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81.
Ysmael Verde-Gmez Elizabeth Montiel-Macías Ana María Valenzuela-Muiz Ivonne Alonso-Lemus Mario Miki-Yoshida Karim Zaghib Nicolas Brodusch Raynald Gauvin 《Materials》2022,15(10)
In the past few decades, nanostructured carbons (NCs) have been investigated for their interesting properties, which are attractive for a wide range of applications in electronic devices, energy systems, sensors, and support materials. One approach to improving the properties of NCs is to dope them with various heteroatoms. This work describes the synthesis and study of sulfur-added carbon nanohorns (S-CNH). Synthesis of S-CNH was carried out by modified chemical vapor deposition (m-CVD) using toluene and thiophene as carbon and sulfur sources, respectively. Some parameters such as the temperature of synthesis and carrier gas flow rates were modified to determine their effect on the properties of S-CNH. High-resolution scanning and transmission electron microscopy analysis showed the presence of hollow horn-type carbon nanostructures with lengths between 1 to 3 µm and, diameters that are in the range of 50 to 200 nm. Two types of carbon layers were observed, with rough outer layers and smooth inner layers. The surface textural properties are attributed to the defects induced by the sulfur intercalated into the lattice or bonded with the carbon. The XRD patterns and X-ray microanalysis studies show that iron serves as the seed for carbon nanohorn growth and iron sulfide is formed during synthesis. 相似文献
82.
The growing demand for wood-based panels for buildings and furniture and the increasing worldwide concern for reducing the pressure on forest resources require alternatives to wood raw materials. The agricultural industry not only can provide raw materials from non-wood plants but also numerous residues and side streams. This review supplies an overview of the availability, chemical composition, and fiber characteristics of non-wood lignocellulosic materials and agricultural residues, i.e., grow care residues, harvest residues, and process residues, and their relevance for use in wood panel manufacturing. During the crop harvest, there are millions of tons of residues in the form of stalks, among other things. Usually, these are only available seasonally without using storage capacity. Process residues, on the other hand, can be taken from ongoing production and processed further. Fiber characteristics and chemical composition affect the panel properties. Alternatives to wood with long fibers and high cellulose content offer sufficient mechanical strength in different panel types. In general, the addition of wood substitutes up to approximately 30% provides panels with the required strength properties. However, other parameters must be considered, such as pressing temperature, adhesive type, press levels, and pretreatments of the raw material. The search for new raw materials for wood panels should focus on availability throughout the year, the corresponding chemical requirements and market competition. Panel type and production process can be adapted to different raw materials to fit niche products. 相似文献
83.
Michael D. Dub Christopher A. Rothfusz Ahmed K. Emara Matthew Hadad Peter Surace Viktor E. Krebs Robert M. Molloy Nicolas S. Piuzzi 《Current reviews in musculoskeletal medicine》2022,15(4):311
Purpose of Review8.5 to 50% of total joint arthroplasty (TJA) patients are reported to have preoperative malnutrition. The narrative review identifies the relationship between preoperative malnutrition for TJA patients and postoperative outcomes as well as the use of perioperative nutritional intervention to improve postoperative complications.Recent FindingsBiochemical/laboratory, anthropometric, and clinical measures have been widely used to identify preoperative nutritional deficiency. Specifically, serum albumin is the most prevalent used marker in TJA because it has been proven to be correlated with protein-energy malnutrition due to the surgical stress response. However, there remains a sustained incidence of preoperative malnutrition in total knee arthroplasty (TKA) and total hip arthroplasty (THA) patients due to a lack of agreement among the available nutritional screening tools and utilization of isolated laboratory, anthropometric, and clinical variables. Previous investigations have also suggested preoperative malnutrition to be a prognostic indicator of complications in general, cardiac, vascular, and orthopaedic surgery specialties.SummarySerum albumin, prealbumin, transferrin, and total lymphocyte count (TLC) can be used to identify at-risk patients. It is important to employ these markers in the preoperative setting because malnourished TKA and THA patients have shown to have worse postoperative outcomes including prolonged length, increased reoperation rates, increased infection rates, and increased mortality rates. Although benefits from high-protein and high-anti-inflammatory diets have been exhibited, additional research is needed to confirm the use of perioperative nutritional intervention as an appropriate treatment for preoperative TJA patients. 相似文献
84.
vom Saal FS Akingbemi BT Belcher SM Birnbaum LS Crain DA Eriksen M Farabollini F Guillette LJ Hauser R Heindel JJ Ho SM Hunt PA Iguchi T Jobling S Kanno J Keri RA Knudsen KE Laufer H LeBlanc GA Marcus M McLachlan JA Myers JP Nadal A Newbold RR Olea N Prins GS Richter CA Rubin BS Sonnenschein C Soto AM Talsness CE Vandenbergh JG Vandenberg LN Walser-Kuntz DR Watson CS Welshons WV Wetherill Y Zoeller RT 《Reproductive toxicology (Elmsford, N.Y.)》2007,24(2):131-138
85.
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87.
Olivier Rouvière Philippe Puech Raphaële Renard-Penna Michel Claudon Catherine Roy Florence Mège-Lechevallier Myriam Decaussin-Petrucci Marine Dubreuil-Chambardel Laurent Magaud Laurent Remontet Alain Ruffion Marc Colombel Sébastien Crouzet Anne-Marie Schott Laurent Lemaitre Muriel Rabilloud Nicolas Grenier 《The lancet oncology》2019,20(1):100-109
88.
Vanderzwalmen P Hiemer A Rubner P Bach M Neyer A Stecher A Uher P Zintz M Lejeune B Vanderzwalmen S Cassuto G Zech NH 《Reproductive biomedicine online》2008,17(5):617-627
Spermatozoa selection at high magnification before intracytoplasmic sperm injection seems to be positively associated with pregnancy rates after day 3 embryo transfers. The aim was to demonstrate an association between the presence of vacuoles in sperm nuclei and the competence of embryos to develop to day 5. Grading of spermatozoa at x 6000-x 12,500 magnification: grade I, no vacuoles; grade II, or=1 large vacuole; grade IV, large vacuoles with other abnormalities. The outcome of embryo development in a group of 25 patients after sibling oocyte injection with the four different grades of spermatozoa showed no significant difference in embryo quality up to day 3. However, the occurrence of blastocyst formation was 56.3 and 61.4% with grade I and II spermatozoa respectively, compared with 5.1% with grade III and 0% with grade IV respectively (P < 0.001). Spermatozoa selection at high magnification using Nomarski interference contrast is useful to identify more precisely the size and the number of nuclear vacuoles that greatly exert a negative effect on embryo development to the blastocyst stage. These observations confirm previous studies pointing to possible 'early and late paternal effects', both of which may have an impact on early embryonic development. 相似文献
89.
We report two brothers, their mother and a maternal cousin who had a distinctive facial phenotype, mild brachydactyly and prominence of the interphalangeal joints. One brother and the mother also had multiple ventricular extrasystoles. Six other relatives in four generations were probably affected on the basis of history and family photographs. We also report a further individual from a different family with a similar facial phenotype, Pierre-Robin sequence, tapering fingers and multiple ventricular extrasystoles. These families have some similarities to those reported by Stoll et al. in a single family, showing dominant inheritance. Our patients would seem to have the same or a related condition. 相似文献
90.