bluuebunny/crossref_metadata_2025 huggingface dataset:
TRANSONIC COMRPESSOR DARMSTADT – OPEN TEST CASE
Authors:   Technical University of Darmstadt Institute of Gas Turbines and Aerospace Propulsion, Klausmann Fabian , Franke Daniel ,   Technical University of Darmstadt Institute of Gas Turbines and Aerospace Propulsion, Foret Jonas ,   Technical University of Darmstadt Institute of Gas Turbines and Aerospace Propulsion, Schiffer Heinz-Peter ,   Technical University of Darmstadt Institute of Gas Turbines and Aerospace Propulsion
Published: October 2022

Designs for future aero engines aim for increased efficiency with reduced exhaust gas and noise emissions. To achieve these goals, comprehensive physical understanding and highly innovative solutions are necessary. Even though computational capabilities are rising, the required confidence level is restrained. To understand and validate theoretical and numerical models, extensive experiments at realistic operating conditions are crucial. The modular compressor at the Transonic Compressor Darmstadt test facility at Technical University of Darmstadt enables investigations of prototype BLISK rotors in single or 1.5-stage setups, operating at high-speed conditions. Extensive steady and time-resolving instrumentation is used to determine the compressor aerodynamics and performance as well as aeroelastics. To foster improvements in numerical modelling and predictability based on high quality experimental data, the TUDa- GLR-OpenStage test case is introduced. It comprises the entire single stage setup, including the BLISK rotor, a 3D-optimized stator as well as the annulus contour. The data set is supplemented with comprehensive measurement data at stage inlet and exit as well as running tip clearances. This paper describes the open test case, related geometries, measurement procedures and corresponding experimental results, including steady state performance and unsteady aerodynamics. Ultimately, it is aiming to provide a standard case for future development of numerical models and comparable validation.
EVALUATION OF DDES BASED ON SST K-ω MODEL WITH DIFFERENT SHIELDING FUNCTIONS FOR TIP LEAKAGE FLOW IN TURBOMACHINERY
Authors:   1. School of Energy and Power Engineering, Beihang University 2. National Key Laboratory of Science and Technology on Aero-Engine Aero- Thermodynamics, Beihang University, Wang Guangyu , Tang Yumeng ,   1. School of Energy and Power Engineering, Beihang University 2. National Key Laboratory of Science and Technology on Aero-Engine Aero- Thermodynamics, Beihang University, Gao Yanfei ,   1. School of Energy and Power Engineering, Beihang University 2. National Key Laboratory of Science and Technology on Aero-Engine Aero- Thermodynamics, Beihang University, Liu Yangwei ,   1. School of Energy and Power Engineering, Beihang University 2. National Key Laboratory of Science and Technology on Aero-Engine Aero- Thermodynamics, Beihang University
Published: October 2022

With the rapid development of computing power, hybrid RANS/LES is a new trend in engineering, which is more accurate than RANS when using a fairly refined mesh and at a lower cost than LES to achieve the same level of accuracy. As a widely used hybrid RANS/LES method, the delayed detached eddy simulation (DDES) is popular for treating premature activation of LES calculation within the boundary layer through introducing shielding function. However, it is still difficult to accurately predict the tip leakage flow (TLF) in turbomachinery. In the current study, the performance of DDES based on SST k-ω model with three different shielding functions are elaborately compared for the TLF in turbomachinery. The current research uses a flow model for the TLF in turbomachinery using a square duct with a longitudinal slit to reduce computational cost. Flow details, such as three-dimensional flow structures and the distribution of turbulent kinetic energy in different flow slices, are evaluated in comparison with LES results. Results show that DDESSST method with all three kinds of shielding functions offers less unsteady flow features in the leakage flow region and the 𝐹2 shielding function suppresses mostly in the small-scale turbulent structures of the TLF.
ASSESSMENT OF RANS AND SBES METHODS FOR THE PREDICTION OF CORNER SEPARATION IN AXIAL FLOW COMPRESSORS
Authors:   Aero Engine Academy of China, Sun Wei
Published: October 2022

Corner separation is a common three-dimensional (3D) separated flow presented at the junction of the blade suction surface and endwall within axial-flow compressors. One commonly used Reynolds-Averaged Navier-Stokes (RANS) turbulence model in turbomachinery Computational Fluid Dynamics (CFD) simulations, Menter's Shear Stress Transport (SST) model, usually struggles to predict corner separation and its impact on compressor performance with reasonable accuracy. To improve RANS modelling accuracy for corner separation, efforts have been focused on the modifications of SST model in order for more of the endwall flow physics to be captured, such as the increased turbulence non-equilibrium and anisotropy due to the generation of skew-induced streamwise vortices in the endwall secondary flow. In this paper, the effect of the non-equilibrium and anisotropic modifications on the prediction of corner separation is evaluated using the results of the SST model and its variants. A high-fidelity time-accurate turbulence statistics database constructed by a newly developed hybrid RANS-Large Eddy Simulation (RANS-LES) method, Stress-Blended Eddy Simulation (SBES), is then used to feedback on RANS modelling. The investigation of the scale resolved corner flow physics facilitates understanding the physical reasons underlying the increased modelling accuracy of corner separation, in the meantime it reveals the modelling deficiencies that still exist.
Unsteady Analysis with Throughflow Concept
Authors:   Tsinghua University, Mao Yinbo , Su Xinrong ,   Tsinghua University, Yuan Xin ,   Tsinghua University
Published: October 2022

This paper presents a thoroughly derived theory that incorporates unsteady formulations into standard throughflow methods such that certain transient characteristics can be captured by throughflow analysis. In analogy to the relation between conventional throughflow methods and the mixing plane concept, this paper proposed a novel approach of quantifying the unsteadiness by relating the throughflow method to the chorochronic interface. Maintaining the advantage of low computational cost inherited from throughflow methods, the new method has huge potentials in the unsteady design of turbomachineries.
Research on Optimal Design of Gas Turbine Blade Tip Cooling Based on Conjugate Heat Transfer Method
Authors:   Shanghai Electric Gas Turbine Co., Ltd., HE Lei , LI Yueru ,   Shanghai Electric Gas Turbine Co., Ltd., ZHAO Jinjie ,   Shanghai Electric Gas Turbine Co., Ltd., ZHAO Lianhui ,   Shanghai Electric Gas Turbine Co., Ltd., ZHU Xiaocheng ,   Shanghai Jiaotong University, DU Chaohui ,   Shanghai Jiaotong University
Published: October 2022

Complex flow and heat transfer in the tip area of the turbine blades, as well as insufficient cooling, make the tip area more likely to be exposed to high-temperature and high-speed gas , which may lead the high thermal load problem. In order to improve working conditions of turbine blades and cool the blade tip, this paper proposed two cooling optimal schemes for blade tip based on original model. The heat transfer and flow characteristics in the tip region are analyzed based on the conjugate heat transfer (CHT) method. It is found that detailed film cooling design can effectively reduce blade tip temperature, especially from leading edge to the mid-chord region on the blade tip. In order to reduce the temperature at the trailing edge, blade tip cooling design is upgraded by improving internal cooling channel based on the optimized film cooling design. Results show that the film cooling and internal cooling channel can protect the trailing edge obviously where the thermal loads are highest. Compared with the original model, the maximum wall temperature of the tip trailing edge is reduced by 24K.
VALIDATION AND VERIFICATION OF RANS SOLVERS FOR TUDA-GLR-OPENSTAGE TRANSONIC AXIAL COMPRESSOR
Authors:   School of Aeronautics and Astronautics, Shanghai Jiao Tong University, Zhu Mingmin , He Xiao ,   Department of Mechanical Engineering, Imperial College London, Klausmann Fabian ,   Institute of Gas Turbines and Aerospace Propulsion, Technische Universit ¨ at Darmstadt, Teng Jinfang ,   School of Aeronautics and Astronautics, Shanghai Jiao Tong University, Vahdati Mehdi ,   Department of Mechanical Engineering, Imperial College London
Published: October 2022

This paper presents a comprehensive validation and verification study of turbomachinery Reynolds-averaged Navier-Stokes flow solvers on the transonic axial compressor TUDa-GLR-OpenStage. Two commercial solvers namely Ansys CFX and Numeca FineTurbo are adopted to provide the benchmark solutions, which can be used for verification of other RANS solvers in the future. Based on these solvers, five sets of grids, three advection schemes (i.e., central difference and second-order upwind from Numeca and high resolution from Ansys), two turbulence models (i.e., Spalart-Allmaras and Menter k 􀀀 w Shear Stress Transport) and two rotorstator interface models (i.e., mixing plane and sliding plane) are investigated to quantify their effects on predicting the performance and the flow field of the compressor stage. Some geometric uncertainties and errors including the rotor running tip gap size, the stator hub cavity and the stage throat area change are also discussed. Results show that the choice of grid density and turbulence model is most sensitive to the prediction; the choice of rotor-stator interface model mainly affects the near-tip flow field, but the effect on the overall characteristics is relatively small; the choice of advection scheme has limited effect on the prediction when using a refined mesh. Based on a grid density and an advection scheme with a small discretization error, none of the turbulence models and the rotor-stator interface models can perfectly capture the overall characteristics at the peak-efficiency condition. Possible reasons for the difference between the simulations and the experiment are discussed. The grids and the major CFD results presented in this work are open-accessed to the community for further research. The results and discussions presented in this paper provide a useful reference for future practices of RANS simulations for compressors.
Quantification of Compressor Aerodynamic Performance Deviation due to Manufacturing Uncertainty Using the Adjoint Method
Authors:   School of Power and Energy, Northwestern Polytechnical University, Zhang Qian , Xu Shenren ,   School of Power and Energy, Northwestern Polytechnical University, Yu Xianjun ,   Research Institute of Aero-Engine, Beihang University, Liu Jiaxin ,   School of Energy and Power Engineering, Beihang University, Wang Dingxi ,   School of Power and Energy, Northwestern Polytechnical University, Huang Xiuquan ,   School of Power and Energy, Northwestern Polytechnical University
Published: October 2022

Efficient and accurate Uncertainly Quantification (UQ) is essential for robust design optimization and manufacturing tolerance control to limit performance deterioration and scattering of compressor blades. Built upon past work, the current study investigates the applicability of the newly proposed adjoint method based nonlinear model for accurate and efficient Uncertainly Quantification (UQ) of performance deviations of a transonic compressor blade due to geometric variability. To demonstrate the advantages of the adjoint method based nonlinear model, two other methods, namely, the adjoint method based linear model and the high-fidelity computational fluid dynamics method are used to produce reference results. To keep the computational cost tractable for the high-fidelity method, a section of a transonic compressor blade is taken as the test case. In order to draw a more general conclusion, UQ analyses are performed for three different performance metrics (mass flow rate, efficiency and pressure ratio) at two typical operating conditions (the design condition and a near-stall condition). The accuracy of UQ results by the adjoint method based nonlinear model and its cost time are compared with those of the other two methods.
A 2D AXISYMMETRIC APPROACH FOR LOW PRESSURE TURBINE TIP SEALING DESIGN
Authors:   AECC SAIC, YI Zhuqing , JIN Yuan ,   BSS-TurboTech Ltd, XU Wenqi ,   AECC HAPRI, JUNG Olivier ,   Safran China
Published: October 2022

Low pressure turbine tip sealing design plays a key role in the overall turbine aerodynamic design, since it is responsible for a majority of performance loss. Meanwhile, given the complexity of its geometrical features from labyrinth seal configuration as well as the corresponding CFD modeling, design of such component in the purpose of reducing turbine leakage flow necessitates specific expertise from human expert. In the present study, instead of performing expensive 3D RANS simulation based design optimization, we address the tip sealing design of a low pressure turbine stage via a 2D axisymmetric approach. We show at first the consistency between 2D axisymmetric RANS simulations and their 3D counterpart in terms of flow characteristics within sealing and leakage mass flow. The 2D axisymmetric sealing design, which is parametrized considering geometrical constraints regarding mechanical and manufacturing feasibility, is optimized via a classification based genetic optimizer. 3 designs are accordingly derived from the optimization process and analyzed via 3D CFD simulation with turbine main flow in a RANS context. The effectiveness of the 2D design optimization is demonstrated by 3D validation. Furthermore, the effect of the tip sealing design on the main flow behavior is revealed from 3D simulation results.
An investigation on AerofoilShaped Blade Profiles for Centrifugal Turbines
Authors:   AeroThermoMechanics Université Libre de Bruxelles, Yu Min Liu Yu Min Liu , Patrick Hendrick Patrick Hendrick ,   AeroThermoMechanics Université Libre de Bruxelles, ZhengPing Zou ZhengPing Zou ,   School of Energy & Power Engineering Beihang University, Frank Buysschaert Frank Buysschaert ,   Applied Mechanics & Energy Conversion Katholieke Universiteit Leuven
Published: October 2022

In the current design paradigm of centrifugal turbines, blading design has drawn on that of axial turbines. However, the adequacy of such design practice has not been verified. Hence, this paper explores the possibility of developing new guidelines that produce centrifugal bladings of higher performance with respect to those of axial architecture operating under same inlet condition, through highfidelity numerical optimization. Performance is assessed base on the total pressure loss, work output, diffusion factor and Mach number ratio. The first optimized design adopting the axial blade velocity triangle achieves even performance. Meanwhile other profiles reach better performance. Centrifugal profiles have to resort to higher turning to produce the same work output as the axial one and should be characterized by reduced curvature.
Influence of honeycomb structures on labyrinth seal aerodynamics
Authors: Oettinger Marcel , Kluge Tim , Seume Joerg
Published: October 2022

Shroud cavities in aero engines are typically formed by a labyrinth seal between the rotating turbine shroud and the stationary casing wall. To mitigate rub-in and reduce weight, the casing often features honeycomb structures above the rotor seal fins. In this paper, the aerodynamic performance of such honeycomb structures is experimentally investigated using a rotating test rig featuring both smooth and honeycomb-tapered casing walls.

Measurements show that the discharge coefficient decreases for the honeycomb configuration while losses and subsequent windage heating of the flow increase. A variation in rotational speed reveals additional sensitivities to the local flow field in the swirl chamber. Numerical simulations are conducted and validated using the experiments. A good agreement between the prediction and measurements of the jet via the evolution of pressure across the sealing fins is identified. In contrast, the prediction of losses and integral parameters reveals larger deficits.

Empirical correlations from available literature satisfactorily predict the leakage mass flow rate if rotation is low and if the casing is smooth. High rotation and the presence of honeycombs, however, prove challenging and reveal the potential for further improvements. We propose a simple a-posteriori correction that can capture the effect of honeycomb structures on seal discharge by accounting for changes in momentum and flow area.
ANALISIS KEMAMPUAN PEMECAHAN MASALAH MATERI PENYAJIAN DATA KELAS IX SMP SUNGAI RAYA
Authors: Meisy Meisy Sella Maria , Tri Aniah  , Siti Salamah
Published: October 2022

Penelitian ini memiliki tujuan untuk menganalisis kemampuan siswa kelas IX terhadap pemecahan masalah menggunakan materi penyajian data. Terdapat empat indikator kemampuan pemecahan masalah siswa adalah: memahami masalah, merencanakan masalah, melaksanakan rencana, dan memeriksa kembali. Sampel diambil dengan menggunakan teknik purposive sampling. Analisis deskriptif adalah jenis penelitian yang digunakan dengan metode kualitatif yang dilihat dari hasil tes siswa. Instrumen yang digunakan adalah sebuah tes kemampuan pemecahan masalah. Data analisis pengerjaan siswa dikategorikan ke lima level diataranya sangat kurang, kurang, cukup, baik, sangat baik. Hasil analsisi menunjukan kemampuan siswa dalam memecahkan masalah masih rendah. Untuk soal nomor satu dikategorikan cukup dan nomor dua dikategorikan kurang Kemampuan pemecahan masalah siswa terhambat oleh kurangnya pemahaman soal dan kurangnya ketelitian dalam membaca soal.
ETHNIC-MATH HOTS PADA KUE KERING HOMEMADE IEDUL FITRI 1443 HIJRIAH
Authors: Lenny Puspita Dewi  , Novia Dwi Rahmawati
Published: October 2022

Pengembangan soal Mathematics Higher Order Thinking Skill (HOTS) berbasis budaya dan kearifan lokal (ethnic-Math HOTS) untuk meningkatkan kemampuan pemecahan masalah dan penalaran siswa. Tujuan  penelitian ini adalah memberikan desain dan gambaran soal matematika HOTS pada kue kering homemade. Metode penelitian merupakan penelitian dan pengembangan (Research and Development) dengan menghasilkan produk berupa soal Mathematics Higer Order Thinking Skill (HOTS) berbasis budaya dan kearifan lokal pada kue kering (ethnic-Math HOTS) Model pengembangan yang diacu oleh peneliti adalah model pengembangan Analysis, Design, Development, Implementation and Evaluation (ADDIE) yang diadaptasi menjadi Analysis, Design, Development (ADD). Tahapan yang telah tim peneliti lakukan saat ini baru pada tahapan design artinya desain soal Mathematics Higer Order Thinking Skill (HOTS) berbasis budaya dan kearifan lokal pada kue kering (ethnic-MathHOTS) yang akan dibuat akan di konsultasikan kepada para pakar yang terdiri dari pakar assessment dan pakar materi.
Efektivitas Model Pembelajaran Blended Learning dengan Pendekatan STEM dalam Kemampuan Berpikir Kritis Siswa
Authors: Safianti Suhastantin , Shoffa Shoffan , Suprapti Endang
Published: October 2022

Penelitian ini bertujuan untuk menunjukkan efektivitas penerapan model pembelajaran blended learning dengan pendekatan STEM (Science, Technology, Engineering, and Mathematics) pada materi sistem persamaan linear dua variabel (SPLDV) kelas VIII-E SMP Negeri 18 Surabaya. Jenis penelitian yang digunakan adalah penelitian deskriptif kuantitatif. Instrumen yang digunakan adalah soal tes kemampuan berpikir kritis, lembar observasi aktivitas siswa, lembar observasi kemampuan guru dalam mengelola pembelajaran, dan angket respon siswa. Hasil penelitian menunjukkan bahwa model pembelajaran blended learning dengan pendekatan STEM (Science, Technology, Engineering, and Mathematics) pada kelas VIII-E SMP Negeri 18 Surabaya tidak efektif dikarenakan hasil belajar dalam kemampuan berpikir kritis siswa memperoleh hasil rata-rata N-Gain skor sebesar 0,28 dikategorikan rendah. Meskipun  ketiga aspek lainnya telah memenuhi kriteria efektif ditunjukkan dengan keefektifan aktivitas siswa pada seluruh pertemuan mendapatkan rata-rata 89,9% yang dikategorikan sangat kuat, keefektifan kemampuan guru rata-rata 98, 4% dengan kategori sangat baik, dan respon siswa terhadap pembelajaran menunjukkan respon sangat positif. Hal tersebut seharusnya mempengaruhi hasil belajar siswa tetapi pada kenyataannya tidak mempengaruhi, ini dikarenakan siswa kurang dapat mengenali dan merumuskan masalah, belum mampu menyelesaikan soal dengan benar menggunakan semua metode SPLDV (eliminasi, substitusi, dan campuran).

Keywords: Blended Learning, Efektivitas, Kemampuan Berpikir Kritis, Pendekatan STEM
The Dietary, Serum and Urine Analysis of Boron and Micronutrients in Postmenopausal Women
Authors: GULBAHAR Aysegul , ÇAKAL, PH.D. Gaye , DİNÇER CENGİZ Sevim , ÇAĞLAR Gamze Sinem
Published: October 2022

Objective: Boron is a nutritionally important trace element that interacts with other micronutrients. Boron plays a critical role in bone mineralization and metabolism. In the present study, the association between boron and micronutrients related to bone metabolism was analysed in postmenopausal women.

Methods: In a prospective cohort study in 40 postmenopausal women 24-hour urine and blood samples were collected for sodium, phosphorus, calcium, magnesium, and boron. Daily food consumption, bone mineral density, and Fracture risk assessment tool scores were recorded.

Results: The mean age was 53.2 ± 5.9 years. Dietary habits revealed insufficient dietary fiber and excessive dietary sodium. The serum and urine boron levels were 26.80 μg/L and 21.22 μg/day, respectively. Urine boron levels were lower in the osteoporosis group (p = 0.66). A negative correlation between urine Na and boron was detected (p < 0.001). Urinary Na and Ca are negatively correlated with Fracture risk assessment tool scores (p = 0.010, p = 0.019, respectively).

Conclusion: The low urinary boron levels in our participants might be due to increased Na excretion due to excessive consumption of Na. Therefore, consulting postmenopausal women about their dietary habits is of concern. Further understanding of the role of boron in bone metabolism will help to accomplish new treatment strategies for osteoporosis and standardization of boron supplementation.
Evaluation of D-Dimer and Neutrophil/Lymphocyte Ratios of COVID-19 Patients Whom Applied to Karapınar State Hospital
Authors: KADER Saadet , AKDAĞ Turan , SARIYILDIZ Levent , ÖZEL Zeynep
Published: October 2022

Objective: The epidemic which caused by the SARS-CoV-2 virus were defined as COVID-19) and declared as a global pandemic by the World Health Organization (WHO) on March, 2020. Nowadays, many biochemical parameters related to the diagnosis and prognosis of COVID-19 are being investigated. Therefore, we aimed to evaluate D-dimer and neutrophil/lymphocyte ratios (NLR) of COVID-19 patients whom applied to Karapınar State Hospital.

Methods: Patients which consisted of 2523, whom diagnosed with COVID-19 between 11 March 2019 and 29 July 2021 at Karapınar State Hospital were included in the study. Age, gender and social history of the patients were recorded. From the results, the relationships between D-dimer and hemogram were evaluated.

Results: There was a high correlation between the variables HCT and HGB, PLT and PCT, NEUT# and WBC, and MCH and MCV (r=0.981, r=0.944, r=0.923, r=0.925). In addition, there was a high correlation between RBC and HCT and between RBC and HGB variables (r=0.852, r=0.795). There was a moderate correlation between WBC and MO#, MCHC and MCH, PDW and MPV (r=0.562, r=0.639, r=0.64). All the relationships between these variables were positive, and the value of the correlated parameter increases linearly by unit. Also, the highest positive relationships were between HCT and HGB, PLT and PCT, NEUT# and WBC, MCH and MCV. Moreover, D-dimer and NLR were not correlated (r= – 0.015, p=0.49).

Conclusion: In the study, no correlation was observed between D-dimer and neutrophil/lymphocyte ratios of COVID-19 patients. So, more comprehensive and further studies are needed to clarify these results.
Does the Presence of Metabolic Syndrome Alter Serum Uric Acid Concentrations, Pain, and Well-Being in Patient with Chronic Musculoskeletal Pain?
Authors: TOPRAK ÇELENAY Şeyda , ÖZER KAYA Derya , ŞAŞ Senem
Published: October 2022

Objective: To compare serum uric acid concentrations, pain and well-being in patients having chronic musculoskeletal pain with and without MetS, and investigate cut-off values.

Methods: Patients having chronic musculoskeletal pain with (MetS group, n=48) and without MetS (control group, n=52) were included. The serum uric acid concentration, pain intensity, body composition, physical activity level, quality of life, and psychological status were evaluated by a uric acid blood test, Visual Analogue Scale, Bio-impedance Analyzer, International Physical Activity Questionnaire-7 (IPAQ-7), Nottingham Health Profile, and Hospital Anxiety and Depression Scale, respectively.

Results: Uric acid level, fat mass, waist/hip ratio were found higher in the MetS group in comparison to the control group (P
Connecting the dots: A practical evaluation of web-tools for describing protein dynamics as networks
Authors: Petrizzelli Francesco , Biagini Tommaso , Bianco Salvatore Daniele , Liorni Niccolò , Napoli Alessandro , Castellana Stefano , Mazza Tommaso
Published: October 2022

Protein Structure Networks (PSNs) are a well-known mathematical model for estimation and analysis of the three-dimensional protein structure. Investigating the topological architecture of PSNs may help identify the crucial amino acid residues for protein stability and protein-protein interactions, as well as deduce any possible mutational effects. But because proteins go through conformational changes to give rise to essential biological functions, this has to be done dynamically over time. The most effective method to describe protein dynamics is molecular dynamics simulation, with the most popular software programs for manipulating simulations to infer interaction networks being RING, MD-TASK, and NAPS. Here, we compare the computational approaches used by these three tools—all of which are accessible as web servers—to understand the pathogenicity of missense mutations and talk about their potential applications as well as their advantages and disadvantages.
Reconstruction and optimization of a Pseudomonas putida-Escherichia coli microbial consortium for mcl-PHA production from lignocellulosic biomass
Authors: Qin Ruolin , Zhu Yinzhuang , Ai Mingmei , Jia Xiaoqiang
Published: October 2022

The demand for non-petroleum-based, especially biodegradable plastics has been on the rise in the last decades. Medium-chain-length polyhydroxyalkanoate (mcl-PHA) is a biopolymer composed of 6–14 carbon atoms produced from renewable feedstocks and has become the focus of research. In recent years, researchers aimed to overcome the disadvantages of single strains, and artificial microbial consortia have been developed into efficient platforms. In this work, we reconstructed the previously developed microbial consortium composed of engineered Pseudomonas putida KT∆ABZF (p2-a-J) and Escherichia coli ∆4D (ACP-SCLAC). The maximum titer of mcl-PHA reached 3.98 g/L using 10 g/L glucose, 5 g/L octanoic acid as substrates by the engineered P. putida KT∆ABZF (p2-a-J). On the other hand, the maximum synthesis capacity of the engineered E. coli ∆4D (ACP-SCLAC) was enhanced to 3.38 g/L acetic acid and 0.67 g/L free fatty acids (FFAs) using 10 g/L xylose as substrate. Based on the concept of “nutrient supply-detoxification,” the engineered E. coli ∆4D (ACP-SCLAC) provided nutrient for the engineered P. putida KT∆ABZF (p2-a-J) and it acted to detoxify the substrates. Through this functional division and rational design of the metabolic pathways, the engineered P. putida-E. coli microbial consortium could produce 1.30 g/L of mcl-PHA from 10 g/L glucose and xylose. Finally, the consortium produced 1.02 g/L of mcl-PHA using lignocellulosic hydrolysate containing 10.50 g/L glucose and 10.21 g/L xylose as the substrate. The consortium developed in this study has good potential for mcl-PHA production and provides a valuable reference for the production of high-value biological products using inexpensive carbon sources.
Seismic vulnerability assessment of old churches in the twin cities of Bhubaneswar and Cuttack using the macroelemental approach
Authors: Mishra Mayank , Puneeth Rabilli , Ramana G. V.
Published: October 2022

Historic buildings are the cultural and traditional identity of a country. However, these buildings are vulnerable to earthquakes because of their aged structure, poor maintenance, and inadequate structural health monitoring. Therefore, seismic vulnerability assessment is a critical aspect in the restoration and retrofitting of heritage buildings. In this study, a comprehensive survey was performed to collect the data of old and historic church buildings in and around the twin cities of Bhubaneswar and Cuttack in Odisha for evaluating the performance of these structures against seismic activity. The macroelemental method for seismic vulnerability assessment was used to calculate the seismic vulnerability index of church buildings. The probable damage was estimated based on the obtained values of the mean damage grade according to the EMS-98 scale and were compared with the grade of damageability acquired using the rapid visual screening method for Indian conditions. Damage probability matrices were constructed to determine the probabilistic future damage. This study identified church buildings that require immediate renovation and retrofitting.
Lactate drives cellular DNA repair capacity: Role of lactate and related short-chain fatty acids in cervical cancer chemoresistance and viral infection
Authors: Ciszewski Wojciech M. , Sobierajska Katarzyna , Stasiak Anna , Wagner Waldemar
Published: October 2022

The characteristic feature of a cancer microenvironment is the presence of a highly elevated concentration of L-lactate in the tumor niche. The lactate-rich environment is also maintained by commensal mucosal microbiota, which has immense potential for affecting cancer cells through its receptoric and epigenetic modes of action. Some of these lactate activities might be associated with the failure of anticancer therapy as a consequence of the drug resistance acquired by cancer cells. Upregulation of cellular DNA repair capacity and enhanced drug efflux are the most important cellular mechanisms that account for ineffective radiotherapy and drug-based therapies. Here, we present the recent scientific knowledge on the role of the HCA1 receptor for lactate and lactate intrinsic activity as an HDAC inhibitor in the development of an anticancer therapy-resistant tumor phenotype, with special focus on cervical cancer cells. In addition, a recent study highlighted the viable role of interactions between mammalian cells and microorganisms in the female reproductive tract and demonstrated an interesting mechanism regulating the efficacy of retroviral transduction through lactate-driven modulation of DNA-PKcs cellular localization. To date, very few studies have focused on the mechanisms of lactate-driven enhancement of DNA repair and upregulation of particular multidrug-resistance proteins in cancer cells with respect to their intracellular regulatory mechanisms triggered by lactate. This review presents the main achievements in the field of lactate impact on cell biology that may promote undesirable alterations in cancer physiology and mitigate retroviral infections.
Optimizing interactions to protein binding sites by integrating docking-scoring strategies into generative AI methods
Authors: Sauer Susanne , Matter Hans , Hessler Gerhard , Grebner Christoph
Published: October 2022

The identification and optimization of promising lead molecules is essential for drug discovery. Recently, artificial intelligence (AI) based generative methods provided complementary approaches for generating molecules under specific design constraints of relevance in drug design. The goal of our study is to incorporate protein 3D information directly into generative design by flexible docking plus an adapted protein-ligand scoring function, thereby moving towards automated structure-based design. First, the protein-ligand scoring function RFXscore integrating individual scoring terms, ligand descriptors, and combined terms was derived using the PDBbind database and internal data. Next, design results for different workflows are compared to solely ligand-based reward schemes. Our newly proposed, optimal workflow for structure-based generative design is shown to produce promising results, especially for those exploration scenarios, where diverse structures fitting to a protein binding site are requested. Best results are obtained using docking followed by RFXscore, while, depending on the exact application scenario, it was also found useful to combine this approach with other metrics that bias structure generation into “drug-like” chemical space, such as target-activity machine learning models, respectively.
Fabrication of a lead-free ternary ceramic system for high energy storage applications in dielectric capacitors
Authors: Khan Azam , Gul Noor Shad , Luo Mao , Wu Jianbo , Khan Shahan Zeb , Manan Abdul , Wang Xiu-Jian , Khan Taj Malook
Published: October 2022

The importance of electroceramics is well-recognized in applications of high energy storage density of dielectric ceramic capacitors. Despite the excellent properties, lead-free alternatives are highly desirous owing to their environmental friendliness for energy storage applications. Herein, we provide a facile synthesis of lead-free ferroelectric ceramic perovskite material demonstrating enhanced energy storage density. The ceramic material with a series of composition (1-z) (0.94Na0.5Bi0.5TiO3-0.06BaTiO3)-zNd0.33NbO3, denoted as NBT-BT-zNN, where, z = 0.00, 0.02, 0.04, 0.06, and 0.08 are synthesized by the conventional solid-state mix oxide route. Microphases, microstructures, and energy storage characteristics of the as-synthesized ceramic compositions were determined by advanced ceramic techniques. Powder X-ray diffraction analysis reveals pure single perovskite phases for z = 0 and 0.02, and secondary phases of Bi2Ti2O7 appeared for z = 0.04 and 0.08. Furthermore, scanning electron microscopy analysis demonstrates packed-shaped microstructures with a reduced grain size for these ceramic compositions. The coercive field (Ec) and remnant polarization (Pr) deduced from polarization vs. electric field hysteresis loops determined using an LCR meter demonstrate decreasing trends with the increasing z content for each composition. Consequently, the maximum energy storage density of 3.2 J/cm3, the recoverable stored energy of 2.01 J/cm3, and the efficiency of 62.5% were obtained for the z content of 2 mol% at an applied electric field of 250 kV/cm. This work demonstrates important development in ceramic perovskite for high power energy storage density and efficiency in dielectric capacitors in high-temperature environments. The aforementioned method makes it feasible to modify a binary ceramic composition into a ternary system with highly enhanced energy storage characteristics by incorporating rare earth metals with transition metal oxides in appropriate proportions.
Clonorchis sinensis infection induces hepatobiliary injury via disturbing sphingolipid metabolism and activating sphingosine 1-phosphate receptor 2
Authors: Liu Ji-Xin , Liu Man , Yu Guo-Zhi , Zhao Qian-Qian , Wang Jian-Ling , Sun Yan-Hong , Koda Stephane , Zhang Beibei , Yu Qian , Yan Chao , Tang Ren-Xian , Jiang Zhi-Hua , Zheng Kui-Yang
Published: October 2022

Clonorchis sinensis (C. sinensis) infection induces severe hepatobiliary injuries, which can cause inflammation, periductal fibrosis, and even cholangiocarcinoma. Sphingolipid metabolic pathways responsible for the generation of sphingosine-1-phosphate (S1P) and its receptor S1P receptors (S1PRs) have been implicated in many liver-related diseases. However, the role of S1PRs in C. sinensis-mediated biliary epithelial cells (BECs) proliferation and hepatobiliary injury has not been elucidated. In the present study, we found that C. sinensis infection resulted in alteration of bioactive lipids and sphingolipid metabolic pathways in mice liver. Furthermore, S1PR2 was predominantly activated among these S1PRs in BECs both in vivo and in vitro. Using JTE-013, a specific antagonist of S1PR2, we found that the hepatobiliary pathological injuries, inflammation, bile duct hyperplasia, and periductal fibrosis can be significantly inhibited in C. sinensis-infected mice. In addition, both C. sinensis excretory-secretory products (CsESPs)- and S1P-induced activation of AKT and ERK1/2 were inhibited by JTE-013 in BECs. Therefore, the sphingolipid metabolism pathway and S1PR2 play an important role, and may serve as potential therapeutic targets in hepatobiliary injury caused by C. sinensis-infection.
Inspiratory muscle training in patients with heart failure: A systematic review and meta-analysis
Authors: Li Hui , Tao Lingling , Huang Yuewi , Li Ziyang , Zhao Jianrong
Published: October 2022

Objective

To explore the effect of inspiratory muscle training (IMT) on patients with heart failure and further explore the impact of IMT on patients with heart failure with preserved ejection fraction.

Methods

PubMed, EMBASE, Cochrane Library, CNKI, Wanfang and VIP databases were systematically searched. Randomized controlled trials of inspiratory muscle training in patients with heart failure were included. Revman 5.3 software was used to calculate the weighted mean difference (MD) of the combined effect size. The effects of IMT on the maximum oxygen uptake (peakVO2), maximum inspiratory pressure (PImax), ventilation efficiency (VE/VCO2), six-minute walking distance (6MWD), forced expiratory volume (FEV1), forced vital capacity (FVC) and quality of life in patients with heart failure were compared and analyzed.

Results

After systematic retrieval and screening, 17 studies were included in this study, and the quality of the included studies was good. The results showed that IMT could increase peakVO2 (MD 2.53; 95% CI 1. 54, 3. 51; P < 0.0001) and PImax (MD 17.25; 95% CI 13. 75, 20. 75; P < 0.00001); improve the VE/VCO2 (MD −4.22; 95% CI −6.78, −1.66; P = 0.001) and significantly improve the quality of life in patients with heart failure (MD −13.34; 95% CI −20.42, −6.26; P = 0.0002). However, the effect of IMT on 6MWD in patients with heart failure was not statistically significant (MD 74.45; 95% CI −12.88,161.79; P = 0.09), and the effect on lung function (FEV1 and FVC) was also not statistically significant (P = 0.08; P = 0.86). IMT had a more significant positive effect on peakVO2 (MD 2.98; 95% CI 1.63, 4.34; P < 0.0001) and quality of life (MD −14.52; 95% CI −18.53, −10.52; P < 0.00001) in patients with heart failure with preserved ejection fraction. Descriptive analysis suggested that IMT may positively affect dyspnoea in patients with heart failure. In addition, the choice of evaluation scale may affect the evaluation results of quality of life and dyspnoea.

Conclusion

IMT has a significant positive effect on respiratory status in patients with heart failure, but different dyspnoea and quality of life evaluation scales can affect the final evaluation results.
MedGraph: A semantic biomedical information retrieval framework using knowledge graph embedding for PubMed
Authors: Ebeid Islam Akef
Published: October 2022

Here we study the semantic search and retrieval problem in biomedical digital libraries. First, we introduce MedGraph, a knowledge graph embedding-based method that provides semantic relevance retrieval and ranking for the biomedical literature indexed in PubMed. Second, we evaluate our approach using PubMed's Best Match algorithm. Moreover, we compare our method MedGraph to a traditional TF-IDF-based algorithm. Third, we use a dataset extracted from PubMed, including 30 million articles' metadata such as abstracts, author information, citation information, and extracted biological entity mentions. We pull a subset of the dataset to evaluate MedGraph using predefined queries with ground truth ranked results. To our knowledge, this technique has not been explored before in biomedical information retrieval. In addition, our results provide some evidence that semantic approaches to search and relevance in biomedical digital libraries that rely on knowledge graph modeling offer better search relevance results when compared with traditional methods in terms of objective metrics.
Course assessment for skill transfer: A framework for evaluating skill transfer in online courses
Authors: Fischer Heather A. , Preston Kimberley , Staus Nancy , Storksdieck Martin
Published: October 2022

Science, technology, engineering, and mathematics (STEM) occupations are projected to grow over two times faster than the total for all occupations in the next decade. This will require reskilling and upskilling those currently in the workforce. In response, many universities are deliberately developing academic programs and individual courses focused on providing relevant skills that can be transferred to the workplace. In turn, developers of such programs and courses need ways to assess how well the skills taught in their courses translate to the workforce. Our framework, Course Assessment for Skill Transfer (CAST), is a suite of conceptual tools intended to aid course designers, instructors, or external evaluators in assessing which essential skills are being taught and to what extent. The overarching aim of the framework is to support skills transfer from the classroom to the workplace. This paper introduces the framework and provides two illustrative examples for applying the framework. The examples show that the framework offers a customizable structure for course facilitators and evaluators to assess the skills taught, learned, and retained based on their needs and the resources available to evaluate the quality and usefulness of course offerings in higher education.
Hypothesis: Metformin is a potential reproductive toxicant
Authors: Tavlo Maja , Skakkebæk Niels E. , Mathiesen Elisabeth R. , Kristensen David M. , Kjær Kurt H. , Andersson Anna-Maria , Lindahl-Jacobsen Rune
Published: October 2022

Metformin is the first-line oral treatment for type 2 diabetes mellitus and is prescribed to more than 150 million people worldwide. Metformin’s effect as a glucose-lowering drug is well documented but the precise mechanism of action is unknown. A recent finding of an association between paternal metformin treatment and increased numbers of genital birth defects in sons and a tendency towards a skewed secondary sex ratio with less male offspring prompted us to focus on other evidence of reproductive side effects of this drug. Metformin in humans is documented to reduce the circulating level of testosterone in both men and women. In experimental animal models, metformin exposure in utero induced sex-specific reproductive changes in adult rat male offspring with reduced fertility manifested as a 30% decrease in litter size and metformin exposure to fish, induced intersex documented in testicular tissue. Metformin is excreted unchanged into urine and feces and is present in wastewater and even in the effluent of wastewater treatment plants from where it spreads to rivers, lakes, and drinking water. It is documented to be present in numerous freshwater samples throughout the world – and even in drinking water. We here present the hypothesis that metformin needs to be considered a potential reproductive toxicant for humans, and probably also for wildlife. There is an urgent need for studies exploring the association between metformin exposure and reproductive outcomes in humans, experimental animals, and aquatic wildlife.
Necroptosis: A new target for prevention of osteoporosis
Authors: Hu Xinli , Wang Zheng , Kong Chao , Wang Yu , Zhu Weiguo , Wang Wei , Li Yongjin , Wang Wei , Lu Shibao
Published: October 2022

Multiple causes may contribute to osteoporosis, characterized by a loss in bone mass and density as a consequence of the degradation of bone microstructure and a resultant rise in bone fragility. Recently, increasing attention has been paid to the role of necroptosis in the development of osteoporosis. Necroptosis is orchestrated by a set of proteins known as receptor-interacting protein kinase (RIPK)1, RIPK3, and mixed lineage kinase domain-like protein (MLKL). A necrosome is formed by MLKL, RIPK1, RIPK3, and RIPK3-RIPK3. A dissociated MLKL forms pores in the plasma membrane and eventually leads to necroptosis after translocating from the necrosome. In this review, we discuss a detailed understanding of necroptosis and its associated processes, a better understanding of its interactions with osteoclasts, osteoblasts, and osteocytes, and the associations between necroptosis and diabetic osteoporosis, steroid-induced osteoporosis, and postmenopausal osteoporosis. In addition, a variety of experimental medicines capable of modulating crucial necroptosis processes are highlighted. It’s important to note that this is the first review paper to consolidate current data on the role of necroptosis in osteoporosis, and it offers fresh hope for the future treatment of this disease.
Vacuolization in embryos on days 3 and 4 of in vitro development: Association with stimulation protocols, embryo development, chromosomal status, pregnancy and neonatal outcomes
Authors: Chen Longbin , Zhang Shuoping , Gu Yifan , Peng Yangqin , Huang Zenghui , Gong Fei , Lin Ge
Published: October 2022

Study question

Is vacuolization in embryos on Days 3 and 4 associated with parent-related factors, stimulation protocols, embryo development, embryo ploidy, pregnancy and neonatal outcomes?

Study design, size, duration

This is a retrospective cohort study that comprised 5,703 embryos from 611 patients who underwent preimplantation genetic testing and time-lapse monitoring of their embryos from August 2017 to September 2021.

Main results

Embryo vacuolization on Days 3 and 4 is associated with the LH level on the day of the hCG trigger and the number of retrieved oocytes. Compared to vacuole-negative embryos, the rates of blastocyst formation and good-blastocyst formation was significantly lower in vacuole-positive embryos. We observed no significant difference in the rates of euploidy, implantation, ongoing pregnancy, and live birth between vacuole-positive and vacuole-negative embryos. In vacuole-positive embryos, the embryos of which the vacuole-positive blastomeres were involved in embryo compaction exhibited significantly higher mosaicism rate compared with those of which the vacuole-positive blastomeres were not involved in embryo compaction.

Conclusion

Vacuolization in embryos on Days 3 and 4 is associated with reduced blastocyst formation rate and high-quality blastocyst rate. Blastocysts had a low mosaicism rate if the vacuole-containing cells were rejected in compaction process, which supports the hypothesis that exclusion of abnormal blastomeres from compaction is a self-correction mechanism.