134,876 research outputs found
Application of the Fisher-Rao metric to ellipse detection
No full textThe parameter space for the ellipses in a two dimensional image is a five dimensional manifold, where each point of the manifold corresponds to an ellipse in the image. The parameter space becomes a Riemannian manifold under a Fisher-Rao metric, which is derived from a Gaussian model for the blurring of ellipses in the image. Two points in the parameter space are close together under the Fisher-Rao metric if the corresponding ellipses are close together in the image. The Fisher-Rao metric is accurately approximated by a simpler metric under the assumption that the blurring is small compared with the sizes of the ellipses under consideration. It is shown that the parameter space for the ellipses in the image has a finite volume under the approximation to the Fisher-Rao metric. As a consequence the parameter space can be replaced, for the purpose of ellipse detection, by a finite set of points sampled from it. An efficient algorithm for sampling the parameter space is described. The algorithm uses the fact that the approximating metric is flat, and therefore locally Euclidean, on each three dimensional family of ellipses with a fixed orientation and a fixed eccentricity. Once the sample points have been obtained, ellipses are detected in a given image by checking each sample point in turn to see if the corresponding ellipse is supported by the nearby image pixel values. The resulting algorithm for ellipse detection is implemented. A multiresolution version of the algorithm is also implemented. The experimental results suggest that ellipses can be reliably detected in a given low resolution image and that the number of false detections
can be reduced using the multiresolution algorithm
A Fisher-Rao metric for paracatadioptric images of lines
No full textIn a central paracatadioptric imaging system a perspective camera takes an image of a scene reflected in a paraboloidal mirror. A 360° field of view is obtained, but
the image is severely distorted. In particular, straight lines in the scene project to circles in the image. These distortions make it diffcult to detect projected lines using standard image processing algorithms. The distortions are removed using a Fisher-Rao metric which is defined on the space of projected lines in the paracatadioptric image. The space of projected lines is divided into subsets such that on each subset the Fisher-Rao metric is closely approximated by the Euclidean metric. Each subset is sampled at the vertices of a square grid and values are assigned to the sampled points using an adaptation of the trace transform. The result is a set of digital images to which standard image processing algorithms can be applied.
The effectiveness of this approach to line detection is illustrated using two algorithms, both of which are based on the Sobel edge operator. The task of line detection is reduced to the task of finding isolated peaks in a Sobel image. An experimental comparison is made between these two algorithms and third algorithm taken from the literature and
based on the Hough transform
Empirical likelihood inference for the Rao-Hartley-Cochran sampling design
No full textThe Hartley-Rao-Cochran sampling design is an unequal probability sampling design which can be used to select samples from finite populations. We propose to adjust the empirical likelihood approach for the Hartley-Rao-Cochran sampling design. The approach proposed intrinsically incorporates sampling weights, auxiliary information and allows for large sampling fractions. It can be used to construct confidence intervals. In a simulation study, we show that the coverage may be better for the empirical likelihood confidence interval than for standard confidence intervals based on variance estimates. The approach proposed is simple to implement and less computer intensive than bootstrap. The confidence interval proposed does not rely on re-sampling, linearization, variance estimation, design-effects or joint inclusion probabilities
Anneckia Subba Rao 1970
No full textAnneckia Subba Rao, 1970. Papua New Guinea, East New Britain, Raunsepna. Figs A7, B7, C7, D7, E7, F7 (all A. oophaga Subba Rao).Published as part of Huber, John T., Bolte, Klaus & Read, Jennifer D., 2023, The morphological diversity of Mymaridae (Hymenoptera): an atlas of scanning electron micrographs. Part 1. General overview and structure of the head, pp. 1-100 in Zootaxa 5273 (1) on page 26, DOI: 10.11646/zootaxa.5273.1.1, http://zenodo.org/record/789251
Squeaking in Total Hip Arthroplasty: a Scoping Review on a Biotribological Issue
No full textCeramic-on-ceramic bearings for total hip arthroplasty (THA) are considered to be the best choice to avoid problems such as osteolysis and wear, which are mainly caused by soft bearings. Recent concerns have been raised because of some clinical reports on the presence of audible noise (squeaking) in some ceramic-on-ceramic total hip replacements. The occurrence of squeaking in some patients is related to a complex of tribological and dynamical interactions in the prosthesis components. Such mechanisms include edge loading, stripe wear, impingement, synovial lubrication film ruptures, third body particles, ceramic fracture, and vibrational modes of the entire structure. The resonance of metallic parts can produce noise in the human audible frequencies range, hence the implant metallurgic composition, the design and the tribological behavior play a key role. The aim of this scoping review is to map and summarize the available scientific evidence on hip squeaking, highlighting the theoretical fundamentals on the genesis of the phenomenon with its causes and effects, the adopted numerical approaches together with in-situ experiments, results about squeaking analysis of total hip replacements listed in order of time so that it is easier follow the progress of science and the research future directions. Hence the scope is to provide a comprehensive but at the same time exhaustive document that could help researchers, students, etc. to study more deeply this field
Computing the Cramer-Rao bound of Markov random field parameters: Application to the Ising and the Potts models
No full textThis letter considers the problem of computing the Cramer–Rao bound for the parameters of a Markov random field. Computation of the exact bound is not feasible for most fields of interest because their likelihoods are intractable and have intractable derivatives. We show here how it is possible to formulate the computation of the bound as a statistical inference problem that can be solve approximately, but with arbitrarily high accuracy, by using a Monte Carlo method. The proposed methodology is successfully applied on the Ising and the Potts models
An inhalative immunotherapy in RAO-affected horses: dose-response study and comparison to beclomethasone inhalation
No full textDie Recurrent airway obstruction (RAO) ist eine chronische Erkrankung der unteren Atemwege bei Pferden mit multifaktorieller Genese. Da es sich um eine sehr weit verbreitete Erkrankung in der Pferde-Population handelt, besteht ein großes Interesse daran, neben den bisher gängigen Therapeutika, die vor allem die Symptome bekämpfen, neue Behandlungsoptionen zu finden.
Eine Therapieoption, die die Erkankung auf immunologischer Ebene modulieren kann, bietet die Inhalation von unmethylierten Cytosin-Phosphat-Guanin-Oligodeoxynukleotiden (CpG-ODN, kurz CPG). Das sind kurze DNA-Stränge, die aufgrund der Frequenz der Motive und dem Methylierungsgrad Ähnlichkeit mit der DNA von Bakterien bzw. Viren besitzen und somit vom Körper als fremd erkannt werden. Diese CpG könnten das Immunsystem weg von einer, bei Allergien dominierenden Th2-, hin zu einer spezifischen Th1-geprägten Immunantwort lenken. Um die Aufnahme der CpGs in die Zellen verbessern zu können und vor einem vorzeitigen Abbau der DNA durch Nukleasen zu schützen, werden als Trägersystem Gelatinenanopartikel (GNP) verwendet.
In der aktuellen doppelt-verblindeten Studie wurden RAO-Pferde, mittels geschichteter Zufallverteilung randomisert, in drei unterschiedliche Behandlungsgruppen unterteilt. Dabei erhielt eine Gruppe eine einfache CpG-Dosis (CpGsd) von 187,5μg CpG/Inhalation, die zweite Gruppe die doppelte Dosis (CpGdd) mit 375μg CpG/Inhalation und die dritte Gruppe zum Vergleich eine etablierte Therapie mit Beclometason, einem inhalativen Kortikosteroid. Alle Pferde erhielten insgesamt 10 Inhalationen.
Ziel der Studie war es den Behandlungserfolg durch die inhalative CpG-Therapie unter Beweis zu stellen sowie den Dosis-Wirkungs-Effekt und die Leistungsfähigkeit der CpG-Therapie im direkten Vergleich mit einer bewährten antiinflammatorischen Inhalationstherapie mit Beclometason zu evaluieren.
In der verblindeten klinischen Feldstudie wurden insgesamt 29 RAO-Pferde in ihren Heimatställen behandelt. Bewertet wurde der Therapieeinfluss auf die klinischen Parameter Ruheatemfrequenz, Atemtyp, Nasenausfluss, Auskultation, Sauerstoffpartialdruck, Arterioalveoläre Sauerstoffdifferenz, Interpleuraldruck, Mukusmenge- bzw. –viskosität in der Trachea, Neutrophile in der BAL (Bronchoalveoläre Lavage), klinisches Scoring und HOARSI (Horse Owner Assessed Respiratory Signs Index). Dafür wurden alle Pferde drei Mal untersucht. Die erste Untersuchung erfolgte vor dem Start der Behandlung (US1), die zweite am Tage nach der letzten Behandlung (US2). Die dritte Untersuchung (US3) erfolgte acht Wochen nach der letzten Inhalation, um den Langzeiteffekt beurteilen zu können.
Direkt nach der Behandlung bei US2 konnten sowohl die CpGsd Gruppe, die bei 90% der klinischen Parameter eine signifikante Verbesserung erzielen konnte als auch die CpGdd Gruppe, die bei 81% der gemessenen Werte signifikante Verbesserungen bewirken konnte, einen Vorteil gegenüber der Kortisontherapie (72%) aufweisen. Noch eindeutiger fielen die Ergebnisse, die bezüglich der Langzeitevaluierung erhoben wurden, aus. Hier ist mit der positiven signifikanten Beeinflussung von 100% der klinischen Parameter bei der CpGsd und 67% bei der CpGdd, im Vergleich zu 54% bei der Kortisontherapie, ein klarer Vorteil in der therapeutischen Wirksamkeit aufseiten der CpG-Behandlung zu erkennen. Als wichtiger Indikator für die antiinflammatorische Wirkung ist die langfristige signifikante Reduktion der Neutrophilen in der BAL durch die beiden CpG-Gruppen hervorzuheben, wohingegen bei der Beclometason-Inhalation hier keine signifikante Reduktion festgestellt werden konnte. Von besonderer Relevanz ist außerdem die Einschätzung der Pferdebesitzer bezüglich der klinischen Symptomatik mittels standadisiertem HOARSI-Fragebogen. Hier bewerteten die Besitzer beider CpG-Dosis-Gruppen den Zustand ihrer Pferde, 8 Wochen nach der Behandlung als signifikant besser als vor der Therapie, während die Einstufung der Verbesserung nach der Beclometason-Therapie nicht signifikant ausfiel. Da sich das gesamte klinische Bild für die Besitzer merklich verbesserte, konnte somit eines der wichtigsten Ziele der Behandlung erreicht werden.
Die Erhöhung der CpG-Dosis auf die doppelte Menge konnte, auf die Gesamtzahl der klinischen Parameter gesehen, keine besseren Ergebnisse bewirken, als die ursprüngliche einfache Dosis. Die CpGsd konnte sogar bei einem breiteren Spektrum an klinischen Parametern eine signifikante Verbesserung erzielen als die CpGdd. Diese Ergebnisse sprechen daher also dafür, dass die einfache Dosierung (187,5μg CpG/Inhalation) zur Behandlung der RAO ausreicht. Hinsichtlich der Therapieverträglichkeit konnten keinerlei negative Auswirkungen auf die Patienten beobachtet werden.
Auf immunologischer Ebene konnte nach der Behandlung mit CpGs signifikante Reduktionen des Th2-Zytokins IL-4 sowie des Th17-Zytokins IL-17 festgestellt werden. Beide Zytokine spielen eine Rolle in der Rekruitierung von neutrophilen Granulozyten. Auch wenn die Ergebnisse der mRNA-Auswertungen statistisch nicht signifikant waren, deutete auch hier eine Vielzahl der Ergebnisse auf eine tendenziell antiinflammatorische Wirkung durch die CpG-Therapie hin. Hier konnte u.a. die Tendenz einer Absenkung der IL-8- sowie der GATA-3-mRNA-Expression verzeichnet werden, was sowohl auf einen antiinflammatorischen, als auch einen immunmodulatorischen Effekt, weg von einer Th2-dominierten Immunantwort, hindeutet.
In zukünftigen Studien wäre eine Untersuchung an einer größeren Patientengruppe wünschenswert, um ein noch besseres Verständnis der immunonologischen Verhältnisse in den unterschiedlichen Erkrankungsphasen (Remission oder Exazerbation) bei RAO erreichen zu können und damit die Aussagekraft hinsichtlich der therapeutischen Veränderungen noch weiter stärken zu können. Außerdem könnte eine größere Patientenzahl individuelle Schwankungen, v.a. der Zytokinergebnisse besser ausgleichen. Ein direkter Nachweis regulatorischer T-Zellen zur Evaluation des Therapieeinflusses auf die Tregs wäre in weiterführenden Studien wünschenswert. Da den Tregs in der Pathogenese des humanen Asthmas bereits eine wichtige Rolle zugesprochen wird, sollte deren Bedeutung in der RAO-Erkrankung genauer auf den Grund gegangen werden.
Da humanes Asthma und die equine RAO hinsichtlich zahlreicher Aspekte, u.a. in der Pathogenese und dem Ansprechen auf Therapie, Parallelen aufweisen, wäre es wünschenswert, dass die Möglichkeit der inhalativen Therapie mit CpGs in zukünftigen Studien über die Behandlung von RAO hinaus, auch bei Asthma-Patienten in großangelegten Studien weiterführend untersucht wird.Recurrent airway obstruction (RAO) is a chronic disease of the lower respiratory tract in horses with multifactorial aetiology. As RAO is a widespread disease in the horse population, there is a great interest in finding new treatment options in addition to the established therapies, which mainly aim at controlling the symptoms of the disease instead of treating the causes.
A therapy option that can modulate immunodeficiency is the inhalation of unmethylated cytosine-phosphate-guanine oligodeoxynucleotides (CpG-ODN or CPG for short). These are short DNA strands which resemble the DNA of bacteria or viruses due to the frequency of the motifs and the degree of methylation and are thus recognized as foreign by the body. These CpG could redirect the immune response from an allergic dominant Th2- to a specific Th1-imprinted immune response. In order to improve the uptake of the CpGs into the cells and to protect them from premature degradation of the DNA by nucleases, gelatin nanoparticles (GNP) are used as the carrier system.
In the current double-blinded study, RAO horses were divided into three different treatment groups by a stratified random distribution. The first group was treated with a simple CpG dose (CpGsd) of 187.5 μg CpG/inhalation, the second group with the double dose (CpGdd) of 375 μg CpG/inhalation, and the third group with an established beclometason therapy which is an inhalative corticosteroid. All horses received a total of 10 inhalations.
The aim of the study was to demonstrate the efficacy of CpG therapy by inhalation, to evaluate the dose-response effect and the efficacy of CpG therapy in direct comparison with a proven anti-inflammatory inhalative therapy with beclometasone.
In this blinded field study, a total of 29 RAO horses were treated in their home stables. The therapeutic effect was measured using the clinical parameters of respiratory rate, breathing type, nasal discharge, auscultation, arterial oxygen pressure, arterioalveolar oxygen difference, interpleural pressure, tracheal mucus, neutrophils in BAL (bronchoalveolar lavage), clinical scoring and HOARSI (Horse Owner Assessed Respiratory Signs Index). For this, all horses were examined three times. The first examination was performed before the start of the treatment (US1), the second on the day after the last treatment (US2). The third examination (US3) took place eight weeks after the last inhalation in order to assess the long-term effect.
Directly after treatment (US2), the CpGsd group, which achieved a significant improvement in 90% of the clinical parameters, as well as the CpGdd group, which led to significant improvements in 81% of the measured values, had an advantage over cortisone therapy which only showed significant improvement in 72% of the parameters. The results obtained regarding the long-term evaluation are even clearer. Here, treatment led to a significant positive change of the clinical parameters in 100% and 65% of the CpGsd and the CpGdd group, respectively which contrasted to positive changes in only 54% of the parameters in the cortisone group. Accordingly, treatment with CpG shows a clear advantage over therapy with cortisone.As an important indicator for the anti-inflammatory effect, the long-term reduction of the neutrophils in the BAL by the two CpG groups was significant, whilst the beclometason inhalation did not show a significant long-term reduction of neutrophils. Of particular relevance is also the assessment of the horse owners regarding the clinical symptoms by a standardized HOARSI questionnaire. Here, the owners of both CpG dose groups rated their horses' condition, 8 weeks after treatment, as significantly better than before treatment, while improvement after beclomethasone therapy was not significant. As the overall clinical picture improved significantly for the owners, one of the main goals of the treatment was achieved.
Based on the total numbers of clinical parameters affected in a positive manner, increasing the CpG dose to twice the amount did not produce better results than the original single dose. The CpGsd treatment was able to achieve a significant improvement in an even wider range of clinical parameters than the CpGdd. These results therefore suggest that the simple dosage (187.5 μg CpG / inhalation) is sufficient to treat RAO. No adverse effects on the patients could be observed regarding the therapy tolerability.
On the immunological level, significant reductions of Th2 cytokines IL-4 and IL-17 were found after treatment with CpGs. Although the results of the mRNA analyzes were not statistically significant, a large number of the results indicated a tendency towards anti-inflammatory effects during CpG therapy. Here, the tendency to lower IL-8 as well as GATA-3 mRNA expressions was recorded, indicating both an anti-inflammatory and an immunomodulatory effect away from a Th2-dominated immune response.
In future studies, an examination of a larger group of patients would be desirable in order to achieve an even better understanding of the immunological conditions in the different phases of RAO (remission or exacerbation) and thus to further strengthen the significance of the therapeutic changes. Moreover, a larger number of patients could reduce individual fluctuations on the total cytokine results. A direct detection of regulatory T cells for the evaluation of the therapeutic effect on the Tregs would be desirable in further studies. Since Tregs already play an important role in the pathogenesis of human asthma, its importance in the RAO disease should be more precisely evaluated.
As human asthma and equine RAO are closely related regarding pathogenesis and response to therapy, it would be desirable that the possibility of inhaled therapy with CpGs would be further investigated in future large-scale studies on the treatment of RAO horses as well as asthma patients
Taxonomic Relationship between Tylototriton daweishanensis Zhao, Rao, Liu, Li and Yuan, 2012 and T. yangi Hou, Li and Lu, 2012 (Amphibia: Urodela: Salamandridae)
No full textWe assessed taxonomic relationship of Tylototriton daweishanensis Zhao, Rao, Liu, Li and Yuan, 2012 and T. yangi Hou, Li and Lu, 2012 using mitochondrial DNA sequence data and found them to be as closely related as to be regarded as conspecific. This result, together with available morphological information, strongly indicates that T. daweishanensis is a junior synonym of T. Yangi
Tetranchyroderma paralittorale Rao 1991
No full textTetranchyroderma paralittorale Rao, 1991 Records from India. LAKSHADWEEP: Androth—Rao (1991); GENERAL RECORD: Naidu & Rao (2004). Habitat. Marine, intertidal; coarse and clean coralline sand, 10 cm below surface, near half-tide level. Distribution. India (Arabian Sea). Remarks. Hummon & Todaro (2010) changed the species name ending from T. paralittoralis to T. paralittorale according to the genus gender.Published as part of Chatterjee, Tapas, Priyalakshmi, Geetha & Todaro, M. Antonio, 2019, An annotated checklist of the macrodasyidan Gastrotricha from India, pp. 495-510 in Zootaxa 4545 (4) on page 504, DOI: 10.11646/zootaxa.4545.4.3, http://zenodo.org/record/261830
Tetranchyroderma tentaculatum Rao 1993
No full textTetranchyroderma tentaculatum Rao, 1993 Records from India. ANDAMAN & NICOBAR ISLANDS: West Bay, Little Andaman—Rao (1993); GENERAL RECORD: Naidu & Rao (2004). Habitat. Marine, intertidal; medium sand with a little detritus, 10 cm below surface, near half-tide level. Distribution. India (Bay of Bengal). Remarks. Hummon & Todaro (2010) changed the species name ending from T. tentaculata to T. tentaculatum according to the genus gender.Published as part of Chatterjee, Tapas, Priyalakshmi, Geetha & Todaro, M. Antonio, 2019, An annotated checklist of the macrodasyidan Gastrotricha from India, pp. 495-510 in Zootaxa 4545 (4) on page 505, DOI: 10.11646/zootaxa.4545.4.3, http://zenodo.org/record/261830
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