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Spatial and temporal gradients in the rate of dust deposition and aerosol optical thickness in southwestern Iran

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Journal of Arid Land 2021年第1期13卷 1-22页

作者： Mansour A FOROUSHANI Christian OPP Michael GROLL Department of Geography Philipps-Universität MarburgMarburg 35037Germany

the southwestern Iran is one of the regions that are most prone to dust *** objective of this study is the analysis of the spatial and temporal distributions of dust deposition rate as a key factor for finding the relative impact of the ***,the monthly mean aerosol optical thickness(AOt)from Moderate Resolution Imaging Spectroradiometer(MODIS)was analyzed and compared with the dust amount variations from ground deposition rate(GDR),and the results were further used to investigate the spatial and temporal distributions of dust events in southwestern Iran for the period between 2014 and *** air mass trajectories,using the Hybrid Single-Particle Lagrangian Integrated trajectory(HYSPLIt)model,were proven to be a discriminator of their local and regional *** results from GDR analysis produced a correlation coefficient between dust event history and deposition rates at dust magnitudes of>0.93 that is meaningful at the 95%confidence ***,the deposition rates varied from 3 g/m2 per month in summer to 10 g/m2 per month in spring and gave insight into the transport direction of the *** the same time series,AOt correspondences with MODIS on terra in four aerosol thickness layers(clean,thin,thick,and strong thick)were shown in relation to each *** deepest mixed layers were observed in spring and summer with a thickness of approximately 3500 m above ground level in the study *** of ground-based observations were correlated with the same variations for each aerosol thickness layer from MODIS images and they can be applied to discriminate layers of aeolian dust from layers of other ***,dust distribution plots from AOt participated to enhance mass calculations and estimation deposition rates from the thick and strong thick aerosol thickness layers using the results from *** all the advances of AOt,under certain circumstances,ground-based observations are better able to represent aerosol co

关键词： aerosol optical thickness ground deposition rate HYSPLIt dust deposition Iran

Cluster Chemistry with(Pseudo-)tetrahedra Involving Group 13-15(Semi-)Metal Atoms

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CCS Chemistry 2022年第3期4卷 809-824页

作者： Fuxing Pan Lukas Guggolz Stefanie Dehnen Fachbereich Chemie and Wissenschaftliches Zentrum für Materialwissenschaften Philipps-Universität Marburg35043 Marburg

Compounds containing(pseudo-)tetrahedral main group(semi-)metal units are fundamentally important in three ***,they provide new strategies for the stabilization of tetrahedral units,such as Pn_(4)(Pn=P,As)and their isoelectronic analogs,in the coordination sphere of d-/f-block metal ***,they serve as first-step models for the activation of tetrahedral ***,they are starting materials for subsequent transformations toward larger clusters or *** or full isoelectronic replacement of the pnictogen atoms in P4 or As_(4) results in a variety of(pseudo-)tetrahedral anions,tt_(4)^(4−)(tt=Si,Ge,Sn,Si/Ge),(Ge_(3)Pn)^(3−)(Pn=P,As;formed in situ),(tt_(2)Pn_(2))^(2−)(tt/Pn=Ge/P,Ge/As,Sn/Sb,Sn/Bi,Pb/Sb,Pb/Bi),or(trBi_(3))^(2−)(tr=Ga,In,tl),and also cations,(P3Ch)+(Ch=S,Se,te).the anions have proven to be excellent starting materials and building blocks for multinary clusters in the context of Zintl *** compounds,which push forward the boundary of intriguing P4 chemistry,have never been thoroughly summarized *** this minireview,we introduce all known intact(pseudo-)tetrahedral group 13–15 units,as well as the coordination compounds based on them,along with two new missing links,[Au(η^(2-)tt_(2)Bi_(2))_(2)]^(3−)(tt=Sn,Pb).

关键词： tetrahedra coordination compounds group 13-15(semi-)metals Zintl anions gold

Deletions in the genomes of fifteen inbred mouse lines and their possible implications for fat accumulation

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第11期8卷 777-781页

作者： SCHMItt Armin O. DEMPFLE Astrid BROCKMANN Gudrun A. Institute for Animal Sciences Humboldt-Universitt zu Berlin Invalidenstraβe 42 10115 Berlin Germany Institute for Medical Biometry and Epidemiology Phillips-Universitt Marburg Bunsenstraβe 3 35037 Marburg Germany

Copy number variants (CNVs) are pieces of genomic DNA of 1000 base pairs or longer which occur in a given genome at a different frequency than in a reference genome. their importance as a source for phenotypic variability has been recognized only in the last couple of years. Chromosomal deletions can be seen as a special case of CNVs where stretches of DNA are missing in certain lines when compared to the reference genome of the mouse line C57BL/6, for example. Based upon more than 8 million single nucleotide polymorphisms (SNPs) in the fifteen inbred mouse lines which were determined in a whole genome chip based resequencing project by Perlegen Sciences, we detected 20166 such long chromosomal deletions. they cover altogether between 4.4 million and 8.8 million base pairs, depending on the mouse line. thus, their extent is comparable to that of SNPs. the chromosomal deletions were found by searching for clusters of missing values in the genotyping data by applying bioinformatics and biostatistical methods. In contrast to isolated missing values, clusters are likely the consequence of missing DNA probe rather than of a failed hybridization or deficient oligos. We analyzed these deletion sites in various ways. twenty-two percent of these deletion sites overlap with exons; they could therefore affect a gene's functioning. the corresponding genes seem to exist in alternative forms, a phenomenon that reminds of the alternative forms of mRNA generated during gene splicing. We furthermore detected statistically significant association between hundreds of deletion sites and fat weight at the age of eight weeks.

关键词： Copy number variants (CNVs) Chromosomal deletions Single nucleotide polymorphisms (SNPs) Resequencing Cluster analysis Association between genotype and phenotype

A MoClo-Compatible toolbox of ECF Sigma Factor-Based Regulatory Switches for Proteobacterial Chassis

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BioDesign Research 2024年第1期6卷 1-19页

作者： Doreen Meier Christian Rauch Marcel Wagner Paul Klemm Patrick Blumenkamp Raphael Müller Eric Ellenberger Kinnari M.Karia Stefano Vecchione Javier Serrania Marcus Lechner Georg Fritz Alexander Goesmann Anke Becker Center for Synthetic Microbiology(SYNMIKRO)and Department of Biology Philipps-Universität MarburgMarburgGermany Bioinformatics and Systems Biology Justus-Liebig-Universität GiessenGiessenGermany the University of Western Australia School of Molecular SciencesPerthAustralia

the construction of complex synthetic gene circuits with predetermined and reliable output depends on orthogonal regulatory parts that do not inadvertently interfere with the host machinery or with other circuit ***,extracytoplasmic function sigma factors(ECFs),a diverse group of alternative sigma factors with distinct promoter specificities,were shown to have great potential as context-independent regulators,but so far,they have only been used in a few model ***,we show that the alphaproteobacterium Sinorhizobium meliloti,which has been proposed as a plant-associated bacterial chassis for synthetic biology,has a similar phylogenetic ECF acceptance range as the gammaproteobacterium Escherichia coli.A common set of orthogonal ECF-based regulators that can be used in both bacterial hosts was identified and used to create 2-step delay *** genetic circuits were implemented in single copy in *** by chromosomal integration using an established method that utilizes bacteriophage *** ***,we demonstrated the usability of single-copy pABC plasmids as equivalent carriers of the synthetic *** circuits were either implemented on a single pABC or modularly distributed on 3 such *** addition,we provide a toolbox containing pABC plasmids compatible with the Golden Gate(MoClo)cloning standard and a library of basic parts that enable the construction of ECF-based circuits in *** and in *** work contributes to building a context-independent and species-overarching ECF-based toolbox for synthetic biology applications.

关键词： toolbox sigma chassis compatible factor-based moclo proteobacterial regulatory switches

Monitoring of central corneal thickness after phacoemulsification—comparison of statical and rotating Scheimpflug pachymetry,and spectral-domain OCt

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International Journal of Ophthalmology(English edition) 2022年第8期15卷 1266-1272页

作者： Daniel M.Handzel Carsten H.Meyer Alfred Wegener Augenaerzte im Altstadt-Carree Fulda 36037Germany University Eye Hospital Philipps-UniversitätMarburg 35032Germany University Eye Hospital Rheinische Friedrich-WilhelmsUniveritätBonn 53124Germany

AIM:to explore the possibility of deploying three contactless devices(static and rotating Scheimpflug technology,spectral domain optical coherence tomography)for measuring central corneal thickness(CCt)in preoperative and postoperative examinations of cataract ***:totally 72 patients who had undergone surgery without complications were *** CCt was measured prior to the operation,as well as on the first,5th-7th and 28th day following the operation using the Nidek Nt 530-P,Sirius?,and topcon OCt-2000 ***:A significant postoperative increase and subsequent decrease in CCt was identified with all three *** correlations were highly significant and thus reflect a very good degree of comparability at all times with the exception of the rotating Scheimpflug *** postoperative results from the latter differed significantly from the other *** correlations were Sirius/topcon(P=0.010)and Sirius/Nidek(Ptatistically significant difference could be identified in the comparison between topcon and Nidek(P=0.056).CONCLUSION:All three devices are suitable for postoperative monitoring of *** measurement results are only comparable to a limited extent and not interchangeable in the course of treating a single *** is due to the different imaging technology used in the devices and the resulting modalities for conducting the measurements.

关键词： cataract surgery pachymetry corneal thickness Scheimpflug imaging optical coherence tomography

Hyper Gravity-Induced transients in <i>Phycomyces</i>as Measured by Single Beam Spectrophotometer on the Sounding Rocket tEXUS 50

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Journal of Modern Physics 2018年第2期9卷 273-286页

作者： Werner Schmidt Fachbereich Biologie Philipps-Universit&auml t marburg Marburg Germany Fachbereich Biologie Universit&auml t Konstanz Konstanz Germany

In the first paper of two referring to the tEXUS 50 campaign using micro dual wavelength spectrometers (MDWS) we kinetically determined the threshold1 for GIACs (gravity-induced absorption changes) in Phycomyces to be lower than 25 × 10−3 g (http://***/pdf/JMP_***). In this second paper, we attended measurement of GIAC-spectra. Unexpectedly, during the upwards movement, i.e. the hypergravity phase up to top acceleration values reaching 11.6 g at 35.4 s after liftoff we observed transient GIAC-spectra ranging from 380 to 750 nm. In addition, during the whole acceleration phase of 68.2 s, another component near 700 nm develops which remains stable during the whole “free fall trajectory parabola” for 381.3 s. the subsequent reentry of the rocket leads to extraordinary deceleration values up 37.8 g, completely destroying Phycomyces sporangiophores excluding their spectral measurement. During the microgravity phase and by centrifuge operation we were unable to detect any GIAC-spectra (in contrast to kinetic MDWS-measurements, first paper).

关键词： MDWS (Micro-Dual Wavelength Spectrophotometer) Single Beam Spectrophotometer (SBS) Diode Array Spectrometer (USB-2000+ Ocean Optics) GIAC (Gravity-Induced Absorption Change) Phycomyces blakesleeanus Sporangiophore Micro- and Hypergravity texus 50 Sounding Rocket Graviperception. Hyper Gravity-Induced transients

Gravireception in <i>Phycomyces</i>: threshold Determination on the Sounding Rocket tEXUS 50

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Journal of Modern Physics 2015年第10期6卷 1381-1389页

作者： Werner Schmidt Fachbereich Biologie Philipps-Universit&#228 t marburg Marburg Germany Fachbereich Biologie Universit&#228 t Konstanz Konstanz Germany

Under parabolic flight conditions microgravity is not lower than 3 to 5 times 10-2 g. In contrast to parabolic flights, sounding rocket flights are virtually vibrational-free allowing microgravity as low as 10-5 g. thus, a rotating platform serving as centrifuge allows the precise generation of gravitational forces ranging from 5 to 100 mg (not possible during parabolic flights). On this basis we determined the threshold1 for optical reflection/absorption changes in Phycomyces to be lower than 25 × 10-3 g. this compares well with the threshold determination of gravitropism in Phycomyces on a clinostat centrifuge. Kinetics of gravity-induced absorption changes and gravity as generated by the on-board centrifuge do not coincide but show a distinctive hysteresis with a latency of 4 s (75 mg-ramp, pull-up).

关键词： MDWS (Micro-Dual Wavelength Spectrophotometer) Δ GIAC (Differential Gravity-Induced Absorption Change) Phycomyces blakesleeanus Sporangiophore Micro- and Hypergravity texus 50 Sounding Rocket Gravireception

Solid-State NMR Spectroscopic Study of Chromophore-Protein Interactions in the Pr Ground State of Plant Phytochrome A

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Molecular Plant 2012年第3期5卷 698-715页

作者： Chen Song Lars-Oliver Essen Wolfgang Ga＇rtner Jon Hughes J6rg Matysik Leids Instituut voor Chemisch Onderzoek Universiteit Leiden PO Box 9502 2300 RA Leiden The Netherlands Fachbereich Chemie Philipps-Universita＇t Marburg Hans-Meerwein-Stral3e D-35032 Marburg Germany Max-Planck-lnstitut for Bioanorganische Chemie StiftstraBe 34-36 D-45470 MCu＇lheim an der Ruhr Germany Pflanzenphysiologie Justus-Liebig-Universita＇t SenckenbergstraBe 3 D-35390 Giessen Germany

Despite extensive study, the molecular structure of the chromophore-binding pocket of phytochrome A （phyA）, the principal photoreceptor controlling photomorphogenesis in plants, has not yet been successfully resolved. Here, we report a series of two-dimensional （2-D） magic-angle spinning solid-state NMR experiments on the recombi- nant N-terminal, 65-kDa PAS-GAF-PHY light-sensing module of phytochrome A3 from oat （Avena sativa）, assembled with uniformly 13C- and lSN-labeled phycocyanobilin （u-[13C,15N]-***3）. the Pr state of this protein was studied regarding the electronic structure of the chromophore and its interactions with the proximal amino acids. Using 2-D 13C-13C and 1HJSN experiments, a complete set of 13C and 15N assignments for the chromophore were obtained. Also, a large number of 1H-13C distance restraints between the chromophore and its binding pocket were revealed by inter- facial heteronuclear correlation spectroscopy. 13C doublings of the chromophore A-ring region and the C-ring carbox- ylate moiety, together with the observation of two Pr isoforms, Pr-I and Pr-II, demonstrate the local mobility of the chromophore and the plasticity of its protein environment. It appears that the interactions and dynamics in the binding pocket of phyA in the Pr state are remarkably similar to those of cyanobacterial phytochrome （Cphl）. the N-terminus of the region modeled （residues 56-66 of phyA） is highly mobile. Differences in the regulatory processes involved in plant and Cphl phytochromes are discussed.

关键词： solid-state NMR plant phytochrome chromophore-protein interaction signal transduction

Regulation of cytochrome c oxidase contributes to health and optimal life

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World Journal of Biological Chemistry 2020年第2期11卷 52-61页

作者： Bernhard Kadenbach Department of Chemistry/Biochemistry Fachbereich ChemiePhilipps-Universität MarburgMarburg D-35043HessenGermany

the generation of cellular energy in the form of AtP occurs mainly in mitochondria by oxidative *** c oxidase(CytOx),the oxygen accepting and rate-limiting step of the respiratory chain,regulates the supply of variable AtP demands in cells by“allosteric AtP-inhibition of CytOx.”this mechanism is based on inhibition of oxygen uptake of CytOx at high AtP/ADP ratios and low ferrocytochrome c concentrations in the mitochondrial matrix via cooperative interaction of the two substrate binding sites in dimeric *** mechanism keeps mitochondrial membrane potentialΔΨm and reactive oxygen species(ROS)formation at low healthy *** signals increase cytosolic calcium leading to Ca^2+-dependent dephosphorylation of CytOx subunit I at the cytosolic side accompanied by switching off the allosteric AtPinhibition and monomerization of *** is followed by increase ofΔΨm and formation of ROS.A hypothesis is presented suggesting a dynamic change of binding of NDUFA4,originally identified as a subunit of complex I,between monomeric CytOx(active state with highΔΨm,high ROS and low efficiency)and complex I(resting state with lowΔΨm,low ROS and high efficiency).

关键词： Cytochrome c oxidase Regulation of respiration Allosteric AtP-inhibition NDUFA4 Reversible phosphorylation Efficiency of AtP synthesis Dimerization of cytochrome c oxidase