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| 1 | Eucalyptus grandis plantations:effects of management on soil carbon,nutrient contents and yields显示文摘The expansion of fast-growing tree plantations is a worldwide process,with consequences on soil fertility and soil carbon storage.Disparate results were found on the effects of afforestation with Eucalyptus on soil carbon and other nutrient contents.These discrepancies are usually caused by differences in climate,land use history,soil texture as well as by management related factors such as plantation age,number of rotations,method of establishment(plantation or coppice),harvest residue management and soil preparation.We studied the effect of plantation age,number of rotations,and method of establishment on soils and plant nutrient concentrations in Eucalyptus grandis plantations in NE Argentina on different textured soils.We also determined if yields changed with nutrient variations in soils,and compared soils under plantations to soils under grasslands they replaced.Thirty-one E.grandis stands of different ages,number of rotations and method of establishment were evaluated as well as eight grassland sites.Levels of carbon,nitrogen,phosphorus,potassium,calcium and magnesium were determined for soils and plants.Soil carbon and nitrogen decreased over the number of rotations and were more pronounced in soils with 50-60%sand than soils with>75%sand.Coppice stands showed higher soil carbon and nitrogen levels than plantations,suggesting a negative effect of site preparation before planting on soil nutrient conservation,especially in fine-textured soils.Foliar nutrient concentrations did not follow the trends observed for soil nutrients nor did they reflect nutrient limitations.There was no evidence of decreased yields over successive rotations.Soil carbon and nitrogen contents decrease when grasslands are replaced by E.grandis plantations,and therefore a yield limitation may occur in a medium to long-term frame,especially in stands re-established for short-rotation management.Harvest residue management and site preparation must be specifically designed for improving soil nutrient management. | Diego Martin Sandoval Lopez Marcelo Fabian Arturi Juan Francisco Goya Carolina Alejandra Perez Jorge Luis Frangi | 2020 | Journal of Forestry Research2020，31，2： | 4 |
| 2 | Local predation pressure predicts the strength of mobbing responses in tropical birds显示文摘 | Luis SANDOVAL David R.WILSON | 2012 | Current Zoology2012，58，5： | 4 |
| 3 | Protein phosphatases and chromatin modifying complexes in the inflammatory cascade in acute pancreatitis显示文摘Acute pancreatitis is an inflammation of the pancreas that may lead to systemic inflammatory response syndrome and death due to multiple organ failure. Acinar cells, together with leukocytes, trigger the inflammatory cascade in response to local damage of the pancreas. Amplification of the inflammatory cascade requires up-regulation of proinflammatory cytokines and this process is mediated not only by nuclear factor κB but also by chromatinmodifying complexes and chromatin remodeling. Among the different families of histone acetyltransferases, the p300/CBP family seems to be particularly associated with the inflammatory process. cAMP activates gene expression via the cAMP-responsive element (CRE) and the transcription factor CRE-binding protein (CREB). CREB can be phosphorylated and activated by different kinases, such as protein kinase A and MAPK, and then it recruits the histone acetyltransferase co-activator CREB-binding protein (CBP) and its homologue p300. The recruitment of CBP/p300 and changes in the level of histone acetylation are required for transcription activation. Transcriptional repression is also a dynamic and essential mechanism of down-regulation of genes for resolution of inflammation, which seems to be mediated mainly by protein phosphatases (PP1, PP2A and MKP1) and histone deacetylases(HDACs) .Class HDACs are key transcriptional regulators whose activities are controlled via phosphorylationdependent nucleo/cytoplasmic shuttling. PP2A is responsible for dephosphorylation of class HDACs, triggeringnuclear localization and repression of target genes, whereas phosphorylation triggers cytoplasmic localization leading to activation of target genes. The potential benefit from treatment with phosphodiesterase inhibitors and histone deacetylase inhibitors is discussed. | Javier Escobar Javier Pereda Alessandro Arduini Juan Sastre Juan Sandoval Luis Aparisi Gerardo López-Rodas Luis Sabater | 2010 | World Journal of Gastrointestinal Pharmacology and Therapeutics2010，1，3： | 2 |
| 4 | Damage in hot rolling work rolls显示文摘 | Rafael Colás Jorge Ram??rez Ignacio Sandoval Julio C Morales Luis A Leduc | 1999 | Wear1999，，1： | 1 |
| 5 | Quercetin improves hepatic fibrosis reducing hepatic stellate cells and regulating pro‐fibrogenic/anti‐fibrogenic molecules balance显示文摘 | Luis Daniel Hernández‐Ortega Blanca Estela Alcántar‐Díaz Luis Alberto Ruiz‐Corro Ana Sandoval‐Rodriguez Miriam Bueno‐Topete Juan Armendariz‐Borunda Adriana María Salazar‐Montes | 2012 | J Gastroenterol Hepatol2012，，12： | 1 |
| 6 | Antioxidant activity of the cruciferous vegetable Maca ( Lepidium meyenii )显示文摘 | Manuel Sandoval Nataly N. Okuhama Fausto M. Angeles Vanessa V. Melchor Luis A. Condezo Juan Lao Mark J.S. Miller | 2002 | Food Chemistry2002，，2： | 1 |
| 7 | LASIK World Literature Review显示文摘 | Kerry D. Solomon Luis E. Fernández de Castro Helga P. Sandoval Joseph M. Biber Brian Groat Kristiana D. Neff Michelle S. Ying John W. French Eric D. Donnenfeld Richard L. Lindstrom | 2009 | Ophthalmology2009，，4： | 1 |
| 8 | Comparison of the incidence and visual significance of posterior capsule opacification between multifocal spherical, monofocal spherical, and monofocal aspheric intraocular lenses显示文摘 | Joseph M. Biber Helga P. Sandoval Rupal H. Trivedi Luis E. Fernández de Castro John W. French Kerry D. Solomon | 2009 | Journal of Cataract & Refractive Surgery2009，，7： | 1 |
| 9 | Solid–solid phase transitions in Fe?nanowires induced by axial strain显示文摘 | Luis Sandoval Herbert M Urbassek | 2009 | Nanotechnology2009，，32： | 1 |
| 10 | Refractive Surgery Survey 2004显示文摘 | Helga P. Sandoval Luis E. Fernández de Castro David T. Vroman Kerry D. Solomon | 2005 | Journal of Cataract & Refractive Surgery2005，，1： | 1 |
| 11 | Refractive surgery survey 2001显示文摘 | Kerry D Solomon Mike P Holzer Helga P Sandoval Luis G Vargas Liliana Werner David T Vroman Terrance J Kasper David J Apple | 2002 | Journal of Cataract & Refractive Surgery2002，，2： | 1 |
| 12 | Urbanization has opposite effects on the territory size of two passerine birds显示文摘Background:Urban expansion has been identified as one of the leading drivers of biodiversity change or loss.For birds,urbanization is specifically related to survival,breeding success,and territory size.Understanding how different birds adjust territory size in response to urbanization is essential for their conservation in urban environments and to better understand why some species are lost and others persist under this condition.We evaluated the effect of urbanization on the territory size of an urban avoider species,White-eared Ground-Sparrow(Melozone leucotis),and an urban adapter species,House Wren(Troglodytes aedon),at five Costa Rican sites.Methods:We measured the size of 30 ground-sparrow and 28 wren territories using a total of 296 h of observation.We followed each individual for at least 1 h per day for at least 2 days of two consecutive years,and geo-referenced their locations.Territory size was estimated using the minimum convex polygon method.We measured the urban surfaces(roads,buildings,any other paved area,soccer fields,lawns,and gardens with short grass)within territories.Results:Ground-sparrow territories were larger at the highly urbanized site than at the non-urbanized site.Wren territories were larger at the low urbanized site than at the highly urbanized site.We found a positive relationship between urban surface and territory size for the ground-sparrow,but not for the wren.Conclusions:Our results showed that not all birds adjust territory size in the same way in response to urbaniza-tion.We showed that urban avoiders probably need to defend larger territories in urban environments to find all the resources required to survive because urban environments may provide insufficient resources such as food or shelter.Urban adapters on the other hand defend smaller territories in urban environments because even small territories may provide sufficient resources.These results suggest specific behavioral adaptations developed by Neotropical birds inhabiting urban environments. | Roselvy Juárez Eduardo Chacón‑Madrigal Luis Sandoval | 2020 | Avian Research2020，11，2： | 1 |
| 13 | 论当代全球化显示文摘当代全球化始于20世纪70年代,建立在石油、内燃机、电等基础上,主要表现为一个世界经济下降趋势,同时也与世界工业重组、跨国公司生产重组、生产和金融极度合理化相伴随。美国股市泡沫、房地产泡沫、财政赤字等问题集中反映了当代全球化中的问题。未来时期可能会爆发严重世界经济危机,争霸战争、生态危机、以美元为基础的货币体系危机、对资本主义全球化的替代等也会出现。对当代全球化的研究,对我们正确认识当代资本主义,具有重要意义。 | Luis Sandoval Ramirez 傅泽风 | 2008 | 中共中央党校学报2008，12，5： | 0 |
| 14 | Regeneration of Plants from Embryogenic Cell Suspensions of cv.“Datil”(Musa AA):Morphological Evaluation of Plants in the Field显示文摘The full cycle from embryogenic callus(EC)induction to field evaluation of regenerated plants is reported for the first time for banana cv.“Datil”(Musa AA).Immature male flowers were used for EC induction on a modified M1 culture medium.The ideal type of EC was obtained in the presence of 4.5μM and 9.0μM 2,4-dichlorophenoxyacetic acid(2,4-D).Embryogenic cell suspensions were established in both concentrations of 2,4-D;however,only the suspensions from ideal callus(IC)formed with 4.5μM of 2,4-D were regenerated.A histological study revealed the formation of structurally different cell masses during the regeneration phase of cv.“Datil”.The embryos germination was characterized by the growth cellular aggregates,indicating the possible occurrence of secondary embryogenesis.Development and acclimatization of the plants were carried out in a normal manner as observed for other cultivars.Field evaluation of the plants’genetic stability was based on observation of morphological traits.In the vegetative growth phase,6.61%of the plants presented drooping leaves and deformed semi-limbs.These traits,however,did not affect further plant growth during flowering and harvest phases.The produced fruits were of good quality.And the present study indicates that this cultivar may be stable genetically. | Juan Luis Ortiz Vargas Jorge Sandoval Fernández María Elena Aguilar Vega | 2018 | Journal of Agricultural Science and Technology(B)2018，8，1： | 0 |
| 15 | Intruder familiarity and not duet similarity influences the territory defense in a year-round territorial bird species显示文摘To avoid unnecessary energy expenditures in territorial defense,many species(e.g.,insects,amphibians,birds,and mammals)have developed the capability to distinguish between different intruder types using visual,acoustic,and/or chemical signals.Determining the mechanism used for intruder recognition is key to understanding the dynamics of territorial behaviors.In birds that use vocalizations for territorial defense,the frequency and duration of vocalizations or the familiarity with the intruder may be the main mechanism used for intruder recognition.Here,we conducted a playback experiment with territorial White-eared Ground-sparrows(Melozone leucotis),to analyze if territorial pairs recognize intruders using frequency and duration characteristics(a bird’s response is based on how structurally similar the intruders’duets are to their own)or by familiarity with the intruders(neighbors vs.non-neighbors).We focused on duets because this species uses duets exclusively for territorial defense.We broadcasted a duet from a territorial neighbor,two duets from non-neighbors(with different frequency and duration characteristics),and a duet from a control species in 39 territorial pair from three populations.During playback we measured five behavioral responses:latency of the first vocalization,latency of the approach to the speaker,time spent close the speaker(within 5 m),number of individuals that approached the speaker,and the number of vocalizations.We found that territorial White-eared Ground-sparrow pairs responded stronger to neighbors than non-neighbors,and this response is not influenced by duet duration or frequency characteristics.This result suggests that neighbors represent a greater territorial threat for White-eared Ground-sparrows than non-neighbors.Further work is necessary to understand how common this observation is for tropical species that defend small territories year-round. | Tihana Hamzaj Brendan Graham Katherine Bonilla Ignacio Gutiérrez Luis Sandoval | 2022 | Avian Research2022，13，2： | 0 |
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