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Solar wind observations in the space of the proton temperature anisotropy Tp⊥/Tp‖ ${T}_{p\perp }/{T}_{p\Vert }$ versus parallel proton beta βp‖ ${\beta }_{p\Vert }$ always show a distorted rhomboid‐like pattern, where the boundaries of this plot are associated with several instabilities. However, the specific mechanism on the constraint of the proton temperature anisotropy is unclear in the low‐beta βp‖<1 ${\beta }_{p\Vert }< 1$ plasma. In this work, we study the kinetic instabilities driven by proton temperature anisotropy and alpha beam with the Vlasov theory and investigate the nonlinear evolution of these instabilities with hybrid simulations. We also compare the theoretical and simulation results with Wind observations. The alpha beam with drift velocity vα/vA>1 ${v}_{\alpha }/{v}_{A} > 1$ leads to a new kind of Alfvén/ion‐cyclotron instability (α $\alpha $A/IC instability) in the region of βp‖≤0.2 ${\beta }_{p\Vert }\le 0.2$. In the region of βp‖≤0.2 ${\beta }_{p\Vert }\le 0.2$ and Tp⊥1 ${v}_{\alpha }/{v}_{A} > 1$ can drive a new kind of alpha‐Alfvén/ion cyclotron (α $\alpha $A/IC) instabilityIn the low‐beta regime, the α $\alpha $A/IC instability leads to anti‐correlation between proton temperature anisotropy and parallel proton betaThe α $\alpha $A/IC instability provides a restriction imposed on the distribution of proton temperature anisotropy in the low‐beta plasma [ABSTRACT FROM AUTHOR]

In deep excavations, pre-excavation dewatering (PED) usually causes notable diaphragm wall (D-wall) deformation and ground settlement. However, this problem has not attracted sufficient attention. In this paper, the mechanisms and control methods of settlement caused by PED in a deep excavation in Tianjin, China are analysed. A hydraulic connection between the soil inside and outside the excavation area due to aquifer leakage was observed during PED. Therefore, although the first level of struts had been installed before PED, the deformation of the D-wall and ground settlement reached 6·9 mm and 12·5 mm, approximately 29·0% and 73·5% of the maximum allowable values, respectively. The monitoring results demonstrated that leaky aquifers could reduce the deformation of the D-wall but increased the magnitude and extent of ground settlement. Based on the numerical simulations of D-wall deformation and groundwater change, in this case, the ground settlement within the area extending two times the depth of unloading (two times the depth of dewatering, 2Hd) from the excavation was found to be caused by both the deformation of the D-wall and the drawdown of the groundwater, whereas the noticeable settlement in the area beyond 2Hd was caused by only the drawdown of the groundwater. When hydraulic connections exist between the soil inside and outside the excavation area, artificial recharge should be used to control the noticeable settlement induced by groundwater drawdown. [ABSTRACT FROM AUTHOR]

PbZr0.2Ti0.8O3/La2Zr2O7 (PZT/LZO) bilayer and amorphous La2Zr2O7 thin films were fabricated using pulse laser deposition and radio frequency magnetron sputtering. A typical and robust bipolar resistive switching (RS) behavior was revealed in the PZT/LZO heterostructure at room temperature. Compared with LZO single film, the PZT/LZO heterostructure exhibits a better RS property with a one order magnitude higher HRS/LRS ratio. More interestingly, the RS of PZT/LZO structure exhibited a stable degradation RS performance until 103 cycles at room temperature. The conduction mechanism in PZT/LZO bilayer can be attributed to the space-limited-conduction (SCLC) and Schottky-barrier models, while LZO thin film was attributed to SCLC conduction. As a result, the PZT/LZO bilayer under polarization field tuning shows an effective way to improve the RS performance and provides a new route for RRAM applications. [ABSTRACT FROM AUTHOR]

BACKGROUND: The prognosis of natural killer/T cell lymphoma (NKTCL) with multifocal small intestine involvement complicated by intestinal perforation is extremely poor. There is no evidence-based treatment strategy for this intractable condition. CASE PRESENTATION: A 30-year-old male was admitted to our hospital in April 2017 and presented with recurrent fever for three months and multiple painless subcutaneous nodules in the abdominal wall. An excision biopsy of the subcutaneous nodules in the abdominal wall revealed NKTCL. The patient was diagnosed with stage IVB NKTCL with skin and multifocal small intestinal involvement according to the imaging results. The first intestinal perforation occurred due to tumor infiltration before the initial treatment. The second intestinal perforation occurred after receiving two cycles of chemotherapy with a modified SMILE regimen. The histone deacetylase inhibitor (HDACi) chidamide was administered as a single-agent therapy after recovery from the second intestinal perforation. Complete remission was achieved. Unfortunately, five months later, the patient was confirmed to have relapsed and received the salvage chemotherapy. The patient suffered from disease progression again after the fourth cycle of chemotherapy. At this point, from May 29, 2018, the patient started to receive injections of the anti-programmed death 1 (PD-1) antibody camrelizumab as a salvage treatment. Two months after the initial anti-PD-1 antibody camrelizumab injection, the response was partial remission. Disease progression was confirmed in March 2021, with a progression-free survival time of 34 months. CONCLUSIONS: NKTCL patients with multifocal small intestine involvement have a high risk of intestinal perforation. The possible etiologies of bowel perforation include tumor infiltration, tumor necrosis in response to therapy, and acute inflammation. The anti-PD-1 antibody camrelizumab may be a new candidate agent for treating this type of intractable NKTCL. Further observations are necessary to identify the efficacy and safety of new agents in the future. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The aim of our study was to determine whether abnormal hyperplasia of chondrocytes occurs in glucocorticoid-induced osteonecrosis of the femoral head (GC-ONFH) using a well-established rat model. MATERIALS AND METHODS: Rats were injected with lipopolysaccharide and methylprednisolone to induce GC-ONFH, while control animals were injected with saline (12 animals per group). Establishment of the disease model was confirmed using micro-computed tomography and hematoxylin-eosin (HE) staining of femoral head tissue sections. Chondrocyte hyperplasia was detected using HE staining and semi-quantitated using toluidine blue and saffron O staining. Expression of the autophagy marker LC3B was assessed in cartilage tissues of femoral head using immunohistochemistry. RESULTS: G C-ONFH a nimals s howed s ignificantly greater area of abnormal chondrocyte hyperplasia in femoral head tissue sections than control animals. They also showed significantly higher expression of LC3B in articular cartilage of the femoral head. CONCLUSIONS: GC-ONFH may be associated with abnormal chondrocyte hyperplasia in articular surface cartilage, which may be related to glucocorticoid-induced overactivation of autophagy. [ABSTRACT FROM AUTHOR]