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This paper introduces the Watermark Imaging System (WImSy) which can be used to photograph, document, and study sheets of paper. The WImSy provides surface images, raking light images, and transmitted light images of the paper, all in perfect alignment. We develop algorithms that exploit this alignment by combining several images together in a process that mimics both the "surface image removal" technique and the method of "high dynamic range" photographs. An improved optimization criterion and an automatic parameter selection procedure streamline the process and make it practical for art historians and conservators to extract the relevant information to study watermarks. The effectiveness of the method is demonstrated in several experiments on images taken with the WImSy at the Metropolitan Museum of Art in New York and at the Getty Museum in Los Angeles, and the results are compared with manually optimized images. [ABSTRACT FROM AUTHOR]

This paper focuses on crime status prediction through an ensemble methodology applied to extensive datasets obtained from catalog.data.gov, specifically targeting Los Angeles crime incidents since 2020. The research methodology comprises meticulous data collection, rigorous preprocessing, exploratory data analysis, model selection, and comprehensive model evaluation. Initial challenges included data inaccuracies and privacy-preserving measures in location data, necessitating thorough cleaning and transformation processes. Exploratory data analysis revealed crucial insights, including the 'Status' attribute's limited correlation, crime code distributions, areawise crime counts, and temporal patterns. To address class imbalance within 'Status', the Synthetic Minority Oversampling Technique (SMOTE) was applied to balance the dataset. Model evaluation highlighted the superiority of random forest models employing 10 and 20 decision trees, alongside KNN, which demonstrated consistent high accuracy, balanced precision-recall trade-offs, and notable F1 scores in crime status prediction. [ABSTRACT FROM AUTHOR]

Runtime verification (RV) refers to methods for formal reasoning about all aspects of the dynamic execution of systems, including hardware, software, and cyber-physical systems. RV includes techniques to assess and enforce correctness of a system against systemic bugs or extrinsic uncertainties. These methods are typically considered lightweight as they may not involve exhaustive verification or proofs, but they provide a higher level of rigor and versatility compared to conventional testing methods. This article introduces the extended versions of selected papers from the peer-reviewed proceedings of the 20th International Conference on Runtime Verification (RV 2020). RV 2020 was supposed to be held in Los Angeles, California, USA in July 2020, but was instead held virtually due to the global Covid-19 pandemic. [ABSTRACT FROM AUTHOR]

The article focuses on Paper trash from Los Angeles (LA) City Hall and two LA office buildings that may soon be on its way to China. The paper is being analyzed for its export value, and, sometime this summer, China Paper Partners of San Francisco, an affiliate of the Conservatree Paper Co., plans to begin shipping the paper trash to the People's Republic of China, where it will be sorted and recycled. Instead of going into already overburdened landfills on this side of the Pacific, as much as 1,000 tons of paper trash per day may make the voyage to China, where paper material is in great demand.

The winner of the 2020 TPS Best Paper Award has been selected (please refer to our TPS home page for details about the award at https://ieee-npss.org/publications/transactions-on-plasma-science/). This year is the second year that the award is being given, and I am pleased to announce that Prof. Chandrashekhar Joshi, Department of Electrical and Computer Engineering, University of California at Los Angeles, Los Angeles, CA, USA, is the winner for his article “Laser-driven plasma accelerators operating in the self- guided, blowout regime.” This article appeared in IEEE TPS, vol. 45, pp. 3134–3146, in December 2017. The award plaque, certificate, and cheque will be presented to Prof. Joshi at an upcoming International Conference on Plasma Science in South Lake Tahoe, CA, USA, in June 2021. This is an open-access article and is freely available to our readers. Congratulations to Prof. Chan Joshi on this accomplishment. [ABSTRACT FROM AUTHOR]

Traffic congestion occurs when there is a mismatch between the demand for road use and the available capacity. The volume-delay function (VDF) can quantify the relationship between travel time and the volume of traffic on a particular link, and also provide insight into the state of a traffic system, such as whether it is congested or uncongested. In this paper, we present a VDF model that is based on the fundamental diagram and has two main components: (1) an improved VDF with fewer parameters that can handle both congested and uncongested traffic conditions, based on a fundamental diagram, and (2) a model-based VDF practical calibration framework for practical traffic applications that can determine key parameters for a link in a corridor. Our experiments using corridors in Los Angeles and Beijing demonstrate that our proposed analytical methods effectively calculate road impedance under congested conditions. The results indicate that the proposed model is superior to other existing models in terms of the root mean squared error (RMSE) and mean absolute error (MAE). In addition, our calibrated results indicate that the travel time index (TTI) in Los Angeles is 2.12, in Beijing is 1.74. The model proposed in this paper provides a useful calibration tool for enhancing model performance and improving the accuracy of travel time and speed estimates in traffic assignment. [ABSTRACT FROM AUTHOR]

As the world becomes increasingly "smaller," global governance too shifts beyond states and formal agreements to include norms and actors at all levels of government and society. Cities, in particular, are emergent actors in global affairs. This paper examines a new type of experiential learning model for this burgeoning local–global governance: academic partnerships with city governments for undergraduate international relations courses. Occidental College and Pomona College have partnered with the Los Angeles Mayor's Office to localize and adopt the United Nations Sustainable Development Goals (SDGs). This study focuses on two Spring 2021 Task Force courses, where students worked in consultation with the Mayor's Office to conduct policy research on local implementation of SDG 5 on gender equality. It analyzes the pedagogical value of the Task Force courses with a focus on student learning outcomes and challenges. Through qualitative content analysis of student reflection papers, we find that the courses generate substantial student learning, particularly in higher forms of learning, including development of research and professional skills and metacognitive reflection on "doing theory," or praxis, within the international relations discipline. Further, these partnerships also benefit the city, as they generate valuable data that inform policymaking. [ABSTRACT FROM AUTHOR]

In two studies, students at California State University, Northridge wrote papers that were checked for plagiarism using plagiarism-detection software. In the first study, half of the students in two classes were randomly selected and told by the professor that their term papers would be scanned for plagiarism using the software. Students in the remainder of each class were not informed that the software would be used. The researcher predicted that students who were explicitly warned about the use of the software would plagiarize less than students who were not, but the warning had no effect. In a second study, students wrote two papers in a series. Their knowledge about plagiarism-detection software was inversely correlated with plagiarism rates on the first paper, but no correlation was found between knowledge and plagiarism on the second paper. Instead, participants were discovered to draw repeatedly from the same sources of plagiarized material across papers. [ABSTRACT FROM PUBLISHER]

This paper explores how the Taiwanese-Chinese religious movement Yiguandao ("Way of Pervading Unity") creates a community of non-Chinese followers by utilizing Daoism-related beliefs and practices. Drawing on ethnographic data from fieldwork conducted in California in early 2018, published Yiguandao materials, and internet resources, the paper argues that Yiguandao activists specifically invest their messages in Daoist symbols, beliefs, and practices to reach out to non-Chinese sympathizers of "Asian philosophies" and eventually to establish a global and cross-cultural community of Dao followers. By discussing a case study from Los Angeles, the paper seeks to understand the patterns of Yiguandao activists' engagement with Daoism and how their efforts blend into establishing a global Daoist field. Finally, it thereby invites us to rethink the often haphazardly drawn boundaries—both by practitioners and scholars—between Daoism and other religious phenomena, including New Age, spirituality, and Chinese popular sects. [ABSTRACT FROM AUTHOR]

The aggregates are essential materials in civil engineering, they are used for railway and road constructions, for hydraulic engineering but they are also the base material of concrete. The crushed stones are exposed to several effects during their lifespan. Therefore, several tests were developed to evaluate their performance. One of the most important aspects is the resistance to degradation. However, degradation tests require special types of equipment and usually take longer than common strength tests which are more likely to be available for rock materials. Therefore, the empirical connections between strength and degradation values can be extremely useful in practice. The paper aimed to collect all available relationships and datasets from the literature that presents the relations between these different parameters - such as Aggregate Impact Value (AIV), Aggregate Crushing Value (ACV), Ten Percent Fines Value (TFV), Los Angeles Abrasion Value (LAAV), and micro-Deval Coefficient (MDE) - and rock strength parameters - such as Uniaxial Compressive Strength (UCS) and Point Load Strength Index (IS(50)) - and to provide the best-fit formula for different rock types. The paper also highlights the difficulties and limitations of the compared relationships. [ABSTRACT FROM AUTHOR]

Runtime verification (RV) refers to methods for formal reasoning about all aspects of the dynamic execution of systems, including hardware, software, and cyber-physical systems. RV includes techniques to assess and enforce correctness of a system against systemic bugs or extrinsic uncertainties. These methods are typically considered lightweight as they may not involve exhaustive verification or proofs, but they provide a higher level of rigor and versatility compared to conventional testing methods. This article introduces the extended versions of selected papers from the peer-reviewed proceedings of the 21st International Conference on Runtime Verification (RV 2021). RV 2021 was supposed to be held in Los Angeles, California, USA in November 2021, but was instead held virtually due to the global Covid-19 pandemic. [ABSTRACT FROM AUTHOR]

While infill development is widely accepted by cities as an alternative to urban sprawl, a very dearth of research has attempted to measure infill development and identify contributing factors to infill development. Filling this research gap, this paper models residential infill development in the City of Los Angeles by employing five machine learning (ML) algorithms. This paper attempts to identify the best-performing ML algorithms by comparing the performance of the ML algorithms. Of the five ML algorithms tested, the random forest (RF) and k-nearest neighbor (kNN) algorithms are selected as the best-performing algorithms. The RF algorithm ranks independent variables from most to least important. Overall, the ranks suggested that residential infill development in the City of Los Angeles is significantly influenced by the physical conditions of property and neighborhood rather than socioeconomic characteristics. Diverse land uses, good housing mixes, and rail transit accessibility also, importantly, contributed to the infill development. This finding suggests that the city's planning efforts, such as the promotion of accessory dwelling unit (ADU) development and the expansion of rail transit, can create a virtuous circle for sustainable urban development. [ABSTRACT FROM AUTHOR]

While the co-production of knowledge through community-engaged research is intended to be a reciprocally beneficial process, academic institutions have often devalued community expertise by treating community organizations as subjects rather than co-creators of knowledge. Drawing from Black Feminist Epistemology, this ethnographic study examines how one community-based organization, Los Angeles Community Action Network (LA CAN), partners with academic researchers, including their discourse around partnerships and how they challenged power dynamics between community and their university partners. This paper discusses key themes from their partnerships, including centering community members' expertise through their lived experience and forming long-term mutual relationships rooted in abolition and the Black Radical Tradition. Drawing on an analysis of LA CAN's organizing and research processes with academic partners, we discuss how the centering of community expertise and forming relationships with academics aligned on these values can help to challenge the traditional power dynamics in community-university partnerships, resulting in different ways of knowing or what LA CAN referred to as "the real data set.". [ABSTRACT FROM AUTHOR]

Philip K. Dick takes the highly computerized but ruined Los Angeles of the United States after the post-apocalyptic war as the background and brings the cyberspace struggle between androids and humans as the novel's theme, sketching a cyberpunk society in which humans and androids fight against each other. The novel Do Androids Dream of Electric Sheep? invites people to think about cyberspace and human-androids subjectivity. Inspired by Slavoj Zizek's critical theory of cyberspace, this paper uses this science-fiction force as a text to explore how contemporary American science fiction reconstructs a revolutionary human-androids subject in cyberspace, challenging human subjectivity in the urban space. Faced with human-android coexistence, Dick affirms the coexistence of multiple subjects using equal dialogue, fully exploits the advantages of androids and humans, and constructs the subject with human-androids. Through an in-depth study of androids, this paper concludes that in a human-androids coexistence space, humans and androids should not be in a master-slave relationship; instead, they are each other's constitutive Other. Humans should try to break the boundary between self and others to accept a pluralistic and open subject. [ABSTRACT FROM AUTHOR]

Water reuse with Advanced Water Treatment (AWT) is increasingly appealing for urban areas seeking water supply reliability. In cities facing water scarcity, how can large-scale reuse support reliability and how do reuse operations affect water quality, energy use, and water conservation? This paper presents a systems analysis of metropolitan-scale water reuse and its effects on water supply and quality. For the case study of Los Angeles County, California, USA, hydroeconomic modeling is used to evaluate reuse as a contributor to water supply given urban water conservation, drought-induced water scarcity, and costs and benefits for supply and demand. Results indicate that AWT can be a viable source of supply especially when coupled with conservation. Across modeled scenarios, reuse provides as much as 30% of regional supplies. New water reuse with AWT becomes viable when imported water availability is 50% or less of historic values. Existing indirect potable reuse operations in the county remain important. Systemwide energy intensity of operations increases with greater reuse in the absence of water conservation. Modeled influent flow rates to wastewater treatment plants resemble historical values, but extreme flow events could pose risks. The paper offers a holistic framework to evaluate water reuse as a component of urban water management. [ABSTRACT FROM AUTHOR]

By reducing fossil fuel use, renewable energy improves the economy, quality of life, and environment. These impacts make renewable energy forecasting crucial for lowering fossil fuel utilization. This paper aims to mathematically improve time series forecasting literature by focusing on solar irradiance applications in Los Angeles, Denver, and Hawaii solar irradiance sites. A three-phased time series forecasting hybrid method is devised for this endeavor. The ARFIMA is used to forecast the original solar irradiance time series in phase I. Next, the dataset's residuals, are retrieved by subtracting the phase I results from the observed time series to prepare the scenario for the following phase. A novel enhanced fractional Brownian motion is used for residual forecasting in phase II. The parameter estimation in phase II is implemented adaptively to capture the dynamic statistical characteristics of the time series efficiently. Finally, the phases I and II results are numerically conglomerated to form the final forecasting results in phase III. The residual forecasting part, in phase II, reveals a substantial superiority. Also, when comparing the proposed hybrid algorithm results to other existing cutting-edge algorithms applied to the same solar irradiance applications, the output demonstrates that the suggested algorithm has a significantly improved performance. [ABSTRACT FROM AUTHOR]

This article focuses on the Electrochemical Society meeting held in Los Angeles, California. The first symposium of the Physical and Analytical Electrochemistry Division focused on Durability and Reliability of Low-Temperature Fuel Cells and Fuel Cell Systems. This symposium presented Outstanding Student Paper Awards to students of various universities of the United States. For example, Vishal Mittal of the University of Connecticut got the award for his paper entitled, "Factors Accelerating Membrane Degradation Rate and the Underlying Degradation Mechanism in PEMFC." In this paper, experiments were performed to elucidate the factors and conditions important for photoelectromagnetic degradation.

The Editors of the Journal "Auditing: A Journal of Practice & Theory" invited Professor Gary L. Holstrum and Professor Theodore J. Mock to submit this synopsis of the University of Southern California Audit Judgment Symposium in the belief that many audit researchers and professionals who were not able to attend the conference would benefit from the report. A significant area of audit judgment is the evaluation of audit evidence. This synopsis of audit judgment and evidence evaluation research is based upon papers and presentations made at the 1985. The evaluation of audit evidence may be based on one of several models of inference. Audit evidence could be evaluated according to a Bayesian inference model, a non-Bayesian statistical model, a hierarchical or cascaded inference model, a causal reasoning model, or some other form of inference model. Strengths and weaknesses of various inference models were discussed at the Symposium. The Symposium began with presentations of some current behavioral science research on inference models that are expected to be relevant to audit evidence evaluation.

Background: According to the 5th edition of the Japanese Guidelines for the Treatment of Gastric Cancer, proximal gastrectomy is recommended for patients with early upper gastric cancer who can retain the distal half of the residual stomach after R0 resection. However, a large number of recent clinical studies suggest that surgical indications for proximal gastrectomy in the guidelines may be too narrow. Therefore, this meta-analysis included patients with early and advanced gastric cancer and compared short- and long-term postoperative outcomes between the two groups. At the same time, we only had high-quality clinical studies such as propensity score-matched studies and randomized controlled trials, which made our research more authentic and credible. Methods: Data were retrieved from PubMed, EMBASE, Medline, and Cochrane Library up to June 2023, and included treatment outcomes after proximal gastrectomy with double-tract reconstruction and total gastrectomy with Roux-en-Y reconstruction. The primary results were Early-phase complications(Anastomotic leakage, Anastomotic bleeding, Abdominal abscess, Abdominal infection, Pulmonary infection, Incision infection, Intestinal obstruction, Dumping syndrome, Pancreatic fistula), Late-phase complications(Intestinal obstruction, Anastomosis stricture, Dumping syndrome, Reoperation, Internal hernia, Incidence of endoscopic gastroesophageal reflux), Serious complications (≥ Grade III C-D score), Quality of life[Gastroesophageal reflux symptom evaluation (Visick score)(≥ III), Los Angeles classification(C or D)], Nutritional status(Hemoglobin, Receipt of vitamin B12 supplementation), Oncologic Outcomes(The 5-year overall survival rates). Secondary outcomes were surgical outcomes (Operative time, Estimated blood loss, Postoperative hospital stay, Number of harvested lymph nodes, Gas-passing, Postoperative mortality).The Cochrane risk-of-bias tool and Newcastle‒Ottawa scale were used to assess the quality of the included studies. Results: After screening, 11 studies were finally included, including 1154 patients. Results from the combined literature showed that total gastrectomy had a significant advantage over proximal gastrectomy with double-tract reconstruction in mean operating time (MD = 4.92, 95% CI: 0.22∼9.61 P = 0.04). However, meta-analysis results showed that Hemoglobin (MD = 7.12, 95% CI:2.40∼11.84, P = 0.003) and Receipt of vitamin B12 supplementation (OR = 0.12, 95% CI:0.05∼0.26, P < 0.00001) in the proximal gastrectomy with double-tract reconstruction group were better than those in the total gastrectomy with Roux-en-Y reconstruction group. There is no significant difference between the proximal gastrectomy with double-tract reconstruction and the total gastrectomy with Roux-en-Y reconstruction group in Early-phase complications(OR = 1.14,95% CI:0.79∼1.64, P = 0.50), Late-phase complications(OR = 1.37,95% CI:0.78∼2.39, P = 0.27), Gastroesophageal reflux symptom evaluation (Visick score)(≥ III)(OR = 0.94,95% CI:0.14∼1.07 P = 0.07), Los Angeles classification(C or D)(OR = 0.33,95% CI:0.01∼8.21, P = 0.50), the 5-year overall survival rates (HR = 1.01, 95% CI: 0.83 ~ 1.23, P = 0.89). Conclusion: Proximal gastrectomy with double-tract anastomosis is a safe and feasible treatment for upper gastric carcinoma. However, the operating time was slightly longer in the proximal gastrectomy with double-tract group compared to the total gastrectomy with Roux-en-Y group. The two groups were comparable to the total gastrectomy with Roux-en-Y group in terms of serious complications (≥ Grade III C-D score), early-phase complications, late-phase complications, and quality of life. Although the scope of proximal gastrectomy is smaller than that of total gastrectomy, it does not affect the 5-year survival rate, indicating good tumor outcomes for patients. Compared to total gastrectomy with Roux-en-Y group, proximal gastrectomy with double-tract reconstruction had higher hemoglobin levels, lower probability of vitamin B12 supplementation, and better long-term efficacy. In conclusion, proximal gastrectomy with double-tract reconstruction is considered one of the more rational surgical approaches for upper gastric cancer. [ABSTRACT FROM AUTHOR]

Self-melting ice asphalt pavement materials inhibit pavement freezing and improve driving safety. This paper aims to study the long-term salt release characteristics of self-melting ice asphalt mixtures and the impact on pavement after complete salt release. Firstly, a method to accelerate the rapid release of salt based on the Los Angeles abrasion tester. Then, long-term salt release patterns were elucidated under the influence of deicing agent dosage, type of asphalt, and type of gradation. Finally, a quantitative analysis of the pavement performance after complete salt release is conducted. The results indicate that the release efficiency of the Los Angeles abrasion tester method has increased by 91 times compared to the magnetic stirrer immersion flushing method and by 114 times compared to the natural soaking method. The SBS-modified self-melting ice asphalt mixture possesses a longer duration of salt release, but the uniformity of salt release is inferior. Salt release duration is directly proportional to the dosage of deicing agents. SMA-13 self-melting ice asphalt mixture exhibits poorer uniformity in salt release. After complete salt release, high-temperature stability of self-melting ice asphalt mixtures decreased by 31.6%, low-temperature performance decreased by 15.4%, water stability decreased by 26.7%, and fatigue life decreased by 35.9%. [ABSTRACT FROM AUTHOR]

The 2020 census reports that 61.2 million Latinxs live in the US, totaling around 19% of all residents, forming the country's largest minority population. With the growing number of Latinxs, there has been a higher level of contact between Spanish and English leading to language mixing or code-switching (CS) in mainstream American culture. This paper examines the Spanish/English CS in radio advertisements on Los Angeles's 96.3 La Mega, a bilingual radio station geared towards today's youth. Using Derrick' 2015 sentential framework for the linguistic analysis of multilingual sentences, I carry out a sentence-by-sentence analysis of the linguistic nature of the on-air bilingual advertisements. I explore both national advertisements, as well as DJ-endorsed advertisements, to discern whether they follow the patterns previously pointed out in the literature for positive consumer evaluations of Spanish/English bilingual advertisements. Furthermore, I am interested in if these advertisements are in line with the ethos of 96.3 La Mega, which prides itself on being fully bilingual. This research will shed light on the linguistic nature of contemporary strategies being used in bilingual advertisements for the US Latinx community and marketing tactics designed to encourage their consumerism. [ABSTRACT FROM AUTHOR]

This paper presents an extensive numerical study on the seismic performance of steel eccentrically braced frames (EBFs) designed according to the ASCE 7-16 standard. A series of EBF building structures ranging from 2 to 12 stories located in downtown Los Angeles are designed with different yielding links, including conventional and replaceable links. The performance of the structures is investigated through nonlinear time-history analyses (NLTHAs) under a suite of 40 ground motions, selected and scaled to match the target uniform hazard spectrum. The peak deformations are first examined to assess the performance of the buildings as well as the design procedure. Residual deformations are also evaluated and critically compared with acceptable limits, to provide insight into the downtime and recovery time of EBFs after major earthquakes. Previous studies have demonstrated that the response of stable yielding systems to major earthquakes is often accompanied by significant residual deformations, and that residual drifts exceeding 0.5% can cause hindrance to the buildings occupants. In EBFs, in addition to residual drifts, residual link rotations are also relevant and expected to be more severe due to the localization of inelastic deformations in the yielding link. For replaceable modular yielding links, significant residual link rotations after major earthquakes will hinder repairs and the link replacement process, which is one of the important design objectives. The performance of EBFs is also compared with what was observed in previous studies for buckling restrained braced frames and special moment resisting frames. In the end, the results from the extensive NLTHAs are used to establish a relationship between peak drifts and peak link rotations in EBFs. [ABSTRACT FROM AUTHOR]

This paper examines communicating about complex challenges facing populations experiencing homelessness and examining alternative ways to communicate with these populations in times of crisis. Utilizing a case study approach, the researchers focused on cities in New York and California due to the high numbers of unhoused populations and individuals experiencing homelessness within these states. Experts in crisis and emergency management have provided invaluable recommendations on the general protection of life and property; however, individuals identifying as homeless or unhoused share characteristics that heighten their risk and vulnerability, such as lower socioeconomic status, unstable resilience levels prior to a crisis, and geographic disparities. The intersection of these attributes presents unique challenges for emergency managers and relevant public administrators when implementing crisis response and communication strategies, such as one-way written and oral messaging over media and social networks, along with enacting any new protocols needed in relation to the crisis itself, like targeted outreach. This paper discusses the evolution of crisis communication for homeless and unhoused populations, national statistics, along with analysis of case studies for Los Angeles, California, and New York City, New York. The paper concludes with eight major themes related to communicating with homeless and unhoused populations during times of crises and practical recommendations for emergency managers and relevant public administrators. It is critical that representatives and advocates for populations experiencing homelessness, or are unhoused, are involved in the dialogue and planning efforts. Stable investment in communication infrastructure and crisis communication programs and services is vital to assist homeless and unhoused populations in gaining access to the Internet and cell phone providers, outreach campaigns for printed messaging, alternative locations for media reporting, and receiving critical information during crisis and noncrisis periods. In terms of messaging, crisis-related alerts (oral and written) must be reviewed to ensure clarity in tone to avoid ambiguity and identify and remove any stigmatization language to open a two-way dialogue. Emergency managers and related public administrators must use a diverse array of communication avenues and strategies, such as social media and electronic messages (i.e., cell phones, media statements, and business signage) and traditional methods (i.e., leaflets at social service providers and shelters) with a focus on creating dialogue and empowering individuals to engage and seek out services. In addition, a crisis team dedicated to communicating with homeless and unhoused populations in times of crisis is needed along with dedicated resources for staffing, communication infrastructure, programs, and services. [ABSTRACT FROM AUTHOR]

The Los Angeles basin is a significant anthropogenic source of major greenhouse gases (CO2 and CH4) and the pollutant CO, contributing significantly to regional and global climate change. We present a novel approach for monitoring the spatial and temporal distributions of greenhouse gases in the Los Angeles basin using a highresolution spectroscopic remote sensing technique. A new Fourier Transform Spectrometer called CLARS-FTS has been deployed since May 2010 at JPL's California Laboratory for Atmospheric Remote Sensing (CLARS) on Mt. Wilson, California for automated long-term measurements of greenhouse gases. The instrument design and performance of CLARS-FTS are presented. From its mountaintop location at an altitude of 1673 m, the instrument points at a programmed sequence of ground target locations in the Los Angeles basin, recording spectra of reflected near-IR solar radiation. Column-averaged dry-air mole fractions of greenhouse gases (XGHG) including XCO2, XCH4, and XCO are retrieved several times per day for each target. Spectra from a local Spectralon® scattering plate are also recorded to determine background (free tropospheric) column abundances above the site. Comparisons between measurements from LA basin targets and the Spectralon® plate provide estimates of the boundary layer partial column abundances of the measured species. Algorithms are described for transforming the measured interferograms into spectra, and for deriving column abundances from the spectra along with estimates of the measurement precision and accuracy. The CLARS GHG measurements provide a means to infer relative, and possibly absolute, GHG emissions. [ABSTRACT FROM AUTHOR]

A biography of Charles Carleton Hirt, founding member of the non-profit organization American Choral Directors Association, is presented. He was born on November 4, 1911, in Los Angeles, California, to Adolph Hirt and Della Belle Hirt and attended an elementary school in Glendale, California. In 1941, Hirt was offered a teaching assignment at the Glendale Junior College by the Glendale Board of Education.

The article focuses on the career of Cheng-Ming Chuong, a developmental biologist at the University of Southern California in Los Angeles. Chuong has interest on how feathers are generated in adult birds. He decided to try to track down the location of stem cells in feathers. Chuong and his team discovered that in flight feathers, the ring of stem cells tilts towards the side where the quill arises. He plans to continue his characterization of feather stem cells.

This paper offers a theoretical investigation about the notion of "skills" within a geographical approach. For spatial practices, the challenge is probably less about understanding what individuals do than their ways of doing. Building on an empirical survey about the tourists practices in Los Angeles, the paper first supports the idea that each spatial configuration is an issue for every individual, a gathering of spatial stakes that everyone must address. Then, it argues that the ways in which individuals deal with these stakes depend on their skills. Defining skills as "the mastery of techniques", the article engages a critical discussion with French pragmatic sociology (Boltanski and Thévenot) and geography (Lussault) as well as upon works in anthropology (Ingold). [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive modeling framework for large-scale agent-based multimodal transportation simulation tailored to the complex urban environments of megacities, with a specific focus on the Greater Los Angeles (LA) area. The framework leverages the Multi-Agent Transport Simulation (MATSim) toolkit, which addresses the evolving challenges posed by urbanization and technology-driven shifts in human mobility patterns. The framework enables the generation of explicit travel trajectories for a representative 10% sample population of LA County, comprising over one million individuals. To ensure the model's validity, an efficient network calibration algorithm is proposed with rigorous validation using publicly available traffic count data. This paper underscores the development and configuration of the agent-based simulation model for LA, providing a robust foundation for large-scale urban mobility simulations and advancing our understanding of the intricacies of megacities. [ABSTRACT FROM AUTHOR]

Chile, recognized as one of the world's most earthquake-prone nations, has gained valuable insights from significant earthquakes, such as those in 1985 and 2010, which have influenced updates to the nation's design codes. Although Chile's seismic design approach has been largely effective in recent earthquakes and demonstrated an "operational" performance level in most structures, performance-based design (PBD) methods have not yet been officially incorporated as valid approaches in the Chilean seismic design codes for buildings. However, in 2017, the Chilean Association on Seismology and Earthquake Engineering (ACHISINA) introduced a PBD approach, primarily for verification purposes, based on the Los Angeles Tall Buildings Structural Design Council (LATBSDC) framework. In this work, firstly, we provide an overview of Chile's PBD methodology, focusing on the thresholds for various performance levels. These levels are established through experimental and numerical analysis, correlating performance with permissible damage levels. The second part of the paper examines the seismic performance of a residential building, designed before the 2010 Maule earthquake and subsequently damaged, using Chile's PBD guidelines. This case study highlights the implementation and effectiveness of PBD for assessing seismic resilience in Chilean structures. [ABSTRACT FROM AUTHOR]

This study aims to forecast New York and Los Angeles gasoline spot prices on a daily frequency. The dataset includes gasoline prices and a big set of 128 other relevant variables spanning the period from 17 February 2004 to 26 March 2022. These variables were fed to three tree-based machine learning algorithms: decision trees, random forest, and XGBoost. Furthermore, a variable importance measure (VIM) technique was applied to identify and rank the most important explanatory variables. The optimal model, a trained random forest, achieves a mean absolute percent error (MAPE) in the out-of-sample of 3.23% for the New York and 3.78% for the Los Angeles gasoline spot prices. The first lag, AR (1), of gasoline is the most important variable in both markets; the top five variables are all energy-related. This paper can strengthen the understanding of price determinants and has the potential to inform strategic decisions and policy directions within the energy sector, making it a valuable asset for both industry practitioners and policymakers. [ABSTRACT FROM AUTHOR]

Objectives: The objective of this paper is to improve understanding of the spatial relationship of the built environment (BE) with urban gun crime and how the influence of environmental features varies across geographic location and socioeconomic context. Specifically, we analyze associations between incidents of reported firearms violence and distance to built environment features, accounting for neighborhood socio-economic status. Methods: This study compares reported crime data with the outputs from a Monte Carlo Simulation using the Network Cross-K Function for Stochastic Spatial Events on street networks. Where data is available, we examine ten features—transit stations, universities/colleges, convenience stores, gas stations, liquor licenses, alcohol outlets, tobacco retailers, lodging, restaurants, and schools—across diverse metropolitan areas to uncover features that exert "attractive" or "repellent" influence on firearms violence. We present results from four U.S. cities and examine how results vary by socio-economic status of census tracts. Results: Attractive features include tobacco retailers in Pittsburgh, hotels/motels, alcohol outlets, and restaurants in New Orleans, and rail transit stations in Los Angeles. We uncover localized attractive and repellent relationships within the lowest and highest socio-economic areas. We also identify several firearms crime repellents, including universities/colleges and public/private schools. Conclusions: We find that attractors vary by city and socio-economic status, indicating that the unique underlying environmental context of each city facilitates firearms crime differently. [ABSTRACT FROM AUTHOR]

Introduction: The COVID-19 pandemic disproportionately affected older adults, particularly those with pre-existing chronic health conditions. To address the health disparity and challenges faced by under-resourced African American older adults in South Los Angeles during this period, we implemented a hybrid (virtual/in-person), pre-post, community-based participatory intervention research project utilizing a faith-based lay health advisor model (COVID-19 Health Ambassador Program (CHAP)). We recruited COVID-19 Health Ambassadors (CHAs) and African American older adults (participants) from faith-based organizations who partook in CHA-led meetings and follow-ups that educated and supported the participants. This paper seeks to evaluate this intervention's implementation using the Consolidated Framework for Implementation Research (CFIR) as a reporting tool with an emphasis on fidelity, challenges, and adaptations based on data collected via stakeholder interviews and surveys. Results: CHAP was delivered to 152 participants by 19 CHAs from 17 faith-based organizations. CHAs assisted with chronic disease management, resolved medication-related challenges, encouraged COVID-19 vaccination, reduced psychological stress and addressed healthcare avoidance behaviors such as COVID-19 vaccine hesitancy among the participants. Challenges encountered include ensuring participant engagement and retention in the virtual format and addressing technological barriers for CHAs and participants. Adaptations made to better suit the needs of participants included providing communication tools and additional training to CHAs to improve their proficiency in using virtual platforms in addition to adapting scientific/educational materials to suit our participants' diverse cultural and linguistic needs. Conclusion: The community-centered hybrid approach in addition to our partnership with faith-based organizations and their respective COVID-19 health ambassadors proved to be essential in assisting underserved African American older adults manage chronic health conditions and address community-wide health disparities during the COVID-19 pandemic. Adaptability, cultural sensitivity, and teamwork are key to implementing health interventions especially in underserved populations. [ABSTRACT FROM AUTHOR]

Mega-events like the Olympics and the Football World Cup routinely harm host cities and societies, largely due to their linkages with ambitious urban development agendas. Concurrently, resident protest has had only limited success in mitigating mega-event-related damages, notwithstanding the growth of resistance networks at local, national, and transnational scales. Contextualised within the broader processes of the Agenda 2020 and New Norm Olympic reforms, this paper explores the tactics of protest against the Summer Olympics in Paris 2024 and Los Angeles 2028. In so doing, the paper demonstrates how the reforms have moderated some of the more egregious aspects of mega-event harm, while nevertheless preserving some fundamental problems with hosting, albeit in more diffuse or disguised forms. The paper makes sense of these processes through the notion of Potemkinism, conceptualised as a dynamic between the superficial and the substantive, and predicated on obfuscation or concealment. The paper also presents a taxonomy of tactics adopted by host city residents to counter the problems that persist in these processes of Potemkin reform. [ABSTRACT FROM AUTHOR]