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Currently, surgeons in operating rooms are forced to focus their attention both on the patient's body and on flat low-quality surgical monitors, in order to get all the information needed to successfully complete surgeries. The way the data are displayed leads to disturbances of the surgeon's visuals, which may affect his performances, besides the fact that other members of the surgical team do not have proper visual tools able to aid him. The idea underlying this paper is to exploit mixed reality to support surgeons during surgical procedures. In particular, the proposed experimental setup, employed in the operating room, is based on an architecture that put together the Microsoft HoloLens, a Digital Imaging and Communications in Medicine (DICOM) player and a mixed reality visualization tool (i.e., Spectator View) developed by using the Mixed Reality Toolkit in Unity with Windows 10 SDK. The suggested approach enables visual information on the patient's body as well as information on the results of medical screenings to be visualized on the surgeon's headsets. Additionally, the architecture enables any data and details to be shared by the team members or by external users during surgical operations. The paper analyses in detail advantages and drawbacks that the surgeons have found when they wore the Microsoft HoloLens headset during all the ten open abdomen surgeries conducted at the IRCCS Hospital "Giovanni Paolo II" in the city of Bari (Italy). A survey based on Likert scale demonstrates how the use of the suggested tools can increase the execution speed by allowing multitasking procedures, i.e., by checking medical images at high resolution without leaving the operating table and the patient. On the other hand, the survey also reveals an increase in the physical stress and reduced comfort due to the weight of the Microsoft HoloLens device, along with drawbacks due to the battery autonomy. Additionally, the survey seems to encourage the use of DICOM Viewer and Spectator View both for surgical education and for improving surgery outcomes. Note that the real use of the conceived platform in the operating room represents a remarkable feature of this paper, since most if not all the studies conducted so far in literature exploit mixed reality only in simulated environments and not in real operating rooms. In conclusion, the study clearly highlights that, despite the challenges required in the forthcoming years to improve the current technology, mixed reality represents a promising technique that will soon enter the operating rooms to support surgeons during surgical procedures in many hospitals across the world. [ABSTRACT FROM AUTHOR]

A new low-voltage low-power class-AB second generation voltage conveyor (VCII) is presented. The proposed circuit is based on an improved class-AB flipped voltage follower (FVF) designed by adding a simple negative feedback loop to the conventional class-AB circuit. This modification ensures high current drive capability of at least 2 mA for both falling and rising edges of input signal along with very low 2- $\text{m}{\Omega }$ output impedance and high accuracy. Benefiting from the new class-AB FVF, the proposed VCII features a very simple implementation, extremely low impedance at $Y$ and $Z$ terminals (2 $\text{m}{\Omega }$), high impedance at $X$ terminal (370 $\text{k}{\Omega }$) and high accuracy in current and voltage conveying (99% and 98%, respectively). Moreover, it exhibits current drive capability 117.6 times larger than its bias current ($17~\mu \text{A}$). The circuit occupies $381.5\,\,\mu \text{m}\,\,\times 197\,\,\mu \text{m}$ area. The application of the proposed VCII as a voltage integrator is also presented. Simulation results using PSpice and 0.35- $\mu \text{m}$ CMOS technology with ±1.65-V supply voltage are provided to demonstrate the presented theory. A comparison with the literature is also provided. [ABSTRACT FROM AUTHOR]

Introduction. Uveal melanoma is the most common intraocular tumor in the adult population. It can affect any part of the uveal tract: the iris, ciliary body, and choroid. Historically, enucleation has been the mainstay of treatment for primary melanoma. In the last decade, however, radiotherapy has acquired an increasingly important role and has now become our first-line modality. However, it is still widely debated what is the most effective radiotherapy technique for this tumor. Purpose to perform a literature review on the utility of radiotherapy for primary ocular melanoma and determine the most effective radiotherapy technique. Materials and Methods. We included all systematic and narrative reviews on the topic, published between September 2007 and November 2017 on PubMed and SCOPUS. Two independent reviewers assessed the eligibility criteria for each article using the PRISMA checklist. The methodological quality of narrative and systematic reviews was evaluated with the INSA and AMSTAR checklists, respectively. Results. Our study analyzed a total of 23 studies, including 18 narrative reviews and 5 systematic reviews. Radiotherapy with Brachytherapy, Proton Therapy, SRS/SRT with gamma knife and cyber knife, are the most common choices for the treatment of primary ocular melanoma. These techniques allow for excellent lesion spread control, eye, and vision conservation, and improve overall patients' quality of life. Among the narrative reviews, the highest INSA score was 5/7, the lowest 2/7, the mean was 3.83/7 and median was 4/7. Among the systematic reviews, the highest AMSTAR score was 9/12, the lowest 4/12, the mean 5.6/7 and median 4/7. Conclusion. The number of studies available on this topic is scarce. Among those published, the methodological quality is modest, as assessed with the INSA and AMSTAR checklists. As a result, we are not able to determine what the most effective radiotherapy technique is. [ABSTRACT FROM AUTHOR]

This work deals with the design of a new readout electronics for silicon photomultipliers sensors. The so-called SiPMs sensors are an emerging technology currently diffusing in many applications and, among them, in the definition of a new generation of LIDAR systems. The latter, nowadays have a primary role in the evolution process that is involving Smart Cities, being an enabling technology in different fields. The solution here proposed is realized at electronic level with a 150 nm technology process from LFoundry and results provide a feasible demonstration of the capability of the proposed design approach to be employed in practical applications. [ABSTRACT FROM AUTHOR]

This brief presents a comprehensive study on a particular kind of conveyor called second-generation voltage conveyor (VCII). This building block is based on voltage conveying concept and is the dual of second generation current conveyor (CCII). It is shown that VCII is a very useful block in those configurations where CCII is limited, in terms of number of active blocks. The results of this brief are helpful in choosing the best building block between CCII and VCII for each specific application. Finally, for the first time, the CMOS implementation of VCII is also presented. Simulation results with PSPICE using 0.35- ${\mu }\text{m}$ CMOS technology and supply voltage of ±1.65 V are given to approve the theory. [ABSTRACT FROM AUTHOR]

Objective. This research represents a comparative study between metal-ceramic and zirconium-ceramic fixed prosthesis; it evaluates the maintenance of the prosthesis mechanical, functional and aesthetic characteristics few years after functional implantation. Methods. The study participants were 46 in total: 26 rehabilitated with a metal-ceramic fixed prosthesis and the remaining 20 with a zirconium-ceramic prosthesis. 13 male patients in the age range of 36-63 years and 13 female patients in the age range of 33-83 years (average age of 49.5 years) composed the metal-ceramic group. 11 male patients in the age range of 39-60 years and 9 female patients in the age range of 22-59 years (average age of 54.1 years) formed the zirconium-ceramic group. The study population only included patient with fixed prosthesis on three mandibular elements and absence of first inferior molar. The abutment teeth were both natural and vital or treated with endodontics: in any case, no periapical or periodontal lesions were present; at the beginning of the procedure, the patients displayed a healthy periodontium, no sign of bone reabsorption, stable occlusion and natural opposing dentition. Patients showing bruxism and poor oral hygiene were excluded from the study. All the participants gave their written informed consent. Results. The cases treated with metal-ceramic prosthesis resulted "excellent" in 57.14% of cases, "acceptable" in 39,16% of cases and only 3.70% "to remake". The results regarding the patient treated with zirconium-ceramic prosthesis during the entire follow-up period were "excellent" in 52.0% of cases, "acceptable" in 44.0% of cases, "to remake" in 4.0% of the cases. Conclusions. Our study demonstrates that none of the 28 metal-ceramic cases and none of the 25 zirconium-ceramic cases has been subject to substructure fractures. Both methods demonstrated a seven-year extremely high survival rate, with almost overlapping percentages of 96.3% for metal-ceramic and 96,0% for zirconium-ceramic. The confronted methods demonstrated to be adequate for the target rehabilitative therapy. The masticatory load is greatly tolerated by the respective substructures, which did not show any inclination to fracture. [ABSTRACT FROM AUTHOR]

In this paper, an integrable novel fully analog Wheatstone bridge-based interface for differential capacitance estimation is presented. Its working principle takes advantage of the modified De-Sauty AC bridge configuration being employed only by two capacitors and two resistors. A feedback loop controls one of the resistors (e.g. a voltage-controlled resistor), to obtain an evaluation of the differential capacitance variation on a full range, thanks to a general but very simple formula that considers both the 'auto-balancing' and the bridge 'out-of-equilibrium' ranges. The proposed interface shows a satisfactory accuracy, being the percentage relative error within 0.45% for the experimental results. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In the present study, we examined clinical and laser-evoked potentials (LEP) features in two groups of chronic tension-type headache (CTTH) patients treated with two different approaches: intra-oral appliance of prosthesis, aiming to reduce muscular tenderness, and 10 mg daily amitriptyline. Eighteen patients suffering from CTTH (IHS, 2004) participated in the study. We performed a basal evaluation of clinical features and LEPs in all patients (T0)vs.12 age- and sex-matched controls; successively, patients were randomly assigned to a two-month treatment by amitriptyline or intra-oral device appliance. The later LEPs, especially the P2 component, were significantly increased in amplitude in the CTTH group. Both the intra-oral prosthesis and amitriptyline significantly reduced headache frequency. Total Tenderness Score was significantly reduced in the group treated by the prosthesis. The amplitude of P2 response elicited by stimulation of pericranial zones showed a reduction after amitriptyline treatment. The results of this study may confirm that pericranial tenderness is primarily a phenomenon initiating a self-perpetuating circuit, favoured by central sensitisation at the level of the cortical nociceptive areas devoted to the attentive and emotive compounds of pain. Both the interventions at the peripheral and central levels may interrupt this reverberating circuit, improving the outcome of headache. [ABSTRACT FROM AUTHOR]