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The clinical assessment of patients with peripheral nerve injury is primarily dependent on subjective clinical examination. We aimed to assess whether a thermotropic liquid crystal ring (TLC-ring) could provide the basis for an objective assessment of peripheral nerve injury by detecting temperature changes in the digits innervated by the damaged nerve. A group of patients with known median, ulnar or both digital nerve injuries were compared against a control group. TLC-rings, marketed to the general public as "mood rings", were applied to the affected and unaffected digits and the colour change recorded. Areas with nerve damage showed a statistically significant difference in colour response to those without damage. This study establishes the ability of TLCs to detect cutaneous temperature changes associated with peripheral nerve injuries. Further studies and improvements are needed to refine TLC as an acute assessment tool for peripheral nerve injuries.

This study presents an assessment of the potential impacts of sea level rise on the New Jersey, USA coastal region. We produce two projections of sea level rise for the New Jersey coast over the next century and apply them to a digital elevation model to illustrate the extent to which coastal areas are susceptible to permanent inundation and episodic flooding due to storm events. We estimate future coastline displacement and its consequences based on direct inundation only, which provides a lower bound on total coastline displacement. The objective of this study is to illustrate methodologies that may prove useful to policy makers despite the large uncertainties inherent in analysis of local impacts of climate and sea level change. Our findings suggest that approximately 1% to 3% of the land area of New Jersey would be permanently inundated over the next century and coastal storms would temporarily flood low-lying areas up to 20 times more frequently. Thus, absent human adaptation, by 2100 New Jersey would experience substantial land loss and alteration of the coastal zone, causing widespread impacts on coastal development and ecosystems. Given the results, we identify future research needs and suggest that an important next step would be for policy makers to explore potential adaptation strategies.

Rapid developments in computer and information technology continue to expose new requirements for switched data services, e.g. teletext, electronic funds transfer, electronic mail. The features of packet switching make it attractive for many of these new services, and many countries, including the UK, now operate or plan to introduce public packet-switched data networks. But packet switching is a relatively new art, particularly in the realm of public-switched networks, and is itself developing rapidly, driven both by the increasing demand for switched data services and by advances in semiconductor technology. It tends therefore to be the preserve of a relatively small band of specialists. This paper reviews the principles, origins and evolution of packet switching, with particular reference to public-switched networks. The picture emerges of well laid foundations and the prospect of rapid expansion in public packet-switched networks throughout the world. The development of large switches, such as those being developed at BTRL, will play an important part in this.

For an infinite Bernoulli convolution whose support is a symmetric Cantor-type set, R. Kershner and A. Wintner [14] proved that the convolution is absolutely continuous or singular depending on whether the Lebesgue measure of the support is positive or zero respectively. Their proof employs the same construction which was developed originally by F. Hausdorff [11] in his celebrated paper, ‘Dimension und äusseres Mass’, where he introduced the notion of a fractional dimension. In this article we exploit this observation and prove a result which extends the theorem of Kershner and Wintner by considering Hausdorff instead of Lebesgue measure for the same class of infinite Bernoulli convolutions.

The ATM Forum is a key body which has been developing specifications for asynchronous transfer mode (ATM) technology over the past six years. It has produced a number of signalling specifications covering the user network interface, the inter-carrier interface and private networking environments. While work continues on ‘fine-tuning‘ these agreements, there is still discussion about how they are used in large scale networks, and in particular on the interworking of public and private network environments. This paper reviews the current status of the relevant protocols and their scope. It then explores the issues related to their interworking and discusses the role of the proposed ATM internetwork interface (AINI) as an alternative internetwork or inter-carrier interface to its broadband intercarrier interface (B-ICI).

Response of vernalization to low temperature (2°C) was studied in a winter-annual form of Lolium temulentum L., using imbibed seeds, excised mature and immature embryos, shoot apical meristems and callus tissue. Excised embryos, as early as 5 days after anthesis, and excised shoot apices could be vernalized as effectively as imbibed seeds. Cold treatment of developing embryos within the ear, however, appeared to have no vernalizing effect. Plants derived from callus by somatic embryogenesis showed varying degrees of vernalization response. The vernalization response in L. temulentum, as in winter annual cereals, appears to be located in the shoot apical meristem and the vernalized condition can be transmitted to new axillary meristems formed from it

The diagnosis of nerve injury using thermotropic liquid crystal temperature strips was compared blindly and prospectively against operative findings in 36 patients requiring surgical exploration for unilateral upper limb lacerations with suspected nerve injury. Thermotropic liquid crystal strips were applied to affected and non-affected segments in both hands in all subjects. A pilot study showed that a simple unilateral laceration without nerve injury results in a cutaneous temperature difference between limbs, but not within each limb. Thus, for detection of a nerve injury, comparison was made against the unaffected nerve distribution in the same hand. Receiver operating characteristic curve analysis showed that an absolute temperature difference ≥ 1.0°C was diagnostic of a nerve injury (area under the curve = 0.985, sensitivity = 100%, specificity = 93.8%). Thermotropic liquid crystal strip assessment is a new, reliable and objective method for the diagnosis of traumatic peripheral nerve injuries. If implemented in the acute setting, it could improve the reliability of clinical assessment and reduce the number of negative surgical explorations.

Head up tilt is an established test for assessing patients with vasovagal syncope. Prolonged asystole during the test has previously been reported in patients suffering from the malignant form of this syndrome. Little is known about the prognostic significance of this response and there is no consensus about the optimum treatment. Four such patients are reported who were treated pharmacologically. During follow up they remained free from major events and their symptoms were well controlled. Conservative management is the initial method of choice and only if this fails should implantation of a dual chamber permanent pacemaker be considered.

Systemic sclerosis is an uncommon multisystem disorder of unknown aetiology which predominantly affects the skin. Cardiac involvement, which is far more common than was originally realized, may affect any part of the heart but most frequently affects the left ventricular myocardium. Right ventricular dysfunction is usually associated with pulmonary vascular disease. We report a case of systemic sclerosis associated with right ventricular cardiomyopathy in whom pulmonary artery pressures were normal.

This chapter introduces the switching and multiplexing technology, asynchronous transfer mode (ATM), and describes how such a service should support connections-on-demand in order to evolve. It then goes on to outline the progress made in establishing a switched ATM service in Europe through the results from the JAMES project.

The interleukin-1 proteins (IL-1 alpha and IL-1 beta) are key mediators of inflammatory and immunological responses, and several in vitro and in vivo studies with protein-based antagonists have demonstrated the potential usefulness of IL-1 receptor antagonists to treat various inflammation related diseases. Based on the X-ray crystal structures of IL-1 ligands and site-directed mutagenesis data, a noncontiguous binding epitope encompassing Arg4, Phe46, Ile56, Lys93, Lys103, and Glu105 for IL-1 beta was proposed. In this paper we describe the synthesis and binding assay results of small molecule IL-1 receptor antagonists designed on the basis of the three-dimensional structure of the binding epitope. Among these, the compound 45 was found to inhibit IL-alpha binding to the Type I receptor with an IC50 value of 3 microM. A hypothesis generated using BioCad CATALYST program is also presented to rationalize these observations.

The indications for temporary pacemaker insertion are more widely documented than the complications. Awareness of the potential complications allows quicker diagnosis and may therefore be lifesaving. This article provides a practical guide to overcoming the complications of pacemaker insertion.

A subaortic membrane predisposes to bacterial endocarditis usually affecting the aortic valve and left ventricular outflow tract. Endocarditis involving the subaortic membrane itself has been described twice only; once at operation and once at postmortem. The case of a man with vegetations involving a subaortic membrane that were detected preoperatively and the echocardiographic appearances of these findings are reported.

The primary objectives have been to evaluate for different climatic conditions the role played by solar radiation in determining the accumulation of dry matter by terrestrial species and the manner in which the resulting photosynthetic products are utilized for the physiological and metabolic processes concerned with growth and development. The interacting effects of different levels of radiation and temperature on the components of growth of whole plants have been examined for a range of species from both tropical and temperate environments. These studies have been extended to include the interrelationships of density and the leaf area index on the productivity of populations of selected species. In some of these investigations the concepts of growth analysis have been combined with techniques which now permit the CO 2 fluxes within the canopy to be continuously recorded over long periods and so allow the diurnal changes in the levels of photosynthesis and respiration in the field to be directly assessed. This approach, coupled with others where similar measurements are made in a closed system, has provided much new information on the balance between gross and net photosynthetic activity. Differences in photosynthetic potential between species have been further interpreted in terms of (i) the pattern of light interception by canopies of differing structure, (ii) the component processes of photosynthesis at varying stages of development and (iii) the factors which are involved in the distribution and use of assimilates within the plant or population.

Experimental determinations of the dry liquidus temperatures of two pantellerite, and two pantelleritic trachyte glasses in the pressure range 0–2 kilobars, show minima in the liquidus curves between 0.1 and 0.2 kb. The pantellerite minima are 830°–850° C; the trachyte minima are 920°–940° C. At pressures below the minima a separate vapour phase co-exists with liquid, at higher pressures the intrinsic volatiles are completely soluble in the liquid and the liquidus curves have a positivedT/dP. Similar results have been obtained from a range of other pantelleritic glasses, and together with consistent alkali feldspar compositions (from a wide range of experimental conditions) are indicative of a close approach to equilibrium. The form of the liquidus curves above the minima, if rellecting natural conditions, offers a ready explanation of the near-or super-liquidus aspect of many peralkaline lavas. The temperatures in these anhydrous experiments are 100°–150° C higher than those for similar compositions in the presence of excess water. (Also, in the presence of excess water, the crystallization sequences in the natural glasses are profoundly modified, with pyroxene appearing on the liquidus).

Application d'un modele photothermique sur trois genotypes d'orge afin de savoir si le retard dans l'emergence des barbes a la suite de pretraitements de vernalisation represente une reponse specifique a la vernalisation

Summary Divergent selection for mesophyll cell size (mean cross-sectional area) was made within a population of ‘Veya’ perennial ryegrass. Selection for small mesophyll cells generally resulted in smaller mesophyll cells, heavier seed, and greater yield of shoot dry matter than selection for large cells. Between the third and fifth leaf stage, families from parents with small cells exhibited greater net assimilation rate and lower leaf area ratio than those from parents with large cells. Rate of light-saturated photosynthesis of young leaves was negatively related to cell size in the F1 generation. Greater shoot dry matter in the small, compared with the large, cell selections was accounted for in terms of greater initial seed reserves (heavier seed) and also greater net assimilation rate at some stage prior to full expansion of the third leaf. It was concluded that mesophyll cell size is a useful criterion for selecting for light-saturated photosynthesis in Lolium perenne.

A survey was made of the flowering responses of 47 annual, biennial and perennial grasses, to measure the extent of any winter requirement for floral induction, and to see how far this could be provided by controlled cold or short-day treatment. The annual species showed little or no inductive requirement, nor did the perennials Arrheuatherum elatius, Ceratochloa unioloides, Phleum pratense and Poa nemoralis. Most perennials possessed a definite inductive requircinent. A few species, such as Lolium perenne, responded to both cold and short-day given to the young seedling, while others, such as Phleum nodosum, Agrostis alba, A. canina, A. stolonifera and A. tenuis, responded to short-day induction but not to cold. Many temperate perennials, however, including Cynosurus cn'status, Dactylis glomerata, Festuca pratensis, F. rubra, Poa pratensis and P. trivialis did not respond to seedling induction and possibly have a juvenile stage before they are able to respond to inductive conditions. The sequence of flowering responses in the temperate perennial grasses is evidently more complex than was previously thought, and the perennial habit can be achieved by many different developmental pathways.

The importance of leaf area as a determinant of yield in herbage crops is now widely realized. Selection for a rapid increase in leaf area might therefore be a useful approach to the problem of breeding for yield. The present paper describes the seasonal changes in two important components of leaf area, rate of leaf and tiller production, in contrasting varieties of ryegrass, timothy and meadow fescue. The regular seasonal variation in these components in the glasshouse is shown to be determined primarily by available light energy, the species and varieties differing in their response to changes in light energy. The possibilities of selection for these components of leaf area are discussed, but it is pointed out that individual leaf size must also be considered.

Summary The effect of temperature during growth of ten Lolium genotypes from contrasting populations on subsequent light-saturated photosynthesis and on leaf mesophyll and stomatal characteristics was examined. Most genotypes grown at 9° and 15° C had faster rates of photosynthesis at 15° than those grown at 21° C. Photosynthetic activity at 21° C was also greater when plants were grown at 15° Compared with 21° C. This temperature effect was not associated with changes in the observed mesophyll or stomatal characteristics. Plants grown at 21° usually had smaller mesophyll cells than those grown at 15° C. Among plants grown at 9° and 15° C, and among those grown at 21° C, light-saturated photosynthesis was negatively correlated with mesophyll cell size.

Comparisons of the rate of assimilation and the anatomy of the leaves of contrasting genotypes of the grass Lolium indicate that the rate of photosynthesis at saturating light intensities depends on the thickness of the leaves and the size of the mesophyll cells.

The importance of the time and extent of head production in the herbage grasses has been realized for a long time. In bay or silage making, or in grsiss drying, it deter-mines tbe stage of maturity of the crop, and hence date of cutting, while in both hay and pasture tbe nutritive value of the herbage depends largely on the proportion of leaf and stem present. In seed production, the time of heading is of basic importance. It deter-mines date of harvesting and so may affect yield of seed.

In outbreeding species, such as perennial ryegrass, most plants are heterozygous for genes controlling agronomic characters and varieties must usually be based on more than one plant to avoid inbreeding depression. This leads to the possibility of change under the selective action of seed multiplication. Several stocks of S23 perennial ryegrass were examined to see whether such a change occurred; Irish, Kent and Hunsballe were grown for comparison. The characters recorded were date of ear emergence, winter requirement before heading, and leaf size, rate of leaf appearance, tillering and dry-weight production in the young seedling. A slight shift towards earliness of heading occurred during seed multiplication, but no regular change in the other characters could be detected. The S23 stocks could readily be distinguished from Hunsballe and, less easily, from Irish, as early as the sixth leaf stage. It is concluded that although considerable genetic variation for all these characters exists within the S23 stocks, changes during seed multiplication are not inevitable but depend on the management of the crop.

Summary The effect of leaf position, specific leaf weight and chlorophyll on light-saturated apparent photosynthesis, and their relationships with leaf mesophyll, among contrasting Lolium genotypes are described. Within a range of up to four fully expanded leaves on a tiller, the lower (older) leaves had greater photosynthetic activity than the upper (younger). For any particular leaf, maximum photosynthesis was attained prior to full expansion. These effects were closely related to differences in mesophyll cell size. A wide range in leaf chlorophyll levels exhibited by Lolium mutants was not associated with differences in apparent photosynthesis. Specific leaf weight and chlorophyll content were greater in thin leaves with small mesophyll cells than in thick leaves with large cells. Chlorophyll content was not associated with differences in photosynthesis in limiting light (500 ft-candles).

Populations of Cenchrus ciliaris differ significantly in relative growth-rate (R), net assimilation rate (E), and leaf-area ratio (F). Differences in R were related to differences in E rather than in F. The populations also differed in the rate of apparent photosynthesis of individual leaves as measured by infra-red gas analysis, Warburg and UC02 techniques. Temperature and light-response measurements revealed optimum temperature for photosynthesis of 35 °C and the rate in most populations continued to increase up to the highest levels of irradiance employed (200 W m~2). The relative order of the populations was similar in all methods of analysis, but there was no relationship evident between leaf photosynthesis and E derived from growth analysis. The activity of the enzyme PEP carboxylase, expressed in terms of unit leaf area, was correlated with photosynthetic rate of the leaf. Activities of PEP car boxylase and of protein synthesis in vitro expressed on a basis of soluble protein content were correlated with E, but no such relationship was found for the enzymes acid phosphatase and alanine a -ket oglutarat e aminotransferase.

Summary The effect of light intensity during leaf formation on subsequent light-saturated photosynthesis and its relation to mesophyll and stomatal characteristics, was examined among ten contrasting Lolium genotypes. Photosynthetic activity was recorded at three CO2 concentrations. At approximately 300 ppm CO2 and above, plants of the same mesophyll cell size grown in strong light (0.130 cal/cm2/min) of radiation in the spectral region 400–720 mμ. (1800 ft-candles) had faster rates of photosynthesis than those grown in relatively weak light (0.021 or 0.056 cal/cm2/ min). At the lowest CO2 concentration there was no effect on photosynthesis of the light intensity at which the plants were grown. The effect of light intensity was not associated with any change in mesophyll structure, but plants grown in weaker light (0.056 cal/cm2/min) had much smaller stomata than those grown in stronger light (0.130 cal/cm2/min). A slight increase in stomatal frequency at the low compared with the high light intensity did not compensate for the reduced stomatal length in terms of total pore space. Differences in apparent photosynthesis in any one light intensity, and between plants from all light intensities at the lowest CO2 concentration, were usually correlated negatively with mesophyll cell size. Effects of the light intensity at which plants were grown on subsequent photosynthesis could be explained in terms of changes in stomatal size.

The influence of temperature on photosynthesis and transpiration was studied in ten varieties of Loliurn perenne, L. multiflorum, Dactylis glomerata, and Festuca arundinacea from three climatic origins grown in three different controlled environments (15 °C, 72 W m-2 visible irradiation, 16-h photoperiod; 25 °C, 72 W m-2 visible irradiation, 16-h photoperiod; and 25 °C, 180 W m~2 visible irradiation, 16-h photoperiod) and in the glasshouse in July/August. The optimum temperature for photosynthesis was influenced primarily by growth environment; growth at low temperature (15 °C) resulted in a low optimum temperature, which differed little from variety to variety. The maximum C02-exchange rate was influenced by growth environment and by variety. Within a variety, plants grown at higher light intensity or lower temperature had a greater C02-exchange rate. Seven varieties showed a negative correlation between the optimum leaf temperature and the maximum C02-exchange rate. Activation energies for photosynthesis were influenced by growth environment only. There were marked varietal differences in the values of leaf resistances (ra+r?) obtained from transpiration data at the optimum leaf temperature for C02 exchange. In Lolium and Dactylis the Mediterranean varieties had higher leaf resistances than the Northern varieties with the maritime varieties intermediate. In general the Dactylis varieties had higher resistances than the corresponding Lolium and Festuca varieties. Only at high growth temperatures was (ra+rj) insensitive to temperature; otherwise an activation energy of about 10 kcal/mole was observed. A negative correlation was found between mean varietal diffusion resistances (ra + ri), and corresponding maximum C02-exchange rates.

summary A genetic dwarf (dd) of Lolium perenne is described. Its effect is to reduce cell elongation in the leaf blade and sheath. As a result, successive leaves on the shoot, instead of increasing in length, as in the normal plant, remain short and broad, and a small dwarf rosette is formed. The rate of leaf appearance on the main shoot is unaffected. Gibberellic acid, at a weekly dose of 1 cc. of a 50 mgm./1 solution per plant, results in increased cell elongation in the leaf blade and sheath, and brings the genetic dwarf within the normal phenotype for both leaf and inflorescence development. Although many genes are known which influence developmental patterns in flowering plants, in few cases is any information available about the possible biochemical mechanisms involved. In certain genetic dwarfs, however, evidence is accumulating that the mutant form can be brought within the normal phenotypic range by treatment with gibberellic acid, a growth-regulating substance derived from the fungus Gibberella fujikuroi (Saw) Wr. This substance increases the length of leaves and internodes in normal plants of many species (Brian et al., 1954), and Brian and Hemming (1955) report that in the pea (Pisum sativum), broad bean (Vicia faba) and French bean (Phaseolus vulgaris) the dwarf varieties show a greater response than the tall varieties, the different genotypes producing similar phenotypes after treatment. In maize, Phinney (1956) tested six non-allelic dwarf mutants and found that four of them could be converted into phenotypic ally normal plants by treatment with gibberellic acid. The present note describes a similar example of this effect on a dwarf mutant of perennial ryegrass (Lolium perenne).

Preoccupation with the policies of governments as a major theme in the history of the seventeenth and eighteenth centuries is now unfashionable with economic historians. However, masters of Oxford colleges and professors of social history can afford to be out of fashion. According to Mr Hill, ‘The Middle Ages in industry and internal trade also ended in 1641, when the central government lost its power to grant monopolies and to control the administration of poor relief. Attempts to prohibit the activities of middlemen, whether in industry or agriculture now ended…Guild regulations and the privileges of town oligarchies, long opposed by the common lawyers, became far more difficult to enforce…in the long run England's economic liberty, unique at that time in Europe, had a stimulating effect, especially noticeable after 1688 confirmed the political gains of the earlier revolution.’ Or as Professor Perkin claims '… the landed rulers of England… from the Restoration adopted the dynamic policy of laissez-faire in internal industry which Adam Smith… was to advocate in foreign trade.’ ‘Laissez-faire… was the direct consequence of the breakdown at the Civil War of the “Privy Council” system of central control.

A range of populations of cereals and herbage grasses, mainly of Lolium, Phieum and Triticum, have been tested in the greenhouse for response to lowtemperature vernalization. Leaf number before heading was used as the measure of reproductive development.A close correlation was found between the climatic or agronomic origin of each population and its response to low temperature. In the cereals, response to low temperature was found in one ecological group only, namely, the winter wheats from western Europe. In Lolium the duration of the life cycle is closely related to the response to vernalization. The annual strains, such as Westernwolths or Wimmera ryegrasses, head rapidly with little or no response, while most of the perennial strains have an obligatory requirement for low temperature. In Phieum none of the populations tested exhibits any marked response to, or requirement for, low temperature, but the rapidity of heading, as measured by leaf number, varies from strain to strain and shows a high correlation with persistency. Most of the weed species tested are short-lived annuals and show little or no response to low temperature.For each population, the local climate and farming system determine the optimum life cycle, and response to low temperature forms one important mechanism whereby such a life cycle can be attained.The value of these methods for varietal classification and identification was assessed by comparing the behaviour of the same material in two or more seasons or under two or more kinds of equipment. The type of lighting used to provide long-day or continuous illumination, and the date of sowing, have a differential effect only in Phalaris and Phleum. In the other material, while variations in sowing date produce slight differences in the leaf number, the interaction between strain and sowing date is small, and good discrimination between population samples is possible. It is important to keep the greenhouse temperature between 50 and 70° F. to avoid natural vernalization or devernalization of material. The use of probit diagrams for comparing truncated distributions is discussed.It is suggested that the methods can also be used to assess the genetic variation within populations. In the present results, the effect of the breeding system on the storage of variation is well shown. In self-fertilizing species, little or no variation is carried within lines, or, in the one case tested, between stocks of the same variety; it can, however, be carried between lines in a local population. In outbreeding species, each population carries considerable variation, both as genetic differences between individuals and in the heterozygous condition within individuals.