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Delayed presentation to the emergency department influences acute stroke care and can result in worse outcomes. Despite public health messaging, many young adults consider stroke as a disease of older people. We determined the differences in ambulance utilization and delays to hospital presentation between women and men as well as younger (18–44 years) versus older (≥45 years) patients with stroke.
We conducted a population-based retrospective study using national administrative health data from the Canadian Institute of Health Information databases and examined data between 2003 and 2016 to compare ambulance utilization and time to hospital presentation across sex and age.
Young adults account for 3.9% of 463,310 stroke/transient ischemic attack/hemorrhage admissions. They have a higher proportion of hemorrhage (37% vs. 15%) and fewer ischemic events (50% vs. 68%) compared with older patients. Younger patients are less likely to arrive by ambulance (62% vs. 66%, p < 0.001), with younger women least likely to use ambulance services (61%) and older women most likely (68%). Median stroke onset to hospital arrival times were 7 h for older patients and younger men, but 9 h in younger women. There has been no improvement among young women in ambulance utilization since 2003, whereas ambulance use increased in all other groups.
Younger adults, especially younger women, are less likely to use ambulance services, take longer to get to hospital, and have not improved in utilization of emergency services for stroke over 13 years. Targeted public health messaging is required to ensure younger adults seek emergency stroke care.
Limited evidence supports primary care paramedic (PCP) direct transport of ST-segment elevation myocardial infarction (STEMI) patients for percutaneous coronary intervention (PCI). The goal of this study was to evaluate an urban-based PCP STEMI bypass guideline.
We reviewed consecutive Toronto Paramedic Services call reports between April 7, 2015, and May 31, 2016, regarding STEMI patients identified by PCPs. The primary outcome was patient assignment (stable versus unstable) according to guideline criteria. Secondary outcomes were the proportion of PCP-transported patients who had an indication for an advanced care intervention (ACI) or who received an ACI when PCPs rendezvoused with an advanced care paramedic (ACP). Lastly, we reviewed prehospital outcomes of cardiac arrest patients and calculated the difference in transport intervals between direct PCP bypass and a PCI-centre and predicted transport interval to the closest emergency department (ED).
Of 361 patients, 232 were PCP transports and 129 were ACP-rendezvous transports. There was a significant difference in the distribution of stable and unstable patients between PCPs and ACPs (p<0.001). For PCP patients, 21/232 (9.1%) had indications for an ACI, whereas 34/129 (26.4%) ACP patients received an ACI. Eleven patients experienced cardiac arrest; 10 were successfully resuscitated (5 of these by PCPs). The median difference between direct PCP bypass and a PCI-centre versus transport to the closest ED was 5.53 minutes (IQR=6.71).
We found a significant difference in the distribution of stable and unstable patients and fewer patients with indications for an ACI in PCP patients. This PCP STEMI bypass guideline appears feasible.
The Numeniini is a tribe of 13 wader species (Scolopacidae, Charadriiformes) of which seven are Near Threatened or globally threatened, including two Critically Endangered. To help inform conservation management and policy responses, we present the results of an expert assessment of the threats that members of this taxonomic group face across migratory flyways. Most threats are increasing in intensity, particularly in non-breeding areas, where habitat loss resulting from residential and commercial development, aquaculture, mining, transport, disturbance, problematic invasive species, pollution and climate change were regarded as having the greatest detrimental impact. Fewer threats (mining, disturbance, problematic native species and climate change) were identified as widely affecting breeding areas. Numeniini populations face the greatest number of non-breeding threats in the East Asian-Australasian Flyway, especially those associated with coastal reclamation; related threats were also identified across the Central and Atlantic Americas, and East Atlantic flyways. Threats on the breeding grounds were greatest in Central and Atlantic Americas, East Atlantic and West Asian flyways. Three priority actions were associated with monitoring and research: to monitor breeding population trends (which for species breeding in remote areas may best be achieved through surveys at key non-breeding sites), to deploy tracking technologies to identify migratory connectivity, and to monitor land-cover change across breeding and non-breeding areas. Two priority actions were focused on conservation and policy responses: to identify and effectively protect key non-breeding sites across all flyways (particularly in the East Asian- Australasian Flyway), and to implement successful conservation interventions at a sufficient scale across human-dominated landscapes for species’ recovery to be achieved. If implemented urgently, these measures in combination have the potential to alter the current population declines of many Numeniini species and provide a template for the conservation of other groups of threatened species.
Illegal killing/taking of birds is a growing concern across the Mediterranean. However, there are few quantitative data on the species and countries involved. We assessed numbers of individual birds of each species killed/taken illegally in each Mediterranean country per year, using a diverse range of data sources and incorporating expert knowledge. We estimated that 11–36 million individuals per year may be killed/taken illegally in the region, many of them on migration. In each of Cyprus, Egypt, Italy, Lebanon and Syria, more than two million birds may be killed/taken on average each year. For species such as Blackcap Sylvia atricapilla, Common Quail Coturnix coturnix, Eurasian Chaffinch Fringilla coelebs, House Sparrow Passer domesticus and Song Thrush Turdus philomelos, more than one million individuals of each species are estimated to be killed/taken illegally on average every year. Several species of global conservation concern are also reported to be killed/taken illegally in substantial numbers: Eurasian Curlew Numenius arquata, Ferruginous Duck Aythya nyroca and Rock Partridge Alectoris graeca. Birds in the Mediterranean are illegally killed/taken primarily for food, sport and for use as cage-birds or decoys. At the 20 worst locations with the highest reported numbers, 7.9 million individuals may be illegally killed/taken per year, representing 34% of the mean estimated annual regional total number of birds illegally killed/taken for all species combined. Our study highlighted the paucity of data on illegal killing/taking of birds. Monitoring schemes which use systematic sampling protocols are needed to generate increasingly robust data on trends in illegal killing/taking over time and help stakeholders prioritise conservation actions to address this international conservation problem. Large numbers of birds are also hunted legally in the region, but specific totals are generally unavailable. Such data, in combination with improved estimates for illegal killing/taking, are needed for robustly assessing the sustainability of exploitation of birds.
Peer drinking norms are arguably one of the strongest correlates of adolescent drinking. Prospective studies indicate that adolescents tend to select peers based on drinking (peer selection) and their peers' drinking is associated with changes in adolescent drinking over time (peer socialization). The present study investigated whether the peer selection and socialization processes in adolescent drinking differed as a function of the dopamine receptor D4 (DRD4) variable number tandem repeat genotype in two independent prospective data sets. The first sample was 174 high school students drawn from a two-wave 6-month prospective study. The second sample was 237 college students drawn from a three-wave annual prospective study. Multigroup cross-lagged panel analyses of the high school student sample indicated stronger socialization via peer drinking norms among carriers, whereas analyses of the college student sample indicated stronger drinking-based peer selection in the junior year among carriers, compared to noncarriers. Although replication and meta-analytic synthesis are needed, these findings suggest that in part genetically determined peer selection (carriers of the DRD4 seven-repeat allele tend to associate with peers who have more favorable attitudes toward drinking and greater alcohol use) and peer socialization (carriers' subsequent drinking behaviors are more strongly associated with their peer drinking norms) may differ across adolescent developmental stages.
Continuous good-quality deep ice cores provide excellent scientific data with which to reconstruct a past climate record for >800 ka. At depths starting from ∼100m using an electromechanical drill, a drilling liquid is essential for successful recovery of the very high-quality ice cores demanded by modern scientific analysis techniques (e.g. continuous flow analysis). Finding a suitable drill fluid for use at deep ice-coring drill sites is not an easy task. Temperatures vary greatly not just from site to site, but also at a site where the average mean temperature from surface to bedrock can vary from –55°C to –2.75°C. In the past 60 years, many fluids have been used, with varying degrees of success, but for various reasons are either unavailable, are now considered unsafe and dangerous or are too environmentally damaging to be permitted. Here we report on our pre-season investigation into possible candidate drill fluids, with specific information concerning ESTISOL™ 240 and COASOL™, the rationale behind the redesign of our drill successfully used at NorthGRIP, Greenland, and EPICA DML, Antarctica, the knock-on effect of those changes, and our field experience in Greenland at Flade Isblink in 2006 and at NEEM in 2009–10.
This study investigates Sr surface segregation behavior and phase formation in La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF), a commonly used cathode material for solid oxide fuel cells (SOFCs). (100)-oriented LSCF thin films were deposited on (110)-oriented NdGaO3 (NGO) substrates by Pulsed Laser Deposition (PLD). The samples were annealed in atmospheres with various CO2 partial pressures at 800°C. Using the synchrotron technique of Total Reflection X-ray Fluorescence (TXRF), surface segregation in these thin films were quantified. The morphological changes at the surface were examined by AFM studies. The kinetics and thermodynamics of the segregation are discussed.
In this paper we report the properties of the anodic silicon dioxide film formed using light-induced anodisation (LIA) method and its potential to be used as surface passivation layer of p-type silicon surfaces of silicon solar cells. The high uniformity of the formed oxide is possibly due to the uniform drift of the positive charge carriers in the silicon to the surface being anodised. The oxide grows at higher rate than that in nitric acid, an oxide layer with thickness of 18 nm can be formed by anodising for 10 min with 15 V bias in 0.5 M sulphuric acid. After annealing in oxygen and then forming gas at 400 °C for 30 min, an average effective carrier lifetime of 120 μs was measured by quasi-steady state photoluminance on 180 μm p-type 3-5 Ohm cm Cz silicon wafers, with a value of 110 μs being measured for the same wafers passivated by a thermally-grown oxide of the same thickness. The properties of the anodic silicon dioxide layers formed by LIA have been characterized by ellipsometry, x-ray photoelectron spectroscopy, quasi-steady state photoluminance and Fourier transform infrared spectroscopy.
The surface passivation of Si wafer by AlOx thin films grown by mist CVD in an open-air atmosphere was studied with a view to improving the effect of high-performance c-Si solar cells. In AlOx thin film grown at a temperature above 400°C by mist CVD, the OH bonding did not remain in the film and the breakdown field (EBD) was over 6 MV/cm. In Si wafers passivated by AlOx thin films grown by mist CVD at growth temperature above 400°C, the negative fixed charge density (Qf) at the interface was higher than 1012 cm-2 and the surface recombination velocity (Seff) was 44.4 cm/s. These results show that mist CVD, which is fundamentally an environmentally friendly technique, may be suitable for the fabrication of a passivation film on Si surfaces designed to improve the effect of high-performance c-Si solar cells.
The n-type GaN has stability problem of the surface anodic corrosion during the photoelectrochemical reaction for H2 generation. The photoelectrochemical surface stabilities of n-type GaN dependent on the electrolytes were investigated. The flatband potential in HCl obtained from Mott-Schottky plot shifted 0.1 V to positive direction compared with that in H2SO4. The variation of saturated photocurrent of 1 to 3 cycles in H2SO4 was much larger than that of HCl, NaOH and KOH. The surface morphologies also changed by the electrolytes. These results show the absorbed materials on the GaN electrode surface during the photoelectrochemical reactions were changed by the electrolyte and affected the surface reactions.
A drill liquid is essential for the purpose of recovering good-quality scientifically useful ice cores at intermediate to deep depths, i.e. >∼100 m. The pressure produced by the liquid helps to eliminate the detrimental effects of the abrupt release of isostatic pressure in the ice during the drilling process, prevents consequential fractures within the ice core, and is essential to produce an even distribution of hydrostatic pressure to balance the ice isostatic pressure and so minimize borehole deformation. To perform these tasks, while minimizing risks to health and the environment, the liquid needs to exhibit specific physical, chemical and biological characteristics. Here we report on two promising candidate drill liquids, ESTISOL™ 140 and ESTISOL™ 165, for use in the extreme conditions found within the ice sheets of Greenland and Antarctica, where the temperature can range from close to 0°C to below −57°C and pressures can exceed 40 MPa. From both the manufacturer’s data and our laboratory tests and observations we report on the physical, chemical and biological characteristics that both liquids exhibit. We also report on how one of the candidates was field-tested on the Greenland ice sheet and the East Antarctic high plateau.
Surface-induced aromatic stabilization (SIAS), a recently proposed mechanism leading to a formation of charge-transfer (CT) states at organic/metal (O/M) interfaces [G. Heimel, et al., Nat. Chem.5, 187 (2013)], was investigated for an aromatic hydrocarbon, diindenoperylene (DIP), by means of synchrotron radiation-based ultraviolet photoelectron spectroscopy (UPS). By employing DIP and noble metal substrates (Ag and Cu), we confirmed the formation of CT states, indicating that an inclusion of a specific functional group with a hetero-atom within adsorbate molecules as suggested before is not necessarily required for the formation of CT states mediated by the SIAS. With a comparison of the mother and analogue molecules, perylene and PTCDA, we discuss the structural requirement for the realization of the SIAS.
Increasing interest in the photocatalytic activity of TiO2 has led to considerations of using TiO2 nanoparticles in energy generation. In order to better understand the electron-hole relaxation of nano scale TiO2 structures, it is important to start with an understanding of TiO2 synthesis building blocks. The solvated titanium (IV) ion is a precursor found in synthesis methods of colloidal TiO2 nanostructures. This simplest test compound may reflect some common basic electronic features for larger structures composed of Ti(IV) coordinated with oxygen. For this computational study, a model of Ti(OH)4 with tetrahedral coordination was created. To simulate the electronic properties of a solution of Ti(IV), the model was surrounded with 27 H2O molecules. The model was explored by means of standard density functional theory (DFT) molecular dynamics (MD) followed by nonadiabatic electron dynamics computed with Reduced Density Matrix approach combined with “on-the-fly coupling”. Results were generated with Vienna ab initio Simulation Package (VASP) using the Perdew-Burke-Ernzerhof (PBE) functional, plane wave basis set, and projector augmented wave (PAW) potentials. The absorption spectra, MD, and electron-hole relaxation rates are presented for the Ti(OH)4 model at various ambient temperatures. The electron-hole relaxation rates show a non-linear dependence on temperature and were found to be near the same order of magnitude as electron-hole relaxation rates in bulk TiO2 calculations. A video of the geometry optimization can be found online.
The purpose of this investigation was to test the hypothesis that maternal exercise training during pregnancy enhances endothelial function in offspring at birth. Six-month-old gilts (n = 8) were artificially inseminated and randomized into exercise-trained (n = 4) and sedentary groups (n = 4). Exercise training consisted of 15 weeks of treadmill exercise. The thoracic aorta of offspring were harvested within 48 h after birth and vascular responsiveness to cumulative doses of endothelium-dependent (bradykinin: 10−11–10−6 M) and independent (sodium nitroprusside: 10−10–10−4 M) vasodilators were assessed using in vitro wire myography. Female offspring from the exercised-trained gilts had a significantly greater endothelium-dependent relaxation response in the thoracic aorta when compared with the male offspring and female offspring from the sedentary gilts. The results of this investigation demonstrate for the first time that maternal exercise during pregnancy produces an enhanced endothelium-dependent vasorelaxation response in the thoracic aortas of female offspring at birth.
In Mozambique and Cape Verde, writing in Portuguese by African women has directly engaged political reconstruction by denouncing colonial oppression and embracing national freedom. This article addresses the recent history of Lusophone African women's fiction, which has been pivotal in inscribing the intimate arena of sexuality and motherhood into power relations and has also revealed ways in which the domain of violence intersects with private lives. By focusing on two novels that exemplify this trend, this article demonstrates links between the political and the intimate. It also shows how Lusophone African authors contribute to healing social conflict through their narratives, and draws some conclusions about gender relations in the Lusophone African experience and across the continent.