cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Electro-fluorescence characterization of oxidative and reductive desorpton{sic} of thiol monolayers
Creators: name: Musgrove, Amanda
Publisher: name: University of British Columbia
Year: 2010

description: The electro-fluorescence microscopy technique was used to characterize the oxidative and reductive desorption behavior of fluorescent-tagged thiol self-assembled monolayers on a polycrystalline gold electrode. Effects of pH and thiol alkyl chain length on desorption potential and fluorescence behavior were studied. The use of an alternating 'base-step' potential was established in order to eliminate uncertainty in capacitance measurements arising from chargetransfer reactions (H2 evolution or gold oxidation) occurring at more extreme potential values. The potential of monolayer desorption, here defined as the potential at which the capacitance of the electrode interface begins to change rapidly with potential, was found to be affected by solution pH. Electrolyte solutions with a higher pH required a lower potential to desorb the thiol monolayers. An increase in fluorescence intensity at the electrode surface accompanied the change in capacitance, confirming that the thiol molecules are migrating away from the electrode. Evidence of oxidative readsorption following reduction of the monolayer was also observed, both by the associated decrease in capacitance and a dramatic decrease in fluorescence intensity. Fluorescence intensity during oxidative desorption was found to be linked to the pH of the environment surrounding the electrode surface. Lower fluorescence intensity was associated with a decrease in solution pH, and was also observed at the step (oxidizing) potential. The decrease in fluorescence at the step potential is believed to be linked to a local decrease in electrolyte pH at the electrode surface due to the oxidation of gold. The oxidation products are expected to be less soluble in acidic media, causing aggregation and self-quenching of the BODIPY fluorophore used. On return to the base potential, the local pH was returned to the bulk solution pH, and fluorescence was restored. At all pH values studied, a more extreme potential was required to desorb the thiol with the longer alkyl chain (16 carbon atoms) than the shorter-chain thiol studied (10 carbon atoms).
The role of science in sustainable development of agriculture according to the Polish scientific community
Creators: name: Sadowski, Arkadiusz
name: Baer-Nawrocka, Agnieszka
name: Czubak, Wawrzyniec
name: Sadowski, Arkadiusz
name: Baer-Nawrocka, Agnieszka
name: Czubak, Wawrzyniec
Publisher: name: Unknown
Year: 2013
Subjects: subject: Community/Rural/Urban Development
subject: International Development
subject: Research and Development/Tech Change/Emerging Technologies
subject: Rural development programme
subject: Slovenia
subject: sustainable agriculture

description: Sustainable development of agriculture and rural areas is a complex issue. Therefore, identifying the needs for sustainability, study the stage of its conceptualization, developing methods and implementation instruments, require the involvement of different scientific fields. Their role varies both in concept and implementation. The aim of the research was to determine the scientific community representatives’ opinion on the role of science and its particular fields in the implementation of sustainable development of agriculture and rural areas. This analysis was preceded by determining the importance of science against the background of other factors. Surveys were conducted using a structured interview with 128 representatives of socio-economic and the life sciences. Basic descriptive statistics were used to characterize the obtained results. The vast majority of respondents stated that implementing the ideas of sustainable development of agriculture and rural areas is possible and justified. Analyses have shown that at the current stage of sustainable development implementation, the most important factors include scientific research and transfer of new technologies (in addition to political decisions). Such an opinion is expressed by the experts regardless of scientific field they represent (socio-economic and the life sciences). Moreover, ecology has been indicated as a science that mostly contributes to implementing principles for sustainable development of agriculture. Less importance has been, in turn, attached to the political sciences. The role of life and agricultural sciences (agronomy, zootechnics, veterinary medicine, agricultural chemistry) was rated more highly by representatives of the life sciences. The idea of sustainable development is still evolving concept, which is indirectly indicated by the opinions about increasing need for further engaging all scientific fields that were analyzed. Experts claim that in the future the role of sociology and rural sociology in implementing concepts will increase most significantly, which may indicate that a better understanding of social order will be required.
$Sr\_{14}Cu\_{24}O\_{41}$ : a complete model for the chain sub-system
Creators: name: Gellé, Alain
name: Lepetit, Marie-Bernadette
Publisher: name: arXiv
Year: 2004
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: A second neighbor $t-J+V$ model for the chain subsystem of the $Sr\_{14}Cu\_{24}O\_{41}$ has been extracted from ab-initio calculations. This model does not use periodic approximation but describes the entire chain through the use of the four-dimensional crystallographic description. Second neighbors interactions are found to be of same order than the first neighbors ones. The computed values of the second neighbors magnetic interaction are coherent with experimental estimations of the intra-dimer magnetic interactions, even if slightly smaller. The reasons of this underestimation are detailed. The computed model allowed us to understand the origin of the chain dimerisation and predicts correctly the relative occurrence of dimers and free spins. The orbitals respectively supporting the magnetic electrons and the holes have been found to be essentially supported by the copper 3d orbitals (spins) and the surrounding oxygen $2p$ orbitals (holes), thus giving a strong footing to the existence of Zhang-Rice singlets.
Requirements of organic farming and impact on direct costs of organic production
Creators: name: Zekalo, Marcin
name: Zekalo, Marcin
Publisher: name: Unknown
Year: 2013
Subjects: subject: Community/Rural/Urban Development
subject: Environmental Economics and Policy
subject: Farm Management
subject: requirements of organic farming
subject: direct costs of production

description: Information and knowledge are now considered the most important factors for the development of the farm, and in the economic aspect they often allow to build competitive advantages. Naturally, the requirements of today's food production sector go beyond the economic effects of the production and also apply to meeting the environmental requirements. Organic farming as a holistic system can be such a proposal for management, but it places high demands on farmers. Restricted legislation in organic farming regulates in detail the manner of production, impacting directly on production character and also economic results achieved in organic farms. Farmers using theoretical and practical knowledge are needed to meet all formal requirements and they want to achieve the best economic results of production. We can point out the strengths of organic production, which by using natural resources, best agricultural techniques and sustainable plant and animal production can lead to a reduction of direct costs of production. The results of studies on the AGROKOSZTY system, relating to the economics of organic production, indicate lower than in conventional farms direct costs of production, as well as good income performance from particular production activities.
Scaling violations of quark and gluon jet fragmentation functions in e+e- annihilations
Creators: name: Tasevsky, Marek
Publisher: name: arXiv
Year: 2004
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Flavour inclusive, udsc and b fragmentation functions in biased and unbiased jets and gluon fragmentation functions in biased jets are measured in e+e- annihilations using OPAL data collected at energies Ecms = 91.2 and 183-209 GeV.
description: 5 pages, 4 figures. To appear in Proceedings of Workshop on Deep Inelastic Scattering 2004 (DIS04), Strbske Pleso, Slovakia, 14-18.04.2004
The cyclotron line energy in Her X-1: stable after the decay
Creators: name: Staubert, R.
name: Ducci, L.
name: Ji, L.
name: Fuerst, F.
name: Wilms, J.
name: Rothschild, R. E.
name: Pottschmidt, K.
name: Brumback, M.
name: Harrison, F.
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We summarize the results of a dedicated effort between 2012 and 2019 to follow the evolution of the cyclotron line in Her~X-1 through repeated NuSTAR observations. The previously observed nearly 20-year long decay of the cyclotron line energy has ended around 2012: from there onward the pulse phase averaged flux corrected cyclotron line energy has remained stable and constant at an average value of Ecyc= (37.44+/-0.07) keV (normalized to a flux level of 6.8 RXTE/ASM-cts/s). The flux dependence of Ecyc discovered in 2007 is now measured with high precision, giving a slope of (0.675+/-0.075) keV/(ASM-cts/s), corresponding to an increase of 6.5% of Ecyc for an increase in flux by a factor of two. We also find that all line parameters as well as the continuum parameters show a correlation with X-ray flux. While a correlation between Ecyc and X-ray flux (both positive and negative) is now known for several accreting binaries with various suggestions for the underlying physics, the phenomenon of a long-term decay has so far only been seen in Her~X-1 and Vela~X-1, with far less convincing explanations.
description: 13 pages, 17 figures, Astronomy and Astrophysics (in press)
A Lobster-inspired Hybrid Actuator With Rigid and Soft Components
Creators: name: Chen, Yaohui
name: Le, Sing
name: Tan, Qiao Chu
name: Lau, Oscar
name: Song, Chaoyang
Publisher: name: arXiv
Year: 2020
Subjects: subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: Soft actuators have drawn significant attention from researchers with an inherently compliant design to address the safety issues in physical human-robot interactions. However, they are also vulnerable and pose new challenges in the design, fabrication, and analysis due to their inherent material softness. In this paper, a novel hybrid actuator design is presented with bio-inspirations from the lobster, or crustaceans in a broader perspective. We enclose a soft chamber with rectangular cross-section using a series of articulated rigid shells to produce bending under pneumatic input. By mimicking the shell pattern of lobsters' abdomen, foldable rigid shells are designed to provide the soft actuator with full protection throughout the motion range. The articulation of the rigid shells predefines the actuator's bending motions. As a result, the proposed design enables one to analyze this hybrid actuator with simplified quasi-static models and rigid-body kinematics, which are further validated by mechanical tests. This paper demonstrates that the proposed hybrid actuator design is capable of bridging the major design drawbacks of the entirely rigid and soft robots while preserving their engineering merits in performance.
description: 9 pages, 7 figures, accepted for ASME DETC 2017
ATTITUDE OF RELATIVES TO BEREAVMENT DUE TO COVID-19 IN NIGERIA
Creators: name: Idowu Oluwaseyi
name: Jokotola Prisca
name: Olorunleke Emmanuel Alebiosu
Publisher: name: figshare
Year: 2020
Subjects: subject: 111002 Clinical Nursing: Primary (Preventative)
subject: FOS: Health sciences
subject: 111004 Clinical Nursing: Tertiary (Rehabilitative)
subject: 160701 Clinical Social Work Practice
subject: FOS: Sociology
subject: Pathology

description: This paper seeks to evaluate the attitude of the mourning family of people who died due to complications of Covid-19. It seeks to understand their perspective on care plans and methods and processes leading to the end of life of their loved ones. It also considers legal implications and Nursing care.
title: Backstoptechnologie nach Technologiedurchbruch
Creators: name: Löffler, Philipp
Publisher: name: TU Wien
Year: 2018
Subjects: subject: Grünes Paradoxon
subject: Klimawandel
subject: Umweltpolitik
subject: Umweltsteuer
subject: Regimewechsel
subject: green paradox
subject: climate change
subject: enviromental policy
subject: carbon tax
subject: regime shift

description: Diese Arbeit wirft einen Blick auf die aktuelle Klimapolitik und ordnet sie aus ökonomischer Sicht ein. Sie bietet einen Überblick über die Theorie des grünen Paradoxon von Hans-Werner Sinn und einer Erweiterung von Frederick van der Ploeg. Ein monopolistischen Ressourcenbesitzer wird mit einer grünen Backstoptechnologie konfrontiert, welche zu einem zufälligem Zeitpunkt verfügbar wird. Dabei wird eine isoelastische Nachfragefunktion mit Explorationsinvestitionen zu Beginn anstatt von pro-Stück-Extraktionskosten angenommen. In Erweiterungen wird eine weitere Exploration zum Zeitpunkt des Technologiedurchbruchs sowie ein variabler Preis von erneuerbaren Energien angenommen. Der unsichere Zeitpunkt des Technologiedurchbruchs führt zu ineffizient schneller Extraktion und niedrigen Explorationsinvestitionen. Eine steigende Steuer oder Subventionierung der Backstoptechnologie erhöht die Abbaugeschwindigkeit und senkt die Explorationsinvestitionen. Der zweite Effekt kann ein grünes Paradoxon umkehren. Eine im Verhältnis zur ersten Exploration hohe zweite Exploration kann die Abbaugeschwindigkeit verlangsamen. Der sinkende Preis von erneuerbaren Energien führt zu schnellerer Extraktion.
description: This thesis is based on the theory of the Green Paradox by Hans-Werner Sinn and a paper by Frederick van der Ploeg. The investigations are about a monopolistic owner of oil reserves and his response to a green backstop technology, which becomes available at some uncertain point. An isoelastic demand function and an initial exploration investment instead of variable extraction costs are assumed. The model is extended by another exploration investment at the breakthrough and variable costs of renewables. Due to the uncertain timing of the breakthrough, the depletion rates are inefficiently high and the exploration investments are reduced. An increasing tax rate or subsidization of green R&D speeds up oil depletion and lowers the exploration investments. The latter effect can reverse the Green Paradox. If the second investment is - compared to the first investment - big enough, the speed of oil depletion can be reduced. The reduced costs of renewables speeds up the oil depletion.
Phase-field simulations of solidification in binary and ternary systems using a finite element method
Creators: name: Danilov, Denis
name: Nestler, Britta
Publisher: name: arXiv
Year: 2004
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We present adaptive finite element simulations of dendritic and eutectic solidification in binary and ternary alloys. The computations are based on a recently formulated phase-field model that is especially appropriate for modelling non-isothermal solidification in multicomponent multiphase systems. In this approach, a set of governing equations for the phase-field variables, for the concentrations of the alloy components and for the temperature has to be solved numerically, ensuring local entropy production and the conservation of mass and inner energy. To efficiently perform numerical simulations, we developed a numerical scheme to solve the governing equations using a finite element method on an adaptive non-uniform mesh with highest resolution in the regions of the phase boundaries. Simulation results of the solidification in ternary Ni$_{60}$Cu$_{40-x}$Cr$_{x}$ alloys are presented investigating the influence of the alloy composition on the growth morphology and on the growth velocity. A morphology diagram is obtained that shows a transition from a dendritic to a globular structure with increasing Cr concentrations. Furthermore, we comment on 2D and 3D simulations of binary eutectic phase transformations. Regular oscillatory growth structures are observed combined with a topological change of the matrix phase in 3D. An outlook for the application of our methods to describe AlCu eutectics is given.
description: 5 pages, 3 figures, To appear in the proceedings of 14th "International Conference on Crystal Growth", ICCG-14, 9-13 August 2004 Grenoble France
Electronic structure of the $Sr_{0.4}Ca_{13.6}Cu_{24}O_{41}$ incommensurate compound
Creators: name: Gelle, Alain
name: Lepetit, Marie-Bernadette
Publisher: name: arXiv
Year: 2004
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We extracted, from strongly-correlated ab-initio calculations, a complete model for the chain subsystem of the $Sr_{0.4}Ca_{13.6}Cu_{24}O_{41}$ incommensurate compound. A second neighbor $t-J+V$ model has been determined as a function of the fourth crystallographic parameter $τ$, for both low and room temperature crystallographic structures. The analysis of the obtained model shows the crucial importance of the structural modulations on the electronic structure through the on-site energies and the magnetic interactions. The structural distortions are characterized by their long range effect on the cited parameters that hinder the reliability of analyses such as BVS. One of the most striking results is the existence of antiferromagnetic nearest-neighbor interactions for metal-ligand-metal angles of $90^\circ$. A detailed analysis of the electron localization and spin arrangement is presented as a function of the chain to ladder hole transfer and of the temperature. The obtained spin arrangement is in agreement with antiferromagnetic correlations in the chain direction at low temperature.
Evaluation of energy generation potential from residues generated in a footwear industry
Creators: name: Souza, José De
name: Keli Fernanda Schonardie
name: Sinara Daiani Sander
Publisher: name: figshare
Year: 2020
Subjects: subject: 90799 Environmental Engineering not elsewhere classified
subject: FOS: Environmental engineering

description: The leather-footwear industry became responsible for the generation of a large amount of solidwaste, mostly received in landfills. However, this would be the final option for its disposal, exhausted allpossibilities for its reuse. In this scenario, there are alternatives for the treatment or reuse of these wastes such ascoprocessing, a non-commercial waste recovery process, which consists of the recovery and recycling of wastefor use as partial substitutes for the fuel and raw material in the process of production of cement (clinker).Incineration is a thermal waste treatment process and thermal hydrolysis consisting of the breaking of molecules that results in gelatin, which in the case of leather produces fertilizer. The heat generated allows its use as a form of production of electric energy and steam. This paper will present a study of the possible alternatives of waste disposal, with the objective of studying a way of transforming this waste into electric power generation, in order to be used by the companies of the footwear segment of the Paranhana valley region in RS, since the economy of this region revolves around this segment.
Nonabelian Poisson Manifolds from D-Branes
Creators: name: Isidro, J. M.
Publisher: name: arXiv
Year: 2004
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Superimposed D-branes have matrix-valued functions as their transverse coordinates, since the latter take values in the Lie algebra of the gauge group inside the stack of coincident branes. This leads to considering a classical dynamics where the multiplication law for coordinates and/or momenta, being given by matrix multiplication, is nonabelian. Quantisation further introduces noncommutativity as a deformation in powers of Planck's constant. Given an arbitrary simple Lie algebra and an arbitrary Poisson manifold, both finite-dimensional, we define a corresponding C*-algebra that can be regarded as a nonabelian Poisson manifold. The latter provides a natural framework for a matrix-valued classical dynamics.
"hep-data-NN-dataset.tar.bz2" of "Search for light long-lived neutral particles from Higgs boson decays via vector-boson-fusion production from $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector"
Creators: name: ATLAS Collaboration
Publisher: name: HEPData
Year: 2024

description: QCD tagger training samples
description: A search is reported for long-lived dark photons with masses between 0.1 and 15 GeV, from exotic decays of Higgs bosons produced via vector-boson-fusion. Events that contain displaced collimated Standard Model fermions reconstructed in the calorimeter or muon spectrometer are probed to search for long-lived dark photon candidates that then decay into collimated jets of leptons or light hadrons. This search uses the full LHC Run 2 (2015-2018) data sample collected in proton-proton collisions at $\sqrt{s}$=13 TeV, corresponding to an integrated luminosity of 139 fb$^{-1}$. Dominant backgrounds from Standard Model processes and non-collision sources are estimated by using data-driven techniques. The observed event yields in the signal regions are consistent with the expected background. Upper limits on the Higgs boson to dark photon branching fraction are reported as a function of the mean dark photon proper decay length, or as a function of the dark-photon mass and kinetic mixing parameter that quantifies the coupling between the Standard Model and potential dark sector. These limits are also combined with previous ATLAS results obtained in the gluon-gluon fusion and WH production modes. A branching fraction above 10% is excluded at 95% CL for a Higgs boson decaying into two dark photons for dark-photon mean proper decay lengths between 173 and 1296 mm and mass of 10 GeV.
Viability for the production of inorganic pigments from galvanic sludge
Creators: name: Becker, Julia
name: Selbach, Isabella C.
name: Souza, José De
name: Feliciane A. Brehm
Publisher: name: figshare
Year: 2020
Subjects: subject: 91299 Materials Engineering not elsewhere classified
subject: FOS: Materials engineering

description: The residue from the treatment of effluents from the galvanizing industries is called galvanic sludge and has potentially toxic metals in it. Incorrect disposal of galvanic sludge can cause damage to the environment and health. The work sought to evaluate the feasibility of using galvanic sludge in the production of inorganic pigments. Characterization of the residue was carried out using atomic absorption spectroscopy, X-ray fluorescence, moisture determination, sieve granulometry, fire loss, thermogravimetry, and differential thermal analysis. The results obtained bought the possibility of p production of pigments with galvanic sludge.
title: Modelling the major metabolic pathways of the eukaryotic cell: glycolysis, the citric-acid cycle, and oxidative phosphorylation
Creators: name: Hollan, Adam
Publisher: name: TU Wien
Year: 2018
Subjects: subject: simulation
subject: model
subject: glycolysis
subject: cell

description: In this study, a computer program was constructed, which models the main steps of energy production inside the cells of eukaryotic organisms. The sections of the cellular metabolic pathways considered here are glycolysis, the citric acid cycle, and oxidative phosphorylation. Together, these processes are responsible for the conversion of nutrients into chemical energy in, for example, human cells. The resulting computer model aims to be simple to use, while maintaining a considerable level of exibility to allow for customization. Adjustable parameters, such as enzyme kinetics and chemical values, as well as stochastic variables, make it possible to simulate a wide variety of biomedical scenarios. Models such as the one described here may nd use in clinical investigations, as there are several diseases that stem from a malfunctioning cell metabolism. Computer modeling has the potential to improve our understanding of such diseases and can support the assessment of eects that drugs or therapies have on these processes. Experimental results from previous studies were used for the construction and verication of the model. The simulations performed in this work were found to very closely match the behaviour described by the underlying research. The model behaved as expected when the evolution of intermediate concentrations, or its response to varying amounts of oxygen, have been examined. In the cancer model, reducing the activity of the enzyme hexokinase by 87% resulted in a halved energy production capability, compared to the 76% found in a previous study. Furthermore, a reduction of the glucose supply when simulating tumor cell conditions using this model produced a very realistic response when compared to in vivo results found in previous research.
The Farmers’ Calendar as an example of a cultural factor shaping the knowledge about the countryside and agriculture in Poland
Creators: name: Wójcik, Marcin
name: Wójcik, Marcin
Publisher: name: Unknown
Year: 2013
Subjects: subject: Community/Rural/Urban Development
subject: Labor and Human Capital
subject: Teaching/Communication/Extension/Profession
subject: knowledge
subject: cultural factors
subject: agriculture
subject: Poland

description: The modern scientific discourse on economic development increasingly emphasises the role of cultural factors. Social sciences reach for the cultural theories when they cannot explain the lack of economic growth despite favourable conditions, especially the financial and institutional ones. In Poland agriculture is the sector where the changes are strongly conditioned by the cultural background. Increasingly, the transformation of agriculture is broadly referred to the concept of "rurality". The study of modernisation of rural areas should take greater account of the cultural dimension (factors, determinants) and its influence over the economic transformation. A cultural perspective allows understanding the historicity of the countryside as a kind of the social survival which, whatever the prevailing economic trends, is based on certain values. Social scientists (sociologists, anthropologists, human geographers and other specialists) often criticise the perception of the peripheries as being economically backward and underdeveloped, especially in the context of the depreciation of the rural lifestyle. What is emphasised is the role of rural communities in fostering traditional values, including forms of cultural landscape, and their contribution to the phenomena shaping the modern mass (global) society. In recent years, the concept of "social representation", which uses qualitative methodology (mainly the analysis of visual and written materials), has become very popular.The paper presents The Farmers’ Calendar – a source of knowledge about agriculture addressed to farmers, which carries not only useful information but also a specific cultural transfer. This information is in fact embedded in the traditional cultural pattern, strongly associated with religious practices, the sphere of the family values and all the elements which stress the specific (magical and religious) dimension of the relation between a farmer and the nature. Although they cannot be regarded as the main source of knowledge about agriculture, these materials should be considered as an important expression of the cultural transmission and the way of thinking of a large group of people engaged in farming in Poland, especially in the eastern and southern regions of the country. The information from The Farmers’ Calendar was divided according to different criteria, including the volatility of the information over time (since the 1990s), the promoted interpretation of the vision of farmers’ work and the changes that have been taking place in the Polish agriculture.
Branch Rings, Thinned Rings, Tree Enveloping Rings
Creators: name: Bartholdi, Laurent
Publisher: name: arXiv
Year: 2004
Subjects: subject: Rings and Algebras (math.RA)
subject: Group Theory (math.GR)
subject: FOS: Mathematics

description: We develop the theory of ``branch algebras'', which are infinite-dimensional associative algebras that are isomorphic, up to taking subrings of finite codimension, to a matrix ring over themselves. The main examples come from groups acting on trees. In particular, for every field k we construct a k-algebra K which (1) is finitely generated and infinite-dimensional, but has only finite-dimensional quotients; (2) has a subalgebra of finite codimension, isomorphic to $M_2(K)$; (3) is prime; (4) has quadratic growth, and therefore Gelfand-Kirillov dimension 2; (5) is recursively presented; (6) satisfies no identity; (7) contains a transcendental, invertible element; (8) is semiprimitive if k has characteristic $\neq2$; (9) is graded if k has characteristic 2; (10) is primitive if k is a non-algebraic extension of GF(2); (11) is graded nil and Jacobson radical if k is an algebraic extension of GF(2).
description: 35 pages; small changes wrt previous version
The dynamic of agrifood systems and institutional impacts on Romanian vegetable producers
Creators: name: Alboiu, Cornelia
name: Toderoiu, Filon
name: Alboiu, Cornelia
name: Toderoiu, Filon
Publisher: name: Unknown
Year: 2013
Subjects: subject: Community/Rural/Urban Development
subject: Food Consumption/Nutrition/Food Safety
subject: International Relations/Trade
subject: institutions
subject: vegetable sector
subject: retail chains

description: The integration into the world trade and particularly along the chain of products with high value added, such as the vegetables chain, is considered as a promoter of growth and poverty alleviation (Aksoy and Beghin, 2005), even though this topic is subject to controversy. The paper’s purpose is to assess the role of collective organization forms in farmers’ participation in the Romanian supply chains, more exactly the possibility of farmers to adapt to the dynamic retail chains using new institutional economic theories. Having given the requirements imposed by retail chains to vegetable suppliers in terms of quantity, quality, frequency, food safety, it is expected that a small farmer cannot afford to participate individually in the retail chains due to high transaction costs, lack of scale and institutional changes required. In order to see the determinants of joining collective actions by vegetable producers, binary logit/probit models were used. The results signal out a small degree of farmers’ participation in collective forms of organizations. Also, they reveal a certain degree of uncertainty among stakeholders in terms of institutional arrangements and participation in collective action.
Phase transitions of pure and mixed organic and inorganic particles
Creators: name: Parsons, Matthew Timothy
Publisher: name: University of British Columbia
Year: 2010

description: Aerosol particles in the Earth’s atmosphere play a significant role in such aspects as health effects, visibility effects, and climate effects. In order to quantify the effects of aerosol particles, it is important to have a thorough understanding of the fundamental behavior of the particles. To address this issue, this thesis investigates the phase transitions of atmospherically relevant particles consisting of organic materials, mixed inorganic-organic materials, and inorganic materials with solid inclusions with a combination of techniques. Techniques used were optical microscopy of particles in a flow cell and optical microscopy of particles in an electrodynamic balance. Phase transitions studied were deliquescence and homogeneous and heterogeneous crystallization as functions of temperature, chemical composition, or particle size. The deliquescence relative humidity (RH) and crystallization RH results were interpreted at a fundamental level in terms of the underlying thermodynamic and kinetic factors that influence phase transitions of small particles. It was found that the deliquescence RH for the organic and mixed inorganic-organic particles could be predicted with reasonable accuracy with solution thermodynamics over the range of conditions studied. Homogeneous and heterogeneous nucleation rates were determined from crystallization RH results and parametrized [i.e. parameterized] in terms of classical nucleation theory. The atmospheric implications of the deliquescence RH and crystallization RH results are discussed, with attention to the extrapolation of deliquescence RH and crystallization RH values obtained in laboratory measurements to the expected deliquescence RH and crystallization RH of corresponding particles in atmospheric scenarios. For remote and urban regions of the atmosphere, the results suggest that the deliquescence RH of mixed inorganic-organic particles may be slightly decreased from the deliquescence RH of the pure inorganic material for the compositions studied. In contrast, crystallization RH results suggest that mixed inorganic-organic particles may crystallize at significantly lower RH than the crystallization RH of the pure inorganic materials for remote and urban regions. The heterogeneous crystallization results suggest that solid inclusions used in this study can influence the crystallization RH of inorganic particles in the atmosphere. This work provides extensive characterization of the phase transitions of atmospherically relevant particles, which can be used to improve the general understanding of the effects of aerosol particles in the Earth’s atmosphere.
Investigation of the Production Risks and Risk Mitigation Behaviour by Farmers in Northeastern Area of Central Trinidad
Creators: name: Browne, Antoinette
name: Pemberton, Carlisle
name: Browne, Antoinette
name: Pemberton, Carlisle
Publisher: name: Unknown
Year: 2011
Subjects: subject: Agribusiness
subject: Community/Rural/Urban Development
subject: Crop Production/Industries
subject: Production Economics
subject: Productivity Analysis
subject: Risk mitigation behaviour
subject: Socioeconomic characteristics of farmers
subject: logistic regression and sample selection analysis

description: Caribbean farmers are frequently bombarded by numerous production risks that not only negatively impact agricultural production, but agricultural development. Since these risks reduce agricultural production (IICA, 2006a) it is imperative that risk mitigation measures be employed to lessen the impact of risk on agricultural production. Production risks are considered by farmers to be some of the most important risks that significantly impact their livelihoods. There appears to be limited research done on the subject areas of production risks and risk behavior of farmers in Trinidad and by extension, the Caribbean. Therefore, this study seeks to identify and better understand the production risks and the risk behaviors of farmers in Trinidad. The study was conducted in seven districts of County Caroni and two districts of St. George West County, which span the northeastern area of central Trinidad. Data was collected from 227 farmers via the use of a questionnaire and field visits. Data analysis used frequency distributions, chi-square, logistic and sample selection regression models. The binary logistic regression technique was used to test the hypothesis that there is a relationship between the socioeconomic characteristics of farmers and the risk mitigation behavior of farmers. The sample selection technique was used to investigate the effects of various socioeconomic characteristics of farmers on the effectiveness of the risk mitigation measures practiced by the farmers. The results identified the following significant socioeconomic characteristics that affect risk mitigation; the time spent on the farm, age of farmer, farm size, tenure of the land, whether the farmers was the head of the household , whether the farmer cultivated crops , whether the farmer reared livestock and whether the farmer that was exposed to drought. The study has also revealed the following significant socioeconomic characteristics of farmers that determine the effectiveness of the risk mitigation measures implemented by these farmers; farm size, whether the farmer reared livestock, whether the farmer was exposed to floods and heavy rains, praedial larceny and drought.
Quantum many-body dynamics in a Lagrangian frame: II. Geometric formulation of time-dependent density functional theory
Creators: name: Tokatly, I. V.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We formulate equations of time-dependent density functional theory (TDDFT) in the co-moving Lagrangian reference frame. The main advantage of the Lagrangian description of many-body dynamics is that in the co-moving frame the current density vanishes, while the density of particles becomes independent of time. Therefore a co-moving observer will see the picture which is very similar to that seen in the equilibrium system from the laboratory frame. It is shown that the most natural set of basic variables in TDDFT includes the Lagrangian coordinate, $\bmξ$, a symmetric deformation tensor $g_{μν}$, and a skew-symmetric vorticity tensor, $F_{μν}$. These three quantities, respectively, describe the translation, deformation, and the rotation of an infinitesimal fluid element. Reformulation of TDDFT in terms of new basic variables resolves the problem of nonlocality and thus allows to regularly derive a local nonadiabatic approximation for exchange correlation (xc) potential. Stationarity of the density in the co-moving frame makes the derivation to a large extent similar to the derivation of the standard static local density approximation. We present a few explicit examples of nonlinear nonadiabatic xc functionals in a form convenient for practical applications.
description: RevTeX4, 18 pages, Corrected final version. The first part of this work is cond-mat/0408352
On `On the Red Supergiant Problem': a rebuttal, and a consensus on the upper mass cutoff for II-P progenitors
Creators: name: Davies, Ben
name: Beasor, Emma
Publisher: name: arXiv
Year: 2020
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The `Red Supergiant Problem' describes the claim that the brightest Red Supergiant (RSG) progenitors to type II-P supernovae are significantly fainter than RSGs in the field. This mismatch has been interpreted by several authors as being a manifestation of the mass threshold for the production of black holes (BHs), such that stars with initial masses above a cutoff of $M_{\rm hi}=17$M$_\odot$ and below 25$M_\odot$ will die as RSGs, but with no visible SN explosion as the BH is formed. However, we have previously cautioned that this cutoff is more likely to be higher and has large uncertainties ($M_{\rm hi}=19^{+4}_{-2}M_{\odot}$), meaning that the statistical significance of the RSG Problem is less than $2σ$. Recently, Kochanek (2020) has claimed that our work is statistically flawed, and with their analysis has argued that the upper mass cutoff is as low as $M_{\rm hi} = 15.7 \pm 0.8M_\odot$, giving the RSG Problem a significance of $>10σ$. In this letter, we show that Kochanek's low cutoff is caused by a statistical misinterpretation, and the associated fit to the progenitor mass spectrum can be ruled out at the 99.6\% confidence level. Once this problem is remedied, Kochanek's best fit becomes $M_{\rm hi} =19^{+4}_{-2}M_{\odot}$, in excellent agreement with our work. Finally, we argue that, in the search for a RSG `vanishing' as it collapses directly to a BH, any such survey would have to operate for decades before the absence of any such detection became statistically significant.
description: 5 pages, 5 figures, accepted for publication in MNRAS
Difference Discrete Variational Principle in Discrete Mechanics and Symplectic Algorithm
Creators: name: Luo, Xu-Dong
name: Guo, Han-Ying
name: Li, Yu-Qi
name: Wu, Ke
Publisher: name: arXiv
Year: 2004
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We propose the difference discrete variational principle in discrete mechanics and symplectic algorithm with variable step-length of time in finite duration based upon a noncommutative differential calculus established in this paper. This approach keeps both symplicticity and energy conservation discretely. We show that there exists the discrete version of the Euler-Lagrange cohomology in these discrete systems. We also discuss the solution existence in finite time-length and its site density in continuous limit, and apply our approach to the pendulum with periodic perturbation. The numerical results are satisfactory.
description: 18 pages, 3 figures
Caribbean Restaurants in the U.S.: Applying GIS to Show Market Potential
Creators: name: Estwick, N. M.
name: Ojumu, O. A.
name: Richards, F. L.
name: Estwick, N. M.
name: Ojumu, O. A.
name: Richards, F. L.
Publisher: name: Unknown
Year: 2011
Subjects: subject: International Development
subject: International Relations/Trade
subject: Marketing
subject: FOS: Economics and business
subject: Production Economics
subject: Productivity Analysis
subject: Market potential
subject: GIS for market analysis
subject: Caribbean restaurants in the USA
subject: full-service restaurants

description: The number of people of Caribbean origin travelling and residing in the United States of America (USA) has been on the increase in recent decades. In addition, Caribbean countries continue to be attractive vacation destinations for Americans. Consequently, a large number of persons in the USA are potential consumers of Caribbean foods. A United States Department of Agriculture, Economic Research Service (USDA-ERS) report (2004) revealed that the USA market increase in demand for food away from home grew in the last decade of the 20th century and is expected to continue into the 21st century. The report outlined that the increased growth is expected at both fast food restaurants and full-service restaurants. Also, it is projected that between 2000 and 2020, the growth in household income and demographic developments are expected to result 18 percent increase in spending at full-service restaurants and 6 percent increase in spending at fast food restaurants (USDA-ERS, 2004). While the current and expected increase in demand within the USA food away from home market creates a potential market for Caribbean restaurants, it also presents Caribbean restaurant operators with the challenge of determining the market potential for their food establishments. Market potential analysis provides information on available business opportunities in geographic regions. The authors hypothesize that Geographic Information Systems (GIS) is an ideal tool for conducting market potential analysis and aiding with decision making. This research employed the use of GIS to map Caribbean restaurants located in the continental USA, and a variety of spatial analysis tools from the Environmental Research Institute (ESRI) ArcMap 9.3 software to analyze and map potential markets for Caribbean restaurants. Population size, demographics and median income data obtained from the U.S. Census Bureau website were used to conduct the spatial analysis. Away from home food expenditures data was also used to support the results. The results suggest that GIS is an ideal tool for conducting market analysis. Furthermore, it can aid with decision making for identification of areas that are potentially suitable for targeting the location of Caribbean restaurants based on the selected variables.
Evaluation of the space holder technique for processing of porous titanium as biomaterial
Creators: name: Ronei Tochetto
name: Tochetto, Rafael
name: Biehl, Luciano Volcanoglo
name: Medeiros, Jorge Luis Braz
name: Josimar Cândido Dos Santos
name: Souza, José De
Publisher: name: figshare
Year: 2020
Subjects: subject: 91299 Materials Engineering not elsewhere classified
subject: FOS: Materials engineering

description: The objective of this paper is the manufacture of a porous metal structure from commercially pure titanium powder grade 1, aiming at the possible application as a biomaterial in the regeneration of bone tissues assuming its architecture. Experimental methods were used to evaluate the effectiveness of the use of the space holder technique in the manufacture of powder metallurgy (MP). In the samples produced, 50% by volume of titanium powder and 50% of chemical reagent (Sodium Chloride - NaCl and Ammonium Bicarbonate - HN4HCO3) were added, compressed with a pressure of 250 Mpa. The metal-only test samples were compacted with pressures of 70 MPa and 250 MPa. The architecture found with the use of space holder was satisfactory, presenting sufficient conditions of size, morphology, and interconnectivity for bone growth within the structure. Samples made only with metal powder do not have enough pores even with lower compation pressure.
Direct Observation of Controlled Coupling in an Individual Quantum Dot Molecule
Creators: name: Krenner, H. J.
name: Sabathil, M.
name: Clark, E. C.
name: Kress, A. F.
name: Schuh, D.
name: Bichler, M.
name: Abstreiter, G.
name: Finley, J. J.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We report the direct observation of quantum coupling in individual quantum dot molecules and its manipulation using static electric fields. A pronounced anti-crossing of different excitonic transitions is observed as the electric field is tuned. Comparison of our experimental results with theory shows that the observed anti-crossing occurs between excitons with predominant spatially \emph{direct} and \emph{indirect} character. The electron component of the exciton wavefunction is shown to have molecular character at the anti-crossing and the quantum coupling strength is deduced optically. In addition, we determine the dependence of the coupling strength on the inter-dot separation and identify a field driven transition of the nature of the molecular ground state.
description: 11 pages, 4 figures submitted to Physical Review Letters
Evaluation of alternative fuel for the generation of thermal energy through a boiler
Creators: name: Schafer, Alex
name: Scherer, Fernando
name: Souza, José De
Publisher: name: figshare
Year: 2020
Subjects: subject: 91305 Energy Generation, Conversion and Storage Engineering
subject: FOS: Mechanical engineering

description: This paper aims to compare fuel alternatives to a boiler used for steam generation. Among the options compatible with the boiler model used by the company, the fuel options were firewood of Acacia decurrens, Eucalyptus globulus, Pinus taeda or Pinus elliottii and dry biomass. There was the cost versus calorific value of the alternatives found, and the wood of Acacia decurrens is the fuel that has the lowest price.