bluuebunny/crossref_metadata_2025_split huggingface dataset:
N‐Methylformamid undN‐Methylacetamid in Urin [Biomonitoring Methods in German Language, 2015]
Authors: Will W. , Göen T. , Hartwig A. ,   MAK Commission
Published: July 2016

AbstractThe present method allows for the determination of the main metabolites of N,N‐dimethylformamide and N,N‐dimethylacetamide in urine: HMMF, NMF, HMMA and NMA, respectively. HMMF and HMMA readily decompose thermally to form N‐methylformamide (NMF) or N‐methylacetamide (NMA) and formaldehyde. Prior to sample injection, thermolysis is carried out for 2 hours at 120°C in order to transform the metabolites completely into the target analytes NMF and NMA. The urine samples are then diluted with ethanol and analyzed using GC–MS. Thus, the sum of HMMF and NMF (DMF metabolites) and the sum of HMMA and NMA (DMA metabolites), respectively, are detected by this procedure.
Arsenic and its Inorganic Compounds (with the Exception of Arsine) [MAK Value Documentation, 2014]
Authors: Hartwig A. ,   MAK Commission
Published: July 2016

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated arsenic and its inorganic compounds, with a special focus on gallium arsenide. Available publications and study reports are described in detail.Arsenic and its inorganic compounds are carcinogenic in humans. From the available studies in workers in the semiconductor industry probably exposed to gallium arsenide, no increased cancer risk can be derived. Carcinogenicity studies with inhalation exposure to gallium arsenide revealed lung tumours, mononuclear leukaemia and benign phaeochromocytomas in the adrenal glands in female rats. In animal studies, increased levels of arsenic in blood were determined after exposure to gallium arsenide. The metabolites are the same as those found after exposure to arsenite and arsenate. Although the bioavailability of gallium arsenide is much lower than that of arsenic trioxide, it cannot be completely neglected. Therefore, the classification of arsenic and its inorganic compounds including gallium arsenide as carcinogenic in man (Carcinogen Category 1) has been retained.In vitro genotoxicity studies with inorganic arsenic(III) compounds yielded mostly positive results in tests for sister chromatid exchange, chromosomal aberrations and micronuclei. In in vivo studies with somatic cells, arsenic(III) compounds induced an increase in DNA strand breaks, chromosomal aberrations and micronuclei. In humans exposed long‐term to arsenic, increased incidences of micronuclei, chromosomal aberrations, sister chromatid exchange and DNA damage were observed. Gallium arsenide was not genotoxic in vitro and in vivo. Gallium arsenide, like arsenic, is systemically available and forms the same metabolites as arsenic and its inorganic compounds. For this reason the suspected germ cell mutagenicity of gallium arsenide cannot be unequivocally excluded. Arsenic and its inorganic compounds including gallium arsenide therefore remain in Category 3A for germ cell mutagens which produce mutagenic effects in somatic cells of mammals in vivo and have been shown to reach the germ cells.No MAK value has been derived and thus also no peak limitation has been established, and classification into one of the Pregnancy Risk Groups is not possible. Skin contact is not expected to contribute significantly to systemic toxicity. Sensitizing effects of arsenic and its inorganic compounds cannot be derived from the available data.
Visibly‐Transparent Organic Solar Cells on Flexible Substrates with All‐Graphene Electrodes
Authors: Song Yi , Chang Sehoon , Gradecak Silvija , Kong Jing 
Published: July 2016

Portable electronic devices have become increasingly widespread. Because these devices cannot always be tethered to a central grid, powering them will require low‐cost energy harvesting technologies. As a response to this anticipated demand, this study demonstrates transparent organic solar cells fabricated on flexible substrates, including plastic and paper, using graphene as both the anode and cathode. Optical transmittance of up to 69% at 550 nm is achieved by combining the highly transparent graphene electrodes with organic polymers that primarily absorb in the near‐IR and near‐UV regimes. To address the challenge of transferring graphene onto organic layers as the top electrode, this study develops a room temperature dry‐transfer technique using ethylene‐vinyl‐acetate as an adhesion‐promoting interlayer. The power conversion efficiency achieved for flexible devices with graphene anode and cathode devices is 2.8%–3.8% at for optical transmittance of 54%–61% across the visible regime. These results demonstrate the versatility of graphene in optoelectronic applications and it is important step toward developing a practical power source for distributed wireless electrical systems.
Structurally rigid bis(pyrazolyl)pyridine Zn(II) and Cu(II) complexes: Structures and kinetic studies in ring‐opening polymerization of ε‐caprolactone
Authors: Zikode Mnqobi , Ojwach Stephen O. , Akerman Matthew P. 
Published: July 2016

Four bis(pyrazolyl)pyridine Zn(II) and Cu(II) carboxylate complexes have been structurally elucidated and used as initiators in the ring‐opening polymerization (ROP) of ε‐carprolactone (ε‐CL). Reactions of bis(3,5‐dimethyl‐pyrazol‐1‐yl)pyridine (L1) with the appropriate Zn(II) and Cu(II) carboxylates afforded the corresponding complexes; [Zn(L1)(C6H5COO)2] (1), [Zn(L1)(2‐Cl‐C6H4COO)2] (2), [Zn(L1)(OAc)2] (3) and [Cu(L1)(OAc)2] (4) in moderate to good yields. Molecular structures of compounds 1, 2, 3 confirmed the presence of one tridentate bound ligand L1 in the metal coordination sphere and two carboxylate anions to give five coordination number around Zn(II) and Cu(II) atoms. Complexes 1, 2, 3, 4 initiated the ROP of ε‐CL at 110 °C to give polymers of moderate molecular weights. Kinetic analyses of the ROP reactions indicate pseudo‐first‐order dependency on ε‐CL monomer and initiator. 1H NMR and mass spectral data established a coordination insertion mechanistic pathway and behaviour of 1, 2, 3, 4 as initiators in the ROP of ε‐CL. Copyright © 2016 John Wiley & Sons, Ltd.
Improved Robust Stability Criteria for Time‐Delay Lur'e System
Authors: Duan Wenyong , Fu Xiaorong , Liu Zhengfan , Yang Xiaodong 
Published: July 2016

AbstractThis paper deals with the problem of the robustly absolute stability for neutral‐type Lur'e systems with mixed time‐varying delay. By combining the piecewise analysis theory with the reciprocally convex method and Wirtinger‐based inequality technology, some new delay‐dependent stability criteria are proposed via a modified Lyapunov‐Krasovskii functional (LKF) approach. The stability conditions can be solved by using standard linear matrix inequality (LMI) convex optimization solvers. The criteria are less conservative than some previous ones. Three numerical examples are presented to show the effectiveness of the proposed approach.
Inflating transform matrices to mitigate assimilation errors with robust filtering based ensemble Kalman filters
Authors: Bai Yulong , Zhang Zhuanhua , Zhang Yanli , Wang Lili 
Published: July 2016

AbstractAn error covariance matrix plays an important role in maintaining the statistical property of the ensemble in an ensemble Kalman filter method. However, data assimilation filter divergence may occur from an inaccurate estimate of the covariance matrix. In this study, based on an ensemble time‐local H‐infinity filter, which inflates the eigenvalues of the analysis error covariance matrix, a new robust ensemble data assimilation method is proposed, referred to as an inflation transform matrix eigenvalues. By design, new filters may be preferred over other traditional ensemble filters, when model performances are not well known, or change unpredictably. The primary aim is to improve the performance of the assimilation system in the framework of the ensemble filtering, according to the minimum/maximum rule of robust filtering. The proposed estimation method is tested using the well‐known Lorenz‐96 model, in order to investigate how the ensemble time‐local H‐infinity filter method of the inflation transform matrix impacts the robustness of the assimilation system under selected special conditions, such as the assimilation steps, force parameters, ensemble sizes, and observation information. The experiments show that the proposed inflation transform matrix method displays good robustness to the changes in the system's parameters. Also, when compared with the traditional filtering methods, this robust filtering method is found to improve the assimilation performance.
Enhanced integration of large DNA into E. coli chromosome by CRISPR/Cas9
Authors: Chung Mu‐En , Yeh I‐Hsin , Sung Li‐Yu , Wu Meng‐Ying , Chao Yun‐Peng , Ng I‐Son , Hu Yu‐Chen 
Published: July 2016

ABSTRACTMetabolic engineering often necessitates chromosomal integration of multiple genes but integration of large genes into Escherichia coli remains difficult. CRISPR/Cas9 is an RNA‐guided system which enables site‐specific induction of double strand break (DSB) and programmable genome editing. Here, we hypothesized that CRISPR/Cas9‐triggered DSB could enhance homologous recombination and augment integration of large DNA into E. coli chromosome. We demonstrated that CRISPR/Cas9 system was able to trigger DSB in >98% of cells, leading to subsequent cell death, and identified that mutagenic SOS response played roles in the cell survival. By optimizing experimental conditions and combining the λ‐Red proteins and linear dsDNA, CRISPR/Cas9‐induced DSB enabled homologous recombination of the donor DNA and replacement of lacZ gene in the MG1655 strain at efficiencies up to 99%, and allowed high fidelity, scarless integration of 2.4, 3.9, 5.4, and 7.0 kb DNA at efficiencies approaching 91%, 92%, 71%, and 61%, respectively. The CRISPR/Cas9‐assisted gene integration also functioned in different E. coli strains including BL21 (DE3) and W albeit at different efficiencies. Taken together, our methodology facilitated precise integration of dsDNA as large as 7 kb into E. coli with efficiencies exceeding 60%, thus significantly ameliorating the editing efficiency and overcoming the size limit of integration using the commonly adopted recombineering approach. Biotechnol. Bioeng. 2017;114: 172–183. © 2016 Wiley Periodicals, Inc.
Identification and Structural Analysis of New Nrf2 Activators by Mechanism‐Based Chemical Transformation of 15‐Deoxy‐Δ12, 14‐PGJ2
Authors: Kim Kyeojin , Park Jong‐Min , Kim Nam‐Jung , Kim Su‐Jung , Moon Hyunyoung , An Hongchan , Lee Jeeyeon , Park Hyun‐Ju , Surh Young‐Joon , Suh Young‐Ger 
Published: July 2016

AbstractMechanism‐based chemical transformation of 15‐deoxy‐Δ12, 14‐PGJ2 (15d‐PGJ2) resulted in a series of new NF‐E2‐related factor‐2 (Nrf2) activators and detailed elucidation of the function of each electrophilic binding site. In addition, HO‐1 expression resulting from Nrf2 activation through enhanced dissociation of the Keap1–Nrf2 complex by the new activators was proved.
Cryopreserved hepatic progenitor cells derived from human embryonic stem cells can arrest progression of liver fibrosis in rats
Authors: Mandal Arundhati , Raju Sheena , Viswanathan Chandra 
Published: July 2016

AbstractHepatocytes generated from human embryonic stem cells (hESCs) are considered to be an excellent candidate for restoring the liver function deficiencies. We have earlier standardized a three‐step differentiation protocol to generate functional hepatocyte‐like cells (HLCs) from hESCs, which expressed the major hepatic markers. We have also found that the HLCs remain stable and functional even after extended period of in vitro culture and cryopreservation. In the present study, we have aimed to investigate the therapeutic potential of cryopreserved‐thawed hESC‐derived hepatic progenitor cells following transplantation in carbon tetrachloride‐induced fibrotic rat livers. Significant therapeutic effects, including improved hepatic histology and normal serum biochemistry of hepatic enzymes along with increased survival rate, were observed in the cell transplanted rats. This result is an encouraging indication to develop methods for clinical application of hESC‐derived hepatic lineage cells.
Rab proteins as regulators of lipid droplet formation and lipolysis
Authors: Li Chunman , Yu Sidney S. B. 
Published: July 2016

AbstractLipid droplets (LDs) are highly dynamic organelles that not only store neutral lipids but also are involved in multiple cellular processes. Dysregulation of lipogenesis or lipolysis greatly contributes to the pathogenesis of several human diseases, including obesity, diabetes, and fatty liver disease. Rab proteins have been found to be associated with LDs in proteomic studies and are also known to extensively regulate intracellular membrane traffic, suggesting that LDs actively communicate with other membrane compartments to maintain energy homeostasis. This review discusses recent studies that provide mechanistic insights into the regulation of LD formation and catabolism by Rab proteins in mammalian cells.
An Efficient Electrocatalyst Derived from Bamboo Leaves for the Oxygen Reduction Reaction
Authors: Zhang Lian Ying , Zhou Zhiqin , Liu Ze , Li Chang Ming 
Published: July 2016

AbstractBamboo leaves are carbonized and tailored into an efficient electrocatalyst as an alternative to noble‐metal‐based catalysts of oxygen reduction. Surprisingly, in comparison to the commercial Pt/C, the as‐prepared catalyst shows higher methanol tolerance, resistance to CO poisoning and stability, and similar electrocatalytic activity. The high electrocatalytic activity probably arises from the hierarchical porous structure for fast mass transport and its inherently existing N, S or Fe as efficient catalytic sites. This work offers a facile approach to use inexpensive biomass as a promising and inexpensive electrocatalyst material in fuel cell applications, and suggests a performance‐enhancement mechanism for the biomass‐derived catalyst.
Fault diagnosis of chemical processes considering fault frequency via Bayesian network
Authors: Askarian Mahdieh , Zarghami Reza , Jalali‐Farahani Farhang , Mostoufi Navid 
Published: July 2016

ABSTRACTIn the present study, data‐driven fault diagnosis (FD) systems of chemical plants dealing with frequent and rare faults are investigated. Although different faults occur with different frequencies in chemical plants, this issue has scarcely been addressed in developing a process FD system. A novel diagnostic framework based on the Bayesian network (BN) is proposed to incorporate fault frequencies. This probabilistic method can readily involve non‐uniform probability distribution of faults and non‐Gaussian probability distribution of features. The proposed approach includes not only a combination of tools but also information management. In fact, the imbalanced dataset, established by frequent and rare faults, promotes recursive updating of prior probabilities of faults. The performance of the BN was evaluated and compared with the conventional C4.5 method in the Tennessee‐Eastman process benchmark. It was shown in this work that the diagnostic performance of the proposed approach versus the C4.5 method is more efficient. The importance of taking into account non‐uniform probability distribution of faults for designing a FD system was highlighted. Furthermore, the effect of independent component analysis (ICA) of the imbalanced dataset on the FD was examined. The proposed framework versus the C4.5 method promises 37 % FD performance improvement for the dataset with a 10:1 imbalance index.
Tailored Combination of Low Dimensional Catalysts for Efficient Oxygen Reduction and Evolution in Li–O2 Batteries
Authors: Yoon Ki Ro , Kim Dae Sik , Ryu Won‐Hee , Song Sung Ho , Youn Doo‐Young , Jung Ji‐Won , Jeon Seokwoo , Park Yong Joon , Kim Il‐Doo 
Published: July 2016

AbstractThe development of efficient bifunctional catalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is a key issue pertaining high performance Li–O2 batteries. Here, we propose a heterogeneous electrocatalyst consisting of LaMnO3 nanofibers (NFs) functionalized with RuO2 nanoparticles (NPs) and non‐oxidized graphene nanoflakes (GNFs). The Li–O2 cell employing the tailored catalysts delivers an excellent electrochemical performance, affording significantly reduced discharge/charge voltage gaps (1.0 V at 400 mA g−1), and superior cyclability for over 320 cycles. The outstanding performance arises from (1) the networked LaMnO3 NFs providing ORR/OER sites without severe aggregation, (2) the synergistic coupling of RuO2 NPs for further improving the OER activity and the electrical conductivity on the surface of the LaMnO3 NFs, and (3) the use of GNFs providing a fast electronic pathway as well as improved ORR kinetics.
Isolation‐induced vocalization in the infant rat depends on the nucleus accumbens
Authors: Muller Jeff M. , Shair Harry N. 
Published: July 2016

AbstractMammalian infants vocalize when socially isolated. Vocalization guides the return of the caregiver and thereby maintains an environment critical to the infant's survival. Although the role of the periaqueductal gray area (PAG) in these vocalizations is established, other aspects of the relevant neural circuitry remain under‐studied. Here we report that output from the nucleus accumbens (Acb) is necessary for isolation‐induced vocalizations of infant rats aged postnatal days (PND) 11–13. Local inhibition via infusion of the GABAA agonist muscimol (.8 μg/side) of the Acb, but not the dorsolateral striatum, blocked isolation‐induced vocalizations, independent of whether the isolation was at room temperature, followed a brief reunion with the dam, or occurred in a cool (10 °C) environment. These findings highlight a possible anatomical area mediating the mammalian infant response to social separation and, more generally, to the development of social attachment.
Sex and seasonal differences in hippocampal volume and neurogenesis in brood‐parasitic brown‐headed cowbirds (Molothrus ater)
Authors: Guigueno Mélanie F. , MacDougall‐Shackleton Scott A. , Sherry David F. 
Published: July 2016

ABSTRACTBrown‐headed cowbirds (Molothrus ater) are one of few species in which females show more complex space use than males. Female cowbirds search for, revisit, and parasitize host nests and, in a previous study, outperformed males on an open field spatial search task. Previous research reported a female‐biased sex difference in the volume of the hippocampus, a region of the brain involved in spatial memory. Neurons produced by adult neurogenesis may be involved in the formation of new memories and replace older neurons that could cause interference in memory. We tested for sex and seasonal differences in hippocampal volume and neurogenesis of brood‐parasitic brown‐headed cowbirds and the closely related non‐brood‐parasitic red‐winged blackbird (Agelaius phoeniceus) to determine whether there were differences in the hippocampus that reflected space use in the wild. Females had a larger hippocampus than males in both species, but hippocampal neurogenesis, measured by doublecortin immunoreactivity (DCX+), was greater in female than in male cowbirds in the absence of any sex difference in blackbirds, supporting the hypothesis of hippocampal specialization in female cowbirds. Cowbirds of both sexes had a larger hippocampus with greater hippocampal DCX+ than blackbirds. Hippocampus volume remained stable between breeding conditions, but DCX+ was greater post‐breeding, indicating that old memories may be lost through hippocampal reorganization following breeding. Our results support, in part, the hypothesis that the hippocampus of cowbirds is specialized for brood parasitism. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 76: 1275–1290, 2016
A short synthesis of siloxane phosphocholines
Authors: Frampton Mark B. , Zelisko Paul M. 
Published: July 2016

Herein, we report our first generation synthesis of two new silicon‐containing phosphocholines (SiPCs) in which the fatty acid chains are terminated by trisiloxane units. We have been exploring the limits to which immobilized lipases can be used in the field of organosilicon chemistry, and the cornerstone of this work is a chemoenzymatic approach to synthesizing SiPCs that are structurally analogous to naturally occurring species such as 1‐palmitoyl‐2‐oleoyl‐sn‐glycero‐3‐phosphocholine (POPC).Practical applications: This research focuses on the chemoenzymatic synthesis of siloxane‐containing phospholipid systems. These compounds have different surface properties than the comparable biologically relevant phospholipids opening the doors for the potential application of these siloxane‐containing species as encapsulation/delivery vehicles and as a means of modifying surfaces.Surface pressure‐molecular area isotherms for siloxane‐phospholipids.
A Facile and Cost‐effective Electroanalytical Strategy for the Quantification of Deoxyguanosine and Deoxyadenosine in Oligonucleotides Using Screen‐printed Graphite Electrodes
Authors: Brotons Ariadna , Sanjuán Ignacio , Foster Christopher W. , Banks Craig E. , Vidal‐Iglesias Francisco José , Solla‐Gullón José , Iniesta Jesús 
Published: July 2016

AbstractThe development of electroanalytical methods for the detection and quantification of nucleotides in DNA offers vital implications in assessing the degree of oxidation or epigenetic modification in DNA. Unfortunately, the electrochemical response of oligonucleotides is strongly influenced by the size, composition and nucleic base sequence. In this article, an optimized analytical procedure for the enzymatically breakdown of the oligonucleotides to their corresponding nucleotides for the evaluation of the electrochemical response through the use of square wave voltammetry (SWV) is presented. Enzymatic digestion of oligonucleotides has been optimized in terms of buffer composition, digestion time, strategy for stopping the enzymatic reaction and filtration requirement for enzyme removal, and then compared to an established protocol. Under the optimized protocol SWV response of a number of untreated and enzymatically digested six‐mer oligonucleotides, namely 5′‐GGGGGG‐3′, 5′‐AAAAAA‐3′, 5′‐CGCGCG‐3′ and 5′‐AAACGC‐3′ have been analysed, providing a higher sensitivity for the determination of guanosine and adenosine monophosphate species under digestion conditions with a more facile and cost effective procedure. The novel strategy for the enzymatically treated oligonucleotides in combination with the SWV response provides a proof of principle for feasible applications in the diagnosis of methylated guanosine in DNA as a potential biomarker due to its relation with cancer.