Collective correlations in C12

The strong coupling of the giant resonance to the surface vibrations in C12 results in the splitting of the single one-particle, one-hole, 1- collective state into several components, thus improving the agreement between theory and experiment to a very large extent

Collective correlations in spherical nuclei and the structure of giant resonances

The theory of collective correlations in nuclei is formulated for giant resonances interacting with surface vibrations. The giant dipole states are treated in the particle-hole framework, while the surface vibrations are described by the collective model. Consequently, this treatment of nuclear structure goes beyond both the common particle-hole model (including its various improvements which take ground-state correlations into account) and the pure collective model. The interaction between giant resonances and surface degrees of freedom as known from the dynamic collective theory is formulated in the particle-hole language. Therefore, the theory contains the particle-hole structures and the most important "collective intermediate" structures of giant resonances. Detailed calculations are performed for 12C, 28Si, and 60Ni. A good detailed agreement between theory and experiment is obtained for all these nuclei, although only 60Ni is in the region where one would expect the theory to work well (50< A <110)

Ion exchange in exfoliated vermiculite

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Limpets and Their Algal Epibionts: Costs and Benefits of Acrosiphonia

Epibiont and basibiont relationships can have positive and negative effects on both organisms involved, ranging in intensity from minor to major effects. Limpets of species Lottia pelta are commonly found with two algal species growing on their backs, Ulva lactuca and Acrosiphonia spp. Previous research has shown that basibionts (substrate organism) and epibionts (organism growing on the surface) have complex interactions that can be positive, negative, or neutral. A force transducer and flume were used to measure the drag forces experienced by a limpet at various water velocities. Presence of either epiphyte significantly increased limpet drag. Acrosiphonia produced a greater drag effect than U. lactuca, increasing the force substantially. When dropped in a tank, limpets with algal growth landed foot-down significantly more often than limpets without algal growth. Acrosiphonia spp. had a greater effect than Ulva lactuca. Lastly, limpets in a wind tunnel with algal growth (especially Acrosiphonia) had cooler body temperatures than limpets without algal growth. In conclusion, the effects on the basibiont of this relationship were found to be both positive and negative

Interacting with Masculinities: A Scoping Review

Gender is a hot topic in the field of human-computer interaction (HCI). Work has run the gamut, from assessing how we embed gender in our computational creations to correcting systemic sexism, online and off. While gender is often framed around women and femininities, we must recognize the genderful nature of humanity, acknowledge the evasiveness of men and masculinities, and avoid burdening women and genderful folk as the central actors and targets of change. Indeed, critical voices have called for a shift in focus to masculinities, not only in terms of privilege, power, and patriarchal harms, but also participation, plurality, and transformation. To this end, I present a 30-year history of masculinities in HCI work through a scoping review of 126 papers published to the ACM Human Factors in Computing Systems (CHI) conference proceedings. I offer a primer and agenda grounded in the CHI and extant literatures to direct future work.Comment: 12 page

Growth and Feeding Studies on the Algal Feeding Stage of a Pfiesteria-like Dinoflagellate

The dinoflagellate Cryptoperidiniopsis sp. was isolated from sediment samples taken from Virginia estuaries, and established in culture for subsequent growth and feeding studies. The maximum abundance, or yield, of Cryptoperidiniopsis is exponentially related to the concentration of algal prey and is saturated at about 4.00 X 105 mL-1. Salinity from 10-20 ppt and temperature between 15-25 C have no effect on the yield of this form of Cryptoperidiniopsis. Light intensity has a secondary effect in that the algal prey reproduces more quickly in higher light as they are being grazed. Growth rates of Cryptoperidiniopsis were highest with a cryptophyte, Cryptomonas, as food, but growth was also demonstrated utilizing both diatoms and chlorophytes. Cryptoperidiniopsis sp. is similar to Pfiesteria in that it feeds myzocytotically with a peduncle, is similar in size and shape, has a complex life cycle, and is distinguished only by plates hidden under membranes

Growth and Feeding Studies on the Algal Feeding Stage of a Pfiesteria-like Dinoflagellate

The dinoflagellate Cryptoperidiniopsis sp. was isolated from sediment samples taken from Virginia estuaries, and established in culture for subsequent growth and feeding studies. The maximum abundance, or yield, of Cryptoperidiniopsis is exponentially related to the concentration of algal prey and is saturated at about 4.00 X 105 mL-1. Salinity from 10-20 ppt and temperature between 15-25 C have no effect on the yield of this form of Cryptoperidiniopsis. Light intensity has a secondary effect in that the algal prey reproduces more quickly in higher light as they are being grazed. Growth rates of Cryptoperidiniopsis were highest with a cryptophyte, Cryptomonas, as food, but growth was also demonstrated utilizing both diatoms and chlorophytes. Cryptoperidiniopsis sp. is similar to Pfiesteria in that it feeds myzocytotically with a peduncle, is similar in size and shape, has a complex life cycle, and is distinguished only by plates hidden under membranes