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排序方式: 共有94条查询结果,搜索用时 15 毫秒
1.
Genovese V. Guglielmelli E. Mantuano A. Ratti G. Sabatini A.M. Dario P. 《Electronics letters》1995,31(8):632-633
The authors describe their approach to the design of redundant proximity sensor systems that are capable of extracting geometrical information about the surrounding environment and perceiving other relevant features of the reflecting objects, e.g. colour. Potential applications of the proposed sensorial systems are in the field of robotics and autonomous mobility 相似文献
2.
This paper introduces a novel framework for the design, modeling and control of a Micro Aerial Vehicle (MAV). The vehicle’s
conceptual design is based on biologically-inspired principles and emulates a dragonfly (Odonata–Anisoptera). We have taken
inspiration from the flight mechanism features of the dragonfly and have developed indigenous designs in creating a novel
version of a Flapping Wing MAV (FWMAV). The MAV design incorporates a complex mechanical construction and a sophisticated
multi-layered, hybrid, linear/non-linear controller to achieve extended flight times and improved agility compared to other
rotary wing and FWMAV Vertical Take Off and Landing (VTOL) designs. The first MAV prototype will have a ballpark weight including
sensor payload of around 30 g. The targeted lifting capability is about twice the weight. The MAV features state of the art
sensing and instrumentation payload, which includes integrated high-power on-board processors, 6DoF inertial sensors, 3DoF
compasses, GPS, embedded camera and long-range telemetry capability. A 3-layer control mechanism has been developed to harness
the dynamics and attain complete navigational control of the MAV. The inner-layer is composed of a ‘quad hybrid-energy controller’
and two higher layers are at present, implementing a linear controller; the latter will be replaced eventually with a dynamic
adaptive non-linear controller. The advantages of the proposed design compared to other similar ones include higher energy
efficiency and extended flight endurance. The design features elastic storage and re-use of propulsion energy favoring energy
conservation during flight. The design/modeling of the MAV and its kinematics & dynamics have been tested under simulation
to achieve desired performance. The potential applications for such a high endurance vehicle are numerous, including air-deployable
mass surveillance and reconnaissance in cluster and swarm formations. The efficacy of the design is demonstrated through a
simulation environment. The dynamics are verified through simulations and a general linear controller coupled with an energy
based non-linear controller is shown to operate the vehicle in a stable regime. In accordance with specified objectives a
prototype is being developed for flight-testing and demonstration purposes. 相似文献
3.
Elisa Boschetti Leonardo Caporali Roberto DAngelo Carolina Malagelada Anna Accarino Maria Teresa Dotti Roberta Costa Giovanna Cenacchi Loris Pironi Rita Rinaldi Vincenzo Stanghellini Stefano Ratti Lucia Manzoli Valerio Carelli Roberto De Giorgio 《International journal of molecular sciences》2022,23(15)
mitochondrial neuro-gastrointestinal encephalomyopathy (MNGIE) is a rare genetic disorder characterized by thymidine phosphorylase (TP) enzyme defect. The absence of TP activity induces the imbalance of mitochondrial nucleotide pool, leading to impaired mitochondrial DNA (mtDNA) replication and depletion. Since mtDNA is required to ensure oxidative phosphorylation, metabolically active tissues may not achieve sufficient energy production. The only effective life-saving approach in MNGIE has been the permanent replacement of TP via allogeneic hematopoietic stem cell or liver transplantation. However, the follow-up of transplanted patients showed that gut tissue changes do not revert and fatal complications, such as massive gastrointestinal bleeding, can occur. The purpose of this study was to clarify whether the reintroduction of TP after transplant can recover mtDNA copy number in a normal range. Using laser capture microdissection and droplet-digital-PCR, we assessed the mtDNA copy number in each layer of full-thickness ileal samples of a naive MNGIE cohort vs. controls and in a patient pre- and post-TP replacement. The treatment led to a significant recovery of gut tissue mtDNA amount, thus showing its efficacy. Our results indicate that a timely TP replacement is needed to maximize therapeutic success before irreversible degenerative tissue changes occur in MNGIE. 相似文献
4.
P. Ratti und K. -H. Habermehl 《Zeitschrift für Jagdwissenschaft》1977,23(4):188-213
Zusammenfassung An 328 Steinwildschädeln aus allen Teilen Graubündens wurde eine Altersbeurteilung durchgeführt. Als geeignet erwiesen sich hierfür der Durchbruch und der Wechsel der Zähne, die Abnutzung der Schneide- und Backenzähne sowie die Altersmerkmale an den Hörnern (Hornlänge, Jahresfurchen und Schmuckknoten).Darüber hinaus wurden das Wachstum verschiedener Kopfknochen und der Verknöcherungszeitpunkt einiger Schädelnähte als Altersmerkmal getestet.An den Schneidezahnwurzeln des Steinwildes konnte eine altersabhängige Zementzonenschichtung nachgewiesen werden, die in Form von Jahresringen zu erkennen ist.
Die Abhandlung konnte in dem vorliegenden Umfange Aufnahme finden, da seitens des Jagd- und Fischereiinspektorats des Kantons Graubünden ein entsprechender Druckkostenzuschuß gewährt wurde.-Die Schriftleitung 相似文献
Summary An age assessment was carried out on the skulls of 328 ibex from all districts of Graubünden. The eruption and replacement of teeth, the erosion of incisors and molars and the age characteristics on the horns (length, annual growth ridges and horn nodes) proved ideal for the purpose.In addition, the growth of various skull bones and the time of ossification of some cranial sutures were tested as age indicators. Cementum layers are deposited on the incisor roots of the ibex, the stratification of which may be regarded as a form of annual rings.
Résumé Une analyse de l'âge fut réalisée grâce à 328 crânes de Bouquetin provenant de toutes les régions du Graubünden. Dans ce but, l'éruption et le remplacement des dents, l'attrition des incisives et des molaires ainsi que la configuration des cornes (longueur, cannelures, bourrelets) se sont avérés adéquates. En outre, on testa la croissance de différents os du crâne et le moment d'ossification de certaines sûtures crâniennes comme critères de détermination de l'âge.On put mettre en évidence un dépôt de cerne de cément sur la racine dentaire correspondant à des cernes annuels.
Die Abhandlung konnte in dem vorliegenden Umfange Aufnahme finden, da seitens des Jagd- und Fischereiinspektorats des Kantons Graubünden ein entsprechender Druckkostenzuschuß gewährt wurde.-Die Schriftleitung 相似文献
5.
Felipe Sánchez Carrillo Linda Saucier Cristina Ratti 《International Journal of Food Properties》2017,20(3):573-584
Thermal properties of duck fatty liver (foie gras), foie gras emulsion and fatty liver fat, as well as regular duck fat, were determined as a function of temperature. Density of foie gras and foie gras fat and emulsion at 20°C was measured as 947, 836, and 928 kg/m3, respectively. Differential scanning calorimetry thermograms for foie gras fat resulted in melting points ranging from –20 to 40°C. Values for the specific heat at 65°C for the fatty liver, its emulsion and fat, and duck fat were 1.79, 2.38, 1.71, and 2.48 J/g°C, respectively. Thermal conductivity of foie gras (organ) and its emulsion at 40°C was determined as 0.330 and 0.428 W/m°C, respectively. Mathematical models based on composition and temperature were developed for all the thermal properties obtained in this work. 相似文献
6.
A Ratti 《Canadian Metallurgical Quarterly》1980,66(7-8):481-484
7.
Giulia Bernardini Maurizio Comanducci Stefania Bambini Giovanni Renzone Andrea Scaloni Giovanna Morelli Mark Achtman Giulio Ratti Annalisa Santucci 《Proteomics. Clinical applications》2009,3(10):1251-1254
We previously described the first reference map for the proteome of one strain of serogroup A Neisseria meningitidis (MenA), a major cause of epidemic meningitis in humans. As a preliminary finding, in that work we noted that 2‐DE protein maps of closely related MenA isolates from different epidemics spreads could be easily compared to detect minor differences and that 2‐DE phenotypes attributable to the well‐known epidemiological marker tbpB agreed with the genoclouds model of MenA epidemiological variation during pandemic waves. We explored here the possibility that an extended comparative study of 2‐DE maps of isolates representative of the nine genoclouds described by Achtman and collaborators could be used to discriminate between strains otherwise undistinguishable. We showed the example of 14 proteins with different 2‐DE spot patterns in different genoclouds that could be considered as putative tracers for alike‐strains discrimination. We introduce the novel concept that comparative proteomics can be useful in identifying new epidemiological markers for N. meningitidis. 相似文献
8.
Tocopherols and tocotrienols as free radical-scavengers in refined vegetable oils and their stability during deep-fat frying 总被引:1,自引:0,他引:1
The aim of this study was to assess the effect of total tocopherols and tocotrienols of refined vegetable oils on oil radical-scavenging activity and to investigate the stability of the various homologues during the deep-fat frying of French fries. Eight different refined vegetable oils were investigated, having variable levels of natural tocopherols and tocotrienols. A direct correlation between the radical-scavenging capacity of the oils, measured by the DPPH test, and the total content of natural tocopherols and tocotrienols was found. Frying experiments showed that the stability of the different tocopherols and tocotrienols present in the refined vegetable oils basically depend on two factors: the fatty acid composition of the oil, in particular polyunsaturated fatty acid content, and the kind of tocopherol and tocotrienol homologues present. The more oxidizable the oil, on the basis of fatty acid composition, the more stable were the tocopherolic antioxidants. Among the different homologues, γ-tocotrienol in palm super olein proved to be the least stable during the deep-fat frying, thus preserving the other homologues. 相似文献
9.
10.
Egg white (albumen) is a rich source of protein and is widely used in confectionary industry for its wonderful foaming ability. Foam-mat freeze drying is one of the promising methods of drying, which tries to utilize the advantages of both freeze drying and foam-mat drying to produce better quality egg white powder. Preliminary experiments showed that the stability of foams made with egg white alone is not adequate for foam-mat freeze drying. Experiments were thus conducted using different stabilizers (methyl cellulose, propylene glycol alginate, and xanthan gum) to optimize foam stability. Bubble size distribution was determined using microscopy to understand foam structure. This article will discuss the effect of stabilizers on the stability of egg white foam and possible mechanisms involved. The results showed that xanthan gum at 0.125% provided sufficient stability for freeze drying. 相似文献