Environmental risks for children oral health in Low Danube region

The study was aimed to assess the environmental risks for children oral health in Low Danube region.Material and methods. The study was conducted in 2011-2021. Information on the state of drinking water, the level of environmental safety of food, qualitative and quantitative composition of food was obtained from the reports of territorial institutions of the sanitary-epidemiological service of Odessa region. Actual nutrition was assessed using standard questionnaires. The assessment of the level of environmental and hygienic safety was based on the recommendations of the EPA. Statistical processing was performed by methods of analysis of variance and correlation using specialized software Statistica 10.0.Results. Excessive carbohydrate intake and excessive nitrate load are the main environmental risk factors for dental pathology in children living in the Danube region. Qualitative composition of diets plays a bigger role than mineral composition of drinking water.Conclusion. 1. Drinking water of suboptimal mineral composition was consumed by 41.7% of people, high content of refined carbohydrates was inherent in the diets of 63.0% of surveyed children.2. Children’s diet is characterized with subdeficiency of B vitamins, excessive consumption of refined carbohydrates and a significant nitrate load

Stringiness of Hyaluronic Acid Emulsions

In this work, we underline the importance of the molecular weight of hyaluronic acid on the elongational properties of concentrated emulsions. The filament formation properties, e.g. the stringiness, of an emulsion is a key determinant of a product liking and repeat purchase. Here, we find that high molecular weight hyaluronic acid and a high stretching speed are the control parameters affecting the filament formation of an emulsion.Comment: 15 pages, 4 figures. Published in International Journal of Cosmetic Science, 202

Екологічні детермінанти стану стоматологічного здоров’я дитячого населення Українського Придунав’я

It is well known that the dental health of children determines the health of adults, and is an integral indicator of the overall well-being of society. World experience shows that in the application of modern technologies of primary and secondary prevention, the prevalence of many dental diseases can be significantly reduced. The aim of the study – to determine the environmental determinants for the state of dental health of children of the Ukrainian Danube region (on the example of Izmail district) Materials and Methods. The study was performed at the Department of Pediatric Dentistry, Institute of Dentistry NAMN of Ukraine during 2017–2019. 300 children of both sexes aged 7, 12 and 15 who were living in the settlements of Izmail district were surveyed. The analysis of the level of environmental and hygienic safety in the places of residence of the examined Results and Discussion. It has been shown that was condukted over the past 10 years there has been a tendency towards an increase in the incidence of caries and gingivitis among prepubertal children and adolescents. Among 6-year-old children, there were higher levels of caries and periodontal pathology among young men – CPVz – (0.23±0.1) points, CPVP – (0.23±0.1), RMA – (87.4±4.9) %. These differences are more striking in relation to the condition of dentition teeth: for girls – (3.8±1.0), for boys – (4.8±0.3) points, PPC – (2.8±0.2) and (5.7±0.3) points respectively. A similar pattern is observed in adolescents 12 years old. In boys of this age, the KPUz indicator was (2.6±0.3), and in girls (1.8±0.2) points, KPUP – (3.2±0.3) and (2.1±0.2) points, respectively. Regarding the RMA index, it was (98.9±1.0) % among girls, and (104.3±1.8) % among boys. With age, the differences leveled. It requires an explanation why, in adolescent girls, the level of CPU reached (4.5±0.3) years, and in boys only (2.0±0.2) years. In terms of CPVP, this indicator was (2.2±0.2) years in 15-year-old girls, and (5.3±0.4) in boys (p <0.01). The prevalence of gingivitis was high among boys – (103.0±2.7) % (versus (17.3±0.9) % in girls). Drinking water of non-optimal mineral composition was consumed by 41.7 % of individuals, a high content of refined carbohydrates was inherent in the diets of 63.0 % of the examined children. Conclusion. The ecological determinants of the dental health of the children's population of the Ukrainian Danube are the use of physiologically non-optimal drinking water and the predominance of refined carbohydrates in the diet. The adverse effect of environmental factors on the dental health of the children's population is aggravated with age.Общеизвестно, что стоматологическое здоровье детей определяет здоровье взрослых, и является интегральным показателем общего благополучия общества. Мировой опыт свидетельствует, что в условиях применения современных технологий первичной и вторичной профилактики распространенность многих стоматологических заболеваний может быть существенно уменьшена. Цель исследования – определить экологические детерминанты состояния стоматологического здоровья детского населения Украинского Придунавья (на примере Измаильского района). Материалы и методы. Исследование выполнено на базе отдела детской стоматологии ГУ «Институт стоматологии НАМН Украины» в течении 2017–2019 гг. Было обследовано 300 детей обоего пола в возрасте 7; 12 и 15 лет, проживавших в населенных пунктах Измаильского района. Проведен анализ уровня эколого-гигиенической безопасности в местах проживания обследованных. Результаты исследований и их обсуждение. Показано, что в течение последних10 лет сохраняется тенденция к росту частоты кариеса и гингивита среди детей препубертатного возраста и подростков. Среди 6-летних детей отмечались более высокие уровни распространенности кариеса и патологии пародонта среди юношей – КПВз – (0,23±0,1) балла, КПВп – (0,23±0,1), РМА – (87,4±4,9) %. Более яркими выглядят эти различия относительно состояния зубов сменного прикуса: у девочек КПз – (3,8±1,0), у мальчиков – (4,8±0,3) балла, КПп – соответственно (2,8±0,2) и (5,7±0,3) балла. Подобная картина наблюдается и у подростков 12 лет. У мальчиков этого возраста показатель КПУз составил (2,6±0,3), а у девочек – (1,8±0,2) балла, КПУп – соответственно (3,2±0,3) и (2,1±0,2) балла. Относительно показателя РМА, то он среди девушек составлял (98,9±1,0) %, а среди юношей – (104,3±1,8) %. С возрастом различия нивелировались. Требует объяснения, почему у девушек-подростков уровень КПУз достигал (4,5±0,3) лет, а у мальчиков – только (2,0±0,2) лет. По КПВп, то этот показатель составил в 15-летних девушек (2,2±0,2) лет, а у мальчиков – (5,3±0,4) (p<0,01). Распространение гингивита было большим среди мальчиков – (103,0±2,7) % (против (17,3±0,9) % у девочек). Питьевые воды неоптимального минерального состава потребляли 41,7 % лиц, высокое содержание рафинированных углеводов был присущ рационам 63,0 % обследованных детей. Выводы. К экологическим детерминантам состояния стоматологического здоровья детского населения Украинского Придунавья принадлежат употребление физиологически неоптимальных питьевых вод и преобладание в рационе питания рафинированных углеводов. Неблагоприятное влияние экологических факторов на стоматологическое здоровье детского населения усиливается с возрастом.Загальновідомо, що стоматологічне здоров'я дітей визначає здоров'я дорослих, і є інтегральним показником загального благополуччя суспільства. Світовий досвід свідчить, що за умов застосування сучасних технологій первинної та вторинної профілактики поширеність багатьох стоматологічних захворювань може бути суттєво зменшена. Мета дослідження – визначити екологічні детермінанти стану стоматологічного здоров’я дитячого населення Українського Придунав’я (на прикладі Ізмаїльського району). Матеріали і методи. Дослідження виконано на базі відділу дитячої стоматології ДУ «Інститут стоматології НАМН України» протягом 2017–2019 рр. Було обстежено 300 дітей обох статей у віці 7; 12 та 15 років, які проживали у населених пунктах Ізмаїльського району. Проведено аналіз рівня еколого-гігієнічної безпеки у місцях проживання обстежених. Результати досліджень та їх обговорення. Показано, що упродовж останніх 10 років зберігається тенденція до зростання частоти карієсу та гінгівітів серед дітей препубертатного віку та підлітків. Серед 6-річних дітей відзначалися більш високі рівні поширеності карієсу та патології пародонта серед хлопців – КПВз – (0,23±0,1) бала, КПВп – (0,23±0,1), РМА – (87,4±4,9)  %. Більш яскравими виглядають ці відмінності щодо стану зубів змінного прикусу: в дівчаток КПз – (3,8±1,0), у хлопців – (4,8±0,3) бала, КПп – відповідно (2,8±0,2) й (5,7±0,3) бала. Подібна картина спостерігається й у підлітків 12 років. У хлопців цього віку показник КПВз склав (2,6±0,3), а у дівчат – (1,8±0,2) бала, КПВп – відповідно (3,2±0,3) та (2,1±0,2) бала. Щодо показника РМА, то він серед дівчат складав (98,9±1,0) %, а серед хлопців – (104,3±1,8) %. З віком гендерні відмінності нівелювалися. Потребує пояснення, чому у дівчат-підлітків рівень КПВз сягав (4,5±0,3) року, а у хлопців – лише (2,0±0,2) року. Щодо КПВп, то цей показник склав у 15-річних дівчат – (2,2±0,2) року, а в хлопців – (5,3±0,4) (p<0,01). Поширення гінгівіту було більшим серед хлопців – (103,0±2,7) % (проти (17,3±0,9) % у дівчат). Питні води неоптимального мінерального складу споживали 41,7 % осіб, високий вміст рафінованих вуглеводів був притаманний раціонам 63,0 % обстежених дітей. Висновки. До екологічних детермінант стану стоматологічного здоров’я дитячого населення Українського Придунав’я належать вживання фізіологічно неоптимальних питних вод та переважання у раціоні харчування рафінованих вуглеводів. Несприятливий вплив екологічних чинників на стоматологічне здоров'я дитячого населення посилюється з віком

Photonic crystals of coated metallic spheres

It is shown that simple face-centered-cubic (fcc) structures of both metallic and coated metallic spheres are ideal candidates to achieve a tunable complete photonic bandgap (CPBG) for optical wavelengths using currently available experimental techniques. For coated microspheres with the coating width to plasma wavelength ratio $l_c/\lambda_p \leq 10$ and the coating and host refractive indices $n_c$ and $n_h$, respectively, between 1 and 1.47, one can always find a sphere radius $r_s$ such that the relative gap width $g_w$ (gap width to the midgap frequency ratio) is larger than 5% and, in some cases, $g_w$ can exceed 9%. Using different coatings and supporting liquids, the width and midgap frequency of a CPBG can be tuned considerably.Comment: 14 pages, plain latex, 3 ps figures, to appear in Europhys. Lett. For more info on this subject see http://www.amolf.nl/research/photonic_materials_theory/moroz/moroz.htm

Interacting Growth Walk - a model for hyperquenched homopolymer glass?

We show that the compact self avoiding walk configurations, kinetically generated by the recently introduced Interacting Growth Walk (IGW) model, can be considered as members of a canonical ensemble if they are assigned random values of energy. Such a mapping is necessary for studying the thermodynamic behaviour of this system. We have presented the specific heat data for the IGW, obtained from extensive simulations on a square lattice; we observe a broad hump in the specific heat above the $\theta$-point, contrary to expectation.Comment: 4 figures; Submitted to PR

Metallo-dielectric diamond and zinc-blende photonic crystals

It is shown that small inclusions of a low absorbing metal can have a dramatic effect on the photonic band structure. In the case of diamond and zinc-blende photonic crystals, several complete photonic band gaps (CPBG's) can open in the spectrum, between the 2nd-3rd, 5th-6th, and 8th-9th bands. Unlike in the purely dielectric case, in the presence of small inclusions of a low absorbing metal the largest CPBG for a moderate dielectric constant (epsilon<=10) turns out to be the 2nd-3rd CPBG. The 2nd-3rd CPBG is the most important CPBG, because it is the most stable against disorder. For a diamond and zinc-blende structure of nonoverlapping dielectric and metallo-dielectric spheres, a CPBG begins to decrease with an increasing dielectric contrast roughly at the point where another CPBG starts to open--a kind of gap competition. A CPBG can even shrink to zero when the dielectric contrast increases further. Metal inclusions have the biggest effect for the dielectric constant 2<=epsilon<=12, which is a typical dielectric constant at near infrared and in the visible for many materials, including semiconductors and polymers. It is shown that one can create a sizeable and robust 2nd-3rd CPBG at near infrared and visible wavelengths even for a photonic crystal which is composed of more than 97% low refractive index materials (n<=1.45, i.e., that of silica glass or a polymer). These findings open the door for any semiconductor and polymer material to be used as genuine building blocks for the creation of photonic crystals with a CPBG and significantly increase the possibilities for experimentalists to realize a sizeable and robust CPBG in the near infrared and in the visible. One possibility is a construction method using optical tweezers, which is analyzed here.Comment: 25 pp, 23 figs, RevTex, to appear in Phys Rev B. For more information look at http://www.amolf.nl/research/photonic_materials_theory/moroz/moroz.htm

Origin of the short-range, strong repulsive force between ionic surfactant layers

We study the electrostatic interaction between two ionic surfactant layers by performing molecular dynamic simulations of salt-free thin water films coated by surfactants (Newton black films). We find a strong exponentially decaying short-range repulsion not explained by classical Poisson-Boltzmann theory. This electrostatic force is shown to be mainly due to the anomalous dielectric response of water near charged surfactant layers. This result clarifies the much debated physical mechanism underlying the controversial "hydration forces" observed in experiments. In the case of ionic thin films, the "hydration forces" can be identified with the electrostatic forces induced by the layers of highly polarized water originated at the interfaces

Gradient Optics of subwavelength nanofilms

Propagation and tunneling of light through subwavelength photonic barriers, formed by dielectric layers with continuous spatial variations of dielectric susceptibility across the film are considered. Effects of giant heterogeneity-induced non-local dispersion, both normal and anomalous, are examined by means of a series of exact analytical solutions of Maxwell equations for gradient media. Generalized Fresnel formulae, visualizing a profound influence of gradient and curvature of dielectric susceptibility profiles on reflectance/transmittance of periodical photonic heterostructures are presented. Depending on the cutoff frequency of the barrier, governed by technologically managed spatial profile of its refractive index, propagation or tunneling of light through these barriers are examined. Nonattenuative transfer of EM energy by evanescent waves, tunneling through dielectric gradient barriers, characterized by real values of refractive index, decreasing in the depth of medium, is shown. Scaling of the obtained results for different spectral ranges of visible, IR and THz waves is illustrated. Potential of gradient optical structures for design of miniaturized filters, polarizers and frequency-selective interfaces of subwavelength thickness is considered

Direct Observation of the Dynamics of Latex Particles Confined inside Thinning Water-Air Films

The dynamics of micrometer-size polystyrene latex particles confined in thinning foam films was investigated by microscopic interferometric observation. The behavior of the entrapped particles depends on the mobility of the film surfaces, the particle concentration, hydrophobicity, and rate of film formation. When the films were stabilized by sodium dodecyl sulfate, no entrapment of particles between the surfaces was possible. When protein was used as a stabilizer, a limited number of particles were caught inside the film area due to the decreased mobility of the interfaces. In this case, extraordinary long-ranged (>100 Ìm) capillary attraction leads to two-dimensional (2D) particle aggregation. A major change occurs when the microspheres are partially hydrophobized by the presence of cationic surfactant. After the foam films are opened and closed a few times, a layer of particles simultaneously adsorbed to the two interfaces is formed, which sterically inhibits any further film opening and thinning. The particles within this layer show an excellent 2D hexagonal ordering. The experimental data are relevant to the dynamics of defects in coating films, Pickering emulsions, and particle assembly into 2D arrays