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In 2023, it was 130 years since the opening of the Alexander Surgical Hospital at the Tauride Provincial Zemstvo Hospital, where many talented doctors worked. This authors present new facts about outstanding surgeon who worked in Simferopol at the turn of the 19th and 20th centuries, Alexander Fedorovich Kablukov (1857-1915). He was a founder of surgical school in the Tauride province, who first described cholecystectomy In Russian-language literature. The report covers in detail famous surgery restored thanks to pre-revolutionary sources. Excerpts from other little-known reports of surgeon related to the treatment of gallbladder and biliary diseases are also presented.

The non-stoichiometric system Li 0.8 Ni 0.6 Sb 0.4 O 2 is a Li-deficient derivative of the zigzag honeycomb antiferromagnet Li 3 Ni 2 SbO 6 . Structural and magnetic properties of Li 0.8 Ni 0.6 Sb 0.4 O 2 were studied by means of X-ray diffraction, magnetic susceptibility, specific heat, and nuclear magnetic resonance measurements. Powder X-ray diffraction data shows the formation of a new phase, which is Sb-enriched and Li-deficient with respect to the structurally honeycomb-ordered Li 3 Ni 2 SbO 6 . This structural modification manifests in a drastic change of the magnetic properties in comparison to the stoichiometric partner. Bulk static (dc) magnetic susceptibility measurements show an overall antiferromagnetic interaction ( Θ = -4 K) between Ni 2+ spins ( S = 1), while dynamic (ac) susceptibility reveals a transition into a spin glass state at a freezing temperature T SG ~ 8 K. These results were supported by the absence of the λ-anomaly in the specific heat C p (T) down to 2 K. Moreover, combination of the bulk static susceptibility, heat capacity and 7 Li NMR studies indicates a complicated temperature transformation of the magnetic system. We observe a development of a cluster spin glass, where the Ising-like Ni 2+ magnetic moments demonstrate a 2D correlated slow short-range dynamics already at 12 K, whereas the formation of 3D short range static ordered clusters occurs far below the spin-glass freezing temperature at T ~ 4 K as it can be seen from the 7 Li NMR spectrum.

In this work, we focus on silent speech recognition in electroencephalography (EEG) data of healthy individuals to advance brain-computer interface (BCI) development to include people with neurodegeneration and movement and communication difficulties in society. Our dataset was recorded from 270 healthy subjects during silent speech of eight different Russia words (commands): 'forward', 'backward', 'up', 'down', 'help', 'take', 'stop', and 'release', and one pseudoword. We began by demonstrating that silent word distributions can be very close statistically and that there are words describing directed movements that share similar patterns of brain activity. However, after training one individual, we achieved 85% accuracy performing 9 words (including pseudoword) classification and 88% accuracy on binary classification on average. We show that a smaller dataset collected on one participant allows for building a more accurate classifier for a given subject than a larger dataset collected on a group of people. At the same time, we show that the learning outcomes on a limited sample of EEG-data are transferable to the general population. Thus, we demonstrate the possibility of using selected command-words to create an EEG-based input device for people on whom the neural network classifier has not been trained, which is particularly important for people with disabilities.

GdFeTeO 6 and GdGaTeO 6 have been prepared and their structures refined by the Rietveld method. Both are superstructures of the rosiaite type (space group P3¯1c). Their thermodynamic properties have been investigated by means of magnetization M and specific heat C p measurements, evidencing the formation of the long-range antiferromagnetic order at T N = 2.4 K in the former compound and paramagnetic behavior down to 2 K in the latter compound. Large magnetocaloric effect allows considering GdFeTeO 6 for the magnetic refrigeration at liquid hydrogen stage. Density functional theory calculations produce estimations of leading Gd-Gd, Gd-Fe and Fe-Fe interactions suggesting unique chiral 120° magnetic structure of Fe 3+ ( S = 5/2) moments and Gd 3+ ( J = 7/2) moments rotating in opposite directions (clockwise/anticlockwise) within weakly coupled layers of the rosiaite type crystal structure.

An extensive theoretical characterization of the singlet excited state manifold of the five canonical DNA/RNA nucleobases (thymine, cytosine, uracil, adenine and guanine) in gas-phase is carried out with time-dependent density functional theory (TD-DFT) and restricted active space second-order perturbation theory (RASPT2) approaches. Both ground state and excited state absorptions are analyzed and compared between these different theoretical approaches, assessing the performance of the hybrid B3LYP and CAM-B3LYP (long-range corrected) functionals with respect to the RASPT2 reference. By comparing the TD-DFT estimates with our reference for high-lying excited states, we are able to narrow down specific energetic windows where TD-DFT may be safely employed to qualitatively reproduce the excited state absorption (ESA) signals registered in non-linear and time-resolved spectroscopy for monitoring photoinduced phenomena. Our results show a qualitative agreement between the RASPT2 reference and the B3LYP computed ESAs of pyrimidines in the near-IR/Visible spectral probing window while for purines the agreement is limited to the near-IR ESAs, with generally larger discrepancies obtained with the CAM-B3LYP functional. This outcome paves the way for appropriate application of cost-effective TD-DFT approaches to simulate linear and non-linear spectroscopies of realistic multichromophoric DNA/RNA systems with biological and nanotechnological relevance.

MnSnTeO 6 , a new chiral antiferromagnet, was prepared both by topotactic transformation of the metastable rosiaite-type polymorph and by direct synthesis from coprecipitated hydroxides. Its structure and its static and dynamic magnetic properties were studied comprehensively both experimentally (through X-ray and neutron powder diffraction, magnetization, specific heat, dielectric permittivity, and ESR techniques) and theoretically (by means of ab initio density functional theory (DFT) calculations within the spin-polarized generalized gradient approximation). MnSnTeO 6 is isostructural with MnSb 2 O 6 (space group P 321) and does not show any structural transition between 3 and 300 K. The magnetic susceptibility and specific heat exhibit an antiferromagnetic ordering at T N ≈ 9.8 K, which is confirmed by low-temperature neutron data. At the same time, the thermodynamic parameters demonstrate an additional anomaly on the temperature dependences of magnetic susceptibility χ( T ), specific heat C p ( T ) and dielectric permittivity ε( T ) at T * ≈ 4.9 K, which is characterized by significant temperature hysteresis. Clear enhancement of the dielectric permittivity at T * is most likely to reflect the coupling of dielectric and magnetic subsystems leading to development of electric polarization. It was established that the ground state of MnSnTeO 6 is stabilized by seven exchange parameters, and neutron diffraction revealed incommensurate magnetic structure with propagation vector k = (0, 0, 0.183) analogous to that of MnSb 2 O 6 . Ab initio DFT calculations demonstrate that the strongest exchange coupling occurs between planes along diagonals. All exchange parameters are antiferromagnetic and reveal moderate frustration.

A new oxide, sodium-iron antimonate, Na 2 FeSbO 5 , was synthesized and structurally characterized, and its static and dynamic magnetic properties were comprehensively studied both experimentally by dc and ac magnetic susceptibility, magnetization, specific heat, electron spin resonance (ESR) and Mössbauer measurements, and theoretically by density functional calculations. The resulting single-crystal structure ( a = 15.6991(9) Å; b = 5.3323 (4) Å; c = 10.8875(6) Å; S.G. Pbna ) consists of edge-shared SbO 6 octahedral chains, which alternate with vertex-linked, magnetically active FeO 4 tetrahedral chains. The 57 Fe Mössbauer spectra confirmed the presence of high-spin Fe 3+ (3d 5 ) ions in a distorted tetrahedral oxygen coordination. The magnetic susceptibility and specific heat data show the absence of a long-range magnetic ordering in Na 2 FeSbO 5 down to 2 K, but ac magnetic susceptibility unambigously demonstrates spin-glass-type behavior with a unique two-step freezing at T f1 ≈ 80 K and T f2 ≈ 35 K. Magnetic hyperfine splitting of 57 Fe Mössbauer spectra was observed below T * ≈ 104 K ( T f1 < T *). The spectra just below T * ( T f1 < T < T *) exhibit a relaxation behavior caused by critical spin fluctuations, indicating the existence of short-range correlations. The stochastic model of ionic spin relaxation was used to account for the shape of the Mössbauer spectra below the freezing temperature. A complex slow dynamics is further supported by ESR data revealing two different absorption modes presumably related to ordered and disordered segments of spin chains. The data imply a spin-cluster ground state for Na 2 FeSbO 5 .

Background: Ciprofloxacin (CIP) and chloramphenicol (CAP) are relevant antibiotics of the fluoroquinolone (FQ) and amphenicol (AP) groups, respectively, widely used in veterinary practice and they contaminate agricultural products. In this study, a rapid and sensitive immunochromatographic assay (ICA) was developed for simultaneous detection of CIP and CAP in dairy products. The ICA was carried out in a direct competitive format using gold nanoparticles as a label., Results: The ICA developed here allowed for the detection of CIP and CAP in Triton X-100-containing buffered saline (PBST) within 15 min with instrumental detection limits of 20 pg mL -1 and 0.5 ng mL -1 , respectively, and with a visual detection limit of 5 ng mL -1 for both antibiotics. The ICA showed cross-reactivity (69-160%) to 19 antibiotics in the FQ group and no cross-reactivity (<0.1%) to 2 antibiotics of the AP group. The ICA allowed detection of CIP and CAP in a panel of dairy products by employing a simple procedure of preliminary sample preparation. The detection limits for the two antibiotics were the same as in PBST. The analytical recoveries of CIP and CAP in dairy products ranged from 83% to 120%., Conclusion: The analytical characteristics of the test system allow its use for the detection of antibiotics in milk and dairy products during all steps of production. © 2019 Society of Chemical Industry., (© 2019 Society of Chemical Industry.)

The paper analyzes provision of medical interpreting services at border crossing points in the Russian Federation. It is argued in the article that medical interpreting at border crossing points should be viewed as linguacultural mediation in the context close to emergency situations, which requires specific interpreter's competences. The article aims at indenting relevant competences of medical interpreters at border crossing points through conducting an experiment on quality of medical services provision to migrants and refugees in terms of effective interpreter assisted doctor-patient communication. The research methodology rests on cluster, factor and discriminant analysis and integrated two stages: desk and field stages. To conduct the survey part an open-ended questionnaire has been developed which included 7 items. The survey was anonymous and involved native speakers of Arabic, Pashto, Dari, Uzbek, Tajik languages. The conducted research made it possible to identify factors that negatively influenced ultimate assessment of medical services provision at border crossing points. These factors are two-fold: the fists category relates to organizational issues such as lack of specific medicines and doctors with narrow specialization, stressful atmosphere and lengthy border crossing procedure; second category includes linguistic factor such as interpreter's knowledge of communicants' cultural background, ability to act as mediator, goal oriented communicative skills. The research results reveal that medical interpreting at border crossing points should be regarded as intercultural mediation as takes place in unstandardized setting and involves a range of culturally and socially significant issues. As the research outcomes the preliminary list of medical interpreter's competences has been drawn.

Presented herein is experience in treating a total of 56 patients with pathology of the arch, descending and thoracoabdominal aorta from 1997 to 2017. Of these, 6 (11%) patients were diagnosed with a Crawford type I-II thoracoabdominal aortic aneurysm (TAAA), 20 (35%) patients with Crawford type III-IV TAAA, 18 (32%) were diagnosed as having an aortic arch aneurysm (AAA) and descending thoracic aortic aneurysm (DTAA), 12 (22%) had DeBakey type I and IIIb aortic dissection. To protect the visceral organs and spinal cord from ischaemia in 28 (50%) cases we used a temporal bypass from a synthetic vascular graft with zero porosity and measuring from 15 to 20 cm in diameter. RESULTS: Mortality within 30 days amounted to 14.3% (n=8), that after 30 days amounted to 10.7% (n=6): in elective operations - 12% (n=5) and 5.4% (n=3), in emergency operations - 21% (n=3) and 21.4% (n=3), respectively. The total in-hospital mortality amounted to 25% (n=14), equalling 19% (n=8) and 43% (n=6) for elective and emergency operations, respectively. Mortality in using temporal bypass in elective operation amounted to 9.5% (n=2) during 30 days and that without using this method to 14.3% (n=3), after 30 days being 9.5% (n=2) and 4.7% (n=1), respectively. Mortality for emergency cases with a temporal shunt during 30 days was 28.6% (n=2), without - 14.3% (n=1), after 30 days - 28.6% (n=2), without - 14.3% (n=1). In type I-II TAAA mortality within 30 days was 16.6% (n=1), after 30 days - 50% (n=2); type III-IV TAAA - 10% (n=2) and 15% (n=1); DTAA - 22.2% (n=4) and 33.3% (n=2); aortic dissection - 8.3% (n=1) and 16.6% (n=1). Acute renal failure (ARF) occurred in 6 (10.7%) patients and was more often observed in the group without temporal shunting. Events of spinal cord ischaemia with the development of spinal stroke occurred in 6 (10.7%) cases. Five-year survival amounted to 61%. CONCLUSION: Temporal bypass in surgery of the thoracic and thoracoabdominal aorta may be used for prevention of ischaemia of visceral organs, kidneys and spinal cord in operations accompanied by cross-clamping of the descending thoracic aorta.

Ion-exchange treatment of Na2SnTeO6 in molten salt mixtures resulted in rosiaite (PbSb2O6)-related MnSnTeO6. Its crystal structure was refined by the Rietveld method. Of the three possible models of Sn/Te distribution, the disordered model (P3[combining macron]1m, a = 5.23093(11) Å, c = 4.62430(16) Å) was preferred based on bond distances. However, it is supposed that each individual (SnTeO6)2- layer retains complete ordering of the precursor and the apparent disorder is only due to stacking faults. Magnetic studies have shown that MnSnTeO6 orders antiferromagnetically at Neél temperature TN = 9.8 K. The effective magnetic moment reasonably agrees with theoretical estimations assuming high-spin configuration of Mn2+ (S = 5/2). Electron spin resonance reveals spin dynamics in accordance with antiferromagnetic ordering. Moreover, critical broadening of ESR linewidth indicates the low-dimensional type of exchange interactions. Based on the temperature and field-dependent magnetization studies, the magnetic phase diagram of the new compound was constructed.

Accurate characterization of the high-lying excited state manifolds of organic molecules is of fundamental importance for the interpretation of the rich response detected in time-resolved nonlinear electronic spectroscopies. Here, we have characterized the singlet excited state manifold of benzophenone (BP), a versatile organic photoinitiator and a well-known DNA photosensitizer. Benchmarks of various multiconfigurational/multireference (RASSCF/PT2) and time-dependent density functional theory (TD-DFT) approaches allowed assignments of experimental linear absorption signals of BP in the ultraviolet (UV) region, with unprecedented characterization of ground state absorptions in the far UV. Experimental transient absorption spectra obtained by UV-vis pump-probe spectroscopy at very short time delays are shown to be directly comparable to theoretical estimates of excited state absorptions (from the low-lying n O π* and ππ* singlet states) in the Franck-Condon region. Multireference computations provided reliable interpretation of the PP spectra, with TD-DFT results yielding a fair agreement as long as electronic transitions featuring double excitations contributions are not involved. These results lay the groundwork for further computational studies and interpretation of experimental nonlinear electronic spectra of benzophenone in more complex systems, such as BP/DNA adducts.

Benzophenone (BP) despite its relatively simple molecular structure is a paradigmatic sensitizer, featuring both photocatalytic and photobiological effects due to its rather complex photophysical properties. In this contribution we report an original theoretical approach to model realistic, ultra-fast spectroscopy data, which requires describing intra- and intermolecular energy and structural relaxation. In particular we explicitly simulate time-resolved pump-probe spectra using a combination of state-of-the art hybrid quantum mechanics/molecular mechanics dynamics to treat relaxation and vibrational effects. The comparison with experimental transient absorption data demonstrates the efficiency and accuracy of our approach. Furthermore the explicit inclusion of the solvent, water for simulation and methanol for experiment, allows us, despite the inherent different behavior of the two, to underline the role played by the H-bonding relaxation in the first hundreds of femtoseconds after optical excitation. Finally we predict for the first time the two-dimensional electronic spectrum (2DES) of BP taking into account the vibrational effects and hence modelling partially symmetric and asymmetric ultrafast broadening.

Objective: The purpose of the study was to assess surgical outcomes in patients suffering from an infrarenal abdominal aortic aneurysm and treated at the Department of Cardiovascular Surgery #2 of the National Medical Research Centre named after V.A. Almazov., Patients and Methods: We carried out a non-randomized retrospective study including a total of 209 patients presenting with an infrarenal abdominal aortic aneurysm. Of these, 160 (76%) patients were subjected to open surgical interventions (Group One) and 49 (24%) patients underwent endovascular isolation of the abdominal aortic aneurysm (Group Two). The check examination was performed in the early postoperative period and at 30 postoperative days. The mean age of the patients amounted to 65±3.4 and 69±6.2 years in Group One and Two, respectively, with the mean diameter of the infrarenal portion of the aorta amounting to 6.5±0.8 and 6.7±0.9 cm, respectively., Results: 30-day mortality amounted to 2.5 and 2.05% in Group One and Two, respectively (OR 1.231; 95% CI 0.134-11.277). Repeat interventions were more often performed in Group One patients compared with Group Two patients (13.7 vs 2.05%) (OR 6.085; 95% CI 0.791-46.799). Postoperative complications were observed more often in Group One patients than in Group Two patients (OR 9.916; 95% CI 2.143-39.457). Complications encountered in Group One and not observed in Group Two were as follows: nosocomial pneumonia - in 3.75% of cases, acute impairment of cerebral circulation (AICC) and acute myocardial infarction - in 1.25% of cases each, cardiac arrhythmia and acute renal failure - in 1.88% of cases each. Local postoperative wound-related complications were encountered in 18.11% of cases in Group One versus 4.1% in Group Two (OR 5.202; 95% CI 1.195-22.652)., Conclusions: The retrospective analysis of open and endovascular methods of treatment of abdominal aortic aneurysms demonstrated that, given the multifocal nature of an atherosclerotic lesion in the cohort of patients involved, it is appropriate in the preoperative period to perform coronarography in all patients in order to rule out significant damage of the coronary bed. It is also appropriate to regard a cohort over 60 years and patients found to have significant concomitant pathology as candidates for endovascular treatment. A differentiated approach to careful selection will make it possible to improve the results of treatment of abdominal aortic aneurysms.

Both pollution and climate affect insect-plant interactions, but the combined effects of these two abiotic drivers of global change on insect herbivory remain almost unexplored. From 1991 to 2016, we monitored the population densities of 25 species or species groups of insects feeding on mountain birch (Betula pubescens ssp. czerepanovii) in 29 sites and recorded leaf damage by insects in 21 sites in subarctic forests around the nickel-copper smelter at Monchegorsk, north-western Russia. The leaf-eating insects demonstrated variable, and sometimes opposite, responses to pollution-induced forest disturbance and to climate variations. Consequently, we did not discover any general trend in herbivory along the disturbance gradient. Densities of eight species/species groups correlated with environmental disturbance, but these correlations weakened from 1991 to 2016, presumably due to the fivefold decrease in emissions of sulphur dioxide and heavy metals from the smelter. The densities of externally feeding defoliators decreased from 1991 to 2016 and the densities of leafminers increased, while the leaf roller densities remained unchanged. Consequently, no overall temporal trend in the abundance of birch-feeding insects emerged despite a 2-3°C elevation in spring temperatures. Damage to birch leaves by insects decreased during the observation period in heavily disturbed forests, did not change in moderately disturbed forests and tended to increase in pristine forests. The temporal stability of insect-plant interactions, quantified by the inverse of the coefficient of among-year variations of herbivore population densities and of birch foliar damage, showed a negative correlation with forest disturbance. We conclude that climate differently affects insect herbivory in heavily stressed versus pristine forests, and that herbivorous insects demonstrate diverse responses to environmental disturbance and climate variations. This diversity of responses, in combination with the decreased stability of insect-plant interactions, increases the uncertainty in predictions on the impacts of global change on forest damage by insects., (Copyright © 2017 Elsevier B.V. All rights reserved.)

MSb 2 O 6 compounds (M = Mg, Co, Ni, Cu, Zn) are known in the tetragonal trirutile forms, slightly distorted monoclinically with M = Cu due to the Jahn-Teller effect. In this study, using a low-temperature exchange reaction between ilmenite-type NaSbO 3 and molten MSO 4 -KCl (or MgCl 2 -KCl) mixtures, these five compositions were prepared for the first time as trigonal layered rosiaite (PbSb 2 O 6 )-type phases. Upon heating, they irreversibly transform to the known phases via amorphous intermediates, in contrast to previously studied isostructural MnSb 2 O 6 , where the stable phase is structurally related to the metastable phase. The same method was found to be applicable for preparing stable rosiaite-type CdSb 2 O 6 . The formula volumes of the new phases show an excellent correlation with the ionic radii (except for M = Cu, for which a Jahn-Teller distortion is suspected) and are 2-3% larger than those for the known forms although all coordination numbers are the same. The crystal structure of CoSb 2 O 6 was refined via the Rietveld method: P3[combining macron]1m, a = 5.1318(3) Å, and c = 4.5520(3) Å. Compounds with M = Co and Ni antiferromagnetically order at 11 and 15 K, respectively, whereas the copper compound does not show long-range magnetic order down to 1.5 K. A comparison between the magnetic behavior of the metastable and stable polymorphs was carried out. FeSb 2 O 6 could not be prepared because of the 2Fe 2+ + Sb 5+ = 2Fe 3+ + Sb 3+ redox reaction. This electron transfer produces an additional 5s 2 shell for Sb and results in a volume increase. A comparison of the formula volume for the stable mixture FeSbO 4 + 0.5Sb 2 O 4 with that extrapolated for FeSb 2 O 6 predicted that the trirutile-type FeSb 2 O 6 can be stabilized at high pressures.

The authors share herein their experience with hybrid surgical treatment of 21 patients presenting with lesions of the aortic arch and descending thoracic aorta. Aortic pathology included dissection of the thoracoabdominal aorta (n=15), a sacciform aneurysm of the aortic arch (n=5), and a spindle-shaped aneurysm of the distal portions of the aortic arch (n=1). The first stage consisted of the following operations: transposition of the left subclavian artery into the left common carotid artery (n=9; 42.8%), partial debranching (n=11; 52.5%), and total debranching (n=1; 4.7%). The second stage consisted in implantation of a stent graft: to the thoracic aorta in 18 (85.8%) cases, and to the thoracic and abdominal portions of the aorta in 3 (14.2%) cases. The most significant complications of the immediate postoperative period included acute cerebral circulation impairment (n=1) and local dissection of the ascending aorta (n=1). Type I endoleaks were observed in 4 (19%) patients, type II endoleaks in 1 (4.7%), and type III endoleaks in 1 (4.7%). The mean duration of the follow up after discharge from hospital amounted to 11.6±7.9 months. In 4 patients after 6 months the findings of the control MSCT angiography showed no significant changes of the endoleaks. 1-year patency of the shunted branches of the aortic arch amounted to 95.2%. The cumulative survival rate amounted to 95.2%.

Presented herein is a clinical case report regarding hybrid or two-stage surgical treatment of a Crawford type II thoracoabdominal aortic aneurysm in an 87-year-old woman. For the first stage operation we performed open resection of the abdominal aortic aneurysm with aortofemoral bifurcation prosthetic repair and debranching of visceral and renal arteries. Several months thereafter, the second stage operation was performed, consisting in transcatheter exclusion of the thoracoabdominal aortic aneurysm with the help of two stent grafts. The postoperative period turned out uneventful, with no complications. The check-up contrast-enhanced multislice computed tomography (MSCT) carried out 8 months later showed neither endoleaks nor migration of the stent grafts, with the bypass shunts' patency preserved.

A technique was developed for fluorescence polarization immunoassay (FPIA) of ractopamine, a toxic low molecular weight nonsteroidal growth regulator belonging to the most controlled contaminants of food products of animal origin. The assay is based on the competition between a sample containing ractopamine and ractopamine–fluorophore conjugate for binding to antibodies. The competition is monitored via changes in the degree of fluorescence polarization for plane-polarized excitation light, which differs for the free and antibody-bound forms of the conjugate. The optimal assay conditions were established, ensuring a high accuracy and minimal detection limit. The developed assay demonstrated a detection limit of 1 ng/mL and a range of detectable concentrations of 2.3–50 ng/mL, which met the requirements of sanitary control. The duration of the analysis was 10 min. The possible application of the developed FPIA was demonstrated with testing of turkey meat. The speed and simplicity of the proposed assay define its efficiency as a screening tool for safety of foods.

We report the revised crystal structure, static and dynamic magnetic properties of quasi-two dimensional honeycomb-lattice silver delafossite Ag3Co2SbO6. The magnetic susceptibility and specific heat data are consistent with the onset of antiferromagnetic long range order at low temperatures with Néel temperature TN ∼ 21.2 K. In addition, the magnetization curves revealed a field-induced (spin-flop type) transition below TN in moderate magnetic fields. The GGA+U calculations show the importance of the orbital degrees of freedom, which maintain a hierarchy of exchange interaction in the system. The strongest antiferromagnetic exchange coupling was found in the shortest Co-Co pairs and is due to direct and superexchange interaction between the half-filled xz + yz orbitals pointing directly to each other. The other four out of six nearest neighbor exchanges within the cobalt hexagon are suppressed, since for these bonds the active half-filled orbitals turned out to be parallel and do not overlap. The electron spin resonance (ESR) spectra reveal a broad absorption line attributed to the Co(2+) ion in an octahedral coordination with an average effective g-factor g = 2.40 ± 0.05 at room temperature and show strong divergence of the ESR parameters below ∼150 K, which implies an extended region of short-range correlations. Based on the results of magnetic and thermodynamic studies in applied fields, we propose a magnetic phase diagram for the new honeycomb-lattice delafossite.

Characteristics of the fluorescence polarization immunoassay (FPIA) as a mean for express control of antibiotic levels in various specimens and its advantages vs. other analytical tests are described. The developmental stages of the analytical procedure and its parameters are considered for chlorampnenicol as an example. The analysis is based on competitive interaction of anti-chloramphenicol antibodies with the chloramphenicol-fluorophore conjugate and the potential free chloramphenicol in the specimen. The experimental results of the comparison of the chloramphenicol FPIA with the use of two conjugates differing in the length of the bridge length between the antibiotic functional groups and fluorophore (fluorescein) are presented. The requirements to the choice of the antibody and conjugate concentrations providing highly sensitive detection are characterized. The detection limit of chloramphenicol in the FPIA was 10 ng/ml and the determination of the concentrations ranged from 20 ng/mI to 10 mcg/ml. The time of the assay was 10 min.

A rapid immunochromatographic assay was developed for the control of tetracycline (TC). The assay is based on the competition between immobilized TC-protein conjugate and TC in a tested sample for binding with polyclonal anti-TC antibodies conjugated to colloidal gold during the flow of the sample along a membrane strip with immobilized reactants. Conjugation of colloidal gold and the total immunoglobulin (IgG) fraction of polyclonal antibodies was used to increase the assay sensitivity to ensure low content of specific antibodies in the conjugate. This allowed effective inhibition of free TC and conjugate binding in the strip test zone. Photometric marker registration allows control of the reduction of binding, thereby enhancing detection sensitivity. The proposed assay allows TC to be detected at concentrations up to 20 ng/mL, exceeding the limit of detection of the known analogues, in a wide working range (more than two orders) of 60 pg/mL to 10 ng/mL, ensured through the use of polyclonal antibodies. The assay time is 10 min. The efficiency of the designed assay is shown to identify TC in milk; the degree of recovery of TC ranges from 90 to 112%. The precision of the concentrations measurements was no more than 10%.

The enzyme citrate synthase is used by all living cells to catalyze the first step of the citric acid cycle. In this work, we have investigated the enolization and condensation steps catalyzed by citrate synthase, using ab initio (B3LYP/def2-TZVP and MP2/aug-cc-pVDZ) quantum chemical/molecular mechanical hybrid potentials in conjunction with reaction-path-location algorithms and molecular dynamics free energy simulations. The results of the latter indicate that the catalytic His238 residue is in its neutral form, and also argue strongly for the presence of a water molecule in the enzyme's catalytic center. Such a water is observed in some, but not all, of the experimentally resolved structures of the protein. The mechanism itself starts with an enolization that proceeds via an enolate intermediate rather than the enol form, which is much more unstable. This is in agreement with the results of other workers. For the condensation step, we investigated two mechanisms in which there is a direct nucleophilic attack of the enolate intermediate on the oxaloacetate carbonyl carbon, and found the one in which there is no proton transfer from the neighboring arginine to be preferred. Although this residue, Arg329, is not implicated directly in the reaction, it helps to stabilize the negative citryl-CoA formed during the condensation step.

Mixed sodium nickel hydroxide phosphate, Na2Ni3(OH)2(PO4)2, has been synthesized hydrothermally from the system NiCO3-Na4P2O7-NaCl-H2O. Its monoclinic crystal structure has been determined by single crystal X-ray diffraction: a = 14.259(5), b = 5.695(2), c = 4.933(1) Å, β = 104.28(3)°, space group C2/m, Z = 2, ρc = 3.816 g cm(-3), R = 0.026. The underlying spin model has been characterized in terms of first-principles electronic structure calculations. The compound is formed by alternating layers of [NiO6] octahedra and [NaO7] polyhedra, combined in the [100] direction with tetrahedral [PO4] oxocomplexes and hydrogen bonds. The novel phase is treated as an isostructural variant of the two-dimensional potassium manganese hydroxide vanadate, K2Mn3(OH)2(VO4)2, which can be formally obtained by morphotropic substitutions of all positions in the cationic sublattice. The stripe arrangement of Ni(2+) ions (S = 1) within [NiO4(OH)2] layers of Na2Ni3(OH)2(PO4)2 is unique in the sense that its magnetic topology places it in between widely discussed honeycomb and kagomé lattices. The Na2Ni3(OH)2(PO4)2 is a low-dimensional magnet, which reaches the short-range correlation regime at Tmax = 38.4 K and orders antiferromagnetically at TN = 33.4 K.

Structure, electrochemical, magnetic and resonance properties of new layered antimonate Li(4)FeSbO(6) were comprehensively studied using powder X-ray diffraction, cyclic voltammetry, magnetic susceptibility, heat capacity, electron spin resonance and Mössbauer spectroscopy. In the crystal structure the iron ions form the triangular network within (LiFeSbO(6))(3-) layers alternating with nonmagnetic lithium layers. The electrochemical activity studied implies an Fe(3+)/Fe(4+) redox couple at 4.3 V (ox.) and 3.9 V (red.) thereby revealing that Li can be reversibly extracted. The long-range antiferromagnetic order was found to occur at the Néel temperature, T(N) ≈ 3.6 K, confirmed both by the magnetic susceptibility data and specific heat ones. The effective magnetic moment is estimated to be 5.93 μ(B)/f.u. and satisfactorily agrees with theoretical estimations assuming high-spin configuration of Fe(3+) (S = 5/2). In the magnetically ordered state, though, the magnetization demonstrates rather peculiar behavior. An additional anomaly on the M(T) curves appears at T(2) < T(N) in moderate magnetic field. The positions of transitions at T(N) and T(2) separate increasingly with increasing external field. Multiple measurements consistently demonstrated field-sensitive moving of magnetic phase boundaries constituting a unique phase diagram for the compound under study. The complex low-dimensional (2D) nature of magnetic coupling was confirmed by the dynamic magnetic properties study. Electron spin resonance from Fe(3+) ions in paramagnetic phase is characterized by a temperature independent effective g-factor of 1.99 ± 0.01. However, the distortion and broadening of the ESR line were found to take place upon approaching the magnetically ordered state from above. The divergence of the temperature-dependent linewidth is analyzed in terms of both critical behavior close to long-range magnetic order and the Berezinskii-Kosterlitz-Thouless (BKT)-type transition. Heat capacity measurements even at zero field manifested an appearance of the additional anomaly at temperatures below the Néel temperature. The temperature dependence of ESR intensity, linewidth and shift of the resonant field imply an extended region of short-range order correlations in the compound studied. The rich variety of the anomalies in magnetic and resonance properties makes this new antimonate a very interesting system to investigate the multiple phase transitions and competing exchange interaction due to the critical role of the layered structure organization accompanied by the frustration effects in triangular antiferromagnets.

The complex formation of d-metal ions at the interface of Tb(III)-doped silica nanoparticles modified by amino groups is introduced as a route to sensing d-metal ions and some organic molecules. Diverse modes of surface modification (covalent and noncovalent) are used to fix amino groups onto the silica surface. The interfacial binding of d-metal ions and complexes is the reason for the Tb(III)-centered luminescence quenching. The regularities and mechanisms of quenching are estimated for the series of d-metal ions and their complexes with chelating ligands. The obtained results reveal the interfacial binding of Cu(II) ions as the basis of their quantitative determination in the concentration range 0.1-2.5 μM by means of steady-state and time-resolved fluorescence measurements. The variation of chelating ligands results in a significant effect on the quenching regularities due to diverse binding modes (inner or outer sphere) between amino groups at the interface of nanoparticles and Fe(III) ions. The applicability of the steady-state and time-resolved fluorescence measurements to sense both Fe(III) ions and catechols in aqueous solution by means of Tb(III)-doped silica nanoparticles is also introduced., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

An immunochromatographic method for determination of beta-lactam antibiotic ampicillin has been developed. The method is based on the competitive interaction between antibiotic molecules contained in the sample and protein conjugate of penicillin immobilized on a membrane for binding with specific antibodies labeled with colloidal gold, which occurs during movement of the sample to be tested and reagents along the membrane. The completion of the test system ensures control of exceeding the maximum permissible content of the antibiotic in milk and dairy products (10 ng/ml). The possibility of testing milk, raw milk, and dairy products for 10 minutes at room temperature without sample preparation has been demonstrated.

A rapid pretreatment-free immunochromatographic assay was developed for the control of the streptomycin (STR) content in milk and dairy products. The assay is based on the competition between an immobilized STR-protein conjugate and STR in a sample to be tested for the binding to monoclonal anti-STR antibodies conjugated to colloidal gold during the flow of the sample along a membrane strip with immobilized reactants. It is possible to improve the cut-off level of positive and negative samples distinguished by a change in the molar STR to protein ratio in the immobilized conjugate. The cut-off level (500 ng mL(-1)) thus achieved corresponds to the stated MRL of STR in milk and dairy products. For STR concentrations in the range of 16-250 ng mL(-1) its content can be quantitatively measured based on the degree of binding of a colloidal gold label in the test strip zone with the immobilized STR-protein conjugate. The duration of the assay is 10 min. The selected sizes of membrane pores and colloidal gold particles allow the assay to be carried out at room temperature without additional reactants and pretreatment. The applicability of the assay for milk, whole milk, sour clotted milk, and kefir with different fat content (from 0.5% to 6%) was confirmed. The results of quantitative immunochromatographic assay show good correlation with traditional ELISA (r was equal to 0.935 and 0.940 for the series tested)., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Age individuality is characterized by an imbalance of the molecular mechanisms of antioxidant defense in adolescents with arterial hypertension and biliary dyskinesia, as documented by an enzyme imbalance of the first line of antioxidant defense and H2O, accumulation, by a substantial increase in glutathione peroxidase activity, and by inhibition of the activity of glutathione-dependent enzymes. The considerable rise of 2,3-diphosphoglycerate suggests tissue hypoxia. With this, enhanced neutrophil elastase activity causes damage to the structural components of vascular wall connective tissue, resulting in the development of endothelial dysfunction.

A series of new ionic liquids based on sterically hindered decyl(tri-tert-butyl)phosphonium (DTBP) or decyl(tricyclohexyl)phosphonium (DCHP) cations were prepared using quaternisation of tri-tert-butyl- or tricyclohexylphosphine with decylbromide and subsequent bromide exchange with the weakly-coordinating anions BF(4)(-), PF(6)(-), SO(3)CF(3)(-), N(SO(2)CF(3))(2)(-). The salts obtained melt below 100 degrees C and possess a broad electrochemical window. Density functional theory combined with X-ray crystallography, IR and Raman spectroscopy has been used to analyze the molecular and supramolecular structures of the compounds obtained and their possible influence on their physical properties.

A pretreatment-free immunochromatographic assay for detection of chloramphenicol (CAP) in milk was developed. The assay is based on competition between CAP molecules in the sample and immobilized CAP-protein conjugate for binding to monoclonal anti-CAP antibodies conjugated with colloidal gold particles (average diameter 30nm). The assay is carried out in the course of sample flowing along test strip with immobilized reactants, and its results can be detected by the naked eye or by a photometric device. Effect of the concentration of immunoreactants on assay characteristics was studied. The assay protocol with maximal sensitivity and reliability was optimized using measured values of brightness of lines. Detection limit for CAP is 10ngmL(-1). Assay duration is 10min, and it can be carried out at room temperature without any additional devices and reactants. The developed test strip has been applied to CAP detection in dairy products.

The cellulolytic activity of an alkaliphilic obligate anaerobic bacterium, Z-7026, which was isolated from the microbial community of soda-lake sediments and belongs to the cluster III of Clostridia with low G+C content, was studied. The bacterium was capable of growing in media with cellulose or cellobiose as the sole energy sources. Its maximal growth rate on cellobiose (0.042-0.046 h(-1)) was observed at an initial pH value of 8.5-9.0, whereas the maximal rate of cellulase synthesis, assayed by using a novel fluorimetric approach, was found to be 0.1 h(-1) at pH 8-8.5. Secreted proteins revealed high affinity for cellulose and were represented by two major forms of molecular masses of 75 and 84 kDa, whereas the general protein composition of the precipitated and cellulose-bound preparations was similar to cellulosome subunits of Clostridium thermocellum. The optimum pH of the partially purified enzyme preparation towards both amorphous and crystalline cellulose was in the range 6-9, with more than 70% and less than 50% of maximal activity being retained at pH 9.2 and 5.0, respectively.

Larvae of the leaf beetle Chrysomela lapponica derive a defensive secretion from salicyl glucosides found in the host plant Salix borealis. This secretion protects beetle larvae from some natural enemies, but does not appear to repel parasitoids. We tested the hypothesis that the fly parasitoid Megaselia opacicornis (Diptera, Phoridae) uses the larval defensive secretion of Ch. lapponica in its search for prey. In the field, nearly 30 times more M. opacicornis individuals were caught on leaves coated with sticky resin next to a source of secretion than on control leaves. In the laboratory, M. opacicornis females laid six times more eggs next to a cotton ball soaked in secretion than next to one soaked in water. Fly females also lay more eggs on prey rich in larval secretion than on secretion-poor prey. In the field, removal of defensive secretion from beetle prepupae resulted in a 7.5-fold reduction of oviposition by fly females. Parasitoids were nearly twice as likely to lay eggs on prepupae, rich in secretion, as on pupae, which contain little secretion. Fly offspring reared from beetle prepupae reached a 21% larger body mass than those reared from pupae. Finally, M. opacicornis females avoided host prepupae already parasitized by the tachinid fly Cleonice nitidiuscula, which possess little secretion. These experiments indicate that host plant-derived defensive secretions are used by this parasitoid for host location. Adaptation of parasitoids to use defensive secretions of hosts may selectively favor an increase in diet breadth in specialist herbivores.

We compared the general activity and heavy metal resistance of non-specific esterases in two populations of the leaf beetle Chrysomela lapponica from habitats severely contaminated by heavy metals (mostly Ni and Cu) and two populations from unpolluted habitats. Concentrations of Ni and Cu in adult beetles from the most polluted site were 7.7 and 3.6 times higher that in beetles from unpolluted habitats. Larval esterases showed higher activity and lower susceptibility to heavy metals than esterases of adults. Larval esterase activity did not differ between populations from polluted and unpolluted sites, but adult beetles from polluted localities had lower esterase activity than beetles from unpolluted habitats. Both Cu and Ni sulfates in millimolar concentrations in vitro suppressed esterase activity of larvae from unpolluted habitats, but caused no negative effect on esterases of larvae from polluted sites. Similarly, inhibition of adult esterase activity by Ni was stronger in beetles from unpolluted localities than in beetles from polluted localities. This indicates that resistance of non-specific esterases to heavy metals is higher in leaf beetle populations from contaminated environment.

Larvae of the leaf beetle Chrysomela lapponica obtain salicyl glucosides (SGs) from the host plant to produce a defensive secretion with salicylaldehyde. In northern Russia, larvae and pupae experience high parasitism by the phorid fly Megaselia opacicornis and tachinid fly Cleonice nitidiuscula. We compared the suitability of the SG-rich Salix borealis and SG-poor S. caprea and S. phylicifolia to Ch. lapponica and tested whether enemy pressure on Ch. lapponica varies among host species that differ in SG content. In the laboratory, survival of Ch. lapponica larvae was higher on S. borealis than on S. caprea and S. phylicifolia, while adult body mass was higher on S. borealis and S. caprea than on S. phylicifolia. In the field, parasitism by both M. opacicornis and Cl. nitidiuscula was greater on beetles from S. borealis than from the SG-poor S. caprea or S. phylicifolia. In a laboratory choice test, the pupal parasitoid M. opacicornis laid similar numbers of eggs on beetles reared on SG-rich and SG-poor willows, suggesting that the host plant-derived defence is not effective against this parasitoid. In a field enemy-exclusion experiment, beetle survival was greatly enhanced by the exclusion of enemies, but survival rates did not differ between S. borealis and S. caprea, although larvae developed faster on S. borealis. On the other hand, parasitism and predation were observed more often on S. borealis than on S. caprea. Thus, beetle larvae perform better but also suffer higher predation and parasitism on S. borealis than on SG-poor willows. Ch. lapponica does not appear to obtain enemy-free space by feeding on SG-rich willow species.

The relative content of antioxidants in the mycelium of Trichoderma reesei 6/16 obtained by propagation of fungal protoplasts was shown to decrease (as compared to the initial culture taken for preparation of protoplasts) and restored only in the second generation of regenerated mycelium. In this respect, the effects of various antioxidants (beta-carotene, ascorbic acid, alpha-tocopherol, and ionol) on the frequency of regeneration of T. reesei 6/16 protoplasts were studied. beta-Carotene increased the viability of fungal protoplasts to the greatest extent. The effect of ascorbic acid depended on the presence of Fe ions. Ionol did not cause any measurable protective effect.

It has been suggested that the rol genes of Agrobacterium rhizogenes could play an essential role in the activation of secondary metabolite production in plant transformed cultures. This study investigated whether the content of anthraquinone phytoalexins was changed in callus cultures of Rubia cordifolia transgenic for the 35S-rolB and 35S-rolC genes in comparison with a non-transformed callus culture. The anthraquinone content was shown to be significantly increased in transgenic cultures, thus providing further evidence that the rol-gene transformation can be used for the activation of secondary metabolism in plant cells. Methyl jasmonate and salicylic acid strongly increased anthraquinone accumulation in both transgenic and non-transgenic R. cordifolia calluses, whereas ethephon did not. A treatment of the cultures by cantharidin, the protein phosphatase 2A inhibitor, resulted in massive induction of anthraquinone accumulation in the transgenic cultures only. We suggest the involvement of a cantharidin-sensitive protein phosphorylation mechanism in anthraquinone biosynthesis in transgenic cultures.

The fifth abdominal segment of femaleEriocrania semipurpurella (Stephens) andE. sangii (Wood) contains a pair of exocrine glands. Hexane extracts of this segment were prepared from both species and analyzed by gas chromatography with simultaneous flame ionization and electroantennographic detection (EAD). For both species, the EAD active peaks were identified as nonan-2-one, (Z)-6-nonen-2-one, and (Z)-6-nonen-2-ol by means of mass spectrometry and comparison of retention indices with those of synthetic standards. Enantiomeric separation of chiral alcohols from the female extracts was achieved by gas chromatographic analysis on a cyclodextrin column. InE. semipurpurella, a mixture of (2S,6Z)-nonen-2-ol and (2R,6Z)-nonen-2-ol (2: I) was found, whereas inE. sangii (2S,6Z)-nonen-2-ol was the predominant enantiomer and only traces of theR enantiomer were indicated by the antennal response. In field tests, a blend of the three compounds was not attractive to conspecific males. A subtractive assay showed that the alcohol in various enantiomeric mixtures was the only attractive compound, whereas addition of (Z)-6-nonen-2-one to the alcohol completely inhibited the attraction of both species. A trapping experiment including a wide range of ratios between theR andS enantiomers showed that baits containing 95-100% of theS enantiomer were attractive to maleE. sangii, whereas males ofE. semipurpurella were attracted to all tested ratios of the enantiomers. However, the response profiles of maleE. semipurpurella differed between populations from southern Sweden, south Finland, and the Kola Peninsula in Russia. In south Sweden males were maximally attracted to a racemic mixture of the alcohols. At the Kola PeninsulaE. semipurpurella was attracted to baits containing 95-100% of theR enantiomer. In south Finland all tested ratios between 0 and 100%R enantiomer trappedE. semipurpurella, but the trap catches appeared to be bimodally distributed with peaks around 15 and 70%R enantiomer. The trapping results suggest the existence of pheromone races or sibling species among the specimens identified asE. semipurpurella.

Administration of Eleutherococcus to albino rats (18-20-month age) per os daily for 30 days activated the anticoagulating system and protected the animals from thrombogeneration induced with i.v. administration of tissue thromboplastine. The effect of the adaptogen was more obvious after 60-day treatment.

After a single administration (intramuscular or per os) of a complex dicoumarin-heparin into rats its hypocoagulation effect exceeded both in the rate and duration the effect of an equimolar doses of dicoumarin. After an intramuscular administration into rats the complex exhibited the hypocoagulation effect within 55 hrs, dicoumarin--within 31 hr. The hypocoagulation effect of the heparin-dicoumarin complex was maintained within 36 hrs, and the effect of dicumarol--within 14 hrs after administration per os.

Among respiratory syncytial (RS) viruses circulating in the territory of U.S.S.R., strain variations were observed based on the differences in activity of virus reproduction in human embryo kidney cell cultures at 39 degrees C and in virus sensitivity to antibodies. Mathematical expression of the correlation between these two genetic markers made it possible to classify the new isolates of RS virus into three groups differing in their virulence, namely high, mild and low virulent strains. Populations of RS virus strains varied depending on the epidemic season: during the first period (1976-1977) predominated the high virulent (52-78%) while during the second period (1977-1978) the mild virulent (55-65%) strains. The third period (1978-1979) was characterized by the circulation of a mixture of mild and low virulent strains. In summer low virulent virus strains prevailed (56-89%).