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The automated analysis of large areas with respect to land-cover and land-use is nowadays typically performed based on the use of hyperspectral or multispectral data acquired from airborne or spaceborne platforms. While hyperspectral data offer a more detailed description of the spectral properties of the Earth's surface and thus a great potential for a variety of applications, multispectral data are less expensive and available in shorter time intervals which allows for time series analyses. Particularly with the recent availability of multispectral Sentinel-2 data, it seems desirable to have a comparative assessment of the potential of both types of data for land-cover and land-use classification. In this paper, we focus on such a comparison and therefore involve both types of data. On the one hand, we focus on the potential of hyperspectral data and the commonly applied techniques for data-driven dimensionality reduction or feature selection based on these hyperspectral data. On the other hand, we aim to reason about the potential of Sentinel-2 data and therefore transform the acquired hyperspectral data to Sentinel-2-like data. For performance evaluation, we provide classification results achieved with the different types of data for two standard benchmark datasets representing an urban area and an agricultural area, respectively. [ABSTRACT FROM AUTHOR]

Purpose:  Hepatic portal venous gas (HPVG) is a rare clinical finding, often caused by a severe underlying disease. In the literature as well as in clinical practice, HPVG is considered "signum malum" with a poor prognosis and bowel ischemia as the most common cause. Most studies are based on the results of computed tomography (CT) examinations. The aim of this retrospective study is to report on the prevalence, causes, and clinical course of HPVG in a monocentric cohort of abdominal ultrasound (US) investigations., Materials and Methods:  The US database of an academic teaching hospital was searched with specific keywords (timespan 01/2000 to 12/2020). Reports, pictures, and clinical data of all cases with HPVG were re-evaluated., Results:  Out of 134 804 US examinations, 8 HPVG cases were identified. There was a wide variety of underlying diseases, with mesenteric ischemia being seen in only 2 cases. 5 patients were discharged in stable condition, with 4 of them having undergone surgical treatment. 2 patients who had rejected further measures died, and one was lost to follow-up., Discussion:  HPVG is a rare phenomenon in clinical US. However, ultrasonographic prevalence is comparable to the prevalence in CT studies. Underlying diseases are mostly severe, and in nearly all cases an underlying cause can be found by thorough investigation. In some cases, US may even be superior to CT scans for the detection of HPVG. Despite its rarity, every sonographer should know the typical sonographic presentation of HPVG, and appropriate images should be included in US teaching modules., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Background:  Neuroendocrine tumors (NET) diagnosed during pregnancy are extremely rare. This case report describes diagnosis and treatment of a metastasized pancreas NET that became symptomatic in the second trimester., Case Description:  A 33-year-old patient presented to the emergency department in the 19 th week of pregnancy (WOP) with persistent diarrhea. Laboratory tests showed a pronounced hypercalcemia (3.53 mmol/l). Imaging revealed a mass in the pancreatic corpus/tail with extensive liver metastasis. Histologically, a NET (G2, SSTR-positive) with paraneoplastic parathormone-related-peptide secretion was found to be the cause of hypercalcemia. Under a treatment with octreotide, calcium values normalized and diarrhea stopped. After delivery of a healthy child (32.WOP via cesarean section) tumor progress was found. The pancreatic mass was resected completely, the liver metastases as far as possible. Postoperatively, in a CT scan, residual suspicious liver lesions could be found, and a palliative therapy with lanreotide was initiated. With this treatment, the patient has been asymptomatic for one year, and serum calcium remained normal. The child developed normally., Discussion:  This unusual case shows that even in extensively metastasized symptomatic NETs during pregnancy, there may be sufficient diagnostic and therapeutic options that allow for a continuation of pregnancy in close interdisciplinary cooperation under careful risk-benefit assessment for mother and child., Competing Interests: JS erhielt Vortragshonorare von Novartis und Ipsen und nahm an Advisory Boards von Novartis und ADVANZ Pharma teil. Die anderen Autoren erklären, dass kein Interessenkonflikt besteht., (Thieme. All rights reserved.)

Background and Objective: Allergic diseases of the respiratory tract are common atopic diseases in the population. Pollen of plants are one of their main causes. Pollen of trees, grasses, and weeds like mugwort are of particular importance in this context. The purpose of the present study was to determine the association between typical respiratory symptoms due to pollen allergens and the sensitization to pollen of ragweed and mugwort in adults., Methods: 1039 participants (18 to 66 years) from Southwest Germany were included in this cross-sectional study. Complains typically for aeroallergens were recorded by questionnaire. In-vitro existing sensitizations were determined for grasses/early bloomer (gx1), trees (tx6), mugwort (w6 and Art-v1) and ragweed (w1 and Amb-a1) by testing for specific IgE-antibodies., Results: In a screening test with a mixed allergen sample (sx1) 36.0 % of the participants showed an aeroallergen sensitization. Consecutive investigations of these 374 positive samples revealed a sensitization to grasses/early bloomer, trees, ragweed (w1), mugwort (w6) and the major allergens ragweed (Amb-a1) and mugwort (Art-v1) in 61.8 %, 54.5 %, 29.9 %, 24.3 %, 1.9 %, and 12.3 %, respectively. This corresponds to 22.2 %, 19.6 %, 10.8 %, 8.7 %, 0.7 % and 4.4 %, respectively, in the whole study population. The participants tested positively stated significantly more disorders. On average, 51.1 % had known hay fever, 65.2 % sneezing without cold and 41.5 % sneezing due to contact with grasses or flowers. In contrast, participants tested negatively stated disorders in only 4.4 %, 32.5 %, and 3.9 %, respectively., Conclusion: In Southwest Germany, sensitizations to plant pollen mainly are still caused by grasses, trees, and weeds like mugwort. A sensitization to pollen of ragweed alone is rare until now. However, in case of continuous allergic disorders of the respiratory tract in late summer, a sensitization to ragweed can be important for differential diagnostics., (© Georg Thieme Verlag KG Stuttgart · New York.)