427 research outputs found

    Inverse spectral problems for non-selfadjoint second-order differential operators with Dirichlet boundary conditions

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    [[abstract]]We study the inverse problem for non-selfadjoint Sturm-Liouville operators on a finite interval with possibly multiple spectra. We prove the uniqueness theorem and obtain constructive procedures for solving the inverse problem along with the necessary and sufficient conditions of its solvability and also prove the stability of the solution.[[journaltype]]國外[[incitationindex]]SCI[[ispeerreviewed]]Y[[booktype]]電子版[[countrycodes]]DE

    Peptides as potent antimicrobials tethered to a solid surface: Implications for medical devices

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    Medical devices are an integral part of therapeutic management; despite their importance, they carry a significant risk of microbial infection. Bacterial attachment to a medical device is established by a single, multiplying organism, leading to subsequent biofilm formation. To date, no preventative measures have impacted the incidence of device-related infection. We report the bidirectional covalent coupling of an engineered cationic antimicrobial peptide (eCAP), WLBU2, to various biological surfaces is accomplished. These surfaces included (i) a carbohydrate-based gel matrix, (ii) a complex polymeric plastic bead, and (iii) a silica-calcium phosphate nanocomposite associated with bone reconstruction. WLBU2-conjugated surfaces are shown to retain potent antimicrobial activity related to bacterial surface adhesion. This study provides proof of principle that covalently coating laboratory and bone-regenerating materials with eCAPs has the potential for decreasing infection rates of implanted devices. These findings have important consequences to the patient management component of our current health care technology

    Assessing the Impact of the Maternity Capital Policy in Russia Using a Dynamic Model of Fertility and Employment

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    With declining population and fertility rates below replacement levels, Russia is currently facing a demographic crisis. Starting in 2007, the federal government has pursued an ambitious pro-natalist policy. Women who give birth to at least two children are entitled to "maternity capital" assistance ($11,000). In this paper we estimate a structural dynamic programming model of fertility and labor force participation in order to evaluate the effectiveness of the policy. We find that the program increased long-run fertility by about 0.15 children per woman

    Commercial development of the semi-solid rheocasting (ssrtm) process

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    Rheocasting processes create non-dendritic, equiaxed microstructure suitable for semi-solid forming directly from liquid aluminum alloy. A new rheocasting technology that efficiently creates non-dendritic material was developed at the Massachusetts Institute of Technology in 2000 and discussed at the previous NADCA Congress in Cincinnati in 2001. In early 2002, Idra Casting Machines acquired the exclusive license from M.I.T. to develop and sell casting equipment utilizing the technology.Now known as Semi-Solid Rheocasting (SSRTM), the process has undergone development from the laboratory to a commercial machine. Designed as a retrofit for die casting machines, the rheocast machine allows die casters to not only increase part quality and make safety critical castings, but also to decrease cycle time and increase tool life. In this paper, the SSRTM station will be described in detail, and advantages of the process will be discussed

    Relapses In multiple sclerosis.

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    Exact causes of contradictions in the understanding of relapsing course as characteristic phenomenon of multiple sclerosis (MS) and primarily relapsing-remitting type are still considered to be “sub rosa”. We tried to determine connection and correlation between seasonal dynamic factors, chronometric parameters of disease progression (age, disease duration) and frequency of relapses and the role of gender differences as well. A four-year prospective study included complete registration of all cases of MS exacerbations in resident patients with a relapsing-remmiting course of the disease according to McDonald criteria in Volyn region of Ukraine in 2010. Each patient had neurological score based on EDSS scale to ensure compliance with inclusion criteria. 128 patients (44 males and 84 females) with a remitting-recurring course of the disease were involved in this study. Statistical analysis was performed using SPSS 18, MedCalc and Microsoft Excel software using standard descriptive statistics, correlation and regression analysis. In total, 197 cases of MS relapses were registered. Episodes of relapses prevailed in winter-spring period. Multiple regression model including suggested climate factors showed multiple correlation coefficient – 0.55 (p<0.01). The prevalence of MS was higher in females, while general incidence of recurrences was similar to males. However, relapse rate in different age groups differs: the rate of recurrence increases in women aged after 50 years (mean annualized relapse rate (ARR)=0.66), while it slowly decreases in men with aging. The duration of the disease did not have significant effect on the course of MS in women, whereas weak negative relationship (0.24, p<0.001) between the duration of the disease and the frequency of MS in men was showed. Correspondingly, the average negative correlation (-0.37, p<0.001) was detected between the age of disease onset and the incidence of MS recurrence in males, while this connection was not observed in females. We established that the recurrence of MS is a result of multifactorial influence of external and internal factors. Individual seasonal climate variability did not have sufficient force of influence. Therefore, combined effect of corresponding climate changes played a significant role. Furthermore, it is quite probable that interactions of MS with external factors influencing the human body can be mutually integrated

    СУЧАСНИЙ СТАН ТА ТЕНДЕНЦІЇ РОЗВИТКУ ІНВЕСТИЦІЙНОЇ ДІЯЛЬНОСТІ У СІЛЬСЬКОМУ ГОСПОДАРСТВІ УКРАЇНИ

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    Globalization processes accelerate the pace of scientific and technological progress and innovation and require investment in innovation to enhance the efficiency of the national economy of our state and some of its branches, inter–industry complexes and sub–complexes at the level of developed countries.The article examines the current state of investment in agriculture of Ukraine. The main criteria to encourage capital investment taking into account regional peculiarities capital investment in agriculture. The necessity of attracting external sources of investment in the future to enhance investment processes in agriculture.Thus, the study of the current situation of investment activity of agricultural enterprises of Ukraine and structural analysis of sources of investment in agriculture, to determine that the trend of improving investment for 2010–2014., Changed deterioration in 2015 and complication of financing conditions from their own field investment. So one of the essential ways to increase the competitiveness of the industry is an effective investment policy aimed at attracting large–scale foreign investment sources, especially through financial investment. Addressing these and other issues will significantly increase investment flows and rational use of funds in the industry.В статье рассмотрено современное состояние инвестиционной деятельности в сельском хозяйстве Украины. Определены основные критерии поощрения капитальных инвестиций с учетом региональных особенностей капитального инвестирования в сельское хозяйство. Обоснована необходимость привлечения внешних источников инвестиций в перспективе с целью активизации инвестиционных процессов в сельскохозяйственной отраслиУ статті розглянуто сучасний стан інвестиційної діяльності в сільському господарстві України. Визначено основні критерії заохочення капітальних інвестицій з урахуванням регіональних особливостей капітального інвестування в сільське господарство. Обґрунтовано необхідність залучення зовнішніх джерел інвестицій у перспективі з метою активізації інвестиційних процесів у сільськогосподарській галузі

    Estimates of complex eigenvalues and an inverse spectral problem for the transmission eigenvalue problem

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    This work deals with the interior transmission eigenvalue problem: y 00 + k 2η (r) y = 0 with boundary conditions y (0) = 0 = y 0 (1) sin k k − y (1) cos k, where the function η(r) is positive. We obtain the asymptotic distribution of non-real transmission eigenvalues under the suitable assumption on the square of the index of refraction η(r). Moreover, we provide a uniqueness theorem for the case R 1 0 p η(r)dr > 1, by using all transmission eigenvalues (including their multiplicities) along with a partial information of η(r) on the subinterval. The relationship between the proportion of the needed transmission eigenvalues and the length of the subinterval on the given η(r) is also obtained

    Photoinduced magnetic linear dichroism in a YIG:Co film

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    The spectra of linear dichroism induced by magnetic field are observed in a cobalt-doped yttrium iron garnet (YIG:Co) film grown in the (001) plane. The linear dichroism spectra are highly sensitive to the orientation of the magnetic field. The spectrum measured with the magnetic field directed along the crystallographic axis [100] turned out to have a form identical to the spectrum of the "rigid" photoinduced linear dichroism, known from earlier experiments. The similarity of these spectra may be regarded a sevidence of the magnetic origin of the major part of the optical anisotropy induced by light with polarization E | | [100] in the nonmagnetized YIG:Co film

    Inverse spectral problems for Sturm--Liouville operators with matrix-valued potentials

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    We give a complete description of the set of spectral data (eigenvalues and specially introduced norming constants) for Sturm--Liouville operators on the interval [0,1][0,1] with matrix-valued potentials in the Sobolev space W21W_2^{-1} and suggest an algorithm reconstructing the potential from the spectral data that is based on Krein's accelerant method.Comment: 39 pages, uses iopart.cls, iopams.sty and setstack.sty by IO
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