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Acipenserids (sturgeons) live in large rivers and lakes in North America and Eurasia, where many species and populations are considered imperiled. One of the most pervasive threats across the global range of sturgeon is water resource development (e.g., hydropower dams, water intakes for irrigation, industrial use, or human consumption). We report on the outcome of a literature review focused on interactions between sturgeon and water resource development. We focused on the persistent issue of dam passage (both upstream and downstream), impingement, and entrainment, which are all relevant issues for both existing and planned facilities. We discuss aspects of sturgeon sensory physiology, and how knowledge of sensory physiology can be used for behavioural guidance. We also consider how the swimming ability and style of sturgeon is relevant for passage. Most of the literature emanated from research on just a few species (especially lake sturgeon, white sturgeon, green sturgeon, and shortnose sturgeon). Although there are several examples of apparent "success stories" (e.g., successful upstream fish passage, efforts to reduce impingement and entrainment), there are also many failures, and such examples are likely under-reported. Without significant investments in solutions-oriented research related to sturgeon-water resource development interactions, we submit that fish passage, entrainment and impingement problems for acipenserids will remain. There is a need for research that spans life-stages, compares different species, and considers how passage, entrainment, and impingement influence demography. Further, there is a need for investment into evidence-based implementation of mitigation infrastructure and management strategies to ensure conservation needs of sturgeons are adequately considered. [ABSTRACT FROM AUTHOR]

Background: The Mid-West of Ireland has higher than average national rates of invasive extended-spectrum beta-lactamase (ESBL) bloodstream infections and carbapenemase-producing Enterobacteriaceae (CPE), with increasing numbers of ESBL isolates detected in community-dwelling patients. Aims: To conduct a point prevalence study in a convenience sample of the Mid-West population with the aim of determining the extent of ESBL colonisation. Methods: Utilising anonymised community stool samples that had completed routine analysis, we conducted a point prevalence study over a 4-week period on all samples that met defined inclusion and exclusion criteria. Limited epidemiological data was recorded: (1) age of patient, (2) gender, and (3) sender location. From these stool specimens, rectal swabs were inoculated (eSwab™ 480CE, Copan, Italy), which were subsequently cultured on selective chromogenic agar (Colorex™ ESBL). Culture plates were incubated aerobically at 37 °C for 24 h. Results: Of 195 samples processed, 58 % ( n = 112) were from females. The median patient age was 62.4 years (range 20-94 years). 186 samples (95 %) originated from general practitioner clinics. During the study period, only nine eligible stool samples were received from LTCF (6 public). From 195 Colorex™ ESBL chromogenic agar plates cultured, no ESBL-producing organisms were detected. Conclusions: This community point prevalence study did not identify ESBL colonisation despite high numbers of patients with invasive ESBL bloodstream infections presenting for admission in our institution. We believe this may be because of our small sample size. Data regarding antimicrobial exposure and other risk factors for ESBL colonisation were also not available. We remain vigilant for ESBL-producing organisms. [ABSTRACT FROM AUTHOR]

Background: Type 1 diabetes mellitus (T1DM) is a recognised risk factor for cardiometabolic disease. Other risk factors include age, gender, family history, glycaemic control, dyslipidaemia, weight, and activity levels. Aims: To estimate the point prevalence of cardiometabolic risk factors in a paediatric population with T1DM. Methods: Eighty-one patients with T1DM aged between 10 and 16 years attended during the study and 56 (69.1 %) patients agreed to participate. Mixed methods data collection included a questionnaire developed for this study, supplemented by retrospective and prospective data collected from the patient records. Results: Of 56 subjects with T1DM, aged 12.7 ± 1.7 years (10-16 years) 26 were male and 30 were female. Mean HbA1c was 72 ± 14 mmol/mol. 53 subjects (94.6 %) had at least one additional cardiometabolic risk factor. Conclusions: Cardiometabolic risk factors are present in this population with T1DM. Identifying cardiometabolic risk factors in adolescent T1DM patients is the first step in prevention of future morbidity and mortality. [ABSTRACT FROM AUTHOR]

Mitochondrial disorders are a clinically and biochemically diverse group of disorders which may involve multiple organ systems. General anaesthesia (GA) poses a potential risk of decompensation in children with mitochondrial disorders, and there is little guidance for anaesthetists and other clinicians regarding the optimal anaesthetic agents and perioperative management to provide to patients with mitochondrial disease[15]. The aim of this review was to document adverse events and perioperative complications from GA in patients with genetically confirmed mitochondrial disorders. A retrospective chart review of patients with genetically confirmed mitochondrial disorders who had undergone GA was undertaken. The indication for GA, anaesthetic agents utilised, length of admission and post anaesthetic complications were documented and analysed. Twenty-six patients with genetically proven mitochondrial disease underwent 65 GAs. Thirty-four (52%), received propofol as their induction agent. Thirty-three (51%) patients received sevoflurane for the maintenance of anaesthesia, while 8 (12%) received isoflurane and 24 (37%) received propofol. The duration of most GAs was short with 57 (87%) lasting less than 1 h. Perioperative complications occurred in five patients while under GA including ST segment depression, hypotension and metabolic acidosis in one. All five patients were stabilised successfully and none required ICU admission as a consequence of their perioperative complications. The duration of hospital stay post GA was <24 h in 25 (38%) patients.Conclusion: No relationship between choice of anaesthetic agent and subsequent perioperative complication was observed. It is likely that individual optimisation on a case-by-case basis is more important overall than choice of any one particular technique. What is Known: • General anaesthesia (GA) poses a potential risk of decompensation in children with mitochondrial disorders. • There is a great diversity in the anaesthetic approaches undertaken in this cohort, and little guidance exists for anaesthetists and other clinicians regarding the optimal anaesthetic agents and perioperative management to provide to patients with mitochondrial disease. What is New: • In this study of 26 patients with genetically confirmed mitochondrial disease who underwent 65 GAs, no relationship between choice of anaesthetic agent and subsequent perioperative complication was observed • It is likely that individual optimisation on a case-by-case basis is more important overall than choice of any one particular technique. [ABSTRACT FROM AUTHOR]

Introduction: Adequate bowel preparation is necessary for a complete colonoscopy. Polyethylene glycol-electrolyte oral solution (PEG-EOS), sodium picosulphate (SS) and sodium biphosphonate (SP) are the three most commonly used purgative agents. We aimed to determine their efficacy and tolerability compared to each other in a randomised study. Methods: 313 patients were randomly assigned to receive either PEG-EOS, SS or SP. Patients completed a tolerability score pre-colonoscopy. A cleanliness score was used to document adequacy of bowel preparation. A separate group of patients completed taste scores for the three cathartic agents before and after addition of flavour. Results: PEG-EOS was the worst-tolerated regimen but achieved the highest rates of right colonic cleansing and the lowest rate of incomplete colonoscopies. There were no statistical differences in the rates of rectosigmoid and mid-gut cleansing among the three agents. SS was by far the preferred purgative in the taste assessment study. Addition of flavour increased significantly taste scores for PEG-EOS. Conclusion: For adequate bowel cleansing PEG-EOS is the most effective but is the least tolerated and least preferred among patients. Addition of flavour increases significantly patients' acceptance of PEG-EOS. [ABSTRACT FROM AUTHOR]

The advancement of the drug-eluting stent technology raises the significant challenge of safe mechanical design of polymer coated stent systems. Experimental images of stent coatings undergoing significant damage during deployment have been reported; such coating damage and delamination can lead to complications such as restenosis and increased thrombogenicity. In the current study a cohesive zone modeling framework is developed to predict coating delamination and buckling due to hinge deformation during stent deployment. Models are then extended to analyze, for the first time, stent-coating damage due to webbing defects. Webbing defects occur when a bond forms between coating layers on adjacent struts, resulting in extensive delamination of the coating from the strut surfaces. The analyzes presented in this paper uncover the mechanical factors that govern webbing induced coating damage. Finally, an experimental fracture test of a commercially available stent coating material is performed and results demonstrate that the high cohesive strength of the coating material will prevent web fracture, resulting in significant coating delamination during stent deployment. [ABSTRACT FROM AUTHOR]

Objectives: To explore the association between vitamin B12 deficiency and dementia in patients at high risk for vitamin B12 deficiency. Design: Chart review. Setting: Emergency, critical care/trauma, neurology, medicine, and rehabilitation units of two hospitals in Southwestern Ontario, Canada. Participants: Adult patients (n = 666) admitted from 2010 to 2012. Data collection included: reason for admission, gender, age, clinical signs and symptoms of B12 deficiency, serum B12 concentration, and B12 supplementation. Patients with dementia were identified based on their medication profile and medical history. Vitamin B12 deficiency (pmol/L) was defined as serum B12 concentration <148; marginal deficiency: ≥148-220 and adequate >220. Comparisons between B12-deficient patients with and without dementia were examined using parametric and non-parametric tests. Results: Serum B12 values were available for 60% (399/666) of the patients, of whom 4% (16/399) were B12-deficient and 14% (57/399) were marginally deficient. Patients with dementia were not more likely to be B12-deficient or marginally deficient [21% (26/121)] compared to those with no dementia [17% (47/278), p=0.27)]. Based on documentation, 34% (25/73) of the B12-deficient and marginally-deficient patients did not receive B12 supplementation, of whom 40% (10/25) had dementia. Conclusion: In this sample of patients, there was no association between B12 deficiency and dementia. However, appropriate B12 screening protocols are necessary for high risk patient to identify deficiency and then receive B12 supplementation as needed. [ABSTRACT FROM AUTHOR]

The microstructures of concentrated aqueous solutions of n-butyl( n-dodecyl)phosphate (BDoP) and n-hexyl( n-dodecyl)phosphate (HDoP) anions, as asymmetric double-chain surfactants, were studied using X-ray diffraction and Raman scattering techniques. The results indicated a marked difference in the aggregate behavior between BDoP and HDoP, attributed to the difference in the extent of the steric effect of the two short chains. The Raman scattering spectra provided direct evidence of the steric effect. This marked difference in the steric effect is clearly reflected in the phase structures of the BDoP and HDoP water binary systems. [ABSTRACT FROM AUTHOR]

Patterns of glucocorticoid (GC) hormone regulation exhibit considerable inter-individual variation that is often examined relative to individual traits and fitness measures. Although stress-induced GC concentrations are repeatable within an individual in captive populations, this assumption remains untested in wild animals in their natural environment across longer time periods. We assessed the repeatability of baseline and post-stress GC concentrations in a wild teleost fish. Largemouth bass ( Micropterus salmoides) were captured and subjected to a standard stress protocol and then stocked into a small research lake. Upon recapture by angling up to 1 year later ( n = 26), fish were re-sampled following identical methods. After controlling for a strong effect of water temperature, we confirmed repeatability of post-stress cortisol concentrations despite stress presumed to accompany relocation. We documented no consistency in baseline GC concentrations. This study serves as an important validation for the use of post-stress cortisol concentrations as an individual trait. However, the effect size of repeatability was lower than that found in other taxa. Results also bring forth the reality that environmental variables such as temperature must be considered in studies where these factors can vary, such as when sampling wild animals at liberty. [ABSTRACT FROM AUTHOR]

Introduction: NCHDs are exposed to a great number of blood-borne infections. Needle stick injuries are possibly the main route of acquiring such infections from a non-consultant hospital doctors (NCHDs) perspective. This study examines NCHDs experiences surrounding needle stick injuries. Methods: A cross-sectional self-administered anonymous questionnaire survey was conducted on 185 NCHDs working in a clinical setting among seven teaching hospitals in Ireland. Implied consent was obtained. The data was analysed using Excel spreadsheets. Ethical approval was received. Results: A response rate of 85.4% (158/185) was achieved. Findings of the study are shown in the manuscript table. Conclusions: A needle stick injury (NI) history is greater among surgical NCHDs than medical NCHDs. The level of disposable glove usage is worryingly poor. Training in sharps handling and dealing with a NI needs to be addressed. HIV is the blood-borne infection most fear of being contracting as a consequence of a NI. [ABSTRACT FROM AUTHOR]

Background: Dementia patients in Ireland live 8 years on average after diagnosis and health policy aims to ensure patients are cared for in the home for as long as possible. Aim: To assess the role of general practitioners in Ireland caring for dementia carers. Methods: A PubMed search (1980-2010) was performed using MeSH terms 'caregivers or carers', 'Dementia or Alzheimer's disease', 'family physician or general practitioner'. An English language restriction was imposed and the search continued to June 24th 2010. Results: Psychosocial multidisciplinary interventions that unite education, skills training, management of psychological problems and family support in the community are effective in managing the problems of carers and should be facilitated by general practitioners. Conclusions: Dementia carers form an important yet understated patient group who present unique challenges for general practitioners in Ireland. [ABSTRACT FROM AUTHOR]

The extracellular fluid space is the site of intercellular communication and represents an important source of mediators that can shed light on the parenchymal environment. Sampling of this compartment using continuous microdialysis allows assessment of the temporal changes in extracellular mediators involved in tissue homeostasis and disease processes. However, novel biomarker identification is limited by the current need to utilize specific, targeted molecular assays. The aim of our study was to explore the use of qualitative and quantitative proteomic approaches to define the protein content of dermal dialysate. Timed dermal dialysate samples were collected from healthy human volunteers for 5 h following probe insertion, using a 3,000-kDa MWCO membrane perfused at a rate of 3 μl/min. Dialysate proteins were identified using GeLC-MS/MS and iTRAQ approaches and functions assigned according to the Gene Ontology classification system. More than 80 proteins (size range 11-516 kDa) originating from both extracellular and intracellular fluid space were identified using the qualitative approach of GeLC-MS/MS. Quantitative iTRAQ data were obtained for 27 proteins with relative change ratios between consecutive timed samples showing changes of >1.5-fold. Interstitial proteins can be identified and measured using shotgun proteomic techniques and changes detected during the acute inflammatory response. Our findings provide a platform from which to explore novel protein biomarkers and their modulation in health and disease. [ABSTRACT FROM AUTHOR]

Emiliania huxleyi is a unicellular marine phytoplankton species known to play a significant role in global biogeochemistry. Through the dual roles of photosynthesis and production of calcium carbonate (calcification), carbon is transferred from the atmosphere to ocean sediments. Almost nothing is known about the molecular mechanisms that control calcification, a process that is tightly regulated within the cell. To initiate proteomic studies on this important and phylogenetically remote organism, we have devised efficient protein extraction protocols and developed a bioinformatics pipeline that allows the statistically robust assignment of proteins from MS/MS data using preexisting EST sequences. The bioinformatics tool, termed BUDAPEST (Bioinformatics Utility for Data Analysis of Proteomics using ESTs), is fully automated and was used to search against data generated from three strains. BUDAPEST increased the number of identifications over standard protein database searches from 37 to 99 proteins when data were amalgamated. Proteins involved in diverse cellular processes were uncovered. For example, experimental evidence was obtained for a novel type I polyketide synthase and for various photosystem components. The proteomic and bioinformatic approaches developed in this study are of wider applicability, particularly to the oceanographic community where genomic sequence data for species of interest are currently scarce. [ABSTRACT FROM AUTHOR]

Polypropylene (PP) is typically solid phase thermoformed at temperatures close to its crystalline melting point, usually in the 150° to 160° Celsius range. In such conditions the mechanical properties of the material rapidly decline with temperature and these large changes in properties make Polypropylene one of the more difficult materials to process by thermoforming. This paper presents the findings of a study into the thermoforming behaviour of an industrial thermoforming grade of Polypropylene. Practical tests were performed using custom built thermoforming equipment at Queen’s University Belfast. Numerical simulations of these processes were similarly constructed to replicate thermoforming processes using industry standard Finite Element Analysis software. [ABSTRACT FROM AUTHOR]

Endotracheal tubes (ETTs) are used to establish airway access in patients with ventilatory failure and during general anaesthesia. Tube malpositioning can compromise respiratory function and can be associated with increased morbidity and mortality. Clinical assessment of ETT position normally involves chest auscultation, which is highly skill-dependent and can be misleading. The objective of this pilot study was to investigate breath sound changes associated with ETT malpositioning. Breath sounds were acquired in six human subjects over each hemithorax and over the epigastrium for tracheal, bronchial and oesophageal intubations. When the ETT was in the oesophagus, the acoustic energy ratio between epigastrium and chest surface increased in all subjects (p < 0.04). In addition, ETT placement in the right mainstem bronchus decreased the acoustic energy ratio between the left and right hemithoraxes in all subjects (p < 0.04). A baseline measurement of this energy ratio was needed for bronchial intubation identification. However, using this ratio after bandpass filtering (200-500 Hz) did not require a baseline value, which would increase the utility of this method for initial ETT placement. These results suggest that computerised analysis of breath sounds may be useful for assessment of ETT positioning. More studies are needed to test the feasibility of this approach further. [ABSTRACT FROM AUTHOR]

In addition to well-documented negative effects (e.g., environmental degradation and ethnic conflict) Indonesia's central government programs of transmigration and industrial forest management subvert indigenous rights (even if unintentionally) through appropriation of forested land and migrant subsidies. Although central control can be an effective strategy for resource management, Indonesia's programs have undercut their own objectives and may interact synergistically to increase population pressure, reduce available land, and intensify land use conflicts on the outer islands. Empirical data are needed to evaluate the interactions between transmigration and forest conversion and to design appropriate management strategies that incorporate local as well as central controls. [ABSTRACT FROM AUTHOR]

The use of a combination of electrokinetic remediation and phytoremediation to decontaminate two metal-polluted soils has been demonstrated in laboratory-scale reactors. One soil was heavily contaminated with copper, the other with cadmium and arsenic (2500 μg g-1 Cu; 300–400 μg g-1 Cd and 230 μg g-1 As, respectively). Test reactors with two separated chambers, each with a capacity of 5.25 kg soil, were constructed, then the respective chambers were filled with either a mixture of the polluted soil and a control topsoil (75:25) or topsoil alone. Reactors were sown with perennial ryegrass (Lolium perenne cv Elka) and a constant voltage of 30 V was applied continually across the soils in each reactor. Soil sampling took place at the start and the end of the test run, whilst plant foliage was sampled after approximately 3 weeks (both reactors) 6 weeks (Cd soil reactor only) and at the conclusion of each test run (98 days Cu soil, 80 days Cd soil). Soil and plant metal concentrations were measured, together with soil pH. Results showed that in both soils there was a significant re-distribution of metals from anode to cathode in the test reactors, coupled with an enhancement of plant Cu uptake in the cathode region for the Cu soil. Patterns of plant Cd uptake were less clear cut and were not as clearly related to the redistribution of Cd measured in the soil. There was significant acidification of soil at the anode in each test reactor, but soil pH in other parts of the reactor changed little during the course of the experiment. Plant growth was affected at the anode, but was not affected in other parts of the reactor. There was no visual evidence of metal toxicity in the ryegrass in either polluted soil. Some effects on soil fungi were apparent, with a stimulation of Fusarium infection of ryegrass in the cathode region of all reactors and the appearance of sporophores of Coprinus in the same location. It is concluded that the combination of the two techniques represents a very promising approach to the decontamination of metal polluted soils that now requires validation in field conditions. [ABSTRACT FROM AUTHOR]

Silica gel samples, modified with 3-mercaptopropyltriethoxysilane, and their S–S-bridged samples have been prepared. In order to characterize the microstructure of the surface of these silica gel samples, Raman scattering and diffuse reflectance Fourier transform IR spectra of these samples have been examined by comparison with Raman spectra of various n-alkyl disulfides and their related silane polymers. The S–S and C–S stretch modes characteristic of the CH2SSCH2 segment, in addition to the SH and C–S stretch modes of the CH2SH segment, have been assigned for these silica gel samples. It has been found that, even on the surface of the silica gel, a specific conformer is stabilized about the CH2SSCH2 segment. [ABSTRACT FROM AUTHOR]

A series of N-acetyl- L-glutamic acid oligopeptide benzyl esters with exact residue numbers 4, 6, and 12 has been synthesized by a stepwise procedure. For these oligopeptide–dioxane binary systems, the behavior of the liquid-crystalline phases has been examined␣by the use of 2H NMR, and the results indicate that highly ordered aggregates formed by these oligopeptides in dioxane are in an alignment similar to that in a nematic mesophase. [ABSTRACT FROM AUTHOR]

Structures of the micelles which are formed by the chiral oligopeptide surfactant N-dodecanoyl- L-proline tripeptide anions have been examined using small-angle neutron scattering spectral analysis. Results show that the chiral N-dodecanoyl- L-proline trimeric anions may form a spherical micelle with an aggregation number of 36 and that the oligopeptide portions with a poly- L-proline I-type helical structure are saturated with water. [ABSTRACT FROM AUTHOR]

The polymerization behavior of 3-aminopropyltriethoxysilane, a process initiated by water molecules, has been examined using time-resolved near-IR and 2D near-IR correlation spectra. By deconvolution of the time-resolved near-IR spectra, the existence of the component bands at 5189, 5265 and 5300 cm−1, whose intensities decrease markedly as the reaction proceeds, has been confirmed in the 5000–5400 cm−1 region. The band at 5189 cm−1 has been assigned to water molecules, while those at 5265 and 5300 cm−1 have been assigned to the strongly and weakly associated silanol groups, respectively. The kinetics of the hydrolysis of the ethoxy groups and of the formation of a siloxane bond have been analyzed using the time-dependent integral intensities of these three bands and the mechanisms of the reactions have been discussed. Evidence for this polymerization process is also clearly evident in the 2D near-IR correlation spectra. [ABSTRACT FROM AUTHOR]

The polymerization behavior of perfluorooctyltrimethoxysilane (PFOS) in ethanol, which is acid-catalyzed by 0.25 M HCl, has been examined using time-resolved near-IR and 2D near-IR correlation spectra. In the time-resolved near-IR spectra, the bands at 5164 and 4825 cm−1 have been assigned to the combination bands of water and ethanol OH groups, respectively. It has been found that the absorbance variation of the two near-IR bands occurs in a two-step process. The absorbance of the 5164 cm−1 band rapidly decreases in the initial step but increases exponentially in the second step, while that of the 4825 cm−1 band rapidly increases both in the initial step and, exponentially, in the second step. These results indicate that the time-dependent absorbance variation of the two near-IR bands reflects the polymerization process of PFOS, in which consumption and release of water molecules and release of methanol in the two-step process occur as a consequence of the acid-catalyzed hydrolysis of methoxy groups and the formation of silanols (SiOH) to form a siloxane bond. It has also been found that this polymerization process is distinctly reflected in the 2D near-IR correlation spectra. [ABSTRACT FROM AUTHOR]

The acid-catalyzed condensation reaction of perfluorooctyltrimethoxysilane (PFOS) and n-octyltrimethoxysilane (OTMS) in ethanol has been followed by time-resolved synchrotron radiation small-angle X-ray scattering (SAXS) on a short time scale. SAXS curves for PFOS and OTMS have been interpreted as arising from mass fractals with Df=2 (PFOS) and Df=1.7 (OTMS). The time dependence of the apparent radius of gyration, obtained from the Guinier plots, showed that the growth of fractal precursors occurs in a two-step process within 2 h for PFOS and within 1.5 h for OTMS, in which small clusters involving monomers, dimers and trimers are formed in the initial step and formation of larger clusters occurs in the second step. Furthermore, it has been suggested that the hydrophobicity and lipophobicity of the bulky alkyl groups may also contribute to the formation of these giant aggregates. [ABSTRACT FROM AUTHOR]

A homologous series of sodium dialkylsulfosuccinates, which are straight-chain analogues of Aerosol-OT with various chain lengths (dimethyl, diethyl, dibutyl, dihexyl, diheptyl, dioctyl, didecyl, diundecyl and didodecyl), has been synthesized. In order to assign the IR bands of the CH2 scissoring and CH deformation modes of the succinate segment, sodium dideuteratedmethylsulfosuccinate and sodium dideuteratedethylsulfosuccinate have also been synthesized. IR absorption spectra have been recorded for these mono-, di- and multihydrate samples in the solid state. In particular, IR bands in the 1250–1500 cm−1 region have been compared for sodium dimethylsulfosuccinate, sodium diethylsulfosuccinate and sodium diheptylsulfosuccinate, whose crystal structures are known. The CH2 scissoring and CH deformation modes of the succinate CH2-CH portion strongly depend upon the environment of hydration and on the length of the hydrocarbon portions. [ABSTRACT FROM AUTHOR]

A homologous series of sodium dialkylsulfosuccinates (SDAS) has been synthesized with various chain lengths (dibutyl, dihexyl, diheptyl, dioctyl, dinonyl, didecyl, diundecyl and didodecyl). These compounds are straight-chain analogues for Aerosol-OT. Raman scattering spectra have been recordered for these SDAS compounds, both in the solid state and in aqueous solutions. These spectra are analyzed in detail in the CH stretch and CH2 deformation regions, and the results depend specifically on the length of the hydrocarbon chain. In particular, the longitudinal accordion-like vibrational modes coming from the all-trans n-alkyl chains have been investigated. For the SDAS dihydrates, all hydrocarbon chains take up an extended form, whereas for the monohydrates the tails tend to become disordered at the CH2-CH2 single bond close to the terminal methyl groups. It has also been confirmed that for the concentrated aqueous SDAS (sodium dibutylsulfosuccinate – sodium dioctylsulfosuccinate) samples preferential stabilization of the extended conformation of the hydrocarbon chain may occur. [ABSTRACT FROM AUTHOR]

The dimeric bis(quaternaryammonium bromide) surfactants, [Br−(CH3)2N+(C mH2 m +1—(C2) s—(C mH2 m +1, s = 2, 3 and m = 4, 6, 10 and 12, s = 6 and m = 8, 10, 12], have been synthesized and the phase maps of the sm6-8-water, sm6-10-water and sm6-12-water binary systems have been determined (sm6-8 implies s = 6, m = 8). In order to examine the molecular structures of these solid samples and of their dimeric surfactant-water binary systems, Raman spectra of the simple dimeric surfactants, sm2-4 and sm3-4, in which crystal structures of the trans- and cis-type conformations have been determined by single-crystal X-ray diffraction analysis, have been investigated, and Raman bands characteristic of these skeletal structures were found in the skeletal deformation region. On the basis of these characteristic Raman bands for the two conformations, it has been concluded that the dimeric surfactants, sm6-8, sm6-10 and sm6-12 also take up a cis-type conformation in the crystalline state. Furthermore, it has been found that the Raman bands in the C—H stretching, skeletal stretching and CH+(CH3)2Br−, s = 2, 3 and m = 4, 6, 10 and 12, s = 6 and m = 8, 10, 12], have been synthesized and the phase maps of the sm6-8-water, sm6-10-water and sm6-12-water binary systems have been determined (sm6-8 implies s = 6, m = 8). In order to examine the molecular structures of these solid samples and of their dimeric surfactant-water binary systems, Raman spectra of the simple dimeric surfactants, sm2-4 and sm3-4, in which crystal structures of the trans- and cis-type conformations have been determined by single-crystal X-ray diffraction analysis, have been investigated, and Raman bands characteristic of these skeletal structures were found in the skeletal deformation region. On the basis of these characteristic Raman bands for the two conformations, it has been concluded that the dimeric surfactants, sm6-8, sm6-10 and sm6-12 also take up a cis-type conformation in the crystalline state. Furthermore, it has been found that the Raman bands in the C—H stretching, skeletal stretching and CH2 scissoring regions are sensitive to phase structure. [ABSTRACT FROM AUTHOR]

The microstructure of the micelles formed in aqueous solution by gemini surfactants with aromatic spacers, [Br(CH3)2N+(C mH2)-(Ph)-(C m +1)-(Ph)-(C mH2 m +1)N+(CH3)2Br, m=8 and Ph = o-, m- or p-phenylenedimethylene] has been examined by small-angle neutron scattering. Aggregation of the gemini surfactants with an o-phenylenedimethylene spacer brings about formation of premicelles and small micelles at concentrations below the second critical micelle concentration, while above this concentration marked micellar growth and variation in shape occurs. It is suggested that the minimum aggregate formed at this critical micelle concentration may be the trimer or tetramer and that this result supports the mechanism of “gemini → submicelle → assembly” for micellar growth. [ABSTRACT FROM AUTHOR]

The microstructure of the normal micelles formed by dimeric surfactants with long spacers, [Br−(CH3)2N+(C mH2 m +1 -(C2) S -(C mH2 m +1)N+(CH3)2Br−, m = 10 and s = 8, 10 and 12], has been investigated by small-angle neutron scattering and compared with previously reported results for micelles of the same dimeric surfactants with shorter spacers ( m = 10 and s = 2, 3, 4 and 6). It was found that for dimeric surfactants with long spacers ( s = 8 and 10), both micellar growth and variation in shape occur to only a small extent, if at all, compared with dimeric surfactants with short spacers. However, for the dimeric surfactant with the longest spacer, s = 12, the extent of micellar growth and shape variation is also large. These results are due to the differences in conformation of dimeric surfactants with short spacers ( s = 2–6) compared with that of the surfactants with long spacers ( s = 8–12). [ABSTRACT FROM AUTHOR]

The Australian brushtail possum ( Trichosurus vulpecula) is the major vertebrate pest in New Zealand. Possums cause significant damage to the country's native and exotic forests and, as a vector of bovine tuberculosis, are a serious threat to the country's meat industry. Strong smelling odors are often used as lures during possum control operations in New Zealand, but little is known about the preferences of possums for these odurs. A test was designed to determine the preferences of captive wild possums for a number of odors commonly used as lures. To assess the effectiveness of the method, the possums were tested for their responses to a familiar food odor (apple) versus no odor. The possums spent significantly more time investigating the apple odor and also sniffed it more often than the no-odor control in the 15-min test period. The same procedure, however, showed that five odors commonly used as lures (almond, cloves, cinnamon, peanut, and orange) were no more preferable than water. Our results suggest that these unfamiliar odors are either equally attractive or unattractive to possums and that odors that are more familiar to these animals may be more appropriate as lures. [ABSTRACT FROM AUTHOR]

A simple method to encapsulate intramicellar solutes (enzymes, nanoparticles) in polymer microspheres is described. The method involves dissolving a polymer in a minimum amount of solvent. The polymer solution is then added to a large volume of a nonsolvent system containing bis(2-ethylhexyl)sulfosuccinate (AOT) reversed micelles. Immediate precipitation of the dissolved polymer takes place. The precipitation results in the formation of stable microparticles ∼0.1–1 µm in diameter. There is a direct correlation between the internal voidage of the particles and the water content of the micelles. Precipitation also leads to encapsulation of intramicellar solutes, resulting in the formation of microspherical composites. [ABSTRACT FROM AUTHOR]

Three silica gel sample systems, modified with 3-aminopropyltriethoxy silane (APTS), were prepared by sequentially sampling the reaction mixture at various time intervals. The concentrations of 3-aminopropylsilyl groups (APS) bound on the silica surface were determined by elemental analysis. For the same sample systems, 29Si NMR intensities of an (-O)4Si species belonging only to the silica gel particles and corrected by a cross-polarization correction factor were also measured. Both the APS-concentrations and the corrected 29Si NMR intensities depended upon reaction time, reflecting the rate of the APTS-silica gel reaction. Kinetic analysis of these data was made by use of the Gauss-Newton method, and the overall reaction was found to consist of three reaction processes (an initial fast reaction, a slower second reaction and a much slower third reaction). In particular, the conversion of (-O)3SiOH to (-O)4Si is predominant in the second reaction process and the pore size of a silica gel particle affects the reaction mechanism. [ABSTRACT FROM AUTHOR]

Changes in the 13C and 1H NMR chemical shifts of the silane coupling agent (3-aminopropyltri-ethoxysilane, APTS) in toluene, which were detected as the concentration of APTS increased, have been interpreted in terms of the formation of micelles and the presence of a critical micelle concentration (CMC) equal to ca. 0.47 mol 1 -1. For the protons of the n-propyl segment, 1H NMR splitting patterns have been analyzed and conformations of the propyl segment have been discussed. Plots of relative absorbance of the two NH2 stretch IR bands at 3324 and 3384 cm -1 against concentration provided an inflection point (corresponding to the CMC) at a value equal to 0.46 mol 1 -1 Thus, consideration of the interaction of APTS with a surface must take into account the presence of both APTS aggregates as well as APTS monomers. [ABSTRACT FROM AUTHOR]

One of the life threatening complications of diabetes is hypoglycaemia. It is a common complication, with times of greatest risk being before meals and during the night. Symptoms usually develop when the blood glucose level falls below 3.5 mmol/l. Many patients with long-standing diabetes report loss of warning symptoms. Prevention of such hypoglycaemic attacks is highly desirable. Recently a dog’s ability to detect hypoglycaemia in diabetic patients has been recorded. This is the first recorded case of hypoglycaemia in a non-diabetic patient being detected by a dog and also we believe it to be the first report of hypoglycaemia being detected by a dog in this country (Ireland). [ABSTRACT FROM AUTHOR]

Evaluates a novel arc-electrodeposition technique for preparing shape controlled metal nanorods, nanorods or metal-oxide nanotubes. Overview of the process of arc-electrodeposition involving exothermic heat; Experiment set-up and procedure preparation of the cadmium compound nanotube; Collection of the final product through centrifugation; Identification of the product using an x-ray diffractometer; Exhibition of a tubular structure of the cadmium nanoparticle; Impact of the aqueous electrolyte solution on the nucleation and growth process of the nanoparticle clusters.