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Recognition of peatlands as a key natural store of terrestrial carbon has led to new initiatives to protect and restore them. Some afforested bogs are being clear-felled and restored (forest-to-bog restoration) to recover pre-afforestation ecosystem function. However, little is known about differences in the peat properties between intact, afforested and restored bogs. A stratified random sampling procedure was used to take 122 peat cores from three separate microforms associated with intact (hollows; hummocks; lawns), afforested and restored bogs (furrows; original surface; ridges) at two raised and two blanket bog locations in Scotland. Common physical and chemical peat properties at eight depths were measured in the laboratory. Differences in bulk density, moisture and carbon content between the afforested (mean = 0.103 g cm−3, 87.8% and 50.9%, respectively), intact (mean = 0.091 g cm−3, 90.3% and 51.3%, respectively) and restored bogs (mean = 0.095 g cm−3, 89.7% and 51.1%, respectively) were small despite their statistical significance. The pH was significantly lower in the afforested (mean = 4.26) and restored bogs (mean = 4.29) than the intact bogs (mean = 4.39), whereas electrical conductivity was significantly higher (mean: afforested = 34.2, restored = 38.0, intact = 25.3 μS cm−1). While significant differences were found between treatments, effect sizes were mainly small, and greater differences in pH, electrical conductivity, specific yield and hydraulic conductivity existed between the different intact bogs. Therefore, interactions between geographic location and land management need to be considered when interpreting the impacts of land-use change on peatland properties and functioning.

Forests are often considered to be able to play a significant role in tackling global warming. To fully understand their potential in mitigating climate change and to develop more accurate ecosystem GHG flux budgets and process-based models of forests, we require more knowledge of methane (CH4) and nitrous oxide (N2O) exchange in forests, their underlying processes, environmental controls and responses to forest management. In recent years, it is becoming evident that not only soils but also the trees themselves may significantly contribute to CH4 and N2O fluxes in forest ecosystems.Our research mainly focussed on greenhouse gas (GHG) exchange in temperate UK forests on both mineral and organic soils. We will primarily concentrate on CH4 fluxes as N2O fluxes were often relatively low in these forests and, by including CO2 fluxes, we will put them into the context of the overall ecosystem GHG exchange. A range of flux methods at different scales were used in our field studies to be able to capture the often high temporal and spatial variability of the GHG exchange between the atmosphere and either soils, tree stems or entire trees aboveground, and to identify potential drivers of the fluxes. The impact of management practices including clear fell, drainage and the resulting micro-topography, and forest-to-bog restoration on CH4 fluxes from organic soils following the first forest rotation will also be described. We regularly used novel automated and chamber approaches and technologies, and the advantages and limitations of the different flux approaches and their use to upscale fluxes to the landscape scale will be evaluated.

The carbon sequestration potential of peatlands has led to increasing interest in the restoration of bogs previously subjected to plantation forestry. However, little information exists about the effects on hydrological processes of what has become known as forest-to-bog restoration. The hydrological functioning of three afforested, two intact and four forest-to-bog restoration sites was compared at a raised bog and blanket bog location. For the raised bog location, the annual runoff/rainfall coefficient was 59.7% for the intact site, 41.0% for the afforested site and 53.1% for the oldest restoration site (9 years post-felling). At the blanket bog location, the coefficient was 80.6% for the intact site, 63.0% for the afforested site and 71.6% for the oldest restoration site (17 years post-felling). Compared with intact bog, median peak storm discharge was significantly greater in the restoration sites for the raised bog location but not for the blanket bog location. Water-table peak lag times were greatest, and water-table depths deepest in the afforested sites and the most recent raised bog restoration site and least in the oldest blanket bog restoration site. The estimated contribution of overland flow in the afforested sites was 2.9% for the raised bog and 11.9% for the blanket bog, increasing to 8.7% and 32.2% at the oldest restoration sites for the raised bog and blanket bog, respectively. Overall, hydrological functioning of the raised bog and blanket bog restoration sites was different from the intact sites but was most similar to intact bog in the oldest restoration sites.

Ombrotrophic, naturally open peatlands are increasingly susceptible to invasion by scrub and trees due to human disturbance, N deposition and climate change. There is limited research on the effect these trees have on ecosystem functions and their removal can be costly, making decisions over best management practice challenging. The adverse growing conditions associated with many of these peatlands can result in stunted tree growth meaning that complete enclosure of a tree remains a practical possibility. In this study we aim to quantify the CH4 and CO2 fluxes from whole trees growing on a disturbed peatland and assess their significance relative to the fluxes between the vegetated peat surface and atmosphere. We also aim to identify if the establishment of trees impacts CH4 and CO2 fluxes from the vegetated peat surface, as compared to adjacent uninvaded peatland.We have developed a removable chamber capable of enclosing whole trees of up to 3 metres high, making it suitable for use on juvenile or stunted trees. Being able to enclose an entire tree removes potential errors caused by estimating whole tree fluxes by upscaling measurements from a subsample of tree surfaces. The chamber is constructed with a transparent membrane and removable cover so that light and dark measurements can be taken. We use the chamber to take CH4 and CO2 flux measurements on a site with approximately 20-year-old silver birch trees (Betula pendula) of an average height of 2-3 metres. Flux measurements have been taken from the trees and ground collars at different times of year. We have also studied diurnal variation.Our initial results have shown that the trees on our site are emitters of CH4, although this emission is small in comparison to that produced by the rest of the habitat. The vegetated peat surface in the wooded area had lower CH4 emission but reduced CO2 uptake as compared to the open area. The diurnal study on one tree indicates that methane emissions increase at night. A further diurnal study is planned to explore this further. This study extends the limit on the size of vegetation that can be sampled by a manually operated flux chamber.

Afforestation is a significant cause of global peatland degradation. In some regions, afforested bogs are now undergoing clear-felling and restoration, often known as forest-to-bog restoration. We studied differences in water-table depth (WTD) and porewater chemistry between intact, afforested, and restored bogs at a raised bog and blanket bog location. Solute concentrations and principal component analysis suggested that water-table drawdown and higher electrical conductivity (EC) and ammonium (NH4-N) concentrations were associated with afforestation. In contrast, higher dissolved organic carbon (DOC) and phosphate (PO4-P) concentrations were associated with deforestation. Drying-rewetting cycles influenced seasonal variability in solute concentrations, particularly in shallower porewater at the raised bog location. WTD was significantly deeper in the oldest raised bog restoration site (~9 years post-restoration) than the intact bog (mean difference = 6.2 cm). However, WTD in the oldest blanket bog restoration site (~17 years post-restoration), where furrows had been blocked, was comparable to the intact bog (mean difference = 1.2 cm). When averaged for all porewater depths, NH4-N concentrations were significantly higher in the afforested than the intact sites (mean difference = 0.77 mg L−1) whereas significant differences between the oldest restoration sites and the intact sites included higher PO4-P (mean difference = 70 μg L−1) in the raised bog and higher DOC (mean difference = 5.6 mg L−1), EC (mean difference = 19 μS cm−1) and lower SUVA254 (mean difference = 0.13 L mg−1 m−1) in the blanket bog. Results indicate felled waste (brash) may be a significant source of soluble C and PO4-P. Mean porewater PO4-P concentrations were between two and five times higher in furrows and drains in which brash had accumulated compared to other locations in the same sites where brash had not accumulated. Creating and maintaining brash-free buffer zones may therefore minimise freshwater impacts.

There has been increasing interest in peatlands over the last two decades after their recognition as a primary worldwide carbon store and potential to mitigate climate change. Afforestation is a significant global source of peatland degradation, and concentrated efforts to restore affected peatlands are ongoing. Our study monitored the pore-water quality, with respect to the water table depth (WTD), over 18 months from a raised bog and a blanket bog study site where the first forest-bog restoration work started in 2002. We collected pore-water samples from 4 small, hydrologically disconnected catchments which included intact forestry, a near-natural bog and two restored catchments of differing ages and restoration techniques, at each of the study sites. The WTD was significantly different between the afforested catchments (deepest) and near-natural bog (shallowest), increasing with time since restoration for the restored catchments at both study sites. In periods of low rainfall, the WTD receded faster at the raised bog site, which may be because of the increased water demand from more mature tree stands. There were significant spatial and temporal variations in pore-water chemistry. However, dissolved organic carbon (DOC) and soluble reactive phosphate (PO4-P) concentrations were significantly higher than the near-natural bog (difference in means of 30.37 mg L-1 and 412 µg L-1, respectively), 5-6 years after restoration. DOC and PO4-P concentrations reduced with time since restoration, and, at the blanket bog site, there was no significant difference between the near-natural bog and a catchment that had been restored 17 years earlier. Principal component analysis (PCA) showed that DOC, PO4-P and nitrite (NO2-N) concentrations are controlled by similar processes and primarily a component of the restoration work; dissolved ammonium (NH4-N), water table depth and electrical conductivity were more closely associated with afforestation. Higher NH4-N concentrations within the forest pore-water are likely because of increased mineralisation rates within the peat after a lowering of the WTD through drainage and the water demands from the trees; increased electrical conductivity is likely connected to atmospheric scavenging from forest canopies. The lowland raised bog site had significantly higher mean DOC concentrations which we hypothesise could be a result of increased plant production or the hydrological differences between lowland raised bog and blanket bogs. The humic fractions of the DOC, measured by the E4:E6 ratio of absorption, were significantly higher in the restored sites of the raised bog and negatively correlated with the depth to the water below the surface. We found significant differences between the afforested microforms (furrows, original surface and ploughed ridges) for many of the pore-water variables measured, and we believe newly developed ground smoothing techniques could help restore the natural balance. Dominant vegetation cover was also a significant factor, and other methods such as plug planting of bog species could be beneficial.

Satellite Earth Observation (EO) is often used as a cost-effective method to report on the condition of remote and inaccessible peatland areas. Current EO techniques are primarily limited to reporting on the vegetation classes and properties of the immediate peat surface using optical data, which can be used to infer peatland condition. Another useful indicator of peatland condition is that of surface motion, which has the potential to report on mass accumulation and loss of peat. Interferometic SAR (InSAR) techniques can provide this using data from space. However, the most common InSAR techniques for information extraction, such as Persistent Scatterers’ Interferometry (PSI), have seen limited application over peat as they are primarily tuned to work in areas of high coherence (i.e., on hard, non-vegetated surfaces only). A new InSAR technique, called the Intermittent Small BAseline Subset (ISBAS) method, has been recently developed to provide measurements over vegetated areas from SAR data acquired by satellite sensors. This paper examines the feasibility of the ISBAS technique for monitoring long-term surface motion over peatland areas of the Flow Country, in the northeast of Scotland. In particular, the surface motions estimated are compared with ground data over a small forested area (namely the Bad a Cheo forest Reserve). Two sets of satellite SAR data are used: ERS C-band images, covering the period 1992–2000, and Sentinel-1 C-band images, covering the period 2015–2016. We show that the ISBAS measurements are able to identify surface motion over peatland areas, where subsidence is a consequence of known land cover/land use. In particular, the ISBAS products agree with the trend of surface motion, but there are uncertainties with their magnitude and direction (vertical). It is concluded that there is a potential for the ISBAS method to be able to report on trends in subsidence and uplift over peatland areas, and this paper suggests avenues for further investigation, but this requires a well-resourced validation campaign.

Peatlands are one of the largest terrestrial stores of carbon. Carbon exchange in peatlands is often assessed solely by measurement of contemporary fluxes; however, these fluxes frequently indicate a much stronger sink strength than that measured by the rate of C accumulation in the peat profile over longer timescales. Here we compare profile-based measurements of C accumulation with the published net ecosystem C balance for the largest peatland area in Britain, the Flow Country of northern Scotland. We estimate the long-term rate of C accumulation to be 15.4 g C m−2 yr−1 for a site where a recent eddy covariance study has suggested contemporary C uptake more than six times greater (99.37 g C m−2 yr−1). Our estimate is supported by two further long-term C accumulation records from nearby sites which give comparable results. We demonstrate that a strong contemporary C sink strength may not equate to a strong long-term sink and explore reasons for this disparity. We recommend that contemporary C sequestration should be viewed in the context of the long-term ecological drivers, such as fires, ecohydrological feedbacks and the changing quality of litter inputs.

Triariodes Clark and Anderson, new genus, is described, and Triarius vittipennis (Horn, 1893), new combination, is transferred to this genus. Triariodes admiratio Clark and Anderson, new species, Triariodes segonku Clark and Anderson, new species, and Triarius novoleonis Clark and Anderson, new species, are described from Mexico. Triarius texanus Clark and Anderson, new species, is described from Texas. All known species in Triariodes and Triarius are diagnosed, illustrated, and included in keys to species. Diabrotica neotropica Clark and Anderson is proposed as a replacement name for Triarius tropicusWeise, 1921.

The authors take up Amy Allen's suggestion that while Foucault's work may be able to support a certain type of self-critique and self-development, it does not permit the kind of interpersonal relations that are necessary for the development of intersubjective meaning in struggles against imposed identities. The authors contend that for Foucault, relations of ‘truth’ play an important constitutive role in subjectivities, and that understanding the ‘politics of ourselves’ in the context of this truth shows not only an openness to meaningful interpersonal relations, but also that these relations are capable of generating the conceptual and normative resources necessary for resisting socially imposed subjectivities. The authors present such an account of intersubjective relations based on Foucault's discussion of parrhesia, and develop a model of collaborative political action that addresses the criticisms raised.

Summary 1. Edge effects of native forest fragmentation have been well studied, but there are few studies of open-ground habitats fragmented by plantation forests. We measure forestry edge effects on open-ground breeding birds, following one of Europe’s biggest and most controversial land-use transformations. 2. The ‘Flow Country’ of northern Scotland is one of the world’s greatest expanses of blanket bog. It became fragmented by conifer forests planted in the late 20th century, and these now adjoin open peatlands protected under European conservation legislation. Detrimental edge effects on breeding birds were anticipated, but not apparent shortly after planting. 3. Using survey data collected in 2003–2006, and logistic regression modelling, we tested whether breeding distributions of three wader species of international conservation concern, dunlin, European golden plover and common greenshank, were influenced by distance to forest edge, controlling for habitat and topography. 4. All three species were more likely to occupy flatter, more exposed ground close to bog pools and were influenced by peatland vegetation structure. There was an additive and adverse effect of proximity to forest edge for dunlin and European golden plover, but not common greenshank. This effect was strongest within 700 m of forest edges. We used these results to predict which areas should benefit most from removal of adjacent forestry and so guide maintenance and restoration of the bird interests of the protected areas. 5. Synthesis and applications. Edge effects of mature forestry on dunlin and golden plover are apparent over several hundred metres and are now being used to guide forest planning in northern Scotland. The scale of edge effect is broadly consistent with other avian studies in open-ground habitats across Eurasia and North America, so buffer zones of this order are consistent with possible impacts of plantation forestry on open-ground habitats of bird conservation interest. Given renewed interest in conifer afforestation as a climate change mitigation measure, an improved understanding of edge effects and the mechanisms through which they operate is vital to managing plantation forestry in ways that maintain open-ground landscapes of high conservation value.

Introduction Restoration of afforested peatlands was initially driven by recognition of the high biodiversity value and increasing scarcity of peatlands in their natural state. Now we recognise that peatlands also play an important role in climate regulation, raising the question: should we be restoring afforested peatlands on a large scale as a climate change mitigation measure? This needs careful consideration because it involves sacrificing the initial investment in afforestation and taking land out of economic production. And what if we realise when it's too late that the peatland forests were benefiting us in previously unrecognised ways? We need to consider all the goods and services that afforested peatlands provide and weigh these up against those they will supply if we restore them. This chapter provides the background to the restoration of afforested peatlands, looks at the scientific evidence on how afforestation and restoration affect ecosystem services, summarises lessons learned from practical projects and attempts to answer the question: should we be doing more of this in future? The chapter focuses on temperate and boreal peatlands. Tropical peatlands are dealt with in Chapter 14 of this book. This chapter deals with the restoration of naturally forested peatlands that have had the growth of their natural tree cover boosted by forest drainage (forestry-drained peatlands) and naturally treeless peatlands that have been afforested by planting (afforested peatlands). Much of it also applies to peatlands that have become forested naturally as a result of drainage or peat cutting (sometimes also termed ‘afforested’). There are two main contexts reflecting differing degrees of natural tree cover on mires and different peatland forestry practices. In the northern coniferous forest or boreal zone, some mire types have a natural cover of slow-growing trees. During the twentieth century, in Finland, Sweden, Norway, the Baltic countries, Russia, and to a lesser extent in Canada and the United States, forest drainage was undertaken on these wooded peatlands to stimulate growth of the existing tree cover and thus form productive forest stands. Drainage for forestry has been the most extensive use of boreal peatlands, affecting more than 15 million hectares, 90% of which is in Scandinavia or Russia (Paavilainen and Paivanen 1995).

Sustainable peatland management has recently risen up the UK political agenda as links between peatland ecosystem services and key political priorities, such as rural livelihoods, agricultural production, biodiversity conservation, and carbon emissions, have become established. By adopting an ecosystem approach, something that has become internationally advocated through the Convention on Biological Diversity, to understanding the objectives and sustainability of UK peatland management, this paper reviews contemporary policies relating to three broad categories of peatland ecosystem service (provisioning; regulating and cultural), developed at multiple levels (global to local). We highlight problems associated with incomplete knowledge about complex peatland ecosystem processes and disconnected policies and strategies. The review concludes by discussing the kinds of integrated land use policies that are beginning to emerge in the UK and may shape future peatland management.

Summary Habitat networks have an important role in combating the deleterious effects of habitat fragmentation on biodiversity. This paper demonstrates how focal species modelling can be used to help predict the effects of land use change on habitat networks in western oceanic landscapes. The modelling was applied to the Isle of Mull in Western Scotland using three focal species: Pseudocyphellaria norvegica (Gyeln.) P. James, a lichen of native broadleaved woodland; marsh fritillary ( Eurodryas aurinia Rottemburg), a butterfl y of damp grassland and song thrush ( Turdus philomelos CL Brehm), an avian habitat generalist. Signifi cant areas of planted conifer forest on Mull will be converted to open ground habitat and native woodland. These land use changes, together with modest expansion of native woodland, are predicted to have a positive impact on networks for the lichen and marsh fritillary without unduly compromising networks for habitat generalists. There may be scope therefore for a more ambitious strategy for developing native woodland and damp grassland networks, but further testing using focal species with more exacting ecological requirements is desirable. Focal species modelling has value in informing strategies for land use change and the development of habitat networks provided that care is taken to select species with relevant ecological requirements.

BACKGROUND The rapid market expansion of filler treatment options requires physicians and health care providers to fully understand differences among comparable products. OBJECTIVE The objective was to compare commercially available polymethylmethacrylate (PMMA)-based soft tissue fillers to determine if there are meaningful variations in these products that could result in significantly different therapeutic profiles, especially with respect to safety. METHODS AND MATERIALS PMMA particles were evaluated for size and morphology using scanning electron microscopy (SEM) techniques. PMMA microsphere soft tissue filler products from the United States, Europe, Brazil, and Canada were compared with respect to size, homogeneity/irregularity, surface smoothness/roughness, and the presence or absence of sediment and particulate debris. RESULTS Marked differences with respect to PMMA particle morphology and related particle characteristics from a variety of products were found. Of note, some products demonstrated potentially concerning significant variability in particle size and irregular morphology. CONCLUSION It is anticipated that the variability detected in these products, based on the literature, could result in different therapeutic profiles, especially with respect to safety. Physicians and health care providers should be aware that "comparable" products that at a glance appear similar may not be equal.

By modeling salient features of the corticothalamic system over multiple spatial and temporal scales, physiologically based neural field theory has yielded numerous successful predictions that interrelate stimuli, neural activity, and measurements. Likewise, physiologically based neural mass theories of the brainstem-hypothalamus sleep-wake switch and associated systems have recently been developed and shown to quantitatively reproduce a wide variety of arousal-state phenomena. In both cases, model parameters have been independently constrained, and each model has integrated multiple phenomena and measurements into a single unified framework, thereby validating the modeling approach and enabling these features to be interrelated and interpreted in terms of underlying physiology and anatomy. Here, a first integration of the corticothalamic and arousal-state models is carried out by incorporating a simple model of their couplings: upward via the neuromodulatory effects of the ascending arousal system, and downward via the gating of light inputs by higher-level behavior. The resulting “working brain” system has a neural-mass-like limit, governed by delay differential equations that enable it to respond correctly to light-dark cycles, sleep deprivation, jetlag, and pharmacological inputs, while driving the corticothalamic system into parameter regions where it reproduces associated electroencephalograms, evoked response potentials, and other phenomena, whose properties are further elucidated by retaining the appropriate neural field equations. Overall, the combined model provides a simple, highly flexible framework for quantitatively modeling a variety of mesoscale to macroscale brain phenomena, ranging from normal behaviors to highly nonlinear dynamics such as found in seizures, and for examining interactions between such phenomena. these findings are illustrated with representative examples. Fitting of the model to data can be used to infer brain states and underlying parameters.

The Wallerawang colliery, located 15 km north of Lithgow in the western coalfields of NSW, utilised a coal fines briquetting (agglomeration) process to aid in site rehabilitation. The project was used to establish a void of approximately 200 000 m 3 for the burial of sulfidic (acid producing) coarse washery reject by turning a waste material into power station fuel. The briquetting process utilised a double roll press to produce approximately 70 000 tonnes per annum of 50 mm diameter briquettes from drained coal tailings (fine coal washery reject) stored within the site tailings dam. To the best of our knowledge, a briquetting project for the reprocessing of coal tailings as a fuel for conventional power stations had not previously been successfully operated. With extensive energy resources stored within coal tailings dams worldwide and the difficulties sometimes encountered with tailings dam rehabilitation, the potential for the development and future use of this process is considered large. As such, the project represents an innovative example of the implementation of the principles of Cleaner Production and Ecologically Sustainable Development in the coal mining industry of New South Wales, Australia.

Background: Lip dimensions and their relation to the whole face have been discussed mainly in the dental literature. There have been few attempts to scientifically measure the degree of lip augmentation, regardless of method. Objectives: The authors describe a Lip Index that will allow reliable, quantitative analysis of the human lip complex, which is necessary to assess the efficacy and duration of attempts at lip augmentation. Methods: The authors developed a Lip Index as the basis for objective measurements of the effect and duration of lip augmentation with dermal fillers. Measurements may be taken directly from the patient, from standardized photos, or from the computer screen. Using a metric ruler, the height of the vermilion in the middle of the Cupid’s bow is first measured (in mm) on the frontal view. The point of maximum protrusion of the vermilion is then measured (in mm) on a standardized side view perpendicular to a vertical line connecting the base of the columella to the fold demarcating lower lip and chin. Vermilion height multiplied by horizontal protrusion directly correlates with the central volume of the lips, upper and lower. Results: The easily applied ruler provided consistent measures before and after the injection of dermal fillers or soft implants. Adding upper and lower lip indices resulted in the Overall Lip Index for each patient, which was found to be approximately 50 in average females of Caucasian descent, about 100 in females of Asian descent, and nearly 200 in females of African descent. Conclusions: The Lip Index allows for the practical evaluation of the clinical effects and duration of dermal filler injectables or implants. Quantitative assessments of results over time are easy to calculate, without the need for complex measurements or sophisticated analyses.

As the first step upon commencing an in-depth data mining analysis, students should become intimately acquainted with the data under study. In this paper, we present a methodology and set of custom tools that we have designed and developed for use in our data mining courses that allows students to efficiently and effectively accomplish this task. The tools create interactive visual presentations of the data, encouraging students to explore the data in search of patterns or relationships that would then be investigated in subsequent steps using sophisticated statistical and machine learning tools.

The potential for minimising anaesthetic gas consumption with a circle absorber system is related to fresh gas flow. This study measured the actual sevoflurane consumption during elective arthroscopy of the knee in 75 ASA I-II patients randomised to three fresh gas flow rates (6, 3, and 1.5 l/min) using sevoflurane and O(2):N(2)O (1:2) after intravenous induction with fentanyl and propofol. A circle absorber system was used with a laryngeal mask airway. Anaesthetic duration, discharge time and postoperative pain did not differ between groups. Sevoflurane consumption was more than doubled with each doubling of fresh gas flow (0.07+/-0.03; 0.16+/-0.05; 0.41+/-0.12 ml sevoflurane/min; for gas flow 1.5, 3, 6 l/min; P

(1965). The Self and the Object World. By Edith Jacobson. New York: International Universities Press, Inc., 1964. 250 pp. The Psychoanalytic Quarterly: Vol. 34, No. 4, pp. 584-613.

An evaluation of the location and nature of occlusal contacts in centric occlusion of 32 adults revealed teeth that had no occlusal contact, no opposing tooth, contact on flat surfaces, contact on one or more inclined planes, and contacts on a combination of flat and inclined planes.

Recently, I have seen several women presenting an extremely severe acute dermatitis of the face, ears, neck and arms. Historically the dermatitis was of acute onset, and clinically it resembled an acute dermatitis seen in sensitivity to hair dye. The history elicited the information that the dermatitis first appeared on the forehead and the ears. It was finally determined that these patients were allergic to brown nylon® hair nets which they purchased at different variety stores. These nylon® hair nets were used for various purposes, such as keeping the hair in place after a wave set or keeping the hair from being mussed up while the patient was sleeping. Strongly positive reactions to patch tests were obtained. The patients were tested with items such as various dyes and nail lacquers, and no cross sensitivities were demonstrated. Patch tests were made on one woman with a nylon® hair

To the Editor.— I have just read "Ischiogluteal Bursitis: The Pain in the Arse" (227:551, 1974) by Swartout and Compere. This syndrome, ischiogluteal bursitis (weaver's bottom), has been described in several editions of Christopher's Minor Surgery (Philadelphia, W. B. Saunders Co). Ischiogluteal bursitis is one of the manifestations of gout and responds to treatment with colchicine, an opiate, and uricosuric drugs. It is well to remember that gout may affect any joint or bursa. I remember because I suffer from gout, and I have sat on weaver's bottom!

To the Editor:— The article "Nodular Vascular Diseases of the Legs," by Montgomery, O'Leary and Barker (The Journal, June 2, p. 335), should not go unchallenged. The authors have attempted to define a new entity, "nodular vasculitis," and to differentiate it from erythema induratum. Because the authors are eminent, there is danger that their conclusions will be accepted and that an ill defined entity will enter the medical nomenclature to confuse all physicians who are not dermatologists. In the differential diagnosis between "nodular vasculitis" and erythema induratum they state that the nodules tend to be more painful in the former and that erythema induratum tends to occur in younger women. These distinctions are not valid, for the nodules of undoubted erythema induratum may be extremely painful and may occur at any age. After analyzing their paper, one must assume that they have really only one point of differentiation between "nodular

In 1942 Cunningham 1 reported on the use of sulfapyridine as a hemostatic agent. He found that after sulfamethylthiazole powder had been instilled into the operative wound after radical external frontal sinusotomy for osteomyelitis of the frontal bone the usual considerable postoperative oozing was absent. This observation led him to experiments on guinea pigs. Circular wounds were made on the backs of the animals, and five to seven days later the scabs were evulsed so that an open granulating and freely oozing surface remained. Powdered sulfapyridine, sulfanilamide, sulfathiazole, sulfamethylthiazole 2 and talc were sprayed on with a powder blower. The wounds treated with sulfamethylthiazole and sulfapyridine exhibited an immediate tendency to hemostasis, while the wounds treated with the other powders and with talc and untreated control wounds all oozed for from five to ten minutes. The sulfapyridine powder was also found to be