bluuebunny/crossref_metadata_2025 huggingface dataset:
First-In-Class CD13-Targeted Tissue Factor tTF-NGR in Patients with Recurrent or Refractory Malignant Tumors: Results of a Phase I Dose-Escalation Study
Authors: Schliemann Christoph , Gerwing Mirjam , Heinzow Hauke , Harrach Saliha , Schwöppe Christian , Wildgruber Moritz , Hansmeier Anna A. , Angenendt Linus , Berdel Andrew F. , Stalmann Ursula , Berning Björna , Kratz-Albers Karsten , Middelberg-Bisping Kristina , Wiebe Stefanie , Albring Jörn , Wilms Christian , Hartmann Wolfgang , Wardelmann Eva , Krähling Tobias , Heindel Walter , Gerss Joachim , Bormann Eike , Schmidt Hartmut , Lenz Georg , Kessler Torsten , Mesters Rolf M. , Berdel Wolfgang E.
Published: June 2020

Background: Aminopeptidase N (CD13) is present on tumor vasculature cells and some tumor cells. Truncated tissue factor (tTF) with a C-terminal NGR-peptide (tTF-NGR) binds to CD13 and causes tumor vascular thrombosis with infarction. Methods: We treated 17 patients with advanced cancer beyond standard therapies in a phase I study with tTF-NGR (1-h infusion, central venous access, 5 consecutive days, and rest periods of 2 weeks). The study allowed intraindividual dose escalations between cycles and established Maximum Tolerated Dose (MTD) and Dose-Limiting Toxicity (DLT) by verification cohorts. Results: MTD was 3 mg/m2 tTF-NGR/day × 5, q day 22. DLT was an isolated and reversible elevation of high sensitivity (hs) Troponin T hs without clinical sequelae. Three thromboembolic events (grade 2), tTF-NGR-related besides other relevant risk factors, were reversible upon anticoagulation. Imaging by contrast-enhanced ultrasound (CEUS) and dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) showed major tumor-specific reduction of blood flow in all measurable lesions as proof of principle for the mode of action of tTF-NGR. There were no responses as defined by Response Evaluation Criteria in Solid Tumors (RECIST), although some lesions showed intratumoral hemorrhage and necrosis after tTF-NGR application. Pharmacokinetic analysis showed a t1/2(terminal) of 8 to 9 h without accumulation in daily administrations. Conclusion: tTF-NGR is safely applicable with this regimen. Imaging showed selective reduction of tumor blood flow and intratumoral hemorrhage and necrosis.
c-Src and EGFR Inhibition in Molecular Cancer Therapy: What Else Can We Improve?
Authors: Belli Stefania , Esposito Daniela , Servetto Alberto , Pesapane Ada , Formisano Luigi , Bianco Roberto
Published: June 2020

The proto-oncogene c-Src is a non-receptor tyrosine kinase playing a key role in many cellular pathways, including cell survival, migration and proliferation. c-Src de-regulation has been observed in several cancer types, making it an appealing target for drug discovery efforts. Recent evidence emphasizes its crucial role not only in promoting oncogenic traits, but also in the acquisition and maintenance of cancer resistance to various chemotherapeutic or molecular target drugs. c-Src modulates epidermal growth factor receptor (EGFR) activation and amplifies its downstream oncogenic signals. In this review, we report several studies supporting c-Src kinase role in the intricate mechanisms of resistance to EGFR tyrosine kinase inhibitors (TKIs). We further highlighted pre- and clinical progresses of combined treatment strategies made in recent years. Several pre-clinical data have encouraged the use of c-Src inhibitors in combination with EGFR inhibitors. However, clinical trials provided controversial outcomes in some cancer types. Despite c-Src inhibitors showed good tolerability in cancer patients, no incontrovertible and consistent clinical responses were recorded, supporting the idea that a better selection of patients is needed to improve clinical outcome. Currently, the identification of biological markers predictive of therapy response and the accurate molecular screening of cancer patients aimed to gain most clinical benefits become decisive and mandatory.
Prognostic Significance of CHIP and RIPK3 in Non-Small Cell Lung Cancer
Authors: Kim Jisup , Chung Joon-Yong , Park Young Soo , Jang Se Jin , Kim Hyeong Ryul , Choi Chang-Min , Song Joon Seon
Published: June 2020

RIPK3 is a key regulator of necroptosis, which plays a double-edged sword role in tumor progression. CHIP is an E3 ubiquitin ligase that regulates necroptosis by degrading RIPK3. Here, we investigated the prognostic value of RIPK3 and CHIP expression in 404 patients with non-small cell lung cancer (NSCLC). Expressions of CHIP and RIPK3 showed opposite correlations with survival. CHIP expression was associated with the longer overall survival (OS), whereas RIPK3 expression was associated with the shorter OS. RIPK3 positivity showed marginal association with shorter OS and disease-free survival (DFS) in adjuvant radiotherapy recipients but not in non-recipients, suggesting that necroptosis may induce radioresistance. In multivariate analysis, CHIP expression was associated with longer OS. Compared with other patients, CHIP(−)/RIPK3(+) patients had shorter OS and DFS. In summary, in patients with NSCLC, the expression of CHIP was an independent favorable prognostic factor while that of RIPK3 was an adverse prognostic factor.
Combined PARP Inhibition and Immune Checkpoint Therapy in Solid Tumors
Authors: Peyraud Florent , Italiano Antoine
Published: June 2020

Genomic instability is a hallmark of cancer related to DNA damage response (DDR) deficiencies, offering vulnerabilities for targeted treatment. Poly (ADP-ribose) polymerase (PARP) inhibitors (PARPi) interfere with the efficient repair of DNA damage, particularly in tumors with existing defects in DNA repair, and induce synthetic lethality. PARPi are active across a range of tumor types harboring BRCA mutations and also BRCA-negative cancers, such as ovarian, breast or prostate cancers with homologous recombination deficiencies (HRD). Depending on immune contexture, immune checkpoint inhibitors (ICIs), such as anti-PD1/PD-L1 and anti-CTLA-4, elicit potent antitumor effects and have been approved in various cancers types. Although major breakthroughs have been performed with either PARPi or ICIs alone in multiple cancers, primary or acquired resistance often leads to tumor escape. PARPi-mediated unrepaired DNA damages modulate the tumor immune microenvironment by a range of molecular and cellular mechanisms, such as increasing genomic instability, immune pathway activation, and PD-L1 expression on cancer cells, which might promote responsiveness to ICIs. In this context, PARPi and ICIs represent a rational combination. In this review, we summarize the basic and translational biology supporting the combined strategy. We also detail preclinical results and early data of ongoing clinical trials indicating the synergistic effect of PARPi and ICIs. Moreover, we discuss the limitations and the future direction of the combination.
Identifying and Overcoming Mechanisms of PARP Inhibitor Resistance in Homologous Recombination Repair-Deficient and Repair-Proficient High Grade Serous Ovarian Cancer Cells
Authors: Gomez Miriam K. , Illuzzi Giuditta , Colomer Carlota , Churchman Michael , Hollis Robert L. , O’Connor Mark J. , Gourley Charlie , Leo Elisabetta , Melton David W.
Published: June 2020

High grade serous ovarian cancer (HGSOC) is a major cause of female cancer mortality. The approval of poly (ADP-ribose) polymerase (PARP) inhibitors for clinical use has greatly improved treatment options for patients with homologous recombination repair (HRR)-deficient HGSOC, although the development of PARP inhibitor resistance in some patients is revealing limitations to outcome. A proportion of patients with HRR-proficient cancers also benefit from PARP inhibitor therapy. Our aim is to compare mechanisms of resistance to the PARP inhibitor olaparib in these two main molecular categories of HGSOC and investigate a way to overcome resistance that we considered particularly suited to a cancer like HGSOC, where there is a very high incidence of TP53 gene mutation, making HGSOC cells heavily reliant on the G2 checkpoint for repair of DNA damage and survival. We identified alterations in multiple factors involved in resistance to PARP inhibition in both HRR-proficient and -deficient cancers. The most frequent change was a major reduction in levels of poly (ADP-ribose) glycohydrolase (PARG), which would be expected to preserve a residual PARP1-initiated DNA damage response to DNA single-strand breaks. Other changes seen would be expected to boost levels of HRR of DNA double-strand breaks. Growth of all olaparib-resistant clones isolated could be controlled by WEE1 kinase inhibitor AZD1775, which inactivates the G2 checkpoint. Our work suggests that use of the WEE1 kinase inhibitor could be a realistic therapeutic option for patients that develop resistance to olaparib.
The Biodiversity of Water Mites That Prey on and Parasitize Mosquitoes
Authors: Vasquez Adrian A. , Kabalan Bana A. , Ram Jeffrey L. , Miller Carol J.
Published: June 2020

Water mites form one of the most biodiverse groups within the aquatic arachnid class. These freshwater macroinvertebrates are predators and parasites of the equally diverse nematocerous Dipterans, such as mosquitoes, and water mites are believed to have diversified as a result of these predatory and parasitic relationships. Through these two major biotic interactions, water mites have been found to greatly impact a variety of mosquito species. Although these predatory and parasitic interactions are important in aquatic ecology, very little is known about the diversity of water mites that interact with mosquitoes. In this paper, we review and update the past literature on the predatory and parasitic mite–mosquito relationships, update past records, discuss the biogeographic range of these interactions, and add our own recent findings on this topic conducted in habitats around the Laurentian Great Lakes. The possible impact on human health, along with the importance of water mite predator–prey dynamics in aquatic food webs, motivates an increase in future research on this aquatic predator and parasite and may reveal novel ecological functions that these parasitic and predator–prey relationships mediate.
LSSVR Model of G-L Mixed Noise-Characteristic with Its Applications
Authors: Zhang Shiguang , Zhou Ting , Sun Lin , Wang Wei , Chang Baofang
Published: June 2020

Due to the complexity of wind speed, it has been reported that mixed-noise models, constituted by multiple noise distributions, perform better than single-noise models. However, most existing regression models suppose that the noise distribution is single. Therefore, we study the Least square S V R of the Gaussian–Laplacian mixed homoscedastic ( G L M − L S S V R ) and heteroscedastic noise ( G L M H − L S S V R ) for complicated or unknown noise distributions. The ALM technique is used to solve model G L M − L S S V R . G L M − L S S V R is used to predict short-term wind speed with historical data. The prediction results indicate that the presented model is superior to the single-noise model, and has fine performance.
Time-Adaptive Statistical Test for Random Number Generators
Authors: Ryabko Boris
Published: June 2020

The problem of constructing effective statistical tests for random number generators (RNG) is considered. Currently, there are hundreds of RNG statistical tests that are often combined into so-called batteries, each containing from a dozen to more than one hundred tests. When a battery test is used, it is applied to a sequence generated by the RNG, and the calculation time is determined by the length of the sequence and the number of tests. Generally speaking, the longer is the sequence, the smaller are the deviations from randomness that can be found by a specific test. Thus, when a battery is applied, on the one hand, the “better” are the tests in the battery, the more chances there are to reject a “bad” RNG. On the other hand, the larger is the battery, the less time it can spend on each test and, therefore, the shorter is the test sequence. In turn, this reduces the ability to find small deviations from randomness. To reduce this trade-off, we propose an adaptive way to use batteries (and other sets) of tests, which requires less time but, in a certain sense, preserves the power of the original battery. We call this method time-adaptive battery of tests. The suggested method is based on the theorem which describes asymptotic properties of the so-called p-values of tests. Namely, the theorem claims that, if the RNG can be modeled by a stationary ergodic source, the value − l o g π ( x 1 x 2 … x n ) / n goes to 1 − h when n grows, where x 1 x 2 … is the sequence, π ( ) is the p-value of the most powerful test, and h is the limit Shannon entropy of the source.
Long-Range Dependence in Financial Markets: A Moving Average Cluster Entropy Approach
Authors: Murialdo Pietro , Ponta Linda , Carbone Anna
Published: June 2020

A perspective is taken on the intangible complexity of economic and social systems by investigating the dynamical processes producing, storing and transmitting information in financial time series. An extensive analysis based on the moving average cluster entropy approach has evidenced market and horizon dependence in highest-frequency data of real world financial assets. The behavior is scrutinized by applying the moving average cluster entropy approach to long-range correlated stochastic processes as the Autoregressive Fractionally Integrated Moving Average (ARFIMA) and Fractional Brownian motion (FBM). An extensive set of series is generated with a broad range of values of the Hurst exponent H and of the autoregressive, differencing and moving average parameters p , d , q . A systematic relation between moving average cluster entropy and long-range correlation parameters H, d is observed. This study shows that the characteristic behaviour exhibited by the horizon dependence of the cluster entropy is related to long-range positive correlation in financial markets. Specifically, long range positively correlated ARFIMA processes with differencing parameter d ≃ 0.05 , d ≃ 0.15 and d ≃ 0.25 are consistent with moving average cluster entropy results obtained in time series of DJIA, S&P500 and NASDAQ. The findings clearly point to a variability of price returns, consistently with a price dynamics involving multiple temporal scales and, thus, short- and long-run volatility components. An important aspect of the proposed approach is the ability to capture detailed horizon dependence over relatively short horizons (one to twelve months) and thus its relevance to define risk analysis indices.
From the Jordan Product to Riemannian Geometries on Classical and Quantum States
Authors: Ciaglia Florio M. , Jost Jürgen , Schwachhöfer Lorenz
Published: June 2020

The Jordan product on the self-adjoint part of a finite-dimensional C * -algebra A is shown to give rise to Riemannian metric tensors on suitable manifolds of states on A , and the covariant derivative, the geodesics, the Riemann tensor, and the sectional curvature of all these metric tensors are explicitly computed. In particular, it is proved that the Fisher–Rao metric tensor is recovered in the Abelian case, that the Fubini–Study metric tensor is recovered when we consider pure states on the algebra B ( H ) of linear operators on a finite-dimensional Hilbert space H , and that the Bures–Helstrom metric tensors is recovered when we consider faithful states on B ( H ) . Moreover, an alternative derivation of these Riemannian metric tensors in terms of the GNS construction associated to a state is presented. In the case of pure and faithful states on B ( H ) , this alternative geometrical description clarifies the analogy between the Fubini–Study and the Bures–Helstrom metric tensor.
Impact of Different Regulatory Structures on the Management of Energy Communities
Authors: de la Hoz Jordi , Alonso Àlex , Coronas Sergio , Martín Helena , Matas José
Published: June 2020

The following paper aims to prove the importance of embedding the regulatory framework when analyzing the distributed generation activity of an energy community. At present, most of the scientific literature has focused on distributed energy, and energy communities address the issue of regulatory frameworks qualitatively. In this paper, the most representative regulatory frameworks devoted to the promotion of energy communities were analyzed and synthesized, namely, feed-in tariffs, net metering, and the self-consumption scheme. As a result, an algebraic model able to represent the essence of the regulatory structures related to those remuneration mechanisms was obtained. Next, this model was embedded into a physical model, based on real data, previously created. The resulting Mixed Integer Linear Program (MILP) was used to identify the implications of these frameworks. The results demonstrate the impact of regulatory schemes on energy management and economic results of an energy community. Indeed, profitability changes drastically depending on which remuneration scheme is applied to an energy community.
Water-Energy Management for Demand Charges and Energy Cost Optimization of a Pumping Stations System under a Renewable Virtual Power Plant Model
Authors: Naval Natalia , Yusta Jose M.
Published: June 2020

The effects of climate change seriously affect agriculture at different latitudes of the planet because periods of drought are intensifying and the availability of water for agricultural irrigation is reducing. In addition, the energy cost associated with pumping water has increased notably in recent years due to, among other reasons, the maximum demand charges that are applied annually according to the contracted demand in each facility. Therefore, very efficient management of both water resources and energy resources is required. This article proposes the integration of water-energy management in a virtual power plant (VPP) model for the optimization of energy costs and maximum demand charges. For the development of the model, a problem related to the optimal operation of electricity generation and demand resources arises, which is formulated as a nonlinear mixed-integer programming model (MINLP). The objective is to maximize the annual operating profit of the VPP. It is worth mentioning that the model is applied to a large irrigation system using real data on consumption and power generation, exclusively renewable. In addition, different scenarios are analyzed to evaluate the variability of the operating profit of the VPP with and without intraday demand management as well as the influence of the wholesale electricity market price on the model. In view of the results obtained, the model that integrates the management of the water-energy binomial increases the self-consumption of renewable energy and saves electricity supply costs.
Distributed FACTS for Power System Transient Stability Control
Authors: Bruno Sergio , De Carne Giovanni , La Scala Massimo
Published: June 2020

The high penetration of renewable energy sources, combined with a limited possibility to expand the transmission infrastructure, stretches the system stability in the case of faults. For this reason, operators are calling for additional control flexibility in the grid. In this paper, we propose the deployment of switchable reactors and capacitors distributed on the grid as a control resource for securing operations during severe contingencies and avoiding potential blackouts. According to the operating principles, the line reactance varies by switching on or off a certain number of distributed series reactors and capacitors and, therefore, the stabilizing control rule is based on a stepwise time-discrete control action. A control strategy, based on dynamic optimization, is proposed and tested on a realistic-sized transmission system.
Research on Real-Time Optimized Operation and Dispatching Strategy for Integrated Energy System Based on Error Correction
Authors: Zeng Aidong , Hao Sipeng , Ning Jia , Xu Qingshan , Jiang Ling
Published: June 2020

A real-time error correction operation model for an integrated energy system is proposed in this paper, based on the analysis of the real-time optimized operation structure of an integrated energy system and the characteristics of the system. The model makes real-time corrections to the day-ahead operation strategy of the integrated energy system, to offset forecast errors from the renewable power generation system and multi-energy load system. When unbalanced power occurs in the system due to prediction errors, the model comprehensively considers the total capacity of each energy supply and energy storage equipment, adjustable margin, power climbing speed and adjustment cost, to formulate the droop rate which determines the unbalanced power that each device will undertake at the next time interval, while taking the day-ahead dispatching goals of the system into consideration. The case study shows that the dispatching strategy obtained by the real-time error correction operation model makes the power output change trend of the energy supply equipment consistent with the day-ahead dispatching plan at the next time interval, which ensures the safety, stability and economy of the real-time operation of the integrated energy system.
Assessment of Colorimetric Parameters for HPS Lamp with Electromagnetic Control Gear and Electronic Ballast
Authors: Sikora Roman , Markiewicz Przemysław
Published: June 2020

Road lighting is an important element of road infrastructure influencing on the road safety. It helps road users to identify potential hazards on the road and reduces the risk of a road accident. Improving the energy efficacy of road lighting installations requires using new technologies. Currently, high-pressure sodium (HPS) lamps are still most commonly used in road lighting. Many of the luminaires with HPS lamps are still in good technical condition and there is no economic justification for replacing them (except improving energy efficacy). One of the methods of improving their energy efficacy is to replace the electromagnetic control gear (ECG) with an electronic ballast (EB). This replacement may affect the colorimetric parameters of the HPS lamps. Two methods to the estimation change of colorimetric parameters after the replacement of ECG to EB were used. The first is CIE TN 001:2014 and the second is ANSI/IES TM-30-15. The article also presents the advantages and disadvantages of these methods in relation to the evaluation of changes in colorimetric parameters of HPS lamps after the replacement of the ECG with an EB. After the replacement of ECG to EB, the smallest reduction of Ra (colour rendering index) occurred for the 150 W lamp by 31.30% and the highest reduction for the 70 W lamp by 65.52%. Considering the changes of the fidelity indicator Rf and gamut indicator Rg, their changes are significantly smaller than for Ra. The smallest change of Rf value was observed for a 150 W lamp (6.00%) and the largest for a 70 W lamp by 25.00%. In case of Rg, similar changes were observed—for 150 W lamp by 9.26% and for 70 W lamp by 21.88%. The ANSI/IES TM-30-15 method is more suitable for evaluating colorimetric parameters after replacing ECG with EB. Using only Ra to evaluate changes of HPS lamps colorimetric parameters after replacing the ballast type can lead to incorrect conclusions concerning changes of colorimetric parameters. Based on the ANSI/IES TM-30-15 method, it has been proposed to introduce the Δf,g indicator which determines the change of colorimetric parameters based on fidelity and gamut colour indicator.
Replacement Reserve for the Italian Power System and Electricity Market
Authors: Caprabianca Mauro , Falvo Maria Carmen , Papi Lorenzo , Promutico Lucrezia , Rossetti Viviana , Quaglia Federico
Published: June 2020

Over the last years, power systems around the globe experienced deep changes in their operation, mainly induced by the widespread of Intermittent Renewable Energy Sources (IRES). These changes involved a review of market and operational rules, in the direction of a stronger integration. At European level, this integration is in progress, driven by the new European guidelines and network codes, which deal with multiple issues, from market design to operational security. In this framework, the project TERRE (Trans European Replacement Reserve Exchange) is aimed at the realization of a European central platform, called LIBRA, for the exchange of balancing resources and, in particular, for the activation of the procured Replacement Reserve (RR) resources. The Italian Transmission System Operator (TSO), TERNA, is a participant of the project and it is testing new methodologies for the sizing of RR and its required activation throughout the TERRE process. The aim of the new methodologies is to find areas of potential improvement in the sizing of RR requirements and activation, which open up the possibility for a reduction of the procurement cost, without endangering the security of the power system. This paper describes a new RR sizing methodology, proposed by TERNA, which is based on a persistence method, showing its results on real data and highlighting key advantages and potential limitations of this approach. In order to overcome these limitations, a literature review on alternative approaches has been carried out, identifying nowcasting techniques as a relevant alternative for the very short term forecast horizon. These one could be further investigated and tested in the future, using the proposed persistence method as a benchmark.
Economic Analysis of Integrated Ground Source Heat Pumps on a Shared Ground Loop
Authors: Shin Jeong Soo , Kim Sean Hay , Park Jong Woo
Published: June 2020

An integrated geothermal system in which heat pumps for air conditioning and hot water both share the same ground loop was proposed in our previous study. Although this system produced electricity savings of 15% compared to a conventional system in which the two heat pumps operated on their own ground loop, practical requirements regarding further lowering the operation cost of the integrated geothermal system and the possibility of the energy savings being low during winter initiated further investigation into potential energy conservation measures at no initial cost increase, if possible. Outdoor reset control for hot water supply and sequential heat pump operation, both of which could be included at no extra cost, were subsequently targeted as potential measures for greater electricity savings and economic feasibility. When these measures were incorporated into the integrated geothermal system, electricity savings of approximately 25% during the heating season compared to the conventional system were predicted. Eventually it led to annual electricity savings of about 25% compared to the conventional system, which is up to 9.6 million South Korean won a year at today’s rates. Additionally, it reached the break-even point earlier than one year after installation.
Classification of Three-Phase Grid-Tied Microinverters in Photovoltaic Applications
Authors: Shawky Ahmed , Ahmed Mahrous , Orabi Mohamed , Aroudi Abdelali El
Published: June 2020

Microinverters are an essential part of the photovoltaic (PV) industry with significant exponential prevalence in new PV module architectures. However, electrolyte capacitors used to decouple double line frequency make the single-phase microinverters topologies the slightest unit in this promising industry. Three-phase microinverter topologies are the new trend in this industry because they do not have double-line frequency problems and they do not need the use of electrolyte capacitors. Moreover, these topologies can provide additional features such as four-wire operation. This paper presents a detailed discussion of the strong points of three-phase microinverters compared to single-phase counterparts. The developed topologies of three-phase microinverters are presented and evaluated based on a new classification based on the simplest topologies among dozens of existing inverters. Moreover, the paper considers the required standardized features of PV, grid, and the microinverter topology. These features have been classified as mandatory and essential. Examples of the considered features for classifications are Distributed Maximum Power Point Tracking (DMPPT), voltage boosting gain, and four-wire operation. The developed classification is used to identify the merits and demerits of the classified inverter topologies. Finally, a recommendation is given based on the classified features, chosen inverter topologies, and associated features.
Modeling and Control of Supercritical and Ultra-Supercritical Power Plants: A Review
Authors: Mohamed Omar , Khalil Ashraf , Wang Jihong
Published: June 2020

This paper presents a critical review of the research conducted for modeling and controlling supercritical power plants. Thermal power plants are classified according to the boiler pressure to supercritical and subcritical. The modeling concepts and control strategies of supercritical generation units are far more complex than those of subcritical. On the other hand, supercritical generation technologies are more efficient and much cleaner than subcritical generation units. From a deep technical analysis of the literature, there is no review that is dedicated to models-based control of supercritical power plants and most previous reviews are found to be too general to modeling-based control of fossil fuelled energy sources. This review reports the advancements on modeling and control of supercritical and ultra-supercritical plants as cleaner generation technologies. The various published achievements for modeling supercritical and ultra-supercritical units have been reviewed. The control strategies that fulfill the practical load demand requirements while keeping optimum efficiencies are also reviewed. Finally, expected future directions are reported as recommendations to overcome future challenges. The paper can be used as a brief educational directory to the postgraduate students or future researchers in the field.
Pellet Production from Woody and Non-Woody Feedstocks: A Review on Biomass Quality Evaluation
Authors: Picchio Rodolfo , Latterini Francesco , Venanzi Rachele , Stefanoni Walter , Suardi Alessandro , Tocci Damiano , Pari Luigi
Published: June 2020

Forest and agricultural biomass are important sources of renewable and sustainable fuel for energy production. Their increasing consumption is mainly related to the increase in global energy demand and fossil fuel prices but also to the limited availability of petroleum and the lower environmental impact of these biomass compared with other non-renewable fuels. In particular, the pellet sector has seen important developments in terms of both production and the number of installed transformation plants. In addition, pellet production from non-woody biomass is increasing in importance. One of the fundamental aspects for the correct and sustainable use of a biofuel is evaluation of its quality. This is even more important when dealing with pellet production, considering the broad spectrum of possible raw materials for pelletizing. Considering the significant number of papers dealing with pellet quality evaluation and improvement in the last decade, this review aims to give the reader an overall view of the most current knowledge about this large and interesting topic. We focused on pellets of agricultural and forestry origin and analyzed papers regarding the specific topic of pellet quality evaluation and improvement from the last five years (2016–2020). In particular, the review findings are presented in the following order: the influence of different agro-forest management systems on pellet quality; analysis of pellets from pure feedstocks (no blending or binders); the influence of blending and binders on pellet quality; and the influence of pre and post treatments. Finally, a brief discussion about actual research lacks in this topic and the possibilities for future research are presented. It is important to underline that the present review is focused on the influence of the biomass characteristics on pellet quality. The effects of the process parameters (die temperature, applied pressure, holding time) on pellet features are not considered in this review, because that is another very large topic deserving a dedicated paper.
A Study on Electric Vehicles Participating in the Load Regulation of Urban Complexes
Authors: Xu Qiwei , Huang Jianshu , Han Yue , Yang Yun , Luo Lingyan
Published: June 2020

Urban complex (UC) is the main place of citizens’ life and work. The construction of an UC often needs to expand the capacity of the power equipment. This paper proposes to use electric vehicles (EVs) in an UC to reduce the power load of the UC during peak periods, so that lower capacity power equipment can be used to reduce the construction costs of the UC and the transformation of electrical facilities. In order to find the relationship between parking and power load in the UC, the UC is decomposed into different functional areas for research. Then, we build a parking information database for clustering and calculation. Divide the load peak into adjustment intervals of equal duration. The EVs parked in the UC for each regulation interval (RI) are grouped according to parking characteristics. Establish an objective function with the minimum load variance during peak hours. The discharge capacity of each group in each RI is obtained and distributed to each EV to realize peak load reduction of UC. Finally, the results of case analysis show that the strategy can reduce the peak load effectively thus save the cost of UC construction.
Porous Cores in Small Thermoacoustic Devices for Building Applications
Authors: Auriemma Fabio , Di Giulio Elio , Napolitano Marialuisa , Dragonetti Raffaele
Published: June 2020

The thermoacoustic behavior of different typologies of porous cores is studied in this paper with the goal of finding the most suitable solution for small thermoacoustic devices, including solar driven air coolers and generators, which can be used in future buildings. Cores provided with circular pores, with rectangular slits and with arrays of parallel cylindrical pins are investigated. For the type of applications in focus, the main design constraints are represented by the reduced amount of the input heat power and the size limitations of the device. In this paper, a numerical procedure has been implemented to assess the behavior of the different core typologies. For a fixed input heat power, the maximum acoustic power delivered by each core is computed and the corresponding engine configuration (length of the resonator and position of the core) is provided. It has been found that cores with parallel pins provide the largest amount of acoustic power with the smallest resonator length. This conclusion has been confirmed by experiments where additive manufactured cores have been tested in a small, light-driven, thermoacoustic prime mover.
Energy and Exergy Analysis of Using Turbulator in a Parabolic Trough Solar Collector Filled with Mesoporous Silica Modified with Copper Nanoparticles Hybrid Nanofluid
Authors: Rostami Sara , Shahsavar Amin , Kefayati Gholamreza , Shahsavar Goldanlou Aysan
Published: June 2020

Designing the most efficient parabolic trough solar collector (PTSC) is still a demanding and challenging research area in solar energy systems. Two effective recommended methods for this purpose that increase the thermal characteristics of PTSCs are adding turbulators and nanofluids. To study the effects of the two approaches on the energy efficiency of PTSCs, a stainless steel turbulator was used and solid nanoparticles of Cu/SBA-15 were added to the water with the volume concentrations of 0.019% to 0.075%. The generated turbulence in the fluid flow was modeled by the SST k–ω turbulent model. The results in daylight demonstrated that energy efficiency increases steadily by 11:30 a.m., and then, starts to drop gradually due to more irradiations at noon. It was observed that applying the turbulator to the studied PTSC has a significant influence on the enhancement of energy efficiency. Adding the nanoparticles augmented the average Nusselt number inside the solar collector in various studied Reynolds numbers. It was also found that the increase in volume concentrations of nanoparticles enhances heat transfer regularly.
Influence of the Carrier Selective Front Contact Layer and Defect State of a-Si:H/c-Si Interface on the Rear Emitter Silicon Heterojunction Solar Cells
Authors: Lee Sunhwa , Pham Duy Phong , Kim Youngkuk , Cho Eun-Chel , Park Jinjoo , Yi Junsin
Published: June 2020

In this research, simulations were performed to investigate the effects of carrier selective front contact (CSFC) layer and defect state of hydrogenated amorphous silicon passivation layer/n-type crystalline silicon interface in silicon heterojunction (SHJ) solar cells employing the Automat for Simulation of hetero-structure (AFORS-HET) simulation program. The results demonstrated the effects of band offset determined by band bending at the interface of the CSFC layer/passivation layer. In addition, the nc-SiOx: H CSFC layer not only reduces parasitic absorption loss but also has a tunneling effect and field effect passivation. Furthermore, it increased the selectivity of contact. In the experimental cell, nc-SiOx:H was used as the CSFC layer, where efficiency of the SHJ solar cell was 22.77%. Our investigation shows that if a SiOx layer passivation layer is used, the device can achieve efficiency up to 25.26%. This improvement in the cell is mainly due to the enhancement in open circuit voltage (Voc) because of lower interface defect density resulting from the SiOx passivation layer.
Predictive Direct Power Control for Dual-Active-Bridge Multilevel Inverter Based on Conservative Power Theory
Authors: Bohari Azuwien Aida , Goh Hui Hwang , Tonni Agustiono Kurniawan , Lee Sze Sing , Sim Sy Yi , Goh Kai Chen , Lim Chee Shen , Luo Yi Chen
Published: June 2020

This paper explores the feasibility of multilevel dual-active bridge-inverter (DABMI) applications for grid-connected applications of a modern Model of Predictive Direct Power Control (MPDPC) based on the conservative power theory (CPT). In the case of unbalanced grid voltages, the objective of the study is to promote continued active and reactive energy in MPDPC without reducing efficiency such as transient response and current harmonics. The nature of the instantaneous p-q theory permits only one out of three control targets to be fulfilled. The proposed control approached directly regulates the instantaneous active and reactive power to achieve three particular control objectives namely sinusoidal and symmetrical grid current, cancelling twice of fundamental grid frequency reactive power ripples, and removing twice grid frequency active power ripple. The techniques of complicated Grid part sequence extraction are unnecessary and improved at no extra expense, as is the case with current MPDPC fault-tolerant approaches. The instantaneous power at the next sampling instant is predicted with the newly developed discrete-time model. Each possible switching state will then be evaluated in the cost function defined until the optimal state which lead to the minimum power errors is determined. In MATLAB/Simulink simulation, the proposed CPT-based MPDPC measures reliability and performance at balanced and unbalanced grid voltages then compared with the conventional and existing MPDPC The proposed method manages to achieve all of three control targets which generates sinusoidal grid currents and attenuates active and reactive power ripple of twice the grid frequency exactly at the same time without losing its critical efficiency including transient reaction and current harmonics.
Administration of Very Low Doses of Estradiol Modulates the LH Response to a GnRH Bolus and the LH and Cortisol Responses to Naloxone Infusion in Patients with Functional Hypothalamic Amenorrhea (FHA): A Pilot Study
Authors: Genazzani Alessandro D. , Despini Giulia , Prati Alessia , Manzo Alba , Petrillo Tabatha , Tomatis Veronica , Giannini Andrea , Simoncini Tommaso
Published: June 2020

Background: Functional Hypothalamic Amenorrhea (FHA) is a stress-induced blockade of the reproductive axis. Such impairment is mainly due to altered control of GnRH-induced gonadotropin secretion as well as alterations of other endocrine functions. Methods: Seventeen patients with FHA participated in the study. Basal hormonal profiles and GnRH and Naloxone tests for LH (Luteinizing Hormone) and for LH and cortisol responses, respectively, were performed before and after two weeks of administration of a very low dose of estradiol (2.5 ng two times a day). Results: The treatment improved both gonadotropins, mainly LH. The LH response to the GnRH test improved in terms of the peak amplitude, as evaluated using Instantaneous Secretory Rates (ISR) computation. Moreover, when performing the Naloxone test after the treatment interval, FHA patients showed a quicker LH response and recovery of the cortisol response. Conclusions: Our study supports the relevance of very low dose estradiol priming to promote and restore impaired neuroendocrine function in patients with FHA.
Natural Weathering of Bio-Based Façade Materials
Authors: Alao Percy , Visnapuu Kevin , Kallakas Heikko , Poltimäe Triinu , Kers Jaan
Published: June 2020

Although there is a global awareness that the exploitation of non-renewable materials is unsustainable, there has been limited interest in fully utilizing natural, renewable resources like wood and its products because of the service durability concerns. One such issue is the aesthetical degradation of wooden facades due to the impact of weathering. This research was carried out as an international cooperation project to ascertain the weathering resistance of bio-based façade materials under the Estonian climate. In total, 120 bio-based façade materials obtained from 31 different companies, universities and research institutions from 17 countries were investigated. The specimens were placed on an exposure rack, inclined at an angle of 45° located at 59°23′50.6″ N 24°39′24.0″ E and then subjected to accelerated natural weathering for 2 years. Parameters such as precipitation, UV index, temperature and relative humidity were measured during the period of the natural weathering. The influence of the weathering on the colour change and cracks on the surface of test specimens was evaluated using Minolta Chroma Meter CR-121 (Konica Minolta INC., Tokyo, Japan) and Avongard Check Width Gauge (Avongard Ltd., Gloucestershire, UK), respectively. The results showed that the untreated natural wood façade materials presented the least resistance to weathering, while 63 of the tested materials developed checks. The outcome of this study is essential to the optimization of software-simulating changes in the appearance of façade materials in outdoor conditions.
Organic Carbon Storage and 14C Apparent Age of Upland and Riparian Soils in a Montane Subtropical Moist Forest of Southwestern China
Authors: Liu Xianbin , Zou Xiaoming , Cao Min , Luo Tushou
Published: June 2020

Upland and riparian soils usually differ in soil texture and moisture conditions, thus, likely varying in carbon storage and turnover time. However, few studies have differentiated their functions on the storage of soil organic carbon (SOC) in sub-tropical broad-leaved evergreen forests. In this study, we aim to uncover the SOC storage and 14C apparent age, in the upland and riparian soils of a primary evergreen broad-leaved montane subtropical moist forest in the Ailao Mountains of southwestern China. We sampled the upland and riparian soils along four soil profiles down to the parent material at regular intervals from two local representative watersheds, and determined SOC concentrations, δ13C values and 14C apparent ages. We found that SOC concentration decreased exponentially and 14C apparent age increased linearly with soil depth in the four soil profiles. Although, soil depth was deeper in the upland soil profiles than the riparian soil profiles, the weighted mean SOC concentration was significantly greater in the riparian soil (25.7 ± 3.9 g/kg) than the upland soil (19.7 ± 2.3 g/kg), but has an equal total SOC content per unit of ground area around 21 kg/m2 in the two different type soils. SOC δ13C values varied between −23.7 (±0.8)‰ and −33.2 (±0.2)‰ in the two upland soil profiles and between −25.5 (±0.4)‰ and −36.8 (±0.4)‰ along the two riparian soil profiles, with greater variation in the riparian soil profiles than the upland soil profiles. The slope of increase in SOC 14C apparent age along soil depth in the riparian soil profiles was greater than in the upland soil profiles. The oldest apparent age of SOC 14C was 23,260 (±230) years BP (before present, i.e., 1950) in the riparian soil profiles and 19,045 (±150) years BP in the upland soil profiles. Our data suggest that the decomposition of SOC is slower in the riparian soil than in the upland soil, and the increased SOC loss in the upland soil from deforestation may partially be compensated by the deposition of the eroded upland SOC in the riparian area, as an under-appreciated carbon sink.
Effect of Different Hardwood Species and Lay-Up Schemes on the Mechanical Properties of Plywood
Authors: Kallakas Heikko , Rohumaa Anti , Vahermets Harti , Kers Jaan
Published: June 2020

In Estonia, hardwoods form approximately 50% of all forest area, where the main species are birch (30%), gray alder (9%), aspen (6%) and black alder (4%). Birch has been extensively used by the veneer-based industry, but species like black alder, gray alder and aspen have not been commonly used by the veneer-based products industry due to the lower quality of this resource. The aim of this research is to determine the effect of different lay-up schemes and usages of gray alder, black alder and aspen on the mechanical properties of plywood, by replacing birch veneer in the plywood core with alternative wood species. The main veneer and plywood characteristics will be evaluated according to the current standards, e.g., veneer strength perpendicular to grain, plywood bonding and bending strength, and modulus of elasticity. All processing parameters will be kept similar to those used generally by birch plywood manufacturers. The results showed that birch and black alder plywood panels had generally the highest bending strength properties, followed by grey alder and aspen. It was also found that, for proper gluing, birch veneers had the lowest glue consumption, 152 g/m2, and aspen had the highest glue consumption, 179 g/m2. It was found that when lower density wood was used in the plywood, the product density increased. Low density wood veneers had higher glue consumption, and also higher compaction in thickness than birch veneers under the same pressure. Overall, it was shown that the wood species used in this study have slightly lower strength properties, but with proper lay-up schemes, these wood species could be successfully used by the veneer-based products industry.