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Objective: To inventory provision and features of childhood hearing screening after the newborn period (CHS), primarily in Europe. Design: From each participating country or region, experts provided information through an extensive questionnaire: implementation year, age at screening, test method, pass criteria, screening location, screener profession, and quality indicators: coverage, referral, follow-up and detection rates, supplemented by literature sources. Study sample: Forty-two European countries or regions, plus Russia, Malawi, Rwanda, India, and China. Results: CHS was performed universally with pure-tone audiometry screening (PTS) in 17 countries or regions, whereas non-universal CHS was performed in eight with PTS or whisper tests. All participating countries with universal PTS had newborn hearing screening. Coverage rate was provided from three countries, detection rate from one, and referral and follow-up rate from two. In four countries, universal PTS was performed at two ages. Earliest universal PTS was performed in a (pre)school setting by nurses (n = 9, median age: 5 years, range: 3–7), in a healthcare setting by doctors and nurses (n = 7, median age: 4.5 years, range: 4–7), or in both (n = 1). Conclusions: Within universal CHS, PTS was mostly performed at 4–6 years by nurses. Insufficient collection of data and monitoring with quality indicators impedes evaluation of screening.

Objectives: To assess the performance of newborn hearing screening (NHS) programmes, through selected quality measures and their relationship to protocol design. Design: NHS coverage, referral, follow-up and detection rates were aggregated. Referral rates were compared to age at screening step 1, number of steps, and test method: OAE or aABR. Study sample: A questionnaire on existing hearing screening was completed by experts from countries in Europe, plus Russia, Malawi, Rwanda, India and China. Results: Out of 47 countries or regions, NHS coverage rates were reported from 26, referral rates from 23, follow up from 12 and detection rates from 13. Median coverage rate for step 1 was 96%. Referral rate from step 1 was 6–22% where screening may be performed 24 h, and 4% for >72 h. Referral rates to diagnostic assessment averaged 2.1% after one to two steps using OAE only, 1.7% after two steps including aABR, and 0.8% after three to four steps including aABR. Median detection rate for bilateral permanent hearing impairment ≥40dB was 1 per 1000 infants. Conclusion: Referral rates were related to age, test method and number of screening steps. Quality measures were not available for many NHS programmes.

Newborn hearing screening (NHS) varies regarding number and type of tests, location, age, professionals and funding. We compared the provision of existing screening programmes.A questionnaire containing nine domains: demography, administration, existing screening, coverage, tests, diagnosis, treatment, cost and adverse effects, was presented to hearing screening experts. Responses were verified. Clusters were identified based on number of screening steps and use of OAE or aABR, either for all infants or for well and high-risk infants (dual-protocol).Fifty-two experts completed the questionnaire sufficiently: 40 European countries, Russia, Malawi, Rwanda, India and China.It took considerable effort to find experts for all countries with sufficient time and knowledge. Data essential for evaluation are often not collected. Infants are first screened in maternity wards in most countries. Human development index and health expenditure were high among countries with dual protocols, three screening steps, including aABR, and low among countries without NHS and countries using OAE for all infants. Nationwide implementation of NHS took 6 years, on average.The extent and complexity of NHS programmes are primarily related to health expenditure and HDI. Data collection should be improved to facilitate comparison of NHS programmes across borders.

Objectives The EUSCREEN study compares the cost-effectiveness of paediatric hearing screening programmes and aims to develop a cost-effectiveness model for this purpose. Alongside and informed by the development of the model, neonatal hearing screening (NHS) is implemented in Albania. We report on the first year. Methods An implementation plan was made addressing objectives, target population, screening protocol, screener training, screening devices, care pathways and follow up. NHS started January 1st, 2018 in four maternity hospitals: two in Tirana, one in Pogradec and one in Kukes, representing both urban and rural areas. OAE-OAE-aABR was used to screen well infants in maternity hospitals, whereas aABR-aABR was used in neonatal intensive care units and in mountainous Kukes for all infants. Screeners’ uptake and attitudes towards screening and quality of screening were assessed by distributing questionnaires and visiting the maternity hospitals. The result of screening, diagnostics, follow up and entry into early intervention were registered in a database and monitored. Results Screeners were keen to improve their skills in screening and considered NHS valuable for Albanian health care. The number of “fail” outcomes after the first screen was high initially but decreased to less than 10% after eight months. In 2018, 11,507 infants were born in the four participating maternity hospitals, 10,925 (94.9%) of whom were screened in the first step. For 486 infants the result of screening was not registered. For the first screen, ten parents declined, eight infants died and one infant was discharged before screening could be performed. In 1115 (10.2%) infants the test either could not be performed or the threshold was not reached; 361 (32,4%) of these did not attend the second screen. For the third screen 31 (34.4%) out of 90 did not attend. Reasons given were: parents declined (124), lived too far from screening location (95), their infant died (11), had other health issues (7), or was screened in private clinic (17), no reason given (138). Conclusions Implementation of NHS in Albania is feasible despite continuing challenges. Acceptance was high for the first screen. However, 32.4% of 1115 infants did not attend the second screen, after a “fail” outcome for the first test.

Rotatable retarders have been developed for applications in spectroscopic, full Mueller Matrix ellipsometry in the far-IR spectral range. Several materials, such as silicon, KRS-5, and a commercial polymer plastic (TOPAS) have been utilized to achieve a fully adjustable retardation between 0° and 90°. Experimental characteristics of the rotatable retarders that utilize three- and four-bounce designs are compared with calculations. We discuss the effect of light focusing on the performance of these rotatable retarders.

This article concerns the first stage of a research and development project that aimed to produce both parent and professional guidelines on the promotion and provision of informed choice for families with deaf children. It begins with a theoretical discussion of the problems associated with the concept of informed choice and deaf child services and then focuses specifically on why a metastudy approach was employed to address both the overcontextualized debate about informed choice when applied to deaf children and the problems associated with its investigation in practice with families and professionals. It presents a detailed analysis of the conceptual relevance of a range of identified studies "outside" the field of deafness. These are ordered according to 2 main conceptual categories and 7 subcategories - (a) the nature of information: "information that is evaluative, not just descriptive" "the difficulties of information for a purpose" "the origins and status of information" and "informed choice and knowledge, not informed choice and information" and (b) parameters and definitions of choice: "informed choice as absolute and relative concept", "preferences and presumptions of rationality", and "informed choice for whom?" Relevant deaf child literature is integrated into the discussion of each conceptual debate in order both to expand and challenge current usage of informed choice as applied to deaf children and families and to delineate possible directions in the planning of the next stage of the main project aimed at producing parent/ professional guidelines. © 2006 Oxford University Press.

We report the production of high power (20watts average, ∼ 1 Megawatt peak) broadbandTHz light based on coherent emission fromrelativistic electrons. Such sources areideal for imaging, for high power damagestudies and for studies of non-linearphenomena in this spectral range. Wedescribe the source, presenting theoreticalcalculations and their experimentalverification. For clarity we compare thissource with one based on ultrafast lasertechniques.

Infrared radiation from synchrotron storagerings serves as a high-brightness source fordiffraction-limited microspectroscopy inboth the mid- and far-infrared spectralranges. Mid-infrared absorption, due to localvibrational modes within complex molecules,is shown to be sensitive to small chemicalchanges associated with certain diseases.Farinfrared modes are believed to result from thefolding or twisting of larger, morecomplex molecules. The ability for thesynchrotron source to perform microscopy ata frequency of 1 THz is demonstrated.

Terahertz (THz) radiation, which lies in the far-infrared region, is at the interface of electronics and photonics. Narrow-band THz radiation can be produced by free-electron lasers and fast diodes. Broadband THz radiation can be produced by thermal sources and, more recently, by table-top laser-driven sources and by short electron bunches in accelerators, but so far only with low power. Here we report calculations and measurements that confirm the production of high-power broadband THz radiation from subpicosecond electron bunches in an accelerator. The average power is nearly 20 watts, several orders of magnitude higher than any existing source, which could enable various new applications. In particular, many materials have distinct absorptive and dispersive properties in this spectral range, so that THz imaging could reveal interesting features. For example, it would be possible to image the distribution of specific proteins or water in tissue, or buried metal layers in semiconductors; the present source would allow full-field, real-time capture of such images. High peak and average power THz sources are also critical in driving new nonlinear phenomena and for pump-probe studies of dynamical properties of materials.

The characteristics of topological insulators are manifested in both their surface and bulk properties, but the latter remain to be explored. Here we report bulk signatures of pressure-induced band inversion and topological phase transitions in Pb(1-x)Sn(x)Se (x=0.00, 0.15, and 0.23). The results of infrared measurements as a function of pressure indicate the closing and the reopening of the band gap as well as a maximum in the free carrier spectral weight. The enhanced density of states near the band gap in the topological phase gives rise to a steep interband absorption edge. The change of density of states also yields a maximum in the pressure dependence of the Fermi level. Thus, our conclusive results provide a consistent picture of pressure-induced topological phase transitions and highlight the bulk origin of the novel properties in topological insulators.

Synopsis Synchrotron-based infrared microscopic measurements have been performed on various hair transverse sections, sampled either from the heads of Caucasian or Afro-American subjects. Lipid content of various virgin hair transverse sections was established, with an unprecedented resolution. The variations in shape and intensity of the CH2, CH3, amide I and amide II bands, before and after lipid removal by solvent extraction, were profiled, showing clearly that Caucasian hair often contains lipids localized inside the medulla and to a lesser extent inside the cuticle. This statement does not hold for the Afro-American hair analysed. For this, the FT-IR spectra do not change within the hair section and are insensitive to solvent extraction. The importance of the origin of hair on its physical and chemical properties has to be taken into account in future investigations. Resume Par utilisation de la microscopie infra-rouge utilisant le rayonnement synchrotron, la repartition des lipides sur la section de cheveux vierges (caucasiens et afro-americains), a pu etre comparee avec une resolution spatiale jamais egalee. La forme et l'intensite des bandes CH2, CH3, amide I et amide II, avant et apres delipidation par solvants ont ete obtenues. Il apparait que pour le cheveu caucasien, les lipides sont majoritairement localises dans la medule et dans la cuticule en quantite moindre. Ceci n'est pas le cas pour les cheveux afro-americains: leur spectre infra-rouge est le meme sur toute la section et est insensible a la delipidation. L'origine des cheveux est donc particulierement importante pour l'etude de leurs proprietes physico-chimiques.

(2000). The impact of infrared synchrotron radiation in biology: Past, present and future. Synchrotron Radiation News: Vol. 13, No. 5, pp. 31-38.

The instrumentation and performance of the new infrared beamline U12IR at the National Synchrotron Light Source of Brookhaven National Laboratory is described. This beamline utilizes infrared synchrotron radiation from a bending magnet. A combination of beamline design features and spectroscopic instrumentation allows the facility to reach the extremely low frequency limit of ∼2 cm−1 (i.e., 60 GHz or a photon energy of 250 μeV). The infrared light from the synchrotron emission at U12IR is compared to standard thermal sources and reveals substantial benefits for the study of small samples. In particular, the intensity of the synchrotron radiation in the far infrared can be as much as 200 times greater than that from a blackbody when millimeter-sized samples are measured. The effects of diffraction and noise on beamline performance are also discussed.

A Bruker model IFS 125HR Fourier transform interferometer has been installed and its performance tested using high-brightness, far-infrared synchrotron radiation. Results of absorption measurements for the rotational modes of water vapor demonstrate a nearly 10-fold improvement in signal-to-noise when compared with the instrument’s internal high-pressure Hg arc lamp source.

We review the properties of infrared synchrotron radiation and particularly those of the beamlines at the NSLS, Brookhaven National Laboratory. We show how this unique, pulsed broadband source with its 1000-fold brightness advantage over thermal sources has been utilized for research programs in surface science, solid-state physics and microscopy and discuss plans for 5 new beamlines at the NSLS.

The VUV ring at the National Synchrotron Light Source (NSLS, Brookhaven national Laboratory) is a source of nanosecond-duration, high-brightness, broadband IR pulses. The authors are developing several measurement techniques for characterizing Hg1-xCdxTe and other IR detector materials using this source. For example, the broadband IR pulses can be used to study transient photoconductive decay at various photon energies near the bandgap. A particularly novel technique they have developed is far-infrared photoinduced nanosecond spectroscopy (FIR-PINS). In this all-optical (contactless) measurement, a short laser pulse generates photocarriers which are subsequently sensed by a far-infrared pulse from the synchrotron. Spectroscopic analysis of the far-infrared yields the free carrier plasma frequency, providing information on the photocarrier density. By varying the delay time of the far-infrared pulse (relative to the laser pulse), the photocarrier relaxation is determined with nanosecond resolution. In addition to being contactless, the technique offers other potential advantages over electrical measurements. Results for MBE-grown Hg1-xCdxTe are presented.

A new infrared beamline has been developed on a conventional dipole bending magnet port of the vacuum ultraviolet ring at the National Synchrotron Light Source. The port provides approximately 12 mrad horizontal and 8 mrad vertical aperture, which limits the useful spectral range to wavelengths less than 20 μm. Though the total flux across the midinfrared is less than that from a globar source, the calculated brightness is at least two orders of magnitude greater. Also, the synchrotron source delivers light in subnanosecond pulses. The developing experimental programs include studies of hydrogen and other materials at extremely high pressures, and time‐resolved studies of infrared sensor materials. The measurement results presented here, characterizing the actual brightness advantage and spectroscopic performance, demonstrate the synchrotron’s remarkable advantage for microspectroscopic studies.

A facility to perform infrared microspectroscopy is under development at the NSLS of Brookhaven National Laboratory. The high brightness infrared light produced as synchrotron radiation makes a nearly ideal source for microspectroscopy. High quality spectra from 10 μm sized areas can be acquired in less than 1 min. A description of the installation, microspectroscopy performance, and an example application are presented.

Pump–probe spectroscopy has been used to study quasiparticle dynamics in a superconducting Nb 0.5 Ti 0.5 N thin film subject to a parallel magnetic field. The broadband, time-resolved, photo-induced far-infrared transmission S ( t ) was measured and used to extract a time-dependent effective recombination rate τ eff - 1 ( t ) . We found that τ eff - 1 ( t ) decreases with increasing field. The rate τ eff - 1 ( t ) is found to scale with S ( t ) at high laser fluence.

We have measured a fast response by thin‐film YBa2Cu3O7−δ detectors to pulsed, broadband, infrared radiation. Synchrotron light from an electron storage ring was used as the infrared source, providing subnanosecond pulses from far infrared through visible. Pulse responsivities as high as 106 V/J and as fast as 4 ns have been observed. For film thicknesses in the range 400–3200 A, the detector response follows the film absorptivity while the speed varies inversely with thickness, suggesting a bolometric mechanism. Calculations based on such a model are in accord with the data. We find no evidence for any nonbolometric components in the response.

Finite-difference time-domain methods are increasingly being used to develop, model and analyze the response of materials, including engineered metamaterials that may contain superconductors. Though simple and useful expressions for the time-domain susceptibility exist for basic metals and dielectrics, the time-domain response for a superconductor has not been developed, mainly because the frequency-dependent expressions themselves are rather complex. In this paper we present a simple approximate expression for the time-domain susceptibility of a superconductor for the hbar/2Delta time scale (where Delta is the BCS energy gap) that fulfills causality requirements, and demonstrate its ability to model the transmission and reflection of a fully-gapped superconductor in the THz region. By allowing Delta to be a function of current, we also show how this model function can be used to describe nonlinear microwave response in superconductors.

Infrared synchrotron radiation is a high brightness, pulsed source that enables a variety of novel spectroscopic techniques. One of these is time-resolved, broadband spectroscopy for probing dynamical processes. At the National Synchrotron Light Source (Brookhaven) we have implemented a synchronized laser system for performing pump–probe spectroscopy of superconductors and other materials. In the case of superconductors, we use laser pulses to break Cooper pairs, producing an excess population of quasiparticles. The relaxation (recombination) of this population is then probed with synchrotron infrared pulses, and analyzed in terms of the intrinsic relaxation times for excited quasiparticles and phonons. This presentation will describe the time-resolved technique and results for various metallic and oxide superconductors.

The spatial resolution for infrared microspectroscopy is investigated to determine the practical limits imposed by diffraction or optical aberrations. Quantitative results are obtained using high brightness synchrotron radiation, which serves as a diffraction-limited infrared “point source” for the microscope. The measured resolving power is in good agreement with diffraction theory, including a ∼ 30% improvement for a confocal optical arrangement. The diffraction calculation also shows how the confocal setup leads to better image contrast. The full width at half maximum of the instrument’s resolution pattern is approximately λ/2 for this arrangement. One achieves this diffraction limit when the instrument’s apertures define a region having dimensions equal to the wavelength of interest. While commercial microspectrometers are well corrected for optical aberrations (allowing diffraction-limited results), the standard substrates used for supporting specimens introduce chromatic aberrations. An analysis of ...

Detection of submillimeter radiation between 10 and 40 cm−1 (300–1200 GHz) has been carried out with a high resistance granular NbN film (R⧠= 8440 Ω/⧠) below 6 K with evidence of Josephson‐like operation. The nonoptimized detector sensitivity and noise equivalent power at 17.5 cm−1 (525 GHz) were about 20 V/W and 5×10−8 W/Hz1/2, respectively, comparable to values obtained with granular Sn and Pb.