An ultra high-endurance memristor using back-end-of-line amorphous SiC.

Integrating resistive memory or neuromorphic memristors into mainstream silicon technology can be substantially facilitated if the memories are built in the back-end-of-line (BEOL) and stacked directly above the logic circuitries. Here we report a promising memristor employing a plasma-enhanced chemical vapour deposition (PECVD) bilayer of amorphous SiC/Si as device layer and Cu as an active electrode. Its endurance exceeds one billion cycles with an ON/OFF ratio of ca. two orders of magnitude. Resistance drift is observed in the first 200 million cycles, after which the devices settle with a coefficient of variation of ca. 10% for both the low and high resistance states. Ohmic conduction in the low resistance state is attributed to the formation of Cu conductive filaments inside the bilayer structure, where the nanoscale grain boundaries in the Si layer provide the pre-defined pathway for Cu ion migration. Rupture of the conductive filament leads to current conduction dominated by reverse bias Schottky emission. Multistate switching is achieved by precisely controlling the pulse conditions for potential neuromorphic computing applications. The PECVD deposition method employed here has been frequently used to deposit typical BEOL SiOC low-k interlayer dielectrics. This makes it a unique memristor system with great potential for integration.

Terbinafine and risperidone drug interaction contributing to clinical changes in a forensic psychiatric patient.

Risperidone is a second generation "atypical" antipsychotic that exhibits its clinical effects through a combined effort of risperidone and its active metabolite, 9-hydroxyrisperidone (9-OHR), otherwise known as paliperidone. Risperidone is hepatically metabolized by the cytochrome P450 2D6 (CYP2D6) enzyme into 9-OHR. Significant interference with the metabolism of risperidone may lead to clinical consequences for patients via alterations in the ratio of the parent compound and active metabolite. This patient case reports 1 example of how a drug interaction could contribute to delayed response to a medication increase after psychiatric decompensation. A forensic psychiatric patient was transitioned from oral risperidone to risperidone microspheres long-acting injectable and had worsening of symptoms, necessitating an increased dose of the injection. This increase in symptoms may have been prolonged by addition of a CYP2D6 inhibitor, terbinafine. The changes in clinical symptoms correlate with medication concentrations that were drawn before terbinafine was started, during terbinafine therapy, and after terbinafine was discontinued.

Mid-infrared silicon-on-insulator waveguides with single-mode propagation over an octave of frequency.

Increasing the working optical bandwidth of a photonic circuit is important for many applications, in particular chemical sensing at mid-infrared wavelengths. This useful bandwidth is not only limited by the transparency range of waveguide materials, but also the range over which a waveguide is single or multimoded for predictable circuit behaviour. In this work, we show the first experimental demonstration of "endlessly single-mode" waveguiding in silicon photonics. Silicon-on-insulator waveguides were designed, fabricated and characterised at 1.95 µm and 3.80 µm. The waveguides were shown to support low-loss propagation (1.46 ± 0.13 dB/cm loss at 1.95 µm and 1.55 ± 0.35 dB/cm at 3.80 µm) and single-mode propagation was confirmed at 1.95 µm, meaning that only the fundamental mode was present over the wavelength range 1.95 - 3.80 µm. We also present the prospects for the use of these waveguides in sensing applications.

Broadband 2 × 2 multimode interference coupler for mid-infrared wavelengths.

Beam splitters are core components of photonic integrated circuits and are often implemented with multimode interference couplers. While these devices offer high performance, their operational bandwidth is still restrictive for sensing applications in the mid-infrared wavelength range. Here we experimentally demonstrate a subwavelength-structured 2×2 multimode interference coupler with high performance in the 3.1-3.7µm range, doubling the bandwidth of a conventional device.

Thick BaTiO3 Epitaxial Films Integrated on Si by RF Sputtering for Electro-Optic Modulators in Si Photonics.

Thick epitaxial BaTiO3 films ranging from 120 nm to 1 µm were grown by off-axis RF magnetron sputtering on SrTiO3-templated silicon-on-insulator (SOI) substrates for use in electro-optic applications, where such large thicknesses are necessary. The films are of high quality, rivaling those grown by molecular beam epitaxy (MBE) in crystalline quality, but can be grown 10 times faster. Extraction of lattice parameters from geometric phase analysis of atomic-resolution scanning transmission electron microscopy images revealed how the in-plane and out-of-plane lattice spacings of sputtered BaTiO3 changes as a function of layer position within a thick film. Our results indicate that compared to molecular beam epitaxy, sputtered films retain their out-of-plane polarization (c-axis) orientation for larger thicknesses. We also find an unusual re-transition from in-plane polarization (a-axis) to out-of-plane polarization (c-axis), along with an anomalous lattice expansion, near the surface. We also studied a method of achieving 100% a-axis-oriented films using a two-step process involving amorphous growth and recrystallization of a seed layer followed by normal high temperature growth. While this method is successful in achieving full a-axis orientation even at low thicknesses, the resulting film has a large number of voids and misoriented grains. Electro-optic measurement using a transmission setup of a sputtered BTO film grown using the optimized conditions yields an effective Pockels coefficient as high as 183 pm/V. A Mach-Zehnder modulator fabricated on such films exhibits phase shifting with an equivalent Pockels coefficient of 157 pm/V. These results demonstrate that sputtered BTO thick films can be used for integrated electro-optic modulators for Si photonics.

Solitary castrate-resistant prostate cancer metastasis to adrenal gland with concordant intense avidity on PSMA and FDG PET.

Isolated prostate cancer metastasis to the adrenal gland is rare. We report a case of concordant high uptake in a solitary adrenal metastasis on both prostate-specific membrane antigen and fluorodeoxyglucose positron-emission tomography in a patient with castrate-resistant prostate cancer. Good initial biochemical response was achieved with laparoscopic adrenalectomy. The patient developed lymph node recurrence 12 months later, although remains asymptomatic on hormonal treatment 22 months post-operatively, in keeping with prior results for metastasis-directed therapy which can delay time to additional treatment. Application of dual tracer PET can be valuable for prostate cancer staging and guidance of metastasis-directed treatment.

Nanoelectromechanical relay without pull-in instability for high-temperature non-volatile memory.

Emerging applications such as the Internet-of-Things and more-electric aircraft require electronics with integrated data storage that can operate in extreme temperatures with high energy efficiency. As transistor leakage current increases with temperature, nanoelectromechanical relays have emerged as a promising alternative. However, a reliable and scalable non-volatile relay that retains its state when powered off has not been demonstrated. Part of the challenge is electromechanical pull-in instability, causing the beam to snap in after traversing a section of the airgap. Here we demonstrate an electrostatically actuated nanoelectromechanical relay that eliminates electromechanical pull-in instability without restricting the dynamic range of motion. It has several advantages over conventional electrostatic relays, including low actuation voltages without extreme reduction in critical dimensions and near constant actuation airgap while the device moves, for improved electrostatic control. With this nanoelectromechanical relay we demonstrate the first high-temperature non-volatile relay operation, with over 40 non-volatile cycles at 200 ∘C.

An uncommon presentation of non-small-cell lung cancer with acrometastases to the great toe and index finger.

BACKGROUND: Acrometastasis as initial presentation of metastatic cancer is an extremely rare finding. We describe an unusual case of late-stage non-small-cell lung cancer with metastatic lesions to the great toe and index fnger with associated pain in those areas as the only presenting symptom. CASE PRESENTATION AND SUMMARY: A 71-year-old white woman was referred to the emergency department by her primary care physician for necrosis and swelling of the left great toe for work-up of possible osteomyelitis (Figure 1). Before she presented to her physician, she had been complaining of severe pain, swelling, and erythema of the left great toe that had lasted for 1-2 months. Infection was initially suspected. She completed 2 courses of oral antibiotics with no improvement. She was also complaining of similar symptoms on the left index finger and attributed her symptoms to an injury a month earlier (Figure 2). The pain was so severe that she was not able to bear weight on her left foot. An outpatient X-ray of her left great toe raised her physician's concerns that it might be osteomyelitis so she was referred to the emergency department.

Bilateral adrenal haemorrhage associated with heparin-induced thrombocytopaenia during treatment of Fournier gangrene.

We present a case of bilateral adrenal haemorrhage (BAH) associated with heparin-induced thrombocytopaenia (HIT) in a 61-year-old man admitted to hospital for the treatment of Fournier's gangrene. He presented to hospital with scrotal swelling and fever, and developed spreading erythaema and a gangrenous scrotum. His scrotum was surgically debrided and intravenous broad-spectrum antibiotics were administered. Unfractionated heparin was given postoperatively for venous thromboembolism prophylaxis. The patient deteriorated clinically 8-11 days postoperatively with delirium, chest pain and severe hypertension followed by hypotension and thrombocytopaenia. Abdominal CT scan revealed bilateral adrenal haemorrhage. Antibodies to the heparin-platelet factor 4 complex were present. HIT-associated BAH was diagnosed and heparin was discontinued. Intravenous bivalirudin and hydrocortisone were started, with rapid improvement in clinical status. BAH is a rare complication of HIT and should be considered in the postoperative patient with unexplained clinical deterioration.

Micropapillary urothelial carcinoma of the urinary bladder: a clinicopathological analysis of 72 cases.

AIM: Micropapillary carcinoma (MPC) of the bladder is an aggressive variant of urothelial carcinoma (UC). It is unknown if any amount of a micropapillary component justifies the diagnosis of MPC. It is also unknown if surface MPC also has aggressive potential. METHODS: We studied 72 patients with UC with a micropapillary component in transurethral resections of bladder (TURB) diagnosed between 1998 and 2008. Fifty-seven patients were treated with radical cystectomy. Tumours were classified according to pathological (pT) stage and percentage of MPC (≤ 10%, 10-49%, 50-100%). This was correlated with clinical data and follow up. Significant factors in univariate analysis were entered into a multivariate analysis. RESULTS: In the TURB specimens, 12 had pTa, 33 pT1 and 27 pT2 tumours with 23% also displaying urothelial carcinoma in situ (CIS). On cystectomy, the MPC component was upstaged in 79% of cases. Twenty-five (35%) patients had metastases at presentation or nodal metastases at cystectomy and 27 patients (38%) died of disease. Mean survival was 17.8 months. Of 12 pTa MPC cases, eight were treated with cystectomy, all displaying invasive carcinoma including five (62%) with pT2-pT4 disease. Three (25%) of these patients died of disease. Seven patients had a MPC component of <10% all of whom had cystectomy. Six of these had invasive carcinoma including two (33%) with pT2-pT4 disease. One (15%) of these patients died of disease. On univariate analysis, the proportion of the MPC component on TURB and pathological stage predicted disease specific survival (p=0.01 and 0.004, respectively), while presence of CIS predicted recurrence (p=0.03). On multivariate analysis, CIS predicted recurrence (p=0.003); however, the proportion of MPC in TURB did not remain significant in predicting disease specific survival. The pathological stage of MPC remained significant in predicting disease specific survival (p=0.04). CONCLUSIONS: Any amount of MPC, even <10% is significant in urothelial carcinoma and should be reported. Surface MPC is associated with invasive carcinoma in most cases which can be high stage. Adequate sampling to include detrusor muscle is crucial in these cases. Associated CIS is important to be recognised and reported as this also impacts on clinical outcome.