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Each of the laboratory intercomparisons (from ICS onwards) has included wood samples, many of them dendrochronologically dated. In the early years, as a result of the majority of laboratories being radiometric, these samples were typically blocks of 20–40 rings, but more recently (SIRI), they have been single ring samples. The sample ages have spanned background through to modern. In some intercomparisons, we have examined different wood pretreatment effects, in others the focus has been on background samples. In this paper, we illustrate what we have learned from these extensive intercomparisons involving wood samples and how the results contribute to the global IntCal effort.
Excitable temperament disrupts physiological events required for reproductive development in cattle, but no research has investigated the impacts of temperament on growth and puberty attainment in Bos indicus females. Hence, this experiment evaluated the effects of temperament on growth, plasma cortisol concentrations and puberty attainment in B. indicus heifers. A total of 170 Nelore heifers, weaned 4 months before the beginning of this experiment (days 0 to 91), were managed in two groups of 82 and 88 heifers each (mean ± SE; initial BW=238±2 kg, initial age=369±1 days across groups). Heifer temperament was evaluated via exit velocity on day 0. Individual exit score was calculated within each group by dividing exit velocity into quintiles and assigning heifers with a score from 1 to 5 (1=slowest; 5=fastest heifer). Heifers were classified according to exit score as adequate (ADQ, n=96; exit score⩽3) or excitable temperament (EXC, n=74; exit score>3). Heifer BW, body condition score (BCS) and blood samples were obtained on days 0, 31, 60 and 91. Heifer exit velocity and score were recorded again on days 31, 60 and 91. Ovarian transrectal ultrasonography was performed on days 0 and 10, 31 and 41, 60 and 70, 81 and 91 for puberty evaluation. Heifer was declared pubertal at the first 10-day interval in which a corpus luteum was detected. Exit velocity and exit score obtained on day 0 were correlated (r⩾0.64, P<0.01) with evaluations on days 31, 60 and 91. During the experiment, ADQ had greater (P<0.01) mean BCS and BW gain, and less (P<0.01) mean plasma cortisol concentration compared with EXC heifers. Temperament × time interactions were detected (P<0.01) for exit velocity and exit score, which were always greater (P<0.01) in EXC v. ADQ heifers. A temperament × time interaction was also detected (P=0.03) for puberty attainment, which was delayed in EXC v. ADQ heifers. At the end of the experiment, a greater (P<0.01) proportion of ADQ were pubertal compared with EXC heifers. In summary, B. indicus heifers classified as EXC had reduced growth, increased plasma cortisol concentrations and hindered puberty attainment compared to ADQ heifers. Moreover, exit velocity may serve as temperament selection criteria to optimize development of B. indicus replacement heifers.
Antibodies at gastrointestinal mucosal membranes play a vital role in immunological protection against a range of pathogens, including helminths. Gastrointestinal health is central to efficient livestock production, and such infections cause significant losses. Fecal samples were taken from 114 cattle, across three beef farms, with matched blood samples taken from 22 of those animals. To achieve fecal antibody detection, a novel fecal supernatant was extracted. Fecal supernatant and serum samples were then analysed, using adapted enzyme-linked immunosorbent assay protocols, for levels of total immunoglobulin (Ig)A, IgG, IgM, and Teladorsagia circumcincta-specific IgA, IgG, IgM and IgE (in the absence of reagents for cattle-specific nematode species). Fecal nematode egg counts were conducted on all fecal samples. Assays performed successfully and showed that IgA was the predominant antibody in fecal samples, whereas IgG was predominant in serum. Total IgA in feces and serum correlated within individuals (0.581, P = 0.005), but other Ig types did not. Results support the hypothesis that the tested protocols are an effective method for the non-invasive assessment of cattle immunology. The method could be used as part of animal health assessments, although further work is required to interpret the relationship between results and levels of infection and immunity.
The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
The Nevado de Toluca is a stratovolcano located in the southwest of the Toluca Valley in central Mexico. At a height of around 4200 m there are two crater lakes: El Sol and La Luna. Since Precolumbian times, people in the surrounding valleys carried out rituals and deposited offerings into the lakes. After the Spanish conquest, these rituals were kept alive clandestinely. Currently, reminiscent of Mesoamerican rituals subsist. Due to the long duration of the ritual at the Nevado de Toluca, it is important to date the materials recovered in the underwater and terrestrial archaeological explorations. This article proposes a chronology of Prehispanic ritual activities performed in the Nevado de Toluca based on the characterization and radiocarbon (14C) dating performed to materials from the volcano’s lakes.
Identifying genetic relationships between complex traits in emerging adulthood can provide useful etiological insights into risk for psychopathology. College-age individuals are under-represented in genomic analyses thus far, and the majority of work has focused on the clinical disorder or cognitive abilities rather than normal-range behavioral outcomes.
This study examined a sample of emerging adults 18–22 years of age (N = 5947) to construct an atlas of polygenic risk for 33 traits predicting relevant phenotypic outcomes. Twenty-eight hypotheses were tested based on the previous literature on samples of European ancestry, and the availability of rich assessment data allowed for polygenic predictions across 55 psychological and medical phenotypes.
Polygenic risk for schizophrenia (SZ) in emerging adults predicted anxiety, depression, nicotine use, trauma, and family history of psychological disorders. Polygenic risk for neuroticism predicted anxiety, depression, phobia, panic, neuroticism, and was correlated with polygenic risk for cardiovascular disease.
These results demonstrate the extensive impact of genetic risk for SZ, neuroticism, and major depression on a range of health outcomes in early adulthood. Minimal cross-ancestry replication of these phenomic patterns of polygenic influence underscores the need for more genome-wide association studies of non-European populations.
The contribution to sea level to 2200 from the grounded, mainland Antarctic Peninsula ice sheet (APIS) was calculated using an ice-sheet model initialized with a new technique computing ice fluxes based on observed surface velocities, altimetry and surface mass balance, and computing volume response using a linearized method. Volume change estimates of the APIS resulting from surface mass-balance anomalies calculated by the regional model RACMO2, forced by A1B and E1 scenarios of the global models ECHAM5 and HadCM3, predicted net negative sea-level contributions between −0.5 and −12 mm sea-level equivalent (SLE) by 2200. Increased glacier flow due to ice thickening returned ∼15% of the increased accumulation to the sea by 2100 and ∼30% by 2200. The likely change in volume of the APIS by 2200 in response to imposed 10 and 20 km retreats of the grounding line at individual large outlet glaciers in Palmer Land, southern Antarctic Peninsula, ranged between 0.5 and 3.5 mm SLE per drainage basin. Ensemble calculations of APIS volume change resulting from imposed grounding-line retreat due to ice-shelf break-up scenarios applied to all 20 of the largest drainage basins in Palmer Land (covering ∼40% of the total area of APIS) resulted in net sea-level contributions of 7–16 mm SLE by 2100, and 10–25 mm SLE by 2200. Inclusion of basins in the northern peninsula and realistic simulation of grounding-line movement for AP outlet glaciers will improve future projections.
Dementia is a neurodegenerative syndrome that interferes with multiple aspects of life, including cognition, daily functioning, and behavior. Despite the large heterogeneity in symptom development, these three domains are seldom studied simultaneously. This study investigates how trajectories of these domains are interrelated within individuals over time, and how they in turn are related to dementia severity and quality of life (QoL).
We used data from a longitudinal clinical cohort study, including 331 dementia patients. Cognitive status was measured using the Mini-Mental State Examination, daily functioning was measured with the disability assessment for dementia and neuropsychiatric symptoms (NPS) were scored using the neuropsychiatric inventory. We investigated the relationships in the time course of the various dementia domains using random effects multilevel models and parallel-process growth models.
Changes in cognition and daily functioning were highly correlated over time (r = 0.85, p < 0.01), as were changes in NPS and functioning (r = −0.60, p < 0.01), while changes in cognition and NPS were not (r = −0.20, p = 0.06). All three domains were strongly associated with dementia severity over time (p < 0.01). Decreased functioning and increased NPS were both associated with decreased QoL (β = 2.97, p < 0.01 and β = −2.41, p < 0.01, respectively), while cognition was not (β = 0.01, p = 0.93).
This study demonstrates the heterogeneity of dementia progression between individuals and between different dementia domains within individuals. To improve our understanding of dementia progression, future research should embrace a broader perspective encompassing multiple outcome measures along with the patient's profile, including neurological factors as well as physical, social, and psychiatric health.
The Caltech imaging γ-ray telescope was launched by balloon from Alice Springs, NT, Australia and performed observations of the galactic center during the period 12.62 to 13.00 April 1988 UT. The first coded-aperture images of the galactic center region at energies above 30 keV show a single strong γ-ray source which is located 0.7±0.1° from the galactic nucleus and is tentatively identified as 1E1740.7-2942. If the source is at the distance of the galactic center, it is one of the most luminous objects in the galaxy at energies from 35 to 200 keV.
A previous radiocarbon dating and stable isotope study of directly associated ungulate and human bone samples from Late Mesolithic burials at Schela Cladovei in Romania established that there is a freshwater reservoir effect of approximately 500 yr in the Iron Gates reach of the Danube River valley in southeast Europe. Using the δ15N values as an indicator of the percentage of freshwater protein in the human diet, the 14C data for 24 skeletons from the site of Lepenski Vir were corrected for this reservoir effect. The results of the paired 14C and stable isotope measurements provide evidence of substantial dietary change over the period from about 9000 BP to about 300 BP. The data from the Early Mesolithic to the Chalcolithic are consistent with a 2-component dietary system, where the linear plot of isotopic values reflects mixing between the 2 end-members to differing degrees. Typically, the individuals of Mesolithic age have much heavier δ15N signals and slightly heavier δ13C, while individuals of Early Neolithic and Chalcolithic age have lighter δ15N and δ13C values. Contrary to our earlier suggestion, there is no evidence of a substantial population that had a transitional diet midway between those that were characteristic of the Mesolithic and Neolithic. However, several individuals with “Final Mesolithic” 14C ages show δ15N and δ13C values that are similar to the Neolithic dietary pattern. Provisionally, these are interpreted either as incomers who originated in early farming communities outside the Iron Gates region or as indigenous individuals representing the earliest Neolithic of the Iron Gates. The results from Roman and Medieval age burials show a deviation from the linear function, suggesting the presence of a new major dietary component containing isotopically heavier carbon. This is interpreted as a consequence of the introduction of millet into the human food chain.
Human bones from single inhumation burials and artifacts made from terrestrial mammal (ungulate) bone found in direct association with the skeletons were obtained from the Stone Age site of Schela Cladovei situated just below the Iron Gates Gorge of the River Danube. The results of stable isotope analyses of the human bone collagen are consistent with a heavy dependence on aquatic protein while radiocarbon dating of the samples reveals an offset of 300–500 years between the two sample types, indicating a freshwater reservoir effect in the human bone samples. Since protein consumption is by far the major source of nitrogen in the human diet we have assumed a linear relationship between δ15N and the level of aquatic protein in each individual's diet and derived a calibration for 14C age offset versus δ15N which has been applied to a series of results from the site at Lepenski Vir within the gorge. The corrected 14C ages (7310-6720 BP) are now consistent with the previous 14C age measurements made on charcoal from related contexts (7360–6560 BP). In addition, the data indicate a change from a primarily aquatic to a mixed terrestrial/aquatic diet around 7100 BP and this may be argued as supporting a shift from Mesolithic to Neolithic. This study also has wider implications for the accurate dating of human bone samples when the possibility exists of an aquatic component in the dietary protein and strongly implies that δ15N analysis should be undertaken routinely when dating human bones.
In 2003, a National Electrostatics Corporation (NEC) 5MV tandem accelerator mass spectrometer was installed at SUERC, providing the radiocarbon laboratory with 14C measurements to 4–5‰ repeatability. In 2007, a 250kV single-stage accelerator mass spectrometer (SSAMS) was added to provide additional 14C capability and is now the preferred system for 14C analysis. Changes to the technology and to our operations are evident in our copious quality assurance data: typically, we now use the 134-position MC-SNICS source, which is filled to capacity. Measurement of standards shows that spectrometer running without the complication of on-line δ13C evaluation is a good operational compromise. Currently, 3‰ 14C/13C measurements are routinely achieved for samples up to nearly 3 half-lives old by consistent sample preparation and an automated data acquisition algorithm with sample random access for measurement repeats. Background and known-age standard data are presented for the period 2003–2008 for the 5MV system and 2007–2008 for the SSAMS, to demonstrate the improvements in data quality.
A new National Electrostatic Corporation (NEC) 5MV accelerator mass spectrometer became operational at the Scottish Universities Environmental Research Centre (SUERC) in July 2002. It has 2 Cs sputter negative ion sources: a 134-sample source (S1) for the routine measurement of all species, and a hybrid source (S2) with 40 spaces for radiocarbon measurements with either graphite or CO2 samples. A number of performance tests on graphite samples have been carried out on both sources. A precison of better than 0.3% is feasible for modern samples on a routine basis. The 14C background of the machine and the graphite preparation process blank are 0.04 ± 0.01 and 0.16 ± 0.05 pMC, respectively, indicating that 14C dating back to ~50 kyr BP is possible. The normalized 14C values for a series of reference materials agree well with the IAEA, TIRI, and FIRI consensus values. Routine measurement of 14C has been underway since May 2003. Preliminary results of performance tests on the CO2 gas ion source are also reported.
Introduction: Nova Scotia has a province wide reperfusion strategy for the treatment of patients presenting with acute ST-Elevation Myocardial Infarction (STEMI). Patients are referred for primary percutaneous coronary intervention (PPCI) if a first medical contact to device time can be achieved within 90 to 120 minutes; otherwise, fibrinolytic therapy is administered, as per guideline recommendations. Since 2011, Nova Scotian paramedics have been providing prehospital fibrinolysis (PHF) and prehospital catheterization (cath) lab activation for STEMI patients outside and within the PPCI catchment area, respectively. Patients who received fibrinolysis are transferred to a PCI facility if rescue PCI is required or if there are other indications for urgent intervention. This province wide approach is unique and the objective of this retrospective cohort study is to compare the impact of this approach on the primary outcome of 30-day mortality. Methods: For the study period, July 2011 to July 2013, STEMI patients who were diagnosed prehospital or in the ED who subsequently underwent reperfusion therapy were identified in the Emergency Health Services (EHS), Cardiovascular Information Systems (CVIS) and Cardiovascular Health Nova Scotia (CVHNS) databases. Baseline demographics and outcomes were then compared according to the treatment received: 1) PHF; 2) ED Fibrinolysis (EDF); 3) prehospital activated PPCI (EHS PPCI); and 4) ED activated PPCI (ED PPCI). Results: There were a total of 1107 STEMI patients identified during the study period, of whom 742 received lytic therapy (146 PHF; 596 EDF) and 332 underwent PPCI (202 EHS PPCI; 130 ED PPCI). Demographic variables were similar across the groups. The primary outcome of 30-day mortality was not significantly different across groups: 5 (3%) in PHF, 26 (4%) in EDF, 8 (4%) in EHS to PPCI and 2 (2%) in ED to PPCI. The number of rescue PCIs was 28 (19%) in PHF and 102 (17%) in EDF. Other outcomes (key timestamps) are pending. Conclusion: Our results show that the 30-day mortality was lowest for patients undergoing PPCI and slightly less for patients receiving pre-hospital fibrinolytic compared to those receiving ED fibrinolytic with no difference in the proportion requiring subsequent rescue PCI. The majority of patients in rural areas received EDF as opposed to PHF; pending results will show if this represents a delay in patient presentation after symptom onset.
Introduction: Recently, intranasal (IN) fentanyl and inhaled nitrous oxide/oxygen (N2O) mixture have been increasingly used for procedural sedation and analgesia (PSA) alone or in combination. There is a lack of data on the efficacy of these combined agents. Methods: The objective was to evaluate the efficacy of IN fentanyl and N2O as PSA for the reduction of mildly-to-moderately displaced fractures and dislocations. We performed a prospective, observational cohort study between September 2014 and October 2015. Patients were recruited at CHU Sainte Justine (Montréal) and Royal Children Hospital (Melbourne, Australia). Patients aged 4 to 18 years were eligible if PSA consisted of IN fentanyl and N2O for the reduction of mildly-to-moderately displaced fractures or dislocations. Patients received at least IN fentanyl 1.5 mcg/kg (100 mcg max) and at least a 50/50% mixture of N2O with oxygen. Primary outcome was the efficacy of PSA measured by the patient assigned Facial Pain Scale-Revised (FPS-R). The Face, Legs, Activity, Cry, Consolability (FLACC) scale was also recorded. Depth of sedation was evaluated using University of Michigan Sedation Scale (UMSS). Adverse events were recorded following criteria of the Consensus Panel on Sedation Research of PERC/PECARN. Additional data concerning satisfaction or discomfort were evaluated via questionnaires, and follow-up telephone calls were made to elicit information on adverse events after discharge. Results: A total of 91 patients aged 9.7 ± 3.0 years were enrolled. There was no difference between the median FPS-R score during the procedure compared to before: Median 2 and 2 (median difference 0 [95% CI 0, 0]), respectively. The FLACC score was higher during the procedure than before: Median 4 and 0 (median difference 2 [95% CI 1, 3]). UMSS was 1 (95% CI 1, 2) during the procedure. 42 (46%) patients had adverse events, all mild: vertigo (20%), nausea (16%)]or vomiting (12%). A total of 85/88 (97%) parents and 82/85 (96%) ED physicians would want the same sedation in another procedure. Conclusion: PSA with IN fentanyl and N2O seems effective in our study, as evaluated by patient assigned FPS-R. Patients were minimally sedated. Adverse events were frequent but mild. Overall, parents and medical staff would want the same agents used in another procedure. Thus, PSA with IN fentanyl and N2O appears to be an attractive option for reduction of mildly displaced fractures or dislocations.
The Universities of Adelaide and Tasmania (UAT) have now collaborated in the preparation of four experiments on British Skylark rockets. Two independent X-ray detectors of total sensitive area 40 cm2 were flown on each of two rocket flights launched in April, 1967. The most significant result of these measurements was the discovery of Cen XR-2 and the measurement of the variation in its intensity and spectrum. The third flight, launched in December 1967, carried three X-ray detectors of total area 140 cm2. One of the main results from this flight, evidence for a new X-ray source at high galactic latitude, will be presented in the following paper.
During 1990 we surveyed the southern sky using a multi-beam receiver at frequencies of 4850 and 843 MHz. The half-power beamwidths were 4 and 25 arcmin respectively. The finished surveys cover the declination range between +10 and −90 degrees declination, essentially complete in right ascension, an area of 7.30 steradians. Preliminary analysis of the 4850 MHz data indicates that we will achieve a five sigma flux density limit of about 30 mJy. We estimate that we will find between 80 000 and 90 000 new sources above this limit. This is a revised version of the paper presented at the Regional Meeting by the first four authors; the surveys now have been completed.
Very sensitive low-noise amplifiers designed to receive transmissions from spacecraft are not necessarily suitable receivers for radio astronomy. In the former case a good signalto- noise ratio is required so that high data rates can be achieved. In the latter the ratio of signal to noise power may be as low as 10-4 and the stability of receiver gain and that of ail sources of noise during long integration times become of equal importance.
This paper describes a novel solution to the problem, which allowed important astronomy to be performed while the ruby maser receivers belonging to the European Space Agency were installed on the Parkes radio telescope for an extended period of time.
It is widely believed that the diffuse X-ray background, observed on several occasions over the energy range from 0.25 keV to above 1 MeV has an extragalactic origin. Evidence for this comes from the generally reported isotropy above several keV [1, 2, 3] and the observed galactic latitude dependence at 0.25 keV, believed to result from the interstellar attenuation of these low energy photons in passage through the Galaxy [4, 5].