1,903 research outputs found
Computation of the inverse Laplace Transform based on a Collocation method which uses only real values
We develop a numerical algorithm for inverting a Laplace transform (LT), based on Laguerre polynomial series expansion of the
inverse function under the assumption that the LT is known on the real axis only. The method belongs to the class of Collocation
methods (C-methods), and is applicable when the LT function is regular at infinity. Difficulties associated with these problems are due
to their intrinsic ill-posedness. The main contribution of this paper is to provide computable estimates of truncation, discretization,
conditioning and roundoff errors introduced by numerical computations. Moreover, we introduce the pseudoaccuracy which will be
used by the numerical algorithm in order to provide uniform scaled accuracy of the computed approximation for any x with respect
to ex . These estimates are then employed to dynamically truncate the series expansion. In other words, the number of the terms of
the series acts like the regularization parameter which provides the trade-off between errors.
With the aim to validate the reliability and usability of the algorithm experiments were carried out on several test functions
Effect of Martian Suspended Dust on Albedo Measurements from the MGS-TES Data
Suspended dust on Mars influences albedo measurements by orbiting instruments, but not necessary the real surface albedo. The aim of this study is to characterize the role of suspended aerosols on albedo measurement by remote sensing instruments
Synthesis and Biological Characterization of a New Norbormide Derived Bodipy FL-Conjugated Fluorescent Probe for Cell Imaging
Background: Norbormide (NRB) is a selective rat toxicant endowed with vasoconstrictor activity confined to the rat peripheral arteries. In a recent work we used a fluorescent derivative of NRB (NRB-AF12), obtained by coupling the NBD fluorophore to the parent molecule via a linker, in order to gain information about the possible site of action of the unlabeled compound. We found that NRB-AF12 labeled intracellular organelles in both NRB-sensitive and -insensitive cells and we accordingly proposed its use as a scaffold for the development of a new class of fluorescent probes. In this study, we examined the fluorescent properties of a BODIPY FL-conjugated NRB probe (MC009) developed: (A) to verify if NRB distribution could be influenced by the attached fluorophore; (B) to improve the fluorescent performance of NRB-AF12. Methods: MC009 characteristics were investigated by confocal fluorescence microscopy, in freshly isolated rat caudal artery myocytes (FIRCAM) and in LX2 cells, representative of NRB-sensitive and insensitive cells, respectively. Main results: In both FIRCAM and LX2 cells MC009 stained endoplasmic reticulum, mitochondria, Golgi apparatus and lipid droplets, revealing the same intracellular distribution as NRB-AF12, and, at the same time, had both improved photostability and gave a more intense fluorescent signal at lower concentrations than was possible with NRB-AF12, which resulted in a better and finer visualization of intracellular structures. Furthermore, MC009 was effective in cellular labeling in both living and fixed cells. At the concentration used to stain the cells, MC009 did not show any cytotoxic effect and did not affect the regular progression of cell cycle and division. Conclusions: This study demonstrates that the distribution of fluorescently labeled NRB is not affected by the type of fluorophore attached to the parent compound, supporting the idea that the localization of the fluorescent derivatives may reasonably reflect that of the parent compound. In addition, we observed a marked improvement in the fluorescent properties of BODIPY FL-conjugated NRB (MC009) over its NBD-derived counterpart (NRB-AF12), confirming NRB as a scaffold for the development of new, high performance, non-toxic fluorescent probes for the labeling of intracellular structures in both living and fixed cells
Infrared absorption from Charge Density Waves in magnetic manganites
The infrared absorption of charge density waves coupled to a magnetic
background is first observed in two manganites La{1-x}Ca{x}MnO{3} with x = 0.5
and x = 0.67. In both cases a BCS-like gap 2 Delta (T), which for x=0.5 follows
the hysteretic ferro-antiferromagnetic transition, fully opens at a finite T{0}
< T{Neel}, with 2 Delta(T{0})/kT{c} close to 5. These results may also explain
the unusual coexistence of charge ordering and ferromagnetism in
La{0.5}Ca{0.5}MnO{3}.Comment: File revtex + 3 figs. in epsf. To appear on Phys. Rev. Let
Stem-like and highly invasive prostate cancer cells expressing CD44v8-10 marker originate from CD44-negative cells
In human prostate cancer (PCa), the neuroendocrine cells, expressing the prostate cancer stem cell (CSC) marker CD44, may be resistant to androgen ablation and promote tumor recurrence. During the study of heterogeneity of the highly aggressive neuroendocrine PCa cell lines PC3 and DU-145, we isolated and expanded in vitro a minor subpopulation of very small cells lacking CD44 (CD44neg). Unexpectedly, these sorted CD44neg cells rapidly and spontaneously converted to a stable CD44high phenotype specifically expressing the CD44v8-10 isoform which the sorted CD44high subpopulation failed to express. Surprisingly and potentially interesting, in these cells expression of CD44v8-10 was found to be induced in stem cell medium. CD44 variant isoforms are known to be more expressed in CSC and metastatic cells than CD44 standard isoform. In agreement, functional analysis of the two sorted and cultured subpopulations has shown that the CD44v8-10pos PC3 cells, resulting from the conversion of the CD44neg subpopulation, were more invasive in vitro and had a higher clonogenic potential than the sorted CD44high cells, in that they produced mainly holoclones, known to be enriched in stem-like cells. Of interest, the CD44v8-10 is more expressed in human PCa biopsies than in normal gland. The discovery of CD44v8-10pos cells with stem-like and invasive features, derived from a minoritarian CD44neg cell population in PCa, alerts on the high plasticity of stem-like markers and urges for prudency on the approaches to targeting the putative CSC
Identification of homozygous deletion in ACAN and other candidate variants in familial classical Hodgkin lymphoma by exome sequencing
Tutkimuksessamme tarkastelimme Lähi-idästä lähtöisin olevaa perhettä, jossa kolmella viidestä lapsesta on todettu nuorellä iällä klassinen Hodgkinin lymfooma (cHL). Perinnöllinen alttius cHL:lle tunnetaan huonosti, eikä taudille mahdollisesti altistavia geenimuutoksia ole aiemmin raportoitui kuin yksi kappale. Geenimuutosten selvittämiseksi eksomisekvensoimme kolmen sairastuneen lapsen verinäytteestä eristetyn DNA:n ja poimimme joukosta kaikkien kolmen jakamat muutokset. Suodatimme lasten jakamien DNA-muutosten joukosta pois omissa vertailujoukoissamme ja useissa julkisissa tietokannoissa esiintyvät geneettiset muutokset ja arvioimme jäljellejääneiden muutosten haitallisuutta kahdella laskennallisella priorisaatioalgoritmilla. Näin saimme järjestettyä jäljelle jääneet 35 jaettua muutosta laskennalliseen haitallisuusjärjestykseen. Jaetuista muutoksista merkittävimmäksi nousi ACAN-geenissä oleva homotsygoottinen 57 emäksen pituinen deleetio c.2836_2892del, jota ei ole aiemmin liitytty cHL-fenotyyppiin
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Are Meaningful Use Stage 2 certified EHRs ready for interoperability? Findings from the SMART C-CDA Collaborative
Background and objective Upgrades to electronic health record (EHR) systems scheduled to be introduced in the USA in 2014 will advance document interoperability between care providers. Specifically, the second stage of the federal incentive program for EHR adoption, known as Meaningful Use, requires use of the Consolidated Clinical Document Architecture (C-CDA) for document exchange. In an effort to examine and improve C-CDA based exchange, the SMART (Substitutable Medical Applications and Reusable Technology) C-CDA Collaborative brought together a group of certified EHR and other health information technology vendors. Materials and methods We examined the machine-readable content of collected samples for semantic correctness and consistency. This included parsing with the open-source BlueButton.js tool, testing with a validator used in EHR certification, scoring with an automated open-source tool, and manual inspection. We also conducted group and individual review sessions with participating vendors to understand their interpretation of C-CDA specifications and requirements. Results: We contacted 107 health information technology organizations and collected 91 C-CDA sample documents from 21 distinct technologies. Manual and automated document inspection led to 615 observations of errors and data expression variation across represented technologies. Based upon our analysis and vendor discussions, we identified 11 specific areas that represent relevant barriers to the interoperability of C-CDA documents. Conclusions: We identified errors and permissible heterogeneity in C-CDA documents that will limit semantic interoperability. Our findings also point to several practical opportunities to improve C-CDA document quality and exchange in the coming years
Neuropilin 1 expression correlates with differentiation status of epidermal cells and cutaneous squamous cell carcinomas
Neuropilins (NRP) are cell surface receptors for VEGF and SEMA3 family members. The role of NRP in neurons and endothelial cells has been investigated, but the expression and role of NRP in epithelial cells is much less clear. Herein, the expression and localization of neuropilin 1 (NRP1) was investigated in human and mouse skin and squamous cell carcinomas (SCC). Results indicated that NRP1 mRNA and protein was expressed in the suprabasal epithelial layers of skin sections. NRP1 staining did not overlap with that of keratin 14 (K14) or proliferating cell nuclear antigen, but did colocalize with staining for keratin 1, indicating that differentiated keratinocytes express NRP1. Similar to the expression of NRP1, VEGF-A was expressed in suprabasal epithelial cells, whereas Nrp2 and VEGFR2 were not detectable in the epidermis. The expression of NRP1 correlated with a high degree of differentiation in human SCC specimens, human SCC xenografts, and mouse K14-HPV16 transgenic SCC. UVB irradiation of mouse skin induced Nrp1 upregulation. In vitro, Nrp1 was upregulated in primary keratinocytes in response to differentiating media or EGF-family growth factors. In conclusion, the expression of NRP1 is regulated in the skin and is selectively produced in differentiated epithelial cells. NRP1 may function as a reservoir to sequester VEGF ligand within the epithelial compartment, thereby modulating its bioactivity
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Therapeutic angiogenesis for cardiovascular disease
The identification of angiogenic growth factors, such as vascular endothelial growth factor and fibroblast growth factor, has fueled interest in using such factors to induce therapeutic angiogenesis. The results of numerous animal studies and clinical trials have offered promise for new treatment strategies for various ischemic diseases. Increased understanding of the cellular and molecular biology of vessel growth has, however, prompted investigators and clinicians alike to reconsider the complexity of therapeutic angiogenesis. The realization that formation of a stable vessel is a complex, multistep process may provide useful insights into the design of the next generation of angiogenesis therapy
Comparison of referring and final pathology for patients with T‐cell lymphoma in the National Comprehensive Cancer Network
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/107537/1/cncr28676.pd
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