Measuring the Reflection Matrix of a Rough Surface

Phase modulation methods for imaging around corners with reflectively scattered light required illumination of the occluded scene with a light source either in the scene or with direct line of sight to the scene. The RM (reflection matrix) allows control and refocusing of light after reflection, which could provide a means of illuminating an occluded scene without access or line of sight. Two optical arrangements, one focal-plane, the other an imaging system, were used to measure the RM of five different rough-surface reflectors. Intensity enhancement values of up to 24 were achieved. Surface roughness, correlation length, and slope were examined for their effect on enhancement. Diffraction-based simulations were used to corroborate experimental results

Reflective Inverse Diffusion

Phase front modulation was previously used to refocus light after transmission through scattering media. This process has been adapted here to work in reflection. A liquid crystal spatial light modulator is used to conjugate the phase scattering properties of diffuse reflectors to produce a converging phase front just after reflection. The resultant focused spot had intensity enhancement values between 13 and 122 depending on the type of reflector. The intensity enhancement of more specular materials was greater in the specular region, while diffuse reflector materials achieved a greater enhancement in non-specular regions, facilitating non-mechanical steering of the focused spot. Scalar wave optics modeling corroborates the experimental results

Preliminary documentation of coseismic ground failure triggered by the February 6, 2023 Türkiye earthquake sequence

The devastating Kahramanmaraş earthquake sequence occurred on February 6, 2023. Two main events, Mw 7.8 and Mw 7.5 occurred 9 hours apart, affected 11 cities in Turkey, and subjected an area of ∼90,000 km2 to shaking levels known to trigger landslides (peak ground acceleration > 0.08 g). Extensive landsliding was expected given the hilly terrain affected by this significant ground shaking—about 15% of the topography is steeper than 20°—but was not initially apparent in early satellite imagery, mostly because of obscuring snow that fell just after the earthquakes. However, after a more detailed investigation using high-resolution satellite images, aerial photos, and a field survey, we confirmed that this earthquake sequence did, indeed, trigger numerous landslides. In this study, we present those findings and provide a preliminary characterization of the spatial distribution, general characteristics, and dominant types of landslides and hillslope deformation triggered by the earthquake sequence. We mapped 3673 coseismic landslides, mostly concentrated in the northern half of the impacted area. Rock falls are the most abundant landslide type, but bedrock rotational landslides, translational slides and lateral spreads are also numerous. Surface rupture through mountainous terrain caused several large, and in some cases fatal, landslides. Incipient landslides and ground cracks are also widespread, especially in the north. Lithology, spatial variability of ground shaking, and topographic relief appear to be the main variables controlling the spatial distribution of coseismic landslides. There are few detailed studies of earthquake-triggered landslides in arid and semi-arid regions such as this one, nor for such complex earthquake sequences. Therefore, this contribution provides valuable information for future hazard and modeling efforts in arid and semi-arid regions

Past and recent effects of livestock activity on the genetic diversity and population structure of native guanaco populations of arid patagonia

Extensive livestock production and urbanization entail modifications of natural landscapes, including installation of fences, development of agriculture, urbanization of natural areas, and construction of roads and infrastructure that, together, impact native fauna. Here, we evaluate the diversity and genetic structure of endemic guanacos (Lama guanicoe) of the Monte and Patagonian Steppe of central Argentina, which have been reduced and displaced by sheep ranching and other impacts of human activities. Analyses of genetic variation of microsatellite loci and d-loop revealed high levels of genetic variation and latitudinal segregation of mitochondrial haplotypes. There were indications of at least two historical populations in the Monte and the Patagonian Steppe based on shared haplotypes and shared demographic history among localities. Currently, guanacos are structured into three groups that were probably reconnected relatively recently, possibly facilitated by a reduction of sheep and livestock in recent decades and a recovery of the guanaco populations. These results provide evidence of the genetic effects of livestock activity and urbanization on wild herbivore populations, which were possibly exacerbated by an arid environment with limited productive areas. The results highlight the importance of enacting conservation management plans to ensure the persistence of ancestral and ecologically functional populations of guanacos.Fil: Mesas, Andrés. Universidad del Bio Bio; ChileFil: Baldi, Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico para el Estudio de los Ecosistemas Continentales; Argentina. South American Camelids Specialist Group; Chile. Wildlife Conservation Society; ArgentinaFil: González, Benito A.. South American Camelids Specialist Group; Chile. Universidad de Chile; ChileFil: Burgi, Maria Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico para el Estudio de los Ecosistemas Continentales; Argentina. South American Camelids Specialist Group; Chile. Wildlife Conservation Society; ArgentinaFil: Chávez, Alexandra. Universidad del Bio Bio; ChileFil: Johnson, Warren E.. Smithsonian Conservation Biology Institute; Estados UnidosFil: Marín, Juan C.. Universidad del Bio Bio; Chil

Bicycle-Safe Grate Inlets Study Volume 1 - Hydraulic and Safety Characteristics of Selected Grate Inlets on Continuous Grades

PO-5-3-0166Eleven drain inlet grates were tested to evaluate their safety characteristics for bicycle as well as pedestrian traffic. Four of the grates that rated highest were selected for hydraulic testing. Three other grates with designs and bar spacings similar to grates proven safe were also selected for hydraulic testing. Test results show that two of the grate designs (a cast and a steel fabricated grate) are nearly as hydraulically efficient as the parallel bar grate and considerably more efficient than the other grate designs tested. One other design (a steel fabricated grate) shows high hydraulic efficiencies at longitudinal slopes up to 6 percent. These three grate designs are recommended for additional testing. A grate's ability to handle debris without clogging was shown to be most dependent on the spacing of its longitudinal bars

Modelling and simulating change in reforesting mountain landscapes using a social-ecological framework

Natural reforestation of European mountain landscapes raises major environmental and societal issues. With local stakeholders in the Pyrenees National Park area (France), we studied agricultural landscape colonisation by ash (Fraxinus excelsior) to enlighten its impacts on biodiversity and other landscape functions of importance for the valley socio-economics. The study comprised an integrated assessment of land-use and land-cover change (LUCC) since the 1950s, and a scenario analysis of alternative future policy. We combined knowledge and methods from landscape ecology, land change and agricultural sciences, and a set of coordinated field studies to capture interactions and feedback in the local landscape/land-use system. Our results elicited the hierarchically-nested relationships between social and ecological processes. Agricultural change played a preeminent role in the spatial and temporal patterns of LUCC. Landscape colonisation by ash at the parcel level of organisation was merely controlled by grassland management, and in fact depended on the farmer's land management at the whole-farm level. LUCC patterns at the landscape level depended to a great extent on interactions between farm household behaviours and the spatial arrangement of landholdings within the landscape mosaic. Our results stressed the need to represent the local SES function at a fine scale to adequately capture scenarios of change in landscape functions. These findings orientated our modelling choices in the building an agent-based model for LUCC simulation (SMASH - Spatialized Multi-Agent System of landscape colonization by ASH). We discuss our method and results with reference to topical issues in interdisciplinary research into the sustainability of multifunctional landscapes

Consensus guideline for the diagnosis and treatment of tetrahydrobiopterin (BH4) deficiencies

Background: Tetrahydrobiopterin (BH4) deficiencies comprise a group of six rare neurometabolic disorders characterized by insufficient synthesis of the monoamine neurotransmitters dopamine and serotonin due to a disturbance of BH4 biosynthesis or recycling. Hyperphenylalaninemia (HPA) is the first diagnostic hallmark for most BH4 deficiencies, apart from autosomal dominant guanosine triphosphate cyclohydrolase I deficiency and sepiapterin reductase deficiency. Early supplementation of neurotransmitter precursors and where appropriate, treatment of HPA results in significant improvement of motor and cognitive function. Management approaches differ across the world and therefore these guidelines have been developed aiming to harmonize and optimize patient care. Representatives of the International Working Group on Neurotransmitter related Disorders (iNTD) developed the guidelines according to the SIGN (Scottish Intercollegiate Guidelines Network) methodology by evaluating all available evidence for the diagnosis and treatment of BH4 deficiencies. Conclusion: Although the total body of evidence in the literature was mainly rated as low or very low, these consensus guidelines will help to harmonize clinical practice and to standardize and improve care for BH4 deficient patients

Dapagliflozin: a sodium glucose cotransporter 2 inhibitor in development for type 2 diabetes

Type 2 diabetes mellitus (T2DM) is a growing worldwide epidemic. Patients face lifelong therapy to control hyperglycemia and prevent the associated complications. There are many medications, with varying mechanisms, available for the treatment of T2DM, but almost all target the declining insulin sensitivity and secretion that are associated with disease progression. Medications with such insulin-dependent mechanisms of action often lose efficacy over time, and there is increasing interest in the development of new antidiabetes medications that are not dependent upon insulin. One such approach is through the inhibition of renal glucose reuptake. Dapagliflozin, the first of a class of selective sodium glucose cotransporter 2 inhibitors, reduces renal glucose reabsorption and is currently under development for the treatment of T2DM. Here, we review the literature relating to the preclinical and clinical development of dapagliflozin