Turning waste to wealth-biodegradable plastics polyhydroxyalkanoates from palm oil mill effluent – a Malaysian perspective

Palm oil industries have been contributing significantly towards the country’s economy and increase standard of living among Malaysians. However, it has also been identified as the major contributor for discharging the largest pollution load throughout the country. Owing to high biochemical oxygen demand (BOD) and chemical oxygen demand (COD), the palm oil mill effluent (POME) cannot be discharged directly into the environment. Thus, palm oil industries are facing tremendous challenges in order to comply with environmental regulations. While anaerobic digestion has been employed by most mills as primary treatment, POME can also be a potential source of degradable organic material which can be converted into value-added products and fine chemicals. Organic acids generated during acid-phase anaerobic digestion of POME could be a potential carbon source for the production of polyhydroxyalkanoates (PHA)- a biodegradable thermoplastic material of microbial origin. This paper aims at understanding how organic acids from POME may serve as a renewable feedstock for the biosynthesis of PHA.     

Pinch analysis approach to carbon-constrained planningfor sustainable power generation

A graphical pinch-based methodology for planning retrofits for carbon capture and storage (CCS) in the power generation sector is presented in this work. CCS is widely seen as one of the essential interim technologies to mitigate greenhouse gas emissions, while still being able to utilize fossil fuels, which are relatively inexpensive and reliable in comparison to inherently low-carbon renewable resources. However, retrofitting power plants for CCS entails major capital costs as well as a reduction of thermal efficiency and power output. Thus, it is essential for planning purposes to implement the minimal extent of CCS retrofit that meets the sectoral carbon footprint targets. At the same time, it is necessary to plan for additional power generation capacity or efficiency enhancements to compensate for energy losses resulting from CCS retrofits. The simple graphical approach used in this paper is designed to determine such targets, and shares the same intuitive, insight-driven characteristics of pinch analysis techniques. A case study is shown to illustrate the methodology.     

Abnormalities of the foetal cerebral cortex

Prenatal ultrasound has concentrated on readily visible cerebral structures including head size, shape, ventricles, CSP (cavum septi pellucidi), cerebellar size/vermian presence and cisterna magna. However, apart from these easily visible structures it is important to evaluate the brain itself. Patients who initially appear to have mild isolated findings such as borderline ventriculomegaly in fact can have many more subtle findings that significantly alter prognosis and management that can be detected on detailed examination of the brain. There has been rapid evolution in imaging these foetuses, especially with neurosonography and MRI, and a revolution in understanding the underlying genetic and biochemical mechanisms. There is increasing emphasis to detect cortical abnormalities as early as possible. This article reviews development of the cerebral cortex, the classification, aetiologies and clinical manifestations of cortical disorders, normal and abnormal appearances at ultrasound and MRI, and approaches to investigation. Copyright © 2009 John Wiley & Sons, Ltd.     

Interagency Resource Teams: a Model for Collaborative Approaches to Environmental Education

Abstract: The Undergraduate Interagency Resource Teams at the White Mountain Research Station of the University of California were created in 1994 to support resource-agency mandates and academic research objectives by providing qualified students who can learn, apply, and improve research and agency monitoring protocols. Drawing from documented elements of other successful internship programs, we identified four basic components that we believe may enhance the potential success of the interns: (1) self-directed learning methodologies, (2) multidisciplinary approaches to science, (3) reflection on and documentation of intern learning, and (4) principles of a positive work environment, including teamwork, conflict resolution, and effective communication. During a 10-week summer session, the Interagency Resource Teams expose approximately 17 students to the professional worlds of natural resource agencies and research scientists. In this environment, we have also observed that the internship program not only exposes students to resource management careers but may also help bridge the gap between resource agency specialists and academic researchers.     

Effects of early auditory experience on the development of local song preference in female swamp sparrows

A growing number of studies show that learning about male mating signals can shape the way females discriminate among males and may influence the evolution of both female preferences and the male traits under selection. Female songbirds commonly prefer local songs over foreign songs from a different population. In some species, however, the extent of variation among songs sung by different males within a population is as great as the variation observed between populations, raising the question of how females are able to discriminate local from foreign songs. Here, we report that laboratory-reared female swamp sparrows (Melospiza georgiana) not only show a preference for the particular song types with which they were tutored as compared with both foreign songs and unfamiliar local songs but also show preference for unfamiliar local songs over unfamiliar foreign songs. An acoustic analysis comparing tutor songs and those presented as unfamiliar local and foreign songs suggests that female swamp sparrows might be attuned to the specifics of local note phonology when assessing the attractiveness of unfamiliar songs. Our results demonstrate that early auditory experience influences response to geographic song variation in female swamp sparrows, and suggest the possibility that female songbirds may generalize what they learn from songs early in life to novel songs heard in adulthood. Additional work is needed to evaluate the contribution of unlearned predispositions for local song.     

Mapping species distributions in one dimension by non-homogeneous hidden Markov models: the case of freshwater pearl mussels in the River Dee

The investigation of species distributions in rivers involves data which are inherently sequential and unlikely to be fully independent. To take these characteristics into account, we develop a Bayesian hierarchical model for mapping the distribution of freshwater pearl mussels in the River Dee (Scotland). At the top of the hierarchy the likelihood is used to describe the sequence of sites in which mussels were observed or not. Given that false observations can occur, and that “not observed” means both that the species was not present and that it was not observed, a Markov prior is introduced at the second level of the hierarchy to represent the sequence of sites in which mussels are estimated to occur. The Markov prior allows modelling the spatial dependency between neighbouring sites. A third level in the hierarchy is given by the representation of the transition probabilities of the Markov chain in terms of site-specific explanatory variables, through a logistic regression. The selection of the explanatory variables which influence the Markov process is performed by means of a simulation-based procedure, in the complex case of association between covariates. Four features were found to be associated with reduced chance of finding a local mussel population: tributaries, bridges, dredging, and waste water treatment works. These results complement the results of a previous study, providing new evidence for the causes of the deterioration of a highly threatened species.     

Finding a good job: Academic network centrality and early occupational outcomes in management academia

The impact of universalistic versus particularistic criteria on academic hiring has been receiving growing attention in recent years. Yet, most studies conducted on hiring norms in academy and management academy have ignored the impact of social capital, particularly structural social capital, a particularistic attribute, on occupational outcomes. This could lead to a partial if not misleading view of the sociology of hiring in management academy. We utilize a novel approach, focusing on academic departments' structural social capital in the form of network centrality (based on cumulative PhD exchange networks), and explore how this type of centrality impacts job seekers' occupational prestige for new academic jobs in management departments and early career quality publications. We find that although merit‐based criteria such as publications matter somewhat, academic network centrality explains significant variance in obtaining prestigious jobs. Paradoxically, we find that academic network centrality does not explain early career publications. We discuss the implications of our findings for management science. Copyright © 2011 John Wiley & Sons, Ltd.