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Iron toxicity resistance strategies in tropical grasses:The role of apoplastic radicular barriers

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Journal of Environmental Sciences 2019年第4期31卷 257-266页

作者： Advanio Inacio Siqueira-silva Camilla oliveira Rios Eduardo Gusmao Pereira Institute of Biological and Health Sciences Federal University of Vicosa (UFV)Campus Florestal Minas Gerais Brazil Federal University of Western Para (UFoPA) University Campus of JurutiPara Brazil Postgradute Program in Management and Conservation of Natural and Agrarian Ecosystems UFV Campus Florestal Florestal Minas Gerais Brazil

The revegetation of mined areas poses a great challenge to the iron ore mining *** initial recovery process in degraded areas might rely on the use of Fe-resistant *** grasses, such as Paspalum densum and Echinochloa crus-galli, show different resistance strategies to iron toxicity; however, these mechanisms are poorly *** Fe-resistance mechanisms and direct iron toxicity as a function of root apex removal were investigated. To achieve this purpose, both grass species were grown for up to 480 hr in a nutrient solution containing 0.019 or 7 mmol/L Fe-EDTA after the root apices had been removed or maintained. Cultivation in the presence of excess iron-induced leaf bronzing and the formation of iron plaque on the root surfaces of both grass species, but was more significant on those plants whose root apex had been removed. Iron accumulation was higher in the roots, but reached phytotoxic levels in the aerial parts as well. It did not hinder the biosynthesis of chloroplastidic pigments. No significant changes in gas exchange and chlorophyll a fluorescence occurred in either grass when their roots were kept intact; the contrary was true for plants with excised root apices. In both studied grasses, the root apoplastic barriers had an important function in the restriction of iron translocation from the root to the aerial plant parts, especially in E. crus-galli. Root apex removal negatively influenced the iron toxicity resistance mechanisms(tolerance in P. densum and avoidance in E. crus-galli).

关键词： Paspalum densum Echinochloa crus-galli Apoplastic barrier Iron toxicity

EVoLUTIoN oF THE BENEFICIAL oWNERSHIP CoNCEPT： MoRE THAN HALF oF CENTURY oF UNCERTAINTY AND WHAT HISToRY CAN TELL US

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Frontiers of Law in China-Selected Publications from Chinese Universities 2017年第4期12卷 501-523页

作者： Bruno da silva Ph.D. in International Tax Law Faculty of Law University of Amsterdam Amsterdam

The beneficial ownership concept has constituted for more than half a century one of the most fundamental and debated issues in the application of tax treaties. This article goes back to routes of this term explaining the reason of its original inclusion in the oECD Model Tax Convention and why ultimately such inclusion may have not been necessary. Then it analyses the historical developments of beneficial ownership in the oECD Model Tax Convention. For that purpose it considers different interpretations adopted by jurisdictions （particularly in China） and local courts delving into some of the landmark cases on the subject. Finally it provides a detailed analysis of the current meaning of beneficial ownership considering the most recent developments in the Commentary to the oECD Model Tax Convention.

关键词： beneficial ownership oECD Model Tax Convention Commentary,interpretation case-law China

Heterologous expression,chaperone mediated solubilization and purification of parasitic nematode-specific growth factor-like protein of Setaria digitata

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Asian Pacific Journal of Tropical Medicine 2014年第2期7卷 85-92页

作者： W.WP.Rodrigo R.S Dassanayake E.H.Karunanayake Y.I.N.silva Gunawardene o.VDS.J.Weerasena Department of Chemistry Faculty of ScienceUniversity of Colombo90Cumaratunga Munidasa Mawatha.Colombo 03Sri Lanka Institute of Biochemistry Molecular Biology and BiotechnologyUniversity of Colombo90Cumaratunga Munidasa MawathaColombo 03Sri Lanka Molecular Medicine Unit Faculty of MedicineUniversity of Kelaniya

objective:To clone,express and purify a putative parasitic nematode specific protein of Setaria digitata(***),filarial nematode that infects livestock and cause significant economic losses in Far East and Asia to he used for structural and functional ***:To characterize uneharacterized gene of,***(SDUG),the herterologous expression of SDUG was carried out in the pET[cloned into pET45b(+)]expression system initially and co-expression of SDUC using chaperoiie plasmids pG-KJE8,pGro 7,pKJE7,pG-Tf2 and pTf16 containing chapcrone proteins of dnaK-dnaJ-grpE-groES-gro-E,groES-groEL,dnaK-dnaJ-grpE,groES-groEL-tig,and tig respectively,was carried out ***:Expression of SDUG was seen when Escherichia coli strain BI.21(DE3)is used,while concentrating protein largely into the insoluble *** co-expression of SDUG using chaperoiie plasmid mediated system indicated a significant increase of the protein in the soluble *** the chaperon plasniid sets,the highest amount of recombinant SDUP in the soluble fraction was seen when pGro7 was used in the presence of2 mg/mL L-arabinosc and 0.6M IPTG concentration in the culture medium and for 3 h of incubation at the temperature of 28℃.Recombinant SDUG was purified both from soluble and insoluble fractions using Ni affinity ***-PAGE and western blot analyses of these proteins revealed a single band having expected size of^24 ***:SDUG seems to be more aggregate-prone and hydrophobic in nature and such protein can make soluble by correct selecting the inducer concentrations and induction temperature and its duration.

关键词： Setaria digitata Uncharacterized gene Chaperon Co-expression

Stable two-sided matching of slot allocation in airport collaborative decision making by top trading cycles mechanism

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Chinese Journal of Aeronautics 2018年第3期31卷 534-545页

作者： Marcio Augusto DA silva SoUZA Weigang LI Reinaldo Crispiniano GARCIA Trans Lab Department of Computer Science University of Brasilia Department of Production Engineering University of Brasilia

The problem of capacity shortage in some airports needs to be dealt with sustainable solutions including a more efficient use of the existing runway slots at the airports. The Collaborative Decision Making（CDM） is an important approach applied to Air Traffic Management（ATM）to achieve this efficient use of the slots allocation. Using the Matching approach for two-sided markets of Game theory, the Top Trading Cycle CDM（TTC-CDM） algorithm developed in this research is an extension of the CDM approach aggregating the Ground Delay Program（GDP）of the air sector. The paper compared the developed TTC-CDM model to the existing models such as the conventional Compression algorithm in CDM, the Trade Cycle algorithm and the Deferred Acceptance CDM（DA-CDM） model to evaluate the performance of the proposed model. Through a case study, the results show the effective application of TTC-CDM model to slot allocation in ATM and also presents the advantage of considering the preferences of airport managers beside ATC controllers and airlines in the decision processing.

关键词： Air traffic management Collaborative decision making Deferred acceptance Game theory Top trading cycles

Conscience imperative of providing information and knowledge in hepatology:The Portuguese approach

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World Journal of Clinical Cases 2017年第1期5卷 24-26页

作者： Guilherme Macedo Marco.silva Department of Gastroenterology the Centro Hospitalar São JoãoWGO Training CenterFaculty of MedicineUniversity of Porto4200-319 PortoPortugal

The last 25 years have been a thrilling time for the Portuguese hepatologists. our national meetings have been providing the forum for the exchange of scientific ideas and the presentation of clinical research in clinical Hepatology, a growing world of knowledge in medical care. Bridging the gaps between technology and clinical daily practice, the latest development and the almost humble bedside care, has been a challenge for the increasing numbers of doctors devoted to the diagnostic and treatment of liver disease. We have been trying to be very persuasive among the Portuguese medical community in demonstrating that cultural vectors may influence the origin and pattern of liver disease among us. Viral hepatitis and alcoholic liver disease are paradigms of this assumption. Chronic liver disease is responsible for 3% of the deaths in Portugal, which accounts for the top ten causes of death in our country. The recognition by public health authorities of this fact along with the national net of hepatology outpatient consultation in public hospitals, has brought liver diseases under the lights of doctors concerns and an increased public awareness of its dimension.

关键词： Alcohol Cirrhosis Hepatology Liver Public health

Microstructural Morphologies and Experimental Growth Laws during Solidification of Monotectic and Hypermonotectic Al-Pb Alloys

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Journal of Materials Science & Technology 2014年第4期30卷 401-407页

作者： Adrina P.silva Amauri Garcia José E.Spinelli Department of Materials Engineering University of Campinas-UNICAMP Department of Materials Engineering Federal University of Sao Carlos-UFSCar

AI-Pb alloys with monotectic and hypermonotectic compositions were directionally solidified under unsteady- state heat flow conditions. The cooling curves recorded during solidification allowed solidification thermal parameters such as the cooling rate （T）, growth rate （v） and thermal gradient （G） to be experimentally determined. Different microstructural patterns have been associated with the alloy solute content, i.e., AI-1.2 and 2.1 wt% Pb. A sequence of morphologies from the bottom to the top of the A1-1.2 wt% Pb alloy casting （monotectic） can be observed： Pb-rich droplets in the aluminum-rich matrix, followed by a region of microstructural transition formed by droplets and fibers and finally by a mixture of fibers and strings of pearls. A completely fibrous structure （without transition） has been observed along the entire AI-2.1 wt% Pb alloy casting （hypermonotectic）. The interphase spacing （λ） was measured along the casting length, and experimental correlations between λand experimental solidification thermal parameters have been established. Power laws with a -2.2 exponent expressing λ as a function of the growth rate, v, were found to better represent the fibrous growth of both AI-Pb alloys. Moreover, a single experimental law expressing λ as a function of both G and v was found to describe the fibrous growth of both the monotectic and the hypermonotectic alloys experimentally examined.

关键词： Aluminum alloys Casting Phase transformation

Probability Enhanced Entropy(PEE) Novel Feature for Improved Bird Sound Classification

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Machine Intelligence Research 2022年第1期19卷 52-62页

作者： Ramashini Murugaiya Pg Emeroylariffion Abas Liyanage Chandratilak De silva faculty of Integrated Technologies Universiti Brunei DarussalamBandar Seri Begawan BE1410Brunei Darussalam Department of Computer Science and Informatics Uva Wellassa UniversityBadulla 90000Sri Lanka

Identification of bird species from their sounds has become an important area in biodiversity-related research due to the relative ease of capturing bird sounds in the commonly challenging habitat. Audio features have a massive impact on the classification task since they are the fundamental elements used to differentiate classes. As such, the extraction of informative properties of the data is a crucial stage of any classification-based application. Therefore, it is vital to identify the most significant feature to represent the actual bird sounds. In this paper, we propose a novel feature that can advance classification accuracy with modified features, which are most suitable for classifying birds from its audio sounds. Modified Gammatone frequency cepstral coefficient(GTCC) features have been extracted with their frequency banks adjusted to suit bird sounds. The features are then used to train and test a support vector machine(SVM) classifier. It has been shown that the modified GTCC features are able to give 86% accuracy with twenty Bornean birds. Furthermore, in this paper, we are proposing a novel probability enhanced entropy(PEE) feature, which, when combined with the modified GTCC features, is able to improve accuracy further to 89.5%. These results are significant as the relatively low-resource intensive SVM with the proposed modified GTCC, and the proposed novel PEE feature can be implemented in a real-time system to assist researchers,scientists, conservationists, and even eco-tourists in identifying bird species in the dense forest.

关键词： Bird sounds classification Gammatone frequency cepstral coefficient(GTCC) probability enhanced entropy(PEE) support vector machine(SVM)

Laser texturing of piston ring for tribological performance improvement

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Friction 2023年第10期11卷 1895-1905页

作者： Rita FERREIRA Óscar CARVALHo Luís SoBRAL Sandra CARVALHo Filipe silva CMEMS-UMinho University of MinhoGuimarães 4800058Portugal LABBELS-Associate Laboratory Guimarães 4800058Portugal CEMMPRE-Center for Mechanical Engineering Materials and ProcessesUniversity of CoimbraRua Luís Reis SantosCoimbra 3030-788Portugal MAHLE Componentes de MotoresS.A.Núcleo Industrial de MurtedeCantanhede 3060-372Portugal

The radial surface coating layer of compression piston rings is used to improve their wear resistance during the internal combustion engine ***,at top dead centers,the friction coefficient of the piston ring–cylinder liner pair is detrimental to the engine’s tribological *** this work,dimples with different texture dimensions and densities were tested in a home-developed *** friction coefficient was measured for all samples,and for those with the best results,their wear resistance was *** texture with an aspect ratio of 0.25 and a density area of 15%reported the best tribological results.

关键词： piston ring surface texture friction wear

Appropriateness of the study of iron deficiency anemia prior to referral for small bowel evaluation at a tertiary center

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World Journal of Gastroenterology 2017年第24期23卷 4444-4453页

作者： Jaime Pereira Rodrigues Rolando Pinho Joana silva Ana Ponte Mafalda Sousa Joao Carlos silva Joao Carvalho Department of Gastroenterology Centro Hospitalar Vila Nova de Gaia/EspinhoRua Conceicao FernandesVila Nova de Gaia

To evaluate the adequacy of the study of iron deficiency anemia (IDA) in real life practice prior to referral to a gastroenterology department for small bowel evaluation. METHoDSAll consecutive patients referred to a gastroenterology department for small bowel investigation due to iron deficiency anemia, between January 2013 and December 2015 were included. Both patients referred from general practitioners or directly from different hospital departments were selected. Relevant clinical information regarding prior anemia workup was retrospectively collected from medical records. An appropriate pre-referral study was considered the execution of esophagogastroduodenoscopy (EGD) with Helicobacter pylori (H. pylori) investigation, colonoscopy with quality standards (recent, total and with adequate preparation) and celiac disease (CD) screening (through serologic testing and/or histopathological investigation). RESULTSA total of 77 patients (58.4% female, mean age 67.1 ± 16.7 years) were included. Most (53.2%) patients were referred from general practitioners, 41.6% from other hospital specialties and 5.2% directly from the emergency department. The mean pre-referral hemoglobin concentration was 8.8 ± 2.0 g/dL and the majority of anemias had microcytic (71.4%) and hypochromic (72.7%) characteristics. 77.9% of patients presented with an incomplete pre-referral study: EGD in 97.4%, with H. pylori investigation in 58.3%, colonoscopy with quality criteria in 63.6%, and CD screening in 24.7%. Patients with an appropriate study at the time of referral were younger (48.7 ± 17.7 vs 72.3 ± 12.3 years, P owel evaluation was ultimately undertaken in 72.7% of patients, with a more frequent evaluation in patients with a quality colonoscopy at referral (78.6% vs 23.8%); P oR = 11.7, 95%CI: 3.6-38.6). The most common diagnosis regarded as the likely cause of IDA was small bowel angioectasia (18.2%) but additional causes were also found in the upper and lower ga

关键词： Iron deficiency anemia Colonoscopy Celiac disease Esophagogastroduodenoscopy Helicobacter pylori Small bowel