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Superiority of Dynamic Weights against Fixed Weights in Merging Multi-Satellite Precipitation Datasets over Pakistan
Data Availability Statement:
The data utilized in this study were acquired through purchase from the Pakistan Meteorology Department (PMD) and the Water and Power Development Authority. Information about the data is available at https://www.pmd.gov.pk/en/ (accessed on 1 January 2023) and http://www.wapda.gov.pk/ (accessed on 1 January 2023), respectively.Satellite precipitation products (SPPs) are undeniably subject to uncertainty due to retrieval algorithms and sampling issues. Many research efforts have concentrated on merging SPPs to create high-quality merged precipitation datasets (MPDs) in order to reduce these uncertainties. This study investigates the efficacy of dynamically weighted MPDs in contrast to those using static weights. The analysis focuses on comparing MPDs generated using the βdynamic clustered Bayesian averaging (DCBA)β approach with those utilizing the βregional principal component analysis (RPCA)β under fixed-weight conditions. These MPDs were merged from SPPs and reanalysis precipitation data, including TRMM (Tropical Rainfall Measurement Mission) Multi-satellite Precipitation Analysis (TMPA) 3B42V7, PERSIANN-CDR, CMORPH, and the ERA-Interim reanalysis precipitation data. The performance of these datasets was evaluated in Pakistanβs diverse climatic zonesβglacial, humid, arid, and hyper-aridβemploying data from 102 rain gauge stations. The effectiveness of the DCBA model was quantified using Theilβs U statistic, demonstrating its superiority over the RPCA model and other individual merging methods in the study area The comparative performances of DCBA and RPCA in these regions, as measured by Theilβs U, are 0.49 to 0.53, 0.38 to 0.45, 0.37 to 0.42, and 0.36 to 0.43 in glacial, humid, arid, and hyper-arid zones, respectively. The evaluation of DCBA and RPCA compared with SPPs at different elevations showed poorer performance at high altitudes (>4000 m). The comparison of MPDs with the best performance of SPP (i.e., TMPA) showed significant improvement of DCBA even at altitudes above 4000 m. The improvements are reported as 49.83% for mean absolute error (MAE), 42.31% for root-mean-square error (RMSE), 27.94% for correlation coefficient (CC), 40.15% for standard deviation (SD), and 13.21% for Theilβs U. Relatively smaller improvements are observed for RPCA at 13.04%, 1.56%, 10.91%, 1.67%, and 5.66% in the above indices, respectively. Overall, this study demonstrated the superiority of DCBA over RPCA with static weight. Therefore, it is strongly recommended to use dynamic variation of weights in the development of MPDs.National Natural Science Foundation of China (grant numbers 51839006 and 52250410336)
Enhancing Biomedical Text Summarization Using Semantic Relation Extraction
Automatic text summarization for a biomedical concept can help researchers to get the key points of a certain topic from large amount of biomedical literature efficiently. In this paper, we present a method for generating text summary for a given biomedical concept, e.g., H1N1 disease, from multiple documents based on semantic relation extraction. Our approach includes three stages: 1) We extract semantic relations in each sentence using the semantic knowledge representation tool SemRep. 2) We develop a relation-level retrieval method to select the relations most relevant to each query concept and visualize them in a graphic representation. 3) For relations in the relevant set, we extract informative sentences that can interpret them from the document collection to generate text summary using an information retrieval based method. Our major focus in this work is to investigate the contribution of semantic relation extraction to the task of biomedical text summarization. The experimental results on summarization for a set of diseases show that the introduction of semantic knowledge improves the performance and our results are better than the MEAD system, a well-known tool for text summarization
Specification and guideline for technical aspects and scanning parameter settings of neonatal lung ultrasound examination
Lung ultrasound (LUS) is now widely used in the diagnosis and monitor of neonatal lung diseases.Nevertheless, in the published literatures,the LUS images may display a significant variation in technical execution,while scanning parameters may influence diagnostic accuracy.The inter- and intra-observer reliabilities of ultrasound exam have been extensively studied in general and in LUS.As expected,the reliability declines in the hands of novices when they perform the point-of-care ultrasound (POC US).Consequently,having appropriate guidelines regarding to technical aspects of neonatal LUS exam is very important especially because diagnosis is mainly based on interpretation of artifacts produced by the pleural line and the lungs.The present work aimed to create an instrument operation specification and parameter setting guidelines for neonatal LUS.Technical aspects and scanning parameter settings that allow for standardization in obtaining LUS images include (1)select a high-end equipment with high-frequency linear array transducer (12-14 MHz).(2)Choose preset suitable for lung examination or small organs.(3)Keep the probe perpendicular to the ribs or parallel to the intercostal space.(4)Set the scanning depth at 4-5 cm.(5)Set 1-2 focal zones and adjust them close to the pleural line.(6)Use fundamental frequency with speckle reduction 2-3 or similar techniques.(7)Turn off spatial compounding imaging.(8)Adjust the time-gain compensation to get uniform image from the near-to far-field
Measurement of the Inclusive Jet Cross Section using the Kt algorithm in pp-bar Collisions at sqrt(s) = 1.96 TeV
We report on a measurement of the inclusive jet production cross section in
pp-bar collisions at sqrt{s} = 1.96 TeV using data collected with the upgraded
Collider Detector at Fermilab in Run II (CDF II) corresponding to an integrated
luminosity of 385 pb^-1. Jets are reconstructed using the kt algorithm. The
measurement is carried out for jets with rapidity 0.1 < | yjet | < 0.7 and
transverse momentum in the range 54 < ptjet < 700 GeV/c. The measured cross
section is in good agreement with next-to-leading order perturbative QCD
predictions after the necessary non-perturbative parton-to-hadron corrections
are included.Comment: Submitted to Phys. Rev. Let
The feasibility of an exercise intervention in males at risk of oesophageal adenocarcinoma: a randomized controlled trial
Objective: To investigate the feasibility and safety of a 24-week exercise intervention, compared to control, in males with Barrett's oesophagus, and to estimate the effect of the intervention, compared to control, on risk factors associated with oesophageal adenocarcinoma development. Methods: A randomized controlled trial of an exercise intervention (60 minutes moderate-intensity aerobic and resistance exercise five days/week over 24 weeks; one supervised and four unsupervised sessions) versus attention control (45 minutes stretching five days/week over 24 weeks; one supervised and four unsupervised sessions) in inactive, overweight/obese (25.0-34.9 kg/m2) males with Barrett's oesophagus, aged 18-70 years. Primary outcomes were obesity-associated hormones relevant to oesophageal adenocarcinoma risk (circulating concentrations of leptin, adiponectin, interleukin-6, tumour necrosis factor-alpha, C-reactive protein, and insulin resistance HOMA). Secondary outcomes included waist circumference, body composition, fitness, strength and gastro-oesophageal reflux symptoms. Outcomes were measured at baseline and 24-weeks. Intervention effects were analysed using generalised linear models, adjusting for baseline value. Results: Recruitment was difficult in this population with a total of 33 participants recruited (target sample size: n = 80); 97% retention at 24-weeks. Adherence to the exercise protocol was moderate. No serious adverse events were reported. A statistically significant intervention effect (exercise minus control) was observed for waist circumference (-4.5 95%CI -7.5, -1.4 cm; p < 0.01). Effects on primary outcomes were not statistically significant. Conclusion: This small, exploratory trial provides important information to inform future trial development including recruitment rates and estimates of effect sizes on outcomes related to oesophageal adenocarcinoma risk. Future trials should investigate a combined dietary and exercise intervention to achieve greater weight loss in this population and relax inclusion criteria to maximize recruitment. Trial Registration: Australian New Zealand Clinical Trials Registry (ANZCTR) ACTRN12609000401257. Β© 2015 Winzer et al
Hepatitis B virus genotypes and evolutionary profiles from blood donors from the northwest region of China
Hepatitis B virus (HBV) is prevalent in China and screening of blood donors is mandatory. Up to now, ELISA has been universally used by the China blood bank. However, this strategy has sometimes failed due to the high frequency of nucleoside acid mutations. Understanding HBV evolution and strain diversity could help devise a better screening system for blood donors. However, this kind of information in China, especially in the northwest region, is lacking. In the present study, serological markers and the HBV DNA load of 11 samples from blood donor candidates from northwest China were determined. The HBV strains were most clustered into B and C genotypes and could not be clustered into similar types from reference sequences. Subsequent testing showed liver function impairment and increasing virus load in the positive donors. This HBV evolutionary data for China will allow for better ELISA and NAT screening efficiency in the blood bank of China, especially in the northwest region
Multiple Wnt/Γ-Catenin Responsive Enhancers Align with the MYC Promoter through Long-Range Chromatin Loops
Inappropriate activation of c-Myc (MYC) gene expression by the Wnt/Γ-catenin signaling pathway is required for colorectal carcinogenesis. The elevated MYC levels in colon cancer cells are attributed in part to Γ-catenin/TCF4 transcription complexes that are assembled at proximal Wnt/Γ-catenin responsive enhancers (WREs). Recent studies suggest that additional WREs that control MYC expression reside far upstream of the MYC transcription start site. Here, I report the characterization of five novel WREs that localize to a region over 400 kb upstream from MYC. These WREs harbor nucleosomes with post-translational histone modifications that demarcate enhancer and gene promoter regions. Using quantitative chromatin conformation capture, I show that the distal WREs are aligned with the MYC promoter through large chromatin loops. The chromatin loops are not restricted to colon cancer cells, but are also found in kidney epithelial and lung fibroblast cell lines that lack de-regulated Wnt signaling and nuclear Γ-catenin/TCF4 complexes. While each chromatin loop is detected in quiescent cells, the positioning of three of the five distal enhancers with the MYC promoter is induced by serum mitogens. These findings suggest that the architecture of the MYC promoter is comprised of distal elements that are juxtaposed through large chromatin loops and that Γ-catenin/TCF4 complexes utilize this conformation to activate MYC expression in colon cancer cells
Metformin Represses Self-Renewal of the Human Breast Carcinoma Stem Cells via Inhibition of Estrogen Receptor-Mediated OCT4 Expression
Metformin, a Type II diabetic treatment drug, which inhibits transcription of gluconeogenesis genes, has recently been shown to lower the risk of some diabetes-related tumors, including breast cancer. Recently, βcancer stem cellsβ have been demonstrated to sustain the growth of tumors and are resistant to therapy. To test the hypothesis that metformin might be reducing the risk to breast cancers, the human breast carcinoma cell line, MCF-7, grown in 3-dimensional mammospheres which represent human breast cancer stem cell population, were treated with various known and suspected breast cancer chemicals with and without non-cytotoxic concentrations of metformin. Using OCT4 expression as a marker for the cancer stem cells, the number and size were measured in these cells. Results demonstrated that TCDD (100 nM) and bisphenol A (10 Β΅M) increased the number and size of the mammospheres, as did estrogen (10 nM E2). By monitoring a cancer stem cell marker, OCT4, the stimulation by these chemicals was correlated with the increased expression of OCT4. On the other hand, metformin at 1 and 10 mM concentration dramatically reduced the size and number of mammospheres. Results also demonstrated the metformin reduced the expression of OCT4 in E2 & TCDD mammospheres but not in the bisphenol A mammospheres, suggesting different mechanisms of action of the bisphenol A on human breast carcinoma cells. In addition, these results support the use of 3-dimensional human breast cancer stem cells as a means to screen for potential human breast tumor promoters and breast chemopreventive and chemotherapeutic agents
A Meta-Analysis of Array-CGH Studies Implicates Antiviral Immunity Pathways in the Development of Hepatocellular Carcinoma
BACKGROUND: The development and progression of hepatocellular carcinoma (HCC) is significantly correlated to the accumulation of genomic alterations. Array-based comparative genomic hybridization (array CGH) has been applied to a wide range of tumors including HCCs for the genome-wide high resolution screening of DNA copy number changes. However, the relevant chromosomal variations that play a central role in the development of HCC still are not fully elucidated.
METHODS: In present study, in order to further characterize the copy number alterations (CNAs) important to HCC development, we conducted a meta-analysis of four published independent array-CGH datasets including total 159 samples.
RESULTS: Eighty five significant gains (frequency β₯ 25%) were mostly mapped to five broad chromosomal regions including 1q, 6p, 8q, 17q and 20p, as well as two narrow regions 5p15.33 and 9q34.2-34.3. Eighty eight significant losses (frequency β₯ 25%) were most frequently present in 4q, 6q, 8p, 9p, 13q, 14q, 16q, and 17p. Significant correlations existed between chromosomal aberrations either located on the same chromosome or the different chromosomes. HCCs with different etiologies largely exhibited surprisingly similar profiles of chromosomal aberrations with only a few exceptions. Furthermore, the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated that the genes affected by these chromosomal aberrations were significantly enriched in 31 canonical pathways with the highest enrichment observed for antiviral immunity pathways.
CONCLUSIONS: Taken together, our findings provide novel and important clues for the implications of antiviral immunity-related gene pathways in the pathogenesis and progression of HCC
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