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A survey was conducted to define the fungi population contaminating onion bulbs in Israel during three growing seasons. Significant rots were found to be caused byBotrytis allii, B. cinerea andAspergillus niger. All the onion stocks tested showed infections, but the severity and identity of the pathogens varied between seasons.B. cinerea andB. allii were the most prevalent fungi in winter-harvested onions. Species ofAspergillus, Penicillium, Fusarium, Rhizopus andTrichoderma were also isolated. The first two were the only species found on summer onions. High fungal contamination had been the main factor affecting an attempt to improve the storage quality and shelf life of the harvested bulbs. Chemical disinfection using a reduced-volume application (RVA) technique was efficient in controlling the major storage rots (caused byA. niger andB. cinerea) of the bulbs, without the major disadvantages of the dipping method. The rate of control was directly correlated with the cover density of the deposited fungicide, but not with the amount deposited. The RVA technique should enable prolongation of postharvest shelf life and storability of onion bulbs.  相似文献   
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Magnetotactic bacteria are present in fresh water and marine sediments of Fortaleza, Brazil, situated close to the geomagnetic equator. Both South-seeking and North-seeking bacteria are present in roughly equal numbers in the same samples. This observation is consistent with the hypothesis that the vertical component of the geomagnetic field selects the predominant polarity type among magnetotactic bacteria in natural environments.  相似文献   
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Honey bees are sensitive to earth strength magnetic fields and are reported to contain magnetite (Fe3O4) in their abdomens. We report bands of cells around each abdominal segment that contain numerous electron-opaque, iron-containing granules. The iron is principally in the form of hydrous iron oxides.  相似文献   
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The purpose of this study was to evaluate the cardiopulmonary effects of anesthetic induction with diazepam/ketamine or xylazine/ketamine with subsequent maintenance of anesthesia using isoflurane in foals undergoing abdominal surgery. Seventeen foals underwent laparotomy at 7–10 days of age and a laparoscopy 7–10 days later. Foals were randomly assigned to receive xylazine (0.8 mg kg?1)/ketamine (2 mg kg?1) (X/K)(n = 9) or diazepam (0.2 mg kg?1)/ketamine (2 mg kg?1) (D/K)(n = 8) for induction of anesthesia for both procedures. In all foals, anesthesia was maintained with isoflurane in oxygen with the inspired concentration adjusted to achieve adequate depth of anesthesia as assessed by an individual blinded to the treatments. IPPV was employed throughout using a tidal volume of 10 mL kg?1 adjusting the frequency to maintain eucapnia (PaCO2 35–45 mm Hg, 4.7–6.0 kPa). Cardiopulmonary variables were measured after induction of anesthesia prior to, during, and following surgery. To compare the measured cardiopulmonary variables between the two anesthetic regimes for both surgical procedures, results were analyzed using a three‐way factorial anova for repeated measures (p < 0.05). During anesthesia for laparotomy, mean CI and MAP ranged from 110 to 180 mL kg?1 minute?1 and 57–81 mm Hg, respectively, in the D/K foals and 98–171 mL kg?1 minute?1 and 50–66 mm Hg in the X/K foals. Overall, CI, HR, SAP, DAP, and MAP were significantly higher in foals in the D/K group versus the X/K group during this anesthetic period. During anesthesia for laparoscopy, mean CI and MBP ranged from 85 to 165 mL kg?1 minute?1 and 67–83 mm Hg, respectively, in the D/K group, and 98–171 mL kg?1 minute?1 and 48–67 mm Hg in the X/K group. Only HR, SAP, DAP, and MAP were significantly higher in the D/K group versus X/K group during this latter anesthetic period. There were no significant differences between groups during either surgical procedure for end‐tidal isoflurane, PaO2, PaCO2, or pH. In conclusion, anesthesia of foals for laparotomy and laparoscopy with diazepam/ketamine/isoflurane is associated with less hemodynamic depression than with xylazine/ketamine/isoflurane.  相似文献   
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The nutritional benefits generally recognized for the consumption of extra virgin olive oil (EVOO) are based on a large number of dietary trials of several international populations and intervention studies. Unfortunately, many authors in this field used questionable analytical methods and commercial kits that were not validated scientifically to evaluate the complex bioactive constituents of EVOO and lipid oxidation and decomposition products. Many questionable antiradical methods were commonly used to evaluate natural polyphenolic antioxidants, including an indirect method to determine low-density lipoprotein (LDL) cholesterol. Extensive differences were observed in experimental design, diet control, populations of different ages and problems of compliance intervention, and questionable biomarkers of oxidative stress. Analyses in many nutritional studies were limited by the use of one-dimensional methods to evaluate multifunctional complex bioactive compounds and plasma lipid profiles by the common applications of commercial kits. Although EVOO contains polyphenolic compounds that exhibit significant in vitro antioxidant activity, much more research is needed to understand the absorption and in vivo activity. Many claims of in vivo human beneficial effects by the consumption of EVOO may be overstated. No distinctions were apparently made between in vivo studies based on general health effects in large populations of human subjects and smaller scale well-controlled feeding trials using either pure or mixtures of known phenolic constituents of EVOO. More reliable protocols and testing methods are needed to better validate the complex nutritional properties of EVOO.  相似文献   
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Hybrid seed production steps are evaluated and the pertinent literature reviewed. Experimental data are presented of environmental effects on pollination efficiency, pollen germination, and speed of pollen tube growth. A comparison between the use of male sterile and male fertile ovule parents bears out the superior efficiency of the former in hybrid seed production.This work was aided in 1963 by a grant from the National Council for Research and Development (Israel). Contribution from the National and University Institute of Agriculture, Rehovot. Israel 1966 Series; No. 1077-E.  相似文献   
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