bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modeling, Simulation, and Kinematic Validation of Transfemoral Prosthetic Mechanism With Ankle Varus–Valgus Characteristic
Authors: Song Majun , Li Zhongyi , Zheng Hao , Chen Weihai , Guo Sheng , Niu Lianzheng 
Published: September 2024

Abstract
Inspired by the kinesiology of human bionic joints, a transfemoral prosthetic mechanism based on a functional structure of parallel mechanism is developed for the transfemoral amputees. The walking interactive simulation is implemented based on human-prosthesis modeling to verify the kinematics of the designed prosthetic mechanism, as well as to explore compatibility between the amputees and prosthesis. Then, simulation-based prosthetic optimization is performed to pursue an optimized human-prosthesis model with economic metabolic consumption while eliminating compatibility errors including the joints' misalignment error between the affected limb and healthy limb, and the assembly error between human and prosthesis, so that the potential physical health problems can be avoided efficiently. This method is valuable for the optimal design of interactive rehabilitation robots. Finally, a developed proportional-integral-derivative-based (PID-based) finite-state machine (FSM) strategy is used, and the kinematic validation is carried out. The results show that the designed prosthesis possesses ankle varus–valgus characteristic, and it has a high human-like motion accuracy due to the FSM control can track prosthetic motion in each gait event. What's more, the prosthetic optimization can be an efficient method to enhance the biomechanical performance of human-prosthetic model so that the amputees have a more natural and symmetry gait.
Design, Kinematics, and Deployment of a Continuum Underwater Vehicle-Manipulator System
Authors: Sitler Justin , Wang Long 
Published: September 2024

Abstract
Underwater vehicle-manipulator systems (UVMSs) are underwater robots equipped with one or more manipulators to perform intervention missions. This article provides the mechanical, electrical, and software design of a novel UVMS equipped with a continuum manipulator, referred to as a continuum-UVMS. A kinematic model for the continuum-UVMS is derived in order to build an algorithm to resolve the robot’s redundancy and generate joint space commands. Different methods to optimize the trajectory for specific tasks are proposed using both the weighted least norm solution and the gradient projection method. Kinematic simulation results are analyzed to assess the performance of the proposed algorithm. Finally, the continuum-UVMS is deployed in an experimental demonstration in which both teleoperation and autonomous control are tested for a given reference trajectory.
Influence of Dilution and Effusion Flows in Generating Variable Inlet Profiles for a High-Pressure Turbine
Authors: Schaeffer Chad B. , Barringer Michael D. , Lynch Stephen P. , Thole Karen A. 
Published: September 2024

AbstractThe elevated flow temperatures and pressures exiting gas turbine combustors affect the efficiency and durability of the high-pressure turbine stage. Understanding the effects that result from the upstream dilution and effusion flow interaction in creating the combustor exit profiles is important to advancing gas turbines. Understanding how common combustor features, such as dilution jets and effusion cooling, interact based on computational predictions guided the design of a non-reacting profile simulator capable of producing a wide range of non-uniform temperature profiles representative of those entering high-pressure turbines. The mechanical design of a new simulator device, which will be experimentally tested in the future, is presented in this paper along with computational predictions of flow and thermal fields. The simulator was designed for modular installation into the Steady Thermal Aero Research Turbine (START), which is a continuous-duration, steady-state turbine facility that houses a single-stage test turbine. Features of the simulator included interchangeable liner panels with multiple rows of dilution jets and wall effusion cooling to study various hole diameters and patterns. The dilution jets generate elevated turbulence intensities and tailor the temperature profiles in the radial and circumferential directions. The air mass flow distribution and source flow temperatures are independently controlled. To aid in the simulator design, computational fluid dynamics (CFD) simulations using Reynolds-averaged Navier–Stokes modeling were conducted with a two-level Design of Experiments (DOE) approach to determine a number of engine-representative target profiles with temperature shapes that are mid-radius peaked, outer-diameter peaked, inner-diameter peaked, and uniform. A sensitivity analysis of the CFD DOE results determined which factors significantly affected the profile shape so that the target profiles could be produced. The analysis indicated that the main contributor to the temperature profile shape at near-wall vane radial span locations of 0–15% and 85–100% was the injection temperature of the effusion flow. The main contributor at radial span locations of 15–40% and 60–85% was the injection temperature of the third-row dilution jets, and at the mid-radius location of 40–60% vane radial span, the main contributor was the diameter of the first-row dilution holes.
Observation of the Achilles Tendon and Gastrocnemius Muscle’s Passive Stiffness During an Incremental Running Protocol
Authors: Nguyen Anh Phong , Bosquet Laurent , Cugnet-Evans Laureen , Detrembleur Christine , Mahaudens Philippe 
Published: September 2024

Objective: Passive stiffness, a biomechanical parameter, has a potential influence on running economy, thus playing a pivotal role in performance. This study aimed to quantify passive stiffness of the Achilles tendon and gastrocnemius muscle using myotonometry throughout an incremental running protocol. Methods: Twenty-one male participants underwent a multistage incremental test (Bordeaux test) on a treadmill until exhaustion. Passive stiffness of the gastrocnemius muscle and Achilles tendon was measured using a MyotonPRO device. Measurements were taken before, during, and after the incremental test. Results: Our findings indicated that passive stiffness of the medial gastrocnemius decreased at rest between prerun and postrun assessments (−20.12 N·m−1, P = .012). Furthermore, during the test, stiffness increased at low intensity (at 50% of maximal aerobic speed: +104.8 N·m−1, P = .042), returning to baseline values as intensity increased. Conclusions: Throughout an incremental running protocol, both Achilles tendon and gastrocnemius muscle stiffness initially increased and then decreased with escalating percentages of maximal aerobic speed. A deeper understanding of stiffness in running can inform more effective recommendations for runners’ strengthening and training.
Novel humanized anti-PcrV monoclonal antibody COT-143 protects mice from lethal
Pseudomonas aeruginosa
infection via inhibition of toxin translocation by the type III secretion system
Authors: Numata Shunsuke , Hara Takafumi , Izawa Masaaki , Okuno Yosuke , Sato Yasuhiko , Yamane Shoji , Maki Hideki , Sato Takafumi , Yamano Yoshinori 
Published: September 2024

ABSTRACT

Treatment of
Pseudomonas aeruginosa
infection is challenging due to its intrinsic and acquired antibiotic resistance. As the number of current therapeutic options for
P. aeruginosa
infections is limited, developing novel treatments against the pathogen is an urgent clinical priority. The suppression of virulence of
P. aeruginosa
could be a new therapeutic option, and the type III secretion system (T3SS), which enables the bacteria to translocate various kinds of toxins into host cells and inhibits cellular functions, is considered as one possible target. In this report, we examined T3SS inhibition by COT-143/INFEX702, a humanized monoclonal antibody against PcrV, T3SS component, and present the crystal structure of the antibody-PcrV complex. COT-143 inhibited T3SS-dependent cytotoxicity and protected mice from the mortality caused by
P. aeruginosa
infection. The inhibition of cytotoxicity coincided with inhibition of translocon formation in a host cell membrane, which is necessary for T3SS intoxication. COT-143 protected murine neutrophils and facilitated phagocytosis of
P. aeruginosa
. These results suggest that COT-143 facilitates
P. aeruginosa
clearance by protecting neutrophil via inhibition of T3SS-dependent toxin translocation. This is the first report to show that an anti-PcrV antibody directly interferes with translocon formation to inhibit intoxication of host cells.
In vitro
antimalarial susceptibility profile of
Plasmodium falciparum
isolates in the BEI Resources repository
Authors: Ahmed Amel O. A. , Nkhoma Standwell C. , Zaman Sharmeen , Rashid Sujatha , Bradford Rebecca , Stedman Timothy T. , Molestina Robert E. 
Published: September 2024

ABSTRACT

BEI Resources, a National Institute of Allergy and Infectious Diseases-funded program managed by the American Type Culture Collection, serves researchers worldwide through the provision of a centralized repository for the acquisition, production, characterization, preservation, storage, and distribution of standardized biological resources targeting National Institutes of Health priority pathogens including bacteria, viruses, pathogenic fungi, and parasitic protozoa. These reference materials are critical for the development of diagnostics, vaccines, and therapeutics and are available to qualified registered investigators and institutions worldwide. Bioresources within BEI include well-characterized malaria isolates as part of the Malaria Research and Reference Reagent Resource Center (MR4). These isolates are critical for screening antimalarial compounds, conducting drug resistance studies, and for resistance surveillance and management. In our efforts to enhance the characterization of MR4
P. falciparum
isolates, we measured antimalarial susceptibility of >100 isolates against a panel of standard antimalarial compounds. Our results provide valuable information to assist current and prospective users of the BEI Resources repository in making data-driven requests of isolates to meet their research needs.
Insights into prokaryotic communities and their potential functions in biogeochemical cycles in cold seep
Authors: Quan Qiumei , Liu Jiaxing , Li Chaolun , Ke Zhixin , Tan Yehui 
Published: September 2024

ABSTRACT

Microorganisms are significant drivers of organic matter mineralization and are essential in marine biogeochemical cycles. However, the variations and influencing factors in prokaryotic communities from cold-seep sediments to the water column and the specific role of these microorganisms in biogeochemical cycles in the water column above cold seep remain unclear. Here, we investigated prokaryotic communities and their roles in nitrogen/sulfur cycling processes and conducted
in situ
dissolved organic matter (DOM) enrichment experiments to explore the effects of diverse sources of DOM on prokaryotic communities. Field investigations showed that the prokaryotic communities in the near-bottom water were more similar to those in the deep layer of the euphotic zone (44.60%) and at a depth of 400 m (50.89%) than those in the sediment (18.00%). DOM enrichment experiments revealed that adding dissolved organic nitrogen (DON) and phosphorus DOP caused a notable increase in the relative abundances of Rhodobacterales and Vibrionales, respectively. A remarkable increase was observed in the relative abundance of Alteromonadales and Pseudomonadales after the addition of dissolved organic sulfur (DOS). The metagenomic results revealed that Proteobacteria served as the keystone taxa in mediating the biogeochemical cycles of nitrogen, phosphorus, and sulfur in the Haima cold seep. This study highlights the responses of prokaryotes to DOM with different components and the microbially driven elemental cycles in cold seeps, providing a foundational reference for further studies on material energy metabolism and the coupled cycling of essential elements mediated by deep-sea microorganisms.

IMPORTANCE
Deep-sea cold seeps are among the most productive ecosystems, sustaining unique fauna and microbial communities through the release of methane and other hydrocarbons. Our study revealed that the influence of seepage fluid on the prokaryotic community in the water column is surprisingly limited, which challenges conventional views regarding the impact of seepage fluids. In addition, we identified that different DOM compositions play a crucial role in shaping the prokaryotic community composition, providing new insights into the factors driving microbial diversity in cold seeps. Furthermore, the study highlighted Proteobacteria as key and multifaceted drivers of biogeochemical cycles in cold seeps, emphasizing their significant contribution to complex interactions and processes. These findings offer a fresh perspective on the dynamics of cold-seep environments and their microbial communities, advancing our understanding of the biogeochemical functions in deep-sea environments.
Performance analysis of a high-frequency two-stage proportional valve piloted by two high-speed on/off valve arrays
Authors: Gao Qiang , Li Linfei , Zhu Yuchuan 
Published: September 2024

Two-stage proportional valves (TSPV) have been used extensively for electro-hydraulic control systems with large-flow applications. Due to the inherent characteristics of the pilot spool, such as hysteresis, motion quality, and dead zone, the dynamic performance of the traditional TSPV cannot be further improved. To solve this issue, this paper proposes a high-frequency two-stage proportional valve (HFTSPV) piloted by two high-speed on/off valve arrays, which integrates the advantages of dual nozzle flapper mechanism and parallel-connected valve technology. First, an entire mathematical model is established, in which some key parameters are estimated by experiments, such as the actual diameters and flow coefficients of orifices, and flow coefficient of pilot valve. Then, the influences of fixed orifices with different diameters on the dynamic characteristics of main spool are explored. Subsequently, the optimal diameter of fixed orifice is calculated theoretically by using the maximum pressure sensitivity and flow linearity, aiming to realize the high dynamic and small displacement fluctuation. Finally, step and sinusoidal tracking experiments show that the delay time of the HFTSPV is close to 3.3 ms, and the displacement fluctuation decreases with the increase of tracking frequency. Amplitude–frequency results indicate that −3 dB frequency of the HFTSPV reaches 16 Hz under ±50% full scale and 30 Hz under 0% –50% full scale.
Rota–Baxter operators and skew left brace structures over Heisenberg group
Authors: Rathee Nishant 
Published: September 2024

Rota–Baxter operators on groups have been recently defined in [L. Guo, H. Lang and Y. Sheng, Integration and geometrization of Rota–Baxter Lie algebras, Adv. Math. 387 (2021) 107834], and they share a close connection with skew braces, as demonstrated in [V. Bardakov and V. Gubarev, Rota–Baxter groups, skew left braces, and the Yang–Baxter equation, J. Algebra 587 (2022) 328–351]. In this paper, we classify all Rota–Baxter operators of weight 1 on the Heisenberg Lie algebra of dimension 3 up to the Jordan canonical form of a [Formula: see text] matrix block by automorphisms of the Heisenberg Lie algebra. Using the fact that the exponential map from the Heisenberg Lie algebra to the Heisenberg group is bijective, we induce these operators on the Heisenberg group. Finally, we enumerate all skew left brace structures on the Heisenberg group induced by these Rota–Baxter operators.
Quantifying vertical borehole heat exchanger sustainability from a geothermal resource perspective in the UK
Authors: Receveur Mylène , McDermott Christopher Ian , Fraser-Harris Andrew , Gilfillan Stuart , Watson Ian 
Published: September 2024

Low-temperature geothermal energy is viewed as a renewable resource that could contribute to the decarbonization of residential heating in the UK. Here, we constrain the geothermal potential of the shallow subsurface to provide the heating requirements of a typical single-family house via a vertical borehole heat exchanger (BHE), to provide a preliminary framework for the heat resource licensing of such systems. Through analytical and numerical models, we calculate the heat balance for a typical house with a garden located in a Carboniferous sedimentary basin, which represents a large proportion of the UK land mass and the regions where energy poverty is more common. Neglecting the heat recharge via groundwater flow, our results indicate that geothermal, solar heat flux and radiogenic heat production can only replenish up to 5% of the heat extracted annually by a 100 m-long BHE in heat extraction-only mode. The lack of natural recharge causes the continuous expansion of the thermal footprint at an average rate of 18 m
2
a
−1
over 30 years, considering a ground thermal conductivity of 2.2 W m
−1
°C
−1
, with the area cooled by 1°C extending beyond the current minimum BHE spacing guidelines of 6 m. In Scotland, reinjecting
c
. 35% of the yearly heat requirements, which could be accomplished through borehole thermal energy storage, is shown to safeguard against resource over-exploitation and interference risks between neighbouring users in the majority of the high-demand areas. In view of a large deployment of BHEs, it is crucial to incorporate such reinjection strategies into a regulatory framework to ensure a resilient and sustainable utilization of shallow geothermal resources.
Excess Mortality in Persons with Concurrent HIV and Cancer Diagnoses: A Retrospective Cohort Study
Authors: Lee Kamaria L. , Sarovar Varada , Lam Jennifer O. , Leyden Wendy A. , Alexeeff Stacey E. , Lea Alexandra N. , Hechter Rulin C. , Hu Haihong , Marcus Julia L. , Yuan Qing , Kramer Jennifer R. , Lin Lilie L. , Chiao Elizabeth Y. , Towner William J. , Horberg Michael A. , Silverberg Michael J. 
Published: September 2024

Abstract

Background:
With extended lifespans for people with human immunodeficiency virus (PWH), there is a corresponding increased burden of chronic illnesses, including cancer. Our objective was to estimate the excess mortality among PWH with cancer compared with people without HIV (PWoH), accounting for the higher background mortality in the general PWH population.

Methods:
We identified 39,000 PWH and 387,767 demographically matched PWoH in three integrated healthcare systems from 2000 to 2016. We estimated excess mortality among PWH with cancer, computed as the cancer mortality rate difference-in-difference comparing PWH and PWoH. We evaluated five cancer groups: any cancer; virus-, human papillomavirus–, and Epstein–Barr virus –related cancers; virus-unrelated cancers, and common individual cancers. We fitted a multivariable additive Poisson model to estimate excess mortality among PWH with cancer.

Results:
PWH with any cancer had excess mortality compared with PWoH [41.3/1,000 person-years (py), 95% confidence interval (CI), 34.0–48.7]. The highest excess mortality was observed for Epstein–Barr virus–related cancers (63.2/1,000 py, 95% CI, 47.8–78.7), lung cancer (147.7/1,000 py, 95% CI, 41.1–254.3), and non–Hodgkin lymphoma (70.5/1,000 py, 95% CI, 51.4–89.6). Excess mortality among PWH was attenuated from 2009 to 2016, and PWH with cancer had no excess mortality 5 years after diagnosis.

Conclusion:
PWH in care may have excess mortality from certain cancer types, although disparities may have attenuated over time and do not persist beyond 5 years after diagnosis.

Impact:
Findings may guide improved clinical practice and suggest further research is needed to investigate whether cancer treatment or other factors contribute to mortality disparities for PWH with cancer.
Epigenome Reprogramming Through H3K27 and H3K4 Trimethylation as a Resistance Mechanism to DNA Methylation Inhibition in BRAFV600E-Mutated Colorectal Cancer
Authors: Lee Hey Min , Saw Ajay Kumar , Morris Van K. , Napolitano Stefania , Bristow Christopher , Srinivasan Sanjana , Peoples Micheal , Sorokin Alexey , Kanikarla Marie Preeti , Schulz Jonathan , Singh Anand K. , Terranova Christopher , Coker Oluwadara , Jain Abhinav , Kopetz Scott , Rai Kunal 
Published: September 2024

Abstract

Purpose:
BRAFV600E-mutated colorectal cancer exhibits a strong correlation with DNA hypermethylation, suggesting that this subgroup of tumors presents unique epigenomic phenotypes. Nonetheless, 5-azacitidine, which inhibits DNA methyltransferase activity, is not efficacious in BRAFV600E colorectal cancer in vivo.

Experimental Design:
We randomized and treated mice implanted with patient-derived tumor xenografts harboring BRAFV600E mutation with control, 5-azacitidine, vemurafenib (BRAF inhibitor), or the combination. Comprehensive epigenomic profiling was conducted on control and 5-azacitidine–treated tumor samples, including DNA methylation, histone modifications, chromatin accessibility, and gene expression. Combinations of epigenetic agents were explored in preclinical BRAFV600E colorectal cancer models.

Results:
A profound reduction of DNA methylation levels upon 5-azacitidine treatment was confirmed, however, transcriptional repression was not relieved. This study unbiasedly explored the adaptive engagement of other epigenomic modifications upon 5-azacitidine treatment. A loss of histone acetylation and a gain of histone methylations, including H3K27 and H3K4 trimethylation, were observed around these hypomethylated regions, suggesting the involvement of polycomb repressive complex (PRC) activity around the genome with loss of DNA methylation, therefore maintaining the repression of key tumor-suppressor genes. Combined inhibition of PRC activity through EZH2 inhibition with 5-azacitidine treatment additively improved efficacies in BRAFV600E colorectal cancer cells.

Conclusions:
In conclusion, DNA hypomethylation by 5-azacitidine exhibits a close association with H3K27me3 and PRC activity in BRAFV600E colorectal cancer, and simultaneous blockade of DNA methyltransferase and EZH2 holds promise as a potential therapeutic strategy for patients with BRAFV600E-mutated colorectal cancer.