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Convergence in leaf phenology traits of two understorey ferns in the northwestern Iberian Peninsula

Journal of Plant Ecology 2018年第1期11卷 92-102页

作者： luis g.quintanilla Beatriz Pías Department of Biology and geology Physics and Inorganic ChemistrySchool of Environmental Sciences and TechnologyRey Juan Carlos Universityc/Tulipán s/n28933 MóstolesMóstolesSpain Department of Plant Sciences Faculty of BiologyComplutense of Madrid UniversityMadridSpain

Aims Plants control leaf phenology to maximize annual photosynthetic *** ferns play an important ecological role in many habitats,especially forests,their phenology traits have been poorly ***,we investigate the leaf phenology of two ferns of the forest understorey and analyse the relationship between the timing of leaf emergence and spore dispersal and the effect of between-year climatic *** We compared the leafing and sporing phenologies of two ferns with very large(>2 m),overwintering leaves:Culcita macrocarpa and Woodwardia *** regularly monitored individuals of six popu-lations in the northwestern Iberian Peninsula during a 3-year *** studied eight phenology variables:leafing start date,leafing end date,leaf expansion time,number of new leaves per individual,between-individual synchrony,within-individual synchrony,percentage of fertile leaves and spore release *** also determined leaf mass per area(LMA)and gathered data on air temperature and *** findings Both *** and *** produce few leaves(~2 leaves individual−1 year−1),which expand simultaneously for a very long period(from midwinter to early summer),are retained for more than 1 year(37 and 19 months,respectively)and have relatively high *** traits,together with large leaf size,have also been found in seed plants from the forest understorey and represent adap-tations to this light-limited *** of both study ferns are simultaneously released in late winter,with little between-year variation caused by differences in air *** remarkable similarity between species suggests that the convergence in tim-ing of leaf emergence favours the convergence in timing of spore dispersal.

关键词： Culcita macrocarpa leaf phenology spore dispersal temperate forest Woodwardia radicans

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Use of two-surfactants mixtures to attain specific HLB values for assisted TPH-diesel biodegradation

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Journal of Environmental Sciences 2004年第6期16卷 950-956页

作者： luis g. Torres Neftalí Rojas Rosario Iturbe Instituto de Ingeniería Universidad Nacional Autó noma de México Coordinación de Ingeniería Ambiental Grupo Saneamiento de Suelos y Acuíferos Apartado Postal 70-472 Coyoacán 04510 México D.F. Mexico

In a surfactant assisted biodegradation process, the choice of surfactant(s) is of crucial importance. The question is: does the type of surfactant(i.e. chemical family) affect the biodegradation process at fixed hidrophillic-lypofillic balance(HLB) values? Microcosm assessments were developed using contaminated soil, with around of 5000 mg/kg of hydrocarbons as TPH-diesel. Mixtures of three nonionic surfactants were employed to get a wide range of specific HLB values. Tween20 and Span20 were mixed in the appropriate proportions to get HLB values between 8.6 and 16.7. Tween/Span60 mixtures reached HLB values between 4.7 and 14.9. Finally, Tween/Span80 combinations yielded HLB values between 4.3 and 15. TPH-diesel biodegradation was measured at the beginning, and after 8 weeks, as well as the FCU/gr soil, as a measure of microorganisms′ development during the biodegradation period. A second aim of this work was to assess the use of guar gum as a biodegradation enhancer instead of synthetic products. The conclusions of this work are that surfactant chemical family, and not only the HLB value clearly affects the assisted biodegradation rate. Surfactant's synergism was clearly observed. Regarding the use of guar gum, no biodegradation enhancement was observed for the three assessed concentrations, i.e., 2, 20, and 200 mg/kg, respectively. On the contrary, TPH-diesel removal was lower as the gum concentration increased. It is quite possible that guar gum was used as a microbial substrate.

关键词： aged soils enhanced bioremediation HLB mixtures Tween Span surfactants

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How secure can we expect the surveillance policies to be after the implementation in T1 polyps with carcinoma?

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World Journal of gastrointestinal Endoscopy 2024年第9期16卷 502-508页

作者： Cristina Mateos Sanchez Elvira quintanilla Lazaro luis Ramon Rabago Department of gastroenterological Severo Ochoa HospitalMadridLeganes 28911Spain Department of gastroenterology San Rafael HospitalMadrid 28016Spain

Approximately 7%of the polyps resected endoscopically have an adenocarcinoma focus,with no previous endoscopic evidence of *** raises the question of whether endoscopic resection has been ***,there is no consensus on what the endoscopic and histological criteria for good prognosis are,the appropriate follow-up strategy and what are the long-term *** aim of the retrospective study by Fábián et al was to evaluate the occurrence of local relapse or distant metastasis in those tumors that were resected endoscopically compared to those that underwent oncologic *** concluded that,regardless of the treatment strategy chosen,there was a higher recurrence rate than described in the literature and that adherence to follow-up was *** management approach for an endoscopically benign polyp histologically confirmed as adenocarcinoma depends on the presence of any of the previously described poor prognostic histological *** none of these factors are present and the polyp has been completely resected en bloc(R0),active surveillance is considered appropriate as endoscopic resection is deemed *** results highlight,once again,the need for further multicentric clinical practice studies to obtain more evidence for the purpose of establishing appropriate treatment and follow-up strategies.

关键词： pT1 adenocarcinoma polyps pT1 follow up management Histological recurrence rate of pT1 adenocarcinoma Endoscopic and histologic poor prognostic criteria

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Reconstruction after pancreatoduodenectomy:Pancreatojejunostomy vs pancreatogastrostomy

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World Journal of gastrointestinal Oncology 2014年第9期6卷 369-376页

作者： Tatiana gómez Ana Palomares Mario Serradilla luis Tejedor Department of Surgery Hospital Punta de Europa Division of Hepato-Pancreatic-Biliary Surgery Department of SurgeryComplejo Hospitalario de Jaén

Pancreatic surgeons try to find the best technique for reconstruction after pancreatoduodenectomy(PD) in order to decrease postoperative complications,mainly pancreatic fistulas(PF).In this work,we compare the two most frequent techniques of reconstruction after PD,pancreatojejunostomy(PJ) and pancreatogastrostomy(Pg),in order to determine which of the two is better.A systematic review of the literature was performed,including major meta-analysis articles,clinical randomized trials,systematic reviews,and retrospective studies.A total of 64 articles were finally *** and Pg are usually responsible for most of the postoperative morbidity,mainly due to the onset of PF,being considered a major trigger of life-threatening complications such as intra-abdominal abscess and *** included systematic reviews reported a significant difference only in the incidence of intraabdominal collections favouring ***,delayed gastric emptying and mortality were not *** there was heterogeneity between these studies,all were conducted in specialized centers by highly experienced surgeons,and the surgical care was likely to be similar for all the *** disadvantages of Pg include an increased incidence of delayed gastric emptying and of main pancreatic duct obstruction due to overgrowth by the gastric *** function appears to be worse after Pg than after PJ,resulting in severe atrophic changes in the remnant *** on the type of PJ or Pg used,the PF rate and other complications can also be *** best method to deal with the pancreatic stump after PD remains *** choice of method of pancreatic anastomosis could be based on individual experience and on the surgeon's preference and adherence to basic principles such as good exposure and *** conclusion,up to now none of the techniques can be considered superior or be recommended as standard for reconstruction after PD.

关键词： Pancreatoduodenectomy Pancreatojeju-nostomy Pancreatogastrostomy Pancreatic fistula Pancreatic cancer Surgical technique

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The movement of ＂false antennae＂ in butterflies with ＂false head＂ wing patterns

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Current Zoology 2015年第4期61卷 758-764页

作者： Tania g. LOPEZ-PALAFOX Armando luis-MARTINEZ Carlos CORDERO Posgrado en Ciencias Biologicas Instituto de Ecologia Universidad Nacional Autonoma de Mexico Distrito Federal 04510 Mexico Museo de Zoologia Departamento de Biologia Evolutiva Facultad de Ciencias Universidad Nacional Autonoma de Mexico Distrito Federal 04510 Mexico Departamento de Ecologia Evolutiva Instituto de Ecologia Universidad Nacional Autonoma de M6xico Distrito Federal 04510 Mexico

In many butterfly species of the family Lycaenidae, the morphology and color pattern of the hind wings, together with certain behaviors, suggests the presence of a false head （FH） at the posterior end of the perching individual. This FH is consi- dered an adaptation to escape from visually oriented predators. A frequent component of the FH are the tails that presumably resemble the antennae, and the typical hind wings back-and-forth movement along the sagittal plane （HWM） performed while perching apparently move the tails in a way that mimics antennal movement. By exposing 33 individuals from 18 species of Lycaenidae to a stuffed insectivorous bird, we tested two alternative hypotheses regarding HWM. The first hypothesis proposes that, when the butterfly is observed at close range, the HWM distorts the shape of the false head thus reducing its deceiving effect and, therefore, selection will favor butterflies that stop moving their wings when a predator is close by; the second hypothesis says that an increase in the frequency of HWM improves its deflective effect when the butterfly confronts a predator at close range. Our results tend to support the second hypothesis because half of the butterflies started to move their hind wings or increased the rate of HWM when exposed to the stuffed bird; however a substantial proportion of butterflies （30%） stopped moving their hind wings or decreased the rate of HWM as expected from the first hypothesis. Our observations also showed that there is great variation in the rates of HWM, and demonstrated the existence of alternative ways of producing ＂vivid＂ movement of the hind wing tails （the ＂false antennae＂） in the absence of HWM [Current Zoology 61 （4）： 758-764, 2015].

关键词： Butterflies Lycaenidae Predator deception Anti-predator behavior Wing morphology

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Intraoperative ERCP:What role does it have in the era of laparoscopic cholecystectomy?

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World Journal of gastrointestinal Endoscopy 2011年第12期3卷 248-255页

作者： luis R Rábago Alejandro Ortega Inmaculada Chico David Collado Ana Olivares Jose luis Castro Elvira quintanilla Department of gastroenterology Severo Ochoa Hospital

In the treatment of patients with symptomatic cholelithiasis and choledocholithiasis (CBDS) detected during intraoperative cholangiography (IOC),or when the preoperative study of a patient at intermediate risk for CBDS cannot be completed due to the lack of imaging techniques required for confirmation,or if they are available and yield contradictory radiological and clinical results,patients can be treated using intraoperative endoscopic retrograde cholangiopancreatography (ERCP) during the laparoscopic treatment or postoperative ERCP if the IOC finds *** choice of treatment depends on the level of experience and availability of each option at each *** ERCP has the advantage of being a single-stage treatment and has a significant success rate,an easy learning curve,low morbidity involving a shorter hospital stay and lower costs than the two-stage treatments (postoperative and preoperative ERCP).Intraoperative ERCP is also a good salvage treatment when preoperative ERCP fails or when total laparoscopic management also fails.

关键词： Intraoperative endoscopic retrograde cholangiopancreatography Laparoendoscopic treatment Postoperative endoscopic retrograde cholangiopancreatography Rendezvous technique

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Relationship between Physical and Chemical Soil Attributes and Plant Species Diversity in Tropical Mountain Ecosystems from Brazil

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Journal of Mountain Science 2014年第4期11卷 875-883页

作者： Ferna de CARVALHO Edward luis gODOY Francy J. g. LISBOA Fatima Maria de Souza MOREIRA Francisco Adriano de SOUZA Ricardo luis Louro BERBARA g Wilson FERNES Laboratory of Evolutionary Ecology and Biodiversity Department of Geral Biology Institute of Biology Sciences Federal University of Minas Gerais Belo Horizonte MG 30161-901 P.O. Box 486 Brazil Department of Biology Microbiology and Biological Processes Department of Soil Science Federal University of LavrasLavras Minas Gerais 37200-000 P.O.Box 3037 Brazil Department of Biological Sciences Ferderal University of S?o Jo?o Del Rei S?o Jo?o del-Rei Minas Gerais 36307-352Brazil Laboratory of Soil Biology Department of Soil Science Federal Rural University of Rio de Janeiro Seropédica Rio de Janeiro 23890-000 Brazil Embrapa Maize and Sorghum Center for Applied Biology Rod. MG 424 KM 45 Caixa Postal Sete Lagoas Minas Gerais 35701-970 P.O. Box 285 Brazil

Although the high diversity of plant species in the rupestrian fields has been primarily attributed to the existence of a set of distinct habitats, few studies support this assertion. The present study aimed to further investigate the relationship between physical and chemical attributes of soils with the diversity of plant species in this unique ecosystem. The rupestrian field is a unique vegetation formation that covers some of the southeastern Brazilian mountains in the transition of the Atlantic rain forest and the Cerrado(savanna). Different habitats occur according to soil characteristics(e.g., presence of rocks, sand, fertility, hydrology, etc.). These attributes ultimately influence the vegetation that is highly adapted to the harsh edaphic and climatic mountain conditions. Five distinct habitats were studied by us: rocky outcrops, peat bogs, sandy bogs, quartz gravel fields, and "cerrado"(savanna). A floristic survey indicated that four families are found at greater frequency: Poaceae, Asteraceae, Cyperaceae, and Leguminosae. The greatest diversity of plant species was found in the rocky outcrops habitat, followed by cerrado, peat bog, quartz gravel grassland, and sandy bogs, respectively. The main difference in the floristic composition among these habitats was related to the dominant species. Trachypogon spicatus(Poaceae) was the most dominant species in the rocky outcrops, Axonopus siccus(Poaceae) in the peat bogs, Lagenocarpus rigidus(Cyperaceae) in the sandy bogs, Schizachyrium tenerum(Poaceae) in the cerrado, while Vellozia sp. 8(Velloziaceae) dominated the vegetation in the quartz gravel grassland. This study demonstrated that physical and chemical soil properties strongly related the diversity of plant species occurring in the different habitats of rupestrian fields.

关键词： Floristic diversity Plant-soilrelationships Espinhaqo Range Biodiversity Mountain ecology Plant habitat

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Ectopic papilla of Vater in the pylorus

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World Journal of gastroenterology 2009年第41期15卷 5221-5223页

作者： Iván guerra luis Ramón Rábago Fernando Bermejo Elvira quintanilla Silvia garcía-garzón gastroenterology Service University Hospital Severo Ochoa Leganés 28911 Madrid Spain

The major papilla of Vater is usually located in the second portion of the duodenum, to the posterior medial wall. Sometimes the mouth of the biliary duct is located in other areas. Drainage of the common bile duct into the pylorus is extremely rare. A 73-year old man, with a history of duodenal ulcer, was admitted to hospital with the diagnosis of cholangitis. Dilatation of the extrahepatic biliary duct was observed by abdominal ultrasonography, and endoscopic retrograde cholangiopancreatography （ERCP） was performed. No area suggesting the presence of the papilla of Vater was found within the second duodenal portion. Finally the major papilla was located in the theoretical pyloric duct. Cholangiography was performed and choledocholithiasis was found in the biliary tree. The patient underwent dilatation of the papilla with a balloon tyre and removal of a 7 mm stone using a Dormia basket, which solved the problem without further complications. This anomaly increased the difficulty of performing therapeutic interventions during ERCR This alteration in anatomy may increase the risk of complications during papillotomy, with a theoretically higher risk of perforation. Dilatation using a balloon was the chosen therapeutic technique both in our case and in the literature, due to its low rate of complications.

关键词： Ectopic common bile duct Endoscopic dilatation Endoscopic retrograde cholangiopancreatog- raphy Papilla of Vater Papillotomy Pyloric drainage

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Erythropoietin modulates bone marrow stromal cell differentiation

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Bone Research 2019年第3期7卷 272-285页

作者： Sukanya Suresh luis Fernandez de Castro Soumyadeep Dey Pamela g. Robey Constance Tom Noguchi Molecular Medicine Branch National Institute of Diabetes and Digestive and Kidney Diseases National Institutes of Health Bethesda MD 20892 USA Skeletal Biology Section National Institute of Dental and Craniofacial Research National Institutes of Health Bethesda MD 20892 USA

Erythropoietin is essential for bone marrow erythropoiesis and erythropoietin receptor on non-erythroid cells including bone marrow stromal cells suggests systemic effects of erythropoietin. Tg6 mice with chronic erythropoietin overexpression have a high hematocrit, reduced trabecular and cortical bone and bone marrow adipocytes, and decreased bone morphogenic protein 2 driven ectopic bone and adipocyte formation. Erythropoietin treatment(1 200 IU·kg–1) for 10 days similarly exhibit increased hematocrit,reduced bone and bone marrow adipocytes without increased osteoclasts, and reduced bone morphogenic protein signaling in the bone marrow. Interestingly, endogenous erythropoietin is required for normal differentiation of bone marrow stromal cells to osteoblasts and bone marrow adipocytes.ΔEpoR_E mice with erythroid restricted erythropoietin receptor exhibit reduced trabecular bone, increased bone marrow adipocytes, and decreased bone morphogenic protein 2 ectopic bone formation. Erythropoietin treated ΔEpoR_E mice achieved hematocrit similar to wild-type mice without reduced bone, suggesting that bone reduction with erythropoietin treatment is associated with non-erythropoietic erythropoietin response. Bone marrow stromal cells from wild-type,Tg6, and ΔEpoR_E-mice were transplanted into immunodeficient mice to assess development into a bone/marrow organ. Like endogenous bone formation, Tg6 bone marrow cells exhibited reduced differentiation to bone and adipocytes indicating that high erythropoietin inhibits osteogenesis and adipogenesis, while ΔEpoR_E bone marrow cells formed ectopic bones with reduced trabecular regions and increased adipocytes, indicating that loss of erythropoietin signaling favors adipogenesis at the expense of osteogenesis. In summary, endogenous erythropoietin signaling regulates bone marrow stromal cell fate and aberrant erythropoietin levels result in their impaired differentiation.

关键词： bone marrow adipocyte normal differentiation

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Identification of tree groups used by secondary cavity-nesting birds to simplify forest management in subtropical forests

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Journal of Forestry Research 2020年第4期31卷 1417-1424页

作者： Alejandro A.Schaaf Román A.Ruggera Ever Tallei Constanza g.Vivanco luis Rivera Natalia Politi Instituto de Ecorregiones Andinas(INECOA) Universidad Nacional de Jujuy–Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Av.Bolivia 12394600 San Salvador de JujuyJujuyArgentina Fundación CEBio Roca 444600 San Salvador de JujuyJujuyArgentina

In tropical and subtropical forest ecosystems,cavities formed by decay processes are a key but scarce resource for birds that nest and roost in them,which makes them a highly sensitive group to *** piedmont forest of northwestern Argentina is a complex ecosystem with 113 tree and 120 bird *** has high logging pressure on the few,well-conserved forest remnants,complicating the delineation of sustainable management guidelines for each tree or bird species in a short *** objective was to reduce the complexity of subtropical forests by grouping tree species according to the characteristics used by secondary cavity-nesting birds(*** excavators).In the piedmont forest,50 plots of 0.25 ha were sampled to record cavity trees and cavity *** were then used in a cluster analysis to form tree ***,cavities were searched to identify the bird species using the decay-formed cavities.A total of 187 cavity trees,comprising 23 tree species,were recorded,and these formed four tree groups or *** recorded 86 cavities that were used by secondary cavitynesting bird *** four tree groups were unequally used by secondary cavity *** tree group that included valuable timber species(Myroxylon peruiferum,Anadenanthera colubrina and Calycophyllum multiflorum)and had the greatest cavity availability represented 71%of total cavity *** tree group with valuable timber species(Cedrela balansae and Amburana cearensis),measured>73 cm DBH and>21 m tall,had cavity entrances>0.10 cm2,and contributed 14%of all cavity use by birds.A third group had no highly economically valuable tree species,and included the snag category(*** dead trees)as well as a 15%of cavity *** fourth tree group had a DBHghly economically valuable tree species(Cordia trichotoma),and supported no cavity *** clustering of subtropical trees can reduce the complexity of these forests,hence easing their management by

关键词： Biodiversity Cavity-nesting birds Conservation Logging

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