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The low-lying dipole strength in the $^{90,94}$Zr nuclei was investigated via (p,p′γ) at 80 MeV and (α,α′γ) at 130 MeV. The experiments, made at RCNP, used the magnetic spectrometer Grand Raiden for the scattered particles and the array CAGRA with HPGe detectors for the γ-decay. For $^{94}$Zr these are the first data for both reactions and for $^{90}$Zr these are the first data with (p,p′γ) and the first ones at high resolution for (α,α′γ). The comparison of the present results for the two nuclei with existing (γ,γ′) data shows that both nuclear probes produce an excitation pattern different than that of the electromagnetic probes.DWBA calculations were made using form factors deduced from transition densities, based on RPA calculations, characterized by a strong neutron component at the nuclear surface. A combined analysis of the two reactions was performed for the first time to investigate the isoscalar character of the 1$^{−}$ states in $^{90,94}$Zr. The (p,p′γ) cross section was calculated using values for the isoscalar electric dipole energy-weighted sum rule (E1 ISEWSR) obtained from the (α,α′γ) data. The isoscalar strength for $^{90}$Zr was found to exhaust 20 ± 2.5% of the EWSR in the energy range up to 12 MeV. In case of $^{94}$Zr, a strength of 9 ± 1.1% of the EWSR was found in the range up to 8.5 MeV.Although an overall general description was obtained in the studied energy intervals, not all proton cross sections were well reproduced using the isoscalar strength from (α,α′γ). This might suggest mixing of isoscalar and isovector components and that this mixing and the degree of collectivity are not the same for all the 1$^{−}$ states below the particle binding energy.

Colorectal cancer is a leading cancer worldwide and in Vietnam. Adenomas (adenomatous polyps) is an important precursor of colorectal cancer. There is currently no study to determine the modifiable risk factors for colorectal adenomas, including body mass index (BMI) in Vietnam. We conducted an individually matched case-control study of 1149 colorectal adenomas and 1145 controls in a large-scale colorectal screening program involving 103 542 individuals aged 40-75 years old in Hanoi, Vietnam. Conditional logistic regression was used to evaluate the association between BMI and colorectal adenomas prevalence, after controlling for potential confounders. Overall, comparing to normal weight (ie, 18.5-22.9kg/m2), underweight (ie, BMI < 18.5) was associated with a non-statistically significant increased prevalence of colorectal adenomas (odd ratio [OR]=1.29 and 95% confident interval [CI]: 0.88-1.87). This association became significant among male (OR=1.98, 95% CI: 1.20-3.27), male who were ever smokers (OR=2.59, 95% CI: 1.33-5.03), nonregular exercise (OR=2.44, 95% CI: 1.26-4.73) and individuals with cardiometabolic disorders (OR=3.46, 95% CI: 1.19-10.00). The association between underweight and colorectal adenomas did not vary by smoking status, drinking status, family history of cancer, adenomas types or cardiometabolic disorders. No association was observed among obese individuals (BMI ≥ 25). In the population with low prevalence of obesity, we found that the association between BMI and colorectal adenomas followed a reversed J-shape that underweight was associated with increased prevalence. Further studies are, therefore, warranted to replicate our results and to investigate the biologic mechanism the effect of underweight on colorectal adenomas prevalence.