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Discovery of gargantulides B and C,new 52-membered macrolactones from Amycolatopsis *** absolute stereochemistry of the gargantulide family

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Organic Chemistry Frontiers 2022年第2期9卷 462-470页

作者： Daniel Carretero-Molina Francisco Javier Ortiz-López tetiana gren Daniel Oves-Costales Jesús Martín Fernando Román-Hurtado Tue Sparholt Jorgensen Mercedes de la Cruz Caridad Díaz Francisca Vicente Kai Blin Fernando Reyes Tilmann Weber Olga Genilloud Fundación MEDINA Centro de Excelencia en Investigación de Medicamentos Innovadores en AndalucíaAvda.del Conocimiento 3418016 ArmillaGranadaSpain The Novo Nordisk Foundation Center for Biosustainability Technical University of DenmarkKemitorvetbuilding 2202800 Kgs.LyngbyDenmark

Gargantulides B and C,two new and highly complex 52-membered glycosylated macrolactones,were isolated from Amycolatopsis *** CA-230715 during an antibacterial screening *** structures of these giant macrolides were elucidated by 2D NMR spectroscopy and shown to be related to gargantulide A,although containing additional β-glucopyranose and/orα-arabinofuranose monosaccharides separately attached to their *** sequencing allowed the identification of a strikingly large 216 kbp biosynthetic gene cluster,among the largest type Ⅰ PKS clusters described so far,and the proposal of a previously unreported biosynthetic pathway for gargantulides *** absolute configurations of gargantulides B and C were assigned based on a combination of NMR and bioinformatics analysis of ketoreductase and enoylreductase domains within the multimodular type Ⅰ *** addition,the absolute stereochemistry of gargantulide A has now been revised and *** B and C display potent antibacterial activity against a set of drug-resistant Gram-positive bacteria and moderate activity against the clinically relevant Gram-negative pathogen Acinetobacter baumannii.

关键词： absolute membered backbone

Determination of riding comfort on cycleways using a smartphone application

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第4期11卷 747-760页

作者： Anna Niska Leif Sj?gren Peter Andrén Christian Weber Tineke de Jong Aslak Fyhri Department of Infrastructure Maintenance Swedish National Road and Transport Research Institute (VTI) Department of Safety and Behavior Institute of Transport Economics

Well maintained cycleways will encourage more people to cycle, as the condition of cycleways is important for the safety, accessibility and riding comfort of cyclists. Despite that, only a few models used to describe the quality of service for cyclists take the surface condition into account. Objective measuring methods are needed to enable reliable and effective assessment of surface conditions, and measurable performance criteria related to the needs of cyclists should be developed. The purpose of this study has been to test the reliability and validity of using accelerometers in smartphones to assess the riding comfort on cycleways. A smartphone application converting three-dimensional accelerometer measurements into a single indicator for cycleways has been used to assess road surfaces in two field studies, in Sweden and Norway, respectively. Both studies assessed test sections of varying quality. To relate the measurements to subjective riding comfort assessments by cyclists, recruited cyclists collected quantitative data using the app, whilst also rating their perceived riding comfort by completing a survey. Measurements were also related to standard road surface condition indicators, generated from a road surface tester equipped with 19 laser sensors: international roughness index(IRI), mega-and macrotexture. The results show that it is possible to describe the unevenness of a cycleway using the technology present in smartphones. A software application can be used to collect and analyse data from the acceleration sensors in the phone, which can then be used to describe the riding comfort of cyclists. It is mainly the unevenness in the 50-1000 mm sizerange that create the greatest discomfort for cyclists, and intermittent vibrations are perceived as more uncomfortable than more evenly distributed vibrations. Therefore, IRI is not a relevant measurement for describing the riding comfort of cyclists.

关键词： Cyclist Comfort Assessment Road surface measurement Smartphone application

Electrostatic interaction-mediated 1:1 complexes for high-contrast mitochondrial-targeted phosphorescence bioimaging

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Science China Chemistry 2024年第10期67卷 3406-3413页

作者： Jianshuo Cheng Hao Sun Lulu Zhou Glib V.Baryshnikov Mouwei Liu Shen Shen Hans ?gren Liangliang Zhu State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan University Laboratory of Organic Electronics Department of Science and TechnologyLink?ping University Department of Physics and Astronomy Uppsala University

Organelle-targeted imaging can provide information on cellular functions and intracellular interactions, being significant for disease diagnosis. The use of room-temperature phosphorescence(RTP) in organelle-targeted imaging can fully utilize its unique characteristics of long wavelength and deep penetration. However, this technology has long been plagued by insufficient probe targeting and limited luminous intensity. In this work, we prepared a series of complexes composed of multicationic persulfurated arenes and biomacromolecules via electrostatic interactions in 1:1 stoichiometry for high-contrast mitochondrial-targeted RTP imaging. Such an electrostatic interaction design effectively prevented the self-aggregation of the probes, which is not conducive to mitochondrial targeting. Simultaneously, it suppressed the non-radiative decay to the maximum extent, enabling the probes to exhibit strong RTP signals both in aqueous solution and at the cellular level. Furthermore, the biomacromolecules can serve as carriers for an electrostatic interaction transfer of the persulfurated arenes to mitochondria. This leads to high mitochondrial targeting Pearson's correlation coefficients of the probes and high-contrast RTP imaging effects, as well as the independence of the co-incubated probe concentration. These results provide new insights for the development of targeted imaging technologies.

关键词： room-temperature phosphorescence mitochondrial targeting bioimaging complex electrostatic interaction

Functional characterization,structural basis,and protein engineering of a rare flavonoid 2′-O-glycosyltransferase from Scutellaria baicalensis

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Acta Pharmaceutica Sinica B 2024年第8期14卷 3746-3759页

作者： Zilong Wang Xueqing Du Guo Ye Haotian Wang Yizhan Liu Chenrui Liu Fudong Li HansÅgren Yang Zhou Junhao Li Chao He De-An Guo Min Ye State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China Anhui Key Laboratory of Modern Biomanufacturing and School of Life Sciences Anhui UniversityHefei 230601China National Science Center for Physical Sciences at Microscale Division of Molecular&Cell Biophysics and School of Life Sciences University of Science and Technology of ChinaHefei 230026China Department of Physics and Astronomy Uppsala UniversityUppsala SE-75120Sweden School of Pharmacy Jinan UniversityGuangzhou 510632China Shanghai Research Center for Modernization of Traditional Chinese Medicine Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China

Glycosylation is an important post-modification reaction in plant secondary metabolism,and contributes to structural diversity of bioactive natural *** plants,glycosylation is usually catalyzed by *** 2′-O-glycosides are rare ***,no UGTs have been reported,thus far,to specifically catalyze 2′-O-glycosylation of *** this work,UGT71AP2 was identified from the medicinal plant Scutellaria baicalensis as the first flavonoid 2′-*** could preferentially transfer a glycosyl moiety to 2′-hydroxy of at least nine flavonoids to yield six new *** of the 2′-O-glycosides showed noticeable inhibitory activities against cyclooxygenase *** crystal structure of UGT71AP2(2.15Å)was solved,and mechanisms of its regio-selectivity was interpreted by pKa calculations,molecular docking,MD simulation,MM/GBSA binding free energy,QM/MM,and hydrogen‒deuterium exchange mass spectrometry *** structure-guided rational design,we obtained the L138T/V179D/M180T mutant with remarkably enhanced regio-selectivity(the ratio of 7-O-glycosylation byproducts decreased from 48%to 4%)and catalytic efficiency of 2′-O-glycosylation(kcat/Km,0.23 L/(s·μmol),12-fold higher than the native).Moreover,UGT71AP2 also possesses moderate UDP-dependent de-glycosylation activity,and is a dual function *** work provides an efficient biocatalyst and sets a good example for protein engineering to optimize enzyme catalytic features through rational design.

关键词： Glycosyltransferase Regio-selectivity Crystal structure De-glycosylation Catalytic mechanisms

The materials genome and CALPHAD

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Chinese Science Bulletin 2014年第15期59卷 1635-1640页

作者： John gren Materials Science and Engineering The Royal Institute of Technology

The mapping of the human genome is an important basis for the development of new medicals and medical ***,it has attracted tremendous research funding over the last *** June2011,the Materials Genome Initiative was announced by the US President Obama as collaboration on modeling and advanced materials ***,the materials genome was given a rather vague definition in the ***,the materials genome should be defined in analogy with biological genomes and one may then conclude that:at any moment,the performance of a specific material depends on its chemical composition(inherent property stored in its genome)and its environment(external interactions–processing–conditions during usage).The materials genome should thus be defined as a set of information encoded in the language of thermodynamics obtained by careful assessment of experimental data and quantum mechanical calculations from which certain conclusions about the material can be *** CALPHAD databases contain the thermodynamic and kinetic properties of a materials *** databases allow the prediction of materials structure as well as its response to processing and usage conditions,and are major parts of integrated computational materials engineering.

关键词：材料数据库人类基因组相图计算量子力学计算基因组计划动力学性质科研经费美国总统

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No trade-off between trichome production and tolerance to leaf and inflorescence damage in a natural population of Arabidopsis lyrata

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Journal of Plant Ecology 2014年第4期7卷 373-383页

作者： Adriana Puentes JonÅgren Department of Plant Ecology and Evolution Evolutionary Biology Centre(EBC)Uppsala UniversityNorbyvägen 18DSE-75236 UppsalaSweden

Aims Early models of plant defense conceived resistance and tolerance to herbivore damage as mutually exclusive *** for this idea has been equivocal and studies on these two strategies are still needed to understand the evolution of defenses in natural *** Arabidopsis lyrata,the production of trichomes,a documented resistance trait,has been associated with a fitness cost in the absence of *** examined whether trichome production is also associated with reduced tolerance to simulated herbivore *** We conducted a field experiment in a natural swedish population of *** where we inflicted leaf(0 vs.50%of the area of each leaf removed)and inflorescence damage(0 vs.50%of inflores-cences removed)to trichome-producing and glabrous plants in a factorial *** examined the response(survival,growth and reproduction)of the plants to the imposed damage over 2 *** Findingstrichome-producing plants were not less tolerant than glabrous plants to simulated herbivore damage(no significant morph×leaf damage or morph×inflorescence damage interactions).Inflorescence and leaf damage had independent negative effects on the performance of damaged *** damage reduced rosette size the year of damage,but effects on reproductive output in the year of damage,and on survival and reproductive performance the following year were weak and not statistically *** damage significantly reduced the number of flowers,fruits and seeds the year of damage,but not in the following *** of morph,the study population was more tolerant to leaf than to inflorescence *** results indicated no trade-off between trichome production and tolerance,suggesting that these two defense mechanisms have the potential to evolve indepen-dently in this *** population.

关键词： plant defense fitness costs resistance traits defoliation florivory

Comparative study using MS and XRD of Fe_(80)Al_(20) alloy produced by mechanical alloying

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Science China(Physics,Mechanics & Astronomy) 2013年第8期56卷 1504-1507页

作者： HADEF F. OTMANI A. grenèCHE J.M. Laboratoire de Recherche sur la Physico-Chimie des Surfaces et Interfaces LRPCSIUniversité 20 Ao t 1955BP 26Route d'El-HaddaiekSkikda 21000Algérie LUNAM Université du MaineInstitut des Molécules et Matériaux du MansIMMM UMR CNRS 628372085 Le MansFrance

An X-ray diffraction and 57Fe MOssbauer effect study of mechanically alloyed Fe80Al20 is presented. X-ray measurements indicate that the disordered bcc α-Fe（A1） solid solution was formed after 2 h of milling, while the analysis of Mrssbauer spectra suggested that total dissolution of aluminium is achieved after 10 h of milling. These differences can be attributed to：（i） rapid nanocrystallization of aluminium and/or （ii） small particles with small amounts of aluminium cannot be detected by the X-ray diffraction technique.

关键词： nanostructured materials Fe-AI alloys mechanical alloying X-ray diffraction M6ssbauer spectrometry

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Recent research progress for upconversion assisted dye-sensitized solar cells

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Chinese Chemical Letters 2021年第6期32卷 1834-1846页

作者： Xugeng Guo Wenpeng Wu Yuanyuan Li Jinglai Zhang Li Wang Hans Ågren Institute of Upconversion Nanoscale Materials College of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475004China Henan Center for Outstanding Overseas Scientists Henan UniversityKaifeng 475004China Department of Physics and Astronomy Uppsala UniversityBox 516SE-75120 UppsalaSweden

Upconversion(UC)technology makes it possible to harvest infrared(IR)light from the sun and has increasingly been employed in recent years to improve the efficiency of solar *** progress in the area concerns both research on fundamental principles and processes of UC and technologies of device *** increase of important solar cell parameters,like short-circuit photocurrent density and open-circuit photovoltage as well as the total photon-to-current efficiency,has been *** here review the research published during the last few years in the area,in particular we consider the two most cherished techniques,namely the incorporation of upconverting nanophosphors directly into the photoanodes of the solar cells and the introduction of plasmonic metal nanoparticles co-existing with the UC *** ways to achieve strong field enhancement,and the use of the non-linear nature of UC,is to apply microlenses,with or without assisting plasmonic *** enhanced UC action has been demonstrated by broad band and effective harvesting by organic IR antennas,with subsequent mediation by an intermediate nanoshell of the energy into the upconverting ***,nanohybrid and layer-by-layer technologies involving upconverting particles as well as the use of upconverting nanoparticles in hole-transport and electrolyte layers,tested in recent works,are also *** most of these technologies employ upconverting rare earth metals for sequential photon absorption,the main alternative technique,namely triplet-triplet annihilation UC using organic materials,is also *** is our belief that all these approaches will be further much researched in the near future,with potentially great impact on solar cell technology.

关键词： Upconversion nanoparticles Dye-sensitized solar cells Infrared light Triplet-triplet annihilation Photovoltaic systems

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Portal vein thrombosis:Prevalence,patient characteristics and lifetime risk:A population study based on 23796 consecutive autopsies

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World Journal of Gastroenterology 2006年第13期12卷 2115-2119页

作者： Mats gren David Bergqvist Martin Bjrck Stefan Acosta Henry Eriksson Nils H Sternby Department of Vascular Surgery Uppsala University Hospital UppsalaSweden Departments of Vascular Diseases and Pathology Lund University Malm University HospitalMalmSweden Department of Medicine Sahlgrenska University Hospital/stra GteborgSweden Departments of Vascular Diseases and Pathology Lund University MalmUniversity HospitalMalmSweden

AIM： TO assess the lifetime cumulative incidence of portal venous thrombosis （PVT） in the general population. METHODS： Between 1970 and 1982, 23 796 autopsies, representing 84% of all in-hospital deaths in the Malmo city population, were performed, using a standardised protocol including examination of the portal vein. PVT patients were characterised and the PVT prevalence at autopsy, an expression of life-time cumulative incidence, assessed in high-risk disease categories and expressed in terms of odds ratios and 95% CI. RESULTS： The population prevalence of PVT was 1.0%. Of the 254 patients with PVT 28% had cirrhosis, 23% primary and 44% secondary hepatobiliary malignancy, 10% major abdominal infectious or inflammatory disease and 3% had a myeloproliferative disorder. Patients with both cirrhosis and hepatic carcinoma had the highest PVT risk, OR 17.1 （95% CI 11.1-26.4）. In 14% no cause was found; only a minority of them had developed portal-hypertension-related complications. CONCLUSION： In this population-based study, PVT was found to be more common than indicated by previous clinical series. The markedly excess risk in cirrhosis and hepatic carcinoma should warrant an increased awareness in these patients for whom prospective studies of directed intervention might be considered.

关键词： Epidemiology Venous thrombosis Portal hypertension Cirrhosis Gastrointestinal cancer