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Stationary state degeneracy of open quantum systems with non-abelian symmetries
No full textWe study the null space degeneracy of open quantum systems with multiple non-abelian, strong symmetries. By decomposing the Hilbert space representation of these symmetries into an irreducible representation involving the direct sum of multiple, commuting, invariant subspaces we derive a tight lower bound for the stationary state degeneracy. We apply these results within the context of open quantum many-body systems, presenting three illustrative examples: a fully-connected quantum network, the XXX Heisenberg model and the Hubbard model. We find that the derived bound, which scales at least cubically in the system size the SU(2) symmetric cases, is often saturated. Moreover, our work provides a theory for the systematic block-decomposition of a Liouvillian with non-abelian symmetries, reducing the computational difficulty involved in diagonalising these objects and exposing a natural, physical structure to the steady states—which we observe in our examples
Impact of self-monitoring of blood pressure on processes of hypertension care and long-term blood pressure control
No full textBackground: Self-monitoring of blood pressure (SMBP) improves blood pressure (BP) outcomes at 12-months, but information is lacking on how SMBP affects hypertension care processes and longer-term BP outcomes.
Methods and Results: We pooled individual participant data from four randomized clinical trials of SMBP in the United Kingdom (combined n=2590) with varying intensities of support. Multivariable random effects regression was used to estimate the probability of antihypertensive intensification at 12 months for usual care versus SMBP. Using these data, we simulated 5-year BP control rates using a validated mathematical model. Trial participants were mostly older adults (mean age 66.6 years, standard deviation 9.5), male (53.9%), and predominately white (95.6%); mean baseline BP was 151.8/85.0 mmHg. Compared to usual care, the likelihood of antihypertensive intensification increased with both SMBP with feedback to patient or provider alone (odds ratio 1.8, 95% confidence interval 1.2-2.6) and with telemonitoring or self-management (3.3, 2.5-4.2). Over 5 years, we estimated 33.4% BP control (<140/90 mmHg) with usual care (95% uncertainty interval 27.7%-39.4%). One year of SMBP with feedback to patient or provider alone achieved 33.9% (28.3%-40.3%) BP control and SMBP with telemonitoring or self-management 39.0% (33.1%-45.2%) over 5 years. If SMBP interventions and associated BP control processes were extended to five years, BP control increased to 52.4% (45.4%-59.8 %) and 72.1% (66.5%-77.6%), respectively.
Conclusions: One year of SMBP plus telemonitoring or self-management increases the likelihood of antihypertensive intensification and could improve BP control rates at five years; continuing SMBP for five years could further improve BP control
Port disruptions due to natural disasters: Insights into port and logistics resilience
No full textPorts are located in low-lying coastal and riverine areas making them prone to the physical impacts of natural disasters. The consequential disruptions can potentially propagate through supply chains, resulting in widespread economic losses. Previous studies to quantify the risks of port disruptions have adopted various modelling assumptions about the resilience of individual ports and marine network logistics. However, limited empirical evidence is available to validate these modelling assumptions or to provide deeper understanding of the ways in which operations are adapted during and after disruptions. Here, we use vessel tracking data to analyse past port disruptions due to natural disasters, evaluating 141 incidences of disruptions across 74 ports and 27 disasters. Results show a median disruption duration of six days with a 95th percentile of 22.2 days. All analysed events show multiple ports being affected simultaneously, challenging some of the studies that only focus on single port disruptions. Moreover, we find that the duration of the disruption scales with the severity of the event, with an increment of 1.0 m storm surge or 10 m/s wind speed associated with a two day increase in disruption duration. In contrast to commonplace assumptions in model studies, substitution between ports is rarely observed during short-term disruptions. On the other hand, production recapture happens in practice in many cases of port disruptions. In short, empirical vessel tracking data provides valuable insights for future modelling studies in order to better approximate the extent of the disruption and the potential resilience of the port and maritime network
Reporting of methodological studies in health research: a protocol for the development of the MethodologIcal STudy reportIng Checklist (MISTIC)
No full textINTRODUCTION: Methodological studies (ie, studies that evaluate the design, conduct, analysis or reporting of other studies in health research) address various facets of health research including, for instance, data collection techniques, differences in approaches to analyses, reporting quality, adherence to guidelines or publication bias. As a result, methodological studies can help to identify knowledge gaps in the methodology of health research and strategies for improvement in research practices. Differences in methodological study names and a lack of reporting guidance contribute to lack of comparability across studies and difficulties in identifying relevant previous methodological studies. This paper outlines the methods we will use to develop an evidence-based tool-the MethodologIcal STudy reportIng Checklist-to harmonise naming conventions and improve the reporting of methodological studies. METHODS AND ANALYSIS: We will search for methodological studies in the Cumulative Index to Nursing and Allied Health Literature, Cochrane Library, Embase, MEDLINE, Web of Science, check reference lists and contact experts in the field. We will extract and summarise data on the study names, design and reporting features of the included methodological studies. Consensus on study terms and recommended reporting items will be achieved via video conference meetings with a panel of experts including researchers who have published methodological studies. ETHICS AND DISSEMINATION: The consensus study has been exempt from ethics review by the Hamilton Integrated Research Ethics Board. The results of the review and the reporting guideline will be disseminated in stakeholder meetings, conferences, peer-reviewed publications, in requests to journal editors (to endorse or make the guideline a requirement for authors), and on the Enhancing the QUAlity and Transparency Of health Research (EQUATOR) Network and reporting guideline websites. REGISTRATION: We have registered the development of the reporting guideline with the EQUATOR Network and publicly posted this project on the Open Science Framework (www.osf.io/9hgbq)
Supporting dataset for multi-scale sensorless adaptive optics: application to stimulated emission depletion microscopy
No full textMulti-scale sensorless adaptive optics: application to stimulated emission depletion microscopy
Jacopo Antonello, Aurélien Barbotin, Ee Zhuan Chong, Jens Rittscher, and Martin Booth
https://doi.org/10.1364/OE.393363
This folder contains the raw data acquired throughout the experiments. The data is grouped by figure number in the paper.
TIFF files are in OME-TIFF (https://docs.openmicroscopy.org/ome-model/latest/) format and can be opened with FiJi (https://imagej.net/Fiji/Downloads). The legend for the file name is --. So that xy-3dsted-aoon.tif corresponds to an xy scan along the lateral plane, in 3D STED mode, with adaptive optics (AO) correction applied.
AO log files contain the raw data acquired during the aberration correction experiments. These files are in HDF5 (https://www.hdfgroup.org/solutions/hdf5/) format and can be opened with a variety of applications (https://en.wikipedia.org/wiki/Hierarchical_Data_Format) that support HDF5 version 1.10 or later. The legend for the file name is ao---.h5. So that ao4-05-10-zsted.h5 corresponds to the fourth part of the aberration correction, where Zernike modes from 5 to 10 inclusive are corrected in ZSTED mode. The acquired images are stored at the address /stacks/stacks. The first image corresponds to the initial state of the correction. Next, the images necessary for the PN algorithm are collected. In the last image, the correction computed by the PN algorithm is applied. For each image, the corresponding column vector of Zernike coefficients applied by the DM is found at the address /dmlib/control/ZernikeControl/x
Associational resistance to both insect and pathogen damage in mixed forests is modulated by tree neighbour identity and drought
No full textTree health declines can be caused by interactions between pests and pathogens and many studies have shown a reduction in their damage in mixed species forests compared to monocultures. Yet few authors have considered tree diversity effects on both groups simultaneously. Moreover, it is unclear whether diversity effects on tree pests and pathogens are robust to changes in abiotic conditions, such as drought. We addressed tree diversity effects on foliar insect herbivory, oak powdery mildew and their interaction under contrasting water regimes in a large‐scale tree diversity experiment in SW France. Using an irrigation treatment that alleviated drought conditions, we were able to experimentally assess the effects of tree diversity under contrasting abiotic environments. We surveyed plots along a richness gradient from 1 – 4 tree species, in which a focal study species of oak (Q. robur) was mixed with other oak species (Q. pyrenaica and Q. ilex) and a taller, broadleaved species (Betula pendula). Increasing tree species richness lowered leaf miner abundance, leaf chewer damage and oak powdery mildew infection, consistent with a protective effect of resource dilution. However, richness effects on leaf miners were stronger in irrigated compared to non‐irrigated blocks, indicating that environmental conditions can modulate diversity effects. Separate from the effect of tree species richness, the presence of birch in a plot increased damage by leaf chewers and powdery mildew, but lowered leaf miner damage, suggesting additional tree neighbour identity effects potentially linked to modulation of microclimate. We found a negative association between leaf miner abundance and oak powdery mildew, consistent with antagonism between oak damage agents. Overall, our study illustrates the importance of considering both tree diversity and composition (neighbour identity) in designing forests more resistant to pest and pathogen damage
Peptidomimetic‐based identification of FDA approved compounds inhibiting IRE1 activity
No full textInositol-requiring enzyme 1 (IRE1) is a bifunctional serine/threonine kinase
and endoribonuclease that is a major mediator of the unfolded protein
response (UPR) during endoplasmic reticulum (ER) stress. Tumour cells
experience ER stress due to adverse environmental cues such as hypoxia or
nutrient shortage and high metabolic/protein-folding demand. To cope
with those stresses, cancer cells utilise IRE1 signalling as an adaptive mechanism. Here, we report the discovery of the FDA-approved compounds
methotrexate, cefoperazone, folinic acid and fludarabine phosphate as
IRE1 inhibitors. These were identified through a structural exploration of
the IRE1 kinase domain using IRE1 peptide fragment docking and further
optimisation and pharmacophore development. The inhibitors were verified
to have an impact on IRE1 activity in vitro and were tested for their ability
to sensitise human cell models of glioblastoma multiforme (GBM) to
chemotherapy. We show that all molecules identified sensitise glioblastoma
cells to the standard-of-care chemotherapy temozolomide (TMZ)
Trap states, electric fields, and phase segregation in mixed-halide perovskite photovoltaic devices
No full textMixed-halide perovskites are essential for use in all-perovskite or perovskite–silicon tandem solar cells due to their tunable bandgap. However, trap states and halide segregation currently present the two main challenges for efficient mixed-halide perovskite technologies. Here photoluminescence techniques are used to study trap states and halide segregation in full mixed-halide perovskite photovoltaic devices. This work identifies three distinct defect species in the perovskite material: a charged, mobile defect that traps charge-carriers in the perovskite, a charge-neutral defect that induces halide segregation, and a charged, mobile defect that screens the perovskite from external electric fields. These three defects are proposed to be MA+ interstitials, crystal distortions, and halide vacancies and/or interstitials, respectively. Finally, external quantum efficiency measurements show that photoexcited charge-carriers can be extracted from the iodide-rich low-bandgap regions of the phase-segregated perovskite formed under illumination, suggesting the existence of charge-carrier percolation pathways through grain boundaries where phase-segregation may occur
Active nematics with anisotropic friction: the decisive role of the flow aligning parameter
No full textWe use continuum simulations to study the impact of anisotropic hydrodynamic friction on the emergent flows of active nematics. We show that, depending on whether the active particles align with or tumble in their collectively self-induced flows, anisotropic friction can result in markedly different patterns of motion. In a flow-aligning regime and at high anisotropic friction, the otherwise chaotic flows are streamlined into flow lanes with alternating directions, reproducing the experimental laning state that has been obtained by interfacing microtubule–motor protein mixtures with smectic liquid crystals. Within a flow-tumbling regime, however, we find that no such laning state is possible. Instead, the synergistic effects of friction anisotropy and flow tumbling can lead to the emergence of bound pairs of topological defects that align at an angle to the easy flow direction and navigate together throughout the domain. In addition to confirming the mechanism behind the laning states observed in experiments, our findings emphasise the role of the flow aligning parameter in the dynamics of active nematics