THE DRAWBACKS AND REFORM OF CHINA’S CURRENT RURAL LAND SYSTEM: AN ANALYSIS BASED ON CONTRACT, PROPERTY RIGHTS AND RESOURCE ALLOCATION

This article analyzes the drawbacks of China’s current rural land system (the Household Contract System based on the collective ownership) mainly from the perspectives of contract, property rights and resource allocation. This article defines the Household Contract System as a lease where the collective (landowner) leases land to its members to farm independently. The drawbacks of China\u27s current rural land system mainly include instability of the peasants’ land use right and insecurity of their land income right weakening peasants’ enthusiasm for investment in land, and a lot of restrictions on the transfer of peasants’ land leases obstructing the flows and optimized allocation of labor, land and capital. According to analysis, the drawbacks of China’s current rural land system result mainly from the collective ownership and the government-run nature of the collective. This article then makes and elaborates the proposition of the privatization of rural land to peasants. It also analyzes the government’s land rights in private ownership of land and refutes the popular arguments against the privatization of rural land

ANALYSIS ON CONSTRUCTION DEFORMATION AND SUPPORTING STRUCTURE OF TWO-STEP AND THREESECTION EXCAVATION METHOD FOR SUPER LARGER SPAN HIGHWAY TUNNEL

The super larger span tunnel is a common form of highway reconstruction and expansionprojects in recent years. In order to determine the stability of tunnel structure of the two-step andthree-section excavation method of the III-level surrounding rock mass of the super larger spanhighway, the field test method was adopted. Relying on the Laohushan Tunnel in Jinan, Shandong,China, the deformation and the structure performance of the super larger span tunnel in III-levelsurrounding rock mass are analyzed, and the safety of the tunnel and the support structure isevaluated on this basis. The results show that the maximum settlement of the arch section of theGrade III surrounding rock section is 12.5mm, and the maximum clearance convergence is 5.8mm.Both of them are much smaller than the design reserved deformation of 80mm. The maximumpressure of the surrounding rock is 0.091MPa, showing that the force acting on the supportingstructure by surrounding rock mass is small. The inner and outer arched parts of the steel frameare subject to large stresses, and most of them are tensile stresses. The maximum stress of thesteel frame is 283 MPa, and occurs at the inner side of right arch waist. Although the local stressexceeds the yield strength of the steel (235 MPa), it does not exceed its ultimate compressivestrength of 400 MPa, and the tensile and compressive stress values of the other inner and outerparts do not exceed the yield strength. Mainly, the maximum stress appears on the left side wall,reaching 4.83 MPa, which is far less than the ultimate compressive strength of sprayed concrete(11.9 MPa). For super larger span highway tunnels, located in III-level surrounding rock mass,constructed by two-step and three-section excavation method, the initial support effectivelycontrolled the tunnel deformation, the supporting structures were fully protected and the tunnelstructure was stable. The super larger span tunnel is a common form in the road reconstructionand expansion project in recent years. In order to determine the stability of tunnel structure of thetwo steps and three excavation method of the III-level surrounding rock mass of the super largerspan highway, the field test method was adopted. Relying on the Laohushan Tunnel, thedeformation and the structure performance of the super larger span tunnel in III-level surroundingrock mass were analyzed. The results show that the maximum settlement of arch of the III-levelsurrounding rock mass is 12.5mm in super larger span highway tunnel, and the maximumclearance convergence is 5.8mm. Both of them are smaller than the design reserved deformationof 80mm. The maximum surrounding rock mass pressure is 0.091MPa, the force acting on thesupporting structure by surrounding rock mass are small. The inner and outer arched parts of the steel frame bear larger stress, and are mostly tensile stress. The maximum stress on inner side ofthe steel frame is 283 MPa, and occurs at the right arch waist. The maximum stress on the outerside of the steel frame is184 MPa, and occurs at the vault. The steel frame plays an important rolein the initial support, however the force does not reach the yield strength of the steel. The shotcreteis subjected to pressure, the maximum stress appears on the left side wall is 4.83 MPa, which ismuch smaller than the ultimate compressive strength of shotcrete of 25 MPa. So for super largerspan highway tunnels, located in III-level surrounding rock mass, constructed by two-step andthree-excavation method, the whole structure is stable

Allograft function predicts mortality in kidney transplant recipients with severe COVID-19: a paradoxical risk factor

IntroductionKidney transplant recipients (KTRs) are at a higher risk of severe coronavirus disease (COVID-19) because of their immunocompromised status. However, the effect of allograft function on the prognosis of severe COVID-19 in KTRs is unclear. In this study, we aimed to analyze the correlation between pre-infection allograft function and the prognosis of severe COVID-19 in KTRs.MethodsThis retrospective cohort study included 82 patients who underwent kidney transplantation at the Sichuan Provincial Peoples Hospital between October 1, 2014 and December 1, 2022 and were diagnosed with severe COVID-19. The patients were divided into decreased eGFR and normal eGFR groups based on the allograft function before COVID-19 diagnosis (n=32 [decreased eGFR group], mean age: 43.00 years; n=50 [normal eGFR group, mean age: 41.88 years). We performed logistic regression analysis to identify risk factors for death in patients with severe COVID-19. The nomogram was used to visualize the logistic regression model results.ResultsThe mortality rate of KTRs with pre-infection allograft function insufficiency in the decreased eGFR group was significantly higher than that of KTRs in the normal eGFR group (31.25% [10/32] vs. 8.00% [4/50], P=0.006). Pre-infection allograft function insufficiency (OR=6.96, 95% CI: 1.4633.18, P=0.015) and maintenance of a mycophenolic acid dose >1500 mg/day before infection (OR=7.59, 95% CI: 1.0853.20, P=0.041) were independent risk factors, and the use of nirmatrelvir/ritonavir before severe COVID-19 (OR=0.15, 95% CI: 0.030.72, P=0.018) was a protective factor against death in severe COVID-19.ConclusionsPre-infection allograft function is a good predictor of death in patients with severe COVID-19. Allograft function was improved after treatment for severe COVID-19, which was not observed in patients with non-severe COVID-19

Topological Microlaser with A non-Hermitian Topological Bulk

Bulk-edge correspondence, with quantized bulk topology leading to protected edge states, is a hallmark of topological states of matter and has been experimentally observed in electronic, atomic, photonic, and many other systems. While bulk-edge correspondence has been extensively studied in Hermitian systems, a non-Hermitian bulk could drastically modify the Hermitian topological band theory due to the interplay between non-Hermiticity and topology; and its effect on bulk-edge correspondence is still an ongoing pursuit. Importantly, including non-Hermicity can significantly expand the horizon of topological states of matter and lead to a plethora of unique properties and device applications, an example of which is a topological laser. However, the bulk topology, and thereby the bulk-edge correspondence, in existing topological edge-mode lasers is not well defined. Here, we propose and experimentally probe topological edge-mode lasing with a well-defined non-Hermitian bulk topology in a one-dimensional (1D) array of coupled ring resonators. By modeling the Hamiltonian with an additional degree of freedom (referred to as synthetic dimension), our 1D structure is equivalent to a 2D non-Hermitian Chern insulator with precise mapping. Our work may open a new pathway for probing non-Hermitian topological effects and exploring non-Hermitian topological device applications.Comment: 8 pages, 4 figure

Spectral fluctuations in the interacting boson model

The energy dependence of the spectral fluctuations in the interacting boson model (IBM) and its connections to the mean-field structures have been analyzed through adopting two statistical measures, the nearest neighbor level spacing distribution $P(S)$ measuring the chaoticity (regularity) in energy spectra and the $\Delta_3(L)$ statistics of Dyson and Metha measuring the spectral rigidity. Specifically, the statistical results as functions of the energy cutoff have been worked out for different dynamical situations including the U(5)-SU(3) and SU(3)-O(6) transitions as well as those near the AW arc of regularity. It is found that most of the changes in spectral fluctuations are triggered near the stationary points of the classical potential especially for the cases in the deformed region of the IBM phase diagram. The results thus justify the stationary point effects from the point of view of statistics. In addition, the approximate degeneracies in the $2^+$ spectrum on the AW arc is also revealed from the statistical calculations

A cuproptosis-associated long non-coding RNA signature for the prognosis and immunotherapy of lung squamous cell carcinoma

Cuproptosis, a copper-induced mechanism of mitochondrial-related cell death, has been implicated as a breakthrough in the treatment of cancer and has become a new treatment strategy. Furthermore, long non-coding RNA (lncRNA) can change the biological activities of tumor cells. Worldwide, lung squamous cell carcinoma (LUSC) is among the most common annoying tumors. LncRNAs related to cuproptosis are not researched at LUSC. Our research intends to develop a signature on the basis of cuproptosis-associated lncRNAs, which can predict LUSC prognosis and investigate LUSC immunological features. The TCGA database was used to retrieve LUSC transcriptome, clinical, and gene mutation data. For statistical analysis, we utilized the R program. We created a signature consisting of three cuproptosis-related lncRNAs in this investigation (including AC002467.1, LINC01740, and LINC02345). Survival analyses and Receiver Operating Characteristic curves demonstrated that this signature possessed powerful predictive capability. The signature’s ability to predict was confirmed by a Receiver Operating Characteristic curve and principal component analysis. Notably, the patient with a high-risk score and a high tumor mutation burden level had a lower survival time. Furthermore, the tumor immune dysfunction and exclusion analysis showed that these individuals with low-risk scores may benefit from immunotherapy. The signature constructed by three cuproptosis-associated lncRNAs may be prognostic markers of LUSC. It contributes to immunotherapy and offers LUSC’s therapy a new treatment direction

The G Protein Coupled Receptor 3 Is Involved in cAMP and cGMP Signaling and Maintenance of Meiotic Arrest in Porcine Oocytes

The arrest of meiotic prophase in mammalian oocytes within fully grown follicles is dependent on cyclic adenosine monophosphate (cAMP) regulation. A large part of cAMP is produced by the Gs-linked G-protein-coupled receptor (GPR) pathway. In the present study, we examined whether GPR3 is involved in the maintenance of meiotic arrest in porcine oocytes. Expression and distribution of GPR3 were examined by western blot and immunofluorescence microscopy, respectively. The results showed that GPR3 was expressed at various stages during porcine oocyte maturation. At the germinal vesicle (GV) stage, GPR3 displayed a maximal expression level, and its expression remained stable from pro-metaphase I (MI) to metaphase II (MII). Immunofluorescence staining showed that GPR3 was mainly distributed at the nuclear envelope during the GV stage and localized to the plasma membrane at pro-MI, MI and MII stages. RNA interference (RNAi) was used to knock down the GPR3 expression within oocytes. Injection of small interfering double-stranded RNA (siRNA) targeting GPR3 stimulated meiotic resumption of oocytes. On the other hand, overexpression of GPR3 inhibited meiotic maturation of porcine oocytes, which was caused by increase of cGMP and cAMP levels and inhibition of cyclin B accumulation. Furthermore, incubation of porcine oocytes with the GPR3 ligand sphingosylphosphorylcholine (SPC) inhibited oocyte maturation. We propose that GPR3 is required for maintenance of meiotic arrest in porcine oocytes through pathways involved in the regulation of cAMP and cGMP