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We report the investigations of spin wave modes of arrays of Ni and Co nanorods using Brillouin light scattering. We have revealed the significant influence of spin wave modes along the nanorod axis in contrast to infinite magnetic nanowires. Unusual optical properties featuring an inverted Stokes/anti-Stokes asymmetry of the Brillouin scattering spectra have been observed. The spectrum of spin wave modes in the nanorod array has been calculated and compared with the experiment. Experimental observations are explained in terms of a combined numerical–analytical approach taking into account both the low aspect ratio of individual magnetic nanorods and dipolar magnetic coupling between the nanorods in the array. The optical studies of spin-wave modes in nanorod metamaterials with low aspect ratio nanorods have revealed new magnetic and magneto-optical properties compared to continuous magnetic films or infinite magnetic nanowires. Such magnetic artificial materials are important class of active metamaterials needed for prospective data storage and signal processing applications.

Summary The nonlinear optical properties of gold nanorod arrays have been studied with a two-colour continuosly working (CW) pump-probe spectroscopy. The hybridization of the nanorod arrays with a nonlinear polymer (poly-3BCMU) has been investigated for the purposes of active photonic component design. The sensitivity of the plasmonic resonances of the hybrid nanostructured system to pump-induced changes in the refractive index of the polymer surroundings has been used to control the optical extinction of the array. Both reversible and non-reversible behaviour has been observed reflecting the combined effects from the third-order nonlinear response of the hybrid metallo-dielectric system and post-photopolymerization triggered reactions in the polymer.

Fructose-sorbitol (F-S) mixtures can provoke symptoms in irritable bowel syndrome (IBS) patients, and a proportion of IBS patients also have enteric hypersensitivity to distension. We hypothesized, therefore, that sugar malabsorption and fermentation to produce hydrogen gas may provoke symptoms to a greater extent in IBS patients hypersensitive to distension than in those patients without such hypersensitivity. Our aims were therefore to compare, in IBS patients, symptoms and breath hydrogen responses after F-S, on the basis of jejunal sensitivity and jejunal motor function.Fifteen female IBS patients (44 +/- 15 years) underwent, on separate occasions, 3-h breath hydrogen analyses after ingesting 10 g lactulose and 25 g fructose with 5 g sorbitol. Jejunal sensitivity and motor function were determined by balloon distension and 24-h manometry studies, respectively. Cumulative symptom scores and breath hydrogen production were analysed on the basis of the presence or absence of jejunal hypersensitivity and dysmotility.Four and seven patients had jejunal hypersensitivity for initial perception and pain, respectively. Eleven, nine, and nine patients had jejunal dysmotility for fasting phase 3, phase 2, and fed motor activity, respectively. Of the patients with symptom provocation after F-S (n = 8 within 3 h, n = 12 within 12 h) or with F-S malabsorption (n = 10), the relative proportion did not differ on the basis of the presence or absence of jejunal hypersensitivity or of motor dysfunction. Symptom scores and hydrogen production also were not different in these subgroups.Although carbohydrate malabsorption can provoke symptoms in some IBS patients, there is no consistent association between such a phenomenon and the presence of either jejunal hypersensitivity or dysmotility.

This paper describes an investigation into the dynamic characteristics of a rolling mill. Those characteristics representing limitations, to both productivity and gauge accuracy, are clearly identified with reference to results from a recently installed rolling mill. A linearized mathematical model is developed that conceptually describes these limitations. This model highlights the significance of gauge tension interactions, the second natural frequency of the mill stack dynamic system and the first natural frequency of the entry coil dynamic system.

An increasing demand for HLA-B27 typing as one of the tests used in the diagnosis of ankylosing spondylitis had led us to develop a rapid, automated, flow cytometric assay using whole blood and an HLA-B27 specific monoclonal antibody FD705. This article shows the data from 2093 samples tested during a 2 year period of routine HLA-B27 typing. 21.6% were clearly HLA-B27 positive whilst 73.2% were HLA-B27 negative, the remaining 5.2% required further testing before assignment of HLA-B27 status. Additional work was carried out on blood samples from individuals positive for the newly described subtype HLA-B2708.

Linear and nonlinear magneto-optical properties of the metamaterials based on nickel nanorod assemblies have been studied. The second-harmonic generation properties follow the effective medium description of the metamaterial as a homogeneous layer isotropic in the direction normal to the nanorod axes. Magneto-optical and nonlinear magneto-optical Kerr effects are enhanced in the vicinity of the plasmonic modes of Ni nanorods and of the photonic resonance of the metamaterial layer, while conventional (nonmagnetic) optical response does not exhibit plasmonic-related features. The observed surprisingly high sensitivity of magneto-optical and nonlinear magneto-optical responses to the metamaterial photonic modes is prospective for the diagnostics of plasmonic excitations in magnetic nanostructures and for possible applications in high density magneto-optical data storage.

Europe is currently in a state of flux, not just in political and economic terms, but also with regard to medicine. Changes in the provision of medical care have been common throughout both western and eastern Europe.1 The changes have two main determinants: the need to match limited resources to increasing health care demands, and - especially in central and eastern Europe - the search for new health care philosophies allied to new methods of financing and delivery. Within this process of change, primary medical care is of increasing importance. In many countries hospital based care has traditionally been overvalued and emphasised to the neglect of the appropriate funding and development of primary care. This has led to the inefficient use of both primary and secondary care sectors, often with a lack of proper cooperation and integration. Growing value is placed on the role of the well educated and trained generalist at the primary level. This is clear from developments in the United Kingdom, Holland, Denmark, Sweden, Finland, Spain, and Portugal. From the countries of central and eastern Europe, in which Soviet-style health systems have increasingly failed to meet patients' needs, come numerous requests for information, literature, and expertise on topics such as the principles of primary health care, the role of the family physician, education and training of general practitioners, and the development of the discipline of general practice in both academic and medicopolitical terms. General practice throughout Europe is diverse in its development, organisation, and funding. Some aspects of this diversity can be seen clearly from table I, which shows the numbers of doctors in European countries and the percentage of general practitioners. Table II indicates the considerable variety in consulting patterns by general practitioners throughout the European Union. In spite of this considerable diversity, which has …

We present an optical sensor based on plasmonic nanorod metamaterials. The sensor operates similar to well-established surface plasmon polariton sensors, but offers order-of-magnitude improvement over existing technology. Optical and biological applications are discussed.

Oesophageal intramural pseudodiverticulosis is a rare condition that presents with dysphagia. The diagnosis is usually not apparent endoscopically and careful radiological evaluation is required. Previous reports suggest a benign course with good response of dysphagia to oesophageal dilatation and complications have not been described. Two cases are reported, one in whom life threatening haemorrhage developed following dilatation, and one complicated by a retro-oesophageal collection. It is possible that oesophageal intramural pseudodiverticulosis results in an increased propensity to trauma and even perforation.

We demonstrate that the coupling between plasmonic modes of oriented metallic nanorods results in the formation of an extended (guided) plasmonic mode of the nanorod array. The electromagnetic field distribution associated to this mode is found to be concentrated between the nanorods within the assembly and propagates normally to the nanorod long axes, similar to a photonic mode waveguided by an anisotropic slab. This collective plasmonic mode determines the optical properties of nanorod assemblies and can be tuned in a wide spectral range by changing the nanorod array geometry. This geometry represents a unique opportunity for light guiding applications and manipulation at the nanoscale as well as sensing applications and development of molecular plasmonic devices.

Sperm morphological analysis was performed by 2 methods: light microscopy on Papanicolaou stained material and scanning electron microscopy. Both methods were found to have acceptably low levels of observer error and a positive correlation existed between them. Sperm morphology was analysed by both methods in 2 groups: (1) 104 proven "fertile" men, husbands of women who had just given birth and whose paternity had been proven by HLA studies with greater than 95.5% certainty; (2) 53 infertile men from primary infertile marriages in whom no female cause could be found and excluding those with azoospermia. There was no statistically significant difference in medians between the 2 groups when sperm morphology was analysed by light microscopy, but analysis by scanning electron microscopy did show a significant difference.

The optical properties of metallic nanorod arrays acting as plasmonic nanoantennas have been studied. Large area arrays consisting of bare Au nanorods of diameter and length tuneable in the range of 20--40 and $200--400\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$, respectively, and spacing of about $40--100\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ have been electrochemically fabricated using templates of anodized nanoporous aluminium oxide. We demonstrate a very strong sensitivity of their resonant optical properties to both the presence of a dielectric load (which is much smaller than the wavelength of the resonant electromagnetic radiation) and modification of the refractive index of this load. This allows us to finely tune the spectral position of the plasmonic resonance of the nanoantenna arrays throughout the visible spectral range from about $550\phantom{\rule{0.3em}{0ex}}\text{to}\phantom{\rule{0.3em}{0ex}}800\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ with a sensitivity better than $3\phantom{\rule{0.3em}{0ex}}\mathrm{\AA{}}$ per $1\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ thickness of the dielectric load. Such dielectric-loaded plasmonic nanoantenna arrays represent a type of anisotropic metallodielectric metamaterials with fully adjustable optical properties for imaging, sensing, and nonlinear optical applications.

Magneto-dielectric nano-composite (magnetic nanowire in anodic alumina) films are fabricated on silicon substrate. Kerr measurements reveal magnetic properties of the nano-composite, while the microwave measurements in the frequency band 0.2-18 GHz show relatively low dielectric losses. After a proper optimisation these nano- composite films may be used in nonreciprocal and magnetically tuned devices in silicon substrate based Multi-Chip Modules (MCM).

OBJECTIVE--To report multiple cases of recurrent seronegative arthropathy, enthesopathy, or both, occurring in a single family in the absence of the HLA-B27 tissue type, coexistent psoriasis or inflammatory bowel disease. METHODS--Three generations of one family together with their general practitioners completed a standard questionnaire. All subjects with a positive questionnaire and two randomly chosen subjects with negative questionnaires were then examined by a single observer. HLA tissue typing and standard sacroiliac radiographs were performed. RESULTS--Seven of 12 family members with a positive questionnaire had early onset oligo- or polyarthritis, enthesitis, or both, and fulfilled established criteria for spondyloarthropathy, although none had radiological evidence of sacroiliitis. The mean age at first symptom in this group was 22 years with only one individual having the first symptom over the age of 30 years. All subjects were rheumatoid factor negative. Histocompatibility studies showed a strong association with the HLA-B7 antigen. CONCLUSIONS--The observations provide further support for the existence of 9undifferentiated9 spondyloarthropathy and suggest that this can be associated with genetic factors other than HLA-B27.

T HE VALUE of the flow cytometric crossmatch (FCXM) has been demonstrated in many centres to be a highly sensitive method for the detection of IgG antibodies in the sera of pretransplant patients that have a significant effect on subsequent renal graft function.’ Since its original description in 1983, many tissue-typing laboratories now perform the FCXM in addition to cytotoxic crossmatching as a method for the selection of a suitable recipient for a transplanted kidney. In the United Kingdom there are currently 20 centres using or intending to use the FCXM for this purpose. As with all clinical assays it is important to study the reproducibility of the FCXM between different centres. Accordingly, over the last 4 years the British Society for Histocompatibility and Immunogenetics (BSHI) Flow Cytometry Special Interest Group has investigated how differences in the method of performing the FCXM techniques may influence the result reported.

The flow cytometric crossmatch is a technique that is increasingly being used by clinical transplant laboratories. In this multicenter study by the British Society for Histocompatibility and Immunogenetics Flow Cytometry Group, a series of crossmatches were carried out to determine whether different centers obtained the same results when performing the same crossmatch. There was greater than 80% agreement among participating laboratories on the results of 34/54 tests. There was no clear agreement in the remaining 20 cases. Quantitative analysis, estimating the number of cell-bound fluorescein molecules, demonstrated that differences in the criteria used by each center to define a positive crossmatch were responsible for some of the discordant results. When applied, definition of positivity based on molecules of fluorescein increased concordance from 57.5% to 81.4%. These results suggest that a criterion for the interpretation of results based on quantitative analysis of bound antibody may be more reliable than methods in current routine use.

The flow cytometric crossmatch (FCXM) has been reported to be more sensitive and capable of detecting very low levels of antibodies than the normally used complement dependent cytotoxicity test. We studied both the two colour IgG T cell FCXM and CDC-XM in 146 renal allograft recipients, 111 primary and 35 regrafts, of which 26% (29/111) of 1st and 20% (7/35) of regrafts had a positive FCXM. There was no overall correlation between the FCXM results and early graft outcome in primary renal allografts. The FCXM did not appear to have any advantage over the CDC-XM in predicting graft outcome in unsensitized first grafts. In the small number of regrafts studied, a positive FCXM was associated with a higher degree of graft failure. FCXM can exhibit false negative results if sera are used solely neat although these prozone phenomena do not influence subsequent graft outcome.

Summary— Four different methods for evaluating sperm motility were analysed for experimental error: subjective assessment of a wet film preparation, sperm velocity measured by time-lapse photography, sperm velocity measured by computer analysis and sperm migration across a nucleopore membrane. Subjective assessment of motility was found to be inaccurate, within single observer and between 2 observers. Both methods of measuring mean sperm velocity were accurate, particularly that using the computer analysis system; a high technical failure rate was found using time-lapse photography. Sperm migration across a nucleopore membrane was found to be highly inaccurate. Two groups were then analysed for the predictive value of these tests (excluding sperm migration): 104 proven fertile men and 53 infertile men. Although subjective motility was able to predict from which group the sample came at optimum cut-off with 78% accuracy, computer analysed sperm velocity could predict with overall 91% accuracy at optimum cut-off. Computer analysis of sperm velocity offers a rapid, objective and predictive assessment of sperm function.

The electro-optic response of a cell consisting of a thin layer of liquid crystal deposited onto gold nanorods embedded in thin film alumina with a transparent top electrode has been investigated. For p-polarized light incident from the liquid crystal side, the extinction peak associated with the nanorod longitudinal plasmon resonance is completely suppressed. The peak could be recovered by applying an external electric field parallel to the long axis of the nanorods. No extinction peak suppression is observed when the light was incident from the nanorod side of the cell. The effect is explained by polarization properties of liquid crystal.

Local restructuring of metallic nanorod arrays and the fabrication of metallodielectric microstructures using direct femtosecond laser writing technologies have been studied. Femtosecond laser ablation has demonstrated the possibility to create sharp boundaries (down to a single nanorod) on the nanorod array. Polymer structures on the nanorods can be used to control the resonance wavelengths and thus the effective refractive index of surface plasmons supported by the array. The structured nanorods and their polymer composites are important for applications in light guiding and the development of nonlinear optical nanodevices.

The use of aqueous chlorhexidine (CHD) for vas irrigation and the clinical application of trypan blue uptake in the study of the viability of nonmotile sperms following vasectomy were evaluated. At 6 weeks postvasectomy, 28 percent of the patients irrigated with water and only 7 percent of those irrigated with CHD showed sperms, while 59 percent of the nonirrigated group showed sperms. In all cases, the sperms were immotile. In the trypan blue studies, 31 of 61 semen samples had sperm counts of less than 1 x 10 less than 6 greater than, 87 percent of which had an absolute uptake of 100 percent. In the remaining samples with higher sperm counts, 53 percent had a mean uptake of 100 percent. The results demonstrate the spermicidal effect of aqueous CHD. It is concluded that the trypan blue uptake test is the most objective for determining the motility of sperm, short of direct test tube fertilization of ova.

Proposed engineering projects usually require assessments of their likely environmental effects, often to help determine the least harmful siting of such works. Even in cases where the projects are planned several years in advance, there is rarely sufficient time for a full predictive study of effects on the natural environment. In this paper we describe methods and report the accuracy of predictions made within a very limited time span of the effects on shorebirds of large scale partial reclamation of the Tees Estuary. We then summarize subsequent, more detailed studies on processes determining the numbers of shorebirds found at coastal sites and note how these can be used to help predictive studies elsewhere, provided that the personnel required to make the predictions are sufficiently experienced in work on coastal birds.

Of 8,390 children necropsies, 1,249 showed congenital malformations. Thirteen different malformations were recorded relatively often and are here designated as common. Of the necropsied children 914 had only one of these common malformations, and 140 more than one. A variety of less common anomalies was found in the remaining 195 necropsies. The 13 selected common malformations were analyzed statistically to establish whether there was significant clustering of them. Only five of the common malformations proved to be significantly associated. Both frequency and variability of complication differed considerably between groups of common malformations. There was an overall preponderance of males with the common anomalies but the different anomalies differed in respect to sex ratio.

Constitutional and environmental determinants of actinic skin damage, assessed by cutaneous microtopography, were evaluated in 1,216 subjects attending the 1981 Busselton Health Survey in Western Australia. Increasing age, male sex, the tendency to burn on exposure to sunlight and outdoor occupation were found to have independent predictive value for the presence of actinic skin damage. Crude positive and inverse associations of actinic skin damage with several other factors were shown to arise from confounding. Effect measures for outdoor leisure pursuits and sunscreen use were underestimated due to inverse associations of these factors with older age, and inverse associations of high-exposure outdoor activities with poor skin response to sunlight. Associations of constitutional traits typical of fair individuals and sunscreen use with the tendency to burn resulted in overestimation of effect measures. Empirical relationships of actinic skin damage with certain leisure activities and with use of sunscreens were also confounded by sex. The results indicate a need for greater attention to confounding in nonexperimental skin cancer research.

The design, construction and operation of a multiple-counter diffractometer are described. The instrument is used to measure up to five X-ray reflections from single crystals quasi-simultaneously: rates of data collection from protein crystals of 250 reflections per hour are achieved.

In specimens of semen kept at 37 degrees C sperm lose their motility and viability. If kept at 4 degrees C they retain their viability but lose their motility from so-called thermal shock. The best temperature to keep semen in order to preserve sperm motility is 20 degrees C. Loss of motility at 37 degrees C is not entirely prevented by prevention of bacterial contamination with antibiotics.Semen specimens were obtained from 42 fertile men requesting voluntary vasectomy and stored at 4, 20, and 37 degrees C. Analysis of motility, viability under oil immersion, and pH was made after 3, 6, 12, and 18 hours. When semen was kept at 20 degrees C there was negligible deterioration in motility after 12 hours. However, there was a significant (p .01) decrease in motility in semen kept at 4 or 37 degrees, the worst being at 4 degrees. In these experiments mortility could not be restored by rewarming the semen. Viability followed motility closely at 20 and 37 degrees but at 4 degrees C viability was well preserved despite loss of motility. At the higher temperatures the motionless sperms were dead but this was not the case at 4 degrees. As expected, there was more bacterial growth at higher temperatures, mainly gram-negative bacteria such as Esch. coli and Proteus although an occasional gram positive Enterococci were identified. At 37 degrees the semen became significantly acidic (p .001). To determine the effect of bacterial growth on sperm motility, the experiment was repeated with antibiotics added. None grew any organisms and there was no fall in pH, even at 37 degrees C. Sperm kept in the presence of antibiotics retained motility at 20 and 37 degrees C better than those kept without antibiotics but there was still a significant deterioration (p .01) in the samples kept at body temperature even when bacterial growth was prevented. These studies show it is better to keep a sample of semen at room temperature (20 degrees C) during the time between ejaculation and semen analysis but do not fully explain why this is so. Specimens kept at 37 degrees C lose both motility and viability. Those kept at 4 degrees lose motility from so-called thermal shock but retain viability.

Artificial insemination using husband's semen (A.I.H.) was carried out in 74 couples in most of whom the men had low sperm densities and/or a reduced sperm motility. There were 19 pregnancies (24%). The problems encountered and the reasons for failure are discussed.A method of artificial insemination with couples suffering a variety of infertile conditions (retrograde ejaculation, low sperm density, low sperm motility, sperm antibodies, and cervical ''hostility'') is presented. 19 pregnancies from 74 couples were achieved in 2 years. Where appropriate, ovulation was induced in women with clomiphene citrate. Men with low sperm densities were given clomiphene citrate 50 mg daily and/or fluoxymesterone 5 mg daily. After a good response to treatment was noted (a sperm count of more than 10 X 10(6)/ml, when motility was more than 30%, if antibodies were demonstrated in either partner, and if cervical ''hostility'' had been demonstrated), AIH was offered. Couples were asked to abstain from intercourse for 1 week before the husband produced a fresh specimen of semen on the day of insemination. Sperm samples were washed and centrifuged twice. The woman was positioned in a cystoscopic chair and the semen was injected slowly. The patient rested after insemination for about 15 minutes. 6 inseminations were performed in each case before the situation was reviewed. Failures were due to tubal obstruction which was undiagnosed, endocrine deficiencies, and cervical ''hostility.''

A prolate spheroidal field β-spectrometer is described in which the source and detector are located on the same side of the focal ring slit. The trajectories reach distances of up to 38 cm from the axis and the ring slit has a radius of 33 cm. The relation between the resolution and transmission has been measured for four source diameters. Using a scintillation detector of 1.85 cm diameter and 1 cm length, a resolution W of 1.28% at a transmission T of 1% of 4π has been found for a source of 1 cm diameter. For a 1 mm source the measured value range from W=0.4% at T=0.8% to W=1.52% at T=5.2%.

A girl had short stumpy hands and feet due to osseous dystrophy; in other respects she showed all the main and many of the minor features of Sotos' syndrome during infancy. Then she was on the 97th centile for height, but she grew to be a woman on the 10th centile. Menarche was at 12¾ years; growth in height stopped before 14½ though epiphysial fusion had not occurred; educational difficulties were still being fought at 18 years but she was well adjusted and happy.

An improved method of implementing the absorption correction procedure of Stuart & Walker [Acta Cryst. (1979), A35, 925-933] is presented. This method scales measured reflections to a partial reference data set of corrected intensities by determining, for each crystal, a transmission surface representing the relative transmission as a function of secondary beam directions. By reformulating the observational equations and by introducing eigenvalue filtering of the least-squares normal equations, the problems of correlation between parameters defining the transmission surface are reduced.

Summary— In this study we have adapted a well tried and sensitive fluorometric assay for DNA that uses m-diamino benzoic acid (DABA) for its reaction with deoxyribose which is cleaved by perchloric acid from DNA. We have confirmed that this is easily measured in human semen. The method has been used on 200 samples of semen from patients attending the Infertility Clinic and men attending before and after vasectomy to give a wide range of sperm density. The objective DNA estimation has been compared with sperm density measurement made by an experienced laboratory observer using the Makler chamber and making his observations in ignorance of the DNA estimations. There was good correlation between DNA concentration and sperm density. The experimental accuracy of the two methods was found to be comparable. The advantage of the method is its objectivity. However, its disadvantages are its cost in terms of time and material and it cannot be used to confirm post-vasectomy azoospermia because the method also measures DNA in leucocytes.

Summary— Using an albumen-filled column, it was possible to separate highly motile sperm from autoagglutinated, dead and immotile sperm, as well as from other seminal debris. Motility was increased from a mean of 45.4 to 74.3% (P

Four hypomelic children of abnormally short stature had slight intellectual defect, melanotic skin, and some facial features in common. 3 were followed to the age of 23-26 years, and they remained small and pigmented.

Summary— 64 infertile men with oligozoospermia took part in a double blind cross-over trial. Each patient received matching capsules of a placebo and arginine for periods of 12 weeks. There was no difference in the conception rates of the wives or changes in the quality of the semen during each period of treatment.

Synovial needle biopsy specimens from the knee joints of seven patients with rheumatoid arthritis (RA) were examined immunohistochemically before and after six months' treatment with either gold or penicillamine (disease modifying drugs, DMDs). There were significant reductions in the numbers of infiltrating T lymphocytes and a disproportionate fall in the numbers of lymphocytes of the helper/inducer subset when compared with those of the suppressor/cytotoxic subset. This resulted in a fall in the ratio of helper/inducer to suppressor/cytotoxic cells. The immunohistological changes correlated with improvements in erythrocyte sedimentation rate (ESR), serum immunoglobulins, visual analogue pain assessment, grip strength, and Ritchie articular index. A second group of nine patients with RA, already well established on DMD therapy, did not show similar changes after the six month period. The HLA class II antigens DR, DQ, and DP were widely expressed on lymphocytes, macrophages, and synovial lining cells of a group of patients with RA who had never received disease modifying drug therapy. After treatment there was a significant reduction in the expression of HLA-DP and DQ antigens.