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Ecological succession of benthic organisms on niche-type artificial reefs

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Ecological Processes 2020年第1期9卷 433-442页

作者： María-Isabel Toledo Pamela Torres Cristina díaz Victor zamora Jesús López Germán Olivares Escuela de Ciencias del Mar Facultad de Ciencias del Mar y GeografíaPontificia Universidad Católica de ValparaísoValparaísoChile

As part of efforts to restore fishery resources and recover damaged coastal ecosystems,artificial reefs are often anchored on the seafloor in coastal zones,to provide new habitats for marine *** aim of the study was to describe the structure of a community of benthic invertebrates colonising a niche-type artificial reef(AATN in Spanish).Nine structures were anchored at depths of 16±1.5 m for 99 weeks(22 months)in the Area of Benthic Resource Management and Exploitation(AMERB)in coastal waters of the Region of Bio Bio,*** results showed that,at 3 months from submersion of the NTAR,much of the artificial substrate remained bare and there were only low levels of specimens of Balanus ***,showing mean coverage of 11.26%,and even lower proportions of Rhodophyta,with mean coverage of 0.34%.At 6 months,the presence of hydrozoans was seen,decreasing the coverage of the barnacles,which was aided further at 8 months with the arrival of barnacle predatory *** 8 months,new benthic invertebrates appeared and competed for the *** included sponges and *** 99 weeks,the hydrozoans dominated the substrate,followed by barnacles and Rhodophyta,the first colonising organisms,leading to colonisation by motile macro-invertebrates,mainly consisting of crustaceans,echinoderms and *** AATN artificial system provides an ideal substrate for the development of early ecological succession and the use of this technology should be feasible in the recovery process of habitat damaged by anthropogenic actions and climate change.

关键词： Artificial reefs Ecological succession Colonisation Benthic organisms Balanus sp. Rhodophyta Hydrozoans

Systematic study of the dependence of magnetic and structural properties of Nd2Fe14B powders on the average particle size

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Journal of Rare Earths 2020年第9期38卷 961-968,I0002页

作者： J.F.durán Perdomo G.A.Pérez Alcázar H.d.Colorado J.A.Tabares L.E.zamora J.J.S.Garitaonandia department of Physics University of ValleA.A.25360 CaliColombia Applied Physics II department Basque Country University48080 BilbaoSpain

A systematic study of the magnetic and structural properties dependence on the particle size was *** this,commercial NdFeB powder was separated into five different mean particle sizes using ***,from the original powder,eleven samples were also produced by mechanical milling assisted by surfactant,using various milling times.A total of sixteen samples were studied by scanning electron microscopy(SEM),X-ray diffraction(XRd),vibrating sample magnetometry(VSM),and Mdssbauer spectrometry(MS).The particle sizes of the samples vary from the micrometer to the nanometer *** crystallite size decreases with decreasing particle *** result indicates that the Nd2Fe14B phase is found in all the samples,and the presence of this phase is also corroborated by MS using six sextets for fitting their spectra,with an additional singlet corresponding to the Nd1.1Fe4B4 *** mean hyperfine magnetic field increases with increasing particle size because the magnetic dipolar interaction between the magnetic moment of the particles increases with particle *** the VSM measurements the magnetic energy density(BH)max values were calculated for different particle sizes,and their maximum value of 34.45 MGOe is obtained for the sample with the particle size of 60μm.

关键词： Hard magnetic material XRd Mossbauer spectrometry Magnetization Particle size Rare earths

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Current Zoology 2020年第5期66卷 493-503页

作者： Francesc Rubio-Gracia Emili Garcia-Berthou Helena Guasch Lluis zamora Anna Vila-Gispert Institute of Aquatic Ecology University of Girona17003 GironaSpain Integrative Freshwater Ecology Group Centre d'Tstudis Avanqats de BlanesCSIC17300 BlanesSpain

Energy metabolism fuels swimming and other biological *** compared the swimming performance and energy metabolism within and across eight freshwater fish *** swim tunnel respirometers,we measured the standard metabolic rate(SMR)and maximum metabolic rate(MMR)and calculated the critical swimming speed(Ucrit).We accounted for body size,metabolic traits,and some morphometric ratios in an effort to understand the extent and underlying causes of *** mass was largely the best predictor of swimming capacity and metabolic traits within ***,we found that predictive models using total length or SMR,in addition to body mass,signicantly in creased the explained variation of Ucrit and MMR in certain fish *** predictive models also underlined that,once body mass has been accounted for,Ucrit can be independently affected by total length or *** study exemplifies the utility of multiple regression models to assess within-species *** interspecific level,our results showed that variation in UcriX can partly be explained by the variation in the interrelated traits of MMR,finen ess,and muscle *** the species studied,bleak Al burn us alburnus performed best in terms of swimming performance and *** contrast,pumpkinseed Lepomis gibbosus showed very poor swimming performance,but attained lower mass-specific cost of transport(MCOT)than some rheophilic species,possibly reflecting a cost reduction strategy to compensate for hydrod yn amic *** con elusion,this study provides insight into the key factors in fluenci ng the swimming performa nee of fish at both intra-and in terspecific levels.

关键词： body size maximal metabolic rate morphology swimming efficiency

Effect of cobalt substitution on structure and magnetic properties of Nd0.4Zr0.6Fe10-xCoxSi2（x =0-3） alloys and their ribbons

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Journal of Rare Earths 2019年第10期37卷 1096-1101页

作者： M.Gjoka C.Sarafidis G.Giannopoulos d.Niarchos G.Hadjipanayis J.A.Tabares G.A.Pérez Alcázar L.E.zamora Institute of Nanoscience and Nanotechnology NCSR Demokritos15310AthensGreece department of Physics and Astronomy University of DelawareNewarkDEUSA department of Physics Aristotle University of Thessaloniki54124ThessalonikiGreece departamento de Física Universidad del ValleA.A.25360CaliColombia

This study reports the stabilization of the RFe12-type based compounds where part of R and Fe are substituted with Zr and Co and Si, respectively, in order to examine whether these rare-earth-lean materials are suitable for applications as permanent magnets. Structural and magnetic characterization of the family of alloys with the general formula Nd0.4 Zr0.6 Fe10-xCoxSi2(x = 0 -3) and their melt-spun ribbons were carried out using X-ray diffraction and M€ossbauer spectroscopy. The ThMn12-type structure is obtained for all samples as the majority phase with a minority a-Fe(CoSi) phase(less than 5 wt%) as it was estimated by XRd for x = 1 and 2. The Curie temperature increases linearly with Co substitution from 561 K for x = 0 to 712 K for x = 3. The saturation magnetization decreases slightly from 130.5(x =1)to 129.1 A·m2/kg(x=3), while the anisotropy field is following the same trend.

关键词： Permanent magnets X-ray diffraction M€ossbauer spectroscopy Rare-earth-lean magnetic materials Magnetic properties Melt-spun ribbons

Protective effects of d-002 on experimentally induced gastroesophageal reflux in rats

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World Journal of Gastroenterology 2014年第8期20卷 2085-2090页

作者： Zullyt zamora Vivian Molina Rosa Mas Yazmin Ravelo Yohany Perez Ambar Oyarzabal department of Pharmacology Centre of Natural ProductsNational Centre for Scientific ResearchHavana 10600Cuba

AIM: To investigate the effects of beeswax alcohols (d-002) on the esophageal damage induced by gastroesophageal reflux (GER) in rats.

关键词： d-002 Beeswax alcohols Esophagitis Gastroesophageal reflux Oxidative stress

Reversed-Phase HPLC Analysis of Steviol Glycosides Isolated from Stevia rebaudiana Bertoni

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Food and Nutrition Sciences 2014年第17期5卷 1711-1716页

作者： Venkata Sai Prakash Chaturvedula Julian zamora Natural Products Research Group Wisdom Natural Brands Gilbert USA

High Performance Liquid Chromatography (HPLC) experiments have been performed on nine steviol glycosides namely rebaudioside A, steviolbioside, stevioside, rubusoside, rebaudioside B, rebaudioside C, rebaudioside d, rebaudioside F, and dulcoside A isolated from the leaves of Stevia rebaudiana using Reversed-Phase (RP) column. Using RP-HPLC method, the individual retention times for nine naturally occurring ent-kaurane diterpene glycosides of S. rebaudiana reported in JECFA have been determined at four different temperatures: 20℃, 40℃, 60℃, and 79℃. Also, calculated the relative retention times of the eight steviol glycosides steviolbioside, stevioside, rubusoside, rebaudioside B, rebaudioside C, rebaudioside d, rebaudioside F, and dulcoside A against the major steviol glycoside rebaudioside A. HPLC results suggested that temperatures 40℃ and 60℃ would be ideal conditions for better separation of steviol glycosides.

关键词： Stevia rebaudiana Asteraceae diterpene Glycosides Reversed-Phase HPLC Analysis Retention and Relative Retention Times

Liver failure after an uncovered TIPS procedure associated with hepatic infarction

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World Journal of Hepatology 2010年第4期2卷 167-170页

作者： Eric López-Méndez daniel zamora-Valdés Mariana díaz-Zamudio Oscar F Fernández-díaz Lourdes ávila department of Gastroenterology National Institute of Medical Sciences and Nutrition Salvador Zubirán (INCMNSZ) Vasco de Quiroga 15 Zip Code 14000 Mexico City Mexico department of Surgery INCMNSZ Vasco de Quiroga 15 Zip Code 14000 Mexico City Mexico department of Radiology and Imaging INCMNSZ Vasco de Quiroga 15 Zip Code 14000 Mexico City Mexico

Transjugular intrahepatic portosystemic shunt (TIPS) is a safe and effective procedure for the treatment of complications of liver cirrhosis, such as refractory ascites, hepatic hydrothorax and refractory variceal bleeding. The aim of this paper is to describe a rare case of liver failure after a TIPS procedure. A 38-year-old diabetic male with Child-Pugh C liver cirrhosis due to chronic hepatitis C infection who had developed refractory ascites was scheduled for a TIPS procedure. Within 24 h following TIPS placement, the patient developed distributive shock, jaundice, persistentgrade 3 hepatic encephalopathy, severe coagulopathy andacute renal failure. He was treated with lactulose enemas, broad-spectrum antibiotics and blood-derived products. Laboratory data revealed a 100-fold increase in aminotransferases and a non-enhanced computed tomography showed an irregular hypodense area in the right posterior segment of the liver. despite being initially being in a stable condition, the patient developed progressive liver failure and died 2 mo later. Hepatic infarction is an uncommon phenomenon after a TIPS procedure; however, it can greatly complicate the course of a disease in a patient with an already compromised liver function.

关键词： Hepatic ischemia Ischemic hepatitis Liver infarc tion Transjugular intrahepatic portosystemic shunt Complications