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The industrial extraction of Y and lanthanides (hereafter defined as Rare Earth Elements, REE) often requires the achievement of leaching procedures removing these metals from primary rocks and their transfer in aqueous leachates or incorporated in newly forming soluble solids. These procedures are the most dangerous to the environment in relation to the composition of leachates. Hence, the recognition of natural settings where these processes currently occur, represents a worthy challenge for learning how to carry out similar industrial procedures under natural and more eco-friendly conditions. Accordingly, the REE distribution was studied in the brine of Dead Sea, a terminal evaporating basin where brines dissolve atmospheric fallout particles and crystallise halite. Our results indicate that the shale-like fractionation of shale-normalised REE patterns in brines, inherited during the dissolution of atmospheric fallout, changes because of the halite crystallisation. This process leads to crystallising halite mainly enriched in elements from Sm to Ho (medium REE, MREE) and coexisting mother brines enriched in La and some other light REE (LREE). We suggest that the dissolution of atmospheric dust in brines corresponds to the REE extraction from primary silicate rocks, whereas halite crystallisation represents the REE transfer into a secondary more soluble deposit with reduced environmental health outcomes.

Diagnosis of the causes of thyrotoxicosis (destruction or increased functional activity of the thyroid tissue in nodular and diffuse thyroid pathology) is a key point in determining the management of patients with this pathology. Scintigraphy is the method of choice in differential diagnosis of the causes of thyrotoxicosis assessing the functional state of the thyroid gland. According to variable medical interest, thyroid scintigraphy can be performed using 99mTc-pertechnetate or radioactive iodine isotopes (123I, 124I, 131I). For thyroid uptake evaluation used scintigraphy with 99mTc-pertechnetate radiopharmaceutical, which is not organificates and quickly excretes from thyroid tissue. In case of thyroid iodine pharmacokinetics investigation radiopharmaceuticals labeled by iodine isotopes (123I,131I, 124I) are used. The review includes original scintigrams, tables and diagrams. Article shows thyroid scintigraphy informativity analysis, evaluates the place and role of the thyroid scintigraphy examinations in modern diagnostic algorithms taking into account the history of the disease, laboratory tests, ultrasound (TIRADS) and result ofFNA (Bethesda). Additionally authors focused on existing clinical guidelines analysis. An optimized algorithm for the diagnosis and treatment of diffuse and/or nodular thyroid pathology associated with thyrotoxicosis is proposed.

Purposes: Current research design is dedicated to 131-I SUV evaluation on post therapeutic scintigrams and setting up predictive model for radioiodine therapy repeated course prescription in differentiated thyroid cancer (DTC). Methods: Study includes 148 patients (f-105, m-43) with DTC treated with 131-iodine. Administered treatment activities of 131I calculated according to clinical features and tumor recurrence risk group. Patients were divided into three groups using ATA 2018 recommendations. Absolute risk groups: low risk (L), medium risk (M), high risk (H). Administered 131-I activity [MBq]: = 3223±729, = 3696±456, = 4589±1078; Tg [ng/ml]: = 7,4±1.7 ng/ml, = 14,8 ±5,9, = 68,3 ±18,5; TgAb [IU/ml]: = 124,3 ± 81.7, = 29,2 ±15,9, = 85,7 ±28,9. All null hypothesis were checked using paired Mann-Whitney U-test. Calibration of system SPECT/CT and evaluation SUVs completed according to protocols designed using Jaszczak phantom Deluxe. Model development based on logistic regression with ROC-analysis, regularization and cross-validation. Results: Reference intervals of SUVpeak and SUVmax calculated for all groups of risk. SUVpeak: low risk >155, medium risk 105-155, high risk 0-105 pL-M=0.069 pL-H=0.0037 pM-H=0.7514; SUVmax: low risk >38, medium risk 29-38, high risk 0-29 pL-M=0.052 pL-H=0.0033 pM-H=0.949. Logit model based on SUVpeak without regularization has: AUC = 0.67 (95%CI 0.33-1.00); Accuracy = 0.82; SE = 0.89; SP = 0.4; PPV = 0.41; NPV = 0.89, cross-validated AUC =0.67 (0.4-0.88), regression coefficients: B0=0.037, B1=0.001. Regularization (SUVpeakConclusion: Study shows that SUV has wide range of values and can be matched with existed model of risk assessment of DTC. Algorithm of image segmentation and evaluation of SUVpeak and SUVmax for SPECT/CT systems was developed. According to the ROC analysis, developed predictive model shows an acceptable performance for further clinical investigation and advancement focused on refining model parameters and introducing additional predictors

RATIONALE: Insufficient world–wide clinical experience in radioiodine therapy (RIT) for Graves’ disease (GD) in children and adolescents, and limited knowledge of the predictors of RIT efficacy.AIMS: Analysis and identification of the most significant predictors of the efficacy of RIT in children and adolescents with Graves’ disease.MATERIALS AND METHODS: A total of 55 patients (48 females and 7 males) aged from 8 to 18 years receiving primary RIT for GD were enrolled. RIT planning was based on the dosimetric method. Analyzed parameters included gender, age, ultrasound thyroid volume before and 6 months after treatment, the presence of endocrine ophthalmopathy, duration of antithyroid drug (ATD) therapy, relapse of thyrotoxicosis after ATD dose reduction, blood fT3, fT4 and TSH levels initially and at 1, 3, 6 months after treatment, TSH receptor Ab initially and at 3 and 6 months after treatment, thyroid 99mTc–pertechnetate uptake at 10–20 minutes (%), maximum thyroid 131I uptake (%), specific 131I uptake (MBq/g) and therapeutic 131I activity (MBq). Fisher exact test, non–parametric Mann–Whitney test, Wilcoxon signed–rank test, logistic regression modelling, ROC–analysis, proportional hazard model (the Cox regression), the Kaplan–Meier method and log–rank test were used for statistical analysis as appropriate.RESULTS: Six months after RIT, hypothyroidism was achieved in 45 (81.8%), euthyroid state – in 2 (3.6%), and in 8 (14.6%) patients thyrotoxicosis persisted. On univariate statistical analysis, the smaller thyroid volume, higher fT4 and lower TSH receptor Ab levels, lower 99mTc–pertechnetate uptake and higher specific 131I uptake were associated with hypothyroidism. On multivariate logistic regression analysis, the older patient’s age (p=0.011), smaller thyroid volume (p=0.003) and higher fT4 (p=0.024) were independent predictors of RIT efficacy. Thyroid volume was also the only variable associated with achievement of hypothyroidism in time after RIT (p=0.011).CONCLUSION: The efficacy of dosimetry–based RIT in children and adolescents with GD 6 months after treatment was 81.2%. Older patients’ age, smaller thyroid volume and higher fT4 level were independent predictors of therapy success. Smaller thyroid volume was also a predictor of the favorable time–related outcome. Statistical models obtained in this work may be used to prospectively estimate the chance of efficient RIT for GD in pediatric patients.

Background. Blood lactate level is often considered as a marker of complex metabolic disorders. Reducing the lactate’s level is a good indicator of therapy adequacy. The purpose: to show the significance of the determination of lactate for predicting the course of the postoperative period in newborns. Materials and methods. 77 infants with abdominal surgical pathology were included in an observational study. Lactate level was measured on admission to the intensive care unit and three times in the first seven days of the postoperative period. Results. ROC-analysis model showed a high predictive value of the indicator at the end of the first postoperative day and on the seventh day. Favorable outсome was connected with lactate ratio below 2.5 mmmol/L on admission, lower than 2.0 mmol/l in the third and seventh days. Point elevation to 3 mmol/l was marked at the end of the first postoperative day. Conclusion. It is advisable to manage a dynamic assessment of lactatemia at the end of the first day and to the end of the third day of the postoperative period.

Biogeochemical processes in northern peatland ecosystems are influenced by seasonal temperature fluctuations that are changing with the climate. Methylmercury (MeHg), commonly produced in peatlands, affects downstream waters; therefore, it is important to understand how temperature transitions affect mercury (Hg) dynamics. We investigated how the freeze-thaw cycle influences belowground peat pore water total Hg (THg), MeHg, and dissolved organic carbon (DOC). Four large, intact peat columns were removed from an ombrotrophic peat bog and experimentally frozen and thawed. Pore water was sampled across seven depths in the peat columns during the freeze-thaw cycle and analyzed for THg, MeHg, and DOC concentrations. Freezing results showed increased concentrations of THg below the ice layers and limited change in MeHg concentrations. During thawing, THg concentrations significantly increased, whereas MeHg concentrations decreased. Limited bromide movement and depth decreases in THg and DOC concentrations were associated with increased bulk density and degree of humification in the peat. The experiment demonstrates the effects of the freeze-thaw cycle on Hg concentrations in northern peatlands. Changes to freeze-thaw cycles with climate change may exacerbate Hg cycling and transport processes in peatland environments.

Existing European standard recommendations for dosimetry examination in case of thyrotoxicosis offers difficult to repeat examination protocols. The individual pharmacokinetics data of 343 patients diagnosed with Graves and Plummer disease and 133 cases with known thyroid volume are presented in the article. The data underwent parametrical statistical analysis. As a result, two clinically reproducible methods of calculating therapeutic activity have been proposed.

Direct parametrical amplification of ultrasound was theoretically considered for the ferromagnetic/piezoelectric thin-layered structure composites, for which within the long-wavelength approach some, material specific, yet homogeneous bulk properties could be assumed. Having chosen appropriate homogeneous components, it is possible to construct a desirable composite with such properties that are absent in the starting-up “building blocks” (components). Sound frequencies are assumed to be such that only the dispersion due to magnetic subsystem is thought relevant; the piezoelectric components are set to have a nonlinear dielectric response. Presence of orientational phase transition for the ferromagnetic subsystem allows to vary frequency of a ferromagnetic resonance, and consequently to alter the dispersion at the chosen frequency of sound. While solving coupled equations describing dynamics of mechanical, magnetic and piezoelectric subsystems, an effective sound amplification for realistic values of physical parameters is shown possible.

Fungal endophytes are one of several groups of heterotrophic organisms that associate with living plants. The net effects of these groups of organisms on each other and ultimately on their host plants depend in part on how they facilitate or antagonize one another. In this study we quantified the associations between endophyte communities and herbivory induced by a biological control in the invasive Lythrum salicaria at various spatial scales using a culture-based approach. We found positive associations between herbivory damage and endophyte isolation frequency and richness at the site level and weak, positive associations at the leaf level. Herbivory damage was more strongly influenced by processes at the site level than were endophyte isolation frequency and community structure, which were influenced by processes at the plant and leaf levels. Furthermore, endophytic taxa found in low herbivory sites were nested subsets of those taxa found at high herbivory sites. Our findings suggest that endophyte communities of L. salicaria are associated with, and potentially facilitated by, biocontrol-induced herbivory. Quantifying the associations between heterotrophic groups ultimately may lead to a clearer understanding of their complex interactions with plants.

The relative change in optical density (orientational turbidimetric effect) of dilute suspensions of bacterial cells is studied theoretically and experimentally. Optical properties of bacterial cells are modeled by homogeneous spheroids using the T-matrix method. Calculated differential spectra of the steady-state turbidimetric effect, as well as its electric field dependence at fixed wavelengths, are shown to be in good agreement with experimental measurements for dilute suspensions of Escherichia coli and Bacillus polymyxa cells. The theoretically predicted unusual non-exponential decay of optical density (after removal of the orienting field) has been illustrated by an experimental electrooptical example. By using the Rayleigh–Debye–Gans approximation, we have also computed orientational effects for dilute suspensions of 3D-lattice ballistic and diffusion-limited fractal aggregates built from optically soft small spheres. We have found that the turbidimetric effect is determined solely by the gyration radius diffraction parameter and is essentially independent of the cluster mass. In terms of orientational effects, the effective structural anisotropy of the random fractal aggregates is close to the anisotropy of the homogeneous spheroidal model with the axial ratio 2 for small clusters and reduces to 1.5 for larger clusters.

In this note we study the homogeneous Riemannian spaces that are closest in a definite sense to symmetric spaces.

Infection with tuberculosis was studied in 3509 adolescents aged 15 years from various social groups via twice BCG revaccination by analyzing the responses to Mantoux tests with 2 TU of tuberculin purified protein derivative and by following them up for 3 years with an annual examination of the same group. The rates of infection among the teenagers was found to be 32.1% and higher (58.5%) in persons without vaccination signs, but with the latter they depend upon the time after BCG vaccination: 0.7% 3 years after the second revaccination, 30.2% after the first revaccination, and 66.8% 15 years following the first vaccination. The timely and qualitative antituberculosis immunization during twice revaccination contributes to reduced infection rates among teenagers.

To determine enzymatic cytolytic activities several methods, based on the change in turbidity of a suspension of microbial cells sensitive to a given enzyme, are in common use. We have developed a method based on the measurement of turbidity spectra with a high-speed turbidimeter and on the algorithms of solution of the inverse spectroturbidimetric problem. The method was evaluated using the bacterium M.lisodeicticus and the enzyme muramidase (lysozyme) as a model system. The cytolytic activity of the lysozyme was examined with a high-speed turbidimeter developed by us, which permits measuring light extinction spectra on 12 discrete wavelengths in the range of 350 to 1000 nm practically simultaneously. This enables the kinetics of change of the light extinction spectra during lysis to be investigated in more detail. In solving the inverse spectroturbidimetric problem we calculated the mean size, number and mass-volume concentrations of M. lisodeicticus in the process of lysis. The activity of the lysozyme correlated well with the rate of change of the disperse particles' mean size in the range from the second to the fifth minute of lysis. We compared the kinetics of change of the disperse particles' mean size in the process of lysis either by the pure lysozyme or by the lysozyme-containing serum. In both cases the process proceeded similarly up to the fifth minute with the activity of the serum being equivalent to the activity of the pure lysozyme in a concentration of up to 1.0 (mu) g/ml.

Particle orientation in a disperse medium results both in anisotropic properties and in the changes in spectral transmittancy. To determine theoretically the effects of such kind a general approach based on the joint use of both the equation of Brownian rotation diffusion and the Mueller matrix for a thin slab of anisotropic medium has been developed. The optical properties of scatterers are described in terms of the first and second Born approximation and the exact T-matrix method. The goal of the investigations is to develop adequate optical models for interpretation of the experimental data obtained for the ordered disperse systems. In this paper, anisotropic properties of oriented disperse systems are discussed in a review manner, while the orientational turbidimetric effect is considered in detail.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Several approaches to increasing the number of parameters of suspended particles that can be determined by a spectroturbidimetric method have been analyzed. It has been shown that, in principle, this problem can be solved invoking spectral characteristics obtained under conditions of complete or partial particle orientation in the stationary and relaxation regimes. Informative potentialities of combining the methods of electro-optics and spectroturbidimetry have been considered. It has been found that eventually for a given disperse system in situ, it is possible to obtain the following set of parameters: particle mean size, shape characteristic and refractive index, number and mass-volume concentration of particles, their total surface area per unit volume of the suspension and the effective value of particle surface polarizability.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A new electrooptic method was used to study the antiplatelet autoimmune process. Antiplatelet antibodies were assessed in 60 patients with idiopathic thrombocytopenic purpura and 60 ones with acquired hemorrhagic thrombocytopathies. The reference group consisted of 50 donors. The relationship between the autoimmune process intensity and the disease severity, as well as blood platelet counts over the course of corticosteroid therapy was studied.

Six patients with gallstone ileus were under observation. The diagnosis was not established before the operation. Surgery was undertaken for acute ileus without identification of the cause. Stones in the intestinal lumen were an unexpected operative finding. The operation of choice was a minimal intervention for the restoration of intestinal continuity (enterolithotomy, resection of the intestine whenever necessary). Five patients recovered, one died.

The sound velocity and attenuation anomalies, connected with the orientational phase transitions (OPT) of first and second order, are investigated for antiferromagnets and ferromagnets. For the first order OPT the anomalies are determined by the motion of the domain walls of the transitional domain structure, while for the second order one they are determined by the interaction of the sound wave and nonequilibrium deviations of the magnetization. The consideration of the influence of the magnetic subsystem on the sound propagation is reduced to the renormalization of the elastic constants. The wave equation and general expressions for the renormalization of the elastic constants, sound velocity, and attenuation are received, taking the magnetostriction and piezomagnetism into account. The comparison of the results received and available experimental data reveals the agreement of the theory and experiments. [Russian Text Ignored]

The interaction of a sound wave and a movable domain structure which appears near orientational phase transitions of the first-order type is considered. The viscous friction is taken into account. The wavelength is considered as being comparable with the domain structure period. The spectrum of magnetoelastic oscillations is calculated, it has a zone character. The evolution of the spectrum branches is investigated when the natural frequency of the domain wall oscillations changes. The attenuation and reflection of sound waves caused by the redistribution of energy between the direct and reverse waves are studied. [Russian Text Ignored]

The static and dynamic properties of a many-domain magnetic with a complicated magnetic phase diagram are considered, the domain walls in the magnetic are fastened with plane defects. Near orientational phase transitions the potential pit of a wall may have a fine structure. It results in the anharmonicity of domain wall oscillations, their spectrum depends strongly on the ratio of anisotropy constants. The temperature dependence of the coercive force, magnetic and magnetoelastic hysteresises, and the dynamic susceptibility are discussed. [Russian Text Ignored]

Magnetic phase diagrams, magnetization curves, and domain structures of a uniaxial two-sub-lattice metamagnet are considered taking into account the magnetostatic energy. The problem of nucleation for a metamagnetic phase transition of the first-order type is investigated. The results are compared with available experimental data. [Russian Text Ignored].

Extensive use is made of anisotropic optical parameters in oriented systems, as in the physical chemistry of colloids [1-3], solutions of synthetic polymers or biopolymers [i, 46], biophysics, and microbiology [7-10] (see reviews [i, ii] for more details). Preference is often given to measurements on dichroism and induced light scattering or transparency change because the instruments are simple. There are numerous papers on the theory of birefringence and light scattering in external fields [i, 11-15], whereas studies on dichroism are extremely few [ii, 12, 16]. A theory has been given [17] for dichroism and birefringence for coarse suspensions of anisotropic particles, which was based on the polarization form of the physical-optics approximation [18]. In [16, 19], some errors in [17] as regards birefringence theory were eliminated. Here we consider a theory of dichroism for the model as in [19], where we examine the dependence on geometrical and optical parameters of the particles and on the ordering. Measurements are reported for the electrooptic effect in aqueous suspensions of yeast and bacterial cells.

The attenuation of the electromagnetic and sound waves interacting with a transitional domain structure in the neighbourhood of orientational phase transitions of the first-order type is calculated. It is taken into account that the domain wall displacement under wave action is irreversible, i.e. the magnetoelastic or magnetic hysteresis occurs. It is shown that in the general case contributions of reversible and irreversible domain wall displacements into the wave attentuation are not additive. [Russian Text Ignored].

A Green's-function method is used to calculate the shape of the magnetophonon-oscillation line of the differential susceptibility of a semiconductor in a quantizing magnetic field. The amplitude of the resonant peak is shown to be proportional to g2/3 (where g is the electron-phonon interaction constant), while the peak width is proportional to g4/3.

CONTENTS ForewordChapter I. Introduction § 1. Linear Lie groups § 2. Semisimple Lie groups § 3. Symmetric riemannian spacesChapter II. The fundamental theorems § 4. Statement of the fundamental theorems § 5. Proof of the algebra decomposition theorem § 6. Properties of the Cartan decomposition of a simple algebra § 7. Proof of the decomposition theorem for groups with trivial centre § 8. The symmetric riemannian space . Proof of the conjugacy theorem for groups with trivial centre § 9. The general caseChapter III. The centres of the noncompact real semisimple Lie groups and the kernels of their linear representations § 10. Introductory material § 11. The canonical form of an involutory automorphism and the enumeration of the real forms of the complex simple algebras § 12. The centre of a real semisimple group § 13. Formulae for the centres of the simply-connected non-compact simple Lie groups § 14. Another method of finding the centres § 15. Linear real semisimple groups § 16. Linearizers and kernels of linear representations § 17. Formulae for linearizers and kernels of linear representationsReferences

The possible magnetic states of orthorhombic weak ferromagnets and rare-earth orthoferrites (REOF), the change of the magnetic state with the change of the temperature, and the mechanism of the formation of a new magnetic phase nucleus from a 180° domain wall for the first-order phase transition are considered. The ΔE-effect for both the first order phase transition and the transition by the reversible rotation of the antiferromagnetic vector and the magnetic susceptibility tensor, connected with the displacement of 90° domain walls, are calculated. [Russian Text Ignored].