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Web navigation for individuals with dyslexia: An exploratory study
In this paper, we present an exploratory study of the web navigation experiences of dyslexic users. Findings indicate that dyslexics exhibit distinctive web navigation behaviour and preferences. We believe that the outcomes of this study add to our understanding of the particular needs of this web user population and have implications for the design of effective navigation structures
Terpenes and Carbohydrate Source Influence Rumen Fermentation, Digestibility, Intake, and Preference in Sheep
We hypothesized that toxins and nutrients in foods interact to influence foraging behavior by herbivores. Based on this hypothesis we predicted that 1) terpenes in big sagebrush (Artemisia tridentata) influence intake and preference in sheep for diets varying in sources of nonstructural (barley grain) and structural (sugar beet pulp) carbohydrates, and 2) these effects are due to the differential effects of terpenes on fermentation products and apparent digestibility of each class of carbohydrates. Lambs were fed 2 isoenergetic and isonitrogenous diets with varying proportions of the same ingredients (beet pulp- and barley grain-based diet) or offered a choice between the 2 diets; all feeds were fed without and with terpenes, in consecutive periods. We also compared intake and preference of the beet pulp- and barley-based diets before and after the lambs ate a meal of sagebrush. Finally, we assessed the effect of terpenes on ruminal variables and in vivo digestibility. Lambs ate less when fed beet pulp or when they were offered a choice of diets with terpenes (P \u3c 0.001), and intake of the beet pulp-based diet was the most affected (P \u3c 0.05). Lambs preferred the beet pulp- to the grain-based diet with terpenes, but their preference reversed when terpenes were removed from the diets (P \u3c 0.05). When lambs were offered both diets, intake and preference did not differ (P \u3e 0.20) before eating sagebrush, but they preferred the beet pulp-based diet after eating sagebrush (P \u3c 0.05). Intake of sagebrush did not differ among groups consuming the test diets (P = 0.21). Addition of terpenes to both diets increased the digestibility of DM, NDF, and ADF and decreased concentrations of total VFA and acetate (P \u3c 0.05). Terpenes also depressed butyrate concentration in the barley-based diet (P \u3c 0.05). Propionate concentrations were not affected by terpenes in either feed (P = 0.63). In summary, the predominant type of feed ingredient (beet pulp, grain) ingested with terpenes influenced fermentation products, intake, and preference in lambs. The source of energy from supplements, or other plants in the diet, is likely to influence intake and preference for sagebrush in sheep foraging on rangelands. Moreover, ingesting terpenes from sagebrush may also influence intake and preference for other plant species or supplements
Integrating Plant Secondary Metabolites and Foraging Behavior to Enhance Animal Health in Ruminant Production Systems
Legumes and forbs contain bioactives or plant secondary compounds (PSC) with potential to enhance animal health through their antibiotic, antioxidant and immunomodulatory properties that are evident even at small dietary concentrations. In turn, ruminants can regulate their ingestion of PSC through behavioral mechanisms that allow for the efficient achievement of homeostasis. High concentrations of PSC lead to food avoidance, whereas lower content of PSC in the diet achieved through regulatory mechanisms of ingestion could promote medicinal and/or prophylactic effects in the animal and concomitant health benefits to milk and meat products. Under this context, we discuss the restructuring of rangelands and pasturelands through the strategic distribution of legume- and forb-rich patches in monotonous landscapes dominated by grasses, thus re-establishing their functionality. Such strategies can synergistically complement and provide new dimensions (prophylactic-medicinal, product quality) to the forage resources already available to livestock
Mussel watch program for microplastics in the Mediterranean sea: Identification of biomarkers of exposure using Mytilus galloprovincialis
Microplastics (MPs) are ubiquitous pollutants that have also been detected in the aquatic ecosystems at high concentrations. The use of shellfish as bioindicators is widespread for assessing and monitoring the environmental quality in both freshwater and marine environments. On this path, biomarkers represent an effective tool in monitoring programs. This minireview would broaden the existing knowledge on biomarkers of MPs in the Mediterranean mussel Mytilus galloprovincialis. This species was selected as it is widely distributed across the Mediterranean Sea and used as a bioindicator to monitor the presence of MPs in the marine environment. The literature search returned only 11 studies, mainly related to oxidative stress biomarkers. Although certain biomarkers were explored to estimate the effects of MPs on M. galloprovincialis, a battery of standardized and validated biomarkers as well as the inclusion of new ones are needed in future studies to obtain more comparable and robust findings across the Mediterranean Sea
Ecotoxicity of basil (Ocimum Basilicum) extract in aquaculture feeds: Is it really eco-safe for the aquatic environment?
Plant extract and essential oils are gaining application in aquaculture, but data about their environmental impact are limited and their potential effects on aquatic organisms are largely unknown. For this study, ecotoxicity tests were performed under standardized conditions on fish feed supplemented with 3 % w/w of a basil supercritical extract (F1-BEO; substance A), F1-BEO extract (substance B), and fish feed without F1-BEO extract (substance C) on three model species of different trophic levels (bacteria, primary producer, primary consumer) considered representative for freshwater (Aliivibrio fischeri, Raphidocelis subcapitata, Daphnia magna) and marine (A. fischeri, Phaeodactylum tricornutum, Paracentrotus lividus) ecosystems. Ecotoxicological response was largely comparable within the same trophic level (whichever the ecosystem). EC50 was not calculable in the concentration range here tested (3.9–500 mg/L) for freshwater and marine microalgae, suggesting that none of the substances were toxic for primary producers. Reduction of A. fischeri bioluminescence at the tested concentration (0.5–10 mg/L) was observed only for substance A (EC50 9.53 mg/L and 9 mg/L for freshwater and marine ecosystems, respectively). Notably, in P. lividus embryotoxicity was higher for substances A (EC50 1.80 mg/L) and C (EC50 4.6 mg/L) than for substance B (EC50 7.10 mg/L), suggesting a toxic effect due to feed dissolution. In contrast, substance B was more toxic (EC50 0.34 mg/L) in D. magna than substances A (EC50 3.98 mg/L) and C (EC50 5.50 mg/L). Based on the Globally Harmonized System of Classification and Labelling of Chemicals, all substances were categorized Acute 2, except for substance A which was categorized Acute 1 for D. magna. Overall, the substances were found to be potentially toxic for an aquatic ecosystem, especially for primary consumer. Further study of plant extract and essential oils is needed to better understand their effects and fate on the aquatic environment
Increasing the Neutralino Relic Abundance with Slepton Coannihilations: Consequences for Indirect Dark Matter Detection
We point out that if the lightest supersymmetric particle (LSP) is a
Higgsino- or Wino-like neutralino, the net effect of coannihilations with
sleptons is to increase the relic abundance, rather than producing the usual
suppression, which takes place if the LSP is Bino-like. The reason for the
enhancement lies in the effective thermally averaged cross section at
freeze-out: sleptons annihilate (and co-annihilate) less efficiently than the
neutralino(s)-chargino system, therefore slepton coannihilations effectively
act as parasite degrees of freedom at freeze-out. Henceforth, the thermal relic
abundance of LSP's corresponds to the cold Dark Matter abundance for smaller
values of the LSP mass, and larger values of the neutralino pair annihilation
cross section. In turn, at a given thermal neutralino relic abundance, this
implies larger indirect detection rates, as a result of an increase in the
fluxes of antimatter, gamma rays and neutrinos from the Sun orginating from
neutralino pair annihilations.Comment: 16 pages, 6 figures, references added, typos corrected, matches with
the published versio
Low energy antideuterons: shedding light on dark matter
Low energy antideuterons suffer a very low secondary and tertiary
astrophysical background, while they can be abundantly synthesized in dark
matter pair annihilations, therefore providing a privileged indirect dark
matter detection technique. The recent publication of the first upper limit on
the low energy antideuteron flux by the BESS collaboration, a new evaluation of
the standard astrophysical background, and remarkable progresses in the
development of a dedicated experiment, GAPS, motivate a new and accurate
analysis of the antideuteron flux expected in particle dark matter models. To
this extent, we consider here supersymmetric, universal extra-dimensions (UED)
Kaluza-Klein and warped extra-dimensional dark matter models, and assess both
the prospects for antideuteron detection as well as the various related sources
of uncertainties. The GAPS experiment, even in a preliminary balloon-borne
setup, will explore many supersymmetric configurations, and, eventually, in its
final space-borne configuration, will be sensitive to primary antideuterons
over the whole cosmologically allowed UED parameter space, providing a search
technique which is highly complementary with other direct and indirect dark
matter detection experiments.Comment: 26 pages, 7 figures; version to appear in JCA
Shower development of particles with momenta from 15 GeV to 150 GeV in the CALICE scintillator-tungsten hadronic calorimeter
We present a study of showers initiated by electrons, pions, kaons, and
protons with momenta from 15 GeV to 150 GeV in the highly granular CALICE
scintillator-tungsten analogue hadronic calorimeter. The data were recorded at
the CERN Super Proton Synchrotron in 2011. The analysis includes measurements
of the calorimeter response to each particle type as well as measurements of
the energy resolution and studies of the longitudinal and radial shower
development for selected particles. The results are compared to Geant4
simulations (version 9.6.p02). In the study of the energy resolution we include
previously published data with beam momenta from 1 GeV to 10 GeV recorded at
the CERN Proton Synchrotron in 2010.Comment: 35 pages, 21 figures, 8 table
Hadron shower decomposition in the highly granular CALICE analogue hadron calorimeter
The spatial development of hadronic showers in the CALICE scintillator-steel
analogue hadron calorimeter is studied using test beam data collected at CERN
and FNAL for single positive pions and protons with initial momenta in the
range from 10 to 80 GeV/c. Both longitudinal and radial development of hadron
showers are parametrised with two-component functions. The parametrisation is
fit to test beam data and simulations using the QGSP_BERT and FTFP_BERT physics
lists from Geant4 version 9.6. The parameters extracted from data and simulated
samples are compared for the two types of hadrons. The response to pions and
the ratio of the non-electromagnetic to the electromagnetic calorimeter
response, h/e, are estimated using the extrapolation and decomposition of the
longitudinal profiles.Comment: 38 pages, 19 figures, 5 tables; author list changed; submitted to
JINS
Electroweak Baryogenesis and Dark Matter with an approximate R-symmetry
It is well known that R-symmetric models dramatically alleviate the SUSY
flavor and CP problems. We study particular modifications of existing
R-symmetric models which share the solution to the above problems, and have
interesting consequences for electroweak baryogenesis and the Dark Matter (DM)
content of the universe. In particular, we find that it is naturally possible
to have a strongly first-order electroweak phase transition while
simultaneously relaxing the tension with EDM experiments. The R-symmetry (and
its small breaking) implies that the gauginos (and the neutralino LSP) are
pseudo-Dirac fermions, which is relevant for both baryogenesis and DM. The
singlet superpartner of the U(1)_Y pseudo-Dirac gaugino plays a prominent role
in making the electroweak phase transition strongly first-order. The
pseudo-Dirac nature of the LSP allows it to behave similarly to a Dirac
particle during freeze-out, but like a Majorana particle for annihilation today
and in scattering against nuclei, thus being consistent with current
constraints. Assuming a standard cosmology, it is possible to simultaneously
have a strongly first-order phase transition conducive to baryogenesis and have
the LSP provide the full DM relic abundance, in part of the allowed parameter
space. However, other possibilities for DM also exist, which are discussed. It
is expected that upcoming direct DM searches as well as neutrino signals from
DM annihilation in the Sun will be sensitive to this class of models.
Interesting collider and Gravity-wave signals are also briefly discussed.Comment: 50 pages, 10 figure
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