Round Form Research Articles

On typological characteristic of funerary architecture of uzbekistan in the ancient period

The funerary architecture of Uzbekistan of the ancient period, the development of which was directly related to the changes in religious beliefs of ancient peoples, went the evolutionary path - from simple underground crypts-nauses to monumental above-ground structures. In each historical and cultural region of Central Asia, the funerary architecture was characterized by its own distinctive features. In Bactria these were the single-, double- and multi-chamber above-ground tombs, in Chach - the buildings of round (with a rectangular chamber inside) and yurt-shaped forms, in Fergana - the mugkhonas and kurums, in Khorezm - the mausoleums of a cross-shaped configuration.

Влияние энергомеханической обработки на структурно-механические свойства Co – Cr – Mo сплавов, полученных методом искрового плазменного спекания

We studied the effect of energy mechanical pre-treatment (EMT) of the initial (Co – Cr – Mo) alloy powders in a vortex layer of ferromagnetic bodies on the structural-mechanical properties of products obtained by spark plasma sintering (SPS). To study the properties of powder and compact samples, the methods of scanning electron microscopy (SEM), optical microscopy, determining the bending strength and microhardness on the Vickers scale were used. It was shown that the EMT of powders for a short time (1 – 3 min) leads to intense plastic deformation of a large part of the initial rounded particles, forming irregular- and plate-shaped particles with high surface roughness. As a result, EMT has a positive effect on spark plasma sintering process of powder, makes it possible to obtain a densely sintered material with a low-porous structure. It was found that the sample pre-treated under EMT for 3 min is compacted during sintering process to a high level (relative density reached 98.3 %) and its mechanical properties has greatly improved (microhardness and bending strength are 16 % and 14 % respectively higher than the sample without pre-treatment). The improvement of structural and mechanical properties of sintered specimens pre-treated under EMT is a result of intensification of diffusion mass transfer processes during sintering due to the plastic deformation of material, change in the shape, surface state of the powder particles and an increase in the total contact area between them. High surface roughness and deviation of particles from the round form lead to a decrease in the radii of curvature of their contact surfaces and, consequently, to an increase in the Laplace forces value, which play a dominant role in the diffusion mass transfer processes during sintering.

Influence research of temperature heat treatment on the microstructure of alumina ceramics

The JSC "URIR named after A. S. Berezhnoy" developed and introduced the technology of highly refractory alumina extra-dense ceramics. It is known that, the structure and properties of alumina ceramics in many cases depend on the temperature of its heat treatment, the holding time at the final temperature, the thermal unit, and a number of other factors. In order to study the processes of structure formation during of heat treatment the microstructure of alumina ceramic samples of two compositions (composition 1 with a moisture content of 30 %, as well as with dispersing and hardening additives, and composition 2 with a moisture content of 20 % only with dispersing additive) which were made by slip casting aqueous alumina slips based on reactive alumina α–from with Al2O3 content over 99 %, specific surface ~ 9 m2/g by electron microscopic analysis was studied. It was established that, after heat treatment at 1000 °C the beginning of sintering and recrystallization of corundum grains are observed, after heat treatment at 1200 °C take place packing of structure and recrystallization of α–Al2O3. After firing at 1400 °C the microstructure of samples composition 1 is represented to a large extent by crystals of tabular corundum with a particle size ~ 0.5—5.5 μm, predominant — ~ 2.5—3.0 μm. After firing at 1400 °C the microstructure of samples composition 2 is represented — by individual particles of a rounded and oval form with a size of ~ 0.5—3.5 μm, predominant — ~ 1.5—2.0 μm which are interconnected by intercrystalline layers. The microstructure of alumina ceramic samples of both compositions after firing at 1500 °C is similar and is composed of recrystallized corundum grains with a size of ~ 0.5—5.5 μm, predominant — ~ 1.5—2.0 μm, among which there are also larger α–Al2O3 grains, with a size of ~ 2—8 μm. After firing at 1580 °C the microstructure of samples is represented by a dense fine-grained structure of well-formed practically defect-free corundum grains, with a size of ~ 0.5—3.0 μm, among which grains of ~ 5—10 μm.

Effects of amount of added water on red yeast rice production using Korean soft rice variety “Hangaru”

Abstract We aimed to develop an efficient process for producing red yeast rice (RYR) with different rice cultivars (Samkwang: used for cooking and Hangaru: used for processing) and amounts of added water (0–100%). Our analyses showed that Hangaru rice had a round starchy form with 18.62% amylose content, and Samkwang rice exhibited an angular starchy form with 15.29% amylose content. The in vitro enzymatic hydrolysis ratio was higher for Hangaru RYR (20.92–24.28%) than for Samakwang RYR (10.97–15.91%) with different amounts of water added. Hangaru RYR showed the highest color value with 60% added water; however, Samkwang RYR highest color value was at 40% added water. The total content of monacolin K was the highest (749.34 mg/kg) for Hangaru RYR treated with 60% added water. These results suggest that Hangaru rice supplemented with 60% water is the most suitable for producing RYR.

FUNCTIONAL MORPHOLOGY OF BIRDS’ BLOOD LEUKOCYTES

The present research was carried out in an attempt to identify the problems associated with the morphofunctional analysis of vertebrate animal’s leukocyte blood cells. For this blood samples of four age groups chickens (Gallus gallus L.) were collected and analysis was carried out as per the recommendations of the International Council for Standardization in Hematology for the identifying morpho-physiological characteristics of leukocytes of peripheral blood of birds. Results of the current study were based on the sample of early postnatal ontogenesis based on the analysis of high-resolution color microphotographs taken by the method of light-optical microscopy. Results of the current study revealed that the cells have the well-designed of all granular leukocytes typical "eosinophilic" nucleus with two segments. Sometimes cells contain polysegmental nuclei that are eccentrically located. Further, in contrast to heterophils, the eosinophilic nucleus has well-expressed contours, formed by irregularly shaped chromatin blocks with an optically denser structure. There are also eosinophils with stick-nuclei. The smallest blood granulocytes of the birds are basophils. Basophils differ in structure slightly basophilic color cytoplasm with intensively basophilic granules of rounded or other forms of different size. The sizes of granules in basophils are smaller than the other types of granular leukocytes. Thus, based on the analysis of qualitative color microphotographs of white blood cells of chickens of neonatal ontogenesis performed by optical microscopy, the differential morpho-physiological markers of leukocytic cells of peripheral blood of birds were marked and characterized.

Мікроскопічне дослідження біосумісності зразків з вмістом мультипотентних мезенхімальних стромальних клітин жирової тканини в умовах експерименту

The purpose of the study was to investigate the biocompatibility of samples containing multipotent mesenchymal stromal cells of adipose tissue to replace bone defects. Material and methods. The study was conducted at Bukovina State Medical University, Chernivtsi, Ukraine. Adipose tissue samples were obtained from the neck of 60 experimental animals (white Wistar rats). We selected 4 samples for the toxicological experiment, which allowed to establish the direct influence of factors in the contact of implantation material at the cellular level. Sample № 1 - Multipotent mesenchymal stromal cells of adipose tissue, which underwent osteogenic differentiation; № 2 - Multipotent mesenchymal stromal cells of adipose tissue with osteogenic differentiation with the addition of platelet-enriched blood plasma; № 3 - “Kolapan” with applied tissue culture of Multipotent mesenchymal stromal cells of adipose tissue cells, which underwent osteogenic differentiation; № 4 - "Kolapan" + Multipotent mesenchymal stromal cells of adipose tissue + platelet-enriched plasma. Multipotent mesenchymal stromal cells of adipose tissue were obtained by grinding adipose tissue of rats in 0.1% collagenase 1A [14]. The study of biocompatibility by cell culture in vitro was performed in accordance with the Working Instruction № 04/2013-VL. The cultures were investigated by the explantation method in a plasma clot in Karelian vials. In order to standardize the nature of growth, their zones were classified into compact, reticular and migrating cells of growing fibroblastic tissues. To assess the probability of the obtained results of the study we used a variation-statistical method of analysis using Microsoft Excel. Statistical calculation of the results of clinical and laboratory studies was carried out according to conventional methods. Results and discussion. Microscopic examination of the surface of samples with culture of fibroblasts showed their satisfactory adhesion on the tooth surface after 5 days of cultivation. In the study of sample № 1 (Multipotent mesenchymal stromal cells of adipose tissue, with osteogenic differentiation), it was noted that the structure of the cells acquired a rounded and oval shape, which indicated their destruction and damage. On the 5th day of observation, cells with numerical intussusception and processes were observed during visual examination of sample № 3 (“Kolapan”, with applied culture of Multipotent mesenchymal stromal cells of adipose tissue). In the study of samples № 4 (Multipotent mesenchymal stromal cells of adipose tissue + platelet-enriched plasma + "Kolapan") on the 5th day of research, signs of growth were manifested by migration of fibroblastic elements that had a spindle-shaped and polygonal shape, with the formation of the primary zone due to strands. On the 7th day of cultivation in experimental samples № 2, № 3, № 4 there was the formation of three growth zones: compact - from cells of polygonal and spindle-shaped form; reticulate - from strands and bundles of cells that were located reticulate and areas of single migrating elements of spindle-shaped. External characteristics and cell growth surface did not differ from control samples. On the 10th day of cultivation in the experimental samples, as well as in the control, the areas of compact and reticular growth zone and the zone of migrating fibroblasts were increased. At the same time, tissue-like growth of cells was observed. Visualization of compact and stack-like zones of the studied experimental samples revealed signs of the beginning of degenerative changes, which was characterized in the form of rounding of the shape and vacuolation of cells. This trend was most pronounced in samples № 2 and № 4. Conclusion. Thus, tissue equivalents of bone tissue based on Multipotent mesenchymal stromal cells of adipose tissue can be candidates for use in regenerative medicine, and studies of their application in experimental animals will provide an opportunity to expand the understanding of the characteristics of Multipotent mesenchymal stromal cells of adipose tissue in order to optimize their further clinical application and implement new approaches in different areas of dentistry

Perceptions of interdisciplinary bedside rounds by head nurses in Flanders: a cross-sectional exploration

ABSTRACT Objectives Interdisciplinary bedside rounds is gaining ground as a method to improve patient centredness and involvement, quality of care and team collaboration. An exploratory study was conducted in Flemish hospitals to (1) map and (2) examine the current form of rounds and the extent to which these were bedside, patient and family participatory and interdisciplinary. Methods In February 2020, a quantitative cross-sectional self-reporting web-based survey was conducted in 23 hospitals in Flanders, 213 head nurses of 213 wards completed the survey. A self-reporting 19-item questionnaire was developed in Lime Survey®. The questionnaire contained a mix of closed-ended questions an open-ended questions. The data were analysed using SPSS 26.0. Results Most of the wards in Flanders organise a form of daily rounds at the bedside. In only half of the wards these rounds are organised at a fixed time. The rounds most often include a physician and a nurse. Other disciplines are rarely actively involved. Only a minority of wards uses checklists, structures or protocols to standardise the rounds. The majority of the wards reports that patients (and family) get sufficient time to ask questions and say they are actively stimulated to do so. Conclusion In current practice, most rounds are (partially) bedside, open for patient and family participatory and often include only a physician and a nurse. However, these elements of interdisciplinary rounds are not yet well integrated and vary strongly amongst ward. Most rounds should be considered as an extended form of physician rounds, rather than being interdisciplinary.

КРУГЛІ ПЛИТИ НА ПРУЖНІЙ ОСНОВІ ЗІ ЗМІННИМ КОЕФІЦІЄНТОМ ПОСТЕЛІ

The paper considers the application of the analytical method - the method of direct integration - to the calculation of building structures in the form of round and annular plates and slabs lying on a continuous variable elastic basis. The application of the proposed approach allowed to obtain solutions of a wide class of problems, the mathematical summary of which are differential equations with variable coefficients or systems of such equations, and at the same time to evaluate the possibilities and accuracy of calculation of finite elements. The base reaction is described by the Winkler model with a variable bed ratio. With respect to the bending of round and annular plates, formulas for the function of deflections and its derivatives, transverse force and bending moments are obtained. The method is applicable under any given boundary conditions on the contours. The calculation is reduced to determining from the given boundary conditions of the unknown constants of integration and numerical realization of the obtained solutions. The found formulas of the general form are transformed for practically important case when the factor of a bed and loading have the form of polynomials. It is shown that in this case dimensionless fundamental functions are represented by static series. To calculate the coefficients of static series, the corresponding recurrent relations are derived. The calculations show that the discrepancy in the results of the calculation of the deflections of the FEA and the author’s method (AM) is insignificant (not more than 1%), and the results of the calculation of radial and circumferential moments differ significantly, and this difference sometimes reaches 12-14%. However, when the grid is condensed in the circumferential direction, the picture changes, there is a convergence of the results obtained by two methods. This indicates the inaccuracy of the finite element analysis performed on the basis of automatic partitioning of the finite element grid. And this, in turn, leads to "blind" reinforcement of reinforced concrete slabs, in which it is possible, both re-reinforcement of the structure and its insufficient reinforcement.

A note on sasanian-buddhist object of Gyeongju National Museum

A note on sasanian-buddhist object of Gyeongju National Museum
 Although Korean and late Sasanian texts are silent about mutual relations, archaeological evidences provide a different perspective. This paper deals with an object known at Gyeongju National Museum of the Republic of Korea. The loop was discovered in Bunhwangsa Buddhist Temple in Geun-jik (Gyeongju) region in 2001. Gyeongju’s loop includes a round form made of clay, with a pearly chain (running) in the border and two birds (ducks most probably) appearing in the center of the motif while they are trying to hold a stalk of a herb. Many scholarly works have been published about it and interpreted it as the ‘tree of life.’The author believes that this herb (as distinct from a plant) is a sacred lotus. In fact, the birds try to hold it in their beaks. So, an expert creator of the object used known Sasanian artistic elements on the one hand and combined them with a famous Buddhist element on the other hand. It ispossible the creator attempted to immortalize his work with this sacred lotus: in a Buddhist temple, only such an element was allowed to be introduced.

(Invited) Micro-Electrochemistry of Pit Initiation at Non-Metallic Inclusions of Stainless Steels and Roles of Alloying Elements in Improving Corrosion Resistance

A micro-electrochemical system for in situ high-resolution optical microscopy was developed and applied to the real-time observation of pit initiation at MnS inclusions in Type 304 stainless steel in NaCl solutions. Metastable and stable pits were found to be initiated at the MnS/steel boundaries during potentiodynamic polarization. After polarization, it was confirmed that deep trenches were generated at the boundaries. Therefore, metastable and stable pits were determined to be initiated in the trenches. From the real-time observation, it was found that the initial rounded form of metastable and stable pits became polygonal in shape within 1 s. After that, the dissolution proceeded in the depth direction with no change in the appearance of the pit as observed externally. In the case of the metastable pitting, the duration of this stage was approximately 1.5 s, and then the pit repassivated, and the polygonal metastable pit remained. The in-depth growth stage for stable pitting was relatively longer (approx. 3.5 s), and the pit grew deeply into the steel matrix and wrapped beneath the inclusion, leading to the formation of a large occluded cavity, in which the corrosivity considerably exceeded the critical conditions for autocatalytic pit growth. The anodic dissolution behavior of CrS, TiS, and Ti4C2S2 inclusions was compared with that of MnS. The dissolution potential of CrS inclusions was in the transpassive region of stainless steels. Stable pits were initiated in this potential region. In contrast, TiS and Ti4C2S2 inclusions did not dissolve in the passive or the trans-passive regions of stainless steels, and no pits were initiated at these inclusions in NaCl solutions. The calculations made from the potential-pH diagrams for CrS, TiS, and Ti4C2S2 systems indicated that Cr-oxide or Ti-oxide enriched surface films would form, and this was confirmed by surface analysis. The Cr-oxide or Ti-oxide enriched layers on the inclusions inhibited the anodic dissolution of the inclusions in the passive or trans-passive regions of stainless steels. In contrast, MnS inclusions dissolved in NaCl solutions, and pits were initiated at the inclusions. While MnS inclusion surfaces were covered by Mn-oxides, the corrosion resistance of Mn-oxides was not sufficient to prevent inclusion dissolution and subsequent pit initiation. The oxide enriched surface layers on the sulfide and carbo-sulfide inclusions were shown to significant enhance pit initiation resistance at the inclusions. In addition to the above findings, the roles of the addition of Ce and Mo were studied. From the results of micro-scale polarization, thermodynamic calculations, and scanning electron microscopy, it was suggested that the Ce3+ ions inhibit trench formation at the inclusion/steel matrix boundary, resulting in improved pitting corrosion resistance at sulfide inclusions. And also, the active dissolution rate of the steel was suppressed by Mo alloying. This suggests that, even after trenching at high potentials, Mo alloying inhibits the initiation of pitting inside the trenches.

Characterization comparison of bottom ash and fly ash during gasification of agricultural residues at an industrial-scale gasification plant – Experiments and analysis

In this study, the characterization of the fly and bottom ashes from an industrial gasification plant for biomass syngas production were investigated and compared in terms of particle size distribution, chemical composition, fusibility, mineralogy and morphology. The experimental results indicated that the characteristic particle sizes of the bottom ashes from gasifier were larger than those of the fly ashes from cyclone or sprayer. By contrast, the fly ashes contained higher contents of potassium, sulphur and chlorine. The base-to-acid ratio (Rb/a) values for those fine fractions in the bottom residues and the fly particles from cyclone were in high deposition range (Rb/a > 1.0) while that for the slags in the bottom ash or the fly particles from sprayer was in medium deposition range (0.5–1.0). As regards the fouling index (Fu), the value of cyclone ash (Fu = 41.2) was higher than those of the other ashes, reflecting its relatively higher deposition tendency on heat transfer surfaces. Besides, the fusion temperatures of the fly ashes were lower than those of bottom ashes. The rounded forms of fly particles could be regarded as the indicative of ash melting. Comparison of thermograms indicated that the bottom ash contained more organics than fly ash, thus explaining its relatively higher weight loss during ash fusion. In practice, more attention should be paid on the rational control of operating temperature, which could relieve the occurrence of ash deposition/agglomeration to some extent.

Effect of 940 nm Diode Laser as Adjunct Treatment to Mechanical Instrumentation on Root Surface Gingival Fibroblast Adhesion in Periodontally Compromised Extracted Teeth : An in vitro Study

Introduction: Mechanical debridement of diseased root surfaces produces a smear layer that encompass microorganisms and residual cementum which may interfere with periodontal healing and regeneration of connective tissue attachment. Accordingly, this study aimed to determine impact of 940nm diode laser on adhesion of fibroblasts to root surface of extracted teeth from patients with chronic periodontitis. Methods: Twenty extracted single-rooted teeth with hopeless prognosis were collected and debrided with hand curettes. Afterward, two specimens were obtained from each tooth by splitting them with a sterile diamond disk. Samples were submerged in fibroblast suspension and randomly divided into two groups. Group A comprised of 20 specimens subjected to scaling and root planing only and group B included 20 specimens which received SRP and and 940 nm diode laser irradiation. The adhesion of fibroblasts was investigated by MTT and cell morphology was assessed with scanning electron microscopy (SEM). Results: The extent of adhesion was higher in group B compared with group A, though this difference was not statistically significant. In the laser group, fibroblast cells showed more elongated morphology and a smaller number of rounded forms was found. But no significant difference was observed between the two groups. Conclusion: A diode laser with a wavelength of 940 nm has a negligible effect on adhesion of fibroblasts to the root surface of teeth extracted because of chronic periodontitis

The Nonapeptide RWQWRWQWR: A Promising Molecule for Breast Cancer Therapy

AbstractThe palindromic nonapeptide H‐1RWQWRWQWR9‐NH2 (LfcinB (21–25)Pal) was synthetize and scaled following the good manufacturing practices (GMP) guidelines to obtained batches up to 1 g of pure peptide which evidencing their synthetic viability. Its cytotoxic effect was tested against breast cancer cell lines MDA‐MB‐231 and MCF‐7 and was dependent on concentration against both. The IC50 values were 135 μM and 66 μM, respectively. Against MCF‐7 the peptide exerts its greater cytotoxic effect at 135 μM, diminishing their cell viability to 21%. Furthermore, the palindromic peptide did not exhibit a significant cytotoxic effect against the nontumorigenic cells MCF‐12, BMEC (bovine mammary epithelial cells) or fibroblast, which confirms its selectivity. The cancerous cells treated at 135 μM for 2 h exhibited morphological changes like cellular shrinkage and rounded forms. Trough flow cytometry assays we evidence that 73% of the events were related to late apoptosis, and cells that exhibited mitochondrial membrane depolarization also had an increase in the relative expression of caspase‐3. Our results suggest that the LfcinB (21–25)Pal peptide has a cytotoxic effect against MCF‐7 mainly through apoptotic events which makes it a promising candidate for therapeutic agent.

The use of mineral interfaces in sand-sized volcanic rock fragments to infer mechanical durability

The use of mineral interfaces, in sand-sized rock fragments, to infer the influence exerted by mechanical durability on the generation of siliciclastic sediments, has been determined for plutoniclastic sand. Conversely, for volcaniclastic sand, it has received much less attention, and, to our knowledge, this is the first attempt to make use of the volcaniclastic interfacial modal mineralogy of epiclastic sandy fragments, to infer mechanical durability control at a modern beach environment. Volcaniclastic sand was collected along five beaches developed on five islands, of the southern Tyrrhenian Sea (Alicudi, Filicudi, Salina, Panarea and Stromboli) from the Aeolian Archipelago, and one sample was collected near the Stromboli Island volcanic crater. Each sample was sieved and thin sectioned for petrographic analysis. The modal mineralogy of the very coarse, coarse and medium sand fractions was determined by point-counting of the interfacial boundaries discriminating 36 types of interfaces categories, both no-isomineralic and/or no iso-structural (e.g., phenocrystal/glassy groundmass or phenocrystal/microlitic groundmass boundaries) and iso-mineralic interfaces, inside volcanic lithic grains with lathwork and porphyric textures. A total of 47,386 interfacial boundaries have been counted and, the most representative series of interfaces, from the highest to the lowest preservation, can be grouped as: a) ultrastable interfaces, categorized as Pl (Plagioclase)/Glgr (Glassy groundmass) > > Px (Pyroxene)/Glgr > > Ol (Olivine)/Glgr > > Op (Opaque)/Glgr > > Hbl (Hornblende)/Glgr> > Bt (Biotite)/Glgr > > Idd (Iddingsite)/Glgr > > Rt (Rutile) / Glgr; b) stable interfaces, categorized as Pl/Migr (Microlitic groundmass) > > Op/Migr > > Px/Migr > > Ol/Migr; c) moderately stable interfaces, categorized as Op/Px > > Op/Hbl > > Px/P > > Ol/Pl> > Bt/Op; and d) unstable interfaces, categorized as Pl/Pl > > Px/Px > > Ol/Ol > > Op/Op > > Hbl/Hbl > > Bt/Bt. Grains, eroded from the volcanic bedrock, if affected solely by abrasion, developed a rounded and smoothed form, with prevailing no-isostructural interfaces such as Plagioclase/Glassy groundmass, Pyroxene/Glassy groundmass and Olivine/Glassy groundmass interfaces. Grains that during transport suffered fracturing and percussion have a sharp and angular form: these combined transport mechanisms produce mainly volcanic sandy grains with iso-structural interfaces, such as Pl/Pl, Px/Px, Hbl/Hbl, and, to a lesser extent, Bt/Op and Bt/Glgr interfaces.

Radiographic Analysis on the Distortion of the Anatomy of First Metatarsal Head in Dorsoplantar Projection.

Background: The diagnostic of flat and crest-shaped of first metatarsal heads has been associated as an important risk factor for hallux deformities, such as hallux valgus and hallux rigidus. The rounded form of the first metatarsal head on the dorsoplantar radiograph of the foot has been believed to be associated with the development of hallux valgus. Purpose: The aim of this study was to clarify the effect of tube angulation on the distortion of first metatarsal head shape, and verify the real shape of the metatarsal head in anatomical dissection after an X-ray has been taken. Materials and Methods: In this prospective study at Universidad Complutense de Madrid, from December 2016 to June 2019, 103 feet from embalmed cadavers were included. We performed dorsoplantar radiograph tube angulation from 0° until 30° every 5° on all specimens; then, two observers verified the shape of the first metatarsal head in the radiographs and after its anatomic dissection. Kappa statistics and McNemar Bowker tests were used to assess and test for intra and interobserver agreement of metatarsal shape. Results: We calculated the intraobserver agreement, and the results showed that the first metatarsal head is distorted and crested only when the angle of the X-ray beam is at 20° of inclination (p < 0.001). The interobserver agreement showed good agreement at 0°, 5°, 10°, 20°, and 25° and was excellent at 30° (p < 0.001). Conclusion: All of the studies that we identified in the literature state that there are three types of shapes of the first metatarsal head and relate each type of head to the diagnosis of a foot pathology, such as hallux valgus or hallux rigidus. This study demonstrates that there is only the round-shaped form, and not three types of metatarsal head shape. Therefore, no diagnoses related to the shape of the first metatarsal head can be made.

Designing the Future: Past and Future Trajectories for Design Innovation Research

Designing the Future: Past and Future Trajectories for Design Innovation Research

Study on the impact of different pier structures on navigable flow conditions

The navigable clearance scale is a key factor in the selection of bridge type schemes on urban navigable rivers, especially in the case of limited clearance, the restriction of pier size and shape on navigation. In this paper, the impact of different pier structures on navigable flow is analyzed through the two-dimensional flow mathematical model simulation of new bridge section of a river. The results show that the shape optimization of square pier chamfer can reduce the transverse velocity of navigable flow; and the larger size of pier, the greater transverse velocity of navigable waters. Furthermore, the transverse velocity of the navigable flow is the smallest on the condition of the same width but round form of head pier structure. The new design can effectively solve the contradiction between bridge navigation and landscape construction on urban navigable river, and provide a variety of options for bridge construction.

On the machining behavior of carbon fiber reinforced polyimide and PEEK thermoplastic composites

AbstractPolyimide (PI) and polyetheretherketone (PEEK) are superior high‐performance thermoplastics being extensively used in the fields of fiber‐reinforced polymer composites. However, there is very limited literature addressing the machining behavior of the PI and PEEK composites. The present paper aims to conduct a comparative study into the machining characteristics of these two representative high‐performance thermoplastic matrix composites under varying cutting conditions. Machinability aspects of the carbon/PI and carbon/PEEK thermoplastic composites were evaluated in terms of drilling forces, machining temperatures, delamination damage, surface morphologies, hole dimensional accuracy and tool wear. The results indicate that the carbon/PEEK composites generally show a much poorer machinability than the carbon/PI composites in terms of higher drilling forces, higher cutting temperatures, larger delamination extents and excessive tool wear. Since the carbon/PEEK composites exhibit certain ductility leading to the continuous chip formation, the cut hole surface morphologies and dimensional accuracy are much better than those gained in the carbon/PI composites. Both the cutting speed and the feed rate affect significantly the drilling forces and the resulting delamination damage. The fundamental wear mechanisms of drilling carbon/PI composites are abrasion wear in the form of edge rounding and slight chip adhesion, while for the carbon/PEEK composites, they are abrasion, serious chip adhesion because of the high drilling temperatures promoted at the drill‐work interface and catastrophic failures of coating peeling and edge fracture.

Enhancing the clinical competence of postgraduate students in periodontology: design and implementation of multidisciplinary grand rounds

Recently the model of cultivating stomatology talents for postgraduate education in China is primarily specialized education. The aim of the present study was to construct a multidisciplinary grand rounds series based on presentation and commentary for diagnosis and treatment plan of clinical cases, in order to improve the clinical competence of postgraduate students from various dental disciplines for resolving the clinical problems. The grand rounds series was designed for postgraduate students of periodontology, with the combination of the advantages of the international dentistry education experience and Chinese characteristics. This study focused on designing and exploring the multidisciplinary grand rounds series based on complicated periodontal clinical cases, and also on analyzing and evaluating the effectiveness of the series by questionnaire investigation for both teachers and students. The results of the preliminary investigation showed that postgraduate students had positive view on the form and content of the teaching rounds. However, more analysis is needed for further evaluation.

Exploring pathophysiology of COVID-19 infection: Faux espoir and dormant therapeutic options

COVID-19 virus structural components: The 2019-nCoV, also called SARS-CoV-2, was first reported in Wuhan, China in December 2019. The disease was named Coronavirus Disease 2019 (COVID-19) and the virus responsible for it as the COVID-19 virus, respectively, by WHO. The 2019-nCoV has a round, elliptic or pleomorphic form with a diameter of 60–140 nm. It has single-stranded RNA genome containing 29891 nucleotides, a lipid shell, and spike, envelope, membrane and hemagglutinin-esterase (HE) proteins.