bluuebunny/crossref_metadata_2025 huggingface dataset:
Alcohol dehydrogenase III exacerbates liver fibrosis by enhancing stellate cell activation and suppressing natural killer cells in mice
Authors: Yi Hyon-Seung , Lee Young-Sun , Byun Jin-Seok , Seo Wonhyo , Jeong Jong-Min , Park Ogyi , Duester Gregg , Haseba Takeshi , Kim Sun Chang , Park Keun-Gyu , Gao Bin , Jeong Won-Il
Published: March 2014

The important roles of retinols and their metabolites have recently been emphasized in the interactions between hepatic stellate cells (HSCs) and natural killer (NK) cells. Nevertheless, the expression and role of retinol metabolizing enzyme in both cell types have yet to be clarified. Thus, we investigated the expression of retinol metabolizing enzyme and its role in liver fibrosis. Among several retinol metabolizing enzymes, only alcohol dehydrogenase (ADH) 3 expression was detected in isolated HSCs and NK cells, whereas hepatocytes express all of them. In vitro treatment with 4-methylpyrazole (4-MP), a broad ADH inhibitor, or depletion of the ADH3 gene down-regulated collagen and transforming growth factor-β1 (TGF-β1) gene expression, but did not affect α-smooth muscle actin gene expression in cultured HSCs. Additionally, in vitro, treatments with retinol suppressed NK cell activities, whereas inhibition of ADH3 enhanced interferon-γ (IFN-γ) production and cytotoxicity of NK cells against HSCs. In vivo, genetic depletion of the ADH3 gene ameliorated bile duct ligation- and carbon tetrachloride-induced liver fibrosis, in which a higher number of apoptotic HSCs and an enhanced activation of NK cells were detected. Freshly isolated HSCs from ADH3-deficient mice showed reduced expression of collagen and TGF-β1, but enhanced expression of IFN-γ was detected in NK cells from these mice compared with those of control mice. Using reciprocal bone marrow transplantation of wild-type and ADH3-deficient mice, we demonstrated that ADH3 deficiency in both HSCs and NK cells contributed to the suppressed liver fibrosis. Conclusion: ADH3 plays important roles in promoting liver fibrosis by enhancing HSC activation and inhibiting NK cell activity, and could be used as a potential therapeutic target for the treatment of liver fibrosis. (Hepatology 2014;60:1044–1053)
Truncated CXCL10 is associated with failure to achieve spontaneous clearance of acute hepatitis C infection
Authors: Riva Antonio , Laird Melissa , Casrouge Armanda , Ambrozaitis Arvydas , Williams Roger , Naoumov Nikolai V. , Albert Matthew L. , Chokshi Shilpa
Published: March 2014

The pathogenesis of hepatitis C virus (HCV) infection is strongly influenced by the nature of the host's antiviral immunity. Counterintuitively, elevated serum concentrations of C-X-C chemokine 10 (CXCL10), a potent chemoattractant for antiviral T-cells and NK-cells, are associated with poor treatment outcomes in patients with chronic HCV. It has been reported that an N-terminal truncated form of CXCL10, generated by the protease dipeptidylpeptidase 4 (DPP4), can act as chemokine antagonist. We sought to investigate CXCL10 antagonism in the clinical outcome and evolution of acute HCV infection. We collected serial blood samples from 16 patients, at the clinical onset of acute HCV infection and at 12 standardized follow-up timepoints over the first year. Intact and truncated CXCL10 and DPP4 activity were quantified in all longitudinal samples. In addition, NK-cell frequency/phenotype, and HCV-specific T-cell responses were assessed. Subjects developing chronicity (n = 11) had higher concentrations of CXCL10 (P < 0.001), which was predominantly in a truncated form (P = 0.036) compared to patients who spontaneously resolved infection (n = 5). Truncated CXCL10 correlated with HCV-RNA (r = 0.40, P < 0.001) and DPP4 activity (r = 0.53, P < 0.001). Subjects who resolved infection had a higher frequency of HCV-specific interferon-gamma (IFNγ)-producing T-cells (P = 0.017) and predominance of cytotoxic NK-cells (P = 0.005) compared to patients who became chronic. Patients who became persistently infected had higher proportions of cytokine-producing NK-cells, which were correlated with concentrations of truncated CXCL10 (r = 0.92, P < 0.001). Conclusion: This study provides the first evidence of chemokine antagonism during acute HCV infection. We suggest that the DPP4-CXCL10 axis inhibits antiviral innate and adaptive host immunity and favors establishment of viral persistence. (Hepatology 2014;60:487–496)
Hypercaloric diets with increased meal frequency, but not meal size, increase intrahepatic triglycerides: A randomized controlled trial
Authors: Koopman Karin E. , Caan Matthan W.A. , Nederveen Aart J. , Pels Anouk , Ackermans Mariette T. , Fliers Eric , la Fleur Susanne E. , Serlie Mireille J.
Published: March 2014

American children consume up to 27% of calories from high-fat and high-sugar snacks. Both sugar and fat consumption have been implicated as a cause of hepatic steatosis and obesity but the effect of meal pattern is largely understudied. We hypothesized that a high meal frequency, compared to consuming large meals, is detrimental in the accumulation of intrahepatic and abdominal fat. To test this hypothesis, we randomized 36 lean, healthy men to a 40% hypercaloric diet for 6 weeks or a eucaloric control diet and measured intrahepatic triglyceride content (IHTG) using proton magnetic resonance spectroscopy (1H-MRS), abdominal fat using magnetic resonance imaging (MRI), and insulin sensitivity using a hyperinsulinemic euglycemic clamp with a glucose isotope tracer before and after the diet intervention. The caloric surplus consisted of fat and sugar (high-fat-high-sugar; HFHS) or sugar only (high-sugar; HS) and was consumed together with, or between, the three main meals, thereby increasing meal size or meal frequency. All hypercaloric diets similarly increased body mass index (BMI). Increasing meal frequency significantly increased IHTG (HFHS mean relative increase of 45%; P = 0.016 and HS mean relative increase of 110%; P = 0.047), whereas increasing meal size did not (2-way analysis of variance [ANOVA] size versus frequency P = 0.03). Abdominal fat increased in the HFHS-frequency group (+63.3 ± 42.8 mL; P = 0.004) and tended to increase in the HS-frequency group (+46.5 ± 50.7 mL; P = 0.08). Hepatic insulin sensitivity tended to decrease in the HFHS-frequency group while peripheral insulin sensitivity was not affected. Conclusion: A hypercaloric diet with high meal frequency increased IHTG and abdominal fat independent of caloric content and body weight gain, whereas increasing meal size did not. This study suggests that snacking, a common feature in the Western diet, independently contributes to hepatic steatosis and obesity. (Trial registration: www.clinicaltrials.gov; nr.NCT01297738.) (Hepatology 2014;60:545–553)
Inactivation of protein‐phosphatase 2A causing hyperphosphorylation of autoantigenic paraprotein targets in MGUS/MM is due to an exchange of its regulatory subunits
Authors: Preuss Klaus‐Dieter , Fadle Natalie , Regitz Evi , Held Gerhard , Pfreundschuh Michael
Published: March 2014

Hyperphosphorylated paratarg‐7 (pP‐7) carrier state is the strongest molecularly defined risk factor for monoclonal gammopathy of undetermined significance (MGUS), multiple myeloma (MM) and Waldenstrom's macroglobulinemia (WM). pP‐7 is inherited as autosomal‐dominant trait and depending on the ethnic background is found in over one‐third of MGUS/MM patients. P‐7, which is the antigenic paraprotein target in these patients, is hyperphosphorylated at serine17. P‐7 hyperphosphorylation can be induced in wild‐type P‐7 (wtP‐7) carriers by PKCζ and reverted by protein‐phosphatase 2A (PP2A). Here we show that dephosphorylation of pP‐7 is defective in pP‐7 carriers due to inactivation of the PP2A by substitution of the regulatory B55δ subunit with B56γ3. In lymphoblastoid cell lines from pP‐7 carriers, transfection of recombinant B55δ or treatment with ceramide led to a partial reconstitution of PP2A activity and dephosphorylation of pP‐7 to wtP7. Similar results were observed with other previously reported autoantigenic paraproteins targets. In conclusion, the mechanisms responsible for the defective dephosphorylation and maintaining the hyperphosphorylated state of P‐7 and other autoantigenic paraprotein targets have been elucidated, facilitating the identification of the genetic basis underlying this phenomenon which is obviously common in the pathogenesis of MGUS/MM/WM and not restricted to pP‐7 cases.
SGI‐110 and entinostat therapy reduces lung tumor burden and reprograms the epigenome
Authors: Tellez Carmen S. , Grimes Marcie J. , Picchi Maria A. , Liu Yushi , March Thomas H. , Reed Matthew D. , Oganesian Aram , Taverna Pietro , Belinsky Steven A.
Published: March 2014

The DNA methyltransferase (DNMT) inhibitor vidaza (5‐Azacytidine) in combination with the histone deacetylase inhibitor entinostat has shown promise in treating lung cancer and this has been replicated in our orthotopic lung cancer model. However, the effectiveness of DNMT inhibitors against solid tumors is likely impacted by their limited stability and rapid inactivation by cytidine deaminase (CDA) in the liver. These studies were initiated to test the efficacy of SGI‐110, a dinucleotide containing decitabine that is resistant to deamination by CDA, as a single agent and in combination with entinostat. Evaluation of in vivo plasma concentrations and pharmacokinetic properties of SGI‐110 showed rapid conversion to decitabine and a plasma half‐life of 4 hr. SGI‐110 alone or in combination with entinostat reduced tumor burden of a K‐ras/p53 mutant lung adenocarcinoma cell line (Calu6) engrafted orthotopically in nude rats by 35% and 56%, respectively. SGI‐110 caused widespread demethylation of more than 300 gene promoters and microarray analysis revealed expression changes for 212 and 592 genes with SGI‐110 alone or in combination with entinostat. Epigenetic therapy also induced demethylation and expression of cancer testis antigen genes that could sensitize tumor cells to subsequent immunotherapy. In the orthotopically growing tumors, highly significant gene expression changes were seen in key cancer regulatory pathways including induction of p21 and the apoptotic gene BIK. Moreover, SGI‐110 in combination with entinostat caused widespread epigenetic reprogramming of EZH2‐target genes. These preclinical in vivo findings demonstrate the clinical potential of SGI‐110 for reducing lung tumor burden through reprogramming the epigenome.
The effect of geometry on tumor thermal profile and its use in tumor functional state estimation
Authors: Tepper Michal , Shoval Asaf , Gannot Israel
Published: March 2014

Thermal differences between transplanted tumors and tumors in humans prevent the implementation of thermographic methods developed in mice models to human models and vise‐versa. Transplantable tumors tend to have an extruding shape, which may affect the thermal patterns. This hypothesis was studied in phantom experiments and simulations. A correlation between tumor dimensions and relative temperature was found and used to estimate tumor functional state from previously published in vivo experiments. A correlation was found between temperature differences and tumor growth rates (tumor aggressiveness) and the effect of tumor treatment was demonstrated, showing the potential for in vivo, non‐invasive tumor monitoring. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)
Green Synthesis of Ag Nanoparticles by Callicarpa Maingayi: Characterization and Its Application with Graphene Oxide for Enzymeless Hydrogen Peroxide Detection
Authors: Chekin Fereshteh , Bagheri Samira , Abd Hamid Sharifah Bee
Published: March 2014

A facile green synthesis of silver nanoparticles (AgNPs) was achieved using aqueous leaf extract of Callicarpa Maingayi as a reducing and stabilizing agent during the synthesis from its salt solutions. The synthesized silver nanoparticles were analyzed with transmission electron microscopy (TEM), X‐ray diffraction (XRD) and energy dispersive spectrometer (EDS). XRD study shows that the particles are crystalline in nature with face centered cubic geometry. The crystallite size obtained from XRD is about 15 nm which is in agreement well with the TEM results. A new nanostructure sensor was constructed by immobilizing silver nanoparticles and graphene oxide (AgNPs‐GO) composite film on a glassy carbon electrode (AgNPs‐GO/GCE). It was found that the AgNPs‐GO composite exhibits good catalytic activity toward the reduction of hydrogen peroxide (H2O2), leading to an enzymeless sensor with a fast amperometric response time of less than 5 s, high selectivity, good reproducibility and stability. The linear range was 5.0 μM to 700 μM with a detection limit of 0.6 μM (S/N = 3).
Advancing safe drug use through interprofessional learning (IPL): A pilot study
Authors: Achike Francis I. , Smith John , Leonard Stuart , Williams Janet , Browning Felicia , Glisson James
Published: March 2014

Interprofessional collaborative patient‐centered care (IPCPC) improves healthcare quality and cost. Drug‐related morbidity drives healthcare costs, thus requiring IPCPC approaches. The lack of educational preparedness for would‐be IPCPC practitioners underlies the failure of historic IPCPC attempts, hence today's emphasis on pre‐licensure interprofessional education (IPE). A pilot IPE class was conducted on rational drug use (RDU) through rational drug prescribing. Twenty fourth‐year nursing students and 88 second‐year medical students participated (8–10 medical per 2–3 nursing students) in small group activity in a lecture hall. A case study on rational drug choice and prescription writing processes from medical and nursing perspectives was used. Eighty of 108 (74%) students completed the post‐activity questionnaire and were satisfied with the class, with a mean weighted score (mws) of 0.8. The learning outcomes (mws = 1.0) contributed more (P < 0.05) to students satisfaction than the organization/delivery (mws = 0.6). A majority (84–94%) agreed the class objectives were achieved and favored more classes. Interaction with other healthcare professionals and the crowded classroom were, respectively, the most‐ and least‐liked aspects of the class. The study revealed students' appetite for IPE, highlights the challenges in developing IPE curricula, and could serve as impetus for schools developing IPE for RDU curricula.
Electrochemical removal of tetrahydrofuran from industrial wastewaters: anode selection and process scale‐up
Authors: Urtiaga Ane , Gómez Pedro , Arruti Axel , Ortiz Inmaculada
Published: March 2014

BACKGROUND

In this work, industrial wastewaters with an average tetrahydrofuran (THF) concentration of 688 ± 140 mg L−1 were treated by electrooxidation. Four anodic materials were tested: RuO2, Pt, PbO2 and boron‐doped diamond (BDD). Bench scale experiments (volume treated 1 L, anode area 140 cm2) and pilot scale tests (volume treated 200 L, anode area 2800 cm2) were performed, and the influence of the applied current density, in the range 300 <japp <1200 A m−2, was assessed.

RESULTS

BDD was the only anodic material that enabled fast THF degradation and mineralization, using sodium sulfate as electrolyte. Dimensionally stable oxides such as RuO2 with sodium chloride as electrolyte did not achieve mineralization of the organic pollutants. Bench scale experiments allowed the kinetics of THF degradation to be described. The electrooxidation process, under mass transfer control, was enhanced by the contribution of electrogenerated secondary oxidants. The kinetic model and parameters used for the process scale up were fully validated by the excellent matching between the model predictions and the experimental results obtained at pilot scale.

CONCLUSIONS

The electrochemical treatment using BDD anodes allows the removal and mineralization of tetrahydrofuran contained in industrial wastewaters generated in rubber manufacturing. Process scale‐up, based on the kinetic model obtained from bench scale data, was successfully achieved. Energy consumption can be optimized by applying current modulation strategies. © 2014 Society of Chemical Industry
Removal of non‐steroidal anti‐inflammatory drugs from primary and secondary effluents in a photocatalytic membrane reactor
Authors: Darowna Dominika , Grondzewska Sara , Morawski Antoni W. , Mozia Sylwia
Published: March 2014

BACKGROUND

The pollution of the aquatic environment by pharmaceuticals has become a serious problem. Conventional technologies applied in water or sewage treatment plants are not effective in drugs removal, therefore there is an urgent need to develop new methods.

RESULTS

The removal of diclofenac (DCF), ibuprofen (IBU) and naproxen (NAP) sodium salts in a photocatalytic membrane reactor (PMR) utilizing direct contact membrane distillation and UV‐C radiation from ultrapure water, tap water, primary effluents (PE) and secondary effluents (SE) of municipal wastewater treatment plant is presented. When PE were used as feed and TiO2 loading of 0.5 g dm−3 was applied, DCF was removed completely, IBU amount decreased for 73% and NAP for 90%. In the case of SE, DCF, IBU and NAP concentrations decreased by 100%, 93% and 94%, respectively (1.5 gTiO2 dm−3). Mineralization was low and did not exceed 14% for PE and 23% for SE. No drugs were found in the distillate, however, it contained high level of N‐NH4+, especially in PE.

CONCLUSION

The hybrid system can be an effective technology for the removal of pharmaceuticals from SE and PE, however, owing to membrane fouling the latter should be pretreated before application in the PMR. © 2014 Society of Chemical Industry
Preference pulses without reinforcers
Authors: McLean Anthony P. , Grace Randolph C. , Pitts Raymond C. , Hughes Christine E.
Published: March 2014

Preference pulses are thought to represent strong, short‐term effects of reinforcers on preference in concurrent schedules. However, the general shape of preference pulses is substantially determined by the distributions of responses‐per‐visit (visit lengths) for the two choice alternatives. In several series of simulations, we varied the means and standard deviations of distributions describing visits to two concurrently available response alternatives, arranged “reinforcers” according to concurrent variable‐interval schedules, and found a range of different preference pulses. Because characteristics of these distributions describe global aspects of behavior, and the simulations assumed no local effects of reinforcement, these preference pulses derive from the visit structure alone. This strongly questions whether preference pulses should continue to be interpreted as representing local effects of reinforcement. We suggest an alternative approach whereby local effects are assessed by subtracting the artifactual part, which derives from visit structure, from the observed preference pulses. This yields “residual” preference pulses. We illustrate this method in application to published data from mixed dependent concurrent schedules, revealing evidence that the delivery of reinforcers had modest lengthening effects on the duration of the current visit, a conclusion that is quantitatively consistent with early research on short‐term effects of reinforcement.
The relative importance of climate change and shrub encroachment on nocturnal warming in the southwestern United States
Authors: He Yufei , D'Odorico Paolo , De Wekker Stephan F. J.
Published: March 2014

Many regions of the world are affected by a major land cover change resulting from the encroachment of woody plants and the conversion of grasslands into shrublands. In the southwestern United States, such a change in vegetation cover has been found to increase the winter nighttime temperature, thereby contributing to a positive feedback between shrub encroachment and microclimate in areas encroached by cold‐sensitive shrubs. Temperature measurements show that winter minimum temperatures are on average ∼2 K higher in shrubland than in adjacent grassland sites. It is unclear how the nighttime warming induced by shrub encroachment compares with regional climate trends. We address this question by analysing both the historical and future regional temperature trends in central New Mexico. The estimated regional increase in minimum winter temperature ranges from 1 to 4 K per century using observations and climate models. Thus, the warming resulting from shrub encroachment is equivalent to a change in regional climate over a time period of century scale, which suggests that shrub encroachment has an overall important effect on the regional climate.
Tunable graphene‐based plasmonic waveguides: nano modulators and nano attenuators
Authors: Lao Jieer , Tao Jin , Wang Qi Jie , Huang Xu Guang
Published: March 2014

A modulation principle and method, the gate‐voltage‐controlled mode‐guiding switching/mode‐cutoff mechanism, is proposed and numerically investigated to achieve the modulation/attenuation function. The propagating attenuation of the graphene 2D waveguide as a function of the Fermi level of the cladding is analyzed. Different modes with low or high attenuations in a wide attenuation range have been observed. The proposed structure avoids the patterning on graphene or substrate, thus diminishing the energy scattering on the edges. It also has the advantages of large modulation depth/attenuation range, wide bandwidth, and sub‐micrometer chip‐length with a nanoscale lateral section, which is promising for future graphene‐based integrated photonic devices.
Surface plasmon resonance tunability in VO2/Au/VO2 thermochromic structure
Authors: Zhou Huaijuan , Cao Xun , Jiang Meng , Bao Shanhu , Jin Ping
Published: March 2014

Nanometal–VO2 composite systems can exhibit a reversibly tunable localized surface plasmon effect under external temperature stimuli due to the temperature‐sensitive dielectric function of the thermochromic VO2 thin film. In order to improve the tunability range and enhance the resonance shift magnitude (ΔλSPR), the VO2/Au/VO2 sandwich structure was deliberately designed here. The plasmonic and thermochromic characteristics of this structure were powerfully dependent on the gold deposition time (t). By varying this parameter, the resonance wavelength (λSPR) of the semiconductor phase can be regulated from the visible range (686 nm) to the near‐infrared range (1482 nm) and a maximum ΔλSPR of 714 nm can be achieved at t = 3.5 min. This study may provide insights into plasmonic noble metal nanoparticles on a thermochromic VO2 matrix and offer potential applications in temperature‐sensitive nanodevices.
Hybrid photonic circuit for multiplexed heralded single photons
Authors: Meany Thomas , Ngah Lutfi A. , Collins Matthew J. , Clark Alex S. , Williams Robert J. , Eggleton Benjamin J. , Steel M. J. , Withford Michael J. , Alibart Olivier , Tanzilli Sébastien
Published: March 2014

A key resource for quantum optics experiments is an on‐demand source of single and multiple photon states at telecommunication wavelengths. This letter presents a heralded single photon source based on a hybrid technology approach, combining high efficiency periodically poled lithium niobate waveguides, low‐loss laser inscribed circuits, and fast (>1 MHz) fibre coupled electro‐optic switches. Hybrid interfacing different platforms is a promising route to exploiting the advantages of existing technology and has permitted the demonstration of the multiplexing of four identical sources of single photons to one output. Since this is an integrated technology, it provides scalability and can immediately leverage any improvements in transmission, detection and photon production efficiencies.
A nano‐plasmonic chip for simultaneous sensing with dual‐resonance surface‐enhanced Raman scattering and localized surface plasmon resonance
Authors: Lin Jiao , Zhang Yuan , Qian Jun , He Sailing
Published: March 2014

A dual‐resonance surface‐enhanced Raman scattering (SERS) chip which also serves as a localized surface plasmon resonance (LSPR) refractive index sensor is proposed. The dual‐resonance SERS chip can simultaneously enhance excitation and Stokes lines for Raman signals detection in a broad wavelength region with virtually no limitation. Thus, it is especially useful for Raman detection at long wave numbers and hyper Raman. The great performance of this chip relies on the highly independent tunability of the two localized plasmonic resonances from the optical to the near‐infrared region and the strict “hot spot” match in space for both resonant wavelengths. Furthermore, Raman signals of poly‐methyl‐methacrylate (PMMA) from 500 cm−1 to 3300 cm−1 are measured in the experiments and an obvious superiority can be seen compared to a single‐resonance SERS chip. In an addition, by using the subradiant magnetic dipole resonance, the LSPR refractive sensor gives a high sensitivity of 577 nm/RIU and high figure of merit (FoM) of 14.2. The experimental results are consistent with the simulated results. This dual‐functional sensing chip opens a route for dual‐modality detection of the concentration of some specific molecules.
The Renaissance of Side‐Chain Ferrocene‐Containing Polymers: Scope and Limitations of Vinylferrocene and Ferrocenyl Methacrylates
Authors: Gallei Markus
Published: March 2014

The synthesis of metal‐containing polymers and block copolymers has led to a rapidly expanding field of research interest for manifold potential applications. Within this contribution, some recent advances in the field of side‐chain ferrocene‐containing polymers focusing on poly(vinylferrocene) and poly(ferrocenyl methacrylates) are presented. The synthetic developments shown focus on living and controlled polymerizations, as well as surface‐initiated polymerization strategies. First attempts and recent developments for these novel redox‐responsive materials toward feasible applications are addressed.

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Poly(ethylene)‐co‐Poly(norborn‐2‐ene) Prepared by Group IV Bisamido and Half‐Sandwich Amido Complexes with Pendant Aminoborane Groups: Vinyl Insertion vs Ring‐Opening Metathesis Polymerization
Authors: Xu Guangjuan , Narayana Gurram Venkata , Speiser Maria , Wang Dongren , Zou Yuanlin , Buchmeiser Michael R.
Published: March 2014

A series of ZrIV and TiIV complexes containing the 6‐(2‐(diethylboryl)phenyl)pyridyl‐2‐yl motif are used in the methylalumoxane‐triggered copolymerization of ethylene (E) with norborn‐2‐ene (NBE). 13C NMR analyses reveal that vinyl insertion polymerization (VIP)‐derived poly(E)‐co‐poly(NBE) is obtained with pre‐catalysts 1–4 and 6, while pre‐catalyst 5 allows for the synthesis of a copolymer that contains both VIP‐ and ring‐opening metathesis polymerization (ROMP)‐derived structures. All the VIP‐derived poly(E)‐co‐poly(NBE) sequences show predominantly isolated NBE/alternating‐syndiotactic E‐NBE, as well as alternating‐isotactic E‐NBE sequences. The microstructure of the copolymers is correlated with the propensity of the pre‐catalysts to allow tandem ROMP‐VIP.

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Balancing the Initiation and Molecular Recognition Capabilities of Eosin Macroinitiators of Polymerization‐Based Signal Amplification Reactions
Authors: Lee Jungkyu K. , Sikes Hadley D.
Published: March 2014

Coupling polymerization initiators to molecular recognition events provide the ability to amplify these events and detect them using the formation of a cross‐linked polymer as an inexpensive readout that is visible to the unaided eye. The eosin‐tertiary amine co‐initiation system, activated by visible light, has proven utility in this context when an average of three eosin molecules are coupled to a protein detection reagent. The present work addresses the question of how detection sensitivity is impacted when the number of eosin molecules per binding event increases in the range of two to fifteen. Unlike in other initiation systems, a non‐monotonic relationship is observed between the number of initiators per binding event and the observed detection sensitivity.

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Reduction of Epoxidized Vegetable Oils: A Novel Method to Prepare Bio‐Based Polyols for Polyurethanes
Authors: Zhang Chaoqun , Ding Rui , Kessler Michael R.
Published: March 2014

A novel method, epoxidation/reduction of vegetable oils, is developed to prepare bio‐based polyols for the manufacture of polyurethanes (PUs). These polyols are synthesized from castor oil (CO), epoxidized soybean oil, and epoxidized linseed oil and their molecular structures are characterized. They are used to prepare a variety of PUs, and their thermomechanical properties are compared to those of PU made with petroleum‐based polyol (P‐450). It is shown that PUs made with polyols from soybean and linseed oil exhibit higher glass transition temperatures, tensile strength, and Young's modulus and PU made with polyol from CO exhibits higher elongation at break and toughness than PU made with P‐450. However, PU made with P‐450 displays better thermal resistance because of tri‐ester structure and terminal functional groups. The method provides a versatile way to prepare bio‐polyols from vegetable oils, and it is expected to partially or completely replace petroleum‐based polyols in PUs manufacture.

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Erratum: flow control in gas networks: exact controllability to a given demand
Authors: Gugat M. , Herty M. , Schleper V.
Published: March 2014

We correct a technical error in the paper of Gugat, Herty, Schleper, Math. Methods Appl. Sci. 34 (2011), where a framework for controllability of quasi–linear hyperbolic systems has been studied. The application to the case of gas networks is specified in more detail in the current work. Copyright © 2014 John Wiley & Sons, Ltd.
Im Schnee und durch den Schnee
Authors: Bartels‐Rausch Thorsten
Published: March 2014

Etwa die Hälfte der Landfläche in der nördlichen Hemisphäre ist im Winter schneebedeckt. Immer genauer versteht die Atmosphärenforschung die weitreichende Bedeutung der chemischen Prozesse im Schnee.
Im Internet gesucht, in der Nähe gefunden
Authors: Metzler‐Nolte Nils , Serova Katja
Published: March 2014

Die Aussagekraft von Rankings und ihre Bedeutung für die Wahl des Studienorts sind umstritten. Wie sich Chemiestudenten ihre Universität aussuchen und dass sie dabei sogar Rankings nutzen, die es gar nicht gibt, zeigt nun eine Studie von Bochumer Wissenschaftlern.
Butter aus Weidegras
Authors: Hopf Henning
Published: March 2014

Chemie und Film, 1. Mitteilung:

Cary Grant, hier als erfindungsreicher Chemiker, flirtet mit einer geradezu kindischen Marilyn Monroe, und Alec Guiness entwickelt eine Kunstfaser: Zwischen 1940 und 1960 gedreht, zeigen Kinofilme, wie das Wasserstoffbrückenkonzept Herzen gewinnt und Wissenschaft über Kapital geht.
Haustier geändert
Authors: Guggolz Ernst
Published: March 2014

Hat man schon jemals ein Hochhaus so schön zusammenkrachen sehen? Nicht nur die Sprengung eines universitären Turms in Frankfurt, sondern auch andere Kleinigkeiten gaben Anlass zu wilden Spekulationen und zu Erklärungen dessen, was die Welt zusammenhält — oder auseinanderfliegen lässt.
Schüler schalten chemisch
Authors: Schwarzer Stefan , Ingwersen Daniela , Herges Rainer , Parchmann Ilka
Published: March 2014

Wenn chemische Grundlagenforschung und Fachdidaktik zusammenarbeiten, profitieren beide Seiten. Ein Beispiel ist der Sonderforschungsbereich “Funktion durch Schalten” an der Universität Kiel, dessen Ergebnisse und Arbeitsweisen nun in Chemieunterricht und Schülerlabor einfließen.
Holding capacity of suction caisson anchors embedded in cohesive soils based on finite element analysis
Authors: Ahn Jaehun , Lee Hanmin , Kim Yun‐Tae
Published: March 2014

The foundations of offshore structures have been intensively studied to provide design guidelines for oil platforms. Recently, techniques developed for the oil industry have found new applications in the design of foundations for offshore wind turbines. There are simplified analytical solutions for the holding capacity of suction anchors, which are based on postulated failure mechanisms and are often compared with the results of finite element analyses. The merit of the results of a finite element analysis over the simplified solutions is that the finite element analysis satisfies all the basic equations in mechanics and does not require the assumption of reasonable failure mechanisms. The aim of this study is, based on the results of extensive finite element analyses, to provide a set of formulae for the estimation of the holding capacities of optimally loaded suction caisson anchors embedded in cohesive soils with a linear strength distribution. The bearing capacity factor and the depth of the optimal loading point are also estimated and reported. Copyright © 2014 John Wiley & Sons, Ltd.
Functional brain interactions during reflexive micturition are absent from spinal cord injured rats with neurogenic bladder
Authors: Wong Kelvin , Boone Timothy B. , Wong Stephen T.C. , Munoz Alvaro
Published: March 2014

Aims

The micturition reflex is initiated by urinary bladder distension triggering afferent pathways and activation of specific brain centers for controlling urine storage and release. We evaluated brain activation patterns using blood oxygenation level dependent functional magnetic resonance imaging (fMRI) during reflexive micturition in normal and spinal cord injury (SCI) rats.

Methods

Sprague‐Dawley female rats, either intact or with complete spinal cord transection, were anesthetized with urethane for simultaneous isovolumetric cystometry (CMG) and fMRI evaluations. A 9.4‐Tesla MRI system with a 4‐elements receiver array and a quadrature volume transmit coil was used to maximize the sensitivity detection. Gradient echo‐planar imaging (EPI) was used to evaluate brain activation during CMG compared to the empty bladder condition. Group analysis was conducted with a cluster threshold of Z > 2.5 and significance threshold of P = 0.05.

Results

The amplitude of bladder contractions was 10‐fold higher in control rats and inter‐contractile intervals were significantly shorter in SCI rats, indicative of neurogenic overactivity. Group analysis in intact rats showed both known and novel activation patterns in hippocampus, dentate gyrus, ectorhinal cortex, thalamic nucleus, septal nucleus, primary and secondary motor cortex, primary somatosensory cortex, and the periaqueductal gray matter. SCI rats did not exceed the Z‐threshold during CMG.

Conclusions

We standardized a suitable urodynamic protocol to study supraspinal activation during reflexive micturition using simultaneous CMG/fMRI with high spatial resolution. Small contractions in SCI rats may be caused by increased excitability of afferent pathways without brain activation. Our results represent the first fMRI study in SCI rats. Neurourol. Urodynam. 34:469–474, 2015. © 2014 Wiley Periodicals, Inc.
Self‐Aligned Selective Emitter Formation Using Commercial Screen‐Printed Contacts as a Plasma Etch Mask
Authors: Khandelwal Rahul , Windgassen Horst , Pletzer Tobias Markus , Kurz Heinrich
Published: March 2014

Selective emitter solar cells based on “screen‐printed” metallization face still several hurdles for the mass production in industry due to process complexities demanding advanced fabrication techniques and precise alignment of the final contact step. To address this issue, we present a simple and economical approach involving only a single diffusion and a plasma etching step to form the self‐aligned selective emitter (SASE) silicon solar cells. Particularly, a plasma etching step is used to reduce the thickness of homogeneous and heavily doped emitter, reducing doping concentration and thereby, increasing sheet resistance. In this paper, several distinctive characteristics of this cell concept are discussed such as; improved passivation quality of emitter by dry etching and electrical properties of screen‐printed contacts, which were used as mask during etch‐back process. Finally, a comparison of SASE solar cell with reference cells comprised of a standard homogeneous emitter is given. Since, there is no need for alignment in the selective emitter concept proposed, it appears to be an attractive solution for industrial cell fabrication.
Magnetic transitions and the magnetocaloric effect in the Pr1−xYxMn2Ge2 system
Authors: Wang J. L. , Campbell S. J. , Md Din M. F. , Kennedy S. J. , Hofmann M.
Published: March 2014

Layered rare earth compounds in the RMn2X2 series (R = rare‐earth; X = Ge, Si) are of interest for potential cooling applications at lower temperatures as they enable the structural and magnetic behavior to be controlled via substitution of R, Mn, and X atoms on the 2a, 4d, and 4e sites respectively. We continue investigations of the Pr1−xYxMn2Ge2 magnetic phase diagram as functions of both composition and Mn–Mn spacing using X‐ray and neutron diffraction, magnetization and differential scanning calorimetry measurements. Pr1−xYxMn2Ge2 exhibits an extended region of re‐entrant ferromagnetism around x ∼ 0.5 with re‐entrant ferromagnetism at for Pr0.5Y0.5Mn2Ge2. The entropy values −ΔSM around the ferromagnetic transition temperatures from the layered antiferromagnetic AFl structure to the canted ferromagnetic structure Fmc (typically ) have been derived for Pr1−xYxMn2Ge2 with x = 0.0, 0.2, and 0.5 for ΔB = 0–5 T. The changes in magnetic states due to Y substitution for Pr are discussed in terms of chemical pressure, external pressure, and electronic effects.
Anomalous temperature dependence of near‐infrared photoluminescence band in neutron‐irradiated α‐Al2O3
Authors: Rahman Abu Zayed Mohammad Saliqur , Wei Long , Yang Tao , Xu Qiu , Atobe Kozo
Published: March 2014

The properties of near‐infrared (NIR) photoluminescence (PL) spectra in a range of 0.8–2.8 μm in fast neutron‐irradiated α‐Al2O3 are reported. Anomalous temperature dependence of NIR PL spectra was observed in neutron‐irradiated α‐Al2O3 for the first time. Highest PL intensity was measured at 260 K whereas the intensity at low temperatures below 220 K decreased significantly. Phonon‐assisted indirect radiative recombination may be responsible for PL intensity enhancement at near room temperature. NIR PL band in a range of 0.8–2.8 μm may be well suited for application in broadly tunable color‐center laser because of its enhanced PL intensity at near room temperature.
Elucidation of electron ionization mass spectrometric fragmentation pathways of trimethylsilyl ether derivatives of vicinal diols deriving from haplamine by collision‐induced dissociation gas chromatography/tandem mass spectrometry and 18O labelling
Authors: Ea Sompheary , Aubert Claude , Rontani Jean‐François , Teral Yannick , Campredon Mylène
Published: March 2014

RATIONALE

Formation of vicinal diols was observed after in vitro and in vivo studies of the natural product haplamine (9‐methoxy‐2,2‐dimethyl‐2,6‐dihydropyrano[3,2‐c]quinolin‐5‐one). These compounds, identified as trans‐ and cis‐3,4‐dihydroxy‐9‐methoxy‐2,2‐dimethyl‐2,3,4,6‐tetrahydropyrano[3,2‐c]quinolin‐5‐ones and trans‐ and cis‐3,4,9‐trihydroxy‐2,2‐dimethyl‐2,3,4,6‐tetrahydropyrano[3,2‐c]quinolin‐5‐ones, have a potential interest in oncology. It is therefore essential to elucidate their electron ionization mass spectrometric (EIMS) fragmentation pathways.

METHODS

EIMS fragmentation pathways of trimethylsilyl (TMS) derivatives of 3,4‐dihydroxy‐ and 3,4,9‐trihydroxyhaplamines were investigated. These pathways have been substantiated by: (i) comparison with EI mass spectra of structural homologues (silylated diols obtained from various chromenes and 1,2‐dihydronaphthalene), (ii) low‐energy collision‐induced dissociation (CID) gas chromatography/tandem mass spectrometry (GC/MS/MS) and (iii) 18O labelling.

RESULTS

CID‐MS/MS analyses and 18O labelling demonstrated that EI mass spectral fragmentation of these TMS derivatives involves a transannular cleavage of the pyran ring with formation of a characteristic intense cyclic ion. The study of the mass spectra of TMS derivatives of different chromenes and 1,2‐dihydroxynaphthalene allowed to confirm the proposed fragmentation pathways and to show that they act only when the pyran ring is present.

CONCLUSIONS

Elimination of the neutral element [(CH3)2=C(H)OSi(CH3)3] and formation of cyclic ions play a key role during EI mass spectral fragmentation of the TMS derivatives of 3,4‐dihydroxy‐ and 3,4,9‐trihydroxyhaplamines. These fragmentation pathways could be generalized to TMS derivatives of cyclic compounds possessing vicinal diols close to a pyran ring. Copyright © 2014 John Wiley & Sons, Ltd.
A mixture of transition models for heterogeneous longitudinal ordinal data: with applications to longitudinal bacterial vaginosis data
Authors: Cheon Kyeongmi , Thoma Marie E. , Kong Xiangrong , Albert Paul S.
Published: March 2014

Markov models used to analyze transition patterns in discrete longitudinal data are based on the limiting assumption that individuals follow the common underlying transition process. However, when one is interested in diseases with different disease or severity subtypes, explicitly modeling subpopulation‐specific transition patterns may be appropriate. We propose a model which captures heterogeneity in the transition process through a finite mixture model formulation and provides a framework for identifying subpopulations at different risks. We apply the procedure to longitudinal bacterial vaginosis study data and demonstrate that the model fits the data well. Further, we show that under the mixture model formulation, we can make the important distinction between how covariates affect transition patterns unique to each of the subpopulations and how they affect which subgroup a participant will belong to. Practically, covariate effects on subpopulation‐specific transition behavior and those on subpopulation membership can be interpreted as effects on short‐term and long‐term transition behavior. We further investigate models with higher‐order subpopulation‐specific transition dependence. Copyright © 2014 John Wiley & Sons, Ltd.
Selective Detection of Target Proteins by Peptide‐Enabled Graphene Biosensor
Authors: Khatayevich Dmitriy , Page Tamon , Gresswell Carolyn , Hayamizu Yuhei , Grady William , Sarikaya Mehmet
Published: March 2014

Direct molecular detection of biomarkers is a promising approach for diagnosis and monitoring of numerous diseases, as well as a cornerstone of modern molecular medicine and drug discovery. Currently, clinical applications of biomarkers are limited by the sensitivity, complexity and low selectivity of available indirect detection methods. Electronic 1D and 2D nano‐materials such as carbon nanotubes and graphene, respectively, offer unique advantages as sensing substrates for simple, fast and ultrasensitive detection of biomolecular binding. Versatile methods, however, have yet to be developed for simultaneous functionalization and passivation of the sensor surface to allow for enhanced detection and selectivity of the device. Herein, we demonstrate selective detection of a model protein against a background of serum protein using a graphene sensor functionalized via self‐assembling multifunctional short peptides. The two peptides are engineered to bind to graphene and undergo co‐assembly in the form of an ordered monomolecular film on the substrate. While the probe peptide displays the bioactive molecule, the passivating peptide prevents non‐specific protein adsorption onto the device surface, ensuring target selectivity. In particular, we demonstrate a graphene field effect transistor (gFET) biosensor which can detect streptavidin against a background of serum bovine albumin at less than 50 ng/ml. Our nano‐sensor design, allows us to restore the graphene surface and utilize each sensor in multiple experiments. The peptide‐enabled gFET device has great potential to address a variety of bio‐sensing problems, such as studying ligand‐receptor interactions, or detection of biomarkers in a clinical setting.
An Empirical Study on Critical Factors Affecting Employee Satisfaction
Authors: Shan Siqing , Li Cangyan , Yao Wei , Shi Jihong , Ren Jie
Published: March 2014

With the rapid development of information technology (IT), IT service quality has become a popular topic in both academic circles and enterprises. Based on the literature, the factors influencing employee satisfaction in Lenovo Group were studied. In terms of users in IT enterprises, a comprehensive evaluation index system of employee satisfaction was established based on a survey and a thorough data analysis. Using the structural equation modelling method, the critical factors affecting employee satisfaction and their interrelationships are identified. This method has practical value and can be used as a reference for employee satisfaction measurement and management in IT service enterprises. Copyright © 2014 John Wiley & Sons, Ltd.
Impact of Effective Communication, Achievement Sharing and Positive Classroom Environments on Learning Performance
Authors: Shan Siqing , Li Cangyan , Shi Jihong , Wang Li , Cai Huali
Published: March 2014

Finding a way to improve students' learning performance is a crucial concern in education reform. Many researchers have investigated possible predictors of student learning performance, including personality traits, learning styles, self‐efficacy, and so on. Nevertheless, there is limited research that examines the effectiveness of the interaction between students and teachers, achievement sharing, and the classroom environment. This study investigates the impact of effective communication between students and teachers, achievement sharing, and a positive classroom environment on learning performance through an empirical analysis. We found that when teachers create a sense of community, respond to students and foster positive relationships, students are more engaged and enthusiastic about learning and tend to perform better academically. Copyright © 2014 John Wiley & Sons, Ltd.
Pax3 and Tbx5 Specify Whether PDGFRα+ Cells Assume Skeletal or Cardiac Muscle Fate in Differentiating Embryonic Stem Cells
Authors: Magli Alessandro , Schnettler Erin , Swanson Scott A. , Borges Luciene , Hoffman Kirsta , Stewart Ron , Thomson James A. , Keirstead Susan A. , Perlingeiro Rita C. R.
Published: March 2014

Embryonic stem cells (ESCs) represent an ideal model to study how lineage decisions are established during embryonic development. Using a doxycycline-inducible mouse ESC line, we have previously shown that expression of the transcriptional activator Pax3 in early mesodermal cells leads to the robust generation of paraxial mesoderm progenitors that ultimately differentiate into skeletal muscle precursors. Here, we show that the ability of this transcription factor to induce the skeletal myogenic cell fate occurs at the expenses of the cardiac lineage. Our results show that the PDGFRα+FLK1− subfraction represents the main population affected by Pax3, through downregulation of several transcripts encoding for proteins involved in cardiac development. We demonstrate that although Nkx2–5, Tbx5, and Gata4 negatively affect Pax3 skeletal myogenic activity, the cardiac potential of embryoid body-derived cultures is restored solely by forced expression of Tbx5. Taking advantage of this model, we used an unbiased genome-wide approach to identify genes whose expression is rescued by Tbx5, and which could represent important regulators of cardiac development. These findings elucidate mechanisms regulating the commitment of mesodermal cells in the early embryo and identify the Tbx5 cardiac transcriptome. Stem Cells  2014;32:2072–2083