bluuebunny/crossref_metadata_2025 huggingface dataset:
Trustworthiness Evaluation Framework for Digital Ship Navigators in Bridge Simulator Environments
Authors: Namazi Hosna , Perera Lokukaluge Prasad
Published: September 2023

The maritime industry is going towards implementing digital navigators, i.e., AI created by machine learning algorithms, on autonomous vessels in the future. Digital navigators can be developed by utilizing machine learning algorithms, e.g., deep learning type neural networks trained by data sets from human navigators. Even though there is significant importance in studying the trustworthiness of these digital navigators, a proper framework to evaluate it has not yet been developed. This study identifies the appropriate key performance indicators (KPIs) in the trustworthiness of digital navigators in autonomous vessels.

The trustworthiness of AI-based applications, including digital navigators, can be studied from two primary levels: Software and hardware levels. Each of these levels must have certain characteristics to be called trustworthy. In other words, software codes and algorithms should be Transparent, i.e., Explainable, Fair, and Accountable/Responsible. Moreover, the trustworthiness at the hardware level can be elaborated under two concepts of Resilience and Availability of the relevant systems and technologies. In addition, some concepts, such as Reliability, Privacy, Security, and Safety, should be studied for both levels since those concepts can overlap in both software and hardware levels.

In this paper, the main focus is on investigating the software level’s trustworthiness. After an introduction on the importance of the topic and digital navigator’s development steps, the existing literature on trustworthy AI is reviewed, and the proper approaches for evaluating trustworthiness in AI-based digital navigators are identified and proposed.
RANS Simulations of Propeller-Hull Interaction in Model Scale With the Best-Practice Settings
Authors: Jin Shanqin , Peng Heather , Qiu Wei
Published: September 2023

Extensive convergence studies for the KCS hull model had been carried out, and the best-practice settings were summarized in our previous work [1]. Compared with the experimental results, the best-practice settings were verified in this work by applying them to simulations of the Japan Bulk Carrier (JBC) and KRISO Very Large Crude Carrier V.2 (KVLCC2) models. Bare-hull resistance and propeller open-water performance were first examined. For propeller-hull interaction, both the body-force method and the detailed propeller modelling method were applied to predict the wake fraction and propeller performance behind the hull. Furthermore, the pseudo effective wake fraction determined from CFD simulations was introduced and compared with experimental data.
Localization and Mapping for Deep-Sea Mining Vehicles With Forward-Looking Sonar
Authors: Xu Wenhao , Yang Jianmin , Wei Handi , Lu Haining , Tian Xinliang , Liu Lei
Published: September 2023

The deep-sea mining vehicle is one of the critical equipment of the deep-sea mining system, which is used to collect manganese nodules or other minerals on the seafloor. When the deep-sea mining vehicles works, a reliable localization system is essential. In addition, the ability to sense and model the surrounding environment in real time is also necessary for the safe and efficient operation for deep-sea mining vehicles. This study developed and validated a localization and mapping algorithm. The localization algorithm uses extended Kalman filtering fusing inertial measurement unit, ultrashort baseline, a compass, track encoders and forward-looking image sonar. The mapping algorithm relies on forward-looking image sonar and the position output by the localization algorithm. The environment map is a grid map to meet the requirements of obstacle avoidance and path planning for deep-sea mining vehicles. A deep-sea mining vehicle named ‘“Pioneer I” which was designed and developed by Shanghai Jiao Tong University has been tested in the South China Sea. All the data of sensors in the sea trials were recorded with time synchronization based on the software framework. Therefore, the sensor data from the sea trials can be used as input for validation of the proposed localization and mapping algorithm.
A Simplified Model of the Carcass Axial Capacity for Unbonded Flexible Pipes Under Differential Pressure Loading
Authors: Zhu Linfa , Liu Jian , Tan Zhimin , Roberts Andrew
Published: September 2023

The formation of hydrate plugs can lead to a significant operational risk to a flexible pipe when uncontrolled differential pressure builds up across a blockage. After a hydrate plug is completely formed, it can fill all the voids within the carcass profile and the gap between the carcass and pressure sheath layers. This bonding mechanism constrains the relative movement of the carcass and pressure sheath layers at the hydrate plug section. The axial end cap force from the differential pressure acts on the formed hydrate plug and the load is directly transferred to the carcass and pressure sheath layers. If large enough, this load could tear the carcass layer apart, and damage the pressure sheath layer which leads to catastrophic failure of the pipe structure. It is important to assess the limiting capacity of such failure mode to assure safe operation.

In this paper, a carcass axial capacity prediction model is presented for flexible pipes under differential pressure loading based on the characteristics of the deformations of the carcass and pressure sheath layers near the hydrate plug. The total axial capacity is predicted by the combination of a 2D finite element model for the carcass layer and a simplified analytical model for the pressure sheath layer. Detailed quantitative analysis results of a given flexible pipe are presented and compared with the test results. The design parameters impacting the model prediction are explored.
Numerical Simulation of the Deflection of Jellyfish due to Air Bubble Curtains
Authors: Liu Lei , Talimi Vandad , Thodi Premkumar , Gauthier David , Paris Mario
Published: September 2023

Increased jellyfish blooms have gained more attention recently due to their tendency to clog seawater intake systems of nuclear power plant cooling stations and threaten marine fish farms. The Bubble Tubing for Jellyfish Deflection Project (BTJD) was conducted by C-CORE to investigate the efficiency of Canadian Pond.ca’s Bubble Tubing® for jellyfish deflection. A three-dimensional Computational Fluid Dynamics (CFD) model was developed to quantify air bubble curtain performance for jellyfish deflection. The commercial CFD package STAR-CCM+ was used for this purpose. The multi-phase (water and air) fluid flow dynamics were simulated by solving Reynolds Averaged Navier Stokes (RANS) equation. The Discrete Element Modeling (DEM) approach was utilized to model the individual jellyfish behavior. The CFD model was initially used to optimize the flume tank test design, and then the model was validated using the test results from the flume tank. CFD simulations covered a range of test parameters such as current speed, number of curtains, curtain spacing, bubbler angles and air flow rates. Good agreement was observed between the CFD simulations and flume tank test results. The developed CFD model can be utilized for similar applications at field scales.
Buckling and Post-Buckling Behaviour of Extruded Aluminium Panels Subject to the Combined Effects of Welding and Pitting Corrosion
Authors: Mokhtari Mojtaba , Wang Xintong , Amdahl Jørgen
Published: September 2023

The present study investigates the effects of pitting corrosion and welding, both independently and combined, on the buckling and post-buckling behaviour of extruded aluminium panels. For this purpose, a finite element model of an aluminium panel made of AA6082-T6 extruded profiles is first developed without having the pitting corrosion and welding effects considered. Then, this finite element model is upgraded to account for the welding effects. This is followed by the validation of the upgraded model against the experimental data obtained from the literature. After the model validation, a hierarchical stochastic algorithm is utilised to simulate the pitting corrosion attack as geometrical defects distributed on the surface of both finite element models, with and without the welding-induced imperfections. Two different corrosion scenarios are considered. In the first scenario, the plating is corroded while the stiffeners remain intact. In the second scenario, the plating is intact, and the stiffeners contain pitting corrosion defects. The corroded parts are modelled with solid, hexahedral elements while shell elements are employed elsewhere. The effect of element type on the numerical results is discussed. Ultimately, the results obtained from the finite element models with and without corrosion and welding effects are compared in terms of ultimate strength, post-buckling response and stress/strain distribution.
RANS Simulations of Self-Propulsion Model Tests for a Fishing Vessel
Authors: Cilkaya Emre , Peng Heather , Qiu Wei
Published: September 2023

This paper presents the self-propulsion simulations for a fishing vessel with an optimized bulbous bow and a four-bladed fixed-pitch propeller using the RANS solver in the open-source Computational Fluid Dynamics (CFD) package OpenFOAM. Steady simulations were carried out at the design speed without a propeller to validate the bare-hull resistance results against the experimental data. The open-water hydrodynamic characteristics of the propeller were then simulated with the Moving Reference Frame (MRF). Finally, the self-propulsion simulations were performed by changing the propeller rotational speed with the same forward speed. The propeller thrust and torque coefficients were compared with the experimental data. Discrepancies between the experimental measurements and the numerical results on the towing forces were observed.
Developments of the Glen Lyon FPSO Digital Twin: Vessel Response and Structural Monitoring
Authors: Bailey Jonathan , Bamford Richard J. , Das Suvabrata , Maroju Soma S. , Barker Robert J.
Published: September 2023

This paper presents the continuing developments of the Glen Lyon FPSO Digital Twin. The objective of the Glen Lyon Digital Twin has always been to monitor and inform structural barrier health and verify operation within the allowable design limits. A detailed vessel motion response and loads monitoring is being undertaken to keep track of the fatigue life consumption of the hull structure, and to take mitigating actions as needed to maintain integrity. The structural response monitoring system onboard is contained within the vessel’s Integrated Marine Monitoring System (IMMS), which consists of various sensors, including accelerometers and strain gauges. The measurements from these are accessed and post-processed through BMT DEEP, harnessing the benefits of Digital Twin Technology, by bringing in data from all sources and enabling to synthesize and monitor the FPSO response in near real-time from any remote location.

The structural dashboard monitors the vessel dynamic stability, relative environment headings, and vessel offsets, through several statistical distribution charts. The hull girder bending moments are continuously monitored through deflections measured by the deck strain gauges. Also, the vessel fatigue damage is computed from the deck strain gauge measurements. Apart from these, the vessel motion responses like relative wave elevations and vertical accelerations at the turret center, are being utilized to help monitor vessel fatigue life consumption by comparison with established fatigue curves using these parameters. Comparisons are made with the predicted fatigue damage rates during the vessel design. Some key insights and findings from these comparisons are presented. The challenges faced in this process are highlighted, along with the steps taken to overcome those.
Performance Feasibility of a Multi-Source Offshore Renewable Energy Platform for Aquaculture
Authors: Roberts Sophie , Howe Damon , Nader Jean-Roch
Published: September 2023

The global aquaculture industry is facing new challenges as it strives to satisfy the continually growing demand for seafood products. The expanding industry brings with it challenges such as the diminishing availability of suitable coastal zones due to increased competition for marine-use areas, and a responsibility to limit negative impacts to the environment. As a potential solution to the negate environmental impact and continue industry expansion, operations are expected to transition further offshore. Moving aquaculture operations offshore presents several challenges, foremost of which is the provision of energy. This paper explores the feasibility of using a novel multi-source renewable energy platform to overcome the reliance on diesel in the offshore aquaculture industry. Through the development of a numerical model, this solution proposes a scalable renewable energy platform located off the coast of Tasmania utilising solar photovoltaic (PV), wind turbines and wave energy conversion. The feasibility is assessed through a numerical model based on factors such as resource availability, energy demand and conversion system efficiencies to determine how different design and resource variable influence the ability of the platform to meet the energy requirements.
Relating the Stiffness of Load-Transfer Functions for Monopile Foundations to Elastic Soil Modulus
Authors: Doherty James , Randolph Mark , Wan Xiao
Published: September 2023

Estimating the stiffness of large diameter monopiles used to support offshore wind turbines is an important step in the design process. This is generally done using load-transfer functions in the form of independent (Winkler) springs to represent the relationship between the net soil resistance at any depth adjacent to a pile (p) and the lateral deflection of the pile at the same depth (y). Recent studies for monopiles, which have low length to diameter ratios and high moment loading, have led to recommendations for additional moment-rotational, or m-θ, springs distributed along the shaft of the monopile, as well as base lateral and rotational springs. A significant challenge in applying these new recommendations is to relate the load-transfer functions to conventional soil properties. A simple ‘Step 0’ design approach has derived relationships between the initial stiffness values of the load-transfer functions and the elastic modulus of the soil at a given depth. In this paper, the accuracy of these relationships is examined for a more complex, layered soil profile that includes realistic but abrupt changes in soil modulus. It shown that once a soil modulus profile is established, a reasonably accurate estimate of the stiffness of a monopile can be obtained, sufficient for initial design calculations, without the need for more onerous 3D FEA.
Investigation of Theoretical Solutions to a Bottom-Raised Oscillating Surge Wave Energy Converter (OSWEC) Through Experimental and Parametric Studies
Authors: Nguyen Nhu , Davis Jacob , Thiagarajan Krish , Tom Nathan , Husain Salman
Published: September 2023

Experiments were conducted on a wave tank model of a bottom raised oscillating surge wave energy converter (OSWEC) model in regular waves. The OSWEC model shape was a thin rectangular flap, which was allowed to pitch in response to incident waves about a hinge located at the intersection of the flap and the top of the supporting foundation. Torsion springs were added to the hinge in order to position the pitch natural frequency at the center of the wave frequency range of the wave maker. The flap motion as well as the loads at the base of the foundation were measured. The OSWEC was modeled analytically using elliptic functions in order to obtain closed form expressions for added mass and radiation damping coefficients, along with the excitation force and torque. These formulations were derived and reported in a previous publication by the authors. While analytical predictions of the foundation loads agree very well with experiments, large discrepancies are seen in the pitch response close to resonance. These differences are analyzed by conducting a sensitivity study, in which system parameters, including damping and added mass values, are varied. The likely contributors to the differences between predictions and experiments are attributed to tank reflections, standing waves that can occur in long, narrow wave tanks, as well as the thin plate assumption employed in the analytical approach.
Stability of Concrete Mattresses
Authors: O’Brien Dermot , Draper Scott , An Hongwei
Published: September 2023

Concrete mattresses are widely used in the offshore industry for a variety of purposes, including to stabilise pipelines, flowlines and umbilicals, provide supports for span correction or crossings over other services and for scour mitigation.

Despite their widespread use, the stability of mattresses under hydrodynamic loading is not very well understood, an issue which is particularly apparent when the purpose of employing mattresses is to provide secondary stabilisation for a pipeline, flowline or umbilical against hydrodynamic loading. The complexity of the mattress shape does not easily lend itself to analytical solutions based on data presented in existing codes and papers, with the result that a conservative analysis of mattress stability is regularly adopted in project environments. Where the project requirement is for a small number of mattresses, this is not a significant issue, however where large numbers of mattresses are required, such conservative approaches can result in unnecessary project costs.

This paper presents the outcomes from two programs of physical model testing of mattresses specifically aimed at improving understanding of mattress stability under hydrodynamic loading, and the peak resistance that mattresses can provide to prevent flowline lateral movement when both the mattress and flowline are under hydrodynamic loading. While the physical model testing programs performed were tailored to specific project requirements, the testing results and means of application for those projects provide valuable insights to mattress stability under hydrodynamic loading, and a pathway to a less conservative approach to defining mattress requirements in such scenarios.
Challenges Associated With High Voltage Dynamic Inter Array Cables
Authors: Dobson Alan
Published: September 2023

Dynamic helical cables and umbilicals have been operating in a range of offshore environments for the past 35 years in support of Oil & Gas developments and from a range of hosts in a range of dynamic environments globally. With the advent of offshore wind power generation and more recently, the piloting of floating offshore wind power generation, the reliability of power cables is both a concern and a focus area for developers and operators as well as a research area for academia. Knowledge and lessons learnt from the Oil and Gas domain can be applied to the offshore floating wind domain but with some caveats. The paper will provide an insight into these lessons learnt and highlight critical risks with some potential mitigations.

There will be a focus upon system reliability with various modes of failure and the failure mechanisms discussed, such as material fatigue, creep, hydrolysis and corrosion, from a component perspective. Structural failure is also evaluated through a system perspective linking failure mechanism with global response of the riser cable and material degradation and ageing. In particular the coupled effects of mechanical, thermal and electromagnetic loading will be presented together with the design challenges they pose for installation, static and dynamic operation of the system.
Doppler Shift Approximation for Predicting the Wave-Induced Response of Advancing Vessels in Following Waves
Authors: Mounet Raphaël E. G. , Nielsen Ulrik D. , Brodtkorb Astrid H.
Published: September 2023

Being able to predict wave-induced responses of a ship is essential for assessment of safety and energy efficiency. The classical seakeeping theory has established a linear relationship between the wave spectrum and the induced response spectrum. However, for a ship sailing with non-zero forward speed, the wave components excite the structure at the encounter frequency, differing from the intrinsic wave frequency. In following seas, the Doppler shift introduces complications in the theoretical transformation of spectra from intrinsic- to encounter-frequency domains, and vice versa, the latter resulting in non-unique solutions. The present study proposes to mathematically substitute this non-bijective mapping with a bijective function approximating the true formulation of the Doppler shift. A case study is considered, simulating the motions of a Panamax containership in waves, to assess the quality of the response estimates computed through the approximation approach. The results demonstrate the ability and practicality of the method in accurately deriving response spectra for a wide range of forward speeds and headings, also in conditions that involve following waves.
Multi-Particle Modelling of Compressive Ice Failure During Indentation by Rock Particles
Authors: Fitzpatrick Thomas , Taylor Rocky S. , Thijssen Jan
Published: September 2023

The indentation of rock particles into ice is an important aspect of understanding subsea interactions involving ice features. If rock particles are present at the interface between ice and an engineered structure, the question arises: will localization of contact by the rocks cause the ice to fail more easily, resulting in reduced ice pressures, or will rocks transmit high ice pressures through smaller contact areas between the rock and structure resulting in more intense contact stresses on the surface of the structure? This paper presents initial results from a series of tests investigating the indentation of multiple rock particles into an ice specimen, which builds on earlier ice indentation tests on single unconstrained rock particles. Observations from tests conducted using 170g samples of rocks ranging in size from 9.5mm–19.1mm for tests completed at an indentation rate of 0.5 mm/s for indentation depths of 5 mm and 7 mm are presented and discussed. In addition, preliminary results are presented from a Matlab model that has been developed based on the aggregation of independent, individual particle-ice interaction events to simulate multiple particle-ice interactions. A comparison of experimental and simulated results indicates good general agreement and supports the assumption of independent particle-ice indentation events for the interaction conditions considered.
Stress Intensity Factors and T-Stress Solutions for Mixed-Mode Compact-Tension-Shear (CTS) Specimens With Slanted Propagating Cracks
Authors: Jin Pengfei , Liu Zheng , Chen Xu , Wang Xin
Published: September 2023

More and more attention has been paid to the problems of fatigue fracture in mixed fracture modes, and researchers have developed a variety of laboratory specimen types. Among them, the Compact-Tension-Shear (CTS) specimen with its loading device has been widely used in mixed-mode I&II fatigue crack growth (FCG) experiments. In this paper, for CTS specimen with slanted propagating crack, the variation of stress field parameters including stress intensity factors (SIFs) and T-stresses were investigated through three-dimensional finite element (FE) analysis. The results show that the direction of crack initiation tends to make KII vanish and then the crack propagates in a mode I dominant manner even under mode II dominant loading angles. In addition, among the considered range of geometries, T11 is greatly influenced by the initial crack length ratio, the slanted propagating crack length ratio and the loading angle, but rarely by the specimen thickness ratio. However, T33 as an out-of-plane constraint parameter, is subject to the coupling effects of in-plane geometries, out-of-plane geometries and the mixed-mode loading. The conclusions obtained in the current work will provide usable constraint-related crack front stress field parameter solutions for the analysis of fatigue crack propagating behavior in mixed fracture mode.
Low and High Cycle Fatigue Performance Limits of Seamless and Seam-Welded Umbilical Super Duplex Stainless Steel Tubes
Authors: Raji Hauwa , Fletcher-Woods Jamie , Dobson Alan
Published: September 2023

Umbilicals provide the critical link between remote subsea wells and fixed or floating production systems, providing control, power and communication services. Super duplex stainless steel (SDSS) umbilicals, designed for both static and dynamic applications, are now the preferred solution in wellhead control systems for deep water projects. The performance of the steel tube umbilicals (STU) is governed by the low and high cycle fatigue resistance of the seamless or seam-welded small bore SDSS tubes which act as the umbilicals tensile members.

This paper presents data on the low and high cycle fatigue performance of seamless and seam-welded umbilical SDSS tubes. Axial high cycle fatigue test data from pre-strained samples is presented and compared with industry standard curves. In addition, the impact of increasing levels of plastic strain cycling on the material integrity and fatigue performance of steel tubes is presented with the aim of defining an acceptable level of plastic strain that is not detrimental to its integrity.
Severe hematotoxicity after CD19 CAR-T therapy is associated with suppressive immune dysregulation and limited CAR-T expansion
Authors: Rejeski Kai , Perez Ariel , Iacoboni Gloria , Blumenberg Viktoria , Bücklein Veit L. , Völkl Simon , Penack Olaf , Albanyan Omar , Stock Sophia , Müller Fabian , Karschnia Philipp , Petrera Agnese , Reid Kayla , Faramand Rawan , Davila Marco L. , Modi Karnav , Dean Erin A. , Bachmeier Christina , von Bergwelt-Baildon Michael , Locke Frederick L , Bethge Wolfgang , Bullinger Lars , Mackensen Andreas , Barba Pere , Jain Michael D. , Subklewe Marion
Published: September 2023

Prolonged cytopenias after chimeric antigen receptor (CAR) T cell therapy are a significant clinical problem and the underlying pathophysiology remains poorly understood. Here, we investigated how (CAR) T cell expansion dynamics and serum proteomics affect neutrophil recovery phenotypes after CD19-directed CAR T cell therapy. Survival favored patients with “intermittent” neutrophil recovery (e.g., recurrent neutrophil dips) compared to either “quick” or “aplastic” recovery. While intermittent patients displayed increased CAR T cell expansion, aplastic patients exhibited an unfavorable relationship between expansion and tumor burden. Proteomics of patient serum collected at baseline and in the first month after CAR-T therapy revealed higher markers of endothelial dysfunction, inflammatory cytokines, macrophage activation, and T cell suppression in the aplastic phenotype group. Prolonged neutrophil aplasia thus occurs in patients with systemic immune dysregulation at baseline with subsequently impaired CAR-T expansion and myeloid-related inflammatory changes. The association between neutrophil recovery and survival outcomes highlights critical interactions between host hematopoiesis and the immune state stimulated by CAR-T infusion.
Selective and deceptive citation in the construction of dueling consensuses
Authors: Beers Andrew , Nguyễn Sarah , Starbird Kate , West Jevin D. , Spiro Emma S.
Published: September 2023

The COVID-19 pandemic provides a unique opportunity to study science communication and, in particular, the transmission of consensus. In this study, we show how “science communicators,” writ large to include both mainstream science journalists and practiced conspiracy theorists, transform scientific evidence into two dueling consensuses using the effectiveness of masks as a case study. We do this by compiling one of the largest, hand-coded citation datasets of cross-medium science communication, derived from 5 million Twitter posts of people discussing masks. We find that science communicators selectively uplift certain published works while denigrating others to create bodies of evidence that support and oppose masks, respectively. Anti-mask communicators in particular often use selective and deceptive quotation of scientific work and criticize opposing science more than pro-mask communicators. Our findings have implications for scientists, science communicators, and scientific publishers, whose systems of sharing (and correcting) knowledge are highly vulnerable to what we term adversarial science communication.
Temporal landscape of mitochondrial proteostasis governed by the UPR
mt
Authors: Uoselis Louise , Lindblom Runa , Lam Wai Kit , Küng Catharina J. , Skulsuppaisarn Marvin , Khuu Grace , Nguyen Thanh N. , Rudler Danielle L. , Filipovska Aleksandra , Schittenhelm Ralf B. , Lazarou Michael
Published: September 2023

Breakdown of mitochondrial proteostasis activates quality control pathways including the mitochondrial unfolded protein response (UPR
mt
) and PINK1/Parkin mitophagy. However, beyond the up-regulation of chaperones and proteases, we have a limited understanding of how the UPR
mt
remodels and restores damaged mitochondrial proteomes. Here, we have developed a functional proteomics framework, termed MitoPQ (Mitochondrial Proteostasis Quantification), to dissect the UPR
mt
’s role in maintaining proteostasis during stress. We find essential roles for the UPR
mt
in both protecting and repairing proteostasis, with oxidative phosphorylation metabolism being a central target of the UPR
mt
. Transcriptome analyses together with MitoPQ reveal that UPR
mt
transcription factors drive independent signaling arms that act in concert to maintain proteostasis. Unidirectional interplay between the UPR
mt
and PINK1/Parkin mitophagy was found to promote oxidative phosphorylation recovery when the UPR
mt
failed. Collectively, this study defines the network of proteostasis mediated by the UPR
mt
and highlights the value of functional proteomics in decoding stressed proteomes.
Autonomous DNA molecular motor tailor-designed to navigate DNA origami surface for fast complex motion and advanced nanorobotics
Authors: Siti Winna , Too Hon Lin , Anderson Tommy , Liu Xiao Rui , Loh Iong Ying , Wang Zhisong
Published: September 2023

Nanorobots powered by designed DNA molecular motors on DNA origami platforms are vigorously pursued but still short of fully autonomous and sustainable operation, as the reported systems rely on manually operated or autonomous but bridge-burning molecular motors. Expanding DNA nanorobotics requires origami-based autonomous non–bridge-burning motors, but such advanced artificial molecular motors are rare, and their integration with DNA origami remains a challenge. Here, we report an autonomous non–bridge-burning DNA motor tailor-designed for a triangle DNA origami substrate. This is a translational bipedal molecular motor but demonstrates effective translocation on both straight and curved segments of a self-closed circular track on the origami, including sharp ~90° turns by a single hand-over-hand step. The motor is highly directional and attains a record-high speed among the autonomous artificial molecular motors reported to date. The resultant DNA motor-origami system, with its complex translational-rotational motion and big nanorobotic capacity, potentially offers a self-contained “seed” nanorobotic platform to automate or scale up many applications.
Age-dependent acquisition of pathogenicity by SARS-CoV-2 Omicron BA.5
Authors: Imbiakha Brian , Ezzatpour Shahrzad , Buchholz David W. , Sahler Julie , Ye Chengjin , Olarte-Castillo Ximena A. , Zou Anna , Kwas Cole , O’Hare Katelyn , Choi Annette , Adeleke Richard Ayomide , Khomandiak Solomiia , Goodman Laura , Jager Mason C. , Whittaker Gary R. , Martinez-Sobrido Luis , August Avery , Aguilar Hector C.
Published: September 2023

Pathology studies of SARS-CoV-2 Omicron variants of concern (VOC) are challenged by the lack of pathogenic animal models. While Omicron BA.1 and BA.2 replicate in K18-hACE2 transgenic mice, they cause minimal to negligible morbidity and mortality, and less is known about more recent Omicron VOC. Here, we show that in contrast to Omicron BA.1, BA.5-infected mice exhibited high levels of morbidity and mortality, correlating with higher early viral loads. Neither Omicron BA.1 nor BA.5 replicated in brains, unlike most prior VOC. Only Omicron BA.5–infected mice exhibited substantial weight loss, high pathology scores in lungs, and high levels of inflammatory cells and cytokines in bronchoalveolar lavage fluid, and 5- to 8-month-old mice exhibited 100% fatality. These results identify a rodent model for pathogenesis or antiviral countermeasure studies for circulating SARS-CoV-2 Omicron BA.5. Further, differences in morbidity and mortality between Omicron BA.1 and BA.5 provide a model for understanding viral determinants of pathogenicity.
Iron ions regulate antifungal HSAF biosynthesis in
Lysobacter enzymogenes
by manipulating the DNA-binding affinity of the ferric uptake regulator (Fur)
Authors: Tang Bao , Wang Bo , Xu Zhizhou , Hou Rouxian , Zhang Min , Chen Xian , Liu Youzhou , Liu Fengquan
Published: September 2023

Heat-stable antifungal factor (HSAF), produced by
Lysobacter enzymogenes
OH11, is regarded as a potential biological pesticide due to its broad-spectrum antifungal activity and novel mode of action. However, the current production of HSAF is low and cannot meet the requirements for large-scale production. Herein, we discovered that iron ions greatly promoted HSAF production, and the ferric uptake regulator (Fur) was involved in this regulatory process. Fur was also found to participate in the regulation of iron homeostasis in OH11 via the classic inhibition mechanism of
Holo
-Fur. Furthermore, Fur was collectively observed to directly bind to the promoter of the HSAF biosynthesis gene, and its DNA-binding affinity was attenuated by the addition of iron ions
in vitro
and
in vivo
. Its regulatory mechanism followed the uncommon inhibition mechanism of
Apo
-Fur. In summary, Fur exhibited a bidirectional regulatory mechanism in OH11. This study reveals a novel regulatory mechanism whereby Fur upregulates the biosynthesis of secondary metabolites. These findings contribute to the improvement of HSAF production and may guide its development into biological pesticides.

IMPORTANCE

HSAF possesses potent and broad antifungal activity with a novel mode of action. The HSAF yield is critical for fermentation production. In this study, iron ions were found to increase HSAF production, and the specific mechanism was elaborated. These results provide theoretical support for genetic transformation to improve HSAF yield, supporting its development into biological pesticides.
Supplemental Material: Petrogenesis of Paleocene–Eocene gabbros in the Gangdese belt: Geochemical tracking of transitioning from oceanic subduction to continental collision related magmatism in southern Tibet
Authors: Hu Zhaoping , Li Huan , et al.
Published: September 2023

Supplemental Tables S1–S6.
State-of-the-Art Approaches to Heterologous Expression of Bispecific Antibodies Targeting Solid Tumors
Authors: Misorin Aleksei K. , Chernyshova Darya O. , Karbyshev Mikhail S.
Published: September 2023

Bispecific antibodies (bsAbs) are some of the most promising biotherapeutics due to the versatility provided by their structure and functional features. bsAbs simultaneously bind two antigens or two epitopes on the same antigen. Moreover, they are capable of directing immune effector cells to cancer cells and delivering various compounds (radionuclides, toxins, and immunologic agents) to the target cells, thus offering a broad spectrum of clinical applications. Current review is focused on the technologies used in bsAb engineering, current progress and prospects of these antibodies, and selection of various heterologous expression systems for bsAb production. We also discuss the platforms development of bsAbs for the therapy of solid tumors.
Early treatment of type II SMA slows rate of progression of scoliosis
Authors: Coratti Giorgia , Lenkowicz Jacopo , Pera Maria Carmela , D'Amico Adele , Bruno Claudio , Gullì Consolato , Brolatti Noemi , Pedemonte Marina , Antonaci Laura , Ricci Martina , Capasso Anna , Cicala Gianpaolo , Cutrona Costanza , de Sanctis Roberto , Carnicella Sara , Forcina Nicola , Cateruccia Michela , Damasio Maria Beatrice , Labianca Luca , Manfroni Francesca , Leone Antonio , Bertini Enrico , Pane Marika , Patarnello Stefano , Valentini Vincenzo , Mercuri Eugenio
Published: September 2023

Background

Type II spinal muscular atrophy (SMA) often leads to scoliosis in up to 90% of cases. While pharmacological treatments have shown improvements in motor function, their impact on scoliosis progression remains unclear. This study aims to evaluate potential differences in scoliosis progression between treated and untreated SMA II patients.

Methods

Treatment effect on Cobb’s angle annual changes and on reaching a 50° Cobb angle was analysed in treated and untreated type II SMA patients with a minimum 1.5-year follow-up. A sliding cut-off approach identified the optimal treatment subpopulation based on age, Cobb angle and Hammersmith Functional Motor Scale Expanded at the initial visit. Mann-Whitney U-test assessed statistical significance.

Results

There were no significant differences in baseline characteristics between the untreated (n=46) and treated (n=39) populations. The mean Cobb angle variation did not significantly differ between the two groups (p=0.4). Optimal cut-off values for a better outcome were found to be having a Cobb angle <26° or an age <4.5 years. When using optimal cut-off, the treated group showed a lower mean Cobb variation compared with the untreated group (5.61 (SD 4.72) degrees/year vs 10.05 (SD 6.38) degrees/year; p=0.01). Cox-regression analysis indicated a protective treatment effect in reaching a 50° Cobb angle, significant in patients <4.5 years old (p=0.016).

Conclusion

This study highlights that pharmacological treatment, if initiated early, may slow down the progression of scoliosis in type II SMA patients. Larger studies are warranted to further investigate the effectiveness of individual pharmacological treatment on scoliosis progression in this patient population.
Effectiveness of psychological skills training for police personnel: a meta-analysis
Authors: Lu Yi-Fang , Petersen Kevin
Published: September 2023

There has been an increasing interest in primary prevention programmes developed to improve police officers’ mental health. This meta-analysis synthesised the existing findings on psychological skills training for police personnel including resilience training and mindfulness-based training. Particularly, this study systematically assessed the effectiveness of training programmes on mental health outcomes including resilience, depression, anxiety and perceived stress. A comprehensive search of EBSCO, ProQuest and Web of Science was conducted for studies written in English from 1999 to 2022. Two independent researchers screened 5604 studies. Eligible studies are intervention studies with controlled trials that involved training programmes to improve participants’ mental health and reported at least one of the following outcomes: resilience, depression, anxiety and perceived stress. The meta-analysis estimated standardised mean differences (SMDs) for each of the four outcomes. A total of 12 studies, involving 2298 police personnel from 8 countries, met the criteria for inclusion and quality assessment. The training programmes of the eligible studies varied in training approaches, duration, total sessions and follow-up periods. The results suggest that training programmes have a statistically significant moderate effect on depression (SMD=−0.47, 95% CI=−0.73 to −0.22) and anxiety (SMD=−0.40, 95% CI=−0.73 to −0.06), while the effects on resilience (SMD=1.03, 95% CI=−0.36 to 2.41) and perceived stress (SMD=−1.03, 95% CI=−2.15 to 0.08) are not statistically significant. This study highlights the role of primary prevention approaches in supporting officers’ mental health by showing that training programmes are effective in mitigating the risk of depression and anxiety.
Use of non-surgical treatments on the journey to knee replacement in patients with knee osteoarthritis: a 10-year population-based case–control study
Authors: Dell'Isola Andrea , Hellberg Clara , Turkiewicz Aleksandra , Appleyard Tom , Yu Dahai , Thomas Geraint , Peat George , Englund Martin
Published: September 2023

Aim

To investigate temporal trends in primary care visits, physiotherapy visits, dispensed non-steroidal anti-inflammatory drugs (NSAIDs) and opioids in knee osteoarthritis (OA) patients who have and have not undergone knee replacement.

Methods

We analysed 5665 OA patients from the Skåne Healthcare Register, Sweden, who underwent knee replacement between 2015 and 2019. Controls were OA patients without knee replacement, matched 1:1 by sex, age, time and healthcare level of initial OA diagnosis, and assigned a pseudo-index date corresponding to their case’s knee replacement date. Annual prevalence and prevalence ratio of primary care and physiotherapy visits, dispensed NSAIDs and opioids (all for any cause) in the 10 years before knee replacement were estimated using Poisson regression.

Results

The annual prevalence of all-cause primary care visits, physiotherapy visits and opioid use was similar between cases and controls until 3 years before the index date when it started to increase among the cases. The year before the index date, the prevalence ratio (cases vs controls) for physiotherapy use was 1.8 (95% CI 1.7, 1.8), while for opioid use 1.6 (1.5, 1.7). NSAID use was consistently higher among cases, even 10 years before the index date when the prevalence ratio versus controls was 1.3 (1.2, 1.3), increasing to 1.8 (1.7, 1.9) in the year preceding the index date.

Conclusions

Management of OA patients who have and have not undergone knee replacement appears largely similar except for higher use of NSAIDs in knee replacement cases. Symptomatic treatments start to increase a few years before the surgery in knee replacement cases.
Structure and genetic diversity of Canadian Maritimes wild hops
Authors: Somalraju Ashok , Soto-Cerda Braulio , Ghose Kaushik , McCallum Jason , Knox Ron , Fofana Bourlaye
Published: September 2023

Studies on the northeastern American native hops ( Humulus lupulus ssp . lupuloides) from the Canadian Maritimes are scarce. This study aimed to evaluate the genetic structure and diversity among 25 wild-collected hops from three Canadian Maritime provinces using microsatellite (simple sequence repeat (SSR)) markers. Based on 43 SSR markers, four distinct subgroups were found, with a low molecular variance (19%) between subgroups and a high variance (81%) within subgroups. The Nei’s unbiased genetic distance between clusters ranged from 0.01 to 0.08, the genetic distance between clusters 2 and 3 being the farthest and that between clusters 1 and 2 the closest. Cluster 2 captured the highest overall diversity. A total of 18 SSR markers clearly discriminated hop clones by detecting putative subspecies-specific haplotypes, differentiating clones of native-wild H. lupulus ssp . lupuloides from the naturalized old and modern hop cultivars. Seven of the 18 SSR markers also differentiated two clones from the same site from one another. The study is the first, using molecular markers, to identify SSR markers with potential for intellectual property protection in Canadian Maritimes hops. The SSR markers herein used can be prime tools for hop breeders and growers in the region.
Can the two-pole structure of the $$D_{0}^{*}(2300)$$ be understood from recent lattice data?
Authors: Asokan Anuvind , Tang Meng-Na , Guo Feng-Kun , Hanhart Christoph , Kamiya Yuki , Meißner Ulf-G.
Published: September 2023

It was demonstrated in a series of papers employing unitarized chiral perturbation theory that the phenomenology of the scalar open-charm state, the $$D_0^*(2300)$$

D
0
∗

(
2300
)

, can be understood as the interplay of two poles, corresponding to two scalar-isospin doublet states with different SU(3) flavor content. Within this formalism the lightest open charm positive parity states emerge as being dynamically generated from the scattering of the Goldstone-boson octet off D mesons, a picture that at the same time solves various problems that the experimental observations posed. However, in recent lattice studies of $$D\pi $$

D
π

scattering at different pion masses only one pole was reported in the $$D_0^*$$

D
0
∗

channel, while it was not possible to extract reliable parameters of a second pole from the lattice data. In this paper we demonstrate how this seeming contradiction can be understood and that imposing SU(3) constraints on the fitting amplitudes allows one to extract information on the second pole from the lattice data with minimal bias. The results may also be regarded as a showcase how approximate symmetries can be imposed in the K-matrix formalism to reduce the number of parameters.
Elsa: enhanced latent spaces for improved collider simulations
Authors: Nachman Benjamin , Winterhalder Ramon
Published: September 2023

Simulations play a key role for inference in collider physics. We explore various approaches for enhancing the precision of simulations using machine learning, including interventions at the end of the simulation chain (reweighting), at the beginning of the simulation chain (pre-processing), and connections between the end and beginning (latent space refinement). To clearly illustrate our approaches, we use W + jets matrix element surrogate simulations based on normalizing flows as a prototypical example. First, weights in the data space are derived using machine learning classifiers. Then, we pull back the data-space weights to the latent space to produce unweighted examples and employ the Latent Space Refinement (Laser) protocol using Hamiltonian Monte Carlo. An alternative approach is an augmented normalizing flow, which allows for different dimensions in the latent and target spaces. These methods are studied for various pre-processing strategies, including a new and general method for massive particles at hadron colliders that is a tweak on the widely-used RamboOnDiet mapping. We find that modified simulations can achieve sub-percent precision across a wide range of phase space.
Effects of Dzyaloshinskii–Moriya interactions on dipole-exchange spin waves in finite-length ferromagnetic chains
Authors: Hussain Bushra , Cottam Michael G.
Published: September 2023

A spin-wave theory that includes the antisymmetric Dzyaloshinskii–Moriya exchange interactions and long-range dipole–dipole interactions, in addition to the Heisenberg bilinear exchange and the applied magnetic field, is presented for finite-length ferromagnetic spin chains. It is found that three different physical situations arise, depending on the direction chosen in this geometry for the axial vector of the Dzyaloshinskii–Moriya interactions. In some cases this leads to a tilting of the equilibrium orientations near the ends of the chain due to interfacial effects and with consequential effects on the spectrum of discrete dipole-exchange spin waves. When variations are introduced for the dominant bilinear exchange interactions at the ends of the spin chain, it is shown that localized spin waves with spatial decay characteristics may occur.
MIXED MULTIFRACTAL SPECTRA OF HOMOGENEOUS MORAN MEASURES
Authors: HATTAB JIHED , SELMI BILEL , VERMA SAURABH
Published: September 2023

There are only two kinds of measures in which the mixed multifractal formalism applies, which are self-similar and self-conformal measures. This paper studies the validity and non-validity of the mixed multifractal formalism of other kinds of measures, called irregular/homogeneous Moran measures.
A ONE-DIMENSIONAL CONTINUOUS FUNCTION WITH UNBOUNDED VARIATION
Authors: YANG DONG , YUAN XIA , ZHANG KANG , WU SHIWEI , ZHAO CHUNXIA
Published: September 2023

In this paper, we consider a function with only one unbounded variation point and study the box dimension of its graph. We prove that the function is continuous and differentiable on a certain interval. Moreover, we show that the function is of unbounded variation on the domain of definition. Using our techniques, we also estimate the box dimension of the graph of the function.