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We investigate the interstellar medium towards seven TeV gamma-ray sources thought to be pulsar wind nebulae using Mopra molecular line observations at 7 mm [CS(1–0), SiO(1–0, v = 0)], Nanten CO(1–0) data and the Southern Galactic Plane Survey/GASS Hi survey. We have discovered several dense molecular clouds co-located to these TeV gamma-ray sources, which allows us to search for cosmic rays coming from progenitor SNRs or, potentially, from pulsar wind nebulae. We notably found SiO(1–0, v = 0) emission towards HESS J1809–193, highlighting possible interaction between the adjacent supernova remnant SNR G011.0–0.0 and the molecular cloud at d ∼ 3.7 kpc. Using morphological features, and comparative studies of our column densities with those obtained from X-ray measurements, we claim a distance d ∼ 8.6 − 9.7kpc for SNR G292.2–00.5, d ∼ 3.5 − 5.6 kpc for PSR J1418–6058 and d ∼ 1.5 kpc for the new SNR candidate found towards HESS J1303–631. From our mass and density estimates of selected molecular clouds, we discuss signatures of hadronic/leptonic components from pulsar wind nebulae and their progenitor SNRs. Interestingly, the molecular gas, which overlaps HESS J1026–582 at d ∼ 5 kpc, may support a hadronic origin. We find however that this scenario requires an undetected cosmic-ray accelerator to be located at d < 10 pc from the molecular cloud. For HESS J1809–193, the cosmic rays which have escaped SNR G011.0–0.0 could contribute to the TeV gamma-ray emission. Finally, from the hypothesis that at most 20% the pulsar spin down power could be converted into CRs, we find that among the studied pulsar wind nebulae, only those from PSR J1809–1917 could potentially contribute to the TeV emission.
Although polyphenols inhibit glucose absorption and transport in vitro, it is uncertain whether this activity is sufficient to attenuate glycaemic response in vivo. We examined this using orange juice, which contains high levels of hesperidin. We first used a combination of in vitro assays to evaluate the potential effect of hesperidin and other orange juice components on intestinal sugar absorption and then tested whether this translated to an effect in healthy volunteers. Hesperidin attenuated transfer of 14C-labelled glucose across differentiated Caco-2/TC7 cell monolayers. The involvement of the sugar transporter GLUT2 was demonstrated by experiments carried out in the absence of Na to exclude the contribution of sodium-glucose linked transporter 1 and further explored by the use of Xenopus laevis oocytes expressing human GLUT2 or GLUT5. Fructose transport was also affected by hesperidin partly by inhibition of GLUT5, while hesperidin, even at high concentration, did not inhibit rat intestinal sucrase activity. We conducted three separate crossover interventions, each on ten healthy volunteers using orange juice with different amounts of added hesperidin and water. The biggest difference in postprandial blood glucose between orange juice and control, containing equivalent amounts of glucose, fructose, sucrose, citric acid and ascorbate, was when the juice was diluted (ΔCmax=–0·5 mm, P=0·0146). The effect was less pronounced when the juice was given at regular strength. Our data indicate that hesperidin can modulate postprandial glycaemic response of orange juice by partial inhibition of intestinal GLUT, but this depends on sugar and hesperidin concentrations.
While Marcel Mauss's landmark essay on The Gift has been vital in social anthropology, inspiring a vast and influential secondary literature, the gift has been much less prominent in archaeological interpretation. This study considers evidence for an ancient Andean gift economy, a system of reciprocal exchanges focused on making people and ensuring group social relations, rather than accumulating wealth/capital. Excavations at Yayno (north highlands, Ancash, Peru) revealed two features dating to the time of the Inkas: 1) a slab-lined cist burial; and 2) an offering deposit containing abundant long-distance trade and sumptuary items. Besides its mountaintop location, the burial's intrusive character and foreign items indicate that the offerings were made to propitiate the place, ruins and their divine aspect. This essay studies the reciprocal acts that led to the offerings, comparing them to gifting patterns in Inka human sacrifices known as capac hucha. The key actors in the exchange were children, divinities, Inka bureaucrats, local leaders and state subjects.
We present observations of 50 deg2 of the Mopra carbon monoxide (CO) survey of the Southern Galactic Plane, covering Galactic longitudes l = 300–350° and latitudes |b| ⩽ 0.5°. These data have been taken at 0.6 arcmin spatial resolution and 0.1 km s−1spectral resolution, providing an unprecedented view of the molecular clouds and gas of the Southern Galactic Plane in the 109–115 GHz J = 1–0 transitions of 12CO, 13CO, C18O, and C17O.
We present a series of velocity-integrated maps, spectra, and position-velocity plots that illustrate Galactic arm structures and trace masses on the order of ~106 M⊙ deg−2, and include a preliminary catalogue of C18O clumps located between l = 330–340°. Together with the information about the noise statistics of the survey, these data can be retrieved from the Mopra CO website and the PASA data store.
Background. Diffuse low-grade gliomas (LGGs) are infiltrative, slow-growing primary brain tumours that remain relatively asymptomatic for long periods of time before transforming into aggressive high-grade gliomas. Surveillance of tumour stability is performed primarily by serial imaging. Methods. We retrospectively identified LGG patients that were managed by observation with numerous (≥8) serial magnetic resonance imaging (MRI) studies. Tumour volumes were measured by manual segmentation on imaging. Demographic information, tumour histopathological data, and radiological interpretations were collected from electronic medical records. MRI radiology reports of tumour volume stability were classified into "growth" and "no growth" interpretations. Results. Of 74 LGG patients, 10 (13.5%) patients were included in the study. A median of 11 MRIs (range, 8-18) over a median of 79.7 months (range, 39.8-113.8 months) were analyzed per patient. Tumour diameter linearly increased at a median rate of 2.17 mm/year. Cox regression analysis showed that initial tumour volume predicted time to clinical intervention, and Mann-Whitney U test found that tumours of patients diagnosed before age 50 grew more slowly. Radiology interpretations that reported "no growth" (n=66) corresponded to a median measured growth of 3.90 mL and 11.0% compared to the comparison scan. Reports of "growth" (n=36) corresponded to median measured volume increases of 9.36 mL and 20.5%. Conclusion. We retrospectively analyzed the natural history of LGGs in serially-imaged patients at a single institution. Comparisons to the literature suggest that this is a subset of particularly slow-growing and low-risk tumours. We also highlight the clinical value of performing accurate LGG volumetric analyses.
It is commonly believed that second language (L2) acquisition of lexical tones presents a major challenge for learners from nontonal language backgrounds. This belief is somewhat at odds with research that consistently shows beginning learners making quick gains through focused tone training, as well as research showing advanced learners achieving near-native performance in tone identification tasks. However, other long-term difficulties related to L2 tone perception may persist, given the additional demands of word recognition and the effects of context. In the current study, we used behavioral and event-related potential (ERP) experiments to test whether perception of Mandarin tones is difficult for advanced L2 learners in isolated syllables, disyllabic words in isolation, and disyllabic words in sentences. Stimuli were more naturalistic and challenging than in previous research. While L2 learners excelled at tone identification in isolated syllables, they performed with very low accuracy in rejecting disyllabic tonal nonwords in isolation and in sentences. We also report ERP data from critical mismatching words in sentences; while L2 listeners showed no significant differences in responses in any condition, trends were not inconsistent with the overall pattern in behavioral results of less sensitivity to tone mismatches than to semantic or segmental mismatches. We interpret these results as evidence that Mandarin tones are in fact difficult for advanced L2 learners. However, the difficulty is not due primarily to an inability to perceive tones phonetically, but instead is driven by the need to process tones lexically, especially in multisyllable words.
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.
HESS J1614–518 and HESS J1616–508 are two tera-electron volt γ-ray sources that are not firmly associated with any known counterparts at other wavelengths. We investigate the distribution of interstellar medium towards the tera-electron volt γ-ray sources using results from a 7-mm-wavelength Mopra study, the Mopra Southern Galactic Plane CO Survey, the Millimetre Astronomer’s Legacy Team-45 GHz survey and [C i] data from the HEAT telescope. Data in the CO(1–0) transition lines reveal diffuse gas overlapping the two tera-electron volt sources at several velocities along the line of sight, while observations in the CS(1–0) transition line reveal several interesting dense gas features. To account for the diffuse atomic gas, archival H i data was taken from the Southern Galactic Plane Survey. The observations reveal gas components with masses ~103 to 105 M⊙ and with densities ~102 to 103 cm−3 overlapping the two tera-electron volt sources. Several origin scenarios potentially associated with the tera-electron volt γ-ray sources are discussed in light of the distribution of the local interstellar medium. We find no strong convincing evidence linking any counterpart with HESS J1614–518 or HESS J1616–508.
A current trend in the aeronautic industry is to increase the wing aspect ratio to enhance aerodynamic efficiency by reducing the induced drag and thus reduce fuel consumption. Despite the associated benefits of a large aspect ratio, such as higher lift-to-drag ratios and range, commercial aircraft usually have a relatively low aspect ratio. This is partially explained by the fact that the wing becomes more flexible with increasing aspect ratio and thus more prone to large deflections, which can cause aeroelastic instability problems such as flutter. In this work, an aeroelastic study is conducted on a rectangular wing model of 20 m span and variable chord for a low subsonic speed condition to evaluate the differences between linear and non-linear static aeroelastic responses. Comparisons between linear and non-linear displacements, natural frequencies and flutter boundary are performed. An in-house non-linear aeroelastic framework was employed for this purpose. In this work, the influence of the aspect ratio and geometric non-linearity (highly deformed states) is assessed in terms of aeroelastic performance parameters: flutter speed and divergence speed. A nearly linear correlation of flutter speed difference (relative to linear analysis results) with vertical-tip displacement difference is observed. The flutter and divergence speeds vary substantially as the wing aspect ratio increases, and the divergence speeds always remain above the flutter speed. Furthermore, the flutter mechanism was observed to change as the wing chord is decreased.
Introduction: Analyzing the charts of patients who have a return visit to an emergency department (ED) requiring hospital admission (termed ‘RV’) is an efficient way to identify adverse events (AEs). Investigating these AEs can inform efforts to improve the quality of care provided. The ED RV Quality Program (RVQP) is a new initiative supported by Ontario’s Ministry of Health and Long-Term Care and managed by Health Quality Ontario. It aims to promote a culture of continuous quality improvement through routine audit/investigation of RVs. Methods: The provincial program is mandatory for high-volume EDs and requires auditing of some 72-hour RVs and all 7-day RVs involving ‘sentinel diagnoses’ (subarachnoid hemorrhage [SAH], acute myocardial infarction [AMI], or pediatric sepsis [PS]). A standardized audit template is followed that includes assessment of the type/severity and underlying causes of AEs, and potential actions for improvement. Results: 73 high-volume EDs and 16 smaller EDs (collectively receiving 90% of all ED visits in Ontario) are participating in the program. Nine months’ data have been released to date, comprising 33,956 RVs (1.05% of 3,235,751 ED visits). Of these, 233 RVs (0.69%) were for a sentinel diagnosis (SAH=11, AMI=191, PS=31). The most common presenting complaint on the index visit was abdominal pain (18%). The most common discharge diagnosis following RV admission was acute appendicitis (3.8%). Conclusion: The ED RVQP aims to improve the quality of care provided in Ontario’s EDs by requiring hospitals to conduct audits of RVs and plan actions for improvement when quality gaps are identified. Participating hospitals have completed hundreds of audits to date.
Background: Functional magnetic resonance imaging (fMRI) is being increasingly used for the preoperative evaluation of patients with brain tumours. Methods: The study is a retrospective chart review investigating the use of clinical fMRI from 2002 through 2013 in the preoperative evaluation of brain tumour patients. Baseline demographic and clinical data were collected. The specific fMRI protocols used for each patient were recorded. Results: Sixty patients were identified over the 12-year period. The tumour types most commonly investigated were high-grade glioma (World Health Organization grade III or IV), low-grade glioma (World Health Organization grade II), and meningioma. Most common presenting symptoms were seizures (69.6%), language deficits (23.2%), and headache (19.6%). There was a predominance of left hemispheric lesions investigated with fMRI (76.8% vs 23.2% for right). The most commonly involved lobes were frontal (64.3%), temporal (33.9%), parietal (21.4%), and insular (7.1%). The most common fMRI paradigms were language (83.9%), motor (75.0%), sensory (16.1%), and memory (10.7%). The majority of patients ultimately underwent a craniotomy (75.0%), whereas smaller groups underwent stereotactic biopsy (8.9%) and nonsurgical management (16.1%). Time from request for fMRI to actual fMRI acquisition was 3.1±2.3 weeks. Time from fMRI acquisition to intervention was 4.9±5.5 weeks. Conclusions: We have characterized patient demographics in a retrospective single-surgeon cohort undergoing preoperative clinical fMRI at a Canadian centre. Our experience suggests an acceptable wait time from scan request to scan completion/analysis and from scan to intervention.
Commercial jets usually have relatively low-aspect-ratio wings, in spite of the associated benefits of increasing the wing aspect-ratio, such as higher lift-to-drag ratios and ranges. This is partially explained by the fact that the wing becomes more flexible by increasing the aspect-ratio that results in higher deflections which can cause aeroelastic instability problems such as flutter. An aeroelastic computational framework capable of evaluating the effects of geometric non-linearities on the aeroelastic performance of high-aspect-ratio wings has been developed and validated using numerical and experimental data. In this work, the aeroelastic performance of a base wing model with 20 m span and 1 m chord is analysed and the effect of changing the wing chord or the taper-ratio is determined. The non-linear static aeroelastic equilibrium solutions are compared in terms of drag polar, root bending moment and natural frequencies, and the change in the flutter speed boundary is assessed as a function of aspect-ratio using a time-marching approach.
Introduction: Accurate and efficient interpretation of prehospital 12-lead electrocardiogram (ECG) in patients with suspected ST-segment elevation myocardial infarction (STEMI) can improve outcomes, especially in rural regions. In the Chaudière-Appalaches region, Quebec, a prehospital serial 12-lead ECG monitoring system is used for remote interpretation of ECG abnormalities by emergency physicians via a telemedicine platform, the Unité de Coordination Clinique des Soins Préhospitaliers d'Urgence (UCCSPU). The objective of the study was to evaluate the use of serial monitoring of dynamic ECG changes in patients with suspected STEMI during emergency medical services (EMS) transport. Methods: A retrospective cohort study with suspected STEMI patients monitored with prehospital serial ECGs was performed from August 2006 to December 2013. The data was extracted from UCCSPU clinical databases and verified by an emergency physician supervisor. During EMS transport, the serial ECG monitoring system automatically produced and transmitted every 2 minutes a 12-lead ECG without artefacts. STEMI criteria were based on the Third Universal Definition of Myocardial Infarction. Dynamic ECG change was defined as an ST-segment elevation or depression that meets diagnostic criteria (eg. initial non STEMI (NSTEMI) changing to STEMI and vice versa). Results: Among the 752 patients identified with suspected STEMI, 728 (96.8%) were included in the study due to missing data. The majority (614/728; 84.3%) had a consistent ST segment without significant dynamic changes throughout transport, of which 521 were identified as STEMI and 93 as NSTEMI. The remaining 114 patients (15.7%) had dynamic ECG changes: 41 (36%) evolved from NSTEMI to STEMI, 40 (35.1%) changed from STEMI to NSTEMI, and 33 (28.9%) had more than one dynamic ST-segment change. Overall, 59 patients (8.1%) had a final STEMI ECG diagnosis after an initial NSTEMI ECG interpretation. Conclusion: In this study, the serial ECG system enabled the remote diagnosis of STEMI in 8.1% of patients during EMS transport following an initial NSTEMI diagnosis. Serial monitoring of dynamic changes can allow for more rapid diversion to primary percutaneous coronary intervention facilities, potentially improving patient outcomes. Further studies are needed to evaluate the clinical impact, and costs and benefits of implementing this technology.
Improved solutions have been obtained for the orbit and equatorial cross-section of Mercury using radar ranging data spanning 22 years. These data have yielded new results on the precession of Mercury’s perihelion and better limits on a possible time variation in the gravitational constant G.
Fronto-limbic structural brain abnormalities have been reported in patients with bipolar disorder (BD), but findings in individuals at increased genetic risk of developing BD have been inconsistent. We conducted a study in adolescents and young adults (12–30 years) comparing measures of fronto-limbic cortical and subcortical brain structure between individuals at increased familial risk of BD (at risk; AR), subjects with BD and controls (CON). We separately examined cortical volume, thickness and surface area as these have distinct neurodevelopmental origins and thus may reflect differential effects of genetic risk.
We compared fronto-limbic measures of grey and white matter volume, cortical thickness and surface area in 72 unaffected-risk individuals with at least one first-degree relative with bipolar disorder (AR), 38 BD subjects and 72 participants with no family history of mental illness (CON).
The AR group had significantly reduced cortical thickness in the left pars orbitalis of the inferior frontal gyrus (IFG) compared with the CON group, and significantly increased left parahippocampal gyral volume compared with those with BD.
The finding of reduced cortical thickness of the left pars orbitalis in AR subjects is consistent with other evidence supporting the IFG as a key region associated with genetic liability for BD. The greater volume of the left parahippocampal gyrus in those at high risk is in line with some prior reports of regional increases in grey matter volume in at-risk subjects. Assessing multiple complementary morphometric measures may assist in the better understanding of abnormal developmental processes in BD.
Impairments in key neuropsychological domains (e.g. working memory, attention) and social cognitive deficits have been implicated as intermediate (endo) phenotypes for bipolar disorder (BD), and should therefore be evident in unaffected relatives.
Neurocognitive and social cognitive ability was examined in 99 young people (age range 16–30 years) with a biological parent or sibling diagnosed with the disorder [thus deemed to be at risk (AR) of developing BD], compared with 78 healthy control (HC) subjects, and 52 people with a confirmed diagnosis of BD.
Only verbal intelligence and affective response inhibition were significantly impaired in AR relative to HC participants; the BD participants showed significant deficits in attention tasks compared with HCs. Neither AR nor BD patients showed impairments in general intellectual ability, working memory, visuospatial or language ability, relative to HC participants. Analysis of BD-I and BD-II cases separately revealed deficits in attention and immediate memory in BD-I patients (only), relative to HCs. Only the BD (but not AR) participants showed impaired emotion recognition, relative to HCs.
Selective cognitive deficits in the capacity to inhibit negative affective information, and general verbal ability may be intermediate markers of risk for BD; however, the extent and severity of impairment in this sample was less pronounced than has been reported in previous studies of older family members and BD cases. These findings highlight distinctions in the cognitive profiles of AR and BD participants, and provide limited support for progressive cognitive decline in association with illness development in BD.
Carbon films deposited by filtered cathodic vacuum arc have been used to form high quality Schottky diodes on p-Si. Energetic deposition with an applied substrate bias of -1 kV and with a substrate temperature of 100 °C has produced carbon diodes with rectification ratios of ∼ 3 × 106, saturation currents of ∼0.02 nA and ideality factors close to unity (n = 1.05). Simulations were used to estimate the effective work function and the thickness of an interfacial mixed (C/SiO2) layer from the current/voltage characteristics of the diodes.