Fragments of the earliest land plants

The earliest fossil evidence for land plants comes from microscopic dispersed spores. These microfossils are abundant and widely distributed in sediments, and the earliest generally accepted reports are from rocks of mid-Ordovician age (Llanvirn, 475 million years ago). Although distribution, morphology and ultrastructure of the spores indicate that they are derived from terrestrial plants, possibly early relatives of the bryophytes, this interpretation remains controversial as there is little in the way of direct evidence for the parent plants. An additional complicating factor is that there is a significant hiatus between the appearance of the first dispersed spores and fossils of relatively complete land plants (megafossils): spores predate the earliest megafossils (Late Silurian, 425 million year ago) by some 50 million years. Here we report the description of spore-containing plant fragments from Ordovician rocks of Oman. These fossils provide direct evidence for the nature of the spore-producing plants. They confirm that the earliest spores developed in large numbers within sporangia, providing strong evidence that they are the fossilized remains of bona fide land plants. Furthermore, analysis of spore wall ultrastructure supports liverwort affinities

A comparison of A-level performance in economics and business studies: how much more difficult is economics?

This paper uses ALIS data to compare academic performance in two subjects often viewed as relatively close substitutes for one another at A-level. The important role of GCSE achievement is confirmed for both subjects. There is evidence of strong gender effects and variation in outcomes across Examination Boards. A counterfactual exercise suggests that if the sample of Business Studies candidates had studied Economics nearly 40% of those who obtained a grade C or better in the former subject would not have done so in the latter. The opposite exercise uggests that 12% more Economics candidates would have achieved a grade C or better if they had taken Business Studies. In order to render a Business Studies A-level grade comparable to an Economics one in terms of relative difficulty, we estimate that a downward adjustment of 1.5 UCAS points should be applied to the former subject. This adjustment is lower than that suggested by correction factors based on conventional subject pair analysis for these two subjects

Cost-effectiveness of monitoring glaucoma patients in shared care: an economic evaluation alongside a randomized controlled trial

Background. Population aging increases the number of glaucoma patients which leads to higher workloads of glaucoma specialists. If stable glaucoma patients were monitored by optometrists and ophthalmic technicians in a glaucoma follow-up unit (GFU) rather than by glaucoma specialists, the specialists' workload and waiting lists might be reduced. We compared costs and quality of care at the GFU with those of usual care by glaucoma specialists in the Rotterdam Eye Hospital (REH) in a 30-month randomized clinical trial. Because quality of care turned out to be similar, we focus here on the costs. Methods. Stable glaucoma patients were randomized between the GFU and the glaucoma specialist group. Costs per patient year were calculated from four perspectives: those of patients, the Rotterdam Eye Hospital (REH), Dutch healthcare system, and society. The outcome measures were: compliance to the protocol; patient satisfaction; stability according to the practitioner; mean difference in IOP; results of the examinations; and number of treatment changes. Results. Baseline characteristics (such as age, intraocular pressure and target pressure) were comparable between the GFU group (n = 410) and the glaucoma specialist group (n = 405). Despite a higher number of visits per year, mean hospital costs per patient year were lower in the GFU group (€139 vs. €161). Patients' time and travel costs were similar. Healthcare costs were significantly lower for the GFU group (€230 vs. €251), as were societal costs (€310 vs. €339) (p < 0.01). Bootstrap-, sensitivity- and scenario-analyses showed that the costs were robust when varying hospital policy and the duration of visits and tests. Conclusion. We conclude that this GFU is cost-effective and deserves to be considered for implementation in other hospitals

Trends in day-case bladder outflow obstruction surgery: a study using Hospital Episode Statistics

This is the final version. Available from Wiley via the DOI in this record. Data Availability Statement. This report does not contain patient identifiable data. Data in this report are anonymized. The underlying HES data cannot be made available directly by the authors as the data were obtained under licence/data-sharing agreement from NHS Digital. HES data are available from NHS Digital upon application.OBJECTIVES: To describe the contemporary evolution of day-case bladder outflow obstruction (BOO) surgery in England and to profile day-case BOO surgery practices across England in terms of the types of operation performed and their safety profiles. MATERIALS AND METHODS: This was a retrospective observational analysis of Hospital Episode Statistics and UK Office for National Statistics data. All 111 043 recorded operations across 117 hospital trusts over 66 months, from 1 January 2017 to 30 June 2022, were obtained. Operations were identified as one of: transurethral resection of prostate (TURP); laser ablation or enucleation; vapour therapy; prostatic urethral lift (PUL); or bladder neck incision. Monthly day-case rate trends were plotted across the study period. Descriptive data, day-case rates and 30-day hospital readmissions were analysed for each operation type. Multilevel regression modelling with mixed effects was performed to determine whether day-case surgery was associated with higher 30-day hospital readmissions. RESULTS: Day-case patients were younger, with fewer comorbidities. Time series analysis showed a linear day-case rate increase from 8.3% (January 2017) to 21.0% (June 2022). Day-case rates improved for 92/117 trusts in 2021/2022 compared with 2017. Three of the six trusts with the highest day-case rates performed predominantly day-case TURP, and the other three laser surgery. Nationally, PUL and vapour surgery had the highest day-case rates (80.9% and 38.1%). Most inpatient operations were TURP. Multilevel regression modelling found reduced odds of 30-day readmission after day-case BOO surgery (all operations pooled), no difference for day-case vs inpatient TURP, and reduced odds following day-case LASER operations. CONCLUSIONS: The day-case rates for BOO surgery have linearly increased. Minimally invasive surgical technologies are commonly performed as day cases, whereas high day-case rates for TURP and for laser ablation operations are seen in a minority of hospitals. Day-case pathways to treat BOO can be safely developed irrespective of operative modality

The Getting It right First Time (GIRFT) programme in urology; rationale and methodology

This is the final version. Available on open access from Wiley via the DOI in this recordThe Getting It Right First Time (GIRFT) programme is a quality improvement initiative covering the National Health Service in England. The programme aims to standardise clinical practices and improve patient and system level outcomes by utilising data-driven insights and clinically-led recommendations. There are GIRFT workstreams for every medical and surgical specialty, including urology. Defining features of the GIRFT methodology are that it is clinically led by experienced clinicians, data-driven, and specialty specific. Each specialty workstream conducts deep-dive visits to every hospital, analysing performance data and engaging with clinicians and management to identify and share improvement priorities. For urology, GIRFT has completed deep-dive visits and published reports outlining priority areas for development. Reports include recommendations pertaining to streamlining care pathways, reducing the acuity of care environments, enhancing emergency services, optimising utilisation of outpatient services, and workforce training and utilisation. The GIRFT academy provides guides for implementing best practices specific to priority areas of care. These include important disease pathways, and GIRFT-advocated innovations such as urology investigation units and urology area networks. GIRFT offers clinical transformation, cost reduction, equity in access to care, and leaner models of care that are often more environmentally sustainable. Evaluation efforts of the programme have focussed on assessing the adoption of GIRFT recommendations, understanding barriers to change, and modelling the climate impact of advocated practices

Isolation and detection of circulating tumour cells from metastatic melanoma patients using a slanted spiral microfluidic device.

Circulating Tumour Cells (CTCs) are promising cancer biomarkers. Several methods have been developed to isolate CTCs from blood samples. However, the isolation of melanoma CTCs is very challenging as a result of their extraordinary heterogeneity, which has hindered their biological and clinical study. Thus, methods that isolate CTCs based on their physical properties, rather than surface marker expression, such as microfluidic devices, are greatly needed in melanoma. Here, we assessed the ability of the slanted spiral microfluidic device to isolate melanoma CTCs via label-free enrichment. We demonstrated that this device yields recovery rates of spiked melanoma cells of over 80% and 55%, after one or two rounds of enrichment, respectively. Concurrently, a two to three log reduction of white blood cells was achieved with one or two rounds of enrichment, respectively. We characterised the isolated CTCs using multimarker flow cytometry, immunocytochemistry and gene expression. The results demonstrated that CTCs from metastatic melanoma patients were highly heterogeneous and commonly expressed stem-like markers such as PAX3 and ABCB5. The implementation of the slanted microfluidic device for melanoma CTC isolation enables further understanding of the biology of melanoma metastasis for biomarker development and to inform future treatment approaches

Misaligned spin and orbital axes cause the anomalous precession of DI Herculis

The orbits of binary stars precess as a result of general relativistic effects, forces arising from the asphericity of the stars, and forces from additional stars or planets in the system. For most binaries, the theoretical and observed precession rates are in agreement. One system, however -- DI Herculis -- has resisted explanation for 30 years. The observed precession rate is a factor of four slower than the theoretical rate, a disagreement that once was interpreted as evidence for a failure of general relativity. Among the contemporary explanations are the existence of a circumbinary planet and a large tilt of the stellar spin axes with respect to the orbit. Here we report that both stars of DI Herculis rotate with their spin axes nearly perpendicular to the orbital axis (contrary to the usual assumption for close binary stars). The rotationally induced stellar oblateness causes precession in the direction opposite to that of relativistic precession, thereby reconciling the theoretical and observed rates.Comment: Nature, in press [11 pg

The Influence of Physiological Status on age Prediction of Anopheles Arabiensis Using Near Infra-red spectroscopy

Determining the age of malaria vectors is essential for evaluating the impact of interventions that reduce the survival of wild mosquito populations and for estimating changes in vectorial capacity. Near infra-red spectroscopy (NIRS) is a simple and non-destructive method that has been used to determine the age and species of Anopheles gambiae s.l. by analyzing differences in absorption spectra. The spectra are affected by biochemical changes that occur during the life of a mosquito and could be influenced by senescence and also the life history of the mosquito, i.e., mating, blood feeding and egg-laying events. To better understand these changes, we evaluated the influence of mosquito physiological status on NIR energy absorption spectra. Mosquitoes were kept in individual cups to permit record keeping of each individual insect’s life history. Mosquitoes of the same chronological age, but at different physiological stages, were scanned and compared using cross-validations. We observed a slight trend within some physiological stages that suggest older insects tend to be predicted as being physiologically more mature. It was advantageous to include mosquitoes of different chronological ages and physiological stages in calibrations, as it increases the robustness of the model resulting in better age predictions. Progression through different physiological statuses of An. arabiensis influences the chronological age prediction by the NIRS. Entomologists that wish to use NIR technology to predict the age of field-caught An. gambiae s.l from their study area should use a calibration developed from their field strain using mosquitoes of diverse chronological ages and physiological stages to increase the robustness and accuracy of the predictions.\u

Mutual information rate and bounds for it

The amount of information exchanged per unit of time between two nodes in a dynamical network or between two data sets is a powerful concept for analysing complex systems. This quantity, known as the mutual information rate (MIR), is calculated from the mutual information, which is rigorously defined only for random systems. Moreover, the definition of mutual information is based on probabilities of significant events. This work offers a simple alternative way to calculate the MIR in dynamical (deterministic) networks or between two data sets (not fully deterministic), and to calculate its upper and lower bounds without having to calculate probabilities, but rather in terms of well known and well defined quantities in dynamical systems. As possible applications of our bounds, we study the relationship between synchronisation and the exchange of information in a system of two coupled maps and in experimental networks of coupled oscillators

A model for reactive porous transport during re-wetting of hardened concrete

A mathematical model is developed that captures the transport of liquid water in hardened concrete, as well as the chemical reactions that occur between the imbibed water and the residual calcium silicate compounds residing in the porous concrete matrix. The main hypothesis in this model is that the reaction product -- calcium silicate hydrate gel -- clogs the pores within the concrete thereby hindering water transport. Numerical simulations are employed to determine the sensitivity of the model solution to changes in various physical parameters, and compare to experimental results available in the literature.Comment: 30 page