3,278 research outputs found
Thermal deformation of concentrators in an axisymmetric temperature field
Axisymmetric thermal deformations of paraboloid mirrors, due to heating, are examined for a mirror with a optical axis oriented toward the Sun. A governing differential equation is derived using Mushtari-Donnel-Vlasov simplifications, and a solution is presented which makes it possible to determine the principal deformation characteristics
A Double-Mode RR Lyrae Star with a Strong Fundamental Mode Component
NSVS 5222076, a thirteenth magnitude star in the Northern Sky Variability
Survey, was identified by Oaster as a possible new double-mode RR Lyrae star.
We confirm the double-mode nature of NSVS 5222076, supplementing the survey
data with new V band photometry. NSVS 5222076 has a fundamental mode period of
0.4940 day and a first overtone period of 0.3668 day. Its fundamental mode
light curve has an amplitude twice as large as that of the first overtone mode,
a ratio very rarely seen. Data from the literature are used to discuss the
location in the Petersen diagram of double-mode RR Lyrae stars having strong
fundamental mode pulsation. Such stars tend to occur toward the short period
end of the Petersen diagram, and NSVS 5222976 is no exception to this rule.Comment: 14 pages, 4 figures, To be published in the March, 2006, issue of
PAS
СВЕРХНОРМАТИВНЫЕ СБРОСЫ ЗАГРЯЗНЯЮЩИХ ВЕЩЕСТВ: ПРОБЛЕМЫ МЕТОДИКИ УСТАНОВЛЕНИЯ ПРИЧИНЕННОГО УЩЕРБА
The article deals with environmental law peculiarities with excess discharges of pollutants (EDP) within the system of the state regulation of water use. It presents the basic theoretical provisions for a comprehensive methods of a forensic engineer, environmental and economic examination of damages incurred by the state as the result of excess discharges ofpollutants into water bodies. This methods solves the following tasks: confirms the facts of EDP registered by the bodies of Ukrainian State Environmental Inspection (USEI) and determines the properties of these EDPs; confirms the initial data collected by USEI to calculate damages; confirms and/or determines the amount of damages. The first task has a priority and is solved by inspecting: the conditions with regard to which the calculation of damages has been carried out; the fact whether the technical object of discharge meets hydraulic requirements; the study of the event and temporal structure of the period when the violation took place, identification of elementary events on the control of return water, control such episodes; determining the characteristics of control events; depiction of the EDP structure with a matrix model.Розглянуто еколого-правові особливості, місце й значення наднормативних скидань забруднюючих речовин у системі державного регулювання водокористування. Викладено основні теоретичні положення комплексної методики судової інженерно-екологічної та економічної експертизи збитків, заподіяних державі наднормативними скиданнями забруднюючих речовин у водні об’єкти
Эффективность продленной блокады фасциальной плоскости мышцы, выпрямляющей спину, при множественных переломах ребер
Objctive. To evaluate the analgesic efficacy of prolonged erector spinae fascial plane (ESFP) block in patients with multiple rib fractures.Material and methods. The study included 40 patients with multiple rib fractures. Based on anesthesia methods, patients were divided into 2 groups, where systemic analgesics were used for pain management in the control group (N=20), and additional supplementation with prolonged erector spinae fascial plane (ESFP) block in the main group (N=20). The study monitored the severity of pain measured by the numeric rating scale (NRS) at rest and during coughing, forced vital capacity (FVC), and the need for injectable narcotic analgesics.Results. The NRS measures at rest in the main group were statistically significantly superior to the control group results: at stage II — 1.5 points (IQR: 1.0–3.0) vs 3.0 points (IQR: 3.0–4.0); at stage III — 2.0 points (IQR: 1.0–2.0) vs 4.0 points (IQR: 3.0–5.0); at stage IV — 1.5 points (IQR: 0.8–2.2) vs. 4.5 points (IQR: 4.0–5.0); at stage V — 1 point (IQR: 0–2,0) vs. 3.0 points (IQR: 2.8–4.0), respectively (P0.001). Percentages of predicted FVC depending on patient’s gender, age, height and weight in the control group were as follows: at stage II — 38± 8% (95%CI: 34–41); stage III — 44± 8% (95%CI: 40–47); stage IV — 41±10% (95%CI: 36–45) and stage V — 49±10% (95%CI: 45–53). In the main group, the following FVC values were obtained: 49±15% at stage II (95%CI: 42–56), 50±13% at stage III (95%CI: 44–57), 53±13% at stage IV (95%CI: 47–59), and 57±11% at stage V (95%CI: 52–63). Therefore, statistically significant FVC reduction in the control group vs the main group came up to 22%, 14%, 24% and 15% at stages II-V, respectively (P0.05). The amounts of injected narcotic analgesics on day 1 and day 2 after initiation of the study were 5.0 mg (IQR: 5–10) and 5.0 mg (IQR: 0–5.0) in the main group vs 10.0 mg (IQR: 5.0–15.0) and 7.5 mg (IQR: 5.0–10.0) in the control group, respectively (P0.05).Conclusion. The prolonged erector spinae fascial plane block improves the quality of analgesia and FVC values in patients with multiple rib fractures.Цель исследования. Оценить эффективность продленной блокады фасциальной плоскости мышцы, выпрямляющей спину, у пациентов с множественными переломами ребер.Материал и методы. В исследование включили 40 больных с множественными переломами ребер. В зависимости от способа обезболивания переломов ребер больных разделили на 2 группы, где в контрольной группе (n=20) обезболивание проводили системными анальгетиками, а в основной группе (n=20), помимо системных анальгетиков, обезболивание дополняли продленной блокадой мышцы, выпрямляющей спину, в фасциальной плоскости. Измеряли выраженность боли по цифровой рейтинговой шкале боли (ЦРШ) в покое и при кашле, форсированную жизненную емкость легких, потребность в инъекционных наркотических анальгетиках.Результаты. Показатель ЦРШ в покое в основной группе был статистически значимо выше по сравнению с контрольной группой: на II этапе — 1,5 балла (IQR: 1,0–3,0) против 3,0 баллов (IQR: 3,0–4,0); на III этапе — 2,0 балла (IQR: 1,0–2,0) против 4,0 баллов (IQR: 3,0–5,0); на IV этапе — 1,5 балла (IQR: 0,8–2,2) против 4,5 баллов (IQR: 4,0–5,0); на V этапе — 1 балл (IQR: 0–2,0) против 3,0 баллов (IQR: 2,8–4,0), соответственно (p0,001). Показатель ФЖЕЛ в контрольной группе в процентном соотношении, в зависимости от должной по полу, возрасту, росту и весу пациента, составил на II этапе — 38±8% (95%CI: 34–41); III этапе — 44±8% (95%CI: 40–47); IV этапе — 41±10% (95%CI: 36–45) и V этапе — 49±10 % (95%CI: 45–53). В основной группе ФЖЕЛ составил на II этапе — 49±15% (95%CI: 42–56), III этапе — 50±13% (95%CI: 44–57), IV этапе 53±13% (95%CI: 47–59) и V этапе 57±11% (95%CI: 52–63), что, соответственно, было на 22%, 14%, 24% и 15% статистически значимо меньше, чем в основной группе (p0,05). Потребление наркотических анальгетиков в 1-е и 2-е сутки после начала исследования в основной группе составило 5,0 мг (IQR: 5–10) и 5,0 мг (IQR: 0–5,0) против 10,0 мг (IQR: 5,0–15,0) и 7,5 мг (IQR: 5,0–10,0) в контрольной группе, соответственно (p0,05).Заключение. Продленная блокада фасциальной плоскости мышцы, выпрямляющей спину, улучшает качество обезболивания и увеличивает показатели ФЖЕЛ у больных с множественными переломами ребер
The neotypification of Frontonia vernalis (Ehrenberg, 1833) Ehrenberg, 1838 and the description of Frontonia paravernalis sp. nov. trigger a critical revision of frontoniid systematics
Background: Among Oligohymenophorea (Ciliophora, Alveolata) the subclass Peniculia stands as one of the most
well-known groups. Frontonia is the largest genus of Peniculia, and its representatives are spread in any type of
water bodies as well as in soil. At a first glance, Frontonia species exhibit an overall similar morphology, and form a
well-recognizable taxon of ciliates. Despite the general morphological homogeneity, the phylogenetic analysis
based on the 18S rDNA sequencing showed that Frontonia is a non-monophyletic group. The systematics of this
genus should be deeply reviewed, although additional issues complicate the task solving. First, type species of the
genus is not yet clearly established, and no type material is available. In this context, the situation of F. vernalis, one
of the first Frontonia ever described, is somehow puzzled: the description of this ciliate made by Ehrenberg (in 1833
and 1838) contains several inaccuracies and subsequent misidentifications by other authors occurred. Moreover, the
18S rDNA sequence of a putative F. vernalis is available on GenBank, but no morphological description of the
correspondent specimens is provided; thus, in our opinion, it should be only prudently associated with F. vernalis or
at least indicated as “F. vernalis”.
Results: In the present work, we provide the neotypification of F. vernalis newly found in Italy, presenting its
multidisciplinary description and its neotype material. Similarly, we describe a novel species bearing Chlorella-like
endosymbionts, Frontonia paravernalis sp. nov., retrieved in two far distant locations (Italy, Russia). A critical
discussion on the status of Frontonia taxonomy and phylogeny is also presented, based on the 18S rDNA
sequencing of both these two newly collected species and other 14 frontoniids isolated in different parts of the
world. Finally, in the present study F. leucas was neotypified and proposed as the type species of the genus.
Conclusions: Green frontoniids form a monophyletic clade of freshwater organisms characterized by having a
single contractile vacuole and bearing intracytoplasmatic Chlorella-like symbionts. With the neotypification of F.
vernalis and F. leucas a fundamental step in Frontonia systematics was taken, and the bases for further taxonomic
studies were laid
Strains of Paramecium quadecaurelia from Namibia, Africa; Genetic and Molecular Studies
Summary. New strains of Paramecium quadecaurelia were found in Namibia, Africa. Previously, this species from the P. aurelia complex was known only from Australia, Emily Gap. Namibian strains were identified by mating reaction; their relationship with the Australian strain was studied by classical strain crosses (survival in F1 and F2 generations) and by comparison of cytosol-type hsp70 gene sequences. Phylogenetic trees of the Namibian and Australian strains of P. quadecaurelia and the other species of the P. aurelia complex were generated based on the maximum-likelihood method
Rare Freshwater Ciliate Paramecium chlorelligerum Kahl, 1935 and Its Macronuclear Symbiotic Bacterium "Candidatus Holospora parva"
Ciliated protists often form symbioses with many diverse microorganisms. In particular, symbiotic associations between ciliates and green algae, as well as between ciliates and intracellular bacteria, are rather wide-spread in nature. In this study, we describe the com- plex symbiotic system between a very rare ciliate, Paramecium chlorelligerum, unicellular algae inhabiting its cytoplasm, and novel bacteria colonizing the host macronucleus. Para- mecium chlorelligerum, previously found only twice in Germany, was retrieved from a novel location in vicinity of St. Petersburg in Russia. Species identification was based on both clas- sical morphological methods and analysis of the small subunit rDNA. Numerous algae occu- pying the cytoplasm of this ciliate were identified with ultrastructural and molecular methods as representatives of the Meyerella genus, which before was not considered among symbi- otic algae. In the same locality at least fifteen other species of “green” ciliates were found, thus it is indeed a biodiversity hot-spot for such protists. A novel species of bacterial symbi- onts living in the macronucleus of Paramecium chlorelligerum cells was morphologically and ultrastructurally investigated in detail with the description of its life cycle and infection capabilities. The new endosymbiont was molecularly characterized following the full-cycle rRNA approach. Furthermore, phylogenetic analysis confirmed that the novel bacterium is a member of Holospora genus branching basally but sharing all characteristics of the genus except inducing connecting piece formation during the infected host nucleus division. We propose the name “Candidatus Holospora parva” for this newly described species. The described complex system raises new questions on how these microorganisms evolve and interact in symbiosis
Morphology, ultrastructure, and molecular phylogeny of the ciliate Sonderia vorax with insights into the systematics of order Plagiopylida
BACKGROUND: Ciliates of the family Sonderiidae are common members of the eukaryotic communities in various anoxic environments. They host both ecto- and endosymbiotic prokaryotes (the latter associated with hydrogenosomes) and possess peculiar morpho-ultrastructural features, whose functions and homologies are not known. Their phylogenetic relationships with other ciliates are not completely resolved and the available literature, especially concerning electron microscopy and molecular studies, is quite scarce. RESULTS: Sonderia vorax Kahl, 1928 is redescribed from an oxygen-deficient, brackish-water pond along the Ligurian Sea coastlines of Italy. Data on morphology, morphometry, and ultrastructure are reported. S. vorax is ovoid-ellipsoid in shape, dorsoventrally flattened, 130 x 69 μm (mean in vivo); it shows an almost spherical macronucleus, and one relatively large micronucleus. The ventral kinetom has a “secant system” including fronto-ventral and fronto-lateral kineties. A distinctive layer of bacteria laying between kineties covers the ciliate surface. Two types of extrusomes and hydrogenosomes-endosymbiotic bacteria assemblages are present in the cytoplasm. The phylogeny based on 18S rRNA gene sequences places S. vorax among Plagiopylida; Sonderiidae clusters with Plagiopylidae, although lower-level relationships remain uncertain. The studied population is fixed as neotype and the ciliate is established as type species of the genus, currently lacking. CONCLUSIONS: This is the first description of a representative of Sonderiidae performed with both morphological and molecular data. To sum up, many previous hypotheses on this interesting, poorly known taxon are confirmed but confusion and contradictory data are as well highlighted
Р-стереогенні діамандоїдні фосфіни
Despite diamondoid phosphines have found many synthetic applications and are even available commercially the chemistry of chiral diamondoid phosphines remains largely unexplored.Aim. To develop the convenient preparative method for the preparation of sterically-congested P-stereogenic secondary diamodoidyl phosphines as potential organocatalysts and ligands in the asymmetric synthesis.Results and discussion. A convenient method for the synthesis of P-stereogenic diamondoid phosphines with high yields through the phosphorylation of hydroxydiamondoids in trifluoroacetic acid followed by the reduction of the corresponding asymmetric chlorophosphonates has been proposed. The secondary phosphines obtained form stable complexes with borane that can be used to separate diamondoid phosphines into enantiomers.Experimental part. The experimental procedures for the preparation of 1- and 4-diamantyl-1-adamantyl- and phenylphosphines were developed; the structures of new compounds were confirmed by NMR and HRMS spectral data.Conclusions. A number of P-stereogenic mixed diamondoidylaryl phosphines and the secondary phosphines containing exclusively diamondoid substituents has been prepared. A degree of steric bulkiness is determined by the combination of diamondoid substituents around a phosphorus atom where 1-diamantyl derivatives are the most sterically-congested. The compounds obtained are potential ligands in asymmetric catalysis.Received: 31.03.2020Revised: 24.06.2020Accepted: 27.08.2020Незважаючи на те, що діамандоїдні фосфіни широко використовуються в органічному синтезі і навіть доступні комерційно, хімія хіральних діамандоїдних фосфінів залишається не дослідженою.Мета. Розробити зручний препаративний метод синтезу стереоускладнених Р-стереогенних вторинних діамандоїдних фосфінів, які можуть бути використані як ліганди в асиметричному синтезі, а також як органокаталізатори.Результати та їх обговорення. Запропоновано зручний метод синтезу P-стереогенних діамандоїдних фосфінів шляхом фосфорилювання гідроксипохідних діамандоїдів у трифтороцтовій кислоті з подальшим відновленням відповідних асиметричних хлорофосфонатів з високими виходами. Одержані таким чином фосфіни утворюють стійкі комплекси з бораном, які розглядаються як проміжні сполуки для подальшого розділення енантіомерів.Експериментальна частина. Був розроблений препаративний метод синтезу 1- і 4-діамантил-, 1-адамантил- і фенілфосфінів, структури яких підтверджено мас-спектрометричними і ЯМР-спектральними даними.Висновки. Одержано ряд Р-стереогенних змішаних діамандоїларилфосфінів та вторинних фосфінів, які містять виключно діамандоїдні замісники. Ступінь стеричного навантаження сполук визначається комбінацією діамандоїдних замісників навколо атома фосфору, де похідні 1-діамантилу найбільш стерично ускладнені. Одержані сполуки є потенційними лігандами в асиметричному каталізі.Received: 31.03.2020 Revised: 24.06.2020 Accepted: 27.08.202
Temperature Evolution of Sodium Nitrite Structure in a Restricted Geometry
The NaNO nanocomposite ferroelectric material in porous glass was
studied by neutron diffraction. For the first time the details of the crystal
structure including positions and anisotropic thermal parameters were
determined for the solid material, embedded in a porous matrix, in ferro- and
paraelectric phases. It is demonstrated that in the ferroelectric phase the
structure is consistent with bulk data but above transition temperature the
giant growth of amplitudes of thermal vibrations is observed, resulting in the
formation of a "premelted state". Such a conclusion is in a good agreement with
the results of dielectric measurements published earlier.Comment: 4 pages, 4 figure
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