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Accelerated Carbonation Assessment of High-Volume Fly Ash Concrete

Journal of Materials Science and Chemical Engineering 2020年第3期8卷 23-38页

作者： federico aguayo Anthony Torres Yoo-Jae Kim Omkar Thombare Texas State University San Marcos TX USA

The issue of concrete carbonation has gained importance in recent years due to the increase use in supplementary cementing materials (SCMs) in concrete mixtures. While there is general agreement that concrete carbonation progresses at maximum at a relative humidity of about 60%, the rate may differ in the case of cements blended with SCMs, especially with high-volume fly ash replacements. In this study, the effect of high-volume fly ash concrete exposed to low ambient relative humidity (RH) conditions (57%) and accelerated carbonation (4% CO2) is investigated. Twenty-three concrete mixtures were produced varying in cementitious contents (310, 340, 370, and 400 kg/m3), water-to-cementitious materials ratio (0.45 and 0.50), and fly ash content (0%, 15%, 30%, and 50%) using a low and high-calcium fly ash. The specimens were allowed 1 and 7 days of moist curing and monitored for their carbonation rate and depth through phenolphthalein measurements up to 105 days of exposure. The accelerated carbonation test results indicated that increasing the addition of fly ash also led to increasing the depth of carbonation. Mixtures incorporating high-calcium fly ash were also observed to be more resistant against carbonation than low-calcium fly ash due to the higher calcium oxide (CaO) content. However, mixtures incorporating high-volume additions (50%) specimens were fully carbonated regardless of the type of fly ash used. It was evident that the increase in the duration of moist curing from 1 day to 7 days had a positive effect, reducing the carbonation depth for both plain and blended fly ash concrete mixes, however, this effect was minimal in high-volume fly ash mixtures. The results demonstrated that the water-to-cementitious ratio (W/CM) had a more dramatic impact on carbonation resistance than the curing age for mixtures incorporating 30% or less fly ash replacement, whereas those mixtures incorporating 50% showed minor differences regardless of curing age or W/CM. Based o

关键词： Accelerated Carbonation Fly Ash Concrete Relative Humidity High-Volume Fly Ash Supplementary Cementitious Materials

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Developing High Strength Pervious Concrete Mixtures with Local Materials

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Journal of Materials Science and Chemical Engineering 2020年第1期8卷 20-34页

作者： Anthony Torres federico aguayo Cristian Gaedicke Parker Nerby Mario Cavazos Collin Nerby Texas State University San Marcos TX USA California State University-East Bay Hayward CA USA

This study focuses on developing pervious concrete mixtures that have higher compressive strengths than conventional pervious concrete. This study also focuses on producing high strength pervious concrete that is also made with locally available materials. The study focused on four aspects of pervious concrete to produce high compressive strengths. These parameters were the effect of the coarse aggregate (type and size), the compaction of the test specimens, the effect of the w/c along with superplasticizers, and lastly the effect of silica fume. This study was completed parametrically in order to isolate each variable in order to see its individual affect. Once an optimum performance was obtained from one variable the best performing mixture was used for the next variable testing. This method allowed for the highest performing mixture to be obtained from each of the investigated variables. The results showed that high strength pervious concrete made with local aggregates, without polymers, and without fibers can be produced in the range of 15.44 MPa - 21.63 MPa. A porosity range 19.1% - 32.9% with a percolation rate range of 5.8 mm/s - 1.9 mm/s was also achieved, with a porosity of 19.4% and percolation rate of 2.6 mm/s for the highest performing mixture.

关键词： Pervious Concrete High Strength Compressive Strength Local Materials Sustainable

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CBE Clima Tool:A free and open-source web application for climate analysis tailored to sustainable building design

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Building Simulation 2024年第3期17卷 493-508页

作者： Giovanni Betti federico Tartarini Christine Nguyen Stefano Schiavon Center for the Built Environment University of California BerkeleyBerkeleyUSA Berkeley Education Alliance for Research in Singapore SingaporeSingapore Heat and Health Research Incubator Faculty of Medicine and HealthThe University of SydneyCamperdownAustralia College of Letters and Sciences University of California BerkeleyBerkeleyUSA

Climate-responsive building design holds immense potential for enhancing comfort,energy efficiency,and environmental ***,many social,cultural,and economic obstacles might prevent the wide adoption of designing climate-adapted *** of these obstacles can be removed by enabling practitioners to easily access,visualize and analyze local climate *** CBE Clima Tool(Clima)is a free and open-source web application that offers easy access to publicly available weather files and has been created for building energy simulation and *** provides a series of interactive visualizations of the variables contained in the EnergyPlus Weather Files and several derived ones like the UTCI or the adaptive comfort *** is aimed at students,educators,and practitioners in the architecture and engineering *** its inception,Clima’s user base has exhibited robust growth,attracting over 25,000 unique users annually from across 70 *** tool is poised to revolutionize climate-adaptive building design,transcending geographical boundaries and fostering innovation in the architecture and engineering fields.

关键词： architectural design climate analysis sustainable building design web application building energy simulation open-source software

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Navigating the autophagic landscape:Epigenetic modulation in gastrointestinal cancer

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World Journal of Gastroenterology 2024年第31期30卷 3628-3634页

作者： Davide Ramoni federico Carbone Fabrizio Montecucco Department of Internal Medicine University of GenoaGenoa 16132Italy Department of Internal Medicine University of Genoa and IRCSS Policlinico San MartinoGenoa 16132Italy

This editorial comments on the manuscript by Chang et al,focusing on the still elusive interplay between epigenetic regulation and autophagy in gastrointestinal diseases,particularly ***,essential for cellular homeostasis,exhibits diverse functions ranging from cell survival to death,and is particularly implicated in physiological gastrointestinal cell ***,its role in pathological backgrounds remains intricate and *** underscore the dual nature of autophagy in cancer,where its early suppressive effects in early stages are juxtaposed with its later promotion,contributing to *** discrepancy is attributed to the dysregulation of autophagy-related genes and their intricate involvement in cellular *** modifications and regulations of gene expression,including non-coding RNAs(ncRNAs),emerge as critical players in exerting regulatory control over autophagy flux,influencing treatment responses and tumor *** epigenetic mechanisms and improving strategies involving the inhibition or induction of autophagy through pharmacological or genetic means present potential avenues to sensitize tumor cells to ***,nanocarrier-based delivery of ncRNAs offers innovative therapeutic *** the intricate interaction between autophagy and ncRNA regula-tion opens avenues for the development of targeted therapies,thereby improving the prognosis of gastrointestinal malignancies with poor outcomes.

关键词： Epigenetic regulation Autophagy Gastrointestinal cancer Non-coding RNAs Target therapies

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Stable diffusion gradients in microfluidic conduits bounded by fluid walls

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Microsystems & Nanoengineering 2024年第3期10卷 357-367页

作者： federico Nebuloni Cyril Deroy Peter R.Cook Edmond J.Walsh Department of Engineering Science Osney Thermo-Fluids InstituteUniversity of OxfordOxford OX20ESUK Sir William Dunn School of Pathology University of OxfordOxford OX13REUK

Assays mimicking in vitro the concentration gradients triggering biological responses like those involved in fighting infections and blood clotting are essential for biomedical *** assays prove especially attractive as they allow precise control of gradient shape allied to a reduction in *** microfluidic devices are fabricated using solid plastics that prevent direct access to responding ***-walled microfluidics allows the manufacture of circuits on standard Petri dishes in seconds,coupled to simple operating methods;cell-culture medium sitting in a standard dish is confined to circuits by fluid walls made of an immiscible *** develop and experimentally validate an analytical model of diffusion between two or more aqueous streams flowing at different rates into a fluid-walled conduit with the cross-section of a circular *** solid walls,fluid walls morph during flows as pressures fall,with wall shape changing down the *** model is validated experimentally for Fourier numbers<0.1 using fluorescein diffusing between laminar *** enables a priori prediction of concentration gradients throughout a conduit,so allowing rapid circuit design as well as providing bioscientists with an accurate way of predicting local concentrations of bioactive molecules around responsive and nonresponsive cells.

关键词： walls diffusion attractive

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Facing ethical concerns in the age of precise gene therapy:Outlook on inherited arrhythmias

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World Journal of Cardiology 2024年第2期16卷 64-66页

作者： federico Carbone Fabrizio Montecucco Department of Internal Medicine University of GenoaGenoa 16132Italy IRCCS Ospedale Policlinico San Martino Genoa Italian Cardiovascular NetworkGenoa 16132Italy

This editorial,comments on the article by Spartalis et al published in the recent issue of the World Journal of *** here provide an outlook on potential ethical concerns related to the future application of gene therapy in the field of inherited *** monogenic diseases with no or few therapeutic options available through standard care,inherited arrhythmias are ideal candidates to gene therapy in their *** with inherited arrhythmias typically have a poor quality of life,especially young people engaged in agonistic *** genome editing for treatment of inherited arrhythmias still has theoretical application,advances in CRISPR/Cas9 technology now allows the generation of knock-in animal models of the ***,clinical translation is somehow expected soon and this make consistent discussing about ethical concerns related to gene editing in inherited *** off-target activity is a known technical issue,but its relationship with ethnical and individual genetical diversity raises concerns about an equitable ***,the costeffectiveness may further limit an equal distribution of gene *** economic burden of gene therapies on healthcare systems is is increasingly recognized as a pressing concern.A growing body of studies are reporting uncertainty in payback periods with intuitive short-term effects for insurance-based healthcare systems,but potential concerns for universal healthcare systems in the long term as ***,those aspects strongly indicate a need of regulatory entities to manage those issues.

关键词： Ethics Inherited arrhythmias CRISPR/Cas9 Gene therapy Equitable accessibility

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Developing Sustainable Ultra High Strength Concrete Mixtures Using Spent Foundry Sand

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Journal of Civil Engineering and Architecture 2019年第6期13卷 343-352页

作者： Anthony Torres federico aguayo Srinivas Allena Department of Engineering Technology Texas State UniversitySan Marcos 78666TexasUSA Department of Civil Engineering Cleveland State UniversityCleveland 44115OhioUSA

This study presents the development of ultra high strength concrete(UHSC)that has been made more sustainable by using both local materials from central Texas and spent foundry sand(FS)from the metal casting industry,which has also been obtained *** study first describes various trial mixtures tested as well as the specimen preparation techniques investigated that led to the final UHSC-FS *** developed mixtures were proportioned with local constituents to increase the sustainable impact of the material by reducing emissions due to shipping as well as making UHSC more affordable to a wider variety of *** final mixture design constituents were:river sand,locally available type I/II cement,silica fume,and spent FS,which was obtained from a local steel casting *** variables were investigated,such as the aggregate type and size,concrete age(7,14,and 28-days),the curing regimen,and the water-to-cement ratio(w/cm)to optimize a UHSC mixture that used local materials and *** systematic development revealed that heat curing the specimens in a water bath at 50 oC(122 oF)after demolding and then dry curing at 200 oC(392 oF)two days before testing with a w/cm of 0.20 at 28-days produced the highest compressive *** an optimum UHSC mixture was identified a partial replacement of the fine aggregate with FS was completed at 10%,20%,and 30%.The results showed an increase of compressive strength performance at 10%replacement,followed by no change at 20%,and finally a slight decrease at 30%.Developing this innovative material with local materials and FS ultimately produces a novel sustainable construction material,reduces the costs,and produces mechanical performance similar to prepackaged,commercially,available construction building materials.

关键词： High strength concrete sustainability recycled concrete aggregate local products construction materials

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Coated boron layers by boronization and a real-time boron coating using an impurity powder dropper in the LHD

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Plasma Science and Technology 2024年第8期26卷 25-31页

作者： Naoko ASHIKAWA Robert LUNSFORD federico NESPOLI Erik GILSON Yaowei YU Jiansheng HU Shinichiro KADO National Institute for Fusion Science Toki 509-5292Japan Princeton Plasma Physics Laboratory Princeton NJ 08540United States of America Institute of Plasma Physics Chinese Academy of SciencesHefei 230031People’s Republic of China Institute of Advanced Energy Kyoto UniversityKyoto 611-0011Japan

In the Large Helical Device(LHD),diborane(B2H6)is used as a standard boron source for boronization,which is assisted by helium glow *** 2019,a new Impurity Powder Dropper(IPD)system was installed and is under evaluation as a real-time wall conditioning *** the LHD,which is a large-sized heliotron device,an additional helium(He)glow discharge cleaning(GDC)after boronization was operated for a reduction in hydrogen recycling from the coated boron *** operational time of 3 h was determined by spectroscopic data during glow discharges.A flat hydrogen profile is obtained on the top surface of the coated boron on the specimen exposed to *** results suggest a reduction in hydrogen at the top surface by *** oxygen in coated boron was obtained by boronization,and the coated boron,which has boron-oxide,on the first wall by B-IPD was also *** the difference in coating areas between B2H6 boronization and B-IPD operation,it would be most effective to use the IPD and B2H6 boronization coating together for optimized wall conditioning.

关键词： boron layer oxygen impurity hydrogen recycling impurity powder dropper LHD EAST

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The Effect of Various Polynaphthalene Sulfonate Based Superplasticizers on the Workability of Reactive Powder Concrete

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Journal of Building Material Science 2020年第1期2卷 24-29页

作者： Anthony Torres federico aguayo Srinivas Allena Michael Ellis Texas State University San MarcosTX78666 Cleveland State University Cleveland44115

A superplasticizer is a type of chemical admixture used to alter the workability(viscosity)of fresh *** workability of fresh concrete is often of particular importance when the water-to-cement(w/c)ratio is low and a particular workability is *** Powder Concrete(RPC)is a high-strength concrete formulated to provide compressive strengths exceeding 130MPa and made of primarily *** materials typically have a very low w/c,which requires the use of a chemical admixture in order to create a material that is easier to place,handle and *** are commonly used for this *** are developed from different formulations,the most common being Polycarboxylate Ether(PCE),Polymelamine Sulfonate(PMS),and Polynaphthalene Sulfonate(PNS).This study investigates the effect of various PNS based superplasticizers on the rheological performance and mechanical(compressive strength)performance of a RPC *** distinctive types of PNS based superplasticizers were used;three of various compositional strengths(high,medium,low range)from a local provider,and three of the same compositional strengths(high,medium,low)from a leading *** properties investigated were the individual superplasticizers’viscosity,the concrete workability,determined through a mortar spread test,the concrete viscosity,and the compressive strength of the hardened RPC mixtures measured at 7,14,and 28 *** separate RPC mixtures were prepared,which contained two different water-to-cementitious ratios,which consequently increases the dosage of superplasticizer needed,from 34.8L/m3 to 44.7L/*** results show that the name brand high range composition produced the overall highest spread,lowest viscosity,and a highest compressive ***,the local provider outperformed the name brand in the mid and low range ***,the rheology assessment also confirmed that the name brand high range,and RPC fabricated with the n

关键词： Reactive powder concrete Ultra high strength concrete Superplasticizer Workability

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Ultrasound unveiling:Decoding venous congestion in heart failure for precision management of fluid status

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World Journal of Cardiology 2024年第6期16卷 306-309页

作者： Davide Ramoni federico Carbone Fabrizio Montecucco Department of Internal Medicine University of GenoaGenoa 16132Italy Department of Internal Medicine IRCCS Ospedale Policlinico San MartinoGenoa 16132Italy

This editorial discusses the manuscript by Di Maria et al,published in the recent issue of the World Journal of *** here focus on the still elusive pathophysiological mechanisms underlying cardio-renal syndrome(CRS),despite its high prevalence and the substantial worsening of both kidney function and heart *** the measure of right atrial pressure through right cardiac catheterization remains the most accurate albeit invasive and costly procedure,integrating bedside ultrasound into diagnostic protocols may substantially enhance the staging of venous congestion and guide therapeutic *** particular,with the assessment of Doppler patterns across multiple venous districts,the Venous Excess Ultrasound(VExUS)score improves the management of fluid overload and provides insight into the underlying factors contributing to cardio-renal *** specific echocardiographic parameters,particularly those concerning the right heart,may thus improve the VExUS score sensitivity,offering perspective into the nuanced comprehension of cardio-renal dynamics.A multidisciplinary approach that consistently incorporates the use of ultrasound is emerging as a promising advance in the understanding and management of CRS.

关键词： Cardio-renal syndrome Fluid overload Heart failure Ultrasound assessment Venous congestion Venous excess ultrasound score

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