Epidemiological survey of school-age children with low vision in Zhouqu County of Gannan Tibetan autonomous prefecture of Gansu province

AIM: To have a detailed picture of school-age children's eyesight status, and the main factors that caused their low vision in Zhouqu County of Gannan Tibetan autonomous prefecture of Gansu province. METHODS: The census work of knowing school-age children's eyesight status was implemented through visual inspection, conventional ophthalmic examination, optometry checks, etc. The results were compared with other domestic epidemiological data. RESULTS: Altogether 536 people with low vision were identified through survey and the rate was 21.12%. Among those people, the number of myopia patients accounted for 80.59% and the prevalence rate was 17.02%. Besides, the prevalence rate of presbyopia was 2.05%, amblyopia 2.76%, strabismus 1.02%, ocular trauma 0.95%, and congenital eye disease 0.71%. CONCLUSION: The prevalence rate of low vision was related with several factors such as gender and nationality. The rate increases with age and the myopia is the primary element that causes low vision

Construction of a cDNA library and preliminary analysis of the expressed sequence tags of the earthworm Eisenia fetida (Savigny, 1826)

Earthworms are useful indicator organisms of soil health and Eisenia fetida have been extensively used as test organisms in ecotoxicological studies. In order to gain insight into the gene expression profiles associated with physiological functions of earthworms, a full‑length enriched cDNA library of the Eisenia fetida genome was successfully constructed using Switching Mechanism at 5\u27End of RNA Template technology. Construction of a cDNA library and analysis of Expressed Sequence Tags (ESTs) are efficient approaches for collecting genomic information and identifying genes important for a given biological process. Furthermore, analysis of the expression abundance of ESTs was performed with the aim of providing genetic and transcriptomic information on the development and regenerative process of earthworms. Phrep and Crossmatch were used to process EST data and a total of 1,140 high‑quality EST sequences were determined by sequencing random cDNA clones from the library. Clustering analysis of sequences revealed a total of 593 unique sequences including 225 contiguous and 368 singleton sequences. Basic Local Alignment Search Tool analysis against the Kyoto Encyclopedia of Genes and Genomes database resulted in 593 significant hits (P‑value \u3c1x10‑8), of which 168 were annotated through Gene Ontology analysis. The STRING database was used to determine relationships among the 168 ESTs, identifying associated genes involved in protein‑protein interactions and gene expression regulation. Based on nucleic acid and protein sequence homology, the mutual relationships between 287 genes could be obtained, which identified a portion of the ESTs as known genes. The present study reports on the construction of a high‑quality cDNA library representative of adult earthworms, on a preliminary analysis of ESTs and on a putative functional analysis of ESTs. The present study is expected to enhance our understanding of the molecular basis underlying the biological development of earthworms

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Solar-Blind Ultraviolet Upwelling Radiance Diurnal Variation Led by Observation Geometry Factors on Geostationary Attitude Sensor Limb Viewing

In this satellite autonomous navigation feasibility study on geostationary orbit using the ultraviolet (UV) attitude sensor, the solar-blind UV (SBUV) upwelling radiance spatial distributions from the Earth surface points or the limb viewing path are simulated every two hours in all seasons based on the MODTRAN4 model. The target points are arranged from where the sensor can receive the Earth’s radiance, including eight limb viewing points in the 0 - 90 km altitude range with an interval of 5 km and nine surface points. A hypothetical UV attitude sensor with 9.6° field of view is set at a geostationary orbit, 3.6 × 107 m away from Equator sea level. The nadir point of which is considered to be located at 102°E and the Equator. The results show that SBUV (200 - 280 nm) upwelling radiance from the limb viewing points can increase to a maximum and then decrease with the increase in limb points altitude. The average SBUV radiance on the observation plane presents a regular bright crescent or ring, which has the maximum at about 0.433 W m-2 sr-1 μm-1 at 50 - 60 km altitude. The maximum upwelling radiance in the 242 - 267 nm spectra has the optimal characteristic considering the contrast and maximum altitude radiance continuity at the limb points

Complete mitochondrial genome of South American sea lion Otaria byronia (Carnivora: Otariidae)

The complete mitochondrial genome of Otaria byronia was sequenced for the first time. The mitogenome is 16,640 bp long and encodes 13 protein-coding genes (PCGs), 22 tRNA genes, two rRNA genes, one origin of light strand replication (OL), and a control region (CR). The overall base composition is 33.1%, 27.0%, 14.2%, and 25.7% for A, C, G, and T, respectively. The CR with 1186 bp is in the position between tRNA-Phe and tRNA-Pro genes. Phylogenetic analyses show the classification status of the pinniped species and reveal that O. byronia is grouped to the Family Otariidae

Identification of the complete mitochondrial genome of the king penguin Aptenodytes patagonicus (Sphenisciformes: Spheniscidae: Aptenodytes)

The complete mitochondrial genome of the king penguin Aptenodytes patagonicus was firstly determined. The mitogenome is 17,477 bp in length and contains 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes, and a control region. The total nucleotide composition is 31.0% A, 22.2% T, 33.1% C, and 13.8% G, with a total A + T content of 53.2%. The phylogenetic analysis demonstrates a close relationship between A. patagonicus and A. forsteri. These results provide fundamental information for further phylogeny and genetic studies on Aptenodytes genus

Comparative genomic analysis of N2-fixing and non-N2-fixing Paenibacillus spp.: organization, evolution and expression of the nitrogen fixation genes.

We provide here a comparative genome analysis of 31 strains within the genus Paenibacillus including 11 new genomic sequences of N2-fixing strains. The heterogeneity of the 31 genomes (15 N2-fixing and 16 non-N2-fixing Paenibacillus strains) was reflected in the large size of the shell genome, which makes up approximately 65.2% of the genes in pan genome. Large numbers of transposable elements might be related to the heterogeneity. We discovered that a minimal and compact nif cluster comprising nine genes nifB, nifH, nifD, nifK, nifE, nifN, nifX, hesA and nifV encoding Mo-nitrogenase is conserved in the 15 N2-fixing strains. The nif cluster is under control of a σ(70)-depedent promoter and possesses a GlnR/TnrA-binding site in the promoter. Suf system encoding [Fe-S] cluster is highly conserved in N2-fixing and non-N2-fixing strains. Furthermore, we demonstrate that the nif cluster enabled Escherichia coli JM109 to fix nitrogen. Phylogeny of the concatenated NifHDK sequences indicates that Paenibacillus and Frankia are sister groups. Phylogeny of the concatenated 275 single-copy core genes suggests that the ancestral Paenibacillus did not fix nitrogen. The N2-fixing Paenibacillus strains were generated by acquiring the nif cluster via horizontal gene transfer (HGT) from a source related to Frankia. During the history of evolution, the nif cluster was lost, producing some non-N2-fixing strains, and vnf encoding V-nitrogenase or anf encoding Fe-nitrogenase was acquired, causing further diversification of some strains. In addition, some N2-fixing strains have additional nif and nif-like genes which may result from gene duplications. The evolution of nitrogen fixation in Paenibacillus involves a mix of gain, loss, HGT and duplication of nif/anf/vnf genes. This study not only reveals the organization and distribution of nitrogen fixation genes in Paenibacillus, but also provides insight into the complex evolutionary history of nitrogen fixation

Determination of size and refractive index of single gold nanoparticles using an optofluidic chip

We report a real-time method to determine the size, i.e. diameter, and refractive index of single gold nanoparticles using an optofluidic chip, which consists of a quasi-Bessel beam optical chromatography. The tightly focused (∼ 0.5 μm) quasi-Bessel beam with low divergence (NA ∼ 0.04) was used to trap sub-100 nm gold nanoparticles within a long trapping distance of 140 μm. In the experiment, 60 to 100 nm gold nanoparticles were separated efficiently with at least 18 μm. The diameter and refractive index (real and imaginary) of single gold nanoparticles were measured at high resolutions with respect to the trapping distance, i.e. 0.36 nm/μm, 0.003/μm and 0.0016/μm, respectively.NRF (Natl Research Foundation, S’pore)Published versio

High-resolution and multi-range particle separation by microscopic vibration in an optofluidic chip

An optofluidic chip is demonstrated in experiments for high-resolution and multi-range particle separation through the optically-induced microscopic vibration effect, where nanoparticles are trapped in loosely overdamped optical potential wells created with combined optical and fluidic constraints. It is the first demonstration of separating single nanoparticles with diameters ranging from 60 to 100 nm with a resolution of 10 nm. Nanoparticles vibrate with an amplitude of 3-7 μm in the loosely overdamped potential wells in the microchannel. The proposed optofluidic device is capable of high-resolution particle separation at both nanoscale and microscale without reconfiguring the device. The separation of bacteria from other larger cells is accomplished using the same chip and operation conditions. The unique trapping mechanism and the superb performance in high-resolution and multi-range particle separation of the proposed optofluidic chip promise great potential for a diverse range of biomedical applications.NRF (Natl Research Foundation, S’pore)Accepted versio