bluuebunny/crossref_metadata_2025 huggingface dataset:
Non-invasive monitoring of T cell differentiation through Raman spectroscopy
Authors: Pavillon Nicolas , Smith Nicholas I.
Published: February 2023

The monitoring of dynamic cellular behaviors remains a technical challenge for most established techniques used nowadays for single-cell analysis, as most of them are either destructive, or rely on labels that can affect the long-term functions of cells. We employ here label-free optical techniques to non-invasively monitor the changes that occur in murine naive T cells upon activation and subsequent differentiation into effector cells. Based on spontaneous Raman single-cell spectra, we develop statistical models that allow the detection of activation, and employ non-linear projection methods to delineate the changes occurring over a several day period spanning early differentiation. We show that these label-free results have very high correlation with known surface markers of activation and differentiation, while also providing spectral models that allow the identification of the underlying molecular species that are representative of the biological process under study.
Development of the automated temperature control system of the main gas pipeline
Authors: Fetisov Vadim , Ilyushin Yury V. , Vasiliev Gennadii G. , Leonovich Igor A. , Müller Johannes , Riazi Masoud , Mohammadi Amir H.
Published: February 2023

This article presents the results of a numerical experiment and an analysis of temperature fields (coolers for gas) using cooling elements in the case study gas pipeline. An analysis of the temperature fields demonstrated several principles for the formation of a temperature field, which indicates the need to maintain a relative temperature for gas pumping. The essence of the experiment was to install an unlimited number of cooling elements on the gas pipeline. The purpose of this study was to determine at what distance it is possible to install cooling elements for the optimal gas pumping regime, regarding the synthesis of the control law and the determination of the optimal location and assessment of control error depending on the location of the cooling elements. The developed technique allows for the evaluation of the developed control system's regulation error.
Composition and electronic structure of $${\rm SiO}_{\rm x}$$/$${\rm TiO}_{\rm y}$$/Al passivating carrier selective contacts on n-type silicon solar cells
Authors: Flathmann Christoph , Meyer Tobias , Titova Valeriya , Schmidt Jan , Seibt Michael
Published: February 2023

Carrier-selective and passivating SiO$$_{\rm x}$$

x

/TiO$$_{\rm y}$$

y

heterocontacts are an attractive alternative to conventional contacts due to their high efficiency potentials combined with relatively simple processing schemes. It is widely accepted that post deposition annealing is necessary to obtain high photovoltaic efficiencies, especially for full area aluminum metallized contacts. Despite some previous high-level electron microscopy studies, the picture of atomic-scale processes underlying this improvement seems to be incomplete. In this work, we apply nanoscale electron microscopy techniques to macroscopically well-characterized solar cells with SiO$$_{\rm x}$$

x

/TiO$$_{\rm y}$$

y

/Al rear contacts on n-type silicon. Macroscopically, annealed solar cells show a tremendous decrease of series resistance and improved interface passivation. Analyzing the microscopic composition and electronic structure of the contacts, we find that partial intermixing of the SiO$$_{\rm x}$$

x

and TiO$$_{\rm y}$$

y

layers occurs due to annealing, leading to an apparent thickness reduction of the passivating SiO$$_{\rm x}$$

x

. However, the electronic structure of the layers remains clearly distinct. Hence, we conclude that the key to obtain highly efficient SiO$$_{\rm x}$$

x

/TiO$$_{\rm y}$$

y

/Al contacts is to tailor the processing such that the excellent chemical interface passivation of a SiO$$_{\rm x}$$

x

layer is achieved for a layer thin enough to allow efficient tunneling through the layer. Furthermore, we discuss the impact of aluminum metallization on the above mentioned processes.
Ostreopsis Schmidt and Coolia Meunier (Dinophyceae, Gonyaulacales) from Cook Islands and Niue (South Pacific Ocean), including description of Ostreopsis tairoto sp. nov.
Authors: Verma A. , Hoppenrath M. , Smith K. F. , Murray J. S. , Harwood D. T. , Hosking J. M. , Rongo T. , Rhodes L. L. , Murray S. A.
Published: February 2023

It is important to decipher the diversity and distribution of benthic dinoflagellates, as there are many morphologically indistinct taxa that differ from one another in production of potent toxins. To date, the genusOstreopsiscomprises twelve described species, of which seven are potentially toxic and produce compounds presenting a threat to human and environmental health. In this study, isolates previously identified as “Ostreopsissp. 3” were sampled from the area where it was first reported, Rarotonga, Cook Islands, and have been taxonomically and phylogenetically characterised asOstreopsis tairotosp. nov. Phylogenetically, the species is closely related to “Ostreopsissp. 8”,O. mascarenensis, “O. sp. 4”,O. fattorussoi, O. rhodesiaeandO. cf.siamensis. Previously, it was considered a part of theO. cf.ovatacomplex but can be distinguished fromO. cf.ovatabased on the small pores identified on this study, and fromO. fattorussoiandO. rhodesiaebased on relative lengths of the 2′ plates. No known palytoxin -like compounds were detected in strains investigated in this study. Strains ofO. lenticularis, Coolia malayensisandC. tropicaliswere also identified and described. This study advances our knowledge of biogeography, distribution, and toxins ofOstreopsisandCooliaspecies.
Diverse flower-visiting responses among pollinators to multiple weather variables in buckwheat pollination
Authors: Miyashita Tadashi , Hayashi Shouta , Natsume Kae , Taki Hisatomo
Published: February 2023

Response diversity to environmental change among species is important for the maintenance of ecosystem services, but response diversity to changes in multiple environmental parameters is largely unexplored. Here, we examined how insect visitations to buckwheat flowers differ among species groups in response to changes in multiple weather variables and landscape structures. We found differences in responses to changes in weather conditions among insect taxonomic groups visiting buckwheat flowers. Beetles, butterflies, and wasps were more active in sunny and/or high-temperature conditions, whereas ants and non-syrphid flies showed the opposite pattern. When looking closely, the different response pattern among insect groups was itself shown to be different from one weather variable to another. For instance, large insects were responsive to temperatures more than small insects while smaller insects were responsive to sunshine duration more than large insects. Furthermore, responses to weather conditions differed between large and small insects, which agreed with the expectation that optimal temperature for insect activity depends on body size. Responses to spatial variables also differed; large insects were more abundant in fields with surrounding forests and mosaic habitats, whereas small insects were not. We suggest that response diversity at multiple spatial and temporal niche dimensions should be a focus of future studies of the biodiversity–ecosystem service relationships.
Computational study of the blood hemodynamic inside the cerebral double dome aneurysm filling with endovascular coiling
Authors: Rostamian Ali , Fallah Keivan , Rostamiyan Yasser , Alinejad Javad
Published: February 2023

The rupture of the aneurysm wall is highly associated with the hemodynamic feature of bloodstream as well as the geometrical feature of the aneurysm. Coiling is known as the most conventional technique for the treatment of intracranial cerebral aneurysms (ICA) in which blood stream is obstructed from entering the sac of the aneurysm. In this study, comprehensive efforts are done to disclose the impacts of the coiling technique on the aneurysm progress and risk of rupture. The computational fluid dynamic method is used for the analysis of the blood hemodynamics in the specific ICA. The impacts of the pulsatile blood stream on the high-risk region are also explained. Wall shear Stress (WSS) and Oscillatory shear index (OSI) factors are also compared in different blood viscosities and coiling conditions. According to our study, the hematocrit test (Hct) effect is evident (25% reduction in maximum WSS) in the two first stages (maximum acceleration and peak systolic). Our findings present that reduction of porosity from 0.89 to 0.79 would decrease maximum WSS by about 8% in both HCT conditions.
V2CTX MXene-based hybrid sensor with high selectivity and ppb-level detection for acetone at room temperature
Authors: Majhi Sanjit Manohar , Ali Ashraf , Greish Yaser E. , El-Maghraby Hesham F. , Mahmoud Saleh T.
Published: February 2023

High-performance, room temperature-based novel sensing materials are one of the frontier research topics in the gas sensing field, and MXenes, a family of emerging 2D layered materials, has gained widespread attention due to their distinctive properties. In this work, we propose a chemiresistive gas sensor made from V2CTx MXene-derived, urchin-like V2O5 hybrid materials (V2C/V2O5 MXene) for gas sensing applications at room temperature. The as-prepared sensor exhibited high performance when used as the sensing material for acetone detection at room temperature. Furthermore, the V2C/V2O5 MXene-based sensor exhibited a higher response (S% = 11.9%) toward 15 ppm acetone than pristine multilayer V2CTx MXenes (S% = 4.6%). Additionally, the composite sensor demonstrated a low detection level at ppb levels (250 ppb) at room temperature, as well as high selectivity among different interfering gases, fast response-recovery time, good repeatability with minimal amplitude fluctuation, and excellent long-term stability. These improved sensing properties can be attributed to the possible formation of H-bonds in multilayer V2C MXenes, the synergistic effect of the newly formed composite of urchin-like V2C/V2O5 MXene sensor, and high charge carrier transport at the interface of V2O5 and V2C MXene.
Prognostic CT features in patients with untreated thymic epithelial tumors
Authors: Dai Haiyang , Lan Bowen , Li Shengkai , Huang Yong , Jiang Guihua , Tian Junzhang
Published: February 2023

To determine the prognostic CT features in patients with untreated thymic epithelial tumors (TETs). Clinical data and CT imaging features of 194 patients with pathologically confirmed TETs were retrospectively reviewed. The subjects included 113 male and 81 female patients between 15 and 78 years of age, with a mean age of 53.8 years. Clinical outcomes were categorized according to whether relapse, metastasis or death occurred within 3 years after the first diagnosis. Associations between clinical outcomes and CT imaging features were determined using univariate and multivariate logistic regression analyses, while the survival status was analyzed by Cox regression. In this study, we analyzed 110 thymic carcinomas, 52 high-risk thymomas and 32 low-risk thymomas. Percentages of poor outcome and patient death in thymic carcinomas were much higher than those in patients with high-risk and low-risk thymomas. In the thymic carcinomas groups, 46 patients (41.8%) experienced tumor progression, local relapse or metastasis and were categorized as having poor outcomes; vessel invasion and pericardial mass were confirmed to be independent predictors by logistic regression analysis (p < 0.01). In the high-risk thymoma group, 11 patients (21.2%) were categorized as having poor outcomes, and the CT feature pericardial mass was confirmed to be an independent predictor (p < 0.01). In survival analysis, Cox regression showed that CT features of lung invasion, great vessel invasion, lung metastasis and distant organ metastasis were independent predictors for worse survival in the thymic carcinoma group (p < 0.01), while lung invasion and pericardial mass were independent predictors for worse survival in high-risk thymoma group. No CT features were related to poor outcome and worse survival in the low-risk thymoma group. Patients with thymic carcinoma had poorer prognosis and worse survival than those with high-risk or low-risk thymoma. CT can serve as an important tool for predicting the prognosis and survival of patients with TETs. In this cohort, CT features of vessel invasion and pericardial mass were related to poorer outcomes in those with thymic carcinoma and pericardial mass in those with high-risk thymoma. Features including lung invasion, great vessel invasion, lung metastasis and distant organ metastasis indicate worse survival in thymic carcinoma, whereas lung invasion and pericardial mass indicate worse survival in high-risk thymoma.
Application of self-organizing maps to AFM-based viscoelastic characterization of breast cancer cell mechanics
Authors: Weber Andreas , Vivanco Maria dM. , Toca-Herrera José L.
Published: February 2023

Cell mechanical properties have been proposed as label free markers for diagnostic purposes in diseases such as cancer. Cancer cells show altered mechanical phenotypes compared to their healthy counterparts. Atomic Force Microscopy (AFM) is a widely utilized tool to study cell mechanics. These measurements often need skilful users, physical modelling of mechanical properties and expertise in data interpretation. Together with the need to perform many measurements for statistical significance and to probe wide enough areas in tissue structures, the application of machine learning and artificial neural network techniques to automatically classify AFM datasets has received interest recently. We propose the use of self-organizing maps (SOMs) as unsupervised artificial neural network applied to mechanical measurements performed via AFM on epithelial breast cancer cells treated with different substances that affect estrogen receptor signalling. We show changes in mechanical properties due to treatments, as estrogen softened the cells, while resveratrol led to an increase in cell stiffness and viscosity. These data were then used as input for SOMs. Our approach was able to distinguish between estrogen treated, control and resveratrol treated cells in an unsupervised manner. In addition, the maps enabled investigation of the relationship of the input variables.
Contributors to self-report motor function after anterior cruciate ligament reconstruction
Authors: Niederer Daniel , Mengis Natalie , Wießmeier Max , Keller Matthias , Petersen Wolf , Ellermann Andree , Drenck Tobias , Schoepp Christian , Stöhr Amelie , Fischer Andreas , Achtnich Andrea , Best Raymond , Pinggera Lucia , Krause Matthias , Guenther Daniel , Janko Maren , Kittl Christoph , Efe Turgay , Schüttler Karl-Friedrich , Vogt Lutz , Behringer Michael , Stein Thomas
Published: February 2023

Numerous functional factors may interactively contribute to the course of self-report functional abilities after anterior cruciate ligament  (ACL)-reconstruction. This study purposes to identify these predictors using exploratory moderation-mediation models in a cohort study design. Adults with post unilateral ACL reconstruction (hamstring graft) status and who were aiming to return to their pre-injury type and level of sport were included. Our dependent variables were self-reported function, as assessed by the the KOOS subscales sport (SPORT), and activities of daily living (ADL). The independent variables assessed were the KOOS subscale pain and the time since reconstruction [days]. All other variables (sociodemographic, injury-, surgery-, rehabilitation-specific, kinesiophobia (Tampa Scale of Kinesiophobia), and the presence or absence of COVID-19-associated restrictions) were further considered as moderators, mediators, or co-variates. Data from 203 participants (mean 26 years, SD 5 years) were finally modelled. Total variance explanation was 59% (KOOS-SPORT) and 47% (KOOS-ADL). In the initial rehabilitation phase (< 2 weeks after reconstruction), pain was the strongest contributor to self-report function (KOOS-SPORT: coefficient: 0.89; 95%-confidence-interval: 0.51 to 1.2 / KOOS-ADL: 1.1; 0.95 to 1.3). In the early phase (2–6 weeks after reconstruction), time since reconstruction [days] was the major contributor (KOOS-SPORT: 1.1; 0.14 to 2.1 / KOOS-ADL: 1.2; 0.43 to 2.0). Starting with the mid-phases of the rehabilitation, self-report function was no longer explicitly impacted by one or more contributors. The amount of rehabilitation [minutes] is affected by COVID-19-associated restrictions (pre-versus-post: − 672; − 1264 to − 80 for SPORT / − 633; − 1222 to − 45 for ADL) and by the pre-injury activity scale (280; 103 to 455 / 264; 90 to 438). Other hypothesised contributors such as sex/gender or age were not found to mediate the time or pain, rehabilitation dose and self-report function triangle. When self-report function is rated after an ACL reconstruction, the rehabilitation phases (early, mid, late), the potentially COVID-19-associated rehabilitation limitations, and pain intensity should also be considered. As, for example, pain is the strongest contributor to function in the early rehabilitation phase, focussing on the value of the self-report function only may, consequently, not be sufficient to rate bias-free function.
Dual-modal molecular imaging and therapeutic evaluation of coronary microvascular dysfunction using indocyanine green-doped targeted microbubbles
Authors: Awen Alimina , Hu Dehong , Gao Duyang , Wang Zihang , Wu Yayun , Zheng Hairong , Guan Lina , Mu Yuming , Sheng Zonghai
Published: February 2023

We report ICG-doped targeted microbubbles as dual-modal probes for highly sensitive near-infrared fluorescence imaging and real-time ultrasound imaging of CMD in mouse models.
Catalytic routes towards polystyrene recycling
Authors: Marquez Carlos , Martin Cristina , Linares Noemi , De Vos Dirk
Published: February 2023

This minireview focuses on potential catalytic recycling processes for the production of styrene and other valuable aromatics from polystyrene (PS) waste, and it aims to lay the ground for PS recyclability and long-term sustainable PS production.
Hierarchically porous Ni foam-supported Co and Sn doped Ni3S2nanosheets for oxygen evolution reaction electrocatalysts
Authors: An Won Young , Lee Hyungwoo , Choi Sung Ryul , Choi Sungyong , Cho Hyun-Seok , Choi Minseok , Park Jun-Young
Published: February 2023

Electronic structure modification of Ni3S2with Co and Sn co-doping boosts OER property.
Dual-phased Mo2C/Mo3N2/C nanosheets for efficient electrocatalytic hydrogen evolution
Authors: Tian Guangyan , Yao Bingxue , Han Gaofeng , Li Yan , Zhang Kefeng , Meng Junping
Published: February 2023

Mo2C is a promising electrocatalyst for hydrogen evolution reaction (HER) on account of its Pt-like electronic features.
Controllable p-type doping of 2D MoS2via Sodium intercalation for optoelectronics
Authors: Ullah Salman , Li Ling , Wang Yixiu , Yang Xiaoyu , Tang Mingwei , Xiang Yuan , Yang Qing
Published: February 2023

We synthesized high-quality MoS2 flakes via the NaOH assisted CVD method. The morphological evolution of MoS2 flakes was investigated at different growth temperatures, and high-quality MoS2 were achieved with a photoresponsivity of 4.2 A W−1 and a specific detectivity of 8.1 × 108 Jones.
Self-reduction of Mn4+ to Mn2+: NaY9Si6O26:Mn2+ red phosphors with excellent thermal stability for NUV LEDs
Authors: Wu Sheng , Hu Shanshan , Liu Quan , Zhang Shuai , Jiang Dongliang , Zhang Guoxing , Le Yakun , Xiao Yao , Xiao Binli , Xiong Puxian , Chen Yan , Wang Yinzhen
Published: February 2023

Self-reduction in Mn2+ ion-doped silicate phosphors towards excellent thermal stability, the combination of which with near-UV (365 nm) LED chips proves it as a red pc-LED phosphor.
Grain growth of NpO2 and UO2 nanocrystals
Authors: Baumann Viktoria , Popa Karin , Cologna Marco , Rivenet Murielle , Walter Olaf
Published: February 2023

We report on the crystallite growth of nanometric NpO2 and UO2 powders.
Highly sensitive UV photodetector based on solution-processed bismuth oxyiodide epitaxial thin films
Authors: Sun Zaichun , Wang Yihao , Mei Bingchu
Published: February 2023

The as-fabricated photodetector based on high quality bismuth oxyiodide epitaxial thin film exhibited promising optoelectrical performance under UV light illumination and a tunable photoresponse mechanism depending on the film thickness.
Optimization of micro grid with distributed energy resources using physics based meta heuristic techniques
Authors: Vaish Jayati , Tiwari Anil Kumar , Siddiqui Khadim Moin
Published: February 2023

Recently, modern power systems depend heavily on MicroGrids (MGs), which can accommodate Distributed Energy Resources (DERs) economically and with high flexibility. MGs integrated with DERs can assist in enhancing energy security, significant cost savings, and reduction in emission of greenhouse gases. In this paper, the assessment of operating performance of proposed MG system with DERs is employed to investigate the multi‐objective problems of cost optimization and economic scheduling. A grid‐connected Micro‐grid (MG) combined with solar photovoltaic (PV), wind turbine (WT), fuel cell (FC), and Battery Energy Storage System (BESS) is implemented to model the problem. This proposed model is considered as a test system for cost optimization and battery charging/discharging optimization. The developed framework is presented as multi‐objective function with constraints that can be tackled using an effective optimization technique. The above stochastic multi‐objective problem is optimized using various commonly used Physics based Meta‐heuristic techniques such as Simulated Annealing (SA), Harmony Search (HS), Slime Mold Algorithm (SMA), Gravitational Search Algorithm (GSA), Black Hole Optimization (BHO), Sine Cosine Algorithm (SCA), Multiverse optimization (MVO) and Lightning Search Algorithm (LSA). The assessment of the aforementioned physics‐based optimization techniques used on the proposed MG test system is compared using the results. According to the analysis, Black Hole Optimization (BHO) and Lightning Search Algorithm (LSA) both provide greater cost savings overall and for battery charging, respectively. The suggested optimization methods will take the BESS charging/discharging pattern and total cost savings into account.
Jupiter’s interior from Juno: Equation-of-state uncertainties and dilute core extent
Authors: Howard S. , Guillot T. , Bazot M. , Miguel Y. , Stevenson D. J. , Galanti E. , Kaspi Y. , Hubbard W. B. , Militzer B. , Helled R. , Nettelmann N. , Idini B. , Bolton S.
Published: February 2023

Context. The Juno mission has provided measurements of Jupiter’s gravity field with an outstanding level of accuracy, leading to better constraints on the interior of the planet. Improving our knowledge of the internal structure of Jupiter is key to understanding its formation and evolution but is also important in the framework of exoplanet exploration.

Aims. In this study, we investigated the differences between the state-of-the-art equations of state and their impact on the properties of interior models. Accounting for uncertainty on the hydrogen and helium equation of state, we assessed the span of the interior features of Jupiter.

Methods. We carried out an extensive exploration of the parameter space and studied a wide range of interior models using Markov chain Monte Carlo simulations. To consider the uncertainty on the equation of state, we allowed for modifications of the equation of state in our calculations.

Results. Our models harbour a dilute core and indicate that Jupiter’s internal entropy is higher than what is usually assumed from the Galileo probe measurements. We obtain solutions with extended dilute cores, but contrary to other recent interior models of Jupiter, we also obtain models with small dilute cores. The dilute cores in such solutions extend to ~20% of Jupiter’s mass, leading to better agreement with formation–evolution models.

Conclusions. We conclude that the equations of state used in Jupiter models have a crucial effect on the inferred structure and composition. Further explorations of the behaviour of hydrogen–helium mixtures at the pressure and temperature conditions in Jupiter will help to constrain the interior of the planet, and therefore its origin.
Identifying approximate proper efficiency in an infinite dimensional space
Authors: Hoseinpoor Narges , Ghaznavi Mehrdad
Published: February 2023

The main idea of this article is to characterize approximate proper efficiency that is a widely used optimality concept in multicriteria optimization problems that prevents solutions having unbounded trade-offs. We analyze a modification of approximate proper efficiency for problems with infinitely many objective functions. We obtain some necessary and sufficient optimality conditions for this modification of approximate proper efficiency. This modified version of approximation guarantees the general characterizations of approximate properly efficient points as solutions to weighted sum problems and modified weighted Tchebycheff norm problems, even if there is an infinite number of criteria. The provided proofs concerning the modified definition show that if the number of the objective functions is infinite, then these results become invalid under the primary definition of approximate proper efficiency.
Dynamics of multi-scale vortical structures behind a barchan dune
Authors: Han Xiaolei , Li Jiawei , Rinoshika Hiroka , Zhou Yuyang , Zheng Yan , Dong Lin , Rinoshika Akira
Published: February 2023

In this study, multi-scale vortical structures and vortex dynamics around a fixed-bed barchan dune have been experimentally investigated based on the particle image velocimetry technique, wavelet transform, and the finite-time Lyapunov exponent method. It was found that the dynamic characteristics of a dune wake are predominated by large- and intermediate-scale coherent structures. Quadrant analysis of the Reynolds-stress distribution for the corresponding wavelet components revealed that ejection and sweep events are the main contributors to the whole field, while outward and inward interaction events just dominate the region near the dune crest. In addition, the process of ejection and sweeping motions associated with the turbulent bursting sequence can also be captured by applying proper orthogonal decomposition analysis of the decomposed velocity field for the different wavelet components. Finally, a continuous development process of the different wavelet scale structures in the shear layer was visualized in the Lagrangian framework. The small-scale waves grow exponentially and gradually develop into larger-scale vortices when convected downstream until the reattachment point, and larger-scale vortices break into the smaller ones.
Numerical study of drop impact on slippery lubricated surfaces
Authors: Islam Ahmed , Lian Yongsheng
Published: February 2023

We numerically study drop impact on slippery lubricated surfaces at varied impact speeds to comprehend the cloaking of the water drop by the lubricant. We employ a multi-material and multi-phase interface reconstruction method to capture the interaction between the drop and the lubricants of varying interfacial tensions. We demonstrate that cloaking occurs when lubricant water interfacial tensions are low and impact speeds are low. Our research demonstrates that the thickness of the encapsulating lubricant layer varies over time. At moderate impact speeds of 0.25 and 0.5 m/s, the drop displaces a large amount of lubricant, generating a lubricant–water jet, as we also demonstrate. At high impact speeds of 5 and 30 m/s, a secondary impingement forms, which displaces a significant amount of lubricant to reveal the underneath substrate that was not visible at lower impact speeds. Finally, we investigate the drop impact on lubricant infused micro-wells with varying spacing. We find that small spacing between the micro-well walls can limit lubricant drainage and displacement. The substrates with micro-wells exhibit far less splashing than those without. Furthermore, we demonstrate that micro-wells are better at preserving lubricants than substrates without micro-wells.
Effects of combustion on the near-wall turbulence and performance for supersonic hydrogen film cooling using large eddy simulation
Authors: Wei Jianfei , Zhang Silong , Zuo Jingying , Qin Jiang , Zhang Junlong , Bao Wen
Published: February 2023

Supersonic film cooling using fuel on board is an effective way to simultaneously shield the huge heat and momentum flux transported from the mainstream to the wall in a scramjet engine. The self-ignition and combustion of the injected fuel film will significantly change the turbulent transport behavior in the boundary layer. To reveal the effects of the boundary layer combustion on the near-wall turbulence and wall fluxes, large eddy simulations (LES) of the Burrows–Kurkov supersonic combustion experiment using hydrogen as a film are performed based on the in-house solver scramjetFoam. The solver successfully captures the additional skin friction reduction phenomenon induced by the boundary layer combustion compared to other numerical works using LES in the public literature. The results reveal that further increased anisotropy of turbulence combined with the low-density region contributes to a remarkable suppression of turbulent transport processes in the wall-normal direction. The self-ignition point of the hydrogen film is found to oscillate back and forth in a span of 80 mm, which significantly enhances turbulence in the boundary layer. However, the increased turbulent fluctuating velocity is mainly concentrated in the streamwise direction, while the other two components are suppressed instead. The findings are also essential for improving engineering computations based on the Reynolds averaged simulation method.
Experimental assessment of Theodorsen's function for uncoupled pitch–plunge motion
Authors: Daliri A. , Maghrebi M. J. , Soltani M. R.
Published: February 2023

The accuracy of Theodorsen's lift model for pure-pitch, pure-plunge and combined pitch–plunge oscillations of a two-dimensional model is compared with wind tunnel results. The reduced frequency of the oscillation was in the range of 0.01<k<0.15, and the freestream Reynolds number was in the range of 130 000<Re<400 000. The lift response to an uncoupled combined pitch–plunge motion (for which the frequency of pitch and plunge motions were not the same) is discussed using experimental results. The Theodorsen’s lift model is rewritten for the general uncoupled pitch–plunge motions by a linear superposition of all components of the airfoil bound circulation. Both amplitude and phase from the Theodorsen's function are compared with those of the wind tunnel data, and the results are discussed. The Theodorsen’s function is found to be a good estimator for both pure-pitch and pure-plunge motions. It further appropriately estimates the lift amplitude for the case of coupled pitch–plunge motion; however, the prediction is not accurate for the uncoupled pitch–plunge motion. A motion amplitude ratio is defined, which shows the level of aperiodicity of the motion. Discrepancy between experimental and analytical results increase with the reduction of the lift amplitude ratio and with the deviation of frequency ratio from unity.
Dual separation control and drag mitigation in high speed flows using viscoelastic materials
Authors: Walz James , Narayanaswamy Venkat
Published: February 2023

Boundary layer separation and friction drag form key delimiting phenomena that subvert the aerial platforms from achieving greater efficiency and accessing wider operation envelope. Both these phenomena are significantly aggravated in supersonic platforms due to the interactions between shock waves with the boundary layer that develops over the vehicle surface and within the engines. The present work demonstrates a new paradigm that leverages the native or programmable material properties of the aerostructures to engender simultaneous reduction in the separation scales and mitigation of skin friction drag. As a first step toward realizing this paradigm, the present work demonstrates, for the first time, the simultaneous skin friction drag mitigation in a Mach 2.5 boundary layer and control of shock induced boundary layer separation, both using viscoelastic implants placed under the flow. It is experimentally demonstrated that the appropriately chosen viscoelastic materials can simultaneously reduce the skin friction coefficient at the measurement location by 11% and mitigate the size of a large-scale separated flow by up to 28%. The reported performance matches the current generation flow effectors in both separation scale and skin friction mitigation. The present study opens a new application space for soft/programmable materials in high speed aerial vehicles.
Roles of hydrogen bonding interactions and hydrophobic effects on enhanced water structure strength in aqueous alcohol solutions
Authors: Yang Bo , Xing Lu , Wang Shenghan , Sun Chenglin , Men Zhiwei
Published: February 2023

The structure and dynamics of water in aqueous alcohol solutions were explored using two-dimensional Raman correlation spectroscopy (2D Raman-COS) combined with the density functional theory (DFT). The spectral changes in the H–O–H bending and O:H stretching modes demonstrated that ethanol and n-propanol induced an enhancement of the water structure compared to methanol. The extent of this effect was related to the length of the alkyl chain. Comparative studies with aqueous ethylene glycol solution revealed that an enhanced water structure stemmed mainly from hydrophobic effects rather than hydrogen bonding (H-bonding) interactions. Alcohol-induced water-specific structural transitions were further analyzed using 2D Raman-COS, which showed that the free OH and strong H-bond structure of water respond preferentially to changes in alcohol content, inducing a transition in the weak H-bond structure of water. In addition, the 2D Raman-COS results indicated that the CH3 stretching mode of alcohol responds preferentially to variations in water content compared to other C–H vibrational modes. Finally, the details of the alcohol-induced water structural transitions were calculated using DFT. The 2D Raman-COS combined with DFT calculations provided insight into alcohol-induced water structural transitions and can be easily extended to other studies of water-organic chemistry.
Increased light scattering in electrically stimulated beef longissimus muscle fibres contributes to the observed meat colour at grading
Authors: Hughes J. , McPhail N. , Watkins P. , Stark J. , Warner R. D.
Published: February 2023

Context Electrical stimulation is often used by meat processors to promote fast muscle pH decline and optimise meat quality. Meat colour can be made more acceptable by this process, but how this relates to the microstructure and light-scattering properties of muscle is still unknown. Aims To investigate the effect of electrical stimulation of beef carcasses on the meat colour at grading and the role of the muscle fibre microstructure and light scattering in determining colour differences. Methods Electrical stimulation inputs (electrical stimulation inputs (ES), n = 8; no electrical stimulation inputs (NS), n = 8) were applied to beef carcasses from female cattle of approximately 18–24 months of age. ES comprised electrical immobilisation, bleed rail electric simulation and hide puller rigidity probe, which have all been shown to increase pH fall post-mortem in beef carcasses. pH fall was monitored, the longissimus thoracis was graded at 20–22 h postmortem and measurements were made of colour, muscle-fibre structure and light scattering. Key results The decline of pH was increased in ES relative to NS, as indicated by lower pH at 2 h postmortem (5.83 vs 6.86 respectively, s.e. = 0.068; P < 0.05) as well as changes in both chromatic colour a* b* and achromatic (no colour) lightness in the muscle. Chromatic changes were evident as higher grader colour scores, increased redness (a*) and yellowness (b*) with higher levels of oxymyoglobin and lower levels of deoxymyoglobin. Achromatic changes were evident as increased lightness (L*) and surface reflectance (%R) at the meat surface, and increased global brightness within the muscle fibres. Conclusions Increased lightness and brightness in electrically stimulated muscles were likely to be due to formation of contraction nodes and distortion of muscle fibres, which changed the microstructure of muscle in ways that increased its light-scattering properties. Implications Consideration of the role of light scattering in determining beef colour at grading will advance understanding of how to improve this important quality trait.
Efficacy of priming wheat (Triticum aestivum) seeds with a benzothiazine derivative to improve drought stress tolerance
Authors: AL-Huqail Arwa Abdulkreem , Saleem Muhammad Hamzah , Ali Baber , Azeem Muhammad , Mumtaz Sahar , Yasin Ghulam , Marc Romina Alina , Ali Shafaqat
Published: February 2023

We evaluated the effects of different concentrations (0.05 and 0.15 mM) of a benzothiazine (BTh) derivative on wheat (Triticum aestivum L.) in normal (100% field water capacity, FWC) and drought (60% FWC) conditions. Various morphological and physiological characteristics, and the uptake of osmo-protectants and nutrients were measured under the two FWC conditions. Results show that the drought conditions significantly reduced plant growth, affected plant composition, reduced the concentrations of photosynthetic pigments and affected gaseous exchange attributes, stomatal behaviour, and uptake fluxes of essential nutrients, while increasing the contents of different osmo-protectants and enzymatic and non-enzymatic antioxidants to decrease the production of reactive oxygen species (ROS) within the cells/tissues. However, seed priming with BTh reduced water stress conditions by increasing plant growth and biomass, photosynthetic pigments, stomatal behaviour, different gaseous exchange attributes, and uptake fluxes of essential nutrients compared with unprimed plants. In addition, the plant has a strong antioxidant defense system, which further increased its activities under BTh derivative treatments, to scavenge ROS production and maintain cell turgor under water stress conditions. In conclusion, drought stress-induced oxidative stress and altered the growth of T. aestivum, whereas seed priming increased plant growth and antioxidant production by improving the plant tolerance to drought. We suggest that seed priming with a BTh derivative as an effective priming technique in T. aestivum for reducing drought stress tends to benefit a grower in terms of better growth to fulfil the market demand for food cereals.
Engineering biodegradable coatings for sustainable fertilisers
Authors: Islam Zahra F. , Cherepanov Pavel V. , Hu Hang-Wei
Published: February 2023

With the pressures of a changing global climate and ever-growing population, the need for sustainable agricultural practices that increase crop yields while decreasing greenhouse gas emissions are critical. Currently used practices to increase yields can often be problematic due to low nitrogen use efficiency or a potential overreliance on agrichemicals that can alter the community composition of a given ecosystem, although this is typically system and situation dependent. As such, the next generation of enhanced efficiency fertilisers that combine chemical, materials engineering and biological components are likely to be a game changer. Integral to their success is a better understanding of how plant–soil microbiomes interact with the new enhanced efficiency fertilisers, and how we can best tailor the fertilisers to suit different plant–soil combinations. In particular, the biodegradation properties of new fertiliser coatings must be given careful consideration so as to not further burden agricultural soils with microplastics or cause ecotoxicity problems. This perspective proposes novel, interdisciplinary strategies to generate highly efficient, biodegradable fertiliser coatings for use in the agricultural sector.
Growing soil organic carbon in dryland agricultural systems
Authors: Farrell Mark , Vadakattu Gupta
Published: February 2023

Soil organic carbon (SOC) plays a crucial role in dryland agricultural systems, improving resilience, productivity and delivering a range of ecosystem services including carbon (C) sequestration and broader ecosystem health. Although the net primary production (NPP) is the principal source of C inputs to soil, plant–microbe interactions can help increase NPP and stimulate plant C inputs to the soil through a variety of mechanisms. Additionally, the soil microbial community plays a crucial role in the loss (CO2 respiration) and stabilisation of SOC. With improved understanding of soil microbiomes and plant–microbe interactions, there are new emerging strategies in which microorganisms may be harnessed either directly or indirectly to increase the amount of C added and stabilised in dryland soils.
To B and not B2 – the Australian soil horizon system: history and review
Authors: Harms Ben
Published: February 2023

Soil horizon designation plays a key role in the communication of information about soils – hence the need for uniformity, consistency and clarity in the way soil horizons are defined and designated. Since its establishment in the late 19th century, the A-B-C schema for soil horizons has evolved with the realisation that traditional concepts of soil genesis embedded in the original system do not fit the breadth of current knowledge regarding soil development. Along with a more objective approach, there has been progress toward harmonisation, with considerable agreement between the two major international systems: FAO and USDA. Both use an A-E-B-C-R schema for mineral soil horizons, coupled with the prescriptive use of alphabetic suffixes. This schema is now adopted almost universally – Australia alone has retained the once widespread system of numerically designated horizons, first codified in the USA in 1937. The A1-A2-A3-B1-B2-B3-C-D-R schema for mineral horizons can therefore be regarded as the ‘Australian system’. Australia is also unique in the way it designates organic soil horizons. This review summarises the history of soil horizon designation and critically appraises the Australian system. It identifies ambiguity and inconsistency in the definition and allocation of horizons, and demonstrates that soil horizon notation in Australia is convoluted and complex. Pedology in Australia would benefit by aligning with international approaches including a simpler set of objectively defined master horizons, rationalised intergrade horizons and the more rigorous application of alphabetic suffixes. This would improve both the communication of soil profile information and the utility of soil databases.
Can conditioned taste aversion be deployed at a landscape level to mitigate the impact of invasive cane toads on northern quolls?
Authors: Indigo Naomi L. , Kelly Ella , Smith James , Webb Jonathan K. , Phillips Ben L.
Published: February 2023

Context Animals can be taught new behaviours to mitigate threatening processes. However, it is yet to be confirmed if such teaching can be deployed in the field. Here we test this possibility using the invasion of cane toads because they are highly toxic novel prey items to many predators across northern Australia. Aims Research has shown that training predators to avoid toads, using conditioned taste aversion (CTA), significantly improves the survival rates of individuals. We sought to determine if deployment of CTA baits, in situ, could reduce cane toad impacts on a mammalian predator, the northern quoll (Dasyurus hallucatus). Methods The work was conducted in the Kimberley, Western Australia, where we treated three quoll populations with training baits from November 2015–November 2017, and kept four populations as controls. We used camera traps and Bayesian hierarchal modelling to estimate the population size of quolls on up to four occasions before, and two occasions after, cane toad arrival. Key results We observed a 65% reduction in quoll population size at control sites and a 94% reduction at treatment sites: a significant effect of aversion training, but in the direction opposite to that expected. Conclusions Two complexities – decay of aversion, and individual variation – together, may explain our result. Our trials indicate that most animals are no longer averse within 120 days post-training. Earlier studies indicating that aversion training lasts longer may have inadvertently observed innate (i.e. genetically based) aversion to cane toads. Another possibility is that our dose rate of thiabendazole within the CTA baits was, in fact, too low; or the result may be an artefact of the non-random assignment of treatment and control groups. Ultimately, there is no way of determining exactly why our outcome occurred without further laboratory/captive trails. Regardless, our study demonstrates a failure of CTA training to mitigate the impact of cane toads on northern quolls in this system. Implications Our result calls into question the value of this approach for conserving quoll populations, at least in its current form. More generally, our results point to the often-unexpected complexities encountered as ideas progress from captive trials to field deployment.
Is regional variability in environmental conditions driving differences in the early body condition of endemic Australian fur seal pups?
Authors: Wall Demelza , Thalmann Sam , Wotherspoon Simon , Lea Mary-Anne
Published: February 2023

Context Good body condition in juvenile marine mammals is crucial for survival and, therefore, population demography. Australian fur seals, endemic to Australia, recently established a breeding colony at the southern edge of their range, at The Needles, a small group of islands in south-west Tasmania (43.6614°S) and a significant distance from their core breeding range in Bass Strait. Aims We aimed to compare pup body condition at two breeding colonies, distinct in time since establishment and latitude. Specific aims were to: (1) establish the timing of peak pupping, to compare condition of known-age pups, and determine a baseline at The Needles; (2) investigate pup body condition over time at an established colony; and (3) gain insight into the effects of environmental conditions on pup body condition. Methods We conducted a colony comparison of pup body condition using condition indices at The Needles and an established breeding colony in Bass Strait, Tenth Island, for the 2019/20 and 2020/21 breeding seasons. Pup body condition was quantified at Tenth Island over 18 years (2003–2020) using a long-term morphometric dataset. To establish breeding phenology at these two colonies, we determined peak pupping date for the 2019/20 breeding season using daily pup counts. We assessed the effect of environmental parameters on body condition for the long-term dataset. Key results Pups from The Needles displayed significantly higher body condition than those from Tenth Island, despite similar peak pupping date. Breeding phenology was consistent with published timing for Australian fur seals. Pup body condition at Tenth Island over the 2-year colony comparison was comparable to the historical average. Environmental drivers that affect maternal foraging efficiency are linked to pup body condition. Conclusions Higher pup body condition at The Needles is likely underpinned by better foraging conditions resulting in increased pup provisioning levels. Our results indicate that south-west Tasmania is a region of foraging and emerging breeding importance for Australian fur seals. Implications Future research to monitor pup body condition, maternal foraging behaviour and ecosystem productivity at The Needles will help to provide greater understanding of likely population trajectories at this southernmost breeding site for Australian fur seals.