Application of HRGS for forensic characterization of uranium oxides, pure uranium metals and uranium alloys.

A nondestructive iterative method for uranium-bearing material characterization with HRGS developed earlier in Burdeinyi et al. (2020) is applied to determine matrix densities, uranium mass fraction and uranium isotope masses of uranium ore, UO2 and U3O8 powders, fuel elements in the form of UO2 microspheres, uranium metal and uranium alloys. It is shown that U3O8 powders with uranium mass fraction of about 84% can be distinguished from the powders of UO2 with uranium mass fraction of about 87%; uranium products in the form of liquid or loose powder with matrix density of 0.5-2.0g/cm3 can be distinguished from uranium products in the form of compacted fuel elements with matrix density of 6.0-10.0g/cm3 and from pure metal uranium and uranium alloys with matrix density of 14.0-19.0g/cm3. In fuel microspheres based on UO2 the uranium mass fraction 88.02% measured by HRGS is consistent, within the measurement uncertainties, with the results of isotope dilution mass spectrometry 87.76±0.64% and also is confirmed by X-ray diffraction technique. The uranium mass fraction of the uranium ore estimated as 0.08% by HRGS is consistent, within the measurement uncertainties, with the value 0.09±0.01% determined with WDXRF. Densities of two different uranium metal samples, estimated as 18.42g/cm3 and 19.33g/cm3 by HRGS are consistent with values 18.24±0.55g/cm3 and 18.86±0.59g/cm3, respectively, obtained by the gas pycnometry technique.

A new nondestructive iterative method for forensics characterization of uranium-bearing materials by HRGS.

In addition to the isotopic composition of a radioactive material, the high-resolution gamma spectrometry (HRGS) allows one to quantify physical characteristics of the material, which are important for nuclear forensics. A quantitative assessment of these characteristics requires two input parameters: the sample density and the mass fraction of radioactive material in the matrix. A method is proposed to determine these parameters provided that the enrichment and the total mass of the material are known. The method is formulated as an iterative quasi-Newton Broyden algorithm for finding roots of two functions in two variables. The developed method is applied to certified reference materials based on the powder uranium octaoxide in the range of enrichments from 0.3% to 93%. It is shown that the matrix density and the uranium mass fraction found experimentally well agree with the declared data in certificates, and the deviations do not exceed 4% up to an enrichment value of 93%.

[Knee joint instability: the current view of the problem]. / Nestabil'nist' kolinnoho suhloba: suchasnyi pohliad na problemu.

Modern instrumental methods of diagnosis of the knee joint (KJ) fracture and of the damaged structures identification are presented. The proposed modern methods of operative treatment of the KJ posttraumatic instability, which are applied in the clinic, are recommended for broad usage.

[Fracture of the femoral neck and osteoporosis]. / Perelom shyiki stehnovoï kistky i osteoporoz.

The authors have established that osteoporosis is noted in the age above 70 years old--in 70-80% and above 80 years old--in all of the patients. That's why while treating the fractures of neck of the femur (NF) in the patients aged older than 60 years the osteosynthesis is not recommended. The stump joint endoprosthesis may be a method of choice. It is expedient to prescribe antiresorptive preparations phosamax, myacalcique and preparations of calcium in the complex of treatment.

[Systemic enzyme therapy in orthopedics and traumatology]. / Systemna enzymoterapiia v ortopediï i travmatolohiï.

In 57 patients the preparations of systemic enzyme therapy vobenzim and flogenzim were applied during conservative or operative treatment of locomotor system injuries. Anti-edema, antiinflammatory and analgetic action of preparations was established.

[Total endoprosthesis of the knee joint]. / Total'ne endoprotezuvannia kolinnoho suhloba.

The results of conduction of 7 operations endoprosthetics of the knee joint using AGC-system of the "Biomet" concern are adduced. Details of operative procedure are enlightened, clinical cases and immediate results of operation are adduced.

[Prevention of suppurative inflammatory complications in traumatology]. / Profilaktika gnoino-vospalitelhykh oslozhnenii v travmatologii.

On the basis of the data of clinical, bacteriologic, immunologic investigations, the system for prevention of purulent-inflammatory complications (PIC) in treatment of closed and open fractures of the extremities has been developed. Use in the clinic of a system for prophylaxis permitted to reduce the incidence of PIC development in operative treatment of closed fractures from 5.6 to 1.64%, after performance of the emergency operations for open injuries--from 18.3 to 5.4%.

[Deforming gonarthrosis (questions of pathogenesis)]. / Deformiruiushchii gonartroz (nekotorye voprosy patogeneza).

Based on the biochemical, morphological, radionuclide, electron microscopy and arthroscopic data it has been established that there are significant changes in collagen proteins of the joint cartilage in the first stage of gonarthrosis deformans when degenerative and dystrophic alterations can only be seen in the joint cartilage. The determination of type II collagen which is commonly called procollagen brings something new in the understanding of the mechanism of degenerative dystrophic alterations in the joint cartilage. A considerable increase of a local proteolytic activity has been ascertained, which should be considered as the result of deep redox processes in the cartilage tissue. Gonarthrosis-associated microcirculatory disorders in the epiphyses with the development of vascular stasis, thrombosis, mural and total erythrocyte microaggregation cells, and perivascular hemorrhages have been confirmed. For the first time two forms of gonarthrosis (acute and latent) have been defined arthroscopically. The pathogenetic treatment methods have been elaborated in terms of the stages of the morphological changes identified.

[Changes in the synovial medium in deforming gonarthrosis]. / Izmeneniia sinovial'noi sredy pri deformiruiushchem gonarthroze.

The authors have determined the changes in the synovial medium of the joint characteristic of various stages of severity of the disease in 248 patients with deforming gonarthrosis on the basis of arthroscopic and thermographic studies and investigation of the permeability of the synovial membrane in the complex with clinical and roentgenologic examinations. At the initial stages the signs of local reactive inflammation of the synovial membrane near the foci of degeneration of the articular cartilage prevail. For the late stages a trend to spreading of the reactive inflammation of the synovial membrane with the development of sclerotic changes in the previously affected areas is characteristic. A comparison of the results of arthroscopy, infra-red thermography and the permeability of the synovial membrane point at parallel changes in the synovial medium and in the microcirculatory and regional circulation of the knee joint. These findings may be used for working out the rational tactics of treatment of the patients with deforming gonarthrosis.

[Osteotomy in the complex treatment of coxarthrosis]. / Osteotomiia v komplekse lecheniia koksartroza.

The author presents the substantiation of the use of intertrochanteric osteotomy of the femur in 174 patients with coxarthrosis. On the basis of clinical, roentgenologic and biomechanical data two basic operations are recommended: Pauwels-I and Bombelli, which together with various supplements depending on the stage, the form, the age and other peculiarities bring stable positive results within 10 and more years.

[Clinical, x-ray and arthroscopic parallels in initial stages of deforming arthrosis of the knee joint]. / Kliniko-rentgeno-artroskopicheskie paralleli pri nachal'nykh formakh deformiruiushchego artroza kolennogo sustava.

The study is based on the results of a clinical, roentgenologic and arthroscopic examination of 166 patients at the early stages of development of deforming arthrosis of the knee joint. The peculiarities of the early clinical, roentgenologic and arthroscopic symptoms and their relationship with the causative factors of the development of the disease have been investigated. The parallels between clinical and roentgenologic manifestations have been determined with regard to the degree of the degree of the degenerative and dystrophic changes in the articular cartilage, which is of major importance for the early diagnosis and the development of rational treatment of this pathologic condition.

[Functional anatomy, diagnosis and treatment of chronic instability of the knee joint]. / Funktsional'naia anatomiia, diagnostika i lechenie khronicheskoi nestabil'nosti kolennogo sustava.

On the basis of results of anatomical experimental, biomechanical investigations and 285 clinical observations, a new approach to the understanding of the problem of instability of the knee joint is suggested. It was proved, that instability of a joint developed in damage to a number of its structures. A classification of the anteromedial and anterolateral instability has been developed.