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Soil seed bank assembly following secondary succession on abandoned agricultural fields in nicaragua

Journal of Forestry Research 2009年第4期20卷 349-354,I0006页

作者： Benigno González-Rivas Mulualem Tigabu guillermo castro-marín Per Christer Odén Facultad de Recursos naturales y del Ambiente. Universidad nacional Agraria. Managua Swedish University of Agricultural Sciences Faculty of Forest Sciences Southern Swedish Forest Research Centre Sweden.

The composition and density of seeds in soils of secondary forests derived on abandoned fields after 4, 9 and 14 years of aban- donment were quantified to examine whether the soil seed bank assembles during secondary succession as the plant communities assemble. A total of 18, 37 and 48 soil samples from 4-, 9- and 14-year old sites, respectively were collected in 15 cm × 15 cm plots up to 9 cm depth. A total of 3, 5 and 9 species were found on sites abandoned 4, 9 and 14 years ago, respectively, Among different life forms, trees were highly represented in the soil seed bank of 9-year （60%） and 14-year （33%） old sites compared to 4-year old site entirely dominated by non- woody flora. The total number of seeds ranged from 327 in the 4-year old site to 146 in the 14-year old site, and the corresponding density of viable seeds ranged from 141 seeds m^-2 in the 4- year old site to 26 seeds m^-2 in the 14-year old site with a consistent decreasing pattern in the chronosequence. The similarity between the soil seed flora and the standing woody vegetation was low for both 9- and 14-year old sites while complete dissimilarity was found for 4-year old site. We concluded that the species composition of soil seed banks assemble gradually during secondary succession, but the overall seed density is still low for natural regeneration of trees to rely on. To expedite the recovery of secondary forests on such abandoned fields, the seed bank needs to be supplemented by direct seeding, enrichment planting of desired species and installing artificial perches for facilitating seed dispersal.

关键词： seed dispersal dry forest seed bank secondary succession restoration nicaragua

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A chronosequence analysis of forest recovery on abandoned agricultural fields in nicaragua

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Journal of Forestry Research 2009年第3期20卷 213-222,286页

作者： guillermo castro marín Mulualem Tigabu Benigno González-Rivas Per Christer Odén Facultad de Recursos naturales y del Ambiente Universidad Nacional Agraria Swedish University of Agricultural Sciences Faculty of Forest Sciences Southern Swedish Forest Research Centre Tropical Silviculture and Seed Laboratory

Species composition, diversity and population structure of woody species recovered on three abandoned agricultural fields after 4, 9 and 14 years were characterized. Seedlings, saplings/poles and mature trees were identified and counted in 70 plots of 100 m2 in each abandoned site. A total of 13, 29 and 22 families represented by 17, 48 and 44 species were registered in 4-, 9-and 14-year-old stands, respectively. There was a shift in dominant species across successional stages. Lonchocarpus acuminatus had the highest importance value in the 4-year old stand, whereas, Myrospermun frutescens, Guazuma ulmifolia and Cordia alliodora had the highest importance value in the 9-year-old-stand and Caesaeria corymbosa, Muntingia calabura, Gliricidia sepium and Tabebuia rosea in the 14-year-old stand. The total stem density increased from 5011 to 9631 individuals per hectare as the age of abandonment increased from 4 to 14 years. The total basal area of individuals ≥ 1cm d.b.h. also increased with the age of abandonment. Overall, small individuals (ntributed to more than half of the total basal area. Species diversity was the highest in the 9-year old stand followed by 14-and 4-year-old stands. We concluded that floristic composition of secondary forests recovers rapidly to the mature forest level compared to structural attributes, which is consistent with the general successional trajectories of tropical dry forest.

关键词： Central America dry forest neotropics restoration secondary succession abandoned agricultural field forest recovery

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Changes in iron transporter divalent metal transporter 1 in proximal jejunum after gastric bypass

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World Journal of Gastroenterology 2014年第21期20卷 6534-6540页

作者： Andrés marambio guillermo Watkins Fabiola castro Andrea Riffo Roberta Zú?iga Jaime Jans maría E Villanueva guillermo Díaz Department of Surgery University of Chile Clinical HospitalSantiago 8380456Chile Department of Gastroenterology Chilean Air Force Clinical HospitalSantiago 7560171Chile Department of Pharmacological and Toxicological Chemistry University of Chile Chemistry and Pharmacy FacultySantiago 8380492Chile Pathology Service University of Chile Clinical HospitalSantiago 8380456Chile

AIM: To describe the variation that divalent metal transporter 1 (DMT1) shows in patients after Roux-en-Y gastric bypass (RYGB) surgery.

关键词： Roux-en-Y gastric bypass Bariatric surgery Divalent metal transporter 1 Anaemia Iron

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Fagus sylvatica and Quercus pyrenaica:Two neighbors with few things in common

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Forest Ecosystems 2023年第2期10卷 162-175页

作者： Sergio de Tomás marín Jesús Rodríguez-Calcerrada Salvador Arenas-castro Iván Prieto guillermo González Luis Gil Enrique G.de la Riva Department of Ecology Brandenburgische Technische Universität Cottbus-SenftenbergKonrad-Wachsmann-Allee 603046CottbusGermany Forest Genetics and Ecophysiology Research Group School of Forestry EngineeringUniversidad Politécnica de MadridMadridSpain Area of Ecology Botany DepartmentEcology and Plant PhysiologyFaculty of SciencesUniversidad de CórdobaCórdobaSpain Ecology Department Faculty of Biology and Environmental SciencesUniversidad de LeónLeónSpain

Background:The Iberian Peninsula comprises one of the largest boundaries between Mediterranean and Eurosiberian vegetation,known as sub-Mediterranean *** ecotone hosts many unique plant species and communities and constitutes the low-latitude(warm)margin of numerous central European species which co-occur with Mediterranean *** of the main species found in this region are the Eurosiberian European beech(Fagus sylvatica L.)and the Mediterranean Pyrenean oak(Quercus pyrenaica Willd.).It remains unclear how the different physiological and adaptive strategies of these two species reflect their niche partitioning within a subMediterranean community and to what extent phenotypic variation(intraspecific variability)is driving niche partitioning across Eurosiberian and Mediterranean ***:We quantified functional niche partitioning,based on the n-dimensional hypervolume to nine traits related to resource acquisition strategies(leaf,stem and root)plus relative growth rate as an additional wholeplant trait,and the environmental niche similarity between Pyrenean oak and European ***,we analyzed the degree of phenotypic variation of both target species and its relationship with relative growth rates(RGR)and environmental *** recruitment was measured for both target species as a proxy for the average ***:Species’functional space was highly segregated(13.09%overlap),mainly due to differences in niche breadth(59.7%)rather than niche replacement(25.6%),and beech showed higher trait variability,i.e.,had larger functional ***,both species shared the environmental space,i.e.,environmental niches were *** plant traits were not related to abiotic variables or RGR,neither did RGR to plant ***:Both target species share similar environmental space,however,show notably different functional resource-use strategies,promoting a high complementarity that contributes to maintaining a high functiona

关键词： Environmental niche European beech Forest dynamics Functional niche Hypervolume Pyrenean oak Species coexistence Sub-Mediterranean community

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Seed germination and seedling establishment of neotropical dry forest species in response to temperature and light conditions

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Journal of Forestry Research 2009年第A2期20卷 99-104,I0001页

作者： Benigno Gonzalez-Rivas Mulualem Tigabu guillermo castro-marin Per Christer Oden Facultad de Recursos naturales y del Ambiente. Universidad nacional Agraria. Managua Nicaragua. Apartado Postal 453 Swedish University of Agricultural Sciences Southern Swedish Forest Research Centre PO Box 101 SE-230 53Alnarp Sweden

A study was conducted to examine the germination requirements of Cedrela odorata, Guaiacum sanctum and Calycophyllum candidissimum seeds, and the effect of light intensity on survival and growth of C. odorata and G. sanctum seedlings planted on open, partially-open and beneath the canopy of a dry forest in nicaragua. The results show that germination of C. candidissimum seeds was signifi- cantly higher in light than darkness at constant temperatures ranging from 20-35℃. Both C. odorata and G. sanctum seeds germinated in light and darkness to a varying extent, and the optimal germination temperature was around 20-25℃. Alternating temperature regimes did not improve germination. Survival of G. sanctum seedlings was 70% beneath the canopy and 80% in the open, and its relative growth rate in collar diameter was 1.88 mm/month in the open and 1.42 mm/month in the understory. Survival was generally poor for C. odorata, particularly in the understory. We concluded that light is an absolute requirement for the germination of C. candidissimum seeds while germination of C. odorata and G. sanctum seeds are more sensitive to temperature. Owing to its high survival rate on open site, G. sanctum could serve as a candidate species for reforestation of degraded sites.

关键词： canopy cover seed germination nicaragua photoblastic seed survival rate restoration Cedrela odorata Guaiacum sanctum Calycophyllum candidissimum

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natural regeneration dynamics of three dry deciduous forest species in Chacocente Wildlife Reserve, nicaragua

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Journal of Forestry Research 2009年第1期20卷 1-6页

作者： guillermo castro marin Mulualem Tigabu Benigno Gonzalez Rivas Per Christer Oden Facultad de Recursos naturales y del Ambiente Universidad Nacional Agraria Apartado posta 453 Managua Nicaragua Swedish University of Agricultural Sciences Faculty of Forest Sciences Department of Forest Genetics and Plant Physiology Tropical Silviculture and Seed Laboratory SE-901 83 Umea Sweden

A study was conducted to examine the natural regeneration of three dry forest species, Lysiloma divaricatum （Jacq.）, Tabebuia ochracea （Cham.） and Lonchocarpus minimiflorus （Donn. Sin.） over a three-year period and to analyze heterogeneity of regeneration in relationship to topographic slope and incidence of light in Chacocente Wildlife Reserve in nicaragua. Permanent sample plots were established in 2001, and all individuals with height as low as 10 cm and diameter as large as 10 cm were recorded for three consecutive years from 2001 to 2003. The results show that the density of naturally regenerated individuals varied significantly among species, as well as over time. L. minimiflorus and T. ochracea had higher densities compared with L. divaricatum, and the net change in population density was slightly positive for T. ochracea only. Regeneration was more abundant in the gentle and steep slopes under partial exposure of the crown to sunlight, thus resulting in aggregated pattern of distribution, especially for L. minimiflorus and T. ochracea. We concluded that natural regeneration alone is not sufficient to maintain the desired number of stocks of these species, and an immediate restoration measure should be taken to assist the natural regeneration process.

关键词： Central America mortality regeneration niche spatial pattern dry forest

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First histopathological study in kidneys of rodents naturally infected with Leptospira pathogenic species from Yucatan, Mexico

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Asian Pacific Journal of Tropical Medicine 2016年第2期9卷 140-142页

作者： marco Torres-castro Leonardo guillermo-Cordero Silvia Hernández-Betancourt Edwin Gutiérrez-Ruíz Piedad Agudelo-Flórez Ronald Peláez-Sánchez Jorge Zavala-castro Fernando I.Puerto Centro de Investigaciones Regionales ‘Dr.Hideyo noguchi' Universidad Autónoma de Yucatán Campus de Ciencias Biológicas y Agropecuarias Universidad Autónoma de Yucatán Facultad de Medicina Universidad CES

Objective: To report the renal histological lesions in synanthropic rodents, Mus musculus and Rattus rattus, naturally infected with Leptospira spp., captured in a rural community in Yucatan, Mexico. Methods: Kidney samples of synanthropic rodents were collected from a rural community in Yucatan, Mexico. Polymerase chain reaction was used to detect Leptospira spp. infection. Tissue kidney was fixed in 10% buffered formalin, processed according to the usual techniques for paraffin inclusion, cut and stained with hematoxylin and eosin, and examined using a conventional electronic microscope. Results: A total of 187 rodents were captured. nine individuals(4.8%) were positive for Leptospira spp. in the molecular analysis. All renal lesions observed in the histopathological study had been reported previously for Leptospira spp. infection. Conclusions: The histopathological lesions are present in the kidneys, plus the results of the polymerase chain reaction confirm that these rodents are true carriers of Leptospira spp.

关键词： Leptospira spp. Renal histopathological lesions Mus musculus Rattus rattus

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Polyphenolic content, in vitro antioxidant activity and chemical composition of extract from nephelium lappaceum L.(Mexican rambutan) husk

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Asian Pacific Journal of Tropical Medicine 2017年第12期10卷 1201-1205页

作者： Cristian Hernández Juan Ascacio-Valdés Heliodoro De la Garza Jorge Wong-Paz Cristóbal noé Aguilar guillermo Cristian martínez- ávila Cecilia castro-López Antonio Aguilera-Carbó Department of Animal nutrition Universidad Autónoma Agraria Antonio NarroCol. BuenavistaCalzada Antonio Narro No. 1923Saltillo25315CoahuilaMexico Food Research Department School of ChemistryUniversidad Autónoma de CoahuilaBlvd. Venustiano CarranzaCol. RepúblicaSaltillo25280CoahuilaMexico Chemistry and Biochemistry Laboratory Faculty of AgronomyUniversidad Autónoma de Nuevo LeónFrancisco I. Madero S/NHacienda el Canada66050General EscobedoNLMexico

Objective: To determinate the recovery of total polyphenolic compounds content,in vitro antioxidant activity and HPLC/ESI/MS characterization of extract from nephelium lappaceum L.(Mexican rambutan).Methods: The rambutan husk extract was obtained by aqueous extraction and a polyphenolic fraction was recovered using Amberlite XAD-16. The total polyphenolic compounds content was determined by the Folin Ciocalteu and butanol-HCI *** vitro antioxidant activity was performed using ABTS and ferric reducing antioxidant power ***: Mexican rambutan husk showed a total polyphenolic content of 582 mg/g and an evident antioxidant activity by ABTS and ferric reducing antioxidant power *** HPLC/ESI/MS assay allowed the identification of 13 compounds, most of which belong to ellagitannins. Geraniin, corilagin and ellagic acid were present in the sample;the mineral composition was also ***: Rambutan husk cultivated in Mexico is a promising source for the recovery of added value bioactive compounds with antioxidant activity, which have potential applications as bioactive antioxidant agents for the treatment of diseases.

关键词： Mexican rambutan Polyphenolic compounds Ellagitannins HPLC/ESI/MS

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Diabetes, Allopathic and Alternative Methods (Kombucha) for Its Treatment

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Journal of Diabetes Mellitus 2022年第4期12卷 187-203页

作者： guillermo nolasco-Rodríguez Laura Esmeralda Ordaz-castro Esther Albarrán-Rodríguez Lucia García-Delgado Jacinto Bañuelos-Pineda Manuel Rosales-Cortés Department of Veterinary Medicine University Science Center Biological and Agricultural Zapopan Mexico

Introduction: Diabetes is a disease characterized by an increase in blood glucose due to disorders in insulin production, this disease is widely distributed throughout the world. Objective: to review and systematize the general information on diabetes, as well as the traditional treatments and the findings on kombucha as an alternative method. Method: the information retrieval technique or literature review was used on the topics of diabetes, allopathic methods, kombucha, preparation procedures, chemical and microbiological components and pharmacological effects of the drink. Results: Various sources of information were found that explain the definition of diabetes and its classification. it commonly presents in four ways depending on the signs, the common ones being type 1, associated with destruction of the β cells of the pancreas and mainly affects minors, and type 2, which is related to genetic and environmental problems and It affects people over 18 years of age, and less frequently gestational diabetes and MODY type. Traditional drugs such as sulfonylureas, glinides and biguanides, thiazolidinediones and α-glucosidase inhibitors are used to control this disease, or alternative therapies are used such as kombucha, a fermented beverage that has its origins in China and is spread worldwide by its beneficial effects in chronic degenerative diseases such as diabetes, due to its chemical and microbiological content. Conclusion: The information establishes important data on kombucha as one of the complementary alternatives for the treatment of diabetes.

关键词： Diabetes Mellitus Alternative Medicine Kombucha Traditional Medicine Pathophysiology of Diabetes

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西班牙某医院波及黄斑的视网膜脱离患者手术时机与术后视力的关系（英文）

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国际眼科杂志 2017年第12期17卷 2203-2206页

作者： Raquel castro-Florez R Isabel Gese-Bordils Mercedes Garcia-Torre Ignacio Jimenez-Alfaro guillermo Fernandez-Sanz fundacion jimenez diaz 视网膜科西班牙马德里28040

目的:分析西班牙某三级医院视网膜科接受手术治疗的黄斑裂孔性视网膜脱离患者。着重强调诊断与手术之间的时间间隔,试图寻找术前时间与视力下降之间的关系。方法:回顾性研究。包括77例在Universitario Fundación Jiménez Díaz医院接... 详细信息

目的:分析西班牙某三级医院视网膜科接受手术治疗的黄斑裂孔性视网膜脱离患者。着重强调诊断与手术之间的时间间隔,试图寻找术前时间与视力下降之间的关系。方法:回顾性研究。包括77例在Universitario Fundación Jiménez Díaz医院接受手术治疗的黄斑裂孔性视网膜脱离患者。结果:77例患者中有72例(72眼)参与了该研究。初步手术成功率为94.44%(68/72),采取1或2次干预措施后,全部患者成功率为98.61%(71/72)。术前平均时间为5.3±2.26d。7(9.72%)例患者视力下降2行或更多。视力下降与患者年龄之间具有统计学意义(P=0.001)。研究表明进一步手术干预使视网膜再次附着与视力下降检测之间存在相关联系(P=0.045)。而研究未能发现视力下降与术前时间(P=0.100),手术类型(P=0.578)或晶状体状态(P=0.413)之间具有统计学意义。结论:每家医院都应该研究治疗此类型视网膜脱离治疗的方式,以优化利用现有资源,确保最佳的解剖结构复位和功能恢复。

关键词：视网膜脱离黄斑手术结果视力下降

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