bluuebunny/crossref_metadata_2025_split huggingface dataset:
Democratic contestation, organised labour, and pension reform in Ghana and Malawi
Authors: Morse Yonatan L. 
Published: October 2023

AbstractWhat explains variation in African states' commitment to pensions? This article argues that differences in the structure of contestation and legacies of state‐labour relations matter. When competition is confined to fewer and more stable parties, social welfare appeals gain currency to mobilise swing voters and makes it more likely that pensions will become a subject of political competition. However, legacies of labour accommodation can strengthen certain elements of pension reform, but also reinforce certain policy mindsets such as contributory insurance. These ideas are developed with case studies of Ghana and Malawi. The cases utilise process‐tracing evidence to demonstrate how specific structures of contestation and labour legacies led to divergent pathways of pension reform. The article highlights the significant challenges involved in strengthening pensions in Africa, and therefore the limited potential for a reconstitution of state‐citizen relations based on pension access.
Oman's trade achievements with Singapore given the Gulf–Singapore Free Trade Agreement
Authors: Gani Azmat 
Published: October 2023

AbstractOman's trade performance achievements with Singapore are assessed within the Gulf–Singapore Free Trade Agreement (GSFTA) framework. Since coming into force in January 2015, Oman's total export value to Singapore has plunged significantly. The number of imported products from Singapore remained significantly higher than the number of Oman's exports to Singapore, confirming that Omani exports have a weaker presence in the Singaporean market. In the post‐2015 period, Oman's export partner share in trade remained below its import partner share. Although Oman's comparative advantage strengthened in consumer goods, intermediate goods, chemicals and metals since 2015, animals, food, vegetables and wood consistently revealed their comparative disadvantage since 2000. Between 2015 and 2018, Oman's export share of capital and intermediate goods to Singapore fell from 45.23% to 33.57%, while it rose for consumer goods, chemicals, fuels, machinery and electrical products. Oman's trade reforms have resulted in weighted average tariffs on all products falling from around 5% in 2005 to below 0.60% in 2018. While GSFTA has delivered on expanding trade between Oman and Singapore (though with different magnitudes), it has fallen short of delivering the ‘level playing field’ as expected of Oman's bilateral trade.
Research and Optimization on the Exhaust Flow Characteristics Based on Energy-Splitting Method of the Low-Speed Marine Diesel Engine
Authors: He Fengshuo , Feng Xinlei , Pan Zhenjia , Zhou Gongjie , Lu Yong 
Published: October 2023

Abstract
In this study, an optimization scheme for exhaust flow characteristics based on the energy-splitting method is proposed. The low-speed marine diesel engine adopts the exhaust energy-splitting method during the exhaust process. Based on this, a one-dimensional calculation model, a three-dimensional calculation model, and a three-dimensional model of the gas collection box are established. After splitting, the vortex structure in the same phase of the gas collection box has a larger scale, higher flowrate, more significant entropy increase, and more severe turbulence dissipation. The length and diameter of the high-grade gas collection box are optimized. The results show that after optimization, the flow energy dissipation brought by the vortex structure is reduced, and the outlet pressure and flow velocity of the gas collection box are increased.
Corrosion Behavior of 20G Steel in Saline (Na2SO4) Circumstances at High Temperature/Pressure
Authors: Li Ruiyu , Bai Bing , Deng Lei , Che Defu 
Published: October 2023

Abstract
To study the corrosion characteristic of 20G steel in saline circumstances with sodium sulfate (Na2SO4), a series of corrosion experiments are implemented on a novel setup. The corroded steel samples are analyzed by X-ray photoelectron spectroscopy and X-ray diffraction. The results indicate that the effect of salinity on corrosion products in the gas phase is greater than that in the liquid phase. FeOOH is easier to form in the liquid phase than in the gas phase. The salinity of steam could promote the generation of Fe2O3. The relative content of Fe2O3 within the corrosion products that contained Fe in the gas/liquid phase increases from 49.68%/36.30% (Na2SO4 concentration in solution, c = 0) to 95.70%/74.55%, separately (c = 4 g L−1). The salinity has an inhibiting effect on the generation of FeOOH. In deionized water, the relative contents of FeOOH within the corrosion products that contained Fe are 36.01% (gas phase) and 56.43% (liquid phase), respectively. FeOOH hardly occurs as c = 4 g L−1. For corroded surfaces in Na2SO4 deposit, the main compositions detected are iron oxides (Fe2O3 and Fe3O4) and iron (Fe).
Evaluation of the Fracture Toughness of Short Carbon Fiber Reinforced Thermoplastic Composites
Authors: Shi Jianfeng , Zong Xinwei , Jiang Weili , Yao Riwu , Zheng Jinyang 
Published: October 2023

Abstract
Short carbon fiber (SCF) reinforced thermoplastic composites (SCFRTCs) are attracting broad attention in various fields for their excellent mechanical properties. The fracture toughness, an essential characteristic of the resistance of materials to crack propagation, is considered a critical aspect of the long-term performance of SCFRTCs structures. The fracture toughness of SCFRTCs depends on two competing mechanisms: the interface between SCFs and polymer matrix may promote crack initiation, while the SCFs hinder the crack propagation. In this study, the fracture toughness of SCFRTCs with varying SCFs volume fractions is first determined by a three-point bending test. The results show that adding SCFs effectively improves the fracture toughness of SCFRTCs, and an increase of up to 73.7% at the SCFs volume fraction of 5.45 vol%. In addition, it is found that heat treatment and its temperature have no effect on the fracture toughness of SCFRTCs. Subsequently, the full-field strain around the crack tip is analyzed by digital image correlation (DIC), and the strain level significantly decreases after adding SCFs. The fracture surface of the SCFRTCs specimen is much rougher compared with HDPE, and obvious bridging SCFs are observed, which make it to absorb more energy for fracture, thus explaining the toughening mechanism of SCFs on SCFRTCs.
Kinematic Design and Prototyping of a Gripper With Grasping and Scooping Capabilities Driven by the Redundant Degrees of Freedom of a Parallel Robot
Authors: Beaulieu Charles-Antoine , Nguyen Tan-Sy , Laliberté Thierry , Gosselin Clément 
Published: October 2023

Abstract
A gripper design is adapted to offer grasping and scooping capabilities to a parallel robot. This enables the parallel robot to manipulate not only large objects, but also thin objects lying on flat surfaces. Moreover, this gripper is driven directly by the redundant degrees of freedom of the parallel robot to which it is integrated. Thus, by eliminating actuators from the gripper, weight is drastically reduced, thereby making it possible to take advantage of the full payload of the parallel robot. The kinematic architecture of the gripper is first presented, notably, the kinematic implications of using an epicyclic mechanism. Then, the kinematic model developed to integrate the gripper to a (6 + 3)-degree-of-freedom robot is presented. Trajectory planning strategies for both grasping and scooping are then presented together with the parameters used. Finally, the experimental validation of these manipulation methods is discussed briefly to assess foreseeable improvements to the gripper itself as well as the trajectory planning aspect of the manipulation methods.
Effects of Reynolds Number and Tooth Front Angle on Leakage Loss and Heat Transfer Characteristics in a Rotating Labyrinth Seal
Authors: Yang Shaoyun , Du Wei , Luo Lei , Wang Songtao 
Published: October 2023

Abstract
The labyrinth seal is effective in reducing leakage losses at the rotor blade top in the turbine. This study investigates the variation in labyrinth seal performance at different rotational speeds, different Reynolds numbers, and different tooth front angles. Three Reynolds numbers (Re = 6000, 10,000, 15,000), five rotational speeds (Ta/Re = 0, 0.01, 0.04, 0.08, and 0.1), and three tooth front angles(75 deg, 90 deg, and 102.4 deg) have been introduced. The variation of leakage losses and heat transfer under different conditions is compared and a detailed analysis of the flow field and energy losses is performed. The discharge coefficient is increased slightly with increased rotational speed for the same Reynolds number. This is caused by the high rotational speed reducing the throttling loss and vortex loss. The high rotational speed enhances the heat transfer at the tip wall of the passage, and also weakens the heat transfer at the tooth cavity bottom. Additionally, the sealing capacity of the labyrinth is better at large tooth front angles, which is caused by the reduction of frictional losses on the stator and eddy current losses in the tooth cavity. The change in local pressure loss also affects the velocity distribution along the channel, which is the reason for the change in the local Nusselt number.
Multi-Objective Optimization of Air-Cooled Perforated Micro-Pin Fin Heat Sink Via an Artificial Neural Network Surrogate Model Coupled With NSGA-II
Authors: Gupta Deepa , Saha Probir , Roy Somnath 
Published: October 2023

Abstract
This research aims to create an artificial neural network (ANN) regression model for predicting the performance parameters of the perforated micro-pin fin (MPF) heat sinks for various geometric parameters and inflow conditions. A three-dimensional computational fluid dynamics (CFD) simulation system is developed to generate dataset samples under different operational conditions, which are specified using Latin hypercube sampling (LHS). An ANN model is first obtained by optimizing the model hyper-parameters, which are then deployed to learn from the input feature space that consists of perforation diameter, perforation location, and inflow velocity. For accurate training of the ANN, the model is trained over a range of uniformly distributed data points in the input feature space. The developed multi-layer model predicted Nusselt number and friction factor with the mean absolute percentage error of 4.45% and 1.80%, respectively. Subsequently, the developed surrogate model is used in the optimization study to demonstrate the application of the surrogate model. A multi-objective non-dominated sorting genetic algorithm (NSGA-II) is used to perform the optimization of the perforation location, diameter, and inflow conditions. Negative of the Nusselt number and friction factor are chosen as objectives to minimize. A Pareto front is obtained from the optimization study that shows a set of optimal solutions. Thermal performance of the perforated MPF is increased between 11.5% and 39.77%. The optimizer selected a significantly smaller hole diameter at a higher location and a faster speed to maximize the Nusselt number and minimize the friction factor.
Deep Learning–Based Time-Series Classification for Robotic Inspection of Pipe Condition Using Non-Contact Ultrasonic Testing
Authors: Hespeler Steven C. , Nemati Hamidreza , Masurkar Nihar , Alvidrez Fernando , Marvi Hamidreza , Dehghan-Niri Ehsan 
Published: October 2023

Abstract
This journal paper explores the application of Deep Learning (DL)-based Time-Series Classification (TSC) algorithms in ultrasonic testing for pipeline inspection. The utility of Electromagnetic Acoustic Transducers (EMAT) as a non-contact ultrasonic testing technique for compact robotic platforms is emphasized, prioritizing computational efficiency in defect detection over pinpoint accuracy. To address limited sample availability, the study conducts benchmarking of four methods to enable comparative evaluation of classification times. The core of the DL-based TSC approach involves training DL models using varied proportions (60%, 80%, and 100%) of the available training dataset. This investigation demonstrates the adaptability of DL-enabled anomaly detection with shifting data sizes, showcasing the AI-driven process's robustness in identifying pipeline irregularities. The outcomes underscore the pivotal role of artificial intelligence (AI) in facilitating semi-accurate but swift anomaly detection, thereby streamlining subsequent focused inspections on pipeline areas of concern. By synergistically integrating EMAT technology and DL-driven TSC, this research contributes to enhancing the precision and near real-time inspection capabilities of pipeline assessment. This investigation collectively highlights the potential of DL networks to revolutionize pipeline inspection by rapidly and accurately analyzing ultrasound waveform data.
Ubiquitin E3 ligase SPOP is a host negative regulator of enterovirus 71-encoded 2A protease
Authors: Zang Lichao , Yang Xinyu , Chen Yan , Huang Fan , Yuan Yukang , Chen Xiangjie , Zuo Yibo , Miao Ying , Gu Jin , Guo Hui , Xia Wenxin , Peng Yang , Tang Mengyuan , Huang Ziwei , Wang Yangyang , Ma Jinhong , Jiang Jingting , Zhou Wei , Zheng Hui , Shi Weifeng 
Published: October 2023

ABSTRACT

The 2A protease (2A
pro
) encoded by enterovirus 71 (EV71) serves as an accessory protein with significant involvement in the regulation of EV71 infection and viral replication. EV71-2A
pro
exhibits the ability to suppress various host factors, thereby disrupting the cellular antiviral immune response. However, whether host factors downregulate EV71-2A
pro
remains largely unknown. Here, we discovered that the speckle-type POZ protein (SPOP), functioning as a host E3 ubiquitin ligase, triggers ubiquitination modifications and subsequent degradation of EV71-2A
pro
. SPOP interacts with EV71-2A
pro
and exhibits a dose-dependent downregulation of EV71-2A
pro
levels. Conversely, knockdown of endogenous SPOP upregulated EV71-2A
pro
levels. Subsequent investigations revealed that the SPOP facilitates the lysosome-dependent degradation of EV71-2A
pro
by inducing K48-linked polyubiquitination of EV71-2A
pro
, which ultimately restricts EV71 replication. These findings shed light on the ubiquitination and lysosome-dependent regulation of the crucial EV71-encoded protease, offering a potential therapeutic target for the treatment of EV71 infection.

IMPORTANCE

EV71 poses a significant health threat to children aged 5 and below. The process of EV71 infection and replication is predominantly influenced by ubiquitination modifications. Our previous findings indicate that EV71 prompts the activation of host deubiquitinating enzymes, thereby impeding the host interferon signaling pathway as a means of evading the immune response. Nevertheless, the precise mechanisms by which the host employs ubiquitination modifications to hinder EV71 infection remain unclear. The present study demonstrated that the nonstructural protein 2A
pro
, which is encoded by EV71, exhibits ubiquitination and degradation mediated by the host E3 ubiquitin ligase SPOP. In addition, it is the first report, to our knowledge, that SPOP is involved in the host antiviral response.
Kaposi’s sarcoma-associated herpesvirus glycoprotein K8.1 is critical for infection in a cell-specific manner and functions at the attachment step on keratinocytes
Authors: Liu Shanchuan , Großkopf Anna K. , Yang Xiaoliang , Mannheim Maximilian E. , Backovic Marija , Scribano Stefano , Schlagowski Sarah , Ensser Armin , Hahn Alexander S. 
Published: October 2023

ABSTRACT
Kaposi’s sarcoma-associated herpesvirus (KSHV) is associated with Kaposi’s sarcoma and B cell malignancies. K8.1, the major antigenic component of the KSHV virion, has been reported to play a critical role in the infection of B cells, but otherwise its function remains enigmatic. We created a K8.1 knockout virus (KSHVΔK8.1) in the BAC16 genetic background and analyzed its infectivity on a range of adherent cells. We observed a strong defect on several epithelial cells, such as the HaCaT keratinocyte cell line, human embryonic kidney (HEK) 293T, and A549 lung epithelial cells. However, we did not observe such a defect in other cells, including lymphatic and blood endothelial cells. Mechanistically, we found that reduced infectivity of the K8.1 knockout virus correlated with reduced attachment to HaCaT cells. The defect in infectivity of KSHVΔK8.1 could be rescued by complementation through expression of K8.1 in KSHVΔK8.1 producing cells by means of a lentiviral vector. In a coculture infection model with iSLK producer cells, KSHVΔK8.1 was highly efficient at infecting the BJAB B cell line but was significantly impaired at infecting the MC116 B cell line, in line with a previous report. In fusion assays together with the gH/gL glycoprotein complex and gB, the components of the conserved herpesviral core fusion machinery, we did not observe activation of membrane fusion by K8.1 or its R8.1 homolog of the rhesus monkey rhadinovirus. In summary, we found K8.1 to function in a highly cell-specific manner during KSHV entry at the attachment step, playing an important role in the infection of epithelial cells.

IMPORTANCE
Kaposi’s sarcoma-associated herpesvirus (KSHV) is the causative agent of several B cell malignancies and Kaposi’s sarcoma. We analyzed the function of K8.1, the major antigenic component of the KSHV virion in the infection of different cells. To do this, we deleted K8.1 from the viral genome. It was found that K8.1 is critical for the infection of certain epithelial cells, e.g., a skin model cell line but not for infection of many other cells. K8.1 was found to mediate attachment of the virus to cells where it plays a role in infection. In contrast, we did not find K8.1 or a related protein from a closely related monkey virus to activate fusion of the viral and cellular membranes, at least not under the conditions tested. These findings suggest that K8.1 functions in a highly cell-specific manner during KSHV entry, playing a crucial role in the attachment of KSHV to, e.g., skin epithelial cells.
Differential adenine methylation analysis reveals increased variability in 6mA in the absence of methyl-directed mismatch repair
Authors: Stone Carl J. , Boyer Gwyneth F. , Behringer Megan G. 
Published: October 2023

ABSTRACT

Methylated DNA adenines (6mA) are a critical epigenetic modification in bacteria that affect cell processes like replication, stress response, and pathogenesis. While much work has been done characterizing the influence of 6mA on specific loci, very few studies have examined the evolutionary dynamics of 6mA over long time scales. We used third-generation sequencing technology to analyze 6mA methylation across the
Escherichia coli
K-12 substr. MG1655 genome. 6mA levels were consistently high across GATC sites; however, we identified regions where 6mA is decreased, particularly in intergenic regions, especially around the −35 promoter element, and within cryptic prophages and IS elements. We further examined 6mA in WT and methyl-directed mismatch repair-deficient (MMR-) populations after 2,400 generations of experimental evolution. We find that, after evolution, MMR- populations acquire significantly more epimutations resulting in a genome-wide decrease in 6mA methylation. Here, clones from evolved MMR- populations display non-deterministic sets of epimutations, consistent with reduced selection on these modifications. Thus, we show that characterization of 6mA in bacterial populations is complementary to genetic sequencing and informative for molecular evolution.

IMPORTANCE

Methylation greatly influences the bacterial genome by guiding DNA repair and regulating pathogenic and stress-response phenotypes. But, the rate of epigenetic changes and their consequences on molecular phenotypes are underexplored. Through a detailed characterization of genome-wide adenine methylation in a commonly used laboratory strain of
Escherichia coli
, we reveal that mismatch repair deficient populations experience an increase in epimutations resulting in a genome-wide reduction of 6mA methylation in a manner consistent with genetic drift. Our findings highlight how methylation patterns evolve and the constraints on epigenetic evolution due to post-replicative DNA repair, contributing to a deeper understanding of bacterial genome evolution and how epimutations may introduce semi-permanent variation that can influence adaptation.
Clinical
Staphylococcus aureus
inhibits human T-cell activity through interaction with the PD-1 receptor
Authors: Mellergaard Maiken , Skovbakke Sarah Line , Jepsen Stine Dam , Panagiotopoulou Nafsika , Hansen Amalie Bøge Rud , Tian Weihua , Lund Astrid , Høgh Rikke Illum , Møller Sofie Hedlund , Guérillot Romain , Hayes Ashleigh S. , Erikstrup Lise Tornvig , Andresen Lars , Peleg Anton Y. , Larsen Anders Rhod , Stinear Timothy P. , Handberg Aase , Erikstrup Christian , Howden Benjamin P. , Goletz Steffen , Frees Dorte , Skov Søren 
Published: October 2023

ABSTRACT

Staphylococcus aureus
(
S. aureus
) represents a major clinical challenge due to its explicit capacity to select mutations that increase antibiotic resistance and immune evasion. However, the molecular mechanisms are poorly defined, especially for adaptive immunity. Cancer immunotherapy targeting programmed cell death protein 1 (PD-1) enhances T-cell activity and is emerging for the treatment of certain viral infections, while its potential against bacterial infections remains elusive. We show that an
S. aureus clpP
mutant, selected during clinical antibiotic therapy, inhibits T-cell activity by directly interacting with PD-1 on human T cells. Specificity of the interaction was confirmed using recombinant PD-1, as well as PD-1 overexpressing and knock out cells. Moreover, the PD-1-binding
S. aureus
inhibited intracellular calcium mobilization, T-cell proliferation, CD25 expression, and IL-2 secretion, while the key effects were alleviated by antibody-mediated PD-1 blockade using an engineered IgG1-based anti-PD-1 antibody. Our results suggest that
clpP
mutant
S. aureus
directly targets PD-1 to evade immune activation and that therapeutic targeting of PD-1 may be used against certain staphylococcal infections.

IMPORTANCE

Therapies that target and aid the host immune defense to repel cancer cells or invading pathogens are rapidly emerging. Antibiotic resistance is among the largest threats to human health globally.
Staphylococcus aureus
(
S. aureus
) is the most common bacterial infection, and it poses a challenge to the healthcare system due to its significant ability to develop resistance toward current available therapies. In long-term infections,
S. aureus
further adapt to avoid clearance by the host immune defense. In this study, we discover a new interaction that allows
S. aureus
to avoid elimination by the immune system, which likely supports its persistence in the host. Moreover, we find that blocking the specific receptor (PD-1) using antibodies significantly relieves the
S. aureus
-imposed inhibition. Our findings suggest that therapeutically targeting PD-1 is a possible future strategy for treating certain antibiotic-resistant staphylococcal infections.