Recent advances in solid oxide cell technology for electrolysis.

In a world powered by intermittent renewable energy, electrolyzers will play a central role in converting electrical energy into chemical energy, thereby decoupling the production of transport fuels and chemicals from today's fossil resources and decreasing the reliance on bioenergy. Solid oxide electrolysis cells (SOECs) offer two major advantages over alternative electrolysis technologies. First, their high operating temperatures result in favorable thermodynamics and reaction kinetics, enabling unrivaled conversion efficiencies. Second, SOECs can be thermally integrated with downstream chemical syntheses, such as the production of methanol, dimethyl ether, synthetic fuels, or ammonia. SOEC technology has witnessed tremendous improvements during the past 10 to 15 years and is approaching maturity, driven by advances at the cell, stack, and system levels.

Longitudinal study of hearing impairment in children.

The aim of this study is to evaluate the frequency of progression in permanent childhood hearing impairment (PHI) and to relate potential specific factors to the eventual progression. A description is made of the true longitudinal hearing thresholds in four groups of children according to different observation periods and being part of a prospective pediatric audiological registry-based study established in 1989. At the time of data collection the registry included 1373 children born after 1/1-1970 with a PHI > 20 dB in either the right or the left ear at any pure tone frequency. The children were subdivided according to the following observation periods: 1-3 years (N=266), >3-5 years (N=148), >5-10 years (N=212) and >10 years (N=62). The differences from the first to the most recent audiometric thresholds were analysed for the right and left ears separately, at the pure tone frequencies 250, 500, 1000, 2000, 4000 and 8000 Hz, for the average of 500, 1000, 2000 and 4000 Hz, for the average of 2000 and 4000 Hz and for the average of 4000 and 8000 Hz. Those showing a progression >15 dB for the average across 500-4000 Hz were analysed for age at onset and aetiology of hearing impairment, showing that genetic factors are predominant in progressive PHI. It was also found that progression in PHI is most frequent in early childhood but found only in 5.7% after the age of 4 years.

[Neonatal ascites: meconium ileus with perforation in mucoviscidosis]. / Neonataler Aszites: Mekoniumileus mit Perforation bei Mukoviszidose.

Many conditions are known associated with neonatal ascites such as cardiac and vascular malformations, as well as malformations of the brain, kidney, lung and bone, chromosomal abnormalities, infections, fetal anemias, tumors, metabolic and maternal conditions. In 30% no reason can be found. Meconium ileus is a causal gastrointestinal abnormality. We report about a preterm infant 35 weeks of gestation with complicated meconium ileus because of mucoviscidosis.

The prevalence of Usher syndrome and other retinal dystrophy-hearing impairment associations.

The study was undertaken to procure population-based prevalence data on the various types of Usher syndrome and other retinal dystrophy-hearing impairment associations. The medical files on 646 patients with a panretinal pigmentary dystrophy aged 20-49 years derived from the Danish Retinitis Pigmentosa (RP) register were scrutinised. The data were supplemented by a prior investigation on hearing ability in a part of the study population. After exclusion of patients with possibly extrinsic causes of hearing impairments, 118 patients, including 89 cases of Usher syndrome were allocated to one of five clinically defined groups. We calculated the following prevalence rates: Usher syndrome type I: 1.5/100,000, Usher syndrome type II: 2.2/100,000, and Usher syndrome type III: 0.1/100,000 corresponding to a 2:3 ratio between Usher syndrome type I and II. The overall prevalence rate of Usher syndrome was estimated to 5/100,000 in the Danish population, devoid of genetic isolates. The material comprised 11 cases with retinal dystrophy, hearing impairment, and additional syndromic features. Finally, 18 subjects with various retinal dystrophy-hearing impairment associations without syndromic features were identified, corresponding to a prevalence rate of 0.8/100,000. This group had a significant overrepresentation of X-linked RP, including two persons harboring a mutation in the retinitis pigmentosa GTP-ase regulator (RPGR) gene.

The causes of profound hearing impairment in a school for the deaf--a longitudinal study.

The study was aimed towards an evaluation of the causes of hearing loss in children attending the School for the 'Deaf' in Copenhagen in 1993-4 in comparison to causes evaluated 10 and 40 years previously (Arnvig, 1953; Holten and Parving, 1985). The 124 children attending the school in 1993 represent 0.04% of the age-matched target population of 312,715. A more detailed evaluation of two comparable cohorts born in 1969-77 and 1979-87 demonstrates a significant increase of children attending this type of school from 0.03% to 0.05% within a 10-year period, while a comparison between 1953 and 1993 demonstrates a reduction from 0.07% to 0.04%. The longitudinal evaluation of the causes of hearing loss showed a significant increase in the frequency of congenital inherited hearing impairment from 29% (1953) through 33% (1983) to 43% (1993), whereas a significant reduction of about 17% in the frequency of acquired deafness due to chronic otitis media was found. Between 1953 and 1993 a minor reduction (2%) in post-meningitic acquired hearing impairment was found, between 1953 and 1983 there was a significant increase in prenatal infections, compared with a decrease of 6% between 1983 and 1993. It is concluded that significant changes are found both in the prevalence of children referred to the school and in the factors causing severe to profound hearing impairment in children. Continuous recording of, and improvement in, diagnostic classification is necessary to obtain preventive measures.

[Experiences with nesidioblastosis]. / Erfahrungen mit der Nesidioblastose.

Highly differentiated processes relating to insulin-generating cells of the endocrine pancreas are covered by the term of nesidioblastosis. The disease is primarily characterised by persistent hypoglycaemia, and it affects newborns and young infants. Diffuse nesidioblastosis is predominant, as compared to focal processes. So called ductulo-insular complexes are characteristic immunohistochemical manifestations. While dietary and medicamentous therapies (diazoxide) usually failed to be effective, surgical removal so far has worked better than any other approach (subtotal and total pancreatectomy). Adequate early diagnosis should be established and pancreatectomy performed even before irreversible cerebral damage is caused by glucose deficit. Operations for subtotal or total pancreatectomy were performed on five children with nesidioblastosis at the Department of Paediatric Surgery in Erfurt, over the last two years. Epilepsy continued to be manifest in one of the five. Success eventually depends on close cooperation between paediatrics and paediatric surgery.

Vestibular toxicity following netilmicin therapy in the neonatal period.

Thirty-seven children treated with netilmicin during the neonatal period were seen at follow-up at the age of 2-4 years to investigate for possible vestibular damage caused by netilmicin therapy. No definite vestibular damage could be found in these 37 patients, including three patients in whom greatly elevated serum concentrations of netilmicin had been measured. The present study confirms previous findings in adults showing a low ototoxicity of netilmicin.

Physiotherapists in ergonomics.

Recently, physiotherapy students in Denmark have been spending part of their hospital training period in a factory environment, studying working postures and work methods. It is concluded that physiotherapists so trained can provide patients with a better service and treatment through their improved knowledge of the causes of illness.