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1.
J Dairy Sci ; 104(9): 10310-10323, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34176631

RESUMO

Several reports have indicated that udder surface temperature (UST) can be a useful indicator of subclinical mastitis (SCM). The objective was to evaluate UST by infrared thermography (IRT) as a diagnostic tool for SCM and intramammary infection (IMI), and to assess the influence of environmental conditions in the potential diagnosis of this disease in dairy cows located at high-altitude tropical regions. A total of 105 cows (397 quarters) from 3 dairy farms with mechanical and manual milking methods were enrolled in the study. Subclinical mastitis was diagnosed when quarter samples had a somatic cell count (SCC) ≥200 × 103 cells/mL, microbial growth (MG) was defined when a major pathogen (≥1 cfu/plate) or Corynebacterium spp. (≥10 cfu/plate) was isolated, and IMI was defined as the presence of MG and SCC ≥100 × 103 cells/mL. Infrared images were taken with a thermal camera placed 1 m away from the udder, and shots of the rear and left and right lateral view were made during the morning milking, before any manipulation of the udder and employing dark cardboard on the contralateral side to avoid artifacts in the background. A multilevel mixed effects linear regression model clustered within cows and herd was performed to evaluate the associations with UST. Clinical performance was evaluated using the Youden index to establish the optimum UST thresholds, which were set at 32.6°C for any case definition when milking was by hand, at 33.7°C for MG, and at 34°C for SCM and IMI in machine-milked quarters. Sensitivity (Se), specificity (Sp), area under curve (AUC), and positive likelihood ratio (+LR) were also assessed. Test agreement was assessed by kappa coefficient (κ). The UST of healthy quarters ranged between (95% CI) 32.4 and 32.6°C, lower than SCM quarters (n = 88) at 32.9°C (95% CI: 32.7-33.1 °C), MG quarters (n = 56) at 33.5°C (95% CI: 33.3-33.7°C), and IMI quarters (n = 50) at 33.5°C (95% CI: 33.2-33.7 °C). The UST was also related to the milking method: higher temperatures were observed for hand milking (n = 90) compared with machine milking (n = 185). No relation between environmental conditions such as wind speed, atmospheric temperature, relative humidity, and temperature-humidity index and UST were observed during this study. For hand milking, the optimal UST threshold was 32.6°C; for SCM, Se = 0.53, Sp = 0.89, AUC = 0.71, κ = 0.4; for MG, Se = 0.83, Sp = 0.93, AUC = 0.88, κ = 0.77; and for IMI, Se = 0.82, Sp = 0.92, AUC = 0.87, κ = 0.74. The machine milking threshold for SCM resulted in Se = 0.42, Sp = 0.97, AUC = 0.70, κ = 0.47; for MG, Se = 0.82, Sp = 0.89, AUC = 0.85, κ = 0.60; and for IMI, Se = 0.82, Sp = 0.98, AUC = 0.90, κ = 0.79. These findings suggest that UST determined by IRT is higher in machine-milked cows and in quarters with MG and IMI than in healthy quarters; therefore, UST by IRT is a reliable, clinically useful method for MG and IMI diagnosis.


Assuntos
Doenças dos Bovinos , Mastite Bovina , Mastite , Animais , Bovinos , Contagem de Células/veterinária , Feminino , Glândulas Mamárias Animais , Mastite/diagnóstico , Mastite/veterinária , Mastite Bovina/diagnóstico , Leite , Temperatura , Termografia/veterinária
2.
Sensors (Basel) ; 21(22)2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34833605

RESUMO

This work presents a design for an automatized multiposition dynamic wheelchair used to transport quadriplegic patients by reconfiguring a manual wheelchair structure. An electric actuator is attached to a four-bar mechanism fixed to each side of a wheelchair's backrest to reach multiposition. The entire device is actuated through a PID controller. An experimental test is carried out in a simplified wheelchair structure. Finally, the structure of the wheelchair is evaluated through the Dynamic analysis and Finite Element Method under the payload computed with the most critical position reached by the mechanism.


Assuntos
Cadeiras de Rodas , Desenho de Equipamento , Humanos
3.
Molecules ; 25(18)2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32933083

RESUMO

Microalgae, including cyanobacteria, represent a valuable source of natural compounds that have remarkable bioactive properties. Each microalga species produces a mixture of antioxidants with different amounts of each compound. Three aspects are important in the production of bioactive compounds: the microalga species, the medium composition including light supplied and the photobioreactor design, and operation characteristics. In this study, the antioxidant content and productivity performance of four microalgae were assessed in batch and continuous cultures. Biomass productivity by the four microalgae was substantially enhanced under continuous cultivation by 5.9 to 6.3 times in comparison with batch cultures. The energetic yield, under the experimental conditions studied, ranged from 0.03 to 0.041 g biomass kJ-1. Phenols, terpenoids, and alkaloids were produced by Spirulinaplatensis, Isochrysisgalbana, and Tetraselmissuecica, whereas tocopherols and carotenoids were produced by the four microalgae, except for phycocyanin and allophycocyanin, which were only produced by S. platensis and Porphyridiumcruentum. The findings demonstrate that the continuous cultivation of microalgae in photobioreactors is a convenient method of efficiently producing antioxidants.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Microalgas/metabolismo , Alcaloides/química , Biomassa , Carotenoides/química , Meios de Cultura , Haptófitas/metabolismo , Luz , Fenóis/química , Fotobiorreatores , Ficocianina/química , Espectroscopia de Infravermelho com Transformada de Fourier , Spirulina/metabolismo , Superóxido Dismutase/química , Terpenos/química , Tocoferóis/química
4.
Sensors (Basel) ; 17(6)2017 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-28613250

RESUMO

In this paper, a Least Mean Square (LMS) programming scheme is used to set the offset voltage of two operational amplifiers that were built using floating-gate transistors, enabling a 0.95 VRMS trimmer-less flame detection sensor. The programming scheme is capable of setting the offset voltage over a wide range of values by means of electron injection. The flame detection sensor consists of two programmable offset operational amplifiers; the first amplifier serves as a 26 µV offset voltage follower, whereas the second amplifier acts as a programmable trimmer-less voltage comparator. Both amplifiers form the proposed sensor, whose principle of functionality is based on the detection of the electrical changes produced by the flame ionization. The experimental results show that it is possible to measure the presence of a flame accurately after programming the amplifiers with a maximum of 35 LMS-algorithm iterations. Current commercial flame detectors are mainly used in absorption refrigerators and large industrial gas heaters, where a high voltage AC source and several mechanical trimmings are used in order to accurately measure the presence of the flame.

5.
Foods ; 13(12)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38928817

RESUMO

Packaging design is pivotal in motivating consumer decisions, as a key communication tool from creation to purchase. Currently, the interpretation and evaluation of packaging's impact are shifting toward non-traditional methods. This pilot study evaluated the packaging perception of York Ham and Turkey Breast products. The event-related potential (ERP) technique, the methodology priming words (positive and negative), and target images (original and modified packaging) were applied. A total of 23 participants were sampled using a 32-channels scalp elastic electrode cap and viewed 200 trials of word-image matching. Participants responded whether the images and adjectives matched or not, using the two groups of images. The results demonstrate an N400 effect in the parietal area. This region was observed to show evidence of cognitive processing related to congruency or incongruency, by contrasting the priming and target of this study. The evaluation positioned the York Ham packaging as the best rated. The findings show a relevant contribution to ERPs and research related to the food packaging perception.

6.
Behav Processes ; 221: 105083, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39094759

RESUMO

Predator-prey interactions are the interspecific relationships of greatest interest in ecology. Spiders are among the most diverse and ubiquitous terrestrial predators on the planet. Their large dietary breadth is often linked with the development of specific predatory behaviors and morphological adaptations. However, studies on the predatory behavior of spiders have mostly focused on specialist species, leaving behind the ethological variability occurring in generalist species that allow them to respond to the different prey types. For three species of generalist wandering spiders, we searched images of predation events on the Internet to determine the most common prey. Subsequently, the focal predator species were then used in behavioral experiments. Using high-speed videos, handling patterns for different prey types (spider and cricket) were analyzed. Our results show a notable difference in handling patterns between prey types. We found that the spider prey was often rotated around the axis allowing the predator to bite in the ventral region of the prey and thus avoid a counterattack. Contrary, crickets were arbitrarily rotated. Our work may be an indication that these three species of generalist spiders have a preference for manipulating prey differently with a preference to rotate spiders, allowing them to exploit prey with various defensive mechanisms.


Assuntos
Gryllidae , Comportamento Predatório , Aranhas , Animais , Aranhas/fisiologia , Comportamento Predatório/fisiologia , Gryllidae/fisiologia , Especificidade da Espécie , Animais Peçonhentos
7.
Microbiol Resour Announc ; 11(9): e0034722, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35938819

RESUMO

Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4) is the causal agent of Fusarium wilt, a major threat to the banana industry worldwide. Here, we report the genome of a Foc TR4 strain from Peru, sequenced using a combination of Illumina and Oxford Nanopore Technologies.

8.
Comput Math Methods Med ; 2022: 8650071, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36050998

RESUMO

The aim of this paper is to model the dynamics of the human papillomavirus (HPV) in cervical epithelial cells. We developed a mathematical model of the epithelial cellular dynamics of the stratified epithelium of three (basale, intermedium, and corneum) stratums that is based on three ordinary differential equations. We determine the biological condition for the existence of the epithelial cell homeostasis equilibrium, and we obtain the necessary and sufficient conditions for its global stability using the method of Lyapunov functions and a theorem on limiting systems. We have also developed a mathematical model based on seven ordinary differential equations that describes the dynamics of HPV infection. We calculated the basic reproductive number (R 0) of the infection using the next-generation operator method. We determine the existence and the local stability of the equilibrium point of the cellular homeostasis of the epithelium. We then give a sufficient condition for the global asymptotic stability of the epithelial cell homeostasis equilibrium using the Lyapunov function method. We proved that this equilibrium point is nonhyperbolic when R 0 = 1 and that in this case, the system presents a forward bifurcation, which shows the existence of an infected equilibrium point when R 0 > 1. We also study the solutions numerically (i.e., viral kinetic in silico) when R 0 > 1. Finally, local sensitivity index was calculated to assess the influence of different parameters on basic reproductive number. Our model reproduces the transient, acute, latent, and chronic infections that have been reported in studies of the natural history of HPV.


Assuntos
Alphapapillomavirus , Infecções por Papillomavirus , Células Epiteliais , Humanos , Modelos Biológicos , Papillomaviridae , Infecção Persistente
9.
Artigo em Inglês | MEDLINE | ID: mdl-35432495

RESUMO

Background: Scorpions can use their pincers and/or stingers to subdue and immobilize their prey. A scorpion can thus choose between strategies involving force or venom, or both, depending on what is required to subdue its prey. Scorpions vary greatly in the size and strength of their pincers, and in the efficacy of their venom. Whether this variability is driven by their defensive or prey incapacitation functionis unknown. In this study, we test if scorpion species with different pincer morphologies and venom efficacies use these weapons differently during prey subjugation. To that end, we observed Opisthacanthus elatus and Chactas sp. with large pincers and Centruroides edwardsii and Tityus sp. with slender pincers. Methods: The scorpion pinch force was measured, and behavioral experiments were performed with hard and soft prey (Blaptica dubia and Acheta domesticus). Stinger use, sting frequency and immobilization time were measured. Results: We found that scorpions with large pincers such as O. elatus produce more force and use the stinger less, mostly subjugating prey by crushing them with the pincers. In C. edwardsii and Tityus sp. we found they use their slender and relatively weak pincers for holding the prey, but seem to predominantly use the stinger to subjugate them. On the other hand, Chactas sp. uses both strategies although it has a high pinch force. Conclusions: Our results show that scorpionspecies with massive pincers and high pinch force as O. elatus use the stinger less for prey subjugation than scorpionspecies with slenderpincers.

10.
Healthcare (Basel) ; 10(3)2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35327042

RESUMO

A breakthrough in peritoneal dialysis (PD) therapy occurred in 1977 with the development of continuous ambulatory peritoneal dialysis (CAPD). Its simplicity, low cost, and ease with which CAPD could be performed on patients at home contributed to the popularity of this procedure. However, there is a need for continuous improvement in building optimal systems for incident chronic kidney disease (CKD) patients. This research showed the design and construction of a simplified prototype of low-cost automated peritoneal dialysis (APD) equipment that meets international standards to automatically regulate infusion and fluid drainage in and out of a patient with low margins of error. Experimental tests allowed the adjustment of the RPM values concerning the flow rate provided. In addition, thanks to the pressure sensor, it was possible to observe a fluctuation ranging from 9 to 13 kPa, which is within the permissible average specified in the catalogs of medical instruments and equipment. Furthermore, a turbidity sensor was added to decrease the possibility of presenting peritonitis. The results showed absolute values of flow, angular velocity, and pressure that it could deliver for use in APD therapies. Finally, the construction of the APD equipment is presented generally, showing the electronic and mechanical components that constitute it.

11.
Materials (Basel) ; 14(11)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070453

RESUMO

Biofuels represent an energy option to mitigate polluting gases. However, technical problems must be solved, one of them is to improve the combustion process. In this study, the geometry of a piston head for a diesel engine was redesigned. The objective was to improve the combustion process and reduce polluting emissions using biodiesel blends as the fuel. The methodology used was the mechanical engineering design process. A commercial piston (base piston) was selected as a reference model to assess the piston head's redesign. Changes were applied to the profile of the piston head based on previous research and a new model was obtained. Both models were evaluated and analyzed using the finite element method, where the most relevant physical conditions were temperature and pressure. Numerical simulations in the base piston and the new piston redesign proposal presented similar behaviors and results. However, with the proposed piston, it was possible to reduce the effort and the material. The proposed piston profile presents adequate results and behaviors. In future, we suggest continuing conducting simulations and experimental tests to assess its performance.

12.
Children (Basel) ; 8(12)2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-34943373

RESUMO

This work presents a non-invasive methodology to obtain a three-dimensional femur model of three-year-old infants affected with Osteogenesis Imperfecta (OI) type III. DICOM® Files of a femur were processed to obtain a finite element model to assess the transverse, the oblique, and the comminuted fractures. The model is evaluated under a normal walking cycle. The loads applied were considered the most critical force generated on the normal walking cycle, and the analyses considered anisotropic bone conditions. The outcome shows stress concentration areas in the central zone of the diaphysis of the femur, and the highest levels of stress occur in the case of the comminuted fracture, while the transverse fracture presents the lowest values. Thus, the method can be helpful for determining the bone fracture behavior of certain pathologies, such as osteogenesis imperfecta, osteopenia, and osteoporosis.

13.
Front Psychol ; 11: 570470, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33071901

RESUMO

The use of visual attention for evaluating consumer behavior has become a relevant field in recent years, allowing researchers to understand the decision-making processes beyond classical self-reports. In our research, we focused on using eye-tracking as a method to understand consumer preferences in children. Twenty-eight subjects with ages between 7 and 12 years participated in the experiment. Participants were involved in two consecutive phases. The initial phase consisted of the visualization of a set of stimuli for decision-making in an eight-position layout called Alternative Forced-choice. Then the subjects were asked to freely analyze the set of stimuli, they needed to choose the best in terms of preference. The sample was randomly divided into two groups balanced by gender. One group visualized a set of icons and the other a set of toys. The final phase was an independent assessment of each stimulus viewed in the initial phase in terms of liking/disliking using a 7-point Likert scale. Sixty-four stimuli were designed for each of the groups. The visual attention was measured using a non-obstructive eye-tracking device. The results revealed two novel insights. Firstly, the time of fixation during the last four visits to each stimulus before the decision-making instant allows us to recognize the icon or toy chosen from the eight alternatives with a 71.2 and 67.2% of accuracy, respectively. The result supports the use of visual attention measurements as an implicit tool to analyze decision-making and preferences in children. Secondly, eye movement and the choice of liking/disliking choice are influenced by stimuli design dimensions. The icon observation results revealed how gender samples have different fixation and different visit times which depend on stimuli design dimension. The toy observations results revealed how the materials determinate the largest amount fixations, also, the visit times were differentiated by gender. This research presents a relevant empirical data to understand the decision-making phenomenon by analyzing eye movement behavior. The presented method can be applied to recognize the choice likelihood between several alternatives. Finally, children's opinions represent an extra difficulty judgment to be determined, and the eye-tracking technique seen as an implicit measure to tackle it.

14.
Toxins (Basel) ; 11(11)2019 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-31717836

RESUMO

Spiders rely on venom to catch prey and few species are even capable of capturing vertebrates. The majority of spiders are generalist predators, possessing complex venom, in which different toxins seem to target different types of prey. In this study, we focused on the trophic ecology and venom toxicity of Phoneutria boliviensis F. O. Pickard-Cambridge, 1897, a Central American spider of medical importance. We tested the hypothesis that its venom is adapted to catch vertebrate prey by studying its trophic ecology and venom toxicity against selected vertebrate and invertebrate prey. We compared both trophic ecology (based on acceptance experiments) and toxicity (based on bioassays) among sexes of this species. We found that P. boliviensis accepted geckos, spiders, and cockroaches as prey, but rejected frogs. There was no difference in acceptance between males and females. The venom of P. boliviensis was far more efficient against vertebrate (geckos) than invertebrate (spiders) prey in both immobilization time and LD50. Surprisingly, venom of males was more efficient than that of females. Our results suggest that P. boliviensis has adapted its venom to catch vertebrates, which may explain its toxicity to humans.


Assuntos
Interações Hospedeiro-Parasita , Comportamento Predatório , Venenos de Aranha/toxicidade , Aranhas/parasitologia , Vertebrados/parasitologia , Animais , América Central , Feminino , Masculino
17.
Cir Cir ; 75(1): 57-61, 2007.
Artigo em Espanhol | MEDLINE | ID: mdl-17470327

RESUMO

Italian universities have been distinguished since their beginnings, within different specialties. One of them, if not the most important, is the teaching of medicine. One of the leaders is the University of Padua, founded in 1222, establishing itself as the second most important institution after the University of Bologna. In spite of the difficulties faced by this university, as with most other universities during the medieval period, it continued to perform and consolidate once again during the Renaissance as one of the most outstanding universities in Europe. The University of Bologna and the University of Padua shared the leadership in teaching during this period. At the University of Padua, the lectures were always full with teachers and students of great fame, such as Andreas Vesalio, Gabriele Falopio, William Harvey, Giovanni Battista Morgagni, Antonio Scarpa, to name just a few. In this article we discuss the rights the University had since it beginnings, from its establishment to the Renaissance, and the great influence of some of the teachers and students in the art and science of medicine.


Assuntos
Médicos/história , Faculdades de Medicina/história , Universidades/história , História do Século XVI , História do Século XVII , História do Século XVIII , Itália
18.
Rev Invest Clin ; 58(2): 170-6, 2006.
Artigo em Espanhol | MEDLINE | ID: mdl-16827269

RESUMO

The foundation date of the University of Bologna was 1150, was the first European University and set the pattern. The combination of structured teaching and students association marked the origin of the studium generale. The presence of teaching legists encouraged teachers in others fields to come to Bologna. Ars dictaminis, grammar, logic, philosophy, mathematical arts and especially medicine were taught there by the middle of the thirteenth century. The university had to offer advanced instruction in law, medicine, and theology, had a minimum of six to eight professors teaching civil law, canon law, medicine, logic, natural philosophy and usually rhetoric. Many professors bearing local names were able scholars and commanding figures in medicine and surgery. Taddeo Alderotti (1210-95) began to teach medicine in Bologna about 1260. He soon raised medicine to a prestigious position in the university. The geographical distribution demonstrates the international character of the student body 73% were Italians and 26% non Italians. The decision of the commune of Bologna to wrest control of the university from the students by paying professors was probably the most important decision in the history of Italian universities. Examination of the distribution of professors offers a detailed picture of the faculty. In 1370 the university had 11 professors of civil law, seven professors of canon law, three professors of medical theory, two of medical practice (the specific of diagnosis and treatment), and one professor of surgery. After growing steadily the numbers of teachers stabilized at 85 to 110 until 1530.


Assuntos
Educação Médica/história , Universidades/história , História do Século XV , História do Século XVI , História Medieval , Itália
19.
Cir Cir ; 74(5): 397-404, 2006.
Artigo em Espanhol | MEDLINE | ID: mdl-17224112

RESUMO

The University of Bologna was founded in 1150 and was the first European University to establish this educational trend. The combination of structured teaching and student associations marked the origin of the studium generale. The presence of teaching legists encouraged teachers in others fields to come to Bologna. Ars dictaminis, grammar, logic, philosophy, mathematics and especially medicine were taught there by the middle of the thirteenth century. The university offered advanced instruction in law, medicine, and theology and had a minimum of six to eight professors teaching civil law, canonical law, medicine, logic, natural philosophy and usually rhetoric. Many professors bearing local names were learned scholars and commanding figures in medicine and surgery. Taddeo Alderotti (1210-1295) began to teach medicine in Bologna in about 1260. He soon raised medicine to a prestigious position in the university. The geographical distribution demonstrates the international distribution of the student body: 73% were Italians and 26% non-Italians. The decision of the legislature of Bologna to take control of the university from the students by paying professors was probably the most important decision in the history of Italian universities. Examination of the distribution of professors offers a detailed picture of the faculty. In 1370 the university had 11 professors of civil law, 7 professors of canonical law, 3 professors of medical theory, 2 professors of medical practice (specifically of diagnosis and treatment), and 1 professor of surgery. After growing steadily, the numbers of teachers stabilized at 85 to 110 until the year 1530.


Assuntos
Universidades/história , Currículo , Docentes de Medicina/história , História do Século XV , História do Século XVI , História Medieval , Humanos , Itália , Faculdades de Medicina/história , Universidades/organização & administração
20.
Cir Cir ; 73(2): 151-8, 2005.
Artigo em Espanhol | MEDLINE | ID: mdl-15910710

RESUMO

The interest in the physical perfection and the corporal forms brings as a result the creation of new anatomical studies. The anatomical knowledge progressed in the second half of the XV century, conceiving the knowledge of the human body as a basic reality of Medicine. One of the greater contributions of the Italian Universities to medicine was the teaching of anatomy. The Universities of Padua, Bologna, and Pisa educated in their classrooms great physicians like Andres Vesalio, Gabriel Fallopio, Realdo Colombo, Mondino de Luzzi, Julio Ceasar Aranzio, and Gaspare Tagliacozzi, among others. The teaching of anatomy during the Renaissance was characterized by the development of dissection techniques and autopsy practice, which was recognized as an extremely valuable skill for anatomical study. The dissections were made in circular amphitheatres in the following way: a Medicine professor read the text book, another one made the dissection, and a third one indicated the structures referred.


Assuntos
Anatomia/história , Cirurgia Geral/história , História do Século XV , História do Século XVI , História do Século XVII , Humanos , Itália
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