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Clogging of streambeds due to clay deposition influences the stream‐subsurface exchange flux and thus directly modulates hyporheic ecological and biogeochemical processes. Clogging of sandy streambeds has previously been studied under losing and gaining flows and during streambed movement, but not when these two flow conditions coincided. We conducted flume experiments to quantify the combined effect of moving bedforms and losing or gaining flows on kaolinite deposition and streambed clogging. The experiments were conducted by adding pulses of kaolinite in a flume packed with sand under a stream water velocity of 25 cm/s. We measured the deposition rates, dynamics of hyporheic exchange flux (HEF) and vertical hydraulic conductivity (Kv), and the vertical distribution of kaolinite at the end of the experiments under two losing and two gaining flows (Darcy velocity of 10 and 20 cm/day). Kaolinite deposition led to clogging and reduction in Kv and HEF under all flow conditions. Deposition occurred faster under losing flow conditions than under gaining flow conditions. However, the changes in Kv and HEF were similar under losing and gaining flow conditions for similar kaolinite concentrations in the bed. Our results indicate that the deposition patterns of kaolinite were more influenced by bedform movement than by losing or gaining flow conditions, which is markedly different from the behavior observed under losing and gaining conditions for stationary bedforms. This implies that bedform morphodynamics control local‐scale clogging of sandy streambeds and should be accounted for when studying the hydrology of catchments at larger scales. Key Points: Bed movement had a greater influence on kaolinite deposition patterns than either losing or gaining flow conditionsKaolinite accumulated in the bed much more quickly under losing conditions than gaining conditions, causing rapid clogging of the bedHydraulic conductivity and hyporheic flux depended on kaolinite content in the bed and were similar under losing and gaining conditions [ABSTRACT FROM AUTHOR]

Fine particles (0.1–100 microns) are ubiquitous within the water column. Observations on the interactions between suspended fine particles and sediment beds remain limited, reducing our ability to understand the interactions and feedbacks between fine particles, morphodynamics, and hyporheic flow. We performed laboratory experiments to explore changes in bedform morphodynamics and hyporheic flow following the progressive addition of kaolinite clay to the water column above a mobile sand bed. We characterized these interactions by taking high‐frequency time series measurements of bed topography and freestream clay concentration combined with solute injections and bed sediment cores to characterize subsurface properties. Deposition of initially suspended clay resulted in a decrease of bedform height, celerity, and sediment flux by 14%, 22%, and 29% when 1000 g was accumulated within the bed (equal to clay/sand mass ratio of 0.4% in the bed). The hyporheic exchange flux decreased by almost a factor of 2 for all clay additions, regardless of the amount of clay eventually deposited in the bed. Post experiment sediment cores showed clay accumulation within and below the mobile layer of the bedforms, with the peak concentration occurring at the most frequent bedform scour depth. These results demonstrate the tight coupling between bed sediment morphodynamics, fine particle (clay) deposition, and hyporheic exchange. Suspended and bed load transport rates are diminished by the transfer of suspended load to the sediment via hyporheic exchange. This coupling should be considered when estimating sediment transport rates. Key Points: Initially suspended fine clay particles within the water column rapidly accumulate within the sediment bed due to hyporheic exchangeFine clay particle storage occurs beneath the mobile layer of the sediment bed defined by the extent of bedform scourFormation of the fine particle layer results in reductions of bedform celerity, height, and sediment flux while length is unchanged [ABSTRACT FROM AUTHOR]

This study establishes why, after centuries as a manorial borough, Kendal was incorporated in 1575 and who brought this change about. It assesses the relationships between the town, its parish and its local region and looks at the impact that the new corporation had on them. These issues are of general importance to incorporations in other towns, especially those which, like Kendal, had previously been dominated by the manorial lord, and where borough self-government was relatively unsophisticated. Of course, there is no space to discuss every aspect of the incorporation here and so the paper concludes by suggesting some further avenues for research in the run up to the 450th anniversary of Kendal's incorporation. [ABSTRACT FROM AUTHOR]

The threshold stress for bed sediment transport exerts a primary control on the geometry and stability of coarse‐grained rivers (diameter ≥ 5 mm). Understanding how riverbed mobility couples to channel form is a key mechanistic link for predicting river response to external perturbations such as land use practices and changing climate. Unfortunately, determination of a representative threshold stress is notoriously difficult in the field. Empirical studies have observed that the critical dimensionless shear (Shields) stress (τ*c) is correlated with channel slope, a property that is substantially easier to estimate. Mechanistic models have been developed to explain the observed correlation; however, limited field data preclude the widespread application of these models. For practical reasons, the empirical regressions between slope and τ*c are utilized as predictive models. Through a large compilation of field data, we demonstrate that there are two significant problems with using the empirical regressions: (1) they are based on a partial sampling of the observed parameter space of coarse‐grained rivers, and (2) they do not capture the covariation between the bankfull Shields stress (τ*bf) and τ*c. These regressions provide spurious predictions for the bankfull transport capacity (τ*bf/τ*c) of gravel‐bed rivers. When site‐specific empirical measurements of τ*c are made, coarse‐grained rivers exhibit a remarkably constant transport capacity that is in close agreement with equilibrium channel theory (τ*bf= 1.2τ*c). From these data we advocate that, in the absence of measurements, τ*c can be reasonably estimated from the τ*bf using equilibrium channel theory. Key Points: In natural rivers critical Shields stress covaries with bankfull Shields stress in a manner predicted by theoryEmpirical relations between slope and critical Shields stress are based on a partial sample of the known parameter space for gravel riversPredictions of changes in bankfull transport capacity based on the correlation between slope and the threshold of motion can be spurious [ABSTRACT FROM AUTHOR]

Ice sintering is a form of metamorphism that drives the microstructural evolution of an aggregate of grains through surface and volume diffusion. This leads to an increase in the grain‐to‐grain contact area (neck) and density of the aggregate over time, resulting in the evolution of its strength, porosity, thermal conductivity, and other properties. This process plays an important role in the evolution of icy planetary surfaces, though its rate and nature are not well constrained. In this study, we explore the model of Swinkels and Ashby (1981, https://doi.org/10.1016/0001‐6160(81)90154‐1) and assess the extent to which it can be used to quantify sintering timescales for water ice. We compare predicted neck growth rates to new and historical observations of ice sintering and find agreement to some studies at the order of magnitude level. First‐order estimates of neck growth timescales on planetary surfaces show that ice may undergo significant modification over geologic timescales, even in the outer solar system. Densification occurs over much longer timescales, suggesting that some surfaces may develop cohesive, but porous, crusts. Sintering rates are extremely sensitive to temperature and grain size, occurring faster in warmer aggregates of smaller grains. This suggests that the microstructural evolution of ices may vary not only throughout the solar system but also spatially across the surface and in the near surface of a given body. Our experimental observations of complex grain growth and mass redistribution in ice aggregates point to components of the model that may benefit from improvement and areas where additional laboratory studies are needed. Plain Language Summary: Ice sintering is a process that occurs to fresh ice grains deposited onto a planetary surface, which causes them to stick to each other and diffuse together. The contact regions (or necks) between individual grains and the density of the aggregate increases, leading the ice to become stronger and more cohesive over time. This process plays an important role in how ice surfaces evolve, which has implications for predicting their surface characteristics, interpreting spacecraft and telescopic observations, and developing technology to land on and sample these bodies. In this study, we use a numerical model to calculate the rate that sintering occurs in ice grains of varying size and temperature. We compare the predicted sintering rates to experimental observations and calculate estimates of sintering timescales on planetary surfaces. Our results suggest that that ice on planetary surfaces can undergo significant modification over geologic timescales, even in the outer solar system where the cold temperatures result in slow sintering rates. We find that many bodies may develop a cohesive, but porous, surface crusts. Due to the temperature dependence of the process, the evolution of ices is likely to vary significantly throughout the solar system, as well as spatially across a given surface. Key Points: Sintering drives the microstructural evolution of ice through growth of grain‐to‐grain contacts (or necks) and aggregate densityWe use a model to predict ice sintering timescales on planetary surfaces and compare the results to experimental observationsWe find that densification occurs over longer timescales than neck growth, suggesting that surfaces may develop cohesive but porous crusts [ABSTRACT FROM AUTHOR]

Abstract: Bed load sediment transport is an inherently challenging process to measure within a river, which is further complicated by the typically transient nature of the hydrograph. Here we use laboratory experiments to explore how sediment flux under transient—unsteady and intermittent—flow differ from those under steady flow. For a narrow unimodal sediment distribution, we calculated fluid stress and measured sediment flux for a range of hydrograph durations, magnitudes, shapes, and sequences. Within a hydrograph, we find considerable variability in sediment flux for a given stress above the threshold for motion. However, cumulative bed load flux resulting from a flood scales linearly with the integrated excess transport capacity (flow impulse). This scaling indicates that, to first order, flow magnitude, duration, shape, and sequence are only relevant to bed load flux in terms of their contribution to the total flow impulse, in agreement with prior field results. The flood impulse represents a quantitative parameter through which the effects of transient flow on coarse sediment transport may be parsed. [ABSTRACT FROM AUTHOR]

A theoretical debate about whether parasitoids should be time or egg limited now recognizes both as feasible, and interest has turned to determining the circumstances under which each might arise in the field, and their implications for parasitoid behaviour and evolution. Egg loads of parasitoids sampled from the field are predicted to show a negative response to host availability, but empirical support for this relationship is scarce. We measured how a parasitoid's egg load responded to seasonal fluctuations in host population density and recorded the predicted correlation. In early summer, parasitoids were at high risk of time limitation due to low host availability, and in late summer, their offspring were at greater risk of egg limitation due to high host availability. Despite clear seasonal changes in selection pressures on egg load and lifespan, the parasitoid showed no evidence of seasonal variation in its reproductive strategy. We made minor modifications to a previously published model to explore the effects of seasonal variation in host availability on optimal investments in eggs and lifespan and obtained several new results. In particular, under circumstances analogous to some of those observed in our field study, temporal stochasticity in reproductive opportunities can cause investments in eggs to increase, rather than decrease as previously predicted. Our model results helped to explain the parasitoid's lack of a seasonally varying reproductive strategy. Understanding the evolution of parasitoid egg load would benefit from a shift of research emphasis from purely stochastic variation in parasitoid reproductive opportunities to greater consideration of host dynamics. [ABSTRACT FROM AUTHOR]

Understanding the mechanics of bed load at the flood scale is necessary to link hydrology to landscape evolution. Here we report on observations of the transport of coarse sediment tracer particles in a cobblebedded alluvial river and a step-pool bedrock tributary, at the individual flood and multi-annual timescales. Tracer particle data for each survey are composed of measured displacement lengths for individual particles, and the number of tagged particles mobilized. For single floods we find that measured tracer particle displacement lengths are exponentially distributed; the number of mobile particles increases linearly with peak flood Shields stress, indicating partial bed load transport for all observed floods; and modal displacement distances scale linearly with excess shear velocity. These findings provide quantitative field support for a recently proposed modeling framework based on momentum conservation at the grain scale. Tracer displacement is weakly negatively correlated with particle size at the individual flood scale; however cumulative travel distance begins to show a stronger inverse relation to grain size when measured over many transport events. The observed spatial sorting of tracers approaches that of the river bed, and is consistent with size-selective deposition models and laboratory experiments. Tracer displacement data for the bedrock and alluvial channels collapse onto a single curve - despite more than an order of magnitude difference in channel slope - when variations of critical Shields stress and flow resistance between the two are accounted for. Results show how bed load dynamics may be predicted from a record of river stage, providing a direct link between climate and sediment transport. [ABSTRACT FROM AUTHOR]

Background: The mortality and complication rates of many surgical procedures are inversely related to hospital procedure volume. The objective of this study was to determine whether the volumes of primary and revision total hip replacements performed at hospitals and by surgeons are associated with rates of mortality and complications.Methods: We analyzed claims data of Medicare recipients who underwent elective primary total hip replacement (58,521 procedures) or revision total hip replacement (12,956 procedures) between July 1995 and June 1996. We assessed the relationship between surgeon and hospital procedure volume and mortality, dislocation, deep infection, and pulmonary embolus in the first ninety days postoperatively. Analyses were adjusted for age, gender, arthritis diagnosis, comorbid conditions, and income. Analyses of hospital volume were adjusted for surgeon volume, and analyses of surgeon volume were adjusted for hospital volume.Results: Twelve percent of all primary total hip replacements and 49% of all revisions were performed in centers in which ten or fewer of these procedures were carried out in the Medicare population annually. In addition, 52% of the primary total hip replacements and 77% of the revisions were performed by surgeons who carried out ten or fewer of these procedures annually. Patients treated with primary total hip replacement in hospitals in which more than 100 of the procedures were performed per year had a lower risk of death than those treated with primary replacement in hospitals in which ten or fewer procedures were performed per year (mortality rate, 0.7% compared with 1.3%; adjusted odds ratio, 0.58; 95% confidence interval, 0.38, 0.89). Patients treated with primary total hip replacement by surgeons who performed more than fifty of those procedures in Medicare beneficiaries per year had a lower risk of dislocation than those who were treated by surgeons who performed five or fewer of the procedures per year (dislocation rate, 1.5% compared with 4.2%; adjusted odds ratio, 0.49; 95% confidence interval, 0.34, 0.69). Patients who had revision total hip replacement done by surgeons who performed more than ten such procedures per year had a lower rate of mortality than patients who were treated by surgeons who performed three or fewer of the procedures per year (mortality rate, 1.5% compared with 3.1%; adjusted odds ratio, 0.65; 95% confidence interval, 0.44, 0.96).Conclusions: Patients treated at hospitals and by surgeons with higher annual caseloads of primary and revision total hip replacement had lower rates of mortality and of selected complications. These analyses of Medicare claims are limited by a lack of key clinical information such as operative details and preoperative functional status. [ABSTRACT FROM AUTHOR]

Eight South American geographic populations of the parthenogenic, proovigenic, koinobiont parasitoid Microctonus hyperodae Loan (Hymenoptera: Braconidae: Euphorinae) were introduced to New Zealand to assist management of the pasture pest Listronotus bonariensis (Kuschel) (Coleoptera: Curculionidae). Geographic variation in fecundity has been suggested as a reason for the populations' differential successes in establishing in New Zealand. This study investigated whether geographic variation in fecundity was due to corresponding variation in pre-oviposition egg load (other possible sources of fecundity variation include searching efficiency, egg survival and female longevity). Variation in egg load accounted for that in fecundity, but also showed that the variation in fecundity was not as great as it had first appeared. Geographic variation in egg load did not explain the pattern of population establishment observed in New Zealand. Egg load was proportional to parasitoid size and this relationship was stronger in populations originating from west, rather than east, of the Andes. A new method for making parasitoid eggs visible is described. [ABSTRACT FROM AUTHOR]

Background: Previous follow-up studies of patients with Lyme disease suggest that disseminated infection may be associated with long-term neurologic and musculoskeletal morbidity.Objective: To determine clinical and functional outcomes in persons who were treated for Lyme disease in the late 1980s.Design: Population-based, retrospective cohort study.Setting: Nantucket Island, Massachusetts.Participants: 186 persons who had a history of Lyme disease (case-patients) and 167 persons who did not (controls).Measurements: Standardized medical history, physical examination, functional status measure (Medical Outcomes Study 36-item Short Form Health Survey [SF-36]), mood state assessment (Profile of Mood States), neurocognitive tests, and serologic examination.Results: The prevalence of Lyme disease among adults on Nantucket Island was estimated to be 14.3% (95% CI, 9.3% to 19.1%). In multivariate analyses, persons with previous Lyme disease (mean time from infection to study evaluation, 6.0 years) had more joint pain (odds ratio for having joint pain in any joint, 2.1 [CI, 1.2 to 3.5]; P = 0.007), more symptoms of memory impairment (odds ratio for having any memory problem, 1.9 [CI, 1.1 to 3.5]; P = 0.003), and poorer functional status due to pain (odds ratio for 1 point on the SF-36 scale, 1.02 [CI, 1.01 to 1.03]; P < 0.001) than persons without previous Lyme disease. However, on physical examination, case-patients and controls did not differ in musculoskeletal abnormalities, neurologic abnormalities, or neurocognitive performance. Persons with previous Lyme disease who had persistent symptoms after receiving treatment (n = 67) were more likely than those who had completely recovered to have had fever, headache, photosensitivity, or neck stiffness during their acute illness (87% compared with 13%; odds ratio, 2.4 [CI, 1.0 to 5.5]; P = 0.045); however, the performance of the two groups on neurocognitive tests did not significantly differ.Conclusions: Because persons with previous Lyme disease exhibited no sequelae on physical examination and neurocognitive tests a mean of 6.0 years after infection, musculoskeletal and neurocognitive outcomes seem to be favorable. However, long-term impairment of functional status can occur. [ABSTRACT FROM AUTHOR]

Two hundred moles were examined histologically and the degree and type of epidermal change was recorded and correlated with the arrangement, density and type of naevus cells present and with the clinical presentation. Resemblances to the epidermal architecture of seborrhoeic warts were noted in 49 % of the moles studied (this type of change was mainly seen in younger patients). In these there was a predominance of epithelioid cells, mainly in the junctional and upper dermal zones. Thirty-five per cent of moles possessed an epidermis with an overall appearance of being stretched, beneath which was a relatively cleat zone followed by a uniform distribution of predominantly "lymphocytoid" naevus cells and large numbers of naevus cells of the giant type. These were found mainly in the older age groups. A third group (11 %) was characterized by the presence of bulbous epidermal rete ridges and many junctional nests of naevus cells. This group was found mainly in younger age groups and there was often a history of recent change in the mole. It is concluded that the epidermal component of moles might itself be a naevoid disorder or result from the dermal disturbance induced by the mole cells. [ABSTRACT FROM AUTHOR]

The comparison between the size and shape (form) of two structures or the analysis of one object under differing conditions is important in restorative dentistry. Despite rapid advances in digitizing technologies, form comparison is still mainly limited to scalar measurements. The objective of this study was to test the potential use of a newly developed tensorial morphometric difference technique, the macroelement method, in a model restorative system where the processing and materials properties are known: duplication of a denture anchor in stone via polysulfide, addition silicone, and polyether impression materials. Nine machined landmarks were utilized to construct a nine-sided element for macroelement analysis. Macroelement results compared well with the known impression materials properties of polymerization shrinkage and incomplete recovery in terms of: (1) larger die diameter, (2) smaller die (vertically), (3) horizontal direction of maximum expansion, and (4) vertical direction of maximum contraction. Also, macroelement results along boundary lines were equal to the traditional form difference measure of change in length/length of those lines. The macroelement method provided results which are superior to those of traditional methods in that both (1) the magnitude and direction of difference at any point on the structure could be determined, and (2) the graphical representation of the results provides an intuitive appreciation of how and where the forms differ. Therefore, since macroelement results: (1) compare well with known materials properties and traditional measures, and (2) have the above-stated advantages, tensorial techniques such as the macroelement method, used in conjunction with new digitizing technologies, can be used better to describe the kinematics of form difference. With the description of the kinematics provided by the technique, the dynamic cause of the form difference can be ascertained with the investigators' knowledge of materials. The investigators can then suggest changes to be made in materials and/or techniques that would enable the desired size and shape to be obtained. [ABSTRACT FROM AUTHOR]

Background: Cardiac involvement is common in acute Lyme disease, and case reports suggest that cardiac abnormalities might also occur years after the primary infection.Objective: To determine the prevalence of cardiac abnormalities in persons with previously treated Lyme disease.Design: Population-based, retrospective cohort study with controls.Setting: Nantucket Island, Massachusetts.Participants: From among 3703 adult respondents to a total-population (n = 6046) mail survey, 336 (176 case-patients and 160 controls) were randomly selected for clinical evaluation.Measurements: Current cardiac symptoms and major or minor abnormal electrocardiographic features, including heart rate; rhythm; axis; PR, QRS, and QT intervals; QRS structure; atrioventricular blocks; and ST-segment and T-wave changes.Results: Persons with Lyme disease (case-patients, n = 176) (mean duration from disease onset to study evaluation, 5.2 years) and persons without evidence of previous Lyme disease (controls, n = 160) did not differ significantly in their patterns of current cardiac symptoms and electrocardiographic findings, including heart rate (P > 0.2), PR interval (P = 0.15), QRS interval (P > 0.2), QT interval (P > 0.2), axis (P > 0.2), presence of arrhythmias (P > 0.2), first-degree heart block (P = 0.12), bundle-branch block (P > 0.2), and ST-segment abnormalities (P > 0.2). In multivariate analyses that adjusted for age, sex, and previous heart disease, a history of previously treated Lyme disease was not associated with either major (odds ratio, 0.78; P > 0.2) or minor (odds ratio, 1.09; P > 0.2) electrocardiographic abnormalities.Conclusion: Persons with a history of previously treated Lyme disease do not have a higher prevalence of cardiac abnormalities than persons without a history of Lyme disease. [ABSTRACT FROM AUTHOR]

Objective: To ascertain the prevalence of and risk factors for long-term sequelae from acute Lyme disease.Design: Population-based, retrospective cohort study.Setting: A coastal region endemic for Lyme disease.Participants: Patients with a history of Lyme disease who were previously treated with antibiotics were compared with randomly selected controls.Measurements: A standardized physical examination, health status measure (Short Form 36), psychometric test battery, and serologic analysis.Results: Compared with the control group (n = 43), the Lyme group (n = 38; mean duration from disease onset to study evaluation, 6.2 years) had more arthralgias (61% compared with 16%; P < 0.0001); distal paresthesias (16% compared with 2%; P = 0.03); concentration difficulties (16% compared with 2%; P = 0.03); and fatigue (26% compared with 9%; P = 0.04), and they had poorer global health status scores (P = 0.04). The Lyme group also had more abnormal joints (P = 0.02) and more verbal memory deficits (P = 0.01) than did the control group. Overall, 13 patients (34%; 95% CI, 19% to 49%) had long-term sequelae from Lyme disease (arthritis or recurrent arthralgias [n = 6], neurocognitive impairment [n = 4], and neuropathy or myelopathy [n = 3]). Compared with controls, patients who had long-term sequelae had higher IgG antibody titers to the spirochete (P = 0.03) and received treatment later (34.5 months compared with 2.7 months; P < 0.0001).Conclusions: Persons with a history of Lyme disease have more musculoskeletal impairment and a higher prevalence of verbal memory impairment when compared with those without a history of Lyme disease. Our findings suggest that disseminated Lyme disease may be associated with long-term morbidity. [ABSTRACT FROM AUTHOR]

A 50-year-old man with recurrent life-threatening sepsis and a cutaneous condition resembling pyoderma gangrenosum, was found to have a defect of neutrophil phagocytic function. Phagocytosis could be enhanced by corticosteroids, both in vivo in a dose-dependent manner, and in vivo, when it was accompanied by rapid clinical improvement. Studies with steroid hormones and immuno- stimulatory drugs arc described. [ABSTRACT FROM AUTHOR]

Four African female patients are described, who presented with the features of systemic sclerosis. Overlapping features of lupus erythematosus or dermatomyositis were present in three cases but were not prominent. Direct immunofluorescence of uninvolved skin revealed a particulate (or speckled) epidermal nuclear staining, with specificity for IgG. In view of the reported association between this finding and mixed connective tissue disease, these patients were treated with corticosteroids and marked improvement occurred in all cases. The usefulness of this investigation in making the distinction between systemic sclerosis and mixed connective tissue disease and in indicating a potentially effective form of therapy is discussed. [ABSTRACT FROM AUTHOR]

Thirteen patients with cold urticaria were studied to assess the effect of the systemic drug doxantrazole, which has actions resembling disodium cromoglycate, on cold evoked histamine release. The patients, all of whom developed an immediate local whealing response after cooling of the forearm, demonstrated release of histamine into venous blood draining that forearm. Following doxantrazole treatment, significant suppression of histamine release occurred. In some but not all patients this was accompanied by diminution of urtication in response to cooling. A double-blind study was carried out in 3 subjects, all of whom showed diminished cold-stimulated histamine release after doxantrazole. Two of these showed clinical improvement. Doxantrazole had no effect on erythema due to intradermal histamine, but did suppress the erythematous reaction to intradermal injection of compound 48/80. Our results suggest that doxantrazole or related anti-allergic agents might be useful in the treatment of cold urticaria. [ABSTRACT FROM AUTHOR]

This article reports that vasculitis may be an important histological feature of chronic urticaria associated with systemic disease. Researchers found that vasculitis could be induced in the skin of several patients with essential acquired cold urticaria, by repeated cold challenge, as performed during cold-tolerance treatment. In five patients after repeated cold challenge, histological examination of 1 micrometer plastic sections revealed features of early vasculitis principally affecting venules in middle and deep dermal zones and subcutaneous tissue. The endothelial cells were swollen or vacuolated and separated by gaps often containing blood cells.

This article reports on the case study related to transient acantholytic dermatosis. The subject is a male, aged 65 years. In December 1974 he first developed a pruritic rash, predominantly on the upper trunk with the axillae, neck, periumbihcal area, upper arms and thighs also involved. At first he had many small blisters, but these no longer occur, although the pruritic rash has persisted, in spite of the use of antihistamines, topical steroids and dapsone. On examination. Small pin-head vesicles were present originally on the upper trunk, but more recently only excoriated papular lesions have been observed.

The article reports the inhibitory influence of the cromone-like drug doxantrazole on cold-stimulated histamine release and urtication in patients with cold urticaria. Six patients with cold urticaria who had immediate wealing responses to skin cooling were studied. The arm was cooled by water immersion at a predetermined temperature before and after systemic administration of doxantrazole. Histamine in venous blood draining the cooled forearm skin was measured by bio- assay using a cascade superfusion method as previously described. That doxantrazole reduces evoked histamine release from skin mast cells was further suggested by reduction in the flare reaction to intradermal injection of the histamine liberator compound 48/80 in patients receiving doxantrazole.

Presents an abstract of the article "Are Moles Just Naevus Cells?," by C. B. Bentley-Phillips and R. Marks.

Laboratory host specificity of 2 biological control agents, already introduced in New Zealand, was compared with actual field parasitism.The parasitoids were Microctonus aethiopoides Loan and Microctonus hyperodae Loan, braconids imported to control the curculionid forage pests Sitona discoideus Gyllenhal and Listronotus bonariensis (Kuschel), respectively. The nontarget weevil species tested included native,introduced, and beneficial species. M. aethiopoides oviposited in 11of the 12 species to which it was exposed and successfully parasitized 9 species. M. hyperodae oviposited in 5 of the 11 species to whichit was exposed and developed successfully in 4 species. Higher percentage parasitism was recorded with M. aethiopoides than with M. hyperodae. Field collections of weevils from Otago, Canterbury, and Waikato indicated that 10 New Zealand natives and 3 other nontarget species, including the weed biological control agent Rhinocyllus conicus (Froehlich), were parasitized by M. aethiopoides. M. hyperodae has been found parasitizing 1 native species, as well as Sitona lepidus Gyllenhal, which was accidentally introduced to New Zealand recently. In nontarget species, parasitism levels in the field of >70% have been recorded for M. aethiopoides and <5% for M. hyperodae. The results of this study suggest that laboratory host range testing is indicative of nontarget parasitism in the field. [ABSTRACT FROM AUTHOR]

Although an uncommon entity, familial glomangiomatosis is often a source of significant discomfort to affected patients and impacts quality of life. Patients develop numerous painful vascular lesions, beginning in childhood. Because management strategies for this entity are sparsely reported in the literature, additional study is needed to establish best practice. We report positive results with the use of Nd:YAG laser in treating symptomatic lesions of familial glomuvenous malformation.

Objective: Supplementary questionnaires provide additional information from subgroups, but may have an attritional effect on response rates. We examined the effects of different instruction methods on response rates to a two-part questionnaire., Methods: The ACT Kindergarten Health Survey comprises a health questionnaire for all school-entry children. A supplementary questionnaire targets children with respiratory symptoms. We cluster-randomised 109 schools in the ACT (4,494 children) to two instruction groups. Group 1 (instruction burden) had instructions to complete the supplementary questionnaire if certain questions in the primary questionnaire were answered. Group 2 (response burden) had instructions to complete both questionnaires irrespective of answers to the primary questionnaire., Results: Instructing all respondents to complete both questionnaires regardless of eligibility resulted in a statistically significantly lower primary questionnaire response rate (82% vs. 87%), but a statistically significantly higher response rate to the supplementary questionnaire (99% vs. 91%). The net effect was a small overall gain (82% vs. 79%) for the response burden group., Conclusion: Increasing the response burden had a minor impact on response rate to the primary questionnaire, but increased the response rate for most items to the supplementary questionnaire., Implications: Large surveys may be broken into primary and supplementary questionnaires, if strategies to maximise response rates are used. Questionnaires may need to be modified to take into account the likely attrition on response to either questionnaire resulting from instruction and response burdens.