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Externalizing disorders are known to be partly heritable, but the biological pathways linking genetic risk to the manifestation of these costly behaviors remain under investigation. This study sought to identify neural phenotypes associated with genomic vulnerability for externalizing disorders.
One-hundred fifty-five White, non-Hispanic veterans were genotyped using a genome-wide array and underwent resting-state functional magnetic resonance imaging. Genetic susceptibility was assessed using an independently developed polygenic score (PS) for externalizing, and functional neural networks were identified using graph theory based network analysis. Tasks of inhibitory control and psychiatric diagnosis (alcohol/substance use disorders) were used to measure externalizing phenotypes.
A polygenic externalizing disorder score (PS) predicted connectivity in a brain circuit (10 nodes, nine links) centered on left amygdala that included several cortical [bilateral inferior frontal gyrus (IFG) pars triangularis, left rostral anterior cingulate cortex (rACC)] and subcortical (bilateral amygdala, hippocampus, and striatum) regions. Directional analyses revealed that bilateral amygdala influenced left prefrontal cortex (IFG) in participants scoring higher on the externalizing PS, whereas the opposite direction of influence was observed for those scoring lower on the PS. Polygenic variation was also associated with higher Participation Coefficient for bilateral amygdala and left rACC, suggesting that genes related to externalizing modulated the extent to which these nodes functioned as communication hubs.
Findings suggest that externalizing polygenic risk is associated with disrupted connectivity in a neural network implicated in emotion regulation, impulse control, and reinforcement learning. Results provide evidence that this network represents a genetically associated neurobiological vulnerability for externalizing disorders.
To test the hypothesis that long-term care facility (LTCF) residents with Clostridium difficile infection (CDI) or asymptomatic carriage of toxigenic strains are an important source of transmission in the LTCF and in the hospital during acute-care admissions.
A 6-month cohort study with identification of transmission events was conducted based on tracking of patient movement combined with restriction endonuclease analysis (REA) and whole-genome sequencing (WGS).
Veterans Affairs hospital and affiliated LTCF.
The study included 29 LTCF residents identified as asymptomatic carriers of toxigenic C. difficile based on every other week perirectal screening and 37 healthcare facility-associated CDI cases (ie, diagnosis >3 days after admission or within 4 weeks of discharge to the community), including 26 hospital-associated and 11 LTCF-associated cases.
Of the 37 CDI cases, 7 (18·9%) were linked to LTCF residents with LTCF-associated CDI or asymptomatic carriage, including 3 of 26 hospital-associated CDI cases (11·5%) and 4 of 11 LTCF-associated cases (36·4%). Of the 7 transmissions linked to LTCF residents, 5 (71·4%) were linked to asymptomatic carriers versus 2 (28·6%) to CDI cases, and all involved transmission of epidemic BI/NAP1/027 strains. No incident hospital-associated CDI cases were linked to other hospital-associated CDI cases.
Our findings suggest that LTCF residents with asymptomatic carriage of C. difficile or CDI contribute to transmission both in the LTCF and in the affiliated hospital during acute-care admissions. Greater emphasis on infection control measures and antimicrobial stewardship in LTCFs is needed, and these efforts should focus on LTCF residents during hospital admissions.
Research on the cities of the Classical Greek world has traditionally focused on mapping the organisation of urban space and studying major civic or religious buildings. More recently, newer techniques such as field survey and geophysical survey have facilitated exploration of the extent and character of larger areas within urban settlements, raising questions about economic processes. At the same time, detailed analysis of residential buildings has also supported a change of emphasis towards understanding some of the functional and social aspects of the built environment as well as purely formal ones. This article argues for the advantages of analysing Greek cities using a multidisciplinary, multi-scalar framework which encompasses all of these various approaches and adds to them other analytical techniques (particularly micro-archaeology). We suggest that this strategy can lead towards a more holistic view of a city, not only as a physical place, but also as a dynamic community, revealing its origins, development and patterns of social and economic activity. Our argument is made with reference to the research design, methodology and results of the first three seasons of fieldwork at the city of Olynthos, carried out by the Olynthos Project.
During ice-structure interaction, ice will fail in a brittle manner dominated by two processes. The first corresponds to the formation of macrocracks and the consequent spalling-off of large ice pieces. The second includes an intense shear-damage process in zones, termed critical zones, where high pressures are transmitted to the structure. The shear-damage process results in microstructural changes including microcrack formation and recrystallization. A range of tests on laboratory-prepared granular ice have been conducted to determine the fundamental behaviour of ice under various stress states and stress history, particularly as it relates to changes in microstructure. The test series was designed to study three aspects: the intrinsic creep properties of intact, undamaged ice; the enhancement of creep and changes in microstructure due to damage; and the effects of different stress paths. Tests on intact ice with triaxial confining pressures and low deviatoric stresses, aimed at defining the intrinsic creep response in the absence of microcracking, showed that an accelerated creep rate occurred at relatively low deviatoric stresses. Hence, a minimum Creep rate occurred under these conditions. Recrystallization to a smaller grain-size and void formation were observed. Ice damaged uniaxially and triaxially prior to testing showed enhancement of creep under both uniaxial and triaxial loading conditions Creep rates in triaxially damaged ice were found to be non-linear with high deviatoric stresses, corresponding to a power-law dependence of creep rate. Uniaxially damaged specimens contained microcracks parallel to the stressed direction which tended to close under triaxial confinement. Damage under triaxial conditions at low confining pressures produced small recrystallized grains near zones of microcracking. At high confining pressures, a fine-grained recrystallized structure with no apparent cracking was observed uniformly across the specimen. The recrystallization process contributes significantly to the enhanced creep rates found in damaged specimens.
Sodium nitroprusside (SNP) has been reported to rapidly reduce psychotic symptoms in patients with schizophrenia. This has the potential to revolutionize treatment for schizophrenia. In this study, we tested the hypothesis that SNP leads to a reduction in psychotic symptoms and an improvement in spatial working memory (SWM) performance in patients with schizophrenia.
This was a single-centre, randomized, double-blind, placebo-controlled trial performed from 27 August 2014 to 10 February 2016 (clinicaltrials.gov identifier: NCT02176044). Twenty patients with schizophrenia aged 18–60 years with a diagnosis of schizophrenia or schizoaffective disorder were recruited from psychiatric outpatient clinics in the South London and Maudsley NHS Trust, London, UK. Baseline symptoms were measured using the Positive and Negative Syndrome Scale (PANSS) and the 18-item Brief Psychiatric Rating Scale (BPRS-18), and SWM was assessed using the CANTAB computerized test. Participants received either an infusion of SNP (0.5 μg/kg per min for 4 h) or placebo and were re-assessed for symptoms and SWM performance immediately after the infusion, and 4 weeks later.
SNP did not lead to any reduction in psychotic symptoms or improvement in SWM performance compared to placebo.
Although this study was negative, it is possible that the beneficial effects of SNP may occur in patients with a shorter history of illness, or with more acute exacerbation of symptoms.
We report on the results of a UV-Optical spectral monitoring of the bright Seyfert 1 galactic nuclei Mkn 335. This campaign began in June, 1989, and ended in June, 1991. Ultraviolet spectra of fourteen epochs at nearly uniform sampling of 30-day intervals, except when the object was inaccessible from the IUE satellite, have been obtained, of which twelve were coordinated with quasi-simultaneous ground-based optical observations made at Lick Observatory.
We have recently used the atmospheric air-shower Cerenkov technique in an attempt to observe pulsed gamma radiation from two southern pulsars, PSR 0833—45 and MP 0959. Northern hemisphere observers do not agree whether the pulsars CP 0950, CP 1133 and CP 1919 are sources of gamma emission, either pulsed or uniform in time.
The ALFA mission is designed to map the entire sky at frequencies between approximately 0.3 and 30 MHz with angular resolution limited by interstellar and interplanetary scattering. Most of this region of the spectrum is inaccessible from the ground because of absorption and refraction by the Earth’s ionosphere. A wide range of astrophysical questions concerning solar system, galactic, and extragalactic objects could be answered with high resolution images at low frequencies, where absorption effects and coherent emission processes become important and the synchrotron lifetimes of electrons are comparable to the age of the universe.
Results of a spatial stability analysis and of numerical simulations of a “slab” jet in which optically thin radiative cooling is dynamically important are presented. Two different cooling curves are used. Unstable Kelvin-Helmholtz modes are significantly different from the adiabatic limit, and the form of the cooling function strongly affects the results. The numerical simulations are in excellent agreement with the linear stability analysis. In the non-linear regime growth of the surface wave at low frequencies results in sinusoidal oscillation which can disrupt the jet, while non-linear body waves produce low amplitude wiggles within the jet that can result in shocks within the jet. In cooling jets, these shocks can produce dense knots and filaments of cooling gas within the jet, and weak shock “spurs” in the ambient gas. Acceleration of ambient gas can be produced by these “spurs”, or by rapid entrainment if the jet is disrupted. For parameters typical of protostellar jets perturbations with a period of < 100 yrs should excite body waves which produce internal shocks and small amplitude wiggles. The lack of large amplitude wiggles in most observed systems is consistent with the suggestion that jets arise from the inner regions (r < 1 AU) of accretion disks.
Increased temporal and frontal slow-wave delta (1–4 Hz) and theta (4–7
Hz) activities are the most consistent resting-state neural abnormalities
reported in schizophrenia. The frontal lobe is associated with negative
symptoms and cognitive abilities such as attention, with negative
symptoms and impaired attention associated with poor functional
To establish whether frontal dysfunction, as indexed by slowing, would be
associated with functional impairments.
Eyes-closed magnetoencephalography data were collected in 41 participants
with schizophrenia and 37 healthy controls, and frequency-domain source
imaging localised delta and theta activity.
Elevated delta and theta activity in right frontal and right
temporoparietal regions was observed in the schizophrenia
v. control group. In schizophrenia, right-frontal
delta activity was uniquely associated with negative but not positive
symptoms. In the full sample, increased right-frontal delta activity
predicted poorer attention and functional capacity.
Our findings suggest that treatment-associated decreases in slow-wave
activity could be accompanied by improved functional outcome and thus
The third High Energy Astronomical Observatory, HEAO-3 was launched on the 20th Sept., 1979 into a 496 km, 43.6° orbit, and has since been successfully returning data from all three experiments on board. One of these experiments, that intended to study the heavy and ultra heavy nuclei in the cosmic radiation, is described here.
Complementing a multitude of activities around the International Year of Crystallography, we report here on a few resources that are helpful for integrating basic crystallography into interdisciplinary college education. We concentrate on four resources with which we are directly involved. The Crystallography Open Database (COD) features currently more than 295,000 entries and has over the last decade developed into the world’s premier open-access source for the structures of small molecules and small to medium sized unit cell crystals. ‘Educational offshoots’ of the COD with approximately a thousand entries combined provide structural information on small molecules, selected macromolecules, crystal structures, grain boundaries, and crystal morphologies in the well documented Crystallographic Information Framework (CIF) file format. This information can be displayed interactively on the website http://nanocrystallography.research.pdx.edu and freely downloaded. Files that allow for the printing of selected database entries on any 3D printer have been added to this site and are also freely downloadable. These files were created with the programs Cif2VRML and WinXMorph that convert CIF files directly into 3D printing files. Interested college educators are invited to visit our open access crystallography resource portal and suggest other resources that should receive wider exposure over this portal.
Excavations at Tell Brak in 2006–7 explored two key episodes in Mesopotamian political and social history, developing early social complexity in the fifth to fourth millennia BC and the shift from territorial state to early empire in the second millennium BC. Late Chalcolithic complexity is represented in Area TW on the main mound and at the outlying sub-mound of Tell Majnuna, while investigation of the Old Babylonian to Mitanni state-to-empire transition involved excavation in Areas HH and HN (Fig. 1). Both sets of excavations tie into our exploration of larger issues of the creation and maturation of past urban landscapes, for which Tell Brak provides a great depth of data.
We would like once again to express our warmest gratitude to Dr Bassam Jamous, Director General of Antiquities and Museums, to Dr Michel Al-Maqdissi, Director of Excavations, to all their staff in Damascus, and to Sd Abdul Messih Baghdo, Director of the Antiquities Office in Hasseke, for their constant and friendly support. Financial support for the excavations was generously provided by the British School of Archaeology in Iraq, the McDonald Institute for Archaeological Research, Cambridge, the National Geographic Committee for Research and Exploration (2006), the Society of Antiquaries of London (2007), Newnham College, Cambridge and the University of Cambridge. We are extremely grateful to all those who have made this research possible.
The majority of people at ultra high risk (UHR) of psychosis also present with co-morbid affective disorders such as depression or anxiety. The neuroanatomical and clinical impact of UHR co-morbidity is unknown.
We investigated group differences in grey matter volume using baseline magnetic resonance images from 121 participants in four groups: UHR with depressive or anxiety co-morbidity; UHR alone; major depressive disorder; and healthy controls. The impact of grey matter volume on baseline and longitudinal clinical/functional data was assessed with regression analyses.
The UHR-co-morbidity group had lower grey matter volume in the anterior cingulate cortex than the UHR-alone group, with an intermediate effect between controls and patients with major depressive disorder. In the UHR-co-morbidity group, baseline anterior cingulate volume was negatively correlated with baseline suicidality/self-harm and obsessive–compulsive disorder symptoms.
Co-morbid depression and anxiety disorders contributed distinctive grey matter volume reductions of the anterior cingulate cortex in people at UHR of psychosis. These volumetric deficits were correlated with baseline measures of depression and anxiety, suggesting that co-morbid depressive and anxiety diagnoses should be carefully considered in future clinical and imaging studies of the psychosis high-risk state.
We report a study on the wetting and spreading of hydrazine-CZTS solution on a series of solid surfaces. The work of adhesion between a hydrazine solution and soda-lime glass, Si, graphite, ITO, SnO2, ZnO, CdS, In2S3, Cu, Au, Ag, Al, Ni, Mo, and carbon single-walled nanotubes was calculated using observed contact angles and the areas of the interface. The surface roughness of drop-casted CZTS precursor films was lower on surfaces with better hydrazine wettability. This suggests that the surface roughness of solution-processed films can be controlled by altering the wetting behavior of the solution on the substrate.