North Thailand Research Articles

Cancer incidence in the Hmong of Central California, United States, 1987-94.

The Hmong are an ethnic minority in China, some of whom migrated to the mountainous areas of North Vietnam, Laos, and Thailand in the 19th and 20th centuries. Because of their support for the United States during the Vietnam war, many Laotian Hmong fled to Thailand and eventually were re-settled in the US after the end of that conflict. Approximately 100,000 Hmong currently live in the US, of whom about half reside in the Central Valley of California. The purpose of this study was to measure cancer incidence in this unique new immigrant population. Using the resources of the Cancer Registry of Central California (CRCC), a population-based cancer registry, cancer incidence in the Hmong was evaluated by calculating age-adjusted incidence rates as well as by calculating proportional incidence ratios. Compared with all races combined, elevated rates of cancer in the Hmong were observed for the following sites: nasopharynx, stomach, liver, pancreas, leukemia, and non-Hodgkin's lymphoma. Cervical cancer incidence overall was elevated, but more noteworthy, invasive cervix cancer rates were much higher than expected. Lower cancer rates were found for breast, prostate, and colorectal cancer. Hmong also experienced advanced stage and grade of disease at diagnosis for many cancer sites in addition to cervical cancer, which may be explained by cultural factors, including avoidance of Western medical care and low rates of participation in screening programs. This population should be followed closely and monitored for patterns of cancer incidence in the future since it provides a natural laboratory for studies of cancer etiology as this population gradually becomes acculturated to the Western lifestyle.

A new Chaetomium from Thailand

Chaetomium floriforme sp. nov., isolated from unidentified fallen leaves collected in the north of Thailand, is described and illustrated. The fungus is distinguished by its typical obovate ascomata with articular ascomatal hairs, broadly limoniform ascospores with an apical or subapical germ pore, a Humicola anamorph and its growth temperature response.

The mesmerizing wart: the pollination strategy of epiphytic lady slipper orchid Paphiopedilum villosum (Lindl.) Stein (Orchidaceae)

Paphiopedilum villosumwas studied in hill evergreen forests (at up to 35 m above ground level) in North Thailand between 1990 and 1994. Flowering lasted 4·5 months: flower longevity 2–3 months. During 224 hours of flower-watching, less than 100 specimens of Syrphidae (Diptera) were seen in the vicinity of the flowers; 15 cases of pollen acquisition were mainly by femaleEpisyrphus alternans, Syrphus fulvifacies, Betasyrphus serariusamong 6 spp. of pollinators. Populations peaked during the main flower opening period, one month before the maximum number of open flowers was reached in early February. The flowers are ‘kettle-traps’ without known reward, luring mainly by food deception. Long distance attraction is probably by a urine-like odour (attraction to mammalian excretions had hitherto been little reported) and colour contrast. Close range lure is by the glittering staminode (probably mimicking droplets of honeydew/moisture) centred by a slippery wart (faking a perch) at which pollinators fly, immediately losing their grip and tumbling into the pouch, preventing wing action and falling being disrupted by a trough-shaped frame. Escape is up the tunnel, past the stigma, to the exit where, pressed by several mechanisms against the anther, the hoverfly scoops off very sticky pollen which has a viability of at least 8 weeks. Capsule formation averaged 8%.

‘Suture zones’ in peninsular Malaysia and Thailand: implications for palaeotectonic reconstruction of southeast Asia

The existence of one or more long suture zones extending from Thailand to peninsular Malaysia has been widely accepted in almost all palaeotectonic reconstruction of southeast Asia. Geological evidence from the areas where suture zones have been proposed in these two countries are not reconcilable with many of the inferences and interpretations of the geology on which the palaeotectonic models are based. With the possible exception of the Nan-Uttaradit suture in Thailand, the relationship of the other proposed ‘suture’ to subduction processses must be regarded as highly doubtful. Correlating geological belts from north Thailand to southern peninsular Malaysia is extremely difficult, given the present limited state of our knowledge of the geology in these two geologically complex regions. Correlation, based on simple classification of granites and their implied geotectonic setting can be misleading. The timing of the proposed collision event to bring together the Gondwana terrain with the Asian terrain, as envisaged in the popular reconstruction scheme, remains one of the most crucial problem which needs to be addressed by those advocating this concept. Palaeontological, stratigraphical, igneous, metamorphic and structural evidence, which can shed light on this difficult question, give conflicting ages for the major orogenic events in this region.

Integrated Watershed Management Planning and Information Requirements in Northern Thailand

ABSTRACT Increasing water scarcity is being experienced in Thailand leading to more attention being directed to watershed management. This paper describes a project undertaken to assess and organise the information base available for integrated watershed management planning in the north of Thailand. The situation is complicated by the presence of over half a million hilltribe peoples, many of whom cannot produce enough food to survive. Although a considerable amount of watershed management information exists, it is located in many different agencies, is difficult to get access to, is of dubious quality, is very variable in spatial and thematic coverage and is seldom applied to resolve management problems.

Book Reviews

147 Book Reviews Michael R. Rhum, The Ancestral Lords: Gender, Descent and Spirits in a Northern Thai Village. Monograph Series on Southeast Asia, Special Report No. 29. Northern Illinois University: Center for Southeast Asian Studies, 1994. Michael Rhum was one of a number of young scholars doing fieldwork in north Thailand during the early 1980s. They have now become a distinguished cohort in Thai studies. At that time, Rhum was particularly distinguished for his command of the classical languages of Buddhist cultures and of northern Thai. This capability has allowed him to discuss his ethnography against such a classical background.

Molecular evolution of the Alexandrium tamarense ‘species complex’ (Dinophyceae): dispersal in the North American and West Pacific regions

Hypotheses concerning the molecular evolution, population structure and dispersal of the toxic dinoflagellates Alexandrium tamarense (Lebour) Balech, A. catenella (Whedon et Kofoid) Balech and A. fundyense Balech (the ‘tamarensis species complex’) are examined in light of previous reports that compared their small and large-subunit ribosomal RNA gene (SSU and LSU rDNA) sequences. Forty-eight cultures from North America, western Europe, Japan, Australia and Thailand were analysed by a restriction fragment length polymorphism (RFLP) assay of SSU rDNA, and 34 of those by sequencing a fragment of LSU rDNA. Results indicate that the tamarensis species complex comprises at least 5 genetically distinct evolutionary lineages (‘ribotypes’) whose phylogenetic relationships reflect geographic populations, not morphospecies. We believe this pattern reveals a monophyletic radiation from an ancestor that included or gave rise to multiple morphotypes. Accumulated mutations in descendants’ SSU and LSU rDNA are suggested to reflect the prolonged geographic isolation and independent evolution of distinct populations. Novel SSU rDNA data are presented in support of this hypothesis. Given the proposed evolutionary framework and other historical considerations, we interpret the genetic diversity of Japanese A. tamarense/catenella as indicative of dispersed populations from genetically distinct sources. The possibility that A. catenella was introduced to Australia from an Asian source is also considered. In both cases, however, rDNA data alone are insufficient to distinguish whether this occurred thousands of years ago by natural immigrations or as a result of recent human activity (ballast water transport or relays of shellfish stocks). The uncertainty of dispersal timing stems from the relatively slow rate at which rDNA evolves and lack of fossil evidence. Ballast water samples show that viable toxigenic Alexandrium cysts have undergone human-assisted transoceanic transport, illustrating how a region could be ‘seeded’ with genetically distinct A. tamarense and A. catenella from a variety of regional populations.

Clay mineralogy of soils from upper north Thailand

Abstract A total of about 80 soil samples from 20 profiles distributed in Upper North Thailand were examined for the composition of the clay mineralogy. The soils from upland areas consisted of principally kaolinite and those from lowland areas (paddy fields) showed a mixed mineralogy characterized by the presence of kaolinite or illite, or both. Such characteristics of the clay mineralogy were almost the same as those reported so far, and the results are summarized in the APPENDIX. In this report the description deals with which showed some “exceptional” features of clay mineralogical compositions as follows: Mae Suya soil (a Typic Haplustult) which showed randomly mixed layers containing large amounts of illite and illite-vermiculite in addition to kaolinite; Mae Lana Jobo soil (an Oxic Paleustult) which was dominated by gibbsite with considerable amounts of vermiculite and kaolinite; and Khok Yai soil (an Oxic Haplustalf) which was characterized by the presence of mixed layers with large amounts of ill...

Seasonal and Spatial Distribution of 3 Malaria Vectors at Theree Mountainous Villages in North Thailand.

Malaria vector occurrence in mountainous villages was monitored for 2 years in north Thailand. Both larval and adult densities of Anopheles miniumus peaked in May or June and in November or December. Stable conditions in streams during these periods possibly favored the breeding of A n. miniumus. Higher lalval density also was encountered in streams where ca. 3/4 of the water surface was sunlit, portions with rapid currents and slow currents alternate, and the water waS clear. An. maculatus sensu lato peaked in June or July, while An. dirus scarcely changed seasonally. The densities of the three malaria vectors were higher in more mountainous villages.

Seasonal Density and Malaria Vector Competence of Anopheles Monimus and Other Anophelines at a Shallow Valley in North Thailand.

Biting density of anopheline mosquitoes was monitored in both the rainy and dry seasons at 6 outdoor stations in two villages of north Thailand by 3 human and I water buffalo bait. A total of 19 Anopheles was collected. The most predominant species were An. vagus and An. annularis. They were followed by An. hyrcanus group, An. minimus. An. aconitus. An. nivipes and An. kochi. The rest species were not abundant. The fauna of Anopheles changed seasonally. An. minimus. An. aconitus and An. barbirostris were abundant in the dry season, while An. maculatus sensu lato, An. kochi. An. tesselatus. An. vagus. An. annularis and An. hyrcanus group were the rainy season Anopheles. The 'crude feeding index' was relatively high in An. maculatus and An. minimus. They were followed by An. tesselatus and An. splendidus, while that of An. vagus and An. kochi was less than 1/10 of An. minimus. An. minimus was regarded as the most important vector. The biting density of An. minimus was higher at the peripheral area of villages with scarce dwellings and rich vegetation. At stations with dense dwellings and adjoining to an open field, the density of An. minimus was low, and the malaria risk was probably higher.

Characteristics of selected Palaeogene and Cretaceous lacustrine source basins of Southeast Asia

Abstract Lacustrine rift systems have sourced a large portion of the known hydrocarbon reserves in Southeast Asia, and their importance as exploration targets is well established. Our exploration experience has shown that the source rock quality, maturation and the presence of a post-rift marine sag sequence containing reservoirs are the most important factors controlling the hydrocarbon potential of these basins. However, variability in rift architecture, depositional processes, sedimentary geochemistry and thermal history of rift systems is poorly documented in the published literature. Often in the early stages of exploration of rift basins, data available to assess their prospectivity is limited. A more extensive data base of analogues to draw on, particularly non-producing analogues, would allow the explorationist to make better interpretations. In this paper the rift architecture, depositional sequences and sedimentary geochemistry of four Palaeogene and one Cretaceous/Palaeogene graben systems in Indonesia (Sumatra), Thailand and China are described. The graben described are in the Bandar Jaya Basin in South Sumatra, Kampar Kanan Basin in Central Sumatra, Ombilin Basin in West Sumatra, Phetchabun Basin in North Thailand and Dongting Basin in China. These graben cover a range of rift architectures related to wrench tectonic regimes and represent depositional sequences deposited in freshwater to saline lacustrine environments in deep to shallow water lakes. Climatic conditions range from arid in Dongting to tropical throughout Indonesia and Thailand. The geochemical characteristics of the source rocks in these graben are described in the context of their depositional systems.

Some Focal Points of Irrigation Development and Water Management in North and Northeast Thailand

Some Focal Points of Irrigation Development and Water Management in North and Northeast Thailand

The Highland Heritage: Collected Essays on Upland North Thailand

The Highland Heritage: Collected Essays on Upland North Thailand

Eleven of the Largest Developing Countries Are Unlikely to Reach Replacement Fertility by 2015

Using a composite index investigators ranked the prospects of developing countries of reaching replacement fertility by 2015 as either certain probable or unlikely. According to the results among the 37 developing countries ranked only 8 are expected to reach replacement fertility by the year 2015. These include the countries of China Colombia Mexico North Korea South Korea Sri Lanka Taiwan and Thailand. It is noted that although indicators are slightly better for the possible group than for the group none is at a desired level. Hence the caveat is given that although some projections for reaching replacement fertility may seem promising data may be misleading. In a similar study it has been indicated that fertility in 11 of the largest developing countries is unlikely to come anywhere near replacement level by the specified year. The majority of these countries are in sub-Saharan Africa 3 are in Asia and 2 are in the Middle East or North Africa.

Rural people's organizations and agricultural extension in the upper north of thailand: Who benefits?

Recent developments in agricultural extension policy in Thailand emphasise the importance of working with and through local organisations of rural people (RPOs). The paper describes these developments and explores four sets of arguments commonly used to support them: that they will increase the efficiency of extension by reducing the unit cost of “contact” between farmers and extension staff; that they provide a more effective means of enabling farmers, both individually and collectively, to take action in the interests of local agricultural development; that they promote equity in the provision of extension services; and that they can lead to the empowering of rural people to take greater initiative in their own development. Northern Thailand has a long history of the active involvement of local organisations in agricultural development, most notably the independent “muang fai” irrigation associations. The present century has seen a number of government sponsored efforts to promote the formation of new types of RPOs, efforts which have met with mixed success. Research conducted by the Universities of Reading and Chiang Mai in the nine provinces of the upper north identified the varied processes by which RPOs come into being and investigated the relationships between RPOs and extension agencies in the government and voluntary sectors. A series of case studies in different parts of the region provides evidence in support of the above four sets of arguments. These studies also show, however, that current approaches can lead to new patterns of exclusion among the rural population and may lead to a debilitating dependence of newly created RPOs on government or voluntary agencies. The limitations of current approaches are identified and suggestions made for increasing the benefits of RPO-based agricultural extension.

The Highland Heritage: Collected Essays on Upland North Thailand. Edited by Anthony R. Walker. Singapore: Suvarnabhumi Books, 1992. Pp. xvi, 434. Maps, Figures, Tables, Plates, Index.

The Highland Heritage: Collected Essays on Upland North Thailand. Edited by Anthony R. Walker. Singapore: Suvarnabhumi Books, 1992. Pp. xvi, 434. Maps, Figures, Tables, Plates, Index. - Volume 25 Issue 2

The Highland Heritage: Collected Essays on Upland North Thailand. Edited by Anthony R. Walker. Singapore: Suvarnabhumi Press, 1992. xv, 434 pp. $22.80.

The Highland Heritage: Collected Essays on Upland North Thailand. Edited by Anthony R. Walker. Singapore: Suvarnabhumi Press, 1992. xv, 434 pp. $22.80.

Occurrence of paleozoic and early mesozoic radiolaria in Thailand (preliminary report)

Paleozoic and Early Mesozoic radiolarians are newly recovered from chert and associated fine-grained clastic rocks in Thailand. This study clarifies the geologic age of these radiolarian rocks and their paleogeographic and geotectonic significance. Devonian, Early Carboniferous and Permian radiolarians were found in the “Fang Chert” which outcrops along the Chiang Mai-Fang Road, upper north Thailand, Early Carboniferous radiolarians were recovered from a sequence of tuffaceous shale and chert exposed in the Pak Chom area along the Mekong River, and well-preserved Late Devonian and Early Carboniferous radiolarians were also recovered from cherts exposed along the Pak Chom-Loei Road near Phu Laem, north of Loei, in northeast Thailand. These Devonian to Carboniferous radiolarian faunas are apparently identical with those reported from eastern and western Australia. Well-preserved Early Triassic conodonts and radiolarians were obtained from a limeston exposed near Patthalung, southern Thailand. Most of the radiolarian species of this fauna show close affinity with those reported from the Upper Paleozoic rocks, and are new species except for some spicule-type forms. Based on the above-mentioned newly obtained micropaleontological evidence, the geotectonic significance of these radiolarian rocks are briefly discussed in relation to the paleography of the Palaeo-Tethys Ocean, Sibumas and Indochina Terranes, and Australia during the Late Devonian to Middle Permian times.

IGCP 272 - Late Palaeozoic and Early Mesozoic circum-Pacific events and their global correlation

IGCP 203 - Permo-Triassic events of eastern Tethys and their intercontinental correlation - focussed on the Permian-Triassic boundary sequences and in particular there was a consensus that the distinctive biological changes were associated with strong sea-level and tectonic change, strong volcanic activity and a harsh climate. These factors were connected with an important change in the environment and with the exception perhaps of the climate, reflected deep-seated changes within the earth. The project also resulted in improving the physical understanding of the sequences and their biostratigraphy and correlation.IGCP 272 was developed, and was approved in 1988, to apply these results to understanding the Late Palaeozoic and Early Mesozoic and was focussed on the Pacific as integration around this region seemed to offer especially fruitful possibilities.Working group meetings up to the end of 1991 have been held in Australia (Newcastle and Hobart), New Zealand (Dunedin), South America (Sao Paulo and Buenos Aires) and North America (Washington). Meetings are planned in North America, Japan, Eastern Siberia or Thailand and western Europe (France-Spain-Austria).Special cooperation has developed with the Carboniferous, Permian and Triassic Subcommissions of IUGS and with IGCP 214 - Global Bio-events. Using the more exact time correlations developed it has now been possible to show that major geological and biological events (of different levels of significance) are associated with major boundaries already recognized in the World Standard Stratigraphical Time Scale. These comprise the Carboniferous-Permian, the mid-Permian (twofold subdivision, the Permian-Triassic (already recognized in earlier work), the Lower-Middle and Middle-Upper Triassic and the Triassic-Jurassic boundaries.A special achievement of the project has been to show the similar significance of the Midian-Dzhulfian boundary within the Upper Permian but corresponding closely to the traditional Lower-Upper Permian of China and the Middle-Upper Permian of Japan.Although there are also other events at levels which have not been investigated by the project, those outlined all seem to reflect important changes within the earth.

The right to die of a high quadriplegic in a developing country: case report

In the north of Thailand a 21-year-old patient with a complete quadriplegia at C4 level with respiratory insufficiency was treated, including assisted respiration. The patient felt that living held nothing for him and therefore he requested at his own free will to go home and die.