Objective:To explore the anti-aging effects of chlorogenic acid(CGA)and the underlying mechanisms based on a Caenorhabditis elegans(C.elegans)model.Methods:The anti-agingactivityofCGAwasstudied basedon thebodylength,e...Objective:To explore the anti-aging effects of chlorogenic acid(CGA)and the underlying mechanisms based on a Caenorhabditis elegans(C.elegans)model.Methods:The anti-agingactivityofCGAwasstudied basedon thebodylength,exercisebehavior,lipofuscin content,antioxidative stress ability,swallowing frequency,body-bending frequency,and head-swinging ability of C.elegans.Through DAF-16 nuclear translocation and SOD-3-GFP fluorescence experiments,the effects of CGA on ROS levels,antioxidant enzyme activities,MDA content,mutant-strain lifespan,and anti-aging molecular signaling pathways were explored,as well as the underlying mechanisms.Results:CGA improved multiple indices of the nematode:body length was increased(all P<0.001),head-swing frequency and body-bending frequency were increased(all P<0.05),nematode longevity was prolonged(P=0.0021),lipofuscin deposition in nematodes was slowed down(all P<0.001),the chemotaxis index was improved(P=0.0012),ROS levels were reduced(all P<.001),and SOD activity and MDA content were reduced(SOD:P=0.0017 between the low-concentration group and the control group,P<.001 between the high-concentration and medium-concentration groups and the control group;MDA:P=0.0135 between the low-concentration group and the control group,and P<0.001 between the high-concentration and medium-concentration groups and the control group).In addition,CGA also activated the DAF-16 transcription factor,promoted DAF-16 nuclear translocation under oxidative stress conditions(both P<0.001 between the high-concentration and medium-concentration groups and the control group),and increased SOD-3 gene expression in nematodes(all P<0.001).Conclusion:CGA plays an anti-aging role in C.elegans.The underlying mechanisms include activation of the insulin/IGF-1 signaling pathway and enhancement of DAF-16 activity.This study lays a foundation for further research into the anti-aging effects of CGA.展开更多
Flavonoids are secondary metabolites in plants and possess extensive pharmacological activities.Flavonoids have remarkable effect in prevent anti-tumor and cancer,but flavonoids can't be synthesized directly in th...Flavonoids are secondary metabolites in plants and possess extensive pharmacological activities.Flavonoids have remarkable effect in prevent anti-tumor and cancer,but flavonoids can't be synthesized directly in the body.According to the different properties and structures of flavonoids in Traditional Chinese medicines,different extraction methods should be selected.Besides,flavonoids have good anti-aging effects.Based on three theories of modern aging,the anti-aging effect of flavonoids was discussed.It is expected to provide a beneficial reference for further development and utilization of natural flavonoid resources.展开更多
To evaluate the potential anti-aging ability of Eucommia ulmoides,four characteristic components(chlorogenic acid,geniposidic acid,aucubin,quercetin)were selected to assess their effects on H_(2)O_(2)-induced oxidativ...To evaluate the potential anti-aging ability of Eucommia ulmoides,four characteristic components(chlorogenic acid,geniposidic acid,aucubin,quercetin)were selected to assess their effects on H_(2)O_(2)-induced oxidative damage model of human umbilical vein endothelial cell(HUVEC).Oxidative damage indexes,inflammatory factors,cell cycle,cell apoptosis,cell senescence,and their related proteins were analyzed by methyl thiazolyl tetrazolium(MTT)assay,enzyme-linked immunosorbent assay(ELISA),propidium iodide(PI)staining,annexin V-FITC/PI double staining,SAβ-galactosidase staining,and western blotting(WB).The results showed that H_(2)O_(2)-induced cell growth inhibition rate decreased as supplementation with characteristic components when compared to H_(2)O_(2) group.Meanwhile,the contents of antioxidant indexes(reactive oxygen species,lactate dehydrogenase,molondialdehyde,superoxide dismutase,glutathione),inflammatory factors(nuclear factor kappa-B,intercellular cell adhesion molecule-1,vascular cell adhesion protein 1),and functional factors(NO,Endothelin-1)in characteristic components treated groups improved if comparison with H_(2)O_(2) group,suggesting the characteristic components of E.ulmoides could alleviate H_(2)O_(2)-induced oxidative damage.Moreover,cell cycle,cell apoptosis,cell senescence,and their related proteins under characteristic components treatment exhibited a better effect than under H_(2)O_(2) treatment,implying the characteristic components could participate in anti-aging via multiple pathways.These results manifested that the characteristic components of E.ulmoides posses the capacity of anti-aging,which provided a basis for investigating the anti-aging ability of E.ulmoides itself.展开更多
Background: The time-related decline in regenerative capacity and organ homeostasis is a major feature of aging. Rehmannia glutinosa and Astragalus membranaceus have been used as traditional Chinese herbal medicines f...Background: The time-related decline in regenerative capacity and organ homeostasis is a major feature of aging. Rehmannia glutinosa and Astragalus membranaceus have been used as traditional Chinese herbal medicines for enhanced immunity and prolonged life. However, the mechanism by which this herbal medicine slows aging is unknown. In this study, we investigated the mechanism of the herbal anti-aging effect.Methods: Mice were fed diets supplemented with R. glutinosa or A. membranaceus for 10 months; the control group was fed a standard diet. The phenotypes were evaluated using a grading score system and survival analysis. The percentages of the senescence phenotypes of hematopoietic stem cells(HSCs) were determined by fluorescence-activated cell sorting analysis. The function and the mechanism of HSCs were analyzed by clonogenic assay and the real-time polymerase chain reaction.Results: The anti-aging effect of R. glutinosa is due to the enhanced function of HSCs. Mice fed with R. glutinosa displayed characteristics of a slowed aging process,including decreased senescence and increased rate of survival. Flow cytometry analysis showed decreased numbers of Lin–Sca1^+c-kit–(LSK) cells, long-term HSCs(LT-HSCs) and short-term HSCs(ST-HSCs) in the R. glutinosa group. In vitro, clonogenic assays showed increased self-renewal ability of LT-HSCs from the R. glutinosa group as well as maintaining LSK quiescence through upregulated p18 expression. The R. glutinosa group also showed decreased reactive oxygen species levels and the percentage of β-gal^+ cells through downregulation of the cellular senescence-associated protein p53 and p16.Conclusion: Rehmannia glutinosa exerts anti-aging effects by maintaining the quiescence and decreasing the senescence of HSCs.展开更多
OBJECTIVE Behavior research and urinary metabolomics method were applied to evaluate the anti-aging effects of Scutellaria baicalensis Georgi extract(SBG)in D-galactose-induced rats.METHODS Fifty rats were randomly di...OBJECTIVE Behavior research and urinary metabolomics method were applied to evaluate the anti-aging effects of Scutellaria baicalensis Georgi extract(SBG)in D-galactose-induced rats.METHODS Fifty rats were randomly divided into five groups(n=10in each group).Group 1served as vehicle control with injection of saline(vehicle control group),and the other groups of rats received daily subcutaneously injected with D-galactose(aged model group)at dose of 100mg·kg-1 for ten weeks,respectively.At the same time,rats in groups 3-5were intragastrically administered SBG 〔extracted twice with 60%(V/V)ethanol〕at doses of 50,100 and 200mg·kg-1 for ten weeks,and the rats of groups 1 and 2 were administrated an equal volume of the vehicle.At the tenth week,the learning and memory abilities were examined by Morris water maze.The urine was collected using metabolic cages and analyzed by high-resolution 1HNMR spectroscopy combined with multivariate statistical analyses.Principal component analysis(PCA)was utilized to classify and reveal the differences between the model group and control group.Then,the concentration of these differences was analyzed with t-test to determine whether SBG was possible to influence the metabolic pattern induced by D-galactose.RESULTS Compared with the vehicle control group,the D-galactose-treated aged model group markedly spent longer time(P<0.05)in finding the platform on days 3-5 in the spatial learning acquisition training of Morris water maze test.However,the escape latency was significantly reduced(P<0.05)by long-term administration of SBG(50,100 and 200mg·kg-1)compared with the D-galactose-treated aged model group on days 3-5.In the probe test,the D-galactose-treated aged model group made fewer(P<0.05)platform crossings and distance travelled in target quadrant(P<0.05)than the vehicle control group,and the SBG at doses of 50,100 and 200mg·kg-1 treatments groups could significantly increase(P<0.05)the number of times of crossing over the platform site.The SBG at doses of100 and 200mg·kg-1 treatments groups could significantly increase(P<0.05)the distance travelled in target quadrant compared with the D-galactose-treated aged model group.In addition,the significant difference in metabolic profiling was observed from model group compared with drug-dose group by using PCA,indicating the recovery effect of SBG on D-galactose induced aging rats.Some significantly changed metabolites like glycine,glucose and hexadecanoic acid have been identified.These biochemical changes are related to the the disturbance in aimno acid metabolism,energy metabolism and glycometabolism,which are helpful to further understanding the D-galactose induced aging rats and the therapeutic mechanism of SBG.CONCLUSION These results demonstrate that SBG extract has protective effect on the D-galactose-induced aging in rats.展开更多
Boron is an ambitious fuel in energetic materials since its high heat release values,but its application is prohibited by low combustion efficiency and oxidization during storage.The polydopamine(PDA)was introduced in...Boron is an ambitious fuel in energetic materials since its high heat release values,but its application is prohibited by low combustion efficiency and oxidization during storage.The polydopamine(PDA)was introduced into boron particles,investigating the impact of PDA content on the energetic behavior of boron.The results indicated that the PDA coating formed a fishing net structure on the surface of boron particles.The heat release results showed that the combustion calorific value of B@PDA was higher than that of the raw boron.Specifically,the actual combustion heat of boron powder in B@10%PDA increased by 38.08%.Meanwhile,the DSC peak temperature decreased by 100.65℃under similar oxidation rate compared to raw boron.Simultaneously,the B@PDA@AP and B@AP composites were prepared,and their combustion properties were evaluated.It was demonstrated that B@10%PDA@AP exhibited superior performance in terms of peak pressure and burning time,respectively.The peak pressure is 12.43 kPa more than B@AP and burning time is 2.22 times higher than B@AP.Therefore,the coating of PDA effectively inhibits the oxidization of boron during storage and enhances the energetic behavior of boron and corresponding composites.展开更多
The fruits of Paulownia catalpifolia Gong Tong are used as a Chinese folk herbal medicine for the treatment of enteritis, tonsillitis, bronchitis, and dysentery, etc. Our previous study has identified new C-geranylate...The fruits of Paulownia catalpifolia Gong Tong are used as a Chinese folk herbal medicine for the treatment of enteritis, tonsillitis, bronchitis, and dysentery, etc. Our previous study has identified new C-geranylated flavanones with obvious anti-proliferative effects in lung cancer A549 cells. In the present study, a new C-geranylated flavone, paucatalinone C(1) and five known C-geranylated flavanones(2-6) were isolated. In addition, a total of 34 C-geranylated flavonoids were detected by HPLC-DAD-ESI-MS/MS coupling techniques from the CH_2Cl_2 extract of P. catalpifolia. Futhermore, anti-aging effects of isolated compounds were evaluated in vitro with premature senescent 2BS cells induced by H_2O_2. Phytochemical results indicated that P. catalpifolia was a natural resource of abundant C-geranylated flavonoids. Diplacone(3) and paucatalinone A(5) were the potent anti-aging agents in the premature senescent 2BS cells induced by H_2O_2 and the C-geranyl substituent may be an important factor because of its lipophilic character.展开更多
The purpose of this study was to explore the potential of the development and application of Paecilomyces hepiali,a fungus with edible and medicinal value,as a foodborne antioxidant and anti-aging agent.Its n-butanol ...The purpose of this study was to explore the potential of the development and application of Paecilomyces hepiali,a fungus with edible and medicinal value,as a foodborne antioxidant and anti-aging agent.Its n-butanol extract(PHE)from rice cultures was selected for anti-aging experiment because of significant free radical scavenging activity in vitro.In vivo,PHE could significantly prolong the mean lifespan,50%survival days,and the maximum lifespan of Drosophila on a high-fat diet.It is amazing that the mean lifespan increased from 19.1 days to 32.9 days,50%survival days increased from 15.7 days to 34.3 days,and the maximum lifespan extended from 44.7 days to 52.7 days,when the high-fat female Drosophila model was fed with 10μg/mL PHE.Further research showed that PHE reduced the accumulation of peroxide products and increased the activity of antioxidant enzymes.Then,through antioxidant activity tracking,dimerumic acid(compound 1,the IC_(50) value of 3.4μg/mL on DPPH free radicals scavenging activity),4,5-dihydroxy-3-methoxypentanoic acid(compound 2,new compound),and thymidine(compound 3)were isolated from PHE.It is worth mentioning that dimerumic acid,the major antioxidant compound of PHE(content up to 3%),was discovered in P.hepiali for the first time.It was concluded that PHE showed excellent anti-aging activity at a very low concentration on fat diet-induced high fat Drosophila melanogaster,and dimerumic acid may be its main material basis.These results indicated that PHE had the potential to be developed as antioxidant and anti-aging agent in the healthcare industry.展开更多
Sulfonylureas are widely used oral anti-diabetic drugs.However,its long-term usage effects on patients’lifespan remain controversial,with no reports of influence on animal longevity.Hence,the anti-aging effects of ch...Sulfonylureas are widely used oral anti-diabetic drugs.However,its long-term usage effects on patients’lifespan remain controversial,with no reports of influence on animal longevity.Hence,the anti-aging effects of chlorpropamide along with glimepiride,glibenclamide,and tolbutamide were studied with special emphasis on the interaction of chlorpropamide with mitochondrial ATP-sensitive K+(mito K-ATP)channels and mitochondrial complex II.Chlorpropamide delayed aging in Caenorhabditis elegans,human lung fibroblast MRC-5 cells and reduced doxorubicin-induced senescence in both MRC-5 cells and mice.In addition,the mitochondrial membrane potential and ATP levels were significantly increased in chlorpropamide-treated worms,which is consistent with the function of its reported targets,mito K-ATP channels.Increased levels of mitochondrial reactive oxygen species(mt ROS)were observed in chlorpropamide-treated worms.Moreover,the lifespan extension by chlorpropamide required complex II and increased mt ROS levels,indicating that chlorpropamide acts on complex II directly or indirectly via mito K-ATP to increase the production of mt ROS as a pro-longevity signal.This study provides mechanistic insight into the anti-aging effects of sulfonylureas in C.elegans.展开更多
As post-WWII baby boomer approaching age 80, Anti-Aging Regenerative Cosmetology (AARC) has been developed and patented for beautifying and strengthening the human body using live cells;to enhance the appearance and f...As post-WWII baby boomer approaching age 80, Anti-Aging Regenerative Cosmetology (AARC) has been developed and patented for beautifying and strengthening the human body using live cells;to enhance the appearance and function of various bodily parts to provide health and aestheticism of human being throughout life. It is a combined cosmetic and preventive medicine to intervene with and to correct the undesirable phenotypic expression of aging. The intrinsic properties of myoblasts and foreskin fibroblasts in development and regeneration are harnessed to formulate a genetic cell therapy program which is safe and efficacious as previously been tested in FDA Phase III clinical trials. Myoblasts are selected for strength development and foreskin fibroblasts for tenacity and smooth-to-the-touch. Both cell types are highly mitotic and non-carcinogenic. In additional to providing large quantities of nuclei as regenerative gene medicine, and of mitochondria as energy generators, myoblasts secret tumor necrosis factor alpha (TNF-α) for skin whitening and melanoma prevention. Myoblasts, because of their small size, spindle shape, and resilience, grow readily on collagen and laminin within wrinkles of skin surfaces, thus enhancing the color, luster, and texture of the skin “plated” with them. Alternatively, they can be injected subcutaneously as cell filler to reduce wrinkles. Intramuscular injection of myoblasts can augment the size, shape, consistency, tone, and strength of muscle groups, improving the lines, contours, and vitality to sculpt a youthful appearance. By improving cell genetics and organ functions, the program holds promise to sustain the human subject in good health and appearance, with a good quality of life and life prolongation.展开更多
Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinat...Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinations is more significant than a specific food component.This study investigated the lipid-lowering effect of highland barley polyphenols via lipase assay in vitro and HepG2 cells induced by oleic acid(OA).Five indexes,triglyceride(TG),total cholesterol(T-CHO),low density lipoprotein-cholesterol(LDL-C),aspartate aminotransferase(AST),and alanine aminotransferase(ALT),were used to evaluate the lipidlowering effect of highland barley extract.We also preliminary studied the lipid-lowering mechanism by Realtime fluorescent quantitative polymerase chain reaction(q PCR).The results indicated that highland barley extract contains many components with lipid-lowering effects,such as hyperoside and scoparone.In vitro,the lipase assay showed an 18.4%lipase inhibition rate when the additive contents of highland barley extract were 100μg/m L.The intracellular lipid-lowering effect of highland barley extract was examined using 0.25 mmol/L OA-induced HepG2 cells.The results showed that intracellular TG,LDL-C,and T-CHO content decreased by 34.4%,51.2%,and 18.4%,respectively.ALT and AST decreased by 51.6%and 20.7%compared with the untreated hyperlipidemic HepG2 cells.q PCR results showed that highland barley polyphenols could up-regulation the expression of lipid metabolism-related genes such as PPARγand Fabp4.展开更多
Extreme climate has increasingly led to negative impacts on forest ecosystems globally,especially in semiarid areas where forest ecosystems are more vulnerable.However,it is poorly understood how tree growth is affect...Extreme climate has increasingly led to negative impacts on forest ecosystems globally,especially in semiarid areas where forest ecosystems are more vulnerable.However,it is poorly understood how tree growth is affected by different drought events.In 2006–2009,the larch plantations in the semiarid areas of Northwest China were negatively affected by four consecutive dry years,which was a very rare phenomenon that may occur frequently under future climate warming.In this study,we analyzed the effect of these consecutive dry years on tree growth based on the data of the tree rings in the dominant layer of the forest canopy on a larch plantation.We found that the tree-ring width index(RWI)in dry years was lower than that in normal years,and it experienced a rapidly decreasing trend from 2006 to 2009(slope=-0.139 year^(-1),r=-0.94)due to water supply deficits in those dry years.Drought induced legacy effects of tree growth reduction,and consecutive dry years corresponded with greater growth reductions and legacy effects.Growth reductions and legacy effects were significantly stronger in the third and fourth consecutive dry years than that of single dry year(p<0.05),which might have been due to the cumulative stress caused by consecutive dry years.Our results showed that larch trees experienced greater tree growth reduction due to consecutive dry years and their legacy effect,and the trees had lower recovery rates after consecutive dry years.Our results highlight that consecutive dry years pose a new threat to plantations under climate warming,and thus,the effect of climate extremes on tree growth should be considered in growth models in semiarid areas.展开更多
240 nm AlGaN-based micro-LEDs with different sizes are designed and fabricated.Then,the external quantum efficiency(EQE)and light extraction efficiency(LEE)are systematically investigated by comparing size and edge ef...240 nm AlGaN-based micro-LEDs with different sizes are designed and fabricated.Then,the external quantum efficiency(EQE)and light extraction efficiency(LEE)are systematically investigated by comparing size and edge effects.Here,it is revealed that the peak optical output power increases by 81.83%with the size shrinking from 50.0 to 25.0μm.Thereinto,the LEE increases by 26.21%and the LEE enhancement mainly comes from the sidewall light extraction.Most notably,transversemagnetic(TM)mode light intensifies faster as the size shrinks due to the tilted mesa side-wall and Al reflector design.However,when it turns to 12.5μm sized micro-LEDs,the output power is lower than 25.0μm sized ones.The underlying mechanism is that even though protected by SiO2 passivation,the edge effect which leads to current leakage and Shockley-Read-Hall(SRH)recombination deteriorates rapidly with the size further shrinking.Moreover,the ratio of the p-contact area to mesa area is much lower,which deteriorates the p-type current spreading at the mesa edge.These findings show a role of thumb for the design of high efficiency micro-LEDs with wavelength below 250 nm,which will pave the way for wide applications of deep ultraviolet(DUV)micro-LEDs.展开更多
Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban...Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban forests and improvement of function.To clarify the effect of two forest types with different urbanization intensities,we determined differences in vegetation composition and diversity,structural traits,and carbon stocks of 152 plots(20 m×20 m)in urban park forests in Changchun,which had the largest green quantity and carbon density effectiveness.We found that 1.1-fold thicker and healthier trees,and 1.6-to 2.0-fold higher,healthier,denser,and more various shrubs but with sparser trees and herbs occurred in the central urban forests(p<0.05)than in the outer forests.The conifer forests exhibited 30–70%obviously higher tree aboveground carbon sequestration(including stem and leaf)and 20%bigger trees,especially in the outer forests(p<0.05).In contrast,1.1-to 1.5-fold higher branch stocks,healthier and more diverse trees were found in broadleaved forests of both the inner and outer forests(p<0.05).Plant size and dominant species had similarly important roles in carbon stock improvement,especially big-sized woody plants and Pinus tabuliformis.In addition,a higher number of deciduous or needle species positively affected the broadleaved forest of the central urban area and conifer forest of the outer urban area,respectively.These findings can be used to guide precise management and accelerate the improvement of urban carbon function in Northeast China in the future.展开更多
This paper realizes the full-domain collaborative deployment of multiple interference sources of the global satellite navigation system(GNSS)and evaluates the deployment effect to enhance the ability to disturb the at...This paper realizes the full-domain collaborative deployment of multiple interference sources of the global satellite navigation system(GNSS)and evaluates the deployment effect to enhance the ability to disturb the attacker and the capability to defend the GNSS during navigation countermeasures.Key evaluation indicators for the jamming effect of GNSS suppressive and deceptive jamming sources are first created,their evaluation models are built,and their detection procedures are sorted out,as the basis for determining the deployment principles.The principles for collaboratively deploying multi-jamming sources are developed to obtain the deployment structures(including the required number,structures in demand,and corresponding positions)of three single interference sources required by collaboratively deploying.Accordingly,simulation and hardware-in-loop testing results are presented to determine a rational configuration of the collaborative deployment of multi-jamming sources in the set situation and further realize the full-domain deployment of an interference network from ground,air to space.Varied evaluation indices for the deployment effect are finally developed to evaluate the deployment effect of the proposed configuration and further verify its reliability and rationality.展开更多
Sickle cell disease (SCD) is a prevalent condition, particularly in the countries of sub-Saharan Africa, where the presence of specific genes associated with Malaria contributes to its high prevalence. Patients with s...Sickle cell disease (SCD) is a prevalent condition, particularly in the countries of sub-Saharan Africa, where the presence of specific genes associated with Malaria contributes to its high prevalence. Patients with sickle cell disease frequently experience painful episodes necessitating hospitalization, and their hemoglobin levels are typically lower than those of the general population. There are different treatment options available to manage complications, such as transfusing blood, hydroxyurea, and strong anti-pains. However, with all these treatments, patients still commonly experience pain crises and suffer from organ damage. Hydroxyurea, the sole approved medication for sickle cell anemia in developed and developing countries, is widely used in children despite being primarily indicated for adults. Multiple studies have demonstrated the efficacy of hydroxyurea in inducing HbF production in young children with SCD. Elevated HbF levels have been associated with improved clinical outcomes, including a reduction in vaso-occlusive crises, acute chest syndrome, and the need for blood transfusions. Furthermore, increased HbF levels have been shown to ameliorate disease-related organ damage, such as pulmonary hypertension and sickle cell retinopathy. The response to hydroxyurea treatment in young children with SCD is variable. Some patients achieve substantial increases in HbF levels and experience significant clinical benefits, while others may have a more modest response. Factors influencing the response include baseline HbF levels, genetic modifiers, treatment adherence, and dose optimization. Safety is a crucial consideration when using hydroxyurea in young children. Studies have shown that hydroxyurea is generally well-tolerated, with the most common adverse effects being myelosuppression, gastrointestinal symptoms, and dermatological manifestations. However,long-term effects and potential risks, such as renal dysfunction and reproductive impacts, require further investigation. The effectiveness of hydroxyurea in young children with SCD has been demonstrated in various clinical trials and observational studies. These studies have shown a significant reduction in disease-related complications and improved quality of life. However, optimal dosing, treatment duration, and long-term outcomes are still areas of ongoing research. This review focuses on recent studies investigating the benefits, effectiveness, responses, and safety of hydroxyurea in pediatric individuals diagnosed with sickle cell disease.展开更多
Hybrid skin-topological effect(HSTE)in non-Hermitian systems exhibits both the skin effect and topological protection,offering a novel mechanism for localization of topological edge states(TESs)in electrons,circuits,a...Hybrid skin-topological effect(HSTE)in non-Hermitian systems exhibits both the skin effect and topological protection,offering a novel mechanism for localization of topological edge states(TESs)in electrons,circuits,and photons.However,it remains unclear whether the HSTE can be realized in quasicrystals.展开更多
To investigate the mechanism of rockburst prevention by spraying water onto the surrounding rocks,15 experiments are performed considering different water absorption levels on a single face.High-speed photography and ...To investigate the mechanism of rockburst prevention by spraying water onto the surrounding rocks,15 experiments are performed considering different water absorption levels on a single face.High-speed photography and acoustic emission(AE)system are used to monitor the rockburst process.The effect of water on sandstone rockburst and the prevention mechanism of water on sandstone rockburst are analyzed from the perspective of energy and failure mode.The results show that the higher the ab-sorption degree,the lower the intensity of the rockburst after absorbing water on single side of sand-stone.This is reflected in the fact that with the increase in the water absorption level,the ejection velocity of rockburst fragments is smaller,the depth of the rockburst pit is shallower,and the AE energy is smaller.Under the water absorption level of 100%,the magnitude of rockburst intensity changes from medium to slight.The prevention mechanism of water on sandstone rockburst is that water reduces the capacity of sandstone to store strain energy and accelerates the expansion of shear cracks,which is not conducive to the occurrence of plate cracking before rockburst,and destroys the conditions for rockburst incubation.展开更多
This study investigates the properties of exciton-polaritons in a two-dimensional(2D)hybrid organic-inorganic perovskite microcavity in the presence of optical Stark effect.Through both steady and dynamic state analys...This study investigates the properties of exciton-polaritons in a two-dimensional(2D)hybrid organic-inorganic perovskite microcavity in the presence of optical Stark effect.Through both steady and dynamic state analyses,strong coupling between excitons of perovskite and cavity photons is revealed,indicating the formation of polaritons in the perovskite microcavity.Besides,it is found that an external optical Stark pulse can induce energy shifts of excitons proportional to the pulse intensity,which modifies the dispersion characteristics of the polaritons.展开更多
Evaluation of Anti-aging Effect of QigongBased on the Theory That the Qigong Exer-cises Correct both Yin and Yang DeficienciesThe TCM theory holds that mainte-nance of a good health depends on the bal-ance of body yin...Evaluation of Anti-aging Effect of QigongBased on the Theory That the Qigong Exer-cises Correct both Yin and Yang DeficienciesThe TCM theory holds that mainte-nance of a good health depends on the bal-ance of body yin and yang which are con-stantly in motion and change.Premature ag-ing is mainly due to imbalance of yin andyang in the body.Years’ experimental展开更多
基金This study was supported by the Key Research Project Fund of Beijing University of Chinese Medicine(2021JYB2002001)the National Natural Science Foundation of Tibetan medicine Collabo-rative Innovation(82130113).
文摘Objective:To explore the anti-aging effects of chlorogenic acid(CGA)and the underlying mechanisms based on a Caenorhabditis elegans(C.elegans)model.Methods:The anti-agingactivityofCGAwasstudied basedon thebodylength,exercisebehavior,lipofuscin content,antioxidative stress ability,swallowing frequency,body-bending frequency,and head-swinging ability of C.elegans.Through DAF-16 nuclear translocation and SOD-3-GFP fluorescence experiments,the effects of CGA on ROS levels,antioxidant enzyme activities,MDA content,mutant-strain lifespan,and anti-aging molecular signaling pathways were explored,as well as the underlying mechanisms.Results:CGA improved multiple indices of the nematode:body length was increased(all P<0.001),head-swing frequency and body-bending frequency were increased(all P<0.05),nematode longevity was prolonged(P=0.0021),lipofuscin deposition in nematodes was slowed down(all P<0.001),the chemotaxis index was improved(P=0.0012),ROS levels were reduced(all P<.001),and SOD activity and MDA content were reduced(SOD:P=0.0017 between the low-concentration group and the control group,P<.001 between the high-concentration and medium-concentration groups and the control group;MDA:P=0.0135 between the low-concentration group and the control group,and P<0.001 between the high-concentration and medium-concentration groups and the control group).In addition,CGA also activated the DAF-16 transcription factor,promoted DAF-16 nuclear translocation under oxidative stress conditions(both P<0.001 between the high-concentration and medium-concentration groups and the control group),and increased SOD-3 gene expression in nematodes(all P<0.001).Conclusion:CGA plays an anti-aging role in C.elegans.The underlying mechanisms include activation of the insulin/IGF-1 signaling pathway and enhancement of DAF-16 activity.This study lays a foundation for further research into the anti-aging effects of CGA.
基金the Innovation and Entrepreneurship Training Program for College Students of Xiamen Medical College(202112631045).
文摘Flavonoids are secondary metabolites in plants and possess extensive pharmacological activities.Flavonoids have remarkable effect in prevent anti-tumor and cancer,but flavonoids can't be synthesized directly in the body.According to the different properties and structures of flavonoids in Traditional Chinese medicines,different extraction methods should be selected.Besides,flavonoids have good anti-aging effects.Based on three theories of modern aging,the anti-aging effect of flavonoids was discussed.It is expected to provide a beneficial reference for further development and utilization of natural flavonoid resources.
基金This study was supported by the National Natural Science Foundation of China(Grant No.42107020)the Science and Technology Project of Hunan Province(2020SK2028).
文摘To evaluate the potential anti-aging ability of Eucommia ulmoides,four characteristic components(chlorogenic acid,geniposidic acid,aucubin,quercetin)were selected to assess their effects on H_(2)O_(2)-induced oxidative damage model of human umbilical vein endothelial cell(HUVEC).Oxidative damage indexes,inflammatory factors,cell cycle,cell apoptosis,cell senescence,and their related proteins were analyzed by methyl thiazolyl tetrazolium(MTT)assay,enzyme-linked immunosorbent assay(ELISA),propidium iodide(PI)staining,annexin V-FITC/PI double staining,SAβ-galactosidase staining,and western blotting(WB).The results showed that H_(2)O_(2)-induced cell growth inhibition rate decreased as supplementation with characteristic components when compared to H_(2)O_(2) group.Meanwhile,the contents of antioxidant indexes(reactive oxygen species,lactate dehydrogenase,molondialdehyde,superoxide dismutase,glutathione),inflammatory factors(nuclear factor kappa-B,intercellular cell adhesion molecule-1,vascular cell adhesion protein 1),and functional factors(NO,Endothelin-1)in characteristic components treated groups improved if comparison with H_(2)O_(2) group,suggesting the characteristic components of E.ulmoides could alleviate H_(2)O_(2)-induced oxidative damage.Moreover,cell cycle,cell apoptosis,cell senescence,and their related proteins under characteristic components treatment exhibited a better effect than under H_(2)O_(2) treatment,implying the characteristic components could participate in anti-aging via multiple pathways.These results manifested that the characteristic components of E.ulmoides posses the capacity of anti-aging,which provided a basis for investigating the anti-aging ability of E.ulmoides itself.
基金National Science Foundation for China,Grant/Award Number:31672374PUMC Youth Fund,Grant/Award Number:2017310018CAMS Innovation Fund for Medical Sciences,Grant/Award Number:2016-12M-1-012
文摘Background: The time-related decline in regenerative capacity and organ homeostasis is a major feature of aging. Rehmannia glutinosa and Astragalus membranaceus have been used as traditional Chinese herbal medicines for enhanced immunity and prolonged life. However, the mechanism by which this herbal medicine slows aging is unknown. In this study, we investigated the mechanism of the herbal anti-aging effect.Methods: Mice were fed diets supplemented with R. glutinosa or A. membranaceus for 10 months; the control group was fed a standard diet. The phenotypes were evaluated using a grading score system and survival analysis. The percentages of the senescence phenotypes of hematopoietic stem cells(HSCs) were determined by fluorescence-activated cell sorting analysis. The function and the mechanism of HSCs were analyzed by clonogenic assay and the real-time polymerase chain reaction.Results: The anti-aging effect of R. glutinosa is due to the enhanced function of HSCs. Mice fed with R. glutinosa displayed characteristics of a slowed aging process,including decreased senescence and increased rate of survival. Flow cytometry analysis showed decreased numbers of Lin–Sca1^+c-kit–(LSK) cells, long-term HSCs(LT-HSCs) and short-term HSCs(ST-HSCs) in the R. glutinosa group. In vitro, clonogenic assays showed increased self-renewal ability of LT-HSCs from the R. glutinosa group as well as maintaining LSK quiescence through upregulated p18 expression. The R. glutinosa group also showed decreased reactive oxygen species levels and the percentage of β-gal^+ cells through downregulation of the cellular senescence-associated protein p53 and p16.Conclusion: Rehmannia glutinosa exerts anti-aging effects by maintaining the quiescence and decreasing the senescence of HSCs.
基金The project supported by the Construction Plan for Basic Condition Platform of Shanxi(2014091022)Program of Science and Technology of Shanxi Province(20140313008-14)
文摘OBJECTIVE Behavior research and urinary metabolomics method were applied to evaluate the anti-aging effects of Scutellaria baicalensis Georgi extract(SBG)in D-galactose-induced rats.METHODS Fifty rats were randomly divided into five groups(n=10in each group).Group 1served as vehicle control with injection of saline(vehicle control group),and the other groups of rats received daily subcutaneously injected with D-galactose(aged model group)at dose of 100mg·kg-1 for ten weeks,respectively.At the same time,rats in groups 3-5were intragastrically administered SBG 〔extracted twice with 60%(V/V)ethanol〕at doses of 50,100 and 200mg·kg-1 for ten weeks,and the rats of groups 1 and 2 were administrated an equal volume of the vehicle.At the tenth week,the learning and memory abilities were examined by Morris water maze.The urine was collected using metabolic cages and analyzed by high-resolution 1HNMR spectroscopy combined with multivariate statistical analyses.Principal component analysis(PCA)was utilized to classify and reveal the differences between the model group and control group.Then,the concentration of these differences was analyzed with t-test to determine whether SBG was possible to influence the metabolic pattern induced by D-galactose.RESULTS Compared with the vehicle control group,the D-galactose-treated aged model group markedly spent longer time(P<0.05)in finding the platform on days 3-5 in the spatial learning acquisition training of Morris water maze test.However,the escape latency was significantly reduced(P<0.05)by long-term administration of SBG(50,100 and 200mg·kg-1)compared with the D-galactose-treated aged model group on days 3-5.In the probe test,the D-galactose-treated aged model group made fewer(P<0.05)platform crossings and distance travelled in target quadrant(P<0.05)than the vehicle control group,and the SBG at doses of 50,100 and 200mg·kg-1 treatments groups could significantly increase(P<0.05)the number of times of crossing over the platform site.The SBG at doses of100 and 200mg·kg-1 treatments groups could significantly increase(P<0.05)the distance travelled in target quadrant compared with the D-galactose-treated aged model group.In addition,the significant difference in metabolic profiling was observed from model group compared with drug-dose group by using PCA,indicating the recovery effect of SBG on D-galactose induced aging rats.Some significantly changed metabolites like glycine,glucose and hexadecanoic acid have been identified.These biochemical changes are related to the the disturbance in aimno acid metabolism,energy metabolism and glycometabolism,which are helpful to further understanding the D-galactose induced aging rats and the therapeutic mechanism of SBG.CONCLUSION These results demonstrate that SBG extract has protective effect on the D-galactose-induced aging in rats.
文摘Boron is an ambitious fuel in energetic materials since its high heat release values,but its application is prohibited by low combustion efficiency and oxidization during storage.The polydopamine(PDA)was introduced into boron particles,investigating the impact of PDA content on the energetic behavior of boron.The results indicated that the PDA coating formed a fishing net structure on the surface of boron particles.The heat release results showed that the combustion calorific value of B@PDA was higher than that of the raw boron.Specifically,the actual combustion heat of boron powder in B@10%PDA increased by 38.08%.Meanwhile,the DSC peak temperature decreased by 100.65℃under similar oxidation rate compared to raw boron.Simultaneously,the B@PDA@AP and B@AP composites were prepared,and their combustion properties were evaluated.It was demonstrated that B@10%PDA@AP exhibited superior performance in terms of peak pressure and burning time,respectively.The peak pressure is 12.43 kPa more than B@AP and burning time is 2.22 times higher than B@AP.Therefore,the coating of PDA effectively inhibits the oxidization of boron during storage and enhances the energetic behavior of boron and corresponding composites.
基金financially supported by the Natural Science Foundation of Shandong Academy of Medical Sciences(No.2015-08)the Innovation Project of Shandong Academy of Medical Sciences and the Natural Science Open Foundation of State Key Laboratory of Bioactive Substance and Function of Natural Medicines(No.GTZK201503)
文摘The fruits of Paulownia catalpifolia Gong Tong are used as a Chinese folk herbal medicine for the treatment of enteritis, tonsillitis, bronchitis, and dysentery, etc. Our previous study has identified new C-geranylated flavanones with obvious anti-proliferative effects in lung cancer A549 cells. In the present study, a new C-geranylated flavone, paucatalinone C(1) and five known C-geranylated flavanones(2-6) were isolated. In addition, a total of 34 C-geranylated flavonoids were detected by HPLC-DAD-ESI-MS/MS coupling techniques from the CH_2Cl_2 extract of P. catalpifolia. Futhermore, anti-aging effects of isolated compounds were evaluated in vitro with premature senescent 2BS cells induced by H_2O_2. Phytochemical results indicated that P. catalpifolia was a natural resource of abundant C-geranylated flavonoids. Diplacone(3) and paucatalinone A(5) were the potent anti-aging agents in the premature senescent 2BS cells induced by H_2O_2 and the C-geranyl substituent may be an important factor because of its lipophilic character.
基金supported by the National Natural Science Foundation of China(42006094)by Fujian Natural Science Foundation(2019J05032).
文摘The purpose of this study was to explore the potential of the development and application of Paecilomyces hepiali,a fungus with edible and medicinal value,as a foodborne antioxidant and anti-aging agent.Its n-butanol extract(PHE)from rice cultures was selected for anti-aging experiment because of significant free radical scavenging activity in vitro.In vivo,PHE could significantly prolong the mean lifespan,50%survival days,and the maximum lifespan of Drosophila on a high-fat diet.It is amazing that the mean lifespan increased from 19.1 days to 32.9 days,50%survival days increased from 15.7 days to 34.3 days,and the maximum lifespan extended from 44.7 days to 52.7 days,when the high-fat female Drosophila model was fed with 10μg/mL PHE.Further research showed that PHE reduced the accumulation of peroxide products and increased the activity of antioxidant enzymes.Then,through antioxidant activity tracking,dimerumic acid(compound 1,the IC_(50) value of 3.4μg/mL on DPPH free radicals scavenging activity),4,5-dihydroxy-3-methoxypentanoic acid(compound 2,new compound),and thymidine(compound 3)were isolated from PHE.It is worth mentioning that dimerumic acid,the major antioxidant compound of PHE(content up to 3%),was discovered in P.hepiali for the first time.It was concluded that PHE showed excellent anti-aging activity at a very low concentration on fat diet-induced high fat Drosophila melanogaster,and dimerumic acid may be its main material basis.These results indicated that PHE had the potential to be developed as antioxidant and anti-aging agent in the healthcare industry.
基金Financial support for this research provided by the National Natural Science Foundation of China(22037002 and 81772689)the Program for Professor of Special Appointment(Eastern Scholar TP2018025,China)at Shanghai Institutions of Higher Learning+2 种基金the Innovative Research Team of High-level Local Universities in Shanghaithe Chinese Special Fund for State Key Laboratory of Bioreactor Engineering(2060204,China)Strains of Caenorhabditis elegans were provided by the CGC,which is funded by NIH Office of Research Infrastructure Programs(P40 OD010440)。
文摘Sulfonylureas are widely used oral anti-diabetic drugs.However,its long-term usage effects on patients’lifespan remain controversial,with no reports of influence on animal longevity.Hence,the anti-aging effects of chlorpropamide along with glimepiride,glibenclamide,and tolbutamide were studied with special emphasis on the interaction of chlorpropamide with mitochondrial ATP-sensitive K+(mito K-ATP)channels and mitochondrial complex II.Chlorpropamide delayed aging in Caenorhabditis elegans,human lung fibroblast MRC-5 cells and reduced doxorubicin-induced senescence in both MRC-5 cells and mice.In addition,the mitochondrial membrane potential and ATP levels were significantly increased in chlorpropamide-treated worms,which is consistent with the function of its reported targets,mito K-ATP channels.Increased levels of mitochondrial reactive oxygen species(mt ROS)were observed in chlorpropamide-treated worms.Moreover,the lifespan extension by chlorpropamide required complex II and increased mt ROS levels,indicating that chlorpropamide acts on complex II directly or indirectly via mito K-ATP to increase the production of mt ROS as a pro-longevity signal.This study provides mechanistic insight into the anti-aging effects of sulfonylureas in C.elegans.
文摘As post-WWII baby boomer approaching age 80, Anti-Aging Regenerative Cosmetology (AARC) has been developed and patented for beautifying and strengthening the human body using live cells;to enhance the appearance and function of various bodily parts to provide health and aestheticism of human being throughout life. It is a combined cosmetic and preventive medicine to intervene with and to correct the undesirable phenotypic expression of aging. The intrinsic properties of myoblasts and foreskin fibroblasts in development and regeneration are harnessed to formulate a genetic cell therapy program which is safe and efficacious as previously been tested in FDA Phase III clinical trials. Myoblasts are selected for strength development and foreskin fibroblasts for tenacity and smooth-to-the-touch. Both cell types are highly mitotic and non-carcinogenic. In additional to providing large quantities of nuclei as regenerative gene medicine, and of mitochondria as energy generators, myoblasts secret tumor necrosis factor alpha (TNF-α) for skin whitening and melanoma prevention. Myoblasts, because of their small size, spindle shape, and resilience, grow readily on collagen and laminin within wrinkles of skin surfaces, thus enhancing the color, luster, and texture of the skin “plated” with them. Alternatively, they can be injected subcutaneously as cell filler to reduce wrinkles. Intramuscular injection of myoblasts can augment the size, shape, consistency, tone, and strength of muscle groups, improving the lines, contours, and vitality to sculpt a youthful appearance. By improving cell genetics and organ functions, the program holds promise to sustain the human subject in good health and appearance, with a good quality of life and life prolongation.
基金financially supported by the National Key Research and Development Program of China(2021YFD2100904)the National Natural Science Foundation of China(31871729,32172147)+2 种基金the Modern Agriculture key Project of Jiangsu Province of China(BE2022317)the Modern Agricultural Industrial Technology System Construction Project of Jiangsu Province of China(JATS[2021]522)a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinations is more significant than a specific food component.This study investigated the lipid-lowering effect of highland barley polyphenols via lipase assay in vitro and HepG2 cells induced by oleic acid(OA).Five indexes,triglyceride(TG),total cholesterol(T-CHO),low density lipoprotein-cholesterol(LDL-C),aspartate aminotransferase(AST),and alanine aminotransferase(ALT),were used to evaluate the lipidlowering effect of highland barley extract.We also preliminary studied the lipid-lowering mechanism by Realtime fluorescent quantitative polymerase chain reaction(q PCR).The results indicated that highland barley extract contains many components with lipid-lowering effects,such as hyperoside and scoparone.In vitro,the lipase assay showed an 18.4%lipase inhibition rate when the additive contents of highland barley extract were 100μg/m L.The intracellular lipid-lowering effect of highland barley extract was examined using 0.25 mmol/L OA-induced HepG2 cells.The results showed that intracellular TG,LDL-C,and T-CHO content decreased by 34.4%,51.2%,and 18.4%,respectively.ALT and AST decreased by 51.6%and 20.7%compared with the untreated hyperlipidemic HepG2 cells.q PCR results showed that highland barley polyphenols could up-regulation the expression of lipid metabolism-related genes such as PPARγand Fabp4.
基金the National Natural Science Foundation of China(Nos.42161144008U21A2005+3 种基金U20A2085)the National Key Research and Development Program of China(2022YFF08018042022YFF08018032022YFF1300404)。
文摘Extreme climate has increasingly led to negative impacts on forest ecosystems globally,especially in semiarid areas where forest ecosystems are more vulnerable.However,it is poorly understood how tree growth is affected by different drought events.In 2006–2009,the larch plantations in the semiarid areas of Northwest China were negatively affected by four consecutive dry years,which was a very rare phenomenon that may occur frequently under future climate warming.In this study,we analyzed the effect of these consecutive dry years on tree growth based on the data of the tree rings in the dominant layer of the forest canopy on a larch plantation.We found that the tree-ring width index(RWI)in dry years was lower than that in normal years,and it experienced a rapidly decreasing trend from 2006 to 2009(slope=-0.139 year^(-1),r=-0.94)due to water supply deficits in those dry years.Drought induced legacy effects of tree growth reduction,and consecutive dry years corresponded with greater growth reductions and legacy effects.Growth reductions and legacy effects were significantly stronger in the third and fourth consecutive dry years than that of single dry year(p<0.05),which might have been due to the cumulative stress caused by consecutive dry years.Our results showed that larch trees experienced greater tree growth reduction due to consecutive dry years and their legacy effect,and the trees had lower recovery rates after consecutive dry years.Our results highlight that consecutive dry years pose a new threat to plantations under climate warming,and thus,the effect of climate extremes on tree growth should be considered in growth models in semiarid areas.
基金This work was supported by National Key R&D Program of China(2022YFB3605103)the National Natural Science Foundation of China(62204241,U22A2084,62121005,and 61827813)+3 种基金the Natural Science Foundation of Jilin Province(20230101345JC,20230101360JC,and 20230101107JC)the Youth Innovation Promotion Association of CAS(2023223)the Young Elite Scientist Sponsorship Program By CAST(YESS20200182)the CAS Talents Program(E30122E4M0).
文摘240 nm AlGaN-based micro-LEDs with different sizes are designed and fabricated.Then,the external quantum efficiency(EQE)and light extraction efficiency(LEE)are systematically investigated by comparing size and edge effects.Here,it is revealed that the peak optical output power increases by 81.83%with the size shrinking from 50.0 to 25.0μm.Thereinto,the LEE increases by 26.21%and the LEE enhancement mainly comes from the sidewall light extraction.Most notably,transversemagnetic(TM)mode light intensifies faster as the size shrinks due to the tilted mesa side-wall and Al reflector design.However,when it turns to 12.5μm sized micro-LEDs,the output power is lower than 25.0μm sized ones.The underlying mechanism is that even though protected by SiO2 passivation,the edge effect which leads to current leakage and Shockley-Read-Hall(SRH)recombination deteriorates rapidly with the size further shrinking.Moreover,the ratio of the p-contact area to mesa area is much lower,which deteriorates the p-type current spreading at the mesa edge.These findings show a role of thumb for the design of high efficiency micro-LEDs with wavelength below 250 nm,which will pave the way for wide applications of deep ultraviolet(DUV)micro-LEDs.
基金the Youth Growth Technology Project,Science and Technology Department of Jilin Province(20230508130RC)Bureau of Forestry and Landscaping of Changchun.
文摘Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban forests and improvement of function.To clarify the effect of two forest types with different urbanization intensities,we determined differences in vegetation composition and diversity,structural traits,and carbon stocks of 152 plots(20 m×20 m)in urban park forests in Changchun,which had the largest green quantity and carbon density effectiveness.We found that 1.1-fold thicker and healthier trees,and 1.6-to 2.0-fold higher,healthier,denser,and more various shrubs but with sparser trees and herbs occurred in the central urban forests(p<0.05)than in the outer forests.The conifer forests exhibited 30–70%obviously higher tree aboveground carbon sequestration(including stem and leaf)and 20%bigger trees,especially in the outer forests(p<0.05).In contrast,1.1-to 1.5-fold higher branch stocks,healthier and more diverse trees were found in broadleaved forests of both the inner and outer forests(p<0.05).Plant size and dominant species had similarly important roles in carbon stock improvement,especially big-sized woody plants and Pinus tabuliformis.In addition,a higher number of deciduous or needle species positively affected the broadleaved forest of the central urban area and conifer forest of the outer urban area,respectively.These findings can be used to guide precise management and accelerate the improvement of urban carbon function in Northeast China in the future.
基金the National Natural Science Foundation of China(Grant No.42174047 and No.42174036)the National Science Foundation Project for Outstanding Youth(No.42104034).
文摘This paper realizes the full-domain collaborative deployment of multiple interference sources of the global satellite navigation system(GNSS)and evaluates the deployment effect to enhance the ability to disturb the attacker and the capability to defend the GNSS during navigation countermeasures.Key evaluation indicators for the jamming effect of GNSS suppressive and deceptive jamming sources are first created,their evaluation models are built,and their detection procedures are sorted out,as the basis for determining the deployment principles.The principles for collaboratively deploying multi-jamming sources are developed to obtain the deployment structures(including the required number,structures in demand,and corresponding positions)of three single interference sources required by collaboratively deploying.Accordingly,simulation and hardware-in-loop testing results are presented to determine a rational configuration of the collaborative deployment of multi-jamming sources in the set situation and further realize the full-domain deployment of an interference network from ground,air to space.Varied evaluation indices for the deployment effect are finally developed to evaluate the deployment effect of the proposed configuration and further verify its reliability and rationality.
文摘Sickle cell disease (SCD) is a prevalent condition, particularly in the countries of sub-Saharan Africa, where the presence of specific genes associated with Malaria contributes to its high prevalence. Patients with sickle cell disease frequently experience painful episodes necessitating hospitalization, and their hemoglobin levels are typically lower than those of the general population. There are different treatment options available to manage complications, such as transfusing blood, hydroxyurea, and strong anti-pains. However, with all these treatments, patients still commonly experience pain crises and suffer from organ damage. Hydroxyurea, the sole approved medication for sickle cell anemia in developed and developing countries, is widely used in children despite being primarily indicated for adults. Multiple studies have demonstrated the efficacy of hydroxyurea in inducing HbF production in young children with SCD. Elevated HbF levels have been associated with improved clinical outcomes, including a reduction in vaso-occlusive crises, acute chest syndrome, and the need for blood transfusions. Furthermore, increased HbF levels have been shown to ameliorate disease-related organ damage, such as pulmonary hypertension and sickle cell retinopathy. The response to hydroxyurea treatment in young children with SCD is variable. Some patients achieve substantial increases in HbF levels and experience significant clinical benefits, while others may have a more modest response. Factors influencing the response include baseline HbF levels, genetic modifiers, treatment adherence, and dose optimization. Safety is a crucial consideration when using hydroxyurea in young children. Studies have shown that hydroxyurea is generally well-tolerated, with the most common adverse effects being myelosuppression, gastrointestinal symptoms, and dermatological manifestations. However,long-term effects and potential risks, such as renal dysfunction and reproductive impacts, require further investigation. The effectiveness of hydroxyurea in young children with SCD has been demonstrated in various clinical trials and observational studies. These studies have shown a significant reduction in disease-related complications and improved quality of life. However, optimal dosing, treatment duration, and long-term outcomes are still areas of ongoing research. This review focuses on recent studies investigating the benefits, effectiveness, responses, and safety of hydroxyurea in pediatric individuals diagnosed with sickle cell disease.
基金supported by the National Natural Science Foundation of China(Grant Nos.61405058 and 62075059)the Natural Science Foundation of Hunan Province(Grant Nos.2017JJ2048 and 2020JJ4161)+2 种基金the Scientific Research Foundation of Hunan Provincial Education Department(Grant No.21A0013)the Open Project of the State Key Laboratory of Advanced Optical Communication Systems and Networks of China(Grant No.2024GZKF20)the Guangdong Basic and Applied Basic Research Foundation(Grant No.2024A1515011353)。
文摘Hybrid skin-topological effect(HSTE)in non-Hermitian systems exhibits both the skin effect and topological protection,offering a novel mechanism for localization of topological edge states(TESs)in electrons,circuits,and photons.However,it remains unclear whether the HSTE can be realized in quasicrystals.
基金The financial support from the National Natural Science Foun-dation of China(Grant Nos.52074299 and 41941018)the Fundamental Research Funds for the Central Universities of China(Grant No.2023JCCXSB02)are gratefully acknowledged.
文摘To investigate the mechanism of rockburst prevention by spraying water onto the surrounding rocks,15 experiments are performed considering different water absorption levels on a single face.High-speed photography and acoustic emission(AE)system are used to monitor the rockburst process.The effect of water on sandstone rockburst and the prevention mechanism of water on sandstone rockburst are analyzed from the perspective of energy and failure mode.The results show that the higher the ab-sorption degree,the lower the intensity of the rockburst after absorbing water on single side of sand-stone.This is reflected in the fact that with the increase in the water absorption level,the ejection velocity of rockburst fragments is smaller,the depth of the rockburst pit is shallower,and the AE energy is smaller.Under the water absorption level of 100%,the magnitude of rockburst intensity changes from medium to slight.The prevention mechanism of water on sandstone rockburst is that water reduces the capacity of sandstone to store strain energy and accelerates the expansion of shear cracks,which is not conducive to the occurrence of plate cracking before rockburst,and destroys the conditions for rockburst incubation.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11974071 and 62375040)the Sichuan Science and Technology Program(Grant Nos.2022ZYD0108 and 2023JDRC0030).
文摘This study investigates the properties of exciton-polaritons in a two-dimensional(2D)hybrid organic-inorganic perovskite microcavity in the presence of optical Stark effect.Through both steady and dynamic state analyses,strong coupling between excitons of perovskite and cavity photons is revealed,indicating the formation of polaritons in the perovskite microcavity.Besides,it is found that an external optical Stark pulse can induce energy shifts of excitons proportional to the pulse intensity,which modifies the dispersion characteristics of the polaritons.
文摘Evaluation of Anti-aging Effect of QigongBased on the Theory That the Qigong Exer-cises Correct both Yin and Yang DeficienciesThe TCM theory holds that mainte-nance of a good health depends on the bal-ance of body yin and yang which are con-stantly in motion and change.Premature ag-ing is mainly due to imbalance of yin andyang in the body.Years’ experimental
