Probing single electrons across 300-mm spin qubit wafers.

Building a fault-tolerant quantum computer will require vast numbers of physical qubits. For qubit technologies based on solid-state electronic devices1-3, integrating millions of qubits in a single processor will require device fabrication to reach a scale comparable to that of the modern complementary metal-oxide-semiconductor (CMOS) industry. Equally important, the scale of cryogenic device testing must keep pace to enable efficient device screening and to improve statistical metrics such as qubit yield and voltage variation. Spin qubits1,4,5 based on electrons in Si have shown impressive control fidelities6-9 but have historically been challenged by yield and process variation10-12. Here we present a testing process using a cryogenic 300-mm wafer prober13 to collect high-volume data on the performance of hundreds of industry-manufactured spin qubit devices at 1.6 K. This testing method provides fast feedback to enable optimization of the CMOS-compatible fabrication process, leading to high yield and low process variation. Using this system, we automate measurements of the operating point of spin qubits and investigate the transitions of single electrons across full wafers. We analyse the random variation in single-electron operating voltages and find that the optimized fabrication process leads to low levels of disorder at the 300-mm scale. Together, these results demonstrate the advances that can be achieved through the application of CMOS-industry techniques to the fabrication and measurement of spin qubit devices.

Evaluating a brief online compassion-focused intervention for intensive care nurses.

BACKGROUND: High levels of stress have been found within health care staff, particularly in the nursing population, which is somewhat attributed to the Covid-19 pandemic. The development of self-compassion, a protective psychological construct, may promote well-being in the health care staff population. As part of a service development project, the authors delivered and evaluated a brief online compassion-focused intervention with nurses working within Intensive Care Units (ICUs). AIMS: Aims were to explore feasibility within the ICU nursing population and consider potential benefits to psychological well-being. METHODS: ICU nurses registered for an online, 4 week, compassion-focused intervention as part of a service development project. Measures of compassion, burnout, trauma, and the emotional climate of their work environment were analysed in two groups; those who completed the intervention and those who did not. Baseline and post-intervention measures were analysed to infer the potential benefits of the intervention. RESULTS: Compared with their baseline scores, those who completed the intervention showed improvements on measures of compassion, soothing in emotional climate, and reductions in burnout, trauma and threat in emotional climate. At baseline, those who did not complete the intervention scored lower on measures of compassion and soothing within their emotional climate, as well as higher levels of trauma and threat within the emotional climate, compared with those who engaged with the intervention. CONCLUSIONS: Brief online compassion-focused interventions may be a useful platform to promote well-being in ICU nurses, but possibly only for those who have a pre-established level of self-compassion.

How Valley-Orbit States in Silicon Quantum Dots Probe Quantum Well Interfaces.

The energies of valley-orbit states in silicon quantum dots are determined by an as yet poorly understood interplay between interface roughness, orbital confinement, and electron interactions. Here, we report measurements of one- and two-electron valley-orbit state energies as the dot potential is modified by changing gate voltages, and we calculate these same energies using full configuration interaction calculations. The results enable an understanding of the interplay between the physical contributions and enable a new probe of the quantum well interface.

Coherent Control and Spectroscopy of a Semiconductor Quantum Dot Wigner Molecule.

Semiconductor quantum dots containing more than one electron have found wide application in qubits, where they enable readout and enhance polarizability. However, coherent control in such dots has typically been restricted to only the lowest two levels, and such control in the strongly interacting regime has not been realized. Here we report quantum control of eight different transitions in a silicon-based quantum dot. We use qubit readout to perform spectroscopy, revealing a dense set of energy levels with characteristic spacing far smaller than the single-particle energy. By comparing with full configuration interaction calculations, we argue that the dense set of levels arises from Wigner-molecule physics.

Neuropsychiatric Lupus with Antibody-Mediated Striatal Encephalitis.

Systemic lupus erythematosus is a chronic autoimmune disease characterized by the production of autoantibodies resulting in tissue injury across multiple organs; up to 50% of patients develop neurologic involvement, collectively referred to as neuropsychiatric systemic lupus erythematosus. The cases in this clinical report will highlight a subtype of neuropsychiatric systemic lupus erythematosus demonstrating imaging findings of striatal inflammation responsive to plasmapheresis similar to those in the subset of N-methyl-D-aspartate receptor autoimmune encephalitis that involves the striatum. Although the cause for this striking imaging appearance is not definitely known, literature will be presented supporting the hypothesis that it is due to peripheral anti-double-stranded DNA antibodies entering the central nervous system to cross-react with N-methyl-D-aspartate receptor antigens.

TRPV1 antagonists that cause hypothermia, instead of hyperthermia, in rodents: Compounds' pharmacological profiles, in vivo targets, thermoeffectors recruited and implications for drug development.

AIM: Thermoregulatory side effects hinder the development of transient receptor potential vanilloid-1 (TRPV1) antagonists as new painkillers. While many antagonists cause hyperthermia, a well-studied effect, some cause hypothermia. The mechanisms of this hypothermia are unknown and were studied herein. METHODS: Two hypothermia-inducing TRPV1 antagonists, the newly synthesized A-1165901 and the known AMG7905, were used in physiological experiments in rats and mice. Their pharmacological profiles against rat TRPV1 were studied in vitro. RESULTS: Administered peripherally, A-1165901 caused hypothermia in rats by either triggering tail-skin vasodilation (at thermoneutrality) or inhibiting thermogenesis (in the cold). A-1165901-induced hypothermia did not occur in rats with desensitized (by an intraperitoneal dose of the TRPV1 agonist resiniferatoxin) sensory abdominal nerves. The hypothermic responses to A-1165901 and AMG7905 (administered intragastrically or intraperitoneally) were absent in Trpv1-/- mice, even though both compounds evoked pronounced hypothermia in Trpv1+/+ mice. In vitro, both A-1165901 and AMG7905 potently potentiated TRPV1 activation by protons, while potently blocking channel activation by capsaicin. CONCLUSION: TRPV1 antagonists cause hypothermia by an on-target action: on TRPV1 channels on abdominal sensory nerves. These channels are tonically activated by protons and drive the reflectory inhibition of thermogenesis and tail-skin vasoconstriction. Those TRPV1 antagonists that cause hypothermia further inhibit these cold defences, thus decreasing body temperature. SIGNIFICANCE: TRPV1 antagonists (of capsaicin activation) are highly unusual in that they can cause both hyper- and hypothermia by modulating the same mechanism. For drug development, this means that both side effects can be dealt with simultaneously, by minimizing these compounds' interference with TRPV1 activation by protons.

Autoimmune Encephalitis: Pathophysiology and Imaging Review of an Overlooked Diagnosis.

Autoimmune encephalitis is a relatively new category of immune-mediated disease involving the central nervous system that demonstrates a widely variable spectrum of clinical presentations, ranging from the relatively mild or insidious onset of cognitive impairment to more complex forms of encephalopathy with refractory seizure. Due to its diverse clinical features, which can mimic a variety of other pathologic processes, autoimmune encephalitis presents a diagnostic challenge to clinicians. Imaging findings in patients with these disorders can also be quite variable, but recognizing characteristic findings within limbic structures suggestive of autoimmune encephalitis can be a key step in alerting clinicians to the potential diagnosis and ensuring a prompt and appropriate clinical work-up. In this article, we review antibody-mediated encephalitis and its various subtypes with a specific emphasis on the role of neuroimaging in the diagnostic work-up.

Coinage metal coordination chemistry of stable primary, secondary and tertiary ferrocenylethyl-based phosphines.

Ferrocene-based phosphines constitute an important auxiliary ligand in inorganic chemistry. Utilizing the (ferrocenylethyl)phosphines (FcCH2CH2)3-nHnP (Fc = ferrocenyl; n = 2, 1; n = 1, 2; n = 0, 3) the synthesis of a series of coordination complexes [(FcCH2CH2)3-nHnPCuCl]4 (n = 2, 1-CuCl; n = 0, 3-CuCl), [(FcCH2CH2)2HPCuCl] (2-CuCl), {[(FcCH2CH2)H2P]2AgCl}2 (1-AgCl), [(FcCH2CH2)2HPAgCl] (2-AgCl), [(FcCH2CH2)3PAgCl]4 (3-AgCl), [(FcCH2CH2)3PM(OAc)]4 (M = Cu, 3-CuOAc M = Ag, 3-AgOAc), [(FcCH2CH2)3-nHnPAuCl] (n = 1, 2-AuCl; n = 0, 3-AuCl), via the reaction between the free phosphine and MX (M = Cu, Ag and Au; X = Cl, OAc), is described. The reaction between the respective phosphine with a suspension of metal-chloride or -acetate in a 1 : 1 ratio in THF at ambient temperature affords coordinated phosphine-coinage metal complexes. Varying structural motifs are observed in the solid state, as determined via single crystal X-ray analysis of 1-CuCl, 3-CuCl, 1-AgCl, 3-AgCl, 3-CuOAc, 3-AgOAc, 2-AuCl and 3-AuCl. Complexes 1-CuCl and 3-CuCl are tetrameric Cu(i) cubane-like structures with a Cu4Cl4 core, whereas silver complexes with primary and tertiary phosphine reveal two different structural types. The structure of 1-AgCl, unlike the rest, displays the coordination of two phosphines to each silver atom and shows a quadrangle defined by two Ag and two Cl atoms. In contrast, 3-AgCl is distorted from a cubane structure via elongation of one of the ClAg distances. 3-CuOAc and 3-AgOAc are isostructural with step-like cores, while complexes 2-AuCl and 3-AuCl reveal a linear geometry of a phosphine gold(i) chloride devoid of any aurophilic interactions. All of the complexes were characterized in solution by multinuclear (1)H, (13)C{(1)H} and (31)P NMR spectroscopic techniques; the redox chemistry of the series of complexes was examined using cyclic voltammetry. This class of complexes has been found to exhibit one reversible Fe(ii)/Fe(iii) oxidation couple, suggesting the absence of electronic communication between the ferrocenyl units on individual phosphine ligands as well as between different phosphines on the polymetallic cores.

Substance abuse and criminal activities following traumatic brain injury in childhood, adolescence, and early adulthood.

OBJECTIVE: Use a longitudinal birth cohort to evaluate the association of traumatic brain injury at ages 0 to 5, 6 to 15, and 16 to 21 years with drug and alcohol abuse and engagement in criminal activities. MAIN MEASURES: Follow-up over 21 to 25 years using self-report of drug and alcohol use, arrests, and violent and property offenses. Outcomes were assessed for 2 levels of severity (inpatient, hospitalized; outpatient, seen by general practitioner or at emergency department). PARTICIPANTS: Members of the Christchurch Health and Development Study, a longitudinal birth cohort. SETTING: Christchurch, New Zealand. RESULTS: Adjusted for child and family factors, compared with noninjured individuals, inpatients injured at 0 to 5 years or 16 to 21 years were more likely to have symptoms consistent with drug dependence. All inpatient groups had increased risk of arrest, with the age groups of 0 to 5 and 6 to 15 years more likely to be involved in violent offenses and the age group of 0 to 5 years more likely to engage in property offenses. Outpatient group had an increased risk of violent offenses for first injury 0 to 5 years, arrests and property offenses for injury 6 to 15 years, and increased risk of arrests and violent offenses for injury 16 to 21 years of age. However, when alcohol dependence and drug dependence were added as an additional covariate, traumatic brain injury was no longer associated with criminal behavior for the age group of 0 to 5 years. CONCLUSIONS: Traumatic brain injury is associated with increased criminal behavior and may represent a risk factor for offending. However, early substance use is a mediating factor for those injured early in life.

Health care quality in the 21st century.

The concepts of healthcare quality have evolved over the years. Many stakeholders have become quite engaged in the movement towards improvement in healthcare quality and safety. The standardization and national endorsement of performance measures, the assessment of outcomes, and the reporting for accountability are now being coupled with more transparency, and technological innovation. As the quality landscape changes to evaluation of episodes of care and performance at the individual clinician level measures (primary and specialty care), collaboration is critical among consumers, purchasers, measure developers, implementers of measures to identify and adopt national standards to tell a clear story of healthcare quality.

Domains of a TBI minimal data set: community reintegration phase.

Efforts to establish a minimal data set for the period of community integration after traumatic brain injury (TBI) have been the focus of a working group of leading researchers, clinicians and advocates attending the Galveston Brain Injury Symposium in 2001 and 2002. The purpose of the data set is to increase the consistency and interpretability of TBI research and programme evaluation by providing a common set of measures to document key aspects of community integration. It is intended to be sensitive to intervention, comprehensive, reflect satisfaction and outcome and promote future treatment/therapy. In deciding on the components of a minimal data set, the tri-partite model of outcomes was adopted (initially employed in psychotherapy, adapted to TBI) which focuses on the needs of the individual, society and the health provider. Scales are recommended for the respective components of the model.

Deep vein thrombosis in a tiler wearing tight knee pads.

Venous compression is a rare but accepted cause of Deep Venous Thrombosis. We report a case of DVT caused by extrinsic compression of the popliteal vein by constricting elasticated knee pads. The knee pads were worn at work by a Tiler who did not have any hypercoagulability disorder.

Treatment of chronic haemophilic synovitis in humans with D-penicillamine.

Chronic proliferative synovitis secondary to haemathroses is a major complication in patients with severe haemophilia. Current management strategies include prophylactic infusions of the missing coagulation factor, corticosteroids, synoviorthesis and/or synovectomy with variable degrees of benefit. In addition, patients with coagulation factor inhibitors are not amenable to the invasive therapeutic modalities. The gross and microscopic findings of the synovitis in haemophilic arthritis are remarkably similar to those seen in patients with rheumatoid arthritis, although the pathophysiology of these two conditions are quite different. Haemophilic arthropathy, in the later stages, resembles degenerative rather than inflammatory joint disease. Oral D-penicillamine, a drug effective in the proliferative synovitis of rheumatoid arthritis, was evaluated in 16 patients. Ten patients had an unequivocal response, while three had a reduction in palpable synovium and three had no response. Thus 81% of the patients had a beneficial response. Minor reversible drug side-effects occurred in two patients (proteinuria in one and a rash in the second). The results of this study suggest that D-penicillamine is an effective and safe drug for the treatment of haemophilic chronic synovitis.

Outcome of calcaneal fractures treated operatively and non-operatively. the effect of litigation on outcomes.

BACKGROUND: The optimum management of calcaneal fractures is controversial. These injuries are frequently associated with compensation litigation, which effects the outcome. AIMS: To assess the outcome of operatively and conservatively managed intra-articular calcaneal fractures and to examine the effect of compensation litigation on outcome. METHODS: This was a retrospective study of calcaneal fractures from a single regional trauma unit, with management decided by the admitting consultant surgeon's preference. Fifty-four patients (33 operative, 21 conservative) with an average follow-up of 40 months (range 14-78 months) were reviewed. Sixteen patients (30%) were pursuing a compensation case resulting from the injury. RESULTS: Despite similar fractures, medical co-morbidity and trauma energy, significantly worse outcome scores were seen in litigants (p < 0.0001). Footwear fitting problems were greater in litigants. Time off work was more than twice that of non-litigants (14.5 vs 6 months, p < 0.01). Results were similar between the operative and non-operative groups in terms of functional score, footwear problems and time off work. CONCLUSIONS: Litigation was the major determinant of outcome following calcaneal fracture repair; highlighting the unreliability of subjective evaluation in determining outcome in the face of litigation. No subset of patients appeared to significantly benefit from internal fixation of their fracture.

Life satisfaction after traumatic brain injury.

OBJECTIVE: To investigate correlates of life satisfaction after traumatic brain injury (TBI). DESIGN: Prospective, longitudinal study of patients with TBI studied 1 and 2 years after injury. SETTING: A specialized inpatient TBI rehabilitation unit in a midwestern academic medical center. SUBJECTS: Two hundred eighteen consecutive patients admitted for rehabilitation, at least 14 years of age, with a primary diagnosis of TBI, consented to participate, and interviewed 1 and/or 2 years after injury (112 interviewed both years, 58 at year 1 only, 48 at year 2 only). MAIN OUTCOME MEASURES: Satisfaction With Life Scale. RESULTS: Stepwise multiple regressions accounted for statistically significant, but small, proportions of variance. Not having a preinjury history of substance abuse and having gainful employment at the time of follow-up were associated with higher life satisfaction both 1 and 2 years after injury. Motor independence at rehabilitation discharge was also associated at 1 year. Current social integration and the absence of depressed mood were associated at 2 years. Life satisfaction was relatively stable between years. Change that did occur was associated with marital status and depressed mood 2 years after injury. CONCLUSIONS: Life satisfaction after TBI seems to be related to attaining healthy and productive lifestyles. Future research should investigate other factors that affect life satisfaction to increase prediction and appreciate all influences on subjective well being after TBI.

Hemolytic-uremic syndrome.

The hemolytic-uremic syndrome (HUS) has been recognized for more than 45 years and consists of the combination of hemolytic anemia, thrombocytopenia, and acute renal failure. HUS occurs predominantly in children younger than 4 years of age. It is the most frequent cause of acute renal failure in children. The most common form of the syndrome (D+ HUS) occurs in healthy young children (>6 mo to <5 y of age) and is preceded by watery diarrhea that can evolve to hemorrhagic colitis. The diarrhea precedes the hemolysis and thrombocytopenia by 5 to 7 days; oliguria/anuria follows several days later. Although the pathogenesis is unknown, available evidence strongly suggests that endothelial cell damage is necessary. The outcome for most patients who have D+ HUS is favorable: 65% to 85% recover completely, 5% to 10% die (usually during the acute illness), recurrence is uncommon, and only a few patients slowly progress to end-stage renal disease (ESRD).

Janet Corrigan on the Institute of Medicine and Healthcare Quality. Interview by Wanda Bishop and Luc R. Pelletier.

Janet Corrigan, PhD MBA, is director of the Board on Health Care Services and director of the Quality of Health Care in America Project at the Institute of Medicine (IOM) in Washington, DC. The Board on Health Care Services is the component of the IOM that is responsible for projects involving healthcare delivery, financing, benefits coverage, the uninsured, and quality of care. Before her work with IOM, she was executive director of the President's Advisory Commission on Consumer Protection and Quality in the Health Care Industry. Dr. Corrigan's work has been concentrated in the areas of quality of care, with particular emphasis on quality measurement, improvement, and reporting for accountability. She received her doctorate in health services organization and policy and a master's degree in industrial engineering from the University of Michigan. She also holds master's degrees in business administration and in community health from the University of Rochester.

Role of agitation in prediction of outcomes after traumatic brain injury.

OBJECTIVE: To determine the role of agitation in the prediction of traumatic brain injury rehabilitation outcomes. DESIGN: A longitudinal study of 340 consecutive patients admitted to an acute traumatic brain injury rehabilitation unit was conducted. Outcomes under study included rehabilitation length of stay, discharge destination, functional independence at discharge (FIM instrument), productivity at 1-yr follow-up, and life satisfaction at 1-yr follow-up (Satisfaction with Life Scale). RESULTS: Univariate analyses suggested that the presence of agitation in rehabilitation is predictive of a longer length of stay and decreased functional independence in the cognitive realm at discharge. In addition, individuals who exhibit agitation at any time during rehabilitation are less likely to be discharged to a private residence. However, multivariate analyses indicated that cognitive functioning at admission to rehabilitation (FIM cognitive) mediates the relationship between the presence of agitation and length of rehabilitation, as well as between agitation and FIM cognitive at discharge. Similar results were found when discharge residence was the dependent variable; however, agitation also contributed some unique variance to the prediction. Lower cognitive functioning at admission to rehabilitation was associated with the occurrence of agitation during rehabilitation, longer length of stay, lower cognitive functioning at discharge, and a decreased likelihood that an individual would be discharged to a private residence. CONCLUSIONS: The results of the multivariate analyses support the contention that agitation and cognition are intimately related, with the long-term effects of the former being at least partially driven by the latter. These findings support the importance of systematically monitoring both agitation and cognition when applying interventions to reduce agitation.

Trialkylphosphine-stabilized copper-phenyltellurolate complexes: from small molecules to nanoclusters via condensation reactions.

Reactions of CuCl with Te(Ph)SiMe3 and solublizing trialkylphosphine ligands afford a series of polynuclear copper-phenyltellurolate complexes that has been structurally characterized. The formation of the complexes is found to be highly dependent on the ancillary phosphine ligand used. The synthesis and structures of [Cu2(mu-TePh)2(PMe3)4] 1, [Cu4(mu3-TePh)4(PPr(i)3)3] 2, [Cu5(mu-TePh)3(mu3-TePh)3(PEt3)3][PEt3Ph] 3, and [Cu12Te3(mu3-TePh)6(PEt3)6] 4 are described. The telluride (Te(2-)) ligands in 4 arise from the generation of TePh2 in the reaction mixtures. The subsequent co-condensation of clusters 3 and 4 leads to the generation of the nanometer sized complex [Cu29Te9(mu3-TePh)10(mu4-TePh)2(PEt3)8][PEt3Ph] 5 in good yield, in addition to small amounts of [Cu39(mu3-TePh)10(mu4-TePh)Te16(PEt3)13] 6. These complexes are formed via the photo elimination of TePh2. The cyclic voltammogram of 5 in THF solution exhibits two oxidation waves, assigned to the oxidation of the Cu(I) centers.