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Large‐scale floodplains are important features of the African continent. Regular inundation provides the means to support large populations but can also present problems such as access to health facilities and water body formation that sustain malaria vectors. Modeling of these floodplains is therefore important, but complex. In this research, we develop, calibrate, and validate a hydrodynamic model of the Barotse Floodplain, of the Upper Zambezi, Zambia. The floodplain has seen recent infrastructure developments including the restoration of the canal network and construction of a cross floodplain causeway. In order to create a robust model, a multiobjective calibration uses a time slice approach based on available Landsat satellite image overpasses. An emulator‐based sensitivity analysis indicates the significance of hydrological processes in the model. Model evaluation is undertaken for two events in the gauge record (2009 and 2018), of similar magnitude that occur before and after modifications to the floodplain. Results indicate a complex impact of infrastructure development on the hydrodynamics of the floodplain, with a higher peak flow, but with a redistribution of water throughout the floodplain. Deeper flooding is observed in some areas while others experience lower water levels. The sensitivity results also reflect a change in processes, where floodplain flows dominate the 2009 event, whilst channel process dominate the 2018 event. Overall, we show that relatively modest modifications to the floodplain have impacted flood water levels, which in turn will influence access route availability and alter malaria transmission rates. Key Points: Large floodplains are hydrodynamically sensitive to relatively modest changesModifications of the floodplain have influenced the timing and distribution of floodwatersA robust modeling approach is created through a multiobjective function and time slice calibration approach [ABSTRACT FROM AUTHOR]

Summary: Successful placement of an i.v. catheter in horses is a core competency required by the AVMA COE accreditation policy (section 7.11, #2,#3,#5). Therefore, we determined whether the use of a novel intravenous (i.v.) catheter placement training tool would improve confidence, time to successful placement and accuracy with which third‐ and fourth‐year veterinary students acquire competence regarding this skill in adult horses. Students lacking earlier experience with i.v. catheter placement in horses were randomly assigned to either Group 1 (n = 15) or 2 (n = 10). Students with prior experience with the technique were assigned to Group 3 (n = 14). Group 1 students were instructed on i.v. catheter placement using the model and then assessed using a live horse. Group 2 students were instructed on i.v. catheter placement using a live horse and then assessed using a live horse. Group 3 students were assessed using a live horse. Assessments included number of placement attempts, number of redirects and time needed to achieve correct intraluminal placement. Student perceptions regarding the use of this model for the purpose of learning i.v. catheter placement in horses were evaluated using a questionnaire. Results of this study demonstrated that students receiving initial instruction with the model achieved better scores in terms of both time to accomplish the task and accuracy for catheter placement in a live horse when compared with students that received their first instruction on a live horse. The use of this i.v. catheter placement training tool therefore served to lessen the cost of training and to minimise animal discomfort during this component of veterinary student training. [ABSTRACT FROM AUTHOR]

Background: Energy drinks (ED) are popular among young people despite evidence of associated health risks. Research into the prevalence and pattern of ED intake among young people is sparse. The present study investigates the prevalence and pattern of ED intake among a large sample of adolescents, including how many consume them, how often, for what reasons and in what contexts. Methods: In 2018, all students in grades 7–12 attending 25 randomly selected Western Australian schools were invited to complete an online self‐report survey about EDs. Results: Of the 3688 respondents, 51.2% reported consuming an ED. Of these 'ever consumers', 23.4% drank them monthly, 19.2% weekly and 2% every day. The average age of first intake was 10.7 years. One‐fifth (19.7%) of 'ever consumers' reported consuming more than two EDs in 1 day. Reasons for ED use included taste, to boost energy levels, sport performance and studying. Conclusions: The findings add to limited international evidence about adolescent ED use and provide valuable information to help ensure interventions to reduce intake address the underlying reasons and contexts of ED consumption. [ABSTRACT FROM AUTHOR]

Difficulty in tracheal intubation in paediatric intensive care patients is associated with increased morbidity and mortality. Delays to intubation and interruption to oxygenation and ventilation are poorly tolerated. We developed a safe and atraumatic tracheal intubation technique. A floppy-tipped guidewire and airway exchange catheter were placed to a pre-determined length under bronchoscopic guidance while oxygenation and ventilation was maintained via a supraglottic airway device (SAD). We performed a retrospective review of this technique on patients who were either known to have or who had an unexpected difficultly in intubation. We describe the safety and experience of this in a broad range of critically ill children. Thirteen patients, median (IQR [range]) (9.0 (5.0-10.0 [4.0-12.0]) kg and 15.4 (12.1-23.2 [3.3-49.7]) months) underwent emergency tracheal intubation using this technique, after unsuccessful attempts at intubation using standard laryngoscopy blades. All intubations were successful at the first attempt using this technique and no airway trauma or significant clinical deteriorations were recorded. [ABSTRACT FROM AUTHOR]

Leptosphaeria maculans is the causal agent of blackleg, a serious disease on canola/rapeseed in western Canada, Australia and Europe. Genetic resistance and extended crop rotation provided effective disease control in western Canada for years but the emergence of new pathogen races has reduced the effectiveness of current management strategies. The objective of this study was to analyse L. maculans isolates derived from canola stubble in commercial fields collected in 2010 and 2011 across western Canada for the presence and frequency of avirulence ( Avr) genes. A total of 674 isolates were examined for the presence of Avr alleles AvrLm1, AvrLm2, AvrLm3, AvrLm4, AvrLm6, AvrLm7, AvrLm9, AvrLepR1, AvrLepR2 and AvrLmS using a set of differential host genotypes carrying known resistance genes or PCR amplification of AvrLm1, AvrLm6 and AvrLm4-Lm7. Certain alleles were more prevalent in the pathogen population, with AvrLm6 and AvrLm7 present in >85% of isolates, while AvrLm3, AvrLm9 and AvrLepR2 were present in <10% of isolates. A total of 55 races (different combinations of Avr alleles) were detected, with the two most common ones being AvrLm2-Lm4-Lm6-Lm7 and AvrLm2-Lm4-Lm6-Lm7-LmS. Races carrying as many as seven and as few as one known Avr allele were detected. Selection pressure from the race-specific resistance genes carried in canola cultivars has probably played a significant role in the current Avr profile, which may have also contributed to the recent increase in blackleg observed in western Canada. [ABSTRACT FROM AUTHOR]

Background Increasing numbers of children are at-risk for behavioural and emotional disorders, a phenomenon contributing to increased use of pharmacological interventions for paediatric clients. Adverse side effects and other risks associated with pharmacological approaches have helped fuel interest in nutritional interventions for behaviourally at-risk children. Methods The current randomized clinical trial evaluates the efficacy of a neurochemical intervention involving the glutamine and glutamate analogue L-theanine and 5-hydroxytryptophan, the precursor for serotonin, with children adopted from traumatic backgrounds. Results Results include significant increases in urinary levels of the biomarkers for serotonin and gamma-aminobutyric acid, coupled with significant decreases in parent reports of the children's behaviour problems. Conclusions While further research is needed, these initial findings are encouraging and are consistent with a growing number of studies indicating the efficacy of nutritional approaches to help behaviourally at-risk children. [ABSTRACT FROM AUTHOR]

Purpose: To describe the development of a dual track offering for the Adult Health and Gerontology Nurse Practitioner (AGNP) Programs at the University of Pennsylvania School of Nursing and share clinical evaluation tools used with nurse practitioner students in this curriculum. Data sources: Selected research and clinical articles. Conclusions: A variety of evaluation approaches are utilized in the AGNP student clinical performance evaluation. These incorporate the extended clinical practicum sequence for the dual track curriculum in addition to each individual program's objectives. Formative and summative evaluations include reflective logs, clinical documentation of patient encounters, preceptor evaluation, and faculty site visits. Self-evaluative skills of the student and quality faculty feedback are two additional integral components that facilitate learning outcomes in the cognitive, psychomotor, and affective learning domains. Implications for practice: The summary of evaluation tools presented here is an example of how the AGNP Programs at the University of Pennsylvania School of Nursing effectively measure student progress in a curriculum model for dual track enrollment. [ABSTRACT FROM AUTHOR]

Immune tolerance induction (ITI) is described in a patient with severe haemophilia B complicated by the presence of an inhibitor. A number of ITI regimes were attempted without success and the patient suffered from frequent relapses and bleeding episodes. Successful ITI was achieved with the additional use of cyclosporin A. The patient developed nephrotic syndrome although had a negative Bethesda titre at this time. When cyclosporin A therapy was ceased, the inhibitor titre rose and the patient suffered again from bleeding episodes. Cyclosporin A was reintroduced at a lower dose. The patient has now received cyclosporin A for 10 years, during which time he has relapsed three times for short periods (2 weeks). He is also on prophylaxis with factor IX three times a week with preinfusion levels >1% and without bleeding. [ABSTRACT FROM AUTHOR]

Research on theory of mind increasingly encompasses apparently contradictory findings. In particular, in initial studies, older preschoolers consistently passed false-belief tasks-a so-called "definitive" test of mental-state understanding-whereas younger children systematically erred. More recent studies, however, have found evidence of false-belief understanding in 3-year-olds or have demonstrated conditions that improve children's performance. A meta-analysis was conducted (N = 178 separate studies) to address the empirical inconsistencies and theoretical controversies. When organized into a systematic set of factors that vary across studies, false-belief results cluster systematically with the exception of only a few outliers. A combined model that included age, country of origin, and four task factors (e.g., whether the task objects were transformed in order to deceive the protagonist or not) yielded a multiple R of .74 and an R2 of .55; thus, the model accounts for 55% of the variance in false-belief performance. Moreover, false-belief performance showed a consistent developmental pattern, even across various countries and various task manipulations: preschoolers went from below-chance performance to above-chance performance. The findings are inconsistent with early competence proposals that claim that developmental changes are due to tasks artifacts, and thus disappear in simpler, revised false-belief tasks; and are, instead, consistent with theoretical accounts that propose that understanding of belief, and, relatedly, understanding of mind, exhibit genuine conceptual change in the preschool years. [ABSTRACT FROM AUTHOR]

We agree with the commentaries by Scholl and Leslie, and also by Moses, that the meta-analytic findings do not definitively rule out early competence accounts. But they do make extant versions of such accounts increasingly unlikely. In particular, the meta-analytic findings argue against executive function expression accounts, including the Theory-of-Mind Mechanism/Selection Processor account advocated by Scholl and Leslie. Specifically, Scholl and Leslie articulate two explicit predictions of their account: that task manipulations that attenuate inhibitory demands should differentially advantage older children, and that theory-of-mind developments should occur with consistent timetables. Both of these specific predictions are clearly contradicted, not supported, by the meta-analytic findings. [ABSTRACT FROM AUTHOR]

The article discusses the production of freshwater fish for consumption in Eastern European Communities. The statistical data in marketing organization for the freshwater fish are not that highly developed compared to the marine fish, however, in the retail and wholesale market freshwater fish fetches good prices. The production of freshwater fish in Eastern Europe depends largely on carp and other anadromous species.

Some of the ponds in which the ability of grass carp (Ctenopharyngodon idella (Val.)) to control aquatic vegetation was being assessed became infested with Argulus foliaceus L. An analysis of data from two ponds, one infested and the other not infested, both initially stocked with approximately the same fish biomass, together with the data from an earlier experiment as a partial, though imperfect, control indicates that the presence of the parasite caused a decrease in the growth rate and an increase in the mortality rate of the fish. [ABSTRACT FROM AUTHOR]

This paper proposes a curriculum model for nurse education which holds forms of knowledge and interpersonal relationships as key issues if nurse education is to develop autonomous, reflective, critical practitioners. By adopting areas of cognitive interest, principles of andragogy and the concept of reflection-in-action, the model provides a heuristic tool which attempts to enable the provision of a nurse education which is devoted to adult learning processes and relevent to the development of education in the practice setting. The technical, practical and emancipatory areas of cognitive interest provide an understanding of learning domains which require different knowledge bases, methods of learning and forms of assessment to each other. The pedagogy/andragogy dichotomy is presented to reflect two teaching paradigms. The former approach is derived from the activity of teaching children and provides for passive dependence. The latter is more appropriate to adult learning and student self-direction. The model attempts to promote the transitional dynamic which moves the student nurse toward a state of greater self-direction. Finally, the concept of reflection-in-action is discussed in an attempt to ensure that the areas of cognitive interest and the learning strategies are inextricably linked to the practice component of a professional nurse education. All three dimensions are combined to show how each should develop in unison as the professional education of the nurse proceeds along a chronological dimension. [ABSTRACT FROM AUTHOR]

The article reports on the selection of various methods ideal in estimating the size of freshwater fish populations in Towy river in Wales. Several methods are presented to estimate fish population, however, it is decided to use the depletion method since it is usually attainable and desirable. Depletion method is advantageous since the progress of the estimate can be directly evaluated after each fishing.

The article discusses two methods used in estimating the size of fish population in freshwater. Under the multiple census mark-recapture method, the water studied is fished several times and the unmarked fish caught are marked and returned to the water with the assumption that the population size remains constant in the process. While the depletion method lies on a principle that in a closed population, the catch per unit effort will be proportional to the number of fish available to be caught.

The article discusses on the methods of estimating the size of freshwater fish populations in Great Britain. These approaches included mark-recapture and depletion or replicate-fishing that were based on the four factors that governed the size of a fish population. These are breeding of young fish, mortality, fish migration.

Reports on the continuous rising trend of childhood Type 1 diabetes mellitus in Devon and Cornwall, England between 1975 and 1996, based on the Cornwall and Plymouth Children's Diabetes Register. Use of the two-source capture-recapture method to assess the case ascertainment; Childhood population in the study catchment area; Factors attributed to the continuous rising trend of childhood Type 1 diabetes mellitus.

The article cites a study about the use of electrodes in freshwater fishing in Great Britain. The electrode is considered as a substantial improvement in fishing. The design of anode has proved to be easy to handle and robust enough to assist in maneuvering a boat. The weight can be appreciably reduced by obtaining the pole without the polyvinyl chloride former on which the fiber-glass is laid in the manufacturing process.

The measurement of marital or dyadic adjustment remains a problem for researchers. The present study examines one instrument recently devised to reliably classify respondents for research purposes into high- and low-adjustment groups. Data indicate that, while the overall scale performs the stated task reliably, the majority of its 32 items are unnecessary. Factor analysis revealed that there was one under- lying "adjustment" dimension. Previous factor structures were not replicated. [ABSTRACT FROM AUTHOR]

The article discusses about a preliminary study undertaken to assess the frequency of concurrent nickel-induced psoriasis, especially in young women. 350 sequential outpatients with psoriasis, and 600 unmatched patients with miscellaneous rashes, were questioned for a past history of metal sensitivity. 219 females with psoriasis were specifically examined for its evidence at sites of contact with metal items such as costume jewellery and clothes fastenings. Nickel exposure, in patients with psoriasis. may significantly influence its course. An association between the HLA haptotype B35 and nickel allergy has also been noted in persistent pustular psoriasis.

Preliminary bench scale tests indicated that the rate of extraction of oil from glandless cottonseed flakes is about the same as for glanded flakes. Pilot plant experiments, using 20 lb. batches of flakes in baskets 8×8 in. in cross section, showed that the usual percolation rates can be used and will produce the same results with glandless flakes as with glanded. Solvents used were commercial hexane, nearly pure normal hexane, and a mixed solvent of acetone, hexane and water. In some runs raw flakes were extracted; in others, the meats were tempered by heating to various temperatures. Refine and bleach tests were run on the resulting oil. Colors were much lower than generally obtained with oil from glanded seed, most samples testing below one red Lovibond on a spectrophotometer. The meals from the extractions were used in rat feeding tests. The mixed solvent meal seemed to be a cut above the hexane-extracted meals in protein quality, showing up equivalent to a casein based diet. The meal from meats which had been heated to 230 F seemed very slightly inferior to those which had undergone less drastic heating. All glandless meals were much superior to a commercial prepress solvent meal which was run for the purpose of making comparisons. [ABSTRACT FROM AUTHOR]

The aim of this study is to describe the self-reported experiences of adolescents in population-based samples when completing health-related surveys on topics with varying potential for evoking distress. Survey data were collected in three school-based studies of bullying behaviors (N = 1,771, 12-14 years), alcohol use (N = 823, 12, 15, and 17 years), and electronic image sharing (N = 274, 13 years). Between 5% and 15% of respondents reported being upset at survey completion, but at most 1.4% were entirely negative in their evaluation. Age was not associated with being upset, but younger adolescents were more likely to see benefit in participation. Although concurrent mental health symptoms increased the risk of being upset, this was mostly mitigated by perceived benefits from participation., (© 2017 Society for Research on Adolescence.)

Despite the Revised International Prognostic Index's (R-IPI) undoubted utility in diffuse large B-cell lymphoma (DLBCL), significant clinical heterogeneity within R-IPI categories persists. Emerging evidence indicates that circulating host immunity is a robust and R-IPI independent prognosticator, most likely reflecting the immune status of the intratumoral microenvironment. We hypothesized that direct quantification of immunity within lymphomatous tissue would better permit stratification within R-IPI categories. We analyzed 122 newly diagnosed consecutive DLBCL patients treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) chemo-immunotherapy. Median follow-up was 4 years. As expected, the R-IPI was a significant predictor of outcome with 5-year overall survival (OS) 87% for very good, 87% for good, and 51% for poor-risk R-IPI scores (P < 0.001). Consistent with previous reports, systemic immunity also predicted outcome (86% OS for high lymphocyte to monocyte ratio [LMR], versus 63% with low LMR, P = 0.01). Multivariate analysis confirmed LMR as independently prognostic. Flow cytometry on fresh diagnostic lymphoma tissue, identified CD4(+) T-cell infiltration as the most significant predictor of outcome with ≥23% infiltration dividing the cohort into high and low risk groups with regard to event-free survival (EFS, P = 0.007) and OS (P = 0.003). EFS and OS were independent of the R-IPI and LMR. Importantly, within very good/good R-IPI patients, CD4(+) T-cells still distinguished patients with different 5 year OS (high 96% versus low 63%, P = 0.02). These results illustrate the importance of circulating and local intratumoral immunity in DLBCL treated with R-CHOP., (Copyright © 2013 Wiley Periodicals, Inc.)

Background: Connectedness to school is a significant predictor of adolescent health and academic outcomes. While individual predictors of connectedness have been well-described, little is known about school-level factors which may influence connectedness. A school's ecology, or its structural, functional, and built aspects, coupled with interpersonal interactions, may also help to enhance adolescent connectedness., Aim: This study aims to identify school ecological characteristics which predict enhanced connectedness in secondary school., Sample: Data from 5,159 Grade 8 students (12-13 years) from 39 randomly selected schools were tracked until the end of Grade 9 (13-14 years)., Method: Students' self-reported school, teacher, and family connectedness, mental health and peer relationships were measured at two time points. Accounting for school-level clustering, student- and school-level ecological characteristics were modelled on self-reported school connectedness in Grades 8 and 9., Results: Students' higher school connectedness in Grades 8 and 9 was influenced by greater levels of family connectedness, fewer classroom and peer problems, less difficult secondary school transition, fewer emotional problems, and greater prosocial skills. Seven school-level ecological variables were significantly associated with school connectedness after controlling for student-level predictors. At the school-level, priority for pastoral care and students' aggregated writing skills scores significantly predicted concurrent and future enhanced connectedness., Conclusions: Interventions to improve students' school connectedness should address individual student characteristics and school functional features such as pastoral care strategies and helping students to achieve greater academic outcomes. Future studies should focus on the cumulative longitudinal influence of school ecological and student-level predictors of school connectedness.

Introduction and Aims: Declines in adolescent smoking prevalence have slowed recently, resulting in increased interest and literature in tobacco harm minimisation. To date, harm reduction strategies have focused largely on modifying the product and alternative (safer) mechanisms of nicotine delivery. There has been little exploration of primary harm minimisation to prevent the onset of regular smoking among young people. A major concern expressed about harm reduction interventions and young people is that they may increase experimentation among non-users., Design and Methods: The Smoking Cessation for Youth Project was a 2-year school-based cluster randomised controlled trial conducted in 30 Western Australian schools. Results on the primary outcome showed a significant reduction in regular smoking among 4636 13-15-year-olds receiving a harm minimisaton versus standard intervention. This paper addresses the intervention effects on 2078 students who had not smoked at baseline., Results: At 20-month follow-up, smoking initiation was slightly lower among intervention students than comparison students (who received a largely abstinence-based intervention), although this difference did not attain statistical significance (OR=0.86; 95% confidence interval: 0.68, 1.09)., Discussion and Conclusions: This study provided limited evidence to suggest that harm minimisation is a superior approach to abstinence-based interventions for non-smokers. However, this intervention did not contribute to increased experimentation among non-smokers. Although more trials are required, these results indicate that fears of potential negative iatrogenic effects from school-based harm minimisation interventions may be unwarranted.

Aims: To determine the impact of a school-based harm minimization smoking intervention compared to traditional abstinence-based approaches., Design, Setting and Participants: A school-based cluster randomized trial was conducted in Perth, Western Australia in 30 government high schools from 1999 to 2000. Over 4000 students were recruited to participate and schools were assigned randomly to either the harm minimization intervention or a standard abstinence-based programme., Intervention: The harm minimization intervention comprised eight 1-hour lessons over 2 years, quitting support from school nurses and enactment of policies to support programme components. Comparison schools implemented standard abstinence-based programmes and policies., Measures: Cigarette smoking was categorized at two levels: regular smoking, defined as smoking on 4 or more days in the previous week; and 30-day smoking as any smoking within the previous month., Findings: At immediate post-test (20 months post-baseline), after accounting for baseline differences, school-level clustering effects, socio-economic status, gender and family smoking, intervention students were less likely to smoke regularly [OR = 0.51, 95% confidence interval (CI) = 0.36, 0.71] or to have smoked within the previous 30 days (OR = 0.69, 95% CI = 0.53, 0.91)., Conclusion: The school-based adolescent harm minimization intervention appears to have been more effective than the abstinence-based social influences programme at reducing regular smoking.

It has been demonstrated that microtubule-associated proteins (MAPs) interact with tubulin in vitro and in vivo. However, there is no clear evidence on the possible roles of the interactions of MAPs in vivo with other cytoskeletal components in maintaining the integrity of the cell architecture. To address this question we extracted the neuronal cytoskeleton from brain cells and studied the selective dissociation of specific molecular isospecies of tau protein under various experimental conditions. Tau, and in some cases MPA-2, were analysed by the use of anti-idiotypic antibodies that recognize epitopes on their tubulin binding sites. Fractions of microtubule-bound tau isoforms were extracted with 0.35 M NaCl or after the addition of nocodazole to allow microtubule depolymerization. Protein eluted with this inhibitor contained most of the assembled tubulin dimer pool and part of the remaining tau and MAP-2. When the remaining cytoskeletal pellet was treated with cytochalasin D to allow depolymerization of actin filaments, only tau isoforms were extracted. Immunoprecipitation studies along with immunolocalization experiments in cell lines containing tau-like components supported the findings on the roles of tau isospecies as linkers between tubulin in the microtubular structure with actin filaments. Interestingly, in certain types of cells, antibody-reactive tau isospecies were detected by immunofluorescence with a discrete distribution pattern along actin filaments, which was affected by cytochalasin disruption of the actin filament network. These results suggest the possible in vivo roles of subsets of tau protein in modulating the interactions between microtubules and actin filaments.

The aims of this study were to investigate the prevalence and severity of periodontal diseases in HIV seropositive and assumed HIV seronegative individuals in the Edinburgh area. 29 HIV seropositive subjects were examined at baseline and at 3-monthly intervals. Attachment loss and dichotomous indicators of periodontal disease were recorded. 27 control subjects were seen at baseline only. Although there was no significant difference between the 2 groups in terms of mean attachment loss at baseline, HIV seropositive subjects had experienced more severe attachment loss localised to the lower incisor region. HIV seropositive subjects had a significantly higher mean % of sites exhibiting suppuration and redness. A distinct subgroup of 9 HIV seropositive subjects with widespread attachment loss was detected, which included those subjects with severely affected lower incisors. Site-specific attachment loss of > or = 3 mm was observed in only 20 sites out of 2814 sites in HIV+subjects observed longitudinally. The incidence of aggressive periodontal disease in this study was lower than anticipated, despite the inclusion of patients with advanced HIV infection or AIDS.

The aims of this study were to compare the prevalence of suspected periodontal pathogens in subgingival plaque from 29 HIV seropositive and 27 control subjects and to determine the association of these bacteria with periodontal destruction. Subgingival plaque was collected from the mesiobuccal sites of all teeth, except 3rd molars. Bacteria were identified and enumerated using non-isotopic whole chromosomal DNA probes and a colony lift method. At baseline, HIV seropositive subjects had significantly higher mean % of Porphyromonas gingivalis than control subjects. This difference could be attributed to a subgroup of HIV seropositive subjects with widespread attachment loss. No correlations were observed between the mean %s of DNA probe species and mean attachment loss, CD4 and CD8 T lymphocyte counts or CD4: CD8 ratio. No significant microbiological differences were detected between active and control sites in HIV seropositive subjects on a longitudinal basis. There appeared to be an inverse relationship between the mean %s of P. gingivalis and V. parvula, with respect to progression of HIV infection. The ability of microbiological parameters to predict site-specific breakdown in HIV seropositive subjects requires further investigation.

Human subjects indicated their preference between a hypothetical $1,000 reward available with various probabilities or delays and a certain reward of variable amount available immediately. The function relating the amount of the certain-immediate reward subjectively equivalent to the delayed $1,000 reward had the same general shape (hyperbolic) as the function found by Mazur (1987) to describe pigeons' delay discounting. The function relating the certain-immediate amount of money subjectively equivalent to the probabilistic $1,000 reward was also hyperbolic, provided that the stated probability was transformed to odds against winning. In a second experiment, when human subjects chose between a delayed $1,000 reward and a probabilistic $1,000 reward, delay was proportional to the same odds-against transformation of the probability to which it was subjectively equivalent.

The sequelae following prolonged tracheal intubation are reviewed. The virtues of large volume low pressure cuffs are confirmed, and the dynamic variations of pressure both within the airway and within the cuff of standard and floppy cuffed tubes have been re-appraised.