472 research outputs found
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Expert and operator perspectives on barriers to energy efficiency in data centers
It was last estimated in 2016 that data centers (DCs) comprise approximately 2% of total US electricity consumption. However, this estimate is currently being updated to account for the massive increase in computing needs due to streaming, cryptocurrency, and artificial intelligence (AI). To prevent energy consumption that tracks with increasing computing needs, it is imperative we identify energy efficiency strategies and investments beyond the low-hanging fruit solutions. In a two-phased research approach, we ask: What non-technical barriers still impede energy efficiency (EE) practices and investments in the data center sector, and what can be done to overcome these barriers? In particular, we are focused on social and organizational barriers to EE. In Phase I, we performed a literature review and found that technical solutions are abundant in the literature, but fail to address the top-down cultural shifts that need to take place in order to adapt new energy efficiency strategies. In Phase II, reported here, we interviewed 16 data center operators/experts to ground-truth our literature findings. Our interview protocols focus on three aspects of DC decision-making: procurement practices, metrics and monitoring, and perceived barriers to energy efficiency. We find that vendors are the key drivers of procurement decisions, advanced efficiency metrics are facility-specific, and there is convergence in the design of advanced facilities due to the heat density of parallelized infrastructure. Our ultimate goals for our research are to design DC decarbonization policies that target organizational structure, empower individual staff, and foster a supportive external market
Viral forensic genomics reveals the relatedness of classic herpes simplex virus strains KOS, KOS63, and KOS79
Herpes simplex virus 1 (HSV-1) is a widespread global pathogen, of which the strain KOS is one of the most extensively studied. Previous sequence studies revealed that KOS does not cluster with other strains of North American geographic origin, but instead clustered with Asian strains. We sequenced a historical isolate of the original KOS strain, called KOS63, along with a separately isolated strain attributed to the same source individual, termed KOS79. Genomic analyses revealed that KOS63 closely resembled other recently sequenced isolates of KOS and was of Asian origin, but that KOS79 was a genetically unrelated strain that clustered in genetic distance analyses with HSV-1 strains of North American/European origin. These data suggest that the human source of KOS63 and KOS79 could have been infected with two genetically unrelated strains of disparate geographic origins. A PCR RFLP test was developed for rapid identification of these strains
Examining a Peak-Luminosity/Decline-Rate Relationship for Tidal Disruption Events
We compare the luminosity, radius, and temperature evolution of the
UV/optical blackbodies for 21 well-observed tidal disruption events (TDEs), 8
of which were discovered by the All-Sky Automated Survey for Supernovae. We
find that the blackbody radii generally increase prior to peak and slowly
decline at late times. The blackbody temperature evolution is generally flat,
with a few objects showing small-scale variations. The bolometric UV/optical
luminosities generally evolve smoothly and flatten out at late times. Finally,
we find an apparent correlation between the peak luminosity and the decline
rate of TDEs. This relationship is strongest when comparing the peak luminosity
to its decline over 40 days. A linear fit yields in cgs, where
.Comment: 10 pages, 4 figures. Updated to reflect changes made in the published
ApJL version. Six new objects added to sample. Updated video description can
be found at https://youtu.be/TtZU22eyHv
Revealing AGNs Through TESS Variability
We used Transiting Exoplanet Survey Satellite (TESS) data to identify 29
candidate active galactic nuclei (AGNs) through their optical variability. The
high-cadence, high-precision TESS light curves present a unique opportunity for
the identification of AGNs, including those not selected through other methods.
Of the candidates, we found that 18 have either previously been identified as
AGNs in the literature or could have been selected based on emission-line
diagnostics, mid-IR colors, or X-ray luminosity. AGNs in low-mass galaxies
offer a window into supermassive black hole (SMBH) and galaxy co-evolution and
8 of the 29 candidates have estimated black hole masses . The low-mass galaxies NGC 4395 and NGC 4449 are two of our
five "high-confidence" candidates. By applying our methodology to the entire
TESS main and extended mission datasets, we expect to identify 45 more
AGN candidates, of which 26 will be new and 8 will be in low-mass
galaxies.Comment: 21 pages, 17 figures, 6 tables. Will be submitted to AAS journals.
Comments welcom
Chandra, HST/STIS, NICER, Swift, and TESS Detail the Flare Evolution of the Repeating Nuclear Transient ASASSN-14ko
ASASSN-14ko is a nuclear transient at the center of the AGN ESO 253-G003 that
undergoes periodic flares. Optical flares were first observed in 2014 by the
All-Sky Automated Survey for Supernovae (ASAS-SN) and their peak times are
well-modeled with a period of days and period derivative
of . Here we present ASAS-SN, Chandra, HST/STIS, NICER,
Swift, and TESS data for the flares that occurred in December 2020, April 2021,
July 2021, and November 2021. The HST/STIS UV spectra evolve from blue shifted
broad absorption features to red shifted broad emission features over 10
days. The Swift UV/optical light curves peaked as predicted by the timing
model, but the peak UV luminosities varied between flares and the UV flux in
July 2021 was roughly half the brightness of all other peaks. The X-ray
luminosities consistently decreased and the spectra became harder during the
UV/optical rise but apparently without changes in absorption. Finally, two
high-cadence TESS light curves from December 2020 and November 2018 showed that
the slopes during the rising and declining phases changed over time, which
indicates some stochasticity in the flare's driving mechanism. ASASSN-14ko
remains observationally consistent with a repeating partial tidal disruption
event, but, these rich multi-wavelength data are in need of a detailed
theoretical model.Comment: 25 pages, 14 figures, 4 tables; Submitted to ApJ, comments welcom
An exploratory study looking at the relationship marketing techniques used in the music festival industry
There are current issues and trends in the music festival
market, which may affect the success of an event, and market saturation
is at the forefront of these issues. Previous literature, maintaining
the need for a marketing approach to festivals, identifi es the need
for maintaining strong stakeholder relationships in order to succeed
in a business environment; attention has been focused to the theory
of relationship marketing (RM) because of the recognition that this
practice is complementary to the marketing of festivals. The very nature
of the music festival as an annual, usually, 4-day event means that
effective marketing is needed to keep connections with the consumer
throughout the year. This article focuses on the RM techniques
utilised within the music festival industry from the viewpoint of the
festival organiser in an attempt to establish how festival organisations
value and monitor organisational relationships. This article explores
the extent to which these relationships are valued and managed;
furthermore, the variations between these intricate relationships
are considered by focusing on those held with the organisation ’ s
consumers and sponsors, the results of which have provided the
ability to establish the importance and relevance of RM to the industry
and further identify the marketing communication methods employed
to establish and maintain such relationships. In-depth, convergent
interviews have been conducted with a segment of music festival
organisers from a range of events. The results have been integrated
with the study of current literature to best exemplify these issues. It
has been established that RM has a strong role in today ’ s commercial
and independent music festival industry; technological advances are
enabling the organiser to support online relationships further and
increase consumer loyalty. There is a need to expand the research
further because of the complexity of organisational relationships and
the varying categories of festivals
ABRF Proteome Informatics Research Group (iPRG) 2016 Study: Inferring Proteoforms from Bottom-up Proteomics Data.
This report presents the results from the 2016 Association of Biomolecular Resource Facilities Proteome Informatics Research Group (iPRG) study on proteoform inference and false discovery rate (FDR) estimation from bottom-up proteomics data. For this study, 3 replicate Q Exactive Orbitrap liquid chromatography-tandom mass spectrometry datasets were generated from each of
Biological controls for standardization and interpretation of adaptive immune receptor repertoire profiling
Use of adaptive immune receptor repertoire sequencing (AIRR-seq) has become widespread, providing new insights into the immune system with potential broad clinical and diagnostic applications. However, like many high-throughput technologies, it comes with several problems, and the AIRR Community was established to understand and help solve them. We, the AIRR Community's Biological Resources Working Group, have surveyed scientists about the need for standards and controls in generating and annotating AIRR-seq data. Here, we review the current status of AIRR-seq, provide the results of our survey, and based on them, offer recommendations for developing AIRR-seq standards and controls, including future work.
Keywords: B-cell Receptor (BCR); IG; T-cell Receptor (TCR); TR; antibody; immunoglobulin; immunology; inflammation; next generation sequencing (NGS)
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