bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of Pancreas Transplantation on the Patient Survival—An Analysis of the Japanese Pancreas Transplants Registry
Authors: Ito Taihei , Kenmochi Takashi , Aida Naohiro , Matsushima Hajime , Kurihara Kei , Ishihara Takuma , Shintani Ayumi , Asaoka Tadafumi , Ito Toshinori
Published: July 2020

Background: The impact of pancreas transplantation, including kidney transplantation on patients’ life prognoses, is unclear in Japan. An analysis of the data of the Japan Pancreas Transplant Registry was performed to compare the patient survival between on the waiting list and after pancreas transplantation, and investigate the factors that affect the patient survival after pancreatic transplantation. Methods: The life prognoses of 361 patients who underwent pancreas transplantation from 2000 to December 2018 were examined. Results: The survival rates at 1, 5, and 10 years on the waiting list were 98.4%, 90.3%, and 78.1%, respectively, while those after transplantation were significantly improved (p = 0.029) at 100%, 97.5%, and 88.9%, respectively. Furthermore, the survival rates of patients waiting for simultaneous pancreas and kidney transplantation (SPK) at 1, 5, and 10 years were 98.2%, 89.4%, and 75.4%, respectively, while those after SPK were also significantly improved (p = 0.026) at 100%, 94.6%, and 88.8%. The multivariable analysis revealed that the duration of diabetes before surgery was the only independent risk factor (hazard ratio = 1.095, p = 0.012) that affected the patient survival after SPK. Conclusion: Pancreas transplantation was found to improve the life prognosis of patients with type 1 diabetes, especially those with end-stage renal failure waiting for SPK.
Co-Management as a Successful Strategy for Marine Conservation
Authors: Voorberg William , Van der Veer Reinout
Published: July 2020

Marine Protected Areas (MPAs) are a primary tool for conserving marine biodiversity. The literature presents a scattered picture regarding the extent to which co-management can be considered valuable. In this study we examine, what conditions are for co-management to make a contribution to conserving marine ecosystems (e.g., stopping coral bleaching and safeguarding fish populations). By combining data on MPA management practices with a novel source of global biodata collected by citizens (ReefCheck), we demonstrate that if co-management is part of a formal governmental strategy, coral reefs show up to 86% fewer bleached colonies and up to 12.2 times larger fish populations than co-managed MPAs lacking formalized governmental support.
Marine Biofouling: A European Database for the Marine Renewable Energy Sector
Authors: Vinagre Pedro Almeida , Simas Teresa , Cruz Erica , Pinori Emiliano , Svenson Johan
Published: July 2020

Biofouling is a major problem shared among all maritime sectors employing submerged structures where it leads to substantially increased costs and lowered operational lifespans if poorly addressed. Insight into the ongoing processes at the relevant marine locations is key to effective management of biofouling. Of specific concern for the marine renewable energy (MRE) sector is the fact that information on biofouling composition and magnitude across geographies is dispersed throughout published papers and consulting reports. To enable rapid access to relevant key biofouling events the present work describes a European biofouling database to support the MRE sector and other maritime industries. The database compiles in one document qualitative and quantitative data for challenging biofouling groups, including non-native species associated with MRE and related marine equipment, in different European Ecoregions. It provides information on the occurrence of fouling species and data on key biofouling parameters, such as biofouling thickness and weight. The database aims to aid the MRE sector and offshore industries in understanding which biofouling communities their devices are more susceptible to at a given site, to facilitate informed decisions. In addition, the biofouling mapping is useful for the development of biosecurity risk management plans as well as academic research.
Impact of Improved Mellor–Yamada Turbulence Model on Tropical Cyclone-Induced Vertical Mixing in the Oceanic Boundary Layer
Authors: Kim Taekyun , Moon Jae-Hong
Published: July 2020

It has been identified that there are several limitations in the Mellor–Yamada (MY) turbulence model applied to the atmospheric mixed layer, and Nakanishi and Niino proposed an improved MY model using a database for large-eddy simulations. The improved MY model (Mellor–Yamada–Nakanishi–Niino model; MYNN model) is popular in atmospheric applications; however, it is rarely used in oceanic applications. In this study, the MY model and the MYNN model are compared to identify the efficiency of the MYNN model incorporated into an ocean general circulation model. To investigate the impact of the improved MY model on the vertical mixing in the oceanic boundary layer, the response of the East/Japan Sea to Typhoon Maemi in 2003 was simulated. After the typhoon event, the sea surface temperature obtained from the MYNN model showed better agreement with the satellite measurements than those obtained from the MY model. The MY model produced an extremely shallow mixed layer, and consequently, the surface temperatures were excessively warm. Furthermore, the near-inertial component of the velocity simulated using the MY model was larger than that simulated using the MYNN model at the surface layer. However, in the MYNN model, the near-inertial waves became larger than those simulated by the MY model at all depths except the surface layer. Comparatively, the MYNN model showed enhanced vertical propagation of the near-inertial activity from the mixed layer into the deep ocean, which results in a temperature decrease at the sea surface and a deepening of the mixed layer.
Stereotactic Radiotherapy for Brain Metastases: Imaging Tools and Dosimetric Predictive Factors for Radionecrosis
Authors: Lupattelli Marco , Alì Emanuele , Ingrosso Gianluca , Saldi Simonetta , Fulcheri Christian , Borghesi Simona , Tarducci Roberto , Aristei Cynthia
Published: July 2020

Radionecrosis (RN) is the most important side effect after stereotactic radiotherapy (SRT) for brain metastases, with a reported incidence ranging from 3% to 24%. To date, there are no unanimously accepted criteria for iconographic diagnosis of RN, as well as no definitive dose-constraints correlated with the onset of this late effect. We reviewed the current literature and gave an overview report on imaging options for the diagnosis of RN and on dosimetric parameters correlated with the onset of RN. We performed a PubMed literature search according to the preferred reporting items and meta-analysis (PRISMA) guidelines, and identified articles published within the last ten years, up to 31 December 2019. When analyzing data on diagnostic tools, perfusion magnetic resonance imaging (MRI) seems to be very useful allowing evaluation of the blood flow in the lesion using the relative cerebral blood volume (rCBV) and blood vessel integrity using relative peak weight (rPH). It is necessary to combine morphological with functional imaging in order to match information about lesion morphology, metabolism and blood-flow. Eventually, serial imaging follow-up is needed. Regarding dosimetric parameters, in radiosurgery (SRS) V12 < 8 cm3 and V10 < 10.5 cm3 of normal brain are the most reliable prognostic factors, whereas in hypo-fractionated stereotactic radiotherapy (HSRT) V18 and V21 are considered the main predictive independent risk factors of RN.
Possible Differential Diagnosis of the Degrees of Rheological Disturbances in Patients with Type 2 Diabetes Mellitus by Dielectrophoresis of Erythrocytes
Authors: Kruchinina Margarita V. , Gromov Andrey A. , Generalov Vladimir M. , Kruchinin Vladimir N.
Published: July 2020

Hemorheological disorders in structural and functional parameters of erythrocytes are involved in the pathological process in type 2 diabetes mellitus (DM). Aim: to investigate the feasibility of differential diagnosis of the degrees of rheological disturbances in patients with type 2 DM by dielectrophoresis of erythrocytes. Methods: 62 subjects (58.7 ± 1.6 years) with type 2 DM diagnosed according to the criteria of the ADA were subdivided into two groups: medium (n = 47) and high (n = 15) risk of microcirculatory disturbances (EASD, 2013). Electric and viscoelastic parameters of erythrocytes were determined by dielectrophoresis using an electric optical system of cell detection. Results: the progression of rheological disturbances in the patients with type 2 DM was accompanied by significant decreases in deformation amplitude; dipole moment; polarizability; and membrane capacity; and increases in conductivity, viscosity, rigidity, hemolysis, and formation of aggregates (p < 0.05). Combined use of the parameters increased sensitivity (97.8%) and specificity (86.7%) for diagnosis of rheological disturbances in type 2 DM. Conclusion: the proposed experimental approach possesses low invasiveness, high productivity, shorter duration, vividness of the results. The method allows to evaluate not only local (renal and ocular) but also systemic status of microcirculation using more than 20 parameters of erythrocytes.
Correction: Going Beyond Panaceas: The Diversity of Land Observatory Forms in Africa. Land 2020, 9, 70
Authors: Grislain Quentin , Bourgoin Jeremy , Anseeuw Ward , Burnod Perrine , Hershaw Eva , Diop Djibril
Published: July 2020

The authors wish to make the following corrections to this paper [...]
Endosperm of Angiosperms and Genomic Imprinting
Authors: Kordyum Elizabeth , Mosyakin Sergei
Published: July 2020

Modern ideas about the role of epigenetic systems in the regulation of gene expression allow us to understand the mechanisms of vital activities in plants, such as genomic imprinting. It is important that genomic imprinting is known first and foremost for the endosperm, which not only provides an embryo with necessary nutrients, but also plays a special biological role in the formation of seeds and fruits. Available data on genomic imprinting in the endosperm have been obtained only for the triploid endosperm in model plants, which develops after double fertilization in a Polygonum-type embryo sac, the most common type among angiosperms. Here we provide a brief overview of a wide diversity of embryo sacs and endosperm types and ploidy levels, as well as their distribution in the angiosperm families, positioned according to the Angiosperm Phylogeny Group IV (APG IV) phylogenetic classification. Addition of the new, non-model taxa to study gene imprinting in seed development will extend our knowledge about the epigenetic mechanisms underlying angiosperm fertility.
Deposition of Durable Micro Copper Patterns into Glass by Combining Laser-Induced Backside Wet Etching and Laser-Induced Chemical Liquid Phase Deposition Methods
Authors: Seo Jae Min , Kwon Kui-Kam , Song Ki Young , Chu Chong Nam , Ahn Sung-Hoon
Published: July 2020

Glass is a well-known non-conductive material that has many useful properties, and considerable research has been conducted into making circuits on glass. Many deposition techniques have been studied, and laser-induced chemical liquid phase deposition (LCLD) is a well-known and cost-effective method for rapid prototyping of copper deposition on glass. However, the deposition results from the LCLD method on the surface of glass, which shows an issue in its detachment from the substrates because of the relatively low adhesion between deposited copper and the nontreated glass surface. This problem undermines the usability of deposited glass in industrial applications. In this study, the laser-induced backside wet etching (LIBWE) method was performed as a preceding process to fabricate microchannels, which were filled with copper by LCLD. Additional durable copper wire was produced as a result of the enhanced adhesion between the glass and the deposited copper. The adhesion was enhanced by a rough surface and metal layer, which are characteristics of LIBWE machining. Furthermore, the proposed method is expected to broaden the use of deposited glass in industrial applications, such as in stacked or covered multilayer structures with built-in copper wires, because the inserted copper can be physically protected by the microstructures.
Optical Dielectric Loss as a Novel Approach to Specify the Types of Electron Transition: XRD and UV-vis as a Non-Destructive Techniques for Structural and Optical Characterization of PEO Based Nanocomposites
Authors: Muhammed Dana S. , Brza Mohamad A. , M. Nofal Muaffaq , B. Aziz Shujahadeen , A. Hussen Sarkawt , Abdulwahid Rebar T.
Published: July 2020

The structure and optical properties of polyethylene oxide (PEO) doped with tin titanate (SnTiO3) nano-filler were studied by X-ray diffraction (XRD) and UV-Vis spectroscopy as non-destructive techniques. PEO-based composed polymer electrolytes inserted with SnTiO3 nano-particles (NPs) were synthesized through the solution cast technique. The change from crystalline phase to amorphous phase of the host polymer was established by the lowering of the intensity and broadening of the crystalline peaks. The optical constants of PEO/SnTiO3 nano-composite (NC), such as, refractive index (n), optical absorption coefficient (α), dielectric loss (εi), as well as dielectric constant (εr) were determined for pure PEO and PEO/SnTiO3 NC. From these findings, the value of n of PEO altered from 2.13 to 2.47 upon the addition of 4 wt.% SnTiO3NPs. The value of εr also increased from 4.5 to 6.3, with addition of 4 wt.% SnTiO3. The fundamental optical absorption edge of the PEO shifted toward lower photon energy upon the addition of the SnTiO3 NPs, confirming a decrement in the optical band gap energy of PEO. The band gap shifted from 4.78 eV to 4.612 eV for PEO-doped with 4 wt.% SnTiO3. The nature of electronic transitions in the pure and the composite material were studied on the basis of Tauc’s model, while optical εi examination was also carried out to calculate the optical band gap.
Prediction and Optimization of Surface Roughness in a Turning Process Using the ANFIS-QPSO Method
Authors: Alajmi Mahdi S. , Almeshal Abdullah M.
Published: July 2020

This study presents a prediction method of surface roughness values for dry and cryogenic turning of AISI 304 stainless steel using the ANFIS-QPSO machine learning approach. ANFIS-QPSO combines the strengths of artificial neural networks, fuzzy systems and evolutionary optimization in terms of accuracy, robustness and fast convergence towards global optima. Simulations revealed that ANFIS-QPSO results in accurate prediction of surface roughness with RMSE = 4.86%, MAPE = 4.95% and R2 = 0.984 for the dry turning process. Similarly, for the cryogenic turning process, ANFIS-QPSO resulted in surface roughness predictions with RMSE = 5.08%, MAPE = 5.15% and R2 = 0.988 that are of high agreement with the measured values. Performance comparisons between ANFIS-QPSO, ANFIS, ANFIS-GA and ANFIS-PSO suggest that ANFIS-QPSO is an effective method that can ensure a high prediction accuracy of surface roughness values for dry and cryogenic turning processes.
The Recognition of the Micro-Events in Cement Composites and the Identification of the Destruction Process Using Acoustic Emission and Sound Spectrum
Authors: Logoń Dominik , Schabowicz Krzysztof
Published: July 2020

This paper presents the recognition of micro-events and their concentration in quasi-brittle cement composites and the identification of the destruction process based on acoustic emission and sound spectrum. The tests were conducted on a quasi-brittle composite of a cement paste reinforced with a high volume of dispersed polypropylene fibers. The possibility of identifying the destruction process based on acoustic emission and sound spectrum was confirmed. This paper focused on the identification of micro-events using the 3D spectrum. It was shown that the identification of the concentration of micro-events precedes the occurrence of critical crack fcr, ending the Hooke’s law range. The ability to recognize this phenomenon with the use of the 3D spectrum makes it possible to predict the structure destruction process and subsequently to assess the structure destruction (micro and macro-cracks) and the reinforcement destruction (pull-off, breaking). It was confirmed that the three-dimensional spectrum provided additional information, enabling a better recognition of micro and macro-changes in the structure of the samples based on the analysis of sound intensity, amplitudes, and frequencies.
Enzymatic Hydrolysis of Poly(3-Hydroxybutyrate-co-3-Hydroxyvalerate) Scaffolds
Authors: Kovalcik Adriana , Obruca Stanislav , Kalina Michal , Machovsky Michal , Enev Vojtech , Jakesova Michaela , Sobkova Marketa , Marova Ivana
Published: July 2020

Polyhydroxyalkanoates (PHAs) are hydrolyzable bio-polyesters. The possibility of utilizing lignocellulosic waste by-products and grape pomace as carbon sources for PHA biosynthesis was investigated. PHAs were biosynthesized by employing Cupriavidus necator grown on fructose (PHBV-1) or grape sugar extract (PHBV-2). Fifty grams of lyophilized grape sugar extract contained 19.2 g of glucose, 19.1 g of fructose, 2.7 g of pectin, 0.52 g of polyphenols, 0.51 g of flavonoids and 7.97 g of non-identified rest compounds. The grape sugar extract supported the higher production of biomass and modified the composition of PHBV-2. The biosynthesized PHAs served as matrices for the preparation of the scaffolds. The PHBV-2 scaffolds had about 44.2% lower crystallinity compared to the PHBV-1 scaffolds. The degree of crystallinity markedly influenced the mechanical behavior and enzymatic hydrolysis of the PHA scaffolds in the synthetic gastric juice and phosphate buffer saline solution with the lipase for 81 days. The higher proportion of amorphous moieties in PHBV-2 accelerated enzymatic hydrolysis. After 81-days of lasting enzymatic hydrolysis, the morphological changes of the PHBV-1 scaffolds were negligible compared to the visible destruction of the PHBV-2 scaffolds. These results indicated that the presence of pectin and phenolic moieties in PHBV may markedly change the semi-crystalline character of PHBV, as well as its mechanical properties and the course of abiotic or enzymatic hydrolysis.
Modelling Inhomogeneity of Veneer Laminates with a Finite Element Mapping Method Based on Arbitrary Grayscale Images
Authors: Zerbst David , Liebold Christian , Gereke Thomas , Haufe André , Clauß Sebastian , Cherif Chokri
Published: July 2020

Failure and deformation behavior of veneer laminates of ring porous wood species vary with the individual arrangement of early- and latewood zones over a veneer sheet. Therefore, a method is presented, where local failure and damage modes are considered for finite element models with respect to forming simulations, during the development process of automotive interior trim parts. Within the mapping tool Envyo, a routine has been realized for the discretization of early- and latewood zones from ash wood veneer surfaces to finite element meshes. The routine performs the following steps: reading a grayscale image of known size and generation of a point cloud based on the number of pixels; transformation and scaling of the generated point cloud to align with a target finite element mesh; nearest neighbor search and transfer of grayscale values to the target mesh element centroids; assigning part and therefore material properties to the target elements based on the mapped grayscale value and user-defined grayscale ranges. Due to the absence of measurement data for early- and latewood, optimization was used to identify locally varying material constants. A set of material input parameters for early- and latewood was created, calibrating the force-displacement response of tensile test simulations to corresponding experimental curves. The numerical results gave a very good agreement to the failure behavior of tensile tests in the loading directions longitudinal and transverse to the fiber orientation. Furthermore, in a stochastic analysis the characteristic distribution of tensile strength and ultimate strain could be verified for the suggested procedure. The introduced modelling approach can be applied for the discrete implementation of inhomogeneity to numerical simulations.
Synthesis and Characterization of Low-Cost Cresol-Based Benzoxazine Resins as Potential Binders in Abrasive Composites
Authors: Jamrozik Artur , Barczewski Mateusz , Framski Grzegorz , Baranowski Daniel , Jakubowska Paulina , Klapiszewski Łukasz , Jesionowski Teofil , Voelkel Adam , Strzemiecka Beata
Published: July 2020

A series of cresol-based benzoxazines were synthesized for potential application as a polymer matrix in abrasive composites. The chemical structures of the obtained benzoxazine resins were investigated in detail using Fourier transform infrared spectroscopy (FTIR) and hydrogen-1 as well as carbon-13 nuclear magnetic resonance spectroscopy (1H NMR, 13C NMR) with an additional analysis using two-dimensional NMR techniques (2D NMR 1H-1H COSY, 1H-13C gHSQC and gHMBC). Structural analysis confirmed the presence of vibrations of -O-C-N- at ~950 cm−1 wavenumber, characteristic for an oxazine ring. The thermal properties of benzoxazine monomers were examined using differential scanning calorimetry (DSC) analysis. The polymerization enthalpy varied from 143.2 J/g to 287.8 J/g. Thermal stability of cresol-based benzoxazines was determined using thermogravimetry (TGA) analysis with additional analysis of the amount of volatile organic compounds (VOC) emitted from the synthesized benzoxazines during their crosslinking by static headspace coupled with gas chromatography technique (HS-GC). The amount of residual mass significantly differed between all synthesized polybenzoxazines in the range from 8.4% to 21.2%. The total VOC emission for benzoxazines decreased by 46–77% in reference to a conventional phenolic binder. The efficiency of abrasive composites with the benzoxazine matrix was evaluated based on abrasion tests. Performed analyses confirmed successful synthesis and proper chemical structure of cresol-based benzoxazines. All the experiments indicated that benzoxazines based on different cresol isomers significantly differ from each other. Good thermal performance and stability of the abrasive composites with the polybenzoxazine matrix and significantly lower VOC emission allow us to state that benzoxazines can be a promising and valuable alternative to the phenolics and a new path for the development of modern, eco-friendly abrasives.
Nitridated Ca2NaMg2V3O12: Eu3+ Vanadate Garnet Phosphor-in-Glass
Authors: Pasinski Damian , Sokolnicki Jerzy
Published: July 2020

In this study, Ca2NaMg2V3O12 coordination compound undoped and doped with Eu3+ obtained in the air and ammonia atmosphere by solid-state reaction was investigated. Ca2NaMg2V3O12: Eu3+ obtained in the ammonia atmosphere was then investigated as a phosphor-in-glass (PiG). Annealed Ca2NaMg2V3O12: Eu3+ phosphor forms a single phase with the cubic garnet structure and Ia3d space group. Nitridation in ammonia causes a widening of a VO43− group emission band on the low energy side and it red-shifts by 20 nm. The emission of Eu3+ is extended as compared to the non-nitridated phosphor. Ca2NaMg2V3O12: Eu3+ after nitridation shows higher emission quantum yield (QY): 49 vs. 45 and lower correlated color temperature (CCT) and 4179 vs. 4998 as compared to phosphor without nitridation. The QY for PiG is 55. The thermal stability of nitridated phosphors is superior to phosphor obtained in the air atmosphere and is further enhanced for PiG.
Interlaminar Shear Strength and Failure Analysis of Aluminium-Carbon Laminates with a Glass Fiber Interlayer after Moisture Absorption
Authors: Bieniaś Jarosław , Jakubczak Patryk , Droździel Magda , Surowska Barbara
Published: July 2020

This article presents selected aspects of an interlaminar shear strength and failure analysis of hybrid fiber metal laminates (FMLs) consisting of alternating layers of a 2024-T3 aluminium alloy and carbon fiber reinforced polymer. Particular attention is paid to the properties of the hybrid FMLs with an additional interlayer of glass composite at the metal-composite interface. The influence of hygrothermal conditioning, the interlaminar shear strength (short beam shear test), and the failure mode were investigated and discussed. It was found that fiber metal laminates can be classified as a material with significantly less adsorption than in the case of conventional composites. Introducing an additional layer of glass composite at the metal-composite interface and hygrothermal conditioning influence the decrease in the interlaminar shear strength. The major forms of damage to the laminates are delaminations in the layer of the carbon composite, at the metal-composite interface, and delaminations between the layers of glass and carbon composites.
High Temperature Mechanical Properties of a Vented Ti-6Al-4V Honeycomb Sandwich Panel
Authors: Shang Lei , Wu Ye , Fang Yuchao , Li Yao
Published: July 2020

For aerospace applications, honeycomb sandwich panels may have small perforations on the cell walls of the honeycomb core to equilibrate the internal core pressure with external gas pressure, which prevent face-sheet/core debonding due to pressure build-up at high temperature. We propose a new form of perforation on the cell walls of honeycomb sandwich panels to reduce the influence of the perforations on the cell walls on the mechanical properties. In this paper, the high temperature mechanical properties of a new vented Ti-6Al-4V honeycomb sandwich panel were investigated. A vented Ti-6AL-4V honeycomb sandwich panel with 35Ti-35Zr-15Cu-15Ni as the filler alloy was manufactured by high-temperature brazing. The element distribution of the brazed joints was examined by means of SEM (scanning electron microscopy) and EDS (energy-dispersive spectroscopy) analyses. Compared to the interaction between the face-sheets and the brazing filler, the diffusion and reaction between the honeycomb core and the brazing filler were stronger. The flatwise compression and flexural mechanical properties of the vented honeycomb sandwich panels were investigated at 20, 160, 300, and 440 °C, respectively. The flatwise compression strength, elastic modulus, and the flexural strength of the vented honeycomb sandwich panels decreased with the increase of temperature. Moreover, the flexural strength of the L-direction sandwich panels was larger than that of the W-direction sandwich panels at the same temperature. More importantly, the vented honeycomb sandwich panels exhibited good compression performance similar to the unvented honeycomb sandwich panels, and the open holes on the cell walls have no negative effect on the compression performance of the honeycomb sandwich panels in these conditions. The damage morphology observed by SEM revealed that the face-sheets and the brazing zone show ductile and brittle fracture behaviors, respectively.
Ultra-High Molecular Weight Polyethylene/Titanium-Hybrid Implant for Bone-Defect Replacement
Authors: Maksimkin Aleksey V. , Senatov Fedor S. , Niaza Kirill , Dayyoub Tarek , Kaloshkin Sergey D.
Published: July 2020

A hybrid implant with a structure mimicking that of natural bone was developed. Titanium alloy Ti–6Al–4V prepared with three-dimensional (3D)-printing technology was used to simulate the cortical-bone layer. The mismatch in the mechanical properties of bone and titanium alloy was solved by creating special perforations in the titanium’s surface. Porous ultra-high molecular weight polyethylene (UHMWPE) with high osteogenous properties was used to simulate the cancellous-bone tissue. A method for creating a porous UHMWPE structure inside the titanium reinforcement is proposed. The porous UHMWPE was studied with scanning electron microscope (SEM) to confirm that the pores that formed were open, interconnected, and between 50 and 850 μm in size. Mechanical-compression tests done on the obtained UHMWPE/titanium-hybrid-implant samples showed that their mechanical properties simulated those of natural bone.
Assessment and Characterization of Some New Photosensitizers for Antimicrobial Photodynamic Therapy (aPDT)
Authors: Dascalu (Rusu) Laura Monica , Moldovan Marioara , Prodan Doina , Ciotlaus Irina , Popescu Violeta , Baldea Ioana , Carpa Rahela , Sava Sorina , Chifor Radu , Badea Mindra Eugenia
Published: July 2020

The novelty of this study consists on the formulation and evaluation of five complex experimental natural photosensitizers (PS): gel with oregano essential oil (O), gel with methylene blue (AM), gel with a mixture of essential oils (Thieves-H), gel with arnica oil and curcuma extract (CU) and gel with frankincense essential oil (T), used as photosensitizing agents (PS) in antimicrobial photodynamic therapy (aPDT) in the control of microbial biofilm in oral cavity. The experimental PS were characterized by gas chromatography-mass spectrometry (GC-MS), Fourier-transform infrared spectroscopy (FTIR), UV-Vis spectroscopy, cytotoxicity assay, antimicrobial effect and scanning electron microscopy (SEM). The IR spectra of the experimental PS with essential oils exhibit absorption bands due to the presence of water and glycerol in high quantities. The studied compounds had a reduced cytotoxic effect on cell cultures. The lowest cytotoxic effect was observed in experimental PS with oregano essential oil and methylene blue PS. Essential oils with proven antibacterial capabilities used in experimental PS confer antibacterial activity to the gels in which they are incorporated, an activity that may be more efficient use of a PDT therapy. Single bacteria were detected mainly by SEM after 12 h, while aggregate bacteria and micro colonies dominated the samples at 48 h.
The Luminescence of 1,8-Diazafluoren-9-One/Titanium Dioxide Composite Thin Films for Optical Application
Authors: Lewkowicz Aneta , Bogdanowicz Robert , Bojarski Piotr , Pierpaoli Mattia , Gryczyński Ignacy , Synak Anna , Mońka Michał , Karczewski Jakub , Struck-Lewicka Wiktoria , Wawrzyniak Renata , Markuszewski Michał J.
Published: July 2020

The investigation of innovative label-free α-amino acids detection methods represents a crucial step for the early diagnosis of several diseases. While 1,8-diazafluoren-9-one (DFO) is known in forensic application because of the fluorescent products by reacting with the amino acids present in the papillary exudate, its application for diagnostic purposes has not been fully investigated. The stabilization of DFO over a transparent substrate allows its complexation with biomolecules for the detection of α-amino acids. In this study, DFO was immobilized into a titanium dioxide (TiO2) matrix for the fluorescence detection of glycine, as a target α-amino acid (a potential marker of the urogenital tract cancers). The DFO/TiO2 composite was characterized by atomic force microscopy, spectroscopic ellipsometry, fluorescence spectroscopy and fluorescence microscopy. The performed fluorescent studies indicate spectacular formation of aggregates at higher concentration. The measurements performed using various fluorescence and microscopic techniques together with the suitable analysis show that the aggregates are able to emit short-lived fluorescence.
The Effects of Micro-Segregation on Isothermal Transformed Nano Bainitic Microstructure and Mechanical Properties in Laser Cladded Coatings
Authors: Guo Yanbing , Li Zhuguo , Li Liqun , Feng Kai
Published: July 2020

The design of metastable retained austenite is the key issue to obtain nano bainitic steel with high strength and toughness. In this study, nanostructured Fe-based bainitic coatings were fabricated using laser cladding and following isothermal heat treatment. The microstructures and mechanical properties of the laser cladded coating were investigated. The results show that the Mn, Cr, Co, and Al segregated at the solidified prior grain boundaries. The micro-segregation of the solutes strongly influenced the stability of the austenite. As the isothermal temperature decreases, the interface of the bainite and blocky retained austenite approach to the prior interdendritic regions with the decreasing isothermal temperature, and the final volume fraction also decreases. The volume fractions of each phase and microstructure morphology of the coatings were determined by the interdendritic micro-segregation and isothermal temperatures. The stability of the blocky retained austenite distributed at the interdendritic area was lower than that of film and island-like morphology. This phenomenon contributed to the ductile and tough nano bainitic coatings with tunable mechanical properties.
Effects of a New Type of Shrinkage-Reducing Agent on Concrete Properties
Authors: Masanaga Mari , Hirata Tsuyoshi , Kawakami Hirokatsu , Morinaga Yuka , Nawa Toyoharu , Elakneswaran Yogarajah
Published: July 2020

Shrinkage-reducing agents have been developed to mitigate shrinkage and to control cracks in concrete. This study aims to evaluate the impact of a newly developed shrinkage-reducing agent (N-SRA) on concrete properties and to compare its properties with a conventional shrinkage-reducing agent (C-SRA). The hydration rate, compressive strength, splitting tensile strength, shrinkage, occurrence of cracking, and freezing and thawing were investigated. N-SRA showed higher surface tension than C-SRA and reduced shrinkage to the same degree as C-SRA with half the dosage of C-SRA. The addition of N-SRA or C-SRA did not influence the early compressive strength but slightly reduced splitting tensile strength at seven days. Concrete with N-SRA showed higher compressive strength at 28 days than those of concrete with C-SRA or without SRA. Furthermore, concrete with N-SRA extended the period for the occurrence of shrinkage cracking under restrained conditions. It was found that N-SRA provided excellent freezing and thawing resistance because of the formation of good air voids, while C-SRA demonstrated inefficient behaviour in such an environment.
Carbonyl-Terminated Quinoidal Oligothiophenes as p-Type Organic Semiconductors
Authors: Asoh Takato , Kawabata Kohsuke , Takimiya Kazuo
Published: July 2020

A series of quinoidal oligothiophenes terminated with carbonyl groups (nTDs, n = 2–4) are studied as p-type organic semiconductors for the active materials in organic field-effect transistors (OFETs) both by the theoretical and experimental approaches. The theoretical calculations clearly show their high-lying highest occupied molecular orbital (HOMO) energy levels (EHOMOs), small reorganization energies for hole transport (λholes), and large contribution of sulfur atoms to HOMOs, all of which are desirable for p-type organic semiconductors. Thus, we synthesized nTDs from the corresponding aromatic oligothiophene precursors and then evaluated their physicochemical properties and structural properties. These experimental evaluations of nTDs nicely proved the theoretical predictions, and the largest 4TDs in the series (4,4′′′-dihexyl- and 3′,4,4″,4′′′-tetrahexyl-5H,5′′′H-[2,2′:5′,2″:5″,2′′′-quaterthiophene]-5,5′′′-dione) can afford solution-processed OFETs showing unipolar p-type behaviors and hole mobility as high as 0.026 cm2 V−1 s−1.
Cross-Linked Polythiomethacrylate Esters Based on Naphthalene—Synthesis, Properties and Reprocessing
Authors: Fila Karolina , Podkościelna Beata , Podgórski Maciej
Published: July 2020

Two structurally different aromatic dithioesters were synthesized from two dithiols and methacryloyl chloride. The polymer networks based on methyl methacrylate and/or styrene and the new dimethacrylates were subsequently prepared. The polymerization yields of copolymers were in the range of 95–99%. The thermal and mechanical properties of the copolymers were determined by means of differential scanning calorimetry (DSC), thermogravimetric analysis (TG/DTG), and Shore D hardness. The addition of dithioesters—1,5-NAF-S-Met (or 1,4(1,5)-NAF-CH2S-Met) (from 0.5% to 5%) to MMA- or ST-based polymers results in lowering the glass transition temperature (Tg) by about 8 °C. The thioester-containing polymers based on MMA exhibit lower thermal stability than those with ST. The polythioesters are stable up to 250 °C. The UV/vis spectra and refractive indexes of prepared liquid compositions were also measured. The 1,5-NAF-S-Met (and 1,4(1,5)-NAF-CH2S-Met) improved the refractive index values of ST and MMA compositions. The double bond conversion was also determined for all synthesized materials. The swelling studies of polymers with 20% addition of thioester crosslinkers were investigated. For all polymeric materials with 20% addition of thioesters, depolymerization of the network was carried out by thiol-thioester exchange. The depolymerization products were re-reacted in a thiol-ene reaction with 2-hydroxyethyl methacrylate by thermal initiation. The thiol-ene procedure enabled reprocessing of starting polymers and obtaining new materials characterized by distinctly different thermal, mechanical, and swelling properties. The thiol-ene materials exhibit a lower Shore hardness in the range of 20–50 °Sh, as well as decreased Tg values when compared to starting copolymers. Due to these possible exchange reactions, one can facilely manipulate the properties of the polymers which could lead to the manufacturing of the new products with the desired features. Degradation of the cross-linked structure and recycling of copolymers were also discussed.
Potential of Mineral Fraction in Compost-Like-Output, Methods of Its Obtaining and the Possibility of Using It in the Context of Circular Economy
Authors: Połomka Jacek , Jędrczak Andrzej
Published: July 2020

Most of the systems for the mechanical and biological treatment of waste used in Poland send the 0–80 mm fraction separated from the municipal waste stream, after biostabilization, entirely to a landfill. Such action is not in line with the adopted EU strategy focused on waste management in the circular cycle. The purpose of this work was to assess the technical feasibility of recovering the mineral fractions contained in compost-like-output (CLO) on the proprietary technological line designed for glass recovery. The research was launched in January 2019, and lasted for a subsequent 12 months. In the article, the amounts of mineral fractions possible to be separated from CLO are presented, as well as their morphological composition and selected properties being determined. The processing of CLO on the line allowed to recover on average 69.4 ± 7.0% of the glass. This product was accepted by glass recycling plants. Mineral fractions constituting waste from the glass separation process were tested for their use in winter road maintenance. Tests were also carried out confirming the possibility of using selected mineral fractions (0–10 mm) from CLO to obtain a waste cement mix useful for constructing road foundations using a standard amount of cement.
Enhancement of Gas Barrier Properties of Graphene Oxide/Poly (Lactic Acid) Films Using a Solvent-free Method
Authors: Li Fenfen , Zhang Caili , Weng Yunxuan , Diao Xiaoqian , Zhou Yingxin , Song Xinyu
Published: July 2020

Graphene oxide(GO)/polylactic acid (PLA) nanocomposite, prepared using a solvent-free melt mixing processing, is investigated as a potential oxygen barrier packaging film in this work. In order to disperse GO homogeneously in PLA matrix, hydrophobic silane coupling agent, i.e., γ-(2,3-epoxypropoxy)propyltrimethoxysilane (KH560), is used to modify the graphene oxide sheets. The modified GO is able to be well bonded to the PLA due to the formation of covalent bonds between the epoxy groups of KH560 and the carboxyl and hydroxyl terminal groups of PLA. Furthermore, the thermal stability of GO is enhanced due to the long alkyl side chain of KH560, which could also increase the crystallinity of PLA. As a result, the crystallinity of PLA is significantly improved because of the linear KH560 chains, which can act as nucleating agents to improve the crystallization. The KH560-GO helps to reduce the O2 permeability of KH560-GO/PLA composite films via a dual-action mechanism: (1) providing physical barrier due to their native barrier properties, and (2) by resulting in higher degree of crystallinity. The as-prepared KH560-GO0.75/PLA is able to exhibit ca. 33% and ca. 13% decrease in the PO2 than the neat PLA and GO0.75/PLA film, respectively. Finally, the mechanical properties and impact fractured surfaces indicate that the increase in the tensile strength and elongation at break value of KH560-GO/PLA are due to the strong interfacial adhesion and the strong bonding between the epoxy group of KH560-GO and hydroxyl and carboxyl acid terminal groups of PLA matrix.
Study on the Self-Organization of an Fe-Mn-C-B Coating during Friction with Surface-Active Lubricant
Authors: Barszcz Marcin , Pashechko Mykhaylo , Dziedzic Krzysztof , Jozwik Jerzy
Published: July 2020

This paper investigates the friction process between an Fe-based coating and C45 steel with surface-active lubrication, as well as examines the coating surface before and after tribological testing. As a result, it is possible to determine whether the surface undergoes self-organization during friction. Coatings were produced by hardfacing a subeutectic alloy Fe-Mn-C-B modified by silicon, nickel, chromium and copper. Tribological tests were performed using a pin-on-disc tribometer. The pin (coating) and the disc made of steel C45 were subjected to heat treatment (hardening and tempering). The tests were carried out under loads of 3 MPa, 7 MPa and 10 MPa at a constant sliding velocity of 0.4 m/s and a sliding distance of 5700 m using a surface-active lubricant (glycerine oil). Obtained results were compared with the published results of previous tests carried out under the same conditions but under a load of 20 MPa. Obtained microscopic and spectroscopic results demonstrate that that the friction pair materials (the coating made of subeutectic alloy Fe-Mn-C-B modified by Si, Ni, Cr, Cu and C45 steel) and the surface-active lubricant cause self-organization during friction. The friction surface of the coatings has a flay-laminar structure and is covered with triboreaction products. The surface shows the presence of wear-resistant compounds such as oxides, carbides, borides and nitrides.
Design and Comparative Analysis of New Personalized Recommender Algorithms with Specific Features for Large Scale Datasets
Authors: Bhaskaran S. , Marappan Raja , Santhi B.
Published: July 2020

Nowadays, because of the tremendous amount of information that humans and machines produce every day, it has become increasingly hard to choose the more relevant content across a broad range of choices. This research focuses on the design of two different intelligent optimization methods using Artificial Intelligence and Machine Learning for real-life applications that are used to improve the process of generation of recommenders. In the first method, the modified cluster based intelligent collaborative filtering is applied with the sequential clustering that operates on the values of dataset, user′s neighborhood set, and the size of the recommendation list. This strategy splits the given data set into different subsets or clusters and the recommendation list is extracted from each group for constructing the better recommendation list. In the second method, the specific features-based customized recommender that works in the training and recommendation steps by applying the split and conquer strategy on the problem datasets, which are clustered into a minimum number of clusters and the better recommendation list, is created among all the clusters. This strategy automatically tunes the tuning parameter λ that serves the role of supervised learning in generating the better recommendation list for the large datasets. The quality of the proposed recommenders for some of the large scale datasets is improved compared to some of the well-known existing methods. The proposed methods work well when λ = 0.5 with the size of the recommendation list, |L| = 30 and the size of the neighborhood, |S| < 30. For a large value of |S|, the significant difference of the root mean square error becomes smaller in the proposed methods. For large scale datasets, simulation of the proposed methods when varying the user sizes and when the user size exceeds 500, the experimental results show that better values of the metrics are obtained and the proposed method 2 performs better than proposed method 1. The significant differences are obtained in these methods because the structure of computation of the methods depends on the number of user attributes, λ, the number of bipartite graph edges, and |L|. The better values of the (Precision, Recall) metrics obtained with size as 3000 for the large scale Book-Crossing dataset in the proposed methods are (0.0004, 0.0042) and (0.0004, 0.0046) respectively. The average computational time of the proposed methods takes <10 seconds for the large scale datasets and yields better performance compared to the well-known existing methods.
Projection Methods for Uniformly Convex Expandable Sets
Authors: Chrétien Stéphane , Bondon Pascal
Published: July 2020

Many problems in medical image reconstruction and machine learning can be formulated as nonconvex set theoretic feasibility problems. Among efficient methods that can be put to work in practice, successive projection algorithms have received a lot of attention in the case of convex constraint sets. In the present work, we provide a theoretical study of a general projection method in the case where the constraint sets are nonconvex and satisfy some other structural properties. We apply our algorithm to image recovery in magnetic resonance imaging (MRI) and to a signal denoising in the spirit of Cadzow’s method.
Antagonistic One-To-N Stochastic Duel Game
Authors: Kim Song-Kyoo (Amang)
Published: July 2020

This paper is dealing with a multiple person game model under the antagonistic duel type setup. The unique multiple person duel game with the one-shooting-to-kill-all condition is analytically solved and the explicit formulas are obtained to determine the time dependent duel game model by using the first exceed theory. The model could be directly applied into real-world situations and an analogue of the theory in the paper is designed for solving the best shooting time for hitting all other players at once which optimizes the payoff function under random time conditions. It also mathematically explains to build the marketing strategies for the entry timing for both blue and red ocean markets.