Probing and raising lithium problems with hadronic gamma rays and cosmic-ray nucleosynthesis

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Demand management for home energy networks using cost-optimal appliance scheduling

This paper uses problem decomposition to show that optimal dynamic home energy prices can be used to reduce the cost of supplying energy, while at the same time reducing the cost of energy for the home users. The paper makes no specific recommendations on the nature of energy pricing, but shows that energy prices can normally be found that not only result in optimal energy consumption schedules for the energy provider's problem and are economically viable for the energy provider, but also reduce total users energy costs. Following this, the paper presents a heuristic real-time algorithm for demand management using home appliance scheduling. The presented algorithm ensures users' privacy by requiring users to only communicate their aggregate energy consumption schedules to the energy provider at each iteration of the algorithm. The performance of the algorithm is evaluated using a comprehensive probabilistic user demand model which is based on real user data from energy provider E.ON. The simulation results show potential reduction of up to 17% of the mean peak-to-average power estimate, reducing the user daily energy cost for up to 14%

Understanding the diffuse gamma ray emission of the milky way - from supernova remnants to dark matter

Diffuse gamma ray emission from the Galactic center at 2-3 GeV, as well as the 12 TeV gamma ray excess in the Galactic disk, remain open for debate and represent the missing puzzles in the complete picture of the high-energy Milky Way sky. Our papers emphasize the importance of understanding all of the populations that contribute to the diffuse gamma background in order to discriminate between the astrophysical sources such as supernova remnants and pulsars, and something that is expected to be seen in gamma rays and is much more exotic - dark matter. We analyze two separate data sets that have been measured in different energy ranges from the ?Fermi-LAT? and ?Milagro? telescopes, using these as a powerful tool to limit and test our analytical source population models. We model supernova remnants and pulsars, estimating the number of still undetected ones that contribute to the diffuse background, trying to explain both the Galactic center and the 12 TeV excess. Furthermore, we aim to predict the number of soon to be detected sources with new telescopes, such as the ?HAWC?

Multiscale modeling of twitch contractions in cardiac trabeculae

© 2021 Mijailovich et al. Understanding the dynamics of a cardiac muscle twitch contraction is complex because it requires a detailed understanding of the kinetic processes of the Ca2+ transient, thin-filament activation, and the myosin-actin cross-bridge chemomechanical cycle. Each of these steps has been well defined individually, but understanding how all three of the processes operate in combination is a far more complex problem. Computational modeling has the potential to provide detailed insight into each of these processes, how the dynamics of each process affect the complexity of contractile behavior, and how perturbations such as mutations in sarcomere proteins affect the complex interactions of all of these processes. The mechanisms involved in relaxation of tension during a cardiac twitch have been particularly difficult to discern due to nonhomogeneous sarcomere lengthening during relaxation. Here we use the multiscale MUSICO platform to model rat trabecular twitches. Validation of computational models is dependent on being able to simulate different experimental datasets, but there has been a paucity of data that can provide all of the required parameters in a single experiment, such as simultaneous measurements of force, intracellular Ca2+ transients, and sarcomere length dynamics. In this study, we used data from different studies collected under similar experimental conditions to provide information for all the required parameters. Our simulations established that twitches either in an isometric sarcomere or in fixed-length, multiple-sarcomere trabeculae replicate the experimental observations if models incorporate a length-tension relationship for the nonlinear series elasticity of muscle preparations and a scheme for thick-filament regulation. The thick-filament regulation assumes an off state in which myosin heads are parked onto the thick-filament backbone and are unable to interact with actin, a state analogous to the super-relaxed state. Including these two mechanisms provided simulations that accurately predict twitch contractions over a range of different conditions

Smart-ening up the hijab: the materiality of contemporary British Muslim veiling in the physical and the digital

The contemporary Muslim hijab (veil) in Britain takes its form through myriad material expressions including individual style shaped around current fashion trends. Yet its religio-cultural history and connections with activist youth identity politics makes it a contentious object that provokes much debate and interpretation. This essay concentrates on the hijab's materiality and affect: specifically it explores how the material handling of a piece of cloth or scarf, how its feel and its texture, allows Muslim women to create a Muslim identity through embodiment based on their feelings, desires and subjectivity. The essay explores the manipulation of the cloth, its folding and draping, and how this transforms a wearer’s identity into a Muslim ‘look’ for a Muslim ‘self’. The discussion unravels the ways in which the crafting of the hijab exposes a wearer’s skill and dexterity to create different affects; it also considers technological innovation and tech-inspired design change as factors that create new opportunities for Muslim women to subvert stereotypes and fashion systems though ‘smart' hijab wearing

UTICAJ ĐUBRENJA AZOTOM I PODSEJAVANJA NA PRINOS I KVALITET TRAVNJAKA CYNOSURETUM CRISTATI U PLANINSKOM PODRUČJU SRBIJE

The trial was carried out during two years (2003 and 2004) on Cynosuretum cristati-type meadow in the hillymountainous region of Serbia (altitude 1158 m). The investigation included five nitrogen fertilizer rates (0, 40, 80, 120 and 160 kg ha-1 yr-1) and undersowing with red clover and birdsfoot trefoil. Increase in nitrogen fertilization level resulted in corresponding increases in the quantity and quality of grass, while legumes and other herbages decreased. Maximum two-year average dry matter yield of 4.44 t ha-1 was achieved with the highest N rate (160 kg ha-1). The increase was 2.03 t ha-1 or 85.0% compared with the control. Increased N rates increasing the contents of protein, ash, fat, Cu, Co, and NO3, and reduced the contents of cellulose, K, P, Ca, Mg, S, Zn, and B. Dry matter yield in the undersowing treatment was low, only slightly over that of the control in both study years. Furthermore, undersowing failed to affect the chemical and mineral composition of dry matter.Istraživanje je obavljeno na travnjaku tipa Cynosuretum cristati u planinskom području Srbije, na nadmorskoj visini oko 1158 m, tokom dve godine (2002 - 2003. g.). U istraživanju je proučavan uticaj azotnog đubriva i podsejavanja sa crvenom detelinom i žutim zvezdanom na prinos suve materije (SM) u sledećim varijantama đubriva (0, 40, 80, 120 i 160 kg/ha). Sa povećanjem količine azotnog đubriva povećao se udeo i kvalitet trava a udeo leptirnjača i bioljaka iz ostalih familija se smanjivao. Maksimalan dvogodišnji prosečan prinos SM je iznosio 4.44 t ha-1 a postignut je sa najvećom količinom azotnog đubriva (160 kg ha-1). Povećanje je iznosilo 2.03 t ha-1 ili 85.0% u odnosu na kontrolu. Sa povećanjem količine primenjenog azotnog đubriva povećavao se sadržaj proteina, pepela, masti Cu, Co i NO3, a smanjivala količina celuloze, K, P, Ca, Mg, S, Zn i B. Prinos SM sa primenom podsejavanja je bio nizak, nešto viši u odnosu na kontrolu u obe godine istraživanja. Primena podsejavanja nije imala uticaja na promenu hemijskog i mineralnog sastava u SM prinosa

Nucleosynthesis Constraints on a Massive Gravitino in Neutralino Dark Matter Scenarios

The decays of massive gravitinos into neutralino dark matter particles and Standard Model secondaries during or after Big-Bang nucleosynthesis (BBN) may alter the primordial light-element abundances. We present here details of a new suite of codes for evaluating such effects, including a new treatment based on PYTHIA of the evolution of showers induced by hadronic decays of massive, unstable particles such as a gravitino. We also develop an analytical treatment of non-thermal hadron propagation in the early universe, and use this to derive analytical estimates for light-element production and in turn on decaying particle lifetimes and abundances. We then consider specifically the case of an unstable massive gravitino within the constrained minimal supersymmetric extension of the Standard Model (CMSSM). We present upper limits on its possible primordial abundance before decay for different possible gravitino masses, with CMSSM parameters along strips where the lightest neutralino provides all the astrophysical cold dark matter density. We do not find any CMSSM solution to the cosmological Li7 problem for small m_{3/2}. Discounting this, for m_{1/2} ~ 500 GeV and tan beta = 10 the other light-element abundances impose an upper limit m_{3/2} n_{3/2}/n_\gamma < 3 \times 10^{-12} GeV to < 2 \times 10^{-13} GeV for m_{3/2} = 250 GeV to 1 TeV, which is similar in both the coannihilation and focus-point strips and somewhat weaker for tan beta = 50, particularly for larger m_{1/2}. The constraints also weaken in general for larger m_{3/2}, and for m_{3/2} > 3 TeV we find a narrow range of m_{3/2} n_{3/2}/n_\gamma, at values which increase with m_{3/2}, where the Li7 abundance is marginally compatible with the other light-element abundances.Comment: 74 pages, 40 Figure

Barium effect on germination, plant growth, and antioxidant enzymes in Cucumis sativus L. plants

Barium (Ba) is a nonessential element that can cause several deleterious effects in most organisms. Elevated Ba concentrations can be toxic for plants and may affect growth and disturbances in homeostasis. This study aimed to evaluate the Ba stress, the plant-tolerance limits, and the detoxification strategy adopted by Cucumis sativus L. The effect of Ba on seed's germination and vegetative development of this species was evaluated. For germination test, different Ba concentrations were used (0, 200, 500, 1,000, and 2,000 μM). Results showed that germination was stimulated with 500 and 2,000 µM of Ba. The toxicity effect on plant development was studied by treating the plants with increasing doses of Ba (100, 200, 300, and 500 μM) during 45 days. Shoot and root dry biomass production decreased significantly with elevated Ba concentrations, although water content enhanced in the roots. The concentration of Ba, 500 µM, induced high Ba accumulation in shoots and roots (9 times higher than in the control plants). Moreover, results showed that catalase, guaiacol peroxidase, and ascorbate peroxidase activities were stimulated in the different tissues of cucumber plants which highlight the occurring of an oxidative damage through Ba treatments and the involvement of the plant enzymatic antioxidant defense system

A Bitter Pill: The Primordial Lithium Problem Worsens

The lithium problem arises from the significant discrepancy between the primordial 7Li abundance as predicted by BBN theory and the WMAP baryon density, and the pre-Galactic lithium abundance inferred from observations of metal-poor (Population II) stars. This problem has loomed for the past decade, with a persistent discrepancy of a factor of 2--3 in 7Li/H. Recent developments have sharpened all aspects of the Li problem. Namely: (1) BBN theory predictions have sharpened due to new nuclear data, particularly the uncertainty on 3He(alpha,gamma)7Be, has reduced to 7.4%, and with a central value shift of ~ +0.04 keV barn. (2) The WMAP 5-year data now yields a cosmic baryon density with an uncertainty reduced to 2.7%. (3) Observations of metal-poor stars have tested for systematic effects, and have reaped new lithium isotopic data. With these, we now find that the BBN+WMAP predicts 7Li/H = (5.24+0.71-0.67) 10^{-10}. The Li problem remains and indeed is exacerbated; the discrepancy is now a factor 2.4--4.3 or 4.2sigma (from globular cluster stars) to 5.3sigma (from halo field stars). Possible resolutions to the lithium problem are briefly reviewed, and key nuclear, particle, and astronomical measurements highlighted.Comment: 21 pages, 4 figures. Comments welcom