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Purpose: We compared various clinical characteristics of pediatric-onset psychogenic nonepileptic seizures (PNES) between patients from five countries. The purpose of this study was to advance our understanding of pediatric-onset PNES cross-culturally.Methods: In this retrospective study, we compared consecutive patients with PNES with an age at onset of 16 years and younger from epilepsy monitoring units in Iran, Brazil, the USA, Canada, and Venezuela. Age, gender, age at seizure onset, seizure semiology, predisposing factors, and video-EEG recordings of all patients were extracted. Pearson Chi-Square, one-way ANOVA and Bonferroni correction tests were used for statistical analyses.Results: Two hundred twenty-nine patients were studied (83 from Iran, 50 from Brazil, 39 from Canada, 30 from the USA, and 27 from Venezuela). Mean age at the onset of seizures was 12.1 ± 3.2 years (range: 4-16 years). The sex ratio of the patients was 1.83: 1 (148 females and 81 males). Clinical characteristics of pediatric-onset PNES showed some significant differences among the nations. However, factors associated with pediatric-onset PNES in these five nations were similar.Conclusion: This study underscores how international cross-cultural studies can make important contributions to our understanding of PNES. Patients with pediatric-onset PNES from different countries were similar on many risk factors associated with PNES. This suggests universality in many features of PNES. However, intriguing differences were also noted with regard to seizure semiology, which might be the result of cultural factors. [ABSTRACT FROM AUTHOR]

In early postcolonial Tanzania, female students represented the future of the country and, as such, enjoyed more access to state-sponsored schooling than previous generations; they also developed a distinct youth culture, engaged in state sponsored youth organizations and participated in nation-building activities. At the same time, the new holders of Tanzanian state power, overestimating their reforming capabilities, demanded unprecedented intimacy into the lives of female students and, in the name of nation-building, worked to subject students to their coercive protection through intrusive testing and examination. Those found pregnant were deemed immoral and expelled from school. In response, female school-goers contested such demands over citizenship, highlighted the leaders' hypocrisy and even disregarded government imposed rules. Overall, this article connects gender and generation with the larger project of contesting the development of a new, patriarchal national culture, paradigms of economic development and a new puritanism, a trend evident throughout the postcolonial world. [ABSTRACT FROM AUTHOR]

A method to characterise rheological and microstructure features of whole digesta collected from pigs fed meat-containing western style diets is described. Digesta are shown to contain suspensions of meat fibre particles up to 300 μm in size which exhibit weak gel behaviour, have a dynamic viscosity higher than steady shear viscosity indicative of structural breakdown at the initiation of flow, and shear thinning behaviour under steady shear. The power law index approach is useful for capturing the overall features of rheological behaviour under both small ( n *<0.3) and large deformation (typically 0.2 < n < 0.5) conditions. Values obtained for rheological parameters represent a balance between the digestion of structural components (meat particles and starch granules in this case) with the absorption of water along the small intestine, and result in the absence of any systematic pattern as a function of small intestinal site. Both primary rheological data ( G ′, G ″, η , η *) and power law index parameters show a high level of variability between animals fed identical diets. This study provides a baseline from which to investigate the in vivo effects of hydrocolloids on the rheology of porcine digesta from diets representative of human meals. [ABSTRACT FROM AUTHOR]

Abstract: 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

Abstract: The condition now known as conversion disorder has been described since the time of Hippocrates. It was of great interest to many pioneers of neurology and psychiatry in the late 19th and early 20th century, such as Charcot and Freud. Since this time, despite being a relatively common condition often leading to severe and persistent disability, it has received relatively little attention from the scientific community. Consequently there has been little progress in understanding its pathogenesis and in finding effective treatments. The focus of this article is the management of motor and sensory conversion disorder, primarily from the perspective of the psychiatrist. The historical context and terminology of the condition are reviewed to minimize confusion and aid communication with both patients and other professionals. Diagnostic issues are explored along with potential psychological and neural mechanisms, revealing evidence for previous emotional trauma as a risk factor and the possible role of stressful life events preceding symptom onset. A guide to assessing suspected conversion disorder is provided, paying particular attention to what it is necessary to check before the assessment begins In order to maximize the chances of therapeutic engagement. The clinical features that help exclude neurological disorder and support conversion disorder are explained. There are no proven treatments specifically for conversion disorder, but current practice is reviewed along with the limited evidence base. [Copyright &y& Elsevier]

• OCD logically would be expected to be impacted by the Covid-19 pandemic situation, including due to commonality of contamination/washing symptoms. • Longitudinal data in clinical settings suggested marked symptom worsening in 20–65 % of OCD patients; but that not all patients experience a worsening, and some experience improvement. • Cross-sectional data from general population studies implicated trait compulsivity and pandemic-related stress in OCD symptoms during the pandemic. • Studies should examine neuropsychiatric sequelae of Covid-19; and they should incorporate validated measures to quantify emergence/worsening of OCD symptoms. There has been much speculation about untoward effects of the Covid-19 pandemic on psychological symptoms. OCD may be expected to be especially impacted. Our aim was to distil the current evidence base on relationships between the pandemic and obsessive-compulsive symptoms, in patients, and general population samples. We conducted a rapid scoping review, in the form of a systematic literature search, coupled with narrative review. 32 relevant papers were identified. (1) A sizable proportion of people with OCD (but not all) experienced/reported symptom worsening during the pandemic, especially during initial restrictions (approximately 20–65 % of cases in longitudinal studies); (2) contamination/washing symptoms appeared particularly susceptible; and (3) OCD symptoms in general population samples were associated with trait compulsivity and pandemic-related-stress. The literature was heterogeneous with various methodological issues being commonplace. The review identified important unaddressed issues: how should exposure based therapy be adapted during pandemics? How can we minimise harm from exacerbation of OCD in vulnerable individuals arising from public health messaging? Why do some but not all OCD patients experience worsening? And does Covid-19 infection affect (or lead to) OCD symptoms? [ABSTRACT FROM AUTHOR]

Abstract Saline water is widely used in coal preparation plants and problems are seen in these plants that a large amount of coal froth accumulates on top of thickeners in settling, the first step of dewatering process. However, the influence of saline water on settling in dewatering of coal froth products was rarely investigated. In this study, settling of coal slurry and coal froth in three different types of saline water was investigated. It turned out that saline water accelerated the settling velocity of particles that detached from froth, while increasing the amount of froth floating on top of water. The two effects both presented in settling of coal slurry and coal froth, however, the accelerated settling velocity of detached particles by salinity was more pronounced in settling of coal slurry, and the increased amount of froth by salinity was more pronounced in settling of coal froth. The mechanisms underpinning the two effects were investigated through Scanning Electron Microscopy (SEM) and oscillatory rheology. For particles detached from froth, saline water enhanced the particle attraction in coagula, so the coagula size increased and therefore the settling speed of particles also increased with water salinity. For coal froth, the balance of forces on particles determined the state of particles. Capillary attraction and buoyancy force counteracted gravity force to hold particles in froth. The capillary attraction increased with water salinity, so did the amount of froth floating on top of water. Graphical abstract Unlabelled Image Highlights • Saline water accelerated the settling speed of particles detached from froth. • Saline water increased the amount of froth floating on top of water in settling. • Water salinity governed particle interactions in coal slurry and determined the coagula size. • Increased capillary attraction with salinity determined the froth volume on top of water. [ABSTRACT FROM AUTHOR]

Dewatering of fine coal flotation products is discouraged by the presence of stable coal froth, which is becoming a common problem in coal preparation plants, however, the underpinning mechanism is still unclear. In this study, the dewatering behaviours of fine coal flotation products in both thickening and filtration were investigated and compared with those of coal slurry under the same condition. The mechanism that how coal froth influenced dewatering was investigated by analysing the froth properties using oscillatory rheology in conjunction with the characterization of particle arrangements on the air-water interface using Scanning Electron Microscopy (SEM). It was found that, in the presence of air, particle interactions in coal froth were stronger than those in coal slurry, which was caused by the capillary attractive force between particles on the air-water interface. In addition, particles in coal froth were arranged regularly, while particles in coal slurry were distributed randomly. Strong particle interactions and well organised structures in coal froth made the capillary radii smaller, and as a result, a large amount of froth stabilized on top of water during settling and the final moisture of filter cake was high in filtration. [ABSTRACT FROM AUTHOR]

The previous study demonstrated that bentonite had a deleterious effect on copper flotation by increasing pulp viscosity, but this deleterious effect could be mitigated by sea water (Zhang et al., 2015a). In this study, the effect of different cations, Na + , K + , Mg 2+ and Ca 2+ with the same anion, Cl − , on the rheology of a copper-gold ore in the presence of bentonite and copper flotation was investigated. It was found that the improvement of copper flotation in the presence of bentonite was generally dependent on the reduction of pulp viscosity by these cations. Divalent cations, Mg 2+ and Ca 2+ , had a more significant effect on pulp viscosity and therefore copper flotation than monovalent cation, Na + , K + . These cations also interacted with bentonite, with residual cations modifying the froth property. However, this modification was less significant in copper flotation in the presence of bentonite where pulp viscosity played a critical role. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 ≤3 mm. 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 >15 ml/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. [ABSTRACT FROM AUTHOR]

Clay minerals impose deleterious impacts on mineral processing. In this study, bentonite consisting primarily of montmorillonite and kaolin consisting primarily of kaolinite, were used to characterise the effect of clay minerals on copper flotation. It was found that bentonite and kaolin caused different issues in the process of flotation. Increasing the proportion of bentonite reduced the amount of froth on the top of slurry and decreased the copper recovery. On the other hand, increasing the kaolin content mainly decreased the copper grade with little effect on copper recovery and the bubbles on the top of froth became smaller with higher froth stability. The different roles of bentonite and kaolin in the flotation were associated with their unique properties. The findings in this study suggest that to mitigate the negative effect of clay minerals, different approaches might be applied according to specific problems caused by different clay minerals. [ABSTRACT FROM AUTHOR]

Abstract: β-Glucan is one of the most studied soluble dietary fibres, and is known for its positive effects on human health such as lowering glycemic responses and reducing serum cholesterol levels. Viscosity and diffusion phenomena are thought to play an important role in imparting these beneficial effects through interactions with digestive enzymes and bile salt micelles in the digestive tract. Correlations between viscosity, probe diffusivity, and molecular structure for three barley β-glucans are studied here to enhance understanding of the molecular basis for these nutritional effects. Fluorescence recovery after photobleaching (FRAP) is used to measure the diffusion coefficients of a dextran probe similar in size to both digestive enzymes and bile salt micelles in β-glucan solutions. Diffusion coefficients are found to decrease with an increase in the viscosity, but showed systematic deviations from Stokes–Einstein behaviour, similar to those found for cereal arabinoxylans, and thus indicating that bulk viscosity measurements cannot be reliably used as sole indicator of diffusion processes, due to local aggregation and microviscosity effects. The diffusion coefficient values are 10–100 times slower than predicted for diffusion in the absence of β-glucan, consistent with a functional role in retarding digestion and absorption processes in the small intestine. [Copyright &y& Elsevier]

Abstract: The rheological properties of thermoplastic starch (TPS) melt were investigated using the new multipass rheometer (MPR). This rheometer consists of two servo-hydraulically driven pistons and a fully closed barrel, enabling pressurisation of sample and preventing moisture loss during the process. The starch samples (with different plasticiser contents, 70–110%, and at different glycerol/water ratio, 1:4, 2:3, and 3:2) were first well transformed into TPS in MPR and then tested at different temperatures (90, 110 and 130°C). The TPS behaved as a shear-thinning material, and the power-law model was used to describe its rheological behaviour. The combination of glycerol and water had the greatest influence on the power-law index n while temperature had little influence. By mastercurve study, it was shown that the higher the glycerol/water ratio, the stronger the shear-thinning behaviour was. This was explained by interaction between starch and plasticiser and different structural characteristics at different conditions. [ABSTRACT FROM AUTHOR]

Abstract: Non-starch polysaccharides such as arabinoxylans have important roles in the human diet, resulting in potential benefits such as increased microbial fermentation, promotion of beneficial microflora, prevention of re-absorption of bile acids leading to lower plasma cholesterol, and retardation of starch digestion. The latter two beneficial effects may arise from viscosity and/or diffusion phenomena in the gastrointestinal tract. To study this, measurements of the viscosity and diffusion coefficients of a polymer probe similar in size to both bile salt micelles and alpha-amylase were carried out for water solutions of three arabinoxylans with differing viscosities. Diffusion coefficients were obtained using fluorescence recovery after photobleaching (FRAP). The concentration dependence of both viscosity and diffusion coefficients followed the usual behaviour of polymers for each of three arabinoxylan samples. However, at a given concentration, the sample with the highest viscosity also had the highest probe diffusion coefficient: the reverse of what would be expected for homogeneous solutions. This apparent anomaly is ascribed to differences in polymer structure between the three samples giving rise to varying levels of local polymer aggregation and consequent microvoids. These differences are verified using characterisation with multiple-detection size-exclusion chromatography. Deviations from simple Stokes–Einstein behaviour are ascribed to the existence of aggregates in solution. The results show that studies of the role of arabinoxylans in human nutrition cannot assume that the diffusion coefficients of species with sizes in the range important for digestive processes in a series of samples will increase with decreasing viscosity at a given concentration: diffusion coefficient and viscosity must be measured independently. [Copyright &y& Elsevier]

Abstract: 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. [Copyright &y& Elsevier]

Abstract: A range of comb polymers of poly(n-butyl methacrylate), where the degree of polymerization (DP) of both the backbone and branches was controlled using RAFT-mediated free-radical polymerization, was synthesized using the method of Vosloo et al. [Macromolecules 2004;37: 2371]. Individual architectural parameters (branch length, branch number and DP of the comb backbone) of these relatively monodisperse samples were systematically varied in order to study the impact of each structural parameter on the thermal and rheological properties of the resulting comb polymers. Differential scanning calorimetry showed lower glass transition temperatures for the comb polymers compared to the original linear backbones. There were negligible differences in glass transition temperatures between comb polymers containing branches of different lengths, and between comb polymers containing backbones of narrow and of broad molecular weight distributions. These observations suggest that because the comb polymers are very tightly spaced, the branches act in the same way as long chain polyBMA. Viscoelastic properties of the comb polymers were investigated using dynamic mechanical analysis, using time–temperature superposition to extend the rheological data over a wide frequency range. Major differences in the viscoelastic responses of the original linear backbones and the comb polymers were observed, which were explained in terms of arm retraction/relaxation leading to tube dilation. All comb polymers showed viscoelastic responses that are characteristic of combs, but differences in responses due to changes in branch length and branch number were difficult to detect. This was mainly due to the relatively high number of branches, whose retractions occurred over a broad frequency range, and thus dominated the observed changes in moduli, thereby possibly masking subtle differences in responses. [Copyright &y& Elsevier]

Altered interoception may be a pathophysiological mechanism in functional neurological disorder (FND). However, findings have been inconsistent across interoceptive dimensions in FND including functional motor symptoms (FMS) and seizures (FS). Here, individuals with FMS/FS (n = 17) and healthy controls (HC, n = 17) completed measures of interoceptive accuracy and insight (adapted heartbeat tracking task [HTT] with confidence ratings), a time estimation control task (TET) and the Multidimensional Assessment of Interoceptive Awareness–2 (MAIA-2) to assess interoceptive sensibility. The groups did not differ in interoceptive accuracy (p = 1.00, g = 0.00) or confidence (p =.99, g = 0.004), although the FMS/FS group displayed lower scores on the "Not-Distracting" (p <.001, g = 1.42) and "Trusting" (p =.005, g = 1.17) MAIA-2 subscales, relative to HCs. The groups did not differ in TET performance (p =.82, g = 0.08). There was a positive relationship between HTT accuracy and confidence (insight) in HCs (r =.61, p =.016) but not in FMS/FS (r = 0.11, p =.69). HTT confidence was positively correlated with MAIA-2 "Self-Regulation" (r = 0.77, p =.002) and negatively correlated with FND symptom severity (r = −0.84, p <.001) and impact (r = −0.86, p <.001) in FMS/FS. Impaired interoceptive accuracy may not be a core feature in FMS/FS, but reduced insight and altered sensibility may be relevant. Reduced certainty in self-evaluations of bodily experiences may contribute to the pathogenesis of FND symptoms. • Intact interoceptive accuracy in functional motor symptoms/seizures (FMS/FS). • Potentially reduced interoceptive insight in FMS/FS versus healthy controls (HC). • Lower levels of "Trusting" and "Not-Distracting" in FMS/FS compared to HC. • Elevated "Self-regulation" positively related to interoceptive confidence in FMS/FS. • Elevated symptom severity/impact negatively related to interoceptive confidence. [ABSTRACT FROM AUTHOR]

The photo-oxidative degradation of two complementary linear low density polyethylene (LLDPE) films has been studied: a Ziegler-Natta catalysed 1-octene copolymer (ZN-LLDPE) and a 1-octene copolymer produced by a single site constrained catalyst (m-LLDPE). The degradation processes were followed using a range of characterisation techniques including tensile testing, GPC, MAS-NMR, FTIR, WAXS and SAXS. The chemical species formed on degradation were similar for both polymers. Both also showed an increase in crystallinity and modulus with UV ageing time and a decrease in the long spacing of the lamella. However, the m-LLDPE showed a significantly shorter time to embrittlement than the ZN-LLDPE, which correlated in both polymers with the disappearance of the second yield point. The major observed difference in crystalline structure was a significantly higher interfacial thickness between the crystalline lamellae and the amorphous regions for the ZN-LLDPE, which decreased rapidly on UV ageing. This difference in behaviour was attributed to the nature of the branching in the ZN-LLDPE, which was presumed to sit in blocks along the chain and thus to reside in the interfacial regions. Cleavage of the tertiary carbons in these interfacial regions was less damaging to the mechanical properties than for the m-LLDPE, where chain scission broke more of the tie molecules, thus limiting the ability of the polymer to draw. . This work advances our understanding of polymer microstructural evolution during degradation and the implications of initial polymerisation route and molecular structure on the degradation mechanisms. [ABSTRACT FROM AUTHOR]

Bentonite is used for landfill application because of its high sealing ability. Following the swelling phenomenon the water reacts with the bentonite and expands the solid particles. The voids are filled and this reduces permeability of the soil. However, the drawback is the long time needed to assess the hydraulic performance, whereas the engineers require simple and rapid characterization parameters to design the hydraulic barrier. Present paper investigates the possibility of use of rheology testing to describe the swelling properties of bentonite used for geotechnical engineering issues. Rheology testing is proposed to investigate the swelling properties of different nature of bentonite. Different types of bentonite are tested: natural sodium, natural calcium and sodium-activated-calcium bentonites. Rheological measurements are performed in steady and dynamic conditions. Free swell and oedometer swell tests are also performed and compared. A simple model is proposed to unify the output parameters of the liquid-state bentonite from two rheology tests, with the ones obtained from two swelling tests. This approach propose a single parameter: the swelling ratio β that describes the layer of water surrounding the particles based on the aspect ratio of bentonite packed particles. The method highlights the correlation between swelling characteristics and rheological parameters of bentonites. The results of swelling ratio underline distinctly the difference of mineralogy between the groups of bentonites. A linear equation fits the values of β obtained from the two swelling tests and the values of β obtained from the rheology tests, for all bentonites. Low correlations are observed between the oedometer swelling ratio and the rheology ratio. But, the free swelling ratio is in good agreement with rheological ratio and demonstrates a stronger correlation between the steady state rheology ratio than the dynamic state rheology ratio. [ABSTRACT FROM AUTHOR]

Abstract: 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 10.8/1mol/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 &y& Elsevier]

Abstract: Film embrittlement criteria were determined for photo-oxidative degradation of linear low density polyethylene (LLDPE) films by using a range of characterisation techniques: tensile, high-temperature GPC, MAS-NMR, FTIR-ATR, WAXS and SAXS. The key embrittlement criteria was the loss of 95% elongation at break and the reduction in interlamellar distance, reduced down to approximately 30–50 Å, as a result of recrystallisation of mobile short chain fragments produced from chain scission reaction. Interlamellar thinning correlated well with the changes in double yield points seen in the tensile data, where the absence of the second yield point signified that the tie molecules at the lamellar interface underwent chain scission and could no longer transfer the tensile stress to reach c-axis slip of the lamellar crystals. This was also supported by a reduction in amorphous–lamellar interfacial width with ageing time, extracted from SAXS data using the linear correlation function. [Copyright &y& Elsevier]

Abstract: Multi-walled carbon nanotube (MWCNT)/polymethyl methacrylate (PMMA) composites with loadings ranging from 0.1 to 1.0wt.% were prepared for use as bone cement. Unfunctionalised, carboxyl and amine functionalised MWCNT were used. Thermal properties were characterised in accordance with the International Standard for acrylic cements, ISO 5833:2002. The rate of reaction exotherm generated and thermal necrosis index (TNI) values were calculated. Polymerisation kinetics were characterised using parallel plate rheology and the exotherm during polymerisation was reduced by ≈4–34%, as a consequence of the MWCNT thermal conductivity. The rate of reaction was significantly altered, such that the setting times of the cements were extended (≈3–24%). Consequently, significant decreases in TNI values (ranging from 3% to 99%) were recorded, which could reduce the exothermic temperatures experienced in vivo and therefore prevent the likelihood of polymerising PMMA cement causing thermally-induced bone tissue necrosis. Thermal data was supported by the rheological characterisation results. Onset of polymerisation for PMMA cement exhibited a strong linear increase as a function of MWCNT loading, however, polymer gelation was not affected to the same degree. It is proposed that the chemically functionalised MWCNT altered PMMA bone cement polymerisation kinetics, reducing the rate of polymerisation, and hence, the reaction exotherm. [Copyright &y& Elsevier]

Abstract: A peroxide-initiated melt compounding technique was used to graft and crosslink the high density polyethylene/chitosan blend using vinyl triethoxysilane. Different percentage of chitosan (up to maximum of 35%) was added in HDPE/chitosan blends. The physical and functional properties of the crosslinked HDPE/chitosan blends were investigated and compared with its non-crosslinked congener. IR spectrum of crosslinked blend confirmed the presence of Si–O–Si and Si–O–C absorption peaks at 1020cm−1 and 1105cm−1. Increased gel content was obtained with increasing chitosan loading whereas percentage crystallinity was decreased. Rheological study of crosslinked blends showed linear viscoelastic behavior with high complex viscosity and dynamic shear storage modulus. Tensile strength of crosslinked HDPE was 9.3MPa and it was increased by threefold to 27.4MPa in crosslinked HDPE/chitosan blends containing 35% chitosan contents. Similarly lower deformation was observed in crosslinked blends under static load. Scanning electron microscopy revealed good adhesion between matrix–filler interphase. [ABSTRACT FROM AUTHOR]

Abstract: d-Limonene was encapsulated with β-cyclodextrin to improve its retention during pre-added flavour starch extrusion. The objective of this work was to determine the effect of processing condition on the flavour retention and extrudate properties. Corn starch containing five levels of β-cyclodextrin-d-limonene capsules (0–5%) were extruded at five different maximum barrel temperatures (133–167°C) and screw speeds (158–242rpm) using a twin screw extruder. The effect of these parameters on the flavour retention, expansion, texture, colour difference (ΔE), Water Absorption Index, Water Solubility Index, and residence time distribution (RTD) were investigated. Barrel temperature and capsule level predominantly influenced flavour retention and extrudate properties, while screw speed primarily affected extruder performances such as torque, die pressure, specific mechanical energy and RTD. [Copyright &y& Elsevier]

• Viruses and immune function have been associated with psychosis through genetic and epidemiological research. • We critically evaluate the case for psychosis in COVID-19 through analysis of reported cases and historical precedents. • Potential infectious, post-infectious and neurodevelopmental aetiologies are explored. • Further appraisal of potential neurobiological and psychosocial mechanisms of 'COVID-19 psychosis' is urgently needed. Historical epidemiological perspectives from past pandemics and recent neurobiological evidence link infections and psychoses, leading to concerns that COVID-19 will present a significant risk for the development of psychosis. But are these concerns justified, or mere sensationalism? In this article we review the historical associations between viral infection and the immune system more broadly in the development of psychosis, before critically evaluating the current evidence pertaining to SARS-CoV-2 and risk of psychosis as an acute or post-infectious manifestation of COVID-19. We review the 42 cases of psychosis reported in infected patients to date, and discuss the potential implications of in utero infection on subsequent neurodevelopment and psychiatric risk. Finally, in the context of the wider neurological and psychiatric manifestations of COVID-19 and our current understanding of the aetiology of psychotic disorders, we evaluate possible neurobiological and psychosocial mechanisms as well as the numerous challenges in ascribing a causal pathogenic role to the infection. [ABSTRACT FROM AUTHOR]