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1.
J Agric Food Chem ; 72(32): 18110-18120, 2024 Aug 14.
Article in English | MEDLINE | ID: mdl-39093148

ABSTRACT

Some consumers are replacing cow's milk with plant-based milk alternatives (PBMAs). The present study aimed to characterize the lipid profiles of cow's milk (n = 60) and PBMA types (soya, oat, rice, almond, coconut, and hazelnut; n = 10 per type). Significant differences were found in the fatty acid (FA) profiles of PBMAs and milk, particularly in FA diversity (15 FAs in PBMAs vs 54 FAs in milk) and the proportion of prime FA groups. The FA profile of coconut was dominated by saturated FAs (SFA), whereas monounsaturated FAs (MUFA) or polyunsaturated FAs (PUFA) were dominant in the remaining PBMA types. Cholesterol was not detected in any PBMA type. The FA profile of milk FAs was dominated by SFA; however, different individual SFA have varying health outcomes. Additionally, milk contains some FA groups with health-promoting properties, such as methyl-branched-chain FAs (BCFA) and conjugated linoleic acid (CLA), both of which are absent in PBMAs.


Subject(s)
Fatty Acids , Milk Substitutes , Milk , Animals , Milk/chemistry , Cattle , Fatty Acids/analysis , Fatty Acids/chemistry , Milk Substitutes/chemistry , Avena/chemistry , Corylus/chemistry , Lipids/analysis , Lipids/chemistry , Oryza/chemistry , Cocos/chemistry , Prunus dulcis/chemistry , Glycine max/chemistry , Female
2.
Food Chem ; 461: 140768, 2024 Dec 15.
Article in English | MEDLINE | ID: mdl-39181051

ABSTRACT

The aim of this paper is to provide a thorough review of recent research on the effects of high pressure processing (HPP) and hyperbaric storage (HS) on lipid oxidation amounts in different food products, as well as the mechanisms of lipid oxidation during processing and storage. Globaly, highly perishable foods showed an increase in lipid oxidation when preserved by HPP. On the other hand, HS using lower pressure levels but much longer time under pressure seems to cause a higher level of secondary lipid oxidation products and a lower level of tertiary products, with HS so decreasing oxidation progress during storage. Existing studies have mainly focused on individual oxidation indicators, highlighting the need for a comprehensive analysis of primary, secondary, and tertiary oxidation products in order to fully understand the progression of oxidation. This comprehensive approach ensures a systematic assessment of lipid oxidation, leading to a clear understanding of the oxidation process.


Subject(s)
Lipids , Oxidation-Reduction , Pressure , Lipids/chemistry , Food Handling , Food Preservation/methods , Food Preservation/instrumentation
3.
Pathogens ; 13(8)2024 Jul 31.
Article in English | MEDLINE | ID: mdl-39204248

ABSTRACT

Parasitic diseases can affect animal health and welfare, and they may also constitute a danger to public health, particularly in island ecosystems. Fecal samples were collected from 205 dogs and 115 cats on the islands of São Miguel and Terceira, Azores archipelago (Portugal), using the Willis flotation technique and modified Baermann method, for further analysis. The overall prevalence of gastrointestinal parasitism in dogs was 53%, with the following results: Ancylostomatidae (hookworms) (42.44%), Trichuris vulpis (17.56%), Toxocara canis (12.68%) and Cystoisospora spp. (4.39%). In cats, the overall prevalence was also 53%, with the following results: Toxocara cati (31.3%), Ancylostomatidae (30.43%), Cystoisospora spp. (14.78%) and Trichuris sp. (0.87%). The prevalence of lungworms was 0.49% in canines and 20.87% in felines, with Angiostrongylus vasorum and Aelurostrongylus abstrusus species being detected in dogs and cats, respectively. The present survey detected a high prevalence of gastrointestinal infection, in both dogs and cats, probably because the samples came mainly from kennels and catteries and due to the peculiar climatic conditions in this insular territory, with mild temperature and high relative humidity. A considerable prevalence of aelurostrongylosis was also detected (20.87%), so it should be included in the list of differential diagnoses of diseases concerning the respiratory tract in cats of the archipelago.

4.
Sensors (Basel) ; 24(14)2024 Jul 11.
Article in English | MEDLINE | ID: mdl-39065883

ABSTRACT

Spores from the fungus Pithomyces chartarum are commonly found on Azorean pastures. When consumed by cattle along with the grass, these spores cause health issues in the cattle, resulting in animal suffering and financial losses. For approximately two years, we monitored meteorological parameters using weather stations and collected and analyzed grass samples in a laboratory to control for the presence of spores. The data confirmed a connection between meteorology and sporulation, enabling the prediction of sporulation risk. To detect the presence of spores in pastures rather than predict it, we employed field spectrometry and Sentinel-2 reflectance data to measure the spectral signatures of grass while controlling for spores. Our findings indicate that meteorological variables from the past 90 days can be used to predict sporulation, which can enhance the accuracy of a web-based alert system used by farmers to manage the risk. We did not detect significant differences in spectral signatures between grass with and without spores. These studies contribute to a deeper understanding of P. chartarum sporulation and provide actionable information for managing cattle, ultimately improving animal welfare and reducing financial losses.


Subject(s)
Remote Sensing Technology , Spores, Fungal , Animals , Cattle , Remote Sensing Technology/methods , Spores, Fungal/isolation & purification , Poaceae/microbiology , Azores , Internet of Things
5.
Einstein (Sao Paulo) ; 22: eRC0582, 2024.
Article in English | MEDLINE | ID: mdl-38958338

ABSTRACT

The focus of this case report is to technically describe a noninvasive diagnostic evaluation of bow Hunter's syndrome using a dynamic computed tomography angiography protocol and discuss its advantages. In addition, we aimed to exemplify the quality of the study by presenting images of a 3D-printed model generated to help plan the surgical treatment for the patient. The dynamic computed tomography angiography protocol consisted of a first image acquisition with the patient in the anatomic position of the head and neck. This was followed by a second acquisition with the head and neck rotated to the side that triggered the symptoms, with technical parameters similar to the first acquisition. The acquired images were used to print a 3D model to better depict the findings for the surgical team. The dynamic computed tomography angiography protocol developed in this study helped visualize the vertebrobasilar arterial anatomy, detect vertebral artery stenosis produced by head and neck rotation, depict the structure responsible for artery stenosis (e.g., bony structure or membranes), and study possible complications of the disease (e.g., posterior cerebral circulation infarction). Additionally, the 3D-printed model better illustrated the findings of stenosis, aiding in surgical planning. In conclusion, dynamic computed tomography angiography for the evaluation of bow Hunter's syndrome is a feasible noninvasive technique that can be used as an alternative to traditional diagnostic methods.


Subject(s)
Computed Tomography Angiography , Vertebrobasilar Insufficiency , Humans , Computed Tomography Angiography/methods , Vertebrobasilar Insufficiency/diagnostic imaging , Vertebrobasilar Insufficiency/surgery , Male , Vertebral Artery/diagnostic imaging , Imaging, Three-Dimensional/methods , Printing, Three-Dimensional
6.
Food Chem ; 456: 139945, 2024 Oct 30.
Article in English | MEDLINE | ID: mdl-38850604

ABSTRACT

This study investigated the potential of incorporating cardoon (Cynara cardunculus L.) blades as bioactive and dietary fiber ingredients in vegetable/fruit-based smoothies, within a zero-waste approach. The smoothie formulations were pasteurized by high-pressure (550 MPa for 3 min, HPP) and thermal (90 °C for 30 s, TP) treatments and stored at 4 °C for 50 days. Cardoon-fortified smoothies exhibited higher viscosity, darker color, increased phenolic compound levels, and greater anti-inflammatory and antioxidant activities. Furthermore, the cardoon blade ingredients contributed to a more stable dietary fiber content throughout the smoothies' shelf-life. HPP-processed smoothies did not contain sucrose, suggesting enzymatic activity that resulted in sucrose hydrolysis. All beverage formulations had low or no microbial growth within European limits. In conclusion, the fortification of smoothies with cardoon blades enhanced bioactive properties and quality attributes during their shelf-life, highlighting the potential of this plant material as a potential functional food ingredient in a circular economy context.


Subject(s)
Cynara , Pasteurization , Cynara/chemistry , Hot Temperature , Antioxidants/chemistry , Functional Food/analysis , Food Handling/instrumentation , Fruit/chemistry , Cold Temperature , Food Storage , Beverages/analysis
7.
Am Soc Clin Oncol Educ Book ; 44(3): e432102, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38870439

ABSTRACT

Quality cancer care is efficient, accessible, coordinated, and evidence-based. Recognizing the necessary key components, development of pathways and guidelines to incorporate these key domains, and finally respectful adaptation to cultural differences can ensure that cancer care globally is of the highest quality. This quality care should be judged not only on how it optimizes health outcomes for patients, but also its impact on the care providers and the global community.


Subject(s)
Medical Oncology , Neoplasms , Quality of Health Care , Humans , Delivery of Health Care/standards , Global Health , Medical Oncology/standards , Neoplasms/therapy
8.
Foods ; 13(12)2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38928774

ABSTRACT

This study aimed to evaluate hyperbaric storage at room temperature (75-200 MPa, 30 days, 18-23 °C, HS/RT) on Clostridium perfringens spores in brain-heart infusion broth (BHI-broth) at pH 4.50, 6.00, and 7.50 and coconut water (pH 5.40). Both matrices were also pasteurized by high pressure processing (600 MPa, 3 min, 17 °C, HPP) to simulate commercial pasteurization followed by HS, in comparison with refrigeration (5 °C, RF). The results showed that, at AP/RT, spores' development occurred, except at pH 4.50 in BHI-broth, while for RF, no changes occurred along storage. Under HS, at pH 4.50, neither spore development nor inactivation occurred, while at pH 6.00/7.50, inactivation occurred (≈2.0 and 1.0 logs at 200 MPa, respectively). Coconut water at AP/RT faced an increase of 1.6 logs of C. perfringens spores after 15 days, while for RF, no spore development occurred, while the inactivation of spores under HS happened (≈3 logs at 200 MPa). HPP prior to HS seems to promote a subsequent inactivation of C. perfringens spores in BHI-broth at pH 4.50, which is less evident for other pHs. For HPP coconut water, the inactivation levels under HS were lower (≈2.0 logs at 200 MPa). The Weibull model well described the inactivation pattern observed. These results suggest that HS/RT can be simultaneously used as a tool to avoid C. perfringens spores' development, as well as for its inactivation, without the application of high temperatures that are required to inactivate these spores.

9.
Foods ; 13(9)2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38731676

ABSTRACT

Nowadays, consumers are more aware of the effects of their diet on their health, and thus demand natural or minimally processed food products. Therefore, research has focused on processes that assure safe products without jeopardizing their nutritional properties. In this context, this work aimed to evaluate the effects of high-pressure processing (550 MPa/3 min/15 °C, HPP) on a fruit salad (composed of melon juice and pieces of Golden apple and Rocha pear) throughout 35 days of storage at 4 °C. For the physicochemical properties analysed (browning degree, polyphenol oxidase activity, antioxidant activity (ABTS assay), and volatile profile), a freshly made fruit salad was used, while for the microbiological tests (total aerobic mesophiles, and yeast and moulds) spoiled melon juice was added to the fruit salad to increase the microbial load and mimic a challenge test with a high initial microbial load. It was determined that processed samples were more microbiologically stable than raw samples, as HPP enabled a reduction of almost 4-log units of both total aerobic mesophiles and yeasts and moulds, as well as an almost 1.5-fold increase in titratable acidity of the unprocessed samples compared to HPP samples. Regarding browning degree, a significant increase (p < 0.05) was observed in processed versus unprocessed samples (roughly/maximum 68%), while the addition of ascorbic acid decreased the browning of the samples by 29%. For antioxidant activity, there were no significant differences between raw and processed samples during the 35 days of storage. An increase in the activity of polyphenol oxidase immediately after processing (about 150%) was confirmed, which was generally similar or higher during storage compared with the raw samples. Regarding the volatile profile of the product, it was seen that the compounds associated with melon represented the biggest relative percentage and processed samples revealed a decrease in the relative quantity of these compounds compared to unprocessed. Broadly speaking, HPP was shown to be efficient in maintaining the stability and overall quality of the product while assuring microbial safety (by inactivating purposely inoculated microorganisms), which allows for longer shelf life (7 versus 28 days for unprocessed and processed fruit salad, respectively).

10.
Semin Neurol ; 44(3): 308-323, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38593854

ABSTRACT

Temperature control in severe acute brain injury (SABI) is a key component of acute management. This manuscript delves into the complex role of temperature management in SABI, encompassing conditions like traumatic brain injury (TBI), acute ischemic stroke (AIS), intracerebral hemorrhage (ICH), aneurysmal subarachnoid hemorrhage (aSAH), and hypoxemic/ischemic brain injury following cardiac arrest. Fever is a common complication in SABI and is linked to worse neurological outcomes due to increased inflammatory responses and intracranial pressure (ICP). Temperature management, particularly hypothermic temperature control (HTC), appears to mitigate these adverse effects primarily by reducing cerebral metabolic demand and dampening inflammatory pathways. However, the effectiveness of HTC varies across different SABI conditions. In the context of post-cardiac arrest, the impact of HTC on neurological outcomes has shown inconsistent results. In cases of TBI, HTC seems promising for reducing ICP, but its influence on long-term outcomes remains uncertain. For AIS, clinical trials have yet to conclusively demonstrate the benefits of HTC, despite encouraging preclinical evidence. This variability in efficacy is also observed in ICH, aSAH, bacterial meningitis, and status epilepticus. In pediatric and neonatal populations, while HTC shows significant benefits in hypoxic-ischemic encephalopathy, its effectiveness in other brain injuries is mixed. Although the theoretical basis for employing temperature control, especially HTC, is strong, the clinical outcomes differ among various SABI subtypes. The current consensus indicates that fever prevention is beneficial across the board, but the application and effectiveness of HTC are more nuanced, underscoring the need for further research to establish optimal temperature management strategies. Here we provide an overview of the clinical evidence surrounding the use of temperature control in various types of SABI.


Subject(s)
Brain Injuries , Hypothermia, Induced , Humans , Hypothermia, Induced/methods , Brain Injuries/therapy , Brain Injuries/physiopathology , Fever/etiology , Fever/therapy
11.
Learn Behav ; 2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38671293

ABSTRACT

To investigate the extent of adoption of more efficient coding strategies, pigeons learned, in three experiments, a symbolic matching-to-sample task that featured an asymmetric sample-comparison mapping. In all experiments, one comparison was correct following one of the samples (one-to-one mapping), and another comparison was correct following the remaining samples (many-to-one mapping). The experiments differed in sample number; Experiment 1 featured three samples, Experiment 2 five samples, and Experiment 3 seven samples. Our goal was to assess the adoption of a single-code/default coding strategy, which establishes two response rules: one rule specific to the sample mapped one-to-one (the single code), and another rule to be applied following any other sample (the default rule). Alternatively, the animals could establish more response rules, one per sample. Thus, the single-code/default strategy allows learning a task via a reduced number of response rules, and the more samples are mapped many-to-one, the greater the savings it allows. As such, the three experiments should progressively be more amenable to the adoption of this strategy. Overall, the adoption of a single-code/default strategy was not widespread. When taken together with previous results, the present study suggests that the amount of training may affect the coding strategy pigeons adopt. Additionally, our results underscore that individual differences are a fundamental aspect to consider when studying learning flexibility.

12.
Behav Processes ; 216: 105006, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38367660

ABSTRACT

A matching-to-sample task with a 3-sample, 2-comparison mapping has been found to engender joint control by the stimuli that signaled the samples (keylight) and the inter-trial interval (houselight), with a trade-off in the degree of control exerted by each stimulus. To learn about the boundary conditions for the establishment of that joint stimulus control, we trained pigeons in a similar task, but featuring a one-to-one sample-comparison mapping, with two samples and two comparisons. To assess their relative influences, we ran two tests where each of the stimuli was removed: in one test, no sample keylight was presented, and in the other, the ITI was spent in darkness. Results were consistent with both stimuli influencing choice but there was no clear evidence of a trade-off between them. These results suggest that sample-comparison mapping and/or total number of samples may influence how an animal directs its attention to the stimuli available.


Subject(s)
Discrimination Learning , Learning , Animals , Columbidae
13.
Carbohydr Polym ; 331: 121880, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38388063

ABSTRACT

Contact lenses (CLs) constitute an advantageous platform for the topical release of corticosteroids due to their prolonged contact with the eye. However, the lipophilic nature of corticosteroids hampers CLs' ability to release therapeutic amounts. Two approaches to improve loading and release of triamcinolone acetonide (TA) from poly(2-hydroxyethyl methacrylate)-based hydrogels were investigated: adding 2-hydroxypropyl-ß-cyclodextrin (HP-ß-CD) to the monomers solution before polymerization (HEMA/i-CD) and an hydrogels' post-treatment with HP-ß-CD (HEMA/p-CD). The effect of HP-ß-CD and sterilization by high hydrostatic pressure (HHP) on the hydrogel properties (water content, oxygen and ion permeability, roughness, transmittance, and stiffness) was evaluated. The HEMA/i-CD hydrogels had stronger affinity for TA, sustaining its release for one day. HHP sterilization promoted the formation of cyclodextrin-TA complexes within the hydrogels, improving their drug-loading capacity ¼60 %. Cytotoxicity and irritability tests confirmed the safety of the therapeutic CLs. TA released from the hydrogels permeated through ocular tissues ex vivo and showed anti-inflammatory activity. Finally, a previously validated mathematical model was used to estimate the ability of the TA-loaded CLs to deliver therapeutic drug concentrations to the posterior part of the eye. Overall, HP-ß-CD-containing CLs are promising candidates for the topical ocular application of TA as an alternative delivery system to intraocular injections.


Subject(s)
Contact Lenses, Hydrophilic , Cyclodextrins , Methacrylates , Triamcinolone Acetonide/pharmacology , 2-Hydroxypropyl-beta-cyclodextrin , Hydrostatic Pressure , Adrenal Cortex Hormones , Hydrogels
14.
Int J Pharm ; 650: 123685, 2024 Jan 25.
Article in English | MEDLINE | ID: mdl-38072146

ABSTRACT

Contact lenses (CLs) have been suggested as drug delivery platforms capable of increasing the drug residence time on the cornea and therefore its bioavailability. However, when targeting the posterior segment of the eye, the drug released from CLs still encounters the barrier effect of the ocular tissues, which considerably reduces the efficacy of administration. This work aims at the development of CLs able to simultaneously deliver an anti-inflammatory drug (dexamethasone sodium phosphate) and a cell-penetrating peptide (penetratin), the latter acting as a drug carrier across the tissues. Hydroxyethyl methacrylate (HEMA)-based hydrogels were functionalized with acrylic acid (AAc) and/or aminopropyl methacrylamide (APMA) to serve as CL materials with increased affinity for the drug and peptide. APMA-functionalized hydrogels sustained the dual release for 8 h, which is compatible with the wearing time of daily CLs. Hydrogels demonstrated suitable light transmittance, swelling capacity and in vitro biocompatibility. The anti-inflammatory activity of the drug was not compromised by the presence of the peptide nor by sterilization. The ocular distribution of the drug after 6 h of CL wearing was evaluated in vivo in rabbits and revealed that the amount of drug in the cornea and aqueous humor significantly increased when the drug was co-delivered with penetratin.


Subject(s)
Cell-Penetrating Peptides , Contact Lenses , Animals , Rabbits , Drug Delivery Systems , Drug Carriers , Dexamethasone , Anti-Inflammatory Agents , Permeability , Hydrogels
15.
Einstein (Säo Paulo) ; 22: eRC0582, 2024. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1564511

ABSTRACT

ABSTRACT The focus of this case report is to technically describe a noninvasive diagnostic evaluation of bow Hunter's syndrome using a dynamic computed tomography angiography protocol and discuss its advantages. In addition, we aimed to exemplify the quality of the study by presenting images of a 3D-printed model generated to help plan the surgical treatment for the patient. The dynamic computed tomography angiography protocol consisted of a first image acquisition with the patient in the anatomic position of the head and neck. This was followed by a second acquisition with the head and neck rotated to the side that triggered the symptoms, with technical parameters similar to the first acquisition. The acquired images were used to print a 3D model to better depict the findings for the surgical team. The dynamic computed tomography angiography protocol developed in this study helped visualize the vertebrobasilar arterial anatomy, detect vertebral artery stenosis produced by head and neck rotation, depict the structure responsible for artery stenosis (e.g., bony structure or membranes), and study possible complications of the disease (e.g., posterior cerebral circulation infarction). Additionally, the 3D-printed model better illustrated the findings of stenosis, aiding in surgical planning. In conclusion, dynamic computed tomography angiography for the evaluation of bow Hunter's syndrome is a feasible noninvasive technique that can be used as an alternative to traditional diagnostic methods.

16.
Mater Today Bio ; 23: 100861, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38058695

ABSTRACT

Bone resident cells are constantly subjected to a range of distinct mechanical loadings, which generates a complex microenvironment. In particular, hydrostatic pressure (HP) has a key impact on modulation of cell function and fate determination. Although HP is a constant mechanical stimulus, its role in regulating the osteogenesis process within a defined 3D microenvironment has not been comprehensively elucidated. Perceiving how environmental factors regulate the differentiation of stem cells is essential for expanding their regenerative potential. Inspired by the mechanical environment of bone, this study attempted to investigate the influence of different ranges of cyclic HP on human adipose-derived mesenchymal stem cells (MSCs) encapsulated within a compartmentalized liquefied microenvironment. Taking advantage of the liquefied environment of microcapsules, MSCs were exposed to cyclic HP of 5 or 50 MPa, 3 times/week at 37 °C. Biological tests using fluorescence staining of F-actin filaments showed a noticeable improvement in cell-cell interactions and cellular network formation of MSCs. These observations were more pronounced in osteogenic (OST) condition, as confirmed by fluorescent staining of vinculin. More interestingly, there was a significant increase in alkaline phosphatase activity of MSCs exposed to 50 MPa magnitude of HP, even in the absence of osteoinductive factors. In addition, a greater staining area of both osteopontin and hydroxyapatite was detected in the 50 MPa/OST group. These findings highlight the benefit of hydrostatic pressure to regulate osteogenesis of MSCs as well as the importance of employing simultaneous biochemical and mechanical stimulation to accelerate the osteogenic potential of MSCs for biomedical purposes.

17.
J Child Neurol ; 38(13-14): 659-664, 2023 12.
Article in English | MEDLINE | ID: mdl-37981797

ABSTRACT

Introduction: We describe 5 children with GFAP astrocytopathy with the goal of further characterizing this rare form of meningoencephalomyelitis. Methods: Retrospective chart review of patients diagnosed with GFAP astrocytopathy between 2019 and 2021. Results: Patients were 8-17 years old, and all were male. Fever, headache, and vomiting were common presenting symptoms, and weakness, tremor, and ataxia were common initial examination findings. Initial magnetic resonance imaging (MRI) showed spinal cord abnormalities in 2 patients and leptomeningeal enhancement in 1. Most patients had cerebral spinal fluid pleocytosis, and all screened negative for malignancy. Three patients progressed to coma, and all were treated with immunosuppressant therapy. By discharge, all patients had improved over their clinical nadir, although none had returned to baseline. Discussion: GFAP astrocytopathy is a recently recognized cause of meningoencephalomyelitis in children. Here, we expand our understanding of this entity with the goal of aiding those treating children with GFAP astrocytopathy.


Subject(s)
Astrocytes , Magnetic Resonance Imaging , Adolescent , Child , Humans , Male , Astrocytes/metabolism , Astrocytes/pathology , Ataxia/pathology , Autoantibodies , Glial Fibrillary Acidic Protein , Retrospective Studies
18.
Learn Behav ; 2023 Nov 20.
Article in English | MEDLINE | ID: mdl-37985603

ABSTRACT

The midsession reversal task involves a simultaneous discrimination between stimuli S1 and S2. Choice of S1 but not S2 is reinforced during the first 40 trials, and choice of S2 but not S1 is reinforced during the last 40 trials. Trials are separated by a constant intertrial interval (ITI). Pigeons learn the task seemingly by timing the moment of the reversal trial. Hence, most of their errors occur around trial 40 (S2 choices before trial 41 and S1 choices after trial 40). It has been found that when the ITI is doubled on a test session, the reversal trial is halved, a result consistent with timing. However, inconsistent with timing, halving the ITI on a test session did not double the reversal trial. The asymmetry of ITI effects could be due to the intrusion of novel cues during testing, cues that preempt the timing cue. To test this hypothesis, we ran two types of tests after the regular training in the midsession reversal task, one with S1 and S2 choices always reinforced, and another with S1 always reinforced but S2 reinforced only after 20 trials when the ITI doubled or 40 trials when the ITI halved. For most pigeons, performance was consistent with timing both when the ITI doubled and when it was halved, but some pigeons appeared to follow strategies based on counting or on reinforcement contingencies.

19.
Foods ; 12(19)2023 Oct 01.
Article in English | MEDLINE | ID: mdl-37835293

ABSTRACT

Dairy cream, a common ingredient in various dishes and food products, is susceptible to rapid microbial growth due to its high water activity (≈0.97) and pH (≈6.7). Thus, it requires proper processing conditions to ensure food safety and extend shelf life. High-pressure processing (HPP) has emerged as a nonthermal food pasteurization method, offering an alternative to conventional heat-based techniques to obtain tastier, fresh-like, and safe dairy products without undesirable heat-induced alterations. This study assessed the impact of HPP (450 and 600 MPa for 5 and 15 min at 7 °C) and thermal pasteurization (75 °C for 15 s) on the microbiological and physicochemical attributes of dairy cream immediately after processing and throughout refrigerated storage (4 °C). HPP-treated samples remained microbiologically acceptable even on the 51st day of storage, unlike thermally pasteurized samples. Moreover, HPP decreased inoculated Escherichia coli and Listeria innocua counts by more than 6 log units to undetectable levels (1.00 log CFU/mL). pH, color (maximum variation of ΔE* up to 8.43), and fatty acid profiles remained relatively stable under varying processing conditions and during storage. However, viscosity exhibited higher values for HPP-treated samples (0.028 ± 0.003 Pa·s) compared to thermally processed ones (0.016 ± 0.002 Pa·s) by the 28th day of storage. Furthermore, volatile compounds (VOCs) of all treated samples presented a tendency to increase throughout storage, particularly acids and aliphatic hydrocarbons. These findings show HPP's potential to significantly extend the shelf life of highly perishable dairy cream by at least 15 days compared to thermal pasteurization.

20.
Biology (Basel) ; 12(9)2023 Sep 06.
Article in English | MEDLINE | ID: mdl-37759611

ABSTRACT

Traditional foods are increasingly valued by consumers, whose attention and purchase willingness are highly influenced by other claims such as 'natural', 'sustainable', and 'clean label'. The purpose of the present study was to evaluate the impact of a novel non-thermal food processing method (i.e., HPP-assisted biocontrol combining mild high hydrostatic pressure, listeriophage Listex, and pediocin PA-1 producing Pediococcus acidilactici) on the succession of bacterial communities and quality of a fermented sausage model. A comparative analysis of instrumental color, texture, and lipid peroxidation revealed no significant differences (p > 0.05) in these quality parameters between non- and minimally processed fermented sausages throughout 60-day refrigerated storage (4 °C). The microbiota dynamics of biotreated and untreated fermented sausages were assessed by 16S rRNA next-generation sequencing, and the alpha and beta diversity analyses revealed no dissimilarity in the structure and composition of the bacterial communities over the analyzed period. The innovative multi-hurdle technology proposed herein holds valuable potential for the manufacture of traditional fermented sausages while preserving their unique intrinsic characteristics.

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