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Abstract The diamond potential of kimberlites is difficult to assess due to several mantle and magmatic processes affecting diamond content. Traditionally, initial evaluations are based on the compositions of mantle-derived minerals (garnet, chromite, clinopyroxene), which allow an assessment of pressure-temperature conditions and lithologies suitable for diamond formation. Here we explore a complementary approach that considers the conditions of diamonds destruction by interaction with melts/fluids (metasomatism). We test the hypothesis that carbonate-rich metasomatism related to kimberlite melt infiltration into the deep lithosphere is detrimental to diamond preservation. Our results show that high diamond grades in kimberlites worldwide are exclusively associated with high-Mg/Fe olivine, which corresponds to mantle lithosphere minimally affected by kimberlite-related metasomatism. Diamond dissolution in strongly metasomatised lithosphere containing low-Mg/Fe olivine provides a causal link to the empirical associations between low diamond grades, abundant Ti-Zr-rich garnets and kimberlites with high Ti and low Mg contents. This finding show-cases olivine geochemistry as a viable tool in diamond exploration.

Background: Total knee arthroplasty (TKA) serves as a reliable treatment option for patients with end-stage arthritis, but patient dissatisfaction rate remains high. With the projected increase in the volume of arthroplasty operations, surgeons have aimed for methods in which to improve the patient outcomes. Robotic-assisted TKA has become increasingly popular. The learning curve for such technology has been investigated, but these prior studies have only been performed by fellowship-trained arthroplasty surgeons. The goal of this study was to investigate the learning curve for non-fellowship-trained orthopedic surgeons to ameliorate any concerns about increased operative time. Methods: Retrospective analysis of robotic-assisted TKAs and manual TKAs, performed by two non-fellowship-trained orthopedic surgeons, was conducted on a total of 160 patients. For each individual surgeon, the robotic-assisted TKAs were divided into 3 cohorts of 20 consecutive patients. Data from 20 consecutive manual TKAs were also gathered for each surgeon. The mean operative times were compared. Cohorts were then grouped together for both surgeons and compared in a similar fashion. Results: For surgeon 1, mean operative times were significantly increased for robotic-assisted cohorts compared with those for the manual cohort. For surgeon 2, the first robotic-assisted cohort was significantly longer. However, there were no significant differences for the second and third robotic-assisted cohorts. In the combined surgeon group, there was no significant difference between operative times for the third robotic cohort and the manual cohort. Conclusion: This study demonstrates that the general orthopedic surgeon in a community hospital may be able to adequately perform robotic-assisted surgery in a similar timeframe to their manual TKA within their first 40 robotic-arm-assisted TKA.

Abstract Background and Aims In recent years, Beijing, similar to many other large cities in China, has experienced rapid urbanization in many new areas. These have often been locations of population aging but have not had concomitant development of required community care services for older persons. This study aims to understand the perception and utilization of newly developed community care services by the older persons living in this region for providing knowledge to improve the services. Methods Applying Andersen's behavior model, this study used binary logistic regression of the factors influencing the perception and utilization of community care services and analyzed data collected by questionnaires to 301 older persons in the new urban areas of Beijing. Results Education, income, activities of daily living, instrumental activities of daily living, mental health, and economic needs are statistically significant factors affecting older persons' perception of community care services. Age, perception of community care services, income, neighborhood relationships, mental health, and emotional needs are significant factors affecting older persons' utilization of community care services. Conclusion Demographic characteristics, health status, social support, and care needs were significant factors in the perception and utilization of community care services, after controlling for many variables. Improving older persons' perceptions of community care services is likely to promote their access to the services, which should help meet the challenges of rapid population aging in providing community care services to support aging in place in the new urban areas of Beijing, China.

Abstract The modern western Pacific basins and arcs formed during the Cenozoic are considered to be underlain by Indian‐type asthenospheric mantle. Nevertheless, Mesozoic volcanic arcs are rare in the western Pacific, and as a result, the nature of the mantle source and subduction history in the western Pacific remains unclear. The Gagua Ridge constitutes the western boundary of the Philippine Sea Plate; however, its geologic nature and genesis are unclear. Here, we determine whole‐rock major and trace elements and Sr‐Nd‐Pb‐Hf‐Mg isotopic compositions and emplacement ages of the volcanic rocks from the Gagua Ridge. These rocks are classified as trachy‐andesites and basaltic andesites. They are characterized by depletion in Nb‐Ta and enrichment in large ion lithosphile elements, confirming their arc affinity. 40Ar‐39Ar analyses of plagioclase yields ages of 124‐123 Ma for the basaltic andesite group and ∼115 Ma for the trachy‐andesite group. The elevated Zr‐Hf‐K of these rocks coupled with high Th/La ratios indicate melting of subducted sediments. The anomalously high Nb/Ta (mean ∼33) can be explained by slab melting with residual rutile. These rocks also show the highest δ26Mg (−0.14 to 0.4‰) for arc lavas ever reported and the δ26Mg values are coupled with rare earth element compositions, which can be explained by interaction of sediment melts with altered peridotite/altered oceanic crust in the subduction zone. These volcanic rocks have Nd‐Hf isotopes similar to the Pacific mantle, indicating the presence of Pacific‐type mantle in the Early Cretaceous western Pacific.

Abstract Despite the scientific and economic significance of kimberlites and related magmas, their origin is unclear. Here, we address this issue using whole‐rock and perovskite‐derived Sr‐Nd‐Hf isotopes for the three occurrences of kimberlite, lamproites and ultramafic lamprophyres (UMLs) in Finland. Mesoproterozoic olivine lamproites at Lentiira‐Kuhmo and UMLs at Kuusamo have different isotopic signatures yet were emplaced contemporaneously at 1,200 Ma in response to an extensional regime linked to the Baltica‐Laurentia breakup. The low εNd(i) and εHf(i) values of the olivine lamproites are consistent with an enriched subcontinental lithospheric mantle (SCLM) source while UML compositions are intermediate between those of typical kimberlites and lamproites and are interpreted to reflect mixing of asthenospheric melts and ∼10%–15% of melts sourced from metasomatized SCLM. The ∼750 Ma Kuusamo kimberlites, are probably linked to the mantle plume activity that initiated Rodinia's break‐up, exhibiting homogenous isotopic compositions which mirror the prominent Geodynamic and Source Constraints for ∼1,200 Ma Olivine Lamproite and Ultramafic Lamprophyre Magmatism in Eastern Finland (PREMA)‐like signature of kimberlites globally. By contrast, ∼620–585 Ma Kaavi‐Kuopio kimberlites show limited range in εNd(i) and 87Sr/86Sr(i) but have remarkably heterogeneous εHf(i) (+6.5 to −6.3) with a temporal trend toward lower εHf(i) values. While the Kuusamo kimberlites erupted during the early stage of continental break‐up, the Kaavi‐Kuopio kimberlites were emplaced when Rodinia break‐up was completed, coeval with formation of the Central Iapetus large igneous province. Magmas forming the Kaavi‐Kupio kimberlites may have formed from an upwelling mantle source similar to PREMA modified by increasing incorporation (up to 10%) of recycled crustal material through time accounting for the trend toward lower εHf(i) in these kimberlites.

In nature, sensory and physical characteristics of the environment tend to match; for example, a surface that looks bumpy is bumpy. In human-built environments, they often don’t. Here, we report observations from people exploring if mismatch between visual and physical characteristics affected their perceived walking experience. Participants walked across four flat floors, each comprising of a visual illusion: two patterns perceived as alternating 3D “furrows and ridges,” the Primrose Field illusion, and a variant of the Cafe Wall illusion as a control pattern without perceived 3D effects. Participants found all patterns intriguing to look at; some describing them as “playful” or “gentle.” More than half found some of the patterns uncomfortable to walk on, aversive, affecting walking stability, and occasionally even evoking fear of falling. These experiences raise crucial research questions for the vision sciences into the impact of architectural design on well-being and walkability.

Summary: Rapid COVID-19 diagnosis in the hospital is essential, although this is complicated by 30%–50% of nose/throat swabs being negative by SARS-CoV-2 nucleic acid amplification testing (NAAT). Furthermore, the D614G spike mutant dominates the pandemic and it is unclear how serological tests designed to detect anti-spike antibodies perform against this variant. We assess the diagnostic accuracy of combined rapid antibody point of care (POC) and nucleic acid assays for suspected COVID-19 disease due to either wild-type or the D614G spike mutant SARS-CoV-2. The overall detection rate for COVID-19 is 79.2% (95% CI 57.8–92.9) by rapid NAAT alone. The combined point of care antibody test and rapid NAAT is not affected by D614G and results in very high sensitivity for COVID-19 diagnosis with very high specificity.

Summary: There is an urgent need for rapid SARS-CoV-2 testing in hospitals to limit nosocomial spread. We report an evaluation of point of care (POC) nucleic acid amplification testing (NAAT) in 149 participants with parallel combined nasal and throat swabbing for POC versus standard lab RT-PCR testing. Median time to result is 2.6 (IQR 2.3–4.8) versus 26.4 h (IQR 21.4–31.4, p < 0.001), with 32 (21.5%) positive and 117 (78.5%) negative. Cohen’s κ correlation between tests is 0.96 (95% CI 0.91–1.00). When comparing nearly 1,000 tests pre- and post-implementation, the median time to definitive bed placement from admission is 23.4 (8.6-41.9) versus 17.1 h (9.0–28.8), p = 0.02. Mean length of stay on COVID-19 “holding” wards is 58.5 versus 29.9 h (p < 0.001). POC testing increases isolation room availability, avoids bed closures, allows discharge to care homes, and expedites access to hospital procedures. POC testing could mitigate the impact of COVID-19 on hospital systems.

Abstract Background Chronic lymphocytic leukaemia (CLL) is the most common adult leukaemia. Achieving minimal residual disease (MRD) negativity in CLL is an independent predictor of survival even with a variety of different treatment approaches and regardless of the line of therapy. Methods/design GA101 (obinutuzumab) monocLonal Antibody as Consolidation Therapy In CLL (GALACTIC) is a seamless phase II/III, multi-centre, randomised, controlled, open, parallel-group trial for patients with CLL who have recently responded to chemotherapy. Participants will be randomised to receive either obinutuzumab (GA-101) consolidation or no treatment (as is standard). The phase II trial will assess safety and short-term efficacy in order to advise on continuation to a phase III trial. The primary objective for phase III is to assess the effect of consolidation therapy on progression-free survival (PFS). One hundred eighty-eight participants are planned to be recruited from forty research centres in the United Kingdom. Discussion There is evidence that achieving MRD eradication with alemtuzumab consolidation is associated with improvements in survival and time to progression. This trial will assess whether obinutuzumab is safe in a consolidation setting and effective at eradicating MRD and improving PFS. Trial registration ISRCTN, 64035629 . Registered on 12 January 2015. EudraCT, 2014-000880-42 . Registered on 12 November 2014.

Malignant tension hydrothorax is rare. Here we present a malignant tension hydrothorax secondary to small cell lung cancer (SCLC). To our knowledge, this is the first report of this entity. Briefly, a 53‐year‐old male smoker presented in acute distress after months of fatigue, shortness of breath, and weight loss. On examination his heart rate was 122, respiratory rate 31, blood pressure 102/60, oxygen saturation 92%, and he had tracheal deviation to the left with absent breath sounds on the right. Work‐up revealed hyponatraemia and a large pleural effusion causing tracheal deviation, mediastinal shift and compression of abdominal contents. There were associated masses in the right lung upper lobe and tail of the pancreas. Urgent, interval drainage of the effusion over several hours with tube thoracostomy relieved his symptoms while also avoiding life‐threatening re‐expansion pulmonary oedema. Subsequent thoracoscopic pleural biopsies revealed extensive SCLC. He was advised to begin urgent chemotherapy.

Background: In 2013, public health moved into Local Authorities, but initial optimism has been overtaken by serious ongoing financial constraints and an uncertain future. Hard choices have become an everyday reality across local authorities and for their public health teams. Assessing the return-on-investment of public health interventions and possessing economic evaluation skills have become more critical than ever before.Methods: Using the New Economy cost-benefits-analysis model developed at the Greater Manchester Combined Authority, we undertook cost benefit analyses of some of our largest areas of commissioned spend in local public health practice to better understand both the public and fiscal returns of our interventions.Results: The cost-benefit analyses indicated considerable variation in the public (economic and social) returns-on-investment for our spend on services purchased as a commissioner with £1.37 to 6.81 returned for every £1 spent, and a fiscal return for every £1 invested of between £0.54 and 1.37. Additionally, the fiscal benefits (reduced service costs) of these public health interventions appear to primarily flow to the NHS, which accounts for about 94% of the fiscal return.Conclusion: While cost-benefit modeling cannot provide a complete picture of “value,” it does provide decision-makers with a transparent metric that facilitates a whole-of system discussion on “intervention value” and prevention at scale investments. This approach will support investment strategies when implementing Sustainability and Transformation Partnerships and Integrated Care Systems. However, these tools should be used to support robust decision-making processes, not as a replacement for or a short-circuiting of existing processes.

We present a new induced movement illusion from global expansion or contraction in a triangular region filled with rising or falling textures. Objective global expansion or contraction induces lateral movement in the oblique edges of the triangle. The effects may be due to common and relative movements operating within a single texture.