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Sample records for gapa efficiently inhibits

  1. The role of glyceraldehyde 3-phosphate dehydrogenase (GapA-1 in Neisseria meningitidis adherence to human cells

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    Wooldridge Karl G

    2010-11-01

    Full Text Available Abstract Background Glyceraldehyde 3-phosphate dehydrogenases (GAPDHs are cytoplasmic glycolytic enzymes, which although lacking identifiable secretion signals, have also been found localized to the surface of several bacteria (and some eukaryotic organisms; where in some cases they have been shown to contribute to the colonization and invasion of host tissues. Neisseria meningitidis is an obligate human nasopharyngeal commensal which can cause life-threatening infections including septicaemia and meningitis. N. meningitidis has two genes, gapA-1 and gapA-2, encoding GAPDH enzymes. GapA-1 has previously been shown to be up-regulated on bacterial contact with host epithelial cells and is accessible to antibodies on the surface of capsule-permeabilized meningococcal cells. The aims of this study were: 1 to determine whether GapA-1 was expressed across different strains of N. meningitidis; 2 to determine whether GapA-1 surface accessibility to antibodies was dependant on the presence of capsule; 3 to determine whether GapA-1 can influence the interaction of meningococci and host cells, particularly in the key stages of adhesion and invasion. Results In this study, expression of GapA-1 was shown to be well conserved across diverse isolates of Neisseria species. Flow cytometry confirmed that GapA-1 could be detected on the cell surface, but only in a siaD-knockout (capsule-deficient background, suggesting that GapA-1 is inaccessible to antibody in in vitro-grown encapsulated meningococci. The role of GapA-1 in meningococcal pathogenesis was addressed by mutational analysis and functional complementation. Loss of GapA-1 did not affect the growth of the bacterium in vitro. However, a GapA-1 deficient mutant showed a significant reduction in adhesion to human epithelial and endothelial cells compared to the wild-type and complemented mutant. A similar reduction in adhesion levels was also apparent between a siaD-deficient meningococcal strain and an

  2. Global Advocacy for Physical Activity (GAPA): global leadership towards a raised profile.

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    Blanchard, Claire; Shilton, Trevor; Bull, Fiona

    2013-12-01

    Physical inactivity has been recognised by the World Health Organization as one of the leading causes of death due to non-communicable disease (NCD), worldwide. The benefits of action over inactivity can cut across health, environment, transportation, sport, culture and the economy. Despite the evidence, the policies and strategies to increase population-wide participation in physical activity receive insufficient priority from across high, middle and low-income countries; where physical inactivity is a rapidly-emerging issue. There is an increased need for all countries to invest in policies, strategies and supportive environments that inform, motivate and support individuals and communities to be active in ways that are safe, accessible and enjoyable. This commentary presents some recent efforts towards physical activity promotion globally, led by the Global Advocacy for Physical Activity (GAPA). It provides an overview of the background and history of GAPA; describes GAPA and the council's key achievements and milestones; places physical activity promotion within the global NCD agenda; presents GAPA flagships; and reflects on the lessons learned, ingredients for success and the major challenges that remain. The commentary documents insights into the effectiveness and challenges faced by a small non-governmental organisation (NGO) in mounting global advocacy. These lessons may be transferrable to other areas of health promotion advocacy.

  3. Anxiety, inhibition, efficiency, and effectiveness. An investigation using antisaccade task.

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    Derakshan, Nazanin; Ansari, Tahereh L; Hansard, Miles; Shoker, Leor; Eysenck, Michael W

    2009-01-01

    Effects of anxiety on the antisaccade task were assessed. Performance effectiveness on this task (indexed by error rate) reflects a conflict between volitional and reflexive responses resolved by inhibitory processes (Hutton, S. B., & Ettinger, U. (2006). The antisaccade task as a research tool in psychopathology: A critical review. Psychophysiology, 43, 302-313). However, latency of the first correct saccade reflects processing efficiency (relationship between performance effectiveness and use of resources). In two experiments, high-anxious participants had longer correct antisaccade latencies than low-anxious participants and this effect was greater with threatening cues than positive or neutral ones. The high- and low-anxious groups did not differ in terms of error rate in the antisaccade task. No group differences were found in terms of latency or error rate in the prosaccade task. These results indicate that anxiety affects performance efficiency but not performance effectiveness. The findings are interpreted within the context of attentional control theory (Eysenck, M. W., Derakshan, N., Santos, R., & Calvo, M. G. (2007). Anxiety and cognitive performance: Attentional control theory. Emotion, 7 (2), 336-353).

  4. The effect of perceptual load on attention-induced motion blindness: the efficiency of selective inhibition.

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    Hay, Julia L; Milders, Maarten M; Sahraie, Arash; Niedeggen, Michael

    2006-08-01

    Recent visual marking studies have shown that the carry-over of distractor inhibition can impair the ability of singletons to capture attention if the singleton and distractors share features. The current study extends this finding to first-order motion targets and distractors, clearly separated in time by a visual cue (the letter X). Target motion discrimination was significantly impaired, a result attributed to the carry-over of distractor inhibition. Increasing the difficulty of cue detection increased the motion target impairment, as distractor inhibition is thought to increase under demanding (high load) conditions in order to maximize selection efficiency. The apparent conflict with studies reporting reduced distractor inhibition under high load conditions was resolved by distinguishing between the effects of "cognitive" and "perceptual" load. ((c) 2006 APA, all rights reserved).

  5. Efficient inhibition of HIV-1 replication by an artificial polycistronic miRNA construct

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    Zhang Tao

    2012-06-01

    Full Text Available Abstract Background RNA interference (RNAi has been used as a promising approach to inhibit human immunodeficiency virus type 1 (HIV-1 replication for both in vitro and in vivo animal models. However, HIV-1 escape mutants after RNAi treatment have been reported. Expressing multiple small interfering RNAs (siRNAs against conserved viral sequences can serve as a genetic barrier for viral escape, and optimization of the efficiency of this process was the aim of this study. Results An artificial polycistronic transcript driven by a CMV promoter was designed to inhibit HIV-1 replication. The artificial polycistronic transcript contained two pre-miR-30a backbones and one pre-miR-155 backbone, which are linked by a sequence derived from antisense RNA sequence targeting the HIV-1 env gene. Our results demonstrated that this artificial polycistronic transcript simultaneously expresses three anti-HIV siRNAs and efficiently inhibits HIV-1 replication. In addition, the biosafety of MT-4 cells expressing this polycistronic miRNA transcript was evaluated, and no apparent impacts on cell proliferation rate, interferon response, and interruption of native miRNA processing were observed. Conclusions The strategy described here to generate an artificial polycistronic transcript to inhibit viral replication provided an opportunity to select and optimize many factors to yield highly efficient constructs expressing multiple siRNAs against viral infection.

  6. Synthesis, characterization and corrosion inhibition efficiency of N-(4-(Morpholinomethyl Carbamoyl Phenyl Furan-2-Carboxamide

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    N. Zulfareen

    2016-01-01

    Full Text Available A mannich base namely N-(4-(Morpholinomethyl Carbamoyl Phenyl Furan-2-Carboxamide (MFC was synthesized and characterized by FT-IR, 1H NMR, and 13C NMR. The molecular weight of MFC was confirmed by LC-MS. The inhibition effect of MFC on brass in 1 M HCl medium has been investigated by weight loss measurement, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS and cyclic voltametry (CV. Thermodynamic parameters such as free energy, entropy and enthalpy were calculated to describe the mechanism of corrosion inhibitor. The inhibition efficiency of MFC increases with increase in concentration and temperature ranges from 30 °C to 60 °C. Polarization measurements indicated that MFC acts as a mixed type corrosion inhibitor. AC impedance indicates that Rct value increases with increase in the concentration of inhibitor. CV reveals that the oxidation of the copper is controlled by the addition of inhibitor on the brass metal. Surface analysis using scanning electron microscope (SEM shows a significant morphological improvement on the brass surface with the addition of the inhibitor. The adsorption of MFC on brass obeys Langmuir adsorption isotherm. The molecular structure of MFC was distorted to quantum chemical indices using density functional theory (DFT which indicates that the inhibition efficiency of MFC is closely related to quantum parameters.

  7. Electrochemical evaluation of inhibition efficiency of ciprofloxacin on the corrosion of copper in acid media

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    Thanapackiam, P. [Department of Chemistry, Coimbatore Institute of Technology, Coimbatore, Tamilnadu, 641 014 (India); Rameshkumar, Subramaniam [Department of Chemistry, Sri Vasavi College, Erode, Tamilnadu, 638 316 (India); Subramanian, S.S. [Department of Chemistry, PSG College of Technology, Coimbatore, Tamilnadu, 641 004 (India); Mallaiya, Kumaravel, E-mail: mkvteam.research@gmail.com [Department of Chemistry, PSG College of Technology, Coimbatore, Tamilnadu, 641 004 (India)

    2016-05-01

    The inhibition efficiency of ciprofloxacin on the corrosion of copper was studied in 1.0MHNO{sub 3} and 0.5MH{sub 2}SO{sub 4} solutions by electrochemical impedance spectroscopy and potentiodynamic polarization techniques. The corrosion inhibition action of ciprofloxacin was observed to be of mixed type in both the acid media, but with more of a cathodic nature. The experimental data were found to fit well with the Langmuir adsorption isotherm. The thermodynamic parameters such as adsorption equilibrium constant(K{sub ads}), free energy of adsorption(ΔG{sub ads}), activation energy(E{sub a}) and potential of zero charge(PZC) showed that the adsorption of ciprofloxacin onto copper surface involves both physisorption and chemisorption. - Highlights: • The inhibitor efficiency increases with increase in ciprofloxacin concentration. • Polarization measurements show that ciprofloxacin acts as a mixed type inhibitor. • The adsorption of the inhibitor on copper surface follows Langmuir adsorption isotherm. • The negative values of ΔG{sub ads} indicates that the adsorption is spontaneous and exothermic.

  8. A bi-paratopic anti-EGFR nanobody efficiently inhibits solid tumour growth

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    Roovers, Rob C.; Vosjan, Maria J.W.D.; Laeremans, Toon; el Khoulati, Rachid; de Bruin, Renée C.G.; Ferguson, Kathryn M.; Verkleij, Arie J.; van Dongen, Guus A.M.S.; van Bergen en Henegouwen, Paul M. P.

    2014-01-01

    The epidermal growth factor receptor (EGFR) has been shown to be a valid cancer target for antibody-based therapy. At present, several anti-EGFR monoclonal antibodies (mAbs) have been successfully used, among which cetuximab and matuzumab. X-ray crystallography data show that these antibodies bind to different epitopes on the ecto-domain of EGFR, providing a rationale for the combined use of these two antibody specificities. We have previously reported on the successful isolation of antagonistic anti-EGFR nanobodies. In the present study, we aimed to improve on these molecules by combining nanobodies with specificities similar to both cetuximab and matuzumab into a single bi-paratopic molecule. Carefully designed phage nanobody selections resulted in two sets of nanobodies that specifically blocked the binding of either matuzumab or of cetuximab to EGFR and that did not compete for each others binding. A combination of nanobodies from both epitope groups into the bi-paratopic nanobody CONAN-1 was shown to block EGFR activation more efficiently than monovalent or bivalent (monospecific) nanobodies. In addition, this bi-paratopic nanobody potently inhibited EGF-dependent cell proliferation. Importantly, in an in vivo model of athymic mice bearing A431 xenografts, CONAN-1 inhibited tumour outgrowth with an almost similar potency as the whole mAb cetuximab, despite the fact that CONAN-1 is devoid of an Fc portion that could mediate immune effector functions. Compared to therapy using bivalent, mono-specific nanobodies, CONAN-1 was clearly more potent in tumour growth inhibition. These results show that the rational design of bi-paratopic nanobody-based anti-cancer therapeutics may yield potent lead molecules for further development. PMID:21520037

  9. Curcumin modified silver nanoparticles for highly efficient inhibition of respiratory syncytial virus infection

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    Yang, Xiao Xi; Li, Chun Mei; Huang, Cheng Zhi

    2016-01-01

    Interactions between nanoparticles and viruses have attracted increasing attention due to the antiviral activity of nanoparticles and the resulting possibility to be employed as biomedical interventions. In this contribution, we developed a very simple route to prepare uniform and stable silver nanoparticles (AgNPs) with antiviral properties by using curcumin, which is a member of the ginger family isolated from rhizomes of the perennial herb Curcuma longa and has a wide range of biological activities like antioxidant, antifungal, antibacterial and anti-inflammatory effects, and acts as reducing and capping agents in this synthetic route. The tissue culture infectious dose (TCID50) assay showed that the curcumin modified silver nanoparticles (cAgNPs) have a highly efficient inhibition effect against respiratory syncytial virus (RSV) infection, giving a decrease of viral titers about two orders of magnitude at the concentration of cAgNPs under which no toxicity was found to the host cells. Mechanism investigations showed that cAgNPs could prevent RSV from infecting the host cells by inactivating the virus directly, indicating that cAgNPs are a novel promising efficient virucide for RSV.Interactions between nanoparticles and viruses have attracted increasing attention due to the antiviral activity of nanoparticles and the resulting possibility to be employed as biomedical interventions. In this contribution, we developed a very simple route to prepare uniform and stable silver nanoparticles (AgNPs) with antiviral properties by using curcumin, which is a member of the ginger family isolated from rhizomes of the perennial herb Curcuma longa and has a wide range of biological activities like antioxidant, antifungal, antibacterial and anti-inflammatory effects, and acts as reducing and capping agents in this synthetic route. The tissue culture infectious dose (TCID50) assay showed that the curcumin modified silver nanoparticles (cAgNPs) have a highly efficient inhibition

  10. Inclusion of the helper lipid dioleoyl-phosphatidylethanolamine in solid lipid nanoparticles inhibits their transfection efficiency.

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    de Jesus, Marcelo B; Radaic, Allan; Hinrichs, Wouter L J; Ferreira, Carmen V; de Paula, Eneida; Hoekstra, Dick; Zuhorn, Inge S

    2014-02-01

    Solid lipid nanoparticles (SLNs) are a promising system for the delivery of lipophilic and hydrophilic drugs. They consist of a solid lipid core that is stabilized by a layer of surfactants. By the incorporation of cationic lipids in the formulation, positively charged SLNs can be generated, that are suitable carriers for nucleic acids (DNA, siRNA). Considering the beneficial effect of helper lipids on the transfection efficiency with cationic liposomes, the effect of the helper lipid 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) on transfection with cationic lipid-containing solid lipid nanoparticles was investigated in PC3 prostate cancer cells. The inclusion of DOPE in SLN formulations, instead of promoted, strongly inhibited SLN transfection efficiency, by frustrating the accommodation of DNA by the particles, as was revealed by biochemical analysis. SLNs devoid of DOPE maintained a homogenous size distribution of approximately 150 nm following lipoplex assembly and cellular delivery, and showed transfection efficiency comparable to that of Lipofectamine 2000' (LF2k). Moreover, the SLNs maintain their high transfection efficiency after lyophilization and long-term storage (1-2 years), an important asset for biomedical applications. There is even the possibility to lyophilize the SLN carrier together with its DNA cargo, which represents an interesting pharmaceutical advantage of the SLN formulations over LF2k. These results reflect marked differences between the physicochemical properties of cationic liposomes and SLNs, the latter requiring more critical lipid-depending properties for effective 'packaging' of DNA but displaying a higher storage stability than cationic lipid based carriers like LF2k.

  11. Study on Corrosion Inhibition Efficiency of Stem Alkaloid Extract of Different Varieties of Holy Basil on Aluminium in HCl Solution

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    Kumpawat, Nutan; Chaturvedi, Alok; Upadhyay, R. K. [Synthetic and Surface Science Laboratory, Ajmer (India)

    2012-08-15

    Corrosion inhibition efficiencies of holy basil on Al in HCl solution were studied by weight loss and thermometric methods in presence and in absence of stem extract of three different varieties of holy basil viz. ocimum basilicum (E{sub B}), ocimum canum (E{sub C}) and ocimum sanctum (E{sub S}). Inhibition efficiency increases with the increasing concentration of stem extract and decreases with increases in acid strength. Results show that all varieties under study are good corrosion inhibitors, among which, E{sub B} is most effective. Maximum inhibition efficiency was found 97.09% in 0.5N HCl solution with 0.6% stem extract. The Langmuir adsorption isotherm indicates that surface coverage also increases with increasing in the concentration of extract of stem in HCl solution.

  12. Age-Related Deficits in Efficiency of Low-Level Lateral Inhibition

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    Friederike eSchlaghecken

    2012-04-01

    Full Text Available In a masked prime task using a 0-ms prime-target inter-stimulus-interval, responses on compatible trials (prime and target match are usually faster and more accurate than responses on incompatible trials (prime-target mismatch. This positive compatibility effect comprises benefits on compatible relative to neutral trials and costs on incompatible relative to neutral trials. Comparing performance in 2- vs. 4-alternative-response versions of the task indicates that benefits are due to direct priming of a motor response, whereas costs reflect inhibition of the alternative response tendency. The present study investigates whether normal aging is associated with a selective deficit in the inhibitory component, affecting both low-level motor and higher-level executive control. Testing 20 young and 20 older adults, we found that (a overall, prime-induced benefits were of similar magnitude across age groups, but inhibition-based costs were smaller in older compared to young adults; (b increasing the number of response alternatives caused the same pattern of unaltered benefits and reduced costs in both age groups; and (c costs, but not benefits, in the 2-alternative condition were significantly predicted by scores on the digit-symbol substitution task (DSST, independently of age and other background variables. Results demonstrate the possibility of isolating an inhibitory component in low-level perceptuo-motor control. Importantly, this component shows an age-related decline in the absence of a corresponding decline of visuo-motor excitability, and appears to be linked to performance on a higher-level processing speed task. We hypothesize that aging might affect the brain's ability to establish precise short-term lateral inhibitory links, and that even in young adults, the efficiency of such links is a significant contributing factor in higher-level cognitive performance.

  13. Highly efficient inhibition of human immunodeficiency virus type 1 reverse transcriptase by aptamers functionalized gold nanoparticles

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    Shiang, Yen-Chun; Ou, Chung-Mao; Chen, Shih-Ju; Ou, Ting-Yu; Lin, Han-Jia; Huang, Chih-Ching; Chang, Huan-Tsung

    2013-03-01

    We have developed aptamer (Apt)-conjugated gold nanoparticles (Apt-Au NPs, 13 nm in diameter) as highly effective inhibitors for human immunodeficiency virus type 1 reverse transcriptase (HIV-1 RT). Two Apts, RT1t49 (Aptpol) and ODN 93 (AptRH), which recognize the polymerase and RNase H regions of HIV-1 RT, are used to conjugate Au NPs to prepare Aptpol-Au NPs and AptRH-Au NPs, respectively. In addition to DNA sequence, the surface density of the aptamers on Au NPs (nApt-Au NPs; n is the number of aptamer molecules on each Au NP) and the linker length number (Tm; m is the base number of the deoxythymidine linker) between the aptamer and Au NPs play important roles in determining their inhibition activity. A HIV-lentiviral vector-based antiviral assay has been applied to determine the inhibitory effect of aptamers or Apt-Au NPs on the early stages of their replication cycle. The nuclease-stable G-quadruplex structure of 40AptRH-T45-Au NPs shows inhibitory efficiency in the retroviral replication cycle with a decreasing infectivity (40.2%).We have developed aptamer (Apt)-conjugated gold nanoparticles (Apt-Au NPs, 13 nm in diameter) as highly effective inhibitors for human immunodeficiency virus type 1 reverse transcriptase (HIV-1 RT). Two Apts, RT1t49 (Aptpol) and ODN 93 (AptRH), which recognize the polymerase and RNase H regions of HIV-1 RT, are used to conjugate Au NPs to prepare Aptpol-Au NPs and AptRH-Au NPs, respectively. In addition to DNA sequence, the surface density of the aptamers on Au NPs (nApt-Au NPs; n is the number of aptamer molecules on each Au NP) and the linker length number (Tm; m is the base number of the deoxythymidine linker) between the aptamer and Au NPs play important roles in determining their inhibition activity. A HIV-lentiviral vector-based antiviral assay has been applied to determine the inhibitory effect of aptamers or Apt-Au NPs on the early stages of their replication cycle. The nuclease-stable G-quadruplex structure of 40AptRH-T45

  14. Organic compounds as corrosion inhibitors for mild steel in acidic media: correlation between inhibition efficiency and chemical structure

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    Elias, Elizandra C.S.; Chrisman, Erika C.A.N. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil). Escola de Quimica

    2009-12-19

    The use of inhibitors for mild steels corrosion control which are in contact with aggressive environment is an accepted practice in acid treatment of oil-wells. Organic compounds have been studied to evaluate their corrosion inhibition potential. Film-forming corrosion inhibitors, commonly used to protect oil-field equipment, can be absorbed on the steel surface to give structurally ordered layers. Therefore, the electrons should act as an important role for this adsorption. Studies reveal that organic compounds show significant inhibition efficiency. For this purpose, their molecules should contain N, O and S heteroatoms in various functional groups, long hydrocarbon linear or branched radical and anion and cation active components. However, most of these compounds are not only expensive but also toxic to living beings. According to the 'Green Chemistry' rules, corrosion inhibitors based on organic compounds should be cheap, with low toxicity and have high inhibition efficiency. In this study, the effects of some organic compounds with different groups such as amide, ether, phenyldiamine, anime and aminophenol on the corrosion behavior of mild steel in acidic media have been investigated. The experimental data were obtained by gravimetric measurements. The results show that these compounds reveal a promising corrosion inhibition where phenyldiamine is the most efficient. The effect of molecular structure on the corrosion inhibition efficiency was investigated by semi-empirical quantum chemical calculations. The electronic properties such as highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO) energy levels, and LUMO-HOMO energy gap orbital density were calculated. The relations between the inhibition efficiency and some quantum parameters are discussed and correlations are proposed. The highest values for the HOMO densities were found in the vicinity nitrogen atom, indicating that it is the most probable adsorption center

  15. Nucleus-encoded mRNAs for chloroplast proteins GapA, PetA, and PsbO are trans-spliced in the flagellate Euglena gracilis irrespective of light and plastid function.

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    Mateášiková-Kováčová, Bianka; Vesteg, Matej; Drahovská, Hana; Záhonová, Kristína; Vacula, Rostislav; Krajčovič, Juraj

    2012-01-01

    Euglena gracilis is a fresh-water flagellate possessing secondary chloroplasts of green algal origin. In contrast with organisms possessing primary plastids, mRNA levels of nucleus-encoded genes for chloroplast proteins in E. gracilis depend on neither light nor plastid function. However, it remains unknown, if all these mRNAs are trans-spliced and possess spliced leader sequence at the 5'-end and if trans-splicing depends on light or functional plastids. This study revealed that polyadenylated mRNAs encoding the chloroplast proteins glyceraldehyde-3-phosphate dehydrogenase (GapA), cytochrome f (PetA), and subunit O of photosystem II (PsbO) are trans-spliced irrespective of light or plastid function. © 2012 The Author(s) Journal of Eukaryotic Microbiology © 2012 International Society of Protistologists.

  16. Efficient inhibition of fibroblast proliferation and collagen expression by ERK2 siRNAs

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    Li, Fengfeng; Fan, Cunyi; Cheng, Tao; Jiang, Chaoyin; Zeng, Bingfang

    2009-01-01

    Transforming growth factor-β1 and fibroblast growth factor-2 play very important roles in fibroblast proliferation and collagen expression. These processes lead to the formation of joint adhesions through the SMAD and MAPK pathways, in which ERK2 is supposed to be crucial. Based on these assumptions, lentivirus (LV)-mediated small interfering RNAs (siRNAs) targeting ERK2 were used to suppress the proliferation and collagen expression of rat joint adhesion tissue fibroblasts (RJATFs). Among four siRNAs examined, siRNA1 caused an 84% reduction in ERK2 expression (p < 0.01) and was selected as the most efficient siRNA for use in this study. In subsequent experiments, significant downregulation of types I and III collagen were observed by quantitative RT-PCR and Western blot analyses. MTT assays and flow cytometry revealed marked inhibition of RJATF proliferation, but no apoptosis. In conclusion, LV-mediated ERK2 siRNAs may represent novel therapies or drug targets for preventing joint adhesion formation.

  17. Efficient inhibition of fibroblast proliferation and collagen expression by ERK2 siRNAs

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    Li, Fengfeng, E-mail: fengmale@yahoo.com.cn [Department of Orthopaedics, The Sixth Affiliated People' s Hospital, Shanghai Jiaotong University School of Medicine, 600 Yishan Road, Shanghai 200233 (China); Fan, Cunyi, E-mail: fancunyi@smmail.cn [Department of Orthopaedics, The Sixth Affiliated People' s Hospital, Shanghai Jiaotong University School of Medicine, 600 Yishan Road, Shanghai 200233 (China); Cheng, Tao, E-mail: goal981003@yahoo.com.cn [Department of Orthopaedics, The Sixth Affiliated People' s Hospital, Shanghai Jiaotong University School of Medicine, 600 Yishan Road, Shanghai 200233 (China); Jiang, Chaoyin, E-mail: limale@163.com [Department of Orthopaedics, The Sixth Affiliated People' s Hospital, Shanghai Jiaotong University School of Medicine, 600 Yishan Road, Shanghai 200233 (China); Zeng, Bingfang, E-mail: zengbingfang@yahoo.com.cn [Department of Orthopaedics, The Sixth Affiliated People' s Hospital, Shanghai Jiaotong University School of Medicine, 600 Yishan Road, Shanghai 200233 (China)

    2009-05-01

    Transforming growth factor-{beta}1 and fibroblast growth factor-2 play very important roles in fibroblast proliferation and collagen expression. These processes lead to the formation of joint adhesions through the SMAD and MAPK pathways, in which ERK2 is supposed to be crucial. Based on these assumptions, lentivirus (LV)-mediated small interfering RNAs (siRNAs) targeting ERK2 were used to suppress the proliferation and collagen expression of rat joint adhesion tissue fibroblasts (RJATFs). Among four siRNAs examined, siRNA1 caused an 84% reduction in ERK2 expression (p < 0.01) and was selected as the most efficient siRNA for use in this study. In subsequent experiments, significant downregulation of types I and III collagen were observed by quantitative RT-PCR and Western blot analyses. MTT assays and flow cytometry revealed marked inhibition of RJATF proliferation, but no apoptosis. In conclusion, LV-mediated ERK2 siRNAs may represent novel therapies or drug targets for preventing joint adhesion formation.

  18. Influence of Macrocyclic Ring Size on the Corrosion Inhibition Efficiency of Dibenzo Crown Ether: A Density Functional Study

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    Saprizal Hadisaputra

    2017-11-01

    Full Text Available The effect of macrocycle ring size on the corrosion inhibition efficiency of dibenzo-12-crown-4 (DB12C4, dibenzo-15-crown-5 (DB15C5, dibenzo-18-crown-6 (DB18C6, dibenzo-21-crown-7 (DB21C7 and dibenzo-24-crown-8 (DB24C8 have been elucidated by mean of density functional calculation at B3LYP/6-31G(d level of theory in the gas and aqueous environment. The quantum chemical parameters including the frontier orbital energies (EHOMO, ELUMO, ionization potential (I, electron affinity (A, the absolute electronegativity (χ, hardness (η, softness (σ, and the fraction of electron transferred (ΔN are positively correlated to the corrosion inhibition efficiency (IE% of the studied crown ethers. The calculation results indicate that DB24C8 exhibits the highest corrosion inhibition efficiency, whereas DB12C4 exhibits the lowest corrosion inhibition efficiency. The results of this study will contribute to design crown ethers potential as corrosion inhibitors.

  19. Inhibition Efficiency in Highly Proficient Bilinguals and Simultaneous Interpreters: Evidence from Language Switching and Stroop Tasks.

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    Aparicio, Xavier; Heidlmayr, Karin; Isel, Frédéric

    2017-12-01

    The present behavioral study aimed to examine the impact of language control expertise on two domain-general control processes, i.e. active inhibition of competing representations and overcoming of inhibition. We compared how Simultaneous Interpreters (SI) and Highly Proficient Bilinguals-two groups assumed to differ in language control capacity-performed executive tasks involving specific inhibition processes. In Experiment 1 (language decision task), both active and overcoming of inhibition processes are involved, while in Experiment 2 (bilingual Stroop task) only interference suppression is supposed to be required. The results of Experiment 1 showed a language switching effect only for the highly proficient bilinguals, potentially because overcoming of inhibition requires more cognitive resources than in SI. Nevertheless, both groups performed similarly on the Stroop task in Experiment 2, which suggests that active inhibition may work similarly in both groups. These contrasting results suggest that overcoming of inhibition may be harder to master than active inhibition. Taken together, these data indicate that some executive control processes may be less sensitive to the degree of expertise in bilingual language control than others. Our findings lend support to psycholinguistic models of bilingualism postulating a higher-order mechanism regulating language activation.

  20. Theoretical study of inhibition efficiencies of some amino acids on corrosion of carbon steel in acidic media: green corrosion inhibitors.

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    Dehdab, Maryam; Shahraki, Mehdi; Habibi-Khorassani, Sayyed Mostafa

    2016-01-01

    Inhibition efficiencies of three amino acids [tryptophan (B), tyrosine (c), and serine (A)] have been studied as green corrosion inhibitors on corrosion of carbon steel using density functional theory (DFT) method in gas and aqueous phases. Quantum chemical parameters such as EH OMO (highest occupied molecular orbital energy), E LUMO (lowest unoccupied molecular orbital energy), hardness (η), polarizability ([Formula: see text]), total negative charges on atoms (TNC), molecular volume (MV) and total energy (TE) have been calculated at the B3LYP level of theory with 6-311++G** basis set. Consistent with experimental data, theoretical results showed that the order of inhibition efficiency is tryptophan (B) > tyrosine (C) > serine (A). In order to determine the possible sites of nucleophilic and electrophilic attacks, local reactivity has been evaluated through Fukui indices.

  1. An efficient process for wastewater treatment to mitigate free nitrous acid generation and its inhibition on biological phosphorus removal

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    Zhao, Jianwei; Wang, Dongbo; Li, Xiaoming; Yang, Qi; Chen, Hongbo; Zhong, Yu; An, Hongxue; Zeng, Guangming

    2015-02-01

    Free nitrous acid (FNA), which is the protonated form of nitrite and inevitably produced during biological nitrogen removal, has been demonstrated to strongly inhibit the activity of polyphosphate accumulating organisms (PAOs). Herein we reported an efficient process for wastewater treatment, i.e., the oxic/anoxic/oxic/extended-idle process to mitigate the generation of FNA and its inhibition on PAOs. The results showed that this new process enriched more PAOs which thereby achieved higher phosphorus removal efficiency than the conventional four-step (i.e., anaerobic/oxic/anoxic/oxic) biological nutrient removal process (41 +/- 7% versus 30 +/- 5% in abundance of PAOs and 97 +/- 0.73% versus 82 +/- 1.2% in efficiency of phosphorus removal). It was found that this new process increased pH value but decreased nitrite accumulation, resulting in the decreased FNA generation. Further experiments showed that the new process could alleviate the inhibition of FNA on the metabolisms of PAOs even under the same FNA concentration.

  2. Structure effect of some amine derivatives on corrosion inhibition efficiency for carbon steel in acidic media using electrochemical and Quantum Theory Methods

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    Ahmed M. Al-Sabagh

    2013-06-01

    Full Text Available The structure effect on corrosion inhibition of two amines and their derivatives is the main object of this article. The first amine was 1,8-diaminooctane and its ethoxylated (50 e.o. 1,8-diaminooctane and propoxylated (50 p.o. 1,8-diaminooctane. The second amine is the tetraethylenepentamine and its ethoxylated (50 e.o. and propoxylated (50 p.o. derivatives. The investigations were carried out by open circuit potential, potentiodynamic polarization, electrochemical impedance, quantum calculations and SEM measurements. The data obtained for the first amine showed the minimum inhibition efficiency (65.5%, meanwhile the maximum inhibition efficiency was 78.9% for its propoxylated derivative. On the other hand the maximium inhibition efficiency was 91% for the second propoxylated amine. The electronic properties; HOMO and LUMO energy levels, energy gap, dipole moment, polarizability, log P, total energy, charge densities, area/molecule and hydration energy have been calculated. The inhibition efficiency was calculated theoretically using the electronic parameters. From the obtained results, there is a significant difference between the inhibition efficiency of the electronic and the inhibition efficiency experimentally. The results were discussed on the light of the chemical structure of the used inhibitors. In general, the inhibition efficiency is affected by the shape and structure of the molecule.

  3. Corrosion inhibition efficiency of linear alkyl benzene derivatives for carbon steel pipelines in 1M HCl

    Directory of Open Access Journals (Sweden)

    A.M. Al-Sabagh

    2011-06-01

    Full Text Available Linear alkyl benzene sulfonic acid (L and three of its ester derivatives (L1, L2, L3 were prepared, followed by quaternization of these esters (L1Q, L2Q, L3Q. The corrosion inhibition effect on carbon steel in 1 M HCl was studied using weight loss and potentiodynamic polarization measurements. The adsorption of the inhibitors on carbon steel surface obeyed the Langmuir’s adsorption isotherm. The associated activation energy of corrosion and other thermodynamic parameters such as enthalpy (ΔH∗, entropy (ΔS∗ of activation, adsorption–desorption equilibrium constant (Kads, standard free energy of adsorption (ΔGoads, heat (ΔHoads, and entropy of adsorption (ΔSoads were calculated to elaborate the corrosion inhibition mechanism.

  4. Conjugates of salicylaldoximes and peripheral site ligands: Novel efficient nonquaternary reactivators for nerve agent-inhibited acetylcholinesterase.

    Science.gov (United States)

    Wei, Zhao; Liu, Yan-Qin; Wang, Sheng-Zheng; Yao, Lin; Nie, Hui-Fang; Wang, Yong-An; Liu, Xue-Ying; Zheng, Zhi-Bing; Li, Song

    2017-08-15

    A new family of nonquaternary reactivators for nerve agent-inhibited human acetylcholinesterase (hAChE) were designed, synthesized and tested in this paper. It was found that salicylaldoximes were able to quickly cleave the P-S bond of organophosphate and avoid the reinhibition phenomenon in the reactivation process, but they lacked reactivating ability due to poor affinity for AChE. Based on a dual site binding strategy, different peripheral site ligands of AChE were introduced to achieve extra affinity. The in vitro reactivation experiments demonstrated that some of the yielding conjugates exhibited similar or even superior ability to reactivate sarin-, VX- or tabun-inhibited hAChE in comparison with the mono- and bis-pyridinium aldoximes currently used. Moreover, due to greatly improved lipophilicity, these nonquaternary conjugates hold promise for the development of efficient centrally activating reactivators. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Phonon scattering inhibits simultaneous near-unity efficiency and indistinguishability in semiconductor single-photon sources

    DEFF Research Database (Denmark)

    Iles-Smith, Jake; McCutcheon, Dara P. S.; Nazir, Ahsan

    2017-01-01

    Semiconductor quantum dots (QDs) have recently emerged as a leading platform to generate highly indistinguishable photons efficiently, and this work addresses the timely question of how good these solid-state sources can ultimately be. We establish the crucial role of lattice relaxation in these ......Semiconductor quantum dots (QDs) have recently emerged as a leading platform to generate highly indistinguishable photons efficiently, and this work addresses the timely question of how good these solid-state sources can ultimately be. We establish the crucial role of lattice relaxation...... relationship, in which indistinguishability and efficiency cannot be simultaneously increased. For cavities, the frequency selectivity of the Purcell enhancement results in a more subtle trade-off, in which indistinguishability and efficiency can be increased simultaneously, although not arbitrarily, which...

  6. Efficient electroreduction of CO{sub 2} on bulk silver electrode in aqueous solution via the inhibition of hydrogen evolution

    Energy Technology Data Exchange (ETDEWEB)

    Quan, Fengjiao; Xiong, Mubing; Jia, Falong, E-mail: fljia@mail.ccnu.edu.cn; Zhang, Lizhi

    2017-03-31

    Highlights: • High Faradic efficiency for CO (95%) is achieved on bulk Ag electrode. • The addition of DTAB contributes to enhanced CO{sub 2} conversion efficiency. • Hydrogen evolution is suppressed by the adsorbed DTAB on Ag electrode. - Abstract: Electrochemical CO{sub 2} reduction provides a desirable pathway to convert greenhouse gas into useful chemicals. It is a great challenge to reduce CO{sub 2} efficiently in aqueous solution, especially on commercial bulk metal electrodes. Here, we report substantial improvement in CO{sub 2} reduction on bulk silver electrode through the introduction of ionic surfactant in aqueous electrolyte. The hydrogen evolution on the electrode surface is greatly suppressed by the surfactant, while the catalytic ability of silver towards CO{sub 2} reduction is maintained. The Faradaic efficiency for CO is greatly enhanced from 50% to 95% after the addition of this low-cost surfactant. This study may provide new pathways towards efficient CO{sub 2} reduction through the inhibition of proton reduction.

  7. Corrosion inhibition efficiency of water soluble ethoxylated trimethylol propane by gravimetric analysis

    Directory of Open Access Journals (Sweden)

    A.A. Abdel-Azim

    2014-03-01

    Full Text Available Polyoxyethylenated trimethylol propane monolaurate surfactants with varied ethylene oxide content were tested as corrosion inhibitors via the weight loss method. Weight loss measurements for carbon steel dissolution were performed in 1 N HCl containing different inhibitor concentrations at 30, 40 and 50 °C. These measurements were utilized for calculating corrosion rate, surface coverage area and percentage inhibition. The obtained data show that the adsorption of these inhibitors obeys Langmuir adsorption isotherm. Thermodynamic parameters (ΔG∗, ΔH∗ and ΔS∗ of the corrosion process are evaluated and correlated to inhibitors structures.

  8. Efficient inhibition of ovarian cancer by degradable nanoparticle-delivered survivin T34A gene

    Science.gov (United States)

    Luo, Li; Du, Ting; Zhang, Jiumeng; Zhao, Wei; Cheng, Hao; Yang, Yuping; Wu, Yujiao; Wang, Chunmei; Men, Ke; Gou, Maling

    2016-01-01

    Gene therapy has promising applications in ovarian cancer therapy. Blocking the function of the survivin protein could lead to the growth inhibition of cancer cells. Herein, we used degradable heparin–polyethyleneimine (HPEI) nanoparticles to deliver a dominant-negative human survivin T34A (hs-T34A) gene to treat ovarian cancer. HPEI nanoparticles were characterized and were found to have a dynamic diameter of 66±4.5 nm and a zeta potential of 27.1±1.87 mV. The constructed hs-T34A gene expression plasmid could be effectively delivered into SKOV3 ovarian carcinoma cells by HPEI nanoparticles with low cytotoxicity. Intraperitoneal administration of HPEI/hs-T34A complexes could markedly inhibit tumor growth in a mouse xenograft model of SKOV3 human ovarian cancer. Moreover, according to our results, apparent apoptosis of cancer cells was observed both in vitro and in vivo. Taken together, the prepared HPEI/hs-T34A formulation showed potential applications in ovarian cancer gene therapy. PMID:26893558

  9. Efficient dynamic molecular simulation using QSAR model to know inhibition activity in breast cancer medicine

    Science.gov (United States)

    Zharifah, A.; Kusumowardani, E.; Saputro, A.; Sarwinda, D.

    2017-07-01

    According to data from GLOBOCAN (IARC) at 2012, breast cancer was the highest rated of new cancer case by 43.3 % (after controlled by age), with mortality rated as high as 12.9 %. Oncology is a major field which focusing on improving the development of drug and therapeutics cancer in pharmaceutical and biotechnology companies. Nowadays, many researchers lead to computational chemistry and bioinformatic for pharmacophore generation. A pharmacophore describes as a group of atoms in the molecule which is considered to be responsible for a pharmacological action. Prediction of biological function from chemical structure in silico modeling reduces the use of chemical reagents so the risk of environmental pollution decreased. In this research, we proposed QSAR model to analyze the composition of cancer drugs which assumed to be homogenous in character and treatment. Atomic interactions which analyzed are learned through parameters such as log p as descriptors hydrophobic, n_poinas descriptor contour strength and molecular structure, and also various concentrations inhibitor (micromolar and nanomolar) from NCBI drugs bank. The differences inhibitor activity was observed by the presence of IC 50 residues value from inhibitor substances at various concentration. Then, we got a general overview of the state of safety for drug stability seen from its IC 50 value. In our study, we also compared between micromolar and nanomolar inhibitor effect from QSAR model results. The QSAR model analysis shows that the drug concentration with nanomolar is better than micromolar, related with the content of inhibitor substances concentration. This QSAR model got the equation: Log 1/IC50 = (0.284) (±0.195) logP + (0.02) (±0.012) n_poin + (-0.005) (±0.083) Inhibition10.2nanoM + (0.1) (±0.079) Inhibition30.5nanoM + (-0.016) (±0.045) Inhibition91.5nanoM + (-2.572) (±1.570) (n = 13; r = 0.813; r2 = 0.660; s = 0.764; F = 2.720; q2 = 0.660).

  10. Synthesis of non-ionic surfactants based on alkylene diamine and evaluation of their corrosion inhibition efficiency on carbon steel in formation water

    Directory of Open Access Journals (Sweden)

    A.M. Al-Sabagh

    2017-03-01

    Full Text Available The inhibitive effects of newly synthesized non-ionic surfactant based on alkylene diamine surfactants on X-65 carbon steel in formation water was investigated by means of electrochemical techniques and quantum chemical study. These derivatives were characterized by FT-IR, and the surface tension and thermodynamic parameters were calculated. The polarization showed that the inhibition efficiency of the prepared compounds was increased with increasing the length of the internal alkyl chain between the two terminal amino groups of diamine. The electronic properties obtained using quantum chemical approach were correlated with the experimental inhibition efficiencies. The surface morphology of carbon steel was investigated using SEM.

  11. Inhibition of PARP1 activity enhances chemotherapeutic efficiency in cisplatin-resistant gastric cancer cells.

    Science.gov (United States)

    Wang, Qiang; Xiong, Jianping; Qiu, Danping; Zhao, Xue; Yan, Donglin; Xu, Wenxia; Wang, Zhangding; Chen, Qi; Panday, Sapna; Li, Aiping; Wang, Shouyu; Zhou, Jianwei

    2017-11-01

    Cisplatin (DDP) is the first line chemotherapeutic drug for several cancers, including gastric cancer (GC). Unfortunately, the rapid development of drug resistance remains a significant challenge for the clinical application of cisplatin. There is an urgent need to develop new strategies to overcome DDP resistance for cancer treatment. In this study, four types of human GC cells have been divided into naturally sensitive or naturally resistant categories according to their responses to cisplatin. PARP1 activity (poly (ADP-ribose), PAR) was found to be greatly increased in cisplatin-resistant GC cells. PARP1 inhibitors significantly enhanced cisplatin-induced DNA damage and apoptosis in the resistant GC cells via the inhibition of PAR. Mechanistically, PARP1 inhibitors suppress DNA-PKcs stability and reduce the capability of DNA double-strand break (DSB) repair via the NHEJ pathway. This was also verified in BGC823/DDP GC cells with acquired cisplatin resistance. In conclusion, we identified that PARP1 is a useful interceptive target in cisplatin-resistant GC cells. Our data provide a promising therapeutic strategy against cisplatin resistance in GC cells that has potential translational significance. Copyright © 2017. Published by Elsevier Ltd.

  12. Requirements for efficient cell-type proportioning: regulatory timescales, stochasticity and lateral inhibition

    Science.gov (United States)

    Pfeuty, B.; Kaneko, K.

    2016-04-01

    The proper functioning of multicellular organisms requires the robust establishment of precise proportions between distinct cell types. This developmental differentiation process typically involves intracellular regulatory and stochastic mechanisms to generate cell-fate diversity as well as intercellular signaling mechanisms to coordinate cell-fate decisions at tissue level. We thus surmise that key insights about the developmental regulation of cell-type proportion can be captured by the modeling study of clustering dynamics in population of inhibitory-coupled noisy bistable systems. This general class of dynamical system is shown to exhibit a very stable two-cluster state, but also metastability, collective oscillations or noise-induced state hopping, which can prevent from timely and reliably reaching a robust and well-proportioned clustered state. To circumvent these obstacles or to avoid fine-tuning, we highlight a general strategy based on dual-time positive feedback loops, such as mediated through transcriptional versus epigenetic mechanisms, which improves proportion regulation by coordinating early and flexible lineage priming with late and firm commitment. This result sheds new light on the respective and cooperative roles of multiple regulatory feedback, stochasticity and lateral inhibition in developmental dynamics.

  13. Exploring the mechanism of high degree of delignification inhibits cellulose conversion efficiency.

    Science.gov (United States)

    Ding, Dayong; Zhou, Xia; You, Tingting; Zhang, Xun; Zhang, Xueming; Xu, Feng

    2018-02-01

    This study explored the mechanism that high degree of delignification (DD) inhibits enzymatic hydrolysis. Sample with DD of 86.22% achieved the highest cellulose conversion of 68.26%, and the cell wall exhibited defibrillation of macrofibrils and erosion of microfibrils during enzymatic hydrolysis. Cracks between microfibrils are formed within the cell wall, getting the largest specific surface area, which greatly enhanced cellulose conversion. However, high DD of 96.58% resulted in dramatic reduction of cellulose conversion to 56.60% which was evidenced to be the synergistic effect of internal cell wall collapse and microfibrils reaggregation. These ultrastructural changes dominated upon this condition and induced a more compact surface structure which significantly hinders the accessibility of cellulase. The CrI value increased after delignification but changed little with the increased DD, suggesting limited influence of DD on crystalline structure. The results indicate that certain amount of lignin retained may be essential to enhance cellulose conversion. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Specific Delivery of MiRNA for High Efficient Inhibition of Prostate Cancer by RNA Nanotechnology.

    Science.gov (United States)

    Binzel, Daniel W; Shu, Yi; Li, Hui; Sun, Meiyan; Zhang, Qunshu; Shu, Dan; Guo, Bin; Guo, Peixuan

    2016-08-01

    Both siRNA and miRNA can serve as powerful gene-silencing reagents but their specific delivery to cancer cells in vivo without collateral damage to healthy cells remains challenging. We report here the application of RNA nanotechnology for specific and efficient delivery of anti-miRNA seed-targeting sequence to block the growth of prostate cancer in mouse models. Utilizing the thermodynamically ultra-stable three-way junction of the pRNA of phi29 DNA packaging motor, RNA nanoparticles were constructed by bottom-up self-assembly containing the anti-prostate-specific membrane antigen (PSMA) RNA aptamer as a targeting ligand and anti-miR17 or anti-miR21 as therapeutic modules. The 16 nm RNase-resistant and thermodynamically stable RNA nanoparticles remained intact after systemic injection in mice and strongly bound to tumors with little or no accumulation in healthy organs 8 hours postinjection, and subsequently repressed tumor growth at low doses with high efficiency.

  15. Prophylactic Dendritic Cell-Based Vaccines Efficiently Inhibit Metastases in Murine Metastatic Melanoma.

    Directory of Open Access Journals (Sweden)

    Oleg V Markov

    Full Text Available Recent data on the application of dendritic cells (DCs as anti-tumor vaccines has shown their great potential in therapy and prophylaxis of cancer. Here we report on a comparison of two treatment schemes with DCs that display the models of prophylactic and therapeutic vaccination using three different experimental tumor models: namely, Krebs-2 adenocarcinoma (primary tumor, melanoma (B16, metastatic tumor without a primary node and Lewis lung carcinoma (LLC, metastatic tumor with a primary node. Dendritic cells generated from bone marrow-derived DC precursors and loaded with lysate of tumor cells or transfected with the complexes of total tumor RNA with cationic liposomes were used for vaccination. Lipofectamine 2000 and liposomes consisting of helper lipid DOPE (1,2-dioleoyl-sn-glycero-3-phosphoethanolamine and cationic lipid 2D3 (1,26-Bis(1,2-de-O-tetradecyl-rac-glycerol-7,11,16,20-tetraazahexacosan tetrahydrocloride were used for RNA transfection. It was shown that DCs loaded with tumor lysate were ineffective in contrast to tumor-derived RNA. Therapeutic vaccination with DCs loaded by lipoplexes RNA/Lipofectamine 2000 was the most efficient for treatment of non-metastatic Krebs-2, where a 1.9-fold tumor growth retardation was observed. Single prophylactic vaccination with DCs loaded by lipoplexes RNA/2D3 was the most efficient to treat highly aggressive metastatic tumors LLC and B16, where 4.7- and 10-fold suppression of the number of lung metastases was observed, respectively. Antimetastatic effect of single prophylactic DC vaccination in metastatic melanoma model was accompanied by the reductions in the levels of Th2-specific cytokines however the change of the levels of Th1/Th2/Th17 master regulators was not found. Failure of double prophylactic vaccination is explained by Th17-response polarization associated with autoimmune and pro-inflammatory reactions. In the case of therapeutic DC vaccine the polarization of Th1-response was found

  16. Novel cationic surfactants from fatty acids and their corrosion inhibition efficiency for carbon steel pipelines in 1 M HCl

    Directory of Open Access Journals (Sweden)

    A.M. Al-Sabagh

    2011-06-01

    Full Text Available Four fatty acids were used as a source of alkyl halides. Untraditionally tertiary amines were prepared by ethoxylation of aromatic and aliphatic fatty amines. These alkyl halide and tertiary amines were used to prepare 20 cationic quaternary ammonium surfactants (QASS. Their chemical structures were characterized and they tested as corrosion inhibitors for carbon steel in 1 M HCl solution. The corrosion inhibition efficiency was measured using, weight loss and potentiodynamic polarization methods. The inhibition efficiencies obtained from the two employed methods are nearly closed. From the obtained data it was found that, the inhibition efficiency increases with increasing the inhibitor concentration until the optimum one. Also, it was found that the inhibition efficiency of QASs which based on ethoxylated aromatic tertiary amine is greater than the obtained efficiencies by the QASs which based on ethoxylated aliphatic tertiary amines. The QASs based on alkyl halide C16 exhibited the maximum inhibition efficiency 98.8%. Adsorption of the inhibitors on the carbon steel surface was found to obey Langmuir’s adsorption isotherm. The quantum chemical calculations were done for some selected quaternary ammonium compounds based on their chemical structures QL1,4,5–QP3,4,5. The following quantum chemical indices such as the bond length, bond angle, charge density distribution, highest occupied molecular orbital (HOMO, lowest unoccupied molecular orbital (LUMO, energy gap ΔE = HOMO − LUMO, and dipole moment (u were considered. The relation between these parameters and the inhibition efficiencies was explained on the light of the chemical structure of the used inhibitors.

  17. Application of calculated NMR parameters, aromaticity indices and wavefunction properties for evaluation of corrosion inhibition efficiency of pyrazine inhibitors

    Science.gov (United States)

    Behzadi, Hadi; Manzetti, Sergio; Dargahi, Maryam; Roonasi, Payman; Khalilnia, Zahra

    2018-01-01

    In light of the importance of developing novel corrosion inhibitors, a series of quantum chemical calculations were carried out to evaluate 15N chemical shielding CS tensors as well as aromaticity indexes including NICS, HOMA, FLU, and PDI of three pyrazine derivatives, 2-methylpyrazine (MP), 2-aminopyrazine (AP) and 2-amino-5-bromopyrazine (ABP). The NICS parameters have been shown in previous studies to be paramount to the prediction of anti-corrosion properties, and have been combined here with HOMA, FLU and PDI and detailed wavefunction analysis to determine the effects from bromination and methylation on pyrazine. The results show that the electron density around the nitrogens, represented by CS tensors, can be good indicators of anti-corrosion efficiency. Additionally, the NICS, FLU and PDI, as aromaticity indicators of molecule, are well correlated with experimental corrosion inhibition efficiencies of the studied inhibitors. Bader sampling and detailed wavefunction analysis shows that the major effects from bromination on the pyrazine derivatives affect the Laplacian of the electron density of the ring, delocalizing the aromatic electrons of the carbon atoms into lone pairs and increasing polarization of the Laplacian values. This feature is well agreement with empirical studies, which show that ABP is the most efficient anti-corrosion compound followed by AP and MP, a property which can be attributed and predicted by derivation of the Laplacian of the electron density of the ring nuclei. This study shows the importance of devising DFT methods for development of new corrosion inhibitors, and the strength of electronic and nuclear analysis, and depicts most importantly how corrosion inhibitors composed of aromatic moieties may be modified to increase anti-corrosive properties.

  18. The Widening Gap--A Swedish Perspective

    Science.gov (United States)

    Brandell, Gerd; Hemmi, Kristi; Thunberg, Hans

    2008-01-01

    Transition problems from secondary to tertiary level in mathematics have been a recurrent issue in Sweden. This paper summarises the development during the last decades. Results from two recent research studies that illuminate the transition problem are presented. The first one, based on empirical data from a major Swedish technical university,…

  19. Effects of Different End-Point Cooking Temperatures on the Efficiency of Encapsulated Phosphates on Lipid Oxidation Inhibition in Ground Meat.

    Science.gov (United States)

    Kılıç, B; Şimşek, A; Claus, J R; Atılgan, E; Aktaş, N

    2015-10-01

    Effects of 0.5% encapsulated (e) phosphates (sodium tripolyphosphate, STP; sodium hexametaphosphate, HMP; sodium pyrophosphate, SPP) on lipid oxidation during storage (0, 1, and 7 d) of ground meat (chicken, beef) after being cooked to 3 end-point cooking temperatures (EPCT; 71, 74, and 77 °C) were evaluated. The use of STP or eSTP resulted in lower (P phosphates can be a strategy to inhibit lipid oxidation for meat industry and the efficiency of encapsulated phosphates on lipid oxidation inhibition can be enhanced by lowering EPCT. © 2015 Institute of Food Technologists®

  20. The effects of action video game experience on the time course of inhibition of return and the efficiency of visual search.

    Science.gov (United States)

    Castel, Alan D; Pratt, Jay; Drummond, Emily

    2005-06-01

    The ability to efficiently search the visual environment is a critical function of the visual system, and recent research has shown that experience playing action video games can influence visual selective attention. The present research examined the similarities and differences between video game players (VGPs) and non-video game players (NVGPs) in terms of the ability to inhibit attention from returning to previously attended locations, and the efficiency of visual search in easy and more demanding search environments. Both groups were equally good at inhibiting the return of attention to previously cued locations, although VGPs displayed overall faster reaction times to detect targets. VGPs also showed overall faster response time for easy and difficult visual search tasks compared to NVGPs, largely attributed to faster stimulus-response mapping. The findings suggest that relative to NVGPs, VGPs rely on similar types of visual processing strategies but possess faster stimulus-response mappings in visual attention tasks.

  1. Synthesis, spectroscopic characterization and a comparative study of the corrosion inhibitive efficiency of an α-aminophosphonate and Schiff base derivatives: Experimental and theoretical investigations

    Science.gov (United States)

    Benbouguerra, Khalissa; Chafaa, Salah; Chafai, Nadjib; Mehri, Mouna; Moumeni, Ouahiba; Hellal, Abdelkader

    2018-04-01

    New α-aminophosphonate (α-APD) and Schiff base (E-NDPIMA) derivatives have been prepared and their structures ware proved by IR, UV-Vis, 1H, 13C and 31P NMR spectroscopy. Their inhibitive capacities on the XC48 carbon steel corrosion in 0.5 mol L-1 H2SO4 solution were explored by weight loss, Tafel polarization, electrochemical impedance spectroscopy (EIS) and atomic force microscope (AFM). Experimental results illustrate that the synthesized compounds are an effectives inhibitors and the adsorption of inhibitors molecules on the carbon steel surface obeys Langmuir adsorption isotherm. In addition, quantum chemical calculations performed with density function theory (DFT) method have been used to correlate the inhibition efficiency established experimentally. Also, the molecular dynamics simulations have been utilized to simulate the interactions between the inhibitors molecules and Fe (100) surface in aqueous solution.

  2. MEK-ERK inhibition potentiates WAY-600-induced anti-cancer efficiency in preclinical hepatocellular carcinoma (HCC) models

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Kaifeng, E-mail: kaifeng_wangdr@sina.com [Cancer center, the Affiliated Hospital of Hangzhou Normal University, Hangzhou (China); Fan, Yaohua [Oncology Department, No. 1 Hospital of Jiaxing, Zhejiang Province, Jiaxing (China); Chen, Gongying [Oncology Department, The Affiliated Hospital Hangzhou Normal University, Hangzhou (China); Wang, Zhengrong [Taizhou Hospital, Zhejiang Province, Taizhou (China); Kong, Dexin; Zhang, Peng [Oncology Department, Sir Run Run Shaw Hospital, Medical School, Zhejiang University, Hangzhou (China)

    2016-05-27

    The search for novel anti-hepatocellular carcinoma (HCC) agents is important. Mammalian target of rapamycin (mTOR) hyper-activation plays a pivotal role in promoting HCC tumorigenesis and chemoresistance. The current preclinical study evaluated the potential anti-HCC activity by a potent mTOR kinase inhibitor, WAY-600. We showed that WAY-600 inhibited survival and proliferation of HCC cell lines (HepG2 and Huh7) and primary human HCC cells. Caspase-dependent apoptosis was activated by WAY-600 in above HCC cells. Reversely, caspase inhibitors largely attenuated WAY-600's lethality against HCC cells. At the signaling level, WAY-600 blocked mTOR complex 1/2 (mTORC1/2) assemble and activation, yet activated MEK-ERK pathway in HCC cells. MEK-ERK inhibitors, PD-98059 and MEK-162, or MEK1/2 shRNA significantly potentiated WAY-600's cytotoxicity in HCC cells. Further studies showed that WAY-600 intraperitoneal (i.p.) administration in nude mice inhibited p-AKT Ser-473 and displayed significant anti-cancer activity against HepG2 xenografts. Remarkably, co-administration of MEK-162 further potentiated WAY-600's anti-HCC activity in vivo. These preclinical results demonstrate the potent anti-HCC activity by WAY-600, either alone or with MEK-ERK inhibitors. -- Highlights: •WAY-600 inhibits HCC cell survival and proliferation in vitro. •WAY-600 activates caspase-dependent apoptosis in HCC cells. •WAY-600 blocks mTORC1/2 activation, but activates MEK-ERK in HCC cells. •MEK-ERK inhibitors or MEK1/2 shRNA enhances WAY-600's cytotoxicity against HCC cells. •MEK-162 co-administration potentiates WAY-600-induced the anti-HepG2 tumor efficacy.

  3. MEK-ERK inhibition potentiates WAY-600-induced anti-cancer efficiency in preclinical hepatocellular carcinoma (HCC) models

    International Nuclear Information System (INIS)

    Wang, Kaifeng; Fan, Yaohua; Chen, Gongying; Wang, Zhengrong; Kong, Dexin; Zhang, Peng

    2016-01-01

    The search for novel anti-hepatocellular carcinoma (HCC) agents is important. Mammalian target of rapamycin (mTOR) hyper-activation plays a pivotal role in promoting HCC tumorigenesis and chemoresistance. The current preclinical study evaluated the potential anti-HCC activity by a potent mTOR kinase inhibitor, WAY-600. We showed that WAY-600 inhibited survival and proliferation of HCC cell lines (HepG2 and Huh7) and primary human HCC cells. Caspase-dependent apoptosis was activated by WAY-600 in above HCC cells. Reversely, caspase inhibitors largely attenuated WAY-600's lethality against HCC cells. At the signaling level, WAY-600 blocked mTOR complex 1/2 (mTORC1/2) assemble and activation, yet activated MEK-ERK pathway in HCC cells. MEK-ERK inhibitors, PD-98059 and MEK-162, or MEK1/2 shRNA significantly potentiated WAY-600's cytotoxicity in HCC cells. Further studies showed that WAY-600 intraperitoneal (i.p.) administration in nude mice inhibited p-AKT Ser-473 and displayed significant anti-cancer activity against HepG2 xenografts. Remarkably, co-administration of MEK-162 further potentiated WAY-600's anti-HCC activity in vivo. These preclinical results demonstrate the potent anti-HCC activity by WAY-600, either alone or with MEK-ERK inhibitors. -- Highlights: •WAY-600 inhibits HCC cell survival and proliferation in vitro. •WAY-600 activates caspase-dependent apoptosis in HCC cells. •WAY-600 blocks mTORC1/2 activation, but activates MEK-ERK in HCC cells. •MEK-ERK inhibitors or MEK1/2 shRNA enhances WAY-600's cytotoxicity against HCC cells. •MEK-162 co-administration potentiates WAY-600-induced the anti-HepG2 tumor efficacy.

  4. Efficient inhibition of tumor angiogenesis and growth by a synthetic peptide blocking S100A4-methionine aminopeptidase 2 interaction

    Directory of Open Access Journals (Sweden)

    Takahiro Ochiya

    Full Text Available The prometastatic calcium-binding protein, S100A4, is expressed in endothelial cells, and its downregulation markedly suppresses tumor angiogenesis in a xenograft cancer model. Given that endothelial S100A4 can be a molecular target for inhibiting tumor angiogenesis, we addressed here whether synthetic peptide capable of blocking S100A4-effector protein interaction could be a novel antiangiogenic agent. To examine this hypothesis, we focused on the S100A4-binding domain of methionine aminopeptidase 2, an effector protein, which plays a role in endothelial cell growth. Overexpression of the domain in mouse endothelial MSS31 cells reduced DNA synthesis, and the corresponding synthetic peptide (named NBD indeed interacted with S100A4 and inhibited capillary formation in vitro and new blood vessel formation in vivo. Intriguingly, a single intra-tumor administration of the NBD peptide in human prostate cancer xenografts significantly reduced vascularity, resulting in tumor regression. Mechanistically, the NBD peptide enhanced assembly of nonmuscle myosin IIA filaments along with Ser1943 phosphorylation, stimulated formation of focal adhesions without phosphorylation of focal adhesion kinase, and provoked G1/S arrest of the cell cycle. Altogether, the NBD peptide is a potent inhibitor for tumor angiogenesis, and is the first example of an anticancer peptide drug developed on the basis of an endothelial S100A4-targeted strategy.

  5. Long-term, efficient inhibition of microRNA function in mice using rAAV vectors.

    Science.gov (United States)

    Xie, Jun; Ameres, Stefan L; Friedline, Randall; Hung, Jui-Hung; Zhang, Yu; Xie, Qing; Zhong, Li; Su, Qin; He, Ran; Li, Mengxin; Li, Huapeng; Mu, Xin; Zhang, Hongwei; Broderick, Jennifer A; Kim, Jason K; Weng, Zhiping; Flotte, Terence R; Zamore, Phillip D; Gao, Guangping

    2012-03-04

    Understanding the function of individual microRNA (miRNA) species in mice would require the production of hundreds of loss-of-function strains. To accelerate analysis of miRNA biology in mammals, we combined recombinant adeno-associated virus (rAAV) vectors with miRNA 'tough decoys' (TuDs) to inhibit specific miRNAs. Intravenous injection of rAAV9 expressing anti-miR-122 or anti-let-7 TuDs depleted the corresponding miRNA and increased its mRNA targets. rAAV producing anti-miR-122 TuD but not anti-let-7 TuD reduced serum cholesterol by >30% for 25 weeks in wild-type mice. High-throughput sequencing of liver miRNAs from the treated mice confirmed that the targeted miRNAs were depleted and revealed that TuDs induced miRNA tailing and trimming in vivo. rAAV-mediated miRNA inhibition thus provides a simple way to study miRNA function in adult mammals and a potential therapy for dyslipidemia and other diseases caused by miRNA deregulation.

  6. Efficient inhibition of tumor angiogenesis and growth by a synthetic peptide blocking S100A4-methionine aminopeptidase 2 interaction.

    Science.gov (United States)

    Ochiya, Takahiro; Takenaga, Keizo; Asagiri, Masataka; Nakano, Kazumi; Satoh, Hitoshi; Watanabe, Toshiki; Imajoh-Ohmi, Shinobu; Endo, Hideya

    2015-01-01

    The prometastatic calcium-binding protein, S100A4, is expressed in endothelial cells, and its downregulation markedly suppresses tumor angiogenesis in a xenograft cancer model. Given that endothelial S100A4 can be a molecular target for inhibiting tumor angiogenesis, we addressed here whether synthetic peptide capable of blocking S100A4-effector protein interaction could be a novel antiangiogenic agent. To examine this hypothesis, we focused on the S100A4-binding domain of methionine aminopeptidase 2, an effector protein, which plays a role in endothelial cell growth. Overexpression of the domain in mouse endothelial MSS31 cells reduced DNA synthesis, and the corresponding synthetic peptide (named NBD) indeed interacted with S100A4 and inhibited capillary formation in vitro and new blood vessel formation in vivo. Intriguingly, a single intra-tumor administration of the NBD peptide in human prostate cancer xenografts significantly reduced vascularity, resulting in tumor regression. Mechanistically, the NBD peptide enhanced assembly of nonmuscle myosin IIA filaments along with Ser1943 phosphorylation, stimulated formation of focal adhesions without phosphorylation of focal adhesion kinase, and provoked G1/S arrest of the cell cycle. Altogether, the NBD peptide is a potent inhibitor for tumor angiogenesis, and is the first example of an anticancer peptide drug developed on the basis of an endothelial S100A4-targeted strategy.

  7. MEK-ERK inhibition potentiates WAY-600-induced anti-cancer efficiency in preclinical hepatocellular carcinoma (HCC) models.

    Science.gov (United States)

    Wang, Kaifeng; Fan, Yaohua; Chen, Gongying; Wang, Zhengrong; Kong, Dexin; Zhang, Peng

    2016-05-27

    The search for novel anti-hepatocellular carcinoma (HCC) agents is important. Mammalian target of rapamycin (mTOR) hyper-activation plays a pivotal role in promoting HCC tumorigenesis and chemoresistance. The current preclinical study evaluated the potential anti-HCC activity by a potent mTOR kinase inhibitor, WAY-600. We showed that WAY-600 inhibited survival and proliferation of HCC cell lines (HepG2 and Huh7) and primary human HCC cells. Caspase-dependent apoptosis was activated by WAY-600 in above HCC cells. Reversely, caspase inhibitors largely attenuated WAY-600's lethality against HCC cells. At the signaling level, WAY-600 blocked mTOR complex 1/2 (mTORC1/2) assemble and activation, yet activated MEK-ERK pathway in HCC cells. MEK-ERK inhibitors, PD-98059 and MEK-162, or MEK1/2 shRNA significantly potentiated WAY-600's cytotoxicity in HCC cells. Further studies showed that WAY-600 intraperitoneal (i.p.) administration in nude mice inhibited p-AKT Ser-473 and displayed significant anti-cancer activity against HepG2 xenografts. Remarkably, co-administration of MEK-162 further potentiated WAY-600's anti-HCC activity in vivo. These preclinical results demonstrate the potent anti-HCC activity by WAY-600, either alone or with MEK-ERK inhibitors. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Efficient inhibition of murine breast cancer growth and metastasis by gene transferred mouse survivin Thr34→Ala mutant

    Directory of Open Access Journals (Sweden)

    Chen li-Juan

    2008-09-01

    Full Text Available Abstract Background Metastasis in breast cancer is a vital concern in treatment because most women with primary breast cancer have micrometastases to distant sites at diagnosis. As a member of the inhibitor of apoptosis protein (IAP family, survivin has been proposed as an attractive target for new anticancer interventions. In this study, we investigated the role of the plasmid encoding the phosphorylation-defective mouse survivin threonine 34→alanine mutant (Msurvivin T34A plasmid in suppressing both murine primary breast carcinomas and pulmonary metastases. Methods In vitro study, induction of apoptosis by Msurvivin T34A plasmid complexed with cationic liposome (DOTAP/Chol was examined by PI staining fluorescence microscopy and flow cytometric analysis. The anti-tumor and anti-metastases activity of Msurvivin T34A plasmid complexed with cationic liposome (DOTAP/Chol was evaluated in female BALB/c mice bearing 4T1 s.c. tumors. Mice were treated twice weekly with i.v. administration of Msurvivin T34A plasmid complexed with cationic liposome (DOTAP/Chol, PORF-9 null plasmid complexed with cationic liposome (DOTAP/Chol, 0.9% NaCl solution for 4 weeks. Tumor volume was observed. After sacrificed, tumor net weight was measured and Lung metastatic nodules of each group were counted. Assessment of apoptotic cells by TUNEL assay was conducted in tumor tissue. Microvessel density within tumor tissue was determined by CD31 immunohistochemistry. Alginate-encapsulated tumor cells test was conducted to evaluate the effect on angiogenesis. By experiment of cytotoxicity T lymphocytes, we test whether Msurvivin T34A plasmid complexed with cationic liposome (DOTAP/Chol can induce specific cell immune response. Results Administration of Msurvivin T34A plasmid complexed with cationic liposome (DOTAP/Chol resulted in significant inhibition in the growth and metastases of 4T1 tumor model. These anti-tumor and anti-metastases responses were associated with

  9. Enhancement of excision-repair efficiency by conditioned medium from density-inhibited cultures in V79 Chinese hamster cells

    International Nuclear Information System (INIS)

    Nakano, S.

    1979-01-01

    Conditioned medium from density-inhibited V79 Chinese hamster cell cultures, given as a post-treatment to UV-irradiated homologous cells, was demonstrated to reduce the lethal action of ultraviolet light by temporarily blocking DNA replication. Since the increased survival was not affected by various nontoxic concentrations of caffeine, such protective effect would be attributable to the prolonged intervention of excision repair before DNA replication during the post-treatment period. The influence of conditioned medium on the UV-induced mutation at the ouabain-resistance locus was also examined and a significant decrease in mutation frequecy was noted. The observed reduction in killing and mutation as a result of post-incubation in conditioned medium, which delays DNA replication, would be interpreted as evidence that conditioned medium provides a longer period of time for an error-free excision-repair process, leaving lesion in DNA available for error-prone post-replication repair. (Auth.)

  10. Efficient visible-light photocatalytic and enhanced photocorrosion inhibition of Ag2WO4 decorated MoS2 nanosheets

    Science.gov (United States)

    Thangavel, Sakthivel; Thangavel, Srinivas; Raghavan, Nivea; Alagu, Raja; Venugopal, Gunasekaran

    2017-11-01

    The use of two-dimensional nanomaterials as co-catalysts in the photodegradation of toxic compounds using light irradiation is an attractive ecofriendly process. In this study, we prepared a novel MoS2/Ag2WO4 nanohybrid via a one-step hydrothermal approach and the photocatalytic properties were investigated by the degradation of methyl-orange under stimulated irradiation. The nanohybrid exhibits enhanced efficiency in dye degradation compared to the bare Ag2WO4 nanorods; the same has been evidently confirmed with UV-visible spectra and total organic carbon removal analysis. The pseudo-first order rate constant of the nanohybrid is nearly 1.8 fold higher than that of the bare Ag2WO4 nanorods. With the aid of classical radical quenching and photoluminescence spectral analysis, a reasonable mechanism has been derived for the addition of MoS2 to nanohybrids to enhance the photocatalytic efficiency. MoS2 prevents photocorrosion of Ag2WO4 and also diminishes the number of photogenerated electron-hole recombination. Our findings could provide new insights in understanding the mechanism of the MoS2/Ag2WO4 nanohybrid as an efficient photocatalyst suitable for waste-water treatment and remedial applications.

  11. A novel mechanism of V-type zinc inhibition of glutamate dehydrogenase results from disruption of subunit interactions necessary for efficient catalysis.

    Science.gov (United States)

    Bailey, Jaclyn; Powell, Lakeila; Sinanan, Leander; Neal, Jacob; Li, Ming; Smith, Thomas; Bell, Ellis

    2011-09-01

    Bovine glutamate dehydrogenase is potently inhibited by zinc and the major impact is on V(max) suggesting a V-type effect on catalysis or product release. Zinc inhibition decreases as glutamate concentrations decrease suggesting a role for subunit interactions. With the monocarboxylic amino acid norvaline, which gives no evidence of subunit interactions, zinc does not inhibit. Zinc significantly decreases the size of the pre-steady state burst in the reaction but does not affect NADPH binding in the enzyme-NADPH-glutamate complex that governs the steady state turnover, again suggesting that zinc disrupts subunit interactions required for catalytic competence. While differential scanning calorimetry suggests zinc binds and induces a slightly conformationally more rigid state of the protein, limited proteolysis indicates that regions in the vicinity of the antennae regions and the trimer-trimer interface become more flexible. The structures of glutamate dehydrogenase bound with zinc and europium show that zinc binds between the three dimers of subunits in the hexamer, a region shown to bind novel inhibitors that block catalytic turnover, which is consistent with the above findings. In contrast, europium binds to the base of the antenna region and appears to abrogate the inhibitory effect of zinc. Structures of various states of the enzyme have shown that both regions are heavily involved in the conformational changes associated with catalytic turnover. These results suggest that the V-type inhibition produced with glutamate as the substrate results from disruption of subunit interactions necessary for efficient catalysis rather than by a direct effect on the active site conformation. © 2011 The Authors Journal compilation © 2011 FEBS.

  12. A Novel Mechanism of V Type Zinc Inhibition of Glutamate Dehydrogenase Results from Disruption of Subunit Interactions Necessary for Efficient Catalysis

    Science.gov (United States)

    Bailey, Jaclyn; Powell, Lakeila; Sinanan, Leander; Neal, Jacob; Li, Ming; Smith, Thomas; Bell, Ellis

    2011-01-01

    SUMMARY Bovine Glutamate Dehydrogenase is potently inhibited by zinc and the major impact is on Vmax suggesting a V-type effect on catalysis or product release. Zinc inhibition decreases as glutamate concentrations decrease suggesting a role for subunit interactions. With the monocarboxylic amino acid, norvaline, which gives no evidence of subunit interactions zinc does not inhibit. Zinc significantly decreases the size of the pre-steady state burst in the reaction but does not affect NADPH binding in the Enzyme-NADPH-glutamate complex that governs the steady state turn-over again suggesting that zinc disrupts subunit interactions required for catalytic competence. While differential scanning calorimetry suggests zinc binds and induces a slightly conformationally more rigid state of the protein, limited proteolysis indicate regions in the vicinity of the antennae regions and the trimer-trimer interface become more flexible. The structures of GDH bound with zinc and europium show that zinc binds between the three dimers of subunits in the hexamer, a region shown to bind novel inhibitors that block catalytic turnover and is consistent with the above findings. In contrast, europium binds to the base of the antenna region and appears to abrogate the inhibitory effect of zinc. Structures of various states of the enzyme have shown that both regions are heavily involved in the conformational changes associated with catalytic turnover. These results suggest that the V-type inhibition produced with glutamate as the substrate results from disruption of subunit interactions necessary for efficient catalysis rather than by a direct effect on the active site conformation. PMID:21749647

  13. Intracytoplasmic stable expression of IgG1 antibody targeting NS3 helicase inhibits replication of highly efficient hepatitis C Virus 2a clone

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    Clementi Massimo

    2010-06-01

    Full Text Available Abstract Background Hepatitis C virus (HCV infection is a major public health problem with more than 170 million cases of chronic infections worldwide. There is no protective vaccine currently available for HCV, therefore the development of novel strategy to prevent chronic infection is important. We reported earlier that a recombinant human antibody clone blocks viral NS3 helicase activity and inhibits replication of HCV 1b virus. This study was performed further to explore the mechanism of action of this recombinant antibody and to determine whether or not this antibody inhibits replication and infectivity of a highly efficient JFH1 HCV 2a virus clone. Results The antiviral effect of intracellular expressed antibody against the HCV 2a virus strain was examined using a full-length green fluorescence protein (GFP labeled infectious cell culture system. For this purpose, a Huh-7.5 cell line stably expressing the NS3 helicase gene specific IgG1 antibody was prepared. Replication of full-length HCV-GFP chimera RNA and negative-strand RNA was strongly inhibited in Huh-7.5 cells stably expressing NS3 antibody but not in the cells expressing an unrelated control antibody. Huh-7.5 cells stably expressing NS3 helicase antibody effectively suppressed infectious virus production after natural infection and the level of HCV in the cell free supernatant remained undetectable after first passage. In contrast, Huh-7.5 cells stably expressing an control antibody against influenza virus had no effect on virus production and high-levels of infectious HCV were detected in culture supernatants over four rounds of infectivity assay. A recombinant adenovirus based expression system was used to demonstrate that Huh-7.5 replicon cell line expressing the intracellular antibody strongly inhibited the replication of HCV-GFP RNA. Conclusion Recombinant human anti-HCV NS3 antibody clone inhibits replication of HCV 2a virus and infectious virus production. Intracellular

  14. Solute carrier protein family 11 member 1 (Slc11a1) activation efficiently inhibits Leishmania donovani survival in host macrophages.

    Science.gov (United States)

    Singh, Nisha; Gedda, Mallikarjuna Rao; Tiwari, Neeraj; Singh, Suya P; Bajpai, Surabhi; Singh, Rakesh K

    2017-09-01

    Visceral leishmaniasis (kala-azar), a life threatening disease caused by L. donovani , is a latent threat to more than 147 million people living in disease endemic South East Asia region of the Indian subcontinent. The therapeutic option to control leishmanial infections are very limited, and at present comprise only two drugs, an antifungal amphotericin B and an antitumor miltefosine, which are also highly vulnerable for parasitic resistance. Therefore, identification and development of alternate control measures is an exigent requirement to control leishmanial infections. In this study, we report that functionally induced expression of solute carrier protein family 11 member 1 ( Slc11a1), a transmembrane divalent cationic transporter recruited on the surface of phagolysosomes after phagocytosis of parasites, effectively inhibits Leishmania donovani growth in host macrophages. Further, the increased Slc11a1 functionality also resulted in increased production of NOx, TNF-α and IL-12 by activated macrophages. The findings of this study signify the importance of interplay between Slc11a1 expression and macrophages activation that can be effectively used to control of Leishmania growth and survival.

  15. Boronic acid-modified lipid nanocapsules: a novel platform for the highly efficient inhibition of hepatitis C viral entry

    Science.gov (United States)

    Khanal, Manakamana; Barras, Alexandre; Vausselin, Thibaut; Fénéant, Lucie; Boukherroub, Rabah; Siriwardena, Aloysius; Dubuisson, Jean; Szunerits, Sabine

    2015-01-01

    The search for viral entry inhibitors that selectively target viral envelope glycoproteins has attracted increasing interest in recent years. Amongst the handful of molecules reported to show activity as hepatitis C virus (HCV) entry inhibitors are a variety of glycan-binding proteins including the lectins, cyanovirin-N (CV-N) and griffithsin. We recently demonstrated that boronic acid-modified nanoparticles are able to reduce HCV entry through a similar mechanism to that of lectins. A major obstacle to any further development of these nanostructures as viral entry inhibitors is their only moderate maximal inhibition potential. In the present study, we report that lipid nanocapsules (LNCs), surface-functionalized with amphiphilic boronic acid (BA) through their post-insertion into the semi-rigid shell of the LNCs, are indeed far superior as HCV entry inhibitors when compared with previously reported nanostructures. These 2nd generation particles (BA-LNCs) are shown to prevent HCV infection in the micromolar range (IC50 = 5.4 μM of BA moieties), whereas the corresponding BA monomers show no significant effects even at the highest analyzed concentration (20 μM). The new BA-LNCs are the most promising boronolectin-based HCV entry inhibitors reported to date and are thus observed to show great promise in the development of a pseudolectin-based therapeutic agent.The search for viral entry inhibitors that selectively target viral envelope glycoproteins has attracted increasing interest in recent years. Amongst the handful of molecules reported to show activity as hepatitis C virus (HCV) entry inhibitors are a variety of glycan-binding proteins including the lectins, cyanovirin-N (CV-N) and griffithsin. We recently demonstrated that boronic acid-modified nanoparticles are able to reduce HCV entry through a similar mechanism to that of lectins. A major obstacle to any further development of these nanostructures as viral entry inhibitors is their only moderate maximal

  16. Improved Ventilatory Efficiency with Locomotor Muscle Afferent Inhibition is Strongly Associated with Leg Composition in Heart Failure.

    Science.gov (United States)

    Keller-Ross, Manda L; Johnson, Bruce D; Carter, Rickey E; Joyner, Michael J; Eisenach, John H; Curry, Timothy B; Olson, Thomas P

    2016-01-01

    Skeletal muscle atrophy contributes to increased afferent feedback (group III and IV) and may influence ventilatory control (high VE/VCO2 slope) in heart failure (HF). This study examined the influence of muscle mass on the change in VE/VCO2 with afferent neural block during exercise in HF. 17 participants [9 HF (60±6 yrs) and 8 controls (CTL) (63±7 yrs, mean±SD)] completed 3 sessions. Session 1: dual energy x-ray absorptiometry and graded cycle exercise to volitional fatigue. Sessions 2 and 3: 5 min of constant-work cycle exercise (65% of peak power) randomized to lumbar intrathecal injection of fentanyl (afferent blockade) or placebo. Ventilation (VE) and gas exchange (oxygen consumption, VO2; carbon dioxide production, VCO2) were measured. Peak work and VO2 were lower in HF (pLeg fat was greater in HF (34.4±3.0 and 26.3±1.8%) and leg muscle mass was lower in HF (63.0±2.8 and 70.4±1.8%, respectively, pleg muscle mass (r2=0.58, pleg fat mass (r2=0.73, pleg muscle mass had the greatest improvement in VE/VCO2 with afferent blockade with leg fat mass being the only predictor for the improvement in VE/VCO2 slope. Both leg muscle mass and fat mass are important contributors to ventilatory abnormalities and strongly associated to improvements in VE/VCO2 slope with locomotor afferent inhibition in HF. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  17. Toll-like receptor-2 agonist-allergen coupling efficiently redirects Th2 cell responses and inhibits allergic airway eosinophilia.

    Science.gov (United States)

    Krishnaswamy, Jayendra Kumar; Jirmo, Adan Chari; Baru, Abdul Mannan; Ebensen, Thomas; Guzmán, Carlos A; Sparwasser, Tim; Behrens, Georg M N

    2012-12-01

    Toll-like receptor (TLR) agonists beneficially modulate allergic airway inflammation. However, the efficiency of TLR agonists varies considerably, and their exact cellular mechanisms (especially of TLR 2/6 agonists) are incompletely understood. We investigated at a cellular level whether the administration of the pharmacologically improved TLR2/6 agonist S-[2,3-bispalmitoyiloxy-(2R)-propyl]-R-cysteinyl-amido-monomethoxy polyethylene glycol (BPP) conjugated to antigenic peptide (BPP-OVA) could divert an existing Th2 response and influence airway eosinophilia. The effects of BPP-OVA on airway inflammation were assessed in a classic murine sensitization/challenge model and an adoptive transfer model, which involved the adoptive transfer of in vitro differentiated ovalbumin (OVA)-specific Th2 cells. Functional T-cell stimulation by lung dendritic cells (DCs) was determined both in vitro and in vivo, combined with a cytokine secretion analysis. A single mucosal application of BPP-OVA efficiently delivered antigen, led to TLR2-mediated DC activation, and resulted in OVA-specific T-cell proliferation via lung DCs in vivo. In alternative models of allergic airway disease, a single administration of BPP-OVA before OVA challenge (but not BPP alone) significantly reduced airway eosinophilia, most likely through altered antigen-specific T-cell stimulation via DCs. Analyses of adoptively transferred Th2-biased cells after BPP-OVA administration in vivo suggested that BPP-OVA guides antigen-specific Th2 cells to produce significantly higher amounts of IFN-γ upon allergen challenge. In conclusion, our data show for the first time that a single mucosal administration of a TLR 2/6 agonist-allergen conjugate can provoke IFN-γ responses in Th2-biased cells and alleviate allergic airway inflammation.

  18. Efficacy of Cognitive Training in Older Adults with and without Subjective Cognitive Decline Is Associated with Inhibition Efficiency and Working Memory Span, Not with Cognitive Reserve

    Science.gov (United States)

    López-Higes, Ramón; Martín-Aragoneses, María T.; Rubio-Valdehita, Susana; Delgado-Losada, María L.; Montejo, Pedro; Montenegro, Mercedes; Prados, José M.; de Frutos-Lucas, Jaisalmer; López-Sanz, David

    2018-01-01

    The present study explores the role of cognitive reserve, executive functions, and working memory (WM) span, as factors that might explain training outcomes in cognitive status. Eighty-one older adults voluntarily participated in the study, classified either as older adults with subjective cognitive decline or cognitively intact. Each participant underwent a neuropsychological assessment that was conducted both at baseline (entailing cognitive reserve, executive functions, WM span and depressive symptomatology measures, as well as the Mini-Mental State Exam regarding initial cognitive status), and then 6 months later, once each participant had completed the training program (Mini-Mental State Exam at the endpoint). With respect to cognitive status the training program was most beneficial for subjective cognitive decline participants with low efficiency in inhibition at baseline (explaining a 33% of Mini-Mental State Exam total variance), whereas for cognitively intact participants training gains were observed for those who presented lower WM span. PMID:29456502

  19. Efficacy of Cognitive Training in Older Adults with and without Subjective Cognitive Decline Is Associated with Inhibition Efficiency and Working Memory Span, Not with Cognitive Reserve.

    Science.gov (United States)

    López-Higes, Ramón; Martín-Aragoneses, María T; Rubio-Valdehita, Susana; Delgado-Losada, María L; Montejo, Pedro; Montenegro, Mercedes; Prados, José M; de Frutos-Lucas, Jaisalmer; López-Sanz, David

    2018-01-01

    The present study explores the role of cognitive reserve, executive functions, and working memory (WM) span, as factors that might explain training outcomes in cognitive status. Eighty-one older adults voluntarily participated in the study, classified either as older adults with subjective cognitive decline or cognitively intact. Each participant underwent a neuropsychological assessment that was conducted both at baseline (entailing cognitive reserve, executive functions, WM span and depressive symptomatology measures, as well as the Mini-Mental State Exam regarding initial cognitive status), and then 6 months later, once each participant had completed the training program (Mini-Mental State Exam at the endpoint). With respect to cognitive status the training program was most beneficial for subjective cognitive decline participants with low efficiency in inhibition at baseline (explaining a 33% of Mini-Mental State Exam total variance), whereas for cognitively intact participants training gains were observed for those who presented lower WM span.

  20. Efficacy of Cognitive Training in Older Adults with and without Subjective Cognitive Decline Is Associated with Inhibition Efficiency and Working Memory Span, Not with Cognitive Reserve

    Directory of Open Access Journals (Sweden)

    Ramón López-Higes

    2018-02-01

    Full Text Available The present study explores the role of cognitive reserve, executive functions, and working memory (WM span, as factors that might explain training outcomes in cognitive status. Eighty-one older adults voluntarily participated in the study, classified either as older adults with subjective cognitive decline or cognitively intact. Each participant underwent a neuropsychological assessment that was conducted both at baseline (entailing cognitive reserve, executive functions, WM span and depressive symptomatology measures, as well as the Mini-Mental State Exam regarding initial cognitive status, and then 6 months later, once each participant had completed the training program (Mini-Mental State Exam at the endpoint. With respect to cognitive status the training program was most beneficial for subjective cognitive decline participants with low efficiency in inhibition at baseline (explaining a 33% of Mini-Mental State Exam total variance, whereas for cognitively intact participants training gains were observed for those who presented lower WM span.

  1. A single bivalent efficiently inhibits cyclin B1 degradation and polar body extrusion in mouse oocytes indicating robust SAC during female meiosis I.

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    Steffen Hoffmann

    Full Text Available The Spindle Assembly Checkpoint (SAC inhibits anaphase until microtubule-to-kinetochore attachments are formed, thus securing correct chromosome separation and preventing aneuploidy. Whereas in mitosis even a single unattached chromosome keeps the SAC active, the high incidence of aneuploidy related to maternal meiotic errors raises a concern about the lower efficiency of SAC in oocytes. Recently it was suggested that in mouse oocytes, contrary to somatic cells, not a single chromosome but a critical mass of chromosomes triggers efficient SAC pointing to the necessity of evaluating the robustness of SAC in oocytes. Two types of errors in chromosome segregation upon meiosis I related to SAC were envisaged: (1 SAC escape, when kinetochores emit SAC-activating signal unable to stop anaphase I; and (2 SAC deceive, when kinetochores do not emit the signal. Using micromanipulations and live imaging of the first polar body extrusion, as well as the dynamics of cyclin B1 degradation, here we show that in mouse oocytes a single bivalent keeps the SAC active. This is the first direct evaluation of SAC efficiency in mouse oocytes, which provides strong evidence that the robustness of SAC in mammalian oocytes is comparable to other cell types. Our data do not contradict the hypothesis of the critical mass of chromosomes necessary for SAC activation, but suggest that the same rule may govern SAC activity also in other cell types. We postulate that the innate susceptibility of oocytes to errors in chromosome segregation during the first meiotic division may not be caused by lower efficiency of SAC itself, but could be linked to high critical chromosome mass necessary to keep SAC active in oocyte of large size.

  2. Vpr14-88-Apobec3G fusion protein is efficiently incorporated into Vif-positive HIV-1 particles and inhibits viral infection.

    Science.gov (United States)

    Ao, Zhujun; Yu, Zhe; Wang, Lina; Zheng, Yingfeng; Yao, Xiaojian

    2008-04-16

    APOBEC3G (A3G), a deoxycytidine deaminase, is a potent host antiviral factor that can restrict HIV-1 infection. During Vif-negative HIV-1 replication, A3G is incorporated into HIV-1 particles, induces mutations in reverse transcribed viral DNA and inhibits reverse transcription. However, HIV-1 Vif counteracts A3G's activities by inducing its degradation and by blocking its incorporation into HIV-1 particles. Thus, it is interesting to elucidate a mechanism that would allow A3G to escape the effects of Vif in order to rescue its potent antiviral activity and to provide a possible novel therapeutic strategy for treating HIV-1 infection. In this study, we generated an R88-A3G fusion protein by fusing A3G to a virion-targeting polypeptide (R14-88) derived from HIV-1 Vpr protein and compared its antiviral effects relative to those of HA-tagged native A3G (HA-A3G). Our study showed that transient expression of the R88-A3G fusion protein in both Vif(-) and Vif(+) HIV-1 producing cells drastically inhibited viral infection in HeLa-CD4-CCR5-cells, CD4(+) C8166 T cells and human primary PBMCs. Moreover, we established CD4(+) C8166 T cell lines that stably express either R88-A3G or HA-A3G by transduction with VSV-G-pseudotyped lentiviral vector that harbor expression cassettes for R88-A3G or HA-A3G, respectively, and tested their susceptibility to Vif(+) HIV-1 infection. Our results clearly reveal that expression of R88-A3G in transduced CD4(+) C8166 cells significantly blocked Vif(+) HIV-1 infection. In an attempt to understand the mechanism underlying the antiviral activity of R88-A3G, we demonstrated that R88-A3G was efficiently incorporated into viral particles in the presence of Vif. Moreover, PCR analysis revealed that R88-A3G significantly inhibited viral cDNA synthesis during the early stage of Vif(+) virus infection. Our results clearly indicate that R88 delivers A3G into Vif(+) HIV-1 particles and inhibits infectivity and spread of the virions among CD4(+) T cells

  3. Efficient Inhibition of HIV Replication in the Gastrointestinal and Female Reproductive Tracts of Humanized BLT Mice by EFdA.

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    Uma Shanmugasundaram

    Full Text Available The nucleoside reverse transcriptase inhibitor (NRTI 4'-ethynyl-2-fluoro-2'-deoxyadenosine (EFdA in preclinical development exhibits improved safety and antiviral activity profiles with minimal drug resistance compared to approved NRTIs. However, the systemic antiviral efficacy of EFdA has not been fully evaluated. In this study, we utilized bone marrow/liver/thymus (BLT humanized mice to investigate the systemic effect of EFdA treatment on HIV replication and CD4+ T cell depletion in the peripheral blood (PB and tissues. In particular, we performed a comprehensive analysis of the female reproductive tract (FRT and gastrointestinal (GI tract, major sites of transmission, viral replication, and CD4+ T cell depletion and where some current antiretroviral drugs have a sub-optimal effect.EFdA treatment resulted in reduction of HIV-RNA in PB to undetectable levels in the majority of treated mice by 3 weeks post-treatment. HIV-RNA levels in cervicovaginal lavage of EFdA-treated BLT mice also declined to undetectable levels demonstrating strong penetration of EFdA into the FRT. Our results also demonstrate a strong systemic suppression of HIV replication in all tissues analyzed. In particular, we observed more than a 2-log difference in HIV-RNA levels in the GI tract and FRT of EFdA-treated BLT mice compared to untreated HIV-infected control mice. In addition, HIV-RNA was also significantly lower in the lymph nodes, liver, lung, spleen of EFdA-treated BLT mice compared to untreated HIV-infected control mice. Furthermore, EFdA treatment prevented the depletion of CD4+ T cells in the PB, mucosal tissues and lymphoid tissues.Our findings indicate that EFdA is highly effective in controlling viral replication and preserving CD4+ T cells in particular with high efficiency in the GI and FRT tract. Thus, EFdA represents a strong potential candidate for further development as a part of antiretroviral therapy regimens.

  4. Mouse Saliva Inhibits Transit of Influenza Virus to the Lower Respiratory Tract by Efficiently Blocking Influenza Virus Neuraminidase Activity.

    Science.gov (United States)

    Gilbertson, Brad; Ng, Wy Ching; Crawford, Simon; McKimm-Breschkin, Jenny L; Brown, Lorena E

    2017-07-15

    We previously identified a novel inhibitor of influenza virus in mouse saliva that halts the progression of susceptible viruses from the upper to the lower respiratory tract of mice in vivo and neutralizes viral infectivity in MDCK cells. Here, we investigated the viral target of the salivary inhibitor by using reverse genetics to create hybrid viruses with some surface proteins derived from an inhibitor-sensitive strain and others from an inhibitor-resistant strain. These viruses demonstrated that the origin of the viral neuraminidase (NA), but not the hemagglutinin or matrix protein, was the determinant of susceptibility to the inhibitor. Comparison of the NA sequences of a panel of H3N2 viruses with differing sensitivities to the salivary inhibitor revealed that surface residues 368 to 370 (N2 numbering) outside the active site played a key role in resistance. Resistant viruses contained an EDS motif at this location, and mutation to either EES or KDS, found in highly susceptible strains, significantly increased in vitro susceptibility to the inhibitor and reduced the ability of the virus to progress to the lungs when the viral inoculum was initially confined to the upper respiratory tract. In the presence of saliva, viral strains with a susceptible NA could not be efficiently released from the surfaces of infected MDCK cells and had reduced enzymatic activity based on their ability to cleave substrate in vitro This work indicates that the mouse has evolved an innate inhibitor similar in function, though not in mechanism, to what humans have created synthetically as an antiviral drug for influenza virus. IMPORTANCE Despite widespread use of experimental pulmonary infection of the laboratory mouse to study influenza virus infection and pathogenesis, to our knowledge, mice do not naturally succumb to influenza. Here, we show that mice produce their own natural form of neuraminidase inhibitor in saliva that stops the virus from reaching the lungs, providing a

  5. Efficient Recombinase-Mediated Cassette Exchange in hPSCs to Study the Hepatocyte Lineage Reveals AAVS1 Locus-Mediated Transgene Inhibition

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    Laura Ordovás

    2015-11-01

    Full Text Available Tools for rapid and efficient transgenesis in “safe harbor” loci in an isogenic context remain important to exploit the possibilities of human pluripotent stem cells (hPSCs. We created hPSC master cell lines suitable for FLPe recombinase-mediated cassette exchange (RMCE in the AAVS1 locus that allow generation of transgenic lines within 15 days with 100% efficiency and without random integrations. Using RMCE, we successfully incorporated several transgenes useful for lineage identification, cell toxicity studies, and gene overexpression to study the hepatocyte lineage. However, we observed unexpected and variable transgene expression inhibition in vitro, due to DNA methylation and other unknown mechanisms, both in undifferentiated hESC and differentiating hepatocytes. Therefore, the AAVS1 locus cannot be considered a universally safe harbor locus for reliable transgene expression in vitro, and using it for transgenesis in hPSC will require careful assessment of the function of individual transgenes.

  6. Co-inhibition of pol θ and HR genes efficiently synergize with cisplatin to suppress cisplatin-resistant lung cancer cells survival

    Science.gov (United States)

    Dai, Chun-Hua; Chen, Ping; Li, Jian; Lan, Tin; Chen, Yong-Chang; Qian, Hai; Chen, Kang; Li, Mei-Yu

    2016-01-01

    Cisplatin exert its anticancer effect by creating intrastrand and interstrand DNA cross-links which block DNA replication and is a major drug used to treat lung cancer. However, the main obstacle of the efficacy of treatment is drug resistance. Here, we show that expression of translesion synthesis (TLS) polymerase Q (POLQ) was significantly elevated by exposure of lung cancer cells A549/DR (a cisplatin-resistant A549 cell line) to cisplatin. POLQ expression correlated inversely with homologous recombination (HR) activity. Co-depletion of BRCA2 and POLQ by siRNA markedly increased sensitivity of A549/DR cells to cisplatin, which was accompanied with impairment of double strand breaks (DSBs) repair reflected by prominent cell cycle checkpoint response, increased chromosomal aberrations and persistent colocalization of p-ATM and 53BP1 foci induced by cisplatin. Thus, co-knockdown of POLQ and HR can efficiently synergize with cisplatin to inhibit A549/DR cell survival by inhibiting DNA DSBs repair. Similar results were observed in A549/DR cells co-depleted of BRCA2 and POLQ following BMN673 (a PARP inhibitor) treatment. Importantly, the sensitization effects to cisplatin and BMN673 in A549/DR cells by co-depleting BRCA2 and POLQ was stronger than those by co-depleting BRCA2 and other TLS factors including POLH, REV3, or REV1. Our results indicate that there is a synthetic lethal relationship between pol θ-mediated DNA repair and HR pathways. Pol θ may be considered as a novel target for lung cancer therapy. PMID:27533083

  7. Critical significance of the region between Helix 1 and 2 for efficient dominant-negative inhibition by conversion-incompetent prion protein.

    Directory of Open Access Journals (Sweden)

    Yuzuru Taguchi

    Full Text Available Prion diseases are fatal infectious neurodegenerative disorders in man and animals associated with the accumulation of the pathogenic isoform PrP(Sc of the host-encoded prion protein (PrP(c. A profound conformational change of PrP(c underlies formation of PrP(Sc and prion propagation involves conversion of PrP(c substrate by direct interaction with PrP(Sc template. Identifying the interfaces and modalities of inter-molecular interactions of PrPs will highly advance our understanding of prion propagation in particular and of prion-like mechanisms in general. To identify the region critical for inter-molecular interactions of PrP, we exploited here dominant-negative inhibition (DNI effects of conversion-incompetent, internally-deleted PrP (ΔPrP on co-expressed conversion-competent PrP. We created a series of ΔPrPs with different lengths of deletions in the region between first and second α-helix (H1∼H2 which was recently postulated to be of importance in prion species barrier and PrP fibril formation. As previously reported, ΔPrPs uniformly exhibited aberrant properties including detergent insolubility, limited protease digestion resistance, high-mannose type N-linked glycans, and intracellular localization. Although formerly controversial, we demonstrate here that ΔPrPs have a GPI anchor attached. Surprisingly, despite very similar biochemical and cell-biological properties, DNI efficiencies of ΔPrPs varied significantly, dependant on location and inversely correlated with the size of deletion. This data demonstrates that H1∼H2 and the region C-terminal to it are critically important for efficient DNI. It also suggests that this region is involved in PrP-PrP interaction and conversion of PrP(C into PrP(Sc. To reconcile the paradox of how an intracellular PrP can exert DNI, we demonstrate that ΔPrPs are subject to both proteasomal and lysosomal/autophagic degradation pathways. Using autophagy pathways ΔPrPs obtain access to the locale

  8. Inhibition of Pre-Supplementary Motor Area by Continuous Theta Burst Stimulation Leads to More Cautious Decision-making and More Efficient Sensory Evidence Integration.

    Science.gov (United States)

    Tosun, Tuğçe; Berkay, Dilara; Sack, Alexander T; Çakmak, Yusuf Ö; Balcı, Fuat

    2017-08-01

    Decisions are made based on the integration of available evidence. The noise in evidence accumulation leads to a particular speed-accuracy tradeoff in decision-making, which can be modulated and optimized by adaptive decision threshold setting. Given the effect of pre-SMA activity on striatal excitability, we hypothesized that the inhibition of pre-SMA would lead to higher decision thresholds and an increased accuracy bias. We used offline continuous theta burst stimulation to assess the effect of transient inhibition of the right pre-SMA on the decision processes in a free-response two-alternative forced-choice task within the drift diffusion model framework. Participants became more cautious and set higher decision thresholds following right pre-SMA inhibition compared with inhibition of the control site (vertex). Increased decision thresholds were accompanied by an accuracy bias with no effects on post-error choice behavior. Participants also exhibited higher drift rates as a result of pre-SMA inhibition compared with the vertex inhibition. These results, in line with the striatal theory of speed-accuracy tradeoff, provide evidence for the functional role of pre-SMA activity in decision threshold modulation. Our results also suggest that pre-SMA might be a part of the brain network associated with the sensory evidence integration.

  9. GAP--a PIC-type fluid code

    International Nuclear Information System (INIS)

    Marder, B.M.

    1975-01-01

    GAP, a PIC-type fluid code for computing compressible flows, is described and demonstrated. While retaining some features of PIC, it is felt that the GAP approach is conceptually and operationally simpler. 9 figures

  10. Development of a specific affinity-matured exosite inhibitor to MT1-MMP that efficiently inhibits tumor cell invasion in vitro and metastasis in vivo

    DEFF Research Database (Denmark)

    Botkjaer, Kenneth A; Kwok, Hang Fai; Terp, Mikkel G

    2016-01-01

    therapeutic target. Here, we report the identification of antibody fragments to MT1-MMP that potently and specifically inhibit its cell surface functions. Lead antibody clones displayed inhibitory activity towards pro-MMP-2 activation, collagen-film degradation and gelatin-film degradation, and were shown......The membrane-associated matrix metalloproteinase-14, MT1-MMP, has been implicated in pericellular proteolysis with an important role in cellular invasion of collagenous tissues. It is substantially upregulated in various cancers and rheumatoid arthritis, and has been considered as a potential...... to bind to the MT1-MMP catalytic domain outside the active site cleft, inhibiting binding to triple helical collagen. Affinity maturation using CDR3 randomization created a second generation of antibody fragments with dissociation constants down to 0.11 nM, corresponding to an improved affinity of 332...

  11. Efficient in vitro inhibition of HIV-1 gag reverse transcription by peptide nucleic acid (PNA) at minimal ratios of PNA/RNA

    DEFF Research Database (Denmark)

    Koppelhus, Uffe; Zachar, Vladimir; Nielsen, P.E.

    1997-01-01

    We have tested the inhibitory potential of peptide nucleic acid (PNA) on in vitro reverse transcription of the HIV-1 gag gene. PNA was designed to target different regions of the HIV-1 gag gene and the effect on reverse transcription by HIV-1, MMLV and AMV reverse transcriptases (RTs......) was investigated. We found that a bis-PNA (parallel antisense 10mer linked to antiparallel antisense 10mer) was superior to both the parallel antisense 10mer and antiparallel antisense 10mer in inhibiting reverse transcription of the gene, thus indicating triplex formation at the target sequence. A complete arrest...... of reverse transcription was obtained at approximately 6-fold molar excess of the bis-PNA with respect to the gag RNA. At this molar ratio we found no effect on in vitro translation of gag RNA. A 15mer duplex-forming PNA was also found to inhibit reverse transcription at very low molar ratios of PNA/ gag RNA...

  12. An Alginate/Cyclodextrin Spray Drying Matrix to ImproveShelf Lifeand Antioxidant Efficiency of a Blood Orange By-Product Extract Rich in Polyphenols: MMPs Inhibition and Antiglycation Activity in Dysmetabolic Diseases.

    Science.gov (United States)

    Lauro, Maria Rosaria; Crascì, Lucia; Giannone, Virgilio; Ballistreri, Gabriele; Fabroni, Simona; Sansone, Francesca; Rapisarda, Paolo; Panico, Anna Maria; Puglisi, Giovanni

    2017-01-01

    Alginate and β -cyclodextrin were used to produce easily dosable and spray-dried microsystems of a dried blood orange extract with antidysmetabolic properties, obtained from a by-product fluid extract. The spray-dried applied conditions were able to obtain a concentrate dried extract without the loss of AOA and with TPC and TMA values of 35-40% higher than that of the starting material. They were also effective in producing microparticles with 80-100% of encapsulation efficiency. The 2% sodium alginate was capable of improving the extract shelf life , while the beta-cyclodextrin (1 : 1 molar ratio with dried extract) prolonged the extract antioxidant efficiency by 6 hours. The good inhibition effect of the dried extract on the AGE formation and the MMP-2 and MMP-9 activity is presumably due to a synergic effect exerted by both anthocyanin and bioflavonoid extract compounds and was improved by the use of alginate and cyclodextrin.

  13. Efficient Synthesis of 2-Amino-6-Arylbenzothiazoles via Pd(0 Suzuki Cross Coupling Reactions: Potent Urease Enzyme Inhibition and Nitric Oxide Scavenging Activities of the Products

    Directory of Open Access Journals (Sweden)

    Md. Saiful Islam

    2013-07-01

    Full Text Available In general, benzothiazole derivatives have attracted great interest due to thier pharmaceutical and biological importance. New 2-amino-6-arylbenzothiazoles were synthesized in moderate to excellent yields via Suzuki cross coupling reactions using various aryl boronic acids and aryl boronic acid pinacol esters and the antiurease and nitric oxide (NO scavenging activity of the products were also examined. The most active compound concerning urease enzyme inhibition was 6-phenylbenzo[d]thiazole-2-amine 3e, with an IC50 value of 26.35 µg/mL. Compound 3c, 6-(4-methoxyphenyl benzo[d]thiazole-2-amine, exhibited the highest nitric oxide percentage scavenging at 100µg/mL.

  14. A Novel Neurotoxin Gene ar1b Recombination Enhances the Efficiency of Helicoverpa armigera Nucleopolyhedrovirus as a Pesticide by Inhibiting the Host Larvae Ability to Feed and Grow.

    Directory of Open Access Journals (Sweden)

    Huan Yu

    Full Text Available A recombinant Helicoverpa armigera nucleopolyhedrovirus (HearNPV, Ar1b-HearNPV, was constructed and identified as an improved bio-control agent of Helicoverpa armigera larvae. The HearNPV polyhedrin promoter was used to express the insect-specific neurotoxin gene, ar1b, which was originally isolated from the Australian funnel-web spider (Atrax robustus. RT-PCR and Western blotting analysis showed that both the ar1b transcript and protein were produced successfully in Ar1b-HearNPV-infected HzAM1 cells. In order to investigate the influence of foreign gene insertion in HearNPV, including the ar1b gene, chloramphenicol resistance gene, lacZ, kanamycin resistance gene, and the gentamicin resistance gene, two virus strains (HZ8-HearNPV and wt-HearNPV were used as controls in the cell transfection analysis. As expected, foreign gene insertion had no impact on budded virus production and viral DNA replication. Both optical microscopy and electron microscopy observations indicated that the formation of the occlusion bodies of recombinant virus was similar to wild type virus. The Ar1b-HearNPV-infected H. armigera larvae exhibited paralysis and weight loss before dying. This recombinant virus also showed a 32.87% decrease in LT50 assays compared with the wild type virus. Besides, Ar1b-HearNPV also inhibited host larval growth and diet consumption. This inhibition was still significant in the older instar larvae treated with the recombinant virus. All of these positive properties of this novel recombinant HearNPV provide a further opportunity to develop this virus strain into a commercial product to control the cotton bollworm.

  15. A Novel Neurotoxin Gene ar1b Recombination Enhances the Efficiency of Helicoverpa armigera Nucleopolyhedrovirus as a Pesticide by Inhibiting the Host Larvae Ability to Feed and Grow.

    Science.gov (United States)

    Yu, Huan; Meng, Jiao; Xu, Jian; Liu, Tong-Xian; Wang, Dun

    2015-01-01

    A recombinant Helicoverpa armigera nucleopolyhedrovirus (HearNPV), Ar1b-HearNPV, was constructed and identified as an improved bio-control agent of Helicoverpa armigera larvae. The HearNPV polyhedrin promoter was used to express the insect-specific neurotoxin gene, ar1b, which was originally isolated from the Australian funnel-web spider (Atrax robustus). RT-PCR and Western blotting analysis showed that both the ar1b transcript and protein were produced successfully in Ar1b-HearNPV-infected HzAM1 cells. In order to investigate the influence of foreign gene insertion in HearNPV, including the ar1b gene, chloramphenicol resistance gene, lacZ, kanamycin resistance gene, and the gentamicin resistance gene, two virus strains (HZ8-HearNPV and wt-HearNPV) were used as controls in the cell transfection analysis. As expected, foreign gene insertion had no impact on budded virus production and viral DNA replication. Both optical microscopy and electron microscopy observations indicated that the formation of the occlusion bodies of recombinant virus was similar to wild type virus. The Ar1b-HearNPV-infected H. armigera larvae exhibited paralysis and weight loss before dying. This recombinant virus also showed a 32.87% decrease in LT50 assays compared with the wild type virus. Besides, Ar1b-HearNPV also inhibited host larval growth and diet consumption. This inhibition was still significant in the older instar larvae treated with the recombinant virus. All of these positive properties of this novel recombinant HearNPV provide a further opportunity to develop this virus strain into a commercial product to control the cotton bollworm.

  16. Loss of GltB Inhibits Biofilm Formation and Biocontrol Efficiency of Bacillus subtilis Bs916 by Altering the Production of γ-Polyglutamate and Three Lipopeptides.

    Science.gov (United States)

    Zhou, Huafei; Luo, Chuping; Fang, Xianwen; Xiang, Yaping; Wang, Xiaoyu; Zhang, Rongsheng; Chen, Zhiyi

    2016-01-01

    This study examined the contribution of GltB on biofilm formation and biocontrol efficiency of B. subtilis Bs916. The gltB gene was identified through a biofilm phenotype screen and a bioinformatics analysis of serious biofilm formation defects, and then a gltB single knockout mutant was constructed using homologous recombination. This mutant demonstrated severe deficits in biofilm formation and colonisation along with significantly altered production ofγ-polyglutamate (γ-PGA) and three lipopeptide antibiotics (LPs) as measured by a transcriptional analysis of both the wild type B. subtilis Bs916 and the gltB mutant. Consequently, the mutant strain retained almost no antifungal activity against Rhizoctonia solani and exhibited decreased biocontrol efficiency against rice sheath blight. Very few gltB mutant cells colonised the rice stem, and they exhibited no significant nutrient chemotaxis compared to the wild type B. subtilis Bs916. The mechanism underlying these deficits in the gltB mutant appears to be decreased significantly in production of γ-PGA and a reduction in the production of both bacillomycin L and fengycin. Biofilm restoration of gltB mutant by additionγ-PGA in the EM medium demonstrated that biofilm formation was able to restore significantly at 20 g/L. GltB regulates biofilm formation by altering the production ofγ-PGA, the LPs bacillomycin L and fengcin and influences bacterial colonisation on the rice stem, which consequently leads to poor biocontrol efficiency against rice sheath blight. This is the first report of a key regulatory protein (GltB) that is involved in biofilm regulation and its regulation mechanism and biocontrol efficiency by B. subtilis.

  17. The inhibition and adaptability of four wetland plant species to high concentration of ammonia wastewater and nitrogen removal efficiency in constructed wetlands.

    Science.gov (United States)

    Wang, Yuhui; Wang, Junfeng; Zhao, Xiaoxiang; Song, Xinshan; Gong, Juan

    2016-02-01

    Four plant species, Typha orientalis, Scirpus validus, Canna indica and Iris tectorum were selected to assess their physiological response and effects on nitrogen and COD removal to high total ammoniacal nitrogen (TAN) in constructed wetlands. Results showed that high TAN caused decreased relative growth rate, net photosynthetic rate, and leaf transpiration. C. indica and T. orientalis showed higher TAN adaptability than S. validus and I. tectorum. Below TAN of 200 mg L(-1), growth of C. indica and T. orientalis was less affected or even stimulated at TAN range 100-200 mg L(-1). However, S. validus and I. tectorum was obviously suppressed when TAN was above 100 mg L(-1). High TAN generated obvious oxidative stress showing increased proline and malondialdehyde contents, and superoxide dismutase was inhibited. It indicated that the threshold for plant self-bioremediation against high TAN was 200 mg L(-1). What's more, planted CWs showed higher nitrogen and COD removal. Removal rate of C. indica and T. orientalis was higher than S. validus and I. tectorum. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Acylation of Antioxidant of Bamboo Leaves with Fatty Acids by Lipase and the Acylated Derivatives' Efficiency in the Inhibition of Acrylamide Formation in Fried Potato Crisps.

    Directory of Open Access Journals (Sweden)

    Xiang Ma

    Full Text Available This study selectively acylated the primary hydroxyl groups on flavonoids in antioxidant of bamboo leaves (AOB using lauric acid with Candida antarctica lipase B in tert-amyl-alcohol. The separation and isolation of acylated derivatives were performed using silica gel column chromatography with a mixture of dichloromethane/diethyl ether/methanol as eluents. Both thin layer chromatography and high-performance liquid chromatography analyses confirmed the high efficiency of the isolation process with the purified orientin-6″-laurate, isoorientin-6″-laurate, vitexin-6″-laurate, and isovitexin-6″-laurate that were obtained. The addition of AOB and acylated AOB reduced acrylamide formation in fried potato crisps. Results showed that 0.05% AOB and 0.05% and 0.1% acylated AOB groups significantly (p < 0.05 reduced the content of acrylamide in potato crisps by 30.7%, 44.5%, and 46.9%, respectively.

  19. Very low dose gamma irradiation stimulates gaseous exchange and carboxylation efficiency, but inhibits vascular sap flow in groundnut (Arachis hypogaea L.).

    Science.gov (United States)

    Ahuja, Sumedha; Singh, Bhupinder; Gupta, Vijay Kumar; Singhal, R K; Venu Babu, P

    2014-02-01

    An experiment was carried out to determine the effect of low dose gamma radiation on germination, plant growth, nitrogen and carbon fixation and carbon flow and release characteristics of groundnut. Dry seeds of groundnut variety Trombay groundnut 37A (TG 37A), a radio mutant type developed by Bhabha Atomic Research Centre (BARC), Mumbai, India, were subjected to the pre-sowing treatment of gamma radiation within low to high dose physiological range, i.e., 0.0, 0.0082, 0.0164. 0.0328, 0.0656, 0.1312, 5, 25, 100, 500 Gray (Gy) from a cobalt source ((60)Co). Observations were recorded for the radiation effect on percentage germination, vigour, gas exchange attributes such as photosynthetic rate, stomatal conductance and transpiration rate, chlorophyll content, root exudation in terms of (14)C release, vascular sap flow rate and activities of rate defining carbon and nitrogen assimilating enzymes such as ribulose-1,5-bisphosphate carboxylase (rubisco) and nitrate reductase (NR). Seed germination was increased by 10-25% at the lower doses up to 5 Gy while the improvement in plant vigour in the same dose range was much higher (22-84%) than the unirradiated control. For radiation exposure above 5 Gy, a dose-dependent decline in germination and plant vigour was measured. No significant effect was observed on the photosynthesis at radiation exposure below 5 Gy but above 5 Gy dose there was a decline in the photosynthetic rate. Stomatal conductance and transpiration rate, however, were only inhibited at a high dose of 500 Gy. Leaf rubisco activity and NR activities remained unaffected at all the investigated doses of gamma irradiation. Mean root exudation and sap flow rate of the irradiated plants, irrespective of the dose, was reduced over the unirradiated control more so in a dose-dependent manner. Results indicated that a very low dose of gamma radiation, in centigray to gray range, did not pose any threat and in fact stimulated metabolic functions in such a way to aid

  20. Rational design of novel N-alkyl-N capped biostable RNA nanostructures for efficient long-term inhibition of gene expression

    Science.gov (United States)

    Terrazas, Montserrat; Ivani, Ivan; Villegas, Núria; Paris, Clément; Salvans, Cándida; Brun-Heath, Isabelle; Orozco, Modesto

    2016-01-01

    Computational techniques have been used to design a novel class of RNA architecture with expected improved resistance to nuclease degradation, while showing interference RNA activity. The in silico designed structure consists of a 24–29 bp duplex RNA region linked on both ends by N-alkyl-N dimeric nucleotides (BCn dimers; n = number of carbon atoms of the alkyl chain). A series of N-alkyl-N capped dumbbell-shaped structures were efficiently synthesized by double ligation of BCn-loop hairpins. The resulting BCn-loop dumbbells displayed experimentally higher biostability than their 3′-N-alkyl-N linear version, and were active against a range of mRNA targets. We studied first the effect of the alkyl chain and stem lengths on RNAi activity in a screen involving two series of dumbbell analogues targeting Renilla and Firefly luciferase genes. The best dumbbell design (containing BC6 loops and 29 bp) was successfully used to silence GRB7 expression in HER2+ breast cancer cells for longer periods of time than natural siRNAs and known biostable dumbbells. This BC6-loop dumbbell-shaped structure displayed greater anti-proliferative activity than natural siRNAs. PMID:26975656

  1. An Alginate/Cyclodextrin Spray Drying Matrix to Improve Shelf Life and Antioxidant Efficiency of a Blood Orange By-Product Extract Rich in Polyphenols: MMPs Inhibition and Antiglycation Activity in Dysmetabolic Diseases

    Science.gov (United States)

    Giannone, Virgilio; Ballistreri, Gabriele; Fabroni, Simona; Rapisarda, Paolo; Panico, Anna Maria; Puglisi, Giovanni

    2017-01-01

    Alginate and β-cyclodextrin were used to produce easily dosable and spray-dried microsystems of a dried blood orange extract with antidysmetabolic properties, obtained from a by-product fluid extract. The spray-dried applied conditions were able to obtain a concentrate dried extract without the loss of AOA and with TPC and TMA values of 35–40% higher than that of the starting material. They were also effective in producing microparticles with 80–100% of encapsulation efficiency. The 2% sodium alginate was capable of improving the extract shelf life, while the beta-cyclodextrin (1 : 1 molar ratio with dried extract) prolonged the extract antioxidant efficiency by 6 hours. The good inhibition effect of the dried extract on the AGE formation and the MMP-2 and MMP-9 activity is presumably due to a synergic effect exerted by both anthocyanin and bioflavonoid extract compounds and was improved by the use of alginate and cyclodextrin. PMID:29230268

  2. An Alginate/Cyclodextrin Spray Drying Matrix to Improve Shelf Life and Antioxidant Efficiency of a Blood Orange By-Product Extract Rich in Polyphenols: MMPs Inhibition and Antiglycation Activity in Dysmetabolic Diseases

    Directory of Open Access Journals (Sweden)

    Maria Rosaria Lauro

    2017-01-01

    Full Text Available Alginate and β-cyclodextrin were used to produce easily dosable and spray-dried microsystems of a dried blood orange extract with antidysmetabolic properties, obtained from a by-product fluid extract. The spray-dried applied conditions were able to obtain a concentrate dried extract without the loss of AOA and with TPC and TMA values of 35–40% higher than that of the starting material. They were also effective in producing microparticles with 80–100% of encapsulation efficiency. The 2% sodium alginate was capable of improving the extract shelf life, while the beta-cyclodextrin (1 : 1 molar ratio with dried extract prolonged the extract antioxidant efficiency by 6 hours. The good inhibition effect of the dried extract on the AGE formation and the MMP-2 and MMP-9 activity is presumably due to a synergic effect exerted by both anthocyanin and bioflavonoid extract compounds and was improved by the use of alginate and cyclodextrin.

  3. Transmitted/founder and chronic subtype C HIV-1 use CD4 and CCR5 receptors with equal efficiency and are not inhibited by blocking the integrin α4β7.

    Directory of Open Access Journals (Sweden)

    Nicholas F Parrish

    Full Text Available Sexual transmission of human immunodeficiency virus type 1 (HIV-1 most often results from productive infection by a single transmitted/founder (T/F virus, indicating a stringent mucosal bottleneck. Understanding the viral traits that overcome this bottleneck could have important implications for HIV-1 vaccine design and other prevention strategies. Most T/F viruses use CCR5 to infect target cells and some encode envelope glycoproteins (Envs that contain fewer potential N-linked glycosylation sites and shorter V1/V2 variable loops than Envs from chronic viruses. Moreover, it has been reported that the gp120 subunits of certain transmitted Envs bind to the gut-homing integrin α4β7, possibly enhancing virus entry and cell-to-cell spread. Here we sought to determine whether subtype C T/F viruses, which are responsible for the majority of new HIV-1 infections worldwide, share biological properties that increase their transmission fitness, including preferential α4β7 engagement. Using single genome amplification, we generated panels of both T/F (n = 20 and chronic (n = 20 Env constructs as well as full-length T/F (n = 6 and chronic (n = 4 infectious molecular clones (IMCs. We found that T/F and chronic control Envs were indistinguishable in the efficiency with which they used CD4 and CCR5. Both groups of Envs also exhibited the same CD4+ T cell subset tropism and showed similar sensitivity to neutralization by CD4 binding site (CD4bs antibodies. Finally, saturating concentrations of anti-α4β7 antibodies failed to inhibit infection and replication of T/F as well as chronic control viruses, although the growth of the tissue culture-adapted strain SF162 was modestly impaired. These results indicate that the population bottleneck associated with mucosal HIV-1 acquisition is not due to the selection of T/F viruses that use α4β7, CD4 or CCR5 more efficiently.

  4. Effect of Adenine Concentration on the Corrosion Inhibition of Aisi ...

    African Journals Online (AJOL)

    This gave a surface coverage of 0.8956 and corrosion penetration rate of 0.022132mm/yr. Hence, the best adenine concentration for the corrosion inhibition of alloys 304L in 1.0M sulphuric acid solution to obtain optimum inhibition efficiency is 0.011M. Keywords: Corrosion, AISI 304L Steel, Inhibition efficiency, Degree of ...

  5. Adsorptive, Kinetic, Thermodynamic and Inhibitive Properties of ...

    African Journals Online (AJOL)

    The adsorption of Cissus populnea stem extract and its subsequent corrosion inhibition properties on aluminum in 0.5 M HCl solutions have been investigated using weight loss measurements. Inhibition efficiency of the plant extract increased with concentration but decreased with rise in temperature. The adsorption of the ...

  6. Inhibition and Adsorption impact of Leave Extracts of Cnidoscolus ...

    African Journals Online (AJOL)

    Corrosion inhibition in the presence of alokaloid and non alkaloid extracts of Cnidoscolus aconitifolius in 1M HCl was studied using the weight loss and hydrogen evolution techniques at 303, 313 and 333 K. The results obtained revealed that the inhibition efficiency decreased with increase in temperature. Inhibition ...

  7. Energy efficiency

    International Nuclear Information System (INIS)

    2010-01-01

    After a speech of the CEA's (Commissariat a l'Energie Atomique) general administrator about energy efficiency as a first rank challenge for the planet and for France, this publications proposes several contributions: a discussion of the efficiency of nuclear energy, an economic analysis of R and D's value in the field of fourth generation fast reactors, discussions about biofuels and the relationship between energy efficiency and economic competitiveness, and a discussion about solar photovoltaic efficiency

  8. INHIBITION IN SPEAKING PERFORMANCE

    Directory of Open Access Journals (Sweden)

    Isna Humaera

    2015-09-01

    Full Text Available The most common problem encountered by the learner in the language acquisition process is learner inhibition. Inhibition refers to a temperamental tendency to display wariness, fearfulness, or restrain in response to unfamiliar people, objects, and situations. There are some factors that cause inhibition, such as lack of motivation, shyness, self-confidence, self-esteem, and language ego. There are also levels of inhibition, it refers to kinds of inhibition and caused of inhibition itself. Teacher can support their students to reduce their inhibition effect by many ways, one of them by creating good classroom management including establishing good rapport between teacher and learners.

  9. BST2/Tetherin Inhibition of Alphavirus Exit

    Directory of Open Access Journals (Sweden)

    Yaw Shin Ooi

    2015-04-01

    Full Text Available Alphaviruses such as chikungunya virus (CHIKV and Semliki Forest virus (SFV are small enveloped RNA viruses that bud from the plasma membrane. Tetherin/BST2 is an interferon-induced host membrane protein that inhibits the release of many enveloped viruses via direct tethering of budded particles to the cell surface. Alphaviruses have highly organized structures and exclude host membrane proteins from the site of budding, suggesting that their release might be insensitive to tetherin inhibition. Here, we demonstrated that exogenously-expressed tetherin efficiently inhibited the release of SFV and CHIKV particles from host cells without affecting virus entry and infection. Alphavirus release was also inhibited by the endogenous levels of tetherin in HeLa cells. While rubella virus (RuV and dengue virus (DENV have structural similarities to alphaviruses, tetherin inhibited the release of RuV but not DENV. We found that two recently identified tetherin isoforms differing in length at the N-terminus exhibited distinct capabilities in restricting alphavirus release. SFV exit was efficiently inhibited by the long isoform but not the short isoform of tetherin, while both isoforms inhibited vesicular stomatitis virus exit. Thus, in spite of the organized structure of the virus particle, tetherin specifically blocks alphavirus release and shows an interesting isoform requirement.

  10. Evaluation of polymer efficiency on the inhibition of calcium carbonate scale in synthetic brines; Avaliacao da acao de polimeros sobre a inibicao de incrustacoes de carbonato de calcio em salmouras sinteticas

    Energy Technology Data Exchange (ETDEWEB)

    Freitas, Juliana M.; Rodrigues, Jessica S.; Loureiro, Tatiana S.; Lucas, Elizabete F.; Spinelli, Luciana S. [Universidade Federal do Rio de Janeiro, Instituto de Macromoleculas, Laboratorio de Macromoleculas e Coloides na Industria de Petroleo, RJ (Brazil)], e-mail: julianamatos@ima.ufrj.br

    2011-07-01

    The inorganic scale results in serious problems for oil production. This scale results from the incompatibility between the chemical compositions of formation water and injection, and the changes of thermodynamic system. These deposits consist mainly of calcium carbonate and barium sulfate. In order to prevent the formation of these deposits, the petroleum industry has made use of chemicals that act as scale inhibitors. The aim of this study was to test the ability of two types of polymeric inhibitors prevent the formation of calcium carbonate from brines of different compositions with high concentrations of calcium. The inhibitors were tested at varying concentrations and at fixed conditions of temperature, pH, pressure and time. The estimated effectiveness of each inhibitor was measured by complexometric titration. The inhibitor carboxylic acid-based (poly (maleic acid)) was more efficient at relatively low concentrations, which is important both economically and environmentally. (author)

  11. Bellman's GAP--a language and compiler for dynamic programming in sequence analysis.

    Science.gov (United States)

    Sauthoff, Georg; Möhl, Mathias; Janssen, Stefan; Giegerich, Robert

    2013-03-01

    Dynamic programming is ubiquitous in bioinformatics. Developing and implementing non-trivial dynamic programming algorithms is often error prone and tedious. Bellman's GAP is a new programming system, designed to ease the development of bioinformatics tools based on the dynamic programming technique. In Bellman's GAP, dynamic programming algorithms are described in a declarative style by tree grammars, evaluation algebras and products formed thereof. This bypasses the design of explicit dynamic programming recurrences and yields programs that are free of subscript errors, modular and easy to modify. The declarative modules are compiled into C++ code that is competitive to carefully hand-crafted implementations. This article introduces the Bellman's GAP system and its language, GAP-L. It then demonstrates the ease of development and the degree of re-use by creating variants of two common bioinformatics algorithms. Finally, it evaluates Bellman's GAP as an implementation platform of 'real-world' bioinformatics tools. Bellman's GAP is available under GPL license from http://bibiserv.cebitec.uni-bielefeld.de/bellmansgap. This Web site includes a repository of re-usable modules for RNA folding based on thermodynamics.

  12. Eight nucleotide substitutions inhibit splicing to HPV-16 3'-splice site SA3358 and reduce the efficiency by which HPV-16 increases the life span of primary human keratinocytes.

    Directory of Open Access Journals (Sweden)

    Xiaoze Li

    Full Text Available The most commonly used 3'-splice site on the human papillomavirus type 16 (HPV-16 genome named SA3358 is used to produce HPV-16 early mRNAs encoding E4, E5, E6 and E7, and late mRNAs encoding L1 and L2. We have previously shown that SA3358 is suboptimal and is totally dependent on a downstream splicing enhancer containingmultiple potential ASF/SF2 binding sites. Here weshow that only one of the predicted ASF/SF2 sites accounts for the majority of the enhancer activity. We demonstrate that single nucleotide substitutions in this predicted ASF/SF2 site impair enhancer function and that this correlates with less efficient binding to ASF/SF2 in vitro. We provide evidence that HPV-16 mRNAs that arespliced to SA3358 interact with ASF/SF2 in living cells. In addition,mutational inactivation of the ASF/SF2 site weakened the enhancer at SA3358 in episomal forms of the HPV-16 genome, indicating that the enhancer is active in the context of the full HPV-16 genome.This resulted in induction of HPV-16 late gene expression as a result of competition from late splice site SA5639. Furthermore, inactivation of the ASF/SF2 site of the SA3358 splicing enhancer reduced the ability of E6- and E7-encoding HPV-16 plasmids to increase the life span of primary keratinocytes in vitro, demonstrating arequirement for an intact splicing enhancer of SA3358 forefficient production of the E6 and E7 mRNAs. These results link the strength of the HPV-16 SA3358 splicing enhancer to expression of E6 and E7 and to the pathogenic properties of HPV-16.

  13. Batch efficiency

    International Nuclear Information System (INIS)

    Schwickerath, Ulrich; Silva, Ricardo; Uria, Christian

    2010-01-01

    A frequent source of concern for resource providers is the efficient use of computing resources in their centers. This has a direct impact on requests for new resources. There are two different but strongly correlated aspects to be considered: while users are mostly interested in a good turn-around time for their jobs, resource providers are mostly interested in a high and efficient usage of their available resources. Both things, the box usage and the efficiency of individual user jobs, need to be closely monitored so that the sources of the inefficiencies can be identified. At CERN, the Lemon monitoring system is used for both purposes. Examples of such sources are poorly written user code, inefficient access to mass storage systems, and dedication of resources to specific user groups. As a first step for improvements CERN has launched a project to develop a scheduler add-on that allows careful overloading of worker nodes that run idle jobs.

  14. Inhibition of urinary calculi -- a spectroscopic study

    Science.gov (United States)

    Manciu, Felicia; Govani, Jayesh; Durrer, William; Reza, Layra; Pinales, Luis

    2008-10-01

    Although a considerable number of investigations have already been undertaken and many causes such as life habits, metabolic disorders, and genetic factors have been noted as sources that accelerate calculi depositions and aggregations, there are still plenty of unanswered questions regarding efficient inhibition and treatment mechanisms. Thus, in an attempt to acquire more insights, we propose here a detailed scientific study of kidney stone formation and growth inhibition based on a traditional medicine approach with Rotula Aquatica Lour (RAL) herbal extracts. A simplified single diffusion gel growth technique was used for synthesizing the samples for the present study. The unexpected Zn presence in the sample with RAL inhibitor, as revealed by XPS measurements, explains the inhibition process and the dramatic reflectance of the incident light observed in the infrared transmission studies. Raman data demonstrate potential binding of the inhibitor with the oxygen of the kidney stone. Photoluminescence results corroborate to provide additional evidence of Zn-related inhibition.

  15. INHIBITION OF THE CORROSION OF MILD STEEL IN ...

    African Journals Online (AJOL)

    ABSTRACT. The inhibition of corrosion of mild steel in hydrochloric acid by isatin glycine (ING) and isatin (IN) at 30-60 oC and concentrations of 0.0001 M to 0.0005 M was studied via weight loss method. At the highest inhibitor concentration studied ING exhibited inhibition efficiency of 87% while IN exhibited 84% at 60 oC.

  16. Efficient ICT for efficient smart grids

    NARCIS (Netherlands)

    Smit, Gerardus Johannes Maria

    2012-01-01

    In this extended abstract the need for efficient and reliable ICT is discussed. Efficiency of ICT not only deals with energy-efficient ICT hardware, but also deals with efficient algorithms, efficient design methods, efficient networking infrastructures, etc. Efficient and reliable ICT is a

  17. The role of (dis)inhibition in creativity: decreased inhibition improves idea generation.

    Science.gov (United States)

    Radel, Rémi; Davranche, Karen; Fournier, Marion; Dietrich, Arne

    2015-01-01

    There is now a large body of evidence showing that many different conditions related to impaired fronto-executive functioning are associated with the enhancement of some types of creativity. In this paper, we pursue the possibility that the central mechanism associated with this effect might be a reduced capacity to exert inhibition. We tested this hypothesis by exhausting the inhibition efficiency through prolonged and intensive practice of either the Simon or the Eriksen Flanker task. Performance on another inhibition task indicated that only the cognitive resources for inhibition of participants facing high inhibition demands were impaired. Subsequent creativity tests revealed that exposure to high inhibition demands led to enhanced fluency in a divergent thinking task (Alternate Uses Task), but no such changes occurred in a convergent task (Remote Associate Task; studies 1a and 1b). The same manipulation also led to a hyper-priming effect for weakly related primes in a Lexical Decision Task (Study 2). Together, these findings suggest that inhibition selectively affects some types of creative processes and that, when resources for inhibition are lacking, the frequency and the originality of ideas was facilitated. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Offsetting efficiency

    International Nuclear Information System (INIS)

    Katz, M.

    1995-01-01

    Whichever way the local distribution company (LDC) tries to convert residential customers to gas or expand their use of it, the process itself has become essential for the natural gas industry. The amount of gas used by each residential customer has been decreasing for 25 years -- since the energy crisis of the early 1970s. It's a direct result of better-insulated homes and more-efficient gas appliances, and that trend is continuing. So, LDCs have a choice of either finding new users and uses for gas, or recognizing that their throughput per customer is going to continue declining. The paper discusses strategies that several gas utilities are using to increase the number of gas appliances in the customer's homes. These and other strategies keep the gas industry optimistic about the future of the residential market: A.G.A. has projected that by 2010 demand will expand, from 1994's 5.1 quadrillion Btu (quads) to 5.7 quads, even with continued improvements in appliance efficiency. That estimate, however, will depend on the industry-s utilities and whether they keep converting, proselytizing, persuading and influencing customers to use more natural gas

  19. Inhibition of aluminum corrosion using Opuntia extract

    Energy Technology Data Exchange (ETDEWEB)

    El-Etre, A.Y

    2003-11-01

    The inhibitive action of the mucilage extracted from the modified stems of prickly pears, toward acid corrosion of aluminum, is tested using weight loss, thermometry, hydrogen evolution and polarization techniques. It was found that the extract acts as a good corrosion inhibitor for aluminum corrosion in 2.0 M HCl solution. The inhibition action of the extract was discussed in view of Langmuir adsorption isotherm. It was found that the adsorption of the extract on aluminum surface is a spontaneous process. The inhibition efficiency (IE) increases as the extract concentration is increased. The effect of temperature on the IE was studied. It was found that the presence of extract increases the activation energy of the corrosion reaction. Moreover, the thermodynamic parameters of the adsorption process were calculated. It was found also that the Opuntia extract provides a good protection to aluminum against pitting corrosion in chloride ion containing solutions.

  20. Efficient STFT

    International Nuclear Information System (INIS)

    Aamir, K.M.; Maud, M.A.

    2004-01-01

    Small perturbations in signals (or any time series), at some particular instant, affect the whole frequency spectrum due to the global function e/sup j omega t/ in Fourier Transform formulation. However, the Fourier spectrum does not convey the time instant at which the perturbation occurred. Consequently the information on the particular time instance of occurrence of that perturbation is lost when spectrum is observed. Apparently Fourier analysis seems to be inadequate in such situations. This inadequacy is overcome by the use of Short Time Fourier Transform (STFT), which keeps track of time as well as frequency information. In STFT analysis, a fixed length window, say of length N, is moved sample by sample as the data arrives. The Discrete Fourier Transform (DFT) of this fixed window of length N is calculated using Fast Fourier Transform (FFT) algorithm. If the total number of points is M > N, the computational complexity of this scheme works out to be at least ((M-N) N log/sub 2/N). On the other hand, STFT is shown to be of computational complexity 6NM and 8NM in the literature. In this paper, two algorithms are presented which compute the same STFT more efficiently. The computational complexity of the proposed algorithms works out to be MN of one algorithm and even lesser in the other algorithm. This reduction in complexity becomes significant for large data sets. This algorithm also remains valid if a stationary part of signal is skipped. (author)

  1. Inhibition of Corrosion of Zinc in (HNO 3 + HCl) acid mixture by ...

    African Journals Online (AJOL)

    Corrosion of Zinc metal in (HNO3 + HCl) binary acid mixture and inhibition efficiency of aniline has been studied by weight loss method and polarization technique. Corrosion rate increases with the concentration of acid mixture and the temperature. Inhibition efficiency (I.E.) of aniline increases with the concentration of ...

  2. Corrosion inhibition of mild steel in 1 M HCl solution by henna extract: A comparative study of the inhibition by henna and its constituents (Lawsone, Gallic acid, {alpha}-D-Glucose and Tannic acid)

    Energy Technology Data Exchange (ETDEWEB)

    Ostovari, A. [Technical Inspection Engineering Department, Petroleum University of Technology, Abadan (Iran, Islamic Republic of)], E-mail: A.Ostovari@gmail.com; Hoseinieh, S.M.; Peikari, M. [Technical Inspection Engineering Department, Petroleum University of Technology, Abadan (Iran, Islamic Republic of); Shadizadeh, S.R. [Petroleum Engineering Department, Petroleum University of Technology, Abadan (Iran, Islamic Republic of); Hashemi, S.J. [Technical Inspection Engineering Department, Petroleum University of Technology, Abadan (Iran, Islamic Republic of)

    2009-09-15

    The inhibitive action of henna extract (Lawsonia inermis) and its main constituents (lawsone, gallic acid, {alpha}-D-Glucose and tannic acid) on corrosion of mild steel in 1 M HCl solution was investigated through electrochemical techniques and surface analysis (SEM/EDS). Polarization measurements indicate that all the examined compounds act as a mixed inhibitor and inhibition efficiency increases with inhibitor concentration. Maximum inhibition efficiency (92.06%) is obtained at 1.2 g/l henna extract. Inhibition efficiency increases in the order: lawsone > henna extract > gallic acid > {alpha}-D-Glucose > tannic acid. Also, inhibition mechanism and thermodynamic parameters are discussed.

  3. TV Inhibiting Creative Ideas

    Science.gov (United States)

    Intellect, 1977

    1977-01-01

    Television may be inhibiting our ability to create new ideas, according to Eric Somers, assistant professor of journalism at Drake University. Discusses television's role as facilitator of information and how it should improve to increase organization and the creative process. (Editor/RK)

  4. Enzyme inhibition by iminosugars

    DEFF Research Database (Denmark)

    López, Óscar; Qing, Feng-Ling; Pedersen, Christian Marcus

    2013-01-01

    Imino- and azasugar glycosidase inhibitors display pH dependant inhibition reflecting that both the inhibitor and the enzyme active site have groups that change protonation state with pH. With the enzyme having two acidic groups and the inhibitor one basic group, enzyme-inhibitor complexes...

  5. Inhibiting the inevitable

    DEFF Research Database (Denmark)

    Shashoua, Yvonne

    2006-01-01

    conservation is to ‘buy time’ for the object. Inhibitive conservation of plastics involves the removal or reduction of factors causing or accelerating degradation including light, oxygen, acids, relative humidity and acidic breakdown products. Specific approaches to conservation have been developed......Once plastics objects are registered in museum collections, the institution becomes responsible for their long term preservation, until the end of their useful lifetime. Plastics appear to deteriorate faster than other materials in museum collections and have a useful lifetime between 5 and 25...... years. Preventive or inhibitive conservation involves controlling the environments in which objects are placed during storage and display, with the aim of slowing the major deterioration reactions. Once in progress, degradation of plastics cannot be stopped or reversed, so the aim of preventive...

  6. Plastics for corrosion inhibition

    CERN Document Server

    Goldade, Victor A; Makarevich, Anna V; Kestelman, Vladimir N

    2005-01-01

    The development of polymer composites containing inhibitors of metal corrosion is an important endeavour in modern materials science and technology. Corrosion inhibitors can be located in a polymer matrix in the solid, liquid or gaseous phase. This book details the thermodynamic principles for selecting these components, their compatibility and their effectiveness. The various mechanisms of metal protection – barrier, inhibiting and electromechanical – are considered, as are the conflicting requirements placed on the structure of the combined material. Two main classes of inhibited materials (structural and films/coatings) are described in detail. Examples are given of structural plastics used in friction units subjected to mechano-chemical wear and of polymer films/coatings for protecting metal objects against corrosion.

  7. Mechanism of acid corrosion inhibition using magnetic nanofluid

    Science.gov (United States)

    Parekh, Kinnari; Jauhari, Smita; Upadhyay, R. V.

    2016-12-01

    The inhibition effect of magnetic nanofluid on carbon steel in acid solutions was investigated using gravimetric, potentiodynamic and SEM measurement. The inhibition efficiency increases up to 95% and 75% for 51.7 mM concentration, respectively, in 1 M HCl and 1 M H2SO4 medium. The adsorption of nanoparticles to the steel surface forms a barrier between the metal and the aggressive environment, which is responsible for observed inhibition action. The adsorption of nanoparticles on steel surface is supported by the Langmuir and Freundlich adsorption isotherm and surface morphology scanned through SEM.

  8. Technical efficiency, efficiency change, technical progress and ...

    African Journals Online (AJOL)

    Technical efficiency, efficiency change, technical progress and productivity growth in the national health systems of continental African countries. ... a view to analysing changes in efficiency and changes in technology. The analysis was based on a five-year panel data (1999-2003) from all the 53 countries of continental ...

  9. Inhibition of lignin-derived phenolic compounds to cellulase.

    Science.gov (United States)

    Qin, Lei; Li, Wen-Chao; Liu, Li; Zhu, Jia-Qing; Li, Xia; Li, Bing-Zhi; Yuan, Ying-Jin

    2016-01-01

    Lignin-derived phenolic compounds are universal in the hydrolysate of pretreated lignocellulosic biomass. The phenolics reduce the efficiency of enzymatic hydrolysis and increase the cost of ethanol production. We investigated inhibition of phenolics on cellulase during enzymatic hydrolysis using vanillin as one of the typical lignin-derived phenolics and Avicel as cellulose substrate. As vanillin concentration increased from 0 to 10 mg/mL, cellulose conversion after 72-h enzymatic hydrolysis decreased from 53 to 26 %. Enzyme deactivation and precipitation were detected with the vanillin addition. The enzyme concentration and activity consecutively decreased during hydrolysis, but the inhibition degree, expressed as the ratio of the cellulose conversion without vanillin to the conversion with vanillin (A 0 /A), was almost independent on hydrolysis time. Inhibition can be mitigated by increasing cellulose loading or cellulase concentration. The inhibition degree showed linear relationship with the vanillin concentration and exponential relationship with the cellulose loading and the cellulase concentration. The addition of calcium chloride, BSA, and Tween 80 did not release the inhibition of vanillin significantly. pH and temperature for hydrolysis also showed no significant impact on inhibition degree. The presence of hydroxyl group, carbonyl group, and methoxy group in phenolics affected the inhibition degree. Besides phenolics concentration, other factors such as cellulose loading, enzyme concentration, and phenolic structure also affect the inhibition of cellulose conversion. Lignin-blocking agents have little effect on the inhibition effect of soluble phenolics, indicating that the inhibition mechanism of phenolics to enzyme is likely different from insoluble lignin. The inhibition of soluble phenolics can hardly be entirely removed by increasing enzyme concentration or adding blocking proteins due to the dispersity and multiple binding sites of phenolics

  10. Paraquat inhibits progesterone synthesis in human placental mitochondria.

    Science.gov (United States)

    Milczarek, Ryszard; Sokołowska, Ewa; Rybakowska, Iwona; Kaletha, Krystian; Klimek, Jerzy

    2016-07-01

    Human placenta mitochondria produces huge amounts of progesterone necessary for maintaining the pregnancy. Lipid peroxidation in human placental mitochondria inhibits progesterone synthesis and that inhibition can be reversed by superoxide dismutase and other antioxidants. Paraquat (PQ) a highly toxic herbicide generates superoxide radical inside cells and induces lipid peroxidation. Hence, it is supposed to stimulate lipid peroxidation in human placental mitochondria and in consequence to inhibit a placental mitochondrial steroidogenesis. Placentas were obtained from normal pregnancies. All experiments were done using isolated human placental mitochondria. Mitochondrial lipid peroxidation was determined as tiobarbituric acid reactive substances (TBARS). A conversion of cholesterol to pregnenolone or pregnenolone to progesterone was measured using radiolabeled steroids and thin layer chromatography. PQ enhanced the iron-dependent lipid peroxidation as also PQ heightened the inhibitory action of this process on progesterone synthesis in isolated human placental mitochondria. Paradoxically, a superoxide dismutase (SOD) reversed the inhibition of progesterone synthesis only minimally although it strongly inhibited PQ stimulated iron-dependent lipid peroxidation. When iron was absent, PQ stimulated only negligible lipid peroxidation but strongly inhibited progesterone synthesis. SOD had no effect on inhibition of progesterone synthesis by PQ. PQ strongly inhibited of the conversion of cholesterol to pregnenolone but had not got any influence on the enzymatic activity of mitochondrial 3β-hydroxysteroid dehydrogenase. PQ strongly decreased the efficiency of NADPH-dependent cytochrome P450 reduction as well as it promoted the rapid oxidation of the pre-reduced mitochondrial cytochrome P450. However PQ has not inhibited combined activity of adrenodoxin reductase and adrenodoxin. We conclude that the most important reason of the inhibition of progesterone synthesis by PQ

  11. Beneficial bacteria inhibit cachexia

    Science.gov (United States)

    Varian, Bernard J.; Goureshetti, Sravya; Poutahidis, Theofilos; Lakritz, Jessica R.; Levkovich, Tatiana; Kwok, Caitlin; Teliousis, Konstantinos; Ibrahim, Yassin M.; Mirabal, Sheyla; Erdman, Susan E.

    2016-01-01

    Muscle wasting, known as cachexia, is a debilitating condition associated with chronic inflammation such as during cancer. Beneficial microbes have been shown to optimize systemic inflammatory tone during good health; however, interactions between microbes and host immunity in the context of cachexia are incompletely understood. Here we use mouse models to test roles for bacteria in muscle wasting syndromes. We find that feeding of a human commensal microbe, Lactobacillus reuteri, to mice is sufficient to lower systemic indices of inflammation and inhibit cachexia. Further, the microbial muscle-building phenomenon extends to normal aging as wild type animals exhibited increased growth hormone levels and up-regulation of transcription factor Forkhead Box N1 [FoxN1] associated with thymus gland retention and longevity. Interestingly, mice with a defective FoxN1 gene (athymic nude) fail to inhibit sarcopenia after L. reuteri therapy, indicating a FoxN1-mediated mechanism. In conclusion, symbiotic bacteria may serve to stimulate FoxN1 and thymic functions that regulate inflammation, offering possible alternatives for cachexia prevention and novel insights into roles for microbiota in mammalian ontogeny and phylogeny. PMID:26933816

  12. Inhibition of Intrinsic Thrombin Generation

    Directory of Open Access Journals (Sweden)

    Thomas W. Stief MD

    2006-01-01

    Full Text Available Background The contact phase of coagulation is of physiologic/pathophysiologic importance, whenever unphysiologic polynegative substances such as cell fragments (microparticles get in contact with blood. There are several clinically used inhibitors of intrinsic thrombin generation. Here the inhibitory concentrations 50% (IC50 of these anticoagulants are measured by the highly specific thrombin generation assay INCA. Methods Unfrozen pooled normal citrated plasma in polystyrole tubes was supplemented at 23°C in duplicate with 0–2 IU/ml low molecular weight heparin (dalteparin, 0–2 IU/ml unfractionated heparin, 0–500 KIU/ml aprotinin, or 0–40 mM arginine. 50 μl plasma or 1 IU/ml thrombin standard were pipetted into a polystyrole microtiter plate with flat bottom. 5 μl SiO 2 /CaCl 2 - reagent (INCA activator were added and after 0–30 min incubation at 37°C 100 μl 2.5 M arginine, pH 8.6, were added; arginine inhibits hemostasis activation and depolymerizes generated fibrin within 20 min at 23°C. The in the physiologic 37°C incubation phase generated thrombin was then chromogenically detected. The intra-assay CV values were < 5%. Results and Discussion The approximate IC50 were 0.01 IU/ml dalteparin, 0.02 IU/ml heparin, 25 KIU/ml aprotinin, and 12 mM arginine. The efficiency of any anticoagulant on intrinsic thrombin generation should be measured for each individual patient. Abbreviations IIa, thrombin; δA, increase in absorbance; APTT, activated partial thromboplastin time; CRT, coagulation reaction time (at 37°C in water-bath; F-wells, polystyrole microtiter plates with flat bottom; IC50, inhibitory concentration 50%; INCA, intrinsic coagulation activity assay; IU, international units; KIU, kallikrein inhibiting unis; LMWH, low molecular weight heparin; mA, milli-absorbance units; PSL, pathromtin SL®; RT, room temperature (23°C; U-wells, polystyrole microtiter plates with round bottom.

  13. [Penicillium-inhibiting yeasts].

    Science.gov (United States)

    Benítez Ahrendts, M R; Carrillo, L

    2004-01-01

    The objective of this work was to establish the in vitro and in vivo inhibition of post-harvest pathogenic moulds by yeasts in order to make a biocontrol product. Post-harvest pathogenic moulds Penicillium digitatum, P. italicum, P. ulaiense, Phyllosticta sp., Galactomyces geotrichum and yeasts belonging to genera Brettanomyces, Candida, Cryptococcus, Kloeckera, Pichia, Rhodotorula were isolated from citrus fruits. Some yeasts strains were also isolated from other sources. The yeasts were identified by their macro and micro-morphology and physiological tests. The in vitro and in vivo activities against P. digitatum or P. ulaiense were different. Candida cantarellii and one strain of Pichia subpelliculosa produced a significant reduction of the lesion area caused by the pathogenic moulds P. digitatum and P. ulaiense, and could be used in a biocontrol product formulation.

  14. [Urease inhibition by polymer analogs of substrate and thiophosphamides].

    Science.gov (United States)

    Metelitsa, D I; Tarun, E I; Puchkaev, A V; Losev, Iu P

    2001-01-01

    Inhibition of soybean urease by polymeric substrate analogues, urea and thiourea polydisulfides (PDSU and PDSTU, respectively), or three thiophosphoric acid amides (TPAA), tri-(N-3-hydroxyphenyl)thiophosphamide (1), tri-(N-4,4'-aminodiphenyl)thiophosphamide, and di-oxy-(N-alpha-piridyl)thiophosphamide (3) was studied in aqueous solutions at various pH values. The inhibitory effects of all these substances were reversible and competitive with the lowest inhibition constant Ki 2.8 microM for TPAA-1 at pH 3.85. Above and below this pH value, Ki increased reaching 24 [mu]M at pH 7.2. All test substances inhibited urease comparably with known inhibitors such as thiols (cysteamine, etc.) and hydroxamic acid derivatives, but were less efficient than phosphorodiamidates. Structural features of possible urease inhibitors of higher efficiency were proposed.

  15. In vitro inhibition of pathogenic Verticillium dahliae , causal agent of ...

    African Journals Online (AJOL)

    Most of the single spore isolates and TGZ-SC-4 were found to have higher MyI efficiency than that of the rest. The results indicate that the Trichoderma isolates in this study have initial modes of action of biological control to protect potato crop against V. dahlia. Keywords: Trichoderma, potato wilt disease, growth inhibition, ...

  16. [Inhibition of soybean urease by polycarbonyl compounds].

    Science.gov (United States)

    Tarun, E I; Rubinov, D B; Metelitsa, D I

    2005-01-01

    Competitive inhibition of soybean urease was studied at 36 degrees C in aqueous solution (pH 4.95) in the presence of polycarbonyl compounds (PCCs): oxalyldihydrazide (ODH), its polydisulfide (poly(DSODH)), three cyclic beta-triketones (CTKs), and seven cyclic PCC species of differing structure. The inhibition constants of ureolysis (Ki) varied in the range 8.5-3800 microM depending on the structure of organic chelators for the nickel atom in urease. It was shown that pH variation within the range from 3.85 to 7.40 exerted a strong effect on the values of Ki] of three CTKs and hydroxyurea, which was used as a reference: pH dependences of lgK(i) were linear in all cases and displayed a break at pH 6.0-6.5. The most effective inhibitor of ureolysis was poly(DSODH), which contained approximately 28 carbonyl groups in the polymer molecule. The role of such factors as the number of carbonyl groups per PCC molecule, mutual arrangement, and reaction medium pH in the efficiency of the process of urease inhibition is discussed.

  17. Corrosion Inhibition of Cast Iron in Arabian Gulf Seawater by Two Different Ionic Liquids.

    Science.gov (United States)

    Sherif, El-Sayed M; Abdo, Hany S; Abedin, Sherif Zein El

    2015-06-26

    In this paper we report on the corrosion inhibition of cast iron in Arabian Gulf seawater by two different ionic liquids namely, 1-ethyl-3-methylimidazolium chloride ([EMIm]Cl) and 1-butyl-1-methylpyrrolidinium chloride ([Py 1,4 ]Cl). The inhibiting influence of the employed ionic liquids was investigated by weight loss, open circuit potential electrochemical impedance spectroscopy, and cyclic potentiodynamic polarization. The results show the corrosion inhibition impact of the employed ionic liquids (ILs). Compared with [Py 1,4 ]Cl, [EMIm]Cl shows a higher inhibition efficiency at a short immersion time, for the examined ILs concentrations. However, [Py 1,4 ]Cl exhibits a higher efficiency upon increasing the immersion time indicating the persistence of the inhibiting influence. The corrosion inhibition of the employed ionic liquids is attributed to the adsorption of the cations of the ionic liquids onto the surface of cast iron forming a corrosion barrier.

  18. Corrosion Inhibition of Cast Iron in Arabian Gulf Seawater by Two Different Ionic Liquids

    Directory of Open Access Journals (Sweden)

    El-Sayed M. Sherif

    2015-06-01

    Full Text Available In this paper we report on the corrosion inhibition of cast iron in Arabian Gulf seawater by two different ionic liquids namely, 1-ethyl-3-methylimidazolium chloride ([EMIm]Cl and 1-butyl-1-methylpyrrolidinium chloride ([Py1,4]Cl. The inhibiting influence of the employed ionic liquids was investigated by weight loss, open circuit potential electrochemical impedance spectroscopy, and cyclic potentiodynamic polarization. The results show the corrosion inhibition impact of the employed ionic liquids (ILs. Compared with [Py1,4]Cl, [EMIm]Cl shows a higher inhibition efficiency at a short immersion time, for the examined ILs concentrations. However, [Py1,4]Cl exhibits a higher efficiency upon increasing the immersion time indicating the persistence of the inhibiting influence. The corrosion inhibition of the employed ionic liquids is attributed to the adsorption of the cations of the ionic liquids onto the surface of cast iron forming a corrosion barrier.

  19. Dicumarol inhibition of NADPH:quinone oxidoreductase induces growth inhibition of pancreatic cancer via a superoxide-mediated mechanism.

    Science.gov (United States)

    Cullen, Joseph J; Hinkhouse, Marilyn M; Grady, Matthew; Gaut, Andrew W; Liu, Jingru; Zhang, Yu Ping; Weydert, Christine J Darby; Domann, Frederick E; Oberley, Larry W

    2003-09-01

    NADPH:quinone oxidoreductase (NQO(1)), a homodimeric, ubiquitous, flavoprotein, catalyzes the two-electron reduction of quinones to hydroquinones. This reaction prevents the one-electron reduction of quinones by cytochrome P450 reductase and other flavoproteins that would result in oxidative cycling with generation of superoxide (O(2)(.-)). NQO(1) gene regulation may be up-regulated in some tumors to accommodate the needs of rapidly metabolizing cells to regenerate NAD(+). We hypothesized that pancreatic cancer cells would exhibit high levels of this enzyme, and inhibiting it would suppress the malignant phenotype. Reverse transcription-PCR, Western blots, and activity assays demonstrated that NQO(1) was up-regulated in the pancreatic cancer cell lines tested but present in very low amounts in the normal human pancreas. To determine whether inhibition of NQO(1) would alter the malignant phenotype, MIA PaCa-2 pancreatic cancer cells were treated with a selective inhibitor of NQO(1), dicumarol. Dicumarol increased intracellular production of O(2)(.-), as measured by hydroethidine staining, and inhibited cell growth. Both of these effects were blunted with infection of an adenoviral vector containing the cDNA for manganese superoxide dismutase. Dicumarol also inhibited cell growth, plating efficiency, and growth in soft agar. We conclude that inhibition of NQO(1) increases intracellular O(2)(.-) production and inhibits the in vitro malignant phenotype of pancreatic cancer. These mechanisms suggest that altering the intracellular redox environment of pancreatic cancer cells may inhibit growth and delineate a potential strategy directed against pancreatic cancer.

  20. CORROSION INHIBITION OF CARBON STEEL XC70 IN H2SO4 ...

    African Journals Online (AJOL)

    2012-12-31

    Dec 31, 2012 ... In this work, we studied the efficiency of corrosion inhibition of carbon steel XC70 in H2SO4. 0.5 M aqueous solution using ... Keywords: Corrosion, carbon steel XC70, Inhibition, ferrocene derivative, Adsorption. 1. INTRODUCTION ... oxide film which may be present on the surface. The electrode was then ...

  1. Improved Inhibition of Telomerase by Short Twisted Intercalating Nucleic Acids under Molecular Crowding Conditions

    DEFF Research Database (Denmark)

    Agarwal, Tani; Pradhan, Devranjan; Géci, Imrich

    2012-01-01

    Human telomeric DNA has the ability to fold into a 4-stranded G-quadruplex structure. Several G-quadruplex ligands are known to stabilize the structure and thereby inhibit telomerase activity. Such ligands have demonstrated efficient telomerase inhibition in dilute conditions, but under molecular...

  2. Reconsidering energy efficiency

    International Nuclear Information System (INIS)

    Goldoni, Giovanni

    2007-01-01

    Energy and environmental policies are reconsidering energy efficiency. In a perfect market, rational and well informed consumers reach economic efficiency which, at the given prices of energy and capital, corresponds to physical efficiency. In the real world, market failures and cognitive frictions distort the consumers from perfectly rational and informed choices. Green incentive schemes aim at balancing market failures and directing consumers toward more efficient goods and services. The problem is to fine tune the incentive schemes [it

  3. Energy efficiency; Efficacite energetique

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-06-15

    This road-map proposes by the Group Total aims to inform the public on the energy efficiency. It presents the energy efficiency and intensity around the world with a particular focus on Europe, the energy efficiency in industry and Total commitment. (A.L.B.)

  4. Efficiency of Brownian Motors

    OpenAIRE

    Parrondo, J. M. R.; Blanco, J. M.; Cao, F. J.; Brito, R.

    1998-01-01

    The efficiency of different types of Brownian motors is calculated analytically and numerically. We find that motors based on flashing ratchets present a,low efficiency and an unavoidable entropy production. On the other hand, a certain class of motors based on adiabatically changing potentials, named reversible ratchets, exhibit a higher efficiency and the entropy production can be arbitrarily reduced.

  5. Inhibition of multiplication of herpes simplex virus by caffeic acid.

    Science.gov (United States)

    Ikeda, Keiko; Tsujimoto, Kazuko; Uozaki, Misao; Nishide, Mitsunori; Suzuki, Yukiko; Koyama, A Hajime; Yamasaki, Hisashi

    2011-10-01

    Hot water extracts of coffee grinds and commercial instant coffee solutions have been shown to exhibit marked antiviral and virucidal activities against herpes simplex virus type 1 (HSV-1). Specifically, it has been shown that caffeine and N-methyl-pyridinium formate inhibit the multiplication of HSV-1 in HEp-2 cells. The present study examined the virological properties and the antiviral activity of caffeic acid against HSV-1. Caffeic acid inhibited the multiplication of HSV-1 in vitro, while chlorogenic acid, a caffeic acid ester with quinic acid, did not. These reagents did not have a direct virucidal effect. The one-step growth curve of HSV-1 showed that the addition of caffeic acid at 8 h post infection (h p.i.) did not significantly affect the formation of progeny viruses. An analysis of the influence of the time of caffeic acid addition, revealed that addition at an early time post infection remarkably inhibited the formation of progeny infectious virus in the infected cells, but its addition after 6 h p.i. (i.e., the time of the completion of viral genome replication) did not efficiently inhibit this process. These results indicate that caffeic acid inhibits HSV-1 multiplication mainly before the completion of viral DNA replication, but not thereafter. Although caffeic acid showed some cytotoxicity by prolonged incubation, the observed antiviral activity is likely not the secondary result of the cytotoxic effect of the reagent, because the inhibition of the virus multiplication was observed before appearance of the notable cytotoxicity.

  6. Highly reflective reasoners show no signs of belief inhibition.

    Science.gov (United States)

    Svedholm-Häkkinen, Annika M

    2015-01-01

    The processes underlying individual differences in reasoning performance are not entirely understood. What do people who do well on reasoning tasks where beliefs and logic conflict do differently from other people? Because abundant evidence shows that even poorer reasoners detect these conflicts, it has been suggested that individual differences in reasoning performance arise from inhibition failures later in the reasoning process. The present paper argues that a minority of highly skilled reasoners may deviate from this general reasoning process from an early stage. Two studies investigated signs of belief inhibition using a lexical access paradigm (Study 1) and a negative priming paradigm (Study 2). Study 1 showed that while other people exhibited signs of belief inhibition following a belief-logic conflict, people with the highest disposition for cognitive reflection did not. In Study 2, this finding was replicated and similar results were also obtained when comparing groups with higher and lower general cognitive ability. Two possible explanations are discussed. The reasoners with a highly reflective cognitive style or high general cognitive ability may have engaged and inhibited belief processing but if so, they may have been exceptionally efficient at recovering from it, wherefore no belief inhibition effects were found. An alternative account is that these reasoners started Type 2 processing directly, without first engaging in and then inhibiting belief-based processing. Under either explanation, the results indicate that individual differences in reasoning may partly arise from differences that occur early in the reasoning process. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Inhibition of the acid corrosion of aluminium by some derivatives of thiosemicarbazone

    Directory of Open Access Journals (Sweden)

    P.C. Okafor

    2004-12-01

    Full Text Available The inhibition of corrosion of aluminium in HCl solution by some derivatives of thiosemicarbazones has been studied using weight loss and hydrogen evolution techniques. The thiosemicarbazone derivatives used are 2-acetyl pyridine-(4-phenylthiosemicarbazone (PTSC, 2-acetyl pyridine-(4-phenyl-iso-methylthiosemicarbazone (PIMTSC and 2-acetyl pyridine-(4-phenyl-iso-ethylthiosemicarbazone (PIETSC. The inhibition efficiency depended on the compounds concentration until at very low concentration studied where they reversed their functions and became accelerators. Kinetic treatment of the results gave a first order type of mechanism. The results reported in this paper elucidate the effects of inhibitor concentration, temperature and the molecular structure on the inhibition efficiency.

  8. Selective inhibition of distracting input.

    Science.gov (United States)

    Noonan, MaryAnn P; Crittenden, Ben M; Jensen, Ole; Stokes, Mark G

    2017-10-16

    We review a series of studies exploring distractor suppression. It is often assumed that preparatory distractor suppression is controlled via top-down mechanisms of attention akin to those that prepare brain areas for target enhancement. Here, we consider two alternative mechanisms: secondary inhibition and expectation suppression within a predictive coding framework. We draw on behavioural studies, evidence from neuroimaging and some animal studies. We conclude that there is very limited evidence for selective top-down control of preparatory inhibition. By contrast, we argue that distractor suppression often relies secondary inhibition of non-target items (relatively non-selective inhibition) and on statistical regularities of the environment, learned through direct experience. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  9. [Concepts of inhibition in psychiatry].

    Science.gov (United States)

    Auroux, Y; Bourrat, M M; Brun, J P

    1978-01-01

    Following a historical approach, the authors first describe the original development of the concept of inhibition in neurophysiology and then analyze the subsequent adaptations made in psychiatry around such concept including those of: -- Pavlov, Hull, Watson and the behaviorists, -- Freud and the Freudian School, -- clinicians and psychopharmacologists. The concept of inhibition has thus various meanings in psychiatry. Although some unity is achieved on the semiological level, this aspect cannot explain the extent of the process.

  10. Revisiting energy efficiency fundamentals

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Lombard, L.; Velazquez, D. [Grupo de Termotecnia, Escuela Superior de Ingenieros, Universidad de Sevilla, Camino de los Descubrimientos s/n, 41092 Seville (Spain); Ortiz, J. [Building Research Establishment (BRE), Garston, Watford, WD25 9XX (United Kingdom)

    2013-05-15

    Energy efficiency is a central target for energy policy and a keystone to mitigate climate change and to achieve a sustainable development. Although great efforts have been carried out during the last four decades to investigate the issue, focusing into measuring energy efficiency, understanding its trends and impacts on energy consumption and to design effective energy efficiency policies, many energy efficiency-related concepts, some methodological problems for the construction of energy efficiency indicators (EEI) and even some of the energy efficiency potential gains are often ignored or misunderstood, causing no little confusion and controversy not only for laymen but even for specialists. This paper aims to revisit, analyse and discuss some efficiency fundamental topics that could improve understanding and critical judgement of efficiency stakeholders and that could help in avoiding unfounded judgements and misleading statements. Firstly, we address the problem of measuring energy efficiency both in qualitative and quantitative terms. Secondly, main methodological problems standing in the way of the construction of EEI are discussed, and a sequence of actions is proposed to tackle them in an ordered fashion. Finally, two key topics are discussed in detail: the links between energy efficiency and energy savings, and the border between energy efficiency improvement and renewable sources promotion.

  11. Cyanide does more to inhibit heme enzymes, than merely serving as an active-site ligand

    Energy Technology Data Exchange (ETDEWEB)

    Parashar, Abhinav [Center for Biomedical Research, VIT University, Vellore, Tamil Nadu, 632014 India (India); Venkatachalam, Avanthika [REDOx Lab, PSG Institute of Advanced Studies, Avinashi Road, Peelamedu, Coimbatore, Tamil Nadu, 641004 (India); Gideon, Daniel Andrew [Center for Biomedical Research, VIT University, Vellore, Tamil Nadu, 632014 India (India); Manoj, Kelath Murali, E-mail: satyamjayatu@yahoo.com [REDOx Lab, PSG Institute of Advanced Studies, Avinashi Road, Peelamedu, Coimbatore, Tamil Nadu, 641004 (India)

    2014-12-12

    Highlights: • Cyanide (CN) is a well-studied toxic principle, known to inhibit heme-enzymes. • Inhibition is supposed to result from CN binding at the active site as a ligand. • Diverse heme enzymes’ CN inhibition profiles challenge prevailing mechanism. • Poor binding efficiency of CN at low enzyme concentrations and ligand pressures. • CN-based diffusible radicals cause ‘non-productive electron transfers’ (inhibition). - Abstract: The toxicity of cyanide is hitherto attributed to its ability to bind to heme proteins’ active site and thereby inhibit their activity. It is shown herein that the long-held interpretation is inadequate to explain several observations in heme-enzyme reaction systems. Generation of cyanide-based diffusible radicals in heme-enzyme reaction milieu could shunt electron transfers (by non-active site processes), and thus be detrimental to the efficiency of oxidative outcomes.

  12. Inhibition of dioscin on Saprolegnia in vitro.

    Science.gov (United States)

    Liu, Lei; Shen, Yu-Feng; Liu, Guang-Lu; Ling, Fei; Liu, Xin-Yang; Hu, Kun; Yang, Xian-Le; Wang, Gao-Xue

    2015-12-01

    As one of the most serious pathogens in the freshwater aquatic environment, Saprolegnia can induce a high mortality rate during the fish egg incubation period. This study investigated the anti-Saprolegnia activity of a total of 108 plants on Saprolegnia parasitica in vitro and Dioscorea collettii was selected for further studies. By loading on an open silica gel column and eluting with petroleum ether-ethyl acetate-methanol, dioscin (C45H72O16) was isolated from D. collettii. Saprolegnia parasitica growth was inhibited significantly when dioscin concentration was more than 2.0 mg L(-1). When compared with formalin and hydrogen peroxide, dioscin showed a higher inhibitory effect. As potential inhibition mechanisms, dioscin could cause the S. parasitica mycelium morphologic damage, dense folds, or disheveled protuberances observed by field emission scanning electron microscopy and the influx of Propidium iodide. The structural changes in the treated mycelium were indicative of an efficient anti-Saprolegnia activity of dioscin. The oxidative stress results showed that dioscin also accumulated reactive oxygen species excessively and increased total antioxidant and superoxide dismutase activity. These situations could render S. parasitica more vulnerable to oxidative damage. Additionally, when dioscin concentration was less than 2.0 mg L(-1), the survival rate of embryos was more than 70%. Therefore, the use of dioscin could be a viable way of preventing and controlling saprolegniasis. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Corrosion Inhibition Study of Al-Cu-Ni Alloy in Simulated Sea-Water ...

    African Journals Online (AJOL)

    Akorede

    inhibitor in the environment resulted in the formation a protective layer on the metal surface thereby reducing the corrosion rate. This finding is in conformity with that reported by Ihebrodike et al (2010) and Nnanna et al, (2010). B. Effect of Inhibitor Concentration on Inhibition Efficiency. The inhibitor efficiency increases with ...

  14. More efficient together

    DEFF Research Database (Denmark)

    Zhang, Tian

    2015-01-01

    approach to make photosynthesis more efficient is to build hybrid systems that combine inorganic and microbial components to produce specific chemicals. Such hybrid bioinorganic systems lead to improved efficiency and specificity and do not require processed vegetable biomass. They thus prevent harmful......The solar-to-biomass conversion efficiency of natural photosynthesis is between 2.9 and 4.3% for most crops (1, 2). Improving the efficiency of photosynthesis could help increase the appeal of biologically derived fuels and chemicals in comparison with traditional petrochemical processes. One...

  15. Reactor design for minimizing product inhibition during enzymatic lignocellulose hydrolysis: II. Quantification of inhibition and suitability of membrane reactors.

    Science.gov (United States)

    Andrić, Pavle; Meyer, Anne S; Jensen, Peter A; Dam-Johansen, Kim

    2010-01-01

    Product inhibition of cellulolytic enzymes affects the efficiency of the biocatalytic conversion of lignocellulosic biomass to ethanol and other valuable products. New strategies that focus on reactor designs encompassing product removal, notably glucose removal, during enzymatic cellulose conversion are required for alleviation of glucose product inhibition. Supported by numerous calculations this review assesses the quantitative aspects of glucose product inhibition on enzyme-catalyzed cellulose degradation rates. The significance of glucose product inhibition on dimensioning of different ideal reactor types, i.e. batch, continuous stirred, and plug-flow, is illustrated quantitatively by modeling different extents of cellulose conversion at different reaction conditions. The main operational challenges of membrane reactors for lignocellulose conversion are highlighted. Key membrane reactor features, including system set-up, dilution rate, glucose output profile, and the problem of cellobiose are examined to illustrate the quantitative significance of the glucose product inhibition and the total glucose concentration on the cellulolytic conversion rate. Comprehensive overviews of the available literature data for glucose removal by membranes and for cellulose enzyme stability in membrane reactors are given. The treatise clearly shows that membrane reactors allowing continuous, complete, glucose removal during enzymatic cellulose hydrolysis, can provide for both higher cellulose hydrolysis rates and higher enzyme usage efficiency (kg(product)/kg(enzyme)). Current membrane reactor designs are however not feasible for large scale operations. The report emphasizes that the industrial realization of cellulosic ethanol requires more focus on the operational feasibility within the different hydrolysis reactor designs, notably for membrane reactors, to achieve efficient enzyme-catalyzed cellulose degradation. (c) 2010 Elsevier Inc. All rights reserved.

  16. Homo economicus belief inhibits trust.

    Directory of Open Access Journals (Sweden)

    Ziqiang Xin

    Full Text Available As a foundational concept in economics, the homo economicus assumption regards humans as rational and self-interested actors. In contrast, trust requires individuals to believe partners' benevolence and unselfishness. Thus, the homo economicus belief may inhibit trust. The present three experiments demonstrated that the direct exposure to homo economicus belief can weaken trust. And economic situations like profit calculation can also activate individuals' homo economicus belief and inhibit their trust. It seems that people's increasing homo economicus belief may serve as one cause of the worldwide decline of trust.

  17. Homo economicus belief inhibits trust.

    Science.gov (United States)

    Xin, Ziqiang; Liu, Guofang

    2013-01-01

    As a foundational concept in economics, the homo economicus assumption regards humans as rational and self-interested actors. In contrast, trust requires individuals to believe partners' benevolence and unselfishness. Thus, the homo economicus belief may inhibit trust. The present three experiments demonstrated that the direct exposure to homo economicus belief can weaken trust. And economic situations like profit calculation can also activate individuals' homo economicus belief and inhibit their trust. It seems that people's increasing homo economicus belief may serve as one cause of the worldwide decline of trust.

  18. Nitrogen use efficiency (NUE)

    NARCIS (Netherlands)

    Oenema, O.

    2015-01-01

    There is a need for communications about resource use efficiency and for measures to increase the use efficiency of nutrients in relation to food production. This holds especially for nitrogen. Nitrogen (N) is essential for life and a main nutrient element. It is needed in relatively large

  19. Energy Efficient TCP

    NARCIS (Netherlands)

    Donckers, L.; Smit, Gerardus Johannes Maria; Havinga, Paul J.M.; Smit, L.T.

    This paper describes the design of an energy-efficient transport protocol for mobile wireless communication. First we describe the metrics used to measure the energy efficiency of transport protocols. We identify several problem areas that prevent TCP/IP from reaching high levels of energy

  20. Energy Efficiency Collaboratives

    Energy Technology Data Exchange (ETDEWEB)

    Li, Michael [US Department of Energy, Washington, DC (United States); Bryson, Joe [US Environmental Protection Agency, Washington, DC (United States)

    2015-09-01

    Collaboratives for energy efficiency have a long and successful history and are currently used, in some form, in more than half of the states. Historically, many state utility commissions have used some form of collaborative group process to resolve complex issues that emerge during a rate proceeding. Rather than debate the issues through the formality of a commission proceeding, disagreeing parties are sent to discuss issues in a less-formal setting and bring back resolutions to the commission. Energy efficiency collaboratives take this concept and apply it specifically to energy efficiency programs—often in anticipation of future issues as opposed to reacting to a present disagreement. Energy efficiency collaboratives can operate long term and can address the full suite of issues associated with designing, implementing, and improving energy efficiency programs. Collaboratives can be useful to gather stakeholder input on changing program budgets and program changes in response to performance or market shifts, as well as to provide continuity while regulators come and go, identify additional energy efficiency opportunities and innovations, assess the role of energy efficiency in new regulatory contexts, and draw on lessons learned and best practices from a diverse group. Details about specific collaboratives in the United States are in the appendix to this guide. Collectively, they demonstrate the value of collaborative stakeholder processes in producing successful energy efficiency programs.

  1. Hyper-accurate ribosomes inhibit growth.

    Science.gov (United States)

    Ruusala, T; Andersson, D; Ehrenberg, M; Kurland, C G

    1984-11-01

    We have compared both in vivo and in vitro translation by ribosomes from wild-type bacteria with those from streptomycin-resistant (SmR), streptomycin-dependent (SmD) and streptomycin-pseudo-dependent (SmP) mutants. The three mutant bacteria translate more accurately and more slowly in the absence of streptomycin (Sm) than do wild-type bacteria. In particular, the SmP bacteria grow at roughly half the rate of the wild-type in the absence of Sm. The antibiotic stimulates both the growth rate and the translation rate of SmP bacteria by approximately 2-fold, but it simultaneously increases the nonsense suppression rate quite dramatically. Kinetic experiments in vitro show that the greater accuracy and slower translation rates of mutant ribosomes compared with wild-type ribosomes are associated with much more rigorous proofreading activities of SmR, SmD and SmP ribosomes. Sm reduces the proofreading flows of the mutant ribosomes and stimulates their elongation rates. The data suggest that these excessively accurate ribosomes are kinetically less efficient than wild-type ribosomes, and that this inhibits mutant growth rates. The stimulation of the growth of the mutants by Sm results from the enhanced translational efficiency due to the loss of proofreading, which more than offsets the loss of accuracy caused by the antibiotic.

  2. Evaluation of the inhibitive effect of some plant extracts on the acid corrosion of mild steel

    International Nuclear Information System (INIS)

    Oguzie, Emeka E.

    2008-01-01

    Corrosion inhibition of mild steel in 2 M HCl and 1 M H 2 SO 4 by extracts of selected plants was investigated using a gasometric technique at temperatures of 30 and 60 deg. C. The studied plants materials include leaf extracts Occimum viridis (OV), Telferia occidentalis (TO), Azadirachta indica (AI) and Hibiscus sabdariffa (HS) as well as extracts from the seeds of Garcinia kola (GK). The results indicate that all the extracts inhibited the corrosion process in both acid media by virtue of adsorption and inhibition efficiency improved with concentration. Synergistic effects increased the inhibition efficiency in the presence of halide additives. Inhibition mechanisms were deduced from the temperature dependence of the inhibition efficiency as well as from assessment of kinetic and activation parameters that govern the processes. Comparative analysis of the inhibitor adsorption behaviour in 2 M HCl and 1 M H 2 SO 4 as well as the effects of temperature and halide additives suggest that both protonated and molecular species could be responsible for the inhibiting action of the extracts

  3. Evaluation of the inhibitive effect of some plant extracts on the acid corrosion of mild steel

    Energy Technology Data Exchange (ETDEWEB)

    Oguzie, Emeka E. [Electrochemistry and Materials Science Research Laboratory, Department of Chemistry, Federal University of Technology, PMB 1526, Owerri (Nigeria)], E-mail: oguziemeka@yahoo.com

    2008-11-15

    Corrosion inhibition of mild steel in 2 M HCl and 1 M H{sub 2}SO{sub 4} by extracts of selected plants was investigated using a gasometric technique at temperatures of 30 and 60 deg. C. The studied plants materials include leaf extracts Occimum viridis (OV), Telferia occidentalis (TO), Azadirachta indica (AI) and Hibiscus sabdariffa (HS) as well as extracts from the seeds of Garcinia kola (GK). The results indicate that all the extracts inhibited the corrosion process in both acid media by virtue of adsorption and inhibition efficiency improved with concentration. Synergistic effects increased the inhibition efficiency in the presence of halide additives. Inhibition mechanisms were deduced from the temperature dependence of the inhibition efficiency as well as from assessment of kinetic and activation parameters that govern the processes. Comparative analysis of the inhibitor adsorption behaviour in 2 M HCl and 1 M H{sub 2}SO{sub 4} as well as the effects of temperature and halide additives suggest that both protonated and molecular species could be responsible for the inhibiting action of the extracts.

  4. Testing of Biologically Inhibiting Surface

    DEFF Research Database (Denmark)

    Bill Madsen, Thomas; Larsen, Erup

    2003-01-01

    The main purpose of this course is to examine a newly developed biologically inhibiting material with regards to galvanic corrosion and electrochemical properties. More in detail, the concern was how the material would react when exposed to cleaning agents, here under CIP cleaning (Cleaning...

  5. Experimental and molecular dynamics study on the inhibition performance of some nitrogen containing compounds for iron corrosion

    International Nuclear Information System (INIS)

    Khaled, K.F.

    2010-01-01

    A molecular dynamics study for the adsorption of three benzimidazole derivatives and their inhibition characteristics was studied using chemical (weight loss) and electrochemical measurements (potentiodynamic polarization and electrochemical impedance spectroscopy, EIS). Electrochemical measurements results revealed that the inhibition efficiencies increased with the concentration of inhibitors. Results obtained from weight loss, dc polarization and ac impedance measurements are in reasonably good agreement and show increased inhibitor efficiency with increasing inhibitor concentration. The molecular dynamics calculations showed that the higher the binding energy between the inhibitor and metal surface, the higher the inhibition efficiency. Also, the higher the adsorption energy, the higher the inhibition efficiency. The molecular dynamics study revealed that the benzimidazole ring as well as the side chain are the active sites in these inhibitors and they can absorb on Fe surface by donating electrons to Fe d-orbital.

  6. The Efficient Windows Collaborative

    Energy Technology Data Exchange (ETDEWEB)

    Petermann, Nils

    2006-03-31

    The Efficient Windows Collaborative (EWC) is a coalition of manufacturers, component suppliers, government agencies, research institutions, and others who partner to expand the market for energy efficient window products. Funded through a cooperative agreement with the U.S. Department of Energy, the EWC provides education, communication and outreach in order to transform the residential window market to 70% energy efficient products by 2005. Implementation of the EWC is managed by the Alliance to Save Energy, with support from the University of Minnesota and Lawrence Berkeley National Laboratory.

  7. Learning efficient correlated equilibria

    KAUST Repository

    Borowski, Holly P.

    2014-12-15

    The majority of distributed learning literature focuses on convergence to Nash equilibria. Correlated equilibria, on the other hand, can often characterize more efficient collective behavior than even the best Nash equilibrium. However, there are no existing distributed learning algorithms that converge to specific correlated equilibria. In this paper, we provide one such algorithm which guarantees that the agents\\' collective joint strategy will constitute an efficient correlated equilibrium with high probability. The key to attaining efficient correlated behavior through distributed learning involves incorporating a common random signal into the learning environment.

  8. Protein C inhibitor acts as a procoagulant by inhibiting the thrombomodulin-induced activation of protein C in human plasma

    NARCIS (Netherlands)

    Elisen, M. G.; von dem Borne, P. A.; Bouma, B. N.; Meijers, J. C.

    1998-01-01

    Protein C inhibitor (PCI), which was originally identified as an inhibitor of activated protein C, also efficiently inhibits coagulation factors such as factor Xa and thrombin. Recently it was found, using purified proteins, that the anticoagulant thrombin-thrombomodulin complex was also inhibited

  9. Transport Energy Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    Transport is the sector with the highest final energy consumption and, without any significant policy changes, is forecast to remain so. In 2008, the IEA published 25 energy efficiency recommendations, among which four are for the transport sector. The recommendations focus on road transport and include policies on improving tyre energy efficiency, fuel economy standards for both light-duty vehicles and heavy-duty vehicles, and eco-driving. Implementation of the recommendations has been weaker in the transport sector than others. This paper updates the progress that has been made in implementing the transport energy efficiency recommendations in IEA countries since March 2009. Many countries have in the last year moved from 'planning to implement' to 'implementation underway', but none have fully implemented all transport energy efficiency recommendations. The IEA calls therefore for full and immediate implementation of the recommendations.

  10. Energy Efficient Cryogenics

    Science.gov (United States)

    Meneghelli, Barry J.; Notardonato, William; Fesmire, James E.

    2016-01-01

    The Cryogenics Test Laboratory, NASA Kennedy Space Center, works to provide practical solutions to low-temperature problems while focusing on long-term technology targets for the energy-efficient use of cryogenics on Earth and in space.

  11. Educated for Efficiency

    DEFF Research Database (Denmark)

    Amore, Mario Daniele; Bennedsen, Morten; Larsen, Birthe

    We study the effect of CEO education on a firm’s energy efficiency. Using a unique dataset of Danish firms, we document that firms led by more educated CEOs exhibit greater energy efficiency. We establish causality by employing exogenous CEO hospitalization episodes: the hospitalization of highly......-educated CEOs induces a drop in a firm’s energy efficiency, whereas the hospitalization of low-education CEOs does not have any significant effect. Disentangling the effect of educational length from that of the field of study, we find that the greater energy efficiency is mostly driven by the cumulated years...... of CEO education rather than by having obtained business or technical-related degrees....

  12. Energy efficiency and behaviour

    DEFF Research Database (Denmark)

    Carstensen, Trine Agervig; Kunnasvirta, Annika; Kiviluoto, Katariina

    The purpose of Work Package 5 Deliverable 5.1., “Case study reports on energy efficiency and behaviour” is to present examples of behavioral interventions to promote energy efficiency in cities. The case studies were collected in January – June 2014, and they represent behavioural interventions...... from different sectors of energy efficiency from the following PLEEC partner countries: Denmark, Sweden, Finland, the UK, the Netherlands, Estonia, Bulgaria and Spain. Each case is presented shortly with key details of budget, target group, and methods as well as a short assessment of main success...... factors. The main addressees of D5.1. are city officials, NGO representatives, private sector actors and any other relevant actors who plan and realize behavioural energy efficiency interventions in European cities. The WP5 team will also further apply results from D5.1. with a more general model on how...

  13. Efficient incremental relaying

    KAUST Repository

    Fareed, Muhammad Mehboob

    2013-07-01

    We propose a novel relaying scheme which improves the spectral efficiency of cooperative diversity systems by utilizing limited feedback from destination. Our scheme capitalizes on the fact that relaying is only required when direct transmission suffers deep fading. We calculate the packet error rate for the proposed efficient incremental relaying scheme with both amplify and forward and decode and forward relaying. Numerical results are also presented to verify their analytical counterparts. © 2013 IEEE.

  14. Centrifugal Contactor Efficiency Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Mincher, Bruce Jay [Idaho National Lab. (INL), Idaho Falls, ID (United States); Tillotson, Richard Dean [Idaho National Lab. (INL), Idaho Falls, ID (United States); Grimes, Travis Shane [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2017-01-01

    The contactor efficiency of a 2-cm acrylic centrifugal contactor, fabricated by ANL using 3D printer technology was measured by comparing a contactor test run to 5-min batch contacts. The aqueous phase was ~ 3 ppm depleted uranium in 3 M HNO3, and the organic phase was 1 M DAAP/dodecane. Sampling during the contactor run showed that equilibrium was achieved within < 3 minutes. The contactor efficiency at equilibrium was 95% to 100 %, depending on flowrate.

  15. Physicochemical studies of glucose, gellan gum, and hydroxypropyl cellulose--inhibition of cast iron corrosion.

    Science.gov (United States)

    Rajeswari, Velayutham; Kesavan, Devarayan; Gopiraman, Mayakrishnan; Viswanathamurthi, Periasamy

    2013-06-05

    Glucose, gellan gum, and hydroxypropyl cellulose were studied against the acid corrosion of cast iron by means of weight loss, potentiodynamic polarization, and AC impedance spectroscopy techniques. The inhibition efficiency was found to increase with increasing concentration of the inhibitors. The effect of immersion time and temperature were also studied. The addition of potassium iodide to the corrosion-inhibition system showed both antagonism and synergism toward inhibition efficiency. Polarization studies revealed the mixed-type inhibiting nature of the carbohydrates. The adsorption of inhibitors on the cast iron surface obeys Langmuir adsorption isotherm model, both in presence and absence of KI. Physical interaction between the inhibitor molecules and the iron surface was suggested by the thermochemical parameters, rather than chemical interaction. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. A Comparative Study of the Corrosion Inhibitive Properties of Pyrimidine Derivatives for Mild Steel

    Directory of Open Access Journals (Sweden)

    P. Sathya

    2009-01-01

    Full Text Available The influence of pyrimidine derivatives on the corrosion inhibition of mild steel in 1 M H2SO4 was studied using weight loss and electrochemical techniques. These compounds act as good corrosion inhibitors even at low concentration and the inhibition efficiency increased with the increase in inhibition concentration. The corrosion rates have been determined at various temperatures (303-333K by weight loss measurements. The Rt values obtained from EIS method increased with increase in inhibitor concentration. The potentiostatic polarization results clearly revealed that the inhibitors behave as a mixed type but slightly anodic in nature. The adsorption process was found to obey the Langmuir adsorption isotherm. The synergistic effect of halide ion on the inhibition efficiency increase with increase concentration.

  17. Corrosion Inhibition Studies of Mild Steel in Acid Medium Using Musa Acuminata Fruit Peel Extract

    Directory of Open Access Journals (Sweden)

    N. Gunavathy

    2012-01-01

    Full Text Available The inhibition effect of unripe fruit peel extract of Musa acuminata (Cultivar variety – Nendran (MNP on corrosion of mild steel in 1 N HCl has been investigated by weight loss and electrochemical impedance spectroscopy (EIS with various concentrations of the extract. The effect of temperature on the corrosion inhibition of mild steel in the temperature range of 30°C – 80°C was carried out. The results indicate that MNP extract act as an effective inhibitor in the acid environment and is of mixed type inhibitor having efficiency as high as 96% at 2% inhibitor concentration. The inhibition efficiency of MNP extract increases with the increase of concentration but decreases with the increase in temperature. The inhibitor achieves its inhibition by physical adsorption of nutrients of the peel extract on the surface of the mild steel. The experimental data revealed that the adsorption occurred according to the Langmuir and Temkin adsorption isotherm.

  18. Efficient Windows Collaborative

    Energy Technology Data Exchange (ETDEWEB)

    Nils Petermann

    2010-02-28

    The project goals covered both the residential and commercial windows markets and involved a range of audiences such as window manufacturers, builders, homeowners, design professionals, utilities, and public agencies. Essential goals included: (1) Creation of 'Master Toolkits' of information that integrate diverse tools, rating systems, and incentive programs, customized for key audiences such as window manufacturers, design professionals, and utility programs. (2) Delivery of education and outreach programs to multiple audiences through conference presentations, publication of articles for builders and other industry professionals, and targeted dissemination of efficient window curricula to professionals and students. (3) Design and implementation of mechanisms to encourage and track sales of more efficient products through the existing Window Products Database as an incentive for manufacturers to improve products and participate in programs such as NFRC and ENERGY STAR. (4) Development of utility incentive programs to promote more efficient residential and commercial windows. Partnership with regional and local entities on the development of programs and customized information to move the market toward the highest performing products. An overarching project goal was to ensure that different audiences adopt and use the developed information, design and promotion tools and thus increase the market penetration of energy efficient fenestration products. In particular, a crucial success criterion was to move gas and electric utilities to increase the promotion of energy efficient windows through demand side management programs as an important step toward increasing the market share of energy efficient windows.

  19. Corrosion inhibition of alpha brass by 1-phenyl-3-methyl-pyrazol-5 ...

    African Journals Online (AJOL)

    Corrosion inhibition of alpha brass by 1-phenyl-3-methyl-pyrazol-5-one in acidic media at different temperatures. ... Global Journal of Engineering Research ... The corrosion inhibition efficiency (C.I.E.) of the alpha brass was 99.83%, using the condition of 3.0M HNO3 for the uninhibited experiment and 0.03M HPMP for the ...

  20. Inhibition of the corrosion of mild steel in hydrochloric acid by isatin ...

    African Journals Online (AJOL)

    The inhibition of corrosion of mild steel in hydrochloric acid by isatin glycine (ING) and isatin (IN) at 30-60 oC and concentrations of 0.0001 M to 0.0005 M was studied via weight loss method. At the highest inhibitor concentration studied ING exhibited inhibition efficiency of 87% while IN exhibited 84% at 60 oC. A chemical ...

  1. [Inhibition by chitosan of productive infection of T-series bacteriophages in the Escherichia coli culture].

    Science.gov (United States)

    Kochkina, Z M; Pospeshny, G; Chirkov, S N

    1995-01-01

    The possibility of the use of chitosan aminopolysaccharide (poly-D-glucosamine) and its two salts--acetate and hydrochloride--to prevent phase infection of the Escherichia coli culture, strain B1, was studied. It was shown that chitosan inhibited productive infection caused by the bacteriophages T2 and T7, the efficiency of inhibition of both bacteriophages depending directly on the final concentration of chitosan in a medium. Neither chitosan nor its salts significantly prevented the growth of the bacterial culture.

  2. Supernovae Discovery Efficiency

    Science.gov (United States)

    John, Colin

    2018-01-01

    Abstract:We present supernovae (SN) search efficiency measurements for recent Hubble Space Telescope (HST) surveys. Efficiency is a key component to any search, and is important parameter as a correction factor for SN rates. To achieve an accurate value for efficiency, many supernovae need to be discoverable in surveys. This cannot be achieved from real SN only, due to their scarcity, so fake SN are planted. These fake supernovae—with a goal of realism in mind—yield an understanding of efficiency based on position related to other celestial objects, and brightness. To improve realism, we built a more accurate model of supernovae using a point-spread function. The next improvement to realism is planting these objects close to galaxies and of various parameters of brightness, magnitude, local galactic brightness and redshift. Once these are planted, a very accurate SN is visible and discoverable by the searcher. It is very important to find factors that affect this discovery efficiency. Exploring the factors that effect detection yields a more accurate correction factor. Further inquires into efficiency give us a better understanding of image processing, searching techniques and survey strategies, and result in an overall higher likelihood to find these events in future surveys with Hubble, James Webb, and WFIRST telescopes. After efficiency is discovered and refined with many unique surveys, it factors into measurements of SN rates versus redshift. By comparing SN rates vs redshift against the star formation rate we can test models to determine how long star systems take from the point of inception to explosion (delay time distribution). This delay time distribution is compared to SN progenitors models to get an accurate idea of what these stars were like before their deaths.

  3. The effect of Zn2+ ion in promoting inhibitive property of phenolphthalein

    Directory of Open Access Journals (Sweden)

    J. Jeyasundari

    2010-01-01

    Full Text Available The inhibition efficiency of phenolphthalein in controlling corrosion of carbon steel immersed in well water has been evaluatedby mass loss method both in absence and presence of zinc ion. A synergistic effect exists between phenolphthalein (PNand Zn2+. The inhibition efficiency (IE of the PN – Zn2+ system decreases with increase in immersion period. Addition ofN-Cetyl-N, N, N-Trimethylammlonium bromide (CTAB sodium dodecyl sulphate (SDS, sodium sulphite (Na2SO3 doesnot change the excellent inhibition efficiency of the PN-Zn2+ system. Polarization study suggests that the Pn-Zn2+ systemfunctions as a mixed inhibitor system. AC impedance spectra reveal the presence of a protective film on the metal surface.FTIR spectra indicate that the protective film consists of Fe2+-PN complex and Zn(OH2.

  4. On inhibition of dental erosion.

    Science.gov (United States)

    Rölla, Gunnar; Jonski, Grazyna; Saxegaard, Erik

    2013-11-01

    To examine the erosion-inhibiting effect of different concentrations of hydrofluoric acid. Thirty-six human molars were individually treated with 10 ml of 0.1 M citric acid for 30 min (Etch 1), acid was collected and stored until analysis. The teeth were randomly divided into six groups and then individually treated with 10 ml of one of six dilutions (from 0.1-1%) of hydrofluoric acid. The teeth were then again treated with citric acid (Etch 2). The individual acid samples from Etch 1 and 2 were analyzed for calcium by flame atomic absorption spectroscopy and difference in calcium loss was calculated. The highest erosion inhibiting effect was obtained in groups with the highest concentrations of hydrofluoric acid, where the pH was lowest, below pKa of 3.17, thus the hydrofluoric acids being mainly in an undissociated state. Diluted hydrofluoric acid is present in aqueous solution of SnF2 and TiF4 (which are known to inhibit dental erosion): SnF2 + 3H2O = Sn(OH)2 + 2HF + H2O and TiF4 + 5H2O = Ti(OH)4 + 4HF + H2O. It is also known that pure, diluted hydrofluoric acid can inhibit dental erosion. Teeth treated with hydrofluoric acid are covered by a layer of CaF2-like mineral. This mineral is acid resistant at pH acid resistant mineral, initiated by tooth enamel treatment with hydrofluoric acid. Hydrofluoric acid is different in having fluoride as a conjugated base, which provides this acid with unique properties.

  5. Corrosion Inhibition of Carbon Steel in HCl Solution by Some Plant Extracts

    Directory of Open Access Journals (Sweden)

    Ambrish Singh

    2012-01-01

    Full Text Available The strict environmental legislations and increasing ecological awareness among scientists have led to the development of “green” alternatives to mitigate corrosion. In the present work, literature on green corrosion inhibitors has been reviewed, and the salient features of our work on green corrosion inhibitors have been highlighted. Among the studied leaves, extract Andrographis paniculata showed better inhibition performance (98% than the other leaves extract. Strychnos nuxvomica showed better inhibition (98% than the other seed extracts. Moringa oleifera is reflected as a good corrosion inhibitor of mild steel in 1 M HCl with 98% inhibition efficiency among the studied fruits extract. Bacopa monnieri showed its maximum inhibition performance to be 95% at 600 ppm among the investigated stem extracts. All the reported plant extracts were found to inhibit the corrosion of mild steel in acid media.

  6. Reciprocal inhibition in Parkinson's disease.

    Science.gov (United States)

    Tsai, C H; Chen, R S; Lu, C S

    1997-01-01

    We studied the inhibition of median H-reflex by conditioning stimuli on the radial nerve in 14 normal controls, 6 patients with unilateral and 1 patient with predominantly left-sided Parkinson's disease. In normal controls, the electrophysiological studies were performed on their right hands, yet both hands were examined in patient group. In the controls, we identified three inhibitory phases, with maximal inhibition at conditioning-test intervals of 0 ms (41.66 +/- 4.73%), 20 ms (45.19 +/- 4.33%), and 100 ms (44.55 +/- 6.84%), respectively. In the less- or a- symptomatic side of the patient group, the inhibitory patterns are similar to those of the controls. However, in the symptomatic arms, loss of inhibition, or even mild potentiation, was observed in the third inhibitory phase. When the symptomatic and asymptomatic sides of patients were compared, in contrast to the striking phenomenon found between symptomatic side and the controls, no difference was observed in the third phase. The current results imply that, although no obvious rigidity can be detected on the asymptomatic sides, subtle functional corruption may have occurred within the contralateral basal ganglia in patients with unilateral Parkinson's disease. The remarkable change of the third phase on the symptomatic sides of patients suggests the perturbation of the polysynaptic long latency reflex pathway may somehow play a role in the rigidity pathogenesis.

  7. Aβ association inhibition by transferrin.

    Science.gov (United States)

    Raditsis, Annie V; Milojevic, Julijana; Melacini, Giuseppe

    2013-07-16

    The iron-transport glycoprotein transferrin has recently been shown to serve as a potent inhibitor of Aβ self-association. Although this novel, to our knowledge, inhibitory function of transferrin is of potential therapeutic interest for the treatment of Alzheimer's disease, the underlying mechanism is still not fully understood. Although it has been shown that the Fe(III) sequestration by transferrin reduces oxidative damage and Aβ aggregation, it is not clear whether transferrin is also able to inhibit Aβ self-association through direct binding of Aβ. Here, using saturation transfer and off-resonance relaxation NMR spectroscopy, we show that transferrin inhibits Aβ aggregation also by preferentially binding Aβ oligomers and outcompeting Aβ monomers that would otherwise cause the growth of the Aβ oligomers into larger assemblies. This inhibitory mechanism is different from the iron-sequestration model, but it is qualitatively similar to a mechanism previously proposed for the inhibition of Aβ self-association by another plasma and cerebrospinal fluid protein, i.e., human serum albumin. These results suggest that Aβ monomer competition through direct Aβ oligomer binding might be a general strategy adopted by proteins in plasma and cerebrospinal fluid to prevent Aβ aggregation. Copyright © 2013 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  8. Serotonin, inhibition, and negative mood.

    Directory of Open Access Journals (Sweden)

    Peter Dayan

    2008-02-01

    Full Text Available Pavlovian predictions of future aversive outcomes lead to behavioral inhibition, suppression, and withdrawal. There is considerable evidence for the involvement of serotonin in both the learning of these predictions and the inhibitory consequences that ensue, although less for a causal relationship between the two. In the context of a highly simplified model of chains of affectively charged thoughts, we interpret the combined effects of serotonin in terms of pruning a tree of possible decisions, (i.e., eliminating those choices that have low or negative expected outcomes. We show how a drop in behavioral inhibition, putatively resulting from an experimentally or psychiatrically influenced drop in serotonin, could result in unexpectedly large negative prediction errors and a significant aversive shift in reinforcement statistics. We suggest an interpretation of this finding that helps dissolve the apparent contradiction between the fact that inhibition of serotonin reuptake is the first-line treatment of depression, although serotonin itself is most strongly linked with aversive rather than appetitive outcomes and predictions.

  9. Multi-directional program efficiency

    DEFF Research Database (Denmark)

    Asmild, Mette; Balezentis, Tomas; Hougaard, Jens Leth

    2016-01-01

    approach is used to estimate efficiency. This enables a consideration of input-specific efficiencies. The study shows clear differences between the efficiency scores on the different inputs as well as between the farm types of crop, livestock and mixed farms respectively. We furthermore find that crop...... farms have the highest program efficiency, but the lowest managerial efficiency and that the mixed farms have the lowest program efficiency (yet not the highest managerial efficiency)....

  10. Span efficiency in hawkmoths.

    Science.gov (United States)

    Henningsson, Per; Bomphrey, Richard J

    2013-07-06

    Flight in animals is the result of aerodynamic forces generated as flight muscles drive the wings through air. Aerial performance is therefore limited by the efficiency with which momentum is imparted to the air, a property that can be measured using modern techniques. We measured the induced flow fields around six hawkmoth species flying tethered in a wind tunnel to assess span efficiency, ei, and from these measurements, determined the morphological and kinematic characters that predict efficient flight. The species were selected to represent a range in wingspan from 40 to 110 mm (2.75 times) and in mass from 0.2 to 1.5 g (7.5 times) but they were similar in their overall shape and their ecology. From high spatio-temporal resolution quantitative wake images, we extracted time-resolved downwash distributions behind the hawkmoths, calculating instantaneous values of ei throughout the wingbeat cycle as well as multi-wingbeat averages. Span efficiency correlated positively with normalized lift and negatively with advance ratio. Average span efficiencies for the moths ranged from 0.31 to 0.60 showing that the standard generic value of 0.83 used in previous studies of animal flight is not a suitable approximation of aerodynamic performance in insects.

  11. National energy efficiency programme

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    This paper focusses on energy conservation and specifically on energy efficiency which includes efficiency in the production, delivery and utilisation of energy as part of the total energy system of the economy. A National Energy Efficiency Programme is being launched in the Eighth Plan that will take into account both macro level and policy and planning considerations as well as micro level responses for different category of users in the industry, agriculture, transport and domestic sectors. The need for such a National Energy Efficiency Programme after making an assessment of existing energy conservation activities in the country is discussed. The broad framework and contents of the National Energy Efficiency Programme have been outlined and the Eighth Plan targets for energy conservation and their break-up have been given. These targets, as per the Eighth Plan document are 5000 MW in electricity installed capacity and 6 million tonnes of petroleum products by the terminal year of the Eighth Plan. The issues that need to be examined for each sector for achieving the above targets for energy conservation in the Eighth Plan are discussed briefly. They are: (a) policy and planning, (b) implementation arrangements which include the institutional setup and selective legislation, (c) technological requirements, and (d) resource requirements which include human resources and financial resources. (author)

  12. Energy Efficiency Center - Overview

    International Nuclear Information System (INIS)

    Obryk, E.

    2000-01-01

    Full text: The Energy Efficiency Center (EEC) activities have been concentrated on Energy Efficiency Network (SEGE), education and training of energy auditors. EEC has started studies related to renewable fuels (bio fuel, wastes) and other topics related to environment protection. EEC has continued close collaboration with Institute for Energy Technology, Kjeller, Norway. It has been organized and conducted Seminar and Workshop on ''How to Reduce Energy and Water Cost in Higher Education Buildings'' for general and technical managers of the higher education institutions. This Seminar was proceeded by the working meeting on energy efficiency strategy in higher education at the Ministry of National Education. EEC has worked out proposal for activities of Cracow Regional Agency for Energy Efficiency and Environment and has made offer to provide services for this Agency in the field of training, education and consulting. The vast knowledge and experiences in the field of energy audits have been used by the members of EEC in lecturing at energy auditors courses authorized by the National Energy Efficiency Agency (KAPE). Altogether 20 lectures have been delivered. (author)

  13. Inhibition effect on lipid oxidation of irradiated pork by adding hawthorn flavonoid extract

    International Nuclear Information System (INIS)

    Wang Xiaoming; Liu Chao; Cao Lei; Li Kexi

    2011-01-01

    The antioxidant activity of hawthorn flavonoid extract and its inhibition effect on irradiated pork lipid oxidant were investigated. The results showed that hawthorn flavonoids had efficient scavenging effect on DPPH free radicals (DPPH ·), and the scavenging rate reached 56% while 2 ml of 0.035 mg/ml hawthorn flavonoid extract was added. Hawthorn flavonoid extract can inhibition the lipid oxidation of irradiated pork effectively and it showed a stronger inhibition ability while the hawthorn flavonoid extract were used together with Vc. It is concluded that can decrease the lipid oxidation of pork, hawthorn flavonoid extract is a remarkable natural antioxidant. (authors)

  14. Inhibition Effect of Miconazole Nitrate on the Corrosion of Mild Steel in Hydrochloric Acid Medium

    Directory of Open Access Journals (Sweden)

    J. Ishwara Bhat

    2011-01-01

    Full Text Available The corrosion inhibition of mild steel by miconazole nitrate, an antifungal drug has been investigated using potentiodynamic polarization, electrochemical impedance spectroscopy technique, and weight loss methods. The experimental results suggested miconazole nitrate is a good corrosion inhibitor for mild steel in 1 M hydrochloric acid medium. The inhibition efficiency increased with increase in inhibitor concentration. The thermodynamic parameters were determined and discussed. The inhibition was assumed to occur via adsorption of the inhibitor molecule on the surface of mild steel following Langmuir adsorption isotherm.

  15. Corrosion inhibition of mild steel in hydrochloric acid solution by some double Schiff bases

    Energy Technology Data Exchange (ETDEWEB)

    Soltani, N. [Payame Noor University (PNU), Shahin Shahr Branch, Isfahan (Iran, Islamic Republic of)], E-mail: N.Soltani@kashanu.ac.ir; Behpour, M.; Ghoreishi, S.M.; Naeimi, H. [Department of Chemistry, Faculty of Science, University of Kashan, Kashan (Iran, Islamic Republic of)

    2010-04-15

    The inhibition effect of four double Schiff bases on the corrosion of mild steel in 2 M HCl has been studied by polarization, electrochemical impedance spectroscopy (EIS) and weight loss measurements. The inhibitors were adsorbed on the steel surface according to the Langmuir adsorption isotherm model. From the adsorption isotherm, some thermodynamic data for the adsorption process were calculated and discussed. Kinetic parameters activation such as E{sub a}, {delta}H*, {delta}S* were evaluated from the effect of temperature on corrosion and inhibition processes. Quantum chemical calculations have been performed and several quantum chemical indices were calculated and correlated with the corresponding inhibition efficiencies.

  16. Hydrodynamic Effect on the Inhibition for the Flow Accelerated Corrosion of an Elbow

    International Nuclear Information System (INIS)

    Zeng, L.; Zhang, G. A.; Guo, X. P.

    2017-01-01

    The inhibition effect of thioureido imidazoline inhibitor (TAI) for flow accelerated corrosion (FAC) at different locations for an X65 carbon steel elbow was studied by array electrode and computational fluid dynamics (CFD) simulations. The distribution of the inhibition efficiency measured by electrochemical impedance spectroscopy (EIS) is in good accordance with the distribution of the hydrodynamic parameters at the elbow. The inhibition efficiencies at the outer wall are higher than those at the inner wall meaning that the lower inhibition efficiency is associated with a higher flow velocity, shear stress, and turbulent kinetic energy at the inner wall of the elbow, as well as secondary flow at the elbow rather than the mass transport of inhibitor molecules. Compared to the static condition, the inhibition efficiency of TAI for FAC was relatively low. It is also due to a drastic turbulence flow and high wall shear stress during the FAC test, which prevents the adsorption of inhibitor and/or damages the adsorbed inhibitor film.

  17. A DFT study of pyrazine derivatives and their Fe complexes in corrosion inhibition process

    Science.gov (United States)

    Behzadi, Hadi; Roonasi, Payman; Momeni, Mohammad Jafar; Manzetti, Sergio; Esrafili, Mehdi D.; Obot, I. B.; Yousefvand, Mostafa; Morteza Mousavi-Khoshdel, S.

    2015-04-01

    The DFT/B3LYP calculations were applied to investigate the relationship between electronic properties and corrosion inhibition efficiency of three pyrazine derivatives, 2-methylpyrazine (MP), 2-aminopyrazine (AP) and 2-amino-5-bromopyrazine (ABP). To take into account the solution acidity in experimental conditions, all possible mono-protonated forms, that is protonation at N1, N4 and NH2 sites, as well as the non-protonated form were considered. The molecular orbital analysis showed a good correlation between EHOMO, ELUMO and ΔE (EHOMO - ELUMO) with inhibition efficiency of the three pyrazine derivatives. Four types of interactions between iron and pyrazine molecules, i.e. Fe-π, Fe-N1, Fe-N4 and Fe-NH2 were included in the calculations. As a new approach to this system, inhibition mechanism of the three pyrazine molecules has been discussed in detail based on these four types of interactions. It was found that all four interactions are energetically important. The flat pyrazine ring was substantially deformed followed by a Fe-π interaction. The calculated binding energy of ABP in all forms was found to be higher than two other pyrazines, which is consistent with experimentally observed highest corrosion inhibition efficiency. The lack of Fe-NH2 interaction for MP molecule seems to be the reason for its lower corrosion inhibition efficiency.

  18. Native and tabun-inhibited cholinesterase interactions with oximes

    International Nuclear Information System (INIS)

    Kovarik, Z.; Katalinic, M.; Sinko, G.

    2009-01-01

    The phosphorylation of the serine hydroxyl group in the active site of acetylcholinesterase (AChE) inactivates this essential enzyme in neurotransmission. Its related enzyme butyrylcholinesterase (BChE) also interacts with organophosphorus compounds (OP) scavenging anti-cholinesterase agents and protects synaptic AChE from inhibition. Oximes are reactivators of AChE phosphorylated by OP including insecticides and nerve agents. The effectiveness of oxime-assisted reactivation is primarily attributed to the nucleophilic displacement rate of organophosphate, but efficiency varies with the structure of the bound organophosphate, the structure of the oxime as well as rates of several other cholinesterase's reactions. Besides reactivating cholinesterases, oximes also reversibly inhibit both cholinesterases and protect them from phosphorylation by OP. We tested oximes varying in the type of ring (pyridinium and/or imidazolium), the length and type of the linker between rings, and in the position of the oxime group on the ring to find more effective oximes to reactivate tabun-inhibited human erythrocyte AChE and plasma BChE. Herein we bring an overview of in vitro interactions of native and tabun-inhibited AChE and BChE with oximes together with conformational analysis of the oximes relating molecular properties to their reactivation potency.(author)

  19. Rho kinase inhibitors block melanoma cell migration and inhibit metastasis.

    Science.gov (United States)

    Sadok, Amine; McCarthy, Afshan; Caldwell, John; Collins, Ian; Garrett, Michelle D; Yeo, Maggie; Hooper, Steven; Sahai, Erik; Kuemper, Sandra; Mardakheh, Faraz K; Marshall, Christopher J

    2015-06-01

    There is an urgent need to identify new therapeutic opportunities for metastatic melanoma. Fragment-based screening has led to the discovery of orally available, ATP-competitive AKT kinase inhibitors, AT13148 and CCT129254. These compounds also inhibit the Rho-kinases ROCK 1 and ROCK 2 and we show they potently inhibit ROCK activity in melanoma cells in culture and in vivo. Treatment of melanoma cells with CCT129254 or AT13148 dramatically reduces cell invasion, impairing both "amoeboid-like" and mesenchymal-like modes of invasion in culture. Intravital imaging shows that CCT129254 or AT13148 treatment reduces the motility of melanoma cells in vivo. CCT129254 inhibits melanoma metastasis when administered 2 days after orthotopic intradermal injection of the cells, or when treatment starts after metastases have arisen. Mechanistically, our data suggest that inhibition of ROCK reduces the ability of melanoma cells to efficiently colonize the lungs. These results suggest that these novel inhibitors of ROCK may be beneficial in the treatment of metastasis. ©2015 American Association for Cancer Research.

  20. Efficiency of scanning automatons

    International Nuclear Information System (INIS)

    Shkundenkov, V.N.

    1977-01-01

    Investigated are the methods for improving the efficiency of the picture processing system based on an automatic scanner. Discussed are two types of such a system. In the first case the system contains both automatic and semi-automatic scanners. In the second case the system includes only the automatic scanners with the man-to-computer dialog facilities. For analyzing the role of the automatic scanner and the role of the operator in the processing system use is made of the processing system balance equation. It is proved that the picture processing system should be designed in two steps. The first step should, by all means, insure high efficiency in processing but the high capacity is not obligatory. The second step is aimed at higher capacity along with high efficiency. So, such a two-step designing makes it possible to solve the problem of higher capacity and lesser cost of picture processing

  1. EFFICIENCY OF LOGISTIC SYSTEMS

    Directory of Open Access Journals (Sweden)

    S. M Salum

    2006-01-01

    Full Text Available Main missions of production and distributive logistics are defined in the paper. The paper gives the concept of logistic distribution channel. The possibility of its selection is analyzed, and that is a significant reserve to improve efficiency of logistic processes.The paper considers efficiency of logistic and transport-technological systems on the basis of the relationship of aggregate gross revenue and aggregate costs of an enterprise.The paper cites a concept of economic criterion of efficiency describing the whole logistic chain, that is from the moment of primary raw materials output to consumption of products at all stages of production and transportation of primary raw materials, semi-finished and finished products.

  2. Measuring efficiency in logistics

    Directory of Open Access Journals (Sweden)

    Milan Milovan Andrejić

    2013-06-01

    Full Text Available Dynamic market and environmental changes greatly affect operating of logistics systems. Logistics systems have to realize their activities and processes in an efficient way. The main objective of this paper is to analyze different aspects of efficiency measurement in logistics and to propose appropriate models of measurement. Measuring efficiency in logistics is a complex process that requires consideration of all subsystems, processes and activities as well as the impact of various financial, operational, environmental, quality and other factors. The proposed models have a basis in the Data Envelopment Analysis method. They could help managers in decision making and corrective actions processes. The tests and results of the model show the importance of input and output variables selection.

  3. Efficient Learning Design

    DEFF Research Database (Denmark)

    Godsk, Mikkel

    engaging educators in the design process and developing teaching and learning, it is a shift in educational practice that potentially requires a stakeholder analysis and ultimately a business model for the deployment. What is most important is to balance the institutional, educator, and student......This paper presents the current approach to implementing educational technology with learning design at the Faculty of Science and Technology, Aarhus University, by introducing the concept of ‘efficient learning design’. The underlying hypothesis is that implementing learning design is more than...... perspectives and to consider all these in conjunction in order to obtain a sustainable, efficient learning design. The approach to deploying learning design in terms of the concept of efficient learning design, the catalyst for educational development, i.e. the learning design model and how it is being used...

  4. Danish Energy Efficiency Policy

    DEFF Research Database (Denmark)

    Togeby, Mikael; Larsen, Anders; Dyhr-Mikkelsen, Kirsten

    2009-01-01

    Ten groups of policy instruments for promoting energy efficiency are actively used in Denmark. Among these are the EU instruments such as the CO2 emissions trading scheme and labelling of appliances, labelling of all buildings, combined with national instruments such as high taxes especially...... of the entire Danish energy efficiency policy portfolio must be carried out before end 2008 and put forward for discussion among governing parties no later than February 2009. A consortium comprising Ea Energy Analyses, Niras, the Department of Society and Globalisation (Roskilde University) and 4-Fact...... was assigned with this task. The evaluation aimed to answer the crucial questions: Is the overall design of the portfolio of instruments appropriate? Does the impact of the instruments justify the costs, so that we reach the national goals in a cost efficient way? Will the current instrument portfolio be able...

  5. Efficiency in Microfinance Cooperatives

    Directory of Open Access Journals (Sweden)

    HARTARSKA, Valentina

    2012-12-01

    Full Text Available In recognition of cooperatives’ contribution to the socio-economic well-being of their participants, the United Nations has declared 2012 as the International Year of Cooperatives. Microfinance cooperatives make a large part of the microfinance industry. We study efficiency of microfinance cooperatives and provide estimates of the optimal size of such organizations. We employ the classical efficiency analysis consisting of estimating a system of equations and identify the optimal size of microfinance cooperatives in terms of their number of clients (outreach efficiency, as well as dollar value of lending and deposits (sustainability. We find that microfinance cooperatives have increasing returns to scale which means that the vast majority can lower cost if they become larger. We calculate that the optimal size is around $100 million in lending and half of that in deposits. We find less robust estimates in terms of reaching many clients with a range from 40,000 to 180,000 borrowers.

  6. Efficient convolutional sparse coding

    Energy Technology Data Exchange (ETDEWEB)

    Wohlberg, Brendt

    2017-06-20

    Computationally efficient algorithms may be applied for fast dictionary learning solving the convolutional sparse coding problem in the Fourier domain. More specifically, efficient convolutional sparse coding may be derived within an alternating direction method of multipliers (ADMM) framework that utilizes fast Fourier transforms (FFT) to solve the main linear system in the frequency domain. Such algorithms may enable a significant reduction in computational cost over conventional approaches by implementing a linear solver for the most critical and computationally expensive component of the conventional iterative algorithm. The theoretical computational cost of the algorithm may be reduced from O(M.sup.3N) to O(MN log N), where N is the dimensionality of the data and M is the number of elements in the dictionary. This significant improvement in efficiency may greatly increase the range of problems that can practically be addressed via convolutional sparse representations.

  7. Energy efficiency; Energieffektivisering

    Energy Technology Data Exchange (ETDEWEB)

    2009-06-15

    The Low Energy Panel will halve the consumption in buildings. The Panel has proposed a halving of consumption in the construction within 2040 and 20 percent reduction in the consumption in the industry within 2020. The Panel consider it as possible to gradually reduce consumption in buildings from the current level of 80 TWh with 10 TWh in 2020, 25 TWh in 2030 and 40 TWh in 2040. According the committee one such halving can be reached by significant efforts relating to energy efficiency, by greater rehabilitations, energy efficiency in consisting building stock and stricter requirements for new construction. For the industry field the Panel recommend a political goal to be set at least 20 percent reduction in specific energy consumption in the industry and primary industry beyond general technological development by the end of 2020. This is equivalent to approximately 17 TWh based on current level of activity. The Panel believes that a 5 percent reduction should be achieved by the end of 2012 by carrying out simple measures. The Low Energy Panel has since March 2009 considered possibilities to strengthen the authorities' work with energy efficiency in Norway. The wide complex panel adds up proposals for a comprehensive approach for increased energy efficiency in particular in the building- and industry field. The Panel has looked into the potential for energy efficiency, barriers for energy efficiency, assessment of strengths and weaknesses in the existing policy instruments and members of the Panel's recommendations. In addition the report contains a review of theoretical principles for effects of instruments together with an extensive background. One of the committee members have chosen to take special notes on the main recommendations in the report. (AG)

  8. Efficient use of energy

    CERN Document Server

    Dryden, IGC

    2013-01-01

    The Efficient Use of Energy, Second Edition is a compendium of papers discussing the efficiency with which energy is used in industry. The collection covers relevant topics in energy handling and describes the more important features of plant and equipment. The book is organized into six parts. Part I presents the various methods of heat production. The second part discusses the use of heat in industry and includes topics in furnace design, industrial heating, boiler plants, and water treatment. Part III deals with the production of mechanical and electrical energy. It tackles the principles o

  9. efficience technico-economique

    African Journals Online (AJOL)

    USER

    Les indices d'inefficience coût varient de 1 à 2,86 pour l'oignon et de 1 à 1,77 pour la pomme de terre. ..... Ci ûi. Ci*. Cj*. Xi. Xj. Coût Moyen. Coût Minimale. Figure 3 : Principe de l'efficience coût selon l'approche FFSC. Cost efficiency principle according to SFCF approach. ... différentes quantités des divers engrais utilisés.

  10. Financing Energy Efficient Homes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    Existing buildings require over 40% of the world's total final energy consumption, and account for 24% of world CO2 emissions (IEA, 2006). Much of this consumption could be avoided through improved efficiency of building energy systems (IEA, 2006) using current, commercially-viable technology. In most cases, these technologies make economic sense on a life-cycle cost analysis (IEA, 2006b). Moreover, to the extent that they reduce dependence on risk-prone fossil energy sources, energy efficient technologies also address concerns of energy security.

  11. Institutions, Equilibria and Efficiency

    DEFF Research Database (Denmark)

    Competition and efficiency is at the core of economic theory. This volume collects papers of leading scholars, which extend the conventional general equilibrium model in important ways. Efficiency and price regulation are studied when markets are incomplete and existence of equilibria...... membership are evaluated. Core equivalence is shown for bargaining economies. The theory of risk aversion is extended and the relation between risk taking and wealth is experimentally investigated. Other topics include: determinacy in OLG with cash-in-advance constraints, income distribution and democracy...... in OLG, learning in OLG and in games, optimal pricing of derivative securities, the impact of heterogeneity...

  12. Dimensions of energy efficiency

    International Nuclear Information System (INIS)

    Ramani, K.V.

    1992-01-01

    In this address the author describes three dimensions of energy efficiency in order of increasing costs: conservation, resource and technology substitution, and changes in economic structure. He emphasizes the importance of economic rather than environmental rationales for energy efficiency improvements in developing countries. These countries do not place high priority on the problems of global climate change. Opportunities for new technologies may exist in resource transfer, new fuels and, possibly, small reactors. More research on economic and social impacts of technologies with greater sensitivity to user preferences is needed

  13. Fuzzy efficiency without convexity

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Balezentis, Tomas

    2014-01-01

    In this paper we develop a fuzzy version of the crisp Free Disposal Hull (FDH) method for measuring technical efficiency for samples of similar production units. The FDH-method is basically Data Envelopment Analysis (DEA) without the underlying assumption of convexity of the technology set. Our...... approach builds directly upon the definition of Farrell's indexes of technical efficiency used in crisp FDH. Therefore we do not require the use of fuzzy programming techniques but only utilize ranking probabilities of intervals as well as a related definition of dominance between pairs of intervals. We...

  14. Energy Efficiency Financing for Low- and Moderate-Income Households: Current State of the Market, Issues, and Opportunities

    Energy Technology Data Exchange (ETDEWEB)

    None

    2017-08-01

    Although the need is great, many LMI households may not be able to afford efficiency improvements or may be inhibited from adopting efficiency for other reasons. Decision-makers across the country are currently exploring the challenges and potential solutions to ramping up adoption of efficiency in LMI households, including the use of financing.

  15. ENERGY EFFICIENT LAUNDRY PROCESS

    Energy Technology Data Exchange (ETDEWEB)

    Tim Richter

    2005-04-01

    With the rising cost of energy and increased concerns for pollution and greenhouse gas emissions from power generation, increased focus is being put on energy efficiency. This study looks at several approaches to reducing energy consumption in clothes care appliances by considering the appliances and laundry chemistry as a system, rather than individually.

  16. The efficiency of freedom

    DEFF Research Database (Denmark)

    Madsen, Christian Østergaard; Kræmmergaard, Pernille

    2015-01-01

    The Danish e-government strategy aims to increase the efficiency of public sector administration by making e-government channels mandatory for citizens by 2015. Although Danish citizens have adopted e-government channels to interact with public authorities, many also keep using traditional channels...

  17. Robust efficient video fingerprinting

    Science.gov (United States)

    Puri, Manika; Lubin, Jeffrey

    2009-02-01

    We have developed a video fingerprinting system with robustness and efficiency as the primary and secondary design criteria. In extensive testing, the system has shown robustness to cropping, letter-boxing, sub-titling, blur, drastic compression, frame rate changes, size changes and color changes, as well as to the geometric distortions often associated with camcorder capture in cinema settings. Efficiency is afforded by a novel two-stage detection process in which a fast matching process first computes a number of likely candidates, which are then passed to a second slower process that computes the overall best match with minimal false alarm probability. One key component of the algorithm is a maximally stable volume computation - a three-dimensional generalization of maximally stable extremal regions - that provides a content-centric coordinate system for subsequent hash function computation, independent of any affine transformation or extensive cropping. Other key features include an efficient bin-based polling strategy for initial candidate selection, and a final SIFT feature-based computation for final verification. We describe the algorithm and its performance, and then discuss additional modifications that can provide further improvement to efficiency and accuracy.

  18. ERP=Efficiency

    Science.gov (United States)

    Violino, Bob

    2008-01-01

    This article discusses the enterprise resource planning (ERP) system. Deploying an ERP system is one of the most extensive--and expensive--IT projects a college or university can undertake. The potential benefits of ERP are significant: a more smoothly running operation with efficiencies in virtually every area of administration, from automated…

  19. Web anonymization efficiency study

    Science.gov (United States)

    Sochor, Tomas

    2017-11-01

    The analysis of TOR, JonDo and CyberGhost efficiency (measured the as latency increase and transmission speed decrease) is presented in the paper. Results showed that all tools have relatively favorable latency increase (no more than 60% RTT increase). The transmission speed increase was much more significant (more than 60%), and even more for JonDo (above 90%).

  20. An efficiency correction model

    NARCIS (Netherlands)

    Francke, M.K.; de Vos, A.F.

    2009-01-01

    We analyze a dataset containing costs and outputs of 67 American local exchange carriers in a period of 11 years. This data has been used to judge the efficiency of BT and KPN using static stochastic frontier models. We show that these models are dynamically misspecified. As an alternative we

  1. Microeconomics : Equilibrium and Efficiency

    NARCIS (Netherlands)

    Ten Raa, T.

    2013-01-01

    Microeconomics: Equilibrium and Efficiency teaches how to apply microeconomic theory in an innovative, intuitive and concise way. Using real-world, empirical examples, this book not only covers the building blocks of the subject, but helps gain a broad understanding of microeconomic theory and

  2. Combining Expert Advice Efficiently

    NARCIS (Netherlands)

    W.M. Koolen-Wijkstra (Wouter); S. de Rooij (Steven)

    2008-01-01

    htmlabstractWe show how models for prediction with expert advice can be defined concisely and clearly using hidden Markov models (HMMs); standard HMM algorithms can then be used to efficiently calculate, among other things, how the expert predictions should be weighted according to the model. We

  3. Corporate efficiency in Europe

    Czech Academy of Sciences Publication Activity Database

    Hanousek, Jan; Kočenda, E.; Shamshur, Anastasiya

    2015-01-01

    Roč. 32, June (2015), s. 24-40 ISSN 0929-1199 R&D Projects: GA ČR(CZ) GA15-15927S Institutional support: PRVOUK-P23 Keywords : efficiency * ownership structure * firms Subject RIV: AH - Economics Impact factor: 1.286, year: 2015

  4. Higher Efficiency HVAC Motors

    Energy Technology Data Exchange (ETDEWEB)

    Flynn, Charles Joseph [QM Power, Inc., Kansas City, MO (United States)

    2018-02-13

    The objective of this project was to design and build a cost competitive, more efficient heating, ventilation, and air conditioning (HVAC) motor than what is currently available on the market. Though different potential motor architectures among QMP’s primary technology platforms were investigated and evaluated, including through the building of numerous prototypes, the project ultimately focused on scaling up QM Power, Inc.’s (QMP) Q-Sync permanent magnet synchronous motors from available sub-fractional horsepower (HP) sizes for commercial refrigeration fan applications to larger fractional horsepower sizes appropriate for HVAC applications, and to add multi-speed functionality. The more specific goal became the research, design, development, and testing of a prototype 1/2 HP Q-Sync motor that has at least two operating speeds and 87% peak efficiency compared to incumbent electronically commutated motors (EC or ECM, also known as brushless direct current (DC) motors), the heretofore highest efficiency HVACR fan motor solution, at approximately 82% peak efficiency. The resulting motor prototype built achieved these goals, hitting 90% efficiency and .95 power factor at full load and speed, and 80% efficiency and .7 power factor at half speed. Q-Sync, developed in part through a DOE SBIR grant (Award # DE-SC0006311), is a novel, patented motor technology that improves on electronically commutated permanent magnet motors through an advanced electronic circuit technology. It allows a motor to “sync” with the alternating current (AC) power flow. It does so by eliminating the constant, wasteful power conversions from AC to DC and back to AC through the synthetic creation of a new AC wave on the primary circuit board (PCB) by a process called pulse width modulation (PWM; aka electronic commutation) that is incessantly required to sustain motor operation in an EC permanent magnet motor. The Q-Sync circuit improves the power factor of the motor by removing all

  5. Chlorific efficiency of coal hydrogenation

    Energy Technology Data Exchange (ETDEWEB)

    Schappert, H.

    1942-10-20

    In studies on the calorific efficiency of coal hydrogenation, the efficiency for H/sub 2/ production was calculated to be 26%, the efficiency for hydrogenation was calculated to be 49%, and the efficiency of hydrogenation including H/sub 2/ production was 27.2%. The efficiency of hydrogenation plus hydrogen production was almost equal to the efficiency of hydrogen production alone, even though this was not expected because of the total energy calculated in the efficiency of hydrogenation proper. It was entirely possible, but did not affect computations, that the efficiency of one or the other components of hydrogenation process differed somewhat from 49%. The average efficiency for all cases was 49%. However, when hydrogen was not bought, but was produced--(efficiency of hydrogen production was 26%, not 100%-- then the total energy changed and the efficiency of hydrogen production and combination was not 26%, but 13%. This lower value explained the drop of hydrogenation efficiency to 27.2%.

  6. P53 and p73 differ in their ability to inhibit glucocorticoid receptor (GR transcriptional activity

    Directory of Open Access Journals (Sweden)

    Nie Linghu

    2006-12-01

    Full Text Available Abstract Background p53 is a tumor suppressor and potent inhibitor of cell growth. P73 is highly similar to p53 at both the amino acid sequence and structural levels. Given their similarities, it is important to determine whether p53 and p73 function in similar or distinct pathways. There is abundant evidence for negative cross-talk between glucocorticoid receptor (GR and p53. Neither physical nor functional interactions between GR and p73 have been reported. In this study, we examined the ability of p53 and p73 to interact with and inhibit GR transcriptional activity. Results We show that both p53 and p73 can bind GR, and that p53 and p73-mediated transcriptional activity is inhibited by GR co-expression. Wild-type p53 efficiently inhibited GR transcriptional activity in cells expressing both proteins. Surprisingly, however, p73 was either unable to efficiently inhibit GR, or increased GR activity slightly. To examine the basis for this difference, a series of p53:p73 chimeric proteins were generated in which corresponding regions of either protein have been swapped. Replacing N- and C-terminal sequences in p53 with the corresponding sequences from p73 prevented it from inhibiting GR. In contrast, replacing p73 N- and C-terminal sequences with the corresponding sequences from p53 allowed it to efficiently inhibit GR. Differences in GR inhibition were not related to differences in transcriptional activity of the p53:p73 chimeras or their ability to bind GR. Conclusion Our results indicate that both N- and C-terminal regions of p53 and p73 contribute to their regulation of GR. The differential ability of p53 and p73 to inhibit GR is due, in part, to differences in their N-terminal and C-terminal sequences.

  7. Reactor design for minimizing product inhibition during enzymatic lignocellulose hydrolysis II. Quantification of inhibition and suitability of membrane reactors

    DEFF Research Database (Denmark)

    Andric, Pavle; Meyer, Anne S.; Jensen, Peter Arendt

    2010-01-01

    ideal reactor types, i.e. batch, continuous stirred, and plug-flow, is illustrated quantitatively by modeling different extents of cellulose conversion at different reaction conditions. The main operational challenges of membrane reactors for lignocellulose conversion are highlighted. Key membrane......Product inhibition of cellulolytic enzymes affects the efficiency of the biocatalytic conversion of lignocellulosic biomass to ethanol and other valuable products. New strategies that focus on reactor designs encompassing product removal, notably glucose removal, during enzymatic cellulose...... reactor features, including system set-up, dilution rate, glucose output profile, and the problem of cellobiose are examined to illustrate the quantitative significance of the glucose product inhibition and the total glucose concentration on the cellulolytic conversion rate. Comprehensive overviews...

  8. Self-regulation, ego depletion, and inhibition.

    Science.gov (United States)

    Baumeister, Roy F

    2014-12-01

    Inhibition is a major form of self-regulation. As such, it depends on self-awareness and comparing oneself to standards and is also susceptible to fluctuations in willpower resources. Ego depletion is the state of reduced willpower caused by prior exertion of self-control. Ego depletion undermines inhibition both because restraints are weaker and because urges are felt more intensely than usual. Conscious inhibition of desires is a pervasive feature of everyday life and may be a requirement of life in civilized, cultural society, and in that sense it goes to the evolved core of human nature. Intentional inhibition not only restrains antisocial impulses but can also facilitate optimal performance, such as during test taking. Self-regulation and ego depletion- may also affect less intentional forms of inhibition, even chronic tendencies to inhibit. Broadly stated, inhibition is necessary for human social life and nearly all societies encourage and enforce it. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Energy Efficiency Project Development

    Energy Technology Data Exchange (ETDEWEB)

    IUEP

    2004-03-01

    The International Utility Efficiency Partnerships, Inc. (IUEP) has been a leader among the industry groups that have supported voluntary initiatives to promote international energy efficiency projects and address global climate change. The IUEP maintains its leadership by both supporting international greenhouse gas (GHG) reduction projects under the auspices of the U.S. Department of Energy (DOE) and by partnering with U.S. and international organizations to develop and implement strategies and specific energy efficiency projects. The goals of the IUEP program are to (1) provide a way for U.S. industry to maintain a leadership role in international energy efficiency infrastructure projects; (2) identify international energy project development opportunities to continue its leadership in supporting voluntary market-based mechanisms to reduce GHG emissions; and (3) demonstrate private sector commitment to voluntary approaches to global climate issues. The IUEP is dedicated to identifying, promoting, managing, and assisting in the registration of international energy efficiency projects that result in demonstrated voluntary reductions of GHG emissions. This Final Technical Report summarizes the IUEP's work in identifying, promoting, managing, and assisting in development of these projects and IUEP's effort in creating international cooperative partnerships to support project development activities that develop and deploy technologies that (1) increase efficiency in the production, delivery and use of energy; (2) increase the use of cleaner, low-carbon fuels in processing products; and (3) capture/sequester carbon gases from energy systems. Through international cooperative efforts, the IUEP intends to strengthen partnerships for energy technology innovation and demonstration projects capable of providing cleaner energy in a cost-effective manner. As detailed in this report, the IUEP met program objectives and goals during the reporting period January 1

  10. NSAIDs inhibit tumorigenesis, but how?

    Science.gov (United States)

    Gurpinar, Evrim; Grizzle, William E; Piazza, Gary A

    2014-03-01

    Numerous epidemiologic studies have reported that the long-term use of nonsteroidal anti-inflammatory drugs (NSAID) is associated with a significant decrease in cancer incidence and delayed progression of malignant disease. The use of NSAIDs has also been linked with reduced risk from cancer-related mortality and distant metastasis. Certain prescription-strength NSAIDs, such as sulindac, have been shown to cause regression of precancerous lesions. Unfortunately, the extended use of NSAIDs for chemoprevention results in potentially fatal side effects related to their COX-inhibitory activity and suppression of prostaglandin synthesis. Although the basis for the tumor growth-inhibitory activity of NSAIDs likely involves multiple effects on tumor cells and their microenvironment, numerous investigators have concluded that the underlying mechanism is not completely explained by COX inhibition. It may therefore be possible to develop safer and more efficacious drugs by targeting such COX-independent mechanisms. NSAID derivatives or metabolites that lack COX-inhibitory activity, but retain or have improved anticancer activity, support this possibility. Experimental studies suggest that apoptosis induction and suppression of β-catenin-dependent transcription are important aspects of their antineoplastic activity. Studies show that the latter involves phosphodiesterase inhibition and the elevation of intracellular cyclic GMP levels. Here, we review the evidence for COX-independent mechanisms and discuss progress toward identifying alternative targets and developing NSAID derivatives that lack COX-inhibitory activity but have improved antineoplastic properties. ©2013 AACR

  11. Pharmacological inhibition of poly(ADP-ribose) polymerase inhibits angiogenesis

    International Nuclear Information System (INIS)

    Rajesh, Mohanraj; Mukhopadhyay, Partha; Batkai, Sandor; Godlewski, Grzegorz; Hasko, Gyoergy; Liaudet, Lucas; Pacher, Pal

    2006-01-01

    Poly(ADP-ribose) polymerase (PARP) is a nuclear enzyme which plays an important role in regulating cell death and cellular responses to DNA repair. Pharmacological inhibitors of PARP are being considered as treatment for cancer both in monotherapy as well as in combination with chemotherapeutic agents and radiation, and were also reported to be protective against untoward effects exerted by certain anticancer drugs. Here we show that pharmacological inhibition of PARP with 3-aminobenzamide or PJ-34 dose-dependently reduces VEGF-induced proliferation, migration, and tube formation of human umbilical vein endothelial cells in vitro. These results suggest that treatment with PARP inhibitors may exert additional benefits in various cancers and retinopathies by decreasing angiogenesis

  12. Energy efficiency system development

    Science.gov (United States)

    Leman, A. M.; Rahman, K. A.; Chong, Haw Jie; Salleh, Mohd Najib Mohd; Yusof, M. Z. M.

    2017-09-01

    By subjecting to the massive usage of electrical energy in Malaysia, energy efficiency is now one of the key areas of focus in climate change mitigation. This paper focuses on the development of an energy efficiency system of household electrical appliances for residential areas. Distribution of Questionnaires and pay a visit to few selected residential areas are conducted during the fulfilment of the project as well as some advice on how to save energy are shared with the participants. Based on the collected data, the system developed by the UTHM Energy Team is then evaluated from the aspect of the consumers' behaviour in using electrical appliances and the potential reduction targeted by the team. By the end of the project, 60% of the participants had successfully reduced the electrical power consumption set by the UTHM Energy Team. The reasons for whether the success and the failure is further analysed in this project.

  13. Negotiating Efficient PPP Contracts

    DEFF Research Database (Denmark)

    Tvarnø, Christina D.

    This paper concerns Public Private Partnership (PPP) contracts in concern to the coming new 2014/24IEU public procurement directive. The new EU public procurement directive gives the public authority the opportunity to negotiate PPPs much more when they are implemented in national law....... An opportunity the member states should consider using when procuring a PPP. This paper looks at the negotiation and contracting of a PPP in an economic theoretical and EU public procurement perspective and discusses how to establish an efficient PPP contract under a strong public law doctrine. Governments...... procurement law. Furthermore, the paper seeks to establish a connection between public law, private law and the efficient PPP contract by drawing upon economic theory and empirical contract data from UK, US and Danish partnering contracts from the construction industry and the aim of contracting joint utility...

  14. SparkJet Efficiency

    Science.gov (United States)

    Golbabaei-Asl, Mona; Knight, Doyle; Anderson, Kellie; Wilkinson, Stephen

    2013-01-01

    A novel method for determining the thermal efficiency of the SparkJet is proposed. A SparkJet is attached to the end of a pendulum. The motion of the pendulum subsequent to a single spark discharge is measured using a laser displacement sensor. The measured displacement vs time is compared with the predictions of a theoretical perfect gas model to estimate the fraction of the spark discharge energy which results in heating the gas (i.e., increasing the translational-rotational temperature). The results from multiple runs for different capacitances of c = 3, 5, 10, 20, and 40 micro-F show that the thermal efficiency decreases with higher capacitive discharges.

  15. Superstructure high efficiency photovoltaics

    Science.gov (United States)

    Wagner, M.; So, L. C.; Leburton, J. P.

    1987-01-01

    A novel class of photovoltaic cascade structures is introduced which features multijunction upper subcells. These superstructure high efficiency photovoltaics (SHEP's) exhibit enhanced upper subcell spectral response because of the additional junctions which serve to reduce bulk recombination losses by decreasing the mean collection distance for photogenerated minority carriers. Two possible electrical configurations were studied and compared: a three-terminal scheme that allows both subcells to be operated at their individual maximum power points and a two-terminal configuration with an intercell ohmic contact for series interconnection. The three-terminal devices were found to be superior both in terms of beginning-of-life expectancy and radiation tolerance. Realistic simulations of three-terminal AlGaAs/GaAs SHEP's show that one sun AMO efficiencies in excess of 26 percent are possible.

  16. Efficiency and Logistics

    CERN Document Server

    Hompel, Michael; Klumpp, Matthias

    2013-01-01

    The „EffizienzCluster LogistikRuhr“ was a winner in the Leading Edge Science Cluster competition run by the German federal Ministry of Education and Research. The mission and aim of the „EffizienzCluster LogistikRuhr“ is to facilitate tomorrow’s individuality – in the sense of individual goods supply, mobility, and production – using 75 percent of today’s resources. Efficiency – both in economical and ecological terms – is enabled by state-of-the-art and innovative logistical solutions including transportation, production and intralogistics. These proceedings “Efficiency and Logistics” give first answers from 27 research projects as an insight into the current state of research of Europe’s leading research and development cluster in logistics and as a contribution to the discussion on how logistics as a science can help to cope with foreseeable resource shortage and sustainability as global challenges.

  17. Solar bowl component efficiencies

    International Nuclear Information System (INIS)

    O'Hair, E.A.; Green, B.L.

    1992-01-01

    Battelle Pacific Northwest Laboratory has published two volumes on the economic evaluation of various proposed configurations and plant sizes for the four solar thermal technologies. These are the latest in a series of publications sponsored by the Department of Energy (DOE) on plant and operational costs and are more complete in that they include calculations of electrical output. These latest Battelle volumes use the 1976 solar data from Barstow, Calif., and by calculating or estimating the energy conversion efficiency of each element in the process from sun to electricity predict the output and cost of electricity from different plant sizes for each of the four technologies. In this paper a comparison is presented of the component efficiencies developed by Battelle and those of the solar bowl at Crosbyton, Tex

  18. Efficiently Controllable Graphs.

    Science.gov (United States)

    Gokler, Can; Lloyd, Seth; Shor, Peter; Thompson, Kevin

    2017-06-30

    We investigate graphs that can be disconnected into small components by removing a vanishingly small fraction of their vertices. We show that, when a controllable quantum network is described by such a graph and the gaps in eigenfrequencies and in transition frequencies are bounded exponentially in the number of vertices, the network is efficiently controllable, in the sense that universal quantum computation can be performed using a control sequence polynomial in the size of the network while controlling a vanishingly small fraction of subsystems. We show that networks corresponding to finite-dimensional lattices are efficiently controllable and explore generalizations to percolation clusters and random graphs. We show that the classical computational complexity of estimating the ground state of Hamiltonians described by controllable graphs is polynomial in the number of subsystems or qubits.

  19. Energy efficiency: A proposal

    Directory of Open Access Journals (Sweden)

    Pendić Zoran R.

    2015-01-01

    Full Text Available Increase of energy efficiency in Serbia is one of the priority tasks. Sector of electric lighting offers great opportunities for increasing energy efficiency due to the rapid development of LED technology. Nowadays LED lighting is still expensive and have relatively little application in the domain of electric lighting. However, it is anticipated that LED products would soon greatly transform the electric lighting market. In recent years, LED technology has significantly improved, and constantly evolving. It is expected that advanced and future LED bulbs / lamps to be getting cheaper and with a better technical characteristics and that they will soon be dominant on the lighting market. Serbia must prepare for the LED future, creating appropriate legislation and promotion of appropriate incentive measures.

  20. CONTROLLING AND BUSINESS EFFICIENCY

    OpenAIRE

    Vuko, Tina; Ojvan, Ivica

    2013-01-01

    Managing business successfully in dynamic environment requires effective controlling system. Controlling is the process of defining objectives, planning and management control so that every decision maker can act in accordance with agreed objectives. Controlling function as a separate department contributes business efficiency trough ensuring transparency of business result and business processes. Controlling takes place when manager and controller cooperate. The aim of this paper is to inves...

  1. Carbon Efficient Building Solutions

    Directory of Open Access Journals (Sweden)

    Pellervo Matilainen

    2010-03-01

    Full Text Available Traditionally, the Finnish legislation have focused on energy use and especially on energy used for heating space in buildings. However, in many cases this does not lead to the optimal concept in respect to minimizing green house gases. This paper studies how CO2 emission levels are affected by different measures to reduce energy use in buildings. This paper presents two real apartment buildings with different options of energy efficiency and power sources. The calculations clearly show that in the future electricity and domestic hot water use will have high importance in respect to energy efficiency, and therefore also CO2 equivalent (eq emissions. The importance increases when the energy efficiency of the building increases. There are big differences between average Finnish production and individual power plants; CO2 eq emissions might nearly double depending on the energy source and the power plant type. Both a building with an efficient district heating as a power source, and a building with ground heat in addition to nuclear power electricity as a complimentary electricity source performed very similarly to each other in respect to CO2 eq emissions. However, it is dangerous to conclude that it is not important which energy source is chosen. If hypothetically, the use of district heating would dramatically drop, the primary energy factor and CO2 eq emissions from electricity would rise, which in turn would lead to the increase of the ground heat systems emissions. A problem in the yearly calculations is that the fact that it is very important, sometimes even crucial, when energy is needed, is always excluded.

  2. Determinants of Government Efficiency

    OpenAIRE

    David Hauner; Annette J Kyobe

    2008-01-01

    We compile the first large cross-country panel dataset of public sector performance and efficiency, encompassing 114 countries on all income levels from 1980 to 2006, with about 1,800 country-year observations for the education sector and about 900 observations for health. We regress these indicators on potential economic, institutional, demographic, and geographic determinants. Our most resounding conclusion is that higher government expenditure relative to GDP tends to be associated with lo...

  3. Measuring Tax Efficiency

    DEFF Research Database (Denmark)

    Raimondos-Møller, Pascalis; Woodland, Alan D.

    2004-01-01

    , thereby, the degree of efficiency of a taxsystem. We call this number the Tax Optimality Index. We show howthe basic method can be altered in order to derive a revenue equivalentuniform tax, which measures the size of the public sector. A numericalexample is used to illustrate the method developed.......JEL Code: H21, H41.Keywords: Tax optimality index, excess burden, distance function.Authors Affiliations: Raimondos-Møller: Copenhagen Business School, CEPR,CESifo, and EPRU. Woodland: University of Sydney....

  4. SOURgraphs for efficient completion

    OpenAIRE

    Christopher Lynch; Polina Strogova

    1998-01-01

    We introduce a data structure called SOUR graphs and present an efficient Knuth-Bendix completion procedure based on it. SOUR graphs allow for a maximal structure sharing of terms in rewriting systems. The term representation is a dag representation, except that edges are labelled with equational constraints and variable renamings. The rewrite rules correspond to rewrite edges, the unification problems to unification edges. The Critical Pair and Simplification inferences are recogniz...

  5. Efficient Non Linear Loudspeakers

    DEFF Research Database (Denmark)

    Petersen, Bo R.; Agerkvist, Finn T.

    2006-01-01

    Loudspeakers have traditionally been designed to be as linear as possible. However, as techniques for compensating non linearities are emerging, it becomes possible to use other design criteria. This paper present and examines a new idea for improving the efficiency of loudspeakers at high levels...... by changing the voice coil layout. This deliberate non-linear design has the benefit that a smaller amplifier can be used, which has the benefit of reducing system cost as well as reducing power consumption....

  6. Efficient HVAC. New products

    International Nuclear Information System (INIS)

    2016-01-01

    Jung is responding to the challenge of energy efficiency, ease of operation and economic profitability in all of its solutions for the tertiary sector, whether for newly constructed buildings or refurbishments, for full management of the electrical system or the partial control of lighting, HVAC, mood settings, access control, etc., for the bedrooms or specific areas of the building. In the specific case of hotels, Jung offers each a custom-made solution in line with its possibilities and objectives. (Author)

  7. Energy efficiency fallacies revisited

    International Nuclear Information System (INIS)

    Brookes, Leonard

    2000-01-01

    A number of governments including that of the UK subscribe to the belief that a national program devoted to raising energy efficiency throughout the economy provides a costless - indeed profitable - route to meeting international environmental obligations. This is a seductive policy. It constitutes the proverbial free lunch - not only avoiding politically unpopular measures like outlawing, taxing or rationing offending fuels or expanding non-carboniferous sources of energy like nuclear power but doing so with economic benefit. The author of this contribution came to doubt the validity of this solution when it was offered as a way of mitigating the effect of the OPEC price hikes of the 1970s, maintaining that economically justified improvement in energy efficiency led to higher levels of energy consumption at the economy-wide level than in the absence of any efficiency response. More fundamentally, he argues that there is no case for preferentially singling out energy, from among all the resources available to us, for efficiency maximisation. The least damaging policy is to determine targets, enact the restrictive measures needed to curb consumption, and then leave it to consumers - intermediate and final - to reallocate all the resources available to them to best effect subject to the new enacted constraints and any others they might be experiencing. There is no reason to suppose that it is right for all the economic adjustment following a new resource constraint to take the form of improvements in the productivity of that resource alone. As many others have argued, any action to impose resource constraint entails an inevitable economic cost in the shape of a reduction in production and consumption possibilities: there would be no free lunch. In the last few years debate about the validity of these contentions has blossomed, especially under the influence of writers on the western side of the Atlantic. In this contribution the author outlines the original arguments

  8. Selective and nonselective inhibition of competitors in picture naming

    NARCIS (Netherlands)

    Shao, Z.; Meyer, A.S.; Roelofs, A.P.A.

    2013-01-01

    The present study examined the relation between nonselective inhibition and selective inhibition in picture naming performance. Nonselective inhibition refers to the ability to suppress any unwanted response, whereas selective inhibition refers to the ability to suppress specific competing

  9. Greener Approach towards Corrosion Inhibition

    Directory of Open Access Journals (Sweden)

    Neha Patni

    2013-01-01

    Full Text Available Corrosion control of metals is technically, economically, environmentally, and aesthetically important. The best option is to use inhibitors for protecting metals and alloys against corrosion. As organic corrosion inhibitors are toxic in nature, so green inhibitors which are biodegradable, without any heavy metals and other toxic compounds, are promoted. Also plant products are inexpensive, renewable, and readily available. Tannins, organic amino acids, alkaloids, and organic dyes of plant origin have good corrosion-inhibiting abilities. Plant extracts contain many organic compounds, having polar atoms such as O, P, S, and N. These are adsorbed on the metal surface by these polar atoms, and protective films are formed, and various adsorption isotherms are obeyed. Various types of green inhibitors and their effect on different metals are mentioned in the paper.

  10. High-efficiency CARM

    Energy Technology Data Exchange (ETDEWEB)

    Bratman, V.L.; Kol`chugin, B.D.; Samsonov, S.V.; Volkov, A.B. [Institute of Applied Physics, Nizhny Novgorod (Russian Federation)

    1995-12-31

    The Cyclotron Autoresonance Maser (CARM) is a well-known variety of FEMs. Unlike the ubitron in which electrons move in a periodical undulator field, in the CARM the particles move along helical trajectories in a uniform magnetic field. Since it is much simpler to generate strong homogeneous magnetic fields than periodical ones for a relatively low electron energy ({Brit_pounds}{le}1-3 MeV) the period of particles` trajectories in the CARM can be sufficiently smaller than in the undulator in which, moreover, the field decreases rapidly in the transverse direction. In spite of this evident advantage, the number of papers on CARM is an order less than on ubitron, which is apparently caused by the low (not more than 10 %) CARM efficiency in experiments. At the same time, ubitrons operating in two rather complicated regimes-trapping and adiabatic deceleration of particles and combined undulator and reversed guiding fields - yielded efficiencies of 34 % and 27 %, respectively. The aim of this work is to demonstrate that high efficiency can be reached even for a simplest version of the CARM. In order to reduce sensitivity to an axial velocity spread of particles, a short interaction length where electrons underwent only 4-5 cyclotron oscillations was used in this work. Like experiments, a narrow anode outlet of a field-emission electron gun cut out the {open_quotes}most rectilinear{close_quotes} near-axis part of the electron beam. Additionally, magnetic field of a small correcting coil compensated spurious electron oscillations pumped by the anode aperture. A kicker in the form of a sloping to the axis frame with current provided a control value of rotary velocity at a small additional velocity spread. A simple cavity consisting of a cylindrical waveguide section restricted by a cut-off waveguide on the cathode side and by a Bragg reflector on the collector side was used as the CARM-oscillator microwave system.

  11. Adsorption and corrosion inhibition of mild steel in acidic media by expired pharmaceutical drug

    Directory of Open Access Journals (Sweden)

    P. Geethamani

    2015-12-01

    Full Text Available The inhibitive action of an examined expired Ambroxol drug on the corrosion of mild steel in 1 M HCl and 1 M H2SO4 acid medium has been studied by weight loss and electrochemical techniques. The weight loss techniques result was discussed. The inhibition efficiency increases with increasing the concentration of the inhibitor. Electrochemical studies data support that examined expired drug is an efficient inhibitor for mild steel corrosion. The adsorption of the examined drug obeys Langmuir’s adsorption isotherm. Polarization studies indicate that this inhibitor acts as a mixed type inhibition. The various thermodynamic parameters were calculated and discussed. The protective film formed on the surface was confirmed by SEM. The data collected from the studied techniques are in good agreement to confirm the ability of using expired Ambroxol drug as corrosion inhibitor for mild steel in both acid media.

  12. Research on the inhibition mechanism of tetraphenylporphyrin on AZ91D magnesium alloy

    International Nuclear Information System (INIS)

    Hu, Junying; Huang, Daobing; Zhang, Guoan; Song, Guang-Ling; Guo, Xingpeng

    2012-01-01

    Highlights: ► Environment-friendly tetraphenylporphyrin is synthesized in the lab. ► The tetraphenylporphyrin can efficiently inhibit AZ91D corrosion. ► The inhibitor chelates with Mg ions to form a film retarding Mg dissolution. - Abstract: 5,10,15,20-Tetraphenylporphyrin (TPP) is synthesized and its inhibition effect on AZ91D magnesium alloy in 0.05 wt.% NaCl solution is studied. Electrochemical measurement and immersion corrosion test results indicate that the inhibition efficiency of TPP reaches 90%. SEM, FT-IR, ultraviolet–visible absorption spectrum (UV), fluorescent spectrometry and XPS analyses suggest that TPP molecules can chelate with Mg via their N atoms to form a TPP–Mg complex, which can precipitate as a film on AZ91D alloy. The precipitated TPP–Mg reduces the porosity of the original Mg(OH) 2 surface film and retards the dissolution of the Mg alloy.

  13. Quantum mechanical and electrochemical investigations on corrosion inhibition properties of novel heterocyclic Schiff bases

    Directory of Open Access Journals (Sweden)

    Nimmy Kuriakose

    2017-07-01

    Full Text Available The corrosion inhibition efficiencies of two novel Schiff bases, namely (E-3-[thiophen-2-ylmethyleneamino]benzoic acid (T2YMABA and (E-4-(5-[(2-phenylhydrazono methyl]thiophen-2-ylbenzoic acid (PHMT2YBA on mild steel (MS in 1.0M HCl solution has been investigated and compared using electrochemical impedance spectroscopy and potentiodynamic polarization analysis. The Schiff bases exhibited very good corrosion inhibitions on mild steel in 1.0M HCl medium and the inhibition efficiency increased with the increase in concentration of the inhibitor. Polarization studies revealed that T2YMABA acted as a mixed type inhibitor whereas PHMT2YBA molecules acted as anodic inhibitor.

  14. Corrosion Inhibition of Mild Steel in Citric Acid by Aqueous Extract of Piper Nigrum L.

    Directory of Open Access Journals (Sweden)

    P. Matheswaran

    2012-01-01

    Full Text Available The inhibition efficiency (IE of an aqueous extract of Piper Nigrum L. in controlling corrosion of mild steel at pH 12 has been evaluated by weight loss method in the absence and presence of inhibitor in citric acid medium at different concentration. The result showed that the corrosion inhibition efficiency of these compounds was found to vary with the different concentration at two hour time interval at room temperature. Also, it was found that the corrosion inhibition behaviour of Piper Nigrum L. is greater in 2 N Citric acid than 1 N Citric acid medium. So Piper Nigrum L. can be used has a good inhibitor for preventing mild steel material which is used in many construction purpose.

  15. Corrosion inhibition of carbon steel XC70 in H 2 SO 4 solution by ...

    African Journals Online (AJOL)

    In this work, we studied the efficiency of corrosion inhibition of carbon steel XC70 in H2SO4 0.5 M aqueous solution using ferrocenyl derivatives synthesized in our laboratory, this compound is: 3-(ferrocenylmethylamine)benzonitrile. The inhibitory potential of this compound was determined by electrochemical techniques ...

  16. Eliminating inhibition of enzymatic hydrolysis by lignosulfonate in unwashed sulfite-pretreated aspen using metal salts

    Science.gov (United States)

    Hao Liu; Junyong Zhu

    2010-01-01

    This study demonstrated the efficiency of Ca(II) and Mg(II) in removing inhibition of enzymatic hydrolysis by lignosulfonate through non-productive adsorption of enzymes. Adding 1 mmol/g cellulose of either metal salt restores approximately 65% of the activity lost when a pure cellulose/cellulase solution is spiked with lignosulfonate. Addition of either Ca(II) or Mg(...

  17. Corrosion Inhibition of Titanium in Acidic Media Containing Fluoride with Bixin

    OpenAIRE

    Jinendra Singh Chauhan; D. K. Gupta

    2009-01-01

    The bixin in acidic media were tested for corrosion inhibition of Ti in 0.5 N sulphuric acid and 0.1 N HCl solution at 30 to 40 °C temperature range by electrochemical methods. It reveals that bixin works as a corrosion inhibitor in halide media and protect the metals from the corrosion with great efficiency

  18. Corrosion Inhibition of Titanium in Acidic Media Containing Fluoride with Bixin

    Directory of Open Access Journals (Sweden)

    Jinendra Singh Chauhan

    2009-01-01

    Full Text Available The bixin in acidic media were tested for corrosion inhibition of Ti in 0.5 N sulphuric acid and 0.1 N HCl solution at 30 to 40 °C temperature range by electrochemical methods. It reveals that bixin works as a corrosion inhibitor in halide media and protect the metals from the corrosion with great efficiency

  19. Cost efficient command management

    Science.gov (United States)

    Brandt, Theresa; Murphy, C. W.; Kuntz, Jon; Barlett, Tom

    1996-01-01

    The design and implementation of a command management system (CMS) for a NASA control center, is described. The technology innovations implemented in the CMS provide the infrastructure required for operations cost reduction and future development cost reduction through increased operational efficiency and reuse in future missions. The command management design facilitates error-free operations which enables the automation of the routine control center functions and allows for the distribution of scheduling responsibility to the instrument teams. The reusable system was developed using object oriented methodologies.

  20. Energy Efficient Digital Networks

    Energy Technology Data Exchange (ETDEWEB)

    Lanzisera, Steven [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Brown, Richard [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2013-01-01

    Digital networks are the foundation of the information services, and play an expanding and indispensable role in our lives, via the Internet, email, mobile phones, etc. However, these networks consume energy, both through the direct energy use of the network interfaces and equipment that comprise the network, and in the effect they have on the operating patterns of devices connected to the network. The purpose of this research was to investigate a variety of technology and policy issues related to the energy use caused by digital networks, and to further develop several energy-efficiency technologies targeted at networks.

  1. Merging {DBMs} Efficiently

    DEFF Research Database (Denmark)

    David, Alexandre

    2005-01-01

    In this paper we present different algorithms to reduce the number of DBMs in federations by merging them. Federations are unions of DBMs and are used to represent non-convex zones. Inclusion checking between DBMs is a limited technique to reduce the size of federations and how to choose some DBMs...... to merge them into a larger one is a combi-natorial problem. We present a number of simple but efficient techniques to avoid searching the combinations while still being able to merge any number of DBMs...

  2. Improving efficiency in stereology

    DEFF Research Database (Denmark)

    Keller, Kresten Krarup; Andersen, Ina Trolle; Andersen, Johnnie Bremholm

    2013-01-01

    of the study was to investigate the time efficiency of the proportionator and the autodisector on virtual slides compared with traditional methods in a practical application, namely the estimation of osteoclast numbers in paws from mice with experimental arthritis and control mice. Tissue slides were scanned...... in a digital slide scanner and the autodisector was applied on the obtained virtual tissue slides. Every slide was partitioned into fields of view, and cells were counted in all of them. Based on the original exhaustive data set comprising 100% of fields of view and covering the total section area...

  3. Late Washing efficiency

    International Nuclear Information System (INIS)

    Morrissey, M.F.

    1992-01-01

    Interim Waste Technology has demonstrated the Late Washing concept on the Experimental Laboratory Filter (ELF) at TNX. In two tests, washing reduced the [NO 2 - ] from 0.08 M to approximately 0.01 M on slurries with 2 year equivalent radiation exposures and 9.5 wt. % solids. For both washes, the [NO 2 - ] decreased at rates near theoretical for a constant volume stirred vessel, indicating approximately l00% washing efficiency. Permeate flux was greater than 0.05 gpm/ft 2 for both washes at a transmembrane pressure of 50 psi and flow velocity of 9 ft/sec

  4. Fuze Gear Train Efficiency

    Science.gov (United States)

    1981-11-01

    P6.06. S a1.0 POINTIFr .94;11 ALPHA)) -02 .O~ 5 La1. POINTEr a94 AIPHA)) a Pfl.3E S *1.0 P’) INTEF a 94149 AIPHAO a Pnl*h& S v 1.0 POINTirr a .949!. ALPHA...conditions, the point efficiency is computed according to equation 3 (ref E-1), i.e., Cŕ PO INTEF KRA 3IO M-in where, withb Ka lt ny The cycle

  5. Energy efficient data centers

    Energy Technology Data Exchange (ETDEWEB)

    Tschudi, William; Xu, Tengfang; Sartor, Dale; Koomey, Jon; Nordman, Bruce; Sezgen, Osman

    2004-03-30

    Data Center facilities, prevalent in many industries and institutions are essential to California's economy. Energy intensive data centers are crucial to California's industries, and many other institutions (such as universities) in the state, and they play an important role in the constantly evolving communications industry. To better understand the impact of the energy requirements and energy efficiency improvement potential in these facilities, the California Energy Commission's PIER Industrial Program initiated this project with two primary focus areas: First, to characterize current data center electricity use; and secondly, to develop a research ''roadmap'' defining and prioritizing possible future public interest research and deployment efforts that would improve energy efficiency. Although there are many opinions concerning the energy intensity of data centers and the aggregate effect on California's electrical power systems, there is very little publicly available information. Through this project, actual energy consumption at its end use was measured in a number of data centers. This benchmark data was documented in case study reports, along with site-specific energy efficiency recommendations. Additionally, other data center energy benchmarks were obtained through synergistic projects, prior PG&E studies, and industry contacts. In total, energy benchmarks for sixteen data centers were obtained. For this project, a broad definition of ''data center'' was adopted which included internet hosting, corporate, institutional, governmental, educational and other miscellaneous data centers. Typically these facilities require specialized infrastructure to provide high quality power and cooling for IT equipment. All of these data center types were considered in the development of an estimate of the total power consumption in California. Finally, a research ''roadmap'' was developed

  6. Cellulase Inhibition by High Concentrations of Monosaccharides

    DEFF Research Database (Denmark)

    Hsieh, Chia-Wen; Cannella, David; Jørgensen, Henning

    2014-01-01

    Biological degradation of biomass on an industrial scale culminates in high concentrations of end products. It is known that the accumulation of glucose and cellobiose, end products of hydrolysis, inhibit cellulases and decrease glucose yields. Aside from these end products, however, other monosa...... glucose. Protein adsorption studies showed that this inhibition e ff ect was most likely due to catalytic, and not binding, inhibition of the cellulases....

  7. Inhibiting Effect of Nicotinic Acid Hydrazide on Corrosion of Aluminum and Mild Steel in Acidic Medium

    International Nuclear Information System (INIS)

    Bhat, J. Ishwara; Alva, Vijaya D. P.

    2014-01-01

    The corrosion behavior of aluminum and mild steel in hydrochloric acid medium was studied using a nicotinic acid hydrazide as inhibitor by potentiodynamic polarization, electrochemical impedance spectroscopy technique and gravimetric methods. The effects of inhibitor concentration and temperature were investigated. The experimental results suggested, nicotinic acid hydrazide is a good corrosion inhibitor for both aluminum and mild steel in hydrochloric acid medium and the inhibition efficiency increased with increase in the inhibitor concentration. The polarization studies revealed that nicotinic acid hydrazide exhibits mixed type of inhibition. The inhibition was assumed to occur via adsorption of the inhibitor molecules on the aluminum and mild steel surface and inhibits corrosion by blocking the reaction sites on the surface of aluminum

  8. Differential inhibition of organic cations by the renal tubule of the chicken: relationship to Tm

    Energy Technology Data Exchange (ETDEWEB)

    Springate, J.; Hasan, M.; Rennick, B.; Acara, M.

    1986-03-01

    The ability of organic cations to differentially inhibit the renal excretion of two prototypical organic cations, tetraethylammonium (TEA) and N/sup 1/-methylnicotinamide (NMN), was investigated using the Sperber technique in chickens. /sup 3/H-TEA and /sup 14/C-NMN were infused simultaneously into the renal portal circulation and their transport efficiencies (TE) determined to be 106 +/- 11% and 81 +/- 13% respectively. Quinine, unlabelled NMN or TEA, added in increasing amounts, produced differential inhibition of TEA, NMN, or cimetidine (infused in separate experiments). Data using other competing organic cations (guinidine, ranitidine, triethylcholine) indicated that TEA was never more susceptible to inhibition than NMN. These results suggest that the magnitude of T/sub m/ is directly related to susceptibility to inhibition and indirectly to inhibitory potency.

  9. Characterization and Antioxidant Properties of Six Algerian Propolis Extracts: Ethyl Acetate Extracts Inhibit Myeloperoxidase Activity

    Directory of Open Access Journals (Sweden)

    Yasmina Mokhtaria Boufadi

    2014-02-01

    Full Text Available Because propolis contains many types of antioxidant compounds such as polyphenols and flavonoids, it can be useful in preventing oxidative damages. Ethyl acetate extracts of propolis from several Algerian regions show high activity by scavenging free radicals, preventing lipid peroxidation and inhibiting myeloperoxidase (MPO. By fractioning and assaying ethyl acetate extracts, it was observed that both polyphenols and flavonoids contribute to these activities. A correlation was observed between the polyphenol content and the MPO inhibition. However, it seems that kaempferol, a flavonoid, contributes mainly to the MPO inhibition. This molecule is in a high amount in the ethyl acetate extract and demonstrates the best efficiency towards the enzyme with an inhibiting concentration at 50% of 4 ± 2 µM.

  10. The efficient learner.

    Science.gov (United States)

    Almåsbakk, B; Whiting, H T; Helgerud, J

    2001-02-01

    The research to be reported examines the concept of efficiency, defined as the relation of metabolic energy expended to mechanical work done. The development of movement coordination was investigated in the context of the hypothesis that an increase in coordination would be accompanied by a parallel reduction in overall energy expenditure, relative to the increase in energy expenditure demanded by improvements in work output. The task involved learning to make cyclical, slalom-like, ski movements on a ski apparatus. Development of coordination was indexed by changes in the timing of forcing while on-line measurements of oxygen consumption were used as indices of energy expenditure. Six female volunteers served as subjects in nine training sessions. The change in the coordination pattern, between the subject and the apparatus, as indexed by the development of the phase lag, was paralleled by an improvement in efficiency. It was concluded that learning the skill used in this study involves a search by the system for perception-action couplings (phase relations in the present study) that require minimal energy expenditure.

  11. Negotiating Efficient PPP Contracts

    DEFF Research Database (Denmark)

    Tvarnø, Christina D.

    This paper concerns Public Private Partnership (PPP) contracts in concern to the coming new 2014/24IEU public procurement directive. The new EU public procurement directive gives the public authority the opportunity to negotiate PPPs much more when they are implemented in national law. An opportu......This paper concerns Public Private Partnership (PPP) contracts in concern to the coming new 2014/24IEU public procurement directive. The new EU public procurement directive gives the public authority the opportunity to negotiate PPPs much more when they are implemented in national law....... An opportunity the member states should consider using when procuring a PPP. This paper looks at the negotiation and contracting of a PPP in an economic theoretical and EU public procurement perspective and discusses how to establish an efficient PPP contract under a strong public law doctrine. Governments...... procurement law. Furthermore, the paper seeks to establish a connection between public law, private law and the efficient PPP contract by drawing upon economic theory and empirical contract data from UK, US and Danish partnering contracts from the construction industry and the aim of contracting joint utility...

  12. Mini-review: Inhibition of biofouling by marine microorganisms.

    Science.gov (United States)

    Dobretsov, Sergey; Abed, Raeid M M; Teplitski, Max

    2013-01-01

    Any natural or artificial substratum exposed to seawater is quickly fouled by marine microorganisms and later by macrofouling species. Microfouling organisms on the surface of a substratum form heterogenic biofilms, which are composed of multiple species of heterotrophic bacteria, cyanobacteria, diatoms, protozoa and fungi. Biofilms on artificial structures create serious problems for industries worldwide, with effects including an increase in drag force and metal corrosion as well as a reduction in heat transfer efficiency. Additionally, microorganisms produce chemical compounds that may induce or inhibit settlement and growth of other fouling organisms. Since the last review by the first author on inhibition of biofouling by marine microbes in 2006, significant progress has been made in the field. Several antimicrobial, antialgal and antilarval compounds have been isolated from heterotrophic marine bacteria, cyanobacteria and fungi. Some of these compounds have multiple bioactivities. Microorganisms are able to disrupt biofilms by inhibition of bacterial signalling and production of enzymes that degrade bacterial signals and polymers. Epibiotic microorganisms associated with marine algae and invertebrates have a high antifouling (AF) potential, which can be used to solve biofouling problems in industry. However, more information about the production of AF compounds by marine microorganisms in situ and their mechanisms of action needs to be obtained. This review focuses on the AF activity of marine heterotrophic bacteria, cyanobacteria and fungi and covers publications from 2006 up to the end of 2012.

  13. Inhibition of glycolysis by misonidazole in hypoxic cells

    International Nuclear Information System (INIS)

    Ling, L.; Sutherland, R.

    1984-01-01

    Inhibition of glycolysis has been postulated to be a mechanism of misonidazole (MISO) toxicity in hypoxic cells. To investigate the effect of MISO on glycolysis, glucose transport and its consumption and lactate formation were measured. Exponential EMT6 cells (10/sup 6/ cells/ml) were made hypoxix by continuous gassing in 3% CO/sub 2/ in N/sub 2/. They were then treated with 5mM MISO for various times, then washed and analysed for their rates of anaerobic glycolysis. Glucose and lactate content were determined enzymatically. The rates of both glucose consumption and lactate formation decreased after 30 min hypoxic incubation with MISO. After 90 min, the rates were not measurable even though the cells still excluded Trypan Blue. There was, however, a parallel decrease in plating efficiency. These data suggest that the inhibition of glycolysis is an important mechanism of hypoxic toxicity of MISO. To locate the site of inhibition, studies were initiated to look at glucose transport by following the uptake of /sup 14/-C-3-0-methyl-glucose, a nonmetabolised glucose analog. Results obtained so far indicate that up to 90 min of hypoxic incubation with MISO, there was no change in the kinetics of the uptake of his analog. Therefore, the results showed that in hypoxic cells treated with MISO, the glucose transport system was unaffected. However, there was a rapid decrease in anaerobic glycolysis

  14. Visual working memory supports the inhibition of previously processed information: evidence from preview search.

    Science.gov (United States)

    Al-Aidroos, Naseem; Emrich, Stephen M; Ferber, Susanne; Pratt, Jay

    2012-06-01

    In four experiments we assessed whether visual working memory (VWM) maintains a record of previously processed visual information, allowing old information to be inhibited, and new information to be prioritized. Specifically, we evaluated whether VWM contributes to the inhibition (i.e., visual marking) of previewed distractors in a preview search. We evaluated this proposal by testing three predictions. First, Experiments 1 and 2 demonstrate that preview inhibition is more effective when the number of previewed distractors is below VWM capacity than above; an effect that can only be observed at small preview set sizes (Experiment 2A) and when observers are allowed to move their eyes freely (Experiment 2B). Second, Experiment 3 shows that, when quantified as the number of inhibited distractors, the magnitude of the preview effect is stable across different search difficulties. Third, Experiment 4 demonstrates that individual differences in preview inhibition are correlated with individual differences in VWM capacity. These findings provide converging evidence that VWM supports the inhibition of previewed distractors. More generally, these findings demonstrate how VWM contributes to the efficiency of human visual information processing--VWM prioritizes new information by inhibiting old information from being reselected for attention.

  15. Efficient Turbulence Modeling for CFD Wake Simulations

    DEFF Research Database (Denmark)

    van der Laan, Paul

    , that can accurately and efficiently simulate wind turbine wakes. The linear k-ε eddy viscosity model (EVM) is a popular turbulence model in RANS; however, it underpredicts the velocity wake deficit and cannot predict the anisotropic Reynolds-stresses in the wake. In the current work, nonlinear eddy...... viscosity models (NLEVM) are applied to wind turbine wakes. NLEVMs can model anisotropic turbulence through a nonlinear stress-strain relation, and they can improve the velocity deficit by the use of a variable eddy viscosity coefficient, that delays the wake recovery. Unfortunately, all tested NLEVMs show...... numerically unstable behavior for fine grids, which inhibits a grid dependency study for numerical verification. Therefore, a simpler EVM is proposed, labeled as the k-ε - fp EVM, that has a linear stress-strain relation, but still has a variable eddy viscosity coefficient. The k-ε - fp EVM is numerically...

  16. Working Memory Capacity and Redundant Information Processing Efficiency

    Directory of Open Access Journals (Sweden)

    Michael John Endres

    2015-05-01

    Full Text Available Working memory capacity (WMC is typically measured by the amount of task-relevant information an individual can keep in mind while resisting distraction or interference from task irrelevant information. The current research investigated the extent to which differences in WMC were associated with performance on a novel redundant memory probes (RMP task that systematically varied the amount of to-be-remembered (targets and to-be-ignored (distractor information. The RMP task was designed to both facilitate and inhibit working memory search processes, as evidenced by differences in accuracy, response time, and Linear Ballistic Accumulator (LBA model estimates of information processing efficiency. Participants (N = 170 completed standard intelligence tests and dual-span WMC tasks, along with the RMP task. As expected, accuracy, response-time, and LBA model results indicated memory search and retrieval processes were facilitated under redundant- target conditions, but also inhibited under mixed target/distractor and redundant-distractor conditions. Repeated measures analyses also indicated that, while individuals classified as high (n = 85 and low (n = 85 WMC did not differ in the magnitude of redundancy effects, groups did differ in the efficiency of memory search and retrieval processes overall. Results suggest that redundant information reliably facilitates and inhibits the efficiency or speed of working memory search, and these effects are independent of more general limits and individual differences in the capacity or space of working memory.

  17. ENERGY EFFICIENT DESALINATOR

    Directory of Open Access Journals (Sweden)

    T. A. Ismailov

    2017-01-01

    Full Text Available Objectives. The aim of the research is to develop a thin-film semiconductor thermoelectric heat pump of cylindrical shape for the desalination of sea water.Methods. To improve the efficiency of the desalination device, a  special thin-film semiconductor thermoelectric heat pump of  cylindrical shape is developed. The construction of the thin-film  semiconductor thermoelectric heat pump allows the flow rates of  incoming sea water and outflowing fresh water and brine to be  equalised by changing the geometric dimensions of the desalinator.  The cross-sectional area of the pipeline for incoming sea water is equal to the total area of outflowing fresh water and brine.Results. The use of thin-film semiconductor p- and n-type branches  in a thermo-module reduces their electrical resistance virtually to  zero and completely eliminates Joule's parasitic heat release. The  Peltier thermoelectric effect on heating and cooling is completely  preserved, bringing the efficiency of the heat pump to almost 100%, improving the energy-saving characteristics of the  desalinator as a whole. To further increase the efficiency of the  proposed desalinator, thermoelectric modules with radiation can be  used as thermoelectric devices.Conclusion. As a consequence of the creation of conditions of high rarefaction under which water will be converted to steam, which, at  20° C, is cold (as is the condensed distilled water, energy costs can  be reduced. In this case, the energy for heating and cooling is not  wasted; moreover, sterilisation is also achieved using the ultraviolet  radiation used in the thermoelectric devices, which, on the one hand, generate electromagnetic ultraviolet radiation, and, on the other, cooling. Such devices operate in optimal mode without heat  release. The desalination device can be used to produce fresh water and concentrated solutions from any aqueous solutions, including wastewater from industrial

  18. Refines Efficiency Improvement

    Energy Technology Data Exchange (ETDEWEB)

    WRI

    2002-05-15

    Refinery processes that convert heavy oils to lighter distillate fuels require heating for distillation, hydrogen addition or carbon rejection (coking). Efficiency is limited by the formation of insoluble carbon-rich coke deposits. Heat exchangers and other refinery units must be shut down for mechanical coke removal, resulting in a significant loss of output and revenue. When a residuum is heated above the temperature at which pyrolysis occurs (340 C, 650 F), there is typically an induction period before coke formation begins (Magaril and Aksenova 1968, Wiehe 1993). To avoid fouling, refiners often stop heating a residuum before coke formation begins, using arbitrary criteria. In many cases, this heating is stopped sooner than need be, resulting in less than maximum product yield. Western Research Institute (WRI) has developed innovative Coking Index concepts (patent pending) which can be used for process control by refiners to heat residua to the threshold, but not beyond the point at which coke formation begins when petroleum residua materials are heated at pyrolysis temperatures (Schabron et al. 2001). The development of this universal predictor solves a long standing problem in petroleum refining. These Coking Indexes have great potential value in improving the efficiency of distillation processes. The Coking Indexes were found to apply to residua in a universal manner, and the theoretical basis for the indexes has been established (Schabron et al. 2001a, 2001b, 2001c). For the first time, a few simple measurements indicates how close undesired coke formation is on the coke formation induction time line. The Coking Indexes can lead to new process controls that can improve refinery distillation efficiency by several percentage points. Petroleum residua consist of an ordered continuum of solvated polar materials usually referred to as asphaltenes dispersed in a lower polarity solvent phase held together by intermediate polarity materials usually referred to as

  19. Information Systems Efficiency Model

    Directory of Open Access Journals (Sweden)

    Milos Koch

    2017-07-01

    Full Text Available This contribution discusses the basic concept of creating a new model for the efficiency and effectiveness assessment of company information systems. The present trends in this field are taken into account, and the attributes are retained of measuring the optimal solutions for a company’s ICT (the implementation, functionality, service, innovations, safety, relationships, costs, etc.. The proposal of a new model of assessment comes from our experience with formerly implemented and employed methods, methods which we have modified in time and adapted to companies’ needs but also to the necessaries of our research that has been done through the ZEFIS portal. The most noteworthy of them is the HOS method that we have discussed in a number of forums. Its main feature is the fact that it respects the complexity of an information system in correlation with the balanced state of its individual parts.

  20. CONTROLLING AND BUSINESS EFFICIENCY

    Directory of Open Access Journals (Sweden)

    Tina Vuko

    2013-02-01

    Full Text Available Managing business successfully in dynamic environment requires effective controlling system. Controlling is the process of defining objectives, planning and management control so that every decision maker can act in accordance with agreed objectives. Controlling function as a separate department contributes business efficiency trough ensuring transparency of business result and business processes. Controlling takes place when manager and controller cooperate. The aim of this paper is to investigate the effectiveness of controlling function (i.e. controlling department in Croatian companies and to address the specific features of the function that contribute significantly to overall business performance. The research is conducted on the sample of companies listed on the Regulated market of the Zagreb Stock Exchange. Survey is used as a method to collect the data regarding the controlling function, while financial data necessary for the research are extracted from the published financial statements. Results of the research indicate that controlling department has positive effects on the business performance.

  1. SOURgraphs for efficient completion

    Directory of Open Access Journals (Sweden)

    Christopher Lynch

    1998-12-01

    Full Text Available We introduce a data structure called SOUR graphs and present an efficient Knuth-Bendix completion procedure based on it. SOUR graphs allow for a maximal structure sharing of terms in rewriting systems. The term representation is a dag representation, except that edges are labelled with equational constraints and variable renamings. The rewrite rules correspond to rewrite edges, the unification problems to unification edges. The Critical Pair and Simplification inferences are recognized as patterns in the graph and are performed as local graph transformations. Our algorithm avoids duplicating term structure while performing inferences, which causes exponential behavior in the standard procedure. This approach gives a basis to design other completion algorithms, such as goal-oriented completion, concurrent completion and group completion procedures.

  2. HIGH EFFICIENCY SYNGAS GENERATION

    Energy Technology Data Exchange (ETDEWEB)

    Robert J. Copeland; Yevgenia Gershanovich; Brian Windecker

    2005-02-01

    This project investigated an efficient and low cost method of auto-thermally reforming natural gas to hydrogen and carbon monoxide. Reforming is the highest cost step in producing products such as methanol and Fisher Tropsch liquids (i.e., gas to liquids); and reducing the cost of reforming is the key to reducing the cost of these products. Steam reforming is expensive because of the high cost of the high nickel alloy reforming tubes (i.e., indirectly fired reforming tubes). Conventional auto-thermal or Partial Oxidation (POX) reforming minimizes the size and cost of the reformers and provides a near optimum mixture of CO and hydrogen. However POX requires pure oxygen, which consumes power and significantly increases the cost to reforming. Our high efficiency process extracts oxygen from low-pressure air with novel oxygen sorbent and transfers the oxygen to a nickel-catalyzed reformer. The syngas is generated at process pressure (typically 20 to 40 bar) without nitrogen dilution and has a 1CO to 2H{sub 2} ratio that is near optimum for the subsequent production of Fisher-Tropsch liquid to liquids and other chemicals (i.e., Gas to Liquids, GTL). Our high process efficiency comes from the way we transfer the oxygen into the reformer. All of the components of the process, except for the oxygen sorbent, are commonly used in commercial practice. A process based on a longlived, regenerable, oxygen transfer sorbent could substantially reduce the cost of natural gas reforming to syngas. Lower cost syngas (CO + 2H{sub 2}) that is the feedstock for GTL would reduce the cost of GTL and for other commercial applications (e.g., methanol, other organic chemicals). The vast gas resources of Alaska's North Slope (ANS) offer more than 22 Tcf of gas and GTL production in this application alone, and could account for as much as 300,000 to 700,000 bpd for 20 to 30+ years. We developed a new sorbent, which is an essential part of the High Efficiency Oxygen Process (HOP). We tested

  3. Automotive fuel efficiency

    International Nuclear Information System (INIS)

    Abelson, P.H.

    1992-01-01

    For at least the remainder of this century, the United States faces a growing dependence on imported oil. Costs are substantial, and they will mount. In June 1992, net imports provided nearly 50% of supplies, and their cost was $4.3 billion. Cost of net imports of motor vehicles and parts amounted to $3.0 billion. The two items combined totaled more than the negative trade balance of $6.6 billion. The light-duty highway fleet alone accounted for 38.2% of U.S. oil consumption in 1988. Correspondingly, the fleet was a substantial emitter of air pollutants - NO x , CO, and nonmethane hydrocarbons. In addition, it was a major source of CO 2 . The twin problems of oil imports and pollution would be ameliorated if the fuel economy if cars and trucks could be improved and their emissions were also reduced. In principle, the mileage of US automobiles could be substantially improved. But on purchasing a car, U.S. buyers rank fuel efficiency eight when making their choice. They are attracted to options that lower mileage. Consumers also tend to prefer large cars over small ones for reasons of safety. Increasingly, buyers are purchasing light trucks and vans that have inferior fuel efficiency. As a result of the above trends, the average mileage of the US automotive fleet has been diminishing. As long as fuel is available at comparatively low prices and there is no federal requirement for better mileage, improvement is unlikely. Moreover, even if improvements were mandated, change would be slow

  4. Efficiency of contactors

    International Nuclear Information System (INIS)

    Orth, D.A.; Graham, F.R.; Holt, D.L.

    1986-01-01

    The Savannah River Plant has two separations plants that began Purex operations in 1954 and 1955 with pump-mix mixer-settlers as contactors to process nuclear fuels. The only changes to the extraction equipment were replacement of most of the mixer-settlers in one plant with larger units in 1959, and the further replacement of the large 1A bank with a bank of rapid-contact centrifugal contactors in 1966. Improved performance of the old units has become highly desirable, and an experimental program is underway. Good contact between the phases, and adequate settling without entrainment of the opposite phase are required for high efficiency operation of the mixer-settlers. Factors that determine efficiency are mixer design, drop size generated, and phase coalescence properties. The original development work and accumulated plant data confirm that the tip speed of a given impeller design determines the throughput capacity and extraction performance. An experimental unit with three full-scale stages has been constructed and is being utilized to test different impeller designs; reduced pumping and better mixing with lower speeds appear to be the key factors for improvement. Decontamination performance of the rapid-contact centrifugal contactors is limited by the number of scrub contacts and the time of contact because of slowly equilibrating fission product species. Where solvent degradation is not a factor, the longer scrub contact of mixer-settlers gives better decontamination than the centrifugals. This kinetic effect can be overcome with long scrub contacts that follow the initial short extraction and short scrub contacts in the centrifugal contactors. A hybrid experimental unit with both rapid contact sections and longer contact scrub sections is under development to establish the degree of improvement that might be attained

  5. Corrosion inhibition efficiency of organic coatings with content of polyaniline phosphate

    Czech Academy of Sciences Publication Activity Database

    Kalendová, A.; Veselý, D.; Stejskal, Jaroslav; Němec, P.

    2009-01-01

    Roč. 13, č. 3 (2009), s. 295-297 ISSN 1432-8917 Institutional research plan: CEZ:AV0Z40500505 Keywords : pigment * coating * corrosion inhibitor * polyaniline * conducting polymer Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.723, year: 2009

  6. Substitution-Inert Trinuclear Platinum Complexes Efficiently Condense/Aggregate Nucleic Acids and Inhibit Enzymatic Activity

    Czech Academy of Sciences Publication Activity Database

    Malina, Jaroslav; Farrell, N. P.; Brabec, Viktor

    2014-01-01

    Roč. 53, č. 47 (2014), s. 12812-12816 ISSN 1433-7851 R&D Projects: GA ČR(CZ) GA13-08273S Institutional support: RVO:68081707 Keywords : DNA condensation * nucleic acids * platinum Subject RIV: BO - Biophysics Impact factor: 11.261, year: 2014

  7. Adenosine triphosphate analogs can efficiently inhibit the Zika virus RNA-dependent RNA polymerase

    Czech Academy of Sciences Publication Activity Database

    Hercík, Kamil; Kozák, Jaroslav; Šála, Michal; Dejmek, Milan; Hřebabecký, Hubert; Zborníková, Eva; Smola, Miroslav; Růžek, Daniel; Nencka, Radim; Bouřa, Evžen

    2017-01-01

    Roč. 137, Jan (2017), s. 131-133 ISSN 0166-3542 R&D Projects: GA ČR GA15-09310S Institutional support: RVO:61388963 ; RVO:60077344 Keywords : hepatitis C virus * borne encephalitis virus * crystal structure Subject RIV: CC - Organic Chemistry OBOR OECD: Organic chemistry Impact factor: 4.271, year: 2016

  8. Efficient inhibition of the formation of joint adhesions by ERK2 small interfering RNAs

    International Nuclear Information System (INIS)

    Li, Fengfeng; Ruan, Hongjiang; Fan, Cunyi; Zeng, Bingfang; Wang, Chunyang; Wang, Xiang

    2010-01-01

    Transforming growth factor-β1 and fibroblast growth factor-2 play very important roles in fibroblast proliferation and collagen expression. These processes lead to the formation of joint adhesions through the SMAD and MAPK pathways, in which extracellular signal-regulated kinase (ERK)2 is considered to be crucial. Based on these theories, we examined the effects of a lentivirus-mediated small interfering RNA (siRNA) targeting ERK2 on the suppression of joint adhesion formation in vivo. The effects were assessed in vivo from different aspects including the adhesion score, histology and joint contracture angle. We found that the adhesions in the ERK2 siRNA group became soft and weak, and were easily stretched. Accordingly, the flexion contracture angles in the ERK2 siRNA group were also reduced (P < 0.05 compared with the control group). The animals appeared healthy, with no signs of impaired wound healing. In conclusion, local delivery of a lentivirus-mediated siRNA targeting ERK2 can ameliorate joint adhesion formation effectively and safely.

  9. Taraxacum officinale dandelion extract efficiently inhibited the breast cancer stem cell proliferation

    OpenAIRE

    Ngu Van Trinh; Nghi Doan-Phuong Dang; Diem Hong Tran; Phuc Van Pham

    2016-01-01

    Background: Breast cancer stem cells (BCSCs) play an important role in breast cancer initiation, metastasis, recurrence, and drug resistance. Therefore, targeting BCSCs is an essential strategy to suppress cancer growth. This study aimed to evaluate the effects of dandelion Taraxacum officinale extracts on BCSC proliferation in vitro in 2D and 3D cell culture platforms. Materials and Methods: The BCSCs were maintained under standard conditions, verified for expression of CD44 and CD24 surface...

  10. Inclusion of the helper lipid dioleoyl-phosphatidylethanolamine in solid lipid nanoparticles inhibits their transfection efficiency

    NARCIS (Netherlands)

    de Jesus, Marcelo B.; Radaic, Allan; Hinrichs, Wouter L J; Ferreira, Carmen V; de Paula, Eneida; Hoekstra, Dirk; Zuhorn, Inge S

    Solid lipid nanoparticles (SLNs) are a promising system for the delivery of lipophilic and hydrophilic drugs. They consist of a solid lipid core that is stabilized by a layer of surfactants. By the incorporation of cationic lipids in the formulation, positively charged SLNs can be generated, that

  11. Allosteric Inhibition Through Core Disruption

    Energy Technology Data Exchange (ETDEWEB)

    Horn, James R.; Shoichet, Brian K. (NWU); (UCSF)

    2010-03-05

    Although inhibitors typically bind pre-formed sites on proteins, it is theoretically possible to inhibit by disrupting the folded structure of a protein or, in the limit, to bind preferentially to the unfolded state. Equilibria defining how such molecules act are well understood, but structural models for such binding are unknown. Two novel inhibitors of {beta}-lactamase were found to destabilize the enzyme at high temperatures, but at lower temperatures showed no preference for destabilized mutant enzymes versus stabilized mutants. X-ray crystal structures showed that both inhibitors bound to a cryptic site in {beta}-lactamase, which the inhibitors themselves created by forcing apart helixes 11 and 12. This opened up a portion of the hydrophobic core of the protein, into which these two inhibitors bind. Although this binding site is 16 {angstrom} from the center of the active site, the conformational changes were transmitted through a sequence of linked motions to a key catalytic residue, Arg244, which in the complex adopts conformations very different from those in catalytically competent enzyme conformations. These structures offer a detailed view of what has heretofore been a theoretical construct, and suggest the possibility for further design against this novel site.

  12. Reduced surround inhibition in musicians.

    Science.gov (United States)

    Shin, Hae-Won; Kang, Suk Y; Hallett, Mark; Sohn, Young H

    2012-06-01

    To investigate whether surround inhibition (SI) in the motor system is altered in professional musicians, we performed a transcranial magnetic stimulation (TMS) study in 10 professional musicians and 15 age-matched healthy non-musicians. TMS was set to be triggered by self-initiated flexion of the index finger at different intervals ranging from 3 to 1,000 ms. Average motor evoked potential (MEP) amplitudes obtained from self-triggered TMS were normalized to average MEPs of the control TMS at rest and expressed as a percentage. Normalized MEP amplitudes of the abductor digiti minimi (ADM) muscles were compared between the musicians and non-musicians with the primary analysis being the intervals between 3 and 80 ms (during the movement). A mixed-design ANOVA revealed a significant difference in normalized ADM MEPs during the index finger flexion between groups, with less SI in the musicians. This study demonstrated that the functional operation of SI is less strong in musicians than non-musicians, perhaps due to practice of movement synergies involving both muscles. Reduced SI, however, could lead susceptible musicians to be prone to develop task-specific dystonia.

  13. Quorum Sensing Inhibition, Relevance to Periodontics

    OpenAIRE

    Yada, Sudheer; Kamalesh, B; Sonwane, Siddharth; Guptha, Indra; Swetha, R K

    2015-01-01

    Quorum sensing helps bacteria to communicate with each other and in coordinating their behavior. Many diseases of human beings, plants, and animals are mediated by quorum sensing. Various approaches are being tried to inhibit this communication to control the diseases caused by bacteria. Periodontal pathogens also communicate through quorum sensing and new approaches to treat periodontal disease using quorum sensing inhibition need to explored.

  14. The pharmacology of visuospatial attention and inhibition

    NARCIS (Netherlands)

    Logemann, H.N.A.

    2013-01-01

    Attention and inhibition are of vital importance in everyday functioning. Problems of attention and inhibition are central to disorders such as Attention Deficit/Hyperactivity Disorder (ADHD). Both bias and disengagement key components of visuospatial attention. Bias refers to neuronal signals that

  15. Inhibition: Mental Control Process or Mental Resource?

    Science.gov (United States)

    Im-Bolter, Nancie; Johnson, Janice; Ling, Daphne; Pascual-Leone, Juan

    2015-01-01

    The current study tested 2 models of inhibition in 45 children with language impairment and 45 children with normally developing language; children were aged 7 to 12 years. Of interest was whether a model of inhibition as a mental-control process (i.e., executive function) or as a mental resource would more accurately reflect the relations among…

  16. Optimal Decision Making in Neural Inhibition Models

    Science.gov (United States)

    van Ravenzwaaij, Don; van der Maas, Han L. J.; Wagenmakers, Eric-Jan

    2012-01-01

    In their influential "Psychological Review" article, Bogacz, Brown, Moehlis, Holmes, and Cohen (2006) discussed optimal decision making as accomplished by the drift diffusion model (DDM). The authors showed that neural inhibition models, such as the leaky competing accumulator model (LCA) and the feedforward inhibition model (FFI), can mimic the…

  17. A Qualitative Approach to Enzyme Inhibition

    Science.gov (United States)

    Waldrop, Grover L.

    2009-01-01

    Most general biochemistry textbooks present enzyme inhibition by showing how the basic Michaelis-Menten parameters K[subscript m] and V[subscript max] are affected mathematically by a particular type of inhibitor. This approach, while mathematically rigorous, does not lend itself to understanding how inhibition patterns are used to determine the…

  18. Contour Detection Operators Based on Surround Inhibition

    NARCIS (Netherlands)

    Grigorescu, Cosmin; Petkov, Nicolai; Westenberg, Michel A.

    2003-01-01

    We propose a biologically motivated computational step, called non-classical receptive field (non-CRF) inhibition, to improve contour detection in images of natural scenes. We augment a Gabor energy operator with non-CRF inhibition. The resulting contour operator responds strongly to isolated lines,

  19. Quorum sensing inhibition, relevance to periodontics.

    Science.gov (United States)

    Yada, Sudheer; Kamalesh, B; Sonwane, Siddharth; Guptha, Indra; Swetha, R K

    2015-01-01

    Quorum sensing helps bacteria to communicate with each other and in coordinating their behavior. Many diseases of human beings, plants, and animals are mediated by quorum sensing. Various approaches are being tried to inhibit this communication to control the diseases caused by bacteria. Periodontal pathogens also communicate through quorum sensing and new approaches to treat periodontal disease using quorum sensing inhibition need to explored.

  20. Somatosensory lateral inhibition processes modulate motor response inhibition - an EEG source localization study.

    Science.gov (United States)

    Friedrich, Julia; Mückschel, Moritz; Beste, Christian

    2017-06-30

    Motor inhibitory control is a central executive function, but only recently the importance of perceptual mechanisms for these processes has been focused. It is elusive whether basic mechanisms governing sensory perception affect motor inhibitory control. We examine whether sensory lateral inhibition (LI) processes modulate motor inhibitory control using a system neurophysiological approach combining EEG signal decomposition with source localization methods in a somatosensory GO/NOGO task. The results show that inter-individual variations in the strength of LI effects predominantly affect processes when information needs to be integrated between cerebral hemispheres. If information needs to be integrated between hemispheres, strong sensory suppression will lead to more impulsive errors. Importantly, the neurophysiological data suggest that not purely perceptual or motor processes are affected. Rather, LI affects the response selection level and modulates processes of stimulus categorization. This is associated with activity modulations in the posterior parietal cortex. The results suggest that when sensory suppression is high and when information needs to be integrated across hemispheres, these processes are less efficient, which likely leads to worse motor inhibitory control. The results show how basis principles modulating perceptual processes affect subsequent motor inhibitory control processes.

  1. Energy-efficient buildings: Does the marketplace work?

    Energy Technology Data Exchange (ETDEWEB)

    Brown, M.A.

    1996-12-31

    For a variety of reasons, U.S. households, businesses, manufacturers, and government agencies all fail to take full advantage of cost-effective, energy-efficiency opportunities. Despite a growing environmental ethic among Americans and a concern for energy independence, consumers in this country are underinvesting in technologies, products, and practices that would cut their energy bills. The result is a large untapped potential for improving energy productivity, economic competitiveness, environmental quality, and energy security. The thesis of this paper is that the marketplace for energy efficiency, in general, is not operating perfectly, and the marketplace for energy-efficient buildings, in particular, is flawed. The reasons for underinvestments in cost-effective, energy efficiency are numerous and complicated. They also vary from sector to sector: the principal causes of energy inefficiencies in agriculture, manufacturing, and transportation are not the same as the causes of inefficiencies in homes and office buildings, although there are some similarities. One of the reasons for these differences is that the structure of marketplace for delivering new technologies and products in each sector differs. Energy-efficiency improvements in the buildings sector is critical to reducing greenhouse gas emissions, since most of the energy consumed in buildings comes from the burning of fossil fuels. This paper therefore begins by describing energy use and energy trends in the U.S. buildings sector. Characteristics of the marketplace for delivering energy efficiency technologies and products are then described in detail, arguing that this marketplace structure significantly inhibits rapid efficiency improvements.

  2. Alternative dosing of dual PI3K and MEK inhibition in cancer therapy.

    Science.gov (United States)

    Jokinen, Elina; Laurila, Niina; Koivunen, Jussi P

    2012-12-21

    -sensitive cell lines showed similar cytotoxicity to continuous PI3K and short (15min) MEK inhibition treatment. Therapy with a dual PI3K and MEK inhibitor combination is more efficient than either inhibitor alone in some NSCLC cell lines. Responses to dual inhibition were not associated with any specific oncogenic genotype and no other predictive factors for dual inhibition were noted. The maximal effect of the dual PI3K and MEK inhibition can be achieved with alternative dosing schedules which are potentially more tolerable clinically.

  3. Do tradeoffs structure antibiotic inhibition, resistance, and resource use among soil-borne Streptomyces?

    Science.gov (United States)

    Schlatter, Daniel C; Kinkel, Linda L

    2015-09-15

    Tradeoffs among competing traits are believed to be crucial to the maintenance of diversity in complex communities. The production of antibiotics to inhibit competitors and resistance to antibiotic inhibition are two traits hypothesized to be critical to microbial fitness in natural habitats, yet data on costs or tradeoffs associated with these traits are limited. In this work we characterized tradeoffs between antibiotic inhibition or resistance capacities and growth efficiencies or niche widths for a broad collection of Streptomyces from soil. Streptomyces isolates tended to have either very little or very high inhibitory capacity. In contrast, Streptomyces isolates were most commonly resistant to antibiotic inhibition by an intermediate number of other isolates. Streptomyces with either very high antibiotic inhibitory or resistance capacities had less efficient growth and utilized a smaller number of resources for growth (smaller niche width) than those with low inhibition or resistance capacities, suggesting tradeoffs between antibiotic inhibitory or resistance and resource use phenotypes. This work suggests that life-history tradeoffs may be crucial to the maintenance of the vast diversity of antibiotic inhibitory and resistance phenotypes found among Streptomyces in natural communities.

  4. Shrew trap efficiency

    DEFF Research Database (Denmark)

    Gambalemoke, Mbalitini; Mukinzi, Itoka; Amundala, Drazo

    2008-01-01

    We investigated the efficiency of four trap types (pitfall, Sherman LFA, Victor snap and Museum Special snap traps) to capture shrews. This experiment was conducted in five inter-riverine forest blocks in the region of Kisangani. The total trapping effort was 6,300, 9,240, 5,280 and 5,460 trap......-nights for the pitfall, Sherman, Victor and Museum Special traps, respectively. In total, we captured 366 shrews. The use of pitfall traps yielded the highest trapping success (4.1) with at least 18 shrew species identified. Trapping success and the number of species collected was lower for the Sherman (0.6, at least 11...... species), Victor (0.6, at least 8 species) and Museum Special (0.5, at least 6 species) traps. Although Crocidura olivieri and C. denti were caught using all four trap types, captures with different trap types did not produce a sample with the same taxonomic composition. In agreement with previous studies...

  5. Impacts of appliance efficiency standards

    Energy Technology Data Exchange (ETDEWEB)

    Hummel, P.; Kesselring, J.

    1992-12-01

    Federal efficiency standards for appliances limit the range of models available on the market. Utility energy efficiency programs often encourage consumers to purchase the most efficient of the remaining options, but more-stringent efficiency standards could have a significant impact on such utility efforts. Using long-run technology scenario forecasting, EPRI-sponsored researchers studied ways in which the interplay of technological change, federal standards, utility efficiency programs, and market forces could affect future energy markets for three major residential end uses: refrigeration, central air conditioning, and water heating. The researchers reached several important conclusions about utility demand-side management efforts. 2 figs., 1 tab.

  6. Correlation between the molecular structure and the inhibiting effect of some benzimidazole derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Niamien, P.M., E-mail: niamienfr@yahoo.fr [Laboratoire de chimie physique, Universite de Cocody-Abidjan, 22 BP 582 Abidjan (Cote d' Ivoire); Essy, F.K.; Trokourey, A.; Yapi, A.; Aka, H.K. [Laboratoire de chimie physique, Universite de Cocody-Abidjan, 22 BP 582 Abidjan (Cote d' Ivoire); Diabate, D. [Laboratoire de chimie physique, Universite de Cocody-Abidjan, 22 BP 582 Abidjan (Cote d' Ivoire); Institut UTINAM-UMR CNRS 6213 Equipe capteurs et membranes 25013 Besancon cedex, 22 BP 582 Abidjan 22 (Cote d' Ivoire)

    2012-09-14

    Quantum chemical parameters of 2-thiobenzylbenzimidazole (TBBI), 2-thiomethylbenzimidazole (TMBI), and 2-mercaptobenzimidazole (MBI) were calculated. The correlation between molecular structure of these compounds and their inhibition efficiency IE (%) against copper corrosion in 1 M HNO{sub 3} was found by considering Density Functional Theory DFT/B3LYP/6-31G (d, p) level. The properties most relevant to their potential action as corrosion inhibitors have been calculated: highest occupied molecular orbital energy (E{sub HOMO}), lowest unoccupied molecular orbital energy (E{sub LUMO}), energy gap ({Delta}E), dipole moment ({mu}) and parameters that provide informations about the chemical reactivity: electronegativity ({chi}), global hardness ({eta}), global softness ({sigma}) and electrophilicity index ({omega}). All calculations have been performed using the Gaussian 03W suite of programs. It was found that theoretical data support experimental results. -- Highlights: Black-Right-Pointing-Pointer Benzimidazole derivatives (TBBI, TMBI, MBI) as corrosion inhibitors of copper in 1 M HNO{sub 3}. Black-Right-Pointing-Pointer The inhibition process evaluated by weight loss indicates that the investigated compounds are good inhibitors of copper. Black-Right-Pointing-Pointer The inhibition efficiency is found to be in the following order: TBBI > TMBI > MBI. Black-Right-Pointing-Pointer The studied molecules adsorbed on the metal surface according to the Langmuir adsorption isotherm. Black-Right-Pointing-Pointer Most of the calculated molecular parameters by DFT/B3LYP/6-31G (d, p) show excellent correlation with the inhibition efficiency.

  7. Efficiency Evaluation of Energy Systems

    CERN Document Server

    Kanoğlu, Mehmet; Dinçer, İbrahim

    2012-01-01

    Efficiency is one of the most frequently used terms in thermodynamics, and it indicates how well an energy conversion or process is accomplished. Efficiency is also one of the most frequently misused terms in thermodynamics and is often a source of misunderstanding. This is because efficiency is often used without being properly defined first. This book intends to provide a comprehensive evaluation of various efficiencies used for energy transfer and conversion systems including steady-flow energy devices (turbines, compressors, pumps, nozzles, heat exchangers, etc.), various power plants, cogeneration plants, and refrigeration systems. The book will cover first-law (energy based) and second-law (exergy based) efficiencies and provide a comprehensive understanding of their implications. It will help minimize the widespread misuse of efficiencies among students and researchers in energy field by using an intuitive and unified approach for defining efficiencies. The book will be particularly useful for a clear ...

  8. Corrosion inhibition of carbon steel in acidic medium by orange peel extract and its main antioxidant compounds

    International Nuclear Information System (INIS)

    M’hiri, Nouha; Veys-Renaux, Delphine; Rocca, Emmanuel; Ioannou, Irina; Boudhrioua, Nourhéne Mihoubi; Ghoul, Mohamed

    2016-01-01

    Highlights: • Catechol and derived functions are responsible for flavonoids antioxidant activity. • Antioxidant activity of adsorbed molecules explains cathodic inhibition. • Orange peel extract inhibition is enhanced by the precipitation of a covering film. - Abstract: Chemical compounds of orange peel extracts were identified and their antioxidant activities were determined. The inhibiting effect on acidic steel corrosion brought by the extract and selected antioxidant compounds (neohesperidin, naringin, ascorbic acid) was evaluated separately by electrochemical methods. Whatever the extract concentration, a significant inhibition is observed, whereas selected antioxidant compounds show only a slight effect. Both electrochemical impedance spectroscopy results and scanning electron microscopy observations after immersion reveal that the inhibiting efficiency of orange peel extract is not only due to the antioxidant activity of its compounds but also to the precipitation of a surface film.

  9. Corrosion inhibition of Eleusine aegyptiaca and Croton rottleri leaf extracts on cast iron surface in 1 M HCl medium

    Energy Technology Data Exchange (ETDEWEB)

    Rajeswari, Velayutham [Department of Chemistry, Periyar University, Salem 636011 (India); Kesavan, Devarayan [Department of Chemistry, Dhirajlal Gandhi College of Technology, Salem 636309 (India); Gopiraman, Mayakrishnan [Department of Chemistry, National Institute of Technology, Tiruchirappalli 620015 (India); Viswanathamurthi, Periasamy, E-mail: viswanathamurthi72@gmail.com [Department of Chemistry, Periyar University, Salem 636011 (India); Poonkuzhali, Kaliyaperumal; Palvannan, Thayumanavan [Department of Bio-Chemistry, Periyar University, Salem 636011 (India)

    2014-09-30

    Graphical abstract: - Highlights: • Eleusine aegyptiaca and Croton rottleri are commonly available, less-toxic and eco-friendly inhibitors for cast iron corrosion. • The active constituents present in extracts adsorbed on the iron surface to inhibit the acidic corrosion. • The higher values of E{sub a} and ΔH{sup *} point out the higher inhibition efficiency noticed for the inhibitors. • Weight loss methods at various temperature and spectral data provides evidence for adsorption mechanism of inhibitors. - Abstract: The adsorption and corrosion inhibition activities of Eleusine aegyptiaca (E. aegyptiaca) and Croton rottleri (C. rottleri) leaf extracts on cast iron corrosion in 1 M hydrochloric acid solution were studied first time by weight loss and electrochemical techniques viz., Tafel polarization and electrochemical impedance spectroscopy. The results obtained from the weight loss and electrochemical methods showed that the inhibition efficiency increased with inhibitor concentrations. It was found that the extracts acted as mixed-type inhibitors. The addition of halide additives (KCl, KBr, and KI) on the inhibition efficiency has also been investigated. The adsorption of the inhibitors on cast iron surface both in the presence and absence of halides follows the Langmuir adsorption isotherm model. The inhibiting nature of the inhibitors was supported by FT-IR, UV–vis, Wide-angle X-ray diffraction and SEM methods.

  10. Corrosion inhibition of Eleusine aegyptiaca and Croton rottleri leaf extracts on cast iron surface in 1 M HCl medium

    International Nuclear Information System (INIS)

    Rajeswari, Velayutham; Kesavan, Devarayan; Gopiraman, Mayakrishnan; Viswanathamurthi, Periasamy; Poonkuzhali, Kaliyaperumal; Palvannan, Thayumanavan

    2014-01-01

    Graphical abstract: - Highlights: • Eleusine aegyptiaca and Croton rottleri are commonly available, less-toxic and eco-friendly inhibitors for cast iron corrosion. • The active constituents present in extracts adsorbed on the iron surface to inhibit the acidic corrosion. • The higher values of E a and ΔH * point out the higher inhibition efficiency noticed for the inhibitors. • Weight loss methods at various temperature and spectral data provides evidence for adsorption mechanism of inhibitors. - Abstract: The adsorption and corrosion inhibition activities of Eleusine aegyptiaca (E. aegyptiaca) and Croton rottleri (C. rottleri) leaf extracts on cast iron corrosion in 1 M hydrochloric acid solution were studied first time by weight loss and electrochemical techniques viz., Tafel polarization and electrochemical impedance spectroscopy. The results obtained from the weight loss and electrochemical methods showed that the inhibition efficiency increased with inhibitor concentrations. It was found that the extracts acted as mixed-type inhibitors. The addition of halide additives (KCl, KBr, and KI) on the inhibition efficiency has also been investigated. The adsorption of the inhibitors on cast iron surface both in the presence and absence of halides follows the Langmuir adsorption isotherm model. The inhibiting nature of the inhibitors was supported by FT-IR, UV–vis, Wide-angle X-ray diffraction and SEM methods

  11. Fear inhibition in high trait anxiety.

    Directory of Open Access Journals (Sweden)

    Merel Kindt

    Full Text Available Trait anxiety is recognized as an individual risk factor for the development of anxiety disorders but the neurobiological mechanisms remain unknown. Here we test whether trait anxiety is associated with impaired fear inhibition utilizing the AX+/BX- conditional discrimination procedure that allows for the independent evaluation of startle fear potentiation and inhibition of fear. Sixty undergraduate students participated in the study--High Trait Anxious: n = 28 and Low Trait Anxious: n = 32. We replicated earlier findings that a transfer of conditioned inhibition for startle responses requires contingency awareness. However, contrary to the fear inhibition hypothesis, our data suggest that high trait anxious individuals show a normal fear inhibition of conditioned startle responding. Only at the cognitive level the high trait anxious individuals showed evidence for impaired inhibitory learning of the threat cue. Together with other findings where impaired fear inhibition was only observed in those PTSD patients who were either high on hyperarousal symptoms or with current anxiety symptoms, we question whether impaired fear inhibition is a biomarker for the development of anxiety disorders.

  12. Encapsulation Efficiency, Oscillatory Rheometry

    Directory of Open Access Journals (Sweden)

    Z. Mohammad Hassani

    2014-01-01

    Full Text Available Nanoliposomes are one of the most important polar lipid-based nanocarriers which can be used for encapsulation of both hydrophilic and hydrophobic active compounds. In this research, nanoliposomes based on lecithin-polyethylene glycol-gamma oryzanol were prepared by using a modified thermal method. Only one melting peak in DSC curve of gamma oryzanol bearing liposomes was observed which could be attributed to co-crystallization of both compounds. The addition of gamma oryzanol, caused to reduce the melting point of 5% (w/v lecithin-based liposome from 207°C to 163.2°C. At high level of lecithin, increasing of liposome particle size (storage at 4°C for two months was more obvious and particle size increased from 61 and 113 to 283 and 384 nanometers, respectively. The encapsulation efficiency of gamma oryzanol increased from 60% to 84.3% with increasing lecithin content. The encapsulation stability of oryzanol in liposome was determined at different concentrations of lecithin 3, 5, 10, 20% (w/v and different storage times (1, 7, 30 and 60 days. In all concentrations, the encapsulation stability slightly decreased during 30 days storage. The scanning electron microscopy (SEM images showed relatively spherical to elliptic particles which indicated to low extent of particles coalescence. The oscillatory rheometry showed that the loss modulus of liposomes were higher than storage modulus and more liquid-like behavior than solid-like behavior. The samples storage at 25°C for one month, showed higher viscoelastic parameters than those having been stored at 4°C which were attributed to higher membrane fluidity at 25°C and their final coalescence.Nanoliposomes are one of the most important polar lipid based nanocarriers which can be used for encapsulation of both hydrophilic and hydrophobic active compounds. In this research, nanoliposomes based on lecithin-polyethylene glycol-gamma oryzanol were prepared by using modified thermal method. Only one

  13. Adsorption properties and inhibition of mild steel corrosion in sulphuric acid solution by ketoconazole: Experimental and theoretical investigation

    Energy Technology Data Exchange (ETDEWEB)

    Obot, I.B. [Department of Chemistry, Faculty of Science, University of Uyo, P.M.B. 1017, Uyo, Akwa Ibom State (Nigeria)], E-mail: proffoime@yahoo.com; Obi-Egbedi, N.O. [Department of Chemistry, University of Ibadan, Ibadan (Nigeria)

    2010-01-15

    Ketoconazole (KCZ) has been evaluated as a corrosion inhibitor for mild steel in aerated 0.1 M H{sub 2}SO{sub 4} by gravimetric method. The effect of KCZ on the corrosion rate was determined at various temperatures and concentrations. The inhibition efficiency increases with increase in inhibitor concentration but decrease with rise in temperature. Adsorption followed the Langmuir isotherm with negative values of {delta}G{sub ads}{sup 0}, suggesting a stable and a spontaneous inhibition process. Quantum chemical approach was further used to calculate some electronic properties of the molecule in order to ascertain any correlation between the inhibitive effect and molecular structure of ketoconazole.

  14. Angiotensin inhibition in heart failure

    Directory of Open Access Journals (Sweden)

    John JV Mcmurray

    2004-03-01

    Full Text Available Survival in patients with heart failure remains very poor, and is worse than that for most common cancers, including bowel cancer in men and breast cancer in women. The renin-angiotensin-aldosterone system (RAAS is not completely blocked by angiotensin-converting enzyme (ACE inhibition. Blockade of the RAAS at the AT1-receptor has the theoretical benefit of more effective blockade of the actions of angiotensin II. ACE inhibitors (ACE-Is prevent the breakdown of bradykinin: this has been blamed for some of the unwanted effects of ACE-Is although bradykinin may have advantageous effects in heart failure. Consequently, ACE-Is and ARBs might be complementary or even additive treatments; recent trials have tested these hypotheses. The Candesartan in Heart failure Assessment of Reduction in Mortality and morbidity (CHARM programme compared the angiotensin receptor blocker (ARB candesartan (target dose 32 mg once daily to placebo in three distinct but complementary populations of patients with symptomatic heart failure. These were: patients with reduced left ventricular ejection fraction (LVEF who were ACE-I-intolerant (CHARM-Alternative; patients with reduced LVEF who were being treated with ACE-Is (CHARM-Added; and patients with preserved left ventricular systolic function (CHARM-Preserved. There were substantial and statistically significant reductions in the primary composite end point (risk of cardiovascular death or hospital admission for heart failure in CHARM-Alternative. This was also the case in CHARM-Added, supporting and extending the findings of Val-HeFT. In CHARM-Preserved, the effect of candesartan on the primary end point did not reach conventional statistical significance though hospital admission for heart failure was reduced significantly with candesartan. In the CHARM-Overall programme there was a statistically borderline reduction in all-cause mortality with a clear reduction in cardiovascular mortality. All-cause mortality was

  15. Angiotensin inhibition in heart failure

    Directory of Open Access Journals (Sweden)

    John JV McMurray

    2004-03-01

    Full Text Available Survival in patients with heart failure remains very poor, and is worse than that for most common cancers, including bowel cancer in men and breast cancer in women. The renin-angiotensin-aldosterone system (RAAS is not completely blocked by angiotensin-converting enzyme (ACE inhibition. Blockade of the RAAS at the AT1-receptor has the theoretical benefit of more effective blockade of the actions of angiotensin II. ACE inhibitors (ACE-Is prevent the breakdown of bradykinin: this has been blamed for some of the unwanted effects of ACE-Is although bradykinin may have advantageous effects in heart failure. Consequently, ACE-Is and ARBs might be complementary or even additive treatments; recent trials have tested these hypotheses.The Candesartan in Heart failure Assessment of Reduction in Mortality and morbidity (CHARM programme compared the angiotensin receptor blocker (ARB candesartan (target dose 32 mg once daily to placebo in three distinct but complementary populations of patients with symptomatic heart failure. These were: patients with reduced left ventricular ejection fraction (LVEF who were ACE-I-intolerant (CHARM-Alternative; patients with reduced LVEF who were being treated with ACE-Is (CHARM-Added; and patients with preserved left ventricular systolic function (CHARM-Preserved.There were substantial and statistically significant reductions in the primary composite end point (risk of cardiovascular death or hospital admission for heart failure in CHARM-Alternative. This was also the case in CHARM-Added, supporting and extending the findings of Val-HeFT. In CHARM-Preserved, the effect of candesartan on the primary end point did not reach conventional statistical significance though hospital admission for heart failure was reduced significantly with candesartan. In the CHARM-Overall programme there was a statistically borderline reduction in all-cause mortality with a clear reduction in cardiovascular mortality. All-cause mortality was

  16. Efficient reactive Brownian dynamics

    Science.gov (United States)

    Donev, Aleksandar; Yang, Chiao-Yu; Kim, Changho

    2018-01-01

    We develop a Split Reactive Brownian Dynamics (SRBD) algorithm for particle simulations of reaction-diffusion systems based on the Doi or volume reactivity model, in which pairs of particles react with a specified Poisson rate if they are closer than a chosen reactive distance. In our Doi model, we ensure that the microscopic reaction rules for various association and dissociation reactions are consistent with detailed balance (time reversibility) at thermodynamic equilibrium. The SRBD algorithm uses Strang splitting in time to separate reaction and diffusion and solves both the diffusion-only and reaction-only subproblems exactly, even at high packing densities. To efficiently process reactions without uncontrolled approximations, SRBD employs an event-driven algorithm that processes reactions in a time-ordered sequence over the duration of the time step. A grid of cells with size larger than all of the reactive distances is used to schedule and process the reactions, but unlike traditional grid-based methods such as reaction-diffusion master equation algorithms, the results of SRBD are statistically independent of the size of the grid used to accelerate the processing of reactions. We use the SRBD algorithm to compute the effective macroscopic reaction rate for both reaction-limited and diffusion-limited irreversible association in three dimensions and compare to existing theoretical predictions at low and moderate densities. We also study long-time tails in the time correlation functions for reversible association at thermodynamic equilibrium and compare to recent theoretical predictions. Finally, we compare different particle and continuum methods on a model exhibiting a Turing-like instability and pattern formation. Our studies reinforce the common finding that microscopic mechanisms and correlations matter for diffusion-limited systems, making continuum and even mesoscopic modeling of such systems difficult or impossible. We also find that for models in which

  17. Adsorption and Inhibitive Properties of Triazolo- pyrimidine Derivatives in Acid Corrosion of Mild Steel

    Directory of Open Access Journals (Sweden)

    K. Parameswari

    2011-01-01

    Full Text Available Inhibitive and adsorption properties of synthesized triazolo- pryimidine derivatives (P1, P2 & P3 for the corrosion of mild steel was investigated using weight loss and electrochemical methods. Inhibition efficiency increased as the concentration of the inhibitor increased but decreased with increase in temperature. The triazolopyrimidines were found to act as adsorption inhibitors for the corrosion of mild steel. The adsorption mechanism of the triazolopyrimidine was found to be physisorption, spontaneous and exothermic. Also the adsorption followed Langmuir adsorption isotherm. polarisation studies showed that the inhibitors behave as cathodic type.

  18. Thioredoxin 80-Activated-Monocytes (TAMs) Inhibit the Replication of Intracellular Pathogens

    DEFF Research Database (Denmark)

    Cortes-Bratti, Ximena; Brasseres, Eugenie; Herrera-Rodriquez, Fabiola

    2011-01-01

    for a role of TAMs in the control of intracellular bacterial infections. As model pathogens we have chosen Listeria monocytogenes and Brucella abortus which replicate in the cytosol and the endoplasmic reticulum respectively. Our data indicate that TAMs efficiently inhibit intracellular growth of both L....... monocytogenes and B. abortus. Further analysis shows that Trx80 activation prevents the escape of GFP-tagged L. monocytogenes into the cytosol, and induces accumulation of the bacteria within the lysosomes. Inhibition of the lysosomal activity by chloroquine treatment resulted in higher replication of bacteria...

  19. USE Efficiency -- Universities and Students for Energy Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Melandri, Daniela

    2010-09-15

    Universities and Student for Energy Efficiency is a European Project within the Intelligent Energy Programme. It intends to create a common stream for energy efficiency systems in university buildings. Universities and students are proposed as shining examples for energy efficiency solutions and behaviour. The Project involves 10 countries and has the aim to improve energy efficiency in university buildings. Students are the main actors of the project together with professors and technicians. To act on students means to act on direct future market players in diffusion of public opinions. A strong communication action supports the succeeding of the action.

  20. Jack bean urease inhibition by crude juices of Allium and Brassica plants. Determination of thiosulfinates.

    Science.gov (United States)

    Olech, Zofia; Zaborska, Wiesława; Kot, Mirosława

    2014-02-15

    The aim of this study was the elucidation of the inhibitory influence of Allium (garlic, onion, leek) and Brassica (cabbage, Brussels sprouts) plants juices, on jack bean urease activity. Concentrations of thiosulfinates, the compounds responsible for the inhibition, were determined in studied materials. The kinetics and mechanism of the inhibitions were investigated. Biphasic, time-dependent courses of the inhibition reactions were observed for all tested Allium and Brussels sprouts from Brassica. The cabbage material caused the monophasic course of the inhibition. In the presence of dithiothreitol, a total reactivation of the inhibited urease proceeded for the tested plants except for the onion. The onion juice modified urease, regained only half of the initial activity. The irreversible contribution was related to the presence of 1-propanethial-S-oxide, cepaenes and zwiebelanes formed in the onion juice. It was found that the thermal processing of the plant juices, results in the decrease of thiosulfinates concentration, as well as the efficiency of urease inhibition. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Improving Gas Flooding Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Reid Grigg; Robert Svec; Zheng Zeng; Alexander Mikhalin; Yi Lin; Guoqiang Yin; Solomon Ampir; Rashid Kassim

    2008-03-31

    This study focuses on laboratory studies with related analytical and numerical models, as well as work with operators for field tests to enhance our understanding of and capabilities for more efficient enhanced oil recovery (EOR). Much of the work has been performed at reservoir conditions. This includes a bubble chamber and several core flood apparatus developed or modified to measure interfacial tension (IFT), critical micelle concentration (CMC), foam durability, surfactant sorption at reservoir conditions, and pressure and temperature effects on foam systems.Carbon dioxide and N{sub 2} systems have been considered, under both miscible and immiscible conditions. The injection of CO2 into brine-saturated sandstone and carbonate core results in brine saturation reduction in the range of 62 to 82% brine in the tests presented in this paper. In each test, over 90% of the reduction occurred with less than 0.5 PV of CO{sub 2} injected, with very little additional brine production after 0.5 PV of CO{sub 2} injected. Adsorption of all considered surfactant is a significant problem. Most of the effect is reversible, but the amount required for foaming is large in terms of volume and cost for all considered surfactants. Some foams increase resistance to the value beyond what is practical in the reservoir. Sandstone, limestone, and dolomite core samples were tested. Dissolution of reservoir rock and/or cement, especially carbonates, under acid conditions of CO2 injection is a potential problem in CO2 injection into geological formations. Another potential change in reservoir injectivity and productivity will be the precipitation of dissolved carbonates as the brine flows and pressure decreases. The results of this report provide methods for determining surfactant sorption and can be used to aid in the determination of surfactant requirements for reservoir use in a CO{sub 2}-foam flood for mobility control. It also provides data to be used to determine rock permeability

  2. Efficient Metropolitan Resource Allocation

    Directory of Open Access Journals (Sweden)

    Richard Arnott

    2016-05-01

    Full Text Available Over the past 30 years Calgary has doubled in size, from a population of 640,645 in 1985 to 1,230,915 in 2015. During that time the City has had five different mayors, hosted the Winter Olympics, and expanded the C-Train from 25 platforms to 45. Calgary’s Metropolitan Area has grown too, with Airdrie, Chestermere, Okotoks and Cochrane growing into full-fledged cities, ripe with inter-urban commuters.* And with changes to provincial legislation in the mid-’90s, rural Rocky View County and the Municipal District of Foothills are now real competitors for residential, commercial and industrial development that in the past would have been considered urban. In this metropolitan system, where people live, their household structure, and their place of work informs the services they need to conduct their daily lives, and directly impacts the spatial character of the City and the broader region. In sum, Metropolitan Calgary is increasingly complex. Calgary and the broader metropolitan area will continue to grow, even with the current economic slowdown. Frictions within Calgary, between the various municipalities in the metropolitan area, and the priorities of other local authorities (such as the School Boards and Alberta Health Services will continue to impact the agendas of local politicians and their ability to answer to the needs of their residents. How resources – whether it is hard infrastructure, affordable housing, classrooms, or hospital beds – are allocated over space and how these resources are funded, directly impacts these relationships. This technical paper provides my perspective as an urban economist on the efficient allocation of resources within a metropolitan system in general, with reference to Calgary where appropriate, and serves as a companion to the previously released “Reflections on Calgary’s Spatial Structure: An Urban Economists Critique of Municipal Planning in Calgary.” It is hoped that the concepts reviewed

  3. Mitigation of Humic Acid Inhibition in Anaerobic Digestion of Cellulose by Addition of Various Salts

    Directory of Open Access Journals (Sweden)

    Samet Azman

    2015-03-01

    Full Text Available Humic compounds are inhibitory to the anaerobic hydrolysis of cellulosic biomass. In this study, the impact of salt addition to mitigate the inhibitory effects of humic compounds was investigated. The experiment was conducted using batch tests to monitor the anaerobic hydrolysis of cellulose in the presence of humic acid. Sodium, potassium, calcium, magnesium and iron salts were tested separately for their efficiency to mitigate humic acid inhibition. All experiments were done under mesophilic conditions (30 °C and at pH 7. Methane production was monitored online, using the Automatic Methane Potential Test System. Methane production, soluble chemical oxygen demand and volatile fatty acid content of the samples were measured to calculate the hydrolysis efficiencies. Addition of magnesium, calcium and iron salts clearly mitigated the inhibitory effects of humic acid and hydrolysis efficiencies reached up to 75%, 65% and 72%, respectively, which were similar to control experiments. Conversely, potassium and sodium salts addition did not mitigate the inhibition and hydrolysis efficiencies were found to be less than 40%. Mitigation of humic acid inhibition via salt addition was also validated by inductively coupled plasma atomic emission spectroscopy analyses, which showed the binding capacity of different cations to humic acid.

  4. Product inhibition of five Hypocrea jecorina cellulases

    DEFF Research Database (Denmark)

    Murphy, Leigh; Westh, Peter; Bohlin, Christina

    2013-01-01

    Product inhibition of cellulolytic enzymes has been deemed a critical factor in the industrial saccharification of cellulosic biomass. Several investigations have addressed this problem using crude enzyme preparations or commercial (mixed) cellulase products, but quantitative information...

  5. Single-molecule theory of enzymatic inhibition.

    Science.gov (United States)

    Robin, Tal; Reuveni, Shlomi; Urbakh, Michael

    2018-02-22

    The classical theory of enzymatic inhibition takes a deterministic, bulk based approach to quantitatively describe how inhibitors affect the progression of enzymatic reactions. Catalysis at the single-enzyme level is, however, inherently stochastic which could lead to strong deviations from classical predictions. To explore this, we take the single-enzyme perspective and rebuild the theory of enzymatic inhibition from the bottom up. We find that accounting for multi-conformational enzyme structure and intrinsic randomness should strongly change our view on the uncompetitive and mixed modes of inhibition. There, stochastic fluctuations at the single-enzyme level could make inhibitors act as activators; and we state-in terms of experimentally measurable quantities-a mathematical condition for the emergence of this surprising phenomenon. Our findings could explain why certain molecules that inhibit enzymatic activity when substrate concentrations are high, elicit a non-monotonic dose response when substrate concentrations are low.

  6. Socially-Efficient Tax Reforms

    OpenAIRE

    Duclos, Jean-Yves; Makdissi, Paul; Wodon, Quentin

    2002-01-01

    We propose graphical methods to determine whether commodity-tax changes are "socially efficient", in the sense of improving social welfare or decreasing poverty for large classes of social welfare and poverty indices. We also derive estimators of critical poverty lines and economic efficiency ratios which can be used to characterize socially-efficient tax reforms. The statistical properties of the various estimators are derived in order to make the method implementable using survey data. The ...

  7. Energy efficiency policies and measures

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    This document makes a review of the energy efficiency and demand side management (DSM) policies and measures in European Union countries and Norway in 1999: institutional changes, measures and programmes, budget, taxation, existence of a national DSM programme, national budgets for DSM programmes, electricity pricing: energy/environment tax, national efficiency standards and regulation for new electrical appliances, implementation of Commission directives, efficiency requirements, labelling, fiscal and economic incentives. (J.S.)

  8. Stochastic efficiency: five case studies

    International Nuclear Information System (INIS)

    Proesmans, Karel; Broeck, Christian Van den

    2015-01-01

    Stochastic efficiency is evaluated in five case studies: driven Brownian motion, effusion with a thermo-chemical and thermo-velocity gradient, a quantum dot and a model for information to work conversion. The salient features of stochastic efficiency, including the maximum of the large deviation function at the reversible efficiency, are reproduced. The approach to and extrapolation into the asymptotic time regime are documented. (paper)

  9. Efficiency, sustainability and global warming

    International Nuclear Information System (INIS)

    Woodward, Richard T.; Bishop, Richard C.

    1995-01-01

    Economic analyses of global warming have typically been grounded in the theory of economic efficiency. Such analyses may be inappropriate because many of the underlying concerns about climate change are rooted not in efficiency, but in the intergenerational allocation of economic endowments. A simple economic model is developed which demonstrates that an efficient economy is not necessarily a sustainable economy. This result leads directly to questions about the policy relevance of several economic studies of the issue. We then consider policy alternatives to address global warming in the context of economies with the dual objectives of efficiency and sustainability, with particular attention to carbon-based taxes

  10. From energy efficiency towards resource efficiency within the Ecodesign Directive

    DEFF Research Database (Denmark)

    Bundgaard, Anja Marie; Mosgaard, Mette; Remmen, Arne

    2017-01-01

    The article examines the integration of resource efficiency into the European Ecodesign Directive. The purpose is to analyse the processes and stakeholder interactions, which formed the basis for integrating resource efficiency requirements into the implementing measure for vacuum cleaners and th...

  11. Inhibition of 2-methoxyestradiol glucuronidation by probenecid.

    Science.gov (United States)

    Qian, Yuli; Sherbini, Ahmad; Matin, Bahar; Zhao, Yanli; Castellot, John; Greenblatt, David J

    2015-11-01

    2-Methoxyestradiol (2ME2), a metabolite of estradiol, has antitumour activity in vitro. However, potential clinical applicability has been limited by low oral bioavailability. Probenecid was evaluated in vitro as an inhibitor of 2ME2 glucuronidation for purposes of enhancing 2ME2 oral bioavailability. Human liver microsomes were used to determine kinetic parameters for transformation of 2ME2 to its glucuronide metabolites (M1, M2) and inhibition of the reactions by probenecid. M1 and M2 formation from 2ME2 proceeded with features of substrate inhibition. Probenecid inhibited metabolite formation, with mean inhibition constant (Ki ) values of 0.9 and 2.6 mM, respectively. Inhibition was reversible, with mixed competitive-non-competitive characteristics. The Ki values for probenecid inhibition of 2ME2 glucuronide formation, when compared to maximum probenecid plasma concentrations anticipated clinically, indicate that probenecid co-administration has the potential to augment systemic plasma levels of 2ME2 after oral dosage in humans. © 2015 Royal Pharmaceutical Society.

  12. Effects of Inhibition Conditions on Anammox process

    Science.gov (United States)

    Xie, Haitao; Ji, Dandan; Zang, Lihua

    2017-12-01

    Anaerobic ammonium oxidation (Anammox) is a very suitable process for the treatment of nitrogen-rich wastewater, which is a promising new biological nitrogen removal process, and has a good application prospects. However, the Anammox process is inhibited by many factors, which hinders the process improvement and the application of the Anammox process. Such as organic,temperature,salts,heavy metals, phosphates, sulfides, pH and other inhibitors are usually present in practical applications. We have reviewed the previous researches on the inhibition of Anammox processes. The effect of the substrate on the anaerobic oxide is mainly caused by free ammonia or nitrite nitrogen. Most heavy metals inhibit Anammox growth and activity. The inhibition of organic matter depends on the content of organic matter and species. High salinity inhibits Anammox activity. Dissolved oxygen allows the flora to be in a balanced state. The optimum pH and temperature, as well as other factors, can provide a good growth environment for Anammox. The knowledge of inhibition on Anammox will help prevent the application and improvement of the Anammox process.

  13. Inhibition of Heme Peroxidases by Melamine

    Directory of Open Access Journals (Sweden)

    Pattaraporn Vanachayangkul

    2012-01-01

    Full Text Available In 2008 melamine-contaminated infant formula and dairy products in China led to over 50,000 hospitalizations of children due to renal injuries. In North America during 2007 and in Asia during 2004, melamine-contaminated pet food products resulted in numerous pet deaths due to renal failure. Animal studies have confirmed the potent renal toxicity of melamine combined with cyanuric acid. We showed previously that the solubility of melamine cyanurate is low at physiologic pH and ionic strength, provoking us to speculate how toxic levels of these compounds could be transported through the circulation without crystallizing until passing into the renal filtrate. We hypothesized that melamine might be sequestered by heme proteins, which could interfere with heme enzyme activity. Four heme peroxidase enzymes were selected for study: horseradish peroxidase (HRP, lactoperoxidase (LPO, and cyclooxygenase-1 and -2 (COX-1 and -2. Melamine exhibited noncompetitive inhibition of HRP (9.5±0.7mM, and LPO showed a mixed model of inhibition (14.5±4.7mM. The inhibition of HRP and LPO was confirmed using a chemiluminescent peroxidase assay. Melamine also exhibited COX-1 inhibition, but inhibition of COX-2 was not detected. Thus, our results demonstrate that melamine inhibits the activity of three heme peroxidases.

  14. Inhibition in the Human Auditory Cortex.

    Directory of Open Access Journals (Sweden)

    Koji Inui

    Full Text Available Despite their indispensable roles in sensory processing, little is known about inhibitory interneurons in humans. Inhibitory postsynaptic potentials cannot be recorded non-invasively, at least in a pure form, in humans. We herein sought to clarify whether prepulse inhibition (PPI in the auditory cortex reflected inhibition via interneurons using magnetoencephalography. An abrupt increase in sound pressure by 10 dB in a continuous sound was used to evoke the test response, and PPI was observed by inserting a weak (5 dB increase for 1 ms prepulse. The time course of the inhibition evaluated by prepulses presented at 10-800 ms before the test stimulus showed at least two temporally distinct inhibitions peaking at approximately 20-60 and 600 ms that presumably reflected IPSPs by fast spiking, parvalbumin-positive cells and somatostatin-positive, Martinotti cells, respectively. In another experiment, we confirmed that the degree of the inhibition depended on the strength of the prepulse, but not on the amplitude of the prepulse-evoked cortical response, indicating that the prepulse-evoked excitatory response and prepulse-evoked inhibition reflected activation in two different pathways. Although many diseases such as schizophrenia may involve deficits in the inhibitory system, we do not have appropriate methods to evaluate them; therefore, the easy and non-invasive method described herein may be clinically useful.

  15. Shifts in metabolic hydrogen sinks in the methanogenesis-inhibited ruminal fermentation: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Emilio M. Ungerfeld

    2015-02-01

    Full Text Available Maximizing the flow of metabolic hydrogen ([H] in the rumen away from CH4 and towards volatile fatty acids (VFA would increase the efficiency of ruminant production and decrease its environmental impact. The objectives of this meta-analysis were: i To quantify shifts in metabolic hydrogen sinks when inhibiting ruminal methanogenesis in vitro; and ii To understand the variation in shifts of metabolic hydrogen sinks among experiments and between batch and continuous cultures systems when methanogenesis is inhibited. Batch (28 experiments, N=193 and continuous (16 experiments, N=79 culture databases of experiments with at least 50% inhibition in CH4 production were compiled. Inhibiting methanogenesis generally resulted in less fermentation and digestion in most batch culture, but not in most continuous culture, experiments. Inhibiting CH4 production in batch cultures resulted in redirection of metabolic hydrogen towards propionate and H2 but not butyrate. In continuous cultures, there was no overall metabolic hydrogen redirection towards propionate or butyrate, and H2 as a proportion of metabolic hydrogen spared from CH4 production was numerically smaller compared to batch cultures. Dihydrogen accumulation was affected by type of substrate and methanogenesis inhibitor, with highly fermentable substrates resulting in greater redirection of metabolic hydrogen towards H2 when inhibiting methanogenesis, and some oils causing small or no H2 accumulation. In both batch and continuous culture, there was a decrease in metabolic hydrogen recovered as the sum of propionate, butyrate, CH4 and H2 when inhibiting methanogenesis, and it is speculated that as CH4 production decreases metabolic hydrogen could be increasingly incorporated into formate, microbial biomass, and, perhaps, reductive acetogenesis in continuous cultures. Energetic benefits of inhibiting methanogenesis depended on the inhibitor and its concentration and on the in vitro system.

  16. Inhibition of ethylene production by putrescine alleviates aluminium-induced root inhibition in wheat plants

    OpenAIRE

    Yu, Yan; Jin, Chongwei; Sun, Chengliang; Wang, Jinghong; Ye, Yiquan; Zhou, Weiwei; Lu, Lingli; Lin, Xianyong

    2016-01-01

    Inhibition of root elongation is one of the most distinct symptoms of aluminium (Al) toxicity. Although putrescine (Put) has been identified as an important signaling molecule involved in Al tolerance, it is yet unknown how Put mitigates Al-induced root inhibition. Here, the possible mechanism was investigated by using two wheat genotypes differing in Al resistance: Al-tolerant Xi Aimai-1 and Al-sensitive Yangmai-5. Aluminium caused more root inhibition in Yangmai-5 and increased ethylene pro...

  17. Somatodendritic Expression of JAM2 Inhibits Oligodendrocyte Myelination.

    Science.gov (United States)

    Redmond, Stephanie A; Mei, Feng; Eshed-Eisenbach, Yael; Osso, Lindsay A; Leshkowitz, Dena; Shen, Yun-An A; Kay, Jeremy N; Aurrand-Lions, Michel; Lyons, David A; Peles, Elior; Chan, Jonah R

    2016-08-17

    Myelination occurs selectively around neuronal axons to increase the efficiency and velocity of action potentials. While oligodendrocytes are capable of myelinating permissive structures in the absence of molecular cues, structurally permissive neuronal somata and dendrites remain unmyelinated. Utilizing a purified spinal cord neuron-oligodendrocyte myelinating co-culture system, we demonstrate that disruption of dynamic neuron-oligodendrocyte signaling by chemical cross-linking results in aberrant myelination of the somatodendritic compartment of neurons. We hypothesize that an inhibitory somatodendritic cue is necessary to prevent non-axonal myelination. Using next-generation sequencing and candidate profiling, we identify neuronal junction adhesion molecule 2 (JAM2) as an inhibitory myelin-guidance molecule. Taken together, our results demonstrate that the somatodendritic compartment directly inhibits myelination and suggest a model in which broadly indiscriminate myelination is tailored by inhibitory signaling to meet local myelination requirements. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Up-regulation of reciprocal inhibition by explosive strength training

    DEFF Research Database (Denmark)

    Geertsen, Svend Sparre; Jensen, Jesper Lundbye; Nielsen, Jens Bo

    At the onset of dorsiflexion disynaptic reciprocal inhibition (DRI) of soleus motoneurones is increased in order to prevent activation of the antagonistic plantarflexors. This is caused by descending facilitation of transmission in the DRI pathway. Since the risk of eliciting stretch reflexes...... in the ankle plantarflexors at the onset of dorsiflexion is larger the quicker the movement, we hypothesized that DRI may be up-regulated when subjects are trained to perform dorsiflexion movements as quickly as possible.   For this purpose, 15 healthy human subjects (7 male, 8 female) with an average age...... by 6% before the training and by 22% after the training, which was a statistically significant difference (pregulated in healthy subjects following explosive strength training in order to ensure efficient suppression of the antagonist...

  19. Inhibition of Sodium Benzoate on Stainless Steel in Tropical Seawater

    International Nuclear Information System (INIS)

    Seoh, S. Y.; Senin, H. B.; Nik, W. N. Wan; Amin, M. M.

    2007-01-01

    The inhibition of sodium benzoate for stainless steel controlling corrosion was studied in seawater at room temperature. Three sets of sample have been immersed in seawater containing sodium benzoate with the concentrations of 0.3M, 0.6M and 1.0M respectively. One set of sample has been immersed in seawater without adding any sodium benzoate. It was found that the highest corrosion rate was observed for the stainless steel with no inhibitor was added to the seawater. As the concentration of sodium benzoate being increased, the corrosion rate is decreases. Results show that by the addition of 1.0M of sodium benzoate in seawater samples, it giving ≥ 90% efficiencies

  20. Computational and electrochemical investigation for corrosion inhibition of nickel in molar sulfuric acid by dihydrazide derivatives. Part II

    Directory of Open Access Journals (Sweden)

    H. Shokry

    2017-05-01

    Full Text Available Correlation of the efficiency of some dihydrazide derivatives, namely malonic acid (MAD, succinic acid (SAD and adipic acid (AAD dihydrazide, against the corrosion of nickel in 1 M sulfuric acid solution is discussed using electrochemical polarization method and quantum chemical calculations based on the ab initio method. The quantum chemical parameters calculated are, the highest occupied molecular orbital (HOMO, the lowest unoccupied molecular orbital (LUMO, the gap energy (ΔE, the dipole moment (μ, the softness (σ and the total energy (TE. The relations between the inhibition efficiency and some quantum parameters are discussed and correlations are proposed. The protection efficiencies of these compounds showed a certain relationship to Mulliken atomic charges and Fukui indices. Dihydrazide inhibitor (AAD exhibited the highest inhibition efficiency.

  1. Inhibition of human natural killer (NK) cytotoxicity by Candida albicans

    International Nuclear Information System (INIS)

    Zunino, S.; Hudig, D.

    1986-01-01

    Experiments were initiated to determine whether human NK cells are cytotoxic to C. albicans with similar activity observed for mouse NK cells against the yeast Paracoccidiodes brasiliensis. In 48 hour assays using limiting dilutions of C. albicans, strain 3153A, mononuclear leukocytes with NK activity had only marginal effects on yeast outgrowth, whereas granulocytes killed most of the yeast. However, these yeast were able to block NK activity in 4 hr 51 Cr release assays with K562 cells, at yeast to K562 ratios of 10:1 and 100:1. Yeast pretreated with the serum of the majority of donors blocked the NK activity more than untreated yeast. Two of the 7 donors did not enhance NK inhibition after pretreatment of the yeast with their serum. Serum antibody to C. albicans and complement consumption by the yeast correlated with the relative efficiency of NK inhibition for most donors. This report suggests that there may be in vivo interactions between NK cells of the immune system and opportunistic fungal pathogens, which may compromise NK cell function

  2. Linear ubiquitin chain induces apoptosis and inhibits tumor growth.

    Science.gov (United States)

    Qin, Zhoushuai; Jiang, Wandong; Wang, Guifen; Sun, Ying; Xiao, Wei

    2018-01-01

    Ubiquitination of proliferating cell nuclear antigen (PCNA) plays an important role in DNA damage response. Ectopic expression of PCNA fused at either terminus with ubiquitin (Ub) lacking two C-terminal glycine residues induces translesion DNA synthesis which resembles synthesis mediated by PCNA monoubiquitination. PCNA fused with Ub containing the C-terminal Gly residues at the C-terminus can be further polyubiquitinated in a Gly-dependent manner, which inhibits cell proliferation and induces ATR-dependent replication checkpoint. In this study, we surprisingly found that PCNA fused to a head-to-tail linear Ub chain induces apoptosis in a Ub chain length-dependent manner. Further investigation revealed that the apoptotic effect is actually induced by the linear Ub chain independently from PCNA, as the Ub chain fused to GFP or an epitope tag still efficiently induces apoptosis. It is revealed that the artificial linear Ub chain differs from endogenously encoded linear Ub chains in that its Ubs contain a Ub-G76S substitution, making the Ub chain resistant to cleavage by deubiquitination enzymes. We demonstrated in this study that ectopic expression of the artificial Ub chain alone in cultured human cancer cells is sufficient to inhibit tumor growth in a xenograft mouse model, making the linear Ub chain a putative anti-cancer agent.

  3. Discovery of New Classes of Compounds that Reactivate Acetylcholinesterase Inhibited by Organophosphates

    Energy Technology Data Exchange (ETDEWEB)

    Katz, Francine S. [Department of Medicine/Division of Experimental Therapeutics, Columbia University Medical Center, 630 W. 168th Street New York NY 10032 USA; Pecic, Stevan [Department of Medicine/Division of Experimental Therapeutics, Columbia University Medical Center, 630 W. 168th Street New York NY 10032 USA; Tran, Timothy H. [Department of Biological Sciences, Columbia University, 1212 Amsterdam Avenue New York NY 10027 USA; Trakht, Ilya [Department of Medicine/Division of Experimental Therapeutics, Columbia University Medical Center, 630 W. 168th Street New York NY 10032 USA; Schneider, Laura [Department of Medicine/Division of Experimental Therapeutics, Columbia University Medical Center, 630 W. 168th Street New York NY 10032 USA; Zhu, Zhengxiang [Department of Medicine/Division of Experimental Therapeutics, Columbia University Medical Center, 630 W. 168th Street New York NY 10032 USA; Ton-That, Long [Department of Medicine/Division of Experimental Therapeutics, Columbia University Medical Center, 630 W. 168th Street New York NY 10032 USA; Luzac, Michal [Department of Medicine/Division of Experimental Therapeutics, Columbia University Medical Center, 630 W. 168th Street New York NY 10032 USA; Zlatanic, Viktor [Department of Medicine/Division of Experimental Therapeutics, Columbia University Medical Center, 630 W. 168th Street New York NY 10032 USA; Damera, Shivani [Department of Medicine/Division of Experimental Therapeutics, Columbia University Medical Center, 630 W. 168th Street New York NY 10032 USA; Macdonald, Joanne [Department of Medicine/Division of Experimental Therapeutics, Columbia University Medical Center, 630 W. 168th Street New York NY 10032 USA; Genecology Research Centre, Inflammation and Healing Research Cluster, School of Science and Engineering, University of the Sunshine Coast, 90 Sippy Downs Drive Sippy Downs QLD 4556 Australia; Landry, Donald W. [Department of Medicine/Division of Experimental Therapeutics, Columbia University Medical Center, 630 W. 168th Street New York NY 10032 USA; Tong, Liang [Department of Biological Sciences, Columbia University, 1212 Amsterdam Avenue New York NY 10027 USA; Stojanovic, Milan N. [Department of Medicine/Division of Experimental Therapeutics, Columbia University Medical Center, 630 W. 168th Street New York NY 10032 USA; Departments of Biomedical Engineering and Systems Biology, Columbia University, 630 W. 168th street New York NY 10032 USA

    2015-09-09

    Acetylcholinesterase (AChE) that has been covalently inhibited by organophosphate compounds (OPCs), such as nerve agents and pesticides, has traditionally been reactivated by using nucleophilic oximes. There is, however, a clearly recognized need for new classes of compounds with the ability to reactivate inhibited AChE with improved in vivo efficacy. Here we describe our discovery of new functional groups—Mannich phenols and general bases—that are capable of reactivating OPC-inhibited AChE more efficiently than standard oximes and we describe the cooperative mechanism by which these functionalities are delivered to the active site. These discoveries, supported by preliminary in vivo results and crystallographic data, significantly broaden the available approaches for reactivation of AChE.

  4. Mathematics anxiety and working memory: support for the existence of a deficient inhibition mechanism.

    Science.gov (United States)

    Hopko, D R; Ashcraft, M H; Gute, J; Ruggiero, K J; Lewis, C

    1998-01-01

    A current theory of anxiety effects in cognition claims that anxiety disrupts normal processing within the working memory system. We examined this theory in the context of a reading task, for participants who were high or low in assessed mathematics anxiety. The task was designed to measure the ability to inhibit attention to distracting information and the effects of this ability on explicit memory performance. The results suggested that math-anxious individuals have a deficient inhibition mechanism whereby working memory resources are consumed by task-irrelevant distracters. A consequence of this deficiency was that explicit memory performance was poorer for high-anxious individuals. Based on these results, the recommendation is made that Eysenck and Calvo's (1992) processing efficiency theory be integrated with Connelly, Hasher, and Zack's (1991) inhibition theory to portray more comprehensively the relation between anxiety and performance.

  5. Producing energy efficiently; Energieeffizient produzieren

    Energy Technology Data Exchange (ETDEWEB)

    Blass, H.W.; Schumacher, M.; Coy, C; Pfister, J.; Finkbeiner, M.; Kuehnle, J.; Kiel, E.; Duerrschmidt, R.; Diede, J.; Scheffels, G.; Kranz, H.; Simon, J.; Diebold, K.; Koch, H.R.; Lehnhardt, M.

    2008-04-07

    Producing energy efficiently means saving much energy and money. Drives are responsible for the accounting of power for companies. The fair shows examples on the complete field of producing sector, hits the advantages of heat recovery and an efficient cooling. (GL)

  6. Market Competition and Efficient Cooperation

    NARCIS (Netherlands)

    Brandts, J.; Riedl, Arno

    2016-01-01

    We find that in market-partners, market experience has adverse effects on the efficiency of cooperation on both market-winner and market-loser pairs. In market-strangers, pairs of market-winners manage to cooperate more efficiently. These results indicate that it is not market experience per se that

  7. Motor-operated gearbox efficiency

    Energy Technology Data Exchange (ETDEWEB)

    DeWall, K.G.; Watkins, J.C.; Bramwell, D. [Idaho National Engineering Lab., Idaho Falls, ID (United States); Weidenhamer, G.H.

    1996-12-01

    Researchers at the Idaho National Engineering Laboratory recently conducted tests investigating the operating efficiency of the power train (gearbox) in motor-operators typically used in nuclear power plants to power motor-operated valves. Actual efficiency ratios were determined from in-line measurements of electric motor torque (input to the operator gearbox) and valve stem torque (output from the gearbox) while the operators were subjected to gradually increasing loads until the electric motor stalled. The testing included parametric studies under reduced voltage and elevated temperature conditions. As part of the analysis of the results, the authors compared efficiency values determined from testing to the values published by the operator manufacturer and typically used by the industry in calculations for estimating motor-operator capabilities. The operators they tested under load ran at efficiencies lower than the running efficiency (typically 50%) published by the operator manufacturer.

  8. Motor-operator gearbox efficiency

    International Nuclear Information System (INIS)

    DeWall, K.G.; Watkins, J.C.; Bramwell, D.

    1996-01-01

    Researchers at the Idaho National Engineering Laboratory recently conducted tests investigating the operating efficiency of the power train (gearbox) in motor-operators typically used in nuclear power plants to power motor-operated valves. Actual efficiency ratios were determined from in-line measurements of electric motor torque (input to the operator gearbox) and valve stem torque (output from the gearbox) while the operators were subjected to gradually increasing loads until the electric motor stalled. The testing included parametric studies under reduced voltage and elevated temperature conditions. As part of the analysis of the results, we compared efficiency values determined from testing to the values published by the operator manufacturer and typically used by the industry in calculations for estimating motor-operator capabilities. The operators we tested under load ran at efficiencies lower than the running efficiency (typically 50%) published by the operator manufacturer

  9. Gold, currencies and market efficiency

    Science.gov (United States)

    Kristoufek, Ladislav; Vosvrda, Miloslav

    2016-05-01

    Gold and currency markets form a unique pair with specific interactions and dynamics. We focus on the efficiency ranking of gold markets with respect to the currency of purchase. By utilizing the Efficiency Index (EI) based on fractal dimension, approximate entropy and long-term memory on a wide portfolio of 142 gold price series for different currencies, we construct the efficiency ranking based on the extended EI methodology we provide. Rather unexpected results are uncovered as the gold prices in major currencies lay among the least efficient ones whereas very minor currencies are among the most efficient ones. We argue that such counterintuitive results can be partly attributed to a unique period of examination (2011-2014) characteristic by quantitative easing and rather unorthodox monetary policies together with the investigated illegal collusion of major foreign exchange market participants, as well as some other factors discussed in some detail.

  10. Motor-operated gearbox efficiency

    International Nuclear Information System (INIS)

    DeWall, K.G.; Watkins, J.C.; Bramwell, D.; Weidenhamer, G.H.

    1996-01-01

    Researchers at the Idaho National Engineering Laboratory recently conducted tests investigating the operating efficiency of the power train (gearbox) in motor-operators typically used in nuclear power plants to power motor-operated valves. Actual efficiency ratios were determined from in-line measurements of electric motor torque (input to the operator gearbox) and valve stem torque (output from the gearbox) while the operators were subjected to gradually increasing loads until the electric motor stalled. The testing included parametric studies under reduced voltage and elevated temperature conditions. As part of the analysis of the results, the authors compared efficiency values determined from testing to the values published by the operator manufacturer and typically used by the industry in calculations for estimating motor-operator capabilities. The operators they tested under load ran at efficiencies lower than the running efficiency (typically 50%) published by the operator manufacturer

  11. Corrosion inhibition of nickel in H2SO4 solution by alanine

    International Nuclear Information System (INIS)

    Hamed, E.; Abd El-REhim, S.S.; El-Shahat, M.F.; Shaltot, A.M.

    2012-01-01

    Highlights: ► Corrosion of Ni in 1 M H 2 SO 4 in the absence and the presence of alanine. ► Alanine acts as a moderate mixed type inhibitor. ► Physical adsorption of alanine and formation of protective film are on Ni surface. ► Addition of KI improves the inhibition efficiency (synergistic effect). ► EFM technique is in reasonably good agreement with the different techniques used. - Abstract: The effect of alanine, as a safe inhibitor, was studied by measuring the corrosion of Ni in aerated and stagnant 1 M H 2 SO 4 solution (pH ∼0.2). Measurements were performed under various conditions using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and the new electrochemical frequency modulation (EFM) methods. The obtained results showed that the addition of alanine alone gives a moderate inhibition and acts as an anodic-type inhibitor. The inhibition is due to physical adsorption of alanine on the metal surface. The inhibition efficiency enhances with increasing alanine concentration and immersion time but decreases with rise in temperature. The apparent activation energy, E a , is higher in the presence than in the absence of alanine. Addition of I − ions greatly improves the inhibition efficiency of alanine. The synergistic effect is due to enhanced adsorption of alanine cations by chemisorbed I − anions on the metal surface. The results obtained from polarization, EIS and EFM techniques are in good agreement indicating that EFM method can be used successfully for monitoring corrosion rate of Ni in H 2 SO 4 solution with and without alanine.

  12. Corrosion inhibition of copper in neutral chloride media by a novel derivative of 1,2,4-triazole

    OpenAIRE

    Khiati, Zoulicka; Othman, A.A.; Sanchez-Moreno, M.; Bernard, Marie-Claude; Joiret, Suzanne; Sutter, Eliane; Vivier, Vincent

    2011-01-01

    International audience; The efficiency of a new corrosion inhibitor, the bis-(4-amino-5-mercapto-1,2,4-triazol-3-yl)-butane (BAMTB), on copper was investigated in an aerated 3% NaCl solution using various techniques. Voltammetry, chronopotentiometry and electrochemical impedance spectroscopy (EIS) were performed to evaluate the inhibition efficiency of BAMTB. The surface layers were also characterized by Raman micro-spectroscopy and by scanning electron microscopy (SEM) coupled with energy di...

  13. Application of gold nanoparticles for improved drug efficiency

    Science.gov (United States)

    Shittu, K. O.; Bankole, M. T.; Abdulkareem, A. S.; Abubakre, O. K.; Ubaka, A. U.

    2017-09-01

    Due to increasing resistance of microorganisms towards current antibiotics, there is a need for new or enhanced antibiotics. Nanotechnology is a technology that enhances the use of gold nanoparticles (AuNP) in area of medical applications, especially as a drug carrier for targeted drug delivery. In this research, AuNPs was synthesized using biological method via bioreduction of Piper guineense aqueous leaf extract on tetra gold chloride, characterized using UV-Vis spectrophometer, DLS, TEM/EDS and FTIR. The synthesized AuNPs was covalently functionalized with polyethylene glycol and encapsulated with Lincomycin and in vitro dissolution methods was used to evaluate the potential performance of the formulated nanodrug. The nanodrug has highest release efficiency at the 9th minutes (23.4 mg ml-1 for 40 °C) and (29.5 mg ml-1 for 60 °C) compared with the non-nanodrug. The antibacterial potential of the nanodrug was seen on the gram-positive bacteria of Staphylococcus aureus and Streptococcus pyogenes with highest inhibitions of 18 mm (at 40 °C) and 16 mm (at 60 °C) for S. aureus, and 16 mm for S. pyogenes (both at 40 °C and 60 °C). The bacteria growth inhibition continued and lasted for 15 min, while that of non-nanodrug lasted for 9 min with lesser growth inhibition compared to the formulated nanodrug. This work shows that the presence of the AuNPs increased the release efficiency of lincomycin even at a lower concentration and also bacteria growth inhibition thereby suggesting the effectiveness of the nanodrug formulation.

  14. Inhibition of MHC class I is a virulence factor in herpes simplex virus infection of mice.

    Directory of Open Access Journals (Sweden)

    2005-09-01

    Full Text Available Herpes simplex virus (HSV has a number of genes devoted to immune evasion. One such gene, ICP47, binds to the transporter associated with antigen presentation (TAP 1/2 thereby preventing transport of viral peptides into the endoplasmic reticulum, loading of peptides onto nascent major histocompatibility complex (MHC class I molecules, and presentation of peptides to CD8 T cells. However, ICP47 binds poorly to murine TAP1/2 and so inhibits antigen presentation by MHC class I in mice much less efficiently than in humans, limiting the utility of murine models to address the importance of MHC class I inhibition in HSV immunopathogenesis. To address this limitation, we generated recombinant HSVs that efficiently inhibit antigen presentation by murine MHC class I. These recombinant viruses prevented cytotoxic T lymphocyte killing of infected cells in vitro, replicated to higher titers in the central nervous system, and induced paralysis more frequently than control HSV. This increase in virulence was due to inhibition of antigen presentation to CD8 T cells, since these differences were not evident in MHC class I-deficient mice or in mice in which CD8 T cells were depleted. Inhibition of MHC class I by the recombinant viruses did not impair the induction of the HSV-specific CD8 T-cell response, indicating that cross-presentation is the principal mechanism by which HSV-specific CD8 T cells are induced. This inhibition in turn facilitates greater viral entry, replication, and/or survival in the central nervous system, leading to an increased incidence of paralysis.

  15. Adsorption and inhibitive properties of sildenafil (Viagra for zinc in hydrochloric acid solution

    Directory of Open Access Journals (Sweden)

    A.S. Fouda

    Full Text Available Sildenafil (Viagra was investigated as corrosion inhibitor for Zn in 1 M HCl solution using chemical and electrochemical methods at 25 °C. Electrochemical results showed that this drug is efficient inhibitor for Zn in HCl and the inhibition efficiency (IE reached to 91% at 300 ppm. The IE increases with the drug concentration and decreases with increasing temperature. The adsorption of this drug on Zn surface follows Langmuir adsorption isotherm. The polarization plots revealed that Sildenafil acts as a mixed-type inhibitor. The thermodynamic parameters of activation and adsorption were calculated and discussed. The surface morphology of the Zn specimens was evaluated using scanning electron microscope (SEM, energy dispersive X-ray (EDX, atomic force microscopy (AFM and Fourier transform infrared spectroscopy (FTIR techniques. Keywords: Zn, Corrosion inhibition, HCl, SEM, EDX, AFM, FTIR, Sildenafil drug

  16. Corrosion Inhibition Activities of Chemical Compound for Mild Steel in Hydrochloric Acid

    Directory of Open Access Journals (Sweden)

    Ahmed Khaleel Al-Okbi

    2017-11-01

    Full Text Available Corrosive solution (Hydrochloric acid has been over and over utilized in manufacturing processes, covering cleaning pickling, acid descaling by acids and oil fully acidize. Inhibition effect of the inhibitor named "2-(((1H-benzo[d]imidazol-2-yl iminomethylphenol" [BIMP] on mild steel in 1 M hydrochloric acid has been scanned employing a technique named weight loss. The results of the study reveal that the inhibition efficiency of BIMP depends on its concentration and attains approximately 81.4% at 0.5 g/L. It is found that the BIMP shows significant action as an inhibitor for mild steel corrosion in corrosive media. BIMP has efficiency raised regarding to temperature decreasing and raising BIMP concentrations.  

  17. Impairment of GABA transporter GAT-1 terminates cortical recurrent network activity via enhanced phasic inhibition

    Directory of Open Access Journals (Sweden)

    Daniel Simon Razik

    2013-09-01

    Full Text Available In the central nervous system, GABA transporters (GATs very efficiently clear synaptically released GABA from the extracellular space, and thus exert a tight control on GABAergic inhibition. In neocortex, GABAergic inhibition is heavily recruited during recurrent phases of spontaneous action potential activity which alternate with neuronally quiet periods. Therefore, such activity should be quite sensitive to minute alterations of GAT function. Here, we explored the effects of a gradual impairment of GAT-1 and GAT-2/3 on spontaneous recurrent network activity – termed network bursts and silent periods – in organotypic slice cultures of rat neocortex. The GAT-1 specific antagonist NO-711 depressed activity already at nanomolar concentrations (IC50 for depression of spontaneous multiunit firing rate of 42 nM, reaching a level of 80% at 500-1000 nM. By contrast, the GAT-2/3 preferring antagonist SNAP-5114 had weaker and less consistent effects. Several lines of evidence pointed towards an enhancement of phasic GABAergic inhibition as the dominant activity-depressing mechanism: network bursts were drastically shortened, phasic GABAergic currents decayed slower, and neuronal excitability during ongoing activity was diminished. In silent periods, NO-711 had little effect on neuronal excitability or membrane resistance, quite in contrast to the effects of muscimol, a GABA mimetic which activates GABAA receptors tonically. Our results suggest that an enhancement of phasic GABAergic inhibition efficiently curtails cortical recurrent activity and may mediate antiepileptic effects of therapeutically relevant concentrations of GAT-1 antagonists.

  18. Inhibition of copper corrosion by the formation of Schiff base self-assembled monolayers

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jing [Department of Chemical and Biological Engineering, Guilin University of Technology, Guilin 541004 (China); Liu, Zheng, E-mail: lisa4.6@163.com [Department of Chemical and Biological Engineering, Guilin University of Technology, Guilin 541004 (China); Han, Guo-Cheng, E-mail: hangc1981@163.com [School of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin 541004 (China); Chen, Shi-Liang [Department of Chemical and Biological Engineering, Guilin University of Technology, Guilin 541004 (China); Chen, Zhencheng [School of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin 541004 (China)

    2016-12-15

    Highlights: • The highest inhibition efficiency was 93.9% for CO{sub 2}-saturated simulative oilfield water. • HD2-SAMs on copper surface exhibited excellent inhibition effect at 30 °C. • The adsorption behavior of HD2-SAM followed the Langmuir adsorption isotherm. • The adsorption behavior of HD2-SAM is a typically chemical adsorption. - Abstract: Self-assembled monolayers (SAMs) of 4-((2-thiophenecarboxylic acid hydrazide) methylene) benzoic acid (HD2) (denoted as HD2-SAMs) were formed on copper surface. The SAMs were characterized by scanning electron microscopy and X-ray photoelectron spectroscopy. Polarization curve and weight loss methods indicated that the highest inhibition efficiency was 93.9% for CO{sub 2}-saturated simulative oilfield water at a self-assembled time of 3 h. Potential-time curve, electrochemical impedance tests showed that HD2-SAMs on copper surface exhibited excellent inhibition effect at 30 °C. The adsorption behavior of HD2-SAMs on the copper surface followed the Langmuir adsorption isotherm, which was indicative of typically chemical adsorption. Quantum chemistry calculation showed that O and N atoms can interact with Cu atoms by coordination bonds which were the mainly active area of the adsorption of HD2 molecules.

  19. Electrochemical study of corrosion inhibition of stainless steel in phosphoric medium

    Energy Technology Data Exchange (ETDEWEB)

    Hnini, K.; Chtaini, A. [Laboratoire d' Electrochimie et de Bio Corrosion, Faculte des Sciences et Techniques, Beni-Mellal (Morocco); Khouili, M.; Elbouadili, A. [Laboratoire de Chimie Organique et Analytique, Faculte des Sciences et Techniques, Beni-Mellal (Morocco)

    2004-07-01

    The corrosion of metals represents a terrible waste of both natural resources and money, the failure of some stainless steel resulting from pitting corrosion is some times considered a technological problem, consequently, much effort has been expended in attempting to understand and overcome the corrosion therefore, many stainless steel/ environment combinations have been studied. The use of heterocyclic compounds as inhibitors is one of the most practical methods for protection against corrosion in acidic media. In continuation of our work on development of macrocyclic compounds as corrosion inhibitors we report in our study the corrosion inhibiting behaviour of organic compound Methoxy-2-Allyl-4 Phenol (MAP) containing coordinating and conjugation groups, at three forms (natural, polymerized and chemically treated) on the corrosion of stainless steel in phosphoric acid. This study focused on the comparison for corrosion inhibition proprieties of these different applications using potentiodynamic polarization, electrochemical impedance spectroscopy and SEM. The specimen was evaluated to determine change in his corrosion potential and resistance polarization; These MAP products have exhibited corrosion inhibition by maintaining a high resistance polarization (low corrosion rate) in each application. These results reveal that this compound is efficient inhibitor in all forms; the most inhibition efficiency is obtained with polymerized form. To further evaluate the test data, the steel surfaces were analyzed using scanning electron microscopy, SEM observations of surface treated concrete confirmed presence of inhibitor on the steel surfaces. (authors)

  20. Alpha-mangostin inhibits both dengue virus production and cytokine/chemokine expression.

    Science.gov (United States)

    Tarasuk, Mayuri; Songprakhon, Pucharee; Chimma, Pattamawan; Sratongno, Panudda; Na-Bangchang, Kesara; Yenchitsomanus, Pa-Thai

    2017-08-15

    Since severe dengue virus (DENV) infection in humans associates with both high viral load and massive cytokine production - referred to as "cytokine storm", an ideal drug for treatment of DENV infection should efficiently inhibit both virus production and cytokine expression. In searching for such an ideal drug, we discovered that α-mangostin (α-MG), a major bioactive compound purified from the pericarp of the mangosteen fruit (Garcinia mangostana Linn), which has been used in traditional medicine for several conditions including trauma, diarrhea, wound infection, pain, fever, and convulsion, inhibits both DENV production in cultured hepatocellular carcinoma HepG2 and Huh-7 cells, and cytokine/chemokine expression in HepG2 cells. α-MG could also efficiently inhibit all four serotypes of DENV. Treatment of DENV-infected cells with α-MG (20μM) significantly reduced the infection rates of four DENV serotypes by 47-55%. α-MG completely inhibited production of DENV-1 and DENV-3, and markedly reduced production of DENV-2 and DENV-4 by 100 folds. Furthermore, it could markedly reduce cytokine (IL-6 and TNF-α) and chemokine (RANTES, MIP-1β, and IP-10) transcription. These actions of α-MG are more potent than those of antiviral agent (ribavirin) and anti-inflammatory drug (dexamethasone). Thus, α-MG is potential to be further developed as therapeutic agent for DENV infection. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Simvastatin inhibits Candida albicans biofilm in vitro.

    Science.gov (United States)

    Liu, Geoffrey; Vellucci, Vincent F; Kyc, Stephanie; Hostetter, Margaret K

    2009-12-01

    By inhibiting the conversion of 3-hydroxy-3-methylglutaryl CoA (HMG-CoA) to mevalonate, statins impair cholesterol metabolism in humans. We reasoned that statins might similarly interfere with the biosynthesis of ergosterol, the major sterol of the yeast cell membrane. As assessed by spectrophotometric and microscopic analysis, significant inhibition of biofilm production was noted after 16-h incubation with 1, 2.5, and 5 muM simvastatin, concentrations that did not affect growth, adhesion, or hyphal formation by C. albicans in vitro. Higher concentrations (10, 20, and 25 muM simvastatin) inhibited biofilm by >90% but also impaired growth. Addition of exogenous ergosterol (90 muM) overcame the effects of 1 and 2.5 muM simvastatin, suggesting that at least one mechanism of inhibition is interference with ergosterol biosynthesis. Clinical isolates from blood, skin, and mucosal surfaces produced biofilms; biofilms from bloodstream isolates were similarly inhibited by simvastatin. In the absence of fungicidal activity, simvastatin's interruption of a critical step in an essential metabolic pathway, highly conserved from yeast to man, has unexpected effects on biofilm production by a eukaryotic pathogen.

  2. Aspartate inhibits Staphylococcus aureus biofilm formation.

    Science.gov (United States)

    Yang, Hang; Wang, Mengyue; Yu, Junping; Wei, Hongping

    2015-04-01

    Biofilm formation renders Staphylococcus aureus highly resistant to conventional antibiotics and host defenses. Four D-amino acids (D-Leu, D-Met, D-Trp and D-Tyr) have been reported to be able to inhibit biofilm formation and disassemble established S. aureus biofilms. We report here for the first time that both D- and L-isoforms of aspartate (Asp) inhibited S. aureus biofilm formation on tissue culture plates. Similar biofilm inhibition effects were also observed against other staphylococcal strains, including S. saprophyticus, S. equorum, S. chromogenes and S. haemolyticus. It was found that Asp at high concentrations (>10 mM) inhibited the growth of planktonic N315 cells, but at subinhibitory concentrations decreased the cellular metabolic activity without influencing cell growth. The decreased cellular metabolic activity might be the reason for the production of less protein and DNA in the matrix of the biofilms formed in the presence of Asp. However, varied inhibition efficacies of Asp were observed for biofilms formed by clinical staphylococcal isolates. There might be mechanisms other than decreasing the metabolic activity, e.g. the biofilm phenotypes, affecting biofilm formation in the presence of Asp. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  3. Levetiracetam inhibits neurotransmitter release associated with CICR.

    Science.gov (United States)

    Fukuyama, Kouji; Tanahashi, Shunsuke; Nakagawa, Masanori; Yamamura, Satoshi; Motomura, Eishi; Shiroyama, Takashi; Tanii, Hisashi; Okada, Motohiro

    2012-06-19

    To define the antiepileptic mechanisms of levetiracetam (LEV), the present study determined the concentration-dependent effects of locally perfused LEV on the releases of norepinephrine, dopamine, serotonin, l-glutamate and GABA induced by 50 mMK(+)-evoked stimulation and agonists of ryanodine receptor (RyR) and inositol-triphosphate receptor (IP3R) in the median prefrontal cortex (mPFC) using in vivo microdialysis. Local perfusion with LEV (10, 30 and 100 μM) alone did not affect the extracellular levels of all neurotransmitters in the mPFC. The release of neurotransmitters induced by K(+)-evoked stimulation was inhibited by perfusion with LEV in a concentration-dependent manner, and those induced by agonists of RyR and IP3R were also inhibited by LEV. Specifically, the RyR-induced release was inhibited by 10 μM LEV, whereas the IP3R-induced release was inhibited by 100 μM LEV, but not by 10 or 30 μM LEV. The above results suggest that LEV has little effect on the components of normal synaptic transmission but selectively inhibits transmission induced by neuronal hyperactivation. Thus, the mechanisms of the antiepileptic and neuroprotective actions of LEV seem to be mediated, at least in part, through the combination of these two inhibitory effects on depolarization-induced and CICR-associated neurotransmitter releases. Copyright © 2012. Published by Elsevier Ireland Ltd.

  4. Synergistic Effect of Azadirachta Indica Extract and Iodide Ions on the Corrosion Inhibition of Aluminium in Acid Media

    Energy Technology Data Exchange (ETDEWEB)

    Arab, S. T.; Al- Turkustani, A. M.; Al- Dhahiri, R. H. [King Abd El- Aziz University, Jeddah (Saudi Arabia)

    2008-06-15

    The synergistic action caused by iodide ions on the corrosion inhibition of aluminium (Al) in 0.5 M HCl in the presence of Azadirachta Indica (AZI) plant extract has been investigated using potintiodynamic polarization and impedance techniques. It is found that AZI extract inhibits the corrosion of aluminium in 0.5 M HCl. The inhibition efficiency increases with the increase in AZI extract concentration, until 24% v/v of AZI extract, then Inh.% is decreased with father increase in AZI extract concentration. The adsorption of this extract in the studied concentration is found to obey Frewendlish adsorption isotherm. The addition of iodide ions enhances the inhibition efficiency to a considerable extent. The increase in Inh.% values in presence of fixed concentration of iodide ions indicates that AZI extract forms an insoluble complex at lower AZI extract concentrations by undergoing a joint adsorption. But at higher concentrations of AZI extract, competitive adsorption is found between iodide ions and the formed complex leading to less Inh.%. The Inh.% decreased in presence of iodide ions with AZI extract than in presence of AZI extract alone at all studied iodide concentrations. The synergism parameter S {sub θ} is defined and calculated from surface coverage values. This parameter in the case of AZI extract is found to be more than unity, indicating that the enhanced inhibition efficiency caused by the addition of iodide ions.

  5. Inhibition of 2-hexenal autooxidation by essential oils from clove bud, laurel, cardamom, nutmeg and mace

    OpenAIRE

    Misharina, Tamara; Terenina, Margarita; Krikunova, Natalia

    2011-01-01

    The antioxidant properties and stability during the storage of hexane solutions of 5 individual essential oils from clove bud (Caryophyllus aromaticus L.), cardamom (Elettaria cardamomum L.), laurel (Laurus nobilis L.), nutmeg (Myristica fragrans Houtt.), and mace (Myristica fragrans Houtt) were studied by the method of capillary gas-liquid chromatography. We assessed the antioxidant properties by the efficiency of autooxidation inhibition of aliphatic aldehyde (trans-2-hexenal) into the corr...

  6. Corrosion Inhibition of Mild Steel in Hydrochloric Acid by Sodium Lauryl Sulfate (SLS

    Directory of Open Access Journals (Sweden)

    Atul Kumar

    2008-01-01

    Full Text Available Effect of Sodium Lauryl Sulfate (SLS, a surfactant on corrosion of mild steel in 1 M hydrochloric acid was studied using three techniques namely: weight loss, electrochemical polarization and metallurgical research microscopy. Results obtained reveal that SLS is good inhibitor and shows very good corrosion inhibition efficiency (IE. The IE was found to vary with concentration of inhibitor and temperature. The electrochemical polarization result revealed that SLS is anodic in nature.

  7. Material Efficiency of Building Construction

    Directory of Open Access Journals (Sweden)

    Antti Ruuska

    2014-07-01

    Full Text Available Better construction and use of buildings in the European Union would influence 42% of final energy consumption, about 35% of our greenhouse gas emissions and more than 50% of all extracted materials. It could also help to save up to 30% of water consumption. This paper outlines and draws conclusions about different aspects of the material efficiency of buildings and assesses the significance of different building materials on the material efficiency. The research uses an extensive literature study and a case-study in order to assess: should the depletion of materials be ignored in the environmental or sustainability assessment of buildings, are the related effects on land use, energy use and/or harmful emissions significant, should related indicators (such as GHGs be used to indicate the material efficiency of buildings, and what is the significance of scarce materials, compared to the use of other building materials. This research suggests that the material efficiency should focus on the significant global impacts of material efficiency; not on the individual factors of it. At present global warming and greenhouse gas emissions are among the biggest global problems on which material efficiency has a direct impact on. Therefore, this paper suggests that greenhouse gas emissions could be used as an indicator for material efficiency in building.

  8. Membrane processes for alcohol-water separation: Improving the energy efficiency of biofuel production

    Science.gov (United States)

    The economics and environmental impact of producing fuels and chemicals biologically can be a strong function of the efficiency with which the fermentation products are removed from the biological media. Due to growth inhibition by some fermentation products, including ethanol an...

  9. Inhibition of ethylene production by putrescine alleviates aluminium-induced root inhibition in wheat plants

    Science.gov (United States)

    Yu, Yan; Jin, Chongwei; Sun, Chengliang; Wang, Jinghong; Ye, Yiquan; Zhou, Weiwei; Lu, Lingli; Lin, Xianyong

    2016-01-01

    Inhibition of root elongation is one of the most distinct symptoms of aluminium (Al) toxicity. Although putrescine (Put) has been identified as an important signaling molecule involved in Al tolerance, it is yet unknown how Put mitigates Al-induced root inhibition. Here, the possible mechanism was investigated by using two wheat genotypes differing in Al resistance: Al-tolerant Xi Aimai-1 and Al-sensitive Yangmai-5. Aluminium caused more root inhibition in Yangmai-5 and increased ethylene production at the root apices compared to Xi Aimai-1, whereas the effects were significantly reversed by ethylene biosynthesis inhibitors. The simultaneous exposure of wheat seedlings to Al and ethylene donor, ethephon, or ethylene biosynthesis precursor, 1-aminocyclopropane-1-carboxylic acid (ACC), increased ethylene production and aggravated root inhibition, which was more pronounced in Xi Aimai-1. In contrast, Put treatment decreased ethylene production and alleviated Al-induced root inhibition in both genotypes, and the effects were more conspicuous in Yangmai-5. Furthermore, our results indicated that Al-induced ethylene production was mediated by ACC synthase (ACS) and ACC oxidase, and that Put decreased ethylene production by inhibiting ACS. Altogether, these findings indicate that ethylene is involved in Al-induced root inhibition and this process could be alleviated by Put through inhibiting ACS activity. PMID:26744061

  10. Inhibition of ethylene production by putrescine alleviates aluminium-induced root inhibition in wheat plants.

    Science.gov (United States)

    Yu, Yan; Jin, Chongwei; Sun, Chengliang; Wang, Jinghong; Ye, Yiquan; Zhou, Weiwei; Lu, Lingli; Lin, Xianyong

    2016-01-08

    Inhibition of root elongation is one of the most distinct symptoms of aluminium (Al) toxicity. Although putrescine (Put) has been identified as an important signaling molecule involved in Al tolerance, it is yet unknown how Put mitigates Al-induced root inhibition. Here, the possible mechanism was investigated by using two wheat genotypes differing in Al resistance: Al-tolerant Xi Aimai-1 and Al-sensitive Yangmai-5. Aluminium caused more root inhibition in Yangmai-5 and increased ethylene production at the root apices compared to Xi Aimai-1, whereas the effects were significantly reversed by ethylene biosynthesis inhibitors. The simultaneous exposure of wheat seedlings to Al and ethylene donor, ethephon, or ethylene biosynthesis precursor, 1-aminocyclopropane-1-carboxylic acid (ACC), increased ethylene production and aggravated root inhibition, which was more pronounced in Xi Aimai-1. In contrast, Put treatment decreased ethylene production and alleviated Al-induced root inhibition in both genotypes, and the effects were more conspicuous in Yangmai-5. Furthermore, our results indicated that Al-induced ethylene production was mediated by ACC synthase (ACS) and ACC oxidase, and that Put decreased ethylene production by inhibiting ACS. Altogether, these findings indicate that ethylene is involved in Al-induced root inhibition and this process could be alleviated by Put through inhibiting ACS activity.

  11. Polish Foundation for Energy Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    The Polish Foundation for Energy Efficiency (FEWE) was established in Poland at the end of 1990. FEWE, as an independent and non-profit organization, has the following objectives: to strive towards an energy efficient national economy, and to show the way and methods by use of which energy efficiency can be increased. The activity of the Foundation covers the entire territory of Poland through three regional centers: in Warsaw, Katowice and Cracow. FEWE employs well-known and experienced specialists within thermal and power engineering, civil engineering, economy and applied sciences. The organizer of the Foundation has been Battelle Memorial Institute - Pacific Northwest Laboratories from the USA.

  12. The Efficiency of Educational Production

    DEFF Research Database (Denmark)

    Bogetoft, Peter; Heinesen, Eskil; Tranæs, Torben

    and maintain the same graduation/completion rates as today if the country could achieve the same level of cost effectiveness as its most efficient counterparts. Comparing Denmark to a group of the richest OECD countries reveals that potential savings lie between 12 and 34 percent. Figures that fall to between...... to explain the higher costs of upper secondary education. On the output side, if earnings and levels of employment among those who complete their education are taken into account, then Denmark is in fact found to be efficient. However, this high level of efficiency has become less clear-cut in recent years...

  13. Mapuche herbal medicine inhibits blood platelet aggregation.

    Science.gov (United States)

    Falkenberg, Susan Skanderup; Tarnow, Inge; Guzman, Alfonso; Mølgaard, Per; Simonsen, Henrik Toft

    2012-01-01

    12 plant species traditionally used by the Mapuche people in Chile to treat wounds and inflammations have been evaluated for their direct blood platelet inhibition. Seven of the 12 tested plant species showed platelet inhibitory effect in sheep blood, and four of these were also able to inhibit the ADP- (5.0 μM) and collagen- (2.0 μg/mL) induced aggregations in human blood. These four species in respective extracts (in brackets) were Blechnum chilense (MeOH), Luma apiculata (H(2)O), Amomyrtus luma (DCM : MeOH 1 : 1) and Cestrum parqui (DCM : MeOH 1 : 1). The platelet aggregating inhibitory effects of A. luma (DCM : MeOH 1 : 1), and L. apiculata (H(2)O) were substantial and confirmed by inhibition of platelet surface activation markers.

  14. The ammonium sulfate inhibition of human angiogenin.

    Science.gov (United States)

    Chatzileontiadou, Demetra S M; Tsirkone, Vicky G; Dossi, Kyriaki; Kassouni, Aikaterini G; Liggri, Panagiota G V; Kantsadi, Anastassia L; Stravodimos, George A; Balatsos, Nikolaos A A; Skamnaki, Vassiliki T; Leonidas, Demetres D

    2016-09-01

    In this study, we investigate the inhibition of human angiogenin by ammonium sulfate. The inhibitory potency of ammonium sulfate for human angiogenin (IC50 = 123.5 ± 14.9 mm) is comparable to that previously reported for RNase A (119.0 ± 6.5 mm) and RNase 2 (95.7 ± 9.3 mm). However, analysis of two X-ray crystal structures of human angiogenin in complex with sulfate anions (in acidic and basic pH environments, respectively) indicates an entirely distinct mechanism of inhibition. While ammonium sulfate inhibits the ribonucleolytic activity of RNase A and RNase 2 by binding to the active site of these enzymes, sulfate anions bind only to peripheral substrate anion-binding subsites of human angiogenin, and not to the active site. © 2016 Federation of European Biochemical Societies.

  15. [Inhibition of Denitrification by Total Phenol Load of Coal Gasification Wastewater].

    Science.gov (United States)

    Zhang, Yu-ying; Chen, Xiu-rong; Wang, Lu; Li, Jia-hui; Xu, Yan; Zhuang, You-jun; Yu, Ze-ya

    2016-03-15

    High loaded phenolic pollutants, refractory and high toxic, which existed in coal gasification wastewater, could cause the inhibition of sludge activity. In biological denitrification process of activated sludge treatment system, people tend to focus on the phenol inhibition on the efficiency and activity of nitrifying bacteria while there are few researches on the denitrification process. In order to investigate the inhibition of phenolic compounds from coal gasification wastewater on the denitrification and sludge activity, we used anoxic denitrification system to indentify the influence of different phenol load on denitrification efficiency (removal efficiency of NO₃⁻-N and NO₂⁻-N) as well as the stress and degradation activity of sludge. The results showed that when the concentration of total phenol was changed from 50 mg · L⁻¹ to 200 mg · L⁻¹, the removal rates of NO₃⁻-N and NO₂⁻-N were changed from 55% and 25% to 83% and 83% respectively. In the process of sludge domestication, the characteristics of denitrifying sludge were influenced to a certain degree.

  16. Quantum efficiency of GaN photocathode under different illumination

    Science.gov (United States)

    Wang, Xiaohui; Chang, Benkang; Du, Yujie; Qiao, Jianliang

    2011-07-01

    GaN samples are activated by Cs/O under illumination of deuterium lamp, 300 nm monochromatic light with power of 70 μW and 300 nm monochromatic light with power of 35 μW, respectively. Photocurrent is detected before activation under illumination of deuterium lamp. Quantum efficiency (QE) is tested after activation. The results indicate that GaN activated under 300 nm monochromatic light have higher QE than that under deuterium lamp, and no obvious difference is detected between different power 300 nm monochromatic light. The photocurrent before activation inhibits the adsorption of Cs on the GaN surface, which decrease the QE of GaN.

  17. The inhibition of monoamine oxidase by esomeprazole.

    Science.gov (United States)

    Petzer, A; Pienaar, A; Petzer, J P

    2013-09-01

    Virtual screening of a library of drugs has suggested that esomeprazole, the S-enantiomer of omeprazole, may possess binding affinities for the active sites of the monoamine oxidase (MAO) A and B enzymes. Based on this finding, the current study examines the MAO inhibitory properties of esomeprazole. Using recombinant human MAO-A and MAO-B, IC50 values for the inhibition of these enzymes by esomeprazole were experimentally determined. To examine the reversibility of MAO inhibition by esomeprazole, the recoveries of the enzymatic activities after dilution of the enzyme-inhibitor complexes were evaluated. In addition, reversibility of inhibition was also examined by measuring the recoveries of enzyme activities after dialysis of enzyme-inhibitor mixtures. Lineweaver-Burk plots were constructed to evaluate the mode of MAO inhibition and to measure Ki values. The results document that esomeprazole inhibits both MAO-A and MAO-B with IC50 values of 23 µM and 48 µM, respectively. The interactions of esomeprazole with MAO-A and MAO-B are reversible and most likely competitive with Ki values for the inhibition of the respective enzymes of 8.99 µM and 31.7 µM. Considering the available pharmacokinetic data and typical therapeutic doses of esomeprazole, these inhibitory potencies are unlikely to be of pharmacological relevance in humans. The MAO inhibitory effects of esomeprazole should however be taken into consideration when using this drug in animal experiments where higher doses are often administered. © Georg Thieme Verlag KG Stuttgart · New York.

  18. Adsorption and corrosion inhibiting effect of riboflavin on Q235 mild steel corrosion in acidic environments

    Energy Technology Data Exchange (ETDEWEB)

    Chidiebere, Maduabuchi A. [Institute of Metal Research, Chinese Academy of Sciences, 62 Wencui Rd, Shenyang 110016 (China); Electrochemistry and Materials Science Research Laboratory, Department of Chemistry, Federal University of Technology Owerri, PMB 1526 Owerri (Nigeria); Oguzie, Emeka E. [Electrochemistry and Materials Science Research Laboratory, Department of Chemistry, Federal University of Technology Owerri, PMB 1526 Owerri (Nigeria); Liu, Li [Institute of Metal Research, Chinese Academy of Sciences, 62 Wencui Rd, Shenyang 110016 (China); Li, Ying, E-mail: liying@imr.ac.cn [Institute of Metal Research, Chinese Academy of Sciences, 62 Wencui Rd, Shenyang 110016 (China); Wang, Fuhui [Institute of Metal Research, Chinese Academy of Sciences, 62 Wencui Rd, Shenyang 110016 (China)

    2015-04-15

    The inhibiting effect of Riboflavin (RF) on Q235 mild steel corrosion in 1 M HCl and 0.5 M H{sub 2}SO{sub 4} at 30 °C temperature was investigated using electrochemical techniques (electrochemical impedance spectroscopy and potentiodynamic polarization). The obtained results revealed that RF inhibited the corrosion reaction in both acidic solutions. Maximum inhibition efficiency values in 1 M HCl and 0.5 M H{sub 2}SO{sub 4} were 83.9% and 71.4%, respectively, obtained for 0.0012 M RF. Polarization data showed RF to be a mixed-type inhibitor, while EIS results revealed that the RF species adsorbed on the metal surface. The adsorption of RF followed Langmuir adsorption isotherm. Atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) studies confirmed the formation of a protective layer adsorbed on the steel surface. Quantum chemical calculations were used to correlate the inhibition ability of RF with its electronic structural parameters. - Highlights: • The inhibitory mechanism was influenced by the nature of acid anions. • RF has reasonable inhibition effect especially in 1 M HCl solution. • Polarization studies showed that RF functioned as a mixed type inhibitor. • Improved surface morphology was observed in the presence of RF.

  19. ERK inhibition sensitizes CZ415-induced anti-osteosarcoma activity in vitro and in vivo.

    Science.gov (United States)

    Yin, Gang; Fan, Jin; Zhou, Wei; Ding, Qingfeng; Zhang, Jun; Wu, Xuan; Tang, Pengyu; Zhou, Hao; Wan, Bowen; Yin, Guoyong

    2017-10-10

    mTOR is a valuable oncotarget for osteosarcoma. The anti-osteosarcoma activity by a novel mTOR kinase inhibitor, CZ415, was evaluated. We demonstrated that CZ415 potently inhibited survival and proliferation of known osteosarcoma cell lines (U2OS, MG-63 and SaOs2), and primary human osteosarcoma cells. Further, CZ415 provoked apoptosis and disrupted cell cycle progression in osteosarcoma cells. CZ415 treatment in osteosarcoma cells concurrently blocked mTORC1 and mTORC2 activation. Intriguingly, ERK-MAPK activation could be a major resistance factor of CZ415. ERK inhibition (by MEK162/U0126) or knockdown (by targeted ERK1/2 shRNAs) dramatically sensitized CZ415-induced osteosarcoma cell apoptosis. In vivo , CZ415 oral administration efficiently inhibited U2OS tumor growth in mice. Its activity was further potentiated with co-administration of MEK162. Collectively, we demonstrate that ERK inhibition sensitizes CZ415-induced anti-osteosarcoma activity in vitro and in vivo . CZ415 could be further tested as a promising anti-osteosarcoma agent, alone or in combination of ERK inhibition.

  20. Different effect of proteasome inhibition on vesicular stomatitis virus and poliovirus replication.

    Directory of Open Access Journals (Sweden)

    Nickolay Neznanov

    2008-04-01

    Full Text Available Proteasome activity is an important part of viral replication. In this study, we examined the effect of proteasome inhibitors on the replication of vesicular stomatitis virus (VSV and poliovirus. We found that the proteasome inhibitors significantly suppressed VSV protein synthesis, virus accumulation, and protected infected cells from toxic effect of VSV replication. In contrast, poliovirus replication was delayed, but not diminished in the presence of the proteasome inhibitors MG132 and Bortezomib. We also found that inhibition of proteasomes stimulated stress-related processes, such as accumulation of chaperone hsp70, phosphorylation of eIF2alpha, and overall inhibition of translation. VSV replication was sensitive to this stress with significant decline in replication process. Poliovirus growth was less sensitive with only delay in replication. Inhibition of proteasome activity suppressed cellular and VSV protein synthesis, but did not reduce poliovirus protein synthesis. Protein kinase GCN2 supported the ability of proteasome inhibitors to attenuate general translation and to suppress VSV replication. We propose that different mechanisms of translational initiation by VSV and poliovirus determine their sensitivity to stress induced by the inhibition of proteasomes. To our knowledge, this is the first study that connects the effect of stress induced by proteasome inhibition with the efficiency of viral infection.

  1. Feedforward inhibition and synaptic scaling--two sides of the same coin?

    Directory of Open Access Journals (Sweden)

    Christian Keck

    Full Text Available Feedforward inhibition and synaptic scaling are important adaptive processes that control the total input a neuron can receive from its afferents. While often studied in isolation, the two have been reported to co-occur in various brain regions. The functional implications of their interactions remain unclear, however. Based on a probabilistic modeling approach, we show here that fast feedforward inhibition and synaptic scaling interact synergistically during unsupervised learning. In technical terms, we model the input to a neural circuit using a normalized mixture model with Poisson noise. We demonstrate analytically and numerically that, in the presence of lateral inhibition introducing competition between different neurons, Hebbian plasticity and synaptic scaling approximate the optimal maximum likelihood solutions for this model. Our results suggest that, beyond its conventional use as a mechanism to remove undesired pattern variations, input normalization can make typical neural interaction and learning rules optimal on the stimulus subspace defined through feedforward inhibition. Furthermore, learning within this subspace is more efficient in practice, as it helps avoid locally optimal solutions. Our results suggest a close connection between feedforward inhibition and synaptic scaling which may have important functional implications for general cortical processing.

  2. Inhibition of APOBEC3G Activity Impedes Double-Strand DNA Repair

    Science.gov (United States)

    Prabhu, Ponnandy; Shandilya, Shivender; Britan-Rosich, Elena; Nagler, Adi; Schiffer, Celia A.; Kotler, Moshe

    2015-01-01

    The cellular cytidine deaminase APOBEC3G (A3G) was first described as an anti-HIV-1 restriction factor by directly deaminating reverse transcripts of the viral genome. HIV-1 Vif neutralizes the activity of A3G, primarily by mediating degradation of A3G to establish effective infection in host target cells. Lymphoma cells, which express high amounts of A3G, can restrict Vif-deficient HIV-1. Interestingly, these cells are more stable in the face of treatments that result in dsDNA damage, such as ionizing irradiation (IR) and chemotherapies. Previously, we showed that the Vif-derived peptide (Vif25-39) efficiently inhibits A3G deamination, and increases sensitivity of lymphoma cells to IR. In the current study, we show that additional peptides derived from Vif, A3G and A3F, which contain the LYYF motif, inhibit deamination activity. Each residue in the Vif25-39 sequence moderately contributes to the inhibitory effect, while, replacing a single amino acid in the LYYF motif completely abrogate inhibition of deamination. Treatment of A3G-expressing lymphoma cells exposed to ionizing radiation with the new inhibitory peptides reduces double-strand break (DSB) repair after radiation. Incubation of cultured irradiated lymphoma cells with peptides that inhibit DSB repair halts their propagation. These results suggest that A3G may be a potential therapeutic target amenable to peptide and peptidomimetic inhibition. PMID:26460502

  3. Inhibition of APOBEC3G activity impedes double-stranded DNA repair.

    Science.gov (United States)

    Prabhu, Ponnandy; Shandilya, Shivender M D; Britan-Rosich, Elena; Nagler, Adi; Schiffer, Celia A; Kotler, Moshe

    2016-01-01

    The cellular cytidine deaminase APOBEC3G (A3G) was first described as an anti-HIV-1 restriction factor, acting by directly deaminating reverse transcripts of the viral genome. HIV-1 Vif neutralizes the activity of A3G, primarily by mediating degradation of A3G to establish effective infection in host target cells. Lymphoma cells, which express high amounts of A3G, can restrict Vif-deficient HIV-1. Interestingly, these cells are more stable in the face of treatments that result in double-stranded DNA damage, such as ionizing radiation and chemotherapies. Previously, we showed that the Vif-derived peptide (Vif25-39) efficiently inhibits A3G deamination, and increases the sensitivity of lymphoma cells to ionizing radiation. In the current study, we show that additional peptides derived from Vif, A3G, and APOBEC3F, which contain the LYYF motif, inhibit deamination activity. Each residue in the Vif25-39 sequence moderately contributes to the inhibitory effect, whereas replacing a single residue in the LYYF motif completely abrogates inhibition of deamination. Treatment of A3G-expressing lymphoma cells exposed to ionizing radiation with the new inhibitory peptides reduces double-strand break repair after irradiation. Incubation of cultured irradiated lymphoma cells with peptides that inhibit double-strand break repair halts their propagation. These results suggest that A3G may be a potential therapeutic target that is amenable to peptide and peptidomimetic inhibition. © 2015 FEBS.

  4. Insights into corrosion inhibition behavior of multi-active compounds for X65 pipeline steel in acidic oilfield formation water

    International Nuclear Information System (INIS)

    Tian, Huiwen; Li, Weihua; Hou, Baorong; Wang, Dapeng

    2017-01-01

    Highlights: • Novel inhibitors show high inhibition efficiency in oilfield formation water. • The inhibitor film exhibits a compact and uniform structure. • SVET and REQCM indicate inhibitors are more effective for the corroded steel. • XPS shows the active canters of inhibitor adsorption focus on the heteroatoms. - Abstract: Inhibition behavior of new designed inhibitors for X65 steel in CO 2 saturated oilfield formation water containing acetic acid has been investigated by electrochemical measurements, surface characterization, scanning vibrating electrode technique, rotating electrochemical quartz crystal microbalance, and X-ray photoelectron spectroscopy. It is found the inhibition efficiency can exceed 95% for each inhibitor at a concentration of 3 × 10 −4 mol/L. The inhibitor film exhibits a compact and uniform structure, which is more effective for the corroded rather than freshly prepared steel surface due to the facilitation of chemisorption. The active centers of inhibitor adsorption mainly focus on N, S atoms, and conjugation system.

  5. Correlation between electronic parameters and corrosion inhibition of benzothiazole derivatives- NMR parameters as important and neglected descriptors

    Science.gov (United States)

    Behzadi, Hadi; Forghani, Ali

    2017-03-01

    The relation between electronic properties and corrosion inhibitive performance of three benzothiazole derivatives 1,3-benzothiazol-2-amine (BTA), 6-methyl-1,3-benzothiazol-2-amine (MBTA) and 2-amino-1,3-benzthiazole-6-thiol (TBTA) has been investigated by density functional theory. The electronic properties including EHOMO, ELUMO and related parameters were calculated at the B3LYP/6-311++G(d,p) level. The chemical shielding CS tensors were introduced as important and neglected descriptors to evaluate inhibitive efficiency of corrosion inhibitors. Nuclear independent chemical shift (NICS) components, as an aromaticity criterion, were also investigated as local descriptor. Polarizability and CS descriptors, as second rank tensors, show the best correlations with inhibition efficiencies of studied inhibitors.

  6. Kinetic analysis of inhibition of glucoamylase and active site mutants via chemoselective oxime immobilization of acarbose on SPR chip surfaces

    DEFF Research Database (Denmark)

    Sauer, Jørgen; Abou Hachem, Maher; Svensson, Birte

    2013-01-01

    We here report a quantitative study on the binding kinetics of inhibition of the enzyme glucoamylase and how individual active site amino acid mutations influence kinetics. To address this challenge, we have developed a fast and efficient method for anchoring native acarbose to gold chip surfaces...

  7. The pattern recognition molecule deleted in malignant brain tumors 1 (DMBT1) and synthetic mimics inhibit liposomal nucleic acid delivery

    DEFF Research Database (Denmark)

    Lund Hansen, Pernille; Blaich, Stephanie; End, Caroline

    2011-01-01

    Liposomal nucleic acid delivery is a preferred option for therapeutic settings. The cellular pattern recognition molecule DMBT1, secreted at high levels in various diseases, and synthetic mimics efficiently inhibit liposomal nucleic acid delivery to human cells. These findings may have relevance ...

  8. Humic Acid-Like and Fulvic Acid-Like Inhibition on the Hydrolysis of Cellulose and Tributyrin

    NARCIS (Netherlands)

    Fernandes, Tania V.; van Lier, Jules B.; Zeeman, Grietje

    2015-01-01

    Enzymatic hydrolysis of complex wastes is a critical step for efficient biogas production in anaerobic digesters. Inhibition of this hydrolytic step was studied by addition of humic acid-like (HAL) and fulvic acid-like (FAL) substances, extracted from maize silage and fresh cow manure, to batch

  9. Humic Acid-Like and Fulvic Acid-Like Inhibition on the Hydrolysis of Cellulose and Tributyrin

    NARCIS (Netherlands)

    Fernandes, T.V.; Lier, van J.B.; Zeeman, Grietje

    2015-01-01

    Enzymatic hydrolysis of complex wastes is a critical step for efficient biogas production in anaerobic digesters. Inhibition of this hydrolytic step was studied by addition of humic acid-like (HAL) and fulvic acid-like (FAL) substances, extracted from maize silage and fresh cow manure, to batch

  10. Event-rate manipulation and its effect on arousal modulation and response inhibition in adults with high functioning autism

    NARCIS (Netherlands)

    Raymaekers, R; van der Meere, J; Roeyers, H

    The aim of the current study was to evaluate arousal modulation and response inhibition in adults with high functioning autism (HFA). Using a go/no-go paradigm with varying presentation rate, it was found that performance efficiency (Mean RT, Standard Deviation of RT and Errors of Commission) in

  11. Hyperoxia Inhibits T Cell Activation in Mice

    Science.gov (United States)

    Hughes-Fulford, M.; Meissler, J.; Aguayo, E. T.; Globus, R.; Aguado, J.; Candelario, T.

    2013-02-01

    Background: The immune response is blunted in mice and humans in spaceflight. The effects of hyperoxia in mice alter expression of some of the same immune response genes. If these two conditions are additive, there could be an increased risk of infection in long duration missions. Immunosuppression is seen in healthy astronauts who have flown in space; however little is known about the mechanisms that cause the reduced immunity in spaceflight. Here we examine the role of oxidative stress on mice exposed to periods of high O2 levels mimicking pre-breathing protocols and extravehicular activity (EVA). To prevent decompression sickness, astronauts are exposed to elevated oxygen (hyperoxia) before and during EVA activities. Spaceflight missions may entail up to 24 hours of EVA per crewmember per week to perform construction and maintenance tasks. The effectiveness and success of these missions depends on designing EVA systems and protocols that maximize human performance and efficiency while minimizing health and safety risks for crewmembers. To our knowledge, no studies have been conducted on the immune system under 100% oxygen exposures to determine the potential for immune compromise due to prolonged and repeated EVAs. Methods: Animals were exposed to hyperoxic or control conditions for 8 hours per day over a period of 3 days, initiated 4 hours into the dark cycle (12h dark/12h light), using animal environmental control cabinets and oxygen controller (Biospherix, Lacona, NY). Experimental mice were exposed to 98-100% oxygen as a model for pre-breathing and EVA conditions, while control mice were maintained in chambers supplied with compressed air. These are ground control studies where we use real-time RTPCR (qRTPCR) to measure gene expression of the early immune gene expression during bead activation of splenocytes of normoxic and hyperoxic mice. All procedures were reviewed and approved by the IACUC at Ames Research Center. After the last 8h of hyperoxic exposure

  12. Sprout inhibition in roots, tubers and bulbs

    International Nuclear Information System (INIS)

    Luna C, P.C.

    1992-05-01

    The treatment with ionizing radiations to low dose impedes that appear sprouts in the tubers (potatoes); bulbs (onion and garlic) and in roots like the ginger and the yucca. The purpose is to inhibit the germination during the process of manipulation and storage, and this way to avoid the lost ones post crop of these products. The radiation dose required to inhibit the germination goes to depend of: the development conditions, the differences of variety, of the storage state of the bulbs and the conditions of cured and storage. (Author)

  13. Enzyme inhibition activities of Andrachne cardifolia Muell.

    Science.gov (United States)

    Ahmad, Bashir; Shah, S M Hassan; Bashir, Shumaila; Shah, Jehandar

    2007-04-01

    The crude methanolic extract and various fractions of Andrachne cardifolia Muell, including chloroform, ethyl acetate and n-butanol fractions were subjected to in vitro enzyme inhibition activity against acetylcholinesterase, butyrylcholinesterase, lipoxygenase and urease enzymes. A significant enzyme inhibition activity (40-89%) was shown by the crude methanolic extract and its fractions against lipoxygenase, while low to significant activity (40-71%) against butyrylcholinesterase. The crude methanolic extract and its various fractions demonstrated poor to significant activity (25-73%) against acetylcholinesterase and no activity against urease.

  14. Many Putative Endocrine Disruptors Inhibit Prostaglandin Synthesis

    DEFF Research Database (Denmark)

    Kristensen, David M.; Skalkam, Maria L.; Audouze, Karine Marie Laure

    2011-01-01

    Background: Prostaglandins (PGs) play key roles in development and maintenance of homeostasis of the adult body. Despite these important roles, it remains unclear whether the PG pathway is a target for endocrine disruption. However, several known endocrine disrupting compounds (EDCs) share a high...... of endocrine disruption. Results: We found that many known EDCs inhibit the PG pathway in a mouse Sertoli cell line and in human primary mast cells. The EDCs also reduced PG synthesis in ex vivo rat testis and it was correlated with a reduced testosterone production. The inhibition of PG synthesis occurs...

  15. Inhibition of soybean urease by triketone oximes.

    Science.gov (United States)

    Tarun, E I; Rubinov, D B; Metelitza, D I

    2004-12-01

    Competitive inhibition of soybean urease by 15 triketone oximes has been studied at 36 degrees C in aqueous solution (pH 4.95). The studied oximes are supposed chelators for the nickel atom in the urease metallocenter. The inhibition constants of urea hydrolysis (K(i)) varied in the range 2.7-248 microM depending on the oxime structure. Analysis of this dependency demonstrates that the optimal inhibitor is the one containing carbonyl group in position 1 of the cycle, the ethoxyimino group and alkyl residue in the substituent in position 2, as well as the methoxycarbonyl group in position 4 of the cycle.

  16. Peptide inhibition of human cytomegalovirus infection

    Directory of Open Access Journals (Sweden)

    Morris Cindy A

    2011-02-01

    Full Text Available Abstract Background Human cytomegalovirus (HCMV is the most prevalent congenital viral infection in the United States and Europe causing significant morbidity and mortality to both mother and child. HCMV is also an opportunistic pathogen in immunocompromised individuals, including human immunodeficiency virus (HIV- infected patients with AIDS, and solid organ and allogeneic stem cell transplantation recipients. Current treatments for HCMV-associated diseases are insufficient due to the emergence of drug-induced resistance and cytotoxicity, necessitating novel approaches to limit HCMV infection. The aim of this study was to develop therapeutic peptides targeting glycoprotein B (gB, a major glycoprotein of HCMV that is highly conserved across the Herpesviridae family, that specifically inhibit fusion of the viral envelope with the host cell membrane preventing HCMV entry and infection. Results Using the Wimley-White Interfacial Hydrophobicity Scale (WWIHS, several regions within gB were identified that display a high potential to interact with lipid bilayers of cell membranes and hydrophobic surfaces within proteins. The ability of synthetic peptides analogous to WWIHS-positive sequences of HCMV gB to inhibit viral infectivity was evaluated. Human foreskin fibroblasts (HFF were infected with the Towne-GFP strain of HCMV (0.5 MOI, preincubated with peptides at a range of concentrations (78 nm to 100 μM, and GFP-positive cells were visualized 48 hours post-infection by fluorescence microscopy and analyzed quantitatively by flow cytometry. Peptides that inhibited HCMV infection demonstrated different inhibitory concentration curves indicating that each peptide possesses distinct biophysical properties. Peptide 174-200 showed 80% inhibition of viral infection at a concentration of 100 μM, and 51% and 62% inhibition at concentrations of 5 μM and 2.5 μM, respectively. Peptide 233-263 inhibited infection by 97% and 92% at concentrations of 100

  17. Inhibition and Adjective Learning in Bilingual and Monolingual Children

    Science.gov (United States)

    Yoshida, Hanako; Tran, Duc N.; Benitez, Viridiana; Kuwabara, Megumi

    2011-01-01

    The ability to control attention – by inhibiting pre-potent, yet no longer relevant information – is an essential skill in all of human learning, and increasing evidence suggests that this ability is enhanced in language learning environments in which the learner is managing and using more than one language. One question waiting to be addressed is whether such efficient attentional control plays a role in word learning. That is, children who must manage two languages also must manage to learn two languages and the advantages of more efficient attentional control may benefit aspects of language learning within each language. This study compared bilingual and monolingual children’s performances in an artificial word-learning task and in a non-linguistic task that measures attention control. Three-year-old monolingual and bilingual children with similar vocabulary development participated in these tasks. The results replicate earlier work showing advanced attentional control among bilingual children and suggest that this better attentional control may also benefit better performance in novel adjective learning. The findings provide the first direct evidence of a relation between performances in an artificial word-learning task and in an attentional control task. We discuss this finding with respect to the general relevance of attentional control for lexical learning in all children and with respect to current views of bilingual children’s word learning. PMID:21949512

  18. Is energy efficiency environmentally friendly?

    Energy Technology Data Exchange (ETDEWEB)

    Herring, H. [Open University, Milton Keynes (United Kingdom). Energy and Environment Research Unit

    2000-07-01

    The paper challenges the view that improving the efficiency of energy use will lead to a reduction in national energy consumption, and hence is an effective policy for reducing CO{sub 2} emissions. It argues that improving energy efficiency lowers the implicit price of energy and hence makes its use more affordable, thus leading to greater use. The paper presents the views of economists, as well as green critics of 'efficiency' and the 'dematerialization' thesis. It argues that a more effective CO{sub 2} policy is to concentrate on shifting to non-fossil fuel, like renewables, subsidized through a carbon tax. Ultimately what is needed, to limit energy consumption is energy conservation not energy efficiency. 44 refs.

  19. EFFICIENCY OF POMEGRANATE SEED OIL

    Directory of Open Access Journals (Sweden)

    Sukru Karatas

    2014-01-01

    Full Text Available In this paper pomegranate kinds that reach to harvest maturity which are produced in commercial scales in Adana, Antalya, Finike and Kilis regions in Turkey and also Hicaz and Eksilik kinds are chosen randomly to be investigated. Seed efficiencies, grain ratios, oil efficiency of these chosen pomegranate kinds were studied. According to this study, pomegranate kind taken from Kilis region is found to have the highest grain efficieny with a ratio of 71% and pomegranate kind taken from Hicaz region is found to have the highest seed oil with a ratio of 18%. Also various solvent efficiencies including Hexan, Diethylether and petroleum ether on pomegranate seed oil is examined and most efficient one is obtained with Diethylether.

  20. The Efficiency of Educational Production

    DEFF Research Database (Denmark)

    Bogetoft, Peter; Heinesen, Eskil; Tranæs, Torben

    2015-01-01

    of graduation/completion rates and expected earnings after completed education. We use data envelopment analysis (DEA) to compare (benchmark) the Nordic countries with a relevant group of rich OECD countries and calculate input efficiency scores for each country. We estimate a wide range of specifications...... in order to analyse different aspects of efficiency. In purely quantitative models (where inputs and outputs are expenditure and number of students at different levels of the educational system) and in models where graduation or completion rates are included as indicators of output quality, Finland...... is the most efficient Nordic country (often fully efficient), whereas Sweden and especially Norway and Denmark are clearly inefficient. However, using PISA test scores as indicators of student input quality in upper secondary education reduces the inefficiencies of these three countries. Also, when expected...

  1. Efficiency principles of consulting entrepreneurship

    OpenAIRE

    Moroz Yustina S.; Drozdov Igor N.

    2015-01-01

    The article reviews the primary goals and problems of consulting entrepreneurship. The principles defining efficiency of entrepreneurship in the field of consulting are generalized. The special attention is given to the importance of ethical principles of conducting consulting entrepreneurship activity.

  2. Planning for resource efficient cities

    DEFF Research Database (Denmark)

    Fertner, Christian; Groth, Niels Boje

    2016-01-01

    development from energy consumption are crucial for a city’s future vulnerability and resilience against changes in general resource availability. The challenge gets further complex, as resource and energy efficiency in a city is deeply interwoven with other aspects of urban development such as social...... structures and the geographical context. As cities are the main consumer of energy and resources, they are both problem and solution to tackle issues of energy efficiency and saving. Cities have been committed to this agenda, especially to meet the national and international energy targets. Increasingly......, cities act as entrepreneurs of new energy solutions acknowledging that efficient monitoring of energy and climate policies has become important to urban branding and competitiveness. This special issue presents findings from the European FP7 project ‘Planning for Energy Efficient Cities’ (PLEEC...

  3. Energy efficiency: utopia or reality?

    International Nuclear Information System (INIS)

    Anon.

    2006-01-01

    In its 2006 allocution the world council on the energy WEC, analyzes the role of the energy efficiency in the energy life cycle. In spite of different objectives followed by the developing and developed countries, implement a world energy efficiency economy is a challenge possible by the cooperation.The WEC is an ideal forum for the information and experience exchange. (A.L.B.)

  4. Efficient computation of argumentation semantics

    CERN Document Server

    Liao, Beishui

    2013-01-01

    Efficient Computation of Argumentation Semantics addresses argumentation semantics and systems, introducing readers to cutting-edge decomposition methods that drive increasingly efficient logic computation in AI and intelligent systems. Such complex and distributed systems are increasingly used in the automation and transportation systems field, and particularly autonomous systems, as well as more generic intelligent computation research. The Series in Intelligent Systems publishes titles that cover state-of-the-art knowledge and the latest advances in research and development in intelligen

  5. Energy end-use efficiency

    OpenAIRE

    Jochem, E.

    2000-01-01

    Since the 1970s more efficient energy use in OECD countries has weakened or eliminated the link between economic growth and energy use. At the global level just 37 percent of primary energy is converted to useful energy - meaning that nearly two-thirds is lost. the next 20 years percent in most industrialised countries and more than 40 percent transition economies. Dematerialization and recycling will further reduce energy intensity. Thus energy efficiency is one of the main technological dri...

  6. Energy management and energy efficiency

    International Nuclear Information System (INIS)

    Anon.

    2013-01-01

    This bibliographical note presents an official publication which contains the latest standards and standard projects dealing with energy audits (general requirements, buildings, process, transport) as well as energy efficiency (definitions and requirements, benchmarking methodology) and energy management and its terminology in relationship with the new European directive 2012/27/UE on energy efficiency. Regulatory texts associated with the national and European energy policies are also proposed

  7. Energy Efficient Hydraulic Hybrid Drives

    OpenAIRE

    Rydberg, Karl-Erik

    2009-01-01

    Energy efficiency of propulsion systems for cars, trucks and construction machineries has become one of the most important topics in today’s mobile system design, mainly because of increased fuel costs and new regulations about engine emissions, which is needed to save the environment. To meet the increased requirements on higher efficiency and better functionality, components and systems have been developed over the years. For the last ten years the development of hybrid systems can be divid...

  8. Energy Efficient Drivepower: An Overview.

    Energy Technology Data Exchange (ETDEWEB)

    Ula, Sadrul; Birnbaum, Larry E.; Jordan, Don

    1993-05-01

    This report examines energy efficiency in drivepower systems. Only systems where the prime movers are electrical motors are discussed. A systems approach is used to examine all major aspects of drivepower, including motors, controls, electrical tune-ups, mechanical efficiency, maintenance, and management. Potential annual savings to the US society of $25 to $50 billion are indicated. The report was written for readers with a semi-technical background.

  9. Dioscin inhibits colon tumor growth and tumor angiogenesis through regulating VEGFR2 and AKT/MAPK signaling pathways

    Energy Technology Data Exchange (ETDEWEB)

    Tong, Qingyi [Regenerative Medicine Research Center, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041 (China); Qing, Yong, E-mail: qingyongxy@yahoo.co.jp [Department of Pharmacology, West China School of Pharmacy, Sichuan University, Chengdu, Sichuan 610041 (China); Wu, Yang [State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041 (China); Hu, Xiaojuan; Jiang, Lei [Department of Pharmacology, West China School of Pharmacy, Sichuan University, Chengdu, Sichuan 610041 (China); Wu, Xiaohua, E-mail: wuxh@scu.edu.cn [Regenerative Medicine Research Center, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041 (China)

    2014-12-01

    Dioscin has shown cytotoxicity against cancer cells, but its in vivo effects and the mechanisms have not elucidated yet. The purpose of the current study was to assess the antitumor effects and the molecular mechanisms of dioscin. We showed that dioscin could inhibit tumor growth in vivo and has no toxicity at the test condition. The growth suppression was accompanied by obvious blood vessel decrease within solid tumors. We also found dioscin treatment inhibited the proliferation of cancer and endothelial cell lines, and most sensitive to primary cultured human umbilical vein endothelial cells (HUVECs). What's more, analysis of HUVECs migration, invasion, and tube formation exhibited that dioscin has significantly inhibitive effects to these actions. Further analysis of blood vessel formation in the matrigel plugs indicated that dioscin could inhibit VEGF-induced blood vessel formation in vivo. We also identified that dioscin could suppress the downstream protein kinases of VEGFR2, including Src, FAK, AKT and Erk1/2, accompanied by the increase of phosphorylated P38MAPK. The results potently suggest that dioscin may be a potential anticancer drug, which efficiently inhibits angiogenesis induced by VEGFR2 signaling pathway as well as AKT/MAPK pathways. - Highlights: • Dioscin inhibits tumor growth in vivo and does not exhibit any toxicity. • Dioscin inhibits angiogenesis within solid tumors. • Dioscin inhibits the proliferation, migration, invasion, and tube formation of HUVECs. • Dioscin inhibits VEGF–induced blood vessel formation in vivo. • Dioscin inhibits VEGFR2 signaling pathway as well as AKT/MAPK pathway.

  10. Kaempferol Identified by Zebrafish Assay and Fine Fractionations Strategy from Dysosma versipellis Inhibits Angiogenesis through VEGF and FGF Pathways

    Science.gov (United States)

    Liang, Fang; Han, Yuxiang; Gao, Hao; Xin, Shengchang; Chen, Shaodan; Wang, Nan; Qin, Wei; Zhong, Hanbing; Lin, Shuo; Yao, Xinsheng; Li, Song

    2015-01-01

    Natural products are a rich resource for the discovery of therapeutic substances. By directly using 504 fine fractions from isolated traditional Chinese medicine plants, we performed a transgenic zebrafish based screen for anti-angiogenesis substances. One fraction, DYVE-D3, was found to inhibit the growth of intersegmental vessels in the zebrafish vasculature. Bioassay-guided isolation of DYVE-D3 indicates that the flavonoid kaempferol was the active substance. Kaempferol also inhibited the proliferation and migration of HUVECs in vitro. Furthermore, we found that kaempferol suppressed angiogenesis through inhibiting VEGFR2 expression, which can be enhanced by FGF inhibition. In summary, this study shows that the construction of fine fraction libraries allows efficient identification of active substances from natural products. PMID:26446489

  11. Advanced high efficiency concentrator cells

    Energy Technology Data Exchange (ETDEWEB)

    Gale, R. (Varian Associates, Inc., Palo Alto, CA (United States). Varian Research Center)

    1992-06-01

    This report describes research to develop the technology needed to demonstrate a monolithic, multijunction, two-terminal, concentrator solar cell with a terrestrial power conversion efficiency greater than 35%. Under three previous subcontracts, Varian developed many of the aspects of a technology needed to fabricate very high efficiency concentrator cells. The current project was aimed at exploiting the new understanding of high efficiency solar cells. Key results covered in this report are as follows. (1) A 1.93-eV AlGaAs/1.42-eV GaAs metal-interconnected cascade cell was manufactured with a one-sun efficiency at 27.6% at air mass 1.5 (AM1.5) global. (2) A 1.0eV InGaAs cell was fabricated on the reverse'' side of a low-doped GaAs substrate with a one-sun efficiency of 2.5% AM1.5 diffuse and a short-circuit current of 14.4 mA/cm{sup 2}. (3) Small-scale manufacturing of GaAs p/n concentrator cells was attempted and obtained an excellent yield of high-efficiency cells. (4) Grown-in tunnel junction cell interconnects that are transparent and thermally stable using C and Si dopants were developed. 10 refs.

  12. Transformer Efficiency Assessment - Okinawa, Japan

    Energy Technology Data Exchange (ETDEWEB)

    Thomas L. Baldwin; Robert J. Turk; Kurt S. Myers; Jake P. Gentle; Jason W. Bush

    2012-05-01

    The US Army Engineering & Support Center, Huntsville (USAESCH), and the US Marine Corps Base (MCB), Okinawa, Japan retained Idaho National Laboratory (INL) to conduct a Transformer Efficiency Assessment of “key” transformers located at multiple military bases in Okinawa, Japan. The purpose of this assessment is to support the Marine Corps Base, Okinawa in evaluating medium voltage distribution transformers for potential efficiency upgrades. The original scope of work included the MCB providing actual transformer nameplate data, manufacturer’s factory test sheets, electrical system data (kWh), demand data (kWd), power factor data, and electricity cost data. Unfortunately, the MCB’s actual data is not available and therefore making it necessary to de-scope the original assessment. Note: Any similar nameplate data, photos of similar transformer nameplates, and basic electrical details from one-line drawings (provided by MCB) are not a replacement for actual load loss test data. It is recommended that load measurements are performed on the high and low sides of transformers to better quantify actual load losses, demand data, and power factor data. We also recommend that actual data, when available, be inserted by MCB Okinawa where assumptions have been made and then the LCC analysis updated. This report covers a generalized assessment of modern U.S. transformers in a three level efficiency category, Low-Level efficiency, Medium-Level efficiency, and High-Level efficiency.

  13. Transformer Efficiency Assessment - Okinawa, Japan

    Energy Technology Data Exchange (ETDEWEB)

    Thomas L. Baldwin; Robert J. Turk; Kurt S. Myers; Jake P. Gentle; Jason W. Bush

    2012-08-01

    The US Army Engineering & Support Center, Huntsville (USAESCH), and the US Marine Corps Base (MCB), Okinawa, Japan retained Idaho National Laboratory (INL) to conduct a Transformer Efficiency Assessment of “key” transformers located at multiple military bases in Okinawa, Japan. The purpose of this assessment is to support the Marine Corps Base, Okinawa in evaluating medium voltage distribution transformers for potential efficiency upgrades. The original scope of work included the MCB providing actual transformer nameplate data, manufacturer’s factory test sheets, electrical system data (kWh), demand data (kWd), power factor data, and electricity cost data. Unfortunately, the MCB’s actual data is not available and therefore making it necessary to de-scope the original assessment. Note: Any similar nameplate data, photos of similar transformer nameplates, and basic electrical details from one-line drawings (provided by MCB) are not a replacement for actual load loss test data. It is recommended that load measurements are performed on the high and low sides of transformers to better quantify actual load losses, demand data, and power factor data. We also recommend that actual data, when available, be inserted by MCB Okinawa where assumptions have been made and then the LCC analysis updated. This report covers a generalized assessment of modern U.S. transformers in a three level efficiency category, Low-Level efficiency, Medium-Level efficiency, and High-Level efficiency.

  14. Polyphosphates inhibit extracellular matrix mineralization in MC3T3-E1 osteoblast cultures.

    Science.gov (United States)

    Hoac, Betty; Kiffer-Moreira, Tina; Millán, José Luis; McKee, Marc D

    2013-04-01

    Studies on various compounds of inorganic phosphate, as well as on organic phosphate added by post-translational phosphorylation of proteins, all demonstrate a central role for phosphate in biomineralization processes. Inorganic polyphosphates are chains of orthophosphates linked by phosphoanhydride bonds that can be up to hundreds of orthophosphates in length. The role of polyphosphates in mammalian systems, where they are ubiquitous in cells, tissues and bodily fluids, and are at particularly high levels in osteoblasts, is not well understood. In cell-free systems, polyphosphates inhibit hydroxyapatite nucleation, crystal formation and growth, and solubility. In animal studies, polyphosphate injections inhibit induced ectopic calcification. While recent work has proposed an integrated view of polyphosphate function in bone, little experimental data for bone are available. Here we demonstrate in osteoblast cultures producing an abundant collagenous matrix that normally show robust mineralization, that two polyphosphates (PolyP5 and PolyP65, polyphosphates of 5 and 65 phosphate residues in length) are potent mineralization inhibitors. Twelve-day MC3T3-E1 osteoblast cultures with added ascorbic acid (for collagen matrix assembly) and β-glycerophosphate (a source of phosphate for mineralization) were treated with either PolyP5 or PolyP65. Von Kossa staining and calcium quantification revealed that mineralization was inhibited in a dose-dependent manner by both polyphosphates, with complete mineralization inhibition at 10μM. Cell proliferation and collagen assembly were unaffected by polyphosphate treatment, indicating that polyphosphate inhibition of mineralization results not from cell and matrix effects but from direct inhibition of mineralization. This was confirmed by showing that PolyP5 and PolyP65 bound to synthetic hydroxyapatite in a concentration-dependent manner. Tissue-nonspecific alkaline phosphatase (TNAP, ALPL) efficiently hydrolyzed the two PolyPs as

  15. An extract of Uncaria tomentosa inhibiting cell division and NF-kappa B activity without inducing cell death.

    Science.gov (United States)

    Akesson, Christina; Lindgren, Hanna; Pero, Ronald W; Leanderson, Tomas; Ivars, Fredrik

    2003-12-01

    Previous reports have demonstrated that extracts of the plant Uncaria tomentosa inhibit tumor cell proliferation and inflammatory responses. We have confirmed that C-Med 100, a hot water extract of this plant, inhibits tumor cell proliferation albeit with variable efficiency. We extend these findings by showing that this extract also inhibits proliferation of normal mouse T and B lymphocytes and that the inhibition is not caused by toxicity or by induction of apoptosis. Further, the extract did not interfere with IL-2 production nor IL-2 receptor signaling. Since there was no discrete cell cycle block in C-Med 100-treated cells, we propose that retarded cell cycle progression caused the inhibition of proliferation. Collectively, these data suggested interference with a common pathway controlling cell growth and cell cycle progression. Indeed, we provide direct evidence that C-Med 100 inhibits nuclear factor kappa B (NF-kappa B) activity and propose that this at least partially causes the inhibition of proliferation.

  16. Salinomycin, a polyether ionophoric antibiotic, inhibits adipogenesis

    International Nuclear Information System (INIS)

    Szkudlarek-Mikho, Maria; Saunders, Rudel A.; Yap, Sook Fan; Ngeow, Yun Fong; Chin, Khew-Voon

    2012-01-01

    Highlights: ► Salinomycin inhibits preadipocyte differentiation into adipocytes. ► Salinomycin inhibits transcriptional regulation of adipogenesis. ► Pharmacological effects of salinomycin suggest toxicity in cancer therapy. -- Abstract: The polyether ionophoric antibiotics including monensin, salinomycin, and narasin, are widely used in veterinary medicine and as food additives and growth promoters in animal husbandry including poultry farming. Their effects on human health, however, are not fully understood. Recent studies showed that salinomycin is a cancer stem cell inhibitor. Since poultry consumption has risen sharply in the last three decades, we asked whether the consumption of meat tainted with growth promoting antibiotics might have effects on adipose cells. We showed in this report that the ionophoric antibiotics inhibit the differentiation of preadipocytes into adipocytes. The block of differentiation is not due to the induction of apoptosis nor the inhibition of cell proliferation. In addition, salinomycin also suppresses the transcriptional activity of the CCAAT/enhancer binding proteins and the peroxisome proliferator-activated receptor γ. These results suggest that the ionophoric antibiotics can be exploited as novel anti-obesity therapeutics and as pharmacological probes for the study of adipose biology. Further, the pharmacological effects of salinomycin could be a harbinger of its toxicity on the adipose tissue and other susceptible target cells in cancer therapy.

  17. Nickel Inhibits Mitochondrial Fatty Acid Oxidation

    Science.gov (United States)

    Uppala, Radha; McKinney, Richard W.; Brant, Kelly A.; Fabisiak, James P.; Goetzman, Eric S.

    2015-01-01

    Nickel exposure is associated with changes in cellular energy metabolism which may contribute to its carcinogenic properties. Here, we demonstrate that nickel strongly represses mitochondrial fatty acid oxidation—the pathway by which fatty acids are catabolized for energy—in both primary human lung fibroblasts and mouse embryonic fibroblasts. At the concentrations used, nickel suppresses fatty acid oxidation without globally suppressing mitochondrial function as evidenced by increased glucose oxidation to CO2. Pre-treatment with L-carnitine, previously shown to prevent nickel-induced mitochondrial dysfunction in neuroblastoma cells, did not prevent the inhibition of fatty acid oxidation. The effect of nickel on fatty acid oxidation occurred only with prolonged exposure (>5 hr), suggesting that direct inhibition of the active sites of metabolic enzymes is not the mechanism of action. Nickel is a known hypoxia-mimetic that activates hypoxia inducible factor-1α (HIF1α). Nickel-induced inhibition of fatty acid oxidation was blunted in HIF1α knockout fibroblasts, implicating HIF1α as one contributor to the mechanism. Additionally, nickel down-regulated the protein levels of the key fatty acid oxidation enzyme very long-chain acyl-CoA dehydrogenase (VLCAD) in a dose-dependent fashion. In conclusion, inhibition of fatty acid oxidation by nickel, concurrent with increased glucose metabolism, represents a form of metabolic reprogramming that may contribute to nickel-induced carcinogenesis. PMID:26051273

  18. Inhibition of serum naphthylamidases by atopic allergens

    NARCIS (Netherlands)

    Berrens, L.

    1968-01-01

    Human serum hydrolyses the 2-naphthylamides of -lysine and -arginine. The enzymatic activity of the serum naphthylamidases is inhibited by atopic allergens and by protein-sugar conjugates carrying 1-deoxy-2-ketose residues attached to the -amino groups of lysine residues in their peptide moieties.

  19. Salinomycin, a polyether ionophoric antibiotic, inhibits adipogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Szkudlarek-Mikho, Maria; Saunders, Rudel A. [Department of Medicine, Biochemistry and Cancer Biology, Center for Diabetes and Endocrine Research, College of Medicine, University of Toledo, Toledo, OH 43614 (United States); Yap, Sook Fan [Faculty of Medicine and Health Sciences, Department of Pre-Clinical Sciences, University of Tunku Abdul Rahman (Malaysia); Ngeow, Yun Fong [Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603 (Malaysia); Chin, Khew-Voon, E-mail: khew-voon.chin@utoledo.edu [Department of Medicine, Biochemistry and Cancer Biology, Center for Diabetes and Endocrine Research, College of Medicine, University of Toledo, Toledo, OH 43614 (United States)

    2012-11-30

    Highlights: Black-Right-Pointing-Pointer Salinomycin inhibits preadipocyte differentiation into adipocytes. Black-Right-Pointing-Pointer Salinomycin inhibits transcriptional regulation of adipogenesis. Black-Right-Pointing-Pointer Pharmacological effects of salinomycin suggest toxicity in cancer therapy. -- Abstract: The polyether ionophoric antibiotics including monensin, salinomycin, and narasin, are widely used in veterinary medicine and as food additives and growth promoters in animal husbandry including poultry farming. Their effects on human health, however, are not fully understood. Recent studies showed that salinomycin is a cancer stem cell inhibitor. Since poultry consumption has risen sharply in the last three decades, we asked whether the consumption of meat tainted with growth promoting antibiotics might have effects on adipose cells. We showed in this report that the ionophoric antibiotics inhibit the differentiation of preadipocytes into adipocytes. The block of differentiation is not due to the induction of apoptosis nor the inhibition of cell proliferation. In addition, salinomycin also suppresses the transcriptional activity of the CCAAT/enhancer binding proteins and the peroxisome proliferator-activated receptor {gamma}. These results suggest that the ionophoric antibiotics can be exploited as novel anti-obesity therapeutics and as pharmacological probes for the study of adipose biology. Further, the pharmacological effects of salinomycin could be a harbinger of its toxicity on the adipose tissue and other susceptible target cells in cancer therapy.

  20. Probenazole treatment inhibits anthocyanins biosynthesis via ...

    African Journals Online (AJOL)

    It has been found that anthocyanins were accumulated in Arabidopsis under drought or salt stress. In this study, such accumulation was found to be inhibited by external applied probenazole (3-allyloxy-1, 2-benzisothiazole-1,1-dioxide, PBZ), which is the active ingredient in oryzemate used for the protection of rice from ...

  1. Insulin inhibits tissue factor expression in monocytes

    NARCIS (Netherlands)

    Gerrits, A. J.; Koekman, C. A.; Yildirim, C.; Nieuwland, R.; Akkerman, J. W. N.

    2009-01-01

    Summary Objectives: Platelets from healthy subjects are inhibited by insulin but type 2 diabetes mellitus (T2DM) platelets have become insulin-resistant which might explain their hyperactivity. In the present study we investigated whether monocytes are responsive to insulin. Methods and Results:

  2. Undecylenic Acid Inhibits Morphogenesis of Candida albicans

    OpenAIRE

    McLain, Nealoo; Ascanio, Rhoda; Baker, Carol; Strohaver, Robert A.; Dolan, Joseph W.

    2000-01-01

    Resilient liners are frequently used to treat denture stomatitis, a condition often associated with Candida albicans infections. Of 10 liners tested, 2 were found to inhibit the switch from the yeast form to hyphae and a third was found to stimulate this switch. The inhibitor was determined to be undecylenic acid.

  3. Undecylenic acid inhibits morphogenesis of Candida albicans.

    Science.gov (United States)

    McLain, N; Ascanio, R; Baker, C; Strohaver, R A; Dolan, J W

    2000-10-01

    Resilient liners are frequently used to treat denture stomatitis, a condition often associated with Candida albicans infections. Of 10 liners tested, 2 were found to inhibit the switch from the yeast form to hyphae and a third was found to stimulate this switch. The inhibitor was determined to be undecylenic acid.

  4. Illustrating Enzyme Inhibition Using Gibbs Energy Profiles

    Science.gov (United States)

    Bearne, Stephen L.

    2012-01-01

    Gibbs energy profiles have great utility as teaching and learning tools because they present students with a visual representation of the energy changes that occur during enzyme catalysis. Unfortunately, most textbooks divorce discussions of traditional kinetic topics, such as enzyme inhibition, from discussions of these same topics in terms of…

  5. Inhibition of Corneal Neovascularization by Hydrazinocurcumin

    African Journals Online (AJOL)

    This article previously published in Volume 15 Issue 2 of this journal in February 2016 has been retracted in line with the guidelines from the Committee on Publication Ethics (COPE, http://publicationethics.org/resources/guidelines). Retracted: Zhan W, Zhu J, Zhang Y. Inhibition of corneal neovascularization by ...

  6. Retracted: Inhibition of Corneal Neovascularization by ...

    African Journals Online (AJOL)

    This article previously published in Volume 15 Issue 2 of this journal in February 2016 has been retracted in line with the guidelines from the Committee on Publication Ethics (COPE, http://publicationethics.org/resources/guidelines). Retracted: Zhan W, Zhu J, Zhang Y. Inhibition of corneal neovascularization by ...

  7. Type IA topoisomerase inhibition by clamp closure.

    Science.gov (United States)

    Leelaram, Majety Naga; Bhat, Anuradha Gopal; Godbole, Adwait Anand; Bhat, Rajeshwari Subray; Manjunath, Ramanathapuram; Nagaraja, Valakunja

    2013-08-01

    Bacterial DNA topoisomerase I (topoI) catalyzes relaxation of negatively supercoiled DNA. The enzyme alters DNA topology through protein-operated DNA gate, switching between open and closed conformations during its reaction. We describe the mechanism of inhibition of Mycobacterium smegmatis and Mycobacterium tuberculosis topoI by monoclonal antibodies (mAbs) that bind with high affinity and inhibit at 10-50 nM concentration. Unlike other inhibitors of topoisomerases, the mAbs inhibited several steps of relaxation reaction, namely DNA binding, cleavage, strand passage, and enzyme-DNA dissociation. The enhanced religation of the cleaved DNA in presence of the mAb indicated closing of the enzyme DNA gate. The formation of enzyme-DNA heterocatenane in the presence of the mAbs as a result of closing the gate could be inferred by the salt resistance of the complex, visualized by atomic force microscopy and confirmed by fluorescence measurements. Locking the enzyme-DNA complex as a closed clamp restricted the movements of the DNA gate, affecting all of the major steps of the relaxation reaction. Enzyme trapped on DNA in closed clamp conformation formed roadblock for the elongating DNA polymerase. The unusual multistep inhibition of mycobacterial topoisomerases may facilitate lead molecule development, and the mAbs would also serve as valuable tools to probe the enzyme mechanism.

  8. Optimal decision making in neural inhibition models

    NARCIS (Netherlands)

    van Ravenzwaaij, D.; van der Maas, H.L.J.; Wagenmakers, E.-J.

    2012-01-01

    In their influential Psychological Review article, Bogacz, Brown, Moehlis, Holmes, and Cohen (2006) discussed optimal decision making as accomplished by the drift diffusion model (DDM). The authors showed that neural inhibition models, such as the leaky competing accumulator model (LCA) and the

  9. Inhibited interferon production after space flight

    Science.gov (United States)

    Sonnenfeld, G.; Gould, C. L.; Williams, J.; Mandel, A. D.

    1988-01-01

    Several studies have been performed in our laboratories indicating that interferon production may be impaired in rodents after space flight. Using an antiorthostatic suspension model that simulates some of the effects of microgravity seen during space flight, we have shown that interferon-alpha/beta production was inhibited. The inhibition was not due solely to the stress of suspension. The inhibited interferon production was transient, as suspended animals returned to normal caging recovered the ability to produce interferon. Antiorthostatic suspension of mice also resulted in a loss of resistance to infection with the diabetogenic strain of encephalomyocarditis virus, which correlated with the drop in interferon production. In rats flown in US Space Shuttle mission SL-3, interferon-gamma production was inhibited severely when spleen cells were challenged with concanavalin-A upon return to earth. In contrast, interleukin-3 production by these cells was normal. These results suggest that immune responses may be altered after antiorthostatic modeling or space flight, and the resistance to viral infections may be especially affected.

  10. Inhibiting Translation One Protein at a Time.

    Science.gov (United States)

    Disney, Matthew D

    2017-06-01

    Historically, translational inhibitors have been confined to anti-bacterials that globally affect translation. Lintner et al. demonstrate that small molecules can specifically inhibit translation of a single disease-associated protein by stalling the ribosome's nascent chain [1], opening up a new therapeutic strategy for 'undruggable' proteins. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Inhibition of barley grain germination by light

    NARCIS (Netherlands)

    Roth-Bejerano, N.; Meulen, R.M. van der; Wang, M.

    1996-01-01

    Intact grains of barley (Hordeum distichum cv. Triumph) germinated rapidly in the dark or when exposed to brief daily light breaks in the temperature range 15-25°C, although germination proceeded less rapidly at low temperatures. Prolonged illumination (16 h/day) or continuous light inhibited

  12. Inhibiting Intuitive Thinking in Mathematics Education

    Science.gov (United States)

    Thomas, Michael O. J.

    2015-01-01

    The papers in this issue describe recent collaborative research into the role of inhibition of intuitive thinking in mathematics education. This commentary reflects on this research from a mathematics education perspective and draws attention to some of the challenges that arise in collaboration between research fields with different cultures,…

  13. Inhibition of Lipopolysaccharide-Induced Neuroinflammatory Events ...

    African Journals Online (AJOL)

    mL) with an IC50 value of 0.08 μg/mL. Conclusion: Data from this study indicate that CCP extract attenuates neuroinflammatory responses in. LPS-activated BV-2 microglia by inhibiting excessive production of pro-inflammatory mediators such ...

  14. [The role of inhibition in obsessional-compulsive disorders].

    Science.gov (United States)

    Dupuy, M; Rouillon, F; Bungener, C

    2013-02-01

    and resolving ambiguous situations. Neurocognitive studies show that cingular anterior cortex and prefrontal lateral cortex are engaged in ambiguous and conflicting situations. These two regions are considered essential for inhibition of routine actions, adjustment to change and, more generally, for an efficient and flexible behaviour. Repetitive nature of verification rituals in OCD could be explained in terms of lack of relationship between two systems, leaving in action the one that regulates automatic activities. Therefore, the rituals are considered to be under particular influence of the system which, being in charge of automatic actions, has a deficit in disengagement. Another model of attention, described by Posner, gives a further explanation of OCD. Mental inhibition has the capacity to treat information, either by applying strategies to control it (i.e. trying not to remember an unpleasant event) or leaving it to automatic control (i.e. incapacity to experience an emotion in relation to a particular event). In this way, the effort to suppress an intrusive thought is considered as controlled and deliberate cognitive treatment of emotionally charged information. In OCD, in the context of heightened anxiety, the assumed negative valence of information would influence habitual suppression of thought during controlled treatment. As a result, controlled efforts to suppress obsessions in emotionally stressful situations, would lead to the production of repetitive thoughts, as controlled treatment of information has failed in this action. On a clinical and experimental level, these studies have led to a better understanding and conceptualization of OCD. In spite of some conflicting results, there are concordant data in favour of hypotheses of the role of sub-cortical and frontal regions and their function in inhibition/desinhibition implied in the onset and maintenance of OCD. Functional neuroimagery anomalies are also in favour of the role of sub

  15. Inhibition of Mild Copper Metal Corrosion in HNO3 Medium by Acid Extract of Azadirachta Indica Seed

    Directory of Open Access Journals (Sweden)

    T. V. Sangeetha

    2011-01-01

    Full Text Available Efficiency of acid extract of dry azadirachta indica seed as corrosion inhibitor for mild copper metal in various concentration of (1 N,2 N and 3N HNO3 medium was investigated in the present study. Experimental methods include weight loss, determination of corrosion rate, inhibition efficiency and phytochemical analysis was studied. The results indicate azadirachta indica seed to be a good corrosion inhibitor of a mixed type and having efficiency as high as 95% at 1% inhibitor concentration in different time duration.

  16. Benefits for whom? Energy efficiency within the efficient market

    International Nuclear Information System (INIS)

    Chello, Dario

    2015-01-01

    How should the lack of an efficient energy market affect the design of energy efficiency policies and their implementation? What the consequences of an inefficient energy market on end users’ behaviour? This article tries to give an answer to such questions, by considering the decision making of domestic users following a few fundamental concepts of behavioural economics. The mechanism of price formation in the market, with particular reference to the internal energy market in Europe, will be examined and we will show that price remains the inflexible attribute in making an energy choice. Then, some conclusions will be addressed to policy makers on how to overcome the barriers illustrated.

  17. Neural synchrony during response production and inhibition.

    Directory of Open Access Journals (Sweden)

    Viktor Müller

    Full Text Available Inhibition of irrelevant information (conflict monitoring and/or of prepotent actions is an essential component of adaptive self-organized behavior. Neural dynamics underlying these functions has been studied in humans using event-related brain potentials (ERPs elicited in Go/NoGo tasks that require a speeded motor response to the Go stimuli and withholding a prepotent response when a NoGo stimulus is presented. However, averaged ERP waveforms provide only limited information about the neuronal mechanisms underlying stimulus processing, motor preparation, and response production or inhibition. In this study, we examine the cortical representation of conflict monitoring and response inhibition using time-frequency analysis of electroencephalographic (EEG recordings during continuous performance Go/NoGo task in 50 young adult females. We hypothesized that response inhibition would be associated with a transient boost in both temporal and spatial synchronization of prefrontal cortical activity, consistent with the role of the anterior cingulate and lateral prefrontal cortices in cognitive control. Overall, phase synchronization across trials measured by Phase Locking Index and phase synchronization between electrode sites measured by Phase Coherence were the highest in the Go and NoGo conditions, intermediate in the Warning condition, and the lowest under Neutral condition. The NoGo condition was characterized by significantly higher fronto-central synchronization in the 300-600 ms window, whereas in the Go condition, delta- and theta-band synchronization was higher in centro-parietal regions in the first 300 ms after the stimulus onset. The present findings suggest that response production and inhibition is supported by dynamic functional networks characterized by distinct patterns of temporal and spatial synchronization of brain oscillations.

  18. WEE1 inhibition sensitizes osteosarcoma to radiotherapy

    International Nuclear Information System (INIS)

    PosthumaDeBoer, Jantine; Würdinger, Thomas; Graat, Harm CA; Beusechem, Victor W van; Helder, Marco N; Royen, Barend J van; Kaspers, Gertjan JL

    2011-01-01

    The use of radiotherapy in osteosarcoma (OS) is controversial due to its radioresistance. OS patients currently treated with radiotherapy generally are inoperable, have painful skeletal metastases, refuse surgery or have undergone an intralesional resection of the primary tumor. After irradiation-induced DNA damage, OS cells sustain a prolonged G 2 cell cycle checkpoint arrest allowing DNA repair and evasion of cell death. Inhibition of WEE1 kinase leads to abrogation of the G 2 arrest and could sensitize OS cells to irradiation induced cell death. WEE1 expression in OS was investigated by gene-expression data analysis and immunohistochemistry of tumor samples. WEE1 expression in OS cell lines and human osteoblasts was investigated by Western blot. The effect of WEE1 inhibition on the radiosensitivity of OS cells was assessed by cell viability and caspase activation analyses after combination treatment. The presence of DNA damage was visualized using immunofluorescence microscopy. Cell cycle effects were investigated by flow cytometry and WEE1 kinase regulation was analyzed by Western blot. WEE1 expression is found in the majority of tested OS tissue samples. Small molecule drug PD0166285 inhibits WEE1 kinase activity. In the presence of WEE1-inhibitor, irradiated cells fail to repair their damaged DNA, and show higher levels of caspase activation. The inhibition of WEE1 effectively abrogates the irradiation-induced G 2 arrest in OS cells, forcing the cells into premature, catastrophic mitosis, thus enhancing cell death after irradiation treatment. We show that PD0166285, a small molecule WEE1 kinase inhibitor, can abrogate the G 2 checkpoint in OS cells, pushing them into mitotic catastrophe and thus sensitizing OS cells to irradiation-induced cell death. This suggests that WEE1 inhibition may be a promising strategy to enhance the radiotherapy effect in patients with OS

  19. Polysulfonate suramin inhibits Zika virus infection.

    Science.gov (United States)

    Tan, Chee Wah; Sam, I-Ching; Chong, Wei Lim; Lee, Vannajan Sanghiran; Chan, Yoke Fun

    2017-07-01

    Zika virus (ZIKV) is an arthropod-borne flavivirus that causes newborn microcephaly and Guillian-Barré syndrome in adults. No therapeutics are available to treat ZIKV infection or other flaviviruses. In this study, we explored the inhibitory effect of glycosaminoglycans and analogues against ZIKV infection. Highly sulfated heparin, dextran sulfate and suramin significantly inhibited ZIKV infection in Vero cells. De-sulfated heparin analogues lose inhibitory effect, implying that sulfonate groups are critical for viral inhibition. Suramin, an FDA-approved anti-parasitic drug, inhibits ZIKV infection with 3-5 log 10  PFU viral reduction with IC 50 value of ∼2.5-5 μg/ml (1.93 μM-3.85 μM). A time-of-drug-addition study revealed that suramin remains potent even when administrated at 1-24 hpi. Suramin inhibits ZIKV infection by preventing viral adsorption, entry and replication. Molecular dynamics simulation revealed stronger interaction of suramin with ZIKV NS3 helicase than with the envelope protein. Suramin warrants further investigation as a potential antiviral candidate for ZIKV infection. Heparan sulfate (HS) is a cellular attachment receptor for multiple flaviviruses. However, no direct ZIKV-heparin interaction was observed in heparin-binding analysis, and downregulate or removal of cellular HS with sodium chlorate or heparinase I/III did not inhibit ZIKV infection. This indicates that cell surface HS is not utilized by ZIKV as an attachment receptor. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Enhancement of the Inhibitor Efficiency of Atropine Methochloride in Corrosion Control of Mild Steel in Sulphuric Acid

    Directory of Open Access Journals (Sweden)

    Abida Begum

    2008-01-01

    Full Text Available The inhibition efficiency and synergistic behaviour of 10-4 M Atropine methochloride was carried out using mass loss and polarisation methods in the presence of (i metal ions, Ni2+ and Cu2+ between 10-2 M to 10-6 M concentrations, (ii different concentrations of metal ions and 10-3 M I-, 10-3 M Cl- and 10-3 M Br- solutions and (iii different metal ions, 10-3M I- and at three different temperatures. The analysis reveals that the inhibition efficiency of Atropine methochloride was maximum at 10-2 M in 5 hours of immersion period. Halides decreased the corrosion rate of mild steel in Sulphuric acid. The decrease is maximum with 10-3 M I-. As the temperature increased from 298K to 308K, the inhibition efficiency gradually decreased. The inhibitor was found to be effective up to 303K

  1. Humid free efficient solar panel

    Science.gov (United States)

    Panjwani, Manoj Kumar; Panjwani, Suresh Kumar; Mangi, Fareed Hussain; Khan, Danish; Meicheng, Li

    2017-09-01

    The paper examines the impact of the humidity on the Solar panels which makes a space for the drastic variation in the power generated and makes the device less efficient. Humidity readily affects the efficiency of the solar cells and creates a minimal layer of water on its surface. It also decreases the efficiency by 10-20% of the total power output produced. Moreover, to handle this issue, all around characterized measures are required to be taken to guarantee the smooth working of the solar panels utilized in humid areas. In connection with this issue, Karachi, the biggest city of Pakistan which is located near the costal line touching Arabian Sea, was taken as a reference city to measure the humidity range. In Karachi, the average humidity lies between 25-70% (as per Pakistan Meteorological Department PMD), that indirectly leads in decreasing power acquired from a Solar Panel and develops various complexities for the solar system. The system on average experiences stability issues, such as those of power fluctuations etc., due to which, the whole solar system installed observes abnormal variations in acquired power. Silica Gel was used as a desiccant material in order to assure dryness over the solar panel. More than four experiments were conducted with the usage of water absorbent to improve the efficiency and to make system more power efficient.

  2. Improving efficiency in meat production.

    Science.gov (United States)

    Brameld, John M; Parr, Tim

    2016-08-01

    Selective breeding and improved nutritional management over the past 20-30 years has resulted in dramatic improvements in growth efficiency for pigs and poultry, particularly lean tissue growth. However, this has been achieved using high-quality feed ingredients, such as wheat and soya that are also used for human consumption and more recently biofuels production. Ruminants on the other hand are less efficient, but are normally fed poorer quality ingredients that cannot be digested by human subjects, such as grass or silage. The challenges therefore are to: (i) maintain the current efficiency of growth of pigs and poultry, but using more ingredients not needed to feed the increasing human population or for the production of biofuels; (ii) improve the efficiency of growth in ruminants; (iii) at the same time produce animal products (meat, milk and eggs) of equal or improved quality. This review will describe the use of: (a) enzyme additives for animal feeds, to improve feed digestibility; (b) known growth promoting agents, such as growth hormone, β-agonists and anabolic steroids, currently banned in the European Union but used in other parts of the world; (c) recent transcriptomic studies into molecular mechanisms for improved growth efficiency via low residual feed intake. In doing so, the use of genetic manipulation in animals will also be discussed.

  3. Mobilising Investment in Energy Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    Taxes, loans and grants, trading schemes and white certificates, public procurement and investment in R&D or infrastructure: known collectively as 'economic instruments', these tools can be powerful means of mobilising the finances needed to achieve policy goals by implementing energy efficiency measures. The role of economic instruments is to kick-start the private financial markets and to motivate private investors to fund EE measures. They should reinforce and promote energy performance regulations. This IEA analysis addresses the fact that, to date, relatively little effort has been directed toward evaluating how well economic instruments work. Using the buildings sector to illustrate how such measures can support energy efficiency, this paper can help policy makers better select and design economic instruments appropriate to their policy objectives and national contexts. This report’s three main aims are to: 1) Examine how economic instruments are currently used in energy efficiency policy; 2) Consider how economic instruments can be more effective and efficient in supporting low-energy buildings; and 3) Assess how economic instruments should be funded, where public outlay is needed. Detailed case studies in this report assess examples of economic instruments for energy efficiency in the buildings sector in Canada (grants), France (tax relief and loans), Germany (loans and grants), Ireland (grants) and Italy (white certificates and tax relief).

  4. Inhibition of phagocytic activity of ARPE-19 cells by free radical mediated oxidative stress.

    Science.gov (United States)

    Olchawa, Magdalena M; Pilat, Anna K; Szewczyk, Grzegorz M; Sarna, Tadeusz Jan

    2016-08-01

    Oxidative stress is a main factor responsible for key changes leading to the onset of age-related macular degeneration (ARMD) that occur in the retinal pigment epithelium (RPE), which is involved in phagocytosis of photoreceptor outer segments (POS). In this study, hydrogen peroxide (H2O2), H2O2 and iron ions (Fe) or rose Bengal (RB) in the presence of NADH and Fe were used to model free radical mediated oxidative stress to test if free radicals and singlet oxygen have different efficiency to inhibit phagocytosis of ARPE-19 cells. Free radical mediated oxidative stress was confirmed by HPLC-EC(Hg) measurements of cholesterol hydroperoxides in treated cells. Electron paramagnetic resonance (EPR) spin trapping was employed to detect superoxide anion. Cell survival was analyzed by the MTT assay. Specific phagocytosis of fluorescein-5-isothiocyanate-labeled POS and non-specific phagocytosis of fluorescent beads were measured by flow cytometry. HPLC analysis of cells photosensitized with RB in the presence of NADH and Fe indicated substantial increase in formation of free radical-dependent 7α/7β-hydroperoxides. EPR spin trapping confirmed the photogeneration of superoxide anion in samples enriched with RB, NADH and Fe. For all three protocols sub-lethal oxidative stress induced significant inhibition of the specific phagocytosis of POS. In contrast, non-specific phagocytosis was inhibited only by H2O2 or H2O2 and Fe treatment. Inhibition of phagocytosis was transient and recoverable by 24 h. These results suggest that free radicals may exert similar to singlet oxygen efficiency in inhibiting phagocytosis of RPE cells, and that the effect depends on the location where initial reactive species are formed.

  5. Lignans and norlignans inhibit multidrug resistance protein 1 (MRP1/ABCC1)-mediated transport.

    Science.gov (United States)

    Wróbel, Anna; Eklund, Patrik; Bobrowska-Hägerstrand, Malgorzata; Hägerstrand, Henry

    2010-11-01

    Multidrug resistance protein 1 (MRP1/ABCC1) is one of the drug efflux pumps mediating multidrug resistance in several cancer types. Efficient nontoxic inhibitors of MRP1-mediated transport are sought to potentially sensitise cancer cells to anticancer drugs. This study examined the potency of a series of plant lignans and norlignans of various structures to inhibit MRP1-mediated transport from human erythrocytes. The occurrence of MRP1 in the human erythrocyte membrane makes this cell a useful model in searching for efficient MRP1inhibitors. The inhibition of 2',7'-bis-(carboxypropyl)-5(6)-carboxyfluorescein (BCPCF) transport from human erythrocytes was measured fluorymetrically. In order to study possible membrane-perturbing effects of lignans and norlignans, the potency of these compounds to induce haemolysis, erythrocyte shape change, and phosphatidylserine (PS) exposure in the external layer of the erythrocyte membrane was examined. Nine compounds (six norlignans and three lignans) of the fourteen that were tested inhibited BCPCF transport from human erythrocytes. The most efficient inhibitor, the norlignan coded L1, had IC(50)=50 μM. Structure-activity relationship analysis showed that the strongest inhibitors were found among lignans and norlignans bearing a carbonyl function at position C-9. The highly oxidised structures and the presence of an ionisable group such as the carboxylic acid function enhance activity. All compounds that significantly decreased BCPCF transport were non-haemolytic, did not cause PS exposure and did not have any effect on erythrocyte shapes up to 200 μM. Lignans and norlignans can inhibit MRP1-mediated transport from human erythrocytes and should be further investigated as possible agents reversing multidrug resistance.

  6. From energy efficiency towards resource efficiency within the Ecodesign Directive

    DEFF Research Database (Denmark)

    Bundgaard, Anja Marie; Mosgaard, Mette; Remmen, Arne

    2017-01-01

    and dishwashers. The role of DG Environment in the Ecodesign Directive could be strengthen in order to include broader environ- mental aspects and drive the resource efficiency and circular economy agenda. A final recommendation is to continue to expand the work on developing standards defining test methods...

  7. Cleanroom Energy Efficiency Workshop Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Tschudi, Bill

    1999-03-15

    On March 15, 1999, Lawrence Berkeley National Laboratory hosted a workshop focused on energy efficiency in Cleanroom facilities. The workshop was held as part of a multiyear effort sponsored by the California Institute for Energy Efficiency, and the California Energy Commission. It is part of a project that concentrates on improving energy efficiency in Laboratory type facilities including cleanrooms. The project targets the broad market of laboratory and cleanroom facilities, and thus cross-cuts many different industries and institutions. This workshop was intended to raise awareness by sharing case study success stories, providing a forum for industry networking on energy issues, contributing LBNL expertise in research to date, determining barriers to implementation and possible solutions, and soliciting input for further research.

  8. Green corridor : energy efficiency initiatives

    Energy Technology Data Exchange (ETDEWEB)

    Bartlett, M.; Strickland, R.; Harding, N. [Windsor Univ., ON (Canada)

    2005-07-01

    This presentation discussed environmental sustainability using alternative energy technologies. It discussed Ecohouse, which is a house designed using conventional and inventive products and techniques to represent an eco-efficient model for living, a more sustainable house, demonstrating sustainable technologies in action and setting a new standard for resource efficiency in Windsor. The presentation provided a building analysis and discussed the following: geothermal heating; distributive power; green roof; net metering; grey water plumbing; solar water heating; passive lighting; energy efficient lighting and geothermal heating and cooling. It also discussed opportunities for innovation, namely: greenhouse; composting toilets; alternative insulation; net metering; solar arrays; hydroponics; and expansion of the house. Also discussed were a nature bridge, an underwater electric kite, and a vertically aerodynamic turbine. The benefits of renewable energy, small hydro power potential, and instream energy generation technology were presented. 9 refs., figs.

  9. GATE: Improving the computational efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Staelens, S. [UGent-ELIS, St-Pietersnieuwstraat, 41, B-9000 Gent (Belgium)]. E-mail: steven.staelens@ugent.be; De Beenhouwer, J. [UGent-ELIS, St-Pietersnieuwstraat, 41, B-9000 Gent (Belgium); Kruecker, D. [Institute of Medicine-Forschungszemtrum Juelich, D-52425 Juelich (Germany); Maigne, L. [Departement de Curietherapie-Radiotherapie, Centre Jean Perrin, F-63000 Clermont-Ferrand (France); Rannou, F. [Departamento de Ingenieria Informatica, Universidad de Santiago de Chile, Santiago (Chile); Ferrer, L. [INSERM U601, CHU Nantes, F-44093 Nantes (France); D' Asseler, Y. [UGent-ELIS, St-Pietersnieuwstraat, 41, B-9000 Gent (Belgium); Buvat, I. [INSERM U678 UPMC, CHU Pitie-Salpetriere, F-75634 Paris (France); Lemahieu, I. [UGent-ELIS, St-Pietersnieuwstraat, 41, B-9000 Gent (Belgium)

    2006-12-20

    GATE is a software dedicated to Monte Carlo simulations in Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET). An important disadvantage of those simulations is the fundamental burden of computation time. This manuscript describes three different techniques in order to improve the efficiency of those simulations. Firstly, the implementation of variance reduction techniques (VRTs), more specifically the incorporation of geometrical importance sampling, is discussed. After this, the newly designed cluster version of the GATE software is described. The experiments have shown that GATE simulations scale very well on a cluster of homogeneous computers. Finally, an elaboration on the deployment of GATE on the Enabling Grids for E-Science in Europe (EGEE) grid will conclude the description of efficiency enhancement efforts. The three aforementioned methods improve the efficiency of GATE to a large extent and make realistic patient-specific overnight Monte Carlo simulations achievable.

  10. GATE: Improving the computational efficiency

    International Nuclear Information System (INIS)

    Staelens, S.; De Beenhouwer, J.; Kruecker, D.; Maigne, L.; Rannou, F.; Ferrer, L.; D'Asseler, Y.; Buvat, I.; Lemahieu, I.

    2006-01-01

    GATE is a software dedicated to Monte Carlo simulations in Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET). An important disadvantage of those simulations is the fundamental burden of computation time. This manuscript describes three different techniques in order to improve the efficiency of those simulations. Firstly, the implementation of variance reduction techniques (VRTs), more specifically the incorporation of geometrical importance sampling, is discussed. After this, the newly designed cluster version of the GATE software is described. The experiments have shown that GATE simulations scale very well on a cluster of homogeneous computers. Finally, an elaboration on the deployment of GATE on the Enabling Grids for E-Science in Europe (EGEE) grid will conclude the description of efficiency enhancement efforts. The three aforementioned methods improve the efficiency of GATE to a large extent and make realistic patient-specific overnight Monte Carlo simulations achievable

  11. Efficiency of Capacitively Loaded Converters

    DEFF Research Database (Denmark)

    Andersen, Thomas; Huang, Lina; Andersen, Michael A. E.

    2012-01-01

    is introduced as a definition of efficiency. The calculated and measured efficiency curves for charging DEAP actuator, polypropylene film capacitor and X7R MLCC are provided and compared. The attention has to be paid for the voltage dependent capacitive load, like X7R MLCC, when evaluating the charging......This paper explores the characteristic of capacitance versus voltage for dielectric electro active polymer (DEAP) actuator, 2kV polypropylene film capacitor as well as 3kV X7R multi layer ceramic capacitor (MLCC) at the beginning. An energy efficiency for capacitively loaded converters...... polypropylene film capacitor can be the equivalent capacitive load. Because of the voltage dependent characteristic, X7R MLCC cannot be used to replace the DEAP actuator. However, this type of capacitor can be used to substitute the capacitive actuator with voltage dependent property at the development phase....

  12. Historical Analysis of Champion Photovoltaic Module Efficiencies

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, Sarah [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Repins, Ingrid L [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Metzger, Wyatt K [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Emery, Keith A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kazmerski, Lawrence L [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Levi, Dean H [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Tappan, Ian A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Verlinden, Pierre J. [Trina Solar; Huang, Susan [Mantech International; Bowden, Stuart [Arizona State University

    2018-02-14

    Champion photovoltaic (PV) cell and module efficiencies have been reported in Progress in PV since 1993. Following the evolution of these efficiencies enables researchers to track the progress of various technologies. National Renewable Energy Laboratory has maintained a historical chart of the champion cell efficiencies, but has not published a similar chart of champion module efficiencies. Here, we analyze champion module efficiencies and compare them to champion cell efficiencies to better understand technology trends over the last three decades, highlighting that, in some cases, module efficiencies exceed 90% of cell efficiencies. Recommendations are provided on how to change the data collection and reporting for champion efficiencies to increase the value of these records.

  13. Energy Efficiency in Future PONs

    DEFF Research Database (Denmark)

    Reschat, Halfdan; Laustsen, Johannes Russell; Wessing, Henrik

    2012-01-01

    There is a still increasing tendency to give energy efficiency a high priority, even in already low energy demanding systems. This is also the case for Passive Optical Networks (PONs) for which many different methods for saving energy are proposed. This paper uses simulations to evaluate three...... proposed power saving solutions for PONs which use sleep mechanisms for saving power. The discovered advantages and disadvantages of these methods are then used as a basis for proposing a new solution combining different techniques in order to increase the energy efficiency further. This novel solution...

  14. Information efficiency in visual communication

    Science.gov (United States)

    Alter-Gartenberg, Rachel; Rahman, Zia-Ur

    1993-01-01

    This paper evaluates the quantization process in the context of the end-to-end performance of the visual-communication channel. Results show that the trade-off between data transmission and visual quality revolves around the information in the acquired signal, not around its energy. Improved information efficiency is gained by frequency dependent quantization that maintains the information capacity of the channel and reduces the entropy of the encoded signal. Restorations with energy bit-allocation lose both in sharpness and clarity relative to restorations with information bit-allocation. Thus, quantization with information bit-allocation is preferred for high information efficiency and visual quality in optimized visual communication.

  15. Equol inhibits growth, induces atresia, and inhibits steroidogenesis of mouse antral follicles in vitro

    International Nuclear Information System (INIS)

    Mahalingam, Sharada; Gao, Liying; Gonnering, Marni; Helferich, William; Flaws, Jodi A.

    2016-01-01

    Equol is a non-steroidal estrogen metabolite produced by microbial conversion of daidzein, a major soy isoflavone, in the gut of some humans and many animal species. Isoflavones and their metabolites can affect endogenous estradiol production, action, and metabolism, potentially influencing ovarian follicle function. However, no studies have examined the effects of equol on intact ovarian antral follicles, which are responsible for sex steroid synthesis and further development into ovulatory follicles. Thus, the present study tested the hypothesis that equol inhibits antral follicle growth, increases follicle atresia, and inhibits steroidogenesis in the adult mouse ovary. To test this hypothesis, antral follicles isolated from adult CD-1 mice were cultured with vehicle control (dimethyl sulfoxide; DMSO) or equol (600 nM, 6 μM, 36 μM, and 100 μM) for 48 and 96 h. Every 24 h, follicle diameters were measured to monitor growth. At 48 and 96 h, the culture medium was subjected to measurement of hormone levels, and the cultured follicles were subjected to gene expression analysis. Additionally, follicles were histologically evaluated for signs of atresia after 96 h of culture. The results indicate that equol (100 μM) inhibited follicle growth, altered the mRNA levels of bcl2-associated X protein and B cell leukemia/lymphoma 2, and induced follicle atresia. Further, equol decreased the levels of estradiol, testosterone, androstenedione, and progesterone, and it decreased mRNA levels of cholesterol side-chain cleavage, steroid 17-α-hydroxalase, and aromatase. Collectively, these data indicate that equol inhibits growth, increases atresia, and inhibits steroidogenesis of cultured mouse antral follicles. - Highlights: • Equol exposure inhibits antral follicle growth. • Equol exposure increases follicle atresia. • Equol exposure inhibits sex steroid hormone levels. • Equol exposure inhibits mRNA levels of certain steroidogenic enzymes.

  16. Proactive modulation of long-interval intracortical inhibition during response inhibition

    Science.gov (United States)

    Cowie, Matthew J.; MacDonald, Hayley J.; Cirillo, John

    2016-01-01

    Daily activities often require sudden cancellation of preplanned movement, termed response inhibition. When only a subcomponent of a whole response must be suppressed (required here on Partial trials), the ensuing component is markedly delayed. The neural mechanisms underlying partial response inhibition remain unclear. We hypothesized that Partial trials would be associated with nonselective corticomotor suppression and that GABAB receptor-mediated inhibition within primary motor cortex might be responsible for the nonselective corticomotor suppression contributing to Partial trial response delays. Sixteen right-handed participants performed a bimanual anticipatory response inhibition task while single- and paired-pulse transcranial magnetic stimulation was delivered to elicit motor evoked potentials in the left first dorsal interosseous muscle. Lift times, amplitude of motor evoked potentials, and long-interval intracortical inhibition were examined across the different trial types (Go, Stop-Left, Stop-Right, Stop-Both). Go trials produced a tight distribution of lift times around the target, whereas those during Partial trials (Stop-Left and Stop-Right) were substantially delayed. The modulation of motor evoked potential amplitude during Stop-Right trials reflected anticipation, suppression, and subsequent reinitiation of movement. Importantly, suppression was present across all Stop trial types, indicative of a “default” nonselective inhibitory process. Compared with blocks containing only Go trials, inhibition increased when Stop trials were introduced but did not differ between trial types. The amount of inhibition was positively correlated with lift times during Stop-Right trials. Tonic levels of inhibition appear to be proactively modulated by task context and influence the speed at which unimanual responses occur after a nonselective “brake” is applied. PMID:27281744

  17. An Ecofriendly Initiative for the Corrosion Inhibition of Mild Steel in 1 M HCl Using Tecoma capensis Flower Extract

    OpenAIRE

    Prithiba, A.; Rajalakshmi, R.

    2016-01-01

    Corrosion inhibition of mild steel in 1 M HCl in the presence of Tecoma capensis flower extract was carried out by means of mass loss, potentiodynamic polarisation, and electrochemical impedance techniques. The inhibition efficiency varied with concentration of the inhibitor, immersion time, and temperature. The adsorption of the inhibitor on mild steel surface obeys Langmuir’s adsorption isotherm. Thermodynamic parameters reveal that the adsorption process is spontaneous. Electrochemical stu...

  18. Gene- and protein-delivered zinc finger-staphylococcal nuclease hybrid for inhibition of DNA replication of human papillomavirus.

    Science.gov (United States)

    Mino, Takashi; Mori, Tomoaki; Aoyama, Yasuhiro; Sera, Takashi

    2013-01-01

    Previously, we reported that artificial zinc-finger proteins (AZPs) inhibited virus DNA replication in planta and in mammalian cells by blocking binding of a viral replication protein to its replication origin. However, the replication mechanisms of viruses of interest need to be disentangled for the application. To develop more widely applicable methods for antiviral therapy, we explored the feasibility of inhibition of HPV-18 replication as a model system by cleaving its viral genome. To this end, we fused the staphylococcal nuclease cleaving DNA as a monomer to an AZP that binds to the viral genome. The resulting hybrid nuclease (designated AZP-SNase) cleaved its target DNA plasmid efficiently and sequence-specifically in vitro. Then, we confirmed that transfection with a plasmid expressing AZP-SNase inhibited HPV-18 DNA replication in transient replication assays using mammalian cells. Linker-mediated PCR analysis revealed that the AZP-SNase cleaved an HPV-18 ori plasmid around its binding site. Finally, we demonstrated that the protein-delivered AZP-SNase inhibited HPV-18 DNA replication as well and did not show any significant cytotoxicity. Thus, both gene- and protein-delivered hybrid nucleases efficiently inhibited HPV-18 DNA replication, leading to development of a more universal antiviral therapy for human DNA viruses.

  19. Thiolactomycin inhibits D-aspartate oxidase: a novel approach to probing the active site environment.

    Science.gov (United States)

    Katane, Masumi; Saitoh, Yasuaki; Hanai, Toshihiko; Sekine, Masae; Furuchi, Takemitsu; Koyama, Nobuhiro; Nakagome, Izumi; Tomoda, Hiroshi; Hirono, Shuichi; Homma, Hiroshi

    2010-10-01

    D-Aspartate oxidase (DDO) and D-amino acid oxidase (DAO) are flavin adenine dinucleotide (FAD)-containing flavoproteins that catalyze the oxidative deamination of D-amino acids. While several functionally and structurally important amino acid residues have been identified in the DAO protein, little is known about the structure-function relationships of DDO. In the search for a potent DDO inhibitor as a novel tool for investigating its structure-function relationships, a large number of biologically active compounds of microbial origin were screened for their ability to inhibit the enzymatic activity of mouse DDO. We discovered several compounds that inhibited the activity of mouse DDO, and one of the compounds identified, thiolactomycin (TLM), was then characterized and evaluated as a novel DDO inhibitor. TLM reversibly inhibited the activity of mouse DDO with a mixed type of inhibition more efficiently than meso-tartrate and malonate, known competitive inhibitors of mammalian DDOs. The selectivity of TLM was investigated using various DDOs and DAOs, and it was found that TLM inhibits not only DDO, but also DAO. Further experiments with apoenzymes of DDO and DAO revealed that TLM is most likely to inhibit the activities of DDO and DAO by competition with both the substrate and the coenzyme, FAD. Structural models of mouse DDO/TLM complexes supported this finding. The binding mode of TLM to DDO was validated further by site-directed mutagenesis of an active site residue, Arg-237. Collectively, our findings show that TLM is a novel, active site-directed DDO inhibitor that will be useful for elucidating the molecular details of the active site environment of DDO. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

  20. Theobromine inhibits sensory nerve activation and cough.

    Science.gov (United States)

    Usmani, Omar S; Belvisi, Maria G; Patel, Hema J; Crispino, Natascia; Birrell, Mark A; Korbonits, Márta; Korbonits, Dezso; Barnes, Peter J

    2005-02-01

    Cough is a common and protective reflex, but persistent coughing is debilitating and impairs quality of life. Antitussive treatment using opioids is limited by unacceptable side effects, and there is a great need for more effective remedies. The present study demonstrates that theobromine, a methylxanthine derivative present in cocoa, effectively inhibits citric acid-induced cough in guinea-pigs in vivo. Furthermore, in a randomized, double-blind, placebo-controlled study in man, theobromine suppresses capsaicin-induced cough with no adverse effects. We also demonstrate that theobromine directly inhibits capsaicin-induced sensory nerve depolarization of guinea-pig and human vagus nerve suggestive of an inhibitory effect on afferent nerve activation. These data indicate the actions of theobromine appear to be peripherally mediated. We conclude theobromine is a novel and promising treatment, which may form the basis for a new class of antitussive drugs.

  1. Direct renin inhibition in chronic kidney disease

    DEFF Research Database (Denmark)

    Persson, Frederik; Rossing, Peter; Parving, Hans-Henrik

    2013-01-01

    that renin inhibition could hold potential for improved treatment in patients with chronic kidney disease, with diabetic nephropathy as an obvious group of patients to investigate, as the activity of the renin-angiotensin-aldosterone system is enhanced in these patients and as there is an unmet need...... early as a beneficial effect was unlikely and there was an increased frequency of side effects. Also in non-diabetic kidney disease a few intervention studies have been carried out, but there is no ongoing hard outcome study. In this review we provide the current evidence for renin inhibition in chronic...... kidney disease by reporting of the studies published so far as well as perspective on the future possibilites....

  2. Methamphetamine inhibits antigen processing, presentation, and phagocytosis.

    Directory of Open Access Journals (Sweden)

    Zsolt Tallóczy

    2008-02-01

    Full Text Available Methamphetamine (Meth is abused by over 35 million people worldwide. Chronic Meth abuse may be particularly devastating in individuals who engage in unprotected sex with multiple partners because it is associated with a 2-fold higher risk for obtaining HIV and associated secondary infections. We report the first specific evidence that Meth at pharmacological concentrations exerts a direct immunosuppressive effect on dendritic cells and macrophages. As a weak base, Meth collapses the pH gradient across acidic organelles, including lysosomes and associated autophagic organelles. This in turn inhibits receptor-mediated phagocytosis of antibody-coated particles, MHC class II antigen processing by the endosomal-lysosomal pathway, and antigen presentation to splenic T cells by dendritic cells. More importantly Meth facilitates intracellular replication and inhibits intracellular killing of Candida albicans and Cryptococcus neoformans, two major AIDS-related pathogens. Meth exerts previously unreported direct immunosuppressive effects that contribute to increased risk of infection and exacerbate AIDS pathology.

  3. Inhibition of intestinal disaccharidase activity by pentoses

    DEFF Research Database (Denmark)

    Halschou-Jensen, Kia

    The current health problems regarding the obesity epidemic, development of type 2 diabetes mellitus (T2D) and cardiovascular disease are a major challenge for healthcare systems worldwide.No simple or unique cure has been documented to prevent or treat this major health problem regarding T2D...... on carbohydrate- ingesting enzymes activity in vitro and possible effects on human postprandial blood response. In paper 1 the effects of sugar beet polyphenols from molasses and the potential inhibition of sucrase activity in vitro, was investigated. Two different polyphenol-rich fractions from chromatographic...... separation of molasses from sugar beets and pure ferulic acid were tested. We found no effects of the two fractions of molasses. The pure ferulic acid indicated an inhibition of sucrase in vitr. Both in vitro and in vivo studies have investigated the effects of L-arabinose and D-xylose on carbohydrate...

  4. The Kinetics of Carrier Transport Inhibition

    DEFF Research Database (Denmark)

    Rosenberg, T.; Wilbrandt, Robert Walter

    1962-01-01

    The kinetical treatment of enzymatic carrier transports as given in previous communications has been extended to conditions of inhibition. Various possible types of inhibitors have been considered differing in the site of attack (enzyme or carrier), in the mode of action (competing...... and polyphloretinephosphate. The results of the analysis for these inhibitors indicate a substrate competitive mode of action. The effect of reversing the transport direction by interchanging the substrate concentration has been treated for the case of a non-penetrating substrate competitive inhibitor in the external medium...... with the substrate for the enzyme or the carrier or for both, competing with the carrier for the enzyme, or non-competitive) and in the ability of penetrating the membrane. Experiments are reported on the inhibition of glucose and fructose transport across the human red cell membrane by phlorizine, phloretine...

  5. The RAE and University Efficiency.

    Science.gov (United States)

    Mace, John

    2000-01-01

    Evaluates effects of the new British funding formula for universities, based on the research assessment exercise (RAE). Compares effects of the RAE on two contrasting universities and finds the RAE has dramatically affected university organization, teaching, and research. RAE may have increased efficiency in teaching and research but encourages…

  6. Efficient synthesis of substituted dihydrotetraazapentacenes.

    Science.gov (United States)

    Seillan, Claire; Brisset, Hugues; Siri, Olivier

    2008-09-18

    We describe a versatile and very efficient synthesis of previously unknown substituted 5,14-dihydro-5,7,12,14-tetraazapentacenes (DHTAPs). A structural study by NMR spectroscopy showed that the conjugated pi-system of the pentacyclic skeleton rearranges depending on the electronic effect of the substituent(s).

  7. Energy Efficiency Indicators Methodology Booklet

    Energy Technology Data Exchange (ETDEWEB)

    Sathaye, Jayant; Price, Lynn; McNeil, Michael; de la rue du Can, Stephane

    2010-05-01

    This Methodology Booklet provides a comprehensive review and methodology guiding principles for constructing energy efficiency indicators, with illustrative examples of application to individual countries. It reviews work done by international agencies and national government in constructing meaningful energy efficiency indicators that help policy makers to assess changes in energy efficiency over time. Building on past OECD experience and best practices, and the knowledge of these countries' institutions, relevant sources of information to construct an energy indicator database are identified. A framework based on levels of hierarchy of indicators -- spanning from aggregate, macro level to disaggregated end-use level metrics -- is presented to help shape the understanding of assessing energy efficiency. In each sector of activity: industry, commercial, residential, agriculture and transport, indicators are presented and recommendations to distinguish the different factors affecting energy use are highlighted. The methodology booklet addresses specifically issues that are relevant to developing indicators where activity is a major factor driving energy demand. A companion spreadsheet tool is available upon request.

  8. Efficient simulation of semiflexible polymers

    NARCIS (Netherlands)

    Panja, Deb; Barkema, Gerard T.; van Leeuwen, J. M. J.

    2015-01-01

    Using a recently developed bead-spring model for semiflexible polymers that takes into account their natural extensibility, we report an efficient algorithm to simulate the dynamics for polymers like double-stranded DNA (dsDNA) in the absence of hydrodynamic interactions. The dsDNA is modeled with

  9. Efficient GPS Position Determination Algorithms

    National Research Council Canada - National Science Library

    Nguyen, Thao Q

    2007-01-01

    ... differential GPS algorithm for a network of users. The stand-alone user GPS algorithm is a direct, closed-form, and efficient new position determination algorithm that exploits the closed-form solution of the GPS trilateration equations and works...

  10. Design-Efficiency in Security

    DEFF Research Database (Denmark)

    Yuksel, Ender; Nielson, Hanne Riis; Nielson, Flemming

    In this document, we present our applied results on balancing security and performance using a running example, which is based on sensor networks. These results are forming a basis for a new approach to balance security and performance, and therefore provide design-­efficiency of key updates. We...

  11. Energy sustainability: consumption, efficiency, and ...

    Science.gov (United States)

    One of the critical challenges in achieving sustainability is finding a way to meet the energy consumption needs of a growing population in the face of increasing economic prosperity and finite resources. According to ecological footprint computations, the global resource consumption began exceeding planetary supply in 1977 and by 2030, global energy demand, population, and gross domestic product are projected to greatly increase over 1977 levels. With the aim of finding sustainable energy solutions, we present a simple yet rigorous procedure for assessing and counterbalancing the relationship between energy demand, environmental impact, population, GDP, and energy efficiency. Our analyses indicated that infeasible increases in energy efficiency (over 100 %) would be required by 2030 to return to 1977 environmental impact levels and annual reductions (2 and 3 %) in energy demand resulted in physical, yet impractical requirements; hence, a combination of policy and technology approaches is needed to tackle this critical challenge. This work emphasizes the difficulty in moving toward energy sustainability and helps to frame possible solutions useful for policy and management. Based on projected energy consumption, environmental impact, human population, gross domestic product (GDP), and energy efficiency, for this study, we explore the increase in energy-use efficiency and the decrease in energy use intensity required to achieve sustainable environmental impact le

  12. Improving efficiency in pig production

    African Journals Online (AJOL)

    made, are that each system is 100% efficient, and that the levels of production have at least been achieved in some of the experimental work. No allowance has been made for any penalty which the processor may apply to the carcass, the assumption being entirely that the objective is to produce lean meat independently of ...

  13. EYES -- Energy Efficient Sensor Networks

    NARCIS (Netherlands)

    Havinga, Paul J.M.; Etalle, Sandro; Karl, Holger; Petrioli, Chiara; Zorzi, Michele; Kip, Harry; Lentsch, Thomas; Conti, M.; Giordano, S.; Gregori, E.; Olariu, S.

    The EYES project (IST-2001-34734) is a three years European research project on self-organizing and collaborative energy-efficient sensor networks. It will address the convergence of distributed information processing, wireless communications, and mobile computing. The goal of the project is to

  14. Efficient audio power amplification - challenges

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, Michael A.E.

    2005-07-01

    For more than a decade efficient audio power amplification has evolved and today switch-mode audio power amplification in various forms are the state-of-the-art. The technical steps that lead to this evolution are described and in addition many of the challenges still to be faced and where extensive research and development are needed is covered. (au)

  15. Budgeting for Efficiency and Effectiveness

    Science.gov (United States)

    Pereus, Steven C.

    2012-01-01

    For most districts, budgeting has become a cost-cutting exercise designed to close the gap between revenues and expenses. During this process, decision makers inherently assume that existing operations are efficient and effective--an assumption that is rarely validated by facts. Cutting programs and services balances budgets but does not…

  16. Homothetic Efficiency: Theory and Applications

    NARCIS (Netherlands)

    J. Heufer (Jan); Hjertstrand, P. (Per)

    2017-01-01

    textabstractWe provide a nonparametric revealed preference approach to demand analysis based on homothetic efficiency. Homotheticity is widely assumed (often implicitly) because it is a convenient and often useful restriction. However, this assumption is rarely tested, and data rarely satisfy

  17. Simple and Practical Efficiency Lessons

    Science.gov (United States)

    Kolpin, Van

    2018-01-01

    The derivation of conditions necessary for Pareto efficient production and exchange is a lesson frequently showcased in microeconomic theory textbooks. Traditional delivery of this lesson is, however, limited in its scope of application and can be unnecessarily convoluted. The author shows that the universe of application is greatly expanded and a…

  18. Efficiency of participation in planning

    Directory of Open Access Journals (Sweden)

    Ghada Farouk Hassan

    2011-06-01

    A comparison between the two processes will take place in order to indentify the participation activities and their real efficiency. The comparison will be focused on the parameter of participation realized in each case in order to find gaps that have negative effects and needs to be filled.

  19. Efficient Audio Power Amplification - Challenges

    DEFF Research Database (Denmark)

    Andersen, Michael Andreas E.

    2005-01-01

    For more than a decade efficient audio power amplification has evolved and today switch-mode audio power amplification in various forms are the state-of-the-art. The technical steps that lead to this evolution are described and in addition many of the challenges still to be faced and where...... extensive research and development are needed is covered....

  20. Testing for Stochastic Dominance Efficiency

    NARCIS (Netherlands)

    G.T. Post (Thierry); O. Linton; Y-J. Whang

    2005-01-01

    textabstractWe propose a new test of the stochastic dominance efficiency of a given portfolio over a class of portfolios. We establish its null and alternative asymptotic properties, and define a method for consistently estimating critical values. We present some numerical evidence that our

  1. Soap with increased deactivation efficiency

    International Nuclear Information System (INIS)

    Severa, J.; Knajfl, J.; Cmolik, J.

    1980-01-01

    The decontamination effect of new types of toilet soap was studied in experiments with rat skin contaminated with an aqueous solution of fission products (pH=2.6). Most suitable for decontamination are soaps containing complex-forming substances; 1 hour after contamination their decontamination efficiency was 94.9+-0.6%. (author)

  2. Efficiently learning simple timed automata

    NARCIS (Netherlands)

    Verwer, S.E.; De Weerdt, M.M.; Witteveen, C.

    2008-01-01

    We describe an efficient algorithm for learning deterministic real-time automata (DRTA) from positive data. This data can be obtained from observations of the process to be modeled. The DRTA model we learn from such data can be used reason and gain knowledge about realtime systems such as network

  3. Declining Efficiency in the Economy

    DEFF Research Database (Denmark)

    Nørgaard, Jørgen

    1995-01-01

    with a high material standard of living. Examples are presented as are suggestions for how to improve the efficiency. These improvements, however, have a tendency to reduce the gross domestic product and hence are conflicting with the conventional political goals of growing GDP....

  4. China's energy efficiency target 2010

    International Nuclear Information System (INIS)

    Yang Ming

    2008-01-01

    The Chinese government has set an ambitious target: reducing China's energy intensity by 20%, or 4.36% each year between 2006 and 2010 on the 2005 level. Real data showed that China missed its target in 2006, having reduced its energy intensity only by 1.3%. The objective of this study is to evaluate the feasibility and potential of the Chinese to achieve the target. This paper presents issues of macro-economy, population migration, energy savings, and energy efficiency policy measures to achieve the target. A top-down approach was used to analyse the relationship between the Chinese economic development and energy demand cycles and to identify the potentials of energy savings in sub-sectors of the Chinese economy. A number of factors that contribute to China's energy intensity are identified in a number of energy-intensive sectors. This paper concludes that China needs to develop its economy at its potential GDP growth rate; strengthen energy efficiency auditing, monitoring and verification; change its national economy from a heavy-industry-dominated mode to a light industry or a commerce-dominated mode; phase out inefficient equipment in industrial sectors; develop mass and fast railway transportation; and promote energy-efficient technologies at the end use. This paper transfers key messages to policy makers for designing their policy to achieve China's energy efficiency target

  5. Fermentation of lignocellulosic hydrolysates: Inhibition and detoxification

    Energy Technology Data Exchange (ETDEWEB)

    Palmqvist, E.

    1998-02-01

    The ethanol yield and productivity obtained during fermentation of lignocellulosic hydrolysates is decreased due to the presence of inhibiting compounds, such as weak acids, furans and phenolic compounds produced during hydrolysis. Evaluation of the effect of various biological, physical and chemical detoxification treatments by fermentation assays using Saccharomyces cerevisiae was used to characterise inhibitors. Inhibition of fermentation was decreased after removal of the non-volatile compounds, pre-fermentation by the filamentous fungus Trichoderma reesei, treatment with the lignolytic enzyme laccase, extraction with ether, and treatment with alkali. Yeast growth in lignocellulosic hydrolysates was inhibited below a certain fermentation pH, most likely due to high concentrations of undissociated weak acids. The effect of individual compounds were studied in model fermentations. Furfural is reduced to furfuryl alcohol by yeast dehydrogenases, thereby affecting the intracellular redox balance. As a result, acetaldehyde accumulated during furfural reduction, which most likely contributed to inhibition of growth. Acetic acid (10 g 1{sup -1}) and furfural (3 g 1{sup -1}) interacted antagonistically causing decreased specific growth rate, whereas no significant individual or interaction effects were detected by the lignin-derived compound 4-hydroxybenzoic acid (2 g 1{sup -1}). By maintaining a high cell mass density in the fermentor, the process was less sensitive to inhibitors affecting growth and to fluctuations in fermentation pH, and in addition the depletion rate of bioconvertible inhibitors was increased. A theoretical ethanol yield and high productivity was obtained in continuous fermentation of spruce hydrolysate when the cell mass concentration was maintained at a high level by applying cell recirculation 164 refs, 16 figs, 5 tabs

  6. Voriconazole Inhibits Melanization in Cryptococcus neoformans▿

    OpenAIRE

    Martinez, Luis R.; Ntiamoah, Patricia; Gácser, Attila; Casadevall, Arturo; Nosanchuk, Joshua D.

    2007-01-01

    Voriconazole is a triazole antifungal drug that inhibits ergosterol synthesis and has broad activity against yeast and molds. While studying the interaction of voriconazole and Cryptococcus neoformans, we noted that cells grown in the presence of subinhibitory concentrations of voriconazole reduced melanin pigmentation. We investigated this effect systematically by assessing melanin production in the presence of voriconazole, amphotericin B, caspofungin, itraconazole, and fluconazole. Only vo...

  7. Theoretical and experimental studies of thermolysin inhibition

    OpenAIRE

    Wuxiuer, Yimingjiang

    2008-01-01

    Zinc-metalloproteinases play a key role in the biosythesis and metabolism of different bioactive peptides. As a member of zinc-metalloproteinases, thermolysin has served as a model system to study the inhibition mechanism of other metalloproteinases. Inhibitors of thermolysin have considerable potential as therapeutic agents. In the present master thesis, docking calculations were performed and reported for 25 potent non-peptidal thermolysin inhibitors retrieved from literatures. Docking sof...

  8. Extinction Generates Outcome-Specific Conditioned Inhibition.

    Science.gov (United States)

    Laurent, Vincent; Chieng, Billy; Balleine, Bernard W

    2016-12-05

    Extinction involves altering a previously established predictive relationship between a cue and its outcome by repeatedly presenting that cue alone. Although it is widely accepted that extinction generates some form of inhibitory learning [1-4], direct evidence for this claim has been lacking, and the nature of the associative changes induced by extinction have, therefore, remained a matter of debate [5-8]. In the current experiments, we used a novel behavioral approach that we recently developed and that provides a direct measure of conditioned inhibition [9] to compare the influence of extinguished and non-extinguished cues on choice between goal-directed actions. Using this approach, we provide direct evidence that extinction generates outcome-specific conditioned inhibition. Furthermore, we demonstrate that this inhibitory learning is controlled by the infralimbic cortex (IL); inactivation of the IL using M4 DREADDs abolished outcome-specific inhibition and rendered the cue excitatory. Importantly, we found that context modulated this inhibition. Outside its extinction context, the cue was excitatory and functioned as a specific predictor of its previously associated outcome, biasing choice toward actions earning the same outcome. In its extinction context, however, the cue acted as a specific inhibitor and biased choice toward actions earning different outcomes. Context modulation of these excitatory and inhibitory memories was mediated by the dorsal hippocampus (HPC), suggesting that the HPC and IL act in concert to control the influence of conditioned inhibitors on choice. These findings demonstrate for the first time that extinction turns a cue into a net inhibitor that can influence choice via counterfactual action-outcome associations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Erasing sensorimotor memories via PKMzeta inhibition.

    OpenAIRE

    Lee Michael von Kraus; Todd Charlton Sacktor; Joseph Thachil Francis

    2010-01-01

    Sensorimotor cortex has a role in procedural learning. Previous studies suggested that this learning is subserved by long-term potentiation (LTP), which is in turn maintained by the persistently active kinase, protein kinase Mzeta (PKMzeta). Whereas the role of PKMzeta in animal models of declarative knowledge is established, its effect on procedural knowledge is not well understood. Here we show that PKMzeta inhibition, via injection of zeta inhibitory peptide (ZIP) into the rat sensorimotor...

  10. Fermented Broth in Tyrosinase- and Melanogenesis Inhibition

    OpenAIRE

    Chin-Feng Chan; Ching-Cheng Huang; Ming-Yuan Lee; Yung-Sheng Lin

    2014-01-01

    Fermented broth has a long history of applications in the food, pharmaceutical and cosmetic industries. Recently, the use of fermented broth in skin care products is in ascendance. This review investigates the efficacy of fermented broth in inhibiting tyrosinase and melanogenesis. Possible active ingredients and hypopigmentation mechanisms of fermented broth are discussed, and potential applications of fermented broth in the cosmetic industry are also addressed.

  11. Fermented Broth in Tyrosinase- and Melanogenesis Inhibition

    Directory of Open Access Journals (Sweden)

    Chin-Feng Chan

    2014-08-01

    Full Text Available Fermented broth has a long history of applications in the food, pharmaceutical and cosmetic industries. Recently, the use of fermented broth in skin care products is in ascendance. This review investigates the efficacy of fermented broth in inhibiting tyrosinase and melanogenesis. Possible active ingredients and hypopigmentation mechanisms of fermented broth are discussed, and potential applications of fermented broth in the cosmetic industry are also addressed.

  12. Energy efficiency through energy audit

    International Nuclear Information System (INIS)

    Esan, A. A.

    2000-08-01

    Energy is an essential factor to economic and social development and improved standards of living in developing countries. Nigeria in particular. There is a strong need for greater energy efficiency in every sector of economy in order to reduce costs. enhance competitiveness, conserve energy resources and reduce environmental impacts associated with production, distribution and use of energy. Energy auditing and monitoring has a significant role in any energy management and conservation project. Energy auditing as an important part of industrial energy management on plant level, represents a complex of activities aiming at the efficient use of energy. The activities are undertaken by a team of experts who use a set of measuring instruments to monitor and evaluate all the necessary data to elaborate a package of recommendations on improvements in the field of energy efficiency and possible product quality. The inefficient conversion and use of energy have been identified as a central problem for all developing countries, Nigeria inclusive, since they all consume significantly higher amounts of energy per unit of GDP than OECD countries. This aggravates energy-related environmental problems and is also a burden on domestic resources and foreign exchange. Energy prices have risen drastically in many developing countries, while energy intensities remain high. Price changes alone are not rapidly translating energy efficiency improvements. Identifying and removing the obstacles to greater energy efficiency should be priority for government in developing countries. This is why the Energy Commission, an apex organ of government on Energy matters in all its ramifications is out to encourage relatively low-cost energy audits for the Textile industries - such audits can identify ''good house-keeping's' measures, such as simply process improvements, that reduce energy consumption and operating costs. This will be followed by the training of plant workers/energy managers

  13. Inhibition of ice recrystallization and cryoprotective activity of wheat proteins in liver and pancreatic cells.

    Science.gov (United States)

    Chow-Shi-Yée, Mélanie; Briard, Jennie G; Grondin, Mélanie; Averill-Bates, Diana A; Ben, Robert N; Ouellet, François

    2016-05-01

    Efficient cryopreservation of cells at ultralow temperatures requires the use of substances that help maintain viability and metabolic functions post-thaw. We are developing new technology where plant proteins are used to substitute the commonly-used, but relatively toxic chemical dimethyl sulfoxide. Recombinant forms of four structurally diverse wheat proteins, TaIRI-2 (ice recrystallization inhibition), TaBAS1 (2-Cys peroxiredoxin), WCS120 (dehydrin), and TaENO (enolase) can efficiently cryopreserve hepatocytes and insulin-secreting INS832/13 cells. This study shows that TaIRI-2 and TaENO are internalized during the freeze-thaw process, while TaBAS1 and WCS120 remain at the extracellular level. Possible antifreeze activity of the four proteins was assessed. The "splat cooling" method for quantifying ice recrystallization inhibition activity (a property that characterizes antifreeze proteins) revealed that TaIRI-2 and TaENO are more potent than TaBAS1 and WCS120. Because of their ability to inhibit ice recrystallization, the wheat recombinant proteins TaIRI-2 and TaENO are promising candidates and could prove useful to improve cryopreservation protocols for hepatocytes and insulin-secreting cells, and possibly other cell types. TaENO does not have typical ice-binding domains, and the TargetFreeze tool did not predict an antifreeze capacity, suggesting the existence of nontypical antifreeze domains. The fact that TaBAS1 is an efficient cryoprotectant but does not show antifreeze activity indicates a different mechanism of action. The cryoprotective properties conferred by WCS120 depend on biochemical properties that remain to be determined. Overall, our results show that the proteins' efficiencies vary between cell types, and confirm that a combination of different protection mechanisms is needed to successfully cryopreserve mammalian cells. © 2016 The Protein Society.

  14. Tiotropium bromide inhibits human monocyte chemotaxis

    Directory of Open Access Journals (Sweden)

    Kurai M

    2012-08-01

    Full Text Available Tiotropium bromide (Spiriva® is used as a bronchodilator in chronic obstructive pulmonary disease (COPD. However, clinical evidence suggests that tiotropium bromide may improve COPD by mechanisms beyond bronchodilation. We hypothesized that tiotropium bromide may act as an anti-inflammatory agent by inhibiting monocyte chemotaxis, a process that plays an important role in the lung inflammation of COPD. To test this hypothesis monocytes were pretreated with tiotropium bromide prior to exposure to chemotactic agents and monocyte chemotactic activity (MCA was evaluated with a blind chamber technique. Tiotropium bromide inhibited MCA in a dose- and time- dependent manner (respectively, p< 0.01 by directly acting on the monocyte. Acetylcholine (ACh challenge increased MCA (p< 0.01, and tiotropium bromide effectively reduced (p< 0.01 the increase in MCA by ACh. The inhibition of MCA by tiotropium bromide was reversed by a muscarinic type 3 (M3-muscarinic receptor antagonist (p< 0.01, and was not effected by an M2 receptor antagonist. Furthermore, a selective M3 receptor agonist, cevimeline, and Gq protein stimulator, Pasteurella multocida toxin, significantly increased MCA (P < 0.01, and tiotropium bromide pretreatment reduced (p< 0.01 the increase in MCA induced by these agents. These results suggest that tiotropium might regulate monocyte chemotaxis, in part, by interfering with M3-muscarinic receptor coupled Gq protein signal transduction. These results provide new insight that an anti-cholinergic therapeutic may provide anti-inflammatory action in the pulmonary system.

  15. Menaquinone analogs inhibit growth of bacterial pathogens.

    Science.gov (United States)

    Schlievert, Patrick M; Merriman, Joseph A; Salgado-Pabón, Wilmara; Mueller, Elizabeth A; Spaulding, Adam R; Vu, Bao G; Chuang-Smith, Olivia N; Kohler, Petra L; Kirby, John R

    2013-11-01

    Gram-positive bacteria cause serious human illnesses through combinations of cell surface and secreted virulence factors. We initiated studies with four of these organisms to develop novel topical antibacterial agents that interfere with growth and exotoxin production, focusing on menaquinone analogs. Menadione, 1,4-naphthoquinone, and coenzymes Q1 to Q3 but not menaquinone, phylloquinone, or coenzyme Q10 inhibited the growth and to a greater extent exotoxin production of Staphylococcus aureus, Bacillus anthracis, Streptococcus pyogenes, and Streptococcus agalactiae at concentrations of 10 to 200 μg/ml. Coenzyme Q1 reduced the ability of S. aureus to cause toxic shock syndrome in a rabbit model, inhibited the growth of four Gram-negative bacteria, and synergized with another antimicrobial agent, glycerol monolaurate, to inhibit S. aureus growth. The staphylococcal two-component system SrrA/B was shown to be an antibacterial target of coenzyme Q1. We hypothesize that menaquinone analogs both induce toxic reactive oxygen species and affect bacterial plasma membranes and biosynthetic machinery to interfere with two-component systems, respiration, and macromolecular synthesis. These compounds represent a novel class of potential topical therapeutic agents.

  16. Exploiting oleuropein for inhibiting collagen fibril formation.

    Science.gov (United States)

    Bharathy, H; Fathima, N Nishad

    2017-08-01

    Collagen fibrils accumulate in excessive amounts and impair the normal functioning of the organ; therefore it stimulates the interest for identifying the compounds that could prevent the formation of fibrils. Herein, inhibition of self-assembly of collagen using oleuropein has been studied. The changes in the physico-chemical characteristics of collagen on interaction with increasing concentration of oleuropein has been studied using techniques like viscosity, UV-vis, CD and FT-IR. The inhibitory effect of oleuropein on fibril formation of collagen was proved using SEM. Circular dichroism and FT-IR spectra elucidates the alterations in the secondary structure of collagen suggesting non-covalent interactions between oleuropein and collagen. The decreased rate of collagen fibril formation also confirms the inhibition in the self-assembly of collagen. Hence, our study suggests that inhibition of the self-assembly process using oleuropein may unfold new avenues to treat fibrotic diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Alpha-amylase inhibition kinetics by caulerpenyne

    Directory of Open Access Journals (Sweden)

    S. CENGIZ

    2010-03-01

    Full Text Available Many algae have important secretions which are generally used for defensive purposes. These secretions take attentions of a lot of researchers who are wondering if these metabolites can be used for medical researches or not. Among these metabolites, caulerpenyne (CYN which is the main metabolite of Caulerpa species, have had an important place in Caulerpa researches since the results related to its determined properties such as cytotoxic, antiviral, antiproliferative and apoptotic effects have been proven by many scientific reports. In the present study, the inhibitory effect of CYN isolated from C. prolifera on alpha-amylase was investigated. The inhibition experiments were done with CYN by spectrophotometric determination method. In order to evaluate the type of inhibition Lineweaver–Burk plot was produced. The results obtained from enzyme kinetic studies exhibited an un-competitive type of inhibition, which is characterized by the difference of Vmax and KM from those of the free enzyme, of alpha-amylase in the presence of CYN. The present study showed that Caulerpa species can be a potential target for producing diabetic drugs in the light of the results obtained for CYN.

  18. Response inhibition in motor conversion disorder.

    Science.gov (United States)

    Voon, Valerie; Ekanayake, Vindhya; Wiggs, Edythe; Kranick, Sarah; Ameli, Rezvan; Harrison, Neil A; Hallett, Mark

    2013-05-01

    Conversion disorders (CDs) are unexplained neurological symptoms presumed to be related to a psychological issue. Studies focusing on conversion paralysis have suggested potential impairments in motor initiation or execution. Here we studied CD patients with aberrant or excessive motor movements and focused on motor response inhibition. We also assessed cognitive measures in multiple domains. We compared 30 CD patients and 30 age-, sex-, and education-matched healthy volunteers on a motor response inhibition task (go/no go), along with verbal motor response inhibition (color-word interference) and measures of attention, sustained attention, processing speed, language, memory, visuospatial processing, and executive function including planning and verbal fluency. CD patients had greater impairments in commission errors on the go/no go task (P conversion. Patients with nonepileptic seizures, a different form of conversion disorder, are commonly reported to have lower IQ and multiple cognitive deficits. Our results point toward potential differences between conversion disorder subgroups. © 2013 Movement Disorder Society. Copyright © 2013 Movement Disorder Society.

  19. Inhibition of Enveloped Viruses Infectivity by Curcumin

    Science.gov (United States)

    Wen, Hsiao-Wei; Ou, Jun-Lin; Chiou, Shyan-Song; Chen, Jo-Mei; Wong, Min-Liang; Hsu, Wei-Li

    2013-01-01

    Curcumin, a natural compound and ingredient in curry, has antiinflammatory, antioxidant, and anticarcinogenic properties. Previously, we reported that curcumin abrogated influenza virus infectivity by inhibiting hemagglutination (HA) activity. This study demonstrates a novel mechanism by which curcumin inhibits the infectivity of enveloped viruses. In all analyzed enveloped viruses, including the influenza virus, curcumin inhibited plaque formation. In contrast, the nonenveloped enterovirus 71 remained unaffected by curcumin treatment. We evaluated the effects of curcumin on the membrane structure using fluorescent dye (sulforhodamine B; SRB)-containing liposomes that mimic the viral envelope. Curcumin treatment induced the leakage of SRB from these liposomes and the addition of the influenza virus reduced the leakage, indicating that curcumin disrupts the integrity of the membranes of viral envelopes and of liposomes. When testing liposomes of various diameters, we detected higher levels of SRB leakage from the smaller-sized liposomes than from the larger liposomes. Interestingly, the curcumin concentration required to reduce plaque formation was lower for the influenza virus (approximately 100 nm in diameter) than for the pseudorabies virus (approximately 180 nm) and the vaccinia virus (roughly 335 × 200 × 200 nm). These data provide insights on the molecular antiviral mechanisms of curcumin and its potential use as an antiviral agent for enveloped viruses. PMID:23658730

  20. Somatomedins inhibit protein degradation in muscle cell

    International Nuclear Information System (INIS)

    Roeder, R.A.; Blann, D.L.; Bauer, C.A.; Hossner, K.L.

    1986-01-01

    Protein degradation has been measured in cultures of L6 myotubes as the rate of release of trichloroacetic acid-soluble radioactivity after prelabeling cell protein with [ 3 H] leucine. Insulin-like growth factor-I (IGF-1), ovine somatomedin (oSM) and insulin (I), at concentrations from 10 -11 M to 10 -7 M (5 x 10 -7 M-oSM) were added at the beginning of a 4-hour degradation period to determine the effects of these hormones on inducible proteolysis occurring in serum-free media. In addition the effects of fetal bovine serum, at concentrations from 1% to 30%, on protein degradation were determined in parallel experiments to relate serum inhibition of proteolysis to somatomedin actions. Results from this study indicate the apparent half maximal inhibition of proteolysis (18%, 15%, 11%) occurred at .4nM-IGF-1, .6nM-oSM and 4nM-I, respectively. Thus protein degradation was approximately 10 times more sensitive to somatomedins than insulin. The half maximal inhibition of proteolysis (15%) observed with serum occurred at 7.7%. The magnitude of the response between IFG-I and serum (37% vs. 31%) was similar. These results are consistent with the hypothesis that somatomedins are important factors in regulating growth and development of muscle

  1. Kinetics, mechanism, and inhibition of monoamine oxidase.

    Science.gov (United States)

    Ramsay, Rona R; Albreht, Alen

    2018-03-07

    Monoamine oxidases (MAOs) catalyse the oxidation of neurotransmitter amines and a wide variety of primary, secondary and tertiary amine xenobiotics, including therapeutic drugs. While inhibition of MAO activity in the periphery removes protection from biogenic amines and so is undesirable, inhibition in the brain gives vital antidepressant and behavioural advantages that make MAO a major pharmaceutical target for inhibitor design. In neurodegenerative diseases, MAO inhibitors can help to maintain neurotransmitter levels, making it a common feature in novel multi-target combinations designed to combat Alzheimer's disease, albeit not yet proven clinically. Vital information for inhibitor design comes from an understanding of the structure, mechanism, and kinetics of the catalyst. This review will summarize the kinetic behaviour of MAO A and B and the kinetic evaluation of reversible inhibitors that transiently decrease catalysis. Kinetic parameters and crystal structures have enabled computational approaches to ligand discovery and validation of hits by docking. Kinetics and a wide variety of substrates and inhibitors along with theoretical modelling have also contributed to proposed schemes for the still debated chemical mechanism of amine oxidation. However, most of the marketed MAO drugs are long-lasting irreversible inactivators. The mechanism of irreversible inhibition by hydrazine, cyclopropylamine, and propargylamine drugs will be discussed. The article finishes with some examples of the propargylamine moiety in multi-target ligand design to combat neurodegeneration.

  2. Inhibition of topoisomerase II by liriodenine.

    Science.gov (United States)

    Woo, S H; Reynolds, M C; Sun, N J; Cassady, J M; Snapka, R M

    1997-08-15

    The cytotoxic oxoaporphine alkaloid liriodenine, isolated from Cananga odorata, was found to be a potent inhibitor of topoisomerase II (EC 5.99.1.3) both in vivo and in vitro. Liriodenine treatment of SV40 (simian virus 40)-infected CV-1 cells caused highly catenated SV40 daughter chromosomes, a signature of topoisomerase II inhibition. Strong catalytic inhibition of topoisomerase II by liriodenine was confirmed by in vitro assays with purified human topoisomerase II and kinetoplast DNA. Liriodenine also caused low-level protein-DNA cross-links to pulse-labeled SV40 chromosomes in vivo, suggesting that it may be a weak topoisomerase II poison. This was supported by the finding that liriodenine caused topoisomerase II-DNA cross-links in an in vitro assay for topoisomerase II poisons. Verapamil did not increase either liriodenine-induced protein-DNA cross-links or catalytic inhibition of topoisomerase II in SV40-infected cells. This indicates that liriodenine is not a substrate for the verapamil-sensitive drug efflux pump in CV-1 cells.

  3. Phytic Acid Inhibits Lipid Peroxidation In Vitro

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    Alicja Zajdel

    2013-01-01

    Full Text Available Phytic acid (PA has been recognized as a potent antioxidant and inhibitor of iron-catalyzed hydroxyl radical formation under in vitro and in vivo conditions. Therefore, the aim of the present study was to investigate, with the use of HPLC/MS/MS, whether PA is capable of inhibiting linoleic acid autoxidation and Fe(II/ascorbate-induced peroxidation, as well as Fe(II/ascorbate-induced lipid peroxidation in human colonic epithelial cells. PA at 100 μM and 500 μM effectively inhibited the decay of linoleic acid, both in the absence and presence of Fe(II/ascorbate. The observed inhibitory effect of PA on Fe(II/ascorbate-induced lipid peroxidation was lower (10–20% compared to that of autoxidation. PA did not change linoleic acid hydroperoxides concentration levels after 24 hours of Fe(II/ascorbate-induced peroxidation. In the absence of Fe(II/ascorbate, PA at 100 μM and 500 μM significantly suppressed decomposition of linoleic acid hydroperoxides. Moreover, PA at the tested nontoxic concentrations (100 μM and 500 μM significantly decreased 4-hydroxyalkenal levels in Caco-2 cells which structurally and functionally resemble the small intestinal epithelium. It is concluded that PA inhibits linoleic acid oxidation and reduces the formation of 4-hydroxyalkenals. Acting as an antioxidant it may help to prevent intestinal diseases induced by oxygen radicals and lipid peroxidation products.

  4. Inhibition of SIRT2 suppresses hepatic fibrosis.

    Science.gov (United States)

    Arteaga, Maribel; Shang, Na; Ding, Xianzhong; Yong, Sherri; Cotler, Scott J; Denning, Mitchell F; Shimamura, Takashi; Breslin, Peter; Lüscher, Bernhard; Qiu, Wei

    2016-06-01

    Liver fibrosis can progress to cirrhosis and result in serious complications of liver disease. The pathogenesis of liver fibrosis involves the activation of hepatic stellate cells (HSCs), the underlying mechanisms of which are not fully known. Emerging evidence suggests that the classic histone deacetylases play a role in liver fibrosis, but the role of another subfamily of histone deacetylases, the sirtuins, in the development of hepatic fibrosis remains unknown. In this study, we found that blocking the activity of sirtuin 2 (SIRT2) by using inhibitors or shRNAs significantly suppressed fibrogenic gene expression in HSCs. We further demonstrated that inhibition of SIRT2 results in the degradation of c-MYC, which is important for HSC activation. In addition, we discovered that inhibition of SIRT2 suppresses the phosphorylation of ERK, which is critical for the stabilization of c-MYC. Moreover, we found that Sirt2 deficiency attenuates the hepatic fibrosis induced by carbon tetrachloride (CCl4) and thioacetamide (TAA). Furthermore, we showed that SIRT2, p-ERK, and c-MYC proteins are all overexpressed in human hepatic fibrotic tissues. These data suggest a critical role for the SIRT2/ERK/c-MYC axis in promoting hepatic fibrogenesis. Inhibition of the SIRT2/ERK/c-MYC axis represents a novel strategy to prevent and to potentially treat liver fibrosis and cirrhosis. Copyright © 2016 the American Physiological Society.

  5. Pharmacological inhibition of feline immunodeficiency virus (FIV).

    Science.gov (United States)

    Mohammadi, Hakimeh; Bienzle, Dorothee

    2012-05-01

    Feline immunodeficiency virus (FIV) is a member of the retroviridae family of viruses and causes an acquired immunodeficiency syndrome (AIDS) in domestic and non-domestic cats worldwide. Genome organization of FIV and clinical characteristics of the disease caused by the virus are similar to those of human immunodeficiency virus (HIV). Both viruses infect T lymphocytes, monocytes and macrophages, and their replication cycle in infected cells is analogous. Due to marked similarity in genomic organization, virus structure, virus replication and disease pathogenesis of FIV and HIV, infection of cats with FIV is a useful tool to study and develop novel drugs and vaccines for HIV. Anti-retroviral drugs studied extensively in HIV infection have targeted different steps of the virus replication cycle: (1) inhibition of virus entry into susceptible cells at the level of attachment to host cell surface receptors and co-receptors; (2) inhibition of fusion of the virus membrane with the cell membrane; (3) blockade of reverse transcription of viral genomic RNA; (4) interruption of nuclear translocation and viral DNA integration into host genomes; (5) prevention of viral transcript processing and nuclear export; and (6) inhibition of virion assembly and maturation. Despite much success of anti-retroviral therapy slowing disease progression in people, similar therapy has not been thoroughly investigated in cats. In this article we review current pharmacological approaches and novel targets for anti-lentiviral therapy, and critically assess potentially suitable applications against FIV infection in cats.

  6. Wnt signaling inhibits CTL memory programming.

    Science.gov (United States)

    Xiao, Zhengguo; Sun, Zhifeng; Smyth, Kendra; Li, Lei

    2013-12-01

    Induction of functional CTLs is one of the major goals for vaccine development and cancer therapy. Inflammatory cytokines are critical for memory CTL generation. Wnt signaling is important for CTL priming and memory formation, but its role in cytokine-driven memory CTL programming is unclear. We found that wnt signaling inhibited IL-12-driven CTL activation and memory programming. This impaired memory CTL programming was attributed to up-regulation of eomes and down-regulation of T-bet. Wnt signaling suppressed the mTOR pathway during CTL activation, which was different to its effects on other cell types. Interestingly, the impaired memory CTL programming by wnt was partially rescued by mTOR inhibitor rapamycin. In conclusion, we found that crosstalk between wnt and the IL-12 signaling inhibits T-bet and mTOR pathways and impairs memory programming which can be recovered in part by rapamycin. In addition, direct inhibition of wnt signaling during CTL activation does not affect CTL memory programming. Therefore, wnt signaling may serve as a new tool for CTL manipulation in autoimmune diseases and immune therapy for certain cancers. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Spatholobus suberectus inhibits osteoclastogenesis and stimulates chondrogenesis.

    Science.gov (United States)

    Im, Nam-Kyung; Lee, Sung-Gyu; Lee, Dong-Sung; Park, Pil-Hoon; Lee, In-Seon; Jeong, Gil-Saeng

    2014-01-01

    This study was carried out to investigate the effect of Spatholobus suberectus Dunn (SS) on the protection of chondral defect and inhibition of osteoclastogenesis. To examine these effects, we measured the matrix metalloproteinase (MMP) levels in SW1353 chondrosarcoma cells and performed tartrate-resistant acid phosphatase (TRAP) staining in bone marrow macrophage (BMM)-derived osteoclasts. To investigate the anti-osteoarthritis (OA) effects, we assessed TNF-α-induced MMP-1, -3, -9 and tissue inhibitors of matrix metalloproteinase (TIMP) expression levels in SW1353 cells. We observed that SS extract significantly inhibited MMP and TIMP expression in SW1353 cells. Also, SS extract inhibited the receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast differentiation. These results suggest that SS extract may have a potential in the treatment of bone loss and chondral defect by suppressing osteoclast differentiation and decreasing the expression of OA factors. Therefore, clarification of the mechanism of the action of SS extract and its active components is needed.

  8. In Vivo Pharmacodynamic Imaging of Proteasome Inhibition

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    Erin A. Kimbrel

    2009-05-01

    Full Text Available Inhibiting the proteolytic activity of the 26S proteasome has been shown to have selective apoptotic effects on cancer cells and to be clinically efficacious in certain malignancies. There is an unmet medical need for additional proteasome inhibitors, and their development will be facilitated by surrogate markers of proteasome function. Toward this end, ectopic fusion of the destruction domain from ornithine decarboxylase (ODC to reporter proteins is often used for assessing proteasome function. For luciferase-based reporters, we hypothesized that the oxygen-dependent destruction domain (ODD from hypoxia-inducible factor 1α (HIF-1α may provide improved sensitivity over luciferase-ODC, owing to its extremely rapid turnover by the proteasome (HIF-1α has a half-life of less than 5 minutes. In the current study, we show that ODD-luciferase affords a greater dynamic range and faster kinetics than luciferase-ODC in sensing proteasome inhibition in vitro. Importantly, ODD-luciferase also serves as an effective in vivo marker of proteasome function in xenograft tumor models, with inhibition being detected by noninvasive imaging within 3 hours of bortezomib administration. These data establish ODD-luciferase as a surrogate marker of proteasome function that can be used both in vitro and in vivo for the development of novel proteasome inhibitors.

  9. Inhibition of enveloped viruses infectivity by curcumin.

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    Tzu-Yen Chen

    Full Text Available Curcumin, a natural compound and ingredient in curry, has antiinflammatory, antioxidant, and anticarcinogenic properties. Previously, we reported that curcumin abrogated influenza virus infectivity by inhibiting hemagglutination (HA activity. This study demonstrates a novel mechanism by which curcumin inhibits the infectivity of enveloped viruses. In all analyzed enveloped viruses, including the influenza virus, curcumin inhibited plaque formation. In contrast, the nonenveloped enterovirus 71 remained unaffected by curcumin treatment. We evaluated the effects of curcumin on the membrane structure using fluorescent dye (sulforhodamine B; SRB-containing liposomes that mimic the viral envelope. Curcumin treatment induced the leakage of SRB from these liposomes and the addition of the influenza virus reduced the leakage, indicating that curcumin disrupts the integrity of the membranes of viral envelopes and of liposomes. When testing liposomes of various diameters, we detected higher levels of SRB leakage from the smaller-sized liposomes than from the larger liposomes. Interestingly, the curcumin concentration required to reduce plaque formation was lower for the influenza virus (approximately 100 nm in diameter than for the pseudorabies virus (approximately 180 nm and the vaccinia virus (roughly 335 × 200 × 200 nm. These data provide insights on the molecular antiviral mechanisms of curcumin and its potential use as an antiviral agent for enveloped viruses.

  10. New Cinchona Oximes Evaluated as Reactivators of Acetylcholinesterase and Butyrylcholinesterase Inhibited by Organophosphorus Compounds

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    Maja Katalinić

    2017-07-01

    Full Text Available For the last six decades, researchers have been focused on finding efficient reactivators of organophosphorus compound (OP-inhibited acetylcholinesterase (AChE and butyrylcholinesterase (BChE. In this study, we have focused our research on a new oxime scaffold based on the Cinchona structure since it was proven to fit the cholinesterases active site and reversibly inhibit their activity. Three Cinchona oximes (C1, C2, and C3, derivatives of the 9-oxocinchonidine, were synthesized and investigated in reactivation of various OP-inhibited AChE and BChE. As the results showed, the tested oximes were more efficient in the reactivation of BChE and they reactivated enzyme activity to up to 70% with reactivation rates similar to known pyridinium oximes used as antidotes in medical practice today. Furthermore, the oximes showed selectivity towards binding to the BChE active site and the determined enzyme-oxime dissociation constants supported work on the future development of inhibitors in other targeted studies (e.g., in treatment of neurodegenerative disease. Also, we monitored the cytotoxic effect of Cinchona oximes on two cell lines Hep G2 and SH-SY5Y to determine the possible limits for in vivo application. The cytotoxicity results support future studies of these compounds as long as their biological activity is targeted in the lower micromolar range.

  11. Opposite responses of rabbit and human globin mRNAs to translational inhibition by cap analogues

    International Nuclear Information System (INIS)

    Shakin, S.H.; Liebhaber, S.A.

    1987-01-01

    The translational efficiency of an mRNA may be determined at the step of translational initiation by the efficiency of its interaction with the cap binding protein complex. To further investigate the role of these interactions in translational control, the authors compare in vitro the relative sensitivities of rabbit and human α- and β-globin mRNAs to translational inhibition by cap analogues. They find that rabbit β-globin mRNA is more resistant to translational inhibition by cap analogues than rabbit α-globin mRNA, while in contrast, human β-globin mRNA is more sensitive to cap analogue inhibition than human α- and β-globin mRNAs is unexpected as direct in vivo and in vitro comparisons of polysome profiles reveal parallel translational handling of the α- and β-globin mRNAs from these two species. This discordance between the relative translational sensitivities of these mRNAs to cap analogues and their relative ribosome loading activities suggests that cap-dependent events may not be rate limiting in steady-state globin translation

  12. Metal inhibition on the reactivity of manganese dioxide toward organic contaminant oxidation in relation to metal adsorption and ionic potential.

    Science.gov (United States)

    Jiang, Jing; Wang, Zhuopu; Chen, Yang; He, Anfei; Li, Jianliang; Sheng, G Daniel

    2017-03-01

    Coexisting metal ions may significantly inhibit the oxidative reactivity of manganese oxides toward organic contaminants in metal-organic multi-pollutant waters. While the metal inhibition on the oxidation of organic contaminants by manganese oxides has previously been reported, the extent of the inhibition in relation to metal properties has not been established. Six alkali, alkaline, and transition metals, as well as two testing metals were evaluated for their abilities to inhibit the reactivity of birnessite. Regardless of the pathways of phenol and diuron oxidation (polymerization vs. breakdown), the extent of metal inhibition depended mainly on the metal itself and its concentration. The observed metal inhibition efficiency followed the order of Mn 2+  > Co 2+  > Cu 2+  > Al 3+  > Mg 2+  > K + , consistent with metal adsorption on birnessite. The first-order organic oxidation rate constant (k obs ) was linearly negatively correlated with metal adsorption (q e ) on birnessite. These observations demonstrated that the metal inhibition efficiency was determined by metal adsorption on birnessite. The slopes of the k obs -q e varied among metals and followed the order of K +  > Ca 2+  > Mg 2+  > Mn 2+  > Cd 2+  > Co 2+  > Cu 2+  > Al 3+ . These slopes defined intrinsic inhibitory abilities of metals. As metals were adsorbed hydrated on birnessite, the intrinsic inhibitory ability was significantly linearly correlated with ionic potentials of metals, leading to a single straight line. Metals with multiple d electrons in the outermost orbit with polarizing energy that promotes hydrolysis sat slightly below the line, and vice versa. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. An Ecofriendly Initiative for the Corrosion Inhibition of Mild Steel in 1 M HCl Using Tecoma capensis Flower Extract

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    A. Prithiba

    2016-01-01

    Full Text Available Corrosion inhibition of mild steel in 1 M HCl in the presence of Tecoma capensis flower extract was carried out by means of mass loss, potentiodynamic polarisation, and electrochemical impedance techniques. The inhibition efficiency varied with concentration of the inhibitor, immersion time, and temperature. The adsorption of the inhibitor on mild steel surface obeys Langmuir’s adsorption isotherm. Thermodynamic parameters reveal that the adsorption process is spontaneous. Electrochemical studies reflect that the inhibitor acts as a mixed-type inhibitor. Surface analytical techniques ascertain the inhibitive nature of the studied inhibitor.

  14. Study of Temperature Effect on the Corrosion Inhibition of C38 Carbon Steel Using Amino-tris(Methylenephosphonic Acid in Hydrochloric Acid Solution

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    Najoua Labjar

    2011-01-01

    Full Text Available Tafel polarization method was used to assess the corrosion inhibitive and adsorption behaviours of amino-tris(methylenephosphonic acid (ATMP for C38 carbon steel in 1 M HCl solution in the temperature range from 30 to 60∘C. It was shown that the corrosion inhibition efficiency was found to increase with increase in ATMP concentration but decreased with temperature, which is suggestive of physical adsorption mechanism. The adsorption of the ATMP onto the C38 steel surface was found to follow Langmuir adsorption isotherm model. The corrosion inhibition mechanism was further corroborated by the values of kinetic and thermodynamic parameters obtained from the experimental data.

  15. Preparation of highly efficient manganese catalase mimics.

    Science.gov (United States)

    Triller, Michael U; Hsieh, Wen-Yuan; Pecoraro, Vincent L; Rompel, Annette; Krebs, Bernt

    2002-10-21

    The series of compounds [Mn(bpia)(mu-OAc)](2)(ClO(4))(2) (1), [Mn(2)(bpia)(2)(muO)(mu-OAc)](ClO(4))(3).CH(3)CN (2), [Mn(bpia)(mu-O)](2)(ClO(4))(2)(PF(6)).2CH(3)CN (3), [Mn(bpia)(Cl)(2)](ClO)(4) (4), and [(Mn(bpia)(Cl))(2)(mu-O)](ClO(4))(2).2CH(3)CN (5) (bpia = bis(picolyl)(N-methylimidazol-2-yl)amine) represents a structural, spectroscopic, and functional model system for manganese catalases. Compounds 3 and 5 have been synthesized from 2 via bulk electrolysis and ligand exchange, respectively. All complexes have been structurally characterized by X-ray crystallography and by UV-vis and EPR spectroscopies. The different bridging ligands including the rare mono-mu-oxo and mono-mu-oxo-mono-mu-carboxylato motifs lead to a variation of the Mn-Mn separation across the four binuclear compounds of 1.50 A (Mn(2)(II,II) = 4.128 A, Mn(2)(III,III) = 3.5326 and 3.2533 A, Mn(2)(III,IV) = 2.624 A). Complexes 1, 2, and 3 are mimics for the Mn(2)(II,II), the Mn(2)(III,III), and the Mn(2)(III,IV) oxidation states of the native enzyme. UV-vis spectra of these compounds show similarities to those of the corresponding oxidation states of manganese catalase from Thermus thermophilus and Lactobacillus plantarum. Compound 2 exhibits a rare example of a Jahn-Teller compression. While complexes 1 and 3 are efficient catalysts for the disproportionation of hydrogen peroxide and contain an N(4)O(2) donor set, 4 and 5 show no catalase activity. These complexes have an N(4)Cl(2) and N(4)OCl donor set, respectively, and serve as mimics for halide inhibited manganese catalases. Cyclovoltammetric data show that the substitution of oxygen donor atoms with chloride causes a shift of redox potentials to more positive values. To our knowledge, complex 1 is the most efficient binuclear functional manganese catalase mimic exhibiting saturation kinetics to date.

  16. Bioassays for the determination of nitrification inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Grunditz, Camilla

    1999-07-01

    Requirements for nitrogen reduction in wastewater treatment plants were introduced in Sweden in the early 1990's. This was a governmental move to reduce the nitrogen discharges to the Baltic and Kattegat in order to prevent eutrophication. The nitrification process in wastewater treatment plants is performed by nitrifying bacteria. These are susceptible to inhibition and it is of great importance that the influent water does not contain toxic compounds. Therefore, there is a need for assays for the determination of nitrification inhibition. This thesis describes the development and applications of such bioassays. Pure cultures of Nitrosomonas sp. and Nitrobacter sp. were isolated from activated sludge of a wastewater treatment plant. These cultures were used as test organisms in the development of bioassays for nitrification inhibition measurements. The assays are based on two different principles; cell suspensions of the bacteria, performed in test tubes, and mediated amperometric biosensors with the bacteria immobilised. Ammonia oxidation and nitrite oxidation are studied separately without interference from other organisms, which makes it easier to interpret the results. The cell suspension assays were applied to samples of industrial and municipal wastewater. The Nitrosomonas and Nitrobacter assays showed to have different inhibition patterns. A large percentage of the Swedish municipal wastewater treatment plants were found to receive inhibitory influent water, but the inhibition level was generally low. Compared to an assay based on activated sludge, the screening method, the pure culture assays found more samples of influent water strongly inhibitory or stimulating. The highest correlation was found between the screening method and the Nitrosomonas assay. The Nitrobacter assay was found to be the most sensitive method. Assessment of toxicity of a number of chemical substances was studied using the biosensors, together with the cell suspension assays

  17. Thiomers: Inhibition of cytochrome P450 activity.

    Science.gov (United States)

    Iqbal, Javed; Sakloetsakun, Duangkamon; Bernkop-Schnürch, Andreas

    2011-08-01

    The aim of the present study was to investigate the potential of different thiolated polymers (thiomers) on the catalytic activity of CYP450s on one hand and to explore new inhibitors for CYP activity on the other hand. Several thiolated polymers including poly(acrylic acid)-cysteine (PAA-cysteine), chitosan-thioglycolic acid (chitosan-TGA), and thiolated PEG-g-PEI copolymer along with brij 35, myrj 52 and the well-established CYPP450 inhibitor verapamil were screened for their CYP3A4 and CYP2A6 inhibitory activity, and their IC(50) values were determined. Both enzyme inhibition assays were performed in 96-well microtiter plates. 7-Benzyloxy-4-(trifluoromethyl)-coumarin (BFC) and 7-hydroxycoumarin (7-HC) were used as fluorescent substrates in order to determine CYP3A4 and CYP2A6 catalytic activity, respectively. All investigated compounds inhibited CYP3A4 as well as CYP2A6 activity. All tested (thiolated) polymers were found to be more potent inhibitors of CYP3A4 than of CYP2A6 catalytic activity. Apart from verapamil that is a known CYP3A4 inhibitor, brij 35 and myrj 52 were explored as potent inhibitors of CYP3A4 and CYP2A6 catalytic activity. Among the tested polymers, the rank order for CYP3A4 inhibition was PAA-cysteine (100 kDa)>brij 35>thiolated PEG-g-PEI copolymer (16 kDa)>myrj 52>PAA (100 kDa)>PAA-cysteine (450 kDa)>verapamil>PAA (450 kDa)>chitosan-TGA (150 kDa)>chitosan (150 kDa). On the other hand, the rank order of CYP2A6 inhibition was brij 35>PAA-cysteine (100kDa)>chitosan-TGA (150 kDa)>PAA (100 kDa)>thiolated PEG-g-PEI copolymer (16 kDa)>PAA-cysteine (450 kDa)>chitosan (150 kDa)>verapamil>PAA (450 kDa)>myrj 52. Thus, this study suggests that (thiolated) polymers display a promising potential to inhibit cytochrome P450s activity and might turn out to be potentially valuable tools for improving the oral bioavailability of actively secreted compounds by avoiding intestinal metabolism. Copyright © 2011. Published by Elsevier B.V.

  18. The antimicrobial efficiency of silver activated sorbents

    Science.gov (United States)

    Đolić, Maja B.; Rajaković-Ognjanović, Vladana N.; Štrbac, Svetlana B.; Rakočević, Zlatko Lj.; Veljović, Đorđe N.; Dimitrijević, Suzana I.; Rajaković, Ljubinka V.

    2015-12-01

    This study is focused on the surface modifications of the materials that are used for antimicrobial water treatment. Sorbents of different origin were activated by Ag+-ions. The selection of the most appropriate materials and the most effective activation agents was done according to the results of the sorption and desorption kinetic studies. Sorption capacities of selected sorbents: granulated activated carbon (GAC), zeolite (Z), and titanium dioxide (T), activated by Ag+-ions were following: 42.06, 13.51 and 17.53 mg/g, respectively. The antimicrobial activity of Ag/Z, Ag/GAC and Ag/T sorbents were tested against Gram-negative bacteria E. coli, Gram-positive bacteria S. aureus and yeast C. albicans. After 15 min of exposure period, the highest cell removal was obtained using Ag/Z against S. aureus and E. coli, 98.8 and 93.5%, respectively. Yeast cell inactivation was unsatisfactory for all three activated sorbents. The antimicrobial pathway of the activated sorbents has been examined by two separate tests - Ag+-ions desorbed from the activated surface to the aqueous phase and microbial cell removal caused by the Ag+-ions from the solid phase (activated surface sites). The results indicated that disinfection process significantly depended on the microbial-activated sites interactions on the modified surface. The chemical state of the activating agent had crucial impact to the inhibition rate. The characterization of the native and modified sorbents was performed by X-ray diffraction technique, X-ray photoelectron spectroscopy and scanning electron microscope. The concentration of adsorbed and released ions was determined by inductively coupled plasma optical emission spectroscopy and mass spectrometry. The antimicrobial efficiency of activated sorbents was related not only to the concentration of the activating agent, but moreover on the surface characteristics of the material, which affects the distribution and the accessibility of the activating agent.

  19. Contribution of hydrogen peroxide to the inhibition of Staphylococcus aureus by Lactococcus garvieae in interaction with raw milk microbial community

    OpenAIRE

    Delbes, Céline; Dorchies, Géraud; Chaabna, Zineddine; Callon, Cecile; Montel, Marie-Christine

    2010-01-01

    The response of Staphylococcus aureus growth inhibition by Lactococcus garvieae to catalase and milk lactoperoxidase, and its efficiency in raw milk cheese were evaluated. S. aureus and L. garvieae were co-cultivated in broth buffered at pH 6.8, and in raw, pasteurized and microfiltered milk, in presence and absence of catalase. Although H(2)O(2) production by L garvieae was detected only in agitated broth, the inhibition of S. aureus by L garvieae was reduced by catalase both in stati...

  20. Inhibition Effect of Glycerol on the Corrosion of Copper in NaCl Solutions at Different pH Values

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    Santos Lorenzo Chi-Ucán

    2014-01-01

    Full Text Available The inhibitory effect of glycerol on copper corrosion in aerated NaCl (0.5 M solutions at three pH values (4, 7, and 10 was evaluated. Inhibition efficiency was assessed with conventional electrochemical techniques: open circuit potential, potentiodynamic polarization, and electrochemical impedance analysis. Glycerol reduced the corrosion rate of copper in NaCl solutions. The best inhibition effect (η≈83% was produced in alkaline (pH 10 chloride media. This effect can be ascribed to increased viscosity and the presence of copper-glycerol complexes.