bluuebunny/crossref_metadata_2025 huggingface dataset:
A New Parallel Code Based on a Simple Piecewise Parabolic Method for Numerical Modeling of Colliding Flows in Relativistic Hydrodynamics
Authors: Kulikov Igor , Chernykh Igor , Karavaev Dmitry , Prigarin Vladimir , Sapetina Anna , Ulyanichev Ivan , Zavyalov Oleg
Published: May 2022

A new parallel code based on models of special relativistic hydrodynamics is presented for describing interacting flows. A new highly accurate numerical method is considered and verified. A parallel implementation of the method by means of Coarray Fortran technology and its efficiency are described in detail. The code scalability is 92% on a cluster with Intel Xeon 6248R NKS-1P with 192 Coarray Fortran images. Different interacting relativistic flows are considered as astrophysical applications.
Effect of Green Supply Chain Management Practices on Environmental Performance: Case of Mexican Manufacturing Companies
Authors: García Alcaraz Jorge Luis , Díaz Reza José Roberto , Arredondo Soto Karina Cecilia , Hernández Escobedo Guadalupe , Happonen Ari , Puig I Vidal Rita , Jiménez Macías Emilio
Published: May 2022

Managers implement several Green Supply Chain Management (GSCM) practices to improve sustainability and economic performance, such as environmental management systems (EMS), eco-design (ED), source reduction (SR) and attending to external environmental management (EEM) requirements; however, the relationship among them requires a deep study. This paper reports the case of the Mexican maquiladora industry, analyzing the main relationships among GSCM practices with environmental impact (EI) and environmental cost savings (ECS). The analysis reports three structural equation models (SEM) developed as simple, second-order, and mediating models. Those relationships are tested using 160 responses to a survey applied to the Mexican maquiladora industry and with partial least squares algorithms (PLS), where conditional probabilities for different scenarios in latent variables are also reported. Findings indicate that EMS has a direct effect on EI (β = 0.442) and ECS (β = 0.227), indicating that EMS reduces EI and cost associated with the production process; however, ED has no direct effect on EI (β = 0.019) and ECS ((β = 0.006), and it can be due to the maquiladora nature as foreign companies focused on manufacturing and not to product design.
Suitability of Marine- and Porcine-Derived Collagen Type I Hydrogels for Bioprinting and Tissue Engineering Scaffolds
Authors: Maher Malachy , Glattauer Veronica , Onofrillo Carmine , Duchi Serena , Yue Zhilian , Hughes Timothy C. , Ramshaw John A. M. , Wallace Gordon G.
Published: May 2022

Collagens from a wide array of animals have been explored for use in tissue engineering in an effort to replicate the native extracellular environment of the body. Marine-derived biomaterials offer promise over their conventional mammalian counterparts due to lower risk of disease transfer as well as being compatible with more religious and ethical groups within society. Here, collagen type I derived from a marine source (Macruronus novaezelandiae, Blue Grenadier) is compared with the more established porcine collagen type I and its potential in tissue engineering examined. Both collagens were methacrylated, to allow for UV crosslinking during extrusion 3D printing. The materials were shown to be highly cytocompatible with L929 fibroblasts. The mechanical properties of the marine-derived collagen were generally lower than those of the porcine-derived collagen; however, the Young’s modulus for both collagens was shown to be tunable over a wide range. The marine-derived collagen was seen to be a potential biomaterial in tissue engineering; however, this may be limited due to its lower thermal stability at which point it degrades to gelatin.
Co-Infection of Oral Candida albicans and Porphyromonas gingivalis Is Associated with Active Periodontitis in Middle-Aged and Older Japanese People
Authors: Oka Iori , Shigeishi Hideo , Ohta Kouji
Published: May 2022

Background and Objectives: Candida albicans can be detected in subgingival sites of patients with periodontitis. However, the association between oral Candida albicans and periodontitis has not been fully elucidated in Japanese adults. The aim of this study is to clarify the relationship between oral Candida albicans infection/co-infection of oral C. albicans and Porphyromonas gingivalis and periodontitis among middle-aged and older Japanese people. Materials and Methods: Eighty-six patients (mean age 70.4 years) who visited the Hiroshima University Hospital from April to September 2021 were investigated in this study. Oral swab samples were collected from the tongue surface. C. albicans and P. gingivalis DNA was detected by real-time PCR using specific DNA primer sets. C. albicans-positive participants were classified into two groups according to the presence or absence of intron insertion of C. albicans DNA by PCR analysis. Results: C. albicans was detected in 22 (25.6%) of the 86 patients. Patients in their 80s recorded a higher C. albicans-positive rate (35.3%) compared with other participants. However, there was no significant association between the C. albicans positivity rate and clinical parameters such as sex, age, systemic disease, denture use, or oral health status. Of the 22 C. albicans-positive participants, 10 participants (45.5%) had C. albicans with intron insertion; 70% of participants who had C. albicans with intron insertion exhibited ≥6 mm probing depth. C. albicans/P. gingivalis co-infection was found in 12 patients (14%). Importantly, binomial logistic regression analysis revealed that C. albicans/P. gingivalis co-infection was significantly associated with ≥6 mm periodontal pockets with bleeding on probing (p = 0.02). Conclusions: Co-infection of C. albicans and P. gingivalis is involved in active periodontitis in middle-aged and older people.
Change in Lung Fluid Volume during Exercise in Patients with Exercise-Induced Mitral Regurgitation
Authors: Imamura Teruhiko , Hori Masakazu , Tanaka Shuhei , Narang Nikhil , Kinugawa Koichiro
Published: May 2022

Exercise-induced mitral regurgitation (MR) can be diagnosed during stress echocardiography testing. Remote dielectric sensing (ReDSTM) is a noninvasive electromagnetic-based modality to measure lung fluid levels. The change in lung fluid levels in patients with MR during stress echocardiography remains unknown. Patients with symptomatic MR at baseline and suspected worsening exercise-induced MR underwent stress echocardiography. ReDS values were measured before and after the tests. A total of four patients (ages ranging between 74 and 84 years old, three women) underwent stress echocardiography testing using a bicycle ergometer. In patient A, MR effective regurgitant orifice area (EROA) remained unchanged and ReDS values decreased. EROA increased significantly with a small incremental change in ReDS values in patient B and patient C, who underwent valve repair with MitraClip later. Patient D had a mild increase in MR EROA but a considerable increase in ReDS values (from 22% to 32%), and eventually received valve repair with MitraClip. The ReDS system may be a complementary tool to conventional stress echocardiography in the evaluation of clinically significant MR and considering mitral valve intervention.
The Possible Effects of Zinc Supplementation on Postpartum Depression and Anemia
Authors: Aoki Chieko , Imai Kenji , Owaki Taro , Kobayashi-Nakano Tomoko , Ushida Takafumi , Iitani Yukako , Nakamura Noriyuki , Kajiyama Hiroaki , Kotani Tomomi
Published: May 2022

Background and Objectives: The effects of postpartum zinc supplementation are still unclear. Our purpose in this study is to investigate the association between Zn supplementation and postpartum depression, defined by an Edinburgh Postnatal Depression Scale (EPDS) score ≥ 9, and the effect on the hematological status of postpartum women. Materials and Methods: We first investigated whether zinc supplementation affected the perioperative levels of zinc, hemoglobin, and hematocrit in 197 cases who underwent cesarean section and had postpartum anemia. Next, logistic regression analyses were performed on 148 eligible cases to determine the association between zinc supplementation and postpartum depression. Results: Postpartum zinc supplementation significantly improved the status of maternal blood zinc levels and reduced the risk of developing postpartum depression (adjusted odds ratio: 0.249; 95% confidence interval: 0.062–0.988; p = 0.048). Iron supplementation is a standard and effective strategy for treating anemia; however, the combination of oral iron plus zinc supplementation resulted in slightly significant negative effects on postpartum hemoglobin and hematocrit compared to oral iron supplementation only. Conclusions: Postpartum zinc supplementation causes a significant positive effect on postpartum depression (EPDS score ≥ 9). Zinc supplementation had a negative but transient influence on the hematological status in women with postpartum anemia treated with oral iron supplementation; however, the differences were not clinically significant. Thus, we did not regard it as an adverse effect to be considered, and postpartum zinc supplementation may be viewed as beneficial in postpartum women.
Cervical Cancer Prevention in the Era of the COVID-19 Pandemic
Authors: Poniewierza Patryk , Panek Grzegorz
Published: May 2022

Background and Objectives: Cervical cancer (CC) is the fourth most common cause of cancer-related morbidity and mortality among women worldwide. CC prevention is based on screening and HPV vaccination. The COVID-19 pandemic has caused difficulties in implementing CC-preventative measures. The aim of this study was to collect data on the implementation of CC prophylaxis in Poland provided by public and private health care with a particular focus on the impact of the COVID-19 pandemic and attempt to estimate the level of CC-screening implementation by 2026 under public and private health care. Materials and Methods: Data on the implementation of privately funded (2016–2021) and publicly funded (2014–2021) CC-preventative measures in Poland were examined. The Prophet algorithm, which positions itself as an automatic forecasting procedure and represents a local Bayesian structural time-series model, was used to predict data. The correlation test statistic was based on Pearson’s product moment correlation coefficient and follows a t distribution. An asymptotic confidence interval was given based on Fisher’s Z transform. Results: In 2021, a significantly higher population screening coverage was observed in private health care (71.91%) than in the public system (12.6%). Our estimation assumes that the adverse downward trend of population coverage (pap smear CC screening) in the public system will continue to 5.02% and in the private health system to 67.92% in 2026. Correlation analysis showed that with the increase in the sum of HPV tests and LBC, the percentage of Pap smear coverage in the private healthcare sector decreases r = −0.62, p = 0.260 df = 3, CI = [−0.97, 0.57]. The amount of HPV vaccinations provided in private health care is steadily increasing. Immunization coverage of the population of girls aged 9–18 years under private health care at the end of the observation period was 4.3% (2021). Conclusions: It is necessary to reorganize the public CC-screening system in Poland based on a uniform reporting system for tests performed in both public and private health care using the model of action proposed by us. We recommend the introduction of a national free HPV vaccination program funded by the government and implemented in public and private health care facilities.
A Rare Case of Didanosine-Induced Mid-Peripheral Chorioretinal Atrophy Identified Incidentally 11 Years after the Drug Cessation
Authors: Joharjy Heba , Pisella Pierre-Jean , Audo Isabelle , Le-Lez Marie Laure
Published: May 2022

Objective: This article aims to describe a unique case of didanosine-induced retinal degeneration that was discovered 11 years after the drug withdrawal. Case report: The patient is a 42-year-old woman with a medical history of HIV and hepatitis C virus since 2004. She has been prescribed antiretroviral therapy since then. For the first seven years (2004–2011), the patient was prescribed a combination therapy consisting of didanosine, efavirenz, and lamivudine. The protocol was changed to atripla (efavirenz, emtricitabine, and tenofovir) from 2011 to 2021. Recently (October 2021–January 2021), the patient was prescribed eviplera (rilpivirin, emtricitabine, and tenofovir). In addition, her past medical history revealed Gougerot-Sjogren syndrome and rheumatoid arthritis. She was prescribed hydroxychloroquine (HCQ) (2009–2021) at a dose of 400 mg daily. She had no vision complaint. Results: During her routine HCQ screening at the eye clinic, University Hospital Bretonneau, Tours, France, the widefield colour fundus photograph showed well-defined symmetric mid-peripheral areas of chorioretinal atrophy sparing the posterior pole of both eyes. Furthermore, the widefield fundus autofluorescence illustrated mid-peripheral round well-demarcation hypoautofluorescent areas of chorioretinal atrophy of both eyes. Conversely, the macular optical coherence tomography (OCT) was normal. Many of her drugs are known to be associated with retinopathy such as HCQ, tenofovir, efavirenz, and didanosine. Because our data corroborate peripheral retinal damage rather than posterior pole damage, this case report is compatible with didanosine-induced retinopathy rather than HCQ, efavirenz, or tenofovir retinal toxicity. Conclusions: All HIV patients who are presently or were previously on didanosine therapy should have their fundus examined utilising widefield fundus autofluorescence and photography.
Adrenal Tumors in Young Adults: Case Reports and Literature Review
Authors: Zdrojewska Małgorzata , Mech-Siebieszuk Emilia , Świątkowska-Stodulska Renata , Regent Bartosz , Kunc Michał , Zdrojewski Łukasz , Sworczak Krzysztof
Published: May 2022

The current high detection rate of adrenal tumors (4–10% of general population) is attributable to a widespread use of variety of imaging studies, especially a computed tomography. Most of them represent clinically silent and biologically indolent incidentalomas, but some adrenal tumors may pose a significant clinical challenge. Thus, in every patient with an adrenal tumor, a decision on further management is made after careful hormonal and radiological evaluation. All hormonally active tumors and those with radiological features suggesting malignancy are qualified for surgery. Approximately 80% of adrenal tumors are adrenocortical adenomas, hypertrophy, or nodular adrenocortical hyperplasia. Other histopathological diagnoses include pheochromocytoma, adrenocortical carcinoma, metastases, mesenchymal tumors, lymphomas, cysts, and ganglioneuromas. Adrenal tumors are more commonly diagnosed and better studied in elderly patients. In younger patients, under 40 years old, focal adrenal lesions are relatively rare, and histological distribution of diagnoses differs from that in elderly individuals. Younger patients are more likely to display endocrine symptoms, which raise the suspicion of an adrenal mass. In the current study, we present a case series of seven adrenal tumors occurring in young patients. The cases presented below, along with the literature review, demonstrate that the diagnosis and treatment of adrenal tumors are crucial due to endocrinopathy-derived complications and a potential risk of malignancy.
Tailoring the Selective Permeation Properties of Asymmetric Cellulose Acetate/Silica Hybrid Membranes and Characterisation of Water Dynamics in Hydrated Membranes by Deuterium Nuclear Magnetic Resonance
Authors: da Silva Miguel P. , Beira Maria J. , Nogueira Isabel D. , Sebastião Pedro J. , Figueirinhas João L. , de Pinho Maria Norberta
Published: May 2022

In this work, the water order and dynamics in hydrated films of flat asymmetric cellulose acetate (CA)/silica, CA/SiO2, and hybrid membranes, covering a wide range of nanofiltration (NF) and ultrafiltration (UF) permeation properties, were characterised by deuterium nuclear magnetic resonance (DNMR) relaxation. The range of NF/UF characteristics was attained by subjecting three CA/SiO2 membranes, prepared from casting solutions with different acetone/formamide ratios to drying post-treatments of solvent exchange and conditioning with surfactant mixtures. Post-treated and pristine CA/SiO2 membranes were characterised in terms of hydraulic permeability, selective permeation properties and molecular weight cut-off. These results were correlated with the DNMR relaxation findings. It was found that the post-treatment by solvent exchange caused membrane shrinkage that led to very different permeation characteristics and a significant enhancement of the DNMR relaxation observables. In contrast, conditioning with surfactant solutions exhibited a weaker effect over those properties. Scanning electron microscopy (SEM) images were obtained for the membranes post-treated with solvent exchange to confirm their asymmetric nature. This work provides an essential indication that DNMR relaxometry is a reliable tool to characterise the asymmetric porous structures of the NF/UF CA/SiO2 hybrid membranes.
Engineered Approaches to Facile Identification of Tiny Microplastics in Polymeric and Ceramic Membrane Filtrations for Wastewater Treatment
Authors: Kook Heejin , Park Chanhyuk
Published: May 2022

Wastewater treatment plants (WWTPs) contribute to the release of significant quantities of microplastics into the aquatic environment. The facile identification of microplastics and an understanding of their occurrence and transport through WWTPs are essential for improving microplastic retention. Potential microplastic treatment technologies for both polymeric and ceramic membrane filtrations were systematically investigated to inform decisions on the optimal choice of membrane for effective microplastic retention. A blocking filtration model, based on a simple linear regression fitting, was used in experiments on the filtration of microplastic suspensions to determine the relative importance of individual fouling mechanisms. Unlike the commonly applied spectroscopic techniques, the facile identification approaches, that are closely related to the amounts of particles within wastewater samples, attempted to identify tiny microplastics (<1.0 μm) by comparing them against silica particles for reference. A larger decline in the normalized permeate flux was observed for 0.1 μm polystyrene microplastics, while standard pore blocking appeared to be the dominant fouling mechanism for all membranes. More microplastics based on turbidity and total solids were removed using the ceramic membrane than the other polymeric membranes. However, fewer microplastics, based on the particle size distribution analysis, were removed using the ceramic membrane as the pore size measurements gave a relatively large pore size for the ceramic membrane, compared with other polymeric membranes; even though a nominal pore size of 0.1 μm for all membranes were provided by the suppliers. The contribution of microplastic-containing synthetic wastewaters to overall flux decline was significantly greater than those of identical microplastic suspensions because of the aggregation of larger microplastics with dissolved organic matter in synthetic wastewater, leading to the formation of a cake layer on the membrane surface. Despite the challenges associated with the facile identification approaches, our findings provided deeper insights and understanding of how microplastics behave in membrane filtration, which could enable the application of potential microplastic treatment technologies.
Effects of Diatomite Contents on Microstructure, Microhardness, Bioactivity and Biocompatibility of Gradient Bioceramic Coating Prepared by Laser Cladding
Authors: Zhang Guofen , Liu Qibin
Published: May 2022

Biometallic materials are widely used in medicine because of excellent mechanical properties. However, biometallic materials are limited in the application of biomaterials due to their lack of bioactivity. To solve this problem, a gradient bioceramic coating doped with diatomite (DE) was successfully fabricated on the surface of Ti6Al4V alloy by using the broadband-laser cladding process to improve the bioactivity of metal materials. As well as the DE contents on the microstructure, microhardness, bioactivity and biocompatibility were investigated. The experimental results demonstrate that the addition of moderate amounts of DE is effective in reducing the number of cracks. The X-ray diffraction (XRD) results reveal that the bioceramic coating doped with DE mainly consists of CaTiO3, hydroxyapatite (HA), tricalcium phosphate (TCP) and silicate, and that the amount of HA and TCP in the coating reached maximum when the bioceramic coating was doped with 10wt% DE. The bioceramic coating doped with 10wt% DE has favorable ability to deposit bone-like apatite. These results indicate that the addition of DE can improve cracking sensibility, bioactivity and biocompatibility of the coating.
Production of Closed-Cell Foams Out of Aluminum Chip Waste: Mathematical Modeling and Optimization
Authors: Krolo Jure , Lela Branimir , Grgić Karla , Jozić Sonja
Published: May 2022

The main aim of this research is to mathematically describe the influence of the processing parameters of metal foam production from machining chip waste. Using this method, metal foams were produced without a remelting step, which should be both economically and environmentally effective. Firstly, expensive metal powders were replaced with waste in the form of machining chips. Secondly, machining chip waste was recycled without any significant material losses, which usually occurs during conventional recycling (using the melting process). To describe the innovative process and to relate metal foam properties to foaming temperature, the blowing agent weight percentage, and foam density (controlled by foaming height), response surface methodology, and the design of experiments were used. The quality of the produced metal foams was evaluated by determination of density, yield strength, compression strength, plateau stress, energy absorption, pore perimeter, and pore inhomogeneity for specimens obtained following the experimental plan. It was proven that pore inhomogeneity increased in the range from 1.41 to 4.81 mm with a higher temperature and the addition of a foaming agent. However, higher energy absorption and yield strength were obtained with a higher temperature but a lower percentage of TiH2. Despite the production from machining chips, pores were homogenous without significant cracks. These kinds of metal foams are comparable to commercial foams made of metal powders.
The Role of Parent Phase Topology in Double Young–Kurdjumow–Sachs Variant Selection during Phase Transformation in Low-Carbon Steels
Authors: Kestens Leo A. I. , Nguyen-Minh Tuan , Petrov Roumen H.
Published: May 2022

The present paper investigates the role of parent phase topology on a crystallographic variant selection rule. This rule assumes that product phase nuclei appear at certain grain boundaries in the parent structure, such that a specific crystallographic orientation relationship is observed with both parent grains at either side of the grain boundary. The specific crystallographic orientation correspondence considered here is the Young–Kurdjumow–Sachs (YKS) orientation relationship <112>90° (which exhibits 24 symmetrical equivalents). The aforementioned relationship is characteristic of phase transformations in low-carbon steel grades. It is shown that, for different parent phase textures, ~20% of the grain boundaries comply with the double YKS condition allowing for a tolerance of 5°, ignoring the presence of topology in the parent phase microstructure. The presented model allows for connecting the presence of a specific parent phase topology with the condition of the double YKS variant selection rule in a number of practical cases: (i) for hot rolled Ti–Interstitial Free (IF) steel with and without Mn addition, (ii) for cold rolled IF steel exhibiting very strong texture memory after forward and reverse α ⇌ γ phase transformation and (iii) for a martensitic transformation in a Fe–8.5% Cr steel. It is shown that the double YKS variant selection criterion may explain several specific features of the observed transformation textures, while assuming a non-correlated arbitrary pair topology of the parent austenite structure (implying that for N parent orientations N/2 pairs are selected in an arbitrary manner).
NMR-Based Metabolomics in Differential Diagnosis of Chronic Kidney Disease (CKD) Subtypes
Authors: Chasapi Styliani A. , Karagkouni Evdokia , Kalavrizioti Dimitra , Vamvakas Sotirios , Zompra Aikaterini , Takis Panteleimon G. , Goumenos Dimitrios S. , Spyroulias Georgios A.
Published: May 2022

Chronic Kidney Disease (CKD) is considered as a major public health problem as it can lead to end-stage kidney failure, which requires replacement therapy. A prompt and accurate diagnosis, along with the appropriate treatment, can delay CKD’s progression, significantly. Herein, we sought to determine whether CKD etiology can be reflected in urine metabolomics during its early stage. This is achieved through the analysis of the urine metabolic fingerprint from 108 CKD patients by means of Nuclear Magnetic Resonance (NMR) spectroscopy metabolomic analysis. We report the first NMR—metabolomics data regarding the three most common etiologies of CKD: Chronic Glomerulonephritis (IgA and Membranous Nephropathy), Diabetic Nephropathy (DN) and Hypertensive Nephrosclerosis (HN). Analysis aided a moderate glomerulonephritis clustering, providing characterization of the metabolic fluctuations between the CKD subtypes and control disease. The urine metabolome of IgA Nephropathy reveals a specific metabolism, reflecting its different etiology or origin and is useful for determining the origin of the disease. In contrast, urine metabolomes from DN and HN patients did not reveal any indicative metabolic pattern, which is consistent with their fused clinical phenotype. These findings may contribute to improving diagnostics and prognostic approaches for CKD, as well as improving our understanding of its pathology.
Cellular Aquaculture: Prospects and Challenges
Authors: Goswami Mukunda , Belathur Shambhugowda Yashwanth , Sathiyanarayanan Arjunan , Pinto Nevil , Duscher Alexandrea , Ovissipour Reza , Lakra Wazir Singh , Chandragiri Nagarajarao Ravishankar
Published: May 2022

Aquaculture plays an important role as one of the fastest-growing food-producing sectors in global food and nutritional security. Demand for animal protein in the form of fish has been increasing tremendously. Aquaculture faces many challenges to produce quality fish for the burgeoning world population. Cellular aquaculture can provide an alternative, climate-resilient food production system to produce quality fish. Potential applications of fish muscle cell lines in cellular aquaculture have raised the importance of developing and characterizing these cell lines. In vitro models, such as the mouse C2C12 cell line, have been extremely useful for expanding knowledge about molecular mechanisms of muscle growth and differentiation in mammals. Such studies are in an infancy stage in teleost due to the unavailability of equivalent permanent muscle cell lines, except a few fish muscle cell lines that have not yet been used for cellular aquaculture. The Prospect of cell-based aquaculture relies on the development of appropriate muscle cells, optimization of cell conditions, and mass production of cells in bioreactors. Hence, it is required to develop and characterize fish muscle cell lines along with their cryopreservation in cell line repositories and production of ideal mass cells in suitably designed bioreactors to overcome current cellular aquaculture challenges.
Design of the Threshold-Controllable Memristor Emulator Based on NDR Characteristics
Authors: Lin Mi , Luo Wenyao , Li Luping , Han Qi , Lyu Weifeng
Published: May 2022

Due to the high manufacturing cost of memristors, an equivalent emulator has been employed as one of the mainstream approaches of memristor research. A threshold-type memristor emulator based on negative differential resistance (NDR) characteristics is proposed, with the core part being the R-HBT network composed of transistors. The advantage of the NDR-based memristor emulator is the controllable threshold, where the state of the memristor can be changed by setting the control voltage, which makes the memristor circuit design more flexible. The operation frequency of the memristor emulator is about 250 kHz. The experimental results prove the feasibility and correctness of the threshold-controllable memristor emulator circuit.
Surface Hydrophilic Modification for Chip of Centrifugal Microfluidic Immunoassay System
Authors: Shi Yuxing , Ye Peng , Wang Chuang , Yang Kuojun , Guo Jinhong
Published: May 2022

The surface of a centrifugal microfluidic immunoassay system chip such as polymethyl methacrylate (PMMA) is often hydrophobic, which leads to problems such as poor liquid transfer efficiency and easy-to-block siphon channels, leading to bad fluid control. Therefore, surface hydrophilic modification for such chips is necessary to improve the rapidity and sensitivity of the system. Chemical modification is commonly used, but there is little research on the hydrophilic effect of different concentrations of hydrophilic reagents. According to function requirements for different microchannels of the chip (some only need to ensure the liquid can flow into the next chamber, and some also need to ensure the function of “closing the door” during immunoassay incubation), we explored the best combination of hydrophilic reagent and concentration through experiments. Firstly, three hydrophilic reagents were used for modification. Secondly, the hydrophilic effects of different reagents and concentrations were explored by contact angle test, the influence of different modification methods on liquid transfer efficiency was characterized by residual liquid calculation in the chamber. Finally, the effect of different hydrophilic reagents on absorbance was also tested. By experimental results and comprehensively considering the stability of the modification effect and the function requirements, Tween-20 (2.0% v/v) was chosen as the modifying reagents of the first siphon valve and the second siphon valve, and TritonX-100 (2.0% v/v) was chosen for the third siphon valve, which effectively reduces the contact angle and improves the liquid transfer efficiency, leading to further improvement of the rapidity and sensitivity of the centrifugal microfluidic immunoassay system by efficient siphoning and high plasma separation efficiency (99%).
Autonomous Exercise Generator for Upper Extremity Rehabilitation: A Fuzzy-Logic-Based Approach
Authors: Siddique Tanjulee , Fareh Raouf , Abdallah Mahmoud , Ahmed Zaina , Rahman Mohammad Habibur
Published: May 2022

In this paper, an autonomous exercise generation system based of fuzzy logic approach is presented. This work attempts to close a gap in the design of a completely autonomous robotic rehabilitation system that can recommend exercises to patients based on their data, such as shoulder range of motion (ROM) and muscle strength, from a pre-set library of exercises. The input parameters are fed into a system that uses Mamdani-style fuzzy logic rules to process them. In medical applications, the rationale behind decision making is a sophisticated process that involves a certain amount of uncertainty and ambiguity. In this instance, a fuzzy-logic-based system emerges as a viable option for dealing with the uncertainty. The system’s rules have been reviewed by a therapist to ensure that it adheres to the relevant healthcare standards. Moreover, the system has been tested with a series of test data and the results obtained ensures the proposed idea’s feasibility.
Concurrent Topological Structure and Cross-Infill Angle Optimization for Material Extrusion Polymer Additive Manufacturing with Microstructure Modeling
Authors: Tang Ruixiao , Zhang Chenghu , Liu Jikai
Published: May 2022

This paper contributes a concurrent topological structure and cross-infill angle optimization method for material extrusion type additive manufacturing (AM). This method features in modeling the process-induced material anisotropy through microscopic geometric modeling obtained by scanning electron micrographs. Numerical homogenization is performed to evaluate the equivalent effective properties of the 100-percentage cross-infilled local microstructures, and by introducing fitting functions, the relationship between equivalent effective material properties and varying cross-infill angles is empirically constructed. Then, optimization problems involving cross-infill angles as design variables are formulated, including concurrent optimization formulation. Numerical and experimental studies are conducted to illustrate the effectiveness of the proposed method. Both the numerical and experimental results demonstrate that the structural stiffness obtained by our proposed method has evidently improved.
Interaction between Electromechanical Fields and Carriers in a Multilayered Piezoelectric Semiconductor Beam
Authors: Hong Renzhong , Yang Wanli , Wang Yunbo
Published: May 2022

This study discusses the interaction between electromechanical fields and carriers in a multilayered ZnO beam where the c-axis of every two adjacent layers is alternately opposite along the thickness direction. A multi-field coupling model is proposed from the Timoshenko beam theory together with the phenomenological theory of piezoelectric semiconductors, including Gauss’s law and the continuity equation of currents. The analytical solutions are obtained for a bent beam with different numbers of layers. Numerical results show that polarized charges occur at the interfaces between every two adjacent layers due to the opposite electromechanical coupling effects. It was found that a series of alternating potential-barrier/well structures are induced by the polarized charges, which can be used to forbid the passing of low-energy mobile charges. Moreover, it was also observed that the induced polarized charges could weaken the shielding effect of carrier redistribution. These results are useful for the design of piezotronic devices.
Serological Hendra Virus Diagnostics Using an Indirect ELISA-Based DIVA Approach with Recombinant Hendra G and N Proteins
Authors: Balkema-Buschmann Anne , Fischer Kerstin , McNabb Leanne , Diederich Sandra , Singanallur Nagendrakumar Balasubramanian , Ziegler Ute , Keil Günther M. , Kirkland Peter D. , Penning Maren , Sadeghi Balal , Marsh Glenn , Barr Jennifer , Colling Axel
Published: May 2022

Since the identification of Hendra virus (HeV) infections in horses in Australia in 1994, more than 80 outbreaks in horses have been reported, and four out of seven spillover infections in humans had a fatal outcome. With the availability of a subunit vaccine based on the HeV-Glycoprotein (HeV-G), there is a need to serologically Differentiate the Infected from the Vaccinated Animals (DIVA). We developed an indirect ELISA using HeV-G expressed in Leishmania tarentolae and HeV-Nucleoprotein (HeV-N) expressed in recombinant baculovirus-infected insect cells as antigens. During evaluation, we tested panels of sera from naïve, vaccinated and infected horses that either originated from a Hendra-virus free region, or had been pre-tested in validated diagnostic tests. Our data confirm the reliability of this approach, as HeV-N-specific antibodies were only detected in sera from infected horses, while HeV-G-specific antibodies were detected in infected and vaccinated horses with a high level of specificity and sensitivity. Given the excellent correlation of data obtained for German and Australian HeV-negative horses, we assume that this test can be applied for the testing of horse serum samples from a variety of geographical regions.
Fungal Diversity in Two Wastewater Treatment Plants in North Italy
Authors: Buratti Simone , Girometta Carolina Elena , Baiguera Rebecca Michela , Barucco Barbara , Bernardi Marco , De Girolamo Giuseppe , Malgaretti Maura , Oliva Desdemona , Picco Anna Maria , Savino Elena
Published: May 2022

In urban wastewater treatment plants, bacteria lead the biological component of the depuration process, but the microbial community is also rich in fungi (mainly molds, yeasts and pseudo-yeasts), whose taxonomical diversity and relative frequency depend on several factors, e.g., quality of wastewater input, climate, seasonality, and depuration stage. By joining morphological and molecular identification, we investigated the fungal diversity in two different plants for the urban wastewater treatment in the suburbs of the two major cities in Lombardia, the core of industrial and commercial activities in Italy. This study presents a comparison of the fungal diversity across the depuration stages by applying the concepts of α-, β- and ζ-diversity. Eurotiales (mainly with Aspergillus and Penicillium), Trichosporonales (Trichosporon sensu lato), Saccharomycetales (mainly with Geotrichum) and Hypocreales (mainly with Fusarium and Trichoderma) are the most represented fungal orders and genera in all the stages and both the plants. The two plants show different trends in α-, β- and ζ-diversity, despite the fact that they all share a crash during the secondary sedimentation and turnover across the depuration stages. This study provides an insight on which taxa potentially contribute to each depuration stage and/or keep viable propagules in sludges after the collection from the external environment.
Whole Genome Characterization of the High-Risk Clone ST383 Klebsiella pneumoniae with a Simultaneous Carriage of blaCTX-M-14 on IncL/M Plasmid and blaCTX-M-15 on Convergent IncHI1B/IncFIB Plasmid from Egypt
Authors: Edward Eva A. , Mohamed Nelly M. , Zakaria Azza S.
Published: May 2022

Recently, Egypt has witnessed the emergence of multidrug-resistant (MDR) Klebsiella pneumoniae, which has posed a serious healthcare challenge. The accelerated dissemination of blaCTX-M genes among these MDR K. pneumoniae, particularly blaCTX-M-14 and blaCTX-M-15, have been noted. In this study, we investigated the occurrence of blaCTX-M-IV among K. pneumoniae recovered from the laboratory of a major hospital in Alexandria. The 23 tested isolates showed an MDR phenotype and the blaCTX-M-IV gene was detected in ≈22% of the isolates. The transformation of plasmids harboring blaCTX-M-IV to chemically competent cells of Escherichia coli DH5α was successful in three out of five of the tested blaCTX-M-IV-positive isolates. Whole genome sequencing of K22 indicated that the isolate belonged to the high-risk clone ST383, showing a simultaneous carriage of blaCTX-M-14 on IncL/M plasmid, i.e., pEGY22_CTX-M-14, and blaCTX-M-15 on a hybrid IncHI1B/IncFIB plasmid, pEGY22_CTX-M-15. Alignment of both plasmids revealed high similarity with those originating in the UK, Germany, Australia, Russia, China, Saudi Arabia, and Morocco. pEGY22_CTX-M-15 was a mosaic plasmid that demonstrated convergence of MDR and virulence genes. The emergence of such a plasmid with enhanced genetic plasticity constitutes the perfect path for the evolution of K. pneumoniae isolates causing invasive untreatable infections especially in a country with a high burden of infectious diseases such as Egypt. Therefore there is an imperative need for countrywide surveillances to monitor the prevalence of these superbugs with limited therapeutic options.
Antimicrobial Effects of L-Chg10-Teixobactin against Enterococcus faecalis In Vitro
Authors: Jarkhi Alaa , Lee Angeline Hui Cheng , Sun Zhenquan , Hu Mingxin , Neelakantan Prasanna , Li Xuechen , Zhang Chengfei
Published: May 2022

Objective: Teixobactin and its analogues are a new class of antibiotics that have no detectable bacterial resistance. This study was designed to determine the antibacterial and antibiofilm activities of a novel teixobactin analogue, L-Chg10-teixobactin, against two strains of Enterococcus faecalis (E. faecalis). Materials and Methods: The efficacy of L-Chg10-teixobactin against two strains of E. faecalis (ATCC 29212 and 47077) was determined using Clinical and Laboratory Standards Institute methods. L-Chg10-teixobactin was prepared at a stock concentration of 1 mg/mL in 5% DMSO. The minimum inhibitory concentration (MIC) was calculated using a two-fold serial broth dilution method, utilizing a 96-well plate. The minimum bactericidal concentration (MBC) was determined by plating the bacteria onto agar to define the concentration that resulted in 99.9% of bacterial death. Ampicillin was used as the control. The effect of L-Chg10-teixobactin on the inhibition of ATCC 47077 strain biofilm formation was determined by measuring the minimum biofilm inhibitory concentration (MBIC) using the safranin assay, while the eradication of the preformed biofilm was determined by measuring the minimum biofilm eradication concentration (MBEC) using the XTT assay. For nonlinear data, the log dose–response curve was plotted to calculate the optimum concentration using Excel (version 16.51, Microsoft® excel. 2021, Microsoft Corporation, Reymond, WA, USA). The data are presented as mean ± standard deviation (SD). Results: The MIC and MBC values of L-Chg10-teixobactin against both strains of E. faecalis were 0.8 μg/mL. The MIC of ampicillin was 1.25 μg/mL for ATCC 29212 and ranged from 1.25 to 5 μg/mL for ATCC 47077. The MBC of ampicillin for ATCC 29212 and ATCC 47077 was 10 and 20 μg/mL, respectively. The MIC and MBC of ampicillin were much higher compared with those of L-Chg10-teixobactin. The MBEC80 of L-Chg10-teixobactin was 4.60 μg/mL for ATCC 47077, which was much lower than that of ampicillin (20 μg/mL). Conclusions:L-Chg10-teixobactin demonstrated potent antibacterial and antibiofilm effects against E. faecalis, suggesting its potential role an effective antibacterial and antibiofilm agent in endodontic treatment.
Lineage Replacement Associated with Fitness Gain in Mammalian Cells and Aedes aegypti: A Catalyst for Dengue Virus Type 2 Transmission
Authors: Tan Cheong Huat , Hapuarachchi Hapuarachchige Chanditha , Tan Li Kiang , Wong Pei Sze Jeslyn , Li Mei Zhi Irene , Wong Wing Yan , Ng Lee Ching
Published: May 2022

Shifting of virus serotypes and clade replacement events are known to drive dengue epidemics. However, only a few studies have attempted to elucidate the virus attributes that contribute to such epidemics. In 2007, Singapore experienced a dengue outbreak affecting more than 8000 individuals. The outbreak ensued with the shuffling of dominant clades (from clade I to clade II) of Dengue virus 2 (DENV-2) cosmopolitan genotype, at a time when the Aedes premise index was significantly low. Therefore, we hypothesized that clade II had higher epidemic potential and fitness than clade I. To test this hypothesis, we tested the replication and apoptotic qualities of clade I and II isolates in mammalian cells and their ability to infect and disseminate in a field strain of Ae. Aegypti. Our findings indicated that clade II replicated more efficiently in mammalian cells than clade I and possessed higher transmission potential in local vectors. This could collectively improve the epidemic potential of clade II, which dominated during the outbreak in 2007. The findings exemplify complex interactions between the emergence, adaptation and transmission potential of DENV, and testify the epidemiological importance of a deeper understanding of virus and vector dynamics in endemic regions.
Cellular Modifications of Rhodococci Exposed to Separate and Combined Effects of Pharmaceutical Pollutants
Authors: Ivshina Irina , Bazhutin Grigory , Tyan Semyon , Polygalov Maxim , Subbotina Maria , Tyumina Elena
Published: May 2022

Actinomycetes of the genus Rhodococcus (class Actinomycetia) are dominant dwellers of biotopes with anthropogenic load. They serve as a natural system of primary response to xenobiotics in open ecosystems, initiate defensive responses in the presence of pollutants, and are regarded as ideal agents capable of transforming and degrading pharmaceuticals. Here, the ability of selected Rhodococcus strains to co-metabolize nonsteroidal anti-inflammatory drugs (ibuprofen, meloxicam, and naproxen) and information on the protective mechanisms of rhodococci against toxic effects of pharmaceuticals, individually or in a mixture, have been demonstrated. For the first time, R. ruber IEGM 439 provided complete decomposition of 100 mg/L meloxicam after seven days. It was shown that versatile cellular modifications occurring at the early development stages of nonspecific reactions of Rhodococcus spp. in response to separate and combined effects of the tested pharmaceuticals included changes in electrokinetic characteristics and catalase activity; transition from unicellular to multicellular life forms accompanied by pronounced morphological abnormalities; changes in the average size of vegetative cells and surface area-to-volume ratio; and the formation of linked cell assemblages. The obtained data are considered as adaptation mechanisms in rhodococci, and consequently their increased resistance to separate and combined effects of ibuprofen, meloxicam, and naproxen.
Assessment of Psyllid Handling and DNA Extraction Methods in the Detection of ‘Candidatus Liberibacter Solanacearum’ by qPCR
Authors: Quintana María , de-León Leandro , Cubero Jaime , Siverio Felipe
Published: May 2022

‘Candidatus Liberibacter solanacearum’ (CaLsol) is an uncultured bacterium, transmitted by psyllids and associated with several diseases in Solanaceae and Apiaceae crops. CaLsol detection in psyllids often requires insect destruction, preventing a subsequent morphological identification. In this work, we have assessed the influence on the detection of CaLsol by PCR in Bactericera trigonica (Hemiptera: Psyllidae), of four specimen preparations (entire body, ground, cut-off head, and punctured abdomen) and seven DNA extraction methods (PBS suspension, squashing on membrane, CTAB, Chelex, TRIsureTM, HotSHOT, and DNeasy®). DNA yield and purity ratios, time consumption, cost, and residues generated were also evaluated. Optimum results were obtained through grinding, but it is suggested that destructive procedures are not essential in order to detect CaLsol. Although CaLsol was detected by qPCR with DNA obtained by the different procedures, HotSHOT was the most sensitive method. In terms of time consumption and cost, squashed on membrane, HotSHOT, and PBS were the fastest, while HotSHOT and PBS were the cheapest. In summary, HotSHOT was accurate, fast, simple, and sufficiently sensitive to detect this bacterium within the vector. Additionally, cross-contamination with CaLsol was assessed in the ethanol solutions where B. trigonica specimens were usually collected and preserved. CaLsol-free psyllids were CaLsol-positive after incubation with CaLsol-positive specimens. This work provides a valuable guide when choosing a method to detect CaLsol in vectors according to the purpose of the study.