634 research outputs found
The Influence of the Thermodynamic Cycle Parameters on the Performance of Refrigerators and Freezers
Manipulation of ultracold atomic mixtures using microwave techniques
We used microwave radiation to evaporatively cool a mixture of of 133Cs and
87Rb atoms in a magnetic trap. A mixture composed of an equal number (around
10^4) of Rb and Cs atoms in their doubly polarized states at ultracold
temperatures was prepared. We also used microwaves to selectively evaporate
atoms in different Zeeman states.Comment: 9 pages, 6 figure
CoQ10 and vitamin A supplementation support voice rehabilitation. A double-blind, randomized, controlled, three-period cross-over pilot study
Objectives: To evaluate the effectiveness of an adjuvant therapy (CoQ10 in its watersoluble form and vitamin A) in supporting voice rehabilitation in a large group of patients with muscle tension dysphonia (MTD). Study Design: Twelve-week, double-blind, randomized, controlled, three-period crossover pilot study. The primary endpoint was the change in the Dysphonia Severity Index (DSI) over the 12-week study period. Secondary endpoints were the changes in the subcomponents of DSI, including MPT, F0-high, I-low, and jitter. Exploratory endpoints were the changes in the Shimmer and in Voice Handicap Index (VHI). Methods: Patients were randomly assigned in a 1:1 ratio to two counter-balanced arms. Group A (ADJ-PLA) patients were administered QTer 300 mg and Vit A acetate 500.000 Ul/g 1 mg twice daily for a 4-week intervention period, followed by a 4-week period of wash-out, and then were submitted to a last 4-week period of placebo. Patients in Group B (PLB-ADJ) were given the treatment period in reverse order. Both groups received a 45-min voice therapy in a group format once a day for 4 weeks during the first and the second active periods. The therapy was held during the wash-out period. Results: The analysis of main time effect indicated a trend toward recovery of vocal function regardless of group assignment. A significant time by group effect was found on DSI [F = 3.4 (2.5, 80.5), p = 0.03], F0-high [F = 4.5 (2.6, 82.9), p = 0.008] and Shimmer [F = 3.6 (1.5, 46.9), p = 0.048], under CoQ10 and Vit A treatment, with a small effect size. There was no significant time by group effect on the other study measures, namely MPT, I-low, VHI. Conclusions: A trend toward recovery of vocal function was observed in all the patients, likely due to voice rehabilitation. The improvement of DSI was greater under CoQ10 and Vitamin treatment, indicating a more pronounced improvement of vocal quality under adjuvant therapy. The study protocol was reviewed and approved by the Ethics Committee of Policlinico Umberto I Hospital, Rome, Italy Rif. 3069/13.02.2014
Can the current state support mechanisms help the growth of renewable energies in wind markets?
The aim of this paper is to provide evidence on the effectiveness of the current state support mechanism incentive adopted by the Italian government in the wind market. In particular, this paper intends to investigate the effectiveness of the auction mechanism as an incentive tool for renewable sources as required by the transposition of Directive 2009/28/EC. In order to demonstrate the economic and financial feasibility of a typical wind-sector investment, we performed a scenario analysis (Monte Carlo simulation) determining a 52,500 Net Present Value (NPV) by varying the key underlying variables of the investment. The results show that with the mechanism currently in place the percentage of positive leveraged NPV is approximately equal to 70%. Despite the state contribution provided through the âFeed-in tariffâ mechanism, the profitability of wind projects is not always successful, and this problem could be amplified by the slowness of the authorization procedures. The article offers prime reflections for scholars and policy makers who have long been committed to promoting sustainable development and important considerations on the introduction of further incentive models
A sapphire monolithic differential accelerometer as core sensor for gravity gradiometric geophysical instrumentation
Gradiometric gravimetry is a survey technique widely used in geological structure investigation. This work demonstrates
the feasibility of a new class of low frequency accelerometers for geodynamics studies and space applications.
We present the design features of a new low noise single-axis differential accelerometer; the sensor is suitable
to be used in a Gravity Gradiometer (GG) system for land geophysical survey and gravity gradient measurements.
A resolution of 1 Eötvös (1 Eö=10â9sâ2) at one sample per second is achievable in a compact, lightweight
(less than 2 kg) portable instrument, operating at room temperature. The basic components of the sensor are two
identical rigidly connected accelerometers separated by a 15-cm baseline vector and the useful signal is extracted
as the subtraction of the two outputs, by means of an interferometric microwave readout system. The structure will
be engraved in a monocrystal of sapphire by means of Computer-Numerically-Controlled (CNC) ultrasonic machining:
the material was chosen because of its unique mix of outstanding mechanical and dielectric properties
Circular Economy Impact Analysis on Stock Performances: An Empirical Comparison with the Euro Stoxx 50Âź ESG Index
Environmental issues have a considerable impact in all economic sectors, also influencing financial markets. As a result, environmental, social, and governance (ESG) awareness is rising in the financial sector. In this perspective, the concept of circular economy (CE) assumes central relevance. The aim of our study is to investigate the relationship between CE strategies and market performance; to this end, we use ESG scores as a proxy for CE. Our initial assumption is that since CE is a component of the âEâ factorâin that it can generate positive and measurable environmental impactsâthen it can be associated with the ESG score. Therefore, we can methodologically overcome the lack of a specific score related to CE. We use a preselection model based on historical performance by verifying the percentages of the presence of stocks in the two selected indices, namely ESG Euro Stoxx 50Âź and Euro Stoxx 50-ESG. Overall, we find that ESG profiles have a positive impact on stock performance, although ESG scores do not express higher performance per se. Furthermore, our analysis shows that, to date, there is no evidence that CE initiatives can influence stock returns
Low-temperature gas from marine shales: wet gas to dry gas over experimental time
Marine shales exhibit unusual behavior at low temperatures under anoxic gas flow. They generate catalytic gas 300° below thermal cracking temperatures, discontinuously in aperiodic episodes, and lose these properties on exposure to trace amounts of oxygen. Here we report a surprising reversal in hydrocarbon generation. Heavy hydrocarbons are formed before light hydrocarbons resulting in wet gas at the onset of generation grading to dryer gas over time. The effect is moderate under gas flow and substantial in closed reactions. In sequential closed reactions at 100°C, gas from a Cretaceous Mowry shale progresses from predominately heavy hydrocarbons (66% C5, 2% C1) to predominantly light hydrocarbons (56% C1, 8% C5), the opposite of that expected from desorption of preexisting hydrocarbons. Differences in catalyst substrate composition explain these dynamics. Gas flow should carry heavier hydrocarbons to catalytic sites, in contrast to static conditions where catalytic sites are limited to in-place hydrocarbons. In-place hydrocarbons and their products should become lighter with conversion thus generating lighter hydrocarbon over time, consistent with our experimental results
Concettualizzazione e contestualizzazione dei beni culturali archeologici
This report describes the observations made while developing a new methodology for historic surveys used for the re-contextualisation of archaeological finds. This particular methodology avails itself of both traditional historic surveys as well as the representation of knowledge through ontology. The methodology described here was developed in reference to specific cases of re-contextualisation of archaeological artefacts from Pompeii which are now in the National Archaeological Museum in Naples
The relationship between maternal reflexive functions and joint attention in neurotypical children
Joint Attention (JA) can be defined as the coordination of attentional orienting between two persons towards a common object. It develops in typically developing children between 6 and 18 months of age across two phases: Initiating Joint Attention (IJA) and Responding to Joint Attention (RJA). For instance, a parent can initiate JA by pointing to an object and the child can respond by moving her eye gaze towards the parentâs pointing. JA represents one of the first precursors of the Theory of Mind (ToM) implying the personâs ability to think and reason about own and another person's mental states, inferring thoughts, beliefs, intentions and desires. Less is clear, instead, on the relationship between the development of JA abilities in children and the mentalizing abilities of mothers. In the present study, we aimed at investigating the relationships between the infantâs (age range: 15 and 20 months) behaviours relating to IJA and the maternal Reflexive Functions (RF). The results showed a significant correlation between these two skills, thus suggesting that the reflective capacity of mothers can play an important role in development of milestones of the childâs social cognition
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