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Importance: The use of 3-dimensional (3D) endoscopy has been described in the pediatric airway and has been shown to improve visualization of complex airway anatomy. Laryngomalacia is one of the most common airway disorders evaluated in pediatric otolaryngology offices. Whether 3D visualization is superior to standard endoscopy as a means for assessment and surgical management of complex airway anatomy is unclear., Objective: To describe a pilot case series using 3D endoscopy to facilitate supraglottoplasty and to assess surgical outcomes., Design, Setting, and Participants: A prospective case series was conducted of 11 children undergoing supraglottoplasty from July 1, 2010, to June 31, 2014, at a tertiary care pediatric hospital. Infants and children with symptomatic laryngomalacia were eligible for the study. Follow-up was completed on December 31, 2014, and data were assessed from February 1 to 15, 2015., Interventions: Supraglottoplasty performed using 3D endoscopy., Main Outcomes and Measures: The outcome data collected included length of hospital stay and frequency of complications (ie, aspiration, granuloma formation, supraglottic narrowing, revision surgery, tracheostomy, and gastrostomy)., Results: Eleven children were treated for laryngomalacia with supraglottoplasty (6 boys and 5 girls; mean [SD] age, 29 [85] months). Four of these children (36%) also had grade I subglottic stenosis. The 3D endoscope was judged by all participating senior surgeons to improve visualization of the supraglottic anatomy and to permit more precise tissue removal. No complications occurred after the surgery. Hospital stay was found to be an unreliable indicator owing to multiple comorbidities in many children. Worsening of aspiration occurred in 1 child (9%) who subsequently required gastrostomy tube placement. This child demonstrated progressive neurologic impairment and had severe hypotonia and developmental delay. Another child with subglottic stenosis and subglottic cysts required a tracheostomy owing to severe rhinovirus tracheitis. The remaining 9 children (82%) had good outcomes, with a mean follow-up of 14.7 (range, 12-24) months., Conclusions and Relevance: The anatomy of the supraglottis in laryngomalacia is better visualized using 3D techniques. Use of 3D endoscopy may allow for more precise tissue removal. The outcomes and complication rates are similar to those of standard 2D techniques. This study provides a platform to begin comparative analysis between 3D and standard 2D techniques.

ABSTRACT In this article, insights into the lived experience of homeless women arising from a PhD study on the specialist role of the SCPHN in homelessness are presented. A key narrative text of a rough sleeping pregnant woman is included. The reflexive narrative study, used an eclectic, philosophical framework which included reflective practice/guidance, narrative inquiry, and storytelling methodologies. Story texts uniquely illuminated complex knowledge about homelessness and homeless health care. Homeless women were found to be a heterogeneous group which included former health professionals. The women's stories were often shocking; they were frequently contextualised against a background of service exclusion, including GP services, learning disability services, mental health services, housing services and social services. The role of the specialist nurse (SCPHN) in engagement with homeless people is illuminated. A therapeutic model of 'Effective Engagement with Homeless People and Homeless Families' is presented to guide health professionals in holistic care. The author invites the reader to dialogue within their teams on how homeless people are included or excluded from SCPHN services. In this way, the term 'audiencing' rather than transferability of findings is used in a continuing dialogue with the reader to improve the health and wellbeing of homeless women.

Reflective practice was used as a process of self-inquiry and transformation in a PhD study of my specialist role in single and family homelessness. New to homelessness when I embarked on the study, there was little to guide my nursing practice and, notably, there was insufficient research evidence to demonstrate the effectiveness of specialist practice with homeless people. Through my reflexive narrative study, that research gap was addressed. The aim of the narrative was to inform the reader of the reflexive journey and my transformation as a specialist practitioner in homeless health care, and to invite readers to reflect on their own perceptions of homelessness along with the health needs of homeless people. Study findings illuminated the key ethical role that mainstream health professionals, including specialist community public health nurses (SCPHNs), have towards effective engagement to reduce suffering and prevent homeless people and families falling through the net of care. As my research progressed I metaphorically understood the specialist practitioner role as a clinical and strategic 'net-weaver' in a net of care between homeless people, multi-agency partnerships, community and acute health services, and in education.

Emphysematous pyelonephritis (EPN) is a severe necrotizing infection of the renal parenchyma. The clinical course of EPN can be severe and life-threatening if not recognized and treated promptly. Most of the information has been from case reports, a few large series have also been reported. Using an evidence-based approach, this review describes the pathogenesis, classification, complications, and management of EPN. Emphysematous pyelonephritis (EPN) is an acute severe necrotizing infection of the renal parenchyma and its surrounding tissues that results in the presence of gas in the renal parenchyma, collecting system, or perinephric tissue. The cause for mortality in EPN is primarily due to septic complications. Up to 95% of the cases with EPN have underlying uncontrolled diabetes mellitus. The risk of developing EPN secondary to a urinary tract obstruction is about 25-40%. There are three classifications of EPN based on radiological findings. Acute renal failure, microscopic or macroscopic haematuria, severe proteinuria are other positive findings in EPN. Escherichia coli is the most common causative pathogen with the organism isolated on urine or pus cultures in nearly 70% of the reported cases. A plain radiograph shows an abnormal gas shadow in the renal bed raising the suspicion whereas an ultrasound scan or computed tomography (CT) will confirm the presence of intra-renal gas thus supporting the diagnosis of EPN. Gas may extend beyond the site of inflammation to the sub capsular, perinephric and pararenal spaces. In some cases, gas was found to be extending into the scrotal sac and spermatic cord. Subsequent case studies have shown patients being successfully treated with PCD when used in addition to medical management, with significant reduction in the morality rates. PCD should be performed on patients who have localized areas of gas and functioning renal tissue is present. The treatment strategies include MM alone, PCD plus MM, MM plus emergency nephrectomy, and PCD plus MM plus emergency nephrectomy. In small proportion of patients managed with MM and PCD, subsequent nephrectomy will be required and in these patients the reported mortality is 6.6% Nephrectomy in patients with EPN can be simple, radical or laparoscopic., (© 2010 THE AUTHORS. BJU INTERNATIONAL © 2010 BJU INTERNATIONAL.)

Ferrets have increased in popularity as pets, and a growing number are seen in companion animal practice. Domestic ferrets are commonly used as animal models for research of human oral conditions. The present study evaluated the prevalence of oral pathology in rescued ferrets which - to the authors' knowledge - has not yet been described in the scientific literature. Conscious oral examination was performed on 63 ferrets, of which 49 underwent general anesthesia for further examination. The most common clinical findings included malocclusion of mandibular second incisor teeth (95.2%); extrusion of canine teeth (93.7%); and abrasion and attrition of teeth (76.2%). Tooth fractures were exclusively associated with canine teeth and found in 31.7% of ferrets. Pulp exposure was confirmed in 60.0% of fractured teeth. The normal gingival sulcus depth measured < 0.5-mm in 87.8% of anesthetized ferrets. Clinical evidence of periodontal disease was present in 65.3% of anesthetized ferrets (gingivitis or probing depths > 0.5-mm), however advanced periodontal disease (i.e. periodontal pockets > 2-mm or stage 3 furcation exposure) was not found upon clinical examination. There was no evidence of tooth resorption, dental caries, stomatitis, or oral tumors in the examined group of ferrets.

Background: Despite national and international policies to develop social capital in disaster-affected communities, empiric evidence on the association between social capital and disaster mental health is limited and ambiguous., Objective: The study explores the relationship between social capital and disaster mental health outcomes (PTSD, anxiety, and depression) in combination with individual factors (appraisal, coping behavior, and social support)., Design: This is a community-based cross-sectional study in a flood-affected town in northern England. The study is part of the MICRODIS multi-country research project that examines the impact of natural disasters. It included 232 flood-affected respondents., Results: The findings showed that a considerable part of the association between cognitive and structural social capital and mental health is exerted through individual appraisal processes (i.e. property loss, primary and secondary appraisal), social support, and coping behavior. These individual factors were contingent on social capital. After the inclusion of individual characteristics, cognitive social capital was negatively related to lower mental health problems and structural social capital was positively associated to experiencing anxiety but not to PTSD or depression. Depression and anxiety showed a different pattern of association with both components of social capital., Conclusions: Individual oriented stress reducing interventions that use appraisal processes, social support, and coping as starting points could be more effective by taking into account the subjective experience of the social context in terms of trust and feelings of mutual support and reciprocity in a community. Findings indicate that affected people may especially benefit from a combination of individual stress reducing interventions and psychosocial interventions that foster cognitive social capital.

An adult, presumed intact female Umbrella Cockatoo (Cacatua alba), presented with acute hemorrhage from an intraocular mass that perforated through the right cornea. Computed tomography scanning revealed a large soft tissue mass in the right orbit, invading and displacing the globe laterally, and destroying the scleral ossicles. There was no evidence of bony changes of the orbit or extension of the mass into the optic nerve or brain. Exenteration and mass removal were performed, and osteosarcoma was diagnosed via histopathology. Radiotherapy was delivered with an orthovoltage unit to a total dose of 68 Gray delivered in 17 fractions over 6 weeks. The bird recovered well from treatment, but died 2 months after the last radiation session with neurological signs. Necropsy was not performed. To our knowledge, this is the first case of an intraocular osteosarcoma reported in a bird, and the first case of attempted treatment of osteosarcoma in a bird by a combination of surgery and radiation therapy.

The establishment of reference intervals for hematologic and blood chemistry values in a given species is essential for subsequent diagnosis of disease at rehabilitation facilities and in captive breeding programs. In this study, blood samples were obtained from nestlings (18 males and 22 females) of a natural-vegetation breeding population of Montagu's harrier (Circus pygargus) in eastern Spain in order to establish reference intervals for blood values. This is the first study documenting hematologic and biochemical reference intervals for free-living Montagu's harriers. The studied population may reflect typical blood values for the species, since it is a free-living population that seems not to be constrained by food availability, as it is the population of Montagu's harriers with the highest productivity within Europe. Differences related to sex, year, clutch size, brood size, and number of fledglings were analyzed. Packed cell volume and hemoglobin were significantly lower from nests with five chicks compared to values from nests with fewer chicks, indicating that the cost of rearing more than four chicks in this species may be excessive. Total protein, calcium (Ca), and phosphorus (P) were significantly lower in the year with lowest mean rainfall, which correlates with the worst breeding success rate since the population has been monitored. No gender differences were found; this is likely a result of the prepubertal age of the animals sampled.

By learning lessons from weed science we have adopted three approaches to make plants more effective in phytoremediation: (1) The application of functional genomics to identify key components involved in the detoxification of, or tolerance to, xenobiotics for use in subsequent genetic engineering/breeding programmes. (2) The rational metabolic engineering of plants through the use of forced evolution of protective enzymes, or alternatively transgenesis of detoxification pathways. (3) The use of chemical treatments which protect plants from herbicide injury. In this paper we examine the regulation of the xenome by herbicide safeners, which are chemicals widely used in crop protection due to their ability to enhance herbicide selectivity in cereals. We demonstrate that these chemicals act to enhance two major groups of phase 2 detoxification enzymes, notably the glutathione transferases and glucosyltransferases, in both cereals and the model plant Arabidopsis thaliana, with the safeners acting in a chemical- and species-specific manner. Our results demonstrate that by choosing the right combination of safener and plant it should be possible to enhance the tolerance of diverse plants to a wide range of xenobiotics including pollutants.

Intra-abdominal (as opposed to extremity or limb and limb-girdle) soft tissue sarcomas (STS) are rare and account for less than 1% of all diagnosed neoplasms. These tumours are usually associated with a poor prognosis and are often locally invasive and metastatic at the time of presentation. Retroperitoneal sarcomas with synchronous or metachronous different histological types are rare and intra-duodenal sarcomas extremely unusual. A case of a giant retroperitoneal STS weighing approximately 15 kg consisting of two histologically different types is presented. Intra-duodenal involvement with sarcoma was found intra-operatively. We discuss the management of this condition in the context of an illustrative case in our recent experience.

Aim: Ten percent of soft tissue sarcomas (STS) arise in the retroperitoneal tissues. The prognosis for patients with retroperitoneal sarcoma is poor with a 5-year survival rate between 12% and 70%. Stage at presentation, high histological grade, unresectable primary tumour and incomplete resection are associated with a less favourable outcome., Methods: Complete follow-up data were available on 22 patients who underwent surgery for retroperitoneal STS in our institution between 1990 and 2000. Patient, tumour and treatment variables were analysed including use of adjuvant therapy and survival status., Results: Eighteen patients underwent surgery for primary disease, four patients were treated for recurrent disease or metastases. Ten patients presented with pain, seven with an abdominal mass, other presentation included weight loss and haematuria. Thirteen patients presented with tumours larger than 10 cm. The tumours were seven liposarcomas, six leiomyosarcomas, three malignant fibrous histiocytomas, two rhabdomyosarcomas, two malignant schwannomas and two undifferentiated sarcomas. Six primary tumours were completely excised, five patients received radiotherapy and five received chemotherapy. Local recurrence rate was 45% and recurrence-free interval for 10 patients with recurrence was 11 months. Five patients received radiotherapy and five received chemotherapy. The median survival for patients with primary tumours was 36 months, and 5-year survival was 44%. Adjuvant therapy was not associated with higher survival rates., Conclusion: This study re-emphasizes the poor outcome of patients with retroperitoneal STS. Adjuvant radiotherapy and chemotherapy do not appear to be any proven benefit and the single most important prognostic factor is aggressive successful en bloc resection of the primary tumour. Our resection rate and 5-year survival rates are comparable with previous reported UK series although lower than large reports from North American centres. This might partly be explained by difficulty in data collection in a retrospective analysis, but may reflect inadequate subspecialization in UK centres., (Copyright Harcourt Publishers Limited.)

Heat shock proteins (hsps) occupy a central role in the regulation of intracellular homeostasis, and differential expression of individual hsps occurs in a broad range of neoplastic processes. This study was performed to test the hypothesis that the particular patterns by which individual hsps become specifically modulated in human prostate cancers are correlated with behavioral phenotype and hence may be of value in determining the most appropriate clinical management of individual patients. Monoclonal antibodies specific for each hsp protein were used to assess expression of hsp27, hsp60, and hsp70 in formalin-fixed, paraffin wax-embedded, archival tissue specimens of early prostatic adenocarcinomas (pT1-2N0M0) removed at radical prostatectomy (n = 25) and in advanced cancers (n = 95) identified at transurethral resection of prostate (TURP). These findings were compared with similar data from control prostates (n = 10) removed at primary cystectomy for urinary bladder neoplasia not involving the prostate and also at TURP for benign prostatic hyperplasia (n = 50). Western blotting of whole cell lysates derived from established human prostatic epithelial cell lines PNT2, LNCaP, DU145, and PC3 was compared with expression of hsps by the primary human tissues. This study found that early in situ neoplastic transformation of normal prostatic epithelium was consistently associated with loss of hsp27 expression and that the level of hsp27 expression by individual prostate cancers was correlated with their Gleason grade. In advanced cancers, hsp27 expression was invariably associated with poor clinical outcome (P = 0.0001). Data from cell lines supported the primary tissue findings, with elevated hsp27 expression only in aggressive malignant cell lines and androgen-insensitive cell lines. Expression of hsp60 was significantly increased in both early and advanced prostate cancer when compared with nonneoplastic prostatic epithelium (P < 0.0001), as well as in malignant prostate cancer cell lines. Expression of hsp70 was unaltered in early prostate cancers when compared with nonneoplastic prostatic epithelium but showed a diminished expression in morphologically advanced cancers (P = 0.0029). No consistent correlation was found between levels of hsp60 or hsp70 expression and phenotypic behavior of individual primary prostatic cancers. Thus, patterns of hsp expression have been confirmed to be specifically and consistently modulated in both early and advanced human prostate cancers. Whereas absence of hsp27 is a reliable objective marker of early prostatic neoplasia, reexpression of this protein by an individual invasive prostatic carcinoma invariably heralds poor clinical prognosis. Because this protein has been shown to alter the balance between proliferation and apoptosis, understanding the mechanism(s) by which individual hsps regulate intracellular homeostasis may assist in explaining some key processes that occur during evolution of human prostate cancers. We suggest that hsp27 expression provides novel diagnostic and prognostic information on individual patient survival which, if obtained at the time of primary diagnosis, would assist in determining tumor-specific management strategies. Development of techniques to therapeutically modulate hsp27 expression raises the possibility of novel targeted approaches to regulate this homeostatic mechanism, thus allowing better control over tumor cell proliferation and hence patient survival.

The author discussed various advanced roles for the perioperative RN; commitment and passion for the OR professional; the need for education, education, education; and how to plan your career.

Acclimation to elevated CO 2 was investigated in Parmelia caperata originating from the vicinity of a natural CO 2 spring, where the average daytime CO 2 concentration was 729 ± 39 μmol mol -1 dry air. Thalli showed no evidence of a down-regulation in photosynthetic capacity following long-term exposure to CO 2 enrichment in the field; carboxylation efficiency, total Ribulose bisphosphate carboxylase/oxygenase (Rubisco) content, apparent quantum yield of CO 2 assimilation, and the light-saturated rate of CO 2 assimilation (measured under ambient and saturating CO 2 concentrations) were similar in thalli from the naturally CO 2 enriched site and an adjacent control site where the average long-term CO 2 concentration was about 355 μmol mol -1 . Thalli from both CO 2 environments exhibited low CO 2 compensation points and early saturation of CO 2 uptake kinetics in response to increasing external CO 2 concentrations, suggesting the presence of an active carbon-concentrating mechanism. Consistent with the lack of significant effects on photosynthetic metabolism, no changes were found in the nitrogen content of thalli following prolonged exposure to elevated CO 2 . Detailed intrathalline analysis revealed a decreased investment of nitrogen in Rubisco in the pyrenoid of algae located in the elongation zone of thalli originating from elevated CO 2 , an effect associated with a reduction in the percentage of the cell volume occupied by lipid bodies and starch grains. Although these differences did not affect the photosynthetic capacity of thalli, there was evidence of enhanced limitations to CO 2 assimilation in lichens originating from the CO 2 -enriched site. The light-saturated rate of CO 2 assimilation measured at the average growth CO 2 concentration was found to be significantly lower in thalli originating from a CO 2 -enriched atmosphere compared with that of thalli originating and measured at ambient CO 2 . At lower photosynthetic photon flux densities, the light compensation point of net CO 2 assimilation was significantly higher in thalli originating from elevated CO 2 , and this effect was associated with higher usnic acid content.

Gender awareness and sensitivity in disaster research and management remains uncommon and tends to focus on the developing rather than the developed world. This paper uses a feminist oral geography to present some findings about women's experiences in two floods in Scotland. It is conceptualised around public and private (masculinised and feminised) space, problematising the private domain and presenting it, in the feminist research tradition, as a legitimate object of research. It shows the ordinary and everyday to be more opaque and complex than usually imagined and makes recommendations for their recognition and incorporation into disaster management. While there is a specific focus on the private domain of the home, this is not intended to reinforce gender stereotypes but simply to recognise the reality of many of the women interviewed. It concludes that disaster research generally has yet to advance much beyond the earliest stages of feminist studies which merely sought to make women visible in society.

The aim of this study was to characterise growth and photosynthetic capacity in plants adapted to long-term contrasting atmospheric CO 2 concentrations (C a ). Seeds of Agrostis canina L. ssp. monteluccii were collected from a natural CO 2 transect in central-western Italy and plants grown in controlled environment chambers at both ambient and elevated CO 2 (350 and 700 μmol mol -1 ) in nutrient-rich soil. Seasonal mean C a at the source of the plant material ranged from 610 to 451 μmol CO 2 mol -1 , derived from C 4 leaf stable carbon isotope discrimination (δ 13 C). Under chamber conditions, CO 2 enrichment stimulated the growth of all populations. However, plants originating from elevated C a exhibited higher initial relative growth rates (RGRs) irrespective of chamber CO 2 concentrations and a positive relationship was found between RGR and C a at the seed source. Seed weight was positively correlated with C a , but differences in seed weight were found to explain no more than 34% of the variation in RGRs at elevated CO 2 . Longer-term experiments (over 98 days) on two populations originating from the extremes of the transect (451 and 610 μmol CO 2 mol -1 ) indicated that differences in growth between populations were maintained when plants were grown at both 350 and 700 μmol CO 2 mol -1 . Analysis of leaf material revealed an increase in the cell wall fraction (CWF) in plants grown at elevated CO 2 , with plants originating from high C a exhibiting constitutively lower levels but a variable response in terms of the degree of lignification. In vivo gas exchange measurements revealed no significant differences in light and CO 2 saturated rates of photosynthesis and carboxylation efficiency between populations or with CO 2 treatment. Moreover, SDS-PAGE/ LISA quantification of leaf ribulose bisphosphate carboxylase/oxygenase (Rubisco) showed no difference in Rubisco content between populations or CO 2 treatments. These findings suggest that long-term adaptation to growth at elevated CO 2 may be associated with a potential for increased growth, but this does not appear to be linked with differences in the intrinsic capacity for photosynthesis.

Objective: To determine the effectiveness of prostatectomy in reducing symptom severity and bother and in improving disease-specific and general quality of life., Patients and Methods: A prospective, cohort study was performed in National Health Service and private hospitals in the Northern, Wessex, Mersey, and South-West Thames Health Regions which comprised 5276 men undergoing prostatectomy recruited by 101 of the 106 (96%) surgeons (specialist and non-specialist) performing prostatectomy during a 6-month period. Patients were assessed using the American Urological Association (AUA) Symptom Index Score, the AUA symptom bother score, disease-specific and generic quality-of-life scores, the occurrence of adverse events (urinary incontinence, erectile impotence and retrograde ejaculation) and three global (general) questions on the results of their treatment. The outcome was assessed 3 months after surgery., Results: Prostatectomy was effective in reducing both symptoms (initial mean score 20.1 reduced to 7.4, P < 0.001) and symptom bother (initial mean score 14.4 reduced to 4.3, P < 0.001). Not all men experienced a good reduction in symptoms; 121 (3.9%) were worse, 301 (9.6%) were the same, and 721 (23%) experienced only slight improvement. The type of operation, grade of principal operator and use of pre-operative investigations were not associated with the extent of symptomatic improvement. Changes in symptom severity were highly correlated with changes in bothersomeness++ and disease-specific quality of life but not with generic quality of life. A third of men who were continent before surgery reported some incontinence 3 months later, although only 6% found it a problem. Two-thirds of men experienced retrograde ejaculation and 31% experienced some erectile impotence following surgery., Conclusions: Prostatectomy is effective in reducing symptoms in most men. Men who experience a substantial reduction in symptoms were more likely to report a favourable outcome. The study confirmed that approximately one-third of men reported an unfavourable result 3 months after their operation.

There is increasing interest in the acquisition and measurement of physical fitness in general populations (Bassey and Fentem 1981). Measuring fitness can be uncomfortable and exhausting for subjects and expensive and time-consuming for experimenters (Andersen et al. 1971). Various authors have described and/or evaluated methods for the prediction of VO2 max (Astrand and Rhyming 1954, Davies 1968, Fitchett 1985, Harrison et al. 1980, Jette 1979, Jette et al. 1982, Shephard 1975, Shephard et al. 1979). A valid, safe, socially-acceptable alternative for such measurements applicable to a population would be of benefit. Asking subjects how they perceive their own physical fitness might be such an alternative. The validity and reliability of the data contained from such a questionnaire could be tested against conventional measures of physical fitness. A study which incorporated questionnaire surveys as one method of determining physical fitness in a large population was undertaken on Fire Service personnel in England, Scotland, and Wales (Ellam et al. 1985); a subsample of the population were questioned in the same way but in addition their fitness was assessed by physiological measurements. This paper describes the characteristics of the physical fitness of an average fireman as revealed by responses to questionnaires and how firemen felt their fitness was related to their working duties; it further examines these in relation to objective measurements.

On-line instantaneous carbon isotope discrimination was measured in conjunction with net uptake of CO 2 in leaves of exposed and shaded plants of the C 3 -CAM intermediate Clusia minor growing under natural conditions in Trinidad. At the end of the rainy season (late January-early February, 1992) C 3 photosynthesis predominated although exposed leaves recaptured a small proportion of respiratory CO 2 at night for the synthesis of malic acid. Citric acid was the major organic acid accumulated by exposed leaves at this time with a citric: malic acid ratio of 11:1. Values of instantaneous discrimination (Δ) in exposed leaves during the wet season rose from 17.1‰ shortly after dawn to 22.7‰ around mid-day just before stomata closed, suggesting that most CO 2 was fixed by Rubisco at this time. During the late afternoon, instantaneous Δ declined from 22.2‰ to 17‰, probably reflecting the limited contribution from PEPc activity and an increase in diffusional resistance to CO 2 in exposed leaves. Shaded leaves showed no CAM activity and CO 2 uptake proceeded throughout the day in the wet season. The decrease in instantaneous Δ from 27‰ in the morning to 19.2‰ in the late afternoon was therefore entirely due to diffusional limitation. Leaves sampled in the dry season (mid-March, 1992) had by now induced full CAM activity with both malic and citric acids accumulated overnight and stomata closed for 4-5 h over the middle of the day. Values of instantaneous Δ measured over the first 3 h after dawn (6.4-9.1‰) indicated that C 4 carboxylation dominated CO 2 uptake for most of the morning when rates of photosynthesis were maximal, implying that under natural conditions, the down regulation of PEPc in phase II occurs much more slowly than laboratory-based studies have suggested. The contribution from C 3 carboxylation to CO 2 uptake during phase II was most marked in leaves which accumulated lower quantities of organic acids overnight. In exposed leaves, measurements of instantaneous Δ during the late afternoon illustrated the transition from C 3 to C 4 carboxylation with stomata remaining open during the transition from dusk into the dark period. Uptake of CO 2 by shaded leaves during the late afternoon however appeared to be predominantly limited by decreased stomatal conductance. The short-term measurements of instantaneous Δ were subsequently integrated over 24 h in order to predict the leaf carbon isotope ratios (δ p ) and to compare this with the δ p measured for leaf organic material. Whilst there was close agreement between predicted and measured δ p for plants sampled in the wet season, during the dry season the predicted carbon isotope ratios were 5-9‰ higher than the measured isotope ratios. During the annual cycle of leaf growth most carbon was fixed via the C 3 pathway although CAM clearly plays an important role in maintaining photochemical integrity in the dry season.

Four main groups are considered in relation to the risk from flooding: the engineers involved in the design of flood alleviation schemes, emergency planners, the public, including both the population at risk from flooding and the rest of the population who will bear all or most of the cost of flood alleviation schemes and the researchers, such as geographers and economists concerned with flood hazards and scheme appraisal. It is argued that these different groups vary significantly in their selection and definition of risks from flooding as a focus of concern and that their definition of risk influences their expectations about future events and the appropriate response to those events. But the different groups share two tendencies: the expectation that the future will be a replication of the past; and the neglect of "uncertain uncertainties" in favour of known uncertainties of risk.

Scanning confocal microscopes offer improved rejection of out-of-focus noise and greater resolution than conventional imaging. In such a microscope, the imaging and condenser lenses are identical and confocal. These two lenses are replaced by a single lens when epi-illumination is used, making confocal imaging particularly applicable to incident light microscopy. We describe the results we have obtained with a confocal system in which scanning is performed by moving the light beam, rather than the stage. This system is considerably faster than the scanned stage microscope and is easy to use. We have found that confocal imaging gives greatly enhanced images of biological structures viewed with epifluorescence. The improvements are such that it is possible to optically section thick specimens with little degradation in the image quality of interior sections.