Creation of a 50,000λ long needle-like field with 0.36λ width: comment.

In a recent paper, a method for the generation of a long, narrow needle of light was proposed [J. Opt. Soc.

Medical tourism and bariatric surgery: who pays?

Introduction: The objective of this study was to determine the short-term cost impact that medical tourism for bariatric surgery has on a public healthcare system. Due to long wait times for bariatric surgery services, Canadians are venturing to private clinics in other provinces/countries. Postoperative care in this population not only burdens the provincial health system with intervention costs required for complicated patients, but may also impact resources allotted to patients in the public clinic.

Mitotic activation of the DISC1-inducible cyclic AMP phosphodiesterase-4D9 (PDE4D9), through multi-site phosphorylation, influences cell cycle progression.

In Rat-1 cells, the dramatic decrease in the levels of both intracellular cyclic 3'5' adenosine monophosphate (cyclic AMP; cAMP) and in the activity of cAMP-activated protein kinase A (PKA) observed in mitosis was paralleled by a profound increase in cAMP hydrolyzing phosphodiesterase-4 (PDE4) activity. The decrease in PKA activity, which occurs during mitosis, was attributable to PDE4 activation as the PDE4 selective inhibitor, rolipram, but not the phosphodiesterase-3 (PDE3) inhibitor, cilostamide, specifically ablated this cell cycle-dependent effect. PDE4 inhibition caused Rat-1 cells to move from S phase into G2/M more rapidly, to transit through G2/M more quickly and to remain in G1 for a longer period.

The cost of bariatric medical tourism on the Canadian healthcare system.

Background: Medical tourists are defined as individuals who intentionally travel from their home province/country to receive medical care. Minimal literature exists on the cost of postoperative care and complications for medical tourists. The costs associated with these patients were reviewed.

Multipole and plane wave expansions of diverging and converging fields.

This paper presents and compares two basis systems, spherical harmonics and plane waves, for studying diverging and converging beams in an optical system. We show a similarity between a converging field and the time reversed field of a radiation field. We present and analyze the differences between the Debye-Wolf diffraction integral and the multipole theory for focusing of polarized light.

The sabotage of the bacterial transcription machinery by a small bacteriophage protein.

Many bacteriophages produce small proteins that specifically interfere with the bacterial host transcription machinery and thus contribute to the acquisition of the bacterial cell by the bacteriophage. We recently described how a small protein, called P7, produced by the Xp10 bacteriophage inhibits bacterial transcription initiation by causing the dissociation of the promoter specificity sigma factor subunit from the host RNA polymerase holoenzyme. In this addendum to the original publication, we present the highlights of that research.

Analytic method to optimize aperture design in focal modulation microscopy.

Focal modulation microscopy (FMM) has been demonstrated more effective than confocal microscopy for imaging of thick biological tissues. To improve its penetration depth further, we propose a simple analytical method to enlarge the modulation depth, the unique property of FMM directly linked to its signal-to-noise ratio. The modulation depth increases as the excitation intensity of the binary phase aperture status is pushed further away from the focal region of the detection optics, thereby creating a dark region in the focal volume, which we call maximally flat crater (MFC).

Focusing of vortex beams: Lommel treatment.

Focusing of vortex beams by a lens with circular aperture in the paraxial scalar Debye regime is analyzed. The amplitude in the focal region can be expressed naturally in terms of higher order Lommel functions of two variables. Using recurrence relationships, these can then be expressed in terms of low-order Lommel functions.

Pneumococcal carriage in children and adults two years after introduction of the thirteen valent pneumococcal conjugate vaccine in England.

Background/aims: In April 2010 the 7-valent pneumococcal conjugate vaccine (PCV7) was replaced by the 13-valent PCV. We investigated pneumococcal carriage in children eligible for PCV7 or PCV13 and their household contacts.

Methods: Eligible families in Hertfordshire and Gloucester were identified and a nasopharyngeal swab obtained from consenting household members between July 2012 and March 2013.

Clinical features of adults with seven-valent-conjugated-vaccine-serotype pneumococcal pneumonia.

Background: Despite the reduction in adult invasive pneumococcal disease through 'herd protection' consequent to the introduction of childhood pneumococcal conjugate vaccination (PCV), a significant proportion of adults continue to develop pneumococcal pneumonia caused by one of the seven serotypes included in the seven-valent conjugated pneumococcal vaccine (PCV7). The clinical features and outcomes of these adults have not been previously reported.

Methods: Adults recruited over a three year period to a large prospective cohort study of community acquired pneumonia (CAP) were investigated for pneumococcal serotypes using a validated multiplex immunoassay (Bio-plex).

A bacteriophage transcription regulator inhibits bacterial transcription initiation by σ-factor displacement.

Bacteriophages (phages) appropriate essential processes of bacterial hosts to benefit their own development. The multisubunit bacterial RNA polymerase (RNAp) enzyme, which catalyses DNA transcription, is targeted by phage-encoded transcription regulators that selectively modulate its activity. Here, we describe the structural and mechanistic basis for the inhibition of bacterial RNAp by the transcription regulator P7 encoded by Xanthomonas oryzae phage Xp10.

The economic impact of weight regain.

Background. Obesity is well known for being associated with significant economic repercussions. Bariatric surgery is the only evidence-based solution to this problem as well as a cost-effective method of addressing the concern.

Predicting plant invasions under climate change: are species distribution models validated by field trials?

Climate change may facilitate alien species invasion into new areas, particularly for species from warm native ranges introduced into areas currently marginal for temperature. Although conclusions from modelling approaches and experimental studies are generally similar, combining the two approaches has rarely occurred. The aim of this study was to validate species distribution models by conducting field trials in sites of differing suitability as predicted by the models, thus increasing confidence in their ability to assess invasion risk.

Rigorous analytical modeling of high-aperture focusing through a spherical interface.

High-aperture focusing through a spherical interface has been employed in optical data storage, photolithography, and especially microscopy. This paper first forms an approximate model, based on geometrical optics and Fourier optics, for evaluating focal fields of the focusing systems. This approximate model helps to clarify some doubts existing in literature.

Rayleigh-Sommerfeld diffraction formula in k space.

An angular spectrum representation in three dimensions is used to develop three-dimensional Fourier forms of the first and second Rayleigh-Sommerfeld diffraction formulae and the Kirchhoff diffraction formula. For forward-propagating waves, these reduce to three-dimensional Fourier representations for diffraction in the forward half-space.

Balanced diffraction aberrations, independent of the observation point: application to a tilted dielectric plate.

Balancing of Zernike aberrations breaks down if the defocus term is large enough that the condition (z/λ)≪2/[π(NA)⁴] is not satisfied. A modified Zernike aberration expansion, based on the Zernike aberrations, is developed that accurately includes axial displacement as a low-order term, even for large displacements. This expansion can be used to analyze aberrations for on-axis illumination of a high numerical aperture system.

Calculation of the volumetric diffracted field with a three-dimensional convolution: the three-dimensional angular spectrum method.

The first Rayleigh-Sommerfeld diffraction formula is treated in an exact form as a three-dimensional (3D) convolution in the spatial domain. Therefore, a 3D Fourier transform can be employed to convert the 3D diffracted electromagnetic field to the reciprocal space without approximations, which we call the 3D angular spectrum (3D-AS) method. It is also demonstrated that if evanescent waves are neglected, the 3D-AS method can be readily implemented numerically, with the results in good agreement with theoretical predictions.

One size does not fit all: the emerging frontier in large-scale marine conservation.

On the 20th anniversary of the Convention on Biological Diversity, a network of very large marine protected areas (the Big Ocean network) has emerged as a key strategy in the move to arrest marine decline and conserve some of the last remaining relatively undisturbed marine areas on the globe. Here we outline the ecological, economic and policy benefits of very large-scale MPAs and show their disproportionate value to global marine conservation targets. In particular we point out that very large-scale MPAs are a critical component of reaching the Aichi targets of protecting 10% of global marine habitats by 2020, because in addition to encompassing entire ecosystems, they will bring forward the expected date of achievement by nearly three decades (2025 as opposed to 2054).

Imaging using cylindrical vector beams in a high-numerical-aperture microscopy system.

Imaging of object structures using cylindrical vector beams in an aplanatic solid immersion lens (SIL) microscope is investigated. Based on a complete optical model of an aplanatic SIL microscope, images of some object structures using radial polarization, azimuthal polarization, and azimuthal vortex beams are simulated. Some interesting imaging effects of these object structures are observed.

Pneumococcal serotypes in adult non-invasive and invasive pneumonia in relation to child contact and child vaccination status.

Background: On a population level, pneumococcal conjugate vaccination in children has reduced the incidence of vaccine-type disease in all age groups, including older adults. Few individual level studies have been performed describing the pneumococcal serotypes associated with adult community acquired pneumonia (CAP) and quantifying associations with child contact and child vaccination status.

Methods: Pneumococcal serotypes were determined using a validated multiplex immunoassay (Bio-Plex) in a large prospective cohort of adults hospitalised with CAP.

Full-wave approach for x-ray phase imaging.

We present a rigorous forward model for phase imaging of a 3-D object illuminated by a cone-shaped x-ray beam. Our model is based on a full-wave approach valid under the first Rytov approximation, and thus can be used with large and thick objects, e.g.

Superresolution by image scanning microscopy using pixel reassignment.

The effect of detector array size on resolution and signal collection efficiency of image scanning microscopy based on pixel reassignment is studied. It is shown how the method can also be employed if there is a Stokes shift in fluorescence emission wavelength. With no Stokes shift, the width of the point spread function can be sharpened by a factor of 1.

Improvement of axial resolution and contrast in temporally focused widefield two-photon microscopy with structured light illumination.

Although temporally focused wide-field two-photon microscopy (TFM) can perform depth resolved wide field imaging, it cannot avoid the image degradation due to scattering of excitation and emission photons when imaging in a turbid medium. Further, its axial resolution is inferior to standard point-scanning two-photon microscopy. We implemented a structured light illumination for TFM and have shown that it can effectively reject the out-of-focus scattered emission photons improving image contrast.