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Coating independent cytotoxicity of citrate-and PEG-coated silver nanoparticles on a human hepatoma cell line

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Journal of Environmental Sciences 2017年第1期29卷 191-201页

作者： Veronica Bastos Jose M.P.ferreira-de-Oliveira Joana Carrola Ana L.Daniel-da-Silva iola f.duarte Conceicao Santos Helena Oliveira CESAM&Laboratory of Biotechnology and Cytomics Department of BiologyUniversity of Aveiro3810-193 AveiroPortugal CICECO-Aveiro Institute of Materials Department of ChemistryUniversity of Aveiro3810-193 AveiroPortugal Department of Biology Faculty of SciencesUniversity of Porto4169-007 PortoPortugal

The antibacterial potential of silver nanoparticles（AgNPs） resulted in their increasing incorporation into consumer,industrial and biomedical ***,human and environmental exposure to AgNPs（either as an engineered product or a contaminant）supports the emergent research on the features conferring them different toxicity *** this study,30 ran AgNPs coated with citrate or poly（ethylene glycol）（PEG） were used to assess the influence of coating on the effects produced on a human hepatoma cell line（HepG2）,namely in terms of viability,apoptosis,apoptotic related genes,cell cycle and cyclins gene *** types of coated AgNPs decreased cell proliferation and viability with a similar toxicity *** the concentrations used（11 and 5 μg/mL corresponding to IC50 and-IC10 levels,respectively） the amount of cells undergoing apoptosis was not significant and the apoptotic related genes BCL2（anti-apoptotic gene）and BAX（pro-apoptotic gene） were both ***,both AgNPs affected HepG2 cell cycle progression at the higher concentration（11 μg/mL） by increasing the percentage of cells in S（synthesis phase） and G2（Gap 2 phase） *** the cell-cycle related genes,the expression of cyclin B1 and cyclin E1 genes were ***,this work has shown that citrate- and PEG-coated AgNPs impact on HepG2 apoptotic gene expression,cell cycle dynamics and cyclin regulation in a similar *** research is needed to determine the properties that confer AgNPs at lower toxicity,since their use has proved helpful in several industrial and biomedical contexts.

关键词： Silver nanoparticles(AgNPs) Citrate Polyethylene glycol)(PEG) HepG2 cells Cytotoxicity Nanotoxicology

Low crude protein formulation with supplemental amino acids for its impacts on intestinal health and growth performance of growing-finishing pigs

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Journal of Animal Science and Biotechnology 2024年第4期15卷 1590-1606页

作者： Marcos Elias duarte Wanpuech Parnsen Shihai Zhang Marvio L.T.Abreu Sung Woo Kim Department of Animal Science North Carolina State UniversityRaleighNC 27695USA

Background Low crude protein(CP)formulations with supplemental amino acids(AA)are used to enhance intestinal health,reduce costs,minimize environmental impact,and maintain growth performance of ***,extensive reduction of dietary CP can compromise growth performance due to limited synthesis of non-essential AA and limited availability of bioactive compounds from protein supplements even when AA requirements are ***,implementing a low CP formulation can increase the net energy(NE)content in feeds causing excessive fat *** supplementation of functional AA,coupled with low CP formulation could further enhance intestinal health and glucose metabolism,improving nitrogen utilization,and growth *** experiments were conducted to evaluate the effects of low CP formulations with supplemental AA on the intestinal health and growth performance of growing-finishing *** In Exp.1,90 pigs(19.7±1.1 kg,45 barrows and 45 gilts)were assigned to 3 treatments:CON(18.0%CP,supplementing Lys,Met,and Thr),LCP(16.0%CP,supplementing Lys,Met,Thr,Trp,and Val),and LCPT(16.1%CP,LCP+0.05%SID Trp).In Exp.2,72 pigs(34.2±4.2 kg BW)were assigned to 3 treatments:CON(17.7%CP,meeting the requirements of Lys,Met,Thr,and Trp);LCP(15.0%CP,meeting Lys,Thr,Trp,Met,Val,Ile,and Phe);and VLCP(12.8%CP,meeting Lys,Thr,Trp,Met,Val,Ile,Phe,His,and Leu).In Exp.3,72 pigs(54.1±5.9 kg BW)were assigned to 3 treatments and fed experimental diets for 3 phases(grower 2,finishing 1,and finishing 2).Treatments were CON(18.0%,13.8%,12.7%CP for 3 phases;meeting Lys,Met,Thr,and Trp);LCP(13.5%,11.4%,10.4%CP for 3 phases;meeting Lys,Thr,Trp,Met,Val,Ile,and Phe);and LCPG(14.1%,12.8%,11.1%CP for 3 phases;LCP+Glu to match SID Glu with CON).All diets had 2.6 Mcal/kg *** In Exp.1,overall,the growth performance did not differ among *** LCPT increased(Pf2hc,and B0AT exp

关键词： Amino acids Growing-finishing pigs Growth performance Intestinal health Low crude protein formulation Net energy

Pancreatic neuroendocrine tumors:Are tumors smaller than 2 cm truly indolent?

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1756-1762页

作者： Sergio Hoyos Pablo Posada-Moreno Natalia Guzman-Arango Romario Chanci-Drago Jaime Chavez Alvaro Andrés-duarte Santiago Salazar-Ochoa Hepatobilary and Liver Transplant Unit Hospital Pablo Tobon Uribe and Gastrohepathology Group Universidad de AntioquiaMedellin 050034AntioquiaColombia Department of General Surgery Universidad Pontificia BolivarianaMedellín 050034AntioquiaColombia

BACKGROUND Pancreatic neuroendocrine tumors(PNETs)are relatively rare but rank as the second most common pancreatic *** can be functional,causing early metabolic disturbances due to hormone secretion,or non-functional and diagnosed later based on tumor size-related *** diagnoses of PNETs under 2 cm in size have sparked debates about their management;some practitioners advocate for surgical removal and others suggest observation due to the tumors’lower potential for ***,it is unclear whether managing these small tumors expectantly is truly *** To evaluate poor prognostic factors in PNETs based on tumor size(>2 cm orference hospital in Medellín,*** assess patient survival,quarterly follow-ups were conducted during the first year after surgery,followed by semi-annual con-sultations at the hospital's hepatobiliary surgery *** variables were described using absolute and relative frequencies,and quantitative variables were expressed using measures of central tendency and their corresponding measures of *** The presence of lymph node involvement,neural involvement,and lymphovascular invasion were all associated with an increased risk of mortality,with hazard ratios of 5.68(95%CI:1.26–25.61,P=0.024),6.44(95%CI:1.43–28.93,P=0.015),and 24.87(95%CI:2.98–207.19,P=0.003),*** involvement and lymphovascular invasion were present in tumors smaller than 2 cm in diameter and those larger than 2 cm in *** recurrence rates between the two tumor groups were furthermore similar:18.2%for tumors smaller than 2 cm and 21.4%for tumors larger than 2 *** survival was additionally comparable between the two tumor *** Tumor size does not dictate prognosis;lymph node and lymphovascular involvement a

关键词： Neuroendocrine tumor Pancreatic neoplasm Pancreas Pancreatic neuroendocrine neoplasm Pancreatic neuroendocrine tumors

Natural and anthropogenic sources of lead, zinc, and nickel in sediments of Lake Izabal, Guatemala

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Journal of Environmental Sciences 2020年第10期32卷 117-126页

作者： Elisandra Hernandez Jonathan Obrist-farner Mark Brenner William f.Kenney Jason H.Curtis Edward duarte Geosciences and Geological and Petroleum Engineering Department Missouri Uniuersity of Science and Technology.RollaMO 65409USA. Department of Geological Sciences University of FloridaGainesvilleFL 32611USA Land Use and Enuironmental Change Institute Uniuersity of FloridaGainesvilleFL 32611USA Escuela de Quimica Universidad de San Carlos de Guatemala01012Guatermala

Sediments in Lake Izabal,Guatemala,contain substantial lead (Pb),zinc (Zn),and nickel (Ni).The lack of historical data for heavy metal concentrations in the sediments makes it difficult to determine the sources or evaluate whether inputs of metals to the lake have changed through *** measured the relative abundances and concentrations of Pb,Zn,and Ni by X-Ray fluorescence core scanning and by Inductively Coupled Plasma Optical Emission Spectrometry in three sediment cores to explore stratigraphic distributions of metals in the lake *** amounts of Pb and Zn in the core taken near the Polochic Delta suggest that galena and sphalerite mining increased Pb and Zn delivery to Lake Izabal between ~1945 and 1965 *** up-core Ni increase in the core taken near a different mine on the north shore of Lake Izabal suggests that recent nickel mining operations led to an increase in Ni concentrations in the local sediments,but amounts in the other cores indicate that Ni is not widely distributed throughout the *** cores from Lake Izabal are reliable recorders of heavy metal input to the lake,and were measured to establish background metal levels,which would otherwise be *** of Pb,Zn,and Ni in older,pre-20th-century Lake Izabal sediments reflect input from natural erosion of *** results provide previously unavailable estimates of background metal concentrations in Lake Izabal before the onset of *** results are necessary for future monitoring related to mining contamination of the lake ecosystem.

关键词： Lake Izabal Heavy metals Lead contamination Anthropogenic impacts Mining Guatemala

Stream-dwelling fungal decomposer communities along a gradient of eutrophication unraveled by 454 pyrosequencing

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fungal Diversity 2015年第1期70卷 127-148页

作者： S.duarte f.Bärlocher J.Trabulo f.Cássio C.Pascoal Centre of Molecular and Environmental Biology(CBMA) Department of BiologyUniversity of MinhoCampus de Gualtar4710-057 BragaPortugal Department of Biology Mount Allison UniversitySackvilleNB E4L 1G7Canada

Microbial decomposers,especially a fungal group called aquatic hyphomycetes,play a critical role in processing plant litter in freshwaters by increasing its palatability to invertebrate ***,communities of aquatic hyphomycetes have been assessed through the identification of spores,which misses non-sporulating *** new technologies,454 pyrosequencing stands out as most promising for large-scale species ***,very few attempts have been made to validate its effectiveness for assessing the diversity of stream-dwelling fungal *** attempted to gain greater insight into the diversity of aquatic fungal communities in streams exposed to various degrees of eutrophication by using the 454 pyrosequencing technology.A total of 173,889 ITS2 pyrosequencing reads with hits for fungi were obtained from the 5 investigated *** majority of operational taxonomic units(OTUs)belonged to Ascomycota and the identification to the genus level was achieved for 169 *** the total,135,257 reads(ca.78%)showed close affinities to aquatic hyphomycete *** showed declining fungal diversity in the most eutrophic streams,which was congruent with a reduced diversity found through spore *** patterns revealed by connecting representative OTUs to ITS sequences from aquatic hyphomycetes were similar to those determined by traditional spore identification ***,454 pyrosequencing provided a more comprehensive view of fungal diversity;it captured almost twice as many taxa as spore *** study vali-dates the effectiveness of 454 pyrosequencing for surveying the diversity of stream-dwelling fungal decomposer *** application may accelerate the use of these communities for monitoring the integrity of freshwaters.

关键词： freshwater ecosystems Plant litter decomposition Aquatic fungi ITS region

Dietary inclusion of multispecies probiotics to reduce the severity of post-weaning diarrhea caused by Escherichia coli f18+ in pigs

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Animal Nutrition 2021年第2期7卷 326-333页

作者： Yawang Sun Marcos E.duarte Sung Woo Kim Department of Animal Science North Carolina State UniversityRaleighNC27695United States

This study was aimed to determine the efficacy of multispecies probiotics in reducing the severity of post-weaning diarrhea caused by enterotoxigenic Escherichia coli(ETEC)f18+on newly weaned ***-two pigs(16 barrows and 16 gilts,BW=6.99±0.33 kg)at 21 d of age were individually allotted in a randomized complete block design with 2×2 factorial arrangement of *** were selected from sows not infected previously and not vaccinated against *** were fed experimental diets for 25 d based on 10 d phase 1 and 15 d phase *** factors were ETEC challenge(oral inoculation of saline solution or *** f18+at 2×109 CfU)and probiotics(none or multispecies probiotics 0.15%and 0.10%for phase 1 and 2,respectively).Body weight and feed intake were measured on d 5,9,13,19,and *** scores were measured *** samples were taken on d 19 and *** d 25,all pigs were euthanized to obtain samples of digesta,intestinal tissues,and *** tumor necrosis factor alpha(TNfα),malondialdehyde(MDA),peptide YY(PYY),and neuropeptide Y(NPY)were measured in serum and intestinal *** were analyzed using the MIXED procedure of *** fecal score of pigs was increased(Pfα,increased(Pfα,tended to reduce(P=0.064)jejunal MDA,tended to increase(P=0.092)serum PYY,and increased(Pformance of pigs were not affected by ETEC challenge,whereas the probiotics increased(PfI and tended to increase(P-0.069)G:f *** conclusion,ETEC f18+challenge caused diarrhea,intestinal inflammation and morphological damages without affecting the growth *** multispecies probiotics enhanced growth pe

关键词： Escherichia coli Growth performance Gut health Nursery pig Post-weaning diarrhea Probiotic

Does microfinance foster the development of its clients?A bibliometric analysis and systematic literature review

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financial Innovation 2022年第1期8卷 1023-1057页

作者： João Paulo Coelho Ribeiro fábio duarte Ana Paula Matias Gama CIICESI ESTGPolitécnico do PortoPortoPortugal School of Economics and Management and cef.upUniversity of PortoPortoPortugal Research Center in Business Science(NECE) University of Beira InteriorCovilhãPortugal

This paper conducts a scientometric analysis and systematic literature review to identify the trends in microfinance outcomes from the perspective of their recipients,specifically more vulnerable people,while also focusing on the demand *** the keywords“co-occurrence networks”and“citation networks,”we examined 524 studies indexed on the ISI Web of Science database between 2012 and March *** subsequent content analysis of bibliometric-coupled articles concerns the main research topics in this field:the socioeconomic outcomes of microfinance,the dichotomy between social performance and the mission drift of microfinance institutions,and how entrepreneurship and financial innovation,specifically through crowdfunding,mitigate poverty and empower the more *** findings reinforce the idea that microfinance constitutes a distinct field of development thinking,and indicate that a more holistic approach should be adopted to boost microfinance outcomes through a better understanding of their *** trends in this field will help policymakers,regulators,and academics to examine the nuts and bolts of microfinance and identify the most relevant areas of intervention.

关键词： Microfinance Microcredit Bibliometric analysis Economics Business finance

Lightning Overvoltages on Rural Distribution Lines

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高电压技术 2008年第12期34卷 2564-2569页

作者： A. Piantini D. M. duarte f. Romero CENDAT-IEE/USP University of Sao Paulo Av. Prof. Luciano Gualberto 1289 Sao Paulo Brazil

This paper presents information concerning the characteristics of lightning overvoltages on overhead power distribution *** on the protection measures against transients caused by both direct and indirect strokes is a... 详细信息

关键词：农村配电线路雷电过电压保护间接雷击

Mitigation of spectral leakage for single carrier, block-processing cognitive radio receivers

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Digital Communications and Networks 2018年第2期4卷 106-110页

作者： Adam C. Polak Mark Wagner Marco f. duarte Robert W. Jackson Dennis L. Goeckel Electrical and Computer Engineering Department University of Massachusetts Amherst United States

Cognitive Radio （CR） is a multiuser, wireless communication concept that allows for a dynamic and adaptive assignment of spectral resources. The coexistence of multiple users, often transmitting at significantly different power levels, makes CR receivers vulnerable to spectral leakage caused by components＇ nonlinearities and timetruncation of the processed signal records. In this work we propose a method for mitigating the latter with an adaptive choice of the length of the processing block size. With simulations we show that a significant leakage reduction that leads to receiver dynamic range improvement of around 10 dB can be achieved with the proposed method.

关键词： Spectral leakage Dynamic range Single carrier block transmission Interference White space Cognitive radio