The plains of Sumatra and Kalimantan were sparsely populated at the turn of the 19th century (less than 4 inhabitants/km2), and the local population relied mainly on shifting cultivation of upland rice. The introduction of rubber by Dutch private Estates in the 1910's triggered a radical change in the landscape but no fundamental change in farming practices, at least at the beginning, with the ...

Most dentists are educated in rubber dam use in dental school, but there is often disparity between what is taught for various restorative procedures and what is practiced in the private sector. It is a common, although undocumented, belief that few practicing dentists routinely use rubber dam isolation. This study repeated a survey conducted in 1985 evaluating U.S. general dentists' attitudes ...

BACKGROUND This survey study aimed at investigating the frequency of rubber dam use during root canal treatment, identifying influencing factors for not using it by Saudi general dental practitioners (GDPs) and endodontists. It also aimed at identifying measures that increase rubber dam usage. METHODS After obtaining an ethical approval, two pilot studies were conducted on staff members at Ta...

ions and Presentations. The PAC-C3D factory will give each Control one factory for Abstraction creation, and a list (which can be empty) of factories for Presentations creation, corresponding to each kind of existing Presentation on its node. If allowed by its distribution policy, then the Control will ask the Abstraction factory to create a real Abstraction. Next, the Control will ask each Pre...

Existing plant types of rubber tree after planting and available tapping tree were investigated, and there were about 28 rubber plantations with different tapping years of 8 varieties “CATAS7-33-97”, “CATAS8-79”, “CATAS7-20-59”, “PR107”, “RRIM600”, “GT1”, “INA873”, “93-114” in South China. The results showed that there were six kinds of existing plant types of rubber tree after planting of rubb...

We previously reported that the dispersed rubber microparticles in ethylene-propylenediene monomer (EPDM)/polypropylene (PP) thermoplastic vulcanizates (TPVs) are actually agglomerates of rubber nanoparticles. In this study, based on this new understanding of the microstructure of TPV, we further revealed the microstructure-properties relationship of EPDM/PP TPV during dynamic vulcanization, es...

around 80% of the population relies on agriculture, rice being the staple food. topography urges farmers to cultivate upland rice. the chinese interest in rubber latex has stimulated farmers to grow rubber, although the technical knowledge regarding tree management and latex processing is poor. a study was conducted in an area in luang prabang province to examine the suitability of upland rice ...

Jaipur food designed and developed by Dr. P.K. Sethi is second most widely used foot piece in the world after SACH foot (Solid ankle cushion heel). SACH foot was designed for use in colder climate of western countries. The work on culture specific innovation, The Jaipur foot started with the modification of SACH foot. Jaipur foot made up of microcellular rubber and wooden ankle block with iron ...

in the presented work, sulfur concrete and rubber were used for producing functionally graded materials (fgm). the physical and mechanical properties of sulfur concrete and rubber were changed continuously across the thickness. on one side, there was just rubber and, on the other, there was pure sulfur; the properties of each substance were moved to reach another. this kind of material was cons...

OBJECTIVES To examine if the occurrence of different cancers was increased among rubber workers, as the highest known exposures of humans to nitrosamines have occurred in the rubber industry. METHODS A cohort of 8933 rubber workers (hired after 1 January 1950, still active or retired on 1 January 1981 and employed for at least 1 year in one of five study factories) was followed up for mortali...