A Dynamical Model of Optimal Allocation of Resources to R&D

We provide steps towards a welfare analysis of a two-country endogenous growth model where a relatively small follower absorbs part of the knowledge generated in the leading country. To solve a suitably defined dynamic optimization problem an appropriate version of the Pontryagin maximum principle is developed. The properties of optimal controls and the corresponding optimal trajectories are characterized by the qualitative analysis of the solutions of the Hamiltonian system arising through the implementation of the Pontryagin maximum principle. We find that for a quite small follower, optimization produces the same asymptotic rate of innovation as the market. However, relative knowledge stocks and levels of productivity differ, in general. Thus, policy intervention has no effect on growth rates but may also affect these relative levels. The results are different for not so small follower economies. The present paper provides the rigorous justification for the results presented in Aseev, Hutschenreiter and Kryazhimskii, 2002

Optimal Investment in R&D with International Knowledge Spillovers

We provide steps towards a welfare analysis of a two-country endogenous growth model where a relatively small follower absorbs part of the knowledge generated in the leading country. To solve a suitably defined infinite-horizon dynamic optimization problem a specialized version of the Pontryagin maximum principle had to be applied. For a quite small follower, optimization produces the same asymptotic rate of innovation as the market. However, relative knowledge stocks and levels of productivity differ in the two solutions. Thus, optimal policy intervention has no effect on long-run growth rates but affects these relative levels

Reduction in ionic permeability of a silicone hydrogel contact lenses after one month of daily wear

[EN] Purpose. To compare the ionic permeability using the ionoflux method of new and worn samples of a silicone hydrogel contact lens material. Methods. An ionoflux experimental setup was established to measure the ionic permeability (NaCl) of soft contact lenses. Samples of a silicone hydrogel lens (Comfilcon A, Coopervision, Pleasanton, CA) with optical powers of -1.00, -1.50 and -4.75 diopters (D) were used in this study. Three samples of each power were measured after being worn for one month on a daily wear basis. Lenses were cleaned and disinfected every night using multipurpose disinfecting solutions. Three samples of new lenses from the same batch and the same optical power were also measured to evaluate the effect of lens wear on the ionic permeability of the lens material. Before measurement, the lenses were equilibrated with a 1 M NaCl solution during one week before of each measurement. Results. Lens power had minimal effect on the ionic permeability of a modern silicone hydrogel contact lens with the -1.00 lens having a 15% lower permeability compared to the other two lenses. After one month of lens wear the apparent ionic permeability for lenses with -1.50 D decreased by 15%. In the case of -1.00 and -4.75 D lenses there was a decrease of 26%. Conclusions. The ionic permeability of silicone hydrogel lenses of different optical powers was not significantly different. Worn lenses present a significant reduction of the ionic permeability after a month of wear. The potential effect this reduction on lens movement and discomfort associated to lens wear should be further evaluated.The authors have no proprietary interest in any of the materials mentioned in this article. This work was funded in part by FEDER through the COMPTETE Program and by the Portuguese Foundation for Science and Technology (FCT) in the framework of projects PTDC/SAU-BEB/098391/2008, PTDC/SAU-BEB/098392/2008 and the Strategic Project PEST-C/FIS/UI607/2011.Ferreira Da Silva, AR.; Compañ Moreno, V.; Gonzalez-Meijome, JM. (2015). Reduction in ionic permeability of a silicone hydrogel contact lenses after one month of daily wear. Materials Research Express. 2(6). https://doi.org/10.1088/2053-1591/2/6/065007S26Yoon, S. C., & Jhon, M. S. (1982). The transport phenomena of some model solutes through postcrosslinked poly(2-hydroxyethyl methacrylate) membranes with different tactic precursors. Journal of Applied Polymer Science, 27(8), 3133-3149. doi:10.1002/app.1982.070270834Yasuda, H., Lamaze, C. E., & Ikenberry, L. D. (1968). Die Makromolekulare Chemie, 118(1), 19-35. doi:10.1002/macp.1968.021180102MURPHY, S., HAMILTON, C., & TIGHE, B. (1988). Synthetic hydrogels: 5. Transport processes in 2-hydroxyethyl methacrylate copolymers. Polymer, 29(10), 1887-1893. doi:10.1016/0032-3861(88)90407-7Nicolson, P. C., & Vogt, J. (2001). Soft contact lens polymers: an evolution. Biomaterials, 22(24), 3273-3283. doi:10.1016/s0142-9612(01)00165-xMonticelli, M. V., Chauhan, A., & Radke, C. J. (2005). The Effect of Water Hydraulic Permeability on the Settling of a Soft Contact Lens on the Eye. Current Eye Research, 30(5), 329-336. doi:10.1080/02713680590934085Guan, L., Jiménez, M. E. G., Walowski, C., Boushehri, A., Prausnitz, J. M., & Radke, C. J. (2011). Permeability and partition coefficient of aqueous sodium chloride in soft contact lenses. Journal of Applied Polymer Science, 122(3), 1457-1471. doi:10.1002/app.33336Cheng, M.-L., & Sun, Y.-M. (2005). Observation of the solute transport in the permeation through hydrogel membranes by using FTIR-microscopy. Journal of Membrane Science, 253(1-2), 191-198. doi:10.1016/j.memsci.2005.01.017CHHABRA, M., PRAUSNITZ, J., & RADKE, C. (2007). A single-lens polarographic measurement of oxygen permeability (Dk) for hypertransmissible soft contact lenses. Biomaterials, 28(30), 4331-4342. doi:10.1016/j.biomaterials.2007.06.024González-Méijome, J. M., López-Alemany, A., Almeida, J. B., & Parafita, M. A. (2009). Surface AFM microscopy of unworn and worn samples of silicone hydrogel contact lenses. Journal of Biomedical Materials Research Part B: Applied Biomaterials, 88B(1), 75-82. doi:10.1002/jbm.b.31153González-Méijome, J. M., López-Alemany, A., Almeida, J. B., & Parafita, M. A. (2008). Dynamic in vitro dehydration patterns of unworn and worn silicone hydrogel contact lenses. Journal of Biomedical Materials Research Part B: Applied Biomaterials, 90B(1), 250-258. doi:10.1002/jbm.b.31279Pozuelo, J., Compañ, V., González-Méijome, J. M., González, M., & Mollá, S. (2014). Oxygen and ionic transport in hydrogel and silicone-hydrogel contact lens materials: An experimental and theoretical study. Journal of Membrane Science, 452, 62-72. doi:10.1016/j.memsci.2013.10.010Wolffsohn, J. S., Hunt, O. A., & Basra, A. K. (2009). Simplified recording of soft contact lens fit. Contact Lens and Anterior Eye, 32(1), 37-42. doi:10.1016/j.clae.2008.12.00

Phenomenology of Quantum Gravity and its Possible Role in Neutrino Anomalies

New phenomenological models of Quantum Gravity have suggested that a Lorentz-Invariant discrete spacetime structure may become manifest through a nonstandard coupling of matter fields and spacetime curvature. On the other hand, there is strong experimental evidence suggesting that neutrino oscillations cannot be described by simply considering neutrinos as massive particles. In this manuscript we motivate and construct one particular phenomenological model of Quantum Gravity that could account for the so-called neutrino anomalies.Comment: For the proceedings of "Relativity and Gravitation: 100 Years after Einstein in Prague" (June 2012, Prague

Sonochemical Oxidation of Bisphenol A Under of High-Frequency Ultrasound

Изучены закономерности деструкции Бисфенола А (БФА) в водных растворах при воздействии акустической кавитации 1,7 МГц (УЗ), в Фентон-подобной железо-персульфатной системе и в комбинированной системе . Доказано, что высокочастотный ультразвук мегагерцового диапазона по сравнению с низкочастотным является более энергоэффективным для осуществления сонохимических реакций. Установлено, что скорость реакции окисления БФА возрастает в ряду: . Показано, что в комбинированной окислительной системе наблюдается полная деструкция таргетного соединения, при этом минерализация общего органического углерода достигает 30 %The paper presents the results of investigations on the use of high-frequency ultrasonic cavitation of 1.7 MHz (US), in the Fenton-like iron-persulfate system and in the combined system for destruction Bisphenol A (BPA) in aqueous solutions. The studies revealed that the most effective treatment process involves high-frequency ultrasound in the megahertz range, compared to low-frequency ultrasound, is more energy efficient for sonochemical reactions. The results of this research revealed that the rate of the BPA oxidation reaction increases in the series: . The oxidative system, complete destruction of the target compound is observed, while the mineralization of total organic carbon reaches 30

Photochemical Destruction of Methyl Orange Azo Dye in a Combined Iron-Persulfate System

Изучены закономерности окислительной деструкции биорезистентных органических соединений, на примере азокрасителя метилового оранжевого (МО), в инициированных естественным солнечным излучением окислительных системах. По степени превращения МО и эффективности обесцвечивания раствора рассмотренные окислительные системы можно выстроить в ряд: {Fe0/S2O8 2-/Solar}>{S2O8 2-/Solar}>{Fe0/S2O8 2-}>{Solar}. Установлено, что лишь в Solar-индуцированной Фентон-подобной окислительной системе {Fe0/S2O8 2-/Solar} происходит не только полное превращение МО, но и его минерализация (43–72 %). В реальной водной матрице (в природной поверхностной воде р.Селенга) наблюдается ингибирование окислительных процессов, что обусловлено преимущественно влиянием гидрокарбонатов. Полученные результаты свидетельствуют о перспективности использования окислительной системы {Fe0/S2O8 2-/Solar} при разработке инновационных технологий глубокой очистки сточных вод, содержащих биорезистентные органические соединенияRegularities of oxidative degradation of bioresistant organic compounds were studied, using the methyl orange azo dye (MO) as the target, in oxidative systems initiated by natural solar irradiation. According to the conversion degree of MO and the efficiency of solution discoloration, the considered oxidative systems can be arranged in the following order: {Fe0/S2O82-/Solar}>{S2O82-/Solar}>{Fe0/S2O82-}>{Solar}. It has been established that only in the Solar-induced Fenton- like oxidative system {Fe0/S2O82-/Solar}, not only complete conversion of the MO occurs, but also its mineralization (43–72 %). In a real water matrix (in the natural surface water of the Selenga River), inhibition of oxidative processes is observed, which is mainly due to the influence of hydrocarbonates. The obtained results indicate the prospects of using the oxidative system {Fe0/S2O82-/Solar} in the development of innovative technologies for deep treatment of wastewater containing bioresistant organic compound

IN MEMORY OF ARKADY VIKTOROVICH KRYAZHIMSKIY (1949–2014)

The article is devoted to the description of Academician Arkady Kryazhimskiy's life path. The facts of the scientific biography of Acad. Kryazhimskiy are presented with the emphasis on his outstanding contribution into the theory of dynamic inversion, the theory of differential games, and control theory. His personal talents in different spheres are also marked out

IN MEMORY OF ARKADY VIKTOROVICH KRYAZHIMSKIY (1949–2014)

The article is devoted to the description of Academician Arkady Kryazhimskiy's life path. The facts of the scientific biography of Acad. Kryazhimskiy are presented with the emphasis on his outstanding contribution into the theory of dynamic inversion, the theory of differential games, and control theory. His personal talents in different spheres are also marked out