Detection and Estimation of Genetic and Environmental Parameters through Model Fitting of Ten Bulb Yield Contributing Traits in Onion

Abstract This study presents a novel methodology for estimating the concentration of environmental pollutants in water, such as pathogens, based on environmental parameters. The scientific uniqueness of this study is the prevention of excess conformity in the model fitting by applying domain knowledge, which is the accumulated scientific knowledge regarding the correlations between response and explanatory variables. Sign constraints were used to express domain knowledge, and the effect of the sign constraints on the prediction performance using censored datasets was investigated. As a result, we confirmed that sign constraints made prediction more accurate compared to conventional sign-free approaches. The most remarkable technical contribution of this study is the finding that the sign constraints can be incorporated in the estimation of the correlation coefficient in Tobit analysis. We developed effective and numerically stable algorithms for fitting a model to datasets under the sign constraints. This novel algorithm is applicable to a wide variety of the prediction of pollutant contamination level, including the pathogen concentrations in water. This article has been made Open Access thanks to the generous support of a global network of libraries as part of the Knowledge Unlatched Select initiative.

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Estimation of parameters for a humidity-dependent compartmental model of the COVID-19 outbreak

PeerJ ◽

10.7717/peerj.10790 ◽

2021 ◽

Vol 9 ◽

pp. e10790

Author(s):

Csaba Farkas ◽

David Iclanzan ◽

Boróka Olteán-Péter ◽

Géza Vekov

Keyword(s):

Control Strategies ◽

Public Awareness ◽

Model Fitting ◽

Environmental Parameters ◽

Northern Region ◽

Contact Rate ◽

Estimation Of Parameters ◽

Time Dynamic ◽

A Value ◽

Novel Coronavirus

Building an effective and highly usable epidemiology model presents two main challenges: finding the appropriate, realistic enough model that takes into account complex biological, social and environmental parameters and efficiently estimating the parameter values with which the model can accurately match the available outbreak data, provide useful projections. The reproduction number of the novel coronavirus (SARS-CoV-2) has been found to vary over time, potentially being influenced by a multitude of factors such as varying control strategies, changes in public awareness and reaction or, as a recent study suggests, sensitivity to temperature or humidity changes. To take into consideration these constantly evolving factors, the paper introduces a time dynamic, humidity-dependent SEIR-type extended epidemiological model with range-defined parameters. Using primarily the historical data of the outbreak from Northern and Southern Italy and with the help of stochastic global optimization algorithms, we are able to determine a model parameter estimation that provides a high-quality fit to the data. The time-dependent contact rate showed a quick drop to a value slightly below 2. Applying the model for the COVID-19 outbreak in the northern region of Italy, we obtained parameters that suggest a slower shrinkage of the contact rate to a value slightly above 4. These findings indicate that model fitting and validation, even on a limited amount of available data, can provide useful insights and projections, uncover aspects that upon improvement might help mitigate the disease spreading.

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Detection and Estimation for Communication and Radar Systems

10.1017/cbo9781139015615 ◽

2009 ◽

Cited By ~ 11

Author(s):

Kung Yao ◽

Flavio Lorenzelli ◽

Chiao-En Chen

Keyword(s):

Detection And Estimation ◽

Radar Systems

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Three Conceptual Impediments to Developing Scale Theory for Formative Scales

Methodology ◽

10.1027/1614-2241/a000154 ◽

2018 ◽

Vol 14 (4) ◽

pp. 156-164 ◽

Cited By ~ 3

Author(s):

Keith A. Markus

Keyword(s):

Scale Development ◽

Item Analysis ◽

Model Fitting ◽

Item Bias ◽

Validity Evidence ◽

Scale Theory ◽

Underlying Theory ◽

Standard Scale ◽

Item Scores

Abstract. Bollen and colleagues have advocated the use of formative scales despite the fact that formative scales lack an adequate underlying theory to guide development or validation such as that which underlies reflective scales. Three conceptual impediments impede the development of such theory: the redefinition of measurement restricted to the context of model fitting, the inscrutable notion of conceptual unity, and a systematic conflation of item scores with attributes. Setting aside these impediments opens the door to progress in developing the needed theory to support formative scale use. A broader perspective facilitates consideration of standard scale development concerns as applied to formative scales including scale development, item analysis, reliability, and item bias. While formative scales require a different pattern of emphasis, all five of the traditional sources of validity evidence apply to formative scales. Responsible use of formative scales requires greater attention to developing the requisite underlying theory.

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Statistical Model Fitting: A State-of-the-Art Review

Contemporary Psychology ◽

10.1037/016731 ◽

1978 ◽

Vol 23 (11) ◽

pp. 937-938

Author(s):

JAMES R. KLUEGEL

Keyword(s):

Statistical Model ◽

State Of The Art ◽

Model Fitting

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An approach for comparative quantification of myocardial blood flow (0-15-H2O-PET), perfusion (Tc-99m-tetrofosmin-SPECT), and metabolism (F 18-FDG-PET)

Nuklearmedizin ◽

10.1055/s-0038-1623882 ◽

2001 ◽

Vol 40 (05) ◽

pp. 164-171 ◽

Cited By ~ 1

Author(s):

B. Nowak ◽

H.-J. Kaiser ◽

S. Block ◽

K.-C. Koch ◽

J. vom Dahl ◽

...

Keyword(s):

Blood Flow ◽

Myocardial Blood Flow ◽

Fdg Pet ◽

Model Fitting ◽

Compartment Model ◽

Left Ventricular ◽

Short Axis ◽

New Approach ◽

Single Compartment Model ◽

Tissue Fraction

Summary Aim: In the present study a new approach has been developed for comparative quantification of absolute myocardial blood flow (MBF), myocardial perfusion, and myocardial metabolism in short-axis slices. Methods: 42 patients with severe CAD, referred for myocardial viability diagnostics, were studied consecutively with 0-15-H2O PET (H2O-PET) (twice), Tc-99m-Tetrofosmin 5PECT (TT-SPECT) and F-18-FDG PET (FDG-PET). All dato sets were reconstructed using attenuation correction and reoriented into short axis slices. Each heart was divided into three representative slices (base, rnidventricular, apex) and 18 ROIs were defined on the FDG PET images and transferred to the corresponding H2O-PET and TT-SPECT slices. TT-SPECT and FDG-PET data were normalized to the ROI showing maximum perfusion. MBF was calculated for all left-ventricular ROIs using a single-compartment-model fitting the dynamic H2O-PET studies. Microsphere equivalent MBF (MBF_micr) was calculated by multiplying MBF and tissue-fraction, a parameter which was obtained by fitting the dynamic H2O-PET studies. To reduce influence of viability only well perfused areas (>70% TT-SPECT) were used for comparative quantification. Results: First and second mean global MBF values were 0.85 ml × min-1 × g-1 and 0.84 ml × min-1 × g1, respectively, with a repeatability coefficient of 0.30 ml ÷ min-1 × gl. After sectorization mean MBF_micr was between 0.58 ml × min1 ÷ ml"1 and 0.68 ml × min-1 × ml"1 in well perfused areas. Corresponding TT-SPECT values ranged from 83 % to 91 %, and FDG-PET values from 91 % to 103%. All procedures yielded higher values for the lateral than the septal regions. Conclusion: Comparative quantification of MBF, MBF_micr, TT-SPECT perfusion and FDG-PET metabolism can be done with the introduced method in short axis slices. The obtained values agree well with experimentally validated values of MBF and MBF_micr.

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HUBUNGAN KEPADATAN BIVALVIA DENGAN PARAMETER LINGKUNGAN DI PESISIR TANJUNG PURA KABUPATEN BANGKA TENGAH

Akuatik Jurnal Sumberdaya Perairan ◽

10.33019/akuatik.v13i2.1434 ◽

2020 ◽

Vol 13 (2) ◽

pp. 112-121

Author(s):

Sudiyar . ◽

Okto Supratman ◽

Indra Ambalika Syari

Keyword(s):

Negative Impact ◽

Principal Component ◽

Environmental Parameters ◽

Data Retrieval ◽

Distribution Patterns ◽

Random System ◽

System Method ◽

Relationship Of ◽

The Relationship ◽

Anadara Granosa

The destructive fishing feared will give a negative impact on the survival of this organism. This study aims to analyze the density of bivalves, distribution patterns, and to analyze the relationship of bivalves with environmental parameters in Tanjung Pura village. This research was conducted in March 2019. The systematic random system method was used for collecting data of bivalves. The collecting Data retrieval divided into five research stasions. The results obtained 6 types of bivalves from 3 families and the total is 115 individuals. The highest bivalve density is 4.56 ind / m², and the lowest bivalves are located at station 2,1.56 ind / m², The pattern of bivalve distribution in the Coastal of Tanjung Pura Village is grouping. The results of principal component analysis (PCA) showed that Anadara granosa species was positively correlated with TSS r = 0.890, Dosinia contusa, Anomalocardia squamosa, Mererix meretrix, Placamen isabellina, and Tellinella spengleri were positively correlated with currents r = 0.933.

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Recirculation versus flow-through rainbow trout laboratory Flavobacterium columnare challenge

Diseases of Aquatic Organisms ◽

10.3354/dao03487 ◽

2020 ◽

Vol 139 ◽

pp. 213-221

Author(s):

C Birkett ◽

R Lipscomb ◽

T Moreland ◽

T Leeds ◽

JP Evenhuis

Keyword(s):

Rainbow Trout ◽

Environmental Parameters ◽

Cumulative Effects ◽

Flavobacterium Columnare ◽

Replacement Rate ◽

Bacterial Concentration ◽

Water Replacement ◽

Dose Concentration ◽

Flow Through ◽

And Control

Flavobacterium columnare immersion challenges are affected by water-related environmental parameters and thus are difficult to reproduce. Whereas these challenges are typically conducted using flow-through systems, use of a recirculating challenge system to control environmental parameters may improve reproducibility. We compared mortality, bacterial concentration, and environmental parameters between flow-through and recirculating immersion challenge systems under laboratory conditions using 20 rainbow trout families. Despite identical dose concentration (1:75 dilution), duration of challenge, lot of fish, and temperature, average mortality in the recirculating system (42%) was lower (p < 0.01) compared to the flow-through system (77%), and there was low correlation (r = 0.24) of family mortality. Mean days to death (3.25 vs. 2.99 d) and aquaria-to-aquaria variation (9.6 vs. 10.4%) in the recirculating and flow-through systems, respectively, did not differ (p ≥ 0.30). Despite 10-fold lower water replacement rate in the recirculating (0.4 exchanges h-1) compared to flow-through system (4 exchanges h-1), differences in bacterial concentration between the 2 systems were modest (≤0.6 orders of magnitude) and inconsistent throughout the 21 d challenge. Compared to the flow-through system, dissolved oxygen during the 1 h exposure and pH were greater (p ≤ 0.02), and calcium and hardness were lower (p ≤ 0.03), in the recirculating system. Although this study was not designed to test effects of specific environmental parameters on mortality, it demonstrates that the cumulative effects of these parameters result in poor reproducibility. A recirculating immersion challenge model may be warranted to empirically identify and control environmental parameters affecting mortality and thus may serve as a more repeatable laboratory challenge model.

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