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In image processing, computer vision algorithms are applied to regions bounded by closed contours. These contours are often irregular, poorly defined, and contain holes or unavailable areas inside. A common problem in computational geometry includes finding the k-sided polygon (k-gon) of maximum area or maximum perimeter inscribed within a contour. This paper presents a generic method to obtain user-defined polygons within a region. Users can specify the number k of sides of the polygon to obtain. Additionally, users can also decide whether the calculated polygon should be the largest in area or perimeter. This algorithm produces a polygon or set of polygons that can be used to segment an image, allowing only relevant areas to be processed. In a real-world application, the validity and versatility of the proposed method are demonstrated. In addition, the source code developed in Java and Python is available in a GitHub repository so that researchers can use it freely. [ABSTRACT FROM AUTHOR]

In contrast to the conventional etching that makes nanoparticles rounder and our previous sharpening etching mode that causes serrated edges, here, we developed a new boring etching mode that targets the faces of Au nanoplates to make holes. The critical factors are the pre-incubation step with the ligand 2-mercapto-5-benzimidazolecarboxylic acid (MBIA) and the subsequent removal of excess ligands in the solution. Thus, etching is focused onto the few sites with initial loss of ligands, which cannot be quickly replaced. The choice of ligand MBIA is also of importance, as it carries negative charge and repels each other. Its inability of forming a dense layer probably plays a critical role in the site-selectivity for faces, because ligands at the higher curvature edges and corners are expected to have less repulsion. The etching results from the comproportionation reaction between Au3+ and Au0 in the nanoplates, where Br− coordination to Au and the extra stabilization from cetyltrimethylammonium bromide (CTAB) are essential. We believe that the ability of boring holes is an important tool for future synthetic designs. [ABSTRACT FROM AUTHOR]

Experiments are conducted to investigate the effect of a drainage layer in/below saturated tailings on leakage through a hole of various shapes and sizes in a 2-mm-thick HDPE geomembrane. Three cases: no drainage (Case 1), drainage layer between two layers of tailings (Case 2), and drainage layer below tailings and above the GMB (Case 3) are examined. Analytical solutions predicting leakage through a circular GMB hole overlain by tailings with an internal drainage in (Case 2) and below (Case 3) tailings are developed, and match the experimental and numerical results well. Results show that a drainage layer separated from the GMB by a thin layer of tailings (Case 2) gives leakage slightly greater than if no drainage layer is present, but 3-5 orders of magnitude lower than when the drainage is placed directly over the GMB (Case 3). In Case 3, leakage is dependent on the hydraulic conductivity k of both the drainage and subgrade, and is not affected by the tailings. Unlike Cases 1 and 2 where the subgrade has negligible effect on leakage, a low permeability subgrade with k less than 10% of k for the drainage layer is recommended in Case 3 to minimize leakage through geomembrane defects. • first investigation of the effect of an internal drainage within tailings on leakage through a GMB defect. • first evaluation of where to place the internal drainage in order to minimize leakage through a GMB defect. • first guidance on how to predict leakage through a GMB defect when a drainage is placed at different positions. [ABSTRACT FROM AUTHOR]

We have obtained straight-line-shaped agglomeration grooves of 2~3.5 μm width in the ~60-nm-thick Si thin films by the continuous-wave laser crystallization (CLC) when the laser power is increased above the optimum power to obtain grain boundary-free (GB-free) films. The GB-free CLC is suitable for fabricating monolithic three-dimensional integrations. The grooves are formed in the Si film vertically from the Si surface to the underlying insulating substrate, and a hump of the Si film is generated along the edge of the groove at the retarded side of the scan. In situ observation of the crystal growth shows that the grooves originate from voids, which happen to be generated by agglomeration in the melt zone. The voids move at a constant velocity, Vvoid , within the melt zone. The melt zone moves at the scan velocity, V, to the scan direction. The void velocity, Vvoid , is obtained from the angle of the groove line to the scan direction, and is found to be proportional to V−0.5. [ABSTRACT FROM AUTHOR]

Electrical discharge drilling of blind holes has been a challenging task due to the inherent difficulties in removing debris from the discharging gap. This paper investigates the working mechanism and effects of new stepped electrodes which are used in conjunction with injection flushing in drilling deep blind holes. A series of theoretical simulations and comparative experiments were conducted using cylindrical electrodes and two types of stepped electrodes. Pulse waveforms were captured to analyse the discharge status. Surface topography and machining quality were analysed using scanning electron microscope (SEM) images. The machining performance was evaluated by studying the material removal rate (MRR) and tool wear ratio (TWR). Experiment results show that internal flushing caused the debris to circulate in the machining zone and led to abnormal discharges, disrupting the formation of the plasma channel. The MRR was increased by 75% and 82% when using cylindrical electrodes with pressures of 120 psi and 40 psi, respectively. In contrast, the MRR with injection flushing was about 80% of that without injection flushing when using stepped electrodes. Regardless of the type of electrode, the application of injection flushing resulted in the increase in the maximum effective machining depth. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Current studies on blasting construction of small clear-distance tunnels have not considered the impact of existing tunnel lining defects when establishing safety controls. This paper offers a series of study results based on the blasting project of a new tunnel adjacent to the existing defect Xinling tunnel to thoroughly examine the dynamic response, safety control standards, and measures of the existing defect tunnel. First, structural models were developed to investigate the influence of the presence or absence of specific defects (like lining cracks and cavities behind the lining) on the dynamic response of the current tunnel lining to identify the most unfavorable defect distribution. Then, establish safety control standards for intact linings and those with the most unfavorable defects. Eventually, two types of control measures, single safe charge and reasonable delay time, were studied based on the established safety control standards. In particular, the most adverse position of cracks was the wall facing the explosion, the rise in depth was more unfavorable for vibration response, and the impact of the longitudinal crack was restricted to the vicinity of the crack. While the vault was the most adverse cavity position, the rise in cavity area was more damaging, and the influence range varied with longitudinal cavity length. Moreover, the impact of cracks was mainly evident in the amplification effect of stress at the crack region. In contrast, cavities had varied degrees of ampli- fication effects on the vibration velocity and stress response and a relatively extensive influence range. Safety control research was conducted, when the tunnel was intact, with a right wall crack, a vault cavity, and both vault cavity and crack for this project, the peak particle velocity (PPV) of the safety control standard for vibration velocity was 13, 10, 13, and 8 cm/s, respectively, and the respective single safe charge could be adjusted at 64, 53, 37, and 25 kg. However, the presence of different defects had a relatively negligible effect on the reasonable delay time; 25 ms was recommended for existing tunnel lining with and without the defect. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Almaty Technological University is the property of Almaty Technological University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The design of three-dimensional printing based conformal cooling channels (CCCs) in injection molding holds great significance. Compared to CCCs, conformal cooling (CC) cavity solutions show promise in delivering enhanced cooling performance for plastic products, although they have been underexplored. In this research, CC cavity is designed within the mold geometry, reinforced by body-centered cubic (BCC) lattice structures to enhance mechanical strength. Three distinct BCC lattice variations have been integrated into the CC cavity: the BCC structure, BCC with cubes, and BCC with pillars. The thermal performances of the BCC lattice-added CC cavity are assessed numerically after experimental validation. To provide feasible solutions from viewpoints of thermal performances, various BCC lattice structure thicknesses are analyzed in the range of 0.8–1.2 mm. Thermal simulation outcomes reveal that thicker lattice structures enhance mechanical strength but simultaneously lead to an increase in cooling time. Upon examining all the proposed CC cavity solutions supported by BCC, the cooling times range from 2.2 to 4 s, resulting in a reduction of 38.6% to 66.1% when compared to conventional straight-drilled channels. In contrast to CCCs, CC cavities have the potential to decrease the maximum temperature non-uniformity from 8.5 to 6 K. Nevertheless, the presence of lattice structures in CC cavity solutions results in an elevated pressure drop, reaching 2.8 MPa, whereas the results for CCCs remain below 2.1 MPa. Graphic Abstract [ABSTRACT FROM AUTHOR]

This contribution takes the form of a transcript of a prayer/interview. A prayer is a speech act directed into a void, towards an absence (a hole, so to speak). It 'lays claim to an immediate connection with the Being whose absence fills the world' as Anne Carson writes in reference to the mystics Simone Weil and Marguerite Porete (2005: 177). The aspiration of a prayer, not unlike a spell or curse, is to directly affect something or someone in the real and physical world through an act of speech (Carson 2005: 177). The following text is developed in reference to the three existing books of the writings and teachings of the mystic St. Catherine of Siena. Parts of the text are fictionalized, reassembled and borrow direct and attributed quotes of these books. The script features characters called K, an amalgam of the researcher and the persons, figures and subjects I converse with in my research. K blurs the authorial voice by mingling it with others, in an attempt to flatten the authority of the narrating voice towards polyvocality. Combining the forms of prayer, interview, dialogue, written conversation and play serves to explore and apply different registers of writing that correspond with St. Catherine's chosen forms of communication and to (playfully with a nod to common academic methodologies) investigate the holeyness/brokenness of dialogical speaking voices, the wounded text and a textual approach towards the unsayable/unthinkable. [ABSTRACT FROM AUTHOR]

SnO2/BiOBr photocatalytic materials were successfully synthesized by hydrothermal method with BiOBr as the precursor. X‐ray diffraction studies confirmed that BiOBr and SnO2 were successfully combined. After characterization, we proposed a possible formation mechanism for SnO2/BiOBr. The degradation experiment showed that the degradation rate of norfloxacin using SnO2/BiOB‐4 reached 85.9 %, which was approximately 50 and 65 percentage points higher than that of pure BiOBr and SnO2, respectively. The reaction rate was 4.3 times that of BiOBr. Based on the analysis of the degradation mechanism, the improved photocatalytic performance may be attributed to the optimized energy band structure resulting from the combination of the two monomers. This promotes the effective separation of photogenerated electrons and holes, leading to the generation of more active substances such as ⋅O2− and h+. As a result, the oxidation capacity is enhanced. [ABSTRACT FROM AUTHOR]

Our critical analysis of Hutchinson's work, expressed in our recent article in the Annalen der Physik, which goes beyond mutual misunderstandings and misrepresentations, is also maintained in light of his Comment. The main reason for the limited yield in structural description is the author's adherence to the BGK method and the associated lack of a nonlinear dispersion relation (NDR). Even with an additional asymptotic constraint, as a supposed replacement for the NDR, the author's theory remains inferior to the pseudo‐potential method. [ABSTRACT FROM AUTHOR]

The efficient cobalt doping of zinc oxide nanoparticles grown by chemical method, with Co2+ substituting the Zn2+ cations, is proved by electron spin resonance spectroscopy for cobalt concentration from 0.01% to 1.00%. The gradual killing of the usual core‐defect signal (g ≈ 1.96) as the Co concentration is increased prevents its ionization by optical excitation from X0 to X−, thus inhibiting the corresponding hole releasing. Consequently, the •CH3 methyl radical is no longer generated on the nanoparticles surface by the photo‐Kolbe reaction h++CH3COO−→•CH3+CO2. It is thus confirmed that the hole involved in the dissociation of surface acetate actually comes from the optically excited core‐defect g = 1.96, and that the number of these defects can be tuned by some very small amount of cobalt impurities. [ABSTRACT FROM AUTHOR]

Hydraulic fracturing is a mainstream technology for unconventional oil and gas reservoirs development all over the world. How to use this technology to achieve high-level oil and gas resource extraction and how to form complex fracture networks as hydrocarbon transportation channels in tight reservoirs, which depends to a large extent on the interaction between hydraulic and pre-existing cracks. For hydraulic fracturing of fractured reservoirs, the impact of natural fractures, perforation direction, stress disturbances, faults and other influencing factors will produce a mixed I&II mode hydraulic fracture. To forecast whether hydraulic fractures cross pre-existing fractures, according to elastic mechanics and fracture mechanics, a stress state of cracks under the combination of tensile (I) and shear (II) is presented. A simple mixed-mode I&II hydraulic fracture's crossing judgment criterion is established, and the propagation of hydraulic fractures after encountering natural fractures is analyzed. The results show that for a given approaching angle there exists a certain range of stress ratio when crossing occurs. Under high approaching angle and large stress ratio, it is likely that hydraulic cracks will go directly through pre-existing cracks. The reinitiated angle is always controlled within the range of approximately 30°C among the main direction of penetration. [ABSTRACT FROM AUTHOR]

This article explores the links between creative imagination and extraction in the Democratic Republic of the Congo (DRC). This question has an undeniable memorial dimension, for extraction, as a crucial point of entry into Congolese historical consciousness, allows for a multi-perspectivist examination of the way in which the memory of the past has been archived, experienced, and (mis) interpreted. As a key term to understand Congo's geopolitical position since colonial times, extraction offers a rich array of tropes and ideas to assess culture from the DRC and the Congolese diaspora. First, I reflect on the notions of extraction and extractivism; secondly, I analyse how they form the basis of Sammy Baloji's multimedia work in Mémoire (2006) and Mémoire/Kolwezi (2014); then, I turn to La Danse du vilain (2020) and Tram 83 (2014) by Fiston Mwanza Mujila, first to assess how extraction is employed in these novels, then to conduct a reflection on 'necropolitics', and reveal little-known aspects of diamond digging during the Mobutu era. I will also show that Baloji's and Mujila's creative trajectories have been enriched by dialogues with Filip De Boeck, the Belgian social anthropologist and specialist of the DRC. [ABSTRACT FROM AUTHOR]

The primary focus of this paper is to investigate the application of ANSYS Workbench 19.2 software's advanced feature, known as Separating Morphing and Adaptive Remeshing Technology (SMART), in simulating the growth of cracks within structures that incorporate holes. Holes are strategically utilized as crack arrestors in engineering structures to prevent catastrophic failures. This technique redistributes stress concentrations and alters crack propagation paths, enhancing structural integrity and preventing crack propagation. This paper explores the concept of using holes as crack arrestors, highlighting their significance in increasing structural resilience and mitigating the risks associated with crack propagation. The crack growth path is estimated by applying the maximum circumferential stress criterion, while the calculation of the associated stress intensity factors is performed by applying the interaction integral technique. To analyze the impact of holes on the crack growth path and evaluate their effectiveness as crack arrestors, additional specimens with identical external dimensions but without any internal holes were tested. This comparison was conducted to provide a basis for assessing the role of holes in altering crack propagation behavior and their potential as effective crack arrestors. The results of this study demonstrated that the presence of a hole had a significant influence on the crack growth behavior. The crack was observed to be attracted towards the hole, leading to a deviation in its trajectory either towards the hole or deflecting around it. Conversely, in the absence of a hole, the crack propagated without any alteration in its path. To validate these findings, the computed crack growth paths and associated stress intensity factors were compared with experimental and numerical data available in the open literature. The remarkable consistency between the computational study results for crack growth path, stress intensity factors, and von Mises stress distribution, and the corresponding experimental and numerical data, is a testament to the accuracy and reliability of the computational simulations. [ABSTRACT FROM AUTHOR]

In a classic paper of 1960, W. H. Cherry and J. I. Gittleman discussed various thermal and electrodynamic aspects of the superconductive transition process relevant to practical applications. In a section of the paper that has remained unnoticed, they proposed a physical model for the Meissner effect. Earlier in 1940–1943, in work that has also remained unnoticed, K. M. Koch had introduced related physical ideas to explain the Meissner effect. Still earlier in 1937, J. C. Slater proposed a model to explain the perfect diamagnetism of superconductors. None of these ideas are part of the conventional London-BCS understanding of superconductivity, yet I will argue that they are essential to understand the Meissner effect, the most fundamental property of superconductors. The unconventional theory of hole superconductivity unifies and extends these ideas. A key missing element in the conventional theory as well as in these early theories is electron-hole asymmetry. A proper understanding of the Meissner effect may help with practical applications of superconductors, as well as to find new superconducting materials with desirable properties. [ABSTRACT FROM AUTHOR]

The excavation of adjacent pits following the initial foundation pit excavation can significantly influence ground settlement. Using a foundation pit excavation project in Changzhou as a prototype, this study employed the numerical simulation method in conjunction with the HSS model to analyze the settlement deformation characteristics of the original excavation and compare them with the recorded monitoring values. In this study, the analysis focused on the ground settlement between two pits by varying the spacing between them at different excavation depths. The findings revealed that the ground settlement does not exhibit a significant increase when the new pit is excavated at a shallow depth. However, it rapidly increases when the excavation depth of the new pit surpasses that of the existing pit. Furthermore, an increase in the distance between the two pits causes the maximum settlement position to shift towards the edge of the new pit. The maximum ground settlement is found to have a linear relationship with both the maximum horizontal displacement of the two pits and the spacing between them. [ABSTRACT FROM AUTHOR]

Photoelectrochemical water splitting is a promising approach to produce green and renewable hydrogen fuel, alleviating the CO2 emissions, air pollution, and energy crisis. However, the efficiency is limited by the recombination of photogenerated carriers and the losses of holes, resulting in a mismatch between the rates of water oxidation and reduction reactions. This article starts with a discussion of the principle of photoelectrochemical water splitting, highlighting the role and importance of holes, and then summarizes the development of the hole transport layer, with a focus on the classification of the hole transport layer, the structure and properties of common hole transport materials, and the construction and improvement of the hole transport layer. Finally, it is concluded with a summary and perspective of strategies for the future development of the hole transport layer. [ABSTRACT FROM AUTHOR]

Copyright of German International Journal of Modern Science / Deutsche Internationale Zeitschrift für Zeitgenössische Wissenschaft is the property of Artmedia24 and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on the band structure of TlGaTe compound, the extrema of the valence and conduction bands were determined and the tensor of the components of the inverse effective mass of electrons and holes was calculated. [ABSTRACT FROM AUTHOR]

Introduction: Colonoscopy is the most frequently used procedure in the early diagnosis and treatment of many colon diseases, especially colon malignancies. With the increase in the use of colonoscopy, an increase in the number of colonoscopy-related perforations has been observed. This study aimed to determine the frequency of perforation and the management of colonoscopic perforation. Materials and Methods: Patients who underwent colonoscopy between January 2012 and December 2022 and were determined to have iatrogenic colon perforation were included in the study. The dermographic characteristics of the patients, length of hospital stay, comorbidity status (defined using the guidelines of the American Society of Anesthesiologists), colonoscopy indications, diagnostic tool of perforation, treatment and follow-up methods were examined and collected. Results: 16,385 patients were examined in the study cohort. Perforation was detected in a total of 12 (0.07%) patients, 8 women and 4 men. The average age of perforated patients was 62 (23-87) years. Eleven patients were treated with surgical intervention and 1 patient was treated with the endoscopic clip method. One patient died on the 20th day after surgery. Conclusion: Although colonoscopic examination is important for the diagnosis and treatment of colon and rectal diseases, the possibility of procedure-related perforation should not be ignored. Early diagnosis enables minimal surgical procedures such as laparoscopic repair and endoscopic clip application. Immediate surgical management, preferably primary repair and sometimes resection, appears to be a good strategy for most patients. [ABSTRACT FROM AUTHOR]

This study aims to assess the effect of notches and holes on the structural performance of laminated veneer lumber (LVL) joists using experimental and numerical methods. A total of 40 samples were manufactured with three different notch depths and without notch and tested under a three-point bending load. Subsequently, detailed numerical models were developed and validated with experimental results. The effect of a notch, hole, and location on the load-carrying capacity, shear and flexural stress, and flexural stiffness of the LVL joist were evaluated through the validated numerical model. Results showed that the hole and notch significantly affect the structural performance of the LVL joist. Further, the notch or hole in the middle of the bending span induces a higher load-carrying capacity reduction (i.e., more than 50%) than that of from shear span. Further, the larger hole (i.e., size beyond 33% of the joist' depth) located in the shear and bending span reduced the load-carrying capacity by more than 15% and 50%, respectively. A similar reduction was also observed in the flexural and shear stress of the LVL joist. Moreover, this study proposed a response surface-based model to predict the failure load and flexural stiffness of LVL joists with and without holes and notches. [ABSTRACT FROM AUTHOR]

Surface deformation analysis plays a crucial role in understanding geodetic phenomena and their implications for hazard assessment, infrastructure management, and environmental studies. In recent years, the incorporation of synthetic aperture radar (InSAR) and advanced processing techniques have been used to monitor surface deformation. One such technique, LiCSBAS, has shown great promise in analyzing InSAR time series data to accurately detect and quantify surface displacements. It has been successfully employed in various geodetic monitoring scenarios such as landslide monitoring, infrastructure stability assessment, and volcanic deformation analysis. In this study, studies were reviewed in which performance evaluation and comparison of LiCSBAS with other technologies were discussed as well as future developments and challenges in this field. The results of a review of previous studies show the effectiveness of LiCSBAS in detecting and analyzing surface deformation, allowing for a better understanding of geodetic processes. This overview will provide a set of ideas that will assist stakeholders involved in surface deformation analysis and geodetic monitoring and contribute to decision-making to achieve sustainable development. [ABSTRACT FROM AUTHOR]

We solve the problem of steady-state transverse vibration of an orthotropic plate of any shape containing a set of reinforced holes of arbitrary configuration under the action of a harmonic (in time) load arbitrarily distributed over the surface. We use the equations of the refined theory of plates that take into account the transverse shear strains and all inertial components. The solution is constructed by using the indirect boundary-element method. Numerical results are presented for the case where the contours of the holes and the outer boundary of the plate have superelliptic shapes. [ABSTRACT FROM AUTHOR]

We report on the discharge of the capacitance formed at the electrodes in flash experiments with yttria stabilized zirconia. The experiments were carried out by disconnecting the current, and, instead, short circuiting the electrodes through a resistor. The time dependent voltage across the resistor was measured; the ratio yielded the discharge current. The current decayed exponentially with time, as expected in an RC circuit, which allowed the measurement of the capacitance. Experiments were carried out in two ways. In one case the specimens were flashed within a glove box filled with Ar (< 1 ppm O2): these yielded electronic conductors. In the other case the specimens were flashed in ambient air: while electronically conducting in‐flash these specimens recover their prior insulating behavior as soon as the current is turned off. The stored charge was two orders of magnitude greater in the Ar experiments. Rather unexpectedly, the sign of the voltage expressed at the electrodes was opposite in experiments carried out in air and in Ar. The capacitance measured in the discharge experiments is attributed to the formation of space charge adjacent to the electrodes. In the case of Ar experiments, the capacitance is very large, approaching 1 F; in this case the space charge is expected to be constituted from ions. In the air experiments the specimen becomes insulating, trapping the electrons as a space charge. Hall effect measurements of the carrier density and X‐ray photoelectron spectroscopy characterization of electronically conducting single crystal specimen of cubic zirconia are reported. [ABSTRACT FROM AUTHOR]

Low-frequency electrical noise is a sensitive measure of defects in semiconductor devices because the noise has an impact, directly or indirectly, on the performance and reliability of the device. Its measurement is particularly important to characterize noise in semiconductor devices. [ABSTRACT FROM AUTHOR]

Along with the well-known metal artefacts produced in series specific to the Bronze Age, unique, prestige products were also manufactured in the Carpathian area. Among them the Larga type axes stand out both by their very small number and by their beauty. Summing up specific elements, found individually and in the case of other axes (semi-calotte flat, curved blade, decoration on the sleeve and so on), the use of the term hybrid axes is justified. Their similarity with Drajna-type axes is obvious, supporting their symbolic value. The last known axe, discovered in Mihalţ, in a gravel pit, is also the only Transylvanian piece, the rest of the discoveries being known from Maramureş and Ukraine. Their dating is relative, with no specific context, but they can be dated in the Late Bronze and associated / contemporary with Wietenberg, Gligoreşti or Komarow manifestations. [ABSTRACT FROM AUTHOR]

The steppe marmot (Marmota bobak Mull.) is an important component of the Eurasian forest steppes. However, at the turn of the XIX-XX centuries. The steppe marmot was almost exterminated in Russia. In the Privolzhskaya Forest-Steppe Nature Reserve, as a result of reintroduction, marmots live on the territory of the Ostrovtsovskaya Forest-Steppe. In 2023, in the spring-summer period, using a UAV (DJI MavicAir 2s), we took photographs and interpreted orthophotomaps using the ArcMap 10.4 program. Maps of the location of various types of marmot holes, trails and butanes were created. Vegetation research has been carried out since 2019. At the base of different types of burrows, the floristic composition was identified. On the territory of the Ostrovtsovskaya forest-steppe reserve area, over the past 10 years (since marmots settled this territory), 210 burrows were noted in the surveyed marmot colonies. Three types of burrows have been identified – temporary burrows are divided into protective and permanent summer ones, as well as wintering ones. 78 species of vascular plants were identified in the marmot colonies. The grass species most resistant to failure are Festuca valesiaca, Calamagrostis epigeios and Bromopsis inermis. The total area of territory used by marmots has increased 4 times over 7 years. The degree and nature of the impacts of marmot colonies on vegetation depend on the time and intensity of burrow use, as well as the stability of the plant communities themselves. In the habitats of marmots, herbaceous polycarpics are the absolute dominants; on butanes, the participation of annual and biennials plants.

ABSTRACT The infection cycle of phage λ terminates in lysis mediated by three types of lysis proteins, each disrupting a layer in the bacterial envelope: the S105 holin, the R endolysin, and the Rz/Rz1 spanin complex targeting the inner membrane, cell wall or peptidoglycan, and the outer membrane, respectively. Video microscopy has shown that in most infections, lysis occurs as a sudden, explosive event at a cell pole, such that the initial product is a less refractile ghost that retains rod-shaped morphology. Here, we investigate the molecular basis of polar lysis using time-lapse fluorescence microscopy. The results indicate that the holin determines the morphology of lysis by suddenly forming two-dimensional rafts at the poles about 100 s prior to lysis. Given the physiological and biochemical similarities between the lambda holin and other class I holins, dynamic redistribution and sudden concentration may be common features of holins, probably reflecting the fitness advantage of all-or-nothing lysis regulation.IMPORTANCEIn this study, we use fluorescent video microscopy to track -green fluorescent protein (GFP)-labeled holin in the minutes prior to phage lysis. Our work contextualizes prior genetic and biochemical data, showing when hole formation starts and where holin oligomers form in relation to the site of lytic rupture. Furthermore, prior work showed that the morphology of lambda-infected cells is characterized by an explosive event starting at the cell pole; however, the basis for this was not clear. This study shows that holin most often oligomerizes at cell poles and that the site of the oligomerization is spatially correlated with the site of lytic blowout. Therefore, the holin is the key contributor to polar lysis morphology for phage lambda.

Perforations after endoscopic retrograde colangiopancreatography (ERCP) are divided into four types. Type 1 refers to the duodenum, type 2 the periampullary region, type 3 the bile duct itself, and type 4 the observation of retroperitoneal free air on cross-sectional imaging. The treatment of type 2 biliary perforations remains debatable. We present a patient who was successfully treated with a self-expandable metal stent (SEMS) without the need for surgery or any complications. [ABSTRACT FROM AUTHOR]

The aim of this chapter is to highlight some conceptual connections between the concept of zero and the philosophical concept of śūnyatā. Both ideas first arose in the Indian subcontinent, and I will try to suggest that this geographical congruence is more than a coincidence. As such, this will likely be a more speculative contribution to this volume than others, but I will attempt to substantiate my proposal by stressing the conceptual advantages deriving from such a syncretic enterprise. I will begin with an overview of the historical development of the number and concept of zero, followed by some considerations of its treatment in contemporary mathematics, as well as an examination of its less-evident semiotic properties. I will then proceed to re-examine the concept of śūnyatā, identifying its central meontological significance in the philosophy of Nāgārjuna. In this context, I will examine the idea of the 'trace' in the thought of Jacques Derrida, viewing it as another actor in the assemblage of concepts that I attempt in this chapter. Finally, I undertake a synthetic reading of these three 'voids' -- of zero, of śūnyatā, and of the trace -- aimed at a speculative rearrangement of these heterogeneous concepts, in a philosophical exercise that I see as both a possible and a necessary evolution of 'comparative philosophy'. [ABSTRACT FROM AUTHOR]

The study examines the effectiveness of two rows of hybrid film cooling holes over a plate surface using infrared technology and a thermal wind tunnel. The two rows consist of seventeen coolant injection holes, with nine in the first row and eight in the second row. Two cases were studied: case 1 using cylindrical holes and case 2 using hybrid holes. Both cases had the same cross-sectional area with a hydraulic diameter of 5.3 mm and a forward coolant injection angle of 30° in the streamwise direction. Different blowing ratios (mass flows ratio between the coolant and mainstream) were tested at 0.5, 1.0, and 1.5. The study focuses on evaluating the impact of hole shape with various blowing ratios on film cooling effectiveness. In addition, thermal images of the test surface were taken via an infrared camera after reaching a steady state. The results indicated that at a blowing ratio of 0.5, there was a significant enhancement in film efficacy, with a decrease in the test surface temperature of the cylinder and hybrid hole cases by 31.8% and 35.0%, respectively, when compared to a blowing ratio of 1.0 and 1.5, which had a temperature increase. Therefore, the film cooling effectiveness decreased to 30.9% and 32.4%, and 29.5% and 31.7% for the cylinder and hybrid hole cases, respectively. Additionally, the better overall film cooling effectiveness in this study was achieved by the configuration of the hybrid holes at a blowing ratio of 0.5, which resulted in a film cooling effectiveness of 35.0%. [ABSTRACT FROM AUTHOR]

We construct regularized Sherman-type integral equations for the anisotropic plane problem of the theory of elasticity. An integral representation of the general solution is obtained for a plane with holes in terms of the complex Lekhnitskii potentials with the help of the Cauchy theorem and, for a half plane, with additional application of the Green solutions. The properties of the constructed integral equations are investigated and their eigensolutions are found. On the basis of the Sherman approach, we introduce regularizing components, which enable us to find single-valued solution by numerical methods. By using the developed approach, we determine the elastic stresses formed near mine workings in rock massifs with anisotropic mechanical characteristics in the presence of gravitational forces. We perform the investigation of stresses near cylindrical cavities with circular and oval cross sections in isotropic materials and in aleurolite rock masses. The mutual influence of the cavities on the distribution of stresses is analyzed. [ABSTRACT FROM AUTHOR]

The process of laser formation of microholes in semiconductor substrates using an EM-4452-1 laser-processing unit with a pulse repetition frequency of a picosecond laser from 10 to 300 kHz at a radiation energy up to 10 μJ is investigated. The combination of high-speed movements of the laser beam by the galvanoscanner system and precise positioning of the processed material increases the efficiency of laser microprocessing and expands the functional capabilities of the equipment. [ABSTRACT FROM AUTHOR]

Chronic Non-Specific Low Back Pain (cNSLBP) has been identified as one of the leading global causes of disability and is characterized by symptoms without clear patho-anatomical origin. The majority of clinical trials assess cNSLBP using scales or questionnaires, reporting an influence of cognitive, emotional and behavioral factors. However, few studies have explored the effect of chronic pain in daily life tasks such as walking and avoiding obstacles, which involves perceptual-motor processes to interact with the environment. Are action strategies in a horizontal aperture crossing paradigm affected by cNSLBP and which factors influence these decisions ? 15 asymptomatic adults (AA) and 15 cNSLBP participants walked along a 14 m long path, crossing through apertures ranging from 0.9 to 1.8 times their shoulder width. Their movement was measured using the Qualisys system, and pain perception was evaluated by self-administered questionnaires. The cNSLBP participants stopped rotating their shoulders for a smaller aperture relative to their shoulder width (1.18) than the AA participants (1.33). In addition, these participants walked slower, which gave them more time to make the movement adaptations necessary to cross the aperture. No correlation was found between the variables related to pain perception and the critical point but the levels of pain were low with a small variability. This study shows that during a horizontal aperture crossing task requiring shoulder rotation to pass through small apertures, cNSLBP participants appear to exhibit a riskier adaptive strategy than AA participants by minimizing rotations that could induce pain. This task thus makes it possible to discriminate between cNSLBP participants and pain-free participants without measuring the level of pain. The identification number registered in the clinical trials is NCT05337995. • Investigation of cNSLBP movement strategies in an ecological context. • Horizontal aperture crossing paradigm discriminated the influence of cNSLBP. • cNSLBP participants stopped turning their shoulder at a smaller opening. • Pain perception scores were not correlated with the critical point but were low. [ABSTRACT FROM AUTHOR]

Shear tests on rectangular plate sandstone containing two pre-existing holes were performed to analyze the shear mechanical responses and cracking evolution mechanisms. With generation of the penetrating fracture surfaces, both shear stress and normal displacement show a dramatic drop. Then, during the shear slipping process, the shear stress increases once again due to wear and shear off of the surface asperities, and three different variation trends of the normal deformation including shear dilation, fluctuation, and shear contraction are respectively identified. The role of ligament length and normal stress on several key indices such as peak shear stress, peak normal displacement and residual shear stress was investigated. Violent AE (acoustic emission) responses occur along with penetration of the fracture surfaces, and in the shear slipping process, AE events continue to occur due to wear of surface asperities, while the increase rate of accumulative AE events declines. Cracks coalesced at the rock bridge and running through the rock matrix form the main failure planes of the samples. From the PFC2D simulation results, the crack clusters first initiate from hole-walls and coalesce at the rock bridge for a small ligament length, while first produce the main failure planes at the right/left rock matrix for a large ligament length. The total number of micro cracks shows a “calm → rapid increase → decreasing growth amplitude” variation during shearing, and the induced cracks become more concentrated for a larger normal stress, implying a cumulative damage of the failure surfaces.

Introduction. The main problem of the behaviour of composite structures is the method of combining materials that have different qualitative characteristics. In the case of collaboration of concrete and steel, the load-bearing capacity of the structure increases, while the consumption of materials decreases. Thanks to these advantages, the use of steel-reinforced concrete floor slabs is more and more popular. A theoretical study has made it possible to assess the load-bearing capacity of a floor slab.Materials and methods. A theoretical analysis of the bearing capacity of a composite floor slab is proposed. Four samples, that consisted of a galvanized steel plate embedded in a concrete parallelepiped, were used to conduct experimental studies. Rectangular plates had different types of surface: smooth, perforated with holes, with stamped “pins”, and with bolted connecting elements.Results. The analysis of the bearing capacity of a steel-reinforced concrete floor slab, that has bent profiles, was performed. The deformation dependences of the experimental samples were obtained; the graphs describing the dependence of displacement on the load for the four types of surfaces are made; the values of the load at which samples fail, and the dependence of the breaking load on the structure of the embedded part of the plate are identified.Conclusions. The analysis of the bearing capacity of a steel-reinforced concrete floor slab, that has bent steel sections, has shown that the use of light steel thin-walled beams is possible if spans correspond to residential and public buildings. The results of the experiment allow to conclude that the collaboration of concrete and a steel beam is possible without any additional elements in the composite structures that have bent sections. Adhesive properties of materials and the stamped part of the section can take the shear forces arising in structures.

The article deals with the issues of improving the productivity and quality of drilling holes. The results of systematization and introduced into production methods of drilling with changing cutting modes during insertion and entry of the drill, grinding of descending chips and removal of it and the cutting zone are developed, tool materials, coolant compositions are promising, cutting modes are optimal, a mathematical model of the influence of modes and methods of drilling on hole accuracy and quality. An algorithm of the proposed drilling methods for machine tools with program control has been compiled.

In a classic paper of 1960, W. H. Cherry and J. I. Gittleman discussed various thermal and electrodynamic aspects of the superconductive transition process relevant to practical applications. In a section of the paper that has remained unnoticed, they proposed a physical model for the Meissner effect. Earlier in 1940–1943, in work that has also remained unnoticed, K. M. Koch had introduced related physical ideas to explain the Meissner effect. Still earlier in 1937, J. C. Slater proposed a model to explain the perfect diamagnetism of superconductors. None of these ideas are part of the conventional London-BCS understanding of superconductivity, yet I will argue that they are essential to understand the Meissner effect, the most fundamental property of superconductors. The unconventional theory of hole superconductivity unifies and extends these ideas. A key missing element in the conventional theory as well as in these early theories is electron-hole asymmetry. A proper understanding of the Meissner effect may help with practical applications of superconductors, as well as to find new superconducting materials with desirable properties.

The primary focus of this paper is to investigate the application of ANSYS Workbench 19.2 software’s advanced feature, known as Separating Morphing and Adaptive Remeshing Technology (SMART), in simulating the growth of cracks within structures that incorporate holes. Holes are strategically utilized as crack arrestors in engineering structures to prevent catastrophic failures. This technique redistributes stress concentrations and alters crack propagation paths, enhancing structural integrity and preventing crack propagation. This paper explores the concept of using holes as crack arrestors, highlighting their significance in increasing structural resilience and mitigating the risks associated with crack propagation. The crack growth path is estimated by applying the maximum circumferential stress criterion, while the calculation of the associated stress intensity factors is performed by applying the interaction integral technique. To analyze the impact of holes on the crack growth path and evaluate their effectiveness as crack arrestors, additional specimens with identical external dimensions but without any internal holes were tested. This comparison was conducted to provide a basis for assessing the role of holes in altering crack propagation behavior and their potential as effective crack arrestors. The results of this study demonstrated that the presence of a hole had a significant influence on the crack growth behavior. The crack was observed to be attracted towards the hole, leading to a deviation in its trajectory either towards the hole or deflecting around it. Conversely, in the absence of a hole, the crack propagated without any alteration in its path. To validate these findings, the computed crack growth paths and associated stress intensity factors were compared with experimental and numerical data available in the open literature. The remarkable consistency between the computational study results for crack growth path, stress intensity factors, and von Mises stress distribution, and the corresponding experimental and numerical data, is a testament to the accuracy and reliability of the computational simulations.