bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation into cold extrusion preforming of tantalum alloy component using finite element method
Authors: Shu Dayu , Zhan Hong , Wu Hulin , Chen Qiang
Published: October 2024

In this work, stress-strain distribution and material flow law of tantalum alloy components in cold extrusion preforming and the influence of critical design factors have been synthetically investigated. Based on the ABAQUS/Explicit platform, a finite element (FE) model was established to study the cold extrusion preforming process and the numerical result agreed well with the experiment. The verified FE model was employed to reveal the influence of pivotal design factors (blank geometry parameter, friction factor between dies and billet and deformation speed) on the formability and forming load of tantalum alloy preform. The results show that the equivalent plastic strain from the upper surface to the lower surface increasingly decreases along the thickness direction of the preform; while along the radial direction, the strain shows the tendency of first increasing and then decreasing. The forming load increases with the improvement of the blank geometry parameter and the friction factor between dies and billet while keeping insensitive to the variation of the deformation speed. In cold extrusion preforming of tantalum alloy component, the optimal initial blank diameter, friction factor between dies and billet and deformation speed of billet are 50 mm, 0.1 and 10 mm/s, respectively.
Research and verification of in-orbit induction-assisted welding process for thermoplastic-composite materials
Authors: Yan Jiayong , Li Peng , Duan Yingjia , Wang Cunyi , Geng Chao , Zhang Lixin
Published: October 2024

High-performance thermoplastic composite materials are commonly used as structural materials in aerospace. This article proposes an electromagnetic induction welding method suitable for the quick connection of thermoplastic composite structures between longitudinal beams and web members of truss structures. Research on electromagnetic induction welding methods and a small welding tool was developed. The electromagnetic induction welding verification test for carbon fiber-reinforced thermoplastic composite materials was completed. The quick welding of the truss longitudinal beam and the web member has been achieved, and the results show that this method has high welding efficiency, the equipment easily achieves miniaturization, and is suitable for the welding of thermoplastic composite materials. The application of this method can lay the foundation for the quick welding of thermoplastic composite material structures.
Topology optimization of static ring of a spiral dehydrator
Authors: Cheng Qianqian , Zhao Jing , Wei Tianlu , Wang Shuangjun
Published: October 2024

The static ring of the static ring filter screen of the self-designed spiral dehydrator is studied. According to the load and constraint of the static ring in the working process, the maximum total deformation of the static ring is obtained. Aiming at the lightweight requirement of the static ring, topological optimization of the static ring is carried out by using the variable density method based on static analysis, and the mathematical model of optimization is established. After optimization, the reasonable structure of the static ring is obtained, and its static performance meets the working requirements. Under the normal working frequency excitation, the harmonic response analysis shows that the maximum amplitude of the static ring is 0.535 mm. After optimization, the static ring mass is reduced by 9.7%, and the lightweight effect is remarkable. The research results provide a feasible method for the lightweight design of static rings.
Transient numerical simulation and characteristic study of flow field in high-pressure piston pump
Authors: Zheng Xiaofeng
Published: October 2024

As the core component of a mechanical system, the performance of the hydraulic pump, the power output core of the machine, is of great significance for the functional implementation of engineering equipment. The fluid motion state of a plunger rotary axial pump during flow distribution is very complex, especially when the pump rotates at high pressure and speed. The cavitation phenomenon can cause abnormal sound and vibration, seriously affecting its efficiency and service life. Taking the high-pressure plunger rotary axial pump as the research object, a geometric model of the fluid medium in the flow channel inside the pump was established. The motion law and characteristics of the flow field inside the pump were revealed through numerical simulation, laying the foundation for optimizing and improving the internal structure and reducing cavitation damage.
Research on energy harvesting of bi-stable magnetoelastic piezoelectric cantilever beam
Authors: Zhao Xingfang , Chen Huaping , Jiang Fan , Qin Jian
Published: October 2024

This article designs and explores an innovative magneto elastic bistable piezoelectric cantilever beam power generation system, which cleverly integrates a magnetic repulsion mechanism to enhance energy harvesting efficiency and deeply considers the geometric nonlinear effects of the structure to further optimize performance. Specifically, the system achieves efficient capture and conversion of energy under specific conditions by constructing a bistable piezoelectric energy harvester (BPEH) based on magnetic repulsion. At the theoretical analysis level, this article accurately derives a strain relationship model that includes geometric nonlinear effects. The step is crucial for accurately describing the behavior of cantilever beams in complex dynamic environments. Furthermore, with the help of the generalized Hamiltonian principle and Lagrange equation, this paper successfully established the dynamic equation system of the BPEH, laying a solid theoretical foundation for subsequent numerical analysis and optimization design. In the numerical research section, this article systematically explores the influence of external force on the motion characteristics and energy harvesting performance of BPEH oscillators. The research results show that by adjusting to the optimal excitation amplitude, the energy conversion efficiency of BPEH has been significantly improved, verifying the effectiveness and superiority of the system design. In addition, this article also deeply discusses the complex impact of geometric nonlinearity on the performance of BPEH oscillators: Under weak geometric nonlinearity conditions, the oscillator exhibits a stable trap motion mode, which is conducive to stable energy harvesting. When geometric nonlinearity is enhanced to a certain extent, the system may exhibit large-scale chaotic motion characteristics, which poses challenges to the stability and efficiency of energy harvesting.
Failure analysis of bow loading hose under tensile and bending loads
Authors: Yang Tianxiao
Published: October 2024

Offshore crude oil offloading hoses are widely used in oil and gas transportation between the FPSO and oil tankers. The hoses are mainly affected by tensile and bending loads during the bow loading operation and are easily prone to failure under the combined tensile and bending loads. Based on this, the ABAQUS software was used to establish a nonlinear finite element model under tensile and bending loads and analyze the bending failure modes of the hose under different initial tensile loads. The results show that the crushing area of the hose under bending load occurs within the three-pitch range of the middle part of the hose. As the tensile load increases, the bending angle of the hose shows an increasing trend. Under different initial tensile loads, when the hose bend reaches 5.73°, the Von Mises stress of the hose helical wire reaches 766MPa. Appropriately increasing the initial tensile load will help avoid the ultimate collapse of the hose. The research results provide suggestions for the practical application of offloading delivery hoses.
Effect of blade parameters on lift performance of drum-type vertical cross-flow fan
Authors: Wang Sheng , Wang Xiaoyi , Chen Hang , Qiu Zhizhen
Published: October 2024

The drum-type vertical cross-flow fan represents a novel approach to fan-wing technology. By re-configuring the traditional cross-flow fan in a vertical orientation, the symmetrical end plate design on both sides is transformed into an asymmetric structure. This modification aims to harness and optimize the axial force generated. Accordingly, this study delves into the development of a drum-type vertical cross-flow fan model. Through numerical simulation, we assess the impact of blade parameters on lift performance. The findings highlight that factors such as blade inclination angle, blade shape, blade diameter, and blade quantity all exert influence on lift force. A blade tilt of 15° around the impeller’s rotation direction along the lower edge, for instance, amplifies lift force by 26.73%. Arc-shaped blades along the wall contribute to heightened lift, while an increase in impeller diameter leads to a significant lift augmentation. Moreover, the presence of additional blades induces peak lift values, elevating lift from 43.31 N to 58.37 N.
Multi-objective design optimization for aerodynamic performance of centrifugal compressor impeller
Authors: Li Chenpeng , Zhou Yijun , Li Yongzhe , Shao Qin
Published: October 2024

Enhancing the performance of the centrifugal compressor system by optimizing the geometric parameters of the impeller is essential for achieving high thermodynamic efficiency and reducing energy costs. This study proposes a multi-objective optimization design approach to improve the pressure ratio and efficiency of centrifugal compressor impellers. The method combines the advantage of numerical simulation with the response surface method so that a reduction of design effort can be achieved. The Krain impeller is used to validate the optimization platform. The benefit of the developed approach is two-fold. On the one hand, the optimized design increased the pressure ratio significantly to the initial design under different working conditions. On the other hand, the impeller approach offers a reference for designers to optimize the design better. The outcomes demonstrate the viability of the approach, and the integrated optimization platform is reliable.
Simulation analysis of flow and acoustic characteristics of exhaust muffler of rolling rotor compressor
Authors: Hu Zhihong , Zhang Chaolei , Chen Lixiao
Published: October 2024

To investigate the influence characteristics of the size and height of the muffler exhaust hole on its pressure loss and transmission loss, this paper constructs a finite element model of the muffler of the rolling rotor compressor, and conducts numerical simulation analysis on the acoustic performance and resistance characteristics of the model. The simulation results showed that as the height of the muffler increased, its internal pressure loss decreased significantly, and its ability to reduce low-frequency noise was also considerably improved. The increase in exhaust hole diameter will also reduce the pressure loss, but the pressure loss is very low after increasing the hole diameter. In the frequency range of 400 ∼ 850 Hz, the noise reduction effect of the muffler decreases with the increase of the aperture, and the influence of other frequency ranges on the transmission loss is very small. The research results have certain reference values for the design and structural optimization of mufflers.
Subwavelength quantum Hall spin effects in spatially elliptical coiled phononic crystals based on the local resonance principle
Authors: Li Shiwei , Chen Congying , Tang Qixiang
Published: October 2024

Aiming to obtain a spatial helical square lattice with a subwavelength structure and quantum spin Hall effect, we have designed a spatially coiled square lattice with a subwavelength structure and quantum Hall effect. By adjusting the angle θ to break its nonpoint group symmetry, the quantum spin Hall effect is obtained by inducing the inversion of the energy bands. This serves as a basis for investigating its edge states. Through this study, we obtain a second-order topological insulator with a one-dimensional edge and a two-dimensional corner state. Finally, we use the topological properties to study its energy loss in transmitting different paths. This demonstrates that paths of different topological phases have high energy transfer efficiency.
Kinematic analysis of 3-RSR&4R hybrid mechanism
Authors: Meng Zhiyong , Qi Yang
Published: October 2024

A hybrid mechanism features serial mechanism flexibility, a large workspace, parallel mechanism stabilization, and high carrying capacity, combining the advantages of series and parallel mechanisms. However, the positive kinematic analysis is more complex. Proposing a new hybrid mechanism 3-RSR&4R begins by describing the institutional characteristics. Second, the positive kinematics are analyzed according to the structural features and modeling positive solutions. Finally, it is verified by numerical arithmetic examples, comparing and analyzing the theoretical results with MATLAB simulation results. The results show that the constructed positive kinematic model is correct.
Temperature field simulation analysis for hot blast valve of blast furnace
Authors: Xu Honghai , Gao Jie
Published: October 2024

The hot blast valve of the blast furnace was studied, and combined with the theory of fluid-solid coupling heat transfer, Fluent software was used to simulate and analyze the temperature field of the hot blast valve of the blast furnace under two working conditions: fully opened and fully closed. The analysis result showed that during the fully opened condition of the hot blast valve, the highest temperature of the valve body reached 1, 332.3°C, which is located on the refractory surface of the hot-air valve duct. The highest temperature of the valve plate is 837.2°C, which is located on the refractory surface on the leeward side of the valve plate. During the fully closed condition, the highest temperature of the valve body is 1, 300°C, which is located on the refractory surface near the upwind side of the valve plate. The highest temperature of the valve plate is 839.9°C, which is located on the refractory surface on the windward side of the valve plate. During the opening-supplying-closing process of the hot blast valve, the temperature change at the bottom outer edge of the valve plate is up to 370°C. The research results have certain guiding significance for the overall structural design of hot blast valves, and provide data for the analysis of thermal deformation and structural strength of hot blast valves.
Simulation and analysis of firing accuracy of remote control weapon station
Authors: Jiao Renlei , Pan Xiaobin , Zhou Qiang , Di Fang
Published: October 2024

Muzzle disturbance and fire control system error are the main factors affecting the firing accuracy of remote control weapon stations. In order to study the influence of muzzle disturbance on firing accuracy, this paper establishes a rigid-flexible coupling dynamic virtual prototype model of a remote control weapon station based on finite element theory. On this basis, the firing accuracy of the weapon station under the effect of muzzle disturbance is simulated and analyzed, the fire control system error is calculated, and then the firing accuracy of the weapon system is obtained. Further on, compared with the firing accuracy test, the rationality of the system structure design and the accuracy of the fire control system design are verified.
Wear simulation of pin-on-disc sliding wear test
Authors: Xie Jinhua , Li Peng , Qian Zhenghua , Qian Zhi
Published: October 2024

In this paper, the wear simulation of the pin-on-disc sliding wear test was performed by using the FEA software Abaqus. The wear depth of the pin sample was obtained by using Abaqus/Python secondary development technology based on Archard wear theory to calculate the surface node wear depth and control the wear simulation process, and by using Abaqus/ALE adaptive meshing technology to update the surface contour and the mesh information. To obtain the wear rate coefficient and verify the validity of the present method, the pin-on-disc sliding wear test and simulation were carried out, and the wear depth of the pin sample was compared. Based on this method, the influence of different loads on the wear of the pin sample is studied. The results show that the wear depth of the pin sample at each load is not the same, and the wear depth increases with increasing load at an increasing rate.
A criterion for reflexivity of modules
Authors: Endo Naoki , Goto Shiro
Published: October 2024

Let

M
M

be a finitely generated module over a ring

Λ
\Lambda

. With certain mild assumptions on

Λ
\Lambda

, it is proven that

M
M

is a reflexive

Λ
\Lambda

-module, once

M
≅

M

∗
∗

M \cong M^{**}

as

Λ
\Lambda

-modules.
Multiplicity-free induced characters of symmetric groups
Authors: Turek Pavel
Published: October 2024

Let

n
n

be a non-negative integer. Combining algebraic and combinatorial techniques, we investigate for which pairs

(
G
,
ρ
)

(G,\rho )

of a subgroup

G
G

of the symmetric group

S
n

S_n

and an irreducible character

ρ
\rho

of

G
G

the induced character

ρ

↑

S
n

\rho \!\uparrow ^{S_n}

is multiplicity-free. As a result, for

n
≥
66

n\geq 66

, we classify all subgroups

G
≤

S
n

G\leq S_n

which give rise to such a pair. Moreover, for the majority of these groups

G
G

we identify all the possible choices of the irreducible character

ρ
\rho

, assuming

n
≥
73

n\geq 73

.
Power, Social Inequities, and the Conversational Theory
Authors: McKenna Michael
Published: October 2024

This chapter challenges P. F. Strawson’s claim that we all demand a reasonable degree of good will from one another. This is not true. Some from positions of disadvantage do not take themselves to be positioned to do so. Hence, from the resources of the conversational theory, it is argued that the interpretive bases used to manifest and recognize good or ill will in others are themselves settled by those in positions of privilege. If so, much of our practices might be morally compromised. Drawing on Cheshire Calhoun’s account of how to hold responsible seemingly innocent moral agents whose conduct bolsters patriarchal injustice, it is argued that our responsibility practices revealed in our acting within the range of morally acceptable practices involve dubious treatment of the less privileged. While the conversational theory might help with the diagnosis, it is granted that it can offer no prescriptions.
Robert Schumann's Leipzig Chamber Works
Authors: Hedges Brown Julie
Published: October 2024

Chapter 1 opens by surveying Schumann’s dynamic view of history, which posits an interdependent relationship between past, present, and future—a global theme of the book. The chapter introduces the Leipzig chamber repertory, its understudied status, and the special place it holds in Schumann’s progression as a composer. It explores the reception of these works, especially the long-held viewpoint that these works are more traditional and “objective” when measured against Schumann’s youthful, experimental output. The chapter explains why such a perception is problematic: it discourages listeners from discerning ties between Schumann’s earlier and later music, and it hinders appreciation for how he reworked older models in creative and successful ways, an argument supported by various examples discussed in subsequent chapters and summarized here. The chapter subsequently surveys additional listener-based perspectives in the book that relate to issues broached above: how artistic works by figures outside of music might provide new understandings of Schumann’s musical innovations, and how the nineteenth-century London reception of the chamber music reveals a new spin on whether Schumann was a traditionalist or progressive composer.
Schumann in Time
Authors: Hedges Brown Julie
Published: October 2024

Chapter 1 opens by surveying Schumann’s dynamic view of history, which posits an interdependent relationship between past, present, and future—a global theme of the book. The chapter introduces the Leipzig chamber repertory, its understudied status, and the special place it holds in Schumann’s progression as a composer. It explores the reception of these works, especially the long-held viewpoint that these works are more traditional and “objective” when measured against Schumann’s youthful, experimental output. The chapter explains why such a perception is problematic: it discourages listeners from discerning ties between Schumann’s earlier and later music, and it hinders appreciation for how he reworked older models in creative and successful ways, an argument supported by various examples discussed in subsequent chapters and summarized here. The chapter subsequently surveys additional listener-based perspectives in the book that relate to issues broached above: how artistic works by figures outside of music might provide new understandings of Schumann’s musical innovations, and how the nineteenth-century London reception of the chamber music reveals a new spin on whether Schumann was a traditionalist or progressive composer.
Introduction
Authors: Jagannathan Dhananjay
Published: October 2024

This introduction identifies the main question of the book—what kind of knowledge is practical wisdom (phronēsis) in Aristotle?—and presents the book’s core claim: that it is practical understanding. It then shows how this view can make sense of the disparate claims Aristotle makes about this superior form of ethical knowledge, while treatments of phronēsis as either an intuitive skill or as a body of scientific knowledge fall short. It goes on to highlight two key views that shape Aristotle’s practical epistemology: the idea that there is genuine knowledge in ethics, and that practical wisdom is the highest grade of knowledge in this domain. Finally, it provides a plan of the book and a summary of each chapter.
Ethical Experience in theNicomachean Ethics
Authors: Jagannathan Dhananjay
Published: October 2024

This chapter offers readings of important texts from the Nicomachean Ethics to defend five claims about Aristotle’s theory of ethical experience as a form of practical knowledge. These claims are the following: (1) ethical experience is a kind of practical knowledge, that is, knowledge of how to act in accordance with virtue; (2) ethical experience is a characteristic product of good habituation; (3) ethical experience constitutes a grasp of the basic facts in ethics—knowledge of ‘the that’ and not ‘the why’ to use Aristotle’s own language; (4) ethical experience equips the would-be inquirer with the starting points needed to appreciate and make good use of ethical claims and arguments; and (5) since the person with ethical experience lacks a grasp of the reason why, they fall short of the ethical understanding that belongs to the person of practical wisdom and which it is the task of ethical inquiry to foster.
Political Wisdom
Authors: Jagannathan Dhananjay
Published: October 2024

This chapter takes up Aristotle’s striking claim that practical wisdom (phronēsis) and political wisdom (politikē) are, in a sense, the same understanding. The key idea that the chapter develops is that the person of political wisdom has the very same grasp of practical universals that belong to the person of practical wisdom but deliberates about these in relation to the political community as a whole. As someone equipped with the totality of the virtues, the person of practical wisdom has an understanding of the common good, which is the collective flourishing of the citizens, as well as the deliberative excellence needed to bring it about. The simultaneously universal and practical character of the understanding that just is phronēsis is therefore clearly displayed in its manifestation as political wisdom. In this way, this final substantive chapter of the book helps confirm the view that has been developed in the preceding chapters.
Data needs for sea otter bioenergetics modeling
Authors: Griffen Blaine D , Klimes Lexanne , Fletcher Laura S , Thometz Nicole M
Published: October 2024

Sea otters are keystone predators whose recovery and expansion from historical exploitation throughout their range can serve to enhance local biodiversity, promote community stability, and buffer against habitat loss in nearshore marine systems. Bioenergetics models have become a useful tool in conservation and management efforts of marine mammals generally, yet no bioenergetics model exists for sea otters. Previous research provides abundant data that can be used to develop bioenergetics models for this species, yet important data gaps remain. Here we review the available data that could inform a bioenergetics model, and point to specific open questions that could be answered to more fully inform such an effort. These data gaps include quantifying energy intake through foraging by females with different aged pups in different quality habitats, the influence of body size on energy intake through foraging, and determining the level of fat storage that is possible in sea otters of different body sizes. The more completely we fill these data gaps, the more confidence we can have in the results and predictions produced by future bioenergetics modeling efforts for this species.
New control variates for pricing basket options
Authors: Jipreze Kam , Date Paresh
Published: October 2024

Accepted by: Giorgio Consigli

Accurate pricing of basket options, which are financial derivatives on multiple underlying assets, is a challenging and practically important task for financial institutions. We propose several new control variates for accurate, fast and efficient pricing of basket options. The first approach to deriving new control variates is the use of Hermite polynomial approximation of appropriate function of the underlying asset prices, which leads to a Black–Scholes-like analytic solution. This approach is new in the option pricing context and opens up new possibilities in derivative pricing. Further control variates are analytically derived using Jensen’s inequality in one case, and distributional properties of multivariate Wiener processes in other cases. All the newly proposed control variates are shown to lead to excellent variance reduction in numerical experiments based on realistic data. The proposed methods are novel, computationally simple and have a strong potential to replace more conventional methods, such as the geometric lower bound in simulation-based pricing of basket options and similar products used in financial risk management.
The move to 24/7 mechanical thrombectomy provision for ischaemic stroke: an observational study of the impact on referrals, activity, procedural efficacy, and safety at a supra-regional centre
Authors: Mortimer Alex , Flood Richard , Minks David , Crossley Robert , Wareham James , Cox Anthony , Goswami Amit , Dodd James , Grier Scott , Marsh Aidan , Bosnell Rose
Published: October 2024

Background

Health systems are striving to improve delivery of mechanical thrombectomy (MT) for ischaemic stroke. With the move to 24/7 provision, we aimed to assess (1) the change in referral and procedural frequency and timing, (2) reasons referrals did not proceed to MT, and (3) nocturnal procedural efficacy and safety.

Methods

This was an observational study comparing 12-month data for an extended daytime service (2021/2022, hours, 0800–2000) to that for a 12-month period delivering 24/7 cover (2023–2024). Nocturnal and daytime outcomes (rate of recanalisation using modified TICI scoring), extent of postprocedural infarction (using ASPECTS grading), rate of early neurological improvement (using 24-h NIHSS change), 90-day mortality, and complicating symptomatic intracranial haemorrhage (SICH) in the latter period were compared.

Results

Both referrals (432 to 851) and procedural caseload (191 to 403) approximately doubled with the move to 24/7 cover; 36% of procedures occurred overnight (n = 145). The dominant reasons for referrals not proceeding to MT were a large core infarct (n = 144) or absence of a large vessel occlusion on baseline imaging (n = 140). There were no significant differences in successful recanalisation (TICI 2B/3: 85.5% vs 87.1%, P = .233), rates of postprocedural ASPECTS≥7 (74.9% vs 75.8%, P = .987), early neurological improvement (NIHSS reduction ≥30%: 43.4% vs 42.4%, P = .917), 90-day mortality (19.6% vs 18.6%, P = .896), or SICH (1.9% vs 4.1%, P = .214) obtained for daytime vs nighttime hours.

Conclusion

24/7 MT provision has resulted in a rapid rise in the number of patients who may benefit from MT. This service can be provided with an acceptable safety profile during nighttime hours in a high-volume comprehensive UK centre.
Is the U.S. Supreme Court Facing a Crisis of Democratic Legitimacy? A Review Article
Authors: Kastellec Jonathan P
Published: October 2024

Kevin McMahon's A Supreme Court Unlike Any Other examines the extent to which the current Supreme Court—and its conservative supermajority—departs from earlier courts in the extent to which it suffers from a “democracy gap.” McMahon persuasively argues that the current Court is different for two reasons. First, most of the justices in the conservative majority were appointed by presidents who did not win the popular vote and/or were confirmed by senators who represented fewer voters than the senators who opposed them. Second, the homogenization of nominee experience and background has created a “judicial aristocracy” in which the justices are experientially far removed from the elected branches. One puzzle this account raises is why this democracy gap took so long to emerge, given the institutional design of the Court. But given the current polarized state of American politics, the same forces that brought us to the reality of the conservative supermajority are unlikely to abate for quite some time.
Betamethasone Exposure and Neonatal Respiratory Morbidity Among Late Preterm Births by Planned Mode of Delivery and Gestational Age
Authors: Clapp Mark A. , Li Siguo , Cohen Jessica L. , Gyamfi-Bannerman Cynthia , Knudsen Amy B. , Lorch Scott A. , Thaweethai Tanayott , Wright Jason D. , Kaimal Anjali J. , Melamed Alexander
Published: October 2024

OBJECTIVE:

To estimate the effect of late preterm antenatal steroids on the risk of respiratory morbidity among subgroups of patients on the basis of the planned mode of delivery and gestational age at presentation.

METHODS:

This was a secondary analysis of the ALPS (Antenatal Late Preterm Steroid) Trial, a multicenter trial conducted within the Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal–Fetal Medicine Units Network of individuals with singleton gestations and without preexisting diabetes who were at high risk for late preterm delivery (34–36 weeks of gestation). We fit binomial regression models to estimate the risk of respiratory morbidity, with and without steroid administration, by gestational age and planned mode of delivery at the time of presentation. We assumed a homogeneous effect of steroids on the log-odds scale, as was reported in the ALPS trial. The primary outcome was neonatal respiratory morbidity, as defined in the ALPS Trial.

RESULTS:

The analysis included 2,825 patients at risk for late preterm birth. The risk of respiratory morbidity varied significantly by planned mode of delivery (adjusted risk ratio [RR] 1.90, 95% CI, 1.55–2.33 for cesarean delivery vs vaginal delivery) and week of gestation at presentation (adjusted RR 0.56, 95% CI, 0.50–0.63). For those planning cesarean delivery and presenting in the 34th week of gestation, the risk of neonatal respiratory morbidity was 39.4% (95% CI, 30.8–47.9%) without steroids and 32.0% (95% CI, 24.6–39.4%) with steroids. In contrast, for patients presenting in the 36th week and planning vaginal delivery, the risk of neonatal respiratory morbidity was 6.9% (95% CI, 5.2–8.6%) without steroids and 5.6% (95% CI, 4.2–7.0%) with steroids.

CONCLUSION:

The absolute risk difference of neonatal respiratory morbidity between those exposed and those unexposed to late preterm antenatal steroids varies considerably by gestational age at presentation and planned mode of delivery. Because only communicating the relative risk reduction of antenatal steroids for respiratory morbidity may lead to an inaccurate perception of benefit, more patient-specific estimates of risk expected with and without treatment may inform shared decision making.
The Role of Natriuretic Peptides in Pericardial Fluid in Predicting Cardiovascular Disorders: A Systematic Review
Authors: El-Sherbini Adham H. , Zucker James , Sartor Cameron , Liblik Kiera , Cherif Ibrahim Ahmed , Hassanabad Ali Fatehi , Fernandez Angel Luis , El-Diasty Mohammad
Published: October 2024

Atrial and ventricular natriuretic peptides play an important role in the neurohormonal regulation of cardiac function. Plasma levels of these peptides may aid in the diagnosis and prognosis of different cardiac disorders, such as congestive heart failure, ischemic heart disease, and atrial fibrillation. However, the association between elevated pericardial fluid levels of natriuretic peptides and these clinical conditions has not been proven. Databases Medline, EMBASE, Cochrane, ClinicalTrials.gov, and Google Scholar were searched for primary studies evaluating atrial natriuretic peptide, B-type natriuretic peptide, and N-terminal-pro-B-type natriuretic peptide concentrations within the pericardial fluid in various cardiac disorders. A total of 1060 citations were screened, of which 38 studies underwent a full-text evaluation, and 10 were finally included in this review. Sample size varied across studies (n = 8–148), and there was a total of 577 patients across the 10 studies. Findings suggested that pericardial fluid levels of B-type natriuretic peptide and N-terminal-pro-B-type natriuretic peptide but not atrial natriuretic peptide, may correlated with the reported cardiac conditions. Our findings suggest that pericardial fluid levels of natriuretic peptides may correlate with some cardiac disorders such as congestive heart failure and atrial fibrillation. The addition of these peptides to the existing clinical risk stratification scores may be helpful in the early diagnosis and management of these conditions.
Intraoperative Cell Death Signs in Corneal Graft During Triple DMEK Surgery
Authors: Scherer Nicolas C. D. , Kassumeh Stefan , Dirisamer Martin , Luft Nikolaus , Priglinger Siegfried G. , Mayer Wolfgang J.
Published: October 2024

Purpose:

To report the occurrence of cell death signs in a corneal graft during preparation for Descemet membrane endothelial keratoplasty and intraocular lens implantation (triple DMEK) in a 65-year-old woman with Fuchs endothelial dystrophy (FED) who developed graft detachment in the postoperative course with the necessity of rebubbling 2 weeks after surgery.

Methods:

This is a case report.

Results:

DMEK graft preparation was conducted by an experienced surgeon using a no-touch liquid bubble dissection method with trypan blue for staining and bubble formation. Staining was applied right before beginning the preparation and unmasked very subtle signs of apoptosis running linear radially from the periphery to the center of the graft. By the end of preparation, those areas presented as clear visible staining streets. Graft transplantation and cataract surgery were completed using a SF6 gas bubble intracamerally. In the postoperative course, the patient developed relevant graft detachment requiring rebubbling. Hereafter, the patient showed a very good and stable outcome.

Conclusions:

Trypan blue staining during graft preparation revealed existing apoptosis areas. The aspect of unmasking and analyzing those areas in DMEK grafts might represent an interesting approach regarding the outcome of surgery and the prediction of postoperative complications. Moreover, this case might depict an advantage of surgeon-prepared transplants since the surgeon can directly see and evaluate the apoptosis doing preparation. Further research is necessary to examine possible correlations between the extent of apoptosis and surgery outcome.
Effects of Eye Bank Donor Age Expansion on Corneal Endothelial Cell Density and Surgeon Tissue Acceptance
Authors: Adebayo Ayobami , Nortey Andrea , Moon Jee Young , Gore Patrick , Livesay Tina , Bortzfield Griffin , Gibralter Richard P. , Chuck Roy S.
Published: October 2024

Purpose:

To investigate the effects of expansion in eye bank donor age from 75 to 80 years on corneal endothelial cell density (ECD) and surgeon acceptance rate of donated tissues.

Methods:

Conducted as a single-site retrospective analysis, the study examined 25,969 donor corneas from 2018 to 2022. After the increase in the donor age limit in August 2022, the sample included donors aged 2 to 75 years (n = 25,558) and 76 to 80 years (n = 411). Donor characteristics, corneal ECD, and tissue acceptance rates were compared across age groups stratified by 5-year intervals.

Results:

Increasing the donor age upper limit produced 411 more corneal donations, which resulted in 208 more surgeries. The average corneal ECD in donors between the ages of 71 and 75 years was 2349 cells/mm2 (95% CI, 2332–2367), and in donors between the ages of 76 and 80 years, the average corneal ECD was 2227 cells/mm2 (95% CI, 2159–2296). Our results demonstrated a lower average corneal ECD in the 76- to 80-year-old group in comparison with the 71- to 75-year-old group by 122 cells/mm2 (95% CI, 51–193, P < 0.001). Tissue from donors aged 71 to 75 years had a 48% surgeon acceptance rate, whereas tissue from those aged 76 to 80 years had a significantly lower 38% acceptance rate (P = 0.003).

Conclusions:

Corneas from donors of older ages are viable and suitable for use in transplant surgery but are significantly less likely to be selected by surgeons. Age bias by surgeons against older corneas is a possible reason for this finding and warrants further exploration.
Diagnostic value of trans recto-perineal ultrasound in perianal fistula; pre versus intraoperative findings: a comparative cross section study
Authors: Zakaria Reham , Amin Mohamed Mahmoud , Orban Yasser Ali , Elfwakhry Rabab Mahmoud , abo-alella Heba Alhussein
Published: October 2024

Background

perianal fistula is a common and annoying anal problem. It needs only surgery. Magnetic resonance imaging (MRI) is the best preoperative diagnostic tool, but it is demanding as it is expensive, time-consuming, and requires an experienced radiologist. Therefore, we endeavored to identify an alternative diagnostic tool that offers cost-effectiveness, efficiency, and accuracy. Subsequently, we conducted a comparative analysis between its preoperative outcomes and intra-operative observations.

Materials and Methods

This is a single-center comparative cross-section study held in the surgery department from September 2023 to March 2024. It included 93 patients with perianal fistulas who were diagnosed clinically and radiologically by trans-recto-perineal ultrasound and comparing preoperative ultrasound findings with intra-operative surgical findings.

Results

Trans-recto-perineal ultrasound demonstrated favorable sensitivity and specificity in diagnosing perianal fistulas. It exhibited accuracy in identifying external and internal openings, their locations, fistula branches, fistula types, and their relationship to anal sphincters, as well as the presence of abscess or fibrosis, with a significant statistical association (P-value <0.001).

Conclusions

Trans-recto-perineal ultrasound is an accurate, fast, and cheap diagnostic tool for perianal fistula; however, it can be used as an alternative to perianal MRI.
Psychometric properties and diagnostic performance of three dry eye questionnaires in Italian: OSDI, OSDI-6, and SPEED
Authors: Facchin Alessio , Boccardo Laura
Published: October 2024

SIGNIFICANCE

Psychometric questionnaires are highly valuable instruments in clinical practice as they make subjective symptoms easier to measure. Recently, a short version of the Ocular Surface Disease Index (OSDI) questionnaire was developed, named OSDI-6.

PURPOSE

This study aimed to assess the psychometric properties and compare the diagnostic criteria of three questionnaires, available in the Italian language, designed for assessing dry eye disease: Standard Patient Evaluation of Eye Dryness (SPEED), OSDI-12, and specifically the new shortened version, OSDI-6.

METHODS

Psychometric evaluations were conducted on 250 adult participants aged 20 to 83 years. Classic and Rasch psychometric analyses were performed on the three questionnaires. The repeatability of the questionnaires was assessed by retesting 120 participants.

RESULTS

The exploratory factor analysis of OSDI-6 indicated saturation on two factors. Repeatability was optimal for all three questionnaires. Based on the reference OSDI-12, the cutoff for OSDI-6 was 5 points and 7 for SPEED. Rasch analysis showed that OSDI-6 and OSDI-12 present disordered response categories and thresholds. Conversely, the SPEED questionnaire shows the optimal item characteristic curve.

CONCLUSIONS

The OSDI-12 is a reference questionnaire used in dry eye disease studies and clinics, but OSDI-6 does not represent a perfect shortened version, primarily for the absence of one factor measured and secondarily for the same problem of category response order and thresholds. Conversely, SPEED focusing only on symptoms showed better psychometric properties.
Physiological Gallbladder Accumulation on 68Ga-FAPI-46 PET/CT
Authors: Şahin Ömer Faruk , Alçın Göksel , Ergül Nurhan , Çermik Tevfik Fikret , Arslan Esra
Published: October 2024

Radiolabeled fibroblast activation protein inhibitors (FAPIs) are a novel approach in cancer detection and treatment. Targeting fibroblast activation protein, extensively produced by cancer-associated fibroblasts, FAPI plays a key role in tumor development. Its advanced imaging capabilities offer clearer results in solid tumors compared with traditional methods, drawing significant interest in oncology. Additionally, FAPI’s activity in conditions requiring tissue remodeling, such as atherosclerosis and arthritis, highlights its broader potential. This interesting image shows the physiological accumulation of 68Ga-FAPI in the gallbladder, emphasizing the importance of accurate interpretation to prevent misdiagnoses and ensure effective patient management.
Complete genome identified of clinical isolate Prototheca
Authors: Li Juanjuan , He Xiaorong , Guo Hongen , Lin Damin , Wu Xiaomo , Chen Borui
Published: October 2024

Introduction.
Prototheca is an opportunistic pathogen that can infect both humans and animals, of which Prototheca wickerhamii (P. wickerhamii) being the most significant pathogenic green algae.

Gap statement. The incidence of human diseases caused by Prototheca has been on the rise, yet there is a significant gap in genetic research pertaining to the pathophysiological aspects of these infections.

Aim. The aim of this study is to present the whole genome data from the clinical isolate InPu-22_FZ strain and to understand its genomic characteristics through comparative genomic analysis and phylogenetic tree analysis. Functional annotation of protein-coding genes and analysis of their pathogenicity are also conducted.

Methodology. We described the high-quality de novo genome assembly of the clinical isolate InPu-22_FZ strain, achieved by combining Nanopore ONT and Illumina NovaSeq sequencing technologies. Phylogenetic tree was constructed to study the evolutionary relationship between the InPu-22_FZ strain and other species. The average nucleotide identity (ANI) analysis was used to assess the similarity between different species. Additionally, the size, distribution and composition of synteny blocks were also analysed to infer the evolutionary relationships of the genomes.

Results. The size of the assembled nuclear genome was 18.47 Mb with 48 contigs. Key features of the genome include high overall GC content (63.31%), high number (5478) and proportion (62.24%) of protein-coding genes and more than 96.71% of genes annotated for gene function. Phylogenetic analyses showed that the InPu-22_FZ strain and other P. wickerhamii clustered into one clade with a bootstrap value of 99% and collinearity analysis revealed high levels of collinearity with ATCC 16529. The ANI analysis revealed only a relatively high similarity (89–93%) to available P. wickerhamii genomes, suggesting the overall genomic novelty of InPu-22_FZ strain. Interestingly, the analysis of the pathogen–host interaction database unveiled and demonstrated reduced virulence of this strain, albeit it was isolated from a chronic upper-limb cutaneous infection.

Conclusion. The study provides an in-depth insight into the genomic structure and biological function of the InPu-22_FZ strain, revealing the genetic basis of its pathogenicity and virulence.
Emergence of drug-resistant Elizabethkingia anophelis clinical isolates in Myanmar
Authors: Tada Tatsuya , Oshiro Satoshi , Mizutani Naeko , Sato Koji , Hom Nang Sarm , Soe Pan Ei , Htoon Thi Thi , Tin Htay Htay , Kirikae Teruo
Published: October 2024

Seven drug-resistant Elizabethkingia anophelis isolates were obtained from inpatients in three medical settings in Myanmar between February 2017 and January 2021. All isolates were resistant to β-lactams and colistin. Among these, four isolates were resistant to amikacin with minimum inhibitory concentration (MIC) of ≥64 µg ml−1. Six of the seven isolates harboured genes encoding intrinsic β-lactamases, including bla
B, bla
CME and bla
GOB, whereas one isolate harboured bla
B, bla
CME and an incomplete bla
GOB gene. Phylogenetic analysis based on whole-genome sequences revealed that several E. anophelis isolates in Myanmar formed their own clusters, whereas others were similar to isolates found in the USA. This is the first report of the emergence of Elizabethkingia species in Myanmar.
The end of protein structure prediction: Improving prediction accuracy in chimeric proteins by windowed multiple sequence alignment
Authors: Vedula Sanketh , Bronstein Alex , Marx Ailie
Published: October 2024

AlphaFold2 has predicted the structures of almost every known protein. A simple means to create proteins beyond those found in nature, is by unnaturally fusing together two known proteins. Here we demonstrate that dependence on multiple sequence alignment, limits the success with which AlphaFold and ESMfold capture such chimeric forms of otherwise well predicted, individual, proteins. Specifically we show that peptides are predicted with significantly reduced accuracy when added to the terminalendsof scaffold proteins. Appending the multiple sequence alignment for the individual peptide tags to that of the scaffold protein often restores prediction accuracy.