Hasil untuk "United States local history"

Mikhail G. Katz

Infinitesimals have seen ups and downs in their tumultuous history. In the 18th century, d'Alembert set the tone by describing infinitesimals as chimeras. Some adversaries of infinitesimals, including Moigno and Connes, picked up on the term. We highlight the work of Cauchy, Noël, Poisson and Riemann. We also chronicle reactions by Moigno, Lamarle and Cantor, and signal the start of a revival with Peano.

Kiwhan Song, Boyuan Chen, Max Simchowitz et al.

Classifier-free guidance (CFG) is a key technique for improving conditional generation in diffusion models, enabling more accurate control while enhancing sample quality. It is natural to extend this technique to video diffusion, which generates video conditioned on a variable number of context frames, collectively referred to as history. However, we find two key challenges to guiding with variable-length history: architectures that only support fixed-size conditioning, and the empirical observation that CFG-style history dropout performs poorly. To address this, we propose the Diffusion Forcing Transformer (DFoT), a video diffusion architecture and theoretically grounded training objective that jointly enable conditioning on a flexible number of history frames. We then introduce History Guidance, a family of guidance methods uniquely enabled by DFoT. We show that its simplest form, vanilla history guidance, already significantly improves video generation quality and temporal consistency. A more advanced method, history guidance across time and frequency further enhances motion dynamics, enables compositional generalization to out-of-distribution history, and can stably roll out extremely long videos. Project website: https://boyuan.space/history-guidance

Robert van Leeuwen

The early history of string theory is marked by a shift from strong interaction physics to quantum gravity. The first string models and associated theoretical framework were formulated in the late 1960s and early 1970s in the context of the S-matrix program for the strong interactions. In the mid-1970s, the models were reinterpreted as a potential theory unifying the four fundamental forces. This paper provides a historical analysis of how string theory was developed out of S-matrix physics, aiming to clarify how modern string theory, as a theory detached from experimental data, grew out of an S-matrix program that was strongly dependent upon observable quantities. Surprisingly, the theoretical practice of physicists already turned away from experiment before string theory was recast as a potential unified quantum gravity theory. With the formulation of dual resonance models (the "hadronic string theory"), physicists were able to determine almost all of the models' parameters on the basis of theoretical reasoning. It was this commitment to "non-arbitrariness", i.e., a lack of free parameters in the theory, that initially drove string theorists away from experimental input, and not the practical inaccessibility of experimental data in the context of quantum gravity physics. This is an important observation when assessing the role of experimental data in string theory.

Edwin Dickinson, Melody W. Young, Daniel Tanis et al.

Parrots (Order: Psittaciformes) represent one of the most striking and ecomorphologically diverse avian clades, spanning more than two orders of magnitude in body size with populations occupying six continents. The worldwide diaspora of parrots is largely due to the pet trade, driven by human desire for bright, colorful, and intelligent animals as companions. Some introduced species have aptly inserted themselves into the local ecosystem and established successful breeding colonies all around the globe. Notably, the United States is home to several thriving populations of introduced species including red-masked parakeets (<i>Psittacara erythrogenys</i>), monk parakeets (<i>Myiopsitta monachus</i>), nanday conures (<i>Aratinga nenday</i>), and red-crowned amazons (<i>Amazona viridigenalis</i>). Their incredible success globally begs the question as to how these birds adapt so readily to novel environments. In this commentary, we trace parrots through evolutionary history, contextualize existent naturalized parrot populations within the contiguous United States, and provide a phylogenetic regression analysis of body mass and brain size based on success in establishing breeding populations. The propensity for a parrot species to become established appears to be phylogenetically driven. Notably, parrots in the family Cacatuidae and Neotropical <i>Pyrrhua</i> appear to be poor at establishing themselves in the United States once released. Although brain size among Psittaciformes did not show a significant impact on successful breeding in the continental United States, we propose that the success of parrots can be attributed to their charismatic nature, significant intelligence relative to other avian lineages, and behavioral flexibility.

Leonid I. Gurvits

Space Very Long Baseline Interferometry is a radio astronomy technique distinguished by a record-high angular resolution reaching single-digit microseconds of arc. The paper provides a brief account of the history of developments of this technique over the period 1960s-2020s.

Doreen Fraser, Maria Papageorgiou

The formulation of a measurement theory for relativistic quantum field theory (QFT) has recently been an active area of research. In contrast to the asymptotic measurement framework that was enshrined in QED, the new proposals aim to supply a measurement framework for measurements in local spacetime regions. This paper surveys episodes in the history of quantum theory that contemporary researchers have identified as precursors to their own work and discusses how they laid the groundwork for current approaches to local measurement theory for QFT.

Chaoqun Lu, Zhen Yu, Jien Zhang et al.

The atmospheric concentration of nitrous oxide (N2O) has increased by 23% since the pre‐industrial era, which substantially destructed the stratospheric ozone layer and changed the global climate. However, it remains uncertain about the reasons behind the increase and the spatiotemporal patterns of soil N2O emissions, a primary biogenic source. Here, we used an integrative land ecosystem model, Dynamic Land Ecosystem Model (DLEM), to quantify direct (i.e., emitted from local soil) and indirect (i.e., emissions related to local practices but occurring elsewhere) N2O emissions in the contiguous United States during 1900–2019. Newly developed geospatial data of land‐use history and crop‐specific agricultural management practices were used to force DLEM at a spatial resolution of 5 arc‐min by 5 arc‐min. The model simulation indicates that the U.S. soil N2O emissions totaled 0.97 ± 0.06 Tg N year−1 during the 2010s, with 94% and 6% from direct and indirect emissions, respectively. Hot spots of soil N2O emission are found in the US Corn Belt and Rice Belt. We find a threefold increase in total soil N2O emission in the United States since 1900, 74% of which is from agricultural soil emissions, increasing by 12 times from 0.04 Tg N year−1 in the 1900s to 0.51 Tg N year−1 in the 2010s. More than 90% of soil N2O emission increase in agricultural soils is attributed to human land‐use change and agricultural management practices, while increases in N deposition and climate warming are the dominant drivers for N2O emission increase from natural soils. Across the cropped acres, corn production stands out with a large amount of fertilizer consumption and high‐emission factors, responsible for nearly two‐thirds of direct agricultural soil N2O emission increase since 1900. Our study suggests a large N2O mitigation potential in cropland and the importance of exploring crop‐specific mitigation strategies and prioritizing management alternatives for targeted crop types.

John Aloysius Zinda, L. Williams, David L. Kay et al.

Abstract Growing flood risks raise difficult questions regarding risk perception, protective actions, and government response. Drawing on behavioral decision theory, protection motivation theory, and the protective action decision model, we examine the roles risk salience and immediacy, response efficacy, and trust in government authorities play in perceptions of flood risk and adoption of protective actions, with a focus on flood insurance. Data come from focus group discussions conducted in 2 flood-affected neighborhoods in Troy, New York, United States of America. Troy has a history of flooding, including major floods linked to Hurricane Irene in 2011. While several participants had vivid memories of past floods, overall salience of flood risk was low. While they recognized responsiveness of local government at the time of hazard events, they expressed concern about inadequate preparation for future disasters. Participants expressed concern about flood insurance, citing costs, inadequate coverage, and arduous procedures needed to file claims. They expressed distrust in the institutions surrounding flood insurance. We argue that emergency managers will need to be responsive to people's multiple concerns in order to build the awareness and trust on which effective natural hazard preparedness depends.

Yeonwoo Kim, Ahyoung Lee, C. Cubbin

Background This study aims to examine the effect of time‐variant perceived neighborhood social cohesion, perceived neighborhood physical disorder, and local crime on cardiovascular disease (CVD) incidence from 2006 through 2016. Methods and Results We obtained data from the Health & Retirement Study. Respondents aged ≥50 years and with no recorded history of CVD until 2006 (N=8826) were included and followed for 10 years. Cox proportional hazards models were estimated with CVD incidence as an outcome variable and time‐variant social environment factors (perceived neighborhood social cohesion, perceived neighborhood physical disorder, and local crime) as exposures, after controlling for sociodemographic factors and CVD‐related risk/protective factors. Our results showed that perceived neighborhood social cohesion was associated with CVD among Black respondents, but not Hispanic and White respondents. Perceived neighborhood physical disorder and local crime rates were not associated with CVD incidence across all racial and ethnic groups. Conclusions The results demonstrate that perceptions of favorable social environments need to be considered to reduce CVD risk among Black adults. Further research is needed to identify different pathways through which living in favorable social environments benefits cardiovascular health by racial and ethnic groups.

Lara A. Roman, Indigo J. Catton, E. Greenfield et al.

Municipal leaders are pursuing ambitious goals to increase urban tree canopy (UTC), but there is little understanding of the pace and socioecological drivers of UTC change. We analyzed land cover change in Philadelphia, Pennsylvania (United States) from 1970–2010 to examine the impacts of post-industrial processes on UTC. We interpreted land cover classes using aerial imagery and assessed historical context using archival newspapers, agency reports, and local historical scholarship. There was a citywide UTC increase of +4.3 percentage points. Substantial UTC gains occurred in protected open spaces related to both purposeful planting and unintentional forest emergence due to lack of maintenance, with the latter phenomenon well-documented in other cities located in forested biomes. Compared to developed lands, UTC was more persistent in protected open spaces. Some neighborhoods experienced substantial UTC gains, including quasi-suburban areas and depopulated low-income communities; the latter also experienced decreasing building cover. We identified key processes that drove UTC increases, and which imposed legacies on current UTC patterns: urban renewal, urban greening initiatives, quasi-suburban developments, and (dis)investments in parks. Our study demonstrates the socioecological dynamism of intra-city land cover changes at multi-decadal time scales and the crucial role of local historical context in the interpretation of UTC change.

Ming-xu Zhang, Congcong Wang, Ru Zhang et al.

Owing to modern developments in the traditional medicine industry, more people now acknowledge the efficacy of traditional medicine. As the demand for herbal medicines gradually increases, the focus of the industry will shift to how to increase production while maintaining the high quality of raw materials and final products to promote the international trade in herbal medicines. In the long history of herbal medicine, many countries and regions have formulated relevant standards to regulate the cultivation of local herbs to ensure the safety and reliability of the products. Due to cultural and historical differences, the policies for formulating herbal cultivation standards vary greatly between regions, which hinders the international trade of herbal medicines. This paper collates the guidelines of good agricultural and collection practices of the European Union, China, World Health Organization and the United States, and makes a comprehensive comparison of its contents such as production environments, production area suitability, air, soil, and water standard regulations, inter alia. This article aims to explore the differences in good agriculture and collection practice in herbal medicine in various regions and provides a reference for the development of international guidelines for herbal quality management, which will aid with the development of herbal medicine quality standardization globally and exchange services in the trade of herbal medicines.

Amrit Nanaiah, Frederick Southwick, Venkat Chekuri et al.

# Background Rural communities in India are vulnerable to the global pandemic of severe acute respiratory coronavirus 2 (SARS-CoV-2) due to a lack of resources and delayed access to information. To address the challenges faced by Primary Health Centers, the Karuna Trust-Lopamudra Medical Center COVID-19 High Dependency Unit (KLCHDU), a collaboration between a local hospital, a non-governmental organization, infectious disease physicians from an academic medical center in the United States, and a local citizens council, was established in May 2021. This collaboration implemented diagnostic and management COVID-19 protocols recommended by the Infectious Diseases Society of America, the National Institute of Health, and the U.S. Centers for Disease Control and provided basic training on recommended practices to Primary Health Center and other local healthcare workers. # Methods All local patients between 1 May 2021 through 31 July 2021 who tested positive for SARS-CoV-2 with a rapid antigen test or polymerase chain reaction test were admitted to the KLCHDU and were included in this study. Patient demographics, medical history, hospital course, and laboratory findings were evaluated to determine the outcomes of patients treated within this unique healthcare model. # Results Eighty-three patients (54% male) qualified for inclusion during the study period. Common comorbidities included hypertension (52%), diabetes mellitus (48%), and coronary heart disease (10%). Nearly one-third of patients had received at least one dose of SARS-CoV-2 vaccine. The most frequently administered hospital medications were dexamethasone (65%), low molecular weight heparin (54%), and remdesivir (53%). The average absolute leukocyte count was 1534 cells/µL, average blood glucose was 182 mg/dL, average D-dimer was 849 ng/mL, and average NEW-2 score on admission and discharge was 4.4 and 3.2. The average duration of hospital stay was five days. Eleven (13%) patients were prescribed supplemental oxygen at discharge and one patient died from infection complications. # Conclusions Our data show a duration of inpatient hospitalization and mortality rate on the lower end of most published data. The results of our study encourage allocation of resources based on recommended protocols and the use of telehealth for collaboration and resource sharing.

Lauren Roper, M. A. Hall, Amanda Cohn

Qianwen Zhang, Tongyin Li, Qiushuang Wang et al.

The United States (U.S.) consumed over 80 billion servings of tea, approximately 3.8 billion gallons, in the year of 2018. With the vast majority of tea demand being met by importation, the United States became the third largest tea importer worldwide after Russia and Pakistan. As demand for domestically produced tea increases and growers expressing increasing interest in growing and producing tea, tea production became an emerging industry in the United States. Compared to major tea producing countries with centuries of growing history, tea production in the United States is limited and requires research support in many aspect of tea production including selecting suitable cultivars adapted to local climatic conditions. This study evaluated nine tea cultivars, including ‘BL1,’ ‘BL2,’ ‘Black Sea,’ ‘Christine’s Choice,’ ‘Dave’s Fave,’ ‘Large Leaf,’ ‘Small Leaf,’ ‘Sochi,’ and ‘var. assamica,’ for plant growth, leaf morphological characteristics, cold tolerance, and leaf biochemical compositions when grown in Mississippi United States with a subtropical climate. The nine tested cultivars had varying plant growth indices (PGI) and varying degrees of cold tolerance to freezing temperatures in winter, but resumed healthy growth the following spring. ‘BL2’ showed the highest PGI of 104.53 cm by February 2019, which might be helpful toward suppressing weed and early establishment of tea plantation. The nine cultivars also showed varying leaf characteristics in terms of leaf length, width, area, fresh and dry weights, and new shoot weight. There existed a diversity in leaf biochemical composition including soluble solids, carbohydrates, total polyphenols (TP), free amino acids (AA), L-theanine and caffeine among the nine cultivars and among different harvesting seasons of spring, summer, and fall within a certain cultivar. The nine cultivars in this study generally grow well in local environment. All tea samples collected from nine cultivars and three seasons were considered suitable for green tea processing with low TP/AA ratios ranging from 1.72 to 3.71 in this study.

Gustavo Rodrigues Rocha, Dean Rickles, Florian J. Boge

It will be presented in this chapter a historical account of the consistent histories interpretation of quantum mechanics based on primary and secondary literature. Firstly, the formalism of the consistent histories approach will be outlined. Secondly, the works by Robert Griffiths and Roland Omnès will be discussed. Griffiths' seminal 1984 paper, the first physicist to have proposed a consistent-histories interpretation of quantum mechanics, followed by Omnès' 1990 paper, were instrumental to the consistent-histories model based on Boolean logic. Thirdly, Murray Gell-Mann and James Hartle's steps to their own version of consistent-histories approach, motivated by a cosmological perspective, will then be described and evaluated. Gell-Mann and Hartle understood that spontaneous decoherence could path the way to a concrete physical model to Griffiths' consistent histories. Moreover, the collective biography of these figures will be put in the context of the role played by the Santa Fe Institute, co-founded by Gell-Mann in 1984 in Santa Fe, New Mexico, where Hartle is also a member of the external faculty.

Sarwar J. Minar, Abdul Halim

Recent event of ousting Rohingyas from Rakhine State by the Tatmadaw provoked worldwide public-and-academic interest in history and social evolution of the Rohingyas, and this is to what the article is devoted. As the existing literature presents a debate over Who are the Rohingyas?, and How legitimate is their claim over Rakhine State?, the paper reinvestigates the issues using a qualitative research method. Compiling a detailed history, the paper finds that Rohingya community developed through historically complicated processes marked by invasions and counter-invasions. The paper argues many people entered Bengal from Arakan before British brought people into Rakhine state. The Rohingyas believe Rakhine State is their ancestral homeland and they developed a sense of Ethnic Nationalism. Their right over Rakhine State is as significant as other groups. The paper concludes that the UN must pursue solution to the crisis and the government should accept the Rohingyas as it did the land or territory.

M. White, Frances Babcock, N. Hayes et al.

C. Dai, M. Vazifeh, Chen-Hsiang Yeang et al.

The population of the United States is shaped by centuries of migration, isolation, growth, and admixture between ancestors of global origins. Here, we assemble a comprehensive view of recent population history by studying the ancestry and population structure of over 32,000 individuals in the US using genetic, ancestral birth origin, and geographic data from the National Geographic Genographic Project. We identify migration routes and barriers that reflect historical demographic events. We also uncover the spatial patterns of relatedness in subpopulations through the combination of haplotype clustering, ancestral birth origin analysis, and local ancestry inference. Examples of these patterns include substantial substructure and heterogeneity in Hispanics/Latinos, isolation-by-distance in African Americans, elevated levels of relatedness and homozygosity in Asian immigrants, and fine-scale structure in European descents. Taken together, our results provide detailed insights into the genetic structure and demographic history of the diverse US population.

Shivika Trivedi, Charnetta L. Williams, Elizabeth A Torrone et al.

OBJECTIVE To describe recent syphilis trends among pregnant women and to evaluate the prevalence of reported high-risk behaviors in this population. METHODS We analyzed U.S. national case report data for 2012-2016 to assess trends among pregnant women with all stages of syphilis. Risk behavior data collected through case interviews during routine local health department investigation of syphilis cases were used to evaluate the number of pregnant women with syphilis reporting these behaviors. RESULTS During 2012-2016, the number of syphilis cases among pregnant women increased 61%, from 1,561 to 2,508, and this increase was observed across all races and ethnicities, all women aged 15-45 years, and all U.S. regions. Of 15 queried risk factors, including high-risk sexual behaviors and drug use, 49% of pregnant women with syphilis did not report any in the past year. The most commonly reported risk behaviors were a history of a sexually transmitted disease (43%) and more than one sex partner in the past year (30%). CONCLUSION Syphilis cases among pregnant women increased from 2012 to 2016, and in half, no traditional behavioral risk factors were reported. Efforts to reduce syphilis among pregnant women should involve increasing health care provider awareness of the Centers for Disease Control and Prevention and the American College of Obstetricians and Gynecologists' recommendations, which include screening all pregnant women for syphilis at the first prenatal visit and rescreening high-risk women during the third trimester and at delivery. Health care providers should also consider local syphilis prevalence in addition to individual reported risk factors when deciding whether to repeat screening.

Livia O Loureiro, Mark D Engstrom, Burton K Lim

Although many processes of diversification have been described to explain variation of morphological traits within clades that have obvious differentiation among taxa, not much is known about these patterns in complexes of cryptic species. Molossus is a genus of bats that is mainly Neotropical, occurring from the southeastern United States to southern Argentina, including the Caribbean islands. Molossus comprises some groups of species that are morphologically similar but phylogenetically divergent, and other groups of species that are genetically similar but morphologically distinct. This contrast allows investigation of unequal trait diversification and the evolution of morphological and behavioural characters. In this study, we assessed the role of phylogenetic history in a genus of bat with three cryptic species complexes, and evaluated if morphology and behavior are evolving concertedly. The Genotype by Sequence genomic approach was used to build a species-level phylogenetic tree for Molossus and to estimate the ancestral states of morphological and echolocation call characters. We measured the correlation of phylogenetic distances to morphological and echolocation distances, and tested the relationship between morphology and behavior when the effect of phylogeny is removed. Morphology evolved via a mosaic of convergence and stasis, whereas call design was influenced exclusively through local adaptation and convergent evolution. Furthermore, the frequency of echolocation calls is negatively correlated with the size of the bat, but other characters do not seem to be evolving in concert. We hypothesize that slight variation in both morphology and behaviour among species of the genus might result from niche specialization, and that traits evolve to avoid competition for resources in similar environments.