Characterization of the displacement response in chromatic confocal microscopy with a hybrid radial basis function network

Characterization of the displacement response is critical for accurate chromatic confocal measurement. Current characterization methods usually provide a linear or polynomial relationship between the extracted peak wavelengths of the spectral signal and displacement. However, these methods are susceptible to errors in the peak extraction algorithms and errors in the selected model. In this paper, we propose a hybrid radial basis function network method to characterise the displacement response. With this method, the peak wavelength of the spectral signal is firstly extracted with a state-of-art peak extraction algorithm, following which, a higher-accuracy chromatic dispersion model is applied to determine the displacement-wavelength relationship. Lastly, a radial basis function network is optimized to provide a mapping between the spectral signals and the residual fitting errors of the chromatic dispersion model. Using experimental tests, we show that the hybrid radial basis function network method significantly improves the measurement accuracy, when compared to the existing characterizing methods.

Multidimensional Phononic Bandgaps in Three-Dimensional Lattices for Additive Manufacturing

We report on numerical modelling of three-dimensional lattice structures designed to provide phononic bandgaps. The examined lattice structures rely on two distinct mechanisms for bandgap formation: the destructive interference of elastic waves and internal resonance. Further to the effect of lattice type on the development of phononic bandgaps, we also present the effect of volume fraction, which enables the designer to control the frequency range over which the bandgaps exist. The bandgaps were identified from dispersion curves obtained using a finite element wave propagation modelling technique that provides high computational efficiency and high wave modelling accuracy. We show that lattice structures employing internal resonance can provide transmissibility reduction of longitudinal waves of up to −103 dB. Paired with the manufacturing freedom and material choice of additive manufacturing, the examined lattice structures can be tailored for use in wide-ranging applications including machine design, isolation and support platforms, metrology frames, aerospace and automobile applications, and biomedical devices.

Towards Superresolution Surface Metrology: Quantum Estimation of Angular and Axial Separations

We investigate the localization of two incoherent point sources with arbitrary angular and axial separations in the paraxial approximation. By using quantum metrology techniques, we show that a simultaneous estimation of the two separations is achievable by a single quantum measurement, with a precision saturating the ultimate limit stemming from the quantum Cramér-Rao bound. Such a precision is not degraded in the subwavelength regime, thus overcoming the traditional limitations of classical direct imaging derived from Rayleigh's criterion. Our results are qualitatively independent of the point spread function of the imaging system, and quantitatively illustrated in detail for the Gaussian instance. This analysis may have relevant applications in three-dimensional surface measurements.

Corrected parabolic fitting for height extraction in confocal microscopy

Accurate and reliable peak extraction of axial response signals plays a critical role in confocal microscopy. For axial response signal processing, nonlinear fitting algorithms, such as parabolic, Gaussian or sinc² fitting may cause significant systematic peak extraction errors. Also, existing error compensation methods require a priori knowledge of the full-width-at-half-maximum of the axial response signal, which can be difficult to obtain in practice. In this paper, we propose a generalised error compensation method for peak extraction from axial response signals. This full-width-at-half-maximum-independent method is based on a corrected parabolic fitting algorithm. With the corrected parabolic fitting algorithm, the systematic error of a parabolic fitting is characterised using a differential equation, following which, the error is estimated and compensated by solving this equation with a first-order approximation. We demonstrate, by Monte Carlo simulations and experiments with various axial response signals with symmetrical and asymmetrical forms, that the corrected parabolic fitting algorithm has significant improvements over existing algorithms in terms of peak extraction accuracy and precision.

QUALITY IMPROVEMENT: Supporting a hospital in difficulty: -experience of a '-buddying' agreement to implement a new medical pathway

Increased NHS regulation has identified many healthcare organisations with operational and/or financial difficulties. Although the causes are often complex, most cases are effectively managed internally with limited input from external agencies. How best to support the few organisations needing additional support has not been established. 'Buddying', in which senior clinical and managerial teams from a well performing organisation work with colleagues from an organisation in difficulty has been proposed as a potential solution. Previous reports suggest that these partnerships are generally valued by the organisation in difficulty but there is a paucity of measured operational benefit. In this article we present our experience of a 'buddying agreement' and its impact on the introduction of a new 'whole system' medical pathway (ie rotas, staffing, process) at an organisation in difficulty. We describe the process, problems, effect on operational performance, staff survey feedback six months post-implementation and the lessons learned.  Factors critical to success were good communication; clear responsibilities, common values and strong governance; incorporation into an effective local improvement programme; targeting of specific issues; ability to influence people and foster relationships; adequate 'manpower' and gradual transition to local 'ownership'.

Resolution enhancement for topography measurement of high-dynamic-range surfaces via image fusion

In this paper, we introduce a method and algorithm for resolution enhancement of low-resolution surface topography data by fusing them with corresponding high-resolution intensity images. This fusion is achieved by linking the three-dimensional topographical map to its intensity image via an intrinsic image-based shape-from-shading algorithm. Through computational simulation and physical experiments, the proposed method's effectiveness and repeatability have been evaluated, and the computational cost has been shown to be less than other state-of-the-art algorithms. This proposed method can be easily integrated with high-speed in-line measurements of high-dynamic-range surfaces.

Fast and cost-effective in-process defect inspection for printed electronics based on coherent optical processing

This paper presents an all-optical difference engine (AODE) sensor for detecting the defects in printed electronics produced with roll-to-roll processes. The sensor is based on the principle of coherent optical subtraction and is able to achieve high-speed inspection by minimising data post-processing. A self-comparison inspection strategy is introduced to allow defect detection by comparing the printed features and patterns that have the same nominal dimensions. In addition, potential applications of the AODE sensor in an on-the-fly pass-or-reject production control scenario are presented. A prototype AODE sensor using a digital camera is developed and demonstrated by detecting defects on several industrial printed electrical circuitry samples. The camera can be easily replaced by a low-cost photodiode to realise high-speed all-optical information processing and inspection. The developed sensor is capable of inspecting areas of 4 mm width with a resolution of the order of several micrometres, and can be duplicated in parallel to inspect larger areas without significant cost.

Perforated Duodenal Ulcer and Cigarette Smoking

Whilst the association between smoking and peptic ulceration has been reported previously, the relationship between smoking and the complications of ulcers, such as perforation, bleeding or acute painful exacerbation, has not been examined. In a retrospective study comparing 275 emergency admissions for peptic ulcer with 275 controls, cigarette smoking was significantly more common only in those with a perforated duodenal ulcer. Of 128 patients with perforated duodenal ulcers, 110 (86%) were cigarette smokers compared with 65 (51%) of the 128 matched controls (χ2, P<0.01). Cigarette smoking in patients with bleeding or acutely exacerbated ulcers was not significantly more common than in controls. These findings strongly suggest a particular association between smoking and perforated duodenal ulcer.

Effects of defocus on the transfer function of coherence scanning interferometry

Coherence scanning interferometry (CSI) offers three-dimensional (3D) measurement of surface topography with high precision and accuracy. Defocus within the interferometric objective lens, however, is commonly present in CSI measurements and reduces both the resolving power of the imaging system and the ability to measure tilted surfaces. This Letter extends the linear theory of CSI to consider the effects of defocus on the 3D transfer function and the point spread function in an otherwise ideal CSI instrument. The results are compared with measurements of these functions in a real instrument. This work provides further evidence for the validity of the linear systems theory of CSI.

High-precision lateral distortion measurement and correction in coherence scanning interferometry using an arbitrary surface

Lateral optical distortion is present in most optical imaging systems. In coherence scanning interferometry, distortion may cause field-dependent systematic errors in the measurement of surface topography. These errors become critical when high-precision surfaces, e.g. precision optics, are measured. Current calibration and correction methods for distortion require some form of calibration artefact that has a smooth local surface and a grid of high-precision manufactured features. Moreover, to ensure high accuracy and precision of the absolute and relative locations of the features of these artefacts, requires their positions to be determined using a traceable measuring instrument, e.g. a metrological atomic force microscope. Thus, the manufacturing and calibration processes for calibration artefacts are often expensive and complex. In this paper, we demonstrate for the first time the calibration and correction of optical distortion in a coherence scanning interferometer system by using an arbitrary surface that contains some deviations from flat and has some features (possibly just contamination), such that feature detection is possible. By using image processing and a self-calibration technique, a precision of a few nanometres is achieved for the distortion correction. An inexpensive metal surface, e.g. the surface of a coin, or a scratched and defected mirror, which can be easily found in a laboratory or workshop, may be used. The cost of the distortion correction with nanometre level precision is reduced to almost zero if the absolute scale is not required. Although an absolute scale is still needed to make the calibration traceable, the problem of obtaining the traceability is simplified as only a traceable measure of the distance between two arbitrary points is needed. Thus, the total cost of transferring the traceability may also be reduced significantly using the proposed method.

On tilt and curvature dependent errors and the calibration of coherence scanning interferometry

Although coherence scanning interferometry (CSI) is capable of measuring surface topography with sub-nanometre precision, it is well known that the performance of measuring instruments depends strongly on the local tilt and curvature of the sample surface. Based on 3D linear systems theory, however, a recent analysis of fringe generation in CSI provides a method to characterize the performance of surface measuring instruments and offers considerable insight into the origins of these errors. Furthermore, from the measurement of a precision sphere, a process to calibrate and partially correct instruments has been proposed. This paper presents, for the first time, a critical look at the calibration and correction process. Computational techniques are used to investigate the effects of radius error and measurement noise introduced during the calibration process for the measurement of spherical and sinusoidal profiles. Care is taken to illustrate the residual tilt and curvature dependent errors in a manner that will allow users to estimate measurement uncertainty. It is shown that by calibrating the instrument correctly and using appropriate methods to extract phase from the resulting fringes (such as frequency domain analysis), CSI is capable of measuring the topography of surfaces with varying tilt with sub-nanometre accuracy.

MTA3 Regulates Extravillous Trophoblast Invasion Through NuRD Complex

Extravillous trophoblast (EVT) invasion is required for remodeling uterine tertiary arteries and placenta development during pregnancy. Compromised EVT invasion may contribute to the pathology of placenta-related diseases. Metastasis -associated protein 3 (MTA3) is one of the subunits of nucleosome remodeling and deacetylation (NuRD) complex that represses transcription in a histone deacetylase-dependent manner. MTA3 is reported to be down-regulated in preeclamptic placentas, suggesting its potential role in EVT invasion. Here, we investigate the role of MTA3 in EVT invasion by studying its molecular mechanisms in EVT cells. First, we confirmed MTA3 expression in the EVT cells in human placenta using immunohistochemistry. We then used lentivirus-mediated MTA3 short hairpin RNA (shRNA) to knock down MTA3 expression in EVT-derived HTR8/SVneo cells and found higher invasion capacity in MTA3 knockdown cells. Using quantitative real-time PCR, we showed higher expression of invasion-related genes matrix metalloproteinase 2 (MMP2), matrix metalloproteinase 9 (MMP9), and transcription factor Snail in MTA3 knockdown compared with control cells. Co-immunoprecipitation-Western blot assay showed the protein-protein interaction of histone deacetylase 1 (HDAC1), a subunit of NuRD, with MTA3 in HTR8/SVneo cells. Co-immunoprecipitation-Mass spectrometry assay further identified 71 proteins interacting with MTA3, including NuRD subunits, heterochromatin proteins, epigenetics modifiers and transcription factors. This result not only indicated the involvement of NuRD complex in MTA3’s function, but also demonstrated the complicated multiple co-players in MTA3 and NuRD complex mediated transcription repression in EVT. In summary, our data demonstrates that MTA3 regulates EVT invasion and related gene expression via NuRD complex in EVT.

High-dose interleukin2 - a 10-year single-site experience in the treatment of metastatic renal cell carcinoma: careful selection of patients gives an excellent outcome

Background

VEGF-targeted therapy has become the mainstay of treatment for majority of mRCC patients. For most patients, benefit is short-lived and therefore treatment remains palliative in intent. HD IL2 is an effective immunotherapy treatment capable of durable remission in some patients but its unselected use has been difficult due to its modest response rate and considerable adverse effects. Using set pathology criteria as a selection tool in clinical practice, we have been able to show improved outcomes in our previous report. Here, we present an updated and extended report of this treatment and seek to explore any pathological, clinical and treatment variables likely to predict better outcomes.

Methods

This is an extension of a previously reported clinical audit, which includes mRCC cases treated with HD IL2 between 2003 and 2013. Since 2006, tumour specimens of potential candidates were routinely reviewed prospectively and stratified into Favourable or Other categories based on constitution of histological growth pattern, namely alveolar or solid versus papillary and/or sarcomatoid architecture; clear cell versus granular cell cytoplasmic morphology. HD IL2 was preferentially offered to patients with Favourable pathology. Outcome evaluation includes response rates, survival, and treatment tolerance. Multivariate analysis was performed to explore potential prognostic and predictive factors.

Results

Among prospectively selected patients with Favourable pathology (n = 106), overall response rate was 48.1 % (51/106) with CR rate of 21.6 % (23/106). Median OS was 58.1 months. Factors associated with significantly better response and/or survival includes favourable pathology pattern, higher cycle 1 tolerance and lower number of metastatic organ sites (<3). CAIX (Carbonic anhydrase 9) has prognostic value but is not predictive of response. Toxicities were those expected of IL2 but were manageable on general medical wards, with no treatment-related death. Importantly most complete responses were durable with 76 % (23/30) cases remained relapse-free (median 39 months follow up) and 2 of the seven who relapsed had had long-term disease free survival after resection of oligometastatic relapse.

Conclusions

Our experience shows that HD IL2 remains an effective and safe treatment in well-selected cases of mRCC. The result in this single-institution patient series confirms similar outcomes to our previously reported retrospective series. Given the prospect of long-term remission, fit patients with Favourable histology and low disease burden should be considered for HD IL2 in an experienced centre. Better understanding has been gained from this in-depth analysis especially the examination of possible response predictors and strategies that can improve treatment outcome.

Electronic supplementary material

The online version of this article (doi:10.1186/s40425-016-0174-5) contains supplementary material, which is available to authorized users.

Interventions that cause weight loss and the impact on cardiovascular risk factors: a systematic review and meta-analysis

Overweight and obesity increase the risks of diabetes and cardiovascular disease (CVD). This has been shown to be reversed with weight loss. A systematic review and meta-analysis were performed to determine the effect of weight loss in the primary prevention of CVD. PubMed, Embase and the Cochrane Library databases were searched electronically through to May 2013. Randomized controlled trials assessing weight loss and cardiovascular risk factors and outcomes were included. A random effects meta-analysis, with sub-group analyses for degree of weight loss, and age were performed. Because few studies reported clinical outcomes of CVD, analyses were limited to cardiovascular risk factors (83 studies). Interventions that caused any weight loss significantly reduced systolic blood pressure (-2.68 mmHg, 95% CI -3.37, -2.11), diastolic blood pressure (-1.34 mmHg, 95% CI -1.71, -0.97), low-density lipoprotein cholesterol (-0.20 mmol L(-1) , 95% CI -0.29, -0.10), triglycerides (-0.13 mmol L(-1) , 95% CI -0.22, -0.03), fasting plasma glucose (-0.32 mmol L(-1) , 95% CI -0.43, -0.22) and haemoglobin A1c(-0.40%, 95% CI -0.52, -0.28) over 6-12 months. Significant changes remained after 2 years for several risk factors. Similar results were seen in sub-group analyses. Interventions that cause weight loss are effective at improving cardiovascular risk factors at least for 2 years. © 2016 World Obesity.

Facial trauma

Facial trauma. Patients with facial trauma must be assessed in a systematic way so as to avoid missing any injury. Severe and disfiguring facial injuries can be distracting. However, clinicians must first focus on the basics of trauma care, following the Advanced Trauma Life Support (ATLS) system of care. Maxillofacial trauma occurs in a significant number of severely injured patients. Life- and sight-threatening injuries must be excluded during the primary and secondary surveys. Special attention must be paid to sight-threatening injuries in stabilized patients through early referral to an appropriate specialist or the early initiation of emergency care treatment. The gold standard for the radiographic evaluation of facial injuries is computed tomography (CT) imaging. Nasal fractures are the most frequent isolated facial fractures. Isolated nasal fractures are principally diagnosed through history and clinical examination. Closed reduction is the most frequently performed treatment for isolated nasal fractures, with a fractured nasal septum as a predictor of failure. Ear, nose and throat surgeons, maxillofacial surgeons and ophthalmologists must all develop an adequate treatment plan for patients with complex maxillofacial trauma.

Complex intubation, cricothyrotomy and tracheotomy

Complex intubation, cricothyrotomy and tracheotomy. Successful management of a difficult airway begins with recognizing the potential problem. When the patient cannot breathe spontaneously, oxygenation and ventilation should start first with bag-valve ventilation, with or without an airway adjunct such as a Mayo cannula, followed by an orotrache4l intubation attempt, performed by an experienced emergency doctor. If orotracheal intubation fails, a quick decision must be made regarding surgical options. In a "cannot intubate, cannot ventilate" situation, a surgical cricothyrotomy should be considered. When orotracheal intubation is impossible, but bag-valve or laryngeal mask ventilation is possible, an urgent surgical tracheostomy should be performed. In the long run, patients in need of longterm artificial ventilation will need a percutaneous or open tracheostomy. This review provides an update of all aspects of immediate and long-term airway management.

Face and neck: airway and sensorial capacities

Face and neck: airway and sensorial capacities. For the assessment and the management of face and neck trauma knowledge of the neuro-anatomy and physiology of the ear, nose, throat (ENT) and head and neck (HN) region and structures is essential, as this area is particularly vulnerable to injury. Indeed, the complex anatomy and physiology in this specific area supports important basic functions. In addition, this review elaborates on upper airway and sensorial capacities. Upper airway dimensions are influenced by bony and soft tissues. Age is of fundamental importance in the upper airway assessment, as significant differences in size and proportions apply in children and adults. The cranial nerves (CN) supply motor, sensory ad special sensory fibres to the upper airway. Injury of the CN is a frequent complication of trauma.

Long working distance microscope with a low obscuration aspherical Schwarzschild objective

For fine stitching of multiwindow wide-spectrum detectors, an aspherical Schwarzschild objective with an effective working distance of 525 mm has been realized for chromatic aberration-free imaging in 400-900 nm wavelength range and with a numerical aperture of 0.13. A theoretical approach for analytical design of an initial configuration has been modeled using an on-axis Taylor series expansion, and the beam obscuration ratio (OR) has been controlled down to 4%. In comparison against the theoretical spherical-based Schwarzschild objective, 77.5% of the OR has been reduced for improved contrast.