438 research outputs found
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The role of optometry in the delivery of eye health care in the European Union
The role of optometry in the delivery of eye healthcare in the UK is well recognised by the state and the British people. Optometry in Britain works very closely with medicine and is steadily moving forward as a profession complimentary to ophthalmology. However, with the exception of Ireland, the role of optometry in the rest of the European Union is restricted by national laws, decrees or acts like Actus Medicus to those professional activities which are normally carried out by dispensing opticians in the UK. From a British perspective there are no equivalent working optometrists in the EU except in Ireland. British optometrists provide an increasing amount of primary eye healthcare working closely with hospital based ophthalmologists who provide secondary care. In the rest of the European Union primary eye care is generally provided by practising ophthalmologists who refer patients to hospitals or university clinics for secondary care. With the growing elderly population and changing demography, the UK will remain short of human resources for the management of sight threatening conditions. It is not realistic to expect 750 British ophthalmologists to be responsible for secondary eye care for the entire population of the UK British standards in eye healthcare must be maintained and optometry in the EU must be reformed effectively and improve to British standards before freedom of movement is implemented under any EU legislation especially under the new directive which would allow healthcare professionals to work in the EU for 16 weeks without registration from the year 2005. British optometrists with appropriate additional training could be given the responsibility for the specific task of ophthalmic intervention to avoid blindness and visual impairment and this would provide a pragmatic solution to a human resources problem in the eye care field in the UK. Hopefully, such a model would then be adopted by the future optometrists trained throughout the European Union
Linkage QTL Mapping and Genome-Wide Association Study on Resistance in Chickpea to Pythium ultimum
The soilborne oomycete plant pathogen Pythium ultimum causes seed rot and pre-emergence damping-off of chickpea (Cicer arietinum L.). The pathogen has been controlled for several decades using the fungicide metalaxyl as seed treatment but has re-emerged as a severe problem with the detection of metalaxyl-resistant isolates of the pathogen from infested fields in the United States Pacific Northwest. The objective of this study was to identify genetic markers and candidate genes associated with resistance to P. ultimum in an interspecific recombinant inbred line population (CRIL-7) derived from a cross between C. reticulatum (PI 599072) x C. arietinum (FLIP 84-92C) and conduct genome-wide association studies (GWAS) for disease resistance using a chickpea diversity panel consisting of 184 accessions. CRIL-7 was examined using 1029 SNP markers spanning eight linkage groups. A major QTL, “qpsd4-1,” was detected on LG 4 that explained 41.8% of phenotypic variance, and a minor QTL, “qpsd8-1,” was detected on LG8 that explained 4.5% of phenotypic variance. Seven candidate genes were also detected using composite interval mapping including several genes previously associated with disease resistance in other crop species. A total of 302,902 single nucleotide polymorphic (SNP) markers were used to determine population structure and kinship of the diversity panel. Marker–trait associations were established by employing different combinations of principal components (PC) and kinships (K) in the FarmCPU model. Genome-wide association studies detected 11 significant SNPs and seven candidate genes associated with disease resistance. SNP Ca4_1765418, detected by GWAS on chromosome 4, was located within QTL qpsd4-1 that was revealed in the interspecific CRIL-7 population. The present study provides tools to enable MAS for resistance to P. ultimum and identified genomic domains and candidate genes involved in the resistance of chickpea to soilborne diseases
CicArMiSatDB: the chickpea microsatellite database
Background
Chickpea (Cicer arietinum) is a widely grown legume crop in tropical, sub-tropical and temperate regions. Molecular breeding approaches seem to be essential for enhancing crop productivity in chickpea. Until recently, limited numbers of molecular markers were available in the case of chickpea for use in molecular breeding. However, the recent advances in genomics facilitated the development of large scale markers especially SSRs (simple sequence repeats), the markers of choice in any breeding program. Availability of genome sequence very recently opens new avenues for accelerating molecular breeding approaches for chickpea improvement.
Description
In order to assist genetic studies and breeding applications, we have developed a user friendly relational database named the Chickpea Microsatellite Database (CicArMiSatDB http://cicarmisatdb.icrisat.org). This database provides detailed information on SSRs along with their features in the genome. SSRs have been classified and made accessible through an easy-to-use web interface.
Conclusions
This database is expected to help chickpea community in particular and legume community in general, to select SSRs of particular type or from a specific region in the genome to advance both basic genomics research as well as applied aspects of crop improvement
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Repeatability and comparison of clinical techniques for anterior chamber angle assessment
Purpose
To assess the repeatability of gonioscopy, van Herick method and anterior segment Optical Coherence Tomography (AS-OCT) and determine the agreement between these techniques within a community optometry setting.
Methods
Gonioscopy, van Herick method and AS-OCT imaging were performed by an optometrist on two occasions, 1 month apart, on 80 subjects aged over 40 years recruited from community optometry practices. Anterior segment images were captured with a spectral domain OCT (Topcon 3D OCT-2000; wavelength 840 nm) set to the Anterior Segment (AS) mode. Eyes were graded as open or occludable for each method. AS-OCT images from both visits were graded by a second optometrist masked to the gonioscopy and van Herick method results, and the visit on which the images were acquired. Cohen's kappa (Îş) was used to describe the intra-observer repeatability. Likelihood ratios, sensitivity and specificity of van Herick method and AS-OCT were calculated, using gonioscopy as the reference standard.
Results
Measurements were obtained from 80 eyes of 80 subjects. In four cases, AS-OCT images were un-gradable due to difficulty in locating the scleral spur. The repeatability of gonioscopy was fair Îş = 0.29, while that of the van Herick method (Îş = 0.54) and AS-OCT (Îş = 0.47) were somewhat better. The van Herick method showed good sensitivity (visit 1: 75%, visit 2: 69%) and high specificity (visit 1: 88%, visit 2: 96%). The sensitivity of AS-OCT was fair (visit 1: 46%, visit 2: 25%), but specificity was high (visit 1: 87%. visit 2: 89%).
Conclusion
Intra-observer repeatability was better for van Herick method and for AS-OCT than for gonioscopy, despite the latter being considered the gold standard method. The van Herick method appeared to be more sensitive than AS-OCT when identifying eyes at risk of angle closure. A standalone anterior segment OCT with a longer wavelength laser could afford better visualisation of the angle, and might therefore be expected to enable the examiner to make more precise classifications. These instruments are not widely used by optometrists in clinical practice in the UK at present
Molecular markers and genomic resources for disease resistance in peanut-A review
Recent polyploidation of peanut genome and geographical isolation has rendered peanut to be a highly monomorphic species. Due to its narrow genetic base, cultivated peanut has been susceptible to various diseases, causing economic loss to farmers. Availability of only a few disease resistance sources in cultivated peanut has resulted in limited success using the conventional breeding practices. Also, scarcity of markers has been the major limiting factor to precisely identify the disease resistance genomic regions. Recent identification of large number of molecular markers using advanced genomic resources and high throughput sequencing technologies has and will continue to assist in improvement of peanut diversity and breeding. This review gives an update on recent discovery of molecular markers associated with major diseases and the available genomic resources in peanut
Identification of a non-redundant set of 202 in silico SSR markers and applicability of a select set in chickpea (Cicer arietinum L.)
The paucity of sequence information flanking the simple sequence repeat (SSR) motifs identified especially in the transcript sequences has been limiting factor in the development of SSR markers for plant genome analysis as well as breeding applications. To overcome this and enhance the genic SSR marker repertoire in chickpea, the draft genome sequence of kabuli chickpea (CDC Frontier) and publicly available transcript sequences consisting of in silico identified SSR motifs were deployed in the present study. In this direction, the 300 bp sequence flanking the SSR motifs were retrieved by aligning 566 SSR containing transcripts of ICCV 2 available in public domain on the reference chickpea genome. A set of 202 novel genic SSRs were developed from a set of 507 primer pairs designed, based on in silico amplification of single locus and having no similarity to the publicly available SSR markers. Further, 40 genic SSRs equally distributed on chickpea genome were validated on a select set of 44 chickpea genotypes (including 41 Cicer arietinum and 3 Cicer reticulatum), out of which 25 were reported to be polymorphic. The polymorphism information content (PIC) value of 25 polymorphic genic SSRs ranged from 0.11 to 0.77 and number of alleles varied from 2 to 9. Clear demarcation among founder lines of multi-parent advanced generation inter-cross (MAGIC) population developed at ICRISAT and near-isogenic nature of JG 11 and JG11 + demonstrates the usefulness of these markers in chickpea diversity analysis and breeding studies. Further, genic polymorphic SSRs reported between parental lines of 16 different mapping populations along with the novel SSRs can be deployed for trait mapping and breeding applications in chickpea
ROLE OF PROTECTION PROVIDED BY EMBLICA OFFICINALIS LINN. AGAINST RADIATION AND LEAD INDUCED HISTOLOGICAL CHANGES IN THE JEJUNUM OF SWISS ALBINO MICE
oai:ojs.pkp.sfu.ca:article/1Exposure to ionizing radiation increases the production of the reactive oxygen species (ROS) leading the irradiated cells into a state of oxidative stress. Furthermore, Lead exposure along with ionizing radiation can potentially become toxic to the tissues due to the heightened oxidative stress. In the present study adult male Swiss albino mice were procured and divided into seven groups. Group (II to IV) serving as control, received sub lethal dose (3.0 Gy or 6.0Gy) and /or lead acetate (20ppm) in drinking water ad libitum. The experimental groups (V to VII) were given aqueous solution of Emblica (1000 mg/ Kg b.wt./ animal/ day) orally seven days prior to radiation and/or lead acetate treatment. Sham- irradiated animals of Group I served as normal. Animals of all the groups were autopsied at each post treatment interval of 1, 2, 4, 7, 14 and 28 days. After the experiments observed number of lesions in the intestinal epithelium from outer coat to inner mucosa. Loosened sub mucosa with hyperaemia and hemorrhage, shortened crypts and a number of apoptotic cells with severe cytoplasmic variations were noted. Villi had a rough surface, wavy epithelium and hydropic degeneration up to day-2 and thereafter, a recovery from intestinal lesions was initiated and noticed till the last autopsy interval. After the combined exposure of gamma radiation and lead acetate, Group IV exhibited same pattern of damage but severe histopathological alteration than individual exposure of radiation or lead acetate indicating “synergistic “effect. Process of recovery started on day-14 after the combined treatment but the process was slow. The Combined treatment showed synergistic effect. In experimental groups less severe radiolesions and an early onset of recovery was observed. Therefore it may be deduced that Emblica is a good herbal radioprotector and may be useful for the clinical applications in human beings during radiotherapy.
Deciphering Transcriptional Programming during Pod and Seed Development Using RNA-Seq in Pigeonpea (Cajanus cajan)
Seed development is an important event in plant life cycle that has interested humankind since ages, especially in crops of economic importance. Pigeonpea is an important grain legume of the semi-arid tropics, used mainly for its protein rich seeds. In order to understand the transcriptional programming during the pod and seed development, RNA-seq data was generated from embryo sac from the day of anthesis (0 DAA), seed and pod wall (5, 10, 20 and 30 DAA) of pigeonpea variety “Asha” (ICPL 87119) using Illumina HiSeq 2500. About 684 million sequencing reads have been generated from nine samples, which resulted in the identification of 27,441 expressed genes after sequence analysis. These genes have been studied for their differentially expression, co-expression, temporal and spatial gene expression. We have also used the RNA-seq data to identify important seed-specific transcription factors, biological processes and associated pathways during seed development process in pigeonpea. The comprehensive gene expression study from flowering to mature pod development in pigeonpea would be crucial in identifying candidate genes involved in seed traits directly or indirectly related to yield and quality. The dataset will serve as an important resource for gene discovery and deciphering the molecular mechanisms underlying various seed related traits
A novel realization of the Calogero-Moser scattering states as coherent states
A novel realization is provided for the scattering states of the -particle
Calogero-Moser Hamiltonian. They are explicitly shown to be the coherent states
of the singular oscillators of the Calogero-Sutherland model. Our algebraic
treatment is straightforwardly extendable to a large number of few and
many-body interacting systems in one and higher dimensions.Comment: 9 pages, REVTe
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