Metal-organic frameworks as competitive materials for non-linear optics.

The last five years have witnessed a huge breakthrough in the creation and the study of the properties of a new class of compounds - metamaterials. The next stage of this technological revolution will be the development of active, controllable, and non-linear metamaterials, surpassing natural media as platforms for optical data processing and quantum information applications. However, scientists are constantly faced with the need to find new methods that can ensure the formation of quantum and non-linear metamaterials with higher resolution. One such method of producing metamaterials in the future, which will provide scalability and availability, is chemical synthesis. Meanwhile, the chemical synthesis of organized 3D structures with a period of a few nanometers and a size of up to a few millimeters is not an easy task and is yet to be resolved. The most promising avenue seems to be the use of highly porous structures based on metal-organic frameworks that have demonstrated their unique properties in the field of non-linear optics (NLO) over the past three years. Thus, the aim of this review is to examine current progress and the possibilities of using metal-organic frameworks in the field of non-linear optics as chemically obtained metamaterials of the future. The review begins by presenting the theoretical principles of physical phenomena represented by mathematical descriptions for clarity. Major attention is paid to the second harmonic generation (SHG) effect. In this section we compare inorganic single crystals, which are most commonly used to study the effect in question, to organic materials, which also possess the required properties. Based on these data, we present a rationale for the possibility of studying the non-linear optical properties of metal-organic structures as well as describing the use of synthetic approaches and the difficulties associated with them. The second part of the review explicitly acquaints the reader with a new class of materials which successfully combines the positive properties of organic and inorganic materials. Using recently synthesized metal-organic frameworks and coordination polymers in the field of non-linear optics as an example, we consider synthetic approaches used for obtaining materials with desired properties and the factors to be considered in this case. Finally, probable trends towards improving the quality of the synthesized materials with regards to their further use in the field of non-linear optical effects are described.

[Replacement plastic reconstruction of extended ureteral stricture using buccal mucosa autograft].

The potentials for the use of free buccal mucosa graft in reconstruction plastic surgery of extended uretral stricture are evaluated. From 2007 to 2013, 9 operations in 8 patients (mean age 54,5+/-7,2 years) were performed. The average length of cicatricial uretral stricture was 5,1+/-0,7 cm. 1 patient has lesion in the upper third of the ureter, 4 patients - in the middle portion, and 4 patients - at the bottom portion. The causes of extended uretral stricture were following: long standing calculi (n=3), ureteral injury after ureterolithotripsy (n=2) and after bringing down the calcuus using loop (n=1), radiotherapy (n=3, one patient had bilateral injury). All patients underwent plastic reconstruction of ureter using buccal mucosa graft by "on-lay" type. During the follow-up (median, 42 months, from 3 to 72 months), in 7 (88,9 %) of 8 patients (8 operations) ureteral strictures relapses were not observed. They all had satisfactory renal excretory function without the pronounced violations of passage of urine along the ureter. The excretory urography showed moderate expansion of the ureter at the site of operation in 6 of them. Due to the progression of secondary renal scarring, one patient underwent nephrectomy 1.5 year after reconstruction plastic surgery. In this patient, pronounced anatomical and functional changes in the kidney occurred before the operation. Application of the buccal mucosa graft in reconstruction plastic surgery in extended uretral stricture is high effective due to the relatively low level of early and late postoperative complications and low recurrence rate.

Mössbauer spectroscopy of the iron cores in human liver ferritin, ferritin in normal human spleen and ferritin in spleen from patient with primary myelofibrosis: preliminary results of comparative analysis.

Comparative study of human liver ferritin and spleen tissues from healthy human and patient with primary myelofibrosis was carried out using Mössbauer spectroscopy with a high velocity resolution at 295 and 90 K and with a low velocity resolution at 20 K. The results obtained demonstrated that the iron content in patient's spleen in the form of iron storage proteins was about ten times larger than that in normal tissue. However, in the case of patient with primary myelofibrosis the magnetic anisotropy energy barrier differed from that in normal case and, probably, the iron core size was supposed to be slightly larger than that in both normal spleen tissue and normal human liver ferritin in contrast to well-known data for iron overload in patients with thalassemia accompanied by the iron-core size increase. Therefore, the iron overload in the case of patient with primary myelofibrosis may be related to increase in the ferritin content mainly. It was also found that Mössbauer hyperfine parameters for normal and patient's spleen and normal human liver ferritin demonstrated some small differences related, probably, to some small structural variations in the ferritin iron cores of patient's spleen.

Heme iron state in various oxyhemoglobins probed using Mössbauer spectroscopy with a high velocity resolution.

A comparative study of oxyhemoglobins from pig, rabbit, normal human and patients with blood system malignant diseases was performed using Mössbauer spectroscopy with a high velocity resolution at 90 K. Mössbauer spectra were fitted with the help of two models: using one quadrupole doublet (model of equivalent iron electronic structure in α- and ß-subunits of hemoglobins) and superposition of two quadrupole doublets (model of non-equivalent iron electronic structure in α- and ß-subunits of hemoglobins). The results obtained using both models demonstrated small variations of hyperfine parameters that were related to the heme iron state variation in different hemoglobins. These results were compared with structural and functional differences of the hemoglobins investigated.

Dialectic Unity of the Domestic and Foreign Policy of China On the Centenary of the Communist Party of China.

This July marks the 100th anniversary of the founding of the Chinese Communist Party. This event motivated the authors of this article to consider the main problems that modern Chinese society is solving, the place of the PRC in the world economy and politics at the beginning of the third decade of the 21st century, and China's growing influence on the planet. China's undoubted successes, including in the fight against the coronavirus pandemic and in overcoming the recession caused by tough quarantine measures in early 2020, show the considerable viability of the state created by the Chinese communists, which is increasingly at the forefront of the world in the economy, science and technology, and culture. However, the path to the current rise of the great power was by no means an easy one, and the prospects for its development are perhaps one of the most debated issues in international discussions. China never tires of emphasizing the specifics of its history. At the same time, the diversity of the internal conditions of the colossal country together with the skillful application of carefully studied foreign experience yielded the extraordinary wealth of forms of development, which can serve as a guarantee of new achievements and, possibly, useful universals for all humankind.

Effect of Sol-Gel Alumina Biocomposite on the Viability and Morphology of Dermal Human Fibroblast Cells.

This paper is the continuation of our previous work on the ability of biocomposites based on sol-gel alumina (boehmite) to promote skin recovery from burns and atrophic scars. The present study describes the increasing of the cytoplasma volume and the number of filopodias of HDF cells, which for the first time indicates their proliferation on the alumina itself and on alumina-based biocomposite. Studies in vivo confirm the efficiency of the composite in the treatment of atrophic scars.

Submicrosecond regular and chaotic nonlinear dynamics in a pulsed picosecond Nd:YAG laser with millisecond pumping.

We propose and study both numerically and experimentally a feedback-controlled laser system capable of generating regular bursts with a submicrosecond period. Bursting is obtained in a laser that is controlled by a combination of feedbacks in which the negative feedback loop action is delayed by one cavity round trip with respect to the positive one, and the period is adjusted by relative feedback sensitivity. The proper combination of feedbacks is realized in a Nd:YAG laser with millisecond pumping by means of a single optoelectronic negative feedback unit that utilizes the signal reflected from an intracavity Pockels cell polarizer. Regular bursting (microgroups of picosecond pulses) with controlled periods from 25 to 75 cavity round trips is obtained experimentally. The development of chaotic dynamics displayed by the system at a higher pumping level differs from the Feigenbaum scenario.

The Iron State in Spleen and Liver Tissues from Patients with Hematological Malignancies Studied Using Magnetization Measurements and Mössbauer Spectroscopy.

In this overview, we present the results of the study of spleen and liver tissues taken from healthy donors in comparison with those from patients with (i) non-Hodgkin B-cell lymphomas, namely, mantle cell lymphoma and marginal zone B-cell lymphoma, (ii) acute myeloid leukemia, and (iii) primary myelofibrosis. The study was carried out using Mössbauer spectroscopy and magnetization measurements for the analysis of ferritin-like iron in spleen and liver tissues. Magnetization measurements demonstrated small differences in the saturation magnetic moments and revealed additional paramagnetic components. Two liver samples demonstrated unusual behavior of the magnetic moment when the zero-field-cooled curve was over the field-cooled curve in the temperature range between ~40 and ~70 K. Relative iron content variations in the tissue cells as well as small variations in the 57Fe hyperfine parameters were demonstrated for healthy and patients' spleen and liver tissues on the base of measured Mössbauer spectra. The results obtained permit us to suggest small differences in the ferritin iron core structure in spleen and liver tissues from healthy donors and patients with hematological malignancies.

[Corporative culture of stomatological institution appraisal by the questionnaire method].

Multiple processes in economics reflect in management and corporative culture of any institution. Long-term motivational influence plays main role in the motivation mechanism; in turn motives form stable and long-term acting system integrated into corporative culture of any stomatological institution. Integration of the interests of the institution and separate members of the staff becomes the basic condition of the interested attitude to work.

Unique anisotropic optical properties of a highly stable metal-organic framework based on trinuclear iron(iii) secondary building units linked by tetracarboxylic linkers with an anthracene core.

A highly stable metal-organic framework, [{Fe3(ACTBA)2}X·6DEF]n (1; X = monoanion), based on trinuclear iron(iii) secondary building units connected by tetracarboxylates with an anthracene core, 2,6,9,10-tetrakis(p-carboxylatophenyl)anthracene (ACTBA), is reported. Depending on the direction of light polarisation, crystals of 1 exhibit anisotropic optical properties with birefringence Δn = 0.3 (λ = 590 nm).

Quantitative analysis of bone mineral content by x-ray microtomography.

A new non-destructive method based on x-ray microtomography (micro-CT) was developed to measure calcium density in bone. X-ray micro-CT was used as a quantitative approach to acquire and reconstruct virtual cross-sections through the sample. Accurate beam-hardening correction was implemented. Grey values in the virtual cross-sections were calibrated as calcium mineral density in bone. From these cross-sections, three-dimensional models were created. Calcium content was calculated directly from images and expressed as percentage per volume and per weight. Calcium mineral density was studied by this method in a unique set of bones isolated from newts (Pleurodeles waltlii Michah) that had travelled into space. A demineralization of 10% was shown as a consequence of sustained micro-gravity.

[Detection and functional role of local gradients of H+-ions on the intracellular mitochondrial membrane with covalently linked pH-probe]. / Obnaruzhenie i funktsional'naia rol' lokal'nykh gradientov H+-ionov na vnutrennei membrane mitokhondrii s kovalentno prisoedinennym H-zondom.

The study is devoted to the registration of local H+ gradients on the inner membrane of mitochondria under conditions of H+ pump functioning were recorded. By using a covalently linked pH probe (fluorescein isothiocyanate), a local increase in the activity of hydrogen ions on the outer face of the inner mitochondrial membrane in the presence of the respiration substrate at increased permeability of the membrane for K+ was registered. It was also found that the buffer capacity of medium affects the respiration rate of completely uncoupled mitochondria; a change in respiration rate strictly correlates with changes in local H+ gradients on the mitochondrial membrane. It was concluded that local gradients of H+ activity can control the rate of functioning of H+ pumps. It was shown that, under certain conditions, the system of H+ pumps incorporated into succinate oxidase of mitochondria functions as a nonliner system.

[Differences in ways of development of myocardial infarct with severe and mild clinical course]. / Razlichie sposobov formirovaniia infarkta miokarda tezhelogo i legkogo klinicheskogo techeniia.

In 43 dead and 83 survived patients with myocardial infarction, the severity of the disease was compared with hourly changes in indications of a precordial cardiogram made in the first 2 days. The signs were defined, which made it possible to predict a relapse of myocardial infarction 10-15 hours before its onset. The rate of transformation of myocardial lesion foci to necrosis was found to affect the lifespan of patients. The end mass of myocardial infarction was shown to be formed via confluence of individual necrotic foci which appear in the myocardium at various intervals. The early signs were described, which enabled severe cases of myocardial infarction, resulting in death to be differentiated from those leading to a patient's recovery.

[Digoxin therapy of chronic cardiac failure under control of its concentration in the blood]. / Terapiia khronicheskoi serdechnoi nedostatochnosti digoksinom pod kontrolem kontsentratsii ego v krovi.

The influence of digoxin concentration in blood on its therapeutic effect was studied in 59 patients with chronic circulatory insufficiency and cardiac fibrillation and in 89 patients with chronic circulatory insufficiency and sinus cardiac rhythm. The changes in blood digoxin concentration in patients with cardiac insufficiency complicated by cardiac fibrillation with maintained sinus cardiac rhythm both during the "saturation" period and during maintenance treatment were of the same type. The content of digoxin in the blood does not determine the potency of its therapeutic effect. The optimum therapeutic effect of digoxin in all patients with cardiac fibrillation and signs of cardiac insufficiency persists for quite a long period of time. Continuously used cardiac glycosides lose their inotropic effect in patients with sinus cardiac rhythm.

[Hepatic function in circulatory insufficiency. Mathematical modeling of 137I-labelled rose bengal transport in the body]. / Funktsiia pecheni pri nedostatochnosti krovoobrashcheniia. Matematicheskoe modelirovanie transporta bengal'skogo rozovogo-137I v organizme.

131I-labelled bengali pink was used to perform radiohepatography in patients with circulatory failure. Both amplitude-time parameters of blood clearance curves and hepatograms and the generalized index of parameters of the linear 3-chambered reversible model of this tracer transport in the body indicate that the decrease of hepatic absorptive and excretory function in the presence of 131I-labelled bengali pink occurs in a direct relationship to the degree of circulatory insufficiency and developed in parallel with bilirubin metabolic disturbances. In some patients, hepatic lesion in the presence of Stages IIB-III circulatory insufficiency with signs of hepatocellular failure and cholestasis was accompanied only by moderate hepatic absorptive and excretory dysfunction against 131I-labelled bengali pink and by an increase in blood total bilirubin levels no more than that in Stage IIA circulatory insufficiency.

[Prognosis of the clinical course of post-infarction cardiosclerosis on the basis of pyrophosphate-labeled myocardial scintigraphy]. / Prognozirovanie klinicheskogo techeniia postinfarktnogo kardioskleroza po dannym stsintigrafii miokarda s mechenym pirofosfatom.

Predictive value of myocardial 99mTc-pyrophosphate scintigraphy was assessed in 122 patients with postinfarction cardiosclerosis. In those cases where clinical and scintigraphic complication risk estimates considered, further evidence was shown to be redundant. Prognosis in patients with positive scintigraphic results and asymptomatic postinfarction cardiosclerosis or first-to-second class stable angina should take into account the size of myocardial pyrophosphate accumulation focus and the pattern of stress-induced changes in blood supply of the sites of myocardial damage. Negative scintigraphic results have no predictive value in those postinfarction cardiosclerosis patients who show clinical signs of heart failure and/or severe coronary insufficiency at the time of investigation.

[Means of differential diagnosis between angina pectoris and neurocirculatory dystonia]. / Sposob differentsial'noi diagnostiki stenokardii i neirotsirkuliatornoi distonii.

Plasma somatotropic hormone and cortisol were measured at rest, at the peak of physical stress and 2 hours after the discontinuation of exercise in 15 normal male subjects, 18 male patients with neurocirculatory dystonia and 69 with angina pectoris. The determination of one-dimensional hyperplanes of plasma STH and cortisol during and after exercise allows one to distinguish anginal patients from those with neurocirculatory dystonia and make a diagnosis in patients with nonspecified chest pains.

[Clinico-biochemical principles of healing of myocardial infarct]. / Kliniko-biokhimicheskie zakonomernosti reparatsii infarkta miokarda.

Individual glyco- and mucoproteins and collagen metabolites were determined in dynamics in 297 patients with transmural, macrofocal nontransmural, and microfocal myocardial infarction. It is shown that these laboratory findings enable one to appraise the course of myocardial infarction healing. This may serve as one of the criteria for the elaboration of individualized rehabilitation programs.

[A non-invasive method of determining the severity of coronary insufficiency in various forms of ischemic heart disease]. / Neinvazivnyi sposob opredeleniia tiazhesti koronarnoi nedostatochnosti pri nekotorykh formakin ischemicheskoi bolezni serdtsa.

Myocardial pyrophosphate accumulation was examined in various forms of coronary heart disease. The status of the coronary reserve in the myocardial lesion foci where pyrophosphate is accumulated has been shown to determine the severity of coronary failure in various uncomplicated forms of the disease, such as angina without prior myocardial infarction, myocardial infarction in the early phase of its healing, and postinfarction cardiosclerosis. In postinfarction cardiosclerosis, the dimensions of such foci are significant in the development of clinical events of coronary failure.

[Determination of the size of the myocardial lesion by electrocardiographic and pathologico-anatomic methods]. / Opredelenie velichiny porazheniia serdechnoi myshtsy élektrokardiograficheskim i patologoanatomicheskim metodami.

Precordial mapping was performed in 16 patients with acute anteroseptal myocardial infarction admitted to the clinic within 10 hours after the onset of the disease. Changes in the QRS complex, ST segment, and Q and R waves as well as the total number of points with QS type complexes were appraised on the cartograms. The findings of precordial mapping were compared with the mass and area of the affected tissue determined on autopsy. It was established that the number of QS type complexes recorded on the cartogram is highly informative in appraising the mass of myocardial infarction. The extreme values of the area of the QS complex and R wave correlate well with the area of the affection. The revealed regularities made it possible to deduce a formula for determining the mass of damaged tissue in various degrees of necrosis.