2,694 research outputs found

    Beef Cattle Instance Segmentation Using Fully Convolutional Neural Network

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    In this paper we present a novel instance segmentation algorithm that extends a fully convolutional network to learn to label objects separately without prediction of regions of interest. We trained the new algorithm on a challenging CCTV recording of beef cattle, as well as benchmark MS COCO and Pascal VOC datasets. Extensive experimentation showed that our approach outperforms the state-of-the-art solutions by up to 8% on our data

    Bootstrapping Labelled Dataset Construction for Cow Tracking and Behavior Analysis

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    This paper introduces a new approach to the long-term tracking of an object in a challenging environment. The object is a cow and the environment is an enclosure in a cowshed. Some of the key challenges in this domain are a cluttered background, low contrast and high similarity between moving objects - which greatly reduces the efficiency of most existing approaches, including those based on background subtraction. Our approach is split into object localization, instance segmentation, learning and tracking stages. Our solution is benchmarked against a range of semi-supervised object tracking algorithms and we show that the performance is strong and well suited to subsequent analysis. We present our solution as a first step towards broader tracking and behavior monitoring for cows in precision agriculture with the ultimate objective of early detection of lameness

    The physical gravitational degrees of freedom

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    When constructing general relativity (GR), Einstein required 4D general covariance. In contrast, we derive GR (in the compact, without boundary case) as a theory of evolving 3-dimensional conformal Riemannian geometries obtained by imposing two general principles: 1) time is derived from change; 2) motion and size are relative. We write down an explicit action based on them. We obtain not only GR in the CMC gauge, in its Hamiltonian 3 + 1 reformulation but also all the equations used in York's conformal technique for solving the initial-value problem. This shows that the independent gravitational degrees of freedom obtained by York do not arise from a gauge fixing but from hitherto unrecognized fundamental symmetry principles. They can therefore be identified as the long-sought Hamiltonian physical gravitational degrees of freedom.Comment: Replaced with published version (minor changes and added references

    A multi-object spectral imaging instrument

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    We have developed a snapshot spectral imaging system which fits onto the side camera port of a commercial inverted microscope. The system provides spectra, in real time, from multiple points randomly selected on the microscope image. Light from the selected points in the sample is directed from the side port imaging arm using a digital micromirror device to a spectrometer arm based on a dispersing prism and CCD camera. A multi-line laser source is used to calibrate the pixel positions on the CCD for wavelength. A CMOS camera on the front port of the microscope allows the full image of the sample to be displayed and can also be used for particle tracking, providing spectra of multiple particles moving in the sample. We demonstrate the system by recording the spectra of multiple fluorescent beads in aqueous solution and from multiple points along a microscope sample channel containing a mixture of red and blue dye

    A unique case of a malignant sertoli cell tumour with cutaneous metastasis

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    Pure Sertoli cell tumours (SCTs) represent less than 1% of testicular neoplasms and malignant forms are rare. We present a unique case of a 69-year-old man who initially underwent inguinal orchidectomy for a malignant SCT. He then subsequently developed a paraumbilical cutaneous lesion which was histologically identical to the primary tumour. SCTs rarely metastasise. This is the first case of SCT with cutaneous metastasis described in the literature

    Increased urinary nitrite, a marker of nitric oxide, in active inflammatory bowel disease.

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    BACKGROUND: Nitric oxide (NO) production is increased in inflammatory bowel disease (IBD), and measurement of NO metabolites may be useful for monitoring disease activity. AIMS AND OBJECTIVES: To characterise urinary nitrite levels, a stable metabolite of NO, in IBD and to evaluate its potential as a marker of disease activity. METHODS: Twelve-hour urinary nitrites were measured by the microplate assay method in 46 patients with IBD (active; n = 32). Urinary samples from 16 healthy individuals served as controls. RESULTS: Increased levels of urinary nitrites were found in patients with active IBD compared with those with inactive IBD. Twenty-eight out of 32 patients (87.5%) with active IBD had detectable levels of nitrite in their urine as compared with 2/14 (14.3%) patients with inactive IBD. None of the 16 healthy controls had detectable urinary nitrite. Twelve-hour urinary nitrite in active compared with inactive IBD: 5 0.7 versus 0.1+/-0.04 micromol (P < 0.05). There was good correlation between urinary nitrite and some markers of disease activity in IBD such as C-reactive protein and microalbuminuria but not with erythrocyte sedimentation rate. Conclusions: Increased levels of nitrite were detected in urine of patients with active IBD, consistent with increased NO synthesis. This simple assay may be exploited as a potential marker of disease activity in IBD

    Blood testosterone threshold for androgen deficiency symptoms.

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    There are few systematic studies of the relationship between blood testosterone concentrations and the symptoms of overt androgen deficiency. Because most testosterone preparations are relatively short-term, the rapid changes in blood testosterone concentrations they cause make it difficult to define any testosterone threshold. By contrast, subdermal testosterone implants provide stable blood testosterone concentrations over days to weeks, while gradually declining to baseline over 5-7 months. Hence, this provides an opportunity to define a blood testosterone threshold for androgen deficiency symptoms by observing androgen-deficient men as their familiar androgen deficiency symptoms return as testosterone pellets slowly dissolve. Among 52 androgen-deficient men who underwent 260 implantations over 5 yr, at the time of return of androgen deficiency symptoms the blood total and free testosterone concentrations were highly reproducible within individuals (F ‫؍‬ 0.8, P ‫؍‬ 0.49 and F ‫؍‬ 1.4, 0.24, respectively) but varied markedly between men (F ‫؍‬ 167 and F ‫؍‬ 138, both P &lt; 0.001), indicating that each person had a consistent testosterone threshold for androgen deficiency symptoms that differed markedly between individuals. The most reported symptoms of androgen deficiency were lack of energy, lack of motivation, and reduced libido. The symptomatic threshold was significantly lower in men with secondary hypogonadism compared with men with primary or mixed hypogonadism (total, 9.7 ؎ 0.5 nmol/liter vs. T HE EFFECTS OF androgen deficiency and replacement on objective endpoints, notably bone (1, 2) and muscle (3-7), are well known and increasingly studied. Yet, whereas symptoms of androgen deficiency are discussed in textbooks and form the basis for practical clinical monitoring of androgen replacement therapy (8), there is a paucity of systematic studies of the symptoms of, and symptomatic threshold for, androgen deficiency. The subjective effects of androgen deficiency and replacement have generally been studied as objectively recorded measures of mood, behavior and cognitive responses (9 -11), but symptoms themselves are more difficult to study objectively. As a result, subjective effects of androgens have received most attention in the psychology literature, where empirical studies are, however, largely observational and restricted to eugonadal men limiting the salience of any inferences regarding relationships of blood testosterone concentrations to symptoms of overt androgen deficiency. A major limitation of interventional clinical research on androgen deficiency symptoms is that the available relatively short-term testosterone preparations produce swings in blood testosterone levels over days to weeks, which make it difficult or impossible to distinguish reliably symptom resolution and reappearance from pharmacological effects. The present study overcomes this limitation by using a long-acting depot testosterone preparation, which maintains stable blood testosterone concentrations over days to weeks but, as the biodegradable implants erode, allows them to decline slowly back to baseline over 5-7 months (12-15). Because the treated men return for blood testosterone measurement and reimplantation when their familiar androgen deficiency symptoms return, this allows a prospective evaluation of the relationships between individual androgen deficiency symptoms and the blood testosterone concentrations that accompany them. Subjects and Methods Patients We reviewed prospectively collected data from patients having regular androgen replacement therapy with a standard dose (four 200-mg pellets) of subdermal testosterone implants for androgen deficiency as described previously Procedures Implantation procedure. Testosterone pellet implantation procedures are booked throughout the week. At visits, men have a blood sample drawn JCEM is published monthly by The Endocrine Society (http://www. endo-society.org), the foremost professional society serving the endocrine community

    Ultrafast Raman laser mode-locked by nanotubes

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    We demonstrate passive mode-locking of a Raman fiber laser using a nanotube-based saturable absorber coupled to a net normal dispersion cavity. This generates highly chirped 500 ps pulses. These are then compressed down to 2 ps , with 1.4 kW peak power, making it a simple wavelength-versatile source for various applications
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