5,142 research outputs found
Instantaneous Kinematics and Singularities of Two Types of Under-Actuated Parallel Wrists
No full textS-(nS)PU-SPU and S-(nS)PU-2SPU are two out of three types of under-actuated wrists that are generated from the “ordinary” wrists of type S-3SPU (fully-parallel wrists), by replacing a spherical pair (S) with a nonholonomic spherical pair (nS) according to the rules stated in [1]. Position analysis, controllability, and path planning of these two wrist types have been addressed and solved in two previous papers [2, 3] of this author. Their kinetostatics and singularity analysis have not been addressed, yet; and they are studied in this paper.
[1] Grosch, P., Di Gregorio, R., and Thomas, F., 2010, “Generation of under-actuated manipulators with nonholonomic joints from ordinary manipulators,” ASME J. of Mechanisms and Robotics, 2(1): 011005-(8 pages).
[2] Di Gregorio R., 2011, “Under-Actuated Nonholonomic Parallel Wrists,” In: Proc. of the 13th World Congress in Mechanism and Machine Science (IFToMM 2011), Guanajuato, México, 19-25 June, 2011, Paper No. A12-264
[3] Di Gregorio, R., 2011, “On the S-(nS)PU-SPU and S-(nS)PU-2SPU under-actuated wrists,” Procs. of the ASME 2011 International Design Engineering Technical Conference & Computers and Information in Engineering Conference, IDETC/CIE 2011, August 28-31, 2011, Washington (DC, USA), Paper No.: DETC2011-47541
Kinetostatics of S-(nS)PU-SPU and S-(nS)PU-2SPU Nonholonomic Parallel Wrists
No full textS-(nS)PU-SPU and S-(nS)PU-2SPU are two types of nonholonomic wrists that are generated from the “ordinary” wrists of type S-3SPU (fully parallel wrists (FPW)), by replacing a spherical pair (S) with a nonholonomic spherical pair (nS) according to the rules stated by Grosch et al. (2010, “Generation of Under-Actuated Manipulators With Nonholonomic Joints From Ordinary Manipulators,” ASME J. Mech. Rob., 2(1), p. 011005). Position analysis, controllability, and path planning of these two wrist types have been addressed and solved in two previous papers (Di Gregorio, R., 2012, “Type Synthesis of Underactuated Wrists Generated From Fully-Parallel Wrists,” ASME J. Mech. Des., 134(12), p. 124501 and Di Gregorio, R., 2012, “Position Analysis and Path Planning of the S-(nS)PU-SPU and S-(nS)PU-2SPU Underactuated Wrists,” ASME J. Mech. Rob., 4(2), p. 021006) of this author, which demonstrated that simple closed-form formulas are sufficient to control their configuration and to implement their path planning. Their kinetostatics and singularity analysis have not been addressed, yet; and they are studied in this paper. Here, the singularity analysis will reveal, for the first time, the existence of a somehow novel type of singularities, here named “jamming singularity,” that jams the platform motion in some directions and that is also present in all the parallel manipulators with SPU limbs (e.g., Gough-Stewart platforms) where it can be considered a particular type of “leg singularity.” Moreover, the static analysis will demonstrate that the reaction forces due to the static friction, in the nonholonomic constraint, can be controlled in the same way as the generalized forces exerted by the actuators, and that the possible slippage, in the same constraint, can be easily monitored and compensated
Agli agapeti: un ciclo di componimenti di Gregorio Nazianzeno
No full textEsame della tradizione manoscritta e a stampa del ciclo di componimenti di Gregorio Nazianzeno ‘Agli agapeti’. Prima edizione critica e prima traduzione in lingua italiana del ciclo stesso
Progetto per la Città della Musica sul lungofiume di Pescara.
No full textIl riciclo dell'ex inceneritore di Pescara è stato inteso come opportunità di innescare un processo più ampio di rinnovamento urbano teso alla graduale riconversione dell’area industriale dismessa in una nuova area strategica destinata alla cultura e al tempo libero
Polifunzionalità dell'assegno di divorzio e condizioni patrimoniali dei coniugi
No full textThe article describes the recent trend of the jurisprudence on the entitlement and quantification of the divorce allowance, with compensatory and rebalancing nature. The author hopes for the recognition of the validity of nuptial agreements to prevent family disputes on the divorce allowanc
Sistemi progettuali ed esecutivi nei cantieri pittorici di Gregorio XIII
No full textNel riesaminare i cicli pittorici commissionati in Vaticano da Gregorio XIII si affronta il tema della direzione dei cantieri e delle procedure adottate nella progettazione e nell'esecuzione degli affreschi. In particolare si avanzano proposte attributive riguardanti i numerosi artisti intervenuti nella loggia gregoriana e si analizzano alcuni disegni e studi preparatori in relazione al progetto di destinare a Biblioteca la lunga galleria poi denominata delle "Carte geografiche"
Sanità: pubblica, privata o non profit?. Indagine comparata sul ruolo del Terzo Settore nei sistemi sanitari occidentali e nell’assistenza sanitaria del Veneto
No full textDato per acquisito il progressivo ingresso degli enti non profit nel mondo della sanità, con un’operatività strettamente legata alle regole di mercato e di libera concorrenza, si tratta di stabilire se un modello integrato “pubblico – privato – non profit” sia in grado di produrre un servizio sanitario qualitativamente performante, economicamente sostenibile e più vicino alle esigenze dell’utenza. Si tratta inoltre di verificare se un modello siffatto conservi la sua validità indipendentemente dal quadro giuridico – istituzionale (Servizio Sanitario Nazionale essenzialmente pubblico ed accentrato o decentrato, Servizio Sanitario essenzialmente privato in cui lo Stato fa unicamente da regolatore), da quello economico – finanziario, dagli assetti organizzativi locali e dalla proprietà o controllo degli “asset”
Tossicità sistemica degli anestetici locali. Trattamento con emulsione lipidica
No full textBackground: Lipid emulsion infusion reverses cardiovascular compromise due to local anesthetic overdose in laboratory and clinical settings.
The author compared the efficacy of resuscitation from bupivacaine-induced asystole using lipid emulsion infusion versus epinephrine, vasopressin, combination of epinephrine and vasopressin, and saline control in a prospective randomized animal study.
Methods: Bupivacaine was infused in male Spregue-Dawley rats anesthetized with isoflurane, producing asystole in all subjects. Rats were ventilated with 100% oxygen, given chest compression, and randomized to receive 30% lipid emulsion, vasopressin, epinephrine alone or combined with vasopressin, and saline.
Treatment boluses were repeated at 2.5 and 5 minutes for a native rate-pressure product less than 20% baseline. Electrocardiogram and arterial blood pressure were monitored continuously and at 10 min arterial blood gas, central venous oxygen saturation and blood lactate were measured.
Results: Lipid infusion resulted in higher rate-pressure product, pH and central venous oxygen saturation than in vasopressors groups and in control group at 10
min. Metrics indicated better tissue perfusion in lipid group than in the others group. Epinephrine treatment caused persistent ventricular ectopy in all subjects. Vasopressin and epinephrine were associated with developing of pulmonary edema.
Conclusion: Lipid emulsion in this rat model provide superior hemodynamic and metabolic recovery from bupivacaine-induced cardiac arrest than do vasopressors. Vasopressin and epinephrine were associated with adverse outcomes. Systolic pressure was not an useful metric in the vasopressors group. Further studies are required to optimize the clinical management of systemic local anesthetic toxicity.E’ stato precedentemente dimostrato il recupero di attività cardiaca spontanea dopo l’infusione di una emulsione lipidica (30% soy oil emulsion) in seguito ad arresto cardiaco bupivacaina-indotto sia in vivo sia in modelli sperimentali di cuore isolato.
Numerosi case reports sono stati pubblicati sull’utilizzo clinico dell’emulsione lipidica nella rianimazione di pazienti in arresto cardiaco in seguito ad overdose di anestetico locale.
Le linee guida 2005 dell’American Heart Association (AHA/ACLS resucitation protocol) prevedono l’utilizzo di una dose di 40 U di vasopressina, al posto della prima o seconda dose di epinefrina, come farmaco di prima linea nel trattamento dell’arresto cardiaco.
Abbiamo studiato l’efficacia dell’emulsione lipidica versus i farmaci suggeriti dai protocolli ACLS in un modello sperimentale di arresto cardiaco bupivacaina-indotto in ratti. Sono stati analizzati parametri emodinamici, metabolici ed elettrocardiografici. L’emulsione lipidica è risultata superiore, in termini di sopravvivenza, parametri
emodinamici e metabolici, all’adrenalina, alla vasopressina e alla loro associazione nel trattamento dell’arresto cardiaco indotto da un’overdose di bupivacaina. Ulteriori studi sono necessari per confermare queste osservazioni e soprattutto per determinare eventuali implicazioni sul piano clinico
Problemi di interpretazione e prassi esecutiva nelle sonate dell'autografo I-Pca 1888-1 di Giuseppe Tartini
No full textABSTRACT (ENGLISH VERSION)
“Problems of Interpretation and Performance Practice in the Autograph Sonatas by Giuseppe Tartini (I-Pca 1888-1)”
The starting point and the principal objective of this research was the edition of the manuscript I-Pca, 1888-1, an important autograph of Violin music written by Giuseppe Tartini (ca. 1750). The aim was of reconstructing the whole set of 31 complete sonatas as recommended by P. Braianrd (1961, 1970).
That has been possible working on the array of Roman numbers written by Tartini to arrange his sonatas in a gradual order. After Sonata XXV this number array was interrupted, and, in the second part of the manuscript, you can only recognize six sonatas: one sonata from one tip given by the author, five more thanks to some exact spots showing similar handwriting.
This kind of reconstruction has led to a new editorial proposal, which provides new and unexpected details of music practice, new tips and musical suggestions written by Tartini himself as well as problematic notational habits not yet examined in former studies and editions (Brainard, 1959; Guglielmo, 1970; Farina, 1980).
The unaccompanied Violin music by Tartini was studied like a sort of unicum in European history of music, not comparable to the great north European tradition (from Baltzar, Biber, Westhoff to Bach, Pisendel and Geminiani). The present study wants to fill this ´critical gap´ between Tartini and the great representatives of north European music, focusing on the first part of the quoted autograph, introducing 13 Solos with a written bass line. To achieve such a result, all possible connections between the Tartini’s Solos with a bass and the contemporary north European accompained Solos tradition were taken into consideration. The first and most important connection is his attested contact with the Court of Frederick the Great, to whom he sent (via Francesco Algarotti) a collection of Solos with a “basso per cerimonia”, today lost, which was for sure taken from the above-named autograph. (see “Lettera di Giuseppe Tartini al Sig. Conte Fr. Algarotti”, Padova, 24 febbraio 1750).
The research was concentrated on a large amount of German sources exploring the accompaniment of a Solo for violin, in order to define a sort of north European musical milieu (C. P. E. Bach, Quantz, Löhlein, Kürzinger, Eisel, L. Mozart) which was not so far from the ´Tartinian manner´ (as seen in direct scholars like Nardini, or further disciples like Campagnoli, Barbella).
This sort of “bass” was intended like a bass bowed melodic instrument (probably close to the so called “viola di spala (sic)”, “violoncello da spalla”, “basset[t]e” or, as a synonym, “violoncello”), and not as a thorough bass (for the harpsichord). This particular bass line was also used by Tartini to accompany a violin (notated with single or double string), in order to reach new effects of timbre.
All the bass lines in the Paduan autograph were analyzed, with a view to obtaining a ´map´ of Giuseppe Tartini’s counterpunctual methods, so as to define what kind of “bass” (continuo, seguente or both) he used, how, where, when, and why.
Padova, 31 gennaio 2013 Gregorio Carrar
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