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This list of radiocarbon age measurements is for the period 1972–1974. Most of the samples are of archaeologic interest. The pretreatments of samples used are basically those described by Ralph and Michael (1971). All samples were converted to methane using the method developed by Fairhall, Schell, and Takashima (1961) and counted in .5L counting tubes at 2 to 4atm of pressure. The WSU Radiocarbon Laboratory has been relocated to the basement of Dana Hall (three stories) and additional shielding has been added. The backgrounds of the counting tubes are .90 counts/min and have an atmospheric pressure dependence of –.035 counts/min/cm Hg.
Obtaining intravenous (IV) access in patients in hemorrhagic shock is often difficult and prolonged. Failed IV attempts delay life-saving treatment. Intraosseous (IO) access may often be obtained faster than IV access. Albumin (5%) is an option for prehospital volume expansion because of the absence of interference with coagulation and platelet function.
There are limited data comparing the performance of IO and IV administered 5% albumin. The aims of this study were to compare the effects of tibial IO (TIO) and IV administration of 500 mL of 5% albumin on infusion time and hemodynamic measurements of heart rate (HR), mean arterial pressure (MAP), cardiac output (CO), and stroke volume (SV) in a swine model of hemorrhagic shock.
Sixteen male swine were divided into two groups: TIO and IV. All subjects were anesthetized and a Class III hemorrhage was achieved by exsanguination of 31% of estimated blood volume (EBV) from a femoral artery catheter. Following exsanguination, 500 mL of 5% albumin was administered under pressurized infusion (300 mmHg) by the TIO or IV route and infusion time was recorded. Hemodynamic measurements of HR, MAP, CO, and SV were collected before and after exsanguination and every 20 seconds for 180 seconds during 5% albumin infusion.
An independent t-test determined that IV 5% albumin infusion was significantly faster compared to IO (P=.01). Mean infusion time for TIO was seven minutes 35 seconds (SD=two minutes 44 seconds) compared to four minutes 32 seconds (SD=one minute 08 seconds) in the IV group. Multivariate Analysis of Variance was performed on hemodynamic data collected during the 5% albumin infusion. Analyses indicated there were no significant differences between the TIO and IV groups relative to MAP, CO, HR, or SV (P>.05).
While significantly longer to infuse 5% albumin by the TIO route, the longer TIO infusion time may be negated as IO devices can be placed more quickly compared to repeated IV attempts. The lack of significant difference between the TIO and IV routes relative to hemodynamic measures indicate the TIO route is a viable route for the infusion of 5% albumin in a swine model of Class III hemorrhage.
MuirSL, SheppardLB, Maika-WilsonA, BurgertJM, Garcia-BlancoJ, JohnsonAD, CoynerJL. A Comparison of the Effects of Intraosseous and Intravenous 5% Albumin on Infusion Time and Hemodynamic Measures in a Swine Model of Hemorrhagic Shock. Prehosp Disaster Med.2016;31(4):436–442.
The Parkes multibeam pulsar survey which began in 1997 and is now about 50% complete. It has discovered more than 400 new pulsars so far, including a number of young, high magnetic field, and relativistic binary pulsars. Early results, descriptions of the survey and follow up timing programs can be found in papers by Lyne et al. (1999 MNRAS in press), Camilo et al. (this volume), and Manchester et al. (this volume). This paper describes the data release policy and how you can gain access to the raw data and details on the pulsars discovered.
The Parkes multibeam pulsar survey uses a 13-element receiver operating at a wavelength of 20 cm to survey the inner Galactic plane with remarkable sensitivity. To date we have collected and analyzed data from 45% of the survey region (|b| < 5°; 260° < l < 50°), and have discovered 440 pulsars, in addition to re-detecting 190 previously known ones. Most of the newly discovered pulsars are at great distances, as inferred from a median dispersion measure (DM) of 400 cm−3 pc.
There is an opportunity for scaling up, optimizing, and controlling the process of production of nanoparticles due to their numerous diverse applications. We present a system for continuous, high rate production of nanoparticles, particularly those of carbon, using large volume thermal plasma based on a three-phase diverging electrode configuration. The goal of using this 3-phase plasma reactor is to have a plasma arc that is scalable, self-stabilizing, and low maintenance, with sufficient plasma volume to maximize residence time of feed materials for evaporation to atomic species. Plasma carrier gas, typically inert gas such as helium, is injected into the reactor allowing the vaporization of any feedstock due to plasma temperatures >5000 °C. Controlling plasma enthalpy, diffusion/temperature gradients and carbon feed rates allow the controlled growth of clusters leading to nanoparticles less than 100 nm. Once the desired size is achieved the gas stream is expanded to reduce the reaction rate and quenched by natural cooling to chamber walls or injection of a cooling gas stream, preferably of the same composition as plasma carrier gas. Recoverable yields in the nanoparticle-laden gas stream are then isolated by standard means (filtration, cyclone separation, electrostatic precipitation), and the plasma gas and unreacted feedstock are routed to the plasma reactor for recycling. Computational Fluid Dynamics (CFD) is employed to measure and predict fluid flow, energy/temperature, and other species distributions in the plasma process.
Carbon nanotubes come in many varieties, with chemical, mechanical, and electrical properties depending on carbon nanotube (CNT) structural morphology. In order to provide a platform for CNT structural tuning, a membrane reactor was designed and constructed. This reactor provided more intimate gas-catalyst contact by decoupling the carbon feedstock gas from carrier gas in a chemical vapour deposition (CVD) environment using an asymmetric membrane and a macroporous membrane. Growth using this membrane reactor demonstrated normalized yield improvements of ∼300% and ∼1000% for the asymmetric and macroporous membrane cases, respectively, over standard CVD methods. To illustrate the possibility for control, growth variation with time was successfully demonstrated by growing vertically aligned multi-walled CNTs to heights of 0.71 mm, 1.36 mm, and 1.84 mm after growth for 15, 30, and 60 minutes in a commercial thermal CVD reactor. To demonstrate CNT diameter control via catalyst particle size, dip coating and spray coating methods were explored using ferrofluid and Fe(NO3)3 systems. CNT diameter was demonstrated to increase with increasing particle size, yielding CNT like growth with diameters ranging from 15 -150 nm. Demonstration of these dimensions of control coupled with the dramatic efficiency increases over growth in a commercialized CVD reactor establish this new reactor technology as a starting point for further research into CNT structural tuning.
Growth and propagation of fish-infecting microsporidians within cell culture has been more difficult to achieve than for insect- and human-infecting microsporidians. Fish microsporidia tend to elicit xenoma development rather than diffuse growth in vivo, and this process likely increases host specificity. We present evidence that the fish microsporidian, Loma salmonae, has the capacity to develop xenomas within a rainbow trout gill epithelial cell line (RTG-1). Spore numbers increased over a 4 weeks period within cell culture flasks. Xenoma-like structures were observed using phase contrast microscopy, and then confirmed using transmission electron microscopy. Optimization of the L. salmonae-RTG-1 cell model has important implications in elucidating the process of xenoma development induced by microsporidian parasites.
The principles embodied by the Developmental Origins of Health and Disease (DOHaD) view of ‘life history’ trajectory are increasingly underpinned by biological data arising from molecular-based epigenomic and transcriptomic studies. Although a number of ‘omic’ platforms are now routinely and widely used in biology and medicine, data generation is frequently confounded by a frequency distribution in the measurement error (an inherent feature of the chemistry and physics of the measurement process), which adversely affect the accuracy of estimation and thus, the inference of relationships to other biological measures such as phenotype. Based on empirical derived data, we have previously derived a probability density function to capture such errors and thus improve the confidence of estimation and inference based on such data. Here we use published open source data sets to calculate parameter values relevant to the most widely used epigenomic and transcriptomic technologies Then by using our own data sets, we illustrate the benefits of this approach by specific application, to measurement of DNA methylation in this instance, in cases where levels of methylation at specific genomic sites represents either (1) a response variable or (2) an independent variable. Further, we extend this formulation to consideration of the ‘bivariate’ case, in which the co-dependency of methylation levels at two distinct genomic sites is tested for biological significance. These tools not only allow greater accuracy of measurement and improved confidence of functional inference, but in the case of epigenomic data at least, also reveal otherwise cryptic information.
In August 2012, an explosive outbreak of severe lower respiratory tract infection (LRTI) due to Streptococcus pneumoniae serotype-8 occurred in a highly vaccinated elderly institutionalized population in England. Fifteen of 23 residents developed LRTI over 4 days (attack rate 65%); 11 had confirmed S. pneumoniae serotype-8 disease, and two died. Following amoxicillin chemoprophylaxis and pneumococcal polysaccharide vaccine (PPV) re-vaccination no further cases occurred in the following 2 months. No association was found between being an outbreak-associated case and age (P = 0·36), underlying comorbidities [relative risk (RR) 0·84 95% confidence interval (CI) 0·34–2·09], or prior receipt of PPV (RR 1·4, 95% CI 0·60–3·33). However, the median number of years since PPV was significantly higher for cases (n = 15, 10·2 years, range 7·3–17·9 years) than non-cases (n = 8, 7·2 years, range 6·8–12·8 years) (P = 0·045), provided evidence of waning immunity. Alternative vaccination strategies should be considered to prevent future S. pneumoniae outbreaks in institutionalized elderly populations.
Human campylobacteriosis exhibits a distinctive seasonality in temperate regions. This paper aims to identify the origins of this seasonality. Clinical isolates [typed by multi-locus sequence typing (MLST)] and epidemiological data were collected from Scotland. Young rural children were found to have an increased burden of disease in the late spring due to strains of non-chicken origin (e.g. ruminant and wild bird strains from environmental sources). In contrast the adult population had an extended summer peak associated with chicken strains. Travel abroad and UK mainland travel were associated with up to 17% and 18% of cases, respectively. International strains were associated with chicken, had a higher diversity than indigenous strains and a different spectrum of MLST types representative of these countries. Integrating empirical epidemiology and molecular subtyping can successfully elucidate the seasonal components of human campylobacteriosis. The findings will enable public health officials to focus strategies to reduce the disease burden.
This trial aimed to compare the guillotine technique of tonsillectomy with ‘cold steel’ dissection, the current ‘gold standard’.
A single centre, randomised, controlled trial.
One hundred children aged 3 to 11 years who were listed for bilateral tonsillectomy were recruited. Patients had one tonsil removed by each technique, and were blinded to the side. The operative time, intra-operative blood loss, haemostasis requirement and post-operative pain scores were recorded and compared.
Operative time and intra-operative blood loss were both significantly less for the guillotine technique (p < 0.001) and there was a significantly reduced haemostasis requirement (p < 0.001). Pain was also less on the guillotine side (p < 0.001). There were no tonsillar remnants or palatal trauma for either technique. There was no significant difference between techniques in the frequency of secondary haemorrhage.
This study provides level Ib evidence that guillotine tonsillectomy in children with mobile tonsils is an effective and time-efficient procedure which produces less intra-operative blood loss and post-operative pain than cold steel dissection.
Blastomycosis is a systemic fungal infection found in various parts of the world. A review of literature for Quebec, Canada revealed only few case reports with the most recent one dating back to 1993. However, whether Quebec represents an important endemic region for blastomycosis in North America is unknown. In this work we reviewed 158 cases of human blastomycosis documented in Quebec during 1988–2011 using microbiological records available from the provincial public health laboratory. The estimated annual incidence of blastomycosis in the province is was ∼0·133 cases per 100 000 individuals with the highest rates of 0·79 and 0·46 cases per 100 000 recorded in South-eastern and South-western Quebec. Moreover, the annual incidence rate significantly increased over the past 20 years. This study for the first time establishes Quebec as an important endemic region for Blastomyces dermatitidis.
Factors resulting in high risk for cardiovascular disease have been well studied in high income countries, but have been less well researched in low/middle income countries. This is despite robust theoretical evidence of environmental transitions in such countries which could result in biological adaptations that lead to increased hypertension and cardiovascular disease risk. Data from the South African Birth to Twenty cohort, Bone Health sub-sample (n=358, 47% female), were used to model associations between household socioeconomic status (SES) in infancy, household/neighbourhood SES at age 16 years, and systolic blood pressure (multivariate linear regression) and risk for systolic pre-hypertension (binary logistic regression). Bivariate analyses revealed household/neighbourhood SES measures that were significantly associated with increased systolic blood pressure. These significant associations included improved household sanitation in infancy/16 years, caregiver owning the house in infancy and being in a higher tertile (higher SES) of indices measuring school problems/environment or neighbourhood services/problems/crime at 16 years of age. Multivariate analyses adjusted for sex, maternal age, birth weight, parity, smoking, term birth, height/body mass index at 16 years. In adjusted analyses, only one SES variable remained significant for females: those in the middle tertile of the crime prevention index had higher systolic blood pressure (β=3.52, SE=1.61) compared with the highest tertile (i.e. those with the highest crime prevention). In adjusted analyses, no SES variables were significantly associated with the systolic blood pressure of boys, or with the risk of systolic pre-hypertension in either sex. The lack of association between SES and systolic blood pressure/systolic pre-hypertension at age 16 years is consistent with other studies showing an equalization of adolescent health inequalities. Further testing of the association between SES and systolic blood pressure would be recommended in adulthood to see whether the lack of association persists.
SiC MESFET's have shown an RF power density of 4.6 W/mm at 3.5 GHz and a power added efficiency of 60% with 3 W/mm at 800 MHz, demonstrating that SiC devices are capable of very high power densities and high efficiencies. Single devices with 48 mm of gate periphery were mounted in a hybrid circuit and achieved a maximum RF power of 80 watts CW at 3.1 GHz with 38% PAE.
Thin films of electroconductive poly[pyrrole-co-3−(1−pyrrolyl)propionic acid] were prepared by electropolymerization onto 3-aminopropyltrimethoxysilane modified and 3−(1−pyrrolyl)propionic acid derivatized interdigitated microsensor electrode (IME) arrays. The ω−(1−pyrrolyl) moiety on the surface of the device provides for specific adhesion of the polymer film to the device and the (N-pyrrolyl)propionic acid moiety on the polymer backbone provides for covalent attachment of bioactive molecules, such as biotin and urease, to the polymer surface. The immobilized, bioactive urease produces an ON/OFF conductimetric response traceable to analyte concentration.
Single crystal thin films with compositions from the A1N-InN-GaN system were grown via metal-organic chemical vapor deposition (MOCVD) on single crystal 6H-SiC substrates. Blue light emitting (LED) and laser diode (LD) structures were fabricated. The conducting buffer layer LEDs employed an AlGaN buffer layer which provides a conduction path between SiC and the active device region. The external quantum efficiency of the LEDs was 3% at 20 mA- 3.6V and peak emission wavelength of 430 nm. Violet and blue LDs were fabricated and consisted of an 8-well InGaN/GaN multiple quantum well (MQW) active region in a separate confinement heterostructure (SCH) design. Lasing was obtained both on structures using an insulating buffer layer, and also on structures using a conducting buffer layer. The resulting lasers operated at room temperature using pulsed and continuous wave operation with an emission wavelength of 404-435 rim. The lowest threshold current density obtained for lasing was 11 kA/cm2.
This paper reports the events at NCSU leading up to and including those of June 5, 1997 which produced the first demonstration of a nitride laser diode on silicon carbide – and the very first nitride laser demonstration outside of Japan. All of the laser diode samples tested at NCSU were designed, grown, and fabricated into cleaved cavity test structures at Cree Research. Laser testing at NCSU consisted of spectral emission versus current measurements, light output power versus current (L-I) measurement, and light output polarization measurements versus current. The first successful laser on silicon carbide emitted at 402.6 nm. Subsequently, lasers displaying outputs ranging from 402.6 to 430.2 have been successfully tested at NCSU.