Dam discharges over spillways are the main reason for the gas-supersaturated water generated in rivers.Local aquatic organisms,especially fish,readily develop gas bubble disease(GBD) in a river with total dissolved ga...Dam discharges over spillways are the main reason for the gas-supersaturated water generated in rivers.Local aquatic organisms,especially fish,readily develop gas bubble disease(GBD) in a river with total dissolved gas supersaturation(TDGS).Sometimes,fish will die after a specific exposure period,which negatively affects the biological equilibrium.In this study,the influence of TDGS on silver carp was explored.Silver carp were exposed to gas-supersaturated water with TDGS levels of 140%,135%,130%,125%,120%,and 110%to test the impact of TDGS.Some silver carp died when the TDGS level was 120%or higher,and all the silver carp exposed to a TDGS level of 140%died within10 h.In comparison with the Chinese sucker,Prenant's schizothoracin,and rock carp,silver carp seem less sensitive to TDGS.In addition,we tested the catalase(CAT) activity in the muscles and gills of silver carp after they were exposed to gas-supersaturated water with a TDGS level of140%.The CAT activity changed with time;it increased first and then decreased until it was lower than the initial CAT activity.The results of this study can provide basic data for developing a standard for environmental evaluation.展开更多
Doublet luminescence from hybrid metal trihalide perovskite semiconductors is observed along with materials processing when high-quality single crystals are obtainable.Yet,the underlying physical mechanism remains poo...Doublet luminescence from hybrid metal trihalide perovskite semiconductors is observed along with materials processing when high-quality single crystals are obtainable.Yet,the underlying physical mechanism remains poorly understood.Here,we report controllable solution-processed crystallization that affords high-quality CH3 NH3 PbBr3 single crystals with atomically flat pristine surfaces.Front-face photoluminescence(PL)shows doublet luminescence components with variable relative intensities depending on the crystal surface conditions.We further find that the low-energy PL component with asymmetric spectral line-shape becomes predominant when the atomically flat crystal surfaces are passivated in the ion-abundant saturated solutions,while poor-quality single crystal with visually rough surface only gives the high-energy PL with symmetric line-shape.The asymmetric spectral line-shape of the low-energy PL matches perfectly with the simulated bandedge emission.Therefore,the low-energy PL component is attributable to the intrinsic bandedge emission from the crystal bulk while the high-energy one to surface-specific emission.Elliott fitting to the absorption data and multi-exponential fitting to the time-resolved photoluminescence traces jointly indicate the coexistence of excitons and electron-hole plasmas in optically excited CH_(3)NH_(3)PbBr_(3)single crystals,thereby catching the physical merit that leads to the occurrence of doublet luminescence.展开更多
Radon is recognized as a powerful tracer of certain geophysical processes in marine and aquatic environments.In the past few decades,the instruments and methods for measuring radon concentration in water have been dev...Radon is recognized as a powerful tracer of certain geophysical processes in marine and aquatic environments.In the past few decades,the instruments and methods for measuring radon concentration in water have been developed to some extent but still lack underwater in-situ measurements.Here we present an in-situ detection equipment for radon-in-water(pulsed ionization chamber(PIC)-radon)to measure dissolved radon in ocean and groundwater settings.The equipment has been successfully deployed in the Jiaozhou Bay in July 2022 and has achieved 14 d of unattended underwater in-situ observation.Then it was successfully placed in a groundwater monitoring well in the Laizhou Bay in November 2022 and monitored radon activities for over 30 d.The results showed that this instrument had a good indication of submarine groundwater discharge.The PIC-radon detector takes advantage of smaller size,lower power consumption,and is barely influenced by humidity,making it particularly suitable for long-term in-situ measurement,especially in harsh environments with limited human care or deployment spaces.展开更多
Twisted graphene systems with flat bands have attracted much attention for they are excellent platforms to research novel quantum phases. Recently, transport measurements about twisted monolayer–bilayer graphene(t MB...Twisted graphene systems with flat bands have attracted much attention for they are excellent platforms to research novel quantum phases. Recently, transport measurements about twisted monolayer–bilayer graphene(t MBG) have shown the existence of correlated states and topological states in this system. However, the direct observations of the band structures and the corresponding spatial distributions are still not sufficient. Here we show that the distributions of flat bands in t MBG host two different modes by scanning tunneling microscopy and spectroscopy(STM/S). By tuning our t MBG device from the empty filling state to the full filling state through the back gate, we observe that the distributions of two flat bands develop from localized mode to delocalized mode. This gate-controlled flat band wavefunction polarization is unique to the t MBG system. Our work suggests that t MBG is promising to simulate both twisted bilayer graphene(TBG) and twisted double bilayer graphene(t DBG) and would be an ideal platform to explore novel moiré physics.展开更多
Triple negative breast cancer(TN BC)is a complex and malignant breast cancer subtype that lacks expression of the estrogen receptor(ER),progesterone receptor(PR)and human epidermal growth factor receptor 2(H ER2),ther...Triple negative breast cancer(TN BC)is a complex and malignant breast cancer subtype that lacks expression of the estrogen receptor(ER),progesterone receptor(PR)and human epidermal growth factor receptor 2(H ER2),thereby making therapeutic targeting difficult.TNBC is generally considered to have high malignancy and poor prognosis.However,patients diagnosed with certain rare histomorphologic subtypes of TNBC have better prognosis than those diagnosed with typical triple negative breast cancer.In addition,with the discovery and development of novel treatment targets such as the androgen receptor(AR),PI3K/AKT/mTOR and AMPK signaling pathways,as well as emerging immunotherapies,the therapeutic options for TNBC are increasing.In this paper,we review the literature on various histological types of TNBC and focus on newly developed therapeutic strategies that target and potentially affect molecular pathways or emerging oncogenes,thus providing a basis for future tailored therapies focused on the mutational aspects of TNBC.展开更多
Microneedle array(MNA)electrodes are an effective solution to achieve high-quality surface biopotential recording without the coordination of conductive gel and are thus very suitable for long-term wearable applicatio...Microneedle array(MNA)electrodes are an effective solution to achieve high-quality surface biopotential recording without the coordination of conductive gel and are thus very suitable for long-term wearable applications.Existing schemes are limited by flexibility,biosafety,and manufacturing costs,which create large barriers for wider applications.Here,we present a novel flexible MNA electrode that can simultaneously achieve flexibility of the substrate to fit a curved body surface,robustness of microneedles to penetrate the skin without fracture,and a simplified process to allow mass production.The compatibility with wearable wireless systems and the short preparation time of the electrodes significantly improves the comfort and convenience of electrophysiological recording.The normalized electrode–skin contact impedance reaches 0.98 kΩcm^(2)at 1 kHz and 1.50 kΩcm^(2)at 10 Hz,a record low value compared to previous reports and approximately 1/250 of the standard electrodes.The morphology,biosafety,and electrical/mechanical properties are fully characterized,and wearable recordings with a high signal-to-noise ratio and low motion artifacts are realized.The first reported clinical study of microneedle electrodes for surface electrophysiological monitoring was conducted in tens of healthy and sleep-disordered subjects with 44 nights of recording(over 8 h per night),providing substantial evidence that the electrodes can be leveraged to substitute for clinical standard electrodes.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.51379136)
文摘Dam discharges over spillways are the main reason for the gas-supersaturated water generated in rivers.Local aquatic organisms,especially fish,readily develop gas bubble disease(GBD) in a river with total dissolved gas supersaturation(TDGS).Sometimes,fish will die after a specific exposure period,which negatively affects the biological equilibrium.In this study,the influence of TDGS on silver carp was explored.Silver carp were exposed to gas-supersaturated water with TDGS levels of 140%,135%,130%,125%,120%,and 110%to test the impact of TDGS.Some silver carp died when the TDGS level was 120%or higher,and all the silver carp exposed to a TDGS level of 140%died within10 h.In comparison with the Chinese sucker,Prenant's schizothoracin,and rock carp,silver carp seem less sensitive to TDGS.In addition,we tested the catalase(CAT) activity in the muscles and gills of silver carp after they were exposed to gas-supersaturated water with a TDGS level of140%.The CAT activity changed with time;it increased first and then decreased until it was lower than the initial CAT activity.The results of this study can provide basic data for developing a standard for environmental evaluation.
基金Project supported by the National Natural Science Foundation of China(Grant No.51872038)。
文摘Doublet luminescence from hybrid metal trihalide perovskite semiconductors is observed along with materials processing when high-quality single crystals are obtainable.Yet,the underlying physical mechanism remains poorly understood.Here,we report controllable solution-processed crystallization that affords high-quality CH3 NH3 PbBr3 single crystals with atomically flat pristine surfaces.Front-face photoluminescence(PL)shows doublet luminescence components with variable relative intensities depending on the crystal surface conditions.We further find that the low-energy PL component with asymmetric spectral line-shape becomes predominant when the atomically flat crystal surfaces are passivated in the ion-abundant saturated solutions,while poor-quality single crystal with visually rough surface only gives the high-energy PL with symmetric line-shape.The asymmetric spectral line-shape of the low-energy PL matches perfectly with the simulated bandedge emission.Therefore,the low-energy PL component is attributable to the intrinsic bandedge emission from the crystal bulk while the high-energy one to surface-specific emission.Elliott fitting to the absorption data and multi-exponential fitting to the time-resolved photoluminescence traces jointly indicate the coexistence of excitons and electron-hole plasmas in optically excited CH_(3)NH_(3)PbBr_(3)single crystals,thereby catching the physical merit that leads to the occurrence of doublet luminescence.
基金The National Natural Science Foundation of China under contract Nos U22A20580 and 42130410the Fundamental Research Funds for the Central Universities under contract No.202341002the Pilot Project for the Integration of Science,Education,and Industry under contract No.2022PY069.
文摘Radon is recognized as a powerful tracer of certain geophysical processes in marine and aquatic environments.In the past few decades,the instruments and methods for measuring radon concentration in water have been developed to some extent but still lack underwater in-situ measurements.Here we present an in-situ detection equipment for radon-in-water(pulsed ionization chamber(PIC)-radon)to measure dissolved radon in ocean and groundwater settings.The equipment has been successfully deployed in the Jiaozhou Bay in July 2022 and has achieved 14 d of unattended underwater in-situ observation.Then it was successfully placed in a groundwater monitoring well in the Laizhou Bay in November 2022 and monitored radon activities for over 30 d.The results showed that this instrument had a good indication of submarine groundwater discharge.The PIC-radon detector takes advantage of smaller size,lower power consumption,and is barely influenced by humidity,making it particularly suitable for long-term in-situ measurement,especially in harsh environments with limited human care or deployment spaces.
基金support from the National Key R&D Program of China (Grant No. 2019YFA0307800)Beijing Natural Science Foundation (Grant No. Z190011)+1 种基金the National Natural Science Foundation of China (Grant No. 11974347)Fundamental Research Funds for the Central Universities。
文摘Twisted graphene systems with flat bands have attracted much attention for they are excellent platforms to research novel quantum phases. Recently, transport measurements about twisted monolayer–bilayer graphene(t MBG) have shown the existence of correlated states and topological states in this system. However, the direct observations of the band structures and the corresponding spatial distributions are still not sufficient. Here we show that the distributions of flat bands in t MBG host two different modes by scanning tunneling microscopy and spectroscopy(STM/S). By tuning our t MBG device from the empty filling state to the full filling state through the back gate, we observe that the distributions of two flat bands develop from localized mode to delocalized mode. This gate-controlled flat band wavefunction polarization is unique to the t MBG system. Our work suggests that t MBG is promising to simulate both twisted bilayer graphene(TBG) and twisted double bilayer graphene(t DBG) and would be an ideal platform to explore novel moiré physics.
基金the National Natural Science Foundation of China(Grant No.81172532).
文摘Triple negative breast cancer(TN BC)is a complex and malignant breast cancer subtype that lacks expression of the estrogen receptor(ER),progesterone receptor(PR)and human epidermal growth factor receptor 2(H ER2),thereby making therapeutic targeting difficult.TNBC is generally considered to have high malignancy and poor prognosis.However,patients diagnosed with certain rare histomorphologic subtypes of TNBC have better prognosis than those diagnosed with typical triple negative breast cancer.In addition,with the discovery and development of novel treatment targets such as the androgen receptor(AR),PI3K/AKT/mTOR and AMPK signaling pathways,as well as emerging immunotherapies,the therapeutic options for TNBC are increasing.In this paper,we review the literature on various histological types of TNBC and focus on newly developed therapeutic strategies that target and potentially affect molecular pathways or emerging oncogenes,thus providing a basis for future tailored therapies focused on the mutational aspects of TNBC.
基金supported by the China Capital Health Research and Development of Special (No. 2018-14111)the National Natural Science Foundation of China (grant No. 62004007 and No. 82027805)the China Postdoctoral Science Foundation Grant (No. 2021M700258)
文摘Microneedle array(MNA)electrodes are an effective solution to achieve high-quality surface biopotential recording without the coordination of conductive gel and are thus very suitable for long-term wearable applications.Existing schemes are limited by flexibility,biosafety,and manufacturing costs,which create large barriers for wider applications.Here,we present a novel flexible MNA electrode that can simultaneously achieve flexibility of the substrate to fit a curved body surface,robustness of microneedles to penetrate the skin without fracture,and a simplified process to allow mass production.The compatibility with wearable wireless systems and the short preparation time of the electrodes significantly improves the comfort and convenience of electrophysiological recording.The normalized electrode–skin contact impedance reaches 0.98 kΩcm^(2)at 1 kHz and 1.50 kΩcm^(2)at 10 Hz,a record low value compared to previous reports and approximately 1/250 of the standard electrodes.The morphology,biosafety,and electrical/mechanical properties are fully characterized,and wearable recordings with a high signal-to-noise ratio and low motion artifacts are realized.The first reported clinical study of microneedle electrodes for surface electrophysiological monitoring was conducted in tens of healthy and sleep-disordered subjects with 44 nights of recording(over 8 h per night),providing substantial evidence that the electrodes can be leveraged to substitute for clinical standard electrodes.
