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Contiguous US summer maximum temperature and heat stress trends in CRU and NOAA Climate Division data plus comparisons to reanalyses.
Warming is a major climate change concern, but the impact of high maximum temperatures depends upon the air's moisture content. Trends in maximum summertime temperature, moisture, and heat index are tracked over three time periods: 1900-2011, 1950-2011, and 1979-2011; these trends differ notably from annual temperature trends. Trends are emphasized from two CRU datasets (CRUTS3.25 and CRUTS4.01) and two reanalyses (ERA-20C and 20CRv2). Maximum temperature trends tend towards warming that is stronger over the Great Lakes, the interior western and the northeastern contiguous United States. A warming hole in the Midwest generally decreases in size and magnitude when heat stress trends are calculated because the region has increasing moisture. CRU and nearly all reanalyses find cooling in the northern high plains that is not found in NOAA Climate Division trends. These NOAA trends are captured better by CRUTS401. Moistening in the northeast amplifies the heat stress there. Elsewhere the moisture trends are less clear. Drying over northern Texas (after 1996) in CRUTS401 translates into decreasing heat stress there (less so in CRUTS325). Though other reanalyses are not intended for long-term trends, MERRA-2 and ERA-Interim match observed trends better than other reanalyses
Optimizing the MapReduce Framework on Intel Xeon Phi Coprocessor
With the ease-of-programming, flexibility and yet efficiency, MapReduce has
become one of the most popular frameworks for building big-data applications.
MapReduce was originally designed for distributed-computing, and has been
extended to various architectures, e,g, multi-core CPUs, GPUs and FPGAs. In
this work, we focus on optimizing the MapReduce framework on Xeon Phi, which is
the latest product released by Intel based on the Many Integrated Core
Architecture. To the best of our knowledge, this is the first work to optimize
the MapReduce framework on the Xeon Phi.
In our work, we utilize advanced features of the Xeon Phi to achieve high
performance. In order to take advantage of the SIMD vector processing units, we
propose a vectorization friendly technique for the map phase to assist the
auto-vectorization as well as develop SIMD hash computation algorithms.
Furthermore, we utilize MIMD hyper-threading to pipeline the map and reduce to
improve the resource utilization. We also eliminate multiple local arrays but
use low cost atomic operations on the global array for some applications, which
can improve the thread scalability and data locality due to the coherent L2
caches. Finally, for a given application, our framework can either
automatically detect suitable techniques to apply or provide guideline for
users at compilation time. We conduct comprehensive experiments to benchmark
the Xeon Phi and compare our optimized MapReduce framework with a
state-of-the-art multi-core based MapReduce framework (Phoenix++). By
evaluating six real-world applications, the experimental results show that our
optimized framework is 1.2X to 38X faster than Phoenix++ for various
applications on the Xeon Phi
LOW TEMPERATURE BATTERY MONITORING AND CONTROL SYSTEM – LITHIUM-ION LOW TEMPERATURE CASE STUDY
This open-ended research project, co-advised by Dr. Prodanov and Dr. Dolan, studies electronic and battery failures at low temperatures (between -70 ºC to 0 ºC). The main battery technology used for this project is Lithium-ion. The research project consists of two systems: the monitoring system and the actuating system. This project accomplishes the first part and assesses the feasibility of measuring the internal impedances of batteries for low-Earth-orbit (LEO) satellites as a means to monitor battery health. It also monitors the effects caused by low temperature conditions through internal impedance measurements from 0 ºC through -70 °C. It includes designing a compact system prototype having dimensions smaller than 16” x 11” x 11.75” and a total weight less than 10% of the battery weight
Provenance for the people: an HCI perspective on the W3C PROV standard through an online game
In the information age, tools for examining the validity of data are invaluable. Provenance is one such tool, and the PROV model proposed by the World Wide Web Consortium in 2013 offers a means of expressing provenance in a machine readable format. In this paper, we examine from a user’s standpoint notions of provenance, the accessibility of the PROV model, and the general attitudes towards history and the verifiability of information in modern data society. We do this through the medium of an online-game designed to explore these issues and present the findings of the study along with a discussion of some of its implications
Catalyzing collaborations: Prescribed interactions at conferences determine team formation
Collaboration plays a key role in knowledge production. Here, we show that
patterns of interaction during conferences can be used to predict who will
subsequently form a new collaboration, even when interaction is prescribed
rather than freely chosen. We introduce a novel longitudinal dataset tracking
patterns of interaction among hundreds of scientists during multi-day
conferences encompassing different scientific fields over the span of 5 years.
We find that participants who formed new collaborations interacted 63% more on
average than those who chose not to form new teams, and that those assigned to
a higher interaction scenario had more than an eightfold increase in their odds
of collaborating. We propose a simple mathematical framework for the process of
team formation that incorporates this observation as well as the effect of
memory beyond interaction time. The model accurately reproduces the
collaborations formed across all conferences and outperforms seven other
candidate models. This work not only suggests that encounters between
individuals at conferences play an important role in shaping the future of
science, but that these encounters can be designed to better catalyze
collaborations.Comment: 8 pages and 4 figures, main text; 8 pages and 3 figures supplementary
informatio
Cytomorphology of Circulating Colorectal Tumor Cells:A Small Case Series
Several methodologies exist to enumerate circulating tumor cells (CTCs) from the blood of cancer patients; however, most methodologies lack high-resolution imaging, and thus, little is known about the cytomorphologic features of these cells. In this study of metastatic colorectal cancer patients, we used immunofluorescent staining with fiber-optic array scanning technology to identify CTCs, with subsequent Wright-Giemsa and Papanicolau staining. The CTCs were compared to the corresponding primary and metastatic tumors. The colorectal CTCs showed marked intrapatient pleomorphism. In comparison to the corresponding tissue biopsies, cells from all sites showed similar pleomorphism, demonstrating that colorectal CTCs retain the pleomorphism present in regions of solid growth. They also often retain particular cytomorphologic features present in the patient's primary and/or metastatic tumor tissue. This study provides an initial analysis of the cytomorphologic features of circulating colon cancer cells, providing a foundation for further investigation into the significance and metastatic potential of CTCs
Feasibility of gadoxetate disodium enhanced 3D T1 MR cholangiography (MRC) with a specific inversion recovery prepulse for the assessment of the hepatobiliary system
Aim: To compare the potential of a gadoxetate disodium enhanced navigator-triggered 3D T1 magnetic-resonance cholangiography (MRC) sequence with a specific inversion recovery prepulse to T2-weighted MRCP for assessment of the hepatobiliary system.
Materials and methods: 30 patients (12 male, 18 female) prospectively underwent conventional navigator-triggered 3D turbo spin-echo T2-weighted MRCP and 3D T1 MRC with a specific inversion pulse to minimise signal from the liver 30 minutes after administration of gadoxetate disodium on a 1.5 T MRI system. For qualitative evaluation, biliary duct depiction was assessed segmentally following a 5-point Likert scale. Visualisation of hilar structures as well as image quality was recorded. Additionally, the extrahepatic bile ducts were assessed quantitatively by calculation of signal-to-noise ratios (SNR).
Results: The advantages of T1 3D MRC include reduced affection of image quality by bowel movement and robust depiction of the relative position of the extrahepatic bile ducts in relation to the portal vein and the duodenum compared to T2 MRCP. However, overall T1 3D MRC did not significantly (p > 0.05) improve the biliary duct depiction compared to T2 MRCP in all segments: Common bile duct 4.1 vs. 4.4, right hepatic duct 3.6 vs. 4.2, left hepatic duct 3.5 vs. 4.1. Image quality did not differ significantly (p > 0.05) between both sequences (3.6 vs. 3.5). SNR measurements for the hepatobiliary system did not differ significantly (p > 0.05) between navigator-triggered T1 3D MRC and T2 MRCP.
Conclusions: This preliminary study demonstrates that T1 3D MRC of a specific inversion recovery pre-pulse has potential to complement T2 MRCP, especially for the evaluation of liver structures close to the hilum in the diagnostic work-up of the biliary system in patients receiving gadoxetate disodium
Molecular Gas in the z=1.2 Ultraluminous Merger GOODS J123634.53+621241.3
We report the detection of CO(2-1) emission from the z=1.2 ultraluminous
infrared galaxy (ULIRG) GOODS J123634.53+621241.3 (also known as the
sub-millimeter galaxy GN26). These observations represent the first discovery
of high-redshift CO emission using the new Combined Array for Research in
Millimeter-Wave Astronomy (CARMA). Of all high-redshift (z>1) galaxies within
the GOODS-North field, this source has the largest far-infrared (FIR) flux
observed in the Spitzer 70um and 160um bands. The CO redshift confirms the
optical identification of the source, and the bright CO(2-1) line suggests the
presence of a large molecular gas reservoir of about 7x10^10 M(sun). The
infrared-to-CO luminosity ratio of L(IR)/L'(CO) = 80+/-30 L(sun) (K Km/s
pc^2)^-1 is slightly smaller than the average ratio found in local ULIRGs and
high-redshift sub-millimeter galaxies. The short star-formation time scale of
about 70 Myr is consistent with a starburst associated with the merger event
and is much shorter than the time scales for spiral galaxies and estimates made
for high-redshift galaxies selected on the basis of their B-z and z-K colors.Comment: Accepted for publication in ApJ Letter
Autoimmunity in the Pathogenesis and Treatment of Keratoconjunctivitis Sicca
Dry eye is a chronic corneal disease that impacts the quality of life of many older adults. keratoconjunctivitis sicca (KCS), a form of aqueous-deficient dry eye, is frequently associated with Sjögren’s syndrome and mechanisms of autoimmunity. For KCS and other forms of dry eye, current treatments are limited, with many medications providing only symptomatic relief rather than targeting the pathophysiology of disease. Here, we review proposed mechanisms in the pathogenesis of autoimmune-based KCS: genetic susceptibility and disruptions in antigen recognition, immune response, and immune regulation. By understanding the mechanisms of immune dysfunction through basic science and translational research, potential drug targets can be identified. Finally, we discuss current dry eye therapies as well as promising new treatment options and drug therapy targets
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