The independence of endogenous and exogenous temporal attention.

Temporal attention is the focusing of perceptual resources at a particular point in time. Valid temporal cue information has the capability to improve performance by reducing reaction times, while invalid information has the possibility of impairing performance. The performance difference between valid and invalid conditions is called a temporal cueing effect (TCE). We explored how different alerting mechanisms interact with a participant's ability to utilize temporal information cues, using the Kingstone (The Quarterly Journal of Experimental Psychology, 44(1), 69-104, 1992) temporal cueing paradigm. Extracting the alerting procedure from Lawrence and Klein (Journal of Experimental Psychology: General, 142(2), 560-572, 2013), one of two different temporally contingent warning signals were presented to participants during a trial. The "hi-intensity" warning signal increases intensity and elicits both exogenous and endogenous alerting mechanisms. The "no-intensity" warning signal is isointense relative to baseline and elicits only endogenous alerting mechanisms. Two experiments conducted previously using a discrimination task showed interference between the signal intensity and task difficulty, where the "no-intensity" signal failed to elicit TCEs. In the present study, we implemented a detection task, reducing the mental effort required for a response. The results showed equal TCEs in both signal conditions. We argue for independence of these alerting mechanisms, by way of Sternberg's (Acta Psychologica, 30, 276-315, 1969) additive factor method. Arguments contrasting what mechanism is being impacted by this paradigm are further outlined.

Long-term outcome of expanded newborn screening at Boston children's hospital: benefits and challenges in defining true disease.

INTRODUCTION: There is no universal consensus of the disorders included in newborn screening programs. Few studies so far, mostly short-term, have compared the outcome of disorders detected by expanded newborn screening (ENBS) to the outcome of the same disorders detected clinically. METHODS: We compared the clinical and neurodevelopmental outcomes in patients with metabolic disorders detected by ENBS, including biotinidase testing, with those detected clinically and followed at the Metabolism Clinic at Boston Children's Hospital. RESULTS: One hundred eighty-nine patients came to attention from ENBS and 142 were clinically diagnosed. 3-methylcrotonyl-CoA carboxylase, biotinidase, and carnitine deficiencies were exclusively identified by ENBS and medium chain acyl-CoA dehydrogenase (MCADD) and very long chain acyl-CoA dehydrogenase deficiencies (VLCADD) were predominantly identified by ENBS whereas the organic acid disorders more often came to attention clinically. Only 2% of the ENBS-detected cases had clinically severe outcomes compared to 42% of those clinically detected. The mean IQ score was 103 + 17 for the ENBS-detected cases and 77 + 24 for those clinically detected. Those newly included disorders that seem to derive the greatest benefit from ENBS include the fatty acid oxidation disorders, profound biotinidase deficiency, tyrosinemia type 1, and perhaps carnitine deficiency. CONCLUSION: Although the NBS-identified and clinically-identified cohorts were not completely comparable, this long-term study shows likely substantial improvement overall in the outcome of these metabolic disorders in the NBS infants. Infants with mild disorders and benign variants may represent a significant number of infants identified by ENBS. The future challenge will be to unequivocally differentiate the disorders most benefitting from ENBS and adjust programs accordingly.

Shrinking the food-print: A qualitative study into consumer perceptions, experiences and attitudes towards healthy and environmentally friendly food behaviours.

Internationally, there is increasing recognition of the importance of multilevel policies and actions that address healthy and environmentally friendly food behaviours. However it is not yet clear which actions are most suitable to support consumers to adopt both behaviours concurrently. To this end, we undertook a qualitative study to assess consumer perceptions, experiences and attitudes towards healthy and environmentally friendly foods and four target behaviours: reducing overconsumption of food beyond energy needs, reducing consumption of low-nutrient energy dense foods, eating less animal- and more plant-derived foods, and reducing food waste. Online in-depth interviews were held with 29 Australian food shoppers representing different levels of involvement with health and environment in daily food choices. The results indicate that compared to health, the relationship between food and the environment is rarely considered by consumers. The four target food behaviours were primarily associated and motivated by an impact on health, except for not wasting foods. Participants had the most positive attitude and highest motivation for eating less processed and packaged foods, mostly to avoid excessive packaging and 'chemicals' in foods. This was followed by the behaviours reducing food waste and overconsumption. Conversely, there was a predominantly negative attitude towards, and low motivation for, eating less animal-derived products and more plant based foods. Overall, consumers found a joined concept of healthy and environmentally friendly foods an acceptable idea. We recommend that health should remain the overarching principle for policies and actions concerned with shifting consumer behaviours, as this personal benefit appears to have a greater potential to support behaviour change. Future consumer focused work could pay attention to framing behavioural messages, providing intermediate behavioural goals, and a multiple target approach to change habitual behaviours.

Evidence of differences in the biotransformation of organic contaminants in three species of freshwater invertebrates.

Acute static bioassays were performed using three freshwater invertebrate species (the oligochaete Lumbriculus variegatus, the fingernail clam Sphaerium corneum and the larvae Chironomus riparius) exposed separately to a variety of 14C radiolabelled contaminants. The aim of this work was to investigate if the chemicals remained as parent compounds after the treatments. Chemicals used were 2,4-dichlorophenol; 2,4,5-trichlorophenol; pentachlorophenol; pyrene; Fenpropidin, and Trifluralin. Homogenates of the whole body tissue of each organism were prepared and total radioactivity was measured. Contaminants were then extracted into organic solvents and analysed by high-pressure liquid chromatography techniques. Chromatograms showed that most of the substances extracted were present as parent compounds in S. corneum and in L. variegatus. In contrast, for C. riparius a low proportion of the chemicals was recovered as parent compounds. These results suggest that different metabolic processes could take place in the different species.

The use of sediment analogues to study the uptake of pollutants by chironomid larvae.

A technique is described that uses artificial resin beads with known surface properties to investigate the factors influencing the bioaccumulation of pollutants from sediments. One advantage of this technique is that it provides a standard procedure against which it is possible to calibrate natural sediments with their diverse properties. The method has been used on third instar larvae of the midge Chironomus riparius and the results are compared with previous studies on the worm Lumbriculus variegatus. The use of a standard test using resin beads as a substitute for natural sediment allows comparisons to be made between species and substrates. Thus, the bioaccumulation factors for the midge larvae are much smaller than those of the worm and this correlates with the ability of the insect larva to detoxify many pollutants. It is also possible to use the test to identify if ingestion of the sediment increases the bioaccumulation of contaminants and whether this involves the release of pollutants by digestive processes or not.

Can adsorption isotherms predict sediment bioavailability?

The adsorption and desorption of 2,4-dichlorophenol (DCP) and pentachlorophenol (PCP) were studied for a range of synthetic particles, a dimethylditallowammonium exchanged clay and a natural sediment. The synthetic particles were Dowex 1X8400, Toyopearl Phenyl 650M and Toyopearl SP 650M. The bioaccumulation of the DCP and PCP from these particles was then studied using the oligochaete, Lumbriculus variegatus. There is a correlation between contaminant-particle interactions, as determined from adsorption and desorption isotherms, and bioaccumulation. Bioaccumulation by L. variegatus was found to be highest from the systems where differences in the classification of adsorption and desorption isotherms were observed.

Tube gastrostomy after radical cystectomy and urinary diversion: surgical technique and experience in 709 patients.

We describe our surgical technique of tube gastrostomy and report our experience with 709 patients who underwent cystectomy and urinary diversion with gastrostomy tube placement from January 1988 to December 1997. This modified Stamm technique provides an effective means of gastric decompression without the discomfort associated with nasogastric decompression, is associated with a low complication rate (0.05%), and may be considered as the procedure of choice when gastric drainage is required after radical cystectomy and lower urinary tract reconstruction.

Iododoxorubicin in advanced breast cancer: a phase II evaluation of clinical activity, pharmacology and quality of life.

Iododoxorubicin 80 mg m-2 i.v. was given 3 weekly for a maximum of six cycles as first-line chemotherapy to 14 evaluable women with metastatic breast cancer. The response rate was 14% (95% confidence intervals 4-40%); median time to progression was 3.5 months (range 0.7 to > 9.3) and median survival was 10.2 months (range 2.3 to > 20.4). Neutropenia was the main toxicity but was not associated with severe sepsis. Two patients had a significant (> 10%) but asymptomatic fall in cardiac ejection fraction; other toxicities were mild. Plasma pharmacokinetics was studied during the first cycle of treatment. Iododoxorubicin was extensively metabolised to iododoxorubicinol. Neutropenia and thrombocytopenia were both significantly correlated with the area under the concentration-time curve (AUC) for iododoxorubicin and the total AUC for iododoxorubicin and iododoxorubicinol. Quality of life (QOL), evaluated by self-report questionnaire and interview, showed little evidence of benefit in terms of physical symptom relief, level of activity, psychological symptoms or global evaluation of QOL during treatment. Iododoxorubicin is subjectively less toxic than standard anthracyclines, but at the dose and schedule used has limited activity in metastatic breast cancer, possibly because iododoxorubicinol is not clinically active.

Local excision for selected colorectal carcinomas.

In summary, local excision is a useful tool in the management of selected colorectal carcinomas. The advent of the fibreoptic colonoscope has revised the concept of local excision when dealing with carcinoma-containing polyps of the colon. The clinician now has the means of locally excising certain carcinomas which would have required laparotomy in the not so distant past. In dealing with carcinoma of the rectum, local excision is not advocated for all rectal carcinomas. In fact, when the previously discussed tumour related factors are considered, local excision should be the ultimate procedure in less than 5% of operations performed for rectal carcinomas. However, when appropriately used, local excision provides a less morbid alternative to more radical procedures without compromising patient survival rates or local recurrence rates.

Lower gastrointestinal bleeding. A systematic approach to classification and management.

Early classification of lower gastrointestinal bleeding as occult, minor overt, or major overt allows a practical approach to evaluation and management. Localization of the bleeding site is the next step. In occult and minor overt bleeding, the cause can usually be determined from results of conventional diagnostic tests; however, angiography and even intraoperative endoscopy may be necessary in some particularly difficult cases. In contrast, major overt bleeding may only allow time for angiographic localization before surgery. Using this approach, the primary care physician can successfully manage most patients with lower gastrointestinal bleeding.

Reference concentrations of serum selenium and manganese in healthy nulliparas.

Reference serum selenium and manganese concentrations were established for healthy nulliparas aged 18-23 years resident in Cape Town. Measurements were determined for selenium in 100 female students who had been taking low-dosage triphasic contraceptive medication for a minimum of 3 months and in 100 female students who were not on contraceptive therapy. Manganese concentrations were determined for 25 female students from each group. The mean serum selenium concentrations were 0.988 +/- 0.189 micrograms/l (78 +/- 15 micrograms/dl) and 0.925 +/- 0.177 mumol/l (73 +/- 14 micrograms/l) respectively for females taking and not taking oral contraceptives. The corresponding concentrations for manganese were 21.84 +/- 9.82 nmol/l (1.20 +/- 0.54 micrograms/l) and 21.66 +/- 7.64 nmol/l (1.19 +/- 0.42 micrograms/l) respectively. The differences in selenium were statistically significant (P = 0.0231) but not for manganese (P = 0.910).

Reference values for serum copper, ceruloplasmin and zinc and haematological indices for healthy nulliparous females.

Reference serum copper, ceruloplasmin and zinc values were established for 100 healthy white nulliparous students aged 18-23 years resident in Cape Town who had been taking low-dosage triphasic contraceptives for a minimum period of 3 months, and in 100 female students not taking contraceptives. The mean serum copper values were 26.5 +/- 4.2 mumol/l and 16.9 +/- 2.7 mumol/l for those taking and not taking oral contraceptives respectively; corresponding values for ceruloplasmin were 181 +/- 43.9 IU/ml and 110 +/- 22.7 IU/ml respectively. Both differences were statistically significant. Serum zinc values for those on contraceptives were 14.1 +/- 2.1 mumol/l and for the others 14.7 +/- 2.0 mumol/l. There were no differences in the haematological parameters except for a significantly higher mean corpuscular volume in females taking oral contraceptives. Of possible clinical significance in this student population are prevalence rates of 2.2% for anaemia (haemoglobin value less than 11.5 g/dl), 7% for iron deficiency (serum ferritin less than 12 micrograms/l) and 6.6% for iron depletion (serum ferritin 12-20 micrograms/l).