bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lifelog Data-Based Prediction Model of Digital Health Care App Customer Churn: Retrospective Observational Study
Authors: Kwon Hongwook , Kim Ho Heon , An Jaeil , Lee Jae-Ho , Park Yu Rang 
Published: November 2020

Background
Customer churn is the rate at which customers stop doing business with an entity. In the field of digital health care, user churn prediction is important not only in terms of company revenue but also for improving the health of users. Churn prediction has been previously studied, but most studies applied time-invariant model structures and used structured data. However, additional unstructured data have become available; therefore, it has become essential to process daily time-series log data for churn predictions.

Objective
We aimed to apply a recurrent neural network structure to accept time-series patterns using lifelog data and text message data to predict the churn of digital health care users.

Methods
This study was based on the use data of a digital health care app that provides interactive messages with human coaches regarding food, exercise, and weight logs. Among the users in Korea who enrolled between January 1, 2017 and January 1, 2019, we defined churn users according to the following criteria: users who received a refund before the paid program ended and users who received a refund 7 days after the trial period. We used long short-term memory with a masking layer to receive sequence data with different lengths. We also performed topic modeling to vectorize text messages. To interpret the contributions of each variable to model predictions, we used integrated gradients, which is an attribution method.

Results
A total of 1868 eligible users were included in this study. The final performance of churn prediction was an F1 score of 0.89; that score decreased by 0.12 when the data of the final week were excluded (F1 score 0.77). Additionally, when text data were included, the mean predicted performance increased by approximately 0.085 at every time point. Steps per day had the largest contribution (0.1085). Among the topic variables, poor habits (eg, drinking alcohol, overeating, and late-night eating) showed the largest contribution (0.0875).

Conclusions
The model with a recurrent neural network architecture that used log data and message data demonstrated high performance for churn classification. Additionally, the analysis of the contribution of the variables is expected to help identify signs of user churn in advance and improve the adherence in digital health care.
Using Structural Equation Modelling in Routine Clinical Data on Diabetes and Depression: Observational Cohort Study
Authors: Ronaldson Amy , Freestone Mark , Zhang Haoyuan , Marsh William , Bhui Kamaldeep 
Published: November 2020

Background
Large data sets comprising routine clinical data are becoming increasingly available for use in health research. These data sets contain many clinical variables that might not lend themselves to use in research. Structural equation modelling (SEM) is a statistical technique that might allow for the creation of “research-friendly” clinical constructs from these routine clinical variables and therefore could be an appropriate analytic method to apply more widely to routine clinical data.

Objective
SEM was applied to a large data set of routine clinical data developed in East London to model well-established clinical associations. Depression is common among patients with type 2 diabetes, and is associated with poor diabetic control, increased diabetic complications, increased health service utilization, and increased health care costs. Evidence from trial data suggests that integrating psychological treatment into diabetes care can improve health status and reduce costs. Attempting to model these known associations using SEM will test the utility of this technique in routine clinical data sets.

Methods
Data were cleaned extensively prior to analysis. SEM was used to investigate associations between depression, diabetic control, diabetic care, mental health treatment, and Accident & Emergency (A&E) use in patients with type 2 diabetes. The creation of the latent variables and the direction of association between latent variables in the model was based upon established clinical knowledge.

Results
The results provided partial support for the application of SEM to routine clinical data. Overall, 19% (3106/16,353) of patients with type 2 diabetes had received a diagnosis of depression. In line with known clinical associations, depression was associated with worse diabetic control (β=.034, P<.001) and increased A&E use (β=.071, P<.001). However, contrary to expectation, worse diabetic control was associated with lower A&E use (β=–.055, P<.001) and receipt of mental health treatment did not impact upon diabetic control (P=.39). Receipt of diabetes care was associated with better diabetic control (β=–.072, P<.001), having depression (β=.018, P=.007), and receiving mental health treatment (β=.046, P<.001), which might suggest that comprehensive integrated care packages are being delivered in East London.

Conclusions
Some established clinical associations were successfully modelled in a sample of patients with type 2 diabetes in a way that made clinical sense, providing partial evidence for the utility of SEM in routine clinical data. Several issues relating to data quality emerged. Data improvement would have likely enhanced the utility of SEM in this data set.
Real-time Mental Health Impact of the COVID-19 Pandemic on College Students: Ecological Momentary Assessment Study
Authors: Kleiman Evan M , Yeager April L , Grove Jeremy L , Kellerman John K , Kim Joanne S 
Published: November 2020

Background
College students’ mental health may be disproportionally affected by the COVID-19 pandemic because of the abrupt shift off campus and subsequent loss of a social network and potential long-term impact on job prospects.

Objective
We sought to assess the nature of COVID-19’s mental health impact among a sample of undergraduates who were experiencing the pandemic as it occurred in real time.

Methods
In total, 140 college students completed smartphone-based ecological momentary assessments of anxiety and optimism related to COVID-19 and other generic mental health variables 6 times daily.

Results
Participants completed >23,750 surveys. Overall, >75% of these surveys indicated at least some level of anxiety about COVID-19. On average, the proportion of responses each day at the highest levels of anxiety about COVID-19 was 7 times greater than the proportion of responses at the highest levels of non–COVID-19–specific anxiety. Structural change analyses indicated a significant downward trend in COVID-19 anxiety after the first week of June, but even at the lowest point, >15% of the participants in the sample still reported high levels of COVID-19 anxiety each day. Participants felt more anxious about COVID-19 on days when the number of new cases and deaths due to COVID-19 were higher. When participants felt anxious about COVID-19, they also felt sad, anxious (in general), and had a greater desire to drink and use drugs. Participants felt more optimistic about COVID-19 when they received more support from others and from their university.

Conclusions
This study demonstrated the widespread mental health impact that COVID-19 has had on college students.
Influence of trans-polyoctylene rubber content on styrene-butadiene rubber properties
Authors: Macúrik Patrik , Anyszka Rafal , Hudec Ivan , Malčeková Terézia , Kruželák Ján 
Published: November 2020

Abstract
The study was focused on the investigation of trans-polyoctylene (TOR) influence on cross-linking as well as mechanical and rheological properties of rubber compounds based on styrene-butadiene rubber (SBR). SBR was compounded with different proportions of TOR in the concentration range from 0 to 30 phr. Integration of TOR into rubber leads to the prolongation of the optimum curing time and scorch time and thus the decrease of the curing rate. Higher content of TOR led to less viscous rubber due to the plasticizing effect. Cross-link density of vulcanizates was reduced, which correlates with higher elongation at break. Tensile strength and hardness of vulcanizates increased with the increasing TOR content, probably due to the increasing amount of the crystalline phase.
Sample matrix influence on microdrop hold-up in single drop microextraction
Authors: Kubasová Nikola , Zichová Silvia , Brisudová Adriána , Hrouzková Svetlana 
Published: November 2020

Abstract
Single drop microextraction has become a widespread liquid/liquid microextraction technique owing to its simplicity, high preconcentration factor and low consumption of organic solvents in the extraction due to direct introduction of the very low volume of extract into the analytical system. Crucial features ensuring excellent repeatability of single drop microextraction include: solvent volume, solvent type, sample agitation, salts addition, and pH. The influence of sample quality on the microdrop volume and agitation type was studied. Effect of the sample matrix, such as water, acid content samples (orange juice), sample containing alcohol (plum brandy) and protein content sample (milk), on the microdrop hold-up was also investigated. For water analysis, several organic solvents such as chloroform, dichloromethane, tetrachloromethane, tetrachloroethane and chlorobenzene were tested; last three mentioned were suitable for SDME experiments. For milk samples analysis, chlorobenzene microdrop was found to be optimal; advantage of salt addition has been reported. For orange samples, 1:10 dilution was suggested with stable microdrop volumes (toluene) of up to 6 µL for lower stirring rates (100 rpm and 250 rpm). For alcohol-content samples, the change of alcohol percentage of real-life samples had to be considered. A strong influence of the matrix quality on the microdrop stability has been proven.
Determination of biological markers of organic substances in sediment and soil samples by gas chromatography
Authors: Koljančić Nemanja , Vyviurska Olga , Balaban Milica , Špánik Ivan 
Published: November 2020

Abstract
Once they reach the environment, petroleum hydrocarbons undergo various chemical, physico-chemical and biochemical transformation processes. Organic compounds which are not or are very poorly subject to these processes are thermodynamically the most stable isomers and they are called biological markers (biomarkers). This paper presents the results of the determination of organic substances in twelve samples taken in the area of the city of Banja Luka (Bosnia and Herzegovina). Two soil samples were taken in the Banja Luka city heating plant area and ten river sediment and soil samples were taken in the upper and lower basin of the Vrbas river in the Banja Luka city area. The aim of this study was to determine the biomarkers of oil-type pollutants in contaminated samples as well as the type of organic substances in samples taken near the contaminated area. Assisted solvent extraction was used to isolate the total petroleum hydrocarbons (TPH) from all twelve samples. Fractionation of the extracts into saturated and aromatic hydrocarbon fractions was performed by column chromatography. The fractions were analyzed by gas chromatography-mass spectrometry (GC-MS). On basis of the obtained chromatograms, biomarkers of petroleum pollutants and specific correlation parameters of organic substances in the samples were determined. The dominance of n-alkanes with odd C atoms as well as the presence of an unresolved complex mixture (UCM) on chromatograms of saturated and aromatic hydrocarbons showed the presence of anthropogenic organic substances of petroleum origin in the analyzed samples. Based on the obtained chromatograms, it can be concluded that microbial degradation of hydrocarbons in all samples occurred.
Control of heat exchangers in series using neural network predictive controllers
Authors: Vasičkaninová Anna , Bakošová Monika , Mészáros Alajos 
Published: November 2020

Abstract
The paper reveals three applications of neural network predictive control (NNPC) to a system of four heat exchangers (HEs) in series with counterflow configuration to save energy expressed by cooling water in the system of HEs cooling the distillation product. Neural networks (NNs) are used at first in conventional NNPC and subsequently, neural network predictive controllers (NNPCLs) are employed as a master controller in a cascade control, and as a feedback controller in the control system with disturbance measurement. Neural-network-predictive-control-based (NNPC-based) feedback control systems are compared with PI controller based feedback control loop. Series of simulation experiments were done and the results showed that using NNPC-based cascade control reduced cooling water consumption. This control system also significantly reduced the settling time and overshoots in the control responses and provided the best assessed integral quality criteria compared to other control systems. NNPC-based cascade control can also be interesting for industrial use. Generally, simulation results proved that NNPC-based control systems are promising means for the improvement of HEs control and achievement of energy saving.
Non-Invasive Ventilation in a Non-Standard Setting – Is it Safe to Ventilate Outside the ICU?
Authors: Boyadzhieva I. , Kovacheva M. , Bektashev D. , Mekov E. 
Published: November 2020

Abstract
Non-invasive ventilation (NIV) is considered a fundamental method in treating patients with various disorders, requiring respiratory support. Often the lack of beds in the intensive care unit (ICU) and the concomitant medical conditions, which refer patients as unsuitable for aggressive treatment in the ICU, highlight the need of NIV application in general non-monitored wards and unusual settings – most commonly emergency departments, high-dependency units, pulmonary wards, and even ambulances. Recent studies suggest faster improvement of all physiological variables, reduced intubation rates, postoperative pulmonary complications and hospital mortality with better outcome and quality of life by early well-monitored ward-based NIV compared to standard medical therapy in patients with exacerbation of a chronic obstructive pulmonary disease, after a surgical procedure or acute hypoxemic respiratory failure in hematologic malignancies. NIV is a ceiling of treatment and a comfort measure in many patients with do-not-intubate orders due to terminal illnesses. NIV is beneficial only by proper administration with appropriate monitoring and screening for early NIV failure. Successful NIV application in a ward requires a well-equipped area and adequately trained multidisciplinary team. It could be initiated not only by attending physicians, respiratory technicians, and nurses but also by medical emergency teams. Ward-based NIV is supposed to be more cost-effective than NIV in the ICU, but further investigation is required to establish the safety and efficacy in hospital wards with a low nurse to patient ratio.
Random inverse packet information and its acquisition
Authors: Yu Xiuqing , Xu Fengsheng 
Published: November 2020

Abstract
Packet sets and inverse packet sets are two kinds of novel mathematical tools to analyze dynamic information systems. With advances in inverse packet sets, random inverse packet information is proposed by introducing random characteristics into inverse packet sets. Hence, random inverse packet information has dynamic and random characteristics, and is an extended form of inverse packet sets. Furthermore, random feature, dynamic feature, and identification relation about the random inverse packet information are discussed. Finally, based on the above theory, an instance is used to illustrate the applications of intelligent acquisition of investment information.
10-Year Journey Through Brain Gliomas: Case Report
Authors: Cîndea Cosmin-Nicodim , Săceleanu Adriana 
Published: November 2020

Abstract
We present the case of a 28-year-old doctor who was diagnosed in 2009 with grade II oligodendroglioma. In the next 10 years he underwent 4 surgeries, passing in turn through 3 different types of cerebral gliomas: grade II oligodendroglioma, grade III oligoastrocytoma and IDH Wild-Type glioblastoma. In the spirit of the surgical resection limited by the preservation of the function, he was able to practice his medical profession until the last months of his life. Life expectancy at the time of diagnosis complied with all the statistical data. Although the etiology, pathophysiology and treatment of cerebral gliomas is still full of unknowns, knowing our limits we can provide a good quality of life for our patients.
From Selenium to Selenoproteins and their Role - Minireview
Authors: Caţianis Alexandra Gabriela , Virgolici Bogdana , Dogaru Beatrice Carmen , Virgolici Horia , Mohora Maria 
Published: November 2020

Abstract
Selenium (SE) is an essential micronutrient fulfilling a number of biological roles, being integrated as selenocysteine in the primary structure of certain selenoproteins. The Selenocysteine is synthesized and inserted into proteins during the translational process of the RNAm by a mechanism which involves converting a stop codon for certain proteins into a meaningful codon. Only 25 genes encoding selenocysteine-incorporating proteins have been identified in the human genome. The selenoprotein families including glutathione peroxidase, iodothyronine deiodinase and thioredoxin reductases are known as enzymes engaged in redox processes. The selenoprotein P (SEPP1) is a hepatokine produced by the liver, an extracellular glycoprotein, which is not part of these families. The purpose of this Article is to present the form of distribution of selenium and its physiological role in the body.
Occlusal Surface Achieved Using the Stamp Technique
Authors: Ionaş Mona , Dăncilă Adela 
Published: November 2020

Abstract
Dental occlusion can be restored through preparation, modelling, occlusal adjustment and finishing or by reproducing the final future tooth surface. The micro-brush stamp technique is a new technique used in direct restorations. The purpose of this paper is to present a fast way of restoring the occlusal surface of a tooth when a previous correct functional impression of the surface exists. We will approach, step by step, the occlusal dental tissue reconstruction using a dental flowable composite and a microbrush to get a stamp of the occlusal surface in order to achieve precise occlusal topography.
Telepsychiatry in the Romanian Health System During COVID-19 Pandemic
Authors: Băcilă Ciprian , Anghel Claudia 
Published: November 2020

Abstract
With the covid-19 pandemic and the related restrictions to reduce the spread of the virus, the interaction between doctor and patient has changed, especially in the outpatients department. Thus, the need for remote consultations also appeared in the Romanian health system, especially in the psychiatric one. Although in other countries psychiatrists were familiar with this form of consultation, for Romanian psychiatrists, who were not trained either in residency or during medical school, it was a great challenge. If until March 2020 the patient’s consultation had to be performed only in the physical presence of a doctor, once the COVID-19 pandemic appeared, the Romanian government and the president, through the legislative acts issued, provided a legal framework for conducting this remote consultations. With the advent of telepsychiatry, discussions arose in the psychiatric community about the advantages and disadvantages of this type of consultation.
Growth performance and physiological responses of helmeted guinea fowl (Numida meleagris) to different stocking densities in humid tropical environment
Authors: Oke Oyegunle Emmanuel , Oso Abimbola , Iyasere Oluwaseun Serah , Adebowale Tolulope , Akanji Tolulope , Odusami Odutola , Udehi Sandra , Daramola James Olamitibo 
Published: November 2020

Abstract
Commercialisation of helmeted guinea fowl production in Africa is still in its rudimentary stage and there is a dearth of information on the optimal stocking density of the birds. This study was conducted to evaluate the effect of stocking density on the physiological responses and performance of guinea fowl. A total of 240 indigenous guinea fowl were used for this study. The birds were weighed and assigned to different stocking densities of 14, 16, 18 and 20 birds/m2 (SD1, SD2, SD3 and SD4, respectively) at four weeks of age. Feed and water were provided ad libitum. Data were collected on growth performance, haematochemical profile and plasma triiodothyronine of the birds. The results showed that from the 7th to the 13th week, birds stocked at 14 and 16 birds/m2 were significantly (P < 0.05) heavier than birds stocked at 18 and 20 birds/m2, while at weeks 14 and 15, body weight of the birds was in the order 14 birds / m2 > 16 birds / m2 > 18 birds/m2 > 20 birds/m2. Feed conversion ratios of the birds increased with stocking densities. Heterophil/lymphocyte ratio significantly increased with stocking density. It was concluded that stocking density of helmeted guinea fowl higher than 16 birds/m2 adversely affected growth performance and welfare of the birds.
Physicochemical analysis of water and sediments of Usuma Dam, Abuja, Nigeria
Authors: Ilechukwu Ifenna , Olusina Tolulope Abisola , Echeta Odinaka Chidinma 
Published: November 2020

Abstract
Usuma Dam is the major source of potable water in the Federal Capital Territory, Abuja, Nigeria. The physicochemical properties of water and sediment of the dam was assessed in this study to determine its quality. Electrical conductivity, pH, nitrate, phosphate, total dissolved solids, total suspended solids, turbidity, dissolved oxygen, biochemical oxygen demand, chemical oxygen demand, chloride, total hardness, phosphate, nitrate and sulfate were determined in the water samples. Total organic matter, total organic carbon and particle size were among the parameters analyzed in sediments. The parameters were within recommended limits except for biochemical oxygen demand and chemical oxygen demand which were more than the recommended limit of 10 mg/L and 30 mg/L respectively. The total organic matter and the total organic carbon in the sediment samples were between 1.56±0.27 – 2.85±0.20 % and 0.13±0.03 – 0.96±0.03 % respectively. The particle size was in the following order: sand > silt > clay. The results of this study confirmed the presence of high organic and inorganic matter in the dam from non-point pollution sources occasioned by storm water from poorly planned settlements around the dam and runoffs from agricultural practices.
Nutritional Composition of Oven Dried Eggs Produced from Isa-Brown Hens Fed Composite Leaf Meal-Based Diets
Authors: Adegbenro Muyiwa 
Published: November 2020

Abstract
The study investigated effects of diet compositions on nutrient composition of oven dried eggs. Eggs were obtained from birds fed composite leaf meal (CLM) and separated as egg white, egg yolk and whole egg. The separated portions and whole egg were homogenized separately. The samples were oven-dried at 40°C and allowed to cool. The different portions of the egg flakes were milled, sieved and proximate analysis was done. For the egg white, highest crude protein (71.83%) was recorded in egg from birds fed 5% CLM and lowest (62.88%) in egg from birds fed 0% CLM. For egg yolk, highest carbohydrate 38.66% was observed in egg from bird fed 0% CLM and lowest 25.50% in egg from bird fed 5% CLM. Food energy varied; 528.02g/cal to 544.56g/cal in egg obtained from bird fed 2% and 1% CLM, respectively. The crude protein of the whole egg varied; 48.40% (0%) - 56.15% (5% CLM). From the results, it could be concluded that the nutrient composition of the egg white, egg yolk and whole egg were affected by the levels of CLM in the diet.