Vertical axis wind turbine drive train transient dynamics

Start up of a vertical axis wind turbine causes transient torque oscillations in the drive train with peak torques which may be over two and one half times the rated torque of the turbine. A computer code, based on a lumped parameter model of the drive train, was developed and tested for the low cost 17 meter turbine; the results show excellent agreement with field data. The code was used to predict the effect of a slip clutch on transient torque oscillations. It was demonstrated that a slip clutch located between the motor and brake can reduce peak torques by thirty eight percent

The assembly and use of tethered bilayer lipid membranes (tBLMs)

© Springer Science+Business Media New York 2015. Because they are firmly held in place, tethered bilayer lipid membranes (tBLMs) are considerably more robust than supported lipid bilayers such as black lipid membranes (BLMs) (Cornell et al. Nature 387(6633): 580–583, 1997). Here we describe the procedures required to assemble and test tethered lipid bilayers that can incorporate various lipid species, peptides, and ion channel proteins

Evidence of the Key Role of H<inf>3</inf>O⁺ in Phospholipid Membrane Morphology

© 2016 American Chemical Society. This study explains the importance of the phosphate moiety and H3O+ in controlling the ionic flux through phospholipid membranes. We show that despite an increase in the H3O+ concentration when the pH is decreased, the level of ionic conduction through phospholipid bilayers is reduced. By modifying the lipid structure, we show the dominant determinant of membrane conduction is the hydrogen bonding between the phosphate oxygens on adjacent phospholipids. The modulation of conduction with pH is proposed to arise from the varying H3O+ concentrations altering the molecular area per lipid and modifying the geometry of conductive defects already present in the membrane. Given the geometrical constraints that control the lipid phase structure of membranes, these area changes predict that organisms evolving in environments with different pHs will select for different phospholipid chain lengths, as is found for organisms near highly acidic volcanic vents (short chains) or in highly alkaline salt lakes (long chains). The stabilizing effect of the hydration shells around phosphate groups also accounts for the prevalence of phospholipids across biology. Measurement of ion permeation through lipid bilayers was made tractable using sparsely tethered bilayer lipid membranes with swept frequency electrical impedance spectroscopy and ramped dc amperometry. Additional evidence of the effect of a change in pH on lipid packing density is obtained from neutron reflectometry data of tethered membranes containing perdeuterated lipids

Experimental modelling of a parachute-type tidal energy converter

European Regional Development Fund (ERDF

Cooperation in wild Barbary macaques: factors affecting free partner choice

A key aspect of cooperation is partner choice: choosing the best available partner improves the chances of a successful cooperative interaction and decreases the likelihood of being exploited. However, in studies on cooperation subjects are rarely allowed to freely choose their partners. Group-living animals live in a complex social environment where they can choose among several social partners differing in, for example, sex, age, temperament, or dominance status. Our study investigated whether wild Barbary macaques succeed to cooperate using an experimental apparatus, and whether individual and social factors affect their choice of partners and the degree of cooperation. We used the string pulling task that requires two monkeys to manipulate simultaneously a rope in order to receive a food reward. The monkeys were free to interact with the apparatus or not and to choose their partner. The results showed that Barbary macaques are able to pair up with a partner to cooperate using the apparatus. High level of tolerance between monkeys was necessary for the initiation of successful cooperation, while strong social bond positively affected the maintenance of cooperative interactions. Dominance status, sex, age, and temperament of the subjects also affected their choice and performance. These factors thus need to be taken into account in cooperative experiment on animals. Tolerance between social partners is likely to be a prerequisite for the evolution of cooperation

Optimization studies on accelerator sample components for energy management purposes

The large amount of energy required to operate large-scale facilities with particle accelerators within has been considered as one of the important research topics over the past years. This sheds light on the importance of the research field of energy management that entitles, with a view to long-term operations, the implementation of smart and sustainable technologies. One of the key technologies in accelerators are superconductor (SC)-based designs. The vanishing electrical resistance together with the ability to provide field values well above those from conventional conductors is the main motivation behind exploiting superconducting wires in building coils and magnets for large-scale accelerators. However, these superconductors can also quench under certain conditions, driving the wires into the normal state and potentially allowing for overheating and destruction of the conductor material and/or the whole design. This work will present the results of optimization-based analyses performed on accelerator SC-sample components aiming at goal designs that are more energy efficient at a reference operational field or current. A compromise between getting the best performance for excellent science from a design (with superconductivity preserved and safe operation maintained) and reducing its power consumption (and eventually its effective cost) will be addressed too

First cases of combined full robotic partial nephrectomy and colorectal resections: Results and new perspectives

Background: Nowadays the robotic platform is widespread in general surgery, urology, and gynecology. Combined surgery may represent an alternative to sequential procedures and it allows the treatment, at the same time, of coexisting lesions; in this perspective, full-robotic multiorgan surgery is starting to gain interest from surgeons worldwide. Methods: Between April and June 2019, two patients presenting with synchronous colorectal and kidney cancers underwent, respectively, full-robotic right colectomy with right partial nephrectomy and anterior rectal resection with left partial nephrectomy. Surgeries were performed by both the general surgery and urology team. Results: No intraoperative complications were registered and the postoperative course was uneventful in both cases. Conclusions: Combined multiple organ surgery with full robotic technique is safe and offers oncological adequate results. A multi-team surgical pre-planning is mandatory to reduce invasiveness and operative time. To the best of our knowledge, these are the first reports of full robotic partial nephrectomy combined with colorectal procedures

Psychobiological evidence of the stress resilience fostering properties of a cosmetic routine

Everyday life psychosocial stressors contribute to poor health and disease vulnerabilty. Means alternative to pharmacotherapy that are able to foster stress resilience are more and more under the magnifying glass of biomedical research. The aim of this study was to test stress resilience fostering properties of the self-administration of a cosmetic product enriched with essential oils. On day 0, fourty women, 25-50 years old, self-administered both the enriched cosmetic product (ECP) and a placebo one (PCP). Then, women were randomized for daily self-administration (from day 1 to 28) of either ECP (n = 20) or PCP (n = 20). On day 29, subjects underwent a psychosocial stress test (PST). Autonomic (heart rate and its variability) and neuroendocrine (salivary cortisol) parameters were assessed both on day 0 and 29. All subjects filled a number of psychological questionnaires in order to quantify anxiety, perceived stress, and mood profile, and were videorecorded during PST for non-verbal behavior evaluation. A single application of ECP produced an acute potentiation of cardiac parasympathetic modulation, which was not observed when placebo was used. Prolonged self-administration of ECP induced: (i) a dampening of the cortisol rise produced by PST, (ii) a reduction of state anxiety, (iii) a favorable change in mood profile, and (iv) a reduction of non-verbal behavior patterns that signal anxiety, motivational conflict and avoidance. In conclusion, this study suggests that the self-administration of a cosmetic cream enriched with essential oils should be considered as a stress resilience fostering strategy due to its favorable physiological, neuroendocrine and psychological effects