Modeling Dynamical Dark Energy

Cosmological models with different types of Dark Energy are becoming viable alternatives for standard models with the cosmological constant. Yet, such models are more difficult to analyze and to simulate. We present analytical approximations and discuss ways of making simulations for two families of models, which cover a wide range of possibilities and include models with both slow and fast changing ratio w=p\rho. More specifically, we give analytical expressions for the evolution of the matter density parameter Omega_m(z) and the virial density contrast Delta_c at any redshift z. The latter is used to identify halos and to find their virial masses. We also provide an approximation for the linear growth factor of linear fluctuations between redshift z=40 and z=0. This is needed to set the normalization of the spectrum of fluctuations. Finally, we discuss the expected behavior of the halo mass function and its time evolution.Comment: 10 pages, 10 figures ApJ submitte

A new perspective to model subsurface stratigraphy in alluvial hydrogeological basins, introducing geological hierarchy and relative chronology

This paper presents a novel perspective for modelling alluvial stratigraphy. It integrates the spatial geological information, geological maps and well-log descriptions, with the rules describing the hierarchy and relative chronology of the geological entities. As geological modelling tools are moving fast forward, the urgent need for expert geological input, codified as modelling rules, persists. Concerning subsurface alluvial architectures, the concepts of \u201cstratigraphic hierarchy\u201d and \u201crelative chronology\u201d provide the most relevant rules which permit to link the modelling procedure to the geo-history of a region. The paper shows how to formalize this knowledge into modelling rules. This is illustrated and implemented in a Python\u2122 module named HIEGEO which is applied on a 2-D cross-section from the Po Basin (N-Italy). The stratigraphic correlation yields 2-D pictures of the hierarchic stratigraphy and relative chronology of the units. The input are: an attribute table of stratigraphic boundaries expressing their hierarchy and chronology; contact points where these boundaries cross the control logs. Since the aim of HIEGEO is to illustrate the principle of the method but not to replace existing 3-D geological modelling tools, it implements a linear interpolation algorithm which creates joins between contact points. It plots linear joins framing polygons based on their hierarchy, at any user\u2019s desired detail. HIEGEO highlights potential inconsistencies of the input dataset, helping to re-evaluate the geological interpretation. The proposed workflow allows to: i) translate geological knowledge into modelling rules; ii) compute stratigraphic models constrained by the hierarchy of stratigraphic entities and the relative chronology of geological events; iii) represent internal geometries of the stratigraphic units, accounting for their composite nature; iv) reduce uncertainty in modelling alluvial architectures. It represents a starting point for multi-scale applications and could be easily integrated into 3-D modelling packages, to couple the hierarchical concept proposed here with existing advanced interpolation methods

Vibrational Mean Amplitudes of Methylamine and Dimethylamine

The mean amplitudes of vibration of methylamine and dimethylamine have been calculated from a previously reported Overlay Valence Force Field. Experimental and calculated C—N mean amplitudes for methylamine are compared and discussed

PARAMETRIC PARADIGMA: EXCEPTIONAL COFFERED CEILING ARCHITECTURE VS HBIM

The scientific community is confirming the advantages of using BIM in the processes of conservation, management, and intervention over architectural-historical heritage. However, many difficulties remain in the transcription process of elements of the built environment, especially when the objective of the model is to support decision-making processes in restoration operations. Even for apparently simple elements, the procedures are not trivial; the need to define the most adequate operational strategies remains. In the context of this study, a possible approach concerning the documentation of a coffered ceiling has been proposed, a case study which takes into consideration the need to discretize information (to make it effective, transmissible, and understandable) and the potential offered by the combined use of further software automatization

New working spaces. Policy perspectives before and after the COVID-19 pandemic

This chapter maps the debate of new working spaces (particularly CSs) on the level of European policy making. It explores how new working spaces have been interpreted by the European Commission and how this debate has evolved from its origins up to the recent COVID-19 period. For these purposes, two diferent ideas of CSs will be presented and discussed: CSs as innovation drivers boosting economic development; and as opportunities for territorial regeneration, such as brownfeld redevelopment or local hubs promoting social cohesion. Specifc attention is devoted to identifying the evolution of policies supporting these spaces with a focus on place-based and urban planning measures before and during the COVID-19 pandemic. This chapter empirically investigates this debate analyzing EU policy reports and case studies. Finally, remarks and suggestions for policy learning are presented

Prevalence of hepatitis B virus infections among blood donors in Federal Capital Territory, Abuja, Nigeria

Background: Transfusion of hepatitis B virus (HBV) infected blood represents a major but avoidable means of HBV transmission, which unfortunately still account for millions of global HBV infections annually.Method: This study determined the prevalence of HBV infection among 550 blood donors aged 18 to 60 years from selected hospitals and blood transfusion centres within the Federal Capital Territory, Nigeria, using hepatitis B surface antigen (HBsAg) rapid diagnostic test (RDT) kit and Enzyme linked Immuno-sorbent Assay (ELISA). Representative positive and negative samples for RDT and ELISA were tested by both conventional and real-time polymerase chain reaction (PCR) assayResults: Forty nine (8.9%) and 14 (2.8%) out of the 550 blood donors tested positive for HBsAg with the RDT and ELISA respectively. Replacement donors had higher prevalence rate of the HBV infection than voluntary donors. The highest prevalence of HBV infection was recorded among the 30–39 year age group. The difference in the rate of infection between the males and the females was not statistically significant (p>0.05). A perfect agreement between RDT and PCR and fair agreement between ELISA and PCR were observed.Conclusion: This study report a high prevalence of hepatitis B virus infections among blood donors in Abuja, Nigeria which underscores the need for proper screening of blood for transfusion to completely eliminate the incidence of transfusion transmitted HBV infections.Keywords: Blood, Malaria, Hepatitis, Rapid, Immuno-sorbent, Polymeras

Seismic vulnerability assessment method for vernacular architecture

The valorization and preservation of vernacular architecture, as well as traditional construction techniques and materials, is a key-element for cultural identity. As part of this essential objective, the present paper focuses on vernacular architecture earthquake preparedness. Earthquakes come unexpectedly, endangering in-use vernacular architecture and the population who inhabits it. However, conservation efforts are often mainly focused on historical construction and monuments. Furthermore, more detailed and sophisticated approaches typically used for monumental buildings require time, cost and resources that are not commonly assigned to the study of vernacular constructions. That is why the development of a simplified method for the seismic vulnerability assessment of vernacular architecture is of paramount importance. The paper firstly provides a brief overview of seismic vulnerability assessment methods, specifically the vulnerability index method, on which the proposed method is based. Then, the paper presents the procedure that was followed for the development of the seismic vulnerability assessment method for vernacular architecture proposed, which includes: (a) the identification and selection of constructive aspects and parameters that most influence the seismic behavior of the building; (b) the definition of the parameters seismic vulnerability classes by means of numerical parametric analysis using detailed finite element (FE) modeling and nonlinear static (pushover) analyses; and (c) the definition of the parameters weight, according to a statistical analysis performed on the results of the parametric study. Finally, the paper shows, as an example, the numerical strategy followed for the definition of the classes of one parameter.FEDER funds through the Competitivity and Internationalization Operational Programme–COMPETE and by national funds through FCT–Foundation for Science and Technology within the scope of the project POC1-01-0145-FEDER-007633.This work was also financed in the framework of the Portuguese Public Procurement Code,LOTE3EC5–Escola Secundária da Anadia e Gafanha da Nazar

Application of different classification methods for litho-fluid facies prediction: A case study from the offshore Nile Delta

In this work we test four classification methods for litho-fluid facies identification in a clastic reservoir located in offshore Nile Delta. The ultimate goal of this study is to find an optimal classification method for the area under examination. The geologic context of the investigated area allows us to consider three different facies in the classification: shales, brine sands and gas sands. The depth at which the reservoir zone is located (2300-2700 m) produces a significant overlap of the P- and S-wave impedances of brine sands and gas sands that makes the discrimination between these two litho-fluid classes particularly problematic. The classification is performed on the feature space defined by the elastic properties that are derived from recorded reflection seismic data by means of Amplitude Versus Angle (AVA) Bayesian inversion. As classification methods we test both deterministic and probabilistic approaches: the quadratic discriminant analysis and the neural network methods belong to the first group, whereas the standard Bayesian approach and the Bayesian approach that includes a 1D Markov chain prior model to constrain the vertical continuity of litho-fluid facies, belong to the second group. The capability of each method to discriminate the different facies is evaluated both on synthetic seismic data (computed on the basis of available borehole information) and on field seismic data. The outcomes of each classification method are compared with the known facies profile derived from well log data and the goodness of the results is quantitatively evaluated using the so called confusion matrix. It results that all methods return vertical facies profiles in which the main reservoir zone is correctly identified. However, the consideration of as much prior information as possible in the classification process is the winning choice to derive a reliable and a physically plausible predicted facies profile