Background: Previously, we conducted a randomized controlled trial (JCOG0404) for stage II/III colon cancer patients and reported that the long‐term survival after open surgery (OP) and laparoscopic surgery (LAP) were almost identical; however, JCOG0404 suggested that survival of patients after LAP with tumors located in the rectosigmoid colon, cT4 or cN2 tumors, and high body mass index (BMI) might be unfavorable.Aim: To identify the patient subgroups associated with poor long‐term survival in the LAP arm compared with the OP arm.Methods: Patients aged 20–75, clinical T3 or deeper lesion without involvement of other organs, clinical N0‐2 and M0 were included. The patients with pathological stage IV and R2 resection were excluded from the current analysis. In each subgroup, the hazard ratio for LAP (vs. OP) in overall survival (OS) from surgery was estimated using a multivariable Cox regression model adjusted for the clinical and pathological factors.Results: In total, 1025 patients (OP, 511 and LAP, 514) were included in the current analysis. Adjusted hazards ratios for OS of patients with high BMI (>25 kg/m²), pT4, and pN2 in LAP were 3.37 (95% confidence interval [CI], 1.24–9.19), 1.33 (0.73–2.41), and 1.74 (0.76–3.97), respectively. In contrast, that of rectosigmoid colon tumors was 0.98 (0.46–2.09).Conclusions: Although LAP is an acceptable optional treatment for stage II/III colon cancer, the present subgroup analysis suggests that high BMI (>25 kg/m²), pT4, and pN2 except for RS were factors associated with unfavorable long‐term outcomes of LAP in patients with colon cancer who underwent curative resection. (JCOG 0404: NCT00147134/UMIN‐CTR: C000000105.)

The pure rotational transitions of the protonated hydrogen cyanide ion, HCNH⁺, and its isotopic species, HCND⁺ and DCND⁺, were measured in the 107-482 GHz region with a source-modulated microwave spectrometer. The ions were generated in a cell with a magnetically confined DC-glow discharge of HCN and/or DCN. The rotational constant B₀ and the centrifugal distortion constant D₀ for each ion were precisely determined by a least-squares fitting to the observed spectral lines. The observed rotational transition frequencies by laboratory spectroscopy and the predicted ones are accurate to about 30-40 kHz and are useful as rest frequencies for astronomical searches of HCNH⁺ and HCND⁺.

The pure rotational spectrum of the AsH2 radical in its B12 ground electronic state was observed for the first time by microwave spectroscopy. The AsH2 radical was generated in a free-space cell by dc-glow discharge of a mixture of H2 and O2 gases over arsenic powder. Fifty-five fine and hyperfine components of six rotational transitions were measured in the frequency region of 304–374 GHz, and were analyzed by least-squares methods. Molecular constants, including the rotational constants, the centrifugal distortion constants, the spin-rotation coupling constant incorporating the centrifugal distortion term, and the hyperfine coupling constants associated with the arsenic and hydrogen nuclei, were precisely determined. The bonding in AsH2 was discussed on the basis of the hyperfine coupling constants, first determined in the present study.

The pure rotational transition of the NF radical in the second electronically excited state, ${\mathrm{b\hspace{0.17em}}}^1{\Sigma }^{+},$ was detected by microwave spectroscopy. The NF radical was generated by dc-discharge through a mixture of ${\mathrm{NF}}_{\mathrm{3}}$ and ${\mathrm{H}}_{\mathrm{2}}$ at around 90 K. Six rotational transitions for $\text{v=0}$ and four for $\text{v=1}$ were observed in the 73–442 GHz region. In addition to the rotational and centrifugal distortion constants, the quadrupole coupling constant of the nitrogen nucleus of $\mathrm{NF}{\mathrm{(b\hspace{0.17em}}}^1{\Sigma }^{+})$ was determined for the first time from the lowest two transitions of NF in the $\text{v=0}$ level. The spectrum of $\mathrm{NF}{\mathrm{(a\hspace{0.17em}}}^1\mathrm{\Delta )}$ in the first vibrational excited state was also observed in order to derive highly accurate potential parameters for comparison with the data of $\mathrm{NF}{\mathrm{(X\hspace{0.17em}}}^3{\Sigma }^{-}{\mathrm{,b\hspace{0.17em}}}^1{\Sigma }^{+}\mathrm{).}$