bluuebunny/crossref_metadata_2025 huggingface dataset:
Verification of a Body Freedom Flutter Numerical Simulation Method Based on Main Influence Parameters
Authors: Lei Pengxuan , Guo Hongtao , LYu Binbin , Chen Dehua , Yu Li
Published: October 2021

The body freedom flutter characteristics of an airfoil and a fly wing aircraft model were calculated based on a CFD method for the Navier–Stokes equations. Firstly, a rigid elastic coupling dynamic model of a two-dimensional airfoil with a free–free boundary condition was derived in an inertial frame and decoupled by rigid body mode and elastic mode. In the fluid–solid coupling method, the rigid body was trimmed by subtracting the generalized steady aerodynamic force from the structural dynamic equation. The flutter characteristics were predicted by the variable stiffness method at a fixed Mach number and flight altitude. Finally, validation of the predicted body freedom flutter characteristics was performed through a comparison of theoretical solutions based on a Theodorsen unsteady aerodynamic model for airfoil and experimental results for a fly wing aircraft model. The mechanism of the influence of the bending mode stiffness and the position of the center of gravity on the body freedom flutter characteristics were briefly analyzed.
Pricing and Channel Coordination in Online-to-Offline Supply Chain Considering Corporate Environmental Responsibility and Lateral Inventory Transshipment
Authors: Cao Bingbing , You Tianhui , Liu Chunyi , Zhao Jian
Published: October 2021

In this study, we investigate pricing policy and coordination conditions in an online-to-offline supply chain considering corporate environmental responsibility and lateral inventory transshipment. First, we provide demand functions to capture effects of price, corporate environmental responsibility level, and preference degree of the consumer to online channel. Then, we build profit functions and develop three joint pricing and corporate environmental responsibility-level decision models for centralized decision (Scenario CD), retailer Stackelberg game (Scenario RS), and manufacturer Stackelberg game (Scenario MS). Furthermore, we determine the optimal decision policies by solving developed models, and conduct sensitivity analysis of significant factors. Finally, we use a revenue-sharing contract to realize supply chain coordination and find coordination conditions for Scenario RS and MS, and further show the impacts of revenue-sharing rate and investment cost sensitivity on the conditions using numerical studies. We find that optimal joint decision policies can be affected by significant factors to a varying degree. In certain conditions, the revenue-sharing contract can coordinate online-to-offline supply chains considering corporate environmental responsibility and lateral inventory transshipment. Our study proposes a new decision problem, constructs new joint decision models, determines new optimal joint policies, conducts new coordination analysis, and thus contributes to the research on supply chain operations considering corporate environmental responsibility and lateral inventory transshipment.
Algorithmic Analysis of Finite-Source Multi-Server Heterogeneous Queueing Systems
Authors: Efrosinin Dmitry , Stepanova Natalia , Sztrik Janos
Published: October 2021

The paper deals with a finite-source queueing system serving one class of customers and consisting of heterogeneous servers with unequal service intensities and of one common queue. The main model has a non-preemptive service when the customer can not change the server during its service time. The optimal allocation problem is formulated as a Markov-decision one. We show numerically that the optimal policy which minimizes the long-run average number of customers in the system has a threshold structure. We derive the matrix expressions for performance measures of the system and compare the main model with alternative simplified queuing systems which are analysed for the arbitrary number of servers. We observe that the preemptive heterogeneous model operating under a threshold policy is a good approximation for the main model by calculating the mean number of customers in the system. Moreover, using the preemptive and non-preemptive queueing models with the faster server first policy the lower and upper bounds are calculated for this mean value.
A Reverse Non-Stationary Generalized B-Splines Subdivision Scheme
Authors: Lamnii Abdellah , Nour Mohamed Yassir , Zidna Ahmed
Published: October 2021

In this paper, two new families of non-stationary subdivision schemes are introduced. The schemes are constructed from uniform generalized B-splines with multiple knots of orders 3 and 4, respectively. Then, we construct a third-order reverse subdivision framework. For that, we derive a generalized multi-resolution mask based on their third-order subdivision filters. For the reverse of the fourth-order scheme, two methods are used; the first one is based on least-squares formulation and the second one is based on solving a linear optimization problem. Numerical examples are given to show the performance of the new schemes in reproducing different shapes of initial control polygons.
Extended Kung–Traub Methods for Solving Equations with Applications
Authors: Regmi Samundra , Argyros Ioannis K. , George Santhosh , Magreñán Ángel Alberto , Argyros Michael I.
Published: October 2021

Kung and Traub (1974) proposed an iterative method for solving equations defined on the real line. The convergence order four was shown using Taylor expansions, requiring the existence of the fifth derivative not in this method. However, these hypotheses limit the utilization of it to functions that are at least five times differentiable, although the methods may converge. As far as we know, no semi-local convergence has been given in this setting. Our goal is to extend the applicability of this method in both the local and semi-local convergence case and in the more general setting of Banach space valued operators. Moreover, we use our idea of recurrent functions and conditions only on the first derivative and divided difference, which appear in the method. This idea can be used to extend other high convergence multipoint and multistep methods. Numerical experiments testing the convergence criteria complement this study.
Study on the Mechanism of the Blood-Glucose-Lowering Effect of Collagen Peptides from Sturgeon By-Products
Authors: Sasaoka Yukiho , Takagi Taichi , Michiba Shunta , Yamamoto Yohei , Kumagai Yuya , Kishimura Hideki
Published: October 2021

In a previous study, we found that the collagen peptides prepared from the by-products of Bester sturgeon had an inhibitory effect on elevated blood glucose levels in a glucose tolerance test with ICR mice. In the present study, we examine the mechanism of the effect of sturgeon collagen peptides (SCPs) in detail. When glucose was orally administered to mice along with the SCPs, it was found that the glucose remained in the stomach for a longer time. In the above tests, the amount of glucose excreted in the feces of mice also increased. On the contrary, it was revealed that the SCPs have a dipeptidyl-peptidase-IV (DPP-IV) inhibitory ability in an in vitro test. In subsequent oral and intravenous glucose administration tests, glucagon-like peptide-1 (GLP-1) and insulin levels in the blood of mice were maintained at high levels. These results suggested the following three mechanisms: SCPs slow the rate of transportation of glucose from the stomach into the small intestine, resulting in delayed glucose absorption; SCPs suppress the absorption of glucose in the small intestine and excrete it from the body; SCPs inhibit DPP-IV in the blood and maintain a high GLP-1 level in blood, which in turn stimulates insulin secretion.
A Rare Evolution to Pneumopericardium in Patient with COVID-19 Pneumonia Treated with High Flow Nasal Cannula
Authors: Polistina Giorgio Emanuele , Lanza Maurizia , Di Somma Camilla Di , Annunziata Anna , Fiorentino Giuseppe
Published: October 2021

Infection with severe acute respiratory syndrome coronavirus 2 causes coronavirus disease 2019 (COVID-19) which was revealed an official pandemic by the World Health Organization on 11 March 2020. The current pandemic, the third of this decade, is the worst in terms of suffering and deaths related. COVID-19 represents an unprecedented challenge for medical communities and patients around the world. High-resolution computed tomography of the chest (HRCT) is a fundamental tool in both management and diagnosis of the disease. Imaging plays an essential role in the diagnosis of all the manifestations of the disease and its complications and the correct use and interpretation of imaging tests are essential. Pneumomediastinum has been reported rarely in COVID-19 patients. We were one of the first groups to share our experiences in uncommon parenchymal complications of COVID-19 with spontaneous pneumothorax and pneumomediastinum, but also with new-onset bronchiectasis and cysts. A finding of pneumopericardium is also unusual. We hereby report a rare case of spontaneous pneumopericardium in a patient with COVID-19 pneumonia treated only with a high-flow nasal cannula (HFNC).
Long-Term Pain Characteristics and Management Following Minimally Invasive Spinal Decompression and Open Laminectomy and Fusion for Spinal Stenosis
Authors: Regev Gilad J. , Leor Gil , Ankori Ran , Hochberg Uri , Ofir Dror , Khashan Morsi , Kedem Ron , Lidar Zvi , Salame Khalil
Published: October 2021

Background and Objectives: To compare the long-term pain characteristics and its chronic management following minimally invasive spinal (MIS) decompression and open laminectomy with fusion for lumbar stenosis. Materials and Methods: The study cohort included patients with a minimum 5-year postoperative follow-up after undergoing either MIS decompression or laminectomy with fusion for spinal claudication. The primary outcome of interest was chronic back and leg pain intensity. Secondary outcome measures included pain frequency during the day, chronic use of non-opioid analgesics, narcotic medications, medical cannabinoids, and continuous interventional pain treatments. Results: A total of 95 patients with lumbar spinal stenosis underwent one- or two-level surgery for lumbar spinal stenosis between April 2009 and July 2013. Of these, 50 patients underwent MIS decompression and 45 patients underwent open laminectomy with instrumented fusion. In the fusion group, a higher percentage of patients experienced moderate-to-severe back pain with 48% compared to 21.8% of patients in the MIS decompression group (p < 0.01). In contrast, we found no significant difference in the reported leg pain in both groups. In the fusion group, 20% of the patients described their back and leg pain as persistent throughout the day compared to only 2.2% in the MIS decompression group (p < 0.05). A trend toward higher chronic dependence on analgesic medication and repetitive pain clinic treatments was found in the fusion group. Conclusions: MIS decompression for the treatment of degenerative spinal stenosis resulted in decreased long-term back pain and similar leg pain outcomes compared to open laminectomy and instrumented fusion surgery.
Bilateral Proximal Tibiofibular Synostosis Caused by Osteochondroma in a 21-Year-Old Highly Active Male—First in Literature
Authors: Pisecky Lorenz , Großbötzl Gerhard , Stevoska Stella , Stadler Christian , Ziernhöld Maximilian , Noack Petar , Gotterbarm Tobias , Luger Matthias
Published: October 2021

Background and Objectives: Up until now, only one case of unilateral proximal tibiofibular synostosis caused by osteochondroma has been reported. This report is the first well-documented bilateral case of proximal tibiofibular synostosis caused by an osteochondroma. Case Report: A 21-year-old, highly active male patient with bilateral proximal tibiofibular synostosis caused by an osteochondroma suffering from persistent knee pain is presented. As conservative methods had failed, the patient was treated by bilateral open resection of the connecting bone. Histopathological findings confirmed the preoperative diagnosis. The patient returned to sports three weeks after surgery and continued soccer training six weeks after surgery. Discussion: The case report presents the successful treatment of a bilateral proximal tibiofibular synostosis caused by an osteochondroma by bilateral open resection of the connecting bone.
Gastrodia elata Blume and Zanthoxylum schinifolium Siebold & Zucc Mixed Extract Suppress Platelet Aggregation and Thrombosis
Authors: Jeon Yong-Deok , Lee Ji-Hyun , Park Mi-Ran , Lim Ji-Ye , Kang Sa-Haeng , Kim Dae-Ki , Lee Young-Mi
Published: October 2021

Background and objectives: Blood vessel thrombosis causes blood circulation disorders, leading to various diseases. Currently, various antiplatelet and anticoagulant drugs, such as aspirin, warfarin, heparin, and non-vitamin K antagonist oral anticoagulants (NOACs), are used as the major drugs for the treatment of a wide range of thrombosis. However, these drugs have a side effect of possibly causing internal bleeding due to poor hemostasis when taken for a long period of time. Materials and Methods: Gastrodia elata Blume (GE) and Zanthoxylum schinifolium Siebold & Zucc (ZS) are known to exhibit hemostatic and antiplatelet effects as traditional medicines that have been used for a long time. In this study, we investigated the effect of a mixed extract of GE and ZS (MJGE09) on platelet aggregation and plasma coagulation. Results: We found that MJGE09 inhibited collagen-and ADP-induced platelet aggregation in vitro. In addition, collagen- and ADP-induced platelet aggregation were also inhibited in a dose-dependent manner on the platelets of mice that were orally administered MJGE09 ex vivo. However, compared with aspirin, MJGE09 did not prolong the rat tail vein bleeding time in vivo and did not show a significant effect on the increase in the prothrombin time (PT) and activated partial thromboplastin time (aPTT). Conclusions: These results suggest that MJGE09 can be used as a potential anticoagulant with improved antithrombotic efficacy.
The Role of Bradykinin Receptors in the Etiopathogenesis of Chronic Spontaneous Urticaria
Authors: Obtulowicz Aleksander , Dubiela Pawel , Dyga Wojciech , Migacz-Gruszka Kamila , Mikolajczyk Tomasz , Wojas-Pelc Anna , Obtulowicz Krystyna
Published: October 2021

Background and Objectives: Chronic spontaneous urticaria (CSU) is a distressing skin condition, which manifests as red, swollen, itchy, and sometimes painful hives or wheals appearing on skin. Recently, CSU has been associated with bradykinin release, which was previously discovered to be the main trigger of hereditary angioedema attacks. To study the role of bradykinin receptors 1 (BR1) and 2 (BR2) in the etiopathogenesis of CSU. Materials and Methods: A total of 60 individuals, 30 patients with CSU and 30 healthy subjects, were recruited to the study. CSU was diagnosed in accordance with the standardized protocol of dermatological assessment of skin symptoms. The level of bradykinin receptors was determined in populations of CD3+, CD4+, and CD8+ lymphocytes as well as in CD14++CD16−, CD14++CD16+ and CD14+CD16+ monocytes. In addition, urticaria activity score summed over 7 days (UAS-7) was assessed and correlated with BR1 and BR2 expression. Results: A statistically significant higher concentration of BR1 expression in lymphocytes was found in patients with CSU, compared to the control group (p < 0.001). Moreover, a statistically significant positive correlation was observed between UAS-7 and BR1/BR2 expression in CD14++CD16− cells (p = 0.03, R = 0.4). Conclusions: Bradykinin receptors are elevated in selected populations of lymphocytes in symptomatic CSU patients compared to healthy controls, indicating their role in the etiopathogenesis of the disease.
Laparoscopy in Gynecologic and Abdominal Surgery in Regional (Spinal, Peridural) Anesthesia, the Utility of the Technique during COVID-19 Pandemic
Authors: Major Attila Louis , Jumaniyazov Kudrat , Yusupova Shahnoza , Jabbarov Ruslan , Saidmamatov Olimjon , Mayboroda-Major Ivanna
Published: October 2021

Background: laparoscopic surgery is mainly performed in general anesthesia. Symptomatic patients infected with COVID-19 needing surgery are however at higher risk for COVID-19 complications in general anesthesia than in regional anesthesia. Even so, Covid transfection is a hazard to medical personnel during the intubation procedure and treatment drugs may be in shortage during a pandemic. Recovery and hospital stay are also shorter after laparoscopy. Laparoscopy performed in regional anesthesia may have several advantages in limiting Covid. Methods: international literature on the risk of COVID-19 complications development was searched. 3 topics concerning laparoscopic surgery were reviewed: (1) Achievements in laparoscopy; (2) Advantages of regional anesthesia compared to general anesthesia; (3) Feasibility to perform laparoscopy in regional anesthesia in COVID-19 pandemic. The authors reviewed abstracts and full-text articles concerning laparoscopic surgery, gynecology, anesthesia and COVID-19. Studies published in PubMed, Embase, Cochrane Library and found in Google Scholar before 1st FEB, 2021 were retrieved and analyzed. Results: a total of 83 studies were found, all of them written in English. 17 studies could be found in gynecology and in general surgery about laparoscopy with regional anesthesia. In Covid time only one study compared laparoscopic surgery in general anesthesia to laparotomy and another study laparotomy in general anesthesia to regional anesthesia. Laparoscopy showed no disadvantage compared to laparotomy in Covid pandemic and in another study laparotomy in general anesthesia was associated with higher mortality and more pulmonary complications. Trendelenburg position can be a threat if used by inexperienced personnel and can induce unintended anesthesia of breathing organs. On the other hand Trendelenburg position has advantages for cardiovascular and pulmonary functions. Pneumoperitoneum of low CO2 pressure is well tolerated by patients. Conclusions: elective surgery should be postponed in symptomatic Covid patients. In inevitable emergency surgery intubation anesthesia in COVID-19 pandemic is as far as possible to be avoided. In COVID-19 pandemic, regional anesthesia is the preferred choice. The optimum may be the combination of laparoscopic surgery with regional anesthesia. Reducing the pneumoperitoneum is a good compromise for the comfort of patients and surgeons. A special case is gynecology, which needs to be performed in Trendelenburg position to free pelvic organs.
Microstructural Evolution as a Function of Increasing Aluminum Content in Novel Lightweight Cast Irons
Authors: Obregon Alejandro , Sanchez Jon Mikel , Eguizabal David , Garcia Jose Carlos , Arruebarrena Gurutze , Hurtado Iñaki , Quintana Ion , Rodriguez Patxi
Published: October 2021

In the context of the development of new lightweight materials, Al-alloyed cast irons have a great potential for reducing the weight of the different part of the vehicles in the transport industry. The correlation of the amount of Al and its effect in the microstructure of cast irons is not completely well established as it is affected by many factors such as chemical composition, cooling rate, etc. In this work, four novel lightweight cast irons were developed with different amounts of Al (from 0 wt. % to 15 wt. %). The alloys were manufactured by an easily scalable and affordable gravity casting process in an induction furnace, and casted in a resin-bonded sand mold. The microstructural evolution as a function of increasing Al content by different microstructural characterization techniques was studied. The hardness of the cast irons was measured by the Vickers indentation test and correlated with the previously characterized microstructures. In general, the microstructural evolution shows that the perlite content decrease with the increment of wt. % of Al. The opposite occurs with the ferrite content. In the case of graphite, a slight increment occurs with 2 wt. % of Al, but a great decrease occurs until 15 wt. % of Al. The addition of Al promotes the stabilization of ferrite in the studied alloys. The hardness obtained varied from 235 HV and 363 HV in function of the Al content. The addition of Al increases the hardness of the studied cast irons, but not gradually. The alloy with the highest hardness is the alloy containing 7 wt. % Al, which is correlated with the formation of kappa-carbides and finer perlite.
Effects of Ce-Rich Misch Metal on the Microstructures and Tensile Properties of as-Cast Mg-7Al-3Sn-1Zn Alloys
Authors: Liu Guo-Jun , Sun Yan-Hua , Xia Nan , Guan Xiao-Fang
Published: October 2021

The effects of small amounts of Ce-rich misch metal (Mm: 0.5, 1.0 and 2.0 wt.%) addition on the microstructure and tensile properties of as-cast Mg-7Al-3Sn-1Zn wt.% (ATZ731) alloy have been investigated. The addition of Mm restricts the formation of the Mg17Al12 phase but greatly promotes the Al4Mm phase. The proper Mm addition enhances the strength and ductility of ATZ731 alloys at both room temperature (RT) and 175 °C. ATZ731 alloys with 1.0 wt.% Mm addition exhibit an advantageous combination strength and ductility, with the ultimate tensile strength (UTS), 0.2% yield strength (YS) and elongation to failure (Ef) at 175 °C of ~148 MPa, ~102 MPa and ~28%, improved by ~14.7%, ~24.3% and ~53.8%, respectively, compared to those of ATZ731 alloy. This enhancement is primarily owing to the refined microstructures and the high thermal stability of Al4Mm at the elevated temperature in contrast with that of the Mg17Al12 phase. The fracture modes are also discussed.
Numerical Analysis of Friction Effects on Temperature and Phases within Forged Ti-6Al-4V Alloy Aeroengine Drum
Authors: Luo Shiyuan , Jiang Yongxin , Yan Kai , Zou Guangming , Zhang Po , Yu Fengping
Published: October 2021

Friction conditions significantly impact the temperature and phases of titanium forged parts, further directly affecting the microstructures and mechanical properties of final parts. In this paper, a 2D simplified finite element (FE) model combined with phase transition equations is developed to simulate a Ti-6Al-4V drum forging procedure. Then, friction effects on the temperature and phases of the forged drum are numerically analyzed and verified by experiments. The simulated results indicate that a reasonable range of friction factor is needed to obtain a relatively homogenous temperature distribution within the forged drum. Moreover, unlike its small influence on the α + β phase, improving friction obviously decreases the general levels of temperature and β phase and increases the homogeneities of α and β phases within the forged drum, which are associated with cooling rates and the heating effects of friction and deformation.
Fatigue Crack Growth Behaviour and Role of Roughness-Induced Crack Closure in CP Ti: Stress Amplitude Dependence
Authors: Ahmed Mansur , Islam Md. Saiful , Yin Shuo , Coull Richard , Rozumek Dariusz
Published: October 2021

This paper investigated the fatigue crack propagation mechanism of CP Ti at various stress amplitudes (175, 200, 227 MPa). One single crack at 175 MPa and three main cracks via sub-crack coalescence at 227 MPa were found to be responsible for fatigue failure. Crack deflection and crack branching that cause roughness-induced crack closure (RICC) appeared at all studied stress amplitudes; hence, RICC at various stages of crack propagation (100, 300 and 500 µm) could be quantitatively calculated. Noticeably, a lower RICC at higher stress amplitudes (227 MPa) for fatigue cracks longer than 100 µm was found than for those at 175 MPa. This caused the variation in crack growth rates in the studied conditions.
Experimental and Numerical Analysis on TIG Arc Welding of Stainless Steel Using RSM Approach
Authors: Sattarpanah Karganroudi Sasan , Moradi Mahmoud , Aghaee Attar Milad , Rasouli Seyed Alireza , Ghoreishi Majid , Lawrence Jonathan , Ibrahim Hussein
Published: October 2021

This study involves the validating of thermal analysis during TIG Arc welding of 1.4418 steel using finite element analyses (FEA) with experimental approaches. 3D heat transfer simulation of 1.4418 stainless steel TIG arc welding is implemented using ABAQUS software (6.14, ABAQUS Inc., Johnston, RI, USA), based on non-uniform Goldak’s Gaussian heat flux distribution, using additional DFLUX subroutine written in the FORTRAN (Formula Translation). The influences of the arc current and welding speed on the heat flux density, weld bead geometry, and temperature distribution at the transverse direction are analyzed by response surface methodology (RSM). Validating numerical simulation with experimental dimensions of weld bead geometry consists of width and depth of penetration with an average of 10% deviation has been performed. Results reveal that the suggested numerical model would be appropriate for the TIG arc welding process. According to the results, as the welding speed increases, the residence time of arc shortens correspondingly, bead width and depth of penetration decrease subsequently, whilst simultaneously, the current has the reverse effect. Finally, multi-objective optimization of the process is applied by Derringer’s desirability technique to achieve the proper weld. The optimum condition is obtained with 2.7 mm/s scanning speed and 120 A current to achieve full penetration weld with minimum fusion zone (FZ) and heat-affected zone (HAZ) width.
Property Improvement of Additively Manufactured Ti64 by Heat Treatment Characterized by In Situ High Temperature EBSD and Neutron Diffraction
Authors: Takajo Shigehiro , Tomida Toshiro , Caspi El’ad N. , Pesach Asaf , Tiferet Eitan , Vogel Sven C.
Published: October 2021

Among various off-equilibrium microstructures of additively manufactured Ti-6Al-4V alloy, electron beam powder bed fusion, in which three dimensional metallic objects are fabricated by melting the ingredient powder materials layer by layer on a pre-heated bed, results in a specimen that is nearly free of the preferred orientation of the α-Ti phase as well as a low beta phase fraction of ~1 wt%. However, when further heat treatment of up to 1050 °C was applied to the material in our previous study, a strong texture aligning the hexagonal basal plane of α phase with the build direction and about 6% β phase appeared at room temperature. In this study, to understand the mechanism of this heat treatment, the grain level microstructure of the additively manufactured Ti-6Al-4V was investigated using in situ high temperature EBSD up to 1000 °C, which allows the tracking of individual grains during a heat cycle. As a result, we found a random texture originating from the fine grains in the initial material and observed a significant suppression of α phase nucleation in the slow cooling after heating to 950 °C within the α and β dual phase regime but close to the the β-transus temperature at ~980 °C, which led to a coarse microstructure. Furthermore, the texture resulting from phase transformation of the additively manufactured Ti-6Al-4V assuming nucleation at the grain boundaries was modeled, using the double Burgers orientation relationship for the first time. The model successfully reproduced the measured texture, suggesting that the texture enhancement of the α phase by the additional heat treatment derives also from the variant selection during the phase transformation and nucleation on grain boundaries.
Metabolomics Meets Nutritional Epidemiology: Harnessing the Potential in Metabolomics Data
Authors: Brennan Lorraine , Hu Frank B. , Sun Qi
Published: October 2021

Traditionally, nutritional epidemiology is the study of the relationship between diet and health and disease in humans at the population level. Commonly, the exposure of interest is food intake. In recent years, nutritional epidemiology has moved from a “black box” approach to a systems approach where genomics, metabolomics and proteomics are providing novel insights into the interplay between diet and health. In this context, metabolomics is emerging as a key tool in nutritional epidemiology. The present review explores the use of metabolomics in nutritional epidemiology. In particular, it examines the role that food-intake biomarkers play in addressing the limitations of self-reported dietary intake data and the potential of using metabolite measurements in assessing the impact of diet on metabolic pathways and physiological processes. However, for full realisation of the potential of metabolomics in nutritional epidemiology, key challenges such as robust biomarker validation and novel methods for new metabolite identification need to be addressed. The synergy between traditional epidemiologic approaches and metabolomics will facilitate the translation of nutritional epidemiologic evidence to effective precision nutrition.
Metabolomics Differences of Glycine max QTLs Resistant to Soybean Looper
Authors: Yousefi-Taemeh Maryam , Lin Jie , Ifa Demian R. , Parrott Wayne , Kovinich Nik
Published: October 2021

Quantitative trait loci (QTLs) E and M are major soybean alleles that confer resistance to leaf-chewing insects, and are particularly effective in combination. Flavonoids and/or isoflavonoids are classes of plant secondary metabolites that previous studies agree are the causative agents of resistance of these QTLs. However, all previous studies have compared soybean genotypes that are of dissimilar genetic backgrounds, leaving it questionable what metabolites are a result of the QTL rather than the genetic background. Here, we conducted a non-targeted mass spectrometry approach without liquid chromatography to identify differences in metabolite levels among QTLs E, M, and both (EM) that were introgressed into the background of the susceptible variety Benning. Our results found that E and M mainly confer low-level, global differences in distinct sets of metabolites. The isoflavonoid daidzein was the only metabolite that demonstrated major increases, specifically in insect-treated M and EM. Interestingly, M confers increased daidzein levels in response to insect, whereas E restores M’s depleted daidzein levels in the absence of insect. Since daidzein levels do not parallel levels of resistance, our data suggest a novel mechanism that the QTLs confer resistance to insects by mediating changes in hundreds of metabolites, which would be difficult for the insect to evolve tolerance. Collective global metabolite differences conferred by E and M might explain the increased resistance of EM.
Effect of 17β-Estradiol, Progesterone, and Tamoxifen on Neurons Infected with Toxoplasma gondii In Vitro
Authors: Galván Ramírez María de la Luz , Dueñas-Jiménez Judith Marcela , Gutiérrez-Maldonado Adrián Fernando , Rodríguez Pérez Laura Rocío
Published: October 2021

Toxoplasma gondii (T. gondii) is the causal agent of toxoplasmosis, which produces damage in the central nervous system (CNS). Toxoplasma–CNS interaction is critical for the development of disease symptoms. T. gondii can form cysts in the CNS; however, neurons are more resistant to this infection than astrocytes. The probable mechanism for neuron resistance is a permanent state of neurons in the interface, avoiding the replication of intracellular parasites. Steroids regulate the formation of Toxoplasma cysts in mice brains. 17β-estradiol and progesterone also participate in the control of Toxoplasma infection in glial cells in vitro. The aim of this study was to evaluate the effects of 17β-estradiol, progesterone, and their specific agonists–antagonists on Toxoplasma infection in neurons in vitro. Neurons cultured were pretreated for 48 h with 17β-estradiol or progesterone at 10, 20, 40, 80, or 160 nM/mL or tamoxifen 1 μM/mL plus 17β-estradiol at 10, 20, 40, 80, and 160 nM/mL. In other conditions, the neurons were pretreated during 48 h with 4,4′,4″-(4-propyl-[1H] pyrozole-1,3,5-triyl) trisphenol or 23-bis(4-hydroxyphenyl) propionitrile at 1 nM/mL, and mifepristone 1 µM/mL plus progesterone at 10, 20, 40, 80, and 160 nM/mL. Neurons were infected with 5000 tachyzoites of the T. gondii strain RH. The effect of 17β estradiol, progesterone, their agonists, or antagonists on Toxoplasma infection in neurons was evaluated at 24 and 48 h by immunocytochemistry. T. gondii replication was measured with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction assay. 17β-Estradiol alone or plus tamoxifen reduced infected neurons (50%) compared to the control at 48 h. Progesterone plus estradiol decreased the number of intracellular parasites at 48 h of treatment compared to the control (p < 0.001). 4,4′,4″-(4-propyl-[1H] pyrozole-1,3,5-triyl) trisphenol and 23-bis(4-hydroxyphenyl) propionitrile reduced infected neurons at 48 h of treatment significantly compared to the control (p < 0.05 and p < 0.001, respectively). The Toxoplasma infection process was decreased by the effect of 17β-estradiol alone or combined with tamoxifen or progesterone in neurons in vitro. These results suggest the essential participation of progesterone and estradiol and their classical receptors in the regulation of T. gondii neuron infection.
What Do We Know about Candida auris? State of the Art, Knowledge Gaps, and Future Directions
Authors: Garcia-Bustos Victor , Cabanero-Navalon Marta D. , Ruiz-Saurí Amparo , Ruiz-Gaitán Alba C. , Salavert Miguel , Tormo María Á. , Pemán Javier
Published: October 2021

Candida auris has unprecedently emerged as a multidrug resistant fungal pathogen, considered a serious global threat due to its potential to cause nosocomial outbreaks and deep-seated infections with staggering transmissibility and mortality, that has put health authorities and institutions worldwide in check for more than a decade now. Due to its unique features not observed in other yeasts, it has been categorised as an urgent threat by the Centers for Disease Control and Prevention and other international agencies. Moreover, epidemiological alerts have been released in view of the increase of healthcare-associated C. auris outbreaks in the context of the COVID-19 pandemic. This review summarises the current evidence on C. auris since its first description, from virulence to treatment and outbreak control, and highlights the knowledge gaps and future directions for research efforts.
Microbe-Mediated Mn Oxidation—A Proposed Model of Mineral Formation
Authors: Sjöberg Susanne , Yu Changxun , Stairs Courtney , Allard Bert , Hallberg Rolf , Henriksson Sara , Åström Mats , Dupraz Christophe
Published: October 2021

Manganese oxides occur in a wide range of environmental settings either as coatings on rocks, sediment, and soil particles, or as discrete grains. Although the production of biologically mediated Mn oxides is well established, relatively little is known about microbial-specific strategies for utilizing Mn in the environment and how these affect the morphology, structure, and chemistry of associated mineralizations. Defining such strategies and characterizing the associated mineral properties would contribute to a better understanding of their impact on the local environment and possibly facilitate evaluation of biogenicity in recent and past Mn accumulations. Here, we supplement field data from a Mn rock wall deposit in the Ytterby mine, Sweden, with data retrieved from culturing Mn oxidizers isolated from this site. Microscopic and spectroscopic techniques are used to characterize field site products and Mn precipitates generated by four isolated bacteria (Hydrogenophaga sp., Pedobacter sp., Rhizobium sp., and Nevskia sp.) and one fungal-bacterial co-culture (Cladosporium sp.—Hydrogenophaga sp. Rhizobium sp.—Nevskia sp.). Two of the isolates (Pedobacter sp. and Nevskia sp.) are previously unknown Mn oxidizers. At the field site, the onset of Mn oxide mineralization typically occurs in areas associated with globular wad-like particles and microbial traces. The particles serve as building blocks in the majority of the microstructures, either forming the base for further growth into laminated dendrites-botryoids or added as components to an existing structure. The most common nanoscale structures are networks of Mn oxide sheets structurally related to birnessite. The sheets are typically constructed of very few layers and elongated along the octahedral chains. In places, the sheets bend and curl under to give a scroll-like appearance. Culturing experiments show that growth conditions (biofilm or planktonic) affect the ability to oxidize Mn and that taxonomic affiliation influences crystallite size, structure, and average oxidation state as well as the onset location of Mn precipitation.
Uptake of Be(II) by Cement in Degradation Stage I: Wet-Chemistry and Molecular Dynamics Studies
Authors: Çevirim-Papaioannou Neşe , Han Sangsoo , Androniuk Iuliia , Um Wooyong , Altmaier Marcus , Gaona Xavier
Published: October 2021

The uptake of beryllium by hardened cement paste (HCP, with CEM I 42,5 N BV/SR/LA type) in degradation stage I was investigated with a series of batch sorption experiments with 10−6 M ≤ [Be(II)]0 ≤ 10−2.5 M and 2 g·L−1 ≤ [S/L] ≤ 50 g·L−1. All experiments were performed under Ar atmosphere at T = (22 ± 2) °C. Solubility limits calculated for α-Be(OH)2(cr) in the conditions of the cement pore water were used to define the experimental window in the sorption experiments. Beryllium sorbs strongly on HCP under all of the investigated conditions, with log Rd ≈ 5.5 (Rd in L⋅kg−1). Sorption isotherms show a linear behavior with a slope of ≈+1 (log [Be(II)]solid vs. log [Be(II)]aq) over four orders of magnitude (10−8 M ≤ [Be(II)]aq ≤ 10−4 M), which confirm that the uptake is controlled by sorption processes and that solubility phenomena do not play any role within the considered boundary conditions. The similar uptake observed for beryllium in calcium silicate hydrate (C-S-H) phases supports that the C-S-H phases are the main sink of Be(II) in cement. The strong uptake observed for Be(II) agrees with the findings reported for heavier metal ions, e.g., Zn(II), Eu(III), Am(III), or Th(IV). The exceptional sorption properties of beryllium can be partially explained by its small size, which result in a charge-to-size ratio (z/d) of the same order as Eu(III) or Am(III). Kinetic experiments confirm the slow uptake of Be(II), which is characterized by a two-step process. In analogy to other strongly sorbing metal ions such as Zn(II) or Th(IV), a fast surface complexation (t < 4 days) followed by a slower incorporation of Be(II) in the C-S-H structure (t ≥ 60 days) are proposed. The surface complexation was studied in detail with molecular dynamic simulations, and the most common surface species are identified and described. This work provides the first experimental evidence supporting the strong uptake of Be(II) by HCP in degradation stage I, further extending previous findings on C-S-H phases and HCP in degradation stage II. These results overcome previous conservative estimates assuming no or only a weak uptake in cementitious systems and represent a relevant contribution for the quantitative assessment on the retention/mobilization of beryllium in the context of nuclear waste disposal.
Biomedical Applications of Chinese Herb-Synthesized Silver Nanoparticles by Phytonanotechnology
Authors: Islam Rehmat , Sun Leming , Zhang Lianbing
Published: October 2021

Recent advances in nanotechnology have opened up new avenues for the controlled synthesis of nanoparticles for biomedical and pharmaceutical applications. Chinese herbal medicine is a natural gift to humanity, and it has long been used as an antibacterial and anticancer agent. This study will highlight recent developments in the phytonanotechnological synthesis of Chinese herbal medicines to utilize their bioactive components in biomedical and therapeutic applications. Biologically synthesized silver nanoparticles (AgNPs) have emerged as a promising alternative to chemical and physical approaches for various biomedical applications. The comprehensive rationale of combinational or synergistic effects of Chinese herb-based AgNPs synthesis was investigated with superior physicochemical and biological properties, and their biomedical applications, including antimicrobial and anticancer activity and wound healing properties. AgNPs can damage the cell ultrastructure by triggering apoptosis, which includes the formation of reactive oxygen species (ROS), DNA disintegration, protein inactivation, and the regulation of various signaling pathways. However, the anticancer mechanism of Chinese herbal medicine-based AgNPs is more complicated due to the potential toxicity of AgNPs. Further in-depth studies are required to address Chinese herbs’ various bioactive components and AgNPs as a synergistic approach to combat antimicrobial resistance, therapeutic efficiency of drug delivery, and control and prevention of newly emerged diseases.
Mono- and Dicationic DABCO/Quinuclidine Composed Nanomaterials for the Loading of Steroidal Drug: 32 Factorial Design and Physicochemical Characterization
Authors: Fernandes Ana R. , Sanchez-Lopez Elena , Santini Antonello , Santos Tiago dos , Garcia Maria L. , Silva Amélia M. , Souto Eliana B.
Published: October 2021

Oil-in-water nanoemulsions (NEs) are considered a suitable nanotechnological approach to improve the eye-related bioavailability of lipophilic drugs. The potential of cationic NEs is prominent due to the electrostatic interaction that occurs between the positively charged droplets with the negatively charged mucins present in the tear film. This interaction offers prolonged NEs residence at the ocular surface, increasing the drug absorption. Triamcinolone acetonide (TA) is one of the first pharmacologic strategies applied as an intravitreal injection in the treatment of age-related macular degeneration (AMD). Newly synthesized quaternary derivatives of 1,4-diazabicyclo[2.2.2]octane (DABCO) and quinuclidine surfactants have been screened with the purpose to select the best compound to formulate long-term stable NEs that combine the best physicochemical properties for the loading of TA intended for ocular administration.
Broadband Achromatic Metasurfaces for Longwave Infrared Applications
Authors: Song Naitao , Xu Nianxi , Shan Dongzhi , Zhao Yuanhang , Gao Jinsong , Tang Yang , Sun Qiao , Chen Xin , Wang Yansong , Feng Xiaoguo
Published: October 2021

Longwave infrared (LWIR) optics are essential for several technologies, such as thermal imaging and wireless communication, but their development is hindered by their bulk and high fabrication costs. Metasurfaces have recently emerged as powerful platforms for LWIR integrated optics; however, conventional metasurfaces are highly chromatic, which adversely affects their performance in broadband applications. In this work, the chromatic dispersion properties of metasurfaces are analyzed via ray tracing, and a general method for correcting chromatic aberrations of metasurfaces is presented. By combining the dynamic and geometric phases, the desired group delay and phase profiles are imparted to the metasurfaces simultaneously, resulting in good achromatic performance. Two broadband achromatic metasurfaces based on all-germanium platforms are demonstrated in the LWIR: a broadband achromatic metalens with a numerical aperture of 0.32, an average intensity efficiency of 31%, and a Strehl ratio above 0.8 from 9.6 μm to 11.6 μm, and a broadband achromatic metasurface grating with a constant deflection angle of 30° from 9.6 μm to 11.6 μm. Compared with state-of-the-art chromatic-aberration-restricted LWIR metasurfaces, this work represents a substantial advance and brings the field a step closer to practical applications.
Mechanisms of Upconversion Luminescence of Er3+-Doped NaYF4 via 980 and 1530 nm Excitation
Authors: Liu Yu , Zhou Ziwen , Zhang Shaojian , Zhao Enming , Ren Jing , Liu Lu , Zhang Jianzhong
Published: October 2021

To date, the mechanisms of Er3+ upconversion luminescence via 980 and 1530 nm excitation have been extensively investigated; however, based on discussions, they either suffer from the lack of convincing evidence or require elaborated and time-consuming numerical simulations. In this work, the steady-state and time-resolved upconversion luminescence data of Er3+-doped NaYF4 were measured; we therefore investigated the upconversion mechanisms of Er3+ on the basis of the spectroscopic observations and the simplified rate equation modeling. This work provides a relatively simple strategy to reveal the UCL mechanisms of Er3+ upon excitation with various wavelengths, which may also be used in other lanthanide ion-doped systems.
Precision Food Parenting: A Proposed Conceptual Model and Research Agenda
Authors: Baranowski Tom , Thompson Debbe , Hughes Sheryl O. , O’Connor Teresia M.
Published: October 2021

Precision medicine, nutrition and behavioral interventions are attempting to move beyond the specification of therapies applied to groups, since some people benefit, some do not and some are harmed by the same therapy. Instead, precision therapies are attempting to employ diverse sets of data to individualize or tailor interventions to optimize the benefits for the receiving individuals. The benefits to be achieved are mostly in the distant future, but the research needs to start now. While precision pediatric nutrition will combine diverse demographic, behavioral and biological variables to specify the optimal foods a child should eat to optimize health, precision food parenting will combine diverse parent and child psychosocial and related variables to identify the optimal parenting practices to help a specific child accept and consume the precision nutrition specified foods. This paper presents a conceptual overview and hypothetical model of factors we believe are needed to operationalize precision food parenting and a proposed research agenda to better understand the many specified relationships, how they change over the age of the child, and how to operationalize them to encourage food parenting practices most likely to be effective at promoting healthy child food choices.
Coffeeberry Activates the CaMKII/CREB/BDNF Pathway, Normalizes Autophagy and Apoptosis Signaling in Nonalcoholic Fatty Liver Rodent Model
Authors: Lu Meng-Chun , Lee I-Te , Hong Ling-Zong , Ben-Arie Eyal , Lin Yu-Hsuan , Lin Wei-Ting , Kao Pei-Yu , Yang Mei-Due , Chan Yin-Ching
Published: October 2021

Nonalcoholic fatty liver disease (NAFLD) shows extensive liver cell destruction with lipid accumulation, which is frequently accompanied by metabolic comorbidities and increases mortality. This study aimed to investigate the effects of coffeeberry (CB) on regulating the redox status, the CaMKII/CREB/BDNF pathway, autophagy, and apoptosis signaling by a NAFLD rodent model senescence-accelerated mice prone 8 (SAMP8). Three-month-old male SAMP8 mice were divided into a control group and three CB groups (50, 100, and 200 mg/kg BW), and fed for 12 weeks. The results show that CB reduced hepatic malondialdehyde and carbonyl protein levels. CB significantly enhanced Ca2+/calmodulin-dependent protein kinase II (CaMKII) and brain-derived neurotrophic factor (BDNF) and reduced the phospho-cAMP response element-binding protein (p-CREB)/CREB ratio. In addition, CB increased the silent information regulator T1 level, promoted Beclin 1 and microtubule-associated protein light chain 3 II expressions, and reduced phosphorylated mammalian target of rapamycin and its downstream p-p70s6k levels. CB also inhibited the expressions of apoptosis-related factors poly (ADP-ribose) polymerase-1 and the apoptosis-inducing factor. In conclusion, CB might protect the liver by reducing oxidative stress, activating the CaMKII/CREB/BDNF pathway, and improving autophagic and apoptotic expressions in a dose-dependent manner.