Impact of Seawall Type on Mollusc Size and Diversity in South Water Caye Belize: A Case Study

The size and diversity of molluscs on and in front of artificial and natural sea walls in the tropical rocky intertidal of South Water Caye, Belize were investigated with the intent of determining the suitability of artificial surfaces to replace natural seawalls. Four seawalls, three artificial and one natural, were observed over a period of eight days. Mollusc size did not change based on distance from the wall for any of the walls. However, there were some significant differences in the species and number of molluscs in front of each wall as well as on the walls themselves. Measures of species richness, the Shannon diversity index and Jaccard’s index indicated that the natural wall species assemblage was quite different from that of the artificial walls. For the different types of artificial walls, it was clear that wall structure and age play a role in the number and diversity of molluscs on each wall. This case study has thus revealed that greater attention needs to be dedicated to the architecture and engineering of artificial seawalls in order to minimize their impact on the diversity of molluscs in the marine ecosystem

Temperature and ac Effects on Charge Transport in Metallic Arrays of Dots

We investigate the effects of finite temperature, dc pulse, and ac drives on the charge transport in metallic arrays using numerical simulations. For finite temperatures there is a finite conduction threshold which decreases linearly with temperature. Additionally we find a quadratic scaling of the current-voltage curves which is independent of temperature for finite thresholds. These results are in excellent agreement with recent experiments on 2D metallic dot arrays. We have also investigated the effects of an ac drive as well as a suddenly applied dc drive. With an ac drive the conduction threshold decreases for fixed frequency and increasing amplitude and saturates for fixed amplitude and increasing frequency. For sudden applied dc drives below threshold we observe a long time power law conduction decay.Comment: 6 pages, 7 postscript figure

Recommendations for Effective Integration of Ethics and Responsible Conduct of Research (E/RCR) Education into Course-Based Undergraduate Research Experiences: A Meeting Report.

Advancement of the scientific enterprise relies on individuals conducting research in an ethical and responsible manner. Educating emergent scholars in the principles of ethics/responsible conduct of research (E/RCR) is therefore critical to ensuring such advancement. The recent impetus to include authentic research opportunities as part of the undergraduate curriculum, via course-based undergraduate research experiences (CUREs), has been shown to increase cognitive and noncognitive student outcomes. Because of these important benefits, CUREs are becoming more common and often constitute the first research experience for many students. However, despite the importance of E/RCR in the research process, we know of few efforts to incorporate E/RCR education into CUREs. The Ethics Network for Course-based Opportunities in Undergraduate Research (ENCOUR) was created to address this concern and promote the integration of E/RCR within CUREs in the biological sciences and related disciplines. During the inaugural ENCOUR meeting, a four-pronged approach was used to develop guidelines for the effective integration of E/RCR in CUREs. This approach included: 1) defining appropriate student learning objectives; 2) identifying relevant curriculum; 3) identifying relevant assessments; and 4) defining key aspects of professional development for CURE facilitators. Meeting outcomes, including the aforementioned E/RCR guidelines, are described herein

Light-Ion-Induced Multifragmentation: The ISiS Project

An extensive study of GeV light-ion-induced multifragmentation and its possible interpretation in terms of a nuclear liquid-gas phase transition has been performed with the Indiana Silicon Sphere (ISiS)4 pi detector array. Measurements were performed with 5-15 GeV/c p, pbar, and pion beams incident on $^{197}$Au and 2-5 GeV $^3$He incident on $^{nat}$Ag and $^{197}$Au targets. Both the reaction dynamics and the subsequent decay of the heavy residues have been explored. The data provide evidence for a dramatic change in the reaction observables near an excitation energy of E*/A = 4-5 MeV per residue nucleon. In this region, fragment multiplicities and energy spectra indicate emission from an expanded/dilute source on a very short time scale (20-50 fm/c). These properties, along with caloric curve and scaling-law behavior, yield a pattern that is consistent with a nuclear liquid-gas phase transition.Comment: 67 pages, 44 figures, all included in tar fil

The Genetic Signatures of Noncoding RNAs

The majority of the genome in animals and plants is transcribed in a developmentally regulated manner to produce large numbers of non–protein-coding RNAs (ncRNAs), whose incidence increases with developmental complexity. There is growing evidence that these transcripts are functional, particularly in the regulation of epigenetic processes, leading to the suggestion that they compose a hitherto hidden layer of genomic programming in humans and other complex organisms. However, to date, very few have been identified in genetic screens. Here I show that this is explicable by an historic emphasis, both phenotypically and technically, on mutations in protein-coding sequences, and by presumptions about the nature of regulatory mutations. Most variations in regulatory sequences produce relatively subtle phenotypic changes, in contrast to mutations in protein-coding sequences that frequently cause catastrophic component failure. Until recently, most mapping projects have focused on protein-coding sequences, and the limited number of identified regulatory mutations have been interpreted as affecting conventional cis-acting promoter and enhancer elements, although these regions are often themselves transcribed. Moreover, ncRNA-directed regulatory circuits underpin most, if not all, complex genetic phenomena in eukaryotes, including RNA interference-related processes such as transcriptional and post-transcriptional gene silencing, position effect variegation, hybrid dysgenesis, chromosome dosage compensation, parental imprinting and allelic exclusion, paramutation, and possibly transvection and transinduction. The next frontier is the identification and functional characterization of the myriad sequence variations that influence quantitative traits, disease susceptibility, and other complex characteristics, which are being shown by genome-wide association studies to lie mostly in noncoding, presumably regulatory, regions. There is every possibility that many of these variations will alter the interactions between regulatory RNAs and their targets, a prospect that should be borne in mind in future functional analyses

Place-Based Case Studies: A New Approach to an Effective Teaching Practice

Case-based approaches have been used extensively in STEM classrooms to enhance the real-world applicability of course content. Prior research in the bioeducation field indicates, specifically, that such methods lead to increases in students’ conceptual understanding and affect in the discipline relative to more traditional methods. Despite these outcomes, the majority of case study exercises are formatted in a generalist manner. In other words, the content and context of the case study itself are not framed around the communities in which the students live. In an effort to address this concern, we developed and implemented a series of place-based case study (PBCS) exercises within the introductory cell and molecular biology courses at our institutions. A comparative, quasi-experimental approach was used to evaluate the impact of PBCSs versus non-PBCSs on cognitive and non-cognitive student outcomes. Results indicated that both PBCSs and non-PBCSs led to increases in students’ content knowledge; however, no statistically significant difference existed in post-exercise performance between the PBCS and non-PBCS cohorts at the University of Texas, for instance, after controlling for confounding factors. Importantly, data also revealed that students within the PBCS cohort agreed more strongly that the case studies provided them with a better understanding of how scientific advancements and research impacted the community in which they lived than did their peers in the non-PBCS cohort. Collectively, these outcomes suggest that PBCSs offer a scalable, classroom-based approach to engage students in relevant, practical experiences that are of direct interest to them and, ideally, the broader scientific community

The Tigriopus CURE – A Course-Based Undergraduate Research Experience with Concomitant Supplemental Instruction

Evidence indicates that students who participate in scientific research during their undergraduate experience are more likely to pursue careers in the STEM disciplines and to develop increased scientific reasoning and literacy skills. One avenue to increase student engagement in research is via their enrollment in course-based undergraduate research experiences (CUREs), where they are able to conduct authentic research as part of the laboratory curriculum. The information presented herein provides an example of a CURE which was developed and implemented in an introductory cell and molecular biology course at the University of Northern Colorado. In addition to describing the Tigriopus CURE curriculum itself, we also present evidence regarding the effectiveness of the CURE in promoting students’ development of confidence in science process skills, quantitative reasoning skills, and written communication skills. The curricular details of the Tigriopus CURE are provided in this article to provide instructors who are interested in CUREs the opportunity to implement this specific CURE in their own course