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SmartBasing provides fleet managers tools with which to manage their end-of-life aircraft fleets. The principles of SmartBasing include reassigning aircraft to different bases and assigning aircraft to a new mix of mission types to actively manage the remaining useful lifetime of each aircraft in a fleet. This paper employs a single case study aircraft to validate the SmartBasing approach for a dynamic strategy for aircraft retirement. The United States Air Force’s A-10 Thunderbolt II was used for validation, because it is an aging aircraft fleet that experienced a partial fleet retirement in 2013. The efficacy of the SmartBasing principles was tested using the aircraft retired in 2013 by altering usage patterns and basing locations in the years leading to the 2013 retirement. It was shown that SmartBasing would have been a valid technique for managing the A-10 fleet prior to its partial retirement. Better aircraft utilization planning could have expended more residual aircraft lifetime prior to retirement, resulting in savings of more than 1.88 full aircraft lifetimes or over 83 million USD in aircraft acquisition costs.

This paper aims to combine the Value Sensitive Design approach with more formalised QFD (Quality Function Deployment) methods for requirements engineering. As a case illustration we use a regional Dutch Electronic Out-of hours Record pilot, which is part of a nationwide roadmap towards Electronic Health Records. The combined approach aims at early phase requirements engineering and provides a high level situation analysis before proceeding to more solution oriented phases. We combine stakeholder analysis, value scenarios, QFD for multiple stakeholders and a consideration of systemic effects. The case illustrates several limits of existing approaches, pointing to an important and challenging area for future research. Advantages of the combined approach are: user centeredness, increased design decision transparency, considering not only service concepts and service processes but also systemic effects, combining moral exploration (VSD) with prioritisation and decisioning (QFD) and making innovation decisions more 'future-proof' by considering longer time horizons.

To characterize and distinguish the types of sensorineural hearing impairment (SNHI) that occur in hereditary motor and sensory neuropathy Type 1a (HMSN-1a) and hereditary neuropathy with liability to pressure palsies (HNPP), which are caused by deletion or frameshift mutation.

Meningeal carcinomatosis (MC) is an uncommon form of metastasis of solid tumors. Hearing loss as the presenting symptom of MC is very uncommon. A patient with an esophageal signet ring cell carcinoma 3 years previously presented with sudden onset of profound hearing loss affecting both ears. He had no evidence of local tumor recurrence. Brain magnetic resonance imaging (MRI) showed swelling and increased signal intensity on T2 weighted images of both acoustic nerves and the right trigeminal nerve. After gadolinium administration, enhancement of both acoustic and trigeminal nerves was seen. He later developed unsteadiness and head-movement-dependent oscillopsia due to vestibular areflexia and diplopia. At that time MRI showed leptomeningeal enhancement. MC was diagnosed, although cerebrospinal fluid cytology could not confirm that diagnosis. The patient died 16 weeks after the onset of deafness. In patients with progressive unilateral and bilateral hearing loss, meningeal carcinomatosis should be considered, especially if there is a history of previous malignancy.

The cervico-ocular reflex (COR) was elicited in 12 normal and 30 labyrinthine-defective (LD) subjects, lacking a vestibulo-ocular reflex (VOR) in the usual laboratory tests, by sinusoidal horizontal rotation of the body at 30° amplitude and frequencies of 0.1, 0.2 and 0.4 Hz. The head was fixed in space and the eyes were open in total darkness. The gain of the COR was measured by relating the maximum slow phase velocity (MSPV) of the eyes to the maximum input velocity (19, 38 or 75°/s) and by relating the cumulative eye displacement per hemicycle to the peak-to-peak amplitude of 60°. The COR gain was below 0.25 in the normal subjects. In the LD subjects, a clear COR was observed with a gain of about 0.7 (SD 0.3) at 0.1 Hz, decreasing to about 0.4 (SD 0.2) at 0.4 Hz. There was no appreciable phase lag in 11 of the LD subjects. In 17 other LD subjects, the phase lag was close to 0° at 0.1 Hz and increased to about 20–30° at 0.4 Hz. Testing 4 additional normal subjects with the special instruction to attempt fixation of the knee during trunk rotation in the dark, resulted in an enhanced COR showing many “catch-up” saccades with a gain close to unity; the smooth component was also enhanced. The pattern with catch-up saccades was different from the pattern observed in most LD subjects, which closely resembled the normal VOR elicited by sinusoidal rotation. The special instruction to attempt fixation of the knee was also given to one LD subject during stimulation at 0.2 Hz. Previously at this frequency, this subject had a smooth sinusoidal response with a gain of 0.33; after the instruction, the gain rose to a value of 0.92. The response continued to be smoothly sinusoidal during some entire hemicycles and only a few catch-up saccades occurred in other hemicycles. We conclude that: 1. The passive COR has a low gain in normal subjects and is enhanced in LD subjects. 2. The frequency behaviour of the smooth component of the enhanced passive COR suggests a low-pass system and, also in view of its phase behaviour, some involvement of the smooth pursuit system. 3. The occurrence of zero phase responses suggests that prediction may play an important part. 4. The passive COR can also be enhanced in normal subjects when given an appropriate instruction. The pattern, however, is different from that of the enhanced COR in LD subjects.

Familial congenital periodic alternating nystagmus (PAN) with presumably X-linked dominant inheritance (XLPAN) was observed in the proband and her mother. Many relatives had nystagmus by history. A pedigree was constructed with the data provided by the mother. Permission could not be obtained to contact any other relatives, but incidental medical data were obtained from elsewhere. From the pedigree it appeared that an X-linked dominant pattern of inheritance was most probable. The proband experienced symptomatic relief of oscillopsia by baclofen therapy (final dose 90 mg/day) but there was no appreciable change in the nystagmus intensity (at 120 mg/day).

Summary 40 forensic SIDS cases were found to have a significantly higher rate of serologic evidence of recent influenza A (H 3 N 2) infection than did matched controls.

Summary 84 forensic necropsy cases with a history of sudden unexpected death and where no acceptable cause of death was found at autopsy (= cases of sudden unexplained death, SUD) were found to have a significantly higher rate of influenza A (H 3 N 2) infection than did matched controls of the general population and a group of forensic necropsy cases with known cause of death (NON-SUD cases).

Summary Interstitial pneumonia caused by Herpes simplex virus type 1 (HSV-1) is a severe complication of orthotopic liver transplantation (LTX). The records of patients were reviewed who had an LTX at the age of 16 years or older between 1991 and 1994 with a mean follow-up of 21 months (range, 10 to 44 months). Six patients were included who had fever of >38°C, deterioration of arterial blood gases, radiological evidence of interstitial pneumonia and proof of HSV-1 in bronchoalveolar lavage fluid. All patients were anti-HSV-IgG positive before LTX. All patients were successfully treated with intravenous acyclovir, mechanical ventilation and reduced immunosuppression. Three patients who received cyclosporin A had a rejection which was successfully treated by switching to FK 506. Four patients were discharged in good health. One patient died 36 months after LTX of an unrelated cause. One patient died of urosepsis on postoperative day 139. Acyclovir together with mechanical ventilation and reduced immunosuppression proved to be an effective treatment for HSV-1 pneumonia following LTX.

In a series of 600 patients, 10 showed unilateral hyperactive caloric responses without a trivial explanation such as spontaneous nystagmus or directional preponderance. All 10 had unilateral weakness on the contralateral side, which was accompanied in 9 by cochlear hearing loss. It is assumed that the phenomenon of unilateral hyperreactivity in these cases can be explained by release from commissural inhibition on the basis of temporary vestibular decompensation.

The possibility of detecting cytomegalovirus (CMV) in formalin-fixed tissues by polymerase chain reaction (PCR) was evaluated in necropsies from lung tissues in a total of 24 patients who either had received organ transplants or were immunocompromised. PCR using two different pairs of primers for amplification of the major immediate early antigen of CMV was performed on fresh tissues and tissues fixed for 24, 48, and 72 h in neutral buffered formalin and compared to immunohistochemistry (IHC) and in situ hybridization (ISH). The fresh tissues of nine patients with serological evidence for acute CMV infection were all positive for CMV by PCR. After formalin fixation, the majority of the patients failed to show distinct signals with one or both pairs of primers as measured by densitometry. In contrast to this, fresh tissues of 15 patients without signs of an acute CMV infection were found either negative or weakly positive by PCR. Using IHC or ISH, positive results were observed only in five of nine and four of nine patients with acute CMV infection, respectively. These data demonstrate that, if only formalin-fixed tissue is available, PCR for CMV detection should be performed using two pairs of primers and should be supported by IHC.

Summary Intravenous polyoma virus inoculation into pregnant Wistar rats resulted in transplacental infection of the foetus, causing tumours and hydronephroses. Cyclosporin A reduced these effects significantly.

A mother and a daughter showed similar spontaneous conjugate circumductory nystagmus. There was appreciable influence only of horizontal, not of vertical gaze positions. In the mother there was no conjugate null region without nystagmus and the waveform did not become jerky. Optokinetic nystagmus, horizontal or vertical, could not be elicited and the same was true of the vestibulo-ocular reflex, although there were sensations of self-rotation during vestibular stimulation. Oscillopsia was reported only during head movements. This particular type of pendu-lar nystagmus, in which the vertical and horizontal pendular components are (90°) out of phase so that the apex of the cornea describes a circular or ellipsoidal trajectory, has not been described and recorded before in a hereditary congenital variety.

A case of thalidomide fetopathy is presented with several malformations, severe hearing loss, vestibular areflexia and horizontal gaze paresis. Smooth pursuit was possible only at low speed. Optokinetic responses were abnormal. The only clearly nystagmoidal response was elicited during monocular temporonasal stimulation of one eye.

After bilateral labyrinthectomy the maximum slow phase velocity of flash-induced nystagmus (FIN) was diminished; the flash induced after-nystagmus was always absent. Unilateral labyrinthectomy resulted in a weaker FIN response on stimulation of both eyes, but the best response was seen after contralateral stimulation. These findings are discussed in relation to reported effects of labyrinthectomy on OKN, "central nystagmus" and vestibular nuclear discharge activity.

Flash-induced nystagmus (FIN) was found more often in albino than in pigmented rabbits. Incremental and decremental phase mainly showed exponential change in SPV, but linear change was seen as well with apparent time constant of 5-40 sec. FIN was unaltered by rendering the stimulated eye akinetic. Lesioning the nucleus of the optic tract (NOT) on one side abolished FIN and OKN responses from the other side. Bilateral laby-rinthectomy led to a diminished response and after-responses were lost. Algebraic addition was shown if FIN was combined with vestibular reflex eye movements. The gain of these reflexes was enhanced. FIN may be specified as a type of nystagmus that is evoked by monocular essentially open-loop stimulation of the crossed ('subcortical') optic pathway. Direction-selective elements in the retina may play a specific role in that their predominant orientation gives rise to abduction nystagmus during on/off stimulation by flashes.

The results of ocular motor examinations in a patient surviving from a locked-in syndrome due to a pontine infarction, mainly on the right side, are presented. Optomotor and vestibular responses were tested. The postrotatory nystagmic response revealed vestibular hyperreactivity and short time constants. Internuclear ophthalmoplegia occurred on both sides. The patient presented evidence of lack of cortical optokinetic nystagmus (OKN) and preservation of subcortical OKN.

The gain in the optokinetic nystagmus reflex (OKR) of 27 labyrinthine-defective patients was compared with that of 27 subjects without any otoneurological abnormality, who were matched by age and sex. The patients without labyrinth function exhibited significantly higher OKR gains than the control subjects, especially so at higher age. The observed enhancement of OKR gain in the absence of vestibular function is ascribed to the effect of optokinetic training brought about by enhanced slippage of retinal images due to lack of an efficient vestibulo-ocular reflex.

Otoneurological and respiratory tests were performed on 32 patients after whiplash injury caused by a rear-end car collision. Oculomotor and cervico-ocular test results were generally normal. In a significantly large number of cases, the vestibulo-ocular reflex (VOR) was hyperactive (n = 17; 53%) and the respiratory test results were typical of the hyperventilation syndrome (HVS) (n = 12: 38%). Hyperactive VOR and the HVS occurred significantly more often in combination (n = 7; 22%) than could be accounted for by combined false positivity. Most of the significant findings were due to high relative frequencies in the women. The hyperactive VOR might have been the result of plastic adaptation to limited head mobility secondary to neck pain. Behavioural and emotional distress might offer alternative explanations for both the hyperactive VOR and HVS.

An 81-year-old man with persistent cortical blindness caused by bilateral temporo-occipital infarctions was followed for six months. He had no light or visual motion perception. Optokinetic stimulation did not elicit any optokinetic nystagmus (OKN), slow eye deviation responses, or circular vection, but the vestibulo-ocular reflex (VOR) was intact. Previously reported human cases of acquired cortical blindness with sufficient follow-up have shown similar features or otherwise either partial recovery of vision, OKN or slow eye deviation responses, or recovery of (subcortical?) OKN even without the recovery of vision and/or visual movement discrimination. It has been demonstrated that patients with acquired blindness due to anterior visual pathway dysfunction show the ability to generate smooth pursuit eye movements or to suppress the VOR by 'tracking' or 'fixating' their outstretched hand. Our patient was unable to do so. Preservation of subcortical OKN after ablation of the visual cortex is well-known in animal experiments (afoveate species, cat, and monkey). In monkeys, recovery of visual functions after cortical lesions seems to be be more rapid and more complete than in humans. This might be because monkeys can reorganize subcortical or extrastriate visual processing more successfully than humans and they are less reliant on cortical visual functions. For subcortical OKN in man, areas homologous to the MST and/or MT areas in the monkey are important, while for cortical OKN residual vision also seems necessary.

The correlation between velocity step (VS) and caloric response parameters was studied in a series of several hundred patients who underwent a neuro-otological examination. The VS parameters initial velocity (V in o/s), time constant (T in s) and Gesamtamplitude G (= VT in deg) were all significantly correlated with the caloric response parameters. The highest correlation coefficients were associated with G.

Significantly short vestibulo-ocular reflex (VOR) time constants were found in significant high numbers in patients with multiple sclerosis who had oculomotor dysfunction, especially when this dysfunction comprised both the smooth pursuit/optokinetic and the saccadic systems. Some time constants were in the range of 2.5-6 s, i.e. shorter than the presumed time constant of the primary afferent canal neuron. Increase in oculomotor impairment was accompanied by a decrease in time constants in some patients, whereas others showed a combined renormalization of previously disturbed oculomotor function and short time constants. Significantly high numbers of combinations of asymmetry in oculomotor dysfunction and a directional preponderance in time constant were observed, with the shorter time constant on the side of the (more severe) defect.

Flash-induced nystagmus (FIN) was elicited by monocular flicker-stimulation at 20-40 Hz. It was found more often in albino than in pigmented rabbits. Slow phase velocity (SPV) showed a gradual increase, then a steady-state level in most animals and an after-response after cessation of stimulation, incremental and decremental phase mainly showed an exponential change in SPV. Apparent time constants were in the range of 5-40 sec. Simultaneous recording of both eyes revealed greater velocity and amplitude of both phases of FIN in the stimulated eye. FIN can be specified as a type of nystagmus that is evoked by monocular essentially open-loop stimulation of the crossed ("subcortical") visual pathway. Direction-selective elements in the retina may play a specific role and their predominant orientation gives rise to nystagmus in adducting direction in the flicker-stimulated eye as if it were exposed to optokinetic stimulation in the temporonasal direction.

Antisera raised by vaccination of chickens with the H3N2 influenza virus strains A/Hong Kong/1/68 and A/Port/Chalmers/1/73 were found to contain common antigen antibody (CAA), combining with both viruses, and strain-specific antibody (SSA), combining with homologous virus only. The reaction of CAA with homologous and heterologous viruses and of SSA with homologous virus was investigated by means of equilibrium filtration. CAA was found to be antibody of higher quality than was SSA. The virus strains tested were found not to contain identical common antigenic determinants, and CAA and SSA competed for the same antigenic sites when allowed to react simultaneously with homologous virus. The kinetics of reaction of CAA and SSA with the corresponding viruses was tested by means of the photometric antibody concentration unit method. It was found that SSA and CAA of a given strain have the same specificity and that the reaction of CAA with heterologous virus is registered as heterologous antigen-antibody interaction. These findings suggest that SSA and CAA are antibodies of the same specificity but with differences in quality.

Auditory, vestibular and oculomotor function tests were performed in 14 FSHD patients (7 men, 7 women, aged 19-74 years) with autosomal dominant Facioscapulohumeral dystrophy (FSHD) due to chromosome 4q35 associated DNA rearrangements. (Cochlear) sensorineural hearing loss (SNHL) in excess of that expected for their age was found in 6 patients: in 3 at the higher frequencies and in 3 also at the lower (speech) frequencies. Brain-stem auditory evoked potentials were generally normal. Oculomotor functions were normal. Four patients showed vestibular hyperreflexia, perhaps secondary to diminished head movements. Despite the apparent genetic homogeneity of the present patients, the above-mentioned findings showed significant associations with certain families, the cases of new mutations, or a certain generation. Therefore, FSHD in our patients demonstrated clinical heterogeneity.

TO THE EDITOR. —In 1988, we described a family with vestibular areflexia and progressive hearing loss, presumably developing from the age of about 40 years onward, and caused by an autosomal dominant disorder.1 Among the family members examined in 1984, we found two affected members: the proband, aged 45 years (IV 9 on pedigree1), and his father, aged 71 years (III 16 on pedigree). All other family members examined were reported to show no abnormalities. This also concerned the then 42-year-old sister of the proband (IV 10 on pedigree1). However, her reexamination in 1989, when she was 47 years old, showed that she had also developed the disorder over the past 5 years, and revision of her examinations in 1984 made it clear that a more appropriate interpretation would have been that there were some indications of an impending dysfunction.In 1989, she returned to our department