Influence of agricultural management, sward structure and food resources on grassland field use by birds in lowland England.

Agricultural management of grassland in lowland Britain has changed fundamentally in the last 50 years, resulting in spatial and structural uniformity within the pastoral landscape. The full extent to which these changes may have reduced the suitability of grassland as foraging habitat for birds is unknown. This study investigated the mechanisms by which these changes have impacted on birds and their food supplies. We quantified field use by birds in summer and winter in two grassland areas of lowland England (Devon and Buckinghamshire) over 3 years, relating bird occurrence to the management, sward structure and seed and invertebrate food resources of individual fields. Management intensity was defined in terms of annual nitrogen input. There was no consistent effect of management intensity on total seed head production, although those of grasses generally increased with inputs while forbs were rare throughout. Relationships between management intensity and abundance of soil and epigeal invertebrates were complex. Soil beetle larvae were consistently lower in abundance, and surface-active beetle larvae counts consistently higher, in intensively managed fields. Foliar invertebrates showed more consistent negatively relationships with management intensity. Most bird species occurred at low densities. There were consistent relationships across regions and years between the occurrence of birds and measures of field management. In winter, there was a tendency towards higher occupancy of intensively managed fields by species feeding on soil invertebrates. In summer, there were few such relationships, although many species avoided fields with tall swards. Use of fields by birds was generally not related to measures of seed or invertebrate food abundance. While granivorous species were perhaps too rare to detect a relationship, in insectivores the strong negative relationships (in summer) with sward height suggested that access to food may be the critical factor. While it appears that intensification of grassland management has been deleterious to the summer food resources of insectivorous birds that use insects living within the grass sward, intensification may have been beneficial to several species in winter through the enhancement of soil invertebrates. Synthesis and applications. We suggest that attempts to restore habitat quality for birds in grassland landscapes need to create a range of management intensities and sward structures at the field and farm scales. A greater understanding of methods to enhance prey accessibility, as well as abundance, for insectivorous birds is required.

Leaving final-cut grass silage in situ overwinter as a seed resource for declining farmland birds

The loss of seed-rich wintering habitats has been a major contributory cause of farmland bird population declines in western Europe. Agricultural grasslands are particularly poor winter foraging habitats for granivorous birds, which have declined most in the pastoral farming regions of western Britain. We describe an experiment to test the utility of fertile ryegrass (Lolium) swards as a potentially rich source of winter seed for declining farmland birds. Four patches of final-cut grass silage were allowed to set seed and were left in situ overwinter. Half of each patch was lightly aftermath grazed in an attempt to increase the accessibility of the seed to foraging birds and reduce the perceived predation risk. Large numbers of yellowhammers (Emberiza citrinella) and reed buntings (E. schoeniclus) foraged on the seeded plots throughout the winter. They preferred to forage on ungrazed seeded plots, where the accumulation of senescent foliage resulted in a 14% average loss in silage yield in the following season. However, seed produced on the plots also led to sward regeneration, increasing subsequent yields on some plots. The technique offers clear benefits as a potential future agri-environment measure for declining granivorous birds, with wide applicability, but requires further development to minimise sward damage and costs to the farmer. Autumn grazing should reduce sward damage, but at the cost of reduced usage by buntings. Using the technique just prior to reseeding would be one way of avoiding any costs of sward damage.

Effects of host plant drought stress on the performance of the bird cherry-oat aphid, Rhopalosiphum padi (L.): a mechanistic analysis

1. The growth (increase in height and leaf number) of four grass species was reduced by a -0.5 MPa drought stress, but the performance of an associated herbivore, Rhopalosiphum padi (L.), was not affected consistently. The intrinsic rate of increase of R. padi was reduced by drought stress on three grass species, including Dactylis glomerata (L.), but was unaffected on Arrhenatherum elatius (L.). Therefore, there is no general relationship in the effect of plant drought on an insect herbivore, even among closely related host plant species. 2. Drought stress increased the quality of plant phloem sap, as indicated by increased sieve element osmotic pressure and essential amino acid concentrations. Thus, diet quality could not account for the reduced performance of R. padi under drought stress. The concentration of essential amino acids in the phloem of well-watered A. elatius was, however, lower than that of well-watered D. glomerata, correlating with the decreased performance of aphids on well-watered A. elatius. 3. There were no differences in aphid feeding duration between watering treatments or plant species but sap ingestion rates were reduced significantly under drought stress. 4. Using the measure of dietary amino acid concentrations and the estimate of sap ingestion, the essential amino acid flux through aphids was calculated. Compared with the flux through aphids feeding on well-watered D. glomerata, there was a reduction in aphids feeding on drought-stressed D. glomerata and drought-stressed A. elatius due to lower sap ingestion rates. The flux through aphids on well-watered A. elatius was also reduced due to low phloem essential amino acid concentrations. Thus, the performance of an aphid is correlated with the availability and accessibility of essential amino acids.

Type specimens of G.E. Post in Beirut and The Natural History Museum, London

The Flora of Syria, Palestine and Sinai, a pioneer Flora of the region, was published in 1896 by George Edward Post (1838–1909). Lesser known are his series of Diagnoses plantarum novarum orientalium, published in the Journal of the Linnean Society Botany, and 10 papers, Plantae Postianae, which appeared in Swiss journals from 1890 to 1900. A greatly expanded second edition of the Flora was prepared by John Edward Dinsmore and published in Beirut in 1932 and 1933. Post's plant collection is part of the Post Herbarium (BEI), with about 63 000 specimens, that has been well maintained, despite civil war and inadequate staffing. This work involves the identification of around 150 types in BEI and BM, and improvement of the accessibility of the specimens. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159, 315–321.

Enhanced phosphopeptide isolation by Fe(III)-IMAC using 1,1,1,3,3,3-hexafluoroisopropanol

IMAC can be used to selectively enrich phosphopeptides from complex peptide mixtures, but co-retention of acidic peptides together with the failure to retain some phosphopeptides restricts the general utility of the method. In this study Fe(III)-IMAC was qualitatively and quantitatively assessed using a panel of phosphopeptides, both synthetic and derived from proteolysis of known phosphoproteins, to identify the causes of success and failure in the application of this technique. Here we demonstrate that, as expected, peptides with a more acidic amino acid content are generally more efficiently purified and detected by MALDI-MS after Fe(III)-IMAC than those with a more basic content. Modulating the loading buffer used for Fe(III)-IMAC significantly affects phosphopeptide binding and suggests that conformational factors that lead to steric hindrance and reduced accessibility to the phosphate are important. The use of 1,1,1,3,3,3-hexafluoroisopropanol is shown here to significantly improve Fe(III)-IMAC enrichment and subsequent detection of phosphopeptides by MALDI-MS.

Enhanced phosphopeptide isolation by Fe(III)-IMAC using 1,1,1,3,3,3-hexafluoroisopropanol

IMAC can be used to selectively enrich phosphopeptides from complex peptide mixtures, but co-retention of acidic peptides together with the failure to retain some phosphopeptides restricts the general utility of the method. In this study Fe(III)-IMAC was qualitatively and quantitatively assessed using a panel of phosphopeptides, both synthetic and derived from proteolysis of known phosphoproteins, to identify the causes of success and failure in the application of this technique. Here we demonstrate that, as expected, peptides with a more acidic amino acid content are generally more efficiently purified and detected by MALDI-MS after Fe(III)-IMAC than those with a more basic content. Modulating the loading buffer used for Fe(III)-IMAC significantly affects phosphopeptide binding and suggests that conformational factors that lead to steric hindrance and reduced accessibility to the phosphate are important. The use of 1,1,1,3,3,3-hexa-fluoroisopropanol is shown here to significantly improve Fe(III)-IMAC enrichment and subsequent detection of phosphopeptides by MALDI-MS.

Colloidal stable silica encapsulated nano-magnetic composite as a novel bio-catalyst carrier

A colloidal stable silica-encapsulated magnetic nano-composite of a controlled dimension is, for the first time, employed to carry beta-lactamase via chemical linkage on the silica overlayer: activity study reflects that this new type of immobilisation allows site (enzyme) isolation, accessibility as good as free enzyme and recovery & reusability upon application of magnetic separation.

The trapping and decomposition of toxic gases such as hydrogen cyanide using modified mesoporous silicates

Selected silicas were modified with the covalently bound ligand 2,6-bis(benzoxazoyl)pyridine (BBOP), equilibrated with copper(II) nitrate, then challenged with toxic vapour containing HCN (8000 mg m(-3) at 80% relative humidity). The modified SBA-15 material (Cu-BBOP-SBA-15) had an improved breakthrough time for HCN (36 min at a flow rate of 30 cm(3) min(-1)) when compared to the other siliceous materials prepared in this study, equating to a hydrogen cyanide capacity of 58 mg g(-1), which is close to a reference activated carbon adsorbent (24 min at 50 cm(3) min(-1)) that can trap 64 mg g(-1). The enhanced performance observed with Cu-BBOP-SBA-15 has been related to the greater accessibility of the functional groups, arising from the ordered nature of the interconnected porous network and large mesopores of 5.5 nm within the material modified with the Cu(II)-BBOP complex. Modified MCM-41 and MCM-48 materials (Cu-BBOP-MCM-41 and Cu-BBOP-MCM-48) were found to have lower hydrogen cyanide capacities (38 and 32 mg g(-1) respectively) than the Cu-BBOP-SBA-15 material owing to the restricted size of the pores (2.2 and <2 nm respectively). The materials with poor nano-structured ordering were found to have low hydrogen cyanide capacities, between 11 and 19 mg g(-1), most likely owing to limited accessibility of the functional groups. (C) 2004 Elsevier Inc. All rights reserved.

Novel solid networks containing Sn-H as a greener replacement for soluble alkyl Sn-H reagents in radical assisted organic synthesis

DiGrignard reagents of the form XMg(CH2)(n)MgX, where X = Br or I and n = 6, 8, 10 or 12, were allowed to react with PhSnCl3 to produce highly cross-linked Ph-Sn polymeric networks. The Sn-H moiety was incorporated into these insoluble network polymers by treatment with Br-2 and NaBH4. Excellent accessibility of the Sn-H was displayed by these solvent penetrable but insoluble networks, giving them higher Sn-H loadings than all previously reported supported reagents. These reagents were totally regenerable in NaBH4 for radical assisted organic synthesis and no detectable leaching of the Sn into solution was observed during these reactions.

Synthesis of fused cyclic systems containing medium-sized rings through tandem ROM-RCM of norbornene derivatives embedded in a carbohydrate template

A general approach for the synthesis of fused cyclic systems containing medium-sized rings (7-9) has been developed. The key steps involve a diastereoface-selective Diels-Alder reaction of the dienophiles 4a-d attached to a furanosugar with cyclopentadiene and ring opening (ROM)-ring closing metathesis (RCM) of the resulting norbornene derivatives 10a-d and 11a-d. Diels-Alder reaction of the dienophiles 4a-d with cyclopentadiene in the absence of a catalyst produced 10a-d as the major product arising through addition of the diene to the unhindered Si-face. The most interesting and new aspect of the Diels-Alder reaction of these dienophiles is the accessibility of the Re-face that was blocked by the alkenyl chains under Lewis acid catalysis producing the diastereoisomers 11a-d exclusively. The reversal of facial selectivity from an uncatalyzed reaction to a catalyzed one is unprecedented. The observed stereochemical dichotomy is attributed to rotation of the enone moiety along the or bond linking the sugar moiety during formation of the chelate 13. This makes the Re-face of the enone moiety in 4a-d unhindered. Diels-Alder reaction of the carbocyclic analogue 15 under Lewis acid catalysis produced a 1: 1 mixture of the adducts 16 and 17 confirming the participation of sugar ring oxygen in chelate formation. Finally ROM-RCM of 10a-d and 11a-d with Grubbs' catalyst afforded the cis-syn-cis and cis-anti-cis bicyclo-annulated sugars 21a-d and 23a-d, respectively, containing 7-9 membered rings.

Silica-encapsulated nanomagnetic particle as a new recoverable biocatalyst carrier

Enzymes are versatile biocatalysts with major advantages of ultrahigh reaction selectivity and specificity under mild conditions, which currently find increasing applications. However, their applications are often hampered by difficulties in recovery and recycling. As a result, we carried out detailed investigations on the synthesis and characterization of silica-encapsulated iron oxide magnetic nanoparticles of controlled dimension as an enzyme carrier. It is shown that the relatively smaller sized silica-coated magnetic nanoparticle prepared by the microemlusion technique can a carry bulky enzyme, beta-lactamase, via chemical linkages on the silica overlayer without severely blocking the enzymatic active center ( which is commonly encountered in conventional solid supports). An activity study by Michalis-Menten kinetics reflects that this new type of immobilization allows enzyme isolation with accessibility as good as free enzyme. The recovery and reusability of the nanoparticle-supported enzyme upon application of magnetic separation are also demonstrated.

Introducing assistive technologies (AT) into the existing homes of older people

The design of accessible environments, for use by all, is a legal requirement for all public buildings, under the Disability Discrimination Act 1995 (DDA, 1995) since October 1999 and the removal of all physical barriers becomes enforceable in 2004. Accessibility has transferred from being a social and moral issue to a legal requirement. The Research Group for Inclusive Environments at the University of Reading undertakes research to better understand methods to make the built environment more accessible. This paper presents the findings from the research project, Project Crystal, investigating the design of environments for better communication for deaf and hard of hearing people. At the last COBRA conference the preliminary findings from the pilot questionnaire were presented. During the year the questionnaire has been distributed more widely and a test environment has been used to investigate the effects the variables of lighting and colour have on people's ability to communicate. This paper will present some of the findings from the project, which is almost complete, and generalise on the effect wall surface design has on accessibility of an environment for people with a hearing impairment.

The children that time forgot: Reframing housing standards to incorporate children's needs

This paper presents the findings from a recent study funded by the Joseph Rowntree Foundation examining the housing and neighbourhood needs of 44 visually impaired children. Our research found that disabled people’s needs have been too narrowly based on ‘accessibility’ criteria, which do not take into account the health and safety issues so important for children. Indeed, the home environment is the main site of accidental death or injury for young children under 4 years, and children from low income families are particularly susceptible to burns, scalds, falls, swallowing foreign objects or poisonous substances within it (CRDU 1994). As disabled children are statistically more likely to be in low income families, this places them at high risk. If ‘accessibility’ is to be reconceived as design for usability throughout the lifecourse, this challenges us to move beyond the pragmatic but limited application of design prescriptions for disabled people as a separate and adult group, and to re-think all of the dimensions of the housing quality framework in the light of this expanded approach.

Effects of lactoperoxidase and hydrogen peroxide on rheological properties of yoghurt

The effects of activation of the lactoperoxidase (LPO) system by H2O2-NaSCN and hydrogen peroxide (H2O2) on the accessibility of sulphydryl groups (SH) in skimmed milk, and on the dynamic rheological properties of the resulting yoghurt were investigated. Four different concentrations of each reagent (20-80 mg H2O2-NaSCN/kg milk and 100-400 mg H2O2/kg milk) were compared. Clear negative correlations were noted between the accessibility of SH groups and both LPO activation rate and H2O2 concentration. Also the native PAGE pattern of the heat-treated samples showed that with increase in the H2O2-NaSCN and H2O2 concentrations, the level of interaction between beta-lactoglobulin (beta-Ig) and kappa-casein (K-CN) decreased. The complex modulus (G*) of skimmed milk yoghurts declined gradually with the decrease in the concentration of accessible SH groups accordingly. Tan delta values of yoghurt samples were found to be different from the control, but close to each other, indicating that protein interaction forces taking place in the formation of gel networks of treated yoghurts were different from the control.