1,721,658 research outputs found
Cold pressed grape seed oils: a study on their phenolic content by HPLC/DAD/MS and HPLC/MS/MS
No full textSince the 50s of last century, the production of oil extracted from seeds and oleaginous fruits has increased significantly becoming of great importance in the agricultural worldwide economy. The increased demand has resulted in a significant expansion of the area under oilseed crops. The edible oils are commonly classified into oils extracted from fruit and from oilseeds. This latter group include byproducts of industrial processes as the grape seed from wine industry. In Italy almost all the oilseeds are usually extracted with hexane and commercialized only as refined oils. The refining processes that apply high temperatures induce almost a total disappearance of the phenolic compounds from the oil as also confirmed by a screening on different samples before and after these treatments1. Nevertheless, in several countries of South America, mainly Argentina and Chile the cold-pressed grape seed oil is widely used for human consumption; its pleasant and characteristic taste make it suitable, as for olive oils, to be consumed as crude condiment to flavor dishes. To date, scant data are available on the content of minor polar compounds in these unrefined oils2. Aim of this work was to investigate on the phenolic fraction of two cold pressed grape seed oils from different provenience. The oils were extracted with ethanol/acidic water 7/3 to recover lignans and other more simple phenols. The alcoholic extracts were then analysed on reverse phase by HPLC/DAD/MS on reverse phase and by targeted MS/MS experiments operating in negative ionization mode. The presence of lignans, in particular pinoresinol and one isobar was confirmed in both these oil in comparable amounts to those found in a commercial olive oil (close to 5 mg/L). Some hydroxycinnamic acids and flavonols such as kaempferol and its derivatives were identified by the help of their spectra. Moreover, the MS/MS experiments allowed to identify two ethyl esters of p-coumaric acid and p-methoxy cinnamic acid not identified to date in grape seed oil.
These preliminary data suggest future investigations on a wide number of samples to define the phenolic profiles, to evaluate the antioxidant capacity and the health benefits of the cold pressed grape seed oil
Back to the Future: Robotic Microsurgery
Full text linkToday, robotics has become the gold standard in the operating
room for several procedures and surgical specialties.
However, microsurgery has not been touched to date other
than the limited application of the da Vinci Surgical System,
not focused on microanastomosis. Differently from da Vinci,
which aims to facilitate minimally invasive procedures by
providing improved vision and dexterity to the conventional
laparoscopic approach, new microsurgical robots are now
designed and being introduced to provide improved precision
for anastomosis. Thanks to elimination of tremor and
high scaling potential, robotics in microsurgery probably
will acquire increasing value as the current trend in submillimetric
anastomosis will be confirmed in the clinical
practice
Superthin Flap Harvesting Procedure: Technical Note
Full text linkThe anterolateral thigh (ALT) flap has been extensively discussed in the literature as it allows for a wide variety and depth of tissues for complex wound coverage. Thanks to many cadaveric and angiographic studies of the subdermal plexus, it is to date ascertained that tailoring ALT thickness can be safely performed without compromising flap outcomes or causing additional morbidity. Recently, the authors applied and described a simpler, safer, and less time-consuming superthin ALT perforator (ALTP) free flap harvesting technique. The aim of this article is to show the versatility of the adipofascial flap harvested around the chosen perforators, which allowed us to safely expand the usage of ALTP superthin flaps
Development of a New Robotic Platform for Microsurgery
No full textWhile robotics has primarily penetrated laparoscopic surgery with the product offering of Intuitive Surgical and to a lesser extent orthopedic, spinal, and brain surgery, plastic surgery has remained largely untouched by robotics to date, partially due to the absence of a dedicated robotic technology. In this chapter, we examine the technology gaps that have contributed to this scenario and describe how the resulting criteria for a robotic platform for reconstructive microsurgery have propelled an end-user-driven development of a robotic platform with wristed robotic microinstruments for open surgery
Recurrent digital fibromatosis of childhood
No full textThe Author report on a case of recurrent digital fibromatosis in a chil
Propeller Flaps in the Upper Extremity: Arm and Forearm Reconstruction
No full textThe propeller flap is an island of skin that is raised on its pedicle (most commonly a single perforator) and can rotate 180 degrees to cover a soft tissue defect. Thanks to these features, the propeller flap brings reliable tissue from outside of the zone of injury while sparing the main vessels of the upper extremity. This technique limits the donor site to the same limb, captures skin characterized by having the same color and texture, does not necessarily need a microvascular anastomosis, and overall reduces the operating time and surgical cost. Our intent here is to present 27 cases with different soft tissue defects of the upper arm and forearm that have been successfully reconstructed using propeller flaps. The surgical technique, with emphasis on the anatomy of the upper arm, is described. In particular, use of a freestyle approach to customize a perforator-based propeller flap to cover defects from small to medium size is detailed. In our experience, the use of a perforator propeller flap in the upper extremity for resurfacing represents both a very reliable and aesthetically pleasant option
DESIGN OF THE PHASING TRAJECTORY FROM A LOW LUNAR ORBIT TO NEAR RECTILINEAR HALO ORBIT
No full textThe paper describes the preliminary design of a phasing trajectory in a cislunar environment, where the third body perturbation is considered non-negligible. The working framework is the one proposed by the ESA’s Heracles mission in which a passive target station is in a Near Rectilinear Halo Orbit and an active vehicle must reach that orbit to start a rendezvous procedure. In this scenario the authors examine three different ways to design such phasing maneuver under the circular restricted three-body problem hypotheses: Lambert/differential correction, Hohmann/differential correction and optimization. The three approaches are compared in terms of ∆V consumption, accuracy and time of flight. The selected solution is also validated under the more accurate restricted elliptic three-body problem hypothesis
Relative Motion Dynamics in Restricted Three-Body Scenarios
No full textThis paper discusses the derivation and simplification of equation sets for the relative motion dynamics characterization in the restricted three-body problem. As opposed to previous models proposed in the literature, the relative motion is studied in a frame local to the target spacecraft, the local-vertical local-horizon frame, and spacecraft state is expressed with respect to the primary about which they are orbiting. The exact description of the relative dynamics is derived, as well as simplified equation sets based on both the elliptic and the circular restricted three-body problems. The accuracy of the simplified sets is analyzed by means of extensive numerical simulations on a realistic rendezvous scenario with a target on lunar orbit
Relative Motion Dynamics with Arbitrary Perturbations in the Local-Vertical Local-Horizon Reference Frame
No full textAccurate models for spacecraft relative dynamics are essential to the design of high-precision control and long-term estimation. In the literature, numerous analytical models have been proposed that describe, with different degrees of accuracy, the relative dynamics in presence of specific perturbations. These models however may be limited for future missions, like long-baseline formation flying, that will require analytical formulations capable of considering the influence of different perturbations at the same time, in order to meet the high-demanding mission requirements. The aim of this Note is to provide a general and flexible framework for the inclusion of arbitrary perturbations into the equations of relative motion. The framework decouples the perturbations influence from the Keplerian component of the motion, so that designers can include the perturbations of interest according to the mission scenario. In the future, the proposed framework might be used by autonomous spacecraft for real-time reconfiguration of the guidance system in response to a changed operating scenario. The inclusion of arbitrary zonal harmonics perturbations and atmospheric drag into our framework is discussed
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