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Tropical alluvial soil has distinctive physical characteristics when compared to common sedimentary soils. Ignoring such distinctive characteristics might lead to geotechnical problems that require a thorough re-investigation. Foundation failures have been identified along some river banks of tropical alluvial soil deposits in Sarawak, Malaysia, which were speculated to be due to cyclic loading effects. This paper presents preliminary results on tropical alluvial soil engineering behaviors from simple shear cyclic loading tests. Specimens measuring 50 mm in diameter and 16 mm in height were obtained from three undisturbed samples. They were sheared using an Electro-Mechanical Dynamic Cyclic Simple Shear (EMDCSS) for thirty cycles at three different target displacements. The results showed hysteresis loops, where the shear stress decreases as the cycle increases. Excess pore water pressures develop during shearing, which correspond to the target displacement levels. The damping ratio increases as the shear strain increases but decreases as the cycle increases. The normalized shear modulus decreases as both the shear strain and loading cycle increase. A comparison with previous literature on cohesive soils shows that the tropical alluvial soil has a lower damping ratio and normalized shear modulus, which range from 3.3% to 9% and 0.0004 to 0.01, respectively. The findings indicate that the tropical alluvial soil has a potential reduction in strength when subjected to continuous cyclic loading. The paper provides a better understanding for academics and engineering professionals before conducting design or remedial work in the tropical alluvial soil environment. • Cyclic simple shear tests on tropical alluvial soil showed strength reduction. • Tropical alluvial soil has low normalized shear modulus and damping ratios. • Tropical alluvial soil has distinctive behavior than common sedimentary soils. [ABSTRACT FROM AUTHOR]

Transport is a main concern for people living in rural and remote communities around the world, where the absence of affordable and reliable transport often prevents access to education, health services and employment opportunities. In Sarawak, a state of Malaysia on the island of Borneo, many rural villages experience acute transport poverty. For their basic transport needs, people here rely on informal transport systems based on local social and cultural networks, which provide essential mobility. We apply Polanyi's concept of social embeddedness to explore mobility in this region, people's efforts to develop regional models of entrepreneurship but also the relative marginalisation of remote communities in terms of development and infrastructure provision and the resulting friction between local people, the companies involved in regional resource extraction activities and local government. Based on data collected between 2015 and 2017, we frame informal transport in this region as a form of Indigenous entrepreneurship that can help local communities achieve wider social and economic inclusion. Our research points to a more social type of entrepreneurship and economic practice, in which social relationships and community responsibilities play an important role. Our qualitative approach, including ethnographic methods such as semi-structured interviews and participant observation, underpins the groundedness of our data in the every-day experiences of the people who took part in the research. • The paper investigates the role of informal transport in alleviating transport poverty. • Informal transport is framed as a form of socially embedded Indigenous entrepreneurship. • Social embeddedness of transport supports mobility and encourages grassroots development. • Persisting structural problems limit the effectiveness of grassroots transport strategies. [ABSTRACT FROM AUTHOR]

Abstract: This paper reports the results of an analysis of 508 sub-fossil carpometacarpi of swiftlets (Aves: Apodidae) recovered during archaeological excavations of the Great Cave of Niah in Sarawak, North-western Borneo. The bones date from 48kyBP (ky BP: 103 calibrated years before present [1950]) to 0.35kyBP and provide a means to consider populations of birds (of which one species is a significant commercial interest) in the context of environmental and climatic change in the past, and their responses to recent anthropogenic landscape changes in the present. Biometric analyses and comparative data indicate that the collection contained specimens attributable to the three extant species of swiftlet that currently inhabit the Great Cave: the black-nest swiftlet (Aerodramus maximus), mossy-nest swiftlet (Aerodramus salanganus) and the white-bellied swiftlet (Collocalia esculenta). A subset of 267 identified specimens provides a time series that suggests that the Great Cave and environs have sustained populations of these three species throughout last 48,000years. While changes in the wing length of extant species of swiftlet are known as a function of geographical and altitudinal range, statistical testing of a single character (greatest length of the carpometacarpus) did not indicate changes in wing length in any of the identified species. The findings indicate that the local environs maintained a sufficient abundance of aerial arthropods to support populations of these obligate insectivores and are consistent with studies that suggest that the structural diversity of forest habitats was maintained throughout the late Pleistocene (48kyBP to 11.6kyBP) and Holocene (11.6kyBP to 0.35kyBP). The findings also provide context for the recent declines of the commercially-significant black-nest swiftlet and suggest that this species may be ill-equipped to adapt to recent anthropogenic deforestation of the Niah area. [Copyright &y& Elsevier]

Summary: The oil palm boom has prompted governments and plantation companies to find ways to incorporate customary landholders in large-scale plantation developments. This paper examines the joint-venture model that has been widely promoted in Sarawak, Malaysia. Principal–agent theory is used to analyze the structural relations between the actors in joint-venture projects—the landholders, the government agency that acts as their trustee, and the private investor. The analysis shows that unequal access to information and influence has compromised the stated objectives of the joint-venture schemes, leaving customary landholders vulnerable to significant exploitation and losses. Thus there has been a systematic failure to achieve the anticipated developmental outcomes. [Copyright &y& Elsevier]

This paper reviews quantitative biostratigraphic data from 101 petroleum exploration wells from the Malay, Sarawak and Sabah basins, and places the stratigraphy of each area into a precise chronostratigraphic framework comprising 41 transgressive-regressive depositional packages which are fully defined here. Each package is 'fingerprinted' by foraminiferal, nannofossil and palynological index fossils, and then tied to the global pattern of glacio-eustatic sea level and climate changes based on the global δ18O and δ13C datasets used to calibrate the geological timescale. The result is a tightly constrained chronostratigraphic framework that is applicable from deep to shallow water and is of high accuracy. It is concluded that there is a sedimentation 'pulsebeat' across Southeast Asia, independent of local and regional tectonics, driven by patterns of global climate change. For the Oligocene and Miocene, Antarctic glaciation is the key driver, whereas the Pliocene cycles are mainly driven by the expansion and contraction of Northern Hemisphere glaciers. The new chronostratigraphic framework allows unconformities across Malaysia to be better characterised, and the different classification schemes of seismic "Groups" in Malay and Penyu basins, "Cycles" in offshore Sarawak and "Stages" in offshore western Sabah to be correlated. Also, with a clear understanding of the effect of fluctuating sea levels on the stratigraphy of the region, it is easier to make firm judgments regarding the effect of tectonics. The study also characterises systems tracts from shelf to basin floor using biostatigraphic assemblages, which should help in ground-truthing the architecture of depositional sequences in the region based on seismic. The new framework is proposed as an alternative to the outdated TB scheme of Haq et al. (1988) , widely used to interpret depositional cycles across Sarawak and Sabah. Image 1 • 101 Malaysian exploration wells were studied for Sequence Biostratigraphy. • 41 depositional cycles have been defined from the mid-Oligocene to Pliocene. • Ages are 'fingerprinted' using age-restricted foraminifera, nannofossils and pollen. • Cycles were driven by Antarctic, followed by Arctic ice volume changes. • The study identifies major issues with the 'Haq' and other sea level curves. [ABSTRACT FROM AUTHOR]