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Generalizations of the Sweedler dual
No full textAs left adjoint to the dual algebra functor, Sweedler’s finite dual construction is an important tool in the theory of Hopf algebras over a field. We show in this note that the left adjoint to the dual algebra functor, which exists over arbitrary rings, shares a number of properties with the finite dual. Nonetheless the requirement that it should map Hopf algebras to Hopf algebras needs the extra assumption that this left adjoint should map an algebra into its linear dual. We identify a condition guaranteeing that Sweedler’s construction works when generalized to noetherian commutative rings. We establish the following two apparently previously unnoticed dual adjunctions: For every commutative ring R the left adjoint of the dual algebra functor on the category of R-bialgebras has a right adjoint. This dual adjunction can be restricted to a dual adjunction on the category of Hopf R-algebras, provided that R is noetherian and absolutely flat.29 page(s
Simple composite right/left-handed leaky-wave antennas for continuous beam scanning from backward to forward direction
No full textMicrostrip leaky-wave antennas (MLWAs) are presented for continuous beam scanning from backward to forward directions. The antenna is implemented by cascading composite right/left-handed (CRLH) unit cells. Each unit cell consists of two outer shorted patches and an open patch between the shorted patches. Series capacitance is implemented by using gaps between the patches, and shunt inductance is achieved by using metallic vias. Two antennas with different numbers of unit cells are considered for the analysis. An antenna with 8 unit cells covers an impedance bandwidth from 6.12 to 9.075 GHz and the main beam scans continuously from -52° to 47° when the frequency is swept from 6.25 to 9.25 GHz.3 page(s
New insights into Brunner syndrome and potential for targeted therapy
No full textWe report two families with Brunner syndrome living in one state of Australia. The first family had a predicted protein-truncating variant of monoamine oxidase A (MAOA) (p.S251KfsX2). Affected males had mild intellectual disability (ID), obsessive behaviour, limited friendships and were introverted and placid during clinical interview. The family disclosed episodic explosive aggression after a diagnosis was made. The second family had a missense variant in MAOA (p.R45W). Affected males had borderline-mild ID, attention deficit disorder and limited friendships. One had a history of explosive aggression in childhood and episodic symptoms of flushing, headaches and diarrhoea. Their carrier mother had normal intelligence but similar episodic symptoms. Characteristic biochemical abnormalities included high serum serotonin and urinary metanephrines and low urinary 5-hydroxyindoleacetic acid (5-HIAA) and vanillylmandelic acid (VMA). Symptomatic individuals in the second family had particularly high serotonin levels, and treatment with a serotonin reuptake inhibitor and dietary modification resulted in reversal of biochemical abnormalities, reduction of ‘serotonergic’ symptoms and behavioural improvement. Brunner syndrome should be considered as a cause of mild ID with paroxysmal behavioural symptoms. It can be screened for with serum/urine metanephrine and serotonin measurement. Cautious treatment with a serotonin reuptake inhibitor, dietary modifications and avoidance of medications contraindicated in patients on monoamine oxidase inhibitors can improve symptoms.8 page(s
The Association between the use of management accounting practices with organizational change and organizational performance
No full textPurpose - This study examines the association between the use of a package of contemporary and a package of traditional management accounting practices with organizational change and organizational performance. Methodology/approach - Data were collected based on a mail survey distributed to a sample of 740 public sector organizations. Findings - The findings indicate that while the prevalence of traditional practices is still dominant, such practices were not associated with organizational change or performance. Rather, those organizations that use contemporary management accounting practices to a greater extent experienced greater change and stronger performance. Practical implications - The findings suggest that contemporary management accounting practices can assist public sector practitioners in improving performance and promoting organizational change. Originality/value - The study provides an empirical insight into the use and effectiveness of management accounting practices in the public sector. The study provides the first empirical analysis of the effect of using a package of management accounting practices in the public sector.32 page(s
Recycling of ancient subduction-modified mantle domains in the Purang ophiolite (southwestern Tibet)
No full textOphiolites in the Indus–Yarlung Zangbo (IYZ) suture (southern Tibet) have been interpreted as remnants of the Neo-Tethyan lithosphere. However, the discovery of diamonds and super-reducing, ultra-high pressure (SuR-UHP) mineral assemblages (e.g., coesite after stishovite, olivine after wadsleyite, native metals, alloys, and moissanite) in some of these massifs and associated chromitites requires a re-evaluation of their origin and evolution. A new petrological and geochemical study of the Purang ophiolite in the western IYZ suture sheds new lights on these issues. The depleted harzburgites of the Purang massif have low modal contents of clinopyroxene ( 40 ~ 70) and pyroxenes (> 16 in orthopyroxene, and > 20 in clinopyroxene), suggesting high degrees of melt extraction (> 20%). These features are not consistent with formation in a (ultra-) slow-spreading mid-ocean ridge. These peridotites have high modal contents of orthopyroxene; this, and the extremely high Cr# of spinels in these peridotites, suggests modification in a subduction zone. The clinopyroxene-rich harzburgites and lherzolites contain rare spinel–pyroxene symplectites after garnet. Their clinopyroxenes have low MREE-to-HREE ratios ((Sm/Yb)N < 0.1) at relatively high HREE concentrations, and are Na-rich but Nd-poor. The relatively enrichment of Na but depletion of Nd in clinopyroxene cannot be explained by refertilization with MORB melts but are consistent with an origin from Na-rich subcontinental lithospheric mantle (SCLM). All lines of evidence suggest that these peridotites underwent initial melting in the stability field of garnet–facies peridotites, followed by additional melting in the spinel–facies mantle. Whole-rock Os isotopic compositions of the Purang peridotites give ancient TRD model ages (up to 1.3 Ga), indicating that the formation of these ancient depletion residues predated the opening of Neo-Tethyan Ocean. These observations, together with recent studies on other IYZ peridotites, suggest that the Purang peridotites are genetically unrelated to the associated mafic crust. Instead, they represent ancient SCLM domains, initially formed beneath a continental margin, and then modified by subduction, before they were incorporated into the Neo-Tethyan ocean basin. This model is consistent with the deep-mantle-recycling model for the presence of SuR-UHP phases in the IYZ ophiolites. The infiltration of MORB melts through these ancient depleted peridotites during their final exhumation in a (ultra-) slow-spreading center may have refertilized them to produce the clinopyroxene-rich peridotites.16 page(s
Educating patients about Internet-delivered cognitive behaviour therapy : perceptions among treatment seekers and non-treatment seekers before and after viewing an educational video
No full textInternet-delivered cognitive behaviour therapy (ICBT) is an efficacious, yet novel approach to the treatment of depression and anxiety. It has the potential to improve access to evidenced-based care, but only if potential patients are aware of, understand, and have positive expectations about this treatment. In order to establish whether the use of an educational video could improve favourable expectations of ICBT, two studies were conducted. The goal of the first study was to determine whether an educational video would improve perceptions of ICBT among individuals seeking ICBT treatment and to determine what type of information (client testimonials versus statistical information related to outcomes) facilitates the greatest increase in positive expectations of ICBT. Participants who visited an ICBT service (N = 71) website were invited to first complete brief questionnaires assessing initial perceptions of ICBT. They were then randomly assigned to watch one of two videos containing either client testimonials (n = 32) or statistical information related to outcomes (n = 39). Patient perceptions of ICBT were then reassessed. Perceptions of ICBT were significantly higher post-video than pre-video and the type of information did not impact perceptions of ICBT. In the second study, the research was extended by examining perceptions of ICBT before and after watching an educational video (including both statistical and narrative information as this had no impact on perceptions) in a sample of individuals (N = 94) who were experiencing anxiety and depression but were not specifically seeking ICBT. As with treatment seekers, perceptions of ICBT were significantly higher post-video than pre-video. Comparison of the treatment and non-treatment seekers revealed no differences in perceptions of ICBT between the samples. The findings suggest that educational videos are an effective way to increase expectations of ICBT. Future directions for research are described.7 page(s
Socio-economic vulnerability to climate change in the central mountainous region of eastern Mexico
No full textClimate change effects are expected to be more severe for some segments of society than others. In Mexico, climate variability associated with climate change has important socio-economic and environmental impacts. From the central mountainous region of eastern Veracruz, Mexico, we analyzed data of total annual precipitation and mean annual temperature from 26 meteorological stations (1922–2008) and from General Circulation Models. We developed climate change scenarios based on the observed trends with projections to 2025, 2050, 2075, and 2100, finding considerable local climate changes with reductions in precipitation of over 700 mm and increases in temperature of ~9°C for the year 2100. Deforested areas located at windward were considered more vulnerable, representing potential risk for natural environments, local communities, and the main crops cultivated (sugarcane, coffee, and corn). Socio-economic vulnerability is exacerbated in areas where temperature increases and precipitation decreases.15 page(s
Terror mismanagement : evidence that mortality salience exacerbates attentional bias in social anxiety
No full textDeath anxiety is a basic fear underlying a range of psychological conditions, and has been found to increase avoidance in social anxiety. Given that attentional bias is a core feature of social anxiety, the aim of the present study was to examine the impact of mortality salience (MS) on attentional bias in social anxiety. Participants were 36 socially anxious and 37 non-socially anxious individuals, randomly allocated to a MS or control condition. An eye-tracking procedure assessed initial bias towards, and late-stage avoidance of, socially threatening facial expressions. As predicted, socially anxious participants in the MS condition demonstrated significantly more initial bias to social threat than non-socially anxious participants in the MS condition and socially anxious participants in the control condition. However, this effect was not found for late-stage avoidance of social threat. These findings suggest that reminders of death may heighten initial vigilance towards social threat.10 page(s
Educator talk in long day care nurseries : how context shapes meaning
No full textLittle is known about the quality and characteristics of the language used by childcare staff when interacting with infants in non-parental group care settings. This qualitative study analysed the manner in which staff used language when interacting with ten children aged between 9 and 20 months in four different long day care centres in Sydney, Australia. Each infant was audiorecorded for one whole day using a small recording device attached to her/his clothing, which captured all the language spoken directly to, or in their presence of, the infant. The infants and staff were simultaneously videorecorded as they went about their everyday activities, to provide additional contextual information. Using systemic functional linguistics as the theoretical underpinning, the study found that staff members tended to talk to more than one child at a time, limiting their potential to engage in the types of sustained conversations with individual children that have been shown to promote language development. Staff also tended to use language primarily to manage children’s behaviour and provide physical care, rather than using language to encourage children to use their own developing language to represent their experiences in a variety of contexts. The findings have implications for group size, early childhood teacher education and inservice professional development.10 page(s
Perturbed connectivity of the amygdala and its subregions with the central executive and default mode networks in chronic pain
No full textMaladaptive responses to pain-related distress, such as pain catastrophizing, amplify the impairments associated with chronic pain. Many of these aspects of chronic pain are similar to affective distress in clinical anxiety disorders. In light of the role of the amygdala in pain and affective distress, disruption of amygdalar functional connectivity in anxiety states, and its implication in the response to noxious stimuli, we investigated amygdala functional connectivity in 17 patients with chronic low back pain and 17 healthy comparison subjects, with respect to normal targets of amygdala subregions (basolateral vs centromedial nuclei), and connectivity to large-scale cognitive-emotional networks, including the default mode network, central executive network, and salience network. We found that patients with chronic pain had exaggerated and abnormal amygdala connectivity with central executive network, which was most exaggerated in patients with the greatest pain catastrophizing. We also found that the normally basolateral-predominant amygdala connectivity to the default mode network was blunted in patients with chronic pain. Our results therefore highlight the importance of the amygdala and its network-level interaction with large-scale cognitive/affective cortical networks in chronic pain, and help link the neurobiological mechanisms of cognitive theories for pain with other clinical states of affective distress.9 page(s