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991.
We wish for robots to manipulate objects and move flexibly in three-dimensional spaces. We describe a robot that can move on a web of surfaces oriented around arbitrary directions in three-space and a set of control algorithms that implements motion in three-dimensions. The robot can manipulate objects in three dimensions while moving, by using the same set of physical resources and control algorithms. This robot is an inchworm-like robot with a simple, modular, and flexible design. Finally, we discuss our experiments. 相似文献
992.
G Finucci M Bianchini P Micheli A Marconi C Mastria G Guayana 《Canadian Metallurgical Quarterly》1997,52(12):1447-1450
Benign ulceration of the cecum is an uncommon lesion that was originally described by Cruveilhier in 1832. Etiology is unknown and symptomatology not pathognomonic. Pre-operative and intraoperative diagnosis is rare and difficult. Definitive diagnosis is usually obtained by histologic evaluation of the surgical specimen after a right hemicolectomy performed for a suspect of a neoplasm of the cecum. The authors present 7 cases of cecal ulcers and suggest that preoperative diagnosis may be due after a colonoscopy with biopsy. This examination may be performed only in that cases that appear without symptoms of acute abdomen. The authors suggest also to perform right hemicolectomy. 相似文献
993.
Roberta Zuntini Elena Bonora Laura Maria Pradella Laura Benedetta Amato Michele Vidone Sara De Fanti Irene Catucci Laura Cortesi Veronica Medici Simona Ferrari Giuseppe Gasparre Paolo Peterlongo Marco Sazzini Daniela Turchetti 《International journal of molecular sciences》2021,22(11)
The NBN gene has been included in breast cancer (BC) multigene panels based on early studies suggesting an increased BC risk for carriers, though not confirmed by recent research. To evaluate the impact of NBN analysis, we assessed the results of NBN sequencing in 116 BRCA-negative BC patients and reviewed the literature. Three patients (2.6%) carried potentially relevant variants: two, apparently unrelated, carried the frameshift variant c.156_157delTT and another one the c.628G>T variant. The latter was subsequently found in 4/1390 (0.3%) BC cases and 8/1580 (0.5%) controls in an independent sample, which, together with in silico predictions, provided evidence against its pathogenicity. Conversely, the rare c.156_157delTT variant was absent in the case-control set; moreover, a 50% reduction of NBN expression was demonstrated in one carrier. However, in one family it failed to co-segregate with BC, while the other carrier was found to harbor also a probably pathogenic TP53 variant that may explain her phenotype. Therefore, the c.156_157delTT, although functionally deleterious, was not supported as a cancer-predisposing defect. Pathogenic/likely pathogenic NBN variants were detected by multigene panels in 31/12314 (0.25%) patients included in 15 studies. The risk of misinterpretation of such findings is substantial and supports the exclusion of NBN from multigene panels. 相似文献
994.
This study develops and analyzes an original methodology for the simulation and prediction of space heating energy consumption in buildings connected to a district heating system, characterized by lack of individual control systems for end-users. The identification of the input parameters is based on both classical engineering equations and statistical analysis of collected data. Two main factors play important roles in the model: (i) climate and (ii) human behavior. Model validation was undertaken through the analysis of field data collected during the winter, via a monitoring system working in a partially-controlled district heating system. The comparison between the results obtained with the proposed model versus classical methods points out the possibility to implement, using the proposed methodology, management policies for a district that offer significant cost-effective energy savings opportunities. 相似文献
995.
Preparation and characterization of blends of recycled polystyrene with cassava starch 总被引:1,自引:0,他引:1
Tais A. P. F. Pimentel Jussara A. Durães Adriana L. Drummond Daniela Schlemmer Rosana Falcão Maria José Araújo Sales 《Journal of Materials Science》2007,42(17):7530-7536
Secondary recycling is an alternative to solve at least part of the worldwide pollution problem caused by persistence of petrochemical
plastic materials in the environment. In this work we report the secondary recycling of disposable polystyrene (PS) using
cassava starch (Manihot esculenta Crantz) and a natural plasticizer extracted from a palm tree of the Amazon: Buriti (Mauritia flexuosa L.) oil. 13C-NMR spectroscopy reveals incorporation of the oil in the polymer matrix. Although phase separation had occurred, SEM depicts
a very good dispersion of the thermoplastic starch (TPS) in the PS matrix with distinct domains. Thermal analyses indicate
smaller thermal stability of the PS/TPS blends compared to PS and that possess intermediate characteristics between the pure
PS and TPS, confirmed by DRX. Kinetic study shows a lowering of the activation energy for the thermal degradation of the blends. 相似文献
996.
997.
Mattia P. Arena Graziano Caggianiello Daniela Fiocco Pasquale Russo Michele Torelli Giuseppe Spano Vittorio Capozzi 《International journal of molecular sciences》2014,15(2):3025-3039
Currently, the majority of prebiotics in the market are derived from non-digestible oligosaccharides. Very few studies have focused on non-digestible long chain complex polysaccharides in relation to their potential as novel prebiotics. Cereals β-glucans have been investigated for immune-modulating properties and beneficial effects on obesity, cardiovascular diseases, diabetes, and cholesterol levels. Moreover, β-glucans have been reported to be highly fermentable by the intestinal microbiota in the caecum and colon, and can enhance both growth rate and lactic acid production of microbes isolated from the human intestine. In this work, we report the effects of food matrices containing barley β-glucans on growth and probiotic features of four Lactobacillus strains. Such matrices were able to improve the growth rate of the tested bacteria both in unstressed conditions and, importantly, after exposure to in vitro simulation of the digestive tract. Moreover, the effect of β-glucans-containing food on bacterial adhesion to enterocyte-like cells was analyzed and a positive influence on probiotic-enterocyte interaction was observed. 相似文献
998.
Dr. Daniela Schulz Prof. Dr. Andrea Rentmeister 《Chembiochem : a European journal of chemical biology》2014,15(16):2342-2347
Over recent years, click reactions have become recognized as valuable and flexible tools to label biomacromolecules such as proteins, nucleic acids, and glycans. Some of the developed strategies can be performed not only in aqueous solution but also in the presence of cellular components, as well as on (or even in) living cells. These labeling strategies require the initial, specific modification of the target molecule with a small, reactive moiety. In the second step, a click reaction is used to covalently couple a reporter molecule to the biomolecule. Depending on the type of reporter, labeling by the click reaction can be used in many different applications, ranging from isolation to functional studies of biomacromolecules. In this minireview, we focus on labeling strategies for RNA that rely on the click reaction. We first highlight click reactions that have been used successfully to label modified RNA, and then describe different strategies to introduce the required reactive groups into target RNA. The benefits and potential limitations of the strategies are critically discussed with regard to possible future developments. 相似文献
999.
Krassimir Garbev Günter Beuchle Uwe Schweike Daniela Merz Olga Dregert Peter Stemmermann 《Journal of the American Ceramic Society》2014,97(7):2298-2307
New cementitious materials based on calcium hydrosilicate hydrates were recently developed as potential substitutes for ordinary portland cement, but with a reduced CO2 footprint. The materials are produced by hydrothermal processing of SiO2 and Ca(OH)2, giving rise to calcium silicate hydrates, followed by mechanical activation of the latter via cogrinding with various siliceous materials. Thus, the chemical composition in terms of C/S ratio could be adjusted over a broad range (1–3). In this study the synthesis of a previously unknown cementitious material produced via the combination of mechanical activation in a laboratory mill and thermal treatment of a mixture of quartz and hydrothermally synthesized calcium silicate hydrates: α‐Ca2[HSiO4](OH) (α‐C2SH) and Ca6[Si2O7](OH)6 (jaffeite) are reported. It forms independently of the type of mill used (eccentric vibrating mill, vibration grinding mill) after thermal treatment of the ground materials at 360°C–420°C. The new material is X‐ray amorphous and possesses a CaO/SiO2 ratio of 2. A characteristic feature in regards to the silicate anionic structure is the increased silicate polymerization (up to 27% Si2O7 dimers) as revealed by the trimethylsilylation method. Infrared (IR) spectra show a very broad absorption band centered at about 935 cm?1. Another characteristic feature is the presence of ~2.5 wt% H2O as shown by thermogravimetry (TG) coupled with IR spectroscopy. As this water is bound mostly as hydroxyl to Ca, we refer to this new cementitious material as calcium‐oxide–hydroxide–silicate (C–CH–S). Calorimetric measurements point to a very high hydraulic reactivity which is beyond that for typical C2S materials. The influence of the type of grinding on the thermal behavior of α‐C2SH upon its transformation into water‐free Ca2SiO4 modifications is discussed. 相似文献
1000.
Dr.‐Ing. Christian Schnitzer Dr. Daniela Kruse Marina Lazar Markus Priske Dr.‐Ing. Axel Kobus 《化学,工程师,技术》2014,86(5):589-593
Organic Solvent Nanofiltration is a relatively new unit operation in fluid processing. It addresses a multitude of applications in all sectors of the chemical industry. The benefit for the customer can be a different one depending on the application, therefore, multiple process examples are discussed. Within these, organic solvent nanofiltration can be applied either as a standalone separation process or as a hybrid process in combination with other thermal separation methods. 相似文献