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Polarimetric studies of pulsars at low radio frequencies provide important observational insights into the pulsar emission mechanism and beam models, and probe the properties of the magneto-ionic interstellar medium (ISM). Aperture arrays are the main form of next-generation low-frequency telescopes, including the Murchison Widefield Array (MWA). These require a distinctly different approach to data processing (e.g. calibration and beamforming) compared to traditional dish antennas. As the second paper of this series, we present a verification of the MWA’s pulsar polarimetry capability, using two bright southern pulsars, PSRs J0742–2822 and J1752–2806. Our observations simultaneously cover multiple frequencies (76–313 MHz) and were taken at multiple zenith angles (ZA) during a single night for each pulsar. We show that the MWA can be reliably calibrated for ZA ≲45° and frequencies ≲270 MHz. We present the polarimetric profiles for PSRs J0742–2822 and J1752–2806 at frequencies lower than 300 MHz for the first time, along with an analysis of the linear polarisation degree and pulse profile evolution with frequency. For PSR J0742–2822, the measured degree of linear polarisation shows a rapid decrease at low frequencies, in contrast with the generally expected trend, which can be attributed to depolarisation effects from small-scale, turbulent, magneto-ionic ISM components. This effect has not been widely explored for pulsars in general and will be further investigated in future work.
“Get up, stand up and live! That's a movement.” — Elisabeth Joris (Joris 2015b)
Are women's parties effective? More than 50 women's parties have emerged since 1990 in countries all over the world, contesting and winning seats in local, national, and regional legislatures. Although women's parties are not infrequent, appear in a variety of contexts, and advance common agendas related to inclusion and equality, we know very little about their experiences or whether they have been able to achieve their goals. In this article, Frauen Macht Politik (FraP!) is examined to consider whether and how women's parties present an avenue for advancing women's movement goals. The evidence shows that forming a party can help the movement to set the public agenda, can increase the attention paid to their issues, and can influence the formal institutions of politics. Many variables neglected elsewhere in the literature shape the ability of niche parties to affect the commitments of more established parties: the nature of the small party; its composition, intent, reach, and resources; its institutional context; and the boundaries of the organization. These features also determine the extent to which women's movements can use a political party to influence the representativeness of a political system.
Infections due to Campylobacter, Escherichia coli and Salmonella pose a significant health burden in Canada, resulting in major costs to the health care system and economic impacts due to lost productivity resulting from illness. Recent literature suggests that climate may play a role in the prevalence of these pathogens along the food chain. This study used integrated surveillance data to examine associations between weather variables, serving as a proxy for climate, in agricultural areas and Campylobacter, generic E. coli and Salmonella contamination on samples of beef, poultry and swine meat products in Canada. Various temperature metrics (average, maximum and variability) were correlated with Campylobacter prevalence along the food chain. The prevalence of E. coli and Salmonella was correlated with both precipitation and temperatures metrics; however, analysis for E. coli was limited to beef and swine meats at retail settings, because prevalence in other combinations approached 100%, which obviated further analysis. Campylobacter contamination in poultry and swine at abattoir and retail settings demonstrated a seasonal trend, with increased prevalence generally from June or July through November, compared to the baseline month of December. Based on these analyses, Campylobacter is the most likely foodborne bacteria studied whose occurrence in meat products is affected by climatic changes in Canada. An exploratory analysis of data at the provincial scale, using Ontario as an example, revealed similar directional relationships between climate and bacterial prevalence.
Introduction: Acute migraine headaches are common causes of presentation to the emergency department (ED). There is great variability in the efficacy of the available parenteral agents to manage pain, though triptans are among the recommended treatments. The objective of this systematic review was to update a previous review examining the effectiveness of parenteral agents for the treatment of acute migraine in the ED or equivalent acute care setting; our review examined pain management in emergency settings and assessed the effectiveness of triptan agents. Methods: A comprehensive search of 10 electronic databases and grey literature was conducted to supplement the previous systematic review. Two independent reviewers completed study selection, quality assessment, and data extraction. Any discrepancies were resolved by third party adjudication. Pain scale scores were analyzed using standardized mean difference (SMD) with 95% confidence intervals (CIs) calculated using a random effects model; heterogeneity (I2) was reported. Results: Titles and abstracts of 5039 unique studies were reviewed, of which, 51 studies were included. Sixty-four studies from the original review were included, resulting in a total of 115 included studies. Pain was measured within the ED or equivalent acute care setting using a variety of pain scales, most commonly the 0-10 cm or 100 mm visual analog scale. Four studies compared pain scores between patients receiving sumatriptan vs. other agents, of which, patients receiving sumatriptan reported higher pain scale scores (SMD = 0.53; 95% CI: 0.04, 1.02; I2 = 80%). In particular, patients receiving sumatriptan reported higher pain scale scores than patients receiving metoclopramide (SMD = 0.68; 95% CI: 0.31, 1.04; n = 1) or ketorolac (SMD = 1.39; 95% CI: 0.56, 2.21; n = 1). Overall, studies comparing anti-inflammatory agents (i.e., ketorolac or dexketoprofen) to other agents reported improved pain scale scores among patients receiving anti-inflammatory agents (SMD = -0.38; 95% CI: -0.73, -0.03; I2 = 66%; n = 5). Conclusion: Limited evidence suggests that patients treated with metoclopramide or anti-inflammatory agents experience greater pain reduction compared to patients treated with sumatriptan. This review will conduct a network analysis of parenteral agents to examine the comparative effectiveness of parenteral agents to manage pain among patients with acute migraine. Further analysis will also consider the balance between efficacy and adverse events.
Introduction: Although a variety of parenteral agents exist for the treatment of acute migraine, relapse after an emergency department (ED) visit is still a common occurrence. The objective of this systematic review was to update a previous review examining the effectiveness of parenteral agents for the treatment of acute migraine in the ED or equivalent acute care setting; our review focused on those studies aiming a reduction in relapse after an ED visit. Methods: A comprehensive search of 10 electronic databases and grey literature was conducted to identify comparative studies to supplement the previous systematic review. Two independent reviewers completed study selection, quality assessment, and data extraction. Any discrepancies were resolved by third party adjudication. Relative risks (RR) with 95% confidence intervals (CIs) were calculated using a random effects model and heterogeneity (I2) was reported. Results: Titles and abstracts of 5039 unique studies were reviewed, of which, 51 studies were included. Sixty-four studies from the original review were included, resulting in a total of 115 included studies. Relapse was reported in 44 (38%) included studies and occurred commonly in patients receiving placebo or no interventions (median = 39%; IQR: 14%, 47%). Overall, no differences in headache relapse were found between patients receiving sumatriptan or placebo (RR = 1.09; 95% CI: 0.55, 2.17; I2 = 93%; n = 8). Conversely, patients receiving neuroleptic agents experienced fewer relapses compared to placebo (RR = 0.27; 95% CI: 0.12, 0.58; I2 = 0%; n = 3); however, patients receiving neuroleptics reported an increase in adverse events (RR = 1.87; 95% CI: 1.17, 3.00; I2 = 0%; n = 3). Compared to placebo, patients receiving dexamethasone were less likely to experience a headache recurrence (RR = 0.71; 95% CI: 0.53, 0.95; I2 = 60%, n = 9); however, no differences were found in reported adverse events (RR = 1.09; 95% CI: 0.81, 1.47; I2 = 0%; n = 3). Conclusion: Relapse is a common occurrence for patients with migraine headaches. This review found patients receiving neuroleptics or dexamethasone experienced fewer headache recurrences. Conversely, triptan agents appear to have minimal effect on reducing the risk for headache recurrence following discharge from an acute care setting. Limited available data on adverse events is an important limitation to inform decision-making. Guidelines should be revised to reflect these results.
In 2014, the Southeastern Archaeological Conference (SEAC) conducted a sexual harassment survey of its membership. The survey's goal was to investigate whether sexual harassment had occurred among its members, and if so, to document the rate and demographics of harassment. Our findings include a high (66%) level of harassment, primarily among women, with an additional 13% of respondents reporting sexual assault. This article provides an overview of the survey and responses. Additionally, we analyze survey data aimed at capturing change over time in harassment and assault, correlation between field and non-field tasks and harassment and assault, and correlation between gender of supervisor and harassment and assault. We also discuss the effects of harassment and assault on careers. We conclude with suggestions for decreasing the rate of harassment and assault and urge professional archaeological organizations to document sexual harassment and assault to mitigate the effects on their members and on the discipline as a whole.
Children with CHD and acquired heart disease have unique, high-risk physiology. They may have a higher risk of adverse tracheal-intubation-associated events, as compared with children with non-cardiac disease.
Materials and methods
We sought to evaluate the occurrence of adverse tracheal-intubation-associated events in children with cardiac disease compared to children with non-cardiac disease. A retrospective analysis of tracheal intubations from 38 international paediatric ICUs was performed using the National Emergency Airway Registry for Children (NEAR4KIDS) quality improvement registry. The primary outcome was the occurrence of any tracheal-intubation-associated event. Secondary outcomes included the occurrence of severe tracheal-intubation-associated events, multiple intubation attempts, and oxygen desaturation.
A total of 8851 intubations were reported between July, 2012 and March, 2016. Cardiac patients were younger, more likely to have haemodynamic instability, and less likely to have respiratory failure as an indication. The overall frequency of tracheal-intubation-associated events was not different (cardiac: 17% versus non-cardiac: 16%, p=0.13), nor was the rate of severe tracheal-intubation-associated events (cardiac: 7% versus non-cardiac: 6%, p=0.11). Tracheal-intubation-associated cardiac arrest occurred more often in cardiac patients (2.80 versus 1.28%; p<0.001), even after adjusting for patient and provider differences (adjusted odds ratio 1.79; p=0.03). Multiple intubation attempts occurred less often in cardiac patients (p=0.04), and oxygen desaturations occurred more often, even after excluding patients with cyanotic heart disease.
The overall incidence of adverse tracheal-intubation-associated events in cardiac patients was not different from that in non-cardiac patients. However, the presence of a cardiac diagnosis was associated with a higher occurrence of both tracheal-intubation-associated cardiac arrest and oxygen desaturation.
We have explored the thermodynamics of compressed magnetized plasmas in laboratory experiments and we call these studies ‘magnetothermodynamics’. The experiments are carried out in the Swarthmore Spheromak eXperiment device. In this device, a magnetized plasma source is located at one end and at the other end, a closed conducting can is installed. We generate parcels of magnetized plasma and observe their compression against the end wall of the conducting cylinder. The plasma parameters such as plasma density, temperature and magnetic field are measured during compression using HeNe laser interferometry, ion Doppler spectroscopy and a linear
probe array, respectively. To identify the instances of ion heating during compression, a PV diagram is constructed using measured density, temperature and a proxy for the volume of the magnetized plasma. Different equations of state are analysed to evaluate the adiabatic nature of the compressed plasma. A three-dimensional resistive magnetohydrodynamic code (NIMROD) is employed to simulate the twisted Taylor states and shows stagnation against the end wall of the closed conducting can. The simulation results are consistent to what we observe in our experiments.
Exposure to child maltreatment has been shown to increase lifetime risk for substance use disorders (SUD). However, this has not been systematically examined among race/ethnic groups, for whom rates of exposure to assaultive violence and SUD differ. This study examined variation by race/ethnicity and gender in associations of alcohol (AUD), cannabis (CUD), and tobacco (TUD) use disorders with three types of childhood interpersonal violence (cIPV): physical abuse, sexual abuse, and witnessing parental violence.
Data from the National Epidemiologic Survey of Alcohol-Related Conditions-III (N: 36 309), a US nationally representative sample, was utilized to examine associations of DSM-5 AUD, CUD and TUD with cIPV among men and women of five racial/ethnic groups. Models were adjusted for additional risk factors (e.g. parental substance use problems, participant's co-occurring SUD).
Independent contributions of childhood physical and sexual abuse to AUD, CUD, and TUD, and of witnessing parental violence to AUD and TUD were observed. Associations of cIPV and SUD were relatively similar across race/ethnicity and gender [Odds Ratios (ORs) ranged from 1.1 to 1.9], although associations of physical abuse with AUD and TUD were greater among males, associations of parental violence and AUD were greater among females, and associations of parental violence with AUD were greater among Hispanic women and American Indian men.
Given the paucity of research in this area, and the potential identification of modifiable risk factors to reduce the impact of childhood interpersonal violence on SUDs, further research and consideration of tailoring prevention and intervention efforts to different populations are warranted.
The Murchison Widefield Array, and its recently developed Voltage Capture System, facilitates extending the low-frequency range of pulsar observations at high-time and -frequency resolution in the Southern Hemisphere, providing further information about pulsars and the ISM. We present the results of an initial time-resolved census of known pulsars using the Murchison Widefield Array. To significantly reduce the processing load, we incoherently sum the detected powers from the 128 Murchison Widefield Array tiles, which yields ~10% of the attainable sensitivity of the coherent sum. This preserves the large field-of-view (~450 deg2 at 185 MHz), allowing multiple pulsars to be observed simultaneously. We developed a WIde-field Pulsar Pipeline that processes the data from each observation and automatically folds every known pulsar located within the beam. We have detected 50 pulsars to date, 6 of which are millisecond pulsars. This is consistent with our expectation, given the telescope sensitivity and the sky coverage of the processed data (~17 000 deg2). For 10 pulsars, we present the lowest frequency detections published. For a subset of the pulsars, we present multi-frequency pulse profiles by combining our data with published profiles from other telescopes. Since the Murchison Widefield Array is a low-frequency precursor to the Square Kilometre Array, we use our census results to forecast that a survey using the low-frequency component of the Square Kilometre Array Phase 1 can potentially detect around 9 400 pulsars.
Thin-shelled, weakly articulated, epifaunal byssate to free-living flat clams characterize Devonian-Cretaceous dark, organic-rich shale facies. Convergent evolution on the flat-clam morph occurs among several families of Bivalvia. Flat clams regularly occurred in dense populations, dominating low diversity, inequitable communities for which they were commonly the pioneer species and formed shell islands for the colonization of smaller, firm-substrate dependent invertebrates. The unique flat-clam dominated ecosystem, as well as the widespread environments to which they were adapted, disappeared at the end of the Cretaceous. Although locally, low-oxygen benthic muds exist through the Cenozoic to Recent, they do not support large populations of flat clams, whose ecological niche was never filled after the Cretaceous. Flat clams underwent an exponential increase in size and apparent growth rates through the mid- and Late Cretaceous, reaching over 3 m in diameter (Inoceramidae). Most of this increase in shell size also involved expansion of mantle tissue and probably gills, relative to the size of the visceral mass. This suggests specific adaptations to colonization of oxygen-poor benthic habitats with hydrogensulfide enriched substrates, which broadly characterized Paleozoic and Mesozoic epicontinental seas, during greenhouse intervals. Such conditions were particularly well-developed during Cretaceous Oceanic Anoxic Events, at which time flat clams thrived.
Functional morphology, geochemistry, and facies associations suggest that many flat clams were chemosymbiotic and/or had greatly expanded oxygen-absorption surfaces. These adaptations allowed them to be opportunistic in chemically stressed benthic environments; growth rates also seem to be enhanced in these environments, a characteristic of living chemosymbiotic species. Many lines of evidence prove that flat clams lived in these environments and do not represent pseudoplanktic rain. A combination of factors seems to have been responsible for their disappearance near the end of the Cretaceous; i.e., mass extinction, loss of primary habitats, and major radiation among bottom-feeding bivalve predators.
Return visits to the emergency department (RTED) for the same clinical complaint occur in 2.7% to 8.1% of children presenting to pediatric emergency departments (PEDs). Most studies examining RTEDs have focused solely on PEDs and do not capture children returning to other local emergency departments (EDs). Our objective was to measure the frequency and characterize the directional pattern of RTED to any of 18 EDs serving a large geographic area for children initially evaluated at a PED.
We conducted a retrospective cohort study of all visits to a referral centre PED between August 2012 and August 2013. We compared demographic variables between children with and without an RTED, measures of flow and disposition outcomes between the initial (index) visit and RTED, and between RTED to the original PED versus to other EDs in the community.
Among all PED visits, 7.6% had an RTED within 7 days, of which 13% were to a facility other than the original PED. Children with an RTED had higher acuity and longer length of stay on their index visit. They were also more likely to be admitted on a subsequent visit than the overall PED population. RTED to the original PED had a longer waiting time (WT), length of stay, and more frequently resulted in hospitalization than RTED to a general ED.
A significant proportion of RTED occur at a site other than where the original ED visit occurred. Examining RTED to and from only PEDs underestimates its burden on emergency health services.
This paper reports the first successful synthesis and the structural characterization of nanocrystalline and stacking-disordered β-cristobalite AlPO4 that is chemically stabilized down to room temperature and free of crystalline impurity phases. Several batches of the title compound were synthesized and thoroughly characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy, selected area electron diffraction, energy dispersive X-ray spectroscopy mapping in SEM, solid-state 31P nuclear magnetic resonance (31P-NMR) spectroscopy including the TRAPDOR method, differential thermal analysis (DTA), gas-sorption methods, optical emission spectroscopy, X-ray fluorescence spectroscopy, and ion chromatography. Parameters that are critical for the synthesis were identified and optimized. The synthesis procedure yields reproducible results and is well documented. A high-quality XRD pattern of the title compound is presented, which was collected with monochromatic copper radiation at room temperature in a wide 2θ range of 5°–100°.
Leishmania amazonensis promastigotes are known to express furosemide (Lasix®)-sensitive P-type membrane Na+-ATPase. In the present study, furosemide activity was studied in intracellular amastigotes and infected BALB/c mice to investigate its efficacy in cutaneous leishmaniasis (CL). Intracellular parasites, but not macrophages, were found to be sensitive to killing by furosemide (IC50 = 87 µmvs CC50 ≫ 1000 µm, respectively). Although furosemide did not induce nitric oxide production or intracellular pH changes in infected macrophages, it led to a significant reactive oxygen species (ROS) burst. Freshly isolated tissue parasites expressed a high degree of Na+-ATPase activity that decreased with culture, indicative of a higher enzyme expression in amastigotes than in promastigotes. Both intraperitoneal and oral treatment of L. amazonensis-infected mice with furosemide dosages equivalent to that prescribed as a diuretic significantly reduced the parasite's growth compared with the situation in untreated mice. Combination with oral furosemide increased the efficacy and safety of intraperitoneal treatment with sodium stibogluconate (SSG). To summarize, furosemide control of intracellular leishmanial growth by means of parasite Na+-ATPase inhibition, and macrophage ROS activation may help explain its sole and SSG-combined therapeutic effect against murine CL.
Previous research on agriculture in the American Southwest focuses overwhelmingly on archaeological survey methods to discern surface agricultural features, which, in combination with climatological, geological, and geographical variables, are used to create models about agricultural productivity in the past. However, with few exceptions, the role of floodplain irrigation and floodwater farming in ancestral Pueblo agriculture is generally downplayed in scholarly discourse. Using a variety of methods, including Unmanned Aerial Vehicles (UAV), satellite imagery, pedestrian survey, and supervised classification of remotely sensed imagery, we examine this issue through a consideration of how ancestral Ohkay Owingeh (Tewa) people solved the challenges of arid land farming in the lower Rio Chama watershed of New Mexico during the Classic period (A.D. 1350–1598). Based on acreage estimates, our results indicate that runoff and rainwater fields in terrace environments would have been insufficient to supply the nutritional needs of an ancestral Tewa population exceeding 10,000 individuals. Based on these observations, we present a case for the substantial role of subsistence agriculture in the floodplain of the Rio Chama and its associated tributaries.