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Advancements in engineering construction have led to an increase in significant challenges with foundations and pavement infrastructure built on silty soil. Silty soils are created through the combination of mainly silt-sized particles (< 0.075 mm), typically with a small percentage of clay, and are vulnerable to frost. Biopolymers can possibly be an alternate solution for calcium-based stabilizers or be used as a co-additive. This study aimed to investigate the interaction of biopolymer-induced soil with multivalent ions via unconfined compressive strength to identify a potential stabilizer and appropriate dosages. For comparative analysis, biopolymers with different cations on silty soil strength were evaluated after curing for 7 days and 28 days. The results indicated that the biopolymer networks develop slowly; however, cross-linking the biopolymers with different cations enhanced their rate of stiffness and strength increase. This composite sample indicated a possible solution for partially replacing calcium-based stabilizers in frost-susceptible silty soil. 

We report the first observation of the radiative decay $D_{s0}^{*}(2317{)}^{+}\to D_s^{*+}\gamma$ with a statistical significance exceeding 10 standard deviations. The signal is observed in the continuum $e^{+}{e}^{-}\to c\overline{c}$ process, using combined data samples of $980.4{\mathrm{fb}}^{-1}$ from Belle and $427.9{\mathrm{fb}}^{-1}$ from Belle II, collected at the KEKB and SuperKEKB asymmetric-energy $e^{+}{e}^{-}$ colliders, respectively. The branching fraction ratio $\mathcal{B}\left[D_{s0}^{*}\right(2317{)}^{+}\to D_s^{*+}\gamma ]/\mathcal{B}[D_{s0}^{*}(2317{)}^{+}\to D_s^{+}{\pi }^0]$ is measured to be $[7.13\pm 0.70(\mathrm{stat})\pm 0.26(\mathrm{syst}\left)\right]\%$ . This result provides crucial discrimination between theoretical models of the $D_{s0}^{*}(2317{)}^{+}$ structure. 

Using a data sample of $427.9{\mathrm{fb}}^{-1}$ collected by the Belle II detector at or near the $\mathrm{\Upsilon }\left(4S\right)$ and $\mathrm{\Upsilon }\left(10753\right)$ resonances, the cross sections for $e^{+}{e}^{-}\to h^{+}{h}^{-}J/\psi (h=\pi /K/p)$ at center-of-mass energies ranging from 3.8 GeV or the production threshold to $5.5/6.0/7.0\mathrm{GeV}$ have been measured via initial-state radiation. The cross sections for the processes $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}J/\psi$ and $e^{+}{e}^{-}\to K^{+}{K}^{-}J/\psi$ are consistent with previously published results. The cross sections for these channels obtained by combining with previous Belle results are also given. The process $e^{+}{e}^{-}\to p\overline{p}J/\psi$ is investigated for the first time. The yields are small and no significant structure is observed in the cross section versus energy. Searches for vector charmoniumlike states in the $h^{+}{h}^{-}J/\psi$ systems, and for associated intermediate states in the $h^{\pm }J/\psi$ systems, are also presented. 

We report the first search for the flavor-changing neutral-current decays $B\to X_s\nu \overline{\nu }$ , where $X_s$ is a hadronic system with strangeness equal to 1, in data collected with the Belle II detector at the SuperKEKB asymmetric-energy $e^{+}{e}^{-}$ collider. The data sample corresponds to an integrated luminosity of $365{\mathrm{fb}}^{-1}$ collected at the $\mathrm{\Upsilon }\left(4S\right)$ resonance and $43{\mathrm{fb}}^{-1}$ collected at a center-of-mass energy 60 MeV below resonance for estimation of $e^{+}{e}^{-}\to q\overline{q}$ continuum background. One of the $B$ mesons from the $\mathrm{\Upsilon }\left(4S\right)\to B\overline{B}$ decay is fully reconstructed in a hadronic decay mode. The $B\to X_s\nu \overline{\nu }$ decay is reconstructed with a sum-of-exclusives approach that uses 30 $X_s$ decay modes. This approach provides high sensitivity to the inclusive decay, despite the presence of two undetected neutrinos. The search is performed in three regions of the $X_s$ mass, $M_{X_s}^{\mathrm{true}}$ , chosen to separate contributions from $K$ , $K^{*}\left(892\right)$ , and heavier strange final states. We do not observe a significant signal and set upper limits at 90% confidence level on the partial branching fractions for the regions $0.0<M_{X_s}^{\mathrm{true}}<0.6\mathrm{GeV}/c^2$ , $0.6<M_{X_s}^{\mathrm{true}}<1.0\mathrm{GeV}/c^2$ , and $1.0\mathrm{GeV}/c^2<M_{X_s}^{\mathrm{true}}$ of $2.2\times {10}^{-5}$ , $9.3\times {10}^{-5}$ , and $30.9\times {10}^{-5}$ , respectively. Combining the three mass regions, we obtain the upper limit on the branching fraction, $B(B\to X_s\nu \overline{\nu })<3.3\times {10}^{-4}$ . 

A<sc>bstract</sc> Using data samples collected by the Belle and Belle II experiments at the Υ(4S) resonance with integrated luminosities of 571 fb⁻¹and 365 fb⁻¹, respectively, we measure the pseudoscalarB-meson mass difference to bem(B⁰) −m(B⁺) = (0.495 ± 0.024 ± 0.005) MeV/c². The results are based on a simultaneous fit to the variable$${\overline{M} }_{bc}$$, which is related to theBmomentum, forB⁰andB⁺candidates; and to the energy dependence of$$\mathcal{R}=\sigma ({e}^{+}{e}^{-}\to {B}^{0}{\overline{B} }^{0}) / \sigma ({e}^{+}{e}^{-}\to {B}^{+}{B}^{-})$$, which is measured using changes in the average center-of-mass energy over the data taking periods. The phase-space hypothesis$$\mathcal{R}={({p}_{{B}^{0}} /{p}_{{B}^{+}})}^{3}$$, upon which previous measurements rely, is strongly disfavored by our fit; the measured mass-difference value for the phase-space hypothesis also differs significantly from our measurement. We constrain$$\mathcal{R}$$in a broader energy range than covered by the direct measurement and extract the energy dependence of$$\mathcal{R}$$in the range from the$$B\overline{B }$$threshold up to 10.59 GeV. We interpret the results using a phenomenological model and constrain the parameters of the$$B\overline{B }$$potential in the isovector channel. 

A<sc>bstract</sc> We study the processesχ_bJωandχ_bJ(π⁺π⁻π⁰)_non−ω(J= 0, 1, 2) at center-of-mass energies$$\sqrt{s}$$from 10.73 to 11.02 GeV using a 142.5 fb⁻¹data sample collected with the Belle detector at the KEKB asymmetric-energye⁺e⁻collider; and at$$\sqrt{s}\sim 10.75$$GeV using a 19.8 fb⁻¹sample collected with Belle II at SuperKEKB. We find that the Υ(10753) state decays intoχ_bJωbut not intoχ_bJ(π⁺π⁻π⁰)_non−ω, while the Υ(10860) state, in contrast, decays intoχ_bJ(π⁺π⁻π⁰)_non−ωbut not intoχ_bJω. The mass and width of the Υ(10753) state are measured to be (10756.1 ± 3.4(stat.) ± 2.7(syst.)) MeV/c²and (32.2 ± 11.3(stat.) ± 14.9(syst.)) MeV. The products of the partial width toe⁺e⁻and branching fractions for Υ(10753)→ χ_b1ωand Υ(10753)→ χ_b2ωare (1.57±0.27(stat.)±0.22(syst.)) eV and (1.39±0.41(stat.)±0.33(syst.)) eV. 

We measure the time- and phase-space-integrated $CP$ asymmetry ${\mathcal{A}}_{CP}$ in $D^0\to {\pi }^{+}{\pi }^{-}{\pi }^0$ decays reconstructed in $e^{+}{e}^{-}\to c\overline{c}$ events collected by the Belle II experiment from 2019 to 2022. This sample corresponds to an integrated luminosity of $428{\mathrm{fb}}^{-1}$ . We require $D^0$ mesons to be produced in $D^{*+}\to D^0{\pi }^{+}$ decays to determine their flavor at production. Control samples of $D^0\to K^{-}{\pi }^{+}$ decays are used to correct for reconstruction-induced asymmetries. The result, ${\mathcal{A}}_{CP}\left(D^0\to {\pi }^{+}{\pi }^{-}{\pi }^0\right)=(0.29\pm 0.27\pm 0.13)\%$ , where the first uncertainty is statistical and the second systematic, is the most precise result to date and is consistent with $CP$ conservation. 

We search for the $e^{+}{e}^{-}\to \gamma {\chi }_{bJ}$ ( $J=0$ , 1, 2) processes at center-of-mass energies $\sqrt{s}=10.653$ , 10.701, 10.746, and 10.804 GeV. These data were collected with the Belle II detector at the SuperKEKB collider and correspond to 3.5, 1.6, 9.8, and $4.7{\mathrm{fb}}^{-1}$ of integrated luminosity, respectively. We set upper limits at the 90% confidence level on the Born cross sections for $e^{+}{e}^{-}\to \gamma {\chi }_{bJ}$ at each center-of-mass energy $\sqrt{s}$ near 10.746 GeV. The upper limits at 90% confidence level on the Born cross sections for $e^{+}{e}^{-}\to \gamma {\chi }_{b1}$ are significantly smaller than the corresponding measured values for $e^{+}{e}^{-}\to \omega {\chi }_{b1}$ and $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}\mathrm{\Upsilon }\left(2S\right)$ at $\sqrt{s}=10.746\mathrm{GeV}$ . 

Using data samples of $988.4{\mathrm{fb}}^{-1}$ and $427.9{\mathrm{fb}}^{-1}$ collected with the Belle and Belle II detectors, we present a study of the singly Cabibbo-suppressed decays ${\mathrm{\Xi }}_c^0\to \mathrm{\Lambda }\eta$ , $\mathrm{\Lambda }{\eta }^{\prime }$ , and $\mathrm{\Lambda }{\pi }^0$ . We observe the decay  ${\mathrm{\Xi }}_c^0\to \mathrm{\Lambda }\eta$ and find evidence for the decay ${\mathrm{\Xi }}_c^0\to \mathrm{\Lambda }{\eta }^{\prime }$ , with corresponding branching ratios determined to be $\mathcal{B}({\mathrm{\Xi }}_c^0\to \mathrm{\Lambda }\eta )/\mathcal{B}({\mathrm{\Xi }}_c^0\to {\mathrm{\Xi }}^{-}{\pi }^{+})=(4.16\pm 0.91\pm 0.23)\%$ and $\mathcal{B}({\mathrm{\Xi }}_c^0\to \mathrm{\Lambda }{\eta }^{\prime })/\mathcal{B}({\mathrm{\Xi }}_c^0\to {\mathrm{\Xi }}^{-}{\pi }^{+})=(2.48\pm 0.82\pm 0.12)\%$ , respectively. We find no significant signal in the ${\mathrm{\Xi }}_c^0\to \mathrm{\Lambda }{\pi }^0$ decay mode and set an upper limit at the 90% credibility level of $\mathcal{B}({\mathrm{\Xi }}_c^0\to \mathrm{\Lambda }{\pi }^0)/\mathcal{B}({\mathrm{\Xi }}_c^0\to {\mathrm{\Xi }}^{-}{\pi }^{+})<3.5\%$ . Multiplying these ratios by the world-average branching fraction of the normalization channel, $\mathcal{B}({\mathrm{\Xi }}_c^0\to {\mathrm{\Xi }}^{-}{\pi }^{+})=(1.43\pm 0.27)\%$ , we obtain the absolute branching fractions of $\mathcal{B}({\mathrm{\Xi }}_c^0\to \mathrm{\Lambda }\eta )=(5.95\pm 1.30\pm 0.32\pm 1.13)\times {10}^{-4}$ , $\mathcal{B}({\mathrm{\Xi }}_c^0\to \mathrm{\Lambda }{\eta }^{\prime })=(3.55\pm 1.17\pm 0.17\pm 0.68)\times {10}^{-4}$ , and an upper limit at the 90% credibility level on the absolute branching fraction of $\mathcal{B}({\mathrm{\Xi }}_c^0\to \mathrm{\Lambda }{\pi }^0)<5.2\times {10}^{-4}$ . The quoted first and second uncertainties are statistical and systematic, respectively, while the third uncertainties arise from the branching fraction of the normalization mode. These results are consistent with most theoretical predictions and further the understanding of the underlying decay mechanisms.