135 research outputs found

    Assessment of radar resolution requirements for soil moisture estimation from simulated satellite imagery

    Get PDF
    Radar simulations were performed at five-day intervals over a twenty-day period and used to estimate soil moisture from a generalized algorithm requiring only received power and the mean elevation of a test site near Lawrence, Kansas. The results demonstrate that the soil moisture of about 90% of the 20-m by 20-m pixel elements can be predicted with an accuracy of + or - 20% of field capacity within relatively flat agricultural portions of the test site. Radar resolutions of 93 m by 100 m with 23 looks or coarser gave the best results, largely because of the effects of signal fading. For the distribution of land cover categories, soils, and elevation in the test site, very coarse radar resolutions of 1 km by 1 km and 2.6 km by 3.1 km gave the best results for wet moisture conditions while a finer resolution of 93 m by 100 m was found to yield superior results for dry to moist soil conditions

    A simulation study of scene confusion factors in sensing soil moisture from orbital radar

    Get PDF
    Simulated C-band radar imagery for a 124-km by 108-km test site in eastern Kansas is used to classify soil moisture. Simulated radar resolutions are 100 m by 100 m, 1 km by 1km, and 3 km by 3 km. Distributions of actual near-surface soil moisture are established daily for a 23-day accounting period using a water budget model. Within the 23-day period, three orbital radar overpasses are simulated roughly corresponding to generally moist, wet, and dry soil moisture conditions. The radar simulations are performed by a target/sensor interaction model dependent upon a terrain model, land-use classification, and near-surface soil moisture distribution. The accuracy of soil-moisture classification is evaluated for each single-date radar observation and also for multi-date detection of relative soil moisture change. In general, the results for single-date moisture detection show that 70% to 90% of cropland can be correctly classified to within +/- 20% of the true percent of field capacity. For a given radar resolution, the expected classification accuracy is shown to be dependent upon both the general soil moisture condition and also the geographical distribution of land-use and topographic relief. An analysis of cropland, urban, pasture/rangeland, and woodland subregions within the test site indicates that multi-temporal detection of relative soil moisture change is least sensitive to classification error resulting from scene complexity and topographic effects

    Drosophila Adducin facilitates phase separation and function of a conserved spindle orientation complex

    Get PDF
    Asymmetric cell division (ACD) allows stem cells to generate differentiating progeny while simultaneously maintaining their own pluripotent state. ACD involves coupling mitotic spindle orientation with cortical polarity cues to direct unequal segregation of cell fate determinants. In Drosophila neural stem cells (neuroblasts; NBs), spindles orient along an apical-basal polarity axis through a conserved complex of Partner of Inscuteable (Pins; human LGN) and Mushroom body defect (Mud; human NuMA). While many details of its function are well known, the molecular mechanics that drive assembly of the cortical Pins/Mud complex remain unclear, particularly with respect to the mutually exclusive Pins complex formed with the apical scaffold protein Inscuteable (Insc). Here we identify Hu li tai shao (Hts; human Adducin) as a direct Mud-binding protein, using an aldolase fold within its head domain (HtsHEAD) to bind a short Mud coiled-coil domain (MudCC) that is adjacent to the Pins-binding domain (MudPBD). Hts is expressed throughout the larval central brain and apically polarizes in mitotic NBs where it is required for Mud-dependent spindle orientation. In vitro analyses reveal that Pins undergoes liquid-liquid phase separation with Mud, but not with Insc, suggesting a potential molecular basis for differential assembly mechanics between these two competing apical protein complexes. Furthermore, we find that Hts binds an intact Pins/Mud complex, reduces the concentration threshold for its phase separation, and alters the liquid-like property of the resulting phase separated droplets. Domain mapping and mutational analyses implicate critical roles for both multivalent interactions (via MudCC oligomerization) and protein disorder (via an intrinsically disordered region in Hts; HtsIDR) in phase separation of the Hts/Mud/Pins complex. Our study identifies a new component of the spindle positioning machinery in NBs and suggests that phase separation of specific protein complexes might regulate ordered assembly within the apical domain to ensure proper signaling output

    Does tenure matter for occupant experiences of low-energy housing?

    Get PDF
    International policy settings are looking toward low-energy and near zero-energy homes as a solution to address environmental impacts, particularly anthropogenic climate change. There is increasing research evaluating sus-tainable housing developments from a technical and occupant perspective. One of the key determinants of household energy use is tenure. However, there is limited research which has looked at if tenure impacts on how oc-cupants experience low-energy homes. This paper contributes to the litera-ture by exploring three low-energy housing developments and exploring the role of tenure in relation to how the households experience the dwellings. The case studies demonstrate that social housing tenants have frustrations with a lack of control over what they could, or could not, do to their low-energy dwellings, in comparison to owner-occupier housing

    Egg production and larval rearing of orange-spotted grouper (Epinephelus coioides) using reared broodstocks in Hormozgan Province, Iran

    Get PDF
    Egg production of cultivated broodstocks of orange-spotted grouper, Epinephelus coioides and larvae rearing were surveyed in Iran from 2008 to 2012. Broodstocks were obtained by rearing of 7 wild juveniles (587.57 ± 132.63 g body weight) which were caught from the north of Persian Gulf in October 2008 and reared to December 2012. Captured juvenile fishes were fed using defrosted trash fish at a rate of 4-6 percent of body weight per day. Four-year-old fishes spawned spontaneously, when average weight of females and males were about 7020 ± 1277 g and 5128 ± 253g respectively. Effects of four temperature ranges (23-24, 26-27, 28-29 and 31-32 °C) and three tank size ( 40L, 300L and 2400L) on hatching and survival rates were examined. Eggs were stocked as a density of 25 Eggs L^-1. Effects of tank size on hatching rate and survival of larvae were assessed at 1, 5, 10, 20 and 30 days after hatching (DAH). The optimal temperature range for hatching was 28-29°C. No difference was observed among hatching rates of fish within the various tank sizes. Survival rates of larvae in 2400L fiber glass tanks until 30 days after hatching were significantly higher than the other tanks. Results indicate this species can be reproduced and reared in large numbers under normal rearing conditions and carefully controlled temperature

    A Survey of Methods for Volumetric Scene Reconstruction from Photographs

    Get PDF
    Scene reconstruction, the task of generating a 3D model of a scene given multiple 2D photographs taken of the scene, is an old and difficult problem in computer vision. Since its introduction, scene reconstruction has found application in many fields, including robotics, virtual reality, and entertainment. Volumetric models are a natural choice for scene reconstruction. Three broad classes of volumetric reconstruction techniques have been developed based on geometric intersections, color consistency, and pair-wise matching. Some of these techniques have spawned a number of variations and undergone considerable refinement. This paper is a survey of techniques for volumetric scene reconstruction

    Screen-detected vs clinical breast cancer: the advantage in the relative risk of lymph node metastases decreases with increasing tumour size

    Get PDF
    Screen-detected (SD) breast cancers are smaller and biologically more indolent than clinically presenting cancers. An often debated question is: if left undiagnosed during their preclinical phase, would they become more aggressive or would they only increase in size? This study considered a registry-based series (1988–1999) of 3329 unifocal, pT1a-pT3 breast cancer cases aged 50–70 years, of which 994 were SD cases and 2335 clinical cases. The rationale was that (1) the average risk of lymph node involvement (N+) is lower for SD cases, (2) nodal status is the product of biological aggressiveness and chronological age of the disease, (3) for any breast cancer, tumour size is an indicator of chronological age, and (4) for SD cases, tumour size is specifically an indicator of the duration of the preclinical phase, that is, an inverse indicator of lead time. The hypothesis was that the relative protection of SD cases from the risk of N+ and, thus, their relative biological indolence decrease with increasing tumour size. The odds ratio (OR) estimate of the risk of N+ was obtained from a multiple logistic regression model that included terms for detection modality, tumour size category, patient age, histological type, and number of lymph nodes recovered. A term for the detection modality-by-tumour size category interaction was entered, and the OR for the main effect of detection by screening vs clinical diagnosis was calculated. This increased linearly from 0.05 (95% confidence interval: 0.01–0.39) in the 2–7 mm size category to 0.95 (0.64–1.40) in the 18–22 mm category. This trend is compatible with the view that biological aggressiveness of breast cancer increases during the preclinical phase

    Mast cells and eosinophils in invasive breast carcinoma

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Inflammatory cells in the tumour stroma has gained increasing interest recently. Thus, we aimed to study the frequency and prognostic impact of stromal mast cells and tumour infiltrating eosinophils in invasive breast carcinomas.</p> <p>Methods</p> <p>Tissue microarrays containing 234 cases of invasive breast cancer were prepared and analysed for the presence of stromal mast cells and eosinophils. Tumour infiltrating eosinophils were counted on hematoxylin-eosin slides. Immunostaining for tryptase was done and the total number of mast cells were counted and correlated to the proliferation marker Ki 67, positivity for estrogen and progesterone receptors, clinical parameters and clinical outcome.</p> <p>Results</p> <p>Stromal mast cells were found to correlate to low grade tumours and estrogen receptor positivity. There was a total lack of eosinophils in breast cancer tumours.</p> <p>Conclusion</p> <p>A high number of mast cells in the tumours correlated to low-grade tumours and estrogen receptor positivity. Eosinophils are not tumour infiltrating in breast cancers.</p

    Monitoring of Cochlodinium sp for shrimp farms in Hormozgan Province

    Get PDF
    The Blooming due to the some species of phytoplanktons especially Dynoflagellates has made some problems for water ecosystems and aquaculture. In this study, the density of phytoplanktons specially Cochlodinium sp. and also environmental factors such as temperature, pH, dissolved Oxygen, and transparency were recorded two weekly in 18 stations of Hormozgan province, Iran in order to monitoring of the possibility of phytoplankton blooming. During six months monitoring, the target phytoplankton, Cochlodinium sp was not observed in shrimp farms. But, other phytoplanktons and zooplanktons were observed as follow: 13 genus of phytoplankton and six genuses of zooplanktons has found in ponds, main water channel and sea. The diatoms with 10 genuses had the highest abundance and Dynoflagellates with 3 genuses had the lowest abundance and blue-green phytoplankton with one genus was in lowest group. Totally, diatoms with 77%, Dynoflagellate with 15% and blue-green alga with 8% abundance were the main populations of planktons in the studied area
    • …
    corecore