Impact of bacteria and yeast with probiotic properties on performance, digestibility, health status and gut environment of growing pigs in Vietnam

This thesis aimed to evaluate the effects of six lactic acid bacteria (LAB) strains and Bacillus subtilis H4, Saccharomyces boulardii Sb, and a microbial enzyme mixture, supplemented to basal diets on the performance, diet digestibility, health status, and gut environment of growing pigs under Vietnamese conditions. The results showed that three different 3-strain-LAB complexes, comprising combinations of Enterococcus faecium 6H2, Lactobacillus acidophilus C3, Pediococcus pentosaceus D7, L. plantarum 1K8 and L. plantarum 3K2 improved performance, digestibility, health status and gut environment of the LAB-supplemented piglets in the first two weeks post-weaning (Per I), but not in the following 3 weeks (Per II). Adding an LAB strain (L. fermentum NC1) alone or combined with the Bacillus, or combined with a Bacillus and yeast complex, to a 3-strain-LAB complex showed improvements in the performance, diet digestibility, health status and gut environment of the probiotics-supplemented piglets in both Per I and II. The inclusion of Bacillus resulted in higher nutrient digestibility, and the addition of Saccharomyces showed improvements in the scouring scores of the piglets. Supplementation with either a microbial enzyme mixture alone or a combination of a 3-strain-LAB complex and yeast in a weaner diet improved the performance and diet digestibility in piglets in Per I. In Per II, no changes in performance or digestibility were found in enzymes-fed piglets, while improved performance and diet digestibility were obtained in piglets fed the LAB-yeast diet. There was lack of response of piglets to this enzyme mixture when these enzymes were supplemented to the diet that contained the complex of LAB and yeast in both Per I and II. Dietary supplementation with the combination of Bacillus, Saccharomyces and 4-strain-LAB complex had positive effects on performance and digestibility in grower pigs, but not in finisher pigs, while supplementation with the Bacillus alone or combined with Saccharomyces did not affect the performance and digestibility in grower and finisher pigs. The results of these studies suggest that combinations of suitable strains of Bacillus, Saccharomyces and LAB can be used as an alternative to antibiotic feed additives in pig production under the conditions of Vietnam

Monitoring and assessment of macroinvertebrate communities in support of river management in northern Vietnam

The thesis aimed to develop a water quality biological monitoring and assessment based on macro-invertebrates to analyse the status of watercourses and to select sustainable restoration measures in order to support river. The research was carried in the Du river basin in northern Vietnam. Spatial and temporal analysis showed that macro-invertebrate community compositions in the Du river were not only driven by morphological characteristics but also by water quality issues. A relatively small temporal variation was detected that requires no remarkable modifications in the development of a bio-assessment methodology for watercourses in the specific river. Multivariate analyses using CCA and Bray-Curtis cluster analysis provided a similar discrimination between pristine and impacted sites in the Du river basin. Qualitative biotic indices including the BMWP-Viet proved to be appropriate for use in the studied watercourses in Vietnam. The BMWP-Viet could differentiate study sites into classes ranging from very good to very poor ecological conditions. The current BMWP-Viet approach can be useful at an early stage of bio-assessment application in Vietnam. However, this method should be improved by optimising the scoring system for common taxa and development of more robust assessment approaches such as multi-metric indices. Data mining techniques including classification trees and support vector machines were applied to develop predictive models for BMWP-Viet as well as presence/absence of macro-invertebrate taxa (ecological indicators). Optimised models indicate the major environmental variables influencing the presence/absence of macro-invertebrates, which in the mean time also reflect the river characteristics that river managers have to consider in their policy plans. A decision support system, the WFD-Explorer was combined with classification trees to link human activities with the ecological river conditions and analyse the relevance of several restoration options

Hydroquinone-Based Poly(arylene ether)s with Pendent Benzothiazole Or Benzoxazole and 3-sulfonated Phenyl Sulfonyl Groups for Use as Proton Exchange Membranes

A series of hydroquinone-based poly(arylene ether) copolymers, with truly pendent sulfonated phenyl sulfonyl groups and either benzothiazole or benzoxazole groups was synthesized for use as proton exchange membranes (PEM). Two homopolymers series, benzothiazole and benzoxazole based, were prepared via meta activated nucleophilic aromatic substitution polycondensation reactions. Two copolymer series of N-heterocyclic and sulfonated phenyl sulfonyl groups were synthesized via a similar method. The ratio of 3,5-difluoro-3\u27-sulfonated diphenylsulfone to 2-[3,5-bis-(4-hydroxyphenoxy)]benzothiazole or 2-[3,5-bis-(4-hydroxyphenoxy)]benzoxaole was varied to afford ion-exchange capacities ranging from 0.60 to 1.39 meq and 0.62 to 1.42 meq, respectively. Polymers were characterized by gel permeation chromatography (GPC), 13C NMR spectroscopy, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The copolymers displayed low water uptake values, moderate glass transition temperatures (\u3e175°C), and excellent thermal stability in excess of 285°C These materials are promising candidates for use as proton exchange membranes under low relative humidity conditions

The role of exchange rate in supporting trade balance in Vietnam

In this paper, I apply a multivariate Structural Vector Autoregressive (SVAR) and Vector Error correction model (VECM) to analyze short-term and long-term effects of foreign exchange rate on trade balance of Vietnam, using monthly data from 2004-2015. Real effective exchange rate is used to reflect overall performance of Vietnam's currency. The results suggest that in short-term, exchange rate has very limited impacts on trade flows; while in longer horizon, it does not affect imports in either nominal or real terms but has strong effect on nominal exports. To the extent of this research, there is a number of policy implications has been made to support policy makers in Vietnam

Effect of Capital Structure on the Profitability of Plastic and Packaging Companies Listed in Vietnam

Purpose: The study aimed to analyse the impact of capital structure on the profitability of plastic and packaging companies listed on the Vietnam Stock Exchange - VNX (HNX, HoSE and Upcom).   Theoretical framework: The study inherits previous studies on the relationship between capital structure and profitability to determine the capital structure that affects profitability.   Design/methodology/approach: Using Qualitative Research (Synthetic Methods; Statistical methods, description; Inductive and interpretive methods) and quantitative research methods (linear regression methods).   Findings: The author has identified two independent variables that represent a capital structure that strongly affects the profitability of enterprises, including: (1) Short-term debt ratio (STD); (2) Long-term debt ratio (LTL).   Research, practical and social implications: Based on the research results, the author offers several discussions and assessments on the critical role of adjusting the optimal capital structure for plastic and packaging companies, in addition to financial solution recommendations aimed at improving profitability for companies.   Originality/value: Through a study of 30 plastic and packaging manufacturing companies, corresponding to 360 observations in the period of 2010 – 2021

Bivariate modelling of precipitation and temperature using a non-homogeneous hidden Markov model

Aiming to generate realistic synthetic times series of the bivariate process of daily mean temperature and precipitations, we introduce a non-homogeneous hidden Markov model. The non-homogeneity lies in periodic transition probabilities between the hidden states, and time-dependent emission distributions. This enables the model to account for the non-stationary behaviour of weather variables. By carefully choosing the emission distributions, it is also possible to model the dependance structure between the two variables. The model is applied to several weather stations in Europe with various climates, and we show that it is able to simulate realistic bivariate time series

Predicting freshwater habitat conditions by the distribution of macroinvertebrates using artificial neural network

Artificial Neural Networks were used to model the relationship between habitat conditions and macroinvertebrate assemblages in the Queensland river and stream system. The clean water approach was used to determine the relationship between presence and absence of macroinvertebrate taxa and physical predictor variables, studying data from reference sites in near pristine conditions. Trained models were applied to assess habitat conditions of impacted and test sites. The dirty water approach studied interrelationships between physical, chemical and biological processes. Sensitivity analyses were carried out by manipulating the values of input parameters and assessing the resulting changes in outputs. Artificial Neural Networks proved an effective computational approach to support bioassessment.Thesis (M.App.Sc.) -- University of Adelaide, Dept. of Soil and Water, 200

Petrology, geochemistry, and Sr, Nd isotopes of mantle xenolith in Nghia Dan alkaline basalt (West Nghe An): implications for lithospheric mantle characteristics beneath the region

Study of petrological and geochemical characteristics of mantle peridotite xenoliths in Pliocene alkaline basalt in Nghia Dan (West Nghe An) was carried out. Rock-forming clinopyroxenes, the major trace element containers, were separated from the xenoliths to analyze for major, trace element and Sr-Nd isotopic compositions. The data were interpreted for source geochemical characteristics and geodynamic processes of the lithospheric mantle beneath the region. The peridotite xenoliths being mostly spinel-lherzolites in composition, are residual entities having been produced following partial melting events of ultramafic rocks in the asthenosphere. They are depleted in trace element abundance and Sr-Nd isotopic composition. Some are even more depleted as compared to mid-ocean ridge mantle xenoliths. Modelled calculation based on trace element abundances and their corresponding solid/liquid distribution coefficients showed that the Nghia Dan mantle xenoliths may be produced of melting degrees from 8 to 12%. Applying various methods for two-pyroxene temperature- pressure estimates, the Nghia Dan mantle xenoliths show ranges of crystallization temperature and pressure, respectively, of 1010-1044°C and 13-14.2 kbar, roughly about 43km. A geotherm constructed for the mantle xenoliths showed a higher geothermal gradient as compared to that of in the western Highlands (Vietnam) and a conductive model, implying a thermal perturbation under the region. The calculated Sm-Nd model ages for the clinopyroxenes yielded 127 and 122 Ma. If the age is meaningful it suggests that there was a major geodynamic process occurred beneath Western Nghe An in the middle- Early Cretaceous that was large enough to cause perturbation in the evolutional trend of the Sm-Nd isotopic system.ReferencesAn A-R., Choi S.H., Yu Y-g., Lee D-C., 2017. Petrogenesis of Late Cenozoic basaltic rocks from southern Vietnam. Lithos, 272-273 (2017), 192-204.Anders E., Grevesse N., 1989. Abundances of the elements: meteorite and solar. Geochimica et Cosmochimica Acta, 53, 197-214.Anderson D.L, 1994. The subcontinental mantle as the source of continental flood basalts; the case against the continental lithosphere mantle and plume hear reservoirs. Earth and Planetary Science Letter, 123, 269-280.Arai S., 1994. Characterization of spinel peridotites by olivine-spinel compositional relationships: review and interpretation. Chemical Geology, 113, 191-204.Ballhaus C., Berry R.G., Green D.H., 1991. High pressure experimental calibration of the olivine orthopyroxene-spinel oxygen geobarometer: implications for the oxidation state of the upper mantle. Contributions to Mineralogy and Petrology, 107, 27-40.Barr S.M. and MacDonald A.S., 1981. Geochemistry and geochronology of late Cenozoic basalts of southeast Asia: summary. Geological Society of America Bulletin, 92, 508-512.Brey G.P., Köhler T., 1990. Geothermobarometry in four-phase lherzolite II. New thermobarometers, and practical assessment of existing thermobarometers. Journal of Petrology, 31, 1353-1378.Briais A., Patriat P., Tapponnier P., 1993. Updated interpretation of magnetic anomalies and seafloor spreading stages in the South China Sea, implications for the Tertiary tectonics of SE Asia. Journal of Geophysical Research, 98, 6299-6328.Carlson R.W., Irving A.J., 1994. Depletion and enrichment history of subcontinental lithospheric mantle: an Os, Sr, Nd and Pb isotopic study of ultramafic xenoliths from the northwestern Wyoming Craton. Earth and Planetary Science Letters, 126, 457-472.Carlson R.W., Lugmair G.W., 1979. Sm-Nd constraints on early lunar differentiation and the evolution of KREEP. Earth and Planetary Science Letters, 45, 123-132.Carlson R.W., Lugmair G.W., 1981. Sm-Nd age of lherzolite 67667: implications for the processes involved in lunar crustal formation. Earth and Planetary Science Letters, 56, 1-8.Choi H.S., Mukasa S.B., Zhou X-H., Xian X-G.H., Andronikov A.V., 2008. Mantle dynamics beneath East Asia constrained by Sr, Nd, Pb and Hf isotopic systematics of ultramafic xenoliths and their host basalts from Hannuoba, North China. Chemical Geology, 248, 40-61.Choi S.H., Jwa Y.-J., Lee H.Y., 2001. Geothermal gradient of the upper mantle beneath Jeju Island, Korea: evidence from mantle xenoliths. Island Arc, 10, 175-193.Choi S.H., Kwon S-T., Mukasa S.B., Sagon H., 2005. Sr-Nd-Pb isotope and trace element systematics of mantle xenoliths from Late Cenozoic alkaline lavas, South Korea. Chemical Geology, 22, 40-64.Cox K.G., Bell J.D., Pankhurst R.J., 1979. The Interpretation of Igneous Rocks. George Allen Unwin.Cung Thuong Chi, Dorobek S.L., Richter C., Flower M., Kikawa E., Nguyen Y.T., McCabe R., 1998. Paleomagnetism of Late Neogene basalts in Vietnam and Thailand: Implications for the Post-Miocene tectonic history of Indochina. In: Flower M.F.J., Chung, S.L., Lo, C.H., (Eds.). Mantle Dynamics and Plate Interactions in East Asia. Geodynamics Ser, American Geophysical Union, 27, 289-299.De Hoog J.C.M., Gall L., Cornell D.H., 2010. Trace-element geochemistry of mantle olivine and application to mantle petrogenesis and geothermobarometry. Chemical Geology, 270, 196-215.DePaolo D. J., 1981. Neodymium isotopes in the Colorado Front Range and crust - mantle evolution in the Proterozoic. Nature, 291, 193-197.DePaolo D.J., Wasserburg G.J., 1976. Nd isotopic variations and petrogenetic models. Geophysical Research Letters, 3(5), 249-252. Doi: https://doi.org/10.2113/gselements.13.1.11.Embey-Isztin A., Dobosi G., Meyer H.-P., 2001. Thermal evolution of the lithosphere beneath the western Pannonian Basin: evidence from deep-seat xenoliths. Tectonophysics, 331, 285-306.Fedorov P.I., Koloskov A.V., 2005. Cenozoic volcanism of Southeast Asia. Petrologiya, 13(4), 289-420.Frey F.A., Prinz M., 1978. Ultramafic inclusions from San Carlos, Arizona: Petrologic and geochemical data bearing on their Petrogenesis. Earth and Planetary Science Letters, 38, 129-176.Garnier V., Ohmenstetter D., Giuliani G., Fallick A.E., Phan T.T., Hoang Q.V., Pham V.L., Schawarz D., 2005. Basalt petrology, zircon ages and sapphire genesis from Dak Nong, southern Vietnam. Mineralogical Magazine, 69(1), 21-38.Gast P.W., 1968. Trace element fractionation and the origin of tholeiitic and alkaline magma types. Geochimica et Cosmochimica Acta, 32, 1057-1086.Gorshkov A.P, Ivanenko A.N., Rashidov V.A., 1984. Hydro-magnetic investigations of submarine volcanic zones in the marginal seas of Pacific Ocean (Novovineisky and Bien Dong seas). Pacific Ocean Geology, 1, 13-20.Gorshkov A.P., 1981. Investigation of submarine volcanoes during the 10th course of scientific research vessel ‘Volcanolog’. Volcanology and Seismology, 6, 39-45 (in Russian).Hart S.R., 1988. Heterogeneous mantle domains: signatures, genesis and mixing chronologies. Earth and Planetary Science Letters, 90, 273-296.Hirose K., Kushiro I., 1993. Partial melting of dry peridotites at high pressures: determination of composition of melts segregated from peridotite using aggregate of diamond. Earth Planet Science Letters, 114, 477-489.Hoang-Thi H.A., Choi S.H., Yongjae Yu Y-g., Pham T.H., Nguyen K.H., Ryu J-S., 2018. Geochemical constraints on the spatial distribution of recycled oceanic crust in the mantle source of late Cenozoic basalts, Vietnam. Lithos, 296-299 (2018), 382-395.Izokh A.E., Smirnov S.Z., Egorova V.V., Tran T.A., Kovyazin S.V., Ngo T.P., Kalinina V.V., 2010. The conditions of formation of sapphire and zircon in the areas of alkali-basaltoid volcanism in Central Vietnam. Russian Geology and Geophysics, 51(7), 719-733.Johnson K.T., Dick H.J.B. and Shimizu N., 1990. Melting in the oceanic upper mantle: An ion microprobe study of diopsides in abyssal peridotites. Journal of Geophysical Research (solid earth), 95, 2661-2678.Kölher T.P., Brey G.P., 1990. Calcium exchange between olivine and clinopyroxene calibrated as a geothermobarometer for natural peridotites from 2 to 60 kb with applications. Geochimica et Cosmochimica Acta, 54(9), 2375-2388.Kushiro I., 1996. Partial melting of a fertile mantle peridotite at high pressure: An experimental study using aggregates of diamond. In: A. Basu and S.R. Hart (Eds.), Earth Processes: Reading the Isotopic Code. AGU Monograph, 95, 109-122.Kushiro I., 1998. Compositions of partial melts formed in mantle peridotites at high pressures and their relation to those of primitive MORB. Physics of Earth and Planetary Interiors, 107, 103-110.Latin D., White N., 1990. Generating melt during lithospheric extension: Pure shear vs. simple shear. Geology, 18, 327-331.Lee T.-y. and Lawver L., 1995. Cenozoic plate reconstruction of Southeast Asia. In: M.F.J. Flower, R.J. McCabe and T.W.C. Hilde (Editors), Southeast Asia Structure, Tectonics, and Magmatism. Tectonophysics, 85-138.Li C-F., et al., 2015. Seismic stratigraphy of the central South China Sea basin and implications for neotectonics. Journal of Geophysical Research (solid earth), 120, 1377-1399. Doi:10.1002/2014JB011686.Li C.-F., et al., 2014. Ages and magnetic structures of the South China Sea constrained by deep tow magnetic surveys and IODP Expedition 349 Geochemistry, Geophysics, Geosystems, 14, 4958-4983.Malinovsky A.I., Rashidov V.A., 2015. Compositional characteristics of sedimentary and volcano-sedimentary rocks of Phu Quy-Catwick island group in the continental shelf of Vietnam. Bulletin of Kamchatka Regional Association of ‘Educational - Scientific’ Center, Earth Sciences, 27(3), 12-34 (in Russian with English summary).McCulloch M.T., Wasserburg G.J., 1978. Sm-Nd and Rb-Sr chronology of continental crust formation. Science, 200(4345), 1003-1011.Menzies M.A., Arculus R.L., Best M.G., et al., 1987. A record of subduction process and within-plate volcanism in lithospheric xenoliths of the southwestern USA. In P.H. Nixon (Editor), Mantle Xenoliths, John Wiley Sons, Chichester, 59-74.Nguyen Hoang, Ogasawara M., Tran Thi Huong, Phan Van Hung, Nguyen Thi Thu, Cu Sy Thang, Pham Thanh Dang, Pham Tich Xuan, 2014. Geochemistry of Neogene Basalts in the Nghia Dan district, western Nghe An. J. Sci. of the Earth, 36, 403 -412.Nguyen Kinh Quoc, Nguyen Thu Giao, 1980. Cenozoic volcanic activity in Viet Nam. Geology and Mineral Resources, 2, 137-151 (in Vietnamese with English abstract).Nixon P.H., 1987 (Editor). Mantle xenoliths. John Wiley and Sons, 844p.Norman M.D. and Garcia M.O., 1999. Primitive magmas and source characteristics of the Hawaiian plume: petrology and geochemistry of shield picrites. Earth and Planetary Science Letters, 168, 27-44.Pollack H.N., Chapman D.S., 1977. On the regional variation of heat flow, geotherms and lithospheric thickness. Tectonophysics, 38, 279-296.Putirka K., 2008. Thermometers and Barometers for Volcanic Systems. In: Putirka, K., Tepley, F. (Eds.), Minerals, Inclusions and Volcanic Processes, Reviews in Mineralogy and Geochemistry, Mineralogical Soc. Am., 69, 61-120. Putirka K.D., 2017. Down the craters: where magmas stored and why they erupt. Methods and Further Reading. Supplement to February 2017 issue of Elements, 3(1), 11-16.Putirka K.D., Johnson M., Kinzler R., Longhi J., Walker D., 1996. Thermobarometry of mafic igneous rocks based on clinopyroxene-liquid equilibria, 0-30 kbar. Contributions to Mineralogy and Petrology, 123, 92-108. Putirka K.D., Mikaelian H., Ryerson F., Shaw H., 2003. New clinopyroxene-liquid thermobarometers for mafic, evolved, and volatile-bearing lava compositions, with applications to lavas from Tibet and the Snake River Plain, Idaho. American Mineralogist, 88, 1542-1554. Qi Q., Taylor L.A., Zhou X., 1995. Petrology and geochemistry of mantle peridotite xenoliths from SE China. Journal of Petrology, 36, 55-79.Sachtleben T.H., Seck H.A., 1981. Chemical control on the Al-solubility in orthopyroxene and its implications on pyroxene geothermometry. Contributions to Mineralogy and Petrology, 78, 157-65.Shaw D.M., 1970. Trace element fractionation during anataxis. Geochimica et Cosmochimica Acta, 34, 237-243.Sun S-S, McDonough W.F., 1989. Chemical and isotopic systematics of oceanic basalts: implications for mantle composition and processes. In Saunders A.D. and Norry, M.J. (eds) Magmatism in the Ocean Basins. Geological Society Special Publication, 42, 313-345.Takahashi E., 1986. Melting of a dry peridotite KLB-1 up to 14 Gpa: implications on the origin of peridotite upper mantle. J. Geophysical Research, 91, 9367-9382.Takahashi E., Kushiro I., 1983. Melting of a dry peridotite at high pressure and basalt magma genesis. American Mineralogist, 68, 859-879.Tamaki K., 1995. Upper mantle extrusion tectonics of southeast Asia and formation of western Pacific backarc basins. In: International Workshop: Cenozoic Evolution of the Indochina Peninsula, Hanoi/Do Son, April, p.89 (Abstract with Programs).Tapponnier P., Lacassin R., Leloup P.H., Shärer U., Dalai Z., Haiwei W., Xiaohan L., Shaocheng J., Lianshang Z., Jiayou Z., 1990. The Ailao Shan/Red River metamorphic belt: Tertiary left-lateral shear between Indochina and South China. Nature, 343(6257), 431-437.Tapponnier P., Peltzer G., La Dain A.Y., Armijo R., Cobbold P., 1982. Propagating extrusion tectonics in Asia: New insights from simple experiments with plasticine. Geology, 7, 611-616.Tatsumoto M., Basu A.R., Huang W., Wang J., Xie G., 1992. Sr, Nd, and Pb isotopes of ultramafic xenoliths in volcanic rocks of eastern China: enriched components EMI and EMII in subcontinental lithosphere. Earth Planet Sci. Letters, 113, 107-128.Taylor S.R., McLennan S.M., 1981. The composition and evolution of the continental crust: rare earth element evidence from sedimentary rocks. Philosophical Transactions of the Royal Society of London, 301, 381-399.Tu K., Flower M.F.J., Carlson R.W., Xie G-H., 1991. Sr, Nd, and Pb isotopic compositions of Hainan basalt (south China): Implications for a subcontinental lithosphere Dupal source. Geology, 19, 567-569.Tu K., Flower M.F.J., Carlson R.W., Xie G-H., Zhang M., 1992. Magmatism in the South China Basin 1. Isotopic and trace-element evidence for an endogenous Dupal component. Chemical Geology, 97, 47-63.Warren J.M., 2016. Global variations in abyssal peridotite compositions. Lithos, 248-251, 193-219.Webb S.A., Wood B.J., 1986. Spinel pyroxene- garnet relationships and their dependence on Cr/Al ratio. Contributions to Mineralogy and Petrology, 92, 471-480.Wells P.R.A., 1977. Pyroxene thermometry in simple and complex systems. Contributions to Mineralogy and Petrology, 62, 129-139.Whitford-Stark J.L., 1987. A survey of Cenozoic olcanism on mainland Asia, special paper, 213. Geological Society of America, 74p.Workman R.K., Hart S.R., 2005. Major and trace element composition of the depleted MORB mantle (DMM). Earth and Planetary Science Letters, 231, 53-72.Zhou P., Mukasa S., 1997. Nd-Sr-Pb isotopic, and major- and trace-element geochemistry of Cenozoic lavas from the Khorat Plateau, Thailand, sources and petrogenesis. Chemical Geology, 137, 175-193.Zindler A., Hart S.R., 1986. Chemical geodynamics. Annual Review of Earth and Planetary Sciences, 14, 493-571