Plane Of Section Research Articles

STYLISTIC MEANS OF IMPLEMENTING THE IDEA OF THE WORLD’S IRIDESCENCE IN PH.K. DICK’S “UBIK” IN THE CONTEXT OF TRANSLATION TRANSFORMATIONS

The article deals with the formation means of the idea of the world’s iridescence or illusiveness, its stylistic and translation aspects within the textual framework of Ph.K. Dick’s novel “Ubik” and its translat- ed version in Ukrainian. The relevance of the study is defined by general scarcity of current enquiries highlighting stylistic means of moulding the idea of the world’s iridescence in science fiction as well as translation methods of delivering it from English to Ukrainian. The purpose of this scientific inquiry is to identify the stylistic devices that play a role in the delinea- tion of ways in which reality may be reduced to tatters in comparison with a coherent state of things and to pinpoint the translation techniques of rendering the related contexts from English into Ukrainian. The top- icality of the study is determined by the paucity of relevant research focusing on the kernel of the prevail- ing theme in Dick’s “Ubik”, namely illusiveness of reality, and translation techniques and transformations that help adequately deliver the significant sequences from English into Ukrainian. It is argued that the idea in question being the core of the prevailing theme in Dick’s “Ubik” is at- tained by means of incorporating several ontological planes represented by mental constructs, or reali- ties, focalised through the perceptions and personalities of different characters of the novel. Contextu- al and text interpretation analyses enabled the authors to determine and interpret those semantic domi- nants that underpin the formation of the world’s iridescence effect in the novel, namely: “alternate reali- ties”, “dream as a variant of reality”, “changes in time and space”, “changes of forms of consciousness and existence”. It has been proven these dominants’ diegetic interrelation. The idea of the world’s iridescence in the novel is brought about by the literary work’s fluctuating plot convolutions stemming from seemingly incoherent planes of different sections of the novel: a mosaic of the primary diegesis together with several hypo-diegeses comes across as a kind of an ontic hazy maze building up to an overall effect of the world’s fluidity and oscillation. The method of stylistic analysis was applied to interpret stylistic phenomena inherent in the novel in relation to their contribution to the studied idea as those were found functioning in the relevant textu- al microcontexts and enhancing the aforementioned semantic dominants. It was esti mated that expres- estimated that expres- sive means and devices of stylistic syntax constitute four fifths of the whole researched corpus of units, thus playing a major role in the formation of the idea of the world’s illusiveness (those include aposiopesis, rhetoric questions, asyndeton, and nominative sentences) while expressive means and stylistic devices of stylistic semasiology prove much less numerous, accounting for a fifth of the units analysed (presented by metaphors, epithets, similes, antitheses). Among the typical translation methods, instrumental in the rel- evant textual sequences in “Ubik”, a share of lexical and semantic transformations equals 60.2% of the re- searched sets of translation counterparts, with modulation and specification being the dominant ones and logical synonymy, calquing and lexical compensation trailing behind. Grammatical transformations com- pose nearly two fifths (39.8 %) of the researched body of units, the most efficient ones being substitution and word order change. The results of the study enabled understanding the interaction mechanism of semantics of the leit- motif of a literary work, its stylistic representation and translation solutions of its delivery from English into Ukrainian. We envisage the prospects for further research in studying linguistic aspects of cross-cultural conveying symbolic significance of recurring narrative elements.

Technical note: Effects of chemical, radiational, and thermal treatment of bone tissue on material stiffness and anisotropy.

We evaluated the effects of four treatments for pathogen inactivation in bone tissue (ethanol storage, formalin fixation, gamma irradiation, and heat treatment via autoclave) on stiffness and anisotropy values in bone samples. Cortical bone samples from the humerus of 14 bovine specimens were subjected to Knoop microindentation analysis in longitudinal and transverse planes of section and four indenter orientations within each section. From each specimen, individual samples were assigned to one of five treatment conditions: 50% ethanol-saline solution, formalin immersion, gamma irradiation, autoclave, and buffered saline (controls). Each sample was microindented 100 times and the resultant stiffness data were analyzed by a resampled factorial analysis of variance. First- and second-order interactions as well as main effects of indenter orientation, treatment, and specimen were significant for both transverse and longitudinal sections, with the sole exception that indenter orientation-treatment interaction was nonsignificant for longitudinal sections. Interaction plots reveal that thermal (autoclave) and irradiation treatments depress stiffness values the most, while patterns of indentation stiffness at different orientations are relatively unaffected. Patterns of anisotropy are relatively unaffected by preservative treatments, but elastic modulus changes are consistent and unambiguous. Formalin and ethanol treatments are most comparable to controls and represent the best preservative media for mechanical testing. These options, however, are likely to be the least effective for ensuring the inactivation or sterilization of potentially contaminated samples.

Study on eccentric compressive performance of circular double skin concrete filled steel tube connected by thread through inside lining tube

Connection method of lengthening the steel tube of circular hollow sandwich concrete-filled steel tube by inside lining tube and thread is proposed. Twelve circular hollow sandwich concrete filled steel tubular beam-column connected by thread through inside lining tube are designed and fabricated using the length of the thread along the axial direction, the working height of the thread, and the position of the thread as parameters; In addition, one unconnected specimen and two welded specimens also are designed and fabricated to conduct controlled experimental research. The test phenomena and failure modes, axial compressive load-compression curve, axial compressive load-lateral deflection curve, and axial compressive load-strain in steel tube curve, as well as bearing capacity, strength reservation, deflection curve shape, lateral stiffness, ductility and plane section assumption are analyzed. The research results indicate that, within the parameter range studied, the thread connection through inside lining tube is reliable before tripping, and the experimental phenomenon of specimens connected by thread is basically consistent with that of the unconnected specimens. The axial compressive load-compression curve and axial compressive load-lateral deflection curve of all specimens can be approximately divided into elastic stage, elasto-plastic stage, and descending stage. The peak load of all specimens is relatively close, while although experiencing almost the same loading process, the strength reserve of the specimens connected by thread is insufficient. During the entire loading process, the shape of the deflection curve of all specimens is close to the sine half wave curve, and the distribution of longitudinal strain in the steel tube along the height of the middle cross-section basically conforms to the plane section assumption. Calculation method for bearing capacity of circular hollow sandwich concrete filled steel tubular beam-column connected by thread through inside lining tube is suggested.

Analysis of the left atrial appendage function by intracardiac echocardiography in patients with atrial fibrillation

Abstract Introduction Intracardiac echocardiography (ICE) is frequently performed during catheter ablation procedures in order to guide the transseptal puncture and has been recently used to evaluate the morphology of the LAA. Purpose The objective of this study was to evaluate the feasibility of using an ICE catheter placed in the coronary sinus (CS) to delineate the LAA function during catheter ablation for atrial fibrillation. Methods We included 21 consecutive patients (age 62±9 years, 5 women, 6 paroxysmal AF) who underwent catheter ablation for AF. An 8-Fr phased-array ICE catheter was used to obtain images of the LAA, while in sinus rhythm. The LAA was visualized with the ICE probe placed sequentially in the left atrium (LA, Figure A), with the ultrasound section plane parallel to the long axis of the left ventricle (LV), and in the CS, with the ultrasound section plane perpendicular to the LV long axis (Figure B). LAA emptying flow velocity, and LAA fractional area change (FAC) were used to evaluate LAA function. There were no procedural complications. Results ICE imaging was possible in all cases. The LAA peak flow velocity was similar when the ICE catheter was placed in the LA and in the CS (64±7 cm/s and 62±5cm/s respectively, P=NS). The LAA FAC was significantly lower when the ICE catheter was placed in the CS when compared to an LA location (14±6% vs 36±14%; P<0.001). The LAA FAC measured from the LA correlated with the mitral annular plane systolic excursion while the LAA FAC measured from the CS did not. Thus, LAA contraction in a plane perpendicular to the LV long axis is independent of the LV longitudinal contraction. These results suggest that in our patient group most of the LAA contraction was due to the longitudinal movement of the LV base during systole and diastole. Conclusions Imaging of LAA using an ICE probe positioned in the LA and CS was feasible in all cases. The LV longitudinal contraction appears to impact the LAA function.

Seismic behavior of resilient concrete column-base connection with SMA bolts and RSPs

This paper presented a novel resilient concrete column-base connection with shaped memory alloy (SMA) bolts and rectangular slotted plates (RSPs) to achieve the demountable and recoverable capabilities in precast concrete columns. Quasi-static tests were conducted on one monolithic and three resilient concrete connections to investigate the effects of RSP number and yield strength on seismic behavior. Results showed that the resilient connection with both flange and web RSPs had superior lateral capacity, ultimate drift ratio, and energy dissipation compared to the monolithic connection. The resilient connection also exhibited minimal concrete damage and smaller residual deformation. However, low-yield-strength flange RSPs significantly reduced lateral capacity, initial stiffness, and energy dissipation, which should be considered in engineering design. Additionally, adjustment coefficients for rocking interface rotations were determined from digital image correlation (DIC) data using a fitting method. A formula was proposed to predict the flexural capacity of resilient specimens, assuming a plane section in the compression zone. The predictions closely matched the test data, with differences within 10 %, demonstrating the formula's effectiveness. The length, diameter, and material yield strength of the anti-shear steel bar (ASB) had a significant impact on the shear capacity of the interface.

Investigating the mechanism of time dependent evolution of vertical graphene nanowalls

This work presents a time dependent multistage growth model for vertical graphene nanowalls (VGN). Factors mediating growth of VGN in both vertical and spatial direction at different stages were discussed. VGN films were deposited on Si (100) substrate using Radio Frequency Plasma-Enhanced Chemical Vapor Deposition technique by increasing the deposition time systematically for 15 min, 30 min, 60 min, 120 min, and 240 min, respectively. Scanning electron microscopy was carried out in both planar and cross section view to confirm the growth of VGN and quantification of its height. Atomic force microscopy was used to characterize the spatial growth of VGN. Raman scattering and in-plane GIXRD measurements were carried out to characterize the microstructure of VGN, which unveils that the strain relaxation and defects annihilation followed by increase in average crystallite size plays crucial role. Eventually, a schematic diagram was presented for time dependent evolution of VGN at different stages.

Study on bending performance of prefabricated glulam-cross laminated timber composite floor

Abstract The glulam-cross laminated timber (CLT) composite floor is a type of prefabricated composite floor that integrates glulam beams and CLT slab into a unified structure using shear connectors. To investigate the bending performance of the glulam-CLT composite floor, the bending test was conducted on a full-scale composite floor under static load. The study comprehensively analyzed the failure mechanism, load–deflection behavior, interface slip and strain distribution of the glulam-CLT composite floor. The test results of the composite floor indicated that the failure mode was tensile fracture of the wood beam at the bottom. As the load increased, the deflection deformation of the mid-span beam exceeded that of the edge beam. When the load reached its ultimate limit, the deflection deformation of the mid-span beam increased by 14.4% compared to the edge beam. In the early loading phase, the strain distribution of the composite section satisfied the assumption of a plane section. However, the strain distribution deviated from this assumption with the increased load due to the relative slips between the glulam beam and CLT flange. To calculate the bending performance of the composite floor, the M-shaped section of the glulam-CLT composite floor was simplified as T-section composite beams. The linear-elastic method for determining the flexural rigidity and ultimate bearing capacity of the glulam-CLT composite floors was proved to be accurate and reliable. The findings provided valuable insights into the bending behavior of the CLT flange under load and emphasized the non-uniform stress distribution caused by shear lag effects.

Mammary Schistosomiasis: Malignancy Mimicker or More?

Abstract Introduction/Objective Schistosomiasis is a neglected tropical disease (NTD) which affects more than 200 million people worldwide, with approximately 85% of cases occurring in sub-Saharan Africa. It serves both as an important etiologic agent in the development of carcinomas of many organ systems, as well as a common incidental histological finding in various organs, including the prostate, lung, spine, and liver. Detection of Schistosoma ova in the breast is rare. Here, we present a case of schistosomiasis of the breast in a patient concurrently diagnosed with breast carcinoma of the contralateral breast. Methods/Case Report A 48-year-old Mozambican female presented with a right breast mass, with suspicious microcalcifications detected in the contralateral breast on mammography. Biopsy confirmed invasive ductal carcinoma of no special type (NST) in the right breast and identified Schistosoma ova in the left, notably lacking an associated inflammatory response. A Ziehl-Neelsen special histochemical stain was negative, favoring schistosoma Hematobium species. Results (if a Case Study enter NA) NA Conclusion Our case marks the first in English literature where schistosomiasis was identified in the context of contralateral breast carcinoma, posing the question as to whether there is an association between schistosomiasis and breast carcinoma in our patient. One possible theory suggests hyperestrogenism secondary to Schistosoma infection in the liver. Breast schistosomiasis presenting as microcalcifications poses a diagnostic challenge, as it may clinically and radiologically resemble malignant breast disease. Histopathological diagnosis is crucial to confirm the diagnosis and prevent unnecessary procedures. Contrary to other organ systems, our case highlighted that schistosomiasis in the breast may not be accompanied by any inflammatory response. Definitive conclusions regarding the exact species of schistosomiasis cannot be drawn histologically based solely on H&E findings due to the plane of sectioning; therefore, performing a Ziehl-Neelsen stain is beneficial. As screening mammography increases in endemic areas, a high index of suspicion and further research is warranted.

Lateral performance of circular wooden columns reinforced with high-performance bamboo-based composite

This study researches the lateral performance of wooden columns strengthened with the non-damage reinforcement method, which used high-performance bamboo-based composite (HPBBC) materials and steel strips to form a hollow reinforcement system and then jacketed and reinforced the wooden columns. Six wooden columns strengthened by non-damage reinforcing methods were subjected to low cyclic loading tests under horizontal loads with a constant axial pressure ratio. The horizontal loads, displacements, and strain distributions of different locations at the column root were measured. The experimental results showed that the reinforcement method improved the lateral performance of wooden columns by about 4.96–58.54 %. Owing to the protective effect of the reinforcement system, the development of tensile damage to the wooden columns was delayed, but the breaking location was still the column root. In addition, the energy dissipation capacity and equivalent viscous damping coefficient of the reinforced wooden columns were significantly improved. The deformation of the strengthened column root conforms to the plane section assumption, while the deformation of the reinforcement system was lagged due to the absence of colloid and shear connectors between the wooden column and the reinforcement system. A bending capacity equation for the reinforced wood column was deduced based on the strain distribution in the damaged section. The error between the calculated and experimental results was within 13 %.

Experimental investigation of the compressive and shear resistance of laminated steel-reinforced glass beams

This paper presents an experimental investigation into the compressive and shear resistance of triple-layered laminated steel-reinforced glass beams. Two types of tests are performed: (a) local compressive tests (force over a support) and (b) bending tests (force close to a support). In total, six local compressive tests and eight bending tests are performed. Overall, beams with a shear span-to-effective depth ratio (a/d) approximately equal to 0, 0.63, and 1.0 are tested. Two different types of flexural reinforcement are used separately: solid (S) and hollow (H) reinforcement. The behaviour of the outer glass panes, and top and bottom reinforcement is monitored using strain gauges and Digital Image Correlation (DIC). The test results are elaborated in terms of load-displacement curves, the evolution of strains and crack patterns. Three failure modes are observed: yielding of the reinforcement (PF), crushing of glass (CF), and rupture of the reinforcement (RR). Shear failure occurred due to the crushing of glass in the compressed diagonal strut in the shear span. It was found that the shear resistance increases with a smaller shear span-to-effective depth ratio and stronger reinforcement. The dominant shear transfer mechanism was the direct strut action. It was found that the post-fracture capacity had a relatively constant value for all the tests with a slight increase for smaller a/d. The actual tensile strains in the bottom reinforcement measured by DIC are compared with the calculated strains based on the curvature of uncracked and cracked cross-sections, assuming plane section behaviour. It was observed that the actual strains are systematically larger than the calculated ones because, in reality, the section does not remain plane. After the appearance of the first crack, the beams essentially behave like strut-and-tie systems, where the strut is the diagonally compressed laminated glass and the tie is the bottom reinforcement.

Silicon photonic microresonator-based high-resolution line-by-line pulse shaping

Optical pulse shaping stands as a formidable technique in ultrafast optics, radio-frequency photonics, and quantum communications. While existing systems rely on bulk optics or integrated platforms with planar waveguide sections for spatial dispersion, they face limitations in achieving finer (few- or sub-GHz) spectrum control. These methods either demand considerable space or suffer from pronounced phase errors and optical losses when assembled to achieve fine resolution. Addressing these challenges, we present a foundry-fabricated six-channel silicon photonic shaper using microresonator filter banks with inline phase control and high spectral resolution. Leveraging existing comb-based spectroscopic techniques, we devise a system to mitigate thermal crosstalk and enable the versatile use of our on-chip shaper. Our results demonstrate the shaper’s ability to phase-compensate six comb lines at tunable channel spacings of 3, 4, and 5 GHz. Specifically, at a 3 GHz channel spacing, we showcase the generation of arbitrary waveforms in the time domain. This scalable design and control scheme holds promise in meeting future demands for high-precision spectral shaping capabilities.

In-silico heart model phantom to validate cardiac strain imaging

The quantification of cardiac strains as structural indices of cardiac function has a growing prevalence in clinical diagnosis. However, the highly heterogeneous four-dimensional (4D) cardiac motion challenges accurate “regional” strain quantification and leads to sizable differences in the estimated strains depending on the imaging modality and post-processing algorithm, limiting the translational potential of strains as incremental biomarkers of cardiac dysfunction. There remains a crucial need for a feasible benchmark that successfully replicates complex 4D cardiac kinematics to determine the reliability of strain calculation algorithms. In this study, we propose an in-silico heart phantom derived from finite element (FE) simulations to validate the quantification of 4D regional strains. First, as a proof-of-concept exercise, we created synthetic magnetic resonance (MR) images for a hollow thick-walled cylinder under pure torsion with an exact solution and demonstrated that “ground-truth” values can be recovered for the twist angle, which is also a key kinematic index in the heart. Next, we used mouse-specific FE simulations of cardiac kinematics to synthesize dynamic MR images by sampling various sectional planes of the left ventricle (LV). Strains were calculated using our recently developed non-rigid image registration (NRIR) framework in both problems. Moreover, we studied the effects of image quality on distorting regional strain calculations by conducting in-silico experiments for various LV configurations. Our studies offer a rigorous and feasible tool to standardize regional strain calculations to improve their clinical impact as incremental biomarkers.

Experimental and numerical investigation of bias performance of steel fiber-reinforced GRC-CFFT columns

Geopolymer concrete-filled glass fiber-reinforced polymer (GFRP) tube columns show significant potential in marine engineering due to their excellent durability and mechanical properties. This study investigated the bias performance of steel fiber-reinforced geopolymer recycled aggregate concrete-filled GFRP tube (SGRC-CFFT) columns, considering variables such as load eccentricity, GFRP tube thickness, fiber winding angle, and recycled coarse aggregate (RCA) replacement rate. The failure modes, load-displacement behaviors, and strain distribution were analyzed and discussed. Furthermore, a high-precision finite element model was established based on the test data. The test results indicated that increasing load eccentricity significantly reduced both the load-bearing and axial deformation capacity of CFFT columns. When the load eccentricity reached 0.40, the peak load of the specimen was only 39 % of that of the corresponding axial compression specimen. A higher RCA replacement rate would cause a more pronounced reduction in bias-bearing capacity, with a maximum decrease of 24.6 %. Before 80 % of the peak load, the axial deformation of the column mid-span section accorded to the plane section assumption. Due to the eccentric load, the hoop deformation of the CFFT column was concentrated on the compression side. The fiber winding angle was the critical factor influencing both the peak load and the peak moment of the biased SGRC-CFFT column.

Testicular mosaicism in non-mosaic postpubertal Klinefelter patients with focal spermatogenesis and in non-mosaic prepubertal Klinefelter boys.

Do testis-specific cells have a normal karyotype in non-mosaic postpubertal Klinefelter syndrome (KS) patients with focal spermatogenesis and in non-mosaic prepubertal KS boys? Spermatogonia have a 46, XY karyotype, and Sertoli cells surrounding these spermatogonia in postpubertal patients also have a 46, XY karyotype, whereas, in prepubertal KS boys, Sertoli cells surrounding the spermatogonia still have a 47, XXY karyotype. A significant proportion of patients with non-mosaic KS can have children by using assisted reproductive techniques thanks to focal spermatogenesis. However, the karyotype of the cells that are able to support focal spermatogenesis has not been revealed. Testicular biopsy samples from non-mosaic KS patients were included in the study. Karyotyping for sex chromosomes in testis-specific cells was performed by immunohistochemical analysis of inactive X (Xi) chromosome and/or fluorescent in situ hybridization (FISH) analysis of chromosomes 18, X, and Y. A total of 22 KS patients (17 postpubertal and 5 prepubertal) who were non-mosaic according to lymphocyte karyotype analysis, were included in the study. After tissue processing, paraffin embedding, and sectioning, the following primary antibodies were used for cell-specific analysis and Xi detection; one section was stained with MAGE A4 for spermatogonia, SOX9 for Sertoli cells, and H3K27me3 for Xi; the other one was stained with CYP17A1 for Leydig cells, ACTA2 for peritubular myoid cells, and H3K27me3 for Xi. Xi negative (Xi-) somatic cells (i.e. Sertoli cells, Leydig cells, and peritubular myoid cells) were evaluated as having the 46, XY karyotype; Xi positive (Xi+) somatic cells were evaluated as having the 47, XXY. FISH stain for chromosomes 18, X, and Y was performed on the same sections to investigate the karyotype of spermatogonia and to validate the immunohistochemistry results for somatic cells. According to our data, all spermatogonia in both postpubertal and prepubertal non-mosaic KS patients seem to have 46, XY karyotype. However, while the Sertoli cells surrounding spermatogonia in postpubertal samples also had a 46, XY karyotype, the Sertoli cells surrounding spermatogonia in prepubertal samples had a 47, XXY karyotype. In addition, while the Sertoli cells in some of the Sertoli cell-only tubules had 46, XY karyotype, the Sertoli cells in some of the other Sertoli cell-only tubules had 47, XXY karyotype in postpubertal samples. In contrast to the postpubertal samples, Sertoli cells in all tubules in the prepubertal samples had the 47, XXY karyotype. Our data also suggest that germ cells lose the extra X chromosome during embryonic, fetal, or neonatal life, while Sertoli cells lose it around puberty. Peritubular myoid cells and Leydig cells may also be mosaic in both postpubertal patients and prepubertal boys, but it requires further investigation. The number of prepubertal testicle samples containing spermatogonia is limited, so more samples are needed for a definitive conclusion. The fact that not all the cell nuclei coincide with the section plane limits the accurate detection of X chromosomes by immunohistochemistry and FISH in some cells. To overcome this limitation, X chromosome analysis could be performed by different techniques on intact cells isolated from fresh tissue. Additionally, there is no evidence that X chromosome inactivation reoccurs after activation of the Xi during germ cell migration during embryogenesis, limiting the prediction of X chromosome content in germ cells by H3K27me3. Our findings will lay the groundwork for new clinically important studies on exactly when and by which mechanism an extra X chromosome is lost in spermatogonia and Sertoli cells. This study was funded by The Scientific and Technological Research Council of Türkiye (TUBITAK) (2219 - International Postdoctoral Research Fellowship Program for Turkish Citizens) and the Strategic Research Program (SRP89) from the Vrije Universiteit Brussel. The authors declare no competing interests. N/A.

In-silico heart model phantom to validate cardiac strain imaging.

The quantification of cardiac strains as structural indices of cardiac function has a growing prevalence in clinical diagnosis. However, the highly heterogeneous four-dimensional (4D) cardiac motion challenges accurate "regional" strain quantification and leads to sizable differences in the estimated strains depending on the imaging modality and post-processing algorithm, limiting the translational potential of strains as incremental biomarkers of cardiac dysfunction. There remains a crucial need for a feasible benchmark that successfully replicates complex 4D cardiac kinematics to determine the reliability of strain calculation algorithms. In this study, we propose an in-silico heart phantom derived from finite element (FE) simulations to validate the quantification of 4D regional strains. First, as a proof-of-concept exercise, we created synthetic magnetic resonance (MR) images for a hollow thick-walled cylinder under pure torsion with an exact solution and demonstrated that "ground-truth" values can be recovered for the twist angle, which is also a key kinematic index in the heart. Next, we used mouse-specific FE simulations of cardiac kinematics to synthesize dynamic MR images by sampling various sectional planes of the left ventricle (LV). Strains were calculated using our recently developed non-rigid image registration (NRIR) framework in both problems. Moreover, we studied the effects of image quality on distorting regional strain calculations by conducting in-silico experiments for various LV configurations. Our studies offer a rigorous and feasible tool to standardize regional strain calculations to improve their clinical impact as incremental biomarkers.

Investigation of wake dynamics near the cylinder with the variation of length-to-diameter ratio

The study investigates the impact of drag forces on underwater pipeline structures at junctions where diameter changes occur, utilizing three-dimensional numerical simulations to analyze flow patterns around dual-step cylinders at a Reynolds number of 5000. The numerical model is validated against benchmark studies for a plain circular cylinder at heating condition, demonstrating strong agreement. Subsequently, cylinder temperatures were varied to assess their influence on drag force. The study further explores the effect of varying the aspect ratio L/D from 1 to 3 on drag reduction. Analysis of the flow structures is conducted, focusing on vortex patterns, velocity fields, and force coefficients surrounding the cylinders. Additionally, streamwise and crosswise velocities are analyzed at different sectional planes of the step cylinder. Results indicate that the drag force diminishes with increasing aspect ratio, correlating with formation length (Lf). At lower aspect ratios, step-induced vortices migrate toward the wall, while at higher aspect ratios, they drift midway. This research provides insights for designing stepped diameter cylinder systems in the subcritical regime, contributing to optimized underwater pipeline structures.

Analysis of spiral antenna for enhancing antenna-plasma coupling impedance for SST-1 tokamak

Abstract A detailed characterization of a high-power radio frequency (RF) broadband circularly polarized two-arm spiral antenna is designed to operate within the frequency range of 0.1–1.0 GHz. The impedance matching network technique is introduced to optimize its performance. The traditional spiral antenna is excited by a vertical or horizontal balun, whereas the proposed design is directly fed by a coaxial cable featuring a planar feeding section specially optimized to achieve broadband input impedance matching. The spiral antenna is designed as per the steady-state superconducting tokamak (SST-1) port space constraints. The simulated efficiency of the RF power coupling with the hydrogen plasma is ∼70 %. Through simulation, it was evident that the proposed antenna exhibited inherent resonance at 0.5 GHz with a reflection coefficient of −27.94 dB and an axial ratio is 3.39 dB respectively. The obtained outcomes unequivocally demonstrate the circular polarization of the designed antenna. Overall, the findings support the enhancement of plasma heating and current drive techniques in fusion research.

An analytical model of longitudinal joints in the segmental lining of shield tunnels with considering geometric nonlinearity

The previous mechanical analysis on the longitudinal joint of segmental linings commonly used the plane section assumption, in which the strains on the normal section are linearly and continuously distributed. This was proven to be overidealized according to a series of full-scale tests in existing literatures. In this paper, the nonlinear characteristics of deformation behavior for longitudinal joint were investigated with emphasis on the geometric nonlinearity of joint. A new analytical model of longitudinal joint was proposed with considering the geometric nonlinearity via employing the local plane section assumption to describe the strain distribution of joint section. The effectiveness of the proposed model was validated and parametric study (e.g. loading cycles and peak bending moment) was conducted. The results indicated the geometric nonlinearity of longitudinal joint refers to the increase area of free surface for the joint section. This nonlinearity will cause the discontinuous change of contact state which can be intuitively charactered by the height of concrete compression zone. Without considering the geometric nonlinearity, the area of concrete compression zone and bending capacity of the joint are overestimated by 45% to 100% based on the calculation result of the verification case. The increasing load cycles and peak load value deteriorate the deformation recoverability and ultimate capacity of joints. The degree of geometric nonlinearity is intensified with the increase of load cycles and peak load value but it can be alleviated if the concrete in external edge contact during overloading process.

Nuclei and Tracts in the Telencephalon of Crocodiles: Identification and Characterization Using an Organizational Scheme Applicable to Other Reptiles.

The telencephalon of reptiles has been suggested to be the key to understanding the evolution of the forebrain. Nevertheless, a meaningful framework to organize the telencephalon in any reptile has, with rare exception, yet to be presented. To address this gap in knowledge, the telencephalon was investigated in two species of crocodiles. A variety of morphological stains were used to examine tissue in transverse, horizontal, and sagittal planes of sections. Besides providing a description of individual nuclei, brain parts were organized based on two features. One was related to two fixed, internal structures: the lateral ventricle and the dorsal medullary lamina. The other was the alignment of neurons into either layers, cortex, or not, nucleus. Viewed from this perspective, all structures, with limited exceptions, could be accurately placed within the telencephalon regardless of the plane of section. Furthermore, this framework can be applied to other reptiles. A further extension of this scheme suggests that all structures in the telencephalon could be grouped into one of two categories: pallial or basal.

Cone beam computed tomography and cross-sectional anatomy of the region of the fetlock in the horse (Equus caballus).

This study aimed to delineate the detailed anatomy of the metacarpophalangeal (MCP) and metatarsophalangeal (MTP) joints in healthy horses using cone beam computed tomography (CBCT). The fetlock region of 15 cadaveric forelimbs and 14 cadaveric hindlimbs from nine adult horses without orthopaedic disease underwent CBCT scanning. Additionally, arthrography CBCT scans were conducted following intra-articular injection of a radiopaque contrast medium containing blue epoxy resin dye. Subsequently, limbs were frozen and sectioned to visualize anatomical structures in sectional planes corresponding to selected CBCT images. CBCT proved suitable for detailed visualization of the bony components of the fetlock region. Furthermore, the common digital extensor tendon, superficial and deep digital flexor tendons, suspensory ligament, and straight and oblique sesamoidean ligaments were identifiable on CBCT images. However, certain ligaments, such as the collateral sesamoidean ligaments and intersesamoidean ligaments, were not clearly identified. The hyaline cartilage of the MCP and MTP joint facets was assessable on the post-contrast sequence. In cases where a radiographic or ultrasound examination cannot provide a definitive diagnosis and determine the extent of disease, CBCT can provide additional valuable data on the equine MCP and MTP joint. The images obtained in this study can serve as a reference for CBCT examination of the equine MCP and MTP joint.