Symmetry breaking by quantum coherence in single electron attachment

Quantum coherence-induced effects in atomic and molecular systems are the basis of several proposals for laser-based control of chemical reactions. So far, these rely on coherent photon beams inducing coherent reaction pathways that may interfere with one another, in order to achieve the desired outcome. This concept has been successfully exploited for removing the inversion symmetry in the dissociation of homonuclear diatomic molecules, but it remains to be seen if such quantum coherent effects can also be generated by interaction of incoherent electrons with such molecules. Here we show that resonant electron attachment to H2 and the subsequent dissociation into H (n=2) + H− is asymmetric about the inter-nuclear axis, while the asymmetry in D2 is far less pronounced. We explain this observation as due to attachment of a single electron resulting in a coherent superposition of two resonances of opposite parity. In addition to exemplifying a new quantum coherent process, our observation of coherent quantum dynamics involves the active participation of all three electrons and two nuclei, which could provide new tools for studying electron correlations as a means to control chemical processes and demonstrates the role of coherent effects in electron induced chemistry

The Canon Wars

Canons are taking their turn down the academic runway in ways that no one would have foretold just a decade ago. Affection for canons of construction has taken center stage in recent Supreme Court cases and in constitutional theory. Harvard Dean John Manning and originalists Will Baude and Stephen Sachs have all suggested that principles of “ordinary interpretation” including canons should inform constitutional interpretation. Given this newfound enthusiasm for canons, and their convergence in both constitutional and statutory law, it is not surprising that we now have two competing book-length treatments of the canons—one by Justice Scalia and Bryan Garner, Reading Law, and the other by Yale Law Professor William N. Eskridge, Interpreting Law. Both volumes purport to provide ways to use canons to read statutes and the Constitution. In this Review of Interpreting Law, we argue that this contemporary convergence on canons raises some significant interpretive questions about judicial power and the very idea of a canon

Molecular Dynamics-Based Strength Estimates of Beta-Solenoid Proteins

The use of beta-solenoid proteins as functionalizable, nanoscale, self-assembling molecular building blocks may have many applications, including templating the growth of wires or higher-dimensional structures. By understanding their mechanical strengths, we can efficiently design the proteins for specific functions. We present a study of the mechanical properties of seven beta-solenoid proteins using GROMACS molecular dynamics software to produce force/torque-displacement data, implement umbrella sampling of bending/twisting trajectories, produce Potentials of Mean Force (PMFs), extract effective spring constants, and calculate rigidities for two bending and two twisting directions for each protein. We examine the differences between computing the strength values from force/torque-displacement data alone and PMF data, and show how higher precision estimates can be obtained from the former. In addition to the analysis of the methods, we report estimates for the bend/twist persistence lengths for each protein, which range from 0.5-3.4 $\mu$m. We note that beta-solenoid proteins with internal disulfide bridges do not enjoy enhanced bending or twisting strength, and that the strongest correlate with bend/twist rigidity is the number of hydrogen bonds per turn. In addition, we compute estimates of the Young's modulus ($Y$) for each protein, which range from $Y$ = 3.5 to 7.2 GPa

ADZ: Analysis of the World Wide Web

The hardware and architecture approach to Smalltalk is defined not only by the refinement of architecture, but also by the important need for red-black trees [13]. After years of confirmed research into web browsers, we prove the under- standing of robots, which embodies the essential principles of interactive cryptography. In this paper we use amphibious communication to dis- confirm that suffix trees and systems can interact to answer this issue

Dissociative Electron Attachment Cross Sections for H₂ and D₂

New measurements of the absolute cross sections for dissociative electron attachment (DEA) in molecular hydrogen and deuterium are presented which resolve previous ambiguities and provide a test bed for theory. The experimental methodology is based upon a momentum imaging time-of-flight spectrometer that allowed us to eliminate any contributions due to electronically excited metastable neutrals and ultraviolet light while ensuring detection of all the ions. The isotope effect in the DEA process in the two molecules is found to be considerably larger than previously observed. More importantly, it is found to manifest in the polar dissociation process (also known as ion pair production) as well

Integrated nutrient management and LCC based nitrogen management on soil fertility and yield of rice (Oryza Sativa L.)

The experiment was conducted at lowland series of wet lands, International Rice Research Institute (IRRI) Farm, Los Banos, Laguna, Philippines. The rice variety PSBRc 82 was raised during wet season (June – October), and the experiment was laid out in randomized block design with four replications. There were eleven treatments viz., control, recommended NPK fertilizer, -N, -P, -K, LCC 3, LCC 4, LCC 5, 100% N as fresh rice straw, 50% N through rice straw compost and 50% N as poultry manure and 50% N as combined organic manures (RSC + PM). The P and K were applied to all the treatments except -P and –K treatments, respectively. The fertilizer N @ 90 kg ha-1, P2O5 @ 40 kg ha-1 and K2O @ 60 kg ha-1 were applied in the form of urea, super phosphate and muriate of potash respectively. The application of N at 90 kg level as 50% through RSC + 50% N as PM registered higher available N, P and K contents of soil during different growth stages as compared to the other treatment combinations including recommended NPK fertilizers. The growth and yield attributes were also found to be improved by the above treatment resulting in more grain and straw yield. With regard to N management, LCC 4 and 5 based N applications recorded higher grain yield as a result of higher soil available nutrients during the critical growth stages.Srinivasagam Krishnakumar and Stephan Haefel

X-ray photoemission study of NiS_{2-x}Se_x (x = 0.0 - 1.2)

Electronic structure of NiS_{2-x}Se_x system has been investigated for various compositions (x) using x-ray photoemission spectroscopy. An analysis of the core level as well as the valence band spectra of NiS_2 in conjunction with many-body cluster calculations provides a quantitative description of the electronic structure of this compound. With increasing Se content, the on-site Coulomb correlation strength (U) does not change, while the band width W of the system increases, driving the system from a covalent insulating state to a pd-metallic state.Comment: 19 pages, 6 figures, To appear in Phys. Rev. B, 200