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Abstract Engineering conduction-band valley couplings is a key challenge for Si-based spin qubits. Recent work has shown that the most reliable method for enhancing valley couplings entails adding Ge concentration oscillations to the quantum well. However, ultrashort oscillation periods are difficult to grow, while long oscillation periods do not provide useful improvements. Here, we show that the main benefits of short-wavelength oscillations can be achieved in long-wavelength structures through a second-order coupling process involving Brillouin-zone folding induced by shear strain. We finally show that such strain can be achieved through common fabrication techniques, making this an exceptionally promising system for scalable quantum computing.

Abstract Background There are persistent racial and ethnic health disparities in end-of-life health outcomes in the United States. African American patients are less likely than White patients to access palliative care, enroll in hospice care, have documented goals of care discussions with their healthcare providers, receive adequate symptom control, or die at home. We developed Community Health Worker Intervention for Disparities in Palliative Care (DeCIDE PC) to address these disparities. DeCIDE PC is an integrated community health worker (CHW) palliative care intervention that uses community health workers (CHWs) as care team members to enhance the receipt of palliative care for African Americans with advanced cancer. The overall objectives of this study are to (1) assess the effectiveness of the DeCIDE PC intervention in improving palliative care outcomes amongst African American patients with advanced solid organ malignancy and their informal caregivers, and (2) develop generalizable knowledge on how contextual factors influence implementation to facilitate dissemination, uptake, and sustainability of the intervention. Methods We will conduct a multicenter, randomized, assessor-blind, parallel-group, pragmatic, hybrid type 1 effectiveness-implementation trial at three cancer centers across the United States. The DeCIDE PC intervention will be delivered over 6 months with CHW support tailored to the individual needs of the patient and caregiver. The primary outcome will be advance care planning. The treatment effect will be modeled using logistic regression. The secondary outcomes are quality of life, quality of communication, hospice care utilization, and patient symptoms. Discussion We expect the DeCIDE PC intervention to improve integration of palliative care, reduce multilevel barriers to care, enhance clinic and patient linkage to resources, and ultimately improve palliative care outcomes for African American patients with advanced cancer. If found to be effective, the DeCIDE PC intervention may be a transformative model with the potential to guide large-scale adoption of promising strategies to improve palliative care use and decrease disparities in end-of-life care for African American patients with advanced cancer in the United States. Trial registration Registered on ClinicalTrials.gov (NCT05407844). First posted on June 7, 2022.

Public and patient involvement (PPI) has been identified as an increasingly desired and, often, required component of trial methodology-leading to higher quality, more accessible and relevant clinical research, alongside increased recruitment, funding success and insight into research impact. However, despite the great variety of frameworks and checklists available for assessing PPI, most are limited with respect to important features (e.g. applicable in specific contexts only, fail to clarify what should be assessed and reported, lack the necessary comprehensiveness or are biased in favour of researcher reporting). Thus, the current research aimed to address such limitations through the development of a new checklist, the EPPIIC, through review, thematic analysis and 'meta-evaluation' in conjunction with PPI engagement. Upon completion of the EPPIIC, three thematic 'sub-scales' emerged: (1) Policy & Practice, (2) Participatory Culture and (3) Influence & Impact. All findings are presented and discussed in light of theory and research. Notably, findings recommend EPPIIC as a useful means of assessing PPI in future trials.

Abstract Background Cognitive difficulties experienced by people with multiple sclerosis (MS) impact on quality of life and daily functioning, from childcare and work to social and self-care activities. The Cognitive Occupation-Based programme for people with MS (COB-MS) was developed as a holistic, individualised cognitive rehabilitation intervention to address the wide-ranging symptoms and functional difficulties that present in MS, including the ability to maintain employment, social activities, home management and self-care. The aim of the research is to evaluate the feasibility and preliminary efficacy of COB-MS for people with MS. Methods Due to the impacts of COVID-19, trial activities that were planned for in-person delivery were completed remotely. One hundred and twenty people with MS will be assigned to participate in either the COB-MS programme or a treatment-as-usual, wait-list control group as part of this single-blind, cluster-randomised controlled feasibility and preliminary efficacy trial of the COB-MS programme. The COB-MS group will participate in an eight-session occupational-based cognitive rehabilitation programme over 9 weeks. The COB-MS intervention was planned for in-person delivery but was delivered online by occupational therapists to small groups of people with MS. The primary outcome measure is the Goal Attainment Scaling at 12 weeks. Participants will be assessed pre-intervention, post-intervention, 12 weeks post-intervention and 6 months post-intervention. Qualitative evaluations of participants’ perspectives will also be examined as part of the feasibility study. Data, due to be collected in-person, was collected online or by post. The original study design, including the statistical analysis plan, remains unchanged despite the shift to a remote trial conduct. Discussion Results will provide recommendations for a future definitive trial of COB-MS, with respect to both feasibility and preliminary, clinical efficacy. Trial registration ISRCTN ISRCTN11462710 . Registered on 9 September 2019 and updated on 23 September 2020 to account for changes outlined here.

Quantum-dot spin qubits in Si/SiGe quantum wells require a large and uniform valley splitting for robust operation and scalability. Here the authors introduce and characterize a new heterostructure with periodic oscillations of Ge atoms in the quantum well, which could enhance the valley splitting.

Semiconductor qubit devices suffer from the drift of important device parameters as they are operated. The most important example is a shift in qubit operating frequencies. This effect appears to be directly related to the heating of the system as gate operations are applied. We show that the main features of this phenomenon can be explained by the two-level systems that can also produce charge noise if these systems are considered to form an interacting random-field glass. The most striking feature of the theory is that the frequency shift can be nonmonotonic in temperature. The success of the theory and the questions it raises considerably narrow the possible models for the two-level systems.

Abstract Electron spin qubits are a promising platform for quantum computation. Environmental noise impedes coherent operations by limiting the qubit relaxation (T 1) and dephasing (T ϕ ) times. There are multiple sources of such noise, which makes it important to devise experimental techniques that can detect the spatial locations of these sources and determine the type of source. In this paper, we propose that anisotropy in T 1 and T ϕ with respect to the direction of the applied magnetic field can reveal much about these aspects of the noise. We investigate the anisotropy patterns of charge noise, evanescent-wave Johnson noise, and hyperfine noise in hypothetical devices. It is necessary to have a rather well-characterized sample to get the maximum benefit from this technique. The general anisotropy patterns are elucidated. We calculate the expected anisotropy for a particular model of a Si/SiGe quantum dot device.

Abstract Background Eligibility guidelines in research trials are necessary to minimise confounds and reduce bias in the interpretation of potential treatment effects. There is limited extant research investigating how being deemed ineligible for such trials might impact patients’ perceptions of themselves and of research. Better understanding of the impact of patient ineligibility could enhance design and implementation of future research studies. Methods Eight semi-structured telephone interviews were conducted to explore the impact of ineligibility on self-perceptions; perceptions regarding the nature of research; and the likelihood of expressing interest in future research. Data were collected and analysed thematically through inductive, interpretive phenomenological analysis (IPA). Results Five themes emerged regarding the experience of being deemed ineligible: (1) Being deemed ineligible is emotion and reaction evoking; (2) ‘Doing your bit’: Helping others and increasing the value of research; (3) Communication of ineligibility; (4) Appreciation for those who express interest; and (5) Subsequent perceptions and attitudes towards research. Conclusions The results suggest that being deemed ineligible can elicit negative emotional outcomes but is not likely to change perceptions of or attitudes towards research, possibly due to a desire to help similar others. Ineligibility can impact future participation in some cases, thus reducing the recruitment pool for subsequent research studies. Recommendations are provided to help minimise this risk. Advising of ineligibility in a personal way is recommended: with enhanced clarity regarding the reasoning behind the decision; providing opportunities to ask questions; and ensuring that appreciation for the patient’s time and interest are communicated.

The quantum approximate optimization algorithm (QAOA) is a promising method for solving certain classical combinatorial optimization problems on near-term quantum devices. When employing the QAOA to 3-SAT and Max-3-SAT problems, the quantum cost exhibits an easy-hard-easy or easy-hard pattern, respectively, as the clause density is changed. The quantum resources needed in the hard-region problems are out of reach for current noisy intermediate-scale quantum (NISQ) devices. We show by numerical simulations with up to 14 variables and analytical arguments that the adaptive-bias QAOA (ab-QAOA) greatly improves performance in the hard region of the 3-SAT problems and hard region of the Max-3-SAT problems. For similar accuracy, on average, ab-QAOA needs 3 levels for 10-variable 3-SAT problems as compared to 22 for QAOA. For 10-variable Max-3-SAT problems, the numbers are 7 levels and 62 levels. The improvement comes from a more targeted and more limited generation of entanglement during the evolution. We demonstrate that classical optimization is not strictly necessary in the ab-QAOA since local fields are used to guide the evolution. This leads us to propose an optimization-free ab-QAOA that can solve the hard-region 3-SAT and Max-3-SAT problems effectively with significantly fewer quantum gates as compared to the original ab-QAOA. Our work paves the way for realizing quantum advantages for optimization problems on NISQ devices.

Abstract Background Cognitive difficulties experienced by people with multiple sclerosis (MS) impact their quality of life and daily functioning, from childcare and work, to social and self-care activities. Despite the high prevalence of cognitive difficulties seen in MS, there is a lack of developed programmes that target cognition, while also supporting patients by helping them to function well in everyday life. The Cognitive Occupation-Based programme for people with MS (COB-MS) was developed as a holistic, individualised cognitive rehabilitation intervention. It addresses the wide-ranging symptoms and functional difficulties that present in MS, including the ability to maintain employment, social activities, home management and self-care. The aim of the current research is to evaluate the feasibility and preliminary efficacy of COB-MS for people with MS. The focus is on feasibility outcomes as well as functioning associated with cognitive difficulty and secondary outcomes related to cognition, fatigue and quality of life. Methods One hundred and twenty people with MS will be assigned to participate in either the COB-MS programme or a treatment as usual, wait-list control group as part of this single-blind, cluster-randomised controlled feasibility and preliminary efficacy trial of the COB-MS programme. The COB-MS group will participate in an eight-session occupational-based cognitive rehabilitation programme over 9 weeks. The primary outcome measure is the goal attainment scaling at 12 weeks. Participants will be assessed pre-intervention, post-intervention and at 12 weeks post-intervention and 6 months post-intervention. Qualitative evaluations of participants’ perspectives will also be examined as part of the feasibility study. Discussion Results will provide recommendations for a future definitive trial of COB-MS, with respect to both feasibility and preliminary, clinical efficacy. In the event that results indicate efficacy, study findings will suggest that COB-MS requires consideration as a means of enhancing cognitive and daily functioning in people living with MS. Trial registration ISRCTN: ISRCTN11462710 . Registered on 9 September 2019.

Background. A recent survey of 109 healthcare professionals explored how UK healthcare professionals typically assess and treat multiple sclerosis (MS)-related cognitive impairment. Little is currently known about what constitutes usual care for cognitive impairment and psychosocial care for people with MS in Ireland. Aim. The aim of the current research was to survey healthcare professionals (HCPs) who work with people with MS, to understand current assessment and management of cognition and psychosocial care in people with MS in the Republic of Ireland. Methods. A cross-sectional survey design was used. Data were collected online through Microsoft forms and through postal responses. The original UK questionnaire was adapted, piloted, and distributed to Irish HCPs. Participants were qualified HCPs who work clinically with people with MS in the Republic of Ireland. Results. Ninety-eight HCPs completed the survey. Only 34% of those surveyed reported routine screening of cognition for people with MS within their services; approximately, 36% HCPs reported that they did not provide information or services in relation to cognition to people with MS and 39% reported not referring elsewhere when cognitive difficulties were suspected. Out of the 98 HCPs, 47% reported assessing mood difficulties as part of their services, with 14% unsure. In total, 70% of participants reported onward referral took place if mood difficulties were identified. The Montreal Cognitive Assessment was the most commonly administrated cognitive assessment. Cognitive intervention choices were found to be guided by clinical judgement in 75.5% of cases. Discussion. Despite the high importance placed on cognitive and psychosocial care, there is very little consistency in treatment and assessment across services for people with MS in Ireland.

In this Open Letter we present reflections from three different perspectives on the integration of public and patient involvement (PPI) in a research trial. We reflect on the experience of having a patient employed as a contract researcher, with no prior research experience, on a feasibility trial of cognitive rehabilitation in multiple sclerosis. This Open Letter is written by the PPI research team member with reflections from a researcher on the trial and the principal investigator. We will discuss some of the changes made and the impacts that have been resulted from of PPI input into the trial. We focus on PPI involvement in participant recruitment, the development of trial material, integration of PPI along the research cycle, and collaboration. We hope that this Open Letter will encourage principal investigators and groups to include PPI members as part of the research team and help patients and members of the public understand what the experience of PPI members is like.

The quantum approximate optimization algorithm (QAOA) transforms a simple many-qubit wave function into one that encodes a solution to a difficult classical optimization problem. It does this by optimizing the schedule according to which two unitary operators are alternately applied to the qubits. In this paper, the QAOA is modified by updating the operators themselves to include local fields, using information from the measured wave function at the end of one iteration step to improve the operators at later steps. It is shown by numerical simulation on MaxCut problems that, for a fixed accuracy, this procedure decreases the runtime of QAOA very substantially. This improvement appears to increase with the problem size. Our method requires essentially the same number of quantum gates per optimization step as the standard QAOA, and no additional measurements. This modified algorithm enhances the prospects for quantum advantage for certain optimization problems.

We propose a method to speed up the quantum adiabatic algorithm using catalysis by many-body delocalization. This is applied to random-field antiferromagnetic Ising spin models. The algorithm is catalyzed in such a way that the evolution approximates a Heisenberg model in the middle of its course, and the model is in a delocalized phase. We show numerically that we can speed up the standard algorithm for finding the ground state of the random-field Ising model using this idea. We also demonstrate that the speedup is due to gap amplification, even though the underlying model is not frustration-free. The crossover to speedup occurs at roughly the value of the interaction which is known to be the critical one for the delocalization transition. We also calculate the participation ratio and entanglement entropy as a function of time: Their time dependencies indicate that the system is exploring more states and that they are more entangled than when there is no catalyst. Together, all these pieces of evidence demonstrate that the speedup is related to delocalization. Even though only relatively small systems can be investigated, the evidence suggests that the scaling of the method with system size is favorable. Our method is illustrated by experimental results from a small online IBM quantum computer, showing how to verify the method in future as such machines improve. The cost of the catalytic method compared with the standard algorithm is only a constant factor.