation of Glutamate 208 Induces the Release of Agmatine in an Outward-facing Conformation of an Arginine/Agmatine Antiporter

Journal of Biological Chemistry ◽

10.1074/jbc.m110.202085 ◽

2011 ◽

Vol 286 (22) ◽

pp. 19693-19701 ◽

Cited By ~ 17

Author(s):

Elia Zomot ◽

Ivet Bahar

Keyword(s):

Binding Pocket ◽

Substrate Binding Pocket ◽

Time Resolved ◽

Extracellular Region ◽

Acidic Conditions ◽

Using Data ◽

Dynamics Simulations ◽

The Impact ◽

First Time

Virulent enteric pathogens have developed several systems that maintain intracellular pH to survive extreme acidic conditions. One such mechanism is the exchange of arginine (Arg+) from the extracellular region with its intracellular decarboxylated form, agmatine (Agm2+). The net result of this process is the export of a virtual proton from the cytoplasm per antiport cycle. Crystal structures of the arginine/agmatine antiporter from Escherichia coli, AdiC, have been recently resolved in both the apo and Arg+-bound outward-facing conformations, which permit us to assess for the first time the time-resolved mechanisms of interactions that enable the specific antiporter functionality of AdiC. Using data from ∼1 μs of molecular dynamics simulations, we show that the protonation of Glu-208 selectively causes the dissociation and release of Agm2+, but not Arg+, to the cell exterior. The impact of Glu-208 protonation is transmitted to the substrate binding pocket via the reorientation of Ile-205 carbonyl group at the irregular portion of transmembrane (TM) helix 6. This effect, which takes place only in the subunits where Agm2+ is released, invites attention to the functional role of the unwound portion of TM helices (TM6 Trp-202–Glu-208 in AdiC) in facilitating substrate translocation, reminiscent of the behavior observed in structurally similar Na+-coupled transporters.

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Non-methane hydrocarbon variability in Athens during wintertime: the role of traffic and heating

Atmospheric Chemistry and Physics ◽

10.5194/acp-18-16139-2018 ◽

2018 ◽

Vol 18 (21) ◽

pp. 16139-16154 ◽

Cited By ~ 7

Author(s):

Anastasia Panopoulou ◽

Eleni Liakakou ◽

Valérie Gros ◽

Stéphane Sauvage ◽

Nadine Locoge ◽

...

Keyword(s):

Wind Speed ◽

Atmospheric Chemistry ◽

Fossil Fuel ◽

Aerosol Formation ◽

Diurnal Variability ◽

Domestic Heating ◽

Source Profiles ◽

Morning Peak ◽

Wood Burning ◽

The Impact

Abstract. Non-methane hydrocarbons (NMHCs) play an important role in atmospheric chemistry, contributing to ozone and secondary organic aerosol formation. They can also serve as tracers for various emission sources such as traffic, solvents, heating and vegetation. The current work presents, for the first time to our knowledge, time-resolved data of NMHCs, from two to six carbon atoms, for a period of 5 months (mid-October 2015 to mid-February 2016) in the “greater Athens area” (GAA), Greece. The measured NMHC levels are among the highest reported in the literature for the Mediterranean area during winter months, and the majority of the compounds demonstrate a remarkable day-to-day variability. Their levels increase by up to factor of 4 from autumn (October–November) to winter (December–February). Microscale meteorological conditions, especially wind speed in combination with the planetary boundary layer (PBL) height, seem to contribute significantly to the variability of NMHC levels, with an increase of up to a factor of 10 under low wind speed (<3 m s−1) conditions; this reflects the impact of local sources rather than long-range transport. All NMHCs demonstrated a pronounced bimodal, diurnal pattern with a morning peak followed by a second peak before midnight. The amplitude of both peaks gradually increased towards winter, in comparison to autumn, by a factor of 3 to 6 and closely followed that of carbon monoxide (CO), which indicates a contribution from sources other than traffic, e.g., domestic heating (fuel or wood burning). By comparing the NMHC diurnal variability with that of black carbon (BC), its fractions associated with wood burning (BCwb) and fossil fuel combustion (BCff), and with source profiles we conclude that the morning peak is attributed to traffic while the night peak is mainly attributed to heating. With respect to the night peak, the selected tracers and source profiles clearly indicate a contribution from both traffic and domestic heating (fossil fuel and wood burning). NMHCs slopes versus BCwb are similar when compared with those versus BCff (slight difference for ethylene), which indicates that NMHCs are most likely equally produced by wood and oil fossil fuel burning.

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Psychological Resilience Provides No Independent Protection From Suicidal Risk

Crisis ◽

10.1027/0227-5910/a000364 ◽

2016 ◽

Vol 37 (2) ◽

pp. 130-139 ◽

Cited By ~ 9

Author(s):

Danica W. Y. Liu ◽

A. Kate Fairweather-Schmidt ◽

Richard Burns ◽

Rachel M. Roberts ◽

Kaarin J. Anstey

Keyword(s):

Risk Factors ◽

Well Being ◽

Current Status ◽

Psychological Resilience ◽

Cross Sectional ◽

Life Project ◽

Resilience Factors ◽

First Time

Abstract. Background: Little is known about the role of resilience in the likelihood of suicidal ideation (SI) over time. Aims: We examined the association between resilience and SI in a young-adult cohort over 4 years. Our objectives were to determine whether resilience was associated with SI at follow-up or, conversely, whether SI was associated with lowered resilience at follow-up. Method: Participants were selected from the Personality and Total Health (PATH) Through Life Project from Canberra and Queanbeyan, Australia, aged 28–32 years at the first time point and 32–36 at the second. Multinomial, linear, and binary regression analyses explored the association between resilience and SI over two time points. Models were adjusted for suicidality risk factors. Results: While unadjusted analyses identified associations between resilience and SI, these effects were fully explained by the inclusion of other suicidality risk factors. Conclusion: Despite strong cross-sectional associations, resilience and SI appear to be unrelated in a longitudinal context, once risk/resilience factors are controlled for. As independent indicators of psychological well-being, suicidality and resilience are essential if current status is to be captured. However, the addition of other factors (e.g., support, mastery) makes this association tenuous. Consequently, resilience per se may not be protective of SI.

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Synergetic Theory of Document in Evolution of Document Science

Herald of an Archivist ◽

10.28995/2073-0101-2018-4-1060-1068 ◽

2018 ◽

pp. 1060-1068

Author(s):

Galina A. Dvoenosova ◽

Keyword(s):

Social Role ◽

Scientific Study ◽

Self Organization ◽

Universal Theory ◽

Social Self ◽

Social Goal ◽

The Social ◽

Synergetic Theory ◽

First Time

The article assesses synergetic theory of document as a new development in document science. In information society the social role of document grows, as information involves all members of society in the process of documentation. The transformation of document under the influence of modern information technologies increases its interest to representatives of different sciences. Interdisciplinary nature of document as an object of research leads to an ambiguous interpretation of its nature and social role. The article expresses and contends the author's views on this issue. In her opinion, social role of document is incidental to its being a main social tool regulating the life of civilized society. Thus, the study aims to create a scientific theory of document, explaining its nature and social role as a tool of social (goal-oriented) action and social self-organization. Substantiation of this idea is based on application of synergetics (i.e., universal theory of self-organization) to scientific study of document. In the synergetic paradigm, social and historical development is seen as the change of phases of chaos and order, and document is considered a main tool that regulates social relations. Unlike other theories of document, synergetic theory studies document not as a carrier and means of information transfer, but as a unique social phenomenon and universal social tool. For the first time, the study of document steps out of traditional frameworks of office, archive, and library. The document is placed on the scales with society as a global social system with its functional subsystems of politics, economy, culture, and personality. For the first time, the methods of social sciences and modern sociological theories are applied to scientific study of document. This methodology provided a basis for theoretical vindication of nature and social role of document as a tool of social (goal-oriented) action and social self-organization. The study frames a synergetic theory of document with methodological foundations and basic concepts, synergetic model of document, laws of development and effectiveness of document in the social continuum. At the present stage of development of science, it can be considered the highest form of theoretical knowledge of document and its scientific explanatory theory.

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Physical Warmth Attenuates Ethnocentric Bias under Mortality Salience: An Embodied Terror Management Perspective

10.31234/osf.io/x6m8u ◽

2020 ◽

Cited By ~ 1

Author(s):

Armand Chatard ◽

Margaux Renoux ◽

Jean Monéger ◽

Leila Selimbegovic

Keyword(s):

Mortality Salience ◽

Terror Management ◽

Negative Consequences ◽

Defensive Reaction ◽

Worldview Defense ◽

Management Perspective ◽

Physical Warmth ◽

Alternative Means ◽

First Time

Research indicates that individuals often deal with mortality salience by affirming beliefs in national or cultural superiority (worldview defense). Because worldview defense may be associated with negative consequences (discrimination), it is important to identify alternative means to deal with death-related thoughts. In line with an embodied terror management perspective, we evaluate for the first time the role of physical warmth in reducing defensive reaction to mortality salience. We predicted that, like social affiliation (social warmth), physical warmth could reduce worldview defense when mortality is salient. In this exploratory (preregistered) study, 202 French participants were primed with death-related thoughts, or an aversive control topic, in a heated room or a non-heated room. The main outcome was worldview defense (ethnocentric bias). We found no main effect of mortality salience on worldview defense. However, physical warmth reduced worldview defense when mortality was salient. Implications for an embodied terror management perspective are discussed.

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Relationship between big five personality model and abusive supervision

10.34091/ajss.12.2.05 ◽

2019 ◽

Vol 12 (2) ◽

Cited By ~ 1

Author(s):

Bibi Tahira ◽

Naveed Saif ◽

Muhammad Haroon ◽

Sadaqat Ali

Keyword(s):

Big Five ◽

Abusive Supervision ◽

State Universities ◽

Big Five Personality ◽

Big Five Model ◽

The Impact ◽

First Time ◽

Supervisor Behavior ◽

Moderating Role

The current study tries to understand the diverse nature of relationship between personality Big Five Model (PBFM) and student's perception of abusive supervision in higher education institutions of Khyber Pakhtoonkhwa Pakistan. Data was collected in dyads i.e. (supervisors were asked to rate their personality attributes while student were asked to rate the supervisor behavior) through adopted construct. For this purpose, data was collected from three government state universities and one Private Sector University. The focus was on MS/M.Phill and PhD student and their supervisors of the mentioned universities. After measuring normality and validity regression analysis was conducted to assess the impact of supervisor personality characteristics that leads to abusive supervision. Findings indicate interestingly that except agreeableness other four attributes of (PBFM) are play their role for abusive supervision. The results are novel in the nature as for the first time Neuroticism, openness to experience, extraversion and conscientiousness are held responsible for the abusive supervision. The study did not explore the demographic characteristics, and moderating role of organizational culture, justice and interpersonal deviances to understand the strength of relationship in more detail way. Keywords: Personality big five model, abusive supervision, HEIs

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