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Background: Perioperative atrial fibrillation (AF) and myocardial injury after noncardiac surgery (MINS) are common complications after noncardiac surgery. Inflammation has been implicated in the pathogenesis of both disorders. The COP-AF trial tests the hypothesis that colchicine reduces the incidence of perioperative AF and MINS in patients undergoing major noncardiac thoracic surgery. Design: The 'COlchicine for the Prevention of Perioperative Atrial Fibrillation' (COP-AF) trial is an international, blinded, randomized trial that compares colchicine to placebo in patients aged at least 55 years and undergoing major noncardiac thoracic surgery with general anesthesia. Exclusion criteria include a history of AF and a contraindication to colchicine (e.g., severe renal dysfunction). Oral colchicine at a dose of 0.5 mg or matching placebo is given within 4 hours before surgery. Thereafter, patients receive colchicine 0.5 mg or placebo twice daily for a total of 10 days. The two independent co-primary outcomes are clinically important perioperative AF (including atrial flutter) and MINS during 14 days of follow-up. The main safety outcomes are sepsis or infection and non-infectious diarrhea. We aim to enroll 3,200 patients from approximately 40 sites across 11 countries to have at least 80% power for the independent evaluation of the two co-primary outcomes. Summary: COP-AF is a large randomized and blinded trial designed to determine whether colchicine reduces the risk of perioperative AF or MINS in patients who have major noncardiac thoracic surgery. Population Health Research Institute

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is highly contagious and has caused significant medical/socioeconomic impacts. Other than vaccination, effective public health measures, including contact tracing, isolation, and quarantine, is critical for deterring viral transmission, preventing infection progression and resuming normal activities. Viral transmission is affected by many factors, but the viral load and vitality could be among the most important ones. Although in vitro studies have indicated that the amount of virus isolated from infected individuals affects the successful rate of virus isolation, whether the viral load carried at the individual level would determine the transmissibility was unknown. We examined whether the cycle threshold (Ct) value, a measurement of viral load by RT-PCR assay, could differentiate the spreaders from the non-spreaders in a population of college students. Our results indicate that while at the population level the Ct value is lower, suggesting a higher viral load, in the symptomatic spreaders than that in the asymptomatic non-spreaders, there is a significant overlap in the Ct values between the two groups. Thus, Ct value, or the viral load, at the individual level could not predict the transmissibility. Instead, a sensitive method to detect the presence of virus is needed to identify asymptomatic individuals who may carry a low viral load but can still be infectious.

Purpose Cutaneous melanoma metastatic to the vitreous is very rare. This study investigated the clinical findings, treatment, and outcome of patients with metastatic cutaneous melanoma to the vitreous. Most patients received checkpoint inhibition for the treatment of systemic disease, and the significance of this was explored. Design Multicenter, retrospective cohort study. Participants Fourteen eyes of 11 patients with metastatic cutaneous melanoma to the vitreous. Methods Clinical records, including fundus photography and ultrasound results, were reviewed retrospectively, and relevant data were recorded for each patient eye. Main Outcome Measures Clinical features at presentation, ophthalmic and systemic treatments, and outcomes. Results The median age at presentation of ophthalmic disease was 66 years (range, 23–88 years), and the median follow-up from diagnosis of ophthalmic disease was 23 months. Ten of 11 patients were treated with immune checkpoint inhibition at some point in the treatment course. The median time from starting immunotherapy to ocular symptoms was 17 months (range, 4.5–38 months). Half of eyes demonstrated amelanotic vitreous debris. Five eyes demonstrated elevated intraocular pressure, and 4 eyes demonstrated a retinal detachment. Six patients showed metastatic disease in the central nervous system. Ophthalmic treatment included external beam radiation (30–40 Gy) in 6 eyes, intravitreous melphalan (10–20 μg) in 4 eyes, enucleation of 1 eye, and local observation while receiving systemic treatment in 2 eyes. Three eyes received intravitreous bevacizumab for neovascularization. The final Snellen visual acuity ranged from 20/20 to no light perception. Conclusions The differential diagnosis of vitreous debris in the context of metastatic cutaneous melanoma includes intravitreal metastasis, and this seems to be particularly apparent during this era of treatment with checkpoint inhibition. External beam radiation, intravitreous melphalan, and systemic checkpoint inhibition can be used in the treatment of ophthalmic disease. Neovascular glaucoma and retinal detachments may occur, and most eyes show poor visual potential. Approximately one quarter of patients demonstrated ocular disease that preceded central nervous system metastasis. Patients with visual symptoms or vitreous debris in the context of metastatic cutaneous melanoma would benefit from evaluation by an ophthalmic oncologist.

Dysregulated wound healing after burn injury frequently results in debilitating hypertrophic scarring and contractures. Myofibroblasts, the main effector cells for dermal fibrosis, develop from normal fibroblasts via transforming growth factor beta 1 (TGF-β1). During wound healing, myofibroblasts produce extracellular matrix (ECM) proteins, modulate ECM stability, and contract the ECM using alpha smooth muscle actin (α-SMA) in contractile stress fibers. The antifibrotic pirfenidone has previously been shown to inhibit the initial differentiation of fibroblasts into myofibroblasts in vitro and act as a prophylactic measure against hypertrophic scar development in a mouse burn model. To test whether pirfenidone affects differentiated myofibroblasts, we investigated the in vitro effects of pirfenidone treatment after three to five days of stimulation with TGF-β1. In assays for morphology, protein and gene expression, and contractility, pirfenidone treatment produced significant effects. Profibrotic gene expression returned to near-normal levels, further α-SMA protein expression was prevented, and cell contraction within a stressed collagen matrix was reduced. These in vitro results promote pirfenidone as a promising antifibrotic agent to treat existing scars and healing wounds by mitigating the effects of differentiated myofibroblasts.

Ancient shoreline–shelf depositional systems are influenced by an unusually wide array of geological, biological and hydrodynamic processes, with sediment transport and deposition primarily determined by the interaction of river, wave (including storm) and tidal processes, and changes in relative sea level. Understanding the impact of these processes on shoreline–shelf morphodynamics and stratigraphic preservation remains challenging. Numerical modelling integrated with traditional facies analysis provides an increasingly viable approach, with the potential to quantify, and thereby improve understanding of, the impact of these complex coastal sedimentary processes. An integrated approach is presented here that focuses on palaeotidal modelling to investigate the controls on ancient tides and their influence on sedimentary deposition and preservation – one of the three cornerstones of the ternary process classification scheme of shoreline-shelf systems. Numerical tidal modelling methodology is reviewed and illustrated in three palaeotidal model case studies of different scales and focus. The results are synthesised in the context of shoreline–shelf processes, including a critique and modification of the process-based classification scheme. The emphasis on tidal processes reflects their global importance throughout Earth’s history. Ancient palaeotidal models are able to highlight and quantify the following four controls on tidal processes: (1) the physiography (shape and depth) of oceans (1000s km scale) determines the degree of tidal resonance; (2) the physiography of ocean connections to partly enclosed water bodies (100–1000s km scale) determines the regional-scale flux of tidal energy (inflow versus outflow); (3) the physiography of continental shelves influences shelf tidal resonance potential; and (4) tides in relatively local-scale embayments (typically 1–10s km scale) are influenced by the balance of tidal amplification due to funnelling, shoaling and resonance effects versus frictional damping. In deep time, palaeogeographic and palaeobathymetric uncertainty can be accounted for in palaeotidal models by performing sensitivity analyses to different scenarios, across this range of spatial scales. These tidal process controls are incorporated into an updated predictive decision tree for determining shoreline–shelf process regime in terms of the relative interaction of wave, fluvial and tidal processes. The predictive decision tree considers the effects of basin physiography, shelf width and shoreline morphology on wave, fluvial and tidal processes separately. Uncertainty and ambiguity in applying the widely used three-tier process classification scheme are reduced by using the decision tree in conjunction with a proposed two-tier classification of process regime that is limited to primary and secondary processes. This two-tier classification scheme is illustrated in the three case studies, showing how integration of numerical modelling with facies analysis of the preserved stratigraphic record improves confidence in prediction of tide-influenced shoreline-shelf process regimes. Wider application of this approach will further improve process-based classifications and predictions of modern and ancient shoreline–shelf systems.

Land management that improves soil quality is known to increase the amount of water-stable soil aggregates, but many current soil erosion models do not consider land management effects when estimating the size distribution of eroded sediment. Our objective was to develop a method to improve eroded sediment size estimates in response to alternative land management practices using information available within the RUSLE2 model and its database. We conducted a literature search identifying 274 soil aggregate size distributions where soil clay and soil organic carbon were also reported. The median value and log-normal standard deviation were estimated for each distribution. Median value was found to be linearly related to soil clay fraction and quadratically related to soil carbon content. However, the 10% of samples with observed median aggregate sizes greater than 3 mm were all underestimated by the regression model. All these samples were collected from soils under land use described as grass, pasture, or forest. To then determine whether incorporating management impacts on size distribution could better fit field data than this simple approach based purely on clay and carbon, algorithms termed MAS (Model of Aggregated Sediment) were derived and applied with default values in the RUSLE2 soil erosion model to estimate a coarser sediment size distribution at the point of detachment for land management with increased biomass inputs and reduced tillage disturbances. The MAS estimates of macroaggregated sediment (>0.212 mm) mirrored fragment size observations made over 10 yr when cropland was converted to prairie in the central U.S.A. Thus, MAS estimated dynamic land management effects on aggregation better than regression relationships based solely on soil clay and carbon contents. More aggregate and sediment size datasets that include historical land use information will be needed to fully assess the generality of the MAS algorithms and parameter estimates.

Accurate soil erosion monitoring provides a basis for soil erosion prediction and prevention. Channel bank erosion quantification is prerequisite to couple effectively the bank sediment supply system with fluvial sediment transport fluxes. The objectives of this study were to describe and evaluate methods for monitoring and data post-analysis of channel widening in the presence of a non-erodible layer. Technology was developed to capture 5-cm spaced cross-sections along a soil flume at 3-s time intervals. Two off-the-shelf digital cameras were positioned 3-m above the soil bed and controlled by a program to trigger simultaneously and download images to the computer. Methods utilizing color differences in images and elevation differences in DEMs were applied to detect discontinuities between channel walls and the soil bed. Channel widths were calculated by differentiating the coordinates of these surface discontinuities. A volumetric method was used to calculate flow velocity with measurements of flow depths obtained from ultrasonic depth sensors. Sediment concentration was determined by manual sampling. The results showed that different channel width calculation methods exhibited comparable outcomes and achieved satisfactory accuracy. Sediment discharge showed a significant positive linear correlation with channel widening rate, while exhibiting a 5 to 25-s time lag compared to the peak of channel widening rate. Total sediment discharge calculated by photogrammetry was 3.1% lower than that calculated by manual sampling. Flow velocity decreased with time and showed a significant negative power correlation with channel width. Advantages of the described methodology include automated high spatial and temporal monitoring resolution, semi-automated data post-processing, and the potential to be generalized to large scale river/reservoir bank failure monitoring.

Watershed-scale simulation technology allows quantification of the impact of individual and/or integrated management practices throughout the watershed. In the AnnAGNPS watershed-scale model, the watershed is subdivided into basic modeling units (fields) in which all spatially varying physical parameters are assumed to be homogeneous. Conversely, RUSLE2 model can estimate sediment yield at sub-field scale with enhanced characterization capabilities. In this study, an integrated approach was developed and evaluated that combines both models for enhanced representation of individual fields while accounting for the watershed-wide integrated intra fields effect when routing sediment loads through the watershed. Critical sediment producing areas identified through integrated RUSLE2 erosion and AnnAGNPS sediment transport models can be used to support the development and evaluation of conservation management plans specific to fields but impacting the entire watershed.

Soil erosion by water remains a major problem in many regions of the world and in many cases the dominant source of sediment is from gully erosion. Filling-in ephemeral gullies by mechanical operations serves to maintain high erosion rates and degrades the soil from areas used for filling, however, the impact of gully filling on soil quality is uncertain. The objective was to quantify the impact of filling of an ephemeral gully on crop yield and soil quality adjacent to the gully. An ephemeral gully was sampled for in situ physical (topsoil depth, soil color, shear strength, soil penetration resistance) properties and hydraulic (bulk density, saturated hydraulic conductivity, water retention) properties from undisturbed cores in a field in the sixth consecutive year of No-Till. The field was selectively resampled the following year immediately following tillage. Soil properties were measured and sampled every 7.6 m out to 37 m from each side of the gully center along five transects perpendicular to the gully and a similar transect removed from the gully to represent baseline conditions. Filling of the gully by scraping soil from upper convex slope positions significantly reduced corn yield. The best indicators of soil physical quality were depth of topsoil, shear strength at the surface, and soil penetration resistance at the 5 cm depth and the best hydraulic properties were saturated hydraulic conductivity and several water retention characteristics. However, the slope of the retention curve at its inflection point was not found to be an indicator of soil physical quality. Every 1 cm loss of topsoil resulted in a 3.3 to 6.5% loss in yield. The soil physical quality indicators were dramatically changed by tillage such that the index developed was no longer appropriate. Future efforts need to address the dynamic changes in the soil quality index following tillage due to reconsolidation of the soil and whether inclusion of chemical and biological indicators would be less impacted by tillage.

To illustrate the potential burden of SARS-CoV-2 epidemics within the most vulnerable countries in Africa, we simulated a SARS-CoV-2 outbreak in DR Congo in the absence of interventions Using an age-structured epidemiological model (appendix p 1), and assuming a basic reproductive number of 2 72 (95% CI 2 56-2 87),2 we estimate that there would be 76 213 155 infections (95% CI 74 156 965-77 800 029) and 319 441 deaths (313 079-324 175) in the absence of physical distancing Although individuals younger than 20 years account for 42 752 770 (95% CI 41 551 696-43 683 014;56 1%) of these simulated SARS-CoV-2 infections, individuals aged 50 years and older constitute 280 623 (275 356-284 509;87-8%) of the deaths in our model prediction Given the high prevalence of comorbidities in DR Congo, as there is in Africa more broadly, the death toll could even be much higher

BackgroundNumerous countries imposed strict travel restrictions, contributing to the large socioeconomic burden during the COVID-19 pandemic. The long quarantines that apply to contacts of cases may be excessive for travel policy.MethodsWe developed an approach to evaluate imminent countrywide COVID-19 infections after 0–14-day quarantine and testing. We identified the minimum travel quarantine duration such that the infection rate within the destination country did not increase compared to a travel ban, defining this minimum quarantine as “sufficient.”FindingsWe present a generalised analytical framework and a specific case study of the epidemic situation on November 21, 2021, for application to 26 European countries. For most origin-destination country pairs, a three-day or shorter quarantine with RT-PCR or antigen testing on exit suffices. Adaptation to the European Union traffic-light risk stratification provided a simplified policy tool. Our analytical approach provides guidance for travel policy during all phases of pandemic diseases.InterpretationFor nearly half of origin-destination country pairs analysed, travel can be permitted in the absence of quarantine and testing. For the majority of pairs requiring controls, a short quarantine with testing could be as effective as a complete travel ban. The estimated travel quarantine durations are substantially shorter than those specified for traced contacts.FundingEasyJet (JPT and APG), the Elihu endowment (JPT), the Burnett and Stender families’ endowment (APG), the Notsew Orm Sands Foundation (JPT and APG), the National Institutes of Health (MCF), Canadian Institutes of Health Research (SMM) and Natural Sciences and Engineering Research Council of Canada EIDM-MfPH (SMM).Research in contextEvidence before this studyEvidence from early in the pandemic indicates that border closures at the epicentre slowed global dissemination of COVID-19. As community transmission became established in many nations, studies have suggested that the benefit of strict border closures in mitigating the transmission of disease from travellers diminished. Research for community settings has shown that testing later during quarantine, rather than upon entry into quarantine, can substantially shorten the duration of quarantine needed to reduce post-quarantine transmission. In particular for international air travellers, a 14-day quarantine can effectively be shortened to five or seven days. The number of infectious COVID-19 cases that escape from these quarantines depends on the prevalence of disease in the country the traveller originated as well as the travel volume into the country.Added value of this studyWe developed a framework to identify quarantine and testing strategies that enable travel from specific origins without increasing their infection rates per capita within destinations. No prior study has evaluated the appropriate duration of quarantine necessary to prevent any rise in infection rates per capita in the destination countries as a result of travel. By accounting for prevalence, daily incidence, vaccine coverage, immunity, age demographics, and travel flow between countries, we quantified the contribution of travel towards within-country the imminent infections in the destination country under different quarantine and testing strategies. For travel between 26 European countries, our results for the pandemic situation observed on November 21, 2021 demonstrate that there are often less burdensome quarantine and testing strategies that can serve as effective alternatives to strict border closure. Specifically, these estimated sufficient quarantine durations are especially dependent on COVID-19 prevalence and immunity within the two countries. We also found that asymmetry in the travel flow, just not the volume of travel flow, can also influence the estimated sufficient quarantine durations. Using data on variants of concern, including Omicron, we found that the adequacy of a border control strategy to limit variant spread depends strongly on the geographical distribution of the variant. While our results pertain to European countries, we also provide an interactive spreadsheet that can be used to determine appropriate quarantine durations between any two countries. Moreover, our framework can also be applied at any spatial or population scale within which movement restrictions could feasibly be implemented.Implications of all available evidenceTravel quarantine and testing strategies can effectively mitigate importation and onward transmission within a country. Identifying sufficient strategies can allow countries to permit travel to and from other countries, without risking a short-term increase in infection rates. As long as the community transmission is occurring, the long-term epidemic trend within the destination country is more apt to be determined by other disease control measures, e.g., contact tracing, vaccination, and non-pharmaceutical interventions. Together, travel quarantine and other related control measures can mitigate the risk of transmission between countries, limiting the threat of variants of concern.

Pirfenidone (PFD) is a synthetic small molecule inhibitor with demonstrated anti-inflammatory and antifibrotic properties in vitro and in vivo. The exact mechanism(s) of PFD action remain unclear, due in part to the broad effects of this drug on the complex processes involved in inflammation and fibrosis. While PFD is FDA-approved for the treatment of idiopathic pulmonary fibrosis, the efficacy of this compound for the treatment of dermal fibrosis has not yet been fully characterized. Dermal fibrosis is the pathological formation of excess fibrous connective tissue of the skin, usually the result of traumatic cutaneous injury. Fibroproliferative scarring, caused by delayed wound healing and prolonged inflammation, remains a major clinical concern with considerable morbidity. Despite efforts to identify a therapeutic that targets the fibrotic pathways involved in wound healing to mitigate scar formation, no satisfactory dermal antifibrotic has yet been identified. We aim to better elucidate the antifibrotic mechanism(s) of PFD activity using an in vitro model of dermal fibrosis. Briefly, cultured human dermal fibroblasts were stimulated with TGF-β1 to induce differentiation into profibrotic myofibroblast cells. A dose-dependent reduction in cellular proliferation and migration was observed in TGF-β1-stimulated cells when treated with PFD. We observed a clear inhibition in the development of essential myofibroblast mechanoregulatory machinery, including contractile F-actin stress fibers containing α-SMA and large super-mature focal adhesions. PFD treatment significantly reduced protein levels of major ECM components type I and type III collagen. PFD targeted the p38 MAPK signaling pathway and mitigated profibrotic gene expression profiles. This in vitro data promotes PFD as a potential therapeutic agent for the treatment of dermal fibrosis.

Gully erosion contributes large amounts of sediment within watersheds around the world. Gully widening constitutes about 80% of total soil loss, especially in the presence of a plow pan which manifests a less or non-erodible soil layer. Current knowledge on sidewall toe scour (scour arcs) and tension crack processes in gully widening is limited. Thus, simulated channel sidewall expansion tests, where the channel bed was fixed to represent a non-erodible layer, were designed to investigate how inflow rate, slope gradient and initial channel width affect channel widening processes. Soil boxes (2.0 m-long, 0.3 m-wide and 0.5 m-deep) with two slope gradients (15° and 20°), four inflow rates (1.0, 2.0, 3.0 and 4.0 L min −1 ) and two initial channel widths (4 and 8 cm) were subjected to clear-water overland flow. Photogrammetry was used to detect tension crack and width variations of channels. The results show that sediment delivery and channel width increase with the increase of inflow rate, bed slope and the decrease of initial channel width. Exponential equations were used to predict the channel width time series. Time lag occurred between sediment peak and soil block failure. Toe scour, crack development, sidewall failure and block detachment and transport, in sequence, were the four main processes of channel widening. Basal scour arc length, tension crack length and width decreased with initial channel width and increased with time, flow discharge and bed slope. Basal scour arcs were divided into three patterns according to different shapes in comparison to the failure arcs. Sediment delivery equations based on the disaggregation of concentrated flow entrainment and mass failure were also fitted. This study provides new insight on improving gully erosion measurements and prediction technology.

High-resolution infra-red spectra of KY 3 F10 nanoparticles doped with Nd 3 + and Er 3 + are measured in magnetic fields of up to 4 T. A simple model of the magnetic splittings of the ground and excited states is used to show that the presence or absence of observable splittings depends on the anisotropy of the response to the magnetic field. Detailed crystal-field calculations accurately model the spectra, including nonlinear effects.

We present a detailed investigation of the dynamics of impurity-trapped excitons in CaF 2 :Yb 2+ using transient photoluminescence enhancement induced via a two-frequency, sequential excitation process employing a UV optical parametric amplifier (OPA) synchronized to an infrared free electron laser (FEL). The temporal behaviour is well approximated by a multi-level rate equation model as relaxation between excited states of the exciton as well as a small contribution from local lattice heating by the FEL which becomes evident due to the 40 cm −1 splitting of the exciton excited states giving rise to the transient photoluminescence enhancement itself.

Most conventional chemotherapeutics have narrow therapeutic windows, and thus their delivery remains challenging and often raises safety and efficacy concerns. Theranostic platforms, with simultaneous encapsulation of therapeutic and diagnostic agents, have been proposed as next-generation formulations which can overcome this issue. In this work, we used electrohydrodynamic approaches to fabricate core@shell formulations comprising a pH responsive Eudragit L100 shell embedded with superparamagnetic iron oxide nanoparticles (SPIONs), and a thermo-responsive poly(N-isopropylacrylamide) (PNIPAM)/ethyl cellulose core loaded with the model drug carmofur. By varying the weight ratio of core polymer to shell polymer, the morphology of PNIPAM/ethyl cellulose@Eudragit L100 microparticles could be changed from concave to spherical. Smooth cylindrical fibres could also be generated. All the formulations exist as amorphous solid dispersions of drug-in-polymer, with distinct core@shell architectures. The fibres have clear thermo-responsive drug release profiles, while no thermo-responsive properties can be seen with the particles. All the formulations can protect SPIONs from degradation in gastric fluids (pH ∼ 1.5), and around the physiological pH range the materials offer effective and pH-responsive relaxivity. The r2 values also display clear linear relationships with drug release data, suggesting the potential of using MRI signals to track drug release in vivo. Mathematical equations were established to track drug release in vitro, with very similar experimental and predicted release profiles obtained.

We report on an interpretation of the 4f → 5d absorption and fluorescence spectra as well as the previously un-reported intra-4f transitions between the Stark levels of the 2F5/2 and 2F7/2 multiplets of the single seven-fold coordinated, C1 symmetry site for Ce3+ in Y2SiO5. Further, We also give the corresponding crystal-field parameters determined by fitting to the observed energy level data and the ground state Zeeman g tensor obtained from previously reported electron paramagnetic resonance (EPR) measurements. Finally we present a temperature-dependent analysis of the linewidth and position of the 4f → 4f absorption lines.

We report on laser site-selective spectroscopy, as well as high resolution, infrared to optical absorption, of both the six and seven -fold coordinated, C1 symmetry sites for Nd3+ doped Y2SiO5. A total of fifty three crystal-field energy levels have been determined for both sites. We also present the temperature dependencies of the spectral linewidth and line position as measured in absorption. The coupling coefficients due to Raman two-phonon and direct one-phonon processes are interpreted in terms of the phonon energies contributing and their roles in the phonon energy distribution of Y2SiO5. Finally, we analyse direct non-radiative relaxation processes as inferred from the temperature-dependent fluorescence lifetimes.

The submerged Jet Erosion Test (JET) is a commonly used technique to assess the erodibility of cohesive soil. Employing a linear excess shear stress equation and impinging jet theory, simple numerical methods have been developed to analyze data collected using a JET to determine the critical shear stress and erodibility coefficient of soil. These include the Blaisdell, Iterative, and Scour Depth Methods, and all have been organized into easy to use spreadsheet routines. The analytical framework of the JET and its associated methods, however, are based on many assumptions that may not be satisfied in field and laboratory settings. The main objective of this study is to critically assess this analytical framework and these methodologies. Part of this assessment is to include the effect of flow confinement on the JET. The possible relationship between the derived erodibility coefficient and critical shear stress, a practical tool in soil erosion assessment, is examined, and a review of the deficiencies in the JET methodology also is presented. Using a large database of JET results from the United States and data from literature, it is shown that each method can generate an acceptable curve fit through the scour depth measurements as a function of time. The analysis shows, however, that the Scour Depth and Iterative Methods may result in physically unrealistic values for the erosion parameters. The effect of flow confinement of the impinging jet increases the derived critical shear stress and decreases the erodibility coefficient by a factor of 2.4 relative to unconfined flow assumption. For a given critical shear stress, the length of time over which scour depth data are collected also affects the calculation of erosion parameters. In general, there is a lack of consensus relating the derived soil erodibility coefficient to the derived critical shear stress. Although empirical relationships are statistically significant, the calculated erodibility coefficient for a given critical shear stress has an uncertainty of several orders of magnitude. This study shows that JET results should be used with caution and the magnitude of the uncertainty in the derived erodibility parameters should be carefully considered.

Near infrared absorption of cubic phase KY3F10 nanoparticles co-doped with Yb3+ and Er3+ is studied. The application of magnetic fields up to 4 T yields measurable splittings of the Kramers doublets of the Yb3+ and Er3+ ions within the randomly oriented nanoparticle ensemble. The magnetic splittings are accurately modelled by a parametrised crystal-field Hamiltonian approach. This modelling has considerable potential for enabling the use of magnetic-field induced energy transfer enhancement in optical bio-sensors and other applications.

Background: Black populations in the United States are being disproportionately affected by the COVID-19 pandemic, but the increased mortality burden after accounting for health and other demographic characteristics is not well understood. We examined characteristics of individuals who died from COVID-19 in Michigan by race stratified by their age, sex and comorbidity prevalence to illustrate and understand this disparity in mortality risk. Methods: We evaluate COVID-19 mortality in Michigan by demographic and health characteristics, using individual-level linked death certificate and surveillance data collected by the Michigan Department of Health and Human Services from March 16 to October 26, 2020. We identified differences in demographics and comorbidity prevalence across race among individuals who died from COVID-19 and calculated mortality rates by age, sex, race, and number of comorbidities. Findings: Among the 6,065 COVID-19 related deaths in Michigan, Black individuals are experiencing 3·6 times the mortality rate of White individuals (p

Purpose Previous studies have associated developmental stuttering with difficulty learning new motor skills. We investigated non-speech motor sequence learning in children with persistent developmental stuttering (CWS), children who have recovered from developmental stuttering (CRS) and typically developing controls (CON). Methods Over the course of two days, participants completed the Multi-Finger Sequencing Task, consisting of repeated trials of a10-element sequence, interspersed with trials of random sequences of the same length. We evaluated motor sequence learning using accuracy and response synchrony, a timing measure for evaluation of sequencing timing. We examined error types as well as recognition and recall of the repeated sequences. Results CWS demonstrated lower performance accuracy than CON and CRS on the first day of the finger tapping experiment but improved to the performance level of CON and CRS on the second day. Response synchrony showed no overall difference among CWS, CRS and CON. Learning scores of repeated sequences did not differ from learning scores of random sequences in CWS, CRS and CON. CON and CRS demonstrated an adaptive strategy to response errors, whereas CWS maintained a high percentage of corrected errors for both days. Conclusions Our study examined non-speech sequence learning across CWS, CRS and CON. Our preliminary findings support the idea that developmental stuttering is not associated with sequence learning per se but rather with general fine motor performance difficulties.

We report on a method of employing spin Hamiltonian data to enhance the accuracy of crystal-field fits for rare-earth impurity sites of low symmetry in crystalline hosts. As an initial test of this method, we apply it to orthorhombic sites in Li+ and Na+ ion charge compensated Sm3+ centers in codoped CaF2 and SrF2 crystals. This yields a good agreement between theory and experiment, in addition to accurately modelling crystal strains due to the differing ionic radii of Li+ and Na+.

Hydrostatic pressures of up to 200 kbar have been employed to influence the spectroscopic properties of MgF 2 doped with divalent ytterbium. MgF 2 :Yb 2+ exhibits a broad band emission peaked at 485 nm related to the 4f 13 5d 1 →4f 14 transition of Yb 2+ . At pressures between ambient and 92 kbar, a red-shift of the luminescence maximum was observed, whilst simultaneously the decay time of the emission gradually decreased. Abrupt changes were observed in the emission spectra at 92 and 145 kbar which were related to the phase transitions of the host lattice induced by pressure. It has been shown that pressure does not change energetic structure of three first excited states of Yb 2+ in the rutile phase but is responsible for an increase in the probability of non-radiative depopulation of the first excited triplet state from the 4f 13 5d 1 electronic configuration.

We report on studies of the Yb3+ ion absorption in Er3+ co-doped cubic and hexagonal phase NaYF4 upconverting nanoparticles using high-resolution absorption measurements. The Yb3+ absorption spectra have intense maxima at 10266.1 cm−1 and 10237.0 cm−1 for the cubic and hexagonal phases respectively, which is far from the most commonly used laser diode wavelength. Resonant excitation of these absorption maxima yields a ~40% (cubic) and ~34% (hexagonal) enhancement of the 2H11/2, 4S3/2 and 4F9/2 visible upconversion fluorescence. The hexagonal phase material exhibits Er3+ upconversion fluorescence which is a factor of 104 brighter than that obtained from the cubic phase nanoparticles, irrespective of their sizes, morphologies and Ln3+ ion distribution. The upconversion excitation spectra show preliminary evidence of excited state absorption features when monitoring 4F9/2 fluorescence for the hexagonal phase material.

We report on laser site selective spectroscopy of a single crystal Y2SiO5 doped with trivalent samarium ions. For crystals having a dopant concentration of 0.5 molar percent, energy is observed to be exchanged between ions occupying sites of the same local configuration (intra-site transfer) and between ions occupying sites of different ‘local symmetry’ (inter-site transfer). The inter-ionic cross relaxation is inferred to occur via a dipole–dipole mechanism.

Crystal-field parameters are extracted from ab initio calculations of the energy level structure of the 4 f 2 and 4 f 5 d configurations for Pr 3 + as a free ion and doped into Ca F 2 and Lu 2 O 3 crystals. The parameters are compared to those derived from direct phenomenological fits to experimental levels. The ab initio crystal-field parameters are in good agreement with experiment. For the ab initio calculations the F 2 Coulomb parameter is consistently larger, and the electron correlation configuration interaction parameter α is up to a factor of three larger, than the experimental parameters. This is consistent with previous calculations that suggest that significant contributions to electron correlation arise from continuum states.

In atomic physics experiments, external cavity diode lasers (ECDLs) are often coupled with tapered amplifiers (TPAs) to provide a highly tunable laser source that also has relatively high output power. Usually these systems are mounted on separate baseplates in separate housings, and when the coupling optics are taken into account, the entire system can take up a large amount of optical table space. Here we report the design, construction, coupling and characterization of an ECDL-TPA system where the ECDL, TPA and coupling optics are mounted on a single, enclosable baseplate. During design and construction, thermal management had a strong influence on the final design, therefore thermal measurements and discussion is emphasized. We report that the output power and frequency was stable over the measurement period. The system is composed of commercially available optical components, and readily machined mounting parts. The system exhibits the possibility of further miniaturization for space-limited applications, and portability.

Purpose A revised U.S. heart allocation system (HAS) instituted 10/18/18 was designed to eliminate donation service area (DSA) boundaries/reduce geographic disparity. The new status 1-3 is equivalent to the old status 1A. The effect of HAS change on DSA and heart transplant program (HTP) logistics are unknown. We report our DSA and HTP experience 1 year later. Methods Data from 2 groups of patients defined by date of transplant were analyzed: pre HAS change (PRE, 10/18/17-10/17/18) and post HAS change (POST, 10/18/18-9/30/19). The data from our local DSA and our HTP PRE and POST are reported separately. Results Our local DSA has 2 adult/1 pediatric HTPs. During the PRE, the DSA recovered 65 adult hearts (30 allocated to our HTP, 13 to 2nd adult HTP, 1 to pediatric HTP). 21 hearts were allocated outside of the DSA (32.3%). 40 hearts were allocated to status 1A (62%). During the POST, the DSA recovered 75 adult hearts (10 allocated to our HTP, 4 to 2nd adult HTP). 61 (81.3%) hearts were allocated outside the DSA. 84% were allocated to the old status 1A equivalent (new status 1-3). Table illustrates our HTP statistics PRE and POST. 38 transplants were performed PRE, and 40 performed POST. Cold ischemic time increased 21% from 161 to 195 minutes. Flights were required in 15 PRE and 34 POST cases. While the miles per flight were similar PRE and POST (331 vs 354 nautical miles [nm]), the total nm increased 2.4 fold from 4969 to 12032. Travel time increased 25% from 251 to 315 minutes. Total organ acquisition cost increased 36% per transplant POST vs PRE. Conclusion After HAS change, 81% (vs 32%) of hearts were allocated outside the DSA and to the most urgent statuses (84 vs 62%). HAS change led to significant increase in cold ischemic time (21%), travel time (25%)/distance (242%), need for procurement team flyout (34 vs 15) and per transplant organ acquisition cost (36%). Further analysis are needed to examine the impact of HAS on procurement logistics, HTP cost, surgeon travel safety and post transplant survival.

Consolidation of soil by wetting and drying cycles following tillage rapidly changes the soil physical properties but little is known about how these changes impact soil erosion. The objective of this study was to develop equations to predict soil erodibility (Kd) and critical shear stress (τc) in response to consolidation based upon changes in soil bulk density, saturated hydraulic conductivity, water content, soil penetration strength and surface shear strength following a series of wetting and drying cycles. Air-dried soil from four contrasting soil series was loosely filled into 20 soil cylinders (80 total) to simulate freshly tilled conditions. Soil physical and erosion properties were determined at six time periods (0, 1, 3, 5, 7, 10 days) following daily simulated rainfall of 33 mm h−1 for 1 h and 24 h of drainage/drying. The Jet Test device was used to determine Kd, and τc. The bulk density increased with time due to consolidation following the simulated precipitation events with the largest increase (50–100 % of the total) occurring after the first wetting/drying cycle. The Onstad consolidation model tended to over-predict this initial surface bulk density increase, whereas, an exponential model better represented the surface and depth-averaged bulk density changes for the four soils tested. The shear strength and soil penetration resistance increased dramatically after the first wetting/drying cycle then decreased to a fairly stable value in response to subsequent wetting/drying cycles. The saturated hydraulic conductivity, Ks, decreased so rapidly with accumulated rainfall that an exponential decay model could not match the decrease in Ks as the soil consolidated. The best indicators of erodibility response to consolidation were accumulated rain, surface bulk density, saturated hydraulic conductivity and soil penetration resistance at the 1.3 cm depth. The best indicators of critical shear stress were accumulated rainfall, soil penetration resistance at 1.3 cm and saturated hydraulic conductivity. Because these erosion parameters had intercepts that were dependent upon the soil series, prediction of changes in soil erosion with time following tillage will be soil-specific.

Infrared absorption has been used to determine the crystal-field levels of the 2 F 7/2 excited multiplet of trivalent cerium doped into scheelite structure LiYF 4 single crystals. A crystal-field analysis well accounts for a total of six experimentally observed energy levels and the ground state g -values as previously determined by electron paramagnetic resonance, whilst intensity simulations confirm the experimentally assigned level symmetries. Temperature dependent spectral line broadening measurements highlight the importance of coupling to low frequency phonon modes of the YF 8 tetrahedron.

A red eye is a common presenting complaint in the primary care setting. Redness of the eye indicates the presence of ocular inflammation, and most commonly represents benign conditions that can be readily treated by the primary care provider. However, there are emergent conditions that can present as a red eye. Primary care providers must readily recognize the danger signs that indicate these more serious ophthalmologic conditions that warrant immediate referral to an ophthalmologist.

This paper presents a Streamline-Upwind Petrov–Galerkin (SUPG) reduced order model (ROM) based on proper orthogonal decomposition (POD). This ROM is investigated theoretically and numerically for convection-dominated convection–diffusion–reaction problems. The SUPG finite element method was used on realistic meshes for computing the snapshots, leading to some noise in the POD data. Numerical analysis is used to propose the scaling of the stabilization parameter for the SUPG-ROM. Two approaches are used: One based on the underlying finite element discretization and the other one based on the POD truncation. The resulting SUPG-ROMs and the standard Galerkin ROM (G-ROM) are studied numerically. For many settings, the results obtained with the SUPG-ROMs are more accurate. Finally, one of the choices for the stabilization parameter is recommended.

The investigation of non-reciprocal behavior of optical beams in a rotating reference frame was the main motivation of the historic tabletop experiment of George Sagnac. His ground-breaking experiment was extended to a very large installation more than a decade later, which was sensitive enough to allow Michelson, Pearson and Gale to resolve the rotation rate of the Earth by an optical interferometer. With the advent of lasers in the early sixties of the last century, rotating laser cavities with a ring structure demonstrated superior performance and very soon matured to a point where mechanical gyroscopes were quickly superseded by laser gyroscopes in aircraft navigation. When vastly upscaled ring lasers were taken back to the laboratory at the end of the 20th century, the goal of applying the Sagnac effect to geodesy for the monitoring of tiny variations of Earth's rotation was the main motivation. The large-ring laser G, which is the most stable instrument out of a series of instruments built by the New Zealand–German collaboration, routinely resolves the rotation rate of the Earth to better than eight orders of magnitude. Since G is directly referenced to the Earth rotation axis, the effect of diurnal polar motion, the Chandler and the Annual wobbles as well as tilts from the solid Earth tides can be found in the interferogram obtained from the ring laser. G has also demonstrated high sensitivity to rotations associated with seismic events. The toroidal eigenmodes of the Earth when they are excited by large earthquakes have been resolved. A surprisingly large amplitude has been measured for Love wave signals contained in the microseismic background signal. This paper summarizes the recent development of highly sensitive large Sagnac gyroscopes, and presents unique results from the measurements of rotations of the earth.

Despite their wide spread use, nearest neighbour density estimators have two fundamental limitations: O ( n 2 ) time complexity and O(n) space complexity. Both limitations constrain nearest neighbour density estimators to small data sets only. Recent progress using indexing schemes has improved to near linear time complexity only. We propose a new approach, called LiNearN for Linear time Nearest Neighbour algorithm, that yields the first nearest neighbour density estimator having O(n) time complexity and constant space complexity, as far as we know. This is achieved without using any indexing scheme because LiNearN uses a subsampling approach for which the subsample values are significantly less than the data size. Like existing density estimators, our asymptotic analysis reveals that the new density estimator has a parameter to trade off between bias and variance. We show that algorithms based on the new nearest neighbour density estimator can easily scale up to data sets with millions of instances in anomaly detection and clustering tasks.

Purpose Cytomegalovirus (CMV) infection can lead to devastating sequelae post heart transplant (HTx), such as organ invasive disease, rejection and coronary allograft vasculopathy. CMV naive HTx patients (pts) who receive organs from CMV positive donors are at very high risk for CMV-related complications. The standard prophylaxis is renally-dosed valganciclovir (VAL) for 12 months, but this one-size-fits-all approach may lead to inadequate serum ganciclovir (GCV) levels, predisposing the pts to VAL resistance. Methods We conducted a retrospective chart review of HTx pts who were CMV recipient negative/donor positive from 12/15-9/18. We started using serum trough GCV levels to guide VAL dosing in 6/17, aiming for trough level of 0.35-0.7 mcg/mL. Pts followed before protocol implementation were in group A and pts who had GCV levels drawn proactively any time during their first year post HTx were in group B. GCV trough levels were checked at 2 weeks, 3 and 6 months, as well as 2 weeks after GCV dose adjustment. CMV viremia was defined as ≥ 137 IU/mL. Results This retrospective study included 29 pts (5 women, mean age 56.3±12.4 years). Group A had 8 pts and group B had 21 pts. 5 pts in group A developed CMV viremia, and 3 developed VAL resistance, requiring treatment with cidofovir or foscarnet. For group B pts, GCV levels ranged from 0.1 to 1.9 mcg/mL. 10 pts achieved therapeutic GCV levels on standard VAL dosing. The other pts required VAL dosing adjustments in increments of 450 mg (maximum 1350 mg/day). 5 pts with levels higher than 0.9 mcg/mL developed leukopenia and VAL dose was adjusted. 3 group B pts developed CMV viremia prior to establishing goal GCV trough levels but none developed CMV resistance. At the end of year 1, CMV IgG was tested, and VAL continued until seroconversion occurred. One pt who remained CMV IgG negative developed viremia when VAL was inadvertently discontinued at 1 year. Conclusion Given the increasing frequency of CMV resistance in HTx pts, we began using trough GCV level-guided VAL dosing instead of standard dosing in 6/17. Our initial experience showed 3/8 seronegative pts developed VAL resistance using standard dosing, whereas 0/21 pts developed VAL resistance using GCV level to adjust VAL dosing. These encouraging findings will warrant a larger experience for confirmation.

Background Inadequate anti–factor Xa levels and increased venous thromboembolic events occur in trauma patients receiving standard prophylactic enoxaparin dosing. The aim of this study was to test the hypothesis that higher dosing (40 mg twice daily) would improve peak anti-Xa levels and decrease venous thromboembolism. Methods A retrospective review was performed of trauma patients who received prophylactic enoxaparin and peak anti-Xa levels over 27 months. Patients were divided on the basis of dose: group A received 30 mg twice daily, and group B received 40 mg twice daily. Demographics and rates of venous thromboembolism were compared between dose groups and patients with inadequate or adequate anti-Xa levels. Results One hundred twenty-four patients were included, 90 in group A and 34 in group B. Demographics were similar, except that patients in group B had a higher mean body weight. Despite this, only 9% of group B patients had inadequate anti-Xa levels, compared with 33% of those in group A ( P = .01). Imaging studies were available in 69 patients and revealed 8 venous thromboembolic events ( P = NS, group A vs group B) with significantly more venous thromboembolic events occurring in patients with low anti-Xa levels ( P = .02). Conclusions Although higher dosing of enoxaparin led to improved anti-Xa levels, this did not equate to a statistical decrease in venous thromboembolism.