Related Structures Research Articles

Green water loads on prismatic obstacles

Green water loads on prismatic obstacles (representing topside structures) mounted on the raised deck of a simplified vessel are investigated using computational fluid dynamics simulations and physical model testing with emphasis on examining different structure shapes, orientation angles and relative structure size. For each scenario investigated, several flow features are identified that characterize the green water interaction with the structure and influence loads, namely delayed flow diversion, formation of a vertical jet, scattered wave formation and the development of complex wake patterns. Comparing across structures, these interactions are more pronounced for blunt objects, and the associated force impulse is larger. For example, a cube with flow at normal incidence is found to experience approximately twice the force impulse of a circular cylinder of the same projected area. Equally, rotation of the cube leads to reduced run-up height and streamwise force on the structure. To explain these trends, a theoretical model based on Newtonian flow theory is adopted. This model provides an estimate of the streamwise force exerted on obstacles in high-Froude-number flows and shows good agreement with the numerical results when the flow is supercritical, shallow (small water depth relative to structure width) and the structure is tall (large structure height relative to water depth). Despite some limitations, the model should provide an efficient force prediction tool for practical use in design.

Thiophene-fused aromatic belts

Aromatic belts, ultrashort carbon nanotubes, and related structures, are emerging molecular entities in the fields of organic electronics and supramolecular chemistry owing to their structural rigidity, fully fused π-conjugation, and well-defined cavity. Synthesis of aromatic belts with embedded thiophene structures, which manifest significant optoelectronic and conductive properties, has not yet been achieved. Herein, we report the synthesis of thiophene-fused aromatic belts (thiophene belts) via one-step sulfur cross-linking reaction of partially fluorinated cycloparaphenylenes. Their structural features, including unidirectional columnar stacking with high dipole moment in crystals, two-dimensional layer assembly on metal surfaces, and photophysical properties, such as long-lifetime phosphorescence, are uncovered. These distinctive features of the thiophene belts should inspire a range of applications such as optoelectronic devices and polar materials.

Three generations of infinite-layer nickelate crystals

Abstract Topotactic transformations between related crystal structures represent a powerful method for synthesizing novel quantum materials. In particular, the groundbreaking discovery of superconductivity in nickelates with the infinite-layer (IL) crystal structure—achieved through the topotactic oxygen reduction of the perovskite phase—has sparked recent interest in topotactic methods. However, while most topotactic reductions of nickelates were performed on polycrystalline powders or thin films, single-crystalline samples, which are the gold standard for physical property measurements in quantum materials, remain underexplored. Here, we summarize our progress in synthesizing IL nickelate bulk crystals. We review both breakthroughs and limitations encountered, and also discuss critical insights into the microstructural effects of the topotactic transformation of bulk crystals provided by scanning transmission electron microscopy. Graphical abstract

Generational variations in wellbeing: suicide rates, cohort characteristics, and national socio-political context over seven decades

Abstract Over recent decades, the relative wellbeing of younger birth cohorts declined in many western countries, indicating growing generational inequality. Building on Durkheimian theory, this paper examines explanations for these changes, hypothesizing that differences in cohort wellbeing are related to variations in social integration associated with birth cohorts and national socio-political contexts. Age–period-specific suicide rates of men and women from 1950 to 2020 in 19 highly developed western nations, including 26 birth cohorts, born from 1875 to 2004, are examined using estimable function analysis and age–period–cohort characteristic (APCC) models. Cohort variations in wellbeing are significantly greater in English-speaking nations, which have traditionally provided less institutionalized support and social integration than continental European nations. Age-specific suicide rates are larger for cohorts with childhood demographic characteristics associated with less social integration (relative cohort size and family structure). Major historical events associated with social integration in formative years of late adolescence and young adulthood also influence cohort wellbeing, with higher age-specific rates for cohorts experiencing the Great Depression of the 1930s and health pandemics of the early 20th and 21st centuries and lower rates for those experiencing periods of war and national conflict. However, the magnitude of these associations is strongly influenced by socio-political context. Negative effects of cohort characteristics are muted and positive effects are enhanced in the continental nations. In addition, patterns of associations vary by age and gender. Results remain with strong controls for the pace of change, additional measures of national context, and sensitivity analyses.

Effects of motor imagery and action observation on pelvic floor and related structures in healthy women: A randomized controlled trial

The main aim was to assess the effects of motor imagery (MI) and action observation (AO) plus physical exercise (PE) on pelvic floor and related structures. Forty-four healthy women were randomized into three groups: MI, AO, or sham observation (SO) group. The outcome measures included the pelvic floor muscles (PFM) condition (including basal tone and strength), lumbo-pelvic motor control, and pain sensitivity. All women performed six sessions at the rate of 3 s/week (for 2 weeks). An initial assessment was carried out (T0), another one 1-week after starting the study (T1), and a third one at the end (T2). Results showed significant PFM strength gains in MI and AO groups, but not in the SO group. Regarding lumbo-pelvic motor control, both MI and AO groups obtained statistically significant changes between pre- and post-intervention Additionally, only the AO group showed significant improvements already at 1-week of intervention. Finally, all groups showed improved pain sensitivity in the likely area of referred menstrual pain post-intervention, with only the MI group showing changes 1 week after starting the intervention. In conclusion, results showed that adding MI and AO to PE program leads to an improvement of sensorimotor function of PFM and related structures in general. Despite finding no statistically significant inter-group differences, some findings such as strength gains or the lumbo-pelvic motor control improvements were only found in MI and AO groups, and this should be considered clinically.

Multi-objective optimization of comprehensive performance in airfoil channel PCHEs using Bézier curves

The airfoil fin (AFF) Printed circuit heat exchanger (PCHE) has attracted significant attention for its excellent comprehensive performance. This study proposes an optimized design for AFF PCHE to enhance the comprehensive performance by integrating Bézier curves, computational fluid dynamics (CFD), and multi-objective genetic algorithm (MOGA). A set of 12 Bézier curve-based variables is utilized to define and control the airfoil geometry, with optimization targets set on two comprehensive evaluation criteria: the first enhanced ratio (η1) and the third enhanced ratio (η3). The MOGA-generated Pareto front reveals the evolution of AFF structures in relation to η1 and η3. Results show that as the leading and trailing edges of the AFFs become sharper and the thickness decreases, the η1 of the PCHE channel gradually increases, while η3 decreases. Conversely, as the thickness of the AFFs increases and the trailing edge shape transitions from blunt to elliptical and finally to round, η3 significantly increases while η1 decreases. Furthermore, when changes focus mainly on the leading edge of the AFFs, η3 improves without markedly affecting η1. Compared to the traditional airfoil channel, the η1 of the Fin-b channel increases by 3.1%-10.8%, demonstrating its greater suitability under identical flow rate conditions. Similarly, the η3 of the Fin-g channel is 1.4%-11.6% higher than that of the traditional airfoil channel, highlighting its superior performance under identical pumping power conditions. The present work provides a valuable reference for optimizing the design of AFF PCHEs under identical flow rate and pumping power conditions.

Retraction Note: Comment on, "Computed tomography based evaluation of the association between sphenoid sinus pneumatization patterns and variations of adjacent bony structures in relation to age and gender".

Retraction Note: Comment on, "Computed tomography based evaluation of the association between sphenoid sinus pneumatization patterns and variations of adjacent bony structures in relation to age and gender".

Characteristic Structure of the Relationships Among Depression, Maladaptive Cognition, and Internet Addiction and Its Temporal Evolution in University Students: A Network Analysis.

This study explored the structure and temporal evolution of the relationship among depression, maladaptive cognition, and internet addiction (DMI) among university students by focusing on topological and dynamic properties in a network analysis. A 3-year longitudinal survey was conducted with 873 university students (Mage=18.32, SD=0.74). The results of network analysis showed "compulsive internet use and withdrawal symptoms" as part of internet addiction and "depressive emotions" as part of depression were the core characteristics in the DMI relational structure. Additionally, "compulsive internet use and withdrawal symptoms" was most pronounced for freshmen, whereas "depressive emotions" were most pronounced for sophomores and juniors. These findings suggest that interventions addressing DMI among university students should not only focus on the key aspects of "compulsive internet use and withdrawal symptoms" and "depressive emotions," but also consider differences between students at different years of study.

Primary identification, symbolisation and the talking cure

ABSTRACT The aim of this study is to develop how speech and symbolization is connected to the concept of a primary identification, and how it affects our work. My main interest is how speech works and functions, or not functions in the analytic setting. I will investigate the concept of primary identifikation mainly from Julia Kristeva’s elaborations of what Freud writes in The Ego and the Id. I will also connect this with Piera Aulagnier’s comparison between an identificatory and a delirious discourse. As a conclusion I would like to describe primary identification as an anchoring, binding, and giving life to the child as a speaking subject, made possible by the direct and immediate influence of the mothers speaking, loving, and desiring psyche connected to thirdness. In the more well-functioning neurotic patient, the talking cure makes it possible for speech to ‘sing’ and carry a libidinal cathexis directed to thirdness and change. On the other hand, in the borderline discourse, there is not enough symbolic space between what has been separated and disunited, speech lacks the shift of libido onto language. There are also a lack of object relational structures containing meaning and reasoning in speech and thinking.

Maintaining CMSO 2 properties on dynamic structures with bounded feedback vertex number

Let φ be a sentence of \(\mathsf {CMSO}_2 \) (monadic second-order logic with quantification over edge subsets and counting modular predicates) over the signature of graphs. We present a dynamic data structure that for a given graph G that is updated by edge insertions and edge deletions, maintains whether φ is satisfied in G . The data structure is required to correctly report the outcome only when the feedback vertex number of G does not exceed a fixed constant k , otherwise it reports that the feedback vertex number is too large. With this assumption, we guarantee amortized update time \(\mathcal {O}_{\varphi,k}{(\log n)} \) . If we additionally assume that the feedback vertex number of G never exceeds k , this update time guarantee is worst-case. By combining this result with a classic theorem of Erdős and Pósa, we give a fully dynamic data structure that maintains whether a graph contains a packing of k vertex-disjoint cycles with amortized update time \(\mathcal {O}_{k}{(\log n)} \) . Our data structure also works in a larger generality of relational structures over binary signatures.

SUFFICIENT CONDITIONS FOR LOCAL TABULARITY OF A POLYMODAL LOGIC

Abstract On relational structures and on polymodal logics, we describe operations which preserve local tabularity. This provides new sufficient semantic and axiomatic conditions for local tabularity of a modal logic. The main results are the following. We show that local tabularity does not depend on reflexivity. Namely, given a class $\mathcal {F}$ of frames, consider the class $\mathcal {F}^{\mathrm {r}}$ of frames, where the reflexive closure operation was applied to each relation in every frame in $\mathcal {F}$ . We show that if the logic of $\mathcal {F}^{\mathrm {r}}$ is locally tabular, then the logic of $\mathcal {F}$ is locally tabular as well. Then we consider the operation of sum on Kripke frames, where a family of frames-summands is indexed by elements of another frame. We show that if both the logic of indices and the logic of summands are locally tabular, then the logic of corresponding sums is also locally tabular. Finally, using the previous theorem, we describe an operation on logics that preserves local tabularity: we provide a set of formulas such that the extension of the fusion of two canonical locally tabular logics with these formulas is locally tabular.

The Iteration Number of the Weisfeiler-Leman Algorithm

We prove new upper and lower bounds on the number of iterations the \(k\) -dimensional Weisfeiler-Leman algorithm ( \(k\) -WL) requires until stabilization. For \(k\geq 3\) , we show that \(k\) -WL stabilizes after at most \(O(kn^{k-1}\log n)\) iterations (where \(n\) denotes the number of vertices of the input structures), obtaining the first improvement over the trivial upper bound of \(n^{k}-1\) and extending a previous upper bound of \(O(n\log n)\) for \(k=2\) . We complement our upper bounds by constructing \(k\) -ary relational structures on which \(k\) -WL requires at least \(n^{\Omega(k)}\) iterations to stabilize. This improves over a previous lower bound of \(n^{\Omega(k/\log k)}\) . We also investigate tradeoffs between the dimension and the iteration number of WL, and show that \(d\) -WL, where \(d=\lceil\frac{3(k + 1)}{2}\rceil\) , can simulate the \(k\) -WL algorithm using only \(O(k^{2}\cdot n^{\lfloor k/2\rfloor+1}\log n)\) many iterations, but still requires at least \(n^{\Omega(k)}\) iterations for any \(d\) (that is sufficiently smaller than \(n\) ). The number of iterations required by \(k\) -WL to distinguish two structures corresponds to the quantifier rank of a sentence distinguishing them in the \((k + 1)\) -variable fragment \(\mathsf{C}_{k + 1}\) of first-order logic with counting quantifiers. Hence, our results also imply new upper and lower bounds on the quantifier rank required in the logic \(\mathsf{C}_{k + 1}\) , as well as tradeoffs between variable number and quantifier rank.

Reckoning with God

Abstract This special section reflects upon how divine-human relations are shaped by the socioeconomic and political circumstances in which they are cultivated. The four articles treat God not as a rigidly defined, unchanging being borne of ageless scripture and theology, but a figure who emerges during people's self-reflection and through their interactions with others in specific settings. The articles explore how human engagements with the divine manifest across a myriad of post–Arab Spring communities, from Syrian Sunni refugees in Jordan to Shi'i Iranians who feel forsaken by their government and God, and from Beiruti Orthodox Christians running a charity clinic to Sunni Muslim women taking Islamic lessons in Dubai. A framework of divine-human relations structures these distinct contributions, and this introduction lays out how the articles intervene in debates around politics, agency, and temporality. Together, the articles offer insight not only into what religiosity and selfhood look like among (dis)believers in the Middle East today, but also what notions of God drive different kinds of (ir)reverence. They also accord ethnographic attention to God, an otherwise marginal figure in much scholarship on religion.

Sonographic Anatomy and Imaging of the Dorsal Thumb Tendons

ABSTRACTInjuries to the dorsal thumb tendons and related structures can result in impairment to thumb motion. Ultrasound imaging is useful in diagnosing structural change in the dorsal thumb tendons, branches of the superficial radial nerve, and the dorsal hood. A detailed knowledge of the anatomy, sonographic technique, and normal and abnormal sonographic appearances is required to appropriately identify pertinent findings to guide patient management.

Impact of Ex Vivo Bisphenol A Exposure on Gut Microbiota Dysbiosis and Its Association with Childhood Obesity.

Dietary exposure to the plasticiser bisphenol A (BPA), an obesogenic and endocrine disruptor from plastic and epoxy resin industries, remains prevalent despite regulatory restriction and food safety efforts. BPA can be accumulated in humans and animals, potentially exerting differential health effects based on individual metabolic capacity. This pilot study examines the impact of direct ex vivo BPA exposure on the gut microbiota of obese and normal-weight children, using 16S rRNA amplicon sequencing and anaerobic culturing combined methods. Results showed that direct xenobiotic exposure induced modifications in microbial taxa relative abundance, community structure, and diversity. Specifically, BPA reduced the abundance of bacteria belonging to the phylum Bacteroidota, while taxa from the phylum Actinomycetota were promoted. Consistently, Bacteroides species were classified as sensitive to BPA, whereas bacteria belonging to the class Clostridia were identified as resistant to BPA in our culturomics analysis. Some of the altered bacterial abundance patterns were common for both the BPA-exposed groups and the obese non-exposed group in our pilot study. These findings were also corroborated in a larger cohort of children. Future research will be essential to evaluate these microbial taxa as potential biomarkers for biomonitoring the effect of BPA and its role as an obesogenic substance in children.

Functional and Structural Changes in the Inner Ear and Cochlear Hair Cell Loss Induced by Hypergravity.

Gravitational changes have been shown to cause significant abnormalities in various body systems, including the cardiovascular, immune, vestibular, and musculoskeletal systems. While numerous studies have examined the response of the vestibular system to gravitational stimulation, research on functional changes in the peripheral inner ear remains limited. The inner ear comprises two closely related structures: the vestibule and cochlea. These components share similar structures and neural functions, highlighting the importance of investigating changes in auditory nerve cells in response to gravitational alterations. To address this gap, we studied the functional and structural changes in the inner ear following exposure to hypergravity stimuli. Our findings demonstrate changes in auditory brainstem responses (ABRs) in the cochlea. ABR recordings were used to analyze click thresholds, as well as the amplitude and latency of tone bursts. The click thresholds at all frequencies increased in the group exposed to hypergravity in the long term. Additionally, tone burst results revealed significantly reduced amplitudes at high frequencies and delayed latencies in the hypergravity models. Notably, greater hair cell loss was observed in the middle and basal turns of the cochlea, indicating that mid and high-frequency regions are more vulnerable to hypergravity stimulation. Furthermore, nerve damage on the cochlear surface was evident in subjects exposed to 4G stimulation for 4 weeks. These findings suggest that the inner ear and its neural activity can be functionally and structurally affected by prolonged exposure to hypergravity.

A Cognitive View on Prominence Relations

The present paper proposes a cognitive view on prominence relations of utterances by treating them as prosodic relations with weak-strong metrical structure. Considering this aspect, prosodic relations have a cognitive structure and a prominence structure, both of them reflecting the structures of cognitive relations generated at cortical level during the evocation of auditory objects corresponding to speech constituents. Ladd (2008) introduces two types of relations in the F0 contour description, prosodic and prominence relations, but we suggest a single type of relation between speech constituents, named prosodic relation, and consider it is in the same time a prominence relation due to its weak-strong metrical structure. In section 2, the paper presents the cognitive model of information structure by defining the categories used for the description of cognitive and prominence structures of prosodic relations. In section 3, the cognitive and prominence structures of four utterances of the word permit as noun and verb, in descending and ascending F0 contours, are compared with those of four utterances of certain small statements and questions having words as constituents. All the contours mentioned are useful for understanding how utterances can be decomposed into binary hierarchies of prosodic relations with local or global prominent (strong) constituent, aiming to motivate researchers to take into account the cognitive interpretation of F0 contours.

Cerebellar Mutism/Posterior Fossa Syndrome Following Resection of Posterior Fossa Tumor in Pediatric Patients: Assessing Pathophysiology, Risk Factors, and Neuroradiographic Features

Background Cerebellar mutism syndrome (CMS) is a postoperative syndrome of decreased speech seen in children associated with neurobehavioral abnormalities, the incidence of which is up to 40%. Objective To evaluate pediatric patients with posterior fossa tumors for incidence, clinical characteristics, pathophysiology, risk factors, and neuroradiographic features of this syndrome. Materials and Methods The study included 60 pediatric patients with a posterior fossa tumor who underwent surgery by a telovelar approach. Detailed pre- and postoperative clinical and radiological evaluations were done. Patients with CMS were analyzed and compared with those without mutism to find risk factors for CMS. The presentation and characteristics of cerebellar mutism were studied along with the following risk factors:The preoperative, immediate postoperative, and 1-year postoperative imaging results were reviewed to assess the neuroradiographic features in the two groups. Results The incidence of this syndrome was 20%. The mutism was accompanied by some neurobehavioral abnormalities (p-value = 0.05). The most significant finding was the presence of a period of cerebellar dysarthria after the resolution of the muteness (p-value < 0.001) in all cases. Brainstem and related structures' involvement was the most significant risk factor (p-value = 0.03). The presence of brainstem and peduncular edema in the immediate postoperative period (p-value = 0.04) and gross atrophy of posterior fossa structures at 1 year (p-value = 0.01) showed significance toward the development of CMS. There was delayed neurological recovery in patients with CMS with a poor Glasgow Outcome Score at 1 year of follow-up. Conclusion The clinical presentation of this syndrome in context with neuroradiographic features suggests that it results from transient impairment of the afferent and/or efferent pathways of dentate nuclei that are involved in initiating complex volitional movements and are associated with brainstem involvement of tumor and poor functional outcome.

Mechanical response of elevated bridge piles to adjacent deep excavation

In urban concentrated area, the disturbance caused by construction affects significantly the sustainability of adjacent existing structures. It is essential to capture the mechanical response of existing structures to adjacent deep excavation. The objective of this paper is to investigate the displacement and internal force behavior of elevated bridge piles (BP) subject to influence of deep excavation. A three-dimensional finite element model is established by taking the project of a deep excavation near elevated bridge as an example. The numerically calculated results agree well with the measured data, which verifies the established numerical model. On the basis of this model, the influence of deep excavation on the mechanical characteristics of adjacent piles is captured. The results show that the displacement, bending moment, and shear force of piles are sensitive to the excavation depth. Their magnitudes increase with the increase of excavation depth. When the excavation is completed, the maximum displacements of piles in horizontal direction and vertical direction are 2.3 mm and 10.05 mm, respectively. The maximum bending moment is 1,140.8 kN·m. The maximum and minimum shear forces are 1,206 kN and -2,282 kN, respectively. The piles are mainly under pressure. The maximum pressure is -13,116 kN. The axial force is not sensitive to the depth of excavation. The deformation and internal force of piles exhibit obvious spatial distribution characteristics, and the closer the distance to the middle of the long side of the deep excavation, the greater the value. The research results have a positive effect on the optimization of related engineering structures and the promotion of sustainable development in urban concentrated area.

Technostress, technosuffering, and relational strain: a multi-method qualitative study of how remote and digital work affects staff in UK general practice.

The introduction of remote and digital forms of working in UK general practice has driven the development of new routines and working styles. To explore and theorise how new forms of work have affected general practice staff. Multi-site, qualitative case study in UK general practice. Using longitudinal ethnography by researchers-in-residence, we followed 12 practices for 28 months (2021-2023). This core dataset was supplemented by workshops and stakeholder interviews. Data analysis applied theories from the sociology of work and socio-technical change. Staff made significant efforts to adapt to and embed digital services into their work. When technologies work well, they can offer improved convenience, efficiency, more comprehensive patient care, and workplace fulfilment for staff. However, for many clinical and administrative staff, compromises and frictions embedded in digitalised workplace routines and processes could also lead to job dissatisfaction, worsened wellbeing and misalignments with professional values and identities. We found that this workplace suffering caused relational strain between team members, impacting team cohesiveness and coordination. The digitalisation of working routines in UK general practice poses a unique challenge to the workforce, risking technostress, workplace suffering, and increased relational strain within and between teams. To embed the benefits of digitalisation, we must first improve practice teams' readiness for change, which includes strengthening practices' relational structures, which provide support during periods of adaptation. Practices must be empowered to determine a locally-appropriate configuration of digital tools and given the resources and time to adapt working routines.