Green lumber grade yields from black cherry and red maple factory grade logs sawed at band and circular mills

1989 ◽  
Vol 19 (11) ◽  
pp. 1436-1444 ◽  
Author(s):  
Daniel A. Yaussy

Multivariate regression models were developed to predict green board-foot yields (1 board ft. = 2.360 dm3) for the standard factory lumber grades processed from black cherry (Prunusserotina Ehrh.) and red maple (Acerrubrum L.) factory grade logs sawed at band and circular sawmills. The models use log measurements of grade, scaling diameter, length, and proportion of scaling defect. They can be used in computer programs related to sawmill simulations, economic modeling, or log-yard inventory systems.

1987 ◽  
Vol 4 (3) ◽  
pp. 154-157
Author(s):  
Daniel A. Yaussy

Abstract Multivariate regression models were developed to predict green board-foot yields for the common factory-lumber grades processed from sugar maple and basswood factory grade logs. These models use the standard log measurements of grade, scaling diameter, log length, and proportion of scaling defect. Any combination of lumber grades (such as 1 Common and Better) or total yield can be predicted with these models. The coefficients presented here can be used in computer programs related to sawmill simulations, economic modeling, or log-yard inventory systems. North. J. Appl. For. 4:154-157, Sept. 1987.


1990 ◽  
Vol 20 (9) ◽  
pp. 1479-1484 ◽  
Author(s):  
F. A. Bazzaz ◽  
J. S. Coleman ◽  
S. R. Morse

We examined how elevated CO2 affected the growth of seven co-occurring tree species: American beech (Fagusgrandifolia Ehrh.), paper birch (Betulapapyrifera Marsh.), black cherry (Prunusserotina Ehrh.), white pine (Pinusstrobus L.), red maple (Acerrubrum L.), sugar maple (Acersaccharum Marsh.), and eastern hemlock (Tsugacanadensis (L.) Carr). We also tested whether the degree of shade tolerance of species and the age of seedlings affected plant responses to enhanced CO2 levels. Seedlings that were at least 1 year old, for all species except beech, were removed while dormant from Harvard Forest, Petersham, Massachusetts. Seeds of red maple and paper birch were obtained from parent trees at Harvard Forest, and seeds of American beech were obtained from a population of beeches in Nova Scotia. Seedlings and transplants were grown in one of four plant growth chambers for 60 d (beech, paper birch, red maple, black cherry) or 100 d (white pine, hemlock, sugar maple) under CO2 levels of 400 or 700 μL•L−1. Plants were then harvested for biomass and growth determinations. The results showed that the biomass of beech, paper birch, black cherry, sugar maple, and hemlock significantly increased in elevated CO2, but the biomass of red maple and white pine only marginally increased in these conditions. Furthermore, there were large differences in the magnitude of growth enhancement by increased levels of CO2 between species, so it seems reasonable to predict that one consequence of rising levels of CO2 may be to increase the competitive ability of some species relative to others. Additionally, the three species exhibiting the largest increase in growth with increased CO2 concentrations were the shade-tolerant species (i.e., beech, sugar maple, and hemlock). Thus, elevated CO2 levels may enhance the growth of relatively shade-tolerant forest trees to a greater extent than growth of shade-intolerant trees, at least under the light and nutrient conditions of this experiment. We found no evidence to suggest that the age of tree seedlings greatly affected their response to elevated CO2 concentrations.


2008 ◽  
Vol 99 (9) ◽  
pp. 1841-1859 ◽  
Author(s):  
Lixing Zhu ◽  
Ruoqing Zhu ◽  
Song Song

Author(s):  
Paul D. Rosero-Montalvo ◽  
Jose Pijal-Rojas ◽  
Carlos Vasquez-Ayala ◽  
Edgar Maya ◽  
Carlos Pupiales ◽  
...  

2021 ◽  
Author(s):  
C Longchamps ◽  
S Ducarroz ◽  
L Crouzet ◽  
N. Vignier ◽  
L. Pourtau ◽  
...  

AbstractCOVID-19 vaccine hesitancy is frequent and can constitute a barrier to the dissemination of vaccines once they are available. Unequal access to vaccines may also contribute to socioeconomic inequalities with regard to COVID-19. We studied vaccine hesitancy among persons living in homeless shelters in France between May and June 2020 (n=235). Overall, 40.9% of study participants reported vaccine hesitancy, which is comparable to general population trends in France. In multivariate regression models, factors associated with vaccine hesitancy are: being a woman (OR=2.55; 95% CI 1.40-4.74), living with a partner (OR=2.48, 95% CI 1.17-5.41), no legal residence in France (OR=0.51, 95% CI 0.27-0.92), and health literacy (OR=0.38, 95% CI 0.21, 0.68). Our results suggest that trends in vaccine hesitancy and associated factors are similar among homeless persons as in the general population. Dissemination of information on vaccine risks and benefits needs to be adapted to persons who experience severe disadvantage.


1999 ◽  
Vol 51 (4) ◽  
pp. 547-572 ◽  
Author(s):  
Andrew Reynolds

This article reports the results of a survey of women in legislatures and executives around the world as they were constituted in 1998 (N = 180). The chief hypotheses regarding the factors hindering or facilitating women's access to political representation were tested by multivariate regression models. The regression models juxtaposed a cocktail of institutional, political, cultural, and socioeconomic variables with the following dependent variables: (1) the percentage of MPs who are women and (2) the percentage of cabinet ministers who are women.A number, although not all, of the cited hypotheses were statistically confirmed and more finely quantified. The socioeconomic development of women in society has an effect on the number of women in parliament but not in the cabinet. A country's length of experience with multipartyism and women's enfranchisement correlates with both the legislative and the executive percentage. Certain electoral systems are more women friendly than others. The ideological nature of the party system affects the number of women elected and chosen for cabinet posts. And last, the state's dominant religion, taken as a proxy for culture, also statistically relates to the number of women who will make it to high political office. However, other long-held hypotheses were not proved. The degree of democracy is not a good indicator of the percentage of women who will make it into the legislature or the cabinet, nor is the dichotomy between a presidential or parliamentary system.


2018 ◽  
Vol 46 (9) ◽  
pp. 2096-2102 ◽  
Author(s):  
Yoshiharu Shimozono ◽  
Johanna C.E. Donders ◽  
Youichi Yasui ◽  
Eoghan T. Hurley ◽  
Timothy W. Deyer ◽  
...  

Background: Uncontained-type osteochondral lesions of the talus (OLTs) have been shown to have inferior clinical outcomes after treatment with bone marrow stimulation. While autologous osteochondral transplantation (AOT) is indicated for larger lesions, no study has reported on the prognostic significance of the containment of OLTs treated with the AOT procedure. Purpose: To clarify the effect of the containment of OLTs on clinical and radiological outcomes in patients who underwent AOT for OLTs. Study Design: Case control study; Level of evidence, 3. Methods: A retrospective cohort study comparing patients with contained-type and uncontained-type OLTs was undertaken to include all patients who underwent AOT for the treatment of OLTs between 2006 and 2014. Analyses were performed by grouping the patients according to the containment type. Clinical outcomes were evaluated using the Foot and Ankle Outcome Score (FAOS) and the 12-Item Short Form Health Survey (SF-12) preoperatively and at final follow-up. Magnetic resonance imaging (MRI) at 2 years’ follow-up was evaluated with the modified magnetic resonance observation of cartilage repair tissue (MOCART) score. Multivariate regression models were used to evaluate factors affecting postoperative FAOS, SF-12, and MOCART scores. Results: Ninety-four patients were included: 31 patients with a contained-type OLT and 63 patients with an uncontained-type OLT. The median patient age was 34 years (interquartile range [IQR], 28-48 years) in the contained-type group and 36 years (IQR, 27-46 years) in the uncontained-type group. The median follow-up time was 45 months (IQR, 38-63 months) in the contained-type group and 52 months (IQR, 40-66 months) in the uncontained-type group. The median FAOS and SF-12 scores improved significantly after surgery in both contained-type and uncontained-type lesions ( P < .001). The median postoperative FAOS score of patients with contained-type OLTs was higher than that of patients with uncontained-type OLTs (91.7 vs 85.0, respectively; P = .009), but no significant differences were found between the contained-type and uncontained-type groups for postoperative SF-12 and MOCART scores. The multivariate regression models showed that patients with contained-type OLTs had an approximately 10-point better score on the FAOS compared with patients with uncontained-type OLTs ( P = .006). There was a nonsignificant trend for the rate of cystic occurrence in uncontained-type OLTs to be higher than that of contained-type OLTs (55.6% vs 38.7%, respectively; P = .125). Conclusion: Patients with contained-type OLTs experienced better clinical outcomes than those with uncontained-type OLTs after AOT for the treatment of OLTs. However, the AOT procedure still provided good clinical and MRI outcomes in both contained-type and uncontained-type OLTs at midterm follow-up.


1988 ◽  
Vol 12 (1) ◽  
pp. 23-27 ◽  
Author(s):  
Neil I. Lamson

Abstract In northern West Virginia, 7-year-old American basswood (Tilia americana L.) and 12-year-old red maple (Acer rubrum L.), black cherry (Prunus serotina Ehrh.), and northern red oak (Quercus rubra L.) stump sprout clumps received one of four treatments: unthinned control; thinned to the best one or two codominant sprouts per clump; branch pruned up to 75% of total height; or thinned plus pruned. Analysis of 10-year growth data showed that height growth was not affected by any of the treatments. For all species, pruning slightly increased the length of clear stem and decreased periodic diameter growth. Thinning increased survival of basswood, red oak, and red maple crop stems. Thinning increased the 10-year diameter growth by 0.1 to 0.8 in. Recommendations for thinning 10- to 20-year-old sprout clumps are presented. Pruning is not recommended. In order to maintain maximum diameter growth, thinning individual sprout clumps should be followed by stand crop tree release in about 10 years. South. J. Appl. For. 12(1):23-27.


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