Coherent Control of Stimulated Emission Inside one Dimensional Photonic Crystals — Strong Coupling Regime

The present book chapter discusses the stimulated emission, in strong coupling regime, of an atom embedded inside a one dimensional (1D) Photonic Band Gap (PBG) cavity which is pumped by two counter-propagating laser beams. Quantum electrodynamics is applied to model the atom-field interaction, by considering the atom as a two level system, the e.m. field as a superposition of normal modes, the coupling in dipole approximation, and the equations of motion in Wigner-Weisskopf and rotating wave approximations. In addition, the Quasi Normal Mode (QNM) approach for an open cavity is adopted, interpreting the local density of states (LDOS) as the local density of probability to excite one QNM of the cavity; and therefore rendering this LDOS dependent on the phase difference of the two laser beams. In this book chapter we demonstrate that the strong coupling regime occurs at high values of the LDOS. In accordance with the results of the literature, the emission probability of the atom decays with an oscillatory behaviour, so that the atomic emission spectrum exhibits two peaks (Rabi splitting). The novelty of this book chapter is that the phase difference of the two laser beams can produce a coherent control of both the oscillations for the atomic emission probability and, as a consequence, of the Rabi splitting in the emission spectrum. Possible criteria to design active delay lines are finally discussed

Scientific Review on the Ionospheric Absorption and Research Prospects of a Complex Eikonal Model for One-Layer Ionosphere

The present paper conducts a scientific review on ionospheric absorption, extrapolating the research prospects of a complex eikonal model for one-layer ionosphere. As regards the scientific review, here a quasi-longitudinal (QL) approximation for nondeviative absorption is deduced which is more refined than the corresponding equation reported by Davies (1990). As regards the research prospects, a complex eikonal model for one-layer ionosphere is analyzed in depth here, already discussed by Settimi et al. (2013). A simple formula is deduced for a simplified problem. A flat, layered ionospheric medium is considered, without any horizontal gradient. The authors prove that the QL nondeviative amplitude absorption according to the complex eikonal model is more accurate than Rawer's theory (1976) in the range of middle critical frequencies

Training for MIS in pediatric urology: Proposition of a structured training curriculum

Abstract In Europe there are a lot of training centers for minimally invasive surgery (MIS) but a standardized MIS training program in pediatric urology doesn't exist at the moment. We performed a literature review with the last goals to propose a structured training curriculum in MIS urology for pediatric surgeons. Pediatric urologists have to obtain a valid MIS training curriculum completing the following 4 steps: (I) Theoretical part (theoretical courses, masterclass) to acquire theoretical knowledge; (II) experimental training (simulation on pelvic trainer, virtual reality simulators, animal models, 3-D ex-vivo models) to acquire basic laparoscopic skills; (III) stages in European centers of reference for pediatric MIS urology to learn all surgery aspects; (IV) personal operative experience. At the end of the training period, the trainee would be expected to perform several MIS urological procedures independently, under supervision of an expert tutor. At the end of the training program, each center will analyze the candidate training booklet and release for each applicant a certification after an exam. We think that this MIS training program in pediatric urology may assure an integrated acquisition of basic and advanced laparoscopic skills during residency training in pediatric urology. Each European country should adopt this program so as to secure a standardized technical qualification in MIS urology for all future pediatric urologists

Laparoscopic management of a newborn with a right Amyand's hernia and a left incarcerated inguinal hernia

A one month old boy presented with left incarcerated inguinal hernia. After unsuccessful manual reduction, we decided to perform laparoscopic herniorrhaphy. Laparoscopic examination showed a left hernia with intestinal loops that entered into the internal inguinal ring, on the right side there was an unknown patency of the peritoneal vaginal duct with the appendix completely incarcerated within the sac. On the left side, the loops were reduced with a combined technique of external manual pressure and internal pulling by forceps; the bowel was inspected, and the hernia was repaired. On the right side, the appendix was strongly adherent with the peritoneal vaginal duct, and the reduction was not possible. The appendix was dissected from the sac using a 3-mm monopolar hook and than reduced into the abdomen, then right herniorrhaphy was performed. Two days after surgery, the baby had fever and abdominal distension. He was re-operated through mini-Pfannenstiel incision and an ischemic appendix was identified and removed. Postoperative period was uneventful. In our case, laparoscopy allowed for simultaneous reduction under direct visual control, inspection of the incarcerated organ, definitive repair and incidentally discovery and treatment of the contralateral incarcerated Amyand′s hernia. In case of incarcerated appendix, appendectomy is preferable during the same procedure to reduce the incidence of postoperative complications

Motion primitive based random planning for loco-manipulation tasks

Several advanced control laws are available for complex robotic systems such as humanoid robots and mobile manipulators. Controls are usually developed for locomotion or for manipulation purposes. Resulting motions are usually executed sequentially and the potentiality of the robotic platform is not fully exploited. In this work we consider the problem of loco-manipulation planning for a robot with given parametrized control laws known as primitives. Such primitives, may have not been designed to be executed simultaneously and by composing them instability may easily arise. With the proposed approach, primitives combination that guarantee stability of the system are obtained resulting in complex whole-body behavior. A formal definition of motion primitives is provided and a random sampling approach on a manifold with limited dimension is investigated. Probabilistic completeness and asymptotic optimality are also proved. The proposed approach is tested both on a mobile manipulator and on the humanoid robot Walk-Man, performing loco-manipulation tasks

A method to test HF ray tracing algorithm in the ionosphere by means of the virtual time delay

It is well known that a 3D ray tracing algorithm furnishes the ray's coordinates, the three components of the wave vector and the calculated group time delay of the wave along the path. The latter quantity can be compared with the measured group time delay to check the performance of the algorithm. Simulating a perfect reflector at an altitude equal to the virtual height of reflection, the virtual time delay is assumed as a real time delay. For a monotonic electronic density profile we find a very small relative difference between the calculated and the virtual delay for both analytic and numerical 3D electronic density models.Comment: 17 pages, 8 figure

Corrigendum: The Walk-Man Robot Software Architecture

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Pyeloplasty techniques using minimally invasive surgery (MIS) in pediatric patients

Abstract Hydronephrosis is the most common presentation of ureteropelvic junction (UPJ) obstruction. We reviewed literature, collecting data from Medline, to evaluate the current status of minimally invasive surgery (MIS) approach to pyeloplasty. Since the first pyeloplasty was described in 1939, several techniques has been applied to correct UPJ obstruction, but Anderson-Hynes dismembered pyeloplasty is established as the gold standard, to date also in MIS technique. According to literature several studies underline the safety and effectiveness of this approach for both trans- and retro-peritoneal routes, with a success rate between 81-100% and an operative time between 90-228 min. These studies have demonstrated the safety and efficacy of this procedure in the management of UPJ obstruction in children. Whether better the transperitoneal, than the retroperitoneal approach is still debated. A long learning curve is needed especially in suturing and knotting

Laparoscopic extravesical ureteral reimplantation (LEVUR): A systematic review

Abstract BACKGROUND: Laparoscopic ureteral reimplantation is a feasible method for treating ureteral pathology with good preliminary results in the literature. In this study, we review medium term results for laparoscopic ureteral reimplantation and discuss current developments of this procedure. METHODS: Medline and Embase databases were searched using relevant key terms to identify reports of paediatric laparoscopic extravesical ureteral reimplantation (LEVUR). Literature reviews, case reports, series of 20 years) were excluded. RESULTS: Five studies were assessed, overall, 69 LEVUR were performed in children. Despite different surgical technique, in all case the technique was respected. Patient demographics, preoperative symptoms, radiological imaging, complications, and postoperative outcomes were analyzed. Median success rate was 96%. Complications were reported in five cases. CONCLUSIONS: This study is limited by the data given in the individual series: varied criteria used for patient selection and outcome as well as inconsistent pre- and post-operative imaging data precluded a meta-analysis. But it demonstrates that the laparoscopic ureteral reimplantation is an effective procedure with good medium-term results. We believe that in well selected patients this procedure will become an established treatment option