Search results for "dioxide"
showing 10 items of 1250 documents
Carboxytherapy in dermatology.
2022
Abstract Carboxytherapy is a medical technique during which a sterile gas—carbon dioxide—is injected into the subdermal tissue. The utility of carbon dioxide injections has enhanced the practical relevance of carboxytherapy as a method for the management of multiple disorders. We have evaluated its use in the treatment of dermatologic conditions by searching electronic databases (ie, MEDLINE and PubMed) for contributions in the English language through January 2021. Carboxytherapy provides an attractive aesthetic option in skin rejuvenation, atrophic scars, striae distensae (stretch marks), cellulite-fibrolipodystrophy adhesions after liposuction, and certain types of alopecia. We discuss t…
Principles and Technique of Foam Sclerotherapy and Its Specific Use in the Treatment of Venous Leg Ulcers
2011
Invention of foam sclerotherapy has significantly changed the current phlebological practice. Compared with liquid sclerosants, obliterating foam is more efficient, especially for the closure of larger veins. This review discusses clinical aspects of foam sclerotherapy with a focus on its use for the treatment of venous leg ulceration, including the rationale for its use in the treatment of these chronic wounds, physicochemical mechanisms responsible for stability and disintegration of sclerosant foam, pathomechanism of neurologic adverse events seen after foam sclerotherapy, and techniques that can increase efficacy of this procedure and lower frequency of adverse events.
Combined Epidural and General Anesthesia Prevents Excessive Oxygen Consumption Postoperatively
1994
In the postoperative period patients are at risk of excessive oxygen consumption (VO2). However, patients suffering from cardiovascular disease may be unable to increase their oxygen transport capacity sufficiently and may be especially vulnerable to tissue hypoxia as part of the reaction to intraoperative stress. During the last 10 years contradictory results concerning the benefits of a combined epidural and light general anesthesia have been published. Some of the results indicate that postoperative catabolism maybe depressed and that the neuroendocrine response to stress may be inhibited by such a combined technique1,2. We studied the effect of a combined epidural and light general anes…
280 Impact of ozone air pollution on ischemic cerebral and cardiac events in Dijon, France
2011
Background There is strong evidence that short-term exposure to ozone (O3) is associated with respiratory disease and death, but the effects of short-term exposure to ozone on ischemic heart and cerebrovascular disease have not been clearly established. Methods Daily levels of urban O3 pollution, the incidence of first-ever, recurrent, fatal and non-fatal ischemic cerebro-vascular events (ICVE) and myocardial infarction (MI) were compared using a bi-directional case-crossover design analysis. We analysed 1 574 ICVE and 913 MI that occurred in Dijon, France from 2001 to 2007. Sulphur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), particulate matter with an aerodiameter of 10μg/…
First combined flux chamber survey of mercury and CO2 emissions from soil diffuse degassing at Solfatara of Pozzuoli crater, Campi Flegrei (Italy): M…
2014
Abstract There have been limited studies to date targeting gaseous elemental mercury (GEM) flux from soil emission in enriched volcanic substrates and its relation with CO 2 release and tectonic structures. In order to evaluate and understand the processes of soil–air exchanges involved at Solfatara of Pozzuoli volcano, the most active zone of Campi Flegrei caldera (Italy), an intensive field measurement survey has been achieved in September 2013 by using high-time resolution techniques. Soil–air exchange fluxes of GEM and CO 2 have been measured simultaneously at 116 points, widely distributed within the crater. Quantification of gas flux has been assessed by using field accumulation chamb…
Fundamental limits for transmission modulation in VO2 metasurfaces
2022
The interest in dynamic modulation of light by ultra-thin materials exhibiting insulator–metal phase transition, such as VO 2 , has rapidly grown due to the myriad industrial applications, including smart windows and optical limiters. However, for applications in the telecommunication spectral band, the light modulation through a thin VO 2 film is low due to the presence of strong material loss. Here, we demonstrate tailored nanostructuring of VO 2 to dramatically enhance its transmission modulation, reaching a value as high as 0.73, which is 2 times larger than the previous modulation achieved. The resulting designs, including free-topology optimization, demonstrate the fundamental limit i…
Non-stationary nature of SO2 degassing at Etna’s North-east crater (Italy).
2012
Investigating Etna’s long-term SO2 flux behaviour has led to important conclusions on the structure of the volcano’s magma feeding system, magma production (and degassing) rates, and causes for the excess degassing behaviour. Nonetheless, our knowledge of the short-term (timescales of seconds to a few hours) behaviour of magmatic volatiles (e.g., bubble coalescence, separate ascent and surface bursting of gas-rich bubbles) in the volcano’s upper feeding conduit system is still fragmentary, and based on indirect evidences (petrologic-textural data, observation of geophysical signals , physical modelling and laboratory experiments). In the past, direct gas flux measurements at Etna have been ta…
The role of biosilica in the osteoprotegerin/RANKL ratio in human osteoblast-like cells
2010
Abstract Earlier studies have demonstrated that biosilica, synthesized by the enzyme silicatein, induces hydroxyapatite formation in osteoblast-like SaOS-2 cells. Here we study the effect of biosilica on the expressions of osteoprotegerin [OPG] and the receptor activator for NF-κB ligand [RANKL] in the SaOS-2 cell model. We show that during growth of SaOS-2 cells on biosiliceous matrices hydroxyapatite formation is induced, while syntheses of cartilaginous proteoglycans and sulfated glycosaminoglycans are down-regulated. Furthermore, quantitative real-time RT-PCR analysis revealed a strong time-depended increase in expression of OPG in biosilica exposed SaOS-2 cells while the steady-state e…
Bio-silica and bio-polyphosphate: applications in biomedicine (bone formation)
2012
Bio-silica represents the main mineral component of the sponge skeletal elements (siliceous spicules), while bio-polyphosphate (bio-polyP), a multifunctional polymer existing in microorganisms and animals acts, among others, as reinforcement for pores in cell membranes. These natural inorganic bio-polymers, which can be readily prepared, either by recombinant enzymes (bio-silica and bio-polyP) or chemically (polyP), are promising materials/substances for the amelioration and/or treatment of human bone diseases and dysfunctions. It has been demonstrated that bio-silica causes in vitro a differential effect on the expression of the genes OPG and RANKL, encoding two mediators that control the …
Alcohol-Selective Oxidation in Water under Mild Conditions via a Novel Approach to Hybrid Composite Photocatalysts
2015
Abstract The oxidation of alcohols to carbonyl compounds in a clean fashion (i.e., with water as a solvent or under solvent‐free conditions, and using O2 or H2O2 as the primary oxidant) is the subject of considerable research efforts. A new approach for the selective oxidation of soluble aromatic alcohols in water under mild conditions via a novel composite photocatalyst has been developed. The catalyst is synthesized by grafting 4‐(4‐(4‐hydroxyphenylimino)cyclohexa‐2,5dienylideneamino)phenol and silver nanoparticles onto the surface of moderately crystalline titanium dioxide. The titanium dioxide‐based composite was first extensively characterized and then employed in the catalytic oxidati…