Parametric Modeling as a Technology of Rapid Prototyping in Light Industry

The paper deals with the parametric modeling method of virtual mannequins for the purposes of design automation in clothing industry. The described approach includes the steps of generation of the basic model on the ground of the initial one (obtained in 3D-scanning process), its parameterization and deformation. The complex surfaces are presented by the wireframe model. The modeling results are evaluated with the set of similarity factors. Deformed models are compared with their virtual prototypes. The results of modeling are estimated by the standard deviation factor

Temperature measurement and stabilization in a birefringent whispering gallery resonator

Temperature measurement with nano-Kelvin resolution is demonstrated at room temperature, based on the thermal dependence of an optical crystal anisotropy in a high quality whispering gallery resonator. As the resonator's TE and TM modes frequencies have different temperature coefficients, their differential shift provides a sensitive measurement of the temperature variation, which is used for active stabilization of the temperature

Parametric Modeling as a Technology of Rapid Prototyping in Light Industry

The paper deals with the parametric modeling method of virtual mannequins for the purposes of design automation in clothing industry. The described approach includes the steps of generation of the basic model on the ground of the initial one (obtained in 3D-scanning process), its parameterization and deformation. The complex surfaces are presented by the wireframe model. The modeling results are evaluated with the set of similarity factors. Deformed models are compared with their virtual prototypes. The results of modeling are estimated by the standard deviation factor

Giant optical anisotropy in transition metal dichalcogenides for next-generation photonics

Large optical anisotropy observed in a broad spectral range is of paramount importance for efficient light manipulation in countless devices. Although a giant anisotropy was recently observed in the mid-infrared wavelength range, for visible and near-infrared spectral intervals, the problem remains acute with the highest reported birefringence values of 0.8 in BaTiS3 and h-BN crystals. This inspired an intensive search for giant optical anisotropy among natural and artificial materials. Here, we demonstrate that layered transition metal dichalcogenides (TMDCs) provide an answer to this quest owing to their fundamental differences between intralayer strong covalent bonding and weak interlayer van der Walls interaction. To do this, we carried out a correlative far- and near-field characterization validated by first-principle calculations that reveals an unprecedented birefringence of 1.5 in the infrared and 3 in the visible light for MoS2. Our findings demonstrate that this outstanding anisotropy allows for tackling the diffraction limit enabling an avenue for on-chip next-generation photonics.Comment: 20 pages, 5 figure

Ex vivo перфузия донорских легких с использованием разработанного раствора с последующей ортотопичеcкой левосторонней трансплантацией легкого (экспериментальное исследование)

The continued unavailability of adequate organs for transplantation to meet the existing demand has resulted in a major challenge in transplantology. This is especially felt in lung transplantation (LTx). LTx is the only effective method of treatment for patients with end-stage lung diseases. Normothermic ex vivo lung perfusion (EVLP) has been proposed to increase the number of donor organs suitable for transplant – EVLP has proven itself in a number of clinical trials. The ability to restore suboptimal donor lungs, previously considered unsuitable for transplantation, can improve organ functionality, and thus increase the number of lung transplants. However, widespread implementation of ex vivo perfusion is associated with high financial costs for consumables and perfusate.Objective: to test the developed solution on an ex vivo lung perfusion model, followed by orthotopic LT under experimental conditions.Materials and methods. The experiment included lung explantation stages, static hypothermic storage, EVLP and orthotopic left LTx. Perfusion was performed in a closed perfusion system. We used our own made human albumin-based perfusion solution as perfusate. Perfusion lasted for 2 hours, and evaluation was carried out every 30 minutes. In all cases, static hypothermic storage after perfusion lasted for 4 hours. The orthotopic single-lung transplantation procedure was performed using assisted circulation, supplemented by membrane oxygenation. Postoperative follow-up was 2 hours, after which the experimental animal was euthanized.Results. Respiratory index before lung explantation was 310 ± 40 mmHg. The PaO2/FiO2 ratio had positive growth dynamics throughout the entire EVLP procedure. Oxygenation index was 437 ± 25 mm Hg after 120 minutes of perfusion. Throughout the entire EVLP procedure, there was a steady decrease in pulmonary vascular resistance (PVR). Initial PVR was 300 ± 100 dyn×s/cm5; throughout the EVLP, PVR tended to fall, reaching 38,5 ± 12 dyn×s/cm5 at the end of perfusion.Conclusion. A safe and effective EVLP using our perfusate is possible. The developed orthotopic left lung transplantation protocol under circulatory support conditions, supplemented by membrane oxygenation, showed it is efficient and reliable.На сегодняшний день в трансплантологии дефицит донорских органов остается главной проблемой. Особенно это ощущается в трансплантации легких. Трансплантация легких является единственным эффективным методом лечения пациентов с терминальными стадиями респираторной недостаточности. С целью расширения пула эффективных доноров предлагается технология нормотермической ex vivo перфузии, хорошо зарекомендовавшей себя в ряде клинических исследований. Возможность восстанавливать субоптимальные донорские легкие, считавшиеся ранее не пригодными для трансплантации, позволяет улучшить функциональные возможности органа и тем самым увеличить число трансплантаций легких. Однако широкое внедрение технологии ex vivo перфузии сопряжено с высокими финансовыми затратами на расходные материалы и перфузионный раствор.Цель: апробировать разработанный раствор на модели ex vivo перфузии донорских легких с последующей ортотопической трансплантацией легкого в условиях эксперимента.Материалы и методы. Эксперимент включал стадии эксплантации легких, статическое гипотермическое хранение, процедуру нормотермической ex vivo перфузии и ортотопическую левостороннюю трансплантацию. Перфузия проводилась в замкнутом контуре. В качестве перфузата использовали собственный перфузионный раствор на основе альбумина человека. Время перфузии составляло 2 часа, оценка проводилась каждые 30 минут. Период статического гипотермического хранения после перфузии составил 4 часа во всех наблюдениях. Процедуру ортотопической однолегочной трансплантации выполняли с применением вспомогательного кровообращения, дополненного мембранной оксигенацией. Период наблюдения в послеоперационном периоде составлял 2 часа, после чего проводилась эвтаназия экспериментального животного.Результаты. Показатель респираторного индекса до момента эксплантации донорских легких составлял 310 ± 40 мм рт. ст. На протяжении всей процедуры ex vivo перфузии отмечалась положительная динамика роста PaО2/FiO2. Спустя 120 минут перфузии индекс оксигенации составил 437 ± 25 мм рт. ст. Исходно показатель легочного сосудистого сопротивления (ЛСС) составлял 300 ± 100 Дин×с/см5, на протяжении всей ex vivo перфузии прослеживалась динамика к снижению показателя ЛСС; на окончание перфузии показатель ЛСС составил 38,5 ± 12 Дин×с/см5.Заключение. Экспериментальное исследование показало возможность проведения безопасной и эффективной процедуры нормотермической ex vivo перфузии с использованием отечественного перфузионного раствора. Разработанный протокол ортотопической трансплантации левого легкого в условиях вспомогательного кровообращения, дополненного мембранной оксигенацией, показал свою эффективность и надежность

Changes in the antigenic and genetic structure of influenza viruses: analysis of surveillance data of influenza A and B in Russia in 2006-2013

The goal of this research project was to study the natural variability of human influenza A and B viruses based on the analysis of the population structure of influenza viruses, circulating in Russia in 2006-2013, in order to determine the direction of their genetic and antigenic drift by comparison to the WHO reference strains. Our results proved that during that period significant changes occurred in the genetic structure of influenza viruses, their phylogenetic affiliation, as well as their sensitivity to antiviral drugs. According to the surveillance data, the percentage of influenza A(H1N1) viruses among patients with influenza-like illness or acute respiratory infection gradually decreased from 42% of the total number of influenza viruses in 2006-2007 to 19% in 2008- 2009. Influenza A(H1N1) viruses are characterized by «silent» variability that manifests in the gradual accumulation of amino acid substitutions in the minor undetectable group of viruses.The share of influenza A(H3N2) viruses varied from 10% in the 1st post pandemic year to approx. 60% in 2008-2009 and 2011- 2012 epidemic seasons. All of the influenza A strains isolated during the last years of the period, covered in this study, were found to be susceptible to neuraminidase inhibitors and resistant to adamantane antivirals.Influenza B viruses of both Yamagata and Victoria lineages circulated in Russia in the period from 2006 to 2013. The vast majority of these influenza B viruses belonged to the Victoria lineage. Phylogenetic and antigenic analyses of influenza B viruses have demonstrated a gradual drift of Russian isolates from the reference strains. No changes leading to resistance to oseltamivir or zanamivir were found in influenza B strains isolated until 2013.The goal of this research project was to study the natural variability of human influenza A and B viruses based on the analysis of the population structure of influenza viruses, circulating in Russia in 2006-2013, in order to determine the direction of their genetic and antigenic drift by comparison to the WHO reference strains. Our results proved that during that period significant changes occurred in the genetic structure of influenza viruses, their phylogenetic affiliation, as well as their sensitivity to antiviral drugs. According to the surveillance data, the percentage of influenza A(H1N1) viruses among patients with influenza-like illness or acute respiratory infection gradually decreased from 42% of the total number of influenza viruses in 2006-2007 to 19% in 2008- 2009. Influenza A(H1N1) viruses are characterized by «silent» variability that manifests in the gradual accumulation of amino acid substitutions in the minor undetectable group of viruses. The share of influenza A(H3N2) viruses varied from 10% in the 1st post pandemic year to approx. 60% in 2008-2009 and 2011- 2012 epidemic seasons. All of the influenza A strains isolated during the last years of the period, covered in this study, were found to be susceptible to neuraminidase inhibitors and resistant to adamantane antivirals. Influenza B viruses of both Yamagata and Victoria lineages circulated in Russia in the period from 2006 to 2013. The vast majority of these influenza B viruses belonged to the Victoria lineage. Phylogenetic and antigenic analyses of influenza B viruses have demonstrated a gradual drift of Russian isolates from the reference strains. No changes leading to resistance to oseltamivir or zanamivir were found in influenza B strains isolated until 2013

Searching for Exoplanets Using a Microresonator Astrocomb

Detection of weak radial velocity shifts of host stars induced by orbiting planets is an important technique for discovering and characterizing planets beyond our solar system. Optical frequency combs enable calibration of stellar radial velocity shifts at levels required for detection of Earth analogs. A new chip-based device, the Kerr soliton microcomb, has properties ideal for ubiquitous application outside the lab and even in future space-borne instruments. Moreover, microcomb spectra are ideally suited for astronomical spectrograph calibration and eliminate filtering steps required by conventional mode-locked-laser frequency combs. Here, for the calibration of astronomical spectrographs, we demonstrate an atomic/molecular line-referenced, near-infrared soliton microcomb. Efforts to search for the known exoplanet HD 187123b were conducted at the Keck-II telescope as a first in-the-field demonstration of microcombs

High-frequency acousto-optic effects in Bragg reflectors

Picosecond acoustic interferometry was used to study the acousto-optic properties of a distributed Bragg reflector (DBR) manufactured from two immiscible polymers (cellulose acetate and polyvinylcarbyzole). Picosecond strain pulses were injected into the structure and changes in its reflectance were monitored as a function of time. The reflectance exhibited single-frequency harmonic oscillations as the strain pulse traversed the DBR. A transfer matrix method was used to model the reflectance of the DBR in response to interface modulation and photo-elastic effects. This work shows that photo-elastic effects can account for the acousto-optic response of DBRs with acoustically matched layers