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AIM: To evaluate the fractal feature of the retinal vasculature of normal eyes on a stereographic projected and montaged ultra-wide field (UWF) fluorescein angiography (FA). METHODS: Prospective, observational, cross-sectional study. Totally 59 eyes of 31 normal subjects were imaged using the Optos 200Tx. Images obtained at different gaze angles stereographically projected and montaged. The early-phase UWF FA frames were processed to segment the retinal vasculature and the results were exported as binary masks. The fractal dimension (FD) was calculated using the box-counting method. RESULTS: The global FD for the entire retina was 1.6±0.04, with no difference between males and females (1.59±0.04 vs 1.61±0.04, P=0.084) or between right and left eyes (1.6±0.04 vs 1.6±0.05, P=0.61). FD was non-uniformly distributed among four quadrants (P0.05). CONCLUSION: Fractal geometry is non-uniformly distributed across the retina in normal eyes and decreases from the fovea to the far-periphery. Subjects with an older age tend to have a smaller FD, however, the FD in the far-periphery does not appear to be influenced by age.

Abstract Alpine treelines are expected to shift upward due to recent climate change. However, interpretation of changes in montane systems has been problematic because effects of climate change are frequently confounded with those of land use changes. The eastern Himalaya, particularly Langtang National Park, Central Nepal, has been relatively undisturbed for centuries and thus presents an opportunity for studying climate change impacts on alpine treeline uncontaminated by potential confounding factors. We studied two dominant species, Abies spectabilis (AS) and Rhododendron campanulatum (RC), above and below the treeline on two mountains. We constructed 13 transects, each spanning up to 400 m in elevation, in which we recorded height and state (dead or alive) of all trees, as well as slope, aspect, canopy density, and measures of anthropogenic and animal disturbance. All size classes of RC plants had lower mortality above treeline than below it, and young RC plants (

Abstract Background Low‐molecular‐weight heparin has been the preferred treatment of cancer‐associated thrombosis (CAT); however, emerging data support the use of direct oral anticoagulants (DOACs). Objectives The Memorial Sloan Kettering Cancer Center Clinical Pathway has served as the institutional guideline for the use of rivaroxaban to treat CAT since 2014. Key elements are to recommend against use of a DOAC in patients with active gastrointestinal (GI) or genitourinary tract lesions, and a prespecified dose reduction in the elderly (75+ years old). We present our institutional experience for treatment of CAT. Methods From January 2014 through September 2016, 1072 patients began rivaroxaban treatment for CAT; 91.9% had a solid tumor, 8.1% had hematologic malignancies, and 75% of patients with solid tumors had metastatic disease. All patients with CAT treated with rivaroxaban were included in this analysis, regardless of adherence to the Clinical Pathway. Results The 6‐month cumulative incidence of recurrent venous thromboembolism and major bleeding were 4.2% (95% confidence interval [CI], 2.7%‐5.7%) and 2.2% (95% CI, 1.1%‐3.2%), respectively. The incidence of clinically relevant non–major bleeding leading to discontinuation of rivaroxaban for at least 7 days was 5.5% (95% CI, 3.7%‐7.1%), and 73.3% of major bleeds occurred in the GI tract. The 6‐month cumulative mortality rate was 22.2% (95% CI, 19.4%‐24.9%). The elderly had similar rates of recurrent thrombosis and bleeding as those aged under 75 years. Conclusion Our institutional experience suggests that in appropriately selected patients, rivaroxaban may be used for treatment of CAT with promising safety and efficacy.

Current testing methods are capable of measuring strain near the surface on structural parts, for example by using strain gauges. However, stress peaks often occur within the material and can only be approximated. An alternative strain measurement incorporates fibre-optical strain sensors (Fiber Bragg Gratings, FBG) which are able to determine strains within the material. The principle has already been verified by using embedded FBGs in tensile specimens. The transition area between fibre and aluminium, however, is not yet properly investigated. Therefore, strains in tensile specimens containing FBGs were measured by neutron diffraction in gauge volumes of two different sizes around the Bragg grating. As a result, it is possible to identify and decouple elastic and plastic strains affecting the FBGs and to transfer the findings into a fully descriptive FE-model of the strain transition area.We thus accomplished closing the gap between the external load and internal straining obtained from cast-in FBG and generating valuable information about the mechanisms within the strain transition area.It was found that the porosity within the casting has a significant impact on the stiffness of the tensile specimen, the generation of excess microscopic tensions and thus the formation of permanent plastic strains, which are well recognized by the FBG. The knowledge that FBG as internal strain sensors function just as well as common external strain sensors will now allow for the application of FBG in actual structural parts and measurements under real load conditions. In the future, applications for long-term monitoring of cast parts will also be enabled and are currently under development.

Current management of age-related macular degeneration (AMD) is directed at intravitreal injection of vascular endothelial growth factor (VEGF) inhibitors for the treatment of wet AMD and supplementation with oral antioxidants for the treatment of dry AMD. In this article, we will review recent clinical trials for the treatment of dry and wet AMD.

Let $X$ be a compact 4-manifold with boundary. We study the space of hyperkähler triples $\unicode[STIX]{x1D714}_{1},\unicode[STIX]{x1D714}_{2},\unicode[STIX]{x1D714}_{3}$ on $X$ , modulo diffeomorphisms which are the identity on the boundary. We prove that this moduli space is a smooth infinite-dimensional manifold and describe the tangent space in terms of triples of closed anti-self-dual 2-forms. We also explore the corresponding boundary value problem: a hyperkähler triple restricts to a closed framing of the bundle of 2-forms on the boundary; we identify the infinitesimal deformations of this closed framing that can be filled in to hyperkähler deformations of the original triple. Finally we study explicit examples coming from gravitational instantons with isometric actions of $\text{SU}(2)$ .

The UC Sierra Foothill Research and Extension Center (SFREC) is located in the heart of typical California blue oak and live oak woodlands within metavolcanic terrain of the Sierra Nevada foothills. These types of woodlands often exist at the interface between urban, wild and agricultural lands and are used extensively for livestock grazing, wildlife habitat and surface water supply. Soil surveys for this region and within SFREC depict relatively few soil types compared to areas that support more-intensive agricultural land uses. Despite this inferred homogeneity, our study showed that the biogeochemical and physical properties of soils vary sharply over short distances of less than 10 feet and also experience changes by season and as a result of storm events. An understanding of soil variability in this setting is important to assess rangeland productivity, perennial grass and oak restoration potential, carbon sequestration, stream flow generation and stream water chemistry.

Monitoring water quality is a major issue on California's rangeland watersheds, and there is limited published data to guide these efforts. We used stream-flow and water-quality data from experimental rangeland watersheds to demonstrate the temporal variability of water quality at the storm, season and annual time scales. The timing and frequency of water sampling from the storm to the annual time scale play an extremely significant role in water-quality monitoring. Our studies conducted in Northern California suggest that a minimum sampling strategy should include sampling before, during and after storms. Samples must be collected over a period of several years to account for variability among years.

The association between dermatomyositis and celiac disease in children has been well documented. In the adult population, however, the association has not been clearly established. A rare case of concomitant dermatomyositis and celiac disease in a 40-year-old woman is presented. After having been diagnosed with dermatomyositis and iron deficiency anemia, this patient was referred to the gastroenterology clinic to exclude a gastrointestinal malignancy. Blood tests revealed various vitamin deficiencies consistent with malabsorption. The results of gastroscopy with duodenal biopsy were consistent with celiac disease. After she was put on a strict gluten-free diet, both nutritional deficiencies and the dermatomyositis resolved. The patient’s human leukocyte antigen haplotype study was positive for DR3 and DQ2, which have been shown to be associated with both juvenile dermatomyositis and celiac disease. It is suggested that patients with newly diagnosed dermatomyositis be investigated for concomitant celiac disease even in the absence of gastrointestinal symptoms.

Respirable dust (RD), defined as particles smaller than 4 µm diameter, was collected at the implement from 29 farming operations performed for furrow-irrigated tomato, corn, and wheat crop production over a 2-year period. Land preparation, such as land planing, ripping, plowing, and disking, produced significantly higher concentrations of RD than most other cultivation operations. Land preparation accounted for 67% of all farming operations, but produced 82% of the RD. The number of operations and the timing of land preparation were responsible for the difference in RD concentrations among the seven 2-year crop rotations. Of the studied crops, tomato and corn were the most intensively cultivated and yielded the highest RD amounts. Soil moisture was an important environmental variable that influenced the amount of dust and the variability in dust concentration from sample to sample. Among the cropping systems studied, those that required more tillage or land preparation to be performed when the soil was driest produced the most RD.

Measurements before and after removal of oaks from 14% of a 250-acre watershed indicated small but not statistically significant increases in the runoff/rainfall ratio and no change in nutrient or sediment removal. Careful, selective oak removal appeared to have no harmful effect on water quality.