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1.
J Cell Physiol ; 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38212955

RESUMEN

Aging is associated with the steady decline of several cellular processes. The loss of skeletal muscle mass, termed sarcopenia, is one of the major hallmarks of aging. Aged skeletal muscle exhibits a robust reduction in its regenerative capacity due to dysfunction (i.e., senescence, lack of self-renewal, and impaired differentiation) of resident muscle stem cells, called satellite cells. To replicate aging in vitro, immortalized skeletal muscle cells (myoblasts) can be treated with various agents to mimic age-related dysfunction; however, these come with their own set of limitations. In the present study, we used sequential passaging of mouse myoblasts to mimic impaired differentiation that is observed in aged skeletal muscle. Further, we investigated mitochondrial apoptotic mechanisms to better understand the impaired differentiation in these "aged" cells. Our data shows that sequential passaging (>20 passages) of myoblasts is accompanied with significant reductions in differentiation and elevated cell death. Furthermore, high-passage (HP) myoblasts exhibit greater mitochondrial-mediated apoptotic signaling through mitochondrial BAX translocation, CYCS and AIFM1 release, and caspase-9 activation. Finally, we show that inhibition of mitochondrial outer membrane permeability partly recovered differentiation in HP myoblasts. Together, our findings suggests that mitochondrial apoptotic signaling is a contributing factor to the diminished differentiation that is observed in aged myoblasts.

2.
Phys Rev Lett ; 132(9): 093801, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38489636

RESUMEN

We report the first experimental demonstration of the replica symmetry breaking (RSB) phenomenon in a fiber laser system supporting standard mode-locking (SML) regime. Though theoretically predicted, this photonic glassy phase remained experimentally undisclosed so far. We employ an ytterbium-based mode-locked fiber laser with a very rich phase diagram. Two phase transitions are observed separating three different regimes: cw, quasi-mode-locking (QML), and SML. The regimes are intrinsically related to the distinct dynamics of intensity fluctuations in the laser spectra. We set the connection between the RSB glassy phase with frustrated modes and onset of L-shaped intensity distributions in the QML regime, which impact directly the replica overlap measure.

3.
J Biomech Eng ; 146(1)2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37943157

RESUMEN

Joint compressive forces have been identified as a risk factor for osteoarthritis disease progression. Therefore, unloader braces are a common treatment with the aim of relieving pain, but their effects are not clearly documented in the literature. A knee brace concept was tested with the aim of reducing joint loads and pain in knee osteoarthritis patients by applying an extension moment exclusively during the stance phase. The ideal effects were evaluated during gait based on musculoskeletal modeling of six patients, and experimental tests with a prototype brace were conducted on one patient. The effects were evaluated using electromyography measurements and musculoskeletal models to evaluate the muscle activation and knee compressive forces, respectively. The ideal brace simulations revealed a varying reduction of the first peak knee force between 3.5% and 33.8% across six patients whereas the second peak was unaffected. The prototype reduced the peak vasti muscle activation with 7.9% and musculoskeletal models showed a reduction of the first peak knee compressive force of up to 26.3%. However, the prototype brace increased the knee joint force impulse of up to 17.1% and no immediate pain reduction was observed. The reduction of the first peak knee compressive force, using a prototype on a single patient, indicates a promising effect from an applied knee extension moment for reducing knee joint loads during normal gait. However, further clinical experiments with this brace method are required to evaluate the long-term effects on both pain and disease progression in knee osteoarthritis patients.


Asunto(s)
Osteoartritis de la Rodilla , Humanos , Proyectos Piloto , Fenómenos Biomecánicos , Articulación de la Rodilla/fisiología , Marcha/fisiología , Dolor , Progresión de la Enfermedad
4.
Food Microbiol ; 120: 104490, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38431333

RESUMEN

Sporeforming bacteria are a concern in some food raw materials, such as cocoa powder. Samples (n = 618) were collected on two farms and at several stages during cocoa powder manufacture in three commercial processing lines to determine the impact of each stage on bacterial spore populations. Mesophilic aerobic, mesophilic anaerobic, thermophilic aerobic, and Bacillus cereus spore populations were enumerated in all the samples. Genetic diversity in B. cereus strains (n = 110) isolated from the samples was examined by M13 sequence-based PCR typing, partial sequencing of the panC gene, and the presence/absence of ces and cspA genes. The counts of different groups of sporeforming bacteria varied amongst farms and processing lines. For example, the counts of mesophilic aerobic spore-forming (MAS) populations of cocoa bean fermentation were lower than 1 log spore/g in Farm 1 but higher than 4 log spore/g in Farm 2. B. cereus isolated from cocoa powder was also recovered from cocoa beans, nibs, and samples after roasting, refining, and pressing, which indicated that B. cereus spores persist throughout cocoa processing. Phylogenetic group IV was the most frequent (73%), along with processing. Strains from phylogenetic group III (14 %) did not show the ces gene's presence.


Asunto(s)
Bacillus cereus , Chocolate , Bacillus cereus/genética , Filogenia , Anaerobiosis , Esporas Bacterianas/genética , Microbiología de Alimentos , Recuento de Colonia Microbiana
5.
Food Microbiol ; 121: 104531, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38637091

RESUMEN

The present study aimed to assess the occurrence and counts of Staphylococcus aureus in Brazilian artisanal cheeses (BAC) produced in five regions of Brazil: Coalho and Manteiga (Northeast region); Colonial and Serrano (South); Caipira (Central-West); Marajó (North); and Minas Artisanal cheeses, from Araxá, Campos das Vertentes, Cerrado, Serro and Canastra microregions (Southeast). The resistance to chlorine-based sanitizers, ability to attach to stainless steel surfaces, and antibiogram profile of a large set of S. aureus strains (n = 585) were assessed. Further, a total of 42 isolates were evaluated for the presence of enterotoxigenic genes (sea, seb, sec, sed, see, seg, sei, sej, and ser) and submitted to typing using pulsed-field gel electrophoresis (PFGE). BAC presented high counts of S. aureus (3.4-6.4 log CFU/g), varying from 25 to 62.5%. From the S. aureus strains (n = 585) assessed, 16% could resist 200 ppm of sodium hypochlorite, whereas 87.6% produced strong ability to attach to stainless steel surfaces, corroborating with S. aureus ability to persist and spread in the environment. Furthermore, the relatively high frequency (80.5%) of multidrug-resistant S. aureus and the presence of enterotoxin genes in 92.6% of the strains is of utmost attention. It reveals the lurking threat of SFP that can survive when conditions are favorable. The presence of enterotoxigenic and antimicrobial-resistant strains of S. aureus in cheese constitutes a potential risk to public health. This result calls for better control of cheese contamination sources, and taking hygienic measures is necessary for food safety. More attention should be paid to animal welfare and hygiene practices in some dairy farms during manufacturing to enhance the microbiological quality of traditional cheese products.


Asunto(s)
Queso , Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Animales , Staphylococcus aureus/genética , Queso/microbiología , Brasil , Microbiología de Alimentos , Acero Inoxidable/análisis , Enterotoxinas/genética , Leche/microbiología
6.
J Dairy Sci ; 107(1): 155-168, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37709020

RESUMEN

Ohmic heating may improve bioactive compounds and processing, ensuring food safety of beverages, liquid and pasty food, or liquid with solid pieces. Due to those traits, this study conducted a comparison between ohmic heating technology and conventional heating (CH), with a focus on assessing the impact of both methods on functional compounds (such as angiotensin-converting enzyme inhibition, α-amylase and α-glucosidase inhibition, and antioxidant activity) in both fresh and thawed raw sheep milk, which had been frozen for up to 3 mo. Different ohmic heating conditions were applied and compared to CH (3.33-8.33 V/cm vs. CH [73°C/15 s]). A total of 18 peptides with some functional activities were identified by MALDI-TOF mass spectrometry analysis. Ohmic heating samples presented the highest activities related to health, followed by CH and raw milk samples; antioxidant activity range was from 0.11% to 0.71%, antihypertensive activity ranged from 0.20% to 0.72%, and antidiabetic activity ranged from 0.21% to 0.79%. Of 51 volatile compounds detected, some were degraded by freezing, storing, and heating the sheep milk. This study showed for the first time that ohmic heating processing improved sheep milk bioactive peptides and preserved volatile compounds.


Asunto(s)
Antioxidantes , Leche , Animales , Ovinos , Leche/química , Antioxidantes/análisis , Calefacción , Bebidas/análisis , Péptidos/análisis , Calor
7.
An Acad Bras Cienc ; 96(3): e20231121, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38922258

RESUMEN

The study evaluated the use of nano copper in semi-purified diets for laying quails and its effect on performance, metabolic state, and bioavailability. A total of 160 (180-days-old) quails were distributed in a completely randomized design, in a 3x3+1 factorial. The copper sources used were copper sulfate, copper oxide, and nano copper oxide, at levels of 200, 400, and 800 ppm each, totaling nine treatments plus a negative control (with no copper inclusion). The following variables were determined: weight gain, feed intake, egg production, egg weight, hemoglobin, hematocrit, Cu in the tissues and Cu bioavailability. Data were subjected to analysis of variance at 5% probability. The effect of sources and levels, as well as the interaction between the factors were evaluated. When interaction was observed, the effect of sources was evaluated separately by the Tukey's test and the effect of levels by regression, both at 5% probability. Copper nano oxide can be used at up to 800 ppm in the diet of laying quails without altering the productive performance, and with higher bioavailability than conventional copper oxide. Hemoglobin increases with the inclusion of 200 and 400 ppm of nano copper oxide and the hematocrit with 400 ppm.


Asunto(s)
Alimentación Animal , Cobre , Animales , Cobre/análisis , Cobre/administración & dosificación , Femenino , Alimentación Animal/análisis , Disponibilidad Biológica , Codorniz/fisiología , Nanopartículas del Metal/administración & dosificación , Dieta/veterinaria
8.
Int J Mol Sci ; 25(11)2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38892020

RESUMEN

Doxorubicin is an effective drug for cancer treatment; however, cardiotoxicity limits its use. Cardiotoxicity pathophysiology is multifactorial. GLP-1 analogues have been shown to reduce oxidative stress and inflammation. In this study, we evaluated the effect of pretreatment with liraglutide on doxorubicin-induced acute cardiotoxicity. A total of 60 male Wistar rats were allocated into four groups: Control (C), Doxorubicin (D), Liraglutide (L), and Doxorubicin + Liraglutide (DL). L and DL received subcutaneous injection of liraglutide 0.6 mg/kg daily, while C and D received saline for 2 weeks. Afterwards, D and DL received a single intraperitoneal injection of doxorubicin 20 mg/kg; C and L received an injection of saline. Forty-eight hours after doxorubicin administration, the rats were subjected to echocardiogram, isolated heart functional study, and euthanasia. Liraglutide-treated rats ingested significantly less food and gained less body weight than animals that did not receive the drug. Rats lost weight after doxorubicin injection. At echocardiogram and isolated heart study, doxorubicin-treated rats had systolic and diastolic function impairment. Myocardial catalase activity was statistically higher in doxorubicin-treated rats. Myocardial protein expression of tumor necrosis factor alpha (TNF-α), phosphorylated nuclear factor-κB (p-NFκB), troponin T, and B-cell lymphoma 2 (Bcl-2) was significantly lower, and the total NFκB/p-NFκB ratio and TLR-4 higher in doxorubicin-treated rats. Myocardial expression of OPA-1, MFN-2, DRP-1, and topoisomerase 2ß did not differ between groups (p > 0.05). In conclusion, doxorubicin-induced cardiotoxicity is accompanied by decreased Bcl-2 and phosphorylated NFκB and increased catalase activity and TLR-4 expression. Liraglutide failed to improve acute doxorubicin-induced cardiotoxicity in rats.


Asunto(s)
Cardiotoxicidad , Doxorrubicina , Liraglutida , Ratas Wistar , Animales , Liraglutida/farmacología , Liraglutida/uso terapéutico , Doxorrubicina/efectos adversos , Cardiotoxicidad/etiología , Cardiotoxicidad/metabolismo , Masculino , Ratas , Estrés Oxidativo/efectos de los fármacos , Miocardio/metabolismo , Miocardio/patología , FN-kappa B/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Corazón/efectos de los fármacos
9.
J Neurochem ; 166(1): 58-75, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35149997

RESUMEN

Abnormal phase transitions have been implicated in the occurrence of proteinopathies. Disordered proteins with nucleic acidbinding ability drive the formation of reversible micron-sized condensates capable of controlling nucleic acid processing/transport. This mechanism, achieved via liquid-liquid phase separation (LLPS), underlies the formation of long-studied membraneless organelles (e.g., nucleolus) and various transient condensates formed by driver proteins. The prion protein (PrP) is not a classical nucleic acid-binding protein. However, it binds nucleic acids with high affinity, undergoes nucleocytoplasmic shuttling, contains a long intrinsically disordered region rich in glycines and evenly spaced aromatic residues, among other biochemical/biophysical properties of bona fide drivers of phase transitions. Because of this, our group and others have characterized LLPS of recombinant PrP. In vitro phase separation of PrP is modulated by nucleic acid aptamers, and depending on the aptamer conformation, the liquid droplets evolve to solid-like species. Herein, we discuss recent studies and previous evidence supporting PrP phase transitions. We focus on the central role of LLPS related to PrP physiology and pathology, with a special emphasis on the interaction of PrP with different ligands, such as proteins and nucleic acids, which can play a role in prion disease pathogenesis. Finally, we comment on therapeutic strategies directed at the non-functional phase separation that could potentially tackle prion diseases or other protein misfolding disorders.


Asunto(s)
Ácidos Nucleicos , Enfermedades por Prión , Priones , Animales , Proteínas Priónicas/metabolismo , Priones/metabolismo , Mamíferos/metabolismo , Ácidos Nucleicos/metabolismo
10.
Opt Lett ; 48(9): 2297-2300, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37126258

RESUMEN

By employing the optical Kerr gate technique at 800 nm with 180 fs pulses at 76 MHz, we evaluated the third-order nonlinear optical response of two-dimensional (2D) semiconducting MoS2, semimetallic ZrTe2, and metallic NbS2 and NbSe2. The modulus of the nonlinear refractive index was measured to range from 8.6 × 10-19 m2/W to 5.3 × 10-18 m2/W, with all materials' response time limited by the pulse duration. The physical mechanism to explain the ultrafast response time's origin considers the nature of the 2D material, as will be discussed.

11.
Int J Behav Nutr Phys Act ; 20(1): 64, 2023 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-37259093

RESUMEN

BACKGROUND: There is limited evidence on what shapes the acceptability of population level dietary and active-travel policies in England. This information would be useful in the decision-making process about which policies should be implemented and how to increase their effectiveness and sustainability. To fill this gap, we explored public and policymakers' views about factors that influence public acceptability of dietary and active-travel policies and how to increase public acceptability for these policies. METHODS: We conducted online, semi-structured interviews with 20 members of the public and 20 policymakers in England. A purposive sampling frame was used to recruit members of the public via a recruitment agency, based on age, sex, socioeconomic status and ethnicity. Policymakers were recruited from existing contacts within our research collaborations and via snowball sampling. We explored different dietary and active-travel policies that varied in their scope and focus. Interviews were transcribed verbatim and analysed using thematic reflexive analysis with both inductive and deductive coding. RESULTS: We identified four themes that informed public acceptability of dietary and active-travel policies: (1) perceived policy effectiveness, i.e., policies that included believable mechanisms of action, addressed valued co-benefits and barriers to engage in the behaviour; (2) perceived policy fairness, i.e., policies that provided everyone with an opportunity to benefit (mentioned only by the public), equally considered the needs of various population subgroups and rewarded 'healthy' behaviours rather than only penalising 'unhealthy' behaviours; (3) communication of policies, i.e., policies that were visible and had consistent and positive messages from the media (mentioned only by policymakers) and (4) how to improve policy support, with the main suggestion being an integrated strategy addressing multiple aspects of these behaviours, inclusive policies that consider everyone's needs and use of appropriate channels and messages in policy communication. CONCLUSIONS: Our findings highlight that members' of the public and policymakers' support for dietary and active-travel policies can be shaped by the perceived effectiveness, fairness and communication of policies and provide suggestions on how to improve policy support. This information can inform the design of acceptable policies but can also be used to help communicate existing and future policies to maximise their adoption and sustainability.


Asunto(s)
Dieta , Política de Salud , Humanos , Investigación Cualitativa , Formulación de Políticas , Comunicación
12.
Environ Res ; 220: 114771, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36586712

RESUMEN

Contaminated irrigation water is among many potential vehicles of human pathogens to food plants, constituting significant public health risks especially for the fresh produce category. This review discusses some available guidelines or regulations for microbiological safety of irrigation water, and provides a summary of some common methods used for characterizing microbial contamination. The goal of such exploration is to understand some of the considerations that influence formulation of water testing guidelines, describe priority microbial parameters particularly with respect to food safety risks, and attempt to determine what methods are most suitable for their screening. Furthermore, the review discusses factors that influence the potential for microbiologically polluted irrigation water to pose substantial risks of pathogenic contamination to produce items. Some of these factors include type of water source exploited, irrigation methods, other agro ecosystem features/practices, as well as pathogen traits such as die-off rates. Additionally, the review examines factors such as food safety knowledge, other farmer attitudes or inclinations, level of social exposure and financial circumstances that influence adherence to water testing guidelines and other safe water application practices. A thorough understanding of relevant risk metrics for the application and management of irrigation water is necessary for the development of water testing criteria. To determine sampling and analytical approach for water testing, factors such as agricultural practices (which differ among farms and regionally), as well as environmental factors that modulate how water quality may affect the microbiological safety of produce should be considered. Research and technological advancements that can improve testing approach and the determination of target levels for hazard characterization or description for the many different pollution contexts as well as farmer adherence to testing requirements, are desirable.


Asunto(s)
Frutas , Verduras , Humanos , Frutas/microbiología , Ecosistema , Inocuidad de los Alimentos , Agricultura , Calidad del Agua , Riego Agrícola , Microbiología del Agua
13.
Environ Res ; 223: 115443, 2023 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-36781014

RESUMEN

Some Escherichia coli serotypes are important human pathogens causing diarrhea or in some cases, life threatening diseases. E. coli is also a typical indicator microorganism, routinely used for assessing the microbiological quality of water especially to indicate fecal contamination. The soil is a sink and route of transmission to water and food resources and it is thus important to understand the survival of enterotoxigenic E. coli strains in soil. This study monitored the survival of six E. coli strains in sandy and loam soil. Furthermore, since biochar is a commonly used soil conditioner, the study investigated the impact of biochar amendment (15%) on the survival of the E. coli strains in (biochar-amended) sandy and loam soils. Addition of biochar affected the physicochemical properties of both soils, altering potassium levels, calcium, magnesium, sodium as well as levels of other metal ions. It increased the organic matter of loam soil from 44 g/dm3 to 52 g/dm3, and increased the pH of both sandy and loam soils. Survival and persistence of the E. coli strains generally varied according to soil type, with strains generally surviving better (P ≤ 0.05) in loam soil compared to in sandy soil. In loam soil and biochar amended loam soils, E. coli strains remained culturable until the 150th day with counts ranging between 3.00 and 5.94 ± 0.04 log CFU/g. The effects of biochar on the physicochemical properties of soil and the response of the E. coli strains to biochar amendment was variable depending on soil type.


Asunto(s)
Escherichia coli Enterotoxigénica , Contaminantes del Suelo , Humanos , Suelo/química , Carbón Orgánico/química , Arena , Contaminantes del Suelo/análisis
14.
Environ Res ; 237(Pt 1): 116907, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37597829

RESUMEN

In this study, the probability of occurrence of fumonisins in corn in the states of greatest production in Brazil was determined. The data were analyzed through quantitative risk analysis using the Monte Carlo simulation. The results indicated that there is a strong correlation between fumonisins contamination levels and the geographical region due to the influence of climatic characteristics, with temperature having the main influence. The Southern states presented higher risks of occurrence and concentration levels of fumonisins in corn due to the temperate climate with lower average temperature and higher relative humidity and precipitation indices. Cultivation in the best season indicates a significant reduction in the production of fumonisins when this period was evaluated, with average concentration levels up to 42% lower. The generated data are important for regulatory agencies and the agricultural sector, which needs to be aware that the chance of success in grain production depends on efficient planning of the growing season, mainly concerning the climatic conditions to which it is subject to minimize the risks.

15.
Appl Opt ; 62(8): LA1-LA2, 2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-37133108

RESUMEN

The 2022 Latin America Optics and Photonics Conference (LAOP 2022), the major international conference sponsored by Optica in Latin America, returned to Recife, Pernambuco, Brazil, after its first edition in 2010. Held every two years since (except for 2020), LAOP has the explicit objective to promote Latin American excellence in optics and photonics research and support the regional community. In the 6th edition in 2022, it featured a comprehensive technical program with recognized experts in fields critical to Latin America, highly multidisciplinary, with themes from biophotonics to 2D materials. The 191 attendees of LAOP 2022 listened to five plenary speakers, 28 keynotes, 24 invited talks, and 128 presentations, including oral and posters.

16.
J Eur Acad Dermatol Venereol ; 37(10): 1999-2003, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37210649

RESUMEN

BACKGROUND: Breslow thickness, patient age and ulceration are the three most valuable clinical and pathological predictors of melanoma survival. A readily available reliable online tool that accurately considers these and other predictors could be valuable for clinicians managing melanoma patients. OBJECTIVE: To compare online melanoma survival prediction tools that request user input on clinical and pathological features. METHODS: Search engines were used to identify available predictive nomograms. For each, clinical and pathological predictors were compared. RESULTS: Three tools were identified. The American Joint Committee on Cancer tool inappropriately rated thin tumours as higher risk than intermediate tumours. The University of Louisville tool was found to have six shortcomings: a requirement for sentinel node biopsy, unavailable input of thin melanoma or patients over 70 years of age and less reliable hazard ratio calculations for age, ulceration and tumour thickness. The LifeMath.net tool was found to appropriately consider tumour thickness, ulceration, age, sex, site and tumour subtype in predicting survival. LIMITATIONS: The authors did not have access to the base data used to compile various prediction tools. CONCLUSION: The LifeMath.net prediction tool is the most reliable for clinicians in counselling patients with newly diagnosed primary cutaneous melanoma regarding their survival prospects.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Humanos , Anciano , Anciano de 80 o más Años , Melanoma/patología , Neoplasias Cutáneas/patología , Pronóstico , Biopsia del Ganglio Linfático Centinela , Supervivencia sin Enfermedad
17.
Food Microbiol ; 116: 104368, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37689415

RESUMEN

The risk of fungal spoilage of sports drinks produced in the beverage industry was assessed using quantitative microbial spoilage risk assessment (QMSRA). The most relevant pathway was the contamination of the bottles during packaging by mould spores in the air. Mould spores' concentration was estimated by longitudinal sampling for 6 years (936 samples) in different production areas and seasons. This data was analysed using a multilevel model that separates the natural variability in spore concentration (as a function of sampling year, season, and area) and the uncertainty of the sampling method. Then, the expected fungal contamination per bottle was estimated by Monte Carlo simulation, considering their settling velocity and the time and exposure area. The product's shelf life was estimated through the inoculation of bottles with mould spores, following the determination of the probability of visual spoilage as a function of storage time at 20 and 30 °C using logistic regression. The Monte Carlo model estimated low expected spore contamination in the product (1.7 × 10-6 CFU/bottle). Nonetheless, the risk of spoilage is still relevant due to the large production volume and because, as observed experimentally, even a single spore has a high spoilage potential. The applicability of the QMSRA during daily production was made possible through the simplification of the model under the hypothesis that no bottle will be contaminated by more than one spore. This simplification allows the calculation of a two-dimensional performance objective that combines the spore concentration in the air and the exposure time, defining "acceptable combinations" according to an acceptable level of spoilage (ALOS; the proportion of spoiled bottles). The implementation of the model at the operational level was done through the representation of the simplified model as a two-dimensional diagram that defines acceptable and unacceptable areas. The innovative methodology employed here for defining and simplifying QMSRA models can be a blueprint for future studies aiming to quantify the risk of spoilage of other beverages with a similar scope.


Asunto(s)
Bebidas , Contaminación de Alimentos , Microbiología de Alimentos , Hongos , Bebidas/microbiología , Microbiología del Aire , Instalaciones Industriales y de Fabricación , Hongos/aislamiento & purificación
18.
Int J Biometeorol ; 67(5): 897-911, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37041373

RESUMEN

We set out to determine the impact of moderate heat load on the plasma concentrations of a suite of hormones involved in regulating energy metabolism and feed intake. The responses of the thermally challenged (TC) feedlot steers were compared to those of feed restricted thermoneutral (FRTN) steers. Two sequential cohorts of twelve 518 ± 23 kg Black Angus steers on finisher grain ration were housed in climate-controlled rooms (CCR) for 18 days and returned to outdoor pens for 40 days. The TC group was subjected to a diurnal range of 28-35 °C for 7 days (Challenge) but held in thermoneutral conditions beforehand (PreChallenge), and in Recovery (after Challenge). The FRTN group was held in thermoneutral conditions and feed restricted throughout. Blood was collected over the three periods in CCR and two periods in outdoor pens for 40 days (PENS and Late PENS). Plasma concentrations of prolactin, thyroid stimulating hormone, insulin, leptin, adiponectin and thyroxine (T4) were determined during the five periods. Whilst the pituitary hormones were relatively stable, there were differences in plasma leptin, adiponectin and T4 between the two groups during Challenge and Recovery, and occasionally in PENS. The interaction of the plasma hormone concentrations and rumen temperature and DMI were also investigated. Whilst the positive relationship between DMI and leptin was confirmed, we found a strong negative relationship between adiponectin and rumen temperature, and a strong positive relationship between adiponectin and dry matter intake (DMI) in the TC steers only.


Asunto(s)
Calor , Leptina , Bovinos , Animales , Adiponectina , Alimentación Animal/análisis , Ingestión de Alimentos/fisiología , Dieta/veterinaria
19.
Sensors (Basel) ; 23(10)2023 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-37430507

RESUMEN

This paper presents novel current sensorless maximum-power point-tracking (MPPT) algorithms based on compensators/controllers and a single-input voltage sensor. The proposed MPPTs eliminate the expensive and noisy current sensor, which can significantly reduce the system cost and retain the advantages of the widely used MPPT algorithms, such as Incremental Conductance (IC) and Perturb and Observe (P&O) algorithms. Additionally, it is verified that the proposed algorithms, especially the proposed Current Sensorless V based on PI, can reach outstanding tracking factors (TFs) such as the IC and P&O based on PI algorithms. In this sense, the insertion of controllers inside the MPPT gives them adaptive characteristics, and the experimental TFs are in the remarkable range of more than 99%, with an average yield of 99.51% and a peak of 99.80%.

20.
BMC Genomics ; 23(1): 126, 2022 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-35151275

RESUMEN

Identifying the genes underlying fitness-related traits such as body size and male ornamentation can provide tools for conservation and management and are often subject to various selective pressures. Here we performed high-depth whole genome re-sequencing of pools of individuals representing the phenotypic extremes for antler and body size in white-tailed deer (Odocoileus virginianus). Samples were selected from a tissue repository containing phenotypic data for 4,466 male white-tailed deer from Anticosti Island, Quebec, with four pools representing the extreme phenotypes for antler and body size after controlling for age. Our results revealed a largely homogenous population but detected highly divergent windows between pools for both traits, with the mean allele frequency difference of 14% for and 13% for antler and body SNPs in outlier windows, respectively. Genes in outlier antler windows were enriched for pathways associated with cell death and protein metabolism and some of the most differentiated windows included genes associated with oncogenic pathways and reproduction, processes consistent with antler evolution and growth. Genes associated with body size were more nuanced, suggestive of a highly complex trait. Overall, this study revealed the complex genomic make-up of both antler morphology and body size in free-ranging white-tailed deer and identified target loci for additional analyses.


Asunto(s)
Cuernos de Venado , Ciervos , Animales , Ciervos/genética , Genómica , Humanos , Masculino , Oncogenes , Fenotipo
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