bluuebunny/crossref_metadata_2025 huggingface dataset:
The umami receptor T1R1–T1R3 heterodimer is rarely formed in chickens
Authors: Yoshida Yuta , Kawabata Fuminori , Nishimura Shotaro , Tabata Shoji
Published: June 2021

The characterization of molecular mechanisms underlying the taste-sensing system of chickens will add to our understanding of their feeding behaviors in poultry farming. In the mammalian taste system, the heterodimer of taste receptor type 1 members 1/3 (T1R1/T1R3) functions as an umami (amino acid) taste receptor. Here, we analyzed the expression patterns of T1R1 and T1R3 in the taste cells of chickens, labeled by the molecular markers for chicken taste buds (vimentin and α-gustducin). We observed that α-gustducin was expressed in some of the chicken T1R3-positive taste bud cells but rarely expressed in the T1R1-positive and T2R7-positive taste bud cells. These results raise the possibility that there is another second messenger signaling system in chicken taste sensory cells. We also observed that T1R3 and α-gustducin were expressed mostly in the vimentin-positive taste bud cells, whereas T1R1 and bitter taste receptor (i.e., taste receptor type 2 member 7, T2R7) were expressed largely in the vimentin-negative taste bud cells in chickens. In addition, we observed that T1R1 and T1R3 were co-expressed in about 5% of chickens' taste bud cells, which express T1R1 or T1R3. These results suggest that the heterodimer of T1R1 and T1R3 is rarely formed in chickens’ taste bud cells, and they provide comparative insights into the expressional regulation of taste receptors in the taste bud cells of vertebrates.
Prediction of functional properties of nano $$\hbox {TiO}_2$$ coated cotton composites by artificial neural network
Authors: Amor Nesrine , Noman Muhammad Tayyab , Petru Michal
Published: June 2021

This paper represents the efficiency of machine learning tool, i.e., artificial neural network (ANN), for the prediction of functional properties of nano titanium dioxide coated cotton composites. A comparative analysis was performed between the predicted results of ANN, multiple linear regression (MLR) and experimental results. ANN was applied to map out the complex input-output conditions to predict the optimal results. A backpropagation ANN model called a multilayer perceptron (MLP), trained with Bayesian regularization were used in this study. The amount of chemicals and reaction time were selected as input variables and the amount of titanium dioxide coated on cotton, self-cleaning efficiency, antimicrobial efficiency and ultraviolet protection factor were analysed as output results. The accuracy of the proposed algorithm was evaluated and compared with MLR results. The obtained results reveal that MLP provides efficient results that are statistically significant in the prediction of functional properties ($$p<0.1 e^{-10} $$

p
<
0.1

e

-
10

) compared to MLR. The correlation coefficient of MLP model ($$>95\%$$

>
95
%

) indicates that there is a strong correlation between the measured and predicted functional properties with a trivial mean absolute error and root mean square errors values. MLP model is suitable for the functional properties and can be used for the investigation of other properties of nano coated fabrics.
Elovanoids downregulate SARS-CoV-2 cell-entry, canonical mediators and enhance protective signaling in human alveolar cells
Authors: Calandria Jorgelina M. , Bhattacharjee Surjyadipta , Maness Nicholas J. , Kautzmann Marie-Audrey I. , Asatryan Aram , Gordon William C. , Do Khanh V. , Jun Bokkyoo , Mukherjee Pranab K. , Petasis Nicos A. , Bazan Nicolas G.
Published: June 2021

The pro-homeostatic lipid mediators elovanoids (ELVs) attenuate cell binding and entrance of the SARS-CoV-2 receptor-binding domain (RBD) as well as of the SARS-CoV-2 virus in human primary alveoli cells in culture. We uncovered that very-long-chain polyunsaturated fatty acid precursors (VLC-PUFA, n-3) activate ELV biosynthesis in lung cells. Both ELVs and their precursors reduce the binding to RBD. ELVs downregulate angiotensin-converting enzyme 2 (ACE2) and enhance the expression of a set of protective proteins hindering cell surface virus binding and upregulating defensive proteins against lung damage. In addition, ELVs and their precursors decreased the signal of spike (S) protein found in SARS-CoV-2 infected cells, suggesting that the lipids curb viral infection. These findings open avenues for potential preventive and disease-modifiable therapeutic approaches for COVID-19.
Publisher Correction: Age-dependence of electromagnetic power and heat deposition in near-surface tissues in emerging 5G bands
Authors: Sacco Giulia , Pisa Stefano , Zhadobov Maxim
Published: June 2021

An
The economic outlook for converting CO2 and electrons to molecules
Authors: Huang Zhe , Grim R. Gary , Schaidle Joshua A. , Tao Ling
Published: June 2021

Comprehensive techno-economic analysis across a wide set of technologies and products provides insight into the economic feasibility of electron-mediated CO2 reduction.
Synthesis and modification of carbon dots for advanced biosensing application
Authors: Wang Fu-Ting , Wang Li-Na , Xu Jing , Huang Ke-Jing , Wu Xu
Published: June 2021

The synthesis and modification strategies of CDs are summarized, and their applications, challenges and future prospects in advanced biosensors are discussed.
Expanding current applications and permitting the analysis of larger intact samples by means of a 7 mm CMP–NMR probe
Authors: Ning Paris , Lane Daniel , Ghosh Biswas Rajshree , Jenne Amy , Bastawrous Monica , Soong Ronald , Schmidig Daniel , Frei Thomas , De Castro Peter , Kovacevic Ivan , Graf Stephan , Wegner Sebastian , Bermel Wolfgang , Busse Falko , Kuehn Till , Kuemmerle Rainer , Struppe Jochem , Fey Michael , Stronks Henry J. , Monette Martine , Simpson Myrna J. , Simpson André J.
Published: June 2021

With a larger sample size, 7 mm CMP–NMR can identify and distinguish components in different phases within a softgel capsule of hydroxyzine hydrochloride. The capsule would not fit in a 4 mm probe.
Electrochemical nitrogen reduction: recent progress and prospects
Authors: Chanda Debabrata , Xing Ruimin , Xu Tong , Liu Qian , Luo Yonglan , Liu Shanhu , Tufa Ramatu Ashu , Dolla Tarekegn Heliso , Montini Tiziano , Sun Xuping
Published: June 2021

Electrochemical nitrogen reduction reaction (ENRR) is regarded as a green process for ammonia production. This work provides a comprehensive review on recent advance in the ENRR process. Opportunities and future directions of it are also discussed.
Layered assembly of cationic and anionic supramolecular polymers
Authors: Jevric Jovana , Langenegger Simon M. , Häner Robert
Published: June 2021

The self-assembly of cationic aromatic oligoamines into vesicles and their interaction with anionic supramolecular nanosheets is presented.
Amide bond formation: beyond the dilemma between activation and racemisation
Authors: Muramatsu Wataru , Hattori Tomohiro , Yamamoto Hisashi
Published: June 2021

The development of methods for amide bond formation without recourse to typical condensation reagents has become an emerging research area and has been actively explored in the past quarter century.
First principles characterisation of bio–nano interface
Authors: Rouse Ian , Power David , Brandt Erik G. , Schneemilch Matthew , Kotsis Konstantinos , Quirke Nick , Lyubartsev Alexander P. , Lobaskin Vladimir
Published: June 2021

We present a multiscale computational approach for the first-principles study of bio-nano interactions. Using titanium dioxide as a case study, we evaluate the affinity of titania nanoparticles to water and biomolecules through atomistic and coarse-grained techniques.
Strong bases behave as weak bases in nanoscale chemical environments: implication in humidity-swing CO2air capture
Authors: Han Yingying , Zhu Liangliang , Yao Yutong , Shi Xiaoyang , Zhang Yayun , Xiao Hang , Chen Xi
Published: June 2021

The reaction of guanidine–H2O and guanidine–CO2 in nanoscale chemical environments was studied using ab initio calculations, which can provide valuable theoretical guidance for the design of CO2 air capture sorbents using guanidine-based materials.
Microbial synthesis of vanillin from waste poly(ethylene terephthalate)
Authors: Sadler Joanna C. , Wallace Stephen
Published: June 2021

An engineered biosynthetic pathway in Escherichia coli enables the one-pot upcycling of post-consumer plastic waste into vanillin.
Selective electrocatalytic CO2 reduction to acetate on polymeric Cu–L (L = pyridinic N and carbonyl group) complex core–shell microspheres
Authors: Guo Fei , Liu Bing , Liu Mengping , Xia Yu , Wang Tianlong , Hu Wei , Fyffe Phoebe , Tian Lihong , Chen Xiaobo
Published: June 2021

Highly selective electrochemical reduction of CO2 into acetate (only acetate is produced besides H2) is reported with polymeric Cu–L (L = pyridinic N and carbonyl group) complex core–shell microspheres.
Construction of defective cobalt oxide for methane combustion by oxygen vacancy engineering
Authors: Zhang Xin , Jin Xin , Bao Liurui , Zhang Mingchao , Song Ruiming , Yu Wei , Zhang Hongbo , Huang Wei , Su Weiguang , Li Xingyun
Published: June 2021

Defects are pivotal to endow metal oxide catalysts with an efficient catalytic oxidation ability.
Towards more accurate solubility measurements with real time monitoring: a carvedilol case study
Authors: Csicsák Dóra , Borbás Enikő , Kádár Szabina , Tőzsér Petra , Bagi Péter , Pataki Hajnalka , Sinkó Bálint , Takács-Novák Krisztina , Völgyi Gergely
Published: June 2021

Study of factors like type of polymorphs, pH and buffer composition influencing the equilibrium time of carvedilol using in situ UV-probes.
Piezochromism of cyanostilbene derivatives: a small structural alteration makes a big photophysical difference
Authors: Zhu Chenfei , Li Chengjian , Wen Li , Song Qingbao , Wang Kai , Lv Chunyan , Zhang Yujiang
Published: June 2021

We designed two HLCT-active luminophores with high PLYQs. Under high pressure, DPMO presents better sensitivity and a smaller PL wavelength redshift than TPPA due to the high PLYQs and the strong CT state.
Visible-light driven redox system of water-soluble zinc porphyrin and platinum nanoparticles for selective reduction of pyruvate to lactate
Authors: Kita Yu , Amao Yutaka
Published: June 2021

A selective pyruvate reduction to lactate using a visible light-driven redox system consisting of water-soluble zinc porphyrin as a photosensitizer, methylviologen as an electron mediator and platinum nanoparticles dispersed on poly(vinylpyrrolidone) as a catalyst, is developed as a new lactate production method without toxic substances.
Promoting the conversion of CO2 to CH4via synergistic dual active sites
Authors: Fu Zhanzhao , Li Qiang , Bai Xiaowan , Huang Yuhao , Shi Li , Wang Jinlan
Published: June 2021

Regulating the coordination environment of the SACs to promote the conversion of CO2 to CH4.
Differential expression of miRNAs as biomarkers for predicting the outcomes of diffuse large B-cell lymphoma patients
Authors: Hu Maogui , Wang Xinchen , Liu Ning , Ding Kaiyang , Zhang Guihong , Liu Xiaosi
Published: June 2021

Background: Diffuse large B-cell lymphoma (DLBCL) used to be defined as germinal center B-like and non-germinal center B-like subtypes, associated with different prognoses, but the conventional classification does not meet the needs of clinical practice because of DLBCL heterogeneity, a problem that might be improved by selection of miRNAs as biomarkers.

Methods: Twelve patients with DLBCLs were used to screen out the aberrant miRNA profile using miRNA microarray technology in two patient subtypes (six germinal center B-like and six non-germinal center B-like patients). The potential biomarkers were further analyzed using the quantitative reverse transcription-polymerase chain reaction method in 95 DLBCL patients to investigate relationships among expression levels of potent miRNA, clinicopathological features and survival rates of patients.

Results: miR-208a-5p, miR-296-5p and miR-1304-5p were screened as potential biomarkers. miR-208a-5p and miR-296-5p were shown to be associated with better survival of patients after Kaplan–Meier analysis, whereas miR-1304-5p overexpression indicated a poor survival prognosis independent of the DLBCL subtype. In addition, changes of miR-296-5p and miR-1304-5p expression, the International Prognostic Index (IPI) status and the age of patients were all independent indicators for DLBCL prognosis. We also found that high miR-208a-5p expression led to better outcomes in DLBCL patients with similar IPI scores; however high miR-1304-5p expression tended to indicate the opposite.

Conclusions: MiR-208a-5p, miR-296-5p and miR-1304-5p levels might be potential biomarkers for the prediction of the prognosis of DLBCL patients.
Metabolic reprograming of antioxidant defense: a precision medicine perspective for radiotherapy of lung cancer?
Authors: Matschke Johann , Larafa Safa , Jendrossek Verena
Published: June 2021

Radiotherapy plays a key role in the management of lung cancer patients in curative and palliative settings. Traditionally, radiotherapy was either given alone or in combination with surgery, classical cytotoxic chemotherapy, or both. Technical and physical innovations achieved during the last two decades have helped to enhance the accuracy of radiotherapy dose delivery and have facilitated geometric radiotherapy individualization. Furthermore, multimodal combinations with molecularly tailored drugs or immunotherapy yielded promising survival benefits in selected patients. Yet high locoregional failure rates and frequent development of metastases still limit the patient outcome. One major obstacle to successful treatment is the high molecular heterogeneity observed in lung cancer. So far, clinical radiotherapy does not routinely use the knowledge on molecular subtypes with regard to therapy individualization and predictive biomarkers are missing. Herein, altered cancer metabolism has attracted novel attention during recent years as it promotes tumor growth and progression as well as resistance to anticancer therapies. The present perspective will exemplarily highlight how clinically relevant molecular subtypes defined by co-occurring somatic mutations in KRAS-driven lung cancer impact the metabolic phenotype of cancer cells, how the metabolic phenotype supports intrinsic radioresistance by the improved antioxidant defense, and also discuss potential subtype-specific actionable metabolic vulnerabilities. Understanding metabolic phenotypes of radioresistance and metabolic bottlenecks of cancer cells undergoing radiotherapy in a cancer-specific context will offer largely unexploited future avenues for biological individualization and optimization of radiotherapy. Transcriptional profiles will provide additional benefit in defining metabolic phenotypes associated with radioresistance, particularly in cases, where such dependencies cannot be identified by specific somatic mutations.
Short‐term reliability evaluation of integrated electricity and gas systems considering dynamics of gas flow
Authors: Wang Sheng , Ding Yi , Han Xiaoqing , Wang Peng , Goel Lalit , Ma Jien
Published: June 2021

With the adoption of gas‐fired units (GFU), the interaction between the electricity and gas systems has been intensified. The failure of the gas sources may lead to the insufficiency of the gas supply to the GFUs, and further result in the electricity supply shortage, threatening reliabilities of electricity and gas systems. However, compared with the electric power flow, the dynamics of the gas flow are much slower. Most of the existing studies evaluated the reliabilities of integrated electricity and gas systems (IEGS) without considering the slower dynamics of gas flow, which are not fully accurate in the short‐term. This paper proposes a short‐term reliability evaluation technique for IEGS considering the gas flow dynamics. Firstly, the short‐term reliability models of gas sources, GFUs, and gas compressors are developed. Then, the multi‐stage contingency management scheme is proposed, where gas flow dynamics are analysed for determining the time‐varying load curtailments of electricity and gas. Moreover, a time‐sequential Monte Carlo simulation technique is developed with the finite‐difference scheme to tackle the gas flow dynamics during the short‐term reliability evaluation. Finally, the proposed reliability evaluation technique is validated using an integrated IEEE reliability test system and the practical Belgium gas transmission system.
Electric field measurements at the plasma frequency around comet 67P by RPC-MIP on board Rosetta
Authors: Myllys M. , Henri P. , Vallières X. , Gilet N. , Nilsson H. , Palmerio E. , Turc L. , Wellbrock A. , Goldstein R. , Witasse O.
Published: June 2021

Context. The Mutual Impedance Probe (RPC-MIP) carried by the Rosetta spacecraft monitored both the plasma density and the electric field in the close environment of comet 67P/Churyumov–Gerasimenko (67P), as the instrument was operating alternatively in two main modes: active and passive. The active mode is used primarily to perform plasma density measurements, while the passive mode enables the instrument to work as a wave analyzer.

Aims. We are reporting electric field emissions at the plasma frequency near comet 67P observed by RPC-MIP passive mode. The electric field emissions are related to Langmuir waves within the cometary ionized environment. In addition, this study gives feedback on the density measurement capability of RPC-MIP in the presence of cold electrons.

Methods. We studied the occurrence rate of the electric field emissions as well as their dependence on solar wind structures like stream interaction regions (SIRs) and coronal mass ejections (CMEs).

Results. We are showing that strong electric field emissions at the plasma frequency near 67P were present sporadically throughout the period when Rosetta was escorting the comet, without being continuous, as the occurrence rate is reported to be of about 1% of all the measured RPC-MIP passive spectra showing strong electric field emissions. The Langmuir wave activity monitored by RPC-MIP showed measurable enhancements during SIR or CME interactions and near perihelion.

Conclusions. According to our results, Langmuir waves are a common feature at 67P during the passage of SIRs. Comparing the plasma frequency given by the RPC-MIP passive mode during Langmuir wave periods with the RPC-MIP active mode observations, we conclude that the measurement accuracy of RPC-MIP depends on the operational submode when the cold electron component dominates the electron density.
The angular-momentum flux in the solar wind observed during Solar Orbiter’s first orbit
Authors: Verscharen Daniel , Stansby David , Finley Adam J. , Owen Christopher J. , Horbury Timothy , Maksimovic Milan , Velli Marco , Bale Stuart D. , Louarn Philippe , Fedorov Andrei , Bruno Roberto , Livi Stefano , Khotyaintsev Yuri V. , Vecchio Antonio , Lewis Gethyn R. , Anekallu Chandrasekhar , Kelly Christopher W. , Watson Gillian , Kataria Dhiren O. , O’Brien Helen , Evans Vincent , Angelini Virginia ,   the Solar Orbiter SWA, MAG and RPW teams
Published: June 2021

Aims.We present the first measurements of the angular-momentum flux in the solar wind recorded by the Solar Orbiter spacecraft. Our aim is to validate these measurements to support future studies of the Sun’s angular-momentum loss.

Methods.We combined 60-min averages of the proton bulk moments and the magnetic field measured by the Solar Wind Analyser and the magnetometer onboard Solar Orbiter. We calculated the angular-momentum flux per solid-angle element using data from the first orbit of the mission’s cruise phase in 2020. We separated the contributions from protons and from magnetic stresses to the total angular-momentum flux.

Results.The angular-momentum flux varies significantly over time. The particle contribution typically dominates over the magnetic-field contribution during our measurement interval. The total angular-momentum flux shows the largest variation and is typically anti-correlated with the radial solar-wind speed. We identify a compression region, potentially associated with a co-rotating interaction region or a coronal mass ejection, which leads to a significant localised increase in the angular-momentum flux, albeit without a significant increase in the angular momentum per unit mass. We repeated our analysis using the density estimate from the Radio and Plasma Waves instrument. Using this independent method, we find a decrease in the peaks of positive angular-momentum flux, but otherwise, our results remain consistent.

Conclusions.Our results largely agree with previous measurements of the solar wind’s angular-momentum flux in terms of amplitude, variability, and dependence on radial solar-wind bulk speed. Our analysis highlights the potential for more detailed future studies of the solar wind’s angular momentum and its other large-scale properties with data from Solar Orbiter. We emphasise the need for studying the radial evolution and latitudinal dependence of the angular-momentum flux in combination with data from Parker Solar Probe and other assets at heliocentric distances of 1 au and beyond.
Comparison of Acceptance and Knowledge Transfer in Patient Information Before an MRI Exam Administered by Humanoid Robot Versus a Tablet Computer: A Randomized Controlled Study
Authors: Stoevesandt Dietrich , Jahn Patrick , Watzke Stefan , Wohlgemuth Walter A. , Behr Dominik , Buhtz Christian , Faber Irina , Enger Stephanie , Schwarz Karsten , Brill Richard
Published: June 2021

Purpose To investigate whether a humanoid robot in a clinical radiological setting is accepted as a source of information in conversations before MRI examinations of patients. In addition, the usability and the information transfer were compared with a tablet.

Methods Patients were randomly assigned to a robot or tablet group with their consent prior to MRI. The usability of both devices was compared with the extended System Usability Scale (SUS) and the information transfer with a knowledge query. Reasons for refusal were collected by a non-responder questionnaire.

Results At the University Hospital Halle 117 patients were included for participation. There was no statistically significant difference in gender and age. Of 18 non-responders, 4 refused to participate partly because of the robot; for another 3 the reason could not be clarified. The usability according to SUS score was different with statistical significance between the groups in the mean comparison and was one step higher for the tablet on the adjective scale. There was no statistically significant difference in knowledge transfer. On average, 8.41 of 9 questions were answered correctly.

Conclusion This study is the first application, in a clinical radiological setting, of a humanoid robot interacting with patients. Tablet and robot are suitable for information transfer in the context of MRI. In comparison to studies in which the willingness to interact with a robot in the health care sector was investigated, the willingness is significantly higher in the present study. This could be explained by the fact that it was a concrete use case that was understandable to the participants and not a hypothetical scenario. Thus, potentially high acceptance for further specific areas of application of robots in radiology can be assumed. The higher level of usability perceived in the tablet group can be explained by the fact that here the interface represents a form of operation that has been established for years in all population groups. More frequent exposure to robots could also improve the response in the future.

Key Points:

Citation Format
Der Chemokinrezeptor CXCR4 – seine Entwicklung und Bedeutung in der nuklearmedizinischen Theranostik
Authors: Bergner Carina , Gummesson Anja , Joksch Markus , Sarvestani Mohammadreza Kamali , von Helldorff Heike , Lapa Constantin , Krause Bernd J. , Schwarzenböck Sarah M.
Published: June 2021

Der Chemokinrezeptor CXCR4 – häufig nachgewiesen, doch selten greifbar. Während in einer schier endlosen Zahl an Studien seine physiologische und pathogene Präsenz, seine zellulären Funktionen sowie Möglichkeiten seiner gezielten pharmakologischen Kontrolle seit fast 30 Jahren erforscht werden, ist das Spektrum seiner nuklearmedizinischen klinischen Anwendungen mit malignen Krankheitsbildern des hämatopoetischen Systems und einigen wenigen Entzündungsprozessen immer noch überschaubar. Das Verständnis um Prozesse, die seine dynamische Zelloberflächenexpression regulieren sowie die Suche nach selektiven Radiopharmaka zur Unterscheidung physiologischer von pathogenen CXCR4-Expressionen stellen die Herausforderung der Zukunft dar, um den CXCR4 als ein vielseitiges theranostisches Target in der Nuklearmedizin zu manifestieren.
Risk Assessment Models for Thrombosis and Anticoagulant-Related Bleeding in Ambulatory Cancer Patients
Authors: Candeloro Matteo , Guman Noori A.M. , Kraaijpoel Noémie , Di Nisio Marcello
Published: June 2021

Cancer patients have a high risk of developing venous thromboembolism and arterial thrombosis, along with an increased risk of anticoagulant-related bleeding with primary and secondary prophylaxis of cancer-associated thrombosis. Decisions on initiation, dosing, and duration of anticoagulant therapy for prevention and treatment of cancer-associated thrombosis are challenging, as clinicians have to balance patients' individual risk of (recurrent) thrombosis against the risk of bleeding complications. For this purpose, several dedicated risk assessment models for venous thromboembolism in cancer patients have been suggested. However, most of these scores perform poorly and have received limited to no validation. For bleeding and arterial thrombosis, no risk scores have been developed specifically for cancer patients, and treatment decisions remain based on clinical gestalt and rough and unstructured estimation of the risks. The aims of this review are to summarize the characteristics and performance of risk assessment scores for (recurrent) venous thromboembolism and discuss available data on risk assessment for bleeding and arterial thrombosis in the cancer population. This summary can help clinicians in daily practice to make a balanced decision when considering the use of risk assessment models for cancer-associated venous thromboembolism. Future research attempts should aim at improving risk assessment for arterial thrombosis and anticoagulant-related bleeding in cancer patients.
Using nuclear forces to quantify the substituent effect
Authors: Green Leigh Ann
Published: June 2021

Model quantifies the energy variations produced by chemical substitution.
An analytical model of wind-farm blockage
Authors: Segalini A.
Published: June 2021

Wind-farm blockage is investigated by means of an analytical model based on the linearized Reynolds-averaged Navier–Stokes equation. Despite the simplifications, useful insight is obtained about the induction region upstream of a single wind turbine and of a cluster of turbines. Since the model is linearized, superposition methods are allowed and the farm blockage is obtained as a linear superposition of all the induction zones of each turbine present in the farm, including the mirrored ones due to the presence of the ground. The model is validated against data from wind tunnel experiments, and it is later used to assess blockage in velocity and power for wind farms with different layouts and from several wind directions.
Incidence angle and diffuse radiation adaptation of soiling ratio measurements of indirect optical soiling sensors
Authors: Wolfertstetter F. , Esquelli A. , Wilbert S. , Hanrieder N. , Blum N. , Korevaar M. , Bergmans T. , Zarzalejo L. , Polo J. , Alami-Merrouni A. , Ghennioui A.
Published: June 2021

Soiling is responsible for a loss of 3%–4% of the potential global solar power production that is estimated to rise because of increased deployment in dusty environments [Ilse et al., Joule 3, 2303–2321 (2019)]. For effective mitigation strategies and site selection soiling ratio data is crucial. Soiling can be measured directly by comparing the power or short circuit current of a soiled PV cell or module to that of a clean photovoltaic (PV) device of the same model. In recent years, a number of indirect soiling sensors such as Kipp and Zonen's DustIQ and Atonometric's MARS were introduced. These sensors do not use PV cells to determine the soiling ratio. Indirect soiling sensors derive soiling based on information such as particle concentration and size. The soiling loss of PV systems shows a strong angle of incidence (AOI) dependent pattern for sunny conditions. This pattern is not reproduced by indirect sensors such as DustIQ and MARS. We developed a method to adapt the soiling measurement of indirect soiling sensors using the AOI and the Linke turbidity. The adaptation is based on an analysis of the AOI dependence of the reference cell-derived soiling ratio. Linke turbidity is derived from irradiance measurements. The method reduces the root mean square error between the soiling ratios detected by the DustIQ and a colocated pair of PV reference cells from 0.7% to 0.2%. It can improve cumulative performance calculations that use indirect soiling measurements as an input.
Transformations to amorphous and X-type phases in swift heavy ion-irradiated Ln2O3 and Mn2O3
Authors: Solomon Alexandre P. , Tracy Cameron L. , O’Quinn Eric C. , Severin Daniel , Lang Maik K.
Published: June 2021

The intense, highly localized electronic excitation resulting from swift heavy ion irradiation induces phase transformations in many materials including lanthanide sesquioxides (Ln2O3). To explore the effects of chemical composition on radiation-induced transformations, the structural responses of several related sesquioxides to swift heavy ion irradiation were compared. Polycrystalline Nd2O3, Eu2O3, Yb2O3, and Mn2O3 were irradiated by 946 MeV Au ions to a range of ion fluences up to 2 × 1013 cm−2, and structural modifications were characterized using beamline-based in situ x-ray diffraction and Rietveld refinement. Amorphization was induced in Nd2O3, Eu2O3, and Mn2O3 with the extent of induced transformation following a clear dependence on cation ionic radius. Nd2O3 and Eu2O3, having the largest cations, were rapidly amorphized, whereas Mn2O3, having the smallest cation, experienced only a slight loss of crystallinity at the highest fluences studied. The radiation response was different for Yb2O3, which underwent a sluggish transformation to a nonequilibrium X-type phase. The crystalline-to-amorphous transformations were proceeded by direct-impact mechanisms, while the C-to-X transformation was proceeded by a multi-impact mechanism.
Variational determination of ground and excited-state two-electron reduced density matrices in the doubly occupied configuration space: A dispersion operator approach
Authors: Alcoba Diego R. , Oña Ofelia B. , Lain Luis , Torre Alicia , Capuzzi Pablo , Massaccesi Gustavo E. , Ríos Elías , Rubio-García Alvaro , Dukelsky Jorge
Published: June 2021

This work implements a variational determination of the elements of two-electron reduced density matrices corresponding to the ground and excited states of N-electron interacting systems based on the dispersion operator technique. The procedure extends the previously reported proposal [Nakata et al., J. Chem. Phys. 125, 244109 (2006)] to two-particle interaction Hamiltonians and N-representability conditions for the two-, three-, and four-particle reduced density matrices in the doubly occupied configuration interaction space. The treatment has been applied to describe electronic spectra using two benchmark exactly solvable pairing models: reduced Bardeen–Cooper–Schrieffer and Richardson–Gaudin–Kitaev Hamiltonians. The dispersion operator combined with N-representability conditions up to the four-particle reduced density matrices provides excellent results.
Performance of vertical type deep UV light-emitting diodes depending on the Ga-face n-contact hole density
Authors: Sung Youn Joon , Kim Dong-Woo , Yeom Geun Young , Kim Kyu Sang
Published: June 2021

We have demonstrated a vertical UV-C LED composed of the Ga-face n-contact electrodes using the circular shape holes on mesa. In order to understand the dependence of optical performance on the mesa hole density, we varied the number of holes. As the number of holes on mesa increased, both the light output power and the external quantum efficiency of vertical chips have enhanced while preserving the operation voltage. In spite of reduced active area, the efficiency of current injection could be improved by reducing the current density per hole. The increased mesa hole density of vertical chips induces the enhanced light extraction through the sidewall of holes.
Synchrotron studies of functional interfaces and the state of the art: A perspective
Authors: Yan Xi , Fong Dillon D. , Zhou Hua , McChesney Jessica L.
Published: June 2021

The dramatic improvements in synchrotron light sources across the world imply tremendous opportunities for interface science. In this Perspective, we describe a variety of current scattering and spectroscopic techniques with an eye toward how these will evolve, particularly with the advent of diffraction-limited sources. We also note the importance of in situ and operando methods for both understanding interface creation and interface evolution in different environments. As interfaces are often where critical processes occur, whether in regard to energy/chemical/materials/quantum information science, understanding the utility of these x-ray techniques will be of considerable importance to the cultivation of next-generation scientists.
Influence of solution phase environmental heterogeneity and fluctuations on vibronic spectra: Perylene diimide molecular chromophore complexes in solution
Authors: Kumar Manav , Provazza Justin , Coker David F.
Published: June 2021

Ensembles of ab initio parameterized Frenkel-exciton model Hamiltonians for different perylene diimide dimer systems are used, together with various dissipative quantum dynamics approaches, to study the influence of the solvation environment and fluctuations in chromophore relative orientation and packing on the vibronic spectra of two different dimer systems: a π-stacked dimer in aqueous solution in which the relative chromophore geometry is strongly confined by a phosphate bridge and a side-by-side dimer in dichloromethane involving a more flexible alkyne bridge that allows quasi-free rotation of the chromophores relative to one another. These entirely first-principles calculations are found to accurately reproduce the main features of the experimental absorption spectra, providing a detailed mechanistic understanding of how the structural fluctuations and environmental interactions influence the vibronic dynamics and spectroscopy of solutions of these multi-chromophore complexes.
The relative order of foci and polarity complementizers
Authors: Callegari Elena
Published: June 2021

According toRizzi & Bocci’s (2017)suggested hierarchy of the left periphery, fronted foci (FOC) can never precede polarity complementizers (PolC); yet languages like Bulgarian and Macedonian appear to display precisely such an ordering configuration. On the basis of a cross-linguistic comparison of ten Slavic languages, I argue that in the Slavic subgroup the possibility of having a focus precede PolC is dependent on the morphological properties of the complementizer itself: in languages where the order FOC < PolC is acceptable, PolC is a complex morpheme derived through the incorporation of a lower functional head with a higher one. The order FOC < PolC is then derived by giving overt spell-out to the intermediate copy of PolC rather than to the topmost one. In turn, this option is linked to the possibility, recorded in all languages which allow for FOC < PolC, to also realize the morpheme expressing interrogative polarity as an enclitic particle attaching to fronted foci.
Assessment of muscle volume using magnetic resonance imaging (MRI) in football players after hamstring injuries
Authors: Mühlenfeld Nils , Steendahl Ida Bo , Berthold Daniel P. , Meyer Tim , Hauser Thomas , Wagner Nils , Sander Anna‐Lena , Marzi Ingo , Kaltenbach Benjamin , Yel Ibrahim , Vogl Thomas , Eichler Katrin
Published: June 2021

Muscle injuries of the hamstrings are among the most frequent in football and a main cause for significant time away from training and competition. The purpose of this study was to prospectively evaluate the loss of muscle volume in recreational football players three and six weeks after initial trauma. We hypothesized that significant muscle volume loss occurs within 6 weeks after the initial injury event. Twenty recreational football players (mean‐age=25 ± 4years; mean‐height=181 ± 8cm; mean‐weight=81 ± 10kg) with type3a (minor partial muscle tear) and type3b (moderate partial muscle tear) injuries were included. Muscle volume was determined using established methods for the hamstrings and the quadriceps femoris muscle within 3 days and after 3 and 6 weeks following the initial injury. The injured hamstrings lost 6.5% (mean=64 cm3(95%CI=31–98 cm3), p<0.001), the healthy hamstrings lost 2.1% (mean=21 cm3(3–44 cm3),p=0.096) of muscle volume after six weeks. The quadriceps in the injured leg lost 3.8% (mean=78 cm3(51–104 cm3), p<0.001) and 4.5% (83 cm3 (45–121 cm3), p<0.001) in the healthy leg. Muscle volume loss inversely correlated with activity levels in the healthy leg for the quadriceps (r=0.96 (0.90–0.98); R 2=0.92; p<0.001) and the hamstrings (r=0.72 (0.40–0.88); R 2=0.51; p<0.001), as well as the quadriceps in the injured leg (r=0.70 (0.37–0.87); R 2=0.49; p<0.001), but not the injured hamstrings. Muscle volume ratio of hamstrings to quadriceps in the control limb was 0.52 ± 0.06 and 0.53 ± 0.06 in the injured leg. The rehabilitation period of six weeks did not have a relevant negative or a positive effect on ratios. Significant muscle volume loss in the upper thigh occurs in recreational soccer players within three, and within six weeks after a hamstring injury and lies between 2% and 7%.
Tip-induced
β
-hydrogen dissociation in an alkyl group bound on Si(001)
Authors: Adamkiewicz A , Bohamud T , Reutzel M , Höfer U , Dürr M
Published: June 2021

Atomic-scale chemical modification of surface-adsorbed ethyl groups on Si(001) was induced and studied by means of scanning tunneling microscopy. Tunneling at sample bias >+1.5 V leads to tip-induced C–H cleavage of a β-hydrogen of the covalently bound ethyl configuration. The reaction is characterized by the formation of an additional Si–H and a Si–C bond. The reaction probability shows a linear dependence on the tunneling current at 300 K; the reaction is largely suppressed at 50 K. The observed tip-induced surface reaction at room temperature is thus attributed to a one-electron excitation in combination with thermal activation.
3.3 kV 4H-SiC DMOSFET with a source-contacted dummy gate for high-frequency applications
Authors: Cha Kyuhyun , Kim Kwangsoo
Published: June 2021

In this paper, a 4H-SiC DMOSFET with a source-contacted dummy gate (DG-MOSFET) is proposed and analyzed through Sentaurus TCAD and PSIM simulations. The source-contacted MOS structure forms fewer depletion regions than the PN junction. Therefore, the overlapping region between the gate and the drain can be significantly reduced while limiting R
ON degradation. As a result, the DG-MOSFET offers an improved high-frequency figure of merit (HF-FOM) over the conventional DMOSFET (C-MOSFET) and central-implant MOSFET (CI-MOSFET). The HF-FOM (R
ON×Q
GD) of the DG-MOSFET was improved by 59.2% and 22.2% compared with those of the C-MOSFET and CI-MOSFET, respectively. In a double-pulse test, the DG-MOSFET could save total power losses of 53.4% and 5.51%, respectively. Moreover, in a power circuit simulation, the switching power loss was reduced by 61.9% and 12.7% in a buck converter and 61% and 9.6% in a boost converter.
Experimental study on scour characteristics of the sheet-pile groin
Authors: Yang Yuanping , Zhang Zhiyong , He Kun , Chen Gang
Published: June 2021

Spur dike is widely used to protect river bank in hydraulic engineering. However, the scour around spur dike caused by narrowing flow is often too deep to induce the failure of dike. In this paper, a new type of spur dike: sheet-pile groin is developed and the scour characteristics around it are studied based on experiment. The experiment results show that, compared with the solid spur dike of the same size, the maximum scour depth near the head of the sheet-pile groin reduces by averagely 30% under the same flow conditions. The sheet-pile groin makes the water flow away from itself and the shoreline. When there is an over-dam flow on the top of the spur dike, the sheet-pile groin has a stronger protective effect on the beach behind it than the solid spur dike does. The scouring and silting features of the local riverbed around the sheet-pile groin benefit the stability of the spur dike and the protection of the coastal beaches.
Study on performance of new type cold mix epoxy asphalt and mixture for steel deck pavement
Authors: Shao Wei-Xian , Zhou Bin-Jie
Published: June 2021

In order to improve the performance of steel bridge deck pavement material, improve the construction efficiency and reduce the cost of steel bridge deck pavement, this paper introduces a new type of cold mixed epoxy asphalt, and studies the mechanical properties and curing law of the material through Marshall test. The results show that it has good mechanical properties, and the curing days at room temperature are 2-3 days. Based on the test data, compared with the United States and Japan, this paper analyzes the remarkable characteristics of the cold mix epoxy asphalt, which has the advantages of normal temperature construction, long retention time, good operability, low construction cost, less curing days, early opening of traffic, low material cost and reducing energy consumption. If it is used as the paving material for steel bridge deck, it has a broad application prospect.
Analysis of the influence of key parameters of UHPC-annular reinforcement wet joint
Authors: Shao Changfei , Qin Kaiqiang , Xiao Wei
Published: June 2021

Based on the connection line reconstruction project of Shanghai Road High-speed Railway Station in Suqian City, this paper carried out the impact analysis of the key parameters of UHPC-circular steel bar wet joints, including the influence of steel bar arrangement spacing, steel bar diameter, and wet joint width on the mechanical properties of the joints. From the research results, the steel bar diameter, the steel bar spacing and the width of the wet joint have an impact on the load-bearing capacity performance and normal use performance of the joint structure, but the degree and regularity of the impact are not consistent, and the reinforcement ratio increases. Larger and the increase of the width of the wet joint has a more obvious contribution to the improvement of the ultimate state of the load-bearing capacity of the UHPC-annular steel wet joint, but it has a small impact on the normal use performance. Therefore, the actual design should proceed from the actual project, comprehensively consider the carrying capacity and normal use requirements and rationally design each parameter.
Preparation and Performance Evaluation of an Environmentally Friendly Lubricant for Water-based Drilling fluid
Authors: Shan Kai , Qiu Zhengsong , Zhang Wei , Zhong Hanyi , Zhao Xin , Di Mingli , Mo Jian
Published: June 2021

With the increasing difficulty of exploration and development of oil and gas resources, the problems of high friction torque in long horizontal well section and high temperature in deep well are increasingly prominent, which put forward higher technical requirements for the lubricity, temperature resistance and environmental protection of drilling fluid lubricant. Traditional drilling fluid lubricants are difficult to meet the above technical requirements. Based on the optimization of modified vegetable oil, extreme pressure agent, surfactant, antioxidant and preparation conditions, an environmentally friendly drilling fluid lubricant SDGL-2 was developed. The evaluation results show that the lubricant SDGL-2 has fluorescence grade of 1~2, temperature resistance of 160 °C, good biodegradability and no toxicity. Its lubricity is better than that of common drilling fluid lubricants, and it is compatible with several common drilling fluids.
Study on the effect of fineness and dosage of fly ash on mechanical properties of concrete
Authors: Wang Qun
Published: June 2021

Ultrafine fly ash concrete is one of the main directions for the development of concrete materials in the future. In order to study the mechanical properties of ultra-fine fly ash concrete, the compressive strength, splitting tensile strength and flexural strength of concrete under different ages and different ultra-fine fly ash particle sizes and dosages were tested. (1) The slump of concrete mix under different fly ash particle size increases with the increase of ultrafine fly ash content, but the rate of increase decreases gradually. Under the same fly ash content, the smaller the particle size of ultrafine fly ash particles, the greater the slump of the corresponding fly ash concrete, and it has the exponential relationship between the particle size and the particle size of fly ash. (2) The smaller the particle size of ultra-fine fly ash, the larger the optimum dosage in concrete. When the particle size of ultrafine fly ash is less than 5μm, the optimal dosage of ultrafine fly ash in concrete is 30% to ensure 60d compressive strength. (3) When the concrete curing age is 60d, the splitting tensile strength and flexural strength of ultra-fine fly ash concrete under different particle sizes increase first and then decrease with the increase of ultrafine fly ash content. The law of variation is that the split tensile strength and flexural strength of fly ash concrete are the highest when the content of ultrafine fly ash is 20%-30%.
Experimental study on performance of fiber concrete under simulated acid rain environment
Authors: Ma Anjing , Li Zhenshu , Feng Xiangrui
Published: June 2021

This experiment studies the influence of different fiber content on the mechanical properties of concrete under simulated acid rain environment (pH=2.5) in the laboratory. Under the action of acid rain erosion, the total content of carbon fiber and basalt fiber are respectively 0.1%, 0.2%, and 0.3%, of which carbon fiber and basalt fiber each account for 50% of the total content. The experiment adopts the cycle immersion method to study the laboratory to simulate acid rain to accelerate the corrosion of concrete. After simulating acid rain corrosion for 25 days, it is naturally dried for 5 days. The compressive strength and splitting tensile strength are measured. The comparison shows that when the total fiber content is 0.2%, the concrete the tensile-compression ratio of the test block is the largest, and its splitting tensile strength increases by 15.09% as the maximum.