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Risk factors connected to gastrointestinal parasites in mantled Alouatta palliata mexicana and black howler monkeys Alouatta pigra living in continuous and in fragmented rainforests in Mexico

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Current Zoology 2012年第3期58卷 375-383页

作者： Genoveva trejo-MACIAS Alejandro ESTRADA Estacien de Biologfa Tropical Los Tuxtlas Instituto de BiologiaUNAMCircuito Exterior junto a Jardfn BotainicoM6xicoDEMexico

In this study we document the prevalence of gastrointestinal parasites （helminths and protozoans） found in fecal samples of populations of Alouatta palliata mexicana and ofA. pigra in Los Tuxtlas and in Palenque, southeast Mexico, and its re- lation to habitat condition, sex/age and season. Nineteen parasite morphotypes were detected in the fecal samples from populations of the two howler monkeys, of which 58% were shared by both species. When considering all parasite species, populations of the two howler species were more likely to be parasitized in fragmented habitat compared to continuous habitat. Individuals of both howler monkey species that lived in fragmented habitat had a higher prevalence of Controrchis biliophilus. A. p. mexicana individuals had a higher prevalence of Trypanoxyuris minutus than A. pigra, probably the result of the larger group sizes found in the former species, and T. minutus was more likely to be found in A. palliata individuals that lived in fragmented habitat. Adult A. p. mexicana males had a higher risk of being parasitized compared to adult females, but these differences were not detected in A. pigra, Parasite species such as Entamoeba sp., Nematoda sp. 28, Nematoda sp. B and Parabronema sp. where only found during the wet season in both howler monkey species. Populations of both howler monkey species had a higher prevalence of Nematoda sp. A in the wet season and Ascaridae eggs were only detected during the wet season in A. pigra. Other parasites detected displayed no clear seasonal pattern [Current Zoology 58 （3）： 375-383, 2012].

关键词： Gastrointestinal parasites Habitat fragmentation Seasonality Alouatta palliata mexicana Alouatta pigra Mexico

Complex Systems in Economics and Where to Find Them

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Journal of Systems Science & Complexity 2021年第1期34卷 314-338页

作者： GOMES orlando GUBAREVA Mariya ISCAL-Lisbon Accounting and Business School Instituto Politécnico de Lisboaand CEFAGE-ISCAL/IPL Research CenterISCALAv.Miguel Bornbarda 201069-035 LisbonPortugal Accounting and Business School Instituto Politécnico de Lisboa SOCIUS-Research Centre in Economic and Organizational Sociology CSG-Research in Social Sciences and Management

The economy as a whole and most of its constituent parts, like markets, government institutions, firms, or households, are inherently complex conceptual constructions. Micro-level diversity,decentralized interaction, self-organization, adaptation and learning, emergence, and evolution, are some of the fundamental features that the above entities share and that allow to classify them as being complex entities. In a complex economic system, existing structures of interaction are in constant mutation as individual agents contact and influence one another and, by doing so, reshape the macro environment in which socio-economic relations unfold. Notwithstanding the observed pervasiveness of complexity in economics, there are a few areas of economic thought where the discussion on the theme has gained an exceptional relevance. In this article, six of such areas are identified and their complex nature is highlighted and scrutinized. These pertain to:(i) Knowledge interactions and technological innovation;(ii) Corporate design and organizational learning;(iii) Public policies directed at market regulation;(iv) Banking and financial markets;(v) Environmental economics, sustainability,and climate change;and(vi) income inequality.

关键词： Agent-based models complex networks complex systems emergent phenomena evolutionary nature market regulation public policies

Robust Control of a Bevel-Tip Needle for Medical Interventional Procedures

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IEEE/CAA Journal of Automatica Sinica 2020年第1期7卷 244-256页

作者： Surender Hans Felix orlando Maria Joseph Department of Electrical Engineering Indian Institute of Technology RoorkeeRoorkeeUttarakhand 247667India

In minimally invasive surgery, one of the main objectives is to ensure safety and target reaching accuracy during needle steering inside the target organ. In this research work, the needle steering approach is determined using a robust control algorithm namely the integral sliding mode control(ISMC) strategy to eliminate the chattering problem associated with the general clinical scenario. In general, the discontinuity component of feedback control input is not appropriate for the needle steering methodology due to the practical limitations of the driving actuators. Thus in ISMC, we have incorporated the replacement of the discontinuous component using a super twisting control(STC)input due to its unique features of chattering elimination and disturbance observation characteristics. In our study, the kinematic model of an asymmetric flexible bevel-tip needle in a soft-tissue phantom is used to evaluate stability analysis. A comparative study based on the analysis of chattering elimination is executed to determine the performance of the proposed control strategy in real-time needle steering with conventional sliding mode control using vision feedback through simulation and experimental results. This validates the efficacy of the proposed control strategy for clinical needle steering.

关键词： Minimal invasive surgery needle steering nonholonomic system robust control sliding mode control

Analysis of three-dimensional vortexes below the free surface in a continuous casting mold

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International Journal of Minerals,Metallurgy and Materials 2011年第4期18卷 397-406页

作者： Cesar A.Real-Ramirez Jesus I.Gonzalez-trejo Universidad Autonoma Metropolitana-Azcapotzalco.San Pablo 180 02200Mexico CityMexico

To study fluctuations of the free surface of liquid steel in the mold,two different models with the same casting conditions but different thicknesses were employed to analyze the hydrodynamic behavior at the top of the *** first model was a standard thickness slab,and the second had a thickness three times *** is found with the second model that above the plane formed by the steel jets,it is possible to observe four three-dimensional vortexes that interact with the submerged entry nozzle（SEN）and mold *** using a biphasic model to simulate the interface between the liquid and air inside the mold,the flow asymmetry and the fluctuations of the free surface can be clearly observed.

关键词： continuous casting molds flow patterns three dimensional vortes mathematical models computer simulation

Products of Distributions,Conservation Laws and the Propagation of δ'-Shock Waves

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Chinese Annals of Mathematics,Series B 2012年第3期33卷 367-384页

作者： Carlos orlando R. SARRICO CMAF University of LisbonAv.Prof.Gama Pinto 21649-003Portugal

This paper contains a study of propagation of singular travelling waves u（x, t） for conservation laws ut ＋ [Ф（u）]x = ψ（u）, where Ф, ψ are entire functions taking real values on the real axis. Conditions for the propagation of wave profiles β ＋ mδ and β ＋ mδt are presented （β is a real continuous function, m ≠ 0 is a real number and δ＇ is the derivative of the Dirac measure 5）. These results are obtained with a consistent concept of solution based on our theory of distributional products. Burgers equation ut ＋（u2/2）x = 0, the iffusionless Burgers-Fischer equation ut ＋ a（u2/2）x = ru（1 - u/k） with a, r, k being positive numbers, Leveque and Yee equation ut ＋ ux = μx（1 - u）（u - u/k） with μ ≠ 0, and some other examples are studied within such a setting. A ＂tool box＂ survey of the distributional products is also included for the sake of completeness.

关键词： Conservations laws Travelling waves δ^-shock waves δ-shock waves δ-solitons Propagation of distributional wave profiles

Optimization of the treatment with immunosuppressants and biologics in inflammatory bowel disease

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World Journal of Gastroenterology 2014年第29期20卷 9675-9690页

作者： Sara Renna Ambrogio orlando Division of Internal Medicine ‘‘Villa Sofia-V.Cervello’’ Hospital

Many placebo controlled trials and meta-analyses evaluated the efficacy of different drugs for the treatment of inflammatory bowel disease (IBD), including immunosuppressants and biologics. Their use is indicated in moderate to severe disease in non responders to corticosteroids and in steroid-dependent patients, as induction and maintainance treatment. Infliximab, as well as cyclosporine, is considered a second line therapy in the case of severe ulcerative colitis, or non-responders to intravenous corticosteroids. An adequate dosage and duration of therapy with thiopurines should be reached before evaluating their efficacy. Methotrexate is a valid option in patients with Crohn’s disease but its use is confined to patients who are intolerant or non-responders to thiopurines. Evidence for the use of methotrexate in ulcerative colitis is insufficient. The use of thalidomide and mycophenolate mofetil is not recommended in patients with inflammatory bowel disease, these treatments could be considered in case of failure of all other therapeutic options. In patients with moderately active ulcerative colitis, refractory to thiopurines, the use of tacrolimus is considered an alternative to biologics. An increase of the dose or a decrease in the interval of administration of biological treatment could be useful in the presence of an incomplete clinical response. In the case of primary failure of an anti-tumor necrosis factor alpha a switch to another one should be considered. Data on the efficacy of combination therapy are up to now insufficient to consider this strategy in all IBD patients. The final outcome of the treatment should be considered the clinical remission, with mucosa healing, and not the clinical response. The evaluation of serum concentration of thiopurine methyl transferase activity, thiopurine metabolites, biologic serum levels and antibiologic antibodies could be useful for the management of the treatment but it has not been routinely applied in cl

关键词： Inflammatory bowel disease Optimization Immosuppressants Biologics Crohn's disease Ulcerative colitis

Assessment of forest dieback on the Moroccan Central Plateau using spectral vegetation indices

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Journal of Forestry Research 2023年第3期34卷 793-808页

作者： Youssef Dallahi Amal Boujraf Modeste Meliho Collins Ashianga orlando Laboratory of Microbial Biotechnologies Agrosciences and Environment(BioMAgE)Faculty of Sciences SemlaliaCadi Ayyad UniversityMarrakechMorocco Laboratoire des Productions Végétale Animales et Agro-industrieEquipe de BotaniqueBiotechnologie et Protection des PlantesFacultédes SciencesUniversitéIbn TofailKenitraMorocco Sociétés TerritoiresHistoires et PatrimoinesFacultédes Lettres et des Sciences HumainesUniversitéMohammed VRabatMorocco Rabat Morocco

Cork oak forests in Morocco are rich in resources and services thanks to their great biological diversity,playing an important ecological and socioeconomic *** degradation of the forests has been accentuated in recent years by signifi cant human pressure and eff ects of climate change;hence,the health of the stands needs to be *** this study,the Google Engine Earth platform was leveraged to extract the normalized diff erence vegetation index(NDVI)and soil-adjusted vegetation index,from Landsat 8 OLI/TIRS satellite images between 2015 and 2017 to assess the health of the Sibara Forest in *** results highlight the importance of interannual variations in NDVI in forest monitoring;the variations had a signifi cantly high relationship(p<0.001)with dieback *** was positively and negatively correlated with mean annual precipitation and mean annual temperature with respective coeffi cients of 0.49 and−0.67,highlighting its ability to predict phenotypic changes in forest *** interannual variation in NDVI between 2016 and 2017 seemed to confi rm fi eld observations of cork oak dieback in 2018,with the largest decreases in NDVI(up to−38%)in December in the most-aff ected *** of the infl uence of ecological factors on dieback highlighted the role of substrate as a driver of dieback,with the most severely aff ected plots characterized by granite-granodiorite substrates.

关键词： Forest health monitoring Remote sensing Dieback Vegetation indices Sibara forest

Correlative microscopy of Purkinje cells

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BIOCELL 2012年第1期36卷 1-29页

作者： orlando J.CASTEJÓN Instituto de Investigaciones Biologicas“Drs.orlando Castejón and Haydee Viloria de Castejón”.Facultad de Medicina.Universidad del Zulia.Maracaibo.Venezuela

The Purkinje cell and their synaptic contacts have been described using(1)light microsocopy,(2)transmission and scanning electron microscopy,and freeze etching technique,(3)conventional and field emission scanning electron microscopy and cryofracture methods,(4)confocal laser scanning microscopy using intravital stain FM64,and(5)immunocytochemical techniques for Synapsin-I,PSD9-5,GluR1 subunit of AMPA receptors,N-cadherin,and CamKII *** outer surface and inner content of plasma membrane,cell organelles,cytoskeleton,nucleus,dendritic and axonal processes have been exposed and analyzed in a three-dimensional *** intramembrane morphology,in bi-and three-dimensional views,and immunocytochemical labeling of synaptic contacts with parallel and climbing fibers,basket and stellate cell axons have been *** etching technique,field emission scanning microscopy and cryofracture methods,and GluR1 immunohistochemistry showed the morphology and localization of postsynaptic *** cell shows N-cadherin and CamKII alpha *** correlative microscopy approach provides a deeper understanding of structure and function of the Purkinje cell,a new three-dimensional outer and inner vision,a more detailed study of afferent and intrinsic synaptic junctions,and of intracortical circuits.

关键词： cerebellar cells synaptic contacts electron microscopy immunohistochemistry

Mouse cerebellar Purkinje cell damage induced by diphenylhydantoin acute intoxication

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BIOCELL 2015年第2期39卷 33-39页

作者： orlando J.CASTEJÓN Biological Research Institute and Faculty of Medicine Zulia UniversityMaracaiboVenezuela

Twenty one days old Swiss albino mice that received diphenylhydantoin(25 mg/kg,i.p.,daily for 15 days)progressively developed gait alterations,changes of behavior and cerebellar *** slices were processed by conventional transmission electron *** body of Purkinje cells exhibited fragmented limiting plasma membranes,dilated nuclear envelopes,swelling and disassembly of nuclear pores,enlargement of rough and smooth endoplasmic reticulum and a notable detachment of membrane associated ribosomes,to-gether with distorted vacuoles of smooth endoplasmic reticulum,bizarre shaped and swollen mitochondria with dilated cristae,as well as disrupted limiting lysosomal *** axosomatic synapses apparently corresponding to basket cell axonal endings were *** Purkinje cell axon initial segments exhibited vacuolar degeneration of myelin sheath,dilated axoplasmic tubular bundles,fragmented axonal mem-branes,swollen mitochondria,and disassembly of cytoskeletal *** edematous and clear secondary and tertiary dendrites exhibited areas of dilated cisterns of smooth endoplasmic reticulum,clear and dark mul-tivesicular bodies,and coated *** dendritic ramifications exhibited an electron dense *** and large climbing fiber endings were observed making axodendritic synapses with edematous Purkinje *** presynaptic endings appeared depleted or containing few synaptic *** syn-apses did not exhibit pre-and postsynaptic *** the molecular layer,the edematous synaptic varicosities of parallel fibers containing pleomorphic synaptic vesicles and dense extravesicular substance were observed making asymmetric synaptic contacts with swollen Purkinje dendritic *** findings are postulated as pathogenic mechanisms of mouse cerebellar ataxia.

关键词： Purkinje cell cytotoxic edema diphenylhydantoin toxicity electron microscopy