Synthesis and ring-opening metathesis polymerisation of o-alkoxy benzothiadiazole paracyclophane-1,9-dienes.

ortho-Diethylhexyloxyphenylene benzothiadiazole paracyclophane-1,9-diene as a mixture of diastereomers was synthesized by a sequential benzyne-induced Stevens rearrangement, oxidation and pyrolysis of a dithia[3.3]paracyclophane. Reaction of these highly strained cyclophanedienes with the second generation Grubbs catalyst showed that they can be ring opened to alternating cis,trans-phenylenevinylene polymers. In situ NMR experiments showed that one isomer 8a polymerised to 90% conversion, whereas the other 8b gave only 9% conversion due to steric hindrance on both faces of the alkene bridges of this isomer. The resulting polymers can be readily isomerized in dilute solution using visible light to the all-trans isomer and the optical and electrochemical properties of these polymers were examined by theory and experiment.

Electrolyte-Gated Organic Field-Effect Transistors for Quantitative Monitoring of the Molecular Dynamics of Crystallization at the Solid-Liquid Interface.

Quantitative measurements of molecular dynamics at the solid-liquid interface are of crucial importance in a wide range of fields, such as heterogeneous catalysis, energy storage, nanofluidics, biosensing, and crystallization. In particular, the molecular dynamics associated with nucleation and crystal growth is very challenging to study because of the poor sensitivity or limited spatial/temporal resolution of the most widely used analytical techniques. We demonstrate that electrolyte-gated organic field-effect transistors (EGOFETs) are able to monitor in real-time the crystallization process in an evaporating droplet. The high sensitivity of these devices at the solid-liquid interface, through the electrical double layer and signal amplification, enables the quantification of changes in solute concentration over time and the transport rate of molecules at the solid-liquid interface during crystallization. Our results show that EGOFETs offer a highly sensitive and powerful, yet simple approach to investigate the molecular dynamics of compounds crystallizing from water.

Modular synthesis of unsymmetrical [1]benzothieno[3,2-b][1]benzothiophene molecular semiconductors for organic transistors.

A modular approach to underexplored, unsymmetrical [1]benzothieno[3,2-b][1]benzothiophene (BTBT) scaffolds delivers a library of BTBT materials from readily available coupling partners by combining a transition-metal free Pummerer CH-CH-type cross-coupling and a Newman-Kwart reaction. This effective approach to unsymmetrical BTBT materials has allowed their properties to be studied. In particular, tuning the functional groups on the BTBT scaffold allows the solid-state assembly and molecular orbital energy levels to be modulated. Investigation of the charge transport properties of BTBT-containing small-molecule:polymer blends revealed the importance of molecular ordering during phase segregation and matching the highest occupied molecular orbital energy level with that of the semiconducting polymer binder, polyindacenodithiophene-benzothiadiazole (PIDTBT). The hole mobilities extracted from transistors fabricated using blends of PIDTBT with phenyl or methoxy functionalized unsymmetrical BTBTs were double those measured for devices fabricated using pristine PIDTBT. This study underscores the value of the synthetic methodology in providing a platform from which to study structure-property relationships in an underrepresented family of unsymmetrical BTBT molecular semiconductors.

Synthesis and Ring-Opening Metathesis Polymerization of o-Dialkoxy Paracyclophanedienes.

The highly strained ortho-diethylhexyloxy [2.2]paracyclophane-1,9-diene (M1) can be synthesized by ring contraction of a dithia[3.3]paracyclophane using a benzyne-induced Stevens rearrangement. This paracyclophanediene undergoes ring-opening metathesis polymerization to give well-defined 2,3-dialkoxyphenylenevinylene polymers with an alternating cis/trans alkene stereochemistry and controllable molecular weight. Fully conjugated block copolymers with electron-rich and electron-deficient phenylene vinylene polymer segments can be prepared by sequential monomer additions. These polymers can be readily isomerized to the all-trans stereochemistry polymer. The optical and electrochemical properties of these polymers were investigated by theory and experiment.

Organic Semiconductors Processed from Synthesis-to-Device in Water.

Organic semiconductors (OSCs) promise to deliver next-generation electronic and energy devices that are flexible, scalable and printable. Unfortunately, realizing this opportunity is hampered by increasing concerns about the use of volatile organic compounds (VOCs), particularly toxic halogenated solvents that are detrimental to the environment and human health. Here, a cradle-to-grave process is reported to achieve high performance p- and n-type OSC devices based on indacenodithiophene and diketopyrrolopyrrole semiconducting polymers that utilizes aqueous-processes, fewer steps, lower reaction temperatures, a significant reduction in VOCs (>99%) and avoids all halogenated solvents. The process involves an aqueous mini-emulsion polymerization that generates a surfactant-stabilized aqueous dispersion of OSC nanoparticles at sufficient concentration to permit direct aqueous processing into thin films for use in organic field-effect transistors. Promisingly, the performance of these devices is comparable to those prepared using conventional synthesis and processing procedures optimized for large amounts of VOCs and halogenated solvents. Ultimately, the holistic approach reported addresses the environmental issues and enables a viable guideline for the delivery of future OSC devices using only aqueous media for synthesis, purification and thin-film processing.

Audit of electronic operative documentation in interventional radiology: the value of standardised proformas.

BACKGROUND: On the background of the interventional radiology department of a tertiary hospital converting its periprocedural documentation from paper-based to electronic using a standardised proforma, a study was performed to ascertain the effects of this change on the standard of clinical documentation for radiologically-guided angiographic procedures. Using a retrospective approach, perioperative records were analysed in reverse chronological order for inclusion in the study. The standard for this audit was developed in the form of minimum criteria that all clinical documentation of angiographic procedures were expected to meet. RESULTS: The audit was performed at three equally spaced intervals of 6 months, yielding a total of 99 records. The baseline audit of paper-based records concluded > 80% completeness for 8 out of the 14 of parameters measured, with only two of parameters meeting the target of 100% completeness. The second audit cycle performed on electronic records found 7 out of 14 parameters demonstrating absolute improvement in completeness, when compared to paper-based, but with the number of parameters exceeding 80% completeness falling to only 4 out of 14. Again, 100% completeness was observed in only 2 of the parameters. In the final audit cycle, after the introduction of a standardised electronic proforma, performance improved in every dimension with 6 out of 14 parameters reaching completeness of 100% and the 80% completeness threshold met by 12 out of 14 parameters. CONCLUSION: The construction of a procedure-specific perioperative electronic proforma can save clinicians valuable time and encourage safe and effective clinical documentation.

Two photon spectroscopy and microscopy of the fluorescent flavoprotein, iLOV.

LOV-domains are ubiquitous photosensory proteins that are commonly re-engineered to serve as powerful and versatile fluorescent proteins and optogenetic tools. The photoactive, flavin chromophore, however, is excited using short wavelengths of light in the blue and UV regions, which have limited penetration into biological samples and can cause photodamage. Here, we have used non-linear spectroscopy and microscopy of the fluorescent protein, iLOV, to reveal that functional variants of LOV can be activated to great effect by two non-resonant photons of lower energy, near infrared light, not only in solution but also in biological samples. The two photon cross section of iLOV has a significantly blue-shifted S0 → S1 transition compared with the one photon absorption spectrum, suggesting preferential population of excited vibronic states. It is highly likely, therefore, that the two photon absorption wavelength of engineered, LOV-based tools is tuneable. We also demonstrate for the first time two photon imaging using iLOV in human epithelial kidney cells. Consequently, two photon absorption by engineered, flavin-based bio-molecular tools can enable non-invasive activation with high depth resolution and the potential for not only improved image clarity but also enhanced spatiotemporal control for optogenetic applications.

Assessing the effects of manual dexterity and playing computer games on catheter-wire manipulation for inexperienced operators.

AIM: To investigate the effect of playing computer games and manual dexterity on catheter-wire manipulation in a mechanical aortic model. MATERIAL AND METHODS: Medical student volunteers filled in a preprocedure questionnaire assessing their exposure to computer games. Their manual dexterity was measured using a smartphone game. They were then shown a video clip demonstrating renal artery cannulation and were asked to reproduce this. All attempts were timed. Two-tailed Student's t-test was used to compare continuous data, while Fisher's exact test was used for categorical data. RESULTS: Fifty students aged 18-22 years took part in the study. Forty-six completed the task at an average of 168 seconds (range 103-301 seconds). There was no significant difference in the dexterity score or time to cannulate the renal artery between male and female students. Students who played computer games for >10 hours per week had better dexterity scores than those who did not play computer games: 9.1 versus 10.2 seconds (p=0.0237). Four of 19 students who did not play computer games failed to complete the task, while all of those who played computer games regularly completed the task (p=0.0168). CONCLUSION: Playing computer games is associated with better manual dexterity and ability to complete a basic interventional radiology task for novices.

New stability criterion of neural networks with leakage delays and impulses: a piecewise delay method.

This paper analyzes the global asymptotic stability of a class of neural networks with time delay in the leakage term and time-varying delays under impulsive perturbations. Here the time-varying delays are assumed to be piecewise. In this method, the interval of the variation is divided into two subintervals by its central point. By developing a new Lyapunov-Krasovskii functional and checking its variation in between the two subintervals, respectively, and then we present some sufficient conditions to guarantee the global asymptotic stability of the equilibrium point for the considered neural network. The proposed results which do not require the boundedness, differentiability and monotonicity of the activation functions, can be easily verified via the linear matrix inequality (LMI) control toolbox in MATLAB. Finally, a numerical example and its simulation are given to show the conditions obtained are new and less conservative than some existing ones in the literature.

The implications of a raised maternal BMI: a DGH experience.

This retrospective analysis evaluated the association between maternal body mass index (BMI) and the incidence of maternal and neonatal complications in those women delivering at a North West London hospital between January 2002 and December 2007. Of the women examined, obese mothers (BMI ≥ 30) were shown to be at significantly higher risk from multiple morbidities (p < 0.05), including gestational diabetes; antepartum haemorrhages; pre-term delivery before 37 and 33 weeks' gestation; induction of labour; analgesia use (beyond inhalational methods and local infiltration); caesarean sections; massive postpartum haemorrhages; higher birth weights; Apgar scores < 8 at 1 min and 5 min; cord base deficits less than-12 and a greater need for neonatal care (SCBU, HDU, NICU) compared with mothers with a BMI < 30. These findings add to the growing consensus that obesity increases the risks involved with pregnancy. While information is filtering through to the general public about the overall risks of obesity, more focused pre-pregnancy and inter-pregnancy counselling on the implications of a raised BMI specifically on pregnancy is required at both primary and secondary care sector levels.

Drug-induced sensorineural deafness caused by antithyroid drugs: a rare side effect.

Acute ototoxicity is a rare but important complication of antithyroid drugs. Although previous cases have been reported in the medical literature, these cases occurred in younger patients with serological evidence of lupus-like syndrome with positive antidouble-stranded deoxyribonucleic acid and antineutrophil cytoplasmic antibodies. We describe the case of a 68-year-old Caucasian male who developed deafness and tinnitus one week after being prescribed carbimazole. The management options include stopping the culprit drug, treatment with immunosuppressive drugs and referring the patient for urgent thyroidectomy. Healthcare professionals who prescribe antithyroid drugs should be aware of this rare but potentially serious complication, so that early drug withdrawal and referral for surgery can be considered.

How accurate are the references in Emergency Medical Journal?

OBJECTIVE: To determine the accuracy of references in Emergency Medicine Journal during 2003. MATERIALS AND METHODS: All references cited in Emergency Medicine Journal during 2003 were examined carefully, and the accuracy of the citations was checked against reliable electronic and manual resources. References were categorised as correct or incorrect. The errors were classified as minor if the integrity of the reference was not greatly compromised and major if the error severely detracted from the quality of the reference. RESULTS: Overall, errors were found in 19% of all citations checked (n = 2561), and in 8% the errors were major and markedly detracted from the quality of the reference. CONCLUSIONS: Citation errors reflect badly on authors and the publishing journal and may reflect underlying flaws in other areas of the research published. It is hoped that identification of this problem will lead to attempts to improve the accuracy of reference citation in the emergency medicine literature and to an improvement in the credibility of research in our specialty.

Pseudolipoma of inverted Meckel's diverticulum: clinical, radiological and pathological correlation.

Three cases of isolated inverted Meckel's diverticulum are described. In two cases an initial pathological diagnosis of small bowel lipoma was suggested. In a third case central fat was demonstrated on CT and peristalsis of the intraluminal polypoid mass was observed during US examination. In all three cases small bowel enema examination demonstrated the lesion. Correlation of the clinical, radiological and pathological features is emphasised, as this will allow the correct diagnosis.

Decapitation--a rare complication in hanging.

Decapitation from hanging is rare and there appears to be a lack of reports in scientific literature. Two cases of this phenomenon are reported.