Near-infrared images have been obtained of nine BL Lacertae objects in order to investigate their host galaxy properties. From numerical modelling of the data we find that five of the nine BL Lacs have contributions from ex-tended galaxy emission in their profiles. Tentative morphologies were derived for two of the BL Lacs, namely B2 0752 + 258, for which a disc morphology is slightly preferred, and S4 0954 + 65, for which an elliptical morphology is preferred. From our modelling we derive host galaxy absolute magnitudes of M-H = -25.6 + 0.5 for B2 0752 + 258, and M-H = -26.3 +/- 0.8 for S4 0954 + 65. We also find an average K-band absolute K-corrected host galaxy magnitude, for the BL Lacs, of [M-K]= -26.3 +/- 0.6 assuming an elliptical galaxy model, and [M-K]= -26.1 +/- 0.9 assuming a disc galaxy model. The derived absolute magnitudes are similar to those found for the putative parent population of FRI radio galaxies, predicted by unified schemes. For those BL Lacs in which host galaxies have been previously detected at optical wavelengths we derive rest frame colours which are generally consistent with those of 'normal' galaxies. However, for TEX 0836 + 182 we find a rather blue colour which, together with the elongated morphology, may be indicative of interaction or spiral structure. Our results suggest that the host galaxies of BL Lacs are indeed similar to those of FRI radio galaxies, adding further weight to the unification scenario. In our present infrared frames of relatively modest resolution, we do not find that infrared observations are any more or less effective than optical observations at revealing the underlying host galaxy.

Unified schemes for radio-loud active galaxies suggest that the different observed classes of active galactic nuclei (AGN) arise from the same basic phenomenon, with the luminosity and orientation of a relativistic jet determining the type of object seen. In the unification scheme for high-luminosity objects, optically violently variable (OVV) quasars are those systems seen end-on (i.e. down the jet), radio quasars are those seen at intermediate angles and Fanaroff-Riley type II (FR II) radio galaxies are those seen edge-on. However, the past lack of detailed information on the host galaxies of OW quasars means that it has not been possible to confirm their place within the unified scheme. In order to provide such information, we have obtained deep optical and near-infrared images of three OVV quasars. We present both one-and two-dimensional numerical modelling which has been applied to derive the parameters of the underlying galaxies.We find that the host galaxy of PKS 0736+017 is reasonably well-represented by an elliptical morphology, with total absolute K-corrected galaxy magnitudes of M-V = -21.0+/-0.1 and M-R = -22.0+/-0.2. Results from our two-dimensional modelling give an observed V - R colour of 0.8+/-0.1 for the host, consistent with the underlying galaxy being elliptical. For LB 2136, the host galaxy is resolved in our near-infrared images, but the poor sampling of the frames prevents us from determining its morphological class. Assuming an elliptical morphology we derive an absolute K-corrected magnitude of [M-K] = -27.3+/-0.6 for the host. The situation for OJ 287 is less clear, with only one of our near-infrared images clearly showing the presence of a host galaxy, from which we are unable to determine a morphological class. From this image we derive an absolute K-corrected host galaxy magnitude of M-K = -28.9+/-0.6, assuming an elliptical model. Based on model tits to our optical data, we also estimate the upper limit on the host galaxy flux to be M-R = -22.1 (assuming an elliptical model). The results for PKS 0736+017 and LB 2136 are consistent with the proposed unification schemes, as is the estimated optical magnitude of the host in OJ 287.

A longitudinal design was used to examine intellectual potential and development of analytic intelligence among Inuit children in Arctic Quebec. Children completed the board form of the Coloured Progressive Matrices (CPM) on four occasions during the first two years of formal education. Inuit children's CPM scores were consistently higher than age-appropriate U.S. norms and were comparable with data for White children in southern Quebec. In addition, the scores of children with two Inuit parents did not differ significantly from those of children with mixed Inuit/White heritage. Finally, language of instruction and teacher's ethnicity did not affect scores. In terms of the capacities measured by the CPM, Inuit children do not appear to be deficient in intellectual capacity at the time of entry into school. The factors that contribute to their academic underachievement appear to do so by preventing the learning of specific classroom materials rather than affecting their intellectual development.

BACKGROUND:Studies of mortality from asthma and chronic obstructive pulmonary disease (COPD) have relied on death certification or registration for case finding. The aim of this study was to determine the accuracy of death certification and registration in asthma and COPD.METHODS:All death certificates in Northern Ireland for 1987 where asthma or COPD (defined as International Classification of Diseases 9th Revision (ICD9) 490, 491, 492, 496) were listed in part I or part II were identified. The following certificates were then selected for further investigation: those mentioning asthma for all ages, those mentioning COPD for ages less than 56 years, and a 50% sample of those mentioning COPD aged 56-75 years. For these selected deaths the general practitioners' case notes, hospital records, and necropsy findings were reviewed. Questionnaires detailing the clinical history and circumstances of death were completed by the general practitioner by post and by a close relative or associate of the deceased (doctor administered) if, after initial investigation, the death was likely to be due to COPD or asthma. A panel of two respiratory physicians reviewed each death and, using clinical diagnostic criteria, assessed the accuracy of the registered cause of death.RESULTS:Of 50 registered asthma deaths 43 were confirmed as being due to asthma. In nine registered deaths from COPD in cases aged less than 56 years one was confirmed as COPD, two as asthma, and six as other respiratory conditions. Of 105 registered deaths from COPD in cases aged 56-75, 42 were confirmed as COPD, 27 as asthma, eight as other respiratory conditions, and 28 as other causes. Although few errors in registration were found, 21% of certificates mentioning asthma and 38% of certificates mentioning COPD but not asthma in part I were subject to variable application of the classification rules by the registering officers. For all deaths under 75 years of age in Northern Ireland in 1987 where either asthma or COPD was mentioned anywhere on the death certificate, the estimated sensitivity and specificity of the registered cause of death in predicting the "true" cause of death were 29% and 98.6% for asthma and 69% and 70% for COPD.CONCLUSIONS:In a population of subjects where asthma or COPD was mentioned anywhere on the death certificate, the registered cause of death is a relatively poor indicator of the "true" cause of death for both asthma and COPD. Variation occurred in the application of death classification rules by registration officers. Many deaths certified and registered as COPD could have been called asthma using current standards of clinical diagnosis. In studies investigating risk factors for deaths from asthma, case finding should consider deaths registered as COPD.

BACKGROUND--Asthma mortality has been rising in many western countries for largely unknown reasons. One cause could be change in certification practice. This study was designed to investigate the accuracy of death certification in Northern Ireland for the years 1981-4 and, in addition, to assess the reliability of trends observed in asthma death registration from 1957 to 1985. METHODS--The following death certificates were obtained for the years 1981-4: those mentioning asthma (all age groups), chronic obstructive airway disease, emphysema, or chronic bronchitis, but only where the decreased was 55 years or less. Information was collected from medical records, questionnaires to the general practitioner, and interviews with a close relative of the decreased. Death as a result of asthma was confirmed or otherwise by a panel and the confirmed deaths were compared with those registered. The numbers of deaths from asthma for the years 1957-85 were obtained from the offices of the Northern Ireland Registrar General. RESULTS--A total of 174 deaths from asthma was identified; 123 (70.7%) had been registered, while the remainder had been coded under another diagnosis. The annual number of confirmed deaths differed little from the figures of the Registrar General. A sharp increase in the annual number of deaths from asthma was observed, beginning in 1977, following a decline in the mid 1970s. CONCLUSIONS--During the years 1981-4 death certification for asthma was found to be inaccurate. The number of false positive registrations was balanced by the number of false negatives, suggesting that the registered totals reflect actual asthma mortality.

Polycarbonate is a polymer which is used for lightweight transparent armour in a wide range of applications. The material has an unusually high yield strain and ductility; this combined with a significant amount of strain hardening enables it to display impressive impact and perforation resistance. In this paper experimental observations are reported of penetration and perforation of polycarbonate plates by ballistic impact. Five mechanisms of deformation and subsequent fracture of the plate are identified. They are: elastic dishing, petalling, deep penetration, cone cracking and plugging. Thin plates impacted by spherical missiles exhibit elastic dishing, whereas thick plates suffer a deep penetration process. In both cases, final failure is by petalling. Cylindrical missiles impacting thick plates also cause deep penetration with final failure occurring by plugging. For thin plates impacted by cylindrical missiles, cone cracking develops from the leading edge of the missile. These process are described in detail, and the regime for each mechanism of failure is identified.

A common theme that arises from a survey of Arctic peoples around the world is the subtraction of the heritage language by the dominant "southern" language. The present research, conducted in Arctic Quebec, examined Inuit perceptions about the use of Inuttitut, French, and English for themselves, for their children at present, and for their children when they become adults. The results indicate that despite all evidence to the contrary, respondents expect continued Inuttitut vibrancy for the coming Inuit adult generation and that their children as adults will not have their Inuttitut eroded by English or by French.

Birefringent pulmonary talc granuloma are often found in lung biopsies from intravenous drug abusers (IVDA) but their clinico-pathological significance remains undefined.

An experimental and theoretical investigation has been conducted to determine the deep penetration response of polycarbonate (PC). A series of low speed deep penetration tests was performed with steel punches to establish the load versus indentation response, and to enable detailed observation of the penetration processes. The effects of nose shape, lubrication and punch diameter were determined. We found that the average pressure on the indenting end of the penetrator is equal to 4–5 times the tensile yield stress and is independent of nose shape and penetrator diameter. A hackle zone of microcracked material extends to a diameter of 1.4 times that of the penetrator, and this is surrounded by a plastic zone which extends to a diameter of 3.5 times that of the penetrator. A model of deep penetration is developed, based on the assumption that the average pressure on the nose of the penetrator equals the pressure required to expand an infinitely small circular cylindrical void to the diameter of the penetrator. The model assumes the existence of an outer elastic zone, a plastic zone and a hackle zone surrounding the penetrator. The predicted penetration pressure and the diameters of the hackle and plastic zones are reasonably accurate.

An unexpected finding that has surfaced in research on discrimination is that respondents perceive a higher level of discrimination directed at their group as a whole than at themselves as individual members of that group. The present study directly tested this personal/group discrepancy by focusing on two groups of Canadian immigrants who have been the targets of much discrimination, Haitian and South Asian women. Respondents were questioned about their personal and group discrimination on four separate dimensions: race, culture, status as newcomers to Canada, and gender Strong support was found for the generality of the personal/group discrimination discrepancy. Three possible explanations for the discrepancy point to possible avenues for future research: the denial of personal discrimination, the exaggeration of group discrimination, and information-processing biases.

The question addressed is, when do disadvantaged-group members accept their situation, take individual action, or attempt to instigate collective action? Ss attempted to move from a low-status group into an advantaged, high-status group and were asked to respond to their subsequent rejec­ tion. Ss who believed that the high-status group was open to members of their group endorsed acceptance and individual actions. When access to the high-status group was restricted, even to the point of being almost closed (tokenism), Ss still preferred individual action. Disruptive forms of collective action were only favored by Ss who were told that the high-status group was completely closed to members oftheirgroup. Ss who believed they were near togainingentry into the high-sta­ tus group favored individual protest, while Ss distant from entry were more likely to accept their position. The theoretical and societal implications ofthese findings are discussed.

Results from high strain rate tension and torsion tests have been combined with data from the literature to determine the effects of temperature, strain rate and stress state on the deformation and fracture of Polycarbonate (PC). Deformation is by shear yielding. In tension fracture is by the propagation of a single tensile microcrack. In compression and shear many tensile microcracks are nucleated; these join by plastic collapse leading to failure. There is no evidence for thermally induced localisation of deformation leading to fracture.

Resume : Les proprietes balistiques de feuilles de polycarbonate sont etudiees B I'aide d'impacts de projectiles cylindriques aux vitesses comprises entre 100 et 600 mls.La penetration se realise par expansion plastique axisymetrique, avec fissurations multiples en cdne sur la face avant du projectile.Les proprietes en cisaillement 5 haute vitesse de deformation sont mesurkes et comparees i celles du PMMA.