Home » Comments
Comments on scientific papers
Here you can search and comment any existing scientific paper: use the search functionality to find the paper you want to comment on. The comments will be forwarded to the corresponding article authors (when possible) and all comment subscribers - identified user can invite additional persons to join the discussion about a specific article.
Latest commented articles
Structural basis for substrate specificity and catalysis of human histone acetyltransferase 1, Proceedings of the National Academy of Sciences, 2012, 10.1073/pnas.1114117109
4 Comments → add new, H. Wu, N. Moshkina, J. Min, H. Zeng, J. Joshua, M.-M. Zhou, A. N. Plotnikov
Histone acetyltransferase 1 is the founding member of the histone acetyltransferase superfamily and catalyzes lysine acetylation of newly synthesized histone H4. Here we report a 1.9-Å resolution crystal structure of human histone acetyltransferase 1 in complex with acetyl coenzyme A and histone H4 peptide. The crystal structure reveals that the cofactor and the side chain of lysine 12 of histone H4 peptide are placed in the canyon between the central and C-terminal domains. Histone H4 peptide adopts a well-defined conformation and establishes an extensive set of interactions with the enzyme including invariant residues Glu64 and Trp199, which together govern substrate-binding specificity of histone acetyltransferase 1. Our structure-guided enzyme kinetic study further demonstrates a cumulative effect of the active-site residues Glu187, Glu276, and Asp277 on deprotonation of the ε-amino group of reactive Lys12 for direct attack of the acetyl group of the cofactor.
Statistics of Distinguishable Particles and Resolution of the Gibbs Paradox of the First Kind, Journal of Statistical Physics, 2010, 10.1007/s10955-010-0077-7
12 Comments → add new, Hjalmar Peters
In physics, there are two distinct paradoxes, which are both known as the “Gibbs paradox”. This article is concerned with only one of them: the false increase in entropy, which is calculated from the process of combining two gases of the same kind consisting of distinguishable particles. In the following, this paradox will be referred to as the Gibbs paradox of the first kind (GP1). (Two particles are said to be distinguishable if they are either non-identical, that is, if they have different properties, or if they are identical and there are microstates which change under transposition of the two particles.) The GP1 is demonstrated and subsequently analyzed. The analysis shows that, for (quantum or classical) systems of distinguishable particles, it is generally uncertain of which particles they consist. The neglect of this uncertainty is the root of the GP1. For the statistical description of a system of distinguishable particles, an underlying set of particles, containing all particles that in principle qualify for being part of the system, is assumed to be known. Of which elements of this underlying particle set the system is composed, differs from microstate to microstate. Thus, the system is described by an ensemble of possible particle compositions. The uncertainty about the particle composition contributes to the entropy of the system. Systems for which all possible particle compositions are equiprobable will be called harmonic. Classical systems of distinguishable identical particles are harmonic as a matter of principle; quantum or classical systems of non-identical particles are not necessarily harmonic, since for them the composition probabilities depend individually on the preparation of the system. Harmonic systems with the same underlying particle set are always correlated; hence, for harmonic systems, the entropy is no longer additive and loses its thermodynamic meaning. A quantity derived from entropy is introduced, the reduced entropy, which, for harmonic systems, replaces the entropy as thermodynamic potential. For identical classical particles, the equivalence (in particular with respect to the second law of thermodynamics) between distinguishability and indistinguishability is proved. The resolution of the GP1 is demonstrated applying the previously found results.
Review and Comparison of Power Management Approaches for Hybrid Vehicles with Focus on Hydraulic Drives, Energies, 2014, 10.3390/en7063512
58 Comments → add new, Mohammad Karbaschian, Dirk Söffker, Mohammad Ali Karbaschian
The main advantage of hybrid powertrains is based on the efficient transfer of power and torque from power sources to the powertrain as well as recapturing of reversible energies without effecting the vehicle performance. The benefits of hybrid hydraulic powertrains can be better utilized with an appropriate power management. In this paper, different types of power management algorithms like off-line and on-line methods are briefly reviewed and classified. Finally, the algorithms are evaluated and compared. Therefore, different related criteria are evaluated and applied.
What Studies of Retractions Tell Us, Journal of Microbiology & Biology Education, 2014, 10.1128/jmbe.v15i2.855
2 Comments → add new, Adam Marcus, Ivan Oransky
The retraction is receiving a growing amount of attention as an important event in scientific and scholarly publishing. Not only are some journals becoming increasingly open in their handling of the articles they withdraw-allowing researchers to gain important insights into the work of their colleagues-but scholars, too, have greater access to the reasons for retractions, information that is dramatically reshaping our understanding of such events. As this article will demonstrate, recent research has inverted the accepted lore about why retractions happen and their impact.
3 Comments → add new, Dumitru Pavel
Techno-Economic Evaluation of Biodiesel Production from Waste Cooking Oil—A Case Study of Hong Kong, International Journal of Molecular Sciences, 2015, 10.3390/ijms16034362
13 Comments → add new, Sanjib Karmee, Raffel Patria, Carol Lin
Fossil fuel shortage is a major challenge worldwide. Therefore, research is currently underway to investigate potential renewable energy sources. Biodiesel is one of the major renewable energy sources that can be obtained from oils and fats by transesterification. However, biodiesel obtained from vegetable oils as feedstock is expensive. Thus, an alternative and inexpensive feedstock such as waste cooking oil (WCO) can be used as feedstock for biodiesel production. In this project, techno-economic analyses were performed on the biodiesel production in Hong Kong using WCO as a feedstock. Three different catalysts such as acid, base, and lipase were evaluated for the biodiesel production from WCO. These economic analyses were then compared to determine the most cost-effective method for the biodiesel production. The internal rate of return (IRR) sensitivity analyses on the WCO price and biodiesel price variation are performed. Acid was found to be the most cost-effective catalyst for the biodiesel production; whereas, lipase was the most expensive catalyst for biodiesel production. In the IRR sensitivity analyses, the acid catalyst can also acquire acceptable IRR despite the variation of the WCO and biodiesel prices.
3D Radiation Therapy Boost Improves the Outcome of Whole Brain Radiation Therapy Treated RPA II Patients with One or Two Brain Metastases, International Journal of Molecular Sciences, 2014, 10.3390/ijms15057554
28 Comments → add new, Delphine Antoni, Jean-Baptiste Clavier, Marius Pop, Catherine Schumacher, François Lefebvre, Georges Noël
Purpose: to evaluate the role of whole brain radiotherapy (WBRT) and radiation boost (RB) for 208 patients recursive partitioning analysis (RPA) II with 1 or 2 brain metastases (BM) at a single institution. Methods and Materials: the dose of WBRT was 30 Gy (10 fractions of 3 Gy). One hundred thirty-two patients (63.5%) benefited from RB of 9 Gy in 3 fractions of 3 Gy at the metastatic site. Patients had 1 or 2 BM in 122 (58.7%) and 86 cases (41.3%), respectively. Results: patients with one or two metastases had similar survival (4.6 and 5.1 months, respectively) (p = 0.4). Median overall survival (OS) for patients treated with WBRT and RB, and with WBRT alone was 5.9 and 3.7 months, respectively (p = 0.03). The 6-, 12- and 24-month OS rates after WBRT and RB were 48.5%, 25% and 10.6%, respectively, while WBRT alone resulted in OS rates of 34%, 22.4% and 3.2%, respectively (p = 0.03). After WBRT and RB, the 6-, 12- and 24-month local control rates were 92%, 82% and 67%, respectively, while they were 81.2%, 75% and 37.5%, respectively, after WBRT alone (p = 0.03). The 6-, 12- and 24-month brain control rates after WBRT and RB were 88.7%, 75.8% and 62%, respectively, and after WBRT alone they were 78.5%, 59% and 37.7%, respectively (p = 0.03). Conclusion: additional boost delivered with 3D conformal radiotherapy improves local and brain control rates significantly as well as overall survival for RPA II patients with 1 or 2 unresectable BM.
Comment on “The Gibbs paradox and the distinguishability of identical particles,” by M. A. M. Versteegh and D. Dieks [Am. J. Phys. 79, 741–746 (2011)], American Journal of Physics, 2012, 10.1119/1.3657773
5 Comments → add new, David S. Corti
[Evaluation of urine acidification ability in patients with systemic lupus erythematosus]., Polish Archives of Internal Medicine, 1976, 10555
10 Comments → add new, B Raszeja-Wanic, D Pupek-Musialik, M Wierzchowiecki
The Gibbs Paradox Revisited, Explanation, Prediction, and Confirmation, 2011, 10.1007/978-94-007-1180-8_25
6 Comments → add new, Dennis Dieks, Dennis Dieks, Wenceslao J. Gonzalez, Stephan Hartmann, Thomas Uebel, Marcel Weber
The Gibbs paradox has frequently been interpreted as a sign that particles of the same kind are fundamentally indistinguishable; and that quantum mechanics, with its identical fermions and bosons, is indispensable for making sense of this. In this article we shall argue, on the contrary, that analysis of the paradox supports the idea that classical particles are always distinguishable. Perhaps surprisingly, this analysis extends to quantum mechanics: even according to quantum mechanics there can be distinguishable particles of the same kind. Our most important general conclusion will accordingly be that the universally accepted notion that quantum particles of the same kind are necessarily indistinguishable rests on a confusion about how particles are represented in quantum theory.