Free charge photogeneration in a single component high photovoltaic efficiency organic semiconductor.

Organic photovoltaics (OPVs) promise cheap and flexible solar energy. Whereas light generates free charges in silicon photovoltaics, excitons are normally formed in organic semiconductors due to their low dielectric constants, and require molecular heterojunctions to split into charges. Recent record efficiency OPVs utilise the small molecule, Y6, and its analogues, which - unlike previous organic semiconductors - have low band-gaps and high dielectric constants.

Spontaneous exciton dissociation enables spin state interconversion in delayed fluorescence organic semiconductors.

Engineering a low singlet-triplet energy gap (ΔE) is necessary for efficient reverse intersystem crossing (rISC) in delayed fluorescence (DF) organic semiconductors but results in a small radiative rate that limits performance in LEDs. Here, we study a model DF material, BF2, that exhibits a strong optical absorption (absorption coefficient = 3.8 × 10cm) and a relatively large ΔE of 0.

Highly efficient blue organic light-emitting diodes based on carbene-metal-amides.

Carbene-metal-amides are soluble and thermally stable materials which have recently emerged as emitters in high-performance organic light-emitting diodes. Here we synthesise carbene-metal-amide photoemitters with CF-substituted ligands to show sky-blue to deep-blue photoluminescence from charge-transfer excited states. We demonstrate that the emission colour can be adjusted from blue to yellow and observe that the relative energies of charge transfer and locally excited triplet states influence the performance of the deep-blue emission.

Carbene metal amide photoemitters: tailoring conformationally flexible amides for full color range emissions including white-emitting OLED.

Conformationally flexible "Carbene-Metal-Amide" (CMA) complexes of copper and gold have been developed based on a combination of sterically hindered cyclic (alkyl)(amino)carbene (CAAC) and 6- and 7-ring heterocyclic amide ligands. These complexes show photoemissions across the visible spectrum with PL quantum yields of up to 89% in solution and 83% in host-guest films. Single crystal X-ray diffraction and photoluminescence (PL) studies combined with DFT calculations indicate the important role of ring structure and conformational flexibility of the amide ligands.

A Simple Molecular Design Strategy for Delayed Fluorescence toward 1000 nm.

Harnessing the near-infrared (NIR) region of the electromagnetic spectrum is exceedingly important for photovoltaics, telecommunications, and the biomedical sciences. While thermally activated delayed fluorescent (TADF) materials have attracted much interest due to their intense luminescence and narrow exchange energies (Δ), they are still greatly inferior to conventional fluorescent dyes in the NIR, which precludes their application. This is because securing a sufficiently strong donor-acceptor (D-A) interaction for NIR emission alongside the narrow Δ required for TADF is highly challenging.

Efficient Vacuum-Processed Light-Emitting Diodes Based on Carbene-Metal-Amides.

Efficient vacuum-processed organic light-emitting diodes are fabricated using a carbene-metal-amide material, CMA1. An electroluminescence (EL) external quantum efficiency of 23% is achieved in a host-free emissive layer comprising pure CMA1. Furthermore external quantum efficiencies of up to 26.

A randomised controlled trial of the efficacy of ultrasound-guided transversus abdominis plane (TAP) block in laparoscopic colorectal surgery.

Background: Optimal analgesia following laparoscopic colorectal resection is yet to be determined; however, recent studies have questioned the role of postoperative epidural anaesthesia, suggesting other analgesic modalities may be preferable. The aim of this randomised controlled trial was to assess the effect of transversus abdominis plane (TAP) blocks on opioid requirements in patients undergoing laparoscopic colorectal resection.

Methods: After appropriate trial registration ( www.

Leaving a mark: the frequency and accuracy of tattooing prior to laparoscopic colorectal surgery.

Aim: Intra-operative localization of small cancers and polyps during laparoscopic colorectal surgery is difficult due to reduced tactile feedback. The consequences of failing to identify the lesion for resection can result in open conversion or removal of the wrong segment of bowel.

Method: Data were collected from a prospectively-kept database over a 12-month period from April 2008 to March 2009 and analysed retrospectively.

Targeted killing of colorectal cancer cell lines by a humanised IgG1 monoclonal antibody that binds to membrane-bound carcinoembryonic antigen.

The distribution of carcinoembryonic antigen (CEA) in colorectal cancer (CRC) differs from that in normal colorectal tissue, being found on all borders of the cell membrane and hence enabling access to intravenous antibody, making CEA a good target for antibody-based therapy. The distinctive anti-CEA antibody, PR1A3, binds only membrane-bound CEA. Humanised PR1A3 (hPR1A3) was assessed both in vitro cytotoxicity and binding assays with colorectal cancer cell lines expressing varying levels of CEA.

Comparison of ankle-brachial pressure index measurements using an automated oscillometric device with the standard Doppler ultrasound technique.

Background: The aim of the present study was to assess the accuracy of an automated oscillometric device (DINAMAP) in measuring ankle-brachial pressure index (ABPI) in the clinical setting. Results were then compared to those obtained using the standard Doppler technique.

Methods: A prospective comparative study of 50 healthy volunteers was carried out using a standard ward DINAMAP machine, hand-held Doppler and a 14 cm sphygmomanometer cuff.

Randomized clinical trial of the effectiveness of emergency day surgery against standard inpatient treatment.

Background: The aim of this study was to assess the feasibility of treating patients with minor and intermediate general surgical emergency conditions as day cases.

Methods: Emergency referrals for minor and intermediate general surgical conditions were assessed by a surgeon. Those fitting day-case criteria and requiring operation under general anaesthesia were randomized to receive standard inpatient care or day surgery.

Education provision for surgical senior house officers.

The provision of formal education in surgical SHO training is a requirement for posts to be accredited by postgraduate deans. We carried out a questionnaire survey of surgical SHOs attending a Royal College of Surgeons of England study day to quantify the amount of time given to formal education and supervised operating. We found that 79% of SHOs at district general hospitals and 87.