检索结果-南通市图书馆

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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 interaction.This is of high importance specifically when these effects result in critically low adhesion,which poses a risk to traction and braking of railway vehicles.This study presents a model that can replicate the transient changes of the coefficient of adhesion with tested water and solid particle mix.The experimental data for the model are measured using a commercial ball-on-disc tribometer.The experimental results showed a liquid reservoir in front of the contact area that slowly reduces in size.This observation was used in the modelling approach to divide the calculation into two stages where the reservoir is present and when it disappears.The 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

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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 products.The impact that the Nutri-Score may have on consumers'choices is unclear since different experimental paradigms have found vastly different effect sizes.In 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 items.Participants 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 lives.We 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.Energy content reduction was larger for participants who had initially composed plans with higher energy content.The results suggest that the Nutri-Score has the potential to guide consumers to healthier food choices.It 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

在线全文

学校读者我要写书评

暂无评论

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 change.In recent years,coniferous forests have had substantial die-back across Europe due to drought and subsequent bark-beetle outbreaks.As 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 Europe.In 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 succession.Diversity and community composition differed significantly among management categories,while different beetle fami-lies responded similarly.Intact 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 deadwood.The proportion of forest specialists was highest in successional forests.In summary,different forest management categories harbored distinct beetle communities at the family-,species-,and ecological guild levels.Therefore,post-disturbance management should consider the landscape scale and include different management types.This 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

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

在线全文

学校读者我要写书评

暂无评论

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

Adverse events of sacral neuromodulation for fecal incontinence reported to the federal drug administration

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Pharmacology and Therapeutics 2016年第2期7卷 294-305页

作者： klaus bielefeldt Division of Gastroenterology University of Pittsburgh Medical Center

AIM:To investigate the nature and severity of AE related to sacral neurostimulation(SNS).METHODS:Based on Pubmed and Embase searches,we identified published trials and case series of SNS for fecal incontinence(FI)and extracted data on adverse events,requiring an active intervention.Those problems were operationally defined as infection,device removal explant or need for lead and/or generator replacement.In addition,we analyzed the Manufacturer and User Device Experience registry of the Federal Drug Administration for the months of August-October of2015.Events were included if the report specifically mentioned gastrointestinal(GI),bowel and FI as indication and if the narrative did not focus on bladder symptoms.The classification,reporter,the date of the recorded complaint,time between initial implant and report,the type of AE,steps taken and outcome were extracted from the report.In cases of device removal or replacement,we looked for confirmatory comments by healthcare providers or the manufacturer.RESULTS:Published studies reported adverse events and reoperation rates for 1954 patients,followed for 27(1-117)mo.Reoperation rates were 18.6%(14.2-23.9)with device explants accounting for 10.0%(7.8-12.7)of secondary surgeries;rates of device replacement or explant or pocket site and electrode revisions increased with longer follow up.During the period examined,the FDA received 1684 reports of AE related to SNS with FI or GI listed as indication.A total of 652 reports met the inclusion criteria,with 52.7%specifically listing FI.Lack or loss of benefit(48.9%),pain or dysesthesia(27.8%)and complication at the generator implantation site(8.7%)were most commonly listed.Complaints led to secondary surgeries in 29.7%of the AE.Reoperations were performed to explant(38.2%)or replace(46.5%)the device or a lead,or revise the generator pocket(14.6%).Conservative management changes mostly involved changes in stimulation parameters(44.5%),which successfully addressed concerns in 35.2%of cases that included information about treat

关键词： Sacral nerve stimulation Implanted medical devices Treatment complications Defecation disorders Device registry

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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)diet.The 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 properties.The oligoantigenic diet attempts to identify individual foods to which a person might be sensitive.First,ADHD symptoms are monitored while multiple foods are excluded from the diet.Subsequently,if symptoms remit,foods are re-introduced,while observing the individual for the return of symptoms.An 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 foods.The effect sizes of an oligoantigenic diet regarding improvement of ADHD symptoms have been found to be medium to large.Available evidence suggests that the investigation of the role of food hypersensitivities in ADHD is a promising avenue worthy of further exploration.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

在线全文

学校读者我要写书评

暂无评论

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 resilience.However,a greater species diversity presents challenges for forest management and research.Our study aims to develop basal area growth models for tree species cohorts.The analysis is based on a dataset of 423 permanent plots(2,500 m^(2))located in temperate forests in Durango,Mexico.First,we define tree species cohorts based on individual and neighborhood-based variables using a combination of principal component and cluster analyses.Then,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 quality.The 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 community.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 cohort.The 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

Theoretical study of superradiant masing with solid-state spins at room temperature

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 38-47页

作者： Qilong Wu Yuan Zhang Hao Wu Shi-Lei Su Kai-Kai Liu Mark Oxborrow Chong-Xin Shan klaus Mølmer Henan Key Laboratory of Diamond Optoelectronic Materials and Devices Key Laboratory of Material Physics Ministry of EducationSchool of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China Institute of Quantum Materials and Physics Henan Academy of SciencesZhengzhou 450046China Center for Quantum Technology Research and Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurements School of PhysicsBeijing Institute of TechnologyBeijing 100081China Beijing Academy of Quantum Information Sciences Beijing 100193China Department of Materials Imperial College LondonLondon SW72AZUK Niels Bohr Institute University of CopenhagenCopenhagen 2100Denmark

Steady-state superradiance and superradiant lasing attract significant attentions in the field of optical lattice clocks,but have not been achieved yet due to the technical challenges and atom loss problem.In this article,we propose that their counter-part may be observed in the microwave domain with solid-state spins,i.e.,nitrogen-vacancy center spins and pentacene molecular spins,coupled to microwave resonator at room temperature with realistic technical restrictions.To validate our proposal,we investigate systematically the system dynamics and steady-state by solving quantum master equations for the multi-level and multi-process dynamics of trillions of spins.Our calculations show that the superradiant Rabi oscillations occur firstly due to transitions among different Dicke states,and the subsequent continuous-wave superradiant masing can achieve a linewidth well below millihertz.Our work may guide further exploration of transient and steady-state superradiant masing with the mentioned and other solid-state spins systems.The ultra-narrow linewidth may find applications in deep-space communications,radio astronomy and high-precision metrology.

关键词： solid-state spins superradiance maser

Rescue of p53 functions by in vitro-transcribed mRNA impedes the growth of high-grade serous ovarian cancer

在线全文

学校读者我要写书评

暂无评论

Cancer Communications 2024年第1期44卷 101-126页

作者： Monika Raab Izabela Kostova Samuel Peña-Llopis Daniela Fietz Monika Kressin Seyed Mohsen Aberoumandi Evelyn Ullrich Sven Becker Mourad Sanhaji klaus Strebhardt Department of Gynecology Medical SchoolGoethe-UniversityFrankfurt am MainGermany Translational Genomics in Solid Tumors West German Cancer CenterUniversity HospitalEssenGermany German Cancer Consortium(DKTK) EssenGermany German Cancer Research Center(DKFZ) HeidelbergGermany Histology and Embryology Institute for Veterinary AnatomyGiessenGermany Franfurt Cancer Institute(FCI) Goethe UniversityFrankfurt am MainGermany German Cancer Consortium(DKTK) Partner site Frankfurt/Mainza partnership between DKFZ and University Hospital FrankfurtFrankfurt am MainGermany Experimental Immunology Department for Children and Adolescents MedicineUniversity Hospital FrankfurtGoethe UniversityFrankfurt am MainGermany

Background:The cellular tumor protein p53(TP53)is a tumor suppressor gene that is frequently mutated in human cancers.Among various cancer types,the very aggressive high-grade serous ovarian carcinoma(HGSOC)exhibits the high-est prevalence of TP53 mutations,present in>96%of cases.Despite intensive efforts to reactivate p53,no clinical drug has been approved to rescue p53 func-tion.In this study,our primary objective was to administer in vitro-transcribed(IVT)wild-type(WT)p53-mRNA to HGSOC cell lines,primary cells,and ortho-topic mouse models,with the aim of exploring its impact on inhibiting tumor growth and dissemination,both in vitro and in vivo.Methods:To restore the activity of p53,WT p53 was exogenously expressed in HGSOC cell lines using a mammalian vector system.Moreover,IVT WT p53 mRNA was delivered into different HGSOC model systems(primary cells and patient-derived organoids)using liposomes and studied for proliferation,cell cycle progression,apoptosis,colony formation,and chromosomal instabil-ity.Transcriptomic alterations induced by p53 mRNA were analyzed using RNA sequencing in OVCAR-8 and primary HGSOC cells,followed by ingenuity path-way analysis.In vivo effects on tumor growth and metastasis were studied using orthotopic xenografts and metastatic intraperitoneal mouse models.Results:Reactivation of the TP53 tumor suppressor gene was explored in differ-ent HGSOC model systems using newly designed IVT mRNA-based methods.The introduction of WT p53 mRNA triggered dose-dependent apoptosis,cell cycle arrest,and potent long-lasting inhibition of HGSOC cell proliferation.Transcriptome analysis of OVCAR-8 cells upon mRNA-based p53 reactivation revealed significant alterations in gene expression related to p53 signaling,such as apoptosis,cell cycle regulation,and DNA damage.Restoring p53 function concurrently reduces chromosomal instability within the HGSOC cells,under-scoring its crucial contribution in safeguarding genomic integrity by moderating the baseline occurrence of double-strand breaks arising fro

关键词： apoptosis cell cycle chromosomal instability HGSOC metastatic intraperitoneal mouse model HGSOC orthotopic Xenograft model high-grade serous ovarian cancer in vitro-transcribed p53-mRNA liposomal IVT mRNA delivery system patient-derived organoid patient-derived primary cancer cell