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Analysis of the fluid-bed stability of FCC catalysts at high temperature in terms of bed elasticity

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Particuology 2008年第1期6卷 30-37页

作者： paola Lettieri Luca Mazzei Department of Chemical Engineering University College London Torrington Place London WC1E 7JE UK

The effect of temperature on the fluid-bed stability of three FCC catalysts has been analyzed through considerations on fluid-bed elasticity. Experimental findings on the effect of temperature on the elasticity modulus at minimum bubbling conditions, （E）mb, were analyzed using the hydrodynamic fluid-bed stability model developed by Foscolo and Gibilaro （1984） and adopting the interparticle-forces-based stability criterion developed by Mutsers and Rietema （1977）. For both models, the parameters which control changes in （E）mb with temperature are discussed, in order to establish the origin of the fluid-bed elasticity and analyze the ability of these models to discriminate between the relative importance of the hydrodynamic and interoarticle forces on the stability of the fluidized catalysts.

关键词： Fluidization FCC catalysts High temperature Stability Bed elasticity

Chemical composition and Zn bioavailability of the soil solution extracted from Zn amended variable charge soils

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Journal of Environmental Sciences 2010年第9期22卷 1398-1406页

作者： Mariavittoria Zampella paola Adamo Department of Soil Plant Environmental and Animal Production Sciences University of Naples Federico II

A study on variable charge soils （volcanic Italian and podzolic Scottish soils） was performed to investigate the influence of soil properties on the chemical composition of soil solution. Zinc speciation, bioavallability and toxicity in the soil solution were examined. The soils were spiked with increasing amounts of Zn （0, 100, 200, 400 and 1000 mg/kg） and the soil solutions were extracted using rhizon soil moisture samplers. The pH, total organic carbon （TOC）, base cations, anions, total Zn and free Zn^2＋ in soil solution were analysed. A rapid bioassay with the luminescent bacterium Escherichia coli HB 101 pUCD607 was performed to assess Zn toxicity. The influence of soil type and Zn treatments on the chemical composition of soil solution and on Zn toxicity was considered and discussed. Different trends of total and free Zn concentrations, base cations desorption and luminescence of E. coli HB 101 pUCD607 were observed. The soil solution extracted from the volcanic soils had very low total and free Zn concentrations and showed specific Zn^2＋/Ca^2＋ exchange. The soil solution from the podzolic soil had much higher total and free Zn concentrations and showed no evidence of specific Zn^2＋/Ca^2＋ exchange. In comparison with the subalkaline volcanic soils, the acidic podzol showed enhanced levels of toxic free Zn^2＋ and consequently stronger effects on E. coli viability.

关键词： rhizosamplers chemical speciation fractionation ecotoxicological test

Colon Adenocarcinoma in a Retrograde Intussusception: A Case Report and Literature Review

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Open Journal of Gastroenterology 2024年第5期14卷 153-160页

作者： Carlos Hernández Brito Pedro Arredondo Ruiz Brenda paola Sáenz Dávila Arsenio Torres Delgado Luis Eduardo Méndez Turrubiates Luis Ángel Amezcua Toledo Omar Josué Herrera López Surgical Oncology Department Centro Oncol&#243gico Onkolid Veracruz Mexico Clinical Oncology Department Centro Oncol&#243gico Onkolid Veracruz Mexico General and Laparoscopic Surgery Corporativo M&#233dico-Quir&#250rgico Torres Veracruz Mexico Radiation Oncology Department Centro Oncol&#243gico Onkolid Veracruz Mexico Radiology Department Centro Oncol&#243gico Onkolid Veracruz Mexico Anatomical Pathology Department Centro Oncol&#243gico Onkolid Veracruz Mexico

Background: Intussusception is defined as a telescoping of a proximal gastrointestinal segment with its mesentery to a distal one, only 5% occur in adults and in colon the probability that it is caused by a malignant disease is up to 65%. Only 1% occurs in a retrograde manner, the rest occur in an anterograde manner. Aim: Describe the clinical presentation of an intussusception in the adult patient as well as its most frequent causes and possible complications that influence decision making for a definitive treatment. Case Presentation: A 66-year-old woman diagnosed with colon adenocarcinoma who underwent elective transverse colectomy and colonic anastomosis with an incidental finding of a transverse colon tumor in a retrograde intussusception was studied. Conclusion: In any adult patient with an intussusception especially in colon a neoplasia should be suspected and the affected segment should be resected without being reduced due to the risk of perforation and tumor dissemination.

关键词： Colon Cancer Colon Adenocarcinoma Colonic Intussusception Intussusception

Extreme Cities and Bad Places

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International Journal of Disaster Risk Science 2012年第1期3卷 3-10页

作者： paola Viganò Department of Urbanism University IUAV of Venice(Istituto Universitario di Architettura di Venezia)30125 VeniceItaly

This article considers places where climate change-induced hazards will be particularly important,focusing on two examples,the lagoon location of Venice and the Garonne riverbank location of Bordeaux. The Venice lagoon territory is close to the coast and has a dispersed form of urban development. Our project experiments resulted in the formulation of a series of adaptation strategies to increased disaster risks,including returning current agricultural land and residential areas to their original state as wetlands and marshes before their reclamation during the early decades of the twentieth century. The scenarios introduce space as a relevant variable into the debate about the impact of climate change and adaptation. This article also deals with the recovery of “bad places,” such as the urban blight on the Garonne riverbanks of Bordeaux,and their relationship with sustainability and disaster risks. Increasingly,the emphasis on minimizing energy consumption and promoting recycling forces cities to reuse places of elevated risk. Only very recently in modern urban planning are polluted and risky areas frequently selected for new development projects to reclaim the vast areas of existing brownfields in the name of sustainability. Integrating disaster risk reduction into a new economic and social context has thus become an extremely important part of contemporary urban design and planning for these reclaimed(bad) areas. The research concludes that urban and territorial design should and can integrate the inevitability of risk. This is necessary for developing approaches and strategies that offer some rethinking about “wicked” problems,long-term time horizons,radical imagination,dynamic representations,and minute territorial readings in contemporary urban planning.

关键词： disaster urban contemporary

Genetic predisposition to pancreatic cancer

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World Journal of Gastroenterology 2014年第31期20卷 10778-10789页

作者： paola Ghiorzo Department of Internal Medicine and Medical Specialties University of Genoa and IRCCS Azienda Ospedaliera Universitaria San Martino-IST Istituto Nazioanle per la Ricerca sul Cancro 16132 Genoa Italy

Pancreatic adenocarcinoma(PC) is the most deadly of the common cancers. Owing to its rapid progression and almost certain fatal outcome, identifying individuals at risk and detecting early lesions are crucial to improve outcome. Genetic risk factors are believed to play a major role. Approximately 10% of PC is estimated to have familial inheritance. Several germline mutations have been found to be involved in hereditary forms of PC, including both familial PC(FPC) and PC as one of the manifestations of a hereditary cancer syndrome or other hereditary conditions. Although most of the susceptibility genes for FPC have yet to be identified, next-generation sequencing studies are likely to provide important insights. The risk of PC in FPC is sufficiently high to recommend screening of high-risk individuals; thus, defining such individuals appropriately is the key. Candidate genes have been described and patients considered for screening programs under research protocols should first be tested for presence of germline mutations in the BRCA2, PALB2 and ATM genes. In specific PC populations, including in Italy, hereditary cancer predisposition genes such as CDKN2 A also explain a considerable fraction of FPC.

关键词： Pancreatic adenocarcinoma Susceptibility genes CDKN2A Melanoma Hereditary cancer syndromes Screening

Expectations and Level of Satisfaction of the Patient with Parkinson’s Disease Undergoing Deep Brain Stimulation Surgery at the National Institute of Neurology and Neurosurgery

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Advances in Parkinson's Disease 2024年第1期13卷 1-7页

作者： paola Bazán-Rodríguez Eduardo Ichikawa-Escamilla Etienne Reséndiz-Henríquez Carlos E. Martínez-Cortés Amin Cervantes-Arriaga Mayela Rodríguez-Violante Lisette Bazán-Rodríguez Laboratorio de Enfermedades Neurodegenerativas en el Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suarez Ciudad de México México Laboratorio de Enfermedades Neurodegenerativas en el Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suarez Ciudad de México México. Unidad Periférica para el Estudio de la Neuroinflamación en Patologías Neurológicas del Instituto de Investigaciones Biomédicas en el Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suarez Ciudad de México México

Background: Deep brain stimulation (DBS) is an established treatment for patients with advanced Parkinson’s disease (PD). Reports show continued patient satisfaction after surgery despite not maintaining clinical improvement as measured by evolution scales. Objectives: The present study sought to explore expectations and level of satisfaction in patients after DBS surgery with a semi-structured questionnaire and subsequent correlation with functional scales, Quality of Life (QoL), and motor and non-motor symptoms. Methods: We performed descriptive statistics to represent demographic data, Wilcoxon rank tests to determine significant differences, and Spearman correlation between the applied scales. Results: We evaluated 20 patients with a history of DBS surgery. 45% were female, with a mean age of 55.7 ± 14.15 years, a mean disease duration of 13.42 ± 8.3 years, and a mean time after surgery of 3.18 ± 1.86 years. Patients reported surgery meeting expectations in 85.5% and continued satisfaction in 92%. These two variables showed a significant correlation. Conclusions: This sample of patients remained satisfied after DBS surgery, although we found no differences in motor and non-motor clinimetric scales. Further studies are needed to confirm the importance of assessing quality of life in patients with DBS.

关键词： Parkinson’s Disease Quality of Life Deep Brain Stimulation Patient Satisfaction

Plant virus-derived siRNAs“turn on”broad-spectrum plant immunity in wheat

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Molecular Plant 2021年第7期14卷 1038-1040页

作者： paola Leonetti Vitantonio Pantaleo Department of Biology Agricultural and Food SciencesInstitute for Sustainable Plant ProtectionBari UnitCNRBari 70126Italy

Viruses are the most abundant biological entities on Earth and the major carriers of disease and mortality as well as the drivers of global *** plant viruses potentially influence global processes is an emergent issue,particularly for their putative implications in *** infection and spread,plant viruses are capable of reprogramming host gene expression via RNA silencing by releasing viral suppressors of RNA silencing,viral small interfering RNAs(vsiRNAs),and by inducing the production of viral-associated small interfering RNAs(va-siRNAs).Recently,studies on various crop-virus pathosystems suggest that RNA silencing suppressors(RSSs)。

关键词： immunity mortality releasing

Minimal Free Resolutions of Zero-dimensional Schemes in P1 ×P1

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Algebra Colloquium 2015年第1期22卷 97-108页

作者： paola Bonacini Lucia Marino Universita degli Studi di Catania ViMe A. Doria 6 95125 Catania Italy

Let X be a zero-dimensional scheme in p1 × p1. Then X has a minimal free resolution of length 2 if and only if X is ACM. In this paper we determine a class of reduced schemes whose resolutions, similarly to the ACM case, can be obtained by their Hilbert functions and depend only on their distributions of points in a grid of lines. Moreover, a minimal set of generators of the ideal of these schemes is given by curves split into the union of lines.

关键词： resolution Hilbert function separators

Thermal survival limits of young and mature larvae of a cold stenothermal chironomid from the Alps （Diamesinae： Pseudodiamesa branickii [Nowicki, 1873]）

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Insect Science 2017年第2期24卷 314-324页

作者： Valeria Lencioni paola Bernabo Section of Invertebrate Zoology and Hydrobiology MUSE-Museo delle Scienze Corso del Lavoro e della Scienza 3 38123 Trento Italy

The threats posed by climate change make it important to expand knowl- edge concerning cold and heat tolerance in stenothermal species from habitats potentially threatened by temperature changes. Thermal limits and basal metabolism variations were investigated in Pseudodiamesa branickii （Diptera： Chironomidae） under thermal stress between -20 and 37 ℃. Supercooling point （SCP）, lower （LLTs） and upper lethal temper- atures （ULTs）, and oxygen consumption rate were measured in overwintering young （lst and 2nd instar） and mature （3rd and 4th instar） larvae from an Alpine glacier-fed stream. Both young and mature larvae were freezing tolerant （SCPs = -7.1 ℃ and -6.4 ℃, re- spectively; LLT100 〈SCP and 〉 -20 ℃） and thermotolerant （ULTso = 31.7 ± 0.4, 32.5± 0.3, respectively）. However, ontogenetic differences in acute tolerance were observed. The LLT50 calculated for the young larvae （=-7.4 ℃） was almost equal to their SCP （= -7.1 ℃） and the overlapping of the proportion of mortality curve with the CPIF curve highlighted that the young larvae are borderline between freezing tolerance and freezing avoidance. Furthermore, a lower ULT100 in the young larvae （of ca. 1 ℃）, suggests that they are less thermotolerant than mature larvae. Finally, young larvae exhibit a higher oxygen consumption rate （mgO2/gAFDM/h） at any temperature tested and are overall less resistant to oxygen depletion compared to mature larvae at ≥ 10 ℃. These findings sug- gest that mature larvae enter into a dormant state by lowering their basal metabolism until environmental conditions improve in order to save energy for life cycle completion during stressful conditions.

关键词： basal metabolism glacier-fed streams larval development supercooling point thermotolerance