bluuebunny/crossref_metadata_2025 huggingface dataset:
Предпосылки создания межконтинентальной зоны свободной торговли между Европейским союзом и Африканским союзом (1963 – 2020 гг.)
Authors: Зинченко А. Н.
Published: December 2020

В статье рассматриваются отношения между Европейским союзом и странами Африки к югу от Сахары, а также интеграционные процессы в Европе и Африке, которые привели к заключению ряда соглашений об экономическом партнерстве и образованию Африканской континентальной зоны свободной торговли, Также сделана попытка спрогнозировать будущие интеграционные процессы между Европейским союзом и странами Африки, которые могут привести к образованию первой в своем роде межконтинентальной зоны свободной торговли ЕС – Африка.
В исследовании был использован широкий круг научной литературы и источников, включая научные публикации научно-исследовательских и аналитических центров, а также отечественных и зарубежных исследователей. В статье изучается эволюция отношений между европейскими и африканскими странами, отмечается постепенное развитие регионального подхода Европейского союза при заключении соглашений об экономическом партнерстве. Также изучена эволюция интеграционных объединений в Африке, предпосылки создания континентальной зоны свободной торговли в Африке, а также роль региональных объединений и континентальной зоны свободной торговли для будущего создания интеграционного объединения Европейского и Африканского союзов.
Development of interactive media based on videoscribe with realistic mathematics education approach to navigation
Authors: Astriawati Ningrum
Published: December 2020

Penelitian ini mempunyai tujuan untuk mengembangkan media pembelajaran interaktif berbasis software sparkol videoscribe dengan model pendekatan Realistic Mathematics Education (RME) bidang navigasi pelayaran. Penelitian ini merupakan penelitian Research and Development (R&D) menggunakan metode ADDIE (Analysis, Design, Development, Implementation And Evaluation). Dalam menguji hasil media yang telah dikembangkan menggunakan pola one-group pretest- posttest design. Teknik pengumpulan data menggunakan teknik kuesioner, teknik observasi, dan teknik wawancara. Teknik analisis data menggunakan analisis deskriptif kuantitatif. Kategori  kualitas  produk menggunakan kategori Nieveen yaitu  (1)  valid,  (2)  praktis,  dan  (3)  efektif.  Hasil penelitian pengembangan media pembelajaran interaktif berbasis software sparkol videoscribe dengan model pendekatan Realistic Mathematics Education (RME) bidang navigasi pelayaran menunjukkan kategori valid, praktis dan efektif untuk meningkatkan motivasi belajar taruna.
Technical and Vocational Education has become a subject of discussion among the stakeholders in Nepal. Though TVET had been introduced for a considerable length of time. it has not been instituted and developed to meet the needs of the evolving context. The mandate of handling the TVET sector up to the secondary level has been entrusted to the local government institutions according to the federal constitution of Nepal but central authorities seem not prepared to loosen their grip on it. This has given rise to several confusions and ambiguities in both the policy and operational realm. Roughly 384 community based technical schools are running in the country to date. At the same time, TECS has attempted to promote and establish a technical wing in the community schools from the center. This has presented problems as it goes against the provision envisaged in the federal constitution of Nepal.
Authors: Rijal Nimananda , Rijal Mukti
Published: December 2020

This is an overview of Technical, Vocational Education and Training. Nepal has a federal structure of governance but they are not fully exercised their duties provided by the constitution, still, there is a grip from the central level. The study will empower the local and provincial governments to establish technical institutes as per the requirement of the local community. The study is carried out with the published journal, history of TVET in Nepal, Constitution of Nepal, and other relevant articles published nationally and Internationally. Still, the central level of control discovered in distributing Technical Schools to the local government, and CTEVT also providing affiliation to the community schools, they do not have any correlation with one another. It has recommended to the local governments to establish full-fledged technical institutes which are in their jurisdictions and the local level need of the required human resources will be produced.
Perception of Nurses on the Establishment, and their Willingness to Work in Assisted Living Facilities in Ghana
Authors: Irene Korkoi Aboh
Published: December 2020

Aim: This study explored the perception of Ghanaian nurses on the establishment and their willingness to work in assisted living facilities. Methods The study used a mixed-methods approach in which qualitative data was collected first before the quantitative data. Data was collected through Focused Group Discussions (FGDs) and questionnaires from 248 respondents with age ranging from 20 to 58 years from October 2016 to January 2017 with 8 missing from the quantitative data. Four pertinent questions were asked in both set of data. Sampling was convenient and purposive from 4 different health facilities in the metropolis. Data from the FGDs were digitally recorded and transcribed verbatim. Quantitative data was entered in SPSS version 23 and cleaned. Both sets of data were coded and analyzed. Results The nurses appreciated the increase in the number of the aged in their communities; they think community members prepare towards their ageing by using their children as security, and the idea of assisted living was enthusiastically supported by 66% of the population, but with the proviso that it would need to be ran by a private entrepreneur, then they would be willing to work in such a facility. Discussion: The nurses also think that families are now becoming more nuclear; that is why caring for the aged has become a problem, thus creating a need for assisted living facilities.
Characterizing the Foreshock, Main Shock, and Aftershock Sequences of the Recent Major Earthquakes in Southern Alaska, 2016–2018
Authors: Bukchin B. G. , Fomochkina A. S. , Kossobokov V. G. , Nekrasova A. K.
Published: December 2020

For each of three major M ≥ 7.0 earthquakes (i.e., the January 24, 2016, M7.1 earthquake 86 km E of Old Iliamna; the January 23, 2018, M7.9 earthquake 280 km SE of Kodiak; and the November 30, 2018, M7.1 earthquake 14 km NNW of Anchorage, Alaska), the study considers characterization of the foreshock and aftershock sequences in terms of their variations and scaling properties, including the behavior of the control parameterηof the unified scaling law for earthquakes (USLE), along with a detailed analysis of the surface wave records for reconstruction of the source in the approximation of the second moments of the stress glut tensor to obtain integral estimation of its length, orientation, and development over time. The three major earthquakes at 600 km around Anchorage are, in fact, very different due to apparent complexity of earthquake flow dynamics in the orogenic corner of the Pacific and North America plate boundary. The USLE generalizes the classic Gutenberg-Richter relationship taking into account the self-similar scaling of the empirical distribution of earthquake epicenters. The study confirms the existence of the long-term periods of regional stability of the USLE control parameter that are interrupted by mid- or even short-term bursts of activity associated with major catastrophic events.
Establishment of CRISPR/Cas9 Genome Editing in Witloof (Cichorium intybus var. foliosum)
Authors: De Bruyn Charlotte , Ruttink Tom , Eeckhaut Tom , Jacobs Thomas , De Keyser Ellen , Goossens Alain , Van Laere Katrijn
Published: December 2020

Cichorium intybus var. foliosum (witloof) is an economically important crop with a high nutritional value thanks to many specialized metabolites, such as polyphenols and terpenoids. However, witloof plants are rich in sesquiterpene lactones (SL) which are important for plant defense but also impart a bitter taste, thus limiting industrial applications. Inactivating specific genes in the SL biosynthesis pathway could lead to changes in the SL metabolite content and result in altered bitterness. In this study, a CRISPR/Cas9 genome editing workflow was implemented for witloof, starting with polyethylene glycol (PEG) mediated protoplast transfection for CRISPR/Cas9 vector delivery, followed by whole plant regeneration and mutation analysis. Protoplast transfection efficiencies ranged from 20 to 26 %. A CRISPR/Cas9 vector targeting the first exon of the phytoene desaturase (CiPDS) gene was transfected into witloof protoplasts and resulted in the knockout of CiPDS, giving rise to an albino phenotype in 23% of the regenerated plants. Further implementing our protocol, the SL biosynthesis pathway genes germacrene A synthase (GAS), germacrene A oxidase (GAO), and costunolide synthase (COS) were targeted in independent experiments. Highly multiplex (HiPlex) amplicon sequencing of the genomic target loci revealed plant mutation frequencies of 27.3, 42.7, and 98.3% in regenerated plants transfected with a CRISPR/Cas9 vector targeting CiGAS, CiGAO, and CiCOS, respectively. We observed different mutation spectra across the loci, ranging from consistently the same +1 nucleotide insertion in CiCOS across independent mutated lines, to a complex set of 20 mutation types in CiGAO across independent mutated lines. These results demonstrate a straightforward workflow for genome editing based on transfection and regeneration of witloof protoplasts and subsequent HiPlex amplicon sequencing. Our CRISPR/Cas9 workflow can enable gene functional research and faster incorporation of novel traits in elite witloof lines in the future, thus facilitating the development of novel industrial applications for witloof.
A Diversity of Intrinsic Timescales Underlie Neural Computations
Authors: Cavanagh Sean E. , Hunt Laurence T. , Kennerley Steven W.
Published: December 2020

Neural processing occurs across a range of temporal scales. To facilitate this, the brain uses fast-changing representations reflecting momentary sensory input alongside more temporally extended representations, which integrate across both short and long temporal windows. The temporal flexibility of these representations allows animals to behave adaptively. Short temporal windows facilitate adaptive responding in dynamic environments, while longer temporal windows promote the gradual integration of information across time. In the cognitive and motor domains, the brain sets overarching goals to be achieved within a long temporal window, which must be broken down into sequences of actions and precise movement control processed across much shorter temporal windows. Previous human neuroimaging studies and large-scale artificial network models have ascribed different processing timescales to different cortical regions, linking this to each region’s position in an anatomical hierarchy determined by patterns of inter-regional connectivity. However, even within cortical regions, there is variability in responses when studied with single-neuron electrophysiology. Here, we review a series of recent electrophysiology experiments that demonstrate the heterogeneity of temporal receptive fields at the level of single neurons within a cortical region. This heterogeneity appears functionally relevant for the computations that neurons perform during decision-making and working memory. We consider anatomical and biophysical mechanisms that may give rise to a heterogeneity of timescales, including recurrent connectivity, cortical layer distribution, and neurotransmitter receptor expression. Finally, we reflect on the computational relevance of each brain region possessing a heterogeneity of neuronal timescales. We argue that this architecture is of particular importance for sensory, motor, and cognitive computations.
Effect of Different Rates of Nitrogen Fertilization on Crop Yield, Soil Properties and Leaf Physiological Attributes in Banana Under Subtropical Regions of China
Authors: Sun Jianbo , Li Wenbin , Li Chunqiang , Chang Wenjun , Zhang Shiqing , Zeng Yanbo , Zeng Changying , Peng Ming
Published: December 2020

Excessive nitrogen (N) application is widespread in Southern China. The effects of N fertilization on soil properties and crop physiology are poorly understood in tropical red loam soil. We conducted a field experiment to evaluate the effect of nitrogen fertilization rates on physiological attributes (chlorophyll, plant metabolic enzymes, soluble matters) on banana leaves, soil properties (soil enzymes, soil organic matter (SOM), soil available nutrients) as well as banana crop yield in a subtropical region of southern China. The N rates tested were 0 (N0), 145 (N145), 248 (N248), 352 (N352), 414 (NFT), and 455 (N455) g N per plant. The correlations among soil factors, leaf physiological factors and crop yield were evaluated. The results indiated that the high rates of N fertilization (NFTand N455) significantly decreased soil available potassium (K) content, available phosphorus (P) content, glutamine synthetase (GS) activity, and soluble protein and sugar contents compared with lower N rates. The N352treatment had the highest crop yields compared with higher N rates treatments, followed by the N455treatment. However, there were no significant differences in crop yields among N fertilization treatments. Factor analysis showed that the N352treatment had the highest integrated score for soil and leaf physiological factors among all treatments. Moreover, the N352treatment was the most effective in improving carbon and nitrogen metabolism in banana. Crop yield was significantly and positively linearly correlated with the integrated score (r= 0.823,p< 0.05). Path analysis revealed that invertase, SOM and sucrose synthase (SS) had a strong positive effect on banana yield. Canonical correspondence analysis (CCA) suggested that available K, invertase, acid phosphatase and available P were the most important factors impacting leaf physiological attributes. Cluster analysis demonstrated distinct differences in N application treatment related to variations in soil and leaf factors. This study suggested that excessive N fertilization had a negative effect on soil fertility, crop physiology and yield. The lower N rates were more effective in improving crop yield than higher rates of N fertilization. The N rate of 352 g N per plant (N352) was recommended to reduce excess N input while maintaining the higher yield for local farmers’ banana planting.
Suicide in Psychiatric Inpatients— A Case–Control Study
Authors: Deisenhammer Eberhard A. , Behrndt-Bauer Elisa-Marie , Kemmler Georg , Haring Christian , Miller Carl
Published: December 2020

Objective: Psychiatric inpatients constitute a population at considerably increased risk for suicide. Identifying those at imminent risk is still a challenging task for hospital staff. This retrospective case–control study focused on clinical risk factors related to the course of the hospital stay.

Method: Inpatient suicide cases were identified by linking the Tyrol Suicide Register with the registers of three psychiatric hospitals in the state. Control subjects were patients who had also been hospitalized in the respective psychiatric unit but had not died by suicide. Matching variables included sex, age, hospital, diagnosis, and admission date. The study period comprised 7 years. Data were analyzed by the appropriate two-sample tests and by logistic regression.

Results: A total of 30 inpatient suicide cases and 54 control patients were included. A number of factors differentiated cases from controls; after correction for multiple testing, the following retained significance: history of aborted suicide, history of attempted suicide, history of any suicidal behavior/threats, suicidal ideation continuing during hospitalization, no development of prospective plans, no improvement of mood during the hospital stay, and leaving ward without giving notice. Logistic regression identified the latter three variables and history of attempted suicide as highly significant predictors of inpatient suicide.

Conclusions: Preventive measures during hospitalization include thorough assessment of suicidal features, an emphasis on the development of future perspectives, and a review of hospital regulations for patients who want to leave the ward.
Sampling-Based Motion Planning for Free-Floating Space Robot without Inverse Kinematics
Authors: Zhang Hongwen , Zhu Zhanxia
Published: December 2020

Motion planning is one of the most important technologies for free-floating space robots (FFSRs) to increase operation safety and autonomy in orbit. As a nonholonomic system, a first-order differential relationship exists between the joint angle and the base attitude of the space robot, which makes it pretty challenging to implement the relevant motion planning. Meanwhile, the existing planning framework must solve inverse kinematics for goal configuration and has the limitation that the goal configuration and the initial configuration may not be in the same connected domain. Thus, faced with these questions, this paper investigates a novel motion planning algorithm based on rapidly-exploring random trees (RRTs) for an FFSR from an initial configuration to a goal end-effector (EE) pose. In a motion planning algorithm designed to deal with differential constraints and restrict base attitude disturbance, two control-based local planners are proposed, respectively, for random configuration guiding growth and goal EE pose-guiding growth of the tree. The former can ensure the effective exploration of the configuration space, and the latter can reduce the possibility of occurrence of singularity while ensuring the fast convergence of the algorithm and no violation of the attitude constraints. Compared with the existing works, it does not require the inverse kinematics to be solved while the planning task is completed and the attitude constraint is preserved. The simulation results verify the effectiveness of the algorithm.
Big Data and Actuarial Science
Authors: Hassani Hossein , Unger Stephan , Beneki Christina
Published: December 2020

This article investigates the impact of big data on the actuarial sector. The growing fields of applications of data analytics and data mining raise the ability for insurance companies to conduct more accurate policy pricing by incorporating a broader variety of data due to increased data availability. The analyzed areas of this paper span from automobile insurance policy pricing, mortality and healthcare modeling to estimation of harvest-, climate- and cyber risk as well as assessment of catastrophe risk such as storms, hurricanes, tornadoes, geomagnetic events, earthquakes, floods, and fires. We evaluate the current use of big data in these contexts and how the utilization of data analytics and data mining contribute to the prediction capabilities and accuracy of policy premium pricing of insurance companies. We find a high penetration of insurance policy pricing in almost all actuarial fields except in the modeling and pricing of cyber security risk due to lack of data in this area and prevailing data asymmetries, for which we identify the application of artificial intelligence, in particular machine learning techniques, as a possible solution to improve policy pricing accuracy and results.
Indirect Galvanostatic Pulse in Wenner Configuration: Numerical Insights into Its Physical Aspect and Its Ability to Locate Highly Corroding Areas in Macrocell Corrosion of Steel in Concrete
Authors: Rodrigues Romain , Gaboreau Stéphane , Gance Julien , Ignatiadis Ioannis , Betelu Stéphanie
Published: December 2020

The use of indirect electrical techniques is gaining interest for monitoring the corrosion of steel in concrete as they do not require any connection to the rebar. In this paper, we provide insights into the physical aspects of the indirect galvanostatic pulse (GP) method in the Wenner configuration. Considering uniform corrosion, the instantaneous ohmic drop is decreased due to the presence of the rebar, which acts as a short-circuit. However, we observed that this phenomenon is independent of the electrochemical parameters of the Butler–Volmer equation. They are, however, responsible for the nonlinear decrease of the current that polarizes the rebar over time, especially for a passive rebar due to its high polarization resistance. This evolution of the resulting potential difference with time is explained by the increase of the potential difference related to concrete resistance and the global decrease of the potential difference related to the polarization resistance of the rebar. The indirect GP technique is then fundamentally different than the conventional one in three-electrode configuration, as here the steady-state potential is not only representative of polarization resistance but also of concrete resistance. Considering non-uniform corrosion, the presence of a small anodic area disturbs the current distribution in the material. This is essentially due to the different capability of anodic and cathodic areas to consume the impressed current, resulting in slowing down the evolution of the transient potential as compared to uniform corrosion. Hence, highly corroding areas have a greater effect on the transient potential than on the steady-state one. The use of this temporal evolution is thus recommended to qualitatively detect anodic areas. For the estimation of their length and position, which is one of the main current problematic issue when performing any measurement on reinforced concrete (RC) structures with conventional techniques, we suggest adjusting the probe spacing to modulate the sensitivity of the technique.
Measuring the Coupling Direction between Neural Oscillations with Weighted Symbolic Transfer Entropy
Authors: Li Zhaohui , Li Shuaifei , Yu Tao , Li Xiaoli
Published: December 2020

Neural oscillations reflect rhythmic fluctuations in the synchronization of neuronal populations and play a significant role in neural processing. To further understand the dynamic interactions between different regions in the brain, it is necessary to estimate the coupling direction between neural oscillations. Here, we developed a novel method, termed weighted symbolic transfer entropy (WSTE), that combines symbolic transfer entropy (STE) and weighted probability distribution to measure the directionality between two neuronal populations. The traditional STE ignores the degree of difference between the amplitude values of a time series. In our proposed WSTE method, this information is picked up by utilizing a weighted probability distribution. The simulation analysis shows that the WSTE method can effectively estimate the coupling direction between two neural oscillations. In comparison with STE, the new method is more sensitive to the coupling strength and is more robust against noise. When applied to epileptic electrocorticography data, a significant coupling direction from the anterior nucleus of thalamus (ANT) to the seizure onset zone (SOZ) was detected during seizures. Considering the superiorities of the WSTE method, it is greatly advantageous to measure the coupling direction between neural oscillations and consequently characterize the information flow between different brain regions.
Attention to Diversity in Compulsory Secondary Education
Authors: Varela Elia Vázquez , Portela Pino Iago , Rodríguez Víctor Domínguez
Published: December 2020

The attention to pupil diversity is still considered one of the main issues to solve in the current educational system. The objective of the study was to establish and analyze the differences between the knowledge and the use of ordinary and extraordinary measures in the attention to diversity from the point of view of compulsory secondary education teachers. A descriptive study was performed with a quantitative methodology, making use of a 452-teacher sample (Mean: 47, Standard Deviation: 8.42) using a survey. The results show a better understanding and frequency of use of the ordinary measures compared to the extraordinary ones. Results also maintain that among the most used we found the adequacy of the didactic planning as well as the support of the therapeutic pedagogy and language and auditory specialist. Moreover, the analysis reveals that the CMOEAD (ordinary and extraordinary measures for the attention to diversity) survey possesses psychometric properties which support its use in further studies. In conclusion, a better knowledge and use of ordinary and extraordinary measures in attention to diversity enables a forward leap in the quality and equity for pupils.
Research of Particle Motion in a Two-Stage Slurry Transport Pump for Deep-Ocean Mining by the CFD-DEM Method
Authors: Su Xianghui , Tang Zhenji , Li Yi , Zhu Zuchao , Mianowicz Kamila , Balaz Peter
Published: December 2020

The slurry transport pump is the key equipment of deep-ocean mining systems. The motion law of coarse particles in the pump is not clear enough. In this paper, a hydraulic model of a laboratory-scale two-stage slurry transport pump is constructed, and the motion characteristics of coarse particles in the pump are numerically studied by using the computational fluid dynamics–discrete element method (CFD-DEM) method. The performance curve of the pump is obtained by experimental measurement, and the reliability of the calculated results is verified. Due to the application of the amplification flow rate design method, the optimum efficiency point of the pump is shifted to the large flow rate condition. Differences in particle swarm within two stages are compared. The position distribution, velocity variation and trajectory of particles in the impeller and bowl diffuser are studied in detail. The velocity of particles leaving the impeller depends on whether they collide with the impeller blade. The motion of particles in the bowl diffuser is divided into three periods. Collision between particles and blades in the bowl diffuser not only leads to energy loss but also gradually transforms the circumferential velocity of particles into axial velocity in the second period. This work can provide a reference for the study of wear and blockage prevention of slurry transport pumps.
A Genetic Algorithm Approach as a Self-Learning and Optimization Tool for PV Power Simulation and Digital Twinning
Authors: Guzman Razo Dorian Esteban , Müller Björn , Madsen Henrik , Wittwer Christof
Published: December 2020

A key aspect for achieving a high-accuracy Photovoltaic (PV) power simulation, and reliable digital twins, is a detailed description of the PV system itself. However, such information is not always accurate, complete, or even available. This work presents a novel approach to learn features of unknown PV systems or subsystems using genetic algorithm optimization. Based on measured PV power, this approach learns and optimizes seven PV system parameters: nominal power, tilt and azimuth angles, albedo, irradiance and temperature dependency, and the ratio of nominal module to nominal inverter power (DC/AC ratio). By optimizing these parameters, we create a digital twin that accurately reflects the actual properties and behaviors of the unknown PV systems or subsystems. To develop this approach, on-site measured power, ambient temperature, and satellite-derived irradiance of a PV system located in south-west Germany are used. The approach proposed here achieves a mean bias error of about 10% for nominal power, 3° for azimuth and tilt angles, between 0.01%/C and 0.09%/C for temperature coefficient, and now-casts with an accuracy of around 6%. In summary, we present a new solution to parametrize and simulate PV systems accurately with limited or no previous knowledge of their properties and features.
Ageing Tests of Samples of Glass-Epoxy Core Rods in Composite Insulators Subjected to High Direct Current (DC) Voltage in a Thermal Chamber
Authors: Wieczorek Krzysztof , Ranachowski Przemysław , Ranachowski Zbigniew , Papliński Piotr
Published: December 2020

In this article, we presented the results of the tests performed on three sets of samples of glass-reinforced epoxy (GRE) core rods used in alternating current (AC) composite insulators with silicone rubber housing. The objective of this examination was to test the aging resistance of the rod material when exposed to direct current (DC) high voltage. We hypothesized that the long-term effects of the electrostatic field on the GRE core rod material would lead to a gradual degradation of its mechanical properties caused by ionic current flow. Further, we hypothesized that reducing the mechanical strength of the GRE core rod would lead to the breakage of the insulator. The first group of samples was used for reference. The samples from the second group were subjected to a temperature of about 50 °C for 6000 h. The third group of samples were aged by temperature and DC high voltage for the same time. The samples were examined using the 3-point bending test, micro-hardness measurement and microscopic analysis. No recordable degradation effects were found. Long-term temperature impact and, above all, the combined action of temperature and DC high voltage did not reduce the mechanical parameters or change the microstructure of the GRE material.
Experimental Determination of the Influence of Shape on the Heat Transfer Process in a Crushed Granite Storage Bed
Authors: Nemś Magdalena
Published: December 2020

The article presents the problem of modelling the charging of a constant-phase bed storage in the first hours of the process. The places of errors in the heat transfer calculations for the packed beds were indicated. Granite in the shape of spheres and crushed rocks, with a characteristic dimension of 50 mm, was used for the experimental tests. The material was subjected to tomographic examination and then used as a storage material. The charging process was carried out for three flow rates: 0.006, 0.008 and 0.010 m3/s. After three hours of testing, the temperature of the outlet air for the granite sphere as the storage material was the same as for the granite crushed rock. However, the biggest differences occurred after 1 h of charging. They were equal to: 40.4% for the flow rate of 0.006 m3/s, 22.0% for the flow rate of 0.008 m3/s, and 18.5% for the flow rate of 0.010 m3/s. The differences were greater than the uncertainty of the measurements. As a result, different temperatures of the storage material were obtained. After three hours, they were equal to: 25.2%, 12.3% and 8.6% for the lowest, medium, and highest airflow, respectively. The conducted heat transfer analysis and the relationship Nu = f(Re) was determined. The influence of the calculated and actual surface of the crushed rock on the heat exchange process was explained. For all the tested air flow rates through the bed, higher thermal parameters were obtained for the crushed rock than for the sphere. The maximum differences in the Nu number were: 222.6%, 151.4% and 161.3% for the flow of 0.006, 0.008 and 0.010 m3/s, respectively. This means that the description of the heat exchange process in the piled beds would require a parameter that takes into account the geometry of the storage material.
Airtightness Analysis of the Built Heritage–Field Measurements of Nineteenth Century Buildings through Blower Door Tests
Authors: Martín-Garín Alexander , Millán-García José Antonio , Hidalgo-Betanzos Juan María , Hernández-Minguillón Rufino Javier , Baïri Abderrahmane
Published: December 2020

Airtightness is a major issue in architectural design and it has a significant impact on the energy performance of buildings. Moreover, the energy behaviour of built heritage is due, to its singular characteristics, still a great unknown. The aim of this study is to establish a better knowledge of the airtightness of historical buildings, based on an in depth field study using blower-door tests. A set of 37 enclosures were analyzed inside eight buildings located in historical areas of a Spanish city with a significant built heritage. They were constructed between 1882 and 1919 and include diverse construction typologies applied for many building uses such as residential, cultural, educational, administrative and emblematic. The results indicate lower values compared to other previous airtightness studies of historical buildings. The average air change rate was found to be n50 = 9.03 h−1 and the airtightness of the enclosures presented a wide range of between 0.68 and 37.12 h−1. Three main levels of airtightness were identified with two thirds of the tested samples belonging to the intermediate level between 3–20 h−1. To conclude, several correlations have been developed which provide a method to estimate air leakage and could serve as a basis for energy performance studies of these kinds of building.
Optimal Operation for Integrated Electricity–Heat System with Improved Heat Pump and Storage Model to Enhance Local Energy Utilization
Authors: Chen Yang , Zhang Yao , Wang Jianxue , Lu Zelong
Published: December 2020

As the need for clean energy increases, massive distributed energy resources are deployed, strengthening the interdependence of multi-carrier energy systems. This has raised concerns on the electricity-heat system’s co-operation for lower operation costs, higher energy efficiency, and higher flexibility. This paper discusses the co-operation of integrated electricity–heat system. In the proposed model, network constraints in both systems are considered to guarantee system operations’ security: the branch flow model is utilized to describe the electricity network, while a convexified model considering variable mass flow and temperature dynamics is adopted to describe the heat network. Additionally, novel models for heat pumps and the stratified water tank are proposed to represent the physical system more accurately. Finally, to preserve the information privacy of separate systems, a distributed algorithm is proposed based on the alternating direction method of multipliers (ADMM). Numerical studies show that the co-operation could provide a more economical and reliable solution than the decoupled operation of the heat network and electricity network. Moreover, the ADMM-based algorithm could derive solutions very close to the optimum provided by centralized optimization.
CsPbBr3 Nanocrystals-Based Polymer Nanocomposite Films: Effect of Polymer on Spectroscopic Properties and Moisture Tolerance
Authors: Fanizza Elisabetta , Schingo Roberto , Panniello Annamaria , Lanza Angelica Maria , Depalo Nicoletta , Agostiano Angela , Curri Maria Lucia , Striccoli Marinella
Published: December 2020

Metal halide perovskites nanocrystals (NCs) represent an emerging class of materials that find increasing application in optoelectronic and photovoltaic devices, thanks to their intriguing optical properties, including high absorption coefficient, high fluorescence quantum yield (PL QY) and fast charge carrier separation. However, their opening to market is still hindered by their limited reliability, due to an intrinsic structural instability and degradation of their photophysical properties upon air, moisture, and light exposure. The incorporation of perovskite NCs in polymer matrix can limit some of the NC instability issues, with advantages in film processability, device fabrication and mechanical performance, being also useful for fundamental studies. In this regard, here, nanocomposites based on polymethylmethacrylate or polystyrene embedding all-inorganic CsPbBr3 NCs have been prepared and processed in the form of flexible free-standing films. A systematic spectrofluorimetric study, comprising steady state photoluminescence (PL), PL quantum yield (QY) and PL decay of the free-standing films before and after exposure to relative humidity condition (RH% 85%, at 25 °C) is performed and discussed. Phase segregation phenomena, changes in NC passivation and recombination dynamics are evaluated as a function of polymer loading and its molecular structure and finally the efficacy of the polymer as moisture barrier investigated.
Increasing Energy Efficiency and Productivity of the Comminution Process in Tumbling Mills by Indirect Measurements of Internal Dynamics—An Overview
Authors: Góralczyk Mateusz , Krot Pavlo , Zimroz Radosław , Ogonowski Szymon
Published: December 2020

Tumbling mills have been widely implemented in many industrial sectors for the grinding of bulk materials. They have been used for decades in the production of fines and in the final stages of ore comminution, where optimal levels for the enrichment particles’ sizes are obtained. Even though these ubiquitous machines of relatively simple construction have been subjected to extensive studies, the industry still struggles with very low energy efficiency of the comminution process. Moreover, obtaining an optimal size for the grinding product particles is crucial for the effectiveness of the following processes and waste production reduction. New, innovative processing methods and machines are being developed to tackle the problem; however, tumbling mills are still most commonly used in all ranges of the industry. Since heavy equipment retrofitting is the most costly approach, process optimization with dedicated models and control systems is the most preferable solution for energy consumption reduction. While the classic technological measurements in mineral processing are well adopted by the industry, nowadays research focuses on new methods of the mill’s internal dynamics analysis and control. This paper presents a retrospective overview of the existing models of internal load motion, an overview of the innovations in process control, and some recent research and industrial approaches from the energy consumption reduction point of view.
Determining If Oil Prices Significantly Affect Renewable Energy Investment in African Countries with Energy Security Concerns
Authors: Tambari Ishaya , Failler Pierre
Published: December 2020

As concerns regarding the adverse impacts of energy production and consumption on the environment grow, countries across the world are now charged with developing effective strategies that provide energy security and protect the environment. This means that efforts to generate significant investments and business opportunities to boost the growth of renewable energy need to increase rapidly. However, there are limited studies on what will facilitate the increase of renewable energy investment in Africa. The main factor considered in this study relates to the sensitivity to changes in oil prices, gross domestic product (GDP), interest rate and oil price volatility’s impact on the renewable energy investment (REI) in countries with energy security concerns and if there is any significant influence from oil price shocks. With the help of an unrestricted vector retrogressive model and an annual panel data approach that covers the period 1990–2018, this paper examines the link between renewable energy investment and three macroeconomic variables: oil prices, GDP growth-adjusted interest rates and oil price volatility. The results indicate that REI exhibited immediate positive responses to oil shocks. However, renewable energy investment continued to fluctuate negatively in response to GDP. The results also show that the REI responded positively to interest rates in Africa and it exhibited immediate negative responses to oil price volatility but became positive after the second period.
Patent Analysis on the Development of the Shale Petroleum Industry Based on a Network of Technological Indices
Authors: Kim Jong-Hyun , Lee Yong-Gil
Published: December 2020

This study investigated the technological developments in the shale petroleum industry by analyzing patent data using a network of technological indices. The technological developments were promoted by the beginning of the shale industry, and after the first five years, it showed a more complex development pattern with the convergence of critical technologies. This paper described progress in the shale petroleum technologies as changes in relatedness networks of technological components. The relatedness represents degree of convergence between technological components, and betweenness centrality of network represents priority of technological components. In the results, the progress of the critical technologies such as directional drilling, increasing permeability, and smart systems, were actively carried out from 2012 to 2016. Especially, unconverged technology of increasing permeability and the converged technology of directional drilling and smart system has been intensively developed. Some technological components of the critical technologies are more significant in the form of converged technology.
Process Monitoring in Heavy Duty Drilling Rigs—Data Acquisition System and Cycle Identification Algorithms
Authors: Wodecki Jacek , Góralczyk Mateusz , Krot Pavlo , Ziętek Bartłomiej , Szrek Jaroslaw , Worsa-Kozak Magdalena , Zimroz Radoslaw , Śliwiński Paweł , Czajkowski Andrzej
Published: December 2020

The monitoring of drilling processes is a well-known topic in the mining industry. It is widely used for rock mass characterization, bit wear monitoring and drilling process assessment. However on-board monitoring systems used for this purpose are installed only on a limited number of machines, and breakdowns are possible. There is a need for a data acquisition system that can be used on different drilling rigs and for an automatic data analysis procedure. In this paper, we focused on the automatic detection of drilling cycles, presenting a simple yet reliable system to be universally installed on drilling rigs. The proposed solution covers hardware and software. It is based on the measurement of electric current and acoustic signals. The signal processing methods include threshold-based segmentation, a short-time envelope spectrum and a spectrum for the representation of results. The results of the research have been verified on a real drilling rig within the testing site of its manufacturer by comparing the results with the data of the on-board monitoring system installed on the machine. Novel aspects of our approach include the detection of the pre-boring stage, which has an intermediate amplitude that masks the real drilling cycles, and the use of the percussion instantaneous frequency, which is estimated by acoustic recordings.
Escherichia coli O157:H7 F9 Fimbriae Recognize Plant Xyloglucan and Elicit a Response in Arabidopsis thaliana
Authors: Holmes Ashleigh , Rossez Yannick , Wright Kathryn Mary , Hedley Pete Edward , Morris Jenny , Willats William George Tycho , Holden Nicola Jean
Published: December 2020

Fresh produce is often a source of enterohaemorrhagic Escherichia coli (EHEC) outbreaks. Fimbriae are extracellular structures involved in cell-to-cell attachment and surface colonisation. F9 (Fml) fimbriae have been shown to be expressed at temperatures lower than 37 °C, implying a function beyond the mammalian host. We demonstrate that F9 fimbriae recognize plant cell wall hemicellulose, specifically galactosylated side chains of xyloglucan, using glycan arrays. E. coli expressing F9 fimbriae had a positive advantage for adherence to spinach hemicellulose extract and tissues, which have galactosylated oligosaccharides as recognized by LM24 and LM25 antibodies. As fimbriae are multimeric structures with a molecular pattern, we investigated whether F9 fimbriae could induce a transcriptional response in model plant Arabidopsis thaliana, compared with flagella and another fimbrial type, E. coli common pilus (ECP), using DNA microarrays. F9 induced the differential expression of 435 genes, including genes involved in the plant defence response. The expression of F9 at environmentally relevant temperatures and its recognition of plant xyloglucan adds to the suite of adhesins EHEC has available to exploit the plant niche.
Natural and Synthetic PPARγ Ligands in Tumor Microenvironment: A New Potential Strategy against Breast Cancer
Authors: Augimeri Giuseppina , Gelsomino Luca , Plastina Pierluigi , Giordano Cinzia , Barone Ines , Catalano Stefania , Andò Sebastiano , Bonofiglio Daniela
Published: December 2020

Multiple lines of evidence indicate that activation of the peroxisome proliferator-activated receptor γ (PPARγ) by natural or synthetic ligands exerts tumor suppressive effects in different types of cancer, including breast carcinoma. Over the past decades a new picture of breast cancer as a complex disease consisting of neoplastic epithelial cells and surrounding stroma named the tumor microenvironment (TME) has emerged. Indeed, TME is now recognized as a pivotal element for breast cancer development and progression. Novel strategies targeting both epithelial and stromal components are under development or undergoing clinical trials. In this context, the aim of the present review is to summarize PPARγ activity in breast TME focusing on the role of this receptor on both epithelial/stromal cells and extracellular matrix components of the breast cancer microenvironment. The information provided from the in vitro and in vivo research indicates PPARγ ligands as potential agents with regards to the battle against breast cancer.
Axitinib in Ponatinib-Resistant B-Cell Acute Lymphoblastic Leukemia Harboring a T315L Mutation
Authors: Giudice Valentina , Ghelli Luserna di Rorà Andrea , Serio Bianca , Guariglia Roberto , Giannini Maria Benedetta , Ferrari Anna , Simonetti Giorgia , Selleri Carmine , Martinelli Giovanni
Published: December 2020

Adult acute lymphoblastic leukemia (ALL) with BCR-ABL1 rearrangement (Philadelphia chromosome, Ph) is a hematological aggressive disease with a fatal outcome in more than 50% of cases. Tyrosine kinase inhibitors (TKIs) targeting the activity of BCR-ABL1 protein have improved the prognosis; however, relapses are frequent because of acquired somatic mutations in the BCR-ABL1 kinase domain causing resistance to first, second and third generation TKIs. Axitinib has shown in vitro and ex vivo activity in blocking ABL1; however, clinical trials exploring its efficacy in ALL are missing. Here, we presented a 77-year-old male with a diagnosis of Ph positive ALL resistant to ponatinib and carrying a rare threonine to leucine (T315L) mutation on BCR-ABL1 gene. The patient was treated with axitinib at 5 mg/twice daily as salvage therapy showing an immediate although transient benefit with an overall survival of 9.3 months. Further dose-finding and randomized clinical trials are required to assess the real efficacy of axitinib for adult Ph positive ALL resistant to third generation TKIs.
Antioxidant Activity of Hydrogen Water Mask Pack Composed of Gel-Type Emulsion and Hydrogen Generation Powder
Authors: Kwon Hye-Jin , Han Sang-Beom , Park Kyung-Won
Published: December 2020

In this study, hydrogen generation powder samples were prepared using zinc carbonate as a precursor, at a temperature varying from 400 to 700 °C in H2 atmosphere, and were characterized in terms of antioxidant activity. The concentration of dissolved hydrogen obtained by the powder samples was measured using a dissolved hydrogen meter as a function of time. In addition, the antioxidant activity of the samples was evaluated based on the Oyaizu’s method, removal rate of ·OH radicals, and ferric reducing antioxidant power. Finally, the hydrogen mask pack was fabricated using the hydrogen generation powder sample and gel-type emulsion. In the clinical test on the mask pack, the effect of the mask on skin aging was characterized and compared to that of a commercial sample. The skin densities of the participants in the experimental group and the control group increased by 18.41% and 9.93% after 4 weeks, respectively. The improved skin density of the participants who used the hydrogen mask pack in the experimental group, might be attributed to the recovery effect of the hydrogen molecule in the mask pack on the denatured thick skin layer.