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Carbonate glasses can be formed routinely in the system K2CO3–MgCO3. The enthalpy of formation for one such 0.55K2CO3–0.45MgCO3 glass was determined at 298 K to be 115.00 ± 1.21 kJ/mol by drop solution calorimetry in molten sodium molybdate (3Na2O·MoO3) at 975 K. The corresponding heat of formation from oxides at 298 K was −261.12 ± 3.02 kJ/mol. This ternary glass is shown to be slightly metastable with respect to binary crystalline components (K2CO3 and MgCO3) and may be further stabilized by entropy terms arising from cation disorder and carbonate group distortions. This high degree of disorder is confirmed by 13C MAS NMR measurement of the average chemical shift tensor values, which show asymmetry of the carbonate anion to be significantly larger than previously reported values. Molecular dynamics simulations show that the structure of this carbonate glass reflects the strong interaction between the oxygen atoms in distorted carbonate anions and potassium cations.
Indigenous women and children experience some of the most profound health disparities globally. These disparities are grounded in historical and contemporary trauma secondary to colonial atrocities perpetuated by settler society. The health disparities that exist for chronic diseases may have their origins in early-life exposures that Indigenous women and children face. Mechanistically, there is evidence that these adverse exposures epigenetically modify genes associated with cardiometabolic disease risk. Interventions designed to support a resilient pregnancy and first 1000 days of life should abrogate disparities in early-life socioeconomic status. Breastfeeding, prenatal care and early child education are key targets for governments and health care providers to start addressing current health disparities in cardiometabolic diseases among Indigenous youth. Programmes grounded in cultural safety and co-developed with communities have successfully reduced health disparities. More works of this kind are needed to reduce inequities in cardiometabolic diseases among Indigenous women and children worldwide.
Herbicide resistance is ‘wicked’ in nature; therefore, results of the many educational efforts to encourage diversification of weed control practices in the United States have been mixed. It is clear that we do not sufficiently understand the totality of the grassroots obstacles, concerns, challenges, and specific solutions needed for varied crop production systems. Weed management issues and solutions vary with such variables as management styles, regions, cropping systems, and available or affordable technologies. Therefore, to help the weed science community better understand the needs and ideas of those directly dealing with herbicide resistance, seven half-day regional listening sessions were held across the United States between December 2016 and April 2017 with groups of diverse stakeholders on the issues and potential solutions for herbicide resistance management. The major goals of the sessions were to gain an understanding of stakeholders and their goals and concerns related to herbicide resistance management, to become familiar with regional differences, and to identify decision maker needs to address herbicide resistance. The messages shared by listening-session participants could be summarized by six themes: we need new herbicides; there is no need for more regulation; there is a need for more education, especially for others who were not present; diversity is hard; the agricultural economy makes it difficult to make changes; and we are aware of herbicide resistance but are managing it. The authors concluded that more work is needed to bring a community-wide, interdisciplinary approach to understanding the complexity of managing weeds within the context of the whole farm operation and for communicating the need to address herbicide resistance.
Seven half-day regional listening sessions were held between December 2016 and April 2017 with groups of diverse stakeholders on the issues and potential solutions for herbicide-resistance management. The objective of the listening sessions was to connect with stakeholders and hear their challenges and recommendations for addressing herbicide resistance. The coordinating team hired Strategic Conservation Solutions, LLC, to facilitate all the sessions. They and the coordinating team used in-person meetings, teleconferences, and email to communicate and coordinate the activities leading up to each regional listening session. The agenda was the same across all sessions and included small-group discussions followed by reporting to the full group for discussion. The planning process was the same across all the sessions, although the selection of venue, time of day, and stakeholder participants differed to accommodate the differences among regions. The listening-session format required a great deal of work and flexibility on the part of the coordinating team and regional coordinators. Overall, the participant evaluations from the sessions were positive, with participants expressing appreciation that they were asked for their thoughts on the subject of herbicide resistance. This paper details the methods and processes used to conduct these regional listening sessions and provides an assessment of the strengths and limitations of those processes.
Introduction: Emergency Departments (EDs) are frequently the first point of entry to access health services for First Nation (FN) members. In Alberta, FN members visit EDs at almost double the rate of non-FN persons. Furthermore, preliminary evidence demonstrates differences in ED experience for FN members as compared to the general population. The Alberta First Nations Information Governance Centre, Maskwacis Health Services, Yellowhead Tribal Council, Treaty 8 First Nations of Alberta, and Alberta Health Services are working together to research FN members ED experiences and concerns. Methods: This is participatory research guided by a two-eyed seeing approach that acknowledges the equal value of both Western and Indigenous worldviews. FN and non-FN leaders researchers are full partners in the development of the research project. Six sharing circles will be held in February 2018 across Alberta, with Elders, FN patients, FN and non-FN clinicians and FN and non-FN administrators. Sharing circles are similar to focus groups, but emphasize everyone having a turn to speak and demonstrating respect among participants in accordance with FN protocols. Elders will select the questions for discussion based on topics that arose in initial team meetings. Sharing circle discussions will be audio recorded and transcribed. Analysts will include both Western and Indigenous worldview researchers, who will collaboratively interpret findings. Elders will review, discuss, contextualize and expand upon study findings. The research is also guided by FN principles of Ownership, Control, Access, and Possession of FN information. It is through these principles that First Nation research projects can truly be classified as FN lead and driven. Results: Based on initial team meeting discussions, results of sharing circles are expected to provide insights on issues such as: healing, patient-provider communication (verbal and non-verbal), shared decision making, respect for patient preferences, experiences leading to trust or distrust, understandings of wait times and triage, times when multiple (repeat) ED presentations occur, distances travelled for care, choosing specific EDs when seeking care, impacts of stereotypes about FN patients, and racism and reconciliation. Conclusion: Understanding FN ED experience and bringing FN perspectives to Western conceptions of the goals and provision of ED care are important steps toward reconciliation.
Since 1982 July we have been engaged in a systematic investigation of the milliarcsecond structure of the radio emission from several binary star systems, mainly in the RS CVn class (Hall, 1976). The first few observations utilized the MkII VLBI recording scheme, but no useful data were obtainable because of the relatively low flux levels involved Beginning in 1982 December, we have been using the MkIII system with large telescopes and have successfully detected seven binary systems (UX Arietis, HR 1099, Algol, II Peg, σ Crb, and the distant system LSI 61°303). A summary of the three experiments already completed is given in Table 1.
We report here VLBI observations at four epochs of the source BL Lacertae made with the U.S. VLBI Network (plus Bonn) at 10.65 GHz which show clear evidence of uniform superluminal expansion at v/c = 4.4 ± 0.2 (H0 = 55 km s−1 mpc−1). The maps, which were made every three months from 1981.76 to 1982.75 (Figures 1, 2), were part of an ongoing program of VLBI observations of BL Lacertae at 5 and 10.65 GHz starting in 1980.4, near the beginning of a series of violent flux outbursts (Aller, Hodge, and Aller, 1983; Aller and Aller, 1984). Previous results from earlier epochs have been reported by Mutel, Aller, and Phillips (1981) and Phillips and Mutel (1982).
VLBI observations of bright radio stars have been initiated in an attempt to measure the positions and proper motions of their radio components in order to tie the future HIPPARCOS stellar frame to a VLBI extragalactic reference frame. Through VLBI observations of a sample of 20 known radio stars we have identified 11 stars that should be appropriate for both astrometric VLBI and HIPPARCOS observations. Our measurements indicate that the angular extent of their radio emitting regions is small, i.e. < 3 milliarcseconds for 7 of them. Most of these radio stars belong to the RS Canum Venaticorum class of binary systems.
Symmetric, two-sided morphology seems to argue against relativistic effects dominating compact radio emission. This kind of structure has been reported for a number of sources (Phillips and Mutel 1982; Pearson 1983) based on maps made at one frequency. Various arguments, all indirect, can be made for these sources being (1) Twin regions formed at the ends of jets which emerge from an invisible core, or (2) misidentified core-jet sources wherein the core and an unusually bright knot are wrongly taken to be a “double.” A telling test of both hypotheses is to map the sources in question over an octave or so of frequency. Proponents of view (1) would predict that the two double components will show nearly identical spectral indices and that weak central cores with flat or rising spectra might even be revealed. Champions of view (2) would predict that one end or the other will dominate at high frequencies (the core!) or that complex bridges of emission (the jet!) will be revealed between the components at low frequencies. We have followed our initial discovery of 5 symmetric compact doubles by (A) attempting to enlarge the sample of symmetric sources available to study, and (B) by investigating at 5 GHz those doubles for which the best maps exist at 1.7 GHz.
Radio positions of eight stellar systems have been derived with accuracies of 3 to 300 milliarcseconds from MkIII VLBI observations conducted with multi-station arrays. The best accuracy was obtained during a relatively strong outburst of the RS CVn system HR 5110. The epoch J2000.0 positions are obtained in the Jet Propulsion Laboratory VLBI reference frame of extragalactic radio sources.
The evolution of compact double radio sources is discussed using a model due to Carvahlo (1985). We suggest that for doubles associated with active galaxies, there is a plausible evolutionary sequence from compact doubles to steep-spectrum compact sources to extended (D1) doubles.
BL Lac shows tightly correlated events in flux density and polarization. When the time scale slows enough for VLBI observations to track them, moving features which mimic piston-driven shocks seem to carry the disturbances. Evidence for BL Lac's shocks may ameliorate the difficulties posed by the excessive incidence of superluminal motion among core objects; superluminal motion may arise from any number of conditions combining shocks and optical depth, not just real jet or real component motions.
We present results from a multiwavelength study of the blazar PKS 1954–388 at radio, UV, X-ray, and gamma-ray energies. A RadioAstron observation at 1.66 GHz in June 2012 resulted in the detection of interferometric fringes on baselines of 6.2 Earth-diameters. This suggests a source frame brightness temperature of greater than 2 × 1012 K, well in excess of both equipartition and inverse Compton limits and implying the existence of Doppler boosting in the core. An 8.4-GHz TANAMI VLBI image, made less than a month after the RadioAstron observations, is consistent with a previously reported superluminal motion for a jet component. Flux density monitoring with the Australia Telescope Compact Array confirms previous evidence for long-term variability that increases with observing frequency. A search for more rapid variability revealed no evidence for significant day-scale flux density variation. The ATCA light-curve reveals a strong radio flare beginning in late 2013, which peaks higher, and earlier, at higher frequencies. Comparison with the Fermi gamma-ray light-curve indicates this followed ~ 9 months after the start of a prolonged gamma-ray high-state—a radio lag comparable to that seen in other blazars. The multiwavelength data are combined to derive a Spectral Energy Distribution, which is fitted by a one-zone synchrotron-self-Compton (SSC) model with the addition of external Compton (EC) emission.
Identifying youth who may engage in future substance use could facilitate early identification of substance use disorder vulnerability. We aimed to identify biomarkers that predicted future substance use in psychiatrically un-well youth.
LASSO regression for variable selection was used to predict substance use 24.3 months after neuroimaging assessment in 73 behaviorally and emotionally dysregulated youth aged 13.9 (s.d. = 2.0) years, 30 female, from three clinical sites in the Longitudinal Assessment of Manic Symptoms (LAMS) study. Predictor variables included neural activity during a reward task, cortical thickness, and clinical and demographic variables.
Future substance use was associated with higher left middle prefrontal cortex activity, lower left ventral anterior insula activity, thicker caudal anterior cingulate cortex, higher depression and lower mania scores, not using antipsychotic medication, more parental stress, older age. This combination of variables explained 60.4% of the variance in future substance use, and accurately classified 83.6%.
These variables explained a large proportion of the variance, were useful classifiers of future substance use, and showed the value of combining multiple domains to provide a comprehensive understanding of substance use development. This may be a step toward identifying neural measures that can identify future substance use disorder risk, and act as targets for therapeutic interventions.
The purpose of this study was to evaluate a programme of lesion surgery carried out on patients with treatment-resistant depression (TRD).
This was a retrospective study looking at clinical and psychometric data from 45 patients with TRD who had undergone bilateral stereotactic anterior capsulotomy surgery over a period of 15 years, with the approval of the Mental Health Act Commission (37 with unipolar depression and eight with bipolar disorder). The Beck Depression Inventory (BDI) before and after surgery was used as the primary outcome measure. The Montgomery–Asberg Depression Rating Scale was administered and cognitive aspects of executive and memory functions were also examined. We carried out a paired-samples t test on the outcome measures to determine any statistically significant change in the group as a consequence of surgery.
Patients improved on the clinical measure of depression after surgery by −21.20 points on the BDI with a 52% change. There were no significant cognitive changes post-surgery. Six patients were followed up in 2013 by phone interview and reported a generally positive experience. No major surgical complications occurred.
With the limitations of an uncontrolled, observational study, our data suggest that capsulotomy can be an effective treatment for otherwise TRD. Performance on neuropsychological tests did not deteriorate.
We provide detailed contextual information on 25 14C dates for unusually well-preserved archaeological and paleontological remains from Daisy Cave. Paleontological materials, including faunal and floral remains, have been recovered from deposits spanning roughly the past 16,000 yr, while archaeological materials date back to ca. 10,500 BP. Multidisciplinary investigations at the site provide a detailed record of environmental and cultural changes on San Miguel Island during this time period. This record includes evidence for the local or regional extinction of a number of animal species, as well as some of the earliest evidence for the human use of boats and other maritime activities in the Americas. Data from Daisy Cave contribute to a growing body of evidence that Paleoindians had adapted to a wide variety of New World environments prior to 10,000 PB. Analysis of shell-charcoal pairs, along with isotopic analysis of associated marine shells, supports the general validity of marine shell dating, but also provides evidence for temporal fluctuations in the reservoir effect within the Santa Barbara Channel region.
In September 2009, the Rensselaer County Department of Health investigated an increase in Giardia duodenalis cases. The epidemiological investigation identified that a source of the illness could be a roadside spring located in the eastern part of the county. Epidemiological and environmental health staff conducted a site visit to the roadside spring and found several concerns. Water samples were collected from the roadside spring and sent to the New York State Department of Health for analysis. The water sample results indicated the presence of empty Giardia cysts. Prevention methods occurred and the roadside spring was destroyed. A total of 36 laboratory-confirmed cases of Giardia were identified from this outbreak that included residents of New York State and Massachusetts.
With HST and WFPC2, galaxies in the Medium Deep Survey can be reliably classified to magnitudes I814 ≲ 22.0 in the F814W band, at a mean redshift . The main result is the relatively high proportion (~40%) of objects which are in some way irregular or anomalous, and which are of relevance in understanding the origin of the familiar excess population of faint galaxies. These diverse objects include compact galaxies, apparently interacting pairs, galaxies with superluminous starforming regions and diffuse low surface brightness galaxies of various forms. The ‘irregulars’ and ‘peculiar’ galaxies contribute most of the excess counts in the I-band at our limiting magnitude, and may explain the ‘faint blue galaxy’ problem.
Offspring of parents with bipolar disorder (BD) (BO) are at higher risk of BD than offspring of parents with non-BD psychopathology (NBO), although both groups are at higher risk than offspring of psychiatrically healthy parents (HC) for other affective and psychiatric disorders. Abnormal functioning in reward circuitry has been demonstrated previously in individuals with BD. We aimed to determine whether activation and functional connectivity in this circuitry during risky decision-making differentiated BO, NBO and HC.
BO (n = 29; mean age = 13.8 years; 14 female), NBO (n = 28; mean age = 13.9 years; 12 female) and HC (n = 23; mean age = 13.7 years; 11 female) were scanned while performing a number-guessing reward task. Of the participants, 11 BO and 12 NBO had current non-BD psychopathology; five BO and four NBO were taking psychotropic medications.
A 3 (group) × 2 (conditions: win-control/loss-control) analysis of variance revealed a main effect of group on right frontal pole activation: BO showed significantly greater activation than HC. There was a significant main effect of group on functional connectivity between the bilateral ventral striatum and the right ventrolateral prefrontal cortex (Z > 3.09, cluster-p < 0.05): BO showed significantly greater negative functional connectivity than other participants. These between-group differences remained after removing youth with psychiatric disorders and psychotropic medications from analyses.
This is the first study to demonstrate that reward circuitry activation and functional connectivity distinguish BO from NBO and HC. The fact that the pattern of findings remained when comparing healthy BO v. healthy NBO v. HC suggests that these neuroimaging measures may represent trait-level neurobiological markers conferring either risk for, or protection against, BD in youth.