bluuebunny/crossref_metadata_2025 huggingface dataset:
Self‐assembled biogenic melanin modulated surface chemistry of biopolymers‐colloidal silica composite porous matrix for the recovery of uranium
Authors: Tripathi A. , Melo J. S.
Published: August 2018

A new composite porous matrix surface modulated by self‐assembled melanin was developed and investigated for its affinity to bind uranium from an aqueous medium. The composite matrix was synthesized using biopolymers (i.e., agarose and alginate) and inorganic colloidal silica nanoparticles (AACS) by the process of cryotropic‐gelation at subzero‐temperature. Post‐synthesis surface modification of AACS matrix with melanin (MAACS) was performed by green chemistry. The in situ sequestrial conversion of l‐Dopa by the biocatalytic activity of tyrosinase enzyme allows the formation of melanin on the surface of AACS matrix. The functional moieties on the matrix display fast kinetics and high binding capacity with respect to uranium. MAACS matrix showed high porosity (~90%) with interconnected pores, high swelling kinetics and permeability. Other physicochemical properties of the matrix, such as thermal stability, storage modulus, and surface charge potential were found to be increased, while percent degradation decreased, which demonstrate improved properties of the matrix after impregnation of silica nanoparticles and surface functionalization with melanin. Thermodynamic parameters suggest that the binding of uranyl ions is passive and spontaneous. The concentrated recovery of uranium was achieved with reusability potential of adsorbent. These results suggest an environment friendly and safer method for the recovery of uranium. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 46937.
Imine‐N‐Heterocyclic Carbenes as Versatile Ligands in Ruthenium(II) p‐Cymene Anticancer Complexes: A Structure–Activity Relationship Study
Authors: Yang Yuliang , Guo Lihua , Tian Zhenzhen , Liu Xicheng , Gong Yuteng , Zheng Hongmei , Ge Xingxing , Liu Zhe
Published: August 2018

A family of novel imine‐N‐heterocyclic carbene ruthenium(II) complexes of the general formula [(η6‐p‐cymene)Ru(C^N)Cl]PF6− (where C^N is an imine‐N‐heterocyclic carbene chelating ligand with varying substituents) have been prepared and characterized. In this imine‐N‐heterocyclic carbene chelating ligand framework, there are three potential sites that can be modified, which distinguishes this class of ligand and provides a body of flexibilities and opportunities to tune the cytotoxicity of these ruthenium(II) complexes. The influence of substituent effects of three tunable domains on the anticancer activity and catalytic ability in converting coenzyme NADH to NAD+ is investigated. This family of complexes displays an exceedingly distinct anticancer activity against A549 cancer cells, despite their close structural similarity. Complex 9 shows the highest anticancer activity in this series against A549 cancer cells (IC50=14.36 μm), with an approximately 1.5‐fold better activity than the clinical platinum drug cisplatin (IC50=21.30 μm) in A549 cancer cells. Mechanistic studies reveal that complex 9 mediates cell death mainly through cell stress, including cell cycle arrest, inducing apoptosis, increasing intracellular reactive oxygen species (ROS) levels, and depolarization of the mitochondrial membrane potential (MMP). Furthermore, lysosomal damage is also detected by confocal microscopy.
Analysis and control of spatial limit sets and spatial chaos appearance in mimo cascade connected nonlinear systems
Authors: Zlatkovic Bojana M. , Samardzic Biljana
Published: August 2018

The oscillatory and chaotic dynamics of MIMO cascade connected nonlinear systems are analyzed in this paper. For that purpose the known theorems of limit sets existence in appropriate nonlinear discrete systems are used. Control of spatial limit sets and spatial chaos appearance in MIMO cascade connected nonlinear systems using modified Pyragas method is also analyzed. The results are illustrated by examples and confirmed with simulations.
Drinking water disinfection byproducts and risk of orofacial clefts in the National Birth Defects Prevention Study
Authors: Weyer Peter , Rhoads Anthony , Suhl Jonathan , Luben Thomas J. , Conway Kristin M. , Langlois Peter H. , Shen Dereck , Liang Dong , Puzhankara Soman , Anderka Marlene , Bell Erin , Feldkamp Marcia L. , Hoyt Adrienne T. , Mosley Bridget , Reefhuis Jennita , Romitti Paul A. ,   The National Birth Defects Prevention Study
Published: August 2018

Background

Maternal exposure to drinking water disinfection byproducts (DBP)s may contribute to orofacial cleft (OFC) development, but studies are sparse and beset with limitations.

Methods

Population‐based, maternal interview reports of drinking water filtration and consumption for 680 OFC cases (535 isolated) and 1826 controls were linked with DBP concentration data using maternal residential addresses and public water system monitoring data. Maternal individual‐level exposures to trihalomethanes (THM)s and haloacetic acids (HAA)s (µg/L of water consumed) were estimated from reported consumption at home, work, and school. Compared to no exposure, associations with multisource maternal exposure <1/2 or ≥1/2 the Maximum Contaminant Levels (MCL)s for total THMs (TTHM)s and HAAs (HAA5) or Maximum Contaminant Level Goals (MCLG)s for individual THMs and HAAs (if non‐zero) were estimated for all OFCs and isolated OFCs, cleft palate (CP), and cleft lip ± cleft palate (CL/P) using logistic regression analyses.

Results

Compared to controls, associations were near or below unity for maternal TTHM, HAA5, and individual THM exposures with all OFCs and isolated OFCs, CP, and CL/P. Associations also were near or below unity for individual HAAs with statistically significant, inverse associations observed with each OFC outcome group except CL/P.

Conclusions

This study examined associations for maternal reports of drinking water filtration and consumption and maternal DBP exposure from drinking water with OFCs in offspring. Associations observed were near or below unity and mostly nonsignificant. Continued, improved research using maternal individual‐level exposure data will be useful in better characterizing these associations.
Bioinspired Load‐Bearing Hydrogel Based on Engineered Sea Anemone Skin‐Derived Collagen‐Like Protein
Authors: Yang Yun Jung , Choi Yoo Seong , Cha Hyung Joon
Published: August 2018

With the help of recombinant DNA technology, many protein candidates have been investigated and engineered for biomaterial applications. Particularly, several repeat sequences with unique secondary structures have been selected as minimal building blocks for biosynthesis to improve the mechanical properties of biomaterials. However, most of these structural proteins have been limited to silk, elastin, collagen, and resilin for decades. In the present work, new repeat sequence found in sea anemone are characterized and biosynthesized into a recombinant protein (named anegen) for potential use as a load‐bearing biomaterial. Because its repeat sequence unit has a unique polyproline II structure, which is prevalently found in the triple‐helix of collagen, it is assumed to be a promising structural protein candidate that can provide conformational flexibility and elasticity. Because anegen has ≈10% tyrosine residues, inspiration is taken from di‐tyrosine crosslinking in the hinge structures of insects, which can be initiated by light activation. It is found that the anegen hydrogel shows higher mechanical properties than a gelatin hydrogel and endures a compression series without deformation. Moreover, the mechanical properties of the anegen hydrogel are controllable through different crosslinking conditions in a wide range of material applications. Importantly, the anegen hydrogel exhibited suitable cell retainability and cell morphology as an implantable biomaterial. Thus, based on its mechanical properties and biocompatibility, the anegen hydrogel can be used as a potential load‐bearing and cell‐loading scaffolding biomaterial in the tissue and biomedical engineering fields.
Rapid identification of antimicrometastases drugs using integrated model systems with two dimensional monolayer, three dimensional spheroids, and zebrafish xenotransplantation tumors
Authors: Fu Afu , Peh Yu Ming , Ngan Weida , Wei Na , Luo Kathy Qian
Published: August 2018

Treating systemic metastases at the micrometastatic stage is a potential strategy to inhibit cancer metastasis. This study aims to establish an apoptosis sensor‐based platform for rapid, effective, and noninvasive identification of drugs that can inhibit the proliferation of micrometastatic cancer cells. We stably transfected the plasmid DNA encoding the fluorescence resonance energy transfer‐based caspase‐3 sensor into highly metastatic melanoma B16F10 cells. The resulting B16F10‐C3 cells were applied for screening of antiproliferative and proapoptotic drugs in two‐dimensional (2D) monolayer, three‐dimensional (3D) spheroids, and zebrafish xenotransplantation tumors. All studies were conducted in 96‐well plates in a high throughput manner. Fourteen compounds including six chemotherapeutic drugs and eight kinase inhibitors were tested. Thirteen compounds failed the tests due to: Drug resistance, low efficacy, poor pharmacokinetic profile, and/or high side effects to zebrafish. The only compound that passed all tests was pan‐phosphatidylinositol 3‐kinase (PI3K) inhibitor LY294002, which inhibited the proliferation of B16F10‐C3 cells in both 2D and 3D cultures. More important, it significantly reduced the xenograft tumor size in zebrafish by decreasing the viability of metastatic cancer cells. Our study suggests that the PI3K/AKT pathway is a potential therapeutic target for the reactivation of tumor dormancy and proliferation of micrometastases. Moreover, this integrated approach is effective for rapid identification of systemic antimetastases drugs.
Reconstruction of tricarboxylic acid cycle in Corynebacterium glutamicum with a genome‐scale metabolic network model for trans‐4‐hydroxyproline production
Authors: Zhang Yu , Zhang Yun , Shang Xiuling , Wang Bo , Hu Qitiao , Liu Shuwen , Wen Tingyi
Published: August 2018

trans‐4‐Hydroxy‐
l‐proline (Hyp) is an abundant component of mammalian collagen and functions as a chiral synthon for the syntheses of anti‐inflammatory drugs in the pharmaceutical industry. Proline 4‐hydroxylase (P4H) can catalyze the conversion of
l‐proline to Hyp; however, it is still challenging for the fermentative production of Hyp from glucose using P4H due to the low yield and productivity. Here, we report the metabolic engineering of
Corynebacterium glutamicum for the fermentative production of Hyp by reconstructing tricarboxylic acid (TCA) cycle together with heterologously expressing the
p4h gene from
Dactylosporangium sp. strain RH1. In silico model‐based simulation showed that α‐ketoglutarate was redirected from the TCA cycle toward Hyp synthetic pathway driven by P4H when the carbon flux from succinyl‐CoA to succinate descended to zero. The interruption of the TCA cycle by the deletion of
sucCD‐encoding the succinyl‐CoA synthetase (SUCOAS) led to a 60% increase in Hyp production and had no obvious impact on the growth rate. Fine‐tuning of plasmid‐borne ProB* and P4H abundances led to a significant increase in the yield of Hyp on glucose. The final engineered Hyp‐7 strain produced up to 21.72 g/L Hyp with a yield of 0.27 mol/mol (Hyp/glucose) and a volumetric productivity of 0.36 g·L
−1·hr
−1 in the shake flask fermentation. To our knowledge, this is the highest yield and productivity achieved by microbial fermentation in a glucose‐minimal medium for Hyp production. This strategy provides new insights into engineering
C. glutamicum by flux coupling for the fermentative production of Hyp and related products.
Positive predictive values of fecal immunochemical tests used in the STOP CRC pragmatic trial
Authors: Nielson Carrie M. , Petrik Amanda F. , Jacob Lorie , Vollmer William M. , Keast Erin M. , Schneider Jennifer L. , Rivelli Jennifer S. , Kapka Tanya J. , Meenan Richard T. , Mummadi Rajasekhara R. , Green Beverly B. , Coronado Gloria D.
Published: August 2018

Annual fecal immunochemical testing (FIT) is cost‐effective for colorectal cancer (CRC) screening. However, FIT positivity rates and positive predictive value (PPV) can vary substantially, with false‐positive (FP) results adding to colonoscopy burden without improving cancer detection. Our objective was to describe FIT PPV and the factors associated with FP results among patients undergoing CRC screening. In an ongoing pragmatic clinical trial of mailed‐FIT outreach, clinics delivered one of three FIT brands (InSure, OC‐Micro, and Hemosure). Patients who had a positive FIT result and a follow‐up colonoscopy were included in this analysis (N = 1130). Patients’ demographic and medical histories were abstracted from electronic health records (EHR). Associations with a FP result (ie, a positive FIT result with no evidence of advanced neoplasia during follow‐up colonoscopy) were evaluated for FIT brand and patient factors using mixed‐effects multivariable logistic regression. The mean proportion of FIT‐positive results ranged from 8% in centers using the OC‐Micro test to 21% for Hemosure. PPVs for advanced neoplasia were 0.30 to 0.17, respectively (P for χ2 = 0.08). In multivariable‐adjusted models, use of Hemosure was associated with greater odds of a FP result than OC‐Micro (OR = 2.00, 95% CI: 0.47‐8.56) or InSure (OR = 1.72, 95% CI: 0.44‐6.68). However, only female sex (OR = 1.58, 95% CI: 1.19‐2.10) and history of a colorectal condition (OR = 2.17, 95% CI: 1.13‐4.15) were significantly associated with FP. In conclusion, FIT positivity varied by brand, and FP results differed by patient factors available through the EHR. These results can be used to minimize the frequency of FP results, reducing patient distress and colonoscopy burden.
Dry Reforming of Shale Gas and Carbon Dioxide with Ni‐Ce‐Al2O3 Catalyst: Syngas Production Enhanced over Ni‐CeOx Formation
Authors: Liu Yan , Wu Ye , Akhtamberdinova Zarina , Chen Xiaoping , Jiang Guodong , Liu Dong
Published: August 2018

The dry reforming of shale gas (methane and ethane with an average ratio of 4 : 1) with carbon dioxide (DRS) is considered to be a promising way to produce syngas, which widens the utilization of shale gas and mitigates carbon dioxide emission. In this paper, Ce modified Ni‐based catalysts were developed and the corresponding catalytic performances for DRS were investigated with a fixed bed reactor. Results showed that the catalyst containing 5 wt% of Ni and 5 wt% of Ce performed a best catalytic effect, including the selectivity of syngas and the carbon resistance performance, which is due to the good metal dispersion, strong interaction between Ni and Ce, and the formation of Ni‐CeOx solid solution. The electron transfer between Ni and Ce, substitution of Ni for Ce, and the sequential oxygen vacancies or defects, play significant roles in activating CH4, C2H6 and CO2. The conversion of reactant gas increased with temperature, while the selectivity of syngas is little affected with temperature. In addition, the desired catalyst containing 5 wt% of Ni and 5 wt% of Ce showed good stability in the long‐time operation, which indicates that the Ce modified Ni‐based catalyst is a promising one for the dry reforming of shale gas.
The First C−Cl Activation in Ullmann C−O Coupling by MOFs
Authors: Ramezani Leila , Yahyazadeh Asieh , Sheykhan Mehdi
Published: August 2018

It was found that introduction of only 0.03 mol % Ag(I) into the framework of Cu3(BTC)2 ⋅ xH2O in maghemite anchored CuBTC activated the inert CuBTC astonishingly to exhibit unexpected high catalytic activity for C−Cl activation in coupling of chloroarenes with phenols without the use of expensive ligands. This is the first application of mixed‐metal MOFs in the C−X activation. Putting reusability and activity together, a TON over 15000 was obtained which is the highest TON compared with all its precedents even better than the results by Pd catalysts.
Insights into Crystal Facets of Perovskite SrSnO3 as High‐Performance Photocatalysts toward Environmental Remediation
Authors: Zhang Xinhua , Hu Jindou , Cao Yali , Xie Jing , Jia Wei , Wang Shiqiang , Jia Dianzeng
Published: August 2018

To gain in‐depth insights into the relevant exposed crystal planes for the photocatalytic performance of perovskite‐structured oxides, SrSnO3 nanocrystals with different microstructures were synthesized and their photocatalytic activity for the degradation of simulated dye was investigated. The as‐obtained orthorhombic SrSnO3 nanorods with exposed {001} crystal planes showed higher photocatalytic activity for decomposing methylene blue than that of SrSnO3 nanoribbons with exposed {111} crystal planes. The surface atomic configurations revealed that the quantity of SnO2 overlayer on the {001} crystal facets is slightly greater than that on {111} crystal planes, which results in exposed {001} crystal facets of the SrSnO3 nanorods that can exhibit better activity in the photocatalytic process, due to fewer lattice defects, which act as traps for photogenerated charge carriers to decrease the recombination of photoexcited electrons and holes. This originated from narrowing of the crystal face distance and slight variation of the unit cell parameters; the crystallographic axis became shorter and the value of lattice strain became smaller. As a result, SrSnO3 nanocrystals exhibited different surface behavior under post‐treatment conditions and exhibited variation in the photocatalytic properties. The findings reported herein highlight the importance of probing the properties of surface facets in the evaluation of the photocatalytic performance of ternary metal oxides.
Synthesis of a Dimeric Base‐Stabilized Cobaltosilylene Complex for Catalytic C−H Bond Functionalization and C−C Bond Formation
Authors: Khoo Sabrina , Cao Jiajia , Yang Ming‐Chung , Shan Yu‐Liang , Su Ming‐Der , So Cheuk‐Wai
Published: August 2018

The synthesis of a dimeric base‐stabilized cobaltosilylene complex and its catalytic reactions are described. Treatment of the amidinato silicon(I) dimer [LSi:]2 (1; L=PhC(NtBu)2) with CoBr2 in toluene for 10 days afforded the dimeric amidinato cobaltosilylene [(LSi)μ‐{CoBr(LSiBr)}]2 (2), which is speculated to proceed via “LSiCoBr” and “LSiBr” intermediates in the reaction. Compound 2 is paramagnetic, with an effective magnetic moment of 2.8 μB. Its electronic structure was elucidated by single‐crystal X‐ray crystallography and DFT studies. It was capable of catalyzing C−H bond functionalization, in which a combination of 2, phosphine and MeMgI can regio‐ and stereoselectively promoted the addition of the C≡C triple bonds in alkynes to the ortho‐C−H position in arylpyridines. In addition, compound 2 catalyzed Kumada‐type coupling reactions between aryl chlorides and the Grignard reagent 2‐mesitylmagnesium bromide.
Alpha‐Synuclein Modulates the Physical Properties of DNA
Authors: Jiang Kai , Rocha Sandra , Westling Alvina , Kesarimangalam Sriram , Dorfman Kevin D. , Wittung‐Stafshede Pernilla , Westerlund Fredrik
Published: August 2018

Fundamental research on Parkinson's disease (PD) most often focuses on the ability of α‐synuclein (aS) to form oligomers and amyloids, and how such species promote brain cell death. However, there are indications that aS also plays a gene‐regulatory role in the cell nucleus. Here, the interaction between monomeric aS and DNA in vitro has been investigated with single‐molecule techniques. Using a nanofluidic channel system, it was discovered that aS binds to DNA and by studying the DNA–protein complexes at different confinements we determined that aS binding increases the persistence length of DNA from 70 to 90 nm at high coverage. By atomic force microscopy it was revealed that at low protein‐to‐DNA ratio, the aS binding occurs as small protein clusters scattered along the DNA; at high protein‐to‐DNA ratio, the DNA is fully covered by protein. As DNA‐aS interactions may play roles in PD, it is of importance to characterize biophysical properties of such complexes in detail.
Detection of dsDNA with [1,3]Dioxolo[4,5‐f]benzodioxol (DBD) Dyes
Authors: Büchner Dörthe , John Leonard , Mertens Monique , Wessig Pablo
Published: August 2018

DBD fluorescent dyes have proven to be useful in numerous applications. To widen the range of biological applications, we propose three different types of DBD molecules that have been modified in such a way that DNA interaction becomes probable. After the successful synthesis of all three compounds, we tested their fluorescent properties and their DNA binding abilities. Two of the three probes exhibit an interaction with dsDNA with subsequent fluorescence enhancement. The determined binding constants of the two new DNA dyes are comparable to other minor‐groove‐binding dyes. Their large Stokes shifts and their long fluorescent lifetimes are outstanding features of these dyes.
Supramolecular chirality transfer in a stereodynamic catalysts
Authors: Storch Golo , Trapp Oliver
Published: August 2018

We present rhodium catalysts that contain stereodynamic axially chiral biphenol‐derived phosphinite ligands modified with non‐stereoselective amides for non‐covalent interactions. A chirality transfer was achieved with (R)‐ or (S)‐acetylphenylalanine methyl amide, and the interaction mechanism was investigated by NMR measurements. These interactions at the non‐stereoselective interaction sites and the formation of supramolecular complexes result in an enrichment of either the (Rax)‐ or (Sax) enantiomer of the tropos catalysts, which in turn provide the (R)‐ or (S)‐acetylphenylalanine methyl ester in the hydrogenation of (Z)‐methyl‐α‐acetamidocinnamate.
Synthesis and Biological Evaluation of Reniochalistatins A–E and a Reniochalistatin E Analogue
Authors: Zhou Rong , Sun Yueguang , Li Hangbin , Long Weili , Liao Xiaojian , Feng Pengju , Xu Shihai
Published: August 2018

The total synthesis of reniochalistatins A–E, along with a reniochalistatin E analogue (inverso‐E) was successfully achieved through Fmoc‐based solid‐phase peptide synthesis and subsequent macrolactamization with PyBOP and DIEA. The biological activities of these reniochalistatins and a key linear peptide intermediate were systematically evaluated. Among these seven synthesized compounds, linear reniochalistatin B was found to have potent activity against several cancer cell lines not shown by the cyclic reniochalistatin B counterpart. In addition, linear reniochalistatin B was found to have antitubercular activity (IC50=1.4 μm). Inverso‐E possesses increasing cytotoxicity against the HeLa and LNCaP cell lines after simple alternation of the sequence of amino acids in reniochalistatin E. The results of these studies provide a feasible method to further investigate the structure–activity relationships (SARs) of reniochalistatins A–E.
Hot‐Injection Synthesized Ag2S Quantum Dots with Broad Light Absorption and High Stability for Solar Cell Applications
Authors: Öberg Viktor A. , Zhang Xiaoliang , Johansson Malin B. , Johansson Erik M. J.
Published: August 2018

A hot‐injection synthesis method was used to synthesize low‐toxicity Ag2S colloidal quantum dots (CQDs) with strong and broad light absorption as an ultra‐thin photo‐absorber in CQD heterojunction solar cells. By using iodide and sulfur linkers it was possible to accomplish efficient charge carrier extraction, resulting in a high photocurrent due to the broad absorption spectrum. Transient photovoltage decay measurements were used to obtain information about trap states in the CQDs and the effect on the lifetime of the photoinduced carriers. The devices show very promising stability under constant long‐term illumination and they are stable under ambient storage conditions with low losses to the performance over a period of over two months. These results show that Ag2S CQDs have high potential within solar cell applications, and point the direction for further improvements.
Recent Advances in Earth‐Abundant Photocathodes for Photoelectrochemical Water Splitting
Authors: Yang Wooseok , Moon Jooho
Published: August 2018

The conversion of solar energy into hydrogen through photoelectrochemical (PEC) water splitting is an attractive way to store renewable energy. Despite the intriguing concept of solar hydrogen production, efficient PEC devices based on earth‐abundant semiconductors should be realized to compete economically with conventional steam reforming processes. Herein, recent milestones in photocathode development for PEC water splitting, particularly in earth‐abundant semiconductors, in terms of new techniques for enhancing performance, as well as theoretical aspects, are highlighted. In addition, recent research into newly emerging low‐cost p‐type semiconductors in the PEC field, such as Cu2BaSn(S,Se)4 and Sb2Se3, are scrutinized and the advantages and disadvantages of each material assessed.
Lumped‐element filtering power dividers
Authors: Xiao Fei
Published: August 2018

A power divider is ideally a lossless reciprocal device performing vector summation of two or more input signals, which is an extremely important circuit component in wireless communication systems or radar systems. In this paper, a general concept of lumped‐element power divider is discussed. Then, a semi‐analytical synthesis technique is presented. General odd‐mode and even‐mode analysis method is proposed for multi‐port symmetrical network and applied in the analysis of N‐way lumped‐element power dividers. The transmission networks and the matching networks can be synthesized step by step, which greatly simplify their analysis. The transmission networks can be synthesized by those well‐known synthesis techniques for two‐port networks, and thus the transmission property of power dividers can be accurately controlled. The matching networks are determined by optimization to ensure certain isolation between the output ports. The design procedure is simple and accurate. Apart from the capability of power division, power dividers are also able to play the role of impedance transform and signal processing. Some examples of power dividers with filtering capability are presented for demonstration. In this paper, a general concept of lumped‐element power divider is discussed. Then, a semi‐analytical synthesis technique is presented. General odd‐mode and even‐mode analysis method is proposed for multi‐port symmetrical network and applied in the analysis of N‐way lumped‐element power dividers. Transmission networks and matching networks can be synthesized step by step, which greatly simplify their analysis. Apart from the capability of power division, power dividers are also able to play the role of impedance transform and signal processing.
TILAK: A token‐based prevention approach for topology discovery threats in SDN
Authors: Nehra Ajay , Tripathi Meenakshi , Gaur Manoj Singh , Battula Ramesh Babu , Lal Chhagan
Published: August 2018

Software‐defined networks (SDNs) decouple the data plane from the control plane. Thus, it provides logically centralized visibility of the entire networking infrastructure to the controller. It enables the applications running on top of the control plane to innovate through network management and programmability. To envision the centralized control and visibility, the controller needs to discover the networking topology of the entire SDN infrastructure. However, discovering and maintaining a global view of the underlying network topology is a challenging task because of (i) frequently changing network topology caused by migration of the virtual machines in the data centers, mobile, end hosts and change in the number of data plane switches because of technical faults or network upgrade; (ii) lack of authentication mechanisms and scarcity in SDN standards; and (iii) availability of security solutions during topology discovery process. To this end, the aim of this paper is threefold. First, we investigate the working methodologies used to achieve global view by different SDN controllers, specifically, POX, Ryu, OpenDaylight, Floodlight, Beacon, ONOS, and HPEVAN. Second, we identify vulnerabilities that affect the topology discovery process in the above controller implementation. In particular, we provide a detailed analysis of the threats namely link layer discovery protocol (LLDP) poisoning, LLDP flooding, and LLDP replay attack concerning these controllers. Finally, to countermeasure the identified risks, we propose a novel mechanism called TILAK which generates random MAC destination addresses for LLDP packets and use this randomness to create a flow entry for the LLDP packets. It is a periodic process to prevent LLDP packet‐based attacks that are caused only because of lack of verification of source authentication and integrity of LLDP packets. The implementation results for TILAK confirm that it covers targeted threats with lower resource penalty.
Paternal line effects of early experiences persist across three generations in rhesus macaques
Authors: Kinnally Erin L. , Gonzalez Mireille N. , Capitanio John P.
Published: August 2018

The effects of early stress may not be limited to the exposed generation, but are sometimes passed on to subsequent generations. Such non‐genetic transgenerational inheritance is a potentially important developmental and evolutionary force. We compared the transgenerational effects of maternal and paternal line early stress on anxiety‐ and health‐related traits in three non‐exposed generations (F1, F2 and F3) of semi‐naturalistically raised rhesus macaques. As infants, F0 macaques were exposed to nursery rearing (NR) or semi‐naturalistic social conditions (CONTROL). Three hundred forty non‐exposed F1–F3 descendants were CONTROL reared and physiological and behavioral measures were collected during standardized assessment at 3–4 months of age. Paternal line NR was significantly associated with greater nervousness in F1–F3 and lower immune cell counts in F1–F2. Maternal‐line NR effects were not observed. This study suggests that acquired stress‐related traits may be “inherited” across generations in primates, through complex social or germ‐line mechanisms.
Integration of students is key to success in higher ed, life
Authors: Sutton Halley
Published: August 2018

Edie Cusack, executive director of the REACH program at College of Charleston, a four‐year, fully inclusive certificate program for students with developmental disabilities, shared strategies for promoting full inclusion on your campus.
Identification of metabolites of evobrutinib in rat and human hepatocytes by using ultra‐high performance liquid chromatography coupled with diode array detector and Q Exactive Orbitrap tandem mass spectrometry
Authors: Li Zeyun , Zhang Lizhen , Yuan Yongliang , Yang Zhiheng
Published: August 2018

Evobrutinib is a highly selective inhibitor of Bruton's tyrosine kinase (BTK) which may be clinically effective in treating certain autoimmune diseases. The purpose of the present study was to investigate the metabolism of evobrutinib in rat and human hepatocytes. Evobrutinib was incubated with rat and human hepatocytes at 37°C for 2 hours after which the samples were analyzed by ultra‐high performance liquid chromatography with diode array detection and Q Exactive Orbitrap tandem mass spectrometry (UPLC–DAD–Q Exactive Orbitrap‐MS). The acquired data were processed by MetWorks™ software using mass effect filter and background subtraction functions. Under these conditions, 23 metabolites were detected and their identities proposed. Among these metabolites, M13 and M15 were identified by comparison of their retention times, accurate masses, and fragment ions with those of authentic reference standards. The metabolic pathways of evobrutinib were proposed accordingly. Our results demonstrated that evobrutinib was metabolized via hydroxylation, hydrolysis, O‐dealkylation, glucuronidation, and GSH conjugation. Species‐related metabolic differences between rat and human hepatocytes were observed. M1–M4 were rat‐specific metabolites. M13 (hydroxyl‐evobrutinib) was the major metabolite whereas M15 (evobrutinib‐diol) was a minor metabolite in rat hepatocytes. On the other hand, M6, M11, M16, M17, and M19 were human‐specific metabolites. M15 was the most abundant metabolite whereas M13 was the minor metabolite in human hepatocytes. This study provides preliminary information regarding the metabolism of evobrutinib that may be helpful in understanding the pharmacology of evobrutinib.
Single injection of ketamine during mid‐adolescence promotes long‐lasting resilience to activity‐based anorexia of female mice by increasing food intake and attenuating hyperactivity as well as anxiety‐like behavior
Authors: Chen Yi‐Wen , Sherpa Ang Doma , Aoki Chiye
Published: August 2018

Objective

This study tested the effects of ketamine on vulnerability of female adolescent mice to activity‐based anorexia (ABA).

Method

Twenty‐four female C57Bl/6 J mice underwent ABA induction, which involved exposing wheel‐acclimated adolescent mice to two bouts of food restriction (FR)—the first ABA (P41–44, mid‐adolescence) and the second ABA (P55–59, late adolescence), with recovery in between. Ketamine (3 or 30 mg/kg) or vehicle was given once, on the second day of FR of the first ABA (P42). Food consumption, body weight and wheel running activity were measured daily. Anxiety‐like behaviors were accessed by elevated plus maze on P49 and P62, after weight restoration during the recovery phase.

Results

Ketamine (30 mg/kg) increased food intake during the first ABA (+38%, p = .015) and facilitated weight gain during recovery (+42%, p = .003). During the second ABA, the effect was manifested as increased food intake (+38%, p = .001) and weight gain (+47%, p = .001) while attenuating FR‐induced wheel running activity (−24%, p = .09) and weight loss (−17%, p = .056). Ketamine also reduced anxiety‐like behaviors.

Discussion

Thus, single injection of ketamine during mid‐adolescence effectively attenuates vulnerability of female mice to repeated ABA exposures.
Drought and surface‐level solar radiation predict the severity of outbreaks of a widespread defoliating insect
Authors: Haynes Kyle J. , Tardif Jacques C. , Parry Dylan
Published: August 2018

Defoliating insects are a major factor impacting tree growth in temperate and boreal forests, but the effects of climate change on the severity and frequency of outbreaks of these insects are not well understood. Dendrochronological reconstruction of forest tent caterpillar (Malacosoma disstria) outbreaks on trembling aspen (Populus tremuloides) in southwestern Manitoba, Canada, from 1851 to 2010 was used to examine the effects of changes in temperature, incident surface‐level solar radiation, and drought severity on the cyclicity, frequency, and severity of outbreaks. Outbreak severity was determined by comparing the tree‐ring widths of trembling aspen with those of white spruce (Picea glauca), which is not a forest tent caterpillar host. Wavelet analysis suggested the cyclicity of outbreaks increased after 1930. From 1930 to 2010, the dominant period length of outbreak cycles steadily increased over time from three to seven years, coinciding with long‐term declines in drought severity. The strength of forest tent caterpillar suppression of trembling aspen growth in a given year was inversely related to incident solar radiation and drought severity during late spring (the larval feeding period) of the same year. The effect of late spring drought on the impact of forest tent caterpillar on ring growth differed from that of summer drought. There was a nonlinear relationship between growth suppression in a given year and summer drought severity in the previous year; slightly above‐average drought severity was associated with reduced impacts of the defoliator, whereas severe drought was associated with intense growth suppression. Strong suppression of aspen growth observed during outbreaks from 1983 to 2010 may be partly explained by observed long‐term trends of decreasing atmospheric transmittance of solar radiation (a phenomenon termed “global dimming”) and increasing soil moisture availability during late spring. However, as the severity and frequency of summer droughts are expected to increase over the 21st century, the nonlinear relationship between summer drought severity and growth suppression the following year suggests a future in which summer droughts precede severe outbreaks that threaten the health of boreal forest hardwood trees.
Updated distribution maps for neotropical bats in the superfamily Noctilionoidea
Authors: Rojas Danny , Moreira Matthew , Ramos Pereira Maria João , Fonseca Carlos , Dávalos Liliana M.
Published: August 2018

The IUCN provides a spatial database for many species, including terrestrial mammals. This database includes shapefiles with taxonomic information and the extent of occurrence for each species, and has been used in hundreds of studies in ecology, biogeography and conservation. Here we provide updated distribution maps that comprise the extent of occurrence of the neotropical bat species in the superfamily Noctilionoidea (Mammalia: Chiroptera) after a thorough research of new records published between January 2008 and March 2018. The main motivation for this update was the inclusion of spatial and climatic variables in explaining the ecological and taxonomic diversity of noctilionoid bats. The core of the superfamily (246 species distributed in five families out of 250 species) occurs in the Neotropics and shows ecological diversity unparalleled among mammals. This clade also shows the only evolutionary shift towards higher speciation rates within the order Chiroptera. Updating the range maps for these bats resulted in the modification of maps of 94 species, and the creation of new maps for 37 species missing from the IUCN database. From the 94 modified maps, 55 species increased their latitudinal range and 38 increased their longitudinal range. These modifications did not change the overall extent of occurrence of the clade. Altogether, modified and new maps represent 53% of Noctilionoidea. No copyright or proprietary restrictions are associated with the use of this data set other than citation of this Data Paper.
The total cost of misclassification in credit scoring: A comparison of generalized linear models and generalized additive models
Authors: Lohmann Christian , Ohliger Thorsten
Published: August 2018

This study examines whether the evaluation of a bankruptcy prediction model should take into account the total cost of misclassification. For this purpose, we introduce and apply a validity measure in credit scoring that is based on the total cost of misclassification. Specifically, we use comprehensive data from the annual financial statements of a sample of German companies and analyze the total cost of misclassification by comparing a generalized linear model and a generalized additive model with regard to their ability to predict a company's probability of default. On the basis of these data, the validity measure we introduce shows that, compared to generalized linear models, generalized additive models can reduce substantially the extent of misclassification and the total cost that this entails. The validity measure we introduce is informative and justifies the argument that generalized additive models should be preferred, although such models are more complex than generalized linear models. We conclude that to balance a model's validity and complexity, it is necessary to take into account the total cost of misclassification.
Intentional Design of the College Sophomore Year
Authors: Schaller Molly A.
Published: August 2018

This chapter makes the case that the sophomore year of college presents specific developmental challenges and, thus, opportunities for improved design of the college sophomore experience.
Institutional Policies that Impact Sophomore Success
Authors: Gahagan Jimmie
Published: August 2018

This chapter explores the way institutional policies and culture shape student success in the sophomore year.
Future Directions for Enhancing Sophomore Success
Authors: Schreiner Laurie A. , Schaller Molly A. , Young Dallin George
Published: August 2018

This chapter summarizes the recommendations from this volume and provides suggestions for future research and next steps in improving the sophomore‐year experience.
Stent grafts in patients with carotid blowout syndrome: Outcome and antiplatelet therapy in preventive versus emergency cases
Authors: Kreiser Kornelia , Gröber Isabell , Zimmer Claus , Storck Katharina
Published: August 2018

Background

Carotid blowout syndrome due to tumor infiltration, fistulas, and therapy‐related necrosis can occur as late as years after the treatment. Reporting our experiences with preventive and acute treatment with stent grafts and discussing different ways of antiplatelet therapy.

Methods

We reviewed all patients between 2010 and 2016 who underwent stent graft placement and analyzed outcome, complications, and antiplatelet regime.

Results

Seventeen patients were treated in 24 sessions (n = 7 threatened, n = 5 imminent, and n = 12 acute bleeding). The antiplatelet regime covered the entire range from aspirin only to loading doses of aspirin/clopidogrel, perioperative heparin, and aspirin/clopidogrel for 12 months followed by lifelong aspirin. Rare complications were not associated with the preprocedural or periprocedural but were associated with the postprocedural antiplatelet regime.

Conclusion

Most complications of stent graft implantations due to a carotid blowout syndrome occur postprocedurally: rare thrombotic events are linked to not taking a medication and frequent rebleedings may be reduced by an earlier reduction of dual‐antiplatelet to mono‐antiplatelet therapy.
Neoplastic Transformation of the Peribiliary Stem Cell Niche in Cholangiocarcinoma Arisen in Primary Sclerosing Cholangitis
Authors: Carpino Guido , Cardinale Vincenzo , Folseraas Trine , Overi Diletta , Grzyb Krzysztof , Costantini Daniele , Berloco Pasquale Bartolomeo , Di Matteo Sabina , Karlsen Tom Hemming , Alvaro Domenico , Gaudio Eugenio
Published: August 2018

Primary sclerosing cholangitis (PSC) is a chronic inflammatory cholangiopathy frequently complicated by cholangiocarcinoma (CCA). Massive proliferation of biliary tree stem/progenitor cells (BTSCs), expansion of peribiliary glands (PBGs), and dysplasia were observed in PSC. The aims of the present study were to evaluate the involvement of PBGs and BTSCs in CCA which emerged in PSC patients. Specimens from normal liver (n = 5), PSC (n = 20), and PSC‐associated CCA (n = 20) were included. Samples were processed for histology, immunohistochemistry, and immunofluorescence. In vitro experiments were performed on human BTSCs, human mucinous primary CCA cell cultures, and human cholangiocyte cell lines (H69). Our results indicated that all CCAs emerging in PSC patients were mucin‐producing tumors characterized by PBG involvement and a high expression of stem/progenitor cell markers. Ducts with neoplastic lesions showed higher inflammation, wall thickness, and PBG activation compared to nonneoplastic PSC‐affected ducts. CCA showed higher microvascular density and higher expression of nuclear factor kappa B, interleukin‐6, interleukin‐8, transforming growth factor β, and vascular endothelial growth factor‐1 compared to nonneoplastic ducts. CCA cells were characterized by a higher expression of epithelial‐to‐mesenchymal transition (EMT) traits and by the absence of primary cilia compared to bile ducts and PBG cells in controls and patients with PSC. Our in vitro study demonstrated that lipopolysaccharide and oxysterols (PSC‐related stressors) induced the expression of EMT traits, the nuclear factor kappa B pathway, autophagy, and the loss of primary cilia in human BTSCs. Conclusion: CCA arising in patients with PSC is characterized by extensive PBG involvement and by activation of the BTSC niche in these patients, the presence of duct lesions at different stages suggests a progressive tumorigenesis.
Influence of maternal exercise on fetal heart response during labor and delivery
Authors: McDonald Samantha , Satterfield Nichelle A. , May Linda E. , Newton Edward R. , Livingston Jeffrey , Fang Xiangming
Published: August 2018

Objectives

The purpose of this study was to determine if prenatal exercise alters the maternal and fetal heart responses during labor and delivery. We hypothesized that fetuses of exercising mothers would exhibit a lower baseline heart rate (HR), increased HR variability (HRV), and no differences in fetal heart accelerations and decelerations.

Design

This study employed a cross‐sectional design.

Methods

The Modifiable Physical Activity Questionnaire was used for group classification. Exercising women were those participating in 30 minutes of moderate‐to‐vigorous exercise at least 3×/week throughout the entire pregnancy. Women achieving a lower dose of exercise were classified as non‐exercisers. Cardiotocography recordings during the first hour of labor and delivery assessed fetal baseline HR, HRV, accelerations, decelerations, and contractions. ANCOVA analyses were performed to assess group differences in these outcomes and were adjusted for maternal body mass index.

Results

Thirty‐one women were included in the analyses. No group mean differences were found for maternal and fetal characteristics, except for maternal age (EX: mean (SD) 28.5 (±4.6y) vs NON‐EX: 24.1 (±1.2y)). After controlling for body mass index, no statistical differences in maternal HR response (β = 3.9, SE = 5.0, 95%CI −6.4‐14.2) or fetal HR response (β = 3.9, SE = 2.5, 95%CI −1.2‐9.11), accelerations and decelerations (β= −0.03, SE = 0.4, 95%CI −0.9‐0.8; β= −0.10, SE = 0.4, 95%CI −0.8‐0.9, respectively), or HRV (β = 0.6, SE = 1.7, 95%CI −2.8‐4.0) were observed.

Conclusions

Based on the findings of this study, we found no evidence that maternal exercise during pregnancy was associated with maternal or fetal HR response during labor and delivery. These data suggest maternal exercise may not elicit positive or negative effects on maternal and fetal cardiovascular responses to the physiological stress of labor and delivery.
Peer‐assisted location authentication and access control for wireless networks
Authors: Yuan Hu , Maple Carsten , Lu Yi , Watson Tim
Published: August 2018

This paper presents the development and implementation of a location‐based, lightweight peer‐assisted authentication scheme for use in wireless networks. The notion of peer‐assisted authentication is based upon some target user equipment‐ (UE) seeking authentication and access to a network based upon its physical location. The target UE seeks authentication through the UE of peers in the same network. Compared with previous work, the approach in this paper does not rely on any cryptographic proofs from a central authentication infrastructure, thus avoiding complex infrastructure management. However, the peer‐assisted authentication consumes network channel resources which will impact on network performance. In this paper, we also present an access control algorithm for balancing the location authentication, network quality of service (QoS), network capacity and time delay. The results demonstrate that peer‐assisted authentication considering location authentication and system QoS through dynamic access control strategies can be effectively and efficiently implemented in a number of use cases.