In current research on task offloading and resource scheduling in vehicular networks,vehicles are commonly assumed to maintain constant speed or relatively stationary states,and the impact of speed variations on task ...In current research on task offloading and resource scheduling in vehicular networks,vehicles are commonly assumed to maintain constant speed or relatively stationary states,and the impact of speed variations on task offloading is often overlooked.It is frequently assumed that vehicles can be accurately modeled during actual motion processes.However,in vehicular dynamic environments,both the tasks generated by the vehicles and the vehicles’surroundings are constantly changing,making it difficult to achieve real-time modeling for actual dynamic vehicular network scenarios.Taking into account the actual dynamic vehicular scenarios,this paper considers the real-time non-uniform movement of vehicles and proposes a vehicular task dynamic offloading and scheduling algorithm for single-task multi-vehicle vehicular network scenarios,attempting to solve the dynamic decision-making problem in task offloading process.The optimization objective is to minimize the average task completion time,which is formulated as a multi-constrained non-linear programming problem.Due to the mobility of vehicles,a constraint model is applied in the decision-making process to dynamically determine whether the communication range is sufficient for task offloading and transmission.Finally,the proposed vehicular task dynamic offloading and scheduling algorithm based on muti-agent deep deterministic policy gradient(MADDPG)is applied to solve the optimal solution of the optimization problem.Simulation results show that the algorithm proposed in this paper is able to achieve lower latency task computation offloading.Meanwhile,the average task completion time of the proposed algorithm in this paper can be improved by 7.6%compared to the performance of the MADDPG scheme and 51.1%compared to the performance of deep deterministic policy gradient(DDPG).展开更多
Previous study revealed that ferritin heavy chain-1(FTH1)could regulate ferritinophagy and affect intracellular Fe^(+)content in various tumors,while its N6-methyladenosine(m6A)RNA methylation was closely related the ...Previous study revealed that ferritin heavy chain-1(FTH1)could regulate ferritinophagy and affect intracellular Fe^(+)content in various tumors,while its N6-methyladenosine(m6A)RNA methylation was closely related the prognosis of ovarian cancer patients.However,little is known about the role of FTH1 m6A methylation in ovarian cancer(OC)and its possible action mechanisms.In this study we constructed FTH1 m6A methylation regulatory pathway(LncRNA CACNA1G-AS1/IGF2BP1)according to related bioinformatics analysis and research,through clinical sample detections we found that these pathway regulatory factors were significantly up-regulated in ovarian cancer tissues,and their expression levels were closely related to the malignant phenotype of ovarian cancer.In vitro cell experiments showed that LncRNA CACNA1G-AS1 could up-regulate FTH1 expression through IGF2BP1 axis,thus inhibited ferroptosis by regulating ferritinophagy,and finally promoted proliferation and migration in ovarian cancer cells.Tumor-bearing mice studies showed that the knock-down of LncRNA CACNA1G-AS1 could inhibited the tumorigenesis of ovarian cancer cells in vivo condition.Our results demonstrated that LncRNA CACNA1G-AS1 could promote the malignant phenotypes of ovarian cancer cells through FTH1-IGF2BP1 regulated ferroptosis.展开更多
Objective: To observe the efficacy and safety of topical imiquimod 5% cream in the treatment of uncomplicated infantile hemangiomas (IHs). Methods: A total of 68 IHs were treated with topical imiquimod 5% cream. A...Objective: To observe the efficacy and safety of topical imiquimod 5% cream in the treatment of uncomplicated infantile hemangiomas (IHs). Methods: A total of 68 IHs were treated with topical imiquimod 5% cream. Among them, 36 were superficial, 22 were mixed, and 10 were deep. The size of IHs ranged from 1.0 cm × 1.5 cm to an area of a whole forearm. All the hemangiomas were in a proliferative stage. Imiquimod was applied 3 times weekly in 44 patients and 5 times weekly in 24 patients for up to 36 weeks. Results: All superficial IHs improved, and 18 achieved complete clinical resolution, 10 had excellent improvement, 5 showed moderate improvements, and 3 patients displayed minimal improvement. Two mixed IHs showed excellent improvement, 3 showed moderate improvement and 5 manifested minimal improvements. The remaining 12 mixed IHs and all deep IHs did not respond to the therapy. The total incidence of local adverse events was 58.82%(40/68), which included erythema or edema, local itching, incrustation or peeling, erosion or ulceration, although most of these were mild to moderate reactions and did not affect the treatment. Scarring occurred in 2 mixed IHs. No systemic side effects developed. Conclusion: Imiquimod 5% cream may be a safe and effective alternative for the treatment of superficial IHs and some mixed IHs in which the superficial component predominates. An appropriate treatment duration for proliferative IHs treated with this therapy may be 24 weeks. Some local adverse events, such as crusting and erosion with possible scarfing potential may occur and should be addressed by prompt, but temporary, discontinuation of the imiquimod. Topical imiquimod 5% cream can be prudently used in the treatment of IHs larger than 5.0 cm × 5.0 cm in newborns and infants less than 6 months of age. To our knowledge, this is the largest IH group treated with imiquimod that has been reported in the literature to date.展开更多
1.Introduction Oil crops such as soybeans,sunflower,canola,rapeseed,and peanuts play a vital role in the agricultural economy,second only to food crops in terms of area and yield.Vegetable oil is known for its high en...1.Introduction Oil crops such as soybeans,sunflower,canola,rapeseed,and peanuts play a vital role in the agricultural economy,second only to food crops in terms of area and yield.Vegetable oil is known for its high energy density,containing approximately 2.25 times more calories per unit mass than carbohydrates or protein.Therefore,vegetable oil is an important source of energy and provides a variety of fatty acids necessary for human health.展开更多
Hospital-acquired infection(HAI)is a significant global health concern,elevating the risks of morbidity and imposing a substantial socioeconomic burden.To enhance the management of HAI,particularly in the aftermath of...Hospital-acquired infection(HAI)is a significant global health concern,elevating the risks of morbidity and imposing a substantial socioeconomic burden.To enhance the management of HAI,particularly in the aftermath of the coronavirus disease 2019(COVID-19)pandemic,the Guangdong Second Provincial General Hospital(GD2H)has launched a new system called Intelligent Forest Hospital(IFH).Leveraging advancements in artificial intelligence,5G technology,and cloud networking,the IFH implements customized indoor air quality(IAQ)control strategies tailored to different medical settings.It utilizes various intelligent disinfection devices and air purification systems.The IFH features a dynamic 3D hospital model with real-time monitoring of crucial IAQ parameters and a risk assessment ranking for clinical departments,providing timely risk alerts,communication prompts,and automatic disinfection processes.The IFH aims to effectively mitigate HAI post-COVID-19 and other future pandemics,ensuring a safe and pleasant environment for patients,hospital staff,and visitors.展开更多
With the continuous appearance and expansion of high-strength hydrogels in emerging fields such as industry,medicine,and green development,the synthesis and application of high-strength hydrogels have developed dramat...With the continuous appearance and expansion of high-strength hydrogels in emerging fields such as industry,medicine,and green development,the synthesis and application of high-strength hydrogels have developed dramatically and achieved remarkable results from the aspects of raw materials,preparation methods,and reinforcement mechanisms.However,there is still a lack of systematic reviews on high-strength hydrogels.Herein,we first discuss the advantages of natural and synthetic materials,and the characteristics of high-strength hydrogels prepared from different raw materials;we then expound on the influence mechanism of physical interactions or chemical bonds on the strength of the hydrogel from three aspects:physical cross-linking,chemical cross-linking,and dynamic chemical cross-linking;at last,we systematically expound the strengthening strategies,including double network/multi-network,nanocomposite,topology,supramolecular polymerization,and characteristics and strengthening mechanisms of such high-strength hydrogels.In addition,based on the development status of high-strength hydrogels,we combined the application requirements and the existing drawbacks of high-strength hydrogels to propose their possible development directions in the future.展开更多
Hexagonal-phase NaYF_(4)(β-NaYF_(4))has been acknowledged to be one of the most efficient doping hosts to prepare bright lanthanide-doped luminescent nano-bioprobes for various biomedical applications.However,to date...Hexagonal-phase NaYF_(4)(β-NaYF_(4))has been acknowledged to be one of the most efficient doping hosts to prepare bright lanthanide-doped luminescent nano-bioprobes for various biomedical applications.However,to date,it remains a great challenge to synthesize ultra-bright lanthanide-dopedβ-NaYF_(4)nano-bioprobes under a low reaction temperature by using conventional synthetic methods.Herein,we first develop an acetic acid(HAc)-mediated coprecipitation method for the preparation of ultrabright lanthanide-dopedβ-NaYF_(4)nanoprobes under a low reaction temperature at 200℃.Based on a series of comparative spectroscopic investigations,we show that the use of HAc in the reaction environment can not only promote the rapidα-βphase transformation of NaYF_(4)host at 200℃ within 1 h but also boost the absolute photoluminescence quantum yield(PLQY)of NaYF_(4)nanocrystals to 30.68%for near-infrared emission and to 3.79%for upconversion luminescence,both of which are amongst the highest values for diverse lanthanide-doped luminescent nanocrystals ever reported.By virtue of their superior nearinfrared luminescence,we achieve optical-guided dynamic vasculature imaging in vivo of the whole body at a high spatial resolution(23.8μm)under 980 nm excitation,indicating its potential for the diagnosis and treatment evaluation of vasculaturerelated diseases.展开更多
The problem of imaging through thick scattering media is encountered in many disciplines of science,ranging from mesoscopic physics to astronomy.Photons become diffusive after propagating through a scattering medium w...The problem of imaging through thick scattering media is encountered in many disciplines of science,ranging from mesoscopic physics to astronomy.Photons become diffusive after propagating through a scattering medium with an optical thickness of over 10 times the scattering mean free path.As a result,no image but only noise-like patterns can be directly formed.We propose a hybrid neural network for computational imaging through such thick scattering media,demonstrating the reconstruction of image information from various targets hidden behind a white polystyrene slab of 3 mm in thickness or 13.4 times the scattering mean free path.We also demonstrate that the target image can be retrieved with acceptable quality from a very small fraction of its scattered pattern,suggesting that the speckle pattern produced in this way is highly redundant.This leads to a profound question of how the information of the target being encoded into the speckle is to be addressed in future studies.展开更多
Magnetic fields are known as clean,economic,and effective tools to modify band and magnetic structures of materials.When coupled with catalytic processes such as the hydrogen evolution reaction(HER),they have the pote...Magnetic fields are known as clean,economic,and effective tools to modify band and magnetic structures of materials.When coupled with catalytic processes such as the hydrogen evolution reaction(HER),they have the potential to control catalytic efficiency.Herein,we studied the magnetic response of a series of materials as HER catalysts,specifically ferromagnetic Co_(2)VGa,Co_(2)MnGa,and Ni,ferrimagnetic Mn_(2)CoGa,and paramagnetic Pt.展开更多
Maltose is a natural α-(1,4)-linked disaccharide with wide applications in food industries and microbial fermentation. However,maltose has scarcely been used for in vitro biosynthesis, possibly because its phosphoryl...Maltose is a natural α-(1,4)-linked disaccharide with wide applications in food industries and microbial fermentation. However,maltose has scarcely been used for in vitro biosynthesis, possibly because its phosphorylation by maltose phosphorylase (MP)yields β-glucose 1-phosphate (β-G1P) that cannot be utilized by α-phosphoglucomutase (α-PGM) commonly found in in vitrosynthetic enzymatic biosystems previously constructed by our group. Herein, we designed an in vitro synthetic enzymaticreaction module comprised of MP, β-phosphoglucomutase (β-PGM), and polyphosphate glucokinase (PPGK) for thestoichiometric conversion of each maltose molecule to two glucose 6-phosphate (G6P) molecules. Based on this syntheticmodule, we further constructed two in vitro synthetic biosystems to produce bioelectricity and fructose 1,6-diphosphate (FDP),respectively. The 14-enzyme biobattery achieved a Faraday efficiency of 96.4% and a maximal power density of 0.6mW/cm^(2),whereas the 5-enzyme in vitro FDP-producing biosystem yielded 187.0mM FDP from 50 g/L (139mM) maltose by adopting afed-batch substrate feeding strategy. Our study not only suggests new application scenarios for maltose but also provides novelstrategies for the high-efficient production of bioelectricity and value-added biochemicals.展开更多
Trivalent lanthanide(Ln^(3+))-doped luminescent nanoparticles(NPs)have been extensively investigated as deep-tissue-penetration visual bioimaging agents owing to their exceptional upconversion and near-infrared(NIR)lu...Trivalent lanthanide(Ln^(3+))-doped luminescent nanoparticles(NPs)have been extensively investigated as deep-tissue-penetration visual bioimaging agents owing to their exceptional upconversion and near-infrared(NIR)luminescence upon irradiation of NIR light.However,in most cases,the power density of irradiation used for in vivo biological imaging is much higher than that of the reported maximum permissible exposure(MPE)value of NIR light,which inevitably does great damage to the living organisms under study and thus impedes the plausible clinical applications.Herein,by using a facile syringe pump-aided shell epitaxial growth method,we construct for the first time a new class of Ln^(3+)-doped KMgF_(3):Yb/Er@KMgF_(3)core-shell NPs that can be activated by utilizing a 980-nm xenon lamp or diode laser with an ultralow excitation power density down to 0.08 mW cm^(−2),a value that is approximately 4 orders of magnitude lower than the MPE value set by the American National Standards Institute(ANSI)for safe bioimaging in vivo.By combining the comparative spectroscopic investigations with atomic-resolved spherical aberration corrected transmission electron microscopy(AC-TEM)characterization,we find that the reduced crystallographic defects are the primary cause underlying such an ultralow-power-excitable feature of the KMgF_(3):Yb/Er@KMgF_(3)core-shell NPs.And,by the same token,the resultant KMgF_(3):Yb/Er@KMgF_(3)core-shell NPs also exhibit an anomalous thermo-enhanced photoluminescence(PL)behavior coupled with an excellent photothermal stability that cannot occur in other Ln^(3+)-doped core-shell NPs.These findings described here unambiguously pave a new way to prepare high-quality Ln^(3+)-doped luminescent NPs with desirable ultralow-power-excitable capability and photothermal stability for future biomedical applications.展开更多
The difficulties in designing high-performance hydrogen evolution reaction(HER)catalysts lie in the manipulation of adsorption behaviors of transition metals(TMs).Topological chiral semimetals with super-long Fermi ar...The difficulties in designing high-performance hydrogen evolution reaction(HER)catalysts lie in the manipulation of adsorption behaviors of transition metals(TMs).Topological chiral semimetals with super-long Fermi arc surface states provide an ideal platform for engineering the catalytic performance of TMs through the metal-support interaction.We found the adsorption trends of TMs can be modified significantly when deposited at the surface of the PdGa chiral crystal.The electron transfer from the TMs to the surface states of the PdGa reshapes the d band structure of TMs and weakens the hydrogen intermediate bonding.Especially,W/PdGa is expected to be a good HER catalyst with close to zero Gibbs free energy.Experimentally,we found a Pt-like exchange current density and tumover frequency when depositing W atoms at the PdGa nanostructures surface.The findings provide a way to develop high-efficient electrocatalysts by the interplay between topological surface states and metal-support interaction.展开更多
Highly conductive topological semimetals with exotic electronic structures offer fertile ground for the investigation of the electrical and thermal transport behavior of quasiparticles.Here,we find that the layer-stru...Highly conductive topological semimetals with exotic electronic structures offer fertile ground for the investigation of the electrical and thermal transport behavior of quasiparticles.Here,we find that the layer-structured Dirac semimetal PtSn4 exhibits a largely suppressed thermal conductivity under a magnetic field.At low temperatures,a dramatic decrease in the thermal conductivity of PtSn4 by more than two orders of magnitude is obtained at 9 T.Moreover,PtSn_(4)shows both strong longitudinal and transverse thermoelectric responses under a magnetic field.Large power factor and Nernst power factor of approximately 80-100μW·cm^(-1)·K^(-2)are obtained around 15K in various magnetic fields.As a result,the thermoelectric figure of merit zT is strongly enhanced by more than 30 times,compared to that without a magnetic field.This work provides a paradigm for the decoupling of the electron and hole transport behavior of highly conductive topological semimetals and is helpful for developing topological semimetals for thermoelectric energy conversion.展开更多
文摘In current research on task offloading and resource scheduling in vehicular networks,vehicles are commonly assumed to maintain constant speed or relatively stationary states,and the impact of speed variations on task offloading is often overlooked.It is frequently assumed that vehicles can be accurately modeled during actual motion processes.However,in vehicular dynamic environments,both the tasks generated by the vehicles and the vehicles’surroundings are constantly changing,making it difficult to achieve real-time modeling for actual dynamic vehicular network scenarios.Taking into account the actual dynamic vehicular scenarios,this paper considers the real-time non-uniform movement of vehicles and proposes a vehicular task dynamic offloading and scheduling algorithm for single-task multi-vehicle vehicular network scenarios,attempting to solve the dynamic decision-making problem in task offloading process.The optimization objective is to minimize the average task completion time,which is formulated as a multi-constrained non-linear programming problem.Due to the mobility of vehicles,a constraint model is applied in the decision-making process to dynamically determine whether the communication range is sufficient for task offloading and transmission.Finally,the proposed vehicular task dynamic offloading and scheduling algorithm based on muti-agent deep deterministic policy gradient(MADDPG)is applied to solve the optimal solution of the optimization problem.Simulation results show that the algorithm proposed in this paper is able to achieve lower latency task computation offloading.Meanwhile,the average task completion time of the proposed algorithm in this paper can be improved by 7.6%compared to the performance of the MADDPG scheme and 51.1%compared to the performance of deep deterministic policy gradient(DDPG).
基金Suzhou Youth Project of Promoting Health through Science and Education,Grant ID:KJXW2022010.
文摘Previous study revealed that ferritin heavy chain-1(FTH1)could regulate ferritinophagy and affect intracellular Fe^(+)content in various tumors,while its N6-methyladenosine(m6A)RNA methylation was closely related the prognosis of ovarian cancer patients.However,little is known about the role of FTH1 m6A methylation in ovarian cancer(OC)and its possible action mechanisms.In this study we constructed FTH1 m6A methylation regulatory pathway(LncRNA CACNA1G-AS1/IGF2BP1)according to related bioinformatics analysis and research,through clinical sample detections we found that these pathway regulatory factors were significantly up-regulated in ovarian cancer tissues,and their expression levels were closely related to the malignant phenotype of ovarian cancer.In vitro cell experiments showed that LncRNA CACNA1G-AS1 could up-regulate FTH1 expression through IGF2BP1 axis,thus inhibited ferroptosis by regulating ferritinophagy,and finally promoted proliferation and migration in ovarian cancer cells.Tumor-bearing mice studies showed that the knock-down of LncRNA CACNA1G-AS1 could inhibited the tumorigenesis of ovarian cancer cells in vivo condition.Our results demonstrated that LncRNA CACNA1G-AS1 could promote the malignant phenotypes of ovarian cancer cells through FTH1-IGF2BP1 regulated ferroptosis.
基金supported by Science and Technology Foundation of shaanxi Province(2005K13-G6)
文摘Objective: To observe the efficacy and safety of topical imiquimod 5% cream in the treatment of uncomplicated infantile hemangiomas (IHs). Methods: A total of 68 IHs were treated with topical imiquimod 5% cream. Among them, 36 were superficial, 22 were mixed, and 10 were deep. The size of IHs ranged from 1.0 cm × 1.5 cm to an area of a whole forearm. All the hemangiomas were in a proliferative stage. Imiquimod was applied 3 times weekly in 44 patients and 5 times weekly in 24 patients for up to 36 weeks. Results: All superficial IHs improved, and 18 achieved complete clinical resolution, 10 had excellent improvement, 5 showed moderate improvements, and 3 patients displayed minimal improvement. Two mixed IHs showed excellent improvement, 3 showed moderate improvement and 5 manifested minimal improvements. The remaining 12 mixed IHs and all deep IHs did not respond to the therapy. The total incidence of local adverse events was 58.82%(40/68), which included erythema or edema, local itching, incrustation or peeling, erosion or ulceration, although most of these were mild to moderate reactions and did not affect the treatment. Scarring occurred in 2 mixed IHs. No systemic side effects developed. Conclusion: Imiquimod 5% cream may be a safe and effective alternative for the treatment of superficial IHs and some mixed IHs in which the superficial component predominates. An appropriate treatment duration for proliferative IHs treated with this therapy may be 24 weeks. Some local adverse events, such as crusting and erosion with possible scarfing potential may occur and should be addressed by prompt, but temporary, discontinuation of the imiquimod. Topical imiquimod 5% cream can be prudently used in the treatment of IHs larger than 5.0 cm × 5.0 cm in newborns and infants less than 6 months of age. To our knowledge, this is the largest IH group treated with imiquimod that has been reported in the literature to date.
基金supported by the Key Research and Development Program of Shandong Province(2021LZGC026)。
文摘1.Introduction Oil crops such as soybeans,sunflower,canola,rapeseed,and peanuts play a vital role in the agricultural economy,second only to food crops in terms of area and yield.Vegetable oil is known for its high energy density,containing approximately 2.25 times more calories per unit mass than carbohydrates or protein.Therefore,vegetable oil is an important source of energy and provides a variety of fatty acids necessary for human health.
基金Supported by the Science Foundation of Guangdong Second Provincial General Hospital(number:YY2018-002,recipient:GL).
文摘Hospital-acquired infection(HAI)is a significant global health concern,elevating the risks of morbidity and imposing a substantial socioeconomic burden.To enhance the management of HAI,particularly in the aftermath of the coronavirus disease 2019(COVID-19)pandemic,the Guangdong Second Provincial General Hospital(GD2H)has launched a new system called Intelligent Forest Hospital(IFH).Leveraging advancements in artificial intelligence,5G technology,and cloud networking,the IFH implements customized indoor air quality(IAQ)control strategies tailored to different medical settings.It utilizes various intelligent disinfection devices and air purification systems.The IFH features a dynamic 3D hospital model with real-time monitoring of crucial IAQ parameters and a risk assessment ranking for clinical departments,providing timely risk alerts,communication prompts,and automatic disinfection processes.The IFH aims to effectively mitigate HAI post-COVID-19 and other future pandemics,ensuring a safe and pleasant environment for patients,hospital staff,and visitors.
基金supported by the National Natural Science Foundation of China(No.52003216)the China Postdoctoral Science Foundation(Nos.2021M693007 and 2022M712506)+1 种基金the Chongqing Natural Science Foundation of China(No.cstc2020jcyj-msxmX0784)the Project of Supporting Young Talents in Shaanxi University Science and Technology Association(No.202044).
文摘With the continuous appearance and expansion of high-strength hydrogels in emerging fields such as industry,medicine,and green development,the synthesis and application of high-strength hydrogels have developed dramatically and achieved remarkable results from the aspects of raw materials,preparation methods,and reinforcement mechanisms.However,there is still a lack of systematic reviews on high-strength hydrogels.Herein,we first discuss the advantages of natural and synthetic materials,and the characteristics of high-strength hydrogels prepared from different raw materials;we then expound on the influence mechanism of physical interactions or chemical bonds on the strength of the hydrogel from three aspects:physical cross-linking,chemical cross-linking,and dynamic chemical cross-linking;at last,we systematically expound the strengthening strategies,including double network/multi-network,nanocomposite,topology,supramolecular polymerization,and characteristics and strengthening mechanisms of such high-strength hydrogels.In addition,based on the development status of high-strength hydrogels,we combined the application requirements and the existing drawbacks of high-strength hydrogels to propose their possible development directions in the future.
基金This work was supported by the Fund of Fujian Science&Technology Innovation Laboratory for Optoelectronic Information(No.2020ZZ114)the Key Research Program of Frontier Science CAS(No.QYZDY-SSW-SLH025)+2 种基金the National Natural Science Foundation of China(Nos.21871256 and 12204481)the Natural Science Foundation of Fujian Province(No.2022J01211422)Fund of Advanced Energy Science and Technology Guangdong Laboratory(No.DJLTN0200/DJLTN0240).
文摘Hexagonal-phase NaYF_(4)(β-NaYF_(4))has been acknowledged to be one of the most efficient doping hosts to prepare bright lanthanide-doped luminescent nano-bioprobes for various biomedical applications.However,to date,it remains a great challenge to synthesize ultra-bright lanthanide-dopedβ-NaYF_(4)nano-bioprobes under a low reaction temperature by using conventional synthetic methods.Herein,we first develop an acetic acid(HAc)-mediated coprecipitation method for the preparation of ultrabright lanthanide-dopedβ-NaYF_(4)nanoprobes under a low reaction temperature at 200℃.Based on a series of comparative spectroscopic investigations,we show that the use of HAc in the reaction environment can not only promote the rapidα-βphase transformation of NaYF_(4)host at 200℃ within 1 h but also boost the absolute photoluminescence quantum yield(PLQY)of NaYF_(4)nanocrystals to 30.68%for near-infrared emission and to 3.79%for upconversion luminescence,both of which are amongst the highest values for diverse lanthanide-doped luminescent nanocrystals ever reported.By virtue of their superior nearinfrared luminescence,we achieve optical-guided dynamic vasculature imaging in vivo of the whole body at a high spatial resolution(23.8μm)under 980 nm excitation,indicating its potential for the diagnosis and treatment evaluation of vasculaturerelated diseases.
基金This study was supported by the Key Research Program of Frontier Sciences,Chinese Academy of Sciences(Grant No.QYZDB-SSW-JSC002)Sino-German Center for Sino-German Cooperation Group(Grant No.GZ 1391).
文摘The problem of imaging through thick scattering media is encountered in many disciplines of science,ranging from mesoscopic physics to astronomy.Photons become diffusive after propagating through a scattering medium with an optical thickness of over 10 times the scattering mean free path.As a result,no image but only noise-like patterns can be directly formed.We propose a hybrid neural network for computational imaging through such thick scattering media,demonstrating the reconstruction of image information from various targets hidden behind a white polystyrene slab of 3 mm in thickness or 13.4 times the scattering mean free path.We also demonstrate that the target image can be retrieved with acceptable quality from a very small fraction of its scattered pattern,suggesting that the speckle pattern produced in this way is highly redundant.This leads to a profound question of how the information of the target being encoded into the speckle is to be addressed in future studies.
基金supported by the European Research Council(ERC Advanced grant no.742068‘TOPMAT’)the DFG through SFB 1143(project ID.247310070)the Würzburg-Dresden Cluster of Excellence on Complexity and Topology in Quantum Matter ct.qmat(EXC2147,project ID 39085490),and DFG project HE 3543/35–1.
文摘Magnetic fields are known as clean,economic,and effective tools to modify band and magnetic structures of materials.When coupled with catalytic processes such as the hydrogen evolution reaction(HER),they have the potential to control catalytic efficiency.Herein,we studied the magnetic response of a series of materials as HER catalysts,specifically ferromagnetic Co_(2)VGa,Co_(2)MnGa,and Ni,ferrimagnetic Mn_(2)CoGa,and paramagnetic Pt.
基金the National Key Research and Development Program of China(Grant number 2021YFA0910601)the National Natural Science Foundation of China(Grant numbers 32022044 and 32001027).
文摘Maltose is a natural α-(1,4)-linked disaccharide with wide applications in food industries and microbial fermentation. However,maltose has scarcely been used for in vitro biosynthesis, possibly because its phosphorylation by maltose phosphorylase (MP)yields β-glucose 1-phosphate (β-G1P) that cannot be utilized by α-phosphoglucomutase (α-PGM) commonly found in in vitrosynthetic enzymatic biosystems previously constructed by our group. Herein, we designed an in vitro synthetic enzymaticreaction module comprised of MP, β-phosphoglucomutase (β-PGM), and polyphosphate glucokinase (PPGK) for thestoichiometric conversion of each maltose molecule to two glucose 6-phosphate (G6P) molecules. Based on this syntheticmodule, we further constructed two in vitro synthetic biosystems to produce bioelectricity and fructose 1,6-diphosphate (FDP),respectively. The 14-enzyme biobattery achieved a Faraday efficiency of 96.4% and a maximal power density of 0.6mW/cm^(2),whereas the 5-enzyme in vitro FDP-producing biosystem yielded 187.0mM FDP from 50 g/L (139mM) maltose by adopting afed-batch substrate feeding strategy. Our study not only suggests new application scenarios for maltose but also provides novelstrategies for the high-efficient production of bioelectricity and value-added biochemicals.
基金supported by the Fund of Fujian Science&Technology Innovation Laboratory for Optoelectronic Information(2020ZZ114)the Key Research Program of Frontier Science CAS(QYZDY-SSW-SLH025)+1 种基金the National Natural Science Foundation of China(21731006 and 21871256)the Fund of Advanced Energy Science and Technology Guangdong Laboratory(DJLTN0200/DJLTN0240)。
文摘Trivalent lanthanide(Ln^(3+))-doped luminescent nanoparticles(NPs)have been extensively investigated as deep-tissue-penetration visual bioimaging agents owing to their exceptional upconversion and near-infrared(NIR)luminescence upon irradiation of NIR light.However,in most cases,the power density of irradiation used for in vivo biological imaging is much higher than that of the reported maximum permissible exposure(MPE)value of NIR light,which inevitably does great damage to the living organisms under study and thus impedes the plausible clinical applications.Herein,by using a facile syringe pump-aided shell epitaxial growth method,we construct for the first time a new class of Ln^(3+)-doped KMgF_(3):Yb/Er@KMgF_(3)core-shell NPs that can be activated by utilizing a 980-nm xenon lamp or diode laser with an ultralow excitation power density down to 0.08 mW cm^(−2),a value that is approximately 4 orders of magnitude lower than the MPE value set by the American National Standards Institute(ANSI)for safe bioimaging in vivo.By combining the comparative spectroscopic investigations with atomic-resolved spherical aberration corrected transmission electron microscopy(AC-TEM)characterization,we find that the reduced crystallographic defects are the primary cause underlying such an ultralow-power-excitable feature of the KMgF_(3):Yb/Er@KMgF_(3)core-shell NPs.And,by the same token,the resultant KMgF_(3):Yb/Er@KMgF_(3)core-shell NPs also exhibit an anomalous thermo-enhanced photoluminescence(PL)behavior coupled with an excellent photothermal stability that cannot occur in other Ln^(3+)-doped core-shell NPs.These findings described here unambiguously pave a new way to prepare high-quality Ln^(3+)-doped luminescent NPs with desirable ultralow-power-excitable capability and photothermal stability for future biomedical applications.
基金This work was financially supported by the European Research Council(ERC Advanced Grant No.742068 T'OPMAT')We also acknowledge funding by the DFG through SFB 1143(project ID.247310070)+1 种基金the Würzburg-Dresden Cluster of Excellence on Complexity and Topology in Quantum Matter ct.qmat(EXC2147,project ID.39085490)via DFG project HE 3543/35-1.JC Rao acknowledges the support of the Maryland NanoCenter and its AIM Lab.Some of our calculations are carried on the cluster of MPCDF,Max Planck Society.
文摘The difficulties in designing high-performance hydrogen evolution reaction(HER)catalysts lie in the manipulation of adsorption behaviors of transition metals(TMs).Topological chiral semimetals with super-long Fermi arc surface states provide an ideal platform for engineering the catalytic performance of TMs through the metal-support interaction.We found the adsorption trends of TMs can be modified significantly when deposited at the surface of the PdGa chiral crystal.The electron transfer from the TMs to the surface states of the PdGa reshapes the d band structure of TMs and weakens the hydrogen intermediate bonding.Especially,W/PdGa is expected to be a good HER catalyst with close to zero Gibbs free energy.Experimentally,we found a Pt-like exchange current density and tumover frequency when depositing W atoms at the PdGa nanostructures surface.The findings provide a way to develop high-efficient electrocatalysts by the interplay between topological surface states and metal-support interaction.
基金This work was financially supported by the ERC advanced grant No.(742068)“TOP-MAT”.Ch.F and S.N.G.acknowledge financial support from the Alexander von Humboldt FoundationT.S.acknowledges support from the Emergent Phenomena in Quantum Systems initiative of the Gordon and Betty Moore Foundation+1 种基金A.K.S.was funded by the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)—project number 314790414M.E.K.supported by The Netherlands Organization for Science NWO(graduate program 2013,No.022.005.006).
文摘Highly conductive topological semimetals with exotic electronic structures offer fertile ground for the investigation of the electrical and thermal transport behavior of quasiparticles.Here,we find that the layer-structured Dirac semimetal PtSn4 exhibits a largely suppressed thermal conductivity under a magnetic field.At low temperatures,a dramatic decrease in the thermal conductivity of PtSn4 by more than two orders of magnitude is obtained at 9 T.Moreover,PtSn_(4)shows both strong longitudinal and transverse thermoelectric responses under a magnetic field.Large power factor and Nernst power factor of approximately 80-100μW·cm^(-1)·K^(-2)are obtained around 15K in various magnetic fields.As a result,the thermoelectric figure of merit zT is strongly enhanced by more than 30 times,compared to that without a magnetic field.This work provides a paradigm for the decoupling of the electron and hole transport behavior of highly conductive topological semimetals and is helpful for developing topological semimetals for thermoelectric energy conversion.