Some physical and mechanical characterization of Tunisian planted Eucalytus loxophleba and Eucalyptus salmonophloia woods

After the independence in 1957 and with the support of the FAO117, Eucalyptus species were planted in Tunisia in different arboreta throughout the country for close observation and adaptation to climate and soil. The objective of this study is to evaluate the physical and mechanical properties of two species planted in marginal area in Sousse (arboretum El Hanya) in the east of Tunisia (Eucalytus loxophleba and Eucalyptus salmonophloia). The moisture content, specific gravity and volumetric shrinkage were measured. The Mechanical tests were performed to evaluate the hardness, the static bending and the resistance to compression parallel to fiber direction. Preliminary results showed that Eucalytusloxophleba and Eucalyptus salmonophloia have a low dimensional stability. During the drying period, woods showed signs of collapses. On the other hand, both species were highly resistant to compression strength while they were lower on the static bending. Eucalytus loxophleba and Eucalyptus salmonophloia characteristics established within this study were similar to other Eucalyptus species from Tunisia, Morocco, Australia and Brazil. This wood may be used in furniture, structural material and/or biomass energy. (Résumé d'auteur

Inducible expression of DTA in nestin-lineage stem/progenitor cells decreases the number of Ki67+ and DCX+ cells 12 days (d) post-tamoxifen (TAM), but DCX+ cell number is normalized 30d post-TAM.

<p><b>(A)</b> Experimental design of immunohistochemical study. TAM was administered to 5–6 week-old control or Cre+DTA+ mice for 5 consecutive days, and brains were collected 12d and 30d post-TAM. <b>(B)</b> Representative photomicrographs of the dentate gyrus from control and Cre+DTA+ mice 12d post-TAM stained with an antibody against Ki67. Scale bar = 200 um <b>(B,</b> applies to <b>B, D). (C)</b> Stereological quantification of Ki67+ cell number in the DG granule cell layer (GCL) 12d (control N = 5, Cre+DTA+ N = 4) and 30d (control N = 6, Cre+DTA+ N = 9) post-TAM. <b>(D)</b> Representative photomicrographs of the DG from control and Cre+DTA+ mice 12d post-TAM stained with antibody against DCX. <b>(E)</b> Stereological quantification of DCX+ cells in the DG GCL 12d (control N = 4, Cre+DTA+ N = 5) and 30d (control N = 6, Cre+DTA+ N = 7) post-TAM. <b>(F)</b> High magnification images of the DG from control and Cre+DTA+ mice 12d post-TAM stained with an antibody against DCX+. Scale bar = 50um. <b>(G)</b> Stereological quantification of postmitotic DCX+ cells in the DG GCL 12d (control N = 4, Cre+DTA+ N = 5) and 30d (control N = 6, Cre+DTA+ N = 7). Data are mean±SEM,.**p<0.01, *p<0.05 by unpaired, two-tailed Student’s t-test.</p

Relative to control mice, stress induced anxiety-like and depressive-like behavior are evident in Cre+DTA+ mice tested less than–but not more than– 4 weeks post-TAM.

<p><b>(A, B)</b> Latency to feed in the novelty induced hypophagia test (NIH) in control vs. Cre+DTA+ mice at short (<b>A,</b> Group 1, control N = 31, Cre+DTA+ N = 10) and long (<b>B,</b> Group 2, control N = 39, Cre+DTA+ N = 16) TAM-behavior intervals. <b>(C, D)</b> Total immobility time in the tail suspension test (TST) in control vs. Cre+DTA+ mice at short (<b>C,</b> Group 1, control N = 27, Cre+DTA+ N = 9) and long (<b>D,</b> Group 2, control N = 38, Cre+DTA+ N = 15) TAM-behavior intervals. <b>(E, F)</b> Interaction time during juvenile interaction training and test sessions in control vs. Cre+DTA+ mice at short (<b>E,</b> Group 1, control N = 30, Cre+DTA+ N = 9) and long (<b>F,</b> Group 2, control N = 40, Cre+DTA+ N = 17) TAM-beh intervals. Data = mean±SEM. *p<0.05, unpaired two-tailed Student’s t-test (A-D). ^<i>b</i>p<0.01,^<i>c</i>p<0.005, ^<i>d</i>p<0.0001, two-way ANOVA with repeated measures and Bonferroni posthoc.</p

Cre+DTA+ mice tested less than or more than 4 weeks post-TAM show similar levels of locomotion and the absence of baseline anxiety-related behaviors.

<p><b>(A, B)</b> Locomotor activity (LM) in both short (<b>A,</b> Group 1, control N = 8, Cre+DTA+ N = 5) and long (<b>B,</b> Group 2, control N = 33, Cre+DTA+ N = 13) TAM-beh interval groups. Insets <b>A, B</b>: total beam breaks over 2 hr. Main panels <b>A, B</b>: beam breaks over 2 hr presented in 5 min bins. X axis * = main effect of time. Posthoc analysis (Bonferroni) revealed all points in main panels were significantly different than the initial locomotor activity data point. However, individual data point asterisks are omitted for clarity, as there was no main effect of genotype or interaction of time X genotype for either Group 1 or Group 2. <b>(C-F)</b> Time spent in the center <b>(C, E)</b> and periphery <b>(D, F)</b> during an open field test (OF) in short (<b>C-D,</b> Group 1, control N = 30, Cre+DTA+ N = 9) and long (<b>E-F,</b> Group 2, control N = 42, Cre+DTA+ N = 17) TAM-beh interval groups. <b>(G-J)</b> Number of transitions between light and dark chambers <b>(G, I)</b> and latency to enter the dark chamber <b>(H, J)</b> in the light/dark test (L/D test) in both short (<b>G-H,</b> Group 1, control N = 30, Cre+DTA+ N = 9) and long (<b>H-I,</b> Group 2, control N = 38, Cre+DTA+ N = 17) TAM-beh groups. Data are mean±SEM. ^<i>d</i>p<0.0001, two-way ANOVA with repeated measures and Bonferroni posthoc <b>(A, B)</b>. *p<0.05, unpaired two-tailed Student’s t-test (<b>insets A, B,</b> and <b>C-H</b>).</p

Experimental design of behavioral study.

<p>TAM was administered to 5–6 week-old control or Cre+DTA+ mice for 5 consecutive days. Behavioral testing began 12d (Group 1) or 33d post-TAM (Group 2), and continued as indicated through day 27 (Group 1, TAM-behavioral [TAM-beh] interval less than 4 weeks) or day 52 (Group 2, TAM-beh interval more than 4 weeks) post-TAM. Both groups were examined in the open field test (OF), locomotor test (LM), novelty induced hypophagia (NIH), light/dark test (L/D), juvenile social interaction test (JI), and tail suspension test (TST). Specifically for Groups 1 and Groups 2, OF was performed 12d or 33d post-TAM, LM 15d or 37d post-TAM, NIH 17-19d or 39-41d post-TAM, L/D 21d or 43d post-TAM, JI 22-25d or 44-47d post-TAM, and TST 27d or 52d post-TAM.</p