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Bacterial microcosms obey Taylor’s law:effects of abiotic and biotic stress and genetics on mean and variance of population density

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ecological Processes 2012年第1期1卷 77-82页

作者： Oliver Kaltz Patricia escobar-Páramo michael e hochberg Joel e Cohen Institut des Sciences de l’evolution UMR CNRS-UM2-IRD5554CC 065UniversitéMontpellier 2Place Eugène BataillonMontpellier Cedex 0534095France Centro Internacional de Física(CIF) Biotechnology GroupUniversidad Nacional de ColombiaCra 30 N°45-03BogotáDCColombia Laboratory of Populations Rockefeller and Columbia Universities1230 York AvenueBox 20New YorkNY10065-6399USA

Introduction:According to the empirical regularity called Taylor’s law,the variance of population density in samples of populations is a power of the mean population *** exponent is often between 1 and *** experiments investigated how genetics,evolution,and environment shape Taylor’s ***:Genetically different strains(wild type and hypermutator)of the bacterium Pseudomonas fluorescens evolved and were assayed under different environmental conditions(with and without antibiotic rifampicin and bacteriophage SBW252,separately and in combination).Results:experimental treatments altered the exponent b,but not the power law form,of the relation between variance and mean population *** populations treated only with rifampicin had a narrow range of mean population densities and exponent b=*** exposed to rifampicin plus phage had b=*** ancestral,control,and phage-exposed populations,mean abundance varied widely and b was not significantly different from *** factors(mutation rate,selection)and ecological factors(abiotic,biotic)jointly influenced ***:Taylor’s power law relationship accurately and robustly described variance as a function of mean population density,with overall exponent b=*** and other experiments with different factors acting on bacterial population size support the relevance of models that predict‘universal’patterns of fluctuation scaling.

关键词： Taylor’s law Pseudomonas fluorescens rifampicin bacteriophage genetics

Comparisons of oxbow lake fish assemblages in relation to bigheaded carp establishment in the lower White River, Arkansas

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ecological Processes 2024年第1期13卷 188-205页

作者： michael A.eggleton Cody J.Salzmann Joseph e.Kaiser Shannon C.F.Smith Department of Aquaculture and Fisheries University of Arkansas at Pine Bluff Arkansas Game and Fish Commission Virginia Institute of Marine Science

Background Since the late 1990s, bigheaded carps(largely silver carp [Hypophthalmichthys molitrix] but also bighead carp [H. nobilis]) have established throughout the lower Mississippi River basin. Using previously studied oxbow lakes in the lower White River basin, Arkansas, we compared current(2017, “post-carp” establishment) fish assemblages to historical(2002, “pre-carp” establishment) fish assemblages. Fish assemblages were comprehensively assessed using multiple gears, including boat electrofishing, mini-fyke nets, and experimental small-mesh gill *** T-tests suggested that fish assemblage indices of richness, diversity, evenness, and dominance were often greater(P e post-carp period as reflected by boat electrofishing and experimental gill nets. However, all indices were generally similar(P > 0.05) between the pre-carp and post-carp period with fish assemblages depicted using mini-fyke nets. Nonmetric multidimensional scaling analyses indicated that fish assemblages differed structurally between pre-carp and post-carp periods. Assemblage differences were linked to both small and large abundance changes for more than 20 species. Abundances of gizzard shad(Dorosoma cepedianum), emerald shiner(Notropis atherinoides), pugnose minnow(Opsopoeodus emiliae), crappies(Pomoxis spp.), bluegill(Lepomis macrochirus), orangespotted sunfish(L. humilis), and yellow bass(Morone mississippiensis) declined between the pre-carp and postcarp periods. Conversely, abundances of weed shiner(N. texanus), pallid shiner(Hybopsis amnis), longear sunfish(L. megalotis), buffalofishes(Ictiobus spp.), and gars(Lepisosteus spp.) generally increased during the same *** Although not possible to conclude assemblage shifts were entirely related to bigheaded carps due to the absence of an appropriate reference system where carps did not establish, the wide establishment of these carps is one of the most pervasive changes to have occurred in the lower White

关键词： Bigheaded carp Silver carp Aquatic nuisance species Fish assemblage Oxbow lake Large river

乡村地理学新视野:通过地理空间数据融合模拟乡村地域系统

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Science Bulletin 2024年第11期69卷 1590-1592页

作者： michael e.Meadows School of Geography and Ocean Science Nanjing UniversityNanjing 210023China Department of environmental and Geographical Science University of Cape TownRondebosch 7701South Africa

As nations worldwide strive to bridge the ever-expanding urban-rural divide,the rapid pace of urbanization has precipitated dramatic shifts in land use,population demographics,and the economy of rural areas[1,2].

关键词：乡村地理学 expanding 空间数据融合

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NeCAB family of neuronal calcium-binding proteins in health and disease

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Neural Regeneration Research 2025年第5期20卷 1236-1243页

作者： Diones Bueno michael K.e.Schafer Sudena Wang michael J.Schmeisser Axel Methner Institute for Molecular Medicine University Medical Center of the Johannes Gutenberg-UniversityMainzGermany Department of Anesthesiology University Medical Center of the Johannes Gutenberg-UniversityMainzGermany Institute of Anatomy University Medical Center of the Johannes Gutenberg-UniversityMainzGermany

The N-terminal eF-hand calcium-binding proteins 1–3(NeCAB1–3) constitute a family of predominantly neuronal proteins characterized by the presence of at least one eF-hand calcium-binding domain and a functionally less well characterized C-terminal antibiotic biosynthesis monooxygenase domain. All three family members were initially discovered due to their interactions with other proteins. NeCAB1 associates with synaptotagmin-1, a critical neuronal protein involved in membrane trafficking and synaptic vesicle exocytosis. NeCAB2 interacts with predominantly striatal G-protein-coupled receptors, while NeCAB3 partners with amyloid-β A4 precursor protein-binding family A members 2 and 3, key regulators of amyloid-β production. This demonstrates the capacity of the family for interactions with various classes of proteins. NeCAB proteins exhibit distinct subcellular localizations: NeCAB1 is found in the nucleus and cytosol, NeCAB2 resides in endosomes and the plasma membrane, and NeCAB3 is present in the endoplasmic reticulum and Golgi apparatus. The antibiotic biosynthesis monooxygenase domain, an evolutionarily ancient component, is akin to atypical heme oxygenases in prokaryotes but is not wellcharacterized in vertebrates. Prokaryotic antibiotic biosynthesis monooxygenase domains typically form dimers, suggesting that calcium-mediated conformational changes in NeCAB proteins may induce antibiotic biosynthesis monooxygenase domain dimerization, potentially activating some enzymatic properties. However, the substrate for this enzymatic activity remains uncertain. Alternatively, calcium-mediated conformational changes might influence protein interactions or the subcellular localization of NeCAB proteins by controlling the availability of protein–protein interaction domains situated between the eF hands and the antibiotic biosynthesis monooxygenase domain. This review summarizes what is known about genomic organization, tissue expression, intracellular localization, interac

关键词： calcium eF hand mitochondria nervous system signal transduction

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Prospective cohort study on facial profile changes in infants with Robin sequence and healthy controls

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World Journal of Pediatrics 2024年第6期20卷 581-589页

作者： Cornelia Wiechers Julian Sowula Karen Kreutzer Christoph e.Schwarz Christina Weismann michael Krimmel Christian F.Poets Bernd Koos Department of Neonatology Tuebingen University HospitalCalwerstrasse 772076 TuebingenGermany Center for Cleft Lip Palate and Craniofacial MalformationsTuebingen University HospitalTuebingenGermany Department of Orthodontics Tuebingen University HospitalTuebingenGermany Department of Oral and Maxillofacial Surgery Tuebingen University HospitalTuebingenGermany

Background Various conservative and surgical approaches exist to treat Robin sequence(RS),but their effects on facial profile and mandibular catch-up growth are unclear.A functional treatment concept,used in our centre for 25 years,includes an individualized palatal plate with a velo-pharyngeal extension and intensive feeding *** We performed a prospective study to objectively describe facial profiles in infants with RS treated with the above *** with isolated RS were admitted to our tertiary perinatal and national referral centre for craniofacial malformations between May 2018 and Nov *** with RS received 3D-photographs during clinically indicated *** controls were recruited from Dec 2018 to Sep 2019 and received 3D-photographs every 3 *** digitally measured jaw index(JI),defined as alveolar overjet(O)x maxillary arch(U)/mandibular arch(L),and the soft tissue reference points A’-point,Nasion’,B’-point angle(ANB’),describing the relative position of maxilla to mandible,were *** mixed models were used to examine time trajectories in JI and ANB’.Results A total of 2073D images,obtained in 19 infants with RS and 32 controls,were *** and ANB’decreased over time in both groups[for JI−0.18(95%CI−0.25 to−0.10);for ANB’:−0.40°per month[(95%CI−0.48 to−0.32)]]but remained lower in controls[for JI−2.5(95%CI−3.2 to−1.8);for ANB’-1.7°(95%CI−2.4 to−1.0)].Also,the ANB’model showed a significant effect of the interaction term diagnosis x *** Based on longitudinal 3D images,we describe changes in objective parameters of facial profile in infants with and without RS during the first year of *** findings indicate catch-up growth in infants treated for RS.

关键词： Infant Mandibular catch-up growth Pre-epiglottic Baton Plate Robin sequence Three-dimensional photography

The Formation of Oscillation Patterns Based on the Planetary Gravitational Field and Their Suitability for earthquake Prediction

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Journal of High energy Physics, Gravitation and Cosmology 2024年第1期10卷 149-157页

作者： michael e. Nitsche Z & S Institut Grosselfingen Germany

The fluctuating planetary gravitational field influences not only activities on the Sun but also on the earth. A special correlation function describes the harmonics of these fluctuations. Groups of earthquakes form oscillation patterns that differ significantly from randomly chosen control groups. These patterns are suitable as an element of an AI for the probability of earthquakes.

关键词： Planetary Gravitational Field earthquake Prediction AI

Neuronal trafficking as a key to functional recovery in immune-mediated neuropathies

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Neural Regeneration Research 2024年第11期19卷 2331-2332页

作者： Felix Kohle michael Schroeter Department of Neurology University of Cologne and University Hospital CologneCologneGermany

Immune-mediated neuropathies are rare diseases of the peripheral nervous system(PNS),substantially affecting patients’functionality and quality of *** are amenable to immunomodulatory treatments,which in many cases stabilize disease progression,but long-term deficits persist in many *** long-term deficits are particularly observed in monophasic autoimmune neuropathies like Guillain-Barrésyndrome and also in chronic variants,e.g.,chronic inflammatory demyelinating neuropathy(Fadia et al.,2019).

关键词： diseases autoimmune

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Odd-even effects in the structure and properties of aryl-substituted aliphatic self-assembled monolayers

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Nano Research 2024年第5期17卷 4231-4243页

作者： Piotr Cyganik Andreas Terfort michael Zharnikov Jagiellonian University Faculty of PhysicsAstronomy and Applied Computer ScienceSmoluchowski Institute of PhysicsŁojasiewicza 1130-348 KrakówPoland Institut für Anorganische und Analytische Chemie Universität FrankfurtMax-von-Laue-Straße 760438 FrankfurtGermany Applied Physical Chemistry Heidelberg UniversityIm Neuenheimer Feld 25369120 HeidelbergGermany

Self-assembled monolayers(SAMs)represent an important tool in context of nanofabrication and molecular engineering of surfaces and *** properties of functional SAMs depend not only on the character of the tail groups at the SAM-ambient interface,but are also largely defined by their *** its turn,the latter parameter results from a complex interplay of the structural forces and a variety of other factors,including so called odd-even effects,*** of the SAM structure and properties on the parity of the number(odd or even)of individual building blocks in the backbone of the SAM *** most impressive manifestation of the odd-even effects is the structure of aryl-substituted alkanethiolate SAMs on Au(111)and Ag(111),in which,in spite of the fact that the intermolecular interaction is mostly determined by the aryl part of the monolayers,one observes a pronounced dependence of molecular inclination and,consequently,the packing density of the SAM-forming molecules on the parity of number of methylene units in the alkyl *** we review the properties of the above systems as well as address fundamental reasons behind the odd-even effects,including the existence of a so-called bending potential,which is frequently disregarded in analysis of the structure-building *** generality of the odd-even effects in SAMs is additionally supported by the recent data for SAMs on GaAs,scanning tunneling microscopy data for SAMs on Ag(111),and the data for the monolayers with selenolate and carboxyl anchoring groups on Au(111)and Ag(111).The implications of these effects in terms of the control over the packing density and orientation of the tail groups at the SAM-ambient interface,structural perfection,polymorphism,temperature-driven phase transitions,and SAM stability toward such factors as ionizing radiation,exchange reaction,and electrochemical desorption are *** implications place the odd-even effects as an important tool

关键词： self-assembled monolayers molecular films surface and interface engineering odd-even-effects

Development of an active-site titrant for SARS-CoV-2 main protease as an indispensable tool for evaluating enzyme kinetics

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Acta Pharmaceutica Sinica B 2024年第5期14卷 2349-2357页

作者： Rabea Voget Julian Breidenbach Tobias Claff Alexandra Hingst Katharina Sylvester Christian Steinebach Lan Phuong Vu Renato H.Weiße Ulrike Bartz Norbert Sträter Christa e.Müller michael Gütschow Pharmaceutical Institute Pharmaceutical&Medicinal ChemistryUniversity of BonnBonn 53121Germany Institute of Bioanalytical Chemistry Center for Biotechnology and BiomedicineLeipzig UniversityLeipzig 04103Germany Department of Natural Sciences University of Applied Sciences Bonn-Rhein-SiegRheinbach 53359Germany

A titrant for the SARS-CoV-2 main protease(M^(pro))was developed that enables,for the first time,the exact determination of the concentration of the enzymatically active M^(pro) by active-site *** covalent binding mode of the tetrapeptidic titrant was elucidated by the determination of the crystal structure of the enzyme–titrant *** fluorogenic substrates of M^(pro),including a prototypical,internally quenched Dabcyl-eDANS peptide,were compared in terms of solubility under typical assay *** exploiting the new titrant,key kinetic parameters for the M^(pro)-catalyzed cleavage of these substrates were determined.

关键词： COVID-19 SARS-CoV-2 Main protease Peptide nitriles Fluorogenic substrates Active-site titration X-ray crystallography Inner filter effect