Gas sensors based on TiO_(2) nanostructured materials for the detection of hazardous gases: A review

Hazardous gases have been strongly associated with being a detriment to human life within the environment The development of a reliable gas sensor with high response and selectivity is of great signifcance for detecting different hazardous gases.TiO_(2) nanomaterials are promising candidates with great potential and excellent per-formance in gas sensor applications,such as hydrogen,acetone,ammonia,and ethanol detection.This review begins with a detailed discussion of the di ferent dimensional morphologies of TiO_(2),whitch affect the gas sensing performance of TiO_(2) sensors.The diverse morphologies of TiO_(2) can easily be tuned by regulating the manufacturing conditions.Meanwhile,they exhibit unique characteristics for detecting gases,including large specific suface area,superior elecron tr ansport rates,extraordinary pemmeability,and active reaction sites,which offer new opportunities to improve the gas sensing properties.In addition,a variety of efforts have been made to functional TiO_(2) nanomaterials to further enhance sensing properties,including TiO_(2)-based composites and light-assisted gas sensors.The enhanced gas sensing mechanisms of multi-component composite nano-materials based on TiO_(2) include loaded noble metals,doped elements,constructed heterojunctions,and com-pounded with other functional materials.Finally,several studies have been summarized to demonstate the compar ative sensing properties of TiO_(2)-based gas sensors.

SnO_(2)nanostructured materials used as gas sensors for the detection of hazardous and flammable gases:A review

SnO_(2)has been extensively used in the detection of various gases.As a gas sensing material,SnO_(2)has excellent physical-chemical properties,high reliability,and short adsorption-desorption time.The application of the traditional SnO_(2)gas sensor is limited due to its higher work-temperature,low gas response,and poor selectivity.Nanomaterials can significantly impact gas-sensitive properties due to the quantum size,surface,and small size effects of nanomaterials.By applying nanotechnology to the preparation of SnO_(2),the SnO_(2)nanomaterial-based sensors could show better performance,which greatly expands the application of SnO_(2)gas sensors.In this review,the preparation method of the SnO_(2)nanostructure,the types of gas detected,and the improvements of SnO_(2)gas-sensing performances via elemental modification are introduced as well as the future development of SnO_(2)is discussed.

USP51/PD-L1/ITGB1-deployed juxtacrine interaction plays a cell-intrinsic role in promoting chemoresistant phenotypes in non-small cell lung cancer

Background:Programmed death ligand 1(PD-L1)has been demonstrated to facilitate tumor progression and therapeutic resistance in an immuneindependent manner.Nevertheless,the function and underlying signaling network(s)of cancer cell-intrinsic PD-L1 action remain largely unknown.Herein,we sought to better understand how ubiquitin-specific peptidase 51(USP51)/PD-L1/integrin beta-1(ITGB1)signaling performs a cell-intrinsic role in mediating chemotherapeutic resistance in non-small cell lung cancer(NSCLC).Methods:Western blotting and flow cytometry were employed for PD-L1 detection in NSCLC cell lines.Coimmunoprecipitation and pulldown analyses,protein deubiquitination assay,tissue microarray,bioinformatic analysis and molecular biology methods were then used to determine the significance of PD-L1 in NSCLC chemoresistance and associated signaling pathways in several different cell lines,mouse models and patient tissue samples.Ubiquitin-7-amido-4-methylcoumarin(Ub-AMC)-based deubiquitinase activity,cellular thermal shift and surface plasmon resonance(SPR)analyses were performed to investigate the activity of USP51 inhibitors.Results:We provided evidence that cancer cell-intrinsic PD-L1 conferred the development of chemoresistance by directly binding to its membrane-bound receptor ITGB1 in NSCLC.At the molecular level,PD-L1/ITGB1 interaction subsequently activated the nuclear factor-kappa B(NF-κB)axis to elicit poor response to chemotherapy.We further determined USP51 as a bona fide deubiquitinase that targeted the deubiquitination and stabilization of the PD-L1 protein in chemoresistant NSCLC cells.Clinically,we found a significant direct relationship between the USP51,PD-L1 and ITGB1 contents in NSCLC patients with chemoresistant potency.The elevated USP51,PD-L1 and ITGB1 levels were strongly associated with worse patient prognosis.Of note,we identified that a flavonoid compound dihydromyricetin(DHM)acted as a potential USP51 inhibitor and rendered NSCLC cells more sensitive to chemotherapy by targeting USP51-dependent PD-L1 ubiquitination and degradation in vitro and in vivo.Conclusions:Together,our results demonstrated that the USP51/PD-L1/ITGB1 network potentially contributes to the malignant progression and therapeutic resistance in NSCLC.This knowledge is beneficial to the future design of advanced cancer therapy.