26,136 research outputs found
Asymptotic behavior of <em>BV</em> functions and sets of finite perimeter in metric measure spaces
No full textAbstractIn this paper, we study the asymptotic behavior of BV functions in complete metric measure spaces equipped with a doubling measure supporting a 1-Poincaré inequality. We show that at almost every point x outside the Cantor and jump parts of a BV function, the asymptotic limit of the function is a Lipschitz continuous function of least gradient on a tangent space to the metric space based at x.We also show that, at co-dimension 1 Hausdorff measure almost every measure-theoretic boundary point of a set (Ε) of finite perimeter, there is an asymptotic limit set Ε∞ corresponding to the asymptotic expansion of Ε and that every such asymptotic limit (Ε)∞ is a quasiminimal set of finite perimeter. We also show that the perimeter measure of Ε∞ is Ahlfors co-dimension 1 regular. Abstract
In this paper, we study the asymptotic behavior of BV functions in complete metric measure spaces equipped with a doubling measure supporting a 1-Poincaré inequality. We show that at almost every point x outside the Cantor and jump parts of a BV function, the asymptotic limit of the function is a Lipschitz continuous function of least gradient on a tangent space to the metric space based at x.We also show that, at co-dimension 1 Hausdorff measure almost every measure-theoretic boundary point of a set (Ε) of finite perimeter, there is an asymptotic limit set Ε∞ corresponding to the asymptotic expansion of Ε and that every such asymptotic limit (Ε)∞ is a quasiminimal set of finite perimeter. We also show that the perimeter measure of Ε∞ is Ahlfors co-dimension 1 regular
Characterization of the compact operators on the class (bv,bvkθ)
No full textThe space bv, the set of all bounded variation sequences, has an important role in the summability theory. In recent study, this spaces has been extended to the space bvk? and some matrix class on this space has been characterized [2]. In the present paper, for 1 ? k ?, computing Hausdorff measure of non-compactness, we characterize compact operators in the class (bv, bvk?), where ? is a sequence of positive numbers. © 2019 Author(s)
A lower semicontinuity result for functionals on BV.
No full textIn this work the author deals with some very important problems in the calculus of variations related to the functional|
that can be considered as the natural extension to BV(Ω) of the functional
f(x,u,Du)dx, u ∈ W1,1(Ω) [see G. Dal Maso, Manuscripta Math. 30 (1979/80), no. 4, 387–416; MR0567216]. The author generalizes her results from another paper [Boll. Un. Mat. Ital. B (7) 5 (1991), no. 2, 291–313] and proves that F is lower semicontinuous, along sequences bounded in BV(Ω), relative to the strong topology of L1(Ω). The interest of the result is based on two facts: (i) the integrand f(x,s,p) is dependent on x, while in the above-mentioned paper by the author it was not so; (ii) the integrand f (x, s, p), which was supposed in Dal Maso’s paper [op. cit.] to be lower semicontinous relative to s, is not so in the present paper
A comon genomic framework for a diverse assembly of plasmids in the symbiotic nitrogen fixing bacteria
No full textThis work centres on the genomic comparisons of two closely-related nitrogen-fixing symbiotic bacteria, Rhizobium leguminosarum biovar viciae 3841 and Rhizobium etli CFN42. These strains maintain a stable genomic core that is also common to other rhizobia species plus a very variable and significant accessory component. The chromosomes are highly syntenic, whereas plasmids are related by fewer syntenic blocks and have mosaic structures. The pairs of plasmids p42f-pRL12, p42e-pRL11 and p42b-pRL9 as well large parts of p42c with pRL10 are shown to be similar, whereas the symbiotic plasmids (p42d and pRL10) are structurally unrelated and seem to follow distinct evolutionary paths. Even though purifying selection is acting on the whole genome, the accessory component is evolving more rapidly. This component is constituted largely for proteins for transport of diverse metabolites and elements of external origin. The present analysis allows us to conclude that a heterogeneous and quickly diversifying group of plasmids co-exists in a common genomic framework
Supporting safe motherhood : a review of financial trends : summary
No full textAn estimated 500,000 women, 99 percent of them from the developing world, die each year from pregnancy-related causes. About three quarters of these deaths are the direct result of obstetrical complications -- hemorrhage, infection, toxemia, obstructed labor, and abortion (under primitive and illegal conditions). An estimated equivalent number of infants do not survive their mother's death. For surviving mothers, the consequences of pregnancy have a severe impact on health and family economics. The strategy for safe motherhood is based on two approaches. First, the encouragement of activities that indirectly improve maternal health. These include education, policies to improve women's rights and working conditions, health care and nutrition, transportation and communication systems, water and sanitation facilities, and increases in family income and food production. The second approach targets activities to reduce maternal deaths. These activities include reducing unwanted pregnancies through the provision of family planning services, and through national policies that recognize the importance of this issue. A second objective is to reduce the risks of pregnancy through providing community-based family planning and prenatal services to identify high-risk cases'adequate referral services for the complications of pregnancy, and communication and transport systems to support patient referral procedures.Health Monitoring&Evaluation,Health Systems Development&Reform,Gender and Health,Early Child and Children's Health,Agricultural Knowledge&Information Systems
Company Interview: An interview with Gleb Vdovin, founder of Flexible Optical BV
No full textFlexible Optical BV is a company that has gathered some fame from the TV-show Discovery’s Project Earth, where they researched a membrane that breaks light in multiple beams. A membrane which is less than 300 nanometers thick. The idea of that project was to prevent the earth from getting too much solar energy. The membranes worked, but the journey to space was not successful.Electrical Engineering, Mathematics and Computer Scienc
A study of the ring opening metathesis polymerization of polycyclic aromatic monomers and cyclopentenes with well defined initiators
No full textThis thesis describes studies into the ring opening metathesis polymerisation (ROMP) of polycyclic aromatic monomers and cyclopentenes. Chapter 1 reviews general aspects of ring opening metathesis polymerisation of relevance to the themes of this thesis. Chapter 2 describes the synthesis of polycyclic aromatic monomers, the endo and the exo Diels-Alder adducts of acenaphthylene and cyclopentadiene. Chapter 3 reports a study on the polymerisation of these monomers using well defined initiators and classical catalyst systems. Chapter 4 describes the synthesis of a substituted cyclopentene. Chapter 5 reports an investigation of polymerisation of cyclopentene using a variety of well defined initiators of general formula M(=NAr)(- OR)(_2)(=CHR) where M=Mo or W. Chapter 6 presents a study on the polymerisation of a substituted cyclopentene, 4-methylcyclopentene, using a series of well defined initiators, and the characterisations of the polymers obtained using infrared, (^1)H, and (^13)C n.m.r. spectroscopy, differential scanning calorimetry, and gel permeation chromatography and an analysis of detailed microstructure with respect to meso/racemic configurations in the polymer chain. Finally, Chapter 7 summarises the conclusions and makes some suggestions for future work
Common fixed point on the Bv(S)-metric space of function-valued mappings
No full textIn this paper, some common fixed point results are obtained in bv(s)-metric spaces. bv(s)-metric space generalizes not only b-metric space but also rectangular metric space, v-generalized metric space and rectangular b-metric space. Examples show how these results can be applied in concrete situations. © 2021 the Author(s), licensee AIMS Press.Eusko Jaurlaritza: IT1207-19The authors would like to thank the anonymous referees for their careful reading of our manuscript and their many insightful comments and suggestions. The authors thank the Basque Government for its support of this work through Grant IT1207-19
Biliverdin-copper complex at physiological pH
No full text Biliverdin (BV), a product of heme catabolism, is known to interact with transition metals, but the details of such interactions under physiological conditions are scarce. Herein, we examined coordinate/redox interactions of BV with Cu 2+ in phosphate buffer at pH 7.4, using spectrophotometry, HESI-MS, Raman spectroscopy, 1 H NMR, EPR, fluorimetry, and electrochemical methods. BV formed a stable coordination complex with copper in 1:1 stoichiometry. The structure of BV was more planar and energetically stable in the complex. The complex showed strong paramagnetic effects that were attributed to an unpaired delocalized e - . The delocalized electron may come from BV or Cu 2+ , so the complex is formally composed either of BV radical cation and Cu 1+ or of BV radical anion and Cu 3+ . The complex underwent oxidation only in the presence of both O 2 and an excess of Cu 2+ , or a strong oxidizing agent, and it was resistant to reducing agents. The biological effects of the stable BV metallocomplex containing a delocalized unpaired electron should be further examined, and may provide an answer to the long-standing question of high energy investment in the catabolism of BV, which represents a relatively harmless molecule per se. Accepted Author ManuscriptBT/Biocatalysi
Sensible debt buybacks for highly indebted countries
No full textPrevious studies indicate that debt buybacks at market prices benefit lenders the most because the lack of a seniority structure in sovereign lending distorts secondary market prices upward. The author examines whether welfare-improving buybacks would arise at the"fair"price. If so, policy intervention is needed to remove the distortion. In a model of intertemporal consumption smoothing, buybacks at the fair price are desirable if the country experiences unusually heavy export earnings and if large reserve holdings tend to increase transfers to creditors in default states. Concerted agreements in which debt repurchases are linked to cuts in interest rates or new money requirements can make buybacks at the fair price viable, while preventing the free-rider problem among lenders.Economic Theory&Research,Banks&Banking Reform,Environmental Economics&Policies,Financial Intermediation,Strategic Debt Management
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