Infrared luminosities of galaxies in the Local Volume

Near-infrared properties of 451 galaxies with distances D \leq 10 Mpc are considered basing on the all-sky two micron survey (2MASS). A luminosity function of the galaxies in the K-band is derived within [-25,-11] mag. The local (D < 8 Mpc) luminosity density is estimated to be 6.8*10^8 L_sun/Mpc^3 that exceeds (1.5+-0.1) times the global cosmic density in the K-band. Virial mass-to-K-luminosity ratios are determined for nearby groups and clusters. In the luminosity range of (5*10^{10} - 2*10^{13})L_sun, the groups and clusters follow the relation \lg(M/L_K) propto (0.27+-0.03) lg(L_K) with a scatter of \~0.1 comparable to errors of the observables. The mean ratio ~= (20-25) M_sun/L_sun for the galaxy systems turns out to be significantly lower than the global ratio, (80-90)M_sun/L_sun, expected in the standard cosmological model with the matter density of Omega_m =0.27. This discrepancy can be resolved if most of dark matter in the universe is not associated with galaxies and their systems.Comment: 15 pages, 7 figures. Astronomy Letters, submitte

A healthy start : promoting mental health and well-being in the early primary school years

This study was in part funded by the University of Malta.Mental health problems in children represent a significant international health concern, with up to one in five children using mental health services during the course of any given year. Identifying the processes of what prevents social, emotional and behaviour difficulties (SEBD) and promotes healthy development from an early age can make a significant contribution to the promotion of positive mental health in children. This article describes a longitudinal study which sought to identify the risk and promotive factors as young children move from the early to junior years in primary school. Multilevel analysis was used to identify the individual, classroom, school, home and community factors that predict change in SEBD and in prosocial behaviour in the early school years. It also calculated the cumulative effect of the various risk and promotive factors on the pupils’ well-being and mental health. The article presents the windows of vulnerability and opportunity for young children’s healthy development, proposing a trajectory for healthy development in early and middle childhood.peer-reviewe

A pedestrian's view on interacting particle systems, KPZ universality, and random matrices

These notes are based on lectures delivered by the authors at a Langeoog seminar of SFB/TR12 "Symmetries and universality in mesoscopic systems" to a mixed audience of mathematicians and theoretical physicists. After a brief outline of the basic physical concepts of equilibrium and nonequilibrium states, the one-dimensional simple exclusion process is introduced as a paradigmatic nonequilibrium interacting particle system. The stationary measure on the ring is derived and the idea of the hydrodynamic limit is sketched. We then introduce the phenomenological Kardar-Parisi-Zhang (KPZ) equation and explain the associated universality conjecture for surface fluctuations in growth models. This is followed by a detailed exposition of a seminal paper of Johansson that relates the current fluctuations of the totally asymmetric simple exclusion process (TASEP) to the Tracy-Widom distribution of random matrix theory. The implications of this result are discussed within the framework of the KPZ conjecture.Comment: 52 pages, 4 figures; to appear in J. Phys. A: Math. Theo

Monoacylglycerol lipase inhibition-induced changes in plasma corticosterone levels, anxiety and locomotor activity in male CD1 mice

The hypothalamus-pituitary-adrenal-axis is strongly controlled by the endocannabinoid system. The specific impact of enhanced 2-arachidonoylglycerol signaling on corticosterone plasma levels, however, was not investigated so far. Here we studied the effects of the recently developed monoacylglycerol lipase inhibitor JZL184 on basal and stress-induced corticosterone levels in male CD1 mice, and found that this compound dramatically increased basal levels without affecting stress responses. Since acute changes in corticosterone levels can affect behavior, JZL184 was administered concurrently with the corticosterone synthesis inhibitor metyrapone, to investigate whether the previously shown behavioral effects of JZL184 are dependent on corticosterone. We found that in the elevated plus-maze, the effects of JZL184 on "classical" anxiety-related measures were abolished by corticosterone synthesis blockade. By contrast, effects on the "ethological" measures of anxiety (i.e. risk assessment) were not affected by metyrapone. In the open-field, the locomotion-enhancing effects of the compound were not changed either. These findings show that monoacylglycerol lipase inhibition dramatically increases basal levels of corticosterone. This endocrine effect partly affects the anxiolytic, but not the locomotion-enhancing effects of monoacylglycerol lipase blockade

Long-term outcomes five years after selective dorsal rhizotomy

<p>Abstract</p> <p>Background</p> <p>Selective dorsal rhizotomy (SDR) is a well accepted neurosurgical procedure performed for the relief of spasticity interfering with motor function in children with spastic cerebral palsy (CP). The goal is to improve function, but long-term outcome studies are rare. The aims of this study were to evaluate long-term functional outcomes, safety and side effects during five postoperative years in all children with diplegia undergoing SDR combined with physiotherapy.</p> <p>Methods</p> <p>This study group consisted of 35 children, consecutively operated, with spastic diplegia, of which 26 were Gross Motor Function Classification System (GMFCS) levels III–V. Mean age was 4.5 years (range 2.5–6.6). They were all assessed by the same multidisciplinary team at pre- and at 6, 12, 18 months, 3 and 5 years postoperatively. Clinical and demographic data, complications and number of rootlets cut were prospectively registered. Deep tendon reflexes and muscle tone were examined, the latter graded with the modified Ashworth scale. Passive range of motion (PROM) was measured with a goniometer. Motor function was classified according to the GMFCS and measured with the Gross Motor Function Measure (GMFM-88) and derived into GMFM-66. Parent's opinions about the children's performance of skills and activities and the amount of caregiver assistance were measured with Pediatric Evaluation Disability Inventory (PEDI).</p> <p>Results</p> <p>The mean proportion of rootlets cut in S2-L2 was 40%. Muscle tone was immediately reduced in adductors, hamstrings and dorsiflexors (p < 0.001) with no recurrence of spasticity over the 5 years. For GMFCS-subgroups I–II, III and IV–V significant improvements during the five years were seen in PROM for hip abduction, popliteal angle and ankle dorsiflexion (p = 0.001), capacity of gross motor function (GMFM) (p = 0.001), performance of functional skills and independence in self-care and mobility (PEDI) (p = 0.001).</p> <p>Conclusion</p> <p>SDR is a safe and effective method for reducing spasticity permanently without major negative side effects. In combination with physiotherapy, in a group of carefully selected and systematically followed young children with spastic diplegia, it provides lasting functional benefits over a period of at least five years postoperatively.</p

Activity theory, complexity and sports coaching: An epistemology for a discipline

The aim of this article is two-fold. Firstly, it is to advance the case for Activity Theory (AT) as a credible and alternative lens to view and research sports coaching. Secondly, it is to position this assertion within the wider debate about the epistemology of coaching. Following a framing introduction, a more comprehensive review of the development and current conceptualisation of AT is given. Here, AT’s evolution through three distinct phases and related theorists, namely Vygotsky, Leont’ev and Engeström, is initially traced. This gives way to a more detailed explanation of AT’s principal conceptual components, including ‘object’, ‘subject’, ‘tools’ (mediating artefacts), ‘rules’, a ‘community’ and a ‘division of labour’. An example is then presented from empirical work illustrating how AT can be used as a means to research sports coaching. The penultimate section locates such thinking within coaching’s current ‘epistemological debate; arguing that the coaching ‘self’ is not an autonomous individual, but a relative part of social and cultural arrangements. Finally, a conclusion summarises the main points made, particularly in terms in presenting the grounding constructivist epistemology of AT as a potential way forward for sports coaching

PhoP: A Missing Piece in the Intricate Puzzle of Mycobacterium tuberculosis Virulence

Inactivation of the transcriptional regulator PhoP results in Mycobacterium tuberculosis attenuation. Preclinical testing has shown that attenuated M. tuberculosis phoP mutants hold promise as safe and effective live vaccine candidates. We focused this study to decipher the virulence networks regulated by PhoP. A combined transcriptomic and proteomic analysis revealed that PhoP controls a variety of functions including: hypoxia response through DosR crosstalking, respiratory metabolism, secretion of the major T-cell antigen ESAT-6, stress response, synthesis of pathogenic lipids and the M. tuberculosis persistence through transcriptional regulation of the enzyme isocitrate lyase. We also demonstrate that the M. tuberculosis phoP mutant SO2 exhibits an antigenic capacity similar to that of the BCG vaccine. Finally, we provide evidence that the SO2 mutant persists better in mouse organs than BCG. Altogether, these findings indicate that PhoP orchestrates a variety of functions implicated in M. tuberculosis virulence and persistence, making phoP mutants promising vaccine candidates

Reverse Effect of Mammalian Hypocalcemic Cortisol in Fish: Cortisol Stimulates Ca2+ Uptake via Glucocorticoid Receptor-Mediated Vitamin D3 Metabolism

Cortisol was reported to downregulate body-fluid Ca2+ levels in mammals but was proposed to show hypercalcemic effects in teleostean fish. Fish, unlike terrestrial vertebrates, obtain Ca2+ from the environment mainly via the gills and skin rather than by dietary means, and have to regulate the Ca2+ uptake functions to cope with fluctuating Ca2+ levels in aquatic environments. Cortisol was previously found to regulate Ca2+ uptake in fish; however, the molecular mechanism behind this is largely unclear. Zebrafish were used as a model to explore this issue. Acclimation to low-Ca2+ fresh water stimulated Ca2+ influx and expression of epithelial calcium channel (ecac), 11β-hydroxylase and the glucocorticoid receptor (gr). Exogenous cortisol increased Ca2+ influx and the expressions of ecac and hydroxysteroid 11-beta dehydrogenase 2 (hsd11b2), but downregulated 11β-hydroxylase and the gr with no effects on other Ca2+ transporters or the mineralocorticoid receptor (mr). Morpholino knockdown of the GR, but not the MR, was found to impair zebrafish Ca2+ uptake function by inhibiting the ecac expression. To further explore the regulatory mechanism of cortisol in Ca2+ uptake, the involvement of vitamin D3 was analyzed. Cortisol stimulated expressions of vitamin D-25hydroxylase (cyp27a1), cyp27a1 like (cyp27a1l), 1α-OHase (cyp27b1) at 3 dpf through GR, the first time to demonstrate the relationship between cortisol and vitamin D3 in fish. In conclusion, cortisol stimulates ecac expression to enhance Ca2+ uptake functions, and this control pathway is suggested to be mediated by the GR. Lastly, cortisol also could mediate vitamin D3 signaling to stimulate Ca2+ uptake in zebrafish

Change in left ventricular geometry during antihypertensive treatment in children with primary hypertension

The pattern of the left ventricle (LV) has important significance in adults with hypertension. The aim of the present study was to analyze changes and determinants of LV geometry after 1 year of antihypertensive treatment in children with primary hypertension (PH) in relation to metabolic abnormalities and anthropometrical parameters. In 86 children (14.1 ± 2.4 years) with newly diagnosed PH, LV geometry and biochemical parameters before and after 12 months of standard antihypertensive therapy were assessed. At baseline, normal LV geometry (NG) was found in 42 (48.9%), concentric remodeling (CR) in 4 (4.6%), concentric hypertrophy (CH) in 8 (9.3%), and eccentric hypertrophy (EH) in 32 (37.2%) patients. The prevalence of NG in patients with severe hypertension was significantly lower than in patients with ambulatory hypertension. There were no differences in dipping status in relation to LV geometry. Patients with CH and EH were more viscerally obese than patients with NG. Patients with CH had higher diastolic blood pressure in comparison with EH patients (p < 0.05). The main predictor of relative wall thickness (RWT) was the triglycerides to high density lipoprotein cholesterol (TG/HDL) ratio (R2 = 0.319, β = 0.246, p = 0.004). Patients received 12 months of antihypertensive treatment, either lifestyle modification only (n = 37) or lifestyle modification plus antihypertensive medications (n = 49) if severe ambulatory hypertension or target organ damage were present. After 12 months of treatment the prevalence of EH (37.2% vs 18.6%, p = 0.003) decreased but prevalence of CH did not change. Patients in whom RWT decreased also decreased waist circumference and TG/HDL; the main predictor of RWT decrease was a decrease of the TG/HDL ratio (β = 0.496, R2 = 0.329, p = 0.002). In adolescents with PH, LV geometry is related to central obesity and insulin resistance. Decrease of abdominal obesity and insulin resistance are the most important predictors of normalization of LV geometry, however CH has lower potential to normalize LV geometry