Mining Recent Frequent Itemsets in Sliding Windows over Data Streams

This paper considers the problem of mining recent frequent itemsets over data streams. As the data grows without limit at a rapid rate, it is hard to track the new changes of frequent itemsets over data streams. We propose an efficient one-pass algorithm in sliding windows over data streams with an error bound guarantee. This algorithm does not need to refer to obsolete transactions when they are removed from the sliding window. It exploits a compact data structure to maintain potentially frequent itemsets so that it can output recent frequent itemsets at any time. Flexible queries for continuous transactions in the sliding window can be answered with an error bound guarantee

Identification of multi-drug resistant genes in P. aeruginosa isolates from patients under mechanical ventilation and respiratory support in an intensive care unit

Purpose: To determine multi-drug resistant (MDR) and metallo β-lactamase (MBL)-resistant genes from Pseudomonas aeruginosa isolated from intensive care unit (ICU) patients under mechanical ventilation and respiratory support.Methods: P. aeruginosa was isolated from 387 purulent tracheobronchial secretions collected from ICU patients who were intubated and mechanically ventilated for at least 48 h. Antibiotic resistance was determined by minimum inhibitory concentration (MIC) assay while MDR genes, viz, blaTEM, blaOXA, blaVIM, blaCTX-M-15 were determined by polymerase chain reaction (PCR).Results: A total of 144 (37.2 %) P. aeruginosa were isolated from the purulent tracheobronchial secretions. A majority of the isolates (51.4 %) were resistant to gentamicin. Meropenem-gentamicin was the predominant (35.4 %) resistant combination. Out of the 144 isolates, 102 (70.8 %) were positive for blaTEM gene, 51 (35.4 %) for were positive for blaOXA gene, 22 (15.3 %) were positive for blaVIM gene, while 19 (13.2 %) were positive for blaCTX-M gene.Conclusion: The high prevalence of MDR P. aeruginosa indicates the need for continued monitoring of MDR P. aeruginosa especially in ICU patients who are under mechanical respiratory support.Keywords: Multi-drug resistance genes, Mechanical ventilator, Respiratory support, Pseudomonas aeruginos

Parallel Variable Distribution Algorithm for Constrained Optimization with Nonmonotone Technique

A modified parallel variable distribution (PVD) algorithm for solving large-scale constrained optimization problems is developed, which modifies quadratic subproblem QPl at each iteration instead of the QPl0 of the SQP-type PVD algorithm proposed by C. A. Sagastizábal and M. V. Solodov in 2002. The algorithm can circumvent the difficulties associated with the possible inconsistency of QPl0 subproblem of the original SQP method. Moreover, we introduce a nonmonotone technique instead of the penalty function to carry out the line search procedure with more flexibly. Under appropriate conditions, the global convergence of the method is established. In the final part, parallel numerical experiments are implemented on CUDA based on GPU (Graphics Processing unit)

Early cretaceous ridge subduction in the Shandong Peninsula, Eastern China, indicated by Laoshan A-type granite

Early Cretaceous A-type granites are widespread in the Shandong Peninsula, which can be used to elucidate the tectonic evolution of the eastern China and the destruction of the North China Craton. However, their genesis is still controversial. Several competing models, ranging from slab break-off, postorogenic extension, foundering of the lower crust and ridge subduction, were proposed. Here, we report zircon U–Pb ages, whole-rock and apatite geochemical compositions of the Laoshan granite and discuss its tectonic implications. The Laoshan granite has typical characteristics of A-type granite with high FeOT/(FeOT + MgO) ratios (0.90–0.97) and 10000*Ga/Al ratios (2.70–3.36) and high total alkali (Na2O + K2O: 7.95–8.70 wt%) contents and Zr+Nb+Ce+Y (most >350 ppm) concentrations. The Laoshan granite is further classified as A1-type based on the Yb/Ta-Y/Nb and Ce/Nb-Y/Nb diagrams and the Nb-Y-3Ga and Nb-Y-Ce triangular discriminant diagrams. Zircon U–Pb dating of two Laoshan granite samples yielded emplacement ages of 117.8 ± 1.0 Ma and 120.1 ± 1.3 Ma, respectively. The oxygen fugacity of the Laoshan granite magma is low, as indicated by zircon Ce4+/Ce3+ ratios (most <300). The crystallization temperature of zircon varies significantly, ranging from 652 to 830°C. The apatite compositions show that the Laoshan granite has high F (2.09–2.72 wt%) and low Cl (0.01–0.09 wt%) contents, consistent with influence by fluid released from the decomposition of phengite. Apatite rare earth elements show that mantle sources are also involved in Laoshan A-type granite. Combined previous studies of A-type granitic plutons in the Shandong Province and the Lower Yangtze River belt with the drifting history of the Pacific plate, we propose that the flat subduction of the spreading ridge between the Pacific and the Izanagi plates was responsible for the formation of Laoshan A-type granite

ABO genotype alters the gut microbiota by regulating GalNAc levels in pigs.

peer reviewedThe composition of the intestinal microbiome varies considerably between individuals and is correlated with health1. Understanding to what extend and how host genetics contributes to this variation is paramount yet has proven difficult as few associations have been replicated, particularly in humans2. We herein study the effect of host genotype on the composition of the intestinal microbiota in a large mosaic pig population. We show that, under conditions of exacerbated genetic diversity and environmental uniformity, microbiota composition and abundance of specific taxa are heritable. We map a quantitative trait locus affecting the abundance of Erysipelotrichaceae species and show that it is caused by a 2.3-Kb deletion in the N-acetyl-galactosaminyl-transferase gene underpinning the ABO blood group in humans. We show that this deletion is a ≥3.5 million years old trans-species polymorphism under balancing selection. We demonstrate that it decreases the concentrations of N-acetyl-galactosamine in the gut thereby reducing the abundance of Erysipelotrichaceae that can import and catabolize N-acetyl-galactosamine. Our results provide very strong evidence for an effect of host genotype on the abundance of specific bacteria in the intestine combined with insights in the molecular mechanisms that underpin this association. They pave the way towards identifying the same effect in human rural populations

Reward Versus Nonreward Sensitivity of the Medial Versus Lateral Orbitofrontal Cortex Relates to the Severity of Depressive Symptoms

BackgroundThe orbitofrontal cortex (OFC) is implicated in depression. The hypothesis investigated was whether the OFC sensitivity to reward and nonreward is related to the severity of depressive symptoms.MethodsActivations in the monetary incentive delay task were measured in the IMAGEN cohort at ages 14 years (n = 1877) and 19 years (n = 1140) with a longitudinal design. Clinically relevant subgroups were compared at ages 19 (high-severity group: n = 116; low-severity group: n = 206) and 14.ResultsThe medial OFC exhibited graded activation increases to reward, and the lateral OFC had graded activation increases to nonreward. In this general population, the medial and lateral OFC activations were associated with concurrent depressive symptoms at both ages 14 and 19 years. In a stratified high-severity depressive symptom group versus control group comparison, the lateral OFC showed greater sensitivity for the magnitudes of activations related to nonreward in the high-severity group at age 19 (p = .027), and the medial OFC showed decreased sensitivity to the reward magnitudes in the high-severity group at both ages 14 (p = .002) and 19 (p = .002). In a longitudinal design, there was greater sensitivity to nonreward of the lateral OFC at age 14 for those who exhibited high depressive symptom severity later at age 19 (p = .003).ConclusionsActivations in the lateral OFC relate to sensitivity to not winning, were associated with high depressive symptom scores, and at age 14 predicted the depressive symptoms at ages 16 and 19. Activations in the medial OFC were related to sensitivity to winning, and reduced reward sensitivity was associated with concurrent high depressive symptom scores

Estimation of Evapotranspiration and Soil Water Content at a Regional Scale Using Remote Sensing Data

The timely and accurate estimation of soil water content (SWC) and evapotranspiration (ET) is of great significance in drought estimation, irrigation management, and water resources comprehensive utilization. The unsupervised classification was used to identify the crops in the region. Based on MOD16A2 and the meteorological data, a SEBS model was used to estimate the ET in the Jiefangzha Irrigation Field from 2011 to 2015. Based on the crop water stress index (CWSI), the SWC in 2014 was retrieved and verified with the measured SWC on different underlying surfaces (sunflower, corn, wheat, and pepper). The results showed that: (1) The positional accuracy of maize, sunflower, wheat, and pepper are 0.81, 0.80, 0.90, and 0.82, respectively; (2) The annual ET from 2011 to 2015 presented well the spatial distribution of the ET within the field; (3) The validation results of the estimated SWC on the underlying surface of wheat and sunflower showed a good robustness, the R2 was 0.748 and 0.357, respectively, the RMSE was 2.61% and 2.309%, respectively, and the MAE was 2.249% and 1.975%, respectively. However, for maize and pepper with more irrigation times, the SWC estimation results, based on the CWSI were poor, indicating that the method was more sensitive to soil drought and suitable for the crop SWC estimation with less irrigation and drought tolerance. The results can provide a reference for the agricultural water resources management and the irrigation forecast at a regional scale