scholarly journals The Percentage of Trees Bearing Cones as a Predictor for Annual Longleaf Pine Cone Production

2021 ◽  
Vol 4 ◽  
Author(s):  
Thomas Patterson

The U.S. Forest Service has monitored longleaf pine cone production at sites throughout the southeastern United States for over 60 years. Data from the multi-decadal surveys have supported our understanding of the variability of stand-level cone production as it relates to environmental and ecological processes, and more broadly, how longleaf pine operates as a masting species. Cones from longleaf pine are counted each spring using visual surveys that follow a standard protocol. Rapid mast assessments have been proposed in the literature as an alternative to traditional methods, yet these approaches have not been examined for longleaf pine. In this study, I compared average cone production (using the traditional method) to the percentage of trees bearing cones (rapid assessment) to understand the relationship between these two mast measurements. I examined 29 years of data from 18 cone-monitoring sites containing 234 trees. Using simple linear models, I discovered the percentage of trees bearing cones explained 58–94% of the variance in log-average cone production across all sites. One-way ANOVA analysis revealed cone crops required for successful regeneration (25 + cones per tree) occurred when the percentage of trees bearing cones exceeded 90%, and the results from this study underscore the utility of a simple 90% threshold when determining a successful cone crop. While traditional cone-count methods should not be abandoned, I advocate for the use of rapid cone-crop assessments when a proxy approach is suitable.

Author(s):  
Mehmet Sarıışık ◽  
Hasan Önal Şeyhanlıoğlu

In this study, it is aimed to examine the relationship between personality traits and career planning trends of tourism management employees. The data required for the study were obtained from a total of 391 employees in five and four-star five-city hotels in Ankara. The collected data were analyzed by quantitative methods to test the relationship between variables. First, the correlation coefficients between the sub-dimensions of the scales were calculated. Then, t-test and variance (One-way Anova) analysis were used to determine possible differences between career planning dimensions and demographic characteristics. As a result of the study, it was found that there was a positive and significant relationship between extrovert personality type and career planning while a negative significant relationship was found between neurotic personality type and career planning.


2013 ◽  
Vol 361-363 ◽  
pp. 2152-2155
Author(s):  
Yu Wu ◽  
Shun Ying Zhu ◽  
Hong Wang ◽  
Fei Yao ◽  
Huai Zhong Zhu

This paper analyzed the relationship between the gap selection and the types of oncoming vehicle in the process of pedestrians crossing the road. The oncoming vehicles were divided into large and small vehicle; six groups of pedestrians were recorded, young-male, mid-aged-male, old-male, young-female, mid-aged-female and old-female. The accepted gaps were recorded and analyzed using one-way ANOVA analysis. The results showed that, oncoming vehicles type had significant impact upon gap selection of pedestrians. A large oncoming vehicle had a shorter selected gap than a small oncoming vehicle. It is concluded that pedestrians have a smaller perceived velocity and overestimate the gap, large oncoming vehicle arrive conflict point. However, the overestimated gap was likely not safe to crossing the road. So, at no signal control intersection, a strict speed limit was necessary for large vehicle.


2021 ◽  
Vol 10 (6) ◽  
pp. 1211
Author(s):  
Li-Te Lin ◽  
Kuan-Hao Tsui

The relationship between serum dehydroepiandrosterone sulphate (DHEA-S) and anti-Mullerian hormone (AMH) levels has not been fully established. Therefore, we performed a large-scale cross-sectional study to investigate the association between serum DHEA-S and AMH levels. The study included a total of 2155 infertile women aged 20 to 46 years who were divided into four quartile groups (Q1 to Q4) based on serum DHEA-S levels. We found that there was a weak positive association between serum DHEA-S and AMH levels in infertile women (r = 0.190, p < 0.001). After adjusting for potential confounders, serum DHEA-S levels positively correlated with serum AMH levels in infertile women (β = 0.103, p < 0.001). Infertile women in the highest DHEA-S quartile category (Q4) showed significantly higher serum AMH levels (p < 0.001) compared with women in the lowest DHEA-S quartile category (Q1). The serum AMH levels significantly increased across increasing DHEA-S quartile categories in infertile women (p = 0.014) using generalized linear models after adjustment for potential confounders. Our data show that serum DHEA-S levels are positively associated with serum AMH levels.


2021 ◽  
Vol 1 (1) ◽  
pp. 99-112
Author(s):  
Richard Larouche ◽  
Nimesh Patel ◽  
Jennifer L. Copeland

The role of infrastructure in encouraging transportation cycling in smaller cities with a low prevalence of cycling remains unclear. To investigate the relationship between the presence of infrastructure and transportation cycling in a small city (Lethbridge, AB, Canada), we interviewed 246 adults along a recently-constructed bicycle boulevard and two comparison streets with no recent changes in cycling infrastructure. One comparison street had a separate multi-use path and the other had no cycling infrastructure. Questions addressed time spent cycling in the past week and 2 years prior and potential socio-demographic and psychosocial correlates of cycling, including safety concerns. Finally, we asked participants what could be done to make cycling safer and more attractive. We examined predictors of cycling using gender-stratified generalized linear models. Women interviewed along the street with a separate path reported cycling more than women on the other streets. A more favorable attitude towards cycling and greater habit strength were associated with more cycling in both men and women. Qualitative data revealed generally positive views about the bicycle boulevard, a need for education about sharing the road and for better cycling infrastructure in general. Our results suggest that, even in smaller cities, cycling infrastructure may encourage cycling, especially among women.


Genetics ◽  
2000 ◽  
Vol 154 (4) ◽  
pp. 1851-1864 ◽  
Author(s):  
John A Woolliams ◽  
Piter Bijma

AbstractTractable forms of predicting rates of inbreeding (ΔF) in selected populations with general indices, nonrandom mating, and overlapping generations were developed, with the principal results assuming a period of equilibrium in the selection process. An existing theorem concerning the relationship between squared long-term genetic contributions and rates of inbreeding was extended to nonrandom mating and to overlapping generations. ΔF was shown to be ~¼(1 − ω) times the expected sum of squared lifetime contributions, where ω is the deviation from Hardy-Weinberg proportions. This relationship cannot be used for prediction since it is based upon observed quantities. Therefore, the relationship was further developed to express ΔF in terms of expected long-term contributions that are conditional on a set of selective advantages that relate the selection processes in two consecutive generations and are predictable quantities. With random mating, if selected family sizes are assumed to be independent Poisson variables then the expected long-term contribution could be substituted for the observed, providing ¼ (since ω = 0) was increased to ½. Established theory was used to provide a correction term to account for deviations from the Poisson assumptions. The equations were successfully applied, using simple linear models, to the problem of predicting ΔF with sib indices in discrete generations since previously published solutions had proved complex.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
David Gagnon ◽  
Abderrahim Zeribi ◽  
Élise Douard ◽  
Valérie Courchesne ◽  
Borja Rodríguez-Herreros ◽  
...  

Abstract Background Language delay is one of the major referral criteria for an autism evaluation. Once an autism spectrum diagnosis is established, the language prognosis is among the main parental concerns. Early language regression (ELR) is observed by 10–50% of parents but its relevance to late language level and socio-communicative ability is uncertain. This study aimed to establish the predictive value of ELR on the progression of language development and socio-communicative outcomes to guide clinicians in addressing parents’ concerns at the time of diagnosis. Methods We used socio-communicative, language, and cognitive data of 2,047 autism spectrum participants from the Simons Simplex Collection, aged 4–18 years (mean = 9 years; SD = 3.6). Cox proportional hazard and logistic regression models were used to evaluate the effect of ELR on language milestones and the probability of using complex and flexible language, as defined by the choice of ADOS module at enrollment. Linear models were then used to evaluate the relationship of ELR and non-verbal IQ with socio-communicative and language levels. Results ELR is associated with earlier language milestones but delayed attainment of fluent, complex, and flexible language. However, this language outcome can be expected for almost all autistic children without intellectual disability at 18 years of age. It is mostly influenced by non-verbal IQ, not ELR. The language and socio-communicative level of participants with flexible language, as measured by the Vineland and ADOS socio-communicative subscales, was not affected by ELR. Limitations This study is based on a relatively coarse measure of ultimate language level and relies on retrospective reporting of early language milestones and ELR. It does not prospectively document the age at which language catches up, the relationship between ELR and other behavioral areas of regression, nor the effects of intervention. Conclusions For autistic individuals with ELR and a normal level of non-verbal intelligence, language development follows a “bayonet shape” trajectory: early first words followed by regression, a plateau with limited progress, and then language catch up.


2020 ◽  
pp. 0192513X2094892
Author(s):  
Athira Amira Abd Rauf ◽  
Maizatul Akmar Ismail ◽  
Vimala Balakrishnan ◽  
Loh Sau Cheong ◽  
Novia Indriaty Admodisastro ◽  
...  

The parents of children with dyslexia often experience more parenting stress and depressive symptoms compared to other parents. Studies have shown that supporting and encouraging such parents help in reducing their frustrations, fear, anger, and low self-esteem towards their children. The purpose of this study was to identify and examine the different types of support needed by the parents of children with dyslexia and to explore the relationships between the required support with the parents’ marital status. Fifty questionnaires were distributed to the parents of children with dyslexia and analyzed. The findings showed that the type of support needed for parents of children with dyslexia could be grouped into social, peer-to-peer, financial, and government support. Furthermore, the analysis indicated that there were no significant differences between the social (p = 0.4014), peer-to-peer (p = 0.5020), and government (p = 0.7121) support with parents’ marital status. However, based on one-way ANOVA analysis, there was a significant difference found between the parents’ marital status and financial support (p = 0.0241). Accordingly, it is anticipated that the implication of this research could be used as a guide and a reference for supporting and encouraging parents of children with dyslexia and other learning disabilities.


Nutrients ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1780 ◽  
Author(s):  
Alwerdt ◽  
Patterson ◽  
Sliwinski

Sex hormone changes in adults are known to play a part in aging, including cognitive aging. Dietary intake of phytoestrogens can mimic estrogenic effects on brain function. Since sex hormones differ between genders, it is important to examine gender differences in the phytoestrogen–cognition association. Therefore, the goal of this study is to examine the relationship between urinary phytoestrogens and speed of processing (SOP) and the variation of the association between genders in older adults. Participants were drawn from the 1999–2002 National Health and Nutrition Examination Survey and included 354 individuals aged 65–85 years old. General linear models (GLMs) were used to test for significant gender differences in the relationship between phytoestrogens and SOP. Results from the GLMs showed significant gender differences in the relationship between genistein and SOP. Higher levels of genistein were associated with better SOP in women. This relationship was reversed in men: higher genistein levels were associated with worse performance. Results indicate that there are distinct gender differences in the relationship between genistein and SOP. These results emphasize the importance of considering gender differences when devising dietary and pharmacologic interventions that target phytoestrogens to improve brain health.


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