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The integration of fast and power efficient electro-absorption modulators on silicon is of utmost importance for a wide range of applications. To date, Franz-Keldysh modulators formed of bulk Ge or GeSi have been widely adopted due to the simplicity of integration required by the modulation scheme. Nevertheless, to obtain operation for a wider range of wavelengths (O to C band) a thick stack of Ge/GeSi layers forming quantum wells is required, leading to a dramatic increase in the complexity linked to sub-micron waveguide coupling. In this work, we present a proof-of-concept integration between micro-metric waveguides, through the butt-coupling of a [Formula: see text] thick N-rich silicon nitride (SiN) waveguide with a [Formula: see text] thick silicon waveguide for O-band operation. A numerical analysis is conducted for the design of the waveguide-to-waveguide interface, with the aim to minimize the power coupling loss and back-reflection levels. The theoretical results are compared to the measured data, demonstrating a coupling loss level of [Formula: see text] for TE and TM polarisation. Based on the SiN-SOI interconnection simulation strategy, the simulation results of a quantum-confined Stark effect (QCSE) stack waveguide coupled to a SiN waveguide are then presented., (© 2022. The Author(s).)

In this review we present some of the recent advances in the field of silicon nitride photonic integrated circuits. The review focuses on the material deposition techniques currently available, illustrating the capabilities of each technique. The review then expands on the functionalisation of the platform to achieve nonlinear processing, optical modulation, nonvolatile optical memories and integration with III-V materials to obtain lasing or gain capabilities.

Background and Objectives : recent studies suggest an implication of immune mechanisms in atherosclerotic disease. In this paper, the interaction between inflammation, calcification, and atherosclerosis on the vessel walls of patients with chronic kidney disease (CKD) is described and evaluated. Materials and Methods : patients with stage V CKD, either on pre-dialysis (group A) or on hemodialysis (HD) for at least 2 years (group B), in whom a radiocephalic arteriovenous fistula (RCAVF) was created, were included in the study. The control group included healthy volunteers who received radial artery surgery after an accident. The expressions of inflammatory cells, myofibroblasts, and vascular calcification regulators on the vascular wall were estimated, and, moreover, morphometric analysis was performed. Results : the expressions of CD68(+) cells, matrix carboxyglutamic acid proteins (MGPs), the receptor activator of nuclear factor-kB (RANK) and RANK ligand (RANKL), and osteoprotegerin (OPG), were significantly increased in CKD patients compared to the controls p = 0.02; p = 0.006; p = 0.01; and p = 0.006, respectively. In morphometric analysis, the I/M and L/I ratios had significant differences between CKD patients and the controls 0.3534 ± 0.20 vs. 0.1520 ± 0.865, p = 0.003, and 2.1709 ± 1.568 vs. 4.9958 ± 3.2975, p = 0.03, respectively. The independent variables correlated with the degree of vascular calcification were the intensity of CD34(+), aSMA(+) cells, and OPG, R 2 = 0.76, p < 0.0001, and, with intima-media thickness (IMT), the severity of RANKL expression R 2 = 0.3, p < 0.0001. Conclusion : atherosclerosis and vascular calcification in CKD seem to be strongly regulated by an immunological and inflammatory activation on the vascular wall.

Pyomyositis is an uncommon primary bacterial infection of skeletal muscles, usually caused by Staphylococcus aureus. Predisposing factors for pyomyositis include immunodeficiency, trauma, injection drug use, concurrent infection and malnutrition. The diagnosis, staging of the disease and differential diagnosis are established by ultrasound, CT and MRI. Treatment involves surgical drainage and antibiotic therapy. We report a case of abdominal rectus muscle pyomyositis, which constitutes, as far as we know, the second reported in bibliography, while Prevotella disiens is firstly reported as causative agent., Competing Interests: Conflict of interest: the authors declare no potential conflict of interest.

Background: Fournier's gangrene (FG) is a rapidly evolving necrotizing fasciitis of the perineum and the genital area, the scrotum as it most commonly affects man in the vast majority of cases. It is polymicrobial in origin, due to the synergistic action of anaerobes and aerobes and has a very high mortality. There are many predisposing factors including diabetes mellitus, alcoholism, immunosuppression, renal, and hepatic disease. The prognosis of the disease depends on a lot of factors including but not limited to patient age, disease extent, and comorbidities. The purpose of the study is to describe the experience of a general surgery department in the management of FG, to present the multimodal and multidisciplinary treatment of the disease, to identify predictors of mortality, and to make general surgeons familiar with the disease., Methods: The current retrospective study is presenting the experience of our general surgery department in the management of FG during the last 20 years. The clinical presentation and demographics of the patients were recorded. Also we recorded the laboratory data, the comorbidities, the etiology, and microbiology and the therapeutic interventions performed, and we calculated the various severity indexes. Patients were divided to survivors and non-survivors, and all the collected data were statistically analyzed to assess mortality factors using univariate and then multivariate analysis., Results: In our series, we treated a total of 24 patients with a mean age 58.9 years including 20 males (83.4%) and 4 females (16.6%). In most patients, a delay between disease onset and seeking of medical help was noted. Comorbidities were present in almost all patients (87.5%). All patients were submitted to extensive surgical debridements and received broad-spectrum antibiotics until microbiological culture results were received. Regarding all the collected data, there was no statistically significant difference between survivors and non-survivors except the presence of malignancy in non-survivors ( p  = 0.036) and the lower hemoglobin ( p  < 0.001) and hematocrit ( p  = 0.002) in non-survivors. However, multivariate analysis did not reveal any predictor of mortality., Conclusion: Early diagnosis, aggressive thorough surgical treatment, and administration of the proper antibiotic treatment comprise the cornerstone for the outcome of this disease. In small populations like in the present study, it is difficult to recognize any predictors of mortality and even the severity indexes, which take into account a lot of data cannot predict mortality.

Malposition of a central venous hemodialysis catheter, mainly due to central vein stenosis or thrombosis, is not an uncommon complication. Herein, we present a rare cause of a left external jugular vein hemodialysis catheter, malpositioned into the ipsilateral internal jugular-subclavian venous route, due to a stenosed stent that has been placed into the ipsilateral brachiocephalic vein.

This report describes a case of a mycotic aneurysm of the infrarenal abdominal aorta infected by Vibrio mimicus, which is the only such case ever reported in the literature. The 80-year-old male patient was first treated for gastroenteritis for 7 days. Two months later, he was admitted to the hospital and the aneurysm was diagnosed by three-dimensional computed tomography. The aneurysm was excised and the restoration was done using a 16-mm Dacron straight graft. The cultivation of the excised aneurysm and the inflammatory fluid was positive for V. mimicus. The postoperative period was free of complications and the patient has remained asymptomatic during the 4-year follow-up.

Permanent central catheter for hemodialysis was inserted via external jugular vein in 95 patients. In all the cases the catheter blood flow was more than 250 ml/min. There were no severe complications. The procedure of insertion of permanent catheter for hemodialysis via the external jugular vein is described. It is concluded that the insertion of permanent catheter for hemodialysis via the external jugular vein is a simple and short-time procedure without any severe complications.

When the superficial arm veins are not suitable for the creation of a conventional endogenous arteriovenous (A-V) fistula or the placement of a prosthetic graft in the forearm, the use of the deep forearm veins as an outflow system to construct an A-V graft access seems to be a reasonable alternative. Using this approach, we placed 6 prosthetic grafts in 6 hemodialysis patients in whom conventional methods had failed. Adequate functioning of this 'deep vein'-type vascular access in these 6 patients has been maintained for 3, 6, 11, 15, 19 and 24 months, respectively, without complications or any need for further interventions. Only one graft failed after 6 months. Our preliminary results indicate that this technique can be used successfully when the superficial forearm veins have been exhausted, thus avoiding the use of upper-arm or axillary veins., (Copyright 2000 S. Karger AG, Basel)