Bimetallic nanostructures show exciting potential as materials for effective photothermal hyperthermia therapy. We report the seed-mediated synthesis of palladium-gold (Pd-Au) nanostructures containing multiple gold nanocrystals on highly branched palladium seeds. The nanostructures were synthesized via the addition of a gold precursor to a palladium seed solution in the presence of oleylamine, which acts as both a reducing and a stabilizing agent. The interaction and the electronic coupling between gold nanocrystals and between palladium and gold broadened and red-shifted the localized surface plasmon resonance absorption maximum of the gold nanocrystals into the near-infrared region, to give enhanced suitability for photothermal hyperthermia therapy. Pd-Au heterostructures irradiated with an 808 nm laser light caused destruction of HeLa cancer cells in vitro, as well as complete destruction of tumor xenographs in mouse models in vivo for effective photothermal hyperthermia.

This article reports on the investigation of reactive magnetron sputtering of transparent, crystalline titanium dioxide films. The aim of this investigation is to determine a minimum substrate surface temperature Tsurf necessary to form crystalline TiO2 films with anatase structure. Films were prepared by dc pulsed reactive magnetron sputtering using a dual magnetron operating in bipolar mode and equipped with Ti(99.5) and ceramic Ti5O9 targets. The films were deposited on unheated glass substrates and their structure was characterized by x-ray diffraction and surface morphology by atomic force microscopy. Special attention is devoted to the measurement of Tsurf using thermostrips pasted to the glass substrate. It was found that (1) Tsurf is considerably higher (approximately by 100°C or more) than the substrate temperature Ts measured by the thermocouple incorporated into the substrate holder and (2) Tsurf strongly depends on the substrate-to-target distance ds-t, the magnetron target power loading, and the thermal conductivity of the target and its cooling. The main result of this study is the finding that (1) the crystallization of sputtered TiO2 films depends not only on Tsurf but also on the total pressure pT of sputtering gas (Ar+O2), partial pressure of oxygen pO2, the film deposition rate aD, and the film thickness h, (2) crystalline TiO2 films with well developed anatase structure can be formed at Tsurf=160°C and low values of aD≈5nm∕min, (3) the crystalline structure of TiO2 film gradually changes from (i) anatase through (ii) anatase+rutile mixture, and (iii) pure rutile to x-ray amorphous structure at Tsurf=160°C and pT=0.75Pa when pO2 decreases and aD increases above 5nm∕min, and (4) crystallinity of the TiO2 films decreases with decreasing h and Tsurf. Interrelationships between the structure of TiO2 film, its roughness, Tsurf, and aD are discussed in detail. Trends of next development are briefly outlined.

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Here we report a new, bench-top synthesis for iron/iron oxide core/shell nanoparticles via the thermal decomposition of Fe(η(5)-C(6)H(3)Me(4))(2). The iron/iron oxide core/shell nanoparticles are superparamagnetic at room temperature and show improved negative contrast in T(2)-weighted MR imaging compared to pure iron oxides nanoparticles, and have a transverse relaxivity (r(2)) of 332 mM(-1) s(-1).

Biocompatible iron nanoparticles exhibiting a high magnetic moment are potentially useful for a variety of biomedical applications. However, once exposed to air, iron nanoparticles partially oxidize, effectively reducing their magnetic performance. Here, near‐monodisperse iron nanocrystals were synthesized and oxidized on the surface to form iron/iron oxide core/shell nanoparticles. The presence of excess stabilizers was shown to stabilize the core/shell nanoparticles, thus preventing further oxidation. The advantage of these core/shell nanoparticles in biomedicine, is shown by greater cellular MRI contrast enhancement compared to pure iron oxides without increase in cytotoxicity.

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This paper provides a detailed description of the IBM SiGe BiCMOS and rf CMOS technologies. The technologies provide high-performance SiGe heterojunction bipolar transistors (HBTs) combined with advanced CMOS technology and a variety of passive devices critical for realizing an integrated mixed-signal system-on-a-chip (SoC). The paper reviews the process development and integration methodology, presents the device characteristics, and shows how the development and device selection were geared toward usage in mixed-signal IC development.

E‐cigarette or vaping product use–associated lung injury was recognized in the United States in the summer of 2019 and is typified by acute respiratory distress, shortness of breath, chest pain, cough, and fever, associated with vaping. It can mimic many of the manifestations of coronavirus disease 2019 (COVID‐19). Some investigators have suggested that E‐cigarette or vaping product use–associated lung injury was due to tetrahydrocannabinol or vitamin E acetate oil mixed with the electronic cigarette liquid. In experimental rodent studies initially designed to study the effect of electronic cigarette use on the cardiovascular system, we observed an E‐cigarette or vaping product use–associated lung injury‐like condition that occurred acutely after use of a nichrome heating element at high power, without the use of tetrahydrocannabinol, vitamin E, or nicotine. Lung lesions included thickening of the alveolar wall with foci of inflammation, red blood cell congestion, obliteration of alveolar spaces, and pneumonitis in some cases; bronchi showed accumulation of fibrin, inflammatory cells, and mucus plugs. Electronic cigarette users should be cautioned about the potential danger of operating electronic cigarette units at high settings; the possibility that certain heating elements may be deleterious; and that E‐cigarette or vaping product use–associated lung injury may not be dependent upon tetrahydrocannabinol, vitamin E, or nicotine.