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The threshold voltage for electro-hydrodynamic convection (EHC) in nematic liquid crystals in the low-frequency convective regime is examined. The addition of dopant species is known to strongly effect the frequency response of this regime. In this work, we investigate the effect of adding optically anisotropic species on the low-frequency threshold, and, demonstrate that certain dichroic dyes have a marked effect. We have measured electrical transport properties of suitably doped liquid crystal mixtures in order to make a comparison with theoretical predictions based upon linear stability considerations. Our results show satisfactory agreement with these predictions. Our findings indicate future directions for new applications of dynamic scattering mode technologies with more accessible operating parameters previously known. [ABSTRACT FROM AUTHOR]

The majority of dietary nutrient absorption occurs in the small intestine, with the intestinal epithelium acting as a barrier to the contents of the intestinal lumen. This barrier is maintained by intestinal epithelial cells, which support nutrient uptake but prevent translocation of bacteria, allergens and toxins. There is complex signalling and interaction between intestinal epithelia, macrophages, luminal contents and the microbiota which can modulate epithelial paracellular porosity. Intake of alcohol, fatty acids, pharmaceuticals and pathogenic bacteria has been reported to increase paracellular permeability, increase production of pro-inflammatory cytokines and temporarily reorganise tight junctional proteins. Conversely, numerous probiotics, nutraceuticals and food-derived bioactive components are promising due to reported restoration of intestinal barrier integrity by increasing production of anti-inflammatory cytokines and increased expression of tight junctional proteins. In vitro co-culture models exist and recent advances in microfluidic in vitro models are promising tools for investigating the complex effect of dietary components on the intestinal barrier. Temporarily perturbing the intestinal barrier may increase the oral bioavailability of therapeutic molecules. However, people with impaired intestinal integrity ( e.g. those with Crohn's, coeliac or ulcerative colitis disease) should avoid foods which further perturb barrier integrity, while increasing intake of specific foods and possibly probiotics to promote intestinal barrier restoration. [ABSTRACT FROM AUTHOR]

This paper considers the role of the teacher in relation to moral education in Catholic schools in Australia and Ireland. Literature pertaining to faith-based schooling, the moral role of the teacher and moral education across the curriculum in both countries is outlined. The paper draws on a small-scale study involving a survey with 154 respondents and individual interviews with nine teachers. Some interesting country differences emerged that are indicative of cultural settings. These include pedagogical practices, the nature of teacher–student relationships and levels of awareness of schools' founding charisms. Some implications for moral education in faith-based schools are identified. [ABSTRACT FROM AUTHOR]

The dissonance between the socialisation experiences of student teachers during their own schooling and practicums and university-based teacher education programmes is indicative of the broader theory/practice dichotomy in education. While this dichotomy is of considerable interest to all teacher educators, studies of students’ pre- and post-placement professional beliefs are rare. The authors availed of the publication of alternative curriculum pathways for Ireland to investigate the curriculum beliefs of student teachers immediately before and after their final school placement. Important contextual aspects of the study including school and teacher culture and the proposed curriculum pathways are introduced. The stark contrast between student teachers’ preferences and their views regarding the feasibility of the various pathways and their commitment to pupil-centred learning are among the main findings of the current study. A positive relationship emerged between respondents’ curriculum preferences and their grades in curriculum studies. These emerging themes are considered from the perspectives of student teachers’ beliefs about pupil learning, the theory/practice dichotomy and the importance of developing school–university partnerships. [ABSTRACT FROM PUBLISHER]

This paper reports a longitudinal study of levels of moral reasoning in a convenience sample of Irish undergraduate university students, using the Defining Issues Test 2 (DIT2). The study was timely, as higher education institutions are becoming increasingly interested in the promotion of social capital and the development of the whole person. A total of 259 students completed the DIT2 at the beginning, mid-point and conclusion of their degree course. As with similar international studies, increases in levels of moral reasoning over time were statistically significant. However, Irish students' DIT2 scores were markedly lower than their international peers with 62% of graduating students at the pre-conventional and conventional stages. The paper suggests some context-related explanations for the under-performance of Irish students including the instrumentalist nature of Irish post-primary education, the prevailing culture of consensualism, authoritarianism and anti-intellectualism, the conflation of religious and moral education and the emphasis on economic outputs and contractual accountability. [ABSTRACT FROM AUTHOR]

BackgroundIn recent years there has been increasing interest in functional recovery in the early phase of schizophrenia. Concurrently, new remission criteria have been proposed and several studies have examined their clinical relevance for prediction of functional outcome in first-episode psychosis (FEP). However, the longitudinal interrelationship between full functional recovery (FFR) and symptom remission has not yet been investigated. This study sought to: (1) examine the relationships between FFR and symptom remission in FEP over 7.5 years; (2) test two different models of the interaction between both variables.MethodAltogether, 209 FEP patients treated at a specialized early psychosis service were assessed at baseline, 8 months, 14 months and 7.5 years to determine their remission of positive and negative symptoms and functional recovery. Multivariate logistic regression and path analysis were employed to test the hypothesized relationships between symptom remission and FFR.ResultsRemission of both positive and negative symptoms at 8-month follow-up predicted functional recovery at 14-month follow-up, but had limited value for the prediction of FFR at 7.5 years. Functional recovery at 14-month follow-up significantly predicted both FFR and remission of negative symptoms at 7.5 years, irrespective of whether remission criteria were simultaneously met. The association remained significant after controlling for baseline prognostic indicators.ConclusionsThese findings provided support for the hypothesis that early functional and vocational recovery plays a pivotal role in preventing the development of chronic negative symptoms and disability. This underlines the need for interventions that specifically address early psychosocial recovery. [ABSTRACT FROM PUBLISHER]

Urban impervious areas provide a guaranteed source of runoff, especially in cities with high rainfall - this represents a source of water with low sensitivity to unfavourable climate change. Whilst the potential to reuse stormwater has long been recognised, its quality has largely limited usage to non-potable applications requiring the use of a third-pipe network, a prohibitively expensive option in established urban areas. Given recent advances in membrane filtration, this study investigates the potential of harvesting and treating stormwater to a potable standard to enable use of the potable distribution network. A case study based on the Throsby Creek catchment in Newcastle explores the issue. The high seasonally uniform rainfall provides insight into the maximum potential of such an option. Multicriterion optimisation was used to identify Pareto optimal solutions for harvesting, storing and treating stormwater. It is shown that harvesting and treating stormwater from a 13 km2 catchment can produce yields ranging from 8.5 to 14.2 ML/day at costs ranging from AU$2.60/kL to AU$2.89/kL, which may become viable as the cost of traditional supply continues to grow. However, there are significant social impacts to deal with including alienation of public land for storage and community acceptance of treated stormwater. [ABSTRACT FROM AUTHOR]

Background. Little research has focused on delineating the specific predictors of emotional over-involvement (EOI) and critical comments (CC) in the early course of psychosis. The purpose of this study was to investigate the differential relationships of EOI and CC with relevant predictors in relatives of first-episode psychosis (FEP) patients. Method. Baseline patient-related factors including psychotic symptoms, depression and duration of untreated psychosis (DUP) and carer attributes comprising CC, EOI, burden of care and carers' stress and depression were assessed in a cohort of 63 remitted FEP patients and their relatives. Carers were reassessed at 7 months follow-up. Results. Baseline analysis showed that EOI was more strongly correlated with family stress compared with CC, whereas CC yielded a stronger association with DUP than EOI. Carers' CC at follow-up was not significantly predicted by either baseline family stress, burden of care or patient-related variables. Conversely, baseline EOI predicted both family stress and burden of care at 7 months follow-up. Finally, family burden of care at follow-up was a function of baseline EOI and patients' depressive symptoms. Conclusions. This study provides preliminary support to the postulate that EOI and CC may be influenced by separate factors early in the course of psychosis and warrant future research and therapeutic interventions as separate constructs. Implications for family interventions in the early phase of psychosis and the prevention of CC and EOI are discussed. [ABSTRACT FROM AUTHOR]

Adrienne Willcox and Judy Gleeson explore the issues around educating boys on teenage pregnancy. [ABSTRACT FROM AUTHOR]

Objectives: We investigated the effect of the therapeutic alliance on both change in social recovery outcomes and usage of a moderated online social therapy platform for first‐episode psychosis (FEP), Horyzons. Design: Secondary analysis of a single group pilot trial. Methods: Clients completed an alliance measure adapted for guided digital interventions at mid‐treatment. A series of multi‐level models evaluated change in outcomes by mid‐ and post‐treatment assessments (relative to baseline) as a function of the overall alliance. Quasi‐Poisson models evaluated the effect of the overall alliance on aggregated counts of platform usage. Exploratory analyses repeated these models in terms of the bond (human–human) or the task/goal (human–program) alliance. Results: Stronger overall alliance at mid‐treatment predicted lower loneliness at mid‐treatment and lower social anxiety at mid‐ and post‐treatment. It was also associated with higher completion of therapy activities and authoring of comments and reactions. A strong bond with an online therapist was associated with lower loneliness and higher perceived social support at mid‐treatment, lower social anxiety at post‐treatment as well as a higher number of reactions made on the social network. Stronger alliance with the platform's tasks and goals facilitated lower social anxiety at both follow‐up assessments and was further associated with higher completion of therapy activities and reactions in the social network. Conclusions: The alliance may impact aspects of social recovery and usage in digital interventions for FEP. Specific aspects of the alliance (human–human and human–program relationships) should be considered in future research. [ABSTRACT FROM AUTHOR]

We report an approach for generating truly random digital numbers. This approach is based on probing the chaotic and unpredictable fluctuations that take place in a nematic liquid crystal when it is undergoing turbulent, electrically induced, convective flow. This technique generates a stream of numbers that passes standard benchmark tests for randomness. A device utilizing this technique is not only inexpensive to construct, but also tamper proof. We discuss various strategies for improving the operating characteristics, primarily the bit generation rate, of a device constructed on this principle. [ABSTRACT FROM AUTHOR]

This discussion paper considers the identification and definition of the ‘characteristic spirit’ of publicly managed schools in the Republic of Ireland. Some international approaches to values in publicly funded schools are introduced along with relevant contextual aspects of Irish education including the cultural diversity and secularisation of modern Irish society. The Irish Education Act (1998) gives ultimate responsibility for school values and ‘characteristic spirit’ to the school ‘patron’, a role legally separate from that of school ownership and school management. The underlying values of privately managed faith-based schools are well established. However, the ‘characteristic spirit’ of publicly managed Education and Training Board schools remains largely undeveloped. Appropriate responses to this challenge are identified and discussed. [ABSTRACT FROM AUTHOR]

Treatment guidelines for first episode psychosis (FEP) recommend at least 1 year of antipsychotic treatment following remission; however, in light of some recent research and the preference of some individuals to discontinue their medication sooner, this recommendation can be questioned. The aim of this article is to appraise the current discontinuation studies given our views on how this field should progress. We conducted a review of randomized controlled trials investigating dose-reduction/medication discontinuation compared with treatment maintenance in clinically remitted FEP patients. Seven trials were identified, and these reported a higher rate of relapse in the dose reduction or discontinuation groups. Relapse rates were higher when a lower threshold for relapse was utilized. However, only three studies specified that concurrent psychosocial interventions were also provided, despite an evidence base for these interventions in reducing symptom severity and relapse. Length of follow-up may also be important, as the study with the longest follow-up (7 years), albeit with some methodological shortcomings, found greater functional recovery in the dose-reduction group and that relapse rates between the two groups (dose-reduction vs. maintenance) were equal after 3 years. Finally, in addition to discontinuation or dose reduction, a diagnosis of schizophrenia, a longer duration of illness, and poor premorbid functioning were associated with a greater risk of relapse. Further trials are needed in this area to establish the long-term risk-benefit ratio of antipsychotic medication in FEP. Meanwhile, young people with FEP who do not fulfil criteria for a diagnosis of a schizophrenia disorder, achieve clinical remission for at least 3 months, attain early functional recovery, and have good social support may be possible candidates for discontinuation of antipsychotic medication bolstered by effective psychosocial interventions provided in the context of a specialized FEP service. [ABSTRACT FROM AUTHOR]

We report small angle x-ray scattering (SAXS) studies of isotropic, nematic, and smectic mesophases formed by binary mixtures of bent-core (BC) and rod-shaped (RS) molecules. While optical studies indicate that the components are fully miscible, SAXS reveals fascinating structures that are consistent with segregation on a nanoscopic scale. We find that tilted smectic clusters, which have been previously reported in both the nematic and isotropic states of the pure BC materials, are also present in mixtures with up to 50 wt% of the RS compound; this is consistent with previous dielectric and flexoelectric studies on such mixtures. Unexpectedly in this concentration range the clusters are present in the isotropic and in the induced smectic phase range, as well as throughout the nematic phase. The results in the smectic phase also reveal complex layering phenomena, providing important insight into the interaction between bent and rod-shaped molecules. These studies will be crucial in the design of promising new functional nanomaterials. [ABSTRACT FROM AUTHOR]

Viscosity measurements are reported for a bent-core nematic liquid crystal, 4- chloro-1,3-phenylenebis{4-[4'-(9-decenyloxy)benzoyloxy]} benzoate (ClPbis10BB). The rotational viscosity was measured by analysing the dynamics of director rotation in pulsed magnetic fields, and the flow viscosities were determined by employing a new electro-rotation technique. The results show that whereas the rotational viscosity is more than ten times larger than for calamitic liquid crystals, the flow viscosity is more than 100 times larger. Even more striking is the difference between the ratio of the flow and rotational viscosities, which for calamitic nematics is typically 0.1, whereas in this bent-core material it is ∼50. This suggests that the large shear viscosity is primarily due not so much to the molecular size, but rather the shape. A model is discussed that may explain the observations. [ABSTRACT FROM AUTHOR]

Background: The onset of mental disorders typically occurs between the ages of 12 and 25, and the burden of mental health problems is the most consequential for this group. Indicated prevention interventions to target individuals with subclinical symptoms to prevent the transition to clinical levels of disorders, even leading to suicide, have shown to be effective. However, the threshold to seek help appears to be high. Digital interventions could offer a solution, especially during the Covid-19 pandemic. This implementation study will investigate the digital indicated prevention intervention ENgage YOung people Early (ENYOY), the Dutch version of the original Moderated Online Social Therapy Platform (MOST+) from Australia. In addition, the relationship between stress biomarkers, symptoms and outcome measures of youth using the platform will be investigated in this study. Methods: The MOST+ platform will be adapted, translated and developed for the situation in the Netherlands in collaboration with a Youth Panel. A prospective cohort of 125 young people (16–25 years) with beginning mental health complaints will be on the platform and followed for a year, of which 10 participants will have an additional smart watch and 10 participants will be asked to provide feedback about the platform. Data will be collected at baseline and after 3, 6 and 12 months. Outcome measures are Psychological Distress assessed with the Kessler Psychological Distress Scale (K10), Social and occupational functioning (measures by the SOFAS), positive mental health indicators measured by the Positive Health Instrument, stress biomarkers with a smart-watch, website journeys of visitors, and feedback of youth about the platform. It will be a mixed-method study design, containing qualitative and quantitative measures. Discussion: This trial will specifically address young people with emerging mental health complaints, and offers a new approach for treatment in the Netherlands. Considering the waiting lists in (child and adolescent)-psychiatry and the increase in suicides among youth, early low-threshold and non-stigmatizing help to support young people with emerging psychiatric symptoms is of crucial importance. Moreover, this project aims to bridge the gap between child and adolescent and adult psychiatry. Trial registration: Netherlands Trial Register ID NL8966, retrospectively registered on the 19th of October 2020. [ABSTRACT FROM AUTHOR]

Myelomeningocele (MMC) affects one in 1000 newborns annually worldwide and each surviving child faces tremendous lifetime medical and caregiving burdens. Both genetic and environmental factors contribute to disease risk but the mechanism is unclear. This study examined 506 MMC subjects for ultra-rare deleterious variants (URDVs, absent in gnomAD v2.1.1 controls that have Combined Annotation Dependent Depletion score ≥ 20) in candidate genes either known to cause abnormal neural tube closure in animals or previously associated with human MMC in the current study cohort. Approximately 70% of the study subjects carried one to nine URDVs among 302 candidate genes. Half of the study subjects carried heterozygous URDVs in multiple genes involved in the structure and/or function of cilium, cytoskeleton, extracellular matrix, WNT signaling, and/or cell migration. Another 20% of the study subjects carried heterozygous URDVs in candidate genes associated with gene transcription regulation, folate metabolism, or glucose metabolism. Presence of URDVs in the candidate genes involving these biological function groups may elevate the risk of developing myelomeningocele in the study cohort. [ABSTRACT FROM AUTHOR]

Background: Spastic paraplegia 11 (SPG11) is defined as progressive spasticity and weakness of the lower limbs and also associated with mild intellectual disability with learning difficulties in childhood and/or progressive cognitive retardation, peripheral neuropathy, pseudobulbar symptoms, and increased reflexes in the upper limbs. We describe the clinical, laboratory, and radiological presentation of SPG11 through a report of a case and compare with previously reported SPG11 cases in the literature. Case presentation: This case presents a homozygous variant in the SPG11 gene (NM_025137.4): c.1699C>T;p.(Gln567*). Conclusion: The diagnosis was made based on molecular findings, thinning of corpus callosum (TCC) and in most cases, periventricular white matter abnormalities are detected in brain MRI. Therefore, the clinical and radiological findings are supporting the diagnosis. However, it should not be forgotten that TCC is not peculiar to SPG11. [ABSTRACT FROM AUTHOR]

Purpose: Loneliness is a challenge for individuals with psychosis; however, interventions rarely target loneliness in this group.Method: We developed a pilot positive psychology group intervention designed to reduce loneliness in psychosis and examined its feasibility and acceptability.Results: Sixteen participants attended 5.38 (SD = 0.70) out of six sessions, with a dropout rate of 10%. Participants were significantly less lonely at post-treatment (p < 0.001, d = 1.51), and maintained their improvements from post-treatment to follow-up (p = 0.81, d = 0.07).Conclusions: Loneliness may be a feasible and acceptable treatment target within psychosocial treatments. [ABSTRACT FROM AUTHOR]

We report the induction of spontaneously undulated chiral nematic structures of liquid crystal (LC) dimers with rigid aromatic molecular arms linked by flexible chains with an odd number of carbons. When a small amount of chiral dopants (CD) are added to the dimers, we find the formation of different stripe textures on cooling 4–10 μm films in the nematic phase. The temperature where the stripes form depends on the film thickness and the direction of the stripes depends on the CD concentrations. We show that the experimentally observed stripes are due to undulation instabilities that spontaneously form as a result of the anomalously small bend elastic constant that prefers director bend instead of twist deformation, the opposite of the situation in usual cholesteric LCs. [ABSTRACT FROM PUBLISHER]

Somatic and germline duplications or activating mutations of AKT3 have been reported in patients with hemimegalencephaly and megalencephaly. We performed array comparative genomic hybridization on brain tissue and blood in 16 consecutive patients with symptomatic epilepsy due to focal or multilobar malformations of cortical development who underwent surgical treatment of epilepsy. One patient with infantile spasms and a dysplastic left frontal lobe harboured a somatic trisomy of the 1q21.1-q44 chromosomal region, encompassing the AKT3 gene, in the dysplastic brain tissue but not in blood and saliva. Histopathology revealed severe cortical dyslamination, a thin cortex in the premotor area with microgyri and microsulci, immature neurons with disoriented dendrites and areas of cortical heterotopia in the sub-cortical white matter. These cytoarchitectural changes are close to those defining type Ib focal cortical dysplasia. Immunohistochemistry in brain specimens showed hyperactivation of the PI3K/AKT/mTOR pathway. These findings indicate that AKT3 upregulation may cause focal malformations of cortical development. There appears to be an etiologic continuum between hemimegalencephaly and focal cortical dysplastic lesions. The extent of brain malformations due to AKT3 upregulation may be related to the embryonic stage when the post-zygotic gene alteration occurs. [ABSTRACT FROM AUTHOR]

Angle-resolved, second-harmonic-light scattering (SHLS) measurements are reported for three different classes of thermotropic nematic liquid crystals (NLCs): polar and nonpolar rodlike compounds and a bent-core compound. Results revealing well-defined scattering peaks are interpreted in terms of the electric polarization induced by distortions of the nematic orientational field ("flexopolarity") associated with inversion wall defects, nonsingular disclinations, analogous to Neel walls in ferromagnets, that often exhibit a closed loop morphology in NLCs. Analysis of the SHLS patterns based on this model provides a "proof-of-concept" for a potentially useful method to probe the flexopolar properties of NLCs. [ABSTRACT FROM AUTHOR]

We present magneto-optic measurements on two materials that form the recently discovered twist-bend nematic Mb) phase. This intriguing state of matter represents a fluid phase that is orientationally anisotropic in three directions and also exhibits translational order with periodicity several times larger than the molecular size. Ntb materials may also spontaneously form a visible, macroscopic stripe texture. We show that the optical stripe texture can be persistently inhibited by a magnetic field, and a 25 T external magnetic field depresses the N-Ntb phase transition temperature by almost 1°C. We propose a quantitative mechanism to account for this shift and suggest a Helfrich-Hurault-type mechanism for the optical stripe formation. [ABSTRACT FROM AUTHOR]

We present magneto-optical measurements on two liquid crystals that exhibit a wide temperature-range amorphous blue phase (BPIII). Magnetic fields up to 25 T are found to suppress the onset of BPIII in both materials by almost 1 °C. This effect appears to increase nonlinearly with the field strength. The effect of high fields on established BPIIIs is also reported, in which we find significant hysteresis and very slow dynamics. Possible explanations of these results are discussed. [ABSTRACT FROM AUTHOR]

A majority of the global net primary production of mangroves is unaccounted for by current carbon budgets. It has been hypothesized that this "missing carbon" is exported as dissolved inorganic carbon (DIC) from subsurface respiration and groundwater (or pore-water) exchange driven by tidal pumping. We tested this hypothesis by measuring concentrations and δ13C values of DIC, dissolved organic carbon (DOC), and particulate organic carbon (POC), along with radon (222Rn, a natural submarine groundwater discharge tracer), in a tidal creek in Moreton Bay, Australia. Concentrations and δ13C values displayed consistent tidal variations, and mirrored the trend in 222Rn in summer and winter. DIC and DOC were exported from, and POC was imported to, the mangroves during all tidal cycles. The exported DOC had a similar δ13C value in summer and winter (~ -30‰). The exported δ13C-DIC showed no difference between summer and winter and had a δ13C value slightly more enriched (~ -22.5‰) than the exported DOC. The imported POC had differing values in summer (~ -16‰) and winter (~ -22‰), reflecting a combination of seagrass and estuarine particulate organic matter (POM) in summer and most likely a dominance of estuarine POM in winter. A coupled 222Rn and carbon model showed that 93-99% of the DIC and 89-92% of the DOC exports were driven by groundwater advection. DIC export averaged 3 g C m-2 d-1 and was an order of magnitude higher than DOC export, and similar to global estimates of the mangrove missing carbon (i.e., ~ 1.9-2.7 g C m-2 d-1). [ABSTRACT FROM AUTHOR]

We demonstrate subnanometer resolution cryo-TEM imaging of smectic layers in the smectic and nematic phases of two bent-core liquid crystals. Our results show perfect periodicity over several hundred layers in the smectic phase and also provide the first direct evidence of smectic clusters on length scales of 30-50 nm in a nematic liquid crystal. The results are corroborated with small angle x-ray scattering measurements. The observation of smectic clusters in the nematic phase is of special interest in bent-core liquid crystals, where the smectic clusters are stable over wide temperature ranges, in contrast to the well-known pretransitional "cybotactic" clusters that appear only in the vicinity of a bulk smectic phase. The means to characterize and manipulate this nanoscale molecular order could open up completely new liquid crystal-based technologies. [ABSTRACT FROM AUTHOR]

We report on a series of measurements on the microscopic structure and the magneto-optical properties of a calamitic liquid crystalline compound in its nematic phase. Structural studies show the existence of short-range, tilted smectic order consistent with pretransitional effects above an underlying smectic phase. Concomitantly, magneto-optical results exhibit the existence of an optic axis not collinear with the uniaxial director. This apparent biaxial nature is discussed within the context of coupling between the tensor nematic and the smectic order parameters. [ABSTRACT FROM AUTHOR]

Using a magnetic Frederiks transition technique, we measured the temperature and concentration dependences of splay K1, twist K2, and bend K3 elastic constants for the lyotropic chromonic liquid crystal (LCLC) Sunset Yellow, formed through non-covalent reversible aggregation of organic molecules in water. K1 and K3 are comparable to each other and are an order of magnitude higher than K2. At higher concentrations and lower temperatures, K1 and the ratios K1/K3, K1/K2 increase, which is attributed to elongation of self-assembled LCLC aggregates, a feature not found in conventional thermotropic and lyotropic liquid crystals formed by covalently bound units of a ?xed length. [ABSTRACT FROM AUTHOR]

Using a magnetic Frederiks transition technique, we measure the temperature and concentration dependences of splay K1, twist K2, and bend K3 elastic constants for the lyotropic chromonic liquid crystal sunset yellow formed through noncovalent reversible aggregation of organic molecules in water. K1 and K3 are comparable to each other and are an order of magnitude higher than K2. At higher concentrations and lower temperatures, K1 and the ratios K1/K3 and K1/K2 increase, which is attributed to elongation of self-assembled lyotropic chromonic liquid crystal aggregates, a feature not found in conventional thermotropic and lyotropic liquid crystals formed by covalently bound units of a fixed length. [ABSTRACT FROM AUTHOR]

We report on homodyne dynamic light scattering measurements of orientational fluctuation modes in both calamitic and bent-core nematic liquid crystals, carried out in the new split-helix resistive magnet at the National High Magnetic Field Laboratory. The relaxation rate and inverse scattered intensity of director fluctuations exhibit a linear dependence on field-squared up to 25 tesla, which is consistent with strictly lowest order coupling of the tensor order parameter Q to field (QαβBαBβ) in the nematic free energy. However, we also observe evidence of field dependence of certain nematic material parameters, an effect which may be expected from the mean field scaling of these quantities with the magnitude of Q and the predicted variation of Q with field. [ABSTRACT FROM AUTHOR]

The effect of director pretilt on the twist magnetic Fréedericksz transition of nematics was investigated in a planar cell. The director configuration was calculated as a function of magnetic inductance. The dielectric and optical response of the nematic liquid crystal was numerically modeled. A dielectric measurement method for determining the elastic constant K22 is presented. The influence of the conditions for the Mauguin effect is discussed. The theoretical predictions were confirmed by our experiments. Experimental data for all elastic constants of a bent-core nematic material are presented and discussed. [ABSTRACT FROM AUTHOR]

The existence of the elusive biaxial phase has been the subject of much discussion since it was predicted by Freiser in 1970. More recently, there have been numerous attempts to find a thermotropic liquid crystal that exhibits a biaxial phase and with this, conflicting reports about whether such a phase has been positively identified in bent-core liquid crystals. One reason for the discrepancy is that there is currently no way to role out surface effects or anchoring transitions, both of which may give a false positive identification of a uniaxial-biaxial nematic transition. We have developed a technique that uses a magnetic field to align the uniaxial director, thus widening its application to any bent-core nematic material. [ABSTRACT FROM AUTHOR]

Using a combination of dynamic light scattering and Freedencksz transitions induced in applied magnetic and electric fields, we have determined the absolute magnitudes of the Frank elastic constants and effective orientational viscosities of the bent-core nematic liquid crystal, 4-chloro-1,3-phenylene bis 4-[4'- (9-decenyloxy)benzoyloxy] benzoate. At a fixed temperature 2 °C below the isotropic-nematic transition, we find K11 = 3.1 × 10-12 N, K22 = 0.31 × l0-12 N, K33 = 0.88 × 10-12 N, ηsplay = 1.1 Pa s, ηtwist = 0.37 Pa s, and ηbend = 1.2 Pa s. The unusual anisotropies of these parameters are discussed in terms of short-range, smectic-C-like correlations among molecules in the nematic phase. [ABSTRACT FROM AUTHOR]

Aim: The aim of the study is to assess the feasibility of whole-body low-dose computed tomography (WBLDCT) in the diagnosis and staging of multiple myeloma and compare to skeletal survey (SS), using bone marrow biopsy and whole-body magnetic resonance imaging (WBMRI; where available) as gold standard.Materials and Methods: Patients referred over an 18-month period for investigation of suspected multiple myeloma or restaging of myeloma were randomized to undergo one of two WBLDCT protocols using high kVp, low mAs technique (140 kVp, 14 mAs; or 140 kVp, 25 mAs). Recent WBMRI scans were reviewed in 23 cases. Each imaging modality was assessed by two radiologists in consensus and scored from 0-3 (0 = normal, 1 = 1-4 lesions, 2 = 5-20 lesions, 3 >or= 20 lesions/diffuse disease) in ten anatomical areas. Overall stage of disease, image quality score, and the degree of confidence of diagnosis were recorded. Diagnostic accuracy of skeletal survey and WBLDCT were determined using a gold standard of bone marrow biopsy and distribution of disease was compared to WBMRI.Results: Thirty-nine patients were evaluated. WBLDCT identified more osteolytic lesions than skeletal survey with a greater degree of diagnostic confidence and led to restaging in 18 instances (16 upstaged, two downstaged). In those with recent WBMRI, distribution of disease on WBLDCT showed superior correlation with WBMRI when compared with SS. Overall reader impression of stage on WBLDCT showed significant correlation with WBMRI (kappa = 0.454, p < 0.05). WBLDCT provided complementary information to WBMRI in nine patients with normal marrow signal following treatment response, but which were shown to have diffuse residual cortical abnormalities on CT.Conclusion: WBLDCT at effective doses lower than previously reported, is superior to SS at detecting osteolytic lesions and at determining overall stage of multiple myeloma, and provides complementary information to WBMRI. [ABSTRACT FROM AUTHOR]

We report on measurements of magnetic field induced nematic order in the bent-core liquid crystal 4-chlororesorcinol bis[4-(4-n dodecyloxybenzoyloxy) benzoate]. Using the 31 Tesla solenoid at the National High Magnetic Field Laboratory, we have observed, at temperatures less than one degree above the clearing point, a first-order transition to the nematic phase. The critical magnetic field at which this occurs increases with temperature. We discuss these results within the context of both Maier-Saupe and Landau-deGennes mean field models for the nematic-isotropic transition. The implications of possible tetrahedratic order are also discusse. To our knowledge, this is the first observation of such a magnetic field-induced transition in a thermotropic liquid crystal; the reasons for which this behavior is now attainable are discussed. [ABSTRACT FROM AUTHOR]

Joubert syndrome-related disorders (JSRDs) are autosomal recessive pleiotropic conditions sharing a peculiar cerebellar and brainstem malformation known as the ‘molar tooth sign’ (MTS). Recently, mutations in a novel ciliary gene, RPGRIP1L, have been shown to cause both JSRDs and Meckel–Gruber syndrome. We searched for RPGRIP1L mutations in 120 patients with proven MTS and phenotypes representative of all JSRD clinical subgroups. Two homozygous mutations, the previously reported p.T615P in exon 15 and the novel c.2268_2269delA in exon 16, were detected in 2 of 16 families with cerebello-renal presentation (∼12%). Conversely, no pathogenic changes were found in patients with other JSRD phenotypes, suggesting that RPGRIP1L mutations are largely confined to the cerebello-renal subgroup, while they overall represent a rare cause of JSRD (<2%). [ABSTRACT FROM AUTHOR]

BackgroundThe ACE project involved 62 participants with a first episode of psychosis randomly assigned to either a cognitive behaviour therapy (CBT) intervention known as Active Cognitive Therapy for Early Psychosis (ACE) or a control condition known as Befriending. The study hypotheses were that: (1) treating participants with ACE in the acute phase would lead to faster reductions in positive and negative symptoms and more rapid improvement in functioning than Befriending; (2) these improvements in symptoms and functioning would be sustained at a 1-year follow-up; and (3) ACE would lead to fewer hospitalizations than Befriending as assessed at the 1-year follow-up.MethodTwo therapists treated the participants across both conditions. Participants could not receive any more than 20 sessions within 14 weeks. Participants were assessed by independent raters on four primary outcome measures of symptoms and functioning: at pretreatment, the middle of treatment, the end of treatment and at 1-year follow-up. An independent pair of raters assessed treatment integrity.ResultsBoth groups improved significantly over time. ACE significantly outperformed Befriending by improving functioning at mid-treatment, but it did not improve positive or negative symptoms. Past the mid-treatment assessment, Befriending caught up with the ACE group and there were no significant differences in any outcome measure and in hospital admissions at follow-up.ConclusionsThere is some preliminary evidence that ACE promotes better early recovery in functioning and this finding needs to be replicated in other independent research centres with larger samples. [ABSTRACT FROM AUTHOR]

BACKGROUND: The ACE project involved 62 participants with a first episode of psychosis randomly assigned to either a cognitive behaviour therapy (CBT) intervention known as Active Cognitive Therapy for Early Psychosis (ACE) or a control condition known as Befriending. The study hypotheses were that: (1) treating participants with ACE in the acute phase would lead to faster reductions in positive and negative symptoms and more rapid improvement in functioning than Befriending; (2) these improvements in symptoms and functioning would be sustained at a 1-year follow-up; and (3) ACE would lead to fewer hospitalizations than Befriending as assessed at the 1-year follow-up.MethodTwo therapists treated the participants across both conditions. Participants could not receive any more than 20 sessions within 14 weeks. Participants were assessed by independent raters on four primary outcome measures of symptoms and functioning: at pretreatment, the middle of treatment, the end of treatment and at 1-year follow-up. An independent pair of raters assessed treatment integrity. RESULTS: Both groups improved significantly over time. ACE significantly outperformed Befriending by improving functioning at mid-treatment, but it did not improve positive or negative symptoms. Past the mid-treatment assessment, Befriending caught up with the ACE group and there were no significant differences in any outcome measure and in hospital admissions at follow-up. CONCLUSIONS: There is some preliminary evidence that ACE promotes better early recovery in functioning and this finding needs to be replicated in other independent research centres with larger samples. [ABSTRACT FROM AUTHOR]

Random variability in product thermal properties combined with non-uniformity in the process environment can cause a distribution in product temperature at the end of a heating stage. This unwanted dispersion can affect the integrity and profitability of the operation. The dispersion can be quantified with the statistics of range, minimum or variance. This paper demonstrates how the magnitude of this dispersion is sensitive to the level of processing temperature that is employed. It explains and gives a criterion by which the process environment can be judged as being either uniform or non-uniform. Furthermore the paper demonstrates that using a certain processing time will minimize the variance in product temperature. Using a case study, involving the heat treatment of foods, the strategies that can be employed to control product temperature dispersion, through selection of the process temperature, are outlined. [ABSTRACT FROM AUTHOR]

Abstract: Average in-field water application efficiency in furrow-irrigated cotton (Gossypium hirsutum L.) in Australia is less than optimal, and The underlying reasons may include surface sealing, exposure of sodic soil by laser levelling, and soil compaction due to wheel-trafficking. The objective of this study was to quantify the effects of reducing traffic and tillage intensity on furrow soil properties in an irrigated Vertisol. Soil was sampled during the growing seasons of 2001–02, 2003–04 and 2005–06 from the surface 50-mm of adjacent wheel-tracked and non-wheel-tracked furrows in an experiment in north-western New South Wales, Australia. The treatments were: cotton sown either after conventional tillage (disc-ploughing and incorporating cotton stalks to 0.2m, chisel ploughing to 0.3m followed by bed construction) or on “permanent beds” (slashing cotton plants after harvest, followed by root cutting and bed renovation with a disc-hiller). Irrigation water was alkaline but had low salinity and sodium adsorption ratio. Soil properties measured were pH, EC1:5, geometric mean diameter (GMD) and specific volume (SV) of dry soil aggregates, exchangeable cations and plastic limit. Permanent bed systems had generally lower pH and higher SOC than conventionally tilled furrows, although differences were small. Soil pH and SOC averaged over the three growing seasons was 6.9 and 0.89g/100g, respectively, in permanent bed furrows, and 7.1 and 0.84g/100g, respectively, in conventionally tilled furrows. Compared to non-wheel-tracked furrows, plastic limit was lower (0.24 vs. 0.25g/g), and EC1:5 (0.24 vs. 0.20dS/m) and GMD (2.6 vs. 2.1mm) higher in wheel-tracked furrows. Intra-seasonal changes in soil properties of furrows were also small, and are unlikely to significantly affect any hydrological processes. Inter-seasonal differences were, however, significant, and could affect hydrological processes in this soil. [Copyright &y& Elsevier]

We report a set of material characterizations on the nematic mixture Mischung V. With these measurements, as well as previously known results, Mischung V becomes the second nematic liquid crystal possessing a complete set of known physical parameters relevant for electroconvection, enabling quantitative comparison with theoretical predictions to be made. Additionally, we have identified a stable dopant which induces in Mischung V the electrical conductivity necessary for observing the conduction regime of electroconvection. Mischung V is thus validated as a suitable substitute for materials that have traditionally been chosen for these types of experiments. However, Mischung V does not present the same experimental difficulties as traditional materials. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented concerning the fatty acid 2-hydroxylase (FA2H) gene mutation in three Arab families which developed neurodegeneration and hereditary spastic paraparesis.

Recently ferroelectric ceramic and bent-core nematic liquid crystals have demonstrated flexoelectricity (coupling between curvature strains to electric polarization) up to 104 times larger than the previous standards. This may allow for usable electromechanical devices. However, ceramics are too rigid to withstand large bending and bent-core nematic fluids must be physically supported—their technological applicability is still limited. In this paper, we show that novel side-chain bent-core nematic elastomers not only produce giant flexoelectricity but are also robust and flexible enough for microscale parasitic power generation. [ABSTRACT FROM AUTHOR]

Evaluates a randomized trial of proximal gastric vagotomy (PGV) with or without pyloroplasty in the treatment of uncomplicated duodenal ulcer. Dominance of the PGV; Likeliness of preoperative peak acid output to develop recurrent ulceration; Effects of the combination of pyloroplasty with PGV.

We present studies of chiral nematic liquid crystals composed of flexible dimer molecules subject to large dc magnetic fields between 0 and 31 T. We observe that these fields lead to selective reflection of light depending on temperature and magnetic field. The band of reflected wavelengths can be tuned from ultraviolet to beyond the IR-C band. A similar effect induced by electric fields has been presented previously, and was explained by a field-induced oblique-heliconical director deformation in accordance with early theoretical predictions. The use of magnetic field here instead of electric field allows precise measurements of some material constants and holds promise for wireless tuning of selective reflection. [ABSTRACT FROM AUTHOR]

We have determined the nematic-isotropic transition temperature as a function of an applied magnetic field in three different thermotropic liquid crystalline dimers. These molecules are comprised of two rigid calamitic moieties joined end to end by flexible spacers with odd numbers of methylene groups. They show an unprecedented magnetic field enhancement of nematic order in that the transition temperature is increased by up to 15 K when subjected to a 22 T magnetic field. The increase is conjectured to be caused by a magnetic-field-induced decrease of the average bend angle in the aliphatic spacers connecting the rigid mesogenic units of the dimers. [ABSTRACT FROM AUTHOR]

Despite its common association with viral illnesses, intussusception has only rarely been found in the presence of bacterial infections. Two infants are described, both of whom were admitted to hospital with bilious vomiting, drowsiness, and dehydration. Both infants required urgent intravenous volume expansion. Intussusception was confirmed, and reduction was achieved by enema in both cases. Recovery was slow, and one infant developed a seizure. Evidence of meningococcal meningitis was found in both, with septicaemia in one. Neurological outcome is normal to date, and there has been no recurrence of intussusception in either case. [ABSTRACT FROM AUTHOR]