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Tailoring the partitioning of proteins using ionic liquids as adjuvants in polymer-polymer aqueous biphasic systems

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Green Chemical Engineering 2022年第4期3卷 328-337页

作者： Flavia F.magalhaes matheus m.pereira Rita de Cassia Superbi de Sousa Ana P.m.Tavares Joao A.P.Coutinho mara G.Freire CICECO-Aveiro Institute of materials Department of ChemistryUniversity of AveiroAveiro3810-193Portugal Separation Process Laboratory(LPS) Department of Food TechnologyFederal University of Viçosa(UFV)P.H.Rolfs Av.s/n36570-000 ViçosaMGBrazil

Aqueous biphasic systems(ABS)are promising for proteins purification;however,when dealing with samples comprising several proteins,the selectivity towards a target protein is difficult to *** this work,the addition of ionic liquids(ILs)as adjuvants(5 wt%and 10 wt%)in ABS composed of polyethylene glycol(PEG)and dextran was investigated to tailor proteins partitioning between the coexisting *** liquid-liquid phase diagrams were determined at 298 K,followed by partition studies of three proteins(bovine serum albumin(BSA),immunoglobulin G(IgG),and cytochrome C(Cyt C)).Partition coefficients of IgG and BSA indicate the preference of both proteins to the dextran-rich phase,whereas Cyt C has no preferential partitioning between the *** addition of chloride-based ILs as adjuvants allows to increase or decrease the partition coefficients,thus tailoring the proteins partitioning between the *** partitioning essentially depends on the IL content in each phase,whereas Cyt C and IgG partitioning is ruled by the ILs chemical structure and established *** docking was carried out to address the ILs effect on the proteins partitioning,supporting experimental observations,while identifying the specific interactions *** partition of each protein in polymer-salt ABS with ILs as adjuvants was determined,demonstrating the higher tailoring ability of polymer-polymer ABS when adding ***,the partition of each protein in presence of the remaining ones was determined,as well as the selectivity of the studied systems to separate each pair of proteins,paving the way for their use in liquidliquid chromatography.

关键词： Aqueous biphasic systems Polymer-polymer systems Protein partition Ionic liquids Adjuvants

Cr（V）involvementin the toxicity pathway of testicular damage

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Asian Journal of Andrology 2002年第2期4卷 153-155页

作者： m.L.pereira T.m.Santos 等 DepartmentofBiology Departmentofchemistry UniversityofAveriro3810－193AveiroPortugal

AIm:The functional integrity of the blood-testis barrier (BTB) in male mice exposed to Cr(V) was studied in order to clarify the mechanism underlying testicular injury.mETHODS:Adult male mice were subcutaneously injected repeated doses of 8.02 micromol (0.5 ml) of Cr/*** for 5 days. Animals receiving a similar volume of bis(hydroxyethyl)-aminotris(hydroxymethyl)methane buffer (BT) were used as controls. The animals were sacrificed on day 6 and small fragments of seminiferous tubules, approximately 8-10 mm length, were incised and sutured at both ends. They were exposed in vitro to horseradish peroxidase-containing culture medium for 10 minutes. Tissues were then fixed and processed for ultrastructural studies.RESULTS:Controls and Cr(V)-treated group resulted in the uptake of the tracer by Sertoli cells. However, the major finding consisted in the permeability of the BTB only in the Cr(V)-group, as evidenced by the presence of the tracer within the junctions between the neighbouring Sertoli cells.CONCLUSION:The BTB is disrupted in mice submitted to Cr(V). The permeability of the BTB is a crucial feature to be investigated for the understanding of lesions within the seminiferous tubule.

关键词： Blood-testis barrier Cr(V) Horseradish peroxidase Integrity Spermatogenesis

The inception of a Paleotethyan magmatic arc in Iberia

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Geoscience Frontiers 2015年第2期6卷 297-306页

作者： m.F.pereira A.Castro C.Fernández IDL Departamento de Geociências ECT Universidade de évora Departamento de Geología Universidad de Huelva Departamento de Geodinámica y Paleontología Universidad de Huelva

This paper presents a compilation of recent U-Pb （zircon） ages of late Carboniferous-early Permian （LC EP） calc-alkaline batholiths from lberia, together with a petrogenetic interpretation of magma generation based on comparisons with mesozoic and Tertiary Cordilleran batholiths and experimental melts. Zircon U-Pb ages distributed over the range ca. 315-280 ma, indicate a linkage between calc-alkaline magmatism, Iberian orocline generation and Paleotethys subduction. It is also shown that Iberian LC-EP calcalkaline batholiths present unequivocal subduction-related features comparable with typical Cordilleran batholiths of the Pacific Americas active margin, although geochemical features were partially obscured by local modifications of magmas at the level of emplacement by country rock assimilation. When and how LC-EP calc-alkaline batholiths formed in Iberia is then discussed, and a new and somewhat controversial interpretation for their sources and tectonic setting （plume-assisted relamination） is suggested. The batholiths are proposed to have formed during the subduction of the Paleotethys oceanic plate （Pangaea self-subduction） and, consequently, they are unrelated to Variscan collision. The origin of the Iberian batholiths is related to the Eurasian active margin and probably represents the inception of a Paleotethvan arc in the core of Pangaea.

关键词： Permo-Carboniferous Calc-alkaline arc-related batholiths Pangaea Paleotethys subduction Variscan and Cimmerian cycles

Vertical stratification of bat assemblages in flooded and unflooded Amazonian forests

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Current Zoology 2010年第4期56卷 469-478页

作者： maria Joo Ramos pereira Joo Tiago mARQUES Jorge m.PALmEIRIm Centro de Biologia Ambiental Departamento de Biologia Animal Faculdade de Ciências da Universidade de Lisboa Instituto de Desenvolvimento Sustentvel mamirau

Tropical rainforests usually have multiple strata that results in a vertical stratification of ecological opportunities foranimals. We investigated if this stratification influences the way bats use the vertical space in flooded and unflooded forests of theCentral Amazon. Using mist-nets set in the canopy (17 to 35 m high) and in the understorey (0 to 3 m high) we sampled four sitesin upland unflooded forests (terra firme), three in forests seasonally flooded by nutrient-rich water (varzea), and three in forestsseasonally flooded by nutrient-poor water (igapo). Using rarefaction curves we found that species richness in the understorey andcanopy were very similar. An ordination analysis clearly separated the bat assemblages of the canopy from those of the understorey inboth flooded and unflooded habitats. Gleaning carnivores were clearly associated with the understorey, whereas frugivores wereabundant in both strata. Of the frugivores, Carollinae and some Stenodermatinae were understorey specialists, but several Stenodermatinaemostly used the canopy. The first group mainly includes species that, in general, feed on fruits of understorey shrubs,whereas the second group feed on figs and other canopy fruits. We conclude that vertical stratification in bat communities occurseven within forests with lower canopy heights, such as Amazonian seasonally flooded forests, and that the vertical distribution ofbat species is closely related to their diet and foraging behaviour.

关键词： Amazon Bats Chiroptera Vertical stratification Floodplain

Tunable Super-Structured Fiber Bragg Gratings with Perfect Sequences Based on m-Sequence

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Journal of Electronic Science and Technology 2017年第4期15卷 358-363页

作者： Joao S.pereira marco P.m.Ferreira marko Gasparovic Instituto de Telecomunicacoes Lisboa 1049-001 Portugal Institute Polytechnic of Leiria Leiria 2411-901 Portugal Centro de Investigaao em Informaica e Comunicacoes Institute Polytechnic of Leiria Leiria 2411-901Portugal

Recently, a tunable fiber Bragg grating(FBG) was developed by using stress-responsive colloidal crystals. In this paper, we have simulated the application of these nanoparticles into the super-structured fiber Bragg grating(SSFBG) written with perfect sequences derived from a short maximal-length sequence. A tunable SSFBG will be available to overcome the prohibitive temperature variation of the optical codecs. Nevertheless,we presented a method to implement coherent time spreading optical code-division multiple-access(OCDmA) where a unique code(or perfect sequence) can be reused and mixed with different wavelengths to obtain a tunable wavelength-division multiplexing(WDm)system. In order to maximize the binary throughput, we have selected a unique short maximal-length sequence composed of 7 chips that can be tuned with 7 different optical wavelengths. We found thousands of different tunable combinations that presented power contrast ratios(P/C) higher than 12 dB. When a WDm-OCDmA system used 2 different combinations simultaneously, the perfect binary detection with error correction codes was achieved successfully. The tunable SSFBG with colloidal crystals will be a simple and good alternative choice for fiber-to-the-home(FTTH) communications.

关键词： Optical code-division multiple-access(OCDmA) super-structured fiber Bragg grating(SSFBG) wavelength-division multiplexing OCDmA(WDm-OCDmA)

用10mHz参考源产生一个9.997925mHz信号

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电子产品世界 1997年第8期4卷 79-79,78页

作者： m.pereira F.Perez-Fontan 冰西班牙Vigo大学

很多的应用都需要相对于给定的参考源合成一个略有偏移的频率.本设计思路是利用10mHz基准源用一个电路来产生9.997925mHz信号.其频率偏移是很低的(只有2kHz),这对于混频器和滤波器的设计造成严格的约束.本电路利用一个锁相环基方案(图1)... 详细信息

很多的应用都需要相对于给定的参考源合成一个略有偏移的频率.本设计思路是利用10mHz基准源用一个电路来产生9.997925mHz信号.其频率偏移是很低的(只有2kHz),这对于混频器和滤波器的设计造成严格的约束.本电路利用一个锁相环基方案(图1).图2描述所建议的电路的详细设计图.在频域中,相位传递函数是:(Φo(S))/(Φi(S))=(Kmp)/(nq) (F(S))/(mpS+KF(S))(1)式中Φi(S)和Φo(S)是输入和输出相位的拉普拉斯变换,F(S)是环的频率响应.

关键词：电子电路混频器参考源滤波器设计

Inductively coupled plasma emission spectroscopic and flame photometric analysis of goat epididymal fluid

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Asian Journal of Andrology 2000年第4期2卷 288-292页

作者： meenakshi Gaur Vikas Pruthi Ramasare Prasad Ben m.J.pereira Reproductive Biology Laboratory Dept. of Bioscience and Biotechnology University of Roorkee Roorkee-247 667 U. P. IndiaReproductive Biology Laboratory Dept. of Bioscience and Biotechnology University of Roorkee Roorkee-247 667 U. P. IndiaReproductive Biology Laboratory Dept. of Bioscience and Biotechnology University of Roorkee Roorkee-247 667 U. P. IndiaReproductive Biology Laboratory Dept. of Bioscience and Biotechnology University of Roorkee Roorkee-247 667 U. P. India

Aim: The elemental composition of the epididymal luminal fluid (ELF) in adult goat ( Capra indica) was investigat-ed. methods: ELF was collected by micropuncture from twelve sites along the epididymal duct. The elementalcontents was analyzed with inductively coupled plasma (ICP) emission spectroscopy, a microanalytical technique thatcan simultaneously measure many elements in minute volumes of sample. The Na and K concentrations were determinedby flame photometry. Results: ICP spectroscopy showed the presence of copper, calcium, nickel, iron, magne-sium, chromium, titanium and zinc in ELF, with fluctuating levels at different sites along the length of the ***, cobalt, lead and manganese were not fotmd. The Na^+ / K^+ ratio was seen to be higher at the initial seg-ments of the epididymis and lower at the distal. Conclusion: It is proposed that the observed characteristic distribu-tion of elements in ELF may have far reaching implications in sperm maturation and storage known to occur in the epi-didymis. (Asian J Androl 2000 Dec; 2: 288-292)

关键词： goat epididymis epididymal luminal fluid elements spectroscopy flame photometry

Performance of evolutionary optimized machine learning for modeling total organic carbon in core samples of shale gas fields

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Petroleum 2024年第1期10卷 150-164页

作者： Leonardo Goliatt C.m.Saporetti L.C.Oliveira E.pereira Department of Computational and Applied mechanics Federal University of Juiz de ForaJuiz de ForaBrazil Department of Computational modeling Polytechnic InstituteRio de Janeiro State UniversityNova FriburgoBrazil Petrobras Rio de JaneiroBrazil Department of Stratigraphy and Paleontology Rio de Janeiro State UniversityRio de JaneiroBrazil

Rock samples'TOC content is the best indicator of the organic matter in source *** origin rock samples’analysis is used to calculate it manually by *** method requires time and resources because it relies on samples from many well intervals in source ***,research has been done to aid this *** learning algorithms can estimate total organic carbon instead of well logs and stratigraphic *** light of these efforts,the current work present a study on automating the total organic carbon estimation using machine learning approaches improved by an evolutionary methodology to give the model flexibility and *** algorithms,differential evolution,particle swarm optimization,grey wolf optimization,artificial bee colony,and evolution strategies were used to improve machine learning models to predict *** six metaheuristics were integrated into four machine learning methods:extreme learning machine,elastic net linear model,linear support vector regression,and multivariate adaptive regression *** samples from the YuDong-Nan shale gas field,located in the Sichuan basin,were used to evaluate the hybrid *** findings show that combining machine learning models with an evolutionary algorithms in a hybrid fashion produce flexible models that accurately predict *** results show that,independent of the metaheuristic used to guide the model selection,optimized extreme learning machines attained the best performance scores according to six *** hybrid models can be used in exploratory geological research,particularly for unconventional oil and gas resources.

关键词： Total organic carbon Hybrid models Automated machine learning Evolutionary algorithms Geology

O_(3) based advanced oxidation for ibuprofen degradation

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Chinese Journal of Chemical Engineering 2022年第2期35卷 277-284页

作者： Vitória m.Almeida Carla A.Orge m.Fernando R.pereira O.SaloméG.P.Soares Laboratory of Separation and Reaction Engineering-Laboratory of Catalysis and materials (LSRE-LCM)Faculdade de Engenharia da Universidade do PortoRua Dr.Roberto Frias4200-465 PortoPortugal

The degradation of the anti-inflammatory ibuprofen(IBP)was evaluated by several advanced oxidation *** was treated by single ozonation and oxidation with hydrogen peroxide(H_(2)O_(2)),as well as a combination of these *** order to improve the efficiency,the presence of catalysts such as original carbon nanotubes,labelled as CNT,and iron oxide supported on carbon nanotubes,named as Fe/CNT sample,was *** evolution of IBP degradation,mineralization and toxicity of the solutions was *** formation of intermediates was also *** the non-catalytic processes,IBP was faster removed by single ozonation,whereas no significant total organic carbon(TOC)removal was *** with H_(2)O_(2) did not present satisfactory *** ozone and H_(2)O_(2) were combined,a higher mineralization was attained(70%after 180 min of reaction).On the other hand,in the catalytic processes,this combined process allowed the fastest IBP *** terms of mineralization degree,the presence of Fe/CNT increases the removal rate in the first hour of reaction,achieving a TOC removal of 85%.Four compounds were detected as *** treated solutions presented lower toxicity than the initial solution,suggesting that the released intermediates during applied processes are less toxic.

关键词： Advanced oxidation processes Catalysts Emerging pollutants Ibuprofen