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Crohn's disease is an inflammatory bowel disorder with various extraintestinal manifestations. Vulva is rarely involved in Crohn's disease and occasionally may constitute the only sign of the disease. It is often unrecognized and can be confused with various disorders involving the vulva. Vulval Crohn's disease is often refractory to treatment. We describe a case of 30-year-old female presented with labial swelling, discharging sinuses and knife cut fissures and diagnosed as a case of vulval Crohn's without intestinal involvement, that was managed with oral steroids, sulfasalazine, and metronidazole.

Bullous pemphigoid (BP) is an autoimmune blistering disorder affecting elderly people. It presents as tense blisters on urticarial base and is associated with intense pruritus. It commonly involves lower abdomen, inner or anterior thighs, and flexor forearms. Localized BP limited to certain parts of the body has also been described in literature. Both classical and localized BP is diagnosed based on histopathology and immunofluorescence. Corticosteroids remain the main stay of treatment. Here, we describe a case of BP presenting as malar blistering closely mimicking bullous systemic lupus erythematosus.

Onychomycosis refers to the nondermatophytic and dermatophytic involvement of nails. Literature suggests its increasing prevalence from the younger to the older age group. In addition to the important clinical consequences that the infection holds, it also acts as a reservoir of infection. We, hereby, report a case of a 3-year-old immunocompetent child with single nail onychomycosis due to Aspergillus niger. To the best of our knowledge, this is the youngest reported case of onychomycosis due to A. niger.

The problem of self-replication initiated by John von Neumann has been investigated by many researchers from different perspectives. As a part of our earlier investigation into self-replication through graph reproduction, we introduced a comprehensive graph reproduction system and identified a few graph reproduction models that are self-replicable. This paper addresses the question of whether a combination of more than one non-self-replicable graph reproduction model is selfreplicable or not. A few existing graph reproduction models were combined in two different ways and tested for self-replicability. Our study confirms that non-self-replicable graph reproduction models become self-replicable by combining themselves with other reproduction models. [ABSTRACT FROM AUTHOR]

A study to look at how heat and mass transfer affect unsteady MHD flow across an accelerated plate with changing temperature and mass diffusion in the appearance of a heat source (or sink) through porous medium is presented. Initially the temperature and concentration of the fluid and plate are considered to be same at t' ≤ 0. At t' > 0, an impulsive uniform acceleration A is applied to the plate in a vertical upward direction. The non-dimensionalised governing equations defining the flow problem are solved using Laplace transform approach. Effect of various physical quantities involved in the velocity, concentration, temperature, the rate of heat transfer and also the rate of mass transfer are investigated through graphs and tables and discussed. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Mining & Metallurgy. Section B: Metallurgy is the property of Journal of Mining & Metallurgy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Despite extensive efforts to maximize ground coverage and improve upscaling functions within core validation sites (CVS) of the NASA Soil Moisture Active Passive (SMAP) mission, spatial averages of point-scale soil moisture observations often fail to accurately capture the true average of the reference pixels. Therefore, some level of pixel-scale sampling error from in situ observations must be considered during the validation of SMAP soil moisture retrievals. Here, uncertainties in the SMAP core site average soil moisture (CSASM) due to spatial sampling errors are examined and their impact on CSASM-based SMAP calibration and validation metrics is discussed. The estimated uncertainty (due to spatial sampling limitations) of mean CSASM over time is found to be large, translating into relatively large sampling uncertainty levels for SMAP retrieval bias when calculated against CSASM. As a result, CSASM-based SMAP bias estimates are statistically insignificant at nearly all SMAP CVS. In addition, observations from temporary networks suggest that these (already large) bias uncertainties may be underestimated due to undersampled spatial variability. The unbiased root-mean-square error (ubRMSE) of CSASM is estimated via two approaches: classical sampling theory and triple collocation, both of which suggest that CSASM ubRMSE is generally within the range of 0.01–0.02 m3 m−3. Although limitations in both methods likely lead to underestimation of ubRMSE, the results suggest that CSASM captures the temporal dynamics of the footprint-scale soil moisture relatively well and is thus a reliable reference for SMAP ubRMSE calculations. Therefore, spatial sampling errors are revealed to have very different impacts on efforts to estimate SMAP bias and ubRMSE metrics using CVS data. [ABSTRACT FROM AUTHOR]

This paper proposes a novel active-clamp forward converter (ACFC) with a lossless-snubber on the secondary-side, which combines a resonant capacitor and a clamping diode with an output inductor in parallel. The conventional ACFC achieves zero-voltage-switching on switches of the primary-side during dead time for reducing the switching loss and voltage spike. Unfortunately, on the secondary-side of transformer, the voltage spike damages the free-wheeling diode and rectifier diode due to the reverse recovery current and junction-capacitor of the diode and leakage inductance of the transformer. This paper proposes a lossless-snubber on the secondary-side operation for reducing the voltage spike on the free-wheeling diode and forward-rectifier diode. Therefore, the converter proposed in this paper is suitable for high-output-current applications. Experimental results are shown to verify the analysis and design procedure of the proposed forward converter. [ABSTRACT FROM AUTHOR]

Land surface models (LSMs) have been widely used to provide objective monitoring of soil moisture during drought, but large uncertainties exist because of the different parameterizations in LSMs. This study aims to evaluate the ability to monitor soil moisture drought over three key regions in China by using the Noah LSM from the Global Land Data Assimilation System, version 2 (GLDASv2), and the Community Atmosphere Biosphere Land Exchange (CABLE) model that is currently used at the China Meteorological Administration. The modeled soil moisture drought indices were verified against the standardized precipitation evapotranspiration index (SPEI), which served as a reference drought indicator over northern China (NC), northwestern China (NWC), and southwestern China (SWC) from 1961 to 2010. The results show that the precipitation forcing data that drive both LSMs have high accuracy when compared with local observational data. GLDASv2/Noah outperforms CABLE in capturing soil moisture anomalies and variability, especially in SWC, but both show good correlations with the 3-month SPEI (SPEI3) in NC, NWC, and SWC. The autumn drought of 2002 and spring drought of 2010 were selected for the comparison of the modeled drought categories with the SPEI3 drought category, where GLDASv2/Noah performed slightly better than CABLE. This work demonstrates that the choice of LSM is crucial for monitoring soil moisture drought and that the GLDASv2/Noah LSM can be a good candidate for the development of a new operational drought-monitoring system in China. [ABSTRACT FROM AUTHOR]

The distorted Born approximation (DBA) of volume scattering was previously combined with the numerical solution of Maxwell equations (NMM3D) for rough surfaces to calculate radar backscattering coefficients for the Soil Moisture Active Passive (SMAP) mission. The model results were validated with the Soil Moisture Active Passive Validation Experiment 2012 (SMAPVEX12) data. In this paper we extend the existing model to calculate the bistatic scattering coefficients for each of the three scattering mechanisms: volume, double bounce and surface scattering. Emissivities are calculated by integrating the bistatic scattering coefficients over the hemispherical solid angle. The backscattering coefficients and emissivities calculated using this approach form a consistent model for combined active and passive microwave remote sensing. This has the advantage that the active and passive microwave remote sensing models are founded on the same theoretical basis and hence allow the use of the same physical parameters such as crop density, plant height, stalk orientation, leaf radius, and surface roughness, amongst others. In this paper, this combined active and passive model, DBA/NMM3D, is applied to four vegetation types to calculate both backscattering coefficients and brightness temperature: wheat, winter wheat pasture and canola. This model uses a single-scattering and incoherent vegetation model which is applicable for the vegetation fields studied in this paper but not suitable for vegetation types where collective scattering or multiple scattering effects are important. We demonstrate the use of the DBA/NMM3D for both active and passive using the same input parameters for matching active and passive coincident data. The model results are validated using coincident airborne Passive Active L-band System (PALS) low-altitude radiometer data and Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) data taken during the SMAPVEX12 field campaign. Results show an average root mean squared error (RMSE) of 1.04 dB and 1.21 dB for backscatter at V V and HH, respectively, and 4.65K and 6.44K for brightness temperature at V-pol and H-pol, respectively. The results are comparable to those from the tau-omega model which is commonly used to compute the brightness temperature, though the physical parameters used in this model are different from the empirically adjusted parameters used in the tau-omega model. [ABSTRACT FROM AUTHOR]

Soil hydraulic properties (SHPs) control infiltration and redistribution of moisture in a soil column. The Noah land surface model (LSM) default simulation selects SHPs according to a location's mapped soil texture class. SHPs are instead estimated at seven sites in North America through calibration. A single-objective algorithm minimizes the root-mean-square difference (RMSD) between simulated surface soil moisture and observations from 1) a dense network of in situ probes, 2) Soil Moisture Ocean Salinity (SMOS) satellite retrievals, and 3) SMOS retrievals adjusted such that their mean equals that of the in situ network. Parameters are optimized in 2012 and validated in 2013 against the in situ network. RMSD and unbiased RMSD (ubRMSD) assess resulting surface soil moisture behavior. At all sites, assigning SHP parameters from a different soil texture than the one that is mapped decreases the RMSD by an average of 0.029 cm3 cm−3. Similar improvements result from calibrating parameters using in situ network data (0.031 cm3 cm−3). Calibrations using remotely sensed data show comparable success (0.029 cm3 cm−3) if the SMOS product has no bias. Calibrated simulations are superior to texture-based simulations in their ability to decrease ubRMSD at times of year when the default simulation is worst. Changes to both RMSD and ubRMSD are small when the default simulation is already good. Most calibrated simulations have higher runoff ratios than do texture-based simulations, a change that warrants further evaluation. Overall, parameter selection using SMOS data shows good potential where biases are low. [ABSTRACT FROM AUTHOR]

This study examines the capability of a new microwave land data assimilation system (LDAS) for estimating soil moisture in semiarid regions, where soil moisture is very heterogeneous. This system assimilates the Advanced Microwave Scanning Radiometer for Earth Observing System (AMSR-E) 6.9- and 18.7-GHz brightness temperatures into a land surface model (LSM), with a radiative transfer model as an observation operator. To reduce errors caused by uncertainties of system parameters, the LDAS uses a dual-pass assimilation algorithm, with a calibration pass to estimate major model parameters from satellite data and an assimilation pass to estimate the near-surface soil moisture. Validation data of soil moisture were collected in a Mongolian semiarid region. Results show that (i) the LDAS-estimated soil moistures are comparable to areal averages of in situ measurements, though the measured soil moistures were highly variable from site to site; (ii) the LSM-simulated soil moistures show less biases when the LSM uses LDAS-calibrated parameter values instead of default parameter values, indicating that the satellite-based calibration does contribute to soil moisture estimations; and (iii) compared to the LSM, the LDAS produces more robust and reliable soil moisture when forcing data become worse. The lower sensitivity of the LDAS output to precipitation is particularly encouraging for applying this system to regions where precipitation data are prone to errors. [ABSTRACT FROM AUTHOR]

This paper presents a study undertaken in preparation of the work leading up to the assimilation of Soil Moisture and Ocean Salinity (SMOS) observations into the land surface model (LSM) Interaction Soil Biosphere Atmosphere (ISBA) at Météo-France. This study consists of an intercomparison experiment of different space-borne platforms providing surface soil moisture information [Advanced Microwave Scanning Radiometer for Earth Observing (AMSR-E) and European Remote Sensing Satellite Scatterometer (ERS-Scat)] with the reanalysis soil moisture predictions over France from the model suite of Système d'analyse fournissant des renseignements atmosphériques à la neige (SAFRAN), ISBA, and coupled model (MODCOU; SIM) of Météo-France for the years of 2003–05. Both modeled and remotely sensed data are initially validated against in situ observations obtained at the experimental soil moisture monitoring site Surface Monitoring of the Soil Reservoir Experiment (SMOSREX) in southwestern France. Two different AMSR-E soil moisture products are compared in the course of this study—the official AMSR-E product from the National Snow and Ice Data Center (NSIDC) and a new product developed at the Vrije Universiteit Amsterdam and NASA (VUA–NASA)—which were obtained using two different retrieval algorithms. This allows for an additional assessment of the different algorithms while using identical brightness temperature datasets. This study shows that a good correlation generally exists between AMSR-E (VUA–NASA), ERS-Scat, and SIM for low altitudes and low-to-moderate vegetation covers (1.5–3 kgm-2 vegetation water content), with a reduction in the correlation in mountainous regions. It also shows that the AMSR-E (NSIDC) soil moisture product has significant differences when compared to the other datasets. [ABSTRACT FROM AUTHOR]