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Changes in Olsen P in Relation to P Balance in Contrasting Agricultural Soils

Pedosphere 2016年第5期26卷 636-642页

作者： Isabel DIAZ jose TOrrENT Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos Escuela Tdcnica Superior de Ingeniería Agronómica(ETSIA)Universidad de SevillaCtra de Utrera km 141013 Sevilla(Spain) Departamento de Agronomia Universidad de CordobaEdificio C4Campus de Rabanales14071 Cordoba(Spain)

Maintaining soil phosphorus(P) at adequate levels for plant growth requires assessing how the long-term P balance(viz., the difference between P inputs and outputs) results in changes in soil test P. The hypothesis that routinely measured soil properties can help predict the conversion factor of P balance into Olsen P was tested at 39 sites in agricultural areas of the Mediterranean region in Spain. A set of soil samples from each site was analyzed for Olsen P, inorganic P(P extracted using 0.5 mol L^(-1) H_2SO_4), pseudototal P(P extracted using 0.5 mol L^(-1) H_2SO_4 following ignition at 550℃), and organic P(the difference between pseudototal P and inorganic P). Organic and Olsen P were uncorrelated in most of the 39 soil sets, which suggests that organic P content changed little with P inputs and outputs. The slopes of the regression lines of Olsen P against pseudototal and inorganic P, which were used as two different measures of the conversion factor, ranged widely(from 0.03 to 0.25 approximately), with their average values(about 0.10) being similar to those found in long-term experiments conducted in temperate areas. Neither conversion factor was significantly correlated with any routinely measured soil property; however, the conversion factor for inorganic P was significantly lower for calcareous soils than for noncalcareous soils. Our negative results suggest the need to isolate the influence of soil properties from that of management systems and environmental factors relating to P dynamics in future studies.

关键词：磷素平衡农业土壤 H2SO4 土壤性质土壤测试转换因子常规测量石灰性土壤

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Chromium Adsorption in Different Mineralogical Fractions from Subtropical Soils

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Pedosphere 2017年第1期27卷 106-111页

作者： Jovana BAVARESCO Jesse R. FINK Maria Lucia K. RODRIGUES Clesio GIANELLO Vidal BARRON jose TOrrENT Department of Soils Federal University of Rio Grande do Sul 91540-000 Porto Alegre Rio Grande do Sul (Brazil) Laboratory of Soils Federal Institute of Parand 85555-000 Palmas Parand (Brazil) Department of Research and Laboratory Environmental Protection Foundation of Rio Grande do Sul State 90620-090 Porto AlegreRio Grande do Sul (Brazil) Department of Agronomy University of Cdrdoba C4 Building Campus of Rabanales 14071 C6rdoba (Spain)

Safe application of chromium(Cr)-containing organic industrial wastes to soil requires considering the ability of the soil to adsorb Cr.In this study,the maximum Cr adsorption capacity was assessed for the bulk samples and their clay and iron-free clay fractions of four subtropical soils differing in mineralogy.To this end,the samples were supplied with Cr(III) nitrate solutions at pH 4.5 or5.5.The results of Cr(III) adsorption fitted to a Freundlich equation and the adsorption capacity was positively correlated with soil organic matter and iron oxide contents.The clay fractions adsorbed more Cr per unit mass than the bulk soils and the iron-free clay fractions.The Cr(III) adsorption capacity increased with increasing soil pH due to more charges on adsorbing surfaces.Our results suggest that the soils rich in organic matter and iron oxides and having a pH above 4.5 are suitable for application of Cr(III)-loaded industrial wastes.

关键词：亚热带土壤吸附量中铬矿物成分 Freundlich方程 Cr(Ⅲ) 土壤有机质铁氧化物

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Magnetic discrimination between Al-substituted hematites synthesized by hydrothermal and thermal dehydration methods and its geological significance

Magnetic discrimination between Al-substituted hematites syn...

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中国科学院地质与地球物理研究所2012年度（第12届）...

作者： Zhaoxia Jiang Qingsong Liu Vidal Barron jose TOrrENT Yongjae Yu State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences Graduate School of the Chinese Academy of Sciences Departamento de Agronomia Universidad de Cordoba Department of Geology and Earth Environmental Sciences Chungnam National University

[1]Hematite,a ubiquitous mineral in aerobic sediments and soils of temperate and warm areas,is weakly magnetic.However,it carries a stable natural remanent magnetization,and thus can reflect paleoenvironment changes.To quantify the influence of Al content in hematite on its magnetic properties,two series of hematite particles were prepared by hydrothermal transformation of fenrihydrite in aqueous suspension(HFh* series) and by

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Quantification of Al-goethite from diffuse reflectance spectroscopy and magnetic methods

Quantification of Al-goethite from diffuse reflectance spect...

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中国科学院地质与地球物理研究所2014年度（第14届）学术年会

作者： Zhaoxia Jiang Qingsong Liu Claudio Colombo Vidal Barron jose TOrrENT Pengxiang Hu StateKeyLaboratoryofLithosphericEvolution InstituteofGeologyandGeophysicsChineseAcademyofSciences UniversityoftheChineseAcademyofSciences UniversitadelMoliseDip.diAgricoltura AlimentazioneedAmbientev.DeSanctisI-86100Campobasso(CB)Italy DepartamentodeAgronom?a UniversidaddeCordobaEdificioC4CampusdeRabanalesE-14071CordobaSpain

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Quantification of Al-goethite from diffuse reflectance spectroscopy and magnetic methods

Quantification of Al-goethite from diffuse reflectance spect...

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中国科学院地质与地球物理研究所2014年度（第14届）...

作者： Zhaoxia Jiang Qingsong Liu Claudio Colombo Vidal Barron jose TOrrENT Pengxiang Hu State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences University of the Chinese Academy of Sciences Universita del Molise Dip.di Agricoltura Alimentazione ed Ambientev.De SanctisI-86100 Campobasso (CB)Italy Departamento de Agronom?a Universidad de CordobaEdificio C4Campus de RabanalesE-14071 CordobaSpain

As one of the most abundant iron oxides in soils, the presence and nature of goethite is controlled by the soil conditions and burial history. The visible diffuse reflectance spectroscopy(DRS) is a useful tool for quantifying goethite. However, aluminium(Al) substitution for goethite is very common in soils and the effects of Al content on the DRS properties of goethite have not been fully resolved. In this study, two series of Al substituted goethites(Al-goethite) and 20 Chinese loess/palaeosol samples were investigated using both DRS and magnetic methods to test the feasibility of quantifying Al-goethite with the DRS method.Results show that the peak positions and amplitudes of the goethite DRS band are significantly influenced by Al substitution. Specifically, the goethite concentration proxy, the amplitude of the DRS band, is relatively stable only when Al substitution ranged between about 4 and16 mol per cent. Practically, in order to resolve the difficulty in measuring Al content in natural samples, the unblocking temperature(T b) is proposed as the proxy for Al substitution of goethite. When T b of Al-goethite was above 250 K, the amplitude of DRS can be used to reliably trace the goethite concentration variation in natural samples. For example, the DRS spectra for the Chinese loess–palaeosol samples support the idea that only haematite is enhanced via pedogenesis. In contrast, the origin of goethite seems to be mostly related to the aeolian inputs.

关键词： Environmental magnetism Magnetic mineralogy and petrology Rock and mineral magnetism

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Ferro and antiferromagnetism of ultrafine-grained hematite

Ferro and antiferromagnetism of ultrafine-grained hematite

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中国科学院地质与地球物理研究所2014年度（第14届）...

作者： Zhaoxia Jiang Qingsong Liu Mark J.Dekkers Claudio Colombo Yongjae Yu Vidal Barr on jose TOrrENT State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences University of the Chinese Academy of Sciences Paleomagnetic Laboratory ‘‘Fort Hoofddijk ’’Department of Earth SciencesFaculty of GeosciencesUtrecht University Dipartimento Agricoltura Ambiente Alimenti (Di AAA) Universit a del Molise Department of Geology and Earth Environmental Sciences Chungnam National University Departamento de Agronom?a Universidad de Cordoba

Aluminum-substituted hematite(here referred to as Al-Hm) is an important magnetic mineral for paleo and environmental magnetism. However, the magnetic properties of nanosized Al-Hm are poorly known. In this study, a series of Al-Hm samples(fourteen samples) and their nonsubstituted counterparts(referred to as pure-Hm)(seven samples) were synthesized with particle sizes ranging from 14 to 124 nm.With decreasing particle size, coercive force(B c), magnetic remanence(M r) acquired in a 5 T field at room temperature, and the maximum blocking temperature(T b) of Al-Hm descend gradually;T b drops abruptly from 800 to 200 K at 17.2 6 3.7 nm. This size defines the superparamagnetic(SP)/single-domain(SD) threshold of Al-Hm which is significantly lower than that of pure-Hm(27.5 6 1.5 nm). The antiferromagnetic highfield susceptibility(v anti) and the saturation magnetization(M s) for the weak ferromagnetic component in hematite are both correlated negatively with temperature between 20 and 300 K, and grain size in the vicinity of the SP threshold. For very small grains(below 16–17 nm), T b increases with increasing particle size.However, beyond this size, it descends with increasing particle size up to 19 nm before increasing with grain size again. These trends are attributed to the competition of surface anisotropy and bulk anisotropy(elastic anisotropy). This new study substantially improves our understanding of the complex magnetic properties of fine-grained Al-Hm and pure-Hm in natural sample, which is significant for the paleoenvironmental and climatic studies of natural samples, e.g., red beds/soils.

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New constraints on climate forcing and variability in the circum-Mediterranean region from magnetic and geochemical observations of sapropels S1,S5 and S6

New constraints on climate forcing and variability in the ci...

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中国科学院地质与地球物理研究所2012年度（第12届）...

作者： Qingsong Liu Juan C.Larrasoana jose TOrrENT Andrew P.Roberts Eelco J.Rohling Zhifeng Liu Zhaoxia Jiang Paleomagnetism and Geochronology Laboratory(SKL-LE) Institute of Geology and GeophysicsChinese Academy of Sciences Research School of Earth Sciences The Australian National UniversityCanberraACT 0200Australia

Eastern Mediterranean sapropels are organic-rich layers whose formation was triggered during boreal summer insolation maxima(precession minima).Sapropel formation is associated with increased precipitation and runoff from Europe and North Africa,although Lhe relative influence of high- and low-latitude climate mechanisms is not fully resolved.Likewise,it remains uncertain how centennial-scale interruptions in conditions that give rise to sapropels may reflect atmospheric circulation changes in low latitudes.We present magnetic,geochemical, and diffuse reflectance spectroscopy data from three sapropels that are representative of glacial(S6) and interglacial(S1 S5]conditions in the eastern Mediterranean Sea Lo assess environmental changes associated with sapropel formation.The extent of diagenetic magnetite dissolution and authigenic formation of finegrained greigite in these sapropels and their underlying dissolution intervals are linked to enhanced sulphidic conditions during sapropel formation.Aeolian hematite and goethite are largely unaffected by this reductive dissolution except within the interglacial sapropel S5 and its underlying dissolution interval,which formed under relatively stronger sulphidic conditions.Nevertheless,low hematite contents indicate that the three studied sapropels accumulated under reduced aeolian dust inputs in response to an intensified African monsoon, which resulted in expansion of savannah landscapes into NE Saharan dust source areas.Small variations in goethite contents across sapropels indicate additional aeolian entrainment of goethite that formed under previous wet phases in the NE Sahara or in subtropical savannahs located further south.We link short-lived dust abundance peaks within sapropels S1 and S6 to centennial-scale periods of enhanced bottom-water circulation reported previously for these sapropels.Although these sapropel interruptions are driven by high-latitude cooling events,our results indicate that such centennial-scale episodes of atmospheric reorganization affe

关键词： Sapropels Circum-Mediterranean region Environmental change Savannah landscapes

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The Transcervical Extended Access, a Feasible Approach for the Surgical Treatment of Benign Tumors of the Posterior Mediastinum?

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Surgical Science 2018年第3期9卷 128-133页

作者： David Perez Francisco Hernandez jose Ramon Cano Wolker Tavarez Gara torrent Santiago Quevedo Luis Lopez Department of Thoracic Surgery Insular Materno-Infantil University Hospital Las Palmas de Gran Canaria Spain

Transcervical approach for tumors of the posterior mediastinum is traditionally thought not to be indicated. Hereby we report on a case of a patient with a huge neurogenic tumor of the posterior mediastinum which was successfully excised through a transcervical extended approach and, additionally, the variety of surgical approaches used to remove tumors of the posterior mediastinum is discussed. The new refined techniques of transcervical extended mediastinal operations, which are recently gaining popularity among surgeons, allowed for a safe dissection of the tumor, thus patient could benefit from a short painless postoperative course. The authors suggest that surgeons trained in these particular techniques should consider the choice of the transcervical extended access in selected cases of benign tumors of the posterior mediastinum.

关键词： Mediastinum Neurogenic Neoplasms Thoracic Surgery Transcervical Access

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Brain and spinal cord trauma:what we know about the therapeutic potential of insulin growth factor 1 gene therapy

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Neural Regeneration Research 2023年第2期18卷 253-257页

作者： María jose Bellini Florencia Labombarda Lab de Bioquímica del Envejecimiento INIBIOLP-CONICETFacultad de Ciencias MedicinaUniversidad Nacional de La PlataLa PlataArgentina Laboratory of Neuroendocrine Biochemistry IBYME-CONICETBuenos AiresArgentina Department of Human Biochemistry Faculty of MedicineUniversidad de Buenos AiresBuenos AiresArgentina

Although little attention has been paid to cognitive and emotional dysfunctions observed in patients after spinal co rd injury,several reports have described impairments in cognitive abilities.Our group also has contributed significantly to the study of cognitive impairments in a rat model of spinal co rd injury.These findings are very significant because they demonstrate that cognitive and mood deficits are not induced by lifestyle changes,drugs of abuse,and combined medication.They are related to changes in brain structures involved in cognition and emotion,such as the hippocampus.Chronic spinal cord injury decreases neurogenesis,enhances glial reactivity leading to hippocampal neuroinflammation,and trigge rs cognitive deficits.These brain distal abnormalities are recently called te rtiary damage.Given that there is no treatment for Tertiary Damage,insulin growth factor 1 gene therapy emerges as a good candidate.Insulin growth factor 1 gene thera py recove rs neurogenesis and induces the polarization from pro-inflammato ry towards anti-inflammatory microglial phenotypes,which represents a potential strategy to treat the neuroinflammation that supports te rtiary damage.Insulin growth factor 1 gene therapy can be extended to other central nervous system pathologies such as traumatic brain injury where the neuroinflammatory component is crucial.Insulin growth factor 1 gene therapy could emerge as a new therapeutic strategy for treating traumatic brain injury and spinal cord injury.

关键词： cognitive impairments gene therapy hippocampus insulin growth factor 1 microglial cells neurodegeneration neurogenesis neuroinflammation spinal cord injury traumatic brain injury

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Microwave photonics

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Science China(Information Sciences) 2022年第12期65卷 49-112页

作者： Jianping YAO jose CAPMANY Microwave Photonics Research Laboratory School of Electrical Engineering and Computer Science University of Ottawa ITEAM Research Institute Universitat Politècnica de València iPronics Programmable Photonics

Microwave photonics, an interdisciplinary field that combines microwave engineering and photonic technology for the generation, transmission, processing, and control of microwave signals, to take advantage of the broad bandwidth, high frequency, and low loss offered by modern photonics, has been intensively researched for the last few decades, and numerous solutions have been proposed and demonstrated. In this article, an overview about microwave photonics is provided which covers the basic concepts of microwave photonics, photonic-assisted microwave signal generation, photonic-assisted microwave signal processing, and true time delay beamforming. The implementation of microwave photonic systems based on photonic integrated circuits is also reviewed, including the design, fabrication, and material platforms, application-specific photonic integrated circuits for microwave photonics, and programmable integrated microwave photonics.The challenges and future applications of microwave photonics are also discussed.

关键词： microwave photonics photonic integrated circuits microwave photonic link microwave photonic signal processor optoelectronic oscillator radio over fiber

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