249 research outputs found
Combining microscopic and macroscopic probes to untangle the single-ion anisotropy and exchange energies in an S=1 quantum antiferromagnet
The magnetic ground state of the quasi-one-dimensional spin-1 antiferromagnetic chain is sensitive to the relative sizes of the single-ion anisotropy (D) and the intrachain (J) and interchain (J') exchange interactions. The ratios D/J and J'/J dictate the material's placement in one of three competing phases: a Haldane gapped phase, a quantum paramagnet and an XY-ordered state, with a quantum critical point at their junction. We have identified [Ni(HF)2(pyz)_2]SbF6, where pyz = pyrazine, as a rare candidate in which this behavior can be explored in detail. Combining neutron scattering (elastic and inelastic) in applied magnetic fields of up to 10~tesla and magnetization measurements in fields of up to 60~tesla with numerical modeling of experimental observables, we are able to obtain accurate values of all of the parameters of the Hamiltonian [D = 13.3(1)~K, J = 10.4(3)~K and J' = 1.4(2)~K], despite the polycrystalline nature of the sample. Density-functional theory calculations result in similar couplings (J = 9.2~K, J' = 1.8~K) and predict that the majority of the total spin population resides on the Ni(II) ion, while the remaining spin density is delocalized over both ligand types. The general procedures outlined in this paper permit phase boundaries and quantum-critical points to be explored in anisotropic systems for which single crystals are as yet unavailable
Genetic association study of QT interval highlights role for calcium signaling pathways in myocardial repolarization.
The QT interval, an electrocardiographic measure reflecting myocardial repolarization, is a heritable trait. QT prolongation is a risk factor for ventricular arrhythmias and sudden cardiac death (SCD) and could indicate the presence of the potentially lethal mendelian long-QT syndrome (LQTS). Using a genome-wide association and replication study in up to 100,000 individuals, we identified 35 common variant loci associated with QT interval that collectively explain ∼8-10% of QT-interval variation and highlight the importance of calcium regulation in myocardial repolarization. Rare variant analysis of 6 new QT interval-associated loci in 298 unrelated probands with LQTS identified coding variants not found in controls but of uncertain causality and therefore requiring validation. Several newly identified loci encode proteins that physically interact with other recognized repolarization proteins. Our integration of common variant association, expression and orthogonal protein-protein interaction screens provides new insights into cardiac electrophysiology and identifies new candidate genes for ventricular arrhythmias, LQTS and SCD
Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial
Background
Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy
The state of the Martian climate
60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes
Recommended from our members
Effectiveness of psychoeducational interventions for family carers of people with psychosis: A systematic review and meta-analysis.
Psychoeducational interventions for family carers of people with psychosis are effective for improving compliance and preventing relapse. Whether carers benefit from these interventions has been little explored. This systematic review investigated the effectiveness of psychoeducation for improving carers' outcomes, and potential treatment moderators. We searched for randomised controlled trials (RCTs) published in English or Chinese in eight databases. Carers' outcomes included wellbeing, quality of life, global morbidities, burden, and expressed emotion. Thirty-two RCTs were included, examining 2858 carers. Intervention duration ranged from 4 to 52weeks, and contact times ranged from 6 to 42hours. At post intervention, findings were equivocal for carers' wellbeing (SMD 0.103, 95% CI -0.186 to 0.392). Conversely, psychoeducation was superior in reducing carers' global morbidities (SMD -0.230, 95% CI -0.386 to -0.075), perceived burden (SMD -0.434, 95% CI -0.567 to -0.31), negative caregiving experiences (SMD -0.210, 95% CI -0.396 to -0.025) and expressed emotion (SMD -0.161, 95% CI -0.367 to -0.045). The lack of available data precluded meta-analysis of outcomes beyond short-term follow-up. Meta-regression revealed no significant associations between intervention modality, duration, or contact time and outcomes. Further research should focus on improving carers' outcomes in the longer-term and identifying factors to optimise intervention design
Recommended from our members
Effectiveness of psychoeducational interventions for family carers of people
Psychoeducational interventions for family carers of people with psychosis are effective for improving compliance and preventing relapse. Whether carers benefit from these interventions has been little explored. This systematic review investigated the effectiveness of psychoeducation for improving carers' outcomes, and potential treatment moderators. We searched for randomised controlled trials (RCTs) published in English or Chinese in eight databases. Carers' outcomes included wellbeing, quality of life, global morbidities, burden, and expressed emotion. Thirty-two RCTs were included, examining 2858 carers. Intervention duration ranged from 4 to 52 weeks, and contact times ranged from 6 to 42 hours. At post intervention, findings were equivocal for carers' wellbeing (SMD 0.103, 95% CI − 0.186 to 0.392). Conversely, psychoeducation was superior in reducing carers' global morbidities (SMD − 0.230, 95% CI − 0.386 to − 0.075), perceived burden (SMD − 0.434, 95% CI − 0.567 to − 0.31), negative caregiving experiences (SMD − 0.210, 95% CI − 0.396 to − 0.025) and expressed emotion (SMD − 0.161, 95% CI − 0.367 to − 0.045). The lack of available data precluded meta-analysis of outcomes beyond short-term follow-up. Meta-regression revealed no significant associations between intervention modality, duration, or contact time and outcomes. Further research should focus on improving carers' outcomes in the longer-term and identifying factors to optimise intervention design
Allopurinol versus usual care in UK patients with ischaemic heart disease (ALL-HEART) : a multicentre, prospective, randomised, open-label, blinded-endpoint trial
Funding Information: ISM reports research grants from Menarini, EMA, Sanofi, Health Data Research UK, the British Heart Foundation, and Innovative Medicines Initiative; institutional consultancy income from AstraZeneca outside the submitted work; and personal income from AstraZeneca and Amgen outside the submitted work. TMM reports grants from Menarini/Ipsen/Teijin and Merck Sharp & Dohme outside the submitted work, and personal income for consultancy from Novartis and AstraZeneca outside the submitted work, and is a trustee of the Scottish Heart Arterial Risk Prevention Society. AGB reports personal income from Novartis, Mylan, AstraZeneca, Bayer, Daiichi-Sankyo, Boehringer, Pfizer, Galderma, Zambon, and Novo-Nordisk outside the submitted work. ADS and the University of Dundee hold a European patent for the use of xanthine oxidase inhibitors in treating chest pain in angina pectoris. AW declares personal income for consultancy from AbbVie, Akcea, Albireo, Alexion, Allergan, Amarin, Apsara, Arena, Astellas, AstraZeneca, Autolus, Bayer, Biocryst, Biogen, Biomarin, Bristol Myers Squibb, Boehringer Ingelheim, Calico, Celgene, Chiesi, Daiichi Sankyo, Diurnal, Elsai, Eli Lilly, Ferring, Galapagos, Gedeon Richter, Gilead, GlaxoSmithKline, GW Pharma, Idorsia, Incyte, Intercept, Ionis, Ipsen, Janssen, Jazz, Jcyte, Kite Gilead, LEK, Leo Pharma, Les Laboratoires Servier, Lundbeck, Merck (Merck Sharp & Dohme), Merck-Serono, Mitenyi, Mundibiopharma, Mustang Bio, Mylan, Myovant, Norgine, Novartis, Novo Nordisk, Orchard, Paion, Pfizer, Pierre Fabre, PTC, RegenXBio, Rhythm, Sanofi, Santen, Sarepta, SeaGen, Shionogi, Sigmatec, SOBI, Takeda, Tanaya, UCB, and Vertex outside the submitted work. JST declares research funding from the UK National Institute for Health and Care Research (NIHR) and NHS England outside the submitted work and membership of a UK National Institute for Health and Care Excellence guideline committee on management of atrial fibrillation. All other authors declare no competing interests. Funding Information: This study was funded by the NIHR Health Technology Assessment programme (HTA 11/36/41 to ISM, IF, CJH, LW, ADS, AGB, AJA, AW, JST, and TMM). The views expressed are those of the authors and not necessarily those of the NIHR or the UK Department of Health and Social Care. The study was supported by the Scottish Primary Care Research Network, Support for Science Scotland (Grampian, Highlands, Tayside, Fife, Forth Valley, Greater Glasgow and Clyde, Lothian, Ayrshire and Arran, Dumfries and Galloway, and Lanarkshire), and the NIHR Local Clinical Research Networks (East Midlands, West Midlands, Eastern, North Thames, Yorkshire and Humber, North East and North Cumbria, North West Coast, Kent, Surrey and Sussex, and South West Peninsula), which assisted with recruitment and other study activities. We thank Public Health Scotland and NHS Digital for providing data linkage. We thank all the participants, physicians, nurses, and other staff who participated in the ALL-HEART study. Funding Information: This study was funded by the NIHR Health Technology Assessment programme (HTA 11/36/41 to ISM, IF, CJH, LW, ADS, AGB, AJA, AW, JST, and TMM). The views expressed are those of the authors and not necessarily those of the NIHR or the UK Department of Health and Social Care. The study was supported by the Scottish Primary Care Research Network, Support for Science Scotland (Grampian, Highlands, Tayside, Fife, Forth Valley, Greater Glasgow and Clyde, Lothian, Ayrshire and Arran, Dumfries and Galloway, and Lanarkshire), and the NIHR Local Clinical Research Networks (East Midlands, West Midlands, Eastern, North Thames, Yorkshire and Humber, North East and North Cumbria, North West Coast, Kent, Surrey and Sussex, and South West Peninsula), which assisted with recruitment and other study activities. We thank Public Health Scotland and NHS Digital for providing data linkage. We thank all the participants, physicians, nurses, and other staff who participated in the ALL-HEART study. Publisher Copyright: © 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licensePeer reviewedPublisher PD
B2B Channel Partner Programs: Disentangling Indebtedness from Gratitude
Many suppliers invest heavily in channel partner programs that incentivize selling and learning. The authors conduct a multi-wave field study to investigate the roles of indebtedness and gratitude in transforming these investments into returns. The results show that indebtedness has negative effects on commitment to the supplier, as well as the reseller's sales effort. Gratitude however attenuates the effects of indebtedness on sales effort and commitment, and thus offers a buffer against indebtedness' negative effects. Indebtedness and gratitude thus play key roles in channel partner programs. In addition, the results highlight the importance of perceived motives as they differentially predict these two states. Benevolent motives are found to increase gratitude, though ulterior motives do not detract from it. Ulterior motives do however increase indebtedness. Finally, the results also reveal how entitlement negatively impacts channel partner programs: It decreases the positive effect of perceived program value on partner gratitude while increasing the effect of ulterior motives on indebtedness. This study thus assesses the simultaneous yet contrasting role of gratitude and indebtedness, as well as the complexity associated with realizing the full benefits of channel partner programs. The findings have implications for suppliers, marketers, and further research
Causes of endemic radiation in the Caribbean: evidence from the historical biogeography and diversification of the butterfly genus Calisto(Nymphalidae: Satyrinae: Satyrini)
Identification of Novel High-Frequency DNA Methylation Changes in Breast Cancer
Recent data have revealed that epigenetic alterations, including DNA methylation and chromatin structure changes, are among the earliest molecular abnormalities to occur during tumorigenesis. The inherent thermodynamic stability of cytosine methylation and the apparent high specificity of the alterations for disease may accelerate the development of powerful molecular diagnostics for cancer. We report a genome-wide analysis of DNA methylation alterations in breast cancer. The approach efficiently identified a large collection of novel differentially DNA methylated loci (∼200), a subset of which was independently validated across a panel of over 230 clinical samples. The differential cytosine methylation events were independent of patient age, tumor stage, estrogen receptor status or family history of breast cancer. The power of the global approach for discovery is underscored by the identification of a single differentially methylated locus, associated with the GHSR gene, capable of distinguishing infiltrating ductal breast carcinoma from normal and benign breast tissues with a sensitivity and specificity of 90% and 96%, respectively. Notably, the frequency of these molecular abnormalities in breast tumors substantially exceeds the frequency of any other single genetic or epigenetic change reported to date. The discovery of over 50 novel DNA methylation-based biomarkers of breast cancer may provide new routes for development of DNA methylation-based diagnostics and prognostics, as well as reveal epigenetically regulated mechanism involved in breast tumorigenesis
- …