bluuebunny/crossref_metadata_2025 huggingface dataset:
Fatigue-Induced Damage in High-Strength Concrete Microstructure
Authors: Oneschkow Nadja , Scheiden Tim , Hüpgen Markus , Rozanski Corinna , Haist Michael
Published: September 2021

A high-strength concrete subjected to compressive fatigue loading with two maximum stress levels was investigated and the behaviour was evaluated using the macroscopic damage indicators, strain and acoustic emission hits (AE-hits), combined with microstructural analyses utilising light microscopy and scanning electron microscopy (SEM). A clustering technique using Gaussian mixture modelling combined with a posterior probability of 0.80 was firstly applied to the AE-hits caused by compressive fatigue loading, leading to two clusters depending on the maximum stress level. Only a few cracks were visible in the microstructure using light microscopy and SEM, even in phase III of the strain development, which is shortly before failure. However, bluish impregnated areas in the mortar matrix of higher porosity or defects, changing due to the fatigue loading, were analysed. Indications were found that the fatigue damage process is continuously ongoing on a micro- or sub-microscale throughout the mortar matrix, which is difficult to observe on a mesoscale by imaging. Furthermore, the results indicate that two different damage mechanisms take place, which are pronounced depending on the maximum stress level. This might be due to diffuse and widespread compressive damage and localised tensile damage, as the findings documented in the literature suggest.
Hardness Prediction of Grind-Hardening Layer Based on Integrated Approach of Finite Element and Cellular Automata
Authors: Guo Yu , Liu Minghe , Yan Yutao
Published: September 2021

As an emerging composite processing technology, the grind-hardening process implements efficient removal on workpiece materials and surface strengthening by the effective utilization of grinding heat. The strengthening effect of grind-hardening on a workpiece surface is principally achieved by a hardened layer, which is chiefly composed of martensite. As a primary parameter to evaluate the strengthening effect, the hardness of the hardened layer mostly depends on the surface microstructure of the workpiece. On this basis, this paper integrated the finite element (FE) and cellular automata (CA) approach to explore the distribution and variation of the grinding temperature of the workpiece surface in a grind-hardening process. Moreover, the simulation of the transformation process of “initial microstructure–austenite–martensite” for the workpiece helps determine the martensite fraction and then predict the hardness of the hardened layer with different grinding parameters. Finally, the effectiveness of the hardness prediction is confirmed by the grind-hardening experiment. Both the theoretical analysis and experiment results show that the variation in the grinding temperature will cause the formation to a certain depth of a hardened layer on the workpiece surface in the grind-hardening process. Actually, the martensite fraction determines the hardness of the hardened layer. As the grinding depth and feeding speed increase, the martensite fraction grows, which results in an increase in its hardness value.
Silicon Nitride and Hydrogenated Silicon Nitride Thin Films: A Review of Fabrication Methods and Applications
Authors: Hegedüs Nikolett , Balázsi Katalin , Balázsi Csaba
Published: September 2021

Silicon nitride (SiNx) and hydrogenated silicon nitride (SiNx:H) thin films enjoy widespread scientific interest across multiple application fields. Exceptional combination of optical, mechanical, and thermal properties allows for their utilization in several industries, from solar and semiconductor to coated glass production. The wide bandgap (~5.2 eV) of thin films allows for its optoelectronic application, while the SiNx layers could act as passivation antireflective layers or as a host matrix for silicon nano-inclusions (Si-ni) for solar cell devices. In addition, high water-impermeability of SiNx makes it a potential candidate for barrier layers of organic light emission diodes (OLEDs). This work presents a review of the state-of-the-art process techniques and applications of SiNx and SiNx:H thin films. We focus on the trends and latest achievements of various deposition processes of recent years. Historically, different kinds of chemical vapor deposition (CVD), such as plasma enhanced (PE-CVD) or hot wire (HW-CVD), as well as electron cyclotron resonance (ECR), are the most common deposition methods, while physical vapor deposition (PVD), which is primarily sputtering, is also widely used. Besides these fabrication methods, atomic layer deposition (ALD) is an emerging technology due to the fact that it is able to control the deposition at the atomic level and provide extremely thin SiNx layers. The application of these three deposition methods is compared, while special attention is paid to the effect of the fabrication method on the properties of SiNx thin films, particularly the optical, mechanical, and thermal properties.
Evaluation of Various Surface Cleaning Techniques Inside Tunnels on Pavement Skid Resistance
Authors: Marcobal José Ramon , Salado Freddie , Flintsch Gerardo
Published: September 2021

A request started a comprehensive investigation on the Skid Resistance (SR) inside a highway tunnel in Madrid, Spain, to determine methods that will improve or maintain the SR above the minimum required level (60), after the application of Hydroblasting, without the need of pavement surface rehabilitation. The right lane located on eight sections inside tunnel XC was used as a test section, in which three went thru the application of water pressure applied weekly, biweekly, and monthly. Three other sections for surface sweeping at the same frequencies and two untreated sections as control. Using the Microgriptester, weekly SR measurements taken before and after tracked the pavement response. Results showed that SR decreased weekly depending on the frequency of the treatment applied and for higher frequencies, SR was almost at the same level. Water pressure and sweeping applied weekly, biweekly, and monthly, during the two months testing period, maintained the SR level above the required value of 60 and the untreated sections showed that pavement surface must be treated to maintain the SR above 60.
Comparison of CAD and Voxel-Based Modelling Methodologies for the Mechanical Simulation of Extrusion-Based 3D Printed Scaffolds
Authors: Vega Gisela , Paz Rubén , Gleadall Andrew , Monzón Mario , Alemán-Domínguez María Elena
Published: September 2021

Porous structures are of great importance in tissue engineering. Most scaffolds are 3D printed, but there is no single methodology to model these printed parts and to apply finite element analysis to estimate their mechanical behaviour. In this work, voxel-based and geometry-based modelling methodologies are defined and compared in terms of computational efficiency, dimensional accuracy, and mechanical behaviour prediction of printed parts. After comparing the volumes and dimensions of the models with the theoretical and experimental ones, they are more similar to the theoretical values because they do not take into account dimensional variations due to the printing temperature. This also affects the prediction of the mechanical behaviour, which is not accurate compared to reality, but it makes it possible to determine which geometry is stiffer. In terms of comparison of modelling methodologies, based on process efficiency, geometry-based modelling performs better for simple or larger parts, while voxel-based modelling is more advantageous for small and complex geometries.
Bayesian Optimization Design of Inlet Volute for Supercritical Carbon Dioxide Radial-Flow Turbine
Authors: Bian Chao , Zhang Shaojie , Yang Jinguang , Liu Haitao , Zhao Feng , Wang Xiaofang
Published: September 2021

The radial-flow turbine, a key component of the supercritical CO2 (S-CO2) Brayton cycle, has a significant impact on the cycle efficiency. The inlet volute is an important flow component that introduces working fluid into the centripetal turbine. In-depth research on it will help improve the performance of the turbine and the entire cycle. This article aims to improve the volute flow capacity by optimizing the cross-sectional geometry of the volute, thereby improving the volute performance, both at design and non-design points. The Gaussian process surrogate model based parameter sensitivity analysis is first conducted, and then the optimization process is implemented by Bayesian optimization (BO) wherein the acquisition function is used to query optimal design. The results show that the optimized volute has better and more uniform flow characteristics at design and non-design points. It has a smoother off-design conditions performance curve. The total pressure loss coefficient at the design point of the optimized volute is reduced by 33.26%, and the flow deformation is reduced by 54.55%.
Dynamic Modeling and Vibration Characteristics Analysis of Deep-Groove Ball Bearing, Considering Sliding Effect
Authors: Li Fanjie , Li Xiaopeng , Shang Dongyang
Published: September 2021

To study the vibration characteristics of deep-groove ball bearing, considering the influence of sliding, the dynamic model of the DGB 6205 system is established in this paper. The DGB 6205 system model includes the movement of the bearing inner ring in the X and Y directions, the rotation of the cage, the rotation movement of each ball, the revolution movement of each ball and the movement along the radial direction of each ball. Based on the system model, the differential equations of motion of the system are established, and the correctness of the model is verified by experiment. The slip characteristics of the DGB 6205 system are studied by numerical simulation. At the same time, the influence of time-varying load on the vibration characteristics of the system is studied. Then, the sensitivity of system parameters is analyzed. The results show that the sliding speed between the ball and the inner raceway is greater than that between the ball and the outer raceway. The radial vibration response of DGB 6205 system under time-varying load is less than that under constant load. The increase of radial clearance will increase the vibration response of DGB 6205 system.
The Influence of NeoTrie VR’s Immersive Virtual Reality on the Teaching and Learning of Geometry
Authors: Rodríguez José L. , Romero Isabel , Codina Antonio
Published: September 2021

The use of dynamic, three-dimensional software with virtual reality offers new possibilities for the teaching and learning of geometry. We explore the effects of introducing the immersive virtual reality software NeoTrie VR in real classes. Within a Design Research framework, we present qualitative observational data to report how the collaboration among a software development company, university researchers, and schools produces improvements in the design and updating of the software; the geometrical content, representations, and mathematical activity that students have access to as well as the way teachers conceive and manage the teaching of geometry.
Attention-TCN-BiGRU: An Air Target Combat Intention Recognition Model
Authors: Teng Fei , Song Yafei , Guo Xinpeng
Published: September 2021

The prerequisite for victory in war is the rapid and accurate identification of the tactical intention of the target on the battlefield. The efficiency of manual recognition of the combat intention of air targets is becoming less and less effective with the advent of information warfare. Moreover, if the traditional method of combat intention of air targets is based only on data from a single moment in time, the characteristic information on the time-series data is difficult to capture effectively. In this context, we design a new deep learning method attention mechanism with temporal convolutional network and bidirectional gated recurrent unit (Attention-TCN-BiGRU) to improve the recognition of the combat intent of air targets. Specifically, suitable characteristics are selected based on the combat mission and air posture to construct a characteristic set of air target intentions and encode them into temporal characteristics. Each characteristic in the characteristic set is given an appropriate weight through the attention mechanism. In addition, temporal convolutional network (TCN) is used to mine the data for latent characteristics and bidirectional gated recurrent unit (BiGRU) is used to capture long-term dependencies in the data. Experiments comparing with other methods and ablation demonstrate that Attention-TCN-BiGRU outperforms state-of-the-art methods in terms of accuracy in recognizing target intent in the air.
Credit Risk Theoretical Model on the Base of DCC-GARCH in Time-Varying Parameters Framework
Authors: Moiseev Nikita , Sorokin Aleksander , Zvezdina Natalya , Mikhaylov Alexey , Khomyakova Lyubov , Danish Mir Sayed Shah
Published: September 2021

The research paper is devoted to developing a mathematical approach for dealing with time-varying parameters in rolling window logit models for credit risk assessment. Forecasting coefficients yields a better model accuracy than a trivial approach of using computed past statistics parameters for the next time period. In this paper, a new method of dealing with time-varying parameters of scoring models is proposed, which is aimed at computing the default probability of a borrower. It was empirically shown that in a continuously changing economic environment factors’ influence on a target variable is also changing. Therefore, forecasting coefficients yields a better financial result than simply applying parameters obtained by accumulated statistics over past time periods. The paper develops a new theoretical approach, incorporating a combination of the ARIMA class model, the DCC-GARCH model and the state–space model, which is more accurate, than using only the ARIMA model. Rigorous simulation testing is provided to confirm the efficiency of the proposed method.
Three-Point Bending Fatigue Behavior of Aluminum Foam Sandwich Panels with Different Density Core Material
Authors: Yao Cheng , Hu Zhengfei , Mo Fan
Published: September 2021

The monotonic and fatigue strength of adhesively bonded aluminum foam sandwich panels with different densities of core aluminum foam (0.3 g/cm3, 0.4 g/cm3, 0.6 g/cm3) were investigated in three-point bending tests to study the flexural fatigue behavior of aluminum foam sandwich panels. The force cycle curves, deflection curves, and hysteretic curves are presented to describe the fatigue process of aluminum foam sandwich panels. Their fatigue fracture modes are completely different, the failure modes of the low-density cores (0.3 g/cm3, 0.4 g/cm3) are debonding and face fatigue, whereas the failure mode of the high-density core (0.6 g/cm3) is face fatigue without debonding. The reason is that high-density aluminum foam cores with lower porosity have a larger joining face, which can also provide higher strength and lead to a longer fatigue life.
Anticorrosion Behaviour of SS304 Microgroove Surfaces in Saline Water
Authors: Annakodi Vivek Anand , Arvind Singh Ramachandra , Jayalakshmi Subramanian , Zhang Yupeng , Srinivas Rao Koppula , Shabadi Rajashekhara
Published: September 2021

The 304 Stainless Steel (SS304) is severely affected by salt water corrosion due to its high surface wettability. By reducing its surface wettability, its corrosion can be reduced. To achieve this, topographical modification of the steel surface is an effective route. In this work, SS304 flat surfaces were topographically modified into microgrooves (ridge width 250 μm to 500 μm, groove width 200 μm, width ratio = ridge width/groove width >1). Wire cut electrical discharge machining was used to fabricate the microgrooves. Long-term wetting characteristics and long-term corrosion behaviour of flat surface and microgrooves were studied. The influence of the nature of wetting of the tested surfaces on their corrosion behaviour was examined. The sessile drop method and potentiodynamic polarization tests in sodium chloride (3.5 wt. % NaCl) solution (intermittent and continuous exposures for 168 h) were studied to characterize their wetting and corrosion behaviours, respectively. Topographical modification imparted long-term hydrophobicity and, as a consequence, long-term anticorrosion ability of the steel surface. Micropatterning reduced the corrosion rate by two orders of magnitude due to reduction in interfacial contact area with the corrosive fluid via composite wetting, i.e., solid–liquid–air interface. Microgrooves showed corrosion inhibition efficiency ≥88%, upon long-term exposure to NaCl solution. By comparing the wetting and corrosion behaviours of the microgrooves with those of the previously studied microgrooves (ridge width/groove width <1), it was found that the surface roughness of their ridges strongly influences their wetting and corrosion properties.
Effect of Carbon Content and Intercritical Annealing on Microstructure and Mechanical Tensile Properties in FeCMnSiCr TRIP-Assisted Steels
Authors: Tesser Enzo , Silva Carlos , Artigas Alfredo , Monsalve Alberto
Published: September 2021

Four TRIP (Transformation Induced Plasticity) assisted steels, three TBF (TRIP Bainitic Ferrite) steels and one TPF (TRIP Polygonal Ferrite) steel, were manufactured from three different carbon contents (0.2, 0.3 and 0.4 wt.% C), to study the evolution of their microstructure and tensile mechanical properties in 15 mm thick plates. TBF steels were subjected to the same austenitization heat treatment and subsequent bainitization isothermal treatment. The TPF steel was subjected to an intercritical annealing and subsequent isothermal bainitization treatment. All were microstructurally characterized by optical, scanning electron and atomic force microscopy, as well as X-ray diffraction. Mechanically, they were characterized by the ASTM E8 tensile test and fractographies. For the TBF steels, the results showed that when the carbon content increased, there were an increase in volume fraction of retained austenite, of the microconstituent “martensite/retained austenite” and in the tensile strength; and a decrease in the volume fraction of bainitic ferrite matrix and elongation; with an improvement in TRIP behavior due to the increase in retained austenite. The TPF steel presented around 50% ductile polygonal ferrite developing better TRIP behavior than the TBF steels. The evolution of the fractographies was ductile to brittle for TBF steels with an increase in carbon content, and for TPF, the appearance of the fracture surface was ductile.
Examining the Effects of Netropsin on the Curvature of DNA A-Tracts Using Electrophoresis
Authors: Miller Jillian , Peters Justin
Published: September 2021

A-tracts are sequences of repeated adenine bases that, under the proper conditions, are capable of mediating DNA curvature. A-tracts occur naturally in the regulatory regions of many organisms, yet their biological functions are not fully understood. Orienting multiple A-tracts together constructively or destructively in a phase has the potential to create different shapes in the DNA helix axis. One means of detecting these molecular shape differences is from altered DNA mobilities measured using electrophoresis. The small molecule netropsin binds the minor groove of DNA, particularly at AT-rich sequences including A-tracts. Here, we systematically test the hypothesis that netropsin binding eliminates the curvature of A-tracts by measuring the electrophoretic mobilities of seven 98-base pair DNA samples containing different numbers and arrangements of centrally located A-tracts under varying conditions with netropsin. We find that netropsin binding eliminates the mobility difference between the DNA fragments with different A-tract arrangements in a concentration-dependent manner. This work provides evidence for the straightening of A-tracts upon netropsin binding and illustrates an artificial approach to re-sculpt DNA shape.
Novel Antimicrobial Peptides from a Cecropin-Like Region of Heteroscorpine-1 from Heterometrus laoticus Venom with Membrane Disruption Activity
Authors: Erviana Rima , Saengkun Yutthakan , Rungsa Prapenpuksiri , Jangpromma Nisachon , Tippayawat Patcharaporn , Klaynongsruang Sompong , Daduang Jureerut , Daduang Sakda
Published: September 2021

The increasing antimicrobial-resistant prevalence has become a severe health problem. It has led to the invention of a new antimicrobial agent such as antimicrobial peptides. Heteroscorpine-1 is an antimicrobial peptide that has the ability to kill many bacterial strains. It consists of 76 amino acid residues with a cecropin-like region in N-terminal and a defensin-like region in the C-terminal. The cecropin-like region from heteroscorpine-1 (CeHS-1) is similar to cecropin B, but it lost its glycine-proline hinge region. The bioinformatics prediction was used to help the designing of mutant peptides. The addition of glycine-proline hinge and positively charged amino acids, the deletion of negatively charged amino acids, and the optimization of the hydrophobicity of the peptide resulted in two mutant peptides, namely, CeHS-1 GP and CeHS-1 GPK. The new mutant peptide showed higher antimicrobial activity than the native peptide without increasing toxicity. The interaction of the peptides with the membrane showed that the peptides were capable of disrupting both the inner and outer bacterial cell membrane. Furthermore, the SEM analysis showed that the peptides created the pore in the bacterial cell membrane resulted in cell membrane disruption. In conclusion, the mutants of CeHS-1 had the potential to develop as novel antimicrobial peptides.
Complex Activity and Sensor Potential toward Metal Ions in Environmental Water Samples of N-Phthalimide Azo-Azomethine Dyes
Authors: Georgieva Stela , Bezfamilnyi Artem , Georgiev Anton , Varbanov Marian
Published: September 2021

Herein, the spectral and electrochemical characterizations of three different substituted N-phthalimide azo-azomethine (NAA) dyes (L) containing an o-hydroxy group and their NAA-M(II) chelates [M(II): Cu, Ni, Co, Pb] were reported by using UV–Vis and fluorescence spectroscopy and potentiometric and voltamperometric techniques. The pK value of the dyes as well as the stoichiometry and stability of the NAA-metal chelates were studied, and the stoichiometry was found to be mostly 1:2 (ML2) with high complex stability constant values. The sensor activity of N-phthalimide azo-azomethine derivatives toward pH and metal ions has been also investigated and tested for indicator application in acid–base analysis and detection of Cu(II) ions in real samples of surface river water using voltamperometric detection. The results showed that one of the ligands possesses the highest electrochemical response upon binding to copper ions and could be successfully used in the analysis of copper in water at a concentration range of the analyte from 3.7 × 10−7 to 5.0 × 10−6 mol L−1, with analytical characteristics of the method being Sr = 1.5%, LOD = 3.58 µg L−1 and LOQ =11.9 µg L−1
Effects of Wine Components in Inflammatory Bowel Diseases
Authors: Vrdoljak Josip , Kumric Marko , Ticinovic Kurir Tina , Males Ivan , Martinovic Dinko , Vilovic Marino , Bozic Josko
Published: September 2021

With the rising prevalence of Inflammatory bowel disease (IBD) worldwide, and the rising cost of treatment with novel biological drugs, there is an increasing interest in various diets and natural foods as a potential way to control/modulate IBD. As recent data indicates that diet can modify the metabolic responses essential for the resolution of inflammation, and as wine compounds have been shown to provide substantial anti-inflammatory effect, in this review we aimed to discuss the current evidence concerning the impact of biological compounds present in wine on IBD. A number of preclinical studies brought forth strong evidence on the mechanisms by which molecules in wine, such as resveratrol or piceatannol, provide their anti-inflammatory, anti-oxidative, anti-tumor, and microbiota-modulation effects. However, concerning the effects of alcohol, it is still unclear how the amount of ethanol ingested within the framework of moderate wine consumption (1–2 glasses a day) affects patients with IBD, as human studies regarding the effects of wine on patients with IBD are scarce. Nevertheless, available evidence justifies the conductance of large-scale RCT trials on human subjects that will finally elucidate whether wine can offer real benefits to the IBD population.
Effects of Acute Heat and Cold Exposures at Rest or during Exercise on Subsequent Energy Intake: A Systematic Review and Meta-Analysis
Authors: Millet Juliette , Siracusa Julien , Tardo-Dino Pierre-Emmanuel , Thivel David , Koulmann Nathalie , Malgoyre Alexandra , Charlot Keyne
Published: September 2021

The objective of this meta-analysis was to assess the effect of acute heat/cold exposure on subsequent energy intake (EI) in adults. We searched the following sources for publications on this topic: PubMed, Ovid Medline, Science Direct and SPORTDiscus. The eligibility criteria for study selection were: randomized controlled trials performed in adults (169 men and 30 women; 20–52 years old) comparing EI at one or more meals taken ad libitum, during and/or after exposure to heat/cold and thermoneutral conditions. One of several exercise sessions could be realized before or during thermal exposures. Two of the thirteen studies included examined the effect of heat (one during exercise and one during exercise and at rest), eight investigated the effect of cold (six during exercise and two at rest), and three the effect of both heat and cold (two during exercise and one at rest). The meta-analysis revealed a small increase in EI in cold conditions (g = 0.44; p = 0.019) and a small decrease in hot conditions (g = −0.39, p = 0.022) for exposure during both rest and exercise. Exposures to heat and cold altered EI in opposite ways, with heat decreasing EI and cold increasing it. The effect of exercise remains unclear.
Prevalence and Risk Factors of Food Insecurity among Mexican University Students’ Households
Authors: Nava-Amante Pablo Alejandro , Betancourt-Núñez Alejandra , Vizmanos Barbara , Salas-García Miguel Amaury , Bernal-Orozco María Fernanda , Vargas-García Elisa J. , Díaz-López Andrés
Published: September 2021

Household food insecurity (FI) remains a major public health challenge worldwide. Data about perceived FI and its risk factors in Mexican university students are lacking. We aimed to assess FI’s prevalence and factors affecting it among university students’ households in Mexico. This cross-sectional analysis involved 7671 university students’ households using the 2018 Mexican National of Household Income and Expenditure Survey data. Variables analyzed included sociodemographic characteristics, and the 12-item validated Mexican Scale for Food Security (EMSA). Multivariable logistic regression modelling was performed to identify FI risk factors. The overall household FI prevalence was 30.8%. According to FI severity, prevalence rates were 16.3% for mild-FI, 8.8% for moderate-FI, and 5.7% for severe-FI. Low socioeconomic status (OR = 2.72; 95%CI: 2.09–3.54), low education level of household’s head (OR = 2.36; 95%CI: 1.90–2.94), self-ascription to an indigenous group (OR = 1.59; 95%CI: 1.41–1.79), attending public university (OR = 1.27; 95%CI: 1.13–1.43), female-headed household (OR = 1.26; 95%CI: 1.13–1.40), having worked recently (OR = 1.19; 95%CI: 1.07–1.33), and being in second year of studies (OR = 1.17; 95%CI: 1.03–1.33), were significantly related to FI. Our results confirm that FI is highly prevalent among Mexican university students’ households and that sociodemographic factors are essential in addressing this concern. Findings highlight the need for preventive programs and policies to alleviate FI.
6-Shogaol Mitigates Sepsis-Associated Hepatic Injury through Transcriptional Regulation
Authors: Guo Xiaoxuan , Qiu Jing , Qian Yongzhong
Published: September 2021

Sepsis-associated liver dysfunction presents a significant public health problem. 6-Shogaol is the key bioactive component in dry ginger, which has antioxidant and anti-inflammation capacity. The present study aims to investigate the preventive effect of 6-shogaol on sepsis-induced liver injury. 6-Shogaol was administered to mice for 7 consecutive days before being intraperitoneally injected with lipopolysaccharide (LPS). After 24 h, mice were sacrificed, and biochemical and transcriptomic analyses were performed. Our results demonstrated that 6-shogaol prevented LPS-induced impairment in antioxidant enzymes and elevation in malondialdehyde level in the liver. The hepatic inflammatory response was significantly suppressed by 6-shogaol through suppressing the MAPK/NFκB pathway. RNA-sequencing data analysis revealed that 41 overlapped genes between the LPS vs. control group and 6-shogaol vs. LPS group were identified, among which 36 genes were upregulated, and 5 genes were downregulated for the LPS vs. control group. These overlapped genes are enriched in inflammation-related pathways, e.g., TNF and NFκB. The mRNA expression of the overlapped genes was also verified in the LPS-induced BRL-3A cell model. In summary, 6-shogaol shows great potential as a natural chemopreventive agent to treat sepsis-associated hepatic disorders.
From Mum to Bum: An Observational Study Protocol to Follow Digestion of Human Milk Oligosaccharides and Glycoproteins from Mother to Preterm Infant
Authors: Henderickx Jannie G. E. , d’Haens Esther J. , Hemels Marieke A. C. , Schoorlemmer Mariëtte E. , Giezen Astrid , van Lingen Richard A. , Knol Jan , Belzer Clara
Published: September 2021

The nutritional requirements of preterm infants are challenging to meet in neonatal care, yet crucial for their growth, development and health. Aberrant maturation of the gastrointestinal tract and the microbiota could affect the digestion of human milk and its nutritional value considerably. Therefore, the main objective of the proposed research is to investigate how the intestinal microbiota of preterm and full-term infants differ in their ability to extract energy and nutrients from oligosaccharides and glycoproteins in human milk. This pilot study will be an observational, single-center study performed at the Neonatal Intensive Care Unit at Isala Women and Children’s Hospital (Zwolle, The Netherlands). A cohort of thirty mother–infant pairs (preterm ≤30 weeks of gestation, n = 15; full-term 37–42 weeks of gestation, n = 15) will be followed during the first six postnatal weeks with follow-up at three- and six-months postnatal age. We will collect human milk of all mothers, gastric aspirates of preterm infants and fecal samples of all infants. A combination of 16S rRNA amplicon sequencing, proteomics, peptidomics, carbohydrate analysis and calorimetric measurements will be performed. The role of the microbiota in infant growth and development is often overlooked yet offers opportunities to advance neonatal care. The ‘From Mum to Bum’ study is the first study in which the effect of a preterm gut microbiota composition on its metabolic capacity and subsequent infant growth and development is investigated. By collecting human milk of all mothers, gastric aspirates of preterm infants and fecal samples of all infants at each timepoint, we can follow digestion of human milk from the breast of the mother throughout the gastrointestinal tract of the infant, or ‘From Mum to Bum’.
Dietary Diversity and Undernutrition in Children Aged 6–23 Months in Sub-Saharan Africa
Authors: Aboagye Richard Gyan , Seidu Abdul-Aziz , Ahinkorah Bright Opoku , Arthur-Holmes Francis , Cadri Abdul , Dadzie Louis Kobina , Hagan John Elvis , Eyawo Oghenowede , Yaya Sanni
Published: September 2021

Dietary diversity plays a major role in the health status of children. However, evidence on its crucial role on children’s health status remains inconclusive in sub-Saharan Africa (SSA). In this study, we examined the association between dietary diversity and undernutrition among children aged 6–23 months in SSA. We pooled data from the most recent Demographic and Health Surveys of 32 countries in SSA from 2010 to 2020. A sample of 48,968 mother-child pairs of children within the ages of 6–23 months and mothers aged 15–49 years were included in this study. Multilevel logistic regression analysis was carried out to examine the association between dietary diversity and stunting, wasting, and underweight. The results were presented as crude odds ratios (cOR) and adjusted odds ratios (aOR) with their 95% confidence intervals. Statistical significance was set at p < 0.05. The overall prevalence of minimum dietary diversity was 25.1%, with South Africa recording the highest prevalence (43.9%) and Burkina Faso recording the lowest prevalence (5.6%). The highest prevalence of stunting was recorded by Burundi (51.8%) while the lowest prevalence was found in Ghana (13.6%), with an overall regional prevalence of 28.6%. For wasting, prevalence from all countries was found to be 9.4%. South Africa recorded the lowest prevalence of wasting (2.1%) while Niger recorded the highest prevalence (27.3%). Lastly, the prevalence of underweight ranged from 5.3% in South Africa to 41.8% in Niger, with an all-country prevalence of 16.4%. Children who had adequate minimum dietary diversity had 12% less likelihood of being stunted (aOR = 0.88, 95% CI = 0.83, 0.94), compared to those who had inadequate minimum dietary diversity. Having an adequate minimum dietary diversity significantly lowered the risk of underweight among children by 17% (aOR = 0.83, 95% CI = 0.77, 0.91). Having an adequate minimum dietary diversity was associated with 13% reduced odds of wasting among children (aOR = 0.87, 95% CI = 0.78, 0.97), compared to those who had inadequate minimum dietary diversity. This study highlights the significant association between minimum dietary diversity and stunting, wasting, and underweight among 6–23 month-old children in SSA. There is an urgent need for additional nutrition-specific interventions and strengthening of existing interventions aimed at improving infant and young child feeding practices, including complementary feeding practices among children aged 6–23 months in the 32 countries in SSA. Such interventions should focus more on countries where the prevalence of adequate minimum dietary diversity was low and undernutrition was high.
L-Carnitine Tartrate Supplementation for 5 Weeks Improves Exercise Recovery in Men and Women: A Randomized, Double-Blind, Placebo-Controlled Trial
Authors: Stefan Matthew , Sharp Matthew , Gheith Raad , Lowery Ryan , Ottinger Charlie , Wilson Jacob , Durkee Shane , Bellamine Aouatef
Published: September 2021

L-carnitine tartrate has been shown to improve relatively short-term recovery among athletes. However, there is a lack of research on the longer-term effects in the general population. Objective: The primary objectives of this randomized double-blind, placebo-controlled trial were to evaluate the effects of daily L-carnitine tartrate supplementation for 5 weeks on recovery and fatigue. Method: In this study, eighty participants, 21- to 65-years-old, were recruited. Participants were split into two groups of forty participants each, a placebo, and a L-carnitine Tartrate group. Seventy-three participants completed a maintenance exercise training program that culminated in a high-volume exercise challenge. Results: Compared to placebo, L-carnitine tartrate supplementation was able to improve perceived recovery and soreness (p = 0.021), and lower serum creatine kinase (p = 0.016). In addition, L-carnitine tartrate supplementation was able to blunt declines in strength and power compared to placebo following an exercise challenge. Two sub-analyses indicated that these results were independent of gender and age. Interestingly, serum superoxide dismutase levels increased significantly among those supplementing with L-carnitine tartrate. Conclusions: These findings agree with previous observations among healthy adult subjects and demonstrate that L-carnitine tartrate supplementation beyond 35 days is beneficial for improving recovery and reducing fatigue following exercise across gender and age.
An Overview of Achilles Tendinopathy Management
Authors: Santacaterina Fabio , Miccinilli Sandra , Bressi Federica , Sterzi Silvia , Bravi Marco
Published: September 2021

Background: Persistent tendon pain and swelling related to mechanical loading are the main signs of Achilles tendinopathy (AT). This condition is one of the most common tendinopathies of the lower limb affecting mainly athletes involved in running and jumping sports. Methods: we included pivotal papers retrieved from the literature (Pubmed, Google Scholar, PEDro, and Scopus) to present an overview of the management of AT, with a specific focus on conservative management. Results: An accurate and timely diagnosis of AT is necessary to set up early treatments and to manage the problem conservatively. Diagnosis is primarily based on clinical assessment; instrumental imaging may be helpful in confirming the clinical diagnosis. Conservative treatment is effective in most cases, mainly using physical exercise based on eccentric training. Other non-surgical treatments such as extracorporeal shock wave therapy, thermotherapies, and injections can be added to exercise. Surgical treatment is indicated for patients where the conservative treatments of at least six months fails. Conclusions: Conflicting results from numerous studies hamper to identify gold standard treatments asking for further well-conducted level I and II research about the management of AT.
A Broad-Based Mosquito Yeast Interfering RNA Pesticide Targeting Rbfox1 Represses Notch Signaling and Kills Both Larvae and Adult Mosquitoes
Authors: Mysore Keshava , Sun Longhua , Hapairai Limb K. , Wang Chien-Wei , Roethele Joseph B. , Igiede Jessica , Scheel Max P. , Scheel Nicholas D. , Li Ping , Wei Na , Severson David W. , Duman-Scheel Molly
Published: September 2021

Prevention of mosquito-borne infectious diseases will require new classes of environmentally safe insecticides and novel mosquito control technologies. Saccharomyces cerevisiae was engineered to express short hairpin RNA (shRNA) corresponding to mosquito Rbfox1 genes. The yeast induced target gene silencing, resulting in larval death that was observed in both laboratory and outdoor semi-field trials conducted on Aedes aegypti. High levels of mortality were also observed during simulated field trials in which adult females consumed yeast delivered through a sugar bait. Mortality correlated with defects in the mosquito brain, in which a role for Rbfox1 as a positive regulator of Notch signaling was identified. The larvicidal and adulticidal activities of the yeast were subsequently confirmed in trials conducted on Aedes albopictus, Anopheles gambiae, and Culex quinquefasciatus, yet the yeast had no impact on survival of select non-target arthropods. These studies indicate that yeast RNAi pesticides targeting Rbfox1 could be further developed as broad-based mosquito larvicides and adulticides for deployment in integrated biorational mosquito control programs. These findings also suggest that the species-specificity of attractive targeted sugar baits, a new paradigm for vector control, could potentially be enhanced through RNAi technology, and specifically through the use of yeast-based interfering RNA pesticides.
Gardenia jasminoides Attenuates Allergic Rhinitis-Induced Inflammation by Inhibiting Periostin Production
Authors: Pyun Bo-Jeong , Lee Joo Young , Kim Yu Jin , Ji Kon-Young , Jung Dong Ho , Park Ki-Sun , Jo Kyuhyung , Choi Susanna , Jung Myung-A , Kim Yun Hee , Kim Taesoo
Published: September 2021

Allergic rhinitis (AR) is a chronic inflammatory condition affecting the nasal mucosa of the upper airways. Herein, we investigated the effects of extracts from Gardenia jasminoides (GJ), a traditional herbal medicine with anti-inflammatory properties, on AR-associated inflammatory responses that cause epithelial damage. We investigated the inhibitory effects of water- and ethanol-extracted GJ (GJW and GJE, respectively) in an ovalbumin-induced AR mouse model and in splenocytes, differentiated Th2 cells, and primary human nasal epithelial cells (HNEpCs). Administering GJW and GJE to ovalbumin-induced AR mice improved clinical symptoms including behavior (sneezing and rubbing), serum cytokine levels, immune cell counts, and histopathological marker levels. Treatment with GJW and GJE reduced the secretion of Th2 cytokines in Th2 cells isolated and differentiated from the splenocytes of these mice. To investigate the underlying molecular mechanisms of AR, we treated IL-4/IL-13-stimulated HNEpCs with GJW and GJE; we found that these extracts significantly reduced the production of mitochondrial reactive oxygen species via the uncoupling protein-2 and periostin, a biomarker of the Th2 inflammatory response. Our results suggest that GJ extracts may potentially serve as therapeutic agents to improve the symptoms of AR by regulating the Th2 inflammatory response of the nasal epithelium.
Prerequisite Binding Modes Determine the Dynamics of Action of Covalent Agonists of Ion Channel TRPA1
Authors: Zsidó Balázs Zoltán , Börzsei Rita , Pintér Erika , Hetényi Csaba
Published: September 2021

Transient receptor potential ankyrin 1 (TRPA1) is a transmembrane protein channeling the influx of calcium ions. As a polymodal nocisensor, TRPA1 can be activated by thermal, mechanical stimuli and a wide range of chemically damaging molecules including small volatile environmental toxicants and endogenous algogenic lipids. After activation by such compounds, the ion channel opens up, its central pore widens allowing calcium influx into the cytosol inducing signal transduction pathways. Afterwards, the calcium influx desensitizes irritant evoked responses and results in an inactive state of the ion channel. Recent experimental determination of structures of apo and holo forms of TRPA1 opened the way towards the design of new agonists, which can activate the ion channel. The present study is aimed at the elucidation of binding dynamics of agonists using experimental structures of TRPA1-agonist complexes at the atomic level applying molecular docking and dynamics methods accounting for covalent and non-covalent interactions. Following a test of docking methods focused on the final, holo structures, prerequisite binding modes were detected involving the apo forms. It was shown how reversible interactions with prerequisite binding sites contribute to structural changes of TRPA1 leading to covalent bonding of agonists. The proposed dynamics of action allowed a mechanism-based forecast of new, druggable binding sites of potent agonists.
Evaluation of Aerosol Drug Delivery Options during Adult Mechanical Ventilation in the COVID-19 Era
Authors: Naughton Piers J. , Joyce Mary , Mac Giolla Eain Marc , O’Sullivan Andrew , MacLoughlin Ronan
Published: September 2021

Drug delivery devices used for aerosol therapy during mechanical ventilation to ease the symptoms of respiratory diseases provide beneficial treatment but can also pose challenges. Reflecting the significant changes in global guidance around aerosol usage and lung-protective ventilation strategies, seen in response to the COVID-19 pandemic, for the first time, we describe the drug delivery performance of commonly used devices under these conditions. Here, vibrating mesh nebuliser (VMN), jet nebuliser (JN) and pressurised metered-dose inhaler (pMDI) performance was assessed during simulated adult mechanical ventilation. Both standard test breathing patterns and those representatives of low tidal volume (LTV) ventilation with concurrent active and passive humidification were investigated. Drug delivery using a VMN was significantly greater than that with a JN and pMDI for both standard and LTV ventilation. Humidification type did not affect the delivered dose across all device types for standard ventilation. Significant variability in the pMDI dosing was evident, depending on the timing of actuation and the adapter type used. pMDI actuation synchronised with inspiration resulted in a higher delivered drug dose. The type of adapter used for pMDI actuation influenced drug delivery, with the highest dose observed using the CombiHaler.
Down-Regulation of Photosynthetic Electron Transport and Decline in CO2 Assimilation under Low Frequencies of Pulsed Lights
Authors: Cinq-Mars Marguerite , Samson Guy
Published: September 2021

The decline in CO2 assimilation in leaves exposed to decreasing frequencies of pulsed light is well characterized, in contrast to the regulation of photosynthetic electron transport under these conditions. Thus, we exposed sunflower leaves to pulsed lights of different frequencies but with the same duty ratio (25%) and averaged light intensity (575 μmoles photons m−2 s−1). The rates of net photosynthesis Pn were constant from 125 to 10 Hz, and declined by 70% from 10 to 0.1 Hz. This decline coincided with (1) a marked increase in nonphotochemical quenching (NPQ), and (2) the completion after 25 ms of illumination of the first phase of P700 photooxidation, the primary electron donor of PSI. Under longer light pulses (<5 Hz), there was a slower and larger P700 photooxidation phase that could be attributed to the larger NPQ and to a resistance of electron flow on the PSI donor side indicated by 44% slower kinetics of a P700+ dark reduction. In addition, at low frequencies, the decrease in quantum yield of photochemistry was 2.3-times larger for PSII than for PSI. Globally, our results indicate that the decline in CO2 assimilation at 10 Hz and lower frequencies coincide with the formation of NPQ and a restriction of electron flows toward PSI, favoring the accumulation of harmless P700+.
Genome-Wide Analysis, Modeling, and Identification of Amino Acid Binding Motifs Suggest the Involvement of GH3 Genes during Somatic Embryogenesis of Coffea canephora
Authors: Méndez-Hernández Hugo A. , Quintana-Escobar Ana O. , Uc-Chuc Miguel A. , Loyola-Vargas Víctor M.
Published: September 2021

Auxin plays a central role in growth and plant development. To maintain auxin homeostasis, biological processes such as biosynthesis, transport, degradation, and reversible conjugation are essential. The Gretchen Hagen 3 (GH3) family genes codify for the enzymes that esterify indole-3-acetic acid (IAA) to various amino acids, which is a key process in the induction of somatic embryogenesis (SE). The GH3 family is one of the principal families of early response to auxin genes, exhibiting IAA-amido synthetase activity to maintain optimal levels of free auxin in the cell. In this study, we carried out a systematic identification of the GH3 gene family in the genome of Coffea canephora, determining a total of 18 CcGH3 genes. Analysis of the genetic structures and phylogenetic relationships of CcGH3 genes with GH3 genes from other plant species revealed that they could be clustered in two major categories with groups 1 and 2 of the GH3 family of Arabidopsis. We analyzed the transcriptome expression profiles of the 18 CcGH3 genes using RNA-Seq analysis-based data and qRT-PCR during the different points of somatic embryogenesis induction. Furthermore, the endogenous quantification of free and conjugated indole-3-acetic acid (IAA) suggests that the various members of the CcGH3 genes play a crucial role during the embryogenic process of C. canephora. Three-dimensional modeling of the selected CcGH3 proteins showed that they consist of two domains: an extensive N-terminal domain and a smaller C-terminal domain. All proteins analyzed in the present study shared a unique conserved structural topology. Additionally, we identified conserved regions that could function to bind nucleotides and specific amino acids for the conjugation of IAA during SE in C. canephora. These results provide a better understanding of the C. canephora GH3 gene family for further exploration and possible genetic manipulation.