Quantitative Comparison Research Articles

A-110 Analytical Performance Evaluation of Vitros® Immunodiagnostic Products Intact PTH II Assay

Abstract Background Intact parathyroid hormone (iPTH) is indicated to aid in the diagnosis of hyperparathyroidism, hypoparathyroidism, differential diagnosis of hypocalcemia or hypercalcemia and for intraoperative measurement of iPTH levels. Studies were conducted to evaluate the analytical performance of the Vitros Immunodiagnostic Products Intact PTH II (Vitros iPTH II) assay by determining limit of detection (LoD), limit of quantitation (LoQ), and precision. A method comparison of the Vitros iPTH II assay against the Roche Elecsys PTH assay was also conducted. Methods The LoD and LoQ were determined consistent with CLSI EP17. Precision was evaluated consistent with CLSI EP05 using six patient pools for 20 days. Repeatability was determined using two replicates per run. Within-lab precision was determined using a single reagent lot and a single calibration. A quantitative comparison between the Vitros iPTH II assay on a Vitros 3600 system and the Roche Elecsys PTH assay on a Roche Cobas 8000 system was conducted in accordance with CLSI guideline EP09 using 206 endogenous patient samples. Samples were selected to cover the full measuring interval and were tested over a total of six non-consecutive days. Results The LoD for the Vitros iPTH II assay was determined to be 1.7 pg/mL. The claimed LoQ was determined using a precision profile approach with a %CV limit of 20% and set at 1.7 pg/mL. For mean parathyroid hormone (PTH) concentrations ranging from 15.9 to 4656 pg/mL, repeatability (within-run) percent coefficient of variation (%CV) ranged from 0.8% to 1.4% and within-lab %CV ranged from 1.5% to 3.0%. The method comparison of the Vitros iPTH II assay versus the Roche Elecsys PTH assay yielded a correlation coefficient of 0.991 and a Passing-Bablok regression slope of 1.01 and intercept of 0.3. Conclusions The Vitros iPTH II assay demonstrated acceptable analytical performance in these studies, with high correlation and close agreement to the Roche Elecsys PTH assay.

A-033 Comparison of the Roche hCG STAT and hCG+β Assays

Abstract Background Roche Diagnostics offers hCG STAT and Elecsys hCG+β for the quantitative determination of human chorionic gonadotropin (hCG) in serum. While hCG STAT detects intact hCG after a 9-minute incubation, hCG +β; detects intact hCG, nicked hCG forms, the β-core fragment and the free β-subunit after 18 minutes. The manufacturer reported a strong correlation (R = 0.999) between the two assays using 81 samples with hCG concentrations ranging from 6 - 7675 mIU/mL. However, hCG concentrations during early pregnancy are low. This study aims to determine the correlation between the two assays with samples of < 50 mIU/mL hCG concentration. Additionally, we aim to determine the qualitative concordance between the two assays assuming the upper 95% confidence limit reported by the manufacturer as the positive cutoff value. Methods We compared hCG results from a cohort of remnant serum samples (N = 65; hCG 2 - 49 mIU/mL) previously analyzed using the Elecsys hCG + β assay on Roche cobas e 801 analyzers against the Elecsys HCG STAT assay on the cobas e 601 analyzers. A quantitative method comparison was also performed on a subset (N =33) of samples with hCG < 5 mIU/mL. Regression analysis was conducted using EP Evaluator software (version 12). A qualitative concordance between the two assays was performed assuming the upper 95% confidence limit in healthy, non-pregnant premenopausal women as the positive cutoff value (5.3 mIU/mL and 4.9 mIU/mL for the hCG+β and hCG STAT assay, respectively). Results Quantitative comparison using a wider range revealed an R value of 0.968, however, at hCG < 5mIU/ml concentration, the R value was 0.755. Qualitative comparison using each assay’s cutoff value identified seven discrepancies. Three samples that would be classified as positive with the hCG+β assay would be considered negative with hCG STAT assay, and four samples that would be considered negative with the hCG+β assay would be classified as positive with the hCG STAT assay. When a 4.9 mIU/mL cutoff value is used for both assays, eight samples that would be positive with the hCG+β assay would be considered negative with the hCG STAT assay, and one sample goes the other way. Conversely, if 5.3 mIU/mL is used as a cutoff value for both assays, three samples that would be classified as positive with the hCG+β assay would be considered negative with the hCG STAT assay, and one sample tested the other way. Conclusions The correlation between the two assays is strongest when comparison is made using a wide range of hCG values, consistent with the manufacturer's claims. However, the correlation weakens when comparing samples with low hCG values. Qualitative comparison of the assays using their respective cutoff values resulted in 89.2% overall agreement, 84.6% when a lower cutoff value of 4.9mIU/ml is used and 93.8% overall agreement when 5.3mIU/ml cutoff value used. We concluded that while the assays are comparable, minor differences were observed at low hCG values. Further study using a larger sample size and clinical correlation is needed to reinforce the conclusions.

A-009 Analytical Characterization of a Novel NT-proBNP Assay on a Central Laboratory Platform

Abstract Background N-terminal pro-B-type Natriuretic Peptide (NT-proBNP) or B-type Natriuretic Peptide (BNP) assay(s) are widely measured with a Class 1, Level of Evidence A recommendation in professional heart failure (HF) guidelines for diagnosis and prognosis. We present the analytical characteristics of the first NT-proBNP assay on Beckman Coulter platforms. Methods Measurements were conducted with the Access NT-proBNP assay, a one-step sandwich immunoenzymatic assay using monoclonal capture and detection antibodies, on the DxI 9000 Immunoassay Analyzer with Lithium Heparin (LiHep) plasma samples. Performance was characterized according to CLSI guidelines for: Limit of Blank (LoB), Limit of Detection (LoD), Limit of Quantitation (LoQ), linearity, imprecision (repeatability, reproducibility) and matrix comparison with LiHep, EDTA and serum. Reference intervals (RI) were evaluated in a healthy, adult U.S. population comprised of 675 subjects with 54.6% females, 79.1% White and 15.1% Black individuals. Exclusion criteria included elevated cardiac troponin, abnormal eGFR and cardiac medications. The 97.5th percentile RI upper limit was defined for age-stratified ranges of <50, 50-75, and >75 years old. Results Performance was LoB=1.1ng/L; LoD=4.8ng/L; LoQ=4.8ng/L; linearity=35,000ng/L. Repeatability ranged from 1.5%-3.5% and reproducibility from 2.3%-7.9% in seven samples ranging from 38ng/L to 23,848ng/L. Matrix measurement regression (n=68) yielded slopes of 1.00, 1.01; intercepts -0.03 to -2.63; r=0.98. Table 1 shows that NT-proBNP values increase with age and women generally have higher values than men. Conclusions The LoB, LoD and LoQ demonstrate highly sensitive low-end characteristics. Repeatability and reproducibility show excellent performance across a wide measurement range. NT-proBNP values are known to be age dependent, and the age-stratified 97.5th percentile RI upper limits were 162 ng/L for <50 years, 311 ng/L for 50-70 years, and 457 ng/L for >75 years. This novel Access NT-proBNP assay offers robust analytical performance as an aid to clinical HF management in acute settings.

Ionic selectivity of nanopores: Comparison among cases under the hydrostatic pressure, electric field, and concentration gradient

The ionic selectivity of nanopores is crucial for the energy conversion based on nanoporous membranes. It can be significantly affected by various parameters of nanopores and the applied fields driving ions through porous membranes. Here, with finite element simulations, the selective transport of ions through nanopores is systematically investigated under three common fields, i.e. the electric field (V), hydrostatic pressure (p), and concentration gradient (c). For negatively charged nanopores, through the quantitative comparison of the cation selectivity (t+) under the three fields, the cation selectivity of nanopores follows the order of t+V > t+c > t+p. This is due to the transport characteristics of cations and anions through the nanopores. Because of the strong transport of counterions in electric double layers under electric fields and concentration gradients, the nanopore exhibits a relatively higher selectivity to counterions. We also explored the modulation of t+ on the properties of nanopores and solutions. Under all three fields, t+ is directly proportional to the pore length and surface charge density, and inversely correlated to the pore diameter and salt concentration. Under both the electric field and hydrostatic pressure, t+ has almost no dependence on the applied field strength or ion species, which can affect t+ in the case of the concentration gradient. Our results provide detailed insights into the comparison and regulation of ionic selectivity of nanopores under three fields which can be useful for the design of high-performance devices for energy conversion based on nanoporous membranes.

4-plex quantitative glycoproteomics using glycan/protein-stable isotope labeling in cell culture

Alterations in glycoprotein abundance and glycan structures are closely linked to numerous diseases. The quantitative exploration of glycoproteomics is pivotal for biomarker discovery, but comprehensive analysis within biological samples remains challenging due to low abundance, complexity, and lack of universal technology. We developed a multiplex glycoproteomic approach using an LC-ESI-MS platform for direct comparison of glycoproteomic quantitation. Glycopeptides were isotopically labeled during cell culture, achieving high labeling efficiency (≥ 95 %) for both glycans and peptides. Quantitation was validated by mixing the same cell line in a 1:1:1:1 ratio, with mathematical correction applied to deconvolute the ratios. This method proved reliable and was applied to a comparative glycoproteomic study of three breast cancer cell lines (HTB22, MDA-MB-231, MDA-MB-231BR) and one brain cancer cell line (CRL-1620), quantifying glycopeptides from three replicates. The expression of glycopeptides was relatively quantified, and up/down-regulation between cell lines was investigated. This approach provided insights into glycosylation microheterogeneity, crucial for breast cancer brain metastasis research. Benefits include eliminating fluctuations from nano electrospray ionization and reducing analysis time, enabling up to 4-plex profiling in a single injection. Metabolic labeling introduced mass differences at the MS1 level, ensuring increased sensitivity and higher resolution for accurate quantitation. SignificanceAlternations in glycoprotein abundance, changes in glycosylation levels, and variations in glycan structures are closely linked to numerous diseases. The quantitative exploration of glycoproteomics has emerged as a popular area of research for biomarker discovery. However, conducting a comprehensive quantitative analysis of the glycoproteome within biological samples remains challenging due to low abundance, inherent complexities, and the absence of universal quantitative technology. Here, we developed a multiplex glycoproteomic approach using an LC-ESI-MS platform to facilitate direct comparison of glycoproteomic quantitation and enhance throughput. This approach offers benefits such as eliminating quantitative fluctuations arising from nano electrospray ionization (ESI) and reducing analysis time, enabling up to 4-plex glycoproteomic profiling in a single injection. Glycopeptides were stable isotopic labeled during cell culture procedure, attaching to monosaccharides, amino acids, or both. We achieved a high labeling efficiency (≥ 95 %) for both glycans and peptides. Quantitation validation was tested on glycopeptides by mixing the same cell line with 1:1:1:1 ratio. Due to the overlapped isotopes, a mathematical correction was applied to deconvolute the ratio of 4-plex glycopeptides. This method demonstrated quantitative reliability and was successfully applied to a comparative glycoproteomic study of three breast cancer cells (HTB22, MDA-MB-231, and MDA-MB-231BR) and one brain cancer cell (CRL-1620), identifying a total of 264 glycopeptides from three replicates. The expression of glycopeptides among these four cells was relatively quantified and up/down-regulation between two cell lines was investigated. The exploration of glycosylation microheterogeneity through glycopeptide quantification may offer valuable insights for further investigation into breast cancer brain metastasis.Conclusion: The primary advantage of our presented work lies in the multiplexing offered by combining two established labeling techniques, SILAC and IDAWG, both of which have been effectively used and widely cited in the scientific community. This combination enhances the applicability and accuracy of our method, as demonstrated by the extensive citations and successful use of these techniques independently. We believe that this multiplexing approach significantly advances the field, despite the method's current limitation to cell systems.

A Quantitative Comparison and Validation of Finite‐Fault Models: The 2011 Tohoku‐Oki Earthquake

AbstractLarge earthquakes rupture faults over hundreds of kilometers within minutes. Finite‐fault models image these processes and provide observational constraints for understanding earthquake physics. However, finite‐fault inversions are subject to non‐uniqueness and uncertainties. The diverse range of published models for the well‐recorded 2011 9.0 Tohoku‐Oki earthquake illustrates this challenge, and its rupture process remains under debate. Here, we comprehensively compare 32 published finite‐fault models of the Tohoku‐Oki earthquake. We aim to identify the most coherent slip features of the Tohoku‐Oki earthquake from these slip models and develop a new method for quantitatively analyzing their variations. We find that the models correlate poorly at 1‐km subfault size, irrespective of the data type. In contrast, model agreement improves significantly with increasing subfault sizes, consistently showing that the largest slip occurs up‐dip of the hypocenter near the trench. We use the set of models to test the sensitivity of available teleseismic, regional seismic, and geodetic observations. For the large Tohoku‐Oki earthquake, we find that the analyzed finite‐fault models are less sensitive to slip features smaller than 64 km. When we use the models to compute synthetic seafloor deformation, we observe strong variations in the synthetics, suggesting their sensitivity to small‐scale slip features. Our newly developed approach offers a quantitative framework to identify common features in distinct finite‐fault slip models and to analyze their robustness using regional and global geophysical observations for megathrust earthquakes. Our results indicate that dense offshore instrumentation is critical for resolving the rupture complexities of megathrust earthquakes.

Binocular Scheimpflug light-field PIV

This work presents theoretical and experimental studies on a binocular Scheimpflug light-field based PIV. To investigate the effects of key parameters such as magnification, camera separation angle and tilt angle, a simulation study and quantitative comparison between conventional and binocular Scheimpflug light-field PIV have been performed. To validate the performance of binocular Scheimpflug light-field PIV, a series of vortex ring experiments have been carried out with different parameters. A comparison of the reconstructed volume and quality of the resolved vortex ring structures shows the advantages of binocular Scheimpflug light-field PIV. With Scheimpflug imaging, the focal plane of two light-field cameras can be fully overlapped which results in an extended reconstructed particle volume and less distortion in the resolved flow field than conventional binocular light-field PIV.

Estimating pathogen spread using structured coalescent and birth–death models: A quantitative comparison

Elucidating disease spread between subpopulations is crucial in guiding effective disease control efforts. Genomic epidemiology and phylodynamics have emerged as key principles to estimate such spread from pathogen phylogenies derived from molecular data. Two well-established structured phylodynamic methodologies – based on the coalescent and the birth–death model – are frequently employed to estimate viral spread between populations. Nonetheless, these methodologies operate under distinct assumptions whose impact on the accuracy of migration rate inference is yet to be thoroughly investigated.In this manuscript, we present a simulation study, contrasting the inferential outcomes of the structured coalescent model with constant population size and the multitype birth–death model with a constant rate. We explore this comparison across a range of migration rates in endemic diseases and epidemic outbreaks. The results of the epidemic outbreak analysis revealed that the birth–death model exhibits a superior ability to retrieve accurate migration rates compared to the coalescent model, regardless of the actual migration rate. Thus, to estimate accurate migration rates, the population dynamics have to be accounted for. On the other hand, for the endemic disease scenario, our investigation demonstrates that both models produce comparable coverage and accuracy of the migration rates, with the coalescent model generating more precise estimates. Regardless of the specific scenario, both models similarly estimated the source location of the disease.This research offers tangible modelling advice for infectious disease analysts, suggesting the use of either model for endemic diseases. For epidemic outbreaks, or scenarios with varying population size, structured phylodynamic models relying on the Kingman coalescent with constant population size should be avoided as they can lead to inaccurate estimates of the migration rate. Instead, coalescent models accounting for varying population size or birth–death models should be favoured. Importantly, our study emphasises the value of directly capturing exponential growth dynamics which could be a useful enhancement for structured coalescent models.

MT-Net: Single image dehazing based on meta learning, knowledge transfer and contrastive learning

Single image dehazing is becoming increasingly important as its results impact the efficiency of subsequent computer vision tasks. While many methods have been proposed to address this challenge, existing dehazing approaches often exhibit limited adaptability to different types of images and lack future learnability. In light of this, we propose a dehazing network based on meta-learning, knowledge transfer, and contrastive learning, abbreviated as MT-Net. In our approach, we combine knowledge transfer with meta-learning to tackle these challenges, thus enhancing the network’s generalization performance. We refine the structure of knowledge transfer by introducing a two-phases approach to facilitate learning under the guidance of teacher networks and learning committee networks. We also optimize the negative examples of contrastive learning to reduce the contrast space. Extensive experiments conducted on synthetic and real datasets demonstrate the remarkable performance of our method in both quantitative and qualitative comparisons. The code has been released on https://github.com/71717171fan/MT-Net.

Experimental study of thermoconcentration convection in air–water and air–undecane mixtures

A quantitative experimental comparison was conducted between thermal convection in dry air and thermoconcentration convection in two gas mixtures: air–water vapor and air–undecane vapor, within the temperature range of 0–80 °C at normal atmospheric pressure. Convection in these mixtures is driven by temperature and concentration gradients of water (or undecane) vapor in the air. The stationary thermoconcentration convection is accompanied by continuous phase transitions of the fluids. The quantitative results of the experiments are represented in terms of the Nusselt number Nu and the effective Rayleigh number RaE, which is the sum of the thermal RaT and concentration RaC Rayleigh numbers. Quantitative laboratory measurements were performed using the thermocouple method and were supplemented with qualitative data from visual monitoring of transparent fluid flows using holographic interferometry. The cubic and quadratic temperature dependencies of RaCRaT−1 were determined experimentally for moist air and for the air–undecane vapor mixture, respectively. The significant role of moisture phase transitions in air convection is established. Neglecting these effects at 25 °C and using the ordinary RaT instead of actual RaE would result in an error exceeding 30%. At 38 °C, this error would increase to nearly 100%. At around 80 °C, thermoconcentration convection becomes almost entirely concentration-driven, as the high molecular disordered thermal motion is suppressed by the ordered convective motion generated by evaporation and condensation of water on the opposite heat exchangers of the convective cell.

Long-term interaction of metals and phosphate with ferrihydrite in artificial seawater and implications for past and present environments

The FeIII hydroxide ferrihydrite (Fh) is highly reactive towards dissolved metals and other aqueous compounds. This reactivity suggests a possible role for Fh in environmental remediation and in controlling ambient concentrations of metals and nutrients in both modern and ancient aqueous environments. Though the reactivity of Fh towards a variety of aqueous compounds has been determined in previous studies, its reactivity under seawater-like conditions has not been systematically explored. Since solution chemistry can have a profound effect on the uptake of metals and oxyions through its effects on the surface chemistry of Fh and the speciation of metals in solution, the dearth of experiments under seawater-like conditions translates into a knowledge gap of metal-Fh interactions in natural marine systems. Furthermore, metal- and nutrient-Fh interactions have been investigated under dissimilar conditions, making a quantitative comparison of these interactions difficult. Lastly, the fate of the aqueous metals and nutrients taken up by Fh upon its aging has been examined in only a few studies and mostly for a duration up to ∼8 months.We bridged these gaps in a series of adsorption and co-precipitation experiments of various metals and phosphate with Fh, in seawater-analog solutions, at circumneutral pH (pH 7.5 and 8.0) and 25 °C. We quantified the effect of interaction with Fh on the aqueous concentrations of CdII, CoII, CrVI, CuII, MnII, MoVI, NiII, VV, UVI, ZnII, and phosphate (PO43−). The experimental results are provided as uptake percentages (quantified as the metal:Fe ratio in the solid phase relative to the metal:Fe ratio added) at different metal:Fe ratios and as a series of partition coefficients of the studied metals and PO43− between aqueous solution and Fh. Additionally, aging experiments of up to ∼4 years in duration were used to determine the potential effects of grain coarsening, surface modification and mineral transformation on the uptake of the metals and PO43−. Uptake of CrVI, MoVI and UVI was negligible in both the adsorption and co-precipitation experiments. Uptake of VV and PO43− by co-precipitation was as much as twice their uptake by adsorption, and we suggest that stabilization of colloidal Fh with a large surface area explains these findings. For CuII, NiII, CoII, MnII, and CdII differences in uptake between the co-precipitation and adsorption experiments were less pronounced, and we ascribe these differences to relatively minor incorporation of these metals into Fh. No significant transformation of Fh to more stable phases was observed under our experimental conditions and duration. Nevertheless, the uptake of several metals and phosphate was affected by Fh aging. Approximately 75% of the PO43− initially taken up by co-precipitation with Fh was released, as was approximately 30% of the VV. A pronounced increase in the uptake of MnII may be related to its oxidation and precipitation as MnIII,IV oxides. For other metals the changes in uptake were less pronounced.We discuss the mechanisms of metal and PO43− uptake by Fh, the effects of solution composition on uptake, and the implications of our findings for modern and ancient natural environments and for environmental remediation.

FLAIM: A reduced volume ignition model for the compression and thermonuclear burn of spherical fuel capsules

We present the “First Light Advanced Ignition Model” (FLAIM), a reduced model for the implosion, adiabatic compression, volume ignition and thermonuclear burn of a spherical DT fuel capsule utilising a high-Z metal pusher. FLAIM is characterised by a highly modular structure, which makes it an appropriate tool for optimisations, sensitivity analyses and parameter scans. One of the key features of the code is the 1D description of the hydrodynamic operator, which has a minor impact on the computational efficiency, but allows us to gain a major advantage in terms of physical accuracy. We demonstrate that a more accurate treatment of the hydrodynamics plays a primary role in closing most of the gap between a simple model and a general 1D rad-hydro code, and that only a residual part of the discrepancy is attributable to the heat losses. We present a detailed quantitative comparison between FLAIM and 1D rad-hydro simulations, showing good agreement over a large parameter space in terms of temporal profiles of key physical quantities, ignition maps and typical burn metrics.

STRATEGIC MANAGEMENT: FROM THE DIGITALIZATION OF THE CONSTRUCTION INDUSTRY TO THE DEVELOPMENT OF THE HOUSING MARKET UNDER THE TERMS OF FINANCIAL LEASING

In the article, a study was conducted on the consideration of the advantages and possibilities of implementing the process of digitalization of the construction sector in the context of strategic management, taking into account the possibilities and need for effective interaction and interconnection of the state and business structures, taking this into account when developing effective mechanisms for its implementation in order to provide the population with housing on terms of financial leasing. The purpose of the article is the development of theoretical approaches and the development of practical recommendations for increasing the effectiveness of strategic management of the construction sector in the context of its digitalization, outlining the relationship with the real estate market, taking into account the prospects of providing the population with housing under the terms of financial leasing. The methodological basis of the article is a number of methods that ensure the reliability of the obtained results and conclusions, in particular, such as: monographic, logical, descriptive-analytical, analysis, synthesis, system approach, theoretical generalization, observation, quantitative and qualitative comparison. The article examines the digitalization of the construction sector of Ukraine in the context of strategic management as a vital necessity to ensure recovery in the post-war and post-war periods, as an important stage in the development of infrastructure and the economy in general. Attention is focused on the importance of developing a program of actions taking into account the implementation of digitization mechanisms, taking into account the interrelationship and dependence of the effective functioning of the economy on the level of development of innovative technologies, regulatory and legal support, the field of education, in particular higher education, and the development of public-private partnerships. The advantages and disadvantages of digitalization of the construction sphere of Ukraine are considered, taking into account the challenges that this sphere faces in modern business conditions. The role of digitization in the housing market under the terms of financial leasing and the main aspects in which digital technologies change this market are determined.

Photoreceptor Characteristics in Diabetic Retinopathy vs Controls Using Adaptive Optics Imaging: Systematic Review

Purpose: To assess the differences in morphological photoreceptor outcomes measured using adaptive optics (AO)–assisted imaging between individuals with diabetes or prediabetes and healthy controls. Methods: A systematic search was conducted across MEDLINE, Embase, and Cochrane databases from January 2000 to June 2023. Studies that used AO-assisted imaging modalities to quantitatively compare photoreceptor outcomes in patients with diabetes or prediabetes with healthy controls were included. Results: Eleven studies consisting of 551 eyes were included. Most studies reported significant differences in photoreceptor outcomes between diabetic and healthy populations, particularly as diabetic retinopathy (DR) severity increased. Cone regularity was the most sensitive parameter for detecting significant differences between groups. AO imaging was less reliable in distinguishing individuals with diabetes without DR or with mild DR severity from controls. Conclusions: AO imaging showed promise in detecting significant differences associated with diabetes and DR, in particular with increasing disease severity. Further research is warranted to assess AO’s utility as a diabetes and DR screening tool. Standardizing imaging protocols in future studies is recommended to allow for more direct quantitative comparisons. These findings highlight the current evidence on photoreceptor changes in patients with diabetes and the potential of AO in advancing diabetic eye care.

Predator perception of aposematic and cryptic color morphs in two Oophaga species.

Animals that are toxic often advertise their unprofitability to potential predators through bright aposematic colors while cryptic ones blend in with their natural background to avoid predators. In the poison dart frogs, Oophaga pumilio and O. granulifera, some populations in Costa Rica and Panama display cryptic green and aposematic red color morphs. We herein used reflectance spectra from the dorsum of red and green morphs of these frogs to estimate their perception by the visual systems of three potential predators (birds, lizards, and crabs) against three natural backgrounds (leaves, trunks and leaf litter). Statistical analyses revealed no strong differences in color contrast against backgrounds between the two frog species. However, strong effects of frog morph, predator, background, and their interactions were observed. When viewed against diverse backgrounds, red frogs of both Oophaga species are more color conspicuous to birds and Anoline lizards than to crabs. A strong effect of species was observed on luminance contrast. Concerning the latter, green frogs particularly in O. granulifera appear more conspicuous than red frogs, while birds perceive higher brightness contrasts than lizards or crabs. Our results further support the importance of birds and lizards as Oophaga predators and provide a first quantitative comparison of conspicuousness between these two frog species.

Qualitative and quantitative reservoir characterization using seismic inversion based on particle swarm optimization and genetic algorithm: a comparative case study

Accurate reservoir characterization is necessary to effectively monitor, manage, and increase production. A seismic inversion methodology using a genetic algorithm (GA) and particle swarm optimization (PSO) technique is proposed in this study to characterize the reservoir both qualitatively and quantitatively. It is usually difficult and expensive to map deeper reservoirs in exploratory operations when using conventional approaches for reservoir characterization hence inversion based on advanced technique (GA and PSO) is proposed in this study. The main goal is to use GA and PSO to significantly lower the fitness (error) function between real seismic data and modeled synthetic data, which will allow us to estimate subsurface properties and accurately characterize the reservoir. Both techniques estimate subsurface properties in a comparable manner. Consequently, a qualitative and quantitative comparison is conducted between these two algorithms. Using two synthetic data and one real data from the Blackfoot field in Canada, the study examined subsurface acoustic impedance and porosity in the inter-well zone. Porosity and acoustic impedance are layer features, but seismic data is an interface property, hence these characteristics provide more useful and applicable reservoir information. The inverted results aid in the understanding of seismic data by providing incredibly high-resolution images of the subsurface. Both the GA and the PSO algorithms deliver outstanding results for both simulated and real data. The inverted section accurately delineated a high porosity zone (>20%\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$>20\\%$$\\end{document}) that supported the high seismic amplitude anomaly by having a low acoustic impedance (6000–8500 m/s∗\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$*$$\\end{document} g/cc). This unusual zone is categorized as a reservoir (sand channel) and is located in the 1040–1065 ms time range. In this inversion process, after 400 iterations, the fitness error falls from 1 to 0.88 using GA optimization, compared to 1 to 0.25 using PSO. The convergence time for GA is 670,680 s, but the convergence time for PSO optimization is 356,400 s, showing that the former requires 88%\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$88\\%$$\\end{document} more time than the latter.

Distribution of tetracyclines and sulfonamides resistance genes around a smallholder pig farm: Modeling and attribution

Livestock farm is a major source of antibiotics and antibiotic resistance genes (ARGs) pollution. ARGs can directly enter the environment through runoff and air deposition. The impact extent and the driving factors require further investigation to inform effective policies and actions to mitigate their spread. This study investigated a smallholder pig farm and its surrounding areas to understand the spread of ARGs. Topsoil samples were collected from 56 different sites within one kilometer of the farm, and a comprehensive analysis was conducted to reveal effects of soil properties, antibiotic residues, microbiome, mobilome on the variation of typical ARGs. The results confirmed that the ARGs reduced exponentially with increasing distance from the farm, with a goodness of fit (R2) of 0.7 for total ARGs. For tetracyclines (TC) and sulfonamides (SA) resistance genes, the fitting R2 exceeded 0.9. Model estimates allowed for quantitative comparisons of in-farm increments, out-farm background levels, and spread abilities of ARGs with distinct resistance mechanisms. SA-specific resistance genes (SRGs, 0.097 copies/16S rRNA gene) and TC-specific resistance genes (TRGs, 0.036 copies/16S rRNA gene) showed higher within-farm increases compared to multidrug resistance genes (MDRGs, 0.020 copies/16S rRNA gene). MDRGs, however, had a higher background level and a greater impact distance (0.18 km, 4.4 times the farm radius). Additionally spread abilities of TRGs varied by resistance mechanism, with ribosome protection proteins showing greater spread than TC inactivating enzymes and TC efflux pumps, likely due to different fitness costs. Correlation analysis and structural equation modeling indicated that changes in bacterial community composition and mobilome are primary factors influencing ARGs variation during their spread. Abiotic factors like soil nutrients and antibiotics also selectively enriched ARGs within the farm. These findings provide insights into the ARGs dissemination and could inform strategies to prevent their spread from smallholder livestock farms.

How does urbanization affect natural selection?

Abstract Urbanization is one of the most significant contributors to the Anthropocene, and urban evolutionary ecology has become an important field of research. While it is commonly assumed that cities impose new and stronger selection, the contradictory assertion that selection may be relaxed in cities is also frequently mentioned, and overall, our understanding of the effects of urbanization on natural selection is incomplete. In this review, we first conduct a literature search to find evidence for patterns of natural selection on phenotypic traits including morphology, physiology, behaviour and life history, in urban and non‐urban populations of animals and plants. This search reveals that coefficients of natural selection in the context of urbanization are scarce (n = 8 studies providing selection gradients/differentials that include a total of n = 200 coefficients) and a lack of standardized methods hinders quantitative comparisons across studies (e.g. with meta‐analysis). These studies, however, provide interesting insight on the agents shaping natural selection in cities and improve our mechanistic understanding of selection processes at different spatial scales. We then perform a second literature search to review genomic studies assessing selection intensity in cities, on the genome of non‐human natural populations. While this search returns 383 articles, only 34 of these truly investigate footprints of selection associated with urbanization, and only one study provides urban genetic selection coefficients. Here again, we find highly heterogeneous approaches, yet some studies provide strong evidence of genomic footprints of urban adaptation. In neither the phenotypic nor genomic literature review were we able to quantitatively assess natural selection across urban versus non‐urban habitats. Thus, we propose a roadmap of how future studies should provide standardized metrics to facilitate mega‐ or meta‐analyses and explore generalized effects of urbanization on selection. Read the free Plain Language Summary for this article on the Journal blog.

On the significance of the different geometrical and dosimetric parameters in microbeam and minibeam radiation therapy a retrospective evaluation.

Spatially Fractionated Radiation Therapy (SFRT) is an unconventional therapeutic approach with the potential to disrupt the classical paradigms of conventional radiation therapy. The high spatial dose modulation in SFRT is believed to activate distinct radiobiological mechanisms which lead to remarkable increases in normal tissue tolerance. To make optimal use of SFRT and its benefits, a deeper understanding of the biological response and its relationship with the complex dosimetric and geometric components of SFRT is essential. A retrospective evaluation of preclinical studies was conducted to gain insight into the dosimetric and geometric parameters that are most correlated with normal tissue response. Current literature evaluates the response of tissue to MBRT and MRT according to various end points, e.g. the level of desquamation, degree of necrosis, or the amount of malcalcification. A set of metrics was developed to allow a quantitative comparison of these results. The strongest correlations were observed with the doses in both the peaks and valleys as well as the ratio of the area covered by the peak over the total area. This emphasises the geometry of the beam. MBRT challenged previous uniform dose-distribution paradigms by highlighting the critical role of Peak Dose alongside Valley Dose in tissue sparing whereas MRT underscores the significant influence of geometric beam parameters on tissue preservation. The data exhibits variability in the results obtained using different animal models and endpoints and additional research is warranted to explore the trends observed in this study under controlled conditions.

SpaTopic: A statistical learning framework for exploring tumor spatial architecture from spatially resolved transcriptomic data.

Tumor tissues exhibit a complex spatial architecture within the tumor microenvironment (TME). Spatially resolved transcriptomics (SRT) is promising for unveiling the spatial structures of the TME at both cellular and molecular levels, but identifying pathology-relevant spatial domains remains challenging. Here, we introduce SpaTopic, a statistical learning framework that harmonizes spot clustering and cell-type deconvolution by integrating single-cell transcriptomics and SRT data. Through topic modeling, SpaTopic stratifies the TME into spatial domains with coherent cellular organization, facilitating refined annotation of the spatial architecture with improved performance. We assess SpaTopic across various tumor types and show accurate prediction of tertiary lymphoid structures and tumor boundaries. Moreover, marker genes derived from SpaTopic are transferrable and can be applied to mark spatial domains in other datasets. In addition, SpaTopic enables quantitative comparison and functional characterization of spatial domains across SRT datasets. Overall, SpaTopic presents an innovative analytical framework for exploring, comparing, and interpreting tumor SRT data.