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Aquatic photo-transformation and enhanced photoinduced toxicity of ionizable tetracycline antibiotics

FRONTIERS OF ENVIRONMENTAL SCIENCE & ENGINEERING 2024年第11期18卷 139页

作者： Ge, Linke Zheng, Jinshuai halsall, crispin Chen, Chang-Er Li, Xuanyan Cao, Shengkai Zhang, Peng Shaanxi Univ Sci & Technol Sch Environm Sci & Engn Xian 710021 Peoples R China Univ Lancaster Lancaster Environm Ctr Lancaster LA1 4YQ England South China Normal Univ Environm Res Inst Sch Environm Guangzhou 510006 Peoples R China

Most antibiotics contain ionizable groups that undergo acid-base dissociation giving rise to diverse dissociated forms in aquatic systems depending on the pH of the system. In sunlit surface waters, photochemical transformation plays a crucial role in determining the fate of antibiotics. This study presents a comprehensive examination of the photo-transformation degradation kinetics, pathways and photoinduced toxicity of three widely detected tetracyclines (TCs): tetracycline (TC), oxytetracycline (OTC), and chlortetracycline (CTC). Under simulated sunlight (lambda > 290 nm), their apparent photolysis followed pseudo-first-order kinetics, with rate constants significantly increasing from H2TCs0 to TCs2-. Through competition kinetic experiments and matrix calculations, it was found that the anions HTCs- or TCs2- (pH similar to 8-10) were more reactive toward hydroxyl radicals (center dot OH), while TCs2- (pH similar to 10) reacted the fastest with singlet oxygen (O-1(2)). Considering the dissociated species, the total environmental photo-transformation half-lives of TCs were determined, revealing a strong dependence on the water pH and seasonal variation in sunlight. Generally, apparent photolysis was the dominant photochemical process, followed by O-1(2) and center dot OH oxidation. Different transformation pathways for the three reactions were determined based on the key photoproducts identified using HPLC-MS/MS. Toxicity tests and ECOSAR software calculations confirmed that the intermediates produced by the center dot OH and O-1(2) photo-oxidation processes were more toxic than the parent compounds. These findings significantly enhance our understanding of the complex photochemical fate and associated risks of TCs in aqueous environments.

关键词： Tetracyclines Dissociation Photodegradation kinetics Reactive oxygen species Transformation products Risks

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Photodegradation of hydroxyfluorenes in ice and water: A comparison of kinetics, effects of water constituents, and phototransformation by-products

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Journal of Environmental Sciences 2023年第2期124卷 139-145页

作者： Linke Ge Shengkai Cao crispin halsall Junfeng Niu Dongxiao Bai Guangkai He Peng Zhang Hongrui Ma School of Environmental Science and Engineering Shaanxi University of Science&TechnologyXi’an 710021China Lancaster Environment Centre Lancaster UniversityLancaster LA14YQUK State Environmental Protection Key Laboratory of Coastal Ecosystem National Marine Environmental Monitoring CenterDalian 116023China

The photochemical behavior of organic pollutants in ice is poorly studied in comparison to aqueous *** we report a detailed comparison of ice and aqueous photodegradation of two representative OH-PAHs,2-hydroxyfluorene(2-OHFL)and 9-hydroxyfluorene(9-OHFL),which are newly recognized contaminants in the wider environment including colder ***,their photodegradation kinetics were clearly influenced by whether they reside in ice or *** the same simulated solar irradiation(λ>290 nm),OHFLs photodegraded faster in ice than in equivalent aqueous solutions and this was attributed to the specific concentration effect caused by ***,the presence of dissolved constituents in ice also influenced photodegradation with 2-OHFL phototransforming the fastest in‘seawater’ice(k=(11.4±1.0)×10^(−2) min^(−1))followed by‘pure-water’ice((8.7±0.4)×10^(−2) min^(−1))and‘freshwater’ice((8.0±0.7)×10^(−2) min^(−1)).The presence of dissolved constituents(specifically Cl^(−),NO_(3)^(−),Fe(Ⅲ)and humic acid)influences the phototransformation kinetics,either enhancing or suppressing phototransformation,but this is based on the quantity of the constituent present in the matrixes,the specific OHFL isomer and the matrix type(e.g.,ice or aqueous solution).Careful derivation of key photointermediates was undertaken in both ice and water samples using tandem mass *** phototransformation exhibited fewer by-products and‘simpler’pathways giving rise to a range of hydroxylated fluorenes and hydroxylated fluorenones in *** results are of importance when considering the fate of PAHs and OH-PAHs in cold regions and their persistence in sunlit ice.

关键词： Ice photochemistry Hydroxyfluorene Photodegradation Kinetics Water constituents Intermediates

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Levels and trends of poly-and perfluoroalkyl substances in the Arctic environment-An update

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Emerging Contaminants 2019年第1期5卷 240-271页

作者： Derek Muir Rossana Bossi Pernilla Carlsson Marlene Evans Amila De Silva crispin halsall Cassandra Rauert Dorte Herzke Hayley Hung Robert Letcher Frank Riget Anna Roos Aquatic Contaminants Research Division Environment and Climate Change CanadaBurlingtonONCanada Department of Environmental Science Aarhus UniversityRoskildeDenmark Norwegian Institute for Water Research Fram CentreTromsøNorway Water Hydrology Ecology Division Environment and Climate Change CanadaSaskatoonSKCanada Lancaster Environment Centre Lancaster UniversityLancasterUnited Kingdom Air Quality Processes Research Section Environment and Climate Change CanadaTorontoONCanada Norwegian Institute for Air Research Fram CentreTromsøNorway Ecotoxicology and Wildlife Health Division Environment and Climate Change CanadaNational Wildlife Research CentreCarleton UniversityOttawaONCanada Department of Bioscience Aarhus UniversityRoskildeDenmark Greenland Institute of Natural Resources NuukGreenland Swedish Museum of Natural History StockholmSweden

Poly-and perfluoroalkyl substances(PFASs)are important environmental contaminants globally and in the early 2000s they were shown to be ubiquitous contaminants in Arctic *** reviews by Butt et *** Letcher et *** covered studies on levels and trends of PFASs in the Arctic that were available to *** purpose of this review is to focus on more recent work,generally published between 2009 and 2018,with emphasis on PFASs of emerging concern such as perfluoroalkyl carboxylates(PFCAs)and short-chain perfluoroalkyl sulfonates(PFSAs)and their *** measurements over the period 2006e2014 have shown that fluorotelomer alcohols(FTOHs)as well as perfluorobutanoic acid(PFBA)and perfluoroctanoic acid(PFOA)are the most prominent PFASs in the arctic atmosphere,all with increasing concentrations at Alert although PFOA concentrations declined at the Zeppelin Station(Svalbard).Results from ice cores show generally increasing deposition of PFCAs on the Devon Ice cap in the Canadian arctic while declining fluxes were found in a glacier on *** extensive dataset exists for long-term trends of long-chain PFCAs that have been reported in Arctic biota with some datasets including archived samples from the 1970s and *** in PFCAs over time vary among the same species across the North American Arctic,East and West Greenland,and *** long term time series show a decline from higher concentrations in the early *** there have been recent(post 2010)increasing trends of PFCAs in ringed seals in the Canadian Arctic,East Greenland polar bears and in arctic foxes in *** biological sampling is helping to determine these relatively short term *** levels of some PFCAs have been explained by continued emissions of long-chain PFCAs and/or their precursors and inflows to the Arctic Ocean,especially from the North *** the effectiveness of biological sampling for temporal trends in long-chain PFCAs an

关键词： Perfluoroalkyl substances PFASs Perfluoroalkyl carboxylates Perfluoroalkyl sulfonates Perfluorobutanoic acid Perfluorooctanoic acid Air Seawater Ice caps Biota Contaminants Long-range transport Review

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Ionic thermoelectric materials and devices

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Journal of Energy Chemistry 2021年第10期30卷 88-103,I0003页

作者： Dan Zhao Alois Würger Xavier crispin Laboratory of Organic Electronics Linkoping UniversityNorrkoping 60247Sweden Univ.Bordeaux&CNRS LOMA(UMR 5798)F-33405 TalenceFrance Wallenberg Wood Science Center ITNLinköping UniversityNorrköpingSweden

The tremendous amount of wasted heat from solar radiation and industry dissipation has motivated the development of thermoelectric concepts that directly convert heat into *** main challenge in practical applications for thermoelectrics is the high cost from both materials and ***,breakthrough progresses in ionic thermoelectrics open up new possibilities to charge energy storage devices when submitted to a temperature *** charging voltage is internally from the ionic Seebeck effect of the electrolyte between two *** electrolytes with high thermoelectric figure of merit are classified as ionic thermoelectric *** ionic thermoelectric materials are composed of abundant elements,and they can generate hundreds of times larger thermal voltage than that of electronic *** emerging thermoelectric category brings new hope to fabricate low cost and large area heat-to-energy conversion devices,and triggers a renewed interest for ionic *** this review,we summarize the state of the art in the new field of ionic thermoelectrics,from the driving force of the ionic thermodiffusion to material and application *** present a general map of ionic thermoelectric materials,discuss the unique characters of each type of the reported electrolytes,and propose potential optimization and future topics of ionic thermoelectrics.

关键词： Electrolytes Soret effect Thermodiffusion Thermal energy conversion

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Hall measurements reveal band-like transport in high-mobility solution-processed organic semiconductor films

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National Science Review 2024年第8期11卷 53-54页

作者： Reverant crispin Igor Zozoulenko Laboratory of Organic Electronics Department of Science and Technology Link?ping University

Organic semiconductors, composed of conjugated molecules or polymers,can be designed with specific chemical compositions, crystalline structures,nano-morphologies and electronic properties using extensive chemical synthesis tools. High charge-carrier mobility,which is crucial for device performance in transistors, organic light emitting diodes(OLEDs) and solar cells, is influenced by the overlap between the π-orbitals of adjacent molecules.

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Current research on pharmacologic and regenerative therapies for osteoarthritis

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Bone Research 2015年第4期3卷 185-198页

作者： Wei Zhang Hongwei Ouyang crispin R Dass Jiake Xu Center for Stem Cell and Tissue Engineering School of MedicineZhejiang University School of Pathology and Laboratory Medicine The University of Western Australia School of Pharmacy Building 306Curtin UniversityBentley

Osteoarthritis（OA）is a degenerative joint disorder commonly encountered in clinical practice,and is the leading cause of disability in elderly *** to the poor self-healing capacity of articular cartilage and lack of specific diagnostic biomarkers,OA is a challenging disease with limited treatment *** pharmacologic therapies such as acetaminophen,non-steroidal anti-inflammatory drugs,and opioids are effective in relieving pain but are incapable of reversing cartilage damage and are frequently associated with adverse *** research focuses on the development of new OA drugs（such as sprifermin/recombinant human fibroblast growth factor-18,tanezumab/monoclonal antibody againstβ-nerve growth factor）,which aims for more effectiveness and less incidence of adverse effects than the traditional ***,regenerative therapies（such as autologous chondrocyte implantation（ACI）,new generation of matrix-induced ACI,cell-free scaffolds,induced pluripotent stem cells（iPS cells or iPSCs）,and endogenous cell homing）are also emerging as promising alternatives as they have potential to enhance cartilage repair,and ultimately restore healthy ***,despite currently available therapies and research advances,there remain unmet medical needs in the treatment of *** review highlights current research progress on pharmacologic and regenerative therapies for OA including key advances and potential limitations.

关键词： cartilage regenerative articular challenging pluripotent disability restore repair degenerative advances

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Resection of giant gastric GIST with a new generation ultrasonic scalpel device

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World Journal of Clinical Cases 2014年第1期2卷 9-11页

作者： crispin Schneider David F Hewin Division of Surgery and Interventional Science University College London Bloomsbury Campus London WC1E 6AU United Kingdom Department of General Surgery Gloucestershire Royal Hospital Gloucester GL1 3NN United Kingdom

Gastrointestinal stroma tumours(GIST) are the most common mesenchymal tumour in the digestive tract and commonly found in the stomach. The patient described in this report presented with collapse and a palpable abdominal mass. He was found to have a large gastric GIST that penetrated through the mesocolon. Resection of the GIST was technically challenging but facilitated by a new generation ultrasonic scalpel device. In resection of gastric cancer the use of ultrasonic scalpels has been shown to reduce operating time, blood loss and length of stay. We feel that in technically challenging cases of gastric GIST the use of an ultrasonic scalpel device may be justified as well.

关键词： Gastrointestinal stroma tumours Ultrasonic scalpel Harmonic Giant tumour Stomach

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Stability of freeze-dried pH-responsive dextrin nanogels containing doxorubicin

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Asian Journal of Pharmaceutical Sciences 2016年第5期11卷 648-654页

作者： Somkamol Manchun crispin R.Dass Pornsak Sriamornsak Department of Pharmaceutical Technology Faculty of PharmacySilpakorn UniversityNakhon Pathom 73000Thailand Pharmaceutical Biopolymer Group(PBiG) Faculty of PharmacySilpakorn UniversityNakhon Pathom 73000Thailand School of Pharmacy Faculty of Health SciencesCurtin UniversityPerth 6845Australia Curtin Health Innovation Research Institute of Ageing and Chronic Disease Bentley 6102Australia

Induction of non-specific toxicities by doxorubicin(DOX) has restricted conventional DOXbased chemotherapy. p H-responsive dextrin nanogels(DNGs) have been fabricated in order to incorporate and deliver DOX to specific(targeted) sites. However, adequate stability studies of DOX-loaded DNGs are required for selection of storage conditions. The aim of this study was therefore to evaluate the accelerated(25 °C/60% RH) and long-term(5 °C) stability of DNGs prepared with formaldehyde(FDNGs) and glyoxal(GDNGs) as cross-linker by determining the change in their physicochemical properties. The mean diameter decreased with time during long-term storage. The drug content between freshly prepared(initial day) and after storage at 5 °C for 180 days of DOX-loaded FDNGs and DOX-loaded GDNGs was not significantly different(p > 0.05), but decreased after storage under the accelerated condition. The release of DOX from all DNGs was pH-dependent. However, DNGs kept under the accelerated condition showed higher amount of DOX release than those stored at 5 °C and the freshly prepared ones. The results indicate that the stability of DNGs could be improved by their storage at 5 °C.

关键词： Stability Nanogels Dextrin

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Far-infrared absorption studies of Be acceptors in δ-doped GaAs/AlAs multiple quantum wells

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Science China(Physics,Mechanics & Astronomy) 2006年第6期49卷 702-708页

作者： M. P. halsall P. Harrison M. J. Steer School of Physics and Astronomy the University of ManchesterManchester M60 1QD U. K. School of Electronic and Electrical Engineering University of LeedsLS2 9JT U. K. EPSRC Ⅲ-V Semiconductor Central Facility Department of Electronic and Electrical Engineering University of SheffieldS1 3JD U. K.

We report a far-infrared absorption study of internal transitions of shallow Be acceptors in both bulk GaAs and a series of δ-doped GaAs/AlAs multiple quantum well samples with well thicknesses of 20,15 and 10 nm. Low temperature far-infrared absorp-tion measurements clearly show three principal absorption lines due to transitions of Be-acceptor states from the ground state to the first three odd-parity excited states,respec-tively. Using a variational principle,the 2p-1s transition energies of quantum confined Be acceptors are calculated as a function of the well width. It is found that the theoretical calculation of the 2pz → 1s transitions is in good agreement with the D-like line experi-mental data.

关键词： shallow acceptor impurities,δ-doped,GaAs/AlAs multiple quantum wells,far-infrared absorptions.

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The past,present,and future of piezoelectric fluoropolymers:Towards efficient and robust wearable nanogenerators

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Nano Research Energy 2023年第4期2卷 41-77页

作者： Md.Mehebub Aam Xavier crispin Laboratory of Organic Electronics Department of Science and TechnologyLinköping UniversityNorrköping SE-60174Sweden

Polyvinylidene difluoride(PVDF)derivatives in metal/PVDF/metal(MPM)sandwich structures have been studied extensively since *** copolymers of the same family have been discovered with fascinating piezoelectric,pyroelectric,electrocaloric,and ferroelectric *** processing,flexibility,lightweight,and thermal stability make this class of materials complementary to ***,PVDF based polymers potentially compete with inorganic materials for a broad range of technologies such as energy generators,loudspeakers,coolers,and ***,the stable non-electroactiveα-phase and hydrophobic nature of PVDF are the main barriers for developoing high performing and robust MPM devices in electronic *** this review,we present an up-to-date overview on different methods to induce the electroactiveβ-phase and improve the adhesion strength with metals to ensure robust and durable MPM *** go through advantages and disadvantages of several methods and pinpoint future opportunities in this research area.A special attention is paid to wearable piezoelectric nanogenerators for energy harvesting from human body motion,where flexible PVDF derivatives are compared with rigid piezoelectric *** the piezoelectric coefficient of PVDF(d_(33)~24–34 pm/V)is one order lower than ceramic materials,novel co-polymers of PVDF display d_(33)>1000 pm/V upon *** shows promise to bring piezoelectrics to flexible and large-area applications such as smart *** also discussed challenges to improve wearability,such as light weight,breathability,and flexibility.

关键词： polyvinylidene difluoride(PVDF) nanogenerators energy harvesting piezoelectric polymer surface modification metal-PVDF adhesion wearable generators

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