Inclusion Of Additional Parameters Research Articles

Chaos in gene regulatory networks: Effects of time delays and interaction structure.

In biological system models, gene expression levels are typically described by regulatory feedback mechanisms. Many studies of gene network models focus on dynamical interactions between components, but often overlook time delays. Here we present an extended model for gene regulatory networks with time delayed negative feedback, which is described by delay differential equations. We analyze nonlinear properties of the model in terms of chaos and compare the conditions with the benchmark homogeneous gene regulatory network model. Chaotic dynamics depend strongly on the inclusion of time delays, but the minimum motifs that show chaos differ when both original and extended models are considered. Our results suggest that, for a particular higher order extension of the gene network, it is possible to observe chaotic dynamics in a two-gene system without adding any self-inhibition. This finding can be explained as a result of modification of the original benchmark model induced by previously unmodeled dynamics. We argue that the inclusion of additional parameters in regulatory gene circuit models substantially enhances the likelihood of observing non-periodic dynamics.

Aspects of transthoracic echocardiography protocol in obese patients

Often, transthoracic echocardiography in obese patients reveals normal indicators of intracardiac hemodynamics and heart geometry. Can the clinician determine the risk of cardiovascular events and proper management in such patients based on the data obtained? Do many overweight patients really have no cardiac abnormalities, or they simply could not be detected? New capabilities of transthoracic echocardiography make it possible to detect abnormalities in the early stages of the disease, even in the absence of clinical manifestations. Thus, the inclusion of additional parameters in the standard protocol of echocardiography in obese patients will most accurately determine the management tactics and prognosis, thereby reducing the risk of unfavorable outcomes.

Global Moho Gravity Inversion from GOCE Data: Updates and Convergence Assessment of the GEMMA Model Algorithm

Since its discovery in 1909, the Moho was routinely studied by seismological methods. However, from the 1950s, a possible alternative was introduced by gravimetric inversion. Thanks to satellite gravity missions launched from the beginning of the 21st century, a global inversion became feasible, e.g., leading to the computation of the GEMMA model in 2012. This model was computed inverting the GOCE second radial derivatives of the anomalous potential by a Wiener filter, which was applied in the spherical harmonic domain, considering a two-layer model with lateral and vertical density variations. Moreover, seismic information was introduced in the inversion to deal with the joint estimation/correction of both density and geometry of the crustal model. This study aims at revising the GEMMA algorithm from the theoretical point of view, introducing a cleaner formalization and studying the used approximations more thoroughly. The updates are on: (1) the management of the approximations due to the forward operator linearization required for the inversion; (2) the regularization of spherical harmonic coefficients in the inversion by proper modelling the Moho signal and the gravity error covariances; (3) the inclusion of additional parameters and their regularization in the Least Squares adjustment to correct the density model by exploiting seismic information. Thanks to these updates, a significant improvement from the computational point of view is achieved too, thus the convergence of the iterative solution and the differences with respect to the previous algorithm can be assessed by closed-loop tests, showing the algorithm performance in retrieving the simulated “true” Moho.

Distinguishing and overlapping laboratory results of thrombotic microangiopathies in HIV infection: Can scoring systems assist?

Patients with Human Immunodeficiency Virus (HIV) infection are at risk of thrombotic microangiopathies (TMAs) notably thrombotic thrombocytopenic purpura (TTP) and disseminated intravascular coagulation (DIC). Overlap between laboratory results exists resulting in diagnostic ambiguity. Routine laboratory results of 71 patients with HIV-associated TTP (HIV-TTP) and 81 with DIC with concomitant HIV infection (HIV-DIC) admitted between 2015 and 2021 to academic hospitals in Johannesburg, South Africa were retrospectively reviewed. Both the PLASMIC and the International Society of Thrombosis and Haemostasis (ISTH) DIC scores were calculated. Patients with HIV-TTP had significantly (P < .001) increased schistocytes and features of hemolysis including elevated lactate dehydrogenase (LDH)/upper-limit-of-normal ratio (median of 9 (interquartile range [IQR] 5-12) vs 3 (IQR 2-5)) but unexpectedly lower fibrinogen (median 2.8 (IQR 2.2-3.4) vs 4g/L (IQR 2.5-9.2)) and higher D-dimer (median 4.8 (IQR 2.4-8.1) vs 3.6g/L (IQR 1.7-6.2)) levels vs the HIV-DIC cohort. Patients with HIV-DIC were more immunocompromised with frequent secondary infections, higher platelet and hemoglobin levels, more deranged coagulation parameters and less hemolysis. Overlap in scoring systems was however observed. The laboratory parameter overlap between HIV-DIC and HIV-TTP might reflect a shared pathogenesis including endothelial dysfunction and inflammation and further research is required. Fibrinogen in DIC may be elevated as an acute phase reactant and D-dimers may reflect the extensive hemostatic activation in HIV-TTP. Inclusion of additional parameters in TMA scoring systems such the LDH/upper-limit-of-normal ratio, schistocytes count and wider access to ADAMTS-13 testing may enhance diagnostic accuracy and ensure appropriate utilization of plasma.

Staphylococcus aureus-An Additional Parameter of Bathing Water Quality for Crowded Urban Beaches.

During the last years, the report of the occurrence of waterborne disease symptoms related to non-enteric pathogens has increased, without any record of higher levels of indicator bacteria (Escherichia coli and intestinal enterococci). Therefore, the use of current indicators is not always adequate when assessing the overall potential health risk and the inclusion of additional parameters needs to be examined. This paper reports on the incidence and levels of Staphylococcus aureus at 258 locations in Primorje-Gorski Kotar County (Croatia) recorded by official bathing water quality monitoring, as well as supplemental monitoring carried out at the two most frequented beaches in the City of Rijeka. The number of bathers was found to be the main factor affecting S. aureus levels (r = 0.321, p < 0.05). The share of S. aureus positive samples from the official monitoring was significantly lower, when compared to the share of samples from supplemental monitoring (2.2% and 36.3%, respectively; p < 0.01). Besides the number of bathers, one of the main reasons is likely the higher sampling frequency. No correlation was found between S. aureus levels and the indicator bacteria. The results indicate that the determination of S. aureus and increased sampling frequency is recommended for overcrowded beaches.

Correlation of Income Inequality and Entrepreneurial Activity

The fact of growth of inequality in distribution of income both inside the national economies and between the countries is confirmed by many empirical studies. In particular, these are annual reports of the World Bank, UNIDO and European Commission. The growth of inequality in distribution of income causes social tension inside the countries and promotes conflicts between the countries. Entrepreneurship serves as a form of softening social tension. Entrepreneurial activity ensures a significant percentage of employment and self-employment in many countries providing the income of the population at the level above the minimum consumption rate. In some cases, entrepreneurship could serve as a social lift for transition to a higher level of income distribution. The goal of this article is a statistical check of dependence between the level of income inequality and entrepreneurial activity in countries with different levels of GDP. A system approach and correlation analysis are used as the study methods. The statistical check of a correlation between the Gini index and level of entrepreneurial activity showed significant differences in the correlation degree of the said indicators for different countries and time periods. An assumption was made that there is a statistical dependence between the indicators, however, inclusion of additional parameters, among which we can find inequality of the property distribution and the level of institutional support of entrepreneurship, is required.

К ПРОБЛЕМЕ ОЦЕНКИ ТРАНСПОРТА НАНОСОВ

The paper discusses the problem of high errors in the design ratios proposed for assessing sediment transport in natural watercourses. The question is why numerous empirical design ratios obtained and successfully used for some watercourses can give an error of 1000% when applied to other rivers. Calculation formulas worked out on hydraulic trays and channels are found to be inappropriate for specific rivers and natural channels. The problem is caused by the complexity of the natural watercourses geometry and the heterogeneity of the bottom sediment composition. Two approaches that are currently used in assessing the transporting capacity of river flows are studied in the paper. They were laid down in river hydraulics as early as the second half of the 18th century in the works by A. Chesi and P. Dubois. The conditions and possibilities of using both methods are considered and theoretically proven in the paper. The approach developed by P. Dubois is distinguished by a detailed study of the influence of individual factors based on numerous experimental models, the construction of fairly rigorous physical models on this basis, the complication of design ratios, the inclusion of new additional parameters. A. Chesi offered the construction of a maximally simplified initial physical model, with the calibration parameters established for specific conditions on the basis of field observations or qualitative estimates, and therefore being less accurate but more stable. It is shown that despite the scientific attractiveness of the approach to constructing and using more complex calculation models containing new additional parameters, the inclusion of additional parameters entails the inclusion of additional errors associated with the estimation of these parameters. The effectiveness of both approaches is proved; the application of one or the other approach is determined by the conditions and nature of the tasks to be solved, as well as the volume and accuracy of the initial data.

Predicting laryngeal exposure in microlaryngoscopy: External validation of the laryngoscore.

Optimal laryngeal exposure during transoral laryngeal surgery is fundamental. We aimed to evaluate the reliability of a recently proposed score (Laryngoscore) in predicting difficult laryngeal exposure (DLE) in an independent cohort of patients undergoing elective microlaryngoscopy. We also verified the relation between DLE, surgeon's expertise, and difficult intubation, and investigated possible areas for score improvement. Prospective validation study. A total of 136 patients were preoperatively evaluated using the Laryngoscore. Patients were divided into three classes according to patient position, type of laryngoscope, and need for external counterpressure to expose the anterior commissure. Based on their mean scores, two groups were identified: good laryngeal exposure (GLE) and DLE. A receiver operating characteristic curve with the Youden index was used to calculate the optimal cutoff value. The χ2 and Fisher exact test were used to correlate GLE and DLE to the surgeon's expertise and difficult intubation. The intraoperative anatomical parameters underlying DLE were also recorded. The optimal cutoff value for differentiating GLE and DLE was 4, which identified 80.6% of DLE cases. No statistically significant difference in GLE and DLE distribution was found between surgeons (P = 0.43). The correlation between difficult intubation and DLE was statistically significant (P = 0.03). The intraoperative parameters determining DLE were epiglottis characteristics (floppy, tight, or short), bulky abdomen and chest, bulky tongue base, mobile teeth, and a narrow laryngeal aditus. The Laryngoscore is reliable for detecting DLE preoperatively. The inclusion of additional parameters may allow a more complete assessment and maximize its diagnostic accuracy. 2b Laryngoscope, 129:1438-1443, 2019.

Modes of Governance and Local Economic Development: An Integrated Framework for Comparative Analysis of the Globalizing Cities of India

This article explores how variations in provincial-state and city-level political cultures influence urban economic trajectory by mediating forces emerging out of global economic demand and a uniform national regulatory regime. The research shows how an integrated urban governance framework designed to analyze and compare governance modes of advanced capitalist cities through a fixed set of criteria (e.g., governing relations, governing logic, key decision makers, and political objectives) could be recalibrated through inclusion of additional parameters (e.g., local political culture and scalar location of power) so as to expand its applicability to an emerging economy, such as India, having a large, mostly poor, rural population and a high degree of internal sociocultural diversity. Competition between India’s regional elites to attract global information technology (IT)-enabled “business process outsourcing” economy investments, through land-use conversion of farmlands at the outer periphery of the metropolitan regions, forms the backdrop of the research.

Population structure and genetic variability in the Murrah dairy breed of water buffalo in Brazil accessed via pedigree analysis

The objective of this study was to use pedigree analysis to evaluate the population structure and genetic variability in the Murrah dairy breed of water buffalo (Bubalus bubalis) in Brazil. Pedigree analysis was performed on 5,061 animals born between 1972 and 2002. The effective number of founders (fe) was 60, representing 6.32 % of the potential number of founders. The effective number of ancestors (fa) was 36 and the genetic contribution of the 17 most influent ancestors explained 50 % of the genetic variability in the population. The ratio fe/fa (effective number of founders/effective number of ancestors), which expresses the effect of population bottlenecks, was 1.66. Completeness level for the whole pedigree was 76.8, 49.2, 27.7, and 12.8 % for, respectively, the first, second, third, and fourth known parental generations. The average inbreeding values for the whole analyzed pedigree and for inbreed animals were, respectively, 1.28 and 7.64 %. The average relatedness coefficient between individuals of the population was estimated to be 2.05 %-the highest individual coefficient was 10.31 %. The actual inbreeding and average relatedness coefficient are probably higher than estimated due to low levels of pedigree completeness. Moreover, the inbreeding coefficient increased with the addition of each generation to the pedigree, indicating that incomplete pedigrees tend to underestimate the level of inbreeding. Introduction of new sires with the lowest possible average relatedness coefficient and the use of appropriate mating strategies are recommended to keep inbreeding at acceptable levels and increase the genetic variability in this economically important species, which has relatively low numbers compared to other commercial cattle breeds. The inclusion of additional parameters, such as effective number of founders, effective number of ancestors, and fe/fa ratio, provides better resolution as compared to the inclusion of inbreeding coefficient and may help breeders and farmers adopt better precautionary measures against inbreeding depression and other deleterious genetic effects.

Decision trees as a simple-to-use and reliable tool to identify individuals with impaired glucose metabolism or type 2 diabetes mellitus

The prevalence of unknown impaired fasting glucose (IFG), impaired glucose tolerance (IGT), or type 2 diabetes mellitus (T2DM) is high. Numerous studies demonstrated that IFG, IGT, or T2DM are associated with increased cardiovascular risk, therefore an improved identification strategy would be desirable. The objective of this study was to create a simple and reliable tool to identify individuals with impaired glucose metabolism (IGM). A cohort of 1737 individuals (1055 controls, 682 with previously unknown IGM) was screened by 75 g oral glucose tolerance test (OGTT). Supervised machine learning was used to automatically generate decision trees to identify individuals with IGM. To evaluate the accuracy of identification, a tenfold cross-validation was performed. Resulting trees were subsequently re-evaluated in a second, independent cohort of 1998 individuals (1253 controls, 745 unknown IGM). A clinical decision tree included age and systolic blood pressure (sensitivity 89.3%, specificity 37.4%, and positive predictive value (PPV) 48.0%), while a tree based on clinical and laboratory data included fasting glucose and systolic blood pressure (sensitivity 89.7%, specificity 54.6%, and PPV 56.2%). The inclusion of additional parameters did not improve test quality. The external validation approach confirmed the presented decision trees. We proposed a simple tool to identify individuals with existing IGM. From a practical perspective, fasting blood glucose and blood pressure measurements should be regularly measured in all individuals presenting in outpatient clinics. An OGTT appears to be useful only if the subjects are older than 48 years or show abnormalities in fasting glucose or blood pressure.

Virulence of Classical Swine Fever virus isolates from Europe and other areas during 1996 until 2007

Classical Swine Fever (CSF) has caused several outbreaks in EU Member States with grave economic consequences. Several times the diagnosis of CSF was made too late partially due to non-specific clinical signs which did not raise suspicion for CSF. Virulence of CSF virus isolates (CSFV) still remains a subject of discussion and speculation as sufficient knowledge is still not available. Six uncharacterised CSFV isolates from 1996 to 2007 were assessed in animal experiments for their clinical virulence in order to broaden the knowledge about circulating CSFV and thereby assist disease eradication. A clinical (CS) and pathological score was applied and further extended by additional parameters to a modified CS (mCS) including case fatality, antibody production and leukocyte count. The unknown CSFV isolates could be classified as moderately or highly virulent. The inclusion of additional parameters, especially case fatality, into the mCS gave a more reliable classification of virulence, proving that there are clinical signs and laboratory parameters of blood which can be recognised. Therefore a subclinical course of infection is unlikely, especially in weaner pigs.

Retrospective analysis of relative parameter sensitivity in multi-generation reproductive toxicity studies

Current suggestions towards amending the OECD two-generation protocol include omission of the second generation and inclusion of additional parameters. This study analysed the relative parameter sensitivity in 18 individually published multi-generation studies with substances toxic to fertility. Among parameters that most often determined the reproductive LOAEL were weight of testis, dam and pup as well as litter size. Several other parameters were found to be unaffected in all studies evaluated. Some substances affected a specific set of parameters, indicating that rarely affected parameters may prove crucial in individual situations. This argues for the inclusion of a wide spectrum of parameters to cover all possible effects. Less sensitive parameters, mechanistically related to more sensitive ones, may be omitted as they will unlikely contribute to the overall LOAEL. This study gives first insights and needs follow-up by more extensive analyses before firm conclusions on the design of the two-generation study protocol can be drawn.

Updating linear models with dependent errors to include additional data and/or parameters

Although updating equations for general linear models exist, they have been restricted to formulations with uncorrelated error structure, or to models involving fixed parameters of fixed length with correlated error structure. In this paper updating equations are developed for general linear models with correlated errors when the parameter vector is supplemented or evolves as further data are added. These equations form part of a general review in which updating formulae for minimum variance, linear, unbiased parameter estimates and their variance, applicable where a general linear model is altered by the inclusion of additional parameters and/or data, and where the variance matrices for the model error and the parameter vector are known and nonsingular, are outlined. When variance matrices are estimated rather than known, the equations derived give estimated generalized least squares estimators. The formulae are developed for both fixed and random parameter vectors. For models in which additional data and parameters are added simultaneously, it is shown that a generalization of the Kalman filter is possible that allows for arbitrary forms of model error autocorrelation, given known nonsingular error variance.

Comparison of soil samples by high performance liquid chromatography augmented by absorbance ratioing

The study of the potential of soil comparisons by high performance liquid chromatography of organic extracts is continued with the inclusion of additional parameters viz. ratiograms and absorbance ratio values of prominent components. These additional markers allow for a more confident comparison without unduly complicating the analysis. On the basis of chromatographic profiles, ratiograms and absorbance ratio values of prominent peaks, soils are classified as chromatographically equivalent, quantitatively different or qualitatively different. The basis for this classification is discussed.

The influence of basin morphology on groundwater outflow

Twenty geomorphologic parameters which constitute a well‐balanced representation of the area, length, elevation, form, and shape aspects of watersheds as well as the texture of their drainage networks were considered. On the basis of groundwater theory and the results of previous related studies, eight of these parameters were identified as being relevant to the process of groundwater discharge. Values of the selected parameters were obtained for representative watersheds located in a section of the Appalachian Plateaus. The data, which were generated from U.S. Geological Survey topographic maps, were then subjected to a factor analysis to assess the relative importance of the parameters with respect to their influence on groundwater outflow behavior. The analytical results and their interpretation showed that among the parameters that are related to groundwater outflow, total length of perennial streams, average basin slope, and drainage density are the ones that are most closely related to the process. The influences of these parameters on groundwater outflow behavior are independent of each other. Thus in relating groundwater outflow characteristics to basin morphology, only these parameters need be considered and the inclusion of additional parameters does not necessarily yield a better relationship and may result in redundancy. The findings of the study are consistent with existing concepts regarding base flow (or drought flow) and have been confirmed by an independent study that investigated the process based on a more mechanistic approach.