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Reactive oxygen species, nitric oxide and plant cell death associated with caspase-like protease activity during somatic embryogenesis in fraxinus mandshurica

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Journal of forestry Research 2022年第3期33卷 1005-1017页

作者： Hao Wang Dongyan Zhang Juan luis fernández-Lorenzo Hailong Shen Ling Yang State Key Laboratory of Tree Genetics and Breeding School of ForestryNortheast Forestry UniversityHarbin150040People’s Republic of China Crop Production Department High Polytechnique School of EngineeringSantiago de Compostela UniversityLugoSpain

Programmed cell death occurs in browning explants of fraxinus mandshurica during somatic embryogenesis, but the underlying mechanism is unclear. In this study, single cotyledons of zygotic embryos of f. mandshurica were used as explants. Mitochondrial structure and function, caspase-3-like protease activity, hydrogen peroxide metabolism, and nitric oxide accumulation induced by high concentrations of sucrose and plant growth regulators were studied. The results show that plant growth regulators induced somatic embryogenesis and also promoted explant browning. High sucrose concentrations had similar effects. High concentrations of sucrose and plant growth regulators led to the accumulation of hydrogen peroxide and nitric oxide which induced changes in mitochondrial structure and function such as modifications in mitochondrial morphology, increased membrane permeability, decreased membrane potential, and the release of cytochrome c into the cytoplasm. An increase in caspase-3-like protease activity triggered programmed cell death in some browning explant cells. During somatic embryogenesis there were increased activities of superoxide dismutase, peroxidase, and catalase, which are associated with hydrogen peroxide metabolism and jointly maintain reactive oxygen species levels. Intracellular nitric oxide synthase and nitrate reductase activities were not significantly correlated with nitric oxide content. Instead, intracellular nitric oxide may be derived from non-enzymatic reactions. Our results indicate that hydrogen peroxide and nitric oxide may function as signals, playing key roles in somatic embryogenesis and programmed cell death of explant cells of f. mandshurica. The interaction between nitric oxide and reactive oxygen species determines the occurrence of programmed cell death in explant cells;somatic embryogenesis and programmed cell death are positively regulated by hydrogen peroxide. However, the regulation of nitric oxide is complex.

关键词： Manchurian ash Somatic embryogenesis Programmed cell death Mitochondria Reactive oxide species Nitric oxide

Oxygen vacancies engineering by coordinating oxygen-buffering CeO_(2) with CoO_(x) nanorods as efficient bifunctional oxygen electrode electrocatalyst

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Journal of Energy Chemistry 2021年第8期30卷 615-625,I0013页

作者： Haihong Zhong luis Alberto Estudillo-Wong Yuan Gao Yongjun feng Nicolas Alonso-Vante State Key Laboratory of Chemical Resource Engineering Beijing Engineering Center for Hierarchical CatalystsCollege of ChemistryBeijing University of Chemical TechnologyNo.15 Beisanhuan East Road100029 BeijingChina IC2MP UMR-CNRS 7285University of PoitiersF-86022 Poitiers CedexFrance Departamento de Sociedad y Política Ambiental CIIEMADInstituto Politécnico NacionalCalle 30 de junio de 1520Alcaldía GAMC.P.07340 CDMXMexico Anqing Research Institute Beijing University of Chemical TechnologyNo.8 Huanhu West RoadHigh-Tech DistrictAnqing 24600China

CeO_(2)decorated CoOx rod-like hybrid,supported onto holey reduced graphene(CoOx/CeO_(2)/RGO)composite,was fabricated via a surfactant-assisted *** corresponding electrocatalytic performance towards oxygen reduction/evolution reactions(ORR and OER)was systematically investigated in alkaline ***,morphological and compositional studies revealed changes in electronic and surface properties when CeO_(2)was introduced as an oxygen buffer *** oxygen vacancies effectively enhanced the electrocatalytic activity,while the synergistic effect of co-catalyst CeO_(2),CoOx activecenters,and defective graphene with many voids facilitate the charge/mass transfer,making CoOx/CeO_(2)/RGO an efficient and stable bifunctional electrocatalyst for OER/ORR with△E=0.76 V(△E=E10mAcm.-2OER-E_(1/2).ORR).This parameter is 70 mV and 270 mV lower than CoOx/RGO and the benchmark Pt/C,*** addition,the OER/ORR bifunctionality of CoOx/CeO_(2)/RGO composite outperforms that of Pt/C catalyst in a H2-O_(2)micro fuel cell platform.

关键词： Co3O4 CeO_(2) Oxygen vacancies ORR OER

Splenic rupture following colonoscopy

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World Journal of Gastroenterology 2008年第41期14卷 6410-6412页

作者： Juan francisco Guerra Ignacio San francisco fernando Pimentel luis Ibanez Departamento de Cirugía Digestiva Pontificia Universidad Católica de Chile Marcoleta 367

Colonoscopy is a safe and routinely performed diagnostic and therapeutic procedure for different colorectal diseases. Although the most common complications are bleeding and perforation, extracolonic or visceral injuries have also been described. Splenic rupture is a rare complication following colonoscopy, with few cases reported. We report a 60-year-old female who presented to surgical consultation 8 h after a diagnostic colonoscopy. Clinical, laboratory and imaging findings were suggestive for a massive hemoperitoneum. At surgery, an almost complete splenic disruption was evident, and an urgent splenectomy was performed. After an uneventful postoperative period, she was discharged home. Splenic injury following colonoscopy is considered infrequent. Direct trauma and excessive traction of the splenocolic ligament can explain the occurrence of this complication. Many times the diagnosis is delayed because the symptoms are due to colonic insuffl ation, so the most frequent treatment is an urgent splenectomy. A high index of suspicion needs an early diagnosis and adequate therapy.

关键词： Colonoscopy Splenic injury Splenic rupture Splenectomy

Unclonable human-invisible machine vision markers leveraging the omnidirectional chiral Bragg diffraction of cholesteric spherical reflectors

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Light(Science & Applications) 2022年第11期11卷 2583-2601页

作者： Hakam Agha Yong Geng Xu Ma Deniz IsInsu Avsar Rijeesh Kizhakidathazhath Yan-Song Zhang Ali Tourani Hriday Bavle Jose-luis Sanchez-Lopez Holger Voos Mathew Schwartzo Jan P.f.Lagerwall University of Luxembourg Department of Physics&Materials Science1511 LuxembourgLuxembourg University of Luxembourg Interdisciplinary Centre for SecurityReliability and Trust(SnT)1855 LuxembourgLuxembourg University of Luxembourg University of LuxembourgDepartment of EngineeringL-1359 LuxembourgLuxembourg New Jersey Institute of Technology College of Architecture and DesignUniversity HeightsNewarkNJUSA

The seemingly simple step of molding a cholesteric liquid crystal into spherical shape,yielding a Cholesteric Spherical Reflector(CSR),has profound optical consequences that open a range of opportunities for potentially transformative *** chiral Bragg diffraction resulting from the helical self-assembly of cholesterics becomes omnidirectional in *** turns them into selective retroreflectors that are exceptionally easy to distinguish-regardless of background--by simple and low-cost machine vision,while at the same time they can be made largely imperceptible to human *** allows them to be distributed in human-populated environments,laid out in the form of QR-code-like markers that help robots and Augmented Reality(AR)devices to operate reliably,and to identify items in their *** the scale of individual CSRs,unpredictable features within each marker turn them into Physical Unclonable functions(PUfs),of great value for secure *** the machines reading them,CSR markers can thus act as trustworthy yet unobtrusive links between the physical world(buildings,vehicles,packaging...).and its digital twin computer *** opens opportunities to address pressing challenges in logistics and supply chain management,recycling and the circular economy,sustainable construction of the built environment,and many other fields of individual,societal and commercial importance.

关键词： spherical steric chiral

Targeted nanoparticles for the non-invasive detection of traumatic brain injury by optical imaging and fluorine magnetic resonance imaging

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Nano Research 2016年第5期9卷 1276-1289页

作者： luis Javier Cruz Ivo Que Markus Aswendt Alan Chan Mathias Hoehn Clemens Lowik Nanomedicine and Molecular Imaging Department of Radiology Leiden University Medical Center 2333ZA Leiden the Netherlands In-Vivo-NMR Laboratory Max Planck Institute for Neurological Research Cologne D-50931 Cologne Germany Percuros 7522NB Enschede the Netherlands

Necrosis is a form of cell death that occurs only under pathological conditions such as ischemic diseases and traumatic brain injury （TBI）. Non-invasive imaging of the affected tissue is a key component of novel therapeutic interventions and measurement of treatment responses in patients. Here, we report a bimodal approach for the detection and monitoring of TBI. PEGylated poly（lactic-coglycolic acid）（PLGA） nanoparticles （NPs）, encapsulating both near infrared （NIR） fluorophores and perfluorocarbons （PfCs）, were targeted to necrotic ceils. We used cyanine dyes such as IRDye 800CW, for which we have previously demonstrated specific targeting to intracellular proteins of cells that have lost membrane integrity. Here, we show specific in vivo detection of necrosis by optical imaging and fluorine magnetic resonance imaging （^19f MRI） using newly designed PLGA NP（NIR700 ＋ PfC）-PEG-800CW. Quantitative ex vivo optical imaging and ^19f MR spectroscopy of NIR-PfC content in injured brain regions and in major organs were well correlated. Both modalities allowed the in vivo identification of necrotic brain lesions in a mouse model of TBI, with optical imaging being more sensitive than ^19f MRI. Our results confirm increased blood pool residence time of PLGA NPs coated with a PEG layer and the successful targeting of TBI-damaged tissue. A single PLGA NP containing NIR-PfC enables both rapid qualitative optical monitoring of the TBI state and quantitative 3D information from deeper tissues on the extent of the lesion by MRI. These necrosis-targeting PLGA NPs can potentially be used for clinical diagnosis of brain injuries.

关键词： imaging nanoparticles contrast agents magnetic resonance imaging brain injury stroke

Local Embeddings of Some families of Subgroups of finite Groups

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Acta Mathematica Sinica,English Series 2009年第6期25卷 869-882页

作者： A.BALLESTER-BOLINCHES luis M.EZQUERRO Alexander N.SKIBA Departament d'lgebra Universitat de València Departamento Department of Mathematics Gomel State University F.Skorina

In this paper we study the influence of the partial cover and avoidance property on the subgroups of some relevant families of subgroups in a finite group.

关键词： finite group cover-avoidance property p-supersoluble groups saturated formation

Petrography and geochemistry of exported Colombian coals:Implications from correlation and regression analyses

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Energy Geoscience 2021年第3期2卷 201-210页

作者： Segun A.Akinyemi ferney Bohorquez Nazrul Islam Binoy K.Saikia Carlos H.Sampaio Tito J.Crissien luis f.O.Silva Environmental Remediation&Geopollution Group Department of GeologyFaculty of ScienceEkiti State University Ado EkitiP.M.B.5363Ado EkitiNigeria Department of Civil and Environmental Engineering Universidad de La CostaCalle 58#55-66.080002BarranquillaAtlanticoColombia Coal and Energy Group Materials Science&Technology DivisionCSIR-North East Institute of Science&TechnologyJorhat785006India Departament D’EnginyeriaMinera Industrial I TICSerra Húnter ProfUniversitatPolitecnica de Catalunya Barcelona TechAv.Bases de Manresa 61e63Manresa08242BarcelonaSpain

The petrology of coal,as determined by the microscopic analysis of organic and inorganic elemental constituents of coal,provides information on its nature and *** is used worldwide in the production of thermal energy and *** the case of high-quality Colombian coals,only limited studies have been carried *** present study presents the geochemical,mineralogical,and petrological characteristics of coal samples collected from Puerto Drummond in Cienaga,Colombia,to predict their potential ***,the ultimate,proximate,petrographic,gross calorific value(GCV),ash fusion temperature,fourier transform infrared spectroscopy(fTIR),X-ray diffraction(XRD),X-ray fluorescence(XRf),and Thermogravimetric(TG)analyses were employed in this *** petrological analysis reveals that Colombian coals are naturally more abundant in vitrinite(72%)than inertinite(14e23%)*** and aluminosilicate are the main minerals present as fine particles mixed with *** XRD and fTIR analyses show that the most common and dominant minerals are quartz,while gypsum,hematite,calcite and mica occur in lesser *** oxide composition of the coal ashes consists of 51e58%SiO2 and 18e25%Al2O3 as determined by XRf *** correlation and regression analysis,the moisture content shows a reverse correlation with GCV(Regression value of R2¼0.68).This study helps researchers to comprehend the importance of Colombian coals and presents various techniques for characterisation of coals.

关键词： Coal characterisation Geochemistry Mineralogy Coal petrology Colombia

Water-soluble hollow nanocrystals from self-assembly of AIEEactive Pt(II)metallomesogens

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Nano Research 2021年第1期14卷 245-254页

作者： Cristian Cuerva Javier fernandez-Lodeiro Mercedes Cano Jose luis Capelo-Martinez Carlos Lodeiro BIOSCOPE Research Group LAQV@REQUIMTE Chemistry DepartmentNOVA School of Science and TechnologyNOVA University Lisbon2829-516 CaparicaPortugal PROTEOMASS Scientific Society Rua dos InventoresMadam ParqueCaparica Campus2829-516 CaparicaPortugal Department of Inorganic Chemistry Complutense University of MadridCiudad Universitaria28040 MadridSpain

Luminescent hollow micro-and nanocrystals have been successfully obtained taking advantage of the self-assembly behavior and the aggregation-induced emission enhancement properties of several bispyrazolate Pt(II)metallomesogens decorated with four terminal alkyl ***-in-water droplets have been used to confine the Pt(II)compounds and drive them to be self-assembled via intermolecular Pt…Pt interactions into spherical aggregates of about 200 or 50 *** of the oil phase generates highly-stable aqueous dispersions of nanocrystals that emit a bright orange light as a result of the existence of^(3)MMLCT excited *** methods and conditions have been tested for studying the effect of several parameters such as the temperature and the stirring speed in the final particle size and in the polydispersity ***,the micro-and nanocrystals are able to entrap hydrophobic drugs between the alkyl chains of the compounds,forming stable dispersions of drug-loaded capsules in *** droplet method is applied in the area of metallomesogens for the first time to synthesize self-assembled Pt(II)nanocapsules,which opens a new field of study that could allow the use of these liquid crystal materials in biomedical applications.

关键词： R(II)metallomesogens self-assembly luminescent nanomaterials droplets nanocapsules

A New Member of the Thioredoxin Reductase family from Early Oxygenic Photosynthetic Organisms

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Molecular Plant 2017年第1期10卷 212-215页

作者： Rubén M. Buey Sergio Galindo-Trigo luis López-Maury Adrián Velázquez-Campoy José luis Revuelta f. Javier florencio José M. de Pereda Peter Schürmann Bob B. Buchanan Monica Balsera Department Microbiología y Genética Universidad de Salamanca Salamanca 37007 Spain Instituto de Recursos Naturales y Agrobiología de Salamanca (IRNASA-CSIC) Salamanca 37008 Spain Instituto de Bioquímica Vegetal y fotosíntesis (CSIC-Universidad de Sevilla) Seville 41092 Spain Institute of Biocomputation and Physics of Complex Systems (BIfI) University of Zaragoza Zaragoza 50018 Spain Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca) Salamanca 37007 Spain Laboratoire de Biologie Moléculaire et Cellulaire Université de Neuchâtel Neuchâtel 2000 Switzerland Department of Plant and Microbial Biology University of California Berkeley CA 94720 USA

Dear Editor,Thioredoxins （Trxs） are key components of the redox system that regulates the activity of a spectrum of target proteins through dithiol-disulfide exchange reactions. Trxs are reduced by mem- bers of the Trx reductase （TR） family （Jacquot et al., 2009）. NADP-dependent thioredoxin reductases （NTRs）, the most com-mon type, belong to the family of dimeric pyridine nucleotide disul-fide oxidoreductase flavoproteins that use NADPH as the source of reducing equivalents.

关键词： Thioredoxin Early Organisms