bluuebunny/crossref_metadata_2025 huggingface dataset:
One-Step Synthesis of b-N-TiO2/C Nanocomposites with High Visible Light Photocatalytic Activity to Degrade Microcystis aeruginosa
Authors: Zhang Xu , Cai Min , Cui Naxin , Chen Guifa , Zou Guoyan , Zhou Li
Published: May 2020

Black TiO2 with doped nitrogen and modified carbon (b-N-TiO2/C) were successfully prepared by sol-gel method in the presence of urea as a source of nitrogen and carbon. The photocatalysts were characterized by field emission scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman, electron paramagnetic resonance (EPR), and UV-vis diffuse reflectance spectra (DRS). The doped nitrogen, introduced defects, and modified carbon played a synergistic role in enhancing photocatalytic activity of b-N-TiO2/C for the degradation of chlorophyll-a in algae cells. The sample, with a proper amount of phase composition and oxygen vacancies, showed the highest efficiency to degrade chlorophyll-a, and the addition of H2O2 promoted this photocatalysis degradation. Based on the trapping experiments and electron spin resonance (ESR) signals, a photocatalytic mechanism of b-N-TiO2/C was proposed. In the photocatalytic degradation of chlorophyll-a, the major reactive species were identified as OH and O2−. This research may provide new insights into the photocatalytic inactivation of algae cells by composite photocatalysts.
Evidence for Overlapping and Distinct Biological Activities and Transcriptional Targets Triggered by Fibroblast Growth Factor Receptor 2b Signaling between Mid- and Early Pseudoglandular Stages of Mouse Lung Development
Authors: Jones Matthew R. , Lingampally Arun , Wu Jin , Sedighi Jamschid , Ahmadvand Negah , Wilhelm Jochen , Vazquez-Armendariz Ana Ivonne , Herold Susanne , Chen Chengshui , Zhang Jin-San , Bellusci Saverio , Chao Cho-Ming
Published: May 2020

Branching morphogenesis is the basic developmental mode common to organs such as the lungs that undergo a process of ramification from a rudimentary tree. However, the precise molecular and cellular bases underlying the formation of branching organs are still unclear. As inactivation of fibroblast growth factor receptor 2b (Fgfr2b) signaling during early development leads to lung agenesis, thereby preventing the analysis of this pathway at later developmental stages, we used transgenic mice to induce expression of a soluble form of Fgfr2b to inactivate Fgfr2b ligands at embryonic day (E) 14.5, corresponding to the mid-pseudoglandular stage of lung development. We identified an Fgfr2b signaling signature comprised of 46 genes enriched in the epithelium, some of which were common to, but most of them distinct from, the previously identified Fgfr2b signaling signature at E12.5. Our results indicate that Fgfr2b signaling at E14.5 controls mostly proliferation and alveolar type 2 cell (AT2) differentiation. In addition, inhibition of Fgfr2b signaling at E14.5 leads to morphological and cellular impairment at E18.5, with defective alveolar lineage formation. Further studies will have to be conducted to elucidate the role of Fgfr2b signaling at successive stages (canalicular/saccular/alveolar) of lung development as well as during homeostasis and regeneration and repair after injury.
Silibinin Upregulates CXCR4 Expression in Cultured Bone Marrow Cells (BMCs) Especially in Pulmonary Arterial Hypertension Rat Model
Authors: Zhang Tingting , Kawaguchi Nanako , Tsuji Kunikazu , Hayama Emiko , Furutani Yoshiyuki , Sugiyama Hisashi , Nakanishi Toshio
Published: May 2020

Previously we reported that silibinin ameliorated pulmonary arterial hypertension (PAH) in rat PAH models, possibly through the suppression of the CXCR4/SDF-1, until the point where PAH became a severe and irreversible condition. To further investigate how silibinin ameliorates PAH, we first attempted to clarify its effect on bone marrow cells (BMCs), since the CXCR4/SDF-1 axis is known to regulate stem cell migration and attachment in BM niches. Rat PAH models were established through a combination of a single subcutaneous injection of monocrotaline (MCT) and chronic hypoxic conditions (10% O2). BMCs were harvested and cultured, and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and flow cytometry (FCM) were performed to investigate whether silibinin affected CXCR4 expression. Silibinin upregulated the gene expression of stem cell related markers CXCR4, SDF-1, SCF, and c-Kit, inflammatory markers IL-6 and TNFα, mesenchymal stem cell (MSC)-related markers CD44 and CD29, and the granulocyte/monocyte-macrophage marker CD14 in cultured BM in PAH rats, but not in normal rats, except CXCR4. FCM showed that silibinin increased the CXCR4-positive cell population in a granulocyte fraction of cultured BMCs. However, immunohistochemical (IHC) staining showed no significant change in CXCR4 expression in the BM of the tibias. These results suggest that silibinin increases the expression of CXCR4 in BM, and the increased CXCR4-positive cells could be granulocytes/monocyte-macrophages.
Evaluation of a Novel Boron-Containing α-d-Mannopyranoside for BNCT
Authors: Tsurubuchi Takao , Shirakawa Makoto , Kurosawa Wataru , Matsumoto Kayo , Ubagai Risa , Umishio Hiroshi , Suga Yasuyo , Yamazaki Junko , Arakawa Akihiro , Maruyama Yutaka , Seki Takuya , Shibui Yusuke , Yoshida Fumiyo , Zaboronok Alexander , Suzuki Minoru , Sakurai Yoshinori , Tanaka Hiroki , Nakai Kei , Ishikawa Eiichi , Matsumura Akira
Published: May 2020

Boron neutron capture therapy (BNCT) is a unique anticancer technology that has demonstrated its efficacy in numerous phase I/II clinical trials with boronophenylalanine (BPA) and sodium borocaptate (BSH) used as 10B delivery agents. However, continuous drug administration at high concentrations is needed to maintain sufficient 10B concentration within tumors. To address the issue of 10B accumulation and retention in tumor tissue, we developed MMT1242, a novel boron-containing α-d-mannopyranoside. We evaluated the uptake, intracellular distribution, and retention of MMT1242 in cultured cells and analyzed biodistribution, tumor-to-normal tissue ratio and toxicity in vivo. Fluorescence imaging using nitrobenzoxadiazole (NBD)-labeled MMT1242 and inductively coupled mass spectrometry (ICP-MS) were performed. The effectiveness of BNCT using MMT1242 was assessed in animal irradiation studies at the Kyoto University Research Reactor. MMT1242 showed a high uptake and broad intracellular distribution in vitro, longer tumor retention compared to BSH and BPA, and adequate tumor-to-normal tissue accumulation ratio and low toxicity in vivo. A neutron irradiation study with MMT1242 in a subcutaneous murine tumor model revealed a significant tumor inhibiting effect if injected 24 h before irradiation. We therefore report that 10B-MMT1242 is a candidate for further clinical BNCT studies.
YRNAs: New Insights and Potential Novel Approach in Head and Neck Squamous Cell Carcinoma
Authors: Guglas Kacper , Kolenda Tomasz , Stasiak Maciej , Kopczyńska Magda , Teresiak Anna , Ibbs Matthew , Bliźniak Renata , Lamperska Katarzyna
Published: May 2020

YRNAs are a class of non-coding RNAs that are components of the Ro60 ribonucleoprotein particle and are essential for initiation of DNA replication. Ro60 ribonucleoprotein particle is a target of autoimmune antibodies in patients suffering from systemic lupus erythematosus and Sjögren’s syndrome. Deregulation of YRNAs has been confirmed in many cancer types, but not in head and neck squamous cell carcinoma (HNSCC). The main aim of this study was to determine the biological role of YRNAs in HNSCC, the expression of YRNAs, and their usefulness as potential HNSCC biomarkers. Using quantitative reverse transcriptase (qRT)-PCR, the expression of YRNAs was measured in HNSCC cell lines, 20 matched cancer tissues, and 70 FFPETs (Formaline-Fixed Paraffin-Embedded Tissue) from HNSCC patients. Using TCGA (The Cancer Genome Atlas) data, an analysis of the expression levels of selected genes, and clinical-pathological parameters was performed. The expression of low and high YRNA1 expressed groups were analysed using gene set enrichment analysis (GSEA). YRNA1 and YRNA5 are significantly downregulated in HNSCC cell lines. YRNA1 was found to be significantly downregulated in patients’ tumour sample. YRNAs were significantly upregulated in T4 stage. YRNA1 showed the highest sensitivity, allowing to distinguish healthy from cancer tissue. An analysis of TCGA data revealed that expression of YRNA1 was significantly altered in the human papilloma virus (HPV) infection status. Patients with medium or high expression of YRNA1 showed better survival outcomes. It was noted that genes correlated with YRNA1 were associated with various processes occurring during cancerogenesis. The GSEA analysis showed high expression enrichment in eight vital processes for cancer development. YRNA1 influence patients’ survival and could be used as an HNSCC biomarker. YRNA1 seems to be a good potential biomarker for HNSCC, however, more studies must be performed and these observations should be verified using an in vitro model.
Low-Temperature Pyrolysis of Municipal Solid Waste Components and Refuse-Derived Fuel—Process Efficiency and Fuel Properties of Carbonized Solid Fuel
Authors: Świechowski Kacper , Syguła Ewa , Koziel Jacek A. , Stępień Paweł , Kugler Szymon , Manczarski Piotr , Białowiec Andrzej
Published: May 2020

New technologies to valorize refuse-derived fuels (RDFs) will be required in the near future due to emerging trends of (1) the cement industry’s demands for high-quality alternative fuels and (2) the decreasing calorific value of the fuels derived from municipal solid waste (MSW) and currently used in cement/incineration plants. Low-temperature pyrolysis can increase the calorific value of processed material, leading to the production of value-added carbonized solid fuel (CSF). This dataset summarizes the key properties of MSW-derived CSF. Pyrolysis experiments were completed using eight types of organic waste and their two RDF mixtures. Organic waste represented common morphological groups of MSW, i.e., cartons, fabrics, kitchen waste, paper, plastic, rubber, PAP/AL/PE composite packaging (multi-material packaging also known as Tetra Pak cartons), and wood. The pyrolysis was conducted at temperatures ranging from 300 to 500 °C (20 °C intervals), with a retention (process) time of 20 to 60 min (20 min intervals). The mass yield, energy densification ratio, and energy yield were determined to characterize the pyrolysis process efficiency. The raw materials and produced CSF were tested with proximate analyses (moisture content, organic matter content, ash content, and combustible part content) and with ultimate analyses (elemental composition C, H, N, S) and high heating value (HHV). Additionally, differential scanning calorimetry (DSC) and thermogravimetric analyses (TGA) of the pyrolysis process were performed. The dataset documents the changes in fuel properties of RDF resulting from low-temperature pyrolysis as a function of the pyrolysis conditions and feedstock type. The greatest HHV improvements were observed for fabrics (up to 65%), PAP/AL/PE composite packaging (up to 56%), and wood (up to 46%).
Subjective Versus Quantitative Methods of Assessing Breast Density
Authors: Alomaim Wijdan , O’Leary Desiree , Ryan John , Rainford Louise , Evanoff Michael , Foley Shane
Published: May 2020

In order to find a consistent, simple and time-efficient method of assessing mammographic breast density (MBD), different methods of assessing density comparing subjective, quantitative, semi-subjective and semi-quantitative methods were investigated. Subjective MBD of anonymized mammographic cases (n = 250) from a national breast-screening programme was rated by 49 radiologists from two countries (UK and USA) who were voluntarily recruited. Quantitatively, three measurement methods, namely VOLPARA, Hand Delineation (HD) and ImageJ (IJ) were used to calculate breast density using the same set of cases, however, for VOLPARA only mammographic cases (n = 122) with full raw digital data were included. The agreement level between methods was analysed using weighted kappa test. Agreement between UK and USA radiologists and VOLPARA varied from moderate (κw = 0.589) to substantial (κw = 0.639), respectively. The levels of agreement between USA, UK radiologists, VOLPARA with IJ were substantial (κw = 0.752, 0.768, 0.603), and with HD the levels of agreement varied from moderate to substantial (κw = 0.632, 0.680, 0.597), respectively. This study found that there is variability between subjective and objective MBD assessment methods, internationally. These results will add to the evidence base, emphasising the need for consistent, simple and time-efficient MBD assessment methods. Additionally, the quickest method to assess density is the subjective assessment, followed by VOLPARA, which is compatible with a busy clinical setting. Moreover, the use of a more limited two-scale system improves agreement levels and could help minimise any potential country bias.
Diagnosis of Parkinson’s Disease by A Metabolomics-Based Laboratory-Developed Test (LDT)
Authors: Lokhov Petr G. , Trifonova Oxana P. , Maslov Dmitry L. , Lichtenberg Steven , Balashova Elena E.
Published: May 2020

A laboratory-developed test (LDT) is a type of in vitro diagnostic test that is designed, manufactured and used in the same laboratory (i.e., an in-house test). In this study, a metabolomics-based LDT was developed. This test involves a blood plasma preparation, direct-infusion mass spectrometry analysis with a high-resolution mass spectrometer, alignment and normalization of mass peaks using original algorithms, metabolite annotation by a biochemical context-driven algorithm, detection of overrepresented metabolic pathways and results in a visualization in the form of a pathway names cloud. The LDT was applied to detect early stage Parkinson’s disease (PD)—the diagnosis of which currently requires great effort due to the lack of available laboratory tests. In a case–control study (n = 56), the LDT revealed a statistically sound pattern in the PD-relevant pathways. Usage of the LDT for individuals confirmed its ability to reveal this pattern and thus diagnose PD at the early-stage (1–2.5 stages, according to Hoehn and Yahr scale). The detection of this pattern by LDT could diagnose PD with a specificity of 64%, sensitivity of 86% and an accuracy of 75%. Thus, this LDT can be used for further widespread testing.
Optimization of the CDC Protocol of Molecular Diagnosis of COVID-19 for Timely Diagnosis
Authors: Chen Chao-Ju , Hsieh Li-Ling , Lin Shu-Kai , Wang Chu-Feng , Huang Yi-Hui , Lin Shang-Yi , Lu Po-Liang
Published: May 2020

Coronavirus disease 2019 (COVID-19), the current uncontrolled outbreak of infectious disease, has caused significant challenges throughout the world. A reliable rapid diagnostic test for COVID-19 is demanded worldwide. The real-time reverse transcriptase polymerase chain was one of the most quickly established methods in the novel viral pandemic and was considered as the gold standard for the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this report, we illustrate our experience of applying a protocol from the Taiwan CDC and achieving assay optimization in the immediate circumstances to meet the urgent medical and public health needs.
The Response of US Macroeconomic Aggregates to Price Shocks in Crude Oil vs. Natural Gas
Authors: Shang Jin , Hamori Shigeyuki
Published: May 2020

Price fluctuations in crude oil and natural gas, as important sources of energy, have a remarkable influence on our economies and daily lives. Therefore, it is extremely important to react appropriately and to formulate appropriate policies or strategies to reduce the expected negative effects of fluctuations. However, as Kilian suggested, not all oil price shocks are similar; price increases can have diverse impacts on the real price of oil, depending on the underlying determinants of the price fluctuation. Therefore, economists, policymakers, and investors need to decompose real price shocks and evaluate the responses of macroeconomic aggregates to different types of shocks. In this study, we investigate and compare the different effects crude oil and natural gas price shocks have on US real GDP and CPI levels, utilizing a two-stage method based on a structural vector autoregression (SVAR) model proposed by Kilian. We found that a crude oil specific demand shock made larger contributions to the real price of oil than a natural gas specific demand shock did to the real price of gas, and that specific demand shocks in crude oil and natural gas markets had different effects on US CPI inflation and had similar effects on the real US GDP level.
Ground Fault Detection Using Hybrid Method in IT System LVDC Microgrid
Authors: Lee Kyung-Min , Park Chul-Won
Published: May 2020

Low voltage direct current (LVDC) microgrid systems have many advantages over low voltage alternating current (LVAC) systems. Furthermore, LVDC microgrids are growing in use because they are easy to link to distributed energy resources (DER) and energy storage systems (ESS), etc. Currently, IT system LVDC microgrids are widely used in direct current (DC) railways, hospitals, photovoltaic (PV) systems, and so on. When a ground fault occurs in an IT system LVDC microgrid, the ground fault may not be detected because the fault current is very small and there is no current path. In this paper, ground fault detection is proposed using a hybrid method that comprises pulsation signal generator injection and detailed coefficients of discrete wavelet transform (DWT). The LVDC microgrid was modeled and simulated using power systems computer-aided design (PSCAD). In addition, the proposed hybrid method was implemented using MATLAB’s wave menu, a script m-file, and the PSCAD library. The proper threshold was selected and tested by fault resistance change and load variation. In order to verify the superiority of the proposed hybrid method, a comparative study with the conventional method was performed. The results of various simulations show that the proposed hybrid detection method has normal operation and accurately and rapidly detects ground faults.
Electrical Damping Assessment and Stability Considerations for a Highly Electrified Liquefied Natural Gas Plant
Authors: Bongini Lorenzo , Mastromauro Rosa Anna , Sgrò Daniele , Malvaldi Fabrizio
Published: May 2020

In recent years, the Oil & Gas industry has been subjected to a progressive electrification process aiming to comply with global environmental requirements on CO2 emissions reduction. High-power electric motors fed by Variable Frequency Drives (VFDs) have replaced gas turbines as drivers for gas compression applications. In Liquefied Natural Gas (LNG) plants, unexpected downturns could be experienced in case of high torsional vibrations of power generations units. These torsional vibrations derive from the interaction among turbine-generator (TG) units and VFDs and are known as Sub-Synchronous Torsional Interactions (SSTIs). SSTIs can lead to instability when the overall electromechanical system lacks sufficient damping. In this scenario, electrical damping assessment is fundamental in order to ensure stability and reliable operation of an LNG plant. Negative electrical damping is strictly related to the negative incremental resistance behavior of the power converters and it is influenced by the converter’s control system. In this paper, a real case study based on Thyristor Variable Frequency Drives (TVFDs) is considered. Ad hoc dynamic models of the power converters and of the TG unit are developed and combined in order to provide an accurate estimation of the electrical damping. It is demonstrated that the electrical damping is affected by variations of the main control system parameters and how the use of a simplified model instead of an ad hoc model can impact the stability evaluation.
A Dynamic Multi-Swarm Particle Swarm Optimizer for Multi-Objective Optimization of Machining Operations Considering Efficiency and Energy Consumption
Authors: Song Lijun , Shi Jing , Pan Anda , Yang Jie , Xie Jun
Published: May 2020

Facing energy shortage and severe environmental pollution, manufacturing companies need to urgently energy consumption, make rational use of resources and improve economic benefits. This paper formulates a multi-objective optimization model for lathe turning operations which aims to simultaneously minimize energy consumption, machining cost and cutting time. A dynamic multi-swarm particle swarm optimizer (DMS-PSO) is proposed to solve the formulation. A case study is provided to illustrate the effectiveness of the proposed algorithm. The results show that the DMS-PSO approach can ensure good convergence and diversity of the solution set. Additionally, the optimal machining parameters are identified by fuzzy comprehensive evaluation (FCE) and compared with empirical parameters. It is discovered that the optimal parameters obtained from the proposed algorithm outperform the empirical parameters in all three objectives. The research findings shed new light on energy conservation of machining operations.
Electrothermal Model of SiC Power BJT
Authors: Patrzyk Joanna , Bisewski Damian , Zarębski Janusz
Published: May 2020

This paper refers to the issue of modelling characteristics of SiC power bipolar junction transistor (BJT), including the self-heating phenomenon. The electrothermal model of the tested device is demonstrated and experimentally verified. The electrical model is based on the isothermal Gummel–Poon model, but several modifications were made including the improved current gain factor (β) model and the modified model of the quasi-saturation region. The accuracy of the presented model was assessed by comparison of measurement and simulation results of selected characteristics of the BT1206-AC SiC BJT manufactured by TranSiC. In this paper, a single device characterization has only been performed. The demonstrated results of research show the evident temperature impact on the transistor d.c. characteristics. A good compliance between the measured and calculated characteristics of the considered transistor is observed even in quasi-saturation mode.
Hydrothermal Liquefaction of Rice Straw Using Methanol as Co-Solvent
Authors: Yerrayya Attada , Shree Vishnu A. K. , Shreyas S. , Chakravarthy S. R. , Vinu Ravikrishnan
Published: May 2020

Hydrothermal liquefaction (HTL) is a promising thermochemical process to treat wet feedstocks and convert them to chemicals and fuels. In this study, the effects of final temperature (300, 325, and 350 °C), reaction time (30 and 60 min), rice-straw-to-water ratio (1:1, 1:5, 1:10, and 1:15 (wt./wt.)), methanol-to-water ratio (0:100, 25:75, 50:50, and 75:25 (vol.%/vol.%)), and alkali catalysts (KOH, NaOH, and K2CO3) on product yields, composition of bio-crude, higher heating value (HHV) of bio-crude and bio-char, and energy recovery on HTL of rice straw are investigated. At the optimal processing condition corresponding to the final temperature of 300 °C, 60 min reaction time, and rice-straw-to-water ratio of 1:10 at a final pressure of 18 MPa, the bio-crude yield was 12.3 wt.% with low oxygen content (14.2 wt.%), high HHV (35.3 MJ/kg), and good energy recovery (36%). The addition of methanol as co-solvent to water at 50:50 vol.%/vol.% improved the yield of bio-crude up to 36.8 wt.%. The selectivity to phenolic compounds was high (49%–58%) when only water was used as the solvent, while the addition of methanol reduced the selectivity to phenolics (13%–22%), and improved the selectivity to methyl esters (51%–73%), possibly due to esterification reactions. The addition of KOH further improved the yield of bio-crude to 40 wt.% in an equal composition of methanol:water at the optimal condition. The energy-consumption ratio was less than unity for the methanol and catalyst system, suggesting that the process is energetically feasible in the presence of a co-solvent.
Impact of Sloshing on Fossil Fuel Loss during Transport
Authors: Mir Hafsa , Abdul Hussain Ratlamwala Tahir , Hussain Ghulam , Alkahtani Mohammed , Abidi Mustufa Haider
Published: May 2020

This study attempts to uncover the most common issue of fuel shortage faced by the oil and transportation industry worldwide. In Pakistan, petroleum is transported to the northern areas from the south coast. Currently, this is done using road tankers as a pipeline is still under construction. However, even after the pipeline becomes operative, road tankers would still be used for intra-city transport. Findings from this study can be used to determine the inter-city transport losses faced by oil companies. This study determines the hydrocarbons lost to the environment during inter-city road transport of petroleum. It takes nearly 2–3 days to complete a one-way trip with the fully loaded tank. Much work has been reported worldwide on hydrocarbon emissions, but nearly all of it has been done either for storage tanks/vessels or fuel tanks in rails/cars. The aim of this study was to investigate the actual amount of fuel lost to the environment due to the sloshing of liquid. Also, the results were expected to help in determining the extent of hazardous emissions resulting from road transport of petroleum. Hence, measures could be taken by the concerned authorities to mitigate the emissions if they exceeded the acceptable range. The sloshing was not found to contribute much in terms of vapor loss. Valve location was found to be important as no loss was obtained from the third compartment because the valve is to the right in this chamber. A negligible amount of fuel was lost from the first and second compartments per application of the brakes. Over a whole trip of 2–3 days, if the tanker braked 500 times, a total of 9–10 L would be lost to the environment.
The Flow Characteristics of Supercritical Carbon Dioxide (SC-CO2) Jet Fracturing in Limited Perforation Scenarios
Authors: Cai Can , Xie Song , Liu Qingren , Kang Yong , Lian Dong , Li Banrun
Published: May 2020

Supercritical carbon dioxide (SC-CO2) jet fracturing is a promising alternative for shale gas fracturing instead of water. However, most studies pay more attention to the fracture generation and ignore the flow characteristic of SC-CO2 jet fracturing in limited perforation scenarios. To accurately explore the flow field in a limited perforation tunnel, a numerical model of a SC-CO2 jet in a limited perforation tunnel before fracture initiation is established based on the corresponding engineering background. The comparison between the numerical simulation and experiments has proved that the model is viable for this type of analysis. By using the numerical method, the flow field of the SC-CO2 jet fracturing is analyzed, and influencing factors are discussed later. The verification and validation show that the numerical model is both reliable and accurate. With the dramatic fluctuating of turbulent mixing in a fully developed region, there is an apparent increase in the CO2 density and total pressure during limited perforation. When the z increases from 10 times r0 to 145 times r0, the velocity on the perforation wall surface would decrease below 0 m/s, resulting in backflow in the perforation tunnel. The structure of the nozzle, including the outlet length and outlet diameters, significantly affects the axial velocity and boosting pressure in the perforation tunnel. The highest total pressure exists when the nozzle length-to-radius ratio is 2. The maximum velocity of the jet core drops from 138.7 to 78 m/s, and the “hydraulic isolating ring” starts disappearing when the radius changes from 1 to 1.5 mm. It is necessary to increase the aperture ratio as much as possible to ensure pressurization but not over 1. Based on a similar theory high-speed photography results clearly show that the SC-CO2 develops to fully jetting in only 0.07 s and a strong mixing exists in the annular region between the jet core and the surroundings, according with the numerical simulation. This study should be helpful for scholars to comprehensively understand the interaction between the SC-CO2 jet and perforation, which is beneficial for studying SC-CO2 fracturing.
Optimal Operation Control of PV-Biomass Gasifier-Diesel-Hybrid Systems Using Reinforcement Learning Techniques
Authors: Kozlov Alexander N. , Tomin Nikita V. , Sidorov Denis N. , Lora Electo E. S. , Kurbatsky Victor G.
Published: May 2020

The importance of efficient utilization of biomass as renewable energy in terms of global warming and resource shortages are well known and documented. Biomass gasification is a promising power technology especially for decentralized energy systems. Decisive progress has been made in the gasification technologies development during the last decade. This paper deals with the control and optimization problems for an isolated microgrid combining the renewable energy sources (solar energy and biomass gasification) with a diesel power plant. The control problem of an isolated microgrid is formulated as a Markov decision process and we studied how reinforcement learning can be employed to address this problem to minimize the total system cost. The most economic microgrid configuration was found, and it uses biomass gasification units with an internal combustion engine operating both in single-fuel mode (producer gas) and in dual-fuel mode (diesel fuel and producer gas).
Generalized Energy and Ecological Characteristics of the Process of Co-Firing Coal with Biomass in a Steam Boiler
Authors: Kozioł Joachim , Czubala Joanna , Kozioł Michał , Ziembicki Piotr
Published: May 2020

One of the ways used to reduce the emission of carbon dioxide and other harmful substances is the implementation of biomass co-firing processes with coals. Such processes have been implemented for many years throughout many countries of the world, and have included using existing high-power coal boilers. Despite numerous experiments, there are still no analyses in the literature allowing for their generalization. The purpose of this paper is to determine the generalized energy and ecological characteristics of dust steam boilers co-firing hard coal with biomass. The energy characteristics determined in the paper are the dependence of the gross energy efficiency of boilers on such decision parameters as their efficiency and the share of biomass chemical energy in fuel. However, the ecological characteristics are the dependence of emission streams: CO, NOx, SO2, and dust on the same decision parameters. From a mathematical point of view, the characteristics are approximation functions between the efficiency values obtained from the measurements and the emission streams of the analysed harmful substances and the corresponding values of the decision parameters. Second-degree polynomials are assumed in this paper as approximation functions. Therefore, determining the characteristics came down to determining the constant coefficients occurring in these polynomials, the so-called structural parameters. The fit of the determined characteristics was assessed based on the coefficients of random variation and the test of estimated significance of structural parameters. Boiler characteristics can be used when forecasting the impact of changes in operating conditions on the effects achieved in existing, modernized, and designed boilers. The generalization of the characteristics was obtained from the measurement results presented in 10 independent sources used to determine them.
Li-Ion Batteries: A Review of a Key Technology for Transport Decarbonization
Authors: Stampatori Daniele , Raimondi Pier Paolo , Noussan Michel
Published: May 2020

Lithium ion batteries are experiencing an increased success thanks to their interesting performances, in particular for electric vehicles applications. Their continuous technological improvements in the last years are providing higher energy density and lower manufacturing costs. However, the environmental performance of their supply chain is of paramount importance to guarantee a cleaner alternative to fossil-based solutions on the entire life cycle of the applications. This paper carries out a comprehensive review on the main aspects related to Li-ion batteries manufacturing, to support the readers in understanding the complexity of the subject and the main challenges and opportunities for the future developments of this technology. The paper discusses the expected future demand of batteries; the main aspects related to the supply chain, including existing assets, input materials and alternative technologies; the end-of-life of batteries; the environmental impacts; and the main geopolitical implications.
Cost–Benefit Analysis of Measures to Reduce Windstorm Impact in Pure Norway Spruce (Picea abies L. Karst.) Stands in Latvia
Authors: Samariks Valters , Krisans Oskars , Donis Janis , Silamikele Ilze , Katrevics Juris , Jansons Aris
Published: May 2020

Wind is one of the major natural forest disturbances in Europe, and reduces the total economic (including carbon sequestration) value of forests. The aim of this study was to assess the financial benefit of silvicultural measures in young, pure, planted Norway spruce stands by reduction in the impact of wind damage over the rotation period. The analyzed measures are promptly applied precommercial thinning and low-density planting with improved plant material. Spatial information on factors affecting wind damage—wind climate and soil—were gathered and combined with the local growth model and empirical data from tree pulling experiments in Latvia to assess the economic value loss due to wind damage over a rotation period. Timely precommercial thinning and lower-density planting with improved plant material would ensure a positive net present value with an interest rate of 3%, using conservative estimates. The financial benefit is highest in windier (coastal) regions and for the planting, followed by moderate thinning. The results demonstrate that, even without changing the dominant tree species, a considerable reduction in wind-damage risk can be achieved.
Long-Term Adaption to High Osmotic Stress as a Tool for Improving Enological Characteristics in Industrial Wine Yeast
Authors: Betlej Gabriela , Bator Ewelina , Oklejewicz Bernadetta , Potocki Leszek , Górka Anna , Slowik-Borowiec Magdalena , Czarny Wojciech , Domka Wojciech , Kwiatkowska Aleksandra
Published: May 2020

Industrial wine yeasts owe their adaptability in constantly changing environments to a long evolutionary history that combines naturally occurring evolutionary events with human-enforced domestication. Among the many stressors associated with winemaking processes that have potentially detrimental impacts on yeast viability, growth, and fermentation performance are hyperosmolarity, high glucose concentrations at the beginning of fermentation, followed by the depletion of nutrients at the end of this process. Therefore, in this study, we subjected three widely used industrial wine yeasts to adaptive laboratory evolution under potassium chloride (KCl)-induced osmotic stress. At the end of the evolutionary experiment, we evaluated the tolerance to high osmotic stress of the evolved strains. All of the analyzed strains improved their fitness under high osmotic stress without worsening their economic characteristics, such as growth rate and viability. The evolved derivatives of two strains also gained the ability to accumulate glycogen, a readily mobilized storage form of glucose conferring enhanced viability and vitality of cells during prolonged nutrient deprivation. Moreover, laboratory-scale fermentation in grape juice showed that some of the KCl-evolved strains significantly enhanced glycerol synthesis and production of resveratrol-enriched wines, which in turn greatly improved the wine sensory profile. Altogether, these findings showed that long-term adaptations to osmotic stress can be an attractive approach to develop industrial yeasts.
Hepatic DNA Methylation in Response to Early Stimulation of Microbiota with Lactobacillus Synbiotics in Broiler Chickens
Authors: Dunislawska Aleksandra , Slawinska Anna , Siwek Maria
Published: May 2020

DNA methylation inhibits DNA transcription by the addition of methyl residues to cysteine within the CpG islands of gene promoters. The process of DNA methylation can be modulated by environmental factors such as intestinal microbiota. In poultry, the composition of the intestinal microbiota can be stimulated by in ovo delivery of synbiotics. The present study aims to determine the effect of Lactobacillus synbiotics delivered in ovo on the level of hepatic DNA methylation in broiler chickens. In ovo stimulation was performed on day 12 of egg incubation. Bioactive compounds delivered in ovo included (S1)—Lactobacillus salivarius with GOS and (S2)—Lactobacillus plantarum with RFO. Samples were collected from six individuals from each group on day 42 post-hatching. DNA methylation of five genes selected on the basis of the transcriptome data were analyzed using the qMSP method. Significant changes were observed in DNA methylation of genes in liver including ANGPTL4 and NR4A3, after S2 delivery. The obtained results confirm that the downregulation of metabolic gene expression in the liver mediated by in ovo stimulation had epigenetic characteristics.
Hydrogeology of Reclaimed Floodplain in A Permafrost Area, Yakutsk, Russia
Authors: Pavlova Nadezhda , Ogonerov Vasily , Danzanova Marina , Popov Vladimir
Published: May 2020

A study was performed to evaluate the current permafrost and groundwater conditions in the reclaimed floodplain of the Lena, one of the largest rivers in the permafrost zone. Data from ongoing hydrogeological monitoring were compared with earlier observations conducted during the reclamation process. The results demonstrate that the placement of dredged fill led to the development of suprapermafrost thaw zones (taliks). The anthropogenic taliks vary in thickness from 10 to 15 m in areas of buried bars to 20 m or more in the former locations of oxbow lakes. There is similarity in seasonal groundwater fluctuation patterns and response to river stage variations across the study area suggesting that a continuous aquifer connected to surface water. The connection with the river is most evident during the spring flood period. Two mechanisms of ground saturation are identified during this time. One is lateral seepage flow from the Lena River into the fill mass. The zone of its influence is limited to 150–170 m from the stream. The second is hydraulic pressure transmission from the river through the subchannel flow connected with the anthropogenic suprapermafrost aquifer. Its influence extends across the entire fill area. Continuous water movement at the base of the fill prevents permafrost aggradation from below. The study results should be taken into account when developing and implementing design and construction standards for engineering structures in the reclaimed floodplains of the permafrost zone.
Porphyroclasts: Source and Sink of Major and Trace Elements During Deformation-Induced Metasomatism (Finero, Ivrea-Verbano Zone, Italy)
Authors: Corvò Stefania , Langone Antonio , Padrón-Navarta José Alberto , Tommasi Andrea , Zanetti Alberto
Published: May 2020

Petrographic and geochemical data for mylonites from a metric-scale shear zone in mantle peridotites from the Finero massif (Southern Alps) record large mineralogical and geochemical modifications compared to surrounding coarse-grained ultramafic rocks, which were pervasively deformed in presence of hydrous melts. The mylonites are composed by olivine and orthopyroxene and, less frequently, clinopyroxene, phlogopite, and pargasite porphyroclasts enclosed in a fine-grained matrix of phlogopite and olivine, with subordinate amounts of orthopyroxene, clinopyroxene, pargasite, and chromite. P-T estimates indicate that deformation occurred under granulite- to upper-amphibolite facies conditions. Field relationships and U-Pb dating indicate that the shear zone was active during Lower Jurassic and/or later, in an extensional setting at the western margin of the Adria plate, which led to the opening of the Alpine Tethys. The major and trace element composition of the porphyroclasts in the mylonites significantly differ from those in the hosting coarse-grained ultramafics. Porphyroclasts were chemically active during deformation acting as source (diffusion-out) or sink (diffusion-in) for some trace elements. The chemical modifications were promoted by the interaction with aqueous fluids and the composition varied from mantle- (enriched in Ni, Co, Li, Na, REE, Y, and Sr) to crustal-derived (enriched in Zn, K, Al, Ti, and Fe).
Big Five, Self-Regulation, and Coping Strategies as Predictors of Achievement Emotions in Undergraduate Students
Authors: de la Fuente Jesús , Paoloni Paola , Kauffman Douglas , Yilmaz Soylu Meryem , Sander Paul , Zapata Lucía
Published: May 2020

The study focused on the analysis of linear relations between personality, self-regulation, coping strategies and achievement emotions. The main objective was to establish a model of linear, empirical, associative to infer needs and proposals for intervening in emotional health in the different profiles of university students. A total of 642 undergraduate students participated in this research. Evidence of associative relations between personality factors, self-regulation and coping strategies was found. The neuroticism factor had a significant negative associative relationship with Self-Regulation both globally and in its factors; especially important was its negative relation to decision making, and coping strategies focused in emotion. The results of Structural Equation Model showed an acceptable model of relationships, in each emotional context. Results and practical implications are discussed.
Epidemiologic Characteristics of Imported and Domestic Chikungunya Cases in Taiwan: A 13-Year Retrospective Study
Authors: Chou Yu-Ching , Hsieh Chi-Jeng , Cheng Chun-An , Wu Ding-Chung , Wu Wen-Chih , Lin Fu-Huang , Yu Chia-Peng
Published: May 2020

Background: Chikungunya fever is caused by the chikungunya virus. Numerous factors affect the risk of chikungunya transmission. This study explored the epidemiological characteristics, differences, and trends in domestic and imported cases of chikungunya fever in Taiwan in terms of patient sex, age, month of confirmation, and area of residence from 2007 to 2019. Methods: Public annual chikungunya data from Taiwan’s Centers for Disease Control (CDC) were analyzed. In total, 21 confirmed domestic and 198 imported cases of chikungunya were reported. Of the domestic cases, one was sporadic and reported in July 2019, and 20 were attributed to a cluster event during August and September 2019. Results: In a comparison between domestic and imported cases reported from July to October 2019, differences in sex were nonsignificant (p = 0.555), whereas significant differences were observed for age (p < 0.001), month of confirmation (p = 0.005), and place of residence (p = 0.001). An age of 69–69 years (odds ratio (OR) = 6.66, 95% confidence interval (95%CI) = 2.15–20.65), month of confirmation of September (OR = 5.25, 95%CI = 1.89–14.61) and place of residence of New Taipei City (OR = 48.70, 95%CI = 6.17–384.44) were identified as potential risk factors. Additionally, domestic cases in August and September 2019 increased in proportion to the increase in imported cases during July and August 2019. Increased domestic patients may have been caused by the domestic mosquitoes that transmitted the virus by biting the imported patients to Taiwan. This is the first report comparing domestic and imported cases of chikungunya from surveillance data from the Taiwan CDC from 2007 to 2019. Conclusion: This study highlights the importance of longitudinal and geographically extended studies to understand the implications of zoonotic disease transmission on Taiwan’s population. Critical data were identified to inform future surveillance and research efforts in Taiwan.
Work Related Musculoskeletal Pain in Golf Caddies—Johannesburg, South Africa
Authors: Garnett Jennica , Made Felix , Tlotleng Nonhlanhla , Wilson Kerry , Naicker Nisha
Published: May 2020

Golf is an important and growing industry in South Africa that currently fosters the creation of an informal job sector of which little is known about the health and safety risks. The purpose of the study is to investigate the prevalence and significance of musculoskeletal pain in male caddies compared to other golf course employees while holding contributing factors such as socioeconomic status, age, and education constant. Cross-sectional data were collected and analyzed from a convenience sample of 249 caddies and 74 non-caddies from six golf courses in Johannesburg, South Africa. Structural interviews were conducted to collect data on general demographics and musculoskeletal pain for two to three days at each golf course. On average, caddies were eight years older, had an income of 2880 rand less a month, and worked 4 h less a shift compared to non-caddies employed at the golf courses. Caddies were approximately 10% more likely to experience lower back and shoulder pain than non-caddies. Logistic regression models show a significantly increased adjusted odds ratio for musculoskeletal pain in caddies for neck (3.29, p = 0.015), back (2.39, p = 0.045), arm (2.95, p = 0.027), and leg (2.83, p = 0.019) compared to other golf course workers. The study findings indicate that caddying, as a growing informal occupation is at higher risk for musculoskeletal pain in caddies. Future policy should consider the safety of such a vulnerable population without limiting their ability to generate an income.
Application of Geophysical and Hydrogeochemical Methods to the Protection of Drinking Groundwater in Karst Regions
Authors: Song Kai , Yang Guangxu , Wang Fei , Liu Jian , Liu Dan
Published: May 2020

To provide theoretical support for the protection of centralized drinking groundwater sources in karst areas, it is necessary to accurately identify the development of karst conduits and analyze the differences in hydrogeochemical characteristics of different karst systems. This provides a scientific basis for the accurate designation of risk zones that may cause drinking groundwater pollution. In this study, a geophysical survey, hydrogeological chemical process analysis and optimized fuzzy cluster analysis were used to gradually improve the understanding of karst water systems. AMT and HDR methods were used to calibrate the resistivity around the water-filling karst conduits, which ranged from 39 to 100 Ω·m. A total of seven karst systems were identified, including four karst systems in the north of the study area, one karst system in the west and two karst systems in the south. Analysis of the hydrochemical data showed that HCO3-Ca and HCO3-Mg-Ca types accounted for 90% of all samples. The δD and δ18O values of their main conduits were −51.70‰ to −38.30‰ and −7.99‰ to −5.96‰, respectively. The optimized fuzzy clustering analysis method based on the weight of variables assigned by AHP more accurately verified karst water systems. Based on these findings, the drinking groundwater source risk zone was designated with an area of 33.90 km2, accounting for 34.5% of the study area. This study effectively improved the rationality and accuracy of the designation of drinking groundwater source risk zones in karst areas, and provided a scientific basis for the identification of karst water systems and decision-making of drinking groundwater source protection in karst areas.