996 resultados para Extended states


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A new graph-based construction of generalized low density codes (GLD-Tanner) with binary BCH constituents is described. The proposed family of GLD codes is optimal on block erasure channels and quasi-optimal on block fading channels. Optimality is considered in the outage probability sense. Aclassical GLD code for ergodic channels (e.g., the AWGN channel,the i.i.d. Rayleigh fading channel, and the i.i.d. binary erasure channel) is built by connecting bitnodes and subcode nodes via a unique random edge permutation. In the proposed construction of full-diversity GLD codes (referred to as root GLD), bitnodes are divided into 4 classes, subcodes are divided into 2 classes, and finally both sides of the Tanner graph are linked via 4 random edge permutations. The study focuses on non-ergodic channels with two states and can be easily extended to channels with 3 states or more.

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This study provides a comparative economic analysis of the primary production of pork and its marketing channel in Spain and the United States. The focus on Spain is due to the profound growth and transformation of its pork sector over the last 20 years, compared with other major players in the world market for pig meat. The analysis reveals a number of similar characteristics but also important differences between the two countries. The significant expansion of Spain’s pork production sector stemmed from a number of factors that apply, to a relatively large extent, to some U.S. states (in particular, North Carolina) but do not apply to the U.S. pork production sector as a whole. This implies that it is unlikely that the U.S. pork production sector as a whole will mimic an expansion driven by the same type of factors in the future. Likewise, it seems highly unlikely that the U.S. consumption of pig meat will expand in the future based on the same driving forces behind the sharp increase in Spain’s domestic demand for pig meat over the last 20 years. The analysis also indicates that Spanish pig producers are currently being subjected to more stringent environmental and animal welfare regulations than their U.S. counterparts and that these regulations are becoming increasingly more restrictive. It would not be surprising to see similar trends emerging in the United States, leading to a substantially more restrictive regulatory environment for U.S. hog producers.

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PURPOSE: To analyze outcomes after right portal vein embolization extended to segment IV (right PVE + IV) before extended right hepatectomy, including liver hypertrophy, resection rates, and complications after embolization and resection, and to assess differences in outcomes with two different particulate embolic agents. MATERIALS AND METHODS: Between 1998 and 2004, transhepatic ipsilateral right PVE + IV with particles and coils was performed in 44 patients with malignant hepatobiliary disease, including metastases (n = 24), biliary cancer (n = 14), and hepatocellular carcinoma (n = 6). Right PVE + IV was considered if the future liver remnant (FLR; segments II/III with or without I) was less than 25% of the total estimated liver volume (TELV). Tris-acryl microspheres (100-700 microm; n = 21) or polyvinyl alcohol (PVA) particles (355-1,000 microm; n = 23) were administered in a stepwise fashion. Smaller particles were used to occlude distal branches, followed by larger particles to occlude proximal branches until near-complete stasis. Coils were then placed in secondary portal branches. Computed tomographic volumetry was performed before and 3-4 weeks after right PVE + IV to assess FLR hypertrophy. Liver volumes and postembolization and postoperative outcomes were measured. RESULTS: After right PVE + IV with PVA particles, FLR volume increased 45.5% +/- 40.9% and FLR/TELV ratio increased 6.9% +/- 5.6%. After right PVE + IV with tris-acryl microspheres, FLR volume increased 69.0% +/- 30.7% and FLR/TELV ratio increased 9.7% +/- 3.3%. Differences in FLR volume (P = .0011), FLR/TELV ratio (P = .027), and resection rates (P = .02) were statistically significant. Seventy-one percent of patients underwent extended right hepatectomy (86% after receiving tris-acryl microspheres, 57% after receiving PVA). Thirteen patients (29%) did not undergo resection (extrahepatic spread [n = 9], inadequate hypertrophy [n = 3], other reasons [n = 1]). No patient developed postembolization syndrome or progressive liver insufficiency after embolization or resection. One death after resection occurred as a result of sepsis and hemorrhage. Median hospital stays were 1 day after right PVE + IV and 7 days after resection. CONCLUSION: Transhepatic ipsilateral right PVE + IV with use of particles and coils is a safe, effective method for inducing contralateral hypertrophy before extended right hepatectomy. Embolization with small spherical particles provides improved hypertrophy and resection rates compared with larger, nonspherical particles.

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The European Union (EU) accomplished its biggest enlargement process in 2004 in terms of the number of countries, area, and population. This study focuses on the impact of enlargement, the resulting technology transfer on the grain sectors of the New Member States (NMS), and the consequent welfare implications. The study finds that EU enlargement has important implications for the EU and the NMS, but its impact on the world grain markets is minimal. The results show that producers in the NMS gain from accession because of higher prices, whereas consumers in most NMS face a welfare loss. Incorporating technology transfer into the accession increases the welfare gain of producers despite falling prices because of the larger supply shift. The loss of welfare for consumers in most NMS is lower in this case because of the decline in grain prices.

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(-)-1-(3,4-Dimethoxyphenetylamino)-3-(3,4-dihydroxy)-2-propanol [(-)-RO363] is a highly selective beta(1)-adrenergic receptor (beta(1)AR) agonist. To study the binding site of beta(1)-selective agonist, chimeric beta(1)/beta(2)ARs and Ala-substituted beta(1)ARs were constructed. Several key residues of beta(1)AR [Leu(110) and Thr(117) in transmembrane domain (TMD) 2], and Phe(359) in TMD 7] were found to be responsible for beta(1)-selective binding of (-)-RO363, as determined by competitive binding. Based on these results, we built a three-dimensional model of the binding domain for (-)-RO363. The model indicated that TMD 2 and TMD 7 of beta(1)AR form a binding pocket; the methoxyphenyl group of N-substituent of (-)-RO363 seems to locate within the cavity surrounded by Leu(110), Thr(117), and Phe(359). The amino acids Leu(110) and Phe(359) interact with the phenyl ring of (-)-RO363, whereas Thr(117) forms hydrogen bond with the methoxy group of (-)-RO363. To examine the interaction of these residues with beta(1)AR in an active state, each of the amino acids was changed to Ala in a constitutively active (CA)-beta(1)AR mutant. The degree of decrease in the affinity of CA-beta(1)AR for (-)-RO363 was essentially the same as that of wild-type beta(1)AR when mutated at Leu(110) and Thr(117). However, the affinity was decreased in Ala-substituted mutant of Phe(359) compared with that of wild-type beta(1)AR. These results indicated that Leu(110) and Thr(117) are necessary for the initial binding of (-)-RO363 with beta(1)-selectivity, and interaction of Phe(359) with the N-substituent of (-)-RO363 in an active state is stronger than in the resting state.

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The therapeutic efficacy of BAL9141 (formerly Ro 63-9141), a novel cephalosporin with broad in vitro activity that also has activity against methicillin-resistant Staphylococcus aureus (MRSA), was investigated in rats with experimental endocarditis. The test organisms were homogeneously methicillin-resistant S. aureus strain COL transformed with the penicillinase-encoding plasmid pI524 (COL Bla+) and homogeneously methicillin-resistant, penicillinase-producing isolate P8-Hom, selected by serial exposure of parent strain P8 to methicillin. The MICs of BAL9141 for these organisms (2 mg/liter) were low, and BAL9141was bactericidal in time-kill curve studies after 24 h of exposure to either two, four, or eight times the MIC. Rats with experimental endocarditis were treated in a three-arm study with a continuous infusion of BAL5788 (formerly Ro 65-5788), a carbamate prodrug of BAL9141, or with amoxicillin-clavulanate or vancomycin. The rats were administered BAL9141 to obtain steady-state target levels of 20, 10, and 5 mg of per liter or were administered either 1.2 g of amoxicillin-clavulanate (ratio 5:1) every 6 h or 1 g of vancomycin every 12 h at changing flow rates to simulate the pharmacokinetics produced in humans by intermittent intravenous treatment. Treatment was started 12 h after bacterial challenge and lasted for 3 days. BAL9141 was successful in the treatment of experimental endocarditis due to either MRSA isolate COL Bla+ or MRSA isolate P8-Hom at the three targeted steady-state concentrations and sterilized >90% of cardiac vegetations (P < 0.005 versus controls; P < 0.05 versus amoxicillin-clavulanate and vancomycin treatment groups). These promising in vivo results with BAL9141 correlated with the high affinity of the drug for PBP 2a and its stability to penicillinase hydrolysis observed in vitro.

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In this day of the mature highway systems, a new set of problems is facing the highway engineer. The existing infrastructure has aged to or past the design life of the original pavement design. In many cases, increased commercial traffic is creating the need for additional load carrying capacity, causing state highway engineers to consider new alternatives for rehabilitation of existing surfaces. Alternative surface materials, thicknesses, and methods of installation must be identified to meet the needs of individual pavements and budgets. With overlays being one of the most frequently used rehabilitation alternatives, it is important to learn more about the limitations and potential performance of thin bonded portland cement overlays and subsequent rehabilitation. The Iowa ultra-thin project demonstrated the application of thin portland cement concrete overlays as a rehabilitation technique. It combined the variables of base preparation, overlay thickness, slab size, and fiber enhancement into a series of test sections over a 7.2-mile length. This report identifies the performance of the overlays in terms of deflection reduction, reduced cracking, and improved bonding between the portland cement concrete (PCC) and asphalt cement concrete (ACC) base layers. The original research project was designed to evaluate the variables over a 5-year period of time. A second project provided the opportunity to test overlay rehabilitation techniques and continue measurement of the original overlay performance for 5 additional years. All performance indicators identified exceptional performance over the 10-year evaluation period for each of the variable combinations considered. The report summarizes the research methods, results, and identifies future research ideas to aid the pavement overlay designer in the successful implementation of ultra-thin portland cement concrete overlays as an lternative pavement rehabilitation technique.

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DP1, a dimerization partner protein of the transcription factor E2F, is known to inhibit Wnt/β-catenin signalling along with E2F, although the function of DP1 itself was not well characterized. Here, we present a novel dual regulatory mechanism of Wnt/β-catenin signalling by DP1 independent from E2F. DP1 negatively regulates Wnt/β-catenin signalling by inhibiting Dvl-Axin interaction and by enhancing poly-ubiquitination of β-catenin. In contrast, DP1 positively modulates the signalling upon Wnt stimulation, via increasing cytosolic β-catenin and antagonizing the kinase activity of NLK. In Xenopus embryos, DP1 exerts both positive and negative roles in Wnt/β-catenin signalling during anteroposterior neural patterning. From subcellular localization analyses, we suggest that the dual roles of DP1 in Wnt/β-catenin signalling are endowed by differential nucleocytoplasmic localizations. We propose that these dual functions of DP1 can promote and stabilize biphasic Wnt-on and Wnt-off states in response to a gradual gradient of Wnt/β-catenin signalling to determine differential cell fates.

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We present a polyhedral framework for establishing general structural properties on optimal solutions of stochastic scheduling problems, where multiple job classes vie for service resources: the existence of an optimal priority policy in a given family, characterized by a greedoid (whose feasible class subsets may receive higher priority), where optimal priorities are determined by class-ranking indices, under restricted linear performance objectives (partial indexability). This framework extends that of Bertsimas and Niño-Mora (1996), which explained the optimality of priority-index policies under all linear objectives (general indexability). We show that, if performance measures satisfy partial conservation laws (with respect to the greedoid), which extend previous generalized conservation laws, then the problem admits a strong LP relaxation over a so-called extended greedoid polytope, which has strong structural and algorithmic properties. We present an adaptive-greedy algorithm (which extends Klimov's) taking as input the linear objective coefficients, which (1) determines whether the optimal LP solution is achievable by a policy in the given family; and (2) if so, computes a set of class-ranking indices that characterize optimal priority policies in the family. In the special case of project scheduling, we show that, under additional conditions, the optimal indices can be computed separately for each project (index decomposition). We further apply the framework to the important restless bandit model (two-action Markov decision chains), obtaining new index policies, that extend Whittle's (1988), and simple sufficient conditions for their validity. These results highlight the power of polyhedral methods (the so-called achievable region approach) in dynamic and stochastic optimization.

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Objective: To assess the importance of spirituality and religious coping among outpatients with a DSM-IV diagnosis of schizophrenia or schizoaffective disorder living in three countries. Method: A total of 276 outpatients (92 from Geneva, Switzerland, 121 from Trois-Rivières, Canada, and 63 from Durham, North Carolina), aged 18-65, were administered a semi-structured interview on the role of spirituality and religiousness in their lives and to cope with their illness. Results: Religion is important for outpatients in each of the three country sites, and religious involvement is higher than in the general population. Religion was helpful (i.e., provided a positive sense of self and positive coping with the illness) among 87% of the participants and harmful (a source of despair and suffering) among 13%. Helpful religion was associated with better social, clinical and psychological status. The opposite was observed for the harmful aspects of religion. In addition, religion sometimes conflicted with psychiatric treatment. Conclusions: These results indicate that outpatients with schizophrenia or schizoaffective disorder often use spirituality and religion to cope with their illness, basically positively, yet sometimes negatively. These results underscore the importance of clinicians taking into account the spiritual and religious lives of patients with schizophrenia.

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How people choose to live depends on a variety of social and economic circumstances. Single family dwellings, extended family compounds, and communal apartment blocks are all forms of residential architecture that have ancient roots and occur in every culture. Each form both reflects and affects the living styles of the people who reside there. The double house, which shelters two families in units separated by a wall or floor, balances the convenience of an apartment with the psychological comforts of a home. During the mid to late nineteenth and early twentieth centuries in the United States, the double house was hugely popular in some cities, such as Minneapolis and Milwaukee, but only a minimal presence in Des Moines

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The current issue of deportation is a global concern that is demanding the attention of human rights leaders, activists and global citizens. Small island nations, such as, the Cape Verde Islands, are experiencing difficulties reintegrating deported immigrants arriving from both the United States and Europe. According to the Consulate of Cape Verde’s database, one Cape Verdean immigrant was deported in 1987. Twenty years later, 108 deportation cases are pending—the highest number of pending cases to date. This issue is a reflection of the Western countries’ immigration and human rights policies that are affecting many developing countries. This capstone research focuses primarily on the reintegration program managed by the Cape Verdean government, the reintegration process of the deported immigrants from the United States and the islanders’ experiences throughout this process. This issue is examined through the eyes of a Cape Verdean immigrant living in the United States witnessing first hand the negative impacts these immigration policies have had, and continue to have, in the Cape Verdean community in the United States and in Cape Verde. Research was collected through various formal and informal interviews and published documents on this topic. Analysis of the data has revealed that the government’s reintegration program is experiencing difficulties with implementation and financial sustainability. Moreover, the deportees’ reintegration experience varied based on access to government assistance and their interaction with island residents. Subsequently, it is recommended that the reintegration program be evaluated with the purpose to reorganize under new leadership.

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The problem of small Island Developing States (SIDS) is quite recent, end of the 80s and 90s, still looking for a theoretical consolidation. SIDS, as small states in development, formed by one or several islands geographically dispersed, present reduced population, market, territory, natural resources, including drinkable water, and, in great number of the cases, low level of economic activity, factors that together, hinder the gathering of scale economies. To these diseconomies they come to join the more elevated costs in transports and communications which, allies to lower productivities, to a smaller quality and diversification of its productions, which difficult its integration in the world economy. In some SIDS these factors are not dissociating of the few investments in infrastructures, in the formation of human resources and in productive investments, just as it happens in most of the developing countries. In ecological terms, many of them with shortage of natural resources, but integrating important ecosystems in national and world terms, but with great fragility relatively to the pollution action, of excessive fishing, of uncontrolled development of tourism, factors that, conjugated and associated to the stove effect, condition the climate and the slope of the medium level of the sea water and therefore could put in cause the own survival of some of them. The drive to the awareness of the international community towards its problems summed up with the accomplishment by the United Nations in the Barbados’s Conference, 1994 where the right to the development was emphasized, through the going up the appropriate strategies and the Programme of Action for the Sustainable Development of the SIDS. The orientation of the regional and international cooperation in that sense, sharing technology (namely clean technology and control and administration environmental technology), information and creation of capacity-building, supplying means, including financial resources, creating non discriminatory and just trade rules, it would drive to the establishment of a world system economically more equal, in which the production, the consumption, the pollution levels, the demographic politics were guided towards the sustainability. It constituted an important step for the recognition for the international community on the specificities of those states and it allowed the definition of a group of norms and politics to implement at the national, regional and international level and it was important that they continued in the sense of the sustainable development. But this Conference had in its origin previous summits: the Summit of Rio de Janeiro about Environment and Development, accomplished in 1992, which left an important document - the Agenda 21, in the Conference of Stockholm at 1972 and even in the Conference of Ramsar, 1971 about “Wetlands.” CENTRO DE ESTUDOS AFRICANOS Occasional Papers © CEA - Centro de Estudos Africanos 4 Later, the Valletta Declaration, Malta, 1998, the Forum of Small States, 2002, get the international community's attention for the problems of SIDS again, in the sense that they act to increase its resilience. If the definition of “vulnerability” was the inability of the countries to resist economical, ecological and socially to the external shocks and “resilience” as the potential for them to absorb and minimize the impact of those shocks, presenting a structure that allows them to be little affected by them, a part of the available studies, dated of the 90s, indicate that the SIDS are more vulnerable than the other developing countries. The vulnerability of SIDS results from the fact the they present an assemblage of characteristics that turns them less capable of resisting or they advance strategies that allow a larger resilience to the external shocks, either anthropogenic (economical, financial, environmental) or even natural, connected with the vicissitudes of the nature. If these vulnerability factors were grouped with the expansion of the economic capitalist system at world level, the economic and financial globalisation, the incessant search of growing profits on the part of the multinational enterprises, the technological accelerated evolution drives to a situation of disfavour of the more poor. The creation of the resilience to the external shocks, to the process of globalisation, demands from SIDS and of many other developing countries the endogen definition of strategies and solid but flexible programs of integrated development. These must be assumed by the instituted power, but also by the other stakeholders, including companies and organizations of the civil society and for the population in general. But that demands strong investment in the formation of human resources, in infrastructures, in investigation centres; it demands the creation capacity not only to produce, but also to produce differently and do international marketing. It demands institutional capacity. Cape Verde is on its way to this stage.