bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluating the Privacy and Utility of Time-Series Data Perturbation Algorithms
Authors: Roman Adrian-Silviu
Published: March 2023

Data collected from sensor-rich systems may reveal user-related patterns that represent private information. Sensitive patterns from time-series data can be protected using diverse perturbation methods; however, choosing the method that provides the desired privacy and utility level is challenging. This paper proposes a new procedure for evaluating the utility and privacy of perturbation techniques and an algorithm for comparing perturbation methods. The contribution is significant for those involved in protecting time-series data collected from various sensors as the approach is sensor-type-independent, algorithm-independent, and data-independent. The analysis of the impact of data integrity attacks on the perturbed data follows the methodology. Experimental results obtained using actual data collected from a VW Passat vehicle via the OBD-II port demonstrate the applicability of the approach to measuring the utility and privacy of perturbation algorithms. Moreover, important benefits have been identified: the proposed approach measures both privacy and utility, various distortion and perturbation methods can be compared (no matter how different), and an evaluation of the impact of data integrity attacks on perturbed data is possible.
Multi de Bruijn Sequences and the Cross-Join Method
Authors: Alhakim Abbas , Szmidt Janusz
Published: March 2023

We show a method to construct binary multi de Bruijn sequences using the cross-join method. We extend the proof given by Alhakim for ordinary de Bruijn sequences to the case of multi de Bruijn sequences. In particular, we establish that all multi de Bruijn sequences can be obtained by cross-joining an ordinary de Bruijn sequence concatenated with itself an appropriate number of times. We implemented the generation of all multi de Bruijn sequences of type C(2,2,2) and C(3,2,2). We experimentally confirm that some multi de Bruijn sequences can be generated by Galois Nonlinear Feedback Shift Registers (NLFSRs). It is supposed that all multi de Bruijn sequences can be generated using Galois NLFSRs.
Significance of Nanoparticle Radius and Gravity Modulation on Dynamics of Nanofluid over Stretched Surface via Finite Element Simulation: The Case of Water-Based Copper Nanoparticles
Authors: Ali Bagh , Shafiq Anum , Alanazi Meznah M. , Hendi Awatif A. , Hussein Ahmed Kadhim , Shah Nehad Ali
Published: March 2023

This communication studies the importance of varying the radius Dp of Copper nanoparticles for microgravity-modulated mixed convection in micropolar nanofluid flux under an inclined surface subject magnetic field and heat source. In the current era, extremely pervasive modernized technical implementations have drawn attention to free convection governed by g-jitter force connected with microgravity. Therefore, fixed inter-spacing of nanoparticles and effects of g-jitter on the inclined surface are taken into consideration. A mathematical formulation based on conservation principles was non-dimensionalized by enforcement of similarity transformation, yielding a related set of ODEs. The convective non-linearity and coupling, an FE discretization, was implemented and executed on the Matlab platform. The numerical process’ credibility was ensured for its acceptable adoption with the defined outcomes. Then, the computational endeavor was continued to elucidate the impacts of various inputs of Dp, the amplitude of modulation ϵ, material parameter β, mixed convection parameter λ, inclination angle γ, and magnetic parameter M. The enlarging size of nanoparticles accelerated the nanofluid flow due to the depreciation of viscosity and receded the fluid temperature by reducing the surface area for heat transportation. The modulated Nusselt number, couple stress, and skin friction coefficient are significantly affected by the variation of Dp, M, β, λ, and ϵ. These results would benefit experts dealing with upper space transportation and materials’ performance, such as the effectualness of chemical catalytic reactors and crystals.
The Effect of SGLT2 Inhibitors on the Development of Contrast-Induced Nephropathy in Diabetic Patients with Non-ST Segment Elevation Myocardial Infarction
Authors: Özkan Uğur , Gürdoğan Muhammet
Published: March 2023

Background and Objectives: Percutaneous procedures using contrast agents are modern diagnosis and treatment methods for cardiovascular diseases. Contrast use may cause nephropathy, especially in diabetic patients. SGLT2 inhibitors have strong cardioprotective and renal protective effects. In our study, we investigated the effectiveness of this drug group in preventing the development of Contrast-Induced Nephropathy (CIN). Materials and Methods: The results of 312 diabetic patients who underwent CAG were analyzed. The study group included 104 DM patients using SGLT2 and the control group did not use SGLT2. These groups were compared with each other in terms of clinical, demographic, and laboratory parameters. Results: The groups were similar characteristics. However, post-CAG creatinine values compared with before the procedure, the development of CIN was observed to be significantly less in the group using SGLT2 inhibitor (p = 0.03). When the results of the multivariate analysis were examined, it was seen that the use of SGLT2 inhibitors significantly reduced the risk of CIN (odds ratio (OR): 0.41, 95% confidence interval (CI): 0,142–0.966, p = 0.004). Conclusions: Our study showed that SGLT2 inhibitors may be protective against the development of CIN, especially in patients with comorbid conditions such as diabetes.
Digital Form for Assessing Dentistry Undergraduates Regarding Periodontal Disease Associated with Cardiovascular Diseases
Authors: Medeiros Rebeca Antunes de , Silva Yngrid Monteiro da , Miranda Yasmim Marçal Soares , Gomes Danyelle de Sousa , Carvalho Tabata Resque Beckmann , Tanaka Erich Brito , Oliveira Paula Gabriela Faciola Pessôa de , Nogueira Jorge Sá Elias , Menezes Silvio Augusto Fernandes de , Menezes Tatiany Oliveira de Alencar , Laurentino Rogério Valois , Fonseca Ricardo Roberto de Souza , Machado Luiz Fernando Almeida
Published: March 2023

Background: Throughout recent years, periodontal disease (PD) has been linked to innumerable medical systemic conditions, such as cardiovascular disease (CVD). This association could negatively impact oral health, so the knowledge of dentists who have graduated must follow modern dentistry in order to promote oral health, mainly in systemically compromised patients. Therefore, the present study aimed to determine and evaluate the knowledge level of dentistry undergraduate students (DUS) regarding the correct periodontal treatment and management of cardiac patients with PD. Methods: This cross-sectional and populational-based study was conducted between March and June 2022 in northern Brazil. A total of 153 DUS received an anonymous digital form (Google Forms Platform) using a non-probabilistic “snowball” sampling technique. The digital form was composed of four blocks of dichotomous and multiple-choice questions. After signing the informed consent term, DUS were divided into three groups according to their period/semester in dentistry graduation during the study time (G1: 1st period/semester; G2: 5th period/semester and G3: 10th period/semester). A total of 25 questions referring to demographic, educational and knowledge data about the dental and periodontal care of cardiac patients with PD were asked, and all data were presented as descriptive percentages and then analyzed using the Kappa test. Results: From a total of 153 (100%) DUS, the sample was mostly composed of 104 (68%) female participants, with an average age of 21.1 years. Regarding basic knowledge, the majority of answers were no, with G1 being higher than G2 and G3. Regarding clinical questions, 1247 (58.3%) answers were no. Additionally, regarding fundamental clinical questions 1, 2, 3, 7, 9, 11, 13 and 14, the majority of G1, G2 and G3 answered no, demonstrating a major lack of knowledge. Conclusions: In our study, DUS demonstrated a low knowledge level of the dental and periodontal care of cardiac patients with PD and its bi-directional link. Thus, according to our results, an improvement in dentistry educational programs regarding periodontal medicine must be implemented.
Nephrotic Syndrome and Statin Therapy: An Outcome Analysis
Authors: Busuioc Ruxandra , Ștefan Gabriel , Stancu Simona , Zugravu Adrian , Mircescu Gabriel
Published: March 2023

Background and Objectives: Hypercholesterolemia in patients with nephrotic syndrome (NS) may predispose to cardiovascular events and alter kidney function. We aimed to evaluate statins efficiency in NS patients under immunosuppression using four endpoints: remission rate (RR), end-stage kidney disease (ESKD), major cardiovascular events (MACE), and thrombotic complications (VTE). Materials and Methods: We retrospectively examined the outcome at 24 months after diagnosis of 154 NS patients (age 53 (39–64) years, 64% male, estimated glomerular filtration rate (eGFR) 61.9 (45.2–81.0) mL/min). During the follow-up, the lipid profile was evaluated at 6 months and at 1 and 2 years. Results: The median cholesterol level was 319 mg/dL, and 83% of the patients received statins. Patients without statins (17%) had similar age, body mass index, comorbidities, blood lipids levels, NS severity, and kidney function. The most used statin was simvastatin (41%), followed by rosuvastatin (32%) and atorvastatin (27%). Overall, 79% of the patients reached a form of remission, 5% reached ESKD, 8% suffered MACE, and 11% had VTE. The mean time to VTE was longer in the statin group (22.6 (95%CI 21.7, 23.6) versus 20.0 (95%CI 16.5, 23.5) months, p 0.02). In multivariate analysis, statin therapy was not associated with better RR, kidney survival, or fewer MACE; however, the rate of VTE was lower in patients on statins (HR 2.83 (95%CI 1.02, 7.84)). Conclusions: Statins did not improve the remission rate and did not reduce the risk of MACE or ESKD in non-diabetic nephrotic patients. However, statins seemed to reduce the risk of VTE. Further randomized controlled studies are needed to establish statins’ role in NS management.
DLC1 as Druggable Target for Specific Subsets of Gastric Cancer: An RNA-seq-Based Study
Authors: Yang Lianlei , Bhat Adil Manzoor , Qazi Sahar , Raza Khalid
Published: March 2023

Background: Gastric cancer has been ranked the third leading cause of cancer death worldwide. Its detection at the early stage is difficult because patients mostly experience vague and non-specific symptoms in the early stages. Methods: The RNA-seq datasets of both gastric cancer and normal samples were considered and processed. The obtained differentially expressed genes were then subjected to functional enrichment analysis and pathway analysis. An implicit atomistic molecular dynamics simulation was executed on the selected protein receptor for 50 ns. The electrostatics, surface potential, radius of gyration, and macromolecular energy frustration landscape were computed. Results: We obtained a large number of DEGs; most of them were down-regulated, while few were up-regulated. A DAVID analysis showed that most of the genes were prominent in the KEGG and Reactome pathways. The most prominent GAD disease classes were cancer, metabolic, chemdependency, and infection. After an implicit atomistic molecular dynamics simulation, we observed that DLC1 is electrostatically optimized, stable, and has a reliable energy frustration landscape, with only a few maximum energy frustrations in the loop regions. It has a good functional and binding affinity mechanism. Conclusions: Our study revealed that DLC1 could be used as a potential druggable target for specific subsets of gastric cancer.
X-ray-Fluorescence-Based Screening Method for Uranium in Contaminated Brackish Water Using Graphene Oxide Nanosheets
Authors: Yoshii Hiroshi , Takamura Kodai , Uwatoko Tetsuaki , Sakai Yasuhiro
Published: March 2023

In the event of uranium release into the environment due to an accident, confirming the presence of uranium contamination is difficult because uranium is a naturally occurring element. In this study, we developed a method based on X-ray fluorescence (XRF) for the facile screening of uranium in brackish water samples in the event of an accident in a coastal area. Graphene oxide nanosheets were added to uncontaminated brackish water sampled from different sites to adsorb the uranium present in the samples, if any. The graphene oxide nanosheets were then collected using a membrane filter and analyzed using XRF. The results revealed that the signal intensity of the U Lα peak was proportional to the salinity. Hence, uranium contamination could be confirmed when the intensity of the U Lα peak was significantly greater than that derived from the background uranium content, as estimated from the salinity value. Thus, in the event of an accident, the salinity of the collected brackish water should be measured, and XRF analysis should be performed using our developed method. This method is useful for screening brackish water for uranium contamination.
Efficient Recovery of Organic Matter from Municipal Wastewater by a High-Rate Membrane Bioreactor Equipped with Flat-Sheet Ceramic Membranes
Authors: Rocco Michael Joseph , Hafuka Akira , Tsuchiya Toru , Kimura Katsuki
Published: March 2023

High-rate processes have been investigated for the recovery of organic matter from municipal wastewater. High-rate membrane bioreactors (HR-MBRs) may simultaneously achieve the increased recovery of carbon and high effluent quality, although control of membrane fouling is extremely difficult. To address the severe fouling in HR-MBRs, the combination of granular scouring and frequent chemically enhanced backwashing was examined. The use of robust flat-sheet ceramic membranes enabled the application of those cleaning strategies. Experiments were carried out at an existing wastewater treatment plant. To operate as a high-rate system, the bioreactor solid residence time and hydraulic residence time were set at 0.5 days and 1.6 h, respectively. Although a relatively high flux of 20 L m−2 h−1 was applied, the proposed HR-MBR exhibited a very low fouling rate of 1.3 kPa/day. The system could recover >70% of the carbon from raw wastewater, whereas the concentration of chemical oxygen demand in the effluent was lowered to <20 mg/L. The performance of the proposed HR-MBR observed in this study was clearly superior to those reported in previous related studies.
A Study on the Synthesis and Proton Transport Behavior of Multilayered ZSM-5 Zeolite Nanosheet Membranes Laminated on Polymer Substrates
Authors: Cao Zishu , Iskhakova Landysh , Sun Xinhui , Dong Junhang
Published: March 2023

Single crystalline ZSM-5 ZNs with thicknesses around 6 nm were obtained by secondary growth of silicalite nanoparticles using diquaternary bis-1,5(tripropyl ammonium) pentamethylene diiodide (dC5) as a structure-directing agent (SDA). The dC5 could be effectively removed from the ZN pores by either high-temperature calcination or UV irradiation in air at room temperature but not by the piranha solution treatment. Ultrathin ZN-laminated membranes (ZNLMs) were fabricated by sandwiching a UV-activated multilayered ZN film between two recast Nafion® layers (ZNLM-Nafion) and by filtration coating from a suspension of thermally activated ZNs on a nonionic porous PVDF (ZNLM-PVDF). The ZNLMs on both supports demonstrated the ability of highly proton-selective ion conduction with low resistances in aqueous electrolyte solutions. The ZNLM-PVDF with PVDF binder was structurally stable, and it achieved a comparably low ASR but much higher proton selectivity compared with a Nafion membrane of same overall thickness. However, detachment between the ZNLM and Nafion layers occurred when the ZNLM-Nafion operated in aqueous electrolyte solutions. Results of this study show the potential for developing ZNLMs as efficient proton-conducting membranes without using expensive ionic polymer matrices. However, the development of polymer-supported ZNLMs is hindered by the current inefficiency in preparing well-dispersed suspensions of open-pore ZNs. Future development of efficient methods for synthesizing open-pore ZNs in dispersed states is key to realizing high-performance ZNLMs on polymers.
Effect of Laser Shock Peening on the Stress Corrosion Cracking of 304L Stainless Steel
Authors: Yoo Young-Ran , Choi Seung-Heon , Kim Young-Sik
Published: March 2023

Storage canisters used in nuclear power plants operating in seaside areas—where the salt content in the atmosphere is high—may be susceptible to chloride-induced stress corrosion cracking (CISCC). Chloride-induced stress corrosion cracking is one of the ways in which dry storage canisters made of stainless steel can degrade. Stress corrosion cracking depends on the microstructure and residual stress, and it is therefore very important to improve the surface properties of materials. Laser shock peening both greatly deforms the material surface and refines grains, and it generates compressive residual stress in the deep part from the surface of the material. This study focused on the effect of laser shock peening on the stress corrosion cracking of 304L stainless steel. The laser shock peening was found to induce compressive residual stress from the surface to a 1 mm depth, and the SCC properties were evaluated by a U-bend test. The results showed that the SCC resistance of laser-peened 304L stainless steel in a chloride environment was enhanced, and that it was closely related to grain size, the pitting potential of the cross section, and residual stress.
In Situ Observation of Solidification and Crystallization of Low-Alloy Steels: A Review
Authors: Wang Yong , Wang Qiang , Mu Wangzhong
Published: March 2023

Crystallization during the solidification process of steels is of vital importance for controlling the quality of final products. This paper summarizes the in situ characterization research activities of crystallization behaviors of low-alloy steels during the solidification process. The results obtained using high-temperature confocal laser scanning microscope (HT-CLSM) are critically reviewed, and other relevant methodologies, i.e., either classical method using differential scanning calorimetry (DSC) or large-scale facility (LSF), are also briefly mentioned. The evolution of the crystallization front from a planar to a cellular and further to a dendritic one, and subsequential microstructure evolutions, i.e., delta-ferrite (δ) formation from the liquid, austenite (γ) transformation and decomposition, are mainly discussed. The current review aims to highlight the state-of-the-art research outputs obtained by the novel in situ characterization techniques, and the obtained knowledge aims to shed light on the further development of the quality low-alloy steel products by controlling the processing and structure correlation.
Research on Grain Refinement of Sc and Zr Addition in an Al-Mg-Zn Alloy from Experiments and First-Principles Calculations
Authors: Zhang Tianyou , Yan Lizhen , Li Xiwu , Xiao Wei , Gao Guanjun , Li Zhihui , Zhang Yongan , Xiong Baiqing
Published: March 2023

The effect of trace Sc and Zr on grain refinement of Al-5.0Mg-3.0Zn as-cast alloy was investigated by optical microscopy and scanning electron microscopy with EDS. The results indicated that the critical quantities of Sc and Zr for Al-Mg-Zn alloy to produce a significant refining effect were determined and the total mass fraction of Sc and Zr was not less than 0.27, and the mass fraction of Sc was more than 0.13. The average grain size of the as-cast alloy ranged from 30 to 44 μm. The as-cast microstructure refinement of the alloy was related to the number density of Al3(Sc, Zr) particles and the critical nucleation work of grains. Furthermore, based on first-principles calculations, the formation enthalpies of different Al3(Sc, Zr) particles and the interface stabilities have been theoretically discussed. The experimental phenomenon of increasing the particle number by the simultaneous addition of Sc and Zr was well explained. Thus, this investigation presented a better insight into the grain refining mechanism from experiments and theoretical calculations.
The Effect of PEO Treatment in a Ta-Rich Electrolyte on the Surface and Corrosion Properties of Low-Carbon Steel for Potential Use as a Biomedical Material
Authors: Marcuz Nádia , Ribeiro Rafael , Rangel Elidiane , da Cruz Nilson , Correa Diego
Published: March 2023

Fe-based materials have extensive applications in the building and automobile industries due to their excellent mechanical properties and low cost. However, their biomedical employment is restricted by the corrosion propensity when in contact with bodily fluids. In this study, single-step Plasma Electrolytic Oxidation, PEO, treatment in Ta-rich electrolyte was used, for the first time, to improve the corrosion resistance of low-carbon steel SAE 1020 for possible use as device implants. The effect of the applied voltage on the chemical and phase composition, topography, wettability, roughness, and corrosion properties were addressed. The results indicated that the Fe-based oxide coatings had a rough and hydrophilic surface, increasing the Ta content with the applied potential. The phase composition of the coatings was mainly composed of hematite (Fe2O3), with the Fourier-transform Infrared Spectroscopy, FTIR, spectrums indicating the presence of some absorbed water and organic molecules. The corrosion resistance of the PEO-treated samples was better than the substrate against saline solution (0.9% NaCl) due to the Fe2O3 growth decorated with Ta particles, especially the sample treated at 200 V. The results state that Ta-enriched Fe-based oxide coatings could significantly improve the applicability of low-carbon steel SAE 1020 as a low-cost biomaterial, particularly for medical devices.
Microstructural and Mechanical Properties of Longitudinal Welds in Porthole Die Extrudates of a 0.5 wt.% GNP/Al Composite
Authors: Lou Shumei , Li Yiming , Cheng Baojia , Ran Lingwei , Bai Xuefeng , Chen Peng , Wang Qingbiao
Published: March 2023

In this study, porthole die extrusion was performed on a graphene-nanoplatelet-reinforced aluminum composite (0.5 wt.% GNP/Al) prepared by powder metallurgy. The microstructure, grain size, microtexture, and mechanical properties of the composite extruded by the porthole die were studied. Along the extrusion direction, the tensile strength of the extruded composite was 139.7 MPa, and the elongation was 27.1%. Along the transverse direction, which included the weld zone, the tensile strength was 126.4 MPa, and the elongation was 24.1%. These values were 6.65% and 54.63% higher than those obtained for pure aluminum, respectively. Fractography along the extrusion direction revealed obvious ductile fracture characteristics; however, these were not so obvious along the transverse direction, mainly due to the anisotropy caused by the grain orientation of the extruded composite, thereby indicating that the composite exhibited excellent weld performance, which was further verified by Optical Microscope, Electron Backscattered Diffraction, and Transmission Electron Microscopeimages. Overall, these results indicate that GNP can contribute to the strength and toughness of composites in the weld zone in porthole die extrusions.
Yield Surfaces and Plastic Potentials for Metals, with Analysis of Plastic Dilatation and Strength Asymmetry in BCC Crystals
Authors: Zubelewicz Aleksander , Clayton John D.
Published: March 2023

Since the 1980s, constitutive modeling has steadily migrated from phenomenological descriptions toward approaches that are based on micromechanics considerations. Despite significant efforts, crystal plasticity remains an open field of research. Among the unresolved issues are the anomalous behavior of metals at low temperatures and the stress upturn at extreme dynamics. This work is focused on the low-temperature responses of body-centered-cubic (bcc) metals, among them, molybdenum (Mo). At these conditions, the plastic flow strength is governed by the motion of screw dislocations. The resultant non-planarity of core structures and slip causes the following: the shear stress includes non-glide components, the Schmid law is violated, there is a tension-compression asymmetry, and the yield surface and plastic potential are clearly decoupled. We find that the behavioral complexities can be explained by atomistically resolved friction coefficients in macroscopic yield and flow. The plastic flow mechanisms establish the departure point into the follow-up analysis of yield surfaces. For example, we know that while the von Mises stress is explained based on energy considerations, we will also show that the stress has a clear geometric interpretation. Moreover, the von Mises stress is just one case within a much broader class of equivalent stresses. Possible correlations among non-Schmid effects (as represented macroscopically by friction coefficients), volume change (i.e., residual elastic dilatation) from dislocation lines, and elastic anisotropy are investigated. Extensions to the shock regime are also established.
A Study of the Metallurgical and Mechanical Properties of Friction-Stir-Welded Pure Titanium
Authors: Regev Michael , Almoznino Benny , Spigarelli Stefano
Published: March 2023

Commercially pure titanium (CP-Ti) plates were friction-stir welded (FSWed) using a welding tool with a tungsten carbide (WC) pin. The bead-on-plate technique was applied to reduce the effects of welding defects, such as incomplete penetration. An X-ray inspection and fractography showed that the FSWed material was free of defects and of WC particles, which may have originated from the welding tool. The appearance of refined equiaxed grains in the thermo-mechanically affected zone (TMAZ) may have been related to dynamic recrystallization (DRX) occurring during the FSW due to the high temperature and intensive plastic deformation involved in the process. Grain refinement, mechanical twinning, and increased dislocation density were detected within the TMAZ, and these microstructural changes were considered to be responsible for the improved mechanical properties of the TMAZ. The TEM study reported in the current paper revealed the presence of nano-sized grains in the FSWed material due to dynamic recrystallization (DRX) occurring during the processing stage. The microstructure obtained during FSW of Ti has been reported in a several publications, yet many discrepancies can be found in these publications. Among these discrepancies are the size and the shape of the grains at the various zones, as well as the presence or non-presence of various zones at the vicinity of the weld. The current study contradicts the argument for correlations between the conditions prevailing at different points across the TMAZ and microstructural changes, which were previously proposed by several researchers.
Short-Flow Rolling Process and Heat Treatment of Seamless Titanium Alloy Tube
Authors: Chen Chen , Chen Jianxun , Shuang Yuanhua , Li Chao
Published: March 2023

In view of the material characteristics of titanium alloys, such as their capability to quickly cool down and their poor machinability, in this study, we combined a new production mode for seamless tube rolling (tandem skew rolling, TSR) with titanium alloy materials and conducted systematic research. The most suitable parameters for titanium alloy rolling were determined from the unit parameters using finite-element software and an analysis of the changing laws of stress-strain, temperature, speed and tension during the rolling process. A rolling experiment was completed in the tandem skew rolling unit. Seamless titanium alloy (TC4ELI) tubes with uniform wall thickness were successfully produced and a metallurgical heat-treatment experiment was carried out. The results show that the seamless titanium alloy tubes prepared using the TSR process have a high degree of dimensional precision (the outer diameter is approximately 38.7 mm, the wall thickness is approximately 3.9 mm and the axial extension is 2.9 times) and the tube after heat treatment still presented a basketweave structure. Furthermore, the hardness level of the seamless titanium alloy tubes was improved. It can be concluded that the TSR process with a short flow is suitable for the mass production of seamless titanium alloy tubes.
Metabolomics in Corneal Diseases: A Narrative Review from Clinical Aspects
Authors: Teo Alvin Wei Jun , Zhang Jingwen , Zhou Lei , Liu Yu-Chi
Published: March 2023

Corneal pathologies may have subtle manifestations in the initial stages, delaying diagnosis and timely treatment. This can lead to irreversible visual loss. Metabolomics is a rapidly developing field that allows the study of metabolites in a system, providing a complementary tool in the early diagnosis and management of corneal diseases. Early identification of biomarkers is key to prevent disease progression. The advancement of nuclear magnetic resonance and mass spectrometry allows the identification of new biomarkers in the analysis of tear, cornea, and aqueous humor. Novel perspectives on disease mechanisms are identified, which provide vital information for potential targeted therapies in the future. Current treatments are analyzed at a molecular level to offer further information regarding their efficacy. In this article, we provide a comprehensive review of the metabolomic studies undertaken in the cornea and various pathologies such as dry eye disease, Sjogren’s syndrome, keratoconus, post-refractive surgery, contact lens wearers, and diabetic corneas. Lastly, we discuss the exciting future that metabolomics plays in cornea research.
NMR-Based Metabolomics Reveals Effects of Water Stress in the Primary and Specialized Metabolisms of Bauhinia ungulata L. (Fabaceae)
Authors: Borim de Souza Ana Júlia , Ocampos Fernanda Maria Marins , Catoia Pulgrossi Rafael , Dokkedal Anne Lígia , Colnago Luiz Alberto , Cechin Inês , Saldanha Luiz Leonardo
Published: March 2023

Bauhinia ungulata is a plant used in Brazilian traditional medicine for the treatment of diabetes. Phytochemical studies revealed flavonoids and the saccharide pinitol related to hypoglycemic activity of the Bauhinia species. To determine the effects of water deficit on ecophysiological parameter and metabolite fingerprints of B. ungulata, specimens were treated with the following water regimens under greenhouse conditions: daily watering (control), watering every 7 days (group 7D), and watering every 15 days (group 15D). Metabolite profiling of the plants subjected to water deficit was determined by LC-HRMS/MS. An NMR-based metabolomics approach applied to analyze the extracts revealed increased levels of known osmoprotective and bioactive compounds, such as D-pinitol, in the water deficit groups. Physiological parameters were determined by gas exchange in planta analysis. The results demonstrated a significant decrease in gas exchange under severe drought stress, while biomass production was not significantly different between the control and group 7D under moderate stress. Altogether, the results revealed that primary and specialized/secondary metabolism is affected by long periods of severe water scarcity downregulating the biosynthesis of bioactive metabolites such as pinitol, and the flavonoids quercetin and kaempferol. These results may be useful for guiding agricultural production and standardizing medicinal herb materials of this medicinal plant.
Melatonin versus Sleep Deprivation for Sleep Induction in Nap Electroencephalography: Protocol for a Prospective Randomized Crossover Trial in Children and Young Adults with Epilepsy
Authors: Varesio Costanza , Franco Valentina , Pasca Ludovica , Celario Massimiliano , Fattore Cinzia , Fedele Guido , Rota Paola , Palmisani Michela , De Giorgis Valentina
Published: March 2023

Electroencephalography (EEG) continues to be a pivotal investigation in children with epilepsy, providing diagnostic evidence and supporting syndromic classification. In the pediatric population, electroencephalographic recordings are frequently performed during sleep, since this procedure reduces the number of artifacts and activates epileptiform abnormalities. To date, no shared guidelines are available for sleep induction in EEG. Among the interventions used in the clinical setting, melatonin and sleep deprivation represent the most used methods. The main purpose of this study is to test the non-inferiority of 3–5 mg melatonin versus sleep deprivation in achieving sleep in nap electroencephalography in children and young adult patients with epilepsy. To test non-inferiority, a randomized crossover trial is proposed where 30 patients will be randomized to receive 3–5 mg melatonin or sleep deprivation. Each enrolled subject will perform EEG recordings during sleep in the early afternoon for a total of 60 EEGs. In the melatonin group, the study drug will be administered a single oral dose 30 min prior to the EEG recording. In the sleep deprivation group, parents will be required to subject the child to sleep deprivation the night before registration. Urinary and salivary concentrations of melatonin and of its main metabolite 6-hydroxymelatonin will be determined by using a validated LC-MS method. The present protocol aims to offer a standardized protocol for sleep induction to be applied to EEG recordings in those of pediatric age. In addition, melatonin metabolism and elimination will be characterized and its potential interference in interictal abnormalities will be assessed.
Thermogenic Capacity of Human Supraclavicular Brown Fat and Cold-Stimulated Brain Glucose Metabolism
Authors: U-Din Mueez , Rebelos Eleni , Saari Teemu , Niemi Tarja , Kuellmer Katharina , Eskola Olli , Fromme Tobias , Rajander Johan , Taittonen Markku , Klingenspor Martin , Nuutila Pirjo , Nummenmaa Lauri , Virtanen Kirsi A.
Published: March 2023

Human brain metabolism is susceptible to temperature changes. It has been suggested that the supraclavicular brown adipose tissue (BAT) protects the brain from these fluctuations by regulating heat production through the presence of uncoupling protein 1 (UCP-1). It remains unsolved whether inter-individual variation in the expression of UCP-1, which represents the thermogenic capacity of the supraclavicular BAT, is linked with brain metabolism during cold stress. Ten healthy human participants underwent 18F-FDG PET scanning of the brain under cold stimulus to determine brain glucose uptake (BGU). On a separate day, an excision biopsy of the supraclavicular fat—the fat proximal to the carotid arteries supplying the brain with warm blood—was performed to determine the mRNA expression of the thermogenic protein UCP-1. Expression of UCP-1 in supraclavicular BAT was directly related to the whole brain glucose uptake rate determined under cold stimulation (rho = 0.71, p = 0.03). In sub-compartmental brain analysis, UCP-1 expression in supraclavicular BAT was directly related to cold-stimulated glucose uptake rates in the hypothalamus, medulla, midbrain, limbic system, frontal lobe, occipital lobe, and parietal lobe (all rho ≥ 0.67, p < 0.05). These relationships were independent of body mass index and age. When analysing gene expressions of BAT secretome, we found a positive correlation between cold-stimulated BGU and DIO2. These findings provide evidence of functional links between brain metabolism under cold stimulation and UCP-1 and DIO2 expressions in BAT in humans. More research is needed to evaluate the importance of these findings in clinical outcomes, for instance, in examining the supporting role of BAT in cognitive functions under cold stress.
Integrated Omics Approach to Discover Differences in the Metabolism of a New Tibetan Desmodesmus sp. in Two Types of Sewage Treatments
Authors: Wang Jinhu , Chen Junyu , Zhang Dongdong , Cui Xiaomei , Zhou Jinna , Li Jing , Wei Yanli , Bu Duo
Published: March 2023

Microalgae are now widely applied in municipal (YH_3) and industrial sewage (YH_4) treatments. Through integrated omics analysis, we studied the similarities and differences at the molecular level between the two different types of sewage treatment processes. The most significantly enriched gene ontology (GO) terms in both types of sewage treatments were the ribosome, photosynthesis, and proteasome pathways. The results show that the pathways of differentially expressed genes (DEGs) and differentially accumulated metabolites (DAMs) were enriched for photosynthesis, glyoxylate and dicarboxylate metabolism, and carbon fixation in photosynthetic organisms. Considering YH_3 vs. YH_4, the metabolism of citrate, sedoheptulose-7P, and succinate was significantly upregulated. In addition, the results showed that the pathways of DEGs and DAMs were enriched in terms of amino acid metabolism and carotenoid biosynthesis in YH_4 vs. YH_3. The metabolism of S-Adenosyl-L-homocysteine was significantly downregulated, 2-oxobutanoate was significantly upregulated and downregulated, and the metabolism of abscisic acid glucose ester (ABA-GE) was also significantly upregulated. Overall, the results of this paper will help to improve the basic knowledge of the molecular response of microalgae to sewage treatments, and help design a response strategy based on microalgae for complex, mixed sewage treatments.
Mechanical Reliability Assessment of a Flexible Package Fabricated Using Laser-Assisted Bonding
Authors: Le Xuan-Luc , Le Xuan-Bach , Hwangbo Yuhwan , Joo Jiho , Choi Gwang-Mun , Eom Yong-Sung , Choi Kwang-Seong , Choa Sung-Hoon
Published: March 2023

The aim of this study was to develop a flexible package technology using laser-assisted bonding (LAB) technology and an anisotropic solder paste (ASP) material ultimately to reduce the bonding temperature and enhance the flexibility and reliability of flexible devices. The heat transfer phenomena during the LAB process, mechanical deformation, and the flexibility of a flexible package were analyzed by experimental and numerical simulation methods. The flexible package was fabricated with a silicon chip and a polyimide (PI) substrate. When the laser beam was irradiated onto the flexible package, the temperatures of the solder increased very rapidly to 220 °C, high enough to melt the ASP solder, within 2.4 s. After the completion of irradiation, the temperature of the flexible package decreased quickly. It was found that the solder powder in ASP was completely melted and formed stable interconnections between the silicon chip and the copper pads, without thermal damage to the PI substrate. After the LAB process, the flexible package showed warpage of 80 μm, which was very small compared to the size of the flexible package. The stress of each component in the flexible package generated during the LAB process was also found to be very low. The flexible device was bent up to 7 mm without failure, and the flexibility can be improved further by reducing the thickness of the silicon chip. The bonding strength and environmental reliability tests also showed the excellent mechanical endurance of the flexible package.
Effects of Coconut Oil and Palm Oil on Growth, Rumen Microbiota, and Fatty Acid Profile of Suckling Calves
Authors: Hu Fengming , Piao Minyu , Yang Chuntao , Diao Qiyu , Tu Yan
Published: March 2023

This study aimed to evaluate the effects of coconut oil and palm oil in milk replacer (MR) on the growth performance, blood lipids, rumen fermentation, rumen microbiota, and fatty acid profile of hepatic and muscle of suckling calves. Thirty-six Holstein male calves were randomly assigned to three treatments. Three milk replacers containing different fat sources were as follows: control group (CON, milk fat), coconut oil group (CCO, coconut oil powder as fat), and palm oil group (PLO, palm oil powder as fat). Calves were weighed and blood sampled at 14, 28, 42, and 56 days old, respectively, and the feed intake and fecal score were recorded daily. Fat sources in milk replacers had no effects on body weight, ADG, DMI, fecal score, or days of abnormal fecal in suckling calves among the three groups, while the PLO group tended to decrease starter intake compared with the other groups. Serum concentrations of TC, HDL-C, LDL-C, and VLDL-C in the CCO group increased compared with those of the CON group. Palm oil also decreased the serum GLU concentration of calves but had no effects on serum lipids compared with milk fat. Coconut oil or palm oil had no effects on rumen fermentation, rumen chyme enzyme activity, rumen bacterial community richness and diversity, and dominant phyla and genera when compared with milk fat. However, compared with the CON group, the CCO group increased the proportion of MCFAs and n-6 PUFAs, and decreased the proportion of UFAs and MUFAs in liver tissue, while the PLO group increased the proportion of PUFAs and decreased the proportion of n-3 PUFAs in liver tissue. In addition, compared with the CON group, the CCO group increased the proportion of MCFAs, and decreased the proportion of UFAs and n-3 PUFAs in longissimus dorsi, while the PLO group increased the proportion of PUFAs and decreased the proportion of n-3 PUFAs in longissimus dorsi. In conclusion, compared with milk fat, coconut oil or palm oil in MR had no effects on growth performance, rumen fermentation, and rumen microflora but significantly increased serum lipids concentration and changed some proportions of MCFAs and PUFAs in liver and longissimus dorsi in suckling calves. These results indicate that coconut oil or palm oil as the sole fat source for MRs has no adverse effect on calf rumen fermentation and rumen microbiota but has a detrimental effect on n-3 PUFAs deposition in the liver and longissimus dorsi muscle.
Multi-Species Probiotic Strain Mixture Enhances Intestinal Barrier Function by Regulating Inflammation and Tight Junctions in Lipopolysaccharides Stimulated Caco-2 Cells
Authors: Han Hyeontak , You Yeji , Cha Soyoung , Kim Tae-Rahk , Sohn Minn , Park Jeseong
Published: March 2023

Although leaky gut syndrome is not recognized as an official diagnosis for human diseases, it is now believed that dysfunction of the cell barrier causes increased permeability of intestinal epithelial cells leading to this condition. Probiotics have been widely used to improve gut health, and studies have investigated the relevance of protecting the intestinal barrier by taking probiotic strains in vitro and in vivo. However, most studies have restricted the use of single or several probiotic strains and do not consider commercially available probiotic products composed of multi-species. In this study, we provide experimental evidence that a multi-species probiotic mixture composed of eight different strains and a heat-treated probiotic strain is effective in preventing leaky gut conditions. We employed an in vitro co-culture model system utilizing two different differentiated cell lines to mimic human intestinal tissue. The integrity of epithelial barrier function was protected by the preserving the occludin protein level and activating the AMPK signaling pathway, associated with tight junctions (TJs), through treatment with the probiotic strain mixture in Caco-2 cells. Moreover, we confirmed that application of the multi-species probiotic mixture reduced the expression of proinflammatory cytokine genes by inhibiting NFκB signaling pathway when artificial inflammation was induced in an in vitro co-culture model system. Finally, we proved that the epithelial permeability measured by trans-epithelial electrical resistance (TEER) was significantly decreased in the probiotic mixture treated cells, indicating that the integrity of the epithelial barrier function was not compromised. The multi-species probiotic strain mixture exhibited the protective effect on the integrity of intestinal barrier function via enhancing TJ complexes and reducing inflammatory responses in the human intestinal cells.
Lactobacillus salivarius WZ1 Inhibits the Inflammatory Injury of Mouse Jejunum Caused by Enterotoxigenic Escherichia coli K88 by Regulating the TLR4/NF-κB/MyD88 Inflammatory Pathway and Gut Microbiota
Authors: Wei Zhen , He Ziqi , Wang Tongyao , Wang Xiaoxuan , Wang Tiancheng , Long Miao
Published: March 2023

Replacing antibiotics with probiotics has become an important way to safely and effectively prevent and treat some gastrointestinal diseases. This study was conducted to investigate whether Lactobacillus salivarius WZ1 (L.S) could reduce the inflammatory injury to the mouse jejunum induced by Escherichia coli (ETEC) K88. Forty Kunming mice were randomly divided into four groups with 10 mice in each group. From day 1 to day 14, the control group and the E. coli group were administered with normal saline each day, while the L.S group and the L.S + E. coli group were gavaged with Lactobacillus salivarius WZ1 1 × 108 CFU/mL each day. On the 15th day, the E. coli group and the L.S + E. coli group were intragastrically administered ETEC K88 1 × 109 CFU/mL and sacrificed 24 h later. Our results show that pretreatment with Lactobacillus salivarius WZ1 can dramatically protect the jejunum morphological structure from the changes caused by ETEC K88 and relieve the morphological lesions of the jejunum, inhibiting changes in the mRNA expressions of TNF-α, IL-1β and IL-6 and the protein expressions of TLR4, NF-κB and MyD88 in the intestinal tissue of mice caused by ETEC K88. Moreover, pretreatment with Lactobacillus salivarius WZ1 also increased the relative abundance of beneficial genera such as Lactobacillus and Bifidobacterium and decreased the abundance of harmful genera such as Ralstonia and Helicobacter in the gut. These results demonstrate that Lactobacillus salivarius WZ1 can inhibit the inflammatory damage caused by ETEC K88 in mouse jejunum by regulating the TLR4/NF-κB/MyD88 inflammatory pathway and gut microbiota.
Genomic Investigation of Salmonella Typhi in Hong Kong Revealing the Predominance of Genotype 3.2.2 and the First Case of an Extensively Drug-Resistant H58 Genotype
Authors: Li Xin , Cao Huiluo , Chen Jonathan Hon-Kwan , Ng Yuey-Zhun , Fung Ka-Kin , Cheng Vincent Chi-Chung , Ho Pak-Leung
Published: March 2023

Typhoid fever is a notable disease in Hong Kong. We noticed two local cases of typhoid fever caused by Salmonella Typhi within a two-week period in late 2022, which had no apparent epidemiological linkage except for residing in the same region of Hong Kong. A phylogenetic study of Salmonella Typhi isolates from Hong Kong Island from 2020 to 2022 was performed, including a whole-genome analysis, the typing of plasmids, and the analysis of antibiotic-resistance genes (ARGs), to identify the dominant circulating strain and the spread of ARGs. A total of seven isolates, from six local cases and an imported case, were identified from positive blood cultures in two hospitals in Hong Kong. Five antibiotic-sensitive strains of genotype 3.2.2 were found, which clustered with another 30 strains originating from Southeast Asia. Whole-genome sequencing revealed clonal transmission between the two index cases. The remaining two local cases belong to genotype 2.3.4 and genotype 4.3.1.1.P1 (also known as the H58 lineage). The genotype 4.3.1.1.P1 strain has an extensively drug-resistant (XDR) phenotype (co-resistance to ampicillin, chloramphenicol, ceftriaxone, ciprofloxacin, and co-trimoxazole). Although the majority of local strains belong to the non-H58 genotype 3.2.2 with a low degree of antibiotic resistance, the introduction of XDR strains with the global dissemination of the H58 lineage remains a concern.