bluuebunny/crossref_metadata_2025 huggingface dataset:
Men with learning disabilities who have sex with men in public places: mapping the needs of services and users in South East London
Authors: Cambridge P.
Published: May 2006

This survey investigated the prevalence of men with learning disabilities who have sex with men in public places in three south east London boroughs. The work was administered through contact with providers of services for people with leaming disabilities and was commissioned by the local health authority. It represents the first example of needs assessment work on this theme. Service responses to risk assessment and risk management in relation to HIV and the sexual behaviour of male service users were explored. The survey identified 13 services where this was a management or practice issue, and 16 and 18 men for whom this behaviour definitely or possibly applied. This paper reports the findings of the survey and identifies issues relevant to commissioning and providing services for people with learning disabilities.
Time‐based lag sequential analysis and the functional assessment of challenging behavior
Authors: Emerson E. , Reeves D. , Thompson S. , Henderson D. , Robertson J. , Howard D.
Published: May 2006

This paper describes the application of time–based lag sequential analysis to the functional assessment of challenging behaviours shown by people with severe learning disabilities. The potential uses of the approach are illustrated with regards to identifying: (1) aspects of the stimulus control of challenging behaviour; (2) antecedents to the occurrence of challenging behaviour; and (3) the environmental consequences of challenging behaviour. The uses and limitations of the approach are discussed.
Maturity and adherence in adolescent and young adult heart recipients
Authors: Stilley Carol S. , Lawrence Kathy , Bender Ann , Olshansky Ellen , Webber Steven A. , Dew Mary Amanda
Published: May 2006

Abstract: Background: Pediatric transplant (txp) teams note high rates of non‐adherence and risky behaviors linked to morbidity and mortality among adolescent and young adult recipients. Clinicians and parents alike report symptoms of social immaturity and failure to appreciate consequences of risky behavior; relationships between the two have not been studied in this population.

Method: This two‐phase mixed method study examined adherence, high‐risk behaviors, and maturity in a sample of 27 heart recipients, aged 15–31, who underwent transplantation in childhood or adolescence at Children's Hospital of Pittsburgh. All subjects completed a projective ego development measure and a questionnaire about adherence to the post‐txp regimen. Nine recipients, purposely selected for good or poor adherence according to criteria determined by the transplant team and matched on age, participated in phase 2 qualitative interviews and mood assessments.

Results: Sixty‐three percent of the phase 1 sample missed medications, 67% missed appointments, 11% smoked, 37% had difficulty with diet, 89% exercised infrequently, 33% had tattoos, 26% had more than two body piercings, and 11% used street drugs. Six themes and a core construct of maturity were identified with qualitative methodology. Poor adherers were less mature on every theme and consistently scored at a less mature level on the projective measure of ego development. Chronological age was not related to the level of maturity in qualitative or projective data. Most interview subjects reported high levels of anxiety, and two reported clinically significant levels of depression and anger; mood was not related to adherence.

Conclusions: Non‐adherence and high‐risk behaviors are prevalent among adolescent and young adult heart recipients. Level of maturity appears to be associated with ability to adhere to the treatment regimen and avoid high‐risk behaviors.
Liver transplant in a four‐month‐old child with biliary atresia, unilateral pulmonary agenesis, and diaphragmatic hernia: First case report
Authors: Heffron Thomas , Welch David , Pillen Todd , Guy Mark , Asolati Massimo , Hagedorn Phil , Atkinson George , Fasola Carlos , Romero Rene
Published: May 2006

Abstract:  Bilateral pulmonary agenesis (PA) is a rare embryological defect incompatible with life. Unilateral PA has a wide range of clinical presentations: its prognosis depends on the presence and severity of other associated anomalies. Fetal biliary atresia has been associated with a number of congenital anomalies, but the etiology is still not understood. An unusual case of a child with right PA, right diaphragmatic hernia, and delayed diagnosed biliary atresia leading to liver failure is presented herein. At the age of 4 months the patient was referred to the Transplant Department at Children Healthcare of Atlanta at Egleston with cholestasis and failure to thrive. With a rapidly progressive liver insufficiency, this child was evaluated for liver transplantation. In the absence of any respiratory symptom, the patient received a deceased donor size‐matched left lateral segment liver transplant, which covered the diaphragmatic defect, with no further repair required. Twenty‐seven months post‐transplant, the patient has good graft function, a normal Z‐score and is thriving. In spite of the increased physiological and surgical challenges (absence of right lung tissue, hemi‐diaphragm, and ectopic position of the liver in the right chest), liver transplantation was performed with positive outcome in this high‐risk child. Whether PA, may have developmentally contributed to expression of biliary atresia will need further investigation.
Immunosuppression in infants with short bowel syndrome undergoing isolated liver transplantation
Authors: Olio Dominic Dell , Gupte Girish , Sharif Khalid , Murphy M. S. , Lloyd Carla , McKiernan Patrick J. , Kelly Deirdre A. , Beath Susan V.
Published: May 2006

Abstract: Background: Little data exist on immunosuppressive drug absorption in children with short bowel syndrome and intestinal failure associated liver disease (SBS‐IFALD).

Aim: To evaluate the absorption of immunosuppressive medications in children with SBS‐IFALD undergoing isolated liver transplantation (iLTx).

Methods: A retrospective review was performed in children with SBS‐IFALD undergoing LTx and comparison made with weight, age‐matched children undergoing iLTX (extra‐hepatic biliary atresia (EHBA) and normal intestinal length and function).

Results: Seven children with SBS‐IFALD undergoing iLTx (median residual bowel length, 60 cm, range 40–80) were compared with 15 children undergoing LTx for EHBA. SBS‐IFALD children had significantly lower trough tacrolimus levels at three months (5.8 vs. 7.9 ng/mL, p<0.05) and six months (5.0 vs. 8.0 ng/mL, p<0.05), but equivalent levels at 12 months after iLTx. The median calculated dose‐normalized concentrations indicated that systemic availability of tacrolimus was comparable in two groups at 3, 6, 12 months (33.1 vs. 23.3; 42.4 vs. 36; 51 vs. 52.9) despite the differences in enteral function. The incidence of acute rejection was 1/7 (SBS‐IFALD) and 10/15 (EHBA) group (p = 0.06).

Conclusion: Children with SBS‐IFALD demonstrated adequate absorption of oral tacrolimus without significant acute rejection rate after iLTx suggesting that modification of immunosuppression is not necessary.
External beam radiotherapy to treat intra‐ and extra‐hepatic dissemination of hepatocellular carcinoma after radiofrequency thermal ablation
Authors: Yamashita Hideomi , Nakagawa Keiichi , Shiraishi Kenshiro , Tago Masao , Igaki Hiroshi , Nakamura Naoki , Sasano Nakashi , Shiina Shuichiro , Omata Masao , Ohtomo Kuni
Published: May 2006

Background:  Radiofrequency ablation (RFA) is an alternative to percutaneous ethanol injection therapy (PEIT) for single non‐surgical hepatocellular carcinoma. However, the risk of seeding along the needle track has been reported.

Methods:  Seven patients presenting with neoplastic seeding after RFA or PEIT were treated with external beam radiotherapy using conventional fractionation. All patients underwent irradiation with a total dose in the range of 44–61 Gy (median and mode value: 50 Gy).

Results:  An objective response to treatment was achieved in six of seven patients (86%). A complete response was obtained in two patients (29%). The median survival time was 14.7 months and the actuarial 1‐ and 2‐year survivals were 67% and 50%, respectively.

Conclusions:  The response to treatment was relatively good without serious complications. Seeding from hepatocellular carcinoma is sensitive to external beam radiotherapy. It is useful in the treatment of these patients with 50 Gy in 25 fractions.
Role of the endothelium on vasoactive agents in patients with liver cirrhosis
Authors: Battaglia Samuel , Angus Peter , Chin‐Dusting Jaye PF
Published: May 2006

Background and Aim:  Patients with liver cirrhosis exhibit peripheral vasodilatation and decreased vasoconstrictor responsiveness. We investigated the role of the endothelium in these patients.

Methods:  Nine patients with cirrhosis and seven controls were recruited. Responses to acetylcholine, bradykinin and sodium nitroprusside were obtained using forearm plethysmography. Responses to norepinephrine (100 ng/min) were obtained in the absence and combined presence of the cyclo‐oxygenase inhibitor, indomethacin, and the nitric oxide (NO) synthase inhibitor, NG‐monomethyl‐L‐arginine.

Results:  Responses to acetylcholine (area under curve: controls vs cirrhotic, 10326 ± 1400 vs 18490 ± 2787 units; P = 0.036), but not to bradykinin (15619 ± 3557 vs 12415 ± 3823 units) or sodium nitroprusside, were significantly higher in patients with cirrhosis. Responses to norepinephrine were significantly dampened in cirrhotics (percentage increase in forearm blood flow; controls vs cirrhotics, −50.50 ± 2.69 vs−26.39 ± 5.44; P = 0.036) but this blunted response was no longer apparent following the administration of both blockers.

Conclusions:  We conclude that: (i) there is an increased response to acetylcholine but not to bradykinin; and (ii) that an enhanced production of prostacyclin and/or NO is responsible for the dampened response to norepinephrine.
On the Distance Between Cumulative Sum Diagram and Its Greatest Convex Minorant for Unequally Spaced Design Points
Authors: PAL JAYANTA KUMAR , WOODROOFE MICHAEL
Published: May 2006

Abstract.  The supremum difference between the cumulative sum diagram, and its greatest convex minorant (GCM), in case of non‐parametric isotonic regression is considered. When the regression function is strictly increasing, and the design points are unequally spaced, but approximate a positive density in even a slow rate (n−1/3), then the difference is shown to shrink in a very rapid (close to n−2/3) rate. The result is analogous to the corresponding result in case of a monotone density estimation established by Kiefer and Wolfowitz, but uses entirely different representation. The limit distribution of the GCM as a process on the unit interval is obtained when the design variables are i.i.d. with a positive density. Finally, a pointwise asymptotic normality result is proved for the smooth monotone estimator, obtained by the convolution of a kernel with the classical monotone estimator.
Computations via Auxiliary Random Functions for Survival Models
Authors: LAUD PURUSHOTTAM W. , DAMIEN PAUL , WALKER STEPHEN G.
Published: May 2006

Abstract. A new simulation method,auxiliary random functionsis introduced. When used within a Gibbs sampler, this method enables a unified treatment of exact, right‐censored, left‐censored, left‐truncated and interval censored data, with and without covariates in survival models. The models and methods are exemplified via illustrative analysis.
Semiparametric Estimation of a Two‐component Mixture Model where One Component is known
Authors: BORDES LAURENT , DELMAS CÉLINE , VANDEKERKHOVE PIERRE
Published: May 2006

Abstract. We consider a two‐component mixture model where one component distribution is known while the mixing proportion and the other component distribution are unknown. These kinds of models were first introduced in biology to study the differences in expression between genes. The various estimation methods proposed till now have all assumed that the unknown distribution belongs to a parametric family. In this paper, we show how this assumption can be relaxed. First, we note that generally the above model is not identifiable, but we show that under moment and symmetry conditions some ‘almost everywhere’ identifiability results can be obtained. Where such identifiability conditions are fulfilled we propose an estimation method for the unknown parameters which is shown to be strongly consistent under mild conditions. We discuss applications of our method to microarray data analysis and to the training data problem. We compare our method to the parametric approach using simulated data and, finally, we apply our method to real data from microarray experiments.
A FLAVOPROTEIN FROM ARUM SPADIX
Authors: JAMES W. O. , ELLIOTT DAPHNE C.
Published: May 2006

summary

A flavoprotein has been extracted from the mitochondria ofArum spadix. The prosthetic group is flavine‐adenine‐dinucleotide and the enzyme behaves as a DPN‐specific cytochrome c reductase. It is also autoxidizable. Its respiratory function is discussed.

The existence of an autoxidizable flavoprotein in extracts from Arum spadices was observed by James and Beevers (1950) and its possible respiratory significance recognized. Extraction from the tissue in a form suitable for further investigation was not found possible; but its extraction and partial purification from separated mitochondria has now been achieved. In the following paper the method of extraction and the examination of the product are described. The enzyme proves to be a fairly stable flavoprotein with a flavine‐adenine‐dinucleotide (FAD) prosthetic group, a high degree of specificity for DPN (coenzyme I) and the ability to reduce cytochrome c rapidly. It is also autoxidizable and the reductase and terminal oxidase functions have not yet been separated.
THE EFFECT OF GIBBERELLIG ACID ON A GENETIC DWARF IN LOLIUM PERENNE
Authors: COOPER J. P.
Published: May 2006

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).
A NOTE ON TWO FRESHWATER DINOFLAGELLATES
Authors: CRIDLAND ARTHUR A.
Published: May 2006

Summary

A new species of Dinoilagellate, Gymnodinium hippocastamm, is described. Its resting spore is compared with Dinastridium sexangulare Pascher. Tetradinium chiastospomm Harris is recombined as Gymnodinium chiastospomm (Harris).
THE UPTAKE OF PHOSPHATE BY EXCISED MYCOR‐RHIZAL ROOTS OF THE BEECH
Authors: HARLEY J. L. , McCREADY C. C. , BRIERLEY J. K.
Published: May 2006

Summary

The temperature coefficients of phosphate absorption by beech mycorrhizas for temperature intervals below 20°C. were found to be above 2 regardless of the external concentration applied. Similar Q1o values were obtained for their constituent fungal and host tissues when exposed separately to phosphate solutions. The proportion of absorbed phosphate passing to the host through the fungal sheath was unaffected by temperature in very high or very low phosphate concentrations and the Q1o values for absorption by both tissues were of the expected magnitude. By contrast the proportion of phosphate passing to the host from intermediate concentrations (3.2 mM) was increased by low temperatures so that the estimates of Q1o for the host were lower than expected.

Similarly, the inhibitors sodium azide and iodoacetic acid diminished uptake by both fungus and host in high and low concentrations of phosphate but did not affect the amount absorbed into the host from 3.2 mM phosphate.

In concentrations of 3.2 mM phosphate also, separation of the fungal and host tissue increased their absorption rates over short periods but not over long periods of time.

In the discussion, these results are considered together with previous experiments and it is concluded that in ecologically probable conditions phosphate passes to the host through the living hyphae of the sheath.
STUDIES IN BRITISH PRIMULAS
Authors: CLIFFORD H. T.
Published: May 2006

Summary

In Britain the cowslip and primrose are widely distributed and often grow intermixed or in adjacent habitats. Their flowering times overlap and apparent F1 hybrids between them are well known in the field but are numerically rare; apparent backcross plants have also been reported but are extremely rare. Experimental studies have shown that the artificial F1 hybrid is difficult to obtain and is only partially fertile, but that both the back‐cross and the F2 generations are quite vigorous under garden conditions. This being so gene flow between the species is possible and data were collected to determine if it had occurred.

As no obvious hybrid swarms were encountered, some method of classifying populations had to be devised so that those likely to contain unrecognized introgressed individuals were grouped together. To bring this about populations of either species growing in the absence of the other were regarded as pure populations, and those in which the species grew together or in the company of apparent F1 hybrids were regarded as mixed populations. It was assumed that the mixed populations would contain more introgressed plants than the pure populations.

Since the species showed no sign of discordant variation in the mixed populations the usual method of comparing populations diagrammatically by means of radiate indicators was not applicable. Instead, biometrical methods were employed. Three floral dimensions were selected for investigation. The inheritance of these in artifical crosses was also studied so that their behaviour was known. The plants from each population were classified into one of three groups, primroses, cowslips and apparent F1 hybrids. Pure populations and mixed populations were then compared in respect of the means and variances of the three dimensions.
POPULATION DIFFERENTIATION IN AGROSTIS TENUIS SIBTH.
Authors: BRADSHAW A. D.
Published: May 2006

Summary

In some of thirty‐seven populations of Agrostis tennis and A. stolonifera sampled by tillers and grown as spaced plants, the incidence of infection by the fungal parasite ‘Choke’, Epichloe typhina, has been found to be remarkably high. These populations are from environments in which vegetative growth is important owing to the incidence of heavy grazing, exposure, etc.

A comparison of the growth of infected and non‐infected plants shows that infection, in preventing inflorescence production, causes a considerable increase in tiller density, without any other deleterious effects. These effects are of advantage to plants growing under conditions where vegetative growth is important.

It is therefore concluded that infection of Agrostis sp. by Epichloe must be considered to be not an example of parasitism but of a curious form of symbiosis.
INCLINED POINT QUADRATS
Authors: WILSON J. WARREN
Published: May 2006

Summary

‘Relative frequency’ recorded by point quadrats measures not the actual area of foliage but the area projected in the direction in which the quadrat lies. Accordingly the relative frequency varies both with the slope of the foliage and also—when inclined quadrats are used—with the inclination of the quadrat. A theoretical study reveals that variation in relative frequency resulting from differences in foliage angle is greatest for vertical quadrats, is considerably reduced when (as suggested by Tinney, Aamodt and Ahlgren) quadrats are inclined at 45°, and is least when quadrat inclination is 32.5°. Accordingly the usual, vertical position for point quadrats is the worst possible one, since it results in the most erroneous estimates of percentage contribution (area basis); while with quadrats inclined at 32.5° errors are greatly reduced and are of an order acceptable in general survey work.
THE NATURE OF THE VARIATION IN FLOWER COLOUR IN THE GENUS LATHYRUS
Authors: PECKET R. C.
Published: May 2006

Summary

An examination of the flowers of nineteen species of the genus Lathyrus, which presented a considerable range in colour from red to blue, has revealed a marked uniformity in the anthocyanin pigments. Up to three closely related anthocyanidins were found in each species, namely, delphinidin, petunidin and malvidin. No other anthocyanidin was detected in any species. The pigments occurred as monoglycosides, not as diglycosides as reported by earlier workers, and behaved chromatographically as 3‐monoglucosides. L. sativus L. was exceptional, however, in that all the pigment was apparently present as free aglycone.

Blueness of whole flowers or of wing petals was frequently correlated with, and is believed to be due to, the presence of the flavonols quercetin and kaempferol.
INTERGLACIAL DEPOSITS AT TRAFALGAR SQUARE, LONDON
Authors: FRANKS J. W.
Published: May 2006

Summary

Fossiliferous gravels were discovered during recent building operations on the south side of Trafalgar Square. At a later date organic deposits were exposed and an investigation of their plant remains was undertaken by the writer.

A similar organic deposit had previously been described from the site of the Admiralty Offices (Abbott, 1892). In that work the following plants were recorded: Amblystegium ripanum Schimp., Hypninn stramineum Dicks., H. fluitans Hedw., Potamogeton sp., Lemna cf. polyrhiza, Ceratophyllum demersnm L., Polygonum sp., Rumex sp., Carex sp., Scirpus sp., and Betula nana L. With the exception of B. nana all the vascular plants recorded above have been also recognized in the present study. It seems probable that the record of B. nana was due to mis‐identification, since the general aspect of the flora is not one of cold or open conditions.

The mammalian and molluscan remains from the present site have been studied by Dr. A. J. Sutcliffe and Mr. M. P. Kerney and will be published in detail later. The list of mammals forms an interesting counterpart to the plant determinations and is as follows: Panthera spelaea (Goldfuss), cave lion; Rhinoceros sp. indet., rhinoceros; Palaeoloxodon antiquas (Falconer), straight‐tusked elephant; Bos primigenius Bojanus, wild ox; Hippopotamus amphibius Linn., hippopotamus; Cervus elephas Linn., red deer; Dama cf. dama (Linn.), fallow deer. In addition a coprolite suggests that hyaenas may have been present and remains of bears not represented at this site have been found on two previous occasions during nearby excavations in other parts of the same terrace.
GARBOXYLASE IN CARROTS AND POTATOES
Authors: JAMES W. O. , RICHENS ANNE M.
Published: May 2006

Summary

The carboxylase of carrots is extracted almost wholly in the clear supernatant solution after all particles have been centrifuged down at forces up to 100,000 × g. There is very little carboxylase in fresh potatoes kept in air; but their ability to decarboxylate pyruvic acid increases steadily with storage under nitrogen. The activity is again found in the soluble fraction; but is not certainly enzymatic. These results are discussed in relation to the known differences between the anaerobic respirations of carrots and potatoes.
AN AGEING PROCESS IN EXCISED ROOTS OF GROUNDSEL (SENECIO VULGARIS L.)
Authors: HANNAY J. W. , BUTCHER D. N.
Published: May 2006

Summary

The growth and ageing of individual meristems of excised groundsel roots is described. Their behaviour upon repeated subculture is basically similar to that described by other workers for excised tomato roots, although excised groundsel roots require a greater concentration of sucrose for optimal growth than do excised tomato roots. However, growth in low‐sugar media can be considerably improved by adding small amounts of 2‐naphthoxyacetic acid.

When roots grow vigorously in media containing the optimal sucrose concentration, or in low‐sugar media supplemented with 2‐naphthoxyacetic acid, they show signs of ageing after a few passages and usually stop growing after about 10 weeks. Roots in low‐sugar media grow less vigorously but survive longer, 1‐naphthoxyacetic acid is a very effective ‘anti‐ageing’ substance in that it enhances survival of roots in high‐sugar media, or in media supplemented with 2‐naphthoxyacetic acid.

The ageing process appears to be under the control of a hormonal factor which is not β‐indolylacetic acid.
THE DIATOMS OF A CORE FROM ESTHWAITE WATER
Authors: ROUND F. E.
Published: May 2006

Summary

The diatom flora of a core taken from the region of the central buoy in Esthwaite has been analysed quantitatively and qualitatively. The diatom flora of the sediments laid down from the early zones of the Late‐glacial to the present day can be subdivided into five periods characterized by indicator species and variations in diatom productivity. The zones in Esthwaite have been compared with those from Windermere and Kentmere and shown to agree in general features, indicating a similar historical development for all three lake basins. The diatom periods show good correlation with the zoning derived from pollen analysis; and the change at the Boreal‐Atlantic Transition from base‐rich to base‐poor status, which was first detected in Kentmere, has been substantiated in Esthwaite. Comparison with the present‐day diatom flora suggests that a transition to eutrophic conditions, detected in late Post‐glacial time, is still occurring.
PATTERN OF DISTRIBUTION OF CHEMICAL CONSTITUENTS IN FLUE‐CURED VIRGINIA TOBACCO LEAF
Authors: SASTRY A. S. , RAMAKRISHNAYYA B. V.
Published: May 2006

Summary

It has been observed that the yellowing in the flue‐cured tobacco leaf starts from tips and margins and progresses gradually towards the base and midrib. A study of the pattern of distribution of chemical constituents in the different regions of the leaf was undertaken to see how it tallied with the pattern of yellowing.

Twenty leaves were cut into two halves each by removing the midrib and each half was again cut into six portions such as base, middle, tip, lower margin, middle margin and upper margin. The segments from corresponding regions were mixed. The twelve composite samples thus obtained were analysed for moisture, total nitrogen, protein nitrogen, nicotine, total sugars and starch.

It was found that there was a gradient in these constituents and that the tips and margins which yellowed first contained more total nitrogen, protein nitrogen and nicotine and less moisture and starch than the areas near the base and midrib.
TYPES OF NECTAR IN ANGIOSPERMS
Authors: PERCIVAL MARY S.
Published: May 2006

Summary

The nectar of 889 species and some fifty varieties of Angiosperms has been analysed by paper partition chromatography.

Ten different types of nectar are distinguished (with two or three very uncommon types in addition) and are broadly classified into:

Nectars with dominant sucrose.

Balanced nectars with about equal amounts of sucrose, fructose and glucose.

Nectars with dominant fructose + glucose.

Three oligosaccharides occurring in nectar are identified and a fourth is named tentatively.

Eight hundred and twenty‐eight species appear to have nectar of constant composition: sixty‐one species have nectar which varies distinctly. The variation does not appear to be linked with locality or date of sampling.

The distribution of nectar types is traced through the Herbaceae.

Sucrose‐dominated nectars appear to be associated with long‐tubed flowers having protected nectar, and fructose +glucose‐dominated nectars with ‘open’flowers having unprotected nectars.

Many humble‐ and honey‐bee, butterfly and moth flowers have nectars with sucrose more or less strongly predominating over fructose and glucose.

The climax groups of the Cruciferae, Umbelliferae, a section of the Compositae, the Euphorbiales and the herbaceous Rosaceae have a completely broken‐down nectar of equal parts of fructose and glucose which is technically honey.

The preference of Apis mellifera for certain sugar mixtures and the types of nectar in some honey‐bee flowers are explored.
PLANT GROWTH AND THE AERIAL ENVIRONMENT
Authors: HUGHES A. P. , EVANS G. C.
Published: May 2006

Summary

A detailed description is given of the growth of Impatiens parviflora DC in the laboratory at 15° C and saturation deficits of 1.5 or 2.0 mm Hg, illuminated for a 16‐hour day with light quantities of 11.2, 13.8, 20.6 and 26.2 cal./cm2/day. Growth under these conditions is compared with growth under artificial shades in the field, described in paper I of this series. The description and comparison cover growth in dry weight and leaf area, relative growth rate and relative leaf growth rate, unit leaf rate and leaf‐area ratio, specific leaf area, the distribution of dry matter between leaf, stem and root, and the dry weight/fresh weight ratios of leaf, stem and root. In all these account is taken of ontogenetic drifts up to dry weight of 500–600 mg (reached at an age of about 6 weeks) above which analysis is complicated by self‐shading.

Nearly all the comparisons reveal closely similar plants, passing through similar ontogenetic drifts, and make it possible to use the laboratory studies, which in general reveal relationship with greater detail and precision, to help to interpret growth in the field.

Observations are included on the effects of transferring plants from the lowest to the highest light and vice versa. The complications which this causes in the calculation of unit leaf rate are discussed. When they have been overcome it is shown that plants transferred to a given intensity have a unit leaf rate almost identical with that of plants grown in this intensity, differences in growth being due to differences in leaf‐area ratio (mainly reflecting differences in specific leaf area). In other respects adaption to a new light climate is largely complete within a week. The leaf growth of adapted and transferred plants is in harmony with the hypothesis that leaf expansion is controlled by a balance between extension due to water uptake by cells with high osmotic pressure and loss of cell wall plasticity by growth in wall thickness.

Both field and cabinet observations yield a similar relationship between specific leaf area and unit leaf rate. It is shown that this relationship accounts for the relatively slight changes in relative growth rate with changing light at medium intensities. A comparison is also made of unit leaf rates in the field and in the cabinets, for equal mean daily quantities of visible radiation expressed in absolute units, problems of such measurements having been discussed. While closely similar at very low intensities, the curves rapidly diverge at higher intensities, unit leaf rate around 3.3 mg/cm2/week being reached at 26 cal./cm2/day in the cabinets and 51 cal./cm2/day in the field. Finally, the efficiency of conversion of visible radiation is shown to be about 15% for the lowest intensity in the cabinets, falling to 12.5% at the highest, and 3% in full daylight.
THE COMPARATIVE BIOLOGY OF CLOSELY RELATED SPECIES LIVING IN THE SAME AREA
Authors: HARPER JOHN L. , McNAUGHTON I. H.
Published: May 2006

Summary

Seeds of Papaver rhoeas, P. dubium, P. lecoqii, P. argemone and P. apulum were sown in garden plots at a range of densities in pure stands and mixtures of two species. The plants reacted to density by a reduced chance of establishment and a plastic reduction of plant weight and capsule numbers—the species did not differ in their reactions to density in pure stands.

In mixed populations the chance of establishment of a species was reduced when its own density in the mixture was increased—the density of the associated species exerted a less significant influence.

The species in lower proportion in a mixture gave the more successful establishment from seed—and it is argued that the persistence of mixed populations is therefore favoured in comparison with pure stands.
STUDIES ON CYSTOPHYLLUM MURICATUM (TURNER) J. AGARDH, 1848
Authors: NIZAMUDDIN MOHAMMED
Published: May 2006

Summary

The structure, growth and life history of Cystophyllum muricatum has been studied. Growth is initiated by a single 3‐sided apical cell in the axis and in the receptacle. Three tissues— the meristoderm, the cortex and the medulla—are formed. The surface growth is initiated by the meristematic activity of the meristoderm cells. Cortical cells in the basal parts of the axis function as storage cells for they contain dense chromatophores. Hyphae function as mechanical as well as storage tissues. The initial cell of a conceptacle develops a tongue filament of three cells. Oogonia are embedded on the wall of the conceptacle and simultaneous oogonial discharge occurs. Four primary rhizoids are produced on the embryo. Paraphyses appear to be haploid and the apical cell diploid. Vesicle character is suggested as diagnostic character on the generic level.
THE STRATIGRAPHY AND POLLEN ANALYSIS OF LAKE DEPOSITS NEAR TADGASTER, YORKSHIRE
Authors: BARTLEY DAVID D.
Published: May 2006

Summary

The stratigraphy and pollen analysis of the deposits show that this is a lake basin which during the Late‐glacial period was partially filled by lake clays and muds. One of the main interests of the pollen diagrams lies in the division of zone I into three sub‐zones showing a minor climatic oscillation which seems to be comparable with the Bölling oscillation of northern Europe. During Post‐glacial time the greater part of the deposits has been muds but on one side a fen developed which in early zone VI was sufficiently dry to support birch and pine wood. Later in zone VI the water table must have risen slightly because the fen peats were gradually covered by a rather oxidized mud suggesting that the fen became replaced by a shallow swamp with a widely fluctuating water table. In the Atlantic period the basin was reflooded and the more central deposits were covered by a layer of mud. Later in the central region, swamp and eventually Sphagnum bog communities developed. The whole area is now covered by a silty soil and forms a flat meadowland.
POLLEN‐ANALYTICAL DATA FROM URSWICKTARN AND ELLERSIDE MOSS, NORTH LANCASHIRE
Authors: OLDFIELD FRANK , STATHAM D. C.
Published: May 2006

Summary

Stratigraphic and pollen‐analytical data from the margin of Urswick Tarn and from the centre of Ellerside Moss are presented and discussed. The diagrams record episodes in the local ecological history from the early part of Post‐glacial pollen zone VI almost up to the present day. It is suggested that at Urswick Tarn there was a phase of lowered lake level during zone VI contemporary with that recorded at Hawes Water in Lonsdale (Oldfield, 1960a). The Ellerside Moss record begins early in pollen zone Vila and at the end of this zone, both diagrams show a clearly marked ‘Elm Decline’separated from a subsequent ‘Landnam’phase (cf. Iversen, 1941; Morrison, 1959; etc.). Above this horizon, most of the pollen‐analytical changes in the diagrams seem to be mainly the result of successive periods of human interference with the local vegetation; the final episode at Urswick Tarn records nineteenth‐century land‐use in the area.
STUDIES IN THE PHYSIOLOGY OF LICHENS
Authors: SMITH D. C.
Published: May 2006

Summary

The main carbohydrates soluble in 80% alcohol in Peltigera polydactyla are mannitol and a galactose‐mannitol glycoside. The main carbohydrates obtained by mild acid hydrolysis of the insoluble residue are galactose and mannose, together with smaller amounts of glucose and a pentose provisionally identified as xylose. The utilization of the glucose absorbed by Peltigera discs in 24 hours is of the following approximate pattern: 20% is released as carbon dioxide, 20% is converted to an ‘insoluble’ glucose polysaccharide, and the remaining 60% is retained in the ‘soluble’extract—about 45% to 50% as mannitol, about 5% as the glycoside, and the remainder as unidentified substances. No free glucose could be detected in extracts of discs fed with labelled glucose. Dissection experiments did not reveal any qualitative differences between the carbohydrates of the ‘algal zone’ and medulla. The medulla contained more insoluble carbohydrate than the‘algal zone’. The ‘algal zone’ was the only region in which synthesis of the glucose polysaccharide and the galactose‐mannitol glycoside from absorbed glucose could be detected. There is as yet insufficient evidence to indicate the role of mannitol in the metabolism of P. polydactyla, but it is possible that it is a storage carbohydrate.
THE MATING SYSTEMS OF FUNGI
Authors: BURNETT J. H. , BOULTER M. EILEEN
Published: May 2006

Summary

Isolations of Mycocaha denudata and M. duriaeana were grown in plate culture and their mating systems studied. The former species is heteromictic and shows both bipolar diaphoromixis and facultative homo‐heteromixis, the latter species is almost certainly homomictic. None of these mating systems have been found before in Nidulariales. It is suggested that the abundance, morphological variation and ecological tolerance of these species may be related to their kinds of mating system. Facultative homo‐heteromixis in M. denudata results in spores being produced in a single peridiolum which are either homocaryotic or heterocaryotic in respect of mating‐type factors. The condition is due to a dominant gene Pd which determines a precocious division of the four nuclei, formed by a normal meiosis, in each basidium. The eight nuclei so formed appear to migrate at random, in respect of the mating‐type factors they carry, into the basidiospores which are each ultimately binucleate. This mechanism is not yet known in other Basidiomycetes.

Isolations of M. denudata fell into two groups (I and II) between which there was complete sterility but no other constant distinguishing features could be observed between them. The occurrence of such groups is thought to be of significance in fungi and at present it seems best to regard them as comparable to sibling species. Four mating‐type factors were identified amongst the six isolations of group I, seven amongst the sixteen isolations of group II. Estimates of the total numbers of mating‐type factors in group I and group II are seven to eight and twelve to thirteen respectively. Thus, like other Nidulariales, M. denudata appears to have only a relatively small number of mating‐type factors and the relation of this to inbreeding and dispersal mechanisms is discussed.
MOVEMENT OF GROWTH REGULATORS IN PLANTS
Authors: McCREADY C. C. , JACOBS W. P.
Published: May 2006

Summary

Indoleacetic acid and 2,4‐dichlorophenoxyacetic acid, labelled with carbon‐14, were applied in agar blocks to one end of sections cut from the petioles of primary leaves of Phaseolus vulgaris at various stages in their development. The movement of 14C by polar transport into agar blocks at the other end of the sections was measured and compared with the elongation of the sections. With both auxins there was a steady decline in the polarity of movement of 14C—due mainly to a steady increase of movement in the acropetal direction—in petioles from successively older plants. This decreasing polarity was closely associated with a progressive decrease in the ability of the sections to grow in length.
EPIDERMAL STRUCTURE AND DEVELOPMENT OF STOMATA IN EPHEDRA FOLIATA BOISS.
Authors: PANT D. D. , MEHRA BHARATI
Published: May 2006

Summary

The epidermal structure of the leaf and stem of Ephedra foliata Boiss. is described. The epidermis of internodes and leaves shows longitudinal rows of cells and stomata. In the nodes and the leaf bases the stomata are irregularly orientated. The subsidiary cells are perigene and the development of stomata is typically haplocheilic.
AN ADDITION TO THE BISPORIC EMBRYO SACS—THE DICRAEA TYPE
Authors: MUKKADA A. J.
Published: May 2006

Summary

The embryo sac in Dicraea is tetra‐nucleate and follows a bisporic development. It comprises a single synergid, an egg cell and two juxtaposed antipodal cells. This justifies the establishment of a new type under the bisporic embryo sacs which may be designated as the Dicraea type.
ORGANELLE DISTRIBUTION IN THE STATOCYTE CELLS OF THE ROOT‐TIP OF VICIA FABA IN RELATION TO GEOTROPIC STIMULATION
Authors: GRIFFITHS HILARY J. , AUDUS L. J.
Published: May 2006

Summary

By means of the electron microscope a study has been made of the changes in organelle distribution in the cells of the root cap of Vicia faba seedlings resulting from a 20 minute geotropic stimulation in the horizontal position. From photographs of whole cells at constant magnification, counts were made of the numbers of amyloplasts, mitochondria and dictyosomes in each of four equal quarters of the cell divided along, and transverse to, the main root axis. The volumes of the characteristic endoplasmic reticulum masses per cell quarter were also measured.

The only bodies showing marked sedimentation to the lower side of the cell were the amyloplasts. The dictyosomes showed a small but statistically significant displacement into the quarter not occupied by the amyloplasts but since their concentration per unit of cytoplasm did not change, it was inferred that they moved passively in the cytoplasm displaced by the sedi‐menting amyloplasts. Similar trends were shown by the mitochondria but these did not reach 5% significance levels. There also appeared to be significant displacement of the endoplasmic reticulum masses into the upper halves of the cells.

The implications of these findings are discussed in the context of current theories of gravi‐perception in plants.
PRODUCTION OF PECTIC ENZYMES BY PATHOGENIC AND SYMBIOTIC RHIZOCTONIA STRAINS
Authors: PÉROMBELON M. , HADLEY G.
Published: May 2006

Summary

Five strains of Rhizoctonia, selected for their symbiotic and/or pathogenic characteristics, were investigated with regard to growth and pectic enzyme production in culture. Growth patterns of the strains were similar on glucose and pectin carbon sources, pectin being less efficient than glucose in terms of mycelial dry weight produced. Assays of endopolymethylgalacturonase, endopolygalacturonase and protopectinase in culture filtrates showed that on pectin media all of these enzymes were produced by each of the strains although the relative degree of activity varied. Enzyme production by the orchid endophyte strains used was no less than, and in one case was far greater than, that by the pathogenic strains. The significance of these results is discussed with regard to host/endophyte relationships.
THE RESPIRATION CLIMACTERIC IN APPLE FRUITS
Authors: HULME A. C. , JONES J. D. , WOOLTORTON L. S. C.
Published: May 2006

Summary

Changes in the activity, in terms of O2 uptake and CO2 output in presence of malate and succinate substrates and of succinic and malic dehydrogenases, diaphorase and cytoehrome‐c reductase, of mitochondrial preparations from the peel and pulp of apple tissue, were followed during the development of the respiration climacteric in fruit on the tree. There was a general increase in activity beginning in peel tissue. Oxidative phosphorylation by the mitochondrial preparations was maintained at a high level throughout the period. At the same time a threefold increase in malic enzyme (M.E.) and carboxylase activity was observed. It is suggested that these observations show that the climacteric rise in apple fruits attached to the tree is initiated by an increase in mitochondrial activity and develops through the joint action of increased activity of M.E. and carboxylase.
GERMINATION IN POLYGONUM
Authors: TIMSON J.
Published: May 2006

Summary

The results of a study of germination and seed dormancy in Polvgonum lapathifolium L., P. persicaria L., P. hydropiper L., P. mite Schrank and P. minus Huds. are presented. Method's of breaking this dormancy are reported and its causes investigated.
CARBOHYDRATE PHYSIOLOGY OF MYCORRHIZAL ROOTS OF BEECH
Authors: LEWIS D. H. , HARLEY J. L.
Published: May 2006

Summary

In order to test the relevance of previous results of this series to conditions operative in the intact plant, a technique was devised to simulate translocation of sucrose to mycorrhizal roots and to determine its morphological and biochemical destinations by the use of [14C]sugar. It was shown that the fungus can absorb sugar from the host and that its chemical destination is essentially similar to that of exogenous sucrose, namely a synthesis of mannitol, trehalose and glycogen.

In connection with the possibility of reciprocal flow from fungus to host, the ability of uninfected roots to utilize the soluble sugars of the fungus was tested. Whereas mycorrhizas readily absorb and metabolize mannitol and trehalose, uninfected roots have almost no ability to utilize mannitol and are restricted in their utilization of trehalose, throwing considerable doubt on the possibility of sugar absorption by host from fungus.

The hypothesis is developed that the fungus absorbs carbohydrates from the host and transforms them into reserve substances peculiar to itself, so maintaining a concentration gradient with respect to the host carbohydrate. The mycorrhizal system has the added advantage to the fungus that its reserve sugars are not readily re‐available to the host. As polyols are abundant in many angiosperm parasites, the Physiology of polyols in general is reviewed with the conclusion that the role postulated for this class of compound in mycorrhizas may be applicable to host‐parasite relations in general.
ON THE FLORAL ELEMENTS OF THE SEMI‐ARID ZONES OF INDIA AND THEIR ECOLOGICAL SIGNIFICANCE
Authors: BHARUCHA F. R. , MEHER‐HOMJI V. M.
Published: May 2006

Summary

Two zones of semi‐arid climate are recognized in India, one in the north contiguous with the desert of Thar, extending into Rajasthan, the Punjab and North Gujarat and the other in parts of the Deccan and Madras State in the south.

Analysis of the flora of these regions reveals that seventeen types of floral elements are represented in these semi‐arid zones. The Southern zone has higher percentages of the Indian element and, to some extent, of the Indo‐Malayan. On the other hand, the northern zone is richer in the North African‐Indian Desert (Saharo‐Sindian) element. North African Steppe element and in the Mediterranean‐Oriental element. The elements of tropical and warm countries as well as the cosmopolitan element are equally frequent in both the zones. The percentage of the endemic element is very low in these regions, not exceeding 2.5%.

The pattern of distribution of these floral elements is explained on the basis of the bioclimatic conditions prevailing in the Afro‐Asian continents.

Finally, it is shown that contrasting seasonal aspects in the annual cycle of the climate—the alternation of a very long dry period with a short rainy season and of a cool and short‐day winter with a hot long‐day summer—permit the development of several floral elements.