bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hacia un modelo educativo para el emprendimiento
Authors: Segura-Barón Ulises , Novoa-Matallana Henry Alberto , Burbano-Pedraza Maria Del Cielo 
Published: February 2020

Rev.esc.adm.neg
Con base en las consideraciones teóricas y conceptuales, la visión desde la investigación en emprendimiento, la revisión de las condiciones institucionales y el análisis de relaciones entre variables en este tema, se elaboró la propuesta un modelo piloto de emprendimiento dinámico e innovador el cual se presenta a partir de un eje articulador denominado Centro de Emprendimiento para la Universidad Piloto de Colombia, seccional Alto Magdalena.
El enfoque metodológico da cuenta de triangulación de información cuantitativa y cualitativa, que inició con una revisión documental sobre la normatividad vigente acerca del potencial que la educación y la investigación tienen para el emprendimiento, así como su articulación con la estructura determinada por el Estado y las necesidades existentes en lo relativo a transferencia del conocimiento desde la universidad al sector productivo y social y prosiguió con el desarrollo de procesos de discusión institucional, contrastando la información recabada con las percepciones de los actores del proceso.
En este marco se determinaron las variables que compusieron la línea de investigación, las cuales fueron: el emprendedor, el entorno y las relaciones existentes entre el emprendedor y el entorno por las acciones de los actos de emprendimiento.
Así las cosas, se concluye que resulta evidente la importancia de fortalecer la investigación en emprendimiento mejorando sus niveles cuantitativos y cualitativos y definiendo un derrotero o argumentación real y significativa para sopor tar todo tipo de políticas y proyectos en apoyo al tema, sobre la base de la triada fundamental de desarrollo: universidad, empresa y Estado.
Injectivity of Multiple Slugs in Surfactant Alternating Gas Foam EOR: A CT Scan Study
Authors: Gong Jiakun , Vincent-Bonnieu Sebastien , Kamarul Bahrim Ridhwan Z. , Che Mamat Che A. N. B. , Tewari Raj D. , Mahamad Amir Mohammad I. , Groenenboom Jeroen , Farajzadeh Rouhollah , Rossen William R. 
Published: February 2020

SummaryA surfactant alternating gas (SAG) process is often the injection method for foam, on the basis of its improved injectivity over direct foam injection. In a previous study, we reported coreflood experiments on liquid injectivity after foam flooding and liquid injectivity after injection of a gas slug following steady-state foam. Results showed that a period of gas injection is important for the subsequent liquid injectivity. However, the effects of multiple gas and liquid slugs were not explored.In this paper, we present a coreflood study of injectivities of multiple gas and liquid slugs in an SAG process in a field core. Nitrogen and surfactant solution are either coinjected or injected separately into the sandstone core sample. The experiments are conducted at an elevated temperature of 90°C with a backpressure of 40 bar. Differential pressures are measured to quantify gas and liquid injectivities. Computed tomography (CT) scanning is applied to relate water saturation to mobility.During the injection of a large gas slug following foam, a bank in which foam completely collapses or greatly weakens forms near the inlet and propagates slowly downstream. During the subsequent period of liquid injection, liquid flows through the collapsed-foam bank much more easily than further downstream. Beyond the collapsed-foam region, liquid first imbibes into the whole cross section. In this region, liquid flows mainly through a finger of high liquid saturation. Our CT results suggest a revision of our earlier interpretation; the process of gas dissolution does not merely follow fingering but is evidently directly involved in the fingering process.Our results suggest that, in radial flow, the small region of foam collapse very near the well greatly improves injectivity. The subsequent gas and liquid slugs behave near the wellbore, affecting injectivity, in a way similar to the first slugs. Thus, the behavior and modeling of the first gas slug and first subsequent liquid slug is representative of near-well behavior in an SAG process. The trends observed in our previous work are reproduced in a low-permeability field core.
Surface-Modified Graphite Nanoplatelets To Enhance Cement Sheath Durability
Authors: Tabatabaei Maryam , Dahi Taleghani Arash , Alem Nasim 
Published: February 2020

Summary
We propose a novel cement additive made of graphite nanoplatelets (GNPs) for improved hydraulic isolation and durability of oil and gas wells. The primary role of the cement sheath, which is zonal isolation, can be significantly affected by the permeability of set cement (hardened cement slurry). On one hand, it is the inherent microstructural defects of cement, including pores and microcracks, that results in the intrinsic permeability of cement, and on the other hand, cracking, micro-annuli, or other flow paths developed through the disturbed cement by connecting the pre-existing microstructural defects determine the equivalent permeability of set cement. The purpose of this research is containing or at least minimizing the intrinsic and developed flow paths through the cementitious matrix with the help of surface-modified GNPs. GNPs possess high surface area to volume ratios. In this study, we focus on the effect of surface-modified GNPs on the overall mechanical properties of both cement slurry and hardened cement slurry affecting the permeability of cement. We present two dispersion methods on the basis of physical and chemical treatments of the surface properties of GNPs. The efficiency of proposed methods on the overall properties of the cement is examined before and after its setting. To mimic downhole conditions, cement slurries are cured at 3,000 psi and 190°F for 24 hours. Also, some experiments were repeated under the pressure and temperature conditions up to 5,160 psi and 126°F, respectively, to examine pumpability and behavior of cement slurry at bottomhole conditions. To examine the role of spatial distribution of GNPs on the hardened cement nanocomposite, samples with different concentrations of GNPs were tested. We investigated the effect of modified GNPs on the unconfined compressive strength (UCS), shear bond strength, thickening time, rheological characteristics, and the free fluid content. We measured zero free fluid at room temperature for different concentrations of GNPs, demonstrating uniform dispersion of nanoparticles within the cement matrix. On the other hand, the squeeze of water out of the lower parts of the cement slurry and its upward migration can develop preferential paths for oil and gas migration. Therefore, eliminating the above-mentioned water separation can enhance cement sealing properties. We found that an optimum 0.2 vol% concentration of acid-functionalized GNPs improves the compressive and the shear bond strength of the prepared cement by approximately 42 and 175% as compared to the plain cement, respectively.
Genome-wide identification and expression analysis of PUB genes in cotton
Authors: Lu Xuke , Shu Na , Wang Delong , Wang Junjuan , Chen Xiugui , Zhang Binglei , Wang Shuai , Guo Lixue , Chen Chao , Ye Wuwei 
Published: February 2020

Abstract
Background: The U-box gene encodes a ubiquitin ligase that contain U-box domain. The plant U-box gene (PUB) plays an important role in the response to stresses, but few reports about PUBs in cotton were available. Therefore research on PUBs is of great importance and a necessity when studying the mechanisms of stress- tolerance in cotton.Results: In this study, we identified 93, 96, 185 and 208 PUBs from four sequenced cotton species G. raimondii (D5), G. arboreum (A2), G. hirsutum (AD1) and G. barbadense (AD2), respectively. Prediction analysis of subcellular localization showed that the PUBs in cotton were widely localized in cells, but primarily in the nucleus. The PUBs in cotton were classified into six subfamilies (A-F) on the basis of phylogenetic analysis, which was testified by the analysis of conserved motifs and exon-intron structures. Chromosomal localization analysis showed that cotton PUBs were unevenly anchored on all chromosomes, varying from 1 to 14 per chromosome. Through multiple sequence alignment analysis, 3 tandem duplications and 28 segmental duplications in cotton genome D5, 2 tandem duplications and 25 segmental duplications in A2, and 143 homologous gene pairs in A2 and D5 were found; however no tandem duplications in A2 or D5 were found. Additionally, 105, 14 and 17 homologous gene pairs were found in the intra-subgenome of At and Dt, At sub-genome and Dt sub-genome of G. hirsutum, respectively. Functional analysis of GhPUB85A and GhPUB45D showed that these genes positively responded to abiotic stresses, but the expression patterns were different. In addition, although the expression levels of these two homologous genes were similar, their contributions were different when responding to stresses, specifically showing different responses to abiotic stresses and functional differences between the two subgenomes of G. hirsutum. Conclusion: This study reported the genome-wide identification, structure, evolution and expression analysis of PUBs in cotton, and the results showed that the PUBs were highly conserved throughout the evolutionary history of cotton. All PUB genes were involved in the response to abiotic stresses (including salt, drought, hot and cold) to varying degrees.
Genome-wide association studies of Shigella spp. and Enteroinvasive Escherichia coli isolates demonstrate an absence of genetic markers for prediction of disease severity
Authors: Hendriks Amber C. A. , Reubsaet Frans A.G. , Kooistra A.M.D. (Mirjam) , Rossen John W. A. , Dutilh Bas E. , Zomer Aldert L. , Beld Maaike J. C. van den 
Published: February 2020

Abstract
Background: We investigated the association of symptoms and disease severity of shigellosis patients with genetic determinants of infecting Shigella and entero-invasive Escherichia coli (EIEC), because determinants that predict disease outcome per individual patient could be used to prioritize control measures. For this purpose, genome wide association studies (GWAS) were performed using presence or absence of single genes, combinations of genes, and k-mers. All genetic variants were derived from draft genome sequences of isolates from a multicenter cross-sectional study conducted in the Netherlands during 2016 and 2017. Clinical data of patients consisting of binary/dichotomous representation of symptoms and their calculated severity scores were also available from this study. To verify the suitability of the methods used, the genetic differences between the genera Shigella and Escherichia were used as control. Results: The isolates obtained were representative of the population structure encountered in other Western European countries. No association was found between single genes or combinations of genes and separate symptoms or disease severity scores. Our benchmark characteristic, genus, resulted in eight associated genes and >3,000,000 k-mers, indicating adequate performance of the algorithms used. Conclusions: To conclude, using several microbial GWAS methods, genetic variants in Shigella spp. and EIEC that can predict specific symptoms or a more severe course of disease were not identified, suggesting that disease severity of shigellosis is dependent on other factors than the genetic variation of the infecting bacteria. Specific genes or gene fragments of isolates from patients are unsuitable to predict outcomes and cannot be used for development, prioritization and optimization of guidelines for control measures of shigellosis or infections with EIEC.
Prevalence and Associated Factors of Urinary Incontinence in Women Living in China: A Literature Review
Authors: Xue Kaikai , Palmer Mary H , Zhou Fang 
Published: February 2020

Abstract
Background: This review of studies on urinary incontinence (UI) was focused primarily on UI prevalence and associated factors across the adult lifecourse of Chinese women. UI is a urologic symptom that can have a significant impact on women's physical and mental health and quality of life. Although researchers from many countries have reported prevalence rates and associated factors for UI, little is known about the prevalence of UI in China’s large female population. Language may act as a barrier to the inclusion of published studies in English-language journals. To overcome this barrier and to add to the global knowledge base about UI in women, the authors reviewed and discussed findings from epidemiological studies published in China and in Chinese language.
Methods: The authors retrieved research studies from the five databases using the following search terms: "Subject: (Female) * Subject: (Urinary incontinence) * Subject: (Prevalence) * Date: 2013-2019". The authors used PubMed to search English-language studies published in Chinese journals on UI in Chinese women.
Results: This literature review includes 48 articles published between January 2013 and December 2019. The overall UI prevalence rates reported in adult Chinese women ranged from 8.7% to 69.8%. For women aged 17 to 40 years, 41 to 59 years, and 60 years and older, prevalence rates ranged from 2.6% to 30.0%, 8.7% to 47.7%, and 16.9% to 61.6%, respectively. Significant associated factors for overall UI included age, body mass index, constipation, parity, and menopause. Despite the 17 to 40 age range being peak reproductive years, the literature revealed little focus on UI prevalence rates. For women aged 41 to 59 years, the main associated factors included those related to pregnancy and gynecologic diseases. For women 60 years and older, chronic diseases represented most of the associated factors.
Conclusions: About 43 to 349 million Chinese women may experience UI. Many of the identified associated factors could be mitigated to reduce UI incidence and prevalence rates. Little is known about the prevalence rates and associated factors for UI among young Chinese women. Future research should investigate UI in young women to improve bladder health across their lifecourse.
Reliability and correlation of mixture cell correction in methylomic and transcriptomic blood data
Authors: Chaumette Boris , Kebir Oussama , Dion Patrick A. , Rouleau Guy A. , Krebs Marie-Odile 
Published: February 2020

Abstract
Objectives : The number of DNA methylome and RNA transcriptome studies is growing, but investigators have to consider the cell type composition of tissues used. In blood samples, the data reflect the picture of a mixture of different cells. Specialized algorithms can address the cell-type heterogeneity issue. We tested if these corrections are correlated between two heterogeneous datasets. Results : We used methylome and transcriptome datasets derived from a cohort of ten individuals whose blood was sampled at two different timepoints. We examined how the cell composition derived from these omics correlated with each other using “CIBERSORT” for the transcriptome and “EstimateCellCounts function” for the methylome. The correlation coefficients between the two omic datasets ranged from 0.45 to 0.81 but correlations were minimal between two different timepoints. Our results suggest that a posteriori correction of a mixture of cells present in blood samples is reliable. Using an omic dataset to correct a second dataset for relative fractions of cells appears to be applicable, but only when the samples are simultaneously collected. This could be beneficial when there are difficulties to control the cell types in the second dataset, even when the sample size is limited.
Diagnostic efficacy of double-balloon enteroscopy in patients with suspected isolated small bowel Crohn’s disease
Authors: Huang Zihan , Liu Xiang , Yang Fei , Wang Guoxin , Ge Nan , Wang Sheng , Guo Jintao , Sun Siyu 
Published: February 2020

Abstract
Background: Owing to the development of double-balloon enteroscopy (DBE) and video capsule endoscopy (VCE) in recent years, direct visualization of the entire small intestinal mucosa has become possible. Because of the nonspecific symptoms and the anatomic location of the small bowel, diagnosis of isolated small bowel Crohn’s disease (CD) remains a challenge. The aim of this research was to explore the value of DBE for isolated small bowel CD in situations where routine tests cannot confirm the diagnosis.Methods: This study included patients with suspected isolated small bowel CD who were hospitalized in Shengjing Hospital from April 2014 to June 2018. We included patients presenting with chronic diarrhea, abdominal pain, abdominal mass, perianal lesions, and systemic symptoms including weight loss, fever, and anemia after excluding infection factors. Patients with purely colonic CD were excluded from this cohort. Patients with suspected isolated small bowel CD underwent DBE.Results: In 16/18 patients, pathological findings were detected by DBE. In 12 of the cases, small bowel CD was confirmed. The remaining four patients were diagnosed with small bowel inflammation, duodenal carcinoma, ileum inflammation and small bowel ulcers. However, the diagnosis of CD was confirmed in 14/18 (78%) patients by taking into account the clinical presentation, endoscopic and histological results as well as the experimental treatment. DBE assisted in the diagnosis in 86% (12/14) of the patients.Conclusions: In the diagnosis of small bowel CD, DBE is a helpful tool. Before assessment with DBE, clinical features, colonoscopy, and CT were used to initially assess the intestine. According to the lesions indicated by CT, we chose the most appropriate endoscope insertion route, and combined the endoscopic characteristics and pathological results of DBE to confirm the diagnosis.
Defining the short-term disease recurrence after Loop Electrosurgical Excision Procedure (LEEP)
Authors: Papalia Nicholas , Rohla Amanda , Tang Selphee , Nation Jill G. , Nelson Gregg 
Published: February 2020

Abstract
Background
The goal of cervical cancer screening is to identify dysplastic lesions for subsequent excision in order to prevent invasive disease. There is clinical equipoise, on how to best follow women for disease surveillance after treatment with some Canadian provinces exclusively performing colposcopy and some utilizing HPV testing in addition to cervical cytology. Loop Electrosurgical Excision Procedure (LEEP) is used to treat pre-invasive HPV-mediated disease and patients are typically followed for 12 months after disease excision. This study aims to quantify the prevalence of high-grade disease at the time of the second follow-up colposcopy visit, in a practice setting that utilizes laser ablation in addition to LEEP.
Methods
In a retrospective cohort study, consecutive patient charts were accessed through the electronic medical record system, ARIA, at the Tom Baker Cancer Centre, in Calgary, Alberta, from January 2010 to December 2015. Data was extracted and a REDCap database was used to compile pertinent information from charts meeting inclusion criteria. Descriptive and analytic statistics were performed.
Results
Of the 303 patients identified, 221 patients met inclusion criteria. 86% of these patients met discharge criteria from colposcopy after the second follow up visit. 31 (14%) were seen in a subsequent visit for abnormal findings. Of these, 7 (3.2%) underwent further treatment for high-grade disease (CIN 2/3). Of the 31, 23 (10.6%) had a third – negative – visit, resulting in discharge from colposcopy. One patient had a repeat LEEP for persistent LSIL.
Conclusion
In summary, our data demonstrates a prevalence of 3.2% of high-grade disease at the time of a second colposcopic follow up visit after treatment, in a setting which frequently utilizes laser ablation in combination with LEEP, for large lesions. This recurrence rate is consistent with most published literature on recurrence rates of CIN2/3.
First-trimester maternal serum alpha-fetoprotein is not a good predictor for adverse pregnancy outcomes: a retrospective study of 3325 cases
Authors: Hu Jilin , Zhang Jinman , He Guilin , Zhu Shu , Tang Xinhua , Su Jie , Li Qian , Kong Yamin , Zhu Baosheng 
Published: February 2020

Abstract
Background: It is well known that second-trimester maternal serum alpha-fetoprotein (MS-AFP) is a predictor for adverse pregnancy outcomes (APOs), such as preterm birth, stillbirth, preeclampsia and small for gestational age (SGA). However, it is unknown whether first-trimester MS-AFP is also predictive of APOs. Methods: We retrospectively reviewed the data on the first-trimester MS-AFP levels and pregnancy outcomes of 3325 singleton pregnant women. The cutoff value of 2.5 multiple of the median (MoM) was used to evaluate the risks of APOs regarding MS-AFP. The receiver operating characteristic (ROC) curves were used to evaluate the predictive efficiencies of MS-AFP to these disorders. Results: A total of 181 pregnancies resulted in preterm birth, 32 in stillbirth, 81 in preeclampsia, and 362 in SGA. Compared to women with MS-AFP < 2.5MoM, those with MS-AFP ≥ 2.5MoM had increased risks (odds ratio, 95% confidence interval) of preterm birth (2.53, 1.65~3.88), preeclampsia (3.05, 1.71~5.43) and SGA (1.90, 1.34~2.69), and had an earlier distribution of gestational weeks at delivery (P = 0.004) and a lower distribution of neonatal birth weights (P = 0.000), but the actual between-group differences were minuscule. The areas under ROC curves were 0.572 (P = 0.001), 0.579 (P = 0.015) and 0.565 (P = 0.000) for preterm birth, preeclampsia and SGA, respectively. Subdivisions for the disorders did not obviously improve the performances of MS-AFP. Conclusions: Elevated first-trimester MS-AFP is associated with increased risk of preterm birth, preeclampsia and SGA. However, the predictive efficiencies were low and it is not a good predictor for these APOs.