gebhart/patrepeval huggingface dataset:
Use of Compound-Specific Stable Carbon Isotope Analyses To Demonstrate Anaerobic Biodegradation of MTBE in Groundwater at a Gasoline Release Site (2002)

Currently it is unclear if natural attenuation is an appropriate remedial approach for groundwater impacted by methyl tertiary butyl ether (MTBE). Site-characterization data at most gasoline release sites are adequate to evaluate attenuation in MTBE concentrations over time or distance. But, demonstrating natural biodegradation of MTBE requires laboratory microcosm studies, which could be expensive and time-consuming. Recently, compound-specific carbon isotope ratio analyses (13C/12C expressed in delta13C notation) have been used to demonstrate aerobic biodegradation of MTBE in laboratory incubations. This study explored the potential of this approach to distinguish MTBE biodegradation from other abiotic processes in an anaerobic groundwater plume that showed extensive decrease in MTBE concentrations. To our knowledge, this is the first study to use delta13C of MTBE data in groundwater and laboratory microcosms to demonstrate anaerobic biodegradation of MTBE. The delta13C of MTBE in monitoring wells increased by up to 31 per thousand (-25.5 per thousand to +5.5 per thousand) along with a 40-fold decrease in MTBE concentrations. Anaerobic incubations in laboratory microcosms indicated up to 20-fold reduction in MTBE concentrations with a corresponding increase in delta13C of MTBE of up to 33.4 per thousand (-28.7 per thousand to +4.7 per thousand) in live microcosms. Little enrichment was observed in autoclaved controls. These results demonstrate that anaerobic biodegradation was the dominant natural attenuation mechanism for MTBE at this site. The estimated isotopic enrichment factors (epsilon(field) = -8.10 per thousand and epsilon(lab) = -9.16 per thousand) were considerably larger than the range (-1.4 per thousand to -2.4 per thousand) previously reported for aerobic biodegradation of MTBE in laboratory incubations. These observations strongly suggest that delta13C of MTBE could be potentially useful as an "indicator" of in-situ MTBE biodegradation.
<i>Dynamics of Proteins and Nucleic Acids</i> (1988)

Share Icon Share Twitter Facebook Reddit LinkedIn Reprints and Permissions Cite Icon Cite Search Site Citation J. Andrew Mccammon, Stephen C. Harvey, Peter G. Wolynes; Dynamics of Proteins and Nucleic Acids. Physics Today 1 September 1988; 41 (9): 105–106. https://doi.org/10.1063/1.2811564 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentPhysics Today Search Advanced Search
Rechargeable Zinc Air Batteries and Highly Improved Performance through Potassium Hydroxide Addition to the Molten Carbonate Eutectic Electrolyte (2018)

The zinc air battery has been regarded as an efficient solution to renewable energy storage applications in the next generation. Zinc air chemistries are promising, though great challenges still remain to utilize their high energy, optimize efficiency and high discharge rate. Here, we demonstrate an improved zinc air battery by replacing NaOH, used in our previous study, with KOH as an additive to the molten Li0.87Na0.63K0.50CO3 eutectic electrolyte. Cycling tests showed a very stable performance through 150 charge-discharge cycles, exhibiting high coulombic efficiency (94%) and an average discharge potential of ∼1.08 V when charged at a constant current of 75 mA and discharged over a constant 100Ω load to 0.8 V cutoff at 550°C. Moreover, rate tests revealed a good performance even at high rates of cycling, maintaining a coulombic efficiency of over 90% while at 7.3 C. These results show marked improvements in the field of rechargeable zinc air batteries.
Catalytic Upgrading of Methane to Higher Hydrocarbon in a Nonoxidative Chemical Conversion (2016)

Discovery of large shale gas reserves in recent years resulted in the reduction of natural gas price. In order to convert methane in a direct and energy efficient route, nonoxidative catalytic conversion is a potentially attractive option which includes an activation of methane molecules at low temperature. The oxide of transition metals such as Mo, Fe, V, W, Cr, Zn, and Cu have been studied as catalysts for methane conversion, where usually the conversion is lower than 20% and the operating temperature needed is above 800 °C which causes coking, thus resulting in an early catalyst deactivation. In this work, a noble transition metal, ruthenium, has been chosen as the catalyst with the objective to decrease the methane activation temperature, increase the stability, and also achieve higher conversion than other transition metal catalysts. The catalyst was prepared as 1.5 or 3.0 wt % ruthenium loading on zeolite (i.e., ZSM-5) and silica supports separately to compare the effect of metal loading and metal–support combination on the methane conversion reaction, wherein the operating temperature was varied from 500° to 800 °C. From online GC and FT-IR analyses of the gas products, it was observed that, on the 3.0 wt % Ru/ZSM-5 catalyst bed, a rise in methane conversion took place at 700 °C, where heavy hydrocarbon molecules from C4 to C10 were produced, whereas for the 3.0 wt % Ru/SiO2 catalyst bed, methane conversion was found to be low even at 800 °C and no significant production of higher hydrocarbon molecules was observed. The catalyst bed of 3.0 wt % Ru/ZSM-5 produced some aromatic compounds in liquid product. This could be attributed to the special framework structure in the ZSM-5 catalyst which influenced the formation of cyclic higher hydrocarbon molecules as product after methane is being activated on the surface of the ruthenium metal catalyst. Ruthenium supported on ZSM-5 also produced methyl radicals in a considerable amount at above 700 °C. Furthermore, the origin of the lower-temperature activation effect on transition metals was examined with the density functional theory analyses, which suggests that the zeolite structure lowers the activation energies more than the silica structure by inducing more negative charge on C atom of methane.
The Click Chemistry Approach Applied to Fluorine-18 (2010)

New methods to introduce fluorine-18 into biomolecules are constantly of great interest. Particularly, the increasing number of complex structures poses a challenge to 18F-labelling chemistry. Indirect 18F-labelling procedures using prosthetic groups are commonly used for multifunctional biologically active compounds; however there is continuous demand for new and improved radiofluorination methods. The Cu(I)-catalysed variant of the Huisgen 1,3-dipolar cycloaddition of terminal alkynes and azides represents a most efficient and powerful reaction referred to as click chemistry. This reaction is highly specific and provides excellent yields under very mild conditions. This reaction ideally complies with the requirements of fluorine-18 labelling chemistry. Hence, it offers a convenient and efficient new 18F-fluorination method which is particularly suitable for prosthetic group labelling. The first few reports using the click approach in fluorine- 18 chemistry already demonstrated the particular feasibility of this approach. This review gives an overview of the Cu(I) 1,3-dipolar cycloaddition of terminal alkynes and azides and further describes the first applications of this click reaction in fluorine-18 labelling. Keywords: Click chemistry, 18F-labelling, prosthetic group labeling, fluorine-18, Huisgen 1,3-dipolar cycloaddition
RANK Ligand Is a Therapeutic Target in Multiple Myeloma (2010)

Osteolytic bone disease is a frequent and severe complication of multiple myeloma (MM). MM cells interact with stromal cells in the bone marrow niche to create an environment that is favorable for tumor growth, in particular by inducing differentiation and activity of bone-resorbing osteoclasts, while concomitantly inhibiting differentiation and activity of bone-depositing osteoblasts. This results in a net loss of bone and subsequent skeletal morbidity including fracture, bone pain, and hypercalcemia. RANK ligand (RANKL), a member of the tumor necrosis factor (TNF) cytokine family, is required for differentiation, activation, and survival of osteoclasts and thus plays a critical role in cancer-induced bone disease. Under normal circumstances, RANKL activity is attenuated by its endogenous inhibitor, osteoprotegerin (OPG), a soluble TNF receptor family protein that prevents RANKL from binding to its receptor RANK, expressed on osteoclasts. However, in MM, both RANKL and OPG are dysregulated, resulting in excess RANKL available to stimulate osteoclastic bone resorption. An increased RANKL/OPG ratio is associated not only with the extent of bone disease in patients with MM but also with the prognosis for overall survival. In preclinical models of MM, pharmacologic inhibition of RANKL has been demonstrated to ablate osteoclasts and thus prevent MM-associated bone disease. In addition, RANKL inhibition led to decreased tumor burden in these models, demonstrating the dependence of MM on osteoclast activity. Clinical studies currently underway are evaluating the potential of denosumab, a fully human monoclonal antibody targeting RANKL, to prevent or treat cancer-induced bone disease in MM and other cancer types.
Notes - An Improved Synthesis of 2-Methylpyrrole (1956)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTNotes - An Improved Synthesis of 2-MethylpyrroleP. Cantor, R. Lancaster, and C. VanderWerfCite this: J. Org. Chem. 1956, 21, 8, 918Publication Date (Print):August 1, 1956Publication History Published online27 February 2003Published inissue 1 August 1956https://pubs.acs.org/doi/10.1021/jo01114a605https://doi.org/10.1021/jo01114a605research-articleACS PublicationsRequest reuse permissionsArticle Views821Altmetric-Citations6LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
"Soft limiting" in audio power amplification (1970)

A method of instantaneous automatic compression of large signals, called "soft limiting", generates much less harmonic distortion than uncontrolled clipping. If the audible effect of finite-power output (clipping) is prevented, the effect should be the illusion of greater power reserve while reducing manufacturing costs.
Fuzzy logic based multi-hop broadcast for high-density vehicular ad hoc networks (2010)

Vehicular ad hoc networks have been attracting the interest of both academic and industrial communities on account of their potential role in Intelligent Transportation Systems (ITS). In vehicular ad hoc networks, vehicles are usually located quite densely within the range of radio transmission. In this paper, we propose a fuzzy logic based multi-hop broadcast protocol for information dissemination in high-density vehicular ad hoc networks. The proposed protocol exhibits low message overheads by means of using only a subset of neighbor nodes to relay messages. In the relay node selection, the proposed protocol jointly considers multiple metrics of inter-vehicle distance, node mobility and signal strength by employing the fuzzy logic. We use computer simulations to evaluate the performance of the proposed protocol.
Calcium Orthophosphates in Nature, Biology and Medicine (2009)

The present overview is intended to point the readers’ attention to the important subject of calcium orthophosphates. These materials are of the special significance because they represent the inorganic part of major normal (bones, teeth and dear antlers) and pathological (i.e. those appearing due to various diseases) calcified tissues of mammals. Due to a great chemical similarity with the biological calcified tissues, many calcium orthophosphates possess remarkable biocompatibility and bioactivity. Materials scientists use this property extensively to construct artificial bone grafts that are either entirely made of or only surface-coated with the biologically relevant calcium orthophosphates. For example, self-setting hydraulic cements made of calcium orthophosphates are helpful in bone repair, while titanium substitutes covered by a surface layer of calcium orthophosphates are used for hip joint endoprostheses and as tooth substitutes. Porous scaffolds made of calcium orthophosphates are very promising tools for tissue engineering applications. In addition, technical grade calcium orthophosphates are very popular mineral fertilizers. Thus ere calcium orthophosphates are of great significance for humankind and, in this paper, an overview on the current knowledge on this subject is provided.
Power Gain in Feedback Amplifier (1954)

A linear three-terminal device <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Z</tex> is imbedded in a lossless passive network N and the properties of the complete system, as measured at two specified terminal pairs, are described by the open-circuit impedances <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Z_{11}, Z_{12}, Z_{21},</tex> and <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Z_22</tex> . A search for properties of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Z</tex> which are invariant under the transformation N leads to the quantity <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">U = \frac{|Z_{21}-Z_{12}|^2}{4(R_{11}R_{22}-R_{12}R_{21})}</tex> where <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R_{jk}</tex> is the real part of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Z_{jk}</tex> . Quantity <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">U</tex> is independent of the choice of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">N</tex> and is (consequently) invariant under permutations of the three terminals and also under replacement of the open-circuit impedances by short-circuit admittances. If <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">U</tex> exceeds unity at a specified frequency, then <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">N</tex> can always be chosen to make <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R_{11}</tex> and <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R_{22}</tex> positive and <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Z_{12}</tex> zero at that frequency. Quantity <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">U</tex> is identifiable as the available power gain of the resulting unilateral structure. An arbitrary coupling network may be decomposed into a portion which accomplishes unilateralization and a remaining complementary portion which provides feedback around the unilateralized structure. Such decomposition brings some of the notions of elementary feedback theory to bear upon nonunilateral circuit analysis and offers a viewpoint from which signal flow and power flow are simply related.
The status of engineering in the age of technology: Part II. Principles of practice (2002)

Historians of modern times characterise the world at the beginning of the 21st century as enteringa new era, one principally defined by a constantly advancing technology. The place of the engineerin this new technological society, however, does not seem to be notable to the historical view. Thispaper argues that it is the changing base of industrialisation from production to consumption thathas diminished the prestige and prominence of engineers; for the decision what to make to sell isnot an engineering one. Engineering is now captive to managerial agenda driven by the market,and engineers exercise power only within that mandate. The paper proposes that, if the professionaspires to change this and to play an influential role in developments of this remarkable age, itmust first acknowledge that technological action is now socially constructed. It then has to commititself to rebuilding the foundations of engineering education on the central principles of humanaffairs as well as on its traditional attachment to the physical world. What is needed is nothingshort of a new vision for engineering in the future, a radical shift in the culture of professionalengineering
A Highly Enantio- and Diastereoselective Catalytic Intramolecular Stetter Reaction (2005)

A highly enantio- and diastereoselective intramolecular Stetter reaction has been developed. Subjection of alpha,alpha-disubstituted Michael acceptors to an asymmetric intramolecular Stetter reaction results in a highly enantioselective conjugate addition and a diastereoselective proton transfer. Available evidence suggests the diastereoselective protonation occurs via intramolecular delivery to the sterically more hindered face of the enolate. The scope of the trisubstituted Michael acceptors has been examined and found to be broad with respect to the size of the alpha-substituent and nature of the Michael acceptor. Aliphatic and aromatic aldehydes were examined and found to afford the desired product in good overall yield with high enantio- and diastereoselectivity.
Session-Based Recommender Systems for Action Selection in GUI Test Generation (2020)

Test generation at the graphical user interface (GUI) level has proven to be an effective method to reveal faults. When doing so, a test generator has to repeatably decide what action to execute given the current state of the system under test (SUT). This problem of action selection usually involves random choice, which is often referred to as monkey testing. Some approaches leverage other techniques to improve the overall effectiveness, but only a few try to create human-like actions-or even entire action sequences. We have built a novel session-based recommender system that can guide test generation. This allows us to mimic past user behavior, reaching states that require complex interactions. We present preliminary results from an empirical study, where we use GitHub as the SUT. These results show that recommender systems appear to be well-suited for action selection, and that the approach can significantly contribute to the improvement of GUI-based test generation.
Hypoglycemic Activity of Psidium guajava Linn. Leaf Extract (2004)

Objective: To evaluate the hypoglycemic activity of ethanol extract of Psidium guajava leaves. Materials and methods: The ethanol extract of leaves of Psidium guajava was tested for its hypoglycemic activity in alloxan-induced hyperglycemic Wistar rats. Results: In both acute and sub-acute tests, the ethanol extract, at an oral dose of 250 mg/kg, showed statistically significant and considerable hypoglycemic activity. Conclusion: Psidium guajava leaves possess statistically significant hypoglycemic activity.
Microfluidic force spectroscopy for characterization of biomolecular interactions with piconewton resolution (2010)

In this paper we present a scalable method based on the use of microfluidics and shear force spectroscopy which can be used for determining the affinity between molecules. Our method involves the use of functionalization of the surface of microfluidic channels with ligand molecules, and the surface of microspheres with receptor molecules. Bound beads are detached from the surface of the microchannels using pressure driven flow. The drag force required to detach the beads is used to determine the affinity of the bond holding the two molecules together. The minimum force we are able to detect is 5 pN. We have used this method to determine the binding force between protein-protein interactions and DNA base-pair interactions. We also have shown the ability of this technique to distinguish between strong and weak protein-protein interactions. Using this approach, it may be possible to multiplex an array of these functionalized channels onto a chip and probe the interactions between large varieties of biomolecules.
Synchronized repolarization after defibrillation shocks. A possible component of the defibrillation process demonstrated by optical recordings in rabbit heart. (1992)

A simple model of reentry is used to illustrate how the constant repolarization response, in addition to wave front termination and refractoriness extension, could play a role in the successful termination of fibrillation by electrical shock.
A comparative study of inhaled ciclesonide 160 µg/day and fluticasone propionate 176 µg/day in children with asthma (2006)

Ciclesonide (CIC) is an inhaled corticosteroid (ICS) with high anti-inflammatory activity and low incidence of local and systemic adverse effects. The objective of this study was to compare the efficacy and safety of CIC with fluticasone propionate (FP) in children and adolescents with persistent asthma. This was a 12-week, randomized, double blind, parallel-group study. After a 2-to 4-week baseline period, a total of 556 children (ages 6-15 years) with asthma (forced expiratory volume in 1 sec [FEV(1)], 50% to 90% predicted) were treated twice daily with CIC 80 microg (ex-actuator, equivalent to 100 microg ex-valve) or FP 88 microg (ex-actuator, equivalent to 100 microg ex-valve) administered via a hydrofluoroalkane-propelled metered-dose inhaler. A statistically significant increase from baseline was observed in FEV(1) for both CIC (285 +/- 16 ml) and FP (285 +/- 15 ml) (P < 0.0001 for both) and in morning and evening peak expiratory flow (P < 0.0001 for both). Significant improvements were seen in asthma symptoms, use of rescue medication, and asthma symptom-free days in both treatment groups, without any differences between the treatment groups in changes from baseline. Two FP-treated patients experienced oral candidiasis and one patient experienced voice alteration. Creatinine-adjusted 24-hr urine cortisol levels increased from baseline levels by 10% in the CIC group (P < 0.05) and by 6% in the FP group (not significant). The efficacy and safety of CIC 160 microg/day were comparable to those of FP 176 microg/day in children with asthma.