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.

Dynamics of single mRNP nucleocytoplasmic transport and export through the nuclear pore in living cells

Abstract: The flow of genetic information in eukaryotic cells occurs through the nucleocytoplasmic translocation of mRNAs Knowledge of in vivo messenger RNA export kinetics remains poor in comparison with that of protein transport We have established a mammalian system that allowed the real-time visualization and quantification of large single mRNA-protein complexes (mRNPs) during export The in vivo dynamics of bulk mRNP transport and export, from transcription to the nuclear pore complex (NPC), occurred within a 5-40 minute time frame, with no NPC pile-up mRNP export was rapid (about 05 s) and kinetically faster than nucleoplasmic diffusion Export inhibition demonstrated that mRNA-NPC interactions were independent of ongoing export Nucleoplasmic transport dynamics of intron-containing and intronless mRNAs were similar, yet an intron did increase export efficiency Here we provide visualization and analysis at the single mRNP level of the various steps in nuclear gene expression and the inter-chromatin tracks through which mRNPs diffuse, and demonstrate the kinetics of mRNP-NPC interactions and translocation

Ranking Generated Summaries by Correctness: An Interesting but Challenging Application for Natural Language Inference

Abstract: While recent progress on abstractive summarization has led to remarkably fluent summaries, factual errors in generated summaries still severely limit their use in practice. In this paper, we evaluate summaries produced by state-of-the-art models via crowdsourcing and show that such errors occur frequently, in particular with more abstractive models. We study whether textual entailment predictions can be used to detect such errors and if they can be reduced by reranking alternative predicted summaries. That leads to an interesting downstream application for entailment models. In our experiments, we find that out-of-the-box entailment models trained on NLI datasets do not yet offer the desired performance for the downstream task and we therefore release our annotations as additional test data for future extrinsic evaluations of NLI.

Autonomous Cultivation Before Domestication

Abstract: Early Near Eastern crop cultivation was a trial-and-error process. Some crops continued until full domestication, while others were abandoned and later adopted independently by distant societies.

Primary Production and Photoadaptation in Light- and Shade-Adapted Colonies of the Symbiotic Coral, Stylophora pistillata

Abstract: Photoadaptation by photosynthetic organisms to lowered light intensities occurs in part through changes in pigment concentrations and in characteristics of the photosynthetic response curve. We have characterized photoadaptive responses of light- and shade-adapted colonies of the reef coral Stylophora pistillata , which possesses symbiotic algae (zooxanthellae) and grows naturally under a variety of light intensities in the highly cavernous reefs of the Red Sea. Shade-adapted corals have significantly more chlorophyll per individual zooxanthella cell than light-adapted corals (2.98 compared to 12.97 pg chlorophyll a per cell), but not a significantly different number of cells per unit area (1.00 × 10 6 cells per square centimetre), with the result that the mass of chlorophyll per unit area is greater for shade-adapted corals than for light-adapted corals. Tissue nitrogen content per unit area is significantly lower ( p p > 0.05) in shade forms. These biomass characteristics are concomitant with a variety of func­tional responses to natural light intensities. Rate of photosynthesis at saturating light intensities is the same per unit area in both forms (20.2 µgO 2 cm -2 h -1 for shade specimens; 18.8 for light specimens); but it is significantly different when measured by amount of chlorophyll (1.6 µg O 2 (chl a ) -1 h -1 for shade specimens compared with 5.0 for light specimens). The initial slope of the P: I curve, α , is significantly higher for shade specimens by area (0.21 for shade corals compared with 0.12 for light corals), but significantly lower for shade specimens by amount of chlorophyll a (0.01 for specimens from shade compared to 0.04 for specimens growing in the light). I k (the point at which maximum production begins) is significantly lower for shade specimens (138 µmol m -2 s -1 for shade compared to 273 for light), and likewise I c (the compensation point at which net coral photosynthesis = 0) is also significantly less for shade specimens (30 µmol m -2 s -1 for shade compared to 141 for light). The average nocturnal respiration rate is significantly higher for specimens growing in the light (13.9 µg O 2 cm -2 h -1 for light specimens compared to 7.6 for shade specimens). Corals in intense sunlight respire at almost twice the rate of shade corals, probably in response to their higher total gross production. Owing to higher production rates and lower respiration rates, integrated P c (gross)/ R c (24 h) ratios are greater for shade-adapted specimens either in direct sunlight (1.76 P/R for shade specimens in the light compared to 1.10 for light specimens in the light), or in the shade (0.43 for shade specimens in the cave compared to 0.10 for light specimen in the cave). By using previously defined equations and biomass assumptions, it can be shown that light-adapted Stylophora pistillata can acquire all of their basal metabolic carbon through photosynthesis and translocation, but that shade-adapted Stylophora colonies growing in shade acquire slightly less than half. These results also show that if there were no photoadaptive response, shade-adapted specimens would acquire less than 4 % of their carbon from photosynthesis