Discrete Field Research Articles

Natural language processing-optimized case selection for real-world evidence studies.

1556 Background: Much information describing a patient’s cancer treatment remains in unstructured text in electronic health records and is not recorded in discrete data fields. Accurate data completeness is essential for quality care improvement and research studies on de-identified patient records. Accessing this high-value content often requires manual and extensive curation review. Methods: AstraZeneca, CancerLinQ, ConcertAI, and Tempus have developed a natural language processing (NLP)-assisted process to improve clinical cohort selection for targeted curation efforts. Hybrid, machine-learning model development included text classification, named entity recognition, relation extraction and false positive removal. A subset of nearly 60,000 lung cancer cases were included from the CancerLinQ database, comprised of multiple source EHR systems. NLP models extracted EGFR status, stage, histology, radiation therapy, surgical resection and oral medications. Based on the results, cases were selected for additional manual curation, where curators confirmed findings of the NLP-processed data. Results: NLP methods improved cohort identification. Successfully returned cases using the NLP method ranged from 75.2% to 96.5% over more general case selection criteria based on limited structured data. For all cohorts combined, 84.2% of the cases sent out for NLP curation were returned with curated content (Table). Each cohort contained a range of NLP-derived elements for curators to further review. In comparison, more general case selection criteria yielded a total of 3,878 cases returned out of 41,186 lung cancer cases sent for curation, for a success rate of only 9.6%. Conclusions: NLP-driven case selection of six distinct, complex lung cohorts resulted in an order of magnitude improvement in eligibility over candidate selection using structured EHR data alone. This study demonstrates NLP-assisted approaches can significantly improve efficiency in curating unstructured health data. [Table: see text]

Kurihara Invariants and Elimination of Wild Ramification

The paper continues a series of papers devoted to study of the connection between two approaches to classification of complete discrete valuation fields with imperfect residue fields and, in particular, 2-dimensional local fields in the case of mixed characteristic. One of these approaches was introduced by Masato Kurihara (1987) in terms of the module of differentials. Another one is based on Epp’s theory of elimination of wild ramification. A lower bound for the degree of a constant field extension that makes a given field into an almost standard one is established. This bound is expressed in terms of the invariant introduced in Kurihara’s paper.

Modeling of affective-negative content in the course of schizophrenia

IntroductionThe world literature presents ambiguous results regarding the conjugation of negative and depressive syndromes, due to an incomplete understanding of the main symptoms of depression in schizophrenia.ObjectivesTo analyze the variants of the conjugation of depressive and negative symptoms at different stages of schizophrenia.MethodsWe used the data of our own observations (238 patients with a diagnosis of schizophrenia and no more than 5 years of experience of the disease) and compared them with the previously published results of studies. As a hypothesis, we analyze the variants of the conjugacy of affect and the negative domain within the framework of a single discrete field of schizophrenia.ResultsThe analysis shows that with the apparent heterogeneity of the psychopathological structure, some depressive features, such as apathy, anhedonia and social autism (characteristic of negative symptoms), tend to the abulia factor, whereas low mood, suicidal thoughts, pessimism, show affinity for the cluster of impoverishment of expression, that is, they represent an attenuated type of negative symptoms tending to the affective spectrum.ConclusionsThe conjugacy of depressive and negative disorders in schizophrenia, taking into account their phenomenological similarity, allows us to formulate a hypothesis about their existence within the framework of a single continuum model. The proposed continuum model can be used to understand the processes underlying pathogenesis and formulate the principles of personalized treatment and can be used as a starting point for research on the underlying biological processes and personalized treatment.DisclosureNo significant relationships.

Entanglement dynamics of thermofield double states in integrable models

We study the entanglement dynamics of thermofield double (TFD) states in integrable spin chains and quantum field theories. We show that, for a natural choice of the Hamiltonian eigenbasis, the TFD evolution may be interpreted as a quantum quench from an initial state which is low-entangled in the real-space representation and displays a simple quasiparticle structure. Based on a semiclassical picture analogous to the one developed for standard quantum quenches, we conjecture a formula for the entanglement dynamics, which is valid for both discrete and continuous integrable field theories, and expected to be exact in the scaling limit of large space and time scales. We test our conjecture in two prototypical examples of integrable spin chains, where numerical tests are possible. First, in the XY-model, we compare our predictions with exact results obtained by mapping the system to free fermions, finding excellent agreement. Second, we test our conjecture in the interacting XXZ Heisenberg model, against numerical iTEBD calculations. For the latter, we generally find good agreement, although, for some range of the system parameters and within the accessible simulation times, some small discrepancies are visible, which we attribute to finite-time effects.

Is there an infinite field whose multiplicative group is indecomposable?

In [2], we determined the finite fields with indecomposable multiplicative groups and conjectured that there is no infinite field whose multiplicative group is indecomposable. In this paper, we prove this conjecture for several popular classes of fields, including finitely generated fields, discrete valued fields, fields of Hahn series, local fields, global fields, and function fields.

Experimental Implementation of Energy Closure Analysis for Reduced Order Modeling

Abstract Reduced order models (ROMs) provide an efficient, kinematically condensed representation of computationally expensive high-dimensional dynamical systems; however, their accuracy depends crucially on the accurate estimation of their dimension. We here demonstrate how the energy closure criterion, developed in our prior work, can be experimentally implemented to accurately estimate the dimension of ROMs obtained using the proper orthogonal decomposition (POD). We examine the effect of using discrete data with and without measurement noise, as will typically be gathered in an experiment or numerical simulation, on estimating the degree of energy closure on a candidate reduced subspace. To this end, we used a periodically kicked Euler–Bernoulli beam with Rayleigh damping as the model system and studied ROMs obtained by applying POD to discrete displacement field data obtained from simulated numerical experiments. An improved method for quantifying the degree of energy closure is presented: the convergence of energy input to or dissipated from the system is obtained as a function of the subspace dimension, and the dimension capturing a predefined percentage of either energy is selected as the ROM dimension. This method was found to be more robust to data discretization error and measurement noise. The data-processing necessary for the experimental application of energy closure analysis is discussed in detail. We show how ROMs formulated from the simulated data using our approach accurately capture the dynamics of the beam for different sets of parameter values.

The structure and bearing capacity of rock structures during underground mining

The processes of controlling the ore-containing mass are refined and detailed, and the mechanism of interaction of stresses and deformations during underground mining of ore deposits is detailed. The properties of the massif and the role of faults and macrofractures in the development of deposits of complex structure are systematized. A methodology for studying stresses and deformations of rocks is given. Regularities of array maintenance at the interface site are established. Quantitative values of changes in physical and mechanical properties and stability of rocks in the interface zone are given. The array is differentiated by the magnitude of the acting stresses in various phases of the connection. The calculation of stresses for specific conditions with the determination of the reliability of the mining site was performed. Patterns of stress and strain changes over time are noted. An explanation of the phenomenon is given from the standpoint of the interaction of structural rock blocks in a discrete field of the array.

Harnessing the Data Universe to Understand and Reduce Clinical Deterioration in Children.

Harnessing the Data Universe to Understand and Reduce Clinical Deterioration in Children.

Robot Navigation Based on Potential Field and Gradient Obtained by Bilinear Interpolation and a Grid-Based Search.

The original concept of the artificial potential field in robot path planning has spawned a variety of extensions to address its main weakness, namely the formation of local minima in which the robot may be trapped. In this paper, a smooth navigation function combining the Dijkstra-based discrete static potential field evaluation with bilinear interpolation is proposed. The necessary modifications of the bilinear interpolation method are developed to make it applicable to the path-planning application. The effect is that the strategy makes it possible to solve the problem of the local minima, to generate smooth paths with moderate computational complexity, and at the same time, to largely preserve the product of the computationally intensive static plan. To cope with detected changes in the environment, a simple planning strategy is applied, bypassing the static plan with the solution of the A* algorithm to cope with dynamic discoveries. Results from several test environments are presented to illustrate the advantages of the developed navigation model.

Dynamic Bottleneck Identification of Manufacturing Resources in Complex Manufacturing System

Bottleneck identification is of great interest in discrete manufacturing fields, as they limit the system’s throughput. However, the bottlenecks are difficult to accurately identify due to the instability and complexity of discrete manufacturing systems. This paper proposes a dynamic bottleneck identification method (DBI-BS) that is based on effective buffers and fine-grained machine states to identify bottlenecks accurately. First, the complex manufacturing system (CMS) with strong coupling between elements is decoupled into several independent parts under the guidance of the effective buffer theory. Then, the machine activity duration method is improved through further fine-grained division, and the machine states are described by the timing flow model. The method to quantify the degree of bottleneck that restricts the system throughput (TH) is proposed on the basis of the turning point theory, and the one-to-one mapping relationship between the simulated and authentic complex manufacturing systems is also studied. Simulation results show that the DBI-BS can effectively identify dynamic bottlenecks in complex manufacturing processes, and the decoupling of complex systems can effectively improve the accuracy of dynamic bottleneck identification.

A Quality Initiative to Improve Postdischarge Care for Patients on Outpatient Parenteral Antimicrobial Therapy.

BackgroundPatients discharged from the hospital on outpatient parenteral antimicrobial therapy (OPAT) require close monitoring, including weekly blood tests and an early posthospital follow-up visit. However, because patients often receive OPAT in a separate healthcare system from where they received inpatient care, the OPAT plan often fails, with less than 75% of OPAT patients receiving the recommended laboratory monitoring. We sought to determine whether changing our inpatient OPAT documentation method would improve postdischarge care.MethodsAs a quality improvement initiative, we conducted 2 Plan-Do-Study-Act interventions on our OPAT documentation. Our first intervention was to create a standardized OPAT Progress Note, and our second was to turn that note into a SmartForm (Epic) with discrete fields for the key information. We examined the effects of these changes on the rate of completion of recommended laboratory monitoring, attendance at outpatient follow-up visits, and 30-day readmission rates.ResultsChanging our documentation to a standardized Progress Note and then to a SmartForm with discrete fields led to an increase in the proportion of patients with a serum creatinine checked within 10 days of discharge (from 63% to 71% to 73%) and who attended an infectious disease clinic visit within 3 weeks of discharge (from 21% to 36% to 47%). However, the rate of readmissions for OPAT-related problems did not change, nor did a composite outcome of 30-day mortality/unplanned readmission.ConclusionsChanges in how and where care plans are documented in the inpatient medical record can have significant effects on patient care outcomes after discharge.

A mass-conservative semi-implicit volume of fluid method for the Navier–Stokes equations with high order semi-Lagrangian advection scheme

This paper deals with the development of a semi-implicit numerical method for the Navier–Stokes equations using the non-linear volumes of fluid (VOF) approach and a semi-Lagrangian scheme for the discretization of the advection contribution based on a high order reconstruction of the velocity field. The VOF approach guarantees high flexibility and is able to reproduce several phenomena that appear in real scenarios such as free surface flows, pressurized channels and jets. The discrete velocity field from the momentum conservation law is formally inserted into the discrete continuity equation, hence yielding a mildly non-linear system for the unknown hydraulic head which can be solved through a nested Newton-type algorithm. The computation of the non-linear convective diffusion contribution is then based on a high order reconstruction of the velocity field, which is furthermore constrained to exactly recover the original pointwise values of the numerical solution. As a consequence, the mass conservation is fully preserved while providing information about the main velocity field and its high order moments, later employed in the computation of the Lagrangian trajectories needed for the discretization of the convective and diffusive terms. Furthermore, the bottom friction and the tangential stresses can be directly computed from the high order velocity reconstruction. The method is derived in a general form with the only requirement to be structured in the z− direction, so that it applies to the three- and the two-dimensional cases with unstructured grids in the horizontal space. Convergence studies are carried out to demonstrate the accuracy of the reconstruction operator. Finally, the numerical scheme is validated against several benchmarks that include 2Dxz, 2Dxy and 3D non-hydrostatic flows with complex geometry in order to show the flexibility of the proposed algorithm, including a real-world application.

Guideline Directed Medical Therapy In A Safety Net Hospital, Where Do We Stand?

<h3>Background</h3> : Despite a clear mandate to maximize guideline directed medical therapy (GDMT) for patients with heart failure with reduced ejection fraction (HFrEF), large registries have shown sub-optimal rates of both prescription and uptitration. Rates of GDMT in large community safety net hospitals are not well known. Moreover, the patient population of safety net hospitals is markedly different than contemporary registries. Our aim was to create an accessible, self-maintained, electronic health record (EHR) based registry of HFrEF patients that can be leveraged to describe rates of GDMT, and support quality improvement initiatives in a large safety net hospital. <h3>Methods</h3> : Left ventricular ejection fraction (LVEF) was recently made to be a mandatory field for all transthoracic echocardiograms, which is then pulled into the EHR as a discrete field. Using this data, we enrolled all patients with an LVEF ≤ 40% from August 2019-April 2021 at Parkland Health and Hospital System, a large 860 bed safety net hospital for Dallas, Texas (n=2,624). The registry was then queried for an ICD10 diagnosis of heart failure (n=2,555, 97.3%) and patients without an ICD10 diagnosis of heart failure (n=69) were adjudicated manually. Patients with a most recent LVEF ≤ 40% (n=2,447) were queried for heart failure pharmacotherapies and doses. <h3>Results</h3> : Our registry comprises a young, male predominant cohort that is racially and ethnically diverse as seen in table 1. In figure 1a we find prescription rates of GDMT on par with national cohorts with excellent prescription rates of ARNI and SGLT2 inhibitors, particularly in the 1,417 (57.9%) who have been seen in Cardiology or CHF clinics in the last 2 years. We found that the majority of patients on GDMT are on less than 50% of the goal dose as seen in figure 1b. <h3>Conclusion</h3> : The HFrEF population in a large safety-net hospital system was a young diverse population with rates of GDMT prescription similar to national cohorts, with higher rates of ARNI and SGLT2-inhibitors. The registry provides a platform for future quality improvement initiatives to increase GDMT prescription and uptitration.

A new numerical method for div-curl systems with low regularity assumptions

This paper presents a new numerical method for div-curl systems with the normal boundary condition by using a finite element technique known as primal-dual weak Galerkin (PDWG). The PDWG finite element scheme for the div-curl system has two prominent features in that it offers not only an accurate and reliable numerical solution to the div-curl system under the low Hα-regularity (α>0) assumption for the true solution, but also an effective approximation of the normal harmonic vector fields on domains with complex topology. Seven numerical experiments are conducted and the results are presented to demonstrate the performance of the PDWG algorithm, including one example on the computation of discrete normal harmonic vector fields.

Religija u diskursu savremenih znanstvenika – horizonti evolucionizma / Religion in the Discourse of Contemporary Scientists - The Horizons of Evolutionism

Religion has become a major extra-scientific interest of contemporary natural scientists. The topic permeates the discourse of some of the best known names in comtemporary science, including R. Dawkins, J. Lennox, F. Collins, and S. Gould. These scientists’ attitudes towards religion range from the view that science and religion are mutually exclusive and in conflict through the view that they are discrete fields without overlap to the view that they have to respect each other, engage in dialogue, and cooperate. One may discern in these approaches a number of discursive types: conflictual, integrative, dialogical, pluriperspectival, and discrete. These discourses unfold within the horizons of the epistemological constellations of evolutionism, creationism, intelligent design, and BioLogos. This paper has two main parts. The first part includes a treatment of key issues for understanding the relationship of science to religion: the question of evolutionism and, consequently, the theory of evolution, its scientific status, and its reception by theistic scientists; the attempt to establish a universal natural scientific epistemology and responses to it; and questions of the stochatic nature of the creation of the world and the origin of life. The second part includes consideration of the issue of theistic evolutionism and its major characteristics, followed by an exposition of the views of Christianity or more precisely of the Catholic Church regarding the theory of evolution and an investigation of certain echoes of its theistic reception.

Improving Data Collection and Abstraction to Assess Health Equity in Trauma Care.

Current trauma registries suffer from inconsistent collection of data needed to assess health equity. To identify barriers/facilitators to collecting accurate equity-related data elements, we assessed perspectives of national stakeholders, Emergency Department (ED) registration, and Trauma Registry staff. We conducted a Delphi process with experts in trauma care systems and key informant interviews and focus groups with ED patient registration and trauma registry staff at a regional Level I trauma center. Topics included data collection process, barriers/facilitators for equity-related data collection, electronic health record (EHR) entry, trauma registry abstraction, and strategies to overcome technology limitations. Responses were qualitatively analyzed and triangulated with observations of ED and trauma registry staff workflow. Expert-identified barriers to consistent data collection included lack of staff investment in changes and lack of national standardization of data elements; facilitators were simplicity, quality improvement checks, and stakeholder investment in modifying existing technology to collect equity elements. ED staff reported experiences with patients reacting suspiciously to queries regarding race and ethnicity. Cultural resonance training, a script to explain equity data collection, and allowing patients to self-report sensitive items using technology were identified as potential facilitators. Trauma registry staff reported lack of discrete fields, and a preference for auto-populated and designated EHR fields. Identified barriers and facilitators of collection and abstraction of equity-related data elements from multiple stakeholders provides a framework for improving data collection. Successful implementation will require standardized definitions, staff training, use of existing technology for patient self-report, and discrete fields for added elements.

Dynamic responses of the rail vehicle-bridge coupling system considering the spanwise correlation functions in vehicle aerodynamic forces

For rail vehicles, the spanwise correlation of aerodynamic forces acting on a single car is usually overlooked. To investigate the effects of spanwise correlation functions on the dynamic responses of the rail vehicle-bridge coupling system, firstly, the forms of spanwise correlation functions in the aerodynamic forces of a running vehicle, which are associated with the longitudinal and vertical fluctuating wind speeds, were proposed. Secondly, the spectra of buffeting forces acting on the running vehicle considering those spanwise correlation functions were obtained. Thirdly, a rail vehicle-bridge coupling system was established by using the commercial software SIMPACK, and a single car running on a typical high-speed railway bridge was taken as an example. Again, the effects of artificial discrete wind fields on the dynamic responses of the vehicle and bridge were investigated. Finally, the effects of the above spanwise correlation functions on the dynamic responses of the rail vehicle-bridge coupling system were compared under the cases of different vehicle speeds and wind speeds. The results show that different discrete time intervals can exert significant effects on the vehicle responses, and the discrete time interval of 0.05 s can be used for analysis in the wind-rail vehicle-bridge coupling system. With the increase of vehicle speed, the values of vehicle and bridge responses considering the spanwise correlation functions tend to be close to those without considering the spanwise correlation functions. However, as the wind speed increases, the values of vehicle and bridge responses generally tend to show greater differences in the presence and absence of spanwise correlation functions. At different vehicle speeds or wind speeds, the spanwise correlation functions have significant effects on the RMSs of vehicle accelerations and bridge lateral acceleration, but they have little effects on the bridge vertical acceleration.

Twisted Steinberg algebras

We introduce twisted Steinberg algebras over a commutative unital ring $R$. These generalise Steinberg algebras and are a purely algebraic analogue of Renault's twisted groupoid C*-algebras. In particular, for each ample Hausdorff groupoid $G$ and each locally constant $2$-cocycle $\sigma$ on $G$ taking values in the units $R^\times$, we study the algebra $A_R(G,\sigma)$ consisting of locally constant compactly supported $R$-valued functions on $G$, with convolution and involution "twisted" by $\sigma$. We also introduce a "discretised" analogue of a twist $\Sigma$ over a Hausdorff \'etale groupoid $G$, and we show that there is a one-to-one correspondence between locally constant $2$-cocycles on $G$ and discrete twists over $G$ admitting a continuous global section. Given a discrete twist $\Sigma$ arising from a locally constant $2$-cocycle $\sigma$ on an ample Hausdorff groupoid $G$, we construct an associated twisted Steinberg algebra $A_R(G;\Sigma)$, and we show that it coincides with $A_R(G,\sigma^{-1})$. Given any discrete field $\mathbb{F}_d$, we prove a graded uniqueness theorem for $A_{\mathbb{F}_d}(G,\sigma)$, and under the additional hypothesis that $G$ is effective, we prove a Cuntz--Krieger uniqueness theorem and show that simplicity of $A_{\mathbb{F}_d}(G,\sigma)$ is equivalent to minimality of $G$.

Signal processing of simplicial complexes

The paper considered the signal processing of simplicial complexes. Hodge decomposition formula for discrete fields is given, which is similar to the Hodge decomposition formula for smooth vector fields. The construction and the estimation of the gradient, divergence and curl operators and Laplace matrices for discrete vector fields are considered.

3D-print infill generation using the biological phase field of an optimized discrete material orientation vector field

A framework to produce an optimized infill structure for 3D-printed curvilinear fiber-reinforced polymer composites is proposed. The material orientation was optimized first to maximize the physical properties. Then, the phase field of the stripe pattern was developed based on the optimized material orientation vector field using the local activation and long-range inhibition system for the formation of biological patterns. Finally, the phase field was converted into a 3D print path. The proposed approach was validated both numerically and experimentally. The optimized infill structure showed a higher structural stiffness compared with commonly used infill structures prepared via concentric or rectilinear strategies, demonstrating the advantage of the proposed method.