bluuebunny/crossref_metadata_2025 huggingface dataset:
A Review: Inductively Coupled Plasma Reactive Ion Etching of Silicon Carbide
Authors: Racka-Szmidt Katarzyna , Stonio Bartłomiej , Żelazko Jarosław , Filipiak Maciej , Sochacki Mariusz
Published: December 2021

The inductively coupled plasma reactive ion etching (ICP-RIE) is a selective dry etching method used in fabrication technology of various semiconductor devices. The etching is used to form non-planar microstructures—trenches or mesa structures, and tilted sidewalls with a controlled angle. The ICP-RIE method combining a high finishing accuracy and reproducibility is excellent for etching hard materials, such as SiC, GaN or diamond. The paper presents a review of silicon carbide etching—principles of the ICP-RIE method, the results of SiC etching and undesired phenomena of the ICP-RIE process are presented. The article includes SEM photos and experimental results obtained from different ICP-RIE processes. The influence of O2 addition to the SF6 plasma as well as the change of both RIE and ICP power on the etching rate of the Cr mask used in processes and on the selectivity of SiC/Cr etching are reported for the first time. SiC is an attractive semiconductor with many excellent properties, that can bring huge potential benefits thorough advances in submicron semiconductor processing technology. Recently, there has been an interest in SiC due to its potential wide application in power electronics, in particular in automotive, renewable energy and rail transport.
Simple Method for Apples’ Bruise Area Prediction
Authors: Słupska Monika , Syguła Ewa , Komarnicki Piotr , Szulczewski Wiesław , Stopa Roman
Published: December 2021

From the producers’ point of view, there is no universal and quick method to predict bruise area when dropping an apple from a certain height onto a certain type of substrate. In this study the authors presented a very simple method to estimate bruise volume based on drop height and substrate material. Three varieties of apples were selected for the study: Idared, Golden Delicious, and Jonagold. Their weight, turgor, moisture, and sugar content were measured to determine morphological differences. In the next step, fruit bruise volumes were determined after a free fall test from a height of 10 to 150 mm in 10 mm increments. Based on the results of the research, linear regression models were performed to predict bruise volume on the basis of the drop height and type of substrate on which the fruit was dropped. Wood and concrete represented the stiffest substrates and it was expected that wood would respond more subtly during the free fall test. Meanwhile, wood appeared to react almost identically to concrete. Corrugated cardboard minimized bruising at the lowest discharge heights, but as the drop height increased, the cardboard degraded and the apple bruising level reached the results as for wood and concrete. Contrary to cardboard, the foam protected apples from bruising up to a drop height of 50 mm and absorbed kinetic energy up to the highest drop heights. Idared proved to be the most resistant to damage, while Golden Delicious was medium and Jonagold was least resistant to damage. Numerical models are a practical tool to quickly estimate bruise volume with an accuracy of about 75% for collective models (including all cultivars dropped on each of the given substrate) and 93% for separate models (including single cultivar dropped on each of the given substrate).
Layered Oxygen-Deficient Double Perovskites as Promising Cathode Materials for Solid Oxide Fuel Cells
Authors: Klyndyuk Andrei I. , Chizhova Ekaterina A. , Kharytonau Dzmitry S. , Medvedev Dmitry A.
Published: December 2021

Development of new functional materials with improved characteristics for solid oxide fuel cells (SOFCs) and solid oxide electrolysis cells (SOECs) is one of the most important tasks of modern materials science. High electrocatalytic activity in oxygen reduction reactions (ORR), chemical and thermomechanical compatibility with solid electrolytes, as well as stability at elevated temperatures are the most important requirements for cathode materials utilized in SOFCs. Layered oxygen-deficient double perovskites possess the complex of the above-mentioned properties, being one of the most promising cathode materials operating at intermediate temperatures. The present review summarizes the data available in the literature concerning crystal structure, thermal, electrotransport-related, and other functional properties (including electrochemical performance in ORR) of these materials. The main emphasis is placed on the state-of-art approaches to improving the functional characteristics of these complex oxides.
Analysis of Tensile Strength and Failure Mechanism Based on Parallel Homogenization Model for Recycled Concrete
Authors: Peng Yijiang , Zakaria Semaoui , Sun Yucheng , Chen Ying , Zhang Lijuan
Published: December 2021

In this paper, a parallel homogenization model for recycled concrete was proposed. A new type of finite element method, the base force element method, based on the complementary energy principle and the parallel homogenization model, is used to conduct meso-level damage research on recycled concrete. The stress–strain softening curve and failure mechanism of the recycled concrete under uniaxial tensile load are analyzed using the nonlinear damage analysis program of the base force element method based on the parallel homogenization model. The tensile strength and destructive mechanisms of recycled concrete materials are studied using this parallel homogenization model. The calculation results are compared with the results of the experiments and meso-level random aggregate model analysis methods. The research results show that this parallel homogenization analysis method can be used to analyze the nonlinear damage analysis of recycled concrete materials. The tensile strength, stress–strain softening curve, and crack propagation process of recycled concrete materials can be obtained using the present method.
Confinement Effect and Efficiency of Concentrically Loaded RACFCST Stub Columns
Authors: Wang En , Liu Yicen , Lyu Fei , Ding Faxing , Xu Yunlong
Published: December 2021

Recycled aggregate concrete-filled steel tubular (RACFST) columns are widely recognized as efficient structural members that can reduce the environmental impact of the building industry and improve the mechanical behavior of recycled aggregate concrete (RAC). The objective of this study is to investigate the behavior of recycled aggregate concrete-filled circular steel tubular (RACFCST) stub columns subjected to the axial loading. Three-dimensional finite element (FE) models were established using a triaxial plastic-damage constitutive model of RAC considering the replacement ratio of recycled aggregates. The FE analytical results revealed that the decreased ultimate bearing capacity of RACFCST stub columns compared with conventional concrete infilled steel tubular (CFST) columns was mainly due to the weakened confinement effect and efficiency. This trend will become more apparent with the larger replacement ratio of recycled aggregates. A practical design formula of the ultimate bearing capacity of RACFCST stub columns subjected to axial load was proposed on the basis of the reasonably simplified cross-sectional stress nephogram at the ultimate state. The derivation process incorporated the equilibrium condition and the superposition theory. The proposed equation was evaluated by comparing its accuracy and accessibility to some well-known design formulae proposed by other researchers and some widely used design codes.
Study of the Impact of Graphite Orientation and Ion Transport on EDLC Performance
Authors: de St Aurin Joseph M. Gallet , Phillips Jonathan
Published: December 2021

A model study of electric double layer capacitor (EDLC)-style capacitors in which the electrodes were composed of low surface area-oriented flakes of graphite that compressed to form a paper-like morphology has suggested that ion transport rates significantly impact EDLC energy and power density. Twelve capacitors were constructed, each using the same model electrode material and the same aqueous NaCl electrolyte, but differing in relative electrode orientation, degree of electrode compression, and presence/absence of an ionic transport salt bridge. All were tested with a galvanostat over a range of discharge currents. Significant differences in energy and power density and estimated series resistance were found as a function of all the factors listed, indicating that capacitor performance is not simply a function of the electrode surface area. This simple postulation was advanced and tested against data: net ion (Na+, Cl−) ‘velocity’ during both charge and discharge significantly impacts capacitive performance.
Effective Optimisation of the Patient Circuits of an Oncology Day Hospital: Mathematical Programming Models and Case Study
Authors: González-Maestro Adrián , Brozos-Vázquez Elena , Casas-Méndez Balbina , López-López Rafael , López-Rodríguez Rosa , Reyes-Santias Francisco
Published: December 2021

In this paper, we first use the information we have on the patients of an oncology day hospital to distribute the treatment schedules they have in each of the visits to this centre. To do this, we propose a deterministic mathematical programming model in such a way that we minimise the duration of the waiting room stays of the total set of patients and taking into account the restrictions of the circuit. Secondly, we will look for a solution to the same problem under a stochastic approach. This model will explicitly consider the existing uncertainty in terms of the different times involved in the circuit, and this model also allows the reorganisation of the schedules of medical appointments with oncologists. The models are complemented by a tool that solves the problem of assigning nurses to patients. The work is motivated by the particular characteristics of a real hospital and the models are used and compared with data from this case.
Some Results on the q-Calculus and Fractional q-Differential Equations
Authors: Sheng Ying , Zhang Tie
Published: December 2021

In this paper, we first discuss some important properties of fractional q-calculus. Then, based on these properties and the q-Laplace transform, we translate a class of fractional q-differential equations into the equivalent q-differential equations with integer order. Thus, we propose a method for solving some linear fractional q-differential equations by means of solving the corresponding integer order equations. Several examples are provided to illustrate our solution method.
Questioning Our Credibility: An Exploration of the Professional Identity Development of Mathematics Teacher Educators
Authors: Cross Francis Dionne , Kaur Bharaj Pavneet , Liu Jinqing , Phillips Andrea , Park Rogers Meredith , Zhong Qiu , Cesljarev Claire , Lloyd Kemol
Published: December 2021

Preparing future mathematics teacher educators (MTEs) with knowledge that are needed to effectively support pre-service teachers (PSTs) is very important. However, little attention was paid to MTEs’ knowledge development, which is multifaceted and complex. This study investigates successes, challenges, and tensions that four international graduate MTEs and one mathematics teacher educator (TE) experienced in developing their identity as math teacher educators. In total, 20 h of interactive interviews were analyzed by using qualitative methods. Emerging themes include how MTEs establish a sense of credibility and how they feel they are navigating multiple identities. Among the graduate MTEs, credibility was described as having the following: (a) knowledge of and experience teaching in the US education system; (b) experience in teaching using a problem-solving approach; (c) the ability to enact theory in practice. While navigating multiple identities, graduate MTEs recognize their ethnic identities are central and influence their perceptions of self as MTEs, and how they think they are perceived by others. The results highlight the importance of understanding MTEs tensions and challenges and provide “in-the-moment” support along the journey of becoming teacher educators.
Design of ℓ1 New Suboptimal Fractional Delays Controller for Discrete Non-Minimum Phase System under Unknown-but-Bounded Disturbance
Authors: Ivanov Dmitrii , Granichin Oleg , Pankov Vikentii , Volkovich Zeev
Published: December 2021

ℓ1-regularization methodologies have appeared recently in many pattern recognition and image processing tasks frequently connected to ℓ1-optimization in the control theory. We consider the problem of optimal stabilizing controller synthesis for a discrete non-minimum phase dynamic plant described by a linear difference equation with an additive unknown-but-bounded noise. Under considering the “worst” case of noise, the solving of these optimization problem has a combinatorial complexity. The choosing of an appropriate sufficiently high sampling rate allows to achieve an arbitrarily small level of suboptimality using a noncombinatorial algorithm. In this paper, we suggest to use fractional delays to achieve a small level of suboptimality without increasing the sampling rate so much. We propose an approximation of the fractional lag with a combination of rounding and a first-order fractional lag filter. The suggested approximation of the fractional delay is illustrated via a simulation example with a non-minimum phase second-order plant. The proposed methodology appears to be suitable to be used in various pattern recognition approaches.
Power Muirhead Mean Operators for Interval-Valued Linear Diophantine Fuzzy Sets and Their Application in Decision-Making Strategies
Authors: Mahmood Tahir , Haleemzai Izatmand , Ali Zeeshan , Pamucar Dragan , Marinkovic Dragan
Published: December 2021

It is quite beneficial for every company to have a strong decision-making technique at their disposal. Experts and managers involved in decision-making strategies would particularly benefit from such a technique in order to have a crucial impact on the strategy of their company. This paper considers the interval-valued linear Diophantine fuzzy (IV-LDF) sets and uses their algebraic laws. Furthermore, by using the Muirhead mean (MM) operator and IV-LDF data, the IV-LDF power MM (IV-LDFPMM) and the IV-LDF weighted power MM (IV-LDFWPMM) operators are developed, and some special properties and results demonstrated. The decision-making technique relies on objective data that can be observed. Based on the multi-attribute decision-making (MADM) technique, which is the beneficial part of the decision-making strategy, examples are given to illustrate the development. To demonstrate the advantages of the developed tools, a comparative analysis and geometrical interpretations are also provided.
School Timetabling Optimisation Using Artificial Bee Colony Algorithm Based on a Virtual Searching Space Method
Authors: Zhu Kaixiang , Li Lily D. , Li Michael
Published: December 2021

Although educational timetabling problems have been studied for decades, one instance of this, the school timetabling problem (STP), has not developed as quickly as examination timetabling and course timetabling problems due to its diversity and complexity. In addition, most STP research has only focused on the educators’ availabilities when studying the educator aspect, and the educators’ preferences and expertise have not been taken into consideration. To fill in this gap, this paper proposes a conceptual model for the school timetabling problem considering educators’ availabilities, preferences and expertise as a whole. Based on a common real-world school timetabling scenario, the artificial bee colony (ABC) algorithm is adapted to this study, as research shows its applicability in solving examination and course timetabling problems. A virtual search space for dealing with the large search space is introduced to the proposed model. The proposed approach is simulated with a large, randomly generated dataset. The experimental results demonstrate that the proposed approach is able to solve the STP and handle a large dataset in an ordinary computing hardware environment, which significantly reduces computational costs. Compared to the traditional constraint programming method, the proposed approach is more effective and can provide more satisfactory solutions by considering educators’ availabilities, preferences, and expertise levels.
The Difficult-to-Treat del 17 p Patient—A Case Report in Chronic Lymphocytic Leukemia
Authors: Moldovianu Ana-Maria , Crisan Ana Manuela , Varady Zsofia , Coriu Daniel
Published: December 2021

Chronic lymphocytic leukemia (CLL) treatment strategies have evolved to include mechanism-driven drugs but now raise new questions regarding their optimum timing and sequencing. In high-risk patients, switching from pathway inhibitors to allogeneic stem cell transplantation (allo-HCT) is still a matter of intense debate. We report the case of a CLL patient with 17 p deletion treated with ibrutinib as a bridge to allo-HCT. Early relapse after allo-HCT urged the initiation of salvage therapy, including donor lymphocytes infusions, ibrutinib, and venetoclax. We aim to outline and discuss the potential benefits of novel therapies, the current role of allo-HCT in CLL, drug timing and sequencing, and the unmet need to improve the long-term outcome of high-risk CLL patients.
In-Situ H2O2 Cleaning for Fouling Control of Manganese-Doped Ceramic Membrane through Confined Catalytic Oxidation Inside Membrane
Authors: Tang Shengyin , Fu Wanyi , Song Tiantian , Tang Tianhao , Chen Li , Guo Jianning , Hermanowicz Slav W. , Zhang Xihui
Published: December 2021

This work presents an effective approach for manganese-doped Al2O3 ceramic membrane (Mn-doped membrane) fouling control by in-situ confined H2O2 cleaning in wastewater treatment. An Mn-doped membrane with 0.7 atomic percent Mn doping in the membrane layer was used in a membrane bioreactor with the aim to improve the catalytic activity toward oxidation of foulants by H2O2. Backwashing with 1 mM H2O2 solution at a flux of 120 L/m2/h (LMH) for 1 min was determined to be the optimal mode for in-situ H2O2 cleaning, with confined H2O2 decomposition inside the membrane. The Mn-doped membrane with in-situ H2O2 cleaning demonstrated much better fouling mitigation efficiency than a pristine Al2O3 ceramic membrane (pristine membrane). With in-situ H2O2 cleaning, the transmembrane pressure increase (ΔTMP) of the Mn-doped membrane was 22.2 kPa after 24-h filtration, which was 40.5% lower than that of the pristine membrane (37.3 kPa). The enhanced fouling mitigation was attributed to Mn doping, in the Mn-doped membrane layer, that improved the membrane surface properties and confined the catalytic oxidation of foulants by H2O2 inside the membrane. Mn3+/Mn4+ redox couples in the Mn-doped membrane catalyzed H2O2 decomposition continuously to generate reactive oxygen species (ROS) (i.e., HO• and O21), which were likely to be confined in membrane pores and efficiently degraded organic foulants.
Biodegradable and Reusable Cellulose-Based Nanofiber Membrane Preparation for Mask Filter by Electrospinning
Authors: Wang Jizhen , Liu Shaoyang , Yan Xu , Jiang Zhan , Zhou Zijing , Liu Jing , Han Guangting , Ben Haoxi , Jiang Wei
Published: December 2021

Environmentally friendly face masks with high filtration efficiency are in urgent need to fight against the COVID-19 pandemic, as well as other airborne viruses, bacteria and particulate matters. In this study, coaxial electrospinning was employed to fabricate a lithium chloride enhanced cellulose acetate/thermoplastic polyurethanes (CA/TPU-LiCl) face mask nanofiber filtration membrane, which was biodegradable and reusable. The analysis results show that the CA/TPU-LiCl membrane had an excellent filtration performance: when the filtration efficiency reached 99.8%, the pressure drop was only 52 Pa. The membrane also had an outstanding reusability. The filtration performance maintained at 98.2% after 10 test cycles, and an alcohol immersion disinfection treatment showed no effect on its filtration performance. In summary, the CA/TPU-LiCl nanofiber membrane made in this work is a promising biodegradable and reusable filtration material with a wide range of potential applications, including high-performance face mask.
Graphene Oxide-Doped Polymer Inclusion Membrane for Remediation of Pharmaceutical Contaminant of Emerging Concerns: Ibuprofen
Authors: Ahmad Abdul Latif , Ebenezer Oluwasola Idowu , Shoparwe Noor Fazliani , Ismail Suzylawati
Published: December 2021

The application of polymer inclusion membranes (PIMs) for the aquatic remediation of several heavy metals, dyes, and nutrients has been extensively studied. However, its application in treating organic compounds such as Ibuprofen, an emerging pharmaceutical contaminant that poses potential environmental problems, has not been explored satisfactorily. Therefore, graphene oxide (GO) doped PIMs were fabricated, characterized, and applied to extract aqueous Ibuprofen at varied pH conditions. The doped PIMs were synthesized using a low concentration of Aliquat 336 as carrier and 0, 0.15, 0.45, and 0.75% GO as nanoparticles in polyvinyl chloride (PVC) base polymer without adding any plasticizer. The synthesized PIM was characterized by SEM, FTIR, physical, and chemical stability. The GO doped PIM was well plasticized and had an optimal Ibuprofen extraction efficiency of about 84% at pH of 10 and 0.75% GO concentration. Furthermore, the GO doped PIM’s chemical stability indicates better stability in acidic solution than in the alkaline solution. This study demonstrates that the graphene oxide-doped PIM significantly enhanced the extraction of Ibuprofen at a low concentration. However, further research is required to improve its stability and efficiency for the remediation of the ubiquitous Ibuprofen in the aquatic environment.
Comparison of Magnesium and Titanium Doping on Material Properties and pH Sensing Performance on Sb2O3 Membranes in Electrolyte-Insulator-Semiconductor Structure
Authors: Kao Chyuan-Haur , Chen Kuan-Lin , Chen Jun-Ru , Chen Shih-Ming , Kuo Yaw-Wen , Lee Ming-Ling , Lee Lukas Jyuhn-Hsiarn , Chen Hsiang
Published: December 2021

In this research, electrolyte-insulator-semiconductor (EIS) capacitors with Sb2O3 sensing membranes were fabricated. The results indicate that Mg doping and Ti-doped Sb2O3 membranes with appropriate annealing had improved material quality and sensing performance. Multiple material characterizations and sensing measurements of Mg-doped and Ti doping on Sb2O3 sensing membranes were conducted, including of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). These detailed studies indicate that silicate and defects in the membrane could be suppressed by doping and annealing. Moreover, compactness enhancement, crystallization and grainization, which reinforced the surface sites on the membrane and boosted the sensing factor, could be achieved by doping and annealing. Among all of the samples, Mg doped membrane with annealing at 400 °C had the most preferable material properties and sensing behaviors. Mg-doped Sb2O3-based with appropriate annealing are promising for future industrial ionsensing devices and for possible integration with Sb2O3-based semiconductor devices.
The Effects of Prior Austenite Grain Refinement on Strength and Toughness of High-Strength Low-Alloy Steel
Authors: Li Xiucheng , Lu Guangyi , Wang Qichen , Zhao Jingxiao , Xie Zhenjia , Misra Raja Devesh Kumar , Shang Chengjia
Published: December 2021

The effects of prior austenite grain (PAG) refinement on the mechanical properties of bainitic/martensitic steels not only come from itself, but also have more complex effects by affecting the substructure formed by coherent transformation. In this study, the samples of a low-alloy steel were water quenched from different austenitizing temperatures and the bainitic/martensitic microstructures with different PAG sizes were obtained. Electron back-scattered diffraction was used to characterize the microstructure and different types of boundaries were identified and quantitatively analyzed. The tensile tests and series temperature Charpy impact tests of different heat treatment were also carried out and comprehensively analyzed with microstructure characterization works. The results show that the uniform refinement of prior austenite grain can increases the density of packet boundary and block boundary, which leads to microstructure refinement with higher density of high-angle grain boundaries with misorientation >45°. The contribution of this microstructure refinement to toughness is significant, but its contributions to strength and elongation are relatively limited. Compared to uniform refined PAG, if the PAGs are mixed crystal, the density of block boundary will be reduced, which leads to a lower density of the high-angle boundary with misorientation >45° and the positive effects of microstructure refinement on toughness improvement are weakened. The observation of fracture surface of impact specimens indicates that refining the PAG can delay the tendency of brittle fracture with the decrease in test temperature, and even in the case of brittle fracture, the cleavage facet of the fracture surface is relatively smaller. This result also verifies that PAG refinement can effectively improve toughness by inhibiting cleavage fracture.
Morphology and Crystallography Analyses of HSLA Steels with Hardenability Enhanced by Tailored C–Ni Collocation
Authors: Liu Zhipeng , Yu Yishuang , Yang Jie , Wang Zhiquan , Guo Hui , Shang Chengjia
Published: December 2021

High hardenability is of great importance to ultra-heavy steel plates and can be achieved by tailoring the composition of steel. In this study, the continuous cooling transformation (CCT) curves of two high-strength low-alloy (HSLA) steels (0.16C-0.92Ni steel and 0.12C-1.86Ni steel) were elucidated to reveal the significance of C–Ni collocation on hardenability from the perspective of morphology and crystallography. At a low cooling rate (0.5 °C/s), the 0.12C-1.86Ni steel showed higher microhardness than 0.16C-0.92Ni steel. The microstructure in 0.16C-0.92Ni steel was mainly granular bainite with block-shaped martensite/austenite islands (M/A islands), while that in 0.12C-1.86Ni steel was typically lath bainite with film-shaped M/A islands, denoting that the 0.12C-1.86Ni steel is of higher hardenability. Moreover, the 0.12C-1.86Ni steel exhibited a higher density of block boundaries, especially V1/V2 boundaries. The higher density of block boundaries resulted from the weakened variant selection due to the larger transformation driving force and more self-accommodation of transformation strain induced by the reduced carbon and increased nickel content.
Statistical Estimation of Resistance to Cyclic Deformation of Structural Steels and Aluminum Alloy
Authors: Bazaras Žilvinas , Lukoševičius Vaidas
Published: December 2021

Resistance to cyclic loading is a key property of the material that determines the operational reliability of the structures. When selecting a material for structures operating under low-cycle loading conditions, it is essential to know the cyclic deformation characteristics of the material. Low-cycle strain diagrams are very sensitive to variations in chemical composition, thermal processing technologies, surface hardening, loading conditions, and other factors of the material. The application of probability methods enables the increase in the life characteristics of the structures and the confirmation of the cycle load values at the design phase. Most research papers dealing with statistical descriptions of low-cycle strain properties do not look into the distribution of low-cycle diagram characteristics. The purpose of our paper is to provide a probability assessment of the low-cycle properties of materials extensively used in the automotive and aviation industries, taking into account the statistical assessment of the cyclic elastoplastic strain diagrams or of the parameters of the diagrams. Materials with contrasting cyclic properties were investigated in the paper. The findings of the research allow for a review of durability and life of the structural elements of service facilities subjected to elastoplastic loading by assessing the distribution of low-cycle strain parameters, as well as the allowed distribution limits.
Prediction of Healthy Pregnancy Outcomes in Women with Overweight and Obesity: The Role of Maternal Early-Pregnancy Metabolites
Authors: Wahab Rama J. , Jaddoe Vincent W. V. , Gaillard Romy
Published: December 2021

Women with obesity receive intensified antenatal care due to their increased risk of pregnancy complications, even though not all of these women develop complications. We developed a model based on maternal characteristics for prediction of healthy pregnancy outcomes in women with obesity or who are overweight. We assessed whether early-pregnancy metabolites improved prediction. In a population-based cohort study among a subsample of 1180 Dutch pregnant women with obesity or who are overweight, we developed a prediction model using 32 maternal socio-demographic, lifestyle, physical and pregnancy-related characteristics. We determined early-pregnancy amino acids, nonesterifed fatty acids, phospholipids and carnitines in blood serum using liquid chromatography-tandem mass spectrometry. A healthy pregnancy outcome was the absence of fetal death, gestational hypertension, preeclampsia, gestational diabetes, caesarian section, preterm birth, large-for-gestational-age at birth, macrosomia, postpartum weight retention and offspring overweight/obesity at 5 years. Maternal age, relationship status, parity, early-pregnancy body mass index, mid-pregnancy gestational weight gain, systolic blood pressure and estimated fetal weight were selected into the model using backward selection (area under the receiver operating characteristic curve: 0.65 (95% confidence interval 0.61 to 0.68)). Early-pregnancy metabolites did not improve model performance. Thus, in women with obesity or who are overweight, maternal characteristics can moderately predict a healthy pregnancy outcome. Maternal early-pregnancy metabolites have no incremental value in the prediction of a healthy pregnancy outcome.
The Correlation between Extracellular Heat Shock Protein 70 and Lipid Metabolism in a Ruminant Model
Authors: Petrović Miloš Ž. , Cincović Marko , Starič Jože , Djoković Radojica , Belić Branislava , Radinović Miodrag , Majkić Mira , Ilić Zoran Ž.
Published: December 2021

Metabolic stress in early lactation cows is characterized by lipolysis, ketogenesis, insulin resistance and inflammation because of negative energy balance and increased use of lipids for energy needs. In this study the relationship between lipid metabolite, lipid-based insulin resistance, and hepatocyte functionality indexes and tumor necrosis factor alpha (TNF-α) with extracellular heat shock protein 70 (eHsp70) was investigated. The experiment included 50 cows and all parameters were measured in blood serum. In cows with a more pronounced negative energy balance, the following was determined: a higher concentration of eHsp70, TNF-α, non-esterified fatty acid (NEFA), beta-hydroxybutyrate (BHB), NEFA to insulin and NEFA to cholesterol ratio and lower concentration of cholesterol, very low-density lipoproteins (VLDL), low density lipoproteins (LDL) and liver functionality index (LFI). The eHsp70 correlated negatively with the values of cholesterol, VLDL, LDL, and triglycerides, while correlated positively with the level of NEFA and BHB. A higher concentration of eHsp70 suggests the development of fatty liver (due to a higher NEFA to cholesterol ratio and lower LFI) and insulin resistance (due to a lower revised quantitative insulin sensitivity check index RQUICKI-BHB and higher NEFA to insulin ratio). The eHsp70 correlated positively with TNF-α. Both TNF-α and eHsp70 correlated similarly to lipid metabolites. In cows with high eHsp70 and TNF-α values we found higher concentrations of NEFA, BHB, NEFA to insulin and NEFA to cholesterol ratio and a lower concentration of triglycerides and VLDL cholesterol compared to cows that had only high TNF-α values. Based on the positive correlation between eHsp70 and TNF-α, their similar relations, and the additional effect of eHsp70 (high TNF-α + eHsp70 values) on lipid metabolites we conclude that eHsp70 has pro-inflammatory effects implicating lipolysis, fatty liver, and fat tissue insulin resistance.
Design of a 3DOF XYZ Bi-Directional Motion Platform Based on Z-Shaped Flexure Hinges
Authors: Gan Jinqiang , Long Jiarong , Ge Ming-Feng
Published: December 2021

This paper presents a design of a 3DOF XYZ bi-directional motion platform based on Z-shaped flexure hinges. In the presented platform, bridge-type mechanisms and Z-shaped flexure hinges are adopted to amplify its output displacement. Bi-direction motion along the X-axis and Y-axis follows the famous differential moving principle DMP, and the bi-directional motion along the Z-axis is realized by using the reverse arrangement of the Z-shaped flexure hinges along the X-axis and Y-axis. Statics analysis of the proposed platform is carried out by the energy method, compliance matrix method, and force balance principle. Meanwhile, the Lagrange method is used to analyze the dynamics of the platform. A series of simulations are conducted to demonstrate the effectiveness of the proposed design. The simulation results show that the average displacements of the platform in the XYZ-axis are ±125.58 μm, ±126.37 μm and ±568.45 μm, respectively.
Self-Assembled 1-Octadecanethiol Membrane on Pd/ZnO for a Selective Room Temperature Flexible Hydrogen Sensor
Authors: Pathak Pawan , Cho Hyoung Jin
Published: December 2021

A layer of self-assembled 1-octadecanethiol was used to fabricate a palladium (Pd)/zinc oxide (ZnO) nanoparticle-based flexible hydrogen sensor with enhanced response and high selectivity at room temperature. A palladium film was first deposited using DC sputtering technique and later annealed to form palladium nanoparticles. The formation of uniform, surfactant-free palladium nanoparticles contributed to improved sensor response towards hydrogen gas at room temperature. The obtained sensor response was higher than for previously reported room temperature Pd/ZnO sensors. Furthermore, the use of the polymer membrane suppressed the sensor’s response to methane, moisture, ethanol, and acetone, resulting in the selective detection of hydrogen in the presence of the common interfering species. This study shows a viable low-cost fabrication pathway for highly selective room temperature flexible hydrogen sensors for hydrogen-powered vehicles and other clean energy applications.
Electrical and Optical Doping of Silicon by Pulsed-Laser Melting
Authors: Lim Shao Qi , Williams James S.
Published: December 2021

Over four decades ago, pulsed-laser melting, or pulsed-laser annealing as it was termed at that time, was the subject of intense study as a potential advance in silicon device processing. In particular, it was found that nanosecond laser melting of the near-surface of silicon and subsequent liquid phase epitaxy could not only very effectively remove lattice disorder following ion implantation, but could achieve dopant electrical activities exceeding equilibrium solubility limits. However, when it was realised that solid phase annealing at longer time scales could achieve similar results, interest in pulsed-laser melting waned for over two decades as a processing method for silicon devices. With the emergence of flat panel displays in the 1990s, pulsed-laser melting was found to offer an attractive solution for large area crystallisation of amorphous silicon and dopant activation. This method gave improved thin film transistors used in the panel backplane to define the pixelation of displays. For this application, ultra-rapid pulsed laser melting remains the crystallisation method of choice since the heating is confined to the silicon thin film and the underlying glass or plastic substrates are protected from thermal degradation. This article will be organised chronologically, but treatment naturally divides into the two main topics: (1) an electrical doping research focus up until around 2000, and (2) optical doping as the research focus after that time. In the first part of this article, the early pulsed-laser annealing studies for electrical doping of silicon are reviewed, followed by the more recent use of pulsed-lasers for flat panel display fabrication. In terms of the second topic of this review, optical doping of silicon for efficient infrared light detection, this process requires deep level impurities to be introduced into the silicon lattice at high concentrations to form an intermediate band within the silicon bandgap. The chalcogen elements and then transition metals were investigated from the early 2000s since they can provide the required deep levels in silicon. However, their low solid solubilities necessitated ultra-rapid pulsed-laser melting to achieve supersaturation in silicon many orders of magnitude beyond the equilibrium solid solubility. Although infrared light absorption has been demonstrated using this approach, significant challenges were encountered in attempting to achieve efficient optical doping in such cases, or hyperdoping as it has been termed. Issues that limit this approach include: lateral and surface impurity segregation during solidification from the melt, leading to defective filaments throughout the doped layer; and poor efficiency of collection of photo-induced carriers necessary for the fabrication of photodetectors. The history and current status of optical hyperdoping of silicon with deep level impurities is reviewed in the second part of this article.
Commensal and Opportunistic Bacteria Present in the Microbiota in Atlantic Cod (Gadus morhua) Larvae Differentially Alter the Hosts’ Innate Immune Responses
Authors: Vestrum Ragnhild Inderberg , Forberg Torunn , Luef Birgit , Bakke Ingrid , Winge Per , Olsen Yngvar , Vadstein Olav
Published: December 2021

The roles of host-associated bacteria have gained attention lately, and we now recognise that the microbiota is essential in processes such as digestion, development of the immune system and gut function. In this study, Atlantic cod larvae were reared under germ-free, gnotobiotic and conventional conditions. Water and fish microbiota were characterised by 16S rRNA gene analyses. The cod larvae’s transcriptional responses to the different microbial conditions were analysed by a custom Agilent 44 k oligo microarray. Gut development was assessed by transmission electron microscopy (TEM). Water and fish microbiota differed significantly in the conventional treatment and were dominated by different fast-growing bacteria. Our study indicates that components of the innate immune system of cod larvae are downregulated by the presence of non-pathogenic bacteria, and thus may be turned on by default in the early larval stages. We see indications of decreased nutrient uptake in the absence of bacteria. The bacteria also influence the gut morphology, reflected in shorter microvilli with higher density in the conventional larvae than in the germ-free larvae. The fact that the microbiota alters innate immune responses and gut morphology demonstrates its important role in marine larval development.
Wine Yeasts 1.0
Authors: Sipiczki Matthias
Published: December 2021

The conversion of grape juice into wine is a complex biochemical process involving alcoholic fermentation, production of wide range of metabolites and interactions of yeast strains, bacteria and fungi [...]
The Darkest Place Is under the Candlestick-Healthy Urogenital Tract as a Source of Worldwide Disseminated Extraintestinal Pathogenic Escherichia coli Lineages
Authors: Ksiezarek Magdalena , Novais Ângela , Peixe Luísa
Published: December 2021

Since the discovery of the urinary microbiome, including the identification of Escherichia coli in healthy hosts, its involvement in UTI development has been a subject of high interest. We explored the population diversity and antimicrobial resistance of E. coli (n = 22) in the urogenital microbiome of ten asymptomatic women (representing 50% of the sample tested). We evaluated their genomic relationship with extraintestinal pathogenic E. coli (ExPEC) strains from healthy and diseased hosts, including the ST131 lineage. E. coli prevalence was higher in vaginal samples than in urine samples, and occasionally different lineages were observed in the same individual. Furthermore, B2 was the most frequent phylogenetic group, with the most strains classified as ExPEC. Resistance to antibiotics of therapeutic relevance (e.g., amoxicillin-clavulanate conferred by blaTEM-30) was observed in ExPEC widespread lineages sequence types (ST) 127, ST131, and ST73 and ST95 clonal complexes. Phylogenomics of ST131 and other ExPEC lineages revealed close relatedness with strains from gastrointestinal tract and diseased host. These findings demonstrate that healthy urogenital microbiome is a source of potentially pathogenic and antibiotic resistant E. coli strains, including those causing UTI, e.g., ST131. Importantly, diverse E. coli lineages can be observed per individual and urogenital sample type which is relevant for future studies screening for this uropathogen.
Characterization of the Proteolytic Activity of a Halophilic Aspergillus reticulatus Strain SK1-1 Isolated from a Solar Saltern
Authors: Chung Dawoon , Yu Woon-Jong , Lim Ji-Yeon , Kang Nam-Seon , Kwon Yong-Min , Choi Grace , Bae Seung-Sub , Cho Kichul , Lee Dae-Sung
Published: December 2021

Salterns are hypersaline environments that are inhabited by diverse halophilic microorganisms, including fungi. In this study, we isolated a fungal strain SK1-1 from a saltern in the Republic of Korea, which was identified as Asperillus reticulatus. This is the first reported saline-environment-derived A. reticulatus that belongs to the Aspergillus penicillioides clade and encompasses xerophilic fungi. SK1-1 was halophilic, obligately requiring NaCl for growth, with a maximum radial growth of 6%–9% (w/v) NaCl. To facilitate the biotechnological application of halophilic fungi, we screened the SK1-1 strain for proteolytic activity. Proteases have widespread applications in food processing, detergents, textiles, and waste treatment, and halophilic proteases can enable protein degradation in high salt environments. We assessed the proteolytic activity of the extracellular crude enzyme of SK1-1 using azocasein as a substrate. The crude protease exhibited maximum activity at 40–50 °C, pH 9.5–10.5, and in the absence of NaCl. It was also able to retain up to 69% of its maximum activity until 7% NaCl. Protease inhibitor assays showed complete inhibition of the proteolytic activity of crude enzymes by Pefabloc® SC. Our data suggest that the halophilic A. reticulatus strain SK1-1 produces an extracellular alkaline serine protease.
Genetic Engineering of Streptomyces ghanaensis ATCC14672 for Improved Production of Moenomycins
Authors: Makitrynskyy Roman , Tsypik Olga , Bechthold Andreas
Published: December 2021

Streptomycetes are soil-dwelling multicellular microorganisms famous for their unprecedented ability to synthesize numerous bioactive natural products (NPs). In addition to their rich arsenal of secondary metabolites, Streptomyces are characterized by complex morphological differentiation. Mostly, industrial production of NPs is done by submerged fermentation, where streptomycetes grow as a vegetative mycelium forming pellets. Often, suboptimal growth peculiarities are the major bottleneck for industrial exploitation. In this work, we employed genetic engineering approaches to improve the production of moenomycins (Mm) in Streptomyces ghanaensis, the only known natural direct inhibitors of bacterial peptidoglycan glycosyltransferses. We showed that in vivo elimination of binding sites for the pleiotropic regulator AdpA in the oriC region strongly influences growth and positively correlates with Mm accumulation. Additionally, a marker- and “scar”-less deletion of moeH5, encoding an amidotransferase from the Mm gene cluster, significantly narrows down the Mm production spectrum. Strikingly, antibiotic titers were strongly enhanced by the elimination of the pleiotropic regulatory gene wblA, involved in the late steps of morphogenesis. Altogether, we generated Mm overproducers with optimized growth parameters, which are useful for further genome engineering and chemoenzymatic generation of novel Mm derivatives. Analogously, such a scheme can be applied to other Streptomyces spp.
Complete Genome Sequence, Molecular Characterization and Phylogenetic Relationships of a Novel Tern Atadenovirus
Authors: Matsvay Alina , Dyachkova Marina , Mikhaylov Ivan , Kiselev Daniil , Say Anna , Burskaia Valentina , Artyushin Ilya , Khafizov Kamil , Shipulin German
Published: December 2021

Discovery and study of viruses carried by migratory birds are tasks of high importance due to the host’s ability to spread infectious diseases over significant distances. With this paper, we present and characterize the first complete genome sequence of atadenovirus from a tern bird (common tern, Sterna hirundo) preliminarily named tern atadenovirus 1 (TeAdV-1). TeAdV-1 genome is a linear double-stranded DNA molecule, 31,334 base pairs which contain 30 methionine-initiated open reading frames with gene structure typical for Atadenovirus genus, and the shortest known inverted terminal repeats (ITRs) within the Atadenovirus genus consisted of 25 bases. The nucleotide composition of the genome is characterized by a low G + C content (33.86%), which is the most AT-rich genome of known avian adenoviruses within Atadenovirus genus. The nucleotide sequence of the TeAdV-1 genome shows high divergence compared to known representatives of the Atadenovirus genus with the highest similarity to the duck atadenovirus 1 (53.7%). Phylogenetic analysis of the protein sequences of core genes confirms the taxonomic affiliation of the new representative to the genus Atadenovirus with the degree of divergence from the known representatives exceeding the interspecies distance within the genus. Thereby we proposed a novel TeAdV-1 to be considered as a separate species.