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Roux-en-Y hepaticojejunostomy is a crucial procedure for treating biliary diseases, especially in patients with recurrent hepatolithiasis. However, the safety and efficacy of repeat laparoscopic Roux-en-Y hepaticojejunostomy(R-LRHJS) remain controversial due to the complexity of hepatobiliary stones and the potential for complications. A total of 41 patients admitted to the Department of Hepatobiliary Surgery at the Second Affiliated Hospital of Kunming Medical University from June 2019 to December 2023 were reviewed. 20 patients who underwent repeat R-LRHJS were included in the final analysis. Surgical techniques emphasized meticulous dissection of intra-abdominal adhesions, precise identification of the hepatic hilum bile duct, and careful reconstruction of the biliary-enteric anastomosis. The mean patient age was 54.6 ± 10.7 years. Operative time ranged from 120 to 378 min, with intraoperative blood loss between 10 and 200 ml. Postoperative complications included anastomotic bleeding (2 cases), pancreatic stump bleeding (1 case), duodenal fistula (1 case), and biliary leakage (5 cases). No perioperative deaths occurred. During a 1- to 3-year follow-up, no recurrence of anastomotic stenosis or stone formation was observed on MRCP. The study concludes that R-LRHJS is a feasible and effective treatment for recurrent biliary strictures or stones following initial choledochojejunostomy.

At present, many experimental fast reactors have adopted alloy nuclear fuels, for example, U-Zr alloy fuels. During the neutron irradiation process, vacancies and hydrogen (H) impurity atoms can both exist in U-Zr alloy fuels. Here, first-principles density functional theory (DFT) is employed to study the behaviors of vacancies and H atoms in disordered-γ(U,Zr) as well as their impacts on the electronic structure and mechanical properties. The formation energy of vacancies and hydrogen solution energy are calculated. The effect of vacancies on the migration barrier of hydrogen atoms is revealed. The effect of vacancies and hydrogen atom on densities of states and elastic constants are also presented. The results illustrate that U vacancy is easier to be formed than Zr vacancy. The H interstitial prefers the tetrahedral site. Besides, U vacancy shows H-trap ability and can raise the H migration barrier. Almost all the defects lead to decreases in electrical conductivity and bulk modulus. It is also found that the main effect of defects is on the U-5f orbitals. This work provides a theoretical understanding of the effect of defects on the electronic and mechanical properties of U-Zr alloys, which is an essential step toward tailoring their performance.

Brewing water plays a crucial role in flavor and potential healthy functions of tea infusion. In this study, seven water samples with different physicochemical properties were selected to brew green tea. Results showed that the brewing water with higher minerals level and pH value would reduce the yield of catechins in tea infusion, which in turn caused the decrease of antioxidant activity to a large extent. Besides, it was found that EGCG, as a major contributor to the antioxidant activity of green tea infusion, was influenced differently by different metal ions, among which Ca2+/Mg2+ could enhance the antioxidant activity of EGCG solutions with different concentration through synergistic effect, particularly Ca2+, and the effect was more markable at a higher EGCG concentration. These results offered theoretical direction to the selection of tea brewing water for consumers and gave a new sight to the effects of metal ions on the antioxidant capacity of EGCG.

Most of the congenital heart diseases can be diagnosed in utero using fetal echocardiography. With the development of ultrasonography and intrauterine cardiac intervention technique, fetal cardiac intervention （FC1） for critical aortic stenosis, highly restrictive or intact atrial septum, pulmonary atresia with an intact ventricular septum （PA/ IVS）, and critical pulmonary stenosis （CPS） are available in more countries.

Hexamethylenediamine（HMDA） is an important reagent for the synthesis of Nylon-6,6, and it is usually produced by the hydrogenation of adiponitrile using a toxic reagent of hydrocyanic acid. Herein, we developed an environmental friendly route to produce HMDA via catalytic reductive amination of 1,6-hexanediol（HDO） in the presence of hydrogen. The activities of several heterogeneous metal catalysts such as supported Ni, Co, Ru, Pt, Pd catalysts were screened for the present reaction in supercritical ammonia without any additives. Among the catalysts examined, Ru/Al2O3 presented a high catalytic activity and highest selectivity for the desired product of HMDA. The high performance of Ru/Al2O3 was discussed based on the Ru dispersion and the surface properties like the acid-basicity. In addition, the reaction parameters such as reaction temperature,time, H2 and NH3 pressure were examined, and the reaction processes were discussed in detail.

This feature article focuses on the recent development of giant molecules,which has emerged at the interface among chemistry,physics,and bio-science.Their molecular designs are inspired by natural polymers like proteins and are modularly constructed from molecular nanoparticle building blocks via sequential ＂click＂ chemistry.Most important molecular parameters such as topology,composition,and molecular weight can be precisely controlled.Their hierarchical assembly reveals many features reminiscent of both small molecules and proteins yet unusual for conventional synthetic polymers.These features are summarized and compared along with synthetic polymers and proteins.Specifically,examples are given in each category of giant molecules to illustrate the characteristics of their hierarchical assembly across different length,time and energy scales.The idea of ＂artificial domain＂ is presented in analogy to the structural domains in proteins.By doing so,we aim to develop a rational and modular approach toward functional materials.The factors that dominate the materials functions are discussed with respect to the precision and dynamics of the assembly.The complexity of structure-function relationship is acknowledged,which suggests that there is still a long way to go toward the convergence of synthetic polymers and biopolymers.

The morphology of the gully longitudinal profile （GLP） is an important topographic index of the gully bottom associated with the evolution of the gullies. This index can be used to predict the development trend and evaluate the eroded volumes and soil losses by gullying. To depict the morphology of GLP and understand its controlling factors, the Global Positioning System Real-time Kinematic （GPS RTK） and the total station were used to measure the detail points along the gully bottom of 122 gullies at six sites of the Yuanmou dry-hot Valley. Then, nine parameters including length （Lt）, horizontal distance （Dh）, height （H）, vertical erosional area （A）, vertical curvature （Co）, concavity （Ca）, average gradient （Ga）, gully length-gradient index （GL）, normalized gully length-gradient index （Ngl）, were calculated and mapped using CASS, Excel and SPSS. The results showed that this study area is dominated by slightly concave and medium gradient GLPs, and the lithology of most gullies is sandstone and siltstone. Although different types of GLPs appear at different sites, all parameters present a positively skewed distribution. There are relatively strong correlations between several parameters： namely Lt and H, Dh and H, Lt and A, Dh and A, H and GL. Most GLPs, except three, have a best fit of exponential functions with quasi- straight shapes. Soil properties, vegetation coverage, piping erosion and topography are important factors to affect the GLP morphology. This study provides useful insight into the knowledge of GLP morphology and its influential factors that are of critical importance to prevent and control gully erosion.

We present two robust quantum secure direct communication （QSDC） schemes with a quantum one-time pad over a collective-noise channel. Each logical qubit is made up of two physical qubits and it is invariant over a collective-noise channel. The two photons in each logical qubit can be produced with a practically entangled source, i.e., a parametric down-conversion source with a beta barium borate crystal and a pump pulse of ultraviolet light. The information is encoded on each logical qubit with two logical unitary operations, which will not destroy the antinoise feather of the quantum systems. The receiver Bob can read out the sender＇s message directly with two single-photon measurements on each logical qubit, instead of Bell-state measurements, which will make these protocols more convenient in a practical application. With current technology, our two robust QSDC schemes are feasible and may be optimal ones.

The SWI/SNF chromatin-remodeling complexes utilize energy from ATP hydrolysis to reposition nucleosomes and regulate the expression of human genes. Here, we studied the roles of human Brahma （hBrm） and Brahma-related gene 1 （Brgl）, the ATPase subunits of the SWI/SNF complexes, in regulating human genes. Our results indicate that both hBrm and Brgl interact with Signal transducer and activator of transcription （Stat） 1 in vitro. However, Statl in its native form only recruits hBrm to IFNy-activated sequences （GAS） of individual genes; by contrast, in a stress- induced phosphorylated form, Statl mainly binds to Brgl. Under basal conditions, hBrm is recruited by native Statl to the GAS and exists in a mSin3/HDAC co-repressor complex on the hsp90a gene, which shows a compact chromatin structure. Upon heat-shock, hBrm is acetylated by p300 and dissociates from the co-repressor complex, which the phosphorylated St~tl is increased, and binds and recruits Brgl to the GAS, leading to elevated induction of the gene. This hBrm/Brgl switch also occurs at the GAS of all of the three examined immune genes in heat-shocked cells; how- ever, this switch only occurs in specific cell types upon exposure to IFNy. Regardless of the stimulus, the hBrm/Brgl switch at the GAS elicits an increase in gene activity. Our data are consistent with the hypothesis that the hBrm/Brgl switch is an indicator of the responsiveness of a gene to heat-shock or IFNy stimulation and may represent an ＂on-off switch＂ of gene expression in vivo.

The knowledge of the hyperpolarizabilities of atoms and ions is helpful for the analysis of the high order effects of the frequency shifts in precision spectroscopy experiments. Liu et al. [Phys. Rev. Lett. 114, 223001 （2015）] proposed to establish all-optical trapped ion clocks using laser at the magic wavelength for clock transition. To evaluate the high-order frequency shifts in this new scheme of optical clocks, hyperpolarizabilities are needed, but absent. Using the finite field method based on the B-spline basis set and model potentials, we calculated the electric-field-dependent energy shifts of the ground and low-lying excited states in Be＋, Mg＋, and Ca＋ in the field strength range of 0.0-6×10-5 a.u.. The scalar and tensor polarizabilities （α0, α2） and hyperpolarizabilities （Y0,Y2, 74） were deduced. The results of the hyperpolarizabilities for Be＋ showed good agreement with the values in literature, implying that the present method can be applied for the effective estimation of the atomic hyperpolarizabilities, which are rarely reported but needed in experiments. The feasibility of optical trapping of Ca＋ is discussed, and the contributions of hyperpolarizabilities to the transition frequency shift for Ca＋ in the optical dipole trap are estimated using quasi-electrostatic approximation.