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Machine learning inspired workflow to revise field development plan under uncertainty
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作者 LOOMBA Ashish Kumar BOTECHIA Vinicius Eduardo SCHIOZER Denis José 《Petroleum Exploration and Development》 SCIE 2023年第6期1455-1465,共11页
We present an efficient and risk-informed closed-loop field development (CLFD) workflow for recurrently revising the field development plan (FDP) using the accrued information. To make the process practical, we integr... We present an efficient and risk-informed closed-loop field development (CLFD) workflow for recurrently revising the field development plan (FDP) using the accrued information. To make the process practical, we integrated multiple concepts of machine learning, an intelligent selection process to discard the worst FDP options and a growing set of representative reservoir models. These concepts were combined and used with a cluster-based learning and evolution optimizer to efficiently explore the search space of decision variables. Unlike previous studies, we also added the execution time of the CLFD workflow and worked with more realistic timelines to confirm the utility of a CLFD workflow. To appreciate the importance of data assimilation and new well-logs in a CLFD workflow, we carried out researches at rigorous conditions without a reduction in uncertainty attributes. The proposed CLFD workflow was implemented on a benchmark analogous to a giant field with extensively time-consuming simulation models. The results underscore that an ensemble with as few as 100 scenarios was sufficient to gauge the geological uncertainty, despite working with a giant field with highly heterogeneous characteristics. It is demonstrated that the CLFD workflow can improve the efficiency by over 85% compared to the previously validated workflow. Finally, we present some acute insights and problems related to data assimilation for the practical application of a CLFD workflow. 展开更多
关键词 field development plan closed-loop field development reservoir model machine learning reservoir uncertainty optimization reservoir simulation efficiency
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Respiratory muscle training with electronic devices in the postoperative period of hepatectomy:A randomized study
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作者 Marcelo Gustavo Pereira Aurea Maria Oliveira Silva +3 位作者 Fernanda Diório Masi Galhardo Beatriz Dellamutta Miranda Almeida Railaine Lais Lopes Ilka de Fatima Santana Ferreira Boin 《World Journal of Hepatology》 2023年第5期688-698,共11页
BACKGROUND Many studies have been developed with a focus on surgical techniques and drugs,but few that address the importance of rehabilitation in the pre and postoperative period,and the specific benefits for each su... BACKGROUND Many studies have been developed with a focus on surgical techniques and drugs,but few that address the importance of rehabilitation in the pre and postoperative period,and the specific benefits for each surgical procedure or type of neoplasm,aiming to minimize respiratory complications in the postoperative period.AIM To compare the strength of the respiratory muscles in the pre and postoperative periods of hepatectomy by laparotomy and to verify the incidence of postoperative pulmonary complications among the groups studied.METHODS Prospective,randomized,clinical trial study that compared the inspiratory muscle training group(GTMI)with the control group(CG).After the collection of sociodemographic and clinical data,in both groups,preoperatively,on the first and fifth postoperative days,vital signs and pulmonary mechanics were evaluated and recorded.Albumin and bilirubin values were recorded for the albumin-bilirubin(ALBI)score.After randomization and allocation of participants,those in the CG underwent conventional physical therapy and those in the GTMI underwent conventional physical therapy plus inspiratory muscle,in both groups for five postoperative days.RESULTS Of 76 subjects met eligibility criteria.The collection of 41 participants was completed:20 in the CG and 21 in the GTMI.The most frequent diagnosis was 41.5%with liver metastasis,followed by 26.8%with hepatocellular carcinoma.As for respiratory complications in the GTMI,there was no incidence.In the CG,there were three respiratory complications.Patients in the CG classified as ALBI score 3 presented,statistically,a higher energy value compared to patients classified as ALBI score 1 and 2(P=0.0187).Respiratory variables,measured preoperatively and on the first postoperative day,had a significant drop in both groups from the preoperative to the first postoperative day(P≤0.0001).When comparing the preoperative period and the fifth postoperative day between the GTMI and the CG,the maximal inspiratory pressure variable in the GTMI was statistically significant(P=0.0131).CONCLUSION All respiratory measures showed a reduction in the postoperative period.Respiratory muscle training using the Powerbreathe?device increased maximal inspiratory pressure and this may have contributed to a shorter hospital stay and better clinical outcome. 展开更多
关键词 POSTOPERATIVE shorter FIFTH
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Localized-states quantum confinement induced by roughness in CdMnTe/CdTe heterostructures grown on Si(111) substrates
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作者 Leonarde N.Rodrigues Wesley F.Inoch +3 位作者 Marcos L.F.Gomes Odilon D.D.Couto Jr. Bráulio S.Archanjo Sukarno O.Ferreira 《Journal of Semiconductors》 EI CAS CSCD 2024年第9期28-35,共8页
This work shows that despite a lattice mismatch of almost 20%, CdMnTe/CdTe/CdMnTe heterostructures grown directly on Si(111) have surprisingly good optical emission properties. The investigated structures were grown b... This work shows that despite a lattice mismatch of almost 20%, CdMnTe/CdTe/CdMnTe heterostructures grown directly on Si(111) have surprisingly good optical emission properties. The investigated structures were grown by molecular beam epitaxy and characterized by scanning transmission electron microscopy, macro-and micro-photoluminescence. Low temperature macro-photoluminescence experiments indicate three emission bands which depend on the CdTe layer thickness and have different confinement characteristics. Temperature measurements reveal that the lower energy emission band (at 1.48 eV)is associated to defects and bound exciton states, while the main emission at 1.61 eV has a weak 2D character and the higher energy one at 1.71 eV has a well-defined (zero-dimensional, 0D) 0D nature. Micro-photoluminescence measurements show the existence of sharp and strongly circularly polarized (up to 40%) emission lines which can be related to the presence of Mn in the heterostructure. This result opens the possibility of producing photon sources with the typical spin control of the diluted magnetic semiconductors using the low-cost silicon technology. 展开更多
关键词 CdMnTe/CdTe/CdMnTe heterostructure CdTe/CdMnTe quantum emitters quantum dot-like emission silicon(111)substrate
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The effectiveness of different wear indicators in quantifying wear on railway wheels of freight wagons
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作者 Philipe Augusto de Paula Pacheco M.Magelli +4 位作者 Matheus Valente Lopes Pedro Henrique Alves Correa N.Zampieri N.Bosso Auteliano Antunes dos Santos 《Railway Engineering Science》 EI 2024年第3期307-323,共17页
Railway infrastructure relies on the dynamic interaction between wheels and rails;thus,assessing wheel wear is a critical aspect of maintenance and safety.This paper focuses on the wheel-rail wear indicator T-gamma(T... Railway infrastructure relies on the dynamic interaction between wheels and rails;thus,assessing wheel wear is a critical aspect of maintenance and safety.This paper focuses on the wheel-rail wear indicator T-gamma(Tγ).Amidst its use,it becomes apparent that Tγ,while valuable,fails to provide a comprehensive reflection of the actual material removal and actual contact format,which means that using only Tγas a target for optimization of profiles is not ideal.In this work,three different freight wagons are evaluated:a meter-gauge and a broad-gauge heavy haul vehicles from South American railways,and a standard-gauge freight vehicle operated in Europe,with different axle loads and dissimilar new wheel/rail profiles.These vehicles are subjected to comprehensive multibody simulations on various tracks.The simulations aimed to elucidate the intricate relationship between different wear indicators:Tγ,wear index,material removal,and maximum wear depth,under diverse curves,non-compensated lateral accelerations(A_(nc)),and speeds.Some findings showed a correlation of 0.96 between Tγand wear depth and 0.82 between wear index and material removed for the outer wheel.From the results,the Tγis better than the wear index to be used when analyzing wear depth while the wear index is more suited to foresee the material lost.The results also show the low influence of A_(nc)on wear index and Tγ.By considering these factors together,the study aims to improve the understanding of wheel-rail wear by selecting the best wear analysis approaches based on the effectiveness of each parameter. 展开更多
关键词 Wear index Wear volume Wear modeling Dynamic simulation
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Role of the Wnt/β-catenin pathway in gastric cancer: An indepth literature review 被引量:63
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作者 Miguel Angel Chiurillo 《World Journal of Experimental Medicine》 2015年第2期84-102,共19页
Gastric cancer remains one of the most common cancers worldwide and one of the leading cause for cancerrelated deaths. Gastric adenocarcinoma is a multifactorial disease that is genetically, cytologically and architec... Gastric cancer remains one of the most common cancers worldwide and one of the leading cause for cancerrelated deaths. Gastric adenocarcinoma is a multifactorial disease that is genetically, cytologically and architecturally more heterogeneous than other gastrointestinal carcinomas.The aberrant activation of the Wnt/β-catenin signaling pathway is involved in the development and progression of a significant proportion of gastric cancer cases. This review focuses on the participation of the Wnt/b-catenin pathway in gastric cancer by offering an analysis of the relevant literature published in this field. Indeed, it is discussed the role of key factors in Wnt/β-catenin signaling and their downstream effectors regulating processes involved in tumor initiation, tumor growth, metastasis and resistance to therapy. Available data indicate that constitutive Wnt signalling resulting from Helicobacter pylori infection and inactivation of Wnt inhibitors(mainly by inactivating mutations and promoter hypermethylation) play an important role in gastric cancer. Moreover, a number of recent studies confirmed CTNNB1 and APC as driver genes in gastric cancer. The identification of specific membrane, intracellular, and extracellular components of the Wnt pathway has revealed potential targets for gastric cancer therapy. High-throughput "omics" approaches will help in the search for Wnt pathway antagonist in the near future. 展开更多
关键词 Gastric cancer Wnt β-catenin ONCOGENE Tumor SUPPRESSOR Epigenetics HELICOBACTER PYLORI Adenomatous POLYPOSIS coli
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Inflammatory bowel disease in an underdeveloped region of Northeastern Brazil 被引量:6
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作者 José Miguel Luz Parente Claudio Saddy Rodrigues Coy +5 位作者 Viriato Campelo Mírian Perpétua Palha Dias Parente Leonardo Araújo Costa Renata Mendes da Silva Celso Stephan José Murilo Robilotta Zeitune 《World Journal of Gastroenterology》 SCIE CAS 2015年第4期1197-1206,共10页
AIM: To evaluate the demographic characteristics and clinical phenotypes of inflammatory bowel disease(IBD) in a geographic area in Northeastern Brazil.METHODS: This retrospective study was conducted at the Hospital o... AIM: To evaluate the demographic characteristics and clinical phenotypes of inflammatory bowel disease(IBD) in a geographic area in Northeastern Brazil.METHODS: This retrospective study was conducted at the Hospital of the Federal University of Piauí in Northeastern Brazil. Demographic characteristics and clinical phenotypes of IBD were analyzed in relation to the time of diagnostic confirmation, which was defined as the date of disease onset. Data were collected between January 2011 and December 2012 and included all census patients 18 years of age or older during that period for whom there was diagnostic confirmation of Crohn's disease(CD), ulcerative colitis(UC), or unclassified colitis according to the Montreal criteria. We also analyzed the period of time between the onset of clinical manifestations and the diagnosis of IBD(delay in the diagnosis). Statistical analyses included means and standard deviations for numeric variables and the Pearson χ2 adherence test for nominal variables. The annual index occurrence and overall prevalence of IBD at our institution were also calculated, with P values < 0.05 indicating statistical significance. This study was approved by the Institutional Ethics and Research Committee.RESULTS: A total of 252 patients with IBD were included, including 152(60.3%) UC patients and 100(39.7%) CD patients. The clinical and demographic characteristics of all patients with IBD showed a female to male ratio of 1.3:1.0 and a mean age of35.2(SD = 14.5) years. In addition, the majority of patients were miscegenated(171, 67.9%), had received higher education(157, 62.4%), lived in urban areas(217, 86.1%), and were under the age of 40 years(97, 62.5%). For patients with CD, according to the Montreal classification, the predominant features present from the onset of disease were an age between 17 and 40 years(A2); colonic disease location(L2); and nonstricturing, nonfistulizing disease behavior(B1). However, approximately one-quarter of all CD patients demonstrated perineal involvement. We also observed considerable delay in the diagnosis of IBD throughout the entire study period(mean = 35.5 mo). In addition, the annual index occurrence rose from 0.08 to 1.53 cases/105 inhabitants/year during the study period, and the prevalence rate was 12.8 cases/105 inhabitants in 2012. Over the last two decades, there was a noted increase in the frequency of IBD in the study area.CONCLUSION: In this study, there was a predominance of patients with UC, young people under 40 years of age, individuals with racial miscegenation, and low annual incomes. 展开更多
关键词 INFLAMMATORY BOWEL DISEASES Crohn’s DISEASE Ulcera
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Emphysematous Complications Following Third Molars Removal: Incidence among 10779 Surgeries and Report of Two Cases 被引量:3
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作者 Leandro E. Klüppel Fernando Antonini +2 位作者 Alessandro Costa da Silva Márcio de Moraes Saulo Ellery Santos 《Open Journal of Stomatology》 2014年第7期352-357,共6页
Subcutaneous emphysema is a condition that results from introduction of air into soft tissues. In head and neck, it is commonly observed following fractures of paranasal sinuses. Less frequently, it may occur during s... Subcutaneous emphysema is a condition that results from introduction of air into soft tissues. In head and neck, it is commonly observed following fractures of paranasal sinuses. Less frequently, it may occur during surgical procedures for tooth removal, when air from dental hand-pieces is forced into surgical site. Depending on its extension, it may involve vital spaces such as mediastinum. This specific finding may induce life-threatening situations. The aim of this article is to establish the incidence of subcutaneous emphysema among 10,779 impacted third molar surgical procedures and report the cases in which such complications had occurred. In this retrospective study, data collected from 10,779 third molar extraction procedures performed at Piracicaba School of Dentistry were evaluated for the occurrence of subcutaneous emphysema. Two cases of subcutaneous emphysema (0.018%) occurred following extraction of impacted third molars. Both were associated with mandibular tooth and related to the use of dental air hand-piece. One of the cases involved submandibular and buccal spaces while the other involved buccal and canine spaces. Regression of emphysema occurred spontaneously and postoperative recovery was uneventful. Subcutaneous emphysema following impacted third molar extractions is rare and strongly associated with the use of air turbines. Follow-up and preservation are the treatments of choice, but clinicians should be aware about the possibility of microbial spreading through facial spaces. 展开更多
关键词 SUBCUTANEOUS EMPHYSEMA IMPACTED TOOTH Air Hand-Piece
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Anti-inflammatory intestinal activity of Combretum duarteanum Cambess. in trinitrobenzene sulfonic acid colitis model 被引量:2
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作者 Gedson Rodrigues de Morais Lima Flavia Danniele Frota MachadoLarissa Lucena Périco +7 位作者 Felipe Meira de Faria Anderson Luiz-Ferreira Alba Regina Monteiro Souza Brito Cláudia Helena Pellizzon Clélia Akiko Hiruma-Lima Josean Fechine Tavares JoséMaria Barbosa Filho LeOnia Maria Batista 《World Journal of Gastroenterology》 SCIE CAS 2017年第8期1353-1366,共14页
To evaluate the anti-inflammatory intestinal effect of the ethanolic extract (EtOHE) and hexane phase (HexP) obtained from the leaves of Combretum duarteanum (Cd).METHODSInflammatory bowel disease was induced using tr... To evaluate the anti-inflammatory intestinal effect of the ethanolic extract (EtOHE) and hexane phase (HexP) obtained from the leaves of Combretum duarteanum (Cd).METHODSInflammatory bowel disease was induced using trinitrobenzenesulfonic acid in acute and relapsed ulcerative colitis in rat models. Damage scores, and biochemical, histological and immunohistochemical parameters were evaluated.RESULTSBoth Cd-EtOHE and Cd-HexP caused significant reductions in macroscopic lesion scores and ulcerative lesion areas. The vegetable samples inhibited myeloperoxidase increase, as well as pro-inflammatory cytokines TNF-α and IL-1β. Anti-inflammatory cytokine IL-10 also increased in animals treated with the tested plant samples. The anti-inflammatory intestinal effect is related to decreased expression of cyclooxygenase-2, proliferating cell nuclear antigen, and an increase in superoxide dismutase.CONCLUSIONThe data indicate anti-inflammatory intestinal activity. The effects may also involve participation of the antioxidant system and principal cytokines relating to inflammatory bowel disease. 展开更多
关键词 Combretum duarteanum Medicinal plants COMBRETACEAE Inflammatory bowel disease Anti-inflammatory intestinal activity
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Methods and parameters of melting curve analysis for identification of Leishmania species:A scoping review 被引量:1
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作者 Juliana J G Ferreira Fernanda S Nascimento +2 位作者 Glaucia E B Marcon Eros A de Almeida Sandra C B Costa 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2021年第12期528-542,共15页
Leishmaniasis is a set of diseases with a worldwide distribution that affects mainly economically underprivileged populations in developing countries. It has a major impact on public health, with a global cost of bill... Leishmaniasis is a set of diseases with a worldwide distribution that affects mainly economically underprivileged populations in developing countries. It has a major impact on public health, with a global cost of billions of dollars per year. The treatment and control of leishmaniasis vary according to the Leishmania species involved, which require reliable methods for species identification. Since most of the currently used methods have limitations, there is a need for assays that allow rapid, precise identification of the offending species. Real-time polymerase chain reactions in conjunction with dissociation curve analysis have been used to detect differences in the DNA composition of selected genes of Leishmania spp. Kinetoplast DNA is the main molecular target used because of its high copy number per parasite, but other targets have also been studied. As part of an effort to establish melting temperature standards for each target gene, we have reviewed the pertinent literature available in public databases, including Pub Med, Web of Science, Sci ELO and LILACS, using the keywords "Leishmania", "leishmaniasis", "realtime PCR", "melting temperature", and "melting curve", alone or in combination. After applying eligibility criteria, 27 articles were selected for analysis. A considerable variation in the methodologies analyzed was found regarding molecular targets, standardization of the methods, reproducibility and specificity. Because of this, statistical analysis was not performed. In most cases, the methods were able to differentiate the parasite at the subgenus level or few species regardless of the target chosen. 展开更多
关键词 LEISHMANIASIS Melting temperature Real-time PCR
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The VILMA intelligent vehicle:an architectural design for cooperative control between driver and automated system 被引量:2
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作者 Olmer Garcia Giovani Bernardes Vitor +2 位作者 Janito Vaqueiro Ferreira Pablo Siqueira Meirelles Arthurde Miranda Neto 《Journal of Modern Transportation》 2018年第3期220-229,共10页
Intelligent autonomous vehicles have received a great degree of attention in recent years. Although the technology required for these vehicles is relatively advanced, the challenge is firstly to ensure that drivers ca... Intelligent autonomous vehicles have received a great degree of attention in recent years. Although the technology required for these vehicles is relatively advanced, the challenge is firstly to ensure that drivers can understand the capabilities and limitations of such systems and secondly to design a system that can handle the interaction between the driver and the automated intelligent system. In this study, we describe an approach using different strategies for an autonomous system and a driver to drive a vehicle cooperatively. The proposed strategies are referred to as cooperative planning and control and determine when and how the path projected by the autonomous system can be changed safely by the driver to a path that he wishes to follow. The first phase of the project is described, covering the design and implementation of an autonomous test vehicle. Experiments are carried out with a driver to test the cooperative planning and control concepts proposed here. 展开更多
关键词 Autonomous vehicles Embedded systems Cooperative systems Visual servoing
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A Model of Cellular Automata for the Fuzzy Control of Aphids 被引量:1
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作者 Magda da Silva Peixoto Laécio Carvalho de Barros Rodney Carlos Bassanezi 《Applied Mathematics》 2014年第8期1133-1141,共9页
Pesticides are substances used to prevent, destroy or mitigate any pest. We have adopted in this paper the Cellular Automata model to study the dispersion of the aphids in the block of citric trees using the pesticide... Pesticides are substances used to prevent, destroy or mitigate any pest. We have adopted in this paper the Cellular Automata model to study the dispersion of the aphids in the block of citric trees using the pesticides (chemical control) and the biological agent (biological control). The main purpose of this research is the development of a simple and specific methodology to study Citrus Sudden Death (CSD). CSD is a disease that has affected sweet orange trees grafted on Rangpur lime in the state of S?o Paulo-Brazil. Some studies suggest that this disease has been caused by a virus and it is transmitted by insects known as aphids (vector). The ladybug was selected among the most known enemies of aphids in citrus in Brazil. In order to elaborate a predator-prey type of model to study the interaction between aphids (preys) and ladybugs (predators) in citriculture we have used a fuzzy rule-based system (FRBS). The states of the variables of the system (inputs) are the density of preys and the density of predators and their variations are the outputs. Therefore we take into account the effect of the wind in the space covered by the aphid, since the wind is important for the flight of the aphid as described in Peixoto et al. (2008) [1]. After, we used a FRBS to establish the relationship between the quantity of pesticides and the density of the preys. The simulations have been performed and have been compared between blocks with the presence of both aphids and ladybugs without the use of pesticides and the presence of them with the use of these ones using the Cellular Automata model. Numerical simulations allow us to foresee the behavior of the system, hence creating a spectrum of possibilities and proposing control techniques for different initial scenarios. 展开更多
关键词 Fuzzy Sets Fuzzy Rule Base Cellular Automata Simulations PESTICIDES
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Modelling Animal Activity as Curves: An Approach Using Wavelet-Based Functional Data Analysis
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作者 Barbara Henning Airton Kist +4 位作者 Alusio Pinheiro Rafael L. Camargo Thiago M. Batista Everardo M. Carneiro Sérgio F. dos Reis 《Open Journal of Statistics》 2017年第2期203-215,共13页
Temporal activity patterns in animals emerge from complex interactions between choices made by organisms as responses to biotic interactions and challenges posed by external factors. Temporal activity pattern is an in... Temporal activity patterns in animals emerge from complex interactions between choices made by organisms as responses to biotic interactions and challenges posed by external factors. Temporal activity pattern is an inherently continuous process, even being recorded as a time series. The discreteness of the data set is clearly due to data-acquisition limitations rather than a true underlying discrete nature of the phenomenon itself. Therefore, curves are a natural representation for high-frequency data. Here, we fully model temporal activity data as curves integrating wavelets and functional data analysis, allowing for testing hypotheses based on curves rather than on scalar and vector-valued data. Temporal activity data were obtained experimentally for males and females of a small-bodied marsupial and modelled as wavelets with independent and identically distributed errors and dependent errors. The null hypothesis of no difference in temporal activity pattern between male and female curves was tested with functional analysis of variance (FANOVA). The null hypothesis was rejected by FANOVA and we discussed the differences in temporal activity pattern curves between males and females in terms of ecological and life-history attributes of the reference species. We also performed numerical analysis that shed light on the regularity properties of the wavelet bases used and the thresholding parameters. 展开更多
关键词 Functional Analysis of Variance HIGH-FREQUENCY Data TEMPORAL Activity Pattern SHRINKAGE WAVELET THRESHOLDING
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An Alternative Three-phase Transmission Lines Model in Phase Domain
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作者 C. G. Carvalho S. Kurokawa J. Pissolato 《Energy and Power Engineering》 2013年第4期1490-1496,共7页
The objective of this paper is to show an alternative model of a non-transposed three-phase transmission line with a vertical symmetry plane in phase domain. Due the line physical characteristics, it can be represente... The objective of this paper is to show an alternative model of a non-transposed three-phase transmission line with a vertical symmetry plane in phase domain. Due the line physical characteristics, it can be represented by a system consisting of a single?phase and a two-phase line. In this system, the equations describing the behavior of the values in single-phase line terminals are known, while the equations for two-phase line to be obtained. Using a transformation matrix written explicitly according to three-phase line parameters, it is possible to obtain the currents and voltages in phase domain of two-phase line. Then, modal values of three-phase line are converted into phase domain and thus obtain the analytical model for this line. To verify the performance of this model, it was used to simulate the energization of a 440 kV three-phase line and the results were compared to results obtained using a classical model. 展开更多
关键词 Transmission Lines Frequency DEPENDENCE MODAL Representation Transformation Matrix NEWTON-RAPHSON PHASE DOMAIN
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Thermochemical Parameters of Tetramethylthiourea Adducts of Certain Metal(II) Bromides
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作者 Pedro Oliver Dunstan 《Open Journal of Physical Chemistry》 2015年第1期9-19,共11页
Complexes of the general formula [MBr2(TMTU)n] (where M is Mn, Fe, Co, Ni, Cu, Zn or Cd;TMTU is Tetramethylthiourea;n is 0.75, 2 or 3) were obtained by the reaction of salts and ligand in solution. The bromides were s... Complexes of the general formula [MBr2(TMTU)n] (where M is Mn, Fe, Co, Ni, Cu, Zn or Cd;TMTU is Tetramethylthiourea;n is 0.75, 2 or 3) were obtained by the reaction of salts and ligand in solution. The bromides were selected among several other salts because they had thermochemical data in the literature. Properties as capillary melting points;C, H, N, Br and metal contents;TG/DTG and DSC curves;and IR and electronic spectra were determined. The values of several thermodynamic parameters for the complexes were found by solution calorimetry. From them, the standard enthalpies of the metal-sulphur coordinated bonds were calculated. The standard enthalpies of the formation of the gaseous phase adducts also were estimated. 展开更多
关键词 ENTHALPIES of Formation Thermodynamic Coordinated Bond ENTHALPIES Solution CALORIMETRY Dissolution ENTHALPIES Tetramethylthiourea ADDUCTS
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Thermochemical Parameters of 3-Chloroaniline Complexes of Certain Bivalent Transition Metal Bromides
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作者 Pedro Oliver Dunstan Abdul Majeed Khan 《Open Journal of Physical Chemistry》 2013年第4期163-169,共7页
Complexes of general formula [MBr2(3-clan)n] (where M is Fe, Ni, Cu or Zn;3-clan = m-chloroaniline;n is 1.5 or 2) were prepared and their characteristic properties, such as capillary MP;C, H, N, Br and metal contents;... Complexes of general formula [MBr2(3-clan)n] (where M is Fe, Ni, Cu or Zn;3-clan = m-chloroaniline;n is 1.5 or 2) were prepared and their characteristic properties, such as capillary MP;C, H, N, Br and metal contents;TG/DTG and DSC curves;and IR and electronic spectra were determined. By calorimetric measurements in solution, the values of some thermodynamic parameters of the complexes were determined. From these values, the standard enthalpies of the metal-nitrogen coordinated bonds were calculated, and the standard enthalpies of the formation of the gaseous phase complexes were estimated. 展开更多
关键词 ENTHALPIES of Formation Thermodynamic Coordinated Bond ENTHALPIES Calorimetric Measurements
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Development of a Soy-Based Synbiotic Beverage
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作者 Suzana Reis Evangelista Gislaine Ghiselli Francisco Maugeri Filho 《Food and Nutrition Sciences》 2012年第8期1128-1135,共8页
Nowadays consumers seek foods that not only provide basic nutrition but also contain compounds that contribute to health. Thus, different products have been designed to meet this demand, especially those with probioti... Nowadays consumers seek foods that not only provide basic nutrition but also contain compounds that contribute to health. Thus, different products have been designed to meet this demand, especially those with probiotic and prebiotic characteristics. This study aimed to evaluate different formulations of a soy-based synbiotic beverage. The composition and process conditions were defined using a Placket & Burman factorial design in which the independent variables were process temperature, concentrations of the soy hydrosoluble extract and fructooligosaccharides (FOS) and the initial concentration of the probiotics Bifidobaterium longum, Lactobacillus acidophilus, Lactobacillus paracasei subsp. Paracasei, Lactobacillus rhamnosus. Changes to the product by addition of sucrose, Streptococcus thermophilus and Lactobacillus delbrueckii subsp. Bulgaricus were also studied. Response parameters were: pH, cell concentration (plate counting), and quantification of fructooligosaccharides, acetic acid and lactic acid. The specific growth rate (μx) and change in cell count (Δx) were determined in each formulation. The soybean hydrosoluble extract was considered a good substrate for beverage production;FOS had a greater effect at lower concentrations. At the end of all fermentation tests the total probiotic count was greater than 7 log CFU/mL, meeting the legal requirements of a functional food. Lower temperatures were better for the growth of probiotics. The addition of sucrose resulted in a lower consumption of FOS by the fermenting microorganisms, while the presence of Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus represented little change concerning the evaluated characteristics. Therefore, according to the results of this study, the production of a soy-based symbiotic fermented beverage can be performed using soybean hydrosoluble extract at 10% (w/v), fructooligosaccharides at about 3% (w/v), sucrose at 12% (w/v), and the process temperature should be maintained at 35℃. Initial probiotic concentrations need not exceed 5 × 106 CFU/ml. 展开更多
关键词 PROBIOTICS PREBIOTICS SOY SYNBIOTIC BEVERAGE Functional FOOD
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Orlistat-lnduced Modulation of Plasma Metabolites Independent of Weight Loss in Overweight Females
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作者 Thiago I. B. Lopes Lucas G. Martins +2 位作者 Sabrina Nagassaki Bruno Geloneze Anita Jocelyne Marsaioli 《Journal of Chemistry and Chemical Engineering》 2013年第6期547-555,共9页
Orlistat-induced weight loss results in amelioration in several comorbidities including obesity-related dyslipidemia. The aim of the present study was to characterize the changes in the blood plasma metabolic profile ... Orlistat-induced weight loss results in amelioration in several comorbidities including obesity-related dyslipidemia. The aim of the present study was to characterize the changes in the blood plasma metabolic profile from overweight women treated with Orlistat, a lipase inhibitor. A metabonomic approach employing LHNMR was applied to the access metabolic profile in lean and overweight women after a 120 day treatment with 120 mg of Orlistat three times daily. Twenty overweight women (BMI: 32.8 ± 2.9 kg/m2) were evaluated before and after Orlistat treatment and seven normal weight women (BMh 21.8 ± 1.4 kg/m2) were taken as control. After 120 days of treatment with Orlistat, no significant weight changes were observed. However, Orlistat-induced metabolic changes in overweight subjects decreased the profile differences between lean and obese individuals, independent of weight loss. These were associated to decreasing levels of lactate and calcium. Higher levels of lactate, alanine and lipids from overweight subjects were detected in comparison to lean individuals. These results show that a lipase inhibitor shifts the metabolic profile of overweight subjects towards normality, independent of weight loss. 展开更多
关键词 tH NMR METABONOMICS LACTATE EDTA calcium.
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Turbo and LDPC Codes Defined over a Ring Z4 Applied to OFDM Systems
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作者 Maria Leopoldina Martins Neves Seixas Goncalves Renata Mataveli Viti Renato Baldini Filho 《通讯和计算机(中英文版)》 2011年第11期971-977,共7页
关键词 正交频分复用系统 涡轮码 定义 频率选择性衰落信道 DM 高斯白噪声 绩效评估 性能评价
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Demographic Expansion and Contraction in a Neotropical Fish during the Late Pleistocene-Holocene
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作者 Carolina L. N. Costa S. Ivan Perez +4 位作者 José Louvise Carlos H. Tonhatti Rute B. G. Clemente-Carvalho Ana C. Petry S. F. dos Reis 《Open Journal of Statistics》 2019年第4期470-483,共14页
Demographic changes during the late Pleistocene-Holocene left signatures in the DNA of contemporary populations. These signatures reveal demographic phenomena like the increase or decrease in effective population size... Demographic changes during the late Pleistocene-Holocene left signatures in the DNA of contemporary populations. These signatures reveal demographic phenomena like the increase or decrease in effective population size. In this paper we searched for signatures of demographic change in the DNA of the Neotropical freshwater fish Poecilia vivipara. Also, we investigated whether demographic changes are correlated with palaeoclimatic events of the late Pleistocene-Holocene, in particular, if changes in effective population size are correlated with expansion and contraction of available habitats, induced by global ice-volume changes and sea-level fluctuations. We used Bayesian Skyline Plot (BSP) analysis with sequences from the mitochondrial gene cytochrome b to estimate the ancestral demography of the Neotropical freshwater fish P. vivipara. To test the assumptions of neutrality and absence of population structure we used Tajima’s D and Spatial Analysis of Molecular Variance (SAMOVA), respectively. Effective population size of P. vivipara remained stable until 75,000 years ago, increased by 10-fold reaching a maximum at approximately 25,000 years ago, then suddenly declined at the Pleistocene-Holocene boundary. Variation in effective population size in P. vivipara correlates with expansion and contraction of habitats induced by sea-level fluctuations, caused by the advance and retreat of ice sheets during the Last Glacial Maximum (LGM). 展开更多
关键词 Ancestral Population Dynamics COALESCENCE Bayesian SKYLINE PLOT Mitochondrial DNA Last GLACIAL Maximum
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Biosurfactant Production by Pseudomonas aeruginosa and Yarrowia lipolytica and Its Use for Detergent Formulations
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作者 Silvanito Alves Barbosa Diego de Freitas Coelho +2 位作者 Edgar Silveira Elias Basile Tambourgi Roberto Rodrigues de Souza 《Journal of Chemistry and Chemical Engineering》 2013年第8期767-773,共7页
This work reports detergents production using biological surfactants, microbiologically synthesized, and compares its foaming power and emulsification capacity to those presented by a petroleum based surfactant. Both ... This work reports detergents production using biological surfactants, microbiologically synthesized, and compares its foaming power and emulsification capacity to those presented by a petroleum based surfactant. Both used microorganisms were capable to produce surfactants, been able to emulsify oil/water mixtures and cause decrease of surface tension of water. The biosurfactant produced from Yarrowia lipolytica has a critical micelle concentration lower than that obtained from Pseudomonas aeruginosa (10 and 30 mg·Lt, respectively), but the later showed better results in foaming power and emulsification experiments, similar to the synthetic detergent. 展开更多
关键词 Biodetergent BIOSURFACTANT Pseudomonas aeruginosa Yarrowia lipolytica.
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