bluuebunny/crossref_metadata_2025 huggingface dataset:
The Acrosomal Status of Density Purified Spermatozoa Differentiates Men from Couples in IVF and ICSI Treatment and Is Associated with Fecundity
Authors: Norup Pernille Badsberg , Egeberg Palme Dorte L. , Petersen Morten R. , Main Katharina M. , Almstrup Kristian
Published: July 2020

The acrosome of the spermatozoa is required for fertilization and in the raw ejaculate the percentage of viable acrosome-intact spermatozoa, the acrosomal status, is higher among men with good semen quality. Here we investigated if the acrosomal status of the processed semen preparations used at a fertility clinic can also be informative and whether it is associated with fecundity. The acrosomal status was measured by image cytometry on purified semen samples from couples during in vitro fertilization (IVF) (n = 99) and intracytoplasmic sperm injection (ICSI) (n = 107) treatment. Purified frozen-thawed donor samples were also analyzed (n = 199). In purified semen preparations the acrosomal status was significantly higher among sperm donors (p = 5.3 × 10−8) and men from IVF couples (p = 2.2 × 10−5) when compared to men from ICSI couples. A significant difference was also found between female, male and mixed factor infertility (p = 0.003). No association with lifestyle factors was found. In frozen-thawed donor samples, a significant positive (r = 0.16, p = 0.025) association with the number of pregnancies per sold straw was observed together with an area under the curve of 75.3%, when comparing the top and bottom deciles. Our results indicate that the acrosomal status may be a valuable parameter for personalizing fertility treatments and might be a good predictor of pregnancy success among normozoospermic men.
Mastitis While Breastfeeding: Prevention, the Importance of Proper Treatment, and Potential Complications
Authors: Pevzner Miri , Dahan Arik
Published: July 2020

Mastitis is an inflammation in the breast, which may involve a bacterial infection. Breast infection during breastfeeding is a common phenomenon that requires immediate and appropriate treatment. Without proper treatment, inflammation may lead to the cessation of breastfeeding. Another potential complication is the development of an abscess. Based on the nutritional and immunological value of breast milk, the recommendations of the American Academy of Pediatrics (AAP) and the World Health Organization (WHO) is exclusive breastfeeding up to 6 months of age, followed by continued breastfeeding as complementary foods are introduced, with continuation of breastfeeding for 1 year or longer as mutually desired by mother and infanRecent meta-analyses indicate breastfeeding protects against childhood infections, allows for a possible increase in intelligence, and for a reduction in overweight and diabetes. Breastfeeding is beneficial for nursing women as well. It is therefore important to help the mother overcome difficulties such as mastitis and to continue breastfeeding. The choice of a proper treatment and the provision of therapeutic instructions to the patient are crucial for a cure, for a successful duration of breastfeeding, and for preventing complications for mother and baby. In this article, we provide the latest clinical guidelines regarding drug treatment and supportive therapy in mastitis. We also discuss the latest guidelines of candida treatment, as candida infection may develop as a result of antibiotic therapy. Overall, improperly treated mastitis may cause the premature cessation of breastfeeding, and will cause suffering to both mother and baby; giving proper treatment and instructions to the mother are hence of the utmost importance.
The Multidimensional Daily Diary of Fatigue-Fibromyalgia-17 Items (MDF-Fibro-17): Evidence from Validity, Reliability and Transcultural Invariance between Portugal and Brazil
Authors: Álvarez Marcos C. , Albuquerque Maria Luiza L. , Neiva Henrique P. , Cid Luís , Rodrigues Filipe , Teixeira Diogo S. , Monteiro Diogo
Published: July 2020

The Multidimensional Daily Diary of Fatigue-Fibromyalgia-17 (MDF-fibro-17) is an instrument that measures the different components of fibromyalgia-related fatigue symptoms. The current study aims to examine the factor structure of the MDF-fibro-17 in a sample of Portuguese and Brazilian patients diagnosed with fibromyalgia. Additionally, a cross-cultural analysis was carried out on these samples to understand the multidimensional complexity of examining the different dimensions of fatigue in patients with different cultural backgrounds and how fibromyalgia impacts patients with this syndrome. A confirmatory factor analysis was performed to examine the psychometric properties of the measure. Additionally, a multigroup analysis was carried out on the samples of these two cultures to examine measurement invariance. In total, 209 Portuguese women aged between 21 and 75 years (M = 47.44; SD = 10.73) and 429 Brazilians women aged between 16 and 77 years (M = 46.51; SD = 9.24) participated in this study. The results revealed that the measurement model provided an acceptable fit to the data in both the Portuguese and Brazilian samples, also displaying acceptable convergent and discriminant validity. In addition, the model showed acceptable internal consistency and was invariant between cultures. In sum, the MDF-fibro-17 is a valid measure that offers a unique assessment of fatigue symptoms in Portuguese and Brazilian women with fibromyalgia.
Process Data-Based Knowledge Discovery in Additive Manufacturing of Ceramic Materials by Multi-Material Jetting (CerAM MMJ)
Authors: Lang Valentin , Weingarten Steven , Wiemer Hajo , Scheithauer Uwe , Glausch Felix , Johne Robert , Michaelis Alexander , Ihlenfeldt Steffen
Published: July 2020

Multi-material jetting (CerAM MMJ, previously T3DP) enables the additive manufacturing of ceramics, metals, glass and hardmetals, demonstrating comparatively high solid contents of the processed materials. The material is applied drop by drop onto a substrate. The droplets can be adapted to the component to be produced by a large degree of freedom in parameterization. Thus, large volumes can be processed quickly and fine structures can be displayed in detail, based on the droplet size. Data-driven methods are applied to build process knowledge and to contribute to the optimization of CerAM MMJ manufacturing processes. As a basis for the computational exploitation of mass sensor data from the technological process chain for manufacturing a component with CerAM MMJ, a data management plan was developed with the help of an engineering workflow. Focusing on the process step of green part production, droplet structures as intermediate products of 3D generation were described by means of droplet height, droplet circularity, the number of ambient satellite particles, as well as the associated standard deviations. First of all, the weighting of the factors influencing the droplet geometry was determined by means of single factor preliminary tests, in order to be able to reduce the number of factors to be considered in the detailed test series. The identification of key influences (falling time, needle lift, rising time, air supply pressure) permitted an optimization of the droplet geometry according to the introduced target characteristics by means of a design of experiments.
Recurrent Vulvovaginal Candidosis and Cluster Analysis of Clinical Signs and Symptoms: A Laboratory-Based Investigation
Authors: Ignjatović Aleksandra , Arsić-Arsenijević Valentina , Golubović Milan , Đenić Saša , Momčilović Stefan , Trajković Aleksandra , Ranđelović Marina , Ćirić Vojislav , Otašević Suzana
Published: July 2020

Recurrent vulvovaginal candidosis (RVVC) represents a major health problem that significantly affects a patient’s quality of life (QoL). This infection presents with a plethora of clinical manifestation, and this is the first study that carries out a cluster analysis of these signs and symptoms (SS). The goals are to evaluate the distribution of species causing RVVC, their in-vitro susceptibility to antifungals, and the patient’s QoL. Additionally, the clinical characteristics are analyzed using cluster analysis. Prospective analysis of data was performed for women diagnosed with RVVC in the period from January 2016 to December 2019 based on the analysis of data from a single-center’s records. The standard mycological methods and antifungal susceptibility testing were done. Clinical characteristics and QoL were examined by appropriate questions. The cluster analysis was used to identify clusters of SS. A total of 320 women were diagnosed. The dominant species was Candida (C.) albicans. Non-albicans Candida (NAC) yeast was found in 24.4%, and the most common was C. glabrata. Interestingly, Saccharomyces (S.) cerevisiae was detected in 2%. All of the isolated species, except C. parapsilosis and C. kefyr, demonstrated reduced susceptibility to antifungals. We confirmed the emergence of the NAC species and S. cerevisiae with reduced susceptibility to antifungals. Cluster analysis represented by a dendrogram revealed three SS clusters: irritation, uncommon, and discharge, but further studies are needed to examine the relationship between clusters, Candida strains, and outcomes.
Transitions in Journalism—Toward a Semantic-Oriented Technological Framework
Authors: Panagiotidis Kosmas , Veglis Andreas
Published: July 2020

The technologies behind today’s web services, tools, and applications are evolving continually. As a result, the workflows and methods of different business sectors are undergoing constant change. The news industry and journalism are heavily affected by these changes. New technological means for practicing journalism and producing news items are being incorporated in media workflows, challenging well established journalistic norms and practices. The perpetual technological evolution of the web creates a wide range of opportunities. For this reason, both technology companies and media organizations have begun to experiment with semantic web technologies. Our focus in this paper was to discover and define the ways that semantic technologies can contribute to the technological upgrade of everyday journalism. From this perspective, we introduced the term ‘semantic journalism’ and attempted to investigate the transition of journalism to a semantic-oriented technological framework.
Exploring the Potential and Contribution of UNESCO Biosphere Reserves for Landscape Governance and Management in Africa
Authors: Hedden-Dunkhorst Bettina , Schmitt Florian
Published: July 2020

United Nations Educational Scientific and Cultural Organization (UNESCO) Biosphere Reserves strive for a harmonious interaction between humans and nature. As landscapes provide suitable units to mutually address matters of conservation and sustainable development, this study aims to explore the potential and realized contribution of biosphere reserves for landscape governance and management. We emphasize the role of stakeholder participation and cooperation as an overarching condition for integrated landscape approaches. The regional focus is on Africa, where multiple drivers of global and local change currently significantly impact the landscape. The study’s results are based on a literature review, which is complemented by four case studies from the biosphere reserves in Ghana, Malawi, South Africa, and Benin/Togo. Findings show that in biosphere reserves, stakeholder engagement is crucial to gain community acceptance, foster intersectoral cooperation, and provide management with more legitimacy. To strengthen stakeholders’ capacities to mutually achieve conservation and development outcomes, international partnerships and research and education efforts proved to be successful. The flexible biosphere reserve approach to governance, which allows for integration with other land-management approaches, offers a suitable governance model for a landscape. Moreover, the biosphere reserve zonation concept can provide orientation to manage the “multifunctionality” of a landscape and address the associated trade-offs between different stakeholders’ aspirations.
Quasi-Solid-State Electrochromic Cells with Energy Storage Properties Made with Inkjet Printing
Authors: Theodosiou Krystallia , Giannopoulos Panagiotis , Georgakopoulos Tilemachos , Stathatos Elias
Published: July 2020

In common commercially available electrochromic glass panes, the active materials such as WO3 and NiOx films are typically deposited by either physical vapor or sputtering under vacuum. In the present studies, we report on the inkjet printing method to deposit both electrochromic and ion storage electrode layers under ambient conditions. An ion storage layer based on cerium modified TiO2 and electrochromic nanocrystalline WO3 were both prepared under the wet method and deposited as inks on conductive substrates. Both compounds possess porous morphology facilitating high ion diffusion during electrochemical processes. In particular, the ion storage layer was evaluated in terms of porosity, charge capacity and ion diffusion coefficient. A scaled up 90 cm2 electrochromic device with quasi-solid-state electrolyte was made with the aforementioned materials and evaluated in terms of optical modulation in the visible region, cyclic voltammetry and color efficiency. High contrast between 13.2% and 71.6% for tinted and bleached states measured at 550 nm was monitored under low bias at +2.5 volt and −0.3 volts respectively. Moreover, the calculated energy density equal to 1.95 × 10−3 mWh cm−2 and the high areal capacitance of 156.19 mF cm−2 of the device could combine the electrochromic behavior of the cell with energy storage capability so as to be a promising candidate for future applications into smart buildings.
Oxidation Behavior of the Monolayered La2Zr2O7, Composite La2Zr2O7 + 8YSZ, and Double-Ceramic Layered La2Zr2O7/La2Zr2O7 + 8YSZ/8YSZ Thermal Barrier Coatings
Authors: Jasik Anna , Moskal Grzegorz , Mikuśkiewicz Marta , Tomaszewska Agnieszka , Jucha Sebastian , Migas Damian , Myalska Hanna
Published: July 2020

The degradation process of thermal barrier coatings (TBCs) such as monolayered La2Zr2O7, composite 50% La2Zr2O7 + 50% 8YSZ, and double-ceramic layer (DCL) La2Zr2O7/50% La2Zr2O7 + 50% 8YSZ/8YSZ was investigated. Coatings were deposited using the atmospheric plasma spraying (APS) process (ceramic layer and bond-coat) on the Ni-based superalloy substrate with Ni-22Cr-10Al-1Y bond-coat. The thickness of the ceramic top-coats in all cases were 300 µm. In the case of La2Zr2O7/8YSZ, the internal sublayer was built from 8YSZ powder whereas the outer from La2Zr2O7. Between both sublayers’ “composite” a 50% La2Zr2O7 + 50% 8YSZ zone was present. The “composite” 50% La2Zr2O7 + 50% 8YSZ TBC system was sprayed from two different feedstock powders with equal weight ratios. In the first part of the investigation, the microstructural characterization of the TBCs was presented. The main goals were related to the characterization of the degradation processes in different TBC systems with special emphasis on the phenomenon in the thermally grown oxide (TGO) zone related to oxidation, and the phenomenon related to phase stability in ceramic top-coats as related to temperature influence. The oxidation test was carried out in air at 1100 °C for 500 h. In the second step of the investigation, the numerical simulation of the monolayered TBC 8YSZ and La2Zr2O7 systems was analyzed from the stress distribution point of view. Additionally, the two-layered TBC coating of the DCL type was also analyzed.
Mechanism of Precipitate Microstructure Affecting Fatigue Behavior of 7020 Aluminum Alloy
Authors: Shan Zhaojun , Liu Shengdan , Ye Lingying , Li Yiran , He Chunhua , Chen Jin , Tang Jianguo , Deng Yunlai , Zhang Xinming
Published: July 2020

The effect of different precipitate microstructures obtained by different heat treatments on fatigue behavior of 7020 aluminum alloy was investigated. The fine Guinier Preston I (GPI) zones in the under-aged alloy can be repeatedly sheared by dislocations produced in cyclic loading, making the fatigue crack initiate difficultly and fatigue crack path propagate tortuously. Fatigue strength and fatigue crack propagation resistance of the alloy with shearable precipitates are much higher than those of the alloy with unshearable precipitates. The peak-aged alloy with continuous grain boundary precipitate (GBP) and narrow precipitate free zone (PFZ) is prone to initiate fatigue cracks and reduce fatigue strength. With the growth of unshearable precipitates, the fatigue strength of the alloy firstly increases and then decreases. Precipitates with moderate size in the over-aged alloy improve the roughness-induced crack closure (RICC) effect. Soft matrix with appropriate width between the precipitates can promote the slip reversibility and relax the crack tip stress. The fatigue strength of the moderately over-aged alloy reaches to 122.1 MPa at 107 cycles of loading, and the fatigue crack growth rate (FCGR) is 35.6% slower than that of the peak-aged alloy at ΔK of 10 MPa·m1/2.
Biaxial Testing Machine: Development and Evaluation
Authors: Pereira António B. , Fernandes Fábio A.O. , de Morais Alfredo B. , Maio João
Published: July 2020

Biaxial mechanical testing gained increased importance for characterization of materials that present anisotropic behavior and/or different responses when subjected to tensile and compression loadings. In this work, a new biaxial testing machine was developed. The various systems and components were designed, manufactured, assembled, and assessed. Uniaxial tensile tests were performed to validate the device, showing results consistent with those obtained on a universal testing machine. Finally, biaxial tensile tests were also performed on polypropylene cruciform specimens. The results revealed high precision levels, thus showing the potential of this new machine.
Can Citizens Affect the Performance of Their Elected Representatives? A Principal–Agent Model of Strategic Interaction in Democratic Systems
Authors: Lanza Giuseppe , Maimone Ansaldo Patti Dario , Navarra Pietro
Published: July 2020

According to standard economic theory, human beings are expected to work more and better when benefits in the form of lower costs or higher reward increase. Principal–agent theory applied to the theory of the firm relies on this relationship and states that employees should be paid according to how well they perform their tasks. In this framework, monitoring devices are introduced to control employees’ performance and determine salaries. In this paper we construct a principal–agent model to describe the relationship between citizens/voters and elected representatives in which monitoring devices are introduced to control the performance of the latter. We demonstrate that tighter controls may produce better performance but also may produce a reduction in the intrinsic motivations of elected representatives, resulting in a reduction of their work effort. These results are interpreted in the light of the motivation crowding theory.
The Global Well-Posedness for Large Amplitude Smooth Solutions for 3D Incompressible Navier–Stokes and Euler Equations Based on a Class of Variant Spherical Coordinates
Authors: Wang Shu , Wang Yongxin
Published: July 2020

This paper investigates the globally dynamical stabilizing effects of the geometry of the domain at which the flow locates and of the geometry structure of the solutions with the finite energy to the three-dimensional (3D) incompressible Navier–Stokes (NS) and Euler systems. The global well-posedness for large amplitude smooth solutions to the Cauchy problem for 3D incompressible NS and Euler equations based on a class of variant spherical coordinates is obtained, where smooth initial data is not axi-symmetric with respect to any coordinate axis in Cartesian coordinate system. Furthermore, we establish the existence, uniqueness and exponentially decay rate in time of the global strong solution to the initial boundary value problem for 3D incompressible NS equations for a class of the smooth large initial data and a class of the special bounded domain described by variant spherical coordinates.
Static and Dynamic Properties of a Few Spin 1/2 Interacting Fermions Trapped in a Harmonic Potential
Authors: Rojo-Francàs Abel , Polls Artur , Juliá-Díaz Bruno
Published: July 2020

We provide a detailed study of the properties of a few interacting spin 1 / 2 fermions trapped in a one-dimensional harmonic oscillator potential. The interaction is assumed to be well represented by a contact delta potential. Numerical results obtained by means of direct diagonalization techniques are combined with analytical expressions for both the non-interacting and strongly interacting regime. The N = 2 case is used to benchmark our numerical techniques with the known exact solution of the problem. After a detailed description of the numerical methods, in a tutorial-like manner, we present the static properties of the system for N = 2 , 3 , 4 and 5 particles, e.g., low-energy spectrum, one-body density matrix, ground-state densities. Then, we consider dynamical properties of the system exploring first the excitation of the breathing mode, using the dynamical structure function and corresponding sum-rules, and then a sudden quench of the interaction strength.
Optimal Feedback Control Problem for the Fractional Voigt-α Model
Authors: Zvyagin Victor , Zvyagin Andrey , Ustiuzhaninova Anastasiia
Published: July 2020

The study of the existence of an optimal feedback control problem for the initial-boundary value problem that describes the motion of the fractional Voigt- α model of a viscoelastic medium is investigated in this paper. In this model, the Voigt rheological relation is considered with the left-side fractional Riemann-Liouville derivative, which allows to take into account the memory of the medium. Also in this model, the memory is considered along the trajectory of the motion of fluid particles, determined by the velocity field. Due to the insufficient smoothness of the velocity field and, as a consequence, the impossibility of uniquely determining the trajectory for the velocity field for any initial value, a weak solution to the problem under study is introduced using regular Lagrangian flows. Based on the approximation-topological approach to the study of fluid dynamic problems, the existence of an optimal solution that gives a minimum to a given cost functional is proved.
Fourier Analysis with Generalized Integration
Authors: Arredondo Juan H. , Bernal Manuel , Morales María Guadalupe
Published: July 2020

We generalize the classic Fourier transform operator F p by using the Henstock–Kurzweil integral theory. It is shown that the operator equals the H K -Fourier transform on a dense subspace of L p , 1 < p ≤ 2 . In particular, a theoretical scope of this representation is raised to approximate the Fourier transform of functions on the mentioned subspace numerically. Besides, we show the differentiability of the Fourier transform function F p ( f ) under more general conditions than in Lebesgue’s theory. Additionally, continuity of the Fourier Sine transform operator into the space of Henstock-Kurzweil integrable functions is proved, which is similar in spirit to the already known result for the Fourier Cosine transform operator. Because our results establish a representation of the Fourier transform with more properties than in Lebesgue’s theory, these results might contribute to development of better algorithms of numerical integration, which are very important in applications.
Computer Analysis of Human Belligerency
Authors: A. Tenreiro Machado José , M. Lopes António , Mata Maria Eugénia
Published: July 2020

War is a cause of gains and losses. Economic historians have long stressed the extreme importance of considering the economic potential of society for belligerency, the role of management of chaos to bear the costs of battle and casualties, and ingenious and improvisation methodologies for emergency management. However, global and inter-temporal studies on warring are missing. The adoption of computational tools for data processing is a key modeling option with present day resources. In this paper, hierarchical clustering techniques and multidimensional scaling are used as efficient instruments for visualizing and describing military conflicts by electing different metrics to assess their characterizing features: time, time span, number of belligerents, and number of casualties. Moreover, entropy is adopted for measuring war complexity over time. Although wars have been an important topic of analysis in all ages, they have been ignored as a subject of nonlinear dynamics and complex system analysis. This paper seeks to fill these gaps in the literature by proposing a quantitative perspective based on algorithmic strategies. We verify the growing number of events and an explosion in their characteristics. The results have similarities to those exhibited by systems with increasing volatility, or evolving toward chaotic-like behavior. We can question also whether such dynamics follow the second law of thermodynamics since the adopted techniques reflect a system expanding the entropy.
Considering Random Factors in Modeling Complex Microeconomic Systems
Authors: Hoshovska Oksana , Poplavska Zhanna , Kryvinska Natalia , Horbal Natalia
Published: July 2020

Within the framework of a model describing real-functioning association of three enterprises, numerical calculations of economic dynamics parameters considering fluctuating market demand for the goods were performed. A methodology was suggested for approximated consideration of both seasonal and random demand fluctuations at the market of textile garments; the main steps of the suggested methodology were described. The main exogenous random factors within this model include, as stated above, the volume of market demand for the goods produced by the enterprises of the group. The basic volume of market demand is considered at the average actual level according to the results of the enterprises’ analysis, and additionally we take into account the influence of non-price factors, such as random changes in the consumers’ tastes, consumers’ income, and other random factors on the market demand. By volume of market demand, we consider the total amount of goods produced by the enterprises of the group that all consumers are willing and able to purchase at a specific price in a marketplace. The calculations were made based on actual values of external economic parameters, such as labor cost, product prices, etc. Influence of the market demand fluctuations on the companies’ activity has been illustrated both numerically and graphically, allowing the analysis of the impact of exogenous parameters on the companies output and profits. The suggested approach creates a basis for further analysis of the impact of random factors of a similar nature, i.e., stochastic shocks related to the level of interest rates, shifts and turnabouts in the social environment, as well as the market transformations due to annual/seasonal epidemics.
Viral Infection Dynamics Model Based on a Markov Process with Time Delay between Cell Infection and Progeny Production
Authors: Sazonov Igor , Grebennikov Dmitry , Kelbert Mark , Meyerhans Andreas , Bocharov Gennady
Published: July 2020

Many human virus infections including those with the human immunodeficiency virus type 1 (HIV) are initiated by low numbers of founder viruses. Therefore, random effects have a strong influence on the initial infection dynamics, e.g., extinction versus spread. In this study, we considered the simplest (so-called, ‘consensus’) virus dynamics model and incorporated a delay between infection of a cell and virus progeny release from the infected cell. We then developed an equivalent stochastic virus dynamics model that accounts for this delay in the description of the random interactions between the model components. The new model is used to study the statistical characteristics of virus and target cell populations. It predicts the probability of infection spread as a function of the number of transmitted viruses. A hybrid algorithm is suggested to compute efficiently the system dynamics in state space domain characterized by the mix of small and large species densities.
The Impact of Novel Anticoagulants on the Upper Gastrointestinal Tract Mucosa
Authors: Mihalkanin Lubomir , Stancak Branislav
Published: July 2020

Background and objectives: Although treatment with novel oral non-vitamin K antagonist 3anticoagulants (NOACs) is associated with an overall decrease in hemorrhagic complications compared to warfarin, the incidence of gastrointestinal bleeding remains contradictory. Materials and Methods: After the exclusion of patients with pre-existing pathological lesions in the upper gastrointestinal tract (GIT) on esophageal-gastroduodenoscopy (EGD) at entry, a cohort of 80 patients (mean age of 74.8 ± 2.0 years) was randomly divided into four equivalent groups, treated with dabigatran, rivaroxaban, apixaban, or warfarin. Patients were prospectively followed up for three months of treatment, with a focus on anamnestic and endoscopic signs of bleeding. In addition, bleeding risk factors were evaluated. Results: In none of the patients treated with warfarin or NOACs was any serious or clinically significant bleeding recorded within the follow-up period. The incidence of clinical bleeding and endoscopically detected bleeding in the upper GT after three months of treatment was not statistically different among groups (χ2 = 2.8458; p = 0.41608). The presence of Helicobacter pylori (HP) was a risk factor for upper GIT bleeding (p < 0.05), while the use of proton pump inhibitors (PPIs) was a protective factor (p = 0.206; Spearman’s correlation coefficient = 0.205). We did not record any post-biopsy continued bleeding. Conclusions: No significant GIT bleeding was found in any of the treatment groups, so we consider it beneficial to perform routine EGD before the initiation of any anticoagulant therapy in patients with an increased risk of upper GIT bleeding. Detection and eradication of HP as well as preventive PPI treatment may mitigate the occurrence of endoscopic bleeding. Endoscopic biopsy during the NOAC treatment is safe.
Spontaneous Heterotopic Pregnancy: Case Report and Literature Review
Authors: Černiauskaitė Miglė , Vaigauskaitė Brigita , Ramašauskaitė Diana , Šilkūnas Mindaugas
Published: July 2020

Heterotopic pregnancy is defined as a condition when intrauterine and extrauterine pregnancy occur simultaneously. It is a life-threatening condition that requires immediate and accurate diagnostics and treatment. We present a case of a 28-year-old primigravida female who conceived spontaneously and at her seventh week of gestation and was presented to the emergency department with weakness and acute pain in lower abdomen. Laboratory tests and transvaginal ultrasonography revealed the diagnosis of heterotopic pregnancy. Urgent laparoscopic salpingotomy was chosen as a treatment option. The ectopic pregnancy was successfully removed with the preservation of the intrauterine embryo and fallopian tubes. The course of pregnancy after the surgery was without complications, and a healthy baby was delivered at the 39th week of gestation. When treated properly and on time, a heterotopic pregnancy can result in live childbirth with favorable outcomes for both the child and the mother.
Surface Modifications of Anion Exchange Membranes for an Improved Reverse Electrodialysis Process Performance: A Review
Authors: Kotoka Francis , Merino-Garcia Ivan , Velizarov Svetlozar
Published: July 2020

Reverse electrodialysis (RED) technology represents a promising electro-membrane process for renewable energy harvesting from aqueous streams with different salinity. However, the performance of the key components of the system, that is, the ion exchange membranes, is limited by both the presence of multivalent ions and fouling phenomena, thus leading to a reduced generated net power density. In this context, the behavior of anion exchange membranes (AEMs) in RED systems is more severely affected, due to the undesirable interactions between their positively charged fixed groups and, mostly negatively charged, foulant materials present in natural streams. Therefore, controlling both the monovalent anion permselectivity and the membrane surface hydrophilicity is crucial. In this respect, different surface modification procedures were considered in the literature, to enhance the above-mentioned properties. This review reports and discusses the currently available approaches for surface modifications of AEMs, such as graft polymerization, dip coating, and layer-by-layer, among others, mainly focusing on preparing monovalent permselective AEMs with antifouling characteristics, but also considering hydrophilicity aspects and identifying the most promising modifying agents to be utilized. Thus, the present study aimed at providing new insights for the further design and development of selective, durable, and cost-effective modified AEMs for an enhanced RED process performance, which is indispensable for a practical implementation of this electro-membrane technology at an industrial scale.
Viscosity of BOF Slag
Authors: Kovtun Oleksandr , Korobeinikov Iurii , C Srishilan , Shukla Ajay Kumar , Volkova Olena
Published: July 2020

The viscosities of the industrial basic oxygen furnace (BOF) slag with varying compositions of MgO, Al2O3, TiO2, and MnO were continuously measured at a temperature range between 1400 and 1700 °C using the rotating bob method. Three characteristic temperatures for the melting behavior of the BOF slag were investigated using a high-temperature microscope. The solid fraction of the slag was calculated by FactSage 7.2 using the FTOxid database. General observations from the experimental data show that the increase in MgO tends to increase viscosity. However, Al2O3, TiO2, and MnO decrease viscosity up to a certain level, and beyond that, they also increase the viscosity. The measured values of the viscosity of BOF slags were compared and discussed with known data from the literature. Finally, the activation energy of BOF slags with different compositions of MgO, Al2O3, TiO2, and MnO was calculated in the temperature range of industrial operations.
Experimental Study on the Dissolution Behavior of Calcium Fluoride
Authors: Sar Suchandra , Samuelsson Caisa , Engström Fredrik , Ökvist Lena Sundqvist
Published: July 2020

The presence of halogens has an adverse effect on the zinc extraction process through electrowinning, the last phase of the RLE (Roasting, Leaching and Electrowinning) zinc extraction route. Fluoride (F−) may be present as calcium fluoride (CaF2) and this is, for example, the case in double leached Waelz oxide (DLWO). Efficient removal of F− from primary and secondary raw materials for zinc extraction results in a simplified process and increases flexibility in the selection of raw materials. Understanding of the solubility behavior of pure CaF2 can give valuable information on treatment for maximized halogen removal. Dissolution of CaF2 was studied with the addition of sodium carbonate (Na2CO3) and sodium bicarbonate (NaHCO3). Dissolution studies were combined with thermodynamic calculations to understand the solubility behavior of CaF2 under different conditions. Results from the experiments and the thermodynamic calculations show that Na2CO3 and NaHCO3 have similar behavior if the pH is controlled at the same value. The available carbonate (CO32−) ion in the system limits the concentration of calcium (Ca2+) ion by precipitation of CaCO3, which enhances the dissolution of CaF2. At higher temperatures and pH, calcite, vaterite, and aragonite were formed and co-precipitation of CaF2 along with calcium carbonate (CaCO3) was observed. At lower temperatures and lower pH levels, only calcite and vaterite were formed and a coating by CaCO3 on CaF2 was found to hinder complete dissolution reaction. The results of this study indicate that the temperature along with the reagents used for the dissolution tests have a significant impact on the CaCO3 polymorph mixture (calcite, vaterite and aragonite) formation.
Metabolic Reprogramming of Chemoresistant Cancer Cells and the Potential Significance of Metabolic Regulation in the Reversal of Cancer Chemoresistance
Authors: Chen Xun , Chen Shangwu , Yu Dongsheng
Published: July 2020

Metabolic reprogramming is one of the hallmarks of tumors. Alterations of cellular metabolism not only contribute to tumor development, but also mediate the resistance of tumor cells to antitumor drugs. The metabolic response of tumor cells to various chemotherapy drugs can be analyzed by metabolomics. Although cancer cells have experienced metabolic reprogramming, the metabolism of drug resistant cancer cells has been further modified. Metabolic adaptations of drug resistant cells to chemotherapeutics involve redox, lipid metabolism, bioenergetics, glycolysis, polyamine synthesis and so on. The proposed metabolic mechanisms of drug resistance include the increase of glucose and glutamine demand, active pathways of glutaminolysis and glycolysis, promotion of NADPH from the pentose phosphate pathway, adaptive mitochondrial reprogramming, activation of fatty acid oxidation, and up-regulation of ornithine decarboxylase for polyamine production. Several genes are associated with metabolic reprogramming and drug resistance. Intervening regulatory points described above or targeting key genes in several important metabolic pathways may restore cell sensitivity to chemotherapy. This paper reviews the metabolic changes of tumor cells during the development of chemoresistance and discusses the potential of reversing chemoresistance by metabolic regulation.
Optimized Protocol for the In Situ Derivatization of Glutathione with N-Ethylmaleimide in Cultured Cells and the Simultaneous Determination of Glutathione/Glutathione Disulfide Ratio by HPLC-UV-QTOF-MS
Authors: Sun Xueni , Berger Raffaela S. , Heinrich Paul , Marchiq Ibtissam , Pouyssegur Jacques , Renner Kathrin , Oefner Peter J. , Dettmer Katja
Published: July 2020

Glutathione (GSH) and glutathione disulfide (GSSG) are commonly used to assess the oxidative status of a biological system. Various protocols are available for the analysis of GSH and GSSG in biomedical specimens. In this study, we present an optimized protocol for the in situ derivatization of GSH with N-ethylmaleimide (NEM) to prevent GSH autooxidation, and thus to preserve the GSH/GSSG ratio during sample preparation. The protocol comprises the incubation of cells in NEM containing phosphate buffered saline (PBS), followed by metabolite extraction with 80% methanol. Further, to preserve the use of QTOF-MS, which may lack the linear dynamic range required for the simultaneous quantification of GSH and GSSG in non-targeted metabolomics, we combined liquid chromatographic separation with the online monitoring of UV absorbance of GS-NEM at 210 nm and the detection of GSSG and its corresponding stable isotope-labeled internal standard by QTOF-MS operated with a 10 Da Q1 window. The limit of detection (LOD) for GS-NEM was 7.81 µM and the linear range extended from 15.63 µM to 1000 µM with a squared correlation coefficient R2 of 0.9997. The LOD for GSSG was 0.001 µM, and the lower limit of quantification (LLOQ) was 0.01 µM, with the linear (R2 = 0.9994) range extending up to 10 µM. The method showed high repeatability with intra-run and inter-run coefficients of variation of 3.48% and 2.51% for GS-NEM, and 3.11% and 3.66% for GSSG, respectively. Mean recoveries of three different spike-in levels (low, medium, high) of GSSG and GS-NEM were above 92%. Finally, the method was applied to the determination of changes in the GSH/GSSG ratio either in response to oxidative stress in cells lacking one or both monocarboxylate transporters MCT1 and MCT4, or in adaptation to the NADPH (nicotinamide adenine dinucleotide phosphate) consuming production of D-2-hydroxyglutarate in cells carrying mutations in the isocitrate dehydrogenase genes IDH1 and IDH2.
An NMR Metabolomics Approach to Investigate Factors Affecting the Yoghurt Fermentation Process and Quality
Authors: Trimigno Alessia , Bøge Lyndgaard Christian , Atladóttir Guðrún Anna , Aru Violetta , Balling Engelsen Søren , Harder Clemmensen Line Katrine
Published: July 2020

A great number of factors can influence milk fermentation for yoghurt production such as fermentation conditions, starter cultures and milk characteristics. It is important for dairy companies to know the best combinations of these parameters for a controlled fermentation and for the desired qualities of yoghurt. This study investigates the use of a 1H-NMR metabolomics approach to monitor the changes in milk during fermentation from time 0 to 24 h, taking samples every hour in the first 8 h and then at the end-point at 24 h. Three different starter cultures (L. delbrueckii ssp. bulgaricus, S. thermophilus and their combination) were used and two different heat treatments (99 or 105 °C) were applied to milk. The results clearly show the breakdown of proteins and lactose as well as the concomitant increase in acetate, lactate and citrate during fermentation. Formate is found at different initial concentrations depending on the heat treatment of the milk and its different time trajectory depends on the starter cultures: Lactobacillus cannot produce formate, but needs it for growth, whilst Streptococcus is able to produce formate from pyruvate, therefore promoting the symbiotic relationship between the two strains. On the other hand, Lactobacillus can hydrolyze milk proteins into amino acids, enriching the quality of the final product. In this way, better insight into the protocooperation of lactic acid bacteria strains and information on the impact of a greater heat treatment in the initial matrix were obtained. The global chemical view on the fermentations provided using NMR is key information for yoghurt producers and companies producing starter cultures.
Application of Multiblock Analysis on Small Metabolomic Multi-Tissue Dataset
Authors: Torell Frida , Skotare Tomas , Trygg Johan
Published: July 2020

Data integration has been proven to provide valuable information. The information extracted using data integration in the form of multiblock analysis can pinpoint both common and unique trends in the different blocks. When working with small multiblock datasets the number of possible integration methods is drastically reduced. To investigate the application of multiblock analysis in cases where one has a few number of samples and a lack of statistical power, we studied a small metabolomic multiblock dataset containing six blocks (i.e., tissue types), only including common metabolites. We used a single model multiblock analysis method called the joint and unique multiblock analysis (JUMBA) and compared it to a commonly used method, concatenated principal component analysis (PCA). These methods were used to detect trends in the dataset and identify underlying factors responsible for metabolic variations. Using JUMBA, we were able to interpret the extracted components and link them to relevant biological properties. JUMBA shows how the observations are related to one another, the stability of these relationships, and to what extent each of the blocks contribute to the components. These results indicate that multiblock methods can be useful even with a small number of samples.
Correction: Lukša, J., et al. Fungal Microbiota of Sea Buckthorn Berries at Two Ripening Stages and Volatile Profiling of Potential Biocontrol Yeasts. Microorganisms 2020, 8, 456
Authors: Lukša Juliana , Vepštaitė-Monstavičė Iglė , Apšegaitė Violeta , Blažytė-Čereškienė Laima , Stanevičienė Ramunė , Strazdaitė-Žielienė Živilė , Ravoitytė Bazilė , Aleknavičius Dominykas , Būda Vincas , Mozūraitis Raimondas , Servienė Elena
Published: July 2020

The authors wish to make the following corrections to this paper [...]
Effects of Plasma-Activated Water on Skin Wound Healing in Mice
Authors: Xu Dehui , Wang Shuai , Li Bing , Qi Miao , Feng Rui , Li Qiaosong , Zhang Hao , Chen Hailan , Kong Michael G
Published: July 2020

Cold atmospheric plasma (CAP) has been widely used in biomedicine during the last two decades. While direct plasma treatment has been reported to promote wound healing, its application can be uneven and inconvenient. In this study, we first activated water with a portable dielectric barrier discharge plasma device and evaluated the inactivation effect of plasma-activated water (PAW) on several kinds of bacteria that commonly infect wounds. The results show that PAW can effectively inactivate these bacteria. Then, we activated tap water and examined the efficacy of PAW on wound healing in a mouse model of full-thickness skin wounds. We found that wound healing in mice treated with PAW was significantly faster compared with the control group. Histological analysis of the skin tissue of mice wounds showed a significant reduction in the number of inflammatory cells in the PAW treatment group. To identify the possible mechanism by which PAW promotes wound healing, we analyzed changes in the profiles of wound bacteria after PAW treatment. The results show that PAW can significantly reduce the abundance of wound bacteria in the treatment group. The results of biochemical blood tests and histological analysis of major internal organs in the mice show that PAW had no obvious side effects. Taken together, these results indicate that PAW may be a new and effective method for promoting wound healing without side effects.
Skin Bacteria Mediate Glycerol Fermentation to Produce Electricity and Resist UV-B
Authors: Balasubramaniam Arun , Adi Prakoso , Do Thi Tra My , Yang Jen-Ho , Labibah Asy Syifa , Huang Chun-Ming
Published: July 2020

Bacteria that use electron transport proteins in the membrane to produce electricity in the gut microbiome have been identified recently. However, the identification of electrogenic bacteria in the skin microbiome is almost completely unexplored. Using a ferric iron-based ferrozine assay, we have identified the skin Staphylococcus epidermidis (S. epidermidis) as an electrogenic bacterial strain. Glycerol fermentation was essential for the electricity production of S. epidermidis since the inhibition of fermentation by 5-methyl furfural (5-MF) significantly diminished the bacterial electricity measured by voltage changes in a microbial fuel cell (MFC). A small-scale chamber with both anode and cathode was fabricated in order to study the effect of ultraviolet-B (UV-B) on electricity production and bacterial resistance to UV-B. Although UV-B lowered bacterial electricity, a prolonged incubation of S. epidermidis in the presence of glycerol promoted fermentation and elicited higher electricity to suppress the effect of UV-B. Furthermore, the addition of glycerol into S. epidermidis enhanced bacterial resistance to UV-B. Electricity produced by human skin commensal bacteria may be used as a dynamic biomarker to reflect the UV radiation in real-time.