26 research outputs found
Adaptive main-memory indexing for high-performance point-polygon joins
Connected mobility applications rely heavily on geospatial joins that associate point data, such as locations of Uber cars, to static polygonal regions, such as city neighborhoods. These joins typically involve expensive geometric computations, which makes it hard to provide an interactive user experience. In this paper, we propose an adaptive polygon index that leverages true hit fltering to avoid expensive geometric computations in most cases. In particular, our approach closely approximates polygons by combining quadtrees with true hit filtering, and stores these approximations in a query-effcient radix tree. Based on this index, we introduce two geospatial join algorithms: an approximate one that guarantees a user-defined precision, and an exact one that adapts to the expected point distribution. In summary, our technique outperforms existing CPU-based joins by up to two orders of magnitude and is competitive with state-of-the-art GPU implementations
Long-term effects of medical management on growth and weight in individuals with urea cycle disorders
Low protein diet and sodium or glycerol phenylbutyrate, two pillars of recommended long-term therapy of individuals with urea cycle disorders (UCDs), involve the risk of iatrogenic growth failure. Limited evidence-based studies hamper our knowledge on the long-term effects of the proposed medical management in individuals with UCDs. We studied the impact of medical management on growth and weight development in 307 individuals longitudinally followed by the Urea Cycle Disorders Consortium (UCDC) and the European registry and network for Intoxication type Metabolic Diseases (E-IMD). Intrauterine growth of all investigated UCDs and postnatal linear growth of asymptomatic individuals remained unaffected. Symptomatic individuals were at risk of progressive growth retardation independent from the underlying disease and the degree of natural protein restriction. Growth impairment was determined by disease severity and associated with reduced or borderline plasma branched-chain amino acid (BCAA) concentrations. Liver transplantation appeared to have a beneficial effect on growth. Weight development remained unaffected both in asymptomatic and symptomatic individuals. Progressive growth impairment depends on disease severity and plasma BCAA concentrations, but cannot be predicted by the amount of natural protein intake alone. Future clinical trials are necessary to evaluate whether supplementation with BCAAs might improve growth in UCDs
Mast cell activation in Dowling-Degos disease
Dowling-Degos disease (DDD OMIM 179850) is a rare autosomal-dominant genodermatosis in the spectrum of reticulate pigmented anomalies that usually presents after puberty. It is characterised by reticulate hyperpigmentation and small brownish papules, located at various regions depending on the mutation. Loss-of-function mutations in the genes KRT5, POGLUT1, POFUT1 and PSENEN were identified for DDD. Patients with KRT5 mutations usually develop their lesions at intertriginous areas, whereas patients with POGLUT1 often show affected extremities. Histology reveals downward elongations of rete ridges with a reticulated or fenestrated pattern, occasional horn cysts and basal hyperpigmentation. The phenotype depends on the affected gene. This article is protected by copyright. All rights reserved
Extended surgical safety margins and ulceration are associated with an improved prognosis in pleomorphic dermal sarcomas
Background Pleomorphic dermal sarcomas (PDS) are frequent UV-induced sarcomas of the skin of intermediate grade malignant potential. Despite the fact that PDS have a noteworthy potential to recur (up to 28%) as well as to metastasize (up to 20%), there are no specific clinical guidelines with respect to follow-up these patients. Moreover, little is known about clinical, histological or molecular prognostic factors in PDS. Objective The aim of the present study was to identify risk factors to predict relapse in a large multicentre sample cohort of PDS which could aid to optimize personalized treatment recommendations regarding surgical safety margins and adjuvant radiotherapy. Methods Patients with a diagnosis of PDS were selected from nine European institutions based on the histopathologic criteria described by Fletcher. Clinicopathologic and follow-up data were collected and statistically analysed calculating univariate hazard ratios with 95% confidence intervals by use of the Cox proportional-hazards model and a significance level of P < 0.05. Patients with an incomplete excision of the tumour were excluded. Results Univariate Cox regression analysis of possible prognostic factors for progression-free survival (PFS) performed in 92 patients revealed that an excision margin of PDS [hazard ratio 4.478 (95% CI 1.536-13.055), P = 0.006]. Ulceration of the tumour was associated with a significantly better prognosis [0.396 (0.174-0.904), P = 0.028] whereas adjuvant radiotherapy did not reach statistical significance to improve prognosis in patients with PDS [0.775 (0.231-2.593), P = 0.679]. Gender, age, immunosuppression, intratumoural necrosis, tumour location, vertical thickness or horizontal diameter did not significantly influence PFS in PDS. Conclusion We identified surgical safety margins of PDS. These findings may be implemented into both the primary treatment as well as the further monitoring of patients with PDS