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991.
In this paper we present a study about scientific production in Computer Science in Brazil and several other countries, as
measured by the number of articles in journals and conference proceedings indexed by ISI and by Scopus. We compare the Brazilian
production from 2001 to 2005 with some Latin American, Latin European, BRIC (Brazil, Russia, India, China), and other relevant
countries (South Korea, Australia and USA). We also classify and compare these countries according to the ratio of publications
in journals and conferences (the ones indexed by the two services).
The results show that Brazil has by far the largest production among Latin American countries, has a production about one
third of Spain’s, one fourth of Italy’s, and about the same as India and Russia. The growth in Brazilian publications during
the period places the country in the mid-range group and the distribution of Brazilian production according to impact factor
is similar to most countries. 相似文献
992.
Sara Bernal Irene Pelaez Laura Alias Manel Baena Juan A. De Pablo-Moreno Luis J. Serrano M. Dolores Camero Eduardo F. Tizzano Ruben Berrueco Antonio Liras 《International journal of molecular sciences》2021,22(18)
Factor V is an essential clotting factor that plays a key role in the blood coagulation cascade on account of its procoagulant and anticoagulant activity. Eighty percent of circulating factor V is produced in the liver and the remaining 20% originates in the α-granules of platelets. In humans, the factor V gene is about 80 kb in size; it is located on chromosome 1q24.2, and its cDNA is 6914 bp in length. Furthermore, nearly 190 mutations have been reported in the gene. Factor V deficiency is an autosomal recessive coagulation disorder associated with mutations in the factor V gene. This hereditary coagulation disorder is clinically characterized by a heterogeneous spectrum of hemorrhagic manifestations ranging from mucosal or soft-tissue bleeds to potentially fatal hemorrhages. Current treatment of this condition consists in the administration of fresh frozen plasma and platelet concentrates. This article describes the cases of two patients with severe factor V deficiency, and of their parents. A high level of mutational heterogeneity of factor V gene was identified, nonsense mutations, frameshift mutations, missense changes, synonymous sequence variants and intronic changes. These findings prompted the identification of a new mutation in the human factor V gene, designated as Jaén-1, which is capable of altering the procoagulant function of factor V. In addition, an update is provided on the prospects for the treatment of factor V deficiency on the basis of yet-to-be-developed recombinant products or advanced gene and cell therapies that could potentially correct this hereditary disorder. 相似文献
993.
994.
Castro IU Stüber F Fabregat A Font J Fortuny A Bengoa C 《Journal of hazardous materials》2009,163(2-3):809-815
Supported Cu(II) polymer catalysts were used for the catalytic oxidation of phenol at 30 degrees C and atmospheric pressure using air and H(2)O(2) as oxidants. Heterogenisation of homogeneous Cu(II) catalysts was achieved by adsorption of Cu(II) salts onto polymeric matrices (poly(4-vinylpyridine), Chitosan). The catalytic active sites were represented by Cu(II) ions and showed to conserve their oxidative activity in heterogeneous catalysis as well as in homogeneous systems. The catalytic deactivation was evaluated by quantifying released Cu(II) ions in solution during oxidation, from where Cu-PVP(25) showed the best leaching levels no more than 5 mg L(-1). Results also indicated that Cu-PVP(25) had a catalytic activity (56% of phenol conversion when initial Cu(II) catalytic content was 200 mg L(Reaction)(-1)) comparable to that of commercial catalysts (59% of phenol conversion). Finally, the balance between activity and copper leaching was better represented by Cu-PVP(25) due to the heterogeneous catalytic activity had 86% performance in the heterogeneous phase, and the rest on the homogeneous phase, while Cu-PVP(2) had 59% and CuO/gamma-Al(2)O(3) 68%. 相似文献
995.
The increased growth of internet use in the last several years has opened up new possibilities for structural engineering analysis, moving from personal computer oriented software to client–server distributed software. In this paper two client–server applications for structural engineering based on stream sockets and on web services are presented. These two technologies have been chosen to compare, in terms of performance and complexity, new internet protocols with traditional ways of implementing client–server applications. Moreover, special care has been taken in the security aspects as the internet has become much more susceptible to breaches of security. Therefore, two new applications based on the same technologies have been created that guarantee a secure use of structural software. Also, two different client applications are presented to emphasize the versatility and power of internet distributed technology—one as a stand-alone application and the other as an integrated commercial computer-aided design program. 相似文献
996.
The balance between durability,reliability, and affordability in structural composites manufacturing
Fiber reinforced structural composites will play a key role in the development of the next generation of transportation vehicles (passenger cars, vans, light trucks, and heavy trucks) because of their high strength‐to‐weight and stiffness‐to‐weight ratio compared with metals. An integrated assessment of the durability, reliability, and affordability of these materials is critical to facilitate the inclusion of these materials into new designs. The result of this assessment should provide information to find the balance between the three performance measures. This paper describes a method to develop this assessment in the fabrication of sheet molding compound (SMC) parts, and discusses the concept of Preform Insert Assembly (PIA) for improved affordability in the manufacturing of composite parts. POLYM. COMPOS., 28:233–240, 2007. © 2007 Society of Plastics Engineers 相似文献
997.
Karem Arriaza Constanza Cuevas Eduardo Pena Patricia Siques Julio Brito 《International journal of molecular sciences》2022,23(13)
Hypobaric hypoxia is a condition that occurs at high altitudes (>2500 m) where the partial pressure of gases, particularly oxygen (PO2), decreases. This condition triggers several physiological and molecular responses. One of the principal responses is pulmonary vascular contraction, which seeks to optimize gas exchange under this condition, known as hypoxic pulmonary vasoconstriction (HPV); however, when this physiological response is exacerbated, it contributes to the development of high-altitude pulmonary hypertension (HAPH). Increased levels of zinc (Zn2+) and oxidative stress (known as the “ROS hypothesis”) have been demonstrated in the vasoconstriction process. Therefore, the aim of this review is to determine the relationship between molecular pathways associated with altered Zn2+ levels and oxidative stress in HPV in hypobaric hypoxic conditions. The results indicate an increased level of Zn2+, which is related to increasing mitochondrial ROS (mtROS), alterations in nitric oxide (NO), metallothionein (MT), zinc-regulated, iron-regulated transporter-like protein (ZIP), and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-induced protein kinase C epsilon (PKCε) activation in the development of HPV. In conclusion, there is an association between elevated Zn2+ levels and oxidative stress in HPV under different models of hypoxia, which contribute to understanding the molecular mechanism involved in HPV to prevent the development of HAPH. 相似文献
998.
A non-conserved sequence in the 5'region of the CYH2 intron from Saccharomyces cerevisiae controls splicing efficiency of the pre-mRNA 总被引:2,自引:0,他引:2
Ulrike Swida Eduardo Thüroff Edith Steindert Norbert F. Kufer 《Yeast (Chichester, England)》1988,4(3):209-217
The CYH2 gene from Saccharomyces cerevisiae containing one 510 bp intron is spliced inefficiently. We have shown previously that a non-conserved sequence within the intron is responsible for this low splicing efficiency. Using synthetic oligonucleotides comprising the identified region we show in this report that a very short region contains the specificity to act negatively on the splicing efficiency of the CYH2 gene. Furthermore, this sequence influences the splicing efficiency only when it is placed close to the 5' splice site of the gene. Investigations with chimeric CYH2/beta-actin genes show that this sequence acts independent from its natural surroundings. We propose that this sequence might interact with splicing factor(s). 相似文献
999.
The concentrations of individual and total glucosinolates were measured in four types of Portuguese cabbage and in one hybrid white cabbage before and after cooking. Typical Portuguese culinary procedures include boiling the cabbage for 10 min but for particular kale types the leaves are first shredded then boiled for 5 min (Caldo verde). Analysis of the fresh cabbage, cooked leaves and cooking water showed that the glucosinolate content of the cabbages is reduced by more than 50%. Almost all of this loss is accounted for as intact glucosinolates in the cooking water, normally used for soups in Portugal. 相似文献
1000.
Methicillin‐Resistant Staphylococcus aureus in Raw Meats and Prepared Foods in Public Hospitals in Salvador,Bahia, Brazil
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Wellington Luis Reis Costa Jeane dos Santos Ferreira Joelza Silva Carvalho Ellayne Souza Cerqueira Lucimara Cardoso Oliveira Rogeria Comastri de Castro Almeida 《Journal of food science》2015,80(1):M147-M150
This study investigated the presence of methicillin‐resistant Staphylococcus aureus (MRSA) in raw meat and fish and foods prepared from them for patient consumption in public hospitals in Salvador, Bahia, in northeastern Brazil. A total of 114 samples of raw meat and fish (chicken, n = 30; beef, n = 30; pork, n = 24; and fish, n = 30) and 63 samples of prepared foods (made with chicken, n = 15; beef, n = 15; pork, n = 15; and fish, n = 18) were collected from the kitchens of 10 different hospitals. Of the 114 investigated raw meat and fish samples, 28.1% were positive for MRSA, which comprised 23.3% beef, 23.3% chicken, 37.5% pork, and 30% fish samples. Of the prepared foods, 9.5% were positive for MRSA, which comprised 5.6% chicken products, 6.7% pork products, and 22.2% fish products. MRSA contamination was not detected in prepared beef dishes. A statistical analysis showed no association between the presence of MRSA and the type of raw food (P > 0.05). The high prevalence of MRSA among the raw foods tested and the presence of the microorganism in prepared foods emphasizes the necessity of enforcing hygienic practices within hospital kitchens. 相似文献