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Synthesis, Characterization and Crystal Structure of Quaternary Complex of Gadolinium (Ⅲ)

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Journal of Rare Earths 2003年第1期21卷 9-12页

作者：朱龙观蔡国强王国平北川进正冈重行 department of chemistry Zhejiang University Dep artment of Synthetic chemistry and biological chemistry Faculty of Engineering Dep artment of Synthetic chemistry and biological chemistry Faculty of Engineering Kyoto University

A new quaternary mixed anion complex of gadolinium(Ⅲ), [Gd(CH 3CH 2COO) 2(N O 3)(phen)] 2, was synthesized and structurally characterized. The ESR spectr um of the complex with effective g values of 5.314, 2 473 and 1.880 in poly crys talline powder at room temperature is quite different from the U spectrum. The c oordination number of Gd 3+ is nine with a monocapped square antiprism geom etry. And the stacking effect was observed in the complex. The crystal of the co mplex belongs to triclinic with space group P 1, a=0.9626(4) n m, b=0.9732(4) nm, c=1.1758(5) nm, α=102.45(1)°, β=108.16(1) °, γ=96.68(2)°, V=1.0018(7) nm3, Z=2, D c=1.80 g·cm -3 , μ(MoKα)=33.63 mm -1, F(000)=530, GOF=1.80, R=0.023 and R w=0.027.

关键词： organic chemistry gadolinium(Ⅲ) crystal s tructure mixed ligands ESR quaternary complex rare earths

Orientation of larval and juvenile horseshoe crabs Limulus polyphemus to visual cues: Effects of chemical odors

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Current Zoology 2010年第5期56卷 618-633页

作者： Julie M.MEDINA Richard A.TANKERSLEY department of biological sciences Florida Institute of Technology

Adult horseshoe crabs Limulus polyphemus have long served as models for the study of vision in marine arthropods. Yet, little is known about the ability of early life history stages to detect and respond to visual cues. We examined the visually directed movements of larvae and first stage juveniles to horizons containing dark visual targets of different sizes. The study tested the hypotheses that （1） larval and juvenile crabs can detect and respond to visual targets and （2） the direction of orientation varies with the presence of chemical cues associated with settlement habitats. Orientation of larval and juvenile crabs to rectangles subtending angles from 30--330~ was tested in a circular arena containing water that either lacked estuarine chemical cues （offshore water） or contained odors from aquatic vegetation or known predators. In the absence of chemical odors, larvae oriented toward and juveniles moved away from dark horizons subtending angles 〉 60~. When placed in water containing chemical odors from potential nursery habitats, including the seagrasses Halodule wrightii and Syringodium filiforme, crabs reversed their direction of orientation relative to their responses in offshore water. Odors from two known predators, the mummichug Fundulus grandis and blue crab Callinectes sapidus, had no affect on the orientation of larvae. Yet, juveniles responded to both odors by moving toward the visual target. Results support the hypothesis that the visual orientation of larval and juvenile horseshoe crabs changes upon exposure to habitat and predator cues and that the direction of the response undergoes an ontogenetic shift following metamorphosis

关键词： Orientation Visual cues Chemical odors

Phylogenetic reconstruction of Chirita and allies (Gesneriaceae) with taxonomic treatments

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Journal of Systematics and Evolution 2011年第1期49卷 50-64页

作者： James F. SMITH department of biological sciences Boise State University

Chirita D. Don, a large genus in the subfamily Cyrtandroideae of Gesneriaceae, has been the subject of much debate whether it is a natural group or not. In addition, the highly heterogeneous Chirita has also been very problematic with regard to delimitation and subdivision. Here we used the nrDNA internal transcribed spacer and cpDNA trnL-F for molecular phylogenetic analaysis, combined with morphological data. Our results suggest that Chirita is an artificial, polyphyletic genus. The most important character that defines Chirita, the dorso-ventrally oblique and bilamellar stigma, has evolved convergently in different clades of diandrous Cyrtandroideae. Chirita sensu stricto only includes the species of Chirita sect. Chirita, whereas Chirita sect. Microchirita is an independent clade located at the basal node of the phylogenetic tree. Chirita sect. Liebigia is closely related to Didymocarpus with an entire stigma unlike other species of Chirita. The species of Chirita sect. Gibbosaccus, Chiritopsis, Primulina, and Wentsaiboea form a monophyletic group that is sister to a strongly supported clade comprising four monotypic genera Paralagarosolen, Calcareoboea, Petrocodon, and Tengia. We further analyzed the morphological evolution of Chirita and identified a series of morphological synapomorphies for the monophyletic groups revealed herein, and thereby provide a taxonomic treatment in this study.

关键词： Chirita D. Don morphological evolution phylogenetic reconstruction polyphyly taxonomic treatment.

Rational modulation of fluorophosphate cathode by anionic groups to reduce the polarization behavior for fast-charging sodium-ion batteries

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Journal of Energy chemistry 2025年第1期100卷 509-521页

作者： Xinyuan Wang Fan Zhang Xingyu Zhou Qian Wang Changyu Liu Yangyang Liu Hui Wang Xiaojie Liu Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry & Materials Science Northwest University

Na3V2（PO4）2O2F （VP） is recognized as a promising cathode material for sodium-ion batteries due to its stable structural framework and high specific *** functional theory （DFT） and finite element simulations show that incorporating SO42-into VP decreases its band gap,lowers the migration energy barrier,and ensures a uniform Na+concentration gradient and stress distribution during charge and discharge ***,the average Na+diffusion coefficient of Na3V2（PO4）1.95（SO4）0.05O2F（VPS-1） is roughly double that of VP,leading to enhanced rate capability (80 C,75.5 mAh g-1) and cycling stability (111.0 mAh g-1capacity after 1000 cycles at 10 C current density) for ***-1 exhibits outstanding fast-charging capabilities,achieving an 80%state of charge in just 8.1 *** assembled VPS-1//SbSn/NPC full cell demonstrated stable cycling over 200 cycles at a high 5 C current,maintaining an average coulombic efficiency of 95.35%.

关键词： Anionic group modulation Polarization behavior Fast-charging Sodium-ion battery Fluorophosphate Cathode

Influence of elution conditions on DNA transport behavior in free solution by hydrodynamic chromatography

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Science China chemistry 2015年第10期58卷 1605-1611页

作者： Lei Liu Vijaykumar Veerappan Yuzhi Bian Guangsheng Guo Xiayan Wang Beijing Key Laboratory for Green Catalysis and Separation department of chemistry Engineering Beijing University of Technology department of biological sciences University of North Texas

We have previously developed bare narrow-bore capillary chromatography. In this work, high-performance DNA separation was realized for a size range of 10–800 base pairs(bp) utilizing bare narrow-bore capillary chromatography with 750 nm- radius capillaries. Separation behavior of double-stranded DNA(ds DNA) fragments was investigated over a range of eluent concentrations and elution pressures. DNA molecules were hydrodynamically separated in a size-dependent manner in free solution without any sieving matrices, with the longer fragments being eluted out from the capillary earlier. It was found that the eluent concentration variously influenced the transport behavior for different-sized DNA fragments depending upon the configuration of DNA molecules and the association of counterions. Ionic strength of the solutions strongly impacted DNA persistence length. Enhanced elution pressure could shorten analysis time with a slight loss in resolution. Excellent efficiency of two million theoretical plates per meter was achieved, which indicates the enormous potential of bare narrow-bore capillary chromatography for the analysis of DNA fragments. These findings would be useful in understanding the transport behavior of DNA fragments in confined dimensions for chromatography in free solution.

关键词： DNA separation transport behavior chromatography

From mice to humans:a need for comparable results in mammalian neuroplasticity

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Neural Regeneration Research 2025年第2期20卷 464-466页

作者： Marco Ghibaudi Enrica Boda Luca Bonfanti Neuroscience Institute Cavalieri Ottolenghi OrbassanoItaly department of Veterinary sciences University of TurinTurinItaly department of Neuroscience Rita Levi-Montalcini University of TurinTurinItaly

Brain plasticity-A universal tool with many variations:The study of brain plasticity has been gaining interest since almost a century and has now reached a huge amount of information(>80,000 results in PubMed).Overall,different types of plasticity,including stem cell-driven genesis of new neurons(adult neurogenesis),cells in arrested maturation(dormant neurons),neuro-glial and synaptic plasticity,can coexist and contribute to grant plastic changes in the brain,from a cellular to system level(Benedetti and Couillard-Despres,2022;Bonfanti et al.,2023).

关键词： plasticity al. arrest

Utilizing engineered extracellular vesicles as delivery vectors in the management of ischemic stroke:a special outlook on mitochondrial delivery

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Neural Regeneration Research 2025年第8期20卷 2181-2198页

作者： Jiali Chen Yiyang Li Xingping Quan Jinfen Chen Yan Han Li Yang Manfei Zhou Greta Seng Peng Mok Ruibing Wang Yonghua Zhao Institute of Chinese Medical sciences State Key Laboratory of Quality Research in Chinese MedicineUniversity of MacaoTaipaMacao Special Administrative RegionChina department of Pharmacy Hunan Provincial People’s Hospitalthe First Affiliated Hospital of Hunan Normal UniversityChangshaHunan ProvinceChina department of Electrical and Computer Engineering University of MacaoTaipaMacao Special Administrative RegionChina department of Pharmaceutical sciences Faculty of Health SciencesUniversity of MacaoTaipaMacao Special Administrative RegionChina

Ischemic stroke is a secondary cause of mortality worldwide,imposing considerable medical and economic burdens on *** vesicles,serving as natural nanocarriers for drug delivery,exhibit excellent biocompatibility in vivo and have significant advantages in the management of ischemic ***,the uncertain distribution and rapid clearance of extracellular vesicles impede their delivery *** utilizing membrane decoration or by encapsulating therapeutic cargo within extracellular vesicles,their delivery efficacy may be greatly ***,previous studies have indicated that microvesicles,a subset of large-sized extracellular vesicles,can transport mitochondria to neighboring cells,thereby aiding in the restoration of mitochondrial function post-ischemic *** extracellular vesicles have also demonstrated the capability to transfer mitochondrial components,such as proteins or deoxyribonucleic acid,or their sub-components,for extracellular vesicle-based ischemic stroke *** this review,we undertake a comparative analysis of the isolation techniques employed for extracellular vesicles and present an overview of the current dominant extracellular vesicle modification *** the complex facets of treating ischemic stroke,we also delineate various extracellular vesicle modification approaches which are suited to different facets of the treatment ***,given the burgeoning interest in mitochondrial delivery,we delved into the feasibility and existing research findings on the transportation of mitochondrial fractions or intact mitochondria through small extracellular vesicles and microvesicles to offer a fresh perspective on ischemic stroke therapy.

关键词： delivery engineering extracellular vesicles identification ischemic stroke isolation mitochondria targeting strategy therapeutic effects

Cross-sectional study and spatial distribution of schistosomiasis among children in Northeastern Nigeria

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Asian Pacific Journal of Tropical Biomedicine 2016年第6期6卷 477-484页

作者： Robert Soumay Houmsou Sam Mao Panda Sambo Obadiah Elkanah Liatu Columbus Garba Binga Emmanuel Wama Elizabeth Une Amuta Santaya Larit Kela department of biological sciences Taraba State University biological sciences Programme Abubakar Tafawa Balewa University department of biological sciences University of Agriculture department of biological sciences Federal University Kashere

Objective: To determine schistosomiasis level and risk factors that exposed school-aged children to infection as well as to model schistosomiasis map in relation to altitude and rainfall in Gashaka Local Government Area, Taraba State, ***: The study was conducted between January 2014 and June 2014. Urine and faecal samples were collected from 1 080 school-aged children and processed using the filtration and formol–ether concentration techniques, ***: Irrespective of the schistosomes species, a point prevalence of 10.18% was reported out of the 1 080 children examined. Males were significantly infected than their female counterparts(11.75% vs. 8.43%)(χ2= 4.86; P = 0.027), as well as children aged6–10(11.65%, 72/618) and 11–15 years(10.29%, 35/340) than the other age groups(χ2= 9.274; P = 0.026). No significant difference was observed in schistosomiasis between children whose parents were educated(11.11%, 57/513) and not educated(9.88%,53/536)(χ2= 1.342; P = 0.247) and those whose parents are farmers(9.74%, 53/544) and non-farmers(10.63%, 57/536)(χ~2= 0.787; P = 0.375). Proximity to water bodies(distance < 500 m)(odds ratio = 1.809, confidence interval = 1.057–3.094; P = 0.003 1)and fishing(odds ratio = 2.632, confidence interval = 1.397–4.958; P = 0.003) were the risk factors exposing children to infection. The spatial distribution pattern of schistosomiasis showed that the infection was significantly higher in Serti A(22.2%, 26/180) and Mayo-Selbe(21.1%, 38/180) than the other localities(χ~2= 92.99; P = 0.000).Conclusions: This study reported a moderate level of infection among school-aged children with proximity to water bodies and fishing as the main risk factors. The spatial distribution of schistosomiasis in the area will guide in efficient and effective control programmes at local level. It is recommended that continued efforts be made to scale-up distribution of praziquantel to high risk areas so as to curb the progression of the d

关键词： Spatial Schistosomiasis Gashaka Taraba State Nigeria

Accurate simulation of surfaces and interfaces of ten FCC metals and steel using Lennard–Jones potentials

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npj Computational Materials 2021年第1期7卷 205-219页

作者： Krishan Kanhaiya Seonghan Kim Wonpil Im Hendrik Heinz department of Chemical and biological Engineering University of Colorado at BoulderBoulderCO 80301USA departments of biological sciences Chemistryand BioengineeringLehigh UniversityBethlehemPA 18015USA

The earlier integration of validated Lennard–Jones(LJ)potentials for 8 fcc metals into materials and biomolecular force fields has advanced multiple research fields,for example,metal–electrolyte interfaces,recognition of biomolecules,colloidal assembly of metal nanostructures,alloys,and *** we introduce 12-6 and 9-6 LJ parameters for classical all-atom simulations of 10 further fcc metals(Ac,Ca(α),Ce(γ),Es(β),Fe(γ),Ir,Rh,Sr(α),Th(α),Yb(β))and stainless *** parameters reproduce lattice constants,surface energies,water interfacial energies,and interactions with(bio)organic molecules in 0.1 to 5%agreement with experiment,as well as qualitative mechanical properties under standard *** are reduced up to a factor of one hundred in comparison to earlier Lennard–Jones parameters,embedded atom models,and density functional *** also explain a quantitative correlation between atomization energies from experiments and surface energies that supports parameter *** models are computationally very efficient and applicable to an exponential space of *** with a wide range of force fields such as the Interface force field(IFF),AMBER,CHARMM,COMPASS,CVFF,DREIDING,OPLS-AA,and PCFF enables reliable simulations of nanostructures up to millions of atoms and microsecond time ***-friendly model building and input generation are available in the CHARMM-GUI Nanomaterial *** a limitation,deviations in mechanical properties vary and are comparable to DFT *** discuss the incorporation of reactivity and features of the electronic structure to expand the range of applications and further increase the accuracy.

关键词： steel metals qualitative