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Robust Adaptive Intra Refresh for Multiview Video
Transmission error propagation in wireless multimedia communication systems has become a recurring
problem. This persistent problem has led to grave consequences on the visual quality of the decoded video.
It is against this backdrop that, we present an adaptive intra refresh (AIR) error-resilient coding tool to
mitigate the effect of transmission error propagation in 3D video communications. This work utilizes
periodic insertion of intra macroblocks in badly error-infected frames temporally as well as related frames
in the multi view video scheme. Our objective is to maximize the transmission efficiency while ensuring the
transmission robustness of the coded bitstream. The selection of periodic macroblocks is based on areas
with high motion above a pre-set threshold. The coding modes of the macroblocks are based on the
distortion expectation due to transmission errors. Extensive simulation results show significant
improvement in both objective and subjective video quality at different intra refresh rates
The influence of μ-opioid and noradrenaline reuptake inhibition in the modulation of pain responsive neurones in the central amygdala by tapentadol in rats with neuropathy
Treatments for neuropathic pain are either not fully effective or have problematic side effects. Combinations of drugs are often used. Tapentadol is a newer molecule that produces analgesia in various pain models through two inhibitory mechanisms, namely central μ-opioid receptor (MOR) agonism and noradrenaline reuptake inhibition. These two components interact synergistically, resulting in levels of analgesia similar to opioid analgesics such as oxycodone and morphine, but with more tolerable side effects. The right central nucleus of the amygdala (CeA) is critical for the lateral spinal ascending pain pathway, regulates descending pain pathways and is key in the emotional-affective components of pain. Few studies have investigated the pharmacology of limbic brain areas in pain models. Here we determined the actions of systemic tapentadol on right CeA neurones of animals with neuropathy and which component of tapentadol contributes to its effect. Neuronal responses to multimodal peripheral stimulation of animals with spinal nerve ligation or sham surgery were recorded before and after two doses of tapentadol. After the higher dose of tapentadol either naloxone or yohimbine were administered. Systemic tapentadol resulted in dose-dependent decrease in right CeA neuronal activity only in neuropathy. Both naloxone and yohimbine reversed this effect to an extent that was modality selective. The interactions of the components of tapentadol are not limited to the synergy between the MOR and α2-adrenoceptors seen at spinal levels, but are seen at this supraspinal site where suppression of responses may relate to the ability of the drug to alter affective components of pain
Massive Hermitian Gravity
Einstein-Strauss Hermitian gravity was recently formulated as a gauge theory
where the tangent group is taken to be the pseudo-unitary group instead of the
orthogonal group. A Higgs mechanism for massive gravity was also formulated. We
generalize this construction to obtain massive Hermitian gravity with the use
of a complex Higgs multiplet. We show that both the graviton and antisymmetric
tensor acquire the same mass. At the linearized level, the theory is ghost free
around Minkowski background and describes a massive graviton with five degrees
of freedom and an antisymmetric field with three degrees of of freedom. We
determine the strong coupling scales for these degrees of freedom and argue
that the potential nonlinear ghosts, if they exist, have to decouple from the
gravitational degrees of freedom in strong coupling regime.Comment: 10 page
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Continuous growth of proximal tubular kidney epithelial cells in hormone-supplemented serum-free medium.
An epithelial cell line from pig kidney (LLC-PK1) with properties of proximal tubular cells can be maintained indefinitely in hormone-supplemented serum-free medium. Continuous growth requires the presence of seven factors: transferrin, insulin, selenium, hydrocortisone, triiodothyronine, vasopressin, and cholesterol. The hormone-defined medium (a) supports growth of LLC-PK1 cells at a rate of approaching that observed in serum-supplemented medium; (b) allows vectorial transepithelial salt and fluid transport as measured by hemicyst formation; and (c) influences cell morphology. The vasopressin dependency for growth and morphology can be partially replaced by isobutylmethylxanthine or dibutyryl cyclic AMP. The medium has been used to isolate rabbit proximal tubular kidney epithelial cells free of fibroblasts
Double point contact in Quantum Hall Line Junctions
We show that multiple point contacts on a barrier separating two laterally
coupled quantum Hall fluids induce Aharonov-Bohm (AB) oscillations in the
tunneling conductance. These quantum coherence effects provide new evidence for
the Luttinger liquid behavior of the edge states of quantum Hall fluids. For a
two point contact, we identify coherent and incoherent regimes determined by
the relative magnitude of their separation and the temperature. We analyze both
regimes in the strong and weak tunneling amplitude limits as well as their
temperature dependence. We find that the tunneling conductance should exhibit
AB oscillations in the coherent regime, both at strong and weak tunneling
amplitude with the same period but with different functional form.Comment: 4 pages, 3 figures; new version, edited text, 2 new references;
figure 2 has been edited; new paragraph in page 1 and minor typos have been
correcte
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Is endoanal, introital or transperineal ultrasound diagnosis of sphincter defects more strongly associated with anal incontinence?
INTRODUCTION AND HYPOTHESIS: Our aim was to explore the association between anal incontinence (AI) and persistent anal sphincter defects diagnosed with 3D endoanal (EAUS), introital (IUS) and transperineal ultrasound (TPUS) in women after obstetric anal sphincter injury (OASI) and study the association between sphincter defects and anal pressure. METHODS: We carried out a cross-sectional study of 250 women with OASI recruited during the period 2013-2015. They were examined 6-12 weeks postpartum or in a subsequent pregnancy with 3D EAUS, IUS and TPUS and measurement of anal pressure. Prevalence of urgency/solid/liquid AI or flatal AI and anal pressure were compared in women with a defect and those with an intact sphincter (diagnosed off-line) using Chi-squared and Mann-Whitney U test. RESULTS: At a mean of 23.6 (SD 30.1) months after OASI, more women with defect than those with intact sphincters on EAUS had AI; urgency/solid/liquid AI vs external defect: 36% vs 13% and flatal AI vs internal defect: 27% vs 13%, p < 0.05. On TPUS, more women with defect sphincters had flatal AI: 32% vs 13%, p = 0.03. No difference was found on IUS. Difference between defect and intact sphincters on EAUS, IUS and TPUS respectively was found for mean [SD] maximum anal resting pressure (48 [13] vs 55 [14] mmHg; 48 [12] vs 56 [13] mmHg; 50 [13] vs 54 [14] mmHg) and squeeze incremental pressure (33 [17] vs 49 [28] mmHg; 37 [23] vs 50 [28] mmHg; 36 [18] vs 50 [30] mmHg; p < 0.01). CONCLUSIONS: Endoanal ultrasound had the strongest association with AI symptoms 2 years after OASI. Sphincter defects detected using all ultrasound methods were associated with lower anal pressure
Massive Gravity Simplified: A Quadratic Action
We present a simplified formulation of massive gravity where the Higgs fields
have quadratic kinetic term. This new formulation allows us to prove in a very
explicit way that all massive gravity theories considered so far inevitably
have Boulware-Deser ghost in non-trivial fluctuations of background metric.Comment: 8 pages, paragraph added proving that Bianchi identity does not imply
vanishing of linearized curvatur
Coopetition of software firms in Open source software ecosystems
Software firms participate in an ecosystem as a part of their innovation
strategy to extend value creation beyond the firms boundary. Participation in
an open and independent environment also implies the competition among firms
with similar business models and targeted markets. Hence, firms need to
consider potential opportunities and challenges upfront. This study explores
how software firms interact with others in OSS ecosystems from a coopetition
perspective. We performed a quantitative and qualitative analysis of three OSS
projects. Finding shows that software firms emphasize the co-creation of common
value and partly react to the potential competitiveness on OSS ecosystems. Six
themes about coopetition were identified, including spanning gatekeepers,
securing communication, open-core sourcing and filtering shared code. Our work
contributes to software engineering research with a rich description of
coopetition in OSS ecosystems. Moreover, we also come up with several
implications for software firms in pursing a harmony participation in OSS
ecosystems.Comment: This is the author's version of the work. Copyright owner's version
can be accessed at
https://link.springer.com/chapter/10.1007/978-3-319-69191-6_10, Coopetition
of software firms in Open source software ecosystems, 8th ICSOB 2017, Essen,
Germany (2017
Lymphoma and hypercalcemia in a pediatric orthotopic liver transplant patient
We present a case report of a pediatric orthotopic liver transplant recipient who developed lymphoma with hypercalcemia on cyclosporine and prednisone immunosuppression. This is the first reported posttransplant lymphoproliferative disorder complicated by hypercalcemia, with a finding of an elevated 1,25 dihydroxyl vitamin D state, suggesting that it has a role in the pathophysiology of this B cell lymphoma hypercalcemia. The clinical course and management of this disorder with a 31-month follow-up are described. © 1989 by Williams & Wilkins
Deep Learning using K-space Based Data Augmentation for Automated Cardiac MR Motion Artefact Detection
Quality assessment of medical images is essential for complete automation of
image processing pipelines. For large population studies such as the UK
Biobank, artefacts such as those caused by heart motion are problematic and
manual identification is tedious and time-consuming. Therefore, there is an
urgent need for automatic image quality assessment techniques. In this paper,
we propose a method to automatically detect the presence of motion-related
artefacts in cardiac magnetic resonance (CMR) images. As this is a highly
imbalanced classification problem (due to the high number of good quality
images compared to the low number of images with motion artefacts), we propose
a novel k-space based training data augmentation approach in order to address
this problem. Our method is based on 3D spatio-temporal Convolutional Neural
Networks, and is able to detect 2D+time short axis images with motion artefacts
in less than 1ms. We test our algorithm on a subset of the UK Biobank dataset
consisting of 3465 CMR images and achieve not only high accuracy in detection
of motion artefacts, but also high precision and recall. We compare our
approach to a range of state-of-the-art quality assessment methods.Comment: Accepted for MICCAI2018 Conferenc
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