There are applications of the finite difference time domain (FDTD) method, which need to model thin wires in dispersive media. However, existing thin wire techniques in the FDTD method are developed only for the conductive and dielectric media. The article presents a modification of oblique thin wire formalism proposed by Guiffaut et al. and a minor modification for the technique proposed by Railton et al. for applications with Debye media. The modifications are based on auxiliary differential equation (ADE) method. The modifications are validated by calculations of grounding potential rise (GPR) of a horizontal electrode buried in soil with dispersive properties.

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Recent studies show that the frequency dependent soil properties can significantly influence transient grounding resistance and, subsequently, lightning protection and reliability of the electrical grid. However, these properties require further research: for example, it is not clear what factors (apart from the low-frequency resistivity) should be taken into consideration to determine accurately the properties for a particular soil (without conducting laborious measurements). Additional experimental data are needed.When measurements are conducted, the electromagnetic coupling between circuits can cause significant measurement error at frequencies about several MHz. In order to estimate this error, it is convenient to use a calculation method, as in this case, it is possible to set particular frequency dependent properties for the ground and compare those with the calculated ones (using an electrode array).In the article, the electromagnetic coupling error is examined for several commonly used electrode arrays using the finite difference time domain method. This method allows simulating wires with infinite length, which is important for modeling pole-dipole and pole-pole arrays. Its drawback for this type of calculations, however, that it is relatively time-consuming. It was found that among the considered array configurations the error is smallest for the dipole-dipole arrays with the perpendicular allocation of the measurement wires and the pole-dipole array. By increasing the distance between particular parts of measurement wires, one can significantly reduce the error for some other arrays.

Objective. To assess the efficacy of postoperative continuous intralesional analgesia in patients with tuberculous spondylitis. Material and Methods. Patients (n = 56) with tuberculous spondylitis undergoing radical reconstructive spinal surgery were randomized into two groups depending on the type of post-operative analgesia: standard parenteral analgesia in Group I, and continuous intralesional infusion with local anesthetic in Group II. The amount of administered narcotic and non-narcotic analgesics was evaluated with formalized Analgesic Assessment Scale, postoperative activity -with the Patient Activity Scale, and pain intensity -with the VAS. Side effects of analgesic therapy were registered. Results. Statistical analysis revealed reliable differences in terms of the assessed analgesic amounts, VAS indexes and frequency of side effects between groups. Results in Group I were reliably higher than in Group II. Цель исследования. Оценка эффективности после-операционного обезболивания методом продленной внутрираневой анальгезии у больных туберкулезным спондилитом. Материал и методы. Пациенты (n = 56) с туберкулез-ным спондилитом, перенесшие радикально-реконструк-тивные операции на позвоночнике, путем рандомизации распределены в две группы по характеру послеопера-ционного обезболивания: в первой группе применяли стандартное парентеральное введение анальгетических препаратов, во второй-продленное внутрираневое вве-дение местного анестетика. Объем использованных нар-котических и ненаркотических анальгетиков определяли по формализированной шкале анальгетиков, послеопе-рационную активность -по шкале активности пациен-тов, выраженность болевого синдрома -по ВАШ. Фик-сировали побочные эффекты анальгетической терапии. Результаты. При статистическом анализе в группах вы-явлены достоверные различия оценок по формализован-ной шкале анальгетиков и ВАШ, а также по частоте по-бочных эффектов. В первой группе результаты оказались достоверно больше, чем во второй. Заключение. Исследование демонстрирует эффектив-ность и безопасность применения продленного обезбо-ливания раны инфузией 0,2 % ропивакаина через специ-альный катетер в раннем послеоперационном периоде. Ключевые слова: послеоперационная боль, послеопера-ционное обезболивание, туберкулезный спондилит, ре-конструктивные операции на позвоночнике, продленная анестезия послеоперационной раны.

Existing approaches for the field measurements of the frequency-dependent soil properties take a significant amount of time, making it difficult to obtain new experimental data and study the electrical soil properties further. However, a relatively uncomplicated measurement device assembled from accessible electronic components can make the measurements almost as easy as those for the regular low-frequency resistivity. This article presents a detailed description of such a device: the description includes the functional scheme, pseudocodes for central parts of the calculation algorithm, used electronic components, and working principle of the device. This article discusses the reasons behind the chosen parameters of the device (such as isolation between the measurement circuits, generated signal waveform, and usage of the electrode arrays) and addresses other possible approaches for the measurements. This paper also provides several measurement results and a comparison with a calculation result for a particular electrode array configuration. Finally, this work describes essential aspects affecting the accuracy of measurement results.