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Friction 2024年第10期12卷 2325-2343页

作者： cristina GARCÍA-CABEZÓN Juan Alfonso NARANJO Celia GARCÍA-HERNÁNDEZ cristina BERGES Gemma HERRANZ Fernando MARTÍN-PEDROSA Materials Engineering E.I.I.Universidad de ValladolidValladolid 47011Spain INEI-Escuela Técnica Superior de Ingeniería Industrial(ETSII) Universidad de Castilla La ManchaCastilla-La Mancha 13071Spain

Fused filament fabrication(FFF)is one of the additive manufacturing processes which has gained more interest because of its simplicity and *** technology is similar to the conventional metal injection moulding(MIM)process,consisting of the feedstock preparation of metal powder and polymer binders,followed by layer-by-layer 3D printing(FFF)or injection(MIM)to create green parts and,finally,debinding and ***,both technologies provide near-dense *** work presents an in-depth study of the processing method’s *** porosity,microstructure,hardness,corrosion,and tribocorrosion behaviour are compared for 17-4 PH SS samples processed from powder by additive manufacturing using FFF and MIM,as well as conventional powder metallurgy(PM)*** samples exhibited the highest macro and microhardness,while corrosion behaviour was similar for both MIM and FFF samples,but superior in comparison to conventional PM ***,the FFF-as fabricated samples displayed a significant improvement in tribocorrosion resistance that could be explained by the higher proportion of delta ferrite and retained austenite in their microstructure.

关键词： 17-4 PH SS fused filament fabrication(FFF) metal injection moulding(MIM) corrosion behaviour powder metallurgy(PM) tribocorrosion behaviour

Formation of iodo-trihalomethanes, iodo-haloacetic acids, and haloacetaldehydes during chlorination and chloramination of iodine containing waters in laboratory controlled reactions

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Journal of Environmental Sciences 2017年第8期29卷 127-134页

作者： cristina Postigo Susan D.Richardson Damia Barceló Water and Soil Quality Research Group Department of Environmental Chemistry Institute of Environmental Assessment and Water Research (IDAEA-CSIC) Barcelona Spain Department of Chemistry and Biochemistry University of South Carolina SC 29208 United States Catalan Institute for Water Research(ICRA) Parc Científic i Tecnològic de la Universitat de Girona17003 GironaSpain

Iodine containing disinfection by-products（I-DBPs） and haloacetaldehydes（HALs） are emerging disinfection by-product（DBP） classes of concern. The former due to its increased potential toxicity and the latter because it was found to be the third most relevant DBP class in mass in a U.S. nationwide drinking water study. These DBP classes have been scarcely investigated, and this work was performed to further explore their formation in drinking water under chlorination and chloramination scenarios. In order to do this, iodo-trihalomethanes（I-THMs）,iodo-haloacetic acids（I-HAAs） and selected HALs（mono-HALs and di-HALs species, including iodoacetaldehyde） were investigated in DBP mixtures generated after chlorination and chloramination of different water matrices containing different levels of bromide and iodide in laboratory controlled reactions. Results confirmed the enhancement of I-DBP formation in the presence of monochloramine. While I-THMs and I-HAAs contributed almost equally to total I-DBP concentrations in chlorinated water, I-THMs contributed the most to total I-DBP levels in the case of chloraminated water. The most abundant and common I-THM species generated were bromochloroiodomethane, dichloroiodomethane, and chlorodiiodomethane. Iodoacetic acid and chloroiodoacetic acid contributed the most to the total I-HAA concentrations measured in the investigated disinfected water. As for the studied HALs, dihalogenated species were the compounds that predominantly formed under both investigated treatments.

关键词： Iodinated disinfection by-products Chlorination Chloramination Drinking water Mass spectrometry Iodo-trihalomethanes Iodo-haloacetic acids Haloacetaldehydes

A CFD–DEM study of the behaviour of single-solid and binary mixtures in a pyramidal spouted bed

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Particuology 2019年第1期17卷 79-91页

作者： Filippo Marchelli cristina Moliner Barbara Bosio Elisabetta Arato Faculty of Science and Technology Free University of Bozen-BolzanoPiazza Universita 539100 BolzanoItaly Department of Civil Chemical and Environmental EngineeringUniversity of GenovaVia all'Opera Pia 1516145 GenovaItaly

We simulated a lab-scale cold-flow spouted bed through computational fluid dynamics (CFD), coupled with the discrete element method (DEM) for the solid phase, using a commercial CFD program, ANSYS FLUENT 18.0. To limit the computational expense, we tested both a simplified pseudo-2D geometry and a complete 3D geometry. We found that the Haider and Levenspiel drag model is suitable for the pseudo-2D geometry;however, this model does not correctly predict fluidisation in the 3D geometry. Conversely, the Gidaspow drag model behaves accurately in the 3D geometry but overestimates the motion of particles in the pseudo-2D geometry. We studied several single-solid and binary mixtures to assess the reproducibility of segregation phenomena. The pseudo-2D model was able to predict the onset and minimum spouting flow rates of all mixtures with good accuracy. An analysis of the volume fraction contours of the binary mixtures permitted us to confirm that segregation phenomena were correctly predicted at low gas velocities. We showed that segregation decreased as the inlet gas flow rate was increased. Calculations performed in the complete 3D geometry were preliminarily assessed as more reliable but required almost four times as much computational time as those for the pseudo 2D geometry.

关键词： Spouted beds Computational fluid dynamics Discrete element method Binary mixtures Segregation phenomena

Biomechanical modeling of metal screw loadings on the human vertebra

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Acta Mechanica Sinica 2021年第2期37卷 307-320页

作者： Leonardo Molinari cristina Falcinelli Alessio Gizzi Alberto Di Martino Department of Engineering Campus Bio-Medico University of RomeVia A.del Portillo 21Rome 00128Italy Department of Biomedical and Neuromotor Science DIBINEM University of BolognaBolognaItaly 1st Orthopaedic and Traumatologic Clinic IRCCS Istituto Ortopedico RizzoliBolognaItaly

During spinal fusion surgery,angled screw insertion can provide a more favorable stress distribution reducing failure events(screw breakage and loosening).Finite element(FE)analysis can be employed for identifying the optimal insertion path,preventing stress concentrations,and ensuring a lower failure *** this work,a patient-specific FE model of L4 vertebra,virtually implanted with two pedicle screws,was obtained from diagnostic images and numerically *** elastic,inhomogeneous,and isotropic material properties were assigned to bone based on density distributions reconstructed from the medical *** mechanical response of the screws-vertebra system was analyzed through a progressive damage procedure,considering a stress-based *** screws insertion angles were simulated,as well as physiological loading *** each loading case,screw orientation influences the fracture mechanism(i.e.,brittle or ductile one),as well as the fracture pattern and ***,stresses in trabecular bone and pedicle screws are significantly affected by the screw *** caudomedial trajectory indicates the most safe case,significantly reducing the stress concentrations in both trabecular bone and *** findings aim to furnish a useful indication to surgeons regarding the screws insertion angle,further reducing the failure risk and improving the clinical outcome of the fixation procedure.

关键词： Fracture mechanics Patient-specific FE modeling Vertebra mechanics Screw orientation Stress analysis

Mechanisms of retinal neuroprotection of calcium dobesilate：therapeutic implications

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Neural Regeneration Research 2017年第10期12卷 1620-1622页

作者： Olga Simó-Servat cristina Solà-Adell Patricia Bogdanov cristina Hernández Rafael Simó Diabetes and Metabolism Research Unit Vall d'Hebron Research InstituteCIBERDEM(Instituto de Salud CarlosⅢ)BarcelonaSpain

Current treatments for diabetic retinopathy （DR） are based on laser photocoagulation and intravitreal injections of corti- costeroids or anti-vascular endothelial growth factor （VEGF） agents. These treatments are applicable only at advanced stages of the disease. In addition, they are expensive, require a vitreo- retinal specialist and are associated with significant adverse ef- fects. Therefore, new pharmacological treatments for the early stages of the disease are needed.

关键词： Ca Mechanisms of retinal neuroprotection of calcium dobesilate:therapeutic implications

源自巴西野生动物的毒液、毒素及其衍生物：药物开发的重要来源(英文)

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生理学报 2015年第3期67卷 261-270页

作者： Flavia De Marco Almeid Adriano monteiro de Castro Pimentat Monica cristina Oliveiral Maria Elena De Lima 米纳斯吉拉斯联邦大学药学院医药部制药技术实验室巴西米纳斯吉拉斯州贝洛奥里藏特31270-901 米纳斯吉拉斯联邦大学生物科学研究所生化和免疫学系动物毒液和毒素实验室巴西米纳斯吉拉斯州贝洛奥里藏特31270-901

在药物研发领域,野生动物的毒液正被广泛研究,许多基于毒液组分的研究以生物技术应用和专利申请形式被报道。巴西拥有丰富的生物多样性,公布的科研论文和专利申请数量显示了该资源是多么重要。本文报道了一份研究最透彻的巴西有毒动物... 详细信息

在药物研发领域,野生动物的毒液正被广泛研究,许多基于毒液组分的研究以生物技术应用和专利申请形式被报道。巴西拥有丰富的生物多样性,公布的科研论文和专利申请数量显示了该资源是多么重要。本文报道了一份研究最透彻的巴西有毒动物物种清单及从2000年到2013年的专利申请情况,包括源自巴西有毒物种的毒液成份、毒素及其衍生物。分析了涉及物种的数据、产品类型与发明者的国籍。55个专利申请涉及8个种属,响尾蛇、南美巨蝮蛇、矛头蝮蛇、斜蛛占其中78%。其余22%的专利来自巴西游走蛛、巴西金幽灵蝎、巴西捕鸟蛛、叶水蛙的毒液研究。大多数的发明(42%)包括抗癌、免疫调节剂或抗菌的药物,13%的发明为抗毒血清和疫苗,11%为降压成分,9%为镇痛及抗炎成分,其它25%为一些技术和试剂盒。巴西发明家占专利申请比重的49%,而其它国家如美国、德国、俄罗斯和法国同样发表了巴西动物毒液、毒素或衍生物的专利。虽然巴西拥有着大多数有毒物种的专利,但这些专利主要属于其学校和研究机构,药物工业在这方面依然薄弱。迄今为止,在世界范围内,已将巴西的有毒物种运用于药物研发,但大多数的物种可否作为研发的重要工具,仍然需要作进一步的勘探。

关键词：专利申请有毒物种毒液毒素药物研发

New neuroprotective perspectives in fighting oxidative stress and improving cellular energy metabolism by oleocanthal

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Neural Regeneration Research 2019年第7期14卷 1217-1218页

作者： cristina Angeloni Laura Giusti Silvana Hrelia School of Pharmacy University of Camerino Department of Clinical and Experimental Medicine University of Pisa Department for Life Quality Studies Alma Mater Studiorum-University of Bologna

Neurodegenerative diseases are a heterogeneous group of disorders characterized by a progressive dysfunction and death of neural cells which lead to compromised motor or cognitive ***,the loss of neuron is associated with both gliosis and,frequently,with abnormal accumulation of extracellular and intracellular filamentous deposit in specific cell *** a rapidly increasing aging population,these diseases are becoming a primary health problem(Albers and Beal,2000).

关键词： New neuroprotective fighting oxidative

Inflammatory bowel diseases: A disease (s) of modern times? Is incidence still increasing?

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World Journal of Gastroenterology 2008年第36期14卷 5491-5498页

作者： cristina Saro Gismera Beatriz Sicilia Aladrén Service of Digestive Diseases Hospital de Cabuees Gijón Spain Service of Digestive Diseases Alcaiz Hospital Spain

Inflammatory bowel diseases (IBD) are a heterogeneous group of diseases, not always easy to diagnose, even more difficult to classify, and diagnostic criteria are not always uniform. Well done population-based studies are not abundant, and so comparisons among different geographical areas or populations are not always very reliable. In this article, we have reviewed epidemiological studies available on the world’s population while making a critical review of published data.

关键词： Inflammatory bowel diseases Epidemiological Incidence Diagnostic criteria

Early social conditions affect female fecundity in hermaphrodites

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Current Zoology 2015年第6期61卷 983-990页

作者： Elio CANNARSA Mafia cristina LORENZI Gabriella SELLA Department of Life Sciences and Systems Biology Universita di Torino Via Accademia Albertina 13 10123 Torino Italy

Social conditions experienced prior to sexual maturity influence reproduction later in life in many animals. In simulta- neous hermaphrodites, variation in mating group size influences reproductive investment. As the mating group size increases, re- productive resources devoted to the female function decrease in favor of the male function. Prior to sexual maturity, many her- maphrodites have a protandrous phase during which they produce sperm and can fertilize hermaphrodites＇ eggs. In the simulta- neously hermaphroditic polychaete worm Ophryotrocha diadema, the cost of male reproduction during adolescence is spread over the whole energy budget of worms as shown by a reduced growth rate, a delayed age at sexual maturity and the shortening of life span compared to protandrous males that do not reproduce. Little is known on whether social conditions experienced dur- ing development affect reproductive investment of immature individuals. We investigated whether social conditions affected the length of the protandrous phase, body size and also the subsequent female fecundity of same-age protandrous individuals of O. diadema, which did not had to face competition for egg fertilization. Results show that in large group sizes protandrous males lengthened their protandrous phase, slowed down body growth and decreased their individual investment at the first egg laying compared to protandrous males that were reared in isolation. In the successive egg layings worms adjusted their egg output to the current social conditions. We interpreted these results as an indication that early social conditions represent a social stress result- ing in a reduction of the overall reproductive resources up to the first egg laying .

关键词： Social stress Early experience Ophryotrocha diadema Female fecundity Social environment

Potential roles of functional bacterial amyloid proteins,bacterial biosurfactants and other putative gut microbiota products in the etiopathogeny of Parkinson’s Disease

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BIOCELL 2021年第1期45卷 1-16页

作者： EMILIA MANOLE LAURA DUMITRESCU cristina NICULIȚE BOGDAN OVIDIU POPESCU LAURA cristina CEAFALAN Victor Babeș”National Institute of Pathology Bucharest050088Romania Colentina Clinical Hospital Bucharest020125Romania Carol Davila”University of Medicine and Pharmacy Bucharest020021Romania

An increasing number of studies provide evidence for the existence of a microbiota-gut-brain axis and its potential involvement in the development of sporadic Parkinson’s disease and other neurodegenerative *** neuropathologic hallmark of Parkinson’s disease is the presence of brain intraneuronal aggregates of misfolded alpha-synuclein,known as Lewy *** gut microbiota products may trigger alpha-synuclein conformational changes in the neurons of the enteric nervous system,which can then spread to the brain in a prion-like fashion through the vagus *** may interfere with neuroinflammatory pathways and susceptibility to *** this review,we assess the potential role of putative gut microbiota products in the etiopathogeny of Parkinson’s disease,with a special emphasis on functional bacterial amyloid proteins,bacterial biosurfactants,endotoxins and short-chain fatty *** possible roles of molecular hydrogen,a common byproduct of bacterial fermentation,are also addressed.

关键词： Alpha-synuclein Endotoxins Short-chain fatty acids