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Methane Fluxes in Tidal Marshes of the Conterminous United States
Get PDFMethane (CH4) is a potent greenhouse gas (GHG) with atmospheric concentrations that have nearly tripled since pre-industrial times. Wetlands account for a large share of global CH4 emissions, yet the magnitude and factors controlling CH4 fluxes in tidal wetlands remain uncertain. We synthesized CH4 flux data from 100 chamber and 9 eddy covariance (EC) sites across tidal marshes in the conterminous United States to assess controlling factors and improve predictions of CH4 emissions. This effort included creating an open-source database of chamber-based GHG fluxes (https://doi.org/10.25573/serc.14227085). Annual fluxes across chamber and EC sites averaged 26 ± 53 g CH4 m−2 year−1, with a median of 3.9 g CH4 m−2 year−1, and only 25% of sites exceeding 18 g CH4 m−2 year−1. The highest fluxes were observed at fresh-oligohaline sites with daily maximum temperature normals (MATmax) above 25.6°C. These were followed by frequently inundated low and mid-fresh-oligohaline marshes with MATmax ≤25.6°C, and mesohaline sites with MATmax \u3e19°C. Quantile regressions of paired chamber CH4 flux and porewater biogeochemistry revealed that the 90th percentile of fluxes fell below 5 ± 3 nmol m−2 s−1 at sulfate concentrations \u3e4.7 ± 0.6 mM, porewater salinity \u3e21 ± 2 psu, or surface water salinity \u3e15 ± 3 psu. Across sites, salinity was the dominant predictor of annual CH4 fluxes, while within sites, temperature, gross primary productivity (GPP), and tidal height controlled variability at diel and seasonal scales. At the diel scale, GPP preceded temperature in importance for predicting CH4 flux changes, while the opposite was observed at the seasonal scale. Water levels influenced the timing and pathway of diel CH4 fluxes, with pulsed releases of stored CH4 at low to rising tide. This study provides data and methods to improve tidal marsh CH4 emission estimates, support blue carbon assessments, and refine national and global GHG inventories
AlphaFold2 Modeling and Molecular Dynamics Simulations of the Conformational Ensembles for the SARS-CoV-2 Spike Omicron JN.1, KP.2 and KP.3 Variants: Mutational Profiling of Binding Energetics Reveals Epistatic Drivers of the ACE2 Affinity and Escape Hotspots of Antibody Resistance
Get PDFAlphaFold2-based atomistic predictions of structures and conformational ensembles of the SARS-CoV-2 spike complexes with the host receptor ACE2 for the most dominant Omicron variants JN.1, KP.1, KP.2 and KP.3 to examine the mechanisms underlying the role of convergent evolution hotspots in balancing ACE2 binding and antibody evasion. Using the ensemble-based mutational scanning of the spike protein residues and computations of binding affinities, we identified binding energy hotspots and characterized the molecular basis underlying epistatic couplings between convergent mutational hotspots. The results suggested the existence of epistatic interactions between convergent mutational sites at L455, F456, Q493 positions that protect and restore ACE2-binding affinity while conferring beneficial immune escape. To examine immune escape mechanisms, we performed structure-based mutational profiling of the spike protein binding with several classes of antibodies that displayed impaired neutralization against BA.2.86, JN.1, KP.2 and KP.3. The results confirmed the experimental data that JN.1, KP.2 and KP.3 harboring the L455S and F456L mutations can significantly impair the neutralizing activity of class 1 monoclonal antibodies, while the epistatic effects mediated by F456L can facilitate the subsequent convergence of Q493E changes to rescue ACE2 binding. Structural and energetic analysis provided a rationale to the experimental results showing that BD55-5840 and BD55-5514 antibodies that bind to different binding epitopes can retain neutralizing efficacy against all examined variants BA.2.86, JN.1, KP.2 and KP.3. The results support the notion that evolution of Omicron variants may favor emergence of lineages with beneficial combinations of mutations involving mediators of epistatic couplings that control balance of high ACE2 affinity and immune evasion
Text and Data Mining for Pianists? Bringing Digital Humanities to a Graduate Music Research Methods Course Through Topic Modeling
Get PDFThis article provides an example of the successful integration of text and data mining (TDM) into the Research Methods for Performers course, a required course for students in the Keyboard Collaborative Arts (KCA) Master of Music (MM) program at Chapman University. This course is similar in scope and content to the course frequently titled Music Bibliography at other institutions, and the methods described also apply to such courses. Incorporating TDM into this course effectively introduced data-focused research methods to performing arts students and expanded the students’ understanding of the scope and possibilities of research in music through the application of digital humanities in the study of music.
This case study will present the author’s perspective as an instructor with a music librarianship background, not from the position of an experienced data scientist. The focus is primarily pedagogical and concerns teaching students from a music background, so it does not contain highly technical concepts, programming information, or detailed data analysis. Although this case study is from an instructor’s perspective, the methods are also relevant to librarians seeking a pathway to enhance their library instruction and research assistance skill set
How Personalized Networks Can Limit Free Riding: A Multi-Group Version of the Public Goods Game
Get PDFPeople belong to many different groups, and few belong to the same network of groups. Moreover, people routinely reduce their involvement in dysfunctional groups while increasing involvement in those they find more attractive. The net effect can be an increase in overall cooperation and the partial isolation of free-riders, even if free-riders are never punished, excluded, or recognized. We formalize and test this conjecture with an agent-based social simulation and a multi-good extension of the standard repeated public goods game. Our initial results from three treatments suggest that the multi-group setting indeed raises overall cooperation and dampens the impact of freeriders. We extend our understanding of this setting by imposing greater heterogeneity between groups through interweaving automated bot players amongst human subjects; whereby initial sessions of this amplify the aforementioned effects
Aligning Eye Care Provider Beliefs with Behaviors: Exploring and Improving Ocular Surface Disease Decision-making in a Cataract Surgery Clinic
No full textMillions of cataract surgeries are performed every year in the United States, yet both surgeon reports and patient reports indicate that practices are not utilizing the diagnostic tests and treatments that are advocated in the medical literature to identify and manage ocular surface disease prior to surgery. As a result, patients risk suffering several significant consequences with regard to their vision, comfort and safety. Personal observations from my 25 years of experience working with ophthalmologists and optometrists led to curiosity regarding the root cause of undertreatment of ocular surface disease. Specifically, I had the impression that eye care providers held strongly to the belief that ocular surface disease should be managed preoperatively, yet this belief was not reflected in their behavior. The overall aim of this dissertation is to ascertain the validity of my unscientific observations and to provide a customized tool that can be used in a single cataract surgery clinic to increase goal-congruent behavior among eye care providers. Phase One involved interviews with 42 ophthalmologists and optometrists on preoperative ocular surface disease management in cataract surgery patients. Using the Health Belief Model (Rosenstock, 1966) as a guide, these results helped characterize the misalignment between beliefs and behaviors while establishing the ethical imperative to proceed in the direction of intervention development. Phase Two was a rigorous case study of a high-volume cataract surgery care center. This included observations, a review of artifacts, and interviews with seven doctors, three staff members and five patients. Using Nudge Theory (Thaler & Sunstein, 2008) as a guide, these results elucidated decision-making processes and elements of the practice’s choice architecture that either limit or support preoperative ocular surface disease management in cataract surgery patients. Finally, Phase Three presents theory-driven recommendations in the form of a practical and easy-to-read intervention guide. Six action items are presented as strategies to help the doctors and staff overcome the specific challenges that lead to the undertreatment of ocular surface disease
Using the LMS Effectively to Reduce Logistical Challenges for Students
No full textWhen preparing for a new term, there is much to consider. Textbooks and course materials to review, syllabi to update, lessons to plan, lectures to prepare. Since the pandemic, which necessitated the use of Learning Management Systems (LMS) such as Canvas or Blackboard, there is now an additional component to consider in developing our courses. Instead of thinking about the LMS as simply a repository for course essentials (syllabus, contact information, etc.), consider how it might be used as a tool for enhancing student learning and engagement
Soil Moisture-Derived SWDI at 30 m Based on Multiple Satellite Datasets for Agricultural Drought Monitoring
Get PDFAs a major agricultural hazard, drought frequently occurs due to a reduction in precipitation resulting in a continuously propagating soil moisture (SM) deficit. Assessment of the high spatial-resolution SM-derived drought index is crucial for monitoring agricultural drought. In this study, we generated a downscaled random forest SM dataset (RF-SM) and calculated the soil water deficit index (RF-SM-SWDI) at 30 m for agricultural drought monitoring. The results showed that the RF-SM dataset exhibited better consistency with in situ SM observations in the detection of extremes than did the SM products, including SMAP, SMOS, NCA-LDAS, and ESA CCI, for different land cover types in the U.S. and yielded a satisfactory performance, with the lowest root mean square error (RMSE, below 0.055 m3/m3) and the highest coefficient of determination (R2, above 0.8) for most observation networks, based on the number of sites. A vegetation health index (VHI), derived from a Landsat 8 optical remote sensing dataset, was also generated for comparison. The results illustrated that the RF-SM-SWDI and VHI exhibited high correlations (R ≥ 0.5) at approximately 70% of the stations. Furthermore, we mapped spatiotemporal drought monitoring indices in California. The RF-SM-SWDI provided drought conditions with more detailed spatial information than did the short-term drought blend (STDB) released by the U.S. Drought Monitor, which demonstrated the expected response of seasonal drought trends, while differences from the VHI were observed mainly in forest areas. Therefore, downscaled SM and SWDI, with a spatial resolution of 30 m, are promising for monitoring agricultural field drought within different contexts, and additional reliable factors could be incorporated to better guide agricultural management practices
Carrying Meaning, Bridging Worlds: Indigenous Language Localization in Western Courts
Get PDFThis work examines the localization practices of Indigenous court interpreters through prototyping and analyzing legal glossaries in eight Indigenous languages from the State of Oaxaca, Mexico. These languages are often needed in Mexican courts and immigration court hearings in the United States. Thus, examining the localization praxes of the court interpreters who use them can provide important intercultural technical and professional communication insights in global contexts. I compare the preliminary results of this ongoing study with the court interpreters\u27 code of ethics from the State of California to demonstrate how Western court assumptions about language interpretation cause gaps between worldviews. This work also shows how court expectations do not always reflect the localization practices of Indigenous court interpreters
Intersectional Marxism and the Dialectic: Interpreting Marx for Our Times
Get PDFMany on the radical left are increasingly seeking a humanist alternative to the white supremacist capitalist patriarchy that has produced immeasurable suffering and destruction. Amidst the fascism ignited within this era’s supra-conservatism, many of us turned to the Democratic Party to ensure Trump’s defeat only to be reminded that both major political parties in the United States have always moved to the tune of capitalist interests.1 Thus, at this time, especially, we must remain hopeful in order to continue our struggle to develop a viable alternative to the current system.
This new PM Press edition of Karl Marx’s Critique of the Gotha Program offers such a vision and with it the hope for change that we crave
Shanghai AroMap
No full textShanghai AroMap is a memoir about bringing up Chinese/Scottish children in present day Shanghai. The framework for this memoir is a sensory exploration of the city and its history, primarily through olfaction