bluuebunny/crossref_metadata_2025 huggingface dataset:
Whose Line is it Anyway? Using MBSE in the Management and Acceptance of the Defence Lines of Development
Authors: Dent Matthew , Shield Simon , Reeves Andy , Royston Jamie
Published: August 2017

As we continue to apply Systems Engineering and Model Based Approaches to the acquisition of complex and closely coupled systems, the ability to map, analyse and manage the interfaces across all the component elements of a capability presents a significant challenge. This paper provides an overview of the application of a Model Based Systems Engineering Approach to a case study, supported by the Whole‐of‐System Analytical Framework (WSAF), to manage the integration and acceptance of the Defence Lines of Development (DLOD) and its application to a case study in the United Kingdom (UK) defence acquisition domain. The approach seeks to provide the ability to conduct analysis of DLOD elements down to a significant level of granularity, including the inter‐ and intra‐DLOD dependencies. The aim being to provide a comprehensive, consistent and systematic view of the DLODs across a complex and disparate stakeholder landscape. This supports the ability to manage the integration and acceptance of the DLODs which, when successfully effected, deliver military capability.
A Case Study of Systems Engineering Implementation in Designing Electronic Blast Systems
Authors: Whyte Aldaine , Erasmus Louwrence
Published: August 2017

It is not known if a lack of formal system engineering processes being used in the design and development of new and existing systems, lead to high risk of failure in the implementation of electronic blast systems. In mining, more specifically electronic blast systems, minimal research exists on the application of system engineering principles and practices to deliver better systems faster, and more cost‐effectively compared to that of ad‐hoc, non‐systemic approaches. The main objective of the research was to determine how well system engineering processes are applied in electronic blast systems implementation. The investigations showed results of the measurement through the SECM models and revealed that the company is on maturity level of 2 with aspects of level 3 in all three focus‐area categories, namely technical, management and environment. The activities performed indicate that SECM outputs are managed to a plan, and there are some defined organisation processes used to plan and execute activities. System engineering processes do exist but are informal, and most are not measured, and this prevents process improvement, and hence an increase SECM maturity level.
Reverse Engineering Risk: Converging Medical Standards for Improved Systems Engineering
Authors: Fomin Pavel , Scheible William G. , Guillaume‐Joseph Gina
Published: August 2017

Early systems engineering and active risk management have been credited with improving the Department of Defence's (DoD) ability to deliver on cost, schedule, and technical requirements. The Government Accountability Office (GAO) continues to identify risk management of critical technologies as a key contributor in schedule delays and cost overruns. A review by GAO of key DoD programs has found that specifically an increase in technical scope, interoperability requirements, and advanced technology integration has been the root cause for many of these delays. To address these findings, DoD mandates Technology Risk Assessments (TRA) of key technologies at specific milestone gates. Unfortunately, the tools and metrics supplied for the TRAs continue to rely on dated concepts that have failed to provide the objective insight into modern technology integration and interoperability requirements. This paper proposes a new approach for technical risk management that borrows from concepts in the medical field that treat risk management as a top‐down integrated system concept.
Model‐Based Systems Engineering Pathfinder: Informing the Next Steps
Authors: Weiland Karen J. , Holladay Jon
Published: August 2017

In 2016, the NASA Engineering and Safety Center established a model‐based systems engineering (MBSE) Pathfinder. The primary motivations for establishing the MBSE Pathfinder were to advance the Agency's applications of MBSE and capture lessons‐learned to inform the next steps. The MBSE Pathfinder had four teams working in parallel for eight months on different topics of interest to NASA. The teams were encouraged to learn, and use creativity and innovation in their system modeling. The results were captured via reports, webinars, and a knowledge capture meeting. The approach taken for the MBSE Pathfinder was very successful in providing a number of lessons‐learned for NASA and for other organizations considering MBSE or pathfinder efforts, and in building a very strong and collaborative user community.
Organizational Capabilities in a Government R&D Enterprise
Authors: Griego Regina M. , Craft Richard L.
Published: August 2017

There are unique challenges to developing organizational capability in government R&D organizations that support specialized national missions. The complex nature of developing capabilities in these organizations is highlighted and research questions and challenges are posed. In particular, two broad challenges identified in this paper – 1) being able to understand the enterprise well enough to identify likely impacts of contemplated decisions and 2) being able to coordinate planning and decision making amongst stakeholders across the enterprise – are explored. Systems engineering literature is used as the basis for exploring the challenges from multiple perspectives. The intention of this paper is to provide an adequate description of the challenges, discuss some strategies that have been tried or proposed, and engage in a dialogue with the systems engineering community about other experiences in addressing the complexity of managing and evolving government R&D capability.
Worlds of Inclusion: Challenging Reading, Writing, and Publishing Science Fiction– and Fantasy‐Based Young Adult Literature
Authors: Garcia Antero
Published: August 2017

This forum reviews high‐interest young adult literature and adult texts. Exploring both print‐based and multimodal works, this column considers all kinds of texts that are encountered by contemporary readers, considering how the texts challenge and are challenged by readers.
Relationship between peroxisome proliferator‐activated receptor alpha activity and cellular concentration of 14 perfluoroalkyl substances in HepG2 cells
Authors: Rosenmai Anna Kjerstine , Ahrens Lutz , le Godec Théo , Lundqvist Johan , Oskarsson Agneta
Published: August 2017

Peroxisome proliferator‐activated receptor alpha (PPARα) is a molecular target for perfluoroalkyl substances (PFASs). Little is known about the cellular uptake of PFASs and how it affects the PPARα activity. We investigated the relationship between PPARα activity and cellular concentration in HepG2 cells of 14 PFASs, including perfluoroalkyl carboxylates (PFCAs), perfluoroalkyl sulfonates and perfluorooctane sulfonamide (FOSA). Cellular concentrations were determined by high‐performance liquid chromatography–tandem mass spectrometry and PPARα activity was determined in transiently transfected cells by reporter gene assay. Cellular uptake of the PFASs was low (0.04–4.1%) with absolute cellular concentrations in the range 4–2500 ng mg−1 protein. Cellular concentration of PFCAs increased with perfluorocarbon chain length up to perfluorododecanoate. PPARα activity of PFCAs increased with chain length up to perfluorooctanoate. The maximum induction of PPARα activity was similar for short‐chain (perfluorobutanoate and perfluoropentanoate) and long‐chain PFCAs (perfluorododecanoate and perfluorotetradecanoate) (approximately twofold). However, PPARα activities were induced at lower cellular concentrations for the short‐chain homologs compared to the long‐chain homologs. Perfluorohexanoate, perfluoroheptanoate, perfluorooctanoate, perfluorononanoate (PFNA) and perfluorodecanoate induced PPARα activities >2.5‐fold compared to controls. The concentration–response relationships were positive for all the tested compounds, except perfluorooctane sulfonate PFOS and FOSA, and were compound‐specific, as demonstrated by differences in the estimated slopes. The relationships were steeper for PFCAs with chain lengths up to and including PFNA than for the other studied PFASs. To our knowledge, this is the first report establishing relationships between PPARα activity and cellular concentration of a broad range of PFASs.
Development of high strength siloxane poly(urethane‐urea) elastomers based on linked macrodiols for heart valve application
Authors: Dandeniyage Loshini S. , Gunatillake Pathiraja A. , Adhikari Raju , Bown Mark , Shanks Robert , Adhikari Benu
Published: August 2017

Mixed macrodiol based siloxane poly(urethane‐urea)s (SiPUU) having number average molecular weights in the range 87–129 kDa/mol were synthesized to give elastomers with high tensile and tear strengths required to fabricate artificial heart valves. Polar functional groups were introduced into the soft segment to improve the poor segmental compatibility of siloxane polyurethanes. This was achieved by linking α,ω‐bis(6‐hydroxyethoxypropyl) poly(dimethylsiloxane) (PDMS) or poly(hexamethylene oxide) (PHMO) macrodiols with either 4,4′‐methylenediphenyl diisocyanate (MDI), hexamethylene diisocyanate (HDI) or isophorone diisocyanate (IPDI) prior to polyurethane synthesis. The hard segment was composed of MDI, and a 1:1 mixture of 1,3‐bis(4‐hydroxybutyl)‐1,1,3,3‐tetramethyldisiloxane and 1,2‐ethylene diamine. We report the effect of urethane linkers in soft segments on properties of the SiPUU. PHMO linked with either MDI or IPDI produced SiPUU with the highest tensile and tear strengths. Linking PDMS hardly affected the tensile strength; however, the tear strength was improved. The stress‐strain curves showed no plastic deformation region typically observed for conventional polyurethanes indicating good creep resistance. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1712–1720, 2018.
miR‐377‐3p drives malignancy characteristics via upregulating GSK‐3β expression and activating NF‐κB pathway in hCRC cells
Authors: Liu Wei‐Ying , Yang Zhen , Sun Qi , Yang Xi , Hu Yang , Xie Hong , Gao Hui‐Jie , Guo Li‐Ming , Yi Jian‐Ying , Liu Min , Tang Hua
Published: August 2017

MicroRNA (miRNA) dysregulation has been associated with carcinogenesis in many cancers, including human colorectal cancer (hCRC). However, the effect and mechanism of miR‐377‐3p on CRC remains elusive. Herein, we first found that miR‐377‐3p was upregulated in CRC tissues and promoted tumorigenic activity by accelerating the G1‐S phase transition, promoting cell proliferation and epithelial‐mesenchymal transition (EMT) while repressing apoptosis in CRC cells. Glycogen synthase kinase‐3β (GSK‐3β) was a direct target of miR‐377‐3p, and upregulated by miR‐377‐3p. Knockdown of GSK‐3β partly rescued miR‐377‐3p‐mediated malignancy characteristics. Most importantly, we showed that miR‐377‐3p promoted carcinogenesis by activating NF‐κB pathway. Taken together, our results first reported that miR‐377‐3p functions as an oncogene and promotes carcinogenesis via upregulating GSK‐3β expression and activating NF‐κB pathway in hCRC cells.
Retracted: Interleukin‐6 promotes the migration and cellular senescence and inhibits apoptosis of human intrahepatic biliary epithelial cells
Authors: Li Ran , Dong Juan , Bu Xiu‐Qin , Huang Yong , Yang Jing‐Yu , Dong Xuan , Liu Jie
Published: August 2017

Biliary epithelial cells (BEC) are closely related to some immune regulatory bile duct diseases. However, the complexity and polymorphism of the morphology and function of bile duct cells have hindered further investigation. Therefore, the aim of this study is to investigate how interleukin‐6 (IL‐6) affects the migration, cellular senescence, and apoptosis of human intrahepatic biliary epithelial cells (HIBECs). The HIBECs were stimulated by different concentrations of IL‐6 (0, 5, 10, 15, and 20 ng/mL, respectively). Transwell assay was performed in order to measure the migration abilities, positive β‐Galactosidase staining for the cellular senescence of HIBECs, MTT assay for changes of proliferation after IL‐6 treatment and flow cytometry for cell cycle and apoptosis. The reverse transcription quantitative polymerase chain reaction (RT‐qPCR) and Western blotting were conducted in order to detect the mRNA and protein expressions of epithelial‐mesenchymal transition (EMT) markers in HIBECs. In comparison to the 0 ng/mL group, in the 5, 10, 15, and 20 ng/mL groups, a significant increase in the number of migratory HIBECs, proliferation, along with mRNA and protein expressions of EMT markers was observed. While the mRNA and protein expressions of epithelial markers, the number of β‐galactosidase positive staining cells, as well as apoptosis rate of HIBECs dramatic decreased. Further, the aforementioned changes were significantly more evident in the 15 and 20 ng/mL groups in comparison to the 5 and 10 ng/mL groups. IL‐6 may stimulate EMT, enhance the migration and proliferation, and inhibit apoptosis of HIBECs, thus delaying cellular senescence.
Ouabain attenuates the oxidative stress induced by lipopolysaccharides in the cerebellum of rats
Authors: Garcia Israel José Pereira , Kinoshita Paula Fernanda , de Oliveira Braga Italo , Parreira Gabriela Machado , Mignaco Julio Alberto , Scavone Cristoforo , Barbosa Leandro Augusto , de Lima Santos Hérica
Published: August 2017

Our study aimed to analyze the effect of ouabain administration on lipopolysaccharide (LPS)‐induced changes in oxidative parameters, membrane lipid composition, and the activities of some important enzymes of the nervous system. The content of phospholipids, cholesterol, and gangliosides were analyzed in Wistar rats after intraperitoneal injection of ouabain (1.8 μg/kg), LPS (200 μg/kg), or saline. Oxidative parameters were also evaluated, including the activities of superoxide dismutase, catalase and glutathione peroxidase, the levels of glutathione and lipid peroxidation, as well as Na,K‐ATPase activity and the level of glutamate transporter EAAT4. Administration of LPS resulted in increased oxidative stress, as evidenced by an increase in lipid peroxidation levels, glutathione peroxidase activity, decreased catalase activity and reduced glutathione levels. All changes recorded were attenuated by pretreatment with ouabain. Administration of ouabain plus LPS enhanced the total ganglioside content and EAAT4 levels, but failed to alter the Na,K‐ATPase activity. Our data suggest a neuroprotective effect of ouabain against LPS‐induced oxidative stress by promoting membrane lipid remodeling and increasing the expression of glutamate transporter EAAT4. Our results emphasize that the observed oxidative stress is not correlated with Na,K‐ATPase, but with a possible ouabain‐mediated effect on cellular signaling. The relevance of our results extends beyond LPS‐induced changes in oxidative parameters, as nanomolar doses of ouabain might prove useful in neurodegenerative models. Further study of other cardenolides and related molecules, as well as the development of new molecules derived from ouabain, could also prove useful in the fight against the oxidative and/or general cell stress triggered by neuronal pathologies.
A TP73‐AS1/miR‐200a/ZEB1 regulating loop promotes breast cancer cell invasion and migration
Authors: Zou Qiongyan , Zhou Enxiang , Xu Feng , Zhang Danhua , Yi Wenjun , Yao Jia
Published: August 2017

Breast cancer (BC) is one of the leading causes of cancer deaths worldwide and the most common cancer among women. In our previous study, we revealed that lncRNA TP73‐AS1 promotes breast cancer cell proliferation through directly binding to miR‐200a. Herein, we evaluated the effect of TP73‐AS1 in breast cancer cell invasion and migration, and further demonstrated the direct binding between TP73‐AS1 and miR‐200a, between miR‐200a and 3′UTR of ZEB1, an essential metastasis‐related transcription factor. TP73‐AS1 promoted ZEB1 expression via competing with ZEB1 3′UTR for miR‐200a binding. Moreover, ZEB1 could bind to the promoter region of TP73‐AS1 to activate its expression. TP73‐AS1 and ZEB1 expression was up‐regulated, whereas miR‐200a expression was down‐regulated in breast cancer tissues. Taken together, we demonstrated a TP73‐AS1/miR‐200a/ZEB1 regulating loop in breast cancer cells, which promote cancer cell invasion and migration through regulating E‐cadherin and Twist expression. Suppressing TP73‐AS1 expression to rescue miR‐200a expression, thus to inhibit ZEB1 and Twist expression and up‐regulate E‐cadherin might improve breast cancer cell invasion and migration.
FGFR2 regulation by picrasidine Q inhibits the cell growth and induces apoptosis in esophageal squamous cell carcinoma
Authors: Shi Yuanyuan , Liu Xuejiao , Fredimoses Mangaladoss , Song Mengqiu , Chen Hanyong , Liu Kangdong , Lee Mee‐Hyun , Dong Zigang
Published: August 2017

Fibroblast growth factor receptor (FGFR) 2 and its downstream signaling cascades, PI3 K/AKT/mTOR is playing an important role in cell survival and proliferations. In this study, we firstly found that picrasidine Q (PQ), an alkaloid component extracted from Angelica keiskei species, has the capacity of anti‐cell transformation and anti‐cancer. After ligand shape similarity approach of PQ, we found that PQ targeted FGFR 2 and verified by FGFR2 kinase assay as well as computational docking model. FGFR2 highly expressed in esophageal cancer tissues and PQ inhibited fibroblast growth factor (FGF)‐induced cell transformation. Furthermore, PQ inhibited cell proliferation and induced cell cycle arrest and apoptosis in KYSE30, KYSE410, and KYSE450 esophageal squamous cell carcinoma (ESCC) cells. It was confirmed by detecting of biological markers such as cyclinD1, cyclinD3 and cyclinB1 for cell cycle or cleaved caspase‐7, caspase‐3, and PARP for apoptosis. PQ targeting of FGFR2 kinase activities suppressed downstream target proteins including phosphorylation of AKT and mTOR but not MEK/ERK signaling pathways. Taken together, our results are the first to identify that PQ might be a chemopreventive and chemotherapeutic agent by direct targeting FGFR2 and inhibiting cell proliferation of ESCC cells.
Oroxylin A prevents angiogenesis of LSECs in liver fibrosis via inhibition of YAP/HIF‐1α signaling
Authors: Zhang Chenxi , Bian Mianli , Chen Xingran , Jin Huanhuan , Zhao Shifeng , Yang Xiang , Shao Jiangjuan , Chen Anping , Guo Qinglong , Zhang Feng , Zheng Shizhong
Published: August 2017

Angiogenesis of liver sinusoidal endothelial cells (LSECs) accompanies with hypoxia in liver fibrosis and they are of mutual promotion, which has raised wide concern. Here we established murine model of liver fibrosis and found that oroxylin A (40 mg/kg) could ameliorate angiogenesis in liver fibrosis may related to hypoxia inducible factor 1α (HIF‐1α). The underlying mechanism was further investigated by isolating and culturing murine primary LSECs. Hypoxia induced vascular endothelial growth factor A (VEGF‐A), angiopoietin 2 (Ang‐2), and platelet endothelial cell adhesion molecule‐1 (PECAM‐1/CD31) elevated in LSECs were reduced by oroxylin A or acriflavine (ACF, an HIF‐1α inhibitor), indicating HIF‐1α involved the angiogenesis of LSECs. Additionally, interference with Yes‐associated protein (YAP) significant downregulated the protein expression of HIF‐1α and VEGF‐A, while YAP plasmid exhibited an opposite effect. We next found that oroxylin A inhibited hypoxia‐induced nuclear translocation of YAP, which may influence the accumulation of HIF‐1α and subsequently decrease transcription of downstream target gene including VEGF‐A and Ang‐2, thereby exerting an anti‐angiogenic activity.
Effect of solvation on the ionization of guanine nucleotide: A hybrid QM/EFP study
Authors: Chakraborty Rahul , Bose Samik , Ghosh Debashree
Published: August 2017

Ionization of nucleobases is affected by their biological environment, which includes both the effect of adjacent nucleotides as well as the presence of water around it. Guanine and its nucleotide have the lowest ionization potentials among the various DNA bases. Therefore, the threshold of ionization is dependent on that of guanine and its characterization is crucial to the prediction of interaction of light with DNA. We investigate the effect of solvation on the vertical ionization energies (VIEs) of guanine and its nucleotide. In this work, we have used hybrid quantum mechanics/molecular mechanics (QM/MM) approach with effective fragment potential as the MM method of choice and equation‐of‐motion coupled‐cluster for ionization potential with singles and doubles (EOM‐IP‐CCSD) as the QM method. The performance of the hybrid scheme with respect to the full QM method shows an accuracy of
0.02–0.04 eV. The lowest few ionizations of the nucleotide are found to be from different parts of the moiety, that is, the nucleic acid base, phosphate, or sugar, and these ionization energies are very closely spaced giving rise to a very complicated spectrum. Furthermore, microsolvation has large effects on these ionizations and can lead to red or blue shift depending on the position of the water molecule. Even a single water molecule can change the order of ionized states in the nucleotide. The VIEs of the bulk solvated chromophores are predicted and compared to existing experimental spectra. The predominant role of polarization in the solvatochromic shift is noticed. © 2017 Wiley Periodicals, Inc.
Two faces of triel bonds in boron trihalide complexes
Authors: Grabowski Sławomir J.
Published: August 2017

The N⋅⋅⋅B triel bonds in complexes of boron trihalides, BX3(X = F, Cl, Br, and I), with species acting as Lewis bases through the nitrogen center, NH3, N2, and HCN, are analyzed theoretically (MP2/aug‐cc‐pVTZ calculations). It is confirmed that stronger Lewis acid properties of the boron center are observed for the BCl3moiety than for the BF3one in complexes with the strong Lewis base (NH3); while the opposite order is observed for complexes with the weak Lewis base (N2). The BX3NCH complexes (for X = Cl, Br, and I) are characterized by two tautomeric forms and by two corresponding N⋅⋅⋅B distances, the shorter one possesses characteristics of the covalent bond. In a case of the BF3NCH complex one energetic minimum is observed.Ab initiocalculations are supported by an analysis of molecular electrostatic potentials (EPs) and electron density distributions. The quantum theory of ‘atoms in molecules’ and the decomposition of the energy of interaction are applied. The aforementioned acidity orders as well as the existence of two tautomers for some of complexes result partly from the electrostatic interactions' balance; the EP distribution is different for the BF3species than for the other BX3species where X = Cl, Br, and I. © 2017 Wiley Periodicals, Inc.
Synthesis, DFT Study, and Antitumor Activity of Some New Heterocyclic Compounds Incorporating Isoxazole Moiety
Authors: Hamama Wafaa S. , Ibrahim Mona E. , Zoorob Hanafi H.
Published: August 2017

Thiazolidin‐4‐one derivative 3 was synthesized by the transformation of chloroacetamide derivative 2 with NH4SCN.The condensation of 3 with p‐anisaldehyde afforded the corresponding arylidene derivative 4. Also, the alkylation of chloroacetamide derivative 2 with different heterocyclic compounds was investigated. Annulation of 5‐amino‐3‐methylisoxazole (1) with α‐halocarbonyl compounds 12 and 14 furnished pyrrolo[3,2‐d]isoxazole and isoxazolo[5,4‐b]azepin‐6‐one derivatives 13 and 15, respectively, while reaction of 1 with 1‐chloro‐4‐(chloromethyl)benzene gave the monoalkylated product 17. The newly synthesized compounds were screened for their antitumor activity, and the geometry optimizations are in a good agreement with the experimentally observed data.
Effect of Modafinil on Cognitive Function in Intensive Care Unit Patients: A Retrospective Cohort Study
Authors: Mo Yoonsun , Thomas Michael C. , Miano Todd A. , Stemp Leo I. , Bonacum Julia T. , Hutchins Kathleen , Karras George E.
Published: August 2017

Modafinil therapy, a nonamphetamine cognition‐enhancing agent, holds the potential to improve recovery from cognitive impairment after intensive care unit (ICU) admission. To date, however, there is a paucity of data on modafinil use in the ICU setting. The purpose of this study was to explore the role of modafinil for improvement in cognition in ICU patients. This retrospective cohort study evaluated a total of 60 ICU patients with any ventilatory support who started on modafinil during their ICU stay from January 1, 2010, to March 19, 2016. The requirements of opioids and sedatives, as well as the lowest and average scores of the Glasgow Coma Scale (GCS) and Riker Sedation‐Agitation Scale (SAS), were recorded during 48 hours before and after the start of modafinil therapy in 6‐hour periods. The average daily modafinil dose of 170 mg was given for a median duration of 9 days. Modafinil administration was associated with a small, nonsignificant increase in GCS by 0.34 points after controlling for age, baseline severity of illness, and changes in sedation and analgesia over time (95%CI, −0.34 to 0.73 points; P = .0743). No major modafinil‐associated adverse effects were observed. Modafinil administration did not significantly improve cognitive function in ICU patients within 48 hours of initiation. However, because of lack of robust evidence, the impact of modafinil on overall patient outcomes in the ICU remains unclear and needs further investigation.
An Efficient New Route for the Synthesis of Some 3‐Hterocyclylquinolinones via Novel 3‐(1,2‐Dihydro‐4‐hydroxy‐1‐methyl‐2‐oxoquinolin‐3‐yl)‐3‐oxopropanal and Their Antioxidant Screening
Authors: Hassan Mohamed M. , Hassanin Hany M.
Published: August 2017

3‐(4‐hydroxy‐1‐methylquinoline‐3‐yl)‐3‐oxoproponal (5) was synthesized from 3‐[(E)‐3‐(dimethylamino)‐2‐propenoyl]‐4‐hydroxy‐1‐methyl‐2(1H)‐quinolinone (3) and was utilized as a starting precursor material. A convenient new route to functionalized 3‐heterocyclyl 4‐hydroxy‐2(1H)‐quinolinones such as pyrazolyl, isoxazolyl, pyrimidinyl, azepineyl, pyridonyl, and pyranyl heterocycles was described via cyclization of compound 5 with some N and C‐nucleophiles. The newly synthesized aldehyde 5 showed only one ring closure possibility with maximum yield instead of using compound 3 that exhibited different regioselective ring closure routes with minimum yields. All newly synthesized products were structurally elucidated on the basis of their relevant spectroscopic data and elemental microanalyses. The antioxidant activity of the products was screened in a series of in vitro tests.
An Efficient One‐Pot Synthesis of New Coumarin Derivatives as Potent Anticancer Agents under Microwave Irradiation
Authors: El‐Naggar Abeer M. , Hemdan Magdy M. , Atta‐Allah Saad R.
Published: August 2017

An efficient and rapid synthesis of coumarin derivatives was accomplished via reactions of 3‐(3‐(4‐methoxyphenyl)acryloyl)‐2H‐chromen‐2‐one (3) with different carbon nucleophiles such as ethyl acetoacetate, ethyl cyanoacetate, malononitrile, and ethyl benzoylacetate via conventional heating and microwave irradiation conditions and were used as source of pyran and pyridine derivatives bearing coumarin moiety 4–11. Compound 9a was condensed with different carbon electrophiles triethylorthoformate, phenylisothiocyanate, carbon disulfide, benzoylchloride, and acetylchloride that afforded the corresponding chromen derivatives 12–16. All the newly synthesized compounds were characterized by elemental and spectroscopic evidences. All of synthesized compounds were tested for in vitro cytotoxicity. The preliminary screening results showed that most of the compounds had moderate cytotoxic activity against HCT‐116 and MCF‐7 cell lines. Nevertheless, compound 10 exhibited potent activity against the two cell lines, which was comparable with the standard drug 5‐fluorouracil.
Activity of Zn and Mg phthalocyanines and porphyrazines in amyloid aggregation of insulin
Authors: Kovalska V. , Chernii S. , Losytskyy M. , Ostapko J. , Tretyakova I. , Gorski A. , Chernii V. , Yarmoluk S.
Published: August 2017

Formation of the deposits of protein aggregates—amyloid fibrils in an intracellular and intercellular space—is common to a large group of amyloid‐associated disorders. Among the approaches to develop of therapy of such disorders is the use of agents preventing protein fibrillization. Polyaromatic complexes—porphyrins and phthalocyanines—are known as compounds possessing anti‐fibrillogenic activity.

Here, we explore the impact of related macrocyclic complexes—phthalocyanines (Pc) and octaphenyl porphyrazines (Pz) of Mg and Zn—on aggregation of amyloidogenic protein insulin. Pz complexes are firstly reported as compounds able to affect protein fibrillization.

The effect of Pc and Pz complexes on the kinetics and intensity of insulin aggregation was studied by the fluorescent assay using amyloid sensitive cyanine dye. This has shown the impact of metal ion on the anti‐fibrillogenic properties of macrocyclic complexes—the effect on the fibrillization kinetics of Mg‐containing compounds is much more pronounced comparing to that of Zn analogues.

Scanning electron microscopy experiments have demonstrated that filamentous fibrils are the main product of aggregation both for free insulin and in the presence of macrocyclic complexes. However, those fibrils are distinct by their length and proneness to lateral aggregation. The Pc complexes cause the increase in variation of fibrils length 0.9 to 2.7 nm in opposite to 1.4 to 2.0 nm for free insulin, whereas Pz complexes cause certain shortening of the fibrils to 0.8 to 1.6 nm.

The averaged size of the fibrils population was estimated by dynamic light scattering; it correlates with the size of single fibrils detected by scanning electron microscopy.
Identifying the stacking order of multilayer graphene grown by chemical vapor deposition via Raman spectroscopy
Authors: Lin Miao‐Ling , Chen Tao , Lu Wei , Tan Qing‐Hai , Zhao Pei , Wang Hong‐Tao , Xu Yang , Tan Ping‐Heng
Published: August 2017

Large‐area monolayer (1LG) and multilayer graphene (MLG) grown by chemical vapor deposition (CVD) have been of great technological importance for the graphene electronics and photonics. Such CVD‐grown MLG (CVD‐MLG) flakes consist of multiple single crystal domains, whose stacking orders can be diverse due to the various choices of layer number, stacking sequence, and twist angle. Here, we demonstrated a way to identify the stacking order of CVD‐MLG via Raman spectroscopy. The CVD‐grown 1LG can be identified by comparing its optical contrast or G mode intensity with those of the corresponding mechanically exfoliated 1LG on the same substrate. Once the CVD‐grown 1LG is distinguished, all the layer numbers of CVD‐MLG flakes can be ascertained by the peak positions of their layer‐breathing modes. The stacking sequence of a CVD‐MLG flake can be determined by the shear modes, and the twist angles of twisted interfaces in the CVD‐MLG flake are accessible by the so‐called R modes. In this way, one can determine whether an MLG sample exhibit a fully nonstacked arrangement or if 2 or 3 of these layers are stacked in the AB stacking, including the order where the stacked layers would appear with respect to the nonstacked layers. This reliable way to identify the stacking orders advances an important step for the characterization of CVD‐MLGs, shedding light on tailoring the properties of CVD‐MLGs with specific stacking order on demand. Copyright © 2017 John Wiley & Sons, Ltd.
Quantitative surface‐enhanced resonance Raman scattering analysis of methylene blue using silver colloid
Authors: Anastasopoulos J.A. , Soto Beobide A. , Manikas A.C. , Voyiatzis G.A.
Published: August 2017

Quantitative analysis of methylene blue (MB) has been performed with Surface Enhanced Raman Scattering, SERS, using citrate reduced silver colloid activated with NaCl. In this study, the combination of SERS occurring at the proximity of the plasmon surface and of resonance Raman with excitation wavelength matched to the maximum absorbance of the molecule being analyzed, was successfully applied to maximize the Raman scattering intensity. The surface‐enhanced resonance Raman scattering (SERRS) spectra of aqueous solutions of the dye at various concentrations were collected in right‐angle scattering geometry configuration which results favorable when nanocolloidal dispersions are used. The MB concentration was correlated with the intensity of the peak centered at 1,625 cm−1 in the SERRS spectrum and this correlation resulted in an extremely sensitive quantitative investigation of the MB with limit of detection in pM level. Among others, this method can be easily applied for the examination of both the selectivity of waste water purification membranes for relevant small molecular weight contaminants or/and the solar photocatalytic effectiveness of such membranes for the degradation of pertinent pollutants by their quantitative assessment in the permeate at very low concentration range.
Raman spectroscopic determination of Sr/Ca ratios of calcite samples
Authors: Shibano Yusuke , Takahata Kohei , Kawano Jun , Watanabe Tsuyoshi , Enomoto Daisuke , Kagi Hiroyuki , Kamiya Natsumi , Yamamoto Junji
Published: August 2017

We investigated the relation between Sr# [= 100 Sr/(Sr + Ca) in mol] of calcites and their Raman spectra for Sr‐doped calcite samples with Sr# of 0–13.2. We selected 3 major Raman peaks observed at 150–155 cm−1 (peak A), 274–282 cm−1 (peak B), and 710–712.5 cm−1 (peak C). With increasing Sr#, the peaks shifted monotonously to lower wavenumbers. We obtained a linear expression for peak B as Sr# = −1.734 ΔνB + 76.93, where ΔνB is a separation between peak B and a neon emission line of 237.07 cm−1 in Raman shift. The present spectroscopic analysis can ascertain Sr# of calcite with precision of ±1.26 in the range of Sr# of 0–13.2.
Effects of gamma‐irradiation on cotyledon cell separation and pectin solubilisation in hard‐to‐cook cowpeas
Authors: Jombo Talknice Z , Minnaar Amanda , Taylor John RN
Published: August 2017

BACKGROUND

Cowpeas stored under high temperature and humidity develop the hard‐to‐cook defect (HTC). This defect greatly increases cooking times and energy costs. To better understand the mechanisms involved in the HTC defect development, the effects of gamma‐irradiation on cotyledon cellular structure and pectin solubility in two cowpea cultivars with different susceptibility to HTC defect were investigated.

RESULTS

Gamma‐irradiation decreased cotyledon cell wall thickness, increased cell size, and intercellular spaces in both cowpea cultivars and reduced cooking time of the less HTC susceptible cultivar. However, it did not reverse the HTC defect in the susceptible cultivar. Gamma‐irradiation also increased the levels of cold water‐ and hot water‐soluble pectin. The irradiation effects were thus mainly due to hydrolysis of pectin fractions in the cell walls. However, chelator‐soluble pectin (CSP) solubility was not affected.

CONCLUSION

As the cell wall changes brought about by gamma‐irradiation were associated with pectin solubilisation, this supports the phytate–phytase–pectin theory as a major cause of the HTC defect. However, the non‐reversal of the defect in HTC susceptible cowpeas and the absence of an effect on CSP indicate that other mechanisms are involved in HTC defect development in cowpeas, possibly the formation of alkali‐soluble, ester bonded pectins. © 2017 Society of Chemical Industry
Effects of dietary coated cysteamine hydrochloride on pork color in finishing pigs
Authors: Bai Miaomiao , Liu Hongnan , Xu Kang , Zou Bingjie , Yu Rong , Liu Yanhong , Xing Weigang , Du Haitao , Li Yong , Yin Yulong
Published: August 2017

BACKGROUND

Coated cysteamine hydrochloride (CC) was applied as a feed additive in animal production. The influence and the mechanisms of CC used as a feed additive in promoting meat quality in finishing pigs were investigated.

RESULTS

Dietary CC supplementation increased (P < 0.05) the a* and H* values and reduced (P < 0.05) the L* value in the longissimus dorsi muscles at 48 h postmortem (P < 0.05). The deoxymyoglobin content was enhanced (P < 0.05) and the metmyoglobin and malondialdehyde contents were reduced (P < 0.05) in pigs fed the dietary CC. Pigs fed a dietary CC of 0.035 g kg−1 had a lower cooking loss (P < 0.05) and a higher a* (24 h) value in the longissimus dorsi muscles than pigs on control treatment. The messenger RNA expression of superoxide dismutase 1 was upregulated (P < 0.05) in the longissimus dorsi.

CONCLUSION

Dietary supplementation with CC could improve antioxidant status and delay meat discoloration by improving glutathione levels and antioxidase activity after longer chill storage (for 48 h after slaughter). Dietary supplementation with CC at 0.035 g kg−1 may promote the stability of pork color by reducing oxidation. © 2017 Society of Chemical Industry
Fingerprint profiles of flavonoid compounds from different Psidium guajava leaves and their antioxidant activities
Authors: Wang Lu , Wu Yanan , Bei Qi , Shi Kan , Wu Zhenqiang
Published: August 2017

Flavonoids are the main active components in Psidium guajava leaves and have many multi‐physiological functions. In this study, the flavonoid compositions were identified in the Psidium guajava leaves samples using a high‐performance liquid chromatography with time‐of‐flight electrospray ionization mass spectrometry method. A high‐performance liquid chromatography fingerprint method, combined with chemometrics, was used to perform a quality assessment of the Psidium guajava leaves samples. The eight identified flavonoid compounds including rutin, isoquercitrin, quercetin‐3‐O‐β‐d‐xylopyranoside, quercetin‐3‐O‐α‐l‐arabinopyranoside, avicularin, quercitrin, quercetin, and kaempferol were used as the chemical markers. The antioxidant activity of 15 batches of samples was examined using three different methods, and the results revealed the Psidium guajava leaves samples that had higher contents of the flavonoid compounds, glycoside and aglycone, possessed the highest antioxidant capacities. Consequently, a combination of chromatographic fingerprints and chemometric analyses was used for a quality assessment of Psidium guajava leaf tea and its derived products, which can lay the foundation for the development of plant tea resources or other herbs.
Screening, separation, and evaluation of xanthine oxidase inhibitors from Paeonia lactiflora using chromatography combined with a multi‐mode microplate reader
Authors: Wang Jing , Shi Dongfang , Zheng Meizhu , Ma Bing , Cui Jing , Liu Chunming , Liu Chengyu
Published: August 2017

Natural products have become one of the most important resources for discovering novel xanthine oxidase inhibitors, which are commonly employed in the treatment of hyperuricemia and gout. However, to date, few reports exist regarding the use of monoterpene glycosides as xanthine oxidase inhibitors. Thus, we herein report the use of ultrafiltration coupled with liquid chromatography in the screening of monoterpene glycoside xanthine oxidase inhibitors from the extract of Paeonia lactiflora (P. lactiflora), and both high‐performance counter‐current chromatography and medium‐pressure liquid chromatography were employed to separate the main constituents. Furthermore, the xanthine oxidase inhibitory activities and the mechanisms of inhibition of the isolated compounds were evaluated using a multi‐mode microplate reader by Molecular Devices. As a result, three monoterpene glycosides were separated by combined high‐performance counter‐current chromatography and medium‐pressure liquid chromatography in purities of 90.4, 98.0, and 86.3%, as determined by liquid chromatography. These three compounds were identified as albiflorin, paeoniflorin, and 1‐O‐β‐ᴅ‐glucopyranosyl‐8‐O‐benzoylpaeonisuffrone by electrospray ionization tandem mass spectrometry, and albiflorin and paeoniflorin were screened as potential xanthine oxidase inhibitors by ultrafiltration with liquid chromatography. The evaluation results of xanthine oxidase inhibitory activity corresponded with the screening results, as only albiflorin and paeoniflorin exhibited xanthine oxidase inhibitory activity.
Chinese outbound travel: Understanding the socioeconomic drivers
Authors: Huang Songshan (Sam) , Wei Xiang
Published: August 2017

This study used a national sample (N = 36,490) of Chinese urban residents to examine the relationship between outbound travel intention and some key demographic, economic, and geographic variables. Findings indicate that education, income, and paid vacation days significantly predicted outbound travel intention. Compared to residents in Tier‐4 cities in China, those in Tier‐1, ‐2, and ‐3 cities had higher probability of choosing outbound travel by 13.1%, 30.9%, and 15.3%, respectively. This study draws meaningful connections between Chinese outbound tourism and the social and economic realities in China and offers an alternative approach to understanding Chinese outbound tourism.
Sonographic Overview of Usual and Unusual Disorders of the Rectus Femoris Tendon Origins
Authors: Moraux Antoine , Balbi Vincent , Cockenpot Eric , Vandenbussche Laurent , Miletic Bruno , Letartre Romain , Khalil Chadi
Published: August 2017

Rectus femoris muscle proximal injuries are not rare conditions. The proximal rectus femoris tendinous anatomy is complex and may be affected by traumatic, microtraumatic, or nontraumatic disorders. A good knowledge of the proximal rectus femoris anatomy allows a better understanding of injury and disorder patterns. A new sonographic lateral approach was recently described to assess the indirect head of the proximal rectus femoris, hence allowing for a complete sonographic assessment of the proximal rectus femoris tendons. This article will review sonographic features of direct, indirect, and conjoined rectus femoris tendon disorders.
Impact of Agropastoral Management on Wind Erosion in Sahelian Croplands
Authors: Pierre Caroline , Kergoat Laurent , Hiernaux Pierre , Baron Christian , Bergametti Gilles , Rajot Jean‐Louis , Abdourhamane Toure Amadou , Okin Gregory S. , Marticorena Beatrice
Published: August 2017

In the Sahel, climate change and demographic growth are raising major concerns about the ability of crop yields to support the local population. Agropastoral management affects wind erosion (e.g., through crop residue management and tillage practices, which modify surface characteristics), which itself substantially affects soil fertility and thus crop yields. There is therefore a need to assess the potential impact of the main Sahelian cropping practices – like sowing, manuring, and crop residue management – on wind erosion. Using a modeling approach adapted to an experimental site located in southwestern Niger over the period 2006–2012, and scenarios that describe a set of agropastoral practices, the impacts of these practices on wind erosion are simulated and compared. The results indicate that horizontal fluxes differ by a factor of 10 among scenarios, with annual horizontal fluxes ranging from 121 to 1,317 kg m−1. Modeled wind erosion is most sensitive to the mass of crop residues in the late dry season, but different practices dealing with crop growth or with crop residue management may result in fluxes of the similar magnitude. The collection of the crop residues after grain harvest increases wind erosion, whereas grazing might have mixed effects, probably further mediated by the mobility of livestock as a response to forage availability. The seasonal dynamics of the monthly cumulated horizontal fluxes vary depending on practice; however, the annual cumulated horizontal fluxes are closely correlated with meteorological conditions such as wind speed and rainfall in the previous year. Copyright © 2017 John Wiley & Sons, Ltd.
Environmental vibrios represent a source of antagonistic compounds that inhibit pathogenic Vibrio cholerae and Vibrio parahaemolyticus strains
Authors: Burks David J. , Norris Stephen , Kauffman Kathryn M. , Joy Abigail , Arevalo Philip , Azad Rajeev K. , Wildschutte Hans
Published: August 2017

With the overuse of antibiotics, many pathogens including Vibrio cholerae and Vibrio parahaemolyticus have evolved multidrug resistance making treatment more difficult. While understanding the mechanisms that underlie pathogenesis is crucial, knowledge of bacterial interactions of V. cholerae and V. parahaemolyticus could provide insight to their susceptibility outside of the human host. Based on previous work showing competition among environmental strains, we predict that marine‐derived bacteria should inhibit Vibrio pathogens and may be a source of unique antibiotic compounds. We tested a collection of 3,456 environmental Vibrio isolates from diverse habitats against a panel of V. cholerae and V. parahaemolyticus, and identified 102 strains that inhibited the growth of these pathogens. Phylogenetic analysis revealed that 40 pathogen‐inhibiting strains were unique at the hsp60 gene sequence while 62 of the isolates were identical suggesting clonal groups. Genomic comparisons of ten strains revealed diversity even between clonal isolates and were identified as being closely related to known Vibrio crassostreae, Vibrio splendidus, and Vibrio tasmaniensis strains. Further analysis revealed multiple biosynthetic gene clusters within all sequenced genomes that encoded secondary metabolites with potential antagonistic activity. Thus, environmental vibrios represent a source of compounds that inhibit Vibrio pathogens.
The protein restriction mimetic Resveratrol is an autophagy inducer stronger than amino acid starvation in ovarian cancer cells
Authors: Ferraresi Alessandra , Titone Rossella , Follo Carlo , Castiglioni Andrea , Chiorino Giovanna , Dhanasekaran Danny N. , Isidoro Ciro
Published: August 2017

The potential benefit of nutrient starvation in the prevention and treatment of cancer is presently under consideration. Resveratrol (RV), a dietary polyphenol acting as a protein (caloric) restriction mimetic, could substitute for amino acid starvation. The effects of starvation and of caloric restriction are mediated, among others, by autophagy, a process that contributes to cell homeostasis by promoting the lysosomal degradation of damaged and redundant self‐constituents. Up‐regulation of autophagy favors cell survival under nutrient shortage situation, and may drive cancer cells into a non‐replicative, dormant state. Both RV and amino acid starvation effectively induced the aminoacid response and autophagy. These processes were associated with inhibition of the mTOR pathway and disruption of the BECLIN1‐BCL‐2 complex. The number of transcripts positively impinging on the autophagy pathway was higher in RV‐treated than in starved cancer cells. Consistent with our data, it appears that RV treatment is more effective than and can substitute for starvation for inducing autophagy in cancer cells. The present findings are clinically relevant because of the potential therapeutic implications.