472 research outputs found
Twist Angle Tuning of Moir\ue9 Exciton Polaritons in van der Waals Heterostructures
Twisted atomically thin semiconductors are characterized by moir\ue9 excitons. Their optical signatures and selection rules are well understood. However, their hybridization with photons in the strong coupling regime for heterostructures integrated in an optical cavity has not been the focus of research yet. Here, we combine an excitonic density matrix formalism with a Hopfield approach to provide microscopic insights into moir\ue9 exciton polaritons. In particular, we show that exciton-light coupling, polariton energy, and even the number of polariton branches can be controlled via the twist angle. We find that these new hybrid light-exciton states become delocalized relative to the constituent excitons due to the mixing with light and higher-energy excitons. The system can be interpreted as a natural quantum metamaterial with a periodicity that can be engineered via the twist angle. Our study presents a significant advance in microscopic understanding and control of moir\ue9 exciton polaritons in twisted atomically thin semiconductors
Social and political mechanisms for establishing ecosystem management objectives
While social values guide the objectives of ecosystem management, successful execution requires a public well-informed on the consequences of alternative decision options. Daniels advocates a group-learning process entitled collaborative learning to achieve this understanding. Agency personnel should assume the roles of educators, facilitators, and managers. The agencies must also open up, meditate, and share decision-making power with the public while avoiding advocacy of any particular interest-group\u27s desires. Policy makers have a role in influencing social values by fostering a nonadversarial politics of cooperation and consensus building
Development of a SelfâManagement TheoryâGuided Discharge Intervention for Parents of Hospitalized Children
Background
Parents of hospitalized children, especially parents of children with complex and chronic health conditions, report not being adequately prepared for selfâmanagement of their child\u27s care at home after discharge. Problem
No theoryâbased discharge intervention exists to guide pediatric nurses\u27 preparation of parents for discharge. Purpose
To develop a theoryâbased conversation guide to optimize nurses\u27 preparation of parents for discharge and selfâmanagement of their child at home following hospitalization. Methods
Two frameworks and one method influenced the development of the intervention: the Individual and Family SelfâManagement Theory, Tanner\u27s Model of Clinical Judgment, and the TeachâBack method. A team of nurse scientists, nursing leaders, nurse administrators, and clinical nurses developed and field tested the electronic version of a nineâdomain conversation guide for use in acute care pediatric hospitals. Conclusions
The theoryâbased intervention operationalized selfâmanagement concepts, added components of nursing clinical judgment, and integrated the TeachâBack method. Clinical Relevance
Development of a theoryâbased intervention, the translation of theoretical knowledge to clinical innovation, is an important step toward testing the effectiveness of the theory in guiding clinical practice. Clinical nurses will establish the practice relevance through future use and refinement of the intervention
A Functional Chemiluminescent Probe for in vivo Imaging of Natural Killer Cell Activity against Tumours
Neighbourhood deprivation across eight decades and late-life cognitive function in the Lothian Birth Cohort 1936: A life-course study
Exciton optics, dynamics, and transport in atomically thin semiconductors
Atomically thin semiconductors such as transition metal dichalcogenide (TMD) monolayers exhibit a very strong Coulomb interaction, giving rise to a rich exciton landscape. This makes these materials highly attractive for efficient and tunable optoelectronic devices. In this Research Update, we review the recent progress in the understanding of exciton optics, dynamics, and transport, which crucially govern the operation of TMD-based devices. We highlight the impact of hexagonal boron nitride-encapsulation, which reveals a plethora of many-particle states in optical spectra, and we outline the most novel breakthroughs in the field of exciton-polaritonics. Moreover, we underline the direct observation of exciton formation and thermalization in TMD monolayers and heterostructures in recent time-resolved, angle-resolved photoemission spectroscopy studies. We also show the impact of exciton density, strain, and dielectric environment on exciton diffusion and funneling. Finally, we put forward relevant research directions in the field of atomically thin semiconductors for the near future
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Travelling for Umrah:destination attributes, destination image, and post-travel intentions
This paper examines the links between cosmopolitanism, self-identity, and a desire for social interaction perceived destination image and behavioural intentions. A model tested using a sample of 538 Iranian visitors to Mecca for the purpose of Umrah. The result from the structural model suggests that destination attributes influence perceived destination image. Further, such tourists are likely to revisit or recommend Islamic destinations if their experience matches their perceived image of the destination. This implies that, while the religious characteristics of the destination remain important, destination managers cannot disregard the tangential, non-religious attributes of a destination which are crucial in order to satisfy more conventional tourist desires. As such, this study suggests that those managing religious travel destinations should endeavour to foster a welcoming image, where experience, interaction and tolerance are at the forefront of the destinationâs offering
Decadal increase in vessel interactions by a scavenging pelagic seabird across the North Atlantic
J.H.D.âs position is funded by an Irish Research Council Enterprise Partnership Scheme (EPSPG/2019/469), M.C. is funded by the H2020 X-Rotor project (101007135), and the majority of GLS devices are funded by the SEATRACK program (seatrack.seapop.no, Norwegian Research Council grant no. 192141). We would like to recognize and thank all those who assisted in the deployment and recovery of GLS devices, too many to mention individually. We are indebted to Pat and Liezl Grattan-Bellew for accommodating fieldwork on Little Saltee, Orkney Islands Council for access to Eynhallow, the landowners at Laxamyri for access to the Skjalfandi colony, and the Norwegian Armed Forces for support and accommodation on Jan Mayen. Particular thanks to Françoise AmĂ©lineau and Ewan Edwards for helpful input during discussions on this topic at an early stage, and to Vegard BrĂ„then for collating, curating, and delivering the data for analysis. Thanks to the two anonymous reviewers for exceptionally helpful and constructive feedback.Peer reviewedPublisher PD
Draft genomes of three closely related low light-adapted <i>Prochlorococcus</i>
OBJECTIVES: The marine cyanobacterium Prochlorococcus is a critical part of warm ocean ecosystems and a model for studying microbial evolution and ecology. To expand the representation of this organism's vast wild diversity in sequence collections, we performed a set of isolation efforts targeting low light-adapted Prochlorococcus. Three genomes resulting from this larger body of work are described here.DATA DESCRIPTION: We present draft-quality Prochlorococcus genomes from enrichment cultures P1344, P1361, and P1363, sampled in the North Pacific. The genomes were built from Illumina paired reads assembled de novo. Supporting datasets of raw reads, assessments, and sequences from co-enriched heterotrophic marine bacteria are also provided. These three genomes represent members of the low light-adapted LLIV Prochlorococcus clade that are closely related, with 99.9% average nucleotide identity between pairs, yet vary in gene content. Expanding the powerful toolkit of Prochlorococcus genomes, these sequences provide an opportunity to study fine-scale variation and microevolutionary processes.</p
Case report: Acute necrotizing encephalopathy: a report of a favorable outcome and systematic meta-analysis of outcomes with different immunosuppressive therapies
Acute Necrotizing Encephalopathy (ANE) is a condition characterized by symmetric, bilateral lesions affecting the thalamus and potentially other areas of the brain following an acute febrile illness. It manifests clinically as abrupt development of encephalopathy, or alteration in mental status that often includes development of seizures and progression to coma. Treatment strategies combine immunosuppressive therapies and supportive care with varying levels of recovery, however there are no universally accepted, data-driven, treatment algorithms for ANE. We first report a case of a previously healthy 10-year-old female with acute onset diplopia, visual hallucinations, lethargy, and seizures in the setting of subacute non-specific viral symptoms and found to have bilateral thalamic and brainstem lesions on MRI consistent with ANE. She was treated with a combination of immunomodulatory therapies and ultimately had a good outcome. Next, we present a meta-analysis of 10 articles with a total of 158 patients meeting clinical and radiographic criteria for ANE. Each article reported immunosuppressive treatments received, and associated morbidity or mortality outcome for each individual patient. Through our analysis, we confirm the effectiveness of high-dose, intravenous, methylprednisolone (HD-IV-MP) therapy implemented early in the disease course (initiation within 24âh of neurologic symptom onset). There was no significant difference between patients treated with and without intravenous immunoglobulin (IVIG). There was no benefit of combining IVIG with early HD-IV-MP. There is weak evidence suggesting a benefit of IL-6 inhibitor tocilizumab, especially when used in combination with early HD-IV-MP, though this analysis was limited by sample size. Finally, plasma exchange (PLEX) improved survival. We hope this meta-analysis will be useful for clinicians making treatment decisions for patients with this potentially devastating condition
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