- Effects of a mileage tax for trucks
- Luechinger, S., Roth, F. | Journal of urban economics (v.92 / pp.1-15 / 20160094-1190)
- We evaluate the effect of the introduction of a mileage tax for trucks in Switzerland in 2001 on traffic volume and externalities. Using a regression discontinuity design
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We evaluate the effect of the introduction of a mileage tax for trucks in Switzerland in 2001 on traffic volume and externalities. Using a regression discontinuity design, we find a reduction in overall truck traffic of around 4-6%, no effects on car traffic and time-shifted placebos, suggestive evidence for traffic substitution toward rail, and negative effects on nitrogen oxides at curbside monitors. Complementary estimates on the effects of the German mileage tax and complementary estimates based on the synthetic control method are broadly consistent with our main results, although the latter are not statistically significant. Depending on prevailing levels of transportation costs, mileage tax-induced transportation cost increases may accelerate or reverse spatial economic concentration processes. Such implications for economic geography featured prominently in Switzerland and are a promising area for future research.
- The influence of the polar head-group of synthetic cationic lipids on the transfection efficiency mediated by niosomes in rat retina and brain
- Ojeda, E., Puras, G., Agirre, M., Zarate, J., Grijalvo, S., Eritja, R., Martinez-Navarrete, G., Soto-Sanchez, C., Diaz-Tahoces, A., Aviles-Trigueros, M., Fernandez, E., Pedraz, J.L. | Biomaterials (v.77 / pp.267-279 / 20160142-9612)
- The development of novel non-viral delivery vehicles is essential in the search of more efficient strategies for retina and brain diseases. Herein, optimized niosome form
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The development of novel non-viral delivery vehicles is essential in the search of more efficient strategies for retina and brain diseases. Herein, optimized niosome formulations prepared by oil-in water (o/w) and film-hydration techniques were characterized in terms of size, PDI, zeta potential, morphology and stability. Three ionizable glycerol-based cationic lipids containing a primary amine group (lipid 1), a triglycine group (lipid 2) and a dimethylamino ethyl pendent group (lipid 3) as polar head-groups were part of such niosomes. Upon the addition of pCMS-EGFP plasmid, nioplexes were obtained at different cationic lipid/DNA ratios (w/w). The resultant nioplexes were further physicochemically characterized and evaluated to condense, release and protect the DNA against enzymatic digestion. In vitro experiments were performed to evaluate transfection efficiency and cell viability in HEK-293, ARPE-19 and PECC cells. Interestingly, niosome formulations based on lipid 3 showed better transfection efficiencies in ARPE-19 and PECC cells than the rest of cationic lipids showed in this study. In vivo experiments in rat retina after intravitreal and subretinal injections together with in rat brain after cerebral cortex administration showed promising transfection efficiencies when niosome formulations based on lipid 3 were used. These results provide new insights for the development of non-viral vectors based on cationic lipids and their applications for efficient delivery of genetic material to the retina and brain.
- Injection Augmentation for Chronic Cough
- Crawley, B.K., Murry, T., Sulica, L. | Journal of voice : official journal of the Voice Foundation (v.29 / no.6 / pp.763-767 / 20150892-1997)
- Objectives/Hypothesis: Chronic cough (CC) is a pervasive and expensive health problem in the United States. Almost as diverse as its etiologies are the available therapeu
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Objectives/Hypothesis: Chronic cough (CC) is a pervasive and expensive health problem in the United States. Almost as diverse as its etiologies are the available therapeutic options. When vocal fold paresis and CC coincide, injection augmentation may provide an alternative to standard medical and behavioral treatments for CC. Our objective was to assess the effect of injection augmentation in a selected group of patients with CC who had failed multiple medical and behavioral treatments. Study Design: The study design is a retrospective case review. Methods: Our study group included six subjects (1 male and 5 females; aged 24-84 y) who presented for laryngologic evaluation with a chief complaint of CC unresponsive to conventional medical and behavioral management. The cough severity index (CSI), reflux symptom index (RSI), dyspnea severity index (DSI), and voice handicap index-10 (VHI-10), as well as subjective evaluation were assessed before and after the injection augmentation of the vocal folds was undertaken. Results: Five of six patients reported subjective improvement in cough. CSI scores improved in all six (average change 7.3, range 2-13). RSI and DSI scores also improved significantly after injection, whereas VHI-10 scores did not significantly change. One patient reported transient hoarseness after injection that completely resolved. One patient received injection augmentation three times, as the material resorbed and symptoms returned. Conclusions: Injection augmentation effected relief from CC in a select group of patients with CC refractory to previous medical and/or behavioral treatments. This intervention is a novel option for such patients and offers an alternative approach to medical treatment.
- Chloride-Inducible Expression Vector for Delivery of Antimicrobial Peptides Targeting Antibiotic-Resistant Enterococcus faecium
- Geldart, Kathryn, Borrero, Juan, Kaznessis, Yiannis N. | Applied and environmental microbiology (v.81 / no.11 / pp.3889-3897 / 20150099-2240)
- Antibiotic-resistant enterococcal infections are a major concern in hospitals where patients with compromised immunity are readily infected. Enterococcus faecium bacter
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Antibiotic-resistant enterococcal infections are a major concern in hospitals where patients with compromised immunity are readily infected. Enterococcus faecium bacteria are of particular interest as these pathogens account for over 80% of vancomycin-resistant enterococcal infections. Antimicrobial peptides (AMPs) produced at the site of infection by engineered bacteria may offer a potential alternative to traditional antibiotics for the treatment of resistant bacteria such as E. faecium . For this mode of delivery to be effective, it is essential to identify a suitable protein expression system that can be used in the desired delivery bacterium. In this study, we describe a promising chloride-inducible promoter and its application in the bacterial delivery of AMPs from Lactococcus lactis to reduce counts of E. faecium bacteria in vitro . Reporter gene studies show that at chloride concentrations found within the human intestines, the chloride-inducible promoter exhibits high levels of protein expression compared to those of the commonly used nisin-inducible promoter. These results indicate that this system is powerful and would not require the exogenous administration of an inducer molecule. In its application for AMP production against E. faecium in vitro , L. lactis producing AMPs under the chloride promoter rapidly decreased E. faecium counts by nearly 10,000-fold. As an extension of this application, we also demonstrate the potential in using this type of delivery system in combination with traditional antibiotics to slow the development of resistance. Collectively, this study shows the promise of using a chloride-inducible promoter for the bacterial delivery of AMPs in the body for the treatment of vancomycin-resistant enterococci (VRE) and other antibiotic-resistant bacteria.
- Natural products as zinc-dependent histone deacetylase inhibitors.
- Tan, Shuai, Liu, Zhao-Peng | ChemMedChem : Chemistry Enabling Drug Discovery (v.10 / no.3 / pp.441-450 / 20151860-7179)
- Zinc-dependent histone deacetylases (HDACs), a family of hydrolases that remove acetyl groups from lysine residues, play an important role in the regulation of multiple p
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Zinc-dependent histone deacetylases (HDACs), a family of hydrolases that remove acetyl groups from lysine residues, play an important role in the regulation of multiple processes, from gene expression to protein activity. The dysregulation of HDACs is associated with many diseases including cancer, neurological disorders, cellular metabolism disorders, and inflammation. Molecules that act as HDAC inhibitors (HDACi) exhibit a variety of related bioactivities. In particular, HDACi have been applied clinically for the treatment of cancers. Inhibition through competitive binding of the catalytic domain of these enzymes has been achieved by a diverse array of small-molecule chemotypes, including a number of natural products. This review provides a systematic introduction of natural HDACi, with an emphasis on their enzyme inhibitory potency, selectivity, and biological activities, highlighting their various binding modes with HDACs.
- In Situ Generation of Cellulose Nanocrystals in Polycaprolactone Nanofibers: Effects on Crystallinity, Mechanical Strength, Biocompatibility, and Biomimetic Mineralization
- Joshi, Mahesh Kumar, Tiwari, Arjun Prasad, Pant, Hem Raj, Shrestha, Bishnu Kumar, Kim, Han Joo, Park, Chan Hee, Kim, Cheol Sang | ACS applied materials interfaces (v.7 / no.35 / pp.19672-19683 / 20151944-8244)
- Post-electrospinning treatment is a facile process to improve the properties of electrospun nanofibers for various applications. This technique is commonly used when dire
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Post-electrospinning treatment is a facile process to improve the properties of electrospun nanofibers for various applications. This technique is commonly used when direct electrospinning is not a suitable option to fabricate a nonwoven membrane of the desired polymer in a preferred morphology. In this study, a representative natural-synthetic hybrid of cellulose acetate (CA) and polycaprolactone (PCL) in different ratios was fabricated using an electrospinning process, and CA in the hybrid fiber was transformed into cellulose (CL) by post-electrospinning treatment via alkaline saponification. Scanning electron microscopy was employed to study the effects of polymer composition and subsequent saponification on the morphology of the nanofibers. Increasing the PCL content in the PCL/CA blend solution caused a gradual decrease in viscosity, resulting in smoother and more uniform fibers. The saponification of fibers lead to pronounced changes in the physicochemical properties. The crystallinity of the PCL in the composite fiber was varied according to the composition of the component polymers. The water contact angle was considerably decreased (from 124¡Æ to less than 20¡Æ), and the mechanical properties were greatly enhanced (Young rsquo;s Modulus was improved by asymp;20 ndash;30 fold, tensile strength by 3 ndash;4 fold, and tensile stress by asymp;2 ndash;4 fold) compared to those of PCL and PCL/CA membranes. Regeneration of cellulose chains in the nanofibers increased the number of hydroxyl groups, which increased the hydrogen bonding, thereby improving the mechanical properties and wettability of the composite nanofibers. The improved wettability and presence of surface functional groups enhanced the ability to nucleate bioactive calcium phosphate crystals throughout the matrix when exposed to a simulated body fluid solution. Experimental results of cell viability assay, confocal microscopy, and scanning electron microscopy imaging showed that the fabricated nanofibrous membranes have excellent ability for MC3T3-E1 cell proliferation and growth. Given the versatility and widespread use of cellulose ndash;synthetic hybrid systems in the construction of tissue-engineered scaffolds, this work provides a novel strategy to fabricate the biopolymer-based materials for applications in tissue engineering and regenerative medicine. Graphic Abstract ACS Electronic Supporting Info
- Accounting for heritage assets: Does measuring economic value 'kill the cat'?
- Ellwood, S., Greenwood, M. | Critical perspectives on accounting (v.38 / pp.1-13 / 20161045-2354)
- Recent changes in accounting directives for heritage assets held by government, local authorities and charities in the UK required their recognition in the financial stat
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Recent changes in accounting directives for heritage assets held by government, local authorities and charities in the UK required their recognition in the financial statements and the measurement of their economic value. Subsequently, numerous sales of heritage assets by local authorities have occurred. We examine the intrusion of economic value into the realm of cultural assets and investigate two cases: the National Portrait Gallery and Tower Hamlets Council. The observation of economic and cultural value is considered. The National Portrait Gallery largely resisted the pressure to place economic values on its collections of portraiture and continues to increase its extensive collections. The London council in a deprived borough, Tower Hamlets, followed the Code of Practice on local authority accounting regarding recognition and valuation of assets and decided to sell its major heritage asset, a Henry Moore sculpture. We examine how measuring value can affect the observed reality: did the very act of measuring a heritage asset in financial terms change the situation? We develop a frame of analysis based on scientific observation theory applied within the socially constructed world of accounting. Accounting constructed a 'reality' (Hines, 1988) that included items of economic value that were primarily held for their cultural properties, but observing (measuring) their economic value may affect the perception of the cultural value of the item. Drawing on quantum physics we borrow from Schrodinger's thought experiment, commonly referred to as 'Schrodinger's cat', and from Heisenberg's uncertainty principle to suggest that though not killing the cat, observation of the economic value of an accounting element can lead to a change in the perceived cultural value. Thought experiments from quantum physics can provide new ways of exploring the measurement (observation) of different values. Precision in measuring one attribute can cause the perception of other attributes (values) to change. This is particularly important as accounting moves to reporting on an integrated value approach (International Integrated Reporting Council (IIRC), 2013).
- How reliable are self-report measures of mileage, violations and crashes?
- af Wahlberg, A.E., Dorn, L. | Safety science (v.76 / pp.67-73 / 20150925-7535)
- The use of self-reported driver mileage, violations and crashes is very popular in traffic safety research, but their validity has been questioned. One way of testing val
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The use of self-reported driver mileage, violations and crashes is very popular in traffic safety research, but their validity has been questioned. One way of testing validity is with an analysis of test-retest reliability. Three mechanisms might influence reliability in self report; actual changes in the variable over time, stable systematic reporting bias, and random error. Four samples of drivers who had responded twice to an online questionnaire asking them to report their mileage, violations and crashes were used and correlations between self reports for this data were calculated. The results for crashes were compared to expected correlations, calculated from the error introduced by the non-overlapping periods and the variable means. Reliability was fairly low, and controlling for mileage in the violations and crashes calculations did not strengthen the associations. The correlation between self reports of crashes in different time periods was found to be much larger than expected in one case, indicating a report bias, while the other correlation agreed with the predicted value. The correlations for overlapping time periods were much smaller than expected. These results indicate that drivers' self reports about their mileage, violations and crashes are very unreliable, but also that several different mechanisms are operating. It is uncertain exactly under what circumstances different types of self report bias is operating. Traffic safety researchers should treat the use of self-reported mileage, violations and crashes with extreme caution and preferably investigate these variables with the use of objective data.
- Thermodynamics and kinetics of the growth mechanism of vapor-liquid-solid grown nanowires
- Koto, M. | Journal of crystal growth (v.424 / pp.49-54 / 20150022-0248)
- Nanowires are widely regarded as building blocks for next-generation devices because of their unique characteristics, particularly their morphology. The vapor-liquid-soli
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Nanowires are widely regarded as building blocks for next-generation devices because of their unique characteristics, particularly their morphology. The vapor-liquid-solid (VLS) system has attracted much attention as a standard method for obtaining nanowires. Although there are many studies, the VLS mechanism is still not fully understood. We have investigated the thermodynamics and kinetics of the VLS growth mechanism, focusing on the composition of the catalyst and reaction species. We elucidated the definition of the chemical potential of each phase based on the phase diagram and the origin of the phase transition driving force, particularly between the liquid and solid phases. The equilibrium state can be altered by the reaction species composition, the shape factor, nanowire diameter, which changes the chemical potential of the liquid phase. In addition, we show the flow of the particles of the reaction species and the relationship with the chemical potential during steady state growth.
- Chloride-promoted formation of octahedral LiNi0.5Mn1.5O4 crystal with greatly enhanced electrochemical performance
- Feng, F., Liang, C., Fang, H., Yang, B., Ma, W., Dai, Y. | Ceramics international (v.42 / no.7 / pp.9038-9045 / 20160272-8842)
- Two LiNi 0.5 Mn 1.5 O 4 samples are synthesized by a low-temperature solid-state method using chlorides or acetates as raw materials, and their crystal structure, s
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Two LiNi 0.5 Mn 1.5 O 4 samples are synthesized by a low-temperature solid-state method using chlorides or acetates as raw materials, and their crystal structure, size, morphology and electrochemical performance are comparatively investigated. The results show that the two samples have the same crystal structure but with different crystal size and morphology. The LiNi 0.5 Mn 1.5 O 4 prepared from chlorides shows relatively bigger crystals with a well-developed octahedral shape with {111} faces, while the LiNi 0.5 Mn 1.5 O 4 prepared from acetates displays a quasi octahedral shape whose edges and corners are not fully developed. Such a difference in crystal size and morphology leads to a big difference in their electrochemical performance, and the octahedral LiNi 0.5 Mn 1.5 O 4 prepared from chlorides has higher capacity, much better rate capability and cycling performance. Our results suggest that the crystal size and morphology difference of the two samples may be associated with the presence of unreacted chloride in the precursor derived from raw materials of chlorides, and the presence of chloride may effectively promote the formation of octahedral LiNi 0.5 Mn 1.5 O 4 crystal at low temperature via a solid-state reaction (500 o C in this work)
- Organic reactions for the electrochemical and photochemical production of chemical fuels from CO2 - The reduction chemistry of carboxylic acids and derivatives as bent CO2 surrogates
- Luca, O.R., Fenwick, A.Q. | Journal of photochemistry and photobiology. B, Biology (v.152 / no.1 / pp.26-42 / 20151011-1344)
- The present review covers organic transformations involved in the reduction of CO 2 to chemical fuels. In particular, we focus on reactions of CO 2 with organic molec
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The present review covers organic transformations involved in the reduction of CO 2 to chemical fuels. In particular, we focus on reactions of CO 2 with organic molecules to yield carboxylic acid derivatives as a first step in CO 2 reduction reaction sequences. These biomimetic initial steps create opportunities for tandem electrochemical/chemical reductions. We draw parallels between long-standing knowledge of CO 2 reactivity from organic chemistry, organocatalysis, surface science and electrocatalysis. We point out some possible non-faradaic chemical reactions that may contribute to product distributions in the production of solar fuels from CO 2 . These reactions may be accelerated by thermal effects such as resistive heating and illumination.
- Equitable and progressive distance-based user charges design and evaluation of income-based mileage fees in Maryland
- Yang, D., Kastrouni, E., Zhang, L. | Transport policy (v.47 / pp.169-177 / 20160967-070x)
- As a result of the declining purchasing power of fuel tax revenues, the Highway Trust Fund (HTF) is currently insufficient to maintain and expand the U.S. surface transpo
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As a result of the declining purchasing power of fuel tax revenues, the Highway Trust Fund (HTF) is currently insufficient to maintain and expand the U.S. surface transportation system. Alternative revenue sources should be considered to address the insolvency of the current funding system. Mileage fees and value pricing have long been attractive options to researchers and decision-makers, but they often raise concerns of equity. This paper aims to design and evaluate equitable and progressive distance-based user fee policies, focusing specifically on income-based fee rate structures. In addition to equity, the policy design criteria must also include practicality, simplicity, revenue generation, and a consideration of the design's impact on surrounding jurisdictions. Three variable-rate vehicle-miles-traveled (VMT) fee scenarios with respect to income are introduced: Ramsey pricing, fixed-interval incremental, and fixed-percentage incremental structures. All policy scenarios are tested with a statewide transportation model in Maryland. Results show that income-based VMT fees can better protect lower-income households while generating additional revenue; however, a standard fee structure based on Ramsey pricing, or the inverse-elasticity rule, does not work as well as the fixed-interval incremental fee structure. The latter is progressive across all income groups while ensuring that equity and revenue goals are met.
- The archite(x/c)ture of cinematic Milan
- Melnikova, Irina | Journal of European studies (v.45 / no.2 / pp.106-121 / 20150047-2441)
- The paper focuses on the issue of cinematic representation of Milan. The approach is based on Henri Lefebvre #x2019;s well-known argument regarding the importance of the
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The paper focuses on the issue of cinematic representation of Milan. The approach is based on Henri Lefebvre #x2019;s well-known argument regarding the importance of the textual nature of the city per se applicable to the analysis of the cinematic city. The analysis considers the ways in which Italian filmmakers represent Milan. It attempts to outline the #x2018;classical map #x2019; of textual Milan created in Italian cinema and examines its changes in Luca Guadagnino #x2019;s recent film Io sono l #x2019;amore ( I Am Love , 2009). The analysis of the configuration of the diegetic city-space together with the exploration of the narrative devices in the representation of the city in Guadagnino #x2019;s film help to delineate the significance of a new cityscape and evaluate the changes to the #x2018;classical map #x2019; of cinematic Milan.
- Imagination in Vico and Hobbes: From affective sensemaking to culture
- Pern, Tuuli | Culture psychology (v.21 / no.2 / pp.162-184 / 20151354-067x)
- Giambattista Vico and Thomas Hobbes both are known for the particular emphasis they put on the workings of imagination in human understanding. Their respective concepts o
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Giambattista Vico and Thomas Hobbes both are known for the particular emphasis they put on the workings of imagination in human understanding. Their respective concepts of imagination are compared in this article, with attention to the sensory basis and cultural products related to this capability. The connections and contrasts established in the analysis are contextualized by the notion of affective semiosis. An affective component can be traced at the basis of the process of image creation in both authors. The primary level of human semiotic activity where the most basic differentiation and identification processes take place must describe not only in terms of sensation but also affect, imagination, and memory. The expression of these processes on the level of culture is however understood and valued differently by Vico and Hobbes. Vico sees in myth and metaphor the necessary elements of imaginative sensemaking, for Hobbes they take the role of by-products in mind #x2019;s struggle toward rationality.
- Virtuelle 3-D-Laparoskopie-Simulation in der chirurgischen Aus- und Weiterbildung ndash; Ergebnisse einer Pilotstudie
- Kneist, W., Huber, T., Paschold, M., Lang, H. | Zentralblatt f uuml;r Chirurgie (v.141 / no.3 / pp.297-301 / 20160044-409x)
- Background: The use of three-dimensional imaging in laparoscopy is a growing issue and has led to 3D systems in laparoscopic simulation. Studies on box trainers have show
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Background: The use of three-dimensional imaging in laparoscopy is a growing issue and has led to 3D systems in laparoscopic simulation. Studies on box trainers have shown differing results concerning the benefit of 3D imaging. There are currently no studies analysing 3D imaging in virtual reality laparoscopy (VRL). Materials and Methods: Five surgical fellows, 10 surgical residents and 29 undergraduate medical students performed abstract and procedural tasks on a VRL simulator using conventional 2D and 3D imaging in a randomised order. Results: No significant differences between the two imaging systems were shown for students or medical professionals. Participants who preferred three-dimensional imaging showed significantly better results in 2D as wells as in 3D imaging. Discussion: First results on three-dimensional imaging on box trainers showed different results. Some studies resulted in an advantage of 3D imaging for laparoscopic novices. This study did not confirm the superiority of 3D imaging over conventional 2D imaging in a VRL simulator. Conclusion: In the present study on 3D imaging on a VRL simulator there was no significant advantage for 3D imaging compared to conventional 2D imaging.
- Chloride penetration in cracked mortar and the influence of autogenous crack healing
- Maes, M., Snoeck, D., De Belie, N. | Construction building materials (v.115 / pp.114-124 / 20160950-0618)
- Cracks in cementitious materials have a negative influence on the durability in aggressive environments, especially in marine environments since chlorides and sulphates a
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Cracks in cementitious materials have a negative influence on the durability in aggressive environments, especially in marine environments since chlorides and sulphates are able to penetrate faster. Since constructions in marine environments mostly have an important social function with a high economic impact, repair of the cracks is of utmost importance. In this paper, the ability of the material to heal 100 mu;m and 300 mu;m cracks autogenously in marine environments is investigated. To do so, some Ordinary Portland Cement mortar samples and Blast-furnace Slag blended mortar samples were permanently immersed in chloride solutions as well as in combined chloride and sulphate solutions. Another part of the samples were exposed to wet-dry cycles in water and in chloride solutions. Autogenous crack healing was evaluated by means of microscopic measurements. The resistance against chloride penetration was measured by means of colorimetric measurements and chloride profiles. It was shown that cementitious materials, exposed to a simulated marine environment, are able to heal or seal crack widths up to 100 mu;m. Autogenous healing is obtained by ongoing hydration, calcium carbonate precipitation as well as by formation of a layer of magnesium and sulphate reaction products (brucite) at the surface. Furthermore, the resistance against chloride penetration improves due to the healing process. However, the efficiency depends on the initial crack width.
- Soluble expression and enzymatic activity evaluation of protease from reticuloendotheliosis virus
- Hu, F., Zhao, Y., Qi, X., Cui, H., Gao, Y., Gao, H., Liu, C., Wang, Y., Zhang, Y., Li, K., Wang, X., Wang, Y. | Protein expression and purification (v.114 / pp.64-70 / 20151046-5928)
- The protease (PR) encoded by most retroviruses is deeply involved in the lifecycle and infection process of retroviruses by possessing the specificity necessary to correc
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The protease (PR) encoded by most retroviruses is deeply involved in the lifecycle and infection process of retroviruses by possessing the specificity necessary to correctly cleave the viral polyproteins and host cell proteins. However, as an important representative of avian retroviruses, the enzymatic properties of PR from reticuloendotheliosis virus (REV) have not been clearly documented. The recombinant PR, its mutant fused with a His-tag, and its substrate p18-p30 fused with a GST-tag were expressed in the Escherichia coli system as soluble enzymes. The soluble PR and p18-p30 were purified using Ni-NTA His Bind Resin and Glutathione Sepharose 4B, respectively. The enzymatic activity of PR was analyzed using the substrate of p18-p30. The expressed prokaryotic protease has enzyme activity that is dependent on such conditions as temperature, pH, and ions, and its activity can be inhibited by caspase inhibitor and the divalent metal ions Ca 2+ and Ni 2+ . In addition, the key role of the residue Thr (amino acids 28) for the enzymatic activity of PR was identified. Furthermore, the caspase inhibitor Z-VAD-FMK was confirmed to inhibit the PR enzymatic activity of REV. For the first time, the PR of REV was expressed in the soluble form, and the optimal enzymatic reaction system in vitro was developed and preliminarily used. This study provides essential tools and information for further understanding the infection mechanism of REV and for the development of antiviral drugs treating retroviruses.
- Integrating Chemical Information Instruction into the Chemistry Curriculum on Borrowed Time: A Multiyear Case Study of a Capstone Research Report for Organic Chemistry
- Jacobs, Danielle L., Dalal, Heather A., Dawson, Patricia H. | Journal of chemical education (v.93 / no.3 / pp.444-451 / 20160021-9584)
- To develop information literacy skills in chemistry and biochemistry majors at a primarily undergraduate institution, a multiyear collaboration between chemistry faculty
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To develop information literacy skills in chemistry and biochemistry majors at a primarily undergraduate institution, a multiyear collaboration between chemistry faculty and librarians has resulted in the establishment of a semester-long capstone project for Organic Chemistry II. Information literacy skills were instilled via a progressive research report, supported by a comprehensive modular virtual tutorial catered toward Rider University students, on the efficient use of SciFinder and related tasks for searching and using the primary literature. Over a six-year period, both the research report and the tutorial modules have been cyclically evaluated, assessed, and revised in order to meet our student learning objectives. This article describes the assessment-driven evolution of the research report assignment between 2010 and 2015, as well as student perceptions and learning outcomes. The technological development, feedback-driven revisions, and assessment of student learning outcomes of the SciFinder tutorial series have been included in a companion article in this Journal . ACS Electronic Supporting Info
- Kinetic model for modern double-layered Pd/Rh TWC as a function of metal loadings and mileage
- Kang, S.B., Nam, I.S., Cho, B.K., Kim, C.H., Oh, S.H. | Chemical engineering journal (v.278 / pp.328-338 / 20151385-8947)
- The overall reaction kinetics for a modern double-layered Pd/Rh bimetallic TWC has been developed by combining the activity functions derived separately for the Pd-based
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The overall reaction kinetics for a modern double-layered Pd/Rh bimetallic TWC has been developed by combining the activity functions derived separately for the Pd-based (a Pd ) and Rh-based (a Rh ) TWCs with their respective reference reaction kinetics. A 3D activity function for the commercial Rh-based TWC (a Rh ) was developed on the basis of the metal surface area (MSA) of Rh, and subsequently used in combination with the detailed reaction kinetics of the Rh reference catalyst in predicting the catalytic performance variation with respect to the Rh loading from 2.5 to 15g/ft 3 and the catalyst mileage from 4k to 100kmiles obtained from the laboratory aging program. Finally, the catalytic performance of a modern double-layered Pd80/Rh10 TWC monolith reactor was predicted with a reasonable accuracy over a wide range of the catalyst mileage from 4k to 100k by using the overall reaction kinetics for Rh developed in this work along with that for Pd developed previously. The excellent capability of the overall reaction kinetic model in predicting the catalytic performance of the Pd/Rh bimetallic TWC is attributable to the successful combination of the accurate initial activity profiles of Pd and Rh at 4kmiles, the accurate characterization of the deactivation kinetics of Pd and Rh, the detailed surface reaction kinetics employed, and the spatial separation of Pd and Rh particles in a double-layered catalyst configuration.
- Review on High Valent FeVI (Ferrate): A Sustainable Green Oxidant in Organic Chemistry and Transformation of Pharmaceuticals
- Sharma, Virender K., Chen, Long, Zboril, Radek | ACS sustainable chemistry et engineering (v.4 / no.1 / pp.18-34 / 2016)
- Iron is the most common metal by mass on earth and represents the basic element of industrial society. The usage of iron to synthesize consumer products and to remediate
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Iron is the most common metal by mass on earth and represents the basic element of industrial society. The usage of iron to synthesize consumer products and to remediate environment is an attractive approach. This perspective presents applications of the high-valent iron oxo compound Fe VI O 4 2 ndash; (ferrate) in sustainable organic synthesis and treatment technology. In synthesizing organic molecules, C ndash;H bond activation and selectivity are two basic ingredients of efficiency, which are attainable by ferrate. Examples of hydroxylation of hydrocarbons and conversion of alcohols to aldehyde/ketone are presented. In addition, many other organic molecules of amines, aniline, phenolic, and thiol functionalities can be oxidized by ferrate. This oxidation chemistry of ferrate is expedient in transforming pharmaceuticals, micropollutants in bodies of water with implications for human and ecological health. A wide range of micropollutants, which are commonly found in drinking water resources and wastewater effluents, can be efficiently oxidized by ferrate on a seconds to minutes time scale. These molecules include endocrine disruptors, antibiotics, beta;-blockers, antidepressants, X-ray contrast media, and cosmetic products. The reaction pathways of transformation of the studied pharmaceuticals are discussed. The results of the evaluation of toxicity of the oxidized products are given. The reduced product of ferrate is the environmentally friendly and magnetic iron(III) oxide. Ferrate, as a green molecule, has true potential in sustainable production of organics and treating emerging pollutants in water. Ferrate performs C minus;H activation and selectivity in sustainable synthesis and oxidizes moieties to detoxify pollutants in environmentally friendly treatment technology. Graphic Abstract ACS Electronic Supporting Info