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打破干旱区土地退化与贫困的联结

Science Bulletin 2022年第24期67卷 2508-2512页

作者：吕楠傅伯杰 Mark Stafford-Smith fernando t.Maestre 程临海 State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China CSIRO Land&Water Canberra ACT 2601Australia Department of Ecology University of AlicanteCarretera de San Vicente del RaspeigAlicante 03690Spain Multidisciplinary Institute for Environment Studies“Ramon Margalef” University of AlicanteCarretera de San Vicente del RaspeigAlicante 03690Spain

Drylands cover approximately 41%of the global land surface and provide homes to more than two billion people. Collectively,drylands constitute the largest terrestrial biome on the planet,and despite their low productivity per land area compared to other ecosystems, they have a major impact on the ecological functioning and climate of our planet through carbon storage, albedo, dust production, and water cycling [1].

关键词： planet 土地退化 cycling

Slope reliability and back analysis of failure with geotechnical parameters estimated using Bayesian inference

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第3期11卷 628-643页

作者： Luis-fernando Contreras Edwin t.Brown the University of Queensland St Lucia Campus

A Bayesian approach is proposed for the inference of the geotechnical parameters used in slope design.the methodology involves the construction of posterior probability distributions that combine prior information on the parameter values with typical data from laboratory tests and site investigations used in design.the posterior distributions are often complex,multidimensional functions whose analysis requires the use of Markov chain Monte Carlo(MCMC)methods.these procedures are used to draw representative samples of the parameters investigated,providing information on their best estimate values,variability and correlations.the paper describes the methodology to define the posterior distributions of the input parameters for slope design and the use of these results for evaluation of the reliability of a slope with the first order reliability method(FORM).the reliability analysis corresponds to a forward stability analysis of the slope where the factor of safety(FS)is calculated with a surrogate model from the more likely values of the input parameters.the Bayesian model is also used to update the estimation of the input parameters based on the back analysis of slope failure.In this case,the condition FS?1 is treated as a data point that is compared with the model prediction of FS.the analysis requires a sufficient number of observations of failure to outbalance the effect of the initial input parameters.the parameters are updated according to their uncertainty,which is determined by the amount of data supporting them.the methodology is illustrated with an example of a rock slope characterised with a Hoek-Brown rock mass strength.the example is used to highlight the advantages of using Bayesian methods for the slope reliability analysis and to show the effects of data support on the results of the updating process from back analysis of failure.

关键词： Bayesian analysis Hoek-Brown criterion Slope reliability Back analysis of failure

Bayesian data analysis to quantify the uncertainty of intact rock strength

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第1期10卷 11-31页

作者： Luis fernando Contreras Edwin t.Brown Marc Ruest the University of Queensland St Lucia CampusBrisbaneQLD 4072Australia Golder Associates Pty.Ltd. BrisbaneAustralia

One of the main difficulties in the geotechnical design process lies in dealing with uncertainty. Uncertainty is associated with natural variation of properties, and the imprecision and unpredictability caused by insufficient information on parameters or models. Probabilistic methods are normally used to quantify uncertainty. However, the frequentist approach commonly used for this purpose has some drawbacks.First, it lacks a formal framework for incorporating knowledge not represented by data. Second, it has limitations in providing a proper measure of the confidence of parameters inferred from data. the Bayesian approach offers a better framework for treating uncertainty in geotechnical design. the advantages of the Bayesian approach for uncertainty quantification are highlighted in this paper with the Bayesian regression analysis of laboratory test data to infer the intact rock strength parameters σand mused in the Hoek-Brown strength criterion. two case examples are used to illustrate different aspects of the Bayesian methodology and to contrast the approach with a frequentist approach represented by the nonlinear least squares(NLLS) method. the paper discusses the use of a Student’s t-distribution versus a normal distribution to handle outliers, the consideration of absolute versus relative residuals, and the comparison of quality of fitting results based on standard errors and Bayes factors. Uncertainty quantification with confidence and prediction intervals of the frequentist approach is compared with that based on scatter plots and bands of fitted envelopes of the Bayesian approach. Finally, the Bayesian method is extended to consider two improvements of the fitting analysis. the first is the case in which the Hoek-Brown parameter, a, is treated as a variable to improve the fitting in the triaxial region. the second is the incorporation of the uncertainty in the estimation of the direct tensile strength from Brazilian test results within the overall evaluation of the intact rock strength.

关键词： Uncertainty Intact rock strength Bayesian analysis Hoek-Brown criterion

Why Pheidippides could not believe in the‘Central Governor Model’:Popper's philosophy applied to choose between two exercise physiology theories

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Sports Medicine and Health Science 2022年第1期4卷 1-7页

作者： fernando A.M.S.Pompeu the Physical Education Graduate Program Rio de Janeiro Federal UniversityRio de JaneiroUFRJBrazil

An important epistemological problem has been faced by Exercise Physiologists.On one hand,one theory explains the fatigue through a ceiling effect of oxygen uptake.On the other hand,the new theory proposes that an encephalon mechanism would stop the effort before a catastrophic homeostasis failure.Many physiologists have looked for evidence to support their favourite theory even though the induction logic problem does not allow to prove whether truth is discovered;however,it is possible to prove that it does not occur.When some researchers fail to test their hypotheses,they use relativism to bring up their theories again.Noakes and his colleagues have based their theory on relativism,because it is impossible to refute by empirical observation.It also doesn't explain all phenomena that the oldest Hill's theory is able to explain.Noakes's theory isn't more accurate in its previsions.Noakes did not check whether the oxygen uptake plateau occurs in suitable tests to measure on the mouth what happens in the muscles.Finally,it doesn't propose new tests for the encephalon role during maximal effort,as that is expected in scientific work.For all of these reasons,it is possible to conclude there are no advantages in switching to the“Central Governor”theory.

关键词： Epistemological problem VO_(2)plateau Positivism Scientific revolutions and philosophy of science

Functional leaf and size traits determine the photosynthetic response of 10 dryland species to warming

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Journal of Plant Ecology 2016年第6期9卷 773-783页

作者： Enrique Valencia JoséL.Quero fernando t.Maestre Departamento de Biología y Geología Física y Química InorgánicaEscuela Superior de Ciencias Experimentales y TecnologíaUniversidad Rey Juan CarlosC/Tulipán s/n28933 MóstolesSpain Departamento de Ingeniería Forestal Escuela Técnica Superior de Ingeniería Agronómica y de MontesUniversidad de Córdoba Campus de Rabanales CrtaN-IV km.396C.P.14071 CórdobaSpain

Aims Relatively few studies so far have assessed how ongoing global warming will affect the photosynthetic performance of dryland plant species.We evaluated the effects of warming on the photosynthetic rates of 10 species with contrasting functional attributes,and whether their functional traits modulated photosynthetic responses to warming.Methods A common garden experiment was conducted over 2 years with distinct environmental conditions(drier vs.wetter year).the experiment was designed as a randomized block design with two treatments:warming(control vs.~2.9℃ temperature increase)and species(Agropyron cristatum,Festuca ovina,Lygeum spartum,Medicago sativa,Plantago lanceolata,Psoralea bituminosa,Sanguisorba minor,Hedysarum coronarium,Dorycnium pentaphyllum and Phlomis herba-venti).We linked functional traits measurements with temporal variations in photosynthetic responses to warming.Important Findings In the drier year,warming increased photosynthetic rates at the beginning of the growing season,suggesting a modification in the growing period(earlier spring).In the wetter year,functional traits modulated photosynthetic responses to warming.Larger species with shorter leaves(e.g.M.sativa)had higher photosynthetic rates under warming compared to smaller species with larger leaves(e.g.F.ovina).Our results highlight the importance of(i)studying photosynthetic responses along different years and(ii)considering functional traits when evaluating photosynthetic responses to climate change,particularly in stressful environments such as drylands.

关键词： photosynthesis climate change Mediterranean functional traits open top chambers

Exploring multifaceted factors in chronic kidney disease risk: A comprehensive analysis of biochemistry, lifestyle, and inflammation in elderly Chinese individuals

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World Journal of Clinical Cases 2024年第5期12卷 1033-1035页

作者： fernando Cardona Unitat de Genètica Molecular Instituto de Biomedicina de Valencia–CSICValencia 46010Spain Centro de investigación Biomédica en Red Enfermedades Neurodegenerativas(CIBERNED) Instituto de Salud Carlos IIIMadrid 28029Spain Departamento de Biotecnología Escuela Técnica Superior de Ingeniería Agronómica y del Medio Natural(ETSIAMN)Univeristat Politècnica de ValenciaValencia 46022Spain

this letter praises a recent article in the World Journal of Clinical Cases(Roles of biochemistry data,lifestyle,and inflammation in identifying abnormal renal function in old Chinese),examining factors affecting abnormal renal function in elderly Chinese using advanced machine learning.It highlights the importance of uric acid,age,hemoglobin,body mass index,sport hours,and systolic blood pressure.the study's holistic approach,integrating lifestyle and inflammation,offers a nuanced understanding of chronic kidney disease risk factors.the letter suggests exploring mechanistic pathways of hyperuricemia,the link between anemia and renal function,and the connection between body mass index and estimated glomerular filtration rate.It advocates investigating physical activity's impact on renal health and the independent effects of blood pressure.the study significantly contributes to chronic kidney disease understanding,proposing avenues for further exploration and interventions.Commendations are extended to the authors and the journal.

关键词： Biochemistry data Lifestyle Machine learning Renal function

A Simpler Memristor Emulator Based on Varactor Diode

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Chinese Physics Letters 2018年第5期35卷 144-147页

作者：于东升孙婷婷郑辞晏 H.H.C.Iu t.fernando School of Electrical and Power Engineering China University of Mining and Technology School of Electrical Electronic and Computer Engineering The University of Western Australia

A new memristor（MR） emulator is designed by making use of only three current-feedback operational amplifiers,one varactor diode, one capacitor and five resistors. As compared with other reported MR emulators, only three active devices and ten components in total are required for realizing this MR emulator, and hence this emulator can be regarded as a simpler one for the moment. the results obtained by Multisim simulation and experimental prototypes are given to verify the practicality and feasibility of this MR emulator.

关键词： MR As

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干旱区主导全球植被生产力增加趋势

Science Bulletin 2023年第2期68卷 224-232,M0004页

作者：王帅傅伯杰魏芳莉朴世龙 fernando t.Maestre Lixin Wang Wenzhe Jiao 刘焱序李琰李长嘉赵文武 State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Sino-French Institute for Earth System Science College of Urban and Environmental SciencesPeking UniversityBeijing 100871China Department of Ecology University of AlicanteCarretera de San Vicente del RaspeigAlicante 03690Spain Multidisciplinary Institute for Environment Studies“Ramon Margalef” University of AlicanteCarretera de San Vicente del RaspeigAlicante 03690Spain Department of Earth Sciences Indiana University-Purdue University IndianapolisIndianapolis IN 46202USA

旱区(drylands)是指年平均降雨量与潜在蒸散发之比小于0.65的区域,占全球陆地表面的42%,是最易受气候变化影响的地区之一.然而,目前关于旱区植被对气候变化的响应特征及其对全球变绿和陆地生态系统生产力变化的相对贡献仍不清楚.本研究... 详细信息

旱区(drylands)是指年平均降雨量与潜在蒸散发之比小于0.65的区域,占全球陆地表面的42%,是最易受气候变化影响的地区之一.然而,目前关于旱区植被对气候变化的响应特征及其对全球变绿和陆地生态系统生产力变化的相对贡献仍不清楚.本研究通过集成模型和遥感数据分析发现,旱区对全球变绿的贡献较小,仅占33%±15%,但却主导了全球植被生产力(GPP)增加趋势,贡献达65%±16%旱区植被光合利用效率升高是解释变绿与生产力增加不一致的主要原因.旱区光能利用率主要受土壤水分的影响,大气水汽压差作用不显著,而非旱区主要受大气水汽压差的影响,土壤水的作用有限.因此,需要强调使用不同的水分胁迫指标来预测不同区域植被生产力变化的重要性,这也有助于理解较长时间尺度上植被绿度与生产力之间的解耦关系.

关键词：光能利用率水汽压差气候变化影响植被生产力旱区潜在蒸散发相对贡献集成模型

Pannexin 1-based channels activity as a novel regulator of multiple sclerosis progression

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Neural Regeneration Research 2020年第1期15卷 65-66页

作者： fernando C.Ortiz Carlos Puebla Mechanisms on Myelin Formation and Repair Laboratory Instituto de Ciencias BiomedicasFacultad de Ciencias de la SaludUniversidad Autonoma de ChileSantiagoChile Cellular Physiology Laboratory Instituto de Ciencias BiomedicasFacultad de Ciencias de la SaludUniversidad Autonoma de ChileSantiagoChile

Multiple sclerosis(MS):MS is a neurodegenerative disease affecting around 2.5 million people worldwide,representing the second cause of disabilities in the young adult population.MS is a demyelinating pathology which originates in the autoimmune attack of t and B lymphocytes against myelin.this lack of myelin leads,in turn,to axonal degeneration,neuronal death and the consequent neurological disabilities(Franklin and Ffrench-Constant,2017).A main hallmark of MS is a preserved local neuroinflammatory environment.It is now acknowledged that this persistent inflammatory scenario is a central and common condition in almost all neurodegenerative pathologies(as in Parkinson’s and Alzheimer’s diseases,among others)controlling and modulating the regulatory responses of the system to the triggering insult.In the case of MS,this original insult corresponds to the loss of myelin(Chitnis and Weiner,2017;Franklin and Ffrench-Constant,2017).

关键词： Franklin representing degeneration