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A Quasi-randomized feasibility pilot study of specific treatments to improve emotion recognition and mental-state reasoning impairments in schizophrenia
No full textBACKGROUND: Impaired ability to make inferences about what another person might think or feel (i.e., social cognition impairment) is recognised as a core feature of schizophrenia and a key determinant of the poor social functioning that characterizes this illness. The development of treatments to target social cognitive impairments as a causal factor of impaired functioning in schizophrenia is of high priority. In this study, we investigated the acceptability, feasibility, and limited efficacy of 2 programs targeted at specific domains of social cognition in schizophrenia: "SoCog" Mental-State Reasoning Training (SoCog-MSRT) and "SoCog" Emotion Recognition Training (SoCog-ERT). METHOD: Thirty-one participants with schizophrenia or schizoaffective disorder were allocated to either SoCog-MSRT (n = 19) or SoCog-ERT (n = 12). Treatment comprised 12 twice-weekly sessions for 6 weeks. Participants underwent assessments of social cognition, neurocognition and symptoms at baseline, post-training and 3-months after completing training. RESULTS: Attendance at training sessions was high with an average of 89.29 % attendance in the SoCog-MSRT groups and 85.42 % in the SoCog-ERT groups. Participants also reported the 2 programs as enjoyable and beneficial. Both SoCog-MSRT and SoCog-ERT groups showed increased scores on a false belief reasoning task and the Reading the Mind in the Eyes test. The SoCog-MSRT group also showed reduced personalising attributional biases in a small number of participants, while the SoCog-ERT group showed improved emotion recognition. CONCLUSIONS: The results are promising and support the feasibility and acceptability of the 2 SoCog programs as well as limited efficacy to improve social cognitive abilities in schizophrenia. There is also some evidence that skills for the recognition of basic facial expressions need specific training. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12613000978763 . Retrospectively registered 3/09/2013.15 page(s
Quantitative metabolome profiling reveals the involvement of the kynurenine pathway in influenza-associated encephalopathy
No full textIntroduction: Influenza-associated encephalopathy is a serious complication of influenza and is the most common form of acute encephalitis/encephalopathy in Japan. The number of reports from other countries is increasing, reflecting international recognition and concern. Objectives: Identification of a specific biomarker could provide important clues about the pathophysiology of influenza-associated encephalopathy. Methods: During the 2009–2011 flu seasons, 34 pediatric patients hospitalized with influenza complications, including influenza-associated encephalopathy, were enrolled in the study. Serum samples were collected during the acute and convalescent phases of disease. Patients were classified into encephalopathy (n = 12) and non-encephalopathy (n = 22) groups. Serum metabolites were identified and quantified by capillary electrophoresis coupled with time-of-flight mass spectrometry. Quantified data were evaluated for comparative analysis. Subsequently, a total of 55 patients with or without encephalopathy were enrolled for absolute quantification of serum kynurenine and quinolinic acid. Results: Based on m/z values and migration times, 136 metabolites were identified in serum samples. During the acute phase of disease, three metabolites (succinic acid, undecanoic acid, and kynurenine) were significantly higher, and two other metabolites (decanoic acid and cystine) were significantly lower, in the encephalopathy group compared to the non-encephalopathy group (p = 0.012, 0.022, 0.044, 0.038, 0.046, respectively). In a larger patient group, serum kynurenine and its downstream product in tryptophan metabolism, quinolinic acid, a known neurotoxin, were significantly higher in the encephalopathy than the non-encephalopathy without febrile seizure group. Conclusion: Comprehensive metabolite profiles revealed five metabolites as potential biomarkers for influenza-associated encephalopathy; the tryptophan–kynurenine metabolic process could be associated with its pathophysiology.9 page(s
Cerebral hemodynamics and the role of transcranial Doppler applications in the assessment and management of cerebral arteriovenous malformations
No full textDramatic hemodynamic changes occur following resection of brain arteriovenous malformations (AVM). Transcranial Doppler (TCD) records non-invasive velocity and pulsatility parameters. We undertook a systematic review to assess AVM hemodynamics including the time course of changes in velocity and pulsatility in patients undergoing AVM resection. The review employed the Embase and Medline databases. A search strategy was designed. An initial title search for clinical series on AVM and TCD was performed followed by a search for reports on AVM and TCD. A total of 283 publications were selected. Full text analysis produced 54 studies with extractable data regarding AVM, velocity and pulsatility. Two TCD techniques were utilized: conventional "blind" TCD (blind TCD); and transcranial color duplex Doppler (TCCD). Of these, 23 publications reported on blind TCD and seven on TCCD. The presence of high velocity and low pulsatility within AVM feeding arteries preoperatively followed by a postoperative decrease in velocity and subsequent increase in pulsatility of feeding arteries is established. The time sequence of hemodynamic changes following AVM resection using TCD remains uncertain, confounded by variations in methodology and timing of perioperative measurements. Of the two techniques, TCCD reported qualitative aspects including improved differentiation of feeding arteries from draining veins. However, there are a limited number of studies supporting this conclusion. Furthermore, none report reproducible changes with time from treatment. TCCD appears to be a useful technique to analyze the hemodynamic changes occurring following treatment of AVM, however little data is available. This is a field of research that is appropriate to pursue.7 page(s
Novel nanomaterial-based saturable absorbers for ultrashort-pulsed mid-infrared waveguide chip lasers
No full textMode-locked integrated mid-IR waveguide chip lasers with ultra-short pulse duration and high peak power are of great interest for a large range of applications like trace-gas spectroscopy and early-cancer detection. As those lasers are automatically embedded within a small block of doped glass, they are inherently robust and immune to environmental fluctuations. In this paper we investigate the suitability of various novel nanomaterials for the realisation of saturable absorbers for passive mode locking of femtosecond laser-written mid-infrared waveguide lasers. We compare and characterise saturable absorbers based on carbon nanotubes, graphene, topological insulators, transition metal dichalcogenides as well as black phosphorus and analyse their performance in a thulium-doped waveguide laser operating around 2 micron.3 page(s
Unpredictability and complexity of print-to-speech correspondences increase reliance on lexical processes: more evidence for the orthographic depth hypothesis
No full textThe Orthographic Depth Hypothesis [Katz, L., & Frost, R. (1992). The reading process is different for different orthographies: The orthographic depth hypothesis. In R. Frost & L. Katz (Eds.), Orthography, phonology, morphology, and meaning (pp. 67–84). Amsterdam: Elsevier Science] proposes cross-linguistic differences in the involvement of lexical processing during reading. In orthographies with complex, inconsistent, and/or incomplete sublexical correspondences, decoding is more difficult and therefore slower. This gives more time to the lexical route to retrieve information, and leads to a greater ratio of lexical processing. We test whether this mechanism applies both for words with inconsistent (in English) and for words with complex (in French) correspondences. As complex correspondences are sufficient to derive a correct pronunciation, an increase in lexical processing may not occur. In a reading-aloud task, we used the frequency effect to measure lexical processing. The data showed stronger involvement of lexical processing for inconsistent compared to consistent words, and for complex compared to simple words. The results confirm that Katz and Frost’s proposed mechanism applies to different sources of orthographic depth.15 page(s
Floral nectar : pollinator attraction or manipulation?
No full textThe literature suggests that floral nectar acts principally to attract pollinator visitation (and/or revisitation), thereby enhancing plant reproductive success. However, floral nectar also manipulates pollinator behaviour during and immediately following plant visits, affecting pollen transfer, and plant reproduction. I argue that floral nectar should really be viewed as a pollinator manipulant rather than attractant, thus potentially explaining why its concentration is not generally high and why it decreases with increasing pollinator body size. Otherwise, such patterns may remain mysterious and unexplained.3 page(s
Professional associations, accreditation and higher education : foundations for future relations
No full text14 page(s
The four elements of ecocinema
No full textTheoretical thesis.Bibliography: pages 80-91.Introduction : ecological thinking -- Chapter 1. Thinking about the world : a question of the elements -- Chapter 2. Shorelines of spectatorship : cinematic engagement and the filmworld's elemental landscape -- Chapter 3. From element to elemental : ecocinema and ecological thinking -- Conclusion.In the context of ecocinema theory and phenomenological aesthetics, this cross-disciplinary thesis is the first that proposes a film theory of the four natural elements – earth, air, water and fire. Much like Pre-Socratic cosmogony, these four natural elements are the basic material to create almost any film world. Thinking through earth, air, water and fire in film – be it 1960 art house cinema or the newest CGI-loaded blockbuster – reveals forgotten philosophical meaning and the essential role the natural elements play in imagining the world.Drawing on phenomenological and aesthetic theories of cinematic experience, this new way of thinking these elements through film involves a threefold exploration. First, it investigates how the elements matter on this most fundamental level – how they help creating an expressive film world that engages the spectator on a phenomenological level of experience.Secondly, it considers how the explicit depiction of earth, air, water and/or fire is meaningful before its narrative-symbolical significance: in the phenomenological film experience, cinema’s ‘elemental images’ are directly experienced as very concrete manifestations of the film world’s materiality. This, thirdly, opens up a new sensitivity to the environment: in short, my claim is that all films have this ecological potential; it is actually intrinsic to cinema’s technological nature that the spectator may experience an original relation to the natural world.Mode of access: World wide web1 online resource (91 pages
Comparison of techniques to reconstruct palaeoclimates of China
No full textThis thesis was prepared under a co-tutelle program between Macquarie University and State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, the Chinese Academy of Sciences.Bibliography: pages 126-160.1. Introduction -- 2. Evaluation of the realism of climate reconstruction using the coexistence approach with modern pollen samples from the Qinghai-Tibetan Plateau -- 3. Relationships between leaf morphometric traits and climate -- 4. Reconstruction of Eocene, Miocene and Pliocene climates in China using plant morphometric traits -- 5. Conclusions -- Appendices.Investigating the past climate is helpful to distinguish humankind’s contribution on presentclimate change, and also helpful to understand the historic or geological evolution of global environmental conditions. A number of different types of records provide information about past climate changes, including petrology, sedimentology, glaciology, dendrochronology, palynology and others. Various different techniques can be used to make quantitative reconstructions from palaeodata. All of these methods have their shortcomings and advantages. In this thesis, I examine two reconstruction methods, which have been widely applied to make reconstructions of climate during pre-Quaternary times, specifically the coexistence approach and leaf traits analysis.The coexistence approach (CoA) assumes that the climate of a fossil assemblage can be defined from the overlap between the climate ranges of the individual taxa, where the climate range of each taxon is defined by the climate range under which it grows today. For taxa that are no longer extant, the range is defined as that of the nearest living relative (NLR). The method assumes that it is possible to define the modern climate tolerance accurately and also that taxa were physically present at the site. In Chapter 2, I test the impact of these two assumptions on CoA reconstructions of mean annual precipitation (MAP), mean annual temperature (MAT), mean temperature of the warmest month (MTWA) and mean temperature of the coldest month (MTCO) using modern pollen data from the Qinghai-Tibetan Plateau. I find that the data quality of NLRs and the exotic pollen seriously affect the reconstructed MAP, MAT, MTWA and MTCO. The uncertainties are also relatively large, especially for those three temperature parameters, even those two factors considered. Thus the complementary method should be explored.Methods based on the correlation between leaf physiognomy and climate variables provide an alternative approach to reconstructing past climate. The two most widely used methods are like leaf margin analysis (LMA) and the climate leaf analysis multivariate program (CLAMP). The disadvantages of these methods are identified in various studies, such as using the limited leaf traits and the problem of correlation within traits. Hence, we are exploring our leaf traits-climate model method.I first establish the modern relationships between leaf traits and climates (Chapter 3) based on a large data set of modern trait observations from China. I used logistic regression techniques to investigate the relationships between summer temperature (measured by the accumulated temperature sum above 0°C), plant-available moisture (measured by the ratio of actual to equilibrium transpiration) and seasonality (measured by the daily mean growing season temperature when temperatures are >5°C) and the frequencies of 25 leaf morphometric traits, collected from 98 sites sampling the range of climate and vegetation types found in China. Results show that these morphometric traits vary along climate gradients in a predictable and understandable way. Different traits combination can outline the specific climate space. Leaf traits responding to one or more climate variables indicate that traits could play multiple functions on the adaptation for the moisture and temperature. Many specific relationships between traits and bioclimate variables are conservative across all woody life forms. These findings lay a stronger foundation for using morphometric traits to reconstruct past climates.In Chapter 4, I apply the independent relationships between specific leaf traits and individual climate variables to build predictive models for estimating the length of the growing season (GDD0: growing degree days above a baseline of 0°C) and plant-available moisture (α: the ratio of actual to equilibrium evapotranspiration). I then apply these models to predict the paleoclimate of four fossil leaf floras: from the Fushun Basin (Eocene), from Shanwang Basin (Middle Miocene), from Xiaolongtan Basin (Late Miocene), and from Shengzhou (Pliocene) in China. These geological times are examples of climate intervals when CO₂ was higher than today, and as such provide opportunities to examine how the climate system has responded to enhanced greenhouse gas concentrations. Results show that our models have relatively small reconstruction biases under modern conditions. The reconstructed paleoclimates by the modified models are comparable with previous reconstructions, but our results show more constraints rather than large uncertainties like previous reconstructions. Paleoclimate changes for these four sites are consistent with the evolution of climates in this region and compatible with enhanced monsoon conditions during these high CO₂ intervals.In summary, my thesis makes three important contributions to the field of palaeoclimate reconstruction. Firstly, by quantifying the impact of extra-local pollen on climate reconstructions for the Tibetan Plateau, I demonstrate the unreliability of the coexistence approach when applied in open vegetation. This work suggests that the coexistence approach should only be used when pollen samples can be combined with e.g. macrofossil evidence that would demonstrate the local presence of individual species. Secondly, through applying generalised linear modelling (GLM) technique to establish the independent relationships between multiple climate variables and leaf morphometric traits, after removing the influence of interactions between these variables, I have shown why univariate correlations as used in standard methods such as leaf margin analysis (LMA) and the climate leaf analysis multivariate program (CLAMP) are noisy and unreliable. The GLM methodology provides a better way to use leaf traits to reconstruct climate. Finally, I have developed a new multi-model technique based on these independent trait-climate relationships to reconstruct palaeoclimates in China from fossil leaf floras, and demonstrated that this provides well-constrained estimates of temperature and moisture variables.Mode of access: World wide web1 online resource (xii, 160 pages) map
Cellular pathogenic mechanisms linked to TBK-1 and optineurin in amyotrophic lateral sclerosis
No full textBibliography: pages 102-110.1. Introduction -- 2. Thesis topic -- 3. Materials and methods -- 4. Results -- 5. Discussion.Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease associated with the loss of both upper and lower motor neurons in the motor cortex, brain stem and spinal cord. The pathogenic mechanisms underlying ALS remaln largely unknown. The pathological hallmark of ALS is the presence of cytoplasmic inclusions containing misfolded proteins in degenerating motor neurons. These inclusions are present regardless of the site of symptom onset. age or gender of the patient. Moreover, these inclusions are present in both sporadic and familial forms of ALS. Misfolded protein accumulation triggers stress in the endoplasmic reticulum (ER), inducing the unfolded protein response (UPR), and ER stress is now a well described feature of ALS. The UPR aims to restore proteostasis, but if unresolved triggers apoptosis. The UPR is also linked to autophagy, a self- degradative process that could clear protein aggregates. However. the presence of protein Inclusions suggests that both UPR and autophagy could be dysfunctional in ALS. One of the genes most recently identified In ALS encoded, TBK-1, a kinase involved in different forms of selective autophagy including mitophagy and xenophagy. Interestingly, TBK-1 phosphorylates optienurin an autophagy adaptor protein that is also linked genetically to ALS. In this project the effect of ALS-causing mutations in TBK1 on ER-stress, autophagy and the association between optienurin and TBK-1 autophagy were examined. Using site directed mutagenesis kinase and substrate binding deficient ALS·mutant TBK·1 overexpresslng constructs were generated and the effect of expression of the mutants was examined. Preliminary results showed that expresslon of kinase deficient mutants decreased expression of CHOP, a pro-apoptotic transcription factor, normally induced during ER-stress. This suggests that the kinase activity ofTBK-1 is associated with CHOP independent of ALS. Furthermore. a slight but significantly decrease In LC3-11 levels was detected upon ALS·mutant TBK-1 overexpresslon, suggesting AlS-mutants inhibit autophagy. Additionally, ALS-mutant optineurin failed to recruit endogenous TBK-1 to autophagosomes In NSC-34 cells. This thesis therefore provides novel insight into cellular pathways perturbed in ALS· associated mutants of TBK·1.Mode of access: World wide web1 online resource (xx, 110 pages) illustration