Visuospatial bootstrapping: spatialized displays enhance digit and nonword sequence learning

Visuospatial bootstrapping describes the observation that performance on a verbal memory task is enhanced by presenting the to‐be‐remembered material in a format with additional embedded spatial information. Thus far, it has only been reported in short‐term memory tasks. Here, we report two experiments assessing the impact of spatial information on the learning of sequences in long‐term memory. Experiment 1 used digits presented within a familiar numeric keypad as stimuli compared against single digits presented in one location. Experiment 2 used novel nonwords, which were either presented in an unchanging arrangement permitting the building‐up of location knowledge or in a constantly changing arrangement. Both experiments demonstrated strong evidence that reliable spatial information facilitated sequence learning, particularly in later sequence positions. It is concluded that the incidental availability of spatialized information during study can facilitate learning of sequences of digits and nonwords. Furthermore, the spatial information can be learned during the task itself and does not need to be preexistent in long‐term knowledge

A Dense Gas Trigger for OH Megamasers

HCN and CO line diagnostics provide new insight into the OH megamaser (OHM) phenomenon, suggesting a dense gas trigger for OHMs. We identify three physical properties that differentiate OHM hosts from other starburst galaxies: (1) OHMs have the highest mean molecular gas densities among starburst galaxies; nearly all OHM hosts have = 10^3-10^4 cm^-3 (OH line-emitting clouds likely have n(H2) > 10^4 cm^-3). (2) OHM hosts are a distinct population in the nonlinear part of the IR-CO relation. (3) OHM hosts have exceptionally high dense molecular gas fractions, L(HCN)/L(CO)>0.07, and comprise roughly half of this unusual population. OH absorbers and kilomasers generally follow the linear IR-CO relation and are uniformly distributed in dense gas fraction and L(HCN), demonstrating that OHMs are independent of OH abundance. The fraction of non-OHMs with high mean densities and high dense gas fractions constrains beaming to be a minor effect: OHM emission solid angle must exceed 2 pi steradians. Contrary to conventional wisdom, IR luminosity does not dictate OHM formation; both star formation and OHM activity are consequences of tidal density enhancements accompanying galaxy interactions. The OHM fraction in starbursts is likely due to the fraction of mergers experiencing a temporal spike in tidally driven density enhancement. OHMs are thus signposts marking the most intense, compact, and unusual modes of star formation in the local universe. Future high redshift OHM surveys can now be interpreted in a star formation and galaxy evolution context, indicating both the merging rate of galaxies and the burst contribution to star formation.Comment: 5 pages, 3 figures, 1 table, accepted by ApJ Letter

Precision Extruding Deposition and Characterization of Cellular Poly-e-Caprolactone Tissue Scaffolds

Successes in scaffold guided tissue engineering require scaffolds to have specific macroscopic geometries and internal architectures in order to provide the needed biological and biophysical functions. Freeform fabrication provides an effective process tool to manufacture many advanced scaffolds with designed properties. This paper reports our recent study on using a novel Precision Extruding Deposition (PED) process technique to directly fabricate cellular Poly-ε-Caprolactone (PCL) scaffolds. Scaffolds with a controlled pore size of 250 µm and designed structural orientations were fabricated. The scaffold morphology, internal micro-architecture and mechanical properties were evaluated using SEM, Micro-Computed Tomography (µ-CT) and the mechanical testing. Preliminary biological study was also conducted to investigate the cell responses to the as-fabricated tissue scaffolds. The results and the characterizations demonstrate the viability of the PED process to the scaffold fabrication as well as a good mechanical property, structural integrity, controlled pore size, pore interconnectivity, and the anticipated biological compatibility of the as-fabricated PCL scaffolds.The authors acknowledge the NSF-0219176 project funding support to graduate students Andrew Darling and Saif Khalil, and the ONR research funding support to graduate student Lauren Shor.Mechanical Engineerin

Charting the value and limits of other effective conservation measures (OECMs) for marine conservation: A Delphi study

Other effective conservation measures (OECMs) will play an important role in the Post-2020 Global Biodiversity Framework as a way for governments to achieve “30 × 30” (30% protection of land and oceans by 2030). However, the policy tool remains relatively new, is expanding from multiple perspectives, and requires clarification. We conducted a Delphi study – a structured technique designed to elicit the insights of a panel of experts – to chart the value and limits of OECMs for marine conservation. Results of the Delphi reveal a high degree of consensus on several core areas of this emerging policy tool. Experts agreed that OECMs can advance equitable and effective conservation. Realizing these opportunities will require strengthening local and Indigenous rights and prioritizing principles of social equity. The panel also agreed on five key challenges, ranging from ensuring that the burden to prove effectiveness does not fall to local communities to securing adequate resources to support OECMs. In contrast, no consensus was reached on how to measure the effectiveness of OECMs, highlighting the need to develop shared monitoring guidelines. Taken together, these findings outline a clear policy and research agenda to support the contributions of OECMs towards equitable, effective, and enduring conservation

New limits for neutrinoless tau decays

Neutrinoless 3-prong tau lepton decays into a charged lepton and either two charged particles or one neutral meson have been searched for using 4.79fb^(-1) of data collected with the CLEO II detector at Cornell Electron Storage Ring. This analysis represents an update of a previous study and the addition of six decay channels. In all channels the numbers of events found are compatible with background estimates and branching fraction upper limits are set for 28 different decay modes. These limits are either more stringent than those set previously or represent the first attempt to find these decays

Examining the context of instruction to facilitate student success

© 2015, © The Author(s) 2015. Identifying effective instructional practices and effective teachers is an important issue in educational research, policy, and practice. However, many schools have resorted to measuring these constructs with student test scores, ignoring the instructional context. In this introductory article to the special issue, we highlight the importance of the instructional context as facilitating of teacher-student relationships, effective instructional practices, and supporting of student success

Inferring Latent Structure From Mixed Real and Categorical Relational Data

We consider analysis of relational data (a matrix), in which the rows correspond to subjects (e.g., people) and the columns correspond to attributes. The elements of the matrix may be a mix of real and categorical. Each subject and attribute is characterized by a latent binary feature vector, and an inferred matrix maps each row-column pair of binary feature vectors to an observed matrix element. The latent binary features of the rows are modeled via a multivariate Gaussian distribution with low-rank covariance matrix, and the Gaussian random variables are mapped to latent binary features via a probit link. The same type construction is applied jointly to the columns. The model infers latent, low-dimensional binary features associated with each row and each column, as well correlation structure between all rows and between all columns

Effects of Dietary Sodium Intake on Blood Flow Regulation During Exercise in Salt Resistant Individuals

PURPOSE: Dietary sodium intake guidelines is ≤2,300 mg/day, yet is exceeded by 90% of Americans. This study examined the impact of a high sodium diet on blood flow regulation during exercise. METHODS: Six males (25 ± 2 years) consumed dietary sodium intake guidelines for two weeks, with one week salt-capsule supplemented (HS: 6,900 mg/day of sodium) and the other week placebo-capsule supplemented (LS: 2,300 mg/day of sodium). At the end of each week, peripheral hemodynamic measurements [blood flow (BF), shear rate (SR), and flow mediated dilation (FMD)/SR)] of the brachial and superficial femoral artery were taken during handgrip (HG) and plantar flexion (PF) exercise, respectively. Each exercise workload was 3 minutes and progressed by 8 kilograms until exhaustion. RESULTS: There were no differences between LS and HS in blood pressure (82 ± 4 v 80 ± 5 mmHg; p = 0.3) or heart rate (56 ± 6 v 59 ± 10 bpm; p = 0.4). HG and PF exercise increased BF, SR, and FMD/SR across workload (p \u3c 0.03 for all), but no difference between diets (p \u3e 0.05 for all). CONCLUSION: Despite previous reports that HS impairs resting vascular function, this study revealed that peripheral vascular function and blood flow regulation during exercise is not impacted by a HS diet.https://scholarscompass.vcu.edu/gradposters/1082/thumbnail.jp