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Scholarly Communication Work: On the Ground Perspectives
Get PDFThis survey investigates the experiences of scholarly communication workers in North America, with a total of 282 responses. Previous studies on scholarly communication work in academic libraries have tended to focus on organizational structure and necessary competencies. This study aims to put the focus back on workers’ own experiences on the job, to better understand the contributing factors to burnout and attrition that can arise for those in these positions. Five main areas are investigated: newness of the position, scope of the work, support and resources, feelings of one’s expertise being unvalued or dismissed, and the impact of administration. The study concludes with recommendations for library administrators on how to fortify a more sustainable environment for scholarly communication worker
Design of isolated buildings to achieve targeted collapse limits through Gaussian process modeling
Get PDFContribución de Trifonio Delgado Gonzales a la Historia del Espacio Urbano de Oruro [Bolivia]. Problemas de Vivienda e Inquilinato. 1951-1952,
Get PDFBased on an inform written by labor historian Trifonio Delgado Gonzales, this contribution studies the 1940s-1950s Oruro (Bolivia) urban space development and growth. Editor Guillermo Delgado-P. offers an urban anthropological introduction to the document contextualing it within Latin American urban and population growth at the time
The Villages at 995 East Santa Clara St, San Jose: Energy & Emission Report
Get PDFOur study uses EnergyPlus simulations to examine whole-building demand and energy end-use profiles for different design options and then uses these outputs to evaluate cost and carbon impacts of each scenario in Xendee, a modeling platform designed to “right size” and balance investments in distributed energy resources (DER). Our results show that efficiency measures are key to meet the ambitious performance metrics for this project; however, most of the technology potential occurs for heating, ventilation and air conditioning (HVAC) or domestic hot water (DHW) loads which are a relatively small portion of a mid-rise multifamily building’s overall energy use. The most meaningful strategies to reduce or shift loads for this building include DHW load shifting, energy recovery ventilation, dynamic ventilation, and ceiling fans. Envelope strategies improve overall annual building performance but become an issue when lower heat loss increases cooling during the critical afternoon peak. Compared to efficient, packaged air source heat pumps, a hydronic heating and cooling system (also serving DHW loads) with thermal energy storage has the best energy performance, highest load shifting capability, and best thermal resilience during outages. But because heating and cooling demands are small and hydronic systems are expensive, the net benefits of thermal energy storage are not substantial. Sizing on-site generation and storage systems to cover the “worst case” outage conditions significantly drives up system size and cost. Even small deviations from 100% coverage (95%, or 99%) can dramatically reduce size and cost without a very meaningful change in resilience
Industrial Process Fault Detection Based on Siamese Recurrent Autoencoder
Get PDFAlthough deep autoencoders excel at extracting intricate features, their application in process monitoring is limited by the requirement for large sample sizes and interpretability of latent representations. This work presents a special deep learning structure named Siamese network to detect abnormal deviations in nonlinear dynamic processes. By leveraging the capability of Siamese architecture to process multiple inputs simultaneously, the training sample size expands exponentially, which enhances the learning potential of the model. Furthermore, a long short-term memory unit is integrated to enable the capture of long-term process dynamics. To refine the distribution of latent features extracted from diverse data types, a contrastive loss function is proposed, which strengthens the model's fault detection capabilities and enhances its interpretation of latent representations. Then T2 statistic is established on the latent space to perform fault detection. The effectiveness of the method is demonstrated through case studies on simulation processes and an industrial process
Phylogenomic insights into the taxonomy, ecology, and mating systems of the lorchel family Discinaceae (Pezizales, Ascomycota)
Get PDFLorchels, also known as false morels (Gyromitra sensu lato), are iconic due to their brain-shaped mushrooms and production of gyromitrin, a deadly mycotoxin. Molecular phylogenetic studies have hitherto failed to resolve deep-branching relationships in the lorchel family, Discinaceae, hampering our ability to settle longstanding taxonomic debates and to reconstruct the evolution of toxin production. We generated 75 draft genomes from cultures and ascomata (some collected as early as 1960), conducted phylogenomic analyses using 1542 single-copy orthologs to infer the early evolutionary history of lorchels, and identified genomic signatures of trophic mode and mating-type loci to better understand lorchel ecology and reproductive biology. Our phylogenomic tree was supported by high gene tree concordance, facilitating taxonomic revisions in Discinaceae. We recognized 10 genera across two tribes: tribe Discineae (Discina, Maublancomyces, Neogyromitra, Piscidiscina, and Pseudodiscina) and tribe Gyromitreae (Gyromitra, Hydnotrya, Paragyromitra, Pseudorhizina, and Pseudoverpa); Piscidiscina was newly erected and 26 new combinations were formalized. Paradiscina melaleuca and Marcelleina donadinii formed their own family-level clade sister to Morchellaceae, which merits further taxonomic study. Genome size and CAZyme content were consistent with a mycorrhizal lifestyle for the truffle species (Hydnotrya spp.), whereas the other Discinaceae genera possessed genomic properties of a saprotrophic habit. Lorchels were found to be predominantly heterothallic-either MAT1-1 or MAT1-2-but a single occurrence of colocalized mating-type idiomorphs indicative of homothallism was observed in Gyromitra esculenta strain CBS101906 and requires additional confirmation and follow-up study. Lastly, we confirmed that gyromitrin has a phylogenetically discontinuous distribution, having been detected exclusively in two distantly related genera (Gyromitra and Piscidiscina) belonging to separate tribes. Our genomic dataset will facilitate further investigations into the gyromitrin biosynthesis genes and their evolutionary history. With additional sampling of Geomoriaceae and Helvellaceae-two closely related families with no publicly available genomes-these data will enable comprehensive studies on the independent evolution of truffles and ecological diversification in an economically important group of pezizalean fungi
A Foundational Shift in Models for Enzyme Function
No full textThis Perspective addresses the unresolved, and still hotly contested, question of how enzymes transition from stable enzyme-substrate (ES) complexes to successful, femtosecond barrier crossings. By extending Marcus theory to enzyme-catalyzed reactions, we argue that environmental reorganization of the protein scaffold, together with associated water molecules, achieves the intersection of reactant and product potential energy surfaces. After discussing the experimentally demonstrated importance of reduced activation enthalpy in enzyme-catalyzed transformations, we describe new methodologies that measure the temperature dependence of (i) time-averaged hydrogen/deuterium exchange into backbone amides and (ii) time-dependent Stokes shifts to longer emission wavelengths in appended chromophores at the protein/water interface. These methods not only identify specific pathways for the transfer of thermal energy from solvent to the reacting bonds of bound substrates but also suggest that collective thermally activated protein restructuring must occur very rapidly (on the ns-ps time scale) over long distances. Based on these findings, we introduce a comprehensive model for how barrier crossing takes place from the ES complex. This exploits the structural preorganization inherent in protein folding and subsequent conformational sampling, which optimally positions essential catalytic components within ES ground states and correctly places reactive bonds in the substrate(s) relative to embedded energy transfer networks connecting the protein surface to the active site. The existence of these anisotropic energy distribution pathways introduces a new dimension into the ongoing quest for improved de novo enzyme design
Acute Cardiogenic Shock Secondary to Left Main Occlusion in a Patient with Behçet Disease
Get PDFCoronary artery involvement in Behçet disease (BD) is exceedingly rare and is associated with significant risk of short-term and long-term mortality. We describe a rare case of ST-segment elevation myocardial infarction and cardiogenic shock due to suspected coronary vasculitis in a patient with BD successfully treated with mechanical circulatory support
Affordances of Immersive Study Abroad for Writing and Plurilingual-Pluricultural Competence Development
Get PDFThis dissertation addresses calls for greater research on (1) writing development during language immersive study abroad (SA; Vallejos & Sanz, 2021), (2) the experiences of heritage language learners in SA (Pozzi et al., 2021), and (3) the evolution and changes in SA programming post-COVID (Blake & Morris, 2023). Organized as three articles driven by qualitative inquiry and case study methodology, this dissertation offers novel insight into the present, past, and future of SA. I analyze data from two Spanish-immersive study abroad programs in Madrid, Spain, and Mendoza, Argentina that ran for decades out of a large, public university in California, U.S. As this university serves a large number of Latinx students–these students constituted approximately 25% of the university population in 2024–in a region characterized by a strong presence of Spanish-English bilingualism, many students who studied abroad through the focal SA programs were Spanish heritage language learners (SHLLs). Charting these students’ experiences and what they take away from SA can offer insight to SA program leaders about how to tailor their programs and practices to best serve this population, whose participation is growing in SA (Pozzi et al., 2021).
The first article of this dissertation investigates how the features of the two programs supported plurilingual-pluricultural competence (PPC) development, and how the future plans for the programs may or may not support PPC. PPC describes students’ abilities to communicate in multiple languages and to interact in multiple cultures (Coste et al., 2009). I collected information about the program features through interviews with students and program leaders, notes from the pre-departure orientations, and secondary sources about the programs. I analyzed the data according to three temporal axes: past, present (2022-2023), and future. Considering the past and present iterations of the programs, the features that most clearly supported PPC growth were those that fostered (1) plurilingual-pluricultural socialization through interaction with local community members and (2) critical self-reflection on these interactions. Both programs were impacted by the COVID-19 pandemic and related financial constraints, which contributed to the cancellation of both programs in 2024. The ways in which the program leaders discussed the future of SA illustrate neoliberal and monolingual ideologies that position education as a business and English as a dominant global language, deemphasizing the importance of PPC as an outcome of SA. The article offers implications for SA program design, considering the many stakeholders involved in SA and the financial constraints inherent in the current state of higher education.
Articles two and three focus on the Madrid program, from which I collected ethnographic data as a participant observer in spring of 2023. The second article describes the writing pedagogies employed by the Madrid program instructors and program stakeholders’ evaluations of the effectiveness of these pedagogies, in light of students’ self-reported areas for improvement. This case study draws from analysis of pre- and post-program interviews with students and post-program interviews with instructors, field notes, and program artifacts including course syllabi, assignment sheets, and instructional materials. Students and instructors found the following curricular approaches to be effective for writing development abroad: (1) frequent writing; (2) process-based, meaningful composition assignments that include low-stakes writing components; (3) portfolio assessment; (4) writing by hand; and (5) timely instructor written corrective feedback. SHLLs particularly valued writing by hand as a way to address their perceived need for improvement in orthographic accuracy. I conclude by discussing the potential of meaningful writing assignments for curricular developments in SA writing pedagogy.
The final article considers SHLL writing development abroad and argues for the importance of methodological multiplicity when analyzing student writing from this context. I contend that more SA research ought to conceptualize writing as a social practice and act of identity, which necessitates expanding the methods used to analyze SA writing beyond only measuring complexity, accuracy, and fluency. Through a case study of Alejandro, a U.S. student with roots in Jalisco, Mexico studying in Madrid, I illustrate how compositions can showcase students’ engagement in identity work and agency development during their sojourn. I analyze the emails that Alejandro wrote to a hypothetical peer and professor audience at the beginning, middle, and end of the program, evaluations of these emails from trained raters, complexity measures of these emails, as well as pre- and post-program interviews with Alejandro, an end-of-study focus group, and field notes about my interactions with Alejandro. By triangulating all of these data sources, this study offers a more complete picture of what Alejandro demonstrates through his compositions abroad: increases in sociolinguistic awareness, pride in his jalisciense identity, and agency, as well as growth in the rhetorical effectiveness, concision, lexical diversity, and register and genre adequacy of his emails. The article concludes with a call for more human-centered SA writing research, especially when working with historically marginalized populations like SHLLs
Deciphering the Role of Dietary Fat Quantity and Composition in Pancreatic Carcinogenesis
No full textConsidering the lethal nature of pancreatic ductal adenocarcinoma and paucity of effective treatments, the development of safe and efficacious prevention strategies are of paramount importance. Diet is emerging as a major modifiable risk factor for the development of many diseases including pancreatic cancer. In particular, a macronutrient that has been correlated with pancreatic cancer development is dietary fat. Additionally, abdominal fat is considered a causal factor in pancreatic cancer development. High total dietary fat consumption, especially the types of fats common in the industrialized diet such as saturated fat, has been linked with the development of both obesity and pancreatic cancer. Overall, the effects of high and low-fat diets containing different types of lipids, such as anti-inflammatory omega-3 polyunsaturated fatty acids (PUFA), are less well understood in pancreatic carcinogenesis. Additionally, while studies demonstrate the acceleration of pancreatic carcinogenesis with a diet high in total fat, with high amounts of saturated or omega-6 PUFA, it remains unknown how changing a carcinogenesis-accelerating diet could affect pancreatic cancer development. This dissertation aims to understand and evaluate the role of dietary fat quantity and composition in pancreatic carcinogenesis in a mouse model (KC P48+/Cre;LSL-KRASG12D) that recapitulates the development of pancreatic cancer. The first chapter of this dissertation is a review paper summarizing the relevant epidemiological and mechanistic research exploring the connection between dietary fat quantity and composition and pancreatic cancer. In humans, an important prospective cohort study in the US suggests that high intakes of total fat, saturated fat, and monounsaturated fat from meat and dairy increase the risk of pancreatic cancer. In contrast, a prospective cohort study in the Netherlands found no relationship between pancreatic cancer and total fat, saturated fat, or monounsaturated fat intake. Interestingly, intake of linolenic acid (18:2, n-6) has been correlated with a decreased risk of pancreatic cancer in several human studies which is counter to the findings from animal studies. As for marine-sourced, long-chain, highly unsaturated omega-3 fatty acids, such as eicosapentaenoic acid (20:5, n-3) and docosahexaenoic acid (22:6, n-3), a study from Japan suggested a protective effect, while a different meta-analysis found no effect. These incongruent findings in humans are also reflected in other meta-analyses with one published article reporting no correlation between dietary fat and pancreatic cancer and another article reporting that high saturated fat diets were associated with the highest relative risk of developing pancreatic cancer. The limitations of these types of research include the subjective assessment of dietary intake and inherent recall bias of food frequency questionnaires. Future research would be improved by utilizing objective biomarkers of dietary intake, including diverse populations, and considering genetic differences in fatty acid metabolism. Preclinical findings are more consistent, with the majority of papers suggesting a causal link between high (60% kcal from fat and 40-45% kcal from fat) lard and corn oil consumption and acceleration of pancreatic carcinogenesis in genetically engineered mouse models or the aggravation of implanted tumors. Additionally, murine feeding studies with diets rich in fish oil suggest a protective effect against pancreatic cancer development. Animal models are useful for better understanding the cellular mechanisms linking dietary fat and pancreatic cancer development, however, details about the composition of the diets are crucial when drawing conclusions about the findings and were not always complete. Overall, the current evidence suggests that diets lower in fat and higher in ω-3 PUFA may be beneficial in reducing the overall risk of pancreatic cancer. With this information, I hypothesized that diets low in total dietary fat and high in ω-3 PUFA to be beneficial for pancreatic cancer prevention, especially when compared to diets that are high in total dietary fat or have lower ω-3 PUFA composition.In Aim 1, I determined the role of dietary fat quantity and composition in the early stages of pancreatic cancer progression. To this end, male (n = 9-11) and female (n = 9-13) KC mice were fed one of four diets (1) a Low-Fat, Low Omega-3 PUFA diet with 11% kcal from fat and a ~10:1 ratio of ω-6 to ω-3 PUFA (LFLO), (2) a High-Fat, Low Omega-3 PUFA diet with 60% kcal from fat and a ~10:1 ratio of ω-6 to ω-3 PUFA (HFLO), (3) a Low-Fat, High Omega-3 PUFA diet with 11% kcal from fat and a ~1:1 ratio of ω-6 to ω-3 PUFA (LFHO), a High-Fat, High Omega-3 PUFA diet with 60% kcal from fat and a ~1:1 ratio of ω-6 to ω-3 PUFA (HFHO) for 8 weeks until 3 months of age. Body weight, body fat, and calorie intake was higher in the HFLO fed mice. In the pancreas, HFLO diet feeding increased pancreas weight, acinar-to-ductal metaplasia (ADM), fibrosis, and proliferation, especially in female mice. The levels of COX-2, phosphorylated ERK1/2 and phosphorylated STAT3 were elevated by the HFLO diet in female mice. Overall, diets low in fat and diets high in ω-3 PUFA appear to be beneficial in slowing the early pancreatic precancerous changes associated with feeding a HFLO diet.In Aim 2, I set out to determine the role of changes in dietary fat quantity and composition in pancreatic cancer progression. To evaluate this, I used the same four diets in Aim 1 with 8-10 male and 9-12 female KC mice enrolled into each of the five dietary treatment groups. The LFLO and HFLO diets were fed until 6 months of age in the two continuous feeding groups. In the three dietary switch groups, mice started on the HFLO diet until 3 months of age and then switched to one of the other three diets (LFLO, LFHO, or HFHO) until 6 months of age. The continuously fed HFLO mice had higher calorie intake and increased body weight, body fat, and pancreas weight compared to the other diet groups. Two male mice out of 21 total mice in the HFLO group and 2 female mice out of 22 total mice in the HFLO -> HFHO group developed pancreatic cancer. HFLO feeding led to increased ADM and fibrosis in the pancreas. Mechanistically, the phosphorylation levels of ERK1/2 and STAT3 were increased as a result of HFLO feeding and normalized to LFLO/control levels in the dietary switch groups. The gastrointestinal microbiome composition was differentially affected at the phylum and genus level in the five dietary treatment groups. At the phylum level, the mice in the three dietary switch groups had an increase in the relative abundance of Bacteroidota and a decrease in Firmicutes, compared to the continuously fed mice. Among others, one genus of microbes in the Bacteroidota phylum that has been associated with human health, Muribaculaceae, was reduced by high-fat feeding and the relative abundance of this group of bacteria was restored by the dietary switch. Overall, these findings suggest that lowering overall dietary fat intake and/or changing dietary fat composition may favorably influence pancreatic carcinogenesis. Aim 3 evaluated some of the key mechanisms by which obesity influences pancreatic cancer progression. To this end, I isolated RNA from the pancreas of mice in the LFLO (LF), HFLO (HF), and switch from HF to LF dietary treatment groups from Aim 2. Using RNA sequencing and Gene Set Enrichment Analysis (GSEA), I found that the HF diet was positively correlated with enrichment in the TNF signaling via NF-κB pathway and the IL6-JAK-STAT3 signaling pathway. In both GSEA and bioinformatics analysis, the gene expression profile of the LF and HF -> LF fed mice was more similar compared to the HF fed mice. Furthermore, compared to the LF diet, the HF diet altered the gut microbiome composition, increasing the relative abundance of: (class) Firmicutes clostridia, (genus) Lachnospiraceae Blautia and Roseburia, as well as Oscillospiraceae Oscillibacter, Intestimonas, and Colidextribacter. The dietary switch restored the relative abundance of these microbes to be similar to the LF group. Overall, switching from a high to a low-fat diet appeared to be effective at favorably altering pancreatic gene expression profiles and the relative abundance of several gastrointestinal microbes linked to health, which elucidates some of the key mechanisms by which preventing obesity by lowering dietary fat intake may be beneficial in the context of pancreatic cancer prevention.In summary, the research conducted in this dissertation suggests that changing dietary fat quantity from high to low and the inclusion of dietary ω-3 PUFA may one day prove to be a safe and noninvasive approach to pancreatic cancer prevention; especially in individuals with elevated body fatness who are at a higher risk of pancreatic cancer. Low-fat and/or high ω-3 PUFA diets slowed ADM and fibrosis and led to favorable alterations in the ERK1/2 and STAT3 pathways and gastrointestinal microbiota composition. Additionally, a number of changes in global gene expression in the HF-> LF dietary switch group were noted which may explain the potential for changes in dietary fat quantity to possibly mitigate pancreatic carcinogenesis in the early stages. Overall, these findings linking dietary fat and pancreatic carcinogenesis are preliminary and the role of diet and dietary changes in pancreatic cancer prevention warrants further investigation