Synthesis and properties of free-standing monolayer amorphous carbon.

Bulk amorphous materials have been studied extensively and are widely used, yet their atomic arrangement remains an open issue. Although they are generally believed to be Zachariasen continuous random networks, recent experimental evidence favours the competing crystallite model in the case of amorphous silicon. In two-dimensional materials, however,  the corresponding questions remain unanswered.

Colossal Ultraviolet Photoresponsivity of Few-Layer Black Phosphorus.

Black phosphorus has an orthorhombic layered structure with a layer-dependent direct band gap from monolayer to bulk, making this material an emerging material for photodetection. Inspired by this and the recent excitement over this material, we studied the optoelectronics characteristics of high-quality, few-layer black phosphorus-based photodetectors over a wide spectrum ranging from near-ultraviolet (UV) to near-infrared (NIR). It is demonstrated for the first time that black phosphorus can be configured as an excellent UV photodetector with a specific detectivity ∼3 × 10(13) Jones.

Unconventional transport through graphene on SrTiO₃: a plausible effect of SrTiO₃ phase-transitions.

High-k dielectric oxides are supposedly ideal gate-materials for ultra-high doping in graphene and other 2D-crystals. Here, we report a temperature-dependent electronic transport study on chemical vapor deposited-graphene gated with SrTiO₃ (STO) thin film substrate. At carrier densities away from charge neutrality point the temperature-dependent resistivity of our graphene samples on both STO and SiO₂/Si substrates show metallic behavior with contributions from Coulomb scattering and flexural phonons attributable to the presence of characteristic quasi-periodic nano-ripple arrays.

Nanometer thick elastic graphene engine.

Significant progress has been made in the construction and theoretical understanding of molecular motors because of their potential use. Here, we have demonstrated fabrication of a simple but powerful 1 nm thick graphene engine. The engine comprises a high elastic membrane-piston made of graphene and weakly chemisorbed ClF3 molecules as the high power volume changeable actuator, while a 532 nm LASER acts as the ignition plug.

Ultrathin organic solar cells with graphene doped by ferroelectric polarization.

Graphene has been employed as transparent electrodes in organic solar cells (OSCs) because of its good physical and optical properties. However, the electrical conductivity of graphene films synthesized by chemical vapor deposition (CVD) is still inferior to that of conventional indium tin oxide (ITO) electrodes of comparable transparency, resulting in a lower performance of OSCs. Here, we report an effective method to improve the performance and long-term stability of graphene-based OSCs using electrostatically doped graphene films via a ferroelectric polymer.

Tuning optical conductivity of large-scale CVD graphene by strain engineering.

A controllable optical anisotropy in CVD graphene is shown. The transparency in the visible range of pre-strained CVD graphene exhibits a periodic modulation as a function of polarization direction. The strain sensitivity of the optical response of graphene demonstrated here can be effectively utilized towards novel ultra-thin optical devices and strain sensing applications.

Flexible graphene-PZT ferroelectric nonvolatile memory.

We report the fabrication of a flexible graphene-based nonvolatile memory device using Pb(Zr0.35,Ti0.65)O3 (PZT) as the ferroelectric material.

Controlled hydrogenation of graphene sheets and nanoribbons.

The electronic properties of graphene sheets and nanoribbons with different degrees of hydrogenation have been investigated using a combination of charge transport and Raman spectroscopy experiments. The field-effect transistor mobility of graphene is shown to be highly sensitive to the treatment time during atomic hydrogen dose and follows an exponential decrease with time. Raman spectroscopy demonstrates linearly increasing defect-band intensity, and when considered together with transport data, the relationship between graphene mobility and the crystalline size of intact sp(2) carbon regions can be derived.

Graphene field-effect transistors with ferroelectric gating.

Recent experiments on ferroelectric gating have introduced a novel functionality, i.e., nonvolatility, in graphene field-effect transistors.

Management of Chronic Heart Failure in Primary Care: What Evidence do we have for Heart Failure with Preserved Systolic Function?

Chronic Heart Failure (CHF) is a debilitating illness commonly encountered in primary care. Its prevalence in developing countries is rising as a result of an ageing population, and an escalating epidemic of hypertension, type 2 diabetes and coronary heart disease. CHF can be specifically diagnosed as Heart Failure with Reduced Systolic Function (HF-RSF) or Heart Failure with Preserved Systolic Function (HF-PSF).

Rosai-Dorfman disease complicated by autoimmune haemolytic anaemia: case report and review of a multisystem disease with cutaneous infiltrates.

We report a patient with sinus histiocytosis with massive lymphadenopathy (Rosai-Dorfman disease) who presented with widespread nodal and extranodal involvement affecting the skin, orbits and nasal sinuses, complicated by the development of autoimmune haemolytic anaemia. The aetiology and pathogenesis of this multisystem disorder are unknown but are thought to represent a reactive histiocytic process to an infective agent rather than a neoplastic or other primary condition. Prognosis is generally good but clinical or laboratory evidence of immune dysfunction tends to predict a poorer outcome.

Aortocaval compression and plasma concentrations of thiopentone at caesarean section.

The venous plasma concentration-time profiles of thiopentone were measured simultaneously over the first 30-40 min after induction of anaesthesia, in blood obtained from an arm vein and a vein in the foot, in nine healthy full-term women undergoing Caesarean section. Patients were tilted laterally to the left by from 8 to 18 degrees during the procedure. In all but two of the patients, the profiles from the arm and foot were virtually identical, suggesting that aortocaval compression was absent or insignificant.