bluuebunny/crossref_metadata_2025 huggingface dataset:
Removing Scale Damage with Fast-Acting Anhydrite CaSO4 Removal System
Authors: Reyes-Garcia Enrique , Holan Kristina
Published: February 2020

The development of a highly efficient calcium sulfate (CaSO4) scale removal fluid containing a first-of-its class dissolver system is presented. Common CaSO4 scale dissolvers require chelant(s) along with scale converters. A drawback of this type of dissolver is that removal of anhydrite represents a problem if extended shut-in periods are necessary. To help minimize the nonproductive time (NPT) necessary to dissolve CaSO4, a solution has been identified that can restore production within two hours or less and is field-proven.

Mineral anhydrite and gypsum samples were exposed to dissolver formulations at 200°F under static conditions, from one hour up to 24 hours. Dissolution kinetics investigation indicates that the limiting step is a substitution surface process that catalyzes the reaction. The formulation was generated based on the discrete chemical activities of individual components with respect to anhydrite, and then refined against a performance-based design of experiments (DoE). Various chemical agents were tested for activity as a function of the chemical functionality (i.e., carboxylate, halide, etc.). Combining the results from multiple design spaces allowed determination of the most desirable formulation.

A customized performance methodology was implemented to rapidly identify formulations having a dissolution efficiency exceeding 70% within one hour, followed by a targeted design space aiming for 90% dissolution of actual wellbore anhydrite scale. All tests were conducted with low surface area samples cut from mined substrates for the purpose of experimental designs while wellbore scale was used to validate the formulation efficacy. Elemental analysis of gypsum and anhydrite dissolution products over time was conducted to elucidate kinetic parameters at 150 and 200°F from 1 to 24 hours. The dissolution of anhydrite as a function of time, at 150 and 200°F, showed limiting effect dependency as a function of scale converter concentration. Mass of scale to volume of dissolver fluid effects indicate a dependence on the converter concentration while temperature had the most significant effect. Formulations showed 60-80% dissolution in one hour using anhydrite. This signifies that wellbore and equipment clean out can be accomplished with a simple, non-corrosive treatment fluid when the mineral is of the CaSO4 type. Field trials have been conducted, demonstrating the efficacy of the fluid.

The anhydrite dissolver formulation provides mineral dissolution within one hour under conditions representative of a wellbore, such as static fluid column and temperatures of 200°F. The treatment is delivered as a one-fluid system, or single treatment design, whereas a majority of existing treatments require multiple fluids providing protection to downhole equipment such as electro submersible pumps (ESP). The new system functions without the need for prolonged well shut-ins or the use of complicated treatment fluid designs.
The Impact of Contractional Flow on the Extensional Viscosity of Polyacrylamide Polymers in Fracturing Applications
Authors: Fischer Christine , Constien Vernon , Cage Brad
Published: February 2020

High molecular weight polyacrylamide polymers have been used for many years in water floods for enhanced oil recovery (EOR) and as friction reducers in hydraulic fracturing. More recently, so called "high viscosity" versions of these polymers are being used in fracturing operations for friction reduction and also for fracture creation and proppant transport (Hu, 2018). These polymers have more complex viscous properties than materials such as guar gum or cellulose. In addition to the typical shear thinning behavior (shear viscosity), they also may have extensional viscosity thickening in convergent geometries. Separating and quantifying these properties for polyacrylamide polymers is difficult but is needed to predict their behavior not only for flow in porous media but for slot flow in hydraulic fracturing applications.

Extensional viscosity in polyacrylamide polymers may be generated in a flow field that experiences a sudden change in geometry such as a contraction. The elongational flow triggers a transition in the conformation of the molecule from a coiled to a stretched state. This conformation change can result in a sudden change in resistance to flow of several magnitudes. Screen-factor measurement used in determining the resistance factor for polymers in EOR applications have been shown to have components of both shear thinning viscosity and extensional viscosity (Lim, 1986).

A technique has been developed using contraction flow which can separate shear viscosity from apparent extensional viscosity. The contraction flow technique is useful in determining the effect on the extensional viscosity as a result of changes in molecular weight, copolymer composition, salt effects and shear degradation of polyacrylamide polymers. Examples are given which illustrate how the results are quite useful in the selection of appropriate polymers for fracturing or water flood operations.

While the extensional properties are known and the effects of the change in extensional viscosity have been better defined for flow in porous media, the definition and change in these properties have not previously been well defined for fracturing applications. Particularly, the duration of the extensional viscosity change and the effect of extensional viscosity on proppant transport and fracture geometry have not been determined.
New High Viscosity Friction Reducers for Proppant Transport in Hydraulic Fracturing
Authors: Song Jingshe , Navarrete Reinaldo , Asadi Mahmoud , Jin Bryan
Published: February 2020

The use of high viscosity friction reducers (HVFRs) has increased rapidly as replacements for linear and even crosslinked guar-based fluids for proppant transport in hydraulic fracturing. HVFRs at high loadings have significantly higher fluid viscosities than conventional friction reducers (FRs). However, the efficiency of current HVFRs is still limited. The primary objective of this study is to compare proppant transport performance of newly developed HVFRs with commercial HVFRs and guar-based systems.

Several test protocols were performed for investigating the proppant transport efficiency of HVFR systems. Five HVFRs with different structures were prepared using the inverse emulsion polymerization technique. The viscosity of these five HVFRs and a commercial HVFR were measured and compared across a wide range of concentrations under various shear rates using a rheometer with a concentric cylinder geometry. Proppant transport performance was assessed using static proppant settling tests. A conventional linear guar-based gel was also tested and compared as a reference.

Several HVFRs were tested in the laboratory. The results show that using only high shear viscosity as an indicator of proppant transport performance is not appropriate. Low shear rate viscosity is a better indicator of proppant transport. Static settling tests are a good testing method to compare the proppant transport performance of different HVFRs. The structure of HVFRs was found to be critical to the viscosity and proppant transport performance. The chemical structures of HVFRs were optimized in the laboratory. The testing results show that the newly developed HVFRs have higher viscosity and better proppant transport performance than the commercial HVFR and linear guar-based gel systems tested.

This paper provides a comprehensive study of HVFRs as replacements for linear and crosslinked guar-based systems. This study shows the effects of polymer structural features, such as charge, size and water salinity on proppant transport performance.
A Novel Relative Permeability Modifier Polymer
Authors: Yang Chao , Navarrete Reinaldo , Asadi Mahmoud
Published: February 2020

A novel branched synthetic polymer capable of changing the relative permeability of water and oil in a formation was developed. The new polymer has the capacity to anchor to the sandstone formation, allowing it to endure production fluid flow.

Thermal aging tests were conducted to evaluate the thermal stability. Gravity column tests were established as a screening method to evaluate the polymer's capacity to impair water flow and to anchor to the formation. Laboratory core flow tests were conducted using sandstone cores plugs with an air permeability of 0.8 to 5 Darcies at 200°F. The polymer was evaluated as a near wellbore treatment and as a far field treatment by altering the injection direction of the polymer slug.

Results indicate that the polymer can reduce the permeability to water without significantly impairing the permeability to oil. The regain relative water permeability was less than 20% after the injection of a relative permeability modifier (RPM) polymer. The subsequent regain relative oil permeability was above 75% and the regain relative water permeability was less than 30% after the oil injection. Results also showed that the RPM polymer had similar performance regardless of the injection direction used. Moreover, pre-flushing the core with mutual solvent and surfactants before the polymer treatment did not have a significant effect on the performance of the polymer.

The capacity to selectively modify the water permeability makes it feasible to use this polymer in a near wellbore or in a far field treatment to reduce excessive water production. Moreover, the polymer can be applied without the use of a mutual solvent and surfactants, thereby reducing treatment costs.
Non-Monotonic Retention Profiles of Suspended Particles Under Water Injection
Authors: Khazali Nastaran , Malgaresi Gabriel , Bedrikovetsky Pavel
Published: February 2020

Injection of water with particles distributed by various features (size, shape, density, surface charge, Z-potential) can highly affect the retention profile (RP) of suspended particles. The main objective of this study is to investigate non-monotonic retention profiles (NRPs) during the axi-symmetric flow of size-distributed colloids and accordingly, predict injectivity decline reliably. For this target to be achieved, coreflooding is performed by water with particles that are distributed by sizes. The results obtained by implementing derived exact upscaled equations of colloidal transport for multi-component particle population closely match by the experimental data monitored during the flood provided that the model coefficients are determined from the tuning. Altogether, four tests are conducted from which breakthrough curves (BTCs) and retention profiles in three moments can be observed. The observed close match proves the accurate representation of the mathematical model in all tests due to the higher number of degrees of freedom of the experimental data array compared to the number of tuned model parameters.
Application of Standardised Effect Sizes to Hospital Discharge Outcomes for People with Diabetes
Authors: Robbins Tim David , Keung Sarah N. Lim Choi , Sankar Sailesh , Randeva Harpal , Arvanitis Theodoros N.
Published: February 2020

Background: Patients with diabetes are at an increased risk of readmission and mortality when discharged from hospital. Existing research identifies statistically significant risk factors that are thought to underpin these outcomes. Increasingly, these risk factors are being used to create risk prediction models, and target risk modifying interventions. These risk factors are typically reported in the literature accompanied by unstandardized effect sizes, which makes comparisons difficult. We demonstrate an assessment of variation between standardised effect sizes for such risk factors across care outcomes and patient cohorts. Such an approach will support development of more rigorous risk stratification tools and better targeting of intervention measures.
Methods: Data was extracted from the electronic health record of a major tertiary referral centre, over a 3-year period, for all patients discharged from hospital with a concurrent diagnosis of diabetes mellitus. Risk factors selected for extraction were pre-specified according to a systematic review of the research literature. Standardised effect sizes were calculated for all statistically significant risk factors, and compared across patient cohorts and both readmission & mortality outcome measures.
Results: Data was extracted for 46,357 distinct admissions patients, creating a large dataset of approximately 10,281,400 data points. The calculation of standardized effect size measures allowed direct comparison. Effect sizes were noted to be larger for mortality compared to readmission, as well as for being larger for surgical and type 1 diabetes cohorts of patients.
Conclusions: The calculation of standardised effect sizes is an important step in evaluating risk factors for healthcare events. This will improve our understanding of risk and support the development of more effective risk stratification tools to support patients to make better informed decisions at discharge from hospital.
neoANT-HILL: an integrated tool for identification of potential neoantigens
Authors: Coelho Ana Carolina , Fonseca Andre , Martins Danilo , Lins Paulo , Cunha Lucas da , de Souza Sandro
Published: February 2020

Background: Cancer neoantigens have attracted great interest in immunotherapy due to their capacity to elicit antitumoral responses. These molecules arise from somatic mutations in cancer cells, resulting in alterations on the original protein. Neoantigens identification remains a challenging task due largely to a high rate of false-positives. Results: We have developed an efficient and automated pipeline for the identification of potential neoantigens. neoANT-HILL integrates several immunogenomic analyses to improve neoantigen detection from Next Generation Sequence (NGS) data. The pipeline has been compiled in a pre-built Docker image such that minimal computational background is required for download and setup. NeoANT-HILL was applied in The Cancer Genome Atlas (TCGA) melanoma dataset and found several putative neoantigens including ones derived from the recurrent RAC1:P29S and SERPINB3:E250K mutations. neoANT-HILL was also used to identify potential neoantigens in RNA-Seq data with a high sensitivity and specificity.Conclusion: neoANT-HILL is a user-friendly tool with a graphical interface that performs neoantigens prediction efficiently. neoANT-HILL is able to process multiple samples, provides several binding predictors, enables quantification of tumor-infiltrating immune cells and considers RNA-Seq data for identifying potential neoantigens. The software is available through github at https://github.com/neoanthill/neoANT-HILL.
DNA methylation regulates glioma cell cycle through down-regulating MiR-133a expression
Authors: Liu Liang , Zhu Zhengquan , Li Xu , Zheng Yong
Published: February 2020

Background: MiRNAs plays a key role in regulating gene expression networks of various biological processes in many cancers.
Results: Here, we analyzed miRNA expression profiles by miRNA microarray and verified by RT-PCR. It was shown that the expression difference of miR-133a was most significantly and consistently downregulated. The proliferative capacity and cell cycle profile of cells transfected with miR-133a mimic were assessed by colony forming assay and PI staining, respectively. The target gene of miR-133a was predicted using TargetScan and verified by dual luciferase gene reporter assay. Western blotting and RT-PCR were used to analyze the expression levels of relevant factors. Methylation-specific quantitative PCR (MSP) was used to detect miR-133a methylation levels. Epigenetic regulation of miR-133a was assessed by treating the cells with the DNA methyltransferase inhibitor AZA or the histone deacetylase inhibitor TSA. We found that overexpression of miR-133a inhibited cell proliferation, induced a cell cycle arrest and downregulated the expression of Cyclin D1, Cyclin D2, and cycling-dependent killdeer 4 (CdK4). Peroxisome proliferator-activated receptor γ (PPARγ) was verified as a target gene of miR-133a. PPARγ protein levels were significantly higher in the glioma tissues, and overexpression of miR-133a markedly reduced its levels. Furthermore, forced expression of PPARγ partly abrogated the anti-proliferative effects of miR-133a. miR-133a was hypermethylated in glioma cells, and AZA treatment significantly up-regulated its levels.
Conclusions: MiR-133a is downregulated in glioma cells through promoter hypermethylation, and its forced expression inhibits glioma cell proliferation and induces G1 phase arrest by targeting PPARγ.
A simple monochromatic flow cytometric assay for assessment of intraerythrocytic development of Plasmodium falciparum
Authors: Kulkeaw Kasem , Ketprasit Nutpakal , Tungtrongchitr Anchalee , Palasuwan Duangdao
Published: February 2020

Background Gold standard microscopic examination of Plasmodium falciparum intraerythrocytic stage remains an important process for staging and enumerating parasitized erythrocytes in culture; however, microscopy is laborious and its accuracy is dependent upon the skill of the examiner. Methods In this study, ViSafe Green (VSG), which is a nucleic acid-binding fluorescent dye, was used for assessing in vitro development of P. falciparum using flow cytometry. Results Fluorescence intensity of VSG was found to depend on the developmental stage of parasites. Specifically, multiple-nuclei-containing schizonts were observed in the VSGhigh population, and growing trophozoites and ring-shaped forms were observed in the VSGintermediate and VSGlow populations. The efficacy of VSG-based assay was found to be comparable to the microscopic examination method, and it demonstrated an ability to detect as low as 0.001% of the parasitaemia estimated by Giemsa staining. Moreover, when applying VSG for anti-malarial drug test, it was able to observe the growth inhibitory effect of dihydroartemisinin, the front-line drug for malaria therapy. Conclusions Taken together, the results of this study suggest the VSG-based flow cytometric assay to be a simple and reliable assay for assessing P. falciparum malaria development in vitro.
Combining abbreviated literature searches with single-reviewer screening: three case studies of rapid reviews
Authors: Affengruber Lisa , Wagner Gernot , Waffenschmidt Siw , Lhachimi Stefan K. , Nussbaumer-Streit Barbara , Thaler Kylie , Griebler Ursula , Klerings Irma , Gartlehner Gerald
Published: February 2020

Background Decision-makers increasingly request rapid answers to clinical or public health questions. To save time, personnel, and financial resources, rapid reviews streamline the methodological steps of the systematic review process. Methods Using three cases studies, we evaluated a rapid review approach that consisted of a substantially abbreviated literature search and single-reviewer screening of abstracts and full texts. We used a convenience sample of three ongoing Cochrane reviews as reference standards. Two reviews addressed oncological topics and one addressed a public health topic. For each of the three topics, three reviewers screened the literature independently. Our primary outcome was the change in conclusions between the rapid reviews and the respective Cochrane reviews. In case the rapid approach missed studies, we recalculated the meta-analyses for the main outcomes and asked Cochrane review authors if the new body of evidence would change their original conclusion compared with the reference standards. Additionally, we assessed the sensitivity of the rapid review approach compared with the results of the original Cochrane reviews. Results For the two oncological topics (case studies 1 and 2), the three rapid reviews each yielded the same conclusions as the Cochrane reviews. However, the authors would have had less certainty about their conclusion in case study 2. For case study 3, the public health topic, only one of the three rapid reviews led to the same conclusion as the Cochrane review. The other two rapid reviews provided insufficient information for the authors to draw conclusions. Using the rapid review approach, the sensitivity was 100% (3 of 3) for case study 1. For case study 2, the three rapid reviews identified 40% (4 of 10), 50% (5 of 10), and 60% (6 of 10) of the included studies, respectively; for case study 3, the respective numbers were 38% (8 of 21), 43% (9 of 21), and 48% (10 of 21). ConclusionsWithin the limitations of these case studies, a rapid review approach that combines abbreviated literature searches with single-reviewer screening may be feasible for focused clinical questions. For complex public health topics, sensitivity seems to be insufficient.
Lack of genetic differentiation between two sympatric species of Astyanax (Characidae:Teleostei) in Lake Catemaco, Mexico
Authors: Doadrio Ignacio , Ornelas Patricia , Gonzalez Elena G. , Tautz Diethard
Published: February 2020

Background Fish of the genus Astyanax are known to be able to adapt to a wide range of ecological conditions and are especially known for repeated colorizations of cave systems. In lakes they often occur in species pairs. In the case we study here, they show major morphological differences, such that they were originally classified in different genera. Previous studies have shown that these morphological differences correlate with occupation of different trophic niches. Hence, this could be an example of ecological speciation under sympatric conditions, which predicts that differential ecological adaptation becomes coupled to assortative mating and to the formation of genetically distinct groups that may be called species. We have tested this prediction by typing a set of microsatellites for the two morphs in the lake in comparison to an allopatric population.Results While we find the expected differentiation with respect to the allopatric population, there is a complete lack of genetic differentiation between the two morphs within the lake. Hence, the two morphs in the lake are either in an extremely early phase of speciation or represent two extreme morphotypes derived from a single gene pool.Conclusions Even when we failed to recover the two morphs as reproductively isolated, this model provides a unique opportunity to characterize those factors that would promote the ecological divergence, thus, our lacustrine morphs system gives a unique opportunity to understand the genetic basis of how morphological divergence in the presence of gene flow.
Colombian frogs: promising source of new antibiotics
Authors: Alzate Esteban , Mejía Laura , Nuñez Maria Clara , Benavides Julie , Galvis-Pareja David , Zapata Paola
Published: February 2020

Background: In middle Magdalena of the Antioquia region, Colombia frog secretions have been used as antibacterial agents, the purpose of this study is to assess the antibacterial activity of six frog species secretions. Methods: the Kirby-Bauer and the microdilution methods were used to evaluate antibacterial activity of the frogs secretions against S. aureus and E. coli, using two positive controls, ampicillin and ciprofloxacin. Results: secretions of all six families showed inhibition zones, the concentration at which this zone was bigger was assayed later by the microdilution method and compared to ampicillin and ciprofloxacin. Only the secretion from the Phyllomedusidae exhibited a comparable effect to that one of control antibiotics. Conclusions: in here we provide evidence that secretions from local frogs have an antibacterial effect against two strains of bacteria, further studies are needed to identify the peptides in the secretions and a wider range of safe concentrations for human use.
Noninvasive KRAS mutation estimation in colorectal cancer using a deep learning method based on routine CT imaging
Authors: He kan , Liu Xiaoming , Li Mingyang , Li Xueyan , Yang Hualin , zhang huimao
Published: February 2020

Background: The detection of KRAS gene mutations in colorectal cancer (CRC) is key to the optimal design of individualized therapeutic strategies. The noninvasive prediction of the KRAS status in CRC is challenging. Deep learning (DL) in medical imaging has shown its high performance in diagnosis, classification, and prediction in recent years. In this paper, we investigated predictive performance by using a DL method with a residual neural network ( ResNet ) to estimate the KRAS mutation status in CRC patients based on routine pre-treatment contrast-enhanced CT imaging. Methods: We have collected a dataset consisting of 157 patients with pathology-confirmed CRC who were randomly divided into a training cohort (n = 117) and a validation cohort (n = 40). We developed an ResNet model that used portal venous phase CT images to estimate KRAS mutations in the axial, coronal, and sagittal directions of the training cohort and validated the model in the validation cohort. Several groups of expended ROI patches were generated for the ResNet model, to explore whether tissues around the tumor can contribute to cancer assessment. We also explored a radiomics model with the random forest classifier (RFC) to predict KRAS mutations and compared it with the DL model. Results: The ResNet model in the axial direction achieved the higher area under the curve (AUC) value (0.90) in the validation cohort and peaked at 0.93 with an input of “ROI and 20-pixel” surrounding area. In the training cohort, the AUC was 0.945 (sensitivity: 0.75; specificity: 0.94), and in the validation cohort, the AUC was0.818 (sensitivity: 0.70; specificity: 0.85). In comparison, the ResNet model showed better predictive ability . Conclusions: Our experiments reveal that the computerized assessment of the pre-treatment CT images of CRC patients using a DL model has the potential to precisely predict KRAS mutations. This new model has the potential to assist in noninvasive KRAS mutation estimation. Keywords: Colorectal Neoplasm, Mutation, Deep Learning
Cost-effectiveness and budget impact of flucytosine as induction therapy in the treatment of cryptococcal meningitis in HIV-infected adults in South Africa
Authors: Miot Jacqui , Leong Trudy , Takuva Simbarashe , Parrish Andrew , Dawood Halima
Published: February 2020

Background Cryptococcal meningitis in HIV-infected patients in sub-Saharan Africa accounts for three-quarters of the global cases and 135 000 deaths per annum. Current treatment includes the use of fluconazole and amphotericin B. Recent evidence has shown that the synergistic use of flucytosine improves efficacy and reduces toxicity, however affordability and availability has hampered access to flucytosine in many countries. This study investigated the evidence and cost implications of introducing flucytosine as induction therapy for cryptococcal meningitis in HIV-infected adults in South Africa. Methods A decision analytic cost-effectiveness and budget impact model was developed based on survival estimates from the ACTA trial and local costs for flucytosine as induction therapy in HIV-infected adults with cryptococcal meningitis in a public sector setting in South Africa. The model considered four treatment arms: (a) standard of care; 2-week course of amphotericin B/fluconazole (2wk AmBd/Flu), (b) 2-week course of amphotericin B/flucytosine (2wk AmBd/5FC), (c) short course; 1-week course amphotericin B/flucytosine (1wk AmBd/5FC) and (d) oral course; 2-week oral fluconazole/flucytosine (oral). A sensitivity analysis was conducted on key variables. Results The highest total treatment costs were in the 2-week AmBd/5FC arm followed by the 2-week oral regimen, then the 1-week AmBd/5FC with the lowest cost in the standard of care arm. Compared to standard of care the 1-week flucytosine course is most cost-effective at USD31/QALY, followed by the oral 2-week course at USD155/QALY and the 2-week flucytosine course at USD568/QALY. The budget impact analysis shows that the 1-week course has the lowest incremental cost, followed by the oral course and then the 2-week flucytosine course compared to what is currently spent on standard of care. Sensitivity analyses suggest that the model is most sensitive to the price of flucytosine and hospital costs, particularly length of stay. Conclusions The addition of flucytosine as induction therapy for the treatment of cryptococcal meningitis in patients infected with HIV is cost-effective regardless of whether it is used as a 1-week, 2-week or oral regimen. Savings could be achieved with early discharge of patients as well as a reduction in the price of flucytosine.
The Establishment of National Standards for Health Checks in China and a comparison with American EHE Standards
Authors: Zhu YANhui , Lei Jianbo
Published: February 2020

Objective Different institutes utilize different test standards for routine health checks in China. It is necessary and urgent to establish unified standards for health checks to conserve medical resources and reduce the social burden in China. The purpose of this study is to determine standards of health items and evaluate the advantage and disadvantage by comparing with the American executive health exam (EHE) standards. Methods We collected health check items used in 60 top hospitals within mainland China. We excluded items that occurred in less than 80%. We compared the selected items with those used in the American EHE standards. Results China’s health check included physical examination, non-infectious disease screening, malignancy screening, laboratory screening, and imaging examinations. China’s health checks included more items than those used in the American EHE standards. Conclusion Our findings showed that China’s health check protocols could be simplified, except for the items currently used in the basic physical examination and malignancy screening.
The status of serum vitamin A/E and its effect on Recurrent Respiratory Tract Infections in children aged 2 to 17 years in Beijing, China, based on cross-sectional study
Authors: Wang Xiaoyan , Jin Chunhua , Wang Jiaxin , Wang Jianhong , Zhang Lili , Li Na , Song Wenhong , Li Xingming
Published: February 2020

Objective To test the association between serum vitamin A and vitamin E and the prevalence of recurrent respiratory tract infections (RRTIs) of children and adolescents. Method A total amount of 5780 children and adolescents aged 2 to 17 were involved, who were classified into:A) Control group ;B) Diagnosed as RRTI with RTI symptoms; C) With RRTI but currently no RTI symptoms being noticed, and D) Not RRTI but showing respiratory disease symptoms. The correlation between serum vitamin A/E level and the presence of RRTIs were analyzed. Results Comparing with the prevalence of RRTI in children with normal vitamin A level, the Odds Ratio(OR) of vitamin A deficiency for RRTIs with symptoms was 8.32 (95%CI: 6.15 ～ 11.27), while the OR of marginal vitamin A deficiency was 1.30 (95%CI: 1.10 ～ 1.55). The OR of vitamin A deficiency or marginal vitamin A deficiency for asymptomatic RRTIs were 1.52 (95%CI: 1.00 ～ 2.32) and 1.30 (95%CI: 1.10 ～ 1.55) respectively, while the OR of vitamin A deficiency or marginal vitamin A deficiency for other respiratory diseases were 7.09 (95%CI: 5.37 ～ 9.37) and 1.60 (95%CI: 1.38 ～ 1.86). Whereas, the OR of vitamin E deficiency or marginal vitamin E deficiency for RRTIs or normal respiratory infections were showed without statistical significance. Conclusion The low level of vitamin A in serum is a risk factor for children and adolescents getting RRTIs or RTIs, indicating a possibly regulatory role of vitamin A in the respiratory diseases. In comparison, the vitamin E deficiency seems to have a weaker but still positive effect on the RRTIs or RTI
Randomized trial: corticoids versus placebo in severe bronchiolitis. COTHEB study.
Authors: Felipe Aida , Balaguer Mònica , Alejandre Carme , Esteban Elisabeth , Alsina Laia , Muñoz-Almagro Carmen , Esteban Maria Esther , Cambra Francisco José , Jordan Lolanda
Published: February 2020

Background: Corticosteroids as modulation the inflammatory response is a controversial issue in the treatment of bronchiolitis. This study aimed to assess whether corticoid therapy influenced the inflammatory and clinical response of critically ill infants.
Methods: Prospective, randomized, double blind placebo-controlled trial of glucocorticoids (GCT) in infants of less than 12 months with severe or moderate bronchiolitis. Patients were randomized to receive corticoid therapy or placebo. The main outcomes were: a) levels of lymphocyte; b) levels of IL-2, IL-12, and IFNγ as pro-inflammatory factors, and c) levels of IL-4 and IL-10 as anti-inflammatory response. Secondary outcomes related with the clinical response were also analyzed.
Results: 97 patients were randomized. Evolution of lymphocyte subsets was similar in both groups. Pro-inflammatory interleukins and interferon decreased, but without differences. Antiinflammatory interleukins showed a significant decrease from baseline to the end of the study, and IL-10 values were significantly lower in the GCT group. GCT group showed a lower time of mechanical ventilation and of hospitalization, but without statistically significant differences No cases of severe adverse reaction to steroids were detected.
Conclusions: administration of systemic GCT did not modify the inflammatory not the clinical response of patients with severe bronchiolitis, except for IL-10 levels that were significantly lower in the GCT group.
Trial registration: Glucocorticoid Therapy Impact on the Inflammatory Response and Clinical Evolution in Patients With Severe Bronchiolitis, NCT02571517. ClinicalTrials.gov registration number: 2011-000337-36. Date of registration: 30 june 2012 (retrospectively registered).
Difference of microbiome and antibiotic resistome between earthworm gut and soil deciphered by a continental-scale survey
Authors: Zhu Yong-Guan , Zhu Dong , Delgado-Baquerizo Manuel , Su Jian-Qiang , Ding Jing , Li Hu , Gillings Michael R. , Penuelas Josep
Published: February 2020

Background Earthworms are globally distributed and quite capable of redistributing compounds, as well as bacteria and antibiotic resistance genes (ARGs) throughout the soil profile. The spread of medically relevant ARGs in soils has become an emerging environmental and health issue globally. However, our understanding on earthworm gut microbiome and antibiotic resistome is still lacking, especially at the large scale, and little is known about the role of earthworm in the dispersal of ARGs. Methods We conducted a continental-scale survey, including samples (earthworm gut and soil) from 28 provinces across China, from both natural and agricultural ecosystems (arable land: 35 sites and forested land: 16 sites). The 16S rRNA amplicon sequencing and high throughput quantitative PCR were used to characterize the microbiome and antibiotic resistome, respectively. We further explored potential mechanisms behind changes in the abundance and diversity of ARGs in the earthworm gut. Then, the microcosm experiments and long-term field experiments with or without earthworms were employed to test the potential for earthworms to reduce the abundance of ARGs in soils. Results The diversity and structure of bacterial community were observably different between the earthworm gut and soil. Firmicutes (35.7%) and Proteobacteria (34.8%) were the dominant phyla in all earthworm gut samples. A significant correlation between bacterial community dissimilarity and spatial distance was identified in the earthworm gut. The earthworm gut consistently had a lower diversity and abundance of ARGs than in the surrounding soil. We further revealed that the change of ARGs in the earthworm gut was likely a consequence of the reduction in the abundance of mobile genetic elements and dominant bacterial phylotypes that are the likely hosts of ARGs. The microcosm study and long-term field experiments provided the experimental evidence that the presence of earthworms reduced the abundance and diversity of ARGs in soils. Conclusions Our findings highlight that earthworm gut and soil present the distinct microbiome and resistome at the continental scale, and earthworms may play an important role in the continental-scale mitigation of antibiotic resistance.
Body Mass Index- and Waist Circumference-Defined Obesity with the risk of Total Knee Arthroplasty for Osteoarthritis: A prospective cohort study
Authors: Lim Yuan Z , Wang Yuanyuan , Cicuttini Flavia M , Giles Graham G , Graves Stephen , Wluka Anita E , Hussain Sultana Monira
Published: February 2020

Background There is a discordance in classification of obesity when defined by body mass index (BMI) or waist circumference (WC). We aimed to examine whether categories of BMI- and WC-defined obesity are differentially associated with the risk of total knee arthroplasty for osteoarthritis. Methods 38,924 participants from the Melbourne Collaborative Cohort Study with BMI and WC measured at baseline (1990-1994) were included. Obesity status was defined as: not obese (non-obese BMI and non-obese WC); WC-defined obesity only (non-obese BMI and obese WC); BMI-defined obesity only (non-obese WC and obese BMI); and BMI- and WC-defined obesity. The incidence of total knee arthroplasty for osteoarthritis between January 2001 and December 2013 was determined by linking participant records to the National Joint Replacement Registry. Results Over 11.5±3.1 years follow-up, 1,875 participants underwent total knee arthroplasty for osteoarthritis. Participants with WC-defined obesity only (HR=1.79, 95%CI 1.51-2.53), BMI-defined obesity only (HR=2.39, 95%CI 2.02-2.84), and BMI- and WC-defined obesity (HR=3.14, 95%CI 2.82-3.49) had an increased risk of total knee arthroplasty compared with those who were not obese. Conclusions Individuals with either BMI- or WC-defined obesity should be targeted for prevention of knee osteoarthritis as both are significant predictors for severe osteoarthritis requiring a total knee arthroplasty.
Prevalence, antimicrobial susceptibility patterns, and associated risk factors of Salmonella and Shigella among food handlers in Adigrat University student’s cafeteria, Northern Ethiopia, 2018
Authors: Legese Haftom , Kahsay Tsega , Gebrewahd Aderajew , Berhe Birhane , Fiseha Berhane , Tadesse Senait , Gebremariam Guesh , Negash Hadush , Mardu Titsum , Tesfay Kebede , Adhanom Gebre
Published: February 2020

Background : Food handlers play a significant role in the transmission of foodborne infection. Salmonella and Shigella are the most common foodborne pathogens and their infections are a major public health problem of the globe. Thus, this study was aimed to determine the prevalence, antimicrobial susceptibility patterns, and associated risk factors of Salmonella and Shigella among food handlers. Methodology: A cross-sectional study was conducted from March to August 2018 at Adigrat University student cafeteria, Northern Ethiopia. Data on socio-demographic and associated risk factors were collected using a structured questionnaire. Fresh stool samples were collected from 301 food handlers and transported to Adigrat University Microbiology Laboratory. Bacterial isolation and antimicrobial susceptibility test were performed using standard bacteriological methods. Data analysis was performed using SPSS version 22 and P < 0.05 with a corresponding 95% confidence interval was considered statistically significant. Results: A total of 301 food handlers were included in this study. The majority of study participants were females 265 (88.0 %). About 22 (7.3%) and 11 (3.7%) of food handlers were found to be positive for Salmonella and Shigella respectively. Hand washing after using a bathroom with water only, hand washing after using the bathroom, hand washing after touching dirty materials, hand washing before food handling and fingernails status were significant associated risk factors identified. None of the Salmonella and Shigella isolates were sensitive to ampicillin. On the other hand, low resistance was found for chloramphenicol , ceftriaxone, and ciprofloxacin. Conclusion: The present study revealed that the prevalence of Salmonella and Shigella among food handlers found to be 22 (7.3%) and 11 (3.7%) respectively. Such infected food handlers can contaminate food, drinks and could serve as a source of infection to consumers via the food chain. This indicates that the need for strengthened infection control measures to prevent Salmonella and Shigella transmission in the students’ cafeteria.
The utility of T-SPOT.TB for the diagnosis unconventional pleural tuberculosis is superior to ADA in high prevalence: A perspective analysis of 601 cases
Authors: Yang Xinting , zhang jing , Liang Qingtao , Pan Liping , Duan Hongfei , Yang Yang , Li Hua , Guo Chao , Sun Qi , Jia Hongyan , Du Boping , Wei Rongrong , Xing Aiying , Zhang Zongde , Chen Xiaoyou
Published: February 2020

BACKGROUND Recently, Interferon Gamma Release Assay (IGRA) is still controversial in differentiating tuberculous pleural effusion (TPE), through recommended by World Health Organization (WHO )for identification of latent tuberculosis infection. OBJECTIVES Aim to qualify the diagnostic efficacy for TPE by IGRA in comparison to Adenosine deaminase(ADA), to clarify its appropriate scene in clinical diagnosis. METHODS A prospective, single-centre study including all suspected pleural effusion patients consecutively from June 2015 to October 2018. Through receiver operating characteristic (ROC) curves, all enrolled participants were determined technical cut-off and the utility of IGRA(T-SPOT)for pleural fluid(PF). Obtain the independent risk factors by logistic regression analysis for TPE, and evaluate the performance of T-SPOT stratified by risk factors, in comparison to ADA. RESULTS A total of 601 individuals were consecutively recruited. The maximum of early secretory antigenic target-6 (ESAT-6) and culture filtrate protein-10 (CFP-10) in PF T-SPOT had the best diagnostic efficiency in our study, with a sensitivity of 83.0% and a specificity of 83.1%, corresponding cut-off value is 466, which was equal to ADA(0.885 vs 0.887, P=0.957) and superior than in PB; Among the TPE patients with low ADA(<40 IU/L), the sensitivity and specificity of PF T-SPOT was still 87.9%, 90.5% respectively. The utility of ADA was negative related to age ascents, but PF T-SPOT had steady performance at any age-stage. The age (<45 yrs; odds ratio (OR) 5.61), gender (male; OR 2.7) and body mass index (BMI)(<22; OR 1.93) was independently associated with the risk of TB by multivariate logistic regression analysis. Stratified by risk factors, notably the PF T-SPOT had superior sensitivity(76.5% vs. 23.5%,P=0.016) than ADA meanwhile had the non-inferior specificity(84.4% vs. 96.9%, P=0.370). CONCLUSIONS In conclusion, the overall potency of PF T-SPOT assay is equal to ADA for diagnosing TPE. In addition, PF T-SPOT can effectively discriminate the TPE patients whose ADA lower than 40IU/L, and extremely superior to ADA in unconventional TPE patients(age>45yrs, female or BMI<22). PF T-SPOT assay is an extremely good choice to supplement ADA to diagnose TPE.
CapsNets continuing the convolutional quest
Authors: Diefenbacher Sascha , Frost Hermann , Kasieczka Gregor , Plehn Tilman , Thompson Jennifer
Published: February 2020

Capsule networks are ideal tools to combine event-level and subjet information at the LHC. After benchmarking our capsule network against standard convolutional networks, we show how multi-class capsules extract a resonance decaying to top quarks from both, QCD di-jet and the top continuum backgrounds. We then show how its results can be easily interpreted. Finally, we use associated top-Higgs production to demonstrate that capsule networks can work on overlaying images to go beyond calorimeter information.
Scrambling for higher metrics in the Journal Impact Factor bubble period: a real-world problem in science management and its implications
Authors: Tran Trung , Hoang Khanh-Linh , La Viet-Phuong , Ho Manh-Toan , Vuong Quan-Hoang
Published: February 2020

Universities and funders in many countries have been using Journal Impact Factor (JIF) as an indicator for research and grant assessment despite its controversial nature as a statistical representation of scientific quality. This study investigates how the changes of JIF over the years can affect its role in research evaluation and science management by using JIF data from annual Journal Citation Reports (JCR) to illustrate the changes. The descriptive statistics find out an increase in the median JIF for the top 50 journals in the JCR, from 29.300 in 2017 to 33.162 in 2019. Moreover, on average, elite journal families have up to 27 journals in the top 50. In the group of journals with a JIF of lower than 1, the proportion has shrunk by 14.53% in the 2015–2019 period. The findings suggest a potential ‘JIF bubble period’ that science policymaker, university, public fund managers, and other stakeholders should pay more attention to JIF as a criterion for quality assessment to ensure more efficient science management.
Hydraulic characteristics of the aeration basin in a ski-jump-step spillway
Authors: Qian Shangtuo , Wu Jianhua
Published: February 2020

The ski-jump-step spillway was designed using a ski-jump and an aeration basin to effectively pre-aerate flow in a stepped spillway. A new experimental study of the hydraulic characteristics of aeration basins was conducted to better understanding their pre-aeration properties and mechanisms. The plunge-pool patterns of aeration basins were classified into partially aerated, fully aerated, and vortex expelled, with increasing unit discharge. Relations between the distributions of the time-averaged pressure and the air concentration of the plunge-pools suggested that the ski-jump jet impact and the recirculating vortices are the main causes of plunge-pool air entrainment. Based on the export cross-section of the aeration basins, the bottom air concentrations remained greater than 3.0%. The sidewall air concentrations were greater than 7.5% and followed a logarithmic distribution in the vertical direction, demonstrating that the export flow attains a completely aerated state without any blackwater zones. In addition, increasing the aeration basin length was found to prevent the occurrence of a vortex expelled plunge-pool, thus promoting the appropriate pre-aeration effect under large unit discharges.
Investigation of chlorine wall decay in an old, decommissioned metallic pipe using a pipe section reactor
Authors: Tonev R. , Dimova G.
Published: February 2020

The study investigates the kinetics of free chlorine depletion in tap water from the Sofia distribution network. The overall decay rates, the bulk reaction rate coefficient, the wall reaction rate coefficient and the influence of mass transfer have been determined in a laboratory pipe section reactor (PSR), testing an old decommissioned metallic pipe. In total, 23 series of experiments were performed under different initial free chlorine concentrations and different hydraulic conditions. The applicability of different chlorine decay mathematical models has been investigated. A new model was proposed, combining zero order bulk reactions and first order wall reactions, describing the laboratory results with Nash-Sutcliffe efficiency coefficients over 0.99. The obtained values for the wall reaction coefficient vary in the range 0.008–0.030 m/h, decreasing exponentially with increasing initial chlorine concentration.