bluuebunny/crossref_metadata_2025 huggingface dataset:
Simultaneous quantitation of kavalactones in kava dry extracts: comparison of multi‐standards and single standard validation approaches
Authors: Ferreira Juliana Veloso , Pierotte Isabella Campolina , Pianetti Gerson Antônio , César Isabela Costa
Published: December 2020

Introduction

Dried extracts of Piper methysticum G. Forst, also known as kava, has been widely used due to its anxiolytic and sedative properties. In order to assure the quality of these extracts, it is essential to accurately quantify kavalactones, known as the active principle.

Objectives

To develop and validate an analytical method for the simultaneous quantification of six major kavalactones (kavain, dihydrokavain, methysticin, dihydromethysticin, yangonin and demethoxyyangonin) in kava extracts, comparing multi‐standards and single standard validation approaches.

Material and methods

Separation was performed using a C18 column, water/methanol/acetonitrile/2‐propanol (66:07:09:18 v/v/v/v) and detection at 245 and 350 nm. A full method validation was performed, employing analytical standards for each compound. Commercial kava dried extracts were assayed and the results obtained using the method validated for six kavalactone standards were compared with those obtained when only kavain was used as standard.

Results

Baseline resolution for all kavalactones was obtained in short run time (15 min). Although the total kavalactone content varied between samples, a similar distribution profile was observed. When the method validated with all six analytical standards was compared to the calibration using only kavain standard, kavalactone contents were considerably different (from 7.57 to 36.53%).

Conclusion

The obtained results demonstrate the importance of a validated method using individual kavalactone standards for the effective quality control of kava extracts. In a next step, the method needs to be adapted to also include flavokavin B (FKB), as an important authentication marker to distinguish between the accepted variety “noble Kava” and the toxic “two‐day Kava”.
Comparing teacher stress in Chinese and US elementary schools: Classroom appraisal of resources and demands
Authors: Wang Chuang , Zhang Juan , Lambert Richard G. , Wu Chenggang , Wen Hongbo
Published: December 2020

Based on Messick's (1995) framework of construct validity and responses from 521 teachers in the United States and 580 teachers in China, this study provided evidence of the generalizability aspect of construct validity for the Classroom Appraisal of Resources and Demands (CARD) questionnaire originally developed in the United States. Confirmatory factor analysis, factorial invariance testing, and differential item functioning were employed to examine the systematic variation of interpretation by the Chinese and US elementary school teachers with respect to the 65 items in the CARD. Results suggested that responses to CARD follow the same structure from both Chinese and US teachers, and that 83% of items showed no difference. Differences in Chinese and US teachers' interpretations of certain items were discussed with implications to school psychology, school counseling, teacher education, educational administration, and policy research.
Copolymers of 4‐thieno[3,2‐b]thiophen‐3‐ylbenzonitrile with anthracene and biphenyl; synthesis, characterization, electronic, optical, and thermal properties
Authors: Isci Recep , Gunturkun Dilara , Yalin Ahsen Sare , Ozturk Turan
Published: December 2020

Two novel copolymers of 4‐thieno[3,2‐b]thiophen‐3‐ylbenzonitrile (TT‐CN), possessing electron withdrawing cyano moiety, with anthracene (P1) and biphenyl (P2) were prepared via Suzuki coupling. Optic, electronic, and thermal properties of the copolymers were investigated through UV–Vis spectroscopy, cyclic voltammetry, gel permeation chromatography, and thermal gravimetric analysis. The polymers with anthracene and biphenyl had electronic band gaps of 2.01 and 1.90 eV, respectively. Both polymers demonstrated excellent large Stokes shifts of 101 (anthracene) and 105 nm (biphenyl) as well as very good thermal properties. As they had good optical, electronic, and thermal properties, they are promising candidates for electronic applications.
Natural compound catechol induces DNA damage, apoptosis, and G1 cell cycle arrest in breast cancer cells
Authors: Vazhappilly Cijo George , Hodeify Rawad , Siddiqui Shoib Sarwar , Laham Amina Jamal , Menon Varsha , El‐Awady Raafat , Matar Rachel , Merheb Maxime , Marton John , Al Zouabi Hussain Abdel Karim , Radhakrishnan Rajan
Published: December 2020

Targeting cell cycle and inducing DNA damage by activating cell death pathways are considered as effective therapeutic strategy for combating breast cancer progression. Many of the naturally known small molecules target these signaling pathways and are effective against resistant and/or aggressive types of breast cancers. Here, we investigated the effect of catechol, a naturally occurring plant compound, for its specificity and chemotherapeutic efficacies in breast cancer (MCF‐7 and MDA‐MB‐231) cells. Catechol treatment showed concentration‐dependent cytotoxicity and antiproliferative growth in both MCF‐7 and MDA‐MB‐231 cells while sparing minimal effects on noncancerous (F‐180 and HK2) cells. Catechol modulated differential DNA damage effects by activating ATM/ATR pathways and showed enhanced γ–H2AX expression, as an indicator for DNA double‐stranded breaks. MCF‐7 cells showed G1 cell cycle arrest by regulating p21‐mediated cyclin E/Cdk2 inhibition. Furthermore, activation of p53 triggered a caspase‐mediated cell death mechanism by inhibiting regulatory proteins such as DNMT1, p‐BRCA1, MCL‐1, and PDCD6 with an increased Bax/Bcl‐2 ratio. Overall, our results showed that catechol possesses favorable safety profile for noncancerous cells while specifically targeting multiple signaling cascades to inhibit proliferation in breast cancer cells.
Fuzzy multiobjective system reliability optimization by genetic algorithms and clustering analysis
Authors: Chebouba Billal Nazim , Mellal Mohamed Arezki , Adjerid Smail
Published: December 2020

System reliability optimization is a key element for a competitive and safe industrial plant. This paper addresses the multiobjective system reliability optimization in the presence of fuzzy data. A framework solution approach is proposed and based on four steps: defuzzify the data into crisp values by the ranking function procedure, the defuzzified problems are solved by the non‐sorting genetic algorithms II and III (NSGA‐II and NSGA‐III), the Pareto fronts are compared by the spacing method for selecting the best one, and then the best Pareto front is reduced by the clustering analysis for helping the decision maker. A case study presented in the literature as a mono‐objective redundancy allocation problem with fuzzy data is investigated in the present paper as multiobjective redundancy allocation and reliability‐redundancy allocation problems show the applicability of the approach.
Further studies on state estimation of discrete‐time nonlinear parameter varying systems based on a new multiinstant switching observer
Authors: Zhou Xia , Xie Xiang‐Peng , Yue Dong , Chadli Mohammed
Published: December 2020

This article is concerned with further studies on state estimation of discrete‐time nonlinear parameter varying systems with the help of an efficient multiinstant switching observer. First, a pair of variable weights for different sampling instants are introduced and thus more featured switching modes for the applied observer are produced by updating and utilizing all the varying elements that vary upon time. Second, an individual designing condition of the developed multiinstant switching observer for each switching mode is derived by considering the specific information of the updated varying elements, respectively. Indeed, the whole obtained result is less conservative than the previous ones. Finally, some comparative simulations are provided in order to illustrate the advantage and benefit of the developed results.
Observer‐based preview repetitive control for uncertain discrete‐time systems
Authors: Li Li
Published: December 2020

In this paper, the preview repetitive control (PRC) problem is considered for uncertain discrete‐time systems subject to a previewable periodic reference signal. First, an augmented system including future information on the previewable reference signal is constructed. Second, considering the state unmeasured and periodic tracking reference signal, state observer and preview repetitive controller (PRCr) are designed in both state feedback and output feedback settings. To achieve signal tracking performance, a two‐dimensional (2D) model approach and some LMI technique are presented to describe the control and learning actions of the PRC system by using the lifting technique. Then, by Lyapunov–Krasovskii functions, sufficient conditions for asymptotic stability of the 2D system are derived in the form of a set of LMIs, and meanwhile, the design of a repetitive controller with preview actions is proposed through the LMI approach. Finally, two examples illustrate the effectiveness of the results.
Influence of coarse‐textured soil layers under crop root zone on soil water and salt dynamics and crop yield in shallow groundwater areas
Authors: Chen Shuai , Mao Xiaomin , Shukla Manoj K.
Published: December 2020

Coarse‐textured soil layers under crop root zone could modify soil water and salt dynamics and affect crop growth. However, the influence is not thoroughly investigated, especially under shallow groundwater table and soil salinization conditions. For this purpose, we calibrated and validated a one‐dimensional agro‐hydrological model, LAWSTAC, for soil water and salt movement, and their interactions with maize growth in Northwest China. Simulation results fitted well with the measured values of soil water content, salt concentration, leaf area index, and crop yield for the maize growing seasons of 2012 and 2013. Further simulations were conducted to evaluate the influence of buried depths (80, 90, 100, and 110 cm) and thicknesses (10, 20, 30, 40, and 50 cm) of a coarse sand layer under root zone on soil water storage, salt leaching, and crop yield. Results demonstrated that soil water and salt status in the root zone was related to the water content of the coarse‐textured soil layer. Water percolation increased rapidly when water content in the coarse layer was higher than a critical value, which could be beneficial for salt leaching but unfavorable for water retention in the root zone. These results could help understand the influence of the coarse‐textured soil layer on root zone water storage and salt leaching and provide guidance on the irrigation scheduling for salt leaching and crop growth in areas with salinization problems and shallow groundwater tables.
A Highly Active Catalyst 2,4,6‐Tris (di‐4‐chlorobenzamido)‐1,3,5‐triazine Palladium (II) Chloride for the Green Synthesis of Substituted Dihydrobenzo[b]thiophene in Ionic Liquid
Authors: Sayedul Islam Md. , Abu Sayid Mia Md.
Published: December 2020

The palladium‐metallodendrimer (Pd‐MD) 2,4,6‐tris (di‐4‐chlorobenzamido)‐1,3,5‐triazine palladium (II) chloride was synthesized by the reaction of substituted triazine, substituted benzoyl chloride, and (Ph3P)2PdCl2 in DMF at 100 °C. This Pd‐MD was characterized by FTIR, 1H NMR, 13C NMR, Scanning Electron Microscopy (SEM), Energy Dispersive X‐ray (EDX), mass spectrometry, X‐ray photoelectron spectroscopy (XPS), elemental analysis, Thermogravimetric analysis (TGA), and Differential scanning calorimetry (DSC) methods. This catalyst was successfully applied for the green synthesis of different substituted alkyl 2,3‐dihydrobenzo[b]thiophene‐2‐carboxylates in ionic liquid tetra‐n‐butylammonium bromide (TBAB) solution at 120 °C for 2.5 hours with a good to an excellent percentage of yields (75 % to 96 %). Importantly, this homogeneous catalytic system was easily recoverable and reusable at least five times without a significant loss of activity.
Microwave‐assisted Synthesis of CuCl‐MIL‐47 and Application to Adsorptive Denitrogenation of Model Fuel: Response Surface Methodology
Authors: Bereyhi Mohammad , Zare‐Dorabei Rouholah , Mosavi Seyed Hossein
Published: December 2020

Today, energy‐environment concerns are crucial for humans. Environmental pollution will increase as a result of expanding the use of fossil fuels, nitrogen‐containing compounds (NCCs) of which cause destructive effects on the environment. In this study, adsorptive denitrogenation (ADN) was performed by adsorbing indole (IND) from model fuels and gasoline over Metal‐organic frameworks (MOFs) CuCl‐MIL‐47. The MIL‐47 was synthesized by the microwave method with modified CuCl. In the present study, the application of Central Composite Design (CCD) was evaluated in the ADN process optimization for the first time. The maximum adsorption capacity (Q0) CuCl‐MIL‐47 for indole (IND) was 769.2 mg/g. Herein, π‐complexation of IND with Cu has made a synergistic effect leading to an increase in Q0. Moreover, the reusability of CuCl‐MIL‐47 was confirmed through its regeneration via ethanol.
Environmentally Benign One‐pot Synthesis of Benzo‐Fused Seven‐Membered Heterocyclic Compounds Using UiO‐66 Metal‐Organic Framework as Efficient and Reusable Catalyst
Authors: Mirhosseini‐Eshkevari Boshra , Zamani Farzad , Ghasemzadeh Mohammad Ali
Published: December 2020

A series of biologically relevant 1,4‐benzoxazepine and 1,4‐benzodiazepine derivatives were synthesized via a one‐pot three‐component reaction of 2‐aminophenol or ortho‐phenylenediamine, dimedone, and aromatic aldehydes catalyzed by UiO‐66 metal‐organic framework (MOF). This methodology provides excellent yields, simple procedure, short reaction time, low‐cost catalyst, and mild reaction conditions. The UiO‐66 MOF, which was characterized by different spectroscopic techniques such as XRD, FT‐IR, and TEM, could be recovered and reused up to eight times with no significant loss of catalytic performance.
Knowledge governance maturity assessment can help software engineers during the design of business digitalization projects
Authors: Sanchez‐Segura Maria‐Isabel , Medina‐Dominguez Fuensanta , de Amescua Antonio , Dugarte‐Peña German‐Lenin
Published: December 2020

Software engineers and IT professionals face the challenge of envisioning the needs and wishes of their client companies, whose long‐term survivability depends on their adaptability to the digital business ecosystem, which is impregnating more or less every single sector of the economy. Looking at the data reported on the business digitalization project success rate, we realize that there is a lot of room for improvement. In this paper, we focus on the results of developing 10 business digitalization projects for 10 small and medium enterprises, where the software engineers in charge of the projects assessed the knowledge governance maturity of client companies before proposing any specific projects to support their digital businesses. We surveyed the software engineers participating in the above projects to gather their impressions of using knowledge governance assessment as a tool to predictively visualize the digital solution that best fits each digitalization project.
Numerical investigation of the punching shear capacity of unbonded post‐tensioned concrete flat slabs
Authors: Díaz Rafael Sanabria , Trautwein Leandro Mouta , de Almeida Luiz Carlos
Published: December 2020

This paper describes a numerical study of the punching shear resistance of unbonded post‐tensioned slabs without shear reinforcement. This research aimed to develop a methodology for modeling unbonded tendons and numerically evaluate the prestressing effects on the punching shear capacity. To validate the modeling approach, a series of well documented experimental tests were simulated using the finite element software DIANA. The nonlinear analyses were performed using three‐dimensional solid elements, incorporating the cracking behavior of concrete by the smeared crack approach. In addition, interface elements were included, providing bond‐slip properties to simulate the friction between tendons and concrete. A good agreement was found between the numerical results and experimental data. Load capacity, cracks patterns, and the prestressing effects were accurately simulated. After the validation, a parametric study was conducted to analyze the influence of distribution, force and profile of prestressing tendons. Finally, the numerical results were compared with current design code provisions and the approach provided by the Critical Shear Crack Theory.
Experimental study of permeability and elastic modulus of plastic concrete containing nano silica
Authors: Farajzadehha Soroush , Mahdikhani Mahdi , Ziaei Moayed Reza , Farajzadehha Soheil
Published: December 2020

Cut off walls are used under dams for the control of sub surfaces seepage and permeability of cut off wall was important. In the construction of cut off walls, plastic concrete is used and the amount of plastic concrete permeability is important. In this study, the permeability of plastic concrete was investigated and the effect of replacing nano silica instead of cement to reduce permeability was studied. So in this research, compressive strength, elastic modulus, and permeability parameters of plastic concrete specimens at different ages (7, 14, 28, and 56 days) and with different percentages of nano silica (0, 1.5, 3, 4.5, and 6%) were investigated. Also, scanning electron microscopy was used to investigate the effect of nano silica on plastic concrete specimens. The results show that as the age of the specimens increases, the compressive strength and elastic modulus increase, and the permeability of the plastic concrete decreases. Also, by adding nano silica to plastic concrete, the compressive strength of the plastic concrete increases and the plastic concrete permeability decreases significantly while its elastic modulus is almost constant.
Alleviation of cadmium and lead stress by A‐mycorrhizal fungi and rock phosphate on maize (Zea mays L.) growth under calcareous soil conditions
Authors: Abou El Seoud I. I. , Abo Bakr E. M.
Published: December 2020

This research was carried out to investigate the impact of A‐mycorrhizal fungi (AMF) and rock phosphate (RP) (alone and combined) under polluted soil with lead (Pb) and cadmium (Cd) on maize plant growth and soil nutrients availability under calcareous soil conditions. A greenhouse pot experiment was designed as a two‐factor experiment, remediation sources (RS) as the sub‐main factor with four treatments [control, M (mixed of the two mycorrhizae species,Rhizoglomus irregulareandRhizoglomus macrocarpium), RP, and M + RP], and soil pollution sources (PS) as the main factor with nine treatments [control, Pb1 (100 mg Pb /kg soil), Pb2 (500 mg Pb/kg soil), Cd1 (6 mg Cd/kg soil), Cd2 (24 mg Cd/kg soil), Pb1 + Cd1, Pb1 + Cd2, Pb2 + Cd1, Pb2 + Cd2]. The results showed that, under the same conditions of this study, we can recommend the use of coapplication of AMF and RP (M + RP) particularly in contaminated soil with Pb and/or Cd, which supports plants to (i) confront the pollution stress, (ii) improve plants growth and their nutrients content, and (iii) increase the soil available nutrients. Also, maize plants could be labeled as the accumulator of Pb based on (translocation factor > 1) as control and under calcareous soil conditions.
Einleitung
Authors: Reuter Britta
Published: December 2020

Öffentliche Diskussionen und Demonstrationen wegen verschobener, nicht gewollter oder zu teurer Projekte belegen, dass die Steuerzahler einen transparenten Einsatz der von ihnen erwirtschafteten Steuermittel verlangen. Eine wesentliche Rolle für die Transparenz spielen die vorhandenen Verwaltungsdaten, deren volkswirtschaftliches Potential durch mehrere Untersuchungen aufgezeigt wird. Der öffentliche Einkauf beträgt in Europa im Durchschnitt jährlich etwa 15 % des BIP. Das sind für Deutschland etwa 300–400 Milliarden Euro jährlich. Könnten nur 5 % der geschätzten Ausgaben eingespart werden, entsprächen dies 12,5 Milliarden Euro jährlich. Während der Oberschwellenbereich aufgrund von EU-weiten Ausschreibungsverpflichtungen höheren Transparenzanforderungen genügen muss, ist der Unterschwellenbereich weitgehend intransparent. Der Einsatz von Technologie kann hier eine Brücke schlagen und einen weiteren Beitrag zur Transparenz im öffentlichen Einkauf leisten. Die hiermit verbundenen Potentiale, aber auch Risiken, sollen in dieser Arbeit dargelegt werden.
Die Technikfolgenabschätzung als theoretischer Rahmen
Authors: Reuter Britta
Published: December 2020

Die Technikfolgenabschätzung (TFA) bietet den theoretischen Bezugsrahmen, in den diese Arbeit eingebettet wird. Zum besseren Verständnis der Anwendung in vorliegender Arbeit wird die TFA hier ausführlich erläutert. Im weiteren Verlauf der Arbeit wird die mögliche Öffnung der Daten des öffentlichen Einkaufs mithilfe der Wirkungsdimensionen Strategie, Organisation, Recht, Technologie, Transparenz, Kollaboration und Partizipation untersucht. Diese Dimensionen finden in allen verwendeten Methoden Berücksichtigung. Die Diskussion des Themas anhand der TFA soll erleichtern, die verschiedenen Perspektiven zu analysieren und hieraus abschließend ein Leitbild mit Handlungsempfehlungen zu erstellen.
Kontext des öffentlichen Einkaufs
Authors: Reuter Britta
Published: December 2020

In Kapitel 5 werden die für die vorliegende Arbeit wesentlichen Begriffe, Akteure, Ziele und Haltungen, die im Zusammenhang mit öffentlichem Einkauf eine Rolle spielen, erläutert. Zu den wesentlichen Akteuren zählen die Wirtschaft, Politik, Verwaltung, Bürger, NGOs, Medien und Wissenschaft. Die Potentiale der Transparenz, ihre Stärken und Chancen, aber auch Schwächen und Risiken werden jeweils dargelegt. Haltungen zur Öffnung der Verwaltungsdaten im Allgemeinen und Einkaufsdaten im Besonderen werden über die internationalen und europäischen Regierungsprogramme adressiert, aber auch durch IGOs und NGOs aufgegriffen.
Online-Befragung „Offenes öffentliches Beschaffungswesen“
Authors: Reuter Britta
Published: December 2020

Die in den vorherigen Kapiteln theoretisch erörterten und anhand von Beispielen illustrierten Aspekte gilt es Kapitel 8 – aus der Perspektive von Führungskräften und Experten – mithilfe einer Online-Befragung zu überprüfen. Ziel der empirischen Studie ist die Bewertung der Möglichkeiten und Grenzen einer Öffnung von öffentlichen Einkaufsdaten. Die Sichtweisen aus der Verwaltungs- und Wirtschaftsinformatik, den Wirtschafts-, Rechts-, Sozial- und Politikwissenschaften werden interdisziplinär berücksichtigt. Die Ergebnisse sollen zudem eine Brücke zwischen dem Status quo und einem künftigen Leitbild schlagen.
Ärztinnen in der Orthopädie und Unfallchirurgie in Deutschland: ein aktueller Status quo
Authors: Lutz Patricia M. , Lenz Julia , Achtnich Andrea , Geyer Stephanie
Published: December 2020

Hintergrund

Geschlechtsspezifische Unterschiede in der Arbeitswelt allgemein und im Bereich der Orthopädie und Unfallchirurgie im speziellen sind immer noch deutlich erkennbar, geraten aber immer stärker ins gesellschaftliche Bewusstsein.

Ziel

Analyse der geschlechtsspezifischen Entwicklung im Fachbereich Orthopädie und Unfallchirurgie in Deutschland über die vergangenen 15 Jahre und Erhebung des Status quo.

Methode

Erfassung der Entwicklung von Absolventinnen des Humanmedizinstudiums, des Frauenanteils in der vertragsärztlichen und klinischen Versorgung und des geschlechtsspezifischen Erwerbs einer orthopädischen/unfallchirurgischen Zusatzbezeichnung. Auswertung der geschlechtsspezifischen Mitglieder- oder Teilnehmerzahlen der entsprechenden Fachgesellschaften und der größten deutschen Kongresse für Orthopädie und Unfallchirurgie sowie der Habilitationszahlen im Bereich Orthopädie.

Ergebnisse und Diskussion

Der Anteil an Ärztinnen in verschiedenen Bereichen der Orthopädie und Unfallchirurgie in Klinik und Wissenschaft steigt. In Führungspositionen in Kliniken, beim Erwerb von Zusatzbezeichnungen und in den Vorständen von Fachgesellschaften besteht immer noch eine deutliche Diskrepanz. In manchen Bereichen, wie Kinder‑, Hand- oder Fuß‑/Sprunggelenkchirurgie ist der Frauenanteil höher als in anderen Teilbereichen der Orthopädie und Unfallchirurgie.
Moringa oleifera L. leaf powder as ingredient in gluten-free biscuits: nutritional and physicochemical characteristics
Authors: Giuberti Gianluca , Bresciani Andrea , Cervini Mariasole , Frustace Antonello , Marti Alessandra
Published: December 2020

Dried powder from Moringa oleifera L. leaves (MOLP) could be considered a promising naturally gluten-free (GF) ingredient to be added in the formulation of GF food products aiming to improve the overall nutritional characteristics. In this work, GF biscuits were formulated by replacing a commercial GF flour mix with 0, 5, 10, and 15 g/100 g of MOLP. Chemical composition, physical and textural characteristics, starch pasting properties, and the in vitro starch digestibility were considered. Adding MOLP increased the amount of protein and total dietary fibre. Even at the lowest MOLP-substitution level, the biscuits had a total dietary fibre content > 6 g/100 g dry matter. Differences in the chemical composition might account for differences in starch properties in terms of pasting behaviour and in vitro digestibility. Using MOLP decreased the in vitro starch hydrolysis index of biscuits, the lowest value (69.3) obtained at the greatest MOLP inclusion level. In addition, an increase in the resistant starch content was reported, passing from 1.1 to 2.7 g/100 g dry matter for GF biscuits containing 0 to 15 g/100 g of MOLP. Colour, spread ratio, and hardness were affected by MOLP inclusion. Biscuits containing 15 g/100 g of MOLP were characterized by the highest hardness value (41.9 N). Substitution level of 10 g/100 g should be considered the threshold level for obtaining a product with similar spread ratio than the control.
Trophic niches of benthic crustaceans in the Pechora Sea suggest that the invasive snow crab Chionoecetes opilio could be an important competitor
Authors: Gebruk Anna , Zalota Anna K. , Dgebuadze Polina , Ermilova Yulia , Spiridonov Vassily A. , Shabalin Nikolay , Henry Lea-Anne , Henley Sian F. , Mokievsky Vadim O.
Published: December 2020

Expanding human activities alongside climate change, the introduction of invasive species and water contamination pose multiple threats to the unique marine ecosystems of the Pechora Sea in the Russian Arctic. Baseline data on biodiversity and responses to environmental change are urgently needed. Benthic decapod crustaceans are globally distributed and play an important role in fisheries, yet their roles in food webs are less understood. In this study, we used an integrated approach combining stomach content analysis and stable isotope analyses (δ13C and δ15N) to examine the trophic niches of three decapod species in the Pechora Sea including the invasive snow crabChionoecetes opilioand two species of native decapods, the spider crabHyas araneusand the hermit crabPagurus pubescens. Stomach contents of 75 decapods were analysed (C. opilion = 23;H. araneusn = 9;P. pubescensn = 43), and 20 categories of prey items were identified with the most frequently occurring prey items being bivalve molluscs (Ciliatocardium ciliatum,Ennucula tenuis,Macoma calcarea),polychaetes, crustaceans and plant debris. Bayesian ellipse analyses of stable isotope signatures (n = 40) revealed thatC. opiliodisplays an overlapping trophic niche with the two native decapods, providing direct evidence that the invader likely competes for food resources with bothH. araneusandP. pubescens. As such, the presence of this invasive species could hold important consequences for trophic interactions, benthic ecosystem functioning and biodiversity. Microplastics were also found to be a likely stressor on this ecosystem, as 28% of all stomachs contained digested microplastics among other items. Long-term studies of benthic ecosystem structure and functioning are now needed to more fully understand the extent to which this new competitor may alter the future biodiversity of the Pechora Sea alongside the additional stressor of digested plastics.
Brain Tissue Conductivity Measurements with MR-Electrical Properties Tomography: An In Vivo Study
Authors: Mandija Stefano , Petrov Petar I. , Vink Jord J. T. , Neggers Sebastian F. W. , van den Berg Cornelis A. T.
Published: December 2020

First in vivo brain conductivity reconstructions using Helmholtz MR-Electrical Properties Tomography (MR-EPT) have been published. However, a large variation in the reconstructed conductivity values is reported and these values differ from ex vivo conductivity measurements. Given this lack of agreement, we performed an in vivo study on eight healthy subjects to provide reference in vivo brain conductivity values. MR-EPT reconstructions were performed at 3 T for eight healthy subjects. Mean conductivity and standard deviation values in the white matter, gray matter and cerebrospinal fluid (σWM, σGM, and σCSF) were computed for each subject before and after erosion of regions at tissue boundaries, which are affected by typical MR-EPT reconstruction errors. The obtained values were compared to the reported ex vivo literature values. To benchmark the accuracy of in vivo conductivity reconstructions, the same pipeline was applied to simulated data, which allow knowledge of ground truth conductivity. Provided sufficient boundary erosion, the in vivo σWM and σGM values obtained in this study agree for the first time with literature values measured ex vivo. This could not be verified for the CSF due to its limited spatial extension. Conductivity reconstructions from simulated data verified conductivity reconstructions from in vivo data and demonstrated the importance of discarding voxels at tissue boundaries. The presented σWM and σGM values can therefore be used for comparison in future studies employing different MR-EPT techniques.
QSAR and molecular docking for the search of AOX inhibitors: a rational drug discovery approach
Authors: Rosell-Hidalgo Alicia , Young Luke , Moore Anthony L. , Ghafourian Taravat
Published: December 2020

The alternative oxidase (AOX) is a monotopic diiron carboxylate protein that catalyses the oxidation of ubiquinol and the reduction of oxygen to water. Although a number of AOX inhibitors have been discovered, little is still known about the ligand–protein interaction and essential chemical characteristics of compounds required for a potent inhibition. Furthermore, owing to the rapidly growing resistance to existing inhibitors, new compounds with improved potency and pharmacokinetic properties are urgently required. In this study we used two computational approaches, ligand–protein docking and Quantitative Structure–Activity Relationships (QSAR) to investigate binding of AOX inhibitors to the enzyme and the molecular characteristics required for inhibition. Docking studies followed by protein–ligand interaction fingerprint (PLIF) analysis using the AOX enzyme and the mutated analogues revealed the importance of the residues Leu 122, Arg 118 and Thr 219 within the hydrophobic cavity. QSAR analysis, using stepwise regression analysis with experimentally obtained IC50 values as the response variable, resulted in a multiple regression model with a good prediction accuracy. The model highlighted the importance of the presence of hydrogen bonding acceptor groups on specific positions of the aromatic ring of ascofuranone derivatives, acidity of the compounds, and a large linker group on the compounds on the inhibitory effect of AOX.
Linking food systems and landscape sustainability in the Mediterranean region
Authors: García-Martín María , Torralba Mario , Quintas-Soriano Cristina , Kahl Johannes , Plieninger Tobias
Published: December 2020

Context

Global dynamics affect the sustainability of agricultural landscapes, but these cross-scale connections are understudied. Therefore, we combine food systems and landscape ecology, focusing on food products that provide a linkage between global consumers and landscapes of production (e.g., Douro Valley wine) which we call landscape products.

Objective

The aim of this study is to characterise Mediterranean landscape products based on experts’ perceptions by analysing their qualities, farming practices, and value chains, and to identify their ecological, cultural, and socio-economic outcomes in the landscapes of production.

Methods

Experts with specific knowledge on a landscape product were surveyed by email and their answers analysed using descriptive and ordination statistics. Fifty-four landscape products were characterised.

Results

Based on the experts’ perceptions, landscape products are high quality products, mainly using traditional knowledge and low intensity farming. They support biocultural diversity in the landscapes of production, but their positive socio-economic outcomes remain limited, with problems of inequity and lack of empowerment among producers and a tendency towards intensification or abandonment of the farming practices. We distinguished three types of products based on their localness and how their qualities were shared with consumers. Local products performed better in the ecological and cultural outcomes and products under certification in the economic. Labelling mechanisms and better organisation of producers could enhance these products and their positive outcomes.

Conclusions

Combining landscape ecology and food systems research allowed us better understand the outcomes of landscape products in the landscapes of production and suggest pathways for fostering landscape sustainability.
The Sun Through Time
Authors: Güdel Manuel
Published: December 2020

Magnetic activity of stars like the Sun evolves in time because of spin-down owing to angular momentum removal by a magnetized stellar wind. These magnetic fields are generated by an internal dynamo driven by convection and differential rotation. Spin-down therefore converges at an age of about 700 Myr for solar-mass stars to values uniquely determined by the stellar mass and age. Before that time, however, rotation periods and their evolution depend on the initial rotation period of a star after it has lost its protostellar/protoplanetary disk. This non-unique rotational evolution implies similar non-unique evolutions for stellar winds and for the stellar high-energy output. I present a summary of evolutionary trends for stellar rotation, stellar wind mass loss and stellar high-energy output based on observations and models.
Percolation and Reynolds Flow in Elastic Contacts of Isotropic and Anisotropic, Randomly Rough Surfaces
Authors: Wang Anle , Müser Martin H.
Published: December 2020

In this work, we numerically study the elastic contact between isotropic and anisotropic, rigid, randomly rough surfaces and linearly elastic counterfaces as well as the subsequent Reynolds flow through the gap between the two contacting solids. We find the percolation threshold to depend on the fluid flow direction when the Peklenik number indicates anisotropy unless the system size clearly exceeds the roll-off wave length parallel to the easy flow direction. A critical contact area near 0.415 is confirmed. Heuristically corrected effective-medium treatments satisfactorily provide Reynolds fluid flow conductances, e.g., for isotropic roughness, we identify accurate closed-form expressions, which only depend on the mean gap and the relative contact area.

Graphic Abstract
Cylinder-Flat Contact Mechanics with Surface Roughness
Authors: Tiwari A. , Persson B. N. J.
Published: December 2020

We study the nominal (ensemble averaged) contact pressure p(x) acting on a cylinder squeezed in contact with an elastic half space with random surface roughness. The contact pressure is Hertzian-like for $$\alpha < 0.01$$

α
<
0.01

and Gaussian-like for $$\alpha > 10$$

α
>
10

, where the dimensionless parameter $$\alpha = h_{\rm rms}/\delta $$

α
=

h
rms

/
δ

is the ratio between the root-mean-square roughness amplitude and the penetration for the smooth surfaces case (Hertz contact).
Experimental Investigation of Engineering Materials under Repetitive Impact with Slurry Conditions
Authors: Brownlie F. , Hodgkiess T. , Galloway A. M. , Pearson A.
Published: December 2020

In some industrial situations, components are subject to repetitive impact in the presence of a slurry. A novel repetitive impact-with-slurry test rig was developed to evaluate the behaviour of a wide range of engineering materials in such conditions. The test materials could be categorised into five main groups – heat treated steels, stainless steels, chromium cast irons, hardfacing coatings and superalloys. Three-dimensional surface topography was used to quantify the depths and volumes of the produced wear scars. Post-test metallurgical examination was also conducted to further evaluate the wear processes. The wear mechanisms could be split into two main groups of materials; ductile materials were observed to plastically deform and hard/brittle materials demonstrated cracking/spalling mechanisms. Hardened martensitic-type materials exhibited the greatest resistance to repetitive impact wear.
Schwachsinnig und abartig? Wahrgenommene Stigmatisierung und tatsächliche Etikettierungseffekte der alten und modernisierten Eingangsmerkmale in § 20 Strafgesetzbuch (StGB)
Authors: Rösch D. , Ruckelshaußen S. , Kirsch J. , Gerhards S. , Sroka L. A. , Imhoff R.
Published: December 2020

Bei der Beurteilung der Schuldfähigkeit eines Beschuldigten nach §§ 20, 21 StGB muss zunächst beurteilt werden, ob ein Eingangsmerkmal vorliegt, das verminderte oder reduzierte Schuldfähigkeit bedingen könnte, sowie ob dieses Eingangsmerkmal den Beschuldigten hinreichend in Einsichts- und/oder Steuerungsfähigkeit beeinflusst. Die bislang geltenden Eingangsmerkmale sind z. T. als veraltet und stigmatisierend kritisiert worden – insbesondere die der schweren anderen seelischen Abartigkeit und des Schwachsinns –, sodass im Jahr 2019 ein Gesetz zur Änderung des Strafgesetzbuches vorgelegt wurde, das eine Modernisierung der Begriffe beinhaltet. Die vorliegende Studie überprüft erstmals, ob die verschiedenen Begriffe (Intelligenzminderung vs. Schwachsinn; seelische Störung vs. seelische Abartigkeit) als unterschiedlich stigmatisierend wahrgenommen werden und zu unterschiedlicher Personenwahrnehmung führen. Zu diesem Zweck füllten 208 Personen, darunter rechtspsychologische Laien (n = 131) und Personen mit Vorwissen (n = 77), Onlinefragebogen aus, in denen sie sowohl anhand von Fallvignetten u. a. Schuldfähigkeit, Gefährlichkeit und Einsichtsfähigkeit von Personen einschätzen mussten als auch die unterschiedlichen Eingangsmerkmale direkt beurteilten. Die Ergebnisse zeigen, dass die überarbeiteten Begriffe als signifikant juristisch angemessener, positiver konnotiert, weniger stigmatisierend und weniger abwertend eingestuft werden. Auch bei einer qualitativen Untersuchung von Assoziationen der Probanden zu den jeweiligen Begriffen zeigten sich deutlich negativere Konnotationen der alten Begriffe. Gleichzeitig zeigte sich jedoch, dass sich die Bewertung von Individuen, die jeweils mit diesen Begriffen betitelt wurden, nicht unterschied, auch nicht bei rechtspsychologischen Laien. Sowohl rechtspsychologische Laien als auch Personen mit Vorwissen haben demnach zwar eindeutige Ansichten zu den vorliegenden Begriffen, diese wirken sich jedoch nicht signifikant auf ihre Personenwahrnehmung aus.
Ultimate Compressive Strength Computational Modeling for Stiffened Plate Panels with Nonuniform Thickness
Authors: Lee Hyun Ho , Paik Jeom Kee
Published: December 2020

The aim of this paper is to develop computational models for the ultimate compressive strength analysis of stiffened plate panels with nonuniform thickness. Modeling welding-induced initial deformations and residual stresses was presented with the measured data. Three methods, i.e., ANSYS finite element method, ALPS/SPINE incremental Galerkin method, and ALPS/ULSAP analytical method, were employed together with existing test database obtained from a full-scale collapse testing of steel-stiffened plate structures. Sensitivity study was conducted with varying the difference in plate thickness to define a representative (equivalent) thickness for plate panels with nonuniform thickness. Guidelines are provided for structural modeling to compute the ultimate compressive strength of plate panels with variable thickness.
Cardiometabolic Morbidity and Mortality with Smoking Cessation, Review of Recommendations for People with Diabetes and Obesity
Authors: Kos Katarina
Published: December 2020

Purpose of Review

Obesity is closely linked with the pathogenesis of type 2 diabetes (T2DM) and cardiovascular disease (CVD), and whilst smoking cessation is associated with weight gain, there are concerns that this weight gain may offset the benefit of CVD risk reduction especially in those with considerable post-cessation weight gain. The aim of this narrative review is to evaluate recent evidence on smoking cessation and cardiometabolic outcomes and discuss limitations of current knowledge and studies.

Recent Findings

Nicotine is a key player in modulating energy balance by influencing lipid storage in adipose tissue by affecting lipolysis, energy input by modulating appetite and energy output by increasing sympathetic drive and thermogenesis. It also increases insulin resistance and promotes abdominal obesity. The CVD risk and mortality associated with cigarette smoking potentiate the CVD risks in patients with diabetes. Evidence supports the benefit of quitting cigarette smoking regardless of any subsequent weight gain. Data suggests that the cardiometabolic risk is limited to the first few years and that cardiovascular health and mortality benefit of smoking cessation outweighs the harm related to weight gain. This weight gain can be limited by nicotine replacement of which e-cigarettes (vaping) are increasingly popular if it is not an alternative to cigarette smoking. However, long-term health data on e-cigarettes is needed prior to formal recommendation for its use in smoking cessation.

The recommendation for cessation of cigarette smoking is justified for those at high risk of weight gain and diabetes. However, for most benefit, consideration should be given for personalized weight management to limit weight gain. Awareness of a ‘lean paradox’ by which lower weight is associated with increased CVD risk may help to improve motivation and insight into the bias of smoking, health and body composition otherwise known to epidemiologists as the ‘obesity paradox’.
Addressing Parsons in Sociological Textbooks: Past Conflicts, Contemporary Readers, and their Future Gains
Authors: Mahlert Bettina
Published: December 2020

The paper provides insights on the contemporary relevance of Talcott Parsons’s writings by analyzing 20 textbooks from Austria, Germany, Great Britain and the United States, published in 1999–2019. Whether having knowledge of Parsons is helpful to today’s students and other interested readers, and what knowledge, deserves consideration. Therefore , the paper asks: Whichfuturegains of readers did textbook authors envision when they chose, in their ownpresent, to discuss (or not) sociological writings fromlong ago? In order to understand what future opportunities authors wanted to create for readers, as well as how they chose to discuss Parsons to this end, the paper draws on Niklas Luhmann’s notion of memory. The analysis reveals several key competencies that student and other interested readers might acquire through having knowledge of Parsons’ writings and its critiques. These potentials would have gone unnoticed if authors had assessed Parsons’s relevance only according to whether he adequately considered conflict or not, as has been done in many debates about his work until today. Moreover, through analyzing how authors remembered Parsons, I distilled two key selective criteria: First, whatmust be rememberedin order to enable readers to acquire those competencies? Second, which memories would be impeding for readers and thusbe better left out? These criteria are relevant for research, as well. Looking at the future, it would be desirable that sociologists let Parsons assist them in their research in many different ways, if possible. As a result, we might see a revival of Parsons that enables genuine advancement.
Clifford systems, Clifford structures, and their canonical differential forms
Authors: Boydon Kai Brynne M. , Piccinni Paolo
Published: December 2020

A comparison among different constructions in$$\mathbb {H}^2 \cong {\mathbb {R}}^8$$H2≅R8of the quaternionic 4-form$$\Phi _{\text {Sp}(2)\text {Sp}(1)}$$ΦSp(2)Sp(1)and of the Cayley calibration$$\Phi _{\text {Spin}(7)}$$ΦSpin(7)shows that one can start for them from the same collections of “Kähler 2-forms”, entering both in quaternion Kähler and in$$\text {Spin}(7)$$Spin(7)geometry. This comparison relates with the notions of even Clifford structure and of Clifford system. Going to dimension 16, similar constructions allow to write explicit formulas in$$\mathbb {R}^{16}$$R16for the canonical 4-forms$$\Phi _{\text {Spin}(8)}$$ΦSpin(8)and$$\Phi _{\text {Spin}(7)\text {U}(1)}$$ΦSpin(7)U(1), associated with Clifford systems related with the subgroups$$\text {Spin}(8)$$Spin(8)and$$\text {Spin}(7)\text {U}(1)$$Spin(7)U(1)of$$\text {SO}(16)$$SO(16). We characterize the calibrated 4-planes of the 4-forms$$\Phi _{\text {Spin}(8)}$$ΦSpin(8)and$$\Phi _{\text {Spin}(7)\text {U}(1)}$$ΦSpin(7)U(1), extending in two different ways the notion of Cayley 4-plane to dimension 16.
Transgender Women in the Female Category of Sport: Perspectives on Testosterone Suppression and Performance Advantage
Authors: Hilton Emma N. , Lundberg Tommy R.
Published: December 2020

Males enjoy physical performance advantages over females within competitive sport. The sex-based segregation into male and female sporting categories does not account for transgender persons who experience incongruence between their biological sex and their experienced gender identity. Accordingly, the International Olympic Committee (IOC) determined criteria by which a transgender woman may be eligible to compete in the female category, requiring total serum testosterone levels to be suppressed below 10 nmol/L for at least 12 months prior to and during competition. Whether this regulation removes the male performance advantage has not been scrutinized. Here, we review how differences in biological characteristics between biological males and females affect sporting performance and assess whether evidence exists to support the assumption that testosterone suppression in transgender women removes the male performance advantage and thus delivers fair and safe competition. We report that the performance gap between males and females becomes significant at puberty and often amounts to 10–50% depending on sport. The performance gap is more pronounced in sporting activities relying on muscle mass and explosive strength, particularly in the upper body. Longitudinal studies examining the effects of testosterone suppression on muscle mass and strength in transgender women consistently show very modest changes, where the loss of lean body mass, muscle area and strength typically amounts to approximately 5% after 12 months of treatment. Thus, the muscular advantage enjoyed by transgender women is only minimally reduced when testosterone is suppressed. Sports organizations should consider this evidence when reassessing current policies regarding participation of transgender women in the female category of sport.