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Giacomo Mariani
2020 Figshare  
Visual Algorithm Simulation (VAS) exercises are commonly used in Computer Science education to help learners understand the logic behind the abstractions used in programming. These exercises also present problems common in the daily work of Computer Science graduates. Aalto University uses the JSAV library to create VAS exercises and evaluate the solutions submitted by students. The evaluation process counts the amount of correct steps given by the user during the exercise. However, because
more » ... detailed data is not collected, teachers currently can not recreate and analyse the submitted solutions more in depth. This thesis presents the design, development and evaluation of an application prototype, which can be easily integrated in existing VAS exercises created with the JSAV library. The prototype is called Player Application, and it is designed as a service that can be easily integrated into other systems while still remaining independent. The Player Application consists of two main independent components: the Exercise Recorder and the Exercise Player. A third important contribution is the new JSON-based Algorithm Animation Language, which is designed to describe, structure and store the data collected from the VAS exercises. The prototype was successfully tested in an online environment by importing the Exercise Recorder into existing exercises and replaying the submitted solutions in the Exercise Player. The tests showed that its design and architecture were valid. Next, the aim is to create a mature application, which can be used at Aalto University and other institutions, in addition the prototype still needs further development to support more VAS exercise types.
doi:10.6084/m9.figshare.12624161 fatcat:u7nbj5yjxjcxxlga4mdognd34m

Coordination of Autonomous Vehicles: Taxonomy and Survey [article]

Stefano Mariani, Giacomo Cabri, Franco Zambonelli
2020 arXiv   pre-print
Mariani, Cabri, Zambonelli The trolley dilemma is expressed as follows: a trolley is advancing on a railway and is going to kill three persons that are in its trajectory.  ... 
arXiv:2001.02443v1 fatcat:cpr5qinibnbczfu5zekejpobja

Porphyrin Diacid-Polyelectrolyte Assemblies: Effective Photocatalysts in Solution

Sabine Frühbeißer, Giacomo Mariani, Franziska Gröhn
2016 Polymers  
Developing effective and versatile photocatalytic systems is of great potential in solar energy conversion. Here we investigate the formation of supramolecular catalysts by electrostatic self-assembly in aqueous solution: Combining positively charged porphyrins with negatively charged polyelectrolytes leads to nanoscale assemblies where, next to electrostatic interactions, π⁻π interactions also play an important role. Porphyrin diacid-polyelectrolyte assemblies exhibit a substantially enhanced
more » ... atalytic activity for the light-driven oxidation of iodide. Aggregates with the hexavalent cationic porphyrin diacids show up to 22 times higher catalytic activity than the corresponding aggregates under neutral conditions. The catalytic activity can be increased by increasing the valency of the porphyrin and by choice of the loading ratio. The structural investigation of the supramolecular catalysts took place via atomic force microscopy and small angle neutron scattering. Hence, a new facile concept for the design of efficient and tunable self-assembled photocatalysts is presented.
doi:10.3390/polym8050180 pmid:30979275 pmcid:PMC6431837 fatcat:c2vi4hkiwjgvjkgex7iibq5n3i


Giacomo Mauro D'Ariano, Cristian Mariani, Salvatore Veca
2017 Istituto Lombardo - Accademia di Scienze e Lettere - Incontri di Studio  
Il contributo di Cristian Mariani, studente dottorando in filosofia della fisica, verte su un'interpretazione plausibile del realismo strutturale, originariamente proposto da John Worrall come forma sofisticata  ... 
doi:10.4081/incontri.2017.280 fatcat:rxpq67fqy5bavftg5ckyxkjp3q

Predictors of Lymphatic Failure in Endometrial Cancer

Andrea Mariani, Maurice J. Webb, Gary L. Keeney, Giacomo Aletti, Karl C. Podratz
2002 Gynecologic Oncology  
Objective. The aim of this study was to identify determinants of lymphatic failure in patients with endometrial cancer after definitive primary treatment. Methods. We observed 142 relapses in endometrial cancer patients who had primary surgery at our institution during the decade before 1994. We defined lymphatic failure as a relapse occurring on the pelvic sidewall (PSW), para-aortic area (PAA), or other node-bearing area (i.e., groin, axilla, supraclavicular, mediastinal). Mean follow-up was
more » ... 2.8 months. Results. We observed 44 instances of lymphatic failure-6 on the PSW only, 16 in the PAA only, 12 concomitantly in the PAA and on the PSW, and 10 confined in other node-bearing areas. By univariate analysis, body mass index >30 kg/m 2 , para-aortic lymph node biopsy, cervical stromal invasion (CSI), positive adnexa, myometrial invasion >50%, primary tumor diameter >2 cm, positive peritoneal cytology, positive lymph nodes (pelvic and/or para-aortic), radiotherapy, grade 3 tumor, nonendometrioid histology, and lymph-vascular invasion (LVI) significantly (P < 0.05) correlated with lymphatic failure. However, on Cox regression analysis, only LVI (P < 0.01, relative risk [RR] ‫؍‬ 4.27), nodal involvement (P ‫؍‬ 0.02, RR ‫؍‬ 3.43), and CSI (P ‫؍‬ 0.049, RR ‫؍‬ 2.26) were independent predictors of lymphatic failure. Moreover, lymph node metastases (P ‫؍‬ 0.01, RR ‫؍‬ 19.82) and CSI (P ‫؍‬ 0.050, RR ‫؍‬ 3.57) independently predicted failure on the PSW, and only lymph node involvement (P < 0.01, RR ‫؍‬ 10.15) predicted relapse in the PAA. Conclusion. LVI, positive lymph nodes, and CSI were the strongest predictors of lymphatic failure in endometrial cancer (31% of patients with at least one of the above three variables had a failure at 5 years). Patients with none of the above three factors had an extremely low (<1%) risk of lymphatic failure. © 2002 Elsevier Science (USA)
doi:10.1006/gyno.2001.6550 pmid:11855884 fatcat:2364wotl75h7lmufgpbn4z4hza

Total aortic arch replacement with frozen elephant trunk (Thoraflex)

Luca Di Marco, Davide Pacini, Giacomo Murana, Carlo Mariani, Ciro Amodi, Roberto Di Bartolomeo
2018 ASVIDE  
Figure 3 Postoperative CT angiogram showing normal morphology of the Thoraflex hybrid prosthesis and of the supraaortic trunks reimplantation.
doi:10.21037/asvide.2018.548 fatcat:4gvgwiss7bfhrffrklexkymvaa

GaAs nanopillar-array solar cells employing in situ surface passivation

Giacomo Mariani, Adam C. Scofield, Chung-Hong Hung, Diana L. Huffaker
2013 Nature Communications  
Erratum: GaAs nanopillar-array solar cells employing in situ surface passivation Giacomo Mariani, Adam C. Scofield, Chung-Hong Hung & Diana L.  ... 
doi:10.1038/ncomms2509 pmid:23422665 pmcid:PMC3586731 fatcat:eldfap747vhr5nkfyin4ged7fa

Assessment of Prognostic Factors in Stage IIIA Endometrial Cancer

Andrea Mariani, Maurice J. Webb, Gary L. Keeney, Giacomo Aletti, Karl C. Podratz
2002 Gynecologic Oncology  
Objective. The objective of this study was the assessment of prognostic factors in stage IIIA endometrial cancer. Methods. Between 1984 and 1993, 51 patients with stage IIIA endometrial cancer received definitive treatment at our institution. Thirty-seven patients had positive peritoneal cytologic findings only (stage IIIA1), and 14 had adnexal or uterine serosal involvement (USI) (stage IIIA2). Median follow-up of surviving patients was 82.5 months. Results. The 5-year disease-related survival
more » ... (DRS) and recurrence-free survival (RFS) were 88 and 73%, respectively. RFS was 79% in patients with stage IIIA1 disease, compared with 57% in patients with stage IIIA2 disease (P ‫؍‬ 0.04). However, DRS did not significantly differ between stages IIIA1 and IIIA2. In the 37 patients with stage IIIA1 tumors, histologic grade 3, nonendometrioid histologic subtype, and lymphovascular invasion (LVI) significantly predicted a poor prognosis, with extraabdominal sites of failure (P < 0.05). Of the 22 patients who had stage IIIA1 disease with endometrioid histologic subtype and without LVI, none had recurrence [17 had whole abdominal irradiation (WAR) or intraperitoneal injection of 32 P, 2 had pelvic external radiotherapy (PRT)]. By contrast, of the 15 patients with either nonendometrioid histologic subtype or LVI, 9 (60%) had recurrence and 7 (47%) died of disease (12 had WAR or 32 P). An extraabdominal component was present in 7 of the 9 recurrences observed in this subgroup. Among the 14 patients with stage IIIA2 tumors (6 had WAR, 6 had PRT), those with USI had a 5-year DRS of 83% and a rate of extraabdominal failure of 83%, compared with 100 and 12.5% in patients without USI (P < 0.05). Conclusion. Patients with stage IIIA endometrial cancer who have endometrioid tumors, no LVI, and positive peritoneal cytologic findings as the only sign of extrauterine disease have an excellent prognosis. Nonendometrioid histologic subtype, LVI, and USI are strong predictors of distant failures and poor prognosis. Patients with either of these histologic factors should be considered candidates for systemic adjuvant therapy. © 2002 Elsevier Science (USA)
doi:10.1006/gyno.2002.6713 pmid:12079298 fatcat:3rsabzty6nfjnkzd4637iux4r4

Frozen Elephant Trunk in Aortic Arch Disease: Different Devices for Different Pathologies

Carlo Mariani, Giacomo Murana, Alessandro Leone, Luca Di Di Marco, Davide Pacini
2021 Medicina  
The frozen elephant trunk technique (FET) requires the use of a pre-assembled hybrid prosthesis consisting of a standard Dacron vascular portion to replace the aortic arch and a stent graft component, which is placed into the proximal descending thoracic aorta (DTA) anterogradely in the proximal descending thoracic aorta. In Europe, two hybrid prostheses are available: the E-evita Open Plus hybrid stent graft system provided by JOTEC (Hechingen, Germany) and the ThoraflexTM Hybrid (Vascutek,
more » ... hinnan Scotland). Recommendations for use are extensive pathologies of the arch in case of acute and chronic aortic dissection, degenerative aneurysm and intramural hematoma. The FET approach allows the replacement of the whole arch in one stage with the option of direct treatment of the proximal descending thoracic aorta based on the stent component, creating a safe landing zone for further endovascular treatment more distally. The remarkable feature of this technique is the possibility to perform more proximally (from zone 3 to zone 0) the distal anastomosis in to the arch. This allows for an easier distal anastomosis, reduced hypothermic circulatory arrest time and decreased risk of paraplegia (<5%). Early results are promising and according to the most recent series the rate of developing post-operative renal insufficiency ranges from 3 to 10%, the risk of stroke from 3% to 8% and mortality from 8–15%. The aim of the article will be to provide some knowledge about the use and application of FET procedures in different aortic situations.
doi:10.3390/medicina57101090 pmid:34684127 fatcat:jjuqdbhbmnb5nnidazircin3zq

Imaging of microwave field distribution over a non-fed gold pattern by using NV centers in diamond [article]

Giacomo Mariani, Shuhei Nomoto, Satoshi Kashiwaya, Shintaro Nomura
2018 arXiv   pre-print
Nitrogen-vacancy (NV) centers in diamond have been widely used as platforms for quantum information, magnetometry and imaging of microwave (MW) fields. High-precision spatial control of the MW field necessary to drive the electronic spin of NV centers is essential for these applications. Here, we report a controlled MW field distribution by excitation of a micrometer-scale gold pattern in vicinity of the diamond surface. The gold pattern excited by a planar ring MW antenna, acts as a receiving
more » ... ntenna and redistribute the MW field in a localized area, without a direct feed of electrical current. The planar ring MW antenna is designed to generate a uniform MW field on diamond substrate in an area of 0.785 mm^2, providing a useful tool for detecting the MW variations. We performed the imaging of the localized MW intensity on the micrometer-scale gold pattern by direct observation of electron spin Rabi oscillations, showing also the potential application of NV centers for imaging MW field and characterization of MW devices. We achieved an enhancement of about 19 times for the Rabi frequency on a scale of few micrometers for the gold pattern, compared to the bulk Rabi frequency in presence of the single planar ring MW antenna. Compared to previous methods, our method has been shown as a fast and easy tool for the spatial control of MW fields and spin manipulation of NV centers in diamond.
arXiv:1812.02864v1 fatcat:ovqpg66hqrhjjhho22yd3jj6xm

Total aortic arch replacement with frozen elephant trunk (Thoraflex)

Luca Di Marco, Davide Pacini, Giacomo Murana, Carlo Mariani, Ciro Amodio, Roberto Di Bartolomeo
2018 Annals of Cardiothoracic Surgery  
Figure 3 Postoperative CT angiogram showing normal morphology of the Thoraflex hybrid prosthesis and of the supraaortic trunks reimplantation.
doi:10.21037/acs.2018.04.05 pmid:30155427 pmcid:PMC6094015 fatcat:zulb6ofiq5hbvoc5qgamla7eqm

New tools in minimal invasive aortic valve surgery: case report

Sofia Martin-Suarez, Carlo Mariani, Giacomo Murana, Marianna Berardi, Marta Agulli, Savini Carlo, Davide Pacini
2021 Journal of Visualized Surgery  
Minimal invasive aortic valve replacement (MI-AVR) is turning a routine surgical procedure, but still, many surgeons are reluctant because of perception of some technical difficulties like the annular suture placement and the legature. We present the surgical case of a MI-AVR by using novel suturing and knotting device that could facilitate surgery and diminish technical difficulties. This is the case of a 65 years old female patient with a pathologic bicuspid aortic valve, with stenosis and
more » ... valent regurgitation. The patient was symptomatic for dyspnea (NYHA Class II) and referred to surgery for AVR, and after obtaining informed consent, we performed MI-AVR through upper hemisternotomy (UHS) by using two new surgical devices, particularly designed for minimal invasive surgery. The first device is composed by two handpieces: one is known as RAM ® , and it allows the passage of the suture, with the pledget in the ventricular side, through the native aortic valve anulus after the cusps have been removed and decalcification performed. Double "U" stitches are homogeneously and symmetrically placed. The second element, called SEW-EASY ® is used to pass equally the double needle suture through the sewing ring of the valvular prosthesis. To conclude, in this case we have also utilized a second device, a knotting one, known as COR-KNOT ® , giving rise to a quick and efficient suture ligature. Postoperative course was uneventful and the patient was on good conditions after 1 year of follow-up. The present case highlights the need and evolution of technology aimed to improve, simplify and increase safety in minimal invasive surgery.
doi:10.21037/jovs-20-126 fatcat:6sxuzh76jnb6hfg6smukoeyvaq

Cerebral perfusion issues in type A aortic dissection

Davide Pacini, Giacomo Murana, Luca Di Marco, Marianna Berardi, Carlo Mariani, Giuditta Coppola, Mariafrancesca Fiorentino, Alessandro Leone, Roberto Di Bartolomeo
2018 Journal of Visualized Surgery  
Stroke events are very common in acute type A aortic dissection. Cerebral malperfusion could manifest at presentation due to prolonged arch vessels hypoperfusion or develop after surgery for inadequate cerebral protection during arch repair. To reduce this detrimental complication there are several adjuncts that can be adopted for cerebral protection such as direct antegrade or retrograde cerebral perfusion (RCP) and use period of deep to moderate hypothermic circulatory arrest time; however,
more » ... ey are often insufficient as preoperative malperfusion already caused irreversible ischemic damages. The aim of the current review article is to analyze the principal series reporting on neurological injuries during type A aortic dissection to focus on the outcomes according to the type of surgical management and identify possible predictors to better manage this complication.
doi:10.21037/jovs.2018.03.20 pmid:29780723 pmcid:PMC5945856 fatcat:pb4vplgduvesfdr66kijits5ae

Hybrid conjugated polymer solar cells using patterned GaAs nanopillars

Giacomo Mariani, Ramesh B. Laghumavarapu, Bertrand Tremolet de Villers, Joshua Shapiro, Pradeep Senanayake, Andrew Lin, Benjamin J. Schwartz, Diana L. Huffaker
2010 Applied Physics Letters  
In this work, we study hybrid solar cells based on poly͑3-hexylthiophene͒-coated GaAs nanopillars grown on a patterned GaAs substrate using selective-area metal organic chemical vapor deposition. The hybrid solar cells show extremely low leakage currents ͑I Х 45 nA @Ϫ1V͒ under dark conditions and an open circuit voltage, short circuit current density, and fill factor of 0.2 V, 8.7 mA/ cm 2 , and 32%, respectively, giving a power conversion efficiency of = 0.6% under AM 1.5 G illumination.
more » ... e passivation of the GaAs results in further improvement, yielding = 1.44% under AM 1.5 G illumination. External quantum efficiency measurements of these polymer/inorganic solar cells are also presented. In the past few years polymer solar cells have gained attention due to their low cost, flexibility and ease of manufacturing. 1 Although conjugated polymers benefit from high absorption coefficients compared to inorganic semiconductors, low carrier mobilities ͑ϳ10 −4 cm 2 V −1 s −1 ͒ limit their energy conversion efficiency to less than 8%. 2 In contrast, inorganic solar cells have high carrier mobilities, enabling effective charge extraction and thus high quantum efficiencies. This suggests exciting possibilities for hybrid polymer/inorganic solar cells, which may be designed to simultaneously exploit the high carrier mobility from inorganic semiconductors and strong absorption coefficient from the polymer. Such a hybrid approach could effectively remove the carrier transport bottleneck suffered in conjugated polymers through the use of integrated III-V inorganic nanostructures. Much of the recent work in hybrid photovoltaics has aimed to augment the power conversion efficiency by embedding silicon nanocrystals, 3 or nanorods 4 and quantum dots 5 of II-VI inorganic semiconductors into a semiconducting polymer matrix. Surprisingly, relatively little work has been done involving hybrid solar cells with III-V inorganic nanostructures, despite the high efficiencies achieved in III-V bulk solar cells. The only report of a hybrid photovoltaic device involving III-V materials that we are aware of takes advantage of n-doped GaAs nanowires ͑via Au-catalyst growth͒ in combination with poly͑3-hexylthiophene͒ ͑P3HT͒ and has shown an energy conversion efficiency of 1.04%. 6
doi:10.1063/1.3459961 fatcat:oenqs5p5bzdyhkocf3mslym6em

Corruption in public projects and megaprojects: There is an elephant in the room!

Giorgio Locatelli, Giacomo Mariani, Tristano Sainati, Marco Greco
2017 International Journal of Project Management  
Despite the relevance of corruption in project selection, planning and delivery, the project management literature pays little attention to this crucial phenomenon. This paper sets the background to foster the discussion concerning how to select, plan and deliver infrastructure in corrupt project contexts. It presents the different types of corruptions and the characteristics of projects that are more likely to suffer from it. Corruption is particularly relevant for large and uncommon projects
more » ... here the public sector acts as client/owner or even as the main contractor. Megaprojects are "large unique projects" where public actors play a key role and are very likely to be affected by corruption. Corruption worsens both cost and time performance, and the benefits delivered. This paper leverages the institutional theory to introduce the concept of "corrupt project context" and, using the case study of the Italian high-speed railways, shows the impact of a corrupt context on megaprojects.
doi:10.1016/j.ijproman.2016.09.010 fatcat:zgce6mvnibf2lnnzig6f3xmre4
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