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It is well-documented that the representation of women and racial/ethnic minorities diminishes at higher levels of academia, particularly in science, technology, engineering, and math (STEM). Sense of belonging-the extent to which an individual believes they are accepted, valued, and included in a community-is often emphasized as an important predictor of retention throughout academia. While literature addressing undergraduate sense of belonging is abundant, there has been little investigation of sense of belonging in graduate communities. Because graduate training is required to generate new scientific leaders, it is important to understand and address sense of belonging at the graduate level-paying explicit attention to devising strategies that can be used to increase representation at higher levels of academia. Here, a visual narrative survey and item response modeling are used to quantify sense of belonging among graduate students, postdoctoral researchers, and faculty within the Department of Chemistry at the University of California, Berkeley. Results suggest that graduate students, postdoctoral researchers, and faculty all experience impostor phenomenon. Respondents struggle most with maintaining positive self-perceptions of their productivity, capabilities as a scientist, and success-particularly in comparison to their peers. Communicating about science with peers, talking about teaching hurdles, and engaging in mentoring relationships also contribute significantly to sense of belonging. Faculty members have the highest sense of belonging, while senior graduate students and postdoctoral researchers are least likely to feel a sense of belonging. Additionally, graduate students and postdoctoral researchers who identify as underrepresented, as well as those who submit manuscripts for publication less than their peers, are less likely to feel a sense of belonging. This is the first study to generate a quantitative, nuanced understanding of sense of belonging within the entire graduate academic community of an R1 STEM department. We envision that these methods can be implemented within any research-focused academic unit to better understand the challenges facing community members and identify factors to address in promoting positive culture change. Furthermore, these methods and results should provide a foundation for devising interventions that academic stakeholders can use to directly improve graduate education., Competing Interests: The authors have declared that no competing interests exist.

Understanding the impact of undergraduate research experiences (UREs) and course-based undergraduate research experiences (CUREs) is crucial as universities debate the value of allocating scarce resources to these activities. We report on the Berkeley Undergraduate Research Evaluation Tools (BURET), designed to assess the learning outcomes of UREs and CUREs in chemistry and other sciences. To validate the tools, we administered BURET to 70 undergraduate students in the College of Chemistry and 19 students from other STEM fields, comparing the performance of students who had less than one year of undergraduate research to those with more than one year of research experience. Students wrote reflections and responded to interviews during poster presentations of their research project. BURET asks students to communicate the significance of their project, analyze their experimental design, interpret their data, and propose future research. Scoring rubrics reward students for integrating disciplinary evidence into their narratives. We found that the instruments yielded reliable scores, and the results clarified the impacts of undergraduate research, specifically characterizing the strengths and weaknesses of undergraduate researchers in chemistry at our institution. Students with at least a year of research experience were able to use disciplinary evidence more effectively than those with less than one year of experience. First-year students excelled at explaining the societal relevance of their work, but they incorporated only minimal discussion of prior research into their reflections and presentations. Students at all levels struggled to critique their own experimental design. These results have important implications for undergraduate learning, suggesting areas for faculty members, graduate student research mentors, and CURE or URE programs to improve undergraduate research experiences.

Peer learning programs have been developed to support many introductory science courses by providing additional instruction and engagement. These programs are beneficial to both learners and instructors, providing content learning and confidence and attitudinal gains. There is evidence that the benefits of peer learning are higher when students are taught by a near-peer instructor who is close to the learner in age and experience. Building on this existing evidence, a peer learning program, the Undergraduate Teacher-Scholar (UGTS) Program, was created, involving both graduate student and near-peer instructors teaching in the same discussion or laboratory section. This format creates a vertical learning community within the course structure. The Teacher-Scholar program provides the opportunity to compare the roles of graduate student and near-peer instructors teaching the same students the same instructional material. We report differences and similarities in the perceived roles of the graduate student and near-peer instructors by all of the stakeholders involved in the program. Both graduate student and near-peer instructors are valued by students; however, the near-peer instructors provide mentorship and role model qualities that are not replaced by a graduate student instructor.

Over the past several decades, green chemistry has gained prominence in chemistry education. However, the development of green chemistry curricula has not reached all levels of education equally, focusing mainly on elective and upper division courses. We deliberately focused our green chemistry curriculum redesign on a high enrollment introductory general chemistry laboratory course at the University of California, Berkeley. We developed over 30 new experiments that introduced students to green chemistry concepts and applications, while maintaining canonical general chemistry learning goals. The context of the curriculum and required course assignments encouraged students to use green chemistry principles to explore and solve real-world problems. After completing this redesigned course, we hypothesized that students would value green chemistry and feel more confident in their green chemistry knowledge. We developed new methods to measure students' attitudes toward and understanding of green chemistry as a system instead of isolated reactions or processes. These assessments allowed us to better understand both the progression and limitations in student green chemistry and systems-thinking. Since over 2000 students complete the laboratory course each year, we used a combination of fixed response items and free response items from online surveys and in-class assignments and exams. This approach allowed efficient assessment of thousands of students, while still gaining valuable and nuanced views of student understanding and attitudes. These assessments indicated that the new general chemistry laboratory curriculum succeeded in providing an environment in which students learned green chemistry concepts and realized that chemistry has connections to their future courses and professions.

The RNA recognition motif (RRM), one of the most common RNA binding domains, contains three highly conserved aromatic amino acids that participate in stacking interactions with RNA bases. The contribution of these highly conserved aromatic amino acids to the affinity of the complex formed between the N-terminal RRM of the U1A protein and stem loop of U1 snRNA is investigated.

Protein-RNA interactions were investigated in terms of mutation of a conserved aromatic residue.

Zirconocene azametallacyclobutene subjected to an insertion reaction with carbon monoxide forms an acyl complex. The reaction with aldehydes RCOH results in the addition of the aldehyde into the Zr-C bond to form complexes. The aldehyde insertion products form alpha,beta-unsaturated imines and (Cp2Zr=O) via a retro (4 + 2) reaction. The acetone addition results in an enolate complex formation due to deprotonation and no insertion occurs.

The bridging sulfido complex Cp2Zr(mu-N-t-Bu)(mu-S)IrCp* and the bridging oxo complex Cp2Zr(mu-N-t-Bu)(mu-O)IrCp* are obtained during the reactions between early-late heterobimetallic complex Cp2Zr(mu-N-t-Bu)IrCp* (1) and sulphur and oxygen atom donors respectively. The imido complex 1 is less selective towards sulfur atom donors because of the vigorous reaction rates of sulfur atom abstraction.

An early-late bridging imido complex, (CP2Zr(mu-N-t-Bu)IrCp*), Cp* = C5Me5, is synthesized. This complex exhibits cooperative reactivity with organic substances having X-H bonds and is more reactive due to a reactive metal-metal bond, unsaturated metal centers and unreactive imido ligand link. The complex with phosphine yields complexes with Ir-P bond through unusual phosphide insertion and forms Zr-N and Zr-O bonds with acetone para-cresol and para-toluidine.

The catalytic hydroamination of unsymmetrical alkynes and the regioselectivity of the catalytic process were investigated. Results showed that the regioselectivity of stoichiometric hydroamination is high for both aryl- and alkylacetylenes. The catalytic reaction proceeded via kinetics that were consistent with the general rate law. A study of reaction rates revealed that unimolecular reaction increases rapidly with temperature. The selectivity of the catalytic cycle was under kinetic control.

The synthesis of enamines and imines from the hydroamination of alkynes and allene catalyzed by Cp2Zr(NHR)2 was reported. A first-order reaction with respect to the bisamide and alkyne and an inverse first order in amine were deduced from examination of the reaction of 2,6-dimethylaniline and diphenylacetylene in the presence of the zirconium bisamide. A mechanism based from kinetic and stoichiometric results proposed the intermediacy of Cp2Zr=NR complex, azametallacyclobutenes and an enamide amide.

The analysis of correlated inter-residue fluctuations within the complex formed between U1A and stem loop 2 of U1 snRNA based on molecular dynamics (MD) simulations is reported. The collective atomic fluctuations are found to be indicative of cooperative effects and thermodynamic coupling and this approach can be adapted to the study of cooperatively in protein-DNA, protein-protein or any system on which MD can be performed successfully.

The way in which RNA conformation contributes to the stability of a high-affinity RNA-protein complex is demonstrated.

The RNA complex of a 101 amino acid peptide composed of the N-terminal RNP domain of the protein U1A, called U1A101, was investigated. The N-terminal RNP domain of U1A contains two highly conserved aromatic amino acids, Phe56 and Tyr13, and both are observed to participate in stacking interactions with RNA bases in structures obtained by X-ray crystallography and NMR spectroscopy. It was observed that replacing one aromatic functional group of a protein with hydrogen can have an energetic effect on an RNA-protein complex stability of 5.5 kcal/mol.

Reaction of early-late heterobinuclear complex with carbon dioxide generates metal-metal insertion products. Treatment of Cp2Zr(mu-N(super t)Bu)IrCp* (1) (Cp* = pentamethylcyclopentadienyl) with CO2 produces a heterobimetallacyclic complex by addition of CO2 C-O double bond across the Zr-Ir bond. Exposure of CO2 to ELHB dihydride generates a heterobimetallic formato complex, which is changed stoichiometrically to formic acid. X-ray diffraction analysis indicate that of the two C-O bonds, one is a single bond and one is double.

The investigation of the synthesis of alpha,beta-unsaturated imines reveals that thermal decomposition of azaoxametallacycles occurs through the process of retrocycloaddition. The retrocycloaddition process is identical to that of the organic retro-Diels-Alder reactions which results in formation of monomeric Cp2Zr-O. The investigation is performed by the trapping of oxozirconocene in a (4+)azaoxametallacyclohexane retrocycloaddition.

The first illustration of an early-late heterobimetallic imido complex was used in the synthesis of Cp2Zr(mu-N-t-Bu)IrCp* (1). The reactivity of this complex was compared with X-H bonds having hard and soft heteroatoms. X-H bonds were added across the metal-metal bond, when treated with p-thiocresol, p-cresol, 1, 1-dimethylethanol and P-toluidine. A bridging aminophosphine complex resulted from an extraordinary phosphide insertion caused by the treatment of 1 with phosphines.