988 resultados para Plucker formula
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Introduction: Pre-implantation kidney biopsy is a decision-making tool when considering the use of grafts from deceased donors with expanded criteria, implanting one or two kidneys and comparing this to post-transplantation biopsies. The role of histopathological alterations in kidney compartments as a prognostic factor in graft survival and function has had conflicting results. Objective: This study evaluated the prevalence of chronic alterations in pre-implant biopsies of kidney grafts and the association of findings with graft function and survival in one year post-transplant. Methods: 110 biopsies were analyzed between 2006 and 2009 at Santa Casa de Porto Alegre, including live donors, ideal deceased donors and those with expanded criteria. The score was computed according to criteria suggested by Remuzzi. The glomerular filtration rate (GFR) was calculated using the abbreviated MDRD formula. Results: No statistical difference was found in the survival of donors stratified according to Remuzzi criteria. The GFR was significantly associated with the total scores in the groups with mild and moderate alterations, and in the kidney compartments alone, by univariate analysis. The multivariate model found an association with the presence of arteriosclerosis, glomerulosclerosis, acute rejection and delayed graft function. Conclusion: Pre-transplant chronic kidney alterations did not influence the post-transplantation one-year graft survival, but arteriosclerosis and glomerulosclerosis is predictive of a worse GFR. Delayed graft function and acute rejection are independent prognostic factors.
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The investments have always been considered as an essential backbone and so-called ‘locomotive’ for the competitive economies. However, in various countries, the state has been put under tight budget constraints for the investments in capital intensive projects. In response to this situation, the cooperation between public and private sector has grown based on public-private mechanism. The promotion of favorable arrangement for collaboration between public and private sectors for the provision of policies, services, and infrastructure in Russia can help to address the problems of dry ports development that neither municipalities nor the private sector can solve alone. Especially, the stimulation of public-private collaboration is significant under the exposure to externalities that affect the magnitude of the risks during all phases of project realization. In these circumstances, the risk in the projects also is becoming increasingly a part of joint research and risk management practice, which is viewed as a key approach, aiming to take active actions on existing global and specific factors of uncertainties. Meanwhile, a relatively little progress has been made on the inclusion of the resilience aspects into the planning process of a dry ports construction that would instruct the capacity planner, on how to mitigate the occurrence of disruptions that may lead to million dollars of losses due to the deviation of the future cash flows from the expected financial flows on the project. The current experience shows that the existing methodological base is developed fragmentary within separate steps of supply chain risk management (SCRM) processes: risk identification, risk evaluation, risk mitigation, risk monitoring and control phases. The lack of the systematic approach hinders the solution of the problem of risk management processes of dry port implementation. Therefore, management of various risks during the investments phases of dry port projects still presents a considerable challenge from the practical and theoretical points of view. In this regard, the given research became a logical continuation of fundamental research, existing in the financial models and theories (e.g., capital asset pricing model and real option theory), as well as provided a complementation for the portfolio theory. The goal of the current study is in the design of methods and models for the facilitation of dry port implementation through the mechanism of public-private partnership on the national market that implies the necessity to mitigate, first and foremost, the shortage of the investments and consequences of risks. The problem of the research was formulated on the ground of the identified contradictions. They rose as a continuation of the trade-off between the opportunities that the investors can gain from the development of terminal business in Russia (i.e. dry port implementation) and risks. As a rule, the higher the investment risk, the greater should be their expected return. However, investors have a different tolerance for the risks. That is why it would be advisable to find an optimum investment. In the given study, the optimum relates to the search for the efficient portfolio, which can provide satisfaction to the investor, depending on its degree of risk aversion. There are many theories and methods in finance, concerning investment choices. Nevertheless, the appropriateness and effectiveness of particular methods should be considered with the allowance of the specifics of the investment projects. For example, the investments in dry ports imply not only the lump sum of financial inflows, but also the long-term payback periods. As a result, capital intensity and longevity of their construction determine the necessity from investors to ensure the return on investment (profitability), along with the rapid return on investment (liquidity), without precluding the fact that the stochastic nature of the project environment is hardly described by the formula-based approach. The current theoretical base for the economic appraisals of the dry port projects more often perceives net present value (NPV) as a technique superior to other decision-making criteria. For example, the portfolio theory, which considers different risk preference of an investor and structures of utility, defines net present value as a better criterion of project appraisal than discounted payback period (DPP). Meanwhile, in business practice, the DPP is more popular. Knowing that the NPV is based on the assumptions of certainty of project life, it cannot be an accurate appraisal approach alone to determine whether or not the project should be accepted for the approval in the environment that is not without of uncertainties. In order to reflect the period or the project’s useful life that is exposed to risks due to changes in political, operational, and financial factors, the second capital budgeting criterion – discounted payback period is profoundly important, particularly for the Russian environment. Those statements represent contradictions that exist in the theory and practice of the applied science. Therefore, it would be desirable to relax the assumptions of portfolio theory and regard DPP as not fewer relevant appraisal approach for the assessment of the investment and risk measure. At the same time, the rationality of the use of both project performance criteria depends on the methods and models, with the help of which these appraisal approaches are calculated in feasibility studies. The deterministic methods cannot ensure the required precision of the results, while the stochastic models guarantee the sufficient level of the accuracy and reliability of the obtained results, providing that the risks are properly identified, evaluated, and mitigated. Otherwise, the project performance indicators may not be confirmed during the phase of project realization. For instance, the economic and political instability can result in the undoing of hard-earned gains, leading to the need for the attraction of the additional finances for the project. The sources of the alternative investments, as well as supportive mitigation strategies, can be studied during the initial phases of project development. During this period, the effectiveness of the investments undertakings can also be improved by the inclusion of the various investors, e.g. Russian Railways’ enterprises and other private companies in the dry port projects. However, the evaluation of the effectiveness of the participation of different investors in the project lack the methods and models that would permit doing the particular feasibility study, foreseeing the quantitative characteristics of risks and their mitigation strategies, which can meet the tolerance of the investors to the risks. For this reason, the research proposes a combination of Monte Carlo method, discounted cash flow technique, the theory of real options, and portfolio theory via a system dynamics simulation approach. The use of this methodology allows for comprehensive risk management process of dry port development to cover all aspects of risk identification, risk evaluation, risk mitigation, risk monitoring, and control phases. A designed system dynamics model can be recommended for the decision-makers on the dry port projects that are financed via a public-private partnership. It permits investors to make a decision appraisal based on random variables of net present value and discounted payback period, depending on different risks factors, e.g. revenue risks, land acquisition risks, traffic volume risks, construction hazards, and political risks. In this case, the statistical mean is used for the explication of the expected value of the DPP and NPV; the standard deviation is proposed as a characteristic of risks, while the elasticity coefficient is applied for rating of risks. Additionally, the risk of failure of project investments and guaranteed recoupment of capital investment can be considered with the help of the model. On the whole, the application of these modern methods of simulation creates preconditions for the controlling of the process of dry port development, i.e. making managerial changes and identifying the most stable parameters that contribute to the optimal alternative scenarios of the project realization in the uncertain environment. System dynamics model allows analyzing the interactions in the most complex mechanism of risk management process of the dry ports development and making proposals for the improvement of the effectiveness of the investments via an estimation of different risk management strategies. For the comparison and ranking of these alternatives in their order of preference to the investor, the proposed indicators of the efficiency of the investments, concerning the NPV, DPP, and coefficient of variation, can be used. Thus, rational investors, who averse to taking increased risks unless they are compensated by the commensurate increase in the expected utility of a risky prospect of dry port development, can be guided by the deduced marginal utility of investments. It is computed on the ground of the results from the system dynamics model. In conclusion, the outlined theoretical and practical implications for the management of risks, which are the key characteristics of public-private partnerships, can help analysts and planning managers in budget decision-making, substantially alleviating the effect from various risks and avoiding unnecessary cost overruns in dry port projects.
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A partir da denúncia da contraditória presença de pressupostos morais dogmáticos na formulação dos princípios norteadores da atividade científica, Nietzsche concebe uma outra noção de cientificidade, compatível com a opção hegemônica pelo saber, que ele reconhece como presente na cultura ocidental. O presente artigo visa a discutir sob quais parâmetros Nietzsche, no período intermediário de sua produção filosófica, empreende sua interpretação da cientificidade ocidental e como, apresentando-se como seu fomentador, ele formula uma crítica desmistificadora desta.
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The text examines Sergej Nikolajeviè Bulgakov's description of the philosopheme as thoroughly "immanent" (viz., the immanence of man qua being, such that ontology in Bulgakov becomes a conceptual analogue for immanence) and the corollary that such immanence necessarily excludes the problematic of the "creation of the world." Because of this resolute immanence and the notion that the creation of the world in the form of creatio ex nihilo requires a non-immanent or non-ontological thought and concept, the problematic for Bulgakov is approached only by a theologeme. Appropriating this argument as material for a cursory philosopheme, the text attempts to transform Bulgakov's theologeme into a philosopheme through an elision of God and dogma that overdetermines the theologeme. This philosopheme (nascent within Bulgakov's work itself, in both his hesitation to the overdetermination of immanence and the commitment to the problem of creation) would be a thoroughly non-ontological philosopheme, one that allows for the treatment of the problematic of "creation" or singular ontogenesis, yet with the corollary that this philosopheme must rely on an "ontological zero" Such a philosopheme qua ontologically empty formula nevertheless remains ontologically significant insofar as it is to evince the limit of ontology, in the ontological zero's non-relationality to ontology.
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This thesis work studies the modelling of the colour difference using artificial neural network. Multilayer percepton (MLP) network is proposed to model CIEDE2000 colour difference formula. MLP is applied to classify colour points in CIE xy chromaticity diagram. In this context, the evaluation was performed using Munsell colour data and MacAdam colour discrimination ellipses. Moreover, in CIE xy chromaticity diagram just noticeable differences (JND) of MacAdam ellipses centres are computed by CIEDE2000, to compare JND of CIEDE2000 and MacAdam ellipses. CIEDE2000 changes the orientation of blue areas in CIE xy chromaticity diagram toward neutral areas, but on the whole it does not totally agree with the MacAdam ellipses. The proposed MLP for both modelling CIEDE2000 and classifying colour points showed good accuracy and achieved acceptable results.
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Contient : Pièces concernant la Suisse et les relations diplomatiques de ce pays avec la France, 1574-1602 ; Traité de Monçon, 1626 ; État des revenus du roi d'Espagne, 1610 (f. 36), — et de ses dépenses (f. 46) ; État des revenus du roi de Portugal, 1610 (f. 53), — et de ses dépenses (f. 54 v) ; Mémoires sur la cour de Rome, au temps de Paul V ; Traité entre la France et les Pays-Bas, 1634 ; Pièces concernant les protestants de Béarn, 1620 ; Harangue de Villeroy aux États de la Ligue, 1593 ; « Extraict de quelques passages du livre intitulé L'homme d'Estat français vrayement catholicque, dédié au roy très-chrestien Louys-le-Juste, par le sieur de Chiremont » [Le Normant], 1626 ; Entrée de Louis XIII à La Rochelle, 1628 ; « Discours... fais par feu monsieur BACON, grand chancelier d'Angleterre » : « De la religion » et « De la superstition » ; Traité entre la Lorraine et la France, 1634 ; Traité avec les archiducs Albert et Isabelle, 1610 ; Traité de Prague entre l'Empire et la Saxe, 1635 ; « Harangue de monsieur d'Avaux aux États de Suède, assemblés à Stocholme » ; « Formula Stumsdorfianorum pactorum de induciis XXVI annorum inter... Poloniæ regem, magnumque ducem Lithuaniæ, etc., etc., regnum Poloniæ magnumque ducatum Lithuaniæ, ab una, et... reginam regnumque Sueciæ, etc., ab altera parte sancitis, XXIV articulis comprehensa », 1635 ; « Discours sur les moiens que tiennent les Espagnols pour parvenir à la monarchie de l'Europe, et ce que l'on peut faire pour les en empescher » ; « Conférence secrette de Henri-le-Grand, tenüe pour le sujet des moiens de parvenir à l'Empire... » ; « Sommaire déclaration des aydes et charges que les roys de France ont levées en leur royaume, et des inconvéniens et troubles advenus par aucunes violences et non accoustumées exactions, par VIGNER » [Nicolas VIGNIER, médecin] ; « Harangue faite au Roy, séant en son Parlement, par monsieur Bignon, son advocat-général », 1636 ; Mémoires sur la validité ou nullité du mariage de Gaston d'Orléans avec Marguerite de Lorraine, en latin
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Contient : 1 Notes concernant Toulouse et autres villes : « De fundacione urbis Tholose... De aliarum urbium antiquarum fundacione... ». En latin et en français ; 2 « Description faicte par manière de repertoire des procès, documens, escriptures, vidimus, lectres, privilièges et autres choses estans de present dans les archieux de la maison commune de Thoulouse, et ce par honnorable homme messire Bernard de Gailhac, licencié ez loix, assesseur de nobles seignieurs les capitolz de la ville et cité de Tholose et commis par eulx à ce faire una mecum Maturino Foresterii, notaire ordinaire de la court desd. capitols et escrivain du present repertoire, par lesd. seignieurs à ce depputé, faict et commancé le XXIIe jour du moys de janvier, l'an mil quatre cens quatrevingtz et quatorze... Et premièrement au premier armaire des susd. archieux, signé devant par lectre A, trouvarez tout ce que s'ensuyt... » ; 3 « S'ensuit une autre description et repertoire des privileges, arrestz, instrumens, documens, et de toutes les autres lettres estans au livre blanc de la Maison commune de Tholose, par manière de recolection des matières qui sont dedans led. Livre Blanc, et coadunation d'icelles, ainsi comme il peult apparoir cy après... » ; 4 « Arrestum super forma electionis capitulariorum Tholose ». En français ; 5 « Ordo doctorum Academiae Tolosanae decrevit proxime, quod nos proscribere jussi sumus ut omnes studiosi adolescentes quicumque ipsis doctoribus operam dare volent publice profiteantur qui sint et unde domo... Datum kalendis januariis, anno 1582. FRANCISCUS ROALDUS, rector ». En latin. Pièce imprimée, au dos de laquelle sont écrits : « Capita jurisjurandi ex formula praescripta iis qui in matriculatis haberi volunt, et in tabulas publicas Academiae Tolosanae referri » ; 6 « Extraict des regestres de parlement » de Toulouse, concernant les « docteurs regens èz » Universités situées dans le ressort dudit parlement et les écoliers de l'Université de Toulouse. 18 août 1582. « Ainsi signé : Du Tornoer ». Pièce imprimée
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Contient : 1 Instruction du roi « CHARLES » IX au « Sr de L'Isle », envoyé en mission pour l'élection du roi de Pologne. « Faict à Paris, le XIIIIe octobre 1573 » ; 2 Lettre du roi « CHARLES [IX]... à mon cousin le duc de Nyvernois, gouverneur... delà les montz... Escript au chasteau de Vincennes, le XIIIIe jour de mars 1574 » ; 3 Lettre du roi « CHARLES [IX]... à mon cousin le duc de Nyvernois, gouverneur... delà les montz... Escript au bois de Vincennes, le XIIIIe jour de mars 1574 » ; 4 Mémorial de pièces relatives à l'élection de Henri, duc d'Anjou, comme roi de Pologne, en 1573, telles que instructions, pouvoirs, harangues, traités, etc. Copies ; 5 « Memoires du Sr DE LANSSAC,... au roy de Pologne... Blamont, 1573 » ; 6 « Copie de la response du roy de Pollongne au roy de Suede... Escript à Villiers Costeretz, le XVIe jour d'octobre 1573 » ; 7 Formule du serment de Henri, duc d'Anjou, comme roi de Pologne. En latin ; 8 « Discours sur le gouvernement des affaires particulieres » ; 9 « Ordo qualiter serenissimus rex Poloniae... coronari debeat, et quae solennitas et ceremoniae circa id servari sint solitae ». En latin ; 10 « Version des affaires passées devant le couronnement du roy », renfermant l'« advertissement faict au roy devant le serment... [et le] serment presté par le... roy de Pollogne », etc. Copie ; 11 « Sommaire de la declaration du roy sur le depart des comices de son couronnement ». Copie ; 12 « Extraict de la protestation faicte par l'archevesque de Gnesne... le 16 may 1573 » ; 13 « Formula... de coronatione regis Poloniae ». Copie. En latin ; 14 « Testamentum SIGISMUNDI AUGUSTI, regis Poloniae, etc., ex polonico in latinum translatum ». Copie. En latin ; 15 Serments de fidélité de quatre villes de Pologne au roi Casimir IV, 1454. Copies. En latin ; 16 « Recessus comiciorum corronationis regis Henrici Poloniae... Datum Cracoviae, 22 aprilis... 1574 ». En latin ; 17 Sommaire « de plusieurs lettres de grands seigneurs envoyées aux Estatz de Pologne pendant l'interregne » ; 18 « Admonitio [ad regem] ante juramentum ». En latin ; 19 Copie du diplôme des sénateurs et des divers ordres du royaume de Pologne, portant confirmation par Henri, roi de Pologne, des droits et priviléges du royaume, dans les comices généraux de l'élection, près de Varsovie, à Kannjen, le 20 mai 1573. En latin ; 20 « Articuli de reformatione ». En latin ; 21 « Extraits de plusieurs lettres des princes et du pape aux Etats de Pologne, pendant l'interregne ; avec les reponses des Etats. 1573 ». En latin
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Servicios registrales
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Introduction In Difference and Repetition, Deleuze compares and contrasts Kierkegaard's and Nietzsche's ideas of repetition. He argues that neither of them really give a representation of repetition. Repetition for them is a sort of selective task: the way in which they determine what is ethical and eternal. With Nietzsche, it is a theater of un belie f. ..... Nietzsche's leading idea is to found the repetition in the etemal return at once on the death of God and the dissolution of the self But it is a quite different alliance in the theater of faith: Kierkegaard dreams of alliance between a God and a self rediscovered. I Repetition plays a theatrical role in their thinking. It allows them to dramatically stage the interplay of various personnae. Deleuze does give a positive account ofKierkegaard's "repetition"; however, he does not think that Kierkegaard works out a philosophical model, or a representation of what repetition is. It is true that in the book Repetition, Constantin Constantius does not clearly and fully work out the concept of repetition, but in Sickness Unto Death, Kierkegaard gives a full explanation of the self and its temporality which can be connected with repetition. When Sickness Unto Death is interpreted according to key passages from Repetition and The Concept of Anxiety, a clear philosophical concept of repetition can be established. In my opinion, Kierkegaard's philosophy is about the task of becoming a self, and I will be attempting to show that he does have a model of the temporality of self-becoming. In Sickness Unto Death, Kierkegaard explains his notions of despair with reference to sin, self, self-becoming, faith, and repetition. Despair is a sickness of the spirit, of the self, and accordingly can take three forms: in despair not to be conscious of having a self (not despair in the strict sense); in despair not to will to be oneself; in despair to will to be oneself2 In relation to this definition, he defines a self as "a relation that relates itself to itself and in relating itself to itself relates to another.''3 Thus, a person is a threefold relationship, and any break in that relationship is despair. Despair takes three forms corresponding to the three aspects of a self s relation to itself Kierkegaard says that a selfis like a house with a basement, a first floor, and a second floor.4 This model of the house, and the concept of the stages on life's way that it illustrates, is central to Kierkegaard's philosophy. This thesis will show how he unpacks this model in many of his writings with different concepts being developed in different texts. His method is to work with the same model in different ways throughout his authorship. He assigns many of the texts to different pseudonyms, but in this thesis we will treat the model and the related concepts as being Kierkegaard's and not only the pseudonyms. This is justified as our thesis will show this modelremains the same throughout Kierkegaard's work, though it is treated in different ways by different pseudonyms. According to Kierkegaard, many people live in only the basement for their entire lives, that is, as aesthetes ("in despair not to be conscious of having a self'). They live in despair of not being conscious of having a self They live in a merely horizontal relation. They want to get what they desire. When they go to the first floor, so to speak, they reflect on themselves and only then do they begin to get a self In this stage, one acquires an ideology of the required and overcomes the strict commands of the desired. The ethical is primarily an obedience to the required whereas the aesthetic is an obedience to desire. In his work Fear and Trembling (Copenhagen: 1843), Johannes de Silentio makes several observations concerning this point. In this book, the author several times allows the desired ideality of esthetics to be shipwrecked on the required ideality of ethics, in order through these collisions to bring to light the religious ideality as the ideality that precisely is the ideality of actuality, and therefore just as desirable as that of esthetics and not as impossible as the ideality of ethics. This is accomplished in such a way that the religious ideality breaks forth in the dialectical leap and in the positive mood - "Behold all things have become new" as well as in the negative mood that is the passion of the absurd to which the concept "repetition" corresponds.s Here one begins to become responsible because one seeks the required ideality; however, the required ideality and the desired ideality become inadequate to the ethical individual. Neither of them satisfy him ("in despair not to will to be oneself'). Then he moves up to the second floor: that is, the mystical region, or the sphere of religiousness (A) ("despair to will to be oneself). Kiericegaard's model of a house, which is connected with the above definition ofdespair, shows us how the self arises through these various stages, and shows the stages of despair as well. On the second floor, we become mystics, or Knights of Infinite Resignation. We are still in despair because we despair ofthe basement and the first floor, however, we can be fiill, free persons only ifwe live on all the floors at the same time. This is a sort of paradoxical fourth stage consisting of all three floors; this is the sphere of true religiousness (religiousness (B)). It is distinguished from religiousness (A) because we can go back and live on all the floors. It is not that there are four floors, but in the fourth stage, we live paradoxically on three at once. Kierkegaard uses this house analogy in order to explain how we become a self through these stages, and to show the various stages of despair. Consequently, I will be explaining self-becoming in relation to despair. It will also be necessary to explain it in relation to faith, for faith is precisely the overcoming of despair. After explaining the becoming of the self in relation to despair and faith, I will then explain its temporality and thereby its repetition. What Kierkegaard calls a formula, Deleuze calls a representation. Unfortunately, Deleuze does not acknowledge Kierkegaard's formula for repetition. As we shall see, Kierkegaard clearly gives a formula for despair, faith, and selfbecoming. When viewed properly, these formulae yield a formula for repetition because when one hasfaith, the basement, firstfloor, and secondfloor become new as one becomes oneself The self is not bound in the eternity ofthe first floor (ethical) or the temporality of the basement (aesthete). I shall now examine the two forms of conscious despair in such a way as to point out also a rise in the consciousness of the nature of despair and in the consciousness that one's state is despair, or, what amounts to the same thing and is the salient point, a rise in the consciousness of the self The opposite to being in despair is to have faith. Therefore, the formula set forth above, which describes a state in which there is not despair at all, is entirely correct, and this formula is also the formula for faMi in ^elating itself to itself and in willing to be itself, the self rests transparently in the power that established it.
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Two new families of building blocks have been prepared and fully characterized and their coordination chemistry exploited for the preparation of molecule-based magnetic materials. The first class of compounds were prepared by exploiting the chemistry of 3,3'-diamino-2,2'-bipyridine together with 2-pyridine carbonyl chloride or 2-pyridine aldehyde. Two new ligands, 2,2'-bipyridine-3,3'-[2-pyridinecarboxamide] (Li, 2.3) and N'-6/s(2-pyridylmethyl) [2,2'bipyridine]-3,3'-diimine (L2, 2.7), were prepared and characterized. For ligand L4, two copper(II) coordination compounds were isolated with stoichiometrics [Cu2(Li)(hfac)2] (2.4) and [Cu(Li)Cl2] (2.5). The molecular structures of both complexes were determined by X-ray crystallography. In both complexes the ligand is in the dianionic form and coordinates the divalent Cu(II) ions via one amido and two pyridine nitrogen donor atoms. In (2.4), the coordination geometry around both Cu11 ions is best described as distorted trigonal bipyramidal where the remaining two coordination sites are satisfied by hfac counterions. In (2.5), both Cu(II) ions adopt a (4+1) distorted square pyramidal geometry. One copper forms a longer apical bond to an adjacent carbonyl oxygen atom, whereas the second copper is chelated to a neighboring Cu-Cl chloride ion to afford chloride bridged linear [Cu2(Li)Cl2]2 tetramers that run along the c-axis of the unit cell. The magnetic susceptibility data for (2.4) reveal the occurrence of weak antiferromagnetic interactions between the copper(II) ions. In contrast, variable temperature magnetic susceptibility measurements for (2.5) reveal more complex magnetic properties with the presence of ferromagnetic exchange between the central dimeric pair of copper atoms and weak antiferromagnetic exchange between the outer pairs of copper atoms. The Schiff-base bis-imine ligand (L2, 2.7) was found to be highly reactive; single crystals grown from dry methanol afforded compound (2.14) for which two methanol molecules had added across the imine double bond. The susceptibility of this ligand to nucleophilic attack at its imine functionality assisted via chelation to Lewis acidic metal ions adds an interesting dimension to its coordination chemistry. In this respect, a Co(II) quaterpyridine-type complex was prepared via a one-pot transformation of ligand L2 in the presence of a Lewis acidic metal salt. The rearranged complex was characterized by X-ray crystallography and a reaction mechanism for its formation has been proposed. Three additional rearranged complexes (2.13), (2.17) and (2.19) were also isolated when ligand (L2, 2.7) was reacted with transition metal ions. The molecular structures of all three complexes have been determined by X-ray crystallography. The second class of compounds that are reported in this thesis, are the two diacetyl pyridine derivatives, 4-pyridyl-2,6-diacetylpyridine (5.5) and 2,2'-6,6'-tetraacetyl-4,4'-bipyridine (5.15). Both of these compounds have been designed as intermediates for the metal templated assembly of a Schiff-base N3O2 macrocycle. From compound (5.15), a covalently tethered dimeric Mn(II) macrocyclic compound of general formula {[Mn^C^XJCl-FkO^Cl-lO.SFbO (5.16) was prepared and characterized. The X-ray analysis of (5.16) reveals that the two manganese ions assume a pentagonal-bipyramidal geometry with the macrocycle occupying the pentagonal plane and the axial positions being filled by a halide ion and a H2O molecule. Magnetic susceptibility data reveal the occurrence of antiferromagnetic interactions between covalently tethered Mn(II)-Mn(II) dimeric units. Following this methodology a Co(II) analogue (5.17) has also been prepared which is isostructural with (5.16).
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Exch~nge energy of the He-He system is calculated using the one-density matrix which has been modified according to the supermolecular density formula quoted by Kolos. The exchange energy integrals are computed analytically and by the Monte Carlo method. The results obtained from both ways compared favourably,with the results obtained from the SCF program HONDO
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The one-electron reduced local energy function, t ~ , is introduced and has the property < tL)=(~>. It is suggested that the accuracy of SL reflects the local accuracy of an approximate wavefunction. We establish that <~~>~ <~2,> and present a bound formula, E~ , which is such that where Ew is Weinstein's lower bound formula to the ground state. The nature of the bound is not guaranteed but for sufficiently accurate wavefunctions it will yield a lower bound. ,-+ 1'S I I Applications to X LW Hz. and ne are presented.
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A study was devised to evaluate influences of irrigation and fertigation practices on Vitis vinifera and Vitis labruscana grapes in the Niagara Peninsula. A modified FAO Penman- Monteith evapotranspiration formula was used to calculate water budgets and schedule irrigations. Five deficit irrigation treatments (non-irrigated control; deficits imposed postbloom, lag phase, and veraison; fiiU season irrigation) were employed in a Chardonnay vineyard. Transpiration rate (4-7 /xg H20/cmVs) and soil moisture data demonstrated that the control and early deficit treatments were under water stress throughout the season. The fiiU season irrigation treatment showed an 18% (2001) and 19% (2002) increase in yield over control due to increased berry weight. Soluble solids and wine quality were not compromised, and the fiiU season treatment showed similar or higher °Brix than all other treatments. Berry titratable acidity andpH also fell within acceptable levels for all five treatments. Irrigation/fertigation timing trials were conducted on Concord and Niagara vines in 2001- 02. The six Concord treatments consisted of a non-irrigated control, irrigation fi^om Eichhom and Lorenz (EL) stage 12 to harvest, and four fertigation treatments which applied 70 kg/ha urea. The nine Niagara treatments included a non-irrigated control, two irrigated treatments (ceasing at veraison and harvest, respectively) and six fertigation treatments of various durations. Slight yield increases (ca. 10% in Concord; 29% in Niagara) were accompanied by small decreases in soluble solids (1.5°Brix), and methyl anthranilate concentrations. Transpiration rate and soil moisture (1 1.9-16.3%) data suggested that severe water stress was present in these Toledo clay based vineyards.
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We prepared samples of MgB2 and ran sets of experiments aimed for investigation of superconducting properties under pressure. We found the value of pressure derivative of the transition temperature -1.2 ± 0.05 K/GPa. Then, using McMillan formula, we found that the main contribution to the change of the transition temperature under the pressure is due to the change in phonon frequencies. Griineisen parameter was calculated to be 7g = 2.4. Our results suggest that MgB2 is a conventional superconductor.