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The article focuses on how an initiative in Massachusetts to prioritize skill-based hiring over college degrees inadvertently led to concerns that certified rehabilitation counselors might not be able to disclose their credentials to clients, posing challenges for both counselors.

Close collaboration on the part of the engineers and architects of the new San Francisco Federal Building has created a facility that advances the goals of sustainable development by incorporating features that maximize the use of natural ventilation and natural lighting. The iconic structure is considered a model for future federal buildings.

The Frederic C. Hamilton Building — an extension of the Denver Art Museum — is the first large-scale structure designed by architect Daniel Libeskind to be constructed in the United States. The challenge for the structural engineers was how to tie together the diagonal walls of the crystalline structure both during and after construction.

Geological and geophysical investigations for a nuclear power plant (NORCO) on the north-central coast of Puerto Rico indicate that the proposed site is structurally suitable and free of late Quaternary faults. However, conflicting interpretation of erosional geomorphic features, primarily nips, terraces and caves cut in coastal eolianities and jointed Tertiary carbonates a few to 10 m above sea level, suggest the possibility of non-fault related epeirogeny as young as Holocene in age. Seven peat samples cored from Ciénaga Tiburones, a coastal marsh within the site area, and three wood samples from near-coast fluvial sediments at Arecibo and San Juan, yielded radiocarbon dates ranging in age from about 1,200 to 8,700 years BP. The age and depth associations of these dated sediments fall within or slightly below an envelope defining the maximum oscillatory points of 15 world-wide, Holocene sea level curves. The relationship of the Puerto Rico and world-wide curves suggests no measurable epeirogenic uplift of the north-central coast for at least the last 10,000 years. Coastal caves and terraces above present sea level thus owe their origin to pre-Holocene high stands, or to cave collapse, storm surge, and other modern processes capable of producing erosional features above present tidal range. The analysis of Holocene geological data for north-central Puerto Rico may be a useful technique applicable for siting coastal nuclear power plants elsewhere in the world. Les études géologiques et géophysiques effectuées dans le centre de la côte nord de l’íle de Porto-Rico, en vue de la construction d’une centrale nucléaire montrent que le site proposé a une structure convenable et qu’il n’est pas affecté par des failles quaternaires récentes. Cependant, une interprétation discutable de caractères morphologiques dus à l’érosion, principalement des étranglements, des terrasses et des cavernes, découpées dans des formations éoliennes côtières et dans des carbonates tertiaires fissurés, entre quelques mètres et dix mètres au-dessus du niveau de la mer, suggère la possibilité d’une épéirogénie sans faille aussi récente que l’Holocene. Sept échantillons de tourbe, carottés à Ciénaga Tiburones, un marais côtier situé dans le secteur étudié, et trois échantillons de bois provenant de sédiments fluviatiles proches de la côte, à Arecibo et à San Juan, ont donné des ãges au carbone 14 compris entre 1200 et 8700 ans BP environ. Pour ces sédiments datés, les points représentatifs de l’âge en fonction de la profondeur se situent dans une enveloppe définie par les points maximaux des courbes représentant les oscillations du niveau de la mer à l’Holocène en 15 sites répartis dans le monde entier, ou légèrement au-dessous de cette enveloppe. Les relations entre les courbes de Porto Rico et celles d’autres points du monde suggèrent qu’il n’y a pas eu de soulèvement épéirogénique mesurable dans le centre de la côte nord depuis au moins 10 000 ans. Aussi les cavernes et terrasses côtières au-dessus du niveau actuel de la mer doivent elles s’expliquer par des niveaux élevés atteints par la mer avant l’Holocène ou par des effondrements de cavernes, des vagues de tempête ou d’autres phénomènes récents pouvant produire des figures d’érosion au-dessus du niveau actuel des marées. L’analyse des données géologiques concernant l’Holocène du centre de la côte nord de Porto Rico peut constituer une méthode pratique applicable au choix du site d’une centrale nucléaire côtière en d’autres points du monde.

A microcolony technique is described for measuring epidermal cell survival 3 days after whole-body X-irradiation. This assay provides a cell D0 value of 233 ± 11 rad and a zero-dose extrapolate of 1·23 × 104 cells/cm2 for mice irradiated in oxygen 20 hours after hair plucking. The microcolony cellularity had an apparent doubling-time of 25 hours which may be an upper limit at least for some clones. The clones appeared to fragment continually and form new daughter clones, suggesting that few would form macroscopic nodules. Many of the clones were also apparently associated with hair follicles.

The article focuses on the design and construction of the Frederic C. Hamilton Building as an addition to the Denver Art Museum in Colorado. The Hamilton Building serves as the new grand entrance into the art museum complex. A joint venture of Studio Daniel Libeskind and Davis Partnership was selected to design the building in the summer of 2000. Extremely detailed three-dimensional (3D) construction procedures were developed prior to the start of steel erection.