bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Blazar PG 1553+113 as a Binary System of Supermassive Black Holes
Authors: Tavani M. , Cavaliere A. , Munar-Adrover Pere , Argan A. 
Published: February 2018

Abstract
The BL Lac PG 1553+113 has been continuously monitored in gamma-rays with Fermi-LAT for over 9 years. Its updated light curve now includes five iterations of a main pattern comprising a high peak and a longer trough, with a period

. Our analysis of 2015–2017 data confirms the occurrence in 2017 January of a new peak fitting in with the previous trend. In addition, we identify secondary peaks (“twin peaks”) that occur in closely symmetric pairs on both sides of most main peaks, including the last one; their occurrence is supported by correlated X-ray outbursts. We stress that the above features strongly point to binary dynamics in a system of two black holes (BHs) of some 108 and

. At periastron the smaller BH periodically stresses the jet j
1 launched by the heavier companion, and triggers MHD–kinetic tearing instabilities. These lead to magnetic reconnections and to acceleration of electrons that produce synchrotron emission from the optical to X-ray bands, and inverse Compton scattering into the GeV range. We discuss two possible origins of the twin peaks : a single-jet model, based on added instabilities induced in j
1 by the smaller companion BH on its inner orbital arc; and a two-jet model with the smaller BH supporting its own, precessing jet j
2 that contributes lower, specific GeV emissions. Such behaviors combining time stability with amplitude variations betray plasma instabilities driven in either jet by binary dynamics, and can provide a double signature of the long-sought supermassive BH binaries.
Simulating Radio Emission from Low-mass Stars
Authors: Llama Joe , Jardine Moira M. , Wood Kenneth , Hallinan Gregg , Morin Julien 
Published: February 2018

Abstract
Understanding the origins of stellar radio emission can provide invaluable insight into the strength and geometry of stellar magnetic fields and the resultant space weather environment experienced by exoplanets. Here, we present the first model capable of predicting radio emission through the electron cyclotron maser instability using observed stellar magnetic maps of low-mass stars. We determine the structure of the coronal magnetic field and plasma using spectropolarimetric observations of the surface magnetic fields and the X-ray emission measure. We then model the emission of photons from the locations within the corona that satisfy the conditions for electron cyclotron maser emission. Our model predicts the frequency and intensity of radio photons from within the stellar corona. We have benchmarked our model against the low-mass star V374 Peg. This star has both radio observations from the Very Large Array and a nearly simultaneous magnetic map. Using our model we are able to fit the radio observations of V374 Peg, providing additional evidence that the radio emission observed from low-mass stars may originate from the electron cyclotron maser instability. Our model can now be extended to all stars with observed magnetic maps to predict the expected frequency and variability of stellar radio emission in an effort to understand and guide future radio observations of low-mass stars.
Stellar Population Synthesis of Star-forming Clumps in Galaxy Pairs and Non-interacting Spiral Galaxies
Authors: Zaragoza-Cardiel Javier , Smith Beverly J. , Rosado Margarita , Beckman John E. , Bitsakis Theodoros , Camps-Fariña Artemi , Font Joan , Cox Isaiah S. 
Published: February 2018

Abstract
We have identified 1027 star-forming complexes in a sample of 46 galaxies from the Spirals, Bridges, and Tails (SB&T) sample of interacting galaxies, and 693 star-forming complexes in a sample of 38 non-interacting spiral (NIS) galaxies in 8 μm observations from the Spitzer Infrared Array Camera. We have used archival multi-wavelength UV-to IR observations to fit the observed spectral energy distribution of our clumps with the Code Investigating GALaxy Emission using a double exponentially declined star formation history. We derive the star formation rates (SFRs), stellar masses, ages and fractions of the most recent burst, dust attenuation, and fractional emission due to an active galactic nucleus for these clumps. The resolved star formation main sequence holds on 2.5 kpc scales, although it does not hold on 1 kpc scales. We analyzed the relation between SFR, stellar mass, and age of the recent burst in the SB&T and NIS samples, and we found that the SFR per stellar mass is higher in the SB&T galaxies, and the clumps are younger in the galaxy pairs. We analyzed the SFR radial profile and found that the SFR is enhanced through the disk and in the tidal features relative to normal spirals.
Role of efflux pump and OprD porin expression in carbapenem resistance of Pseudomonas aeruginosa clinical isolates
Authors: Muderris Tuba , Durmaz Rıza , Ozdem Birsen , Dal Tuba , Unaldı Ozlem , Aydogan Sibel , Celikbilek Nevreste , Acıkgoz Ziya Cibali 
Published: February 2018

Introduction: In recent years, the prevalence of multidrug-resistant P. aeruginosa has remarkably increased. Thus, we wanted to investigate the carbapenem resistance mechanisms and clonal relationship among 80 carbapenem-resistant P. aeruginosa strains.
Methodology: Carbapenemase production was detected using the Modified Hodge Test (MHT), EDTA combined disc method (ECD), and PCR. Expression levels of efflux and porin genes were mesured by real-time reverse transcription PCR. Clonal relationship of the isolates was investigated by pulsed-field gel electrophoresis (PFGE).
Results: Carbapenemase production was detected in 7.5% of the isolates with MHT/ECD tests and in 11.3% of the isolates with PCR. Although the specificity of MHT/ECD was high, the sensitivitivity was low. oprD downregulation and mexB, mexY, and mexD overexpression were demonstrated in 55%, 16.3%, 2.5%, and 2.5% of the isolates, respectively. Multiple carbapenem resistance mechanisms were found in nearly a quarter of the isolates. PFGE typing of the 80 P. aeruginosa isolates yielded 61 different patterns. A total of 29 isolates (36.3%) were classified in 10 clusters, containing 2 to 7 strains. We could not find a strict relationship between PFGE profile and carbapenem resistance mechanisms.
Conclusions: Although oprD downregulation and MexAB-OprM overexpression were the most common mechanisms, carbapenem resistance was associated with multiple mechanisms in the study. MHT/ECD tests should not be used alone for investigation of carbapenemase production in P. aeruginosa. Rapid tests with high sensitivity and specificity should be developed for the detection of carbapenemase production in P. aeruginosa.
Molecular epidemiology of coronavirus in faeces of Brazilian calves and Peruvian camelid herds
Authors: Rocha Camila B , Fornells Luz Alba A.M.G. , Rojas Miguel , Libetal Maíra , Manchego Alberto , Pezo Danilo , Santos Norma 
Published: February 2018

Introduction: The enteric disorders represent a serious hazard for bovine and camelid breeding. The aim of this study was to examine the frequency of detection and molecular characteristics of enteric coronavirus (CoV) infections in cattle, alpaca, and llama herds bred in family-based farms in Brazil and Peru.
Methodology: Stool samples were collected from calves from Brazil and camelids from Peru for detection and characterization of CoV by reverse transcription polymerase chain reaction (RT-PCR) and sequence analysis.
Results: 46.5% (47/101) samples from calves and 26.8% (70/261) from alpaca tested positive for CoV. All strains belong to lineage A1 of the Betacoronavirus genus. Phylogenetic analysis showed high identity between CoV strains detected in calves and alpacas.
Conclusions: This study characterised CoV strains from dairy cattle herds in the state of Rio de Janeiro, Brazil, and indicated that this virus is spread among the state herds. The results also indicate widespread circulation of CoV among the alpacas of Cuzco, Peru.
Simultaneous assimilation of ozone profiles from multiple UV-VIS satellite instruments
Authors: van Peet Jacob C. A. , van der A Ronald J. , Kelder Hennie M. , Levelt Pieternel F. 
Published: February 2018

Abstract. A three-dimensional global ozone distribution has been derived from
assimilation of ozone profiles that were observed by satellites. By
simultaneous assimilation of ozone profiles retrieved from the nadir
looking satellite instruments Global Ozone Monitoring Experiment 2
(GOME-2) and Ozone Monitoring Instrument (OMI), which measure the
atmosphere at different times of the day, the quality of the derived
atmospheric ozone field has been improved. The assimilation is using
an extended Kalman filter in which chemical transport model TM5 has
been used for the forecast. The combined assimilation of both GOME-2
and OMI improves upon the assimilation results of a single
sensor. The new assimilation system has been demonstrated by
processing 4 years of data from 2008 to 2011. Validation of the
assimilation output by comparison with sondes shows that biases vary
between −5 and +10 % between the surface and
100 hPa. The biases for the combined assimilation vary
between −3 and +3 % in the region between 100 and
10 hPa where GOME-2 and OMI are most sensitive. This is
a strong improvement compared to direct retrievals of ozone profiles
from satellite observations.
Characterization of atmospheric trace gases and particulate matter in Hangzhou, China
Authors: Zhang Gen , Xu Honghui , Qi Bing , Du Rongguang , Gui Ke , Wang Hongli , Jiang Wanting , Liang Linlin , Xu Wanyun 
Published: February 2018

Abstract. The Yangtze River Delta (YRD) is one of the most densely populated regions in China with severe air quality issues that have not been fully understood. Thus, in this study, based on 1-year (2013) continuous measurement at a National Reference Climatological Station (NRCS, 30.22° N, 120.17° E; 41.7 m a.s.l.) in the center of Hangzhou in the YRD, we investigated the seasonal characteristics, interspecies relationships, and the local emissions and the regional potential source contributions of trace gases (including O3, NOx, NOy, SO2, and CO) and particulate matter (PM2.5 and PM10). Results revealed that severe two-tier air pollution (photochemical and haze pollution) occurred in this region, with frequent exceedances in O3 (38 days) and PM2.5 (62 days). O3 and PM2.5 both exhibited distinct seasonal variations with reversed patterns: O3 reaching a maximum in warm seasons (May and July) but PM2.5 reaching a maximum in cold seasons (November to January). The overall results from interspecies correlation indicated a strong local photochemistry favoring the O3 production under a volatile organic compound (VOC)-limited regime, whereas it moved towards an optimum O3 production zone during warm seasons, accompanied by the formation of secondary fine particulates under high O3. The emission maps of PM2.5, CO, NOx, and SO2 demonstrated that local emissions were significant for these species on a seasonal scale. The contributions from the regional transport among inland cities (Zhejiang, Jiangsu, Anhui, and Jiangxi Province) on a seasonal scale were further confirmed to be crucial to air pollution at the NRCS site by using backward trajectory simulations. Air masses transported from the offshore areas of the Yellow Sea, East Sea, and South Sea were also found to be highly relevant to the elevated O3 at the NRCS site through the analysis of potential source contribution function (PSCF). Case studies of photochemical pollution (O3) and haze (PM2.5) episodes both suggested the combined importance of local atmospheric photochemistry and synoptic conditions during the accumulation (related with anticyclones) and dilution process (related with cyclones). Apart from supplementing a general picture of the air pollution state in the city of Hangzhou in the YRD region, this study specifically elucidates the role of local emission and regional transport, and it interprets the physical and photochemical processes during haze and photochemical pollution episodes. Moreover, this work suggests that cross-regional control measures are crucial to improve air quality in the YRD region, and it further emphasizes the importance of local thermally induced circulation for air quality.
Photosynthesis–irradiance parameters of marine phytoplankton: synthesis of a global data set
Authors: Bouman Heather A. , Platt Trevor , Doblin Martina , Figueiras Francisco G. , Gudmundsson Kristinn , Gudfinnsson Hafsteinn G. , Huang Bangqin , Hickman Anna , Hiscock Michael , Jackson Thomas , Lutz Vivian A. , Mélin Frédéric , Rey Francisco , Pepin Pierre , Segura Valeria , Tilstone Gavin H. , van Dongen-Vogels Virginie , Sathyendranath Shubha 
Published: February 2018

Abstract. The photosynthetic performance of marine phytoplankton varies in response to a variety of factors, environmental and taxonomic. One of the aims of the MArine primary Production: model Parameters from Space (MAPPS) project of the European Space Agency is to assemble a global database of photosynthesis–irradiance (P-E) parameters from a range of oceanographic regimes as an aid to examining the basin-scale variability in the photophysiological response of marine phytoplankton and to use this information to improve the assignment of P-E parameters in the estimation of global marine primary production using satellite data. The MAPPS P-E database, which consists of over 5000 P-E experiments, provides information on the spatio-temporal variability in the two P-E parameters (the assimilation number, PmB, and the initial slope, αB, where the superscripts B indicate normalisation to concentration of chlorophyll) that are fundamental inputs for models (satellite-based and otherwise) of marine primary production that use chlorophyll as the state variable. Quality-control measures consisted of removing samples with abnormally high parameter values and flags were added to denote whether the spectral quality of the incubator lamp was used to calculate a broad-band value of αB. The MAPPS database provides a photophysiological data set that is unprecedented in number of observations and in spatial coverage. The database will be useful to a variety of research communities, including marine ecologists, biogeochemical modellers, remote-sensing scientists and algal physiologists. The compiled data are available at https://doi.org/10.1594/PANGAEA.874087 (Bouman et al., 2017).
Hydrological characterization of cave drip waters in a porous limestone: Golgotha Cave, Western Australia
Authors: Mahmud Kashif , Mariethoz Gregoire , Baker Andy , Treble Pauline C. 
Published: February 2018

Abstract. Cave drip water response to surface meteorological conditions is
complex due to the heterogeneity of water movement in the karst unsaturated
zone. Previous studies have focused on the monitoring of fractured rock
limestones that have little or no primary porosity. In this study, we aim to
further understand infiltration water hydrology in the Tamala Limestone of
SW Australia, which is Quaternary aeolianite with primary porosity. We build on
our previous studies of the Golgotha Cave system and utilize the existing
spatial survey of 29 automated cave drip loggers and a lidar-based flow
classification scheme, conducted in the two main chambers of this cave. We
find that a daily sampling frequency at our cave site optimizes the capture
of drip variability with the least possible sampling artifacts. With the optimum
sampling frequency, most of the drip sites show persistent autocorrelation
for at least a month, typically much longer, indicating ample storage of
water feeding all stalactites investigated. Drip discharge histograms are
highly variable, showing sometimes multimodal distributions. Histogram
skewness is shown to relate to the wetter-than-average 2013 hydrological year
and modality is affected by seasonality. The hydrological classification
scheme with respect to mean discharge and the flow variation can distinguish
between groundwater flow types in limestones with primary porosity, and the
technique could be used to characterize different karst flow paths when
high-frequency automated drip logger data are available. We observe little
difference in the coefficient of variation (COV) between flow classification
types, probably reflecting the ample storage due to the dominance of primary
porosity at this cave site. Moreover, we do not find any relationship between
drip variability and discharge within similar flow type. Finally, a
combination of multidimensional scaling (MDS) and clustering by k means is
used to classify similar drip types based on time series analysis. This
clustering reveals four unique drip regimes which agree with previous flow
type classification for this site. It highlights a spatial homogeneity in
drip types in one cave chamber, and spatial heterogeneity in the other, which
is in agreement with our understanding of cave chamber morphology and lithology.
Development of Hospice and Palliative Medicine Knowledge and Skills for Emergency Medicine Residents: Using the Accreditation Council for Graduate Medical Education Milestone Framework
Authors: Shoenberger Jan , Lamba Sangeeta , Goett Rebecca , DeSandre Paul , Aberger Kate , Bigelow Suzanne , Brandtman Todd , Chan Garrett K. , Zalenski Robert , Wang David , Rosenberg Mark , Jubanyik Karen 
Published: February 2018

AbstractObjectivesEmergency medicine (EM) physicians commonly care for patients with serious life‐limiting illness. Hospice and palliative medicine (HPM) is a subspecialty pathway of EM. Although a subspecialty level of practice requires additional training, primary‐level skills of HPM such as effective communication and symptom management are part of routine clinical care and expected of EM residents. However, unlike EM residency curricula in disciplines like trauma and ultrasound, there is no nationally defined HPM curriculum for EM resident training. An expert consensus group was convened with the aim of defining content areas and competencies for HPM primary‐level practice in the ED setting. Our overall objective was to develop HPM milestones within a competency framework that is relevant to the practice of EM.MethodsThe American College of Emergency Physicians Palliative Medicine Section assembled a committee that included academic EM faculty, community EM physicians, EM residents, and nurses, all with interest and expertise in curricular design and palliative medicine.ResultsThe committee peer reviewed and assessed HPM content for validity and importance to EM residency training. A topic list was developed with three domains: provider skill set, clinical recognition of HPM needs, and logistic understanding related to HPM in the ED. The group also developed milestones in HPM‐EM to identify relevant knowledge, skills, and behaviors using the framework modeled after the Accreditation Council for Graduate Medical Education (ACGME) EM milestones. This framework was chosen to make the product as user‐friendly and familiar as possible to facilitate use by EM educators.ConclusionsEducators in EM residency programs now have access to HPM content areas and milestones relevant to EM practice that can be used for curriculum development in EM residency programs. The HPM‐EM skills/competencies presented herein are structured in a familiar milestone framework that is modeled after the widely accepted ACGME EM milestones.
Meta-analysis of mortality in patients with high-risk intraductal papillary mucinous neoplasms under observation
Authors: Vanella G. , Crippa S. , Archibugi L. , Arcidiacono P. G. , Delle Fave G. , Falconi M. , Capurso G. 
Published: February 2018

Abstract

Background
Although consensus guidelines suggest that patients with high-risk intraductal papillary mucinous neoplasms (IPMNs) should have surgery, a non-operative strategy is often selected in patients who are poor surgical candidates. The aim was to determine the risk of disease-related death from IPMN in patients with worrisome features or high-risk stigmata who were kept under observation.

Methods
A PubMed literature search was undertaken of articles published from August 1992 to June 2016 (updated October 2017). The methodology was developed from PRISMA and MOOSE checklists. Incidence proportions and rates of overall and IPMN-related deaths were calculated, with subgroup analyses for main-duct/mixed-type and branch-duct IPMNs. Quality of the studies, publication bias and heterogeneity were explored.

Results
Six studies reported data on overall mortality and eight described disease-specific mortality for 556 patients during follow-up ranging from 24·9 to 60·0 months. Pooled rates of overall and IPMN-related mortality were 30·9 (95 per cent c.i. 19·6 to 45·1) and 11·6 (6·0 to 21·2) per cent respectively. The pooled incidence rate for overall mortality was substantially higher than that for IPMN-related mortality: 78 (95 per cent c.i. 44 to 111) and 23 (9 to 37) per 1000 patient-years respectively. The pooled incidence rate for disease-specific mortality was considerably lower for branch-duct than for main-duct or mixed-type IPMNs: 5 (0 to 10) and 32 (12 to 52) per 1000 patient-years respectively.

Conclusion
In patients unfit for surgery, IPMN-related mortality among patients with worrisome features and high-risk stigmata is low, and the risk of death from other causes much higher.
Randomized clinical trial of intraoperative parathyroid gland angiography with indocyanine green fluorescence predicting parathyroid function after thyroid surgery
Authors: Vidal Fortuny J. , Sadowski S. M. , Belfontali V. , Guigard S. , Poncet A. , Ris F. , Karenovics W. , Triponez F. 
Published: February 2018

Abstract

Background
Hypoparathyroidism, the most common complication after thyroid surgery, leads to hypocalcaemia and significant medical problems. An RCT was undertaken to determine whether intraoperative parathyroid gland angiography with indocyanine green (ICG) could predict postoperative hypoparathyroidism, and obviate the need for systematic blood tests and oral calcium supplementation.

Methods
Between September 2014 and February 2016, patients who had at least one well perfused parathyroid gland on ICG angiography were randomized to receive standard follow-up (measurement of calcium and parathyroid hormone (PTH) on postoperative day (POD) 1 and systematic supplementation with calcium and vitamin D; control group) or no supplementation and no blood test on POD 1 (intervention group). In all patients, calcium and PTH levels were measured 10–15 days after thyroidectomy. The primary endpoint was hypocalcaemia on POD 10–15.

Results
A total of 196 patients underwent ICG angiography during thyroid surgery, of whom 146 had at least one well perfused parathyroid gland on ICG angiography and were randomized. None of these patients presented with hypoparathyroidism, including those who did not receive calcium supplementation. The intervention group was statistically non-inferior to the control group (exact 95 per cent c.i. of the difference in proportion of patients with hypocalcaemia –0·053 to 0·053; P = 0·012). Eleven of the 50 excluded patients, in whom no well perfused parathyroid gland could be identified by angiography, presented with hypoparathyroidism on POD 1, and six on POD 10–15, which was significantly different from the findings in randomized patients (P = 0·007).

Conclusion
ICG angiography reliably predicts the vascularization of the parathyroid glands and obviates the need for postoperative measurement of calcium and PTH, and supplementation with calcium in patients with at least one well perfused parathyroid gland. Registration number: NCT02249780 (http://www.clinicaltrials.gov).