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  • Article
    Priebe A, Goret G, Bleuet P, Audoit G, Laurencin J, Barnes JP.
    J Microsc. 2016 11;264(2):247-251.
    This paper shows how X-ray computed nanotomography (CNT) can be correlated with focused ion beam time-of-flight secondary ion mass spectrometry (FIB-TOF-SIMS) tomography on the same sample to investigate both the morphological and elemental structure. This methodology is applicable to relatively large specimens with dimensions of several tens of microns whilst maintaining a high spatial resolution of the order of 100 nm. However, combining X-ray CNT and FIB-TOF-SIMS tomography requires innovative sample preparation protocols to allow both experiments to be conducted on exactly the same sample without chemically or structurally modifying the sample between measurements. Moreover, dedicated algorithms have been developed for effective data fusion that is biased with nine degrees of freedom. This methodology has been tested using a porous and heterogeneous solid oxide fuel cell (SOFC) that has features varying in size by three orders of magnitude - from hundreds of nanometre large pores and grains to tens of micron wide functional layers.
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  • Article
    Wang X, Zhu T, Chang S, Lu Y, Mi W, Wang W.
    ACS Appl Mater Interfaces. 2020 Mar 04;12(9):11252-11264.
    As a promising microwave absorber filler, molybdenum disulfide (MoS2), because of the unique structure, high electrical conductivity, and polarization effect, is receiving more and more interest. Developing MoS2-based composites with specific structure and morphology is a hot top in the field of microwave absorbers, because of its strong multiple scattering and reflecting for microwaves as well as its unique interfacial characteristics. Now, with a facile solvothermal method, a novel core-shell CoFe2O4@1T/2H-MoS2 composite is synthesized, where the CoFe2O4 nanospheres are entirely embedded in a special three-dimensional (3D) nest-like 1T/2H phase MoS2. Notably, in comparison with superparamagnetic CoFe2O4 nanospheres, the coercivities of as-synthesized CoFe2O4@1T/2H-MoS2 composites greatly increase. Here, 1T/2H-MoS2 exhibits ferromagnetism superimposed onto large diamagnetism. It is noted that, by adjusting the content of 1T/2H-phase MoS2, the microwave absorption performance of as-synthesized composites can be effectively tuned. The combination of 1T/2H-MoS2 with CoFe2O4 helps to adjust the permittivity and optimize the impedance matching of the composites. Impressively, a minimum reflection loss (RLmin) of -68.5 dB for the as-synthesized composites with a thickness of 1.81 mm is gained at 13.2 GHz; meanwhile, a broad effective bandwidth of 4.56 GHz ranged from 13.2 to 17.76 GHz is achieved at 1.6 mm. Further, the overall effective bandwidth (RL < -10 dB) is obtained up to 14.5 GHz from 3.5 to 18.0 GHz, covering more than 90% of the measured frequency range. The high microwave absorption performance is ascribed to the special structure design with the core of magnetic CoFe2O4 nanospheres and the shell of dielectric nest-like 1T/2H-MoS2 as well as their appropriate impedance matching. From the perspective of basic research and practical microwave application, this study provides another feasible and effective pathway to design novel MoS2-based magnetic/dielectric microwave absorbers.
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  • Article
    Yin XH, Yang C, Li XP, Liang D, Zhang ZH, Tang Y, He LJ.
    Opt Express. 2018 Apr 30;26(9):11250-11264.
    This work presents a novel nondestructive cavity pressure characterization approach in microinjection molding (μIM) through measuring 3D part thickness distributions. For this purpose, a plano lens was designed and experiments based on Taguchi method were conducted. Both overall and local lens thickness distributions under various process conditions were analyzed in terms of their relevance with the cavity pressure during molding. Unexpectedly, a reliable linear regression model was developed fulfilling nondestructive multi-point or even continuous cavity pressure characterization with the overall lens thickness distribution. Furthermore, the topography of the constructed 3D thickness surface was found to depend on both process condition and measuring position. Finally, the process conditions were optimized for obtaining uniform distributions of both 3D thickness and cavity pressure.
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  • Article
    Goldberg GR, Solis G, John JT, Olvet DM, Kranz KA.
    MedEdPORTAL. 2022;18:11264.
    Introduction: Given the growing population of older adults, it is of utmost importance for all future physicians to be trained in the core skills of conducting geriatric assessment.
    Methods: We designed an interactive, skills-based session introducing core competencies for geriatric assessment for second-year medical students (MS2s). We organized our curriculum for early learners based on the 4Ms framework: mind/memory, medications, mobility, and matters most. The session consisted of brief didactics with integration of real-time skills-based practice. Students completed pre- and postsession surveys to assess their confidence in their knowledge and skills. All students completed a geriatric assessment during a clinical skills encounter as part of a multistation, end-of-course, summative clinical skills examination (CSE). The session was conducted virtually over 2 academic years, and the CSE was conducted virtually in 2020 and in person in 2021.
    Results: One hundred ninety-nine MS2s participated in the session (100 in 2020, 99 in 2021). All students surveyed (33%) reported improved confidence in geriatric knowledge and skills by the end of the session (ps < .001). Students were more likely to use a cognitive screening tool, ask about advance care planning, and assess medication adherence on the CSE in 2021 compared to 2020 (ps < .001).
    Discussion: We provide an interactive curriculum for MS2s to develop geriatric assessment skills. The curriculum and assessment tools are versatile, can be easily integrated into any medical school curriculum, and can be effectively delivered in person or on a virtual platform.
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  • Article
    Chuard N, Fujisawa K, Morelli P, Saarbach J, Winssinger N, Metrangolo P, Resnati G, Sakai N, Matile S.
    J Am Chem Soc. 2016 09 07;138(35):11264-71.
    In this report, we elaborate on two new concepts to activate arginine-rich cell-penetrating peptides (CPPs). Early on, we have argued that repulsion-driven ion-pairing interactions with anionic lipids account for their ability to move across hydrophobic cell membranes and that hydrophobic anions such as pyrenebutyrate can accelerate this process to kinetically outcompete endosomal capture. The original explanation that the high activity of pyrenebutyrate might originate from ionpair-π interactions between CPP and activator implied that replacement of the π-basic pyrene with polarized push-pull aromatics should afford more powerful CPP activators. To elaborate on this hypothesis, we prepared a small collection of anionic amphiphiles that could recognize cations by ionpair-π interactions. Consistent with theoretical predictions, we find that parallel but not antiparallel ionpair-π interactions afford operational CPP activators in model membranes and cells. The alternative suggestion that the high activity of pyrenebutyrate might originate from self-assembly in membranes was explored with perfluorinated fatty acids. Their fluorophilicity was expected to promote self-assembly in membranes, while their high acidity should prevent charge neutralization in response to self-assembly, i.e., generate repulsion-driven ion-pairing interactions. Consistent with these expectations, we find that perfluorinated fatty acids are powerful CPP activators in HeLa cells but not in model membranes. These findings support parallel ionpair-π interactions and repulsion-driven ion pairing with self-assembled fluorophiles as innovative concepts to activate CPPs. These results also add much corroborative support for counterion-mediated uptake as the productive mode of action of arginine-rich CPPs.
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  • Article
    Balboni PG, Minia A, Grossi MP, Barbanti-Brodano G, Mattioli A, Fiume L.
    Nature. 1976 Nov 11;264(5582):181-3.
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  • Article
    Rollin M, Coulaud R, Danger M, Sohm B, Flayac J, Bec A, Chaumot A, Geffard O, Felten V.
    Environ Sci Pollut Res Int. 2018 Apr;25(12):11264-11280.
    Gammarus fossarum is an often-abundant crustacean detritivore that contributes importantly to leaf litter breakdown in oligotrophic, mainly heterotrophic, headwater streams. This species requires large amounts of Ca to moult, thus allowing growth and reproduction. Because resource quality is tightly coupled to the organism's growth and physiological status, we hypothesised that low Ca concentration [Ca] and low food resource quality (low phosphorus [P] and/or reduced highly unsaturated fatty acid [HUFA] contents) would interactively impair molecular responses (gene expression) and reproduction of G. fossarum. To investigate the effects of food resources quality, we experimentally manipulated the P content of sycamore leaves and also used diatoms because they contain high amounts of HUFAs. Three resource quality treatments were tested: low quality (LQ, unmanipulated leaves: low P content), high quality 1 (HQ1; P-manipulated leaves: high P content), and high quality 2 (unmanipulated leaves supplemented with a pellet containing diatoms: high P and HUFA content). Naturally, demineralised stream water was supplemented with CaSO4 to obtain three Ca concentrations (2, 3.5, and 10.5 mg Ca L-1). For 21 days, pairs of G. fossarum were individually exposed to one of the nine treatments (3 [Ca] × 3 resource qualities). At the individual level, strong and significant delays in moult stage were observed in gammarids exposed to lower [Ca] and to lower resource quality, with additive effects lengthening the duration of the reproductive cycle. Effects at the molecular level were investigated by measuring expression of 12 genes involved in energy production, translation, or Ca or P homeostasis. Expression of ATP synthase beta (higher in HQ2), calcified cuticle protein (higher in HQ1 and HQ2), and tropomyosin (higher in HQ2 compared to HQ1) was significantly affected by resource quality, and significant additive effects on Ca transporting ATPase expression were induced by [Ca] and resource quality (higher for low [Ca] and higher resource quality). These results highlight the potential drastic deleterious effects of water [Ca] depletion on G. fossarum physiology, populations, and ecosystem functioning, especially in oligotrophic environments.
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  • Article
    Hanly P, Ortega Ortega M, Pearce A, Soerjomataram I, Sharp L.
    Soc Sci Med. 2020 11;264:113289.
    The friction cost approach (FCA) estimates the productivity costs of disease from an employer's perspective but the lack of estimates of friction periods in different countries limits its use. Our aim was to use labour market aggregates to generate two alternative estimates of the friction period for European countries and to apply the FCA to illustrate the impact on cancer-related lost productivity costs. We included thirty countries (EU 27 + the United Kingdom, Switzerland and Norway). Base-case Method 1BC used annual Dutch vacancy stock and flow data (2001-2019) to estimate friction periods for this country. A regression model was employed using Dutch data and country-specific vacancy and unemployment rates to generate country-specific friction period estimates for the other 29 countries. Alternative Method 2ALT used country-specific newly occupied jobs as a proxy vacancy flow variable and vacancy stock data to generate friction period estimates. These were applied, within the FCA, to premature cancer mortality data (from GLOBOCAN2018) for all cancers combined for Western European countries. Costs are in €2018. Method 1BC estimated friction periods in 2018 ranged from 70.8 days for Greece to 145.9 days for the Czech Republic, with a mean duration of 95.3 days. Method 2ALT produced a mean friction period of 80.0 days. On average, across countries, Method 2ALT friction periods were 15.4 days (-18.5%) shorter than Method 1BC estimates. Friction period estimates over the last decade were shorter than those for 2018 reflecting lower vacancy rates. Total cancer premature mortality costs according to FCA Method 1BC amounted to €1.0 billion in 2018 for Western Europe compared to €0.99 billion for Method 2ALT. We developed two alternative - and viable - methods to estimate country-specific friction periods. These approaches will enable researchers to apply the FCA to estimate the productivity cost of diseases across Europe from an employer's perspective.
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  • Article
    Berisha A, Combellas C, Kanoufi F, Médard J, Decorse P, Mangeney C, Kherbouche I, Seydou M, Maurel F, Pinson J.
    Langmuir. 2018 09 25;34(38):11264-11271.
    The surface of gold can be modified with alkyl groups through a radical crossover reaction involving alkyliodides or bromides in the presence of a sterically hindered diazonium salt. In this paper, we characterize the Au-C(alkyl) bond by surface-enhanced Raman spectroscopy (SERS); the corresponding peak appears at 387 cm-1 close to the value obtained by theoretical modeling. The Au-C(alkyl) bond energy is also calculated, it reaches -36.9 kcal mol-1 similar to that of an Au-S-alkyl bond but also of an Au-C(aryl) bond. In agreement with the similar energies of Au-C(alkyl) and Au-S-(alkyl), we demonstrate experimentally that these groups can be exchanged on the surface of gold.
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  • Article
    Liu D, Cheng H, Zhu X, Wang G, Wang N.
    ACS Appl Mater Interfaces. 2013 Nov 13;5(21):11258-64.
    We developed an analog memristor based on the thickening/thinning of Ag nanofilaments in amorphous La(1-x)Sr(x)MnO3 (a-LSMO) thin films. The Ag/a-LSMO/Pt memristor exhibited excellent pinched hysteresis loops under high-excitation frequency, and the areas enclosed by the pinched hysteresis loops shrank with increasing excitation frequency, which is a characteristic typical of a memristor. The memristor also showed continuously tunable synapselike resistance and stable endurance. The a-LSMO thin films in the memristor acted as a solid electrolyte for Ag(+) cations, and only the Ag/a-LSMO/Pt memristor electroformed with a larger current compliance easily exhibited high-frequency pinched hysteresis loops. On the basis of the electrochemical metallization (ECM) theory and electrical transport models of quantum wires and nanowires, we concluded that the memristance is ultimately determined by the amount of charge supplied by the external current. The state equations of the memristor were established, and charge was the state variable. This study provides a new analog memristor based on metal nanofilaments thickening/thinning in ECM cells, which can be extended to other resistive switching materials. The new memristor may enable the development of beyond von Neumann computers.
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  • Article
    Simpson MJ, Hjelmqvist D, López-Alarcón C, Karamehmedovic N, Minehan TG, Yepremyan A, Salehani B, Lissi E, Joubert E, Udekwu KI, Alarcon EI.
    Molecules. 2013 Sep 12;18(9):11264-80.
    The anti-peroxyl radical quality of two aqueous rooibos infusions and solutions of their most abundant glycosylated polyphenols was evaluated using pyrogallol red and fluorescein-based oxygen radical absorbance ratios. It was observed that the artificial infusions, prepared using only the most abundant polyphenols present in rooibos and at concentrations similar to those found in the natural infusions, showed greater antioxidant quality than the latter infusions, reaching values close to those reported for tea infusions. Additionally, the antimicrobial activity of the natural and artificial infusions was assessed against three species of bacteria: Gram (+) Staphylococus epidermidis and Staphylococcus aureus and Gram (-) Escherichia coli. When compared to the natural infusions the artificial beverages did not demonstrate any bacterostatic/cidal activity, suggesting that the antibacterial activity of rooibos is related to compounds other than the glycosylated polyphenols employed in our study.
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  • Article
    Deleon H.
    J Microsc. 2016 11;264(2):189-197.
    Sample preparation for scanning electron microscopy (SEM) may vary by cellular type, composition and method of cultivation. It has been proposed here that a generalized method of sample preparation may be applied for the visualization of bacteria, fungi, and human cellular tissue without modification of protocol between cell types. The following protocol was developed to incorporate polystyrene disk substrates in the simplification of sample preparation for SEM and reduce the possibility of processing artefacts. The proposed method of preparation may be applied to samples grown in either liquid or solid cultural medium regardless of cell type. With the proposed protocol, centrifugation, isolation and critical point drying are not required, therefore increasing specimen integrity. The incorporation of polystyrene disks showed positive cellular adhesion and applications in SEM for bacterial, fungal and human neuronal tissue. In addition, the simplicity of the proposed protocol is highly adaptable and may be further incorporated to visually analyse the effects of antifungals, antibiotics and disease pathogenesis through pathogen-host interactions. The proposed method of specimen preparation was incorporated in either liquid or solid state growth mediums during the cultivation of the selected cellular samples and revealed great promise in the preservation and visualization under the scanning electron microscope.
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  • Article
    Chu YT, Chanda K, Lin PH, Huang MH.
    Langmuir. 2012 Jul 31;28(30):11258-64.
    In this work, palladium tripod nanocrystals have been synthesized by mixing an aqueous solution of cetyltrimethylammonium bromide (CTAB) surfactant, Na(2)PdCl(4), copper acetate, and ascorbic acid at 30 °C for 3 h. Addition of a small amount of copper ion source is critical to the formation of these tripods with a pod length reaching 100 nm. The incorporation of Cu atoms into the Pd tripods has been verified. The entire Pd tripod is single-crystalline with their branches growing along the [111] and [200] directions. Formation of side branches can be observed in some tripods. Triangular nanoplates are initially formed and evolved into the tripod structure in 20-30 min of reaction. Further growth leads to elongation of the pods. The large Pd tripods can serve as active and recyclable catalysts for a broad range of Sonogashira coupling reactions in water using a variety of aromatic halides containing electron-donating and -withdrawing substituents.
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  • Article
    Ogura A, Takahashi K.
    Nature. 1976 Nov 11;264(5582):170-2.
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  • Article
    Williams HF, Moejes K, Williams J, Almeida JR, Savania R, Senthilkumaran S, Patel K, Vaiyapuri S.
    PLoS Negl Trop Dis. 2023 04;17(4):e0011264.
    With the continued growth of human populations, rural urbanisation and habitat degradation are on the rise, resulting in the displacement of native wildlife and an increase in human-wildlife conflicts. The presence of human habitation and waste often attracts rodents and thereby, snakes, leading to increased snake sightings in homes. To address this problem, snake handlers, who are volunteers that remove and relocate snakes away from human development areas, are called upon. However, snake removal is a high-risk task that poses a risk of envenomation, particularly when dealing with spitting snakes. Several cobra species have the ability to spit venom. If the venom enters a person's eye, it can result in ophthalmic envenomation, which can have serious consequences for their eyesight. Therefore, snake handlers should take precautions, wear suitable eye protection, and use appropriate tools to ensure their safety and that of the snake. In this case, an experienced snake handler was called to remove a spitting cobra, but they were ill-equipped. During the removal, the venom was sprayed across the handler's face, and some of it entered their eye, resulting in ophthalmic envenomation. The handler promptly irrigated their eye, but medical treatment was still necessary. This report highlights the risks and consequences of ophthalmic injury and the importance of wearing appropriate eye protection and taking due care when dealing with venomous species, particularly those that can spit venom. It serves as a reminder that accidents can happen at any time and experienced snake handlers are not exempt from the risks.
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  • Article
    Keszthelyi L.
    Nature. 1976 Nov 11;264(5582):197-8.
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  • Article
    Collyer TA, Smith KE.
    Soc Sci Med. 2020 11;264:113330.
    Research on health inequalities and health disparities has grown exponentially since the 1960s, but this expansion has not been matched by an associated sense of progress. Criticisms include claims that too much research addresses well-trodden questions and that the field has failed to gain public and policy traction. Qualitative studies have found researchers partly attribute these challenges to fragmentation resulting from disciplinary and methodological differences. Yet, empirical investigation ('research on research') is limited. This study addresses this gap, employing mixed-methods to examine, at scale, how and why this field is defined by insular research clusters. First, bibliometric analysis identifies and visualizes the 250 most-connected authors. Next, an algorithm was used to identify clustering via citation links between authors. We used researcher profiling to ascertain authors' geographical and institutional locations and disciplinary training, examining how this mapped onto clusters. Finally, causes of siloing were investigated via semi-structured interviews with 45 researchers. The resulting 'atlas' of health inequalities and health disparities research identifies eight clusters of authors with varying degrees of connectedness. No single factor neatly describes observed fragmentation, health equity scholars exhibit a diverse disciplinary backgrounds, and geographical, institutional, and historical factors appear to intersect to explain siloed citation patterns. While the configuration of research activity within clusters potentially helps render questions scientifically manageable, it affirms perceptions of the field as fragmented. We draw on Thomas Kuhn and Sheila Jasanoff to position results within theoretical pictures of scientific progress. Newcomers to the field can use our findings to orient themselves within the many streams of health equity scholarship, and existing health equity scholars can use the atlas to move beyond existing geo-disciplinary networks. However, although stronger cross-cluster engagement would be likely to improve insights, the complex nexus of factors underlying the field's structure will likely make this challenging in practice.
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  • Article
    Ferreira MP, Castro CB, Honorato J, He S, Gonçalves Guimarães Júnior W, Esmieu C, Castellano EE, de Moura AF, Truzzi DR, Nascimento OR, Simonneau A, Marques Netto CGC.
    Dalton Trans. 2023 Aug 15;52(32):11254-11264.
    Copper nitrite reductase mimetics were synthesized using three new tridentate ligands sharing the same N,N,N motif of coordination. The ligands were based on L-proline modifications, attaching a pyridine and a triazole to the pyrrolidine ring, and differ by a pendant group (R = phenyl, n-butyl and n-propan-1-ol). All complexes coordinate nitrite, as evidenced by cyclic voltammetry, UV-Vis, FTIR and electron paramagnetic resonance (EPR) spectroscopies. The coordination mode of nitrite was assigned by FTIR and EPR as κ2O chelate mode. Upon acidification, EPR experiments indicated a shift from chelate to monodentate κO mode, and 15N NMR experiments of a Zn2+ analogue, suggested that the related Cu(II) nitrous acid complex may be reasonably stable in solution, but in equilibrium with free HONO under non catalytic conditions. Reduction of nitrite to NO was performed both chemically and electrocatalytically, observing the highest catalytic activities for the complex with n-propan-1-ol as pendant group. These results support the hypothesis that a hydrogen bond moiety in the secondary coordination sphere may aid the protonation step.
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  • Article
    Gu B, Du Y, Chen B, Zhao R, Lu H, Xu Q, Guo C.
    ACS Appl Mater Interfaces. 2022 Mar 09;14(9):11264-11272.
    An effective combination of smart materials plays an important role in charge transfer and separation for high photoelectric conversion efficiency (PCE) and stable solar cells. Black phosphorus quantum dots (BPQDs) have been revealed as a direct band gap semiconductor with ultrahigh conductivity, which have been explored in the present work as an additive component to a precursor solution of SnO2 nanoparticles that can effectively improve the performance of SnO2 electron transport layer (ETL)-based perovskite solar cells. Such a device can yield a high PCE of 21% with the SnO2/BPQDs mixed ETL, which is higher than those of perovskite solar cells based on SnO2 single layer (18.2%), BPQDs/SnO2 bilayer (19.5%), and SnO2/BPQDs bilayer (20.5%) samples. The mixed samples still possess good stability of more than 90% efficiency after 1000 h under AM 1.5G lamp irradiation and negligible hysteresis. It is found that the strong interaction of BPQDs with SnO2 can not only modify the defects inherent to the SnO2 layer but also inhibit the oxidation of BPQDs. This work provides a promising functional material for SnO2 ETL-based perovskite solar cells and proves that the BPQD-based modification strategy is useful for designing other solar cells with high performance.
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