bluuebunny/crossref_metadata_2025 huggingface dataset:
Hot Deformation Characteristics of 18Cr-5Ni-4Cu-N Stainless Steel Using Constitutive Equation and Processing Map
Authors: Fu Xiao-yang , Bai Pu-cun , Yang Ji-chun
Published: January 2020

The hot deformation of 18Cr-5Ni-4Cu nitrogen-alloyed austenitic stainless steel was tested with a Gleeble-1500D simulator in the temperature range of 1273–1473 K and in the strain rate range of 0.01–10 s−1. The Zener-Hollomon parameter method was used to construct a constitutive equation for high-temperature plastic deformation. The energy dissipation diagram of the material was calculated based on dynamic material modelling (DMM). The microstructural variations were characterized via X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) with energy dispersive spectroscopy (EDS) and transmission electron microscopy (TEM). The thermodynamic calculation results showed that the addition of nitrogen to 18Cr-5Ni-4Cu steel promoted the formation of Cr2N and gas phases and expanded the austenite phase region; these results were consistent with the XRD test results of the solid solution sample. The hot deformation activation energy after nitrogen addition was 556.46 kJ∙mol−1. The processing map predicted that the optimum hot working regimes were in the temperature range of 1416–1461 K, where ln ε ˙ was 0.75–1 on the power dissipation map. At high temperatures and a small strain rate, dynamic recrystallization easily occurred. The TEM analyses showed that nano-scale M23C6 and Cr2N precipitated at the grain boundary, and NbC with a diameter of approximately 150 nm appeared along the grain boundary, resulting in grain boundary strengthening. The phase precipitation results were consistent with the Thermo-Calc calculation results. The nitrogen solid solution in the steel promoted the precipitation of nitrides, which caused grain boundary strengthening. Thus, the grain boundary stress increased and wedge-shaped grain boundary cracks formed.
Dynamic Changes in Serum Metabolomic Profiles of Growing Pigs Induced by Intravenous Infusion of Sodium Butyrate
Authors: Wang Hongyu , Ren Erdu , Xiang Xiaoe , Su Yong , Zhu Weiyun
Published: January 2020

This study aimed to explore the dynamic changes in metabolite profiles and metabolism pathways in the serum of growing pigs by intravenous infusion of sodium butyrate (SB). Fourteen crossbred growing barrows (BW = 23.70 ± 1.29 kg) fitted with jugular cannula were randomly allocated to the SB and control (Con) groups, each group consisted of seven replicates (pens), with one pig per pen. At 9:00 of each day during the experimental period, pigs in the SB group were infused with 10 mL of SB (200 mmol/L, pH 7.4, 37 °C) via precaval vein, while the Con group was treated with the same volume of physiological saline. On day 4, the blood of each pig was collected at 0, 30, 60, and 120 min after the intravenous infusion. Metabolites in the serum were detected by gas chromatograph-mass spectrometry analysis. Pathway analysis of metabolomic profiles showed that the differential metabolites mainly enriched in amino acid metabolism, lipid-related metabolism, and the tricarboxylic acid (TCA) cycle. More importantly, the relative concentrations of all eight essential amino acids, five non-essential amino acids, and two amino acid derivatives were decreased by the parenteral SB. In addition, SB significantly increased the relative concentrations of eicosanoic acid and octadecanoic acid and decreased the relative concentration of glycerol-3-phosphate at 0 min (three days after intravenous infusion of SB), which suggests that parenteral SB may increase stearates mobilization and decrease the biosynthesis of stearates. In conclusion, intravenous infusion of SB may induce more amino acids to synthesize proteins and affect fat metabolism through increasing fat mobilization and decreasing the biosynthesis of stearates. However, a further study is needed to understand the mechanism of extensive metabolic pathway changes induced by parenteral SB.
Effects of Bacillus subtilis WB60 and Lactococcus lactis on Growth, Immune Responses, Histology and Gene Expression in Nile Tilapia, Oreochromis niloticus
Authors: Won Seonghun , Hamidoghli Ali , Choi Wonsuk , Park Youngjin , Jang Won Je , Kong In-Soo , Bai Sungchul C.
Published: January 2020

An eight-week feeding trial was conducted to evaluate the effects of a basal control diet (CON), Bacillus subtilis at 107 (BS7) and at 108 CFU/g diet (BS8), Lactococcus lactis at 107 CFU/g (LL7) and at 108 CFU/g diet (LL8), and oxytetracycline (OTC) at 4 g/kg diet on Nile tilapia. Fish with initial body weight of 2.83 ± 0.05 g (mean ± SD) were fed two times a day. Weight gain, specific growth rate, feed efficiency, protein efficiency ratio and lysozyme activity of fish fed BS8, LL8 and LL7 diets were significantly higher than those of fish fed CON diet (p < 0.05). Superoxide dismutase and myeloperoxidase activity of fish fed BS8, LL8, BS7, LL7 and OTC diets were significantly higher than those of fish fed CON diet. Intestinal villi length and muscular layer thickness of fish fed BS8, LL8 and LL7 diets were significantly higher than those of fish fed CON and OTC diets. Also, heat shock protein 70 (HSP70), interleukin (IL-1β), interferon-gamma (IFN-γ) and tumour necrosis factor (TNF-α) gene expression of fish fed BS8 and LL8 diets were significantly higher than those of fish fed CON diet. After 13 days of challenge test, cumulative survival rate of fish fed BS8 and LL8 diets were significantly higher than those of fish fed CON, BS7 and OTC diets. Based on these results, B. subtilis and L. lactis at 108 (CFU/g) could replace antibiotics, and have beneficial effects on growth, immunity, histology, gene expression, and disease resistance in Nile tilapia.
Modelling Fungal Growth, Mycotoxin Production and Release in Grana Cheese
Authors: Camardo Leggieri Marco , Pietri Amedeo , Battilani Paola
Published: January 2020

No information is available in the literature about the influence of temperature (T) on Penicillium and Aspergillus spp. growth and mycotoxin production on cheese rinds. The aim of this work was to: (i) study fungal ecology on cheese in terms of T requirements, focusing on the partitioning of mycotoxins between the rind and mycelium; and (ii) validate predictive models previously developed by in vitro trials. Grana cheese rind blocks were inoculated with A. versicolor, P. crustosum, P. nordicum, P. roqueforti, and P. verrucosum, incubated at different T regimes (10–30 °C, step 5 °C) and after 14 days the production of mycotoxins (ochratoxin A (OTA); sterigmatocystin (STC); roquefortine C (ROQ-C), mycophenolic acid (MPA), Pr toxin (PR-Tox), citrinin (CIT), cyclopiazonic acid (CPA)) was quantified. All the fungi grew optimally around 15–25 °C and produced the expected mycotoxins (except MPA, Pr-Tox, and CIT). The majority of the mycotoxins produced remained in the mycelium (~90%) in three out of five fungal species (P. crustosum, P. nordicum, and P. roqueforti); the opposite occurred for A. versicolor and P. verrucosum with 71% and 58% of STC and OTA detected in cheese rind, respectively. Available predictive models fitted fungal growth on the cheese rind well, but validation was not possible for mycotoxins because they were produced in a very narrow T range.
Role of FAD-I in Fusobacterial Interspecies Interaction and Biofilm Formation
Authors: Shokeen Bhumika , Park Jane , Duong Emily , Rambhia Sonam , Paul Manash , Weinberg Aaron , Shi Wenyuan , Lux Renate
Published: January 2020

RadD, a major adhesin of oral fusobacteria, is part of a four-gene operon encoding the small lipoprotein FAD-I and two currently uncharacterized small proteins encoded by the rapA and rapB genes. Previously, we described a role for FAD-I in the induction of human B-defensin 2 (hBD2) upon contact with oral epithelial cells. Here, we investigated potential roles for fad-I, rapA, and rapB in interspecies interaction and biofilm formation. Gene inactivation mutants were generated for each of these genes in the nucleatum and polymorphum subspecies of Fusobacterium nucleatum and characterized for their adherence to partner species, biofilm formation, and operon transcription. Binding to Streptococcus gordonii was increased in all mutant strains with Δfad-I having the most significant effect. This increased adherence was directly proportional to elevated radD transcript levels and resulted in significantly different architecture and height of the biofilms formed by Δfad-I and S. gordonii compared to the wild-type parent. In conclusion, FAD-I is important for fusobacterial interspecies interaction as its lack leads to increased production of the RadD adhesin suggesting a role of FAD-I in its regulation. This regulatory effect does not require the presence of functional RadD.
Thermal Disturbances in Permafrost Due to Open Pit Mining and Tailings Impoundment
Authors: Booshehrian Ahmad , Wan Richard , Su Grant
Published: January 2020

The paper is concerned with thermal disturbances in continuous permafrost due to open pit mining and tailings impoundment in the cold regions of Northern Canada. Numerical simulations were conducted to investigate issues of thermal regime changes and permafrost degradation in both the short term and the long term in connection with the proposed Kiggavik project in Nunavut, Canada. The results of numerical simulations indicate that no open talik would form below the East Zone and Center Zone pits during the estimated mining and milling operation period of 14 years, although a thin thawed zone would develop surrounding the open pits. For the Main Zone pit where the excavation would break through permafrost, the open talik remains following an extended operation period of 25 years with a 5 to 30 m thawed zone along the pit side walls. In the long term, with a plausible climate change scenario of 5 °C increase in the mean annual ground surface temperature during the next 100 years, the permafrost surrounding the in-pit tailings management facilities (TMFs) would reduce greatly in about 500 years. However, an approximately 40 m thick permafrost layer would remain on the top of the TMFs, which is impervious and would prevent any tailings pore water from migrating upward to reach the ground surface.
Parallel Simulation of Audio- and Radio-Magnetotelluric Data
Authors: Yavich Nikolay , Malovichko Mikhail , Shlykov Arseny
Published: January 2020

This paper presents a novel numerical method for simulation controlled-source audio-magnetotellurics (CSAMT) and radio-magnetotellurics (CSRMT) data. These methods are widely used in mineral exploration. Interpretation of the CSAMT and CSRMT data collected over an area with the complex geology requires application of effective methods of numerical modeling capable to represent the geoelectrical model of a deposit well. In this paper, we considered an approach to 3D electromagnetic (EM) modeling based on new types of preconditioned iterative solvers for finite-difference (FD) EM simulation. The first preconditioner used fast direct inversion of the layered Earth FD matrix (Green’s function preconditioner). The other combined the first with a contraction operator transformation. To illustrate the effectiveness of the developed numerical modeling methods, a 3D resistivity model of Aleksandrovka study area in Kaluga Region, Russia, was prepared based on drilling data, AMT, and a detailed CSRMT survey. We conducted parallel EM simulation of the full CSRMT survey. Our results indicated that the developed methods can be effectively used for modeling EM responses over a realistic complex geoelectrical model for a controlled source EM survey with hundreds of receiver stations. The contraction-operator preconditioner outperformed the Green’s function preconditioner by factor of 7–10, both with respect to run-time and iteration count, and even more at higher frequencies.
Automated Quantitative Mineralogy Applied to Metamorphic Rocks
Authors: Keulen Nynke , Malkki Sebastian Næsby , Graham Shaun
Published: January 2020

The ability to apply automated quantitative mineralogy (AQM) on metamorphic rocks was investigated on samples from the Fiskenæsset complex, Greenland. AQM provides the possibility to visualize and quantify microstructures, minerals, as well as the morphology and chemistry of the investigated samples. Here, we applied the ZEISS Mineralogic software platform as an AQM tool, which has integrated matrix corrections and full quantification of energy dispersive spectrometry data, and therefore is able to give detailed chemical information on each pixel in the AQM mineral maps. This has been applied to create mineral maps, element concentration maps, element ratio maps, mineral association maps, as well as to morphochemically classify individual minerals for their grain shape, size, and orientation. The visualization of metamorphic textures, while at the same time quantifying their textures, is the great strength of AQM and is an ideal tool to lift microscopy from the qualitative to the quantitative level.
Binding Properties of Mechanically Activated Nepheline Containing Mining Waste
Authors: Gurevich Basya I. , Kalinkina Elena V. , Kalinkin Alexander M.
Published: January 2020

The development of apatite and rare-metal deposits of the Khibiny and Lovozero—the world’s largest ultrabasic massifs located in the Kola Alkaline Province—is accompanied by accumulation of huge amounts of sandy tailings dumps, about half consisting of nepheline. These tailings, on the one hand, pose a real threat of environmental pollution. On the other hand, they are “technogenic deposits” that contain reserves of valuable components (Na2O, K2O, Al2O3, etc.). In this paper, methods of processing of the nepheline-containing mining waste using mechanical activation to produce binding materials—geopolymers and blended cements—are observed. The advantages of combining the nepheline containing tailings dumps with other mining wastes accumulated in the region, such as Cu–Ni slag, are presented.
Activity Dependence of a Novel Lectin Family on Structure and Carbohydrate-Binding Properties
Authors: Chikalovets Irina , Filshtein Alina , Molchanova Valentina , Mizgina Tatyana , Lukyanov Pavel , Nedashkovskaya Olga , Hua Kuo-Feng , Chernikov Oleg
Published: January 2020

A GalNAc/Gal-specific lectins named CGL and MTL were isolated and characterized from the edible mussels Crenomytilus grayanus and Mytilus trossulus. Amino acid sequence analysis of these lectins showed that they, together with another lectin MytiLec-1, formed a novel lectin family, adopting β-trefoil fold. In this mini review we discuss the structure, oligomerization, and carbohydrate-binding properties of a novel lectin family. We describe also the antibacterial, antifungal, and antiproliferative activities of these lectins and report about dependence of activities on molecular properties. Summarizing, CGL, MTL, and MytiLec-1 could be involved in the immunity in mollusks and may become a basis for the elaboration of new diagnostic tools or treatments for a variety of cancers.
Isolation and Characterization of a Novel Sialoglycopeptide Promoting Osteogenesis from Gadus morhua Eggs
Authors: Hei Zhiliang , Zhao Meihui , Tian Yingying , Chang Hong , Shen Xuanri , Xia Guanghua , Wang Jingfeng
Published: January 2020

Gadus morhua eggs contain several nutrients, including polyunsaturated fatty acids, lecithin and glycoproteins. A novel sialoglycopeptide from the eggs of G. morhua (Gm-SGPP) was extracted with 90% phenol and purified by Q Sepharose Fast Flow (QFF) ion exchange chromatography, followed by S-300 gel filtration chromatography. Gm-SGPP contained 63.7% carbohydrate, 16.2% protein and 18.6% N-acetylneuraminic acid. High-performance size exclusion chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) demonstrated that Gm-SGPP is a 7000-Da pure sialoglycopeptide. β-elimination reaction suggested that Gm-SGPP contained N-glycan units. Amino acid N-terminal sequence analysis indicated the presence of Ala-Ser-Asn-Gly-Thr-Gln-Ala-Pro amino acid sequence. Moreover, N-glycan was connected at the third Asn location of the peptide chain through GlcNAc. Gm-SGPP was composed of D-mannose, D-glucuronic acid and D-galactose. Fourier transform-infrared spectroscopy (FT-IR), 1H-nuclear magnetic resonance spectroscopy (1H-NMR) and methylation analysis were performed to reveal the structure profile of Gm-SGPP. In vitro results showed that the proliferation activity of MC3T3-E1 cells was significantly promoted by Gm-SGPP. In vivo data revealed that Gm-SGPP increased the calcium and phosphorus content of tibias and promoted longitudinal bone growth in adolescent rats.
Lignans and Their Derivatives from Plants as Antivirals
Authors: Cui Qinghua , Du Ruikun , Liu Miaomiao , Rong Lijun
Published: January 2020

Lignans are widely produced by various plant species; they are a class of natural products that share structural similarity. They usually contain a core scaffold that is formed by two or more phenylpropanoid units. Lignans possess diverse pharmacological properties, including their antiviral activities that have been reported in recent years. This review discusses the distribution of lignans in nature according to their structural classification, and it provides a comprehensive summary of their antiviral activities. Among them, two types of antiviral lignans—podophyllotoxin and bicyclol, which are used to treat venereal warts and chronic hepatitis B (CHB) in clinical, serve as examples of using lignans for antivirals—are discussed in some detail. Prospects of lignans in antiviral drug discovery are also discussed.
Quercetin Exerts Age-Dependent Beneficial Effects on Blood Pressure and Vascular Function, But Is Inefficient in Preventing Myocardial Ischemia-Reperfusion Injury in Zucker Diabetic Fatty Rats
Authors: Ferenczyova Kristina , Kalocayova Barbora , Kindernay Lucia , Jelemensky Marek , Balis Peter , Berenyiova Andrea , Zemancikova Anna , Farkasova Veronika , Sykora Matus , Tothova Lubomira , Jasenovec Tomas , Radosinska Jana , Torok Jozef , Cacanyiova Sona , Barancik Miroslav , Bartekova Monika
Published: January 2020

Background: Quercetin (QCT) was shown to exert beneficial cardiovascular effects in young healthy animals. The aim of the present study was to determine cardiovascular benefits of QCT in older, 6-month and 1-year-old Zucker diabetic fatty (ZDF) rats (model of type 2 diabetes). Methods: Lean (fa/+) and obese (fa/fa) ZDF rats of both ages were treated with QCT for 6 weeks (20 mg/kg/day). Isolated hearts were exposed to ischemia-reperfusion (I/R) injury (30 min/2 h). Endothelium-dependent vascular relaxation was measured in isolated aortas. Expression of selected proteins in heart tissue was detected by Western blotting. Results: QCT reduced systolic blood pressure in both lean and obese 6-month-old rats but had no effect in 1-year-old rats. Diabetes worsened vascular relaxation in both ages. QCT improved vascular relaxation in 6-month-old but worsened in 1-year-old obese rats and had no impact in lean controls of both ages. QCT did not exert cardioprotective effects against I/R injury and even worsened post-ischemic recovery in 1-year-old hearts. QCT up-regulated expression of eNOS in younger and PKCε expression in older rats but did not activate whole PI3K/Akt pathway. Conclusions: QCT might be beneficial for vascular function in diabetes type 2; however, increasing age and/or progression of diabetes may confound its vasculoprotective effects. QCT seems to be inefficient in preventing myocardial I/R injury in type 2 diabetes and/or higher age. Impaired activation of PI3K/Akt kinase pathway might be, at least in part, responsible for failing cardioprotection in these subjects.
Ginsenoside Re Mitigates 6-Hydroxydopamine-Induced Oxidative Stress through Upregulation of GPX4
Authors: Lee Gyeong Hee , Lee Won Jin , Hur Jinwoo , Kim Eunsu , Lee Hyuk Gyoon , Seo Han Geuk
Published: January 2020

Ginsenosides are active components found abundantly in ginseng which has been used as a medicinal herb to modify disease status for thousands of years. However, the pharmacological activity of ginsenoside Re in the neuronal system remains to be elucidated. Neuroprotective activity of ginsenoside Re was investigated in SH-SY5Y cells exposed to 6-hydroxydopamine (6-OHDA) to induce cellular injury. Ginsenoside Re significantly inhibited 6-OHDA-triggered cellular damage as judged by analysis of tetrazolium dye reduction and lactose dehydrogenase release. In addition, ginsenoside Re induced the expression of the antioxidant protein glutathione peroxidase 4 (GPX4) but not catalase, glutathione peroxidase 1, glutathione reductase, or superoxide dismutase-1. Furthermore, upregulation of GPX4 by ginsenoside Re was mediated by phosphoinositide 3-kinase and extracellular signal-regulated kinase but not by p38 mitogen-activated protein kinase or c-Jun N-terminal kinase. Ginsenoside Re also suppressed 6-OHDA-triggered cellular accumulation of reactive oxygen species and peroxidation of membrane lipids. The GPX4 inhibitor (1S,3R)-RSL3 reversed ginsenoside Re-mediated inhibition of cellular damage in SH-SY5Y cells exposed to 6-OHDA, indicating that the neuronal activity of ginsenoside Re is due to upregulation of GPX4. These findings suggest that ginsenoside Re-dependent upregulation of GPX4 reduces oxidative stress and thereby alleviates 6-OHDA-induced neuronal damage.
Inhibition of TGF-β Signaling in Gliomas by the Flavonoid Diosmetin Isolated from Dracocephalum peregrinum L.
Authors: Yan Yuli , Liu Xingyu , Gao Jie , Wu Yin , Li Yuxin
Published: January 2020

Background: Dracocephalum peregrinum L., a traditional Kazakh medicine, has good expectorant, anti-cough, and to some degree, anti-asthmatic effects. Diosmetin (3′,5,7-trihydroxy-4′-methoxyflavone), a natural flavonoid found in traditional Chinese herbs, is the main flavonoid in D. peregrinum L. and has been used in various medicinal products because of its anticancer, antimicrobial, antioxidant, estrogenic, and anti-inflammatory effects. The present study aimed to investigate the effects of diosmetin on the proliferation, invasion, and migration of glioma cells, as well as the possible underlying mechanisms. Methods: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), scratch wound, and Transwell assays were used to demonstrate the effects of diosmetin in glioma. Protein levels of Bcl-2, Bax, cleaved caspase-3, transforming growth factor-β (TGF-β), E-cadherin, and phosphorylated and unphosphorylated smad2 and smad3 were determined by Western blots. U251 glioma cell development and progression were measured in vivo in a mouse model. Results: Diosmetin inhibited U251 cell proliferation, migration, and invasion in vitro, the TGF-β signaling pathway, and Bcl-2 expression. In contrast, there was a significant increase in E-cadherin, Bax, and cleaved caspase-3 expression. Furthermore, it effectively reduced the tumorigenicity of glioma cells and promoted apoptosis in vivo. Conclusion: The results of this study suggest that diosmetin suppresses the growth of glioma cells in vitro and in vivo, possibly by activating E-cadherin expression and inhibiting the TGF-β signaling pathway.
Remarkable Alkene-to-Alkene and Alkene-to-Alkyne Transfer Reactions of Selenium Dibromide and PhSeBr. Stereoselective Addition of Selenium Dihalides to Cycloalkenes
Authors: Potapov Vladimir A. , Musalov Maxim V. , Kurkutov Evgeny O. , Yakimov Vladimir A. , Khabibulina Alfiya G. , Musalova Maria V. , Amosova Svetlana V. , Borodina Tatyana N. , Albanov Alexander I.
Published: January 2020

The original goal of this research was to study stereochemistry of selenium dihalides addition to cycloalkenes and properties of obtained products. Remarkable alkene-to-alkene and alkene-to-alkyne transfer reactions of selenium dibromide and PhSeBr were discovered during this research. The adducts of selenium dibromide with alkenes or cycloalkenes easily exchange SeBr2 with other unsaturated compounds, including acetylenes, at room temperature, in acetonitrile. Similar alkene-to-alkene and alkene-to-alkyne transfer reactions of the PhSeBr adducts with alkenes or cycloalkenes take place. The supposed reaction pathway includes the selenium group transfer from seleniranium species to alkenes or alkynes. It was found that the efficient SeBr2 and PhSeBr transfer reagents are Se(CH2CH2Br)2 and PhSeCH2CH2Br, which liberate ethylene, leading to a shift in equilibrium. The regioselective and stereoselective synthesis of bis(E-2-bromovinyl) selenides and unsymmetrical E-2-bromovinyl selenides was developed based on the SeBr2 and PhSeBr transfer reactions which proceeded with higher selectivity compared to analogous addition reactions of SeBr2 and PhSeBr to alkynes under the same conditions.
Nor-Lignans: Occurrence in Plants and Biological Activities—A Review
Authors: Frezza Claudio , Venditti Alessandro , Toniolo Chiara , De Vita Daniela , Franceschin Marco , Ventrone Antonio , Tomassini Lamberto , Foddai Sebastiano , Guiso Marcella , Nicoletti Marcello , Serafini Mauro , Bianco Armandodoriano
Published: January 2020

In this review article, the occurrence of nor-lignans and their biological activities are explored and described. Nor-lignans have proven to be present in several different families also belonging to chemosystematically distant orders as well as to have many different beneficial pharmacological activities. This review article represents the first one on this argument and is thought to give a first overview on these compounds with the hope that their study may continue and increase, after this.
Supercritical CO2 Extraction of Extracted Oil from Pistacia lentiscus L.: Mathematical Modeling, Economic Evaluation and Scale-Up
Authors: Aydi Abdelkarim , Zibetti André Wüst , Al-Khazaal Abdulaal Z. , ELADEB Aboulbaba , ADBERRABA Manef , BARTH Danielle
Published: January 2020

In this study, the extracted oil of Pistacia lentiscus L. the Tunis region was extracted using supercritical carbon dioxide (SC-CO2) extraction containing different major components in the oil such as α-pinene (32%) and terpinene-4-ol (13%). The investigation of the effect of different variables on the extraction yield with 5% level of confidence interval showed that the CO2 pressure was the main significant variable to influence the oil yield. In order to better understand the phenomena, three parameters were considered to adjust all parameters of broken and intact cell (BIC) model: grinding efficiency (G), the internal mass transfer parameter ( k S a 0 ), and the external mass transfer parameter ( k f a 0 ), which were estimated by experimental extraction curves to calculate the diffusion coefficient. From an economic point of view, we found out that the high cost of production of the extracted oil was due to the low mass of extracted oil obtained from this type of plant.
Design, Synthesis, and In Vitro Evaluation of Benzofuro[3,2-c]Quinoline Derivatives as Potential Antileukemia Agents
Authors: Lin Ying , Xing Dong , Wu Wen-Biao , Xu Gao-Ya , Yu Li-Fang , Tang Jie , Zhou Yu-Bo , Li Jia , Yang Fan
Published: January 2020

Herein, we design and synthesize an array of benzofuro[3,2-c]quinolines starting from 3-(2-methoxyphenyl)quinolin-4(1H)ones via a sequential chlorination/demethylation, intramolecular cyclization pathway. This sequential transformation was efficient, conducted under metal-free and mild reaction conditions, and yielded corresponding benzofuro[3,2-c]quinolines in high yields. In vitro biological evaluation indicated that such type of compounds showed excellent antileukemia activity and selectivity, and therefore may offer a promising hit compound for developing antileukemia compounds.
The Trichoderma atroviride Strains P1 and IMI 206040 Differ in Their Light-Response and VOC Production
Authors: Speckbacher Verena , Ruzsanyi Veronika , Wigger Modestus , Zeilinger Susanne
Published: January 2020

Trichoderma atroviride is a strong necrotrophic mycoparasite antagonizing and feeding on a broad range of fungal phytopathogens. It further beneficially acts on plants by enhancing growth in root and shoot and inducing systemic resistance. Volatile organic compounds (VOCs) are playing a major role in all those processes. Light is an important modulator of secondary metabolite biosynthesis, but its influence has often been neglected in research on fungal volatiles. To date, T. atroviride IMI 206040 and T. atroviride P1 are among the most frequently studied T. atroviride strains and hence are used as model organisms to study mycoparasitism and photoconidiation. However, there are no studies available, which systematically and comparatively analyzed putative differences between these strains regarding their light-dependent behavior and VOC biosynthesis. We therefore explored the influence of light on conidiation and the mycoparasitic interaction as well as the light-dependent production of VOCs in both strains. Our data show that in contrast to T. atroviride IMI 206040 conidiation in strain P1 is independent of light. Furthermore, significant strain- and light-dependent differences in the production of several VOCs between the two strains became evident, indicating that T. atroviride P1 could be a better candidate for plant protection than IMI 206040.
Synthesis of Monolayer MoSe2 with Controlled Nucleation via Reverse-Flow Chemical Vapor Deposition
Authors: Wang Siyuan , Wang Guang , Yang Xi , Yang Hang , Zhu Mengjian , Zhang Sen , Peng Gang , Li Zheng
Published: January 2020

Two-dimensional (2D) layered semiconductor materials, such as transition metal dichalcogenides (TMDCs), have attracted considerable interests because of their intriguing optical and electronic properties. Controlled growth of TMDC crystals with large grain size and atomically smooth surface is indeed desirable but remains challenging due to excessive nucleation. Here, we have synthesized high-quality monolayer, bilayer MoSe2 triangular crystals, and continuous thin films with controlled nucleation density via reverse-flow chemical vapor deposition (CVD). High crystallinity and good saturated absorption performance of MoSe2 have been systematically investigated and carefully demonstrated. Optimized nucleation and uniform morphology could be achieved via fine-tuning reverse-flow switching time, growth time and temperature, with corresponding growth kinetics proposed. Our work opens up a new approach for controllable synthesis of monolayer TMDC crystals with high yield and reliability, which promote surface/interface engineering of 2D semiconductors towards van der Waals heterostructure device applications.
Facile and Green Fabrication of Carrageenan-Silver Nanoparticles for Colorimetric Determination of Cu2+ and S2−
Authors: Wang Yesheng , Dong Xueyi , Zhao Li , Xue Yun , Zhao Xihui , Li Qun , Xia Yanzhi
Published: January 2020

In the present work, silver nanoparticles (AgNPs) were prepared by a simple and green method using carrageenan as reducing and capping agent. The as-synthesized carrageenan-AgNPs was demonstrated as an effective duel colorimetric sensing for selective and sensitive recognition of Cu2+ and S2−, which could be used to detect these ions with naked eyes. In addition, the possible sensing mechanism was that Cu2+ ions caused serious aggregation of carrageenan-AgNPs, which led to the color change of carrageenan-AgNPs. AgNPs were etched by S2− forming Ag2S, which played an important role in the determination of S2− ions. Furthermore, it has been successfully applied to the determination of Cu2+ and S2− in tap water and lake water, showing its great potential for the analysis of environmental water samples.
The Influence of Synthesis Parameters on Structural and Magnetic Properties of Iron Oxide Nanomaterials
Authors: Cursaru Laura Madalina , Piticescu Roxana Mioara , Dragut Dumitru Valentin , Tudor Ioan Albert , Kuncser Victor , Iacob Nicusor , Stoiciu Florentin
Published: January 2020

Magnetic iron oxides have been used in biomedical applications, such as contrast agents for magnetic resonance imaging, carriers for controlled drug delivery and immunoassays, or magnetic hyperthermia for the past 40 years. Our aim is to investigate the effect of pressure and temperature on the structural, thermal, and magnetic properties of iron oxides prepared by hydrothermal synthesis at temperatures of 100–200 °C and pressures of 20–1000 bar. It has been found that pressure influences the type of iron oxide crystalline phase. Thus, the results obtained by Mössbauer characterization are in excellent agreement with X-ray diffraction and optical microscopy characterization, showing that, for lower pressure values (<100 bar), hematite is formed, while, at pressures >100 bar, the major crystalline phase is goethite. In addition, thermal analysis results are consistent with particle size analysis by X-ray diffraction, confirming the crystallization of the synthesized iron oxides. One order of magnitude higher magnetization has been obtained for sample synthesized at 1000 bar. The same sample provides after annealing treatment, the highest amount of good quality magnetite leading to a magnetization at saturation of 30 emu/g and a coercive field of 1000 Oe at 10 K and 450 Oe at 300 K, convenient for various applications.
Dual pH- and GSH-Responsive Degradable PEGylated Graphene Quantum Dot-Based Nanoparticles for Enhanced HER2-Positive Breast Cancer Therapy
Authors: Ko Na Re , Van Se Young , Hong Sung Hwa , Kim Seog-Young , Kim Miran , Lee Jae Seo , Lee Sang Ju , Lee Yong-kyu , Kwon Il Keun , Oh Seung Jun
Published: January 2020

Dual stimuli-responsive degradable carbon-based nanoparticles (DS-CNPs) conjugated with Herceptin (HER) and polyethylene glycol (PEG) have been designed for the treatment of HER2-positive breast cancer. Each component has been linked through disulfide linkages that are sensitive to glutathione in a cancer microenvironment. β-cyclodextrin (β-CD) on the surface of DS-CNPs formed an inclusion complex (DL-CNPs) with doxorubicin (DOX) at a high loading capacity of 5.3 ± 0.4%. In response to a high level of glutathione (GSH) and low pH in a tumor environment, DL-CNPs were rapidly degraded and released DOX in a controlled manner via disruption of host–guest inclusion. These novel DL-CNPs exhibited high cellular uptake with low toxicity, which induced the efficient inhibition of antitumor activity both in vitro and in vivo. Cell viability, confocal laser scanning microscopy, and animal studies indicate that DL-CNPs are a great platform with a synergistically enhanced antitumor effect from the dual delivery of HER and DOX in DL-CNPs.
Microwave Synthesis of Gold Nanoclusters with Garlic Extract Modifications for the Simple and Sensitive Detection of Lead Ions
Authors: Ryavanaki Lingaraj , Tsai Hweiyan , Fuh C. Bor
Published: January 2020

Novel bovine serum albumin (BSA)-gold nanoclusters with garlic extract modifications (mw_G-BSA-AuNCs) were prepared through microwave-assisted rapid synthesis. The modified nanoclusters were characterized and used for the simple and sensitive detection of Pb2+ ions. Both turn-on and turn-off methods were used and compared for Pb2+ ion detection. For Pb2+ ions, the preparation time for the modified nanoclusters was 10 min, and the detection time for the nanoclusters was 6 min. The modified nanoclusters were stable, and their fluorescence intensities changed by less than 10% in 60 days. The detection limit and linear range for the “off-on” method of mw_G-BSA-AuNCs for Pb2+ ion detection were 0.28 and 1–20 nM, respectively. The recoveries of the mw_G-BSA-AuNCs probe used for the detection of the Pb(II) ion in tap water ranged from 93.8% to 102.2%, with an average of 97.1%. The “off-on” method of mw_G-BSA-AuNCs can provide a lower detection limit, higher selectivity, and better recovery than the commonly used “turn-off” methods of mw_BSA-AuNCs for Pb2+ ion detection. The proposed method is superior to other methods proposed from 2018 to 2019 because it can provide a shorter preparation time and a lower detection limit with good selectivity. The microwave-assisted novel compound, mw_G-BSA-AuNCs, can be rapidly synthesized in a green manner and can provide a low detection limit, good selectivity, and a simple and fast reaction for Pb2+ ion detection.
High Quality Factor, High Sensitivity Metamaterial Graphene—Perfect Absorber Based on Critical Coupling Theory and Impedance Matching
Authors: Cen Chunlian , Chen Zeqiang , Xu Danyang , Jiang Liying , Chen Xifang , Yi Zao , Wu Pinghui , Li Gongfa , Yi Yougen
Published: January 2020

By means of critical coupling and impedance matching theory, we have numerically simulated the perfect absorption of monolayer graphene. Through the critical coupling effect and impedance matching, we studied a perfect single-band absorption of the monolayer graphene and obtained high quality factor (Q-factor = 664.2) absorption spectrum which has an absorbance close to 100% in the near infrared region. The position of the absorption spectrum can be adjusted by changing the ratio between the radii of the elliptic cylinder air hole and the structural period. The sensitivity of the absorber can be achieved S = 342.7 nm/RIU (RIU is the per refractive index unit) and FOM = 199.2 (FOM is the figure of merit), which has great potential for development on biosensors. We believe that our research will have good application prospects in graphene photonic devices and optoelectronic devices.
Comparison of the Pathogenicity of Two Different Branches of Senecavirus a Strain in China
Authors: Zhang Huawei , Chen Pin , Hao Genxi , Liu Wenqiang , Chen Huanchun , Qian Ping , Li Xiangmin
Published: January 2020

Senecavirus A (SVA), an emerging infectious disease, is associated with the porcine idiopathic vesicular disease. Here, the pathogenesis of different strains of SVA was investigated in growing-finishing pigs. We aimed to evaluate the replication characteristics, virus particle morphology, clinical signs, and vesicular lesions in comparison with two different strains of SVA. The animals were infected with SVA HB-CH-2016 or CH/AH-02/2017 by intranasal routes (3 mL, 109TCID50/mL) and monitored daily for 14 days post-inoculation (dpi) for clinical signs and vesicular lesions. Viremia or viral shedding was detected in the blood, fecal swab, and nasal swab samples. Results showed no distinct differences in plaque size, replication ability, and characteristic virions between SVA HB-CH-2016 and CH/AH-02/2017 strains. Animal experimental results showed that both SVA CH/AH-02/2017 and SVA HB-CH-2016 could infect pigs. However, an obvious difference in the pathogenicity and dynamics of infection was observed between SVA HB-CH-2016 and CH/AH-02/2017 strains. The pathogenesis of SVA CH/AH-02/2017 was similar to that of published results of USA strains, whereas the SVA HB-CH-2016 strain had low pathogenicity to pigs. Clinical signs and vesicular lesions were observed in SVA CH/AH-02/2017-infected pigs. Additionally, the different branches of SVA should be capable of inducing broad cross-reactive neutralizing antibodies, which play an important role in clearing the SVA virus. This study of animal models for SVA infection will be beneficial to develop vaccines and antivirals.
Lipid Systems for the Delivery of Amphotericin B in Antifungal Therapy
Authors: Faustino Célia , Pinheiro Lídia
Published: January 2020

Amphotericin B (AmB), a broad-spectrum polyene antibiotic in the clinic for more than fifty years, remains the gold standard in the treatment of life-threatening invasive fungal infections and visceral leishmaniasis. Due to its poor water solubility and membrane permeability, AmB is conventionally formulated with deoxycholate as a micellar suspension for intravenous administration, but severe infusion-related side effects and nephrotoxicity hamper its therapeutic potential. Lipid-based formulations, such as liposomal AmB, have been developed which significantly reduce the toxic side effects of the drug. However, their high cost and the need for parenteral administration limit their widespread use. Therefore, delivery systems that can retain or even enhance antimicrobial efficacy while simultaneously reducing AmB adverse events are an active area of research. Among those, lipid systems have been extensively investigated due to the high affinity of AmB for binding lipids. The development of a safe and cost-effective oral formulation able to improve drug accessibility would be a major breakthrough, and several lipid systems for the oral delivery of AmB are currently under development. This review summarizes recent advances in lipid-based systems for targeted delivery of AmB focusing on non-parenteral nanoparticulate formulations mainly investigated over the last five years and highlighting those that are currently in clinical trials.
CMOS-Compatible Measures for Thermal Management of Phase-Sensitive Silicon Photonic Systems
Authors: Krochin-Yepez Pedro-Andrei , Scholz Ulrike , Zimmermann Andre
Published: January 2020

To date, several photonic applications have been demonstrated without considerable thermal management efforts. However, in phase-sensitive photonic applications, thermal management becomes of utmost importance. Thermal management of photonic systems requires not only efficient heat dissipation, but also reduction of on-chip temperature gradients. Particularly in highly integrated systems, in which several components are integrated within a single photonic integrated circuit, the reduction of on-chip temperature gradients is necessary to guarantee the correct functionality of the system. Due to their high integration density as well as their extreme temperature sensitivity, optical phased arrays are ideal examples of a system, where thermal management is required. Ideally, thermal management solutions of such systems should not require additional power for operation. Therefore, it is desired to improve the heat dissipation and to reduce temperature gradients by structural modifications of the photonic circuit. Furthermore, to cope with the advantages of silicon photonics, thermal management solutions must be compatible with series fabrication processes. In this work, complementary metal–oxide–semiconductor (CMOS)-compatible measures for thermal management of silicon photonic integrated circuits are proposed and validated by characterization of in-house fabricated thermal demonstrators. The proposed concepts are extremely efficient not only in reducing temperature gradients, but also in improving the heat dissipation from integrated heat sources.
Sustainability Perspectives of Vigna unguiculata L. Walp. Cultivation under No Tillage and Water Stress Conditions
Authors: Guzzetti Lorenzo , Fiorini Andrea , Panzeri Davide , Tommasi Nicola , Grassi Fabrizio , Taskin Eren , Misci Chiara , Puglisi Edoardo , Tabaglio Vincenzo , Galimberti Andrea , Labra Massimo
Published: January 2020

Nowadays, agriculture is facing the great challenge of climate change which puts the productivity of the crops in peril due to unpredictable rain patterns and water shortages, especially in the developing world. Besides productivity, nutritional values of the yields of these crops may also be affected, especially under low mechanization and the low water availability conditions of the developing world. Conservation agriculture (CA) is a topic of emerging interest due to the provision of adequate yields and reduced environmental impact, such as greenhouse gas emissions, by being based on three main principles: minimum soil disturbance (reduced or no tillage), cover crop maintenance, and crop rotation. The aim of this study was to assess the impact of CA management on the growth performance and the nutritional profile of cowpea (Vigna unguiculata L. Walp), a pulse of African origin, commonly known as black eye bean under field conditions. A field experiment was designed to assess the effect of conventional tillage (CT) and no-tillage (NT) combined with the usage of a set of cover crops, coupled to normal and deficient water regimes. Cowpea was revealed to be able to grow and yield comparably at each level of the treatment tested, with a better ability to face water exhaustion under CA management. After a faster initial growth phase in CT plots, the level of adaptability of this legume to NT was such that growth performances improved significantly with respect to CT plots. The flowering rate was higher and earlier in CT conditions, while in NT it was slower but longer-lasting. The leafy photosynthetic rate and the nutritional profile of beans were slightly influenced by tillage management: only total starch content was negatively affected in NT and watered plots while proteins and aminoacids did not show any significant variation. Furthermore, significantly higher carbon and nitrogen concentration occurred in NT soils especially at the topmost (0–5 cm) soil horizon. These findings confirm the capability of CA to enrich soil superficial horizons and highlight that cowpea is a suitable crop to be grown under sustainable CA management. This practice could be pivotal to preserve soils and to save agronomical costs without losing a panel of nutrients that are important to the human diet. Due to its great protein and aminoacidic composition, V. unguiculata is a good candidate for further cultivation in regions of the word facing deficiencies in the intake of such nutrients, such as the Mediterranean basins and Sub-Saharan countries.
Effects of Light and Daytime on the Regulation of Chitosan-Induced Stomatal Responses and Defence in Tomato Plants
Authors: Czékus Zalán , Poór Péter , Tari Irma , Ördög Attila
Published: January 2020

Closure of stomata upon pathogenesis is among the earliest plant immune responses. However, our knowledge is very limited about the dependency of plant defence responses to chitosan (CHT) on external factors (e.g., time of the day, presence, or absence of light) in intact plants. CHT induced stomatal closure before dark/light transition in leaves treated at 17:00 hrs and stomata were closed at 09:00 hrs in plants treated at dawn and in the morning. CHT was able to induce generation of reactive oxygen species (ROS) in guard cells in the first part of the light phase, but significant nitric oxide production was observable only at 15:00 hrs. The actual quantum yield of PSII electron transport (ΦPSII) decreased upon CHT treatments at 09:00 hrs in guard cells but it declined only at dawn in mesophyll cells after the treatment at 17:00 hrs. Expression of Pathogenesis-related 1 (PR1) and Ethylene Response Factor 1 were already increased at dawn in the CHT-treated leaves but PR1 expression was inhibited in the dark. CHT-induced systemic response was also observed in the distal leaves of CHT-treated ones. Our results suggest a delayed and daytime-dependent defence response of tomato plants after CHT treatment at night and under darkness.