Bar-Ilan University

About: Bar-Ilan University is a education organization based out in Ramat Gan, Israel. It is known for research contribution in the topics: Population & Poison control. The organization has 12835 authors who have published 34964 publications receiving 995648 citations. The organization is also known as: Bar Ilan University & BIU.

Destruction of erythroleukaemic cells by photoactivation of endogenous porphyrins

Abstract: Selective destruction of Friend erythroleukaemic cells (FELC) was potentiated by stimulation of endogenous porphyrin synthesis followed by light sensitization. Endogenous porphyrin biosynthesis in FELC was induced by supplementation of 5-amino levulinic acid (5-ALA) at a concentration of 5 X 10(-4) M. The main accumulated product, after 4 days culture, was uroporphyrin, while after 8 days culture the cells were loaded with protoporphyrin, up to 1.5 micrograms 10(-7) cells. Photoirradiation of the cells for 2 min, accumulating endogenous porphyrins, induced cardinal deformations and cell disintegration in greater than 95% of the cells, as examined by scanning electron microscopy (SEM). The photodynamic destruction effects were dependent on cultivation time with 5-ALA. Flow cytometry analysis showed an immediate expansion of cell volume subsequent to irradiation, presumably a consequence of water influx. Transmission electron microscopy (TEM) of photosensitized cells after different time intervals of culture in 5-ALA medium, revealed initial damage to mitochondria and water influx into the nuclear envelope, after 2 days. After 3-4 days in culture the water influx phenomenon was pronounced, chromatin condensation took place and slight rupture of the outer membrane was detected. Cells photosensitized after 5-6 days of culture were completely disintegrated leaving a nuclear remnant and an enormously swollen nuclear envelope. The culture time dependence of the process, showed an interrelationship between the photodynamic effect and porphyrin accumulation sites in cellular compartments. The study presents a specific method for erythroleukaemic cell inactivation.

Is there intergenerational transmission of trauma? The case of combat veterans' children.

Abstract: This article is a review of the literature on intergenerational transmission of posttraumatic stress disorder (PTSD) from fathers to sons in families of war veterans. The review addresses several questions: (1) Which fathers have a greater tendency to transmit their distress to their offspring? (2) What is transmitted from father to child? (3) How is the distress transmitted and through which mechanisms? And finally, (4) Which children are more vulnerable to the transmission of PTSD distress in the family? Whereas the existing literature deals mainly with fathers' PTSD as a risk for increased emotional and behavior problems among the children, this review also highlights the current paucity of knowledge regarding family members and extrafamilial systems that may contribute to intergenerational transmission of PTSD or to its moderation. Little is also known about resilience and strengths that may mitigate or prevent the risk of intergenerational transmission of trauma.

Database of diazotrophs in global ocean: abundance, biomass and nitrogen fixation rates

Abstract: . Marine N2 fixing microorganisms, termed diazotrophs, are a key functional group in marine pelagic ecosystems. The biological fixation of dinitrogen (N2) to bioavailable nitrogen provides an important new source of nitrogen for pelagic marine ecosystems and influences primary productivity and organic matter export to the deep ocean. As one of a series of efforts to collect biomass and rates specific to different phytoplankton functional groups, we have constructed a database on diazotrophic organisms in the global pelagic upper ocean by compiling about 12 000 direct field measurements of cyanobacterial diazotroph abundances (based on microscopic cell counts or qPCR assays targeting the nifH genes) and N2 fixation rates. Biomass conversion factors are estimated based on cell sizes to convert abundance data to diazotrophic biomass. The database is limited spatially, lacking large regions of the ocean especially in the Indian Ocean. The data are approximately log-normal distributed, and large variances exist in most sub-databases with non-zero values differing 5 to 8 orders of magnitude. Reporting the geometric mean and the range of one geometric standard error below and above the geometric mean, the pelagic N2 fixation rate in the global ocean is estimated to be 62 (52–73) Tg N yr−1 and the pelagic diazotrophic biomass in the global ocean is estimated to be 2.1 (1.4–3.1) Tg C from cell counts and to 89 (43–150) Tg C from nifH-based abundances. Reporting the arithmetic mean and one standard error instead, these three global estimates are 140 p 9.2 Tg N yr−1, 18 p 1.8 Tg C and 590 p 70 Tg C, respectively. Uncertainties related to biomass conversion factors can change the estimate of geometric mean pelagic diazotrophic biomass in the global ocean by about p70%. It was recently established that the most commonly applied method used to measure N2 fixation has underestimated the true rates. As a result, one can expect that future rate measurements will shift the mean N2 fixation rate upward and may result in significantly higher estimates for the global N2 fixation. The evolving database can nevertheless be used to study spatial and temporal distributions and variations of marine N2 fixation, to validate geochemical estimates and to parameterize and validate biogeochemical models, keeping in mind that future rate measurements may rise in the future. The database is stored in PANGAEA ( doi:10.1594/PANGAEA.774851 ).

Sonochemical Synthesis of SnO2 Nanoparticles and Their Preliminary Study as Li Insertion Electrodes

Abstract: SnO2 semiconductor nanoparticles were synthesized by an ultrasonic irradiation of an aqueous solution of SnCl4 and azodicarbonamide under ambient air. These nanoparticles are ∼3−5 nm in size, as calculated using the Debye−Scherrer formula, and as observed by TEM. The SnO2 nanoparticles were also characterized by powder X-ray diffraction (XRD), reflection spectroscopy and FT-IR spectroscopy, transmission electron microscopy (TEM), DSC, and TGA. The band gap was calculated from reflection spectroscopy. Electrochemical tests were performed using the SnO2 nanoparticles as the electrode's materials in nonaqueous Li salt solutions. The results showed promising reversibility, cycle life and high capacity for lithium insertion into the SnO2 nanoparticles.

Impartiality, Justice and Fairness: The Ethics of Concurrent Termination

Abstract: The method of well founded structures for proving termination of programs is extended to concurrent programs. The more complicated case is when a program terminates only for fair executions. Different versions of fairness are introduced: Impartiality, Fairness and Justice, and Methods for proving their termination are presented.