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1.
PLoS One ; 19(2): e0289682, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38306340

RESUMO

The Cheilomenes sexmaculata (Fabricius) (Coleoptera: Coccinellidae), is one of the most beneficial and identifiable predators of numerous soft-bodied and sucking insect pests of several crops. Biological parameters and olfactory response of C. sexmaculata were investigated under laboratory conditions by providing three different aphid species i.e., mustard aphid (Lipaphis erysimi Kaltenbach), citrus black aphid (Toxoptera citricida Kirkaldy), and peach aphid (Diuraphis noxia Kurdjumov) as a food source. The developmental period of immature stages of C. sexmaculata was shorter on D. noxia as compared to other aphid species. The adult longevities were longer on D. noxia and T. citricida while shorter on L. erysimi. Female fecundity was highest on D. noxia while lowest on L. erysimi. Life table parameters i.e., intrinsic rate of increase (r), finite rate of increase (λ), net reproductive rate (Ro), and gross reproductive rate (GRR) were maximum on D. noxia while minimum on L. erysimi. The mean generation time C. sexmaculata was 20.90, 23.69, and 26.2 days on D. noxia, L. erysimi, T. and citricida, respectively. These findings were further confirmed from the olfactory experiment where D. noxia proved to be the most preferred prey. This study provides necessary information for mass-rearing of C. sexmaculata.


Assuntos
Afídeos , Besouros , Feminino , Animais , Besouros/fisiologia , Afídeos/fisiologia , Tábuas de Vida , Quimiotaxia , Produtos Agrícolas
2.
Heliyon ; 9(8): e18303, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37576316

RESUMO

The Zr2AC MAX phases are a family of ternary carbides ceramics that possess layered structures and exhibiting exceptional properties resulting from combining the most desirable features of metals and ceramics. In addition, the Zr2AC MAX-phases exhibit numerous physical and chemical properties due to their chemical and structural characteristics, a tendency for multiple basal dislocations and exhibiting mobility under ambient conditions. This review extensively analyzes the properties of the Zr2AC MAX phase, as they are closely linked to the exceptional and potential applications of the MAX phase. For the first time, the present study analyzed various properties of Zr2AC MAX phases, including structural, electronic, elastic, thermal, optical, self-healing, nuclear, oxidation, and corrosion characteristics. Furthermore, this review included experimental and theoretical work with comparison. It's found that the Zr2AC lattice parameters a and c are deviations theoretically from 0.1 to 2% and 0.15-2.87% compared with experimental work. Also, the Zr2AC MAX phases are metallic characters and the conductivity differs depending on the type of the Zr2AC(different A element) MAX phases. Its concluded that the Zr2AC MAX phases are stiff, isotropic elastic properties and high machinability with damage tolerance and hardness levels ranging from 3.5 to 13.02 Gpa. The Zr2AC MAX phases are also resistant to corrosion, thermal shock, and oxidation as well as lightweight. In addition, at elevated temperatures the transition from brittle to plastic behavior can be occurred in the Zr2AC MAX phase. The Zr2AC MAX phase's optical properties are anisotropic such as electrical conductivity and mechanical properties. This review study provides a comprehensive details assisting researches to deal with Zr2AC MAX phase potentially for different applications.

3.
Int J Biol Macromol ; 235: 123794, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-36828090

RESUMO

DNA methylation-mediated transcriptional regulation has been considered to significantly impact some steroidogenic enzyme genes expression. To uncover the roles of DNA methylation on the regulation of aromatase gene expression during gametogenesis in Misgurnus anguillicaudatus, the expression profiles and cellular localization of cyp19a1a and cyp19a1b were analyzed, and the landscape of DNA methylation dynamics was investigated. We found that cyp19a1a was predominantly expressed in granulosa cells of oocytes, while cyp19a1b expression was enriched in radial glial cells of the forebrain. In ovary, cyp19a1a was highly expressed until the vitellogenesis stage. The average methylation levels, especially for two CpG sites within the cAMP response element, were negatively correlated with cyp19a1a expression levels, indicating that methylation could regulate cyp19a1a transcriptional activity by modulating the binding efficiency of cAMP to its response elements. Compared with in ovary, cyp19a1a showed lower expression in testis but was hypermethylated. Cyp19a1b in female brain weakly expressed before the vitellogenesis stage, but significantly elevated at the maturation stage. In both sexes, it maintained high methylation levels in brain despite the obvious fluctuation of the cyp19a1b expression. This study revealed that DNA methylation plays a key role in establishing cyp19a1a spatiotemporal expression patterns and thus mediates gonadal development in teleosts.


Assuntos
Cipriniformes , Metilação de DNA , Masculino , Animais , Feminino , Ovário/metabolismo , Testículo/metabolismo , Oócitos/metabolismo , Cipriniformes/genética
4.
Turk J Chem ; 47(4): 763-781, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38174058

RESUMO

A unique Zr2Al-GNS MAX phase ceramic supported nanographene sheet was prepared using a cost-effective pressureless sintering technique under relatively low temperature. An experimental investigation was conducted to explore the lattice parameters using different temperatures, such as 1000, 1150, and 1300 °C. To characterize the crystal structure of the MAX phase ceramic, X-ray diffraction, field emission scanning electron microscopy imaging, energy-dispersive X-ray spectroscopy (EDX), high-resolution transmission electron microscopy (HRTEM), and selected area diffraction (SAED) were utilized. The results revealed that the pressureless sintering technique was successfully utilized to synthesize the Zr2Al-GNS MAX phase ceramic under 1150 °C with a low impurity ratio of secondary phases such as Zr3AL2, Zr3AL5, and ZrC components. The high percentage of the Zr2Al-GNS MAX phase ceramic was obtained at 49.0% at 1150 °C compared with different temperatures. The BET surface area (SBET), pore volume, and pore size were also investigated. The SBET of the prepared Zr2Al-GNS MAX phase was increased to 30% using graphene nanosheet, while the porosity was highly decreased to 8% from its original value. The electrical properties were also studied in this research for potential applications, such as the absolute value of impedance (Z), absolute value of admittance (Y), induction (L), capacitance (C), resistance (R), conductance (G), susceptibility (B), and phase angle (Ï´). It was found that the capacitance and the phase angle were improved using the prepared Zr2Al-GNS MAX phase ceramic, depending on the frequencies. The results presented here may facilitate the improvements in the features of the MAX phase type of Zr2Al-GNS-enhanced one-layer nanographene sheet for electrical applications ceramic.

5.
Turk J Chem ; 46(3): 704-720, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37720600

RESUMO

A new nanocomposite superhydrophobic of the RTV (room temperature vulcanized) silicon rubber reinforced with a different percentage of nanosilica was prepared by a two-stage sol-gel route to obtain a superhydrophobic surface coating on high voltage glass insulator, preventing the dust-water droplet from adhering to its surface. The cold spraying technique was utilized to build up a thin nanocomposite superhydrophobic layer on the glass insulator containing different percentages of the nanosilica particles, such as 23 wt %, 33 wt %, and 44 wt % with RTV silicon substrate. The synthesized nanocomposite was analyzed using the contact angle, roughness, adhesion, hardness, and dielectric strength tests. Moreover, the prepared RTV silicon rubber/nanosilica superhydrophobic nanocomposite layer was characterized using the field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and the particle size analysis test. Based on the results, the nanosilica particles were well-incorporated into the RTV silicon rubber, obtaining an excellent homogenous distribution thin layer on its surface, supporting its capability to be a superior superhydrophobic surface. The results reveal that the RTV silicon rubber/33wt % nanosilica was the best as a superhydrophobic behavior with a contact angle reaching higher than 158° ± 3; also, a significant change in the dielectric strength was obtained to be 25.5 kV (using a speed voltage of 5.0 kV/s). Importantly, the flashover test was also conducted, and it was found that there was a significant change in the leak current between the coated and uncoated samples. The leak current of the coated sample with a superhydrophobic nanocomposite was reduced to 2.5 mA, while the uncoated sample became 3.2 mA using a voltage load value of 60 kV. The results presented here may improve the nanocomposite material as an antiweathering superhydrophobic thin layer supported by the prepared nano-SiO2 particles against the dust-water droplets which may be adhesive to the high voltage glass insulator.

6.
PLoS One ; 15(9): e0228367, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32976485

RESUMO

The Zigzag ladybird beetle, Cheilomenes sexmaculata (Fabricius) (Coleoptera: Coccinellidae), is a biological control agent that feeds on a variety of aphid species. Life table and predation data of C. sexmaculata were collected under laboratory conditions at 25±2°C, 60±5% RH and L14: D10 h in connection with feeding on four different aphid species; Lipaphis erysimi (Kaltenbach), Myzus persicae (Sulzer), Aphis nerii (Boyer de Fonscolombe) and Diuraphis noxia (Mordvilko). Larval development of C. sexmaculata was long when fed on M. persicae (12.18 days) and shorter on D. noxia (10.64 days). The male's lifespan was longer on M. persicae (26.70 days) and shorter on L. erysimi (23.67 days). Fecundity was maximum when the beetle was fed D. noxia (316.8 eggs/female) and minimum on M. persicae (199.1 eggs/female). Net reproductive rate, intrinsic rate of increase and finite rate of increase were highest on D. noxia with values of 158.4 (offspring individual-1), 0.22 d-1, and 1.24 d-1, respectively whereas the respective parameters were lowest on L. erysimi (99.5 offspring individual-1, 0.19 d-1, and 1.20 d-1, respectively). However, the mean of the generation (T) was shorter on A. nerii (22.48 d-1) and longer on M. persicae (24.68 d-1). Based on life table parameters obtained under laboratory conditions, the most appropriate host of C. sexmaculata was D. noxia. This study should help us to improve mass rearing and use of C. sexmaculata in the biological control of aphids on field and horticultural crops.


Assuntos
Afídeos/parasitologia , Besouros/fisiologia , Controle Biológico de Vetores/métodos , Comportamento Predatório/fisiologia , Animais , Afídeos/fisiologia , Feminino , Fertilidade/fisiologia , Larva , Tábuas de Vida , Longevidade/fisiologia , Masculino , Paquistão
7.
Springerplus ; 5: 530, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27186494

RESUMO

OBJECTIVES: The aim of this study is to compare two methods of internal fixations of fractured medial malleolus which are simple screw fixation and tension band wiring. PATIENTS AND METHODS: Over 5 years we grouped 20 patients with fractured medial malleolus into two groups of operative treatments, group1 treated by malleolar screw fixation and group2 by tension band wiring. The patients were with same age group, gender, fracture type, and etiology. We use statistical analysis for make a comparative study between the two ways of surgical treatment. RESULTS: The mean time for radiologic bone union was 11.8 weeks in group1 patients and 9.4 weeks in group2 patients (P = 0.03). No patients had any sign of fixation failure or Kirschner wires migration. According to the modified ankle scoring system of Olerud and Molander, excellent and good results were achieved in 80 % in group1 patients and 90 % in group2 patients (P = 0.049). CONCLUSIONS: Tension-band wiring may be better treatment option for internal fixation of medial malleolar fractures than screw fixation. RECOMMENDATIONS: From these findings we recommend a further randomized clinical trial of larger number of cases and longer follow-up duration in order to regard tension-band wiring a better operative option for fixation of medial malleolar fractures.

8.
Fish Physiol Biochem ; 35(3): 435-41, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18998231

RESUMO

Haematological and serum biochemistry parameters were studied and compared between cultured and wild ecotypes of Dojo loach Misgurnus anguillicaudatus during the prime fishing season, i.e. May-August. Data were analysed for the impact of feeding regime and other ecological conditions on the physiology of fish. The results revealed that haemoglobin, cholesterol, total protein, creatinine and uric acid levels in the two ecotypes were significantly different (n = 56, df = 54, P < 0.05). In addition, red blood cell, glucose, triglyceride and urea nitrogen levels were significantly higher in cultured individuals (n = 56, df = 54, P < 0.01) than in their wild counterparts. In contrast, the white blood cell level in cultured fish was significantly (n = 56, df = 54, P < 0.01) lower than that in the wild ones. These differences can be attributed to the physiological acclimatization of the fish to their living conditions and feeding regime, which influences the energy metabolism and, consequently, the health of the fish.


Assuntos
Aclimatação/fisiologia , Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Animais Domésticos/sangue , Animais Selvagens/sangue , Cipriniformes/sangue , Animais , Animais Domésticos/fisiologia , Animais Selvagens/fisiologia , Análise Química do Sangue , China , Cipriniformes/fisiologia , Estatísticas não Paramétricas
9.
Artigo em Inglês | MEDLINE | ID: mdl-17466553

RESUMO

The purpose of this study was to determine whether diploid, triploid and tetraploid loach (Misgurnus anguillicaudatus) differed in terms of their main haematological and physiological characteristics. Diploid and tetraploid fish were produced by crossing of natural diploids (2n x 2n) and natural tetraploids (4n x 4n), respectively. Triploid fish were produced by hybridization between diploid males and tetraploid females. The blood cells were significantly larger in polyploids, and the volumetric ratios of erythrocytes and leucocytes (thrombocyte and neutrophil) in tetraploids, triploids and diploids were consistent with the ploidy level ratio of 4:3:2. No significant differences were observed in haematocrit among polyploids. The erythrocyte count decreased with increased ploidy level, while total haemoglobin, mean cell volume, mean cellular haemoglobin content, and mean cell haemoglobin concentration all increased with increase in ploidy level. Erythrocyte osmotic brittleness declined in polyploids so that polyploid erythrocytes were more resistant to osmotic stress than diploid ones. Overall, loach with higher ploidy levels showed evidence of some advantages in haematological characteristics.


Assuntos
Cipriniformes/sangue , Cipriniformes/genética , Diploide , Poliploidia , Animais , Contagem de Células Sanguíneas , Plaquetas/citologia , Tamanho Celular , DNA , Eritrócitos/citologia , Feminino , Citometria de Fluxo , Granulócitos/citologia , Hematócrito , Hemoglobinas/análise , Linfócitos/citologia , Masculino , Monócitos/citologia
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