bluuebunny/crossref_metadata_2025 huggingface dataset:
Interrogating the Egypto-Sudanic Arabic Connection
Authors: Leddy-Cecere Thomas A.
Published: July 2021

The Arabic dialectology literature repeatedly asserts the existence of a macro-level classificatory relationship binding the Arabic speech varieties of the combined Egypto-Sudanic area. This proposal, though oft-encountered, has not previously been formulated in reference to extensive linguistic criteria, but is instead framed primarily on the nonlinguistic premise of historical demographic and genealogical relationships joining the Arabic-speaking communities of the region. The present contribution provides a linguistically based evaluation of this proposed dialectal grouping, to assess whether the postulated dialectal unity is meaningfully borne out by available language data. Isoglosses from the domains of segmental phonology, phonological processes, pronominal morphology, verbal inflection, and syntax are analyzed across six dialects representing Arabic speech in the region. These are shown to offer minimal support for a unified Egypto-Sudanic dialect classification, but instead to indicate a significant north–south differentiation within the sample—a finding further qualified via application of the novel method of Historical Glottometry developed by François and Kalyan. The investigation concludes with reflection on the implications of these results on the understandings of the correspondence between linguistic and human genealogical relationships in the history of Arabic and in dialectological practice more broadly.
Quality of L2 Input and Cognitive Skills Predict L2 Grammar Comprehension in Instructed SLA Independently
Authors: Kersten Kristin , Schelletter Christina , Bruhn Ann-Christin , Ponto Katharina
Published: July 2021

Input is considered one of the most important factors in the acquisition of lexical and grammatical skills. Input has been found to interact with other factors, such as learner cognitive skills and the circumstances where language is heard. Language learning itself has sometimes been found to enhance cognitive skills. Indeed, intensive contact with another language has been found to sometimes boost cognitive skills, even in intensive instructed settings, such as immersion programs (bilingual advantage hypothesis). In this paper, we report a cross-sectional study to assess grammar learning of 79 fourth grade German students learning L2 English in two immersion schools. Verbal teacher input was assessed using the Teacher Input Observation Scheme (TIOS, Items 14–25), and the learners’ L2 grammar comprehension was tested with the ELIAS Grammar Test II. Cognitive skills, including phonological awareness, working memory, and non-verbal intelligence, were determined using standardized assessment procedures. The results show that verbal input quantity and quality correlated significantly with the learners’ L2 grammar comprehension. None of the cognitive skills moderated the effect of input on grammar comprehension but all predicted it independently. The combination of L2 input and phonological awareness was found to be the most robust predictor of L2 grammar comprehension.
Recursion and the Definition of Universal Prosodic Categories
Authors: Cheng Lisa Lai-Shen , Downing Laura J.
Published: July 2021

It is widely agreed that prosodic constituents should mirror syntactic constituents (unless high-ranking prosodic constraints interfere). Because recursion is a feature of syntactic representations, one expects recursion in prosodic representations as well. However, it is of current controversy what kinds of syntactic representation motivate prosodic recursion. In this paper, the use of Phonological Phrase recursion is reviewed in several case studies, chosen because prosodic recursion mostly does not reflect syntactic recursion as defined in current syntactic theory. We provide reanalyses that do not appeal to prosodic recursion (unless syntactically motivated), showing that Phonological Phrase recursion is not necessary to capture the relevant generalizations. The more restrictive use of prosodic recursion we argue for has the following conceptual advantages. It allows for more consistent cross-linguistic generalizations about the syntax–prosody mapping so that prosodic representations more closely reflect syntactic ones. It allows the fundamental syntactic distinctions between clause (and other phases) and phrase to be reflected in the prosodic representation, and it allows cross-linguistic generalizations to be made about the prosodic domain of intonational processes, such as downstep and continuation rise.
Neuroimaging Studies of Nonsuicidal Self-Injury in Youth: A Systematic Review
Authors: Brañas Marcelo J. A. A. , Croci Marcos S. , Ravagnani Salto Ana Beatriz , Doretto Victoria F. , Martinho Eduardo , Macedo Marcos , Miguel Euripedes C. , Roever Leonardo , Pan Pedro M.
Published: July 2021

Nonsuicidal self-injury (NSSI) is prevalent and affects mainly the youth population. It is prospectively associated with suicide attempts, making it a target for suicide prevention. Recently, several studies have investigated neural pathways of NSSI using neuroimaging. However, there is a lack of systematized appraisal of these findings. This systematic review aims to identify and summarize the main neuroimaging findings of NSSI in youth. We followed PRISMA statement guidelines and searched MEDLINE, APA PsycInfo, and Google Scholar databases for neuroimaging studies, irrespective of imaging modality, specifically investigating NSSI in samples with a mean age of up to 25 years old. Quality assessment was made using the Newcastle–Ottawa and Joanna Briggs Institute scales. The initial search retrieved 3030 articles; 21 met inclusion criteria, with a total of 938 subjects. Eighteen studies employed functional neuroimaging techniques such as resting-state and task-based fMRI (emotional, interpersonal exposure/social exclusion, pain, reward, and cognitive processing paradigms). Three studies reported on structural MRI. An association of NSSI behavior and altered emotional processing in cortico-limbic neurocircuitry was commonly reported. Additionally, alterations in potential circuits involving pain, reward, interpersonal, self-processing, and executive function control processes were identified. NSSI has complex and diverse neural underpinnings. Future longitudinal studies are needed to understand its developmental aspects better.
Non-Coding RNAs and Splicing Activity in Testicular Germ Cell Tumors
Authors: Barchi Marco , Bielli Pamela , Dolci Susanna , Rossi Pellegrino , Grimaldi Paola
Published: July 2021

Testicular germ cell tumors (TGCTs) are the most common tumors in adolescent and young men. Recently, genome-wide studies have made it possible to progress in understanding the molecular mechanisms underlying the development of tumors. It is becoming increasingly clear that aberrant regulation of RNA metabolism can drive tumorigenesis and influence chemotherapeutic response. Notably, the expression of non-coding RNAs as well as specific splice variants is deeply deregulated in human cancers. Since these cancer-related RNA species are considered promising diagnostic, prognostic and therapeutic targets, understanding their function in cancer development is becoming a major challenge. Here, we summarize how the different expression of RNA species repertoire, including non-coding RNAs and protein-coding splicing variants, impacts on TGCTs’ onset and progression and sustains therapeutic resistance. Finally, the role of transcription-associated R-loop misregulation in the maintenance of genomic stability in TGCTs is also discussed.
Multimodal Patient-Specific Registration for Breast Imaging Using Biomechanical Modeling with Reference to AI Evaluation of Breast Tumor Change
Authors: Xue Cheng , Tang Fuk-Hay , Lai Christopher W. K. , Grimm Lars J. , Lo Joseph Y.
Published: July 2021

Background: The strategy to combat the problem associated with large deformations in the breast due to the difference in the medical imaging of patient posture plays a vital role in multimodal medical image registration with artificial intelligence (AI) initiatives. How to build a breast biomechanical model simulating the large-scale deformation of soft tissue remains a challenge but is highly desirable. Methods: This study proposed a hybrid individual-specific registration model of the breast combining finite element analysis, property optimization, and affine transformation to register breast images. During the registration process, the mechanical properties of the breast tissues were individually assigned using an optimization process, which allowed the model to become patient specific. Evaluation and results: The proposed method has been extensively tested on two datasets collected from two independent institutions, one from America and another from Hong Kong. Conclusions: Our method can accurately predict the deformation of breasts from the supine to prone position for both the Hong Kong and American samples, with a small target registration error of lesions.
Does Needle Design Affect the Regenerative Potential of Bone Marrow Aspirate? An In Vitro Study
Authors: Feddahi Nadia , Herten Monika , Tassemeier Tjark , Rekasi Heike , Hackel Alexander , Haversath Marcel , Jäger Marcus
Published: July 2021

While autologous bone is still the gold standard for treatment of bone defects, its availability is limited. Sufficient numbers of mesenchymal stroma cells (MSC) may be an alternative. Small volumes of bone marrow aspirate (BMA) were harvested with two different needle systems comparing the yield and regenerative potency of the MSCs. BMA (10 mL) was aspirated from the posterior iliac crest of 12 patients with degenerative spinal disc disease using both needle systems in each patient: the Jamshidi needle (JAM) and on the contralateral side the Marrow Cellution® Needle (AMC). Number of mononuclear cells (MNCs) and regeneration capacity (colony-forming unit/CFU) were determined. MSCs were characterized for surface markers and their differentiation into trilineages. There was no significant difference between the two harvesting needles regarding the quantity of MNCs in BMA: 5.2 ± 1.8 × 109 MNC/mL for AMC vs. 4.8 ± 2.5 × 109 MNC/mL for JAM, p = 0.182. The quantity of CFUs per ml BMA was similar for both groups: 3717 ± 5556 for AMC and 4305 ± 5507 for JAM (p = 0.695). The potency of MSCs expressed as colony-forming potential per 106 MNC resulted in 0.98 ± 1.51 for AMC and 1.00 ± 0.96 for JAM (p = 0.666). Regardless of the needle design, 10 mL bone marrow aspirate contains a sufficient number of about 40,000 MSCs that can be used to enhance bone healing.
4-Chloro-6-(chloromethyl)-1-methyl-1H-pyrazolo[3,4-d]pyrimidine
Authors: Ogurtsov Vladimir , Rakitin Oleg
Published: July 2021

A novel 4-chloro-6-(chloromethyl)-1-methyl-1H-pyrazolo[3,4-d]pyrimidine was prepared by a rational and short two-step synthesis from commercially available ethyl 5-amino-1-methyl-1H-pyrazole-4-carboxylate via 6-(chloromethyl)-1-methyl-1,5-dihydro-4H-pyrazolo[3,4-d]pyrimidin-4-one. The structure of the synthesized compounds was established by elemental analysis, high-resolution mass-spectrometry, 1H, 13C-NMR and IR spectroscopy and mass-spectrometry. 4-Chloro-6-(chloromethyl)-1-methyl-1H-pyrazolo[3,4-d]pyrimidine is a convenient intermediate for various disubstituted 1-methyl-1H-pyrazolo[3,4-d]pyrimidines, which may be of interest as substances with useful pharmacological properties.
9a-Phenyl-2,3,3a,3b,9a,9b-hexahydro-4H-furo[3‘,2’:3,4]cyclobuta- [1,2-b]chromen-4-one: A Flavone-Based [2 + 2]-Photocycloadduct
Authors: Lefarth Jens , Neudörfl Jörg , Griesbeck Axel G.
Published: July 2021

The intermolecular [2 + 2]-photocycloaddition of the parent flavone molecule (4) as the triplet energy-accepting species and the electron-rich alkene 2, 3-dihydrofuran (5) was performed by visible-light-mediated triplet-sensitization with an iridium-based organometallic sensitizer. The reaction proceeds with high diastereo- and regioselectivity (>98:2 for the regiochemical orientation and with 95% d.s.). In contrast to numerous other ene/enone combinations that are described in the literature and were also performed by us, the reaction between 4 and 5 almost solely afforded the cis-syn-cis cyclobutane 6, whereas analogous conjugated six- and five-membered cycloalkenones preferentially react to cis-anti-cis cyclobutanes or a mixture of both diastereoisomers (e.g., for the cyclohexanone-derived example 9).
A Novel Method for Harmonic Current Injection with Sensor Supported Adaptation on Permanent Magnet Synchronous Machines
Authors: Vollat Matthias , Krahe Dominik , Gauterin Frank
Published: July 2021

To reduce torque oscillations in electric motors, harmonic current injection (HCI) has been used in industry for some time. For this purpose, higher harmonic currents calculated in advance are injected into the machine. Since the general conditions for the machine can change during its life cycle, this article presents a method that makes it possible to change the parameters of HCI during operation. For this purpose, sensor signals are used to detect the reaction of the electric motor to small variations of the HCI parameters. The knowledge gained in this way is used to make further suitable variations. FEM simulations were used to verify the effectiveness of the approach. The results show that the algorithm can independently optimize the HCI parameters during runtime and reduces the amplitude of the 6th harmonic in the torque by 87% for a permanent magnet synchronous machine.
A Bender’s Algorithm of Decomposition Used for the Parallel Machine Problem of Robotic Cell
Authors: Komari Alaei Mohammad Reza , Soysal Mehmet , Elmi Atabak , Banaitis Audrius , Banaitiene Nerija , Rostamzadeh Reza , Javanmard Shima
Published: July 2021

The present research addresses the single transportation robot used to alleviate problems of robotic cell scheduling of the machines. For the purpose of minimizing the make-span, a model of mixed-integer linear programming (MILP) has been suggested. Since the inefficiency exists in NP-hard, a decomposition algorithm posed by Bender was utilized to alleviate the problem in real life situations. The proposed algorithm can be regarded as an efficient attempt to apply optimality Bender’s cuts regarding the problem of parallel machine robotic cell scheduling in order to reach precise resolutions for medium and big sized examples. The numerical analyses have demonstrated the efficiency of the proposed solving approach.
Transient Dynamic Analysis of Unconstrained Layer Damping Beams Characterized by a Fractional Derivative Model
Authors: Brun Mikel , Cortés Fernando , Elejabarrieta María Jesús
Published: July 2021

This paper presents a numerical analysis of the influence of mechanical properties and the thickness of viscoelastic materials on the transient dynamic behavior of free layer damping beams. Specifically, the beams consist of cantilever metal sheets with surface viscoelastic treatment, and two different configurations are analyzed: symmetric and asymmetric. The viscoelastic material is characterized by a five-parameter fractional derivative model, which requires specific numerical methods to solve for the transverse displacement of the free edge of the beam when a load is applied. Concretely, a homogenized finite element formulation is performed to reduce computation time, and the Newmark method is applied together with the Grünwald–Letnikov method to accomplish the time discretization of the fractional derivative equations. Amplitudes and response time are evaluated to study the transient dynamic behavior and results indicate that, in general, asymmetrical configurations present more vibration attenuation than the symmetrical ones. Additionally, it is deduced that a compromise between response time and amplitudes has to be reached, and in addition, the most influential parameters have been determined to achieve greater vibration reduction.
Characterizing Mathematics Learning in Colombian Higher Distance Education
Authors: Martinez-Villarraga Elizabeth , Lopez-Cobo Isabel , Becerra-Alonso David , Fernández-Navarro Francisco
Published: July 2021

The aim of this work is to characterize the process of constructing mathematical knowledge by higher education students in a distance learning course. This was done as part of an algebra course within engineering degrees in a Colombian university. The study used a Transformative Sequential Design in mixed methods research. The analysis also determined the kinds of mathematical knowledge attained by the students and its relationship to the Colombian social and cultural context. The students acquired declarative, procedural, and conditional knowledge, while the learning strategies were often superficial. In a context where power is distant, students take on a passive approach to learning despite being highly respectful towards the educator. Thus, the educational system has the educator at the center.
On State Occupancies, First Passage Times and Duration in Non-Homogeneous Semi-Markov Chains
Authors: Georgiou Andreas C. , Papadopoulou Alexandra , Kolias Pavlos , Palikrousis Haris , Farmakioti Evanthia
Published: July 2021

Semi-Markov processes generalize the Markov chains framework by utilizing abstract sojourn time distributions. They are widely known for offering enhanced accuracy in modeling stochastic phenomena. The aim of this paper is to provide closed analytic forms for three types of probabilities which describe attributes of considerable research interest in semi-Markov modeling: (a) the number of transitions to a state through time (Occupancy), (b) the number of transitions or the amount of time required to observe the first passage to a state (First passage time) and (c) the number of transitions or the amount of time required after a state is entered before the first real transition is made to another state (Duration). The non-homogeneous in time recursive relations of the above probabilities are developed and a description of the corresponding geometric transforms is produced. By applying appropriate properties, the closed analytic forms of the above probabilities are provided. Finally, data from human DNA sequences are used to illustrate the theoretical results of the paper.
Size Effects in Finite Element Modelling of 3D Printed Bone Scaffolds Using Hydroxyapatite PEOT/PBT Composites
Authors: Calderon-Uriszar-Aldaca Iñigo , Perez Sergio , Sinha Ravi , Camara-Torres Maria , Villanueva Sara , Mota Carlos , Patelli Alessandro , Matanza Amaia , Moroni Lorenzo , Sanchez Alberto
Published: July 2021

Additive manufacturing (AM) of scaffolds enables the fabrication of customized patient-specific implants for tissue regeneration. Scaffold customization does not involve only the macroscale shape of the final implant, but also their microscopic pore geometry and material properties, which are dependent on optimizable topology. A good match between the experimental data of AM scaffolds and the models is obtained when there is just a few millimetres at least in one direction. Here, we describe a methodology to perform finite element modelling on AM scaffolds for bone tissue regeneration with clinically relevant dimensions (i.e., volume > 1 cm3). The simulation used an equivalent cubic eight node finite elements mesh, and the materials properties were derived both empirically and numerically, from bulk material direct testing and simulated tests on scaffolds. The experimental validation was performed using poly(ethylene oxide terephthalate)-poly(butylene terephthalate) (PEOT/PBT) copolymers and 45 wt% nano hydroxyapatite fillers composites. By applying this methodology on three separate scaffold architectures with volumes larger than 1 cm3, the simulations overestimated the scaffold performance, resulting in 150–290% stiffer than average values obtained in the validation tests. The results mismatch highlighted the relevance of the lack of printing accuracy that is characteristic of the additive manufacturing process. Accordingly, a sensitivity analysis was performed on nine detected uncertainty sources, studying their influence. After the definition of acceptable execution tolerances and reliability levels, a design factor was defined to calibrate the methodology under expectable and conservative scenarios.
An Extension of Explicit Coupling for Fluid–Structure Interaction Problems
Authors: Bukač Martina
Published: July 2021

We present an extension of a non-iterative, partitioned method previously designed and used to model the interaction between an incompressible, viscous fluid and a thick elastic structure. The original method is based on the Robin boundary conditions and it features easy implementation and unconditional stability. However, it is sub-optimally accurate in time, yielding only O(Δt12) rate of convergence. In this work, we propose an extension of the method designed to improve the sub-optimal accuracy. We analyze the stability properties of the proposed method, showing that the method is stable under certain conditions. The accuracy and stability of the method are computationally investigated, showing a significant improvement in the accuracy when compared to the original scheme, and excellent stability properties. Furthermore, since the method depends on a combination parameter used in the Robin boundary conditions, whose values are problem specific, we suggest and investigate formulas according to which this parameter can be determined.
Power Spectral Density Analysis of Nanowire-Anchored Fluctuating Microbead Reveals a Double Lorentzian Distribution
Authors: Bánó Gregor , Kubacková Jana , Hovan Andrej , Strejčková Alena , Iványi Gergely T. , Vizsnyiczai Gaszton , Kelemen Lóránd , Žoldák Gabriel , Tomori Zoltán , Horvath Denis
Published: July 2021

In this work, we investigate the properties of a stochastic model, in which two coupled degrees of freedom are subordinated to viscous, elastic, and also additive random forces. Our model, which builds on previous progress in Brownian motion theory, is designed to describe water-immersed microparticles connected to a cantilever nanowire prepared by polymerization using two-photon direct laser writing (TPP-DLW). The model focuses on insights into nanowires exhibiting viscoelastic behavior, which defines the specific conditions of the microbead. The nanowire bending is described by a three-parameter linear model. The theoretical model is studied from the point of view of the power spectrum density of Brownian fluctuations. Our approach also focuses on the potential energy equipartition, which determines random forcing parametrization. Analytical calculations are provided that result in a double-Lorentzian power density spectrum with two corner frequencies. The proposed model explained our preliminary experimental findings as a result of the use of regression analysis. Furthermore, an a posteriori form of regression efficiency evaluation was designed and applied to three typical spectral regions. The agreement of respective moments obtained by integration of regressed dependences as well as by summing experimental data was confirmed.
On the Loop Homology of a Certain Complex of RNA Structures
Authors: Li Thomas J. X. , Reidys Christian M.
Published: July 2021

In this paper, we establish a topological framework of τ-structures to quantify the evolutionary transitions between two RNA sequence–structure pairs. τ-structures developed here consist of a pair of RNA secondary structures together with a non-crossing partial matching between the two backbones. The loop complex of a τ-structure captures the intersections of loops in both secondary structures. We compute the loop homology of τ-structures. We show that only the zeroth, first and second homology groups are free. In particular, we prove that the rank of the second homology group equals the number γ of certain arc-components in a τ-structure and that the rank of the first homology is given by γ−χ+1, where χ is the Euler characteristic of the loop complex.
A Revisited Conceptual Change in Mathematical-Physics Education from a Neurodidactic Approach: A Pendulum Inquiry
Authors: Ballesta-Claver Julio , Ayllón Blanco María Fernanda , Gómez Pérez Isabel Angustias
Published: July 2021

Learning physics today contains a strong algebraic component, which does not contribute to making an effective conceptual change due to several misunderstandings and misconceptions that students have. Inquiry-based science education methodology (IBSE) is a solution, as well as model-based inquiry (MBI), but no agreement exists regarding which one is the best option. The contribution of both new neuroscientific and cognitive psychology advances is necessary. All these components can be arranged within a transdisciplinary discipline called Neurodidactics. This work presents a neurodidactic proposal to achieve an effective conceptual change. The study involves 171 undergraduate university students and is based on an experimental design (control and experimental groups) with pre- and post-test questionnaires. Results will show the importance of experimentation in mathematical-physics sessions, as well as the importance of visuospatial abilities and the inquiry component offered by the different resources used (virtual simulations and multimedia) in order to obtain a model. In addition, the role of transdisciplinary orientation and the importance of conceptual modeling was tested, obtaining an essential contribution to balance the normally non-significant algebraic approach of physics science, offering altogether a possible new path for scientific learning.
A Multi-Objective Stochastic Solid Transportation Problem with the Supply, Demand, and Conveyance Capacity Following the Weibull Distribution
Authors: Das Amrit , Lee Gyu M.
Published: July 2021

This study addresses a multi-objective stochastic solid transportation problem (MOSSTP) with uncertainties in supply, demand, and conveyance capacity, following the Weibull distribution. This study aims to minimize multiple transportation costs in a solid transportation problem (STP) under probabilistic inequality constraints. The MOSSTP is expressed as a chance-constrained programming problem, and the probabilistic constraints are incorporated to ensure that the supply, demand, and conveyance capacity are satisfied with specified probabilities. The global criterion method and fuzzy goal programming approach have been used to solve multi-objective optimization problems. Computational results demonstrate the effectiveness of the proposed models and methodology for the MOSSTP under uncertainty. A sensitivity analysis is conducted to understand the sensitivity of parameters in the proposed model.
Trends in the Incidence of Acute Hepatitis B in the Polish Population and Their Determinants
Authors: Stawinska-Witoszynska Barbara , Klos Jan , Moryson Waclaw , Wieckowska Barbara
Published: July 2021

Introduction: The World Health Assembly adopted the Global Health Strategy and aims to reduce the incidence of Hepatitis from up to 10 million cases per year to 0.9 million cases and to reduce deaths from 1.4 million to 0.5 million per year by 2030. However, given the prevalence of chronic Hepatitis B in many countries and the incidence of new cases of acute Hepatitis B, the task is not easy. This study investigates the trends and determinants of the incidence of acute Hepatitis B in Poland in 2005–2019. Materials and Methods: Data on the incidence of acute hepatitis B (AHBV) were obtained from the National Institute of Public Health. A case definition for AHBV was consistent with the EU definition. The incidence trends were determined by considering the sex, age and place of residence. Due to the exponential dependence model, the computations were based on the logarithm of the incidence rate. This allowed for the transformation to linear form and analysis could be conducted using linear models. Pearson’s correlation was used to determine the linear trend of incidence in general and according to sex and place of residence. The values of incidence rates (independent proportions test) and the coefficients illustrating the trends under study were also compared among males and females as well as urban and rural residents. Results: The incidence of AHBV in the Polish population decreased with similar slopes in both sexes. The newly reported cases of AHBV were more frequent in the male population. The incidence of acute Hepatitis B in the urban population was significantly higher than in the rural population. The significant decreasing trends in incidence were observed in all age ranges, with the exception of two age ranges 0–4 and 10–14, where the total incidence during the whole study period was negligible. Conclusion: Despite the significant decrease in the incidence of AHBV in Poland and its position among the European countries with the lowest hepatitis B (HBV) incidence, the alarmingly high proportion of iatrogenic infections requires further improvement in the sanitary condition of health care facilities. It is also necessary to decrease the number of unvaccinated individuals.
Tobacco, Nicotine and Health
Authors: Neuberger Manfred
Published: July 2021

Recent studies have explored improvements in smoking prevention and cessation to reduce smoking prevalence, however, in Europe, only Finland has already set a date to become nicotine free. Studies reporting on central, eastern and southern Europe have mostly focused on combustible cigarettes up to now. In young people, correlations were found between traditional smoking, the “vaping” of e-cigarettes, experimentation with alcohol intoxication, and the use of illicit drugs. Prevention and cessation should include strategies against active and passive exposures to new nicotine products. This is a prerequisite for a successful public health policy and a future end-game against the business interests of the tobacco industry and its allies.
Shedding the Light on the Natural History of Intracranial Aneurysms: An Updated Overview
Authors: Giotta Lucifero Alice , Baldoncini Matías , Bruno Nunzio , Galzio Renato , Hernesniemi Juha , Luzzi Sabino
Published: July 2021

The exact molecular pathways underlying the multifactorial natural history of intracranial aneurysms (IAs) are still largely unknown, to the point that their understanding represents an imperative challenge in neurovascular research. Wall shear stress (WSS) promotes the genesis of IAs through an endothelial dysfunction causing an inflammatory cascade, vessel remodeling, phenotypic switching of the smooth muscle cells, and myointimal hyperplasia. Aneurysm growth is supported by endothelial oxidative stress and inflammatory mediators, whereas low and high WSS determine the rupture in sidewall and endwall IAs, respectively. Angioarchitecture, age older than 60 years, female gender, hypertension, cigarette smoking, alcohol abuse, and hypercholesterolemia also contribute to growth and rupture. The improvements of aneurysm wall imaging techniques and the implementation of target therapies targeted against inflammatory cascade may contribute to significantly modify the natural history of IAs. This narrative review strives to summarize the recent advances in the comprehension of the mechanisms underlying the genesis, growth, and rupture of IAs.
Comparison of G8 and ISAR Screening Results in Geriatric Urology
Authors: Bouzan Jobar , Stoilkov Boris , Nellas Spyridon , Horstmann Marcus
Published: July 2021

Background: The G8 and ISAR scores are two different screening tools for geriatric risk factors and frailty. The aim of this study was to compare the G8 and ISAR screening results in a cohort of urogeriatric patients to help clinicians to better understand and choose between the two tests. Methods: We retrospectively evaluated 100 patients at the age of 75 and above who were treated for different urological conditions. All routinely and prospectively underwent G8 and ISAR screening tests. A G8 score ≤ 14 and an ISAR score > 2 were considered positive. The results for the two tests were compared and correlated to clinical data. Results: The mean age of the patients was 83 y (min. 75–max. 101); 78 of the patients were male, while 22 were female; 58 of the patients were G8-positive, while 42 were G8-negative; and 24 were ISAR-positive, while 76 ISAR were negative. All the ISAR-positive patients were also G8-positive. There was a significant negative correlation between the G8 and ISAR scores (r = −0.77, p < 0.001). Both tests correlated significantly with the Charlson comorbidity index, length of stay, number of coded diagnosis, and Braden score (p < 0.05). Conclusion: Both tests are significantly correlated with each other and to clinical data related to geriatric frailty. However, the G8 score has a much higher rate of positive tests, which limits its use in daily routine, and the ISAR score is therefore preferable. For “fit” geriatric patients, however, a negative G8 score can be of great use as a confirmatory test for further decision making.
Resistance of Polypropylene Membrane to Oil Fouling during Membrane Distillation
Authors: Gryta Marek
Published: July 2021

The influence of oil emulsion presence in the water on the course of water desalination by membrane distillation was studied. The feed water was contaminated by oil collected from the bilge water. The impact of feed composition on the wetting resistance of hydrophobic polypropylene membranes was evaluated during long-term studies. Two types of the capillary membranes fabricated by thermally induced phase separation method were tested. It has been found that these membranes were non-wetted during the separation of NaCl solutions over a period of 500 h of modules exploitation. The addition of oil (5–100 mg/L) to the feed caused a progressive decline of the permeate flux up to 30%; however, the applied hydrophobic membranes retained their non-wettability for the consecutive 2400 h of the process operation. It was indicated that several compounds containing the carbonyl group were formed on the membranes surface during the process. These hydrophilic compounds facilitated the water adsorption on the surface of polypropylene which restricted the oil deposition on the membranes used.
Effect of Modifying the Membrane Surface with Microcapsules on the Flow Field for a Cross-Flow Membrane Setup: A CFD Study
Authors: Osterroth Sebastian , Neumann Christian , Weiß Michael , Maurieschat Uwe , Latnikova Alexandra , Rief Stefan
Published: July 2021

In this study, the attachment of microcapsules on the membrane surface and its influence on the flow field for a cross-flow membrane setup are investigated. The microcapsules were placed on the top layer of the membrane. The overall purpose of this modification was the prevention of membrane biofouling. Therefore, in a first step, the influence of such a combination on the fluid flow was investigated using computational fluid dynamics (CFD). Here, different properties, which are discussed as indicators for biofouling in the literature, were considered. In parallel, different fixation strategies for the microcapsules were experimentally tested. Two different methods to add the microcapsules were identified and further investigated. In the first method, the microcapsules are glued to the membrane surface, whereas in the second method, the microcapsules are added during the membrane fabrication. The different membrane modifications were studied and compared using CFD. Therefore, virtual geometries mimicking the real ones were created. An idealized virtual geometry was added to the comparison. Results from the simulation were fed back to the experiments to optimize the combined membrane. For the presented setup, it is shown that the glued configuration provides a lower transmembrane pressure than the configuration where microcapsules are added during fabrication.
Comparative Studies of Digestion Techniques for the Dissolution of Neodymium-Based Magnets
Authors: Bonin Mélodie , Fontaine Frédéric-Georges , Larivière Dominic
Published: July 2021

The digestion of neodymium (NdFeB) magnets was investigated in the context of recycling rare earth elements (i.e., Nd, Pr, Dy, and Tb). Among more conventional digestion techniques (microwave digestion, open vessel digestion, and alkaline fusion), focused infrared digestion (FID) was tested as a possible approach to rapidly and efficiently solubilize NdFeB magnets. FID parameters were initially optimized with unmagnetized magnet powder and subsequently used on magnet pieces, demonstrating that the demagnetization and grinding steps are optional.
Application of Machine Learning Algorithms and SHAP for Prediction and Feature Analysis of Tempered Martensite Hardness in Low-Alloy Steels
Authors: Jeon Junhyub , Seo Namhyuk , Son Seung Bae , Lee Seok-Jae , Jung Minsu
Published: July 2021

The tempering of low-alloy steels is important for controlling the mechanical properties required for industrial fields. Several studies have investigated the relationships between the input and target values of materials using machine learning algorithms. The limitation of machine learning algorithms is that the mechanism of how the input values affect the output has yet to be confirmed despite numerous case studies. To address this issue, we trained four machine learning algorithms to control the hardness of low-alloy steels under various tempering conditions. The models were trained using the tempering temperature, holding time, and composition of the alloy as the inputs. The input data were drawn from a database of more than 1900 experimental datasets for low-alloy steels created from the relevant literature. We selected the random forest regression (RFR) model to analyze its mechanism and the importance of the input values using Shapley additive explanations (SHAP). The prediction accuracy of the RFR for the tempered martensite hardness was better than that of the empirical equation. The tempering temperature is the most important feature for controlling the hardness, followed by the C content, the holding time, and the Cr, Si, Mn, Mo, and Ni contents.
Using SKPFM to Determine the Influence of Deformation-Induced Dislocations on the Volta Potential of Copper
Authors: Zhang Yang , Shi Wei , Xiang Song
Published: July 2021

The variation rule of the Volta potential on deformed copper surfaces with the dislocation density is determined in this study by using electron back-scattered diffraction (EBSD) in conjunction with scanning Kelvin probe force microscopy (SKPFM). The results show that the Volta potential is not linear in the dislocation density. When the dislocation density increases due to the deformation of pure copper, the Volta potential tends to a physical limit. The Volta potential exhibits a fractional function relationship with the dislocation density only for a relatively low shape variable.
Heat Treatment of Steels
Authors: Di Schino Andrea , Testani Claudio
Published: July 2021

Steels represent an interesting family of materials, both from a scientific and commercial point of view, considering the many innovative applications they can be used for [...]
Influence of Processing Route on the Surface Reactivity of Cu47Ti33Zr11Ni6Sn2Si1 Metallic Glass
Authors: Soares Barreto Erika , Uhlenwinkel Volker , Frey Maximilian , Gallino Isabella , Busch Ralf , Lüttge Andreas
Published: July 2021

Recently, laser additive manufacturing (AM) techniques have emerged as a promising alternative for the synthesis of bulk metallic glasses (BMGs) with massively increased freedom in part size and geometry, thus extending their economic applicability of this material class. Nevertheless, porosity, compositional inhomogeneity, and crystallization display themselves to be the emerging challenges for this processing route. The impact of these “defects” on the surface reactivity and susceptibility to corrosion was seldom investigated but is critical for the further development of 3D-printed BMGs. This work compares the surface reactivity of cast and additively manufactured (via laser powder bed fusion—LPBF) Cu47Ti33Zr11Ni6Sn2Si1 metallic glass after 21 days of immersion in a corrosive HCl solution. The cast material presents lower oxygen content, homogeneous chemical distribution of the main elements, and the surface remains unaffected after the corrosion experimentation based on vertical scanning interferometry (VSI) investigation. On the contrary, the LPBF material presents a considerably higher reactivity seen through crack propagations on the surface. It exhibits higher oxygen content, heterogeneous chemical distribution, and presence of defects (porosity and cracks) generated during the manufacturing process.
Numerical Analysis on Characteristics of Reduction Process within a Pre-Reduction Rotary Kiln
Authors: Liu Chenghong , Ding Xueyong , Liu Hegong , Yan Xinlin , Dong Chao , Wang Jia
Published: July 2021

The reduction process inside the ore pre-reduction rotary kiln involves a series of physicochemical reactions, and in-depth understanding of the reduction behavior is helpful to improve the product quality and productivity. This paper reports a three-dimensional steady state mathematical model based on computational fluid dynamics, which considers heat transfer, mass transfer and chemical reactions inside the rotary kiln. A user-defined functions (UDFs) program in C language is developed to define physical parameters and chemical reactions, and calculate the heat and mass transfer between freeboard and bed regions. The model is validated by measurement data and is then used to investigate the detailed information inside the rotary kiln. The results show that there is a temperature gradient in the bed, which is maximal near the kiln tail and decreases gradually as the reduction process progresses. The result also confirms that the reduction of FeO to Fe is the limiting step of the whole reduction process because this reaction requires a higher reduction potential. Furthermore, the influence of C/O mole ratio and fill degree are analyzed by comparing the average bed temperature, reduction potential and metallization ratio.
A Single LC-MS/MS Analysis to Quantify CoA Biosynthetic Intermediates and Short-Chain Acyl CoAs
Authors: Jones Anthony E. , Arias Nataly J. , Acevedo Aracely , Reddy Srinivasa T. , Divakaruni Ajit S. , Meriwether David
Published: July 2021

Coenzyme A (CoA) is an essential cofactor for dozens of reactions in intermediary metabolism. Dysregulation of CoA synthesis or acyl CoA metabolism can result in metabolic or neurodegenerative disease. Although several methods use liquid chromatography coupled with mass spectrometry/mass spectrometry (LC-MS/MS) to quantify acyl CoA levels in biological samples, few allow for simultaneous measurement of intermediates in the CoA biosynthetic pathway. Here we describe a simple sample preparation and LC-MS/MS method that can measure both short-chain acyl CoAs and biosynthetic precursors of CoA. The method does not require use of a solid phase extraction column during sample preparation and exhibits high sensitivity, precision, and accuracy. It reproduces expected changes from known effectors of cellular CoA homeostasis and helps clarify the mechanism by which excess concentrations of etomoxir reduce intracellular CoA levels.
Metagenomic, Metabolomic, and Functional Evaluation of Kimchi Broth Treated with Light-Emitting Diodes (LEDs)
Authors: Oh Yeong-Ji , Park Ye-Rin , Hong Jungil , Lee Do-Yup
Published: July 2021

The light-emitting diode (LED) has been widely used in the food industry, and its application has been focused on microbial sterilization, specifically using blue-LED. The investigation has been recently extended to characterize the biotic and abiotic (photodynamic) effects of different wavelengths. Here, we investigated LED effects on kimchi fermentation. Kimchi broths were treated with three different colored-LEDs (red, green, and blue) or kept in the dark as a control. Multiomics was applied to evaluate the microbial taxonomic composition using 16S rRNA gene amplicon sequencing, and the metabolomic profiles were determined using liquid chromatography–Orbitrap mass spectrometry. Cell viability was tested to determine the potential cytotoxicity of the LED-treated kimchi broths. First, the amplicon sequencing data showed substantial changes in taxonomic composition at the family and genus levels according to incubation (initial condition vs. all other groups). The differences among the treated groups (red-LED (RLED), green-LED (GLED), blue-LED (BLED), and dark condition) were marginal. The relative abundance of Weissella was decreased in all treated groups compared to that of the initial condition, which coincided with the decreased composition of Lactobacillus. Compositional changes were relatively high in the GLED group. Subsequent metabolomic analysis indicated a unique metabolic phenotype instigated by different LED treatments, which led to the identification of the LED treatment-specific and common compounds (e.g., luteolin, 6-methylquinoline, 2-hydroxycinnamic acid, and 9-HODE). These results indicate that different LED wavelengths induce characteristic alterations in the microbial composition and metabolomic content, which may have applications in food processing and storage with the aim of improving nutritional quality and the safety of food.
Embedding of Ultrathin Chips in Highly Flexible, Photosensitive Solder Mask Resist
Authors: Janek Florian , Eichhorn Nadine , Weser Sascha , Gläser Kerstin , Eberhardt Wolfgang , Zimmermann André
Published: July 2021

This work presents an embedding process for ultrathin silicon chips in mechanically flexible solder mask resist and their electrical contacting by inkjet printing. Photosensitive solder mask resist is applied by conformal spray coating onto epoxy bonded ultrathin chips with a daisy chain layout. The contact pads are opened by photolithography using UV direct light exposure. Circular and rectangular openings of 90 µm and 130 µm diameter, respectively, edge length are realized. Commercial inks containing nanoparticular silver and gold are inkjet printed to form conductive tracks between daisy chain structures. Different numbers of ink layers are applied. The track resistances are characterized by needle probing. Silver ink shows low resistances only for multiple layers and 90 µm openings, while gold ink exhibits low resistances in the single-digit Ω-range for minimum two printed layers.
An Energy Efficient Thermally Regulated Optical Spectroscopy Cell for Lab-on-Chip Devices: Applied to Nitrate Detection
Authors: Murphy Benjamin J. , Luy Edward A. , Panzica Katerina L. , Johnson Gregory , Sieben Vincent J.
Published: July 2021

Reagent-based colorimetric analyzers often heat the fluid under analysis for improved reaction kinetics, whilst also aiming to minimize energy use per measurement. Here, a novel method of conserving heat energy on such microfluidic systems is presented. Our design reduces heat transfer to the environment by surrounding the heated optical cell on four sides with integral air pockets, thereby realizing an insulated and suspended bridge structure. Our design was simulated in COMSOL Multiphysics and verified in a polymethyl methacrylate (PMMA) device. We evaluate the effectiveness of the insulated design by comparing it to a non-insulated cell. For temperatures up to 55 °C, the average power consumption was reduced by 49.3% in the simulation and 40.2% in the experiment. The designs were then characterized with the vanadium and Griess reagent assay for nitrate at 35 °C. Nitrate concentrations from 0.25 µM to 50 µM were tested and yielded the expected linear relationship with a limit of detection of 20 nM. We show a reduction in energy consumption from 195 J to 119 J per 10 min measurement using only 4 µL of fluid. Efficient heating on-chip will have broad applicability to numerous colorimetric assays.