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For solid-state spin qubits, single-gate rf readout can minimize the number of gates required for scale-up since the readout sensor can integrate into the existing gates used to manipulate the qubits. However, state-of-the-art topological error correction codes benefit from the ability to resolve the qubit state within a single shot, that is, without repeated measurements. Here, we demonstrate single-gate, single-shot readout of a singlet-triplet spin state in silicon, with an average readout fidelity of 82.9% at 3.3 kHz measurement bandwidth. We use this technique to measure a tripletT−to singletS0relaxation time of 0.62 ms in precision donor quantum dots in silicon. We also show that the use of rf readout does not impact the spin lifetimes (S0toT−decay remained approximately 2 ms at zero detuning). This establishes single-gate sensing as a viable readout method for spin qubits.

Aims/hypothesis Patient-reported outcome measures (PROMs) are increasingly used as key performance indicators in chronic illness. We sought to review the value of these tools in assessing health-related quality of life (HRQOL) in patients with diabetes-related foot disease and identify the impact of each foot problem on life quality. Methods A systematic review of literature on HRQOL PROMs in diabetes-related foot disease was performed according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. The quality of eligible studies was evaluated within pre-existing criteria. Results 53 studies written between 1995 and 2010 met the inclusion criteria. A variety of HRQOL PROMs were used. Disease-specific tools were better than generic at quantifying temporal changes in life quality and showed greater sensitivity to ulcer/neuropathic severity. No studies have simultaneously evaluated disease-specific tools. Generic and utility HRQOL PROMs are frequently used as secondary outcome measures in randomised trials and cost–utility analysis. HRQOL is depressed in diabetes, further impaired by the presence of foot disease. Ulcer healing is associated with improvements in HRQOL. Patients with active ulceration report poorer HRQOL than those whom have undergone successful minor lower extremity amputation (LEA) but there is a paucity of quality data on HRQOL outcomes for diabetes-related LEA. Conclusions/interpretation No one PROM was identified as a ‘gold standard’ for assessing HRQOL in diabetes-related foot disease. Specific areas for further development include the most valid HRQOL PROM with disease-specific content; HRQOL outcomes in minor and major amputations and the role of HRQOL tools in routine clinical care.

The effect of traumatic spinal cord injury (TSCI) on spinal cord blood flow (SCBF) in humans is unknown. Whether intervention to achieve the recommended mean arterial pressure (MAP) guideline of 85–90 mm Hg improves SCBF is also unclear. Here, we use laser speckle contrast imaging intraoperatively to visualize blood flow at the injury site in 22 patients with acute, severe spinal cord injuries (American Spinal Injuries Association Impairment Scale, grades A–C). In 17 of 22 patients, injury-site metabolism was also monitored with a microdialysis catheter placed intradurally on the surface of the injured cord. We observed three different SCBF patterns, characterized by distinct injury-site metabolic signatures, which we term necrosis-penumbra, hyperperfusion, and patchy-perfusion. The necrosis-penumbra pattern, only observed in thoracic injuries, had a core of low blood flow (necrosis) with regions of intermediate blood flow on either side (penumbra). The hyperperfusion pattern, only observed in cervical injuries, had very high blood flow throughout the injury site. The patchy-perfusion pattern, found in cervical and thoracic injuries, had irregular regions of low, intermediate, and high blood flow. Though intervention to increase MAP by 20 mm Hg increased overall blood flow at the injury site, in 5 of 22 patients, blood flow increased in some regions, but, surprisingly, decreased in other regions. We term this phenomenon blood pressure–induced local steal. In 7 of 19 patients with MAP 85–90 mm Hg, parts of the injury site were only perfused in systole, but not in diastole, which we term diastolic ischemia. We conclude that acute, severe TSCI produces three pathological blood flow patterns at the injury site. Intervention to increase blood pressure may elicit potentially detrimental SCBF responses in some patients.

Rapid, high-fidelity single-shot readout of quantum states is a ubiquitous requirement in quantum information technologies. For emitters with a spin-preserving optical transition, spin readout can be achieved by driving the transition with a laser and detecting the emitted photons. The speed and fidelity of this approach is typically limited by low photon collection rates and measurement back-action. Here we use an open microcavity to enhance the optical readout signal from a semiconductor quantum dot spin state, largely overcoming these limitations. We achieve single-shot readout of an electron spin in only 3 nanoseconds with a fidelity of (95.2 ± 0.7)%, and observe quantum jumps using repeated single-shot measurements. Owing to the speed of our readout, errors resulting from measurement-induced back-action have minimal impact. Our work reduces the spin readout-time well below both the achievable spin relaxation and dephasing times in semiconductor quantum dots, opening up new possibilities for their use in quantum technologies. Single-shot readout of optically active spin qubits is typically limited by low photon collection rates and measurement back-action. Here the authors overcome these limitations by using an open cavity approach for single-shot readout of a semiconductor quantum dot and demonstrate record readout time of a few ns.

Low mobility during hospitalization remains prevalent despite associated negative consequences. The goal of this quality improvement (QI) project was to increase patient mobility and function by adding a physical therapist (PT) to an existing interprofessional care team. A mobility technician assisted treatment group patients with mobility during hospitalization based on physical therapist recommendations. Change in functional status and highest level of mobility achieved by treatment group patients was measured from admission to discharge. Observed hospital length of stay (LOS), LOS index, and 30-day all cause hospital readmission comparisons between treatment group and a comparison group on the same unit, and between cross-sectional comparison groups one year prior were used for Difference in Difference analysis. Bivariate comparisons between the treatment and a cross-sectional comparison group from one year prior showed a statistically significant change in LOS Index. No other bivariate comparisons were statistically significant. Difference in Difference methods showed no statistically significant change in observed LOS, LOS Index, or 30-day readmission. Patients in the treatment group had statistically significant improvements in functional status and highest level of mobility achieved. Physical function and mobility improved for patients who participated in mobility sessions. Mobility technicians may contribute to improved care quality and patient safety in the hospital.

In some centers, monitoring lumbar cerebrospinal fluid (CSF) is used to guide management of patients with acute traumatic spinal cord injuries (TSCI) and draining lumbar CSF to improve spinal cord perfusion. Here, we investigate whether the lumbar CSF provides accurate information about the injury site and the effect of draining lumbar CSF on injury site perfusion. In 13 TSCI patients, we simultaneously monitored lumbar CSF pressure (CSFP) and intraspinal pressure (ISP) from the injury site. Using CSFP or ISP, we computed spinal cord perfusion pressure (SCPP), vascular pressure reactivity index (sPRx) and optimum SCPP (SCPPopt). We also assessed the effect on ISP of draining 10 mL CSF. Metabolites at the injury site were compared with metabolites in the lumbar CSF. We found that ISP was pulsatile, but CSFP had low pulse pressure and was non-pulsatile 21% of the time. There was weak or no correlation between CSFP versus ISP (R = -0.11), SCPP(csf) versus SCPP(ISP) (R = 0.39), and sPRx(csf) versus sPRx (ISP) (R = 0.45). CSF drainage caused no significant change in ISP in 7/12 patients and a significant drop of <5 mm Hg in 4/12 patients and of ∼8 mm Hg in 1/12 patients. Metabolite concentrations in the CSF versus the injury site did not correlate for lactate (R = 0.00), pyruvate (R = -0.12) or lactate-to-pyruvate ratio (R = -0.05) with weak correlations noted for glucose (R = 0.31), glutamate (R = 0.61), and glycerol (R = 0.56). We conclude that, after a severe TSCI, monitoring from the lumbar CSF provides only limited information about the injury site and that lumbar CSF drainage does not effectively reduce ISP in most patients.

Background Hospitalizations are a resource-intensive form of healthcare use, particularly for persons with chronic conditions such as HIV. In standardized Canadian hospitalization databases, it can be unclear whether a hospitalization record is an independent hospitalization, a planned interhospital transfer, or an unplanned readmission. Misclassifying hospitalization records can bias metrics (e.g., counting transfers as readmissions can inflate readmission counts) and hence yield incorrect results. We compared definitions for combining sequential, related hospitalization records to create hospitalization episodes of care (HEoC) within a cohort of persons with and without HIV (PWH; PWoH) in British Columbia (BC), Canada. Methods Acute care hospitalization records (April 1992 to March 2020) were sourced from the Discharge Abstract Database within the Comparative Outcomes And Service Utilization Trends (COAST) study, a BC data linkage that includes samples of PWH and PWoH. Guided by published approaches and data quality considerations, we compared eight HEoC definitions applied to PWH and PWoH. Definitions varied by the date gap between records (0 day [same-day] or ≤ 1 day), and transfer indication (none required, populated transfer fields, one-way matching of hospital transfer identifiers, or two-way matching of hospital transfer identifiers). Comparisons were primarily informed by the percentage of multi-record HEoCs (HEoCs involving multiple hospitalization records, including interhospital transfers), and feasibility given data quality. Results The sample included 56,455 hospitalization records from 10,826 PWH, and 973,430 hospitalization records from 299,053 PWoH. Across the eight HEoC definitions, the percentage of multi-record HEoCs varied from 2.8 to 6.0% among PWH and 3.6 to 5.5% among PWoH. Definitions yielding the highest percentage of multi-record HEoCs combined records without requiring a transfer indication; definitions yielding the lowest percentage of multi-record HEoCs required two-way agreement of hospital identifiers. Patterns were generally comparable among PWH and PWoH, and similar in sensitivity analyses. Conclusions Various approaches can be used to define HEoCs. We recommended a balanced HEoC definition – requiring at least one populated hospital identifier field (without requiring matching of hospital identifiers) and ≤ 1 day gap between each hospitalization record for general use purposes in HIV research. Future work may examine these definitions in other settings and populations.

Increasing global demand for copper (Cu) related to the energy transition requires that we understand the mechanisms by which Cu is enriched in the upper crust via magmatism. Porphyry Cu deposits (PCDs) are associated with arc volcanic systems and form under rare circumstances by precipitation from Cu-rich magmatic fluids. Here we develop models to delineate the magmatic conditions under which the Cu concentration and flux may be maximised in exsolved hydrous magmatic fluids. We show that ubiquitous sulfide saturation is a critical limitation on the Cu and sulfur load of exsolved magmatic fluids, owing to the strong partitioning of Cu into sulfide. Sulfide saturation in arc magmas may usually only be avoided under the most hydrous or oxidised conditions, which the global volcanic rock record suggests is not commonplace. However, thermally mature arc crust is likely to develop deep crustal cumulate zones in which sulfides may accumulate over time. When sulfide-undersaturated water-rich mafic melts percolate through these zones they may resorb sulfides during reactive flow. On volatile saturation, Cu-rich fluids will be generated that are viable precursors to PCDs.

Chronic Obstructive Pulmonary Disease (COPD) is associated with an increased risk of myocardial infarction and stroke but it remains unclear how to identify microvascular changes in this population. We hypothesized that simple non-mydriatic retinal photography is feasible and can be used to assess microvascular damage in COPD. Novel Vascular Manifestations of COPD was a prospective study comparing smokers with and without COPD, matched for age. Non-mydriatic, retinal fundus photographs were assessed using semi-automated software. Retinal images from 24 COPD and 22 control participants were compared. Cases were of similar age to controls (65.2 vs. 63.1 years, p = 0.38), had significantly lower Forced Expiratory Volume in one second (FEV1) (53.4 vs 100.1% predicted; p < 0.001) and smoked more than controls (41.7 vs. 29.6 pack years; p = 0.04). COPD participants had wider mean arteriolar (155.6 ±15 uM vs. controls [142.2 ± 12 uM]; p = 0.002) and venular diameters (216.8 ±20.7 uM vs. [201.3± 19.1 uM]; p = 0.012). Differences in retinal vessel caliber were independent of confounders, odds ratios (OR) = 1.08 (95% confidence intervals [CI] = 1.02, 1.13; p = 0.007) and OR = 1.05 (CI = 1.01, 1.09; p = 0.011) per uM increase in arteriolar and venular diameter respectively. FEV1 remained significantly associated with retinal vessel dilatation r = -0.39 (p = 0.02). Non-mydriatic retinal imaging is easily facilitated. We found significant arteriole and venous dilation in COPD compared to age-matched smokers without COPD associated with lung function independent of standard cardiovascular risk factors. Retinal microvascular changes are known to be strongly associated with future vascular events and retinal photography offers potential to identify this risk. clinicaltrials.gov NCT02060292.

In five patients with acute, severe thoracic traumatic spinal cord injuries (TSCIs), American spinal injuries association Impairment Scale (AIS) grades A–C, we induced cord hypothermia (33 °C) then rewarming (37 °C). A pressure probe and a microdialysis catheter were placed intradurally at the injury site to monitor intraspinal pressure (ISP), spinal cord perfusion pressure (SCPP), tissue metabolism and inflammation. Cord hypothermia–rewarming, applied to awake patients, did not cause discomfort or neurological deterioration. Cooling did not affect cord physiology (ISP, SCPP), but markedly altered cord metabolism (increased glucose, lactate, lactate/pyruvate ratio (LPR), glutamate; decreased glycerol) and markedly reduced cord inflammation (reduced IL1β, IL8, MCP, MIP1α, MIP1β). Compared with pre-cooling baseline, rewarming was associated with significantly worse cord physiology (increased ICP, decreased SCPP), cord metabolism (increased lactate, LPR; decreased glucose, glycerol) and cord inflammation (increased IL1β, IL8, IL4, IL10, MCP, MIP1α). The study was terminated because three patients developed delayed wound infections. At 18-months, two patients improved and three stayed the same. We conclude that, after TSCI, hypothermia is potentially beneficial by reducing cord inflammation, though after rewarming these benefits are lost due to increases in cord swelling, ischemia and inflammation. We thus urge caution when using hypothermia–rewarming therapeutically in TSCI.