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Quadruple[6]Helicene Featuring Pyrene Core:Unraveling Contorted Aromatic Core with Larger Effective Conjugation

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Precision Chemistry 2024年第9期2卷 488-494页

作者： Christopher Wallerius Otgonbayar Erdene-Ochir Eva Van Doeselar Ronald Alle Anh Tu Nguyen Marvin F.Schumacher Arne Lützen klaus Meerholz Sai Ho Pun Department of Chemistry University of CologneCologne 50939Germany Kekulé-Institute of Organic Chemistry and Biochemistry University of BonnBonn 53121Germany Department of Chemistry Hong Kong University of Science and TechnologyClean Water BayHong KongChina

Multiple helicenes display distinct aromatic cores characterized by highly twisted rings that are shared or fused with constituent helicene *** these aromatic cores unlocks avenues for creating multiple helicenes with distinct properties and *** we report the synthesis of a quadruple[6]helicene featuring pyrene as the aromatic *** synthesis involved key steps of the annulativeπ-extension reaction and Scholl *** extending multiple helicenes along the axial direction,the degree of contortion of the aromatic core can be controlled from nearly flat to highly ***,quadruple[6]-helicene exhibits a significant red-shift of 0.49 eV compared to quadruple[4]-helicenes,of which the red-shift arises from bothπ-extension and augmented effective conjugation due to enhanced *** chemical calculations demonstrate that the degree of contortion in the pyrene core adeptly governs the energy levels of the HOMO and LUMO,which offers an alternative strategy beyond mere enlargement of theπ*** intriguing serendipitous finding reveals the formation of one-molecule-thick supramolecular homochiral nanosheets through selfinterlocking interactions of enantiomers in single crystals,a rare packing motif for multiple helicenes.

关键词： Helicenes Polycyclic aromatics Pyrene Core contortion Effective conjugation

Testing and modelling of transient adhesion phenomena in rolling-sliding contacts

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Friction 2024年第5期12卷 1016-1027页

作者： Daniel KVARDA Alexander MEIERHOFER klaus SIX Faculty of Mechanical Engineering Brno University of TechnologyBrno61669Czech Republic Virtual Vehicle Research gmbH Graz8010Austria

Transient adhesion effects in rolling–sliding contacts influence all aspects of train–track *** is of high importance specifically when these effects result in critically low adhesion,which poses a risk to traction and braking of railway *** study presents a model that can replicate the transient changes of the coefficient of adhesion with tested water and solid particle *** experimental data for the model are measured using a commercial ball-on-disc *** experimental results showed a liquid reservoir in front of the contact area that slowly reduces in *** observation was used in the modelling approach to divide the calculation into two stages where the reservoir is present and when it *** model was able to reproduce the occurrence of low adhesion region seen in experimental results with different particle concentrations.

关键词： coefficient of adhesion tribology transient effects wheel-rail contact

Book review “Wattles: Australian Acacia species around the world” by David M. Richardson, Johannes J. Le Roux and Elizabete Marchante

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Forest Ecosystems 2024年第2期11卷 140-141页

作者： klaus von gadow Faculty of Forestry and Forest Ecology Georg-August-University GöttingenBüsgenweg 5D-37077GöttingenGermany Department of Forestry and Wood Science Faculty of AgriSciencesStellenbosch UniversityStellenbosch Private Bag X1Stellenbosch7602South Africa

In a world of google and AI, developing an encyclopedic coverage of a theme that is of great interest to biologists, social scientists, politicians and environmental managers, is a daunting challenge. Wattles is a book that presents new knowledge, makes interesting reading, and has the potential to stimulate research in a variety of disciplines. We learn that Acacia, commonly known as the wattles or acacias, is a genus of shrubs and trees comprising 1,083 species of which 417 are known to have been introduced to areas outside their native range. We are surprised to read that Australian acacias are found almost everywhere, in virtually all terrestrial habitats, including woodlands, grasslands, alpine settings,rainforests, coastal dunes and deserts, causing major environmental and socio-economic changes in the invaded regions. Until recently, Acacia comprised a group of plant species native to Africa, South America and Australasia, but the name is now reserved for species predominantly from Australia, including some from Southeast Asia. The genus name Acacia is Neo-Latin, and refers to a preparation extracted from the leaves and fruit pods of Vachellia nilotica, the original type of the genus.

关键词： Richardson outside Latin

Learning about good nutrition with the 5-color front-of-package label"Nutri-Score":an experimental study

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Food Science and Human Wellness 2024年第3期13卷 1195-1200页

作者： Robin C.Hau klaus W.Lange University of Applied Sciences Landshut Landshut 84036Germany Faculty of Human Sciences University of RegensburgRegensburg 93040Germany

The Nutri-Score is a 5-color front-of-pack nutrition label designed to provide consumers with an easily understandable guideline to the healthiness of food *** impact that the Nutri-Score may have on consumers'choices is unclear since different experimental paradigms have found vastly different effect *** the present study,we have investigated how student participants change a hypothetical personal 1-daydietary plan after a learning phase during which they learn about the Nutri-Scores of the available food *** were instructed to compose a healthy diet plan in order that the question of whether the NutriScore would improve their ability to compose a healthy dietary plan could be investigated,independent of the question of whether they would apply this knowledge in their ordinary *** found a substantial(Cohen's d=0.86)positive impact on nutritional quality(as measured by the Nutrient Profiling System score of the Food Standards Agency)and a medium-sized(Cohen's d=0.43)reduction of energy *** content reduction was larger for participants who had initially composed plans with higher energy *** results suggest that the Nutri-Score has the potential to guide consumers to healthier food *** remains unclear,however,whether this potential will be reflected in real-life dietary choices.

关键词： Nutri-Score Front-of-package label Nudge Nutrition Health

Dieback of managed spruce stands in western germany promotes beetle diversity

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Journal of Forestry Research 2024年第3期35卷 55-71页

作者： Eva Plath Chantal Trauth Jan gerhards Laura griebel klaus Fischer Department Biology Institute of Integrated Natural SciencesKoblenz-Landau University56070 KoblenzGermany

Biodiversity loss is a significant problem at a global scale and may be amplified by climate *** recent years,coniferous forests have had substantial die-back across Europe due to drought and subsequent bark-beetle *** many studies on the consequences of disturbance and subsequent management have focused on natural stands,management implications for managed spruce stands are not well understood,even though such stands are widespread throughout *** this study,beetle taxonomy,conservation value,and community com-position are compared among spruce plantations and four post-disturbance management approaches:standing dead-wood,lying deadwood,clear cuts,and long-term *** and community composition differed significantly among management categories,while different beetle fami-lies responded *** spruce stands harbored the lowest beetle diversity while the highest taxonomic diver-sity and conservation value was on clear cuts and stands with lying or standing *** proportion of forest specialists was highest in successional *** summary,different forest management categories harbored distinct beetle communities at the family-,species-,and ecological guild ***,post-disturbance management should consider the landscape scale and include different management *** enhances landscape heterogeneity and thus overall biodiversity but could also mitigate negative impacts of natural disturbances on ecosystem services.

关键词： Bark-beetle outbreak Forest dieback Spruce Deadwood Nature conservation Beetle biodiversity-Coleoptera Coniferous forests

An explainable AI framework for robust and transparent data-driven wind turbine power curve models

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Energy and AI 2024年第1期15卷 312-327页

作者： Simon Letzgus klaus-Robert Müller Machine Learning group Technische Universitβe BerlinStraβe des 17.Juni 135Berlin10623Germany Berlin Institute for the Foundations of Learning and Data Berlin10587Germany Department of Artificial Intelligence Korea UniversitySeoul136-713South Korea Max Planck Institute for Informatics Saarbrücken66123Germany

In recent years,increasingly complex machine learning methods have become state-of-the-art in modelling wind turbine power curves based on operational *** these methods often exhibit superior performance on test sets,they face criticism due to a perceived lack of transparency and concerns about their robustness in dynamic,non-stationary environments encountered by wind *** this work,we address these issues and present a framework that leverages explainable artificial intelligence methods to gain systematic insights into data-driven power curve *** its core,we propose a metric to quantify how well a learned model strategy aligns with the underlying physical principles of the *** novel tool enables model validation beyond the conventional error metrics in an automated *** demonstrate,for instance,its capacity as an indicator for model generalization even when limited data is ***,it facilitates understanding how decisions made during the machine learning development process,such as data selection,pre-processing,or training parameters,affect learned *** a result,we obtain physically more reasonable models,a prerequisite not only for robustness but also for meaningful insights into turbine operation by domain *** latter,we illustrate in the context of wind turbine performance *** summary,the framework aims to guide researchers and practitioners alike toward a more informed selection and utilization of data-driven wind turbine power curve models.

关键词： Explainable AI(XAI) Machine learning Wind energy Wind turbine power curve SCADA Condition monitoring

Boosting liver regeneration: kinase inhibitor as a new tool to prevent liver failure

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Signal Transduction and Targeted Therapy 2024年第8期9卷 3145-3146页

作者： Anna Sichler Norbert Huser klaus-Peter Janssen Department of Surgery School of Medicine and HealthTechnical University of MunichMunichGermany

In a recent manuscript in Cell,a first-in-class small molecule inhibitor of the kinase MKK4(mitogen-activated protein kinase kinase 4)was described that greatly enhances liver regeneration after partial hepatectomy in animal models,with an excellent safety profile in humans.1 The findings of Zwirner et *** promise to alter the clinical management of liver failure in critically ill patients.

关键词： liver al. clinical

Food intolerance and the few-foods(or oligoantigenic)diet in children with attention-deficit hyperactivity disorder

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Food Science and Human Wellness 2024年第4期13卷 1729-1738页

作者： klaus W.Lange Andreas Reissmann Yukiko Nakamura Katharina M.Lange Faculty of Human Sciences University of RegensburgRegensburg 93040Germany Department of Psychology University of BathBath BA27AYUnited Kingdom

The hypothesis that some children with attention-deficit hyperactivity disorder(ADHD)may show sensitivity or allergic reactions to various food items has led to the development of the the few-foods(or oligoantigenic)*** rationale of the diet is to eliminate certain foods from the diet in order to exclude potential allergens contained either naturally in food or in artificial ingredients with allergenic *** oligoantigenic diet attempts to identify individual foods to which a person might be ***,ADHD symptoms are monitored while multiple foods are excluded from the ***,if symptoms remit,foods are re-introduced,while observing the individual for the return of *** advantage of the oligoantigenic diet is that it can be tailored to the individual.A growing body of evidence suggests that behavioral symptoms of subgroups of children with ADHD may benefit from the elimination of certain *** effect sizes of an oligoantigenic diet regarding improvement of ADHD symptoms have been found to be medium to *** evidence suggests that the investigation of the role of food hypersensitivities in ADHD is a promising avenue worthy of further *** large-scale,randomized controlled studies including assessment of long-term outcome are therefore warranted.

关键词： Attention-deficit hyperactivity disorder Food intolerance Few-foods diet Etiology Treatment

grouping tree species to estimate basal area increment in temperate multispecies forests in Durango,Mexico

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Forest Ecosystems 2024年第1期11卷 1-13页

作者： Jaime Roberto Padilla-Martínez Carola Paul Kai Husmann Jose Javier Corral-Rivas klaus von gadow Department of Forest Economics and Sustainable Land-use Planning Faculty of Forest Sciences and Forest EcologyUniversity of GottingenBüsgenweg 137077GottingenGermany Facultad de Ciencias Forestales Universidad Juarez del Estado de DurangoRío Papaloapan y Boulevard Durango S/N34120DurangoMexico Faculty of Forestry and Forest Ecology Georg-August-UniversitatBüsgenweg 537077GottingenGermany Department of Forestry and Wood Science Faculty of AgriSciencesStellenbosch UniversityStellenbosch Private Bag X1Stellenbosch7602South Africa

Multispecies forests have received increased scientific attention,driven by the hypothesis that biodiversity improves ecological ***,a greater species diversity presents challenges for forest management and *** study aims to develop basal area growth models for tree species *** analysis is based on a dataset of 423 permanent plots(2,500 m^(2))located in temperate forests in Durango,***,we define tree species cohorts based on individual and neighborhood-based variables using a combination of principal component and cluster ***,we estimate the basal area increment of each cohort through the generalized additive model to describe the effect of tree size,competition,stand density and site *** principal component and cluster analyses assign a total of 37 tree species to eight cohorts that differed primarily with regard to the distribution of tree size and vertical position within the *** generalized additive models provide satisfactory estimates of tree growth for the species cohorts,explaining between 19 and 53 percent of the total variation of basal area increment,and highlight the following results:i)most cohorts show a"rise-and-fall"effect of tree size on tree growth;ii)surprisingly,the competition index"basal area of larger trees"had showed a positive effect in four of the eight cohorts;iii)stand density had a negative effect on basal area increment,though the effect was minor in medium-and high-density stands,and iv)basal area growth was positively correlated with site quality except for an oak *** developed species cohorts and growth models provide insight into their particular ecological features and growth patterns that may support the development of sustainable management strategies for temperate multispecies forests.

关键词： Temperate multispecies forests Cluster analysis Basal area increment generalized additive models