913 resultados para Independant entity
Resumo:
Tutkielmassa tarkastellaan kuluttajien näkemyksiä ilmastonmuutoksesta ja ilmastovaikutusten seuranta- ja palautejärjestelmän hyväksyttävyydestä kulutuksen ohjauskeinona. 15 kuluttajaa kokeili kuukauden ajan kulutuksen ilmastovaikutusten seuranta- ja palautejärjestelmän demonstraatioversiota ja he osallistuivat kokeilun pohjalta aihepiiriä käsitelleeseen verkkokeskusteluun. Analysoin verkkokeskustelun aineistoa arkisen järkeilyn näkökulmasta tutkien kuluttajien ilmastonmuutokseen ja ympäristövastuullisuuteen liittyvää arkitietoa sekä palvelun hyväksyttävyyteen liittyviä heuristiikkoja. Ilmastonmuutoksen todettiin yleisesti olevan vielä melko abstrakti ja monitulkintainen ilmiö, minkä vuoksi kuluttajilla on vaikeuksia ymmärtää omien valintojensa konkreettista merkitystä ilmastonmuutoksen kannalta. Vaikka tietoa kulutuksen ilmastovaikutuksista on saatavilla paljon, niin erityisesti yritysten tuottama tieto koettiin ristiriitaiseksi ja osin epäluotettavaksi. Kuluttajat myös kritisoivat ilmastonmuutoskeskustelun tarjoamaa kapeaa näkemystä kulutuksen ympäristövaikutuksista. Hiilidioksidipäästöihin keskittymisen sijaan ympäristövaikutuksia tulisi kuluttajien mielestä tarkastella kokonaisuutena, josta ilmastovaikutukset muodostavat vain yhden osan. Tutkimukseen osallistuneiden kuluttajien kulutustottumuksiin ilmastonmuutos vaikutti eriasteisesti. Toisille ilmastonmuutoksesta oli muodostunut keskeinen omaa kulutusta ohjaava normi, kun taas toiset kertoivat pohtivansa ilmastovaikutuksia pääasiassa suurimpien hankintojen kohdalla. Ympäristövastuullisuudessa merkitykselliseksi koettiin tasapainon löytäminen ja henkilökohtainen tunne siitä, että kokee toimivansa oikein. Ilmasto- tai ympäristökysymyksiä punnitaan valinnoissa joustavasti yhdessä muiden tekijöiden kanssa. Vaikka kuluttajilla toisaalta olisi tietoa ja halua ottaa ilmasto- ja ympäristövaikutukset huomioon valinnoissaan, toimintaympäristö rajaa keskeisesti kuluttajien mahdollisuuksia toimia ympäristövastuullisesti. Tutkimus toi esille neljä kuluttajien käyttämää heuristiikkaa heidän pohtiessaan ilmastovaikutusten seuranta- ja palautejärjestelmän hyväksyttävyyden ehtoja ja toimivuutta ohjauskeinona. Ensinnäkin palvelun tulee olla käytettävyydeltään nopea ja vaivaton sekä tarjota tietoa havainnollisessa ja helposti ymmärrettävässä muodossa. Toiseksi palvelun tarjoaman tiedon tulee olla ehdottoman luotettavaa ja kuluttajien valintojen kannalta merkityksellistä siten, että palvelu ottaa huomioon erilaiset kuluttajat ja tiedontarpeet. Kolmanneksi palvelu tulee toteuttaa kokonaisvaltaisesti ja läpinäkyvästi useampien kaupparyhmittymien ja julkisten toimijoiden yhteistyönä. Neljänneksi toteutuksessa tulee huomioda palvelun kannustavuus ja kytkeytyminen muihin ohjauskeinoihin.
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The protein kinases (PKs) belong to the largest single family of enzymes, phosphotransferases, which catalyze the phosphorylation of other enzymes and proteins and function primarily in signal transduction. Consequently, PKs regulate cell mechanisms such as growth, differentiation, and proliferation. Dysfunction of these cellular mechanisms may lead to cancer, a major predicament in health care. Even though there is a range of clinically available cancer-fighting drugs, increasing number of cancer cases and setbacks such as drug resistance, constantly keep cancer research active. At the commencement of this study an isophthalic acid derivative had been suggested to bind to the regulatory domain of protein kinase C (PKC). In order to investigate the biological effects and structure-activity relationships (SARs) of this new chemical entity, a library of compounds was synthesized. The best compounds induced apoptosis in human leukemia HL-60 cells and were not cytotoxic in Swiss 3T3 fibroblasts. In addition, the best apoptosis inducers were neither cytotoxic nor mutagenic. Furthermore, results from binding affinity assays of PKC isoforms revealed the pharmacophores of these isophthalic acid derivatives. The best inhibition constants of the tested compounds were measured to 210 nM for PKCα and to 530 nM for PKCδ. Among natural compounds targeting the regulatory domain of PKC, the target of bistramide A has been a matter of debate. It was initially found to activate PKCδ; however, actin was recently reported as the main target. In order to clarify and to further study the biological effects of bistramide A, the total syntheses of the natural compound and two isomers were performed. Biological assays of the compounds revealed accumulation of 4n polyploid cells as the primary mode of action and the compounds showed similar overall antiproliferative activities. However, each compound showed a distinct distribution of antimitotic effect presumably via actin binding, proapoptotic effect presumably via PKCδ, and pro-differentiation effect as evidenced by CD11b expression. Furthermore, it was shown that the antimitotic and proapoptotic effects of bistramide A were not secondary effects of actin binding but independent effects. The third aim in this study was to synthesize a library of a new class of urea-based type II inhibitors targeted at the kinase domain of anaplastic lymphoma kinase (ALK). The best compounds in this library showed IC50 values as low as 390 nM for ALK while the initial low cellular activities were successfully increased even by more than 70 times for NPM-ALK- positive BaF3 cells. More importantly, selective antiproliferative activity on ALK-positive cell lines was achieved; while the best compound affected the BaF3 and SU-DHL-1 cells with IC50 values of 0.5 and 0.8 μM, respectively, they were less toxic to the NPM-ALK-negative human leukemic cells U937 (IC50 = 3.2 μM) and BaF3 parental cells (IC50 = 5.4 μM). Furthermore, SAR studies of the synthesized compounds revealed functional groups and positions of the scaffold, which enhanced the enzymatic and cellular activities.
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Relying on Merleau-Ponty's phenomenology of perception and on Mircea Eliade's works on the Sacred and the Profane, this study explores the river as a perceptual space and as the sacred Center in a cosmic vision of the world in twelve of Jean-Marie Gustave Le Clézio's fictional works, from The Interrogation (1963) to Revolutions (2003). In the first chapter, after introducing the field of study, I discuss the relation between the radical subjectivity and the evasiveness of perceiving subjects in Le Clézio's fiction. Next are some thoughts on the relation between Merleau-Ponty's and Le Clézio's ideas. The second chapter studies the river as an experience in the text, first as a topographical space, then as a sound world. The investigations move on to its water as a visual and a tactile phenomenon. Then follows the human use of the river, the (absence of) baths, and the river as a traveling space. The chapter closes with the study of the metaphorical use of the word, occurring mainly in urban space and for phenomena in the sky. The third chapter is organized around the river as the Center of the world in a religious cosmogony, where the river represents the origin of the world and of the human race. The core analysis shows how the middle of the river is a symbolic space of a new beginning. As a sacred space, the river abolishes time as the object of contemplation and as relative immobility from the point of view of a person drifting downstream. The functions of a new beginning and of abolition of time are combined in the symbolic immersions in the water. Finally, the dissertation explores other symbolical spaces, such as the unknown destination of the drift, and the river as the Center of a utopia. The chapter closes with the existential agony as a result of the elimination of the Center in the urban environment. In the final chapter, the river is compared to other watercourses : the creek, the brook and the rapids. The river is more of a spatial entity, whereas the actual water is more important in the smaller watercourses. The river is more common than the other watercourses as a topographical element in the landscape, whereas the minor watercourses invite the characters to a closer contact with their element, in immersions and in drinking their water. Finally, the work situates the rivers in a broader context of different fictional spaces in Le Clézio's text.
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In this dissertation I study language complexity from a typological perspective. Since the structuralist era, it has been assumed that local complexity differences in languages are balanced out in cross-linguistic comparisons and that complexity is not affected by the geopolitical or sociocultural aspects of the speech community. However, these assumptions have seldom been studied systematically from a typological point of view. My objective is to define complexity so that it is possible to compare it across languages and to approach its variation with the methods of quantitative typology. My main empirical research questions are: i) does language complexity vary in any systematic way in local domains, and ii) can language complexity be affected by the geographical or social environment? These questions are studied in three articles, whose findings are summarized in the introduction to the dissertation. In order to enable cross-language comparison, I measure complexity as the description length of the regularities in an entity; I separate it from difficulty, focus on local instead of global complexity, and break it up into different types. This approach helps avoid the problems that plagued earlier metrics of language complexity. My approach to grammar is functional-typological in nature, and the theoretical framework is basic linguistic theory. I delimit the empirical research functionally to the marking of core arguments (the basic participants in the sentence). I assess the distributions of complexity in this domain with multifactorial statistical methods and use different sampling strategies, implementing, for instance, the Greenbergian view of universals as diachronic laws of type preference. My data come from large and balanced samples (up to approximately 850 languages), drawn mainly from reference grammars. The results suggest that various significant trends occur in the marking of core arguments in regard to complexity and that complexity in this domain correlates with population size. These results provide evidence that linguistic patterns interact among themselves in terms of complexity, that language structure adapts to the social environment, and that there may be cognitive mechanisms that limit complexity locally. My approach to complexity and language universals can therefore be successfully applied to empirical data and may serve as a model for further research in these areas.
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At the the heart of this study can be seen the dual concern of how the nation is represented as a categorical entity and how this is put to use in everyday social interactions.This can be seen as a reaction to the general approach to categorisation and identity functions that tend to be reified and essentialized within the social sciences. The empirical focus of this study is the Isle of Man, a crown dependency situated geographically central within the British Isles while remaining political outside the United Kingdom. The choice of this site was chosen explicitly as ‘notions of nation’ expressed on the island can be seen as being contested and ephemerally unstable. To get at these ‘notions of nation’ is was necessary to choose specific theoretical tools that were able to capture the wider cultural and representational domain while being capable of addressing the nuanced and functional aspects of interaction. As such, the main theoretical perspective used within this study was that of critical discursive psychology which incorporates the specific theoretical tools interpretative repertoires, ideological dilemmas and subject positions. To supplement these tools, a discursive approach to place was taken in tandem to address the form and function of place attached to nationhood. Two methods of data collection were utilized, that of computer mediated communication and acquaintance interviews. From the data a number of interpretative repertoires were proposed, namely being, essential rights, economic worth, heritage claims, conflict orientation, people-as-nation and place-as-nation. Attached to such interpretative repertoires were the ideological dilemmas region vs. country, people vs. place and individualism vs. collectivism. The subject positions found are much more difficult to condense, but the most significant ones were gender, age and parentage. The final focus of the study, that of place, was shown to be more than just an unreflected on ‘container’ of people but was significant in terms of the rhetorical construction of such places for how people saw themselves and the discursive function of the particular interaction. As such, certain forms of place construction included size, community, temporal, economic, safety, political and recognition. A number of conclusions were drawn from the above which included, that when looking at nation categories we should take into account the specific meanings that people attach to such concepts and to be aware of the particular uses they are put to in interaction. Also, that it is impossible to separate concepts neatly, but it is necessary to be aware of the intersection where concepts cross, and clash, when looking at nationhood.
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Conditions for the preparation of stoichiometric barium zirconyl oxalate heptahydrate (BZO) have been standardized. The thermal decomposition of BZO has been investigated employing TG, DTG and DTA techniques and chemical and gas analysis. The decomposition proceeds through four steps and is not affected much by the surrounding gas atmosphere. Both dehydration and oxalate decomposition take place in two steps. The formation of a transient intermediate containing both oxalate and carbonate groups is inferred. The decomposition of oxalate groups results in a carbonate of composition Ba2Zr2OsCO3, which decomposes between 600 and 800 ~ and yields barium zirconate. Chemical analysis, IR spectra and X-ray powder diffraction data support the identity of the intermediate as a separate entity.
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Conditions for the preparation of stoichiometric barium zirconyl oxalate heptahydrate (BZO) have been standardized. The thermal decomposition of BZO has been investigated employing TG, DTG and DTA techniques and chemical and gas analysis. The decomposition proceeds through four steps and is not affected much by the surrounding gas atmosphere. Both dehydration and oxalate decomposition take place in two steps. The formation of a transient intermediate containing both oxalate and carbonate groups is inferred. The decomposition of oxalate groups results in a carbonate of composition Ba2Zr2O5CO3, which decomposes between 600 and 800° and yields barium zirconate. Chemical analysis, IR spectra and X-ray powder diffraction data support the identity of the intermediate as a separate entity.Die Bedingungen für die Herstellung von stöchiometrischem Barium-zirconyl-oxalat Heptahydrat (BZO) wurden standardisiert. Die thermische Zersetzung von BZO wurde unter Einsatz der TG-, DTG- und DTA, sowie der chemischen und Gasanalyse untersucht. Die Zersetzung verläuft über vier Stufen und wird von der umgebenden Gasathmosphäre nicht besonders beeinflusst. Sowohl die Dehydratisierung als auch die Oxalatzersetzung erfolgt in zwei Stufen. Die Bildung einer intermediären Übergangsverbindung mit sowohl Oxalat- als auch Carbonatgruppen wirken hierbei mit. Die Zersetzung der Oxalatgruppen ergibt ein Carbonat der Zusammensetzung Ba2Zr2O5CO3, das zwischen 600 und 800° zersetzt wird und Bariumzirconat ergibt. Die Angaben der chemischen Analyse, der IR-Spekren und der Röntgen-Pulver-Diffraktion unterstützen die Identität der Intermediärverbindung als eine separate Einheit.On a standardisé les conditions de préparation de l'oxalate heptahydraté de zirconyle et de baryum (BZO) stoechiométrique. On a étudié la décomposition thermique de BZO par TG, TGD et ATD ainsi que par analyses chimiques et analyses des gaz. La décomposition a lieu en quatre étapes et n'est pas trop influencée par l'atmosphère ambiante. La déshydratation et la décomposition de l'oxalate ont lieu en deux étapes. Il se forme un composé intermédiaire de transition contenant à la fois les groupes oxalate et carbonate. La décomposition des groupes oxalate fournit un carbonate de composition Ba2Zr2O5CO3 qui se décompose entre 600 et 800° pour fournir du zirconate de baryum. L'analyse chimique, les spectres IR et la diffraction des rayons X sur poudre, apportent les preuves de l'existence d'un composé intermédiaire comme entité séparée.
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The aim of this thesis was to examine the understanding of community in George Lindbeck s The Nature of Doctrine. Intrinsic to this question was also examining how Lindbeck understands the relation between the text and the world which both meet in a Christian community. Thirdly this study also aimed at understanding what the persuasiveness of this understanding depends on. The method applied for this task was systematic analysis. The study was conducted by first providing an orientation into the nontheological substance of the ND which was assumed useful with respect to the aim of this study. The study then went on to explore Lindbeck in his own context of postliberal theology in order to see how the ND was received. It also attempted to provide a picture of how the ND relates to Lindbeck as a theologian. The third chapter was a descriptive analysis into the cultural-linguistic perspective, which is understood as being directly proportional to his understanding of community. The fourth chapter was an analysis into how the cultural-linguistic perspective sees the relation between the text and the world. When religion is understood from a cultural-linguistic perspective, it presents itself as a cultural-linguistic entity, which Lindbeck understands as a comprehensive interpretive scheme which structures human experience and understanding of oneself and the world in which one lives. When one exists in this entity, it is the entity which shapes the subjectivities of all those who are at home in this entity which makes participation in the life of a cultural linguistic entity a condition for understanding it. Religion is above all an external word that moulds and shapes our religious existence and experience. Understanding faith then as coming from hearing, is something that correlates with the cultural-linguistic depiction of reality. Religion informs us of a religious reality, it does not originate in any way from ourselves. This externality linked to the axiomatic nature of religion is also something that distinguishes Lindbeck sharply from liberalist tendencies, which understand religion as ultimately expressing the prereflective depths of the inner self. Language is the central analogy to understanding the medium in which one moves when inhabiting a cultural-linguistic system because language is the transmitting medium in which the cultural-linguistic system is embodied. The realism entailed in Lindbeck s understanding of a community is that we are fundamentally on the receiving end when it comes to our identities whether cultural or religious. We always witness to something. Its persuasiveness rests on the fact that we never exist in an unpersuaded reality. The language of Christ is a self-sustaining and irreducible cultural-linguistic entity, which is ontologically founded upon Christ. It transmits the reality of a new being. The basic relation to the world for a Christian is that of witnessing salvation in Christ: witnessing Christ as the home of hearing the message of salvation, which is the God-willed way. Following this logic, the relation of the world and the text is one of relating to the world from the text, i.e. In Christ through the word (text) for the world, because it assumes it s logic from the way Christ ontologically relates to us.
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Right as an Argument. Leo Mechelin and the Finnish Question 1886-1912 At the turn of the 20th century the Finnish Question rose up as a political and juridical issue at the international arena. The vaguely précised position of Finland in the Russian empire led to diverse conclusions concerning the correctness of the February manifesto of 1899. It was predominantly among a European elite of politicians, cultural workers and academics the issue rose some interest. Finns were active making propaganda for their cause, and they put an emphasis on the claim that the right was on the Finnish side. In the study Elisabeth Stubb compare the Finnish, Russian and European statements about the Finnish Question and analyse their use of right as an argument. The Finnish Question offers at the same time a case study of a national entity which possesses a political sphere of life but is not fully independent, and its possibilities to drive its interests in an international context. Leo Mechelin (1839-1914), the leader of the Finnish propaganda organization abroad, is used as a point of departure. The biographical stance is formed into a triangle, where Leo Mechelin, the idea of right and the Finnish Question abroad are the three cornerstones. The treatment of one cornerstone sheds a ligth on the two others. The metaphor of triangulation also worked as a method to reach "a third stance" in a scinetific and political issue that usually is polarised into two opposite alternatives. An adherence to a strict legal right could not in the end offer a complete, unquestionable and satisfactory solution to the Finnsih Question, it was dependent on "the right of state wisdom and sound insight". The Finnish propaganda abroad used almost completely alternative ways of making politics. The propaganda did not have a decisive effect on countries' official politics, but gained unofficial support, especially in the public opinion and in academic statements. Mechelin claimed that the political field was dependent on public opinion and scientific research. Together with the official politics these two fields formed a triangle that shared the task of balancing the political arena and preventing it from making unwise decisions of taking an unjust turn. The international sphere worked as a balancing part in the Finnish Question. Mechelin tried by claiming the status of state for Finland's part to secure the country a place at the official international arena. At the same time, and especially when the claim was not fully adopted, he emphasised, and in a European context worked for, that right would become the guiding light not only for international relations, but also for the policy making in the inner life of the state.
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The progressive myoclonic epilepsies (PMEs) are a clinically and etiologically heterogeneous group of symptomatic epilepsies characterized by myoclonus, tonic-clonic seizures, psychomotor regression and ataxia. Different disorders have been classified as PMEs. Of these, the group of neuronal ceroid lipofuscinoses (NCLs) comprise an entity that has onset in childhood, being the most common cause of neurodegeneration in children. The primary aim of this thesis was to dissect the molecular genetic background of patients with childhood onset PME by studying candidate genes and attempting to identify novel PME-associated genes. Another specific aim was to study the primary protein properties of the most recently identified member of the NCL-causing proteins, MFSD8. To dissect the genetic background of a cohort of Turkish patients with childhood onset PME, a screen of the NCL-associated genes PPT1, TPP1, CLN3, CLN5, CLN6, MFSD8, CLN8 and CTSD was performed. Altogether 49 novel mutations were identified, which together with 56 mutations found by collaborators raised the total number of known NCL mutations to 364. Fourteen of the novel mutations affect the recently identified MFSD8 gene, which had originally been identified in a subset of mainly Turkish patients as the underlying cause of CLN7 disease. To investigate the distribution of MFSD8 defects, a total of 211 patients of different ethnic origins were evaluated for mutations in the gene. Altogether 45 patients from nine different countries were provided with a CLN7 molecular diagnosis, denoting the wide geographical occurrence of MFSD8 defects. The mutations are private with only one having been established by a founder-effect in the Roma population from the former Czechoslovakia. All mutations identified except one are associated with the typical clinical picture of variant late-infantile NCL. To address the trafficking properties of MFSD8, lysosomal targeting of the protein was confirmed in both neuronal and non-neuronal cells. The major determinant for this lysosomal sorting was identified to be an N-terminal dileucine based signal (9-EQEPLL-14), recognized by heterotetrameric AP-1 adaptor proteins, suggesting that MFSD8 takes the direct trafficking pathway en route to the lysosomes. Expression studies revealed the neurons as the primary cell-type and the hippocampus and cerebellar granular cell layer as the predominant regions in which MFSD8 is expressed. To identify novel genes associated with childhood onset PME, a single nucleotide polymorphism (SNP) genomewide scan was performed in three small families and 18 sporadic patients followed by homozygosity mapping to determine the candidate loci. One of the families and a sporadic patient were positive for mutations in PLA2G6, a gene that had previously been shown to cause infantile neuroaxonal dystrophy. Application of next-generation sequencing of candidate regions in the remaining two families led to identification of a homozygous missense mutation in USP19 for the first and TXNDC6 for the second family. Analysis of the 18 sporadic cases mapped the best candidate interval in a 1.5 Mb region on chromosome 7q21. Screening of the positional candidate KCTD7 revealed six mutations in seven unrelated families. All patients with mutations in KCTD7 were reported to have early onset PME, rapid disease progression leading to dementia and no pathologic hallmarks. The identification of KCTD7 mutations in nine patients and the clinical delineation of their phenotype establish KCTD7 as a gene for early onset PME. The findings presented in this thesis denote MFSD8 and KCTD7 as genes commonly associated with childhood onset symptomatic epilepsy. The disease-associated role of TXNDC6 awaits verification through identification of additional mutations in patients with similar phenotypes. Completion of the genetic spectrum underlying childhood onset PMEs and understanding of the gene products functions will comprise important steps towards understanding the underlying pathogenetic mechanisms, and will possibly shed light on the general processes of neurodegeneration and nervous system regulation, facilitating the diagnosis, classification and possibly treatment of the affected cases.
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The anomalous X-ray scattering (AXS) method using Cu and Mo K absorption edges has been employed for obtaining the local structural information of superionic conducting glass having the composition (CuI)(0.3)(Cu2O)(0.35)(MoO3)(0.35). The possible atomic arrangements in near-neighbor region of this glass were estimated by coupling the results with the least-squares analysis so as to reproduce two differential intensity profiles for Cu and Mo as well as the ordinary scattering profile. The coordination number of oxygen around Mo is found to be 6.1 at the distance of 0.187 nm. This implies that the MoO6 octahedral unit is a more probable structural entity in the glass rather than MoO4 tetrahedra which has been proposed based on infrared spectroscopy. The pre-peak shoulder observed at about 10 nm(-1) may be attributed to density fluctuation originating from the MoO6 octahedral units connected with the corner sharing linkage, in which the correlation length is about 0.8 nm. The value of the coordination number of I- around Cu+ is estimated as 4.3 at 0.261 nm, suggesting an arrangement similar to that in molten CuI.
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The anomalous X-ray scattering (AXS) method using Mo K absorption edges has been employed for obtaining the local structural information of superionic conducting glass having the composition (AgI)(0.6)(Ag2MoO4)(0.4). The possible atomic arrangements in the near-neighbor region of this glass were estimated by coupling the results with the least-squares variational analysis so as to reproduce the differential intensity profile for Mo as well as the ordinary scattering profile. The coordination number of oxygen around Mo is found to be about 4 at the distance of 0.180 mn. This implies that the most probable structural entity in the glass is the MoO4 tetrahedral unit which has been proposed based on infrared spectroscopy. The value of the coordination number of I- around Ag+ is estimated as 4.4 at 0.287 nm, suggesting an arrangement similar to that of crystalline or molten AgI.
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We address the problem of allocating a single divisible good to a number of agents. The agents have concave valuation functions parameterized by a scalar type. The agents report only the type. The goal is to find allocatively efficient, strategy proof, nearly budget balanced mechanisms within the Groves class. Near budget balance is attained by returning as much of the received payments as rebates to agents. Two performance criteria are of interest: the maximum ratio of budget surplus to efficient surplus, and the expected budget surplus, within the class of linear rebate functions. The goal is to minimize them. Assuming that the valuation functions are known, we show that both problems reduce to convex optimization problems, where the convex constraint sets are characterized by a continuum of half-plane constraints parameterized by the vector of reported types. We then propose a randomized relaxation of these problems by sampling constraints. The relaxed problem is a linear programming problem (LP). We then identify the number of samples needed for ``near-feasibility'' of the relaxed constraint set. Under some conditions on the valuation function, we show that value of the approximate LP is close to the optimal value. Simulation results show significant improvements of our proposed method over the Vickrey-Clarke-Groves (VCG) mechanism without rebates. In the special case of indivisible goods, the mechanisms in this paper fall back to those proposed by Moulin, by Guo and Conitzer, and by Gujar and Narahari, without any need for randomization. Extension of the proposed mechanisms to situations when the valuation functions are not known to the central planner are also discussed. Note to Practitioners-Our results will be useful in all resource allocation problems that involve gathering of information privately held by strategic users, where the utilities are any concave function of the allocations, and where the resource planner is not interested in maximizing revenue, but in efficient sharing of the resource. Such situations arise quite often in fair sharing of internet resources, fair sharing of funds across departments within the same parent organization, auctioning of public goods, etc. We study methods to achieve near budget balance by first collecting payments according to the celebrated VCG mechanism, and then returning as much of the collected money as rebates. Our focus on linear rebate functions allows for easy implementation. The resulting convex optimization problem is solved via relaxation to a randomized linear programming problem, for which several efficient solvers exist. This relaxation is enabled by constraint sampling. Keeping practitioners in mind, we identify the number of samples that assures a desired level of ``near-feasibility'' with the desired confidence level. Our methodology will occasionally require subsidy from outside the system. We however demonstrate via simulation that, if the mechanism is repeated several times over independent instances, then past surplus can support the subsidy requirements. We also extend our results to situations where the strategic users' utility functions are not known to the allocating entity, a common situation in the context of internet users and other problems.
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The local structural information in the near-neighbor region of superionic conducting glass (AgBr)0.4(Ag2O)0.3(GeO2)0.3 has been estimated from the anomalous X-ray scattering (AXS) measurements using Ge and Br K absorption edges. The possible atomic arrangements in the near-neighbor region of this glass were obtained by coupling the results with the least-squares variational method so as to reproduce two differential intensity profiles for Ge and Br as well as the ordinary scattering profile. The coordination number of oxygen around Ge is found to be 3.6 at a distance of 0.176 nm, suggesting the GeO4 tetrahedral unit as the probable structural entity in this glass. Moreover, the coordination number of Ag around Br is estimated as 6.3 at a distance of 0.284 nm, suggesting an arrangement similar to that in crystalline AgBr.
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Microsoft Windows uses the notion of registry to store all configuration information. The registry entries have associations and dependencies. For example, the paths to executables may be relative to some home directories. The registry being designed with faster access as one of the objectives does not explicitly capture these relations. In this paper, we explore a representation that captures the dependencies more explicitly using shared and unifying variables. This representation, called mRegistry exploits the tree-structured hierarchical nature of the registry, is concept-based and obtained in multiple stages. mRegistry captures intra-block, inter-block and ancestor-children dependencies (all leaf entries of a parent key in a registry put together as an entity constitute a block thereby making the block as the only child of the parent). In addition, it learns the generalized concepts of dependencies in the form of rules. We show that mRegistry has several applications: fault diagnosis, prediction, comparison, compression etc.