129,543 research outputs found
Lepton Flavour Violating Decays in the Littlest Higgs Model with T-Parity
We present the results of an extensive analysis of lepton flavour violating
decays in the Littlest Higgs model with T-parity (LHT). As lepton flavour
violation is highly suppressed in the Standard Model by small neutrino masses,
the LHT effects turn out to be naturally huge and could be seen in the near
future experiments.Comment: 3 pages, 1 table. Proceedings of the talk presented at the EPS
Conference on High Energy Physics 2007, Mancheste
Distribution of Return Intervals of Extreme Events
The distribution of return intervals of extreme events is studied in time
series characterized by finite-term correlations with non-exponential decay.
Precisely, it has been analyzed the statistics of the return intervals of
extreme values of the resistance fluctuations displayed by resistors with
granular structure in nonequilibrium stationary states. The resistance
fluctuations are calculated by Monte Carlo simulations using a resistor network
approach. It has been found that for highly disordered networks, when the
auto-correlation function displays a non-exponential and non-power-law decay,
the distribution of return intervals of the extreme values is a stretched
exponential, with exponent independent of the threshold.Comment: 10 pages, 6 figures, Next-SigmaPhi Int. Conference, News Expectations
and Trends in Statistical Physics, 13-18 August 2005, Kolymbari - Crete
(Greece
Wrapped forages for horses
Wrapped forages, in the form of silage and haylage, have become more common in horse diets during recent years. Silage and haylage is commonly produced in big bales. However, for use in stables with few animals, these bales often contain too much forage to be consumed before onset of aerobic deterioration. Smaller bales are therefore of interest, but knowledge of the chemical composition (including vitamin content), fermentation pattern and changes in those variables during storage of small bales is limited, and was therefore investigated. Small bale forage contained higher pH, higher ethanol and lower lactic acid content, compared to general levels in chopped silo silage, but low levels of ammonia-N and butyric acid. There were no general effects of dry matter or extent of fermentation on α-tocopherol and β-carotene contents in the preserved forages, but linear positive correlations between the vitamins and lactic acid existed. In general, long-term storage (14 months) of small bales influenced fermentation variables, yeasts and pH, but silage was affected by storage to a larger extent than haylage. Although changes occurred during storage, values in two month old bales correlated well with values obtained after 14 months. The influence of forage conservation methods on horse preference was also investigated. Hay, haylage and silage were produced from the same grass crops and the forages were offered simultaneously to horses. Silage was the first chosen forage, had the highest rate of consumption and the longest eating time, while hay had the lowest consumption rate and the shortest eating time. Haylage was intermediate between hay and silage in both eating time and rate of consumption. The influence of forage conservation methods on equine hindgut fermentation was studied using fistulated horses. Hay, haylage and silage were produced from the same grass crop and fed in a changeover study. Horses were sampled after being fed the forage for 21 days, and a kinetic study of colon fermentation was performed in each period. Forage conservation method had no effect on microbial or chemical composition in the right ventral colon or faeces on Day 21. All forages showed similar fermentation kinetics in the right ventral colon before (0h) and at 2, 4, 8 and 12 h after feeding
Bioplastics made from upcycled food waste. Prospects for their use in the field of design
In recent years, the negative effects on the environment of the intensive use of synthetic, oil-derived plastics to make products, even those with a limited required duration, have given renewed impetus to the search for biodegradable and/or compostable materials obtained from renewable sources, particularly biopolymers derived from vegetable, animal or microbial matter that could prove a valid alternative in a number of applications: not only in the packaging industry, but also for making objects with a longer required duration. Indeed, as well as offering the possibility of being used as they are, immediately after having undergone traditional-type mechanical processing, it is also possible to mix, supplement and modify them both on a macro- and nanometric scale, allowing us to significantly increase their properties and performance and adapt them to a wide variety of needs.
However, the real challenge is to create new materials from food waste and not from specially grown crops, whose production has, in any case, an environmental cost. This allows us to reduce the waste produced when processing foods, which is usually a practical problem and involves a considerable investment in economic terms. It also helps us address one of the worst problems of our time: that of the waste that sees a third of the food produced worldwide lost along the various steps of the food production chain.
There is an enormous variety of vegetable, animal and microbial waste that can be used to create biopolymers: from the orange peels left over from fruit juice production to the grapes used to produce wine; from chocolate production waste to egg shells and prawns. We can extract the starches, cellulose, pectin, chitin, lactic acid, collagen, blood proteins and gelatin that form the basis of bioplastics from these materials, either extracting them directly or using mechanical or chemical processes. These are true ‘treasure troves’ of substances that can become useful materials thanks to processes of varying complexity.
In recent years, the testing of substances made from food waste has increased significantly; the sheer abundance of raw materials that can be used to make them has encouraged institutional research, as well as an approach to project development that has been widely embraced by many young designers who craft these materials. Nevertheless, there is still no systematic record of the results achieved. This has slowed down their adoption, which in contrast offers enormous potential that is still almost entirely unexplored.
This paper considers all aspects of these materials, starting with the most interesting experiments underway, and envisages possible future scenarios
On the rank of the fibers of elliptic K3 surfaces
Let be an elliptic K3 surface endowed with two distinct Jacobian elliptic
fibrations , , defined over a number field . We prove that
there is an elliptic curve such that the generic rank over of
after a base extension by is strictly larger than the generic rank of
. Moreover, if the generic rank of is positive then there are
infinitely many fibers of () with rank at least the generic
rank of plus one.Comment: 9 page
Relationships between depression, anxiety, and residual problems following recovery from Guillain-Barré Syndrome : a New Zealand survey : a thesis presented in partial fulfilment of the requirements for the degree of Master of Arts in Psychology at Massey University
The present study retrospectively examined the relationships between mental status and residual problems following recovery from Guillain-Barré Syndrome (GBS), and investigated whether depression and anxiety were common post GBS sequelae. Participants were drawn from past and present GBS patients who read about the postal survey in the newsletter of the New Zealand GBS Support Group. Of the 49 adults who responded, 44 individuals completed and returned the questionnaires sent to them via the Support Group Co-ordinator. The set of 4 questionnaires comprised (a) a brief questionnaire about GBS, (b) the McMaster Health Index Questionnaire (MHIQ), a generic quality of life instrument that measures physical, social, and emotional functioning, (c) the Beck Depression Inventory-II (BDI-II), and (d) the 6-Item Short Form of the State Scale of the State-Trait Anxiety Inventory (STAI-6). The MHIQ was completed twice, retrospectively from the point in time when GBS was most severe, and from the present point in time The results showed that half the sample were acutely ill over 6 years ago, yet the majority of the sample reported a number of residual problems with varying levels of severity. Time since diagnosis did not appear to moderate the number or severity of residuals Fatigue was the most common residual (93.2%), but pain and motor-related problems were also common. The majority of participants scored within the minimal depression and anxiety ranges on the BDI-II and the STAI-6, suggesting that depression and anxiety were not common long-lasting sequelae to GBS in this sample. Future research using a prospective design could focus on the incidence of depression and anxiety during the actual recovery phase A study that focussed on the perspectives of caregivers and families would also add important information to the small body of literature regarding the psychosocial aspects of GBS
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