Modeling Relations between Compacted and Uncompacted Crown Ratio for the Northern United States

Abstract Tree crown ratio is useful in various applications such as prediction of tree mortality probabilities, growth potential, and fire behavior. Crown ratio is commonly assessed in two ways: (1) compacted crown ratio (CCR—lower branches visually moved upwards to fill missing foliage gaps) and (2) uncompacted crown ratio (UNCR—no missing foliage adjustment). The national forest inventory of the United States measures CCR on all trees, whereas only a subset of trees also are assessed for UNCR. Models for 27 species groups are presented to predict UNCR for the northern United States. The model formulation is consistent with those developed for other US regions while also accounting for the presence of repeated measurements and heterogeneous variance in a mixed-model framework. Ignoring random-effects parameters, the fit index values ranged from 0.43 to 0.78, and root mean squared error spanned 0.08–0.15; considerable improvements in both goodness-of-fit statistics were realized via inclusion of the random effects. Comparison of UNCR predictions with models developed for the southern United States exhibited close agreement, whereas comparisons with models used in Forest Vegetation Simulator variants indicated poor association. The models provide additional analytical flexibility for using the breadth of northern region data in applications where UNCR is the appropriate crown characteristic.

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Proportion of Individuals With Past-Year Suicidal Ideation Who Attempted Suicide Over the Past 10 Years in the United States, and the Influence of Age and Sex

Crisis ◽

10.1027/0227-5910/a000690 ◽

2020 ◽

pp. 1-5

Author(s):

Shannon Lange ◽

Courtney Bagge ◽

Charlotte Probst ◽

Jürgen Rehm

Keyword(s):

United States ◽

Suicidal Ideation ◽

Random Effects ◽

Attempted Suicide ◽

Suicide Attempts ◽

The United States ◽

Individual Level ◽

The Past ◽

Meta Analyses ◽

Age Category

Abstract. Background: In recent years, the rate of death by suicide has been increasing disproportionately among females and young adults in the United States. Presumably this trend has been mirrored by the proportion of individuals with suicidal ideation who attempted suicide. Aim: We aimed to investigate whether the proportion of individuals in the United States with suicidal ideation who attempted suicide differed by age and/or sex, and whether this proportion has increased over time. Method: Individual-level data from the National Survey on Drug Use and Health (NSDUH), 2008–2017, were used to estimate the year-, age category-, and sex-specific proportion of individuals with past-year suicidal ideation who attempted suicide. We then determined whether this proportion differed by age category, sex, and across years using random-effects meta-regression. Overall, age category- and sex-specific proportions across survey years were estimated using random-effects meta-analyses. Results: Although the proportion was found to be significantly higher among females and those aged 18–25 years, it had not significantly increased over the past 10 years. Limitations: Data were self-reported and restricted to past-year suicidal ideation and suicide attempts. Conclusion: The increase in the death by suicide rate in the United States over the past 10 years was not mirrored by the proportion of individuals with past-year suicidal ideation who attempted suicide during this period.

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Mathematical pattern of Kessler psychological distress distribution in the general population of the U.S. and Japan

BMC Psychiatry ◽

10.1186/s12888-021-03198-y ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Shinichiro Tomitaka ◽

Toshiaki A. Furukawa

Keyword(s):

United States ◽

General Population ◽

National Survey ◽

Goodness Of Fit ◽

Quadratic Function ◽

The United States ◽

Depression Screening ◽

Distribution Model ◽

Epidemiological Surveys ◽

Screening Scale

Abstract Background Although the 6-item Kessler psychological scale (K6) is a useful depression screening scale in clinical settings and epidemiological surveys, little is known about the distribution model of the K6 score in the general population. Using four major national survey datasets from the United States and Japan, we explored the mathematical pattern of the K6 distributions in the general population. Methods We analyzed four datasets from the National Health Interview Survey, the National Survey on Drug Use and Health, and the Behavioral Risk Factor Surveillance System in the United States, and the Comprehensive Survey of Living Conditions in Japan. We compared the goodness of fit between three models: exponential, power law, and quadratic function models. Graphical and regression analyses were employed to investigate the mathematical patterns of the K6 distributions. Results The exponential function had the best fit among the three models. The K6 distributions exhibited an exponential pattern, except for the lower end of the distribution across the four surveys. The rate parameter of the K6 distributions was similar across all surveys. Conclusions Our results suggest that, regardless of different sample populations and methodologies, the K6 scores exhibit a common mathematical distribution in the general population. Our findings will contribute to the development of the distribution model for such a depression screening scale.

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Japan's Role in Asia-Pacific Cooperation

The Annals of the American Academy of Political and Social Science ◽

10.1177/0002716291513001003 ◽

1991 ◽

Vol 513 (1) ◽

pp. 25-37 ◽

Cited By ~ 2

Author(s):

SABURO OKITA

Keyword(s):

United States ◽

Economic Growth ◽

International Economic ◽

The United States ◽

Growth Potential ◽

The Other ◽

Asia Pacific ◽

Asia Pacific Economic Cooperation ◽

Rapid Economic Growth ◽

International Trading

The Asia-Pacific countries achieved rapid economic growth with the flying-goose model in the 1980s, growth buttressed by export-oriented development strategies and the policy culture in these countries. While Japan and the other Asia-Pacific countries still have strong growth potential, many problems remain, including trade imbalances with the United States and the rise of protectionism there, the Asia-Pacific economies' vulnerability, and the need to consolidate the infrastructure for growth. It is imperative that Japan contribute to the development of the region by responding effectively to these issues and that it strengthen the international trading arrangements by promoting Asia-Pacific cooperation premised on openness. Given the region's great internal diversity, Asia-Pacific economic cooperation can well serve as a model for international economic coordination.

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Laurel Wilt: Current and Potential Impacts and Possibilities for Prevention and Management

Forests ◽

10.3390/f12020181 ◽

2021 ◽

Vol 12 (2) ◽

pp. 181

Author(s):

Rabiu O. Olatinwo ◽

Stephen W. Fraedrich ◽

Albert E. Mayfield

Keyword(s):

United States ◽

Tree Mortality ◽

The United States ◽

Persea Americana ◽

Laurel Wilt ◽

Important Species ◽

Invasive Insects ◽

Raffaelea Lauricola ◽

Redbay Ambrosia Beetle ◽

The Impact

In recent years, outbreaks of nonnative invasive insects and pathogens have caused significant levels of tree mortality and disturbance in various forest ecosystems throughout the United States. Laurel wilt, caused by the pathogen Raffaelea lauricola (T.C. Harr., Fraedrich and Aghayeva) and the primary vector, the redbay ambrosia beetle (Xyleborus glabratus Eichhoff), is a nonnative pest-disease complex first reported in the southeastern United States in 2002. Since then, it has spread across eleven southeastern states to date, killing hundreds of millions of trees in the plant family Lauraceae. Here, we examine the impacts of laurel wilt on selected vulnerable Lauraceae in the United States and discuss management methods for limiting geographic expansion and reducing impact. Although about 13 species belonging to the Lauraceae are indigenous to the United States, the highly susceptible members of the family to laurel wilt are the large tree species including redbay (Persea borbonia (L.) Spreng) and sassafras (Sassafras albidum (Nutt.) Nees), with a significant economic impact on the commercial production of avocado (Persea americana Mill.), an important species native to Central America grown in the United States. Preventing new introductions and mitigating the impact of previously introduced nonnative species are critically important to decelerate losses of forest habitat, genetic diversity, and overall ecosystem value.

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Mixed Models as a Tool for Comparing Groups of Time Series in Plant Sciences

Plants ◽

10.3390/plants10020362 ◽

2021 ◽

Vol 10 (2) ◽

pp. 362

Author(s):

Ioannis Spyroglou ◽

Jan Skalák ◽

Veronika Balakhonova ◽

Zuzana Benedikty ◽

Alexandros G. Rigas ◽

...

Keyword(s):

Time Series ◽

Random Effects ◽

Mixed Models ◽

Mixed Model ◽

Repeated Measurements ◽

Time Series Models ◽

Additional Time ◽

Biotic Stresses ◽

Viable Solution ◽

Long Time

Plants adapt to continual changes in environmental conditions throughout their life spans. High-throughput phenotyping methods have been developed to noninvasively monitor the physiological responses to abiotic/biotic stresses on a scale spanning a long time, covering most of the vegetative and reproductive stages. However, some of the physiological events comprise almost immediate and very fast responses towards the changing environment which might be overlooked in long-term observations. Additionally, there are certain technical difficulties and restrictions in analyzing phenotyping data, especially when dealing with repeated measurements. In this study, a method for comparing means at different time points using generalized linear mixed models combined with classical time series models is presented. As an example, we use multiple chlorophyll time series measurements from different genotypes. The use of additional time series models as random effects is essential as the residuals of the initial mixed model may contain autocorrelations that bias the result. The nature of mixed models offers a viable solution as these can incorporate time series models for residuals as random effects. The results from analyzing chlorophyll content time series show that the autocorrelation is successfully eliminated from the residuals and incorporated into the final model. This allows the use of statistical inference.

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Student perception about working in rural United States/Canada after graduation: a study in an offshore Caribbean medical school

F1000Research ◽

10.12688/f1000research.5927.1 ◽

2014 ◽

Vol 3 ◽

pp. 301

Author(s):

P Ravi Shankar ◽

Arun K Dubey ◽

Atanu Nandy ◽

Burton L Herz ◽

Brian W Little

Keyword(s):

United States ◽

Rural Areas ◽

Professional Growth ◽

Student Perception ◽

Medical Schools ◽

The United States ◽

Rural Practice ◽

Growth Potential ◽

Cultural Issues ◽

The Government

Introduction: Rural residents of the United States (US) and Canada face problems in accessing healthcare. International medical graduates (IMGs) play an important role in delivering rural healthcare. IMGs from Caribbean medical schools have the highest proportion of physicians in primary care. Xavier University School of Medicines admits students from the US, Canada and other countries to the undergraduate medical (MD) course and also offers a premedical program. The present study was conducted to obtain student perception about working in rural US/Canada after graduation. Methods: The study was conducted among premedical and preclinical undergraduate medical (MD) students during October 2014. The questionnaire used was modified from a previous study. Semester of study, gender, nationality, place of residence and occupation of parents were noted. Information about whether students plan to work in rural US/Canada after graduation, possible reasons why doctors are reluctant to work in rural areas, how the government can encourage rural practice, possible problems respondents anticipate while working in rural areas were among the topics studied.Results: Ninety nine of the 108 students (91.7%) participated. Forty respondents were in favor of working in rural US/Canada after graduation. Respondents mentioned good housing, regular electricity, water supply, telecommunication facilities, and schools for education of children as important conditions to be fulfilled. The government should provide higher salaries to rural doctors, help with loan repayment, and provide opportunities for professional growth. Potential problems mentioned were difficulty in being accepted by the rural community, problems in convincing patients to follow medical advice, lack of exposure to rural life among the respondents, and cultural issues.Conclusions: About 40% of respondents would consider working in rural US/Canada. Conditions required to be fulfilled have been mentioned above. Graduates from Caribbean medical schools have a role in addressing rural physician shortage. Similar studies in other offshore Caribbean medical schools are required as Caribbean IMGs make an important contribution to the rural US and Canadian health workforce.

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The Shock Waves of the Haitian Revolution

Slave No More ◽

10.5149/northcarolina/9781469649634.003.0008 ◽

2019 ◽

pp. 164-196

Author(s):

Aline Helg

Keyword(s):

United States ◽

Great Britain ◽

Shock Waves ◽

Large Scale ◽

The United States ◽

Haitian Revolution ◽

Saint Domingue ◽

Northern United States ◽

The Government ◽

The Haitian Revolution

This chapter explores the shock waves caused by the Haitian Revolution and the massive slave insurrection that took both the Americas and Europe by surprise. Despite the rarity of large-scale revolts after 1794, the Saint Domingue insurrection did have a lasting impact on the slaves. The greatest lesson they retained from Haiti was that the institution of slavery was neither unchangeable nor invincible. Amid the troubled backdrop of the age of revolutions, many attentively followed the legal changes upsetting their owners, like the Spanish Códigno Negro, the French abolition of slavery, gradual emancipation laws in the northern United States, and the ban of the slave trade by Great Britain and the United States. Furthermore, after 1794, protests during which slaves claimed freedom they believed to have been decreed by the king or the government, but hidden by their masters, multiplied.

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Biomass losses resulting from insect and disease invasions in US forests

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1820601116 ◽

2019 ◽

Vol 116 (35) ◽

pp. 17371-17376 ◽

Cited By ~ 19

Author(s):

Songlin Fei ◽

Randall S. Morin ◽

Christopher M. Oswalt ◽

Andrew M. Liebhold

Keyword(s):

United States ◽

Tree Mortality ◽

Forest Biomass ◽

The United States ◽

Ecological Impacts ◽

Pest Species ◽

Forest Pests ◽

Ecosystem Impacts ◽

Biomass Loss ◽

Future Loss

Worldwide, forests are increasingly affected by nonnative insects and diseases, some of which cause substantial tree mortality. Forests in the United States have been invaded by a particularly large number (>450) of tree-feeding pest species. While information exists about the ecological impacts of certain pests, region-wide assessments of the composite ecosystem impacts of all species are limited. Here we analyze 92,978 forest plots distributed across the conterminous United States to estimate biomass loss associated with elevated mortality rates caused by the 15 most damaging nonnative forest pests. We find that these species combined caused an additional (i.e., above background levels) tree mortality rate of 5.53 TgC per year. Compensation, in the form of increased growth and recruitment of nonhost species, was not detectable when measured across entire invaded ranges but does occur several decades following pest invasions. In addition, 41.1% of the total live forest biomass in the conterminous United States is at risk of future loss from these 15 pests. These results indicate that forest pest invasions, driven primarily by globalization, represent a huge risk to US forests and have significant impacts on carbon dynamics.

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