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Mast cells have been linked to rheumatoid arthritis (RA) and are essential to the pathogenesis of RA-like disease in a mouse model. We describe a 34-year-old woman who developed Sjögren's syndrome concurrently with telangiectasia macularis eruptiva perstans (TMEP), a rare form of cutaneous mastocytosis. The patient had sicca symptoms with an abnormal minor salivary gland biopsy and decreased salivary flow, peripheral neuropathy, an 80 pound weight loss, and a macular erythematous rash that exhibited superficial perivascular mast cell infiltrates on biopsy of lesional skin. This case further underscores the link between mast cells and the development of autoimmunity.

Recent radio polarization observations have revealed a plethora of unexpected features in the polarized Galactic radio background that arise from propagation effects in the random (turbulent) interstellar medium. The canals are especially striking among them, a random network of very dark, narrow regions clearly visible in many directions against a bright polarized Galactic synchrotron background. There are no obvious physical structures in the ISM that may have caused the canals, and so they have been called Faraday ghosts. They evidently carry information about interstellar turbulence but only now is it becoming clear how this information can be extracted. Two theories for the origin of the canals have been proposed; both attribute the canals to Faraday rotation, but one invokes strong gradients in Faraday rotation in the sky plane (specifically, in a foreground Faraday screen) and the other only relies on line-of-sight effects (differential Faraday rotation). In this review we discuss the physical nature of the canals and how they can be used to explore statistical properties of interstellar turbulence. This opens studies of magnetized interstellar turbulence to new methods of analysis, such as contour statistics and related techniques of computational geometry and topology. In particular, we can hope to measure such elusive quantities as the Taylor microscale and the effective magnetic Reynolds number of interstellar MHD turbulence., 20 pages, 8 figures. Contribution to the proceedings of the conference 'Polarization 2005', September 12 to 15, Orsay, France. Replaced one figure, changed three figure captions

We have developed a technique of isolating elongated structures in galactic images, such as spiral arms, using anisotropic wavelets and apply this to maps of the CO, infrared and radio continuum emission of the grand-design spiral galaxy M51. Systematic shifts between the ridges of CO, infrared and radio continuum emission that are several $\kpc$ long are identified, as well as large variations in pitch angle along spiral arms, of a few tens of degrees. We find two types of arms of polarized radio emission: one has a ridge close to the ridge of CO, with similar pitch angles for the CO and polarization spirals and the regular magnetic field; the other does not always coincide with the CO arm and its pitch angle differs from the orientation of its regular magnetic field. The offsets between ridges of regular magnetic field, dense gas and warm dust are compatible with the sequence expected from spiral density wave triggered star formation, with a delay of a few tens of millions of years between gas entering the shock and the formation of giant molecular clouds and a similar interval between the formation of the clouds and the emergence of young star clusters. At the position of the CO arms the orientation of the regular magnetic field is the same as the pitch angle of the spiral arm, but away from the gaseous arms the orientation of the regular field varies significantly. Spiral shock compression can explain the generation of one type of arm of strong polarized radio emission but a different mechanism is probably responsible for a second type of polarization arm. (Shortened abstract.), Comment: 13 pages, 10 figures (2 in colour), accepted for publication in Astronomy and Astrophysics

We have mapped key molecular line probes (12CO, 13CO, C18O, HCN, HCO+) in two distinct regions in the spiral arms of the Whirlpool galaxy, M51. Line Velocity Gradient (LVG) analysis performed at a linear resolution of 135–210 pc (2.9–4.5 arcsec) suggests physical conditions in the Giant Molecular Cloud complexes (GMCs) of M51 very similar to those in the Milky Way: cold (T kin ∼ 15 K) clouds with moderate H2 density (n(H2) < 102.7 cm−3. We find indications for a galactocentric trend, with higher kinetic temperature for smaller radii. The data show little evidence for cloud heating by the massive star formation at our resolution of 135 pc. Our new deep ∼ 2 arcsec radio continuum images at 3.6 and 6 cm reveal the presence of some highly dust-obscured young star-forming regions within the molecular spiral arms.

Radio continuum emission is an excellent tracer of star formation in central regions of galaxies. We observed a sample of 20 galaxies with massive bars. The regular magnetic fields around the bar, as traced by the polarized emission, do not always follow the gas flow predicted from numerical simulations and show little compression by the shock. The galaxies with the longest bars show the strongest deviations of the magnetic field pattern from axial symmetry, and most of them host nuclear rings. The total magnetic fields in these nuclear rings of up to ≃ 100 μG are among the strongest fields known in spiral galaxies. The regular field in the nuclear ring of NGC 1097 is of spiral shape. Magnetic stress in the ring can drive mass inflow of about one solar mass per year which is sufficient to feed the active nucleus. This process may also work in non‐barred galaxies.

We present 3.5cm and 6.2cm radio continuum maps in total and polarized intensity of the barred galaxies NGC 1097 and NGC 1365. Both galaxies exhibit radio ridges roughly overlapping with the massive dust lanes in the bar region. The contrast in total intensity across the radio ridges is compatible with compression and shear of an isotropic random magnetic field. The contrast in polarized intensity is significantly smaller than that expected from compression and shearing of the regular magnetic field; this could be the result of decoupling of the regular field from the dense molecular clouds. The regular field in the ridge is probably strong enough to reduce significantly shear in the diffuse gas (to which it is coupled) and hence to reduce magnetic field amplification by shearing. This contributes to the misalignment of the observed field orientation with respect to the velocity vectors of the dense gas. Our observations, for the first time, indicate that magnetic forces can control the flow of the diffuse interstellar gas at kiloparsec scales. The total radio intensity reaches its maximum in the circumnuclear starburst regions, where the equipartition field strength is about 60\mu G, amongst the strongest fields detected in spiral galaxies so far. The regular field in the inner region has a spiral shape with large pitch angle, indicating the action of a dynamo. Magnetic stress leads to mass inflow towards the centre, sufficient to feed the active nucleus in NGC 1097. We detected diffuse X-ray emission, possibly forming a halo of hot gas around NGC 1097., Comment: 32 pages with 45 PostScript figures. Accepted for publication in A&A; Typos corrected 12/10/2005

The configuration of the regular magnetic field in M31 is deduced from radio polarization observations at the wavelengths 6, 11 and 20 cm. By fitting the observed azimuthal distribution of polarization angles, we find that the regular magnetic field, averaged over scales 1--3 kpc, is almost perfectly axisymmetric in the radial range 8 to 14 kpc, and follows a spiral pattern with pitch angles of $p\simeq -19\degr$ to $p\simeq -8\degr$. In the ring between 6 and 8 kpc a perturbation of the dominant axisymmetric mode may be present, having the azimuthal wave number m=2. A systematic analysis of the observed depolarization allows us to identify the main mechanism for wavelength dependent depolarization -- Faraday rotation measure gradients arising in a magneto-ionic screen above the synchrotron disk. Modelling of the depolarization leads to constraints on the relative scale heights of the thermal and synchrotron emitting layers in M31; the thermal layer is found to be up to three times thicker than the synchrotron disk. The regular magnetic field must be coherent over a vertical scale at least similar to the scale height of the thermal layer, estimated to be $h\therm\simeq 1$ kpc. Faraday effects offer a powerful method to detect thick magneto-ionic disks or halos around spiral galaxies., 17 pages, 16 figures, accepted for publication in A&A

Observations of the southern peculiar galaxy NGC 2442 with the Australia Telescope Compact Array in total and linearly polarized radio continuum at 6cm are presented and compared with previously obtained H$\alpha$ data. The distribution of polarized emission, a signature of regular magnetic fields, reveals some physical phenomena which are unusual among spiral galaxies. We find evidence for tidal interaction and/or ram pressure from the intergalactic medium compressing the magnetic field at the northern and western edges of the galaxy. The radial component of the regular magnetic field in the northern arm is directed away from the centre of the galaxy, a finding which is in contrast to the majority of galaxies studied to date. The oval distortion caused by the interaction generates a sudden jump of the magnetic field pattern upstream of the inner northern spiral arm, similar to galaxies with long bars. An unusual ``island'' of strong regular magnetic field east of the galaxy is probably the brightest part of a magnetic arm frequently seen in spiral galaxies, which appear to be phase-shifted images of the preceding optical arm. The strong magnetic field of the ``island'' indicates a past phase of active star formation when the preceding optical arm was exposed to ram pressure., Comment: 11 pages, 9 figures; revised version accepted by A&A, new sub-section added

The recent United Nations RIO+20 Conference on Sustainable Development highlighted the rapid increase in industrial mineral exploration and extraction over the past two decades ([ 1 ][1]). Endemic metallophyte plants, which have evolved where metal accumulations extend to the Earth's surface, have

We present a study of the magneto-ionic medium in the Whirlpool galaxy (M51) using new wide-band multi-configuration polarization data at L band (1-2 GHz) obtained at the Karl G. Jansky Very Large Array. By fitting the observed diffuse complex polarization $Q$+$iU$ as a function of wavelength directly to various depolarization models, we find that polarized emission from M51 at 1-2 GHz originates from the top of the synchrotron disk and then experiences Faraday rotation in the near-side thermal halo of the galaxy. Thus, the scale height of the thermal gas must exceed that of the synchrotron emitting gas at L band. The observed Faraday depth distribution at L band is consistent with a halo field that comprises of a plane-parallel bisymmetric component and a vertical component which produces a Faraday rotation of $\sim$ $-$9 rad m$^{-2}$. The derived rotation measure structure functions indicate a characteristic scale of rotation measure fluctuations of less than 560 pc in the disk and approximately 1 kpc in the halo. The outer scale of turbulence of 1 kpc found in the halo of M51 is consistent with superbubbles and the Parker instability being the main energy injection mechanisms in galactic halos., Comment: 36 pages, 19 figures, 3 tables. Accepted for publication in ApJ

Both observations and modelling of magnetic fields in the diffuse interstellar gas of spiral galaxies are well developed but the theory has been confronted with observations for only a handful of individual galaxies. There is now sufficient data to consider statistical properties of galactic magnetic fields. We have collected data from the literature on the magnetic fields and interstellar media (ISM) of 20 spiral galaxies, and tested for various physically motivated correlations between magnetic field and ISM parameters. Clear correlations emerge between the total magnetic field strength and molecular gas density as well as the star formation rate. The magnetic pitch angle exhibits correlations with the total gas density, the star formation rate and the strength of the axisymmetric component of the mean magnetic field. The total and mean magnetic field strengths exhibit noticeable degree of correlation, suggesting a universal behaviour of the degree of order in galactic magnetic fields. We also compare the predictions of galactic dynamo theory to observed magnetic field parameters and identify directions in which theory and observations might be usefully developed., Accepted for publication in ApJ (November 5, 2014); 18 pages, 10 figures (Version 2: Replaced 'regular' with 'ordered' on page 2; Replaced 'regular' with 'large-scale' on page 14.)

We employ an analytical model that incorporates both wavelength-dependent and wavelength-independent depolarization to describe radio polarimetric observations of polarization at $\lambda \lambda \lambda \, 3.5, 6.2, 20.5$ cm in M51 (NGC 5194). The aim is to constrain both the regular and turbulent magnetic field strengths in the disk and halo, modeled as a two- or three-layer magneto-ionic medium, via differential Faraday rotation and internal Faraday dispersion, along with wavelength-independent depolarization arising from turbulent magnetic fields. A reduced chi-squared analysis is used for the statistical comparison of predicted to observed polarization maps to determine the best-fit magnetic field configuration at each of four radial rings spanning $2.4 - 7.2$ kpc in $1.2$ kpc increments. We find that a two-layer modeling approach provides a better fit to the observations than a three-layer model, where the near and far sides of the halo are taken to be identical, although the resulting best-fit magnetic field strengths are comparable. This implies that all of the signal from the far halo is depolarized at these wavelengths. We find a total magnetic field in the disk of approximately $18~\mu$G and a total magnetic field strength in the halo of $\sim 4-6~\mu$G. Both turbulent and regular magnetic field strengths in the disk exceed those in the halo by a factor of a few. About half of the turbulent magnetic field in the disk is anisotropic, but in the halo all turbulence is only isotropic., Comment: Accepted for publication in Astronomy & Astrophysics, 10 pages, 5 figures, 5 tables

Using high-resolution data of the linearly polarized intensity and polarization angle at 3.6, 6.2, and 20 cm together with a 3-D model of the regular magnetic field, we study variations of the structure, strength, and energy density of the magnetic field in the Scd galaxy M33. The regular magnetic field consists of a horizontal component (represented by an axisymmetric mode from 1 to 3 kpc radius and a superposition of axisymmetric and bisymmetric modes from 3 to 5 kpc radius) and a vertical component. However, the inferred `vertical field' may be partly due to a galactic warp. We estimate the average total and regular magnetic field strengths as ~ 6.4 and 2.5 $\mu$G, respectively. Generation of interstellar magnetic fields by turbulent gas motion in M33 is indicated as the turbulent and magnetic energy densities are about equal., Comment: 2 pages, 1 figure, in the proceedings of the IAU Symposium 259: "Cosmic magnetic fields: from planets, to stars and galaxies", Teneriffe, November 2008, in press

We calculate the relative magnitudes of the fluctuations in total synchrotron intensity in the interstellar medium, both from observations and from theory under various assumptions about the correlation or anticorrelation between cosmic rays and interstellar magnetic fields. The results are inconsistent with local energy equipartition between cosmic rays and magnetic fields. The distribution of cosmic rays must be rather uniform at scales of order 1 kpc, whereas interstellar magnetic fields vary at much smaller scales.

To the Editor: Over the past two decades, testing for eosinophiluria has gained widespread acceptance as a means of screening for acute interstitial nephritis. The frequent use of this test may be explained, in part, by the subtle clinical presentation of this condition (fever, rash, arthralgia, and renal failure), which mimics other entities, such as pyelonephritis and renal manifestation of various systemic diseases. Renal biopsy, although used infrequently to diagnose acute interstitial nephritis, continues to be the gold standard. The data on urinary eosinophil testing are inconsistent. A report in the Journal in 1986 by Nolan et al.1 states that . . .

Background The End of Life Care Strategy (2008) states: ‘high quality services should be available in all locations, including prisons,’ and recommends collaborative working across the prisons, coronial, healthcare and specialist palliative care services. Aims and Methods The aim of the study was to explore experiences of physicians working in specialist palliative care, in caring for prisoners and their views about facilitators and barriers, to providing high quality care. An online questionnaire was distributed to members of the Association of Palliative Medicine of Great Britain and Ireland. Results Two hundred and thirty-six completed questionnaires (23.3% response rate). One hundred and thirty-seven (58.1%) respondents had experience of caring for prisoners. The most common reasons for review included pain control (23.6%), symptom control (27.6%) and end of life care (20.5%). The interface between services in prisons was identified as complex by 173 (73.3%) of respondents–impacting on delivery of care, requiring a comprehensive interface between staff inside and specialist palliative care services outside the prison. Ninety-six (39.4%) respondents were willing to be involved in the delivery of an education programme and 128 (54.2%) were keen to learn about prison structures and healthcare. Ninety respondents were unsure if end of life care tools could be implemented within prisons. Conclusions There are consistent perceptions regarding factors that enhance palliative and end of life care in prisons. These include the need to develop working relationships, and enhance communication, within the prison as well as between the prison and outside agencies. The development of education and research, management of public perceptions and the review of policies, procedures and legal issues were highlighted. There is willingness by physicians to engage with the prison service to develop and support palliative and end of life care. Strategic development at local and national level is important due to the unique characteristics of each prison.

Introduction The number of older prisoners in the UK has more than doubled in the last decade, with the greatest increases amongst those over 70. Around 40% of older prisoners are sex offenders, many of whom are in prison for the first time due to historic abuse. Longer sentences and more stringent release criteria mean that increasing numbers of anticipated deaths in prison are predicted. Prison staff experience tensions between care and custody and demands for considerable emotional labour in delivering palliative care to such prisoners. Aim(s) and method(s) This paper presents some of the methodological challenges encountered during the early stages of the ‘Both sides of the fence’ study, which uses action research to develop a transferable model of integrated palliative care for prisoners. The first phase comprises a detailed situational analysis to explore current palliative care provision in one prison; then healthcare and custodial staff participate in action cycles to implement and evaluate changes to practice. Results A prison with a large population of older and disabled prisoners was identified as the research site, and access was granted following ethical and governance approvals. Engagement of diverse groups of staff in the research required multiple meetings, extensive networking and the visible on-site presence of the researcher; this engagement led to an important protocol amendment to include focus groups with prisoners who provide informal care to fellow prisoners. Conclusion(s) Establishing effective connections with a wide range of prison staff has been key to overcoming the methodological challenges and progressing the research.

Background The End of Life Care Strategy (2008) states that healthcare providers, prisons and coronial services should develop strategies that enhance delivery of palliative and end of life care. The prison environment and rules potentially creates inequalities in care. A paucity of research means that although palliative care is recognised as desirable, there is a lack of evidence about the nature of what is required and its feasibility in a prison context. Aims and Methods The aim of the study was to quantify palliative and end of life care need in adult prisons in England and Wales and identify services delivered and strategies to enhance care. A self-reported questionnaire was developed and consent for participation sought from 124 prisons. Results Data obtained from 39 prisons (31.5% response rate) indicate that between 2010-2012, 113 prisoners died from natural causes; retrospective review concluded that 68 required palliative care input. Forty-five were considered for release to receive care in an alternative location; 20 of them were released. Factors preventing release included on-going risk, failure to identify patients in a timely manner or obtain the required medical report, and prisoners9 wishes to remain in prison. Two-thirds of prisons had a palliative care policy; 28% had implemented the Gold Standards Framework and 36% Advance Care Planning. Ninety percent of prisons had access to palliative care nurse specialists and 77% palliative medicine consultants. Three broad approaches were identified; the individual prison approach, the cluster approach and the regional approach. Conclusions There is evidence of support from specialist palliative care services, implementation of palliative care principles and access to education for prison staff. The study has highlighted the challenges in developing palliative care services across the entire prisons service and the unique approaches adopted. Further research is underway to develop a model of integrated palliative and end of life care for dying prisoners.

The λ6 cm radio continuum emission from the barred galaxy NGC 2442 displays several unusual features that are probably due to the interaction of the galaxy with the intergalactic medium.

Introduction The End of Life Care Strategy (2008) states: ‘high quality services should be available in all locations, including prisons’. Prisons have characteristics which potentially create inequalities in the delivery of care. A paucity of research means that the need for palliative and end of life care in prisons has not been established. Aims and Methods To quantify palliative and end of life care need, in adult prisons and identify strategies for enhancing care. A self-reported questionnaire was developed and distributed to 124 prisons. Results Data obtained from 39 prisons (31.5% response rate), revealed that between 2010–2012, 68 prisoners required palliative care, 45 were considered for release to receive care in alternative locations, of which 20 were released. Factors preventing release included ongoing risk, failure to identify patients in a timely manner, and prisoners9 wishes to remain in prison. Two-thirds of prisons had a palliative care policy; 28% had implemented the Gold Standards Framework; 54% the Liverpool Care Pathway or equivalent and 36% Advance Care Planning. Ninety percent of prisons had access to palliative care nurse specialists and 77% palliative medicine consultants. Conclusions The number of prisoners requiring palliative care is larger than expected. Although there is evidence of palliative care support and principles available, work is still required to ensure equity in end of life care provision for prisoners. Further research in this area, funded by Marie Curie Cancer Care, will begin in 2013.

Relative radiometric normalization (RRN) to remove sensor effects, solar and atmospheric variation from at-sensor radiance values is often necessary for effective detection of temporal change. Traditionally, pseudo-invariant features (PIFs) are chosen subjectively, where as an analyst manually chooses known objects, often man-made, that should not change over time. An alternative method of selecting PIFs uses a principal component analysis (PCA) to select the PIFs. We compare the two RRN methods using PIFs in multiple Landsat images of urban and rural areas in Australia. An assessment of RRN quality was conducted including measurements of slope, root mean square error, and normalized difference vegetation index. We found that in urban areas both methods performed similarly well. However, in the rural area the automated PIF selection method using a PCA performed better due to the rarity of built features that are required for the manual PIF selection. We also found that differences in performance of the manual and automated methods were dependent on the accuracy assessment method tested. We conclude with a discussion on the relative merits of different RRN methods and practical advice on how to apply the automated PIF selection method.

Background Corticosteroids are used within specialist palliative care for a variety of indications, from wellbeing to medical emergencies such as spinal cord compression. For benefits to outweigh toxicity, it has been suggested that they should be used according to defined guidelines. Aim The NorthWest Audit Group aimed to review the practice of organisations across the Northwest of England regarding corticosteroid use. Method This multi-centre, cross-regional, retrospective case-note audit used a standardised data collection tool to gather information on patients with advanced malignancy, known to specialist palliative care. A multi-professional steering group developed standards of good practice against which the first 2 weeks of steroid therapy was audited. Results Data were collected on 181 patients from 22 sites including hospital, hospice and community settings. Specialist palliative care professionals were involved in the commencement of steroids in 63%. The indication was documented in 82%, with most commonly cited reasons being anorexia, pain, fatigue and raised intracranial pressure. Previous steroid use was documented in 18%. When patients were prescribed medications that interact with corticosteroids, 4/21 (19%) had evidence of this being taken into consideration. Instructions for blood sugar monitoring were present in 24%. Where there was concurrent aspirin or NSAID use, gastro-protection was prescribed in 36/41 cases (87%). For patients remaining in the same care setting, there was evidence of a dose review in 79%. For those who were discharged from the service, there was a plan for future monitoring in 58%. Conclusion This audit was well received with a very positive return. It demonstrated scope for improvement in current practice. Issues highlighted include the need for improvement in documentation of previous steroid use, instructions for blood sugar monitoring and review of drug interactions. Communication is vital when a patient is transferred between services so that monitoring of safety and efficacy is on-going.

Background The ability of sugarcane to accumulate high concentrations of sucrose in its culm requires adaptation to maintain cellular function under the high solute load. We have investigated the expression of 51 genes implicated in abiotic stress to determine their expression in the context of sucrose accumulation by studying mature and immature culm internodes of a high sucrose accumulating sugarcane cultivar. Using a sub-set of eight genes, expression was examined in mature internode tissues of sugarcane cultivars as well as ancestral and more widely related species with a range of sucrose contents. Expression of these genes was also analysed in internode tissue from a high sucrose cultivar undergoing water deficit stress to compare effects of sucrose accumulation and water deficit. Results A sub-set of stress-related genes that are potentially associated with sucrose accumulation in sugarcane culms was identified through correlation analysis, and these included genes encoding enzymes involved in amino acid metabolism, a sugar transporter and a transcription factor. Subsequent analysis of the expression of these stress-response genes in sugarcane plants that were under water deficit stress revealed a different transcriptional profile to that which correlated with sucrose accumulation. For example, genes with homology to late embryogenesis abundant-related proteins and dehydrin were strongly induced under water deficit but this did not correlate with sucrose content. The expression of genes encoding proline biosynthesis was associated with both sucrose accumulation and water deficit, but amino acid analysis indicated that proline was negatively correlated with sucrose concentration, and whilst total amino acid concentrations increased about seven-fold under water deficit, the relatively low concentration of proline suggested that it had no osmoprotectant role in sugarcane culms. Conclusions The results show that while there was a change in stress-related gene expression associated with sucrose accumulation, different mechanisms are responding to the stress induced by water deficit, because different genes had altered expression under water deficit.

Andrew Fletcher introduces National Childminding Week 2010, and one childminder explains how she uses music to benefit the children in her setting.

There has never been a better time for home-based childcarers to have a major influence on their profession moving forward, with National Childminding Week following the May 6 general election.

Andrew Fletcher introduces a project set up to support and develop speech and communication skills.

The profile of childminders has been rising steadily in recent years, despite a fall in numbers, and with an election looming, the NCMA has five key aspirations for the profession in the coming year.

Andrew Fletcher explains how NCMA is supporting childminders to advertise their setting.

At present, grandparents can only remain as a registered childminder, if they look after other children in addition to their own grandchildren. NCMA, however, believes this short-term attitude is wrong.

Andrew Fletcher reviews the Early Years Foundation Stage and this month’s case study gives her view of how the framework works in practice.

Registered childminders have consistently shown that they are able to deliver the free entitlement, however, to continue this good progress, we will need networks to be set up in all local authorities.

Do you have places to fill? Andrew Fletcher, joint chief executive of the National Childminding Association, gives some tips on marketing your setting and this month’s case study provides some ideas for fun days out.

Originally conceived by R McMinn, emeritus professor of anatomy at the University of London, the Clinical Atlas of Human Anatomy was revolutionary from the outset. Seeking to take advantage of recent technical advances in colour photography, McMinn utilised the photographic expertise of Ralph Hutchings, who at that time was working as a photographic technician and the chief medical laboratory officer at the Royal College of Surgeons of England. Together they produced the first colour photographic atlas of human anatomy, using dissected human cadaveric specimens obtained mainly from the extensive collection held in the college’s anatomy museum. The atlas was first published …

The large amounts of nitrogen (N) fertiliser applied to most cropping systems support high yields but cause N pollution. More efficient use of N in cropping systems can be achieved through improved N management practices combined with genetic improvement of the crop. The magnitude of genetic variation in sugarcane (Saccharum officinarum L.) for internal nitrogen use efficiency (iNUE, biomass produced per unit tissue N) was investigated as this could provide a basis for breeding varieties with reduced N demand. Genotypes of a mapping population were examined for biomass production and physiological variables under low or high N supply in controlled conditions. Key findings were: (i) genotypic variation for biomass production and iNUE was up to 3-fold greater under low than high N supply, (ii) elite parent Q165 was among the best performing genotypes for biomass and iNUE at high N but not at low N supply, and (iii) several genotypes had high iNUE at both N supplies. While glutamine synthetase (GS; EC 6.3.1.2) activity has been linked with grain yield in other crops, no direct relationship was observed between whole tissue GS activity and vegetative biomass or iNUE in sugarcane genotypes. Soluble protein content was negatively correlated with iNUE and biomass production. This study demonstrates that there is considerable genetic variation for iNUE in sugarcane, which can be exploited for breeding. It is proposed that breeding programs should assess genotypes not only at high N, but also at low N supply rates to select genotypes that produce high biomass with low and high N supply.

We present the results of a study into the incorporation of fluorine into the mercurocuprate superconductors. In all cases, the effect of fluorination has been to increase the Tc of underdoped superconductors to the maxima reported. This has important ramifications for the role of the interstitial oxygen in the mercurocuprate superconductors. To assist us in our study, we have, additionally, developed a novel synthetic procedure for preparing HgBa2CuO4+δ in a highly underdoped state. Remarkably, this material shows an increase in Tc, upon fluorination, of 60K!