We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.
To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure no-reply@cambridge.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Robots and inertial measurement units (IMUs) are typically calibrated independently. IMUs are placed in purpose-built, expensive automated test rigs. Robot poses are typically measured using highly accurate (and thus expensive) tracking systems. In this paper, we present a quick, easy, and inexpensive new approach to calibrate both simultaneously, simply by attaching the IMU anywhere on the robot’s end-effector and moving the robot continuously through space. Our approach provides a fast and inexpensive alternative to both robot and IMU calibration, without any external measurement systems. We accomplish this using continuous-time batch estimation, providing statistically optimal solutions. Under Gaussian assumptions, we show that this becomes a nonlinear least-squares problem and analyze the structure of the associated Jacobian. Our methods are validated both numerically and experimentally and compared to standard individual robot and IMU calibration methods.
The first demonstration of laser action in ruby was made in 1960 by T. H. Maiman of Hughes Research Laboratories, USA. Many laboratories worldwide began the search for lasers using different materials, operating at different wavelengths. In the UK, academia, industry and the central laboratories took up the challenge from the earliest days to develop these systems for a broad range of applications. This historical review looks at the contribution the UK has made to the advancement of the technology, the development of systems and components and their exploitation over the last 60 years.
All Fire and Emergency Services (FES) personnel must balance FES work with their other responsibilities. Given that women tend to take on a greater responsibility for management of household/domestic activities than men, the on-call component of their FES work may be associated with very different challenges. Despite this, women have rarely been the focus of on-call research.
Aim:
To explore women’s on-call experiences in the FES by examining coping styles and strategies, with the goal of helping to innovate the way women are supported in FES roles.
Methods:
Relevant findings from two studies are included. The first study involved FES personnel from two agencies in Australia (n=24) who participated in a semi-structured interview. The second study was an anonymous online survey to determine work characteristics, sleep, stress, and coping in on-call workers more broadly, with workers from all industries across Australia (n=228) invited to participate.
Results:
Interview data identified two major themes in terms of coping with on-call work. Support (from family, social, and work), planning, and preparation were identified as important in helping women cope in the context of on-call unpredictability. Results from the survey (43% women) showed that on-call workers were an engaged group in terms of their coping, with 67% classified as having a positive coping style and 58% of women indicating that they agreed/strongly agreed with the statement, “I cope well with on-call work.”
Discussion:
Taken together, these data highlight engagement with positive coping by women who do on-call work, including in the FES. Importantly, positive coping strategies, such as talking about emotions, problem-solving, and seeking support have been linked to increased shift work tolerance in other populations. Coping style and strategies represent modifiable variables which could be specifically applied to assist women to manage the unique challenges associated with on-call work in the FES.
Astrophysics Telescope for Large Area Spectroscopy Probe is a concept for a National Aeronautics and Space Administration probe-class space mission that will achieve ground-breaking science in the fields of galaxy evolution, cosmology, Milky Way, and the Solar System. It is the follow-up space mission to Wide Field Infrared Survey Telescope (WFIRST), boosting its scientific return by obtaining deep 1–4 μm slit spectroscopy for ∼70% of all galaxies imaged by the ∼2 000 deg2 WFIRST High Latitude Survey at z > 0.5. Astrophysics Telescope for Large Area Spectroscopy will measure accurate and precise redshifts for ∼200 M galaxies out to z < 7, and deliver spectra that enable a wide range of diagnostic studies of the physical properties of galaxies over most of cosmic history. Astrophysics Telescope for Large Area Spectroscopy Probe and WFIRST together will produce a 3D map of the Universe over 2 000 deg2, the definitive data sets for studying galaxy evolution, probing dark matter, dark energy and modifications of General Relativity, and quantifying the 3D structure and stellar content of the Milky Way. Astrophysics Telescope for Large Area Spectroscopy Probe science spans four broad categories: (1) Revolutionising galaxy evolution studies by tracing the relation between galaxies and dark matter from galaxy groups to cosmic voids and filaments, from the epoch of reionisation through the peak era of galaxy assembly; (2) Opening a new window into the dark Universe by weighing the dark matter filaments using 3D weak lensing with spectroscopic redshifts, and obtaining definitive measurements of dark energy and modification of General Relativity using galaxy clustering; (3) Probing the Milky Way’s dust-enshrouded regions, reaching the far side of our Galaxy; and (4) Exploring the formation history of the outer Solar System by characterising Kuiper Belt Objects. Astrophysics Telescope for Large Area Spectroscopy Probe is a 1.5 m telescope with a field of view of 0.4 deg2, and uses digital micro-mirror devices as slit selectors. It has a spectroscopic resolution of R = 1 000, and a wavelength range of 1–4 μm. The lack of slit spectroscopy from space over a wide field of view is the obvious gap in current and planned future space missions; Astrophysics Telescope for Large Area Spectroscopy fills this big gap with an unprecedented spectroscopic capability based on digital micro-mirror devices (with an estimated spectroscopic multiplex factor greater than 5 000). Astrophysics Telescope for Large Area Spectroscopy is designed to fit within the National Aeronautics and Space Administration probe-class space mission cost envelope; it has a single instrument, a telescope aperture that allows for a lighter launch vehicle, and mature technology (we have identified a path for digital micro-mirror devices to reach Technology Readiness Level 6 within 2 yr). Astrophysics Telescope for Large Area Spectroscopy Probe will lead to transformative science over the entire range of astrophysics: from galaxy evolution to the dark Universe, from Solar System objects to the dusty regions of the Milky Way.
Dural cavernous angiomas are uncommon benign vascular malformations which may present intraoperative difficulties in hemostasis when the diagnosis is not suspected preoperatively. Preoperative diagnosis can be difficult when angiomas show atypical features and share imaging characteristics with other entities.
Methods:
A patient presented with a radiographically aggressive lesion, subsequently identified as a dural cavernous angioma. The lesion is reviewed and its clinical, radiographic, and pathological features are compared with other vascular malformations.
Case report:
A 40-year-old man presented with new onset seizures and an enhancing lesion infiltrating the floor of the right middle cranial fossa. Due to its aggressive radiographic appearance, initial considerations included chondrosarcoma, meningioma or metastasis. Pathological examination, however, revealed the lesion to be a cavernous angioma of dura.
Conclusion:
This uncommon lesion may present a diagnostic challenge with significant intraoperative implications. T2 sequence hyperintensity in a relevant lesion should raise suspicion of an hemangioma. It is important to be aware of this entity and its potential to mimic other entities on radiographic grounds.
Food-based dietary recommendations (FBR) play an essential role in promoting a healthy diet. To support the process of formulating a set of population-specific FBR, a probabilistic model was developed specifically to predict the changes in the percentage of a population at risk of inadequate nutrient intakes after the adoption of alternative sets of FBR. The model simulates the distribution of the number of servings per week from food groups or food items at baseline and after the hypothetical successful adoption of alternative sets of FBR, while ensuring that the population's energy intake distribution remains similar. The simulated changes from baseline in median nutrient intakes and the percentage of the population at risk of inadequate nutrient intakes are calculated and compared across the alternative sets of FBR. The model was illustrated using a hypothetical population of 12- to 18-month-old breast-feeding children consuming a cereal-based diet low in animal source foods.
To investigate the proportion of foods that are unhealthy to which children are exposed at the checkout of convenience supermarkets.
Design
We performed a cross-sectional survey of foodstuffs displayed at the checkout. Products displayed at or below children's eye-level were designated as healthy, unhealthy or unclassifiable using the Food Standards Agency's scoring criteria.
Setting
Thirteen convenience supermarkets from the three leading UK supermarket chains were selected on the basis of proximity to the town hall in Sheffield, England.
Subjects
Convenience supermarkets were defined as branches of supermarket chains that were identified as being other than superstores on their company's store locator website.
Results
In almost all of the convenience supermarkets surveyed, the main healthy product on display was sugar-free chewing gum. On average, when chewing gum was not included as a foodstuff, 89% of the products on display at the checkouts of convenience supermarkets were unhealthy using the Food Standards Agency's criteria. One store was a notable outlier, providing only fruit and nuts at its checkout.
Conclusions
The overwhelming majority of products to which children are exposed at the convenience supermarket checkout are unhealthy. This is despite all the supermarket chains surveyed having signed up to the UK Government's ‘responsibility deal’.
Eimeria is a common genus of apicomplexan parasites that infect diverse vertebrates, most notably poultry, causing serious disease and economic loss. Like all apicomplexans, eimerians have a complex life cycle characterized by asexual divisions that amplify the parasite population in preparation for sexual reproduction. This can be divided into three events: gametocytogenesis, producing gametocytes from merozoites; gametogenesis, producing microgametes and macrogametes from gametocytes; and fertilization of macrogametes by microgametes, producing diploid zygotes with ensuing meiosis completing the sexual phase. Sexual development in Eimeria depends on the differential expression of stage-specific genes, rather than presence or absence of sex chromosomes. Thus, it involves the generation of specific structures and, implicitly, storage of proteins and regulation of protein expression in macrogametes, in preparation for fertilization. In Eimeria, the formation of a unique, resilient structure, the oocyst wall, is essential for completion of the sexual phase and parasite transmission. In this review, we piece together the molecular events that underpin sexual reproduction in Eimeria and use additional details from analogous events in Plasmodium to fill current knowledge gaps. The mechanisms governing sexual stage formation and subsequent fertilization may represent targets for counteracting parasite transmission.
Legal discussions of mercy tend to be messy even though everyone engaged in them accepts the same basic definition of the concept. Mercy is the suspension or reduction of a punishment that is deserved. Writers from every age attach elaborations of their own to test or confirm a specific theory, but the basic definition holds, and it is simple enough. Nothing, however, is simple or even direct the moment the concept is brought into a legal frame of reference.
To deserve a degree of punishment in law has two prongs: the legal stipulation of redress and the moral code in support of it. When stipulation and code cohere, the law proceeds with certainty. When stipulation and code diverge over the endless particularity in deviance, then uncertainty, debate, acrimony, and controversy enter the legal process and create a zone where thoughts of mercy become more prevalent.