bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development of SGT-A35 GT61 (39 MW) for Oil and Gas Applications
Authors: Thirumurthy Deepak , Perez Vincent , Wong Mew Wah Didier , Scudamore Mark 
Published: August 2024

Abstract
The SGT-A35 (previously known as Industrial RB211) aeroderivative gas turbine is derived from the Rolls-Royce RB211 aviation gas turbine and it has a fleet size of more than 800 units. It is a known reference in the oil and gas market for both offshore and onshore application with more than 46 million hours of operating experience. Since its entry into service in 1974, this gas turbine has gone through continuous improvement with advanced technologies for increased power output, cycle efficiency, reliability, and availability. The SGT-A35 GT61 is the current fourth-generation gas turbine which was introduced in 2001 and provides 34 MW.
The new fifth generation SGT-A35 GT61 (39 MW) is the latest and most significant development in the Siemens Energy aeroderivative gas turbine product portfolio. The design changes were limited to cold section of the gas turbine. This includes addition of stage zero to the intermediate pressure compressor, newly designed variable inlet guide vane, variable stator vanes, and minor redesign to other compressor stages. These changes increased the flow capacity and greater than 10% increase in shaft power is achieved. No changes to the hot section has been implemented to maintain the industry class reliability and to keep the fleet experience relevant.
This paper provides the details on how the new fifth generation SGT-A35 variant was developed and verified. An extensive engine test program was completed at Siemens Energy facilities to verify all critical-to-quality attributes and to mitigate technical risks before the entry to service. In addition to the design details, results from the development test campaign are presented. The test exceeded the expectations and provided valuable data for further optimization of the product performance.
Effect of Geometry Modification of a Double Entrance Y-Duct Inlet on Aerodynamic Performance With High Speed Flow
Authors: Gilbart Ben , Rider Courtney , Asghar Asad , Allan William D. E. , Stowe Robert A. , Pimentel Rogerio 
Published: August 2024

Abstract
Certain aircraft configurations use embedded gas turbine engines that require offset inlets to direct oncoming air to the engine face. Y-duct inlets are commonly used, especially in military aviation, due to their versatility and aerodynamic performance. Work completed at the Royal Military College of Canada has investigated the performance of two Y-duct designs to study the effect of certain geometric parameters on duct performance. A baseline duct was created and its performance was evaluated at an entrance Mach number of Ma = 0.63. The baseline duct was originally designed for Ma = 0.80 entrance flow; however, the flow choked in the Y-duct at Ma = 0.63. A modified Y-duct was then created by reducing offset and bends in the baseline geometry to overcome the problem. Static and total pressure recovery were evaluated at Ma = 0.8 to determine the presence of secondary flows in the modified duct. This work aims to develop the understanding of relationships between geometric parameters and performance of Y-duct inlets.
Comparative Life Cycle Assessment of Waste Coal and Biomass/Torrefied Biomass Co-Fired Power Plant With Carbon Capture and Storage Technologies
Authors: Sarkar Surja , Bhoi Prakash 
Published: August 2024

Abstract
Climate change is currently one of the prominent worldwide issues that has garnered significant attention. The primary sources of fuel for generating utility-scale electricity in the US include coal, natural gas, petroleum, and other gases. Global warming arises from the extensive release of greenhouse gases, specifically CO2, from the burning of fossil fuels. Nonetheless, the rapid expansion of biomass-based heat and electricity generation is contributing significantly to the attainment of the goal of zero carbon emissions, mostly because of their reduced carbon footprint. In this study, the life cycle impact assessment (LCA) of the 100 MW subcritical pulverized coal-fired power plants that utilize anthracite waste coal and loblolly pine biomass/torrefied biomass as the power plant feedstocks have been assessed with and without the implementation of carbon capture and storage (CCS) technology considering the corresponding material, energy, and transportation inputs and outputs. The findings demonstrate that as the biomass fraction in the power plant feed increases, the global warming potential (GWP) decreases, and an addition of CCS further reduces GWP. Moreover, it is observed that the acidification potential, particulate matter formation potential, and ozone depletion potential typically exhibit a diminishing trend with the increment of the biomass/torrefied biomass ratio in co-fired power plants. However, the eutrophication potential and photochemical smog formation potential show an escalated value in waste coal and torrefied biomass co-firing cases. Nonetheless, the water consumption of waste coal and biomass/torrefied biomass co-fired power plants escalates as the ratio of biomass/torrefied biomass increases, and the integration of CCS further increases the water consumption potential.
Insight Into the Rotor Dynamics Consortium’s History, Vision, and Ongoing Technical Projects
Authors: Powell Don , Patel Hemant 
Published: August 2024

Abstract
The Engine-Aero industry has used MSC Nastran for propulsion loads and dynamics for more than 40 years. Over that timeframe, many collaborative efforts have taken place to position MSC Nastran to satisfy the structural dynamics analysis requirements when designing a new engine and installing it on an airplane. In the late 1990s, a NASA/Boeing/MSC Software (now part of Hexagon AB) rotor dynamic consortium was formed. This effort lasted for a decade (∼1998 to 2008) and resulted in numerous significant rotor dynamics simulation capability improvements driven by Boeing, the jet engine manufacturers and turbo-machinery companies. Now it’s 2023, fifteen years later, and the Engine-Aero industry again is expressing the need to push additional development into MSC Nastran’s rotor dynamic capabilities. This is supported by Boeing, jet engine OEMs, including General Electric, Safran Aircraft Engines, Pratt and Whitney, Rolls-Royce, and Honeywell. The Rotor Dynamics Consortium aims to define, drive, and standardize requirements to build models to address demanding rotor dynamics modeling and simulation needs. In this paper we will discuss what constitutes the consortium, the participating companies, subject matter, and the timeline to complete some of the ongoing initiatives. It will also include technical details about some of the ongoing activities (but is not excluded to): Advanced non-linear harmonic response; Support for 1D, axisymmetric and 3D Rotors; Synchronous analysis with multiple rotors; Consistent super elements and model reduction techniques; Internal rotor damping; and the solution procedure to best capture the effects of internal rotor damping for complex eigenvalue analysis (Campbell diagram) and frequency response analysis.
A Large Language Model Interface for Cycle Modeling
Authors: Roddy Reese , Replogle Cole , Connolly Brian 
Published: August 2024

Abstract
Large Language Models (LLMs) have demonstrated intelligent capabilities, but there has been limited research into their applicability to engineering applications. This work assesses the potential of LLMs, specifically OpenAI’s GPT-4, as an interface for the Numerical Propulsion System Simulation (NPSS). Training data and code were provided to the LLM in context, and it was able to process and understand basic engineering concepts related to NPSS. In most cases it was able to satisfactorily answer user queries and provide suggestions. Despite the evident capability of the model, it also exhibited several deficiencies including errors, oversights, and high operational costs. The most insidious problems occurred when the LLM answered confidently and incorrectly. As such, LLMs cannot yet be relied on for complex engineering work. Potential areas for further development and testing to mitigate these issues were explored. An analysis of LLM temperature variation for simple recall and reasoning tasks was conducted, showing good repeatability and reliability, albeit on a limited test set. Future work could explore the development of a standardized NPSS test suite for LLM performance evaluation. With improvements, LLMs could have transformative implications for future users of complex engineering software.
Hybrid RANS-LES Simulation of Rotor-Stator Interaction in a Compressor Stage Using Grid-Adaptive Simulation Method
Authors: Tang Yumeng , Wei Xindi , Liu Yangwei 
Published: August 2024

Abstract
Flows in compressors are extremely complex with various scales. Small-scale turbulence, middle-scale rotor-stator interaction, large-scale corner separation and tip leakage flow, should all be considered in the simulation of compressors. Recently, a new hybrid RANS-LES strategy that modifies the turbulent viscosity equation based on the Kolmogorov energy spectrum termed the grid-adaptive simulation (GAS) method, is proposed by our group to achieve high accuracy simulation using different grid resolutions. In this study, the GAS method with the SST turbulence model is employed to simulate the rotorstator interaction just with RANS-like grid resolution in a singlestage transonic compressor TUDa-GLR open test case. Compared with experiments and other simulation methods (including RANS and DDES methods), results show that the GAS method can significantly improve the prediction accuracy for stall margin and radial distribution of flow parameters. Then, the effect of rotor-stator interaction on the secondary flow structures is analyzed based on the unsteady flow field simulated by the GAS method. Results show that the incorrect prediction of rotor tip leakage vortex breakdown and the underestimation of mixing losses in the tip region of the rotor are blamed for the high prediction deviation of RANS. An intuitive total pressure fluctuation caused by wakes is observed in the stator inlet. The particle tracking shows that the wake from the suction surface of the rotor has a strong trend to transport into the tip region of the stator. Spectral proper orthogonal decomposition (SPOD) is also utilized. Unsteady temporal-spatial structures induced by local unsteadiness and rotor-stator interaction (RSI) are distinguished by SPOD, which includes the reverse flow in the tip region of the rotor and the pressure wave generated from RSI. SPOD also found the separation of the stator on the suction side exhibits an unsteady fluctuation with a frequency of 1.6 BPF.
The Effect of Ischemic Preconditioning on Tennis Exercise Performance and the Recovery Subsequent to a Simulated Tennis Match: A Randomized Controlled Trial
Authors: Xin Zekun , Shi Yuxuan , Wu Ying 
Published: August 2024

Purpose: The purpose of this study was to investigate the effects of acute ischemic preconditioning (IPC) on tennis skill and physical exercise performance, as well as to explore whether 7-day repeated IPC (RIPC) accelerated fatigue recovery after a simulated tennis match. Methods: Twenty-nine male tennis-specific current students were randomly allocated into 1 of 2 groups: SHAM (n = 14, 3 × 5 min at 20 mm Hg) and IPC (n = 15, 3 × 5 min at 220 mm Hg). Participants in both groups engaged in acute IPC and RIPC interventions. After the first acute IPC intervention, assessments were conducted to evaluate tennis-specific skills and overall physical exercise capacity. Following completion of chronic RIPC interventions, all participants competed in a simulated tennis match specifically designed to induce fatigue. To evaluate recovery from this induced fatigue, physical exercise capacity tests were conducted at 24 and 48 hours postmatch, allowing for an assessment of the participants’ recovery capabilities over time. Results: After the first acute intervention, notable differences were observed between the IPC and SHAM groups in their performance on the repeated-sprint ability test. Specifically, the total times recorded were significantly shorter in the IPC group compared with the SHAM group (IPC: 109.05 [2.70] vs SHAM: 114.57 [7.45] s, P = .012), and this trend was also reflected in their best times (IPC: 4.20 [0.18] s vs SHAM: 4.39 [0.30] s, P = .042), indicating an immediate benefit of the IPC intervention on sprint performance. After a 7-day RIPC intervention, significant changes were noted in the SHAM group’s performance metrics postmatch. There was an increase (P < .001) in fatigue index from 22% (8%) to 30% (9%) during repeated-sprint ability test and a decrease in serve speed from 120.2 (17.5) to 106.7 (13.0) km/h (P = .002) and knee peek torque from 196.0 (49.0) to 162.7 (39) N (extension, 60°/s, P < .001) in the SHAM group 24 hours postmatch, relative to the IPC group. Moreover, compared with the SHAM group, the IPC group showed a lower rate of perceived exertion during the match (P < .001) and a decrease in visual analog scale score (P = .026) 24 hours postmatch, suggesting enhanced recovery and reduced perception of pain relative to the SHAM group. Conclusion: IPC could serve as a strategy to generate an ergogenic effect and recovery during training and competition.
Identification of novel and potent inhibitors of SARS-CoV-2 main protease from DNA-encoded chemical libraries
Authors: Akaberi Dario , Pourghasemi Lati Monireh , Krambrich Janina , Berger Julia , Neilsen Grace , Strandback Emilia , Turunen S. Pauliina , Wannberg Johan , Gullberg Hjalmar , Moche Martin , Chinthakindi Praveen Kumar , Nyman Tomas , Sarafianos Stefan G. , Sandström Anja , Järhult Josef D. , Sandberg Kristian , Lundkvist Åke , Verho Oscar , Lennerstrand Johan 
Published: August 2024

ABSTRACT

In vitro
screening of large compound libraries with automated high-throughput screening is expensive and time-consuming and requires dedicated infrastructures. Conversely, the selection of DNA-encoded chemical libraries (DECLs) can be rapidly performed with routine equipment available in most laboratories. In this study, we identified novel inhibitors of SARS-CoV-2 main protease (M
pro
) through the affinity-based selection of the DELopen library (open access for academics), containing 4.2 billion compounds. The identified inhibitors were peptide-like compounds containing an N-terminal electrophilic group able to form a covalent bond with the nucleophilic Cys145 of M
pro
, as confirmed by x-ray crystallography. This DECL selection campaign enabled the discovery of the unoptimized compound SLL11 (IC
50
= 30 nM), proving that the rapid exploration of large chemical spaces enabled by DECL technology allows for the direct identification of potent inhibitors avoiding several rounds of iterative medicinal chemistry. As demonstrated further by x-ray crystallography, SLL11 was found to adopt a highly unique U-shaped binding conformation, which allows the N-terminal electrophilic group to loop back to the S1′ subsite while the C-terminal amino acid sits in the S1 subsite. MP1, a close analog of SLL11, showed antiviral activity against SARS-CoV-2 in the low micromolar range when tested in Caco-2 and Calu-3 (EC
50
= 2.3 µM) cell lines. As peptide-like compounds can suffer from low cell permeability and metabolic stability, the cyclization of the compounds will be explored in the future to improve their antiviral activity.
N
-linked protein glycosylation in
Nanobdellati
(formerly DPANN) archaea and their hosts
Authors: Nakagawa Satoshi , Sakai Hiroyuki D. , Shimamura Shigeru , Takamatsu Yoshiki , Kato Shingo , Yagi Hirokazu , Yanaka Saeko , Yagi-Utsumi Maho , Kurosawa Norio , Ohkuma Moriya , Kato Koichi , Takai Ken 
Published: August 2024

ABSTRACT

Members of the kingdom
Nanobdellati
, previously known as DPANN archaea, are characterized by ultrasmall cell sizes and reduced genomes. They primarily thrive through ectosymbiotic interactions with specific hosts in diverse environments. Recent successful cultivations have emphasized the importance of adhesion to host cells for understanding the ecophysiology of
Nanobdellati
. Cell adhesion is often mediated by cell surface carbohydrates, and in archaea, this may be facilitated by the glycosylated S-layer protein that typically coats their cell surface. In this study, we conducted glycoproteomic analyses on two co-cultures of
Nanobdellati
with their host archaea, as well as on pure cultures of both host and non-host archaea.
Nanobdellati
exhibited various glycoproteins, including archaellins and hypothetical proteins, with glycans that were structurally distinct from those of their hosts. This indicated that
Nanobdellati
autonomously synthesize their glycans for protein modifications probably using host-derived substrates, despite the high energy cost. Glycan modifications on
Nanobdellati
proteins consistently occurred on asparagine residues within the N-X-S/T sequon, consistent with patterns observed across archaea, bacteria, and eukaryotes. In both host and non-host archaea, S-layer proteins were commonly modified with hexose,
N
-acetylhexosamine, and sulfonated deoxyhexose. However, the
N
-glycan structures of host archaea, characterized by distinct sugars such as deoxyhexose, nonulosonate sugar, and pentose at the nonreducing ends, were implicated in enabling
Nanobdellati
to differentiate between host and non-host cells. Interestingly, the specific sugar, xylose, was eliminated from the
N
-glycan in a host archaeon when co-cultured with
Nanobdella
. These findings enhance our understanding of the role of protein glycosylation in archaeal interactions.

IMPORTANCE

Nanobdellati
archaea, formerly known as DPANN, are phylogenetically diverse, widely distributed, and obligately ectosymbiotic. The molecular mechanisms by which
Nanobdellati
recognize and adhere to their specific hosts remain largely unexplored. Protein glycosylation, a fundamental biological mechanism observed across all domains of life, is often crucial for various cell–cell interactions. This study provides the first insights into the glycoproteome of
Nanobdellati
and their host and non-host archaea. We discovered that
Nanobdellati
autonomously synthesize glycans for protein modifications, probably utilizing substrates derived from their hosts. Additionally, we identified distinctive glycosylation patterns that suggest mechanisms through which
Nanobdellati
differentiate between host and non-host cells. This research significantly advances our understanding of the molecular basis of microbial interactions in extreme environments.
Ipsilateral or contralateral boosting of mice with mRNA vaccines confers equivalent immunity and protection against a SARS-CoV-2 Omicron strain
Authors: Ying Baoling , Liang Chieh-Yu , Desai Pritesh , Scheaffer Suzanne M. , Elbashir Sayda M. , Edwards Darin K. , Thackray Larissa B. , Diamond Michael S. 
Published: August 2024

ABSTRACT

Boosting with mRNA vaccines encoding variant-matched spike proteins has been implemented to mitigate their reduced efficacy against emerging SARS-CoV-2 variants. Nonetheless, in humans, it remains unclear whether boosting in the ipsilateral or contralateral arm with respect to the priming doses impacts immunity and protection. Here, we boosted K18-hACE2 mice with either monovalent mRNA-1273 (Wuhan-1 spike) or bivalent mRNA-1273.214 (Wuhan-1 + BA.1 spike) vaccine in the ipsilateral or contralateral leg after a two-dose priming series with mRNA-1273. Boosting in the ipsilateral or contralateral leg elicited equivalent levels of serum IgG and neutralizing antibody responses against Wuhan-1 and BA.1. While contralateral boosting with mRNA vaccines resulted in the expansion of spike-specific B and T cells beyond the ipsilateral draining lymph node (DLN) to the contralateral DLN, administration of a third mRNA vaccine dose at either site resulted in similar levels of antigen-specific germinal center B cells, plasmablasts/plasma cells, T follicular helper cells, and CD8
+
T cells in the DLNs and the spleen. Furthermore, ipsilateral and contralateral boosting with mRNA-1273 or mRNA-1273.214 vaccines conferred similar homologous or heterologous immune protection against SARS-CoV-2 BA.1 virus challenge with equivalent reductions in viral RNA and infectious virus in the nasal turbinates and lungs. Collectively, our data show limited differences in B and T cell immune responses after ipsilateral and contralateral site boosting by mRNA vaccines that do not substantively impact protection against an Omicron strain.

IMPORTANCE
Sequential boosting with mRNA vaccines has been an effective strategy to overcome waning immunity and neutralization escape by emerging SARS-CoV-2 variants. However, it remains unclear how the site of boosting relative to the primary vaccination series shapes optimal immune responses or breadth of protection against variants. In K18-hACE2 transgenic mice, we observed that intramuscular boosting with historical monovalent or variant-matched bivalent vaccines in the ipsilateral or contralateral limb elicited comparable levels of serum spike-specific antibody and antigen-specific B and T cell responses. Moreover, boosting on either side conferred equivalent protection against a SARS-CoV-2 Omicron challenge strain. Our data in mice suggest that the site of intramuscular boosting with an mRNA vaccine does not substantially impact immunity or protection against SARS-CoV-2 infection.
LKB1 suppresses KSHV reactivation and promotes primary effusion lymphoma progression
Authors: Li Guanya , Li Yinan , Tang Xinyu , Wang Lijie , Yue Shusheng , He Shanping , Li Tingting 
Published: August 2024

ABSTRACT

Viruses normally reprogram the host cell metabolic pathways as well as metabolic sensors to facilitate their persistence. The serine-threonine liver kinase B1 (LKB1) is a master upstream kinase of 5′-AMP-activated protein kinase (AMPK) that senses the energy status and therefore regulates the intracellular metabolic homeostasis. Previous studies showed that AMPK restricts Kaposi’s sarcoma-associated herpesvirus (KSHV) lytic replication in endothelial cells during primary infection and promotes primary effusion lymphoma (PEL) cell survival. However, the role of LKB1 in KSHV lytic reactivation and KSHV-associated malignancies is unclear. In this study, we found that LKB1 is phosphorylated or activated in KSHV-positive PEL cells. Mechanistically, KSHV-encoded vCyclin mediated LKB1 activation in PEL cells, as vCyclin knockout ablated, while vCyclin overexpression enhanced LKB1 activation. Furthermore, knockdown of LKB1 inactivated AMPK and induced KSHV reactivation, as indicated by the increased expression of viral lytic genes and the increased virions in supernatants. Accordingly, AMPK inhibition by functional knockdown or a pharmacologic inhibitor, Compound C, promoted KSHV reactivation in PEL cells. Furthermore, inhibition of either LKB1 or AMPKα1 efficiently induced cell death by apoptosis of PEL cells both
in vitro
and
in vivo
. Together, these results identify LKB1 as a vulnerable target for PEL, which could be potentially exploited for treating other virus-associated diseases.

IMPORTANCE

Kaposi’s sarcoma-associated herpesvirus (KSHV) is an oncogenic virus associated with several human cancers, such as primary effusion lymphoma (PEL). Here, we showed that serine-threonine liver kinase B1 (LKB1), upstream of 5
'
AMP-activated protein kinase (AMPK), is activated by KSHV-encoded vCyclin and maintains KSHV latency in PEL cells. Inhibition of either LKB1 or AMPK enhances KSHV lytic replication from latency, which at least partially accounts for PEL cell death by apoptosis. Compound C, a potent AMPK inhibitor, induced KSHV reactivation and efficiently inhibited PEL progression
in vivo
. Thus, our work revealed that LKB1 is a potential therapeutic target for KSHV-associated cancers.