2,300 research outputs found

    Ideal Basis in Constructions Defined by Directed Graphs

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    The present article continues the investigation of visible ideal bases in constructions defined using directed graphs. This notion is motivated by its applications for the design of classication systems. Our main theorem establishes that, for every balanced digraph and each idempotent semiring with identity element, the incidence semiring of the digraph has a convenient visible ideal basis. It also shows that the elements of the basis can always be used to generate ideals with the largest possible weight among the weights of all ideals in the incidence semiring

    Levels of α7 integrin and laminin-α2 are increased following prednisone treatment in the mdx mouse and GRMD dog models of Duchenne muscular dystrophy

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    SUMMARY Duchenne muscular dystrophy (DMD) is a fatal neuromuscular disease for which there is no cure and limited treatment options. Prednisone is currently the first line treatment option for DMD and studies have demonstrated that it improves muscle strength. Although prednisone has been used for the treatment of DMD for decades, the mechanism of action of this drug remains unclear. Recent studies have shown that the α7β1 integrin is a major modifier of disease progression in mouse models of DMD and is therefore a target for drug-based therapies. In this study we examined whether prednisone increased α7β1 integrin levels in mdx mouse and GRMD dog models and myogenic cells from humans with DMD. Our results show that prednisone promotes an increase in α7 integrin protein in cultured myogenic cells and in the muscle of mdx and GRMD animal models of DMD. The prednisone-mediated increase in α7 integrin was associated with increased laminin-α2 in prednisone-treated dystrophin-deficient muscle. Together, our results suggest that prednisone acts in part through increased merosin in the muscle basal lamina and through sarcolemmal stabilization of α7β1 integrin in dystrophin-deficient muscle. These results indicate that therapies that target an increase in muscle α7β1 integrin, its signaling pathways and/or laminin could be therapeutic in DMD

    An Experimental Investigation of Conformational Fluctuations in Proteins G and L

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    SummaryThe B1 domains of streptococcal proteins G and L are structurally similar, but they have different sequences and they fold differently. We have measured their NMR spectra at variable temperature using a range of concentrations of denaturant. Many residues have curved amide proton temperature dependence, indicating that they significantly populate alternative, locally unfolded conformations. The results, therefore, provide a view of the locations of low-lying, locally unfolded conformations. They indicate approximately 4–6 local minima for each protein, all within ca. 2.5 kcal/mol of the native state, implying a locally rough energy landscape. Comparison with folding data for these proteins shows that folding involves most molecules traversing a similar path, once a transition state containing a β hairpin has been formed, thereby defining a well-populated pathway down the folding funnel. The hairpin that directs the folding pathway differs for the two proteins and remains the most stable part of the folded protein

    Genetic Diversity in Hypericum and AFLP Markers for Species-Specific Identification of H. perforatum L.

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    One of the top-selling medicinal products worldwide is Hypericum perforatum (St. John\u27s Wort). Despite its cosmopolitan distribution and utilization, little is known regarding the relationship of the bioactive compounds in H. perforatum to the plants from which they are purportedly derived. In this study, amplified fragment length polymorphism (AFLP) analysis of 56 Hypericum accessions, representing 11 species, was conducted to gain a better understanding of diversity within Hypericum species, especially within cultivated accessions of H. perforatum, and to establish a molecular methodology that will provide breeders and regulators with a simple, affordable, and accurate tool with which to identify purported H. perforatummaterial. Utilizing four primer combinations, a total of 298 polymorphic markers were generated, of which 17 were present in all H. perforatum accessions and 2 were specific to only H. perforatum. This study demonstrates that AFLP can be utilized not only to determine the relationships of closely related Hypericumaccessions, but as a tool to authenticate material in herbal remedies through the use of genetic fingerprinting

    Economics of pasture-based dairies (2012)

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    "Agriculture.""Dairy grazing.""Dairy grazing publication series: This publication is one in a series about operating and managing a pasture-based dairy. Although these publications often refer to conditions in Missouri, many of the principles and concepts described may apply to operations throughout the United States. A list of the publications in this series is available online at http://extension.missouri.edu/m168.""Revised from M168, Dairy Grazing Manual, by Joe Horner, Dairy Economist, Commercial Agriculture Program, Ryan Milhollin, Project Manager, Commercial Agriculture Program, Wayne Prewitt, West Central Region Agriculture Business Specialist.""This publication replaces Chapter 14, Economics of a Pasture-Based Dairy, in MU Extension publication M168, Dairy Grazing Manual. Original authors: Stacey A. Hamilton, Greg J. Bishop-Hurley and Ron Young, University of Missouri."New 2/12/Web

    Protecting private information for two classes of aggregated database queries

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    An important direction of informatics is devoted to the protection of privacy of confidential information while providing answers to aggregated queries that can be used for analysis of data. Protecting privacy is especially important when aggregated queries are used to combine personal information stored in several databases that belong to different owners or come from different sources. Malicious attackers may be able to infer confidential information even from aggregated numerical values returned as answers to queries over large collections of data. Formal proofs of security guarantees are important, because they can be used for implementing practical systems protecting privacy and providing answers to aggregated queries. The investigation of formal conditions which guarantee protection of private information against inference attacks originates from a fundamental result obtained by Chin and Ozsoyoglu in 1982 for linear queries. The present paper solves similar problems for two new classes of aggregated nonlinear queries. We obtain complete descriptions of conditions, which guarantee the protection of privacy of confidential information against certain possible inference attacks, if a collection of queries of this type are answered. Rigorous formal security proofs are given which guarantee that the conditions obtained ensure the preservation of privacy of confidential data. In addition, we give necessary and sufficient conditions for the protection of confidential information from special inference attacks aimed at achieving a group compromise

    Polyglycolic acid microneedles modified with inkjet-deposited antifungal coatings

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    In this study, the authors examined use of piezoelectric inkjet printing to apply an antifungal agent, voriconazole, to the surfaces of biodegradable polyglycolic acid microneedles. Polyglycolic acid microneedles with sharp tips (average tip radius = 25 ± 3 μm) were prepared using a combination of injection molding and drawing lithography. The elastic modulus (9.9 ± 0.3 GPa) and hardness (588.2 ± 33.8 MPa) values of the polyglycolic acid material were determined using nanoindentation and were found to be suitable for use in transdermal drug delivery devices. Voriconazole was deposited onto the polyglycolic acid microneedles by means of piezoelectric inkjet printing. It should be noted that voriconazole has poor solubility in water; however, it is readily soluble in many organic solvents. Optical imaging, scanning electron microscopy, energy dispersive x-ray spectrometry, and Fourier transform infrared spectroscopy were utilized to examine the microneedle geometries and inkjet-deposited surface coatings. F..

    Epitope Recognition in HLA-DR3 Transgenic Mice Immunized to TSH-R Protein or Peptides

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    Development of Graves\u27 disease is related to HLA-DR3. The extracellular domain (ECD) of human TSH receptor (hTSH-R) is a crucial antigen in Graves\u27 disease. hTSH-R peptide 37 (amino acids 78–94) is an important immunogenic peptide in DR3 transgenic mice immunized to hTSH-R. This study examined the epitope recognition in DR3 transgenic mice immunized to hTSH-R protein and evaluated the ability of a mutant hTSH-R peptide to attenuate the immunogenicity of hTSH-R peptide 37. DR3 transgenic mice were immunized to recombinant hTSH-R-ECD protein or peptides. A mutant hTSH-R 37 peptide (ISRIYVSIDATLSQLES: 37m), in which DR3 binding motif position 5 was mutated V\u3eA, and position 8 Q\u3eS, was synthesized. 37m should bind to HLA-DR3 but not bind T cell receptors. DR3 transgenic mice were immunized to hTSH-R 37 and 37m. Mice immunized to hTSH-R-ECD protein developed strong anti-hTSH-R antibody, and antisera reacted strongly with hTSH-R peptides 1–5 (20–94), 21 (258–277), 41 (283–297), 36 (376–389), and 31 (399–418). Strikingly, antisera raised to hTSH-R peptide 37 bound to hTSH-R peptides 1–7 (20–112), 10 (132–50), 33 (137–150), 41, 23 (286–305), 24 (301–320), 36, and 31 as well as to hTSH-R-ECD protein. Both antibody titers to hTSH-R 37 and reaction of splenocytes to hTSH-R 37 were significantly reduced in mice immunized to hTSH-R 37 plus 37m, compared with mice immunized to hTSH-R 37 alone. The ability of immunization to a single peptide to induce antibodies that bind hTSH-R-ECD protein, and multiple unrelated peptides, is a unique observation. Immunogenic reaction to hTSH-R peptide 37 was partially suppressed by 37m, and this may contribute to immunotherapy of autoimmune thyroid disease

    To play or not to play: Can an instrument really impact lip and tongue performance?

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    © 2020 by the authors. Licensee MDPI, Basel, Switzerland. (1) Background: Increasing tongue and lip strength may help improve various speech and swallowing disorders, but it is unclear if instrumentalists who use these muscle groups for long periods of time have greater strength and endurance compared to controls. It is also unclear if instrumentalists can more accurately estimate various exercise intensities. The purpose of this study was to determine differences in lip and tongue strength and endurance between instrumentalists and non-instrumentalists (controls). A secondary purpose was to assess differences in ability to estimate various exercise intensities between the two groups. (2) Methods: Instrumentalists and controls’ maximum strength and endurance were measured using the IOPI Pro medical device. In addition, 40%, 60% and 80% of maximum strength were estimated in a randomized order. (3) Results: No significant differences were found between instrumentalists and controls in strength or endurance or the ability to estimate various intensities. Overall, participants were better at estimating tongue strength at moderate intensities and lip strength at higher intensities. (4) Conclusion: Tongue and lip strength and endurance and the ability to estimate exercise intensities are not impacted by years of instrumentalist training compared to healthy controls

    Evidence for He I 10830 \AA~ absorption during the transit of a warm Neptune around the M-dwarf GJ 3470 with the Habitable-zone Planet Finder

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    Understanding the dynamics and kinematics of out-flowing atmospheres of hot and warm exoplanets is crucial to understanding the origins and evolutionary history of the exoplanets near the evaporation desert. Recently, ground based measurements of the meta-stable Helium atom's resonant absorption at 10830 \AA~has become a powerful probe of the base environment which is driving the outflow of exoplanet atmospheres. We report evidence for the He I 10830 \AA~in absorption (equivalent width ∼\sim 0.012±0.0020.012 \pm 0.002 \AA) in the exosphere of a warm Neptune orbiting the M-dwarf GJ 3470, during three transits using the Habitable Zone Planet Finder (HPF) near infrared spectrograph. This marks the first reported evidence for He I 10830 \AA\, atmospheric absorption for a planet orbiting an M-dwarf. Our detected absorption is broad and its blueshifted wing extends to -36 km/sec, the largest reported in the literature to date. We modelled the state of Helium atoms in the exosphere of GJ3470b based on assumptions on the UV and X-ray flux of GJ 3470, and found our measurement of flux-weighted column density of meta-stable state Helium (NHe32S=2.4×1010cm−2)(N_{He^2_3S} = 2.4 \times 10^{10} \mathrm{cm^{-2}}), derived from our transit observations, to be consistent with model, within its uncertainties. The methodology developed here will be useful to study and constrain the atmospheric outflow models of other exoplanets like GJ 3470b which are near the edge of the evaporation desert.Comment: Accepted in Ap
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