bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular Network for Regulation of Ovule Number in Plants
Authors: Qadir Muslim , Wang Xinfa , Shah Syed Rehmat Ullah , Zhou Xue-Rong , Shi Jiaqin , Wang Hanzhong
Published: December 2021

In seed-bearing plants, the ovule (“small egg”) is the organ within the gynoecium that develops into a seed after fertilization. The gynoecium located in the inner compartment of the flower turns into a fruit. The number of ovules in the ovary determines the upper limit or the potential of seed number per fruit in plants, greatly affecting the final seed yield. Ovule number is an important adaptive characteristic for plant evolution and an agronomic trait for crop improvement. Therefore, understanding the mechanism and pathways of ovule number regulation becomes a significant research aspect in plant science. This review summarizes the ovule number regulators and their regulatory mechanisms and pathways. Specially, an integrated molecular network for ovule number regulation is constructed, in which phytohormones played a central role, followed by transcription factors, enzymes, other protein and micro-RNA. Of them, AUX, BR and CK are positive regulator of ovule number, whereas GA acts negatively on it. Interestingly, many ovule number regulators have conserved functions across several plant taxa, which should be the targets of genetic improvement via breeding or gene editing. Many ovule number regulators identified to date are involved in the diverse biological process, such as ovule primordia formation, ovule initiation, patterning, and morphogenesis. The relations between ovule number and related characteristics/traits especially of gynoecium/fruit size, ovule fertility, and final seed number, as well as upcoming research questions, are also discussed. In summary, this review provides a general overview of the present finding in ovule number regulation, which represents a more comprehensive and in-depth cognition on it.
Enmein Decreases Synaptic Glutamate Release and Protects against Kainic Acid-Induced Brain Injury in Rats
Authors: Lu Cheng-Wei , Huang Yu-Chen , Chiu Kuan-Ming , Lee Ming-Yi , Lin Tzu-Yu , Wang Su-Jane
Published: December 2021

This study investigated the effects of enmein, an active constituent of Isodon japonicus Hara, on glutamate release in rat cerebrocortical nerve terminals (synaptosomes) and evaluated its neuroprotective potential in a rat model of kainic acid (KA)-induced glutamate excitotoxicity. Enmein inhibited depolarization-induced glutamate release, FM1-43 release, and Ca2+ elevation in cortical nerve terminals but had no effect on the membrane potential. Removing extracellular Ca2+ and blocking vesicular glutamate transporters, N- and P/Q-type Ca2+ channels, or protein kinase C (PKC) prevented the inhibition of glutamate release by enmein. Enmein also decreased the phosphorylation of PKC, PKC-α, and myristoylated alanine-rich C kinase substrates in synaptosomes. In the KA rat model, intraperitoneal administration of enmein 30 min before intraperitoneal injection of KA reduced neuronal cell death, glial cell activation, and glutamate elevation in the hippocampus. Furthermore, in the hippocampi of KA rats, enmein increased the expression of synaptic markers (synaptophysin and postsynaptic density protein 95) and excitatory amino acid transporters 2 and 3, which are responsible for glutamate clearance, whereas enmein decreased the expression of glial fibrillary acidic protein (GFAP) and CD11b. These results indicate that enmein not only inhibited glutamate release from cortical synaptosomes by suppressing Ca2+ influx and PKC but also increased KA-induced hippocampal neuronal death by suppressing gliosis and decreasing glutamate levels by increasing glutamate uptake.
Natural Gums as Oleogelators
Authors: Banaś Karol , Harasym Joanna
Published: December 2021

The natural gums used as high molecular weight oleogelators are mainly polysaccharides that deliver a broad spectrum of possible utilization methods when structuring liquid fats to solid forms. The review discusses a natural gums’ structuring and gelling behavior to capture the oil droplets and form the water/oil gelling emulsions basing on their structural conformation, internal charge, and polymeric characteristics. The specific parameters and characteristics of natural gums based oleogels are also discussed. In the future, oleogels may eliminate saturated and trans fats from food products and allow the production of low-fat products, thus reducing the environmental damage caused by the excessive use of palm oil. The increasing knowledge of molecular interaction in polysaccharide chains of natural gums allows to apply more sustainable and wiser strategies towards product formulation. Innovative solutions for using oleogels based on natural polysaccharide biopolymers let incorporate them into the food matrix and replace fats completely or create blends containing the source of fats and the addition of the oleogel. The profound insight into molecular characteristics of natural gums in the function of being oleogelators is presented.
Kinetic Study on the Reactivity of Azanone (HNO) toward Cyclic C-Nucleophiles
Authors: Artelska Angelika , Rola Monika , Rostkowski Michał , Pięta Marlena , Pięta Jakub , Michalski Radosław , Sikora Adam Bartłomiej
Published: December 2021

Azanone (HNO) is an elusive electrophilic reactive nitrogen species of growing pharmacological and biological significance. Here, we present a comparative kinetic study of HNO reactivity toward selected cyclic C-nucleophiles under aqueous conditions at pH 7.4. We applied the competition kinetics method, which is based on the use of a fluorescein-derived boronate probe FlBA and two parallel HNO reactions: with the studied scavenger or with O2 (k = 1.8 × 104 M−1s−1). We determined the second-order rate constants of HNO reactions with 13 structurally diverse C-nucleophiles (k = 33–20,000 M−1s−1). The results show that the reactivity of HNO toward C-nucleophiles depends strongly on the structure of the scavenger. The data are supported with quantum mechanical calculations. A comprehensive discussion of the HNO reaction with C-nucleophiles is provided.
Truncation-Driven Lateral Association of α-Synuclein Hinders Amyloid Clearance by the Hsp70-Based Disaggregase
Authors: Franco Aitor , Cuéllar Jorge , Fernández-Higuero José Ángel , de la Arada Igor , Orozco Natalia , Valpuesta José M. , Prado Adelina , Muga Arturo
Published: December 2021

The aggregation of α-synuclein is the hallmark of a collective of neurodegenerative disorders known as synucleinopathies. The tendency to aggregate of this protein, the toxicity of its aggregation intermediates and the ability of the cellular protein quality control system to clear these intermediates seems to be regulated, among other factors, by post-translational modifications (PTMs). Among these modifications, we consider herein proteolysis at both the N- and C-terminal regions of α-synuclein as a factor that could modulate disassembly of toxic amyloids by the human disaggregase, a combination of the chaperones Hsc70, DnaJB1 and Apg2. We find that, in contrast to aggregates of the protein lacking the N-terminus, which can be solubilized as efficiently as those of the WT protein, the deletion of the C-terminal domain, either in a recombinant context or as a consequence of calpain treatment, impaired Hsc70-mediated amyloid disassembly. Progressive removal of the negative charges at the C-terminal region induces lateral association of fibrils and type B* oligomers, precluding chaperone action. We propose that truncation-driven aggregate clumping impairs the mechanical action of chaperones, which includes fast protofilament unzipping coupled to depolymerization. Inhibition of the chaperone-mediated clearance of C-truncated species could explain their exacerbated toxicity and higher propensity to deposit found in vivo.
Interleukin-35 Prevents Development of Autoimmune Diabetes Possibly by Maintaining the Phenotype of Regulatory B Cells
Authors: Luo Zhengkang , Lundin Sara , Mejia-Cordova Mariela , Hassani Imane , Blixt Martin , Hjelmqvist Daisy , Lau Joey , Espes Daniel , Carlsson Per-Ola , Sandler Stellan , Singh Kailash
Published: December 2021

The anti-inflammatory role of regulatory B cells (Breg cells) has been associated with IL-35 based on studies of experimental autoimmune uveitis and encephalitis. The role of Breg cells and IL-35+ Breg cells for type 1 diabetes (T1D) remains to be investigated. We studied PBMCs from T1D subjects and healthy controls (HC) and found lowered proportions of Breg cells and IL-35+ Breg cells in T1D. To elucidate the role of Breg cells, the lymphoid organs of two mouse models of T1D were examined. Lower proportions of Breg cells and IL-35+ Breg cells were found in the animal models of T1D compared with control mice. In addition, the systemic administration of recombinant mouse IL-35 prevented hyperglycemia after multiple low dose streptozotocin (MLDSTZ) injections and increased the proportions of Breg cells and IL-35+ Breg cells. A higher proportion of IFN-γ+ cells among Breg cells were found in the PBMCs of the T1D subjects. In the MLDSTZ mice, IL-35 administration decreased the proportions of IFN-γ+ cells among the Breg cells. Our data illustrate that Breg cells may play an important role in the development of T1D and that IL-35 treatment prevents the development of hyperglycemia by maintaining the phenotype of the Breg cells under an experimental T1D condition.
Identification of SCN5a p.C335R Variant in a Large Family with Dilated Cardiomyopathy and Conduction Disease
Authors: Sedaghat-Hamedani Farbod , Rebs Sabine , El-Battrawy Ibrahim , Chasan Safak , Krause Tobias , Haas Jan , Zhong Rujia , Liao Zhenxing , Xu Qiang , Zhou Xiaobo , Akin Ibrahim , Zitron Edgar , Frey Norbert , Streckfuss-Bömeke Katrin , Kayvanpour Elham
Published: December 2021

Introduction: Familial dilated cardiomyopathy (DCM) is clinically variable and has been associated with mutations in more than 50 genes. Rapid improvements in DNA sequencing have led to the identification of diverse rare variants with unknown significance (VUS), which underlines the importance of functional analyses. In this study, by investigating human-induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs), we evaluated the pathogenicity of the p.C335R sodium voltage-gated channel alpha subunit 5 (SCN5a) variant in a large family with familial DCM and conduction disease. Methods: A four-generation family with autosomal dominant familial DCM was investigated. Next-generation sequencing (NGS) was performed in all 16 family members. Clinical deep phenotyping, including endomyocardial biopsy, was performed. Skin biopsies from two patients and one healthy family member were used to generate human-induced pluripotent stem cells (iPSCs), which were then differentiated into cardiomyocytes. Patch-clamp analysis with Xenopus oocytes and iPSC-CMs were performed. Results: A SCN5a variant (c.1003T>C; p.C335R) could be detected in all family members with DCM or conduction disease. A novel truncating TTN variant (p.Ser24998LysfsTer28) could also be identified in two family members with DCM. Family members with the SCN5a variant (p.C335R) showed significantly longer PQ and QRS intervals and lower left ventricular ejection fractions (LV-EF). All four patients who received CRT-D were non-responders. Electrophysiological analysis with Xenopus oocytes showed a loss of function in SCN5a p.C335R. Na+ channel currents were also reduced in iPSC-CMs from DCM patients. Furthermore, iPSC-CM with compound heterozygosity (SCN5a p.C335R and TTNtv) showed significant dysregulation of sarcomere structures, which may be contributed to the severity of the disease and earlier onset of DCM. Conclusion: The SCN5a p.C335R variant is causing a loss of function of peak INa in patients with DCM and cardiac conduction disease. The co-existence of genetic variants in channels and structural genes (e.g., SCN5a p.C335R and TTNtv) increases the severity of the DCM phenotype.
Potential Roles of Modified Pectin Targeting Galectin-3 against Severe Acute Respiratory Syndrome Coronavirus-2
Authors: Odun-Ayo Frederick , Reddy Lalini
Published: December 2021

Modified pectin (MP) is a bioactive complex polysaccharide that is broken down into smaller fragments of units and used as an oral dietary supplement for cell proliferation. MP is safe and non-toxic with promising therapeutic properties with regard to targeting galectin-3 (GAL-3) toward the prevention and inhibition of viral infections through the modulation of the immune response and anti-inflammatory cytokine effects. This effect of MP as a GAL-3 antagonism, which has shown benefits in preclinical and clinical models, may be of relevance to the progression of the novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in coronavirus disease 2019 patients. The outbreak of emerging infectious diseases continues to pose a threat to human health. Further to the circulation of multiple variants of SARS-CoV-2, an effective and alternative therapeutic approach to combat it has become pertinent. The use of MP as a GAL-3 inhibitor could serve as an antiviral agent blocking against the SARS-CoV-2-binding spike protein. This review highlights the potential effects of MP in viral infections, its proposed role as a GAL-3 inhibitor, and the associated function concerning a SARS-CoV-2 infection.
Immunogenicity of BNT162b2 mRNA COVID-19 Vaccine in Patients with Cardiovascular Disease
Authors: Naruse Hiroyuki , Ito Hiroyasu , Izawa Hideo , Sarai Masayoshi , Ishii Junnichi , Sakaguchi Eirin , Murakami Reiko , Ando Tatsuya , Fujigaki Hidetsugu , Saito Kuniaki
Published: December 2021

Concern has been raised about the effectiveness of the coronavirus disease 2019 (COVID-19) vaccine in the population of patients with various comorbidities such as heart disease. We investigated the humoral response to the BNT162b2 mRNA COVID-19 vaccine in patients with cardiovascular disease (CVD). We measured IgG against severe acute respiratory syndrome coronavirus 2 spike receptor-binding domain (RBD-IgG) in 85 CVD patients and 179 healthcare workers (HCWs). Blood samples were collected from patients and HCWs three times: (1) before the first dose of vaccination, (2) two weeks after the first dose of vaccination, and (3) two weeks after the second dose of vaccination. Patients with CVD showed a significantly inferior serological response to the BNT162b2 mRNA COVID-19 vaccine at 14 days after the prime dose compared to HCWs (21% vs. 95%, p < 0.001). Median RBD-IgG titers of patients with CVD at 14 days after the second dose were significantly lower than those of HCWs (137.2 U/mL (80.6–200.4 U/mL) vs. 176.2 U/mL (123.9–260.0 U/mL), p < 0.001). In multivariable analyses, CVD is significantly associated with seropositivity after first vaccination and RBD-IgG titers after second vaccination. CVD patients may have a poor humoral response to the BNT162b2 mRNA COVID-19 vaccine, need to be closely monitored, and require earlier revaccination to ensure stronger immunity and protection against infection.
Diagnostic Re-Evaluation and Potential Predictor Factors of Transient and Permanent Congenital Hypothyroidism in Eutopic Thyroid Gland
Authors: Tuli Gerdi , Munarin Jessica , De Sanctis Luisa
Published: December 2021

Background: The incidence of congenital hypothyroidism (CH) has increased over the years, and many predictors for detecting newborns with transient forms (TCH) as early as possible have been considered. Methods: All newborns diagnosed with primary CH and eutopic gland in the Piedmont region of Italy in the period of January 2014–June 2019 were enrolled and re-evaluated at the age of 2 years. Results: 105 newborns were diagnosed with CH during the study period. Dyshormonogenesis was observed in 55/105. At re-evaluation, we found that 52.7% had permanent CH (PCH), while 47.3% had TCH. Male/female rate, TSH levels at diagnosis, levothyroxine requirement at withdrawal and extra-thyroid congenital malformations rate were higher in the PCH group (p = 0.02, p = 0.009, p = 0.02 and p = 0.01), while fT4 levels at diagnosis were lower (p = 0.03). Sensitivity of 72.4% and specificity of 80.7% for serum TSH above 60 mcUI/mL, sensitivity of 73% and specificity of 72.4% for serum fT4 level below 7.2 pg/mL and sensitivity of 66% and specificity of 68% for drug requirement above 2.25 mcg/kg/day were observed in PCH. Conclusions: Demographic, clinical and hormonal data at diagnosis and levothyroxine requirement during the first two years should be adequately monitored to identify infants who are most likely to discontinue therapy after the age of 24 months.
FE-Simulation Based Design of Wear-Optimized Cutting Edge Roundings
Authors: Bergmann Benjamin , Denkena Berend , Beblein Sascha , Picker Tobias
Published: December 2021

The performance of cutting tools can be significantly enhanced by matching the cutting edge rounding to the process and material properties. However, the conventional cutting edge rounding design is characterized by a significant number of experimental machining studies, which involve considerable cost, time, and resources. In this study, a novel approach to cutting edge rounding design using FEM-based chip formation simulations is presented. Based on a parameterized simulation model, tool temperatures, stresses and relative velocities can be calculated as a function of tool microgeometry. It can be shown that the external tool loads can be simulated with high agreement. With the help of these loads and the use of wear models, the resulting tool wear and the optimum cutting edge rounding can be determined. The final experimental investigations show a qualitatively high agreement to the simulation, which will enable a reduced effort design of the cutting edge in the future.
High-Precision Adjustment of Welding Depth during Laser Micro Welding of Copper Using Superpositioned Spatial and Temporal Power Modulation
Authors: Hummel Marc , Häusler André , Gillner Arnold
Published: December 2021

For joining metallic materials for battery applications such as copper and stainless steel, laser beam micro welding with beam sources in the near-infrared range has become established in recent years. In laser beam micro welding, spatial power modulation describes the superposition of the linear feed motion with an oscillating motion. This modulation method serves to widen the cross-section of the weld seam as well as to increase the process stability. Temporal power modulation refers to the controlled modulation of the laser power over time during the welding process. In this paper, the superposition of both temporal and spatial power modulation methods is presented, which enables a variable control of the weld penetration depth. Three weld geometries transverse to the feed direction are part of this investigation: the compensation of the weld penetration depth due to the asymmetric path movement during spatial power modulation only, a W-shaped weld profile, and a V-shaped. The weld geometries are investigated by the bed on plate weld tests with CuSn6. Furthermore, the use of combined power modulation for welding tests in butt joint configuration between CuSn6 and stainless steel 1.4301 with different material properties is investigated. The study shows the possibility of precise control of the welding depth by this methodology. Depending on the material combination, the desired regions with maximum and minimum welding depth can be achieved by the control of local and temporal power modulation on the material surface.
Development of a Cost Model for Vertical Milling Machines to Assess Impact of Lightweighting
Authors: Triebe Matthew J. , Zhao Fu , Sutherland John W.
Published: December 2021

Lightweighting is a design strategy to reduce energy consumption through the reduction of mass of a product. Lightweighting can be applied to machine tools to reduce the amount of energy consumed during the use phase. Thus, the energy cost of machine operation will be reduced. One might also hypothesize that since a lighter-weight machine tool requires less material to build, the cost to produce such a machine will be less. However, it may also be the case that lightweighting a machine tool increases its complexity, which will likely drive up the cost to manufacture the machine. To explore the cost drivers associated with building a machine tool, data on the features associated with a wide variety of vertical milling machine tools are collected. Then, empirical cost models are fit to this data. The results from the cost models show that the machine tool mass is a significant cost driver; other key drivers are the number of axes and spindle power. The models are used to predict the cost benefits of lightweighting in terms of mass, which are compared to potential increased manufacturing costs associated with complexities introduced due to lightweighting.
Prospects of Extracellular Vesicles in Otorhinolaryngology, Head and Neck Surgery
Authors: Sluga Metka , Battelino Saba , Vozel Domen
Published: December 2021

The diagnostic and therapeutic potential of extracellular vesicles (EVs) has been recognised in many fields of medicine for several years. More recently, it has become a topic of increasing interest in otorhinolaryngology, head and neck surgery (ORL-HNS). With this narrative review, we have aspired to determine different aspects of those nanometrically sized theranostic particles, which seem to have promising potential as biomarkers in some of the most common diseases of the ORL-HNS by being available via less invasive diagnostic methods. At the same time, a better understanding of their activity provides us with new possibilities for developing specific target treatments. So far, most research has been oriented towards the role of EVs in the progression of head and neck cancer, notably head and neck squamous cell cancer. Nonetheless, some of this research has focused on chronic diseases of the ears, nose and paranasal sinuses. However, most research is still in the preclinical or experimental phase. It therefore requires a further and more profound understanding of EV content and behaviour to utilise their nanotheranostic capacities to their fullest potential.
The Role of Investor Relations and Good Corporate Governance on Firm Performance in the Case of the Companies Listed on the Bucharest Stock Exchange
Authors: Mihail Bogdan Aurelian , Dumitrescu Dalina , Serban Daniela , Micu Carmen Daniela , Lobda Adriana
Published: December 2021

The objective of this paper is to investigate the role of Investor Relations (IR) in the performance of companies listed on the Bucharest Stock Exchange. The study is motivated by the findings in the literature that investor relations may boost information disclosure, analyst following, institutional investor share, liquidity, and business valuation. The current article contributes to the relevant literature by making use of the recently released unique database of VEKTOR scores on company investor relations for 2019 and 2020. The main finding based on regression methodology shows that IR scores have a strong positive relationship with firm performance. Specifically, a one standard deviation rise in the IR score corresponds to a 2.6% rise in company ROA. Companies may be advised to strengthen their investor relations based on these findings about the beneficial role of investor relations.
Meshing Sustainability with Satisfaction: An Investigation of Residents’ Perceptions in Three Different Neighbourhoods in Chengdu, China
Authors: Zhang Qi , Hiu-Kwan Yung Esther , Hon-Wan Chan Edwin
Published: December 2021

Can sustainability and liveability be simultaneously pursued at the neighbourhood level? Adopting neighbourhood satisfaction as a proxy to indicate liveability at the neighbourhood scale, this paper investigated how the residential subjective perception of sustainability factors interacted with neighbourhood satisfaction in the context of three different neighbourhoods in Chengdu, China. This began with a comprehensive literature review to construct the neighbourhood sustainability framework. Then, a total of 510 cross-sectional questionnaire surveys was conducted in Chengdu. Logistic regression was employed to investigate significant associations. The findings revealed that the ‘sense and habit of energy saving’ is the only sustainability factor that is negatively associated with neighbourhood satisfaction in commodity-housing neighbourhood. Compared with intangible factors, tangible or physical sustainability factors are more likely to contribute to improving neighbourhood satisfaction and suppressing moving intention. The study also evidenced the contextual differences of significant associations among danwei, resettlement, and commodity-housing neighbourhoods coexisting in transitional China. This calls for adaptive and contextual rather than standardized, top-down strategies for developing sustainable neighbourhood planning to simultaneously promote sustainability and liveability in Chengdu, China. Finally, a specific contextual framework was provided as policy implications for developing local and adaptive solutions.
Residents’ Demands for Urban Retail: Heterogeneity in Housing Structure Characteristics, Price Quantile, and Space
Authors: Ren Pengyu , Li Yuanli , You Kairui
Published: December 2021

A thorough understanding of residents’ demands plays an important role in realizing the rational distribution of urban retail (UR) and promoting the habitability of cities. Unfortunately, these demands for UR are currently under-researched. To solve this problem, this study aims to quantify the capitalization effect of UR on housing prices and explores the impact of heterogeneity in housing structure characteristics, price quantile, and space on the residents’ demands for UR according to the hedonic price model, quantile regression, and geographically weighted regression in Chengdu. The results of these models show the following: (1) good property management and building sound insulation can reduce the negative influence of UR on residents’ lives; (2) only the owners of low-price houses are willing to pay a premium for UR; and (3) residents’ demands for UR increase from the central area to the peripheral area of Chengdu, and an inverted U-shaped relationship was found between housing prices and the UR level. A comprehensive analysis of the heterogeneity of residents’ demands for UR can provide a reference for planning departments, real-estate developers, and UR owners and promote the sustainable development of UR.
Rethinking Love as Passion: Jeanette Winterson’s The Daylight Gate
Authors: Boucher Geoff M.
Published: December 2021

Jeanette Winterson’s magical realist love stories, such as The Passion, have been read by some critics in terms of a tendency to idealise romance as a transformative passion that transcends social structures. In this article, I propose that Winterson’s recent gothic novel, The Daylight Gate, critically revises a set of Romantic themes first broached in The Passion, exposing and interrogating the fantasy scenario at the centre of romantic love. This narrative about magic and the devil explores the ambivalence of passion as possession—diabolical and contractual—before using this to critique the desire for transcendence implied by “undying love”. Metaphysics becomes a metaphor for metapsychology, where the Romantic motif of undying love as connected to fatal desire is complicated by a traversal of the fantasy of the union of two immortal souls. These revisions have the effect of reversing the implications of Winterson’s earlier treatment of romantic love, turning it back from the personal towards engagement with the political.
Introducing a Novel Experimental Model for Osseo-Disintegration of Titanium Dental Implants Induced by Monobacterial Contamination: An In-Vivo Feasibility Study
Authors: Flörke Christian , Eisenbeiß Anne-Katrin , Metz Ulla , Gülses Aydin , Acil Yahya , Wiltfang Jörg , Naujokat Hendrik
Published: December 2021

Background and Objectives: The aim of the current study was to establish an osseo-disintegration model initiated with a single microorganism in mini-pigs. Materials and Methods: A total of 36 titanium dental implants (3.5 mm in diameter, 9.5 mm in length) was inserted into frontal bone (n: 12) and the basis of the corpus mandible (n: 24). Eighteen implants were contaminated via inoculation of Enterococcus faecalis. Six weeks after implant insertion, bone-to-implant contact (BIC) ratio, interthread bone density (ITBD), and peri-implant bone density (PIBD) were examined. In addition to that, new bone formation was assessed via fluorescence microscopy, histomorphometry, and light microscopical examinations. Results: Compared to the sterile implants, the contaminated implants showed significantly reduced BIC (p < 0.001), ITBD (p < 0.001), and PBD (p < 0.001) values. Around the sterile implants, the green and red fluorophores were overlapping and surrounding the implant without gaps, indicating healthy bone growth on the implant surface, whereas contaminated implants were surrounded by connective tissue. Conclusions: The current experimental model could be a feasible option to realize a significant alteration of dental-implant osseointegration and examine novel surface decontamination techniques without impairing local and systemic inflammatory complications.
SiC Fin-Shaped Gate Trench MOSFET with Integrated Schottky Diode
Authors: Deng Xiaochuan , Liu Rui , Li Songjun , Li Ling , Wu Hao , Li Xuan
Published: December 2021

A silicon carbide (SiC) trench MOSFET featuring fin-shaped gate and integrated Schottky barrier diode under split P type shield (SPS) protection (FS-TMOS) is proposed by finite element modeling. The physical mechanism of FS-TMOS is studied comprehensively in terms of fundamental (blocking, conduction, and dynamic) performance and transient extreme stress reliability. The fin-shaped gate on the sidewall of the trench and integrated Schottky diode at the bottom of trench aim to the reduction of gate charge and improvement on the third quadrant performance, respectively. The SPS region is fully utilized to suppress excessive electric field both at trench oxide and Schottky contact when OFF-state. Compared with conventional trench MOSFET (C-TMOS), the gate charge, Miller charge, Von at third quadrant, Ron,sp·Qgd, and Ron,sp·Qg of FS-TMOS are significantly reduced by 34%, 20%, 65%, 0.1%, and 14%, respectively. Furthermore, short-circuit and avalanche capabilities are discussed, verifying the FS-TMOS is more robust than C-TMOS. It suggests that the proposed FS-TMOS is a promising candidate for next-generation high efficiency and high-power density applications.
Resistance to Sulfuric Acid Corrosion of Geopolymer Concrete Based on Different Binding Materials and Alkali Concentrations
Authors: Yang Wei , Zhu Pinghua , Liu Hui , Wang Xinjie , Ge Wei , Hua Minqi
Published: December 2021

Geopolymer binder is expected to be an optimum alternative to Portland cement due to its excellent engineering properties of high strength, acid corrosion resistance, low permeability, good chemical resistance, and excellent fire resistance. To study the sulfuric acid corrosion resistance of geopolymer concrete (GPC) with different binding materials and concentrations of sodium hydroxide solution (NaOH), metakaolin, high-calcium fly ash, and low-calcium fly ash were chosen as binding materials of GPC for the geopolymerization process. A mixture of sodium silicate solution (Na2SiO3) and NaOH solution with different concentrations (8 M and 12 M) was selected as the alkaline activator with a ratio (Na2SiO3/NaOH) of 1.5. GPC specimens were immersed in the sulfuric acid solution with the pH value of 1 for 6 days and then naturally dried for 1 day until 98 days. The macroscopic properties of GPC were characterized by visual appearance, compressive strength, mass loss, and neutralization depth. The materials were characterized by SEM, XRD, and FTIR. The results indicated that at the immersion time of 28 d, the compressive strength of two types of fly ash-based GPC increased to some extent due to the presence of gypsum, but this phenomenon was not observed in metakaolin-based GPC. After 98 d of immersion, the residual strength of fly ash based GPC was still higher, which reached more than 25 MPa, while the metakaolin-based GPC failed. Furthermore, due to the rigid 3D networks of aluminosilicate in fly ash-based GPC, the mass of all GPC decreased slightly during the immersion period, and then tended to be stable in the later period. On the contrary, in metakaolin-based GPC, the incomplete geopolymerization led to the compressive strength being too low to meet the application of practical engineering. In addition, the compressive strength of GPC activated by 12 M NaOH was higher than the GPC activated by 8 M NaOH, which is owing to the formation of gel depended on the concentration of alkali OH ion, low NaOH concentration weakened chemical reaction, and reduced compressive strength. Additionally, according to the testing results of neutralization depth, the neutralization depth of high-calcium fly ash-based GPC activated by 12 M NaOH suffered acid attack for 98 d was only 6.9 mm, which is the minimum value. Therefore, the best performance was observed in GPC prepared with high-calcium fly ash and 12 M NaOH solution, which is attributed to gypsum crystals that block the pores of the specimen and improve the microstructure of GPC, inhibiting further corrosion of sulfuric acid.
A Flexible Temperature Sensor for Noncontact Human-Machine Interaction
Authors: Chen Shiqi , Han Xiaolong , Hong Peng , Zhang Yue , Yin Xiangyu , He Bingwei
Published: December 2021

Flexible sensors have attracted extensive attention because of their promising applications in the fields of health monitoring, intelligent robots, and electronic skin, etc. During the COVID-19 epidemic, noncontact control of public equipment such as elevators, game consoles, and doors has become particularly important, as it can effectively reduce the risk of cross-infection. In this work, a noncontact flexible temperature sensor is prepared via a simple dip-drying progress, in which poly(3,4-ethylenedioxythiophene):poly(4-styrene sulfonate) (PEDOT:PSS) and printer paper served as the sensing material and the flexible substrate, respectively. We combined the highly sensitive temperature-responsive property of PEDOT:PSS with the good hygroscopicity of printer paper. The prepared sensor shows high sensitivity and good stability in noncontact sensing mode within the temperature range of 20–50 °C. To prove the practicability of the noncontact temperature sensor, a 3 × 2 sensing array is prepared as a noncontact human-machine interface to realize the interaction between player and “Pound-A-Mole game” and a Bluetooth car. These two demos show the sensor′s ability to perceive nearby temperature changes, verifying its application potential as a noncontact human-machine interaction interface.
Application of Nanosilicon to the Sintering of Mg-Mg2Si Interpenetrating Phases Composite
Authors: Olszówka-Myalska Anita , Myalska Hanna , Wrześniowski Patryk , Chrapoński Jacek , Cios Grzegorz
Published: December 2021

The new in situ fabrication process for Mg-Mg2Si composites composed of interpenetrating metal/intermetallic phases via powder metallurgy was characterized. To obtain the designed composite microstructure, variable nanosilicon ((n)Si) (i.e., 2, 4, and 6 vol.% (n)Si) concentrations were mixed with magnesium powders. The mixture was ordered using a sonic method. The powder mixture morphologies were characterized using scanning electron microscopy (SEM), and heating and cooling-induced thermal effects were characterized using differential scanning calorimetry (DSC). Composite sinters were fabricated by hot-pressing the powders under a vacuum of 2.8 Pa. Shifts in the sintering temperature resulted in two observable microstructures: (1) the presence of Mg2Si and MgO intermetallic phases in α-Mg (580 °C); and (2) Mg2Si intermetallic phases in the α-Mg matrix enriched with bands of refined MgO (640 °C). Materials were characterized by light microscopy (LM) with quantitative metallography, X-ray diffraction (XRD), open porosity measurements, hardness testing, microhardness testing, and nanoindentation. The results revealed that (n)Si in applied sintering conditions ensured the formation of globular and very fine Mg2Si particles. The particles bonded with each other to form an intermetallic network. The volume fraction of this network increased with (n)Si concentration but was dependent on sintering temperature. Increasing sintering temperature intensified magnesium vaporization, affecting the composite formation mechanism and increasing the volume fraction of silicide.
Critical Redistribution of Nitrogen in the Austenitic Cr-Mn Steel under Severe Plastic Deformation
Authors: Shabashov Valery , Lyashkov Kirill , Kozlov Kirill , Zavalishin Vladimir , Zamatovskii Andrey , Kataeva Natalya , Sagaradze Victor , Ustyugov Yurii
Published: December 2021

A narrow temperature range of changes in the mechanism and kinetics of structural-phase transformations during mechanical alloying under deformation in rotating Bridgman anvils was determined by the methods of Mössbauer spectroscopy, electron microscopy, and mechanical tests in the high-nitrogen chromium-manganese steel FeMn22Cr18N0.83. The experimentally established temperature region is characterized by a change in the direction of nitrogen redistribution—from an increase in the N content in the metal matrix during cold deformation to a decrease with an increase in the temperature and degree of severe plastic deformation. The change in the direction of nitrogen redistribution is due to the acceleration of the decomposition of a nitrogen-supersaturated solid solution of austenite with the formation of secondary nanocrystalline nitrides. The presence of a transition region for the mechanism of structural-phase transitions is manifested in the abnormal behavior of the mechanical properties of steel.
High Refractive Index Silica-Titania Films Fabricated via the Sol–Gel Method and Dip-Coating Technique—Physical and Chemical Characterization
Authors: Zięba Magdalena , Wojtasik Katarzyna , Tyszkiewicz Cuma , Gondek Ewa , Nizioł Jacek , Suchanek Katarzyna , Wojtasik Michał , Pakieła Wojciech , Karasiński Paweł
Published: December 2021

Crack-free binary SiOx:TiOy composite films with the refractive index of ~1.94 at wavelength 632.8 nm were fabricated on soda-lime glass substrates, using the sol–gel method and dip-coating technique. With the use of transmission spectrophotometry and Tauc method, the energy of the optical band gap of 3.6 eV and 4.0 eV were determined for indirect and direct optical allowed transitions, respectively. Using the reflectance spectrophotometry method, optical homogeneity of SiOx:TiOy composite films was confirmed. The complex refractive index determined by spectroscopic ellipsometry confirmed good transmission properties of the developed SiOx:TiOy films in the Vis-NIR spectral range. The surface morphology of the SiOx:TiOy films by atomic force microscopy (AFM) and scanning electron microscopy (SEM) methods demonstrated their high smoothness, with the root mean square roughness at the level of ~0.15 nm. Fourier-transform infrared (FTIR) spectroscopy and Raman spectroscopy were used to investigate the chemical properties of the SiOx:TiOy material. The developed binary composite films SiOx:TiOy demonstrate good waveguide properties, for which optical losses of 1.1 dB/cm and 2.7 dB/cm were determined, for fundamental TM0 and TE0 modes, respectively.
Spontaneous Polarization Reversal Induced by Proton Exchange in Z-Cut Lithium Niobate α-Phase Channel Waveguides
Authors: Rambu Alicia Petronela , Tiron Vasile , Oniciuc Eugen , Tascu Sorin
Published: December 2021

The α-phase waveguides directly produced in one fabrication step only are well known for preserving both the excellent nonlinear properties and the ferroelectric domains orientation of lithium niobate substrates. However, by using the piezoresponse force microscopy (PFM), we present a coherent study on ferroelectric dipoles switching induced by the fabrication process of α-phase waveguides on Z-cut congruent lithium niobate (CLN) substrates. The obtained results show that the proton exchange process induces a spontaneous polarization reversal and a reduction in the piezoelectric coefficient d33. The quantitative assessments of the impact of proton exchange on the piezoelectric coefficient d33 have been quantified for different fabrication parameters. By coupling systematic PFM investigation and optical characterizations of α-phase protonated regions and virgin CLN on ±Z surfaces of the samples, we find a very good agreement between index contrast (optical investigation) and d33 reduction (PFM investigations). We clearly show that the increase in the in-diffused proton concentration (increase in index contrast) in protonated zones decreases the piezoelectric coefficient d33 values. Furthermore, having a high interest in nonlinear performances of photonics devices based on PPLN substrates, we have also investigated how deep the spontaneous polarization reversal induced by proton exchange takes place inside the α-phase channel waveguides.
Novel Liquid Chitosan-Based Biocoagulant for Treatment Optimization of Fish Processing Wastewater from a Moroccan Plant
Authors: Nouj Nisrine , Hafid Naima , El Alem Noureddine , Cretescu Igor
Published: December 2021

A novel liquid chitosan-based biocoagulant for treating wastewater from a Moroccan fish processing plant was successfully prepared from shrimp shells (Parapenaeus longirostris), the most abundant fish by-products in the country. The shells were characterized using scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, and Fourier transforms infrared spectroscopy. Using chitosan without adding acetic acid helps to minimize its negative impact on the environment. At the same time, the recovery of marine shellfish represents a promising solution for the management of solid fish waste. In order to test the treatment efficiency of the biocoagulant developed, a qualitative characterization of these effluents was carried out beforehand. The optimization process was conducted in two steps: jar-test experiments and modeling of the experimental results. The first step covered the preliminary assessment to identify the most influential operational parameters (experimental conditions), whereas the second step concerned the study of the effects of three significant operational parameters and their interactions using a Box–Behnken experimental design. The variables involved were the concentration of coagulant (X1), the initial pH (X2), and the temperature (X3) of the wastewater samples, while the responses were the removal rates of turbidity (Y1) and BOD5 (Y2). The regression models and response surface contour plots revealed that chitosan as a liquid biocoagulant was effective in removing turbidity (98%) and BOD5 (53%) during the treatment. The optimal experimental conditions were found to be an alkaline media (pH = 10.5) and a biocoagulant dose of 5.5 mL in 0.5 L of fish processing wastewater maintained at 20 °C.
Thin Films of Nanocrystalline Fe(pz)[Pt(CN)4] Deposited by Resonant Matrix-Assisted Pulsed Laser Evaporation
Authors: Maskowicz Dominik , Jendrzejewski Rafał , Kopeć Wioletta , Gazda Maria , Karczewski Jakub , Niedziałkowski Paweł , Kleibert Armin , Vaz Carlos A. F. , Garcia Yann , Sawczak Mirosław
Published: December 2021

Prior studies of the thin film deposition of the metal-organic compound of Fe(pz)Pt[CN]4 (pz = pyrazine) using the matrix-assisted pulsed laser evaporation (MAPLE) method, provided evidence for laser-induced decomposition of the molecular structure resulting in a significant downshift of the spin transition temperature. In this work we report new results obtained with a tunable pulsed laser, adjusted to water resonance absorption band with a maximum at 3080 nm, instead of 1064 nm laser, to overcome limitations related to laser–target interactions. Using this approach, we obtain uniform and functional thin films of Fe(pz)Pt[CN]4 nanoparticles with an average thickness of 135 nm on Si and/or glass substrates. X-ray diffraction measurements show the crystalline structure of the film identical to that of the reference material. The temperature-dependent Raman spectroscopy indicates the spin transition in the temperature range of 275 to 290 K with 15 ± 3 K hysteresis. This result is confirmed by UV-Vis spectroscopy revealing an absorption band shift from 492 to 550 nm related to metal-to-ligand-charge-transfer (MLCT) for high and low spin states, respectively. Spin crossover is also observed with X-ray absorption spectroscopy, but due to soft X-ray-induced excited spin state trapping (SOXIESST) the transition is not complete and shifted towards lower temperatures.
Effect of Temperature on Microstructure and Mechanical Properties of Fe-9Ni-2Cu Steel during the Tempering Process
Authors: Huang Xi , Wang Lianbo , Wang Zemin , Wang Zhanyong , Liu Qingdong
Published: December 2021

In this paper, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray stress meter (XRSA), atom probe tomography (APT), hardness, and tensile tests were used to study the effect of tempering temperature on the microstructure and properties of Fe-9Ni-2Cu steel. The results show that after the quenched samples were tempered at 460 °C for 2 h, the hardness values increased from 373 to 397 HV, and elongation also increased from 13% to 16%. With the tempering temperature increasing from 460 to 660 °C, the hardness firstly decreases from 397 to 353 HV and then increases to 377 HV, while the elongation increases to 17% and then decreases to 11%. The variation of the mechanical properties greatly depends on the evolution of the Cu-rich phase and carbides. The precipitation strengthening of the Cu-rich phase and carbides leads to the increase of hardness, but when the precipitate is coarsened, the precipitation strengthening weakens, and then, the hardness increases. When the tempering temperature is 560 °C, a large amount of stable reverse transformation austenite was formed with a content of 7.1%, while the tensile strength reached the lowest value of 1022 MPa and the elongation reached the maximum value of 17%.
Triboluminescence Phenomenon Based on the Metal Complex Compounds—A Short Review
Authors: Szukalski Adam , Kabanski Adam , Goszyk Julia , Adaszynski Marek , Kaczmarska Milena , Gaida Radoslaw , Wyskiel Michal , Mysliwiec Jaroslaw
Published: December 2021

Triboluminescence (TL) is a phenomenon of light emission resulting from the mechanical force applied to a substance. Although TL has been observed for many ages, the radiation mechanism is still under investigation. One of the exemplary compounds which possesses triboluminescent properties are copper(I) thiocyanate bipyridine triphenylphosphine complex [Cu(NCS)(py)2(PPh3)], europium tetrakis dibenzoylmethide triethylammonium EuD4TEA, tris(bipyridine)ruthenium(II) chloride [Ru(bpy)3]Cl2, and bis(triphenylphosphine oxide)manganese(II) bromide Mn(Ph3PO)2Br2. Due to the effortless synthesis route and distinct photo- and triboluminescent properties, these compounds may be useful model substances for the research on the triboluminescence mechanism. The advance of TL studies may lead to the development of a new group of sensors based on force-responsive (mechanical stimuli) materials. This review constitutes a comprehensive theoretical study containing available information about the coordination of metal complex synthesis methodologies with their physical, chemical, and spectroscopic properties.