An efficient system of micropropagation via somatic embryogenesis from root-derived callus was established in

Arabica coffee (Coffea arabica L.). Twenty-six callus lines were induced on MS (Murashige and Skoog, 1962)

medium supplemented with combinations of NAA (0, 0.1, 0.5, 1 and 2 mg/L) plus BA (0, 1 and 2 mg/L), or 2,4-D

(0, 0.1, 0.5, 1 and 2 mg/L) plus TDZ (0, 1 and 2 mg/L). Subsequently, two types of somatic embryos were obtained

from callus cultures and named S-type and I-type embryos. The S-type embryos were obtained from an 18-monthold

callus line which was induced and maintained at 2 mg/L TDZ and 0.1 mg/L 2,4-D near the end of each period

of the subculture. These embryos have a developmental barrier, which did not pass through the torpedo stage

and could be overcome by a supplement of 2 or 5 mg/L BA. The I-type embryos were induced from 3-month-old

callus when transferred onto induction media, i.e., MS supplemented with TDZ (2 and 5 mg/L) plus 2,4-D (0 and

0.1 mg/L). The significantly highest response, i.e., 13.3 embryos per callus clump was obtained at 2 mg/L TDZ.

In this study, the results reveal that TDZ has a crucial effect on embryogenic callus induction, proliferation and

subsequent somatic embryogenesis.

This paper presents a numerical investigation into the high strength steel (HSS) welded Isection overall buckling performance with respect to the major axis under combined axial compression and bending. The validation of FE models compared with the existing test data to verify the appropriateness of the element division and boundary condition was firstly conducted. In line with the FE arrangement verified, separate 890 numerical models, covering a broader range of eight steel grades (460 MPa, 500 MPa, 550 MPa, 620 MPa, 690 MPa, 800 MPa, 890 MPa and 960 MPa), different overall slenderness and various eccentricities were designated. Subsequently, the comparison of the resistance prediction codified design rules in EN1993-1-1, ANSI/AISC 360-10 and GB50017-2017 was preferentially operated, by the instrumentality of the normalized axial compression-bending moment curves. The results graphically revealed that, the provision given in ANSI/AISC 360-10 concerned in the present work was the most loose, whereas, the corresponding content set out in EN1993-1-1 and GB50017-2017 was relatively on the safe side. Taking account of the FE results, the conservative shortcomings of the considered rules in EN1993-1-1 and GB50017-2017 were further highlighted. Especially, the disparity of EN1993-1-1 and numerical results was higher to 27%, from the perspective of a definition given in the present work. In contrast, the provision in ANSI/AISC 360-10 yielded a relatively accurate prediction, on average. Based on the numerical program, an alternative formula for the HSS welded I-section beam-columns with a general expression form was sought, which intimately reflected the effect of overall slenderness.