754 research outputs found
Optimization of Analytic Window Functions
Analytic functions represent the state-of-the-art way of performing complex
data analysis within a single SQL statement. In particular, an important class
of analytic functions that has been frequently used in commercial systems to
support OLAP and decision support applications is the class of window
functions. A window function returns for each input tuple a value derived from
applying a function over a window of neighboring tuples. However, existing
window function evaluation approaches are based on a naive sorting scheme. In
this paper, we study the problem of optimizing the evaluation of window
functions. We propose several efficient techniques, and identify optimization
opportunities that allow us to optimize the evaluation of a set of window
functions. We have integrated our scheme into PostgreSQL. Our comprehensive
experimental study on the TPC-DS datasets as well as synthetic datasets and
queries demonstrate significant speedup over existing approaches.Comment: VLDB201
Gastropericardial Fistula as a Complication in a Refractory Gastric Ulcer after Esophagogastrostomy with Gastric Pull-Up
A gastropericardial fistula, defined as penetration of a gastric lesion into the pericardium, is a rare occurrence. Such a fistula is usually associated with a huge ulcer in the gastric fundus, an ulcer within a hiatus hernia, a history of esophagogastric surgery, the concurrent use of non-steroidal anti-inflammatory drugs (NSAIDs), or Zollinger-Ellison syndrome. The patient in this case presented with shoulder pain and melena, caused by a gastropericardial fistula that had occurred as a late complication of postoperative esophagogastrostomy and a refractory gastric ulcer. Despite the severity of the condition, the patient showed great improvement after medical treatment and the fistula was cured at the end
A school-based comprehensive lifestyle intervention among Chinese kids against Obesity (CLICK-Obesity) in Nanjing City, China: The baseline data
Background: urgent development of effective interventions to prevent rapidly rising childhood obesity in China is needed. Methods: Between May 2010 and December 2013, a cluster randomized controlled trial was conducted among 4 graders in eight urban primary schools randomly assigned to intervention or control groups in Nanjing, China. A multi-component intervention program was implemented within the treatment group, while students in the control group followed their usual health education curriculum without additional intervention. Results: At baseline, 638 and 544 students were enrolled in the intervention and control group, respectively. The prevalence of excess body weight was 26.8%, with 27.4% in the intervention group and 26.1% in the control group (p=0.61). The mean (SD) BMI and WC was 18.7 (3.0) and 63.0 (9.2) for participants in intervention schools, and 18.5 (2.9) and 63.6 (8.7) for students in control group, separately (p=0.24 and 0.41, respectively). Compared to those who were not aware of what lifestyle/behavior factors were unhealthy, students who were aware of the unhealthy lifestyle/ behavior factors consumed fewer fried snacks (0.46±0.76 serves/week vs 0.65±0.91 serves/week;
Effect of lens opacity on retinal oxygen saturation in patients with diabetic cataract
AIM: To investigate the effect of crystal turbidity on retinal oxygen saturation in patients with diabetic cataract. METHODS:This was a cross-sectional study. Totally 68 patients with 68 eyes of diabetic cataract admitted to our hospital from June 2017 to December 2017 were selected as subjects. Retinal oximetry was used to measure the blood oxygen saturation of the retinal veins, veins, and their supraorbital, nasal, subnasal, and infraorbital branches. The objective scatter index(OSI)of the eye was measured by Visual Quality Analysis System II, and the degree of opacity of the lens was graded according to OSI. RESULTS:The blood oxygen saturation of the retinal artery and its branches in this group were 101.39%±10.84%, 106.19%±11.40%, 103.22%±10.91%, 102.36%±20.31%, and 101.29%±13.88%, respectively. The oxygen saturation of the retinal vein and its branches were 62.51%±8.95%, 66.37%±10.74%, 64.81%±8.97%, 58.37%±13.85%, and 58.66%±19.94%, respectively. The difference between arteriovenous oxygen saturation was 40.72%±12.08%. In this group of patients, 68 patients with 68 eyes had an OSI value of 4.21±3.14. Among them, 15 eyes were turbid at the first stage, 14 eyes were turbid at level 2, 23 eyes were turbid at level 3, and 16 eyes were turbid at level 4. Pearson correlation analysis showed that the retinal veins, veins and their branches were negatively correlated with OSI(both PPPPP>0.05). There was no significant difference in the difference of arteriovenous oxygen saturation between the patients with different degrees of lens opacity(P>0.05).CONCLUSION: In patients with diabetic cataract, when the degree of lens opacity is 1 to 3, the degree of abnormality of retinal blood oxygen metabolism is not obvious. When the degree of lens opacity reaches 4, the blood oxygen saturation of the retinal veins, veins and their branches will decrease
Role of 18F-FDG PET Scans in Patients with Helicobacter pylori-Infected Gastric Low-Grade MALT Lymphoma
BACKGROUND/AIMS: Endoscopic ultrasound (EUS) plays a crucial role in the assessment and treatment of low-grade gastric mucosa-associated lymphoid tissue (MALT) lymphoma; however, interobserver variation, inadequate accuracy in judging the depth of tumor invasion, and histological heterogeneity of the tumor can limit its role. Thus, we have assessed the role of (18)F-FDG PET scans in the management of Helicobacter pylori-infected gastric MALT lymphoma.
METHODS: Eighteen patients with H. pylori-infected low-grade gastric MALT lymphoma underwent an (18)F-FDG PET scan prior to receiving H. pylori eradication therapy. We analyzed these patients' clinicopathologic data and measured the baseline and change in the metabolic activity of the tumor using standardized uptake values (SUVs).
RESULTS: Two patients failed to achieve complete remission of the low-grade gastric MALT lymphoma after successful H. pylori eradication. The baseline SUVs were significantly higher in these patients compared to successfully treated patients, 13.35±0.07 vs 2.98±0.93, respectively (n=2 vs n=16, p<0.001). The reduction in the SUV was significantly greater in the complete remission patients compared to treatment failure patients (p=0.018).
CONCLUSIONS: A high SUV at baseline (18)F-FDG PET and a lower reduction in the SUV within 3 months after eradication therapy are associated with treatment failure in H. pylori-positive low-grade gastric MALT lymphoma patients undergoing eradication treatment.ope
Optimizing Peri-URban Ecosystems (PURE) to re-couple urban-rural symbiosis
Globally, rapid urbanization, along with economic development, is dramatically changing the balance of biogeochemical cycles, impacting upon ecosystem services and impinging on United Nation global sustainability goals (inter alia: sustainable cities and communities; responsible consumption and production; good health and well-being; clean water and sanitation, and; to protect and conserve life on land and below water). A key feature of the urban ecosystems is that nutrient stocks, carbon (C), nitrogen (N) and phosphorus (P), are being enriched. Furthermore, urban ecosystems are highly engineered, biogeochemical cycling of nutrients within urban ecosystems is spatially segregated, and nutrients exported (e.g. in food) from rural/peri-urban areas are not being returned to support primary production in these environments. To redress these imbalances we propose the concept of the Peri-URban Ecosystem (PURE). Through the merging of conceptual approaches that relate to Critical Zone science and the dynamics of successional climax PURE serves at the symbiotic interface between rural/natural and urban ecosystems and allow re-coupling of resource flows. PURE provides a framework for tackling the most pressing of societal challenges and supporting global sustainability goals
Rebamipide May Be Comparable to H2 Receptor Antagonist in Healing Iatrogenic Gastric Ulcers Created by Endoscopic Mucosal Resection: A Prospective Randomized Pilot Study
Endoscopic mucosal resection (EMR) results in the formation of iatrogenic gastric ulcers and the optimal treatments for such ulcers are still unclear. We aimed to evaluate the efficacy of rebamipide in the management of EMR-induced ulcers by comparing it with an H2 receptor antagonist. After EMR, patients were randomly assigned into either rebamipide or famotidine groups. All patients received a one-week lansoprazole 30 mg q.d. therapy followed by three-week famotidine (20 mg b.i.d.) or rebamipide (100 mg t.i.d.) therapy. Four weeks after the treatments, ulcer sizes, stages, bleeding rates, and ulcer-related symptoms were compared using endoscopy and a questionnaire. A total of 63 patients were enrolled in this study. Finally, 51 patients were analyzed, 26 in rebamipide and 25 in famotidine group. Baseline characteristics were not significantly different between the two groups. Four weeks after EMR, the two groups were comparable in terms of ulcer reduction ratio (P=0.297), and ulcer stage (P=1.000). Moreover, no difference was observed with regard to ulcer-related symptoms, drug compliance, adverse drug event rates, and bleeding rates. Our data suggest that rebamipide is not inferior to famotidine in healing iatrogenic gastric ulcers, and could be a therapeutic option in the treatment of such ulcers
Revisiting Emission-Line Measurement Methods for Narrow-Line Active Galactic Nuclei
Measuring broad emission-line widths in active galactic nuclei (AGN) is not
straightforward owing to the complex nature of flux variability in these
systems. Line-width measurements become especially challenging when
signal-to-noise is low, profiles are narrower, or spectral resolution is low.
We conducted an extensive correlation analysis between emission-line
measurements from the optical spectra of Markarian 142 (Mrk 142; a narrow-line
Seyfert galaxy) taken with the Gemini North Telescope (Gemini) at a spectral
resolution of 185.6+\-10.2 km/s and the Lijiang Telescope (LJT) at 695.2+\-3.9
km/s to investigate the disparities in the measured broad-line widths from both
telescope data. Mrk~142 posed a challenge due to its narrow broad-line
profiles, which were severely affected by instrumental broadening in the
lower-resolution LJT spectra. We discovered that allowing the narrow-line flux
of permitted lines having broad and narrow components to vary during spectral
fitting caused a leak in the narrow-line flux to the broad component, resulting
in broader broad-line widths in the LJT spectra. Fixing the narrow-line flux
ratios constrained the flux leak and yielded the Hydrogen-beta broad-line
widths from LJT spectra 54\% closer to the Gemini Hydrogen-beta widths
than with flexible narrow-line ratios. The availability of spectra at different
resolutions presented this unique opportunity to inspect how spectral
resolution affected emission-line profiles in our data and adopt a unique
method to accurately measure broad-line widths. Reconsidering line-measurement
methods while studying diverse AGN populations is critical for the success of
future reverberation-mapping studies. Based on the technique used in this work,
we offer recommendations for measuring line widths in narrow-line AGN.Comment: 14 pages, 9 figures, accepted for publication in PAS
A network meta-analysis of 12,116 individuals from randomized controlled trials in the treatment of depression after acute coronary syndrome
Background:
Post-acute coronary syndrome (ACS) depression is a common but not well understood complication experienced by ACS patients. Research on the effectiveness of various therapies remains limited. Hence, we sought to conduct a network meta-analysis to assess the efficacy of different interventions for post-ACS depression in improving patient outcomes.
Methods and findings:
Three electronic databases were searched for randomised controlled trials describing different depression treatment modalities in post-ACS patients. Each article was screened based on inclusion criteria and relevant data were extracted. A bivariate analysis and a network meta-analysis was performed using risk ratios (RR) and standardized mean differences (SMD) for binary and continuous outcomes, respectively.
A total of 30 articles were included in our analysis. Compared to standard care, psychosocial therapy was associated with the greatest reduction in depression scores (SMD:-1.21, 95% CI: -1.81 to -0.61, p<0.001), followed by cognitive behavioural therapy (CBT) (SMD: -0.75, 95% CI: -0.99 to -0.52, p<0.001), antidepressants (SMD: -0.73, 95% CI: -1.14 to -0.31, p<0.001), and lastly, combination therapy (SMD: -0.15, 95% CI: -0.28 to -0.03, p = 0.016). No treatment modalities was found to be more effective in reducing depression scores when compared to one another. Additional analysis showed that these treatment modalities did not have significant impact on the overall mortality, cardiac mortality and recurrent myocardial infarction.
Conclusion:
This network meta-analysis found that the treatment effect of the various psychological modalities on depression severity were similar. Future trials on psychological interventions assessing clinical outcomes and improvement in adherence to ACS-specific interventions are needed
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