Physician attitude, awareness, and knowledge regarding guidelines for transcranial Doppler screening in sickle cell disease.

ObjectiveWe explored factors that may influence physician adherence to transcranial Doppler (TCD) screening guidelines among children with sickle cell disease.MethodsPediatric hematologists, neurologists, and primary care physicians (n = 706) responded to a mailed survey in May 2012 exploring factors hypothesized to influence physician adherence to TCD screening guidelines: physician (internal) barriers and physician-perceived external barriers. Responses were compared by specialty using chi-square tests.ResultsAmong 276 physicians (44%), 141 currently treated children with sickle cell disease; 72% recommend screening. Most primary care physicians (66%) did not feel well informed regarding TCD guidelines, in contrast to neurologists (25%) and hematologists (6%, P < .0001). Proportion of correct answers on knowledge questions was low (13%-35%). Distance to a vascular laboratory and low patient adherence were external barriers to receipt of TCD screening.ConclusionsAdditional research regarding physicians' lack of self-efficacy and knowledge of recommendations could help clarify their role in recommendation of TCD screening

Missed Opportunities for Transcranial Doppler Screening Among Children With Sickle Cell Disease.

Transcranial Doppler (TCD) screening rates remain low among children with sickle cell disease (SCD). We assessed TCD screening rates and missed opportunities for TCD screening. Children 2 to 16 years old with SCD enrolled in Michigan Medicaid for ≥1 year (2007-2011) were identified through newborn screening. Receipt of TCD screening and presence of a missed opportunity (≥1 SCD-related outpatient visit, no TCD screening) were identified through administrative claims. Potential correlates of missed opportunities included SCD-related health services, comorbidities, and demographics. Logistic regression with generalized estimating equations modeled associations between a missed opportunity and correlates. Overall, 353 children contributed 1066 person-years. TCD screening was low yearly (10%-32%); missed opportunities occurred in 73% of the person-years. Increasing age (odds ratio [OR] = 1.11; confidence interval CI = 1.07, 1.15), previous TCD screening (OR = 0.26; CI = 0.16, 0.41), and 4 to 5 (OR = 0.48; CI = 0.26, 0.87) or ≥6 outpatient visits (OR = 0.26; CI = 0.14, 0.49) were associated with a missed opportunity. Reduction of missed opportunities is a potential strategy to increase TCD screening rates

Development and validation of a measure of maladaptive social-evaluative beliefs characteristic of social anxiety disorder in youth: the Report of Youth Social Cognitions (RYSC)

Recent research has started to examine the applicability of influential adult models of the maintenance of social anxiety disorder (SAD) to youth. This research is limited by the lack of psychometrically validated measures of underlying constructs that are developmentally appropriate for youth. One key construct in adult models of SAD is maladaptive social-evaluative beliefs. The current study aimed to develop and validate a measure of these beliefs in youth, known as the Report of Youth Social Cognitions (RYSC). The RYSC was developed with a clinical sample of youth with anxiety disorders (N = 180) and cross-validated in a community sample of youth (N = 305). In the clinical sample, the RYSC exhibited a three-factor structure (Negative Evaluation, Revealing Self, and Positive Impression factors), good internal consistency, and construct validity. In the community sample, the three-factor structure and the internal consistency of the RYSC were replicated, but the test of construct validity showed that the RYSC had similarly strong associations with social anxiety and depressed affect. The RYSC had good test-retest reliability overall, although the Revealing Self subscale showed lower temporal stability which improved when only older participants were considered (age ≥ 9 years). The RYSC in general was also shown to discriminate between youth with and without SAD although the Revealing Self subscale again performed suboptimally but improved when only older participants were considered. These findings provide psychometric support for the RYSC and justifies its use with youth in research and clinical settings requiring the assessment of maladaptive social-evaluative beliefs

Complex erosional response to uplift and rock strength contrasts in transient river systems crossing an active normal fault revealed by \u3csup\u3e10\u3c/sup\u3eBe and \u3csup\u3e26\u3c/sup\u3eAl cosmogenic nuclide analyses

Understanding the influence of bedrock lithology on the catchment-averaged erosion rates of normal fault-bounded catchments and the effect that different bedrock erodibilties have on the evolution of transient fluvial geomorphology remain major challenges. To investigate this problem, we collected 18 samples for 10Be and 26Al cosmogenic nuclide analysis to determine catchment-averaged erosion rates along the well-constrained Gediz Fault system in western Türkiye, which is experiencing fault-driven river incision owing to a linkage event ~0.8 Ma and has weak rocks overlying strong rocks in the footwall. Combined with existing cosmogenic data, we show that the background rate of erosion of the pre-incision landscape can be constrained as \u3c92 mMyr−1, and erosion rates within the transient reach vary from 16 to 1330 mMyr−1. Erosion rates weakly scale with unit stream power, steepness index and slip rate on the bounding fault, although erosion rates are an order of magnitude lower than slip rates. However, there are no clear relationships between erosion rate and relief or catchment slope. Bedrock strength is assessed using Schmidt hammer rebound and Selby Rock Mass Strength Assessments; despite a 30-fold difference in erodibility, there is no difference in the erosion rate between strong and weak rocks. We argue that, for the Gediz Graben, the strong lithological contrast affects the ability of the river to erode the bed, resulting in a complex erosional response to uplift along the graben boundary fault. Weak covariant trends between erosion rates and various topographic factors potentially result from incomplete sediment mixing or pre-existing topographic inheritance. These findings indicate that the erosional response to uplift along an active normal fault is a complex response to multiple drivers that vary spatially and temporally

Rock strength and structural controls on fluvial erodibility: Implications for drainage divide mobility in a collisional mountain belt

Numerical model simulations and experiments have suggested that when migration of the main drainage divide occurs in a mountain belt, it can lead to the rearrangement of river catchments, rejuvenation of topography, and changes in erosion rates and sediment flux. We assess the progressive mobility of the drainage divide in three lithologically and structurally distinct groups of bedrock in the High Atlas (NW Africa). The geological age of bedrock and its associated tectonic architecture in the mountain belt increases from east to west in the study area, allowing us to track both variations in rock strength and structural configuration which influence drainage mobility during erosion through an exhuming mountain belt. Collection of field derived measurements of rock strength using a Schmidt hammer and computer based extraction of river channel steepness permit estimations of contrasts in fluvial erodibilities of rock types. The resulting difference in fluvial erodibility between the weakest and the strongest lithological unit is up to two orders of magnitude. Published evidence of geomorphic mobility of the drainage divide indicates that such a range in erodibilities in horizontal stratigraphy of the sedimentary cover may lead to changes in erosion rates as rivers erode through strata, leading to drainage divide migration. In contrast, we show that the faulted and folded metamorphic sedimentary rocks in the centre of the mountain belt coincide with a stable drainage divide. Finally, where the strong igneous rocks of the crystalline basement are exposed after erosion of the covering meta-sediments, there is a decrease in fluvial erodibility of up to a factor of three, where the drainage divide is mobile towards the centre of the exposed crystalline basement. The mobility of the drainage divide in response to erosion through rock-types and their structural configuration in a mountain belt has implications for the perception of autogenic dynamism of drainage networks and fluvial erosion in mountain belts, and the interpretation of the geomorphology and downstream stratigraphy

Smart sensors to detect movements of cobbles and large woody debris dams. Insights from lab experiments.

An increase in population pressure and severe storms under climate change have greatly impacted landslide and flood hazards globally. At the same time, recent advances in Wireless Sensor Network (WSN) and Internet of Things (IoT) technologies, microelectronics and machine learning offer new opportunities to effectively monitor stability of boulder and woody debris on landslides and in flood-prone rivers. In this framework, smart sensors embedded in elements within the landslide body and the river catchment can be potentially used for monitoring purposes and for developing early warning systems. This is because they are small, light-weight, and able to collect different environmental data with low battery consumption and communicate to a server through a wireless connection. However, their reliability still needs to be evaluated. As data from field sites could be fragmented, laboratory experiments are essential to validate sensor data and see their potential in a controlled environment. In the present study, dedicated laboratory experiments were designed to assess the ability of a tag equipped with an accelerometer, a gyroscope, and a magnetometer to detect movements in two different settings. In the first experimental campaign, the tag was installed inside a cobble of 10.0 cm diameter within a borehole of 4.0 cm diameter. The experiments consisted in letting the cobble fall on an experimental table composed of an inclined plane of 1.5 m, followed by a horizontal one of 2.0 m. The inclined plane can be tilted at different angles (18˚- 55˚) and different types of movement have been generated by letting the cobble roll, bounce, or slide. Sliding was generated by embedding the cobble within a layer of sand. The position of the cobble travelling down the slope was derived from camera videos by a tracking algorithm developed within the study. In the second experimental campaign, a simplified analogue model of a woody debris dam was built from a single hollowed dowel with a length of 40 cm and a diameter of 3.8 cm. The sensor tag is installed in the woody dowel within a 2.5 cm longitudinal borehole. Two metal rigs are mounted at both sides of the woody dowel to allow different modes of movement. Specifically, the woody dowel is allowed to move either horizontally or vertically within a range of 20-30 mm, whereas it is always free to complete full rotations. The woody dowel is mounted on a frame within a 20 m long and 0.6 m wide flume. In these two experimental settings, combining data from the accelerometer, gyroscope and magnetometer it was possible to detect movements and differentiate between different type of motions both in a woody dowel and in the cobble under different initial conditions. Data were analysed to understand which type of information could be retrieved. This gives important insights for the assessment of the feasibility and effectiveness of the use of smart sensors in the detection of movements in woody logs within dams and boulders embedded in landslides, thus providing indications for the development of early warning systems using this innovative technology