When Liquid Rays Become Gas Rays: Can Evaporation Ever Be Non-Maxwellian?

Molecular Beams in Physics and Chemistry ◽

10.1007/978-3-030-63963-1_27 ◽

2021 ◽

pp. 631-647

Author(s):

Gilbert M. Nathanson

Keyword(s):

Average Energy ◽

Phase Speed ◽

Weighted Average ◽

High Energy ◽

Potential Of Mean Force ◽

Ray Method ◽

Speed Distribution ◽

Evaporation Flux ◽

He Atom

AbstractA rare mistake by Otto Stern led to a confusion between density and flux in his first measurement of a Maxwellian speed distribution. This error reveals the key role of speed itself in Stern’s development of “the method of molecular rays”. What if the gas-phase speed distributions are not Maxwellian to begin with? The molecular beam technique so beautifully advanced by Stern can also be used to explore the speed distribution of gases evaporating from liquid microjets, a tool developed by Manfred Faubel. We employ liquid water and alkane microjets containing dissolved helium atoms to monitor the speed of evaporating He atoms into vacuum. While most dissolved gases evaporate in Maxwellian speed distributions, the He evaporation flux is super-Maxwellian, with energies up to 70% higher than the flux-weighted average energy of 2 RTliq. The explanation of this high-energy evaporation involves two beautiful concepts in physical chemistry: detailed balancing between He atom evaporation and condensation (starting with gas-surface collisions) and the potential of mean force on the He atom (starting with He atoms just below the surface). We hope that these measurements continue to fulfill Stern’s dream of the “directness and simplicity of the molecular ray method.”

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Catch them Young : Role of Educational Institutions in Community Development- A Descriptive Study on the Perception of College Students in Chennai

GIS Business ◽

10.26643/gis.v14i6.11694 ◽

2019 ◽

Vol 14 (6) ◽

pp. 170-182

Author(s):

Dr. R. Sundari ◽

Ms. Sangeetha Manoj

Keyword(s):

Community Development ◽

Collective Action ◽

Body Politic ◽

Weighted Average ◽

Well Being ◽

Educational Institutions ◽

Average Score ◽

Academic Institutions ◽

Grass Root Level

Community Development is a process of collective action taken by the members of a community to generate solutions for common problems. The aspects of community well being namely Economic, Social, Environmental and Cultural well being evolves from this type of collective action taken at multiple societal levels. (Weaver, 1971) defines community development as a process of “A public-group approach dedicated to achieving the goals of the total body politic.” Therefore, it is evident that a community can be developed through the effective participation of citizens. It is universally acceptable that community service is a vehicle for safeguarding the environment that is initiated from the participants of the community. In order to imbibe the community consciousness among the citizens, every country should “Catch them Young”. The purpose of the paper is to integrate Participative Model (Active Citizenship, Citizen Networks and Co-production) with Self-service Model (Social Governance, Societal Discipline and Accountability). National and international reviews show that the perception about the community and realisation has to be ingrained at the grass root level; this can be achieved through the participation of academic institutions. This paper is an attempt to highlight. The initiatives taken by educational institutions to imbibe social consciousness, The perceptions of students about their role in community development, and, To identify the effective Private Public Partnership areas for community building Factor analysis has been applied to identify the role of educational institutions and individual citizen’s( Students) in building community consciousness. Linear Regression had been applied in the study to measure the influence of Educational Institutions on the role of Students in building the community. A weighted average score is awarded by the students for the potential areas of public private partnership for community development is highlighted. The results of the study provide an impact created by the institution over the students. The Study also, consolidates some of the successful community bonding and building activities carried out Academic Institutions.

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Fundamentality

10.1093/oso/9780198714057.003.0013 ◽

2017 ◽

Author(s):

Richard Healey

Keyword(s):

Quantum Theory ◽

High Energy Physics ◽

Physical Property ◽

Natural World ◽

High Energy ◽

Quantum Field Theories ◽

Fundamental Physics ◽

The World ◽

Energy Physics

The metaphor that fundamental physics is concerned to say what the natural world is like at the deepest level may be cashed out in terms of entities, properties, or laws. The role of quantum field theories in the Standard Model of high-energy physics suggests that fundamental entities, properties, and laws are to be sought in these theories. But the contextual ontology proposed in Chapter 12 would support no unified compositional structure for the world; a quantum state assignment specifies no physical property distribution sufficient even to determine all physical facts; and quantum theory posits no fundamental laws of time evolution, whether deterministic or stochastic. Quantum theory has made a revolutionary contribution to fundamental physics because its principles have permitted tremendous unification of science through the successful application of models constructed in conformity to them: but these models do not say what the world is like at the deepest level.

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Pannexins and Connexins: Their Relevance for Oocyte Developmental Competence

International Journal of Molecular Sciences ◽

10.3390/ijms22115918 ◽

2021 ◽

Vol 22 (11) ◽

pp. 5918

Author(s):

Paweł Kordowitzki ◽

Gabriela Sokołowska ◽

Marta Wasielak-Politowska ◽

Agnieszka Skowronska ◽

Mariusz T. Skowronski

Keyword(s):

Assisted Reproductive Technologies ◽

Mammalian Species ◽

Atp Release ◽

Reproductive Technologies ◽

High Energy ◽

Developmental Competence ◽

Physiological Processes ◽

Protein Group ◽

Multicellular Organisms

The oocyte is the major determinant of embryo developmental competence in all mammalian species. Although fundamental advances have been generated in the field of reproductive medicine and assisted reproductive technologies in the past three decades, researchers and clinicians are still trying to elucidate molecular factors and pathways, which could be pivotal for the oocyte’s developmental competence. The cell-to-cell and cell-to-matrix communications are crucial not only for oocytes but also for multicellular organisms in general. This latter mentioned communication is among others possibly due to the Connexin and Pannexin families of large-pore forming channels. Pannexins belong to a protein group of ATP-release channels, therefore of high importance for the oocyte due to its requirements of high energy supply. An increasing body of studies on Pannexins provided evidence that these channels not only play a role during physiological processes of an oocyte but also during pathological circumstances which could lead to the development of diseases or infertility. Connexins are proteins that form membrane channels and gap-junctions, and more precisely, these proteins enable the exchange of some ions and molecules, and therefore they do play a fundamental role in the communication between the oocyte and accompanying cells. Herein, the role of Pannexins and Connexins for the processes of oogenesis, folliculogenesis, oocyte maturation and fertilization will be discussed and, at the end of this review, Pannexin and Connexin related pathologies and their impact on the developmental competence of oocytes will be provided.

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Evaluation of the Effectiveness of Brazilian Community Restaurants for the Dimension of Low-Income People Access to Food

Nutrients ◽

10.3390/nu13082671 ◽

2021 ◽

Vol 13 (8) ◽

pp. 2671

Author(s):

Mateus Santana Sousa ◽

Camila Silveira Silva Teixeira ◽

Jamacy Costa Souza ◽

Priscila Ribas de Farias Costa ◽

Renata Puppin Zandonadi ◽

...

Keyword(s):

Low Income ◽

Formal Education ◽

Average Energy ◽

Secondary Data ◽

Target Population ◽

Service Capacity ◽

The Public ◽

The Government ◽

Access To Food

This study aimed to evaluate the effectiveness of community restaurants (CRs), managed by the Government of the State of Bahia/Brazil, for the dimension of access to food. The study used secondary data obtained from the public opinion survey Profile of users of community restaurants in Salvador. The nutritional information was accessed through the analysis of CRs’ menus. Adequate effectiveness of access to food was considered when the CR served meals to 50% to 70% of the users considered the target audience (individuals served by the two CRs located in the city of Salvador/Bahia/Brazil). The participants (n = 1464; 778 as low-income individuals) were adult CR users from Salvador/Brazil. Most of the respondents were male, 40 to 54 years old, not white, had up to 9 years of formal education, without a partner, and living in the municipality of Salvador. The evaluated CRs are effective in serving 53.1% of the target population in their total service capacity. Meal provision only reached an estimated 0.7% of the socially vulnerable community in the district. The average energy value of the meal served by the CR units was 853.05 kcal/meal, with a mean energy density composition classified as average (1.15 kcal/g). The effectiveness of the evaluated community restaurants showed that these instruments were minimally effective in promoting access to food for the low-income population within their total daily service capacity, and the current quantity of these facilities was insufficient. However, these instruments stand out in the fundamental role of promoting the daily distribution of meals to the Brazilian population with the highest social vulnerability levels.

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POS1388 ULTRASOUND FOR PANNICULITIS

Annals of the Rheumatic Diseases ◽

10.1136/annrheumdis-2021-eular.663 ◽

2021 ◽

Vol 80 (Suppl 1) ◽

pp. 977.1-977

Author(s):

A. Potapova ◽

O. Egorova ◽

O. Alekseeva ◽

A. Volkov ◽

S. Radenska-Lopovok

Keyword(s):

Dynamic Range ◽

Subcutaneous Fat ◽

Diagnostic Value ◽

High Energy ◽

Contralateral Side ◽

Imaging Method ◽

Non Invasive ◽

M 12

Background:Ultrasound (US) is a non-invasive and safe imaging method that allows in vivo differentiation of the morphological structures of subcutaneous fat (SCF) tissue in in normal and pathology.Objectives:Reveal features of ultrasound changes in SCF in panniculitis (Pn).Methods:57 patients (f – 45, m - 12) aged 18 - 67 years with an initial diagnosis of erythema nodosum and a disease duration of 3.6 ± 1.4 years were examined. In addition to the general clinical examination, a computed tomography of the chest organs and a pathomorphological examination of a skin biopsy from the site of the node were performed. Ultrasound was performed on a MyLabTwice apparatus (ESAOTE, Italy) using a multi-frequency linear transducer (10-18 MHz) with the PD technique, the parameters of which were adapted for recording low-speed flows (PRF 300-600 Hz, low filter, dynamic range - 20-40 dB), the presence of vascularization was assessed not only in the affected area, but also on the contralateral side using high-energy Doppler.Results:33 patients were diagnosed with septal Pn (SPn), 24 - lobular Pn (LPn). In all cases, the diagnosis was verified by histological examination. Ultrasound made it possible to assess the thickness, echoicity and vascularization of the SCF. In 35 patients, significant thickening of the SCF was revealed (as compared to the contralateral side), of which in 14 cases with SPn, in 21 - with LPn. Significant diffuse thickening of the SCF with the contralateral side was observed in 18 patients, incl. in 12 (66%) patients with LPn. Limited thickening was more typical for SPn (73%). A significant increase in the echoicity of the SCF was noted in all forms of Pn. A “lobular” echo pattern with an anechogenic environment was observed in 25 patients, of which 18 (72%) had LPn. An increase in vascularization compared to the contralateral side was recorded in 30 cases (SPn-17, LPn-13).Conclusion:The obtained preliminary results indicate the important role of ultrasound in assessing the depth and prevalence of the inflammatory process at Pn. To clarify the diagnostic value of this method, further studies are needed on a larger sample of patients.Disclosure of Interests:None declared

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Applications of Energy Beams in Material and Device Processing

MRS Proceedings ◽

10.1557/proc-23-25 ◽

1983 ◽

Vol 23 ◽

Author(s):

G.J. Galvin ◽

L.S. Hung ◽

J.W. Mayer ◽

M. Nastasi

Keyword(s):

Ion Beam ◽

High Energy ◽

Ion Beams ◽

Traditional Role ◽

Near Surface ◽

Device Processing ◽

Composition Modification ◽

Directed Energy ◽

Transistor Fabrication

ABSTRACTEnergetic ion beams used outside the traditional role of ion implantation are considered for semiconductor applications involving interface modification for self-aligned silicide contacts, composition modification for formation of buried oxide layers in Si on insulator structures and reduced disorder in high energy ion beam annealing for buried collectors in transistor fabrication. In metals, aside from their use in modification of the composition of near surface regions, energetic ion beams are being investigated for structural modification in crystalline to amorphous transitions. Pulsed beams of photons and electrons are used as directed energy sources in rapid solidification. Here, we consider the role of temperature gradients and impurities in epitaxial growth of silicon.

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The role of high-energy protons and electrons in powering the solar white-light flare emission

Solar Physics ◽

10.1007/bf00146341 ◽

1996 ◽

Vol 167 (1-2) ◽

pp. 307-320 ◽

Cited By ~ 1

Author(s):

E. Rieger ◽

D. F. Neidig ◽

D. W. Engfer ◽

D. Strelow

Keyword(s):

White Light ◽

High Energy

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The Role of Equatorial Rossby Waves in Tropical Cyclogenesis. Part I: Idealized Numerical Simulations in an Initially Quiescent Background Environment

Monthly Weather Review ◽

10.1175/2009mwr3114.1 ◽

2010 ◽

Vol 138 (4) ◽

pp. 1368-1382 ◽

Cited By ~ 15

Author(s):

Jeffrey S. Gall ◽

William M. Frank ◽

Matthew C. Wheeler

Keyword(s):

Tropical Cyclone ◽

Large Scale ◽

Phase Speed ◽

Tropical Cyclogenesis ◽

Initial Amplitude ◽

Low Level ◽

Wave Simulation ◽

Horizontal Momentum ◽

Good Agreement

Abstract This two-part series of papers examines the role of equatorial Rossby (ER) waves in tropical cyclone (TC) genesis. To do this, a unique initialization procedure is utilized to insert n = 1 ER waves into a numerical model that is able to faithfully produce TCs. In this first paper, experiments are carried out under the idealized condition of an initially quiescent background environment. Experiments are performed with varying initial wave amplitudes and with and without diabatic effects. This is done to both investigate how the properties of the simulated ER waves compare to the properties of observed ER waves and explore the role of the initial perturbation strength of the ER wave on genesis. In the dry, frictionless ER wave simulation the phase speed is slightly slower than the phase speed predicted from linear theory. Large-scale ascent develops in the region of low-level poleward flow, which is in good agreement with the theoretical structure of an n = 1 ER wave. The structures and phase speeds of the simulated full-physics ER waves are in good agreement with recent observational studies of ER waves that utilize wavenumber–frequency filtering techniques. Convection occurs primarily in the eastern half of the cyclonic gyre, as do the most favorable conditions for TC genesis. This region features sufficient midlevel moisture, anomalously strong low-level cyclonic vorticity, enhanced convection, and minimal vertical shear. Tropical cyclogenesis occurs only in the largest initial-amplitude ER wave simulation. The formation of the initial tropical disturbance that ultimately develops into a tropical cyclone is shown to be sensitive to the nonlinear horizontal momentum advection terms. When the largest initial-amplitude simulation is rerun with the nonlinear horizontal momentum advection terms turned off, tropical cyclogenesis does not occur, but the convectively coupled ER wave retains the properties of the ER wave observed in the smaller initial-amplitude simulations. It is shown that this isolated wave-only genesis process only occurs for strong ER waves in which the nonlinear advection is large. Part II will look at the more realistic case of ER wave–related genesis in which a sufficiently intense ER wave interacts with favorable large-scale flow features.

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