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Background: It is increasingly recognized that complex abdominal wall reconstruction (cAWR) necessitates specialized training. No studies have been conducted to assess whether a volume-outcomes relationship is present in cAWR. We sought to determine if outcomes for patients undergoing cAWR varied based on surgeon volume among participants in the Abdominal Core Health Quality Collaborative (ACHQC). Methods: All patients with ventral hernias undergoing elective cAWR with component separation (lateral component release) were selected from ACHQC database. Surgeons were ranked based on annual number of cAWR procedures performed and then grouped in tertiles. Patient characteristics, hernia risk factors, operative details, and 30-days outcomes were evaluated. Results: A total of 9206 patients were identified, of which 310 (3.4%), 723 (7.9%) and 8173 (88.7%) cAWRs were performed by low (105 surgeons), medium (49) and high-volume (66) surgeons, respectively. Patients operated upon by high-volume surgeons tended to have more comorbidities and higher ASA class (72.5% of class ≥ III, vs 53.5%). Hernia characteristics demonstrated that high-volume surgeons more commonly operated on patients presenting with recurrent hernias (50.2% vs 42%), wider hernias (13.5 cm vs 10.5 cm), associated ostomies (13% vs 3.6%), and prior of surgical site infections (32% vs 26%, P= 0.035). High-volume surgeons more commonly performed posterior component separation procedures (92% vs 84%), utilized permanent mesh (92% vs 88%), and placed mesh in sublay position. In spite of operating on more advanced hernias, high-volume surgeons achieved comparable rates (all P> 0.4) of 30-day surgical site infections (SSI: 6.9% vs 7.1%) and surgical site occurrences requiring procedural intervention (SSO-PI: 8.9% vs 10%). Conclusions: High-volume surgeons maintain comparable outcomes following cAWR despite performing operations on patients with more comorbidities and advanced hernia disease. These findings should be integrated into the debates related to regionalizing abdominal wall reconstruction procedures among high-volume surgeons.

A 20 kW gyrotron-driver has been used to control the RF generation of a 170 GHz/1 MW ITER prototype gyrotron. The frequency-locked operation regime has been obtained, accompanied by an increase in power and efficiency as well as stabilization of the frequency of the slave MW-level tube.

A synthetic method for a primary 2-(thiophen-2′-yl)ethylphosphine was developed. The reaction of thiophenylethylphosphine with paraformaldehyde and primary arylamines leads to the formation of cyclic bisphosphines, namely, 1,5-di(aryl)-3,7-bis(thiophenylethyl)-1,5-diaza-3,7-diphosphacyclooctane (aryl = phenyl, p-tolyl). The obtained bisphosphines form cationic bis-P,P-chelate complexes with copper(I) tetrafluoroborate, which were structurally characterized by NMR spectroscopy, mass spectrometry, and elemental and XRD analyses. Surprisingly, the copper(I) complexes display a multiband emission in the solid state with maxima at 355–360, 425–430, and 480–490 nm and nanosecond lifetimes (1.2–1.4 ns) upon a 335 nm excitation. The excitation of the complexes at 360 nm at room temperature results in a deep-blue emission at 425–430 nm and a tail at 460–490 nm. A temperature decrease leads to an increased intensity of the emission band at 480 nm, while the luminescence lifetimes insignificantly increased up to 14 ns. Quantum chemical calculations explain the observed unusual luminescent behavior by the existence of “undistorted” and “flattened” singlet excited states of copper(I) complexes at room temperature and at 77 K, respectively.

A series of new cationic complexes [(PPh3)Au(L)](OTf) (L = 1,10-phenanthroline (phen) (1); 5,6-dimethyl-1,10-phenanthroline (dmphen) (2); 5,6-epoxy-5,6-dihydro-1,10-phenanthroline (ephen) (3); dimethyl 2,2’-biquinoline-4,4’-dicarboxylate (dmcbiq) (4); 2,3,4,5,6,7,8,9-octachloro-1,10-phenantroline (ocphen) (5)) were obtained in high yields by the standard ligand exchange reactions from [(PPh3)AuCl]. The compounds were characterized by analytical and spectroscopic methods. For all compounds, the crystal structure was established using X-ray diffraction analysis. In all structures, an atypical asymmetric mode of coordination of the diimine ligand (one shortened and the second elongated Au–N bond) was found, which is a consequence of the so-called antichelate effect. Structures 1–3with electron-donating substituents (H, methyl, epoxide) are the most asymmetric, while structures 4and 5with electron-withdrawing groups (CO2Me and Cl) are the least asymmetric. According to the results of the density functional theory (DFT) calculations, both Au–N bonds are covalent, and the geometry around gold(I) can be considered as a distorted triangular one. Cationic complexes [(PPh3)Au(L)]+form dimers in the crystal structure due to π–π interactions, the calculated energy of which reaches 4.2 kcal·mol–1in the case of structure 5. These dimers in 5additionally interact with OTf–anions through different kinds of contacts with a calculated total energy of 8.8 kcal·mol–1. Inside the {[(PPh3)Au(ocphen)]2}2+associates, intermolecular Au···Cl noncovalent interactions were also found. Remarkably, the dimers in 5are built through nonclassical π–π interactions between geometrically different parts of the ocphen ligand, which is a consequence of its asymmetric coordination to the gold(I) center. All complexes show multiple photoluminescence in the solid state at room temperature. The lifetimes of the excited state are in the microsecond range, which is characteristic of phosphorescence. Time-dependent DFT (TD-DFT) calculations reveal that electronic transitions of different nature are responsible for the photoluminescence of complexes 1–5.

The town of Oranienbaum, erstwhile summer residence of Catherine the Great and her husband, Peter III, lies slightly more than an hour from St. Petersburg by train. Off the raddar [...]

Titanium dioxide samples doped with different amounts of dysprosium were synthesized with the sol–gel template method. The structure of the obtained materials was investigated by X-ray fluorescence, scanning electron microscopy, X-ray diffraction (XRD), diffuse reflection spectroscopy, low-temperature adsorption–desorption of nitrogen, and inductively coupled plasma mass spectrometry. According to XRD, it is assumed that Dy3+ions are statistically distributed in the titanium dioxide phase, predominantly located in interstices or on the surface of TiO2crystallites. The diffraction patterns show no peaks characteristic of the Dy2O3phase, the average sizes of crystallites of doped samples decreased compared to the sizes of undoped samples from 16.9 to 7.0–7.6 nm, and the crystal lattice parameters of the obtained materials differ. The introduction of dysprosium into the structure of titanium dioxide reduced the energy of the band gap of the obtained materials from 2.83 to 2.67–2.78 eV, which makes it possible to use them as catalysts for the photooxidation of methyl orange, o- and m-xylenes in water using the visible light. The maximum photocatalytic activity of the oxidation of methyl orange, o- and m-xylenes is characterized by a TiO2sample containing 9.5% dysprosium (Dy(9.5)/TiO2)—after 2.5 h the degradation of o- and m-xylenes on this catalyst was approximately 80 and 95%, respectively. The degradation of methyl orange on the (Dy(9.5)/TiO2) sample was 73% after 3 h.

Background Complicated acute appendicitis (CAA) has been linked to extremes of age, racial and socioeconomic disparities, public insurance, and remote residency. CAA rate has been used from 2005 to 2018 as a health care quality metric, with the assumption that delay in treatment was a main cause of perforation. We studied factors that could contribute to CAA focusing on modifiable factors which could be altered as part of a health care delivery system.Materials and Methods All primary admissions for acute appendicitis (AA) from the 2010 Nationwide Inpatient Sample were linked to 2010 state-level physician density data. CAA was distinguished by codes for perforation, generalized peritonitis, or intra-abdominal abscess. A multivariable logistic regression model for CAA prediction was built.Results A total of 288 556 patients were admitted with AA and 86 272 (29.9%) had CAA. Independent factors, linked to CAA, included age outside the 10-39 range (odds ratio (OR) = 2.1-2.4 and all P< .001), male gender (OR = 1.2), malnutrition (OR = 6.2), diabetes mellitus (OR = 2.1), chronic anemias (OR = 1.9), nonprivate insurances (OR 1.2-1.5), nonmetropolitan patient’s residence (OR = 1.15), and Midwest region (OR = 1.2). Patient income and physician coverage were not significant factors after adjustment for all other covariates. Highest CAA fraction of 39.6% was noted in rural patients admitted to urban teaching facilities.Discussion Although provider coverage at the state level may seem adequate and not related to increased CAA rates, the distance patients traveled for their definitive surgical care correlated with higher rates of CAA. Adjusting physician distribution into nonurban settings closer to patients could decrease rates of CAA by diminishing time to definitive care.

Issues related to the history of the former Soviet Union and, especially, Russia, since the breakup of the USSR in 1991 are examined, focusing on the high price the society paid for its attempts at political and economic reform. Topics include the inevitablity of the change, aspects of the tragedy which were not necessary, present hopes, and the necessity for generations to pass before Russia can resolve its complicated difficulties.

The incidence of acute pancreatitis (AP) is characterized by circannual and geographical variation. The aim of this study was to describe seasonal variation and trends in hospitalizations for AP in the USA with respect to AP etiology.

Mesoporous silica (MPS) modified with nickel and MPS doped with dysprosium and modified with nickel have been synthesized by the template method. The adsorbents are characterized by various techniques such as transmission electron microscopy, scanning electron microscopy, X‐ray diffraction, inductively coupled plasma spectroscopy, and X‐ray fluorescence analyses. The adsorption properties of the synthesized samples have been investigated by inverse gas chromatography. Furthermore, thermodynamic characteristics of the adsorption of test compound belonging to different classes of organic compounds were obtained. In addition, the contributions of the energy of specific interactions to the total adsorption energy were calculated. It is also shown that entropy plays the determining role in the adsorption of test compounds on synthesized mesoporous materials. Adsorption of C6‐C8alkanes, methanol, ethanol, benzene, nitromethane, acetone, m‐xylene, p‐xylene, cyclohexene, diethyl ether, and influence of synthesis conditions on the heats of adsorption and specific interactions are discussed.

External carotid artery (ECA) stenosis is an independent mortality predictor. Additionally, concomitant ECA and internal carotid artery (ICA) stenosis progression has been associated with an increased risk of ipsilateral ischemic events in asymptomatic patients. Universally accepted ECA duplex velocity criteria, for the prediction of stenosis, do not exist.

Byline: Valeri A.Shmelev Yuri P.Serdobintsev In selecting a drilling rig for the actual geological environment of well construction, a decision support system can reduce the cost per unit, construction time [...]

After the Institute of Medicine (IOM) report To Err Is Humanhighlighted the impact of medical errors, the Agency for Healthcare Research and Quality (AHRQ) developed Patient-Safety Indicators (PSI) to improve quality by identifying potential inpatient safety problems. PSI-15 was created to study accidental punctures and lacerations (APL), but PSI-15 may underestimate APLs in populations of patients. This study compares PSI-15 with a more inclusive approach using a novel composite of secondary diagnostic and procedural codes.

Development of new generations of supersize heavy-duty highway trucks for cargoes transportation on long and super long distances between Europe, Asia and Far East is actual now. New trucks shall reduce amount of transport on roads and quantity of drivers, involved in the transportation, will raise economic efficiency and safety of transportations and reduce fuel consumption, CO2,and harmful emissions. Multilink trucks (number of trailed links is three and more and the total truck length is above 40 m) are to achieve designated purposes and thus are under the scope in the article. The advantages of multilink trucks are formed mainly by reducing the cost of power to overcome the aerodynamic resistance of each co-trailer unit in comparison with the head element. However, the airflow in every trailer-trailer gap has been not studied for articulated vehicles such as multilink highway trucks. This zone of the truck is characterized by a rather large length and height, and the condition of the air mass is influenced by airflow from the roof, side panels and area under the bottom of a truck links. A study of this task will help us to analyse aerodynamic losses mechanics in the trailer-trailer gap and to come to new effective and substantiated decision allowing power loss and thus fuel consumption reduction. The study lists the general calculation method evaluating the aerodynamic characteristics of the multilink truck on the base of numerical simulation of fluid dynamics using Flow Vision software. During calculation, there were determined speed distribution and power lines along the truck, the distribution of pressure on the truck surface, power and full drag coefficient. The results obtained allowed numerically evaluate the effect of the distance between the links on fuel consumption for multilink trucks and define the desired changes in their design.

Main purpose of the study is assessing reasonability for recovery, production and application of radiogenic lead as a coolant, neutron moderator and neutron reflector in advanced fast reactors and accelerator-driven systems (ADS). The following results were obtained: 1. Radiogenic lead with high content of isotope 208Pb can be extracted from thorium or mixed thorium-uranium ores because 208Pb is a final product of 232Th natural decay chain. 2. The use of radiogenic lead with high 208Pb content in advanced fast reactors and ADS makes it possible to improve significantly their neutron-physical and thermal-hydraulic parameters. 3. The use of radiogenic lead with high 208Pb content in advanced fast reactors as a coolant opens the possibilities for more intense fuel breeding and for application of well-known oxide fuel instead of the promising but not tested enough nitride fuel under the same safety parameters. 4. The use of radiogenic lead with high 208Pb content in advanced fast reactors as a neutron reflector opens a possibility for substantial elongation of prompt neutron lifetime. As a result, chain fission reaction in the reactor core could be slowed down, and the reactor operation could become safer. 5. The use of radiogenic lead with high 208Pb content in ADS as a coolant can upgrade substantially the level of neutron flux in the ADS blanket. Thus, favorable conditions could be formed in the ADS blanket for effective transmutation of radioactive wastes with low cross-sections of radiative neutron capture.

Three FeIII-MIheterometallic complexes with anions of cyclobutane-1,1-dicarboxylic acid (H2cbdc) dianions [MIFe(cbdc)2(H2O)2]n(MI= Na (1), Rb (2) or Cs (3)) were obtained, with the compounds being two-dimensional (2D)-coordination polymers built of bischelate moieties {Fe(cbdc)2(H2O)2}−bound with alkali metal ions. In 1, the two coordinated water molecules are in the cis-position, while in 2and 3they are in the trans-position. The DC magnetic data and ab initiocalculations demonstrate that Fe3+ions in 1possess a negative Dvalue, while those in 2and 3have a positive Dvalue. The easy-axis anisotropy found for 1is a rare example for Fe3+ions. A topological analysis of the compounds synthesized and a series of known mononuclear octahedrally coordinated Fe3+complexes (from Cambridge Structural Database) that are interconnected into a crystal structure by alkali metal cations in a way similar to complexes 1–3was carried out.

One view of sarcoidosis is that the term covers many different diseases. However, no classification framework exists for the future exploration of pathogenetic pathways, genetic or trigger predilections, patterns of lung function impairment, or treatment separations, or for the development of diagnostic algorithms or relevant outcome measures. We aimed to establish agreement on high-resolution CT (HRCT) phenotypic separations in sarcoidosis to anchor future CT research through a multinational two-round Delphi consensus process. Delphi participants included members of the Fleischner Society and the World Association of Sarcoidosis and other Granulomatous Disorders, as well as members' nominees. 146 individuals (98 chest physicians, 48 thoracic radiologists) from 28 countries took part, 144 of whom completed both Delphi rounds. After rating of 35 Delphi statements on a five-point Likert scale, consensus was achieved for 22 (63%) statements. There was 97% agreement on the existence of distinct HRCT phenotypes, with seven HRCT phenotypes that were categorised by participants as non-fibrotic or likely to be fibrotic. The international consensus reached in this Delphi exercise justifies the formulation of a CT classification as a basis for the possible definition of separate diseases. Further refinement of phenotypes with rapidly achievable CT studies is now needed to underpin the development of a formal classification of sarcoidosis.

The interaction of phosphorus-containing epoxy trifunctional monomer – triglycidyl phosphate (TGPhT), with europium(III) nitrate hexahydrate is studied. A dissolution of europium salt added into TGPhT is occurred due to the interaction of the cation with phosphoryl groups and oxygen atoms of the epoxy ring, that is accompanied by the opening reaction and led to the formation of a polymer. The interaction of triepoxide with salt is investigated by FTIR-spectroscopy and differential scanning calorimetry (DSC). The thermal stability of the samples is determined by combined method of thermogravimetry and differential scanning calorimetry (TG/DSC), coupled with a quadrupole mass spectrometry to identify the gaseous products evolved during the thermal analysis of the samples. The kinetic parameters of the curing reaction are computed by using Thermokinetics software. The interaction of TGPhT with europium nitrate is suggested to occur through opening of epoxy rings in the presence of europium ions via the mechanism of cationic polymerization. The cured epoxy polymer exhibits luminescent properties.

Main purpose of the study is justifying doping of protactinium-231 into fuel compositions of advanced nuclear reactors with the ultimate aim to improve their operation safety and economic efficiency. Protactinium-231 could be generated in thorium blankets of hybrid thermonuclear facilities. The following results were obtained: 1. Protactinium-231 has some favorable features for its doping into nuclear fuel; 2. Protactinium containing fuel compositions can be characterized by the higher values of fuel burn-up, the longer values of fuel lifetime and the better proliferation resistance; 3. as protactinium-231 is the stronger neutron absorber than uranium-238, remarkably lower amounts of protactinium-231 may be doped into fuel compositions. The free space could be occupied by materials which are able to improve heat conductivity and refractoriness of fuel. As a consequence, operation safety of nuclear reactors could be upgraded.

The interaction of a wide beam of intense 10.6 µm and 9.4 µm laser radiation with atmospheric CO2is studied. The threshold spectroscopic effect of explosive absorption have been obtained. In this effect the absorption coefficient of the atmosphere increases sharply owing to strong self-heating ([MATH] 700-1000 K) of the beam channel.

Main purpose of the study is justifying the use of molybdenum as a structural material of fuel elements for improving the safety of nuclear reactors. Particularity of the used molybdenum is that its isotopic composition corresponds to molybdenum, which is obtained as tailing during operation of the separation cascade for producing a material for medical diagnostics of cancer. The following results were obtained: A method for reducing the thermal constant of fuel elements for light water and fast reactors by using dispersion fuel in cylindrical fuel rods containing, for example, granules of metallic U-Mo-alloy into Mo-matrix was proposed; the necessity of molybdenum enrichment by weakly absorbing isotopes was shown; total use of isotopic molybdenum will be more than 50 %.

As a rule, materials of small atomic weight (light and heavy water, graphite, and so on) are used as neutron moderators and reflectors. A new very heavy atomic weight moderator is proposed - radiogenic lead consisting mainly of isotope 208Pb. It is characterized by extremely small neutron radiative capture cross section ([approximately]0.23 mb for thermal neutrons, i.e., less than that for graphite and deuterium) and highest albedo of thermal neutrons.The use of radiogenic lead to make it possible to slow down the chain fission reaction on prompt neutrons in a fast reactor is evaluated. This can improve the safety of a fast reactor.It is noteworthy that radiogenic lead with high 208Pb content may be recovered from thorium (as well as thorium-uranium) ores without isotope separation. This has been confirmed experimentally by the investigations performed at the University of São Paulo in Brazil.

Two-pulse control of time-dependent anisotropy in liquid carbon tetrachloride at room temperature is implemented by using femtosecond polarisation spectroscopy. The liquid is excited by a train of two linearly polarised laser pulses, and the state of anisotropy is probed by a weak third pulse with registration of the optical Kerr effect. It is shown that by varying the delay between the exciting pulses and their relative intensity, selection of contributions of individual intramolecular modes into the recorded signal is achieved.

Abstract: The results of the structural study of the Nizhny Tagil platiniferous massif in the Central Urals are presented. This is a classic massif of the Ural-Alaskan-type zonal dunite-clinopyroxenite complexes. The massif is characterized by a nearly concentric vertical planar internal structure conformable to petrographic zoning (layering). The primary ultramafic rocks are distinguished by adcumulative protogranular structure with relict euhedral olivine protocrysts and distinct linear orientation of minerals, which was formed as a result of magmatic flow. The deformational linear and planar structures conformable to the early structural elements were formed in the process of subsequent coaxal high-temperature ductile flow. At this stage, dynamometamorphic zoning is formed, expressed in the change of the protogranular microstructure typical of the inner portion of the massif by porphyroclastic and mosaic microstructures in its marginal part. The country rocks underwent conjugate high-temperature metamorphism with the formation of hornfels and kytlymite. The structure of the massif is considered to be a result of dynamic differentiation in the course of magmatic flow followed by high-temperature coaxal flow during intrusive and diapiric ascent of rocks to the crustal level.

AbstractIn the opinion of some experts in problems of nuclear nonproliferation, the threat that subnational terrorist groups may become owners of gas centrifuges is real. If enrichment of feeding uranium increases from 0.7 to 20%, then the scope of separative works and amount of the feeding uranium needed for uranium enrichment up to the weapons-grade level decreases by many times. In this connection it can be expected that a potential nuclear proliferator will use gas centrifuges for illegal reenrichment of 20% uranium, taken from export deliveries for research reactors or from any other sources, up to weapons-grade quality and then manufacture a crude nuclear explosive device. These reasons indicate that besides reduction of uranium enrichment to 20% 235U, other measures may also be required to upgrade self-protection of 20% uranium against its unauthorized reenrichment.Denaturing of 20% uranium due to the admixture of small 232U amounts (~0.1%) creates an effective barrier against its renrichment up to the weapons-grade level because in the reenriching process the following occurs: (a) the content of 232U increases; (b) the internal source of alpha radiation intensifies; (c) UF6molecules are destroyed by alpha particles from decays of 232U with generation of low-volatile uranium fluorides and free fluorine; and (d) the neutron emission rate intensifies too, and this results in a cardinal reduction of energy yield from the chain fission reaction (CFR) by three orders of magnitude. So, uranium denatured with 232U becomes quite unattractive for potential nuclear proliferators.The authors are continuing the studies on the effects induced by the 232U admixture on the radiation resistance of UF6and on the energy yield of CFR in reenriched uranium.

The article studies the Russian “anekdot” as a specific speech genre and its transformation in this century. It gives an account of the rules of telling jokes in Russian: formal means of introduction of a joke text into discourse, the setting of context, the “linguistic masks” of joke characters (linguistic clichés, accent, typical grammar mistakes, etc.), which correlate with their “behavior masks.” The article discusses the conceptualization of the world in Russian jokelore, what is taken for granted in Russian jokes, what one need to know to understand them, and the transformation of the”anekdot” in the last two decades. Canned jokes are very popular in Russia; joke-telling is practiced in everywhere among all ages. Several new characters of Russian jokelore have emerged since 1990. But reference to jokes has become more popular than joketelling nowadays. The paper looks at ways of using jokes in the present-day discourse (in particular, indirect allusions to jokes). Finally, the paper discusses some issues in the translation of jokes from and into Russian. In order to achieve a desired effect in the target language, it is sometimes necessary to change the characters of the original joke or to add an introduction.

Abstract: A multifunctional computer Fourier spectrum analyzer is described intended for investigating electric signals in real time and for measuring the parameters of analog-to-digital converters.

RF systems in the ion cyclotron resonance frequency (ICRF) range and electron cyclotron resonance frequency (ECRF) range are in an advanced stage of commissioning, to carry out pre-ionization, breakdown, heating and current drive experiments on the steady-state superconducting tokamak SST-1. Initially the 1.5?MW continuous wave ICRF system would be used to heat the SST-1 plasma to 1.0?keV during a pulse length of 1000?s. For different heating scenarios at 1.5 and 3.0?T, a wide band of operating frequencies (20-92?MHz) is required. To meet this requirement two CW 1.5?MW rf generators are being developed in-house. A pressurized as well as vacuum transmission line and launcher for the SST-1-ICRF system has been commissioned and tested successfully. A gyrotron for the 82.6?GHz ECRF system has been tested for a 200?kW/1000?s operation on a water dummy load with 17% duty cycle. High power tests of the transmission line have been carried out and the burn pattern at the exit of transmission line shows a gaussian nature. Launchers used to focus and steer the microwave beam in plasma volume are characterized by a low power microwave source and tested for UHV compatibility. Long pulse operation has been made feasible by actively cooling both the systems. In this paper detailed test results and the present status of both the systems are reported.

This paper discusses the dynamics of the formation of absorbing layers in a conventional atomizer with transverse heating and in a two-stage atomizer. An experimental apparatus is described that provides digital recording of the optical density with temporal, spectral, and spatial resolution in the cross section of the atomizer. The influence of pyrolysis on the formation of atomic and nonselective-absorption signals in a two-state atomizer is investigated. Using the atomization of sodium chloride as an example, it is shown that the use of high-temperature pyrolysis and an additional vaporization stage - fractional condensation - in a two-state atomizer makes it possible to lower the level and the degree of spatial inhomogeneity of nonselective absorption. © 2004 Optical Society of America

Substrate activation of the sarcoplasmic reticulum Ca2+-ATPase of skeletal muscles of ectothermic (the ground frog Rana temporariaand a Black Sea fish, the chuco Dasyatis pastinaca) and endothermic (rabbit) animals was studied. Comparison of kinetic dependencies (von [S]) of this process for ectothermic animals with similar dependencies for endothermic animals has revealed their principal similarity. The cooperative character of the studied process in the millimolar ATP concentration range is discussed.

Acoustic charge transport is studied experimentally and theoretically. To this end, an AlGaAs/GaAs heterostructure is designed and fabricated with set geometrical and electrical parameters of the layers. Its transfer characteristic is measured, i.e., the variation of output voltage with injection current. The behavior of the curve is explained within an analytical model. The conclusions are supported by numerical simulation.

In view of the poor transmutation environments in fission reactors, elimination of long-lived fission products (FPs) remains an unresolved problem in the quest for a harmonized nuclear energy system. Since plasma fusion technology could provide effective neutron support, it is important to elaborate the qualities, features, and dimensions of a fusion neutron source exclusively oriented to FP transmutation, and this forms the main objective of this paper. Recent trends in fusion technology are examined to shape the conceptual blanket design features for D-T- and D-D-driven transmuters that match the demanding set of transmutation requirements. Material behavior under neutron irradiation in these blankets constitutes the central issue underlying this paper and yields the operational limits and radiological cost of FP incineration.

Accidents with rupture of a reactor core can contaminate large regions. One way to reduce the time required to determine the scenario can be to perform a preliminary survey using nonspecialized dose rate meters placed on aircraft. For methodological support for this approach, an analytical relation is obtained which permits determining indirectly, on the basis of data on the flight altitude, the coefficients which are needed to convert the γ-ray dose rate measured from the aircraft to the value at the ground.

AbstractThe central issue underlying this paper is related to elucidating the hazard of radioactive spallation products that might be an important factor affecting the design option of accelerator-driven systems (ADSs). Hazard analysis based on the concept of Annual Limit on Intake identifies alpha-emitting isotopes of rare earths (REs) (dysprosium, gadolinium, and samarium) as the dominant contributors to the overall toxicity of traditional (W, Pb, Pb-Bi) targets. The matter is addressed from several points of view: code validation to simulate their yields, choice of material for the neutron producing targets, and challenging the beam type. The paper quantitatively determines the domain in which the toxicity of REs exceeds that of polonium activation products broadly discussed now in connection with advertising lead-bismuth technology for the needs of ADSs.

The present paper advertises doping of transplutonium isotopes as an essential measure to improve proliferation-resistance properties and burnup characteristics of UOX fuel for PWR. Among them 241Am might play the decisive role of burnable absorber to reduce the initial reactivity excess while the short-lived nuclides 242Cm and 244Cm decay into even plutonium isotopes, thus increasing the extent of denaturation for primary fissile 239Pu in the course of reactor operation. The doping composition corresponds to one discharged from a current PWR. For definiteness, the case identity is ascribed to atomic percentage of 241Am, and then the other transplutonium nuclide contents follow their ratio as in the PWR discharged fuel. The case of 1 at% doping to 20% enriched uranium oxide fuel shows the potential of achieving the burnup value of 100GWd/tHM with about 20% 238Pu fraction at the end of irradiation. Since so far, americium and curium do not require special proliferation resistance measures, their doping to UOX would assist in introducing nuclear technology in developing countries with simultaneous reduction of accumulated minor actinides stockpiles.

The effect of acetic acid introduced as modifying additive into active aluminum oxide on its structural characteristics is considered. A relationship is established between the structural characteristics, content and features of aprotic acid centers, and catalytic activity of the obtained catalysts in dehydration of methylphenylcarbinol.

We found recently that β-lactamase folds in the yeast cytosol to a native-like, catalytically active, and trypsin-resistant conformation, and is thereafter translocated into the ER and secreted to the medium. Previously, it was thought that pre-folded proteins cannot be translocated. Here we have studied in living yeast cells whether β-lactamase, a tight globule in authentic form, must be unfolded for ER translocation. A β-lactamase mutant (E166A) binds irreversibly benzylpenicillin via Ser70in the active site. We fused E166A to the C terminus of a yeast-derived polypeptide having a post-translational signal peptide. In the presence of benzylpenicillin, the E166A fusion protein was not translocated into the endoplasmic reticulum, whereas translocation of the unmutated variant was not affected. The benzylpenicillin-bound protein adhered to the endoplasmic reticulum membrane, where it prevented translocation of BiP, carboxypeptidase Y, and secretory proteins. Although the 321-amino acid-long N-terminal fusion partner adopts no regular secondary structure and should have no constraints for pore penetration, the benzylpenicillin-bound protein remained fully exposed to the cytosol, maintaining its signal peptide. Our data suggest that the β-lactamase portion must unfold for translocation, that the unfolding machinery is cytosolic, and that unfolding of the remote C-terminal β-lactamase is required for initiation of pore penetration.

The Industrial Association Mayak chose for computations to substantiate the safety of equipment used in radiochemical production processes domestic computer codes, which are as good as the foreign codes but also have an important advantage over the latter – they are tied to the Russian standards. Some of the most typical types of radiochemical industrial equipment in whose design strength calculations were performed using the universal CAN system and the TsIKL code, developed at the ITsP of the Ministry of Atomic Energy, are presented. The computational examples show that the programs indicated make it possible to perform a standardized estimate of the strength of equipment and pipes with any degree of complexity which are used in radiochemical production processes at the Industrial Association Mayak.

Analysis of the radiological burden of the spallation products (SP) was performed for various spallation targets (lead, tungsten, tin). The radiological burden was discussed in terms of toxicity based upon the concept of Annual Limit on Intake (ALI) shows that alpha-emitting rare earths (146Sm, 148Gd, 150Gd, 154Dy) are dominant. Their toxicity was estimated at equilibrium state with and without their transmutation. It is concluded that, in terms of toxicity, accumulation of SP in the target is quite comparable with transmutation of fission products (FP) in the blanket of Accelerator-Driven System (ADS).

The paper presents the advanced concept of a long-life small light water reactor in which the fuel irradiation time is comparable with reactor life-time. The equilibrium analysis reveals that the U-Np-Pu fuel with unique neutronic properties allows to keep sufficient criticality up to burnup value about 140GWd/tHM. The fuel recycle does not lead to additional Pu accumulation. Both Pu and Np are well protected against un-controlled proliferation by a large fraction of 238Pu in their mixture. To improve the reactor safety, the wider fuel pin lattice was applied. The radiation damage of structural materials is within the stainless steel limitation.

Assuming fission reaction as a dominant energy source for a long-term perspective, the goal of transmutation of fission products is to cut their increasing accumulation and to keep their inventories at easily manageable level. Opposite to relatively short-lived 137Cs (T1/2=30yr) whose natural decay converge equilibrium mass to the level of order of 11 per GW of fission energy, an approach to similar equilibrium inventory for long- lived 135Cs (T1/2=2.3×106yr) requires artificial transmutation that preassumes its isotopic separation in the most studies. The present paper addresses cesium transmutation without preliminary isotope separation that means an approach to equilibrium for all the isotopes including stable 133Cs. A high-flux blanket driven by Fusion Neutron Source with ITER-like parameters is proposed to transmute cesium in the elemental form. Transmutation efficiency is estimated in terms of equilibrium inventory and characteristic time to reach equilibrium both governed by the mean life-time of nuclides in transmuter. The analytical results show that the mean life-time of the target isotope 135Cs is as short as 21 yr which is in more than order of magnitude shorter than achieved in advanced fission reactors. It reveals that one Fusion Neutron Source with ITER-like parameters could transmute elemental cesium from 23 PWRs, the fraction of power associated with transmutation being as small as 3%.

Amongst fission products discharged from a fission reactor, mainly iodine and technetium are considered as of primary concern. Their transmutation has been of high priority to reduce the long-term consequences of nuclear energy generation. So far little attention was given to radioactive 93Zr, but its hazard appears to be rather substantial. The importance of 93Zr transmutation is emphasized in the present paper. It is demonstrated that the fusion driven neutron source with high-flux blanket can be applied to transmute 93Zr sufficiently and resolve the problem of its accumulation within the time period of several decades.