New Directions in Water Research: IWMI at the Threshold of the Twenty-first Century

The International Water Management Institute (IWMI) has made important changes in the thrust of its research programmesince 1995. These new thrusts include attention to the implications of increasing water scarcity at the global level; the adoption of a river basin paradigm leading to new insights into opportunities for water conservation and productivity; application of new information technologies and quantitative analytical techniques; and a stronger focus on policy, institutional issues, health and environment, and social inequities in access to water. This paper describes these changes and provides an overview of the remaining papers in this special issue of Water Resources Development.     

Effect of trichloroethylene on the exploratory and locomotor activity of rats exposed during development

Trichloroethylene (TCE) is a common contaminant of underground water supplies. To examine the effect of TCE on the developing central nervous system, rats were exposed to TCE throughout gestation until 21 days postpartum via their dams' drinking water. TCE concentrations of 312 mg/l, 625 mg/l and 1250 mg/l were tested. Exploratory behavior was higher in 60- and 90-day old male rats which were exposed to any level of TCE. The effect of TCE-exposure on locomotor activity (running wheel) was also examined in 60-day old males (625 and 1250 ppm exposure groups). Locomotor activity was significantly higher in rats exposed to 1250 ppm TCE. These data suggest that TCE has long-term effects on behaviour.     

Temperament and attention: Orienting toward and away from positive and negative signals.

Two studies used a target detection task to examine temperament-related attentional biases toward and away from significant stimuli. Pretarget cues were used to orient attention to locations carrying a positive incentive value (where points could be gained) or a negative value (where points could be lost). Under both involuntary and voluntary conditions, extraverts were slow to shift attention away from positive locations, whereas introverts were slow to shift from negative locations. These biases were enhanced on trials following negative feedback and tended to be strongest in Ss high in Neuroticism. The findings support models proposing that Extraversion reflects the combined activity of positive (strongest in extraverts) and negative (strongest in introverts) incentive motivational processes. They further suggest that incentive processes regulate the ability to shift attention away from, rather than toward, significant stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Anaphylaxis in Association with Heparin-Induced Thrombocytopenia

Heparin is almost universally used as an anticoagulant during hemodialysis. Rare but serious side effects of heparin therapy include heparin‐induced thrombocytopenia (HIT) and anaphylaxis, and these may lead to significant mortality and morbidity if left unrecognized. We are reporting a patient who developed HIT followed by an anaphylactoid reaction. This 8‐year‐old girl with Joubert's syndrome developed end‐stage renal disease secondary to nephronophthisis. She had a Permacath double‐lumen hemodialysis catheter placed in the right internal jugular vein and was started on hemodialysis using an Asahi B10 65 Dialyzer on 1/28/03. The platelet count at that time was 246 × 10³/mL. Beef lung heparin was used for anticoagulation. She was admitted for living related donor renal transplant on 2/10/03 but was found to be thrombocytopenic with a platelet count of 49 × 10³/mL. The transplant was postponed, a sepsis work‐up was performed, and she was started on antibiotics pending culture results. Hemodialysis was continued with heparin anticoagulation, and despite an improvement in the platelet count she had an acute anaphylactoid reaction 2 days later. The reaction occurred 20 min after starting her hemodialysis treatment and presented as acute onset of bronchospasm, agitation, and chest discomfort. She improved with nebulized albuterol and subcutaneous epinephrine. A review of her records revealed that she had received 6 hemodialysis treatments. The platelet count on 2/3/03, after 3 hemodialysis treatments, had been 242 × 10³/mL and on 2/8/03 after 5 treatments the platelet count was 72 × 10³/mL. HIT with anaphylaxis was suspected. Heparin was discontinued and the platelet count had returned to normal within 2 days. The diagnosis was confirmed by a positive heparin‐associated antibody test. While HIT is recognized as a complication in 1–5% of patients treated with heparin and has been well described in the literature, we could only find 2 reported cases of heparin‐induced anaphylaxis and in both cases there was accompanying thrombocytopenia. This patient further illustrates a possible linkage between these two phenomena. HIT is an important cause of thrombocytopenia in a patient on hemodialysis and continued exposure to heparin may induce anaphylaxis.     

A possible structure of the casein micelle based on high-resolution field-emission scanning electron microscopy

New electron micrographs, produced using the technique of Field Emission Scanning Electron Microscopy, showing the details of the micellar surface, are presented. The images show the micellar surfaces without any coating, and suggest that the surface of the micelle may have a much more complex structure than has previously been demonstrated. Although there appear to be no spherical subunits (submicelles), there is evidence for the organization of the caseins into tubular structures within the micelle. The surface is not smooth, and contains gaps between the substructures. The observations are discussed in terms of published models of micellar structure, where is it suggested how the depiction of the micellar surface can be used to explain certain factors of its reactivity and behaviour.     

Effects of three crosslinkers on colored pH‐responsive core–shell latexes

Environmentally responsive hydrogels have become attractive research subjects for many applications. In this work, a series of pH‐sensitive and color‐changing nanoparticles (nanogels) with core–shell structures were synthesized. The cores were blue latex particles synthesized by a miniemulsion technique with styrene and methacrylic acid as monomers and Neozapon Blue 807 as a dye. The shell was a pH‐sensitive polymer that was precipitation‐polymerized onto the core from 2‐(diethylamino) ethyl methacrylate with N,N′‐methylenebisacrylamide, poly(propylene glycol) diacrylate, and divinylbenzene as crosslinking agents. In the resultant latexes, the color was observed to change from deep blue to pale blue as the pH of the system was changed from a high of 10 to a low of 3. The synthesized latexes and particles (gels) were then characterized with an ultraviolet–visible spectrometer, dynamic light scattering, Fourier transform infrared, and nuclear magnetic resonance. Atomic force microscopy was also used to investigate the different morphologies of the particles after the synthesized latexes were dried at different pH values. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Gender moderates the relationship between testosterone and marital interaction.

Higher testosterone levels are related to assertiveness and dominance. Given the relevance of those behavioral correlates to spouses' daily transactions, links between testosterone levels and marital interaction were explored among 92 newlywed couples. Marital problem-solving and social support transactions were assessed, and saliva was collected and assayed for testosterone. Whether marital behavior was related to husbands' and wives' testosterone levels was examined. The link between spouses' testosterone and their behavior was contingent on the partner's testosterone levels. Husbands exhibited more adaptive problem-solving behaviors and social support provision when husbands and wives were concordant for lower testosterone levels. In contrast, wives exhibited more adaptive support provision when spouses had discordant testosterone levels such that wives had higher levels and husbands had lower levels. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A Multisite Comparison of Actuarial Risk Instruments for Sex Offenders.

Four actuarial instruments for the prediction of violent and sexual reoffending (the Violence Risk Appraisal Guide [VRAG], Sex Offender Risk Appraisal Guide [SORAG], Rapid Risk Assessment for Sex Offender Recidivism [RRASOR], and Static-99) were evaluated in 4 samples of sex offenders (N = 396). Although all 4 instruments predicted violent (including sexual) recidivism and recidivism known to be sexually motivated, areas under the receiver operating characteristic (ROC) were consistently higher for the VRAG and the SORAG. The instruments performed better when there were fewer missing items and follow-up time was fixed, with an ROC area up to .84 for the VRAG, for example, under such favorable conditions. Predictive accuracy was higher for child molesters than for rapists, especially for the Static-99 and the RRASOR. Consistent with past research, survival analyses revealed that those offenders high in both psychopathy and sexual deviance were an especially high-risk group. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Smoking Withdrawal Dynamics: III. Correlates of Withdrawal Heterogeneity.

Five parameters of postcessation smoking withdrawal variability derived from clinical data (T. M. Piasecki, D. E. Jorenby, S. S. Smith, M. C. Fiore, & T. B. Baker, 2003a, 2003b) were predicted from baseline measures and pharmacotherapy assignment. Smokers who were more dependent, older, and high in negative affect reported more severe withdrawal. Women, heavier smokers, and those with a history of depression reported more variable symptoms. Smokers treated with nicotine patch, bupropion, or both reported less severe withdrawal than did those given placebo, but medication did not affect the slope of symptoms over time, day-to-day variability of symptoms, or the size of acute changes in symptoms associated with lapses to smoking. Prior research has shown that these symptom facets predict later relapse: thus, current pharmacotherapies may aid cessation by diminishing withdrawal severity, but they do not affect all clinically important aspects of withdrawal. (PsycINFO Database Record (c) 2010 APA, all rights reserved)