Evidence for the formation of two types of oxygen interstitials in neutron-irradiated α-Al2O3 single crystals

Due to unique optical/mechanical properties and significant resistance to harsh radiation environments, corundum (α-Al₂O₃) is considered as a promising candidate material for windows and diagnostics in forthcoming fusion reactors. However, its properties are affected by radiation-induced (predominantly, by fast neutrons) structural defects. In this paper, we analyze thermal stability and recombination kinetics of primary Frenkel defects in anion sublattice − the F-type electronic centers and complementary oxygen interstitials in fast-neutron-irradiated corundum single crystals. Combining precisely measured thermal annealing kinetics for four types of primary radiation defects (neutral and charged Frenkel pairs) and the advanced model of chemical reactions, we have demonstrated for the first time a co-existence of the two types of interstitial defects – neutral O atoms and negatively charged O^- ions (with attributed optical absorption bands peaked at energies of 6.5 eV and 5.6 eV, respectively). From detailed analysis of interrelated kinetics of four oxygen-related defects, we extracted their diffusion parameters (interstitials serve as mobile recombination partners) required for the future prediction of secondary defect-induced reactions and, eventually, material radiation tolerance.

[Traditional nutrition and demography in the Arctic zone of Western Siberia]

High requirements for macro- and micronutrients of the organism of a pregnant woman living in the Far North are associated with the influence of extreme factors of high latitudes, and the needs of the mother and the growing fetus. Only the products of the unique food culture of the Arctic people - the Nenets, make it possible to meet the emerging needs. The aim of the work was to study the impact of traditional nutrition on the reproductive health of Nenets women living in the Arctic zone of Western Siberia. Material and methods. 619 indigenous inhabitants (Nenets) of the Yamal, Nadym and Taz districts of the Yamal-Nenets Autonomous Okrug at the age of 18-65 years were examined. The influence of the type of nutrition (traditional or imported products) on reproductive health indicators (the number of pregnancies, the number of children, the number of spontaneous abortions, frequency of gestosis, threats of termination of pregnancy, operative deliveries) for the period 2013-2018 was studied by analyzing official statistics and by questioning of the female population in own research. Results. The consumption of traditional products (venison, local fishery products, at least 3 times a week) by Nenets women was more often accompanied by a normal physiological course of pregnancy and childbirth (75.2 versus 64.2%, χ²=8.7; p=0.003). It led to a 1.5-fold decrease in the frequency of complications during pregnancy (gestosis, the threat of abortion) (χ²=5.8; p=0.01) and a 20% decrease in the frequency of delivery by cesarean section (χ²=16.6; p<0.001). As a result, a family whose diet was dominated by traditional products had a statistically significantly larger number of children (per child). Conclusion. The preservation of the consumption of reindeer and river fishery products by indigenous women will contribute to the sufficient intake of macro- and micronutrients, that will make it possible to gestate and give birth to a healthier generation of the Nenets society.

Distinctive features of diffusion-controlled radiation defect recombination in stoichiometric magnesium aluminate spinel single crystals and transparent polycrystalline ceramics

MgAl₂O₄ spinel is important optical material for harsh radiation environment and other important applications. The kinetics of thermal annealing of the basic electron (F, F⁺) and hole (V) centers in stoichiometric MgAl₂O₄ spinel irradiated by fast neutrons and protons is analyzed in terms of diffusion-controlled bimolecular reactions. Properties of MgAl₂O₄ single crystals and optical polycrystalline ceramics are compared. It is demonstrated that both transparent ceramics and single crystals, as well as different types of irradiation show qualitatively similar kinetics, but the effective migration energy E_a and pre-exponent D₀ are strongly correlated. Such correlation is discussed in terms of the so-called Meyer-Neldel rule known in chemical kinetics of condensed matter. The results for the irradiated spinel are compared with those for sapphire, MgO and other radiation-resistant materials.

[Autoantibodies to thyroid antigens levels in the population of the Russian Arctic at different levels of blood dopamine.]

Neuroimmunoendocrine regulation of the thyroid gland involves the use of autoantibodies as regulatory molecules to stimulate or reduce the activity of the tissues of the organ itself. A huge number of regulatory signal molecules and factors, acting directly or indirectly, often plays a much more significant role, both in ensuring normal activity and in pathological processes. In this regard, it was interesting for us to determine the possible effect of dopamine at its various concentrations in the blood on the levels of thyroglobulin and antibodies to thyroid antigens. A survey of 110 men and 206 women aged 22 to 75 years who were born and lived in the Arctic zone of the Russian Federation and had no diseases of the endocrine and immune system was conducted. Dopamine concentrations were determined in blood plasma, thyroid stimulating hormone (TSH), thyroglobulin (TG), antibodies to thyroperoxidase (at-TPO) and thyroglobulin (at-TG) in serum. Higher concentrations of thyrotropin and thyroglobulin and lower concentrations of at-TG and at-TPO were shown with increasing dopamine levels from undetectable values to normative and excess levels. We explain this by the influence of dopamine on a-adrenoreceptors of antibody-producing cells and changes in the secretion of immunoglobulins class G, subclasses of which include at-TG and at-TPO. The appearance of different from zero values of autoantibodies concentrations in themselves, we associate with the negative impact of the conditions of the North and the prenosological state of the organism. Their higher values in women with low levels of dopamine can be explained by the lack of its immunomodulatory activity.

[Levels of sex hormones, sex hormone binding globulin, antisperm antibodies and dopamine in postmanopausal women of nomadic and settled aboriginal and local caucasoid populations of the arctic territories.]

Positive changes in the society led to an improvement in quality and lifetime; as a result the menopause in women lengthens much longer, in light of this the relevance of studying hormonal changes increases, especially among the representatives of different groups living in the Arctic territories. The study was carried out on 138 women who included nomadic and settled aboriginal and local Caucasoid postmenopausal populations, permanently residing in the Arctic territories of Russia. The greatest difference in the studied blood indicators was shown between the local Caucasoid and aboriginal population. A greater imbalance in the content of dopamine in Aborigines compared with the European population was combined with a higher levels of prolactin, sex hormone binding globulin, antisperm antibodies and with lower concentrations of lutropine, progesterone, total and free testosterone. In the settled aboriginal population compared with nomadic one there were shown the larger proportion of people with low levels of dopamine, lutropine, follitropin and high levels of prolactin, sex hormone binding globulin in the presence of increased number of feedbacks in the hypothalamic-pituitary-gonadal system, which suggested more pronounced reduction of its activity. The evident imbalance of the dopamine content in the aboriginal population was combined with the absence of connections between dopamine level and the parameters of the hypothalamic-pituitary-gonadal system. Positive correlation between the contents of dopamine and lutropin in the European population suggested the stimulating effect of dopamine on the hypothalamic-pituitary-gonadal system. Affected by imbalanced dopamine content the decreased activity of gonadotropic pituitary gland function as well as the peripheral part of the hypothalamic-pituitary-gonadal system was registered in the aboriginal Arctic population in comparison with the local European one, which was more pronounced in the settled aboriginals.

[THE PREVALENCE OF RESPIRATORY SYMPTOMS AMONG RESIDENTS OF THE RUSSIAN FAR NORTH]

To study the frequency of respiratory symptoms among the reindeer herders of the Yamal region in the Far North of Russia. We conducted a cross-sectional study of the occurrence of respiratory symptoms among 500 subjects of the tundra Nenets population (28.1% of the adult Nenets population in the district), of which 38.3% were men and 61.7% women (average age 40.1 years). All patients were matched for age and occupation. Medical examination was carried out by a pulmonologist with the use of the GARD questionnaire (WHO, 2004) and spirometry. Spirometry was performed with a SpiroUSB device (UK) according to a unified standard and the criteria of ATS/ERS 2005. The frequency of respiratory symptoms among the tundra population was estimated at 71.8%. Cough with expectoration and dyspnea were found in 22.8% of the respondents. 70.0% of the examined subjects worked in the cold, 33% were exposed to the open flame at home, and 34.4% smoked. Respiratory symptoms developed in 16.3% of those working in the cold and in 37% exposed to open fire. The combination of such complaints as cough and sputum production occurred in smokers twice as frequently as in non-smokers (54.1%) (p<0.01).The combination of such complaints as cough and sputum production was twice as likely note in his those who smoked (54.1% vs 20.2%) (p<0.01). The combination of these problems dyspnea was three times more common in the smokers (23,3%vs 7,3%) (p<0.001). At presence at patients of such a factor as work in the cold and the absence of other only 16.3% of them have respiratory symptoms. When using at home the open flame and the absence of other factors leading up 37.0% of the individuals with symptoms of chronic bronchitis. Cough, sputum and dyspnea are formed only among 26.3% of the smokers face when smoking is the only risk factor. If the surveyed residents of all three negative factors respiratory symptoms met at 62.1%. Disorders of respiratory function according to spirometry were not observed in none of the study participants. Respiratory symptoms developed in 62.1% of the subjects exposed to all three risk factors. External respiration indices remain normal in all he examine subjects. It is concluded that residents of the Far North frequently suffer respiratory symptoms without disorders in the external respiratory function. In most cases they associated with three factors (work in the cold, exposure to open fire at home, and smoking). Compensatory stimulation of lung functions may create additional difficulties for diagnostics of bronchial obstruction.

[The content of dopamine and hormones of system "hypophysis - thyroid" in blood of nomadic, settled and local population of the Arctic.]

The examination was applied to the groups of nomadic, settled aboriginal and local Caucasian population of the Arctic, permanently residing in the North. The study was carried out in the same period of the year - the period of increasing of duration of daylight hours. The study covered 253 individuals aged from 21 to 50 years. Despite differences in life-style of nomadic and settled aborigines, the similar signs were established consisting in the higher functional activity of hypophyseal section of the "hypophysis - thyroid" system against the background of lower content of auto-antibodies to thyroid peroxidase under increasing of the level of dopamine in blood as compared with local Caucasian population of the Arctic. The variation of analyzed parameters in aboriginal population depending on life-style also is demonstrated. So, nomadic aboriginal population is characterized by higher content in blood of global and free fractions of triiodothyronine, lower index of peripheral conversion of iodothyronines, increasing of level of dopamine and adenosine mono-phosphate. In case of settled aboriginal population increasing of content of global and free thyroxine is typical. In case of nomadic aborigines an expressed dissonance in content of iodothyronines is established: shifting of limits of variations of global and free triiodothyronine aside of higher bounds of standard at shifting of limits of variations of free fractions of thyroxine aside lower bounds of standard. The positive correlation relationships are registered between content of dopamine, thyroid hormones and adenosine mono-phosphate are registered. They are more expressed nomadic aboriginal population.

Ferroelectricity of domain walls in rare earth iron garnet films

In this paper, we report on electric polarization arising in a vicinity of Bloch-like domain walls in rare-earth iron garnet films. The domain walls generate an intrinsic magnetic field that breaks an antiferroelectric structure formed in the garnets due to an exchange interaction between rare earth and iron sublattices. We explore 180° domain walls whose formation is energetically preferable in the films with perpendicular magnetic anisotropy. Magnetic and electric structures of the 180° quasi-Bloch domain walls have been simulated at various relations between system parameters. Singlet, doublet ground states of rare earth ions and strongly anisotropic rare earth Ising ions have been considered. Our results show that electric polarization appears in rare earth garnet films at Bloch domain walls, and the maximum of magnetic inhomogeneity is not always linked to the maximum of electric polarization. A number of factors including the temperature, the state of the rare earth ion and the type of a wall influence magnetically induced electric polarization. We show that the value of polarization can be enhanced by the shrinking of the Bloch domain wall width, decreasing the temperature, and increasing the deviations of magnetization from the Bloch rotation that are regulated by impacts given by magnetic anisotropies of the films.

Indigenous and tribal peoples' health (The Lancet-Lowitja Institute Global Collaboration): a population study

BACKGROUND

International studies of the health of Indigenous and tribal peoples provide important public health insights. Reliable data are required for the development of policy and health services. Previous studies document poorer outcomes for Indigenous peoples compared with benchmark populations, but have been restricted in their coverage of countries or the range of health indicators. Our objective is to describe the health and social status of Indigenous and tribal peoples relative to benchmark populations from a sample of countries.

METHODS

Collaborators with expertise in Indigenous health data systems were identified for each country. Data were obtained for population, life expectancy at birth, infant mortality, low and high birthweight, maternal mortality, nutritional status, educational attainment, and economic status. Data sources consisted of governmental data, data from non-governmental organisations such as UNICEF, and other research. Absolute and relative differences were calculated.

FINDINGS

Our data (23 countries, 28 populations) provide evidence of poorer health and social outcomes for Indigenous peoples than for non-Indigenous populations. However, this is not uniformly the case, and the size of the rate difference varies. We document poorer outcomes for Indigenous populations for: life expectancy at birth for 16 of 18 populations with a difference greater than 1 year in 15 populations; infant mortality rate for 18 of 19 populations with a rate difference greater than one per 1000 livebirths in 16 populations; maternal mortality in ten populations; low birthweight with the rate difference greater than 2% in three populations; high birthweight with the rate difference greater than 2% in one population; child malnutrition for ten of 16 populations with a difference greater than 10% in five populations; child obesity for eight of 12 populations with a difference greater than 5% in four populations; adult obesity for seven of 13 populations with a difference greater than 10% in four populations; educational attainment for 26 of 27 populations with a difference greater than 1% in 24 populations; and economic status for 15 of 18 populations with a difference greater than 1% in 14 populations.

INTERPRETATION

We systematically collated data across a broader sample of countries and indicators than done in previous studies. Taking into account the UN Sustainable Development Goals, we recommend that national governments develop targeted policy responses to Indigenous health, improving access to health services, and Indigenous data within national surveillance systems.

FUNDING

The Lowitja Institute.

Indigenous and tribal peoples' health (The Lancet-Lowitja Institute Global Collaboration): a population study

BACKGROUND

International studies of the health of Indigenous and tribal peoples provide important public health insights. Reliable data are required for the development of policy and health services. Previous studies document poorer outcomes for Indigenous peoples compared with benchmark populations, but have been restricted in their coverage of countries or the range of health indicators. Our objective is to describe the health and social status of Indigenous and tribal peoples relative to benchmark populations from a sample of countries.

METHODS

Collaborators with expertise in Indigenous health data systems were identified for each country. Data were obtained for population, life expectancy at birth, infant mortality, low and high birthweight, maternal mortality, nutritional status, educational attainment, and economic status. Data sources consisted of governmental data, data from non-governmental organisations such as UNICEF, and other research. Absolute and relative differences were calculated.

FINDINGS

Our data (23 countries, 28 populations) provide evidence of poorer health and social outcomes for Indigenous peoples than for non-Indigenous populations. However, this is not uniformly the case, and the size of the rate difference varies. We document poorer outcomes for Indigenous populations for: life expectancy at birth for 16 of 18 populations with a difference greater than 1 year in 15 populations; infant mortality rate for 18 of 19 populations with a rate difference greater than one per 1000 livebirths in 16 populations; maternal mortality in ten populations; low birthweight with the rate difference greater than 2% in three populations; high birthweight with the rate difference greater than 2% in one population; child malnutrition for ten of 16 populations with a difference greater than 10% in five populations; child obesity for eight of 12 populations with a difference greater than 5% in four populations; adult obesity for seven of 13 populations with a difference greater than 10% in four populations; educational attainment for 26 of 27 populations with a difference greater than 1% in 24 populations; and economic status for 15 of 18 populations with a difference greater than 1% in 14 populations.

INTERPRETATION

We systematically collated data across a broader sample of countries and indicators than done in previous studies. Taking into account the UN Sustainable Development Goals, we recommend that national governments develop targeted policy responses to Indigenous health, improving access to health services, and Indigenous data within national surveillance systems.

FUNDING

The Lowitja Institute.

[Blood free radical oxidation indices in the inhabitants of the Yamal-Nenets Autonomous District]

The paper gives the data of examination of 1333 residents from different areas of the Yamal-Nenets Autonomous District. The examination has demonstrated that oxidative process increase from south to north and from west to east, antioxidative defense becoming weaker.

[Arterial hypertension and risk factors in automobile drivers of Far North]

The authors revealed peculiarities of arterial hypertension in automobile drivers working in Far North and subjected to variety of occupational hazards, so this disease could be considered occupational entity. Facts show that work conditions of automobile drivers in Far North deteriorate course of arterial hypertension and increase importance of risk factors in its prevalence.

[Surgical treatment of hydrocele in elderly and aged patients]

The authors present their personal results of surgical treatment of hydrocele in 163 elderly and senile patients according to modified Alferov's operation. Good long-term results were obtained.

[The pathogenesis of undiagnosed peritonitis in middle-aged and elderly patients with acute coronary insufficiency]

The authors have observed 203 patients at the age of 75-87 with acute coronary insufficiency, 34 patients died on the 6th-8th days of treatment. In 22 of them death was caused by myocardial infarction, in 12--by clinically unrecognized peritonitis. A retrospective analysis of hemostasis was made on admission of the patients to the hospital and on the 5th day of treatment. In the initial state all the patients had the activated system of blood coagulation and the depressed system of anticoagulation. On the 5th day those who later died from peritonitis had had considerably decreased activity of the anticoagulating system of blood. The cause of unrecognized peritonitis in elderly and senile patients with acute coronary insufficiency is thought to be thrombogenesis in microvessels of the intestine.

High temperature radiofrequency transurethral ablation of the prostate (TURAPY)

Conventional treatment for BPH in recent decades has been transurethral resection of the prostate (TURP) or open prostatectomy, depending on adenoma volume. As TURP is a surgical treatment associated with high morbidity, a certain failure rate and mortality, urologists have been looking for other alternative treatments that are safer and at least as effective. Prostatic tissue ablation is one of the preferred alternative BPH treatments today and can be achieved with laser or with TURAPY--Transurethral Ablation Prostatectomy. This new treatment based on thermeablation of the prostate has been introduced recently by Direx Medical Systems. The treatment is administered with a transurethral Folley-like electrode delivering temperatures in the range of 80 degrees C. TURAPY causes extensive ablation of the tissue around the prostatic urethra, without the complications of a surgical procedure. Twenty two men, age 76 to 92 years (mean 79) with symptomatic Benign Prostatic Hyperplasia (BPH) and suprapubuc urinary fistulas were treated with the computer controlled radio frequency device TURAPY as day cases under local anaesthesia. In 1, 5-2 months after the procedure urination was restored, urinary fistulas healed.

Three-dimensional structure of (1-71)bacterioopsin solubilized in methanol/chloroform and SDS micelles determined by 15N-1H heteronuclear NMR spectroscopy

Spatial structures of a chymotryptic fragment C2 (residues 1-71) of bacterioopsin from Halobacterium halobium, solubilized in a mixture of methanol/chloroform (1:1, by vol.) and 0.1 M 2HCO2NH4, or in perdeuterated sodium (2H)dodecyl sulfate (SDS) micelles in the presence of perdeuterated (2,2,2-2H)trifluoroethanol, were determined by two-dimensional and three-dimensional heteronuclear 15N-1H NMR techniques. The influence of (2,2,2-2H)trifluoroethanol on the conformational dynamics of C2 in micelles and the effect of the salt (organic mixture) were studied. Under the best conditions, 1H and 15N resonances of 15N-uniformly enriched protein were assigned in both milieus by homonuclear two-dimensional NOE (NOESY) and two-dimensional total-correlated (TOCSY) spectra and heteronuclear three-dimensional NOESY-multiple-quantum-correlation (HMQC) and TOCSY-HMQC spectra. 651 (organic mixture) and 520 (micelles) interproton-distance constraints, derived from volumes of cross-peaks in two-dimensional NOESY and three-dimensional NOESY-HMQC spectra, along with deuterium exchange rates of amide groups measured in both milieus and 51 HN-C alpha H coupling constants obtained in the case of the organic mixture, were used in the construction of C2 spatial structures. Obtained structures are similar in both milieus and have two right-handed alpha-helical regions stretching from Pro8 to Met32 and Phe42 to Tyr64 (organic mixture), and from Pro8 to Met32 and Ala39 to Leu62 (micelles). In micelles, the second alpha helix is terminated by C-cap Gly63, adopting a conformation characteristic of a left-handed helix. Residues Gly65 to Thr67 from the turn of a right-handed helix. In the isotropic medium of the organic mixture, the C-terminal region of residues 65-71 lacks an ordered structure. Torsion angles chi 1 were unequivocally determined for 18 alpha-helical residues in both milieus. In the isotropic organic mixture and anisotropic micellar system, C2 remains a compact structure with a characteristic size of 3.0-3.5 nm. C2 seems to be present in at least two conformational states, packed and unpacked. Using NMR data, along with the electron cryomicroscopy model of bacteriorhodopsin [Henderson, R., Baldwin, J. M., Ceska, T. A., Zemlin, F., Beckman, E. & Downing, K. H. (1990) J. Mol. Biol. 213, 899-929], we suggested a model for the conformation of C2 in this putative close-packed state. However, no NOE contact between alpha helices was found in either milieu.

[The surgical treatment of malignant tumors of the head of the pancreas and of the periampullary area]

Under analysis are results of pancreatoduodenal resections in 71 patients. In patients with mechanical jaundice lymph drainage with sorption and return of lymph into the vascular bed was used during the preoperative preparation. Occlusion of the duct system of the pancreas stump with glue KL-3 was performed on 62 patients, in 9 patients choledochocholecysto-anastomosis was used in order to improve the quality of the biliodigestive opening. A cryoprocedure on the nonremoved portion of the tumor was performed in 3 cases on the posterolateral surface of the portal vein. These measures allowed the postoperative lethality to be reduced up to 11.2%.

[Treatment tactics for diseases of the scrotal organs in children]

An analysis of results of treatment of 163 children with acute diseases of the scrotum organs for five years has been made. The authors consider that urgent surgery for acute diseases parallel with establishing more precise localization of the process is a good pathogenetic treatment, prevents the appearance of disturbances of all the testicle functions, first of all the spermatogenic function, excludes an obliteration of the deferent duct, considerably shortens staying at the hospital and is not followed by complications.

[Effect of preoperative radiation therapy on intravascular blood coagulation in the combined treatment of kidney cancer patients]

Hemostasis has been studied over time in 137 patients with renal cancer. Of these, 69 underwent surgery only, 68 received combined treatment with preoperative large fractionation radiotherapy. It has been established that renal cancer development in the body stimulates intravascular blood coagulation (IVBC). In the patients with renal cancer who were radiation treated, IVBC activation was more noticeable than in those who had surgery only. To prevent IVBC activation and the development of the DIVC-syndrome, it is proposed to prescribe deaggregates in the period of preoperative therapy and heparin in the postoperative period.

[Mechanism of development of fatal pulmonary artery thromboembolism during the treatment of kidney and bladder cancer]

Retrospective evaluation of the state of hemostasis in 20 patients dying with pulmonary artery thromboembolism (PATE) after combined treatment of renal carcinoma (10) and urinary bladder carcinoma (10) was performed. The signs of intravascular blood coagulation (IVBC) in the initial condition were determined in all the patients. After a course of pre-operation actin therapy with large fractions (totally 20 g) activation of IVBC was observed both in renal and urinary bladder carcinoma. In the postoperation period, on the day of PATE development in patients with renal carcinoma the state of hemostasis corresponded to stage I of disseminated intravascular coagulation syndrome. In patients with urinary bladder carcinoma after operation the state of hemostasis corresponded to stage II of DIVC-syndrome with signs of local hemorrhage of the urinary bladder wound. The therapy of this condition with fibrinolysis inhibitors (aminocaproic acid) with hemotransfusion without heparin facilitated thrombus formation in these patients in deep pelvic veins followed by PATE.

A multinuclear magnetic resonance study of the tetraphenylarsonium and tetraphenylphosphonium tetraphenylborates in nonaqueous solvents

Arsenic-75, phosphorus-31, boron-11, carbon-13 and lH n.m.r. measurements are reported for Ph4As+, Ph4P+ and Ph4B- ions in a number of nonaqueous solvents. The resonance frequencies of the first three nuclei are very nearly independent of the solvent and of the salt concentration indicating an effective shielding of the central atom from the solvent by the four phenyl groups. In contrast the resonance frequencies of the ortho, meta and para carbons and protons of the phenyl rings vary with the solvent. The resonances of the cationic and the anionic carbons and protons are different and the differences are solvent-dependent. The results indicate that the two cations and the anion are solvated to a different extent and that the 'reference electrolyte' assumption, used to obtain single ion transfer activity coefficients, has to be used cautiously.