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Effective community engagement in T3–T4 research is widespread, however, similar stakeholder involvement is missing in T1–T2 research. As part of an effort to embed community stakeholders in T1–T2 research, an academic community partnered team conducted discussion groups with researchers to assess perspectives on (1) barriers/challenges to including community stakeholders in basic science, (2) skills/training required for stakeholders and researchers, and (3) potential benefits of these activities. Engaging community in basic science research was perceived as challenging but with exciting potential to incorporate “real-life” community health priorities into basic research, resulting in a new full-spectrum translational research model.
Recent modelling estimates up to two-thirds of new HIV infections among men who have sex with men occur within partnerships, indicating the importance of dyadic HIV prevention efforts. Although new interventions are available to promote dyadic health-enhancing behaviours, minimal research has examined what factors influence partners’ mutual engagement in these behaviours, a critical component of intervention success. Actor-partner interdependence modelling was used to examine associations between relationship characteristics and several dyadic outcomes theorised as antecedents to health-enhancing behaviours: planning and decision making, communication, and joint effort. Among 270 male-male partnerships, relationship satisfaction was significantly associated with all three outcomes for actors (p = .02, .02, .06 respectively). Latino men reported poorer planning and decision making (actor p = .032) and communication (partner p = .044). Alcohol use was significantly and negatively associated with all outcomes except actors’ planning and decision making (actors: p = .11, .038, .004 respectively; partners: p = .03, .056, .02 respectively). Having a sexual agreement was significantly associated with actors’ planning and decision making (p = .007) and communication (p = .008). Focusing on interactions between partners produces a more comprehensive understanding of male couples’ ability to engage in health-enhancing behaviours. This knowledge further identifies new and important foci for the tailoring of dyadic HIV prevention and care interventions.
We have discovered a well-defined extended conformation of double-stranded DNA, which we call Σ-DNA, using laser-tweezers force-spectroscopy experiments. At a transition force corresponding to free energy change ΔG = 1·57 ± 0·12 kcal (mol base pair)−1 60 or 122 base-pair long synthetic GC-rich sequences, when pulled by the 3′−3′ strands, undergo a sharp transition to the 1·52 ± 0·04 times longer Σ-DNA. Intriguingly, the same degree of extension is also found in DNA complexes with recombinase proteins, such as bacterial RecA and eukaryotic Rad51. Despite vital importance to all biological organisms for survival, genome maintenance and evolution, the recombination reaction is not yet understood at atomic level. We here propose that the structural distortion represented by Σ-DNA, which is thus physically inherent to the nucleic acid, is related to how recombination proteins mediate recognition of sequence homology and execute strand exchange. Our hypothesis is that a homogeneously stretched DNA undergoes a ‘disproportionation’ into an inhomogeneous Σ-form consisting of triplets of locally B-like perpendicularly stacked bases. This structure may ensure improved fidelity of base-pair recognition and promote rejection in case of mismatch during homologous recombination reaction. Because a triplet is the length of a gene codon, we speculate that the structural physics of nucleic acids may have biased the evolution of recombinase proteins to exploit triplet base stacks and also the genetic code.
We have investigated the chemo-dynamical evolution of a Milky Way-like disk galaxy, AqC4, produced by a cosmological simulation integrating a sub-resolution ISM model. We evidence a global inside-out and upside-down disk evolution, that is consistent with a scenario where the “thin disk” stars are formed from the accreted gas close to the galactic plane, while the older “thick disk” stars are originated in situ at higher heights. Also, the bar appears the most effective heating mechanism in the inner disk. Finally, no significant metallicity-rotation correlation has been observed, in spite of the presence of a negative [Fe/H] radial gradient.
We derive and compare kinematic parameters of the Galaxy using the PMA and Gaia TGAS data. Two methods are used in calculations: evaluation of the Ogorodnikov-Milne model (OMM) parameters by the least square method (LSM) and a decomposition on a set of vector spherical harmonics (VSH). We trace dependencies on the distance of the derived parameters including the Oort constants A and B and the rotational velocity of the Galaxy Vrot at the Solar distance for the common sample of stars of mixed spectral composition of the PMA and TGAS catalogues. The distances were obtained from the TGAS parallaxes or from reduced proper motions for fainter stars.
The A, B and Vrot parameters derived from proper motions of both catalogues used show identical behaviour but the values are systematically shifted by about 0.5 mas/yr.
The Oort B parameter derived from the PMA sample of red giants shows gradual decrease with increasing the distance while the Oort A has a minimum at about 2 kpc and then gradually increases.
As for models chosen for calculations, first, we confirm conclusions of other authors about the existence of extra-model harmonics in the stellar velocity field. Secondly, not all parameters of the OMM are statistically significant, and the set of parameters depends on the stellar sample used.
We combined the data from the Gaia DR1 and Two-Micron All Sky Survey (2MASS) catalogues in order to derive the absolute proper motions more than 420 million stars distributed all over the sky in the stellar magnitude range 8 mag < G < 21 mag (Gaia magnitude). To eliminate the systematic zonal errors in position of 2MASS catalogue objects, the 2-dimensional median filter was used. The PMA system of proper motion has been obtained by direct link to 1.6 millions extragalactic sources. The short analysis of the absolute proper motion of the PMA stars Catalogue is presented in this work. From a comparison of this data with same stars from the TGAS, UCAC4 and PPMXL catalogues, the equatorial components of the mutual rotation vector of these coordinate systems are determined.
Increasingly, archaeological research in Amazonia is revealing complex precolonial occupation in areas around riverine confluences. In 2014, the first site-based archaeological investigations were undertaken in Gurupá, Pará, Brazil, a municipality that spans the region of the Xingu-Amazon confluence. The Portuguese controlled access to Amazonia from 1623 onward through a network of settlements organized around Gurupá. Results from extensive excavations of terra preta sites, landscape archaeology, and analysis of ceramic evidence suggest that this was also a precolonial crossroads. Carrazedo, once a booming historical town (Arapijó), sits atop a significantly larger terra preta site. Excavations in historical and precolonial sectors of Carrazedo found well-preserved remains, including a precolonial house terrace complex. The extent of terra preta and earthworks at Carrazedo indicate that the precolonial occupation was more intensive than the colonial-historical period occupation. Regional survey revealed colonial-historical period sites consistently overlying expansive precolonial sites, the density and extent of which suggest a major precolonial center at the Xingu-Amazon confluence. Overall, ecological and landscape modifications appear to have been more intense in the precolonial past than during later periods. Short- and long-distance settlement networks also differed during the two periods. This as-of-yet understudied region promises to shed new light on deep-time human-environment interactions and spatial organization in the humid tropics of Amazonia.
This study compared the prelinguistic communicative behaviors of a boy with developmental delay (aged three years and three months) during structured and low structured interactions with his teacher. Using a videotaped analysis procedure developed by Tait and Wood (1987) four variables (eye contact to the speaker, eye contact to the referent, initiation and turntaking) were investigated. The analysis showed that, in the low structured condition, there was a greater degree of engagement, as measured by increased eye contact overall. More particularly, in this condition there was a greater percentage of eye contact to the referent. In addition to this, the participant took a greater percentage of the conversational turns offered to him by the adult in the low structured condition, although there was no difference between the types of turns taken (vocal, gestural and eye contact). The implications of these results for assessment and intervention are discussed.
Parasites are considered to be an important selective force in host evolution but ecological studies of host-parasite systems are usually short-term providing only snap-shots of what may be dynamic systems. We have conducted four surveys of helminths of bank voles at three ecologically similar woodland sites in NE Poland, spaced over a period of 11 years, to assess the relative importance of temporal and spatial effects on helminth infracommunities. Some measures of infracommunity structure maintained relative stability: the rank order of prevalence and abundance of Heligmosomum mixtum, Heligmosomoides glareoli and Mastophorus muris changed little between the four surveys. Other measures changed markedly: dynamic changes were evident in Syphacia petrusewiczi which declined to local extinction, while the capillariid Aonchotheca annulosa first appeared in 2002 and then increased in prevalence and abundance over the remaining three surveys. Some species are therefore dynamic and both introductions and extinctions can be expected in ecological time. At higher taxonomic levels and for derived measures, year and host-age effects and their interactions with site are important. Our surveys emphasize that the site of capture is the major determinant of the species contributing to helminth community structure, providing some predictability in these systems.
To determine what factors are associated with parental motivation to change body weight in overweight children.
Dunedin, New Zealand.
Two hundred and seventy-one children aged 4–8 years, recruited in primary and secondary care, were identified as overweight (BMI≥85th percentile) after screening. Parents completed questionnaires on demographics; motivation to improve diet, physical activity and weight; perception and concern about weight; parenting; and social desirability, prior to being informed that their child was overweight. Additional measures of physical activity (accelerometry), dietary intake and child behaviour (questionnaire) were obtained after feedback.
Although all children were overweight, only 42 % of parents perceived their child to be so, with 36 % indicating any concern. Very few parents (n 25, 8 %) were actively trying to change the child’s weight. Greater motivation to change weight was observed for girls compared with boys (P=0·001), despite no sex difference in BMI Z-score (P=0·374). Motivation was not associated with most demographic variables, social desirability, dietary intake, parenting or child behaviour. Increased motivation to change the child’s weight was observed for heavier children (P<0·001), those who were less physically active (P=0·002) and more sedentary (P<0·001), and in parents who were more concerned about their child’s weight (P<0·001) or who used greater food restriction (P<0·001).
Low levels of parental motivation to change overweight in young children highlight the urgent need to determine how best to improve motivation to initiate change.
To explore service users' experiences of receiving a diagnosis of schizophrenia and the stigma associated with the diagnostic label. Seven participants were interviewed about their perceptions of these experiences. Interviews were analysed using interpretative phenomenological analysis.
Five superordinate themes resulted from the analysis: (1) avoidance of the diagnosis of schizophrenia; (2) stigma and diagnostic labels; (3) lack of understanding of schizophrenia; (4) managing stigma to maintain normality; (5) being ‘schizophrenic’. These, together with their subthemes, highlighted avoidance of the term schizophrenia by participants and use of alternative terms by professionals, which limited opportunities for understanding the label and challenging associated stigma. Participants strived to maintain normality despite potential stigma.
There is a need to address the process of giving a diagnosis as a phenomenon of consequence within its own terms. Implications relate to how professionals deliver and discuss the diagnosis of schizophrenia.
Objective: To determine whether blood levels of the brain-specific biomarker glial fibrillary acidic protein rise during cardiopulmonary bypass for repair of congenital heart disease. Methods: This is a prospective observational pilot study to characterise the blood levels of glial fibrillary acidic protein during bypass. Children <21 years of age undergoing bypass for congenital heart disease at Johns Hopkins Hospital and Texas Children's Hospital were enrolled. Blood samples were collected during four phases: pre-bypass, cooling, re-warming, and post-bypass. Results: A total of 85 patients were enrolled between October, 2010 and May, 2011. The median age was 0.73 years (range 0.01–17). The median weight was 7.14 kilograms (range 2.2–86.5). Single ventricle anatomy was present in 18 patients (22%). Median glial fibrillary acidic protein values by phase were: pre-bypass: 0 ng/ml (range 0–0.35); cooling: 0.039 (0–0.68); re-warming: 0.165 (0–2.29); and post-bypass: 0.112 (0–0.97). There were significant elevations from pre-bypass to all subsequent stages, with the greatest increase during re-warming (p = 0.0001). Maximal levels were significantly related to younger age (p = 0.03), bypass time (p = 0.03), cross-clamp time (p = 0.047), and temperature nadir (0.04). Peak levels did not vary significantly in those with single ventricle anatomy versus two ventricle repairs. Conclusion: There are significant increases in glial fibrillary acidic protein levels in children undergoing cardiopulmonary bypass for repair of congenital heart disease. The highest values were seen during the re-warming phase. Elevations are significantly associated with younger age, bypass and cross-clamp times, and temperature nadir. Owing to the fact that glial fibrillary acidic protein is the most brain-specific biomarker identified to date, it may act as a rapid diagnostic marker of brain injury during cardiac surgery.
Stable, aqueous, red-to-near infrared emission is critical for the use of silicon nanoparticles (Si NPs) in biological fluorescence assays, but such Si NPs have been difficult to attain. We report a synthesis and surface modification strategy that protects Si NPs and preserves red photoluminescence (PL) in water for more than 6 mo. The Si NPs were synthesized via high temperature reaction, liberated from an oxide matrix, and functionalized via hydrosilylation to yield hydrophobic particles. The hydrophobic Si NPs were phase transferred to water using the surfactant cetyltrimethylammonium bromide (CTAB) with retention of red PL. CTAB apparently serves a double role in providing stable, aqueous, red-emitting Si NPs by (i) forming a hydrophobic barrier between the Si NPs and water and (ii) providing aqueous colloidal stability via the polar head group. We demonstrate preservation of the aqueous red emission of these Si NPs in biological media and examine the effects of pH on emission color.
In an effort to better understand the structural changes occurring during hydrogen loading of erbium target materials, we have performed in situ D2 loading of erbium metal (powder) at temperature (450°C) with simultaneous neutron diffraction analysis. This experiment tracked the conversion of Er metal to the α erbium deuteride (solid-solution) phase and then into the β (fluorite) phase. Complete conversion to ErD2.0 was accomplished at 10 Torr D2 pressure with deuterium fully occupying the tetrahedral sites in the fluorite lattice.
In performance assessments, sorption of radionuclides dissolved in groundwater is mostly handled by the use of fixed Kd values. It has been well known that this approach is unsatisfying. Only during the last few years, however, tools have become available that make it possible to predict the actual Kd value in an aqueous solution that differs from the one in which the sorption properties were measured.
One such approach is surface complexation (SC) that gives a detailed knowledge of the sorption properties. In SC, one tries to find what kinds of sorbed species are available on the surface and the thermodynamics for their formation from species in the bulk aqueous solution. Recently, a different approach, surface phase method (SP), has been developed. In SP, a thin layer including the surface is treated as a separate phase. In the bulk aqueous solution, the surface phase is treated as a virtual component, and from the chemical potential of this component, the sorption properties can be found.
In the paper, we compare advantages and disadvantages of the two kinds of models. We also investigate the differences in predicted sorption properties of a number of radionuclides (Co, Np, Th and U). Furthermore, we discuss under which circumstances, one approach or the other is preferable.