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Reaction between deposited Ca layers and the Si(111) substrate has been studied by metastable-induced electron spectroscopy (MIES) and low-energy electron diffraction (LEED). When a Ca-deposited (about 1ML) Si(111) surface was annealed at temperatures in the range 470-570 K, the MIES spectrum showed a peak, named P s , at a binding energy of about 7 eV which is assigned to be an isolated Si3s state. By referring electronic structure calculations for the bulk Ca-silicides, we confirmed that a solid-phase reaction at the Ca/Si interface to induce Ca 2 Si-like phases takes place at rather low annealing temperatures around 570 K. When Ca-covered (about 0.6 ML) Si(111) surfaces were annealed at temperatures in the range 770-870 K, the LEED showed 2 × 1, 5 × 1 and quasi-3 × 2 reconstructions, depending on the temperature. We obtained MIES spectra from these surfaces involving spectral features which reflect local atomic structures of those Ca+Si surface phases. Correlations between the local atomic structure and the electronic structure probed by the MIES are discussed.

BACKGROUND: Complete mesocolic excision with central vascular ligation is a standard method for colon cancer. However, there is no consensus on its procedure, especially for cancer in the splenic flexure of the transverse colon. This is because various types of variational arteries are distributed to the region, and their running course below and near the pancreas leads to difficulty in ligating the artery. OBJECTIVE: This study aimed to clarify the arterial distribution to the SF of the transverse colon using cadavers. DESIGN: The arteries in the transverse mesocolon distributed to the colon were dissected in cadavers, and their route was quantitatively visualized using drawing software. SETTINGS: This study was conducted at the Department of Anatomy, Tokyo Medical University. PATIENTS: Sixty cadavers donated to Tokyo Medical University in 2017–2021 were used. MAIN OUTCOME MEASURES: The arterial courses to the splenic flexure of the transverse colon in the mesocolon and their patterns were evaluated. RESULTS: We found 34 variational arteries distributed to the splenic flexure of the transverse colon. Most originated from the superior mesenteric artery and middle colic artery, with their typical course below the pancreas. We identified another arterial course, crossing the mesocolon away from the pancreas toward the splenic flexure of the transverse colon. Furthermore, the origin of these arteries was not behind the pancreas and can be found in the caudal region of the pancreas. LIMITATIONS: We cannot discuss how the arteries within the transverse mesocolon are observed by computed tomography examination. CONCLUSIONS: This study showed two types of arterial courses (below the pancreas and within the mesocolon) toward the splenic flexure of the transverse colon for the first time. In the latter case, the complete mesocolic excision with central vascular ligation is likely performed more easily than in the former.