No abstract

Land resource management requires extensive land mapping. Conventional soil mapping takes a long time and is expensive; therefore, geographic information system data as a predictor in soil texture modeling can be used as an alternative solution to shorten time and reduce costs. Through digital elevation model data, topographic variability can be obtained as an independent variable in predicting soil texture. Geographically weighted regression is used to observe the effects of spatial heterogeneity. This study uses a data set of 50 observation points, each of which had soil particle-size fraction attributes and eight local morphological variables. The covariates used in this study are eastness aspects, northness aspects, slope, unsphericity curvature, vertical curvature, horizontal curvature, accumulation curvature, and elevation. Prediction using geographically weighted regression shows more results compared to multiple linear regression models. The spatial location can affect product Y, with the R2 value of 0.81 in the sand fraction, 0.57 in the silt fraction, and 0.33 in the clay fraction.

ABSTRACT Background. Disorders of Sex Development (DSD) is a condition where the development of sex chromosomes, gonads, and/or one’s anatomy is atypical. Its causes are often due to genetic mutations, although some are also linked to environmental risk factors. These multiple aetiologies lead to varied clinical findings, ranging from obvious ambiguous genitals to subtle ones in different regions worldwide, signalling a hint of geographical variability. Objective. This study wishes to observe the variations of clinical findings of DSD patients geographically in South Sumatera. Methods. This was an observational study using patients’ medical records in RSUP Dr. Mohammad Hoesin Palembang. Both inpatients and outpatients during five-year period span (2013-2017) with clinical findings suited DSD criteria based on Chicago Consensus in 2006 were included in this study. Results. One hundred and forty nine patients from cities and regencies in South Sumatera province and other provinces like Jambi, Lampung, Bengkulu, Bangka-Belitung, and even Riau were included in this study. Among sixteen clinical findings identified, hypospadias ranked first (59.06%), both in general, and in each regions as well. When set by side with other regions, Palembang city as the capital city of South Sumatera province displays twelve out of sixteen clinical findings documented in this study, showing a lot more variety. Conclusion. Every regions show difference clinical findings. Some regions housed clinical findings that were not found in other regions. However, hypospadias is the most commonly found clinical findings in all regions. It is suspected due to its correlation with certain environmental risks, that the occurence of it becomes rather often, compared to other DSD conditions. Future studies considering risk factors involvement in order to elucidate both differences and similarities found in each regions are strongly suggested.   Keywords: Disorders of Sex Development, DSD, Geographical variations, South Sumatera

Multiple linear regression is a method used to model or predict an object that sees the relationship between a dependent variable and a group of independent variables. Geographically Weighted Regression (GWR) is the development of multiple linear regression involving geographical factors. In this study, both methods were used in the study to analyze one of the soil elements, namely the silt soil texture. Through the Digital Elevation Model (DEM) data, the topographic variables used in the study are Eastness Aspects (Ae), Northness Aspects (An), Slope (S), Unsphericity Curvature (M), Vertical Curvature (Kv), Horizontal Curvature (Kh), Accumulation Curvature (Ka ) and Elevation (Elv). The results showed that the GWR model with fixed Gaussian weighting better than the multiple linear regression model. R 2 value of GWR was 57 %, greater than the multiple regression, which was 55%. And the SSE of GWR and multiple regression value were 2014,69 and 2177,19 respectively.