Distribution Of Values Research Articles

The impact of porous structure on oil–water two-phase flow under CO2 environment in continental shale reservoirs

CO2 applications for enhanced oil recovery and storage in continental shale reservoirs are promising, and there is a need to evaluate the impact of porous structure on oil–water two-phase flow under CO2 environment. In this study, first, digital cores of quartz-rich, carbonate-rich, and clay-rich shales are established using Focused Ion Beam Scanning Electron Microscopy scanning data processed through generative adversarial networks. Subsequently, the pore networks generated by digital cores are quantitatively analyzed using the generalized extreme value distribution. Finally, pore network modeling is carried out to elucidate the effect of porous structural differences on oil–water flow considering CO2 dissolution and capillary forces. The results show that quartz-rich shale, characterized by nanopore intergranular dominance and the highest pore network connectivity, demonstrates the highest relative permeability of the oil phase. Carbonate-rich shale exhibits intermediate relative permeability of oil phase, while clay-rich shale exhibits the worst. The dissolution of CO2 reduces oil–water interfacial tension and oil viscosity, enhances oil mobilization within nanopores, and notably increases the relative permeability of the oil phase. The permeability of the oil phase is governed by pore structure, displaying positive correlations with core heterogeneity, pore radius, coordination number, and throat length, and negative correlations with throat radius.

Establishing rainfall intensity-duration-frequency curves for Baghdad, Iraq using satellite data

Abstract Rainfall intensity-duration-frequency (IDF) curves were generated for Baghdad by utilising three satellite precipitation datasets: Global Satellite Mapping of Precipitation Near Real-Time (GSMaP NRT), gauge-corrected (GSMaP GC) and Global Precipitation Measurement Integrated Multi-Satellite Retrievals for Global Precipitation Measurement (IMERG). Maximum annual rainfall data was fitted using several probability distribution methods. The calculated coefficients from the best-fit distribution were used as fitting parameters to generate IDF curves for return periods of 2, 5, 10, 25, 50 and 100 years using the Sherman equation. To address discrepancies between the satellite-derived IDF curves and observed data, bias correction was performed based on the differences. The analysis revealed that the Generalized Extreme Value Distribution model accurately described the hourly rainfall distribution. GSMaP GC exhibited the highest correlation with the observed data, making it the preferred option for generating IDF curves. The study highlighted the importance of gauge correction for satellite rainfall data to minimise the underestimation or overestimation of rainfall. GSMaP GC demonstrated reasonable accuracy in estimating rainfall in Iraq’s mainly arid climate area. By assisting in the creation of efficient methods for dealing with rainstorm events, the created IDF curves are a major step towards advancing sustainable urban stormwater management in the country.

Value Distribution DDPG With Dual-Prioritized Experience Replay for Coordinated Control of Coal-Fired Power Generation Systems

Value Distribution DDPG With Dual-Prioritized Experience Replay for Coordinated Control of Coal-Fired Power Generation Systems

A chromosome-level genome assembly of Chinese quince (Pseudocydonia sinensis).

Pseudocydonia sinensis, also known as Chinese quince, is a perennial shrub or small tree highly valued for its edibility and medicinal properties. This study presents the first chromosome-level genome assembly of P. sinensis, achieved using HiFi sequencing and Hi-C scaffolding technology. The assembly resulted in a high-quality genome of 576.39 Mb in size. The genome was anchored to 17 pseudo-chromosomes, with a contig N50 of 27.6 Mb and a scaffold N50 of 33.8 Mb. Comprehensive assessment using BUSCO, CEGMA and BWA tools indicates the high completeness and accuracy of the genome assembly. Our analysis identified 116 species-specific genes, 1196 expanded genes and 1109 contracted genes. Additionally, the distribution of 4DTv values suggests that the most recent duplication event occurred before the divergence of P. sinensis from both Chaenomeles pinnatifida and Pyrus pyrifolia. The assembly of this high-quality genome provides a valuable platform for the genetic breeding and cultivation of P. sinensis, as well as for the comparison of the genetic complexity of P. sinensis with other important crops in the Rosaceae family.

Effect of the duration of vehicles’ idleness at transfer hubs of urban passenger transport on the conditions of synchronization of passenger transfers

Problem. The task of synchronizing the time of passengers' transfers between routes has been defined as one of the important directions for improving the operation of urban passenger transport in the transport and transfer hub. The simultaneous presence of route vehicles within the stops makes it possible to transfer passengers without waiting. Due to the action of external factors, compliance with the terms of coordination of the vehicles’ arrival at the transport hub is significantly complicated, which leads to a decrease in the efficiency of synchronization of passenger transfers and requires the implementation of additional management measures. Goal. The purpose of the work is to determine the effect of the duration of idleness of route vehicles in a transport interchange on the parameters of synchronization of passenger transfers and conflicting traffic within the stops. Methodology. The methodological basis for establishing the effect of the duration of vehicles’ idleness in a transport interchange on the efficiency of synchronization of passenger transfers is the developed structural model of the interaction of incoming route flows. Such a model describes the functional relationship between the traffic parameters of route vehicles, the distance between the initial stopping point of the route and the transfer point, the technical speed on network sections, the traffic intensity on routes, the idle time at intermediate stopping points, the average time of a passenger transfer and the number of conflict situations. Results. In the process of analyzing the object of the study, it was determined that it is possible to improve the conditions of synchronization of passenger transfers by increasing the duration of the stay of route vehicles at the stops. It was determined that the key role in synchronizing the transfer of passengers is played by the determination of the departure time of route vehicles from the initial stopping point, accounting for external impacts and laws of distribution of random values of the technical speed and the idle time at intermediate points. The developed circuit of functional communication allows to present the process of finding vehicles in a transport interchange as a complex system of synchronization of the route flows interaction. Originality. It is proposed to use a rational time of route vehicles idleness at the stop points of the transport and transfer hub, which allows to partially compensate for the decrease in the effectiveness of the synchronization of passenger transfers. When determining the time of vehicles idleness, the frequency of traffic conflicts that occur with adjacent routes at stopping points is also taken into account. The obtained regularities are presented in the form of characteristic functions, which allow to evaluate the effect of the duration of route vehicles stay in the transport interchange hub on the parameters of the efficiency of route flows interaction. Practical value. According to the results of experimental studies, the dependences of changes in the average passenger transfer time and conflicting traffic of route vehicles were established for the transport and transfer hub "Odeska St." (Kharkiv). It was determined that in the conditions of synchronization of the traffic schedule, the idle time of route vehicles within 180 seconds is rational. This enables to reduce the time of inter-route transfer of passengers and ensure a low level of conflict of the route vehicles traffic.

In Situ Sulfur Isotope Geochemistry Using Secondary Ion Mass Spectrometry of Sulfides in the ABM Replacement-Style Volcanogenic Massive Sulfide Deposit, Finlayson Lake District, Yukon, Canada

Abstract The ABM deposit is a bimodal-felsic, replacement-style volcanogenic massive sulfide deposit located in the Finlayson Lake district, Yukon, Canada, that is hosted by back-arc-affinity felsic volcanic rocks of the Yukon-Tanana terrane. Massive sulfide mineralization occurs as a series of stacked and stratabound lenses subparallel to the volcanic stratigraphy, surrounded by an envelope of pervasive white mica and chlorite alteration. Three major mineral assemblages occur: (1) a pyrite-sphalerite assemblage enriched in Zn-Pb-As-Sb-Ag-Au that formed at temperatures ∼200–270 °C, (2) a pyrite-chalcopyrite-magnetite-pyrrhotite assemblage enriched in Cu-Bi-Se-Co that formed at temperatures ∼300–350 °C, and (3) a chalcopyrite-pyrrhotite-pyrite stringer assemblage formed at temperatures >300 °C. In situ analysis of the sulfur isotopic ratios (δ34S) using secondary ion mass spectrometry has been performed on sulfides (pyrite, pyrrhotite, chalcopyrite, galena, and arsenopyrite) from samples representative of the major mineral assemblages. The δ34S results range between +4.0 and +12.5‰. The pyrite-sphalerite assemblage has an average δ34S value of +6.6 ± 1.8‰ (n = 31), whereas the higher temperature assemblages have an average δ34S value of +9.9 ± 1.4‰ (n = 59). Examination of the δ34S values of adjacent mineral pairs shows that the sulfides were formed under disequilibrium conditions and were not significantly altered or re-equilibrated by greenschist facies metamorphism that affected the ABM deposit post-volcanogenic massive sulfide formation. The observed range of δ34S values suggests that H2S derived from thermochemical sulfate reduction of seawater sulfate and/or an igneous sulfur source as the likeliest sources of S for the sulfides in the ABM deposit. Modeling of thermochemical sulfate reduction of contemporaneous Late Devonian seawater sulfate (δ34S ∼ +25‰) at temperatures estimated for the fluids forming the ABM deposit mineral assemblages (200–350 °C) shows that the reduction of 5–30% of the seawater sulfate would result in isotopic signatures similar to those observed at the ABM deposit. This model also explains the distribution of δ34S values across the mineral assemblages, as thermochemical sulfate reduction at higher temperatures (350 °C) results in more isotopically positive δ34S values. Modeling of mixing lines between thermochemical sulfate reduction at different temperatures and an igneous sulfur source suggests that leaching of magmatic/volcanic rocks also acted as a source of sulfur and was a likely a major contributor (70–95%) to the hydrothermal fluid system at the ABM deposit.

Comparative Analysis of the Reduced form Model and the Structural Model in Credit Risk Modelling

Credit risk models are statistical tools to infer the future default probabilities and loss distribution of values of a portfolio of debts. Credit risk modelling is prevalent in today’s financial decision-making process. It turns out that both models of modelling credit risk contribute to explaining the default risk of listed firms, however, reduce-form model outperformances the structural model. Structural models are used to calculate the probability of default for a firm based on the value of assets and liabilities. The basic idea is that a company (with limited liability) defaults if the value of its assets is less than the debt of the company. The causal driver of defaults in structural model will choose to work with variables that help us explain what causes defaults. Default risk is endogenous in the structural model, this is so because the factors that causes defaults within a path are predictable. The structural model is an economic model with focus on options pricing, call option and put option. It provides clarity about the nature of defaults and how the various economic features that are chosen to relate with each other when defaults occur. The reduced form model is mostly concerned with prediction of when does defaults occurs? Default risk is exogenous to the reduced form model, can be caused by random events and most often comes as a surprise. Statistical models are used to observe the variables and help maximise the reduced form model. The empirical result suggests that reduce-form model can better predict the firm’s default risk.

MODELLING STOCK PRICES OF A BANK WITH EXTREME VALUE DISTRIBUTIONS

The study investigates the application of Extreme Value Theory in modelling stock prices, aiming to capture the tail behaviour and extreme movements that conventional distributions often fail to represent accurately. The use of Extreme Value Theory has gained considerable attention in the field of finance due to its ability to model rare events, such as financial crises or market crashes. By incorporating Extreme Value Theory, researchers aim to improve risk management, portfolio optimization, and pricing of financial derivatives. In this study, the Log-normal, Weibull, Gamma, and Normal distributions were used to model the stock price closing data, with a specific focus on extreme value distributions. Both graphical explorations and goodness-of-fit criteria were considered together to evaluate the suitability of these distributions. When assessing the data, it was observed that the Weibull distribution provided the best fit for the given stock price closing data.

Simulated maximum likelihood estimation of the sequential search model

AbstractWe propose a new approach to simulate the likelihood of the sequential search model. By allowing search costs to be heterogeneous across consumers and products, we directly compute the joint probability of the search and purchase decisions when consumers are searching for the idiosyncratic preference shocks in their utility functions. Under the assumptions of Weitzman’s sequential search algorithm, the proposed procedure recursively makes random draws for each quantity that requires numerical integration while enforcing the conditions stipulated by the algorithm. In an extensive simulation study, we compare the proposed method with existing likelihood simulators that have recently been used to estimate the sequential search model. The proposed method attributes the uncertainty in the search order to the consumer-product-level distribution of search costs and the uncertainty in the purchase decision to the distribution of match values across consumers and products. This results in more precise estimation and an improvement in prediction accuracy. We also show that the proposed method allows for different assumptions on the search cost distribution and that it recovers consumers’ relative preferences even if the utility function and/or the search cost distribution is mis-specified. We then apply our approach to online search data from Expedia for field-data validation. From a substantive perspective, we find that search costs and “position” effects affect products in the lower part of the product listing page more than they do those in the upper part of the page.

Estimation of Marshall–Olkin Extended Generalized Extreme Value Distribution Parameters under Progressive Type-II Censoring by Using a Genetic Algorithm

In this article, we consider the statistical analysis of the parameter estimation of the Marshall–Olkin extended generalized extreme value under liner normalization distribution (MO-GEVL) within the context of progressively type-II censored data. The progressively type-II censored data are considered for three specific distribution patterns: fixed, discrete uniform, and binomial random removal. The challenge lies in the computation of maximum likelihood estimations (MLEs), as there is no straightforward analytical solution. The classical numerical methods are considered inadequate for solving the complex MLE equation system, leading to the necessity of employing artificial intelligence algorithms. This article utilizes the genetic algorithm (GA) to overcome this difficulty. This article considers parameter estimation through both maximum likelihood and Bayesian methods. For the MLE, the confidence intervals of the parameters are calculated using the Fisher information matrix. In the Bayesian estimation, the Lindley approximation is applied, considering LINEX loss functions and square error loss, suitable for both non-informative and informative contexts. The effectiveness and applicability of these proposed methods are demonstrated through numerical simulations and practical real-data examples.

On the distribution of zeros of analytic functions in angles in C\\{0}\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\mathbf{C} \\backslash \\{ {0}\\} $$\\end{document}

In this article some results on the value distribution theory of analyticfunctions defined in angles of C\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\mathbb{C}$$\\end{document}, due mainly to B. Ja. Levin and A. Pfluger,will be extended to the more general situation where the functions are defined inangles of C\\{0}\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\mathbb{C}\\backslash\\{ 0\\}$$\\end{document}. More precisely, angles S(θ1,θ2)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$S ( \ heta_{1},\ heta_{2}) $$\\end{document} with vertex at the origin will beconsidered and where a singularity at zero is allowed. An special class of thesefunctions are those of completely regular growth for which it is proved a basic resultwhich yields an expression of the density of its zeros in terms of the indicatorfunction.

Quantifying local cardiac substrate heterogeneity from high density recordings: an experimental study

Abstract Background and Purpose High-density (HD) grid catheters offer enhanced local electrical conduction characterization, owing to their unique grid arrangement. This arrangement enables the generation of orientation-independent EGMs, termed omnipolar EGMs (oEGMs), overcoming limitations associated with traditional unipolar and bipolar EGMs. This innovation holds potential for differentiating healthy tissue from scarred or arrhythmogenic areas. In this study, we introduce a novel metric, the Vector Field Heterogeneity (VFH), designed to quantify the heterogeneity of propagation wavefronts in local vector maps derived from oEGMs. Methods We developed and validated the VFH metric through a combination of simulations and experiment conducted on Langendorff-perfused rabbit hearts. Simulations involved creating a model that generated 100,000 simulated maps exhibiting various levels of disorganization. For experimental data, 68 propagation maps were utilized, including 29 from basal recordings, 39 from recordings with stimulation (4 or 6Hz), from five Langendorff-perfused rabbit hearts at 37ºC, using a multielectrode mapping catheter with 128 electrodes spaced 1mm apart. The VFH metric, based on vector field theory (see figure 2), was computed and compared to the widely adopted the Spatial Inhomogeneity Index (SI) from Statistical analysis was then performed to assess the distribution of heterogeneity values. Results The analysis of the VFH metric through simulations revealed a linear increase in VFH values with disorganization up to a 45º angle, followed by a plateau. Different catheter grid sizes demonstrated that larger grids reduced the standard deviation, with the VFH metric converging to a lower value of approximately 0.62 for larger grids. Experimental data indicated that for a 4x4 grid, VFH values averaged 0.35 without stimulation and decreased to 0.11 with stimulation. The VFH metric consistently outperformed the SI index in binary classification of basal vs stimulated conditions, as evidenced by higher Area Under Curve (AUC) values in both Receiver Operating Characteristic (ROC) and Precision-Recall (PR) analyses across various catheter sizes. For example, in the 4x4 grid, the AUROC for the VFH metric was 0.9752 compared to 0.8311 for the SI index, showcasing the VFH metric’s superior accuracy in assessing cardiac wavefront heterogeneity (see figure 2). Conclusion Vector Field Heterogeneity (VFH) emerges as an effective tool for characterizing cardiac tissue. It successfully differentiates between stimulated and non-stimulated tissue, accurately representing progressive disorganization in simulated maps. The VFH metric demonstrates superiority over the established Spatial Inhomogeneity (SI) index, making it a reliable parameter for assessing cardiac heterogeneity, especially on small high-density grids. It holds promise for clinical use in studying and understanding the cardiac substrate during arrhythmic conditions.Figure 1.Abstract Figure.Figure 2.Methods and Results.

Analysis of femur injury of vehicle frontal collision based on knee mapping test

In order to study the risk of dummy knee injuries in frontal collisions of automobiles, by analyzing a large number of knee mapping test data, the collision waveform intensity and the dummy knee risk situation were classified and counted. The influence laws of different characteristic risk points, collision speeds, and belt forces on femur loads were investigated. The results show that the distribution of OLC values at 50km/h is the largest in the range of 29-32g. The crash waveforms of both models are enhanced after speeding up, but the form of enhancement is different.The position where the driver is most likely to become a risk point is the steering column adjustment switch and the steering column cover bolts and brackets. The passenger seat is the transition area of the harder interior trim, and the highest risk point for femur loads exceeding the limit is the steering column adjustment switch. The highest median femur loads under different risk points is the hard corner of the central control screen. The femur loads increases with the increase of collision speed and decreases with the increase of seat belt tension.

Faraday rotation as a probe of radio galaxy environment in RMHD AGN jet simulations

Abstract Active galactic nuclei (AGN) play an integral role in galaxy formation and evolution by influencing galaxies and their environments through radio jet feedback. Historically, interpreting observations of radio galaxies and quantifying radio jet feedback has been challenging due to degeneracies between their physical parameters. In particular, it is well-established that different combinations of jet kinetic power and environment density can yield indistinguishable radio continuum properties, including apparent size and Stokes I luminosity. We present an approach to breaking this degeneracy by probing the line-of-sight environment with Faraday rotation. We study this effect in simulations of three-dimensional relativistic magnetohydrodynamic AGN jets in idealised environments with turbulent magnetic fields. We generate synthetic Stokes I emission and Faraday rotation measure (RM) maps, which enable us to distinguish between our simulated sources. We find enhanced RMs near the jet head and lobe edges. We show that increasing the environment density and the average cluster magnetic field strength broadens the distribution of Faraday rotation measure values. We study the depolarisation properties of our sources, finding that the hotspot regions depolarise at lower frequencies than the lobes. We quantify the effect of depolarisation on the RM distribution, finding that the frequency at which the source is too depolarised to measure the RM distribution accurately is a probe of environmental properties. This technique offers a range of new opportunities for upcoming surveys, including probing radio galaxy environments and determining more accurate estimates of the AGN feedback budget.

Linking School Culture to Successful Curriculum Reform

This study focused on the connection between organisational school culture and the success of curriculum reform. Utilizing a sample of 348 teachers in 25 Swiss schools, we investigated how different school culture types correlate with teachers’ perceived success of the current process of implementing the “Media and Information Literacy” curriculum. We found that the school culture type Clan is the most dominant across the schools and found a negative connection between the school culture type Hierarchy and teachers’ perceived reform success. An exploratory cluster analysis was used to identify further profiles of school culture that were not based on the dominant culture but were determined based on the distribution of mean values. Two other profiles were identified in a further procedure: Collegial Associates and Competitive Organisations. These results thus fill a gap in the previous research on school culture that had particularly set out to identify the dominant school culture. Based on the results, we cannot only confirm the validity of the Organisational Culture Assessment Instrument for Swiss schools but also give indications as to which characteristics of school culture types are hindering the perceived success of curriculum reforms from the teachers’ points of view.

The empire strikes back: the financialization of rental housing – a new frontier of accumulation and precarity

ABSTRACT The financialization of rental housing, driven by post-GFC financial contexts, sees assets concentrated in the hands of corporate landlords aided by technological innovations and state support. Foreclosures and evictions, especially in GFC-affected areas, enable corporate acquisition of property at bargain rates, followed by eviction strategies to increase turnover and rental prices, bypassing regulations. This upward distribution of value is supported by growing labor precarity, intertwined with rising rental prices globally. Labor market precarity, linked to stagnant wages, exacerbates housing precarity, creating new forms of accumulation by dispossession. The hypothesis suggests a convergence in “regulated deregulation,” blending formality and informality through financial processes, digital mechanisms, and public policies. Renting becomes a bridging mechanism, transforming housing into a service, managing time and income generation, with potential scalability through digital mechanisms. This marks a departure from historical constraints, potentially establishing unprecedented connections between informality and finance.

A conjecture of Zagier and the value distribution of quantum modular forms

In his influential paper on quantum modular forms, Zagier developed a conjectural framework describing the behavior of certain quantum knot invariants under the action of the modular group on their arguments. More precisely, when J_{K,0} denotes the colored Jones polynomial of a knot K , Zagier’s modularity conjecture describes the asymptotics of the quotient J_{K,0}(e^{2 \pi i \gamma(x)}) / J_{K,0}(e^{2 \pi i x}) as x \to \infty along rationals with bounded denominators, where \gamma \in \mathrm{SL}(2,\mathbb{Z}) . This problem is most accessible for the figure-eight knot 4_{1} , where the colored Jones polynomial has a simple explicit expression in terms of the q -Pochhammer symbol. Zagier also conjectured that the function h(x) = \log (J_{4_1,0}(e^{2 \pi i x}) / J_{4_1,0}(e^{2 \pi i /x})) can be extended to a function on \mathbb{R} which is continuous at irrationals. In the present paper, we prove Zagier’s continuity conjecture for all irrationals for which the sequence of partial quotients in the continued fraction expansion is unbounded. In particular, the continuity conjecture holds almost everywhere on the real line. We also establish a smooth approximation of h , uniform over all rationals, in accordance with the modularity conjecture. As an application, we find the limit distribution (after a suitable centering and rescaling) of \log J_{4_1,0}(e^{2 \pi i x}) , when x ranges over all reduced rationals in (0,1) with denominator at most N , as N \to \infty , thereby confirming a conjecture of Bettin and Drappeau.

Study on driving safety of vehicle-bridge interaction system based on ultra-high-dimensional point-selected extremum methods

ABSTRACT The driving safety indexes involve the geometric nonlinear contact relationship of the wheel and rail and the high-frequency vibration of the wheel-set. The calculation of their probability characteristic parameters requires very precise selection of random excitation samples. Track irregularity is an essential external excitation force in the vehicle-bridge interaction system (VBIS). Besides, many random phase angles must be considered when using the harmonic superposition method to simulate VBIS, leading to the ultra-high-dimensional random variables problem. Thus, this paper proposes a square power point method and a pseudo-random sequence (Sobol sequence) based on a number theoretic approach to model ultra-high dimensional random variables accurately. This strategy reduces the deviation between the representative track irregularity samples (TIS) and can be applied to fields of strongly nonlinear and high-frequency vibration. Then, by increasing the number of representative TIS, the deviation between response samples caused by non-linear factors can be significantly reduced. Finally, this paper proposes a threshold method for driving safety indexes that determines the service life of bridges, which can quickly obtain the threshold of its extreme value distribution through the cumulative distribution function, and establish the relationship between the threshold and the number of trains travelled. The above theories are verified by calculation examples, and some engineering suggestions are obtained.

Evaluation of diagnostic accuracy of urine neutrophil gelatinase-associated lipocalin in patients with symptoms of urinary tract infections: a meta-analysis.

Early and accurate diagnosis of urinary tract infection (UTI) can prevent serious sequelae including chronic kidney disease. Multiple individual studies have identified urine neutrophil gelatinase-associated lipocalin (uNGAL) as a promising biomarker for early diagnosis of UTI. We sought to understand the distribution and diagnostic accuracy of uNGAL values in patients presenting with UTI symptoms. Our systematic literature reviews in PubMed, Embase, and Cochrane Reviews up to March 2024, identified 25 studies reporting mean/median, standard deviation/quartiles, and detection limits of uNGAL in symptomatic patients with and without culture-confirmed UTI. Seventeen studies were in children. Meta-analyses were performed using the quantile estimation (QE) method estimating the distributions of uNGAL, which were then compared between the UTI and non-UTI groups for identifying the best cut-off points maximizing the Youden index. Sensitivity analyses were performed on all 25 studies including adult patients. We found that uNGAL levels were significantly higher in samples with confirmed UTI compared to those without. In pediatric studies, median and 95% confidence interval (CI) of uNGAL values were 22.41 (95% CI of 9.94, 50.54) ng/mL in non-UTI group vs. 118.85 (95% CI of 43.07, 327.97) ng/mL in UTI group. We estimated the cut-off point of 48.43 ng/mL with highest sensitivity (96%) and specificity (97%) in children. Sensitivity analysis including both pediatric and adult studies yielded similar results. The level of uNGAL in symptomatic patients with confirmed UTI is much higher than that reported in patients without UTI. It may be used as a diagnostic tool to identify UTI early among symptomatic patients. The range of uNGAL concentrations and cut-off points reported in subjects with UTI is much lower than that reported in patients with acute intrinsic kidney injury. https://www.crd.york.ac.uk/, PROSPERO (CRD42023370451).

Enhancing Visual Data Security: A Novel FSM-Based Image Encryption and Decryption Methodology

The paper presents a comprehensive exploration of a novel image encryption and decryption methodology, leveraging finite state machines (FSM) for the secure transformation of visual data. The study meticulously evaluates the effectiveness of the proposed encryption algorithm using a diverse image dataset. The encryption algorithm demonstrates high proficiency in obfuscating the original content of images, producing cipher images that resemble noise, thereby substantiating the encryption’s effectiveness. The robustness of the proposed methodology is further evidenced by its performance in the National Institute of Standards and Technology Statistical Test Suite (NIST STS). Such achievements highlight the algorithm’s capability to maintain the stochastic integrity of encrypted data, a critical aspect of data security and confidentiality. Histogram analysis revealed that the encryption process achieves a uniform distribution of pixel values across the encrypted images, masking any identifiable patterns and enhancing the security level. Correlation analysis corroborated the success of the encryption technique, showing a substantial reduction in the correlation among adjacent pixel values, thereby disrupting spatial relationships essential for deterring unauthorized data analysis. This improvement indicates the algorithm’s efficiency in altering pixel patterns to secure image data. Additionally, a comparative analysis of correlation coefficients using various encryption methods on the Lenna image offered insights into the relative effectiveness of different techniques, emphasizing the importance of method selection based on specific security requirements and data characteristics.