Biphasic Model Research Articles

A biphasic relational approach to the evolution of human consciousness

Background/objectiveHuman consciousness is arguably unique, and its features are hard to explain. Continuous and discrete accounts of consciousness are commonly viewed as incompatible, but both have limitations. Continuous accounts cannot readily account for what appears to be unique about human consciousness; discrete accounts have a hard time explaining how human consciousness could have evolved. The present position paper shows how both continuous and discontinuously elements can be combined. MethodA biphasic model is constructed by unifying complex systems theory, the evolution of symbolic reasoning as a relational extension of human cooperation, and evolutionary science. The application of this approach to modern views of consciousness is then explored. ResultsOur analysis suggests that human consciousness may be viewed as a discontinuous event, that emerged from continuous foundations. This biphasic account contains processes that can be targeted clinically. For example, developmentally delayed children with problems in consciousness may be helped by targeting the processes the present account suggests are important at different levels of complexity. ConclusionsThis biphasic relational approach fits with the evolutionary record and with data on human cognitive development. It may be useful in guiding clinical intervention.

Anabolic–androgenic steroid abuse: psychiatric manifestations and treatment

IntroductionAnabolic-androgenic steroids (AAS) are synthetic derivatives of steroids which are frequently utilized in order to increase muscle mass and strength. Estimates of AAS abuse vary according to different studies. However, a global lifetime prevalence of 3.3% has been reported. The increasing illicit use of AAS over the years has raised serious public health concerns.ObjectivesTo report a clinical case of AAS abuse and review the psychopathology associated with AAS abuse and its treatment.MethodsThe authors report a clinical case and conducted a non-systematic review on the Pubmed database with the terms “anabolic-androgenic steroids”, “abuse” and “psychiatric manifestations”.ResultsA 25-year-old male patient with history of body dysmorphic disorder was admitted to the emergency services following severe psychomotor agitation and verbal and physical aggression towards his family members. He explained he had begun using AAS years prior in order to improve his physical appearance. Recently he had been administering AAS injections on a more regular basis and restricting his food and water intake. His sleep-wake cycle was disrupted and he began experiencing increasing anxiety and persecutory ideation. Additionally, increased aggression was reported and numerous conflicts with his family members took place in the weeks previous to his psychiatric observation. AAS abuse has been associated with psychiatric symptoms such as aggression and violence, mania and less commonly psychosis and suicidal ideation. Moreover, its prolonged abuse can lead to symptoms of dependence and withdrawal following suspension. A biphasic model of steroid dependence has been described. First there is a brief hyperadrenergic state with opoid-like withdrawal symptoms which is then followed by a prolonged period of depression and craving. During this phase symptoms such as fatigue, muscle and joint pain, insomnia, anxiety and depression may occur. There are no established guidelines for treatment. Acute care of agitation should follow a similar course as the one utilized in other forms of substance induced-agitation: firstly, the least invasive interventions should be implemented. If medication is required, haloperidol has been reported to be effective, although evidence is scarce. Benzodiazepines may be considered, although its use with AAS has not been reported. In regards to long term care, AAS discontinuation is vital in conjunction with proper management of withdrawal symptoms. If a patient presents symptoms of opioid-like withdrawal, treatment with clonidine may be initiated. The use of medically prescribed steroids has been suggested in order to alleviate withdrawal symptoms. Other treatment options such as human chorionic gonadotrophin and clomiphene have also been proposed.ConclusionsAAS abuse is a serious public health concern. Clinicians should be aware of its serious psychiatric effects and possible treatment courses.Disclosure of InterestNone Declared

A universal interface for plug-and-play assembly of stretchable devices.

Stretchable hybrid devices have enabled high-fidelity implantable1-3 and on-skin4-6 monitoring of physiological signals. These devices typically contain soft modules that match the mechanical requirements in humans7,8 and soft robots9,10, rigid modules containing Si-based microelectronics11,12 and protective encapsulation modules13,14. To make such a system mechanically compliant, the interconnects between the modules need to tolerate stress concentration that may limit their stretching and ultimately cause debonding failure15-17. Here, we report a universal interface that can reliably connect soft, rigid and encapsulation modules together to form robust and highly stretchable devices in a plug-and-play manner. The interface, consisting of interpenetrating polymer and metal nanostructures, connects modules by simply pressing without using pastes. Its formation is depicted by a biphasic network growth model. Soft-soft modules joined by this interface achieved 600% and 180% mechanical and electrical stretchability, respectively. Soft and rigid modules can also be electrically connected using the above interface. Encapsulation on soft modules with this interface is strongly adhesive with an interfacial toughness of 0.24 N mm-1. As a proof of concept, we use this interface to assemble stretchable devices for in vivo neuromodulation and on-skin electromyography, with high signal quality and mechanical resistance. We expect such a plug-and-play interface to simplify and accelerate the development of on-skin and implantable stretchable devices.

Is the fluid volume fraction equal to the water content in tendons? Insights on biphasic modeling

The mass density of highly hydrated soft tissues is generally assumed to be very close to that of the water, resulting that the fluid mass fraction (water content) being equal to the fluid volume fraction. Within this context, the present study aims to investigate whether such an assumption actually holds for tendon tissues and to what extent it may affect the constitutive characterizations based on biphasic (poroelastic) models. Once the water content was assessed by a classical drying assay, the fluid volume fraction was obtained based on an image segmentation approach. The main achieved results point out that the fluid volume fraction is ∼20% higher than the water content in the studied tendons (flexor digitorum profundus bovine tendons). Based on this, it is shown that the use of the water content instead of the fluid volume fraction may considerably bias the results drawn by biphasic modeling of tendons. Accordingly, a proper measurement of the fluid volume fraction is then required.

A numerical model for fibril remodeling in articular cartilage

BackgroundCollagen fibrils of articular cartilage have a distinct organization in mature human knee joints. It seems that a mechanobiological process drives the remodeling of newborn collagen fibrils with maturation. Therefore, the goal of the present study was to develop a collagen fibril remodeling algorithm that describes the unique collagen fibril organization in a 3D knee model. MethodA fibril-reinforced, biphasic cartilage model was used with a cuboid and a 3D human knee joint geometries. An isotropic collagen fibril distribution was assigned to the cartilage at the start of the analysis. Each fibril was rotated towards the direction that resulted in a maximum stretch at each time increment of the loading cycle. ResultsThe resulting pattern for the collagen fibrils was compared with split line patterns of porcine knee joint cartilage and also data published in the literature. Fibrils on the articular surface had a radial pattern towards the geometrical centroid of the tibial and femoral cartilage. In the tibiofemoral contact regions of superficial zone, fibrils were oriented circumferentially and randomly. In the porcine samples, the split-line patterns were similar to those obtained theoretically. Depth-wise organization of fibril network was characterized by fibrils perpendicular to the subchondral bone in the deeper layers, and fibrils parallel to the surface of cartilage in the superficial zone. ConclusionsThe maximum stretch criterion, coupled with a biphasic constitutive model, successfully predicted the collagen fibril organization observed in the articular cartilage throughout the depth and on the articular surface.

Understanding the Metabolism and Dissipation Kinetics of Flutriafol in Vegetables under Laboratory and Greenhouse Scenarios

Flutriafol is a systemic triazole fungicide that is used to control diseases in various crops. A study was developed to evaluate the metabolism and dissipation of flutriafol in two different scenarios: laboratory and greenhouse conditions. Courgette and tomato samples treated with a commercial product (IMPACT® EVO) at the manufacturer recommended dose were analyzed, and courgette samples were also treated at double dose. Ultra-high-performance liquid chromatography coupled with Q-Orbitrap mass spectrometry (UHPLC-Q-Orbitrap-MS), performing targeted and non-targeted approaches (suspect screening and unknown analysis), were used to analyze the samples. The dissipation of flutriafol was fitted to a biphasic kinetic model, with a persistence, expressed as half-life (t1/2), lower than 17 days. During suspect screening, three metabolites (triazole alanine, triazole lactic acid and triazole acetic acid) were tentatively identified. Unknown analysis led to the identification of four additional metabolites (C16H14F2N4, C16H14F2N4, C19H17F2N5O2 and C22H23F2N3O6). The results revealed that the proposed methodology is reliable for the determination of flutriafol and its metabolites in courgette and tomato, and seven metabolites could be detected at low concentration levels. The highest concentration of metabolites was found in the laboratory conditions at 34.5 µg/kg (triazole alanine). The toxicity of flutriafol metabolites was also evaluated, and some of them could be more toxic than the parent compound.

Occurrence of pharmaceutically active compounds, parabens, and their main metabolites in soils amended with sludge and compost

The presence of pharmaceuticals and personal care products (PPCPs) in the environment has aroused considerable interest in the last few years. However, the occurrence and fate of parent compounds and their metabolites and/or transformation products in soils have been scarcely evaluated to date. In this work, the dissipation kinetics of PPCPs, which are most frequently detected in the environment, and their main metabolites, is evaluated in soil amended with digested and composted sludge. The studied compounds were monitored for 60 days after digested or compost application to the soil. Several kinetic models were used to evaluate the dissipation kinetics of the processes. Parabens and their metabolites were the compounds with the fastest dissipation rates, while the antiepileptic carbamazepine and its metabolites were the poorest degraded compounds studied. Most of the compounds showed a single first-order dissipation kinetics. The application of biphasic kinetic models can improve the knowledge about the dissipation behavior of some of them. For instance, whereas compounds such as carbamazepine showed a high persistence showing a lag phase in its dissipation, resulting in an approximately constant concentration for the first days of batch experiments, others, such as sulfamethoxazole and diclofenac, followed a dissipation kinetics in two phases: a fast dissipation attributed to the amount of compound associated to the soil-water solution and a slow dissipation that could be due to the amount of the compound adsorbed onto the soil particle. For most of the compounds, the dissipation was faster in sludge-amended soil than in soil without organic amendment. This fact could be due to the influence of microbial activity and organic matter on their dissipation.

Inactivation trends of Bacillus cereus and Listeria monocytogenes grown in tryptic soy broth to the early stationary phase and subjected to ultraviolet irradiation

In the present study, the inactivation trends of Bacillus cereus and Listeria monocytogenes, grown in tryptic soy broth to the early stationary phase and subjected to ultraviolet (UV)-C irradiation, were identified and analyzed using mathematical models. The inactivation curves of B. cereus showed a tailing effect and were best fitted with the double Weibull model. In contrast, the inactivation curves of L. monocytogenes showed both shoulder and tailing characteristics and were best fitted with the biphasic shoulder model. The survival of highly resistant pathogens along with non-uniform bactericidal treatment was suggested as the reason for the tailing effect; the multi-hit nature of UV irradiation along with the DNA recovery ability of the pathogens was suggested as the reason for the shoulder effect. Moreover, the pathogens grown to the early stationary phase were more resistant than those grown to the mid-stationary phase. Therefore, a wider range of studies is needed regarding pathogens growing to the early stationary phase.

Survival of Listeria monocytogenes on organic Honeycrisp and Fuji apples during storage at 5, 12 and 22.5°C

This study aimed to evaluate the survival of Listeria monocytogenes on organic Honey Crisp ( HC ) and Fuji ( FJ ) apples during storage at various temperatures. Fresh organic HC and FJ apples (without waxing coating) obtained from local wholesale market were inoculated with a 2-strain mixer of L. monocytogenes followed by storing at 5.0 [22.9% Relative Humidity (RH)], 12.0 (37.0% RH), and 22.5 °C (50.4% RH) for 60, 35, 7 days, respectively, and periodically (day-0 to 60) analyzing microbial populations. Surviving L. monocytogenes were spread-plated on Modified-Oxford agar after 10 or 100-fold serial dilution. Data was analyzed using the mixed-model-procedure of SAS and GinaFit software. The initial populations of L. monocytogenes on HC and FJ apples were 6.23–6.89 log 10 CFU/apple for storage at 5, 12, and 22.5 °C. The pathogen survival cell counts decreased ( P < 0.05) to 2.34 to 4.05, 2.72 to 2.98, and 2.47 to 3.75 log 10 CFU/apple by the end of the storage at 5, 12, and 22.5 °C. L. monocytogenes was more vulnerable ( P < 0.05) on FJ than HC apples and at room temperature than cold storage temperatures. The inactivation parameters calculated from the Linear, Weibull, and Biphasic models generally are consistent with the pathogen survival curves with few exceptions. Results of this study filled the data gap for understanding of microbiological risks associated with postharvest practices of tree fruit production. Future studies are needed to quantify the natural wax amount on various organic apples and develop pre- and postharvest intenvention strategies for inactivation of foodborne pathogens on apples as well as other tree fruits. • L. monocytogenes decreased on apples during storage. • L. monocytogenes was more vulnerable on Fuji than Honey Cripsy apples. • Inactivation parameters fit the Linear, Weibull, and Biphasic models.

Growth Media of Escherichia coli Does Not Affect Its Survival in Soil under Static Conditions

Many studies have examined the survival of Escherichia coli and foodborne pathogens in agricultural soils. The results of these studies can be influenced by various growth conditions and growth media used when preparing cultures for an experiment. The objectives of this study were to (i) determine the growth curves of rifampin (R)-resistant E. coli in three types of growth media containing R: tryptic soy agar (TSA-R); tryptic soy broth (TSB-R); and poultry pellet extract (PPE-R) and (ii) evaluate the influence of growth media on the survival of E. coli in agricultural soil. Poultry pellet extract (PPE) was prepared by filter sterilizing a 1:10 suspension of heat-treated poultry pellets in sterile water. Generic E. coli (TVS 353) acclimated to 80 μg/mL of R was grown in TSA-R, TSB-R, and PPE-R at 3.0 to 3.5 log CFU/mL and incubated at 37°C. Growth curves were determined by quantifying E. coli populations at 0, 4, 8, 16, 24, and 32 h. Soil microcosms were inoculated with E. coli (6.0 log CFU/g) previously cultured in one of the three media types and stored at 25°C, and soil samples were quantified for E. coli on days 0, 1, 3, 7, 14, 28, and 42. Growth curves and survival models were generated by using DMFit and GInaFiT, respectively. E. coli growth rates were 0.88, 0.77, and 0.69 log CFU/mL/h in TSA-R, TSB-R, and PPE-R, respectively. E. coli populations in the stationary phase were greater for cultures grown in TSA-R (9.4 log CFU/mL) and TSB-R (9.1 log CFU/mL) compared with PPE-R (7.9 log CFU/mL). The E. coli populations in the soil remained stable up to 3 days before declining. An approximate 2 log CFU/g decline of E. coli in soil was observed for each culture type between days 3 and 7, after which E. coli populations declined more slowly from days 7 to 42. A biphasic shoulder model was used to evaluate E. coli survival in soils on the basis of growth media. Using standardized culture growth preparation may aid in determining the complex interactions of enteric pathogen survival in soils.

Inactivation of Alicyclobacillus acidoterrestris spores, single or composite Escherichia coli and native microbiota in isotonic fruit-flavoured sports drinks processed by UV-C light

Pasteurized sports drinks and other fruit-based beverages are susceptible to deterioration due to thermal processing ineffectiveness to inactivate certain spoilage microorganisms, like Alicyclobacillus acidoterrestris. This represents a major challenge for the beverage industry. The goals of this study were to: i) investigate the UV-C inactivation (annular thin film unit, actinometrical delivered fluence: 795–1270 mJ/cm2, 10–15 min, 20 °C, 1.8 L/h, Reh = 391–1067, recirculation mode operation) and the evolution during refrigerated storage of A. acidoterrestris ATCC 49025 spores and single or composite Escherichia coli ATCC 25922 in isotonic sports drinks (ISDs) made from orange (orange-ISD, UVT% = 81) or orange-banana-mango-kiwi-strawberry-lemon juices (multi-fruit-ISD, UVT% = 91), compared to a turbid orange-tangerine juice (OT juice, UVT% = 40); ii) assess the effect of pH, °Brix, A254nm, turbidity, colour and particle size of the ISDs and juice on microbial inactivation, iii) evaluate the evolution of native microbiota during cold storage, iv) investigate the Coroller, biphasic, Weibull, and Weibull-plus-tail models' ability to describe microbial inactivation and v) measure 5-hydroxymethylfurfural (HMF) formation. The modified biodosimetry method was used to calculate the germicidal UV-C fluences. Heat pasteurization (T-coil, 80 °C/6 min) was evaluated as the control treatment. UV-C was highly effective at inactivating E. coli as 4.1–5.1 and 4.5–5.6 log reductions were determined in the multi-fruit-ISD and orange-ISD, respectively, barely impacted by the background microbiota. No significant differences were recorded for the inactivation of E. coli in the UV-C and T-coil systems. Whereas, a significantly higher inactivation of A. acidoterrestris spores was achieved by UV-C (3.7–4.0 log reductions), compared to the negligible one achieved by the thermal treatment. Even though E. coli inactivation curves were similar in shape, UV-C was less effective when a cocktail of other E. coli strains was present. In comparison to the OT juice, the ISDs' inactivation kinetics were markedly different in shape, with a rapid decrease in population during the first minutes of treatment. The germicidal fluence (Hd biod) corresponding to A. acidoterrestris (19.1 mJ/cm2) was selected as it was higher than the one obtained for E. coli (11.0 mJ/cm2). UV-C induced 2.8- or 1.3 and 2.3- or 0.8 log-reductions of total aerobes or moulds and yeasts in the multi-fruit-ISD and orange-ISD, respectively. Compared to the other models, the Coroller and biphasic models showed a better fit and more accurate parameter estimates. UV-C-induced HMF production was not significant in the ISDs. The current study found that the UV-C treatment was more effective than typical heat pasteurization for inactivating A. acidoterrestris spores in isotonic drinks, following a similar trend for E. coli and native microbiota.

Kinetic characterization of SPR-based biomarker assays enables quality control, calibration free measurements and robust optimization for clinical application

ABSTRACT: Biomarker measurements are essential for the early diagnosis of complex diseases. However, many current biomarker assays lack sensitivity and multiplexing capacity, work in a narrow detection range and importantly lack real time quality control opportunities, which hampers clinical translation. In this paper, we demonstrate a toolbox to kinetically characterize a biomarker measurement assay using Surface Plasmon Resonance imaging (SPRi) with ample opportunities for real time quality control by exploiting quantitative descriptions of the various biomolecular interactions. We show an accurate prediction of SPRi measurements at both low and high concentrations of various analytes with deviations <5% between actual measurements and predicted measurement. The biphasic binding sites model was accurate for fitting the experimental curves and enables optimal detection of heterophilic antibodies, cross-reactivity, spotting irregularities and/or other confounders. The toolbox can also be used to create a (simulated) calibration curve, enabling calibration-free measurements with good recovery, it allows for easy assay optimizations, and could help bridge the gap to bring new biomarker assays to the clinic.

Carbohydrate-based block copolymer nanoparticles: Novel nanocarrier for delivery of chlorine-aluminum phthalocyanine for use in photodynamic therapy

The development of third-generation photosensitizers for use in photodynamic therapy (PDT) is one of the most promising directions in current cancer therapy. Nanoparticles based on the block copolymer maltoheptaose-b-poly (methyl methacrylate) (MH-b-PMMA) containing the photosensitizer chlorine-aluminum phthalocyanine (ClAlPc) were developed for application in PDT. The MH-b-PMMA@ClAlPc nanoparticles showed a hydrodynamic radius of 41 nm, low polydispersity index, negative zeta potential, high encapsulation efficiency, and optimal stability. Furthermore, MH-b-PMMA@ClAlPc nanoparticles were able to generate cytotoxic singlet oxygen (1O2), showing singlet oxygen quantum yields (ΦΔ) values close to free ClAlPc. The drug release profile from MH-b-PMMA@ClAlPc was described by a biphasic model, consisting of fast release at early time, followed by a sustained release profile. The nanoparticles were mainly located in the intestinal surrounding cells and did not induce lethality to Caenorhabditis elegans at low concentrations. Our findings highlight that glyconanoparticles have potential to be employed as novel nanocarriers for hydrophobic photosensitizers in PDT.

Numerical investigation of the couplings between strain localisation processes and gas migrations in clay materials

Deep geological repository is the preferred solution in many countries to manage radioactive wastes, such as in France where the Callovo-Oxfordian (COx) claystone is the candidate host rock. In such clay rock formation, the drilling of storage gallery creates an Excavation Damaged Zone (EDZ) with altered flow properties in the short term, while corrosion processes release large amounts of gas in the long term. Assessing the evolution of gas pressures in the near-field and predicting the effect of the EDZ on gas transport remains a major issue. This paper presents a second gradient two-phase flow hydro-mechanical (H2M) model tackling the multi-physics couplings related to gas transfers and fractures development. The EDZ is reproduced by shear strain localisation bands using a microstructure enriched model with a second gradient approach. The gas migration is captured by a biphasic fluid transfer model. The impact of fracturing on the flow properties is addressed by relating the permeability and the water retention curve to mechanical strains. Using this tool, numerical modelling of a drift in the COx claystone is performed with the aim of emphasising the influence of the HM couplings on gas migrations at nuclear waste disposal scale.

Biphasic change in retinal nerve fibre layer thickness from 30 to 60 weeks postmenstrual age in preterm infants

Background/AimsThe optic nerve development during the critical postnatal weeks of preterm infants is unclear. We aimed to investigate the change of retinal nerve fibre layer (RNFL) in preterm infants.MethodsWe used...

Heterotropic roles of divalent cations in the establishment of allostery and affinity maturation of integrin αXβ2.

SUMMARYAllosteric activation and silencing of leukocyte β2-integrins transpire through cation-dependent structural changes, which mediate integrin biosynthesis and recycling, and are essential to designing leukocyte-specific drugs. Stepwise addition of Mg2+ reveals two mutually coupled events for the αXβ2 ligand-binding domain—the αX I-domain—corresponding to allostery establishment and affinity maturation. Electrostatic alterations in the Mg2+-binding site establish long-range couplings, leading to both pH− and Mg2+-occupancy-dependent biphasic stability change in the αX I-domain fold. The ligand-binding sensorgrams show composite affinity events for the αX I-domain accounting for the multiplicity of the αX I-domain conformational states existing in the solution. On cell surfaces, increasing Mg2+ concentration enhanced adhesiveness of αXβ2. This work highlights how intrinsically flexible pH− and cation-sensitive architecture endows a unique dynamic continuum to the αI-domain structure on the intact integrin, thereby revealing the importance of allostery establishment and affinity maturation in both extracellular and intracellular integrin events.

Growth and Metabolism of Lacticaseibacillus casei and Lactobacillus kefiri Isolated from Qymyz, a Traditional Fermented Central Asian Beverage

The growth characteristics of two strains of lactic acid bacteria (LAB), Lacticaseibacillus casei and Lactobacillus kefiri, isolated from qymyz, a traditional fermented mare milk beverage, were studied and modeled, including the effect of different carbohydrates, pH, and temperature. Along with population, substrates, and metabolites, lactic acid and ethanol were monitored by HPLC. Growth parameters were obtained from mono- and biphasic logistic growth models that fit the population evolution of L. casei and L. kefiri, respectively. The effect of temperature and pH on the growth rate was represented with the gamma concept model, while the effect of the limiting substrate was evaluated according to the Monod equation. Lastly, a simplified Luedeking and Piret equation was used to represent metabolite production. The optimum values of pH and temperature were 6.69 ± 0.20, 38.63 ± 0.32 °C, 5.93 ± 0.08, and 33.15 ± 0.53 °C, with growth rate values of 0.66 ± 0.01 h−1 and 0.29 ± 0.01 h−1 for L. casei and L. kefiri, respectively. L. casei had a homofermentative pathway, while L. kefiri was heterofermentative, with an ethanol production rate of 2.90 × 10−9 mg·CFU−1. The Monod model showed that L. casei had the lowest Ks value for lactose, while for L. kefiri, it was the highest among milk carbohydrates. These results show that the population of the two LAB strains and therefore the concentrations of acid and ethanol can be controlled by the fermentation conditions and that our model can help to significantly improve the production of qymyz.

Heat treatment design for the valorization of sheep cheese whey in artisanal production

We evaluated the thermal death (62-85 ºC) of the native microbial load in sheep cheese whey (SCW), aiming to allow its use as an ingredient in smallholdings. The results showed a microbiota with mixed thermal resistance and its inactivation kinetic was fitted to a biphasic first-order kinetic model. D-values were 60.8-1.2 min at 62-70 °C (sensitive population) and 35.4-14.1 min at 70-75 ºC (resistant population). In addition, a thermoduric population (~1 log CFU/mL) was not inactivated up to 85 ºC/ 30 min. We selected three binomials (68, 75, and 80 ºC for 20, 6, and 1 min, respectively) to study the microbial growth and the physical and physicochemical changes of SCW during storage (7 ºC/ 21 days). The results demonstrated that a binomial temperature of 75 °C/ 6 min was the best option for SCW stabilization, guaranteeing acceptable microbial counts up to 14 days of storage and preserving its physical and physicochemical characteristics. These results are fundamental to guide the processing conditions of this by-product in smallholdings and can be directly applied by researchers and sheep cheese producers.

Modeling the Individual Growth of the Bonnethead Shark Sphyrna tiburo of the Western Gulf of Mexico Using the Multimodel Approach

To describe the growth pattern of the bonnethead shark (Sphyrna tiburo) in the Gulf of Mexico, a von Bertalanffy (VB) model has been automatically fit, which indicated a single−phase continuous growth without oscillations, though this would generate biases if this hypothesis is not confirmed. The objective of this research was to describe the growth pattern of S. tiburo under a multimodel approach based on information theory and contrasting single−phase models (VB, Gompertz, logistic models, and variants) and biphasic models (Soriano model and variants). The VB model was not supported. The Soriano model, with the variant in growth rate (k) and including length at birth (L0), was selected with 100% supporting evidence. The hypothesis of the two−phase growth of S. tiburo with an increase in k, more than L∞, fitted to L0, is confirmed, and a correspondence was identified between growth−phase change sizes and the sizes reported in the literature for change in the juvenile–adult stages in females and for onset of reproductive maturity in males and both sexes.

Modelling of inactivation kinetics of Escherichia coli and Listeria monocytogenes on grass carp treated by combining ultrasound with plasma functionalized buffer

Linear (first-order) and non-linear (Weibull, biphasic, and log-logistic) models were evaluated for predicting the inactivation kinetics of Escherichia coli and Listeria monocytogenes on grass carp treated by a novel technique (UPFB) combining ultrasound (US) with plasma functionalized buffer (PFB). Results showed that UPFB was more effective for inactivating bacteria when compared with individual applications of US or PFB with reductions of 3.92 and 3.70 log CFU/g for Escherichia coli and Listeria monocytogenes, respectively. Compared with the linear model, the three non-linear models presented comparable performances and were more suitable for describing the inactivation kinetics with superior adj-R2 (0.962–0.999), accuracies (0.970–1.006) and bias factors (0.995–1.031), and by assessing the strengths of evidence, weights of evidence and evidence ratios for the models, the biphasic model was identified as the best fit model. The current study provided new insights into the effective evaluation of decontamination methods.