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1.
J Phys Chem A ; 128(34): 7073-7083, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39150222

RESUMO

A new method to investigate disorder in ice films is proposed and applied to acetylene ice. It is based on a quantitative analysis of the infrared spectrum data, which includes: the Brendel-Bormann model for the material's dielectric function; molecular vibration modes calculated by density functional theory (DFT); a monomer-dimer model for amorphous ice; and a peak-shape analysis through Levenberg-Marquardt nonlinear regression. Acetylene ice films with different degrees of disorder were investigated with the proposed method. The results provide an estimate of the degree of disorder in the films and indicate the possibility of existence of a second amorphous phase of acetylene ice grown at temperatures of about 15 K and then annealed. This phase would be similar to the high-density amorphous phase observed for water ice. The infrared data in this work is compared with those from the literature for acetylene gas, acetylene film, and acetylene aerosol. A qualitative analysis reveals differences in the degree of disorder in each system and points to a crystallinity limit for acetylene ice film; that is, the crystalline acetylene film has a higher degree of intrinsic disorder than the crystalline acetylene aerosol.

2.
Phys Rev E ; 109(4-2): 045106, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38755827

RESUMO

We carry out an in-depth analysis of a recently introduced vortex gas model of homogeneous and isotropic turbulence. Direct numerical simulations are used to provide a concrete physical interpretation of one of the model's constituent fields: the degree of vortex polarization. Our investigations shed light on the complexity underlying vortex interactions and reveal, furthermore, that despite some striking similarities, classical and quantum turbulence exhibit distinct structural characteristics, even at inertial range scales. Crucially, these differences arise due to correlations between the polarization and circulation intensity within vortex clusters.

3.
Animal ; 18(2): 101064, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38232659

RESUMO

In beef cattle, the selection for higher weights at young ages has been questioned with the argument that this criterion may increase the adult weight of cows, resulting in higher costs. Therefore, selection criteria should be employed to increase weights at young ages with minimal impact on the adult weight of cows. Additionally, the relationship between measures of cow production efficiency and other well-established selection criteria in breeding programs remains poorly understood. The objective of this study was to longitudinally evaluate the relationship between the weaning index (WIndex) as a measure of efficiency and growth traits of the cows. Possible changes over time in WIndex due to selection applied for yearling weight (YW) were also investigated. The WIndex was proposed to maximize genetic response in the weaning weight of the calf while maintaining genetic gain in BW of the cow at zero. A random regression model was adopted to estimate correlations between WIndex, BW, hip height (HH), and body condition score (BCS) using records of Nelore cows from three lines. Genetic trends were calculated for the control line (NeC) and lines selected for greater YW (NeS and NeT). The age of 3 years was the most critical for the weaning efficiency of the cows. At this stage, young cows are still growing and wean lighter calves than their adult counterparts. The genetic correlation estimates between WIndex and BW (-0.58 to 0.04), HH (-0.05 to -0.34), and BCS (-0.51 to -0.17) were close to zero or negative. BW and HH were strongly correlated genetically across all ages (0.73-0.76). In general, HH exhibited a weak and negative genetic relationship with BCS. The genetic correlation between BW and BCS was stronger for advanced ages (0.45-0.68). In lines selected for YW, important increases in WIndex were observed. However, NeS has been selected since the 1980s until the present for YW, and thus, it showed a more pronounced trend of increasing BW and, consequently, a more modest trend of increasing WIndex compared to NeT. In contrast, WIndex exhibited a trend close to zero for NeC. In this context, monitoring HH and BCS can be useful to avoid losses in the weaning efficiency of cows. Furthermore, we suggest that one way to mitigate efficiency losses in calf production could involve stabilizing the BW of cows and increasing the weaning weight of calves using the WIndex.


Assuntos
Desmame , Feminino , Bovinos/genética , Animais , Peso Corporal/genética , Fenótipo
4.
J Anim Breed Genet ; 141(2): 207-219, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38010317

RESUMO

For decades, inbreeding in cattle has been evaluated using pedigree information. Nowadays, inbreeding coefficients can be obtained using genomic information such as runs of homozygosity (ROH). The aims of this study were to quantify ROH and heterozygosity-rich regions (HRR) in a subpopulation of Guzerá dual-purpose cattle, to examine ROH and HRR islands, and to compare inbreeding coefficients obtained by ROH with alternative genomic inbreeding coefficients. A subpopulation of 1733 Guzerá animals genotyped for 50k SNPs was used to obtain the ROH and HRR segments. Inbreeding coefficients by ROH (FROH ), by genomic relationship matrix based on VanRaden's method 1 using reference allele frequency in the population (FGRM ), by genomic relationship matrix based on VanRaden's method 1 using allele frequency fixed in 0.5 (FGRM_0.5 ), and by the proportion of homozygous loci (FHOM ) were calculated. A total of 15,660 ROH were identified, and the chromosome with the highest number of ROH was BTA6. A total of 4843 HRRs were identified, and the chromosome with the highest number of HRRs was BTA23. No ROH and HRR islands were identified according to established criteria, but the regions closest to the definition of an island were examined from 64 to 67 Mb of BTA6, from 36 to 37 Mb of BTA2 and from 0.50 to 1.25 Mb of BTA23. The genes identified in ROH islands have previously been associated with dairy and beef traits, while genes identified on HRR islands have previously been associated with reproductive traits and disease resistance. FROH was equal to 0.095 ± 0.084, and its Spearman correlation with FGRM was low (0.44) and moderate-high with FHOM (0.79) and with FGRM_0.5 (0.80). The inbreeding coefficients determined by ROH were higher than other cattle breeds' and higher than pedigree-based inbreeding in the Guzerá breed obtained in previous studies. It is recommended that future studies investigate the effects of inbreeding determined by ROH on the traits under selection in the subpopulation studied.


Assuntos
Genoma , Endogamia , Bovinos/genética , Animais , Homozigoto , Genoma/genética , Genótipo , Genômica/métodos , Polimorfismo de Nucleotídeo Único
6.
Braz J Biol ; 83: e272003, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37162072

RESUMO

The lack of water during crop growth causes damage to any production system, especially when it occurs during the initial establishment or beginning of the reproductive stage. Although cotton can be properly managed in regions with water limitation, its yield is affected at different levels according to the genetics of the cultivar adopted. Exogenous application of some organic components has shown a stress-mitigating effect and can be a valuable procedure to enhance the yield of water stress-sensitive cultivars. The objective of this work was to evaluate the benefits of exogenous application of pyruvic acid (100 µM) in cotton plants under water deficit varying the phenological stage of the crop. The experiment was conducted in a greenhouse, where the plants were grown in pots and subjected to seven days of water suspension, initiated individually in stages V2 and B1. Each pot contained two plants. The treatments adopted were: T1 - control, T2 - water suppression; and T3 - water suppression + pyruvate application. The design was randomized blocks in a factorial scheme (3 × 3) with three replicates. The reductions in gas exchange and growth of the cultivars BRS Seridó, CNPA 7MH and FM 966 were more significant in the reproductive stage, especially for FM 966, which was more sensitive. Pyruvate application reduced the effects of water suppression on boll production by 31% in BRS Seridó and 34% in CNPA 7MH and FM 966.


Assuntos
Gossypium , Ácido Pirúvico , Ácido Pirúvico/farmacologia , Gossypium/genética , Reprodução
8.
Braz. j. biol ; 83: e272003, 2023. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1439641

RESUMO

The lack of water during crop growth causes damage to any production system, especially when it occurs during the initial establishment or beginning of the reproductive stage. Although cotton can be properly managed in regions with water limitation, its yield is affected at different levels according to the genetics of the cultivar adopted. Exogenous application of some organic components has shown a stress-mitigating effect and can be a valuable procedure to enhance the yield of water stress-sensitive cultivars. The objective of this work was to evaluate the benefits of exogenous application of pyruvic acid (100 µM) in cotton plants under water deficit varying the phenological stage of the crop. The experiment was conducted in a greenhouse, where the plants were grown in pots and subjected to seven days of water suspension, initiated individually in stages V2 and B1. Each pot contained two plants. The treatments adopted were: T1 - control, T2 - water suppression; and T3 - water suppression + pyruvate application. The design was randomized blocks in a factorial scheme (3 × 3) with three replicates. The reductions in gas exchange and growth of the cultivars BRS Seridó, CNPA 7MH and FM 966 were more significant in the reproductive stage, especially for FM 966, which was more sensitive. Pyruvate application reduced the effects of water suppression on boll production by 31% in BRS Seridó and 34% in CNPA 7MH and FM 966.


A falta d'água durante o crescimento da cultura traz prejuízos em qualquer sistema de produção, especialmente quando ocorre durante o estabelecimento inicial ou início da fase reprodutiva. O algodoeiro, apesar de ter larga habilidade para manejo em regiões com limitação hídrica, tem o rendimento afetado, com níveis diferenciados em função da genética do cultivar adotado. A aplicação exógena de alguns componentes orgânicos tem demonstrado efeito mitigador do estresse podendo ser um aditivo valioso para impulsionar a produtividade de cultivares sensíveis ao estresse hídrico. Neste trabalho, objetivou-se avaliar os benefícios da aplicação exógena de ácido pirúvico (100 µM) em algodoeiros sob déficit hídrico variando a fase fenológica da cultura. O ensaio foi conduzido em casa de vegetação, onde as plantas foram cultivadas em vasos e submetidas a sete dias de suspensão hídrica, iniciadas, individualmente, nas fases V2 e B1. Cada vaso conteve duas plantas. Os tratamentos adotados foram: T1- controle, T2 - supressão hídrica; T3- supressão hídrica + aplicação de piruvato. O delineamento foi em blocos casualizados em esquema fatorial (3 × 3) com três repetições. Foi observado que as reduções nas trocas gasosas e crescimento das cultivares BRS Seridó, CNPA 7MH e FM 966 foram mais expressivas na fase reprodutiva, especialmente da última que se mostrou mais sensível. A aplicação de piruvato mitigou os efeitos da supressão hídrica sobre a produção de capulhos 31% na BRS Seridó e 34% em CNPA 7MH e FM 966.


Assuntos
Ácido Pirúvico/administração & dosagem , Gossypium , Desidratação/tratamento farmacológico
9.
Rev. bras. ciênc. avic ; 25(2): eRBCA-2022-1728, 2023. graf, tab
Artigo em Inglês | VETINDEX | ID: biblio-1434068

RESUMO

We assessed the extent to which CO2 levels altered different hatching and chick parameters. In Experiments 1 and 2, a total of 16,184 eggs from Cobb 500 breeders were incubated in single stage incubators under three different conditions: (a) standard ventilated incubator (CON, Exp.1 and 2); (b) increasing CO2 levels during the first 10 days of incubation until 0.7% (V7000, Exp. 1) and (c) until 0.8% (V8000, Exp. 2). High levels of CO2 improved hatchability, possibly due to lower embryo mortality from ED18 to ED21. Internal and external pipping in experiment V8000 started later than in CON; nevertheless, the hatch still occurred before in V8000 as a result of the shorter durations of external pipping and hatch. In Experiment 3, a total of 12,138 eggs from Cobb 500 were incubated in single stage incubators under three different conditions: (a) standard ventilated incubator (CON); (b) increasing CO2 levels until 1.0% with ventilation (V10000); and (c) increasing CO2 levels until 1.0% without ventilation (NV10000). Hypercapnic conditions led to better hatchability and lower embryo mortality from ED18 to ED21. Internal pipping started earlier in NV10000, but only V10000 differed from CON in terms of the average time for hatch. Hypercapnic groups also showed shorter durations of external pipping and hatch when compared to CON. Post-hatch analysis revealed no differences among incubation conditions in terms of body weight gain, feed conversion ratio, mortality by sudden death syndrome, and production factor. Nevertheless, V10000 showed a lower mortality by ascites and a better viability when compared to CON, while NV10000 presented a higher mortality by other causes. Altogether, our findings indicate that in addition to not being detrimental to embryo survival, high CO2 levels reduce embryonic mortality at 18-21 days of incubation and increase hatchability.(AU)


Assuntos
Animais , Embrião de Galinha/crescimento & desenvolvimento , Mortalidade Fetal , Desenvolvimento Embrionário
14.
Phys Rev E ; 106(5-1): 054121, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36559442

RESUMO

Recent numerical explorations of extremely intense circulation fluctuations at high Reynolds number flows have brought to light novel aspects of turbulent intermittency. Vortex gas modeling ideas, which are related to a picture of turbulence as a dilute system of vortex tube structures, have been introduced alongside such developments, leading to accurate descriptions of the core and the intermediate tails of circulation probability distribution functions (cPDFs), as well as the scaling exponents associated to statistical moments of circulation. We extend the predictive reach of the vortex gas picture of turbulence by emphasizing that multifractality breaking, one of its salient phenomenological ingredients, is the key concept to disclose the asymptotic form of cPDF tails. A remarkable analytical agreement is found with previous results derived within the framework of the instanton approach to circulation intermittency, a functional formalism devised to single out the statistically dominant velocity configurations associated to extreme circulation events.

15.
Arq. bras. med. vet. zootec. (Online) ; 74(5): 759-766, Sep.-Oct. 2022. tab, graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1403421

RESUMO

Platelet rich plasma samples from 50 healthy horses of five different breeds (Thoroughbreds - TB, Brazilian Criollo Horses - BCH, Brazilian Sport Horses - BSH, Miniature Horses - MH and Crossbred Horses - CB), were investigated as to breed, age, and gender effect for platelet concentration. Moreover, a score for physical analysis was established to correlate PRP physical aspect with platelet count. Platelet count was performed by an automatic hematology analyzer and by manual count. PRP physical analysis was based on color, aspect, and capacity to separate blood components. MH showed significant higher platelet concentration than BSH (p<0.05), while the other breed comparisons showed no significant difference. There was no significant difference for gender but there was a weak correlation of age with PRP platelet concentrations (rs = -0.24). Most of the PRP presented yellow color, the separation of blood components showed no correlation, but the aspect showed a moderate correlation (rs = 0.30) with platelet count. Results suggest that PRP platelet concentration can be influenced by intrinsic factors such as breed. Additionally, the analysis of PRP aspect can help to evaluate the quality of the product when there is no access to platelet counts.


Amostras de plasma rico em plaquetas de 50 cavalos saudáveis, de cinco raças diferentes (Puro Sangue de Corrida, Crioula, Brasileiro de Hipismo, Pônei Brasileiro e sem raça definida), foram investigadas quanto à concentração plaquetária em relação à raça, à idade e ao sexo. Além disso, um escore foi estabelecido para correlacionar o aspecto físico do PRP com a contagem plaquetária. A contagem celular foi realizada por um analisador hematológico automático e pelo método manual. A análise física baseou-se na cor, no aspecto e na capacidade de separar hemocomponentes. Pôneis tiveram concentração plaquetária significativamente maior que os Brasileiros de Hipismo (P<0,05), mas as demais comparações entre raças não apresentaram diferença quanto à contagem plaquetária. Não houve diferença para o gênero, mas a idade demonstrou correlação fraca com as concentrações plaquetárias do PRP (rs = -0,24). A maioria dos PRPs apresentaram coloração amarela, e a separação dos hemocomponentes não mostrou correlação com a contagem plaquetária, mas o aspecto apresentou uma correlação moderada (rs = 0,30). Os resultados deste estudo sugerem que a concentração plaquetária do PRP pode ser influenciada por fatores intrínsecos, como a raça. Além disso, a análise do aspecto do PRP pode ajudar na avaliação da qualidade do produto quando não há acesso à contagem plaquetária.


Assuntos
Animais , Masculino , Feminino , Condicionamento Físico Animal/estatística & dados numéricos , Contagem de Plaquetas/veterinária , Plasma Rico em Plaquetas , Cavalos/genética , Fatores Etários
16.
Phys Rev E ; 106(2): L023101, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36109933

RESUMO

The small-scale statistical properties of velocity circulation in classical homogeneous and isotropic turbulent flows are assessed through a modeling framework that brings together the multiplicative cascade and the structural descriptions of turbulence. We find that vortex structures exhibit short-distance repulsive correlations, which is evidenced when they are "tomographically" investigated, by means of planar cuts of the flow, as two-dimensional vortex gases. This phenomenon is suggested from model improvements which allow us to obtain an accurate multiscale description of the intermittent fluctuations of circulation. Its crucial new ingredient, the conjectured hard disk behavior of the effective planar vortices, is then found to be strongly supported from a study of their spatial distributions in direct numerical simulations of the Navier-Stokes equations.

17.
Braz J Med Biol Res ; 55: e12116, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35976270

RESUMO

Cisplatin is an effective antineoplastic agent, but its use is limited by its nephrotoxicity caused by the oxidative stress in tubular epithelium of nephrons. On the other hand, regular exercise provides beneficial adaptations in different tissues and organs. As with many drugs, dosing is extremely important to get the beneficial effects of exercise. Thus, we aimed to investigate the influence of exercise intensity and frequency on cisplatin-induced (20 mg/kg) renal damage in mice. Forty male Swiss mice were divided into five experimental groups (n=8 per group): 1) sedentary; 2) low-intensity forced swimming, three times per week; 3) high-intensity forced swimming, three times per week; 4) low-intensity forced swimming, five times per week; and 5) high-intensity forced swimming, five times per week. Body composition, renal structure, functional indicators (plasma urea), lipid peroxidation, antioxidant enzyme activity, expression of genes related to antioxidant defense, and inflammatory and apoptotic pathways were evaluated. Comparisons considered exercise intensity and frequency. High lipid peroxidation was observed in the sedentary group compared with trained mice, regardless of exercise intensity and frequency. Groups that trained three times per week showed more benefits, as reduced tubular necrosis, plasma urea, expression of CASP3 and Rela (NFkB subunit-p65) genes, and increased total glutathione peroxidase activity. No significant difference in Nfe2l2 (Nrf2) gene expression was observed between groups. Eight weeks of regular exercise training promoted nephroprotection against cisplatin-mediated oxidative injury. Exercise frequency was critical for nephroprotection.


Assuntos
Antioxidantes , Cisplatino , Animais , Antioxidantes/farmacologia , Cisplatino/toxicidade , Peroxidação de Lipídeos , Masculino , Camundongos , Estresse Oxidativo , Natação , Ureia
18.
Dent Mater ; 38(8): 1404-1418, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35787894

RESUMO

OBJECTIVE: Evaluate the effect of different restorative filling techniques on the residual shrinkage stress (ShrS), cuspal strain (CS), depth of cure (DC), and enamel crack formation (Ec) in molars with MOD restorations. METHODS: Post-gel shrinkage, elastic modulus, compressive and diametral tensile strength of the Filtek One Bulk Fill composite were calculated. Sixty molars with MOD preparations were restored using four filling techniques: Bulk; Horizontal; Oblique; Natural enamel and dentin substitution (NEDS) technique. CS was measured using a strain gauge (n = 10). The DC (n = 5) was measured using Knoop hardness. Shrinkage stress/strain was analyzed using 3D finite element analysis. The Ec analysis was carried out by transillumination. Two-way ANOVA with repeated measures and Tukey's HSD test (α = 0.05) was performed for the CS data. Two-Way ANOVA and Tukey's HSD test was performed for the DC data (α = 0.05). RESULTS: CS was higher at the lingual cusp for the horizontal and NEDS technique. No statistical difference was found between the buccal and lingual CS values for the Bulk (p = 0.367) or Oblique techniques (p = 0.192). CS values were lower for the Bulk. More enamel cracks were found for the Bulk. DC was lower at 4 mm regardless the filling technique. The Horizontal showed the highest ShrS values. The Bulk generated the lower ShrS values. SIGNIFICANCE: A Bulk technique caused the lowest shrinkage stress/strain. An Oblique technique yielded the best balance between stress, strain and crack formation. NEDS technique is a good alternative to decrease the number of increments while maintaining the stress levels nearby the Oblique technique.


Assuntos
Resinas Compostas , Restauração Dentária Permanente , Esmalte Dentário , Restauração Dentária Permanente/métodos , Análise do Estresse Dentário , Teste de Materiais , Dente Molar , Polimerização
19.
J Dairy Sci ; 105(6): 5462-5470, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35450708

RESUMO

We conducted a retrospective cohort study to evaluate risk factors associated with clinical mastitis in dairy cows in southern Chile between the first milk test after calving to 200 d in milk (DIM). Data from 8,772 cows were collected from June 2017 to November 2019 on 10 dairy farms selected by convenience in southern Chile. Data were analyzed using a multivariable mixed logistic regression using a manual backward selection process with logit link function and farm as a random effect. The dependent variable was clinical mastitis between the first milking sample collected by monthly milk sampling program up to 200 DIM. Days in milk, fat, urea, parity, season, and somatic cell counts were statistically associated with clinical mastitis in the first 200 d in milk. Cows with higher than average milk yield, parity, urea, and somatic cell count were at greater odds of being diagnosed with clinical mastitis compared with their respective referents. In contrast, higher milk fat was associated with lower odds of clinical mastitis. Significant interactions between days in milk with season and parity were observed, where for every 5-d increase in DIM, the odds of clinical mastitis decreased by different proportions depending on the interaction. Identified risk factors for clinical mastitis using first monthly milk sampling data can help dairy farmers in Chile implement herd-level mastitis prevention and control measures.


Assuntos
Mastite Bovina , Animais , Bovinos , Contagem de Células/veterinária , Chile/epidemiologia , Indústria de Laticínios , Fazendas , Feminino , Humanos , Lactação , Mastite Bovina/tratamento farmacológico , Leite , Gravidez , Estudos Retrospectivos , Fatores de Risco , Ureia
20.
Cryobiology ; 106: 55-65, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35443195

RESUMO

Breeding snakes in captivity has become more and more relevant due not only to the growing interest on their venoms but also to the increasing number of endangered species worldwide. Unfortunately, studies on the formation of germplasm banks for these reptiles do not follow the same pace, and literature on sperm cryopreservation remains in its infancy when compared to other taxa. Herein, we first validated a sperm-egg binding assay (using chicken egg perivitelline membrane - EPM) and some nonfluorescent staining techniques for semen analysis of two pit viper genera (Bothrops and Crotalus), and then we investigated the protective effects of dimethylacetamide (DMA), dimethylformamide (DMF), and dimethylsulfoxide (DMSO) at different concentrations (3, 6 and 12%) throughout the freezing process in five species of lancehead and one of rattlesnake. Our validation process showed high correlations among sperm functional tests (including sperm-binding to EPM) and motion parameters. A total of 166 fresh ejaculates were acquired from 233 collection attempts, and 63.9% of these samples exhibited minimal motility for freezing (≥20%). During cryopreservation we observed that post-thaw motility and quality was improved by higher levels of cryoprotectants (CPA), regardless the CPA type. Lower concentrations of CPA were less harmful to sperm motility and progressive motility following the equilibrium phase, but were ineffective in protecting these cells from the freeze-thaw cycle. Likewise, higher CPA concentrations increased post-thaw integrity of the acrosome and plasma membrane for most species, except for rattlesnakes in which only 12% DMSO produced better outcomes.


Assuntos
Crotalinae , Preservação do Sêmen , Animais , Criopreservação/métodos , Crioprotetores/farmacologia , Dimetil Sulfóxido/farmacologia , Congelamento , Glicerol/farmacologia , Masculino , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Espermatozoides
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