Biologically Inspired Feedback Design for Drosophila Flight

We use a biologically motivated model of the Drosophila's flight mechanics and sensor processing to design a feedback control scheme to regulate forward flight. The model used for insect flight is the grand unified fly (GUF) [3] simulation consisting of rigid body kinematics, aerodynamic forces and moments, sensory systems, and a 3D environment model. We seek to design a control algorithm that will convert the sensory signals into proper wing beat commands to regulate forward flight. Modulating the wing beat frequency and mean stroke angle produces changes in the flight envelope. The sensory signals consist of estimates of rotational velocity from the haltere organs and translational velocity estimates from visual elementary motion detectors (EMD's) and matched retinal velocity filters. The controller is designed based on a longitudinal model of the flight dynamics. Feedforward commands are generated based on a desired forward velocity. The dynamics are linearized around this operating point and a feedback controller designed to correct deviations from the operating point. The control algorithm is implemented in the GUF simulator and achieves the desired tracking of the forward reference velocities and exhibits biologically realistic responses

Spontaneous Growth of Gallium-Filled Microcapillaries on Ion-Bombarded GaN

Bottom-up growth of microscopic pillars is observed at room temperature on GaN irradiated with a Ga+ beam in a gaseous XeF2 environment. Ion bombardment produces Ga droplets which evolve into pillars, each comprised of a spherical Ga cap atop a Ga-fille

Shoulder Ulcers in Sows

A literature review was conducted on shoulder ulcers in sows. Shoulder ulcers are caused by pressure that the shoulder blade exerts against tissues that overlie it. Those issues lose blood supply and die. Because the pressure is directed outward, tissue damage occurs before the ulcer is evident on the skin surface. Ulcer prevalence is highly variable; 0 to more than 20% of the sows in 218 herds evaluated had shoulder ulcers. Ulcers usually develop during late gestation and early lactation and many heal shortly after weaning. Numerous risk factors for developing shoulder ulcers have been identified. Inactivity and thin sow body condition seem to be the most important ulcer risk factors. Thus, farrowing caretakers may be able to prevent ulcers by carefully monitoring each sow’s lying behavior and attempting to fix any problem that restricts movement. Checking the gestation and lactation feeding programs to ensure that sows enter the farrowing area in proper body condition also may prevent ulcers. Experience from Denmark indicates a pad fixed to the shoulder of sows at the first sign of redness in the skin may prevent ulcers too. Sows starting to develop an ulcer benefit from treatment of underlying issues that cause inactivity, daily application of a topical disinfectant, early weaning and movement to a hospital pen, or a rubber mat to lie on in the farrowing crate. Close observation and appropriate care of sows especially around the time of farrowing should keep the incidence of shoulder ulcers low in the pork industry

Construction of a conceptualization of personal knowledge within a knowledge management perspective using grounded theory methodology

The current research used grounded theory methodology (GTM) to construct a conceptualization of personal knowledge within a knowledge management (KM) perspective. The need for the current research was based on the use of just two categories of knowledge, explicit and tacit, within KM literature to explain diverse characteristics of personal knowledge. The construct of tacit knowledge has often been explicated and debated in KM literature. The debate over tacit knowledge arose from the complex epistemological roots of tacit knowing and the construct of tacit knowledge popularized by organizational knowledge creation theory. The ongoing debate over tacit knowledge in KM literature has shed little light on personal knowledge within a KM perspective. The current research set aside the debate over tacit knowledge and pursued the construct of personal knowledge from the perspective of the knower using GTM. Thirty-seven interviews were conducted with fourteen participants. Interviews were audio recorded and coding was accomplished with the qualitative data analysis software MAXQDA. A total of eight categories were identified. These were organized into two groups. The core category being overwhelmed represented the absence of personal knowledge. The categories questioning self, seeking help, and microthinking fit under being overwhelmed. Together these categories were inverse indicators because they all decreased as knowledge acquisition progressed. The core category being confident represented the presence of personal knowledge. The categories remembering, multitasking, and speed fit under being overwhelmed. Together these categories were direct indicators because they all increased as knowledge acquisition progressed. Three significant conclusions were drawn from the current research. These conclusions led to the conceptualization of personal knowledge from a KM perspective. The first significant conclusion was the conceptualization of a process of knowing as Integrated Complexity: From Overwhelmed to Confident (ICOC). The second significant conclusion was personal knowing as first-person epistemology is a universally lived experience that includes commitments to internal and external requirements as well as a bias toward integration. The third significant conclusion was personal knowledge can be viewed as a complex adaptive system. Finally, the current research concluded that personal knowledge within a KM perspective is a complex adaptive system maintained through acts of first-person epistemology

Merging DNA metabarcoding and ecological network analysis to understand and build resilient terrestrial ecosystems

Summary 1. Significant advances in both mathematical and molecular approaches in ecology offer unprecedented opportunities to describe and understand ecosystem functioning. Ecological networks describe interactions between species, the underlying structure of communities and the function and stability of ecosystems. They provide the ability to assess the robustness of complex ecological communities to species loss, as well as a novel way of guiding restoration. However, empirically quantifying the interactions between entire communities remains a significant challenge. 2. Concomitantly, advances in DNA sequencing technologies are resolving previously intractable questions in functional and taxonomic biodiversity and provide enormous potential to determine hitherto difficult to observe species interactions. Combining DNA metabarcoding approaches with ecological network analysis presents important new opportunities for understanding large-scale ecological and evolutionary processes, as well as providing powerful tools for building ecosystems that are resilient to environmental change. 3. We propose a novel ‘nested tagging’ metabarcoding approach for the rapid construction of large, phylogenetically structured species-interaction networks. Taking tree–insect–parasitoid ecological networks as an illustration, we show how measures of network robustness, constructed using DNA metabarcoding, can be used to determine the consequences of tree species loss within forests, and forest habitat loss within wider landscapes. By determining which species and habitats are important to network integrity, we propose new directions for forest management. 4. Merging metabarcoding with ecological network analysis provides a revolutionary opportunity to construct some of the largest, phylogenetically structured species-interaction networks to date, providing new ways to: (i) monitor biodiversity and ecosystem functioning; (ii) assess the robustness of interacting communities to species loss; and (iii) build ecosystems that are more resilient to environmental change

Demonstrating the effectiveness of non-metallic riser flange covers for diverting leaks and jet fires using computational fluid dynamics

PresentationThe current oil and gas industry market conditions put greater emphasis of finding cost-effective design solutions while maintaining the same emphasis on process safety. Riser flange covers potentially provide a weight-saving alternative to fire walls between FPSO riser balconies and process modules, but that saving can only be realised if non-metallic materials are employed. Flanges represent the most probable leak point, and the covers are designed to entirely surround the flange and divert any leaks outboard and away from the process equipment. Therefore, any flange cover system has to be capable of resisting and diverting the flow from the largest credible leak. This work demonstrates the application of Computational Fluid Dynamics (CFD) coupled with Finite Element Analysis (FEA) to demonstrate the response of a syntactic phenolic foam and glass reinforced laminate system which combine to provide passive fire protection and thermal insulation. The work outlines a combined analytical approach to demonstrate the effectiveness of this weight-saving system for a high-flow rate gas riser. This paper describes the design of the flange cover and the materials used, the failure case against it was to protect and how that case was simulated, the fluid dynamics of the gas leak within the cover, and the stresses generated within the cover structure

Development and automation of a test of impulse control in zebrafish.

Deficits in impulse control (difficulties in inhibition of a pre-potent response) are fundamental to a number of psychiatric disorders, but the molecular and cellular basis is poorly understood. Zebrafish offer a very useful model for exploring these mechanisms, but there is currently a lack of validated procedures for measuring impulsivity in fish. In mammals, impulsivity can be measured by examining rates of anticipatory responding in the 5-choice serial reaction time task (5-CSRTT), a continuous performance task where the subject is reinforced upon accurate detection of a briefly presented light in one of five distinct spatial locations. This paper describes the development of a fully-integrated automated system for testing impulsivity in adult zebrafish. We outline the development of our image analysis software and its integration with National Instruments drivers and actuators to produce the system. We also describe an initial validation of the system through a one-generation screen of chemically mutagenized zebrafish, where the testing parameters were optimized

Four pillars of heart failure: contemporary pharmacological therapy for heart failure with reduced ejection fraction

The past two decades have heralded dramatic improvements in outcomes for people living with heart failure with reduced ejection fraction (HFrEF).1 The more widespread implementation of disease modifying pharmacological therapies,2 supported by landmark trials of renin-angiotensin system inhibitors3 and beta-blockers4 have improved longevity despite a background of an ageing and increasingly multimorbid population. Although the benefits of comprehensive pharmacological therapies are clear, the real-world attainment of target doses5 6 and utilisation of novel agents such as angiotensin receptor-neprilysin inhibitors (ARNI)7 remain low. Furthermore, HFrEF remains a disease associated with significant morbidity and reduced survival relative to those without HFrEF, even after taking into account comorbidities.8 Recently, trials have demonstrated improved outcomes in people with HFrEF receiving sodium-glucose co-transporter 2 inhibitors (SGLT2i).9 10 However, it is currently unclear how these agents will be used alongside established therapies. Now is therefore an opportune moment to pause and reflect on our current practice, barriers to further progress and how future guidelines might work better for our patients. In this viewpoint we summarise how our current linear approach, on a background of increasingly complex pharmacotherapy has the potential to cause confusion and consequent delays which could lead to even worse attainment of optimal therapies. On the other hand, a more parallel approach to the initiation and optimisation of the Four Pillars of Heart Failure would simplify our approach, yielding benefits for our patients and healthcare systems

Night Matters—Why the Interdisciplinary Field of “Night Studies” Is Needed

The night has historically been neglected in both disciplinary and interdisciplinary research. To some extent, this is not surprising, given the diurnal bias of human researchers and the difficulty of performing work at night. The night is, however, a critical element of biological, chemical, physical, and social systems on Earth. Moreover, research into social issues such as inequality, demographic changes, and the transition to a sustainable economy will be compromised if the night is not considered. Recent years, however, have seen a surge in research into the night. We argue that “night studies” is on the cusp of coming into its own as an interdisciplinary field, and that when it does, the field will consider questions that disciplinary researchers have not yet thought to ask