МАТЕМАТИЧЕСКАЯ МОДЕЛЬ ЭЛАСТОМЕРНОГО ПОГЛОЩАЮЩЕГО АППАРАТА

When transporting hazardous liquid cargo by rail a need arises not only for immediate protection of people and infrastructure, but also for preventive measures relating to structural, technical features of tank wagons. At the same time improving reliability and safety of vehicles, according to the author, can be realized by the calculated model for damping devices and, in particular, elastomeric coupler draft gear. The objective of the author is to present a mathematical model of an elastomeric draft gear. To do this, the author uses simulation method, analysis, mathematical methods.An issue of traffic safety of tanks is considered. A mathematical model is developed, describing operation of elastomeric draft gear. This model is a dependence of device reaction and deformation rate, taking into account initial straining of a device and properties of working medium. Mathematical model allows for simulation of elastomeric draft gear operation at any options of shunting collision and transient modes of train motion.При перевозке по железной дороге опасных жидких грузов возникает потребность не только в непосредственной защите людей и инфраструктуры, но и в предупреждающих мерах, которые касаются конструкционных, технических особенностей вагонов-цистерн. При этом повысить надежность и безопасность перевозочных средств, по версии автора, поможет расчетная модель для демфирующих устройств и, в частности, эластомерного поглощающего аппарата автосцепки.Рассматривается вопрос обеспечения безопасности движения цистерн. Разработана математическая модель, описывающая работу эластомерного поглощающего аппарата. Данная модель представляет собой зависимость реакции аппарата от его деформации и скорости деформации, с учетом начальной затяжки аппарата и свойств рабочего тела. Она позволяет рассчитать ситуацию при любых вариантах маневрового соударения и переходных режимах движения поезда

МЕТОДОЛОГИЯ ИССЛЕДОВАНИЯ ИСТОРИИ ТРАНСПОРТНОЙ ТЕХНИКИ

The article reveals methodological approaches to the study of history of production and cars machinery. The basic concepts of production and transport machinery, machines and tools, as well as the principles and methods of the study of history are described. Particular attention is paid to the periodization of historical and technical processes and experiences in applying chronological and chronological-problematic principles. In addition, the authors consider logical method, historical method, mathematization and modeling method. A generalized principle of links-substitution for periodization of technology development processes is offered. A new category is introduced – the level of intelligence of automatic machines, the method of its quantitative assessment is mentioned.Статья раскрывает методологические подходы к исследованию истории техники. Изложены основные понятия производственной и транспортной техники, машин и механизмов, а также принципы и методы изучения исторических явлений и фактов. Особое внимание уделено периодизации историко-технических процессов, опыту применения хронологического и хронологическо-проблемного принципов. Кроме того, рассмотрены логический метод, исторический метод, метод математизации и метод моделирования. Предложен обобщенный принцип звенности-замещения для периодизации процессов развития техники. Введена новая категория – уровень интеллектуальности автоматических машин, назван способ его количественной оценки

О нагруженности котла цистерны при гидроударе

A mathematical model of shunting collision of a tank car is offered, taking into account the possibility of installing automatic couplers with absorbing devices of various types, fluctuations of transported liquid cargo in tank shell at incomplete filling and the likelihood of hydraulic impact. Calculations resulted in proposed choice of rational parameters and of a shape of tank shell bottom which allow increasing carrying load and volume of the tank shell. Scientifically sound limits for impact speed were determined for certain types of shunting operations with tanks to ensure safe working conditions, minimization of environmental risks.Предложена математическая модель маневрового соударения вагонацистерны, учитывающая возможность установки автосцепных устройств с поглощающими аппаратами различных типов, колебания перевозимого жидкого груза в котле при неполном наливе и вероятность появления гидроудара. Расчетным путем подобраны рациональные параметры и форма днища котла цистерны, которые позволяют увеличить ее грузоподъёмность и объем котла. Определены научно обоснованные ограничения для скоростей соударения при некоторых видах маневровых операций с цистернами для обеспечения безопасных условий, минимизации экологических рисков

Cryo-TEM micrographs of PLDTS (a) and PLD (b) liposomal formulations at 25°C.

<p>Clearly seen are the ellipsoid liposomes containing the loaded doxorubicin, similar to what was previously observed for doxorubicin-loaded liposomes (Doxil/Myocet) <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092555#pone.0092555-Barenholz1" target="_blank">[8]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092555#pone.0092555-Lasic2" target="_blank">[23]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092555#pone.0092555-Swenson1" target="_blank">[62]</a>.</p

Therapeutic Efficacy of Combining PEGylated Liposomal Doxorubicin and Radiofrequency (RF) Ablation: Comparison between Slow-Drug-Releasing, Non-Thermosensitive and Fast-Drug-Releasing, Thermosensitive Nano-Liposomes

<div><p>Aims</p><p>To determine how the accumulation of drug in mice bearing an extra-hepatic tumor and its therapeutic efficacy are affected by the type of PEGylated liposomal doxorubicin used, treatment modality, and rate of drug release from the liposomes, when combined with radiofrequency (RF) ablation.</p><p>Materials and Methods</p><p>Two nano-drugs, both long-circulating PEGylated doxorubicin liposomes, were formulated: (1) PEGylated doxorubicin in thermosensitive liposomes (PLDTS), having a burst-type fast drug release above the liposomes’ solid ordered to liquid disordered phase transition (at 42°C), and (2) non-thermosensitive PEGylated doxorubicin liposomes (PLDs), having a slow and continuous drug release. Both were administered intravenously at 8 mg/kg doxorubicin dose to tumor-bearing mice. Animals were divided into 6 groups: no treatment, PLD, RF, RF+PLD, PLDTS, and PLDTS+RF, for intra-tumor doxorubicin deposition at 1, 24, and 72 h post-injection (in total 41, mice), and 31 mice were used for randomized survival studies.</p><p>Results</p><p>Non-thermosensitive PLD combined with RF had the least tumor growth and the best end-point survival, better than PLDTS+RF (p<0.005) or all individual therapies (p<0.001). Although at 1 h post-treatment the greatest amount of intra-tumoral doxorubicin was seen following PLDTS+RF (p<0.05), by 24 and 72 h the greatest doxorubicin amount was seen for PLD+RF (p<0.05); in this group the tumor also has the longest exposure to doxorubicin.</p><p>Conclusion</p><p>Optimizing therapeutic efficacy of PLD requires a better understanding of the relationship between the effect of RF on tumor microenvironment and liposome drug release profile. If drug release is too fast, the benefit of changing the microenvironment by RF on tumor drug localization and therapeutic efficacy may be much smaller than for PLDs having slow and temperature-independent drug release. Thus the much longer circulation time of doxorubicin from PLD than from PLDTS may be beneficial in many therapeutic instances, especially in extra-hepatic tumors.</p></div

Automated Analysis of X-Ray Images of the Temporomandibular Joint in Patients with Orthognathic Bite and Physiological Occlusion

Objective: to propose a procedure for analyzing the X-ray image of the temporomandibular joint (TMJ) through the automated calculation of linear and angular measurements from craniometry points in comparison with the reference values.Material and methods. Fifty TMJ cone beam computed tomography images were analyzed in 25 volunteers aged 18-25 years with orthognathic bite and physiological occlusion. All the tomography images were analyzed from craniometric points, by using a section corresponding to the midsagittal plane of the TMJ. Angular and linear measurements characterizing the functional capacities of the TMJ were determined. A statistical analysis involved descriptive methods and was carried out by the IBM SPSS 21 statistics.Results. The introduction of automated estimation of TMJ functional capacities from angular and linear measurements made it possible to obtain the following data: the α-angle was 11.99±2.44° for the right TMJ and 12.12±2.78° for the left one; the β-angle was 11.58±2.31° for the right TMJ and 12.42±2.81° for the left one; the γ-angle was 156.41±4.57° for the right TMJ and 155.46±5.50° for the left one. A descriptive statistics checking revealed no gross errors.Conclusion. It is expedient to take into account the findings as reference values to characterize the anatomical and functional state of the TMJ on the x-ray image

Mice tumor model therapeutic efficacy studies using PLD and PLDTS with and without RF ablation.

<p>(a) Effect of the various treatments on tumor volume during 90 days duration, and (b) survival of mice by using surrogate end point.</p

Liposome characterization.

<p>*No phase transition is explained by the high mole % of cholesterol.</p