3 research outputs found
Comprehensive evaluation of Pleiades-1A bundle images for geospatial applications
WOS: 000461764800001This paper presents the results of comprehensive evaluation of Pleiades 1A which is the first civilian satellite of Europe with sub-meter resolution. The analyses consist of radiometric evaluation, georeferencing accuracy assessment, pan-sharpening performance, digital surface/terrain model quality and vector map production. The effective resolution is estimated with a factor slightly below 1.0 for triplet panchromatic images, and signal to noise ratio is in the range of other comparable space borne images. The georeferencing accuracy was estimated with a standard deviation in X and Y directions in the range of 0.45m by bias-corrected and sensor-dependent rational functional model. 3D standard deviation of +/- 0.44m in X direction, +/- 0.51m in Y direction and +/- 1.82m in the Z direction were reached in spite of the very narrow angle of convergence by the same mathematical model. The generated digital surface/terrain models were achieved with +/- 1.6m standard deviation in Z direction in relation to a reference digital terrain model. The pan-sharpened images were generated by various methods, and were validated by quantitative and qualitative analyses. Moreover, a vector map was generated in the level of detail 0 to analyse information content
A Case of Vitamin D-Dependent Rickets Type 1A with a Novel Mutation in the Uzbek Population
Vitamin D-dependent rickets type 1A (VDDR-1A) (Online Mendelian Inheritance in Man #264700) is a rare, autosomal recessively inherited disorder due to inactivating mutations in CYP27B1. It is characterized by early onset of rickets with hypocalcemia. We aimed to describe the clinical and laboratory findings in a VDDR-1A case and to report a novel homozygote truncating mutation NM_000785.3 c.403C>T (p.Q135*) in CYP27B1 which to our knowledge is the first described mutation in the Uzbek population. The patient was admitted with tetany at the age of 12 months. He was a healthy Uzbek boy until 9 months of age when he had a seizure due to hypocalcemia. Vitamin D treatment was given orally in Turkmenistan (no data available for dose and duration). The patient was the product of a consanguineous marriage. His brother had died with hypocalcemia and pneumonia. At physical examination, anthropometric measurements were within normal limits; he had caput quadratum, enlarged wrists, and carpopedal spasm. Blood calcium, phosphorus, alkaline phosphatase, and parathormone (PTH) levels were 5.9 mg/dL, 3.5 mg/dL, 987 IU/L, and 182.8 pg/mL (12-72), respectively. Radiological findings included cupping and fraying of the radial and ulnar metaphyses. Renal ultrasound revealed nephrocalcinosis (grade 1). Despite high serum PTH and 25-hydroxyvitamin D3 levels, 1,25-dihydroxyvitamin D3 level was low, suggesting a diagnosis of VDDR-1A. The patient was treated with calcium carbonate and calcitriol. DNA sequencing revealed a novel homozygous mutation of NM_000785.3 c.403C>T (p.Q135*) in CYP27B1. VDDR-1A is a rare disorder which needs to be considered even in countries where nutritional vitamin D deficiency is still common