Community genetics: a bridge between clinical genetics and public health

Clinical genetics and public health differ in their subjects; in who takes the initiative; in their aims, methods and outcome measures, and therefore in their ability to handle sensitive issues. They are seemingly incompatible. Nevertheless, they can be reconciled in community genetics. Community genetics combines the best from clinical genetics and public health. It shares with clinical genetics its aim of empowerment, its methods of information and support, its outcome measures and its possibility to handle sensitive issues. It has in common with public health its subjects; the origin of its initiatives, and non-reproductive prevention. In general, communities can be defined at different levels: geographically, linguistically, socially or genetically. Genetic communities can also be defined at different levels: on the basis of common heritage, on the basis of common practice, or on the basis of common problems.     

Prediction of internal multiples

We present an asymptotic derivation of results due to Weglein et al. on the prediction of internal multiples in seismic reflection data. Our proof starts from a third-order term in the Lipmann–Schwinger–Dyson forward scattering series, which is easily interpreted as an internal multiple. In essence, we substitute the scattering potentials occurring in this term by common shot migrated data and employ stationary phase analysis to write the resulting formula in several equivalent forms, one of which is Weglein’s result. On the way, we will demonstrate that the kinematics of the prediction formulas is independent of the earth model.     

The Rapid Exfoliation and Subsequent Restacking of Layered Titanates Driven by an Acid–Base Reaction

Two‐dimensional (2D) (hydro)oxide materials, that is, nanosheets, enable the preparation of advanced 2D materials and devices. The general synthesis route of nanosheets involves exfoliating layered metal (hydro)oxide crystals. This exfoliation process is considered to be time‐consuming, hindering their industrial‐scale production. Based on in situ exfoliation studies on the protonated layered titanate H_1.07Ti_1.73O₄?H₂O (HTO), it is now shown that ion intercalation‐assisted exfoliation driven by chemical reaction provides a viable and fast route to isolated nanosheets. Contrary to the general expectation, data indicate that direct exfoliation of HTO occurs within seconds after mixing of the reactants, instead of proceeding via a swollen state as previously thought. These findings reveal that ion intercalation‐assisted exfoliation driven by chemical reaction is a promising exfoliation route for large‐scale synthesis.     

Integral resource capacity planning for inpatient care services based on bed census predictions by hour

The design and operations of inpatient care facilities are typically largely historically shaped. A better match with the changing environment is often possible, and even inevitable due to the pressure on hospital budgets. Effectively organizing inpatient care requires simultaneous consideration of several interrelated planning issues. Also, coordination with upstream departments like the operating theatre and the emergency department is much-needed. We present a generic analytical approach to predict bed census on nursing wards by hour, as a function of the Master Surgical Schedule and arrival patterns of emergency patients. Along these predictions, insight is gained on the impact of strategic (ie, case mix, care unit size, care unit partitioning), tactical (ie, allocation of operating room time, misplacement rules), and operational decisions (ie, time of admission/discharge). The method is used in the Academic Medical Center Amsterdam as a decision-support tool in a complete redesign of the inpatient care operations.     

Penultimate effects in the copolymerization of maleic anhydride with electron‐rich styrene derivatives

The (controlled) free‐radical copolymerization of maleic anhydride and styrene or derivatives thereof is often thought to provide nearly perfect alternating copolymers. Here, the RAFT copolymerization of electron‐rich styrene derivatives with maleic anhydride is reported. This copolymerization shows distinct penultimate effects, resulting in polymers with increased incorporation of styrene monomers, that is, where a tendency toward periodic (S‐S‐MA) copolymers exists. This work could be a first step towards periodic copolymers based on maleic anhydride and styrene derivatives. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2932–2939     

A facile method for the density determination of ceramic thin films using X-ray reflectivity

A fast and non-destructive method based on X-ray reflectivity was developed to determine the density of sol–gel derived ceramic thin films, without prior assumptions on the microstructure of the system. The thin film density is calculated from the critical angle θ_c, i.e. the maximum angle at which total external reflection is still observed, which becomes increasingly difficult for imperfect films. We propose a simple numerical approach, instead of laborious fitting procedures, to determine the thin film density. A pseudo-critical angle, θ_pc, was defined by the first minimum in the 3rd derivative of the reflectivity curves. The measured samples were compared with calibration curves obtained from simulations with changing film densities. Although the absolute positions of θ_c and θ_pc are different, similar shifts are observed with changing density. The accuracy of the described method was validated by determining the density of single crystal substrates (ρ_rel = 100 %) and by Rutherford backscattering spectroscopy in combination with scanning electron microscopy. Varying sample size, film thickness, and film/interface roughness of yttria-stabilized zirconia films were found to have no influence on the final calculated density.     

Biodetermination of N-(deacetyl-O-4-vinblastoyl-23)-L-tryptophan, a metabolite of vintriptol, by high-performance liquid chromatography with fluorescence detection.

The determination of N-(deacetyl-O-4-vinblastoyl-23)-L-tryptophan (vintriptol acid, VtrpA), a metabolite of the investigational semi-synthetic vinca alkaloid vintriptol [N-(deacetyl-O-4-vinblastoyl-23)-L-ethyltryptophan, VtrpE], in plasma and urine samples is described. Sample pretreatment included liquid-liquid extraction of the buffered (pH 5.0) biological samples with chloroform-2-propanol (95:5, v/v). The analyses were performed by ion-exchange high-performance liquid chromatography on normal-phase silica with fluorescence detection. The assay was applied to the analysis of samples from cancer patients who had been treated with VtrpE in a phase I clinical study. VtrpA was found to be a principal metabolite of VtrpE with up to 1.2% of the administered dose excreted in the urine.     

Beyond metric gravity: Progress on PS-200

The reconciliation of quantum mechanics and gravity on varying distance scales requires changes to General Relativity that may have testable implications. We briefly review the status of tests with matter of the inverse square law and the principle of equivalence, then report on progress on the drift-tube measurement section of PS-200, the experiment to measure the gravitational acceleration of antiprotons.     

On the determination of optical parameters for turbid materials

The radiance profile caused by illumination of a turbid medium with a pencil beam depends on the optical parameters of the sample. Measurement of this radiance profile makes it possible to find these optical parameters by comparing the radiance data to theoretical predictions. Here We determine optical parameters, viz. absorption and transport scattering coefficient s(1-g), by fitting of theoretical expressions to experimental data, and we give an indication of the area where several theoretical approaches describe the experiments correctly. The differences between the theories are discussed, and Monte Carlo calculations are used as a useful theoretical tool in the area where other (analytical) methods are not yet available.