A new interpretation of the period-luminosity sequences of long-period variables

Period-luminosity (PL) sequences of long period variables (LPVs) are commonly interpreted as different pulsation modes, but there is disagreement on the modal assignment. Here, we re-examine the observed PL sequences in the Large Magellanic Cloud, including the sequence of long secondary periods (LSPs), and their associated pulsation modes. Firstly, we theoretically model the sequences using linear, radial, non-adiabatic pulsation models and a population synthesis model of the LMC red giants. Then, we use a semi-empirical approach to assign modes to the pulsation sequences by exploiting observed multi-mode pulsators. As a result of the combined approaches, we consistently find that sequences B and C$^{\prime}$ both correspond to first overtone pulsation, although there are some fundamental mode pulsators at low luminosities on both sequences. The masses of these fundamental mode pulsators are larger at a given luminosity than the mass of the first overtone pulsators. These two sequences B and C$^{\prime}$ are separated by a small period interval in which large amplitude pulsation in a long secondary period (sequence D variability) occurs, meaning that the first overtone pulsation is not seen as the primary mode of pulsation. Observationally, this leads to the splitting of the first overtone pulsation sequence into the two observed sequences B and C$^{\prime}$. Our two independent examinations also show that sequences A$^{\prime}$, A and C correspond to third overtone, second overtone and fundamental mode pulsation, respectively.Comment: 10 pages, 7 figures, accepted for publication in Ap

The effects of recent austerity on environmental protection decisions:evidence and perspectives from Scotland

Purpose: The purpose of this paper is to establish the evidence for, the why and how recent austerity policy atmosphere associated with the UK government affected environmental protection decisions within planning in Scotland. Design/methodology/approach: A qualitative analysis based on perspectives gathered via questionnaire survey targeted at stakeholders involved in planning in Scotland was undertaken. The questionnaire responses were analysed thematically, supplemented by using statistical tests of significance and variance to show how responses differed across participants. Findings: The evidence showed that austerity policy atmosphere resulted in a pervasive neoliberal imperative of resuscitating the economy; whilst producing subtle and adverse effects on environmental decisions. This was best understood within a neo-Gramscian perspective of hegemony, borrowed from the field of political economy of states. Research limitations/implications: The gathered views were constrained within unknown biases that the participants may have had; and because the case study approach was not equipped to generalize the results beyond the study, more research testing cause-effect between the austerity and selected environmental parameters is needed, from various contexts. Practical implications: Decision-making frameworks should explicitly acknowledge the unique pressures during austerity periods; and contemplate resilient decision-making frameworks that can withstand the hegemonic tendencies which prioritise economic goals above environmental ones. Originality/value: Whilst the area of austerity’s impacts on the environment remains poorly evidenced, empirically, this seminal paper uses robust analysis to establish how the austerity policy atmosphere affects environmental decisions. This is insight into what may be happening in other similar situations outside Scotland, raising concern as to whether and how we should approach the challenge of hegemonic ideas

ISOKINETIC LEG STRENGTH CHANGES IN YOUNG FEMALE SOUTH AFRICAN RECRUITS FOLLOWING BASIC MILITARY TRAINING

Isokinetic testing was used to assess upper and lower leg isokinetic strength changes in 83 female recruits (age 20.2 ± 1.8 years; body mass 60.2 ± 9.2kg; stature 158.0 ±16.8cm) pre and post 12-weeks of basic military training. The cohort completed 48 periods of physical training incorporating a 10% weekly progression and „Pole PT‟ exercises introduced from the fifth week of basic military training. No statistically significant (

TRICEPS SURAE MUSCULOTENDINOUS STIFFNESS: RELATIVE DIFFERENCES BETWEEN SOCCER AND NON-SOCCER PLAYERS

The purpose of this study was to investigate the muscle-tendon unit stiffness of the ankle between professional soccer players and non-soccer players. Fifteen soccer players and twenty-one non-soccer players participated in this study. The stiffness of the triceps surae muscle-tendon unit was measured in vivo from the damped frequency of oscillation of the shank about the ankle using a free oscillation technique. Using the t-test no significant differences (P > 0.05) were found between the soccer and the control groups for muscle-tendon unit stiffness of the triceps surae. The soccer group showed stiffness values of 22059 (SD 3623) N/m, while the control group showed values of 20427 (SD 4517) N/m. These results suggest that neither the soccer training nor the games itself affected the stiffness of the ankle of the players

Molecular and Cellular Characterization of the TH Pathway in the Sea Urchin Strongylocentrotus purpuratus

Thyroid Hormones (THs) are a class of signaling molecules produced by coupling iodine with tyrosine residues. In vertebrates, extensive data support their important role in a variety of processes such as metabolism, development and metamorphosis. On the other hand, in invertebrates, the synthesis and role of the THs have been, so far, poorly investigated, thus limiting our understanding of the function and evolution of this important animal signaling pathway. In sea urchins, for example, while several studies focused on the availability and function of external sources of iodotyrosines, preliminary evidence suggests that an endogenous TH pathway might be in place. Here, integrating available literature with an in silico analysis, various homologous genes of the vertebrate TH molecular toolkit have been identified in the sea urchin Strongylocentrotus purpuratus. They include genes involved in the synthesis (Sp-Pxdn), metabolism (Sp-Dios), transport (Sp-Ttrl, Sp-Mct7/8/10) and response (Sp-Thr, Sp-Rxr and Sp-Integrin αP) to thyroid hormones. To understand the cell type(s) involved in TH synthesis and/or response, we studied the spatial expression of the TH toolkit during urchin development. Exploiting single-cell transcriptomics data in conjunction with in situ hybridization and immunohistochemistry, we identified cell types that are potentially producing or responding to THs in the sea urchin. Finally, growing sea urchin embryos until the larva stage with and without a source of inorganic iodine, we provided evidence that iodine organification is important for larval skeleton growth

Accretion Disks Around Young Objects. II. Tests of Well-Mixed Models with Ism Dust

We construct detailed vertical structure models of irradiated accretion disks around T Tauri stars with interstellar medium dust uniformly mixed with gas. The dependence of the structure and emission properties on mass accretion rate, viscosity parameter, and disk radius is explored using these models. The theoretical spectral energy distributions (SEDs) and images for all inclinations are compared with observations of the entire population of Classical T Tauri stars (CTTS) and Class I objects in Taurus. In particular, we find that the median near-infrared fluxes can be explained within the errors with the most recent values for the median accretion rates for CTTS. We further show that the majority of the Class I sources in Taurus cannot be Class II sources viewed edge-on because they are too luminous and their colors would be consistent with disks seen only in a narrow range of inclinations. Our models appear to be too geometrically thick at large radii, as suggested by: (a) larger far-infrared disk emission than in the typical SEDs of T Tauri stars; (b) wider dark dust lanes in the model images than in the images of HH30 and HK Tau/c; and (c) larger predicted number of stars extincted by edge-on disks than consistent with current surveys. The large thickness of the model is a consequence of the assumption that dust and gas are well-mixed, suggesting that some degree of dust settling may be required to explain the observations.Comment: 41 pages, 13 figures, accepted in Ap

Smoke and clouds above the Southeast Atlantic: upcoming field campaigns probe absorbing aerosol’s impact on climate

ArticleFrom July through October, smoke from biomass burning fires on the southern African sub-continent are transported westward through the free troposphere over one of the largest stratocumulus cloud decks on our planet. Biomass burning aerosol (smoke) absorbs shortwave radiation efficiently. This fundamental property implicates smoke within myriad small-scale processes with potential large-scale impacts on climate that are not yet well-understood. A coordinated, international team of scientists from the United States, United Kingdom, France, South Africa and Namibia will provide an unprecedented interrogation of this smoke-and-cloud regime from 2016 to 2018, using multiple aircraft and surface-based instrumentation suites to span much of the breadth of the southeast Atlantic

Modelling Long-Period Variables -- II. Fundamental mode pulsation in the nonlinear regime

Long-period variability in luminous red giants has several promising applications, all of which require models able to accurately predict pulsation periods. Linear pulsation models have proven successful in reproducing the observed periods of overtone modes in evolved red giants, but they fail to accurately predict their fundamental mode periods. Here, we use a 1D hydrodynamic code to investigate the long-period variability of M-type asymptotic giant branch stars in the nonlinear regime. We examine the period and stability of low-order radial pulsation modes as a function of mass and radius, and find overtone mode periods in complete agreement with predictions from linear pulsation models. In contrast, nonlinear models predict an earlier onset of dominant fundamental mode pulsation, and shorter periods at large radii. Both features lead to a substantially better agreement with observations, that we verify against OGLE and Gaia data for the Magellanic Clouds. We provide simple analytic relations describing the nonlinear fundamental mode period-mass-radius relation. Differences with respect to linear predictions originate from the readjustment of the envelope structure induced by large-amplitude pulsation. We investigate the impact of turbulent viscosity on linear and nonlinear pulsation, and probe possible effects of varying metallicity and carbon abundance.Comment: 18 pages, 17 figures; accepted for publication in MNRA

Military fitness of young South African adults : does it comply with requirements?

The fitness of today's young people is reported to be at a very low level, and this is disconcerting considering that some are needed as military recruits but will not be accepted if they do not pass the military fitness tests. The aims of this study were to investigate the pass rate of young adults (n=41) in the standard South African National Defence Force (SANDF) fitness test, and to establish whether the pass rate of the male (n=31) and female (n=10) participants differed significantly. A cross-sectional case report design was used as the research method. All participants aged 18.0 to 22.9 years underwent tests for body composition, handgrip strength, vertical jump and multistage shuttle run. After a 48-hour rest period the SANDF tests were carried out. For analysis the descriptive statistics and the non-parametric Mann-Whitney U-Test were used. The p-value was set at 0.05. The following results were obtained: 85.4% of the cohort failed the test, of that 90.6% of the males (m) failed and 60.0% of the females (f) failed. Significant differences (p<0,01) were found between the male and female participants in their height (m=171.9 m; f=164.2 m); weight (m=76.9 kg; f=63.6 kg); percentage body fat (m=19,2%; f=28.0%); explosive power (m= 1254.5 watt; f=947.1 watt); handgrip dynamometer strength (m=99.4 kg; f=67.9 kg); and SANDF passing scores (p≤0.05) (m=2 006; f=2 567). No significant differences were observed on the indirect relative Vo2max reading (m=41.7 ml/kg/min; f=38.2 ml/kg/min); body mass index (m=24.3 kg/m²; f=23.5 kg/m²); and the sit-and-reach test (m=33.6 cm; f=36.5 cm). It was concluded that female participants performed better than their male counterparts but that all the young people tested did not comply with the fitness requirements of the SANDF. As the majority of the cohort complied with the normal limits set for the general fitness tests, it was concluded that the level of fitness needed to pass the SANDF fitness test was higher than the level of fitness prescribed for the general population.http://www.ajol.info/journal_index.php?jid=153&ab=ajpher

OKUSNA REAKCIJA ŠARANA CYPRINUS CARPIO NA PROMJENJIVE KONCENTRACIJE DVIJU STIMULATIVNIH AMINOKISELINA

Common carp possesses a highly evolved gustatory system that is stimulated by a narrow range of free amino acids including L-cysteine and L-proline. A synergetic effect on the gustatory response of a combination of these two substances has not previously been demonstrated. In this study, groups of common carp were randomly presented with different concentrations of L-cysteine (0-0.1 M) and L-proline (0-0.05 M) in agar pellets in one minute trials. First retention duration, total retention duration during each trial and the number of ingestions (pellet acceptances) were recorded for each of a total of 690 trials. Palatability, pellet consumption rate and average pellet acceptances were calculated for each pellet type. It was shown that L-cysteine was more highly stimulatory than L-proline but no synergism between the two regarding the gustatory response was observed. The results are relevant for the formulation of aquafeeds and angling baits for carp.Šaran ima visoko razvijeni okusni sustav kojeg stimulira uski raspon slobodnih aminokiselina uključujući L-cistein i L-prolin. Sinergijski učinak kombinacije ovih dviju tvari na okusnu reakciju nije ranije dokazivan. U ovoj studiji različite koncentracije L-cisteina (0-0,1 M) i L-prolina (0-0,05 M) nasumce su davane testnim skupinama šarana u peletama agara tijekom jednominutnih pokusa. Trajanje prvog zadržavanja i ukupno trajanje zadržavanja tijekom svakog pokusa te broj gutanja (uzimanja) pelete zabilježeni su za svaki od ukupno 690 testova. Za svaki tip pelete izračunata je okusna reakcija, broj konzumacija i prosječno prihvaćanje od strane šarana. Pokazalo se da L-cistein znatno više stimulira konzumaciju od L-prolina te između njih nije uočen sinergizam. Rezultati su važni za pripremanje riblje hrane i ribičkih mamaca za šarane