360 research outputs found

    Association of Plasma Total Cysteine and Anthropometric Status in 6–30 Months Old Indian Children

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    High-quality protein has been associated with child growth; however, the role of the amino acid cysteine remains unclear. The aim was to measure the extent to which plasma total cysteine (tCys) concentration is associated with anthropometric status in children aged 6–30 months living in New Delhi, India. The study was a prospective cohort study including 2102 children. We calculated Z-scores for height-for-age (HAZ), weight-for-height (WHZ), or weight-for-age (WAZ) according to the WHO Child Growth Standards. We used multiple regression models to estimate the association between tCys and the anthropometric indices. A high proportion of the children were categorized as malnourished at enrolment; 41% were stunted (HAZ ≀ βˆ’2), 19% were wasted (WHZ ≀ βˆ’2) and 42% underweight (WAZ ≀ βˆ’2). Plasma total cysteine (tCys) was significantly associated with HAZ, WHZ and WAZ after adjusting for relevant confounders (p 25th percentile. In young Indian children from low-to-middle socioeconomic neighborhoods, a low plasma total cysteine concentration was associated with an increased risk of poor anthropometric status.publishedVersio

    Be-10 age constraints on latest Pleistocene and Holocene cirque glaciation across the western United States

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    Paleoclimate: A rocky reworking of Holocene glaciology New dating of glacially-deposited rocks substantially revises our understanding of the waxing and waning of ice since the last glacial maximum. Glaciologists have long thought that moraines throughout the western United States represent β€˜neoglacial’ advances about 6,000 years ago. Now, a multi-institution team led by Shaun Marcott at the University of Wisconsin-Madison has found β€” using cosmogenic isotopes β€” that these terminal deposits left by advancing glaciers are instead 9,000 to 15,000 years old. The research advances prior work by using absolute, not relative ages, and documents that glaciers retreated after the last glacial maximum ~ 21,000 years ago, fluctuated locally throughout much of the Holocene, and re-advanced during the Little Ice Age of a few hundred years ago. Glacial advances that might have occurred during the neoglacial were wiped away by the more extensive glaciations of the Little Ice Age

    Dynamics investigation in the Venus upper atmosphere

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    The O_2 nightglow emissions in the infrared spectral range are important features to investigate dynamics at the mesospheric altitudes, in the planetary atmosphere. In this work, we analyzed the profiles obtained at limb by the VIRTIS spectrometer on board the Venus Express mission, acquired during the mission period from 2006-07-05 to 2008-08-15 to investigate possible gravity waves characteristics at the airglow altitudes. Indeed, several profiles present double peaked structures that can be interpreted as due to gravity waves. In analogy to the Earth's and Mars cases, we use a well-known theory to model the O_2 nightglow emissions affected by gravity waves propagation, in order to support this thesis and derive the waves properties. We discuss results from 30 profiles showing double peaked structures, focusing on vertical wavelength and wave amplitude of the possible gravity waves. On average, the double peaked profiles are compatible with the effects of gravity waves with a vertical wavelength ranging between 7 and 16 km, and wave amplitude of 3-14%. A comparison with gravity waves properties in the Mars and Earth's atmospheres, using the same theory, is also proposed \citep{altieri_2014}. \ The research is supported by ASI (contract ASI-INAF I/050/10/0)

    Foveoschisis prediction based analysis of macular retina OCT-scan. Part II. Prediction of microcavity growth in retinal foveoschisis

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    Π—Π°Π·Π½Π°Ρ‡Π΅Π½ΠΎ, Ρ‰ΠΎ Ρƒ Ρ…ΠΎΠ΄Ρ– дослідТСння Ρƒ всіх ΠΏΠ°Ρ†Ρ–Ρ”Π½Ρ‚Ρ–Π² Π· високою осьовою ΠΌΡ–ΠΎΠΏΡ–Ρ”ΡŽ Π½Π° сканограммах виявлСно Π½Π°ΡΠ²Π½Ρ–ΡΡ‚ΡŒ ΠΌΡ–ΠΎΠΏΡ–Ρ‡Π½ΠΎΠ³ΠΎ ΠΏΡ€ΠΎΡ„Ρ–Π»ΡŽ заднього полюса ΠΎΠΊΠ°, ΠΎΠ±ΡƒΠΌΠΎΠ²Π»Π΅Π½Ρƒ задньою ΡΡ‚Π°Ρ„Ρ–Π»ΠΎΠΌΠΎΡŽ, Ρ‚Π° Π·ΠΌΡ–Π½ΠΈ Ρ€Π΅Π»ΡŒΡ”Ρ„Ρƒ ΠΉ Π°Ρ€Ρ…Ρ–Ρ‚Π΅ΠΊΡ‚ΠΎΠ½Ρ–ΠΊΠΈ сітківки Π² ділянці ΠΌΠ°ΠΊΡƒΠ»ΠΈ. Π£ Π·ΠΎΠ²Π½Ρ–ΡˆΠ½Ρ–Ρ… ΡˆΠ°Ρ€Π°Ρ… сітківки Ρƒ Ρ€Π°Π·Ρ– Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΡƒ визначалися Π³Ρ–ΠΏΠΎΠ΅Ρ…ΠΎΠ³Π΅Π½Π½Ρ– ΠΌΡ–ΠΊΡ€ΠΎΠΏΠΎΡ€ΠΎΠΆΠ½ΠΈΠ½ΠΈ Ρ€Ρ–Π·Π½ΠΎΠ³ΠΎ Ρ€ΠΎΠ·ΠΌΡ–Ρ€Ρƒ. ΠœΠΎΠΆΠ»ΠΈΠ²Ρ– ΠΏΡ€ΠΈΡ‡ΠΈΠ½ΠΈ появи Ρ‚Π° подальшого прогрСсування Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΡƒ ΠΌΠΎΠΆΠ½Π° Ρ€ΠΎΠ·Π΄Ρ–Π»ΠΈΡ‚ΠΈ Π½Π° Скстра- Ρ‚Π° Ρ–Π½Ρ‚Ρ€Π°Ρ€Π΅Ρ‚ΠΈΠ½Π°Π»ΡŒΠ½Ρ–. Π”ΠΎ Π΅ΠΊΡΡ‚Ρ€Π°Ρ€Π΅Ρ‚ΠΈΠ½Π°Π»ΡŒΠ½ΠΈΡ… ΠΏΡ€ΠΈΡ‡ΠΈΠ½ слід віднСсти Π½Π°ΡΠ²Π½Ρ–ΡΡ‚ΡŒ Π²Ρ–Ρ‚Ρ€Π΅ΠΎΡ€Π΅Ρ‚ΠΈΠ½Π°Π»ΡŒΠ½ΠΈΡ… Ρ‚Ρ€Π°ΠΊΡ†Ρ–ΠΉ Ρ– Π·Π°Π΄Π½ΡŒΠΎΡ— ΠΌΡ–ΠΎΠΏΡ–Ρ‡Π½ΠΎΡ— стафіломи. Π”ΠΎ Ρ–Π½Ρ‚Ρ€Π°Ρ€Π΅Ρ‚ΠΈΠ½Π°Π»ΡŒΠ½ΠΈΡ… - появу ΠΌΡ–ΠΊΡ€ΠΎΠΏΠΎΡ€ Π² Π·ΠΎΠ²Π½Ρ–ΡˆΠ½ΡŒΠΎΠΌΡƒ сітчастому ΡˆΠ°Ρ€Ρ– сітківки. ΠŸΡ–Π΄ час опису процСсів, Ρ‰ΠΎ Π²Ρ–Π΄Π±ΡƒΠ²Π°ΡŽΡ‚ΡŒΡΡ Ρƒ Ρ€Π°Π·Ρ– Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΡƒ, застосовано Ρ„Ρ–Π·ΠΈΡ‡Π½Ρ– Π·Π°ΠΊΠΎΠ½ΠΈ, Ρ‰ΠΎ ΠΎΠΏΠΈΡΡƒΡŽΡ‚ΡŒ Π΄Π΅Ρ„ΠΎΡ€ΠΌΠ°Ρ†Ρ–Ρ— Ρ‚Π° руйнування, які Π²Ρ–Π΄Π±ΡƒΠ²Π°ΡŽΡ‚ΡŒΡΡ Π² ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡ‚Π½ΠΈΡ… ΠΌΠ°Ρ‚Π΅Ρ€Ρ–Π°Π»Π°Ρ…. ΠΠ°ΡΠ²Π½Ρ–ΡΡ‚ΡŒ ΠΌΡ–ΠΊΡ€ΠΎΠΏΠΎΡ€ Π² Ρ‚ΠΊΠ°Π½ΠΈΠ½Ρ– сітківки Ρƒ Ρ€Π°Π·Ρ– Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΡƒ ΠΏΡ€ΠΈΠ·Π²ΠΎΠ΄ΠΈΡ‚ΡŒ Π΄ΠΎ ΠΊΠΎΠ½Ρ†Π΅Π½Ρ‚Ρ€Π°Ρ†Ρ–Ρ— Π·Π½Π°Ρ‡Π½ΠΈΡ… ΠΌΠ΅Ρ…Π°Π½Ρ–Ρ‡Π½ΠΈΡ… Π½Π°ΠΏΡ€ΡƒΠΆΠ΅Π½ΡŒ, які Ρ‚ΠΈΠΌ Ρ–ΡΡ‚ΠΎΡ‚Π½Ρ–ΡˆΠ΅ Π±ΡƒΠ΄ΡƒΡ‚ΡŒ позначатися Π½Π° пруТнопластичних властивостях сітківки, Ρ‡ΠΈΠΌ Π²ΠΈΡ‰Π΅ Ρ—Ρ… концСнтрація. ΠžΠ±Π³ΠΎΠ²ΠΎΡ€Π΅Π½ΠΎ ΠΏΡ€ΠΈΡ€ΠΎΠ΄Ρƒ зростання ΠΌΠ΅Ρ…Π°Π½Ρ–Ρ‡Π½ΠΈΡ… Π½Π°ΠΏΡ€ΡƒΠΆΠ΅Π½ΡŒ Π² сітківці Ρƒ Ρ€Π°Π·Ρ– Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΡƒ. НавСдСний Π°Π½Π°Π»Ρ–Π· ΠΌΠΎΠΆΠ΅ лягти Π² основу визначСння пластичних Π΅Ρ„Π΅ΠΊΡ‚Ρ–Π² Π½Π°Π²ΠΊΠΎΠ»ΠΎ ΠΌΡ–ΠΊΡ€ΠΎΠΏΠΎΡ€, Ρ‰ΠΎ Π½Π°Π΄Π°Π»Ρ– Π΄ΠΎΠ·Π²ΠΎΠ»ΠΈΡ‚ΡŒ ΡΡ„ΠΎΡ€ΠΌΡƒΠ»ΡŽΠ²Π°Ρ‚ΠΈ ΠΊΠΎΠ½ΠΊΡ€Π΅Ρ‚Π½Ρ– ΠΊΡ–Π»ΡŒΠΊΡ–ΡΠ½Ρ– ΠΊΡ€ΠΈΡ‚Π΅Ρ€Ρ–Ρ— зростання ΠΌΡ–ΠΊΡ€ΠΎΠΏΠΎΡ€ΠΎΠΆΠ½ΠΈΠ½ Ρƒ Ρ€Π°Π·Ρ– Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΡƒ Π·Π° Π·Π°Π΄Π°Π½ΠΈΡ… Π·ΠΎΠ²Π½Ρ–ΡˆΠ½Ρ–Ρ… ΡƒΠΌΠΎΠ².ΠžΡ‚ΠΌΠ΅Ρ‡Π΅Π½ΠΎ, Ρ‡Ρ‚ΠΎ Π² Ρ…ΠΎΠ΄Π΅ исслСдования Ρƒ всСх ΠΏΠ°Ρ†ΠΈΠ΅Π½Ρ‚ΠΎΠ² с высокой осСвой ΠΌΠΈΠΎΠΏΠΈΠ΅ΠΉ Π½Π° сканограммах выявлСно Π½Π°Π»ΠΈΡ‡ΠΈΠ΅ миопичСского профиля Π·Π°Π΄Π½Π΅Π³ΠΎ полюса Π³Π»Π°Π·Π°, обусловлСнноС Π·Π°Π΄Π½Π΅ΠΉ стафиломой, ΠΈ измСнСния Ρ€Π΅Π»ΡŒΠ΅Ρ„Π° ΠΈ Π°Ρ€Ρ…ΠΈΡ‚Π΅ΠΊΡ‚ΠΎΠ½ΠΈΠΊΠΈ сСтчатки Π² области ΠΌΠ°ΠΊΡƒΠ»Ρ‹. Π’ΠΎ Π²Π½Π΅ΡˆΠ½ΠΈΡ… слоях сСтчатки ΠΏΡ€ΠΈ Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΠ΅ ΠΎΠΏΡ€Π΅Π΄Π΅Π»ΡΠ»ΠΈΡΡŒ гипоэхогСнныС микрополости Ρ€Π°Π·Π½ΠΎΠ³ΠΎ Ρ€Π°Π·ΠΌΠ΅Ρ€Π°. Π’ΠΎΠ·ΠΌΠΎΠΆΠ½Ρ‹Π΅ ΠΏΡ€ΠΈΡ‡ΠΈΠ½Ρ‹ появлСния ΠΈ дальнСйшСго прогрСсса Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΠ° ΠΌΠΎΠΆΠ½ΠΎ Ρ€Π°Π·Π΄Π΅Π»ΠΈΡ‚ΡŒ Π½Π° экстра- ΠΈ ΠΈΠ½Ρ‚Ρ€Π°Ρ€Π΅Ρ‚ΠΈΠ½Π°Π»ΡŒΠ½Ρ‹Π΅. К ΡΠΊΡΡ‚Ρ€Π°Ρ€Π΅Ρ‚ΠΈΠ½Π°Π»ΡŒΠ½Ρ‹ΠΌ ΠΏΡ€ΠΈΡ‡ΠΈΠ½Π°ΠΌ слСдуСт отнСсти Π½Π°Π»ΠΈΡ‡ΠΈΠ΅ Π²ΠΈΡ‚Ρ€Π΅ΠΎΡ€Π΅Ρ‚ΠΈΠ½Π°Π»ΡŒΠ½Ρ‹Ρ… Ρ‚Ρ€Π°ΠΊΡ†ΠΈΠΉ ΠΈ Π·Π°Π΄Π½Π΅ΠΉ миопичСской стафиломы. К ΠΈΠ½Ρ‚Ρ€Π°Ρ€Π΅Ρ‚ΠΈΠ½Π°Π»ΡŒΠ½Ρ‹ΠΌ - появлСниС ΠΌΠΈΠΊΡ€ΠΎΠΏΠΎΡ€ Π²ΠΎ внСшнСм сСтчатом слоС сСтчатки. ΠŸΡ€ΠΈ описании процСссов, ΠΊΠΎΡ‚ΠΎΡ€Ρ‹Π΅ происходят ΠΏΡ€ΠΈ Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΠ΅, Π±Ρ‹Π»ΠΈ ΠΏΡ€ΠΈΠΌΠ΅Π½Π΅Π½Ρ‹ физичСскиС Π·Π°ΠΊΠΎΠ½Ρ‹, ΠΊΠΎΡ‚ΠΎΡ€Ρ‹Π΅ ΠΎΠΏΠΈΡΡ‹Π²Π°ΡŽΡ‚ Π΄Π΅Ρ„ΠΎΡ€ΠΌΠ°Ρ†ΠΈΠΈ ΠΈ Ρ€Π°Π·Ρ€ΡƒΡˆΠ΅Π½ΠΈΡ, ΠΊΠΎΡ‚ΠΎΡ€Ρ‹Π΅ происходят Π² ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡ‚Π½Ρ‹Ρ… ΠΌΠ°Ρ‚Π΅Ρ€ΠΈΠ°Π»Π°Ρ…. НаличиС ΠΌΠΈΠΊΡ€ΠΎΠΏΠΎΡ€ Π² Ρ‚ΠΊΠ°Π½ΠΈ сСтчатки ΠΏΡ€ΠΈ Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΠ΅ ΠΏΡ€ΠΈΠ²ΠΎΠ΄ΠΈΡ‚ ΠΊ ΠΊΠΎΠ½Ρ†Π΅Π½Ρ‚Ρ€Π°Ρ†ΠΈΠΈ Π·Π½Π°Ρ‡ΠΈΡ‚Π΅Π»ΡŒΠ½Ρ‹Ρ… мСханичСских напряТСний, ΠΊΠΎΡ‚ΠΎΡ€Ρ‹Π΅ Ρ‚Π΅ΠΌ сущСствСннСС Π±ΡƒΠ΄ΡƒΡ‚ ΠΎΡ‚Ρ€Π°ΠΆΠ°Ρ‚ΡŒΡΡ Π½Π° пруТнопластичных свойствах сСтчатки, Ρ‡Π΅ΠΌ Π²Ρ‹ΡˆΠ΅ ΠΈΡ… концСнтрация. ΠžΠ±ΡΡƒΠΆΠ΄Π΅Π½Π° ΠΏΡ€ΠΈΡ€ΠΎΠ΄Π° роста мСханичСских напряТСний Π² сСтчаткС ΠΏΡ€ΠΈ Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΠ΅. ΠŸΡ€ΠΈΠ²Π΅Π΄Π΅Π½Π½Ρ‹ΠΉ Π°Π½Π°Π»ΠΈΠ· ΠΌΠΎΠΆΠ΅Ρ‚ Π»Π΅Ρ‡ΡŒ Π² основу опрСдСлСния пластичных эффСктов Π²ΠΎΠΊΡ€ΡƒΠ³ ΠΌΠΈΠΊΡ€ΠΎΠΏΠΎΡ€, Ρ‡Ρ‚ΠΎ Π² дальнСйшСм ΠΏΠΎΠ·Π²ΠΎΠ»ΠΈΡ‚ ΡΡ„ΠΎΡ€ΠΌΡƒΠ»ΠΈΡ€ΠΎΠ²Π°Ρ‚ΡŒ ΠΊΠΎΠ½ΠΊΡ€Π΅Ρ‚Π½Ρ‹Π΅ количСствСнныС ΠΊΡ€ΠΈΡ‚Π΅Ρ€ΠΈΠΈ роста микрополостСй ΠΏΡ€ΠΈ Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΠ΅ ΠΏΡ€ΠΈ Π·Π°Π΄Π°Π½Π½Ρ‹Ρ… Π²Π½Π΅ΡˆΠ½ΠΈΡ… условиях.ΠžΠ΄Π΅Ρ€ΠΆΠ°Π½ΠΎ ΠΊΡ–Π»ΡŒΠΊΡ–ΡΠ½Ρ– ΠΊΡ€ΠΈΡ‚Π΅Ρ€Ρ–Ρ— прогнозування Ρ€ΠΎΠ·Π²ΠΈΡ‚ΠΊΡƒ Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΡƒ Π·Π° високої ΠΎΡΡŒΠΎΠ²ΠΎΡ— ΠΌΡ–ΠΎΠΏΡ–Ρ— Π½Π° основі ΡΠ΅Ρ€Π΅Π΄Π½ΡŒΠΎΡ— ΠΊΠΎΠ½Ρ†Π΅Π½Ρ‚Ρ€Π°Ρ†Ρ–Ρ— ΠΌΡ–ΠΊΡ€ΠΎΠΏΠΎΡ€ΠΎΠΆΠ½ΠΈΠ½ Π² ΠΎΠ±'Ρ”ΠΌΡ– сітківки, Π° Ρ‚Π°ΠΊΠΎΠΆ Π½Π° основі ΠΌΠ΅Ρ‚ΠΎΠ΄Ρƒ балансу Π΅Π½Π΅Ρ€Π³Ρ–Ρ— Π² Ρ€Π°ΠΌΠΊΠ°Ρ… ΠΌΠΎΠ΄Π΅Π»Ρ– Π½Π΅Π»Ρ–Π½Ρ–ΠΉΠ½ΠΎΠ³ΠΎ ΠΏΡ€ΡƒΠΆΠ½ΠΎ-пластичного сСрСдовища. ΠŸΡ€Π°ΠΊΡ‚ΠΈΡ‡Π½Π΅ використання Π·Π½Π°ΠΉΠ΄Π΅Π½ΠΈΡ… ΠΊΡ€ΠΈΡ‚Π΅Ρ€Ρ–Ρ—Π² для ΠΏΡ€ΠΎΠ³Π½ΠΎΠ·Ρƒ прогрСсування Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΠ½ΠΎΠ³ΠΎ Ρ€ΠΎΠ·ΠΌΡ–Ρ€Ρƒ ΠΌΡ–ΠΊΡ€ΠΎΠΏΠΎΡ€ΠΎΠΆΠ½ΠΈΠ½ΠΈ Π² Ρ‚ΠΎΠ²Ρ‰Ρ– сітківки Π·Π° Π΄Π°Π½ΠΈΠΌΠΈ ΡΠΏΠ΅ΠΊΡ‚Ρ€Π°Π»ΡŒΠ½ΠΎΡ— ΠΎΠΏΡ‚ΠΈΡ‡Π½ΠΎΡ— ΠΊΠΎΠ³Π΅Ρ€Π΅Π½Ρ‚Π½ΠΎΡ— Ρ‚ΠΎΠΌΠΎΠ³Ρ€Π°Ρ„Ρ–Ρ—.ΠŸΠΎΠ»ΡƒΡ‡Π΅Π½Ρ‹ количСствСнныС ΠΊΡ€ΠΈΡ‚Π΅Ρ€ΠΈΠΈ прогнозирования развития Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΠ° ΠΏΡ€ΠΈ высокой осСвой ΠΌΠΈΠΎΠΏΠΈΠΈ Π½Π° основС срСднСй ΠΊΠΎΠ½Ρ†Π΅Π½Ρ‚Ρ€Π°Ρ†ΠΈΠΈ микрополостСй Π² объСмС сСтчатки, Π° Ρ‚Π°ΠΊΠΆΠ΅ Π½Π° основС ΠΌΠ΅Ρ‚ΠΎΠ΄Π° баланса энСргии Π² Ρ€Π°ΠΌΠΊΠ°Ρ… ΠΌΠΎΠ΄Π΅Π»ΠΈ Π½Π΅Π»ΠΈΠ½Π΅ΠΉΠ½ΠΎΠΉ ΡƒΠΏΡ€ΡƒΠ³ΠΎ-пластичной срСды. ΠŸΡ€Π°ΠΊΡ‚ΠΈΡ‡Π΅ΡΠΊΠΎΠ΅ использованиС Π½Π°ΠΉΠ΄Π΅Π½Π½Ρ‹Ρ… ΠΊΡ€ΠΈΡ‚Π΅Ρ€ΠΈΠ΅Π² для ΠΏΡ€ΠΎΠ³Π½ΠΎΠ·Π° прогрСсса Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΠ½ΠΎΠ³ΠΎ Ρ€Π°Π·ΠΌΠ΅Ρ€Π° микрополости Π² Π±ΠΎΠ»Π΅Π΅ толстыС сСтчатки ΠΏΠΎ Π΄Π°Π½Π½Ρ‹ΠΌ ΡΠΏΠ΅ΠΊΡ‚Ρ€Π°Π»ΡŒΠ½ΠΎΠΉ оптичСской ΠΊΠΎΠ³Π΅Ρ€Π΅Π½Ρ‚Π½ΠΎΠΉ Ρ‚ΠΎΠΌΠΎΠ³Ρ€Π°Ρ„ΠΈΠΈ.Introduction. Increasing the number and size of microcavities in the retina is an important clinical manifestation of foveoschisis progression. However, there are no data about the patterns change shape and size of microcavities in the retina in the foveoschisis progression. Purpose. To develop quantitative criteria for predicting foveoschisis development in high axial myopia based on the average concentration of microcavities in retinal volume and based on the energy balance in the framework of nonlinear elastic-plastic medium. Material and methods. We examined 7 patients (14 eyes) with high axial myopia and myopic maculopathy. All patients underwent a spectral optical coherence tomography. Mathematical methods in the theory of destruction of elastic and elastic-plastic materials were applied. Results. The quantitative criteria for predicting foveoschisis development in high axial myopia based on the average concentration of microcavities in retinal volume and based on the energy balance in the framework of nonlinear elastic-plastic medium was set. In the first case in the formula for calculating the risk of progression foveoschisis accounted size of the plastic stress at the edge of a void in the retina, the distance between the micro-cavities. In other there is a merge of microcavities and progression foveoschisis. In the second case, the mathematical solution is reduced to the determination of destruction energy disclosure in a continuous medium. This takes into account the Poisson ratio of the retina, the Young’s modulus, the intraocular pressure, the size of a void in the retina, the stress intensity factor in the thickness of the retina. Practical use of the criteria found to predict foveoschisis progression involves determining intraocular pressure and the maximum linear dimension of a void in the thickness of the retina according to the spectral optical coherence tomography. In the calculations, take into account the biophysical properties of the retina

    Challenges and research priorities to understand interactions between climate, ice sheets and global mean sea level during past interglacials

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    Quaternary interglacials provide key observations of the Earth system's responses to orbital and greenhouse gas forcing. They also inform on the capabilities of Earth system models, used for projecting the polar ice-sheet and sea-level responses to a regional warmth comparable to that expected by 2100 C.E. However, a number of uncertainties remain regarding the processes and feedbacks linking climate, ice-sheet and sea-level changes during past warm intervals. Here, we delineate the major research questions that need to be resolved and future research directions that should be taken by the paleoclimate, sea-level and ice-sheet research communities in order to increase confidence in the use of past interglacial climate, ice-sheet and sea-level reconstructions to constrain future predictions. These questions were formulated during a joint workshop held by the PAGES-INQUA PALSEA (PALeo constraints on SEA level rise) and the PAGES-PMIP QUIGS (QUaternary InterGlacialS) Working Groups in September 2018.PAGE

    Foveoschisis prediction based on analysis of macular retina OPT scan. Part 1. Elementary accumulation mechanism of volumetric mechanical stress in the retina

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    Π—Π°Π·Π½Π°Ρ‡Π΅Π½ΠΎ, Ρ‰ΠΎ Ρƒ Ρ…ΠΎΠ΄Ρ– дослідТСння Ρƒ всіх ΠΏΠ°Ρ†Ρ–Ρ”Π½Ρ‚Ρ–Π² Π· високою осьовою ΠΌΡ–ΠΎΠΏΡ–Ρ”ΡŽ Π½Π° сканограммах виявлСно Π½Π°ΡΠ²Π½Ρ–ΡΡ‚ΡŒ ΠΌΡ–ΠΎΠΏΡ–Ρ‡Π½ΠΎΠ³ΠΎ ΠΏΡ€ΠΎΡ„Ρ–Π»ΡŽ заднього полюса ΠΎΠΊΠ°, ΠΎΠ±ΡƒΠΌΠΎΠ²Π»Π΅Π½Ρƒ задньою ΡΡ‚Π°Ρ„Ρ–Π»ΠΎΠΌΠΎΡŽ, Ρ‚Π° Π·ΠΌΡ–Π½ΠΈ Ρ€Π΅Π»ΡŒΡ”Ρ„Ρƒ ΠΉ Π°Ρ€Ρ…Ρ–Ρ‚Π΅ΠΊΡ‚ΠΎΠ½Ρ–ΠΊΠΈ сітківки Π² ділянці ΠΌΠ°ΠΊΡƒΠ»ΠΈ. Π£ Π·ΠΎΠ²Π½Ρ–ΡˆΠ½Ρ–Ρ… ΡˆΠ°Ρ€Π°Ρ… сітківки Ρƒ Ρ€Π°Π·Ρ– Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΡƒ визначалися Π³Ρ–ΠΏΠΎΠ΅Ρ…ΠΎΠ³Π΅Π½Π½Ρ– ΠΌΡ–ΠΊΡ€ΠΎΠΏΠΎΡ€ΠΎΠΆΠ½ΠΈΠ½ΠΈ Ρ€Ρ–Π·Π½ΠΎΠ³ΠΎ Ρ€ΠΎΠ·ΠΌΡ–Ρ€Ρƒ. ΠœΠΎΠΆΠ»ΠΈΠ²Ρ– ΠΏΡ€ΠΈΡ‡ΠΈΠ½ΠΈ появи Ρ‚Π° подальшого прогрСсування Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΡƒ ΠΌΠΎΠΆΠ½Π° Ρ€ΠΎΠ·Π΄Ρ–Π»ΠΈΡ‚ΠΈ Π½Π° Скстра- Ρ‚Π° Ρ–Π½Ρ‚Ρ€Π°Ρ€Π΅Ρ‚ΠΈΠ½Π°Π»ΡŒΠ½Ρ–. Π”ΠΎ Π΅ΠΊΡΡ‚Ρ€Π°Ρ€Π΅Ρ‚ΠΈΠ½Π°Π»ΡŒΠ½ΠΈΡ… ΠΏΡ€ΠΈΡ‡ΠΈΠ½ слід віднСсти Π½Π°ΡΠ²Π½Ρ–ΡΡ‚ΡŒ Π²Ρ–Ρ‚Ρ€Π΅ΠΎΡ€Π΅Ρ‚ΠΈΠ½Π°Π»ΡŒΠ½ΠΈΡ… Ρ‚Ρ€Π°ΠΊΡ†Ρ–ΠΉ Ρ– Π·Π°Π΄Π½ΡŒΠΎΡ— ΠΌΡ–ΠΎΠΏΡ–Ρ‡Π½ΠΎΡ— стафіломи. Π”ΠΎ Ρ–Π½Ρ‚Ρ€Π°Ρ€Π΅Ρ‚ΠΈΠ½Π°Π»ΡŒΠ½ΠΈΡ… - появу ΠΌΡ–ΠΊΡ€ΠΎΠΏΠΎΡ€ Π² Π·ΠΎΠ²Π½Ρ–ΡˆΠ½ΡŒΠΎΠΌΡƒ сітчастому ΡˆΠ°Ρ€Ρ– сітківки. ΠŸΡ–Π΄ час опису процСсів, Ρ‰ΠΎ Π²Ρ–Π΄Π±ΡƒΠ²Π°ΡŽΡ‚ΡŒΡΡ Ρƒ Ρ€Π°Π·Ρ– Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΡƒ, застосовано Ρ„Ρ–Π·ΠΈΡ‡Π½Ρ– Π·Π°ΠΊΠΎΠ½ΠΈ, Ρ‰ΠΎ ΠΎΠΏΠΈΡΡƒΡŽΡ‚ΡŒ Π΄Π΅Ρ„ΠΎΡ€ΠΌΠ°Ρ†Ρ–Ρ— Ρ‚Π° руйнування, які Π²Ρ–Π΄Π±ΡƒΠ²Π°ΡŽΡ‚ΡŒΡΡ Π² ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡ‚Π½ΠΈΡ… ΠΌΠ°Ρ‚Π΅Ρ€Ρ–Π°Π»Π°Ρ…. ΠΠ°ΡΠ²Π½Ρ–ΡΡ‚ΡŒ ΠΌΡ–ΠΊΡ€ΠΎΠΏΠΎΡ€ Π² Ρ‚ΠΊΠ°Π½ΠΈΠ½Ρ– сітківки Ρƒ Ρ€Π°Π·Ρ– Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΡƒ ΠΏΡ€ΠΈΠ·Π²ΠΎΠ΄ΠΈΡ‚ΡŒ Π΄ΠΎ ΠΊΠΎΠ½Ρ†Π΅Π½Ρ‚Ρ€Π°Ρ†Ρ–Ρ— Π·Π½Π°Ρ‡Π½ΠΈΡ… ΠΌΠ΅Ρ…Π°Π½Ρ–Ρ‡Π½ΠΈΡ… Π½Π°ΠΏΡ€ΡƒΠΆΠ΅Π½ΡŒ, які Ρ‚ΠΈΠΌ Ρ–ΡΡ‚ΠΎΡ‚Π½Ρ–ΡˆΠ΅ Π±ΡƒΠ΄ΡƒΡ‚ΡŒ позначатися Π½Π° пруТнопластичних властивостях сітківки, Ρ‡ΠΈΠΌ Π²ΠΈΡ‰Π΅ Ρ—Ρ… концСнтрація. ΠžΠ±Π³ΠΎΠ²ΠΎΡ€Π΅Π½ΠΎ ΠΏΡ€ΠΈΡ€ΠΎΠ΄Ρƒ зростання ΠΌΠ΅Ρ…Π°Π½Ρ–Ρ‡Π½ΠΈΡ… Π½Π°ΠΏΡ€ΡƒΠΆΠ΅Π½ΡŒ Π² сітківці Ρƒ Ρ€Π°Π·Ρ– Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΡƒ. НавСдСний Π°Π½Π°Π»Ρ–Π· ΠΌΠΎΠΆΠ΅ лягти Π² основу визначСння пластичних Π΅Ρ„Π΅ΠΊΡ‚Ρ–Π² Π½Π°Π²ΠΊΠΎΠ»ΠΎ ΠΌΡ–ΠΊΡ€ΠΎΠΏΠΎΡ€, Ρ‰ΠΎ Π½Π°Π΄Π°Π»Ρ– Π΄ΠΎΠ·Π²ΠΎΠ»ΠΈΡ‚ΡŒ ΡΡ„ΠΎΡ€ΠΌΡƒΠ»ΡŽΠ²Π°Ρ‚ΠΈ ΠΊΠΎΠ½ΠΊΡ€Π΅Ρ‚Π½Ρ– ΠΊΡ–Π»ΡŒΠΊΡ–ΡΠ½Ρ– ΠΊΡ€ΠΈΡ‚Π΅Ρ€Ρ–Ρ— зростання ΠΌΡ–ΠΊΡ€ΠΎΠΏΠΎΡ€ΠΎΠΆΠ½ΠΈΠ½ Ρƒ Ρ€Π°Π·Ρ– Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΡƒ Π·Π° Π·Π°Π΄Π°Π½ΠΈΡ… Π·ΠΎΠ²Π½Ρ–ΡˆΠ½Ρ–Ρ… ΡƒΠΌΠΎΠ².ΠžΡ‚ΠΌΠ΅Ρ‡Π΅Π½ΠΎ, Ρ‡Ρ‚ΠΎ Π² Ρ…ΠΎΠ΄Π΅ исслСдования Ρƒ всСх ΠΏΠ°Ρ†ΠΈΠ΅Π½Ρ‚ΠΎΠ² с высокой осСвой ΠΌΠΈΠΎΠΏΠΈΠ΅ΠΉ Π½Π° сканограммах выявлСно Π½Π°Π»ΠΈΡ‡ΠΈΠ΅ миопичСского профиля Π·Π°Π΄Π½Π΅Π³ΠΎ полюса Π³Π»Π°Π·Π°, обусловлСнноС Π·Π°Π΄Π½Π΅ΠΉ стафиломой, ΠΈ измСнСния Ρ€Π΅Π»ΡŒΠ΅Ρ„Π° ΠΈ Π°Ρ€Ρ…ΠΈΡ‚Π΅ΠΊΡ‚ΠΎΠ½ΠΈΠΊΠΈ сСтчатки Π² области ΠΌΠ°ΠΊΡƒΠ»Ρ‹. Π’ΠΎ Π²Π½Π΅ΡˆΠ½ΠΈΡ… слоях сСтчатки ΠΏΡ€ΠΈ Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΠ΅ ΠΎΠΏΡ€Π΅Π΄Π΅Π»ΡΠ»ΠΈΡΡŒ гипоэхогСнныС микрополости Ρ€Π°Π·Π½ΠΎΠ³ΠΎ Ρ€Π°Π·ΠΌΠ΅Ρ€Π°. Π’ΠΎΠ·ΠΌΠΎΠΆΠ½Ρ‹Π΅ ΠΏΡ€ΠΈΡ‡ΠΈΠ½Ρ‹ появлСния ΠΈ дальнСйшСго прогрСсса Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΠ° ΠΌΠΎΠΆΠ½ΠΎ Ρ€Π°Π·Π΄Π΅Π»ΠΈΡ‚ΡŒ Π½Π° экстра- ΠΈ ΠΈΠ½Ρ‚Ρ€Π°Ρ€Π΅Ρ‚ΠΈΠ½Π°Π»ΡŒΠ½Ρ‹Π΅. К ΡΠΊΡΡ‚Ρ€Π°Ρ€Π΅Ρ‚ΠΈΠ½Π°Π»ΡŒΠ½Ρ‹ΠΌ ΠΏΡ€ΠΈΡ‡ΠΈΠ½Π°ΠΌ слСдуСт отнСсти Π½Π°Π»ΠΈΡ‡ΠΈΠ΅ Π²ΠΈΡ‚Ρ€Π΅ΠΎΡ€Π΅Ρ‚ΠΈΠ½Π°Π»ΡŒΠ½Ρ‹Ρ… Ρ‚Ρ€Π°ΠΊΡ†ΠΈΠΉ ΠΈ Π·Π°Π΄Π½Π΅ΠΉ миопичСской стафиломы. К ΠΈΠ½Ρ‚Ρ€Π°Ρ€Π΅Ρ‚ΠΈΠ½Π°Π»ΡŒΠ½Ρ‹ΠΌ - появлСниС ΠΌΠΈΠΊΡ€ΠΎΠΏΠΎΡ€ Π²ΠΎ внСшнСм сСтчатом слоС сСтчатки. ΠŸΡ€ΠΈ описании процСссов, ΠΊΠΎΡ‚ΠΎΡ€Ρ‹Π΅ происходят ΠΏΡ€ΠΈ Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΠ΅, Π±Ρ‹Π»ΠΈ ΠΏΡ€ΠΈΠΌΠ΅Π½Π΅Π½Ρ‹ физичСскиС Π·Π°ΠΊΠΎΠ½Ρ‹, ΠΊΠΎΡ‚ΠΎΡ€Ρ‹Π΅ ΠΎΠΏΠΈΡΡ‹Π²Π°ΡŽΡ‚ Π΄Π΅Ρ„ΠΎΡ€ΠΌΠ°Ρ†ΠΈΠΈ ΠΈ Ρ€Π°Π·Ρ€ΡƒΡˆΠ΅Π½ΠΈΡ, ΠΊΠΎΡ‚ΠΎΡ€Ρ‹Π΅ происходят Π² ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡ‚Π½Ρ‹Ρ… ΠΌΠ°Ρ‚Π΅Ρ€ΠΈΠ°Π»Π°Ρ…. НаличиС ΠΌΠΈΠΊΡ€ΠΎΠΏΠΎΡ€ Π² Ρ‚ΠΊΠ°Π½ΠΈ сСтчатки ΠΏΡ€ΠΈ Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΠ΅ ΠΏΡ€ΠΈΠ²ΠΎΠ΄ΠΈΡ‚ ΠΊ ΠΊΠΎΠ½Ρ†Π΅Π½Ρ‚Ρ€Π°Ρ†ΠΈΠΈ Π·Π½Π°Ρ‡ΠΈΡ‚Π΅Π»ΡŒΠ½Ρ‹Ρ… мСханичСских напряТСний, ΠΊΠΎΡ‚ΠΎΡ€Ρ‹Π΅ Ρ‚Π΅ΠΌ сущСствСннСС Π±ΡƒΠ΄ΡƒΡ‚ ΠΎΡ‚Ρ€Π°ΠΆΠ°Ρ‚ΡŒΡΡ Π½Π° пруТнопластичных свойствах сСтчатки, Ρ‡Π΅ΠΌ Π²Ρ‹ΡˆΠ΅ ΠΈΡ… концСнтрация. ΠžΠ±ΡΡƒΠΆΠ΄Π΅Π½Π° ΠΏΡ€ΠΈΡ€ΠΎΠ΄Π° роста мСханичСских напряТСний Π² сСтчаткС ΠΏΡ€ΠΈ Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΠ΅. ΠŸΡ€ΠΈΠ²Π΅Π΄Π΅Π½Π½Ρ‹ΠΉ Π°Π½Π°Π»ΠΈΠ· ΠΌΠΎΠΆΠ΅Ρ‚ Π»Π΅Ρ‡ΡŒ Π² основу опрСдСлСния пластичных эффСктов Π²ΠΎΠΊΡ€ΡƒΠ³ ΠΌΠΈΠΊΡ€ΠΎΠΏΠΎΡ€, Ρ‡Ρ‚ΠΎ Π² дальнСйшСм ΠΏΠΎΠ·Π²ΠΎΠ»ΠΈΡ‚ ΡΡ„ΠΎΡ€ΠΌΡƒΠ»ΠΈΡ€ΠΎΠ²Π°Ρ‚ΡŒ ΠΊΠΎΠ½ΠΊΡ€Π΅Ρ‚Π½Ρ‹Π΅ количСствСнныС ΠΊΡ€ΠΈΡ‚Π΅Ρ€ΠΈΠΈ роста микрополостСй ΠΏΡ€ΠΈ Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΠ΅ ΠΏΡ€ΠΈ Π·Π°Π΄Π°Π½Π½Ρ‹Ρ… Π²Π½Π΅ΡˆΠ½ΠΈΡ… условиях.ΠžΠ΄Π΅Ρ€ΠΆΠ°Π½ΠΎ ΠΊΡ–Π»ΡŒΠΊΡ–ΡΠ½Ρ– ΠΊΡ€ΠΈΡ‚Π΅Ρ€Ρ–Ρ— прогнозування Ρ€ΠΎΠ·Π²ΠΈΡ‚ΠΊΡƒ Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΡƒ Π·Π° високої ΠΎΡΡŒΠΎΠ²ΠΎΡ— ΠΌΡ–ΠΎΠΏΡ–Ρ— Π½Π° основі ΡΠ΅Ρ€Π΅Π΄Π½ΡŒΠΎΡ— ΠΊΠΎΠ½Ρ†Π΅Π½Ρ‚Ρ€Π°Ρ†Ρ–Ρ— ΠΌΡ–ΠΊΡ€ΠΎΠΏΠΎΡ€ΠΎΠΆΠ½ΠΈΠ½ Π² ΠΎΠ±'Ρ”ΠΌΡ– сітківки, Π° Ρ‚Π°ΠΊΠΎΠΆ Π½Π° основі ΠΌΠ΅Ρ‚ΠΎΠ΄Ρƒ балансу Π΅Π½Π΅Ρ€Π³Ρ–Ρ— Π² Ρ€Π°ΠΌΠΊΠ°Ρ… ΠΌΠΎΠ΄Π΅Π»Ρ– Π½Π΅Π»Ρ–Π½Ρ–ΠΉΠ½ΠΎΠ³ΠΎ ΠΏΡ€ΡƒΠΆΠ½ΠΎ-пластичного сСрСдовища. ΠŸΡ€Π°ΠΊΡ‚ΠΈΡ‡Π½Π΅ використання Π·Π½Π°ΠΉΠ΄Π΅Π½ΠΈΡ… ΠΊΡ€ΠΈΡ‚Π΅Ρ€Ρ–Ρ—Π² для ΠΏΡ€ΠΎΠ³Π½ΠΎΠ·Ρƒ прогрСсування Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΠ½ΠΎΠ³ΠΎ Ρ€ΠΎΠ·ΠΌΡ–Ρ€Ρƒ ΠΌΡ–ΠΊΡ€ΠΎΠΏΠΎΡ€ΠΎΠΆΠ½ΠΈΠ½ΠΈ Π² Ρ‚ΠΎΠ²Ρ‰Ρ– сітківки Π·Π° Π΄Π°Π½ΠΈΠΌΠΈ ΡΠΏΠ΅ΠΊΡ‚Ρ€Π°Π»ΡŒΠ½ΠΎΡ— ΠΎΠΏΡ‚ΠΈΡ‡Π½ΠΎΡ— ΠΊΠΎΠ³Π΅Ρ€Π΅Π½Ρ‚Π½ΠΎΡ— Ρ‚ΠΎΠΌΠΎΠ³Ρ€Π°Ρ„Ρ–Ρ—.ΠŸΠΎΠ»ΡƒΡ‡Π΅Π½Ρ‹ количСствСнныС ΠΊΡ€ΠΈΡ‚Π΅Ρ€ΠΈΠΈ прогнозирования развития Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΠ° ΠΏΡ€ΠΈ высокой осСвой ΠΌΠΈΠΎΠΏΠΈΠΈ Π½Π° основС срСднСй ΠΊΠΎΠ½Ρ†Π΅Π½Ρ‚Ρ€Π°Ρ†ΠΈΠΈ микрополостСй Π² объСмС сСтчатки, Π° Ρ‚Π°ΠΊΠΆΠ΅ Π½Π° основС ΠΌΠ΅Ρ‚ΠΎΠ΄Π° баланса энСргии Π² Ρ€Π°ΠΌΠΊΠ°Ρ… ΠΌΠΎΠ΄Π΅Π»ΠΈ Π½Π΅Π»ΠΈΠ½Π΅ΠΉΠ½ΠΎΠΉ ΡƒΠΏΡ€ΡƒΠ³ΠΎ-пластичной срСды. ΠŸΡ€Π°ΠΊΡ‚ΠΈΡ‡Π΅ΡΠΊΠΎΠ΅ использованиС Π½Π°ΠΉΠ΄Π΅Π½Π½Ρ‹Ρ… ΠΊΡ€ΠΈΡ‚Π΅Ρ€ΠΈΠ΅Π² для ΠΏΡ€ΠΎΠ³Π½ΠΎΠ·Π° прогрСсса Ρ„ΠΎΠ²Π΅ΠΎΡˆΠΈΠ·ΠΈΡΠ½ΠΎΠ³ΠΎ Ρ€Π°Π·ΠΌΠ΅Ρ€Π° микрополости Π² Π±ΠΎΠ»Π΅Π΅ толстыС сСтчатки ΠΏΠΎ Π΄Π°Π½Π½Ρ‹ΠΌ ΡΠΏΠ΅ΠΊΡ‚Ρ€Π°Π»ΡŒΠ½ΠΎΠΉ оптичСской ΠΊΠΎΠ³Π΅Ρ€Π΅Π½Ρ‚Π½ΠΎΠΉ Ρ‚ΠΎΠΌΠΎΠ³Ρ€Π°Ρ„ΠΈΠΈ.Introduction. At present mechanisms of retinal property changes in foveoschisis have not been studied; there is no mathematical model of foveoschisis development. Purpose. To develop a mathematical model of the mechanism of retinal property changes in foveoschisis. Material and methods. We examined 7 patients (14 eyes) with high axial myopia and myopic maculopathy. All patients underwent a spectral optical coherence tomography. Mathematical methods in the theory of destruction of elastic and elastic- plastic materials were applied. Results. There are posterior staphyloma and myopic foveoschisis diagnosed in all patients with high axial myopia. Potential causes of foveoschisis progressing can be divided into extraretinal and intraretinal ones. The extraretinal causes are the presence of vitreoretinal traction and posterior myopic staphyloma. The intraretinal causes are the appearance of micropores in the outer plexiform layer of the retina. In describing the processes occurring during foveoschisis there were applied physical laws describing the deformation and fracture occurring in composite materials. The presence of micropores in the retinal tissue in foveoschisis concentration leads to significant mechanical stress, which will be more substantial impact on the elastoplastic properties of the retina, the higher is their concentration. There was discussed the nature of the increase in stress in the retina in foveoschisis. The above analysis can be the basis excluding the effects of the plastic around the micropores, which will allow to formulate specific quantitative criteria in foveoschisis in future

    ΠžΡΠΎΠ±Π΅Π½Π½ΠΎΡΡ‚ΠΈ синтСза слоТных эфиров пСнтаэритрита ΠΈ алифатичСских ΠΊΠ°Ρ€Π±ΠΎΠ½ΠΎΠ²Ρ‹Ρ… кислот ΠΈΠ·ΠΎΠΌΠ΅Ρ€Π½ΠΎΠ³ΠΎ строСния

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    Objectives. Due to their structures, pentaerythritol esters have a number of appealing properties such as high viscosity index when used as oils and excellent compatibility with polyvinyl chloride when used as plasticizers. For the production of pentaerythritol and carboxylic acids, natural gas can be used as a feedstock, which implies a strategic development of the petrochemical industry, a decrease in the amount of gas used for combustion, and its applications for the production of chemical products.Methods. The synthesis process was conducted in a self-catalysis mode with excess acids in a molar ratio of 8:1 and in the presence of a solvent (toluene) of ~30% per reaction mass. This ensures a uniform distillation of the reaction water at a constant temperature of 100–110 Β°C, a decrease in the side reaction products, and an increase in process selectivity. The products from the reaction mass were isolated by vacuum distillation, and identification of all the synthesized tetraesters was performed by chromatography–mass spectrometry analysis.Results. This work proposes options for optimizing the conditions of the thermal esterification of pentaerythritol with isomeric monocarboxylic acids (isobutyric, isovaleric, pivalic, and 2-ethylhexanoic acids) that have different reactivities due to their structures. Methods for isolating tetraesters of pentaerythritol and corresponding acids have been developed. The characteristics of the main series of ions of tetraesters of pentaerythritol and aliphatic isomeric acids C4–C8 in the mass spectra were obtained.Conclusions. The yields of tetraesters were at 95%–96% of the theoretical value, and product purity was >99.6%. The resulting target products (tetraesters) were characterized by relative color stability, where the maximum degree of color after cleaning was less than 20 units according to Hazen (180 units for tetra-2-ethylhexnoate), which corresponds to the standards in GOST 29131-91 (ISO 2211-73). The esterification rates were compared, and it was shown that the quantitative yields of isomeric tetraesters at 100–110 Β°C were achieved in 12–15 h for isobutyric and isovaleric acids, 25–27 h for 2-ethyl-hexanoic acid, and ~40 h for pivalic acid. Β Π¦Π΅Π»ΠΈ. Π‘Π»ΠΎΠΆΠ½Ρ‹Π΅ эфиры пСнтаэритрита Π·Π° счСт своСй структуры ΠΎΠ±Π»Π°Π΄Π°ΡŽΡ‚ рядом ΠΏΡ€ΠΈΠ²Π»Π΅ΠΊΠ°Ρ‚Π΅Π»ΡŒΠ½Ρ‹Ρ… свойств: высоким индСксом вязкости ΠΏΡ€ΠΈ ΠΈΡ… использовании Π² качСствС масСл ΠΈ ΠΎΡ‚Π»ΠΈΡ‡Π½ΠΎΠΉ ΡΠΎΠ²ΠΌΠ΅ΡΡ‚ΠΈΠΌΠΎΡΡ‚ΡŒΡŽ с ΠΏΠΎΠ»ΠΈΠ²ΠΈΠ½ΠΈΠ»Ρ…Π»ΠΎΡ€ΠΈΠ΄Π½Ρ‹ΠΌΠΈ (ΠŸΠ’Π₯) ΠΏΠΎΠ»ΠΈΠΌΠ΅Ρ€Π°ΠΌΠΈ ΠΏΡ€ΠΈ ΠΈΡ… использовании Π² качСствС пластификаторов. ΠŸΡ€ΠΈ этом исходным ΡΡ‹Ρ€ΡŒΠ΅ΠΌ для производства ΠΊΠ°ΠΊ пСнтаэритрита, Ρ‚Π°ΠΊ ΠΈ ΠΊΠ°Ρ€Π±ΠΎΠ½ΠΎΠ²Ρ‹Ρ… кислот ΠΌΠΎΠΆΠ΅Ρ‚ ΡΠ»ΡƒΠΆΠΈΡ‚ΡŒ ΠΏΡ€ΠΈΡ€ΠΎΠ΄Π½Ρ‹ΠΉ Π³Π°Π·, Ρ‡Ρ‚ΠΎ Π°ΠΊΡ‚ΡƒΠ°Π»ΡŒΠ½ΠΎ с Ρ‚ΠΎΡ‡ΠΊΠΈ зрСния сниТСния объСмов Π³Π°Π·Π°, направляСмого Π½Π° сТиганиС, ΠΈ Π΅Π³ΠΎ использованиС Π² производствС химичСской ΠΏΡ€ΠΎΠ΄ΡƒΠΊΡ†ΠΈΠΈ. ЦСль Ρ€Π°Π±ΠΎΡ‚Ρ‹ – Ρ€Π°Π·Ρ€Π°Π±ΠΎΡ‚ΠΊΠ° Π½ΠΎΠ²Ρ‹Ρ… ΠΌΠ΅Ρ‚ΠΎΠ΄ΠΎΠ² синтСза тСтраэфиров пСнтаэритрита ΠΈ алифатичСских ΠΈΠ·ΠΎΠΌΠ΅Ρ€Π½Ρ‹Ρ… кислот Π‘4–Б8.ΠœΠ΅Ρ‚ΠΎΠ΄Ρ‹. ΠŸΡ€ΠΎΡ†Π΅ΡΡ ΠΏΡ€ΠΎΠ²ΠΎΠ΄ΠΈΠ»ΠΈ Π² Ρ€Π΅ΠΆΠΈΠΌΠ΅ самокатализа ΠΏΡ€ΠΈ ΠΈΠ·Π±Ρ‹Ρ‚ΠΊΠ΅ кислоты Π² мольном ΡΠΎΠΎΡ‚Π½ΠΎΡˆΠ΅Π½ΠΈΠΈ 8:1, Π° Ρ‚Π°ΠΊΠΆΠ΅ Π² присутствии растворитСля (Ρ‚ΠΎΠ»ΡƒΠΎΠ»Π°) ~30% Π½Π° Ρ€Π΅Π°ΠΊΡ†ΠΈΠΎΠ½Π½ΡƒΡŽ массу, ΠΎΠ±Π΅ΡΠΏΠ΅Ρ‡ΠΈΠ²Π°ΡŽΡ‰Π΅Π³ΠΎ Ρ€Π°Π²Π½ΠΎΠΌΠ΅Ρ€Π½Ρ‹ΠΉ ΠΎΡ‚Π³ΠΎΠ½ Ρ€Π΅Π°ΠΊΡ†ΠΈΠΎΠ½Π½ΠΎΠΉ Π²ΠΎΠ΄Ρ‹ ΠΏΡ€ΠΈ постоянной Ρ‚Π΅ΠΌΠΏΠ΅Ρ€Π°Ρ‚ΡƒΡ€Π΅ 100–110 Β°Π‘, ΡƒΠΌΠ΅Π½ΡŒΡˆΠ΅Π½ΠΈΠ΅ ΠΏΡ€ΠΎΠ΄ΡƒΠΊΡ‚ΠΎΠ² ΠΏΠΎΠ±ΠΎΡ‡Π½Ρ‹Ρ… Ρ€Π΅Π°ΠΊΡ†ΠΈΠΉ ΠΈ ΠΏΠΎΠ²Ρ‹ΡˆΠ΅Π½ΠΈΠ΅ сСлСктивности процСсса. ΠŸΡ€ΠΎΠ΄ΡƒΠΊΡ‚Ρ‹ ΠΈΠ· Ρ€Π΅Π°ΠΊΡ†ΠΈΠΎΠ½Π½ΠΎΠΉ массы выдСляли ΠΌΠ΅Ρ‚ΠΎΠ΄ΠΎΠΌ Π²Π°ΠΊΡƒΡƒΠΌΠ½ΠΎΠΉ Ρ€Π΅ΠΊΡ‚ΠΈΡ„ΠΈΠΊΠ°Ρ†ΠΈΠΈ. Π˜Π΄Π΅Π½Ρ‚ΠΈΡ„ΠΈΠΊΠ°Ρ†ΠΈΡ всСх синтСзированных тСтраэфиров ΠΏΡ€ΠΎΠ²Π΅Π΄ΠΈΠ»Π°ΡΡŒ с использованиСм хроматомасс-спСктромСтричСского Π°Π½Π°Π»ΠΈΠ·Π°.Π Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚Ρ‹. Π’ Ρ€Π°Π±ΠΎΡ‚Π΅ ΠΏΡ€Π΅Π΄Π»ΠΎΠΆΠ΅Π½Ρ‹ Π²Π°Ρ€ΠΈΠ°Π½Ρ‚Ρ‹ ΠΎΠΏΡ‚ΠΈΠΌΠΈΠ·Π°Ρ†ΠΈΠΈ условий тСрмичСской этСрификации пСнтаэритрита ΠΈΠ·ΠΎΠΌΠ΅Ρ€Π½Ρ‹ΠΌΠΈ ΠΌΠΎΠ½ΠΎΠΊΠ°Ρ€Π±ΠΎΠ½ΠΎΠ²Ρ‹ΠΌΠΈ кислотами (изомасляной, ΠΈΠ·ΠΎΠ²Π°Π»Π΅Ρ€ΠΈΠ°Π½ΠΎΠ²ΠΎΠΉ, ΠΏΠΈΠ²Π°Π»Π΅Π²ΠΎΠΉ, 2-этилгСксановой), ΠΎΠ±Π»Π°Π΄Π°ΡŽΡ‰ΠΈΠΌΠΈ Π·Π° счСт своСй структуры Ρ€Π°Π·Π»ΠΈΡ‡Π½ΠΎΠΉ Ρ€Π΅Π°ΠΊΡ†ΠΈΠΎΠ½Π½ΠΎΠΉ ΡΠΏΠΎΡΠΎΠ±Π½ΠΎΡΡ‚ΡŒΡŽ. Π Π°Π·Ρ€Π°Π±ΠΎΡ‚Π°Π½Ρ‹ ΠΌΠ΅Ρ‚ΠΎΠ΄ΠΈΠΊΠΈ выдСлСния тСтраэфиров пСнтаэритрита ΠΈ ΡΠΎΠΎΡ‚Π²Π΅Ρ‚ΡΡ‚Π²ΡƒΡŽΡ‰ΠΈΡ… кислот. ΠŸΠΎΠ»ΡƒΡ‡Π΅Π½Ρ‹ характСристики основных сСрий ΠΈΠΎΠ½ΠΎΠ² тСтраэфиров пСнтаэритрита ΠΈ алифатичСских ΠΈΠ·ΠΎΠΌΠ΅Ρ€Π½Ρ‹Ρ… кислот Π‘4–Б8 Π² масс-спСктрах.Π’Ρ‹Π²ΠΎΠ΄Ρ‹. Π’ ΠΏΡ€Π΅Π΄Π»ΠΎΠΆΠ΅Π½Π½Ρ‹Ρ… условиях провСдСния процСсса Π²Ρ‹Ρ…ΠΎΠ΄ тСтраэфиров составил 95–96% ΠΎΡ‚ тСорСтичСского с чистотой Π½Π΅ ΠΌΠ΅Π½Π΅Π΅ 99.6%. ΠŸΠΎΠ»ΡƒΡ‡Π΅Π½Π½Ρ‹Π΅ Ρ†Π΅Π»Π΅Π²Ρ‹Π΅ ΠΏΡ€ΠΎΠ΄ΡƒΠΊΡ‚Ρ‹ (тСтраэфиры) Ρ…Π°Ρ€Π°ΠΊΡ‚Π΅Ρ€ΠΈΠ·ΡƒΡŽΡ‚ΡΡ ΠΎΡ‚Π½ΠΎΡΠΈΡ‚Π΅Π»ΡŒΠ½ΠΎΠΉ Ρ†Π²Π΅Ρ‚ΠΎΡΡ‚Π°Π±ΠΈΠ»ΡŒΠ½ΠΎΡΡ‚ΡŒΡŽ: максимальная ΡΡ‚Π΅ΠΏΠ΅Π½ΡŒ ΠΎΠΊΡ€Π°ΡˆΠ΅Π½Π½ΠΎΡΡ‚ΠΈ послС очистки составляСт Π½Π΅ Π±ΠΎΠ»Π΅Π΅ 20 Π΅Π΄. ΠΏΠΎ Π₯Π°Π·Π΅Π½Ρƒ (для Ρ‚Π΅Ρ‚Ρ€Π°-2-этилгСксаноата – 180), Ρ‡Ρ‚ΠΎ соотвСтствуСт Π“ΠžΠ‘Π’ 29131-91 (ИБО 2211-73). ΠšΠΎΠ»ΠΈΡ‡Π΅ΡΡ‚Π²Π΅Π½Π½Ρ‹Π΅ Π²Ρ‹Ρ…ΠΎΠ΄Ρ‹ ΠΈΠ·ΠΎΠΌΠ΅Ρ€Π½Ρ‹Ρ… тСтраэфиров ΠΏΡ€ΠΈ 100–110 Β°Π‘ Π΄ΠΎΡΡ‚ΠΈΠ³Π°ΡŽΡ‚ΡΡ: Π·Π° 12–15 Ρ‡ для изомасляной ΠΈ ΠΈΠ·ΠΎΠ²Π°Π»Π΅Ρ€ΠΈΠ°Π½ΠΎΠ²ΠΎΠΉ кислоты, 25–27 Ρ‡ для 2-этил-гСксановой ΠΈ ~40 Ρ‡ для ΠΏΠΈΠ²Π°Π»Π΅Π²ΠΎΠΉ кислоты

    Insulin Status and Vascular Responses to Weight Loss in Obesity

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    ObjectivesThe aim of this study was to determine whether the effects of weight loss on arterial function are differentially modified by insulin status.BackgroundClinical studies suggest that plasma insulin levels may predict the extent of cardiovascular benefit achieved with weight loss in obese individuals, but mechanisms are currently unknown.MethodsWe prospectively followed 208 overweight or obese patients (body mass index [BMI]Β β‰₯25 kg/m2) receiving medical/dietary (48%) or bariatric surgical (52%) weight-loss treatment during a median period of 11.7 months (interquartile range: 4.6 to 13 months). We measured plasma metabolic parameters and vascular endothelial function using ultrasound at baseline and following weight-loss intervention and stratified analyses by median plasma insulin levels.ResultsPatients age 45 Β± 1 years, with BMI 45 Β± 9 kg/m2, experienced 14 Β± 14% weight loss during the study period. In individuals with higher baseline plasma insulin levels (above median >12 ΞΌIU/ml; nΒ = 99),Β β‰₯10% weight loss (compared withΒ <10%) significantly improved brachial artery macrovascular flow-mediated vasodilation and microvascular reactive hyperemia (pΒ < 0.05 for all). By contrast, vascular function did not change significantly in the lower insulin group (≀12 ΞΌIU/ml; nΒ = 109) despite a similar degree of weight loss. In analyses using a 5% weight loss cut point, only microvascular responses improved in the higher insulin group (pΒ = 0.02).ConclusionsInsulin status is an important determinant of the positive effect of weight reduction on vascular function with hyperinsulinemic patients deriving the greatest benefit. Integrated improvement in both microvascular and macrovascular function was associated withΒ β‰₯10% weight loss. Reversal of insulin resistance and endothelial dysfunction may represent key therapeutic targets for cardiovascular risk reduction in obesity
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