A workplace design that reduces employee stress and increases employee productivity using environmentally responsible materials

In today’s competitive global environment, employee productivity is an essential element of a company’s success. Employee productivity can be significantly hindered by high levels of stress experienced in the work environment. In addition, poor indoor air quality contributes to deterioration of employee health and well-being, which further reduces productivity. The object of this study was to explore interior design techniques that may reduce employee stress and enhance productivity while using environmentally responsible materials and furnishings. The design paradigm was qualitative, and the research method used was a case study. Specifically, this was an action-research project consisting of a design proposal for an advertising firm in Michigan. The design solution includes elements that increase collaboration and enable teamwork among employees, combined with flexible and ergonomic furniture as a means to enhance productivity. Environmentally responsible material and furnishings were selected to protect the health and well-being of both employees and global ecosystems. The study discusses limitations as to the wider applicability of the approach described herein and proposes recommendations for future works in this area

An axon initial segment is required for temporal precision in action potential encoding by neuronal populations

Central neurons initiate action potentials (APs) in the axon initial segment (AIS), a compartment characterized by a high concentration of voltage-dependent ion channels and specialized cytoskeletal anchoring proteins arranged in a regular nanoscale pattern. Although the AIS was a key evolutionary innovation in neurons, the functional benefits it confers are not clear. Using a mutation of the AIS cytoskeletal protein \beta IV-spectrin, we here establish an in vitro model of neurons with a perturbed AIS architecture that retains nanoscale order but loses the ability to maintain a high NaV density. Combining experiments and simulations we show that a high NaV density in the AIS is not required for axonal AP initiation; it is however crucial for a high bandwidth of information encoding and AP timing precision. Our results provide the first experimental demonstration of axonal AP initiation without high axonal channel density and suggest that increasing the bandwidth of the neuronal code and hence the computational efficiency of network function was a major benefit of the evolution of the AIS.Comment: Title adjusted, no other change

Behavioral Analysis of Cuttlefish Traveling Waves and Its Implications for Neural Control

SummaryTraveling waves (from action potential propagation to swimming body motions or intestinal peristalsis) are ubiquitous phenomena in biological systems and yet are diverse in form, function, and mechanism. An interesting such phenomenon occurs in cephalopod skin, in the form of moving pigmentation patterns called “passing clouds” [1]. These dynamic pigmentation patterns result from the coordinated activation of large chromatophore arrays [2]. Here, we introduce a new model system for the study of passing clouds, Metasepia tullbergi, in which wave displays are very frequent and thus amenable to laboratory investigations. The mantle of Metasepia contains four main regions of wave travel, each supporting a different propagation direction. The four regions are not always active simultaneously, but those that are show synchronized activity and maintain a constant wavelength and a period-independent duty cycle, despite a large range of possible periods (from 1.5 s to 10 s). The wave patterns can be superposed on a variety of other ongoing textural and chromatic patterns of the skin. Finally, a traveling wave can even disappear transiently and reappear in a different position (“blink”), revealing ongoing but invisible propagation. Our findings provide useful clues about classes of likely mechanisms for the generation and propagation of these traveling waves. They rule out wave propagation mechanisms based on delayed excitation from a pacemaker [3] but are consistent with two other alternatives, such as coupled arrays of central pattern generators [3] and dynamic attractors on a network with circular topology [4]

Transitioning from under-resourced schools to university: an application of Schlossberg's transition model to the South African context

A research report submitted in partial fulfillment of the requirements for the degree of MA by coursework and Research Report in the field of Organisational Psychology in the Faculty of Humanities, University of the Witwatersrand, Johannesburg, 15 March 2018The transition from school to university is a process commonly characterised by stress and significant challenge. Ensuring that this transition happens successfully is critical for academic success. The challenges associated with this transition are exacerbated for students from under-resourced environments. It is believed that failure to transition effectively contributes to the high university drop out-rates in South Africa currently. This study explores the individual experience of the under-resourced student’s transition to university through the application of Schlossberg’s (2011) transition theory. This was done with specific focus on Schlossberg’s (2011) 4S System, which focuses on the resources that students’ utilise during a transition. These resources (4 S’s) include situation, self, support and strategies. This model was specifically chosen, as Schlossberg (2011) emphasises the importance of understanding the individual in transition. Participants were obtained through a purposive sampling technique. Interviews were conducted with nine participants from underresourced backgrounds, with an age range of 20 to 23, in different faculties at The University of the Witwatersrand. Thematic Content Analysis was utilised for data analysis. Findings demonstrated the centrality of students’ access to various resources, in the context of their transition to university, as these impacted the transition process. Concurrent stressors including insufficient skill, language barriers and culture shock which were among the factors that compounded participants’ situation. Further, participants’ sense of self was often compromised due to feelings of inferiority and a sense of lack of control. However, some participants demonstrated high self-efficacy and motivation. In terms of support, participants expressed the importance of family, friends and academic staff, and the stress associated in the absence of these support structures. Lastly the exploration of strategies indicated how students used an array of strategies in order to manage the transition. Importantly, the results demonstrated that under-resourced students are not passive victims in the transition to university, but are active agents attempting to negotiate in the processes to which they are exposed. These themes and additional subthemes were explored and considered in the light of previous literature.MT 201

Thomas Hobbes’s Theory of Crime and Punishment

PhDfunded by a three-year Principal’s Studentship awarded by the School of Historyfunded by a three-year Principal’s Studentship awarded by the School of HistoryThis thesis argues that over the course of his political writings Thomas Hobbes developed a complex yet coherent theory of crime and punishment. His account was designed not only as an element of his theory of the state, but also in response to a set of early modern debates concerning the nature of punishment in contractarian political thought. This argument challenges the claims, frequently advanced in the critical literature, that Hobbes was uninterested in the problem of crime, that his account fails to provide his sovereign with a right to punish at all, or that he considered punishment to be a non-civil activity located in a version of the state of nature. I claim by contrast that Hobbes’s accounts of the origins and location of the right to punish, of the purpose of punishment and of the nature of crime demonstrate that Hobbesian punishment is characterised by retained citizenship, due process and legal rights. Hobbes’s theory of political obligation draws a clear distinction between the punishment of criminals within the state, and the treatment of rebels and enemies outside it. As a result Hobbes is able to reconcile his commitment to subjects’ inalienable right to self-defence with a sovereign right to punish criminals. In addition to providing an account of this foundational aspect of Hobbes’s political theory, the thesis uses Hobbes’s discussion of crime to shed light on a number of related aspects of his work. In particular it argues that, once we have properly understood his criminology, we have strong reasons to reject any suggestion that he defends a right of rebellion.Principal's Studentship, School of Histor

Recognizing Facial Slivers

We report here an unexpectedly robust ability of healthy human participants (n = 40) to recognize extremely distorted needle-like facial images, challenging the well-entrenched notion that veridical spatial configuration is necessary for extracting facial identity. In face identification tasks of parametrically compressed internal and external features, we found that the sum of performances on each cue falls significantly short of performance on full faces, despite the equal visual information available from both measures (with full faces essentially being a superposition of internal and external features). We hypothesize that this large deficit stems from the use of positional information about how the internal features are positioned relative to the external features. To test this, we systematically changed the relations between internal and external features and found preferential encoding of vertical but not horizontal spatial relationships in facial representations (n = 20). Finally, we employ magnetoencephalography imaging (n = 20) to demonstrate a close mapping between the behavioral psychometric curve and the amplitude of the M250 face familiarity, but not M170 face-sensitive evoked response field component, providing evidence that the M250 can be modulated by faces that are perceptually identifiable, irrespective of extreme distortions to the face's veridical configuration. We theorize that the tolerance to compressive distortions has evolved from the need to recognize faces across varying viewpoints. Our findings help clarify the important, but poorly defined, concept of facial configuration and also enable an association between behavioral performance and previously reported neural correlates of face perception

Recognizing Facial Slivers

We report here an unexpectedly robust ability of healthy human participants (n = 40) to recognize extremely distorted needle-like facial images, challenging the well-entrenched notion that veridical spatial configuration is necessary for extracting facial identity. In face identification tasks of parametrically compressed internal and external features, we found that the sum of performances on each cue falls significantly short of performance on full faces, despite the equal visual information available from both measures (with full faces essentially being a superposition of internal and external features). We hypothesize that this large deficit stems from the use of positional information about how the internal features are positioned relative to the external features. To test this, we systematically changed the relations between internal and external features and found preferential encoding of vertical but not horizontal spatial relationships in facial representations (n = 20). Finally, we employ magnetoencephalography imaging (n = 20) to demonstrate a close mapping between the behavioral psychometric curve and the amplitude of the M250 face familiarity, but not M170 face-sensitive evoked response field component, providing evidence that the M250 can be modulated by faces that are perceptually identifiable, irrespective of extreme distortions to the face's veridical configuration. We theorize that the tolerance to compressive distortions has evolved from the need to recognize faces across varying viewpoints. Our findings help clarify the important, but poorly defined, concept of facial configuration and also enable an association between behavioral performance and previously reported neural correlates of face perception

Is Robustness To Transformations Driven by Invariant Neural Representations?

Deep Convolutional Neural Networks (DCNNs) have demonstrated impressive robustness to recognize objects under transformations (e.g. blur or noise) when these transformations are included in the training set. A hypothesis to explain such robustness is that DCNNs develop invariant neural representations that remain unaltered when the image is transformed. Yet, to what extent this hypothesis holds true is an outstanding question, as including transformations in the training set could lead to properties different from invariance, e.g. parts of the network could be specialized to recognize either transformed or non-transformed images. In this paper, we analyze the conditions under which invariance emerges. To do so, we leverage that invariant representations facilitate robustness to transformations for object categories that are not seen transformed during training. Our results with state-of-the-art DCNNs indicate that invariant representations strengthen as the number of transformed categories in the training set is increased. This is much more prominent with local transformations such as blurring and high-pass filtering, compared to geometric transformations such as rotation and thinning, that entail changes in the spatial arrangement of the object. Our results contribute to a better understanding of invariant representations in deep learning, and the conditions under which invariance spontaneously emerges

Cholinergic modulation of epileptiform activity in the developing rat neocortex

The effects of carbachol on picrotoxin-induced epileptiform activity and membrane properties of neurons in the developing rat neocortex were examined in an in vitro slice preparation. Intracellular recordings were obtained in layer II–III neurons of slices prepared from rats 9–21 days of age. Epileptiform activity in 9- to 14-day-olds consisted of a sharply rising, sustained (10–30 s) membrane depolarization with superimposed action potentials. Bath application of carbachol (5–50 μM) raised the threshold for evoking epileptiform activity but, when such responses were evoked, their underlying depolarizations were increased in amplitude. Orthodromic stimulation in slices from 15- to 21-day-old animals evoked a prolonged epileptiform burst response that triggered an episode of spreading depression (SD). Carbachol reduced epileptiform responses and suppressed the occurrence of SD. It did not significantly affect the resting membrane potential or the height of the action potential but decreased the rheobase current needed to evoke an action potential and increased the input resistance. All effects of carbachol were antagonized by atropine (1 μM). These results indicate that carbachol has both pre- and postsynaptic effects in the developing neocortex and can significantly modulate neuronal excitability in the immature nervous system