Simultaneous Replacement Research Articles

The roles of diffusion and convection in ventilation of animal burrows.

The relationship between body mass and the respiratory microenvironment of burrowing animals is examined using artificial burrows containing surrogate animals that simulate O2 consumption by removal of air and simultaneous replacement with N2. Allometric relationships between body mass and burrow radius, nest chamber radius, and O2 consumption rate show that published mathematical predictions of diffusion-mediated gas exchange are adequate to describe the respiratory environments of animals in small blind-ending burrows through porous substrata. Diffusion is sufficient to ventilate burrows containing small mammals weighing less than 340g, or subterranean nest chambers connected to the surface by one or more tunnels containing mammals weighing less than 30kg. Outside of these limits, convection prevails and prevents the development of hypoxic conditions, particularly in burrows of mammals weighing more than 1300g.

Two Cases of Simultaneous Abdominal Aortic Replacement and Thoracic Endovascular Aortic Repair after Arch Replacement for Abdominal Aortic Aneurysm with Type A Acute Aortic Dissection

急性A型大動脈解離を発症した腹部大動脈瘤2例に対して急性期に弓部置換術を行い，二期的に腹部大動脈人工血管置換術および残存したentry閉鎖と大動脈のリモデリングを期待して胸部ステントグラフト内挿術を施行した。2例とも術後対麻痺の合併症は認めず，術後CTで良好なリモデリングが得られた。今回施行した術式は安全かつ有用な治療の選択肢の1つとなりうると考えられた。

Evaluating the synergic effect of waste rubber powder and recycled concrete aggregate on mechanical properties and durability of concrete

The use of waste materials in the concrete mixture can help human beings to preserve the environment and achieve environmentally-friendly concrete. In this study, the influences of simultaneous replacements of cement by waste rubber powder (WRP) and coarse aggregate by recycled concrete aggregate (RCA) on the mechanical properties and durability of concrete were investigated experimentally. To do so, concrete specimens containing the WRP with the replacement ratios of 0 %, 2.5 %, and 5 % by weight of cement, and the RCA with the replacement levels of 0 %, 25 %, and 50 % of coarse aggregate were prepared. Moreover, different water to binder ratios and binder content were used. Mechanical properties of the concrete specimens consisting of compressive, flexural, and tensile strengths and the durability test of rapid chloride migration test (RCMT) were carried out at different ages. It was observed that the mechanical properties of concrete decrease by raising the proportions of recycled materials in all replacement ratios. Because of the negative effects of the WRP and RCA on, respectively, the cement matrix and the interfacial transition zone, the reduction of the mechanical properties are higher for the concrete specimens with both recycled materials. In the case of durability, the migration rate of chloride ions in concrete reduces by increasing the WRP rates due to the blockage of micro-pores connections. However, adding the RCA has a negative effect on the durability performance of concrete. Finally, four equations were proposed and evaluated for the compressive, tensile, flexural strength reduction and durability factors of concrete containing the WRP and RCA using the genetic programming.

Valve-sparing aortic root replacement in adult patients with congenital heart disease.

Aortic root dilatation is frequently observed in patients with congenital heart defects (CHD), but has received little attention in terms of developing a best practice approach for treatment. In this study, we analysed our experience with aortic valve-sparing root replacement in patients following previous operations to repair CHD. In this study, we included 7 patients with a history of previous surgery for CHD who underwent aortic valve-sparing operations. The underlying initial defects were tetralogy of Fallot (n = 3), transposition of great arteries (n = 2), coarctation of the aorta (n = 1), and pulmonary atresia with ventricle septum defect (n = 1). The patients' age ranged from 20 to 40 years (mean age 31 ± 6 years). David reimplantation was performed in 6 patients and a Yacoub remodelling procedure was performed in 1 patient. Four patients underwent simultaneous pulmonary valve replacement. The mean interval between the corrective procedure for CHD and the aortic valve-sparing surgery was 26 ± 3 years. There was no operative or late mortality. The patient with transposition of great arteries following an arterial switch operation was re-operated 25 months after the valve-sparing procedure due to severe aortic regurgitation. In all other patients, the aortic valve regurgitation was mild or negligible at the latest follow-up (mean 8.7 years, range 2.1-15.1 years). Valve-sparing aortic root replacement resulted in good aortic valve function during the first decade of observation in 6 of 7 patients. This approach can offer a viable alternative to root replacement with mechanical or biological prostheses in selected patients following CHD repair.

Intraday analysis of regulation change in microstructure: evidence from an emerging market

PurposeThis study investigates the impact of simultaneously replacing both midday single-price call auction and lunch break with multi-price continuous trading on intraday volatility–volume patterns as well as the intraday volatility–volume nexus.Design/methodology/approachThe analysis utilises 150 m tick-by-tick transaction data related to 333 stocks traded on Borsa Istanbul Equity Market covering a period of 2 months prior to and following the change. In addition to graphic comparisons, the study uses difference in mean tests, panel-fixed generalized least squares (GLS), panel-random GLS and random-effects linear models with AR(1) disturbance regression estimations.FindingsThe results show that intraday volatility and trading volume form an inverse J-shape and are positively correlated. It is observed that the implementation of the regulation change decreased intraday volatility and increased trading volume. Additionally, the results indicate a negative volatility–liquidity and a positive volume–liquidity relationship, supporting the mixture of distribution hypothesis.Research limitations/implicationsEnhanced market efficiency provides greater opportunity for investment and risk management. Investors can benefit from the findings on the intraday volatility–volume nexus, which is an indicator of informed trading, and regulatory authorities can use volume to oversight volatility.Originality/valueThis very rare regulation change of the simultaneous replacement of the lunch break and midday call auction with continuous trading is investigated in the context of intraday volume and volatility. This study also expands upon some important findings on the volume–volatility nexus for the Turkish Stock Market.

Combined Replacement of Aortic Valve and Ascending Aorta-A 70-Year Evolution of Surgical Techniques.

Simultaneous replacement of the ascending aorta and aortic valve has always been a challenging procedure. Introduction of composite conduits, through various ingenious procedures and their modifications, has changed the outlook of patients with aortic valve disease and ascending aorta pathology. In the past 70 years, progress of surgical techniques and prosthetic materials has allowed such patients to undergo radical procedures providing excellent early and long-term results in both young and elderly patients. This article aims to review the most important technical advances in the treatment of aortic valve disease and ascending aorta aneurysms recognizing the important contributions in this field.

A short term analysis of the clinical and functional outcome following total knee arthroplasty for osteoarthritis

Aim: The aim of this short term prospective study is to present a data on the clinical and functional outcome of total knee arthroplasty done for primary osteoarthritis.Method and Material: It is a Prospective study was conducted at Bapuji and Chigateri General Hospital attached to JJM Medical College, Davangere for a period of two years from July2018 to July 2020. Patients with primary Osteoarthritis of the knee joint, undergoing TKA were included in the study. Patients with less than 6 months follow up and patients lost to follow up were excluded from the study.Result: A total of 30 knee replacements performed in 22 pateints were included. The average age is 62.4 yrs at the time of surgery. There were 17 females and 5 males in our study. 12 Pateints had unilateral total knee replacements. 6 pateints underwent simultaneous bilateral total knee replacements in a single stage. 3 pateints had staged bilateral total knee replacements. 22 Knees (73.33%) were completely pain free at final follow up, 6 knees (20%) had mild (or) occasional vague pain, 2 knee (6.66%) had pain for climbing stairs only. Average Pre op ROM was 86.4 degrees which improved to 99.6 degrees. All the 30 knees were stable anteroposteriorly both pre & post operatively. 4 knees were unstable mediolaterally which was corrected post operatively. 28 knees had varus deformity of avg 11.08 degree and 2 knee had valgus deformity of 20 degrees. All the knees were correctable to an average postoperative valgus of 4.4 degrees. Knee society clinical scoring system the average score for all the 30 knees was 35 points preoperatively and average score was 93 points at final follow up with 26 knees (86.66 %) had excellent final scores. The average preoperative functional score was 36 which improved to an average functional score of 90 postoperatively at final follow up with 25 knees (83.33 %) had excellent functional scores. No evidence of malalignment (or) loosening in the femoral and tibial components was noted.Conclusion: This is a study with a short term follow up ranging from 6 months to 26 months. Functional results have been good irrespective of the severity of the preoperative deformities. Patient satisfaction in terms of pain relief, and improvement in walking and stair climbing ability is good following total knee arthroplasty for osteoarthritis.

Огляд нової нормативної бази 2019–2020 років щодо декарбонізації економіки та аналіз її впливу на умови функціонування газової галузі України

The purpose of this paper is to explore the influence of the new Ukrainian and European regulatory framework for 2019-2020 concerning the decarburization of economy of the functioning of Ukrainian gas industry. The paper provides an overview of the Ukrainian regulatory framework of 2019–2020 on the implementation of the system of monitoring, reporting, and verification of greenhouse gas emissions in our country. We also provide an overview of new European documents on the decarbonisation of economy, in particular, the European Green Deal, the EU Strategy for Reducing Methane Emissions, and the Hydrogen Strategy for Climate-Neutral Europe. We showed that these EU documents will exert a significant influence on the functioning of both the energy sector of our country as a whole and its part – gas industry. The paper shows that, under the existing plans of the development of energy sector in European countries in order to reach the state where there are no net emissions of greenhouse gases by 2050 and under conditions of fierce competition for sources and routes of gas supply to the European market, the most pressing problem confronting the gas transportation system of Ukraine is to optimize its structure with simultaneous replacement of outdated compressor equipment by modern one with lower carbon dioxide emissions, which will require a significant amount of investment. Under such conditions, it is necessary to study carefully the feasibility of introducing activities for the main transportation of gas under the action of Greenhouse Gas Trading System. We also showed that the reduction of methane emissions along the natural gas chain supply in accordance with the EU Strategy for the reduction of methane emissions is extremely important for Ukraine. In addition to the implementation of measures for reducing these emissions, it is necessary to attract attention to the development of national methods for estimating methane emissions and the use of national coefficients in the formation of the National Greenhouse gas emissions inventory for estimating volatile emissions from natural gas activities. Keywords: monitoring, reporting and verification of greenhouse gas emissions, Greenhouse Gas Trading System, decarbonisation, European Green Deal, gas transportation system

Controlling the coordination environment of Co atoms derived from Co/ZIF-8 for boosting photocatalytic H2 evolution of CdS

Regulating the coordination environment of metal–Nx species by replacing N with low electronegativity atoms is an approach of tuning the electrocatalytic performance of metal-based sites. However, such effects on the enhancement of photocatalytic H2 evolution over semiconductors are not discussed yet. Herein, we designed and prepared Co-based cocatalysts with controlled coordination environment via calcination Co/ZIF-8 loaded with triphenylphosphine followed by a sulfurization treatment. It was then used as cocatalyst to modify CdS. The effects of the coordination environment of Co atoms on the H2 evolution activity of CdS were discussed. The obtained Co was co-stabilized by N, P, and S atoms and embedded in graphitic carbon (denoted as Co-NxPS/C). Experimental results indicated that the Co-NxPS/C exhibited high activity in enhancing H2 evolution of CdS with a value of 1260 μmol after 5 h irradiation. The simultaneous replacement of N with P and S atoms in N-stabilized Co embedded in carbon could enhance light harvesting, accelerate the transfer of photogenerated electrons from CdS to carbon with increased electrons accumulation ability and conductivity, improve charge separation efficiency, and enhance proton reduction kinetics. It is believed that the results of this study could promote the development of other high performance MOF-derived atomically dispersed cocatalysts to increase photocatalytic H2 evolution.

Molecular Origin of Carbon–Oxygen‐Bridge Isomerization Induced Reverse Aggregation Ability in Acceptor–Donor–Acceptor Electron Acceptors for Organic Solar Cells

For bulk heterojunction organic solar cells (OSCs), controlling molecular self‐aggregation during solution processing is crucial to obtain ideally phase‐separated morphology and high device performance. Recently, fused‐ring regiochemistry, for example, carbon–oxygen (CO)‐bridge isomerization, has been found to effectively modulate the aggregation structures and photovoltaic properties of acceptor–donor–acceptor (A–D–A) small‐molecule acceptors (SMAs). Strikingly, the relative aggregation ability for the CO‐bridge isomers turns out to be reverse after simultaneous replacement of the linear alkyl side chains with branched ones and fluorination of the end groups. Herein, to understand the molecular origin of such an observation, the aggregation behaviors of three pairs of CO‐bridge isomeric SMAs in solutions are systematically investigated by atomistic molecular dynamics simulations. Because of the large side‐chain steric hindrance around the fused‐ring core, the molecular self‐aggregation for all of these SMAs is dominated by end‐group π–π stacking. Moreover, the end‐group π–π interaction is controlled by the synergistic effect of CO‐bridge isomerization, side‐chain branching, and end‐group fluorination, which are responsible for the reversal of the aggregation ability of the isomeric SMAs. This work provides the rationalization of experimental observations and is helpful for modulating the blending morphologies for high‐efficiency OSCs based on CO‐bridge SMAs.

Suppression-Replacement KCNQ1 Gene Therapy for Type 1 Long QT Syndrome.

Type 1 long QT syndrome (LQT1) is caused by loss-of-function variants in the KCNQ1-encoded Kv7.1 potassium channel α-subunit that is essential for cardiac repolarization, providing the slow delayed rectifier current. No current therapies target the molecular cause of LQT1. A dual-component suppression-and-replacement (SupRep) KCNQ1 gene therapy was created by cloning a KCNQ1 short hairpin RNA and a short hairpin RNA-immune KCNQ1 cDNA modified with synonymous variants in the short hairpin RNA target site, into a single construct. The ability of KCNQ1-SupRep gene therapy to suppress and replace LQT1-causative variants in KCNQ1 was evaluated by means of heterologous expression in TSA201 cells. For a human in vitro cardiac model, induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) were generated from 4 patients with LQT1 (KCNQ1-Y171X, -V254M, -I567S, and -A344A/spl) and an unrelated healthy control. CRISPR-Cas9 corrected isogenic control iPSC-CMs were made for 2 LQT1 lines (correction of KCNQ1-V254M and KCNQ1-A344A/spl). FluoVolt voltage dye was used to measure the cardiac action potential duration (APD) in iPSC-CMs treated with KCNQ1-SupRep. In TSA201 cells, KCNQ1-SupRep achieved mutation-independent suppression of wild-type KCNQ1 and 3 LQT1-causative variants (KCNQ1-Y171X, -V254M, and -I567S) with simultaneous replacement of short hairpin RNA-immune KCNQ1 as measured by allele-specific quantitative reverse transcription polymerase chain reaction and Western blot. Using FluoVolt voltage dye to measure the cardiac APD in the 4 LQT1 patient-derived iPSC-CMs, treatment with KCNQ1-SupRep resulted in shortening of the pathologically prolonged APD at both 90% and 50% repolarization, resulting in APD values similar to those of the 2 isogenic controls. This study provides the first proof-of-principle gene therapy for complete correction of long QT syndrome. As a dual-component gene therapy vector, KCNQ1-SupRep successfully suppressed and replaced KCNQ1 to normal wild-type levels. In TSA201 cells, cotransfection of LQT1-causative variants and KCNQ1-SupRep caused mutation-independent suppression and replacement of KCNQ1. In LQT1 iPSC-CMs, KCNQ1-SupRep gene therapy shortened the APD, thereby eliminating the pathognomonic feature of LQT1.

High-intensity flight feather molt and comparative molt ecology of warblers of eastern North America

Abstract Rapid high-intensity molt of flight feathers occurs in many bird species and can have several detrimental consequences, including reductions in flight capabilities, foraging performance, parental care, and plumage quality. Many migratory New World warblers (family Parulidae) are known to have intense remigial molt, and recent work has suggested that simultaneous replacement of the rectrices may be widespread in the family as well. However, the phylogenetic distribution of simultaneous rectrix molt, and high-intensity flight feather molt more generally, has not been systematically investigated in warblers. We addressed this issue by examining flight feather molt in 13 species, representing 7 different warbler genera, at Powdermill Avian Research Center in southwestern Pennsylvania, USA. All 13 species replaced their 12 rectrices simultaneously, with the onset of rectrix molt occurring in the early-middle stages of high-intensity primary molt. As expected, single-brooded early migrants molted earlier than double-brooded species whose nesting activities extend into late summer. However, our finding that late-molting species replaced their primaries more slowly and less intensively than early molting species was unexpected, as late-molting species are widely hypothesized to be under stronger migration-related time constraints. This surprising result appears to be at least partially explained by a positive association between the pace of molt and daylength; shorter late-summer days may mandate reduced daily food intake, lower molt intensity, and a slower pace of molt. In comparison to other passerines, flight feather molt in warblers of eastern North America is extraordinarily intense; at its peak, individuals are simultaneously replacing 50–67% of their 48 flight feathers (all 12 rectrices and 6–10 remiges on each wing) for 2–3 weeks or more. Because molt of this intensity is likely to present numerous challenges for flight, avoiding predators, foraging, and parental care, the period of flight feather molt for warblers constitutes a highly demanding phase of their annual cycle.

RENT AS A FINANCIAL INSTRUMENT FOR REGULATING THE DEVELOPMENT OF THE AGRARIAN SECTOR OF ECONOMY


 The development of the agrarian sector of the economy, as well as of the entire national economy, should be based on a clear and consistent state regulatory policy. Rent is one of the most effective financial instruments for regulating the development of the agrarian sector.
 As a whole, rent is defined as the income of any resources (production factors) owner that is not related to business activity. Onwards, economic rent is an over-income that the owner receives from using a variety of quality resources, the supply of which is limited in the long run. From the financial point of view, rent is part of the entrepreneur’s income, his unearned income. The consequence of excessive and uncontrolled macro-level rent-seeking behavior is the so-called «Dutch disease», which causes concentration of labor and capital in the services sector, its outflow from the real economy and the simultaneous replacement with unproductive inputs.
 It is determined that the rent saturation of the GDP of Ukraine exceeds the world average values, that designates the national economy as a commodity one, testifies to the developmental, transitive nature of the economy, its direct dependence on the developed countries. Moreover, the dynamics of the annual indices of the physical volume of Ukraine’s GDP coincides with the dynamics of its rent withdraw, which shows the direct dependency of goods production and rent, thus defining the economic system as extensive and reindustrialized.
 It is proved that amid non-renewable natural resources depletion, the economy of Ukraine is losing its potential and without drastic transformations, changes in technological structure and development of vertical integration, the crisis will only deepen. The implementation of the proposed measures will contribute to the return of rental over-income to those who have a constitutional right to get it, will provide additional financial resources to fulfill local budgets, especially rural territorial communities.

Strength and microstructural analysis of nano-silica based cement composites in presence of silica fume

Replacement of cement with pozzolanic materials has addressed numerous inquiries identified with impact of these materials on the microstructural and other properties of cement composites. On the other hand, because of the absence of technique and pertinent supporting information, an appraisal of general execution of such admixtures is hard to be completed. The utilization of pozzolanic materials as cement substitution in mortar has enhanced the execution of their physico-chemical and mechanical properties. In this study, the composition of silica fume (SF) was differed as 3%, 6%, 9% and 12% at a fixed composition of nano-silica (NS) as 0.5% by weight for substitution of cement. The fresh and hardened properties of cement mortars were analyzed and microstructural analysis was performed. The specimens were found to exhibit better developed microstructure and enhanced compressive strength with inclusion of optimized dosage of SF in presence of NS. The study has confirmed that the simultaneous replacement of cement with the optimized dosage of pozzolanic materials brings improvement in the properties of the cement mortar and can be used to partially substitute cement for the beneficiary effects.

Диференційований підхід до ортодонтичного лікування дітей із зубощелепними аномаліями, обтяженими дефектами зубних рядів

Summary. Modern protocols on providing orthodontic care of children with anomalies and secondary dento-maxillaire deformities include the use of functional- guiding and mechanically-operated orthodontic equipment based on specific clinical indications. At the same time, the issues of orthodontic treatment of dento-maxillaire anomalies complicated by dentition defects still remain controversial, as the vast majority of functionally-guiding and mechanically-operated orthodontic equipment does not provide simultaneous replacement of dentition defect, whereas methods of pediatric prosthetics are often limited by the use of claspless removable laminar prostheses. Their functional efficiency is low due to insufficient fixation and the need for periodic replacement due to the growth of jaws in accordance with the age and physiological development of a child’s body. The use of traditional fixed bridge prostheses during the period of jaws growth is unacceptable, whereas the manufacture of split bridge prostheses with an intermediate part in the form of sliding elements, movably interconnected, as well as cantilever bridges, is limited by dentition due to the removal of only one tooth. Orthodontic appliances that meet these requirements, should be used to replace dentition defects, combined with dento-maxillaire anomalies in each period of formation of the dento-maxillaire system, which determines the relevance of our research. Goal. To increase the effectiveness of comprehensive treatment of children with dento-maxillaire anomalies, complicated by dentition defects of the frontal area with the use of a prosthetic appliance of our own design. Materials and methods. To achieve this goal, we examined 115 children aged from 5 to 17 years with dentition defects of the frontal area, who applied to the Department of Orthopedic Dentistry and Orthodontics, Kyiv Medical University. Of these, orthodontic treatment was performed in 64 patients with the use of removable and non-removable orthodontic appliances, including a prosthesis appliance of our own design: «Prosthesis appliance for upper jaw expansion » Ukrainian patent for a utility model № 145538 dated 28.12.2020, which is fixed using orthodontic bands and temporary fixation cement on the second temporary molars. The appliance has a plastic base with a screw, with which, if necessary, it is possible to influence the growth of the jaw. It also has artificial teeth in the frontal area, which are connected to the base, and do not inhibit the growth of the frontal segment of the upper jaw. Results. According to the results of the research it is determined that for each period of formation of the dento-maxillaire system with dento-maxillaire anomalies complicated by dentition defects it is reasonable to apply a personalized approach when conducting psycho-emotional preparation for treatment, oral cavity sanation, placing on myogymnastic exercises and appropriate orthodontic treatment combined with pediatric prosthetics. Traditional removable and non-removable orthodontic appliances as well as appliances of our own design were used to treat this group of people. According to the results of the treatment, the use of a fixed orthodontic appliance of our own design in children of young and middle age, which restores the function of biting food, allows to replace the dentition defect and meet the aesthetic requirements of patients, as well as to conduct continuous orthodontic treatment due to impossibility to remove the appliance. Indications for the use of this prosthesis appliance is the absence of 1 to 4 front teeth with the possibility of correcting the transversal size of the jaws. Our proposed prosthesis appliance meets the requirements and is easy for patients to use. Conclusions. Indications for the use of the prosthesis appliance of our own design is the absence of 1 to 4 front teeth with the possibility of correcting of the transversal size of the jaws. The use of a non-removable prosthesis appliance of our own design in children of young and middle age, which restores the function of biting food, allows to replace the dentition defect, meet the aesthetic requirements of patients, and to conduct continuous orthodontic treatment. Key words: dento-maxillaire anomalies, dentition defect, orthodontic treatment, orthodontic appliances, prosthesis appliance.

The influence of zinc and silicate ions on biological properties of hydroxyapatite synthesized by a mechanochemical method

In this study, a mechanochemical method was applied to the synthesis of hydroxyapatite with double and triple substitution. Simultaneous replacement of phosphate ions by carbonate and silicate ions was implemented in the case of double substitution. The triple substitution involved additional replacement of a calcium ion by a zinc ion. The synthesized materials were characterized by X-ray diffraction and Fourier transform infrared spectroscopy. Samples of co-substituted hydroxyapatites in powder form were evaluated in vitro using human osteoblast cell line MG-63 and in vivo via implantation into a bone defect in the rat cranial vault. After 4 days of incubation in vitro, the hydroxyapatite containing zinc, silicon, and carbonate ions with composition Ca9.9Zn0.1(PO4)5.6(SiO4)0.2(CO3)0.2(OH)2 significantly increased cell proliferation in comparison with the other compositions. Four months after the implantation in vivo, this sample showed the greatest ability to integrate into rat skull bones, as evidenced by a morphological analysis of bone sections.

Patient-specific computational fluid dynamics analysis of transcatheter aortic root replacement with chimney coronary grafts.

Transcatheter aortic root repair (TARR) consists of the simultaneous endovascular replacement of the aortic valve, the root and the proximal ascending aorta. The aim of the study is to set-up a computational model of TARR to explore the impact of the endovascular procedure on the coronary circulation supported by chimney grafts. Computed tomography of a patient with dilated ascending aorta was segmented to obtain a 3-dimensional representation of the proximal thoracic aorta, including aortic root and supra-aortic branches. Computed assisted design tools were used to modify the geometry to create the post-procedural TARR configuration featuring the main aortic endograft integrated with 2 chimney grafts for coronary circulation. Computational Fluid Dynamics simulations were run in both pre- and post-procedural configurations using a pulsatile inflow and lumped parameter models at the outflows to simulate peripheral aortic and coronary circulation. Differences in coronary flow and pressure along the cardiac cycle were evaluated. After the virtual implant of the TARR device with coronary grafts, the flow became more organized and less recirculation was seen in the ascending aorta. Coronary perfusion was guaranteed with negligible flow differences between pre- and post-procedural configurations. However, despite being well perfused by chimney grafts, the procedure induces an increase of the pressure drop between the coronary ostia and the ascending aorta of 8 mmHg. The proposed numerical simulations, in the specific case under investigation, suggest that the TARR technique maintains coronary perfusion through the chimney grafts. This study calls for experimental validation and further analyses of the impact of TARR on cardiac afterload, decrease of aortic compliance and local pressure drop induced by the coronary chimney grafts.

Поняття "категорія земель" у концепті сучасного праворозуміння

The article is devoted to the insufficiently studied in the theory of land law the issue of land division into categories, in particular the disclosure of the content of the concept of land category and its qualifications, which underlie such division, and which distinguish categories from each other. There is disagreement with the inconsistent and insufficiently substantiated proposals of some scientists to abandon the categories of land as a post-Soviet remnant of the application of the principle of land use for its intended purpose. It is stated that the refusal to divide land into categories at the current stage of development of land relations will require the simultaneous replacement of all land legislation. It is noted that the concept of "category" in various guises is used in more than four hundred laws of Ukraine. Lexical and legal interpretation of the concept of «category» made it possible to bring its features with their further differentiation into general and special. On the basis of a special feature of land properties (natural and social), a conclusion was made about the inconsistency of the category of lands of industry, transport, communications, energy and defence enshrined in the Land Code of Ukraine with the concept of land category. Keywords: category of lands, division of lands into categories, purpose of lands, signs of the category of lands, land legislation

Modification of ACI209R-92 Concrete Shrinkage Model for Partial Replacement of Cement with Fly Ash and Sand with Pond Ash

Abstract A lot of researchers have been committed to studying various mathematical models for forecasting shrinkage strain developed in concrete and have found many computational models. Those models only predict the linear shrinkage of concrete. But volumetric shrinkage gives clear ideas about shrinkage strain produced inside the structure. However, the previous investigation usually focused on the shrinkage of control cement concrete or cement was replaced with one kind of supplementary cementitious material. The influence of multiple supplementary materials as both cement and sand replacement on shrinkage has not been studied, and this is very important in practice for saving cement and sand. In this research, cement has been replaced with fly ash up to 40 % and sand has been replaced with pond ash up to 20 % individually as well as simultaneously. A total of 27 mixes has been prepared by using three water–cement ratios, and the influence of fly ash and pond ash on volumetric shrinkage has been studied. It is found that when cement is replaced with fly ash up to 40 %, the shrinkage of concrete shows 47 % less than the shrinkage result of control concrete. Similarly, the replacement of sand with pond ash up to 20 % results in the reduction of shrinkage of concrete up to 22 %, and the results for the simultaneous replacement of cement with fly ash and sand with pond ash show a reduction of shrinkage of concrete up to 62 % as compared with the shrinkage of control concrete. Shrinkage strains for all 27 mixes have been determined by using different shrinkage models as well as a laboratory test. It is found that the shrinkage strain found from the ACI model matches with shrinkage strain determined from laboratory tests in a better way as compared with other models. Further, the ACI model has been modified to determine the shrinkage strain of concrete, prepared from supplementary cementitious materials.

Incorporation of Halogenated Amino Acids into Antibody Fragments at Multiple Specific Sites Enhances Antigen Binding.

Expansion of the amino-acid repertoire with synthetic derivatives introduces novel structures and functionalities into proteins. In this study, we improved the antigen binding of antibodies by incorporating halogenated tyrosines at multiple selective sites. Tyrosines in the Fab fragment of an anti-EGF-receptor antibody 059-152 were systematically replaced with 3-bromo- and 3-chlorotyrosines, and simultaneous replacements at four specific sites were found to cause a tenfold increase in the affinity toward the antigen. Structure modeling suggested that this effect was due to enhanced shape complementarity between the antigen and antibody molecules. On the other hand, we showed that chlorination in the constant domain, far from the binding interface, of Rituximab Fab also increased the affinity significantly (up to 17-fold). Our results showed that antigen binding is tunable with the halogenation in and out of the binding motifs.