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The development of simplified surrogate mixtures able to replicate combustion-related behaviors of chemically complex fuels is essential for their simulation with computational tools, a key step towards the design of high-efficiency and low-emission combustion applications. This work proposes to use the isolated droplet configuration as a benchmark to formulate and validate surrogates that capture the vaporization and soot production characteristics of a first-fill diesel and a diesel-biodiesel mixture. To that end, droplet vaporization experiments and a multicomponent model were coupled to produce blends matching the evaporation behavior, whereas the soot tendency was incorporated through tests at the ASTM D1322 smoke point lamp and the Oxygen Extended Sooting Index (OESI). The so-obtained surrogate blends were subsequently validated for both characteristics. Their evaporation curves proved to match remarkably well those obtained for the target fuels, with noticeable improvements when increasing the number of compounds in the mixture. As for the sooting behavior, the proposed blends achieved a good emulation in terms of the design parameter (OESI), confirming the validity of the proposed methodology. On the other hand, an additional and independent validation of the sooting propensity through the quantification of the mass of soot produced by isolated droplets under a high-temperature and reducing atmosphere revealed significantly higher soot yields for the surrogates when compared to the target fuels. These results highlight the relevance of the configuration used when designing and validating surrogates, since the same blends can provide substantial differences when evaluated through different sooting indices. [ABSTRACT FROM AUTHOR]

• Surrogacy using assisted reproductive technology is increasingly popular. • Surrogates have medium to high education, are employed and have independent income. • Surrogates have medium socio-economic status and above-average income. • Women state that their primary motivation for becoming a surrogate is prosocial. • Women become surrogates of their own free will. What is the profile of women in the USA who become surrogates, and what is their power of decision and motivations? This quantitative study was performed with 231 participants in the USA, given the country's long history of surrogacy, to help clarify the profile of women who become surrogates, their power of decision and motivations. Descriptive and multivariate cluster analyses showed that women who become surrogates earn above the average income for their state of residency, have a high level of education, have health insurance, are employed, and decide to become a surrogate for prosocial/altruistic reasons. In contrast to the premise of both radical feminism and ultra-conservative Catholicism, this study found that altruism and empathy are the primary motivations for participating in surrogacy processes, and that a woman's decision to become a surrogate is not motivated by social conditioning relating to poverty or social status. [ABSTRACT FROM AUTHOR]

The shape design and optimization of bluff decks prone to aeroelastic phenomena require emulating the fluid-structure interaction parameters as a function of the body shape and the oscillation frequency. This is particularly relevant for long- and medium-span bridges equipped with single-box decks that are far from being considered streamlined and for other girder typologies such as traditional truss decks and modern twin- and multi-box decks. The success of aero-structural design frameworks, which are inherently iterative, relies on the efficient and accurate numerical evaluation of the wind-induced responses. This study proposes emulating the fluid-structure interaction parameters of bluff decks using surrogate modeling techniques to integrate them into aero-structural optimization frameworks. The surrogate is trained with data extracted from forced-vibration CFD simulations of a typical single-box girder to emulate the values of the flutter derivatives as a function of the deck shape and reduced velocity. The focus is on deck configurations ranging from streamlined to bluff cross-sections and on low reduced velocities to capture eventual aerodynamic nonlinearities. The girder cross-section geometry is tailored based on its buffeting performance. This design tool is fundamental to finding the optimum balance between the structural and aeroelastic requirements that drive the design of bluff deck bridges. • A computational method for the aero-structural design of bluff decks is proposed. • An aeroelastic emulator enables deck shape variations including bluff geometries. • CFD simulations of force vibrations are used to extract the 18 flutter derivatives. • The sampling plan focuses on low reduced velocities to capture nonlinear aerodynamics. • A buffeting-resistant deck shape tailoring shows the performance of the methodology. [ABSTRACT FROM AUTHOR]

To obtain more accurate model parameters and improve prediction accuracy, we proposed a regularized Kriging model that penalizes the hyperparameter theta in the Gaussian stochastic process, termed the Theta-regularized Kriging. We derived the optimization problem for this model from a maximum likelihood perspective. Additionally, we presented specific implementation details for the iterative process, including the regularized optimization algorithm and the geometric search cross-validation tuning algorithm. Three distinct penalty methods, Lasso, Ridge, and Elastic-net regularization, were meticulously considered. Meanwhile, the proposed Theta-regularized Kriging models were tested on nine common numerical functions and two practical engineering examples. The results demonstrate that, compared with other penalized Kriging models, the proposed model performs better in terms of accuracy and stability. • We proposed the Theta-regularized Kriging model and considered three penalty terms: l 1 , l 2 , and Elastic-net. • Regularization was applied to the Gaussian process parameters of the Kriging model. • The regularization parameters were determined by the geometric search and cross-validation method. • Theta-regularized Kriging outperforms other regularized Kriging methods in accuracy and robustness. [ABSTRACT FROM AUTHOR]

Estimating long-term causal effects based on short-term surrogates is a significant but challenging problem in many real-world applications such as marketing and medicine. Most existing methods estimate causal effects in an idealistic and simplistic manner — disregarding unobserved surrogates and treating all short-term outcomes as surrogates. However, such methods are not well-suited to real-world scenarios where the partially observed surrogates are mixed with the proxies of unobserved surrogates among short-term outcomes. To address this issue, we develop our flexible method called LASER to estimate long-term causal effects in a more realistic situation where the surrogates are either observed or have observed proxies. In LASER, we employ an identifiable variational autoencoder to learn the latent surrogate representation by using all the surrogate candidates without the need to distinguish observed surrogates or proxies of unobserved surrogates. With the learned representation, we further devise a theoretically guaranteed and unbiased estimation of long-term causal effects. Extensive experimental results on the real-world and semi-synthetic datasets demonstrate the effectiveness of our proposed method. [ABSTRACT FROM AUTHOR]

This work is concerned with the construction of statistical surrogates for concurrent multiscale modeling in structures comprising nonlinear random materials. The development of surrogates approximating a homogenization operator is a fairly classical topic that has been addressed through various methods, including polynomial- and deep-learning-based models. Such approaches, and their extensions to probabilistic settings, remain expensive and hard to deploy when the nonlinear upscaled quantities of interest exhibit large statistical variations (in the case of non-separated scales, for instance) and potential non-locality. The aim of this paper is to present a methodology that addresses this particular setting from the point of view of probabilistic learning. More specifically, we formulate the approximation problem using conditional statistics, and use probabilistic learning on manifolds to draw samples of the nonlinear constitutive model at mesoscale. Two applications, relevant to inverse problem solving and forward propagation, are presented in the context of nonlinear elasticity. We show that the framework enables accurate predictions (in probability law), despite the small amount of training data and the very high levels of nonlinearity and stochasticity in the considered system. [ABSTRACT FROM AUTHOR]

[Display omitted] • The method can accurately validate the sanitation efficacy on the produce surface. • The CAT@L-PDMS mimics topographies and bacterial distribution on the leaf surface. • Sanitation efficacy can be predicted using FTIR spectra and machine learning. Washing and sanitation are vital steps during the postharvest processing of fresh produce to reduce the microbial load on the produce surface. Although current process control and validation tools effectively predict sanitizer concentrations in wash water, they have significant limitations in assessing sanitizer effectiveness for reducing microbial counts on produce surfaces. These challenges highlight the urgent need to improve the validation of sanitation processes, especially considering the presence of dynamic organic contaminants and complex surface topographies. This study aims to provide the fresh produce industry with a novel, reliable, and highly accurate method for validating the sanitation efficacy on the produce surface. Our results demonstrate the feasibility of using a food-grade, catalase (CAT)-immobilized biomimetic leaf in combination with vibrational spectroscopy and machine learning to predict microbial inactivation on microgreen surfaces. This was tested using two sanitizers: sodium hypochlorite (NaClO) and hydrogen peroxide (H 2 O 2). The developed CAT-immobilized leaf-replicated PDMS (CAT@L-PDMS) effectively mimics the microscale topographies and bacterial distribution on the leaf surface. Alterations in the FTIR spectra of CAT@L-PDMS, following simulated sanitation processes, indicate chemical changes due to CAT oxidation induced by NaClO or H 2 O 2 treatments, facilitating the subsequent machine learning modeling. Among the five algorithms tested, the competitive adaptive reweighted sampling partial least squares discriminant analysis (CARS-PLSDA) algorithm was the most effective for classifying the inactivation efficacy of E. coli on microgreen leaf surfaces. It predicted bacterial reduction on microgreen surfaces with 100% accuracy in both training and prediction sets for NaClO, and 95% in the training set and 86% in the prediction set for H 2 O 2. This approach can improve the validation of fresh produce sanitation processes and pave the way for future research. [ABSTRACT FROM AUTHOR]

Objective: This study sought to develop a decision aid with cartoon pictures and evaluate its effectiveness in increasing consistency between elderly individuals and their surrogates regarding end-of-life care.Methods: A pre-post quasi-experimental design was adopted using the Life Support Preferences Questionnaire. The intervention had two components: (1) increasing participants' knowledge of medical treatments related to end-of-life care, and (2) sharing their end-of-life wishes. The experimental group received an intervention, whereas the control group received usual care.Results: A total of 110 participants in 55 pairs of elderly individuals with average aged 86.4 and their surrogates (27 in the experimental group, 28 in the control group) were recruited from a veterans hospital in northern Taiwan. Nearly 90 % of elderly individuals were male. The multiple linear regression showed that the inconsistent gap between elderly individuals and their surrogates in the experimental group decreased 12 points than the control group after controlling the covariances (B = -12.116, p = 0.032).Conclusion: The intervention improved the consistency between elderly individuals and their surrogates regarding end-of-life care.Practice Implications: A decision aid with cartoon pictures may support the discussion of end-of-life care in older Asian populations. [ABSTRACT FROM AUTHOR]

Vascularised composite allograft (VCA) transplantation is now a feasible reconstructive option for patients who have suffered significant soft tissue injuries. However, despite numerous technical advances in the field over two decades, a number of challenges remain, not least the management of transplant rejection. Part of the difficulty faced by clinicians is the early recognition and prevention of acute rejection episodes. Whilst this is potentially easier in VCAs than solid organ transplants, due to their visible skin component, at present the only validated method for the diagnosis of acute rejection is histological examination of a tissue biopsy. The aim of this review article is to provide an evidence-based overview of progress in the field of VCA biomarker discovery, including immune cell subsets, immune cell effector pathways, and circulating markers of allograft damage, and to discuss future challenges in the field. [ABSTRACT FROM AUTHOR]

In Process Systems Engineering, computationally-demanding models are frequent and plentiful. Handling such complexity in an optimization framework in a fast and reliable way is essential, not only for generating meaningful solutions but also for providing decision support. Indeed, optimization results need to be obtained efficiently without compromising accuracy or solution quality. Surrogate models are a cheap way of replacing complex ones, while still capturing the intrinsic features that make them unique and valuable. In this work, a methodology to build surrogate models is developed. It combines a genetic algorithm with an active learning method, harvesting the benefits of both approaches — on the one hand leveraging nature-inspired optimization procedures that explore the optimization space area, and conversely a 'smart' approach to adding meaningful sample points to the training stage. The methodology, coined GA-AL, is tested and validated for chemical absorption of CO 2 in a biogas mixture inserted in a utility superstructure framework. Nine surrogate modes are tested, with Artificial Neural Networks, Random Forest and Kringing outperforming other approaches, assessed via four performance criteria. • The increasing complexity of simulation and optimization models requires the development of adequate surrogate models. • This work focused on the modeling and construction of surrogates, inserted in a superstructure-based optimization framework. • A novel genetic algorithm–active learning (GA-AL) approach for complex simulation models was developed and embedded in an optimization framework. • The newly proposed GA-AL approach proved to be efficient and adequate for building surrogate models, demonstrated in a biogas separation case study. • Nine surrogate models were tested. artificial neural networks, random forests, and standard kriging outperformed the other six. [ABSTRACT FROM AUTHOR]

• Community composition of other taxa changed consistently with bird communities and indicator species within farmlands. • Efficiency of different bird indices as bioindicators varied across landscapes and taxa. • Species richness, number of threatened and farmland birds were most selected indices. • 14 different indicator species were found for grasslands and crops. • European serin and Alpine accentor were the most selected indicator species. Biodiversity loss is a global issue, particularly in mountain regions, where land-use/land-cover and climate change dramatically impact on species and communities. Sound ecological research and up-to-date information on biodiversity are needed to support conservation efforts. However, this information is often difficult and costly to obtain. Therefore, bioindicators serve as surrogates to provide information on the entire biocenosis. Birds are considered excellent bioindicators as they occupy different ecological niches and trait spaces. We present a study about the efficiency of birds as bioindicators for the diversity of other taxa in a mountain region in the Central Alps. We surveyed bird communities at 115 sites across a gradient of different grasslands and crops and compared them with the diversity of other taxa (bats, butterflies, grasshoppers, arachnids, and vascular plants). We aimed to identify indicator bird species for grasslands and crops, to assess cross-community concordance between birds and other taxa, and to model the efficiency of bird indices and indicator species as bioindicators of the diversity across habitat types and taxa. We identified indicator bird species for different grassland and crop types and found that efficiency of bird indices and single species varied for habitat types and taxa. We highlight the importance of using carefully selected bioindicators in biodiversity monitoring and conservation planning, and the need for an integrated and interdisciplinary approach for biodiversity research. Moreover, by looking at a combination of different indices we can gain a more comprehensive understanding of ecosystem functioning. We also provide a framework for the use of bird-based monitoring programs and bird-derived indices to guide biodiversity conservation, and emphasise the importance of incorporating different bioindicators into biodiversity research and monitoring to provide a more comprehensive understanding of ecological biodiversity patterns and trends. [ABSTRACT FROM AUTHOR]

No empirical data are available on the healthcare experiences of surrogates during the COVID-19 pandemic. This study aimed to examine the impact of pandemic-control measures on surrogates' fertility, pregnancy and birthing experiences. Sampling frame included eligible surrogates who were actively involved in a surrogacy process at an academic IVF centre during the pandemic (03/2020 to 02/2022). Data were collected between 29/04/2022 and 31/07/2022 using an anonymous 85-item online survey that included twelve open-ended questions. Free-text comments were analysed by thematic analysis. The response rate was 50.7% (338/667). Of the 320 completed surveys used for analysis, 609 comments were collected from 206 respondents. Twelve main themes and thirty-six sub-themes grouped under 'vaccination', 'fertility treatment', 'pregnancy care', and 'surrogacy birth' were identified. Three in five surrogates found the control measures highly or moderately affected their surrogacy experiences. Themes involving loneliness and isolation frequently emerged when essential surrogacy support was restricted by the visitor protocols implemented at healthcare facilities. Our findings show that restricting or limiting intended parents' in-person involvement increased surrogates' feelings of isolation and made the overall surrogacy experience less rewarding and fulfilling. Furthermore, the childbirth experiences of surrogates were mostly negative, suggesting that hospitals were ill-equipped to manage all births, including surrogacy births, during the pandemic. Our findings highlight the needs to rethink how surrogacy care and maternity services could be strengthened to better serve the needs of surrogates during times of public health crises, such as COVID-19, while still allowing for risk mitigation and maximising patient safety. [ABSTRACT FROM AUTHOR]

• The delta smelt is endemic to the Sacramento-San Joaquin Delta. • Management has focused on the low-salinity zone as a proxy for delta smelt habitat. • But the location of the low-salinity zone is a poor predictor of the distribution of the fish. • Conservation efforts have failed to arrest the decline of delta smelt. • That should remind resource managers that surrogates and proxies should be validated. The use of surrogates in conservation planning for at-risk species is both a necessary and a fraught practice. Here we assess the use of the position of the low-salinity zone in California's Sacramento-San Joaquin Delta as a surrogate for the extent and quality of habitat available to the imperiled delta smelt. The U.S. Fish and Wildlife Service issued a biological opinion and incidental take statement under the Endangered Species Act analyzing the impacts of ongoing operation of two large water infrastructure projects on the delta smelt. The Service's analysis and the conservation actions it imposed are based on the assumption that the low-salinity zone can serve as a "surrogate indicator" for delta smelt habitat. We demonstrate that available scientific information on the species countermands use of the low-salinity zone to represent delta smelt habitat in conservation planning for the species, and that the U.S. Fish and Wildlife Service erred by assuming the existence of a surrogate relationship absent validation using the best available scientific information. Notably, large expanses within the low-salinity zone are unoccupied by delta smelt and the species consistently occurs outside of it. This case serves to remind scientists of the dysfunction between a consensus in the scientific literature that calls for analytical validation prior to the use of species surrogates and habitat proxies, and the commonplace practice of using surrogates and proxies based on surmise and assertion. [ABSTRACT FROM AUTHOR]

Abstract Surrogate fuels aim to reproduce real fuel combustion characteristics in order to enable predictive simulations and fuel/engine design. In this work, surrogate mixtures were formulated for three diesel fuels (Coryton Euro and Coryton US-2D certification grade and Saudi pump grade) and two jet fuels (POSF 4658 and POSF 4734) using the minimalist functional group (MFG) approach, a method recently developed and tested for gasoline fuels. The diesel and jet fuel surrogates were formulated by matching five important functional groups, while minimizing the surrogate components to two species. Another molecular parameter, called as branching index (BI), which denotes the degree of branching was also used as a matching criterion. The present works aims to test the ability of the MFG surrogate methodology for high molecular weight fuels (e.g., jet and diesel). 1H Nuclear Magnetic Resonance (NMR) spectroscopy was used to analyze the composition of the groups in diesel fuels, and those in jet fuels were evaluated using the molecular data obtained from published literature. The MFG surrogates were experimentally evaluated in an ignition quality tester (IQT), wherein ignition delay times (IDT) and derived cetane number (DCN) were measured. Physical properties, namely, average molecular weight (AMW) and density, and thermochemical properties, namely, heat of combustion and H/C ratio were also compared. The results show that the MFG surrogates were able to reproduce the combustion properties of the above fuels, and we demonstrate that fewer species in surrogates can be as effective as more complex surrogates. We conclude that the MFG approach can radically simplify the surrogate formulation process, significantly reduce the cost and time associated with the development of chemical kinetic models, and facilitate surrogate testing. [ABSTRACT FROM AUTHOR]

Abstract Robust surrogate formulation for gasoline fuels is challenging, especially in mimicking auto-ignition behavior observed under advanced combustion strategies including boosted spark-ignition and advanced compression ignition. This work experimentally quantifies the auto-ignition behavior of bi- and multi-component surrogates formulated to represent a mid-octane (Anti-Knock Index 91.5), full boiling-range, research grade gasoline (Fuels for Advanced Combustion Engines, FACE-F). A twin-piston rapid compression machine is used to achieve temperature and pressure conditions representative of in-cylinder engine operation. Changes in low- and intermediate-temperature behavior, including first-stage and main ignition times, are quantified for the surrogates and compared to the gasoline. This study identifies significant discrepancies in the first-stage ignition behavior, the influence of pressure for the bi- to ternary blends, and highlights that better agreement is achieved with multi-component surrogates, particularly at lower temperature regimes. A recently-updated detailed kinetic model for gasoline surrogates is also used to simulate the measurements. Sensitivity analysis is employed to interpret the kinetic pathways responsible for reactivity trends in each gasoline surrogate. [ABSTRACT FROM AUTHOR]

Abstract Alkylbenzenes are major aromatic constituents of real transportation fuels and important surrogate components. In this study, the structural impact of nine alkylbenzenes on their ignition characteristics is experimentally and computationally investigated with particular emphasis on the blending effect with significantly more reactive normal alkanes. Experimental comparisons of mono-alkylbenzenes (toluene, ethylbenzene, n-propylbenzene, iso-propylbenzene) from a modified CFR engine showed that the difference in pure alkylbenzene reactivity significantly diminished when blended with n-heptane, as the strength of the radical scavenging effect of all three alkylbenzenes is similar. Among C 8 H 10 isomers, the reactivity of pure ethylbenzene and o-xylene and their blends with n-heptane showed a complex competing effect between the difference in C H bond energy and the existence of intermediate/low-temperature chemistry caused by adjacent methyl pairs. A similar structural impact was also observed for C 9 H 12 isomers and their blends with n-heptane, while the influence of C H bond energy was more noticeable than C 8 H 10 molecules. Kinetic simulations of the alkylbenzene/n-heptane blends highlighted the effect caused by adjacent methyl pairs that is referred to as the "ortho effect". Analysis of ethylbenzene and o-xylene showed that o-xylene's intermediate/low-temperature pathways initiated by benzylperoxy radical – benzylhydroperoxide isomerization (RO2 – QOOH) produce additional active radicals such as OH and CH 2 O, which accelerates the oxidation chemistry of more reactive n-heptane. This study provides knowledge on the blending effect of alkylbenzene compounds with n-heptane on their ignition characteristics that is useful to develop surrogates that can better mimic the reactivity of real fuels. [ABSTRACT FROM AUTHOR]

• Copolymers-modified microsphere is representative Cryptosporidium surrogate. • Alum and PACl have comparable surrogate log removal capacity. • Higher dose of PolyDADMAC leads to higher surrogate log removal. • Deep bed filter contributes to higher surrogate log removal. Pilot-scale direct filtration challenge experiments were conducted to determine the impact of chemical pretreatment and filter design on the removal of Cryptosporidium surrogates dosed into the filter influent water at low temperatures (Average 0.5 °C). Copolymers-modified microspheres were identified as representative Cryptosporidium oocysts surrogates based on our previous findings and were used to evaluate the oocysts filtration removal at this pilot-scale study. The operational parameters examined included coagulant type (aluminum sulfate (alum) versus polyaluminium chloride (PACl)), filter aid polymer type (polyamine Magnafloc® LT-7981 versus poly(Dimethyl Diallyl Ammonium Chloride) (polyDADMAC) Magnafloc® LT-7995) and dose (0.5 versus 2.0 mg/L), and filter configuration (regular versus deep bed filters). The study found that higher Cryptosporidium surrogate removal was associated with higher polymer dose (2 mg/L) of polyDADMAC polymer and the deep bed filter configuration. The difference in surrogate removal between PACl and alum was no significant at cold temperature conditions tested. The deep bed filters were associated with higher surrogate removal, while exhibiting lower rates of flow reduction and longer filter run time. This work emphasizes the importance of optimizing chemical pretreatment and filter configuration for removing surrogates of Cryptosporidium oocysts in cold-water conditions in granular media water filtration processes. This pilot-scale study also demonstrated the exceed 2.5-log removal of Cryptosporidium surrogates (required from Guideline for Canadian Drinking Water Quality) can be achieved in the direct filtration during Edmonton cold-water condition when the pretreatment processes are optimized using 0.454 mg/L of alum as Al with addition of 0.5 mg/L poly DADMAC. [ABSTRACT FROM AUTHOR]

Abstract This contribution explores the effect of nanoparticles of iron (III) oxide (Fe 2 O 3) on the combustion of coal surrogate, i.e., anisole, identifying the changes in ignition features as well as the occurrence of persistent organic pollutants in the initiation channels. The method applies packed-bed reactor coupled with Fourier transform infrared (FTIR) spectroscopy to quantitate the ignition temperature under typical fuel-rich conditions, in-situ electron paramagnetic resonance (EPR) to elucidate the formation of environmentally-persistent free radicals (EPFR), diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) to monitor the chemisorption of organic substrates on the nanoparticles, as well as X-ray diffraction for particles characterisation (PXRD). We employ cluster-based quantum mechanical calculation to map the reaction pathway within the scope of the density functional theory. The results of Fe 2 O 3 -mediated combustion of anisole depict an excessive reduction in ignition temperature from 500 °C around 220 °C at λ = 0.8. As confirmed both from EPR and DRIFTS measurements, the chemisorption of anisole on α -Fe 2 O 3 surfaces follows the direct dissociation of the O–CH 3 (and OCH 2 –H), leading to the formation of surface-bound phenoxy radicals at temperatures as low as 25 °C and incurring an estimated energy barrier of E a = 18 kJ mol−1 and a preexponential factor of A = 2.7 × 1012 M−1 s−1. This insight applies to free-radical chain reactions that induce spontaneous fires of coal, as coal comprises ferric oxide nanoparticles, and equally to coexistence of aromatic fuels with thermodynamically reactive Fe 2 O 3 surface, e.g., in fly ash, at the cooled-down tail of combustion stacks. [ABSTRACT FROM AUTHOR]

Abstract Substitute species (common species used to represent endangered species) are used to evaluate a range of conservation strategies globally. However, the effectiveness of this approach has not been empirically evaluated. We leveraged a large-scale habitat restoration experiment to test the validity of the substitute species concept. We selected a common butterfly, Satyrodes appalachia , that is on first inspection as near a substitute as possible - it is closely related to, overlaps in distribution, habitat requirements, host use, and life history with Neonympha mitchellii francisci , an endangered butterfly. We integrated small-scale measures of behavior, habitat preference, and demography of both species in our test, demonstrating that subtle differences between two species cause the substitute relationship to fail. Despite nearly identical habitat requirements, we found the endangered butterfly used different host plants, had higher larval survival in restored sites, and was found in more open habitat than the common butterfly. These differences added up to differences in abundances; the endangered species was more abundant than the common species in restored sites, the opposite was true in un-restored sites. Management decisions based on unvalidated substitute species run the risk of doing more harm than good for endangered species conservation. Instead, using experiments to evaluate a target species' response to management will result in effective recovery strategies. Highlights • Different responses to restoration from two similar butterflies reveal the limits of substitute species in conservation • Management decisions based on unvalidated substitutes likely do more harm than good for conservation • Best practice is to use carefully designed experiments to study endangered species directly [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • O 3 :DOC ratios up to 2 are not effective for significant removal of O 3 -resistant MPs. • Two-stage models based on R OHO3 allow complete performance description of ozonation. • R OHO3 concept can be useful for prediction of O 3 -recalcitrant species removal. • A novel method based on UVA 254 monitoring is proposed for removal prediction. Abstract Although ozonation is nowadays recognized as one of the most efficient technologies for micropollutants abatement in municipal wastewater effluents, several of the compounds potentially present in those waters exhibit a strong resistance to direct ozone oxidation. In addition, the real-time control of the removal process is still challenging. In this work, the abatement of ozone-recalcitrant micropollutants during wastewater ozonation of six different wastewater effluents was explored using the pesticide acetamiprid as hydroxyl radical (OH) probe. By means of this data, the oxidation efficiency (i.e. , hydroxyl radical exposure per consumed ozone) could be described by means of a two-stage model based on the R OHO3 concept. This was possible using a semi-continuous bubbling ozone contactor in all experiments, which permitted the inclusion of the ozone mass balance in the model. R OHO3 values of (1.53–7.60)·10−7 s for initial ozonation stage and (0.61–2.95)·10−6 s for the secondary stage were obtained allowing the characterization and comparison of the process performance in a wide range of effluent qualities, including water matrices with a high content of dissolved and particulate organic matter (total organic carbon (TOC), dissolved organic carbon (DOC) and turbidity tested ranges: 6.7–50 mg C L−1, 6.6–27.6 mg C L−1 and 0.3–28.6 NTU, respectively). Finally, a surrogate strategy involving OH exposure estimation by means of ultraviolet absorbance at 254 nm (UVA 254) measurements was proposed based on the R OHO3 concept, and by means of its application the removal of atrazine and ibuprofen in six different wastewaters could be rightly predicted (R2 > 0.98). [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The antioxidant properties of phenolic surrogates of lignin depolymerisation are evaluated. • Five various tests were performed on large ranges of concentrations. • Phenolic compounds present good reducing capacity and radical scavenging activity. • Phenolic compounds are not effective transition metal ions chelators. Abstract The thermochemical conversion of biomass (wood, straw, etc.) provides bio-oils containing some molecules with antioxidant properties and used in pharmaceutical or cosmetic industries. In this work, five different antioxidant tests were performed on eight phenolic surrogates of lignin depolymerisation mostly found in lignin bio-oils: phenol, guaiacol, syringol, pyrocatechol, o-, m-, p-cresol and vanillin. Results were compared with reference molecules in order to classify the phenolic compounds towards each antioxidant mechanism (i.e. iron or copper chelating capacity, radical scavenging capacity, reducing power and response to the Folin-Ciocalteu's reagent). The studied phenolic compounds do not present high transition metal chelation ability but they exhibit good reducing power and radical scavenging activity. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Copolymers-modified microspheres are representative Cryptosporidium surrogates. • They resemble the zeta potential and hydrophobicity of Cryptosporidium oocysts. • They have similar deposition kinetics as Cryptosporidium oocysts. • They also demonstrate similar transport behaviors in lab-scale filtration. Abstract Cryptosporidium , a waterborne protozoan pathogen that can cause gastrointestinal illness, is often found in surface waters that are used to supply drinking water. Filtration is a major process to remove Cryptosporidium in drinking water treatment. However, interactions between oocysts and filter media are still unclear and no satisfactory surrogates have been identified for quantifying their filtration removal in porous media. In the present study, polystyrene microsphere with a size, density, and shape similar to Cryptosporidium was modified with glycoprotein or synthesized biomolecules to mimic the surface properties of live Cryptosporidium oocyst. Deposition kinetics between live Cryptosporidium /modified microspheres and filter media were studied at the molecular scale using a quartz crystal microbalance with dissipation monitoring (QCM-D) and at the laboratory-scale using sand-packed columns. Both QCM-D and column experiments underlined the importance of Cryptosporidium surface charge and hydrophobicity on their attenuation and transport in porous media. As compared to live Cryptosporidium , glycopolymer and zwitterionic polymer co- odified polystyrene microspheres (later called copolymers-modified microspheres) represent comparable surface properties, adsorption kinetics on filter surfaces, and transport and deposition behaviors in filter columns; hence were selected as appropriate Cryptosporidium surrogates. This study improves our understanding on how surface characteristics impact Cryptosporidium transport behaviors in porous media and contributes to our capacity to evaluate the attenuation of Cryptosporidium in natural and engineered aquatic environments. [ABSTRACT FROM AUTHOR]

Abstract Kinetic mechanisms for aromatics are needed to successfully simulate the autoignition of transportation fuels using the surrogate fuel approach. An aromatic detailed kinetic mechanism that describes kinetics of C7-C11 methylated aromatics, including toluene, o-xylene, p-xylene, 1,2,4-trimethylbenzene, 1,3,5, trimethylbenzene and α−methylnaphthalene has been developed in the current study. The kinetic mechanism was built hierarchically using similar set of reaction pathways and reaction rate rules. In the mechanism developed, special emphasis is put on describing the detailed low-temperature ignition chemistry of o-xylene and 1,2,4-trimethylbenzene and, to our knowledge, this is the first attempt to do so in a detailed kinetic mechanism. In addition to kinetic modeling, new experimental data were acquired for toluene, o-xylene, and 1,2,4-trimethylbenzene using a rapid compression machine at low-to-intermediate temperatures and engine relevant pressures. In addition, the mechanism has been compared against data sets from the literature covering ignition delay times, flame speeds, and speciation profiles measured in a jet-stirred reactor and flow reactor. Good agreement is observed between the mechanism predictions and the experimental data. Kinetic analysis demonstrated the importance of including the low temperature chemistry of the benzylperoxy radicals to accurately capture the ignition propensity of o-xylene and 1,2,4-trimethylbenzene at low-to-intermediate temperatures and high pressures. The kinetic mechanism developed in the current study can be used for surrogate modeling of gasoline, jet and diesel fuels. [ABSTRACT FROM AUTHOR]

An efficient indicator group should fulfill operational and performance-related criteria, including reasonable taxonomic knowledge, costs, response to environmental changes and strong proxy-capacity for biodiversity groups. However, in the real world many trade-offs are involved in the selection of an indicator group, and a single group rarely satisfies all criteria. We investigated cross-taxon congruence of assemblage composition patterns using both quantitative and qualitative data between adult dragonflies and aquatic insects (midges, Ephemeroptera-Plecoptera-Trichoptera (EPT), beetles and entire aquatic insects assemblage). Also, we tested whether environmental and spatial variables were important drivers for cross-taxon congruence. Finally, we developed a set of guiding criteria that avoid arbitrariness in the selection of the best indicator group. We sampled adult dragonflies and aquatic insects in 41 streams and rivers along a riparian vegetation loss gradient in a Neotropical riverine network. We used Procrustes analyses to verify surrogacy between groups and the association of each group with environmental and spatial predictors. The criteria used involves both operational and performance aspects to select an indicator group. Our results showed that adult dragonflies were weakly congruent with the entire aquatic insects assemblage and aquatic insect subgroups were moderate (beetles) to strongly (EPT and midges) congruent with the entire assemblage. Comparisons between EPT, midges and beetles were also weakly congruent, with the exception of midges-EPT. The association between assemblage patterns and overall environmental predictors was significant for all groups, while with spatial patterns, only midges and entire assemblage showed significant results. Numerical resolution slightly improved the congruence results. Incidence data could be used instead of abundance, due to higher congruence values compared to abundance data. Based on cost-benefit, EPT was selected as the best indicator group for monitoring the effects of riparian vegetation loss on aquatic biodiversity, and its use could be viable in biomonitoring programs. [ABSTRACT FROM AUTHOR]

The Common Cuckoo Cuculus canorus is a well known brood parasite bird species whose density is presumed to be correlated with taxonomic, functional and phylogenetic bird species richness. However, due to the complex interplay between environmental estimates and co-evolutionary processes, the power of this relationship is still debatable. Various attempts to create statistical models have not been conclusive, because multilevel interactions between Cuckoo density, environmental conditions, and host species richness measurements have not been addressed so far. Therefore, we extended the concept of the Cuckoo as an independent bird biodiversity surrogate, and instead of simply using its occurrence, we incorporated an index of its density as an additional predictor in the modelling procedure of avian biodiversity. We applied six different indices of biodiversity as bird species richness measures, i.e. the number of bird individuals, the number of host species richness, functional richness, functional evenness, functional divergence, and evolutionary distinctiveness. We generated two sets of Species Distribution Models (SDM) for each group of biodiversity measures. One set included Cuckoo density as an additional predictor, while the other did not. Having evaluated these models in the Random Forest approach, it turned out that Cuckoo density improved model performance in each case. Species density was positively associated with taxonomic diversity (total species richness and host species richness), functional richness and evolutionary distinctiveness, and at the same time it was negatively correlated with functional evenness and functional divergence of bird communities. Thus, we suggest that through co-evolution of relationships, the Cuckoo prefers habitats attractive to numerous bird species, especially phylogenetically unique host. From the applied ecology perspective, Cuckoo density can be considered as a quantitative measure of functional interaction processes in the SDM approach, leading to the identification of avian diversity surrogates. [ABSTRACT FROM AUTHOR]

Propylene oxide (PPO), a chemical fumigant, has been validated to reduce Salmonella on bulk almonds but has not been evaluated for other tree nuts. There is a need to identify nonpathogenic surrogate microorganisms whose inactivation is comparable to that of Salmonella to assure effective PPO processing parameters in different packaging configurations without introducing Salmonella into the pasteurization facility. The objective of this research was to compare the reduction of Salmonella and three potential surrogate bacterial strains, Enterococcus faecium ATCC 8459, Pediococcus acidilactici ATCC 8042, or Staphylococcus carnosus ATCC 51365, on cashews and macadamia nuts processed by using PPO. Whole cashews and macadamia nuts were coinoculated with a five-strain cocktail of Salmonella and one surrogate, dried to the original water activity of 0.44 to 0.51 before being packaged in woven polypropylene bags (2.3 kg), and shipped overnight in Styrofoam containers under ambient conditions to a commercial facility for PPO treatment. Salmonella and surrogates were recovered by vigorous shaking in phosphate buffer (1:1, m/v), serial diluted, and plated onto tryptic soy agar with an overlay of xylose lysine Tergitol 4 for Salmonella or mannitol salt agar or bile esculin azide agar for each surrogate. The mean log reductions of Salmonella and each surrogate (n = 18), within a sample and among all trials (three independent), were compared by using a matched pairs t test. Reduction in log CFU per gram of Salmonella was significantly greater than that of E. faecium on both macadamia nuts (7.3 ± 0.19 versus 6.4 ± 0.31) and cashews (5.4 ± 0.15 versus 5.1 ± 0.25) and significantly greater than P. acidilactici on both nuts (7.8 ± 0.22 versus 6.3 6 0.33 on macadamia nuts and 4.9 ± 0.22 versus 4.1 ± 0.25 on cashews). Reduction of S. carnosus exceeded that of Salmonella. E. faecium and P. acidilactici may be considered as surrogates for Salmonella on whole macadamia nuts and cashews processed by using PPO. [ABSTRACT FROM AUTHOR]

Ignition delay times were measured behind reflected shock waves under fuel lean, high pressures conditions for conventional (JP-8) and alternative jet fuels — Fischer-Tropsch (F-T), alcohol to jet (ATJ), direct sugar to hydrocarbon (DSHC), and four bio-jet — and a biodiesel-like fuel. The primary goal of this study was to investigate the effect of fuel structure on ignition delay in order to assess differences in fuel ignition delay relative to JP-8. To support this effort, the ignition characteristics of a few hydrocarbons that are proposed as jet fuel surrogate components were also investigated: n -heptane, n -dodecane, m -xylene, n -dodecane/ m -xylene blend (77%/23% by volume) and 2,2,4,6,6-pentamethylheptane ( iso -dodecane). Two single-pulse shock tubes (heated and non-heated) were used to obtain the current data set. Using argon as the diluent (93% by volume), the experimental conditions covered a pre-ignition temperature range of approximately 980–1800 K at a pressure of 16 ± 0.8 atm and an equivalence ratio of 0.5. Experimental results show negligible differences between the ignition delay times of JP-8, F-T, DSHC, biodiesel, and the four bio-jet fuels. They are very similar to those of n -heptane, n -dodecane, n -dodecane/ m -xylene blend and iso -dodecane under similar conditions. However, the ignition delay times of the ATJ were slightly longer at higher temperatures, and similar to iso -dodecane. m -Xylene reported significantly longer ignition delay times than the other fuels tested under identical conditions. Kinetic modeling results show that light branching and carbon chain length of large n -paraffins do not alter ignition delay because the predominant reactions are oxidation of C 1 -C 4 fuel fragments. They also show for the n -dodecane/ m -xylene blend that a discernable slowing of ignition delay by fuel decomposition and oxidation of m -xylene occurs at m -xylene concentrations greater than 50% (by mol.). Further testing is required to understand this behavior at stoichiometric and fuel rich conditions. In addition, an empirical correlation was obtained between the global activation energy of the measured ignition delay times for the single paraffinic species and their derived cetane numbers. This contributes to recent efforts aimed to provide relationships between pre-vaporized, homogeneous combustion properties with existing combustion indicators. [ABSTRACT FROM AUTHOR]

A study was conducted to investigate the efficacy of a sulfuric acid–sodium sulfate blend (SSS) against Escherichia coli O157:H7, non-O157 Shiga toxin–producing E. coli (STEC), Salmonella, and nonpathogenic E. coli biotype I on prerigor beef surface tissue. The suitability of using the nonpathogenic E. coli as a surrogate for in-plant validation studies was also determined by comparing the data obtained for the nonpathogenic inoculum with those for the pathogenic inocula. Prerigor beef tissue samples (10 by 10 cm) were inoculated (ca. 6 log CFU/cm2) on the adipose side in a laboratory-scale spray cabinet with multistrain mixtures of E. coli O157:H7 (5 strains), non-O157 STEC (12 strains), Salmonella (6 strains), or E. coli biotype I (5 strains). Treatment parameters evaluated were two SSS pH values (1.5 and 1.0) and two spray application pressures (13 and 22 lb/in2). Untreated inoculated beef tissue samples served as controls for initial bacterial populations. Overall, the SSS treatments lowered inoculated (6.1 to 6.4 log CFU/cm2) bacterial populations by 0.6 to 1.5 log CFU/cm2 (P < 0.05), depending on inoculum type and recovery medium. There were no main effects (P ≥ 0.05) of solution pH or spray application pressure when SSS was applied to samples inoculated with any of the tested E. coli inocula; however, solution pH did have a significant effect (P < 0.05) when SSS was applied to samples inoculated with Salmonella. Results indicated that the response of the nonpathogenic E. coli inoculum to the SSS treatments was similar (P ≥ 0.05) to that of the pathogenic inocula tested, making the E. coli biotype I strains viable surrogate organisms for in-plant validation of SSS efficacy on beef. The application of SSS at the tested parameters to prerigor beef surface tissue may be an effective intervention for controlling pathogens in a commercial beef harvest process. [ABSTRACT FROM AUTHOR]

Infrared spectroscopy is a popular tool for fuel characterization. This study sheds light on the non-ideal blending of typical fuel surrogate components. We measure Attenuated Total Reflection Fourier-transform Infrared (ATR-FTIR) spectra of 230 liquid blends with varying compositions of n-heptane, iso-octane, ethanol, toluene, methyl-cyclohexane, 1-hexene, and cyclopentane. We report frequency shifts and excess absorbance for Primary Reference Fuels (PRFs) and their blends with ethanol, toluene, and multi-component mixtures. We showcase a variety of quantitative methods, starting with the simple Beer–Lambert linear fits, for the prediction of blend composition. We also provide calibration curves that account for non-linear blending effects, and use these to correct simulated spectra. Lastly, we discuss chemometric methods and their accuracy and robustness to interference and noise. Beyond concentrations, we predict functional groups, molecular weight, and branching index, which transform the mixture spectra to a unified basis. [Display omitted] • Frequency shifts and excess absorbance are reported for gasoline surrogates. • Calibration curves are given to capture blending non-linearity. • Chemometric methods are used for robust quantification. • Mixture spectra are broken down to a functional group basis. [ABSTRACT FROM AUTHOR]

Low-octane gasolines (RON ∼ 50–70 range) are prospective fuels for gasoline compression ignition (GCI) internal combustion engines. GCI technology utilizing low-octane fuels has the potential to significantly improve well-to-wheel efficiency and reduce the transportation sector's environmental footprint by offsetting diesel fuel usage in compression ignition engines. In this study, ignition delay times of two low-octane FACE (Fuels for Advanced Combustion Engines) gasolines, FACE I and FACE J, were measured in a shock tube and a rapid compression machine over a broad range of engine-relevant conditions (650–1200 K, 20 and 40 bar and ϕ = 0.5 and 1). The two gasolines are of similar octane ratings with anti-knock index, AKI = (RON + MON)/2, of ∼ 70 and sensitivity, S  = RON–MON, of ∼ 3. However, the molecular compositions of the two gasolines are notably different. Experimental ignition delay time results showed that the two gasolines exhibited similar reactivity over a wide range of test conditions. Furthermore, ignition delay times of a primary reference fuel (PRF) surrogate (n-heptane/iso-octane blend), having the same AKI as the FACE gasolines, captured the ignition behavior of these gasolines with some minor discrepancies at low temperatures ( T  < 700 K). Multi-component surrogates, formulated by matching the octane ratings and compositions of the two gasolines, emulated the autoignition behavior of gasolines from high to low temperatures. Homogeneous charge compression ignition (HCCI) engine simulations were used to show that the PRF and multi-component surrogates exhibited similar combustion phasing over a wide range of engine operating conditions. [ABSTRACT FROM AUTHOR]

Context: Patients with terminal illnesses often require surrogate decision makers. Prior research has demonstrated high surrogate stress, and that despite standards promoting substituted judgment, most patients do not want their surrogates to make pure substituted judgments for them. It is not known how best to help loved ones fulfill the surrogate role.Objectives: To test the effectiveness of an intervention to help surrogate decision makers.Methods: One hundred sixty-six patients (41% with amyotrophic lateral sclerosis and 59% with gastrointestinal cancers) and their surrogates at two university medical centers were randomized to an intensive nurse-directed discussion of the end-of-life decision control preferences of the patient (TAILORED) or a discussion of nutrition (CONTROL); 163 completed baseline interviews and underwent the intervention.Results: Twelve patients died during follow-up and 137 dyads completed the study. Post-intervention, using all available data, TAILORED patients and surrogates became more likely to endorse mutual surrogate decision making, that is, a balance of their own wishes and what the surrogate thinks best (adjusted odds compared with baseline for patients = 1.78, P = 0.04; adjusted odds for surrogates = 2.05, P = 0.03). CONTROL patients became 40% less likely to endorse mutual surrogate decision making (P = 0.08), and CONTROL surrogates did not change significantly from baseline (adjusted odds = 1.44, P = 0.28). Stress levels decreased for TAILORED surrogates (impact of events scale = 23.1 ± 14.6 baseline, 20.8 ± 15.3 f/u, P = 0.046), but not for CONTROL (P = 0.85), and post-intervention stress was lower for TAILORED than CONTROL (P = 0.04). Surrogates' confidence was uniformly high at baseline and did not change. Caregiver burden (Zarit) increased from 12.5 ± 6.5 to 14.7 ± 8.1 for TAILORED (P < 0.01), while not changing for CONTROL, yet satisfaction with involvement in decision making was higher at follow-up for TAILORED than for CONTROL (71% vs. 52%, P = 0.03).Conclusion: TAILORED patients and surrogates who completed the study adopted a more mutual decision-making style, balancing their own wishes with what the surrogate thinks would be best for them. Surrogates reported less stress and more satisfaction. Confidence was high at baseline and did not change. There was a modest increase in caregiver burden. These findings suggest that interventions like TAILORED might positively impact surrogate decision making. [ABSTRACT FROM AUTHOR]

The effects of unsaturation (including the C–C double bond's position in the alkyl chain) and the ester moiety in the fuel molecule on the morphology of soot particles in a laminar coflow diffusion flame are studied. The effects of the ester moiety are evaluated by comparing an n-decane flame with a biodiesel surrogate flame (composed of 50%/50% molar blend of n-decane and methyl octanoate). The effects of the unsaturation and the position of C–C double bond in the alkyl chain are analysed by comparing 1-decene, 5-decene and n-decane flames. Particles were collected thermophoretically on Transmission Electron Microscopy (TEM) carbon coated copper grids. TEM images are analysed to obtain parameters related to the size of the agglomerates such as radius of gyration, and morphological parameters such as fractal dimension and prefactor of the power-law relationship. The results show that the average primary particle diameter, the size of the agglomerates and the number of primary particles composing the agglomerates increase along the flame length to around two thirds of the flame length and then decrease as a consequence of oxidation becoming dominant over soot nucleation and growth. The fractal dimension of the agglomerates does not change significantly along the different pathlines of the flames. However, effects of the fuel chemical structure are clear. The lowest fractal dimensions are observed for the oxygenated fuel and the highest ones for the unsaturated fuels, with higher fractal dimension when the double bond is located at the edge of the molecule. The same trends are observed for agglomerate sizes: smallest agglomerates are observed for the oxygenated fuel and largest ones for the unsaturated fuels. This suggests that low soot-emitting fuels reduce their size as a consequence of oxidation while keeping their agglomeration skeletal structure. [ABSTRACT FROM AUTHOR]

A surrogate-assisted (SA) evolutionary algorithm for Multiobjective Optimization Problems (MOOPs) is presented as a contribution to Soft Computing (SC) in Artificial Intelligence (AI). Such algorithm is grounded on the cooperation between a “pure” evolutionary algorithm and a Kriging based algorithm featuring the Expected Hyper-Volume Improvement (EHVI) metric. Comparison with state-of-art pure and Kriging-assisted algorithms over two- and three-objective test functions have demonstrated that the proposed algorithm can achieve high performance in the approximation of the Pareto-optimal front mitigating the drawbacks of its parent algorithms. [ABSTRACT FROM AUTHOR]

Performing large scale simulation analyses using complex process-driven models can be very time consuming and incur significant computational expense. These analyses involve generating synthetic datasets and include processes such as impacts analysis (IA) and variance-based sensitivity analysis (SA). Machine learning (ML) provides a potential alternative path to reduce computational costs incurred when generating output from large simulation experiments. We assessed the accuracy and computational efficiency of three ML-based emulators (MLEs): artificial neural networks, multivariate adaptive regression splines, and random forest algorithms, to replicate the outputs of the APSIM-NextGen chickpea crop model. The MLEs were trained to predict seven outputs of the process-driven model. All the MLEs performed well (R2 > 0.95) for predicting outputs for the training data set locations but did not perform well for previously unseen test locations. These findings indicate that modellers using process-driven models can benefit from using MLEs for efficient data generation, provided suitable training data is provided. • Machine learning emulators of process-driven models produce accurate predictions. • Some emulator types produce more consistently accurate predictions than others. • Comprehensive training data is essential to ensure emulators can predict accurately. [ABSTRACT FROM AUTHOR]

A reduced reaction mechanism has been developed for modeling Reactivity Controlled Compression Ignition (RCCI) engine combustion with diesel fuel and syngas. Employing n -heptane as a single representative chemical surrogate for diesel fuel, a comprehensive mechanism was reduced such that the reaction mechanism of syngas oxidation is included as a sub-mechanism with emphasis on the interaction of oxidation reaction pathways of syngas and n -heptane. Important reaction pathways to be kept in the reduced mechanism to maintain the performance of the detailed mechanism were identified through ignition delay curve sensitivity analysis. In addition, reaction steps to which ignition delays of multi-fuel blends are sensitive were identified and the importance of predictability of co-oxidation of multi-fuels in the mechanism reduction process was demonstrated. The reduced mechanism, with 81 species and 312 reactions, was validated against experimental ignition delay times available in the literature. The reduced mechanism was also applied to simulate diesel-syngas RCCI engine combustion, employing a multi-component surrogate model to accurately model the physical properties of diesel fuel sprays. Predicted pressure and heat release rate results were compared with engine experimental data and good agreement was observed. The present reduced mechanism gave reliable performance for combustion predictions of RCCI engine operation to help further the fundamental understanding of the process occurring in reformed-fuel RCCI combustion and increase the computational efficiency of multi-dimensional computational fluid dynamics simulations. The reaction mechanism development outlined highlights the importance of considering co-oxidation in generation of reduced reaction mechanisms for applications to dual-fuel combustion. [ABSTRACT FROM AUTHOR]

[Display omitted] • Enhanced radical exposure during O 3 /PMS than during ozonation, even within the IOD phase. • O 3 /PMS more efficient than ozonation at short reaction times and high ozone concentrations. • Oxidation by PMS plays a role at prolonged reaction and low ozone concentrations. • UVA 254 and fluorescence intensities decrease similarly during ozonation and O 3 /PMS. • Surrogate-based models predicting TrOCs removal are different between ozonation and O 3 /PMS. Secondary effluent from wastewater treatment plants contains (bio)recalcitrant trace organic contaminants (TrOCs) that are discharged into the environment. Ozonation can offer a solution for TrOCs removal from effluent and has been extensively investigated with respect to reaction mechanisms, performance and control strategies in view of full-scale application. The ozone-activated peroxymonosulfate process (O 3 /PMS) is a relatively new and promising upgrade of ozonation for which research under real conditions is, however, still lacking. Therefore, this work focuses on the removal of 11 TrOCs with different ozone reactivity at environmentally relevant concentrations in effluent by using O 3 /PMS. At short reaction times, the hydroxyl radical exposure is approximately 2 times higher in O 3 /PMS than during ozonation at O 3 concentrations exceeding the instantaneous ozone demand (IOD). The radical production during O 3 /PMS is even noticeable at ozone concentrations lower than the IOD, which indicates that radical reaction pathways are more important during the IOD phase in O 3 /PMS than during ozonation. At longer reaction times, also direct PMS oxidation enhances the removal of some TrOCs at low ozone concentrations (< IOD). However, the extra TrOCs removal during O 3 /PMS is overall limited compared to ozonation, i.e. up to 24 % extra removal at 0.5 min reaction time and the highest ozone concentration (12.3 mg/L). In a second part of this research, spectral surrogate models based on UV absorbance at 254 nm (UVA 254) and fluorescence were developed for the prediction of TrOCs removal. The intensity of both surrogates decreased in a similar way as a function of the applied ozone concentration in both the ozonation and O 3 /PMS process. However, the regression parameters of the surrogate models and particularly the location of the inflection point show differences between both advanced oxidation processes. [ABSTRACT FROM AUTHOR]

Microgreens are niche salad greens which have increased in popularity among consumers in recent years. Due to similarities with sprouts and leafy greens—both attributed to numerous foodborne disease outbreaks—characterization of the food safety risks associated with microgreen production is warranted. The present study aimed to determine the fate and persistence of a human norovirus (HuNoV) surrogate, Tulane virus (TV), within a microgreen production system. Initially, the persistence of TV in two types of microgreen soil-free cultivation matrix (SFCM)—BioStrate® (biostrate) and peat—was determined. On day 0, water containing 7.6 log PFU of TV was applied to SFCM in growing trays, and the trays were maintained under microgreen growth conditions. TV persisted throughout the 10-day observation in biostrate and peat with overall reductions of 3.04 and 1.76 log plaque forming units (PFU) per tray, respectively. Subsequently, the transfer of TV to microgreen edible tissue was determined when planted on contaminated SFCM. Trays containing each type of SFCM were pre-inoculated with 7.6 log PFU of TV and equally divided into two areas. On day 0, sunflower (SF) or pea shoot (PS) seeds were planted on one-half of each tray, while the other half was left unplanted to serve as a control. The microgreens were harvested on day 10, and SFCM samples were collected from planted and unplanted areas of each tray. No TV were detected from the edible portion of either type of microgreen, yet TV were still present in the SFCM. TV concentrations were significantly lower in the root-containing planted area compared with the unplanted area for both biostrate (P = 0.0282) and peat (P = 0.0054). The mean differences of TV concentrations between unplanted and planted areas were 1.22 and 0.51 log PFU/g for biostrate and peat, respectively. In a subsequent investigation, TV transfer from day 7 inoculated SFCM to microgreens edible portion was not detected either. Overall, this study characterized the viral risk in a microgreen production system, which will help to understand the potential food safety risk related to HuNoV and to develop preventive measures. • Tulane virus persists in soilless substrates for at least 10 days. • TV Internalization within edible tissue of sunflower and pea shoot was not observed. • TV concentrations in soilless substrates were impacted by microgreen rhizosphere. [ABSTRACT FROM AUTHOR]

Dispatching rules are simple but efficient heuristics to solve multi-objective job shop scheduling problems, particularly useful to face the challenges of dynamic shop environments. A promising method to automatically evolve non-dominated rules represents multi-objective genetic programming based hyper-heuristic (MO-GP-HH). The aim of such methods is to approximate the Pareto front of non-dominated dispatching rules as good as possible in order to provide a sufficient set of efficient solutions from which the decision maker can select the most preferred one. However, one of the main drawbacks of existing approaches is the computational demanding simulation-based fitness evaluation of the evolving rules. To efficiently allocate the computational budget, surrogate models can be employed to approximate the fitness. Two possible ways, that estimate the fitness either based on a simplified problem or based on samples of fully evaluated individuals making use of machine learning techniques are investigated in this paper. Several representatives of both categories are first examined with regard to their selection accuracy and execution time. Furthermore, we developed a surrogate-assisted MO-GP-HH framework, incorporating a pre-selection task in the NSGA-II algorithm. The most promising candidates are consequently implemented in the framework. Using a dynamic job shop scenario, the two proposed algorithms are compared to the original one without using surrogates. With the aim to minimize the mean flowtime and maximum tardiness, experimental results demonstrate that the proposed algorithms outperform the former. Making use of surrogates leads to a reduction in computational costs of up to 70%. Another interesting finding shows that the enhanced ability to identify duplicates based on the phenotypic characterization of individuals is particularly helpful in increasing diversity within a population. This study illustrates the positive effect of this mechanism on the exploration of the entire Pareto front. • A MO-GP-HH framework is proposed to solve the multi-objective DJSS problem. • A surrogate-assisted fitness estimation is incorporated into the framework. • Comparison of surrogates regarding their selection accuracy and execution time. • Surrogate-assisted pre-selection significantly improved the algorithm. • Computational costs of the MO-GP-HH framework are reduced up to 70%. [ABSTRACT FROM AUTHOR]

Real jet fuels have hundreds of individual hydrocarbon species with varying physical and chemical properties. Surrogate fuels containing mixtures of a small number of components have been developed to emulate the behaviors of the parent fuels. Often surrogates are derived solely based on the gas-phase combustion behavior and thus are not constrained to match physical phenomena, such as atomization and vaporization. Thus, these fuels can subsequently exhibit different behaviors than the parent fuel they are designed to emulate, especially when introduced in a two-phase system. This work explores the ability of selected established and newly developed/proposed surrogate jet fuels to mimic the properties necessary for the two-phase conversion process, including the vaporization behavior of real fuel spray. The droplet lifetime/vaporization dynamics is measured using a single droplet levitating device (acoustic levitator). The newly developed surrogates show a satisfying emulation of the parent jet fuel's physical and chemical properties, including SMD, CN, LHV, MW, and vaporization evolution. Most notably, the binary solution consisting of n-dodecane and toluene predicted the physical and chemical properties of the parent fuel closely, with a total maximum deviation from the selected targeted fuel properties ∼12.6% compared to ∼52% of the well-established previously developed Dooley 1st surrogate. [ABSTRACT FROM AUTHOR]

This study investigated the response of two shellfish species - mussels (Mytilus edulis) and oysters (Crassostrea gigas) to microbial contamination in order to gain a better understanding of the bioaccumulation and persistence of microorganisms under controlled conditions. M. edulis and C. gigas were placed in sterile laboratory-prepared artificial seawater and initial tests were carried out to ensure both faecal indicator bacteria (FIB) and bacteriophages were below detection limits. FIB and phages were isolated, purified and dosed into experimental tanks containing the shellfish species. The GB124 phages were bioaccumulated to the highest concentration in M. edulis (1.88Log10) and C. gigas (1.27Log10) after 24h. Somatic coliphages were bioaccumulated to the highest concentration in both M. edulis (4.84log10) and C. gigas (1.73log10) after 48h. F-RNA phages were bioaccumulated to the highest concentration in M. edulis (3.51log10) after 6h but were below detection limit in C. gigas throughout the exposure period. Escherichia coli, faecal coliforms and intestinal enterococci were bioaccumulated to the highest concentrations in M. edulis (5.05log10, 5.06log10 and 3.98log10, respectively) after 48h. In C. gigas, E. coli reached a maximum concentration (5.47log10) after 6h, faecal coliforms (5.19log10) after 12h and intestinal enterococci (3.23log10) after 24h.M. edulis bioaccumulated phages to a greater extent than the faecal bacteria, and in both shellfish species, faecal bacteria persisted for longer periods over 48h than the phages. This study highlights significant variation in the levels and rate of accumulation and persistence with respect to both shellfish species and the indicators used to assess risk. The results suggest that phage-based indicators could help elucidate risks to human health associated with pathogenic organisms. [ABSTRACT FROM AUTHOR]

Objectives To describe LVAD patients' and surrogates' experiences with, and perspectives on SPIRIT-HF, an advance care planning (ACP) intervention. Background ACP is important for patients with LVAD, yet little is known about their experiences or those of their surrogates who have participated in ACP discussions. Methods We used qualitative content analysis techniques to conduct a secondary analysis of 28 interviews with patients with LVAD ( n = 14) and their surrogates ( n = 14) who had participated in an RCT pilot study of SPIRIT-HF. Results Main themes from the data include: 1) sharing their HF stories was very beneficial; 2) participating in SPIRIT-HF led to greater peace of mind for patients and surrogates; 3) “one size does not fit all” when it comes to timing of ACP discussions. Conclusions An understanding patient and surrogate perspectives may inform clinicians' approach to ACP discussions. [ABSTRACT FROM AUTHOR]

Objectives: To examine feasibility, acceptability and preliminary effects of an advance care planning (ACP) intervention, SPIRIT-HF, in LVAD patients and their surrogates. Background: LVADs may improve HF symptoms but they are not curative. Thus, ACP is needed to prepare patients and surrogates for end-of-life (EOL) decision-making. Methods: Bridge to transplant and destination therapy LVAD patient-surrogate dyads were randomized to either SPIRIT-HF or usual care. Percentages of eligible dyads who were enrolled and completed the study determined feasibility. Analysis of interviews with SPIRIT dyads determined acceptability. Group comparisons of dyad congruence, patient's decisional conflict, and surrogate's decision-making confidence determined preliminary effects. Results: Of 38 eligible dyads, 29 (76%) were enrolled, randomized, and completed the study. The 14 intervention dyads characterized SPIRIT-HF as beneficial. All dyads demonstrated improvement in outcomes. However, SPIRIT-HF dyads tended toward greater congruence on patient EOL treatment goals. Conclusions: SPIRIT-HF is feasible and acceptable. Results will inform future trials. [ABSTRACT FROM AUTHOR]

Ecological surrogacy – here defined as using a process or element (e.g., species, ecosystem, or abiotic factor) to represent another aspect of an ecological system – is a widely used concept, but many applications of the surrogate concept have been controversial. We argue that some of this controversy reflects differences among users with different goals, a distinction that can be crystalized by recognizing two basic types of surrogate. First, many ecologists and natural resource managers measure “indicator surrogates” to provide information about ecological systems. Second, and often overlooked, are “management surrogates” (e.g., umbrella species) that are primarily used to facilitate achieving management goals, especially broad goals such as “maintain biodiversity” or “increase ecosystem resilience.” We propose that distinguishing these two overarching roles for surrogacy may facilitate better communication about project goals. This is critical when evaluating the usefulness of different surrogates, especially where a potential surrogate might be useful in one role but not another. Our classification for ecological surrogacy applies to species, ecosystems, ecological processes, abiotic factors, and genetics, and thus can provide coherence across a broad range of uses. [ABSTRACT FROM AUTHOR]

The mechanism of injury for fractures to long bones has been studied for both direct ballistic loading as well as indirect. However, the majority of these studies have been conducted on both post-mortem human subjects (PMHS) and animal surrogates which have constraints in terms of storage, preparation and testing. The identification of a validated bone surrogate for use in forensic, medical and engineering testing would provide the ability to investigate ballistic loading without these constraints. Two specific bone surrogates, Sawbones and Synbone, were evaluated in comparison to PMHS for both direct and indirect ballistic loading. For the direct loading, the mean velocity to produce fracture was 121 ± 19 m/s for the PMHS, which was statistically different from the Sawbones (140 ± 7 m/s) and Synbone (146 ± 3 m/s). The average distance to fracture in the indirect loading was .70 cm for the PMHS. The Synbone had a statistically similar average distance to fracture (.61 cm, p=0.54) however the Sawbones average distance to fracture was statistically different (.41 cm, p<0.05). Fractures patterns were found to be comparable to the PMHS for tests conducted with Synbones, however the input parameters were slightly varied to produce similar results. The fractures patterns with the Sawbones were not found to be as comparable to the PMHS. An ideal bone surrogate for ballistic testing was not identified and future work is warranted. [ABSTRACT FROM AUTHOR]

Surrogates have been used as a support for conservation practices, since they are easier to assess and less time consuming than collecting species-level data. One of these surrogates is the “higher taxa approach”, i.e., the use of data with coarser taxonomic resolution than the species level, such as genus and family levels, as a surrogate for total species richness. The aim of this work was to test if higher taxa (Genera) could be used in the selection of important areas for bryophyte conservation, using three different methodological approaches: Scoring, Important Plant Areas and Complementarity-based approach. We tested these approaches in a protected area, the Peneda-Gerês National Park, one of the best studied areas in Portugal for bryophytes and one of the first areas in the country with bryophyte collections. The knowledge of bryophyte distribution in this National Park has been increasing and distribution maps and detailed species lists were recently published, so we thought it would be a good area to test if the higher taxa approach is an effective method for selecting important areas for bryophyte conservation. Our results showed that localities were ranked in a similar way using species or genera data, regardless of the methodology used. The Complementarity-based approach in comparison with other methodologies protected a higher percentage of bryophyte species. In general, the three approaches identified the same areas as important areas for bryophyte conservation. Therefore, for the studied area and independently of the approach used, genera could be used in the selection of important areas for bryophyte conservation. [ABSTRACT FROM AUTHOR]

Cellulose was cross-linked with epichlorohydrin (EP) at variable levels ( CLE-0.5 , CLE-2 and CLE-4) , where CLE-i denotes the cellulose to EP mole ratios. The cross-linked products were characterized by TGA and FT-IR spectroscopy, pH at the point of zero charge (pH pzc ), water swelling, and dye-adsorption methods employing two types of dyes [phenolphthalein (phth) and p -nitrophenol (PNP)]. The characterization methods provide evidence of cross-linking of cellulose in accordance with variations in surface area, PZC, available surface hydroxyl groups, and thermal stability when compared against pristine cellulose. The pH pzc of the sorbent materials was ∼6.5 indicating a negative surface charge occurs above pH pzc . The cross-linked polymers possess greater swelling properties relative to pristine cellulose. Detailed adsorption studies were carried out at pH 9 for cellulose and CLE-i with five types single component carboxylate anions [2-hexyldecanoic acid ( S1 ), trans -4-pentylcyclohexanecarboxylic acid ( S2 ), 2-dicyclohexylacetic acid ( S3 ), adamantane carboxylic acid ( S4 ), and cyclohexane carboxylic acid ( S5 )] at 295 K. The uptake properties of PNP with cellulose and CLE-i were also compared at pH 5 and 9, respectively. CLE-2 had the highest uptake of PNP ( Q m = 1.22 × 10 −1 mmol/g, pH 9) and S1 ( Q m = 4.27 mg/g) while cellulose and CLE-4 had the strongest binding affinity (1.43 L/mmol and 5.90 × 10 −2 L/mg), respectively. Uptake of PNP by CLE-0.5 at pH 5 ( Q m = 5.30 × 10 −2 mmol/g) was higher than uptake at pH 9 ( Q m = 3.11 × 10 −2 mmol/g). Sorption of CLE-4 with S1 , S2 and S3 showed that relative uptake of the surrogates had the following order: S3 > S2 > S1 , where S2 had the strongest binding affinity to CLE-i . CLE-2 had the highest sorption capacity towards Si in an equimolar mixture with evidence of molecular selective uptake. At pH 9, low uptake was mainly related to electrostatic repulsion between the negatively charged sorbent surface and the carboxylate head groups of Si . [ABSTRACT FROM AUTHOR]

With the increase in device variability, the performance uncertainty poses a daunting challenge to analog/mixed-signal circuit design. This situation requires a robust design approach to add large margins to the circuit and system-level specification to ensure correct operation and the overall yield. In this paper, we propose a new robust design approach by using norm metrics to quantify the robustness for both design parameters and performance uncertainty. In addition, we adopt a surrogating procedure to achieve robustness in design space and to reduce uncertainty in performance space. The end result of the proposed method is a Pareto-surface that provides the designer with trade-offs between design robustness and performance uncertainty. One advantage of this new approach is the ability to take into account the strong nonlinear relationship between performance and design parameters. Considering a set of highly nonlinear circuit performances, we demonstrate the effectiveness of this robust design framework on a fully CMOS operational amplifier circuit. [ABSTRACT FROM AUTHOR]

Given the limited funds available, spatial prioritisation is necessary to help decide when and where to undertake conservation. One method for setting local scale priorities for conservation action is the landscape species approach which aims to identify priorities based on the needs of a small number of wide ranging species with large environmental impacts. Despite being used for the past decade by conservation organisations such as Wildlife Conservation Society, the effectiveness of the approach for representing a more comprehensive range of biodiversity has never been evaluated. Here we compare conservation priorities identified using a suite of landscape species ( n = 13) against those using many alternative sets of threatened or endemic species ( n = 7–88) to assess the applicability and suitability of the landscape species approach in a biologically diverse landscape (Greater Virunga Landscape, Uganda, Rwanda, and Democratic Republic of Congo, Africa). We defined the minimum area needed to conserve each species on the basis of the species’ range size. We found that prioritising for landscape species adequately conserves only 31 (35%) species, whereas prioritising for an equal number of endemic species, threatened species, or randomly sampled species adequately conserves 74%, 69% and 42% of species, respectively. We also found that prioritising for one taxonomic group (birds or plants) alone resulted in better surrogacy performance than the Landscape Species. These results question the underlying assumption of the landscape species approach, that managing threats to Landscape Species will also manage threats to all other species, as it is applied in the Greater Virunga Landscape. [ABSTRACT FROM AUTHOR]

Physician recommendations have historically been a part of shared decision making. Recent literature has challenged the idea that physician recommendations should be part of shared decision making at the end of life, particularly the making of recommendations to surrogates of incapacitated patients. Close examination of the studies and the available data on surrogate preferences for decisional authority at the end of life, however, provide an empirical foundation for a style of shared decision making that includes a physician recommendation. Moreover, there are independent ethical reasons for arguing that physician recommendations enhance rather than detract from shared decision making. [ABSTRACT FROM AUTHOR]