2,362 research outputs found
Atomic data from the Iron Project.XLIII. Transition probabilities for Fe V
An extensive set of dipole-allowed, intercombination, and forbidden
transition probabilities for Fe V is presented. The Breit-Pauli R-matrix (BPRM)
method is used to calculate 1.46 x 10^6 oscillator strengths for the allowed
and intercombination E1 transitions among 3,865 fine-structure levels dominated
by configuration complexes with n <= 10 and l <= 9. These data are complemented
by an atomic structure configuration interaction (CI) calculation using the
SUPERSTRUCTURE program for 362 relativistic quadrupole (E2) and magnetic dipole
(M1) transitions among 65 low-lying levels dominated by the 3d^4 and 3d^ 4s
configurations. Procedures have been developed for the identification of the
large number of fine-structure levels and transitions obtained through the BPRM
calculations. The target ion Fe VI is represented by an eigenfunction expansion
of 19 fine-structure levels of 3d^3 and a set of correlation configurations. Fe
V bound levels are obtained with angular and spin symmetries SL\pi and J\pi of
the (e + Fe VI) system such that 2S+1 = 5,3,1, L <= 10, J <= 8 of even and odd
parities. The completeness of the calculated dataset is verified in terms of
all possible bound levels belonging to relevant LS terms and transitions in
correspondence with the LS terms. The fine-structure averaged relativistic
values are compared with previous Opacity Project LS coupling data and other
works. The 362 forbidden transition probabilities considerably extend the
available data for the E2 and M1 transtions, and are in good agreement with
those computed by Garstang for the 3d^4 transitions.Comment: 19 pages, 1 figure. This paper marks the beginning of a large-scale
effort of ab initio atomic calculations that should eventually lead to
re-calculation of accurate iron opacities. Astron. Astrophys. Suppl. Ser. (in
press
The spherical symmetry Black hole collapse in expanding universe
The spherical symmetry Black holes are considered in expanding background.
The singularity line and the marginally trapped tube surface behavior are
discussed. In particular, we address the conditions whether dynamical horizon
forms for these cosmological black holes. We also discuss about the
cosmological constant effect on these black hole and the redshift of the light
which comes from the marginally trapped tube surface.Comment: 7 pages, 3 figures. Accepted for publication in International Journal
of Modern Physics D (IJMPD). arXiv admin note: text overlap with
arXiv:gr-qc/0308033 and arXiv:gr-qc/030611
Perceptions of Gozitan people about Marine Protected Areas - a quantitative study
Marine Protected Areas (MPAs) serve to protect marine and coastal ecosystems and processes. An effective management plan is crucial for these objectives to be reached and various principles and methods are necessary including education, outreach and awareness building. Due to the limited scope of research on MPAs in Gozo, this study was constructed in order to shed light on the knowledge and values Gozitan people have on MPAs and how education can enact change that leads towards increased social responsibility. Two Gozitan areas with a MPA in their locality (Xagħra and San Lawrenz) and a locality without a MPA (Victoria) were identified as being ideal for this study. A mixed method approach was adopted for this study and entailed the collection of data from qualitative and quantitative aspects. This paper will focus on the quantitative part of the research that consisted of extended questionnaires distributed in the three localities. The analysis of the quantitative data was carried out through SPSS and included descriptive analysis for each question followed by inferential statistics. The study shows that there is lack of knowledge with regards to MPAs and that the value associated with them is mainly ecological. Moreover, results show that there is a general demand for more education and awareness on MPAs. In response to these findings, a model is presented that visually illustrates the links discovered through this research. A number of possible activities involving different stakeholders who could contribute towards incorporating ESD principles in marine education and in fostering social responsibility are presented through a list of recommendations.peer-reviewe
Water management and livelihood choices in southwestern Bangladesh
Coastal Bangladesh faces an increasing number of challenges including cyclones, tidal surges, floods, drought, saline water intrusion, waterlogging and land subsidence, which pose substantial threats to the livelihoods of the coastal inhabitants. In addition to these threats, profound social and land-use changes are complicating the livelihoods of resource users in the region, including the introduction of aquaculture and increasing competition for ground and surface water sources. The government of Bangladesh has targeted this region for investment with irrigation expansion. This paper uses a sustainable livelihood lens to understand the role of investments in water management and irrigation in driving and shaping livelihood changes and transitions over the past ten years and offers recommendations for investments. We find that while water infrastructure development has greatly enhanced the role of agriculture in coastal livelihoods over the last 10 years, further development of irrigation infrastructure should only be prioritized after issues of water governance and inequity across agricultural and aquacultural livelihoods are addressed
Generic Approaches for Node Co operation in Ad hoc Networks
In this paper, we review the approaches that uses the Generic methods to enforce cooperation in ad hoc routing. A very common assumption in the analysis and development of networking algorithms is the full co-operation of the participating nodes. However, the reality may differ considerably. The existence of multiple domains belonging to different authorities or even the selfishness of the nodes themselves could result in a performance that significantly deviates from the expected one. This review aims at providing the most popular Generic approaches to avoid selfishness in forwarding packets in ad hoc networks. This paper also discusses briefly the applications and issues in ad hoc wireless networks
Evaluation of Antioxidant Activity, Radical Scavenging, and Reducing Power of Clove Oil and Clove Oleoresin in Comparison with Natural and Synthetic Antioxidants in Chevon (Capra aegagrus hircus) and Chicken Meat
The antioxidant effects of clove oil (CO) and oleoresin (OR) in two species of meat i.e. chicken and chevon during refrigerated storage (4±1°C) were investigated. The antioxidant potential (AOP) and radical scavenging activities were compared with natural (α-Tocopherol & L-ascorbic acid) and synthetic antioxidants (BHA & TBHQ). CO & TBHQ, BHA & OR and L-ascorbic acid and α-Tocopherol produced 84-79%, 68-77% and 68-59% AOP respectively in both species. DPPH and ABTS methods of scavenging assay established better scavenging capability of CO and TBHQ in comparison with other treatments. Significant reduction (p<0.05) in FRAP values was observed in CO & TBHQ in both species of meat. The order of antioxidant potential, scavenging activity and reducing power was in the order of CO>TBHQ>OR>BHA>Tocopherol>L-ascorbic acid. All the antioxidant assays analysed demonstrated a very significant correlation (p<0.05) between each other. The results suggest that CO and OR through their antioxidant effects are potentially useful in preserving meat products
Radiation Processing: An Emerging Preservation Technique for Meat and Meat Products
Development of shelf stable meat and meat products is a challenging task due to physico-chemical, microbiological and sensory alterations during storage. Lot of thrust is being given in the application of radiation processing in meat sector due to its microbial safety. Maintaining and delivering quality and safety products both in civilian and service sectors is the need of the hour. Even though irradiation can ensure complete microbial sterility it can lead to lipid and protein oxidation due to the formation of free radicals which can cause flavour changes. Several studies on the usage of natural antioxidants which can arrest these changes have been reported. Irradiation can find excellent applications in the extension of shelf life of chilled and non chilled carcasses and birds in service sectors. There are several radiation processing plants in India commissioned in the private sector which can also be utilized by Armed forces for extending the shelf life of whole carcass and birds with an extension of shelf life. This will be of great significance to the defence forces.
Oblique propagation of arbitrary amplitude electron acoustic solitary waves in magnetized kappa-distributed plasmas
The linear and nonlinear properties of large amplitude electron-acoustic
waves are investigated in a magnetized plasma comprising two distinct electron
populations (hot and cold) and immobile ions. The hot electrons are assumed to
be in a non-Maxwellian state, characterized by an excess of superthermal
particles, here modelled by a kappa-type long-tailed distribution function.
Waves are assumed to propagate obliquely to the ambient magnetic field. Two
types of electrostatic modes are shown to exist in the linear regime, and their
properties are briefly analyzed. A nonlinear pseudopotential type analysis
reveals the existence of large amplitude electrostatic solitary waves and
allows for an investigation of their propagation characteristics and existence
domain, in terms of the soliton speed (Mach number). The effects of the key
plasma configuration parameters, namely, the superthermality index and the cold
electron density, on the soliton characteristics and existence domain, are
studied. The role of obliqueness and magnetic field are discussed.Comment: Submitted to Plasma Physics and Controlled Fusio
An assessment of the coverage of non-communicable disease research reported in British and Irish newspapers, 2002-13
Background: The reporting of medical research in the mass media is often the only way for the general public to learn about it, as most people do not read, nor have access to, scientific papers. Aims: We wished to map non-communicable disease (NCDs) research stories in two UK newspapers, the Daily Mail and The Guardian, and an Irish newspaper, the Irish Times, in 2002–13. Methodology: We identified relevant stories by means of the Factiva database, and obtained details of the cited research papers from the Web of Science. We compared coverage of research on five NCDs with the disease burden, and with the amount of research, in the two countries. We also analysed the sex distribution of the journalists, the researchers whose work was cited and any commentators mentioned in the stories. Results: There were 3921 stories in total (1990 in the Daily Mail, 1127 in the Irish Times, and 804 in The Guardian). Cancer and mental health disorders research attracted most attention. The other NCDs were cardiovascular disease & stroke, diabetes, and respiratory diseases. The stories tended to focus on epidemiological research, and means to reduce the risk of disease, rather than treatment. Both countries over-cited their own research, particularly Ireland. Conclusions: Coverage of the five NCDs tended to mirror the amounts and changes in the disease burden, both in time and between the two countries, notably for dementia and depression. Male researchers and commentators received more attention than females, and so reinforced existing gender stereotypes
Development of compressed meat based bar using response surface methodology
Studies were carried out to optimize the percentage of ingredients for the development of ready to eat mutton bar. Central composite rotatable design of response surface methodology (RSM) was used for designing the experimental combinations. Matrix for compression was designed by selecting factors like mutton powder, binders and applied pressure. Protein percentage, hardness and over all acceptability (OAA) were taken as responses. OAA and hardness showed highly significant and fitted with quadratic model whereas other response i.e. protein levels found to be significant and fitted with linear model. From the design of experiments 45g/100g of mutton powder with 5g/100g binders having an applied pressure of 142 kg/cm2 yielded a bar having a protein percentage of 35g/100g with a hardness of 20.9 N with an overall acceptability score of 8.6 ±0.2 on a 9 point hedonic scale. The product gives energy of 393 kcal per 100 g
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