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The thermal treatment method was employed to achieve higher homogeneity of calcium ferrite (CaFe2O4) and Poly (vinyl alcohol) (PVA) nanocomposites. The influences of phase transformation on physical and biological properties of calcined specimens were investigated by various experimental techniques including X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), high resolution Field emission scanning electron microscope (FESEM) and Fourier transform infrared spectroscopy (FT-IR). Heat treatment was conducted at temperatures between 723 and 923 K, so that a phase transformation occurred from cubic to orthorhombic spinel structure at 923 K. The chemical analysis of the PVA/CaFe2O4 nanocomposite was performed by energy dispersion X-ray analysis (EDXA), demonstrated the PVA/CaFe2O4 nanocomposites contained the elements of C, Ca, Fe, and O. The formed nanocomposites exhibited ferromagnetic behaviors which were confirmed by using a vibrating sample magnetometer (VSM). The calcined specimens were carried out to an antimicrobial or antifungal test. 相似文献
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o-Nitrophenol, released from o-nitrophenyl-beta-D-galactopyranose as catalyzed by beta-galactosidase, a tetramer of Escherichia coli, has been exploited for the detection of E. coli contamination in foodstuffs. This reaction was detected using a boron doped diamond electrode poised at +0.93 V, without any surface modification. The enzyme was effectively induced by isopropyl-beta-D-thiogalacto-pyranoside with the maximum enzyme activity observed with sodium dodecyl sulfate at 50 degrees C. A biphasic calibration plot was observed: 4 x 10(4) to 2 x 10(5) cells/mL and 2 x 10(5) to 6 x 10(6) cells/mL for the first and second region, respectively. The detection limit was 4 x 10(4) cells/mL with a total analysis time of <1.5 h. Electrode fouling was easily overcome by approximately 40 rapid CV scans, and the method was applicable for detecting E. coli in artificially spiked samples of beef, pork, chicken, milk, and tap water. 相似文献
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Sohani NZ Shishehbor P Kocheili F 《Pakistan journal of biological sciences: PJBS》2008,11(7):1015-1020
Laboratory experiments were conducted to measure the functional and numerical responses of Eretmocerus mundus Mercet parasitizing cotton whitefly, Bemisia tabaci Gennadius. Parasitoids were isolated singly for 24 h in 5 cm petri dishes with either 5, 10, 20, 40, 60 or 100 second nymphal stages of B. tabaci. Results showed a typical type II functional response, with up to 43.2 hosts attacked when 100 hosts were provided. The rate of attack and handling time were 0.0465 and 0.3341 days, respectively. At above mentioned densities, the parasitoids lived an average of approximately 4 days. At host densities of < or =20 host/day, the total number of eggs laid was limited by the number of hosts available. Total fecundity was highest with an average of 196 eggs/female at density 100. 相似文献
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Ali Momenpour Ali Imani Davod Bakhshi Ehsan Akbarpour 《International Journal of Fruit Science》2018,18(4):410-435
ABSTRACTIn order to evaluate the tolerance of some almond genotypes to salinity, a factorial experiment was carried out based on completely randomized design (CRD), with two factors: genotypes in 11 levels (Tuono, Nonparaeil, Mamaie, Shokoufeh, Sahand, ‘Ferragnès,’ 1–16, 1–25, A200, 13–40 budded on GF677 rootstock, and GF677 (without budding)) and irrigation water salinity in five levels (0, 1.2, 2.4, 3.6, and 4.8 g/l of natural salt (equal electrical conductivity 0.5, 2.5, 4.9, 7.3, and 9.8 dS/m, respectively) and with 4 replication for each treatment in research greenhouse of Seed and Plant Institute in years 2013 and 2014. The results showed that with increasing salinity concentration, growth indicators include the branch height, branch diameter, number of total leaves, percentage of green leaves, leaf density on the main branch, leaf area and leaf area ratio, relative humidity content, chlorophyll index, chlorophylls a, b, total, scion fresh and dry weight, root fresh and dry weight have been reduced in the all genotypes studied, but percentage of necrotic leaves, percentage of downfall leaves, root fresh and dry weight ratio to scion fresh and dry weight, relative ionic percentage, and cell membrane injury percentage of leaves were increased. The results of chlorophyll fluorescence showed that salinity stress affected on the young trees by increasing the amount of minimum fluorescence (FO) and decreasing the maximum fluorescence (Fm) and reduced variable fluorescence (Fv) in the plants and reduced variable fluorescence ratio to maximum fluorescence of 0.83 in the control plants to 0.72 in Sahand cultivar and GF677 rootstock. The result showed that type of scion was affected in obstruction of Na+ absorption by the roots and their transported to leaves, as well as was affected in increasing uptake of K+ by the roots and their transported to leaves. In this research, GF677 is well tolerated to water salinity to 4.9 dS/m but with higher range of salinity showed stress effects. The result showed that type of genotypes budded on GF677 rootstock was very effective in tolerant to salinity. Overall, ‘Ferragnès’ was recognized as the most tolerant cultivar to salinity stress. This cultivar could tolerate salinity 3.6 g/l (Ec: 7.3 dS/m). Also, Sahand was recognized as the most sensitive cultivar to salinity stress. 相似文献
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Valère Kolawolé Salako Belarmain Fandohan Barthélémy Kassa Achille Ephrem Assogbadjo Alix Franck Rodrigue Idohou Rodrigue Castro Gbedomon Sebastian Chakeredza Mohammad Ehsan Dulloo Romain Glele Kakaï 《Genetic Resources and Crop Evolution》2014,61(2):313-330
Despite growing literature supporting the importance of home gardens (HG) as biodiversity hotspots, knowledge of patterns of their contribution to conservation of threatened species and crop wild relatives (CWR) across climate and culture in Africa is still limited. This investigation was conducted across three climatic zones to assess the floristic diversity of home gardens and the extent to which they contribute to conservation of threatened species and CWR. Overall, 240 home gardens were sampled and their floristic diversity assessed. The ecological importance of recorded species was determined per climatic zone using the importance value index (IVI). A cluster analysis was performed to group the species according to their IVI-values and a principal component analysis helped to identify the most important species. 285 species were inventoried throughout the study area. Home garden species’ diversity globally declined from the drier to the wetter zone but was highest in the transition zone. The average number of species found per HG was 10.1 and varied weakly across zones (9.07, Guineo-Congolean zone; 10.77, Sudano-Guinean zone; and 10.53, Sudanian zone). The most important home gardens species in the Sudanian, the Sudano-Guinean and the Guineo-Congolean zones were respectively: Abelmoschus esculentus (L.) Moench and Hibiscus asper Hook.f.; Solanum lycopersicum L. and Zea mays L.; Ipomoea aquatica Forssk. and Senna occidentalis (L.) Link. They were mainly vegetables and used as food and/or medicinal plant species. Twenty CWR and twelve threatened species were recorded and were also mainly used for food and medicinal purposes. Thorough research on socioeconomic factors supporting possession of HG and choice of managed species as well as indigenous management strategies of HG and dynamic of traditional knowledge related to HG may help to deeply assess home gardens’ effectiveness in biodiversity conservation. 相似文献
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Fatemeh Zandi Fatemeh Goshadrou Anna Meyfour Behrouz Vaziri 《Iranian Biomedical Journal》2021,25(4):226
Viruses are obligatory intracellular parasites that use cell proteins to take the control of the cell functions in order to accomplish their life cycle. Studying the viral-host interactions would increase our knowledge of the viral biology and mechanisms of pathogenesis. Studies on pathogenesis mechanisms of lyssaviruses, which are the causative agents of rabies, have revealed some important host protein partners for viral proteins, especially for most studied species, i.e. RABV. In this review article, the key physical lyssavirus-host protein interactions, their contributions to rabies infection, and their exploitation are discussed to improve the knowledge about rabies pathogenesis. Key Words: Host-Pathogen Interactions, Lyssavirus, Rabies 相似文献
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Gholam Ali Kojouri Camellia Taghadosi Hassan Momtaz Ehsan Taheri 《Journal of Equine Veterinary Science》2009
Leptospirosis is a widespread zoonotic disease that affects humans and many species of animals. Leptospiral organisms have long been presumed to be associated with the presence of equine recurrent uveitis (ERU). The connection between ERU and leptospirosis can be established using various techniques. In the current study, we used a polymerase chain reaction (PCR) assay to help establish a diagnosis of ERU caused by Leptospira infection and compared the results with those of enzyme-linked immune assay (ELISA). A total of 31 and 30 serum samples were taken from horses with ERU (based on clinical diagnosis) and horses that were healthy, respectively, between June 2007 and December 2008. The results showed that from 31 affected horses, a total of seven and five samples were positive for leptospiral infection using PCR and ELISA, respectively, whereas there was no evidence of infection with Leptospira spp. in 30 serum samples of healthy horses. All of the positive samples in ELISA were also positive by PCR, whereas PCR detected two positive cases that were negative by ELISA. Although there was no significant difference between these two methods, it is apparent that PCR may be a more reliable tool for detecting the presence of leptospires in ERU. 相似文献
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Zhou Y Fuentes-Hernandez C Shim J Meyer J Giordano AJ Li H Winget P Papadopoulos T Cheun H Kim J Fenoll M Dindar A Haske W Najafabadi E Khan TM Sojoudi H Barlow S Graham S Brédas JL Marder SR Kahn A Kippelen B 《Science (New York, N.Y.)》2012,336(6079):327-332
Organic and printed electronics technologies require conductors with a work function that is sufficiently low to facilitate the transport of electrons in and out of various optoelectronic devices. We show that surface modifiers based on polymers containing simple aliphatic amine groups substantially reduce the work function of conductors including metals, transparent conductive metal oxides, conducting polymers, and graphene. The reduction arises from physisorption of the neutral polymer, which turns the modified conductors into efficient electron-selective electrodes in organic optoelectronic devices. These polymer surface modifiers are processed in air from solution, providing an appealing alternative to chemically reactive low-work function metals. Their use can pave the way to simplified manufacturing of low-cost and large-area organic electronic technologies. 相似文献
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