bluuebunny/crossref_metadata_2025 huggingface dataset:
An integrated analytical study of crayons from the original art materials collection of the MUNCH museum in Oslo
Authors: La Nasa Jacopo , Doherty Brenda , Rosi Francesca , Braccini Chiara , Broers Frederique T. H. , Degano Ilaria , Matinero Jordi Moles , Miliani Costanza , Modugno Francesca , Sabatini Francesca , Sandu Irina Crina Anca , Cartechini Laura
Published: March 2021

Among the artists’ materials of the nineteenth century, pastel crayons merit scientific interest since their early commercial formulations are mostly unknown and, until now, have been considerably less studied with respect to other contemporary painting materials. In this framework, research herein reports the results of a comprehensive multi-analytical study of 44 pastel crayons of two recognized brands (LeFranc and Dr. F. Schoenfeld) from the Munch museum collection of original materials belonging to Edvard Munch. The integrated use of complementary spectroscopic and hyphenated mass-spectrometry techniques allowed the compositional profiles of the crayons to be traced providing the identification of the inorganic and organic pigments, the fillers/extenders and the binders. All crayons resulted to be oil- based and the binder was identified to be a mixture of a drying oil (safflower or linseed oil), palm oil or Japan wax and beeswax. Among others, pigments such as ultramarine, chrome yellows, Prussian blue, manganese violet, viridian and madder lake have been identified. A significant alignment in formulations of the brands was observed with the only exception of the greens which showed distinctive pigment and filler compositions. The analytical information provided for these commercial artists’ materials will be of great interest for academia, museum and other institutions hosting art collections dating from the same period and it will be used by the Munch museum to draw proper conservation strategies of its own artwork collections.
Controllable dynamics of a dissipative two-level system
Authors: Wu Wei , Zhang Ze-Zhou
Published: March 2021

We propose a strategy to modulate the decoherence dynamics of a two-level system, which interacts with a dissipative bosonic environment, by introducing an ancillary degree of freedom. It is revealed that the decay rate of the two-level system can be significantly suppressed under suitable steers of the assisted degree of freedom. Our result provides an alternative way to fight against decoherence and realize a controllable quantum dissipative dynamics.
Introducing participatory fairness in emergency communication can support self-organization for survival
Authors: Banerjee Indushree , Warnier Martijn , Brazier Frances M. T. , Helbing Dirk
Published: March 2021

Participatory resilience of disaster-struck communities requires reliable communication for self-organized rescue, as conventional communication infrastructure is damaged. Disasters often lead to blackouts preventing citizens from charging their phones, leading to disparity in battery charges and a digital divide in communication opportunities. We propose a value-based emergency communication system based on participatory fairness, ensuring equal communication opportunities for all, regardless of inequality in battery charge. The proposed infrastructure-less emergency communication network automatically and dynamically (i) assigns high-battery phones as hubs, (ii) adapts the topology to changing battery charges, and (iii) self-organizes to remain robust and reliable when links fail or phones leave the network. The novelty of the proposed mobile protocol compared to mesh communication networks is demonstrated by comparative agent-based simulations. An evaluation using the Gini coefficient demonstrates that our network design results in fairer participation of all devices and a longer network lifetime, benefiting the community and its participants.
Variable expression quantitative trait loci analysis of breast cancer risk variants
Authors: Wiggins George A. R. , Black Michael A. , Dunbier Anita , Merriman Tony R. , Pearson John F. , Walker Logan C.
Published: March 2021

Genome wide association studies (GWAS) have identified more than 180 variants associated with breast cancer risk, however the underlying functional mechanisms and biological pathways which confer disease susceptibility remain largely unknown. As gene expression traits are under genetic regulation we hypothesise that differences in gene expression variability may identify causal breast cancer susceptibility genes. We performed variable expression quantitative trait loci (veQTL) analysis using tissue-specific expression data from the Genotype-Tissue Expression (GTEx) Common Fund Project. veQTL analysis identified 70 associations (p < 5 × 10–8) consisting of 60 genes and 27 breast cancer risk variants, including 55 veQTL that were observed in breast tissue only. Pathway analysis of genes associated with breast-specific veQTL revealed an enrichment of four genes (CYP11B1, CYP17A1 HSD3B2 and STAR) involved in the C21-steroidal biosynthesis pathway that converts cholesterol to breast-related hormones (e.g. oestrogen). Each of these four genes were significantly more variable in individuals homozygous for rs11075995 (A/A) breast cancer risk allele located in the FTO gene, which encodes an RNA demethylase. The A/A allele was also found associated with reduced expression of FTO, suggesting an epi-transcriptomic mechanism may underlie the dysregulation of genes involved in hormonal biosynthesis leading to an increased risk of breast cancer. These findings provide evidence that genetic variants govern high levels of expression variance in breast tissue, thus building a more comprehensive insight into the underlying biology of breast cancer risk loci.
Neural silences can be localized rapidly using noninvasive scalp EEG
Authors: Chamanzar Alireza , Behrmann Marlene , Grover Pulkit
Published: March 2021

A rapid and cost-effective noninvasive tool to detect and characterize neural silences can be of important benefit in diagnosing and treating many disorders. We propose an algorithm, SilenceMap, for uncovering the absence of electrophysiological signals, or neural silences, using noninvasive scalp electroencephalography (EEG) signals. By accounting for the contributions of different sources to the power of the recorded signals, and using a hemispheric baseline approach and a convex spectral clustering framework, SilenceMap permits rapid detection and localization of regions of silence in the brain using a relatively small amount of EEG data. SilenceMap substantially outperformed existing source localization algorithms in estimating the center-of-mass of the silence for three pediatric cortical resection patients, using fewer than 3 minutes of EEG recordings (13, 2, and 11mm vs. 25, 62, and 53 mm), as well for 100 different simulated regions of silence based on a real human head model (12 ± 0.7 mm vs. 54 ± 2.2 mm). SilenceMap paves the way towards accessible early diagnosis and continuous monitoring of altered physiological properties of human cortical function.
Staphylococcus aureus lipoproteins promote abscess formation in mice, shielding bacteria from immune killing
Authors: Mohammad Majd , Na Manli , Hu Zhicheng , Nguyen Minh-Thu , Kopparapu Pradeep Kumar , Jarneborn Anders , Karlsson Anna , Ali Abukar , Pullerits Rille , Götz Friedrich , Jin Tao
Published: March 2021

Despite being a major bacterial factor in alerting the human immune system, the role of Staphylococcus aureus (S. aureus) lipoproteins (Lpp) in skin infections remains largely unknown. Here, we demonstrated that subcutaneous injection of S. aureus Lpp led to infiltration of neutrophils and monocytes/macrophages and induced skin lesions in mice. Lipid-moiety of S. aureus Lpp and host TLR2 was responsible for such effect. Lpp-deficient S. aureus strains exhibited smaller lesion size and reduced bacterial loads than their parental strains; the altered phenotype in bacterial loads was TLR2-independent. Lpp expression in skin infections contributed to imbalanced local hemostasis toward hypercoagulable state. Depletion of leukocytes or fibrinogen abrogated the effects induced by Lpp in terms of skin lesions and bacterial burden. Our data suggest that S. aureus Lpp induce skin inflammation and promote abscess formation that protects bacteria from innate immune killing. This suggests an intriguing bacterial immune evasion mechanism.
Multiple impacts of microplastics can threaten marine habitat-forming species
Authors: Corinaldesi Cinzia , Canensi Sara , Dell’Anno Antonio , Tangherlini Michael , Di Capua Iole , Varrella Stefano , Willis Trevor J. , Cerrano Carlo , Danovaro Roberto
Published: March 2021

Microplastics are recognised as a potential global threat to marine ecosystems, but the biological mechanisms determining their impact on marine life are still largely unknown. Here, we investigated the effects of microplastics on the red coral, a long-lived habitat-forming organism belonging to the Corallium genus, which is present at almost all latitudes from shallow-water to deep-sea habitats. When exposed to microplastics, corals preferentially ingest polypropylene, with multiple biological effects, from feeding impairment to mucus production and altered gene expression. Microplastics can alter the coral microbiome directly and indirectly by causing tissue abrasions that allow the proliferation of opportunistic bacteria. These multiple effects suggest that microplastics at the concentrations present in some marine areas and predicted for most oceans in the coming decades, can ultimately cause coral death. Other habitat-forming suspension-feeding species are likely subjected to similar impacts, which may act synergistically with climate-driven events primarily responsible for mass mortalities.
Enhancing the analysis of disorder in X-ray absorption spectra: application of deep neural networks to T-jump-X-ray probe experiments
Authors: Madkhali Marwah M. M. , Rankine Conor D. , Penfold Thomas J.
Published: March 2021

We demonstrate the power of our deep neural network to predict the X-ray absorption spectra of disordered systems in the presence of thermal energy.
Effects of the curvature gradient on the distribution and diffusion of colloids confined to surfaces
Authors: Ramírez-Garza O. A. , Méndez-Alcaraz J. M. , González-Mozuelos P.
Published: March 2021

The Brownian motion of interacting particles confined to surfaces with curvature gradients display an abundance of interesting and potentially useful properties.
Effect of (Ag, Zn) co-doping on structural, optical and bactericidal properties of CuO nanoparticles synthesized by a microwave-assisted method
Authors: Thakur Naveen , Anu  , Kumar Kuldeep , Kumar Ashwani
Published: March 2021

A microwave assisted synthesis method has been used for the fabrication of pure and (Ag, Zn) co-doped copper oxide (Cu1−x−yAgxZnyO) nanoparticles (NPs).
Synchrotron X-ray fluorescence and X-ray absorption near edge structure of low concentration arsenic in ambient air particulates
Authors: Shaltout Abdallah A. , Harfouche Messaoud , Hassan Fahmy A. S. , Eichert Diane
Published: March 2021

Utilizing the tunability of the synchrotron radiation, the occurrence of arsenic in coarse and fine particulates was investigated. Arsenic is mainly released from industrial sources and tends to settle at its source of provenance.
A photochemical ring expansion of 6- to 8-membered nitrogen heterocycles by [1,3]-sigmatropic rearrangement
Authors: Manning Morgan A. , Sun Wei , Light Mark E. , Harrowven David C.
Published: March 2021

A photochemical ring expansion of 6- to 8-membered nitrogen heterocycles can be combined with a thermal ring expansion of aminocyclobutenones to give efficient access to azocines and benzoazocines.
Unprecedented monofunctionalized β-Anderson clusters: [R1R2C(CH2O)2MnIVW6O22]6−, a class of potential candidates for new inorganic linkers
Authors: Li Qi , Wei Yongge
Published: March 2021

Novel Anderson-type polyoxomanganotungstate clusters with the β-isomer structure were synthesized and monofunctionalized with derivatives of 1,3-propanediol, and show unprecedented coordination activity as non-lacunary polyoxotungstate clusters.
Divergent functionalization of α,β-enones: catalyst-free access to β-azido ketones and β-amino α-diazo ketones
Authors: Tu Youshao , Dong Honglin , Wang Huamin , Ao Yuhui , Liu Yu
Published: March 2021

Solvent-modulated catalyst-free reactions of β-fluoroalkyl α,β-enones with TMSN3 furnish fluorinated β-azido ketones and α-diazo β-amino carbonyl compounds efficiently.
Pd-Catalysed direct C(sp2)–H fluorination of aromatic ketones: concise access to anacetrapib
Authors: Wu Qiuzi , Mao Yang-Jie , Zhou Kun , Wang Shuang , Chen Lei , Xu Zhen-Yuan , Lou Shao-Jie , Xu Dan-Qian
Published: March 2021

The direct aromatic C–H bond fluorination of ketones was developed for the first time, providing a short alternative to access anacetrapib through late-stage C–H bond fluorination.
Evidence for a lowest energy 3MLCT excited state in [Fe(tpy)(CN)3]−
Authors: Vittardi Sebastian B. , Magar Rajani Thapa , Schrage Briana R. , Ziegler Christopher J. , Jakubikova Elena , Rack Jeffrey J.
Published: March 2021

Transient absorption data of [FeII(tpy)(CN)3]− reveals spectroscopic signatures indicative of 3MLCT with a ∼10 ps kinetic component.
New nonlinear optical-active AAgGa6S10(A = K, Rb, Cs) featuring {[AgGa6S10]−}∞framework and high laser damage threshold
Authors: Li Jia-Nuo , Li Xiao-Hui , Yao Wen-Dong , Liu Wenlong , Guo Sheng-Ping
Published: March 2021

New structure-type AAgGa6S10(A = K, Rb, Cs) featuring unprecedented {[AgGa6S10]−}∞anionic framework exhibit the largest band gaps among chalcogenides containing independent Ag site, moderate SHG responses and high LIDTs.
Two new luminescent Cd(ii)-based coordination polymers by regulating the asymmetrical tetracarboxylate and auxiliary ligands displaying high sensitivity for Fe3+and CrO42−
Authors: Wu Yu , Zhong Yuyu , Kang Weiyi , Liu Yiwei , Yang Tingting , Zhou Mi , Zhou Luyi
Published: March 2021

The results showed luminescence spectra with emission intensities significantly quenched towards Fe3+and CrO42−. The low concentrations of the two ions indicate high sensitivities of the synthesized compounds towards analytes.
Is a transition metal–silicon quadruple bond viable?
Authors: Kalita Amlan J. , Rohman Shahnaz S. , Kashyap Chayanika , Ullah Sabnam S. , Baruah Indrani , Mazumder Lakhya J. , Sahu Prem P. , Guha Ankur K.
Published: March 2021

Quadruple bonding in heavier main group elements is not known albeit having four valence orbitals accessible for bonding.
Noble-metal single-atoms in thermocatalysis, electrocatalysis, and photocatalysis
Authors: Zhang Feifei , Zhu Yinlong , Lin Qian , Zhang Lian , Zhang Xiwang , Wang Huanting
Published: March 2021

This review summarizes the recent advances about noble-metal single-atom catalysts in thermocatalysis, electrocatalysis, and photocatalysis.
Continuous electrical pumping membrane process for seawater lithium mining
Authors: Li Zhen , Li Chunyang , Liu Xiaowei , Cao Li , Li Peipei , Wei Ruicong , Li Xiang , Guo Dong , Huang Kuo-Wei , Lai Zhiping
Published: March 2021

Lithium was enriched up to 10 000 ppm from seawater by a continuous electrical pumping membrane process and collected as battery-grade product by simple precipitation.
Current status and future trends of vaccine development against viral infection and disease
Authors: Wang Hong-Peng , Wang Zhi-Gang , Liu Shu-Lin
Published: March 2021

This paper focuses on the classification and representative studies of viral vaccines and future directions of vaccine design.
A new, Gaia-based, catalogue of blue straggler stars in open clusters
Authors: Rain M. J. , Ahumada J. A. , Carraro G.
Published: March 2021

Context. Blue straggler stars are exotic objects present in all stellar environments whose nature and formation channels are still partially unclear. They seem to be particularly abundant in open clusters (OCs), thus offering a unique chance to tackle these problems statistically.

Aims. We aim to build up a new and homogeneous catalogue of blue straggler stars (BSS) in Galactic OCs using Gaia to provide a more solid assessment of the membership of these stars. We also aim to explore possible relationships of the straggler abundance with the parent cluster’s structural and dynamical parameters. As a by-product, we also search for possible yellow straggler stars (YSS), which are believed to be stragglers in a more advanced evolution stage.

Methods. We employed photometry, proper motions, and parallaxes extracted from Gaia DR2 for 408 Galactic star clusters and searched for stragglers within them after performing a careful membership analysis.

Results. The number of BBS emerging from our more stringent, selection criteria turns out to be significantly smaller than in previous versions of this catalogue. OCs are therefore not a preferable environment for these kinds of stars anymore. In addition, we found that BSS start to appear in clusters with ages larger than log(t) ∼ 8.7 and are therefore absent in very young star clusters.

Conclusions. The present catalogue supersedes the previous ones in several ways: membership assessment, number of stragglers found, and so forth. The new list includes 897 BSS and 77 YSS candidates in 408 OCs. We expect this catalogue to be the basis for a new round of studies of BSS and YSS.
The ASTRODEEP-GS43 catalogue: New photometry and redshifts for the CANDELS GOODS-South field
Authors: Merlin E. , Castellano M. , Santini P. , Cipolletta G. , Boutsia K. , Schreiber C. , Buitrago F. , Fontana A. , Elbaz D. , Dunlop J. , Grazian A. , McLure R. , McLeod D. , Nonino M. , Milvang-Jensen B. , Derriere S. , Hathi N. P. , Pentericci L. , Fortuni F. , Calabrò A.
Published: March 2021

Context. We present ASTRODEEP-GS43, a new multi-wavelength photometric catalogue of the GOODS-South field, which builds and improves upon the previously released CANDELS catalogue.

Aims. We provide photometric fluxes and corresponding uncertainties in 43 optical and infrared bands (25 wide and 18 medium filters), as well as the photometric redshifts and physical properties of the 34930 CANDELS H-detected objects, plus an additional sample of 178 H-dropout sources, of which 173 are Ks-detected and five are IRAC-detected.

Methods. We keep the CANDELS photometry in seven bands (CTIO U, Hubble Space Telescope WFC3, and ISAAC-K) and measure from scratch the fluxes in the other 36 (23 from Subaru SuprimeCAM and Magellan Baade FourStar and the rest from VIMOS, HST ACS, HAWK-I Ks, and Spitzer IRAC) with state-of-the-art template-fitting techniques. We then compute new photometric redshifts with three different software tools and take the median value as a best estimate. We finally evaluate new physical parameters from spectral energy distribution (SED) fitting, comparing them to previously published ones.

Results. Comparing to a sample of 3931 high quality spectroscopic redshifts, for the new photometric redshifts we obtain a normalised median absolute deviation of 0.015, with 3.01% of outliers on the full catalogue (0.011 and 0.22% on the bright end at I814 <  22.5). This is similar to the best available published samples of photometric redshifts, such as the COSMOS UltraVISTA catalogue.

Conclusions. The ASTRODEEP-GS43 results are in qualitative agreement with previously published catalogues of the GOODS-South field, improving on them particularly in terms of SED sampling and photometric redshift estimates. The catalogue is available for download from the ASTRODEEP website.
Evaluating uncertainty in sensory analysis. A case study of the panel of tasters of the Dão Regional Wine Commission
Authors: Pinto Manuel Maria
Published: March 2021

Metrological reliability in the sensory evaluation of products is of fundamental importance in ensuring the comparability of results. The issue of uncertainties regarding measured data in such contexts has led to new scientific approaches in the field of sensory analysis, which have become fundamental to studies that seek to compare results of sensory measurement and analysis, including studies regarding wine. The new normative framework, ISO/IEC 17025:2017, which replaces the previous version ISO/IEC 17025, published in 2005, draws attention to the concept of measurement uncertainty, stating that it should be considered by laboratories when assessing conformity and quantifying risks arising in decision-making processes. The present work examines the evaluation of uncertainty and its importance for the interpretation of results from sensory analyses, examining sensory analysis tests related to the certification of the Designation of Origin “Dão”, the Designation of Origin “Lafões” and the Geographical Indication “Terras do Dão”, carried out by a panel composed of 20 tasters of the Dão Regional Wine Commission, trained and accredited by the standard NP ISO/IEC 17025:2018. The results achieved led to a conclusion that the panel presented different values of uncertainty regarding the tests to determine sensory attributes. The results and respective values of uncertainty made it possible to assess the performance of the panel of tasters and to establish a level of risk (false accept, false reject and statistical assumptions) for decision rules used when issuing statements of conformity. In this study, a new methodology was presented to determine an estimate of uncertainty to be applied in the interpretation of results related to sensory analysis tests of wines for the certification of Designation of Controlled Origin “Dão”, Designation of Origin “Lafões” and Geographical Indication “Terras do Dão. This progress led to an evolution in the day-to-day work of the Dão Regional Wine Commission tasting chamber enabling greater solidity in the opinions issued, in line with the requirements of the reference standard NP ISO/IEC 17025: 2018.
Assessment of health risks related to groundwater consumption in Al-Hoceima region
Authors: Mchiouer Fatiha , El Ouarghi Hossain , Benyoussef Said , Abourrich Mustapha
Published: March 2021

Water is a precious natural resource for life, and more vulnerable to different contaminations; it has become less and less drinkable because it is polluted and can carry pathogenic germs that cause water diseases. The population of the Al-Hoceima region is supplied with drinking water from the network of the National Drinking Water Board, which is not widespread in rural areas where there is the frequent use of communal water points (spring or well). Health concerns remain related to the consumption of untreated well water, in the absence of a department responsible for the management of well water (development, equipment, treatment, protection, and quality control). To preserve the health of the population from any source of contamination carried by water, the Ministry of Health, carries out, through the provincial hygiene services, the control and monitoring of the physical-chemical and bacteriological quality of water in the framework of the fight against water diseases. The objective of this work was to determine the state of groundwater quality in the Al-Hoceima region, based on the study of physicochemical and bacteriological parameters. A control of 41 collective water points was carried out, including 30 wells and 11 springs. The collected samples were analyzed to measure some physical parameters: electrical conductivity, pH, temperature, and dissolved oxygen, possibly looking for indicator germs of fecal contamination, namely coliform bacteria, Escherichia coli, and intestinal enterococci. The results revealed fecal contamination of all collective water points by coliform bacteria and Escherichia coli. Appropriate measures must be taken for the disinfection of these waters before their use.
Fungicides against mildew case of Potato (Solanum tuberosum .L.) from the Triffa plain, irrigated area of Moulouya
Authors: Alaoui Karima , Chafik Zouheir , Kharmach Ez-zahra
Published: March 2021

The 2016-2017 agricultural season was devoted to prospecting in different farms in the Triffa Plain. Mildew is present in almost all areas of the plain, given the favourable climatic conditions. Around 95% of the potato cultivated areas in the irrigated area of Moulouya are concentrated only in the Triffa plain, from which 51 plots have been identified. This survey showed that a total of 34 plots (476 hectares covering about 22% of the total area under potato cultivation) were attacked differently by the late blight, and the area managed by the Agricultural Valorization Center (AVC 108) showed the highest attack degree .Preventive control is the most used measure by farmers to protect their crops from attacks by this pathogenic fungus. More than 89% of farmers apply chemicals with health protection measures that are often insufficient or totally absent (77% of farmers apply 4 to 6 fungal treatments per cycle). However, the non-rational use of these chemicals revealed serious problems that are harmful to the various environment components, namely fauna and especially human beings’ health. The results obtained in this study recommend the use of rather organic and ecological treatments that are favourable for the preservation of human health and guarantee a sustainable and healthy agricultural production.
Self-absorption Correction Factors: Applying A Simplified Method to Analysis of Lead-210 in Different Environment Samples by Direct Counting of Low-energy Using HPGe Detector
Authors: Al-Tuweity Jawaher , Kamleh Hassan , Al-Masri M. Said , Doubal A. Wael , Chakir El Mahjoub
Published: March 2021

This study aimed to determine the self-absorption correction factors of lead-210 (210Pb) in various Syrian environment samples. Seven sediments, five soils, and four plant samples were analysed by Gamma Spectroscopy using simple and direct analysis method called Cutshall. The method is based on measuring the penetration of gamma which emitted from a standard source, prepared in the laboratory by deposition of QCYB40 Standard Solution on stainless steel disk. The source was placed on top of the studied sample and the reference air sample during the measurement. The purpose was to study the self-absorption inside each sample by calculation of its self-absorption factors without knowing its chemical composition. The self-absorption correction results for the sediment samples SE3, SE6 and SE8 ranged between 36% and 45%, and 34% to 42% for the soil samples S5 and S1, respectively. Also, for the four plant samples, it recorded variance range from 4% to 18%. This is due to the difference in the density of the G4 sample, which appeared to be very low. However, the self-absorption correction factors CF were set for the different environmental samples, and the results show that the density factor of the sample is not the only influent factor in the CF values for low energies measurement, the sample chemical composition (sample matrix) is also more effective in addition to the samples’ particle sizes.
Modelling effect of temperature and irradiance changes of Assa, Morocco on photovoltaic modules’ performance
Authors: Chakiri Siham , Lamchich My Tahar
Published: March 2021

A mathematical representation of a photovoltaic (PV) solar cell and module performances is demonstrated in this paper. One diode based on the Shockley diode equation model is adopted for simulation and extract the performance indications. The simulated solar module is a particular 235W solar module operating in an existing 806.52 kWp grid connected photovoltaic power plant located at Assa, southern Morocco. The model demonstrates power-voltage (P-V) and current-voltage (I-V) characteristic curves with weather conditions changes. These external conditions include temperature and solar irradiance level (represented by sun unit 1sun=1000w/m2) which greatly affect the performance of the PV system. This paper also presents PV simulation with a maximum power point tracking (MPPT) converter and the general model was implemented in Matlab/Simulink software and used as an example verifying the performance of the tested module under Assa city weather variable.
The model of neoclusterization as a theoretical basis of innovative development of the agricultural sector of the Volga region
Authors: Napolskikh Dmitry
Published: March 2021

This article examines the contradictions and the characteristics of clustering and innovative development in the agricultural sector. The author’s approach focused on the development of an integrated clustering model of the Volga Region economic space, considering clusters as the fundamental segments of the agricultural sector. The international experience in coordination of territorial and agricultural cluster development was taken into account, the characteristics of the implementation of the Russian cluster policy are attributed. A set of parameters were collected in order to be able to characterize different approaches to cluster policy, depending on the territorial or sectoral affiliation of the cluster. The general directions of improvement of the cluster policy of the Russian Federation within the framework of the neoclusterization model were taken into consideration.
The Study of Co2 Concentration in A Classroom During The Covid-19 Safety Measures
Authors: Zemitis Jurgis , Bogdanovics Raimonds , Bogdanovica Snezana
Published: March 2021

The COVID-19 crisis has affected the process of how the study procedures are organized at schools in Latvia. Three different options were available for the school to choose from. However, most schools have opted for option A which states that the classes are organized face-to-face but various safety measures must be ensured. Each class or group is equated to a closed set where there are no distance requirements. In turn, the distance between the classes must be observed. This means that students stay in the same class all day and are accompanied by teachers of the respective classes. This can lead to improper ventilation as for most of the schools in Latvia it is organized through the opening of windows. To test this, measurements of CO2 concentration were done in a classroom Secondary School in Daugavpils. The results showed that the CO2 concentration was very high and often reached and exceeded the maximum measuring capacity of the device - 4000 ppm. It indicates that following the special safety procedures cause a negative effect on IAQ as the classrooms are not properly ventilated. This can lead to a drop in the performance of pupils as well as stimulate the transmission of other infectious diseases. Further measurements are necessary to gather data from different schools and best practices must be found.
A study on the relationship between energy performance and IEQ parameters in school buildings
Authors: Cabovská Blanka , Teli Despoina , Dalenbäck Jan-Olof , Langer Sarka , Ekberg Lars
Published: March 2021

Over the last decades, strong focus has been placed on the energy efficiency of buildings; not least school buildings. Energy performance (EP) of buildings is nowadays in principle described by one single indicator based on purchased energy in kWh/year.m2. Another important building performance aspect is the indoor environmental quality. This study’s overarching goal is to identify school buildings with a good balance between energy performance and indoor environment. Thus, this paper investigates possible correlations between information given in energy performance certificates (EPCs/e.g. energy use, year of construction, type of ventilation) and measured indoor environmental parameters. The work comprises investigation of approximately 20 school buildings with different ventilation systems in Gothenburg. In-situ investigations of the buildings’ properties and ventilation systems were conducted. Indoor environmental parameters were recorded during one week in each classroom. In this paper, indoor temperature, absolute humidity added indoors and CO2 concentration data are compared with the corresponding school’s energy performance data and ventilation type. Results suggest that mechanically ventilated buildings have clearer relationships between energy performance, building indicators and measured indoor environment. For buildings such as naturally ventilated, the relationships are usually weak, and the values spread over much wider ranges.
The climate adaptability evaluation of biogas fermentation assisted by solar greenhouse
Authors: Shao Xiaolu , Su Xing , Tian Shaochen , Cai Jian
Published: March 2021

The production efficiency of biogas digesters is largely restricted by the low environment temperature in winter, for most regions of China. As a feasible means of warming and heat preservation, solar greenhouse has the ability to expand the application scope and service time of biogas in rural China. The evaluation of climate adaptability of solar greenhouse is of great importance and imminent, due to the fact that both solar energy and biomass resources are affected by climate. In this paper, a complete evaluation index system for climate adaptability of biogas fermentation assisted by solar greenhouse was established. The indicators of the evaluation index system were selected by means of frequency analysis and theoretical analysis. The weights of the indicators, including solar radiation, outdoor air temperature, crop yields and human and animal manure, were determined by analytic hierarchy process combined with literature research, and the scoring rules were based on the objective significance of each indicator. The climate adaptability of typical cities in the Yangtze River Delta was evaluated with the evaluation index system. Among the cities, Hefei shows the best comprehensive adaptability, and then is Xuzhou, Shanghai, Nanjing, and the lowest adaptability, Hangzhou. The comprehensive adaptability results of these cities depend not only on the gas production capacity, but also on the biomass resource and solar radiation.
Parametric Cost Optimization of Solar Systems with Seasonal Thermal Energy Storage for Buildings
Authors: Villasmil Willy , Troxler Marcel , Hendry Reto , Schuetz Philipp , Worlitschek Jörg
Published: March 2021

In combination with seasonal thermal energy storage (STES), solar energy offers a vast potential for decarbonizing the residential heat supply. In this work, a parametric optimization is conducted to assess the potential of reducing the costs of water-based STES through the use of alternative thermal insulation materials and the integration of an underground storage outside the building. The investigated configurations include: a hot-water tank, a solar collector installation, and a multifamily building with a solar fraction of 100%. The storage is either integrated inside the building or buried underground in its direct vicinity. A simulation-based analysis shows that if the tank is integrated inside an existing building (as part of a retrofitting action) – where costs are primarily driven by the loss of living space – vacuum-insulation panels can lead to significant savings in living space and a cost advantage compared to the use of conventional glass wool. Nevertheless, storage integration inside an existing building is a more expensive option compared to an external integration due to the high costs associated to the internal building modification and loss of living space. Despite the high excavation costs and increased heat losses, the concept of burying the storage underground is a promising option to allow the integration of large-volume seasonal storage systems in new and existing buildings.
Tenant-based measured electricity use in 4 large office buildings in Tallinn, Estonia
Authors: Ferrantelli Andrea , Aljas Hans Kristjan , Maask Vahur , Thalfeldt Martin
Published: March 2021

The energy performance assessment of buildings during design is usually based on energy simulations with pre-defined input data from standards and legislations. Typically, the internal gain values and profiles are based on EN 16798–1. However, studies have shown that the real electricity use of plug load and lighting varies more smoothly than in the profiles of EN 16798–1 where zero occupancy outside working hours is assumed. This might result in sub-optimal building solutions due to inadequate building performance simulation input data. The aim of this work is to structure and analyse data from a total of 196 electricity meters in 4 large office buildings in Tallinn, Estonia. Typically, 3 to 8 electricity meters were installed per floor with the consumption coming mainly from plug loads and electric lighting. The data had been gathered between the years 2016–2020 with either 1 or 24 hour time steps, depending on the building and the electricity meter. 3 out of the 4 buildings had an average normalized energy usage slightly below the modelling value calculated according to EN16798–1. Some office spaces stood out with an abnormally high electricity consumption, however, the 24-hour distributions were fairly compact, meaning quite steady consumption patterns. When looking at the dispersion of energy consumption per 24h, averaged over all given offices in a building, no outliers stood out, either. This means that there are not many days when the average consumption and internal heat gains of all offices were simultaneously well below the mean. Additionally, major events like holidays and the COVID19-induced lockdown show up well on the graphs, but also planned changes in occupancy can be seen.
Investigation and prediction of Energy consumption at St. Olavs Hospital
Authors: Smedsrud Kristofersen, by Hans , Xue Kai , Yang Zhirong , Stenstad Liv-Inger , Giske Tor Emil , Cao Guangyu
Published: March 2021

The objective of this study is to evaluate and predict the energy use in different buildings during COVID-19 pandemic period at St. Olavs Hospital in Trondheim. Based on machine learning, operational data from St. Olavs hospital combined with weather data will be used to predict energy use for the hospital.

Analysis of the energy data showed that the case buildings at the hospital did not have any different energy use during the pandemic this year compared to the same period last year, except for the lab center. The energy consumption of electricity, heating and cooling is very similar both in 2019 and 2020 for all buildings, but in 2020 during the pandemic, the lab center had a reduction of 35% in electricity, compared to last year. An analysis of the energy needed for heating and cooling in the end of June to the end of November was also calculated for operating room 1 and was estimated to 256 kWh/m2 for operation room 1.

The machine learning algorithms perform very well to predict the energy consumption of case buildings, Random Forest and AdaBoost proves as the best models, with less than 10% margin of error, some of the models have only 4% error.

An analysis of the effect of humidification of ventilation air on energy consumption in operating room 1 was also carried out. The impact on energy consumption were high in winter and will at the coldest periods be able to double the energy consumption needed in the ventilation.
Thermal-electrical Measurement System – a modular, expandable Concept for short-term energy recordings in Buildings
Authors: Seidel Paul , Seifert Joachim , Wolffgang Karl
Published: March 2021

In the context of the energy transition in Germany energy-optimized and resource-saving buildings and building systems are being installed. To be able to do this, it is necessary to obtain information from the buildings, such as peak or base load of heating/cooling and electrical consumption. In the following publication a developed short-term analysis system based on a modular non-invasive measurement system will be described. Additional first results from a field test will be presented.
Impact of office tenants’ electricity use on the cost-optimal solutions in a cold climate
Authors: Kuivjõgi Helena , Laas Liina , Ferrantelli Andrea , Thalfeldt Martin
Published: March 2021

The buildings’ energy performance requirements in Estonia are based on cost-optimality analysis according to the EPBD and pre-defined building performance simulation (BPS) input data from EN 16798-1:2019. Previous studies have shown that the real electricity use of office building tenants differs from the currently used input data in BPS in Estonia – less in total energy use, but more in the shape of the profiles. The aim of this work is to investigate what is the impact of these differences on the cost-optimal solutions, which are identified based on BPS and the self-consumption of the photovoltaic panel (PV) systems. This study describes the energy performance and construction cost analysis of a new office building in Tallinn, Estonia. BPS based on the EN 16798-1 and a model derived from measurements in a real building were conducted and cost-optimal building solutions identified. The variables were building envelope insulation thickness, air handling unit size and effectiveness, electrical lighting control principles and PV system nominal power. The calculated energy use of the building with the two different sets of input data differed significantly. However, the set of cost-optimal solutions identified with EN 16798-1:2019 input data had minor differences from the set of solutions identified with the more realistic model. The decrease of net present value over 20-year period for cost-optimal solution was 11-14 €/m2 compared to the designed building.The realistic office tenants’ electricity model increased the calculated self-consumption of the PV system from 95% to 100%.
A multi-stakeholder perspective on opportunities and challenges for energy efficiency improvement in university buildings
Authors: Nair Gireesh , Azizi Shoaib , Olofsson Thomas
Published: March 2021

University buildings are relatively energy-intensive. In Sweden, universities usually operate in rented buildings. In this study, interviews were carried out among three categories of stakeholders in a Swedish university to understand their perceptions of energy use and challenges to improve energy efficiency. As per most interviewees, the university’s top management and Akademiska Hus, which owns the buildings, have the main responsibility to reduce the buildings’ energy and carbon footprint. The heads of departments raised the concern on the non-availability of energy data to take actions to reduce energy use. The use of sensors and information technologies to monitor space use, energy use, and indoor environment are attractive to different stakeholders. The implications of the interview results are discussed.
Assessment of three solar-assisted heat pump typologies in Canada: parallel, series, and ice storage
Authors: Beauchamp Benjamin , Brideau Sébastien , Cruickshank Cynthia
Published: March 2021

This paper discusses the energy savings, operating costs, and net present values of three typologies of solar assisted heat pump in Canada: parallel systems, series systems, and ice storage systems. Typologies are evaluated for three detached house archetypes of varying energy performances, and across a variety of Canadian climates. Hourly energy modelling is accomplished with a custom spreadsheet tool. The models developed are approximate and meant for high level analysis. This work is meant as a first step in a process of verifying the potential for each of the typologies. In most cases, the parallel system performs best in terms of annual energy savings. The paper goes over the models, assumptions, and some results. Recommendations are discussed for future research focusing on system payback times. The next step will consist of using a detailed sub-hourly simulation tool for the typology that has been found to be the most promising.
Study of a water-source CO2 heat pump for residential use: experimental discharge pressure control and performance analysis
Authors: Li Yantong , Nord Natasa , Rekstad Inge Håvard , Skånøy Stein Kristian , Sørensen Lars Konrad
Published: March 2021

The heat pumps with the refrigerant of carbon dioxide (CO2), i.e., CO2 heat pumps, have the merits of low price and environmentally friendliness in comparison with those with traditional refrigerants, e.g., hydrochlorofluorocarbons and chlorofluorocarbons. Current studies mainly focused on the air-source CO2 heat pumps, while investigations about the CO2 heat pumps gaining heat or cold energy from different mediums, e.g., water, are lacking. In addition, although few studies presented the investigations on the discharge pressure of the CO2 heat pumps (e.g., investigations of optimal discharge pressure), how to realize the effective discharge pressure control in the experimental conditions is still lacking. To remedy these knowledge gaps, this study presented an experimental investigation of a water-source CO2 heat pump for residential use. A PI controller was used to maintain the fixed discharge pressure by adjusting the opening of the electronic expansion valve. The dynamic performance of the CO2 heat pump in the typical discharge pressure of 7,200 to 8,400 kPa were analyzed. The results indicated that the method of using the PI controller to adjust the opening of the electronic expansion valve could effectively maintain the desired discharge pressure of the CO2 heat pump in the experimental conditions.
Sizing and performance analyses of a combined heating and cooling system with the integration of short- and long-term storages
Authors: Shakerin Mohammad , Eikeskog Vilde , Li Yantong , Thorgeir Harsem T. , Nord Natasa
Published: March 2021

Technological advancements in the utilization of renewable energy sources have unveiled potentials for increasing building energy efficiency. Integrating heat pump-based energy systems with thermal storages is a suitable option to meet the thermal requirements of modern buildings and exploiting the available renewable energy sources. However, how to size the main components of a heat pump-based energy system with the integration of short- and long-term storages is not yet well explored. Therefore, this study focused on the design and performance analyses of an integrated heating and cooling system consist of a heat pump, borehole long-term thermal storage, and hot water tank short-term thermal. Heat pump models were introduced as parametric models based on the producer data. The dynamic thermal model of the energy system was developed and analysed in MATLAB. Different combinations of heating and cooling loads were tested. Integration of cooling and heating systems was discussed through different operation strategies and challenges were addressed. The results of the parametric analysis identified the key parameters affecting the design of components and efficiency of the system. Moreover, the results showed that lower cooling to heating load ratio leads to an excessive reduction of the ground temperature and overall efficiency over the long-term operation.