K α X-ray sources generated from the interaction of ultra-short laser pulses with solids are compact and low-cost source of ultra-short quasi-monochromatic X-rays compared with synchrotron radiation source. Development of collimated ultra-short K α X-ray source by the interaction of 45 fs Ti:sapphire laser pulse with Cu wire target is presented in this paper. A study of the K α source with laser parameters such as energy and pulse duration was carried out. The observed K α X-ray photon flux was ~2.7 × 108 photons/shot at the laser intensity of ~2.8 × 1017 W cm−2. A model was developed to analyze the observed results. The K α radiation was coupled to a polycapillary collimator to generate a collimated low divergence (0.8 mrad) X-ray beam. Such sources are useful for time-resolved X-ray diffraction and imaging studies.

From the photoinduced transport of energy that accompanies photosynthesis to the transcontinental transmission of optical data that enable the Internet, our world relies and thrives on optical signals. To highlight the importance of optics to society, the United Nations designated 2015 as “The International Year of Light and Light-based Technologies.” Although conventional optical technologies are limited by diffraction, plasmons—collective oscillations of free electrons in a conductor—allow optical signals to be tailored with nanoscale precision. Following decades of fundamental research, several plasmonic technologies have now emerged on the market, and numerous industrial breakthroughs are imminent. This article highlights recent industrially relevant advances in plasmonics, including plasmonic materials and devices for energy; for medical sensing, imaging, and therapeutics; and for information technology. Some of the most exciting industrial applications include solar-driven water purifiers, cell phone Raman spectrometers, high-density holographic displays, photothermal cancer therapeutics, and nanophotonic integrated circuits. We describe the fundamental scientific concepts behind these and related technologies, as well as the successes and challenges associated with technology transfer.

In June 2014 Public Health England confirmed a case of Legionnaires' disease (LD) in a neonate following birth at home in a hired birthing pool incorporating a heater and a recirculation pump which had been filled in advance of labour. The case triggered a public health investigation and a microbiological survey of an additional ten heated birthing pools hired or recently hired to the general public across England. The birthing pool used by the parent of the confirmed case was identified as the source of the neonate's infection following detection of Legionella pneumophila ST48 in both patient and environmental samples. Legionella species were detected by quantitative polymerase chain reaction but not culture in a further three pools together with other opportunistic pathogens identified by culture and matrix-assisted laser desorption ionization–time of flight (MALDI–ToF) mass spectrometry. A Patient Safety Alert from NHS England and Public Health England was issued stating that heated birthing pools filled in advance of labour should not be used for home births. This recommendation remains in place. This investigation in conjunction with other recent reports has highlighted a lack of awareness regarding the microbiological safety of heated birthing pools and their potential to be a source of LD and other opportunistic infections. Furthermore, the investigation raised important considerations with regards to microbiological sampling and testing in such incidents. Public health authorities and clinicians should consider LD in the differential diagnosis of severe respiratory infection in neonates within 14 days of a water birth.

The effect of adding nucleic acids to gold seeds during the growth stage of either nanospheres or nanorods was investigated using UV–Vis spectroscopy to reveal any oligonucleotide base or structure-specific effects on nanoparticle growth kinetics or plasmonic signatures. Spectral data indicate that the presence of DNA duplexes during seed aging drastically accelerated nanosphere growth while the addition of single-stranded polyadenine at any point during seed aging induces nanosphere aggregation. For seeds added to a gold nanorod growth solution, single-stranded polythymine induces a modest blue shift in the longitudinal peak wave length. Moreover, a particular sequence comprised of 50% thymine bases was found to induce a faster, more dramatic blue shift in the longitudinal peak wave length compared to any of the homopolymer incubation cases. Monomeric forms of the nucleic acids, however, do not yield discernable spectral differences in any of the gold suspensions studied.

A community outbreak of legionellosis occurred in Barrow-in-Furness, Cumbria, during July and August 2002. A descriptive study and active case-finding were instigated and all known wet cooling systems and other potential sources were investigated. Genotypic and phenotypic analysis, and amplified fragment length polymorphism of clinical human and environmental isolates confirmed the air-conditioning unit of a council-owned arts and leisure centre to be the source of infection. Subsequent sequence-based typing confirmed this link. One hundred and seventy-nine cases, including seven deaths [case fatality rate (CFR) 3·9%] were attributed to the outbreak. Timely recognition and management of the incident very likely led to the low CFR compared to other outbreaks. The outbreak highlights the responsibility associated with managing an aerosol-producing system, with the potential to expose and infect a large proportion of the local population and the consequent legal ramifications and human cost.

Monoclonal antibodies specific for rotavirus subgroup 1 (SG1) and subgroup 2 (SG2) were used to analyse by enzyme immunoassay (EIA) the subgroups of human rotavirus isolates obtained from three different parts of India during the period September 1985 to July 1987. We identified one isolate which failed to react with either SG1 or SG2 specific monoclonal antibodies, although it reacted well with a monoclonal antibody specific for group A rotaviruses. This finding suggests that it belongs to a new rotavirus subgroup. Further, another isolate was found to belong to SG1 although it had a ‘long’ electropherotype.

An experimental study of laser-driven shock wave propagation in a transparent material such as Plexiglas using a high-speed optical shadowgraphy technique is presented in this paper. A Nd:glass laser was used to produce laser intensity in the range 1012-1014 W/cm2 on the target. Optical shadowgrams of the propagating shock front were recorded with a second-harmonic (0.53-μm) optical probe beam. Shock pressures were measured at various laser intensities, and the scaling was found to agree with the theoretically predicted value. Shock pressure values have also been obtained from a one-dimensional Lagrangian hydrodynamic simulation, and they match well with experimental results. Shadowgrams of shock fronts produced by nonuniform spatial laser beam irradiation profiles have shown complete smoothing when targets with a thin coating of a material of high atomic number such as gold were used. Shock pressures in such coated targets are also found to be considerably higher compared with those in uncoated targets.

During a surveillance study (2003–2005) in a cattle market in Kolkata city, state of West Bengal, Eastern India, 34 (13·0%) of 260 calves with diarrhoea were positive for group B rotaviruses (GBR) by RNA electrophoresis in polyacrylamide gels. Analysis of the partial VP7 gene sequence of 28 of the 34 GBR strains revealed maximum identities (97·7–99·5% at nucleotide level and 97·8–100% at amino-acid level) with the novel bovine GBR ‘Kolkata strains’ reported in an earlier surveillance study (1·5%, n=192, 2001–2002) from the same cattle market, and shared low identities of 73·7–78·9% and 80·8–89·6%; 62·6–66·2% and 59·8–65·4%; 58·9–62·2% and 48·6–54·9% at nucleotide and amino-acid level with other bovine, human, and murine GBR. The GBR-infected calves were traced to districts in neighbouring states of West Bengal. Therefore, the present study reports a rapid increase in prevalence (13·0% in 2003–2005 against 1·5% in 2001–2002) of novel GBR strains among calves with diarrhoea, and provides evidence for interstate transmission of GBR.

Summary

Background and objectives: The sustained attention to response task (SART) test is a sensitive indicator of deficits in sustained attention and is simple to perform. Sustained attention is impaired for a short period after minor surgery under general anaesthesia but the magnitude and duration of this effect after major surgery is unknown. We used the SART test to investigate deficits in sustained attention in patients undergoing major surgery under general anaesthesia. Methods: The SART test was completed before surgery and at 24, 48 and 72 h postoperatively by 20 ASA I–II female patients (mean age 48.6 yr) undergoing total abdominal hysterectomy under general anaesthesia. It was also completed by 20 age-matched female controls at similar time intervals to evaluate the effect of repeated test performance. Results: There was a significant (P < 0.05) interaction between the groups in number of errors made (a measure of sustained attention deficit). The number of errors decreased in control subjects on repeated performance of the SART test but remained unchanged in patients undergoing total abdominal hysterectomy. The differences between groups remained significant after 72 h (P < 0.05). Patients' overall response times slowed significantly at 24–48 h (P < 0.05), but this recovered by 72 h after surgery. In contrast, overall response times in the control group tended to accelerate on repeated performance of the SART. Conclusions: The results of this study suggest that 72 h following major surgery patients have deficits in sustained attention compared with controls. Control subjects demonstrated a marked learning effect on repeated test performance compared with patients.

The temperature and power dependence of Fermi-edge singularity (FES) in high-density two-dimensional electron gas, specific to pseudomorphic AlxGa1-xAs/InyGa1-yAs/GaAs heterostructures is studied by photoluminescence (PL). In all these structures, there are two prominent transitions E11 and E21 considered to be the result of electron-hole recombination from first and second electron sub-bands with that of first heavy-hole sub-band. FES is observed approximately 5 -10 meV below the E21 transition. At 4.2 K, FES appears as a lower energy shoulder to the E21 transition. The PL intensity of all the three transitions E11, FES and E21 grows linearly with excitation power. However, we observe anomalous behavior of FES with temperature. While PL intensity of E11 and E21 decrease with increasing temperature, FES transition becomes stronger initially and then quenches-off slowly (till 40K). Though it appears as a distinct peak at about 20 K, its maximum is around 7 - 13 K.

SrBi2Ta2O9 (SBT) samples have been prepared by sol-gel technique with varying amount of excess Bi added to the starting composition. The excess Bi profoundly affects the dielectric and ferroelectric properties. The dielectric constant (ε) and remnant polarization increases from 80 and 1.4 μ C/cm2 for SBT with 1 mole % of excess Bi to 120 and 6.5 μ C/cm2 for SBT with 20 mole % of excess Bi. The Raman spectra, scanning electron microscopy images and the x-ray diffraction analysis show an improvement in structural quality of the samples with addition of excess Bi to the starting composition. The effect of Mn doping has also been studied by preparing SrBi2Ta2-x Mnx O9 (SBT-Mn) with x = 0 – 0.1. In the case of SBT-Mn samples, the XRD spectra revealed an unknown phase when x > 0.025. However, Raman spectra reveal the retention of Bi layer structure for all Mn compositions, with possibly small distortions. With Mn addition, ε increased to ∼ 140 for x < 0.005, but decreased to ≤ 120 when x > 0.015. The value of ε is independent of frequency from 60 to 85 kHz for all compositions of Mn. The effect of Mn addition resulted in a strong decrease in the area of the hysteresis loops.

The precise pore sizes defined by crystalline zeolite lattices have led to intensive research on zeolite membranes. Unfortunately zeolites have proven to be extremely difficult to prepare in a defect-free thin film form needed for membrane flux and selectivity. We introduce tetrapropylammonium TPA (a structure directing agent for zeolite ZSM-5) into a silica sol and exploit the development of high solvation stresses to create templated amorphous silicas with pore apertures comparable in size to those of ZSM-5. 29Si and 2H NMR experiments were performed to evaluate the efficacy of our templating approach. The 29Si NMR spectrum of the silica matrix was observed by an intermolecular cross-polarization experiment between the 1H nuclei of TPA and the 29Si nuclei in the silica matrix. The efficiency of the cross-polarization interaction was used to investigate the degree to which the matrix formed a tight cage surrounding the template molecule. Bulk xerogels, prepared by gelation and slow drying of the corresponding sols, exhibited only weak interactions between the two sets of nuclei. Thin film xeorgels, where drying stresses are greater, resulted in significantly increased interactions. Analogous materials were prepared using fully deuterated TPA. The 2H NMR wideline spectra consisted of a partially narrowed resonance, corresponding to template molecules which were undergoing restricted rotational motion, and an isotropically narrowed resonance, corresponding to molecules which were undergoing rapid rotational motion. The number of isotropically rotating template molecules decreased for the thin film specimens, consistent with improved templating of amorphous silica by TPA.

This is a retrospective study of 173 consecutive admissions to a general psychiatric hospital. The aim was to establish the frequency and adequacy with which alcohol and tobacco use were recorded. Regarding alcohol, in 41% of the notes there was no adequate quantitative history, in 29.5% there was a descriptive mention and in 29.5% no history was recorded. Female patients were less likely to have an alcohol history taken than male patients. With tobacco, in 64% of the notes there was an adequate quantitative history, in 6.4% there was a descriptive comment and in 28.9% no history was recorded. It is to be stressed to all doctors that an assessment of alcohol and tobacco use should be made for every patient, whatever their age, gender or ethnic origin.

In the study of suicide little attention has been paid to the role of life insurance. One might suppose that ‘deliberately accelerating the event insured against’ by homicide or suicide would void a policy. One might also predict that changes in attitude towards suicide, so that it is increasingly regarded as a medico-social problem rather than a criminal act, would be reflected in a softening of attitude among insurers. On the other hand, recent epidemiological changes, such as the increased suicide rate among young males, could make companies reluctant to relax their policy conditions.