When mechanisms of coalescence and sintering at the nanoscale fundamentally differ: Molecular dynamics study.

Employing classical isothermal molecular dynamics, we simulated coalescence of mesoscopic Au nanodroplets, containing from several thousands to several hundred thousands of atoms, and sintering of mesoscopic solid Au nanoparticles. For our atomistic simulations, we used the embedded atom method. The employed open access program large-scale atomic/molecular massively parallel simulator makes it possible to realize parallel graphical processing unit calculations. We have made a conclusion that the regularities and mechanisms of the nanodroplet coalescence (temperature is higher than the nanoparticle melting temperature) and of the solid nanoparticle sintering differ from each other. We have also concluded that the nanodroplet coalescence may be interpreted as a hydrodynamic phenomenon at the nanoscale whereas sintering of solid nanoparticles is a much more complex phenomenon related to different mechanisms, including collective rearrangements of atoms, the surface diffusion, and other types of diffusion. At the same time, collective rearrangements of atoms relate not only to the solid nanoparticle sintering but also to the nanodroplet coalescence. In general, our molecular dynamics results on sintering of Au nanoparticles consisting of 10 000-30 000 atoms agree with the Ferrando-Minnai kinetic trapping concept that was earlier confirmed in molecular dynamics experiments on Au nanoclusters consisting of about 100 atoms.

Airborne concentrations and chemical considerations of radioactive ruthenium from an undeclared major nuclear release in 2017.

In October 2017, most European countries reported unique atmospheric detections of aerosol-bound radioruthenium (106Ru). The range of concentrations varied from some tenths of µBq·m-3 to more than 150 mBq·m-3 The widespread detection at such considerable (yet innocuous) levels suggested a considerable release. To compare activity reports of airborne 106Ru with different sampling periods, concentrations were reconstructed based on the most probable plume presence duration at each location. Based on airborne concentration spreading and chemical considerations, it is possible to assume that the release occurred in the Southern Urals region (Russian Federation). The 106Ru age was estimated to be about 2 years. It exhibited highly soluble and less soluble fractions in aqueous media, high radiopurity (lack of concomitant radionuclides), and volatility between 700 and 1,000 °C, thus suggesting a release at an advanced stage in the reprocessing of nuclear fuel. The amount and isotopic characteristics of the radioruthenium release may indicate a context with the production of a large 144Ce source for a neutrino experiment.

[Laparoscopy in emergency surgery of rare atypical diseases]. / Videolaparoskopiya v ekstrennoi khirurgii redko vstrechayushchikhsya, atipichnykh zabolevanii.

OBJECTIVE: To analyze the capabilities of laparoscopy in the diagnosis and treatment of atypical diseases. MATERIAL AND METHODS: Laparoscopy was performed in 5188 patients with established, suspected and unclear diagnosis of acute surgical diseases for the period from 2008 to 2018. Rare atypical diseases were diagnosed in 114 (2.2%) patients. These diseases simulated established and suspected clinical diagnoses in 100 (87.7%) cases, and the diagnosis was unclear in 5 (4.4%) cases. In 9 (7.9%) patients, atypical diseases were concomitant. In 7 cases, atypical diseases competed with the underlying disease and required emergency surgery. Conservative treatment was required in 2 cases. Seventy (61.4%) patients with atypical diseases needed emergency surgery, and 44 (38.6%) patients required conservative treatment. Laparoscopic operations were performed in 61 (87.1%) patients including simultaneous procedures in 8 cases and video-assisted interventions in 2 (2.9%) patients. Laparotomy was applied in 7 (10.0%) patients. RESULTS: Histological examination confirmed laparoscopic diagnosis in 66 out of 68 specimens. Cells of mucus-forming adenocarcinoma were detected in one resected epiploic appendix, carcinomatosis - in one segment of resected omentum. CONCLUSION: Video-assisted laparoscopy was valuable to establish a diagnosis and determine surgical strategy, detect competing and concomitant diseases, perform operations including simultaneous procedures.

[Laparoscopy in emergency abdominal surgery]. / Videolaparoskopiya v ekstrennoi khirurgii organov bryushnoi polosti.

OBJECTIVE: To evaluate the possibilities of laparoscopy in the diagnosis and treatment of acute abdominal surgical diseases. MATERIAL AND METHODS: A retrospective analysis of laparoscopic procedures in 4655 patients with confirmed or suspected acute abdominal surgical diseases for the period 2008-2017 was performed. Laparoscopy was applied to confirm or to determine unclear diagnosis. RESULTS: Diagnosis was established and confirmed in 4526 (97.2%) patients. Advisability of laparoscopic surgery was confirmed in 3091 (68.3%) patients, laparotomy - in 491 (10.8%) patients. Surgical treatment was not required in 944 (20.9%) patients. Laparoscopic procedures were performed in 3050 (98.7%) patients, 41 (1.3%) patients required conversion to laparotomy. Laparoscopic approach failed to define diagnosis in 129 (2.8%) patients that required conversion to diagnostic laparotomy. CONCLUSION: Laparoscopic was valuable to establish the diagnosis and determine surgical strategy, diagnose concomitant diseases, perform operations including simultaneous ones.

[Laparoscopy for perforated gastroduodenal ulcers]. / Videolaparoskopiia pri perforativnykh gastroduodenal'nykh iazvakh.

AIM: To assess laparoscopy in diagnosis and treatment of patients with perforated gastroduodenal ulcers. MATERIAL AND METHODS: There were 273 patients with perforated gastroduodenal ulcers who underwent laparoscopy at the Sklifosovsky Research Institute for Emergency Care in 2010-2016. Sample included patients with clinical and instrumental diagnosis of perforated gastroduodenal ulcers, suspected hollow organ perforation including perforated ulcer and other acute abdominal diseases followed by perforated ulcer. RESULTS: Laparoscopy confirmed diagnosis of perforated gastroduodenal ulcer in 82.5% of patients with clear preoperative diagnosis and in 54.2% of patients with suspected perforated ulcer. Video-assisted closure of the ulcer is possible in 81.7% of patients. Any endoscopic procedure should be started from diagnostic measures. Diagnostic laparoscopy followed by curative laparotomy in 14.6% of patients was able to clarify diagnosis, suture technically difficult perforated ulcer and prevent possible complications.

[Videolaparoscopy in diagnosis and treatment of diseases simulating acute appendicitis]. / Vozmozhnosti videolaparoskopii v diagnostike i lechenii zabolevanii, simuliruiushchikh ostryi appenditsit.

AIM: To analyze videolaparoscopic diagnosis and treatment of abdominal pathology simulating acute appendicitis (AA). MATERIAL AND METHODS: For the period 2008-2015 at Sklifosovsky Research Institute of Emergency Care 2784 patients with suspected AA underwent clinical, laboratory and ultrasonic examination. Depending on survey results patients were divided into 2 groups. Group I included 1352 (48.6%) patients with AA, group II - 1432 (51.4%) patients with suspected AA. All of them underwent videolaparoscopy. RESULTS AND DISCUSSION: Videolaparoscopy confirmed AA in 1308 (96.7%) patients of group I and 856 (59,8%) patients of group II. In the 1st group 36 (2.7%) patients had pathology simulating AA and 8 (0.6%) patients had not organic changes; in the 2nd group these values were 462 (32.3%) and 114 (7.9%) respectively. Absence of organic changes was explained by functional bowel disorders. In 95 (3.4%) out of 498 (17.9%) patients of both groups with simulating diseases videolaparoscopy was made and in 49 (1.8%) cases indications for laparotomy were established. In 354 (12.7%) patients with simulating diseases and 122 (4.4%) patients without organic changes operations were not carried out. CONCLUSION: Videolaparoscopy in patients scheduled for appendectomy or with unclear clinical picture allows to diagnose various forms of AA, simulating diseases and to perform necessary surgery.

[OPTIMIZATION OF REPARATIVE OSTEOGENESIS JAWS ON AGING (PRECLINICAL STUDIES)].

The article presents the results of pre-clinical studies of the possibility of optimization of reparative osteogenesis in postoperative bone cavities of the jaws in old rats with a peptide bioregulator of Kartalaks. Using histological and morphometric methods in the experimental study, it is shown that the use of Kartalaks positive effect on the course of the process of reparative osteogenesis of the mandible in old rats. The features of the Kartalaks drug investigated for optimization of reparative osteogenesis jaw during aging. It is found that by using Kartalaks in old animals to 30 days before the surgical intervention, the process of reparative osteogenesis standard defect of mandible occurs at early stages (before 30 days), similar to the control. The deadlines for 60-120 days from the beginning of the experiment using the peptide bioregulator Kartalaks, noted the formation of a complex regenerate tissue containing a smaller proportion of connective tissue and cartilage, as well as more advanced remodeling of newly formed bone tissue compared with the control group, and older animals who received the drug after performing surgery.

[Videolaparoscopic and morphological parallels in diagnosis of different forms of acute appendicitis].

AIM: To compare results of macroscopic assessment and materials of histological examination of 1635 appendices removed using videolaparoscopy in patients with acute appendicitis. All patients have been treated in N.V.Sklifosovsky Research Institute of Emergency Care for the period from 2002 to 2014. MATERIAL AND METHODS: Intraoperative macroscopic assessment of appendix's inflammatory changes was performed using some conventional signs. Сatarrhal, phlegmonous and gangrenous changes were suspected in 77 (4.7%), 1432 (87.5%) and 126 (7.7%) cases respectively. RESULTS: Histological examination revealed catarrhal, phlegmonous and gangrenous changes in 86 (5.3%), 1338 (81.8%) and 115 (7.0%) cases respectively. In 65 (4.0%) patients changes were estimated as chronic, 31 (1.9%) patients had not inflammation. Intraoperatively suspected diagnosis of different forms of appendicitis was confirmed by histological survey in 94.1%. Most cases of matched intraoperative and histological diagnosis were observed in case of phlegmonous appendicitis (88.2%). Only 5.9% of patients had not acute inflammation of appendix that may be explained by overdiagnosis and excess of indications for appendectomy.

[THE BIOCHEMICAL AND PATHOPHYSIOLOGICAL MARKERS OF CHEMICAL EFFECT ON ORGANISM, THEIR INFORMATIVENESS AND DIAGNOSTIC SIGNIFICANCE].

The sampling of study included 185 examined workers. Out of them 90 work at "Opitnii zavod Neftekhim" (67 females and 23 males) and 95--at "Kaustik" (64 females and 31 males) from various workshops of the given enterprises. To determine biochemical indicators samples of blood, saliva and urine were collected. The study was carried out in concordance with ethic principles of the Helsinki world medical association declaration, 2008 ed. with receiving written consent of patient to participate in study.

[Photogenerator of trichloroacetic acid--a perspective detritylation agent for microchip oligonucleotide synthesis].

For the purpose of new detritylation agents search for microarray oligonucleotide synthesis we investigated applicability of [4-(4-methoxyphenyl)-2,6-dinitro-phenyl](phenyl)methyl 2,2,2-trichloroacetate for 4,4'-dimethoxytrityl group detritylation during oligonucleotide syntheses generating trichloroacetic acid at radiation by light with a length of wave of 405 nanometers. [4-(4-Methoxyphenyl)-2,6-dinitro-phenyl](phenyl)methyl 2,2,2-trichloroacetate has been successfully used for solid-phase oligonucleotide synthesis of desired oligonucleotides.

[Mini-invasive technologies in treatment of acute cholecystitis in patients with high operational and anesthetic risk].

The treatment results of 769 patients with acute calculous cholecystitis and high operational and anesthetic risk at admission are presented in the retrospective study. High risk was determined by expressed comorbidities, diseases' terms, the complications of acute cholecystitis, age, which was more than 60 years in most cases. The patients were divided into 2 groups depending on the severity of comorbidity and the possible effects of its correction. The first group included 617 perspective patients for cholecystectomy. And the second group included 152 patients unpromising for this. Concept of stage treatment was used in the first group including primary decompression of the gallbladder by using of percutaneous transhepatic micro-cholecystostomy under ultrasound guidance. Cholecystectomy was performed after correction of comorbidities, complications of acute cholecystitis, and readjustment of extrahepatic bile ducts by endoscopy if necessary. Laparoscopic cholecystectomy was successfully performed in 587 patients. There was open cholecystectomy in 11 cases. Cholecystectomy was done in 19 patients as a result of conversion. Cholecystostomy from minimal access with extraction of stones under local anesthesia was performed in the second group for decompression and as definitive treatment. There was not observed deaths in patients with high operational and anesthetic risk as a result of such tactics. Postoperatively 1.7% of patients had complications that were successfully resolved.

[Contemporary state of work conditions and occupational morbidity of workers engaged into rubber, mechanical rubber and tire industries].

Based on analysis of materials provided by occupational safety department PC "UZEMiK" and JSC "Kauchuk", the authors evaluate contemporary work conditions and occupational morbidity in workers engaged into rubber, mechanical rubber and tyre industries.

[Medico-social and psychosomatic status of gerontostomatologic patients].

Assessment of medico-social and psychosomatic status of patients of the advanced and senile age having dental diseases was carried out. The results of the study show that the level of stomatological morbidity in this contingent of patients is rather high, and the treatment must be carried out with obligatory participation of doctors-interns and taking into account mental health of a person.

[Gerontostomatology's topical issues in Russia at the present stage].

Gerontostomatology is one of the most important interdisciplinary sections of the medicine, studying mechanisms of aging of the chewing device of a person, and also carrying-out search of decisions in treatment of stomatologic diseases in persons of the senior age groups, at the same time increasing quality of their life. The article covers actual problems of modern gerontostomatology in Russia.

[Application of bioregulating therapy in complex treatment of temporomandibular joint diseases in people of elderly and senile age].

The results of dynamic supervision over application a peptide bioregulator of "Sigumir" in complex treatment of 62 patients of the senior age groups with various diseases of a temporomandibular joint are presented. It is shown that application of a complex of treatment-and-prophylactic actions, including rational tooth prosthetics, functional and pharmacotherapy (including accompanying diseases), and also use a peptide bioregulator of cartilaginous and bone tissues "Sigumir" in complex therapy of patients with diseases of a temporomandibular joint of a various etiology, enables to stop in short-terms a painful syndrome in such patients, to increase amplitude of opening of a mouth, to improve chewing function, to reduce terms of treatment and to provide preventive maintenance of relapses of TMJ's pathology during all period of supervision.

[Detection of temporomandibular joint diseases in elderly and senile age in ambulatory medicoprophylactic institutions].

The research analyzes diagnostic TMJ's disease's identification work of stomalogists owned to different types of day care properties (municipal, departmental, private). This research based on examination of primary medical records of 1906 patients aged 61 to 89 years, including 2978 prescribing lists made by stomatologists - orthopedists to dental outpatient's card. This research shows that in case of outpatient conditions in the primary examination of patients of elderly and senile age stomatologists pay attention to joint pathology in the presence of acute patients' complaints, caused by TMJ's displacement, arthritis, painful TMJ's dysfunction or pronounced sound phenomena of TMJ. Stomatologists examine TMJ's pathology more particularly. The TMJ's pathology complicates the tooth replacement made to patients contrary to absence of indications of disease presence in primary medical records. The prepared conclusion and recommendations allow improving the outpatient diagnosis of TMJ's pathology.

[The energy status of erythrocytes upon exposure to chemical pollutants].

The paper gives the results of a study of energy metabolism in the red blood cells of the workers from OAO "Salavatnefteorgsinthez" of petrochemical industry. The energy metabolism has been found to substantially change in the examinees in contact with a mixture of organic solvents and a mixture of chlorinated solvents under industrial conditions.

[Metabolic processes in the body exposed to chemical pollutants].

The paper gives the results of studying the processes of free radical and microsomal oxidation, antioxidant defense, and energy and electrolyte metabolism in the workers of OAO "Salavatnefteorgsintez", one of the leading petrochemical plants in the Republic of Bashkortostan. The metabolic processes have been found to substantially change in the persons contacting a mixture of chlorinated and aromatic hydrocarbons under industrial conditions.

[The morbidity with temporary disability among workers of petrochemical industry].

The article deals with the data on morbidity with temporary disability among workers producing rubber and mechanical rubber articles in petrochemical industry. The leading place in the structure of morbidity is taken by the diseases of nervous and cardiovascular systems, liver, gastrointestinal tract, respiratory system and thyroid gland.

[Free radical oxidation-antioxidant defense system upon exposure to industrial chemical pollutants].

The paper gives the results of studying the free radical oxidation-antioxidant defense (FRO-AOD) system in the blood, saliva, and urine of workers from the petrochemical industry OAO "Salavatnefteorgsintez". The FRO-AOD system has been ascertained to be considerably changed in the plasma, tear, and urine of persons contacting a mixture of petrol and Grade BP-1 solvent with organic solvents and aromatic hydrocarbons and a mixture of 1,2-dichloroethane with chlorinated hydrocarbons under industrial conditions.