Regular Units Research Articles

Mechanisms of Sarcomere Assembly in Muscle Cells Inferred from Sequential Ordering of Myofibril Components

Voluntary movement in animals is driven by the contraction of myofibrils in striated muscle cells, which are linear chains of regular cytoskeletal units termed sarcomeres. While the ordered structure of mature sarcomeres, key to muscle contraction, is well established, the physical mechanism governing sarcomere assembly is still under debate. Here we put forward a theory of sarcomere self-assembly based on data. We measured the sequential ordering of sarcomere components in developing flight muscles, using a novel tracking-free algorithm. We find that myosin molecular motors, α-actinin cross-linkers, and the titin homologue Sallimus form periodic patterns before actin filaments become polarity sorted. Based on these, we propose that myosin, Sallimus, and sarcomere Z-disk proteins including α-actinin dynamically bind and unbind to an unordered bundle of actin to establish an initial periodic pattern. Periodicity of actin filaments is established only later. Our model proposes that nonlocal interactions between spatially extended myosin and titin/Sallimus containing complexes, and possibly tension-dependent feedback mediated by an α-actinin catch bond, drive this ordering process. We probe this hypothesis using mathematical models and derive predictive conditions for sarcomere pattern formation to guide future experiments. Published by the American Physical Society 2024

Reducing temperature rise in metal meshes exposed to incident electromagnetic waves through regular polygonal unit structure

Reducing temperature rise in metal meshes exposed to incident electromagnetic waves through regular polygonal unit structure

Molecular dynamics study on effect of wettability on boiling heat transfer of thin liquid films

How surface wettability affects boiling heat transfer of thin liquid film on a nanoscale remains a challenging research topic. In this work, the effects of wettability on the nanoscale boiling heat transfer for a thin liquid film on hydrophilic surface and hydrophobic surface are investigated by molecular dynamics simulation. Results demonstrate that the hydrophilic surface has better heat transfer performance than the hydrophobic surface. It has a shorter boiling onset time, higher temperature, heat flux, interfacial thermal conductance, and weakened interfacial thermal resistance. The hydrophilic surface throughout has higher critical heat flux than the hydrophobic surface in both macro-system and nanoscale system. Besides, a two-dimensional surface potential energy is proposed to reveal the mechanism of wettability affecting the boiling heat transfer. The absolute value of potential energy in one regular unit of hydrophilicity (–0.34 eV) is much higher than that of hydrophobicity (–0.09 eV). That is the crucial reason why the heat transfer enhancement via improving surface wettability should be primarily the powerful surface potential energy. In addition, the interaction energy is calculated to further address the nucleation mechanism and heat transfer performance for liquid film on different wettability surfaces. The interaction energy values are ordered as <i>I</i><sub>phi</sub> (1.57 eV/nm<sup>2</sup>) > <i>I</i><sub>water</sub> (0.48 eV/nm<sup>2</sup>) > <i>I</i><sub>pho</sub> (0.26 eV/nm<sup>2</sup>), indicating that the better heat transfer performance of hydrophilic surface is because of the large interaction energy at the solid/liquid interface. Besides, the bubble nucleation on a hydrophilic surface needs absorbing more energy and occurs inside the thin liquid film, while it needs absorbing less energy and triggering off at the solid/liquid interface with hydrophobicity. Those uncover the principal mechanisms of how wettability influences the bubble nucleation and boiling heat transfer performance on a nanoscale.

Viscoplastic micromechanical response of three-dimensional, two-phase unit cell composites with particles at regular positions

A Fast Fourier Transform (FFT)-based viscoplasticity simulation is performed to study the microstructure-property relationship of the unit cell metal-metal composites. Three-dimensional digital unit cell composites, composed of single-crystalline hard BCC particles at “regular” positions and a single-crystalline soft FCC matrix, are used as instantiations to calculate the stress and strain-rate fields under uniaxial tension. Such “regular” unit cell composites are generated by growing particles from either simple cubic, body centered cubic or face centered cubic grid points, having particle volume fractions from 0.1 to 0.9. Topologically, each type of regular unit cell is found to be unique. Moreover, its topological measures change drastically once particles initiate simultaneous contacts. While the macroscopic mechanical behavior as a function of the particle volume fraction is insensitive to the type of the unit cell, the local micromechanical response of each phase shows a strong dependence both on the morphological evolution as a function of the particle volume fraction as well as on the type of the unit cell. However, such morphological effects on the local mechanical response weaken when the matrix has a hard crystallographic orientation with respect to the tension direction. No single determining microstructural feature could by itself explain the complex variation in the micromechanical response of the unit cell composite.

Турмархия Готия и византийский топотерит на Мангупе в конце X начале XI века

Introduction. The article examines the circumstances of the simultaneous appearance at the end of the 10th century in the central fortress of the Mountain Crimea – Doros, a byzantine garrison led by topotherete and the establishment of a separate tourmarchia of Gothia in the region. A special study of the issue allows to expand understanding of the causes and content of military-administrative reform. Methods. The research is interdisciplinary in nature. It takes into account all available information from written, sphragistic, epigraphic and archaeological sources about the events that took place in Taurica during the reign of emperor Vasily II (976–1025). Analysis. Establishment at the end of the 10th century in the Mountain Crimea the tourmarchia of Gothia and the appearance of Byzantine topotherete in Doros are events that had common causes. In the case of the tourmarchia we are talking about a plan to create an independent administrative structure in the mountainous part of the peninsula, which was supposed to quickly respond to external threats and over time be transformed into a “small” theme typical of its epoque. The residence of the tourmarch was the Mangup fortress, where no later than 994–995 the reconstruction of the fortifications was completed. These works were supervised by a byzantine official with the title topotherete, who stood at the head of a regular military unit and whose powers were reminiscent of those known from the second half of the 8th century topotheretes of cities in the border provinces of the empire. Results. The history of the tourmarchia in Mountain Crimea was short and ended around the middle of the 11th century. However, its appearance and existence were fully consistent with the military-administrative practice of Byzantium at that time in many regions of the empire, where numerous “small” thematic structures were created in dangerous areas to contain the expansion of the enemy or consolidate the empire in the conquered territories.

More than Meets the Eye: A Qualitative Investigation of the Complex Weight History Constructions of Brazilian Women Who Underwent Bariatric Surgery

Most studies on bariatric surgery identify personal factors such as “non-compliance” to lifestyle changes as the cause of weight gain and subsequent inability to lose weight. Prior qualitative studies suggest that weight loss patients have complicated relationships with both self and weight, with significant emotional and psychological implications. But how do patients themselves understand the trajectories of their weight gain as related to intrinsic versus extrinsic factors? A qualitative analysis examined the aspects involved in the construction of higher body weight from the perspectives and life experiences of Brazilian women who underwent bariatric surgery, considering that Brazil has previously been reported as a highly anti-fat society. Individual, semi-structured interviews were conducted with thirty women (15 aged 33-59 and 15 aged 63-72). Data were analyzed identifying the regular, expressive, and meaningful significance units identified through the interviews. Although it was expected that different life events were reported as crucial to the perceived aetiology of individual weight gain stories, the participants reported that the emotional aspects had more impact. The extremely high value attached to having a particular body weight negatively influenced the participants’ concept of identity and harmed their interactions and understanding of what it meant to be fully loved and accepted. Most of the participants underscored the importance of food in women’s lived experiences and explanations of weight gain. Despite this somatic response being dysfunctionally directed to food, this mechanism seemed to be vital to keeping them alive and engaged in the world. Finally, the participants faced layered vulnerabilities, which decreased their opportunities to access resources aimed at better body weight management. Broad approaches that consider emotional and physical care strategies must be proposed to this population.

Implementation of the Richmond Agitation-Sedation Scale (palliative version) on an inpatient palliative care unit

BackgroundThe Richmond Agitation-Sedation Scale – Palliative version (RASS-PAL) tool is a brief observational tool to quantify a patient’s level of agitation or sedation. The objective of this study was to implement the RASS-PAL tool on an inpatient palliative care unit and evaluate the implementation process.MethodsQuality improvement implementation project using a short online RASS-PAL self-learning module and point-of-care tool. Participants were staff working on a 31-bed inpatient palliative care unit who completed the RASS-PAL self-learning module and online evaluation survey.ResultsThe self-learning module was completed by 49/50 (98%) of regular palliative care unit staff (nurses, physicians, allied health, and other palliative care unit staff). The completion rate of the self-learning module by both regular and casual palliative care unit staff was 63/77 (82%). The follow-up online evaluation survey was completed by 23/50 (46%) of respondents who regularly worked on the palliative care unit. Respondents agreed (14/26; 54%) or strongly agreed (10/26; 38%) that the self-learning module was implemented successfully, with 100% agreement that it was effective for their educational needs.ConclusionUsing an online self-learning module is an effective method to engage and educate interprofessional staff on the RASS-PAL tool as part of an implementation strategy.

The Influence of Structuralism on the Formation of Contemporary Ukrainian Plastic Art

The article examines the influence of structuralism on the formation of plastic art in Ukraine in the second half of the 20th and early 21st centuries. First of all, we are talking about the creativity of the artists working in the field of fine and decorative arts and using wood as a material. It was outlined the defining principles of structuralism based on the works of contemporary researchers. Various structuralist approaches in cultural studies, philosophy and art are considered. For a deeper understanding of the nature of the Ukrainian plastic art the prerequisites for the development of structuralism in the visual arts on the basis of C. Monet's creative revolution and P. Cézanne's deep structural study of nature through geometry have been determined. The importance of P. Mondrian's creative experiments and the concept of neoplasticism introduced by him has been emphasized. The structuralist manifestos of C. Biederman, E. Bornstein and E. Wilmott have been analyzed. The creative method of structural reliefs of the Canadian artist of Ukrainian origin R. Kostyniuk, his inspirations and his own concepts of constructed compositions based on geometric shapes have been studied. In contrast to regular mechanical units and new technical material, the structural sculptures of E. Zelenak revealed the use of biomorphic forms built on the basis of repeating modules. D. Samil's constructed canvases of folded bright planes are mentioned. The article demonstrates the importance of the phenomenon of nonconformism in the Ukrainian artistic environment. Certain peculiarities of the application of theoretical developments in the figurative and plastic author's models of contemporary Ukrainian artists have been highlighted. A number of artistic interpretations and stylistic features in the formation of plastic art in Ukraine in the second half of the 20th and early 21st centuries have been revealed. The works of Ukrainian and diaspora artists who worked and continue to work in the second half of the 20th and early 21st centuries in Ukraine and abroad, namely R. Kostyniuk, E. Zelenak, D. Samyla, S. Savchenko, I. Stefiuk, V. Andrushko, Y. Titenkov, N. Symotiuk, D. Shavala, A. Savchuk, and I. Solovyov, have been considered. The research objective is to identify and investigate the influence of structuralism on the formation of contemporary Ukrainian plastic art, as well as to analyze the works of artists who used the structural method in their works. Research methodology. The methods of observation, comparison, analogy, experiment, formal analysis and synthesis have been used. Relevance and scientific novelty. In Ukrainian art history, the concept of "structuralism" in three-dimensional structures, sculpture, and plastic art remains poorly understood and requires a deeper study of the connections between the artist's intentions, materials, as well as the historical and cultural context in which the artwork has been created. The research of the influence of structuralism on contemporary Ukrainian sculpture and other forms of plastic art, which are formed on such basic principles of the structural method as code, sign, structure, symbol, and color, reveals a new critical approach to the interpretation of creative experiments as an identifier of a completely new artistic paradigm.

The Use of Alternative Rooms in Forensic and Regular Psychiatric Units: A Scoping Review.

(1) Background: Emotional regulation, distress and relational conflicts often occur during hospitalization and rehabilitation on psychiatric units, especially in patients suffering from severe and persistent mental disorders. While widely used in children and geriatric patients, little literature exists on the use and outcomes of alternative rooms in the context of forensic and regular psychiatric units for adult patients. Considering the scarcity of the literature on alternative use, this study is motivated by the following research question: what are the main uses and outcomes of alternative rooms in the context of forensic and regular psychiatric units? The main objective of this study is to conduct a scoping review of the use and outcomes of alternative rooms for the context of psychiatric inpatients. (2) Methods: A systematic search was performed in the electronic databases of MedLine, Web of Science, PsycNet (PsycINFO) and Google Scholar from their inception dates until 2022. (3) Results: A total of nine studies were analyzed. Sensory, multisensory rooms, Snoezelen, and comfort rooms are the types of alternative rooms discussed in these studies. Distress and anxiety reduction, increase in self-esteem, impact on seclusion rates, patient-staff communication and alliances, heart and respiration rate reduction, and improvement of alexithymia were identified among the main uses and outcomes of these rooms. (4) Conclusions: The scarcity of literature available to draw information from for this review and possible impact on improving patient outcomes and quality of treatment in psychiatric units opens the door to future studies to better understand the efficacy of such rooms. Research into the ideal implementation tactics of such rooms, long-term outcomes, and the influence on diverse patient demographics could be areas of improvement in the use of alternative rooms.

Defect sensitivity mitigation in the compressive mechanical response of two-phase lattice metamaterials

Engineered materials commonly referred to as metamaterials are materials that offer appealing features such as customisable stiffness and strength, auxetic behaviour and energy absorption. This work focuses on the classical 2D lattice metamaterial configuration with regular triangular unit cell. A combination of two dissimilar materials is employed in the design process: the primary material that constitutes the lattice structure is composed of thermoplastic polyurethane (TPU), while an incompressible silicone serves as the secondary material, completely filling selected lattice cells. In order to investigate the mechanical response of such lattices to intrinsic defects, geometric imperfections are intentionally introduced. Three distinct types of geometric anomalies, i.e. curvature of some elements, lateral shift of some lattice nodes, and reduced beam thickness, are randomly introduced. Additively manufactured perfect and defective lattices are subjected to compressive loading for both empty and silicone filled cases. Overall, the results reveal that the lattices show a significant improvement with the assumed reinforcing filling pattern, helping to prevent the buckling of the beams under compression and enhancing the load bearing capacity of the structure at higher deformations. Finite element (FE) analyses are performed to validate the experimental results, demonstrating how the filling pattern enhances the mechanical response of the lattices.

Assessment of Risk Variables in the Post-Anesthesia Care Unit of a Tertiary Care Hospital in Dhaka

Background: In a location apart from the regular intensive care unit (ICU), the postanaesthetic care unit (PACU) provides postoperative high-dependency or intense care for high-risk surgical patients. Therefore, it meets the population's well-documented need for better postoperative care. Objectives: The aim of the study was to Assess the risk variables in the post-anesthesia care unit of a tertiary care hospital in Dhaka. Methods: This cross-sectional descriptive study was carried out in the Department of anesthesiology, Uttara Adhunik Medical College Hospital, during October 2020 to September 2021. A total of 100 patients were participate in this study. Patients underwent tonsillectomy, hysterectomy, caesarean section, and laparoscopic cholecystectomy, both male and female were included in this study. Patients who have not given consent to participate in the study were excluded from the study. Statistical Packages for Social Sciences (SPSS-26), where required. Results: About 40% patients were male and 60% were female. 80% of the patients were under ASA classification-1, 15% under ASA classification-2 and 5% were under ASA classification ≥3. Here, 22.22% patients had pre-exixting co-morbidity of respiratory, CVS neurological disease respectively. 30% had DM. Only 3.33% and more than 1 pre-exixting co-morbidity. 94.20% patients had no risk of surgery and only 5.80% patients were under risk of surgery. About 40% patients stayed 60-120 minutes in the post anesthesia care unit, 30% patients stayed 120-180 minutes in the post anesthesia care unit, 20% patients stayed 180-240 minutes in the post anesthesia care unit and 10% patients stayed ≥240 minutes in the post anesthesia care unit. 5% patients had develop complication in the post anesthesia care unit for 1-2 hours, 32% for 2-3 hours, 20% for 3-4 hours and 25% for more than 4 hours. Conclusion: The main reasons for a prolonged stay in the post-anesthesia care unit are perioperative cardiovascular and respiratory ....

Impact of concrete masonry unit geometry on masonry assemblage strength

An experimental investigation of 126 masonry prisms was conducted to assess the influence of concrete masonry unit web height on structural response. All prisms had the same overall geometry, were either grouted or left hollow, and included regular stretcher units with full-height webs, knock-out units with remaining web height conforming to typical Canadian practice, or knock-out units with remaining web height resulting in a calculated normalized web area approaching the minimum permissible in accordance with U.S. standard ASTM C90. Cracks in hollow prisms shifted from the centre of the exterior web face for those constructed with regular stretcher units to the web–face shell interface as the remaining web height decreased. The stability of the grout columns in grouted prisms reduced stress concentrations at the web–face shell interface and the effects of increased restraint with reduced height-to-thickness ratio.

Jordan Regular Units in Rings and Group Rings

Jordan Regular Units in Rings and Group Rings

Бойові резерви Державної прикордонної служби України в бойових діях на Донбасі (весна – літо 2014 р.)

The study aim to analysis of the historical experience of the participation of com- bat reserves of the State Border Guard Service of Ukraine in the hostilities in the Ukrainian Donbas in the spring and summer of 2014. Research methodology is based on the principles of historicism, objectivity, comprehensive analysis, and the modern conceptual and categori- cal apparatus used by military history in describing the process of armed struggle. Th e histori- cal and systematic method, as well as the methods of analysis and synthesis, are used. The scientifi c novelty lies in an attempt to systematically study the history of the participation of the combat reserves of the Border Guard Service in the hostilities conducted by the Ukrainian Defense Forces in the Luhansk and Donetsk regions in the spring and summer of 2014 during the counteraction to Russian aggression. Conclusions. The combat reserves of the State Border Guard Service were formed as freelance units with the main goal of strengthening the border guard units that guarded the Ukrainian-Russian state border in the eastern regions of Ukraine. Their service and combat activities in the spring and summer of 2014 can be divided into two stages, each of which diff ered in the socio-political situation and the intensity of hostilities. As the hostilities clearly demonstrated, due to the lack of regular missile and artillery weapons and the necessary amount of armored vehicles, the border guards’ combat reserves were able to fi ght only sabotage and reconnaissance groups and some illegal armed groups of local pro-Russian collabo- rators. As for confronting the regular units of the Russian armed forces by conducting full-scale combat operations against them, the border guards were predictably unprepared.

플렉서블디자인효과 조율을 위한 3D유닛패턴 디자인방법 체계화

The purpose of this study was to provide a systematic design method that can harmonize the images of order and change, which can be considered as the visual characteristics of the Flexible Design Pattern(FDP). The research reviewed previous studies by grouping them according to their types and presented a design template that can harmonize visual impressions. As a result, the designmethod of FDP is summarized in threeways, startingwith the square division based onmodular and Fibonacci grid, creating order and change through the presence of symmetry manipulation in the shape design and development process, drawing visual effects while maintaining the convenience of a single unit by dividing the square into isomorphism and dimorphism, and creating unexpected intermediate forms through the overlap of large and small units. The design method that can harmonize the visual impressions of these patterns revolves around design aspects and development methods. In other words, design factors include division methods, shape design, cell combinations(cell overlap), and unit composition, while development methods include regular and irregular unit development using symmetry, among other factors that influence visual effects. The variations in impressions generated by these factors were symbolically indicated, and ultimately, a design template consisting of four adjustment directions and four combination methods was provided to facilitate the expression of the images of order and change. Furthermore, this study not only establishes a theoretical foundation for productization but also provides practical tools for design,which is expected to be useful not only for further research but also for design education.

플렉서블디자인효과 조율을 위한 3D유닛패턴 디자인방법 체계화

The purpose of this study was to provide a systematic design method that can harmonize the images of order and change, which can be considered as the visual characteristics of the Flexible Design Pattern(FDP). The research reviewed previous studies by grouping them according to their types and presented a design template that can harmonize visual impressions. As a result, the designmethod of FDP is summarized in threeways, startingwith the square division based onmodular and Fibonacci grid, creating order and change through the presence of symmetry manipulation in the shape design and development process, drawing visual effects while maintaining the convenience of a single unit by dividing the square into isomorphism and dimorphism, and creating unexpected intermediate forms through the overlap of large and small units. The design method that can harmonize the visual impressions of these patterns revolves around design aspects and development methods. In other words, design factors include division methods, shape design, cell combinations(cell overlap), and unit composition, while development methods include regular and irregular unit development using symmetry, among other factors that influence visual effects. The variations in impressions generated by these factors were symbolically indicated, and ultimately, a design template consisting of four adjustment directions and four combination methods was provided to facilitate the expression of the images of order and change. Furthermore, this study not only establishes a theoretical foundation for productization but also provides practical tools for design,which is expected to be useful not only for further research but also for design education.

Comparison of different numerical modelling approaches for the assessment of the out-of-plane behaviour of two-leaf stone masonry walls

This work compares the ability of different numerical modelling approaches to simulate the out-of-plane behaviour of two-leaf stone masonry walls with different masonry bond configurations: an irregular drystone stone masonry wall and a masonry wall with roughly cut regular stone units. Finite element modelling, considering both a micro and macro-modelling approach, and the distinct element method have been compared in this study, which intends to (i) provide an insight regarding parameter estimation and the calibration procedure for each modelling approach considered; (ii) highlight their pros and cons of the selected modelling strategies; (iii) further expand the existing literature addressing the numerical modelling of two-leaf stone masonry walls.

Topology optimization design of graded infills for 3D curved volume by a conformal sweeping method

Swept volumes are widely existed in various significant engineering applications. However, an effective design method for the lightweight swept volume with porous infills is lacking. This paper develops a novel topology optimization method for the design of curved volumes filled with spatially-varying microstructures. The infill optimization formulation for the curved swept volume is established to concurrently optimize both the microstructural geometry and the macroscopic distribution of the graded infills, aiming at minimizing the structural compliance subject to a global volume constraint. A conformal sweeping approach is developed to map the curved volume into a regular parameterization​ cube along the sweeping trajectory. In this fashion, the graded infills defined in a regular unit cell can be first filled into this cubic parameterization space, and then reversely mapped into the original volume to conformally match the curved geometry. A numerical homogenization method for parallelepiped microstructures is introduced to evaluate several sampling microstructures. The local level sets approach is used to create a family of connectable microstructures, while a polynomial interpolation is employed to rapidly interpolate the graded property of the generated microstructures based on the properties of sampling microstructures. Two different sweeping volume types are investigated. Several examples with respect to the infill optimization design of curved swept volumes are provided to illustrate the characteristics of the proposed method.

Jordan regular units in rings and group rings

UDC 512.5 The concept of Lie regular elements and Lie regular units was defined and studied by Kanwar, Sharma and Yadav in <em>Lie regular generators of general linear groups</em>, Comm. Algebra, <strong>40</strong>, № 4, 1304–1315 (2012)]. We introduce Jordan regular elements and Jordan regular units. It is proved that the order of the set of Jordan regular units in M ( 2 , Z 2 n ) is equal to a half of the order of U ( M ( 2 , Z 2 n ) ) . Further, we show that the group ring K G of a group G over a field K of characteristic 2 has no Jordan regular units.

Folded Digital Meta-Lenses for on-Chip Spectrometer.

In-plane diffractive optical networks based on meta-surfaces are promising for on-chip application. The design constraints of regular antenna unit place ultimate limits on the functionalities of the meta-systems. This fundamental limitation has been reflected by the large footprints of cascaded meta-surfaces. Here, we propose a digital meta-lens with a large degree of design freedom, enabling significantly improved beam focusing, collimation, and deflection capabilities. A highly dispersive and compact diffractive optical system is constructed for spectrometer via five layers of meta-lenses in a folded configuration. The device only occupies a 100 μm × 100 μm chip area on a silicon photonic platform. Sparse and continuous spectra reconstruction is achieved over a 35 nm bandwidth. Fine spectral lines separated by 0.14 nm are resolved. In addition to such a compact and high-resolution on-chip spectrometer, it is also expected to be promising for imaging, optical computing, and other applications due to the great versatility of the digital lens design.