1,152 research outputs found
Two Earth-sized planets orbiting Kepler-20
Since the discovery of the first extrasolar giant planets around Sun-like
stars, evolving observational capabilities have brought us closer to the
detection of true Earth analogues. The size of an exoplanet can be determined
when it periodically passes in front of (transits) its parent star, causing a
decrease in starlight proportional to its radius. The smallest exoplanet
hitherto discovered has a radius 1.42 times that of the Earth's radius (R
Earth), and hence has 2.9 times its volume. Here we report the discovery of two
planets, one Earth-sized (1.03R Earth) and the other smaller than the Earth
(0.87R Earth), orbiting the star Kepler-20, which is already known to host
three other, larger, transiting planets. The gravitational pull of the new
planets on the parent star is too small to measure with current
instrumentation. We apply a statistical method to show that the likelihood of
the planetary interpretation of the transit signals is more than three orders
of magnitude larger than that of the alternative hypothesis that the signals
result from an eclipsing binary star. Theoretical considerations imply that
these planets are rocky, with a composition of iron and silicate. The outer
planet could have developed a thick water vapour atmosphere.Comment: Letter to Nature; Received 8 November; accepted 13 December 2011;
Published online 20 December 201
MLPerf Inference Benchmark
Machine-learning (ML) hardware and software system demand is burgeoning.
Driven by ML applications, the number of different ML inference systems has
exploded. Over 100 organizations are building ML inference chips, and the
systems that incorporate existing models span at least three orders of
magnitude in power consumption and five orders of magnitude in performance;
they range from embedded devices to data-center solutions. Fueling the hardware
are a dozen or more software frameworks and libraries. The myriad combinations
of ML hardware and ML software make assessing ML-system performance in an
architecture-neutral, representative, and reproducible manner challenging.
There is a clear need for industry-wide standard ML benchmarking and evaluation
criteria. MLPerf Inference answers that call. In this paper, we present our
benchmarking method for evaluating ML inference systems. Driven by more than 30
organizations as well as more than 200 ML engineers and practitioners, MLPerf
prescribes a set of rules and best practices to ensure comparability across
systems with wildly differing architectures. The first call for submissions
garnered more than 600 reproducible inference-performance measurements from 14
organizations, representing over 30 systems that showcase a wide range of
capabilities. The submissions attest to the benchmark's flexibility and
adaptability.Comment: ISCA 202
Atmospheric Acetaldehyde: Importance of Air-Sea Exchange and a Missing Source in the Remote Troposphere.
We report airborne measurements of acetaldehyde (CH3CHO) during the first and second deployments of the National Aeronautics and Space Administration (NASA) Atmospheric Tomography Mission (ATom). The budget of CH3CHO is examined using the Community Atmospheric Model with chemistry (CAM-chem), with a newly-developed online air-sea exchange module. The upper limit of the global ocean net emission of CH3CHO is estimated to be 34 Tg a-1 (42 Tg a-1 if considering bubble-mediated transfer), and the ocean impacts on tropospheric CH3CHO are mostly confined to the marine boundary layer. Our analysis suggests that there is an unaccounted CH3CHO source in the remote troposphere and that organic aerosols can only provide a fraction of this missing source. We propose that peroxyacetic acid (PAA) is an ideal indicator of the rapid CH3CHO production in the remote troposphere. The higher-than-expected CH3CHO measurements represent a missing sink of hydroxyl radicals (and halogen radical) in current chemistry-climate models
Heritability and genome-wide analyses of problematic peer relationships during childhood and adolescence
Peer behaviour plays an important role in the development of social adjustment, though little is known about its genetic architecture. We conducted a twin study combined with a genome-wide complex trait analysis (GCTA) and a genome-wide screen to characterise genetic influences on problematic peer behaviour during childhood and adolescence. This included a series of longitudinal measures (parent-reported Strengths-and-Difficulties Questionnaire) from a UK population-based birth-cohort (ALSPAC, 4–17 years), and a UK twin sample (TEDS, 4–11 years). Longitudinal twin analysis (TEDS; N ≤ 7,366 twin pairs) showed that peer problems in childhood are heritable (4–11 years, 0.60 < twin-h 2 ≤ 0.71) but genetically heterogeneous from age to age (4–11 years, twin-r g = 0.30). GCTA (ALSPAC: N ≤ 5,608, TEDS: N ≤ 2,691) provided furthermore little support for the contribution of measured common genetic variants during childhood (4–12 years, 0.02<GCTA−h2Meta ≤ 0.11) though these influences become stronger in adolescence (13–17 years, 0.14<GCTA−h2ALSPAC ≤ 0.27). A subsequent cross-sectional genome-wide screen in ALSPAC (N ≤ 6,000) focussed on peer problems with the highest GCTA-heritability (10, 13 and 17 years, 0.0002 < GCTA-P ≤ 0.03). Single variant signals (P ≤ 10−5) were followed up in TEDS (N ≤ 2835, 9 and 11 years) and, in search for autism quantitative trait loci, explored within two autism samples (AGRE: N Pedigrees = 793; ACC: N Cases = 1,453/N Controls = 7,070). There was, however, no evidence for association in TEDS and little evidence for an overlap with the autistic continuum. In summary, our findings suggest that problematic peer relationships are heritable but genetically complex and heterogeneous from age to age, with an increase in common measurable genetic variation during adolescence
Rhetorical Transformations in Multimodal Advertising Texts: From General to Local Degree Zero
The use of rhetoric in advertising research has been steadily gaining momentum since the 1980’s. Coupled with an increased interest in multimodality and the multiple interactions among verbal, pictorial and auditory registers, as structural components of an ad filmic text, the hermeneutic tools furnished by traditional rhetoric have been expanded and elaborated. This paper addresses the fundamental question of how ad filmic texts assume signification from a multimodal rhetorical point of view, by engaging in a fruitful dialogue with various research streams within the wider semiotic discipline and consumer research. By critically addressing the context of analysis of a multimodal ad text in the course of the argumentation deployed by different approaches, such as Social Semiotics (Kress/Leeuwen 2001), Film Semiotics (i.e. Metz 1982, Carroll 1980, Branigan 1982), Visual Semiotics (i.e. Sonesson 2008; 2010, Eco 1972;1976;1986, Groupe " 1992), Consumer Research (i.e. Mick/McQuarrie 1999; 2004, Philips 2003, Scott 1994), the relative merits of a structuralist approach that prioritizes the distinction between local and general degree zero, as put forward by Groupe " (1992), are highlighted. Furthermore, the modes whereby rhetorical transformations are enacted are outlined, with view to deepening the conceptual tackling of degree zero of signification, while addressing its applicability to branding discourse and multimodal ad texts
Portfolio Vol. II N 1
Browne, Phil. The Approach to Fraternity Row . Picture. 2.
Simmons, Fate. The Sand House . Prose. 3.
The College Catbird, Groucho. Ode to my Fellow Students . Poem. 6.
Varney, Chester. The Tramp . Prose. 7.
Browne, Phil. Shell Shock . Prose. 9.
West, Bill C. Mr. Freud... . Poem. 10.
West, Bill C. Bacchanal . Poem. 10.
De Chavannes, Pierre Puvis de. Summer . Poem. 10.
Pierce, Ames. A Student Looks at Europe . Prose. 11.
Timrud, David. Though you Knew it Not . Poem. 13.
Timrud, David. Le Joi De Vivre . Poem. 13.
Timrud, David. The Ghostly Loom . Poem. 13.
Dohanos, Stephen. West Quoddy Light, Maine . Picture. 13.
Millet, Jean Francois. Peasants Going to Work . Picture. 14.
Kent, Rockwell. Maine Coast . Picture. 14.
Beier, Dean. Review of New Recordings . Prose. 15.
Beier, Dean. Advice on Band Booking . Prose. 15.
Millay, Edna St. Vincent. From \u27Conversation at Midnight\u27 . Prose. 16.
Black, James. Playing Around . Prose. 17.
Saunders, Paul. Review of New Books .Prose. 17.
Salietti, Alberto. A country Woman . Picture. 18.
Eschman, Barbara. Color Scheme . Poem. 18.
Whitehead, Richard. A Tribute . Picture. 19.
Beckham, Adela. Gethsemane . Poem. 20.
Beckham, Adela. Blues Singer . Poem. 20.
Flory, Doris. Revelation . Poem. 20.
Flory, Doris. Fervor . Poem. 20.
Hanna, Stanley. Men of Fortune . Poem. 20.
Sweitzer, Harry J. Denison and Education . Prose. 21.
Hopkins, Kate. Twillight . Prose. 23.
Hopkins, Kate. Afterward . Prose. 23
Science Forum: Consensus-based guidance for conducting and reporting multi-analyst studies
Any large dataset can be analyzed in a number of ways, and it is possible that the use of different analysis strategies will lead to different results and conclusions. One way to assess whether the results obtained depend on the analysis strategy chosen is to employ multiple analysts and leave each of them free to follow their own approach. Here, we present consensus-based guidance for conducting and reporting such multi-analyst studies, and we discuss how broader adoption of the multi-analyst approach has the potential to strengthen the robustness of results and conclusions obtained from analyses of datasets in basic and applied research
Clinical reappraisal of SHORT syndrome with PIK3R1 mutations: towards recommendation for molecular testing and management
International audienceSHORT syndrome has historically been defined by its acronym: short stature (S), hyperextensibility of joints and/or inguinal hernia (H), ocular depression (O), Rieger abnormality (R) and teething delay (T). More recently several research groups have identified PIK3R1 mutations as responsible for SHORT syndrome. Knowledge of the molecular etiology of SHORT syndrome has permitted a reassessment of the clinical phenotype. The detailed phenotypes of 32 individuals with SHORT syndrome and PIK3R1 mutation, including eight newly ascertained individuals, were studied to fully define the syndrome and the indications for PIK3R1 testing. The major features described in the SHORT acronym were not universally seen and only half (52%) had 4 or more of the classic features. The commonly observed clinical features of SHORT syndrome seen in the cohort included IUGR \textless 10(th) percentile, postnatal growth restriction, lipoatrophy and the characteristic facial gestalt. Anterior chamber defects and insulin resistance or diabetes were also observed but were not as prevalent. The less specific, or minor features of SHORT syndrome include teething delay, thin wrinkled skin, speech delay, sensorineural deafness, hyperextensibility of joints and inguinal hernia. Given the high risk of diabetes mellitus, regular monitoring of glucose metabolism is warranted. An echocardiogram, ophthalmological and hearing assessments are also recommended
Consensus-based guidance for conducting and reporting multi-analyst studies
International audienceAny large dataset can be analyzed in a number of ways, and it is possible that the use of different analysis strategies will lead to different results and conclusions. One way to assess whether the results obtained depend on the analysis strategy chosen is to employ multiple analysts and leave each of them free to follow their own approach. Here, we present consensus-based guidance for conducting and reporting such multi-analyst studies, and we discuss how broader adoption of the multi-analyst approach has the potential to strengthen the robustness of results and conclusions obtained from analyses of datasets in basic and applied research
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