bluuebunny/crossref_metadata_2025 huggingface dataset:
Glioma Cells Acquire Stem-like Characters by Extrinsic Ribosome Stimuli
Authors: Shirakawa Yuki , Ohta Kunimasa , Miyake Shunsuke , Kanemaru Ayumi , Kuwano Akari , Yonemaru Kou , Uchino Shota , Yamaoka Michiko , Ito Yuki , Ito Naofumi , Hide Takuichiro , Shinojima Naoki , Mukasa Akitake , Saito Hideyuki , Jono Hirofumi
Published: November 2021

Although glioblastoma (GBM) stem-like cells (GSCs), which retain chemo-radio resistance and recurrence, are key prognostic factors in GBM patients, the molecular mechanisms of GSC development are largely unknown. Recently, several studies revealed that extrinsic ribosome incorporation into somatic cells resulted in stem cell properties and served as a key trigger and factor for the cell reprogramming process. In this study, we aimed to investigate the mechanisms underlying GSCs development by focusing on extrinsic ribosome incorporation into GBM cells. Ribosome-induced cancer cell spheroid (RICCS) formation was significantly upregulated by ribosome incorporation. RICCS showed the stem-like cell characters (number of cell spheroid, stem cell markers, and ability for trans differentiation towards adipocytes and osteocytes). In RICCS, the phosphorylation and protein expression of ribosomal protein S6 (RPS6), an intrinsic ribosomal protein, and STAT3 phosphorylation were upregulated, and involved in the regulation of cell spheroid formation. Consistent with those results, glioma-derived extrinsic ribosome also promoted GBM-RICCS formation through intrinsic RPS6 phosphorylation. Moreover, in glioma patients, RPS6 phosphorylation was dominantly observed in high-grade glioma tissues, and predominantly upregulated in GSCs niches, such as the perinecrosis niche and perivascular niche. Those results indicate the potential biological and clinical significance of extrinsic ribosomal proteins in GSC development.
Macroscopic, Histologic, and Immunomodulatory Response of Limb Wounds Following Intravenous Allogeneic Cord Blood-Derived Multipotent Mesenchymal Stromal Cell Therapy in Horses
Authors: Mund Suzanne J. K. , MacPhee Daniel J. , Campbell John , Honaramooz Ali , Wobeser Bruce , Barber Spencer M.
Published: November 2021

Limb wounds are common in horses and often develop complications. Intravenous multipotent mesenchymal stromal cell (MSC) therapy is promising but has risks associated with intravenous administration and unknown potential to improve cutaneous wound healing. The objectives were to determine the clinical safety of administering large numbers of allogeneic cord blood-derived MSCs intravenously, and if therapy causes clinically adverse reactions, accelerates wound closure, improves histologic healing, and alters mRNA expression of common wound cytokines. Wounds were created on the metacarpus of 12 horses. Treatment horses were administered 1.51–2.46 × 108 cells suspended in 50% HypoThermosol FRS, and control horses were administered 50% HypoThermosol FRS alone. Epithelialization, contraction, and wound closure rates were determined using planimetric analysis. Wounds were biopsied and evaluated for histologic healing characteristics and cytokine mRNA expression. Days until wound closure was also determined. The results indicate that 3/6 of treatment horses and 1/6 of control horses experienced minor transient reactions. Treatment did not accelerate wound closure or improve histologic healing. Treatment decreased wound size and decreased all measured cytokines except transforming growth factor-β3. MSC intravenous therapy has the potential to decrease limb wound size; however, further work is needed to understand the clinical relevance of adverse reactions.
Harnessing CD8+CD28− Regulatory T Cells as a Tool to Treat Autoimmune Disease
Authors: Ceeraz Sabrina , Thompson Charlotte R. , Beatson Richard , Choy Ernest H.
Published: November 2021

T regulatory cell therapy presents a novel therapeutic strategy for patients with autoimmune diseases or who are undergoing transplantation. At present, the CD4+ Treg population has been extensively characterized, as a result of defined phenotypic and functional readouts. In this review article, we discuss the development and biology of CD8+ Tregs and their role in murine and human disease indications. A subset of CD8+ Tregs that lack the surface expression of CD28 (CD8+CD28− Treg) has proved efficacious in preclinical models. CD8+CD28− Tregs are present in healthy individuals, but their impaired functionality in disease renders them less effective in mediating immunosuppression. We primarily focus on harnessing CD8+ Treg cell therapy in the clinic to support current treatment for patients with autoimmune or inflammatory conditions.
Insights into the Regulation of Ciliary Disassembly
Authors: Patel Maulin M. , Tsiokas Leonidas
Published: November 2021

The primary cilium, an antenna-like structure that protrudes out from the cell surface, is present in most cell types. It is a microtubule-based organelle that serves as a mega-signaling center and is important for sensing biochemical and mechanical signals to carry out various cellular processes such as proliferation, migration, differentiation, and many others. At any given time, cilia length is determined by a dynamic balance of cilia assembly and disassembly processes. Abnormally short or long cilia can cause a plethora of human diseases commonly referred to as ciliopathies, including, but not limited to, skeletal malformations, obesity, autosomal dominant polycystic kidney disease, retinal degeneration, and bardet-biedl syndrome. While the process of cilia assembly is studied extensively, the process of cilia disassembly and its biological role(s) are less well understood. This review discusses current knowledge on ciliary disassembly and how different cellular processes and molecular signals converge to carry out this process. This information will help us understand how the process of ciliary disassembly is regulated, identify the key steps that need further investigation, and possibly design therapeutic targets for a subset of ciliopathies that are causally linked to defective ciliary disassembly.
Lipid Metabolism Disorders in the Comorbid Course of Nonalcoholic Fatty Liver Disease and Chronic Obstructive Pulmonary Disease
Authors: Kotlyarov Stanislav , Bulgakov Aleksei
Published: November 2021

Non-alcoholic fatty liver disease (NAFLD) is currently among the most common liver diseases. Unfavorable data on the epidemiology of metabolic syndrome and obesity have increased the attention of clinicians and researchers to the problem of NAFLD. The research results allow us to emphasize the systemicity and multifactoriality of the pathogenesis of liver parenchyma lesion. At the same time, many aspects of its classification, etiology, and pathogenesis remain controversial. Local and systemic metabolic disorders are also a part of the pathogenesis of chronic obstructive pulmonary disease and can influence its course. The present article analyzes the metabolic pathways mediating the links of impaired lipid metabolism in NAFLD and chronic obstructive pulmonary disease (COPD). Free fatty acids, cholesterol, and ceramides are involved in key metabolic and inflammatory pathways underlying the pathogenesis of both diseases. Moreover, inflammation and lipid metabolism demonstrate close links in the comorbid course of NAFLD and COPD.
The Inflammatory Lung Microenvironment; a Key Mediator in MSC Licensing
Authors: Dunbar Hazel , Weiss Daniel J , Rolandsson Enes Sara , Laffey John G , English Karen
Published: November 2021

Recent clinical trials of mesenchymal stromal cell (MSC) therapy for various inflammatory conditions have highlighted the significant benefit to patients who respond to MSC administration. Thus, there is strong interest in investigating MSC therapy in acute inflammatory lung conditions, such as acute respiratory distress syndrome (ARDS). Unfortunately, not all patients respond, and evidence now suggests that the differential disease microenvironment present across patients and sub-phenotypes of disease or across disease severities influences MSC licensing, function and therapeutic efficacy. Here, we discuss the importance of licensing MSCs and the need to better understand how the disease microenvironment influences MSC activation and therapeutic actions, in addition to the need for a patient-stratification approach.
Healthcare System-to-System Cost Variability in the Care of Pediatric Abdominal Pain-Associated Functional Gastrointestinal Disorders
Authors: Livitz Michelle , Friesen Alec S. , Glynn Earl F. , Schurman Jennifer V. , Colombo Jennifer M. , Friesen Craig A.
Published: November 2021

The purpose of this study was to assess cost variability in the care of abdominal pain-associated functional gastrointestinal disorders (AP-FGIDS) in youth across health systems, races, and specific AP-FGID diagnoses. Patients, aged 8–17 years, with a priority 1 diagnosis corresponding to a Rome IV defined AP-FGID were identified within the Health Facts® database. Total costs were obtained across the continuum of care including outpatient clinics, emergency department, and inpatient or observation units. Cost variability was described comparing different health systems, races, and diagnoses. Thirteen thousand two hundred and fourteen patients were identified accounting for 17,287 encounters. Total costs were available for 38.7% of the encounters. There was considerable variability in costs within and, especially, across health systems. Costs also varied across race, urban vs. rural site of care, and AP-FGID diagnoses. In conclusion, there was considerable variability in the costs for care of AP-FGIDs which is sufficient to support multi-site studies to understand the value of specific tests and treatments. Significant differences in costs by race merit further investigation to understand key drivers.
Improving Motor Skills in Early Childhood through Goal-Oriented Play Activity
Authors: Sutapa Panggung , Pratama Kukuh Wahyudin , Rosly Maziah Mat , Ali Syed Kamaruzaman Syed , Karakauki Manil
Published: November 2021

Goal-oriented play activity encourages children to exercise and triggers the movement of body muscles. Active muscles are stronger, more agile, faster, and more powerful. Purpose: The purpose of this study is to determine that goal-oriented play activity in early childhood improves motor skills. Methods: Forty children aged 4.5–6 years old were recruited and took part in a set of training activities divided into Posts 1–5. To pass each post, a child had to run, walk on a balance beam, move sticks, throw and catch the ball, and arrange blocks. Training was given three times every week for 12 weeks. Data collected consisted of running 25 m, walking on the balance beam, throwing the ball as far as possible, locomotor movement, arranging cans, and bouncing the ball. Paired t and Wilcoxon signed-rank tests were used for analysis. Results: The results showed that there were significant differences in the motor skills evaluated pre- and post-training with p < 0.05. Conclusion: All six training activities conducted for 12 weeks provided significant improvements in the motor skills areas in children aged 4.5–6 years old.
Development of a Quality-Controlled and Homogenised Long-Term Daily Maximum and Minimum Air Temperature Network Dataset for Ireland
Authors: Mateus Carla , Potito Aaron
Published: November 2021

Accurate long-term daily maximum and minimum air temperature series are needed to assess the frequency, intensity, distribution, and duration of extreme climatic events. However, quality control and homogenisation procedures are required to minimise errors and inhomogeneities in climate series before the commencement of climate data analysis. A semi-automatic quality control procedure consisting of climate consistency, internal consistency, day-to-day step-change, and persistency tests was applied for 12 long-term series registered in Ireland from 1831–1968, Armagh Observatory (Northern Ireland) from 1844–2018, and for 21 short-term series dating to the mid-19th century. There were 976,786 observations quality-controlled, and 27,854 (2.9%) values flagged. Of the flagged records, 98.5% (n = 27,446) were validated, 1.4% (n = 380) corrected and 0.1% (n = 28) deleted. The historical long-term quality-controlled series were merged with the modern series quality-controlled by Met Éireann and homogenised using the software MASHv3.03 in combination with station metadata for 1885–2018. The series presented better homogenisation outcomes when homogenised as part of smaller regional networks rather than as a national network. The homogenisation of daily, monthly, seasonal, and annual series improved for all stations, and the homogenised records showed stronger correlations with the Central England long-term temperature series.
Testing the CMIP6 GCM Simulations versus Surface Temperature Records from 1980–1990 to 2011–2021: High ECS Is Not Supported
Authors: Scafetta Nicola
Published: November 2021

The last-generation CMIP6 global circulation models (GCMs) are currently used to interpret past and future climatic changes and to guide policymakers, but they are very different from each other; for example, their equilibrium climate sensitivity (ECS) varies from 1.83 to 5.67 °C (IPCC AR6, 2021). Even assuming that some of them are sufficiently reliable for scenario forecasts, such a large ECS uncertainty requires a pre-selection of the most reliable models. Herein the performance of 38 CMIP6 models are tested in reproducing the surface temperature changes observed from 1980–1990 to 2011–2021 in three temperature records: ERA5-T2m, ERA5-850mb, and UAH MSU v6.0 Tlt. Alternative temperature records are briefly discussed but found to be not appropriate for the present analysis because they miss data over large regions. Significant issues emerge: (1) most GCMs overestimate the warming observed during the last 40 years; (2) there is great variability among the models in reconstructing the climatic changes observed in the Arctic; (3) the ocean temperature is usually overestimated more than the land one; (4) in the latitude bands 40° N–70° N and 50° S–70° S (which lay at the intersection between the Ferrel and the polar atmospheric cells) the CMIP6 GCMs overestimate the warming; (5) similar discrepancies are present in the east-equatorial pacific region (which regulates the ENSO) and in other regions where cooling trends are observed. Finally, the percentage of the world surface where the (positive or negative) model-data discrepancy exceeds 0.2, 0.5 and 1.0 °C is evaluated. The results indicate that the models with low ECS values (for example, 3 °C or less) perform significantly better than those with larger ECS. Therefore, the low ECS models should be preferred for climate change scenario forecasts while the other models should be dismissed and not used by policymakers. In any case, significant model-data discrepancies are still observed over extended world regions for all models: on average, the GCM predictions disagree from the data by more than 0.2 °C (on a total mean warming of about 0.5 °C from 1980–1990 to 2011–2021) over more than 50% of the global surface. This result suggests that climate change and its natural variability remain poorly modeled by the CMIP6 GCMs. Finally, the ECS uncertainty problem is discussed, and it is argued (also using semi-empirical climate models that implement natural oscillations not predicted by the GCMs) that the real ECS could be between 1 and 2 °C, which implies moderate warming for the next decades.
Depth Profile Analysis of the Modified Layer of Poly(vinyltrimethylsilane) Films Treated by Direct-Current Discharge
Authors: Piskarev Mikhail , Skryleva Elena , Gilman Alla , Senatulin Boris , Zinoviev Alexander , Syrtsova Daria , Teplyakov Vladimir , Kuznetsov Alexander
Published: November 2021

Previously, we found that modification of the membrane surface from polyvinyltrimethylsilane (PVTMS) by treatment with low-temperature plasma induced by low pressure DC discharge leads to a significant increase in gas separation characteristics. To understand the mechanism of this phenomenon, in this article XPS combined with precision etching 10 keV beam of Ar2500+ clusters was used for depth profiling of PVTMS spin-coated films before and after DC discharge treatment. The etching craters depths were measured by stylus surface profiler. The average etching rate of the untreated PVTMS film by Ar2500+ clusters was defined (230 nm/min). It was found that the low temperature plasma treatment of PVTMS leads to a sharp increase in the oxygen concentration on a surface with a simultaneous decrease in the carbon content. The experimental data obtained indicate also that the treatment of PVTMS film by plasma leads not only to a change in the chemical structure of the surface, but also to the formation of a gradient subsurface layer with a thickness of about 50 nm.
Effect of Process Parameters and Layer Thickness on the Quality and Performance of Ti-6Al-4V Fabricated by Selective Laser Melting
Authors: Jing Yanlong , Wang Peng , Yan Xiaoling
Published: November 2021

To improve the quality of thick powder bed and realize the matching of thick powder bed and thin powder bed in the later stage, the influence of process parameters for the single-track, multi-layer fabrication, relative density, surface quality, defect, remelting, and boundary optimization performance of different layer thicknesses of Ti-6Al-4V fabricated by selective laser melting were investigated. It is more conducive to the stable forming of single-track when the point distance is half the diameter of the laser beam, and the exposure time is appropriately extended. The thin powder bed needs the corresponding point distance and exposure time under the laser power of 280–380 W to obtain high-density specimens. The thick powder bed needs to be able to ensure the formation of high-quality specimens under the smaller point distance and longer exposure time under higher laser power of 380 W. Both thick powder bed and thin powder bed will cause un-melted defects between molten pools, spheroidization defects caused by splashing, and microporous defects. The remelting process can significantly improve the surface quality of the formed specimen, but the surface quality of the thick powder bed is worse than that of the thin powder bed. The boundary quality of thick powder bed is worse than that of thin powder bed, and the boundary shape has a greater influence on the quality of the SLM forming boundary. Different strategies should be adopted to form the boundary of different shapes. Increasing the boundary count and increasing the laser power are more conducive to the improvement of boundary quality.
ZnO Nano-Flowers Assembled on Carbon Fiber Textile for High-Performance Supercapacitor’s Electrode
Authors: Abbas Qasim , Javed Muhammad , Ahmad Awais , Siyal Sajid , Asim Idrees , Luque Rafael , Albaqami Munirah , Tighezza Ammar
Published: November 2021

Herein, a crystalline nano-flowers structured zinc oxide (ZnO) was directly grown on carbon fiber textile (CFT) substrate via a simple hydrothermal process and fabricated with a binder-free electrode (denoted as ZnO@CFT) for supercapacitor (SC) utilization. The ZnO@CFT electrode revealed a 201 F·g−1 specific capacitance at 1 A·g−1 with admirable stability of >90% maintained after 3000 cycles at 10 A·g−1. These impressive findings are responsible for the exceedingly open channels for well-organized and efficient diffusion of effective electrolytic conduction via ZnO and CFT. Consequently, accurate and consistent structural and morphological manufacturing engineering is well regarded when increasing electrode materials’ effective surface area and intrinsic electrical conduction capability. The crystalline structure of ZnO nano-flowers could pave the way for low-cost supercapacitors.
RETRACTED: Influence of Different Rotations of Organic Formamidinium Molecule on Electronic and Optical Properties of FAPbBr3 Perovskite
Authors: Al-Kahtani Abdullah , Tabassum Sobia , Raya Indah , Khlewee Ibrahim , Chupradit Supat , Davarpanah Afshin , Elveny Marischa , Ali Shafaqat
Published: November 2021

Hybrid organic–inorganic halide perovskites (HOIPs) have recently represented a material breakthrough for optoelectronic applications. Obviously, studying the interactions between the central organic cation and the Pb-X inorganic octahedral could provide a better understanding of HOIPs. In this work, we used a first-principles theoretical study to investigate the effect of different orientations of central formamidinium cation (FA+) on the electronic and optical properties of FAPbBr3 hybrid perovskite. In order to do this, the band structure (with and without spin–orbit coupling (SOC)), density of states (DOS), partial density of states (PDOS), electron density, distortion index, bond angle variance, dielectric function, and absorption spectra were computed. The findings revealed that a change in the orientation of FA+ caused some disorders in the distribution of interactions, resulting in the formation of some specific energy levels in the structure. The interactions between the inorganic and organic parts in different directions create a distortion index in the bonds of the inorganic octahedral, thus leading to a change in the volume of PbBr6. This is the main reason for the variations observed in the electronic and optical properties of FAPbBr3. The obtained results can be helpful in solar-cell applications.
Effects of Zr/(Zr+Ti) Molar Ratio on the Phase Structure and Hardness of TixZr1−xN Films
Authors: Zhang Jun , Peng Lijing , Wang Xiaoyang , Liu Dongling , Wang Nan
Published: November 2021

TixZr1−xN hard films with Zr/(Zr+Ti) molar ratios from 20% to 80% were prepared by multi-arc ion plating using any two of elemental Ti, elemental Zr, and TiZr alloy targets. The as-deposited TixZr1−xN films displayed similar surface and fracture cross-section morphologies and thicknesses. The effects of Zr/(Zr+Ti) molar ratio on the phase composition, preferred growth orientation, and hardness of the films were discussed. The results showed that the as-deposited films had a face-centered cubic structure and exhibited the typical characteristics of substitutional solid solutions. The lattice constant of the films increased monotonically with increasing Zr/(Zr+Ti) molar ratio. Two preferred growth orientations, corresponding to the two hardness peak values, occurred symmetrically at Zr/Ti molar ratios of 40:60 and 60:40. An inflection point with a small reduction in hardness was observed at the Zr/Ti molar ratio of 50:50.
Edible Films on Meat and Meat Products
Authors: Song Dong-Heon , Hoa Van Ba , Kim Hyoun Wook , Khang Sun Moon , Cho Soo-Hyun , Ham Jun-Sang , Seol Kuk-Hwan
Published: November 2021

In 2018, the worldwide consumption of meat was 346.14 million tonnes, and this is expected to increase in the future. As meat consumption increases, the use of packaging materials is expected to increase along with it. Petrochemical packaging materials which are widely used in the meat processing industry, take a long time to regenerate and biodegrade, thus they adversely affect the environment. Therefore, the necessity for the development of eco-friendly packaging materials for meat processing, which are easily degradable and recyclable, came to the fore. The objective of this review is to describe the application of natural compound-derived edible films with their antioxidant and antibacterial activities in meat and meat products. For several decades, polysaccharides (cellulose, starch, pectin, gum, alginate, carrageenan and chitosan), proteins (milk, collagen and isolated soy protein) and lipids (essential oil, waxes, emulsifiers, plasticizers and resins) were studied as basic materials for edible films to reduce plastic packaging. There are still high consumer demands for eco-friendly alternatives to petrochemical-based plastic packaging, and edible films can be used in a variety of ways in meat processing. More efforts to enhance the physiological and functional properties of edible films are needed for commercial application to meat and meat products.
Design and Preparation of PU/EP Blend Resin Grafted by Hydrophilic Molecular Segments
Authors: Lu Gang , Shuai Changgeng , Liu Yinsong , Yang Xue , Hu Xiaoyang
Published: November 2021

Film-forming resins, as carriers of antifouling coatings, play an essential role in the functional performance of coatings. With the gradual promotion of coatings in the field of marine antifouling, the preparation of film-forming resins containing hydrophilic chain segments is urgently needed to give full play to the functional and time-sensitive performance of antifouling coatings. In this paper, the single-ended isocyanate group (NCO) polyurethane (PU) prepolymer with hydrophilic chain segments was prepared and grafted onto an epoxy resin (EP) molecular chain to obtain the PU/EP grafted blend. Successful preparation of the PU/EP grafted blends was confirmed by infrared spectrum analysis. Simultaneously, the grafted blend was cured, and its hydrophilicity and mechanical properties were also tested. The results demonstrate that the grafted method can effectively improve the hydrophilicity of the film-forming resin while maintaining its mechanical properties. It can be concluded from the hydrophilic and mechanical properties of the materials that the comprehensive properties of PU/EP grafted blends are the best when the PU content is between 40% and 50%. The hanging plate test showed that the antifouling effect of the antifouling coating prepared by hydrophilic modified PU/EP film-forming resin was better than that of the traditional antifouling coating under the experimental conditions.
Effective Detoxification of Aflatoxin B1 and Ochratoxin A Using Magnetic Graphene Oxide Nanocomposite: Isotherm and Kinetic Study
Authors: Abbasi Pirouz Atena , Selamat Jinap , Sukor Rashidah , Noorahya Jambari Nuzul
Published: November 2021

One of the approaches for reducing exposure to mycotoxins is to lessen their bioavailability by applying nanocomposite adsorbents. Magnetic graphene oxide (MGO) is a new class of nanostructured multifunctional nanocomposite materials, which play a vital role as an adsorbent. The primary aim of this study is to apply response surface methodology (RSM) to optimize the influence of pH within the range of 3 to 7, time (3–7 h), and temperature (30–50 °C), on the simultaneous detoxification of aflatoxin B1 (AFB1) and ochratoxin A (OTA) by using MGO. The optimal condition was obtained at pH 5, 5 h, and 40 °C. Further investigation of the adsorption evaluation was carried out by studying different parameters, such as the influence of contact time, initial mycotoxins concentration, and temperature. According to the experimental data, it can be concluded that the pseudo-second-order kinetic model and the Freundlich isotherm fitted well. The capability of adsorption for the Freundlich model was calculated as 153 and 95 ng/g for AFB1 and OTA, respectively. The thermodynamic study showed that the sorption studies act spontaneously as an exothermic process. These findings suggest that the application of MGO as a nanocomposite is of great significance for the detoxification of mycotoxins.
A Cognitive Diagnostic Module Based on the Repair Theory for a Personalized User Experience in E-Learning Software
Authors: Krouska Akrivi , Troussas Christos , Sgouropoulou Cleo
Published: November 2021

This paper presents a novel cognitive diagnostic module which is incorporated in e-learning software for the tutoring of the markup language HTML. The system is responsible for detecting the learners’ cognitive bugs and delivering personalized guidance. The novelty of this approach is that it is based on the Repair theory that incorporates additional features, such as student negligence and test completion times, in its diagnostic mechanism; also, it employs a recommender module that suggests students optimal learning paths based on their misconceptions using descriptive test feedback and adaptability of learning content. Considering the Repair theory, the diagnostic mechanism uses a library of error correction rules to explain the cause of errors observed by the student during the assessment. This library covers common errors, creating a hypothesis space in that way. Therefore, the test items are expanded, so that they belong to the hypothesis space. Both the system and the cognitive diagnostic tool were evaluated with promising results, showing that they offer a personalized experience to learners.
Nanocrystalline Materials: Synthesis, Characterization, Properties, and Applications
Authors: Kushwaha Amanendra K. , John Merbin , Misra Manoranjan , Menezes Pradeep L.
Published: November 2021

Nanostructuring is a commonly employed method of obtaining superior mechanical properties in metals and alloys. Compared to conventional polycrystalline counterparts, nanostructuring can provide remarkable improvements in yield strength, toughness, fatigue life, corrosion resistance, and hardness, which is attributed to the nano grain size. In this review paper, the current state-of-the-art of synthesis methods of nanocrystalline (NC) materials such as rapid solidification, chemical precipitation, chemical vapor deposition, and mechanical alloying, including high-energy ball milling (HEBM) and cryomilling was elucidated. More specifically, the effect of various process parameters on mechanical properties and microstructural features were explained for a broad range of engineering materials. This study also explains the mechanism of grain strengthening using the Hall-Petch relation and illustrates the effects of post-processing on the grain size and subsequently their properties. This review also reports the applications, challenges, and future scope for the NC materials.
Gallium Nitride Metalens for Image Decryption
Authors: Chen Meng-Hsin , Li Jia-Ying , Su Vin-Cent
Published: November 2021

As the demand for secure digital data continues to increase, image encryption and decryption have recently received tremendous attention. The rapid development of ultrathin metasurfaces has mainly been driven by the desire for the introduction of novel methods with which electromagnetic waves can be manipulated. As a promising application of metasurfaces, metalenses have shown great potential to replace bulky traditional optical devices. In this work, we present that the images produced by a commercially available projector are encrypted by using the color superposition principle, and the fabricated metalens is subsequently utilized to perform image decryption with an incidence made of white light-emitting diodes (LEDs). The correct positions for image decryption are carefully found by three distinct diode lasers as incident light sources. Recent investigations show that high-performance metalenses can be successfully developed once the suitable dielectric material is chosen. As a consequence, our metalens of high performance is composed of hexagon-resonated elements (HREs) made of gallium nitride (GaN) and is capable of resolving line width as small as 870 nm. The metalens with a smaller diameter of 8 μm is numerically simulated with a diffraction-limited focusing efficiency as high as 92%. This work once again shows that GaN metalenses, as future optics, have great prospects in expanding widespread applications in the near future.
Beryl Reference Materials for In Situ Oxygen Isotope Determination
Authors: Ling Xiaoxiao , Li Qiuli , Feng Lianjun , Zhang Di , Liu Yu , Tang Guoqiang , Li Jiao , Wu Shitou , Huang Liangliang , Li Tiejun , Liu Yan , Werner Ronald , Li Xianhua
Published: November 2021

The mineral beryl (Be3Al2(SiO3)6) has the most abundant phase with industrial value for extracting a critical metal—beryllium. Due to multi-stage, fluid-induced growth, individual beryl grains may yield complex geochemical records, revealing variations in the oxygen isotopes of the fluids from which they crystallize. Secondary ion mass spectrometry (SIMS) with high sensitivity and high spatial resolution represents a good tool for in situ isotopic analysis. SIMS oxygen analyses require matrix-matched reference materials to calibrate instrumental mass fractionations during measurement. In this work, the oxygen isotope homogeneities of six beryl samples with different compositions (BS1, BS2, BS3, BS4, BS5, and BS6) were documented by SIMS. These samples’ recommended oxygen isotope compositions were characterized by laser fluorination isotope ratio mass spectrometry (IRMS). This study suggests that there is no matrix effect related to composition variation in beryl SIMS oxygen isotope analysis. The recommended δ18O values of the four reference materials, BS1, BS2, BS4, and BS5, were 15.01 ± 0.34‰ (2 standard deviations, 2 SD), 7.53 ± 0.16‰ (2 SD), 2.38 ± 0.14‰ (2 SD), and 10.72 ± 0.44‰ (2 SD), respectively. Therefore, BS1, BS2, BS4, and BS5 are recommended as suitable reference materials for in situ mineral beryl oxygen isotope microanalysis.
Microdiamonds in Alkalic Dolerites from the North China Craton: FTIR and C Isotopic Characteristics
Authors: Cai Yitao , Cao Zhengqi , Liu Fei , Li Kan , Li Long , Yang Jingsui
Published: November 2021

Most of the diamond deposits in China are in the North China Craton. In addition to gem diamonds in kimberlite, a large number of microdiamonds have also been discovered in alkaline dolerites. These microdiamonds show very different characteristics from those recovered in kimberlite. Here, we report the morphology, colour, nitrogen contents, and carbon isotopic compositions of the diamonds recovered from the alkalic dolerites in eastern China. The microdiamonds are mainly cube and rhombic dodecahedron with diameters of 0.2 to 0.6 mm. Infrared spectrum analysis shows that these microdiamonds are mostly type Ib with a small amount of type Ia. The Y centre is obvious in type Ib diamond. Modelling mantle residence times for the IaAB diamonds is about 550 Ma. Nitrogen contents of the diamonds range from 4.5–503 ppm, with a median value of 173 ppm. The total δ13C range of the microdiamonds varies between −18.6 and −21.1‰ and are similar to those of ophiolite diamond.
Comparison of CrN, AlN and TiN Diffusion Barriers on the Interdiffusion and Oxidation Behaviors of Ni+CrAlYSiN Nanocomposite Coatings
Authors: Zhu Lijuan , Feng Chun , Zhu Shenglong , Wang Fuhui , Yuan Juntao , Wang Peng
Published: November 2021

CrN, AlN, TiN layer were prepared as diffusion barriers between the K417 substrate and Ni+CrAlYSiN nano composite coatings via vacuum arc evaporation. Oxidation kinetics and microstructure evaluation of these nano coating systems at 1000 °C after 100 h were studied. Results show that the AlN layer showed good thermodynamic stability, effectively inhibited the interdiffusion between the coating and the substrate, improved the oxidation resistance of Ni+CrAlYSiN nano composite coatings, and a single-layer Al2O3 film was formed on the coating. The CrN layer was decomposed, which did not block the diffusion of elements and had little effect on the oxidation resistance of the Ni+CrAlYSiN nano composite coating. The TiN layer effectively prevented the interdiffusion between the coating and the substrate. However, it deteriorated the oxidation resistance of the composite coating. Similar to the Ni+CrAlYSiN coating without a diffusion barrier, a double-layer oxide film structure with Al2O3 as the inner layer and Ni(Al,Cr)2O4 as the outer layer formed on the Ni+CrAlYSiN nano composite coatings with the CrN or TiN diffusion barrier.
Leaf Elemental Concentrations, Stoichiometry, and Resorption in Guam’s Coastal Karst Forests
Authors: Marler Thomas E.
Published: November 2021

Greater knowledge concerning the interspecific diversity of the plant leaf ionome is required to effectively understand the spatiotemporal dynamics of biogeochemistry, but Micronesia has been ignored in this literature. The objectives of this study were to quantify the leaf ionome, resorption efficiency, and stoichiometry of leaves from 25 plant species representing Guam’s coastal karst forests. Carbon and nitrogen were quantified by dry combustion, and other minerals and metals were quantified by spectrometry. Nitrogen and calcium concentrations in Guam’s green leaves exceeded the published global means, but manganese and copper concentrations were less than the global means. The remainder of the elements were within the expected ranges. Nutrient resorption rates exhibited a decreasing order of potassium > phosphorus > nitrogen > zinc > copper. The term “accretion efficiency” is introduced to describe the accumulation of an element throughout leaf aging and senescence, and calcium and iron exhibited substantial accretion efficiency in this study. Stoichiometry relations indicated that Guam’s karst forest is most limited by phosphorus and then secondarily limited by nitrogen, although several individual taxa exhibited co-limitation by potassium. Five of the species are officially listed on extinction threat lists. Of these, the Malvaceae tree Heriteria longipetiolata exhibited leaf traits depicting the most recalcitrant litter characteristics, and the Fabaceae tree Serianthes nelsonii exhibited leaf traits depicting the most labile litter characteristics. The contributions of these two tree species to spatiotemporal diversity in biogeochemistry appear to be profound, indicating species recovery efforts are of paramount importance for maintaining ecosystem function and soil heterotroph biodiversity in northern Guam.
Establishment of a New Filamentous Cyanobacterial Genus, Microcoleusiopsis gen. nov. (Microcoleaceae, Cyanobacteria), from Benthic Mats in Open Channel, Jiangxi Province, China
Authors: Geng Ruozhen , Li Wenke , Chao Aimin , Guo Xiaoyu , Li Hua , Yu Gongliang , Li Renhui
Published: November 2021

Cyanobacterial taxonomic studies performed by using the modern approaches always lead to creation of many new genera and species. During the field survey for cyanobacterial resources in China, a filamentous cyanobacterial strain was successfully isolated from a microbial mat attached to rock surfaces of the Ganfu Channel, Jiangxi Province, China. This strain was morphologically similar to the cyanobacterial taxa belonging to the genera Microcoleus and Phormidium. The phylogenetic analyses based on 16S rRNA gene sequences showed that this strain formed a well-supported clade, close to the filamentous genera Microcoleus, Tychonema, and Kamptonema. The maximum similarity of 16S rRNA gene sequence of this strain with the related genera was 95.04%, less than the threshold for distinguishing bacterial genus. The ITS secondary structures also distinguish this strain from the related cyanobacterial genera. Therefore, combined with morphology, 16S rRNA gene sequence, and ITS secondary structures, a novel cyanobacterial genus here as Microcoleusiopsis was established, with the species type as Microcoleusiopsis ganfuensis.
Three New Diatom Species from Spring Habitats in the Northern Apennines (Emilia-Romagna, Italy)
Authors: Cantonati Marco , Bilous Olena , Angeli Nicola , van Wensen Liesbeth , Lange-Bertalot Horst
Published: November 2021

Using light (LM, including plastid characterization on fresh material) and scanning electron microscopy (SEM), as well as a thorough morphological, physical, chemical, and biological characterization of the habitats, the present study aims at describing three species new to science. They belong to the genera Eunotia Ehrenb., Planothidium Round and L. Bukht., and Delicatophycus M.J. Wynne, and were found in two contrasting spring types in the northern Apennines. The three new species described differ morphologically from the most similar species by: less dense striae and areolae, and the absence of a ridge at the valve face-mantle transition (SEM feature) [Eunotia crassiminor Lange-Bert. et Cantonati sp. nov.; closest established species: Eunotia minor (Kütz.) Grunow]; narrower and shorter cells [Planothidium angustilanceolatum Lange-Bert. et Cantonati sp. nov.; most similar species: Planothidium lanceolatum (Bréb. ex Kütz.) Lange-Bert.]; barely-dorsiventral symmetry, set off ends, and lower density of the central dorsal striae [Delicatophycus crassiminutus Lange-Bert. et Cantonati sp. nov.; most similar species: Delicatophycus minutus M.J.Wynne]. Two of the three species we described are separated from the closest species by dimensions. Their description improved knowledge on two taxa (Eunotia minor s.l. and Planothidium lanceolatum s.l.) likely to be only partially resolved species complexes. We could also refine knowledge on the ecological profiles of the three newly-described species. Eunotia crassiminor sp. nov., as compared to Eunotia minor, appears to occur in colder inland waters with a circumneutral pH and a strict oligotrophy as well with respect to nitrogen. The typical habitat of Planothidium angustilanceolatum sp. nov. appears to be oligotrophic mountain flowing springs with low conductivity. Delicatophycus crassiminutus sp. nov. was observed only in limestone-precipitating springs, and is therefore likely to be restricted to hard water springs and comparable habitats where CO2 degassing leads to carbonate precipitation. Springs are a unique but severely threatened wetland type. Therefore, the in-depth knowledge of the taxonomy and ecology of characteristic diatom species is important, because diatoms are excellent indicators of the quality and integrity of these peculiar ecosystems in the face of direct and indirect human impacts.
Floral Trait and Mycorrhizal Similarity between an Endangered Orchid and Its Natural Hybrid
Authors: Calevo Jacopo , Bazzicalupo Miriam , Adamo Martino , Robustelli della Cuna Francesco Saverio , Voyron Samuele , Girlanda Mariangela , Duffy Karl J. , Giovannini Annalisa , Cornara Laura
Published: November 2021

Hybridization can often lead to the formation of novel taxa which can have traits that resemble either or both parental species. Determining the similarity of hybrid traits to parental taxa is particularly important in plant conservation, as hybrids that form between rare and common taxa may more closely resemble a rare parental species, thereby putting the rare parental taxon at further risk of extinction via increased backcrossing and introgression. We investigated the floral (morphological and chemical) traits and orchid mycorrhizal (OrM) fungal associations of the endangered orchid Orchis patens, its more common sister species O. provincialis, and their natural hybrid O. × fallax in natural sympatric populations. We found that both morphological and chemical floral traits of O. × fallax are shared by the parents but are more similar to O. patens than O. provincialis. OrM fungi were shared among all three taxa, indicating that the availability of OrM fungi should not represent a barrier to establishment of individuals of any of these taxa. These results suggest that O. × fallax may be able to expand its distribution within a similar niche to O. patens. This highlights the importance of quantifying differences between hybrids and parental taxon in species conservation planning.
Are Introduced Alien Species More Predisposed to Invasion in Recipient Environments If They Provide a Wider Range of Services to Humans?
Authors: Yessoufou Kowiyou , Ambani Annie Estelle
Published: November 2021

The drivers of invasion success of alien species remain, to some extent, a matter of debate. Here, we suggest that the services (the benefits humans obtain from a species) provided by alien plants could predict their invasion status, such that alien species providing more services would be more likely to be invasive than not. The rationale for this expectation is that alien species providing multiple services stand a better chance of being introduced in various numbers and multiple times outside their native range (propagule pressure theory). We investigated this hypothesis on alien woody species in South Africa. First, we defined 12 services provided by all the 210 known naturalized alien woody plants in South Africa. Then, we tested for a phylogenetic signal in these services using a DNA barcode-based phylogeny. Finally, we tested for potential links between the services and invasion status by fitting GLM models with appropriate error families. We found a phylogenetic signal in most services, suggesting that closely related species tend to provide similar services. Counter-intuitively, we consistently found that alien non-invasive species tend to provide more services, or even unique services, in comparison to alien invasive species. Although alternative scenarios are plausible to explain this unexpected finding, we speculate that harvesting alien plants for human benefits may limit their invasion ability. This warrants further investigation.
Coral Communities on Marginal High-Latitude Reefs in West Australian Marine Parks
Authors: Ross Claire L. , French Ben , Lester Emily K. , Wilson Shaun K. , Day Paul B. , Taylor Michael D. , Barrett Neville
Published: November 2021

Many temperate reefs are experiencing a shift towards a greater abundance of tropical species in response to marine heatwaves and long-term ocean warming worldwide. Baseline data for coral communities growing in high-latitude reefs is required to better understand ecosystem changes over time. In this study, we explore spatial and temporal trends in the distribution of coral communities from 1999 to 2019 at 118 reef sites within the five marine parks located in the south-west of Western Australia (WA) between 30° to 35° S. Our estimates of coral cover were generally low (<5%), except for a few sites in Jurien Bay Marine Park and Rottnest Island Marine Reserve where coral cover was 10% to 30%. Interannual changes in genera assemblages were detected but were not consistent over time, whereas significant temporal increases in coral cover estimates were found at the lowest latitude site in Jurien Bay. Coral assemblages were primarily distinguished by Turbinaria spp. at Marmion Marine Park and Ngari Capes Marine Park, and Pocillopora spp. and Dipsastraea spp. at Rottnest Island and Jurien Bay. Our findings suggest that conditions in south-west WA are favorable to the ongoing survival of existing genera and there were minimal signs of expansion in coral cover at most study sites. Coral cover and composition on these reefs may, however, change with ongoing ocean warming and increased occurrence of marine heatwaves. This study provides a valuable benchmark for assessing future changes in coral assemblages and highlights the need for targeted hard-coral surveys to quantify subtle changes in high-latitude coral community assemblages.
Annotated Checklist of the Lichenicolous Fungi of Hungary
Authors: Varga Nóra , Lőkös László , Farkas Edit
Published: November 2021

Knowledge of lichenicolous fungi is limited at a worldwide level and needs further basic information, as in the case of Central and Southern Europe. The literature sources for “Revised checklist of the Hungarian lichen-forming and lichenicolous fungi” by Lőkös and Farkas in 2009 contained 54 lichenicolous and other microfungi species of 38 genera. Due to recent field studies and microscopic work, the number of known species has increased to 104 lichenicolous species in 64 genera during the last decade, including 53 new species for the country. Old records of five species were confirmed by new collections. Key characteristics of some of the most interesting species are illustrated by microscopic views and two distribution maps are provided. Recent biodiversity estimates suggest that the number of currently known species could be 1.5 (–2) times higher with more detailed work on field collections. Although lichenicolous fungi have been less well studied in Hungary in the past, the relative diversity of lichenicolous fungi there, as indicated by Zhurbenko’s lichenicolous index, was found to be slightly higher than the mean value calculated for the world.