Three-dimensional flat Landau levels in an inhomogeneous acoustic crystal.

When electrons moving in two dimensions (2D) are subjected to a strong uniform magnetic field, they form flat bands called Landau levels (LLs). LLs can also arise from pseudomagnetic fields (PMFs) induced by lattice distortions. In three-dimensional (3D) systems, there has been no experimental demonstration of LLs  as a type of flat band thus far. Here, we report the experimental realization of a flat 3D LL in an acoustic crystal. Starting from a lattice whose bandstructure exhibits a nodal ring, we design an inhomogeneous distortion corresponding to a specific pseudomagnetic vector potential (PVP). This distortion causes the nodal ring states to break up into LLs, including a zeroth LL that is flat along all three directions. These findings suggest the possibility of using nodal ring materials to generate 3D flat bands, allowing access to strong interactions and other attractive physical regimes in 3D.

Vacuum bell therapy for pectus excavatum: a retrospective study.

BACKGROUND: Pectus excavatum, the most common chest wall deformity, is frequently treated with Nuss procedure. Here we will describe non-invasive procedure and analyze the variables associated vacuum bell therapy for patients with pectus excavatum. METHODS: Retrospective case-control study in a single center between July 2018 and February 2022, including patients with pectus excavatum treated with vacuum bell. Follow-up was continued to September 2022. The Haller index and Correction index was calculated before and after treatment to analysis the effectiveness of vacuum bell therapy. RESULTS: There were 98 patients enrolled in the treatment group, with 72 available for analysis, and the follow-up period ranged from 1.1 to 4.4 years (mean 3.3 years). When analyzing with the Haller Index, 18 patients (25.0%) showed excellent correction, 13 patients (18.1%) achieved good correction, and 4 patients (5.6%) had fair correction. The remaining patients had a poor outcome. Characteristics predicting a non-poor prognosis included initial age ≤ 11 years (OR = 3.94, p = 0.013) and patients with use over 24 consecutive months (OR = 3.95, p = 0.013). A total of 9 patients (12.5%) achieved a CI reduction below 10. Patients who started vacuum bell therapy at age > 11 had significantly less change compared to those who started at age ≤ 11 (P < 0.05). Complications included chest pain (5.6%), swollen skin (6.9%), chest tightness (1.4%) and erythema (15.3%). CONCLUSIONS: A certain percentage of patients with pectus excavatum can achieve excellent correction when treated with pectus excavatum therapy. Variables predicting better outcome including initial age ≤ 11 years both in HI and CI and vacuum bell use over 24 consecutive months in HI. In summary, pectus excavatum is an emerging non-invasive therapy for pectus excavatum and will be widely performed in a certain group of patients.

Stiefel-Whitney topological charges in a three-dimensional acoustic nodal-line crystal.

Band topology of materials describes the extent Bloch wavefunctions are twisted in momentum space. Such descriptions rely on a set of topological invariants, generally referred to as topological charges, which form a characteristic class in the mathematical structure of fiber bundles associated with the Bloch wavefunctions. For example, the celebrated Chern number and its variants belong to the Chern class, characterizing topological charges for complex Bloch wavefunctions. Nevertheless, under the space-time inversion symmetry, Bloch wavefunctions can be purely real in the entire momentum space; consequently, their topological classification does not fall into the Chern class, but requires another characteristic class known as the Stiefel-Whitney class. Here, in a three-dimensional acoustic crystal, we demonstrate a topological nodal-line semimetal that is characterized by a doublet of topological charges, the first and second Stiefel-Whitney numbers, simultaneously. Such a doubly charged nodal line gives rise to a doubled bulk-boundary correspondence-while the first Stiefel-Whitney number induces ordinary drumhead states of the nodal line, the second Stiefel-Whitney number supports hinge Fermi arc states at odd inversion-related pairs of hinges. These results experimentally validate the two Stiefel-Whitney topological charges and demonstrate their unique bulk-boundary correspondence in a physical system.

Sea Buckthorn Pretreatment, Drying, and Processing of High-Quality Products: Current Status and Trends.

Sea buckthorn is a kind of berry rich in nutritional and industrial value. Due to its thin skin, juicy pulp, and short shelf life, it is usually preserved via freezing methods or directly processed into sea buckthorn puree after harvest. It can also be dried and processed into products such as dried sea buckthorn fruit, freeze-dried sea buckthorn powder, and sea buckthorn oil. This review, therefore, provides an overview of the existing state of drying and high-quality processing of sea buckthorn. The effects of different pretreatment and drying techniques on the drying characteristics and quality of sea buckthorn and the existing problems of superior-quality processing of sea buckthorn products are summarised. The development trend of sea buckthorn drying methods and the ways to achieve high-quality processing of sea buckthorn products are indicated. These ways are mainly related to the following: (1) The application of combined pretreatment and drying techniques to find a balance between economy, ecology, and efficiency; (2) Introducing new online measurement and control technology into drying equipment; (3) Optimising the existing process to form a complete sea buckthorn industrial chain and develop the sea buckthorn deep-processing industry.

Erratum: Observation of π/2 Modes in an Acoustic Floquet System [Phys. Rev. Lett. 129, 254301 (2022)].

This corrects the article DOI: 10.1103/PhysRevLett.129.254301.

Observation of Topological Edge States in Thermal Diffusion.

Topological band theory predicts that bulk materials with nontrivial topological phases support topological edge states. This phenomenon is universal for various wave systems and is widely observed for electromagnetic and acoustic waves. Here, the notion of band topology is extended from wave to diffusion dynamics. Unlike wave systems that are usually Hermitian, diffusion systems are anti-Hermitian with purely imaginary eigenvalues corresponding to decay rates. By direct probe of the temperature diffusion, the Hamiltonian of a thermal lattice is experimentally retrieved, and the emergence of topological edge decays is observed within the gap of bulk decays. The results of this work show that such edge states exhibit robust decay rates, which are topologically protected against disorder. This work constitutes a thermal analogue of topological insulators and paves the way to exploring defect-immune heat dissipation.

Projectively Enriched Symmetry and Topology in Acoustic Crystals.

Symmetry plays a key role in modern physics, as manifested in the revolutionary topological classification of matter in the past decade. So far, we seem to have a complete theory of topological phases from internal symmetries as well as crystallographic symmetry groups. However, an intrinsic element, i.e., the gauge symmetry in physical systems, has been overlooked in the current framework. Here, we show that the algebraic structure of crystal symmetries can be projectively enriched due to the gauge symmetry, which subsequently gives rise to new topological physics never witnessed under ordinary symmetries. We demonstrate the idea by theoretical analysis, numerical simulation, and experimental realization of a topological acoustic lattice with projective translation symmetries under a Z_{2} gauge field, which exhibits unique features of rich topologies, including a single Dirac point, Möbius topological insulator, and graphenelike semimetal phases on a rectangular lattice. Our work reveals the impact when gauge and crystal symmetries meet together with topology and opens the door to a vast unexplored land of topological states by projective symmetries.

Observation of π/2 Modes in an Acoustic Floquet System.

Topological phases of matter have remained an active area of research in the last few decades. Periodic driving is a powerful tool for enriching such exotic phases, leading to various phenomena with no static analogs. One such phenomenon is the emergence of the elusive π/2 modes, i.e., a type of topological boundary state pinned at a quarter of the driving frequency. The latter may lead to the formation of Floquet parafermions in the presence of interaction, which is known to support more computational power than Majorana particles. In this Letter, we experimentally verify the signature of π/2 modes in an acoustic waveguide array, which is designed to simulate a square-root periodically driven Su-Schrieffer-Heeger model. This is accomplished by confirming the 4T-periodicity (T being the driving period) profile of an initial-boundary excitation, which we also show theoretically to be the smoking gun evidence of π/2 modes. Our findings are expected to motivate further studies of π/2 modes in quantum systems for potential technological applications.

The relationships between bariatric surgery and sexual function: current evidence based medicine.

BACKGROUND: Controversy remains despite several studies have discussed the role of bariatric surgery in improving male's sexual function. This study aims to evaluate the efficacy of bariatric surgery in promoting male's erectile function. METHODS: PubMed, EMbase, The Cochrane Library, CNKI and Clinical Trails.gov were searched from database inception to May 2019. The language of publication was limited in English. The International Index of Erectile Function (IIEF) score and Brief Male Sexual Function Inventory (BSFI) score were set as the primary outcome. RESULTS: Eleven studies with a total of 370 patients were enrolled in this meta-analysis. The results showed significant improvement in the IIEF score (erectile function: MD = 5.33, 95% CI 4.12-6.54; intercourse satisfaction: MD = 2.57, 95% CI 1.19-3.94; orgasmic function: MD = 0.50, 95%CI 0.60-0.94; overall satisfaction: MD = 1.67, 95% CI 0.78-2.56; sexual desire: MD = 1.27, 95% CI 0.61-1.93; total erectile function: MD = 7.21, 95% CI 4.33-10.10) and the BSFI score (erection: MD =2.53, 95% CI 2.39-2.67; ejaculation: MD = 1.40, 95% CI 1.28-1.51; desire: MD =1.40, 95% CI 1.32-1.49; problem assessment: MD = 2.20, 95% CI 2.06-2.34; sexual satisfaction: MD = 0.70, 95% CI 0.60-0.76) in obese individuals after bariatric surgery. CONCLUSIONS: This systematic review and meta-analysis indicated that bariatric surgery could be effective in promoting males's sexual function for obese individuals.

A randomized trial comparing radiofrequency ablation and surgical resection for HCC conforming to the Milan criteria.

OBJECTIVE: To compare the long-term outcomes of surgical resection and radiofrequency ablation for the treatment of small hepatocellular carcinoma (HCC). SUMMARY BACKGROUND DATA: Radiofrequency ablation (RFA) is a promising, emerging therapy for small HCC. Whether it is as effective as surgical resection (RES) for long-term outcomes is still indefinite. METHODS: Two hundred thirty HCC patients who met the Milan criteria and were suitable to be treated by either RES or RFA entered into a randomized controlled trial. The patients were regularly followed up after treatment for 5 years (except for those who died). The primary end point was overall survival; the secondary end points were recurrence-free survival, overall recurrence, and early-stage recurrence. RESULTS: The 1-, 2-, 3-, 4- and 5-year overall survival rates for the RFA group and the RES group were 86.96%, 76.52%, 69.57%, 66.09%, 54.78% and 98.26%, 96.52%, 92.17%, 82.60%, 75.65%, respectively. The corresponding recurrence-free survival rates for the 2 groups were 81.74%, 59.13%, 46.08%, 33.91%, 28.69% and 85.22%, 73.92%, 60.87%, 54.78%, 51.30%, respectively. Overall survival and recurrence-free survival were significantly lower in the RFA group than in the RES group (P = 0.001 and P = 0.017). The 1-, 2-, 3-, 4-, and 5-year overall recurrence rates were 16.52%, 38.26%, 49.57%, 59.13%, and 63.48% for the RFA group and 12.17%, 22.60%, 33.91%, 39.13%, and 41.74% for the RES group. The overall recurrence was higher in the RFA group than in the RES group (P = 0.024). CONCLUSIONS: Surgical resection may provide better survival and lower recurrence rates than RFA for patients with HCC to the Milan criteria.

[Augmented hepatic regeneration of living donor liver graft by intraportal insulin administration].

OBJECTIVE: To evaluate the effect of postoperative intraportally administration of insulin on hepatic regeneration in adult patients underwent living donor right lobe liver transplantation (LDLT). METHODS: From July 2005 to September 2007, 15 right lobe LDLT adult recipients voluntarily receiving posttransplant intraportal insulin administration, without postoperative vascular and bile duct complications, without immune rejection, with more than 1 month survival and complete clinical data were enrolled in this study as intraportal insulin-therapy group (Group I). Another consecutive 15 right lobe LDLT adult recipients meeting the upwards referred criteria were enrolled in as non-insulin-therapy control group (Group NI). Recipients in Group I were treated postoperatively with intraportal insulin infusion, as follows: a 18-gauge catheter was inserted into right gastro-omental vein during surgery, regular insulin was administered just after the operation at the rate of 2 units/hour for 7 days. Liver function and serum insulin level were measured at before-operative day 1, postoperative day (POD) 7 and 30. Graft volume (GV) were measured during operation, and at POD 7 and 30. RESULTS: The rate defined as ratio of POD 7 GV/operation GV in Group I was higher than that of Group NI [(186.1 +/- 35.4)% vs. (160.6 +/- 22.1)%, P < 0.05]. The rate defined as ratio of POD 7 GRWR/operation GRWR was also higher in Group I than Group NI [(179.0 +/- 35.8) % vs. (156.6 +/- 18.5%, P < 0.05], whereas significant differences were not appeared between two groups in terms of regeneration rates at POD 30. Serum levels of total bilirubin, aspartate aminotransferase and alanine aminotransferase in Group I were lower than that in Group NI at POD 7 (P < 0.05). Significant differences were not presented between two groups in terms of post-transplant serum insulin levels and total insulin dosage by subcutaneous administration and venous injection (P > 0.05). CONCLUSIONS: These results suggest that intraportal insulin administration could augment liver graft regeneration during the first postoperative week.

[Excision and reconstruction of anomalous portal venous branching in adult-to-adult right lobe living donor liver transplantation].

OBJECTIVE: To discuss the techniques for excision and reconstruction of anomalous portal venous branches (APVB) in adult-to-adult right lobe living donor liver transplantation (A-A RL LDLT). METHODS: From February 2002 to April 2007, 70 cases of A-A RL LDLT were performed. Preoperative three-dimensional computed tomography of the donor revealed the configurations of hepatic artery, portal vein and hepatic vein. Nine donors had anomalous portal venous branching (APVB). The APVB were type II (trifurcation) in 7 cases and type III in two. Except the excision of APVB with a common opening by a narrow bridge of main portal vein tissue in one type II donor, all the right APVB were transected on the principal of donor priority: right APVB being excised approximately 2-3 mm from the confluence while leaving the donor's portal vein intact. In type II APVB, the donor portal venous branches were transected with separate two openings and reconstructed as double anastomoses in 4 cases, with separate two openings joined as a common orifice at the back table and reconstructed as single anastomoses in 2 cases, and with one common opening with narrow-bridge of tissue and reconstructed as single anastomoses in 1 case. In type III APVB, the APVB were transected with separate two openings and were reconstructed by double anastomoses in 1 case and by a new technique named U-shaped vein graft interposition in the another one. RESULTS: There were no vascular complications such as portal vein stricture or thrombosis, hepatic artery stricture or thrombosis and hepatic vein outflow stricture in all 9 recipients transplanted with grafts with APVB. Only the type II APVB donor undergoing a excision of APVB with a common opening by a narrow bridge of main portal vein tissue developed portal vein thrombosis on the third postoperative day and underwent thrombectomy followed by repair with vein patch plasty. The velocity of blood flow in the U-graft was normal. CONCLUSIONS: It is feasible and safe of APVB excision on the principal of donor priority and reconstruction including double anastomoses and the novel U-graft interposition in A-A RL LDLT, and has a good outcome without increasing the management difficulty.