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Zebrafish maintain a remarkable ability to regenerate their neural retina following rapid and extensive loss of retinal neurons. This is mediated by Müller glial cells (MG), which re-enter the cell cycle to produce amplifying progenitor cells that eventually differentiate into the lost retinal neurons. For example, exposing adult albino zebrafish to intense light destroys large numbers of rod and cone photoreceptors, which are then restored by MG-mediated regeneration. Here, we describe an updated method for performing these acute phototoxic lesions to adult zebrafish retinas. Next, we contrast this method to a chronic, low light lesion model that results in a more muted and sustained damage to photoreceptors and does not trigger a MG-mediated regeneration response. Thus, these two methods can be used to compare and contrast the genetic and morphological changes associated with acute and chronic methods of photoreceptor degeneration.

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[This corrects the article DOI: 10.1016/j.rpth.2024.102432.].

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Importance: Mental health disorders are prevalent yet undertreated health conditions in the US. Given perceptions about the potential effect of cannabis on individuals with mental health disorders, there is a need to understand the association of cannabis laws with psychotropic use. Objective: To investigate the association of medical and recreational cannabis laws and dispensary openings with the dispensing of psychotropic medications used to treat mental health disorders in the US. Design, Setting, and Participants: This cross-sectional study of 10 013 948 commercially insured patients used a synthetic control method to examine the association of cannabis policies with prescribing. Data on all patients dispensed prescriptions for each of the 5 classes of psychotropic medications from January 1, 2007, to December 31, 2020, were extracted from Optum's deidentified Clinformatics Data Mart Database. Statistical analysis was performed from September 2022 to November 2023. Exposures: The 4 exposure variables measured were whether medical or recreational cannabis laws were in effect and whether medical or recreational cannabis dispensaries were open in each state and calendar quarter. Main Outcome and Measures: One measure of the extensive margins of dispensing and 2 measures of the intensive margins of dispensing were constructed for 5 medication classes (benzodiazepines, antidepressants, antipsychotics, barbiturates, and sleep medications). Results: The primary sample (the benzodiazepine sample) included 3 848 721 patients (mean [SD] age, 46.1 [11.4] years; 65.4% women; 53.7% aged 35-54 years). Medical cannabis laws were associated with a 12.4% reduction in the benzodiazepine fill rate (average treatment effect on the treated [ATT], -27.4; 95% CI, -14.7 to 12.0; P = .001), recreational cannabis laws were associated with a 15.2% reduction in the fill rate (ATT, -32.5; 95% CI, -24.4 to 20.1; P = .02), and medical cannabis laws were associated with a 1.3% reduction in the mean number of benzodiazepine fills per patient (ATT, -0.02; 95% CI, -0.02 to 0.02; P = .04). Medical dispensaries were associated with a 3.9% reduction in mean days' supply per benzodiazepine fill (ATT, -1.7; 95% CI, -0.8 to 0.6; P = .001), while recreational dispensaries were associated with a 6.2% reduction (ATT, -2.4; 95% CI, -1.0 to 0.9; P < .001). Medical cannabis laws were associated with a 3.8% increase in antidepressant fills (ATT, 27.2; 95% CI, -33.5 to 26.9; P = .048), and medical dispensaries were associated with an 8.8% increase (ATT, 50.7; 95% CI, -32.3 to 28.4; P = .004). The mean number of antipsychotic medication fills per patient increased by 2.5% (ATT, 0.06; 95% CI, -0.04 to 0.05; P = .02) after medical cannabis laws and by 2.5% (ATT, 0.06; 95% CI, -0.04 to 0.04; P = .02) after medical dispensary openings. Findings for the other drug classes showed substantial heterogeneity by state and direction of association. Conclusions and Relevance: This cross-sectional study of commercially insured patients suggests that there may have been meaningful heterogeneous associations between cannabis policy and state and between cannabis policy and drug class (eg, decreases in dispensing of benzodiazepines but increases in dispensing of antidepressants and antipsychotics). This finding suggests additional clinical research is needed to understand the association between cannabis use and mental health. The results have implications for patient substance use and mental health-related outcomes.

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Cardiac troponin I (cTnI) is a cardiac-specific biomarker, used for the detection of myocardial injury. While rabbits develop naturally occurring cardiovascular disease, they are also an animal model for human disease; thus, rapid detection of cTnI has implications for both veterinary and human medicine. The objective of this study was to validate and establish a reference interval for a point-of-care (POC) cTnI assay in New Zealand White rabbits. In the first portion of the study, rabbit cardiac and skeletal muscle tissues were used to create homogenates, serially diluted with saline or rabbit whole blood, and run by repeated analysis on the POC assay. In the second portion of the study, a reference interval of peripheral whole blood cTnI was determined by robust methods from 49 New Zealand White rabbits. The least diluted cardiac muscle homogenates produced detectable cTnI (mean 23.12 ± 3.557 ng/mL), while skeletal muscle homogenates produced low to undetectable cTnI. The CV ranged from 0.00% to 32.51% for cTnI of diluted cardiac muscle homogenates. Rabbit cardiac homogenate diluted in blood had a linear relationship to cTnI concentration (Y = 0.2254 × X + 0.5396, R² = 0.975). The reference interval for cTnI in this population was less than 0.04 ng/mL. This POC assay may be useful when rapid detection of cTnI is needed and differentiation between normal and elevated values is required. Given the high CV, this assay may not be appropriate for cases that require high sensitivity or detection of low concentrations of cTnI.

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Until recent events, the Antarctic was the only major geographical region in which high pathogenicity avian influenza virus (HPAIV) had never previously been detected. Here we report on the detection of clade 2.3.4.4b H5N1 HPAIV in the Antarctic and sub-Antarctic regions of South Georgia and the Falkland Islands, respectively. We initially detected H5N1 HPAIV in samples collected from brown skuas at Bird Island, South Georgia on 8th October 2023. Since this detection, mortalities were observed in several avian and mammalian species at multiple sites across South Georgia. Subsequent testing confirmed H5N1 HPAIV across several sampling locations in multiple avian species and two seal species. Simultaneously, we also confirmed H5N1 HPAIV in southern fulmar and black-browed albatross in the Falkland Islands. Genetic assessment of the virus indicates spread from South America, likely through movement of migratory birds. Critically, genetic assessment of sequences from mammalian species demonstrates no increased risk to human populations above that observed in other instances of mammalian infections globally. Here we describe the detection, species impact and genetic composition of the virus and propose both introductory routes and potential long-term impact on avian and mammalian species across the Antarctic region. We also speculate on the threat to specific populations following recent reports in the area.

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Non-invasive brain imaging has played a critical role in establishing our understanding of the neural properties that contribute to the emergence of psychiatric disorders. However, characterizing core neurobiological mechanisms of psychiatric symptomatology requires greater structural, functional, and neurochemical specificity than is typically obtainable with standard field strength MRI acquisitions (e.g., 3T). Ultra-high field (UHF) imaging at 7 Tesla (7T) provides the opportunity to identify neurobiological systems that confer risk, determine etiology, and characterize disease progression and treatment outcomes of major mental illnesses. Increases in scanner availability, regulatory approval, and sequence availability have made the application of UHF to clinical cohorts more feasible than ever before, yet the application of UHF approaches to the study of mental health remains nascent. In this technical review, we describe core neuroimaging methodologies which benefit from UHF acquisition, including high resolution structural and functional imaging, single (1H) and multi-nuclear (e.g., 31P) MR spectroscopy, and quantitative MR techniques for assessing brain tissue iron and myelin. We discuss advantages provided by 7T MRI, including higher signal- and contrast-to-noise ratio, enhanced spatial resolution, increased test-retest reliability, and molecular and neurochemical specificity, and how these have begun to uncover mechanisms of psychiatric disorders. Finally, we consider current limitations of UHF in its application to clinical cohorts, and point to ongoing work that aims to overcome technical hurdles through the continued development of UHF hardware, software, and protocols.

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BACKGROUND: Neonates undergoing cardiac surgery require fibrinogen replacement to restore hemostasis after cardiopulmonary bypass (CPB). Cryoprecipitate is often the first-line treatment, but recent studies demonstrate that fibrinogen concentrate (RiaSTAP; CSL Behring) may be acceptable in this population. This investigator-initiated, randomized trial compares cryoprecipitate to fibrinogen concentrate in neonates undergoing cardiac surgery (ClinicalTrials.gov NCT03932240). The primary end point was the percent change in ex vivo clot degradation from baseline at 24 hours after surgery between groups. Secondary outcomes included intraoperative blood transfusions, coagulation factor levels, and adverse events. METHODS: Neonates were randomized to receive cryoprecipitate (control group) or fibrinogen concentrate (study group) as part of a post-CPB transfusion algorithm. Blood samples were drawn at 4 time points: presurgery (T1), after treatment (T2), arrival to the intensive care unit (ICU) (T3), and 24 hours postsurgery (T4). Using the mixed-effect models, we analyzed the percent change in ex vivo clot degradation from a patient's presurgery baseline at each time point. Intraoperative blood product transfusions, coagulation factor levels, perioperative laboratory values, and adverse events were collected. RESULTS: Thirty-six neonates were enrolled (intent to treat [ITT]). Thirteen patients in the control group and seventeen patients in the study group completed the study per protocol (PP). After normalizing to the patient's own baseline (T1), no significant differences were observed in clot degradation at T2 or T3. At T4, patients in the study group had greater degradation when compared to those in the control group (826.5%, 95% confidence interval [CI], 291.1-1361.9 vs -545.9%, 95% CI, -1081.3 to -10.4; P < .001). Study group patients received significantly less median post-CPB transfusions than control group patients (ITT, 27.2 mL/kg [19.0-36.9] vs 41.6 [29.2-52.4]; P = .043; PP 26.7 mL/kg [18.8-32.2] vs 41.2 mL/kg [29.0-51.4]; P < .001). No differences were observed in bleeding or thrombotic events. CONCLUSIONS: Neonates who received fibrinogen concentrate, as compared to cryoprecipitate, have similar perioperative ex vivo clot degradation with faster degradation at 24 hours postsurgery, less post-CPB blood transfusions, and no increased bleeding or thrombotic complications. Our findings suggest that fibrinogen concentrate adequately restores hemostasis and reduces transfusions in neonates after CPB without increased bleeding or thrombosis risk.

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ABSTRACT: Silicosis typically has been classified as a chronic disease that develops after at least 10 years of exposure to silica dust, and often is associated with miners and stone workers. As industries have changed over time, other types of workers (including those in artificial stonework, jewelry polishing, and denim production) have become exposed to high levels of silica, leading to the development of acute and accelerated silicosis. Acute silicosis can develop in as little as a few months, and accelerated silicosis can develop in as little as 2 years. No cure exists for any form of silicosis, and lung transplantation is the only lifesaving treatment. Primary care clinicians must understand when patients are at risk for developing silicosis and not assume that a short time of exposure precludes the development of silicosis.

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Proline is widely known as the only proteogenic amino acid with a secondary amine. In addition to its crucial role in protein structure, the secondary amino acid modulates neurotransmission and regulates the kinetics of signaling proteins. To understand the structural basis of proline import, we solved the structure of the proline transporter SIT1 in complex with the COVID-19 viral receptor ACE2 by cryo-electron microscopy. The structure of pipecolate-bound SIT1 reveals the specific sequence requirements for proline transport in the SLC6 family and how this protein excludes amino acids with extended side chains. By comparing apo and substrate-bound SIT1 states, we also identify the structural changes that link substrate release and opening of the cytoplasmic gate and provide an explanation for how a missense mutation in the transporter causes iminoglycinuria.

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In this study, we report on the preparation, characterization, and cytocompatibility of hydrogels for biomedical applications made from two different molecular weights of chitosan (CS) blended with poly(vinyl alcohol) (PVA) and chemically cross-linked with tetraethyl orthosilicate (TEOS) followed by freeze-drying. A series of CS-PVA hydrogels were synthesized with different amounts of chitosan (1%, 2%, and 3% by weight). The structure of these CS-PVA hydrogels was characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The hydrogel samples were also characterized for tensile strength, contact angle, swelling behavior, and degradation at physiological body temperature. Their physicochemical properties, biocompatibility, and cell viability when cultured with human dermal fibroblasts were assessed using alamarBlue and live/dead assays and compared to optimize their functionality. SEM analysis showed that the concentration and molecular weight of the chitosan component affected the pore size. Furthermore, the contact angle decreased with increasing chitosan content, indicating that chitosan increased its hydrophilic properties. The in vitro degradation study revealed a nonlinear time-dependent relationship between chitosan concentration or molecular weight, and the rate of degradation was affected by the pore size of the hydrogel. All of the CS-PVA hydrogels exhibited good cell proliferation, particularly with the high molecular weight chitosan samples.

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Between 2013 and 2017, the A/Anhui/1/13-lineage (H7N9) low-pathogenicity avian influenza virus (LPAIV) was epizootic in chickens in China, causing mild disease, with 616 fatal human cases. Despite poultry vaccination, H7N9 has not been eradicated. Previously, we demonstrated increased pathogenesis in turkeys infected with H7N9, correlating with the emergence of the L217Q (L226Q H3 numbering) polymorphism in the haemagglutinin (HA) protein. A Q217-containing virus also arose and is now dominant in China following vaccination. We compared infection and transmission of this Q217-containing 'turkey-adapted' (ty-ad) isolate alongside the H7N9 (L217) wild-type (wt) virus in different poultry species and investigated the zoonotic potential in the ferret model. Both wt and ty-ad viruses demonstrated similar shedding and transmission in turkeys and chickens. However, the ty-ad virus was significantly more pathogenic than the wt virus in turkeys but not in chickens, causing 100 and 33% mortality in turkeys respectively. Expanded tissue tropism was seen for the ty-ad virus in turkeys but not in chickens, yet the viral cell receptor distribution was broadly similar in the visceral organs of both species. The ty-ad virus required exogenous trypsin for in vitro replication yet had increased replication in primary avian cells. Replication was comparable in mammalian cells, and the ty-ad virus replicated successfully in ferrets. The L217Q polymorphism also affected antigenicity. Therefore, H7N9 infection in turkeys can generate novel variants with increased risk through altered pathogenicity and potential HA antigenic escape. These findings emphasize the requirement for enhanced surveillance and understanding of A/Anhui/1/13-lineage viruses and their risk to different species.

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OBJECTIVE: Understanding and quantifying biases when designing and implementing actionable approaches to increase fairness and inclusion is critical for artificial intelligence (AI) in biomedical applications. METHODS: In this Special Communication, we discuss how bias is introduced at different stages of the development and use of AI applications in biomedical sciences and health care. We describe various AI applications and their implications for fairness and inclusion in sections on 1) Bias in Data Source Landscapes, 2) Algorithmic Fairness, 3) Uncertainty in AI Predictions, 4) Explainable AI for Fairness and Equity, and 5) Sociological/Ethnographic Issues in Data and Results Representation. RESULTS: We provide recommendations to address biases when developing and using AI in clinical applications. CONCLUSION: These recommendations can be applied to informatics research and practice to foster more equitable and inclusive health care systems and research discoveries.

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Infection is a major cause of treatment-related morbidity and mortality in pediatric acute lymphoblastic leukemia (ALL). Most children with ALL who develop life-threatening bacterial infections do so during induction therapy. We describe a rare case of ALL presenting simultaneously with Streptococcus agalactiae group B Streptococcus bacteremia and meningitis in a 3-year-old girl. She received appropriate antimicrobial therapy and a 2-drug early induction regimen consisting of vincristine and dexamethasone, leading to slow neurologic recovery and a favorable initial response to anti-neoplastic therapy as evidenced by minimal residual disease of 1.12% on day 15 of induction.

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BACKGROUND: Borderline Personality Disorder (BPD) is associated with heightened impulsivity, evidenced by increased substance abuse, self-harm and suicide attempts. Addressing impulsivity in individuals with BPD is a therapeutic objective; but its underlying neural basis in this clinical population remains unclear, partly due to its frequent co-morbidity with attention-deficit/hyperactivity disorder (ADHD). METHODS: We employed a response inhibition paradigm - the interleaved pro-/anti-saccade task (IPAST) - among adolescents diagnosed with BPD with and without comorbid ADHD (N=25 and N=24, respectively) during concomitant video-based eye-tracking. We quantified various eye movement response parameters reflective of impulsive action during the task, including delay to fixation acquisition, fixation breaks, anticipatory saccades, and direction errors with express saccade (Saccade Reaction Time [SRT]: 90-140 ms) and regular saccade latencies (SRT > 140 ms). RESULTS: Individuals with BPD exhibited deficient response preparation, exampled by reduced visual fixation on task cues and greater variability of saccade responses (i.e., SRT and peak velocity). The ADHD/BPD group shared these traits, as well as produced an increased frequency of anticipatory responses and direction errors with express saccade latencies and reduced error correction. CONCLUSIONS: Saccadic deficits in BPD and ADHD/BPD stem not from an inability to execute anti-saccades, but rather from an inadequate preparation for the upcoming task set. These distinctions may arise due to abnormal signaling in cortical areas like the frontal eye fields, posterior parietal cortex, and anterior cingulate cortex. Understanding these mechanisms could provide insights into targeted interventions focusing on task set preparation to manage response inhibition deficits in BPD and ADHD/BPD.

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Introduction: Optimizing the performance of emergency department (ED) teams impacts patient care, but the utility of current, team-based performance assessment tools to comprehensively measure this impact is underexplored. In this study we aimed to 1) evaluate ED team performance using current team-based assessment tools during an interprofessional in situ simulation and 2) identify characteristics of effective ED teams. Methods: This mixed-methods study employed case study methodology based on a constructivist paradigm. Sixty-three eligible nurses, technicians, pharmacists, and postgraduate year 2-4 emergency medicine residents at a tertiary academic ED participated in a 10-minute in situ simulation of a critically ill patient. Participants self-rated performance using the Team Performance Observation Tool (TPOT) 2.0 and completed a brief demographic form. Two raters independently reviewed simulation videos and rated performance using the TPOT 2.0, Team Emergency Assessment Measure (TEAM), and Ottawa Crisis Resource Management Global Rating Scale (Ottawa GRS). Following simulations, we conducted semi-structured interviews and focus groups with in situ participants. Transcripts were analyzed using thematic analysis. Results: Eighteen team-based simulations took place between January-April 2021. Raters' scores were on the upper end of the tools for the TPOT 2.0 (R1 4.90, SD 0.17; R2 4.53, SD 0.27, IRR [inter-rater reliability] 0.47), TEAM (R1 3.89, SD 0.19; R2 3.58, SD 0.39, IRR 0.73), and Ottawa GRS (R1 6.6, SD 0.56; R2 6.2, SD 0.54, IRR 0.68). We identified six themes from our interview data: team member entrustment; interdependent energy; leadership tone; optimal communication; strategic staffing; and simulation empowering team performance. Conclusion: Current team performance assessment tools insufficiently discriminate among high performing teams in the ED. Emergency department-specific assessments that capture features of entrustability, interdependent energy, and leadership tone may offer a more comprehensive way to assess an individual's contribution to a team's performance.

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BACKGROUND: How state opioid policy environments with multiple concurrent policies affect opioid prescribing to individuals with acute pain is unknown. OBJECTIVE: To examine how prescription drug monitoring programs (PDMPs), pain management clinic regulations, initial prescription duration limits, and mandatory continued medical education affected total and high-dose prescribing. DESIGN: A county-level multiple-policy difference-in-difference event study framework. SUBJECTS: A total of 2,425,643 individuals in a large national commercial insurance deidentified claims database (aged 12-64 years) with acute pain diagnoses and opioid prescriptions from 2007 to 2019. MAIN MEASURES: The total number of acute pain opioid treatment episodes and number of episodes containing high-dose (> 90 morphine equivalent daily dosage (MEDD)) prescriptions. KEY RESULTS: Approximately 7.5% of acute pain episodes were categorized as high-dose episodes. Prescription duration limits were associated with increases in the number of total episodes; no other policy was found to have a significant impact. Beginning five quarters after implementation, counties in states with pain management clinic regulations experienced a sustained 50% relative decline in the number of episodes containing > 90 MEDD prescriptions (95 CIs: (Q5: - 0.506, - 0.144; Q12: - 1.000, - 0.290)). Mandated continuing medical education regarding the treatment of pain was associated with a 50-75% relative increase in number of high-dose episodes following the first year-and-a-half of enactment (95 CIs: (Q7: 0.351, 0.869; Q12: 0.413, 1.107)). Initial prescription duration limits were associated with an initial relative reduction of 25% in high-dose prescribing, with the effect increasing over time (95 CI: (Q12: - 0.967, - 0.335). There was no evidence that PDMPs affected high-dose opioids dispensed to individuals with acute pain. Other high-risk prescribing indicators were explored as well; no consistent policy impacts were found. CONCLUSIONS: State opioid policies may have differential effects on high-dose opioid dispensing in individuals with acute pain. Policymakers should consider effectiveness of individual policies in the presence of other opioid policies to address the ongoing opioid crisis.

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In January 2020, increased mortality was reported in a small broiler breeder flock in County Fermanagh, Northern Ireland. Gross pathological findings included coelomitis, oophoritis, salpingitis, visceral gout, splenomegaly, and renomegaly. Clinical presentation included inappetence, pronounced diarrhoea, and increased egg deformation. These signs, in combination with increased mortality, triggered a notifiable avian disease investigation. High pathogenicity avian influenza virus (HPAIV) was not suspected, as mortality levels and clinical signs were not consistent with HPAIV. Laboratory investigation demonstrated the causative agent to be a low-pathogenicity avian influenza virus (LPAIV), subtype H6N1, resulting in an outbreak that affected 15 premises in Northern Ireland. The H6N1 virus was also associated with infection on 13 premises in the Republic of Ireland and six in Great Britain. The close genetic relationship between the viruses in Ireland and Northern Ireland suggested a direct causal link whereas those in Great Britain were associated with exposure to a common ancestral virus. Overall, this rapidly spreading outbreak required the culling of over 2 million birds across the United Kingdom and the Republic of Ireland to stamp out the incursion. This report demonstrates the importance of investigating LPAIV outbreaks promptly, given their substantial economic impacts.

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Supplemental feeding can increase the overall health of animals but also can have variable effects on how animals defend themselves against parasites. However, the spatiotemporal effects of food supplementation on host-parasite interactions remain poorly understood, likely because large-scale, coordinated efforts to investigate them are difficult. Here, we introduce the Nest Parasite Community Science Project, which is a community-based science project that coordinates studies with bird nest box 'stewards' from the public and scientific community. This project was established to understand broad ecological patterns between hosts and their parasites. The goal of this study was to determine the effect of food supplementation on eastern bluebirds (Sialia sialis) and their nest parasite community across the geographic range of the bluebirds from 2018 to 2021. We received 674 nests from 69 stewards in 26 states in the eastern United States. Nest box stewards reported whether or not they provided mealworms or suet near nesting bluebirds, then they followed the nesting success of the birds (number of eggs laid and hatched, proportion that hatched, number and proportion of nestlings that successfully fledged). We then identified and quantified parasites in the nests. Overall, we found that food supplementation increased fledging success. The most common nest parasite taxon was the parasitic blow fly (Protocalliphora sialia), but a few nests contained fleas (Ceratophyllus idius, C. gallinae and Orchopeas leucopus) and mites (Dermanyssus spp. and Ornithonyssus spp.). Blow flies were primarily found at northern latitudes, where food supplementation affected blow fly prevalence. However, the direction of this effect varied substantially in direction and magnitude across years. More stewards fed bluebirds at southern latitudes than at northern latitudes, which contradicts the findings of other community-based science projects. Overall, food supplementation of birds was associated with increased host fitness but did not appear to play a consistent role in defence against these parasites across all years. Our study demonstrates the importance of coordinated studies across years and locations to understand the effects of environmental heterogeneity, including human-based food supplementation, on host-parasite dynamics.

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High pathogenicity avian influenza viruses (HPAIVs) cause high morbidity and mortality in poultry species. HPAIV prevalence means high numbers of infected wild birds could lead to spill over events for farmed poultry. How these pathogens survive in the environment is important for disease maintenance and potential dissemination. We evaluated the temperature-associated survival kinetics for five clade 2.3.4.4 H5Nx HPAIVs (UK field strains between 2014 and 2021) incubated at up to three temperatures for up to ten weeks. The selected temperatures represented northern European winter (4 °C) and summer (20 °C); and a southern European summer temperature (30 °C). For each clade 2.3.4.4 HPAIV, the time in days to reduce the viral infectivity by 90% at temperature T was established (DT), showing that a lower incubation temperature prolonged virus survival (stability), where DT ranged from days to weeks. The fastest loss of viral infectivity was observed at 30 °C. Extrapolation of the graphical DT plots to the x-axis intercept provided the corresponding time to extinction for viral decay. Statistical tests of the difference between the DT values and extinction times of each clade 2.3.4.4 strain at each temperature indicated that the majority displayed different survival kinetics from the other strains at 4 °C and 20 °C.

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