bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sustainable resource production for manufacturing bioactives from micro‐ and macroalgae: Examples from harvesting and cultivation in the Nordic region
Authors: Chauton Matilde Skogen , Forbord Silje , Mäkinen Sari , Sarno Antonio , Slizyte Rasa , Mozuraityte Revilija , Standal Inger Beate , Skjermo Jorunn 
Published: March 2021

AbstractMicro‐ and macroalgae are a great and important source of raw material for manufacturing of bioactives and ingredients for food, feed, cosmetics, or pharmaceuticals. Macroalgae (or seaweeds) have been harvested locally from wild stocks in smaller volumes for a long time, and a production chain based on cultivated seaweed for the harvest of considerably larger amounts is in progress for several species. Microalgae and cyanobacteria such as Spirulina have been produced in “backyard ponds” for use in food and feed also for a long time, and now we see the establishment of large production plants to control the cultivation process and increase the production yields. There is also a shift from harvesting or cultivation centered in warmer, sunnier areas to increasing exploitation of natural resources in temperate to boreal regions. In locations with strong seasonal variations in solar irradiance and temperatures, we need to develop procedures to maximize the biomass production in the productive seasons and ensure efficient stabilization of the biomass for year‐round processing and product manufacturing. Industrialized biomass production and large‐scale manufacturing of bioactives also mean that we must employ sustainable, cost‐effective, and environmentally friendly processing methods, including stabilization and extraction methods such as ensiling and subcritical water extraction (SWE) and advanced analytic tools to characterize the products. These topics are focus areas of the Nordic Centre of Excellence (NCoE) NordAqua, and here we present a review of current activities in the field of micro‐ and macroalgae biomass production sectors illustrated with some of our experiences from the NordAqua consortium.
Maintaining a protective state for human periodontal tissue
Authors: Yamamoto Matsuo , Aizawa Ryo 
Published: March 2021

AbstractPeriodontitis, caused by infection with periodontal pathogens, is primarily characterized by inflammatory bone resorption and destruction of connective tissue. Simply describing periodontitis as a specific bacterial infection cannot completely explain the various periodontal tissue destruction patterns observed. Periodontal tissue damage is thought to be caused by various factors. In recent years, research goals for periodontal pathogens have shifted from searching for specific pathogens to investigating mechanisms that damage periodontal tissues. Bacteria interact directly with the host in several ways, influencing expression and activity of molecules that evade host defenses, and destroying local tissues and inhibiting their repair. The host's innate and acquired immune systems are important defense mechanisms that protect periodontal tissues from attack and invasion of periodontal pathogens, thus preventing infection. Innate and acquired immunity have evolved to confront the microbial challenge, forming a seamless defense network in periodontal tissues. In the innate immune response, host cells quickly detect, via specialized receptors, macromolecules and nucleic acids present on bacterial cell walls, and this triggers a protective, inflammatory response. The work of this subsystem of host immunity is performed mainly by phagocytes, beta‐defensin, and the complement system. In addition, the first line of defense in oral innate immunity is the junctional epithelium, which acts as a physical barrier to the entry of oral bacteria and other nonself substances. In the presence of a normal flora, junctional epithelial cells differentiate actively and proliferate apically, with concomitant increase in chemotactic factor expression recruiting neutrophils. These immune cells play an important role in maintaining homeostasis and the protective state in periodontal tissue because they eliminate unwanted bacteria over time. Previous studies indicate a mechanism for attracting immune cells to periodontal tissue with the purpose of maintaining a protective state; although this mechanism can function without bacteria, it is enhanced by the normal flora. A better understanding of the relationship between the protective state and its disruption in periodontal disease could lead to the development of new treatment strategies for periodontal disease.
Minimally invasive tenotomy of the tibial insertion of the semitendinosus muscle: An ex vivo study in horses
Authors: Zetterström Sandra M. , Boone Lindsey H. , Weatherall Kathleen M. , Caldwell Fred J. 
Published: March 2021

AbstractObjectiveTo describe a minimally invasive technique for semitendinosus tenotomy with ultrasonographic guidance and to evaluate procedural complications.Study designExperimental study.Sample populationCadaveric equine hind limbs (n = 16).MethodsA stab incision was performed distocaudal to the tibial insertion of the semitendinosus muscle with ultrasonographic assistance. After transection of the tendon with an arthroscopic retrograde knife, the tendon edges palpably retracted, and complete transection was confirmed by ultrasound. Limbs were dissected to confirm the degree of tendon transection and to identify iatrogenic trauma to surrounding soft tissues.ResultsTenotomy was complete in all limbs, resulting in a palpable gap forming between tendon edges. Superficial iatrogenic laceration to the underlying gracilis muscle (n = 2) or gracilis fascia (n = 1) was apparent in 3 of 16 limbs.ConclusionUltrasound‐assisted tenotomy of the tibial insertion of the semitendinosus muscle was reliably performed in a minimally invasive fashion with minor iatrogenic damage.Clinical significanceMinimally invasive tenotomy of the semitendinosus muscle can be performed with ultrasonographic assistance and should be considered as an alternative technique for surgical management of fibrotic semitendinosus myopathy.
The equine navicular apparatus as a premier enthesis organ: Functional implications
Authors: Osborn Michelle L. , Cornille Jean Luc , Blas‐Machado Uriel , Uhl Elizabeth W. 
Published: March 2021

AbstractNavicular syndrome has been traditionally characterized by progressive lameness with chronic degeneration of the navicular bone. Advances in imaging techniques have revealed that its associated soft tissue structures are also affected. This distribution of lesions is explained by conceptualizing the equine navicular apparatus as an enthesis organ that facilitates the dissemination of mechanical stress throughout the tissues of the foot. The navicular apparatus has the same structural adaptations to mechanical stress as the human Achilles tendon complex. These adaptations efficiently dissipate mechanical force away from the tendon's bony attachment site, thereby protecting it from failure. The comparison of these two anatomically distinct structural systems demonstrates their similar adaptations to mechanical forces, and illustrates that important functional insights can be gained from studying anatomic convergences and cross‐species comparisons of function. Such a functional conceptualization of the equine navicular apparatus resolves confusion about the diagnosis of navicular syndrome and offers insights for the development of mechanically based therapies. Through comparison with the human Achilles complex, this review (1) re‐conceptualizes the equine navicular apparatus as an enthesis organ in which mechanical forces are distributed throughout the structures of the organ; (2) describes the relationship between failure of the navicular enthesis organ and lesions of navicular syndrome; (3) considers the therapeutic implications of navicular enthesis organ degeneration as a form of chronic osteoarthritis; and based upon these implications (4) proposes a focus on whole body posture/motion for the development of prehabilitative and rehabilitative therapies similar to those that have already proven effective in humans.
Orthogonal Functions Used in the Solution of Linear Difference Problems
Authors: Benscoter S. U. 
Published: March 2021

Abstract
A method of solution of linear difference equations is presented in which the solution is assumed in terms of a finite set of orthogonal functions which satisfy the boundary conditions. A formula for the latent roots of the matrix of the system of equations is obtained. A simple formula is then derived for the reciprocal matrix in terms of the latent roots and latent vectors. A simple numerical example is presented.
Vibration of a Beam With Concentrated Mass, Spring, and Dashpot
Authors: Young Dana 
Published: March 2021

Abstract
An analytical method is developed for determining the natural frequencies of a composite system which consists of a uniform beam with a concentrated mass, spring, and dashpot attached at any point along the length of the beam. The method makes use of a series expansion in terms of the set of orthogonal functions which represent the normal modes of vibration of the beam alone. Numerical examples are given for a beam with a combined concentrated mass and spring, for a beam with two concentrated masses, and for a beam with an attached dashpot.
Experimental Studies of Biaxially Stressed Mild Steel in the Plastic Range
Authors: Fraenkel S. J. 
Published: March 2021

Abstract
This paper describes static tests of tubular specimens of medium steel under biaxial stresses and at room temperature. The purposes of the tests were: (1) to obtain an experimental check on the so-called “third rule of plastic flow;” (2) to study the absorption of energy as a function of the biaxial stress ratio; and (3) to determine the effect of the path of loading as symbolized by the strain path. Within the range of conditions investigated, the path of loading was found to be immaterial. A relation between strain energies absorbed under biaxial and uniaxial stress states up to a common maximum strain is tentatively formulated.
Behavior of Steel Under Biaxial Stress as Determined by Tests on Tubes
Authors: Davis H. E. , Parker E. R. 
Published: March 2021

Abstract
The experimental work is described and results presented for tests on twelve 5¼-in-diam thin-walled tubes of low-carbon steel subjected to various conditions of biaxial stress. These experiments composed the “pilot” series of tests in a larger investigation on the behavior of ship-plate steel under multiaxial stress conditions. The ductility of the metal under various biaxial stress conditions and at two temperatures, 70 F and −138F, is reported. The evidence indicates that the metal is reasonably ductile, even at the low temperature, provided it is subjected only to a state of plane stress. If a state of triaxial stress is induced by restraint or by discontinuities in the material, the ductility may be greatly reduced at the low temperature. Evidence is presented to indicate that fracture may occur either by shear or by cleavage, depending upon the stress and temperature conditions. In a majority of cases, reasonable prediction of the stress-strain behavior of the metal in the plastic range can be made for various biaxial stress conditions from the data of the simple tension test, by use of the modified octahedral-shear concept.
A Generalized Deformation Law
Authors: Davis E. A. 
Published: March 2021

Abstract
According to Hooke’s law the magnitude of infinitesimal elastic strains depends upon two independent constants. In this paper equations are developed which express the magnitude and the distribution of the strains in terms of two independent functions of the stresses. One function is related to the stress-strain diagram while the other is concerned with the distribution of the strains in a state of combined stress. The equations are easily adaptable to the relations between the strain rates and the stresses in combined stress-creep tests. It is the opinion of the author that two independent functions are necessary and that the behavior under a state of combined stress cannot be predicted from data obtained in pure-tension tests.
Unsteady Steam Turbine Optimization Using High-Fidelity Computational Fluid Dynamics
Authors: Iranidokht Vahid , Papagiannis Ilias , Kalfas Anestis I. , Abhari Reza S. , Senoo Shigeki , Momma Kazuhiro 
Published: March 2021

Abstract
This paper presents the computational methodology and experimental investigations accomplished to enhance the efficiency of a turbine stage by applying non-axisymmetric profiling on the rotor hub wall. The experimental setup was a two-stage axial turbine, which was tested at “LISA” test facility at ETH Zurich. The first stage was considered to create the flow history for the second stage, which was the target of the optimization. The hub cavity of the second stage was designed with large dimensions as a requirement of a steam turbine. The goal was to optimize the interaction of the cavity leakage flow with the rotor passage flow to reduce the losses and increase efficiency. The computational optimization was completed using a genetic algorithm coupled with an artificial neural network on the second stage of the test turbine. Unsteady time-accurate simulations were performed using in-house developed “MULTI3” solver. Besides implementing all geometrical details (such as hub and tip cavities and fully 3D blade geometries) from the experimental setup into the computational model, it was learned that the unsteady upstream effect could not be neglected. A novel approach was introduced using unsteady inlet boundary conditions to consider the multistage effect while reducing the computational cost to half. The importance of this implementation was tested by performing a steady simulation on the optimized geometry. The predicted efficiency gain from steady simulations was 4.5 times smaller (and negligible) compared to the unsteady approach. Excluding the cavity geometry was also assessed in a different simulation setup showing 3.9% over-prediction in the absolute efficiency value. Comprehensive steady and unsteady measurements were performed utilizing pneumatic, fast response aerodynamic probe (FRAP), and fast response entropy probe (FENT) on the baseline and profiled test cases. The end wall profiling was found to be successful in weakening the strength of the hub passage vortex by a 19% reduction in the under-over turning. As a result, the blockage was reduced near the hub region leading to more uniform mass flow distribution along the span. The flow angle deviations at the higher span position were also corrected due to better control of the flow angles. Furthermore, the improvements were confirmed by reductions in entropy, secondary kinetic energy, and pressure unsteadiness. The accurate computational implementations led to an excellent agreement between the predicted and measured efficiency gain.
Surface Texture Characterization of Metal Selective Laser Melted Part With Varying Surface Inclinations
Authors: Narasimharaju Shubhavardhan Ramadurga , Liu Weidong , Zeng Wenhan , See Tian Long , Scott Paul , Jiang Xiangqian (Jane) , Lou Shan 
Published: March 2021

Abstract
Additive manufacturing offers the advantage of infinite freedom to design and fabricate complex parts at reduced lead-time. However, the surface quality of additively manufactured parts remains well behind the conventionally processed counterparts. This paper aims to systematically investigate the impact of varying surface inclination angles with respect to the build direction on the resultant surface textures. A bespoke metal truncheon artifact with inclination angles varying from 0 deg to 180 deg was built by selective laser melting. Focus variation microscopy was used to measure the topography of inclined surfaces with a tilt angle of up to 132 deg. The measurement data were then analyzed to characterize the staircase effect and the particles adherent to the artifact surface. Areal surface texture parameters, including height parameters, spatial parameters, functional parameters, and feature parameters, were explored to quantify the general surface topography, the staircase effect, and the particle features. The areal surface texture characterization and particle analysis reveal the resulted surface topographies are strongly correlated with the surface inclination angles.
Influence of Paint Baking on the Energy Absorption and Failure Mode of Resistance Spot Welds in TRIP1180 Steel
Authors: Marshall D. V. , Bhattacharya D. , Speer J. G. 
Published: March 2021

Abstract
Resistance spot welds (RSWs) in advanced high strength steels frequently exhibit interfacial failure during cross-tension testing: a mode of fracture associated with low-energy absorption. Automotive assembly lines include a paint application and baking cycle after the vehicle assembly and joining processes to cure paint and any adhesives used for assembly. In this article, the effects of a typical baking cycle: 180 °C for 20 min, on the failure mode and energy absorption during cross-tension testing of RSWs made in a TRIP1180 steel are reported. Further, short-time baking cycles of 30 s, 90 s, and 4 min were employed to investigate how quickly these baking effects are activated. RSWs, which exhibited interfacial failure and a low-energy absorption of 30.9 J in the as-welded condition, saw a change in a failure mode to partial interfacial failure and a 260% increase in energy absorption after baking for 30 s. After baking for a longer time (4 min), welds failed by button pull-out and exhibited a 296% increase in energy absorption during cross-tension testing. Baking for the full 20 min resulted in no additional improvement than was observed in the 4 min condition. The mechanisms responsible for the majority of the improvement in weld performance during baking are found to be activated after only 30 s of baking.
Milling Force Prediction Model for Five-Axis Machining of Freeform Surface Considering Mesoscopic Size Effect
Authors: Guo Minglong , Wei Zhaocheng , Wang Minjie , Wang Jia , Liu Shengxian 
Published: March 2021

Abstract
The core parts with the characteristic of freeform surface are widely used in the major equipment of various fields. Cutting force is the most important physical quantity in the five-axis CNC machining process of core parts. Not only in micro-milling, but also in macro-milling, there is also an obvious size effect, especially in medium- and high-speed milling, which is frequently ignored. In this paper, the milling force prediction model for five-axis machining of a freeform surface with a ball-end mill considering the mesoscopic size effect is established. Based on the characteristics of cutting thickness in macro-milling, a new dislocation density correction form is proposed, and a new experiment is designed to identify the dislocation density correction coefficient. Therefore, the shear stress calculated in this paper not only reflects the cutting dynamic mechanical characteristics but also considers the mesoscopic size effect. A linear function is proposed to describe the relationship between friction coefficient and cutting speed, cutter rake angle, and cutting thickness. Considering cutter run-out, the micro-element cutting force in the shear zone and plough zone are analyzed. The cutting geometry contact between the freeform surface and the ball-end mill is analyzed analytically by the space limitation method. Finally, the total milling force is obtained by summing all the force vectors of cutting edge micro-elements within the in-cut cutting edge. In the five-axis machining experiment of freeform surface, the theoretically predicted results of milling forces are in good agreement with the measured results in trend and amplitude.
Design Optimization and Performance Analysis of a Multi-Kilowatt Thermoacoustic Electric Generator Using DeltaEC Model
Authors: Somu Srinath , Lacoste Deanna , Saxena Saumitra , Roberts William L. , Keolian Robert M. 
Published: March 2021

AbstractWaste heat recovery from power plants and industries requires a new type of electricity generator and related technological developments. The current research work is aimed at the design of a multi-kilowatt thermoacoustic electric generator, which can be employed as the bottoming cycle of a gas turbine power plant or for industrial waste heat recovery. The proposed device converts thermal energy into acoustic power and subsequently uses a piezoelectric alternator to convert acoustic power into electricity. The challenge in designing such a device is that it has to be acoustically balanced. The performance of the device is greatly affected by numerous parameters such as frequency of the traveling acoustic wave, heat exchanger parameters, regenerator dimensions, and acoustic feedback loop. The proposed device is a lab-scale demonstration targeted to produce few kilowatts of electric power from a 20 kWth heat source. DeltaEC software is used to achieve the acoustically balanced configuration of the device. The DeltaEC model outcomes are used to arrive at the optimized design of the device and its components. The analytical method, the optimized geometrical dimensions of thermoacoustic components, and the minimum required conditions of heat source input are presented in this paper.
Nonlinear Interactions of Lamb Waves With a Delamination in Composite Laminates
Authors: Gangwar Akhilendra S. , Agrawal Yamnesh , Joglekar D. M. 
Published: March 2021

AbstractIn view of their higher sensitivity in localizing an incipient damage, methods of non-destructive evaluation based on the nonlinear wave-damage interactions have been of continued interest in the recent past. In this paper, the propagation of guided waves through a delamination with contacting interfaces is studied numerically using a finite element-based framework. In particular, influence of the interlaminar location of the delamination on the nonlinear acoustic features in the response spectrum is investigated in detail. The numerical framework is validated by an in-house experimentation performed on a unidirectional glass fiber reinforced polymer (GFRP) laminate containing a through-width delamination. A parameter, referred to as the nonlinearity index (NI), is defined for quantifying the strength of the nonlinear wave-damage interactions and its dependence on the interlaminar location of the delamination is studied across a range of interrogation frequencies. The notion of contact energy intensity is introduced and further used for justifying the trends of variation of the NI obtained numerically and observed experimentally. Results indicate that two fundamental parameters govern the underlying contact phenomenon; they are the phase difference between the wave packets passing through the two sub-laminates and the flexural rigidities of the two sub-laminates present at the site of the delamination defect. While the former controls the relative displacement between the two sub-laminates, the latter governs the propensity of collisions between the two sub-laminates. Finally, a diametric effect of these two parameters on the generation of nonlinear harmonic signals with varying interlaminar locations of the delamination is brought out.
Experiments With the Integration of Reasoning, Optimization and Generalization in Process Planning
Authors: Váncza József , Márkus András 
Published: March 2021

Abstract
The paper describes a feature-based process planning model and planning methods as verified in a prototype system with the following distinctive properties: (1) reasoning over a detailed model of the part, the manufacturing processes and resources, (2) detection of conflicts and combinatorial conflict resolution among pieces of technological advice, (3) optimization of the manufacturing cost with a genetic algorithm, (4) generalization of plans by omitting incidental detail. Generalization, being the newest development in the system, is discussed more thoroughly. While the focus of attention is on the fundamental assumptions, the technical feasibility of the approach is illustrated by an example.