919 resultados para Auto-analyzer, Technicon according to US EPA (1979)


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This work deals with the stages of the process of renewal of a Notice of Inspection of Fire Department (AVCB) set of structural measures, technical and organizational integrated to ensure the building an optimum level of protection in the security segment fire and panic according to the laws of fire safety standards. The work presented all the literature about the process, their justifications to force deploy in a company to fire safety, the benefits that this standard offers, the facilities in a company that has a AVCB and the great importance in society, presents some examples where there contained the fire safety regulations and their unhappy outcomes, difficulties encountered, examples of how to proceed, step by step and the lesson that this process requires great care, dedication, professionals with the required knowledge and severity to completion

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The numbers of fires detected on forest, savanna and transition lands during the 2002-10 biomass burning seasons in Amazonia are shown using fire count data and co-located land cover classifications from the Moderate Resolution Imaging Spectroradiometer (MODIS). The ratio of forest fires to savanna fires has varied substantially over the study period, with a maximum ratio of 0.65:1 in 2005 and a minimum ratio of 0.27:1 in 2009, with the four lowest years occurring in 2007-10. The burning during the droughts of 2007 and 2010 is attributed to a higher number of savanna fires relative to the drought of 2005. A decrease in the regional mean single scattering albedo of biomass burning aerosols, consistent with the shift from forest to savanna burning, is also shown. During the severe drought of 2010, forest fire detections were lower in many areas compared with 2005, even though the drought was more severe in 2010. This result suggests that improved fire management practices, including stricter burning regulations as well as lower deforestation burning, may have reduced forest fires in 2010 relative to 2005 in some areas of the Amazon Basin.

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«In altri termini mi sfuggiva e ancora oggi mi sfugge gran parte del significato dell’evoluzione del tempo; come se il tempo fosse una materia che osservo dall’esterno. Questa mancanza di evoluzione è fonte di alcune mie sventure ma anche mi appartiene con gioia.» Aldo Rossi, Autobiografia scientifica. The temporal dimension underpinning the draft of Autobiografia scientifica by Aldo Rossi may be referred to what Lucien Lévy-Bruhl, the well-known French anthropologist, defines as “primitive mentality” and “prelogical” conscience : the book of life has lost its page numbers, even punctuation. For Lévy-Bruhl, but certainly for Rossi, life or its summing up becomes a continuous account of ellipses, gaps, repetitions that may be read from left to right or viceversa, from head to foot or viceversa without distinction. Rossi’s autobiographical writing seems to accept and support the confusion with which memories have been collected, recording them after the order memory gives them in the mental distillation or simply according to the chronological order in which they have happened. For Rossi, the confusion reflects the melting of memory elements into a composite image which is the result of a fusion. He is aware that the same sap pervades all memories he is going to put in order: each of them has got a common denominator. Differences have diminished, almost faded; the quick glance is prevalent over the distinction of each episode. Rossi’s writing is beyond the categories dependent on time: past and present, before and now. For Rossi, the only repetition – the repetition the text will make possible for an indefinite number of times – gives peculiarity to the event. As Gilles Deleuze knows, “things” may only last as “singleness”: more frequent the repetition is, more singular is the memory phenomenon that recurs, because only what is singular magnifies itself and happens endlessly forever. Rossi understands that “to raise the first time to nth forever”, repetition becomes glorification . It may be an autobiography that, celebrating the originality, enhances the memory event in the repetition; in fact it greatly differs from the biographical reproduction, in which each repetition is but a weaker echo, a duller copy, provided with a smaller an smaller power in comparison with the original. Paradoxically, for Deleuze the repetition asserts the originality and singularity of what is repeated. Rossi seems to share the thought expressed by Kierkegaard in the essay Repetition: «The hope is a graceful maiden slipping through your fingers; the memory of an elderly woman, indeed pretty, but never satisfactory if necessary; the repetition is a loved friend you are never tired of, as it is only the new to make you bored. The old never bores you and its presence makes you happy [...] life is but a repetition [...] here is the beauty of life» . Rossi knows well that repetition hints at the lasting stability of cosmic time. Kierkegaard goes on: «The world exists, and it exists as a repetition» . Rossi devotes himself, on purpose and in all conscience, to collect, to inventory and «to review life», his own life, according to a recovery not from the past but of the past: a search work, the «recherche du temps perdu», as Proust entitled his masterpiece on memory. If you want the past time to be not wasted, you must give it presence. «Memoria e specifico come caratteristiche per riconoscere se stesso e ciò che è estraneo mi sembravano le più chiare condizioni e spiegazioni della realtà. Non esiste uno specifico senza memoria, e una memoria che non provenga da un momento specifico; e solo questa unione permette la conoscenza della propria individualità e del contrario (self e non-self)» . Rossi wants to understand himself, his own character; it is really his own character that requires to be understood, to increase its own introspective ability and intelligence. «Può sembrare strano che Planck e Dante associno la loro ricerca scientifica e autobiografica con la morte; una morte che è in qualche modo continuazione di energia. In realtà, in ogni artista o tecnico, il principio della continuazione dell’energia si mescola con la ricerca della felicità e della morte» . The eschatological incipit of Rossi’s autobiography refers to Freud’s thought in the exact circularity of Dante’s framework and in as much exact circularity of the statement of the principle of the conservation of energy: in fact it was Freud to connect repetition to death. For Freud, the desire of repetition is an instinct rooted in biology. The primary aim of such an instinct would be to restore a previous condition, so that the repeated history represents a part of the past (even if concealed) and, relieving the removal, reduces anguish and tension. So, Freud ask himself, what is the most remote state to which the instinct, through the repetition, wants to go back? It is a pre-vital condition, inorganic of the pure entropy, a not-to-be condition in which doesn’t exist any tension; in other words, Death. Rossi, with the theme of death, introduces the theme of circularity which further on refers to the sense of continuity in transformation or, in the opposite way, the transformation in continuity. «[...] la descrizione e il rilievo delle forme antiche permettevano una continuità altrimenti irripetibile, permettevano anche una trasformazione, una volta che la vita fosse fermata in forme precise» . Rossi’s attitude seems to hint at the reflection on time and – in a broad sense – at the thought on life and things expressed by T.S. Eliot in Four Quartets: «Time present and time past / Are both perhaps present in time future, / And time future is contained in time past. / I all time is eternally present / All time is unredeemable. / What might have been is an abstraction / Remaining perpetual possibility / Only in a word of speculation. / What might have been and what has been / Point to one end, which is always present. [...]» . Aldo Rossi’s autobiographical story coincides with the description of “things” and the description of himself through the things in the exact parallel with craft or art. He seems to get all things made by man to coincide with the personal or artistic story, with the consequent immediate necessity of formulating a new interpretation: the flow of things has never met a total stop; all that exists nowadays is but a repetition or a variant of something existing some time ago and so on, without any interruption until the early dawnings of human life. Nevertheless, Rossi must operate specific subdivisions inside the continuous connection in time – of his time – even if limited by a present beginning and end of his own existence. This artist, as an “historian” of himself and his own life – as an auto-biographer – enjoys the privilege to be able to decide if and how to operate the cutting in a certain point rather than in another one, without being compelled to justify his choice. In this sense, his story is a matter very ductile and flexible: a good story-teller can choose any moment to start a certain sequence of events. Yet, Rossi is aware that, beyond the mere narration, there is the problem to identify in history - his own personal story – those flakings where a clean cut enables the separation of events of different nature. In order to do it, he has to make not only an inventory of his own “things”, but also to appeal to authority of the Divina Commedia started by Dante when he was 30. «A trent’anni si deve compiere o iniziare qualcosa di definitivo e fare i conti con la propria formazione» . For Rossi, the poet performs his authority not only in the text, but also in his will of setting out on a mystical journey and handing it down through an exact descriptive will. Rossi turns not only to the authority of poetry, but also evokes the authority of science with Max Plank and his Scientific Autobiography, published, in Italian translation, by Einaudi, 1956. Concerning Planck, Rossi resumes an element seemingly secondary in hit account where the German physicist «[...] risale alle scoperte della fisica moderna ritrovando l’impressione che gli fece l’enunciazione del principio di conservazione dell’energia; [...]» . It is again the act of describing that links Rossi to Planck, it is the description of a circularity, the one of conservation of energy, which endorses Rossi’s autobiographical speech looking for both happiness and death. Rossi seems to agree perfectly to the thought of Planck at the opening of his own autobiography: «The decision to devote myself to science was a direct consequence of a discovery which was never ceased to arouse my enthusiasm since my early youth: the laws of human thought coincide with the ones governing the sequences of the impressions we receive from the world surrounding us, so that the mere logic can enable us to penetrate into the latter one’s mechanism. It is essential that the outer world is something independent of man, something absolute. The search of the laws dealing with this absolute seems to me the highest scientific aim in life» . For Rossi the survey of his own life represents a way to change the events into experiences, to concentrate the emotion and group them in meaningful plots: «It seems, as one becomes older. / That the past has another pattern, and ceases to be a mere sequence [...]» Eliot wrote in Four Quartet, which are a meditation on time, old age and memory . And he goes on: «We had the experience but missed the meaning, / And approach to the meaning restores the experience / In a different form, beyond any meaning [...]» . Rossi restores in his autobiography – but not only in it – the most ancient sense of memory, aware that for at least 15 centuries the Latin word memoria was used to show the activity of bringing back images to mind: the psychology of memory, which starts with Aristotele (De Anima), used to consider such a faculty totally essential to mind. Keith Basso writes: «The thought materializes in the form of “images”» . Rossi knows well – as Aristotele said – that if you do not have a collection of mental images to remember – imagination – there is no thought at all. According to this psychological tradition, what today we conventionally call “memory” is but a way of imagining created by time. Rossi, entering consciously this stream of thought, passing through the Renaissance ars memoriae to reach us gives a great importance to the word and assumes it as a real place, much more than a recollection, even more than a production and an emotional elaboration of images.

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This thesis presents a creative and practical approach to dealing with the problem of selection bias. Selection bias may be the most important vexing problem in program evaluation or in any line of research that attempts to assert causality. Some of the greatest minds in economics and statistics have scrutinized the problem of selection bias, with the resulting approaches – Rubin’s Potential Outcome Approach(Rosenbaum and Rubin,1983; Rubin, 1991,2001,2004) or Heckman’s Selection model (Heckman, 1979) – being widely accepted and used as the best fixes. These solutions to the bias that arises in particular from self selection are imperfect, and many researchers, when feasible, reserve their strongest causal inference for data from experimental rather than observational studies. The innovative aspect of this thesis is to propose a data transformation that allows measuring and testing in an automatic and multivariate way the presence of selection bias. The approach involves the construction of a multi-dimensional conditional space of the X matrix in which the bias associated with the treatment assignment has been eliminated. Specifically, we propose the use of a partial dependence analysis of the X-space as a tool for investigating the dependence relationship between a set of observable pre-treatment categorical covariates X and a treatment indicator variable T, in order to obtain a measure of bias according to their dependence structure. The measure of selection bias is then expressed in terms of inertia due to the dependence between X and T that has been eliminated. Given the measure of selection bias, we propose a multivariate test of imbalance in order to check if the detected bias is significant, by using the asymptotical distribution of inertia due to T (Estadella et al. 2005) , and by preserving the multivariate nature of data. Further, we propose the use of a clustering procedure as a tool to find groups of comparable units on which estimate local causal effects, and the use of the multivariate test of imbalance as a stopping rule in choosing the best cluster solution set. The method is non parametric, it does not call for modeling the data, based on some underlying theory or assumption about the selection process, but instead it calls for using the existing variability within the data and letting the data to speak. The idea of proposing this multivariate approach to measure selection bias and test balance comes from the consideration that in applied research all aspects of multivariate balance, not represented in the univariate variable- by-variable summaries, are ignored. The first part contains an introduction to evaluation methods as part of public and private decision process and a review of the literature of evaluation methods. The attention is focused on Rubin Potential Outcome Approach, matching methods, and briefly on Heckman’s Selection Model. The second part focuses on some resulting limitations of conventional methods, with particular attention to the problem of how testing in the correct way balancing. The third part contains the original contribution proposed , a simulation study that allows to check the performance of the method for a given dependence setting and an application to a real data set. Finally, we discuss, conclude and explain our future perspectives.

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The MTDL (multi-target-directed ligand) design strategy is used to develop single chemical entities that are able to simultaneously modulate multiple targets. The development of such compounds might disclose new avenues for the treatment of a variety of pathologies (e.g. cancer, AIDS, neurodegenerative diseases), for which an effective cure is urgently needed. This strategy has been successfully applied to Alzheimer’s disease (AD) due to its multifactorial nature, involving cholinergic dysfunction, amyloid aggregation, and oxidative stress. Despite many biological entities have been recognized as possible AD-relevant, only four achetylcholinesterase inhibitors (AChEIs) and one NMDA receptor antagonist are used in therapy. Unfortunately, such compounds are not disease-modifying agents behaving only as cognition enhancers. Therefore, MTDL strategy is emerging as a powerful drug design paradigm: pharmacophores of different drugs are combined in the same structure to afford hybrid molecules. In principle, each pharmacophore of these new drugs should retain the ability to interact with its specific site(s) on the target and, consequently, to produce specific pharmacological responses that, taken together, should slow or block the neurodegenerative process. To this end, the design and synthesis of several examples of MTDLs for combating neurodegenerative diseases have been published. This seems to be the more appropriate approach for addressing the complexity of AD and may provide new drugs for tackling the multifactorial nature of AD, and hopefully stopping its progression. According to this emerging strategy, in this work thesis different classes of new molecular structures, based on the MTDL approach, have been developed. Moreover, curcumin and its constrained analogs have currently received remarkable interest as they have a unique conjugated structure which shows a pleiotropic profile that we considered a suitable framework in developing MTDLs. In fact, beside the well-known direct antioxidant activity, curcumin displays a wide range of biological properties including anti-inflammatory and anti-amyloidogenic activities and an indirect antioxidant action through activation of the cytoprotective enzyme heme oxygenase (HO-1). Thus, since many lines of evidence suggest that oxidative stess and mitochondria impairment have a cental role in age-related neurodegenerative diseases such as AD, we designed mitochondria-targeted antioxidants by connecting curcumin analogs to different polyamine chains that, with the aid of electrostatic force, might drive the selected antioxidant moiety into mitochondria.

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In this treatise we consider finite systems of branching particles where the particles move independently of each other according to d-dimensional diffusions. Particles are killed at a position dependent rate, leaving at their death position a random number of descendants according to a position dependent reproduction law. In addition particles immigrate at constant rate (one immigrant per immigration time). A process with above properties is called a branching diffusion withimmigration (BDI). In the first part we present the model in detail and discuss the properties of the BDI under our basic assumptions. In the second part we consider the problem of reconstruction of the trajectory of a BDI from discrete observations. We observe positions of the particles at discrete times; in particular we assume that we have no information about the pedigree of the particles. A natural question arises if we want to apply statistical procedures on the discrete observations: How can we find couples of particle positions which belong to the same particle? We give an easy to implement 'reconstruction scheme' which allows us to redraw or 'reconstruct' parts of the trajectory of the BDI with high accuracy. Moreover asymptotically the whole path can be reconstructed. Further we present simulations which show that our partial reconstruction rule is tractable in practice. In the third part we study how the partial reconstruction rule fits into statistical applications. As an extensive example we present a nonparametric estimator for the diffusion coefficient of a BDI where the particles move according to one-dimensional diffusions. This estimator is based on the Nadaraya-Watson estimator for the diffusion coefficient of one-dimensional diffusions and it uses the partial reconstruction rule developed in the second part above. We are able to prove a rate of convergence of this estimator and finally we present simulations which show that the estimator works well even if we leave our set of assumptions.

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Millisecond Pulsars (MSPs) are fast rotating, highly magnetized neutron stars. According to the "canonical recycling scenario", MSPs form in binary systems containing a neutron star which is spun up through mass accretion from the evolving companion. Therefore, the final stage consists of a binary made of a MSP and the core of the deeply peeled companion. In the last years, however an increasing number of systems deviating from these expectations has been discovered, thus strongly indicating that our understanding of MSPs is far to be complete. The identification of the optical companions to binary MSPs is crucial to constrain the formation and evolution of these objects. In dense environments such as Globular Clusters (GCs), it also allows us to get insights on the cluster internal dynamics. By using deep photometric data, acquired both from space and ground-based telescopes, we identified 5 new companions to MSPs. Three of them being located in GCs and two in the Galactic Field. The three new identifications in GCs increased by 50% the number of such objects known before this Thesis. They all are non-degenerate stars, at odds with the expectations of the "canonical recycling scenario". These results therefore suggest either that transitory phases should also be taken into account, or that dynamical processes, as exchange interactions, play a crucial role in the evolution of MSPs. We also performed a spectroscopic follow-up of the companion to PSRJ1740-5340A in the GC NGC 6397, confirming that it is a deeply peeled star descending from a ~0.8Msun progenitor. This nicely confirms the theoretical expectations about the formation and evolution of MSPs.

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International migration has increased rapidly in the Czech Republic, with more than 150,000 legally registered foreign residents at the end of 1996. A large proportion of these are in Prague - 35% of the total in December 1996. The aim of this project was to enrich the fund of information concerning the "environment", reasons and "mechanisms" behind immigration to the Czech Republic. Mr. Drbohlav looked first at the empirical situation and on this basis set out to test certain well-known migration theories. He focused on four main areas: 1) a detailed description and explanation of the stock of foreign citizens legally settled in Czech territory, concentrating particularly on "economic" migrants; 2) a questionnaire survey targeting a total of 192 Ukrainian workers (98 in the fall 1995 and 94 in the fall 1996) working in Prague or its vicinity; 3) a second questionnaire survey of 40 "western" firms (20 in 1996 and 20 in 1997) operating out of Prague; 4) an opinion poll on how the Czech population reacts to foreign workers in the CR. Over 80% of economic immigrants at the end of 1996 were from European countries, 16% from Asia and under 2% from North America. The largest single nationalities were Ukrainians, Slovaks, Vietnamese and Poles. There has been a huge increase in the Ukrainian immigrant community over both space (by region) and time (a ten-fold increase since 1993), and at 40,000 persons this represents one third of all legal immigrants. Indications are that many more live and work there illegally. Young males with low educational/skills levels predominate, in contrast with the more heterogeneous immigration from the "West". The primary reason for this migration is the higher wages in the Czech Republic. In 1994 the relative figures of GDP adjusted for parity of purchasing power were US$ 8,095 for the Czech Republic versus US$ 3,330 for the Ukraine as a whole and US$ 1,600 for the Zakarpatye region from which 49% of the respondents in the survey came. On an individual level, the average Czech wage is about US$ 330 per month, while 50% of the Ukrainian respondents put their last monthly wage before leaving for the Czech Republic at under US$ 27. The very low level of unemployment in the latter country (fluctuating around 4%) was also mentioned as an important factor. Migration was seen as a way of diversifying the family's source of income and 49% of the respondents had made their plans together with partners or close relatives, while 45% regularly send remittances to Ukraine (94% do so through friends or relatives). Looking at Ukrainian migration from the point of view of the dual market theory, these migrants' type and conditions of work, work load and earnings were all significantly worse than in the primary sector, which employs well educated people and offers them good earnings, job security and benefits. 53% of respondents were working and/or staying in the Czech Republic illegally at the time of the research, 73% worked as unqualified, unskilled workers or auxiliary workers, 62% worked more than 12 hours a day, and 40% evaluated their working conditions as hard. 51% had no days off, earnings were low in relation to the number of hours worked. and 85% said that their earnings did not increase over time. Nearly half the workers were recruited in Ukraine and only 4% expressed a desire to stay in the Czech Republic. Network theories were also borne out to some extent as 33% of immigrants came together with friends from the same village, town or region in Ukraine. The number who have relatives working in the Czech Republic is rising, and many wish to invite relatives or children to visit them. The presence of organisations which organised cross-border migration, including some which resort to organising illegal documents, also gives some support for the institutional theory. Mr. Drbohlav found that all the migration theories considered offered some insights on the situation, but that none was sufficient to explain it all. He also points out parallels with many other regions of the world, including Central America, South and North America, Melanesia, Indonesia, East Africa, India, the Middle East and Russia. For the survey of foreign and international firms, those chosen were largely from countries represented by more than one company and were mainly active in market services such as financial and trade services, marketing and consulting. While 48% of the firms had more than 10,000 employees spread through many countries, more than two thirds had fewer than 50 employees in the Czech Republic. Czechs formed 80% plus of general staff in these firms although not more than 50% of senior management, and very few other "easterners" were employed. All companies absolutely denied employing people illegally. The average monthly wage of Czech staff was US$ 850, with that of top managers from the firm's "mother country" being US$ 6,350 and that of other western managers US$ 3,410. The foreign staff were generally highly mobile and were rarely accompanied by their families. Most saw their time in the Czech Republic as positive for their careers but very few had any intention of remaining there. Factors in the local situation which were evaluated positively included market opportunities, the economic and political environment, the quality of technical and managerial staff, and cheap labour and low production costs. In contrast, the level of appropriate business ethics and conduct, the attitude of local and regional authorities, environmental production conditions, the legal environment and financial markets and fiscal policy were rated very low. In the final section of his work Mr. Drbohlav looked at the opinions expressed by the local Czech population in a poll carried out at the beginning of 1997. This confirmed that international labour migration has become visible in this country, with 43% of respondents knowing at least one foreigner employed by a Czech firm in this country. Perception differ according to the region from which the workers come and those from "the West" are preferred to those coming from further east. 49% saw their attitude towards the former as friendly but only 20% felt thus towards the latter. Overall, attitudes towards migrant workers is neutral, although 38% said that such workers should not have the same rights as Czech citizens. Sympathy towards foreign workers tends to increase with education and the standard of living, and the relatively positive attitudes towards foreigners in the South Bohemia region contradicted the frequent belief that a lack of experience of international migration lowers positive perceptions of it.

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Quantifying the health effects associated with simultaneous exposure to many air pollutants is now a research priority of the US EPA. Bayesian hierarchical models (BHM) have been extensively used in multisite time series studies of air pollution and health to estimate health effects of a single pollutant adjusted for potential confounding of other pollutants and other time-varying factors. However, when the scientific goal is to estimate the impacts of many pollutants jointly, a straightforward application of BHM is challenged by the need to specify a random-effect distribution on a high-dimensional vector of nuisance parameters, which often do not have an easy interpretation. In this paper we introduce a new BHM formulation, which we call "reduced BHM", aimed at analyzing clustered data sets in the presence of a large number of random effects that are not of primary scientific interest. At the first stage of the reduced BHM, we calculate the integrated likelihood of the parameter of interest (e.g. excess number of deaths attributed to simultaneous exposure to high levels of many pollutants). At the second stage, we specify a flexible random-effect distribution directly on the parameter of interest. The reduced BHM overcomes many of the challenges in the specification and implementation of full BHM in the context of a large number of nuisance parameters. In simulation studies we show that the reduced BHM performs comparably to the full BHM in many scenarios, and even performs better in some cases. Methods are applied to estimate location-specific and overall relative risks of cardiovascular hospital admissions associated with simultaneous exposure to elevated levels of particulate matter and ozone in 51 US counties during the period 1999-2005.

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The past decade has witnessed a period of intense economic globalisation. The growing significance of international trade, investment, production and financial flows appears to be curtailing the autonomy of individual nation states. In particular, globalisation appears to be encouraging, if not demanding, a decline in social spending and standards. However, many authors believe that this thesis ignores the continued impact of national political and ideological pressures and lobby groups on policy outcomes. In particular, it has been argued that national welfare consumer and provider groups remain influential defenders of the welfare state. For example, US aged care groups are considered to be particularly effective defenders of social security pensions. According to this argument, governments engaged in welfare retrenchment may experience considerable electoral backlash (Pierson 1996; Mishra 1999). Yet, it is also noted that governments can take action to reduce the impact of such groups by reducing their funding, and their access to policy-making and consultation processes. These actions are then justified on the basis of removing potential obstacles to economic competitiveness (Pierson 1994; Melville 1999).

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We present a vertically resolved zonal mean monthly mean global ozone data set spanning the period 1901 to 2007, called HISTOZ.1.0. It is based on a new approach that combines information from an ensemble of chemistry climate model (CCM) simulations with historical total column ozone information. The CCM simulations incorporate important external drivers of stratospheric chemistry and dynamics (in particular solar and volcanic effects, greenhouse gases and ozone depleting substances, sea surface temperatures, and the quasi-biennial oscillation). The historical total column ozone observations include ground-based measurements from the 1920s onward and satellite observations from 1970 to 1976. An off-line data assimilation approach is used to combine model simulations, observations, and information on the observation error. The period starting in 1979 was used for validation with existing ozone data sets and therefore only ground-based measurements were assimilated. Results demonstrate considerable skill from the CCM simulations alone. Assimilating observations provides additional skill for total column ozone. With respect to the vertical ozone distribution, assimilating observations increases on average the correlation with a reference data set, but does not decrease the mean squared error. Analyses of HISTOZ.1.0 with respect to the effects of El Niño–Southern Oscillation (ENSO) and of the 11 yr solar cycle on stratospheric ozone from 1934 to 1979 qualitatively confirm previous studies that focussed on the post-1979 period. The ENSO signature exhibits a much clearer imprint of a change in strength of the Brewer–Dobson circulation compared to the post-1979 period. The imprint of the 11 yr solar cycle is slightly weaker in the earlier period. Furthermore, the total column ozone increase from the 1950s to around 1970 at northern mid-latitudes is briefly discussed. Indications for contributions of a tropospheric ozone increase, greenhouse gases, and changes in atmospheric circulation are found. Finally, the paper points at several possible future improvements of HISTOZ.1.0.

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While the pathology peer review/pathology working group (PWG) model has long been used in mammalian toxicologic pathology to ensure the accuracy, consistency, and objectivity of histopathology data, application of this paradigm to ecotoxicological studies has thus far been limited. In the current project, the PWG approach was used to evaluate histopathologic sections of gills, liver, kidney, and/or intestines from three previously published studies of diclofenac in trout, among which there was substantial variation in the reported histopathologic findings. The main objectives of this review process were to investigate and potentially reconcile these interstudy differences, and based on the results, to establish an appropriate no observed effect concentration (NOEC). Following a complete examination of all histologic sections and original diagnoses by a single experienced fish pathologist (pathology peer review), a two-day PWG session was conducted to allow members of a four-person expert panel to determine the extent of treatment-related findings in each of the three trout studies. The PWG was performed according to the United States Environmental Protection Agency (US EPA) Pesticide Regulation (PR) 94-5 (EPA Pesticide Regulation, 1994). In accordance with standard procedures, the PWG review was conducted by the non-voting chairperson in a manner intended to minimize bias, and thus during the evaluation, the four voting panelists were unaware of the treatment group status of individual fish and the original diagnoses associated with the histologic sections. Based on the results of this review, findings related to diclofenac exposure included minimal to slightly increased thickening of the gill filament tips in fish exposed to the highest concentration tested (1,000 μg/L), plus a previously undiagnosed finding, decreased hepatic glycogen, which also occurred at the 1,000 μg/L dose level. The panel found little evidence to support other reported effects of diclofenac in trout, and thus the overall NOEC was determined to be >320 μg/L. By consensus, the PWG panel was able to identify diagnostic inconsistencies among and within the three prior studies; therefore this exercise demonstrated the value of the pathology peer review/PWG approach for assessing the reliability of histopathology results that may be used by regulatory agencies for risk assessment.

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OBJECTIVE To evaluate the correlation between clinical measures of disease activity and a ultrasound (US) scoring system for synovitis applied by many different ultrasonographers in a daily routine care setting within the Swiss registry for RA (SCQM) and further to determine the sensitivity to change of this US Score. METHODS One hundred and eight Swiss rheumatologists were trained in performing the Swiss Sonography in Arthritis and Rheumatism (SONAR) score. US B-mode and Power Doppler (PwD) scores were correlated with DAS28 and compared between the clinical categories in a cross-sectional cohort of patients. In patients with a second US (longitudinal cohort), we investigated if change in US score correlated with change in DAS and evaluated the responsiveness of both methods. RESULTS In the cross-sectional cohort with 536 patients, correlation between the B-mode score and DAS28 was significant but modest (Pearson coefficient r = 0.41, P < 0.0001). The same was true for the PwD score (r = 0.41, P < 0.0001). In the longitudinal cohort with 183 patients we also found a significant correlation between change in B-mode and in PwD score with change in DAS28 (r = 0.54, P < 0.0001 and r = 0.46, P < 0.0001, respectively). Both methods of evaluation (DAS and US) showed similar responsiveness according to standardized response mean (SRM). CONCLUSIONS The SONAR Score is practicable and was applied by many rheumatologists in daily routine care after initial training. It demonstrates significant correlations with the degree of as well as change in disease activity as measured by DAS. On the level of the individual, the US score shows many discrepancies and overlapping results exist.

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There is currently much interest in the appropriate use of obstetrical technology, cost containment and meeting consumers' needs for safe and satisfying maternity care. At the same time, there has been an increase in professionally unattended home births. In response, a new type of service, the out-of-hospital childbearing center (CBC) has been developed which is administratively and structurally separate from the hospital. In the CBC, maternity care is provided by certified nurse-midwives to carefully screened low risk childbearing families in conjunction with physician and hospital back-up.^ It was the purpose of this study to accomplish the following objectives: (1) To describe in a historical prospective study the demographic and medical-obstetric characteristics of patients laboring in eleven selected out-of-hospital childbearing centers in the United States from May 1, 1972, to December 15, 1979. Labor is defined as the onset of regular contractions as determined by the patient. (2) To describe any differences between those patients who require transfer to a back-up hospital and those who do not. (3) To describe administrative and service characteristics of eleven selected out-of-hospital childbearing centers in the United States. (4) To compare the demographic and medical-obstetric characteristics of women laboring in eleven selected out-of-hospital childbearing centers with a national sample of women of similar obstetric risk who according to birth certificates delivered legitimate infants in a hospital setting in the United States in 1972.^ Research concerning CBCs and supportive to the development of CBCs including studies which identified factors associated with fetal and perinatal morbidity and mortality, obstetrical risk screening, and the progress of technological development in obstetrics were reviewed. Information concerning the organization and delivery of care at each selected CBC was also collected and analyzed.^ A stratified, systematic sample of 1938 low risk women who began labor in a selected CBC were included in the study. These women were not unlike those described previously in small single center studies reported in the literature. The mean age was 25 years. Sixty-three per cent were white, 34 per cent Hispanic, 88 per cent married, 45 per cent had completed at least two years of college, nearly one-third were professionals and over a third were housewives. . . . (Author's abstract exceeds stipulated maximum length. Discontinued here with permission of school.) UMI ^

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Data on distribution of dissolved and particulate organic matter obtained during Cruises 21 and 24 of R/V Akademik A. Nesmeyanov in June-August 1992 and 1993 are presented. In general a remarkable heterogeneity in distributions of both dissolved and particulate organic carbon is revealed. Concentrations of dissolved organic carbon vary from 98 to 700 µmol/l and those of particulate organic carbon vary from 3 to 50 µmol/l. Maximum concentrations are commonly observed in the shelf region while minimum concentrations - in the central basin. Run-off of the Amur River raises dissolved matter concentration in the Sakhalin Bay, while oil exploitation at the Sakhalin shelf maximizes particulate organic carbon concentration and minimizes dissolved one. Concentrations of dissolved and particulate organic carbon in the surface microlayer were estimated for the first time and are shown to be 1.5-2.0 times higher than in surface waters.