MFPL:Multi-Frequency Phase Difference Combination Based Device-Free Localization

With the popularity of indoor wireless network,device-free indoor localization has attracted more and more attention.Unlike device-based localization where the target is required to carry an active transmitter,their frequent signal scanning consumes a large amount of energy,which is inconvenient for devices with limited energy.In this work,we propose the MFPL,device-free localization(DFL)system based on WiFi distance measurement.First,we combine multi-subcarrier characteristic of Channel State Information(CSI)with classical Fresnel reflection model to get the linear relationship between the change of the length of reflection path and the subcarrier phase difference.Then we calculate the Fresnel phase difference between subcarrier pairs with different spacing from CSI amplitude time series.Finally,we get the change of the length of the reflection path caused by target moving to achieve distance measurement and localization.Using a combination of subcarriers with different spacing to achieve distance measurement effectively broadens the maximum unambiguous distance of the system.To solve the complex non-linear problem of the intersection of two elliptic equations,we introduce Newton's method to transform the non-linear problem into a linear one.The effectiveness of our approach is verified using commodity WiFi infrastructures.The experimental results show our method achieves a median error of 0.87 m in actual indoor environment.

Cell cycle-related kinase reprograms the liver immune microenvironment to promote cancer metastasis

The liver is an immunologically tolerant organ and a common metastatic site of multiple cancer types.Although a role for cancer cell invasion programs has been well characterized,whether and how liver-intrinsic factors drive metastatic spread is incompletely understood.Here,we show that aberrantly activated hepatocyte-intrinsic cell cycle-related kinase(CCRK)signaling in chronic liver diseases is critical for cancer metastasis by reprogramming an immunosuppressive microenvironment.Using an inducible liverspecific transgenic model,we found that CCRK overexpression dramatically increased both B16F10 melanoma and MC38 colorectal cancer(CRC)metastasis to the liver,which was highly infiltrated by polymorphonuclear-myeloid-derived suppressor cells(PMNMDSCs)and lacking natural killer T(NKT)cells.Depletion of PMN-MDSCs in CCRK transgenic mice restored NKT cell levels and their interferon gamma production and reduced liver metastasis to 2.7% and 0.7%(metastatic tumor weights)in the melanoma and CRC models,respectively.Mechanistically,CCRK activated nuclear factor-kappa B(NF-κB)signaling to increase the PMN-MDSC trafficking chemokine C-X-C motif ligand 1(CXCL1),which was positively correlated with liver-infiltrating PMN-MDSC levels in CCRK transgenic mice.Accordingly,CRC liver metastasis patients exhibited hyperaaivation of hepatic CCRK/NF-κB/CXCL1 signaling,which was associated with accumulation of PMN-MDSCs and paucity of NKT cells compared to healthy liver transplantation donors.In summary,this study demonstrates that immunosuppressive reprogramming by hepatic CCRK signaling undermines antimetastatic immunosurveillance.Our findings offer new mechanistic insights and therapeutic targets for liver metastasis intervention.

Aberrant cholesterol metabolic signaling impairs antitumor immunosurveillance through natural killer T cell dysfunction in obese liver

Obesity is a major risk factor for cancers including hepatocellular carcinoma(HCC)that develops from a background of non-alcoholic fatty liver disease(NAFLD).Hypercholesterolemia is a common comorbidity of obesity.Although cholesterol biosynthesis mainly occurs in the liver,its role in HCC development of obese people remains obscure.Using high-fat high-carbohydrate diet-associated orthotopic and spontaneous NAFLD-HCC mouse models,we found that hepatic cholesterol accumulation in obesity selectively suppressed natural killer T(NKT)cell-mediated antitumor immunosurveillance.Transcriptome analysis of human liver revealed aberrant cholesterol metabolism and NKT cell dysfunction in NAFLD patients.Notably,cholesterol-lowering rosuvastatin restored NKT expansion and cytotoxicity to prevent obesogenic diet-promoted HCC development.Moreover,suppression of hepatic cholesterol biosynthesis by a mammalian target of rapamycin(mTOR)inhibitor vistusertib preceded tumor regression,which was abolished by NKT inactivation but not CD8^(+)T cell depletion.Mechanistically,sterol regulatory element-binding protein 2(SREBP2)-driven excessive cholesterol production from hepatocytes induced lipid peroxide accumulation and deficient cytotoxicity in NKT cells,which were supported by findings in people with obesity,NAFLD and NAFLD-HCC.This study highlights mTORC1/SREBP2/cholesterol-mediated NKT dysfunction in the tumor-promoting NAFLD liver microenvironment,providing intervention strategies that invigorating NKT cells to control HCC in the obesity epidemic.