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1.
A technique for rearing the progeny of wildCeratitis capitata flies was developed. The method is based on wild captured flies which are allowed to oviposit in artificial fruit containing
larval rearing medium. Flies develop in the fruit from eggs to last larval instar, then exit the fruit and pupate within vermiculite.
This method was shown to be feasible and efficient, and to increase considerably the number of wild flies for testing purposes.
Possible contribution to the Sterile Insect Technique (SIT) and potential applications of the method are discussed. 相似文献
2.
Tamar Kaffe-Abramovich 《Soil biology & biochemistry》2006,38(7):1966-1976
The aim of the current study was to gain a better understanding of the changes that occur in soil microbial community and in its functional diversity as a result of the use of nematocide and biocide inhibitors in natural ecosystems. Both inhibitors are known to have a great effect on the nematode community and total biota, playing an important role in soil food web and biota interactions. The experiment was set up in the Negev Desert using sixteen 1×1 m soil plots, to which two chemical inhibitors were applied: (a) a biocide, to eliminate the whole biotic community; and (b) a nematocide, to eliminate the nematode community in soil. In addition, water treatment was applied to the same soil plots, while untreated soil plots were used as control. Microbial functional diversity, together with abiotic parameters such as soil moisture and total organic carbon, was tested monthly in soil samples collected from the 0-10 and 10-20 cm soil layers. The results of the abiotic parameters showed similar patterns in the two soil layers regardless of the inhibitor treatments. An increase in soil water content followed rainfall patterns. Total organic carbon was low during the wet season and increased during the dry seasons. The Shannon-Weaver index value for microbial functional diversity was found to increase in spring after the wet season in both soil layers. In the upper soil layer, an increase was observed both in the inhibitor and water treatments. However, the increase in the water treatment lasted longer compared to the increase observed in the inhibitor-treated soil plots. In the 10-20 cm soil layer, a different pattern was observed: an increase in microbial functional diversity was observed in the inhibitor-treated soil plots, while an increase in the water-treated soil plots was seen at a later stage. Principal Component Analysis was also conducted, revealing different patterns between inhibitors and water treatments on both a temporal scale, when changes from a homogeneous to heterogeneous consumption pattern were observed, and in the nature of communities that proliferate in the soil. Differences were also observed in the microbial community between the upper 0-10 and the lower 10-20 cm soil layers, where an opposite pattern of substrate consumption was observed. This study emphasizes the important role the biotic component plays in the soil of an arid climate, studying the long-term effects of key species elimination on the microbial community in desert soil. 相似文献
3.
Tamar Akhvlediani Nazibrola Chitadze Rusudan Chlikadze Nino Rostiashvili Medea Betashvili Paata Imnadze Robert G. Rivard Mikeljon P. Nikolich Michael A. Washington Christian T. Bautista 《Zoonoses and public health》2019,66(7):835-841
Zoonotic diseases are endemic in the country of Georgia. Using the non‐linear canonical correlation (NCC) method, the aim of this study was to examine the relationship between thirteen epidemiological risk factors and seropositivity to five zoonotic infections (anthrax, Q fever, tularemia, leptospirosis, and Crimean‐Congo hemorrhagic fever [CCHF]) among Georgian military recruits during 2014–2016. According to this multivariate statistical technique, which is suitable for the analysis of two or more sets of qualitative variables simultaneously, two canonical variables were identified. These variables accounted for 68% of the variation between the two sets of categorical variables (“risk factors” and “zoonotic infections”). For the first canonical variable, there was a relationship among CCHF (canonical loading, which is interpreted in the same way as the Pearson's correlation coefficient, [cl] = 0.715), tick bites (cl = 0.418) and slaughter of animals (cl = 0.351). As for the second canonical variable, Q fever (cl = ?0.604) and leptospirosis (cl = ?0.486) were related to rodents inside and outside home (cl = ?0.346) and sweeping in or around home (cl = ?0.317). The NCC method allows researchers to obtain additional insights into the complex relationship between epidemiological risk factors and multiple zoonotic infections. 相似文献
4.
Substrates coated with specific bioactive ligands are important for tissue engineering, enabling the local presentation of extracellular stimulants at controlled positions and densities. In this study, we examined the cross-talk between integrin and epidermal growth factor (EGF) receptors following their interaction with surface-immobilized Arg-Gly-Asp (RGD) and EGF ligands, respectively. Surfaces of glass coverslips, modified with biotinylated silane-polyethylene glycol, were functionalized by either biotinylated RGD or EGF (or both) via the biotin-NeutrAvidin interaction. Fluorescent labeling of the adhering A431 epidermoid carcinoma cells for zyxin or actin indicated that EGF had a dual effect on focal adhesions (FA) and stress fibers: at low concentrations (0.1; 1 ng/ml), it stimulated their growth; whereas at higher concentrations, on surfaces with low to intermediate RGD densities, it induced their disassembly, leading to cell detachment. The EGF-dependent dissociation of FAs was, however, attenuated on higher RGD density surfaces. Simultaneous stimulation by both immobilized RGD and EGF suggest a strong synergy between integrin and EGFR signaling, in FA induction and cell spreading. A critical threshold level of EGF was required to induce significant variation in cell adhesion; beyond this critical density, the immobilized molecule had a considerably stronger effect on cell adhesion than did soluble EGF. The mechanisms underlying this synergy between the adhesion ligand and EGF are discussed. 相似文献
5.
Ji Hyun Kim Sophie Fridman Hamutal Borochov‐Neori Tamar Sinai Dina Zilberg 《Aquaculture Research》2019,50(2):431-438
Garlic (Allium sativum) has been shown to possess antimicrobial properties against a range of disease‐causing agents, including fish parasites. Our study aimed to investigate the potential use of garlic as a treatment against Cryptocaryon irritans infection, using guppies (Poecilia reticulata) as the fish model. Garlic was freeze‐dried, powdered, and used as it is or as an aqueous extract. The content of allicin, its main active ingredient, was 1.25 mg/g in garlic powder and 0.82 mg/ml in the aqueous extract, as determined by HPLC analysis. Aqueous garlic extract fully immobilized C. irritans theronts and protomonts within 20 and 40 min, respectively, following exposure to 5 µl/ml. Treatment trials were performed, in which infected fish were fed with garlic powder‐supplemented feeds (5%, 10%, or 20% supplementation), bathed in garlic aqueous extract (250 or 500 µl/L) and subjected to a combined treatment which included both feeding and bathing. Results revealed that the tested treatments failed to cure the infection, though reduction in infection intensity on the caudal fin, but not on the gills, was evident following dietary supplementation with 20% of powdered garlic in one of the trials. 相似文献
6.
Context
Artificial light at night (ALAN) provides an array of important benefits but might also adversely affect humans and other living organisms. Yet, the existing reviews of accumulated knowledge about the multifaceted effects associated with exposure to ALAN focus on distinct ecosystem components. As a result, our understanding of potential system-wide impacts of ALAN exposure is insufficient.
ObjectivesThis paper attempts to bridge this knowledge gap by reviewing a wide range of studies, with a particular focus on identifying the impacts of ALAN exposure that are common to different species.
MethodsThe survey is conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and covers peer-reviewed articles published from 2000 to 2019.
ResultsSeventy-four eligible articles, out of 1223 initially identified, were selected and synthesized. 20% of them focus on humans, while the rest explore other living organisms, such as vertebrates, avian species, arthropods, aquatic organisms, and vegetation. The review demonstrates that similar adverse effects of ALAN exposure, ranging from sleep disturbance, depression, weight gain, eating and movement disorders, to elevated risk of cancer, are manifested across different components of the ecosystem, and therefore entail wider and more complex risks to its stability and integrity.
ConclusionTo reduce ecosystem risks, associated with constantly increasing ALAN levels, illumination policies should be based on directional and reduced nighttime lighting, which can help to avoid unnecessary exposures. The study highlights knowledge gaps that warrant further research attention.
相似文献7.
M. Wysoki G. Forer E. Dunkelblum Miriam Harel Polina Fraistat Devora Gordon L. Anshelevich M. Kehat M. Kehat L. Anshelevich Devora Gordon Miriam Harel E. Dunkelblum L. Zilberg A. Rubin A. Shani Ada Rafaeli Miriam Altstein Oma Ben-Aziz Irit Schafler I. Seltzer C. Gilon A. Hefetz Tamar Katzav Victoria Soroker Ali R. Harari 《Phytoparasitica》1998,26(2):175-181
8.
Eden E Geva-Zatorsky N Issaeva I Cohen A Dekel E Danon T Cohen L Mayo A Alon U 《Science (New York, N.Y.)》2011,331(6018):764-768
Cells remove proteins by two processes: degradation and dilution due to cell growth. The balance between these basic processes is poorly understood. We addressed this by developing an accurate and noninvasive method for measuring protein half-lives, called "bleach-chase," that is applicable to fluorescently tagged proteins. Assaying 100 proteins in living human cancer cells showed half-lives that ranged between 45 minutes and 22.5 hours. A variety of stresses that stop cell division showed the same general effect: Long-lived proteins became longer-lived, whereas short-lived proteins remained largely unaffected. This effect is due to the relative strengths of degradation and dilution and suggests a mechanism for differential killing of rapidly growing cells by growth-arresting drugs. This approach opens a way to understand proteome half-life dynamics in living cells. 相似文献
9.
The effect of lead on photosynthetic light storage efficiency was measured by the photoacoustic method. The advantage of this method is in its directness, since the signal obtained by a hydrophone is proportional to that fraction of light energy that is dissipated as heat. This increases as less energy is stored photochemically if the photosynthetic apparatus is damaged. Cells of shape Synechococcus leopoliensis (Cyanobacteria) were grown in medium containing lead in concentrations of 0, 25, 50, 100, and 200 ppm. To avoid the co-precipitation of lead and phosphorus as lead phosphate, phosphorus was omitted from the media used during weeklong exposure to lead. Both chlorophyll concentration and photosynthetic energy storage efficiency decreased with time and with lead concentration. Reduction of photosynthesis progressed with time and increased with lead concentration, reaching up to 80% at the highest lead concentration after seven days. 相似文献
10.
Does mating disruption of Planococcus ficus and Lobesia botrana affect the diversity,abundance and composition of natural enemies in Israeli vineyards? 
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