455 research outputs found

    Evaluation of entropy and JM-distance criterions as features selection methods using spectral and spatial features derived from LANDSAT images

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    A study area near Ribeirao Preto in Sao Paulo state was selected, with predominance in sugar cane. Eight features were extracted from the 4 original bands of LANDSAT image, using low-pass and high-pass filtering to obtain spatial features. There were 5 training sites in order to acquire the necessary parameters. Two groups of four channels were selected from 12 channels using JM-distance and entropy criterions. The number of selected channels was defined by physical restrictions of the image analyzer and computacional costs. The evaluation was performed by extracting the confusion matrix for training and tests areas, with a maximum likelihood classifier, and by defining performance indexes based on those matrixes for each group of channels. Results show that in spatial features and supervised classification, the entropy criterion is better in the sense that allows a more accurate and generalized definition of class signature. On the other hand, JM-distance criterion strongly reduces the misclassification within training areas

    A second consensus sequence of ATP-requiring proteins resides in the 21-kDa C-terminal segment of myosin subfragment 1

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    AbstractPrevious comparisons of sequence homologies of ATP-requiring enzymes have defined three consensus sequences which appear to be involved in the binding of the nucleotide. One of these was identified in the N-terminal 27-kDa segment of the myosin heavy chain but the other two sequences have not hitherto been located in myosin. The present paper proposes that one of these other two consensus sequences is in the 21-kDa C-terminal portion of S1 and that it may contribute to the ATP binding domain

    An integrated software system for geometric correction of LANDSAT MSS imagery

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    A system for geometrically correcting LANDSAT MSS imagery includes all phases of processing, from receiving a raw computer compatible tape (CCT) to the generation of a corrected CCT (or UTM mosaic). The system comprises modules for: (1) control of the processing flow; (2) calculation of satellite ephemeris and attitude parameters, (3) generation of uncorrected files from raw CCT data; (4) creation, management and maintenance of a ground control point library; (5) determination of the image correction equations, using attitude and ephemeris parameters and existing ground control points; (6) generation of corrected LANDSAT file, using the equations determined beforehand; (7) union of LANDSAT scenes to produce and UTM mosaic; and (8) generation of output tape, in super-structure format

    Compact Einstein Spaces based on Quaternionic K\"ahler Manifolds

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    We investigate the Einstein equation with a positive cosmological constant for 4n+44n+4-dimensional metrics on bundles over Quaternionic K\"ahler base manifolds whose fibers are 4-dimensional Bianchi IX manifolds. The Einstein equations are reduced to a set of non-linear ordinary differential equations. We numerically find inhomogeneous compact Einstein spaces with orbifold singularity.Comment: LaTeX 28 pages, 5 eps figure

    A scalable lysyl hydroxylase 2 expression system and luciferase-based enzymatic activity assay

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    Hydroxylysine aldehyde-derived collagen cross-links (HLCCs) accumulate in fibrotic tissues and certain types of cancer and are thought to drive the progression of these diseases. HLCC formation is initiated by lysyl hydroxylase 2 (LH2), an Fe(II) and α-ketoglutarate (αKG)-dependent oxygenase that hydroxylates telopeptidyl lysine residues on collagen. Development of LH2 antagonists for the treatment of these diseases will require a reliable source of recombinant LH2 protein and a non-radioactive LH2 enzymatic activity assay that is amenable to high throughput screens of small molecule libraries. However, LH2 protein generated previously using E coli– or insect-based expression systems was either insoluble or enzymatically unstable, and LH2 enzymatic activity assays have measured radioactive CO2 released from 14C-labeled αKG during its conversion to succinate. To address these deficiencies, we have developed a scalable process to purify human LH2 protein from Chinese hamster ovary cell-derived conditioned media samples and a luciferase-based assay that quantifies LH2-dependent conversion of αKG to succinate. These methodologies may be applicable to other Fe(II) and αKG-dependent oxygenase systems

    A new liver perfusion and preservation system for transplantation Research in large animals

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    A kidney perfusion machine, model MOX-100 (Waters Instruments, Ltd, Rochester, MN) was modified to allow continuous perfusion of the portal vein and pulsatile perfusion of the hepatic artery of the liver. Additional apparatus consists of a cooling system, a membrane oxygenator, a filter for foreign bodies, and bubble traps. This system not only allows hypothermic perfusion preservation of the liver graft, but furthermore enables investigation of ex vivo simulation of various circulatory circumstances in which physiological perfusion of the liver is studied. We have used this system to evaluate the viability of liver allografts preserved by cold storage. The liver was placed on the perfusion system and perfused with blood with a hematocrit of approximately 20% and maintained at 37°C for 3 h. The flows of the hepatic artery and portal vein were adjusted to 0.33 mL and 0.67 mL/g of liver tissue, respectively. Parameters of viability consisted of hourly bile output, oxygen consumption, liver enzymes, electrolytes, vascular resistance, and liver histology. This method of liver assessment in large animals will allow the objective evaluation of organ viability for transplantation and thereby improve the outcome of organ transplantation. Furthermore, this pump enables investigation into the pathophysiology of liver ischemia and preservation. © 1990 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted

    KLF11 and association study in Japanese

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    Aims: Krüppel-like factor 11 (KLF11) is a transcriptional factor of the zinc finger domain family that regulates the expression of insulin. In North European populations, its common functional variant Q62R (rs35927125) is a strong genetic factor for Type 2 diabetes (P = 0.00033, odds ratio for G allele = 1.29, 95% CI 1.12–1.49). We examined the contribution of KLF11 variants to the susceptibility to Type 2 diabetes in a Japanese population. Methods: By re-sequencing Japanese individuals (n = 24, partly 96), we screened all four exons, exon/intron boundaries and flanking regions of KLF11. Verified single nucleotide polymorphisms (SNPs) were genotyped in 731 initial samples (369 control and 362 case subjects). Subsequently, we tested for association in 1087 samples (524 control and 563 case subjects), which were collected in different districts of Japan from the initial samples. Results: We identified eight variants, including a novel A/C variant on intron 3, but no mis-sense mutations. In an association study, we failed to find any significant result of SNPs (minor allele frequency 8.2–46.2%) after correcting for multiple testing. Similarly, no haplotypes were associated with Type 2 diabetes. It is notable that the G allele in rs35927125 was completely absent in 1818 Japanese individuals. Conclusions: Genetic variants in KLF11 are unlikely to have a major effect of Type 2 diabetes in the Japanese population, although they were significantly associated in North European populations. These observations might help to determine the role of KLF11 variants in Type 2 diabetes in different populations

    Double bundle arthroscopic Anterior Cruciate Ligament reconstruction with remnant preserving technique using a hamstring autograft

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    <p>Abstract</p> <p>Background</p> <p>Preservation of the Anterior Cruciate Ligament (ACL) remnant is important from the biological point of view as it enhances revascularization, and preserves the proprioceptive function of the graft construct. Additionally, it may have a useful biomechanical function. Double bundle ACL reconstruction has been shown to better replicate the native ACL anatomy and results in better restoration of the rotational stability than single bundle reconstruction.</p> <p>Methods</p> <p>We used the far anteromedial (FAM) portal for creation of the femoral tunnels, with a special technique for its preoperative localization using three dimensional (3D) CT. The central anteromedial (AM) portal was used to make a longitudinal slit in the ACL remnant to allow visualization of the tips of the guide pins during anatomical creation of the tibial tunnels within the native ACL tibial foot print. The use of curved hemostat allow retrieval of the wire loop from the apertures of the femoral tunnels through the longitudinal slit in the ACL remnant thereby, guarding against impingement of the reconstruction graft against the ACL remnant as well as the roof of the intercondylar notch.</p> <p>Conclusion</p> <p>Our technique allows for anatomical double bundle reconstruction of the ACL while maximally preserving the ACL remnant without the use of intra-operative image intensifier.</p
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