The single-station microtremor horizontal-to-vertical spectral ratio (MHVSR) method was initially proposed to retrieve the site amplification function and its resonance frequencies produced by ...unconsolidated sediments overlying high-velocity bedrock. Presently, MHVSR measurements are predominantly conducted to obtain an estimate of the fundamental site frequency at sites where a strong subsurface impedance contrast exists. Of the earthquake site characterization methods presented in this special issue, the MHVSR method is the furthest behind in terms of consensus towards standardized guidelines and commercial use. The greatest challenges to an international standardization of MHVSR acquisition and analysis are (1) the
what
— the underlying composition of the microtremor wavefield is site-dependent, and thus, the appropriate theoretical (forward) model for inversion is still debated; and (2) the
how
— many factors and options are involved in the data acquisition, processing, and interpretation stages. This paper reviews briefly a historical development of the MHVSR technique and the physical basis of an MHVSR (the
what
). We then summarize recommendations for MHVSR acquisition and analysis (the
how
). Specific sections address MHVSR interpretation and uncertainty assessment.
The National Institutes of Health (NIH)-funded Diversity Program Consortium (DPC) includes a Coordination and Evaluation Center (CEC) to conduct a longitudinal evaluation of the two signature, ...national NIH initiatives - the Building Infrastructure Leading to Diversity (BUILD) and the National Research Mentoring Network (NRMN) programs - designed to promote diversity in the NIH-funded biomedical, behavioral, clinical, and social sciences research workforce. Evaluation is central to understanding the impact of the consortium activities. This article reviews the role and function of the CEC and the collaborative processes and achievements critical to establishing empirical evidence regarding the efficacy of federally-funded, quasi-experimental interventions across multiple sites. The integrated DPC evaluation is particularly significant because it is a collaboratively developed Consortium Wide Evaluation Plan and the first hypothesis-driven, large-scale systemic national longitudinal evaluation of training programs in the history of NIH/National Institute of General Medical Sciences.
To guide the longitudinal evaluation, the CEC-led literature review defined key indicators at critical training and career transition points - or Hallmarks of Success. The multidimensional, comprehensive evaluation of the impact of the DPC framed by these Hallmarks is described. This evaluation uses both established and newly developed common measures across sites, and rigorous quasi-experimental designs within novel multi-methods (qualitative and quantitative). The CEC also promotes shared learning among Consortium partners through working groups and provides technical assistance to support high-quality process and outcome evaluation internally of each program. Finally, the CEC is responsible for developing high-impact dissemination channels for best practices to inform peer institutions, NIH, and other key national and international stakeholders.
A strong longitudinal evaluation across programs allows the summative assessment of outcomes, an understanding of factors common to interventions that do and do not lead to success, and elucidates the processes developed for data collection and management. This will provide a framework for the assessment of other training programs and have national implications in transforming biomedical research training.
Background
: Geospatial linked data brings into the scope of the Semantic Web and its technologies, a wealth of datasets that combine semantically-rich descriptions of resources with their ...geo-location. There are, however, various Semantic Web technologies where technical work is needed in order to achieve the full integration of geospatial data, and federated query processing is one of these technologies.
Methods
: In this paper, we explore the idea of annotating data sources with a bounding polygon that summarizes the spatial extent of the resources in each data source, and of using such a summary as an (additional) source selection criterion in order to reduce the set of sources that will be tested as potentially holding relevant data. We present our source selection method, and we discuss its correctness and implementation.
Results
: We evaluate the proposed source selection using three different types of summaries with different degrees of accuracy, against not using geospatial summaries. We use datasets and queries from a practical use case that combines crop-type data with water availability data for food security. The experimental results suggest that more complex summaries lead to slower source selection times, but also to more precise exclusion of unneeded sources. Moreover, we observe the source selection runtime is (partially or fully) recovered by shorter planning and execution runtimes. As a result, the federated sources are not burdened by pointless querying from the federation engine.
Conclusions
: The evaluation draws on data and queries from the agroenvironmental domain and shows that our source selection method substantially improves the effectiveness of federated GeoSPARQL query processing.
In this paper, the variational multiscale interpolating element-free Galerkin (VMIEFG) method is developed to obtain the numerical solution ofthenonlinearDarcy–Forchheimer model. We use the ...interpolating moving least squares method instead of the moving least squares approximation to construct meshless shape functions with delta function properties. Then the flux boundary condition of the Darcy–Forchheimer model can be handled easily. Hughes’ variational multiscale (HVM) method is applied to overcome the numerical oscillation caused by equal-order basis for the velocity and pressure. Moreover, the HVM ensures that the resultant formulation in the VMIEFG method is consistent and the stabilization parameter (or tensor) appears naturally. Consequently, the stabilization parameter is free of user-defined. The fixed point iteration method is used to deal with the nonlinear term. Some numerical examples are provided to illustrate the stability and performance of the proposed method for solving the nonlinear Darcy–Forchheimer model.
•Localized Trefftz collocation scheme is proposed for heat conduction analysis.•Generalized reciprocity method is proposed to deal with the nonhomogeneous terms.•The proposed method inherits ...semi-analytical property and avoids dense matrix.•A large-scale simulation with almost 100,000 discretization nodes is performed.
This paper presents a novel localized collocation Trefftz method (LCTM) for heat conduction analysis in two kinds of heterogeneous materials (functionally graded materials and multi-medium materials) under temperature loading. In contrast to the conventional collocation Trefftz method (CTM), the proposed LCTM divides the whole domain into many stencil support domains consisting of several discretization nodes. An efficient technique, the generalized reciprocity method (GRM), is proposed to derive the problem-dependent T-complete functions for approximating the particular solution of the nonhomogeneous equations in the stencil support domains. Based on the moving least square (MLS) technique and T-complete functions, the LCTM numerical differentiation formulation at a certain node can be derived by using a linear combination of the T-complete functions at its adjacent discretization nodes in the related stencil support domain. It inherits the semi-analytical property from the conventional CTM and avoids the ill-conditioned dense matrix problem. Besides, the quadrant criterion is applied to guarantee the stability of the proposed LCTM, and the domain decomposition method (DDM) is introduced to divide the multi-medium domains into several single-medium sub-domains. Numerical results demonstrate the accuracy and efficiency of the proposed LCTM in comparison with the known analytical solutions and the finite element method (FEM) results.
Ceftriaxone is a cephalosporin antibiotic drug used as first-line treatment for a number of bacterial diseases. Ceftriaxone belongs to the third generation of antibiotics and is available as an ...intramuscular or intravenous injection. Previously published pharmacokinetic studies have used high-performance liquid chromatography coupled with ultraviolet detection (HPLC-UV) for the quantification of ceftriaxone. This study aimed to develop and validate a bioanalytical method for the quantification of ceftriaxone in human plasma using liquid chromatography followed by tandem mass spectrometry (LC-MS/MS). Sample preparation was performed by protein precipitation of 100 µl plasma sample in combination with phospholipid-removal techniques to minimize matrix interferences. The chromatographic separation was performed on an Agilent Zorbax Eclipse Plus C18 column with 10 mM ammonium formate containing 2% formic acid: acetonitrile as mobile phase at a flow rate of 0.4 ml/min with a total run time of 10 minutes. Both the analyte and cefotaxime (internal standard) were quantified using the positive electrospray ionization (ESI) mode and selected reaction monitoring (SRM) for the precursor-product ion transitions
m/z
555.0→396.1 for ceftriaxone and 456.0→324.0 for cefotaxime. The method was validated over the concentration range of 1.01-200 μg/ml. Calibration response showed good linearity (correlation coefficient > 0.99) and matrix effects were within the ±15% limit in 6 different lots of sodium heparin plasma tested. However, citrate phosphate dextrose plasma resulted in a clear matrix enhancement of 24% at the low concentration level, which was not compensated for by the internal standard. Different anticoagulants (EDTA, heparin and citrate phosphate dextrose) also showed differences in recovery. Thus, it is important to use the same anticoagulant in calibration curves and clinical samples for analysis. The intra-assay and inter-assay precision were less than 5% and 10%, respectively, and therefore well within standard regulatory acceptance criterion of ±15%.
This paper discusses the numerical solutions of the nonlinear Klein–Gordon–Zakharov model by the use of five recent numerical schemes (Adomian decomposition, El‐kalla, cubic B‐spline, extended cubic ...B‐spline, and exponential cubic B‐spline). The object of this numerical analysis is to demonstrate the accuracy of the analytical solutions obtained using the generalized Khater system and also to display the accuracy of the five numerical schemes mentioned above. This mathematical model explains the development in plasma physics of efficient Langmuir turbulence. We use computational solutions to assess the original and boundary conditions which require the numerical schemes to be implemented. Many distinct sketches are given to demonstrate the exactness of the numerical solutions measured.
The assembly of long reads from Pacific Biosciences and Oxford Nanopore Technologies typically requires resource-intensive error-correction and consensus-generation steps to obtain high-quality ...assemblies. We show that the error-correction step can be omitted and that high-quality consensus sequences can be generated efficiently with a SIMD-accelerated, partial-order alignment-based, stand-alone consensus module called Racon. Based on tests with PacBio and Oxford Nanopore data sets, we show that Racon coupled with miniasm enables consensus genomes with similar or better quality than state-of-the-art methods while being an order of magnitude faster.
•Methods of meso scale modelling are discussed with challenges and possible remedies.•Continuum analysis methods and discrete analysis methods are discussed.•Geometry generation, placing algorithms ...and material constitutive laws are discussed.•Applications of mesoscale modelling in fracture and durability are investigated.
Concrete can be considered as a heterogeneous material at mesoscale comprising of several constituents such as aggregates, mortar and Interfacial Transition Zone (ITZ). Mechanical behavior as well as the durability characteristics of concrete is highly dependent on the mesostructure of concrete and investigating the complex phenomena surrounding concrete at mesoscale considering the heterogeneity presents an important tool to understand these complex mechanisms. Presenting the state-of-the-art developments in mesoscale modelling of concrete considering different analysis methods such as continuum Finite Element Modelling (FEM), Lattice Element Method (LEM), Rigid Body Spring Method (RBSM), Discrete Element Method (DEM) and Lattice Discrete Particle Method (LDPM) is the focus of this review paper. Effective methods to generate the geometry of consisting phases in the mesoscale models including different particle shapes and placing algorithms, selecting suitable material constitutive relations for the consisting phases are discussed for these different methods of mesoscale modelling. Potential applications including fracture mechanics and strengths and weaknesses of each technique are highlighted with possible methods to overcome the challenges of mesoscale modelling of concrete.
The National Institutes of Health (NIH) funds training programs to increase the numbers and skills of scientists who obtain NIH research grants, but few programs have been rigorously evaluated. The ...sizeable recent NIH investment in developing programs to increase the diversity of the NIH-funded workforce, implemented through the Diversity Program Consortium (DPC), is unusual in that it also funds a Consortium-wide evaluation plan, which spans the activities of the 10 BUilding Infrastructure Leading to Diversity (BUILD) awardees and the National Research Mentoring Network (NRMN). The purpose of this article is to describe the evaluation design and innovations of the BUILD Program on students, faculty, and institutions of the 10 primarily undergraduate BUILD sites.
Our approach to this multi-methods quasi-experimental longitudinal evaluation emphasizes stakeholder participation and collaboration. The evaluation plan specifies the major evaluation questions and key short- to long-term outcome measures (or Hallmarks of Success). The Coordination and Evaluation Center (CEC) embarked on a comprehensive evaluation strategy by developing a set of logic models that incorporate the Hallmarks of Success and other outcomes that were collaboratively identified by the DPC. Data were collected from each BUILD site through national surveys from the Higher Education Research Institute at UCLA (HERI), annual followup surveys that align with the HERI instruments, site visits and case studies, program encounter data ("tracker" data), and institutional data. The analytic approach involves comparing changes in Hallmarks (key outcomes) within institutions for biomedical students who participated versus those who did not participate in the BUILD program at each institution, as well as between institution patterns of biomedical students at the BUILD sites, and matched institutions that were not BUILD grantees. Case studies provide insights into the institutionalization of these new programs and help to explain the processes that lead to the observed outcomes.
Ultimately, the results of the consortium-wide evaluation will be used to inform national policy in higher education and will provide relevant examples of institutional and educational programmatic changes required to diversify the biomedical workforce in the USA.
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