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Increasing demands for better instrumental methods to evaluate cooked rice texture is driving innovations in rice texture research. This study characterized cooked rice texture by descriptive sensory analysis and two instrumental methods (texture profile analysis (TPA) and dynamic rheological testing) using a set of 18 varieties of rice with a wide range in amylose content (0-30%). The panellists' results indicated that hardness and stickiness were the two most discriminating attributes among 13 tested textural attributes. The consistency coefficient (K(*)) and loss tangent (tan δ) from a dynamic frequency sweep were used to compare with hardness and stickiness tested by TPA and sensory panellists, showing that using K(*) to express hardness, and tan δ to express stickiness, are both statistically and mechanistically meaningful. The instrumental method is rationalized in terms of starch structural differences between rices: a higher proportion of both amylose and long amylopectin branches with DP 70-100 causes a more elastic and less viscous texture, which is readily understood in terms of polymer dynamics in solution., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Purpose: In 2007, Australia published standardized terminology and definitions for three levels of thickened fluids used in the management of dysphagia. This study examined the thickness of the current Australian National Fluid Standards rheologically (i.e. viscosity, yield stress) and correlated these results with the "fork test", as described in the national standards., Method: Clinicians who prescribe or work with thickened liquids and laypersons were recruited to categorize 15 different thickened fluids of known viscosities using the fork test. The mean apparent viscosity and the yield stress for each fluid category were calculated., Result: Clear responses were obtained by both clinicians and laypersons for very thin fluids (< 90 mPa.s) and very thick fluids (> 1150 mPa.s), but large variations of responses were seen for intermediate viscosities. Measures of viscosity and yield stress were important in allocating liquids to different categories., Conclusion: Three bands of fluid viscosity with distinct intermediate band gaps and associated yield stress measures were clearly identifiable and are proposed as objective complements to the Australian National Standards. The "fork test" provides rudimentary information about both viscosity and yield stress, but is an inexact measure of both variables.

Statistically and causally meaningful relationships are established between starch molecular structure (the molecular distribution of branched starch and the chain length distribution of debranched starch) and texture (hardness and stickiness) of cooked rice grains. The amounts of amylose chains with degree of polymerization (DP) 100-20,000, and of long amylopectin chains, positively correlated with hardness, while amylopectin chains with DP<70 and amylose molecular size both showed negative correlations with hardness (p<0.05). There was also a significant negative correlation between stickiness and the amounts of long amylopectin chains (p<0.01). For rices with similar amylose content, the amount of amylose chains with DP 1000-2000 positively correlated with hardness while size negatively correlated with hardness (p<0.05). This indicates for the first time that, regardless of amylose content, rice varieties with smaller amylose molecular sizes and with higher proportions of long amylose chains have a harder texture after cooking., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Meprobamate, a benzodiazepine-like drug, was commonly prescribed for anxiety in the 1960s and 1970s, but fell out of favour, at least in part, due to the risk of dependence, for which there is little published evidence to guide clinical management. We discuss a 70-year-old man with a 45-year history of meprobamate dependency and multiple failed previous withdrawal attempts who was successfully withdrawn from meprobamate using diazepam during a 2-week inpatient stay on a specialist Addictions ward. An appropriate diazepam dose was established using the Clinical Institute Withdrawal Assessment scale for benzodiazepines (CIWA-B). This dose was then slowly reduced over 12 days. Multidisciplinary input, especially psychological therapy tackling his underlying anxiety disorder during his admission, was thought to be particularly helpful., (2016 BMJ Publishing Group Ltd.)

Objective The current standard used to measure setting time for Mineral Trioxide Aggregate (MTA) involves indentation testing with arbitrary weights. This study compared indentation testing against rheological measurements and assessed the influences of particle size and the inclusion of bismuth oxide on the setting time of experimental MTA and Portland cement (PC). Material and methods Two PCs (P1 and P2) of different particle sizes were produced using the same clinker. From these two PCs, two experimental MTAs (M1 and M2) were created with the addition of bismuth oxide. Particle size distributions were assessed using laser diffraction analysis. Indentation setting time tests were performed in accordance to the Gillmore needle test. Elastic modulus was assessed using a strain-controlled rheometer at 1 rad s -1 and an applied strain of 0.01%. Results P1, P2, M1 and M2 cements had median particle sizes of 6.1, 12.5, 6.5 and 13.0 μm, respectively. Using indentation testing, final setting times were ranked P1 < M1 < P2 < M2. The ranking of the final setting time corresponded with the rheological assessment of time required to reach 95% of the elastic modulus plateau. Conclusions The time to reach 95% elastic modulus plateau of 9.3 min corresponds to a time close to the point where the material can be overlaid with another restorative material to give a final restoration. The 95% plateau value for elastic modulus may be a more useful parameter for determining how the setting reaction of PC and MTA cements progress over time., Competing Interests: This study was supported by the Australian Dental Research Foundation (Grant 2011001653).

Background: Urethral strictures can be difficult to diagnose at an early stage because the urinary flow rate does not diminish until the urethral calibre is ≤3mm. In the past, posturethral surgery follow-up has relied upon flow rates and contrast imaging., Objective: To evaluate the role of flexible urethroscopy in the follow-up of patients undergoing urethroplasty., Design, Setting, and Participants: Prospective flexible urethroscopy follow-up of 144 male patients who underwent urethroplasty by a single surgeon over a 10-yr period at a tertiary referral centre., Intervention: Flexible urethroscopy at 3, 6, and 12 mo postoperatively, and annually thereafter., Outcome Measurements and Statistical Analysis: Type of recurrence, based on urethroscopy findings, and further interventions were measured. Actuarial analysis was performed using Kaplan-Meier curves and a log-rank test., Results and Limitations: All 144 patients underwent flexible urethroscopy follow-up over a median postoperative follow-up of 22 mo (range: 1-96 mo). No further intervention was required for 117 patients (81.25%); 27 (18.75%) developed recurrences that required further treatment. Recurrences included diaphragms (13 patients) or significant restenosis (14 patients). Diaphragms were treated by urethrotomy, gentle dilatation, or a short course of intermittent self-dilatation. Restenosis required repeated simple procedures or surgical revision. Most recurrences (26 of 27, 96%) were detected within the first year. Urinary peak flow-rate data were available for 11 of 27 of these recurrences; 7 patients had flow rates >15ml/s. Anastomotic procedures had greater success than augmentation urethroplasty (p=0.0136); there was no significant difference in outcomes between redo and non-redo surgery (p=0.2093) CONCLUSIONS: Endoscopic follow-up of patients after urethroplasty enables earlier identification and treatment of recurrences compared to the use of urinary flow rates alone. It also enables the identification of two different morphologic recurrence patterns that require different types of intervention., Patient Summary: Endoscopy detects most stricture recurrences within 1 yr after urethroplasty and is more sensitive than using urinary flow rates alone., (Copyright © 2015. Published by Elsevier B.V.)

Objectives: To evaluate the neural correlates of implicit processing of negative emotions in motor conversion disorder (CD) patients., Methods: An event related fMRI task was completed by 12 motor CD patients and 14 matched healthy controls using standardised stimuli of faces with fearful and sad emotional expressions in comparison to faces with neutral expressions. Temporal changes in the sensitivity to stimuli were also modelled and tested in the two groups., Results: We found increased amygdala activation to negative emotions in CD compared to healthy controls in region of interest analyses, which persisted over time consistent with previous findings using emotional paradigms. Furthermore during whole brain analyses we found significantly increased activation in CD patients in areas involved in the 'freeze response' to fear (periaqueductal grey matter), and areas involved in self-awareness and motor control (cingulate gyrus and supplementary motor area)., Conclusions: In contrast to healthy controls, CD patients exhibited increased response amplitude to fearful stimuli over time, suggesting abnormal emotional regulation (failure of habituation / sensitization). Patients with CD also activated midbrain and frontal structures that could reflect an abnormal behavioral-motor response to negative including threatening stimuli. This suggests a mechanism linking emotions to motor dysfunction in CD.

Despite the rhizotoxicity of aluminum (Al) being identified over 100 years ago, there is still no consensus regarding the mechanisms whereby root elongation rate is initially reduced in the approximately 40% of arable soils worldwide that are acidic. We used high-resolution kinematic analyses, molecular biology, rheology, and advanced imaging techniques to examine soybean (Glycine max) roots exposed to Al. Using this multidisciplinary approach, we have conclusively shown that the primary lesion of Al is apoplastic. In particular, it was found that 75 µm Al reduced root growth after only 5 min (or 30 min at 30 µm Al), with Al being toxic by binding to the walls of outer cells, which directly inhibited their loosening in the elongation zone. An alteration in the biosynthesis and distribution of ethylene and auxin was a second, slower effect, causing both a transient decrease in the rate of cell elongation after 1.5 h but also a longer term gradual reduction in the length of the elongation zone. These findings show the importance of focusing on traits related to cell wall composition as well as mechanisms involved in wall loosening to overcome the deleterious effects of soluble Al., (© 2015 American Society of Plant Biologists. All Rights Reserved.)

Conversion disorder (CD) is a condition where neurological symptoms, such as weakness or sensory disturbance, are unexplained by neurological disease and are presumed to be of psychological origin. Contemporary theories of the disorder generally propose dysfunctional frontal control of the motor or sensory systems. Classical (Freudian) psychodynamic theory holds that the memory of stressful life events is repressed. Little is known about the frontal (executive) function of these patients, or indeed their general neuropsychological profile, and psychodynamic theories have been largely untested. This study aimed to investigate neuropsychological functioning in patients with CD, focusing on executive and memory function. A directed forgetting task (DFT) using words with variable emotional valence was also used to investigate memory suppression. 21 patients and 36 healthy controls completed a battery of neuropsychological tests and patients had deficits in executive function and auditory-verbal (but not autobiographical) memory. The executive deficits were largely driven by differences in IQ, anxiety and mood between the groups. A subgroup of 11 patients and 28 controls completed the DFT and whilst patients recalled fewer words overall than controls, there were no significant effects of directed forgetting or valence. This study provides some limited support for deficits in executive, and to a lesser degree, memory function in patients with CD, but did not find evidence of altered memory suppression to support the psychodynamic theory of repression., (© 2013 The British Psychological Society.)

When a dysphagic infant is prescribed thickened infant formula (TIF) as a treatment method, some clinicians determine their own addition rates of thickener to meet the specific needs of the infant rather than relying on the directions on the tin. In this study the rheological behaviour of a TIF at different addition levels of thickener was measured to determine whether there was a difference in full rheological response and in viscosity. In addition, the time taken for the TIF to reach a near-stable viscosity was also measured. One hundred grams of Karicare® infant formula was made up according to the manufacturer’s instructions and Karicare® feed thickener was added at levels of 2, 3, 4, 5, and 6 g, respectively. A strain-controlled rheometer (ARES) with Couette geometry was used to rheologically characterise the TIF at the different levels of thickener addition. There was a significant difference in viscosity between the low levels and the higher levels of addition thickener (p < 0.05). Also, the low levels of thickener addition showed Newtonian-like behaviour, whereas the higher levels of addition were shear-thinning. The time taken for the thickener to reach a near-stable viscosity was found to be 10 min. Guidelines for thickened infant formula need to take into account the different levels of thickener addition rates.

Functional (conversion) neurological symptoms (FNS) are commonly encountered in neurological and psychiatric clinical settings and represent a considerable burden on healthcare systems. There is a conspicuous paucity of evidence-based treatments for FNS. Transcranial magnetic stimulation (TMS) offers a safe, non-invasive method of probing changes in cortical excitability and/or connectivity. It has already had some success in demonstrating abnormalities of cortical excitability in patients with FNS, particularly when the functional symptom in question relates to movement. We reviewed the literature for studies in which TMS has been used in the treatment of FNS. All patients in the identified studies had motor symptoms (either weakness or movement disorder). There was considerable heterogeneity in terms of study quality, population sampled, study design, TMS parameters and outcome measures. No studies were placebo controlled. Despite the majority of studies claiming success for the technique, there is insufficient good quality evidence to establish TMS as an effective treatment modality for FNS. We outline the methodological considerations that should be taken into account in future studies of the efficacy of TMS in treating FNS and discuss mechanisms by which TMS, if efficacious, may exert a therapeutic effect, including: (a) via genuine neuromodulation, (b) via non-specific placebo effects and (c) by demonstrating, through its immediate effects on the motor system (eg, movement in a 'paretic' limb), that symptom improvement is possible, thus directly changing higher level beliefs that may be responsible for the maintenance of the disorder.

Objective: To detect anatomical differences in areas related to motor processing between patients with motor conversion disorder (CD) and controls., Methods: T1-weighted 3T brain MRI data of 15 patients suffering from motor CD (nine with hemiparesis and six with paraparesis) and 25 age- and gender-matched healthy volunteers were compared using voxel-based morphometry (VBM) and voxel-based cortical thickness (VBCT) analysis., Results: We report significant cortical thickness (VBCT) increases in the bilateral premotor cortex of hemiparetic patients relative to controls and a trend towards increased grey matter volume (VBM) in the same region. Regression analyses showed a non-significant positive correlation between cortical thickness changes and symptom severity as well as illness duration in CD patients., Conclusions: Cortical thickness increases in premotor cortical areas of patients with hemiparetic CD provide evidence for altered brain structure in a condition with presumed normal brain anatomy. These may either represent premorbid vulnerability or a plasticity phenomenon related to the disease with the trends towards correlations with clinical variables supporting the latter.

Importance: Freud argued that in conversion disorder (CD) the affect attached to stressful memories is "repressed" and "converted" into physical symptoms, although this has never been subject to scientific study to our knowledge., Objective: To examine the neural correlates of recall of life events judged to be of causal significance in CD., Design, Setting, and Participants: Case-control study. Academic research setting among 12 patients with motor CD and 13 healthy control subjects., Main Outcomes and Measures: Stressful life events were assessed using the Life Events and Difficulties Schedule and rated by a blinded panel for their likelihood to cause CD based on the threat posed and the extent to which subsequent illness might allow escape from some of their consequences (termed escape). Recall of those events (escape condition) was compared with recall of equally threatening control events from the same epoch (severe condition) in a functional magnetic resonance imaging task., Results: Relative to controls, patients showed significantly increased left dorsolateral prefrontal cortex and decreased left hippocampus activity during the escape vs severe condition, accompanied by increased right supplementary motor area and temporoparietal junction activity. Relative to controls, patients failed to activate the right inferior frontal cortex during both conditions, and connectivity between amygdala and motor areas (supplementary motor area and cerebellum) was enhanced., Conclusions and Relevance: These data offer support for the notion that the way adverse events are processed cognitively can be associated with physical symptoms in CD. Abnormal emotion (dorsolateral prefrontal cortex and right inferior frontal cortex) and memory control (hippocampus) are associated with alterations in symptom-related motor planning and body schema (supplementary motor area and temporoparietal junction).

This work revealed that the interactions between starch, the ionic liquid 1-ethyl-3-methylimidazolium acetate ([Emim][OAc]), and water might contribute to the phase transition (gelatinization, dissolution, or both) of native starch at reduced temperature. Using mixtures of water and [Emim][OAc] at certain ratios (7.2/1 and 10.8/1 mol/mol), both the gelatinization and dissolution of the starch occur competitively, but also in a synergistic manner. At lower [Emim][OAc] concentration (water/[Emim][OAc] molar ratio≥25.0/1), mainly gelatinization occurs which is slightly impeded by the strong interaction between water and [Emim][OAc]; while at higher [Emim][OAc] concentration (water/[Emim][OAc] molar ratio≤2.8/1), the dissolution of starch is the major form of phase transition, possibly restricted by the difficulty of [Emim][OAc] to interact with starch., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The interactions of block copolymers with surfaces can be controlled by coating those surfaces with appropriate statistical copolymers. Usually, a statistical copolymer comprised of monomer units identical to those of the block copolymer is used; that is, typically a poly(styrene)-stat-poly(methyl methacrylate) (PS-stat-PMMA) is used to direct the alignment of poly(styrene)-block-poly(methyl methacrylate) (PS-block-PMMA), and poly(styrene)-stat-poly(2-vinylpyridine) (PS-stat-P2VP) has been used for poly(styrene)-block-poly(2-vinylpyridine) (PS-block-P2VP). Reports of controlling the orientation of block copolymers with statistical copolymers with a dissimilar composition are limited. Here, we demonstrate that this method can be further extended to show that PS-stat-PMMA can be used to control the wetting properties of poly(styrene)-block-poly(D,L-lactide) (PS-block-PDLA). Surfaces were modified with a series of cross-linked PS-stat-PMMA-stat-glycidyl methacrylate terpolymers, and the surface chemistries and energies were assessed using angle-dependent X-ray photoelectron spectroscopy and the two-liquid harmonic method, respectively. From these experiments, an expected neutral compositional window was identified for symmetrical PS-block-PDLA. Moreover, high-resolution SEM, AD-XPS, and grazing-incidence SAXS measurements were used to evaluate the morphology of PS-block-PDLA as a function of the surface composition of the underlying cross-linked copolymer films, and the neutral composition was found to range from 32 to 38 mol % of PS, in the bulk polymer. Ultimately, we demonstrated the determination of nonpreferential surface compositions that allow the self-assembly of lamellae with sizes in the sub-10 nm regime that are oriented perpendicular to the substrate. These findings have important implications for the use of PS-block-PDLA block copolymers in directed self-assembly, most specifically in advanced lithographic processes.

Purpose: Khat use has been suggested to be associated with psychosis, but its prevalence and associations among mental health service users have not been described in either traditional use countries or countries with immigrant populations from traditional use countries. We aimed to investigate the clinical and demographic associations of khat use in a sample of Somali users of mental health service users in South London., Methods: We used an electronic case register of 150,000 mental health patients to investigate the associations of khat use among all 240 Somali patients in the database. We used logistic regression to generate adjusted estimates for a range of exposure variables and used multiple imputation as a principled approach to missing data., Results: Khat use or non-use was recorded for 172 patients (72% of the total), of whom 80 (47%) were current users. Khat use was very strongly associated with ICD-10 primary diagnosis of schizophrenia, psychosis or drug and alcohol disorder (compared to ICD-10 F43 stress-related disorders and other non-psychotic disorders), male gender, harmful or dependent use of alcohol, and detention under the Mental Health Act., Conclusions: Recording and monitoring of khat use need to be more consistent in clinical settings, and further studies are required to investigate the much higher rates of use among those with psychotic disorders compared to non-psychotic disorders.

Functional neurological symptoms (FNS) are commonly encountered but have engendered remarkably little academic interest. 'UK-Functional Neurological Symptoms (UK-FNS)' was an informal inaugural meeting of UK based clinicians in March 2011 with a variety of research and clinical interests in the field. This narrative review reflects the content of the meeting, and our opinion of key findings in the field since the turn of the millennium.

Background: Symptoms of obsessive-compulsive disorder (OCD) have been described in neuropsychiatric syndromes associated with streptococcal infections. It is proposed that antibodies raised against streptococcal proteins cross-react with neuronal proteins (antigens) in the brain, particularly in the basal ganglia, which is a brain region implicated in OCD pathogenesis., Aims: To test the hypothesis that post-streptococcal autoimmunity, directed against neuronal antigens, may contribute to the pathogenesis of OCD in adults., Method: Ninety-six participants with OCD were tested for the presence of anti-streptolysin-O titres (ASOT) and the presence of anti-basal ganglia antibodies (ABGA) in a cross-sectional study. The ABGA were tested for with western blots using three recombinant antigens; aldolase C, enolase and pyruvate kinase. The findings were compared with those in a control group of individuals with depression (n = 33) and schizophrenia (n = 17)., Results: Positivity for ABGA was observed in 19/96 (19.8%) participants with OCD compared with 2/50 (4%) of controls (Fisher's exact test P = 0.012). The majority of positive OCD sera (13/19) had antibodies against the enolase antigen. No clinical variables were associated with ABGA positivity. Positivity for ASOT was not associated with ABGA positivity nor found at an increased incidence in participants with OCD compared with controls., Conclusions: These findings support the hypothesis that central nervous system autoimmunity may have an aetiological role in some adults with OCD. Further study is required to examine whether the antibodies concerned are pathogenic and whether exposure to streptococcal infection in vulnerable individuals is a risk factor for the development of OCD.

The diagnosis of conversion disorder is problematic. Since doctors have conceptually and practically differentiated the symptoms from neurological ('organic') disease it has been presumed to be a psychological disorder, but the psychological mechanism, and how this differs from feigning (conscious simulation), has remained elusive. Although misdiagnosis of neurological disease as conversion disorder is uncommon, it remains a concern for clinicians, particularly for psychiatrists who may be unaware of the positive ways in which neurologists can exclude organic disease. The diagnosis is anomalous in psychiatry in that current diagnostic systems require that feigning is excluded and that the symptoms can be explained psychologically. In practice, feigning is very difficult to either disprove or prove, and a psychological explanation cannot always be found. Studies of childhood and adult psychological precipitants have tended to support the relevance of stressful life events prior to symptom onset at the group level but they are not found in a substantial proportion of cases. These problems highlight serious theoretical and practical issues not just for the current diagnostic systems but for the concept of the disorder itself. Psychology, physiology and functional imaging techniques have been used in attempts to elucidate the neurobiology of conversion disorder and to differentiate it from feigning, but while intriguing results are emerging they can only be considered preliminary. Such work looks to a future that could refine our understanding of the disorder. However, until that time, the formal diagnostic requirement for associated psychological stressors and the exclusion of feigning are of limited clinical value. Simplified criteria are suggested which will also encourage cooperation between neurology and psychiatry in the management of these patients.

Infants experiencing dysphagia may undergo a videofluoroscopic swallow study (VFSS) to assess radiologically their coordination for sucking, swallowing, and breathing. No studies known to these authors have investigated whether the liquids used during infant radiological procedures are representative of liquids routinely fed to infants (e.g., formula). This study used an Advanced Rheometric Expansion System (ARES) strain-controlled rheometer to compare prethickened antiregurgitation formula, regular (thin) infant formula, and two types of regular infant formula, hand-thickened with a thickening agent and with liquid Polibar™ (barium-impregnated liquid). The viscosity, density, and yield stress of all samples were determined. Heated versus cooled liquids were compared. Results showed a significant difference in all rheological and material property parameters among the barium-impregnated liquids and the thickened and unthickened infant formula. This finding has important implications for the interpretation of the radiological results and subsequent clinical recommendations.

Rheology of Ca-pectate gels is widely studied, but the behaviour of pectate gels formed by Cu, Al and La is largely unknown. It is well known that gel strength increases with increasing Ca concentration, and it is hypothesised that this would also be the case for other cations. Pectins are a critical component of plant cell walls, imparting various physicochemical properties. Furthermore, the mechanism of metal toxicity in plants is hypothesised to be, in the short term, related to metal interactions with cell wall pectin. This study investigated the influence of Ca, Cu, Al and La ion concentrations at pH 4 on the storage modulus as a function of frequency for metal-pectin gels prepared from pectin (1%) with a degree of esterification of 30%. Gels were formed in situ over 6d in metal chloride solution adjusted daily to pH 4. Cation concentration was varied to develop a relationship between gel strength and cation concentration. At similar levels of cation saturation, gel strength increased in the order of La

The sol-gel transition of extracellular polymeric substances (EPS) derived from sludge flocs and granules is investigated in order to explain basic differences between the two aggregates. A reversible, pH dependent sol-gel transition was observed at pH 9.0-12.0 in EPS extracted from granules. At pH <9 granule EPS existed as a strong gel, indicating that their EPS exist in a gel state at normal operating pH of a wastewater treatment system (i.e. 6.0-8.5). This characteristic transition from solution to strong gel was not observed in any of the EPS samples derived from floccular sludges. A transition to a weak gel was however, observed at pH 4.0-5.0. Enriched exopolysaccharides from the granular EPS exhibited rheological behaviour analogous to the granules and the granule EPS. The critical overlap concentration (c*) of the exopolysaccharide concentrate was 0.33% w/w, similar to the c* of other known bacterial exopolysaccharides. Additionally, the protein content was found to be not contributing to the storage modulus of granule EPS gels. These factors suggest that exopolysaccharides or glycosides were the gelling agent in aerobic sludge granules. Given that EPS derived from aerobic sludge granules and flocs are distinguished by such a sol-strong gel transition, these exopolysaccharides therefore likely play an important role in granulation.

Delirium occurs in up to 50% of general hospital inpatients and is even more common in terminal illness. It is associated with a high morbidity and mortality, regularly missed and importantly is often either preventable or treatable.

Aerobic sludge granules are larger, denser microbial aggregates than activated sludge flocs with a smoother and more regular surface, which facilitates greater wastewater treatment intensity. Factors important in their growth are still poorly understood, which is an impediment to the construction and operation of full-scale aerobic sludge granule processes. Data in this article obtained with granules treating an abattoir wastewater provide evidence that aerobic sludge granules are hydrogels. The results also demonstrate a method for characterizing macromolecular associations. The rheological profile of these granules was found to be analogous with that of typical polymer gels. Water uptake or swelling reflects an equilibrium between granule elastic modulus and osmotic pressure, whereby uptake is increased by reducing solute concentration or the elastic modulus. A weakening of the extracellular polymeric substance (EPS) matrix as demonstrated with mechanical spectroscopy was induced by several environmental factors including temperature, pH and ionic strength. Uniform and elastic deformation was observed at low strain. Enzymatic degradation studies indicate that proteins and alpha-polysaccharides were the major granule structural materials. The aerobic sludge granules in the current study were therefore protein-polysaccharide composite physical hydrogels. While aerobic sludge granules treating an abattoir wastewater are used as a case study, many of the fundamental principles detailed here are relevant to other granulation processes. The paradigm established in this study can potentially be applied to better understand the formation of aerobic sludge granules and thus overcome a hurdle in the acceptance of aerobic sludge granulation as an alternative to more traditional wastewater treatment processes.

An elderly artist developed a transient paranoid psychosis when on a cultural tour of Florence, a city of particular emotional significance to him. He has since had several milder relapses that quickly settle.

Background: Negative symptoms in schizophrenia are associated with deficits in executive function and frequently prove highly resistant to neuroleptic medication. Using repetitive transcranial magnetic stimulation (rTMS) to activate the prefrontal cortex has been suggested as a treatment for negative symptoms., Methods: We performed a double-blind randomized controlled pilot study of real versus sham rTMS for negative symptoms in schizophrenia. 17 right-handed patients with prominent negative symptoms (PANSS negative subscore >or=20) were randomized to a 10 day course of real (n=8) or sham rTMS (n=9) applied to the left dorsolateral prefrontal cortex (20 trains per day, 10 s treatment at 10 Hz, 50 s inter-train interval, 110% of motor threshold). The primary outcome measure was PANSS negative symptom score. Secondary outcomes included mood, cognitive function and side-effects. Patients were followed-up two weeks afterwards. The main effect of treatment arm was evaluated across end of treatment and two-week follow-up time points using ANCOVA., Results: All subjects completed the treatment course. There was no significant difference between the two groups on PANSS negative symptom scores at either time point. At the end of treatment, no subjects in either group met the criterion for response (i.e. a 20% reduction in baseline PANSS negative symptom score). The real rTMS group had better delayed recall on a test of verbal learning than the sham group at 2 week follow-up., Conclusions: Real rTMS was not found to be better than sham rTMS in alleviating negative symptoms of schizophrenia although it was associated with some improvement in aspects of cognitive function at follow-up.

The effect of moisture content and temperature on water diffusion into a modified high amylose (< or = 90%) maize thermoplastic starch blend was investigated. Gravimetric and magnetic resonance imaging (MRI) studies were conducted to elucidate the diffusion mechanism and diffusion coefficients for this system. The diffusion coefficient data demonstrated that the rate of water diffusion into this blend was significantly dependent upon temperature and moisture content. Water diffusion was faster at higher temperatures and generally for samples stored at higher relative humidity environments. It was revealed from the gravimetric data that water diffusion into this starch blend was Fickian; however, further analysis of the MRI images found that the water diffusion mechanism was exponentially dependent on the concentration. This result was determined by comparing experimental water concentration profiles to a theoretical model calculated using the implicit Crank-Nicolson finite difference method.

We investigate the interaction of ethylene and ethane with a Cu-tricarboxylate complex and show that at low loadings the lighter molecule has a higher binding energy as a result of an increased interaction with the framework Cu and stronger hydrogen bonding with the basic framework oxygens. This leads to selective adsorption of ethylene by a factor of about 2 at low pressure, which is overcome by the stronger van der Waals interaction of ethane at high loadings, explaining recent literature data. The results suggest the possibility of separation of light hydrocarbons at low pressures or in trace amounts.

A case (based upon an association with cerebral asymmetry) has been presented for a gene for psychosis within the Xq21.3/Yp region of homology that is specific to Homo sapiens. We tested this hypothesis using the pentanucleotide marker DXYS 156 that is located within this region. In 84 families affected by schizophrenia or schizo-affective disorder no tendency toward increased allele sharing amongst siblings was observed (chi(2) = 0.002). We conclude either that this region does not include a gene predisposing to psychosis or that if it does, the relevant variation is epigenetic rather than sequence-based. With respect to the latter possibility we draw attention to the recent evolutionary history of the Xq21.3/Yp region. Genes within the region are in transition to protection from X inactivation and therefore may be epigenetically labile., (Copyright 2002 Wiley-Liss, Inc.)