Biperiodic nanostructured waveguides for wavelength-selectivity of hybrid photonic devices.

A biperiodic nanostructuration consisting of a super-periodicity added to a nanohole lattice of subwavelength pitch is demonstrated to provide both modal confinement and wavelength selectivity within a hybrid III-V on a silicon waveguide. The wavelength-selective behavior stems from finely tuned larger holes. Such biperiodic hybrid waveguides have been fabricated by oxide-free bonding III-V material on silicon and display well-defined stop bands. Such nanostructured waveguides offer the versatility for designing advanced optical functions within hybrid devices. Moreover, keeping the silicon waveguide surface planar, such nanostructured waveguides are compatible with electrical operation across the oxide-free hybrid interface.

Electroabsorption and refractive index modulation induced by intersubband transitions in GaN/AlN multiple quantum wells.

The aim of the present paper was to determine the index variation in the GaN/AlN heterostructures related to the population/depletion of the quantum well fundamental state leading to the absorption variation in the spectral domain around 1.5 µm. The variation of the refractive index was deduced from the shift of the position of the beating interference maxima of different order modes in a guided wave configuration. The obtained index variation with bias from complete depletion to full population of the quantum wells is around -5 × 10(-3). This value is similar to the typical index variation achieved in InP and is an order of magnitude higher than the index variation obtained in silicon.

Metal-dielectric metamaterials for guided wave silicon photonics.

The aim of the present paper is to investigate the potential of metallic metamaterials for building optical functions in guided wave optics at 1.5 µm. A significant part of this work is focused on the optimization of the refractive index variation associated with localized plasmon resonances. The minimization of metal related losses is specifically addressed as well as the engineering of the resonance frequency of the localized plasmons. Our numerical modeling results show that a periodic chain of gold cut wires placed on the top of a 100 nm silicon waveguide makes it possible to achieve a significant index variation in the vicinity of the metamaterial resonance and serve as building blocks for implementing optical functions. The considered solutions are compatible with current nano-fabrication technologies.

Efficient control of a 3D optical mode using a thin sheet of transformation optical medium.

We report on a mode adapter that transitions light between two SOI waveguides having different widths. The device has been designed using a two-dimensional embedded coordinate transformation and consists of a thin sheet of a controlled anisotropic material directly placed on top of the Si slab. We demonstrate that this layer effectively controls the flow of energy propagating in the Si slab by performing three-dimensional full-wave simulations. The proposed geometry can be implemented with planar optical metamaterials for various applications in guided optics.

The pattern of paediatric blast injury in Afghanistan.

INTRODUCTION: Between 2009 and 2015, 3746 children died, and 7904 were injured as a result of armed conflict within Afghanistan. Improvised explosive devices (IEDs) and explosive remnants of war accounted for 29% of child casualties in 2015. The aim of this study was to review the burden of paediatric blast injuries admitted to Camp Bastion, Afghanistan, and to investigate the hypothesis that children suffer proportionally more head injuries than adults. METHOD: A retrospective analysis was undertaken of prospectively collected data derived from the UK Joint Theatre Trauma Registry of ambulant paediatric (aged 2-15 years) admissions with blast injuries at the Role 3 Field Hospital, Camp Bastion from June 2006 to March 2013. The data set included demographic information, injury profile and severity (New Injury Severity Score) and operative findings. The pattern of injuries were investigated by looking at trends in the number and severity of injuries sustained by each body region. RESULTS: During this period, 295 admissions were identified, 76% of whom were male, with an overall mortality rate of 18.5%. The most common blast mechanism was an IED (68%) causing 80% of fatalities. The lower extremities were the most commonly injured body region, accounting for 31% of total injuries and occurring in 62% of cases. 24.3% of children between 2 and 7 years suffered severe head or neck injuries compared with 19.8% of children aged between 8 and 15 years. 34% of head injuries were rated unsurvivable and accounted for 88% of fatalities. 77% of cases required an operation with a mean operating time of 125 min. The most common first operations were debridement of soft tissues (50%), laparotomy (16%) and lower limb amputation (11%). CONCLUSION: Although paediatric blast casualties represented a small percentage of the overall workload at Camp Bastion Role 3 Medical Facility, the pattern of injuries seen suggests that children are more likely to sustain severe head, face and neck injuries than adults.

Experimental evidence for superprism phenomena in SOI photonic crystals.

A first experimental demonstration of a planar superprism in silicon microphotonics technology using silicon on insulator (SOI) substrates is presented. Experimental results for anomalous wavelengthdependent angular dispersion in SOI triangular lattice planar photonic crystals are reported. An angular swing of 14 degrees is measured for light propagating near the Gamma-K direction as the input wavelength is changed from 1295 nm to 1330 nm, which corresponds to an angular dispersion of 0.4 degrees /nm. For the Gamma-M direction, a negative wavelength dispersion has been recorded. An opposite sign angular deviation of 21 degrees is observed as the input wavelength is changed from 1316 nm to 1332 nm, i.e. a dispersion of 1.3 degrees /nm.

Methylcholanthrene-induced tumors in resistant and sensitive Jensen sarcoma rats. i. effect of fresh prepared MC emulsion.

By two subcutaneous or intramuscular injections of 20-methylcholanthrene (MC), 5 mg/animal in vegetal oil, followed after 74 days by 10 mg of MC emulsion, sarcomata were obtained in 63.6% of Jensen sarcoma-resistant rats (R) and in 36.8% of Jensen sarcoma-sensitive rats (S). One of the induces sarcomas, transplanted from R to R and then to S rats, presented a very high antigenicity: it strongly immunised receptive rats against the induced sarcoma and also, in a lower degree, against the Jensen sarcoma. Antigenicity was maintained up to the tenth passage.

Carcinoma of deep male urethra.

Carcinoma of the deep male urethra is a rare disease. Conservative measures yielding dismal outcomes were standard until 1957, with the report of an 80 per cent five-year survival rate after radical surgery. To assess the value of this surgery, we reviewed all cases of carcinoma of the deep male urethra managed at UCLA Medical Center and its affiliated hospitals between 1952 and 1980. Of the patients managed with radical surgery, 1 died of a myocardial infarction between staged surgical procedures, and 5 died of their disease between twelve and fifty-two months postoperatively (mean survival, 26 months). There were 2 long-term disease-free survivors, yielding a survival rate of 25 per cent. We have also compiled the results of all major series dealing with deep urethral carcinoma published subsequent to the 1957 report. This review of the literature supports the concept that radical extirpative surgery is mandatory in the management of carcinoma of the deep male urethra.

Cutaneous and subcutaneous metastases from carcinoma of prostate.

Secondary cutaneous and subcutaneous metastases originating from a visceral carcinoma are relatively uncommon and are associated most frequently with mammary, pulmonary, renal, and colonic cancers. Cutaneous and subcutaneous deposits from cancer of the prostate must be classified as extremely rare, e.g., only one solitary cutaneous metastatic carcinoma of prostatic origin was seen among 136,017 surgical and postmortem specimens submitted to the department of pathology at UCLA Hospital from male patient thirty-five years of age and older during the years between 1955 and 1980. Recently we observed a second case. A discussion of these 2 cases and a review of the English literature are reported.

Laser ablation of renal pelvic transitional cell carcinoma in a solitary kidney: a 9-year follow-up.

Neodymium:yttrium-aluminum-garnet (Nd:YAG) laser ablation of upper-tract urothelial tumors has been well documented in the urologic literature. However, the standard treatment of choice remains radical nephroureterectomy with excision of a cuff of the bladder for most patients. We report on a patient with recurrent superficial transitional cell carcinoma of the renal pelvis in a solitary kidney treated with Nd:YAG laser with a 9-year follow-up.

Management of adenocarcinoma of prostate with diethylstilbestrol diphosphate and cyclophosphamide.

Eleven patients with terminal metastatic prostatic carcinoma were selected for a pilot study to evaluate how effective diethylstilbestrol diphosphate (Stilphostrol) and cylcophosphamide (Cytoxan) are in this disease. Six of 7 patients had a good response when treated with diethylstilbestrol diphosphate. The mean duration of response was 6.4 months. All 6 patients given cyclophosphamide had marked relief of pain and increased mobility. Of these, 3 died twelve, sixteen, and nineteen weeks, respectively, following initiation of therapy while still benefiting from pain relief. The mean duration of response was 14.8 weeks.

Renal malakoplakia: acute onset of renal failure due to bilateral upper tract involvement.

A case of malakoplakia-induced acute renal failure is presented. In the twenty months following diagnosis the patient remains anuric. Malakoplakia involving the upper urinary tract is not self-limiting and should be considered in the differential diagnosis of acute renal failure.

Spontaneous rupture of ureter.

A patient with spontaneous ureteral rupture in the absence of obstruction or calculus disease is presented. In addition to ureteral rupture this patient also had a penile squamous cell carcinoma and infected inguinal lymph nodes. A review of the literature discloses that all reported cases with spontaneous rupture of the ureter had an underlying process leading to that rupture. It is considered, therefore, that rupture of the ureter should be designated as "traumatic" or "nontraumatic." The term "spontaneous," implying a primary event, is a misnomer. No such case has been reported occurring in an otherwise healthy individual.

Treatment of ureteral calculi by extracorporeal shock-wave lithotripsy. UCLA experience.

One hundred sixteen patients underwent extracorporeal shock-wave lithotripsy (ESWL) for ureteral stones. In 108 patients, the stones were manipulated pre-ESWL whereas 8 patients underwent ESWL without prior stone manipulation. Ureteral lubrication using a 2% Xylocaine jelly solution greatly facilitated the retrograde advancement of the calculus or the passage of ureteral catheters alongside the stone. ESWL disintegrated all but 4 stones for an overall success rate of 96.6 per cent. It is considered that the combination of retrograde ureteral stone repositioning and ESWL is a highly successful alternative in the management of ureteral calculi.

Urethral gap in complete disruption of membranous urethra.

In patients with complete disruption of the membranous urethra treated initially with placement of a suprapubic cystostomy, delayed synchronous retrograde and voiding cystourethrograms failed to demonstrate accurately the distance between the two urethral ends. Radiographic exposure obtained during synchronous instrumentation of the anterior and posterior urethra in the anesthetized patient was the most precise method of defining the extent of the urethral gap. Any surgical decision should be based on this type of investigation. In most cases of pelvic crush injuries, the severed membranous urethra probably remains attached in close proximity to the distal segment, thus directing the redescent of the prostate and bladder base in the presence of a contracting pelvic hematoma.

Statistical characteristics of radionuclide concentration field around a nuclear power plant.

A Markov chain model with two states is used for investigating the space and time structure of the concentration field around an elevated continuous source. The concentration field is computed with a time-dependent Gaussian puff dispersion model run with observed meteorological data as input. Spatial distributions of transition probability, Besson persistence coefficient and order of Markov chain are presented for tritium routinely released from a nuclear power plant located about 100 miles east of Bucharest, Romania.

TNFα inhibitor induced lupus-like syndrome (TAILS) in a patient with IBD.

BACKGROUND: In patients with autoimmune diseases like inflammatory bowel diseases there has been reported a drug-induced lupus like syndrome secondary to TNFα inhibitors. OBJECTIVE: clinical case presentation and literature review of patients who develop lupus-like syndrome in relation to TNFα antagonists and their future therapeutic options. MATERIALS AND METHODS: we report the case of a 27-year old woman with colonic Crohn's disease on combo-therapy (infliximab+azathioprine) for nearly two years who developed peripheral arthritis and malar rash in the context of TAILS. RESULTS: our patient had positive anti-nuclear antibody, arthritis, malar rash, anemia and leukopenia. Her symptomes remited after discontinuation of infliximab and subsequently she started adalimumab for her Crohn's colitis; more than a year after switching between TNFα inhibitor molecules and stopping azathioprine she is feeling very well. TAILS is a rare condition described in the literature that can affect 0.5-1% of individuals, more often in association with etanercept and infliximab. Several pathogenic routes have been incriminated in the apparition of this syndrome there is still no definite mechanism up to date. Management options include discontinuation of the drug, corticosteroids, hydroxycloroquine sulfate and switching for other immunosupressives. CONCLUSIONS: TAILS can appear even a long time after first exposure to TNFα antagonists. In our case, the association with azathioprine was not a primary prophylactic solution.

Lessons learned from the first 50 thyroidectomies with Harmonic Focus Curved Shears - technical note.

Precise and safe hemostasis is necessary for successful thyroid surgery. In this respect, the advent of the ultrasonic surgical device Harmonic Focus Curved Shears (HFCS) from Ethicon Endo-Surgery constituted a major progress in the domain by its multiple capabilities of dissection, grasping, vessel sealing and transecting. The paper presents the initial experience of 50 cases with this device of a surgical team with special interest in endocrine surgery, mostly thyroid and parathyroid. The thyroid conditions for which surgery was indicated were: diffuse toxic goiter in 8 patients; multinodular toxic and nontoxic goiter in 30 patients; autonomous nodule in 2 patients; 2 patients with benign nodules at fine needle aspiration biopsy (FNAB); 4 patients with nodules positive for carcinoma at FNAB, among them 2 with unilateral cervical lymph nodes enlargement; 4 patients with highly suspect nodule on FNAB. The types of surgery performed were 4 hemithyroidectomies and 46 total thyroidectomies, 2 in association with unilateral functional neck dissections. We had 4 intraoperative hemorrhagic incidents, all in the first 15 cases and imputable to lack of expertise and improper usage of the device. We registered the following noticeable postoperative complications: 1 cervical hematoma from an arteriolar source in sternothyroid muscle demanding prompt reintervention; 8 hypocalcemias and 2 vocal cord paresis, none of which permanent. We remarked several advantages with HFCS: no necessity of changing instruments, fluentness of the intervention and more comfort for the operating team, reduced operating time, safe hemostasis. Some important tips and tricks with the usage of the instrument are presented.

Hepatocellular carcinoma among cirrhotics--utility of screening and surveillance programs--review article.

Screening of known cirrhotics for hepatocellular cancer (HCC) has long been a contentious topic. Studies to date have failed to conclusively prove or disprove the validity of α-fetoprotein (AFP) and hepatic ultrasound as screening mechanisms for HCC among cirrhotics. It is not clear whether these screening mechanisms provide any benefit in terms of reduced morbidity and mortality. Screening for HCC among cirrhotics by using AFP and/or imaging at every 6 months correlate with HCC diagnosis, thus portending better treatment options and an improved prognosis. Screening all the known cirrhotics for HCC may lead to decreased mortality.

In vitro toxicity evaluation of Ti(4+)-stabilized γ-Bi2O3 sillenites.

We report results regarding the in vitro toxicology of γ-Bi2O3 represented by its isomorphous phase Bi12TiO20 (γ-BTO). The γ-BTO microparticles were synthesized by two methods: coprecipitation from a bismuth nitrate-tetrabutyl titanate solution and solid state reaction of Bi2O3 and TiO2 oxides. The structural and morphological characteristics of the obtained materials were determined using X-ray diffraction (XRD), selected area electron diffraction (SAED), transmission (TEM) and scanning (SEM) electron microscopy. The elemental composition was investigated using energy dispersive spectrometry (EDS). The cytotoxicity and oxidative/nitrosative stress (intracellular reactive oxygen species (ROS) and nitric oxide (NO) release) induced by the studied microparticles in HepG2, SH-SY5Y and 3T3-L1 cell cultures were determined using the MTT, DCF-DA (2',7'-dichlorfluorescein-diacetate) and Griess methods respectively. Depending on the cell type and γ-BTO concentration, results showed only weak cytotoxic effects after 24h of γ-BTO exposure and cell proliferation effects for longer treatment times. Only reduced NO release increases (corresponding to high γ-BTO concentrations) were detected in case of SH-SY5Y and 3T3-L1 cells. The intracellular ROS production (higher for HepG2 cells) appeared inversely proportional to the γ-BTO concentration. The obtained results indicated a promising in vitro biocompatibility of γ-BTO and encourage further studies regarding its potential for biomedical applications.