What College Students Learn from Teaching Others

This article describes what undergraduate students learned from participating in a museum docent program at a large, public university on the West Coast of the United States. The majority (93%) of students report an increase in their ability to effectively communicate specialized knowledge to museum visitors in one or more of the following ways: 1) identifying what visitors know and adjusting their explanations accordingly; 2) translating technical information to visitors; 3); communicating information in an active, hands-on manner; 4) confidently communicating their knowledge to others. Students reported personal and professional benefits as well. In addition to this focused observation approach, student reflections were analyzed for two pre-identified themes. Benefits reported by student docents can be realized by other undergraduate students teaching in contexts other than a museum, as long as students doing the teaching receive frequent feedback, fulfill an authentic need among those whom they teach, and take time to reflect on their teaching experiences. Archaeologists who want their students to achieve key learning goals such as effective communication can help students reach these goals by providing them with opportunities to teach what they have learned to others

Dual Status and Adultification: Black Girls\u27 Lives in Context

In the United States, Black youth are consistently overrepresented in the child welfare and juvenile carceral systems. However, Black girls represent an invisible population whose lived experiences are historically devalued and silenced. Scholars have begun to explore Black girls in the child welfare and juvenile justice systems, the adultification of Black girls, and the lives of crossover or dual-status youth[1]. That is, youth who have been involved in both the juvenile and the child welfare systems simultaneously or at different periods. Previous research on crossover youth has focused on young boys—primarily Black and Latino males—from the perspective of professionals, program models, and interventions rather than from youth and their experiences. Furthermore, there is a lack of understanding about how adultification impacts Black girls’ lives in these dual systems (i.e., child welfare and juvenile justice). Thus, the purpose of this contextualization is to examine the role of adultification in the experiences of Black girls with dual status using two theoretical frameworks: critical race feminism and intersectionality. To accomplish this goal, the paper begins by exploring the literature on identity development, discrimination, and bias among Black girls who have experiences in one or both systems. Next, the consequences of crossover or dual-status youth are discussed. Using critical race feminism and intersectionality, the author explored how adultification for Black girls with dual status may create unique experiences different from their peers. Suggestions for future research, policy, and practice are provided to aid social work leaders, researchers, and legal professionals in better serving this population, through an antiracist lens, and further the empowerment of, and advocacy for, Black girls. [1] Crossover youth and dual status youth are both terms used to describe this population. For the purposes of this paper, the term dual status will be used

Discriminating cool-water from warm-water carbonates and their diagenetic environments using element geochemistry: the Oligocene Tikorangi Formation (Taranaki Basin) and the dolomite effect

Fields portrayed within bivariate element plots have been used to distinguish between carbonates formed in warm- (tropical) water and cool- (temperate) water depositional settings. Here, element concentrations (Ca, Mg, Sr, Na, Fe, and Mn) have been determined for the carbonate fraction of bulk samples from the late Oligocene Tikorangi Formation, a subsurface, mixed dolomite-calcite, cool-water limestone sequence in Taranaki Basin, New Zealand. While the occurrence of dolomite is rare in New Zealand Cenozoic carbonates, and in cool-water carbonates more generally, the dolomite in the Tikorangi carbonates is shown to have a dramatic effect on the "traditional" positioning of cool-water limestone fields within bivariate element plots. Rare undolomitised, wholly calcitic carbonate samples in the Tikorangi Formation have the following average composition: Mg 2800 ppm; Ca 319 100 ppm; Na 800 ppm; Fe 6300 ppm; Sr 2400 ppm; and Mn 300 ppm. Tikorangi Formation dolomite-rich samples (>15% dolomite) have average values of: Mg 53 400 ppm; Ca 290 400 ppm; Na 4700 ppm; Fe 28 100 ppm; Sr 5400 ppm; and Mn 500 ppm. Element-element plots for dolomite-bearing samples show elevated Mg, Na, and Sr values compared with most other low-Mg calcite New Zealand Cenozoic limestones. The increased trace element contents are directly attributable to the trace element-enriched nature of the burial-derived dolomites, termed here the "dolomite effect". Fe levels in the Tikorangi Formation carbonates far exceed both modern and ancient cool-water and warm-water analogues, while Sr values are also higher than those in modern Tasmanian cool-water carbonates, and approach modern Bahaman warm-water carbonate values. Trace element data used in conjunction with more traditional petrographic data have aided in the diagenetic interpretation of the carbonate-dominated Tikorangi sequence. The geochemical results have been particularly useful for providing more definitive evidence for deep burial dolomitisation of the deposits under the influence of marine-modified pore fluids

Information dynamics in cavity QED

A common experimental setup in cavity quantum electrodynamics (QED) consists of a single two-level atom interacting with a single mode of the electromagnetic field inside an optical cavity. The cavity is externally driven and the output is continuously monitored via homodyne measurements. We derive formulas for the optimal rates at which these measurements provide information about (i) the quantum state of the system composed of atom and electromagnetic field, and (ii) the coupling strength between atom and field. We find that the two information rates are anticorrelated.Comment: 11 pages, 1 figure, final versio

γ Heavy Chain Disease in Man: cDNA Sequence Supports Partial Gene Deletion Model

Human gamma heavy chain disease (HCD) is characterized by the presence in serum of a short monoclonal Ig gamma chain unattached to light chains. Although most HCD proteins have internal deletions, in some the defect is NH2-terminal. The OMM gamma 3 HCD serum protein is of the latter type, having undergone an extensive NH2-terminal deletion with a sequence starting within the hinge. A cell line synthesizing the OMM protein has enabled us to study the biogenesis of the abnormal molecule. In vitro translation of isolated mRNA yields a protein containing a hydrophobic NH2-terminal leader sequence. In the intact cell, the precursor molecule is processed normally to yield a protein with an NH2-terminal sequence homologous to the beginning of the variable (V) region. The nucleotide sequence of cDNA prepared from the OMM mRNA encodes a 19-amino acid leader followed by the first 15 residues of the V region. An extensive internal deletion encompasses the remainder of the V and the entire CHl domain. Immediately following the short V region, there is information in the cDNA for the entire normal hinge. The primary synthetic product is thus an internally deleted molecule that undergoes postsynthetic degradation to yield the NH2-terminally deleted serum protein. The structure of the OMM mRNA suggests that the protein abnormality results from a partial gene deletion rather than defective splicing

Electric Flight Systems

Materials illustrating presentations on the development of electric flight systems for the all-electric aircraft and for spacecraft are presented

Building one molecule from a reservoir of two atoms

Chemical reactions typically proceed via stochastic encounters between reactants. Going beyond this paradigm, we combine exactly two atoms into a single, controlled reaction. The experimental apparatus traps two individual laser-cooled atoms (one sodium and one cesium) in separate optical tweezers and then merges them into one optical dipole trap. Subsequently, photoassociation forms an excited-state NaCs molecule. The discovery of previously unseen resonances near the molecular dissociation threshold and measurement of collision rates are enabled by the tightly trapped ultracold sample of atoms. As laser-cooling and trapping capabilities are extended to more elements, the technique will enable the study of more diverse, and eventually more complex, molecules in an isolated environment, as well as synthesis of designer molecules for qubits

How is helicity (and twist) partitioned in magnetohydrodynamic simulations of reconnecting magnetic flux tubes?

Funding: STFC through the Consolidated grant, ST/N000609/1, to the University of St Andrews.Magnetic helicity conservation provides a convenient way to analyze specific properties (namely, the linkage and twist) of reconnecting flux tubes and yield additional insight into the pre- and post-reconnection states of magnetic structures in the solar atmosphere. A previous study considered two flux tubes with footpoints anchored in two parallel planes. They showed that reconnection would add self-helicity equivalent to a half turn of twist to each flux tube. We address a related and fundamental question here: if two flux tubes anchored in a single plane reconnect, what are the resulting twists imparted to each of the reconnected tubes? Are they equal and do they have a simple exact value independent of footpoint location? To do this, we employ a new (computationally efficient) method which subdivides each flux tube into distinct elements and calculates the mutual helicity of many elemental pairs, the sum of which determines the self-helicity of the overall flux tube. Having tested the method using a simple analytical model, we apply the technique to a magnetohydrodynamic simulation where initially untwisted magnetic flux tubes are sheared and allowed to reconnect (based on a previous reconnection model). We recover values of self-helicity and twist in the final end state of the simulations which show excellent agreement with theoretical predictions.Publisher PDFPeer reviewe