A Kaluza-Klein Inspired Brans-Dicke Gravity with Dark Matter and Dark Energy Model

We propose the Kaluza-Klein inspired Brans-Dicke gravity model containing possible existence of dark matter and dark energy. The massive scalar field coupled with gravity in 5 dimensional spacetime can be reduced to 4 dimensional gravity along with the dilaton $\phi$, gauge fields $A_{\mu}$, and the tower of scalar fields $\eta_n$. Two additional gauge fields are introduced to form "Cosmic Triad" vector field scenario. We then use the dynamical system approach to analyze the critical points and their corresponding physical parameters. We found that in the case where only the zero mode of the Kaluza-Klein scalar is decoupled, the system contains both dark matter and dark energy phase depending on the mass parameter with the presence of the gauge field.Comment: 29 pages, 2 figure

REVIEW OF AQUACULTURE GENETIC RESEARCHES IN THAILAND

NO ABSTAC

Review of Aquaculture Genetic Researches in Thailand

Aquaculture business has been well established in Thailand for more than 40 years. The most recent data indicated a total production of 260 380 tons. Sixty-five percent of the total production came from coastal aquaculture, mainly tiger prawn (Penaeus monodon) culture. Other important species for coastal aquaculture are banana prawn (P. merguensis), cockle (Anadara granosa), green mussel (Perna viridis), oyster (Crassostrea belcheri, Saccostrea commercialis), sea bass (Lates calcarifer) and grouper (Epinephelus tauvina). Freshwater aquaculture, although produced only 35% of the annual production, provides major protein source for people in rural areas. Important freshwater species are Nile tilapia (Oreochromis niloticus), tawes (Puntius gonionotus), sepat Siam (Trichogasterpectoralis), walking catfish (Glorias spp.), stripped catfish (Pangasius sutchi) and giant freshwater prawn (Macrobrachium rosenbergii). Optimum aquacultural practises, namely stocking density, nutrition requirement and water quality have been obtained in most cultured species. But genetic approach has not been considered, thus resulting in deterioration in economic traits which might be due to excessive inbreeding (reviewed by Uraiwan 1989) and/or negative selection (Wongsangchan 1985). The history of researches on genetics in aquaculture in Thailand started in 1982 when the aquaculture genetic programme in form of a network has been established at the National Inland Fisheries Institute, Department of Fisheries. This programme was supported by the International Development Research Centre (IDRC, Canada) in cooperation with Dalhousie University, Canada (Uraiwan 1989). In the same year a genetic improvement programme aiming at improving economic characters of some economic fish species has been conducted at the Department of Aquaculture, Kasetsart University. Paralelly a course in Fish Genetics has been offered. Since then different approaches of genetics have been applied with final objectives on improving aquaculture production of the country. Researches being conducted are reviewed according to the following fish species

Population genetics of the spotted seahorse (Hippocampus kuda) in Thai waters : implications for conservation

A population genetics approach was used to investigate the genetic diversity of the spotted seahorse (Hippocampus kuda) in Thai waters; specifically, the degree of genetic differentiation and species evolution was inferred from sequence analysis of 353 bp of the mitochondrial (mt)DNA control region. The data were then used to identify discrete populations in Thai waters for effective conservation and management. Spotted seahorses were collected from 4 regions on the east and west coasts of the Gulf of Thailand and a geographically separated region in the Andaman Sea. Of the 101 mtDNA sequences analyzed, 7 haplotypes were identified, 5 of which were shared among individuals from the east and west coasts of the Gulf of Thailand. The remaining haplotypes were restricted to individuals from the Andaman Sea. Nucleotide and haplotype diversities were similar within the Gulf of Thailand samples, whereas diversity was lower in the Andaman Sea sample. Genetic differentiation appeared between pairs of samples from the Gulf of Thailand and Andaman Sea (FST, p &lt; 0.0001). A large genetic variance appeared among the 2 population groups (94.46%, &Phi;CT = 0.94464, p &lt; 0.01). A Neighbor-joining tree indicated that individuals from the Gulf of Thailand and Andaman Sea formed 2 phylogenetically distinct groups, which were segregated into different population-based clades. While results reported here indicate that populations from the Gulf of Thailand and Andaman Sea should be treated as separate conservation units, a larger sample size from the Andaman Sea is required to confirm this genetic partitioning and low level of diversity observed in the present study.<br /

Nonisothermal Thermogravimetric Analysis of Thai Lignite with High CaO Content

Thermal behaviors and combustion kinetics of Thai lignite with different SO3-free CaO contents were investigated. Nonisothermal thermogravimetric method was carried out under oxygen environment at heating rates of 10, 30, and 50°C min−1 from ambient up to 1300°C. Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS) methods were adopted to estimate the apparent activation energy (E) for the thermal decomposition of these coals. Different thermal degradation behaviors were observed in lignites with low (14%) and high (42%) CaO content. Activation energy of the lignite combustion was found to vary with the conversion fraction. In comparison with the KAS method, higher E values were obtained by the FWO method for all conversions considered. High CaO lignite was observed to have higher activation energy than the low CaO coal

Predicting Ash Deposit Tendency in Thermal Utilization of Biomass

In thermochemical utilization of biomass, ash produced during the process is a major problem that can result in decreased performance and increased in difficulty during operation. Preliminary assessment of potential ash related troubles prior to the use of a specific biomass is valuable, even if it is only a general guideline. In this work, tendency of ash slagging, fouling and agglomeration in thermal processing of biomass was evaluated. Reference peered reviewed data including mineral content and fusion temperature of selected biomass ash were used to calculate multiple indicators (base to acid ratio, slagging index, fouling index, agglomeration index, slag viscosity index, and ternary diagram of main biomass ash composition) adopted from coal research. Major ash forming elements (Fe, Ca, Mg, K, Na, Al, Si) were found to be of relevance to ash melting and deposit behavior. For conventional biomass available locally, woody biomass (wood and wood sawdust) may be combusted without slagging or fouling problem, while non-woody biomasses (bark, husk, straw) are highly probable to experience some of these problems. The ash fusibility predictive models for woody and non-woody biomass were found to be effective. Mitigation can then be designed possibly via fuel blending to avoid or minimize the impact of biomass ash related trouble

Performance and Thermoeconomic Analysis of a Biogas Engine Powered Ventilation System for Livestock Building

In this study, a biogas engine powered ventilation fan of a small swine farm was proposed. The research objective was to evaluate performance of, and apply a thermoeconomic analysis to an active ventilation system powered by a small biogas engine. Comparison was made against a gasoline engine and an electric motor. The engine used was a single-cylinder, four-stroke, spark ignited engine with capacity of 118 cm3. The biogas engine was found to be practically able to drive the ventilation fan with acceptable operation over a range of speeds and loads. At null price for biogas, the biogas engine proved to offer the lowest cost per product exergy unit at $0.054/MJ, which was considerably lower than the gasoline engine and electric motor

Manual on application of molecular tools in aquaculture and inland fisheries management. Part 2. Laboratory protocols and data analysis

The aim of this manual is to provide a comprehensive practical tool for the generation and analysis of genetic data for subsequent application in aquatic resources management in relation to genetic stock identification in inland fisheries and aquaculture. The material only covers general background on genetics in relation to aquaculture and fisheries resource management, the techniques and relevant methods of data analysis that are commonly used to address questions relating to genetic resource characterisation and population genetic analyses. No attempt is made to include applications of genetic improvement techniques e.g. selective breeding or producing genetically modified organisms (GMOs). The manual includes two ‘stand-alone’ parts, of which this is the second volume: Part 1 – Conceptual basis of population genetic approaches: will provide a basic foundation on genetics in general, and concepts of population genetics. Issues on the choices of molecular markers and project design are also discussed. Part 2 – Laboratory protocols, data management and analysis: will provide step-by-step protocols of the most commonly used molecular genetic techniques utilised in population genetics and systematic studies. In addition, a brief discussion and explanation of how these data are managed and analysed is also included. This manual is expected to enable NACA member country personnel to be trained to undertake molecular genetic studies in their own institutions, and as such is aimed at middle and higher level technical grades. The manual can also provide useful teaching material for specialised advanced level university courses in the region and postgraduate students. The manual has gone through two development/improvement stages. The initial material was tested at a regional workshop and at the second stage feedback from participants was used to improve the contents