952 resultados para Monopolization or attempt of monopolization


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OBJECTIVES To investigate the frequency of interim analyses, stopping rules, and data safety and monitoring boards (DSMBs) in protocols of randomized controlled trials (RCTs); to examine these features across different reasons for trial discontinuation; and to identify discrepancies in reporting between protocols and publications. STUDY DESIGN AND SETTING We used data from a cohort of RCT protocols approved between 2000 and 2003 by six research ethics committees in Switzerland, Germany, and Canada. RESULTS Of 894 RCT protocols, 289 prespecified interim analyses (32.3%), 153 stopping rules (17.1%), and 257 DSMBs (28.7%). Overall, 249 of 894 RCTs (27.9%) were prematurely discontinued; mostly due to reasons such as poor recruitment, administrative reasons, or unexpected harm. Forty-six of 249 RCTs (18.4%) were discontinued due to early benefit or futility; of those, 37 (80.4%) were stopped outside a formal interim analysis or stopping rule. Of 515 published RCTs, there were discrepancies between protocols and publications for interim analyses (21.1%), stopping rules (14.4%), and DSMBs (19.6%). CONCLUSION Two-thirds of RCT protocols did not consider interim analyses, stopping rules, or DSMBs. Most RCTs discontinued for early benefit or futility were stopped without a prespecified mechanism. When assessing trial manuscripts, journals should require access to the protocol.

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OBJECTIVES The main objective was to assess the credibility of the evidence using Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) in oral health systematic reviews on the Cochrane Database of Systematic Reviews (CDSR) and elsewhere. STUDY DESIGN AND SETTING Systematic Reviews or meta-analyses (January 2008-December 2013) from 14 high impact general dental and specialty dental journals and the Cochrane Database of Systematic Reviews were screened for meta-analyses. Data was collected at the systematic review, meta-analysis and trial level. Two reviewers applied and agreed on the GRADE rating for the selected meta-analyses. RESULTS From the 510 systematic reviews initially identified 91 reviews (41 Cochrane and 50 non-Cochrane) were eligible for inclusion. The quality of evidence was high in 2% and moderate in 18% of the included meta-analyses with no difference between Cochrane and non-Cochrane reviews, journal impact factor or year of publication. The most common domains prompting downgrading of the evidence were study limitations (risk of bias) and imprecision (risk of play of chance). CONCLUSION The quality of the evidence in oral health assessed using GRADE is predominantly low or very low suggesting a pressing need for more randomised clinical trials and other studies of higher quality in order to inform clinical decisions thereby reducing the risk of instituting potentially ineffective and/or harmful therapies.

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In a marvelous but somewhat neglected paper, 'The Corporation: Will It Be Managed by Machines?' Herbert Simon articulated from the perspective of 1960 his vision of what we now call the New Economy the machine-aided system of production and management of the late twentieth century. Simon's analysis sprang from what I term the principle of cognitive comparative advantage: one has to understand the quite different cognitive structures of humans and machines (including computers) in order to explain and predict the tasks to which each will be most suited. Perhaps unlike Simon's better-known predictions about progress in artificial intelligence research, the predictions of this 1960 article hold up remarkably well and continue to offer important insights. In what follows I attempt to tell a coherent story about the evolution of machines and the division of labor between humans and machines. Although inspired by Simon's 1960 paper, I weave many other strands into the tapestry, from classical discussions of the division of labor to present-day evolutionary psychology. The basic conclusion is that, with growth in the extent of the market, we should see humans 'crowded into' tasks that call for the kinds of cognition for which humans have been equipped by biological evolution. These human cognitive abilities range from the exercise of judgment in situations of ambiguity and surprise to more mundane abilities in spatio-temporal perception and locomotion. Conversely, we should see machines 'crowded into' tasks with a well-defined structure. This conclusion is not based (merely) on a claim that machines, including computers, are specialized idiots-savants today because of the limits (whether temporary or permanent) of artificial intelligence; rather, it rests on a claim that, for what are broadly 'economic' reasons, it will continue to make economic sense to create machines that are idiots-savants.

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Introduction. The prevalence of overweight and obesity has increased sharply for both adults and children, particularity in disadvantaged populations. Changes in dietary habits are small; however applying behavior-change principles has been associated with weight loss and preventing weight gain. This article will review studies targeting economically disadvantaged and/or communities of color incorporating the Transtheoretical Model of Change (TTM).^ Methods. Inclusion criteria were established. Descriptions of characteristics of the reviewed study interventions are included.^ Results. The search yielded a total of 23 articles identified through the electronic database PubMed that included Transtheoretical Model of Change (TTM) interventions regarding diet and/or nutrition, physical activity and/or exercise in disadvantaged populations. Thirteen study interventions centered solely on diet modification, five focused only on physical activity, and five concentrated on a combination of both. The preponderance of studies targeted WIC and urban recipients.^ Discussion/Conclusion. Although the majority of intervention studies supported the use of the Transtheoretical Model of Change (TTM) for weight loss and preventing weight gain, researchers noted that challenges still exist and further interventions are needed.^

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Groundwater constitutes approximately 30% of freshwater globally and serves as a source of drinking water in many regions. Groundwater sources are subject to contamination with human pathogens (viruses, bacteria and protozoa) from a variety of sources that can cause diarrhea and contribute to the devastating global burden of this disease. To attempt to describe the extent of this public health concern in developing countries, a systematic review of the evidence for groundwater microbially-contaminated at its source as risk factor for enteric illness under endemic (non-outbreak) conditions in these countries was conducted. Epidemiologic studies published in English language journals between January 2000 and January 2011, and meeting certain other criteria, were selected, resulting in eleven studies reviewed. Data were extracted on microbes detected (and their concentrations if reported) and on associations measured between microbial quality of, or consumption of, groundwater and enteric illness; other relevant findings are also reported. In groundwater samples, several studies found bacterial indicators of fecal contamination (total coliforms, fecal coliforms, fecal streptococci, enterococci and E. coli), all in a wide range of concentrations. Rotavirus and a number of enteropathogenic bacteria and parasites were found in stool samples from study subjects who had consumed groundwater, but no concentrations were reported. Consumption of groundwater was associated with increased risk of diarrhea, with odds ratios ranging from 1.9 to 6.1. However, limitations of the selected studies, especially potential confounding factors, limited the conclusions that could be drawn from them. These results support the contention that microbial contamination of groundwater reservoirs—including with human enteropathogens and from a variety of sources—is a reality in developing countries. While microbially-contaminated groundwaters pose risk for diarrhea, other factors are also important, including water treatment, water storage practices, consumption of other water sources, water quantity and access to it, sanitation and hygiene, housing conditions, and socio-economic status. Further understanding of the interrelationships between, and the relative contributions to disease risk of, the various sources of microbial contamination of groundwater can guide the allocation of resources to interventions with the greatest public health benefit. Several recommendations for future research, and for practitioners and policymakers, are presented.^

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Like other simple retroviruses the murine sarcoma virus ts110 (MuSVts110) displays an inefficient mode of genome splicing. But, unlike the splicing phenotypic of other retroviruses, the splicing event effected upon the transcript of MuSVts110 is temperature sensitive. Previous work in this laboratory has established that the conditionally defective nature of MuSVts110 RNA splicing is mediated in cis by features in the viral transcript. Here we show that the 5$\sp\prime$ splice site of the MuSVts110 transcript acts as a point of control of the overall splicing efficiency at both permissive and nonpermissive temperatures for splicing. We strengthened and simultaneously weakened the nucleotide structure of the 5$\sp\prime$ splice site in an attempt to elucidate the differential effects each of the two known critical splicing components which interact with the 5$\sp\prime$ splice site have on the overall efficiency of intron excision. We found that a transversion of the sixth nucleotide, resulting in the formation of a near-consensus 5$\sp\prime$ splice site, dramatically increased the overall efficiency of MuSVts110 RNA splicing and abrogated the thermosensitive nature of this splicing event. Various secondary mutations within this original transversion mutant, designed to selectively decrease specific splicing component interactions, lead to recovery of inefficient and thermosensitive splicing. We have further shown that a sequence of 415 nucleotides lying in the downstream exon of the viral RNA and hypothesized to act as an element in the temperature-dependent inhibition of splicing displays a functional redundancy throughout its length; loss and/or replacement of any one sequence of 100 nucleotides within this sequence does not, with one exception detailed below, diminish the degree to which MuSVts110 RNA is inhibited to splice at the restrictive temperature. One specific deletion, though, fortuitously juxtaposed and activated cryptic consensus splicing signals for the excision of a cryptic intron within the downstream exon and markedly potentiated--across a newly defined cryptic exon--the splicing event effected upon the upstream, native intron. We have exploited this mutant of MuSVts110 to further an understanding of the process of exon definition and intron definition and show that the polypyrimidine tract and consensus 3$\sp\prime$ splice site, as well as the 5$\sp\prime$ splice site, within the intron at the 3$\sp\prime$ flank of the defined exon are required for the exon's definition; implying that definition of the downstream intron is required for the in vivo definition of the proximal, upstream exon. Finally; we have shown, through the construction of heterologous mutants of MuSVts110 employing a foreign 3$\sp\prime$ end-forming sequence, that efficiency of transcript splicing can be increased--to a degree which abrogates its thermosensitive nature--in direct proportion to increasing proximity of the 3$\sp\prime$ end-forming signal to the terminal 3$\sp\prime$ splice site. ^

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Quaternary sedimentation within the Japan Sea was controlled by the configuration of peripheral sills, seasonal and long-term climatic variability, and the resultant fluctuations in sea level (Tamaki, 1988). Prior to drilling in the area, piston cores recovered from its basins contained Pleistocene sediments having distinctive color and fabric variation. Sedimentological and geochemical studies conducted on those facies indicated that the variability in fabric was the result of fluctuating marine and/or terrigenous influx to the deep-water basins of the Japan Sea (see, for example, Chough, 1984; Matoba, 1984). The sequences recovered during Leg 127 at Sites 794, 795, and 797 contain long, virtually undisturbed sequences (92.3, 123, and 119.9 mbsf [Hole 797B], respectively) of upper Miocene, upper Pliocene, and Pleistocene/Holocene sediments. The majority of these sequences consists of dark-colored (dark brown, green, and black) silty-clays, many of which are enriched in biogenic components (majority silicious, some carbonate) and/or organic matter, some containing pyrite and/or ash. These facies alternate with light-colored silty-clays, some containing ash and some showing signs of bioturbation (for example, Tamaki, Pisciotto, Allan, et al., 1990, p. 425-433). The dark-to-light sequences are present throughout the section, although they are especially dominant throughout the Pleistocene (for a more detailed lithology of Quaternary sequences recovered at Sites 794, 795, and 797, see Follmi et al. 1992 and Tada et al., 1992). This data report provides trace metal information on Pliocene-Pleistocene-Holocene samples at Sites 794,795, and 797. These data can be used (1) to provide information related to the depositional environments of the Japan Sea during the Quaternary period, (2) to permit comparisons between the dark organic-rich sediments recovered from this semi-enclosed basin and those reported for other silled basins (for example, the Mediterranean and Black seas), and (3) to permit comparisons between these sediments and contemporary equivalents found, for instance, beneath areas of high biogenic productivity. By providing such data, one should be able (1) to determine more precisely the processes governing the deposition of sediments with various levels of organic matter within enclosed basins, (2) to compare individual basin-wide processes, (3) to look for and compare the signatures present as a result of climatic fluctuation, and (4) to attempt to identify the presence and/or absence of cyclicity within such sequences.

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Existing models estimating oil spill costs at sea are based on data from the past, and they usually lack a systematic approach. This make them passive, and limits their ability to forecast the effect of the changes in the oil combating fleet or location of a spill on the oil spill costs. In this paper we make an attempt towards the development of a probabilistic and systematic model estimating the costs of clean-up operations for the Gulf of Finland. For this purpose we utilize expert knowledge along with the available data and information from literature. Then, the obtained information is combined into a framework with the use of a Bayesian Belief Networks. Due to lack of data, we validate the model by comparing its results with existing models, with which we found good agreement. We anticipate that the presented model can contribute to the cost-effective oil-combating fleet optimization for the Gulf of Finland. It can also facilitate the accident consequences estimation in the framework of formal safety assessment (FSA).

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During Ocean Drilling Program Leg 125, a thick sequence of middle Eocene to Pleistocene pelagic sediments, volcanogenic sediments, and predominantly extrusive volcanic rocks was recovered. Calcareous nannofossils were examined from 15 holes at nine sites, but Eocene to Miocene calcareous nannofossils were found only from Holes 782A, 784A, 786A, and 786B. In portions of Holes 786A and 786B, datable nannofossil oozes were found intercalated among volcanic flows. The nannofossil biostratigraphy of these holes indicates the presence of three well-defined hiatuses: within the lower Oligocene, between the upper Oligocene and middle Miocene, and between the middle and upper Miocene. An attempt was made to correlate the magnetochronological data with the first or last occurrences of the following species: Sphenolithus distentus, Reticulofenestra bisecta, Reticulofenestra reticulata, and Cyclicargolithus floridanus abisectus n. comb. The results indicate that the FO of Sphenolithus distentus can extend down to Zone CP16 (34.7 Ma), the LO of Reticulofenestra bisecta best defines the boundary between CP19a and CP19b (23.5 Ma), and the LO of Cyclicargolithus f. abisectus n. comb, can extend up to Subzone CN5a (12.5 Ma). No latest Oligocene Cyclicargolithus f. abisectus n. comb, acme was observed. Cyclicargolithus abisectus is considered a subspecies or variant of Cyclicargolithus floridanus because their LOs coincide. As a consequence of these observations, we have modified the definitions of Bukry's Subzones CP14a, CP14b, and CNla. Analyses of sediment-accumulation rates indicate that the rates increased gradually from the Eocene to Miocene. This is especially evident since the late Miocene in Hole 782A. In different parts of the Izu-Bonin forearc basin, however, the rate is not everywhere the same and appears to vary according to the import of volcanogenic materials.

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The present dataset contains the source data for Figure 2B of Tentner et al. (2012). The data shows the percentage of cultured cell-populations that stained positively and/or negatively for apoptotic markers cleaved caspase-3 and cleaved PARP, following DNA damage treatments induced by various doses of doxorubicin (0, 2 and 10 µmole/L) in the presence (100 ng/mL) or absence (0 ng/mL) of TNF-alpha co-treatment. For the six treatment conditions investigated, cell counts were made by flow cytometry at times 6, 12, 24, and 48 h following treatment; CULTURE DETAILS: U2OS cells were obtained from ATCC were maintained at 21% oxygen and 5% CO2 in Dulbecco's modified Eagle medium supplemented with 10% fetal bovine serum, penicillin, streptomycin, 2mM L-glutamine, and used within 15-20 passages. The first thymidine block was released by washing the plates three times with PBS, and incubating them in fresh thymidine-free media for 12 h. A second thymidine block was then performed by re-addition of thymidine to 2.5 mM followed by incubation for an additional 18 h. Media was aspirated, plates were washed 3 with PBS, and replaced with fresh media in the presence or absence of 10 mM aphidicolin; ANALYSIS DETAILS: See supplementary journal publication; RESULT: The authors of the supplementary journal publication conclude that TNF enhances dose-dependent cell death following doxorubicin-induced DNA damage with minimal affect on dose-dependent cell-cycle arrest.

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To date, many previous studies have viewed "Chintanakan Mai" (New Thinking), which was introduced in 1986, as one of the most important factors required for understanding present-day Laos. They tend to see the year 1986 as a watershed in Lao history and divide the history after 1975 into two periods before and after 1986: a period of socialism and a period of reform or market economy, respectively. Therefore, they are likely to see the current changes in Laos as the result or achievement of the reform started in 1986. The year 1986 is always a starting point for understanding Laos today. However, I suggest a different perspective and attempt to re-examine "Chintanakan Mai." "Chintanakan Mai" is not a watershed in Lao history, but rather a temporary slogan to advance postwar reconstruction. In this paper, I try to establish a new perspective for understanding Laos today.

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La presente tesis doctoral aborda el estudio del proyecto de vivienda colectiva social desde la noción de norma, entendida desde la sistematización o normalización de los instrumentos del proyecto arquitectónico de vivienda protegida. Esto es, desde una idea de tipificación taxonómica en cuanto ajuste a un conjunto de reglas comunes productoras de sistemas normativos. La hipótesis de partida se basa en la consideración de la vivienda pública como un laboratorio de estudio histórico de los ideales de confort y calidad de vida. Este campo de pruebas ha constituido una sólida base que ha servido como punto de encuentro muy particular entre proyecto y normativa desde las primeras vanguardias europeas hasta la actualidad. El principal objetivo de la investigación es la revalorización de una normativa de vivienda que ha producido ejemplos de innegable calidad en el contexto nacional e internacional, así como un intento de actualización de su codificación. La investigación se sirve de los instrumentos específicos de la disciplina arquitectónica para explicar una disociación detectada desde la segunda mitad del siglo pasado entre la utopía del proyecto social de vivienda y el pragmatismo de la norma que lo regula, más allá de los aspectos sociales y culturales asociados a las nuevas composiciones familiares, las tecnologías cambiantes, los ritos domésticos contemporáneos o el valor creciente del tiempo libre. La propuesta de una nueva terminología que aborde nuevas relaciones en el acercamiento al proyecto de vivienda desde la normativa española deriva en un conjunto de estrategias de proyecto desde las que proponer sistemas normativos. Dichas estrategias se basan principalmente en mecanismos de cualificación espacial que permitan un nuevo acercamiento entre dichas normas y las formas de habitar actuales. ABSTRACT This doctoral thesis deals with the study of the project of social collective housing from the notion of rule, understanding it from the systematization or standardization of the instruments of architectural project for social housing. Thus, it deals with an idea of taxonomic typification as an adjustment to a set of common rules which produce regulation systems. The initial hypothesis is based on the consideration of public housing as a laboratory for studying the historical ideals of comfort and quality of life. This testing ground has been a solid base that has served as a very specific meeting point between project and regulations from the first European avant‐garde to nowadays. The main objective of this research is the revaluation of housing regulations, which have produced examples of undeniable quality in the national and international stage, as well as an attempt to update their codification. The research assumes the specific tools of the discipline of architecture for explaining a dissociation detected between the utopia of the project for social housing and the pragmatism of the regulations from the second half of last century, beyond social and cultural aspects associated to the new family arrangements, the changing technologies, the contemporary domestic rituals or the rising value of leisure time. The proposal of a new terminology that tackles new relations in the approach to housing project from the Spanish legislation results in a set of strategies to propose regulation systems. Those strategies are mainly based on mechanisms for spatial qualification which allow a new approach between these rules and the current ways of living.

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Esta investigación avanza en el intento de recuperar la técnica tradicional del estuco a fuego, paradigma de la decoración de espacios interiores hasta la mitad del s. XX por sus imitaciones marmóreas de gran calidad. Para ejecutarlos se utilizaban morteros de cal con áridos de mármol, pigmentos minerales y grasas; con estos materiales se preparaban y tendían las masas, se pintaban al fresco y se terminaban con el paso de una herramienta metálica caliente. Como sucede con otras técnicas, el paso del tiempo ha difuminado los conocimientos sobre la materia, haciendo muy difícil la conservación o restauración de los ejemplos en nuestro patrimonio. A partir de la escasa bibliografía existente se ha recuperado el proceso, sometiendo las muestras elaboradas a diferentes ensayos que han caracterizado el acabado final,tanto en sus características intrínsecas como en las que le son conferidas al proteger finalmente las muestras con una capa de cera, tal y como se realizaba tradicionalmente.---ABSTRACT---This research advances in the attempt to recover the traditional technique of stucco by fire; paradigm of indoor decoration until half of 20th century due to its high quality marbled imitations. On its implementation process, it was used lime mortars with marble aggregates, mineral pigments and greases. With these materials, masses were prepared and extended into the walls, they were painted in fresco and ended with the passage of a heated metal tool. As with any other technique, the time passing over has blurred the knowledge on the subject, making very difficult the preservation or restoration of examples in our heritage. Despite of the limited literature, the process has been recovered; subjecting the samples prepared at different trials that have characterized the finished, both in its merits and its conferred characteristics by finally protecting the samples with a layer of wax, as was done traditionally.

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The existing seismic isolation systems are based on well-known and accepted physical principles, but they are still having some functional drawbacks. As an attempt of improvement, the Roll-N-Cage (RNC) isolator has been recently proposed. It is designed to achieve a balance in controlling isolator displacement demands and structural accelerations. It provides in a single unit all the necessary functions of vertical rigid support, horizontal flexibility with enhanced stability, resistance to low service loads and minor vibration, and hysteretic energy dissipation characteristics. It is characterized by two unique features that are a self-braking (buffer) and a self-recentering mechanism. This paper presents an advanced representation of the main and unique features of the RNC isolator using an available finite element code called SAP2000. The validity of the obtained SAP2000 model is then checked using experimental, numerical and analytical results. Then, the paper investigates the merits and demerits of activating the built-in buffer mechanism on both structural pounding mitigation and isolation efficiency. The paper addresses the problem of passive alleviation of possible inner pounding within the RNC isolator, which may arise due to the activation of its self-braking mechanism under sever excitations such as near-fault earthquakes. The results show that the obtained finite element code-based model can closely match and accurately predict the overall behavior of the RNC isolator with effectively small errors. Moreover, the inherent buffer mechanism of the RNC isolator could mitigate or even eliminate direct structure-tostructure pounding under severe excitation considering limited septation gaps between adjacent structures. In addition, the increase of inherent hysteretic damping of the RNC isolator can efficiently limit its peak displacement together with the severity of the possibly developed inner pounding and, therefore, alleviate or even eliminate the possibly arising negative effects of the buffer mechanism on the overall RNC-isolated structural responses.

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Funding: This work was funded by the Scottish Government Rural and Environment Science and Analytical Services Division. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.