Getting the Measure of Bionics

In this issue of the Journal of Bionics Engineering we start something which is novel in academic publication but which is not at all uncommon in other serial publications. We present, in a series of seven chapters, a book on the interrelations between biology and engineering. It is not a handbook of bionics ( though that might follow) but a series of essays that will bridge the gap between biology and engineering. We hope you will find them entertaining and informative, and that they will reinforce and revise areas of your knowledge,no matter what your entry point into this subject.     

Brain Evolution: Getting Better All the Time?

Recent studies on bats, goats and hominids suggest that some mammalian brains may have undergone dramatic evolutionary reductions in size. These studies emphasise the importance of selective pressures upon mammalian brain evolution and the need to integrate studies of neuroanatomy, neurophysiology and behaviour.     

Getting the Message Over—An Examination of the Teaching of the Genetic Code

Teachers are required to introduce a number of new curriculum initiatives: technological awareness, economic awareness, process science, industry education—and all whilst trying to teach some biology. This article describes a way in which a number of these areas can be delivered starting from a biological base. The project was developed by a team of biology teachers, HE teachers, and technology and health advisers.     

Getting the actin filaments straight: nucleation-release or treadmilling?

The dynamic turnover of actin filaments plays a central role in the locomotion of metazoan cells. Based on results obtained with actin labelled with a caged fluorescent probe, Theriot and Mitchison proposed a 'nucleation-release' model for the fast-moving fish keratocyte, which predicts the existence of short non-oriented filaments in the motile lamellipodium. More recent structural data on keratocyte cytoskeletons do not support this model, but are consistent with the treadmilling of long actin filaments of graded length. Taken together with Theriot and Mitchison's demonstration that the cytoskeleton remains stationary relative to the substrate in the moving keratocyte, the structural data raise the possibility that a lateral flow of filaments plays a role in lamellipodia motility.     

The ‘Goldilocks Zone’: Getting the Measure of Manual Asymmetries

Some studies have shown that manual asymmetries decrease in older age. These results have often been explained with reference to models of reduced hemispheric specialisation. An alternative explanation, however, is that hand differences are subtle, and capturing them requires tasks that yield optimal performance with both hands. Whereas the hemispheric specialisation account implies that reduced manual asymmetries should be reliably observed in older adults, the ‘measurement difficulty’ account suggests that manual asymmetries will be hard to detect unless a task has just the right level of difficulty—i.e. within the ‘Goldilocks Zone’, where it is not too easy or too hard, but just right. Experiment One tested this hypothesis and found that manual asymmetries were only detected when participants performed in this zone; specifically, performance on a tracing task was only superior in the preferred hand when task constraints were high (i.e. fast speed tracing). Experiment Two used three different tasks to examine age differences in manual asymmetries; one task produced no asymmetries, whilst two tasks revealed asymmetries in both younger and older groups (with poorer overall performance in the old group across all tasks). Experiment Three revealed task-dependent asymmetries in both age groups, but highlighted further detection difficulties linked with the metric of performance and compensatory strategies used by participants. Results are discussed with reference to structural learning theory, whereby we suggest that the processes of inter-manual transfer lead to relatively small performance differences between the hands (despite a strong phenomenological sense of performance disparities).     

Racism within the Canadian university: Indigenous students’ experiences

This article extends the investigation and understanding of the impact that everyday racism/microaggressions can have on the academic experience of Indigenous students by examining the racial climate of a major Canadian university to learn about the nature of anti-Indigenous racism. The data from seventeen interviews with students at McMaster University provide a deeper understanding of how Indigenous students perceive and experience racism within the university environment – including levels, impacts and coping mechanisms – and highlight the potential for racism to have a continuing impact on equality and access to education for Indigenous peoples. Subtle, modern racism is playing an active role in the daily lives of Indigenous university students, affecting both their academic and personal success. Despite increasing levels of successful degree completion and the creation of strong support systems, Indigenous students are consistently faced with barriers, including interpersonal discrimination, frustration with the university system and feelings of isolation.     

Getting the message across: how do plant cells exchange macromolecular complexes?

A major pathway for macromolecular exchange in plants involves plasmodesmata (PD), the small pores that connect adjoining cells. This article considers the nature of macromolecular complexes (MCs) that pass through PD and the pathways and mechanisms that guide them to the PD pore. Recent cell-biological studies have identified proteins involved in the directional trafficking of MCs to PD, and yeast two-hybrid studies have isolated novel host proteins that interact with viral movement proteins. Collectively, these studies are yielding important clues in the search for components that compose the plant intercellular MC trafficking pathway. Here, they are placed in the context of a functional model that links the cytoskeleton, chaperones and secretory pathway in the intercellular trafficking of MCs.     

Getting rid of the unwanted: highlights of developments and challenges of biobeneficiation of iron ore minerals—a review

The quest for quality mineral resources has led to the development of many technologies that can be used to refine minerals. Biohydrometallurgy is becoming an increasingly acceptable technology worldwide because it is cheap and environmentally friendly. This technology has been successfully developed for some sulphidic minerals such as gold and copper. In spite of wide acceptability of this technology, there are limitations to its applications especially in the treatment of non-sulphidic minerals such as iron ore minerals. High levels of elements such as potassium (K) and phosphorus (P) in iron ore minerals are known to reduce the quality and price of these minerals. Hydrometallurgical methods that are non-biological involving the use of chemicals are usually used to deal with this problem. However, recent advances in mining technologies favour green technologies, known as biohydrometallurgy, with minimal impact on the environment. This technology can be divided into two, namely bioleaching and biobeneficiation. This review focuses on Biobeneficiation of iron ore minerals. Biobeneficiation of iron ore is very challenging due to the low price and chemical constitution of the ore. There are substantial interests in the exploration of this technology for improving the quality of iron ore minerals. In this review, current developments in the biobeneficiation of iron ore minerals are considered, and potential solutions to challenges faced in the wider adoption of this technology are proposed.     

Getting ready for the marriage market? A comment

This text comments on the article by Lundborg et al. 'Getting ready for the marriage market? The association between divorce risks and investments in attractive body mass among married Europeans' published in July 2007 in this journal. This commentary presents differing results from the original data using multilevel analysis for calculation. The results presented here suggest there is no significant relation between divorce risk and body mass index (BMI) among married individuals in European countries. Therefore, the primary finding of Lundborg et al. (2007) is questioned.     

Getting rid of the cuckoo Cuculus canorus egg: why do hosts delay rejection?

Egg discrimination is well documented in many hosts of avianbrood parasites, but the proximate mechanisms of egg recognitionand rejection decisions are poorly understood. Relevant in thisrespect is the observation that rejectors of parasite eggs oftendelay their response. This delay has implications for understandingmechanisms important for egg recognition and is the main focusof the present study. We investigated experimentally the relativeeffects of egg mimicry and eggshell strength of common cuckooCuculus canorus eggs on the delay in rejection in marsh warblersAcrocephalus palustris. In addition, by video recording hostresponses, we elucidate the proximate mechanisms behind thedelayed rejections. Host nests were experimentally parasitizedwith 3 types of real eggs differing in mimicry and/or eggshellstrength. Both egg mimicry and eggshell strength significantlyaffected the time to rejection, but the effect of mimicry wasdominant. The delayed rejection of mimetic eggs was explainedby the existence of latency to the release of rejection behaviorbecause of recognition problems. Second, when rejection responsetowards mimetic eggs was initiated, it was less intense comparedwith hosts experiencing nonmimetic eggs. Our results are consistentwith the hypothesis that host motivation when confronted withmimetic eggs needs to increase above a certain threshold beforerejection behavior is released, which likely minimizes the riskof recognition errors. An additional component of the delayin rejection as shown by hosts facing nonmimetic eggs was theseemingly inefficient host rejection behavior, probably reflectinglack of previous experience.