Background Recently, there have been a number of studies on the association between XRCC1 polymorphisms and childhood acute lymphoblastic leukemia (ALL) risk. However, the results of previous reports are inconsistent. Thus, we performed a meta-analysis to clarify the effects of XRCC1 variants on childhood ALL risk. Methods A meta-analysis was performed to examine the association between XRCC1 polymorphisms (Arg399Gln, Arg194Trp, and Arg280His) and childhood ALL risk. We critically reviewed 7 studies with a total of 880 cases and 1311 controls for Arg399Gln polymorphism, 3 studies with a total of 345 cases and 554 controls for Arg280His polymorphism, and 6 studies with a total of 783 cases and 1180 controls for Arg194Trp polymorphism, respectively. Odds ratio (OR) and its 95% confidence interval (CI) were used. Results Significant association between XRCC1 Arg399Gln polymorphism and childhood ALL risk was observed in total population analyses (ORadditive model = 1.501, 95% CI 1.112–2.026, POR = 0.008; ORdominant model = 1.316, 95% CI = 1.104–1.569, POR = 0.002) and Asian subgroup analyses (ORadditive model = 2.338, 95%CI = 1.254–4.359, POR = 0.008; ORdominant model = 2.108, 95%CI = 1.498–2.967, POR = 0.000). No association was detected in Caucasians, Metizo and mixed populations. Ethnicity was considered as a significant source of heterogeneity in the meta-regression model. For the other two XRCC1 polymorphisms, no association with childhood ALL risk was found. Conclusions The meta-analysis results suggested that XRCC1 Arg399Gln polymorphism might be associated with elevated childhood ALL risk among Asian population.
Mobile Visual Location Recognition (MVLR) has attracted a lot of researchers' attention in the past few years. Existing MVLR applications commonly use Query-by-Example (QBE) based image retrieval principle to fulfill the location recognition task. However, the QBE framework is not reliable enough due to the variations in the capture conditions and viewpoint changes between the query image and the database images. To solve the above problem, we make following contributions to the design of a panorama based on-device MVLR system. Firstly, we design a heading (from digital compass) aware BOF (Bag-of-features) model to generate the descriptors of panoramic images. Our approach fully considers the characteristics of the panoramic images and can facilitate the panorama based on-device MVLR to a large degree. Secondly, to search high dimensional visual descriptors directly on mobile devices, we propose an effective bilinear compressed sensing based encoding method. While being fast and accurate enough for on-device implementation, our algorithm can also reduce the memory usage of projection matrix significantly. Thirdly, we also release a panoramas database as well as a set of test panoramic quires which can be used as a new benchmark to facilitate further research in the area. Experimental results prove the effectiveness of the proposed methods for on-device MVLR applications.
Water levels in the Great Lakes–St. Lawrence system located in northeastern North America are critically important to the Canadian and U.S. economies. Water managers are concerned that this system, which is currently managed by control structures at the outlets of Lakes Superior and Ontario, is not able to cope with the highly uncertain impacts of climate change. In particular, the frequency of extreme water levels throughout the system might be substantially increased. This study provides an exploratory conceptual analysis to determine the extent that new control structures at the outlet of Lake Huron or Erie (or both) and corresponding excavation along the St. Clair or Niagara River (or both) might mitigate the risks posed by future extreme water supply scenarios. Multilake parametric rule curves were developed to regulate systems enabled with these new control structures as a whole. Multiple stochastic water supply sequences were adopted that represented different future extreme climate scenarios. A multiscenario, multireservoir (multilake), biobjective simulation-optimization methodology was developed to optimize the rule curve parameters in such a way that the risk of experiencing extreme water levels is robustly minimized and fairly distributed across the system. The biobjective setting was designed to embed the secondary objective function so that the cost of the new control structures and excavation generates trade-offs between the costs and the associated achievable risk reductions. The recently developed Pareto Archived Dynamically Dimensioned Search (PA-DDS) multiobjective optimization algorithm was enabled with the efficiency-increasing “deterministic model preemption” strategy and utilized to solve the optimization problem. Results demonstrate that although systemwide regulation with the new control structures could substantially reduce the risk (i.e., by 86% compared to the current or base level of regulation), it could not eliminate such events entirely and would cause adverse effects on the lower St. Lawrence River. Numerical results also suggest that implementing a single new control point at the outlet of Lake Huron would not be effective despite its high cost; however, a single new control point at the outlet of Lake Erie would be very effective, with considerably less associated cost.
The aim of this study is to identify and consolidate reliable endoscopic features associated with H. pylori infection in gastric mucosa, which is one of the major causes of gastric cancer. A total of 256 Chinese patients with symptomatic stomach disturbances were enrolled. Pathological examination was conducted using a light microscope and biopsy specimens stained with hematoxylin-eosin. Endoscopic examination was performed using a high resolution video endoscope. The association between endoscopic features and pathological H. pylori diagnosis was compared, and endoscopic features significantly associated with H. pylori infection were identified. A total of 14 endoscopic features were observed. Six of the 14 endoscopic features, including mucus on the gastric mucosa, diffuse redness, spotty redness of fundic mucosa, enlarged fold, mucosal edema, and RAC (type D and type I), were highly associated with H. pylori infection and were significantly sensitive and specific predictors for H. pylori diagnosis. The type R RAC was not significantly associated with H. pylori diagnosis. Our results indicate that conventional endoscopy features can be used to diagnose H. pylori in Chinese patients and can help determine the risk factor for gastric cancer.