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CS-LTP-Spinal: a cross-layer optimized rate-adaptive image transmission system for deep-space exploration

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Science China(Information Sciences) 2022年第1期65卷 218-233页

作者： Shaohua WU Dongqing LI jian jiao Qinyu ZHANG School of Electronics and Information Engineering Harbin Institute of Technology (Shenzhen)

Reliable and efficient image transmission is crucial for deep-space exploration. However, the extremely long distance and complex deep-space environment introduce severe design and implementation challenges. In this work, we propose a novel high-efficiency system, CS-LTP-Spinal, to address the challenges encountered in deep-space image transmission. CS-LTP-Spinal is designed to work over the Licklider transmission protocol(LTP) of the delay-tolerant network(DTN). By incorporating compressed sensing(CS)and the Spinal codes as the application and physical layer techniques, CS-LTP-Spinal can satisfy the constraints originating from resource asymmetry between the space vehicles and the ground station. To match the time-varying deep-space channels, two coarse-grained rate-adaptive transmission strategies are designed that employ different CS decompression mechanisms based on erasure-tolerant and error-tolerant decompression, respectively, to exploit the robustness of CS reconstruction to erasures and errors. Then, the rates of CS compression and Spinal coding are optimized over the application, transport, and physical layers. A semi-physical deep-space communication platform is built, and extensive simulations on the Mars-to-Earth scenario are conducted. The results demonstrate that the designed CS-LTP-Spinal system with cross-layer optimized rate-adaptive transmission strategies has significant performance advantages over its counterparts by achieving near-ideal image transmission efficiency.

关键词： deep-space image transmission CS-LTP-Spinal rate-adaptive cross-layer optimization semi-physical simulation

Joint channel estimation and beam selection NOMA system for satellite-based Internet of Things

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Science China(Information Sciences) 2022年第10期65卷 270-284页

作者： Zeqiong CHEN jian jiao Shaohua WU Qinyu ZHANG Communication Engineering Research Centre Harbin Institute of Technology (Shenzhen) Peng Cheng Laboratory

Multibeam low earth orbit(LEO) millimeter wave(mm Wave) band high throughput satellite(HTS) is regarded as a key component in the upcoming satellite-based Internet of Things(S-Io T). The multibeam LEO HTS with non-orthogonal multiple access(NOMA) can support global coverage and low latency broadband access over a wide geographical area in a cost-efficient manner. However, the performance is constrained by the channel state information and subsequent beam selection in multibeam LEO HTS.We design a joint channel estimation and beam selection NOMA system for S-Io T in this paper, including the pseudo random ergodic(PRE)-throughput maximum(TM) scheme for massive multiple access, and the asynchronous CSI-assisted(AIA)-TM scheme for high throughput services. Moreover, we propose the PREfairness guaranteed(FG) and AIA-FG schemes for achieving better fairness with slightly loss of throughput.Simulation results show that the PRE-TM and AIA-TM schemes can adaptively reduce the required channel measurements, while approaching the optimal system throughput performance of the exhaust searching(ES)scheme with a much lower computational complexity.

关键词： satellite-based Internet of Things non-orthogonal multiple access channel estimation system throughput fairness

Achieving ultra-broadband electromagnetic absorption of Ag regulated hollow Ag/CuO@CuS through balancing conduction loss and impedance matching

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Journal of Materials Science & Technology 2023年第13期144卷 81-92页

作者： Siyuan Zhang Jinlei Tao Rui Sun Shipeng Hu jian jiao Northwestern Polytechnical University Xi’an 710072China

Excellent impedance matching and high conduction loss are important factors for the preparation of high-performance electromagnetic wave(EMW)absorbing materials,but these two properties are of-ten contradictory.In this work,three absorbers with unique hollow structures,H-Ag/CuO@CuS,H-O-Ag/CuO@CuS,and H-P-Ag/CuO@CuS,are designed and synthesized by adopting hollow CuO@CuS with double shell as carrier and silver nitrate as the structural regulator.The more voids coming from hol-low structures,window-opened structures,and stacked pores improve the impedance matching of these absorbers,and the introduction of elemental Ag effectively regulates the conduction loss.Therefore,a balance between impedance matching and conduction loss is achieved to improve the reflection loss(RL)value and broadens the absorbing band of the absorbers.In comparison to H-Ag/CuO@CuS and H-O-Ag/CuO@CuS(hollow structure with open window)in which elemental Ag is uniformly dispersed in the CuO layer,H-P-Ag/CuO@CuS exhibits more excellent EMW absorption performance due to more voids and an optimized conductive network arising from Ag/CuO pieces distributed between the hol-low Ag/CuO@CuS particles and Ag distributed in the CuS layer.When the thickness is 2.3 mm,H-P-Ag/CuO@CuS provides an ultra-wide electromagnetic absorption band of 8.56 GHz(9.44-18 GHz),in which the RL<-10 dB and the minimum reflection loss of-41 dB.

关键词： Elemental sliver Impedance matching Conduction loss Electromagnetic wave absorption

Loss of SHROOM3 affects neuroepithelial cell shape through regulating cytoskeleton proteins in cynomolgus monkey organoids

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Zoological Research 2024年第2期45卷 233-241页

作者： Peng Li Ting Zhang Ruo Wu Jun-Yu Zhang Yan Zhuo Shan-Gang Li jiao-jian Wang Wen-Ting Guo Zheng-Bo Wang Yong-Chang Chen State Key Laboratory of Primate Biomedical Research Institute of Primate Translational MedicineKunming University of Science and TechnologyKunmingYunnan 650500China Yunnan Key Laboratory of Primate Biomedical Research KunmingYunnan 650500China

Neural tube defects(NTDs)are severe congenital neurodevelopmental disorders arising from incomplete neural tube closure.Although folate supplementation has been shown to mitigate the incidence of NTDs,some cases,often attributable to genetic factors,remain unpreventable.The SHROOM3 gene has been implicated in NTD cases that are unresponsive to folate supplementation;at present,however,the underlying mechanism remains unclear.Neural tube morphogenesis is a complex process involving the folding of the planar epithelium of the neural plate.To determine the role of SHROOM3 in early developmental morphogenesis,we established a neuroepithelial organoid culture system derived from cynomolgus monkeys to closely mimic the in vivo neural plate phase.Loss of SHROOM3 resulted in shorter neuroepithelial cells and smaller nuclei.These morphological changes were attributed to the insufficient recruitment of cytoskeletal proteins,namely fibrous actin(F-actin),myosin II,and phospho-myosin light chain(PMLC),to the apical side of the neuroepithelial cells.Notably,these defects were not rescued by folate supplementation.RNA sequencing revealed that differentially expressed genes were enriched in biological processes associated with cellular and organ morphogenesis.In summary,we established an authentic in vitro system to study NTDs and identified a novel mechanism for NTDs that are unresponsive to folate supplementation.

关键词： Neural tube defects SHROOM3 Neuroepithelial Organoids Cynomolgus monkey

Response of erosion reduction effect of typical soil and water conservation measures in cropland to rainfall and slope gradient changes and their applicable range in the Chinese Mollisols Region,Northeast China

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International Soil and Water Conservation Research 2023年第2期11卷 251-262页

作者： Qin Zhang Wei Qin Wenhong Cao jian jiao Zhe Yin Haichao Xu State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBejing100048PR China Research Center on Soil and Water Conservation of the Ministry of Water Resources Beijing100048PR China

Mollisols are rich in organic matter,which makes them suitable for cultivation and for enhancing global food security.Mollisols are experiencing severe soil erosion due to overfarming and a lack of mainte-nance.Thus,suitable soil and water conservation measures(SWCMs)are needed to protect Mollisols.However,how SWCMs respond to changes in slope gradient and rainfall and their effective application area remain ambiguous.Using a long-term field observation dataset,meta-analysis,and statistical test methods,we reveal the typical erosion reduction effect of SWCMs and their responses to changes in slope gradient and rainfall.Next,we calculated a coupling factor,P.S,by slope gradient and rainfall in flood season to determine the effective SWCMs application threshold.Compared with bare land,no-tillage(NT),contour ridge tillage(CT),ridge hedgerows(RH),and terraced fields(TF)had an average erosion reduction coefficient of 91.5%.There was a significant exponential increase in the correlation between P.S and the soil erosion amount in plots with typical measures.According to this correlation and soil loss tolerance(200 t/km^(2)),the upper limits of PS(NT:564 mm;CT:885 mm;RH:1135 mm)were determined and utilized to determine the effective application areas(NT:311.40103 km^(2);CT:320.86103 km^(2);RH:323.72103 km^(2))at the plot scale.In wet years,the applicable area of SWCMs declined toward the low-elevation foothills and flat terrain.All the results are applicable when slope length within 20 m.These results provide a basis for the precise allocation of SWCMs in Mollisols area and promote the scientific utilization of Mollisols resources.

关键词： Mollisols region Watererosion in cropland Soil and water conservationmeasures Erosionreductioncoefficient Effective range

Adsorption of Co(Ⅱ)from aqueous solutions by water treatment residuals

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Journal of Environmental Sciences 2017年第2期29卷 232-239页

作者： jian jiao Jinbo Zhao Yuansheng Pei The Key Laboratory of Water and Sediment Sciences Ministry of EducationSchool of EnvironmentBeijing Normal UniuersityBeijing 100875China

A study on the removal of Co（Ⅱ） from aqueous solutions by water treatment residuals（WTR） was conducted in batch conditions. The sorption process of Co（Ⅱ） followed pseudosecondorder kinetics, with 30 hr required to reach equilibrium. Using the Langmuir adsorption isotherm model, a relatively high maximum sorption capacity of 17.31 mg/g Co（Ⅱ） was determined. The adsorption of Co（Ⅱ） was dependent on pH values and was affected by the ionic strength. Results show that Co（Ⅱ） adsorption was a spontaneous endothermic process and was favorable at high temperature. Most of the adsorbed Co（Ⅱ） stayed on the WTR permanently, whereas only small amounts of adsorbed Co（Ⅱ） were desorbed. The shifting of peaks in FT-IR spectra indicated that Co（Ⅱ） interacted with the WTR surface through strong covalent bond formation with Fe（Al）–O functional groups. It was concluded that WTR can be a suitable material from which to develop an efficient adsorbent for the removal of Co（Ⅱ） from wastewater.

关键词： Water treatment residuals Co（II） Adsorption Desorption FT-IR

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Photothermal therapy with regulated Nrf2/NF-κB signaling pathway for treating bacteria-induced periodontitis

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Bioactive Materials 2022年第3期7卷 428-445页

作者： Yujuan Tian Ying Li Jialin Liu Yi Lin jian jiao Bo Chen Wanmeng Wang Shuilin Wu Changyi Li School of Dentistry Stomatological HospitalTianjin Medical UniversityTianjin300070People’s Republic of China School of Materials Science&Engineering Key Laboratory of Advanced Ceramics and Machining Technology by the Ministry of Education of ChinaTianjin UniversityTianjin300072People’s Republic of China

Periodontitis is an inflammatory disease initiated by bacterial infection,developed by excessive immune response,and aggravated by high level of reactive oxygen species(ROS).Hence,herein,a versatile metal-organic framework(MOF)-based nanoplatform is prepared using mesoporous Prussian blue(MPB)nanoparticles to load BA,denoted as MPB-BA.The established MPB-BA nanoplatform serves as a shelter and reservoir for vulnerable immunomodulatory drug BA,which possesses antioxidant,anti-inflammatory and anti-bacterial effects.Thus,MPB-BA can exert its antioxidant,anti-inflammatory functions through scavenging intracellular ROS to switch macrophages from M1 to M2 phenotype so as to relieve inflammation.The underlying molecular mechanism lies in the upregulation of phosphorylated nuclear factor erythroid 2-related factor 2(Nrf2)to scavenge ROS and subsequently inhibit the nuclear factor kappa-B(NF-κB)signal pathway.Moreover,MPB-BA also exhibited efficient photothermal antibacterial activity against periodontal pathogens under near-infrared(NIR)light irradiation.In vivo RNA sequencing results revealed the high involvement of both antioxidant and anti-inflammatory pathways after MPB-BA application.Meanwhile,micro-CT and immunohistochemical staining of p-Nrf2 and p-P65 further confirmed the superior therapeutic effects of MPB-BA than minocycline hydrochloride.This work may provide an insight into the treatment of periodontitis by regulating Nrf2/NF-κB signaling pathway through photothermal bioplatform-assisted immunotherapy.

关键词： Periodontitis Prussian blue Photothermal therapy Nrf2/NF-κB signaling pathway Bacterial infection

Comparison of human nasal epithelial cells grown as explant outgrowth cultures or dissociated tissue cultures in vitro

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Frontiers of Medicine 2013年第4期7卷 486-491页

作者： jian jiao Na Meng Hong Wang Luo Zhang Department of Otolaryngology Head and Neck SurgeryBeijing Tongren HospitalCapital Medical UniversityBeijing 100005ChinaKey Laboratory of OtolaryngologyHead and Neck Surgery(Ministry of Education)Beijing Institute of OtolaryngologyBeijing 100005China

The purpose of this study was to compare cell growth characteristics,ciliated cell differentiation,and function of human nasal epithelial cells established as explant outgrowth cultures or dissociated tissue cultures.Human nasal mucosa of the uncinate process was obtained by endoscopy and epithelial cell cultures were established by explant outgrowth or dissociated tissue culture methods.Epithelial cell growth characteristics were observed by inverted phase contrast microscopy.Ciliated cell differentiation was detected byβ-tubulin IV and ZO-1 immunocytochemistry.Basal and ATP-stimulated ciliary beat frequency(CBF)was measured using a high-speed digital microscopic imaging system.Both the explant and dissociated tissue cultures established as monolayers with tight junctions and differentiated cell composition,with both types of cultures comprising ciliated and non-ciliated epithelial cells.Fibroblasts were also frequently found in explant cultures but rarely seen in dissociated tissue cultures.In both culture systems,the highest ciliated cell density appeared at 7th–10th culture day and declined with time,with the lifespan of ciliated cells ranging from 14 to 21 days.Overall,10%of the cells in explant cultures and 20%of the cells in the dissociated tissue cultures were ciliated.These two cultures demonstrated similar ciliary beat frequency values at baseline(7.78±1.99 Hz and 7.91±2.52 Hz,respectively)and reacted equivalently following stimulation with 100μM ATP.The results of this study indicate that both the explant outgrowth and dissociated tissue culture techniques are suitable for growing well-differentiated nasal ciliated and non-ciliated cells,which have growth characteristics and ciliary activity similar to those of nasal epithelial cells in vivo.

关键词： ciliated cells ciliary beat frequency dissociated tissue culture explant culture nasal epithelial cells

Exogenous melatonin alleviated growth inhibition and oxidative stress induced by drought stress in apple rootstock

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BIOCELL 2022年第7期46卷 1763-1770页

作者： MEIGE WANG JUAN GONG CHUNHUI SONG ZHENGYANG WANG SHANGWEI SONG jian jiao MIAOMIAO WANG XIANBO ZHANG TUANHUI BAI College of Horticulture Henan Agricultural UniversityZhengzhou450002China

Drought stress is one of the major environmental obstacles that limit the production and development of apples(Malus domestica Borkh.).The role of melatonin is well known in the protection of plants under environmental stresses.In this study,we investigated the effect of melatonin on apple rootstock M.hupehensis Rehd under drought stress.The results showed that drought inhibited the growth of M.hupehensis and dramatically reduced root surface area,root volume,the number of tips and forks,and root diameter.Drought-induced growth inhibition was significantly decreased by adding *** photosynthetic rate(Pn),intercellular CO_(2)concentration(Ci),stomatal conductance(Gs),transpiration rate(Tr),were markedly reduced under drought stress.However,the application of melatonin could mitigate the damage to the photosynthetic apparatus and increase the quantum yield of PSII photochemistry.Additionally,generation of hydrogen peroxide(H_(2)O_(2))and superoxide radicals(O_(2)^(•–))sharply increased in apple leaves after 4 days under drought stress,and the accumulation of electrolyte leakage(EL)represented oxidative stress,while by applying melatonin under drought stress,the generation of O_(2)^(•–)and H_(2)O_(2)were significantly reduced and protected the membrane from drought damages.These results suggest that the adverse effects of drought can be minimized by applying melatonin to apples.

关键词： Apple Chlorophyll fluorescence Drought Melatonin Photosynthesis