The acoustic designer: Joining soundscape and architectural acoustics in architectural design education

This article discusses the integration of acoustic design approaches into architectural design education settings. Solving architectural acoustic problems has been for centuries one of the primary aims of theories and experiments in acoustics. Recent contributions offered by the soundscape approach have highlighted broader desirable aims which acoustic designers should pursue, fostering ecological reasoning on the acoustic environment and its perception as a whole. Drawing from the available literature, some examples are brought to show the integration of architectural acoustics and soundscape approaches into the realm of architectural design education, highlighting the significance of specific design situations and aural training techniques in learning contexts

Paradigms for computational nucleic acid design

The design of DNA and RNA sequences is critical for many endeavors, from DNA nanotechnology, to PCR‐based applications, to DNA hybridization arrays. Results in the literature rely on a wide variety of design criteria adapted to the particular requirements of each application. Using an extensively studied thermodynamic model, we perform a detailed study of several criteria for designing sequences intended to adopt a target secondary structure. We conclude that superior design methods should explicitly implement both a positive design paradigm (optimize affinity for the target structure) and a negative design paradigm (optimize specificity for the target structure). The commonly used approaches of sequence symmetry minimization and minimum free‐energy satisfaction primarily implement negative design and can be strengthened by introducing a positive design component. Surprisingly, our findings hold for a wide range of secondary structures and are robust to modest perturbation of the thermodynamic parameters used for evaluating sequence quality, suggesting the feasibility and ongoing utility of a unified approach to nucleic acid design as parameter sets are refined further. Finally, we observe that designing for thermodynamic stability does not determine folding kinetics, emphasizing the opportunity for extending design criteria to target kinetic features of the energy landscape

The need for a second black hole at the Galactic center

Deep infra-red observations and long-term monitoring programs have provided dynamical evidence for a supermassive black hole of mass 3.e6 solar masses associated with the radio source Sagitarrius A* at the center of our Galaxy. The brightest stars orbiting within 0.1 parsecs of the black hole appear to be young, massive main sequence stars, n spite of an environment near the black hole that is hostile to star formation. We discuss mechanisms by which stars born outside the central parsec can sink towards the black hole and conclude that the drag coming from plausible stellar populations does not operate on the short timescales required by the stellar ages. We propose that these stars were dragged in by a second black hole of mass of 1.e3-1.e4 solar masses, which would be classified as an intermediate-mass black hole. We discuss the implications for the stellar populations and the kinematics in the Galactic center. Finally we note that continued astrometric monitoring of the central radio source offers the prospect for a direct detection of such objects.Comment: 5 pages, 2 postscript figures, submitted to ApJ letters The introduction section has been updated since submission to Ap

Let Me Share a Thought Series (12 items)

Let Every Soul be Subject (Romans 13:1) Let the Word of Christ Dwell in You Richly (Colossians 3:16) A Lot of Lets -- For Your Encouragement (Psalms 119, 130, 148), April 20, 1976 Let Love Be Without Dissimulation (Romans 12:9) Let Not Him That Eateth Despise (Romans 14:3) Let Not Your Good Be Evil Spoken Of (Romans 14:16) Let Not Your Heart Be Troubled (John 14:1), March 5, 1976 Let Love Guide Your Life, February 27, 1976 Let Me Share a Thought Let the Peace of God Rule (Reign) In Your Heart (Colossians 3:15) Let Patience Have Her Perfect Work (James 1:4) Let Me Share a Though

The Middle Term

Not the January inter-term, but the middle term in the syllogism of life

Tower Topics: Honor and Honors (article for THE ECHO)

In the Taylor program the honor principle is very important, both in our academic life and in the social and spiritual phases of our living. Now I would like to emphasize honors. The honors program has both formal and informal aspects