49 research outputs found

    The New Economy of Corporate Citizenship

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    This short publication defines and describes the notions of corporate citizenship and of the New Economy. It explores the social and environmental challenges and opportunities posed by the New Economy, and the approaches to corporate citizenship that are enabled or disabled by its emergence, particularly regarding social partnerships

    NGTS clusters survey -- II. White-light flares from the youngest stars in Orion

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    We present the detection of high energy white-light flares from pre-main sequence stars associated with the Orion complex, observed as part of the Next Generation Transit Survey (NGTS). With energies up to 5.2×10355.2\times10^{35} erg these flares are some of the most energetic white-light flare events seen to date. We have used the NGTS observations of flaring and non-flaring stars to measure the average flare occurrence rate for 4 Myr M0-M3 stars. We have also combined our results with those from previous studies to predict average rates for flares above 1×10351\times10^{35} ergs for early M stars in nearby young associations.STFC ST/M001962/1; ST/P000495/

    Partial reconstitution of DNA large loop repair with purified proteins from Saccharomyces cerevisiae

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    Small looped mispairs are corrected by DNA mismatch repair. In addition, a distinct process called large loop repair (LLR) corrects heteroduplexes up to several hundred nucleotides in bacteria, yeast and human cells, and in cell-free extracts. Only some LLR protein components are known, however. Previous studies with neutralizing antibodies suggested a role for yeast DNA polymerase δ (Pol δ), RFC and PCNA in LLR repair synthesis. In the current study, biochemical fractionation studies identified FEN1 (Rad27) as another required LLR component. In the presence of purified FEN1, Pol δ, RFC and PCNA, repair occurred on heteroduplexes with loops ranging from 8 to 216 nt. Repair utilized a 5′ nick, with correction directed to the nicked strand, irrespective of which strand contained the loop. In contrast, repair of a G/T mismatch occurred at low levels, suggesting specificity of the reconstituted system for looped mispairs. The presence of RPA enhanced reactivity on some looped substrates, but RPA was not required for activity. Although additional LLR factors remain to be identified, the excision and resynthesis steps of LLR from a 5′ nick can be reconstituted in a purified system with FEN1 and Pol δ, together with PCNA and its loader RFC

    Automatic vetting of planet candidates from ground based surveys : machine learning with NGTS

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    State of the art exoplanet transit surveys are producing ever increasing quantities of data. To make the best use of this resource, in detecting interesting planetary systems or in determining accurate planetary population statistics, requires new automated methods. Here we describe a machine learning algorithm that forms an integral part of the pipeline for the NGTS transit survey, demonstrating the efficacy of machine learning in selecting planetary candidates from multi-night ground based survey data. Our method uses a combination of random forests and self-organising-maps to rank planetary candidates, achieving an AUC score of 97.6% in ranking 12368 injected planets against 27496 false positives in the NGTS data. We build on past examples by using injected transit signals to form a training set, a necessary development for applying similar methods to upcoming surveys. We also make the autovet code used to implement the algorithm publicly accessible. autovet is designed to perform machine learned vetting of planetary candidates, and can utilise a variety of methods. The apparent robustness of machine learning techniques, whether on space-based or the qualitatively different ground-based data, highlights their importance to future surveys such as TESS and PLATO and the need to better understand their advantages and pitfalls in an exoplanetary context

    RADNE VRIJEDNOSTI I SOCIJALNO-KOMUNIKATIVNE VJEŠTINE STUDENATA TURIZMA

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    When it comes to work, tourism is very difficult and complex activity. In comparison to other sectors, tourism work is characterized by relatively low wages, the unfavourable working time that impoverishes family and social lives of employees, distinct subordination in labour relations, limited opportunities for advancement and due to all that high rates of turnover. Education of employees in tourism certainly mitigates these harsh conditions, and what is very important, education means a change in the values associated with the work. Transferring work values occurs intergenerational; it is the result of intergenerational communication. This research has thus focused on the extent to which the work values of the students studying in the field of tourism are similar to, or different from the values of the students from other academic areas. The results have shown that the current generations of students who are studying to work in the field of tourism activities are not any different from previous generations concerning those values that allow personal growth and development. However, a major difference has occurred in the area of utilitarian values. Modern generations have valued utilitarian values much higher than those generations 30 years ago, when the research which served as the basis for the study presented here was carried out.Turizam je, kada se govori o radu, vrlo teška i kompleksna djelatnost. Rad u turizmu karakteriziran je relativno niskim plaćama u usporedbi s drugim sektorima, nepovoljnim radnim vremenom koje osiromašuje obiteljski i društveni život zaposlenih, izrazitom podređenošću u radnim odnosima, malim mogućnostima napredovanja i zbog svega toga visokim stopama turnover. Obrazovanje radne snage svakako ublažava ove teške uvjete rada. Obrazovanje znači i promjenu u vrijednostima povezanim s radom. Prijenos radnih vrijednosti događa se međugeneracijski; on je rezultat međugeneracijske komunikacije. Inters ovog istraživanja bio je usmjeren prema tome u kojoj su mjeri radne vrijednosti studenata koji studiraju na području turizma slične ili različite studentima drugih akademskih područja. Rezultati su pokazali da se sadašnja generacija studenata koji se obrazuju za rad u području turističke djelatnosti ne razlikuje od ranijih generacija u području onih vrijednosti koje omogućuju osobni rast i razvoj. Bitna je razlika u području utalitarnih vrijednosti. Suvremene generacije vrednuju te vrijednosti znatno više nego one prije 30 godina, kada je izvedeno istraživanje koje je poslužilo kao osnova za istraživanje koje se ovdje prikazuje

    NGTS and HST insights into the long-period modulation in GW Librae

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    Light curves of the accreting white dwarf pulsator GW Librae spanning a 7.5-month period in 2017 were obtained as part of the Next-Generation Transit Survey. This data set comprises 787 h of photometry from 148 clear nights, allowing the behaviour of the long (hours) and short-period (20 min) modulation signals to be tracked from night to night over a much longer observing baseline than has been previously achieved. The long-period modulations intermittently detected in previous observations of GW Lib are found to be a persistent feature, evolving between states with periods ≃ 83 min and 2–4 h on time-scales of several days. The 20 min signal is found to have a broadly stable amplitude and frequency for the duration of the campaign, but the previously noted phase instability is confirmed. Ultraviolet observations obtained with the Cosmic Origin Spectrograph on-board the Hubble Space Telescope constrain the ultraviolet-to-optical flux ratio to ≃5 for the 4 h modulation, and ≲1 for the 20 min period, with caveats introduced by non-simultaneous observations. These results add further observational evidence that these enigmatic signals must originate from the white dwarf, highlighting our continued gap in theoretical understanding of the mechanisms that drive them

    An ultrahot Neptune in the Neptune desert

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    About 1 out of 200 Sun-like stars has a planet with an orbital period shorter than one day: an ultrashort-period planet. All of the previously known ultrashort-period planets are either hot Jupiters, with sizes above 10 Earth radii (R⊕), or apparently rocky planets smaller than 2 R⊕. Such lack of planets of intermediate size (the ‘hot Neptune desert’) has been interpreted as the inability of low-mass planets to retain any hydrogen/helium (H/He) envelope in the face of strong stellar irradiation. Here we report the discovery of an ultrashort-period planet with a radius of 4.6 R⊕ and a mass of 29 M⊕, firmly in the hot Neptune desert. Data from the Transiting Exoplanet Survey Satellite revealed transits of the bright Sun-like star LTT 9779 every 0.79 days. The planet’s mean density is similar to that of Neptune, and according to thermal evolution models, it has a H/He-rich envelope constituting 9.0^(+2.7)_(−2.9)% of the total mass. With an equilibrium temperature around 2,000 K, it is unclear how this ‘ultrahot Neptune’ managed to retain such an envelope. Follow-up observations of the planet’s atmosphere to better understand its origin and physical nature will be facilitated by the star’s brightness (V_(mag) = 9.8)

    Finishing the euchromatic sequence of the human genome

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    The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead
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