On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ∼ 1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40 − 8 + 8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 M ⊙ . An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ∼ 40 Mpc ) less than 11 hours after the merger by the One-Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ∼10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ∼ 9 and ∼ 16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC 4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta.

Merging neutron stars offer an excellent laboratory for simultaneously studying strong-field gravity and matter in extreme environments. We establish the physical association of an electromagnetic counterpart (EM170817) with gravitational waves (GW170817) detected from merging neutron stars. By synthesizing a panchromatic data set, we demonstrate that merging neutron stars are a long-sought production site forging heavy elements by r-process nucleosynthesis. The weak gamma rays seen in EM170817 are dissimilar to classical short gamma-ray bursts with ultrarelativistic jets. Instead, we suggest that breakout of a wide-angle, mildly relativistic cocoon engulfing the jet explains the low-luminosity gamma rays, the high-luminosity ultraviolet-optical-infrared, and the delayed radio and x-ray emission. We posit that all neutron star mergers may lead to a wide-angle cocoon breakout, sometimes accompanied by a successful jet and sometimes by a choked jet.

Recent years have brought additional data on the benefits of prebiotics and probiotics treatment in patients with atopic dermatitis. This review includes all the articles published in PubMed, Scopus, Embase and Cochrane databases until 05.06.2018. The terms used for the search were 'prebiotic', 'probiotic', 'atopic dermatitis', 'Severity Scoring of Atopic Dermatitis', and 'SCORAD'. There was an increase of the intestinal permeability reported in patients with atopic dermatitis and a reduction of the cutaneous microbiome diversity. Probiotics modulate the general microbiome and immune status by improving the intestinal barrier; these effects can be responsible for reducing allergic phenomenon and atopic dermatitis severity. We have structured the results by age groups as infants, 1-18 years, adults, and also pregnancy and lactation. Literature does not offer yet answers on the issues such as the optimal dosing, duration needed to see beneficial effects, the optimal time to start the treatment; the personalized use of probiotics according to colonic dysbiosis may be associated with better results. However, most randomized controlled trials and meta-analyzes support the administration of probiotics for at least 8 weeks in order to obtain beneficial effects in improving severity scoring of atopic dermatitis. Contents 1. Introduction 2. Definition of terms 3. Modulating the human microbiome by pre-and probiotics 4. Prebiotic and probiotic in atopic dermatitis 5. The type of probiotics used in clinical trials 6. Prebiotics-mechanism of action 7. Probiotics-mechanism of action 8. Conclusion

There has been speculation about a class of relativistic explosions with an initial Lorentz factor Γ init smaller than that of classical gamma-ray bursts (GRBs). These "dirty fireballs" would lack prompt GRB emission but could be pursued via their optical afterglow, appearing as transients that fade overnight. Here we report a search for such transients (that fade by 5-σ in magnitude overnight) in four years of archival photometric data from the intermediate Palomar Transient Factory (iPTF). Our search criteria yielded 50 candidates. Of these, two were afterglows to GRBs that had been found in dedicated follow-up observations to triggers from the Fermi GRB Monitor. Another (iPTF14yb) was a GRB afterglow discovered serendipitously. Eight were spurious artifacts of reference image subtraction, and one was an asteroid. The remaining 38 candidates have red stellar counterparts in external catalogs. The photometric and spectroscopic properties of the counterparts identify these transients as strong flares from M dwarfs of spectral type M3-M7 at distances of d≈0.15-2.1 kpc; three counterparts were already spectroscopically classified as late-type M stars. With iPTF14yb as the only confirmed relativistic outflow discovered independently of a high-energy trigger, we constrain the all-sky rate of transients that peak at m=18 and fade by Δm=2 mag in Δt=3 hr to be 680 yr 1 -, with a 68% confidence interval of 119 2236 yr 1 --. This implies that the rate of visible dirty fireballs is at most comparable to that of the known population of long-duration GRBs.

Sketching techniques can provide approximate answers to aggregate queries either for data-streaming or distributed computation. Small space summaries that have linearity properties are required for both types of applications. The prevalent method for analyzing sketches uses moment analysis and distribution independent bounds based on moments. This method produces clean, easy to interpret, theoretical bounds that are especially useful for deriving asymptotic results. However, the theoretical bounds obscure fine details of the behavior of various sketches and they are mostly not indicative of which type of sketches should be used in practice. Moreover, no significant empirical comparison between various sketching techniques has been published, which makes the choice even harder. In this paper, we take a close look at the sketching techniques proposed in the literature from a statistical point of view with the goal of determining properties that indicate the actual behavior and producing tighter confidence bounds. Interestingly, the statistical analysis reveals that two of the techniques, Fast-AGMS and CountMin, provide results that are in some cases orders of magnitude better than the corresponding theoretical predictions. We conduct an extensive empirical study that compares the different sketching techniques in order to corroborate the statistical analysis with the conclusions we draw from it. The study indicates the expected performance of various sketches, which is crucial if the techniques are to be used by practitioners. The overall conclusion of the study is that Fast-AGMS sketches are, for the full spectrum of problems, either the best, or close to the best, sketching technique. This makes Fast-AGMS sketches the preferred choice irrespective of the situation.

DBO is a database system that utilizes randomized algorithms to give statistically meaningful estimates for the final answer to a multi-table, disk-based query from start to finish during query execution. However, DBO's "time 'til utility" (or "TTU"; that is, the time until DBO can give a useful estimate) can be overly large, particularly in the case that many database tables are joined in a query, or in the case that a join query includes a very selective predicate on one or more of the tables, or when the data are skewed. In this paper, we describe Turbo DBO, which is a prototype database system that can answer multi-table join queries in a scalable fashion, just like DBO. However, Turbo DBO often has a much lower TTU than DBO. The key innovation of Turbo DBO is that it makes use of novel algorithms that look for and remember "partial match" tuples in a randomized fashion. These are tuples that satisfy some of the boolean predicates associated with the query, and can possibly be grown into tuples that actually contribute to the final query result at a later time.

Sketching techniques provide approximate answers to aggregate queries both for data-streaming and distributed computation. Small space summaries that have linearity properties are required for both types of applications. The prevalent method for analyzing sketches uses moment analysis and distribution-independent bounds based on moments. This method produces clean, easy to interpret, theoretical bounds that are especially useful for deriving asymptotic results. However, the theoretical bounds obscure fine details of the behavior of various sketches and they are mostly not indicative of which type of sketches should be used in practice. Moreover, no significant empirical comparison between various sketching techniques has been published, which makes the choice even harder. In this article we take a close look at the sketching techniques proposed in the literature from a statistical point of view with the goal of determining properties that indicate the actual behavior and producing tighter confidence bounds. Interestingly, the statistical analysis reveals that two of the techniques, Fast-AGMS and Count-Min, provide results that are in some cases orders of magnitude better than the corresponding theoretical predictions. We conduct an extensive empirical study that compares the different sketching techniques in order to corroborate the statistical analysis with the conclusions we draw from it. The study indicates the expected performance of various sketches, which is crucial if the techniques are to be used by practitioners. The overall conclusion of the study is that Fast-AGMS sketches are, for the full spectrum of problems, either the best, or close to the best, sketching technique. We apply the insights obtained from the statistical study and the experimental results to design effective algorithms for sketching interval data. We show how the two basic methods for sketching interval data, DMAP and fast range-summation, can be improved significantly with respect to the update time without a significant loss in accuracy. The gain in update time can be as large as two orders of magnitude, thus making the improved methods practical. The empirical study suggests that DMAP is preferable when update time is the critical requirement and fast range-summation is desirable for better accuracy.

The exact computation of aggregate queries, like the size of join of two relations, usually requires large amounts of memory-constrained in data-streaming-or communication-constrained in distributed computation-and large processing times. In this situation, approximation techniques with provable guarantees, like sketches, are one possible solution. The performance of sketches depends crucially on the ability to generate particular pseudo-random numbers. In this paper we investigate both theoretically and empirically the problem of generating k-wise independent pseudo-random numbers and, in particular, that of generating 3 and 4-wise independent pseudorandom numbers that are fast range-summable (i.e., they can be summed-up in sub-linear time). Our specific contributions are: (a) we provide a thorough comparison of the various pseudorandom number generating schemes, (b) we study both theoretically and empirically the fast range-summation property of the 3 and 4-wise independent generating schemes, (c) we provide algorithms for the fast range-summation of two 3-wise independent schemes, BCH and Extended Hamming, (d) we show convincing theoretical and empirical evidence that the Extended Hamming scheme performs as well as any 4-wise independent scheme for estimating the size of join of two relations using AMS-sketches, even though it is only 3-wise independent. We use this scheme to generate estimators that significantly outperform the state-of-the-art solutions for two problems-size of spatial joins and selectivity estimation.