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Hybrid Ni_(2)P/coP Nanosheets as Efficient and Robust Electrocatalysts for Domestic Wastewater Splitting

Energy & Environmental Materials 2023年第5期6卷 330-339页

作者： Yeshu Tan Jianrui Feng Liqun Kang Longxiang Liu Fangjia Zhao Siyu Zhao Dan J.L.Brett Paul R.Shearing Guanjie He ivan P.Parkin christopher Ingold Laboratory Department of ChemistryUniversity College LondonLondon WC1H 0AJUK Materials and catalysis Laboratory Department of Chemical EngineeringUniversity College LondonLondon WC1E 7JEUK Electrochemical Innovation Laboratory Department of Chemical EngineeringUniversity College LondonLondon WC1E 7JEUK School of chemistry University of LincolnJoseph Banks LaboratoriesLincolnLN67DLUK

The development of low-cost,robust and efficient non-noble metal electrocatalysts is still a pursuit for the hydrogen evolution reaction(HER).Herein,a self-standing electrocatalyst,Ni_(2)P/coP nanosheet,was fabricated directly on three-dimensional Ni foams by two facile steps,which illustrated both high activity and stability for HER in different *** from the porous structures of nanosheets with large specific surface area and the hybrid Ni_(2)P/coP,the as-prepared electrocatalyst presented remarkable HER with overpotentials of 65.2 and 87.8 mV to reach a current density of-10 mA cm^(-2)in neutral and alkaline media,*** function theory calculations revealed a lower activation energy of water dissociation and efficient HER steps of hybrid Ni_(2)P/coP nanosheets compared with mono *** self-standing electrocatalyst maintained excellent chemical ***,the HER process in domestic wastewater was realized with more impressive performance by using Ni_(2)P/coP nanosheets compared with commercial Pt/*** was continuously generated for 20 h in mildly alkaline dishwashing *** work provides a feasible way to fabricate non-noble metal and self-standing hybrid bimetallic phosphides for HER in neutral and alkaline media,showing great potential for efficient hydrogen production by re-utilizing wastewater resources.

关键词： hybrid hydrogen evolution reaction Ni_(2)P/coP nanosheet self-standing wastewater splitting

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Bright trions in direct-bandgap silicon nanocrystals revealed by low-temperature single-nanocrystal spectroscopy

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Light(Science & Applications) 2015年第1期4卷 179-186页

作者： Katerina Kusova ivan Pelant Jan Valenta Institute of Physics of the AScR v.v.i.Cukrovarnicka 1016200 Prague 6Czech Republic Faculty of Mathematics and Physics Charles UniversityKe Karlovu 512116 Prague 2Czech Republic

Strain-engineered silicon nanocrystals(SiNcs)have recently been shown to possess direct ***,we report the observation of a rich structure in the single-nanocrystal photoluminescence spectra of strain-engineered direct-bandgap SiNcs in the temperature range of 9–300 *** relationship between individual types of spectra is discussed,and the numerical modeling of spectral diffusion of the experimentally acquired spectra reveals a common origin for most *** intrinsic spectral shape is shown to be a structure that contains three peaks,approximately 150 meV apart,each of which possesses a Si phonon *** spectral lines,reaching ≤ meV at 20 K,are *** observed temperature dependence of the spectral structure can be assigned to the radiative recombination of positively charged trions,in contrast to several previous reports linking a very similar shape to phonons in the surface capping *** result serves as strong additional support for the direct-bandgap nature of the investigated SiNcs.

关键词： direct bandgap low-temperature single-nanocrystal spectroscopy silicon nanocrystals trions

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Quantum spin Hall effect in inverted InAs/GaSb quantum wells

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Frontiers of physics 2012年第2期7卷 200-207页

作者： ivan Knez (1) Rui-Rui Du (1) 1. Department of Physics and Astronomy Rice University Houston TX 77251-1892 USA

We review the recent experimental progress towards observing quantum spin Hall effect in inverted InAs/GaSb quantum wells （QWs）. low temperature transport measurements in the hybridization gap show bulk conductivity of a non-trivial origin, while the length and width dependence of con- ductance in this regime show strong evidence for the existence of helical edge modes proposed by Liu et al. [Phys. Rev. Lett., 2008, 100： 236601]. Surprisingly, edge modes persist in spite of compa- rable bulk conduction and show only weak dependence on magnetic field. We elucidate that seeming independence of edge on bulk transport comes due to the disparity in Fermi-wave vectors between the bulk and the edge, leading to a total internal reflection of the edge modes.

关键词： quantum spin Hall effect InAs/GaSb quantum wells topological insulators

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Neuroprotective therapy for retinal neurodegenerative diseases by stem cell secretome

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Neural Regeneration Research 2021年第1期16卷 117-118页

作者： Ricardo Usategui-Martín ivan Fernandez-Bueno Instituto Universitario de Oftalmobiología Aplicada(IOBA) Retina GroupUniversidad de ValladolidValladolidSpain centro en Red de Medicina Regenerativa y Terapia celular de castilla y León Red Temática de Investigación Cooperativa en SaludOftaredInstituto de Salud Carlos IIIValladolidSpain

Retinal neurodegenerative diseases like agerelated macular degeneration,glaucoma,diabetic retinopathy or retinitis pigmentosa are the most frequent causes of incurable low vision and blindness *** had been estimated that the prevalence of these diseases varies between 1/750 and 1/5000 depending on the region,the level of consanguinity or ethnicity(Na et al.,2017).The functional and structural complexity of the retina makes it susceptible to multiple types of pathogenic damage.

关键词： diseases protective degenerative

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Implantable cardiac defibrillators in octogenarians

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Journal of Geriatric cardiology 2023年第1期20卷 23-31页

作者： Maarten Pauwelyn Sebastian Ingelaere Ruben Hoffmann Johan Vijgen Georges H.Mairesse ivan Blankoff Yves Vandekerckhove Jean-Benoit le Polain de Waroux Bert Vandenberk Rik Willems University Hospitals Leuven CardiologyLeuvenBelgium KU Leuven Department of Cardiovascular SciencesLeuvenBelgium UZA Department of CardiologyAntwerpBelgium Jessa Ziekenhuis Department of CardiologyHasseltBelgium cliniques du Sud Luxembourg Department of CardiologyArlonBelgium cHU charleroi Department of CardiologyCharleroiBelgium AZ Sint-Jan Department of CardiologyBruggeBelgium University of calgary Libin Cardiovascular InstituteCalgaryCanada

OBJEcTIVE Implantable cardiac defibrillators(IcD)implantation in the very elderly remains *** aimed to describe the experience and outcome of patients over 80 years old implanted with an IcD in *** Data were extracted from the national QERMID-IcD *** implantations performed in octogenarians between February 2010 and March 2019 were *** on baseline patient characteristics,type of prevention,device configuration and all-cause mortality were *** determine predictors of mortality,multivariable cox proportional hazard regression modelling was *** Nationwide,704 primo IcD implantations were performed in octogenarians(median age 82,IQR 81-83 years;83% male and 45% secondary prevention).During a mean follow-up of 3.1±2.3 years,249(35%)patients died,of which 76(11%)within the first year after *** multivariable cox regression analysis age(HR=1.15,P=0.004),oncological history(HR=2.43,P=0.027)and secondary prevention(HR=2.23,P=0.001)were independently associated with 1-year mortality.A better preserved left ventricular ejection fraction(LVEF)was associated with a better outcome(HR=0.97,P=0.002).Regarding overall mortality multivariable analysis withheld age,history of atrial fibrillation,centre volume and oncological history as significant *** LVEF was again protective(HR=0.99,P=0.008).cONcLUSIONS Primary IcD implantation in octogenarians is not often performed in *** this population,11%died within the first year after IcD *** age,oncological history,secondary prevention and a lower LVEF were associated with an increased one-year ***,low LVEF,atrial fibrillation,centre volume and oncological history were indicative of higher overall mortality.

关键词： prevention implantation protective

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Homing and migration of mesenchymal stromal cells: How to improve the efficacy of cell therapy?

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World Journal of Stem cells 2016年第3期8卷 73-87页

作者： Ann De Becker ivan Van Riet Department clinical HematologyStem cell Laboratory Universitair Ziekenhuis Brussel Vrije Universiteit Brussel (VUB)

Mesenchymal stromal cells(MScs) are currently being investigated for use in a wide variety of clinical applications. For most of these applications, systemic delivery of the cells is preferred. However, this requires the homing and migration of MScs to a target tissue. Although MSc hominghas been described, this process does not appear to be highly efficacious because only a few cells reach the target tissue and remain there after systemic administration. This has been ascribed to low expression levels of homing molecules, the loss of expression of such molecules during expansion, and the heterogeneity of MScs in cultures and MSc culture protocols. To overcome these limitations, different methods to improve the homing capacity of MScs have been examined. Here, we review the current understanding of MSc homing, with a particular focus on homing to bone marrow. In addition, we summarize the strategies that have been developed to improve this process. A better understanding of MSc biology, MSc migration and homing mechanisms will allow us to prepare MScs with optimal homing capacities. The efficacy of therapeutic applications is dependent on efficient delivery of the cells and can, therefore, only benefit from better insights into the homing mechanisms.

关键词： Mesenchymal stromal cells Homing Bone marrow Homing receptors Extravasation

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Anomalies of bromine in the estuarine sediments as a signal of floods associated with typhoons

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chinese Journal of Oceanology and Limnology 2015年第6期33卷 1489-1495页

作者： ivan KALUGIN Anatolii ASTAKHOV Andrey DARIN Kirill AKSENTOV Sobolev Institute of Geology and Mineralogy Siberian Branch Russian Academy of Science V.I.Il’ichev Pacific Oceanological Institute Far Eastern Branch Russian Academy of Science

X-ray fluorescence scanning with synchrotron radiation was performed to study sediment core records of floods in Amur Bay,Sea of *** of 3–8 mm with abnormally low bromine content were formed by the Razdolnaya River discharge to the central part of the bay during extreme floods,accompanied by severe storms at *** conditions in the region are typical for periods of deep tropical cyclones(typhoons),to which the distinguished interlayers were compared on the *** approach was made possible thanks to the high rate of sedimentation in the bay(3–5 mm/a) and low bioturbation of sediments under anoxic conditions.

关键词：河口沉积物溴含量洪水台风异常信号水沉积物同步辐射

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Predator-induced physiological responses in tadpoles challenged with herbicide pollution

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current Zoology 2013年第4期59卷 475-484页

作者： Pablo BURRAcO Lidia Jimenez DUARTE ivan GOMEZ-MESTRE Ecology Evolution and Development Group Estaci6n Biol6gica de Dofiana (EBD-CSIC) E-41092 Seville Spain Av. Las ciencias 4 2℃ 41020 Sevilla Spain

Predators induce plastic responses in multiple prey taxa, ranging from morphological to behavioral or physiological changes. In amphibians, tadpoles activate plastic responses to reduce predation risk by reducing their activity rate and altering their morphology, specifically tail depth and pigmentation. Furthermore, there is now evidence that tadpoles’ defenses are modified when predators combine with other stressful factors such as pollutants or competitors, but our knowledge on the physiological responses underlying these responses is still scarce. Here we study physiological responses inPelobates cultripestadpoles exposed to a natural predator (larvae of the aquatic beetleDytiscus circumflexus), non-lethal concentrations of herbicide (gly-phosate, 0.5 mg/L and 1.0 mg/L) or both factors combined. We measured corticosterone levels, standard metabolic rate, oxidative damage (TBARS) and activity of antioxidant enzymes, and immune response (via leukocyte count). Tadpoles reduced their corticosterone concentration by ca. 24% in the presence of predator cues, whereas corticosterone did not change in the presence of glyphosate. Two enzymes involved in antioxidant response also decreased in the presence of predators (14.7% and 13.2% respectively) but not to glyphosate. Herbicide, however, increased the number of neutrophils and reduced that of lymphocytes, and had an interaction effect with predator presence. Standard metabolic rate did not vary across treatments in our experiment. Thus we show a marked physiological response to the presence of predators but little evidence for interaction between predators and low levels of herbicide. Multiple assessment of the physiological state of animals is important to understand the basis and consequences of phenotypic plasticity.

关键词：生理反应捕食者除草剂污染物蝌蚪抗氧化酶活性标准代谢率两栖动物

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Beaconless Position-based Routing with Guaranteed Delivery for Wireless Ad hoc and Sensor Networks

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自动化学报 2006年第6期32卷 846-855页

作者： cHAWLA Mohit GOEL Nishith KALAIcHELVAN Kalai NAYAK Amiya STOJMENOVIc ivan Department of computer Science & Engineering IIT GuwahatiGuwahati 781039India cistel Technology Inc OttawaOntario K2E 7V7Canada EION Technology Inc OttawaOntario K1Y 2X5Canada SITE University of OttawaOttawaOntario K1N 6N5Canada

Existing position-based routing algorithms, where packets are forwarded in the geographic direction of the destination, normally require that the forwarding node should know the positions of all neighbors in its transmission range. This information on direct neighbors is gained by observing beacon messages that each node sends out periodically. Several beaconless greedy routing schemes have been proposed recently. However, none of the existing beaconless schemes guarantee the delivery of packets. Moreover, they incur communication overhead by sending excessive control messages or by broadcasting data packets. In this paper, we describe how existing localized position based routing schemes that guarantee delivery can be made beaconless, while preserving the same routes. In our guaranteed delivery beaconless routing scheme, the next hop is selected through the use of control RTS/cTS messages and biased timeouts. In greedy mode, the neighbor closest to destination responds first. In recovery mode, nodes closer to the source will select shorter timeouts, so that other neighbors, overhearing cTS packets, can eliminate their own cTS packets if they realize that their link to the source is not part of Gabriel graph. Nodes also cancel their packets after receiving data message sent by source to the selected neighbor. We analyze the behavior of our scheme on our simulation environment assuming ideal MAc, following GOAFR+ and GFG routing schemes. Our results demonstrate low communication overhead in addition to guaranteed delivery.

关键词： Beaconless routing geometric routing guaranteed delivery sensor networks

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Wearable devices and IoT applications for symptom detection, infection tracking, and diffusion containment of the cOVID-19 pandemic: a survey

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Frontiers of Information Technology & Electronic Engineering 2021年第11期22卷 1413-1442页

作者： Roberto DEFAZIO Nicola ivan GIANNOccARO Miguel cARRAScO Ramiro VELAZQUEZ Paolo VIScONTI Department of Innovation Engineering University of SalentoLecce73100Italy Facultad de Ingeniería y ciencias Universidad Adolfo IbáñezPeñalolénSantiago7941169Chile Facultad de Ingeniería Universidad PanamericanaAguascalientes20290Mexico

Until a safe and effective vaccine to fight the SARS-coV-2 virus is developed and available for the global population, preventive measures, such as wearable tracking and monitoring systems supported by Internet of Things(IoT) infrastructures, are valuable tools for containing the pandemic. In this review paper we analyze innovative wearable systems for limiting the virus spread, early detection of the first symptoms of the coronavirus disease cOVID-19 infection, and remote monitoring of the health conditions of infected patients during the quarantine. The attention is focused on systems allowing quick user screening through ready-to-use hardware and software components. Such sensor-based systems monitor the principal vital signs, detect symptoms related to cOVID-19 early, and alert patients and medical staff. Novel wearable devices for complying with social distancing rules and limiting interpersonal contagion(such as smart masks) are investigated and analyzed. In addition, an overview of implantable devices for monitoring the effects of cOVID-19 on the cardiovascular system is presented. Then we report an overview of tracing strategies and technologies for containing the cOVID-19 pandemic based on IoT technologies, wearable devices, and cloud computing. In detail, we demonstrate the potential of radio frequency based signal technology, including Bluetooth low Energy(BLE), Wi-Fi, and radio frequency identification(RFID), often combined with Apps and cloud technology. Finally, critical analysis and comparisons of the different discussed solutions are presented, highlighting their potential and providing new insights for developing innovative tools for facing future pandemics.

关键词： Wearable devices IoT health-monitoring applications Medical sensors cOVID-19 pandemic Symptom detection

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