253,616 research outputs found
Genetik der rezidivierenden Atemwegsobstruktion (RAO)
No full textRecurrent airway obstruction (RAO) is a multifactorial and polygenic disease. Affected horses are typically 7 years of age or older and show exercise intolerance, increased breathing effort, coughing, airway neutrophilia, mucus accumulation and hyperreactivity as well as cholinergic bronchospasm. The environmental factors responsible are predominantly allergens and irritants in haydust, but the immunological mechanisms underlying RAO are still unclear. Several studies have demonstrated a familiar predisposition for RAO and it is now proven that the disease has a genetic basis. In offspring, the risk of developing RAO is 3-fold increased when one parent is affected and increases to almost 5-fold when both parents have RAO. Segregation analysis in two high-prevalence families demonstrated a high heritability and a complex inheritance with several major genes. A whole genomescan showed chromosome-wide significant linkage of seven chromosomal regions with RAO. Of the microsatellites, which were located near atopy candidate genes, those in a region of chromosome 13 harboring the IL4R gene were strongly associated with the RAO phenotype in the offspring of one RAO-affected stallion. Furthermore, IgE-levels are influenced by hereditary factors in the horse, and we have evidence that RAO-affected offspring of the same stallion have increased levels of specific IgE against moldspore allergens. The identification of genetic markers and ultimately of the responsible genes will not only allow for an improved prophylaxis, i.e. early identification of susceptible individuals and avoidance of high-risk matings, but also improve our ability to find new therapeutic targets and to optimize existing treatments.Die rezidivierende Atemwegsobstruktion (RAO) ist eine multifaktoriell bedingte Erkrankung. Betroffene Pferde sind meist älter als 7-jährig und zeigen Leistungseinbußen, eine verstärkte Atmung, Husten, Neutrophilie und Schleimansammlungen in den Atemwegen, Atemwegshyperreaktivität und cholinergen Bronchospasmus. Verantwortlich gemacht werden vor allem Allergene und Irritantien im Heustaub, aber die immunologischen Ursachen und Mechanismen der RAO sind nicht eindeutig geklärt. Mehrere Studien haben gezeigt, dass die RAO familiär gehäuft auftritt, und es ist nun gesichert, dass die Krankheit auch durch genetische Faktoren beeinflusst wird. Das Risiko, RAO zu entwickeln, ist bei Nachkommen eines betroffenen Elterntiers 3-fach erhöht und steigt bei Pferden mit zwei betroffenen Elternteilen weiter auf fast das 5-fache an. Eine Erbgangsanalyse in zwei Familien zeigte eine hohe Heritabilität (h2) und einen komplexen Erbgang, an dem mehrere Hauptgene beteiligt sind. In einem Genomscan konnten wir bereits 7 chromosomale Regionen identifizieren, die chromosomenweit mit RAO gekoppelt sind. Mikrosatelliten in der Nähe des IL4R Gens auf Chromosom 13, einem bekannten Kandidatengen für Atopie, waren mit RAOSymptomen bei den Nachkommen von einem betroffenen Hengst gekoppelt. Weiter sind IgE-Titer auch beim Pferd durch erbliche Faktoren beeinflusst, und wir haben Hinweise darauf, dass die Nachkommen desselben betroffenen Hengstes erhöhte IgE-Titer gegen ein bestimmtes Schimmelpilz-Allergen haben. Die Identifizierung genetischer Marker und schließlich der für RAO verantwortlichen Gene wird nicht nur die Prophylaxe der RAO verbessern, indem prädisponierte Individuen frühzeitig erkannt und risikoreiche Paarungen vermieden werden können, sondern durch das bessere Verständnis der Pathogene auch die Identifikation neuer therapeutischer Ansätze oder die Optimierung vorhandener Therapien erlauben
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
Cramér-Rao Bound for Hybrid GNSS-Terrestrial Cooperative Positioning
No full textIn this contribution we derive an expression of the Cramer-Rao bound for hybrid cooperative positioning, where GNSS information is combined with terrestrial range measurements through exchange of peer-to-peer messages. These results provide a theoretical characterization of achievable performance of hybrid positioning schemes, as well as allow to identify critical network configurations and devise optimized node placement strategies
Cyrtodactylus khasiensis Yang and Rao 2008
No full textCyrtodactylus khasiensis Yang and Rao 2008: 176 Holotype. KIZ L2019044, adult male, collected by Shuo Liu on 3 September 2018 from Tongbiguan Township, Yingjiang County, Dehong Autonomous Prefecture, Yunnan Province, China (24° 36′ 51″ N, 97° 35′ 2″ E, at an elevation of 1170 m asl). Paratype. KIZ 2003170, adult male, collected by Datong Yang on 14 May 2003 from Lvliang Village (elevation of 1200 m asl), Longchuan County, Dehong Autonomous Prefecture, Yunnan Province, China.Published as part of Liu, Shuo & Rao, Dingqi, 2021, A new species of Cyrtodactylus Gray, 1827 (Squamata: Gekkonidae) from Western Yunnan, China, pp. 713-731 in Journal of Natural History 55 (11 - 12) on pages 717-718, DOI: 10.1080/00222933.2021.1921871, http://zenodo.org/record/546375
Nirvana shillongenisis Rao
No full textNirvana shillongenisis Rao (Rao 1989: Fig. 19) Nirvana shillongenis Rao: 62 (not examined) Female: Unknown.Published as part of Meshram, Naresh M. & Rai, Stuti, 2017, A new species of genus Nirvana (Hemiptera: Cicadellidae: Evacanthinae) with note on female genitalia from India, pp. 264-272 in Zootaxa 4303 (2) on page 271, DOI: 10.11646/zootaxa.4303.2.6, http://zenodo.org/record/84094
Species Metapenaeus monoceros
No full textMetapenaeus monoceros, (Fabricius 1798)
the ‘brown shrimp’ is a commercially important
prawn in the backwaters and estuaries, and up to
about 100 m depth in the sea. Many have worked
on different aspects of this species as it contributes
to the fishery in many countries bordering the
Arabian Sea. Notable among them are George (1959,
1970, 1974), George et al. (1963, 1988), Mohamed
and Rao (1971), Rao (1973a), Subrahmanyam (1965,
1967a, 1973), Kuttyamma (1973), Rao and
Krishnamoorthi (1990), Nalini (1976), Lalithadevi
(1988), Nandakumar and Srinath (1999) and
Dineshbabu (2006). Rao (1985, 1988a, 1988b, 1988c,
1988d, 1989, 1993c, 1994) studied the fishery and
biology of the species along the Kakinada coast
while Nandakumar (1998, 2000, 2001a, 2001b, 2004)
studied the biology and fishery of the species at
Cochin. Sukumaran et al. (1993) gave a
comprehensive account on the fishery, biology and
population dynamics of the resource on an all-India
basis
Pseudostomella indica Rao 1970
No full textPseudostomella indica Rao, 1970 Records from India. ANDHRA PRADESH: Palm beach, Visakhapatnam (Waltair)—Rao (1970); ODISHA: Gopalpur—Rao (1989); LAKSHADWEEP: Agatti—Rao (1991); WEST BENGAL: South 24 Parganas—Sanyal et al. (2012); GENERAL RECORD: Naidu & Rao (2004). Habitat. Marine, intertidal; medium sand, 10 cm below surface near mid-water level. Distribution. India (Bay of Bengal, Arabian Sea). Remarks. Endemic to India.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 502, DOI: 10.11646/zootaxa.4545.4.3, http://zenodo.org/record/261830
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
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