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1.
Sci Rep ; 13(1): 9660, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37316564

RESUMO

Two dimensional wavy walls rectangular cavity with inclined magnetohydrodynamic has been examined in mixed convection configurations. Triple fins arranged in the upwards ladder were filled within alumina nanoliquid in the cavity. Vertical sinusoidal walls were heated, and the other side was kept cold while both horizontal walls were kept adiabatic. All walls were motionless except the top cavity that was driven to the right. The diversified range of control parameter in Richardson number, Hartmann number, number of undulations, length of the cavity has been performed in this study. The analysis was simulated using finite element method by employing the governing equation formula, and the results were delineated in the form of streamlines, isotherms, heatlines, and comparisons on several relationships between the local velocity in the y-axis line of 0.6, local and average Nusselt number along the heated surface and dimensionless average temperature. The findings revealed that high concentration nanofluids boost the rate of heat transfer without the need to apply any magnetic field. Results found that the best heat mechanisms are natural convection with significant-high Richardson number as well as constructing two waves on the vertical walls in the cavity.

2.
J Affect Disord ; 323: 506-513, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36462610

RESUMO

BACKGROUND: Bipolar disorder (BD) is a psychiatric disorder characterized by episodes of depression and mania, associated with impaired emotion processing. Several functional MRI (fMRI) studies have been used to investigate the structural and functional alteration in BD. Here, we aim to investigate the current fMRI findings of brain activation during emotion-regulation tasks between BD patients and healthy controls (HC). METHODS: A systematic search through PubMed database for fMRI studies on bipolar patients and HC yielded 685 studies. We performed an activation likelihood estimation (ALE) on 21 studies for emotion regulation in BD patients and HC. Furthermore, we performed subgroup analyses for task performances in response time and accuracy between bipolar patients and HC. RESULTS: The total sample included 21 fMRI studies, comprising 543 BD patients, compared to 565 HC. ALE maps for emotion-related tasks showed hyperactivation in BD patients in the caudate, amygdala, precentral gyrus, middle frontal gyri, and sub-gyrus. Whereas hypoactivation was seen in the inferior frontal gyrus and anterior cingulate gyrus. LIMITATIONS: We could not apply a correction for p-value thresholds, as it needs large number of foci. Second, functional abnormalities were investigated for adult BD patients only, as BD patients have functional differences correlated with age. CONCLUSIONS: Our results showed that limbic and cortical regions can represent a potential biomarker for the diagnosis and management of BD, by showing clustered brain regions of abnormal patterns of increased activation between BD patients and HC.


Assuntos
Transtorno Bipolar , Regulação Emocional , Adulto , Humanos , Transtorno Bipolar/diagnóstico , Encéfalo , Tonsila do Cerebelo/diagnóstico por imagem , Neuroimagem , Emoções/fisiologia , Imageamento por Ressonância Magnética/métodos
3.
Medicine (Baltimore) ; 101(43): e31206, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36316871

RESUMO

BACKGROUND: Migraine is a primary headache disorder that causes debilitating throbbing pain. Several functional MRI (fMRI) and voxel-based morphometry (VBM) studies have been used to investigate the structural and functional alteration in migraine. Here, we aim to study the converged brain regions of functional and structural abnormalities in gray matter volume (GMV) associated with pain processing and management in migraineurs and healthy controls (HC). METHODS: A systematic search through PubMed and Sleuth was carried out for peer-reviewed functional and structural neuroimaging studies on migraine patients and HC yielded a total of 1136 studies. We performed an activation likelihood estimation (ALE) meta-analysis on VBM and pain stimulation task-based fMRI studies to investigate the converged areas of GMV and functional abnormalities between migraineurs and HC. We performed two subgroup analyses between migraine with aura (MwA) and migraine without aura (MwoA) relative to HC, and between chronic migraine (CM) and episodic migraine (EM) compared to HC. RESULTS: The total sample included 16 fMRI and 22 VBM studies, consisting of 1295 migraine patients, compared to 995 HC. In fMRI analysis, ALE maps for pain stimulation tasks revealed hyperactivation in migraineurs in the substantia nigra compared to HC, whereas hypoactivation was seen in the cerebellum. For the VBM analysis, ALE clusters of increased GMV in migraineurs were observed in the parahippocampus and putamen nucleus. Whereas clusters of reduced GMV in migraineurs were seen in the frontal gyri. Compared to HC, MwoA patients showed a GMV reduction in the insula, and anterior cingulate, whereas MwA patients showed GMV reduction in the cerebellum, cingulate gyrus, and insula. CM patients showed decreased GMV in the precentral gyrus, whereas EM patients showed decreased GMV in the parahippocampus, and inferior frontal gyrus when compared to HC. CONCLUSIONS: Our findings represent a potential biomarker for the diagnosis and management of migraine, by showing clustered brain regions of abnormal patterns of activation and GMV changes between migraineurs and HC which might be associated with hyposensitivity to pain in migraineurs. Further studies are required to determine disease progression or therapeutic interventions' effect on migraine.


Assuntos
Enxaqueca com Aura , Enxaqueca sem Aura , Humanos , Funções Verossimilhança , Substância Cinzenta , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Dor/etiologia
4.
Entropy (Basel) ; 23(10)2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34681961

RESUMO

The flow and heat transfer fields from a nanofluid within a horizontal annulus partly saturated with a porous region are examined by the Galerkin weighted residual finite element technique scheme. The inner and the outer circular boundaries have hot and cold temperatures, respectively. Impacts of the wide ranges of the Darcy number, porosity, dimensionless length of the porous layer, and nanoparticle volume fractions on the streamlines, isotherms, and isentropic distributions are investigated. The primary outcomes revealed that the stream function value is powered by increasing the Darcy parameter and porosity and reduced by growing the porous region's area. The Bejan number and the average temperature are reduced by the increase in Da, porosity ε, and nanoparticles volume fractions ϕ. The heat transfer through the nanofluid-porous layer was determined to be the best toward high rates of Darcy number, porosity, and volume fraction of nanofluid. Further, the local velocity and local temperature in the interface surface between nanofluid-porous layers obtain high values at the smallest area from the porous region (D=0.4), and in contrast, the local heat transfer takes the lower value.

5.
Sci Rep ; 11(1): 14700, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34282226

RESUMO

The entropy production and mixed convection within a trapezoidal nanofluid-filled cavity having a localised solid cylinder is numerically examined using the finite element technique. The top horizontal surface moving at a uniform velocity is kept at a cold temperature, while the bottom horizontal surface is thermally activated. The remaining surfaces are maintained adiabatic. Water-based nanofluids ([Formula: see text] nanoparticles) are used in this study, and the Boussinesq approximation applies. The influence of the Reynolds number, Richardson number, nanoparticles volume fraction, dimensionless radius and location of the solid cylinder on the streamlines, isotherms and isentropic are examined. The results show that the solid cylinder's size and location are significant control parameters for optimising the heat transfer and the Bejan number inside the trapezoidal cavity. Furthermore, the maximum average Nusselt numbers are obtained for high R values, where the average Nusselt number is increased by 30% when R is raised from 0 to 0.25.

6.
Nanomaterials (Basel) ; 11(5)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068022

RESUMO

A numerical study is presented for the thermo-free convection inside a cavity with vertical corrugated walls consisting of a solid part of fixed thickness, a part of porous media filled with a nanofluid, and a third part filled with a nanofluid. Alumina nanoparticle water-based nanofluid is used as a working fluid. The cavity's wavy vertical surfaces are subjected to various temperature values, hot to the left and cold to the right. In order to generate a free-convective flow, the horizontal walls are kept adiabatic. For the porous medium, the Local Thermal Non-Equilibrium (LTNE) model is used. The method of solving the problem's governing equations is the Galerkin weighted residual finite elements method. The results report the impact of the active parameters on the thermo-free convective flow and heat transfer features. The obtained results show that the high Darcy number and the porous media's low modified thermal conductivity ratio have important roles for the local thermal non-equilibrium effects. The heat transfer rates through the nanofluid and solid phases are found to be better for high values of the undulation amplitude, the Darcy number, and the volume fraction of the nanofluid, while a limit in the increase of heat transfer rate through the solid phase with the modified thermal ratio is found, particularly for high values of porosity. Furthermore, as the porosity rises, the nanofluid and solid phases' heat transfer rates decline for low Darcy numbers and increase for high Darcy numbers.

7.
J Adv Res ; 30: 63-74, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34026287

RESUMO

INTRODUCTION: Mixed convection flow and heat transfer within various cavities including lid-driven walls has many engineering applications. Investigation of such a problem is important in enhancing the performance of the cooling of electric, electronic and nuclear devices and controlling the fluid flow and heat exchange of the solar thermal operations and thermal storage. OBJECTIVES: The main aim of this fundamental investigation is to examine the influence of a two-phase hybrid nanofluid approach on mixed convection characteristics including the consequences of varying Richardson number, number of oscillations, nanoparticle volume fraction, and dimensionless length and dimensionless position of the solid obstacle. METHODS: The migration of composite hybrid nanoparticles due to the nano-scale forces of the Brownian motion and thermophoresis was taken into account. There is an inner block near the middle of the enclosure, which contributes toward the flow, heat, and mass transfer. The top lid cover wall of the enclosure is allowed to move which induces a mixed convection flow. The impact of the migration of hybrid nanoparticles with regard to heat transfer is also conveyed in the conservation of energy. The governing equations are molded into the non-dimensional pattern and then explained using the finite element technique. The effect of various non-dimensional parameters such as the volume fraction of nanoparticles, the wave number of walls, and the Richardson number on the heat transfer and the concentration distribution of nanoparticles are examined. Various case studies for Al2O3-Cu/water hybrid nanofluids are performed. RESULTS: The results reveal that the temperature gradient could induce a notable concentration variation in the enclosure. CONCLUSION: The location of the solid block and undulation of surfaces are valuable in the control of the heat transfer and the concentration distribution of the composite nanoparticles.

8.
Entropy (Basel) ; 22(6)2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-33286378

RESUMO

The current study investigates the 2D entropy production and the mixed convection inside a wavy-walled chamber containing a rotating cylinder and a heat source. The heat source of finite-length h is placed in the middle of the left vertical surface in which its temperature is fixed at T h . The temperature of the right vertical surface, however, is maintained at lower temperature T c . The remaining parts of the left surface and the wavy horizontal surfaces are perfectly insulated. The governing equations and the complex boundary conditions are non-dimensionalized and solved using the weighted residual finite element method, in particular, the Galerkin method. Various active parameters are considered, i.e., Rayleigh number R a = 10 3 and 10 5 , number of oscillations: 1 ≤ N ≤ 4 , angular rotational velocity: - 1000 ≤ Ω ≤ 1000 , and heat source length: 0 . 2 ≤ H ≤ 0 . 8 . A mesh independence test is carried out and the result is validated against the benchmark solution. Results such as stream function, isotherms and entropy lines are plotted and we found that fluid flow can be controlled by manipulating the rotating velocity of the circular cylinder. For all the considered oscillation numbers, the Bejan number is the highest for the case involving a nearly stationary inner cylinder.

9.
Sci Rep ; 10(1): 18048, 2020 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-33093608

RESUMO

This study investigates thermal natural convective heat transfer in a nanofluid filled-non-Darcian porous and wavy-walled domain under the local thermal non-equilibrium condition. The considered cavity has corrugated and cold vertical walls and insulated horizontal walls except the heated part positioned at the bottom wall. The transport equations in their non-dimensional model are numerically solved based on the Galerkin finite-element discretization technique. The dimensionless governing parameters of the present work are the nanoparticle in volume concentration, the Darcy number, number of undulations, modified heat conductivity ratio, dimensionless heated part length, and location. Comparisons with other published theoretical and experimental results show good agreement with the present outcomes. The findings indicate that the heater length, its position, and the waves number on the side vertical walls as well as the nanoparticles concentration can be the control parameters for free convective motion and heat transport within the wavy cavity.

10.
Nanomaterials (Basel) ; 10(6)2020 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-32526982

RESUMO

The mixed convection two-phase flow and heat transfer of nanofluids were addressed within a wavy wall enclosure containing a solid rotating cylinder. The annulus area between the cylinder and the enclosure was filled with water-alumina nanofluid. Buongiorno's model was applied to assess the local distribution of nanoparticles in the host fluid. The governing equations for the mass conservation of nanofluid, nanoparticles, and energy conservation in the nanofluid and the rotating cylinder were carried out and converted to a non-dimensional pattern. The finite element technique was utilized for solving the equations numerically. The influence of the undulations, Richardson number, the volume fraction of nanoparticles, rotation direction, and the size of the rotating cylinder were examined on the streamlines, heat transfer rate, and the distribution of nanoparticles. The Brownian motion and thermophoresis forces induced a notable distribution of nanoparticles in the enclosure. The best heat transfer rate was observed for 3% volume fraction of alumina nanoparticles. The optimum number of undulations for the best heat transfer rate depends on the rotation direction of the cylinder. In the case of counterclockwise rotation of the cylinder, a single undulation leads to the best heat transfer rate for nanoparticles volume fraction about 3%. The increase of undulations number traps more nanoparticles near the wavy surface.

11.
Adv Bioinformatics ; 2020: 3407907, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32395129

RESUMO

Autism spectrum disorder (ASD) is an early developmental disorder characterized by mutation of enculturation associated with attention deficit disorder in the visual perception of emotional expressions. An estimated one in more than 100 people has autism. Autism affects almost four times as many boys than girls. Data analysis and classification of ASD is still challenging due to unsolved issues arising from many severity levels and range of signs and symptoms. To understanding the functions which involved in autism, neuroscience technology analyzed responses to stimuli of autistic audio and video. The study focuses on analyzing the data set of adults and children with ASD using practical component analysis method. To satisfy this aim, the proposed method consists of three main stages including: (1) data set preparation, (2) Data analysis, and (3) Unsupervised Classification. The experimental results were performed to classify adults and children with ASD. The classification results in adults give a sensitivity of 78.6% and specificity of 82.47%, while the classification results in children give a sensitivity of 87.5% and specificity of 95.7%.

12.
Animal ; 12(12): 2587-2597, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29679989

RESUMO

In pikeperch, Sander lucioperca, aquaculture hormonal treatment is usually applied to synchronize ovulation. However, the effect of dopamine (DA) receptor antagonists, in particular those blocking the D1 DA receptors, remains unknown. Thus, the aim of the present study was to investigate and compare the effects of D1 and D2 DA receptor antagonists on the sex-steroid production and reproductive performance of the species. Two experiments were performed during which mature pikeperch females were injected with different molecules: NaCl 0.9% (negative control) or human chorionic gonadotropin 500 IU/kg (positive control) in both experiments, metoclopramide (a D2 receptor antagonist; 4 mg/kg or 20 mg/kg) or SCH23390 (a D1 receptor antagonist; 0.8 mg/kg or 4 mg/kg) alone (experiment 1) or in combination with a salmon gonadotropin-releasing hormone analogue (sGnRHa at 25 µg/kg; experiment 2). In experiment 2, fish were also injected with sGnRHa (25 µg/kg) as positive control. Samplings of oocytes and blood were performed on the day of injection and after 24 h (both experiments), after 48 h (experiment 2) and at the time of ovulation (both experiments). In non-ovulating fish, samplings were performed 7 days (experiment 1) or 14 days (experiment 2) after injection. In experiment 2, various zootechnical parameters of fertilized eggs were recorded (survival, hatching and malformation rates). The two antagonists alone were ineffective in inducing the final stages and regulating sex-steroid (testosterone, 11 ketotestosterone, 17ß estradiol and 17,20ß-dihydroxy-4-pregnen-3-one) production. When administered with sGnRHa, both SCH23390 and metoclopramide induced the final stages. However, only SCH23390 stimulated testosterone (4 mg/kg) and 17ß estradiol (0.8 mg/kg) production compared with sGnRHa alone. None of the treatments affected the survival, hatching or malformation rates. This is the first report suggesting that in pikeperch the D1, but not the D2, DA receptor antagonist would be involved in the testosterone and 17ß estradiol production as a potentiator of the sGnRHa effect.


Assuntos
Gametogênese/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/análogos & derivados , Perciformes/fisiologia , Receptores Dopaminérgicos/metabolismo , Reprodução/efeitos dos fármacos , Esteroides/metabolismo , Animais , Benzazepinas/administração & dosagem , Gonadotropina Coriônica/administração & dosagem , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Metoclopramida/administração & dosagem , Oócitos/efeitos dos fármacos , Ovulação/efeitos dos fármacos
13.
Entropy (Basel) ; 20(5)2018 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-33265426

RESUMO

The problem of entropy generation analysis and natural convection in a nanofluid square cavity with a concentric solid insert and different temperature distributions is studied numerically by the finite difference method. An isothermal heater is placed on the bottom wall while isothermal cold sources are distributed along the top and side walls of the square cavity. The remainder of these walls are kept adiabatic. Water-based nanofluids with Al 2 O 3 nanoparticles are chosen for the investigation. The governing dimensionless parameters of this study are the nanoparticles volume fraction ( 0 ≤ ϕ ≤ 0.09 ), Rayleigh number ( 10 3 ≤ R a ≤ 10 6 ) , thermal conductivity ratio ( 0.44 ≤ K r ≤ 23.8 ) and length of the inner solid ( 0 ≤ D ≤ 0.7 ). Comparisons with previously experimental and numerical published works verify a very good agreement with the proposed numerical method. Numerical results are presented graphically in the form of streamlines, isotherms and local entropy generation as well as the local and average Nusselt numbers. The obtained results indicate that the thermal conductivity ratio and the inner solid size are excellent control parameters for an optimization of heat transfer and Bejan number within the fully heated and partially cooled square cavity.

14.
Entropy (Basel) ; 20(9)2018 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-33265753

RESUMO

This numerical study considers the mixed convection and the inherent entropy generated in Al 2 O 3 -water nanofluid filling a cavity containing a rotating conductive cylinder. The vertical walls of the cavity are wavy and are cooled isothermally. The horizontal walls are thermally insulated, except for a heat source segment located at the bottom wall. The dimensionless governing equations subject to the selected boundary conditions are solved numerically using the Galerkin finite-element method. The study is accomplished by inspecting different ranges of the physical and geometrical parameters, namely, the Rayleigh number ( 10 3 ≤ R a ≤ 10 6 ), angular rotational velocity ( 0 ≤ Ω ≤ 750 ), number of undulations ( 0 ≤ N ≤ 4 ), volume fraction of Al 2 O 3 nanoparticles ( 0 ≤ ϕ ≤ 0.04 ), and the length of the heat source ( 0.2 ≤ H ≤ 0.8 ) . The results show that the rotation of the cylinder boosts the rate of heat exchange when the Rayleigh number is less than 5 × 10 5 . The number of undulations affects the average Nusselt number for a still cylinder. The rate of heat exchange increases with the volume fraction of the Al 2 O 3 nanoparticles and the length of the heater segment.

15.
Fish Physiol Biochem ; 44(1): 301-310, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29103172

RESUMO

For most temperate and arctic fish species, photoperiod is the key abiotic factor determining the onset of the reproductive cycle, and, for many species, constant long photoperiod seems to have an inhibitory effect. Yet, there is no knowledge about the effect of photoperiod on the onset of the reproductive cycle in northern pike males. The aim of this work was to investigate the potential inhibitory effect of constant long photoperiod on pike males. Batches of fish were reared in triplicate under natural simulated photoperiod (NSP) or constant long photoperiod (CP; 16L:8D) from 14 October 2013 to 14 March 2014. Fish were sampled three times (at the beginning of the photoperiod decrease, at the beginning of the temperature decrease and at the end of the temperature decrease). Morphological parameters, sexual steroid levels and spermatogenetic stages were investigated. Our results showed that CP partially inhibited gonadal development (gonado-somatic index or GSI, %; 2.5% under NSP and 1.2% under CP at day 152), spermatic development (96.2% of spermatozoa under NSP and 69.3% under CP at day 152) and the plasmatic levels of testosterone (7.20 ng/mL under NSP and 2.37 ng/mL under CP at day 152). In conclusion, photoperiod may be one of the determinant factors that control the onset of the reproductive cycle in pike males, but temperature and endogenous rhythms also need to be investigated.


Assuntos
Esocidae/fisiologia , Fotoperíodo , Espermatogênese/fisiologia , Testosterona/sangue , Animais , Esocidae/sangue , Masculino , Reprodução/fisiologia , Estações do Ano , Testículo/fisiologia , Testosterona/análogos & derivados
18.
Sensors (Basel) ; 16(6)2016 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-27338402

RESUMO

The safety of the driving experience and manoeuvrability of a vehicle can be improved by detecting the strain in tyres. To measure strain accurately in rubber, the strain sensor needs to be flexible so that it does not deform the medium that it is measuring. In this work, a novel flexible bond wire capacitive strain sensor for measuring the strain in tyres is developed, fabricated and calibrated. An array of 25 micron diameter wire bonds in an approximately 8 mm × 8 mm area is built to create an interdigitated structure, which consists of 50 wire loops resulting in 49 capacitor pairs in parallel. Laser machining was used to pattern copper on a flexible printed circuit board PCB to make the bond pads for the wire attachment. The wire array was finally packaged and embedded in polydimethylsiloxane (PDMS), which acts as the structural material that is strained. The capacitance of the device is in a linear like relationship with respect to the strain, which can measure the strain up to at least ±60,000 micro-strain (±6%) with a resolution of ~132 micro-strain (0.013%). In-tyre testing under static loading has shown the ability of the sensor to measure large tyre strains. The technology used for sensor fabrication lends itself to mass production and so the design is considered to be consistent with low cost commercialisable strain sensing technology.

19.
Arch Pediatr ; 23(4): 373-7, 2016 Apr.
Artigo em Francês | MEDLINE | ID: mdl-26830955

RESUMO

Primary hyperparathyroidism, widely prevalent in women after menopause, remains rare in children and adolescents. Sporadic forms are the most frequent. Clinical manifestations are general, renal, gastrointestinal, cardiac, or bony. Diagnosis is biological and radiological. The imaging modalities allow assessment of the disease impact and identification of the parathyroid adenoma.


Assuntos
Adenoma/diagnóstico por imagem , Fraturas Espontâneas/etiologia , Hiperparatireoidismo Primário/etiologia , Vértebras Lombares/lesões , Neoplasias das Paratireoides/diagnóstico por imagem , Fraturas da Coluna Vertebral/etiologia , Adenoma/complicações , Adolescente , Feminino , Humanos , Hiperparatireoidismo Primário/diagnóstico , Neoplasias das Paratireoides/complicações
20.
Fish Physiol Biochem ; 41(2): 345-56, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25233876

RESUMO

The effect of a constant photoperiod on the inhibition of male and female reproductive cycles was studied in pikeperch Sander lucioperca. Over a 153-day period, batches of pikeperch (2 years, 950 g) breeders were kept under either under natural or artificial photoperiod conditions (24L:0D) (30-35 fish/tank, triplicate) and sampled in late June (start of the photoperiod decrease in natural conditions), late August (start of temperature decrease) and late November (exogenous vitellogenesis) (7-10 fish/tank/sampling date). Morphological parameters, sexual steroids, alkaline-labile phosphate (µg/mL) levels and gamete developmental stages were investigated. Gonado-somatic index (%), developmental stages and sexual steroid levels (17ß-estradiol, testosterone and 11-ketotestosterone, ng/mL) in both sexes and oocyte diameter (µm) and plasma alkaline-labile phosphate (µg/mL) in females were lower in response to a continuous lighting (24L:0D). In both sexes, continuous lighting applied in June for 153 days totally inhibited or delayed the onset of the reproductive cycle. In conclusion, photoperiod manipulation can be used to delay the pikeperch reproductive cycle, even if temperature decreases. This is the first report of the inhibitory effect of photoperiod on the onset of the reproductive cycle in pikeperch.


Assuntos
Aquicultura/métodos , Luz , Percas/crescimento & desenvolvimento , Fotoperíodo , Reprodução/efeitos da radiação , Animais , Feminino , Hormônios Esteroides Gonadais/metabolismo , Gônadas/efeitos dos fármacos , Masculino , Fosfatos/metabolismo
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