Miracle-dz/UniFAR-FTUs huggingface dataset:
Intraoperative Hypotension and Its Association with Postoperative Acute Kidney Injury in Patients Undergoing Pancreaticoduodenectomy: A 5-Year, Single-Center, Retrospective Cohort Study

Background Intraoperative hypotension (IOH) is a common phenomenon in high-risk surgery and is often linked to postoperative acute kidney injury (AKI). Pancreaticoduodenectomy (PD), or Whipple’s procedure, is a lengthy and complex surgical procedure to remove the head of the pancreas, gallbladder and bile duct, and the first part of the duodenum. This retrospective 5-year study from a single center in Poland included 303 patients who underwent PD and evaluated IOH as a factor associated with AKI. Material/Methods We analyzed perioperative data to assess how various IOH thresholds can predict AKI (according to KDIGO criteria). Several IOH definitions were applied, including absolute and relative thresholds, based on the mean arterial pressure (MAP). Statistically significant IOH thresholds were inserted into multivariable logistic regression models with previously established independent variables. Results We included 303 patients over a 5-year period (2016–2021). There were 58 (19.1%) cases of postoperative AKI. MAP <55 mmHg and a maximal% drop from preinduction MAP were the only IOH definitions associated with AKI. Multivariable analysis revealed that max% drop from preinduction MAP (per 10%, OR=1.65; AUROC=0.70) was the IOH definition best suited for AKI prediction in patients undergoing PD. Conclusions In patients undergoing PD, it is important to prevent excessive blood pressure drops in regards to preinduction blood pressure values. In this cohort, relative IOH thresholds were better suited for prediction of AKI than the absolute IOH thresholds.
On minimal rank over finite fields

Let F be a field. Given a simple graph G on n vertices, its minimal rank (with respect to F ) is the minimum rank of a symmetric n× nF -valued matrix whose off-diagonal zeroes are the same as in the adjacency matrix of G.I fF is finite, then for every k, it is shown that the set of graphs of minimal rank at most k is characterized by finitely many forbidden induced subgraphs, each on at most ( |F | k 2 +1 ) 2 vertices. These findings also hold in a more general context.
K.Čapek, Turing, von Neumann and the 20th Century Evolution ofthe Concept of Machine

During the 20 century, the concept of the machine in science and in society changed almost completely. This contribution sketches two ways – the way of literature (and theatre), and the way of science – of this change initiated by highly influential personalities of the 20 century – by the (play)writer Karel Capek, by mathematicians Alan M. Turing and John von Neumann, and by many others.
Capacitance study of inversion at the amorphous-crystalline interface of n-type silicon heterojunction solar cells

We use capacitance techniques to directly measure the Fermi level at the crystalline/amorphous interface in n-type silicon heterojunction solar cells. The hole density calculated from the Fermi level position and the inferred band-bending picture show strong inversion of (n)crystalline silicon at the interface at equilibrium. Bias dependent experiments show that the Fermi level is not pinned at the interface. Instead, it moves farther from and closer to the crystalline silicon valence band under a reverse and forward bias, respectively. Under a forward bias or illumination, the Fermi level at the interface moves closer to the crystalline silicon valence band thus increases the excess hole density and band bending at the interface. This band bending further removes majority electrons away from the interface leading to lower interface recombination and higher open-circuit voltage.
Existence of Equilibrium in Minimax Inequalities, Saddle Points, Fixed Points, and Games without Convexity Sets

This paper characterizes the existence of equilibria in minimax inequalities without assuming any form of quasi-concavity of functions and convexity or compactness of choice sets. A new condition, called “local dominatedness property”, is shown to be necessary and further, under some mild continuity condition, sufficient for the existence of equilibrium. We then apply the basic result obtained in the paper to generalize the existing theorems on the existence of saddle points, fixed points, and coincidence points without convexity or compactness assumptions. As an application, we also characterize the existence of pure strategy Nash equilibrium in games with discontinuous and nonquasiconcave payoff functions and nonconvex and/or noncompact strategy spaces.
On uniform fields in heterogeneous media

Uniform elastic strain fields are found in two-phase fibrous media of arbitrary transverse geometry, and in two-phase media of any phase geometry. In initially stress-free fibrous solids, a single uniform field can be created by certain proportionally changing tractions derived from a uniform overall stress. In the presence of phase eigenstrains, many overall stress states can be superimposed to create uniform strain fields in fibrous media. The existence of such fields is exploited to establish a number of exact results for two-phase fibre systems. These include universal connections between phase and overall moduli, and between components of phase stress and strain fields; expressions for new transformation influence functions and concentration factors in terms of their mechanical counterparts; and also expressions for the overall stresses and strains caused by phase eigenstrains. Examples are presented for macroscopically monoclinic fibrous composites with transversely isotropic phases. In two-phase media of arbitrary phase geometry there is only a single uniform stress and strain field for each non-vanishing eigenstrain state. The existence of this field is utilized in derivation of exact connections between transformation and mechanical influence functions and concentration factors.
Next Generation of Ovarian Cancer Detection Using Aptamers

Ovarian cancer is among the seven most common types of cancer in women, being the most fatal gynecological tumor, due to the difficulty of detection in early stages. Aptamers are important tools to improve tumor diagnosis through the recognition of specific molecules produced by tumors. Here, aptamers and their potential targets in ovarian cancer cells were analyzed by in silico approaches. Specific aptamers were selected by the Cell-SELEX method using Caov-3 and OvCar-3 cells. The five most frequent aptamers obtained from the last round of selection were computationally modeled. The potential targets for those aptamers in cells were proposed by analyzing proteomic data available for the Caov-3 and OvCar-3 cell lines. Overexpressed proteins for each cell were characterized as to their three-dimensional model, cell location, and electrostatic potential. As a result, four specific aptamers for ovarian tumors were selected: AptaC2, AptaC4, AptaO1, and AptaO2. Potential targets were identified for each aptamer through Molecular Docking, and the best complexes were AptaC2-FXYD3, AptaC4-ALPP, AptaO1-TSPAN15, and AptaO2-TSPAN15. In addition, AptaC2 and AptaO1 could detect different stages and subtypes of ovarian cancer tissue samples. The application of this technology makes it possible to propose new molecular biomarkers for the differential diagnosis of epithelial ovarian cancer.
Stability Analysis for Linear Systems with Time-Varying Delay

This paper studies the problem of stability analysis for continuous-time delay systems. By introducing a free weighting parameter, combining a novel Lyapunov functional with the switching system method, a new delay-dependent sufficient stability condition is obtained in terms of a linear matrix inequality (LMI). It is shown that this new criterion can provide less conservative results than all existing ones. Numerical examples are given to illustrate the effectiveness and advantages of the proposed method.
Spatiotemporal variability of minimum runoff generating areas: a field investigation

ABSTRACT Past studies described several dominant factors responsible for minimum runoff-generating areas (MRGAs) which are seldom backed by field observations. Here, soil moisture and runoff data for 45 rainfall events were collected from a small (21.62 ha) agricultural watershed in Ontario, Canada, using a remotely operated wireless sensor network system. The relationship developed between MRGA and basin moisture index (M) indicated that MRGAs are insensitive up to the threshold M value of 25 cm. A higher M leads to an exponential increase in the MRGA. Various factors (e.g. rainfall amount) affecting the spatiotemporal variability of MRGA were then identified. Statistical analyses (e.g. F-test) indicated a strong seasonal influence and showed that MRGA during spring, summer, and fall seasons was 34.3%, 8.0%, and 13.6%, respectively. The relationship of MRGA with rainfall amount, initial soil moisture content and rainfall intensity was the strongest for the summer season followed by fall and then spring.
Complete C4-C5 Dislocation Secondary to Shallow Water Diving in a Child: A Case-Based Update

Abstract Introduction Pediatric spinal cord injury (PSCI) is rare, especially secondary to shallow water diving, with only a few cases recorded in the literature. Due to the low standardization in the diagnosis and treatment of this condition, each of these cases requires a personalized approach. Case Description A 10-year-old female patient presented with tetraparesis and C5 sensory level secondary to spinal trauma due to shallow water diving. Computed tomography (CT) revealed complete C4-C5 dislocation, which led to a neurosurgical approach preceded by an intraoperative manual maneuver to reduce the dislocation. Following complete surgical reduction of the dislocation, the patient presented immediate significant neurological improvement. Conclusion Children need to be warned about diving, as SCI due to shallow water diving has a poor neurological outcome. Despite that, early diagnosis, stabilization, and surgical approach can lead to immediate significant neurological improvement. Considering the peculiarities of pediatric patients and the existence of varying care techniques in the literature, more studies comparing surgical and nonsurgical outcomes are fundamental.
A Comparison of Numerical Methods Applied to a Fractional Model of Damping Materials

The use of fractional derivatives in the constitutive equations of systems with damping materials provides a powerful tool for modeling these systems because the model does not exhibit many of the short comings of those based on integer-order derivatives. The resulting equations of motion possess closed-form solutions only for single-degree-of-freedom systems and only for a small number of loadings. For practical applications, therefore, the equations of motion must be solved using numerical methods. This paper presents two numerical schemes to solve single-degree- and multi-degree-of-freedom systems with fractional damp ing subjected to a number of commonly used loading conditions. The techniques employed are based on the central difference method and the average acceleration method. Whenever possible, the numerical results are compared with the analytical solutions. The results of the two numerical methods are essentially identical, with the exact solutions for zero initial conditions, but differ for nonzero conditions and large damping. For small damping, the average method has the advantage of its simpler formulation, especially with regard to the starting values. For arbitrary damping, however, the central difference method, in view of its robustness, is the preferred method.
Counting People Based on Multiple Targets Detection and Tracking

In this paper we proposed a method for determining the passenger flux based on SVM(support vector machine)detection and Mean Shift tracker.With adaptive detection window,the histogram of the gradient orientations is extracted through the detection region.After classification and clustering,the initial head hypotheses are obtained.Then,the Mean Shift tracker is used to track them,and image sequences of the head are achieved.By the whole decision on the consecutive head sequences using SVM,the number of people is obtained.Experimental results show that the adaptive sliding window method reduces the time consumption,and the accuracy of detection is improved by the combination with head tracking.
A Reinforcement Learning Based Coordinated but Differentiated Load Frequency Control Method With Heterogeneous Frequency Regulation Resources

As the diversification of frequency regulation resources, it is increasingly important to find a load frequency control (LFC) scheme that can effectively coordinate different resources. This paper proposes a coordinated but differentiated LFC control method that utilizes heterogeneous frequency regulation resources with their characteristics fully considered. The optimal LFC models for the single area and multi-area power systems are formulated as partially observable Markov decision process model (POMDP) and partially observable Markov game (POMG) considering the accessibility of system information. A deep reinforcement learning method called recurrent proximal policy optimization is leveraged to solve the POMDP and POMG models. Simulations based on historical data demonstrate that the proposed control scheme can better coordinate different resources and achieve superior control performance.
Application of artificial neural networks for gravity interpretation in two dimensions: a test study

In applied geophysics generalized bodies are often used to model the distribution of underground masses, such as spheres, vertical cylinders, vertical prisms, etc. Generally, discrimination between disturbing bodies producing similar kinds of anomalies is extremely difficult, or even impossible, with classical algorithms. In this paper we present a technique for gravity interpretation, based on the application of feed-forward, multi-layer artificial neural networks (ANNs), trained with back-propagation algorithms. This technique is used, firstly, to discriminate bodies producing a similar kind of anomaly. When the general shape of the body has been found (qualitative interpretation), the ANN method is applied to find the shape parameters like depth, vertical extension and radius. It is shown that after having been properly trained, an ANN is able to recognize a disturbing body with a degree of confidence higher than 99%. It is also shown that inversions carried out with this method produce quantitative results with accuracy ranging from 2% to 5%. The applications presented in this paper are based on synthetic data. These are the first steps towards a generalized technique of interpretation.
Valid inequalities, cutting planes and integrality of the knapsack polytope

Abstract In this paper we consider knapsack problem and knapsack polytope. Some important concepts and preliminaries are given at the beginning. Results connected with generation of valid and dominating inequalities (including the modular arithmetic approach), cutting planes, and integrality of the knapsack polytope are presented.
Theoretical study of the energetics, strain fields, and semicoherent interface structures in layer-by-layer semiconductor heteroepitaxy

A theoretical analysis based on continuum elasticity theory and atomistic simulations is presented of the interfacial stability with respect to misfit dislocation formation, the strain fields, and the film surface morphology during layer-by-layer semiconductor heteroepitaxy. The strain in the coherently strained films, the energetics of the transition from a coherent to a semicoherent interface consisting of misfit dislocation arrays or networks, the structure of the corresponding semicoherent interfaces, the strain fields associated with different equilibrium states of strain, and the morphological characteristics of the film surfaces are calculated for InAs/GaAs(110) and InAs/GaAs(111)A. The thickness of the epitaxial film is used as the dynamical variable in the analysis. Critical film thicknesses for transition from one equilibrium state of strain to another are computed. The analysis is presented for the more general case of heteroepitaxy on a finite-thickness compliant substrate, while the common ca.
Wine as a self-gift: a consumer approach

ABSTRACT Although the selection of wine as a gift has been discussed in the relevant literature, the purchase of wine as a self-gift remains unexplored. Driven by the assumption that a profound analysis of self-gifting patterns and behaviour could have some important marketing implications for the wine industry, the current paper attempts to identify the most common situational contexts for self-gifting wine and explore the consumer behaviour and decision-making process behind it. Using an exploratory approach, totally 32 in-depth interviews were conducted. Thematic analysis was used to analyse qualitative data. Results reveal that consumers being involved in negative emotional or stressful conditions are very likely to prefer wine as a self-gift. It is also common to purchase wine as a self-reward when celebrating an event. Based on the key findings of the study, wineries could adjust their marketing strategies by including the concept of self-gifting.
A fractional two‐step implicit algorithm using curvilinear collected grids

An efficient fractional two‐step implicit algorithm is reported to simulate incompressible fluid flows in a boundary‐fitted curvilinear collocated grid system. Using the finite volume method, the convection terms are discretized by the high‐accuracy Roe's scheme to minimize numerical diffusion. An implicitness coefficient Π is introduced to accelerate the rate of convergence. It is demonstrated that the proposed algorithm links the fractional step method to the pressure correction procedure, and the SIMPLEC method could be considered as a special case of the fractional two‐step implicit algorithm (when Π=1). The proposed algorithm is applicable to unsteady flows and steady flows. Three benchmark two‐dimensional laminar flows are tested to evaluate the performance of the proposed algorithm. Performance is measured by sensitivity analyses of the efficiency, accuracy, grid density, grid skewness and Reynolds number on the solutions. Results show that the model is efficient and robust. Copyright © 2006 John Wiley & Sons, Ltd.
Testing Linearity in Cointegrating Smooth Transition Regressions

This paper develops statistical tests that can be used to test linearity in cointegrating smooth transition regression models. These tests extend previous similar tests by considering I(1) regressors instead of stationary or mixing regressors and they also allow for more general transition mechanisms than in previous studies. As is typical in cointegrating regressions, the regressors and errors of the model can be serially and contemporaneously correlated. In order to allow for this feature, an endogeneity correction based on a leads-and-lags approach is employed. The proposed tests are very simple to use because ordinary least squares techniques and standard chi-square limiting distributions apply. Simulation experiments indicate that the tests have reasonable finite sample properties. Empirical applications to a U.K. money demand function illustrate the practical usefulness of the tests. Copyright Royal Economic Socciety 2004
Pattern recognition using 3-D moments

A 3-D moment method of object identification and positioning is proposed. Moments are computed from 3-D CAT image functions, 2.5-D range data, space curves, and discrete 3-D points. Objects are recognized by their shapes via moment invariants. Using an algebraic method, scalars and vectors are extracted from a compound of moments using Clebsch-Gordon expansion. The vectors are used to estimate position parameters of the object. Moment features of range data can be used in view-independent object recognition when the three-layer perceptron encodes the feature space distribution of the object in the weights of the network. Objects are recognized from an arbitrary viewpoint by the trained network. <<ETX>>
Cause and Counterfactual

It is shown how a causal ordering can be defined in a complete structure, and how it is equivalent to identifying the mechanisms of a system. Several techniques are shown that may be useful in actually accomplishing such identification. Finally, it is shown how this explication of causal ordering can be used to analyse causal counterfactual conditionals. First the counterfactual proposition at issue is articulated through the device of a belief-contravening supposition. Then the causal ordering is used to provide modal categories for the factual propositions, and the logical contradiction in the system is resolved by ordering the factual propositions according to these causal categories.
Evaluation Of Asian Option By Using RBFApproximation

This paper describes the evaluation of the price of the Asian option by using the radial bases function (RBF) approximation. In the previous study, we described the evaluation method of the European and the American options. In this paper, the Asian option is considered. A governing differential equation is discretized with the Crank-Nicholson scheme and the RBF approximation. The system of equations is solved for the option price. The numerical results are compared with the FDM solutions in order to confirm the validity of the formulation.
Analysis of a possible reason for oscillation phenomena in a diesel-generator set through catastrophe theory

In this paper, a possible reason for oscillation phenomena in a diesel-generator set is investigated through digital and analog network simulations. The nonlinear simulations of a swing equation show sudden deviations in the amplitude of rotor angle oscillations, provided that there exist periodic fluctuations of mechanical inputs to the generator unit. This kind of oscillation, different from the one that is identified in linear resonance, is thought to be caused by system nonlinearities and ill-combination of system parameters. The results of the analog simulations show the occurrence of bifurcation phenomenon in a electrical power mode. An approximate nonlinear model of the swing equation is found to hold the form of Duffing's equation. From the viewpoint of Duffing's equation, an instability assessment method is proposed using a catastrophe theory analogy.
Effects of Additives on Electrochromic Properties of Nanocrystalline Tungsten Oxide Films Prepared by Complexation-Assisted Sol–Gel Method

To improve the electrochromic (EC) properties of sol–gel-derived WO3 films, a series of organic small molecules, such as dopamine (DA), catechol, tyramine, phenol and 2-phenylethylamine, were added into peroxotungstic acid precursor sols as structure-directing additives, and five modified WO3 films were prepared by a simple and low-cost complexation-assisted sol–gel method. The effects of the above additives on the EC properties of the modified WO3 films have been studied in detail. Compared with the pure WO3 polycrystalline film, all the modified films combine the advantages of nanocrystalline and amorphous phases and show higher EC properties attributed to the unique nanocrystal-embedded amorphous structure. The results indicate that different additives with different numbers and types of functional groups (hydroxyl and amino groups) can change the microstructure, morphology, and thus electrochemical and EC properties of the films in various degrees. The additives, in order of their strong interactions with the sols, are DA, catechol, tyramine, phenol and 2-phenylethylamine, primarily depending on the number of hydroxyl groups. Of all the additives, DA with both catechol hydroxyl and amino groups shows the most positive effect; that is, the WO3 film modified with DA exhibits the best EC properties in terms of contrast, switching speed, stability, and coloration efficiency.