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1.
Nanotechnology ; 34(7)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36347028

RESUMO

The capability of generating magnetically soft and hard phases in a material is important in many aspects, ranging from basic science to applications. Here, the emergence of soft and hard magnetic phases is reported in Fe nanowire (NW) arrays with a diameter of 35 nm fabricated by using a pulsed electrochemical deposition method in porous aluminum oxide templates under different current density (Cd) values in the range of 25-100 mA cm-2. The variation ofCdinfluences the grain size, crystallinity, electrodeposition efficiency and length of the Fe NWs, as characterized by x-ray diffraction, high-resolution transmission electron microscopy, vibrating sample magnetometry and field-emission scanning electron microscopy. IncreasingCdfrom 25 to 80 mA cm-2results in a significant decrease in coercivity and squareness from 1590 to 900 Oe and 0.9 to 0.5, respectively, inducing the soft and hard phases along the length of Fe NWs. Further increasing theCdleads to the separation of the phases, as evidenced by first-order reversal curve analysis. From a theoretical aspect, the emergence of the soft phase may lead to the occurrence of the fanning reversal mode in the NWs, for which there is no precedent in previous experimental investigations.

2.
J Insect Sci ; 21(2)2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33861348

RESUMO

The potential of the parasitoid Psyllaephagus bliteus Riek for the biological control of the eucalyptus pest Glycaspis brimblecombei Moore (Hemiptera: Aphalaridae) nymphs is high. This research sought to analyze the courtship, male competition, and mating behavior of P. bliteus at the proportions of 1:1 and 2:1 males to female in a Petri dish (5 cm diameter), and to describe the ovary histology of virgin and mated females of this parasitoid. At 1:1, males touch the antennae and thorax-abdomen of females during courtship, but females avoid mate attempts before they are 48 h old. At 2:1, the competition between male parasitoids inhibits mating. The histology of ovaries of virgin and mated P. bliteus females is similar, with two well-defined germarium and vitellarium regions, with oocytes at different developmental stages, including mature ones rich in yolk and with eggshell. A clearer understanding of the reproductive behavior and histology of P. bliteus aids in the use of this parasitoid for the biological control of G. brimblecombei.


Assuntos
Himenópteros/anatomia & histologia , Himenópteros/fisiologia , Comportamento Sexual Animal , Animais , Corte , Feminino , Hemípteros/crescimento & desenvolvimento , Hemípteros/parasitologia , Interações Hospedeiro-Parasita , Controle de Insetos , Masculino , Ninfa/parasitologia , Ovário/anatomia & histologia , Controle Biológico de Vetores
3.
J Exp Zool B Mol Dev Evol ; 332(3-4): 81-91, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30964605

RESUMO

Most teleostean embryos develop and hatch without parental assistance, though some receive parental care. We focused on a paternal brood-care species, the barred-chin blenny (Rhabdoblennius nitidus [Günther, 1861]). As hatching approached, fanning behavior by the male parent drastically increased and then embryos hatch. In the absence of the male parent, most embryos failed to hatch. However, the hatching rate was greatly assisted by introducing an artificial water current, suggesting that paternal assistance other than for aeration is required for successful embryo hatching. Next, we analyzed genes for the hatching enzyme and egg-envelope protein, which were successfully cloned from barred-chin blenny, and found the expression patterns differed from those of other euteleosts. Generally, high choriolytic enzyme swells the intact egg envelope, and then low choriolytic enzyme solubilizes the swollen envelope. The expression levels of both the enzymes, but especially the latter, were much lower in barred-chin blenny that is known in most other oviparous species. In addition, the main component of the egg envelope was changed into ChgHm and choriogenin L (ChgL) in barred-chin blenny, whereas ChgH and ChgL for other euteleosts. These in barred-chin blenny would result in ineffective egg-envelope digestion because the posthatching egg envelopes were observed to be swollen but not solubilized. Male parental assistance by fanning until hatching may compensate for this insufficiency. Our study illustrates an example of the evolution of parent-embryo interaction built on a novel relationship: Degradation of the hatching enzyme/egg-envelope digestion system, accompanied by male parental hatching assistance.


Assuntos
Comportamento Animal , Peixes/fisiologia , Poder Familiar , Animais , Clonagem Molecular , DNA Complementar/genética , Embrião não Mamífero , Feminino , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Peixes/genética , Regulação da Expressão Gênica/fisiologia , Masculino , Fatores de Tempo
4.
J Exp Biol ; 220(Pt 12): 2203-2209, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28404729

RESUMO

Honey bees (Apis mellifera) are remarkable fliers that regularly carry heavy loads of nectar and pollen, supported by a flight system - the wings, thorax and flight muscles - that one might assume is optimized for aerial locomotion. However, honey bees also use this system to perform other crucial tasks that are unrelated to flight. When ventilating the nest, bees grip the surface of the comb or nest entrance and fan their wings to drive airflow through the nest, and a similar wing-fanning behavior is used to disperse volatile pheromones from the Nasonov gland. In order to understand how the physical demands of these impeller-like behaviors differ from those of flight, we quantified the flapping kinematics and compared the frequency, amplitude and stroke plane angle during these non-flight behaviors with values reported for hovering honey bees. We also used a particle-based flow visualization technique to determine the direction and speed of airflow generated by a bee performing Nasonov scenting behavior. We found that ventilatory fanning behavior is kinematically distinct from both flight and scenting behavior. Both impeller-like behaviors drive flow parallel to the surface to which the bees are clinging, at typical speeds of just under 1 m s-1 We observed that the wings of fanning and scenting bees frequently contact the ground during the ventral stroke reversal, which may lead to wing wear. Finally, we observed that bees performing Nasonov scenting behavior sometimes display 'clap-and-fling' motions, in which the wings contact each other during the dorsal stroke reversal and fling apart at the start of the downstroke. We conclude that the wings and flight motor of honey bees comprise a multifunctional system, which may be subject to competing selective pressures because of its frequent use as both a propeller and an impeller.


Assuntos
Abelhas/fisiologia , Voo Animal , Comportamento de Nidação , Asas de Animais/fisiologia , Movimentos do Ar , Animais , Fenômenos Biomecânicos , Feromônios/química , Ventilação
5.
Bull Entomol Res ; 107(4): 439-447, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27974053

RESUMO

Cotesia urabae is a solitary larval endoparasitoid that was introduced into New Zealand in 2011 as a classical biological control agent against Uraba lugens. A detailed knowledge of its reproductive biology is required to optimize mass rearing efficiency. In this study, the courtship and mating behaviour of C. urabae is described and investigated from a series of experiments, conducted to understand the factors that influence male mating success. Cotesia urabae males exhibited a high attraction to virgin females but not mated females, whereas females showed no attraction to either virgin or mated males. Male mating success was highest in the presence of a male competitor. Also, the time to mate was shorter and copulation duration was longer when a male competitor was present. Larger male C. urabae had greater mating success than smaller males when paired together with a single female. This knowledge can now be utilized to improve mass rearing methods of C. urabae for the future.


Assuntos
Comportamento Sexual Animal , Vespas , Animais , Tamanho Corporal , Comportamento Competitivo , Feminino , Masculino
6.
Int J Biol Macromol ; 279(Pt 4): 135484, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39250994

RESUMO

The study aimed to develop a novel eutecto-oleogel and its characterizations. Using starch, beeswax, oil, and natural deep eutectic solvents (NADES), an oleogel with low hardness and high liquid fat was developed. The addition of starch and NADES in oleogels caused the formation of new intra or intermolecular hydrogen bonding and improved the oil binding capacity, thermal behavior, and texture of the oleogels. The oleogel with 1 % starch formed a strong gel with the most favorable functional, textural, flow properties and a high fanning factor. Complementary tests of the oleogel exhibited shear thinning and frequency-independent behavior, with zero residual effect. Non-isothermal crystallization and melting analysis of the oleogels showed noticeable differences among the various oleogels. These results contribute to a better understanding of oleo gelation in rice bran oil-based oleogels with NADES, and beeswax for formulating food, pharmaceutical, and personal care products with desired physical properties.


Assuntos
Compostos Orgânicos , Reologia , Amido , Ceras , Amido/química , Compostos Orgânicos/química , Ceras/química , Solventes/química , Cristalização , Géis/química , Óleo de Farelo de Arroz/química
7.
J Physiol Sci ; 73(1): 15, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37464272

RESUMO

We evaluated the reliability of a newly developed wearable ear canal thermometer based on three different experiments, in which ear canal and rectal temperature (Tear and Trec, respectively) were simultaneously monitored. In Experiment 1, participants sat at 28 °C and 50% relative humidity (RH), during which fanning or 41 °C lower legs water immersion was conducted. In Experiment 2, participants conducted a 70-min treadmill exercise (4 km/h, 0.5% slope) at 35 °C and 50% RH with intermittent fanning. In Experiment 3, participants completed a 20 min treadmill exercise (6 km/h, 5% slope) at 35 °C and 65% RH. Bland-Altman analysis for Tear and Trec showed the difference of - 0.2-0.3 °C and the limit of agreement of the mean ± 0.3-0.6 °C. The intraclass correlation coefficient was 0.44-0.83. The results may suggest that the ear canal thermometer is useful to assess core body temperature in sports and/or labor fields.


Assuntos
Temperatura Corporal , Dispositivos Eletrônicos Vestíveis , Humanos , Termômetros , Meato Acústico Externo , Reprodutibilidade dos Testes , Temperatura Baixa , Temperatura Alta
8.
Ecol Evol ; 13(11): e10615, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38034332

RESUMO

Over the years, theoreticians and empiricists working in a wide range of disciplines, including physiology, ethology, psychology, and behavioral ecology, have suggested a variety of reasons why individual differences in behavior might change over time, such that different individuals become more similar (convergence) or less similar (divergence) to one another. Virtually none of these investigators have suggested that convergence or divergence will continue forever, instead proposing that these patterns will be restricted to particular periods over the course of a longer study. However, to date, few empiricists have documented time-specific convergence or divergence, in part because the experimental designs and statistical methods suitable for describing these patterns are not widely known. Here, we begin by reviewing an array of influential hypotheses that predict convergence or divergence in individual differences over timescales ranging from minutes to years, and that suggest how and why such patterns are likely to change over time (e.g., divergence followed by maintenance). Then, we describe experimental designs and statistical methods that can be used to determine if (and when) individual differences converged, diverged, or were maintained at the same level at specific periods during a longitudinal study. Finally, we describe why the concepts described herein help explain the discrepancy between what theoreticians and empiricists mean when they describe the "emergence" of individual differences or personality, how they might be used to study situations in which convergence and divergence patterns alternate over time, and how they might be used to study time-specific changes in other attributes of behavior, including individual differences in intraindividual variability (predictability), or genotypic differences in behavior.

9.
J Hepatobiliary Pancreat Sci ; 30(5): 693-703, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36271512

RESUMO

BACKGROUND: The torque and fanning techniques allow for multiple areas within pancreatic lesions to be targeted using different maneuvers and can, hence, enhance diagnostic outcomes. We compared the diagnostic performance of endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) for pancreatic masses using the torque and fanning techniques. METHODS: This multicenter randomized trial enrolled a total of 160 consecutive patients who underwent EUS-FNB for solid pancreatic tumors using either the torque or fanning technique. Three passes were permitted for each lesion, and the technique sequence was randomly assigned as either torque first or fanning first with the standard technique as a reference. RESULTS: The median quality score of the histological samples was significantly higher in the torque and fanning group than in the standard group (p < .001). Furthermore, the torque technique provided improved sensitivity of 93.38% and accuracy of 94.30%. The standard technique provided diagnostic sensitivity of 68.84% and accuracy of 72.96%, while the fanning technique showed sensitivity of 91.85% and accuracy of 93.04%. CONCLUSIONS: The new torque technique enables the acquisition of better-quality samples and can potentially increase the diagnostic outcomes in the EUS-FNB of pancreatic solid masses, with the same recommendations as those for the fanning technique.


Assuntos
Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Neoplasias Pancreáticas , Humanos , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Torque , Pâncreas/diagnóstico por imagem , Neoplasias Pancreáticas/patologia , Biópsia Guiada por Imagem
10.
J Crohns Colitis ; 2020 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-32770194

RESUMO

Inflammatory bowel disease (IBD) is characterized by abnormal host-microbe interactions. Proinflammatory cytokine IFNγ and a novel TNF superfamily member, TL1A, have been implicated in epithelial barrier dysfunction. The divergent regulatory mechanisms of transcellular versus paracellular hyperpermeability remain poorly understood. Intestinal epithelia express two splice variants of long myosin light chain kinase (MLCK), of which the full-length MLCK1 differ from the shorter isoform MLCK2 by a Src kinase phosphorylation site. The aim was to investigate the roles of MLCK splice variants in gut barrier defects under proinflammatory stress. Upregulated expression of TL1A, IFNγ, and two MLCK variants was observed in human IBD biopsy specimens. The presence of intraepithelial bacteria preceded tight junction (TJ) damage in dextran sodium sulfate-treated and TL1A-transgenic mouse models. Lack of barrier defects was observed in long MLCK(-/-) mice. TL1A induced MLCK-dependent terminal web (TW) contraction, brush border fanning, and transepithelial bacterial internalization. The bacterial taxa identified in the inflamed colonocytes included Escherichia, Enterococcus, Staphylococcus,and Lactobacillus. Recombinant TL1A and IFNγ at low doses induced PI3K/Akt/MLCK2-dependent bacterial endocytosis, whereas high-dose IFNγ caused TJ opening via the iNOS/Src/MLCK1 axis. Bacterial internalization was recapitulated in MLCK-knockout cells individually expressing MLCK2 but not MLCK1. Immunostaining showed different subcellular sites of phosphorylated MLC localized to the TJ and TW in the MLCK1- and MLCK2-expressing cells, respectively. In conclusion, proinflammatory cytokines induced bacterial influx through transcellular and paracellular routes via divergent pathways orchestrated by distinct MLCK isoforms. Bacterial transcytosis induced by TL1A may be an alternative route causing symptom flares in IBD.

11.
World J Emerg Surg ; 14: 1, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30636969

RESUMO

Background: Point-of-Care Ultrasound (POCUS) is a useful diagnostic tool. Nevertheless, it needs proper training to reach its required level of competency. Educators who work in low-income countries find it difficult to purchase expensive training computer-based simulators. We aim in this communication to describe the methods to build up and use an efficient, simple, and cheap simulator which can be used for teaching POCUS globally. Methods: It took our group 2 years to develop the simulator to its current form. The required material for the simulator includes a Kunafa knife, a carton gift box and its cover and colored play dough. The Kunafa knife with its blade is an excellent simulator for the small print convex array probe (3-5 MHz) and its ultrasound sections. It is useful to teach two important principles. First, the three basic hand movements used to control the ultrasound probe (fanning, tilting, and shifting). Second, the thin blade of the knife (1 mm thick) simulates the shape of the two-dimensional ultrasound images. The play dough is used to simulate different organs to be cut in different directions like the aorta and inferior vena cava. Results: The simulator was used to teach 88 fifth year medical students during the period of November 2017 to November 2018 at the College of Medicine and Health Sciences, UAE University. The simulator was valid, simple, portable, and sustainable. The students greatly enjoyed its use. The cost of the simulator is less than 10 US dollars. Conclusions: Surgical educators who work in low-income countries are encouraged to develop their educational tools that are tailored to their own needs. Our simulator can help our colleagues who want to teach POCUS and cannot purchase expensive mannequins and computer-based simulators.


Assuntos
Pessoal de Saúde/educação , Treinamento por Simulação/normas , Estudantes de Medicina/estatística & dados numéricos , Ultrassonografia/métodos , Currículo/normas , Currículo/tendências , Educação de Graduação em Medicina/métodos , Educação de Graduação em Medicina/normas , Avaliação Educacional , Pessoal de Saúde/tendências , Humanos , Jogos e Brinquedos , Sistemas Automatizados de Assistência Junto ao Leito/normas , Sistemas Automatizados de Assistência Junto ao Leito/tendências , Treinamento por Simulação/métodos
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