The aging characteristics of lithium-ion battery(LIB)under fast charging is investigated based on an electrochemical-thermal-mechanical(ETM)coupling model.Firstly,the ETM coupling model is established by COMSOL Multip...The aging characteristics of lithium-ion battery(LIB)under fast charging is investigated based on an electrochemical-thermal-mechanical(ETM)coupling model.Firstly,the ETM coupling model is established by COMSOL Multiphysics.Subsequently,a long cycle test was conducted to explore the aging characteristics of LIB.Specifically,the effects of charging(C)rate and cycle number on battery aging are analyzed in terms of nonuniform distribution of solid electrolyte interface(SEI),SEI formation,thermal stability and stress characteristics.The results indicate that the increases in C rate and cycling led to an increase in the degree of nonuniform distribution of SEI,and thus a consequent increase in the capacity loss due to the SEI formation.Meanwhile,the increases in C rate and cycle number also led to an increase in the heat generation and a decrease in the heat dissipation rate of the battery,respectively,which result in a decrease in the thermal stability of the electrode materials.In addition,the von Mises stress of the positive electrode material is higher than that of the negative electrode material as the cycling proceeds,with the positive electrode material exhibiting tensile deformation and the negative electrode material exhibiting compressive deformation.The available lithium ion concentration of the positive electrode is lower than that of the negative electrode,proving that the tensile-type fracture occurring in the positive material under long cycling dominated the capacity loss process.The aforementioned studies are helpful for researchers to further explore the aging behavior of LIB under fast charging and take corresponding preventive measures.展开更多
Declining cognitive abilities can be a concomitant of advanced age.As language is closely associated with cognitive abilities,changes in language abilities can be an important marker of changes in cognitive abilities....Declining cognitive abilities can be a concomitant of advanced age.As language is closely associated with cognitive abilities,changes in language abilities can be an important marker of changes in cognitive abilities.The current study is to review cognitive studies of language and aging by first identifying and exploring the major clusters and pivotal articles and then detecting emerging trends.Data of 3,266 articles on language and aging from 2013 to 2022 were collected from the Web of Science Core Collection database.Adopting Document Co-citation Analysis,Freeman’s betweenness centrality metric(Freeman,2002)and Kleinberg’s burst detection algorithm(Kleinberg,2002),we explored major clusters,pivotal articles and emerging trends in this field.Cognition appears to be the most remarkable cluster.Bilingualism,speech production,listening effort,and reading comprehension are other major active clusters in a certain period.The most recent active cluster concerns the studies of Alzheimer’s disease.Articles serving as pivotal points concentrate on cognitive studies of the Framework for Understanding Effortful Listening(FUEL),the new Ease of Language Understanding model(EUL)and a hierarchical multi-representational generative framework of language comprehension.The progress in statistical methods,the relationship between language and cognitive impairment and the relationship between language abilities and cognition are the emerging trends.These emerging trends will provide some insights into how cognitive abilities influence language abilities in aging.展开更多
The sex pheromone blend of a China strain of the black cutworm moth Agrotis ypsilon (Rottemberg) (Lepidoptera: Noctuidae) was investigated. Chemical analysis of pheromone gland extracts of 3-day-old females showe...The sex pheromone blend of a China strain of the black cutworm moth Agrotis ypsilon (Rottemberg) (Lepidoptera: Noctuidae) was investigated. Chemical analysis of pheromone gland extracts of 3-day-old females showed that individual isolated glands contained only very small amounts of pheromone. The high-resolution gas chromatography combined with mass spectrometry (GC-MS) analysis showed the presence of Cis-7-dodecenyl acetate (Z7-12:Ac, A), Cis-9-tetradecenyl acetate (Z9-14:Ac, B), Cis- 11-hexadecenyl acetate (Z 11 - 16 :Ac, C), Cis-8-dodecenyl acetate (Z8-12:Ac, E) and Cis-5-decenyl acetate (Z5-10:Ac, D) in biologically active pheromone gland extracts. An extract of one gland from a day 3 female gave the following values for the gland components: 0.245±0.098ng for Z7-12:Ac, 0.080±0.031ng for Z9-14:Ac, 0.089±0.033ng for Z11-16:Ac, 0.085±0.031ng for Z5-10:Ac, 0.105±0.065ng for Z8-12:Ac per female. The percentages of Z7-12:Ac, Z9-14:Ac, Z11-16:Ac, Z5-10:Ac and ZS-12:Ac in pheromone gland extracts from individual females were (meaniSE) 40.451±13.66, 13.176±5.279, 14.943±5.142, 14.392±6.10 and 17.225±9.792 respectively, and the percentages of Z7-12:Ac, Z9-14:Ac and Z11-16:Ac were 58.75±9.429, 18.91±7.539 and 22.34±7.209. Field trials indicated that each single component of sex pheromone was non-effective and captured no males. The lures baited with duality compound of AB (3 : 1) had a certain attraction to males, the mean captured number was 2.6. The attraction ability of the lures baited with ternary compound of ABC (3 : 1 :1) to males added significantly, the mean captured number per trap was 7.40, which was 2.8 times of duality compound of AB (3 : 1). The contents of sex pheromone could obviously affect its capture ability to males, the mean captured number was the highest at the dosage of 200 μg.展开更多
Four kinds of iron oxide pigments were added into wood-fiber/high-density-polyethylene composites (WF/HDPE) at three different concentrations, to determine the effects of pigments on the changes in the color and mec...Four kinds of iron oxide pigments were added into wood-fiber/high-density-polyethylene composites (WF/HDPE) at three different concentrations, to determine the effects of pigments on the changes in the color and mechanical properties of the composites before and after UV accelerated weathering. HDPE, wood fibers, pigments and other processing additives were dry-mixed in a high-speed mixer. The mixtures were extruded by two-step extrusion process with a self-designed twin-screw/single-screw extruder system. Color of the samples was determined according to CIE 1976 L^*a^*b^* system by a spec- trophotometer and the bending properties were tested to evaluate the mechanical properties before and after accelerated UV weathering. The result shows that the modulus of elasticity of WF/HDPE did not obvi- ously changed after incorporating with the pigments, but the bending strength increased. After accelerated aging for 2000 h, both color and mechanical properties significantly changed. Iron oxide red and black performed better than the other two pigments, and the pigments dosage of 2.28% in the composites is favourable.展开更多
Based on the structure of glass (or liquid) polymers consisting of α-domain, β-co-domain, and entanglement constituent chain networks, and the nonexponentially viscoelastic behavior, a “heterophase fluctuation” ...Based on the structure of glass (or liquid) polymers consisting of α-domain, β-co-domain, and entanglement constituent chain networks, and the nonexponentially viscoelastic behavior, a “heterophase fluctuation” model was proposed. It was found that the dynamics of cooperative rearrangement on the “fluidized domain” has a great shear rate, domain size, and temperature dependences. When the shear rate, domain size, and temperature dependences were taken account into the cooperatively localized rearrangement on the fluidized domain by the degradation of primary α-domain and the reformation of secondary β-co-domain constituent chains. A new dynamic theory of cooperatively localized rearrangement on the fluidized domain constituent chains with different size and different network chain length during physical and mechanical aging was established. The total viscoelastic free en-ergy of deformation resulting from the change in conformations of α-domain, β-co-domain, crytallite, crosslinked, and trapped entanglement constituent chains during aging processes was calculated by the combining method of kinetics and statistical mechanics. The constitu- tive equations and reduced stress relaxation modulus and creep compliances for three types of polymers were also derived. Finally, two reduced universal equations on creep compliance and stress relaxation modulus with a non-linear and two nonexponential parameters α and β were theoretically derived from the dynamic theory and a statistically extended mode coupling theory for double aging effects of polymers was developed. Results show that the two reduced universal equations have the same form as Kohlraush-Williams-Watts (K-W-W) stretched exponential function. The nonlinearity and the nonexponentiality are, respectively, originated from the memory effects of nonthermal and thermal history. The correlation of nonlinearity, α and β to the aging time, aging temperature, and the mesomorphic structure of fluidized domains was also established.展开更多
Objective: Past studies showed that tumor necrosis factor (TNF) assisted anti-tumor treatment and intensified the sensitivity of chemotherapy. However its clinical application has been curbed because of its low purity...Objective: Past studies showed that tumor necrosis factor (TNF) assisted anti-tumor treatment and intensified the sensitivity of chemotherapy. However its clinical application has been curbed because of its low purity, high dosage, and strong toxicity. The objective of present study is to evaluate the therapeutic effects and adverse reactions of recombinant mutant human tumor necrosis factor (rmhTNF) combined with chemotherapy in patients with advanced malignant tumor. Methods: 105 patients with advanced malignant tumor were randomly divided into trial group, 69 patients, and control group, 36 patients. rmhTNF was injected intramuscularly to the trial group at a dose of 4×106 U/m2, from the 1st to 7th days, the 11th to 17th days combined with chemotherapy course. The chemotherapy plan was as follows: CAP for patients with the NSCLC; FAM for patients with gastric cancer; FC for patients with colorectal cancer. One treatment cycle lasted for 21 days and two cycles were scheduled. The control group was given only the same chemotherapy as the trial group. Results: In the trial group there was 1 CR case and 12 PR cases, and the response rate was 13/69 (18.84%); in the control group 1 PR case, the response rate 1/36 (2.78%). The response rate in the trial group was significantly higher than that in the control group (P=0.022). The response rate for NSCLC in the trial group was 8/17 (47.06%), and 1/6 (16.67%) in the control group. The response rates for gastric cancer and colorectal cancer in the trial groups also were higher than those in the control groups. After the treatment the KPS was 89.00±9.92 in the trial group, and 84.17±8.84 in the control group, with a significant difference between the two groups (P=0.028). The adverse reactions of rmhTNF injection included: pain in the injection area, chill, hardening and swelling and redness in the injection area, fever, ostealgia and myosalgia, and cold-like symptoms. All these adverse reactions were mild and bearable. Conclusion: The administration of rmhTNF in combination with general chemotherapy is an effective and secure means in treating advanced malignant tumor.展开更多
A kinetic model of dielectric ageing is presented. The central finding of this investigation is that there is a power-law relationship between the local electric field concentration and the rate of defect-tip initiate...A kinetic model of dielectric ageing is presented. The central finding of this investigation is that there is a power-law relationship between the local electric field concentration and the rate of defect-tip initiated conducting crack growth. By applying such a power-law conducting crack growth rate expression to the evaluation of the life of solid dielectrics, the empirical classical ageing law of insulation materials can be derived theoretically as a lobical result. All the results are universal and agree with the experimental data of oxide films.展开更多
AIM: Mechanisms underlying the chemopreventive effects of cyclooxygenase (COX) inhibitors remain elusive. We have previously shown that celecoxib but not indomethacin could prevent carcinogen-induced gastric cancer de...AIM: Mechanisms underlying the chemopreventive effects of cyclooxygenase (COX) inhibitors remain elusive. We have previously shown that celecoxib but not indomethacin could prevent carcinogen-induced gastric cancer development in Wistar rats. This chemopreventive effect appeared to be independent of COX-2 and prostaglandin (PG) E2 suppression since the lowest PGE2 was obtained in indomethacin group.This study compared the cell kinetic changes in stomachs of rats after treatment with celecoxib (5, 10, 20 mg/(kg·d)) or indomethacin (3 mg/(kg·d)) to gain more insights into the chemopreventive mechanism.METHODS: The apoptosis and proliferation indexes in gastric tumor, adjacent non-cancer tissues and normal gastric tissues were determined. Apoptosis was quantified by apoptotic nuclei counting and TUNEL, whereas proliferation was determined by Ki67 immunostaining.RESULTS: Treatment with either celecoxib or indomethacin inhibited gastric tumor proliferation by more than 65% (P<0.02). However, celecoxib caused a dose-dependent increase in apoptosis (P<0.05) which was not seen in indomethacin-treated tumors (P = 0.54). The highest apoptosis to proliferation ratio was seen in tumors treated with celecoxib at 10 mg/(kg·d). Treatment with this dose of celecoxib was associated with the lowest incidence of gastric cancer development.CONCLUSION: Our findings suggest that the difference in chemopreventive effects of indomethacin and celecoxib in this animal model of gastric carcinogenesis is largely due to the differential cell kinetic changes, which does not correlate with the degree of COX-2 and PG suppression.展开更多
The precipitation behaviors of the Cu-Ni-Si alloys during aging were studied by analyzing the variations of electric conductivity.The Avrami-equation of phase transformation kinetics and the Avrami-equation of electri...The precipitation behaviors of the Cu-Ni-Si alloys during aging were studied by analyzing the variations of electric conductivity.The Avrami-equation of phase transformation kinetics and the Avrami-equation of electric conductivity during aging were established for Cu-Ni-Si alloys,on the basis of linear relationship between the electric conductivity and the volume fraction of precipitates,and the calculation results coincide well with the experiment ones.The transformation kinetics curves were established to characterize the aging process.The characteristics of precipitates in the supersaturated solid solution alloy aged at 723 K were established,and the results show that the precipitates areβ-Ni3Si andδ-Ni2Si phases.展开更多
1 Why is the demograpy important? In the half century 2000-2050,there will be a virtual tsunami of aging in the United States.The anticipated increase in the population older than age 65 is 140%,and for the population...1 Why is the demograpy important? In the half century 2000-2050,there will be a virtual tsunami of aging in the United States.The anticipated increase in the population older than age 65 is 140%,and for the population older than age 85,389%.More than half of the current U.S.population can anticipate living to age 80,with a contemporary life expectancy at age 75 of 11 years,and at age 85 of 6 years.展开更多
AIM:To investigate the change in expression of p53 ,Bcl-2 ,and Bax genes in human colon cancer cells transplanted into nude mice after hyperthermia,chemotherapy,radiotherapy,thermochemotherapy,thermoradiotherapy and t...AIM:To investigate the change in expression of p53 ,Bcl-2 ,and Bax genes in human colon cancer cells transplanted into nude mice after hyperthermia,chemotherapy,radiotherapy,thermochemotherapy,thermoradiotherapy and thermochemoradiotherapy. METHODS:Human colon cancer cell line (HT29) was transplanted into the hind limbs of nude mice. Under laboratory simulated conditions of hyperthermia (43℃,60 min),the actual radiation doses and doses of mitomycin C (MMC) were calculated in reference to the clinical radiotherapy for human rectal cancer and chemotherapy prescription for colon cancer. The mice were divided into 6 groups according to the treatment approaches:hyperthermia,chemotherapy,radiotherapy,thermochemotherapy,thermoradiotherapy,and thermochemoradiotherapy. The mice were sacrificed at different time points and the tumor tissue was taken for further procedures. The morphologic changes in membrane,cytoplasm and nuclei of tumor cells of p53,Bcl-2,and Bax after treatment,were observed by immunohistochemistry staining. RESULTS:All of the six treatment modalities down-regulated the expression of p53,Bcl-2 and up-regulated the expression of Bax at different levels. The combined therapy of hyperthermia,with chemotherapy,and/or irradiation showed a greater effect on down-regulating the expression of p53 (0.208 ± 0.009 vs 0.155 ± 0.0115,P < 0.01) and Bcl-2 (0.086 ± 0.010 vs 0.026 ± 0.0170,P < 0.01) and up-regulating Bax expression (0.091 ± 0.0013 vs 0.207 ± 0.027,P < 0.01) compared with any single therapy.CONCLUSION:Hyperthermia enhances the effect of radio-and chemotherapy on tumors by changing the expression of apoptosis genes,such as p53,Bcl-2 and Bax.展开更多
Three kinds of polymeric materials are taken as example for the verification of linear ex-trapolation method from unified master lines with reduced universal equations on creep and stress relaxation tests. The theoret...Three kinds of polymeric materials are taken as example for the verification of linear ex-trapolation method from unified master lines with reduced universal equations on creep and stress relaxation tests. The theoretical values of long-term mechanical behavior and lifetime for a cured epoxide, polypropylene, poly(methyl-methacrylate), and SBR rubber are directly evaluated with the universal equations on reduced creep compliance and reduced stress relax-ation modulus and are compared with their predicted values by the linear extrapolation from the unified master lines of creep and stress relaxation. The results show that the theoretical values of dimensional stability, bearing ability and lifetime are in an excellent agreement with the predicted values, it shows that the linear extrapolation method is more simple and reliable. The dependences of long-term mechanical behaviors and lifetime on the different aging times are discussed.展开更多
Aim To explore the reason that the antiarrhythmic effect of the extract oftraditional Chinese medicinal herb, matrine, is weaker than quinidine and verapamil by comparison ofthe effect and efficacy of matrine on vario...Aim To explore the reason that the antiarrhythmic effect of the extract oftraditional Chinese medicinal herb, matrine, is weaker than quinidine and verapamil by comparison ofthe effect and efficacy of matrine on various kinds of transmembrane ionic currents with those ofquinidine and verapamil; and to demonstrate the best targets for antiarrhythmic drugs. MethodsWhole-cell patch-clamp techniques were used to record the action potential and ionic currents insingle cells of rat ventricular myocytes. Aconitine was used to induce the changes of ioniccurrents, then study the effects of matrine and quinidine, verapamil on aconitine-induced unbalancedchannel currents and action potential. Results Aconitine 1 μmol·L^(-1) induced significantchanges in transmembrane currents and action potential in single cells of rat ventricular myocytes.APD was significantly prolonged by aconitine. Simultaneously, aconitine increased sodium, L-typecalcium and inward rectifier potassium currents. Matrine 100 μmol· L^(-1) reversed theaconitine-induced changes of sodium current (I_(Na)) from (-70.2+- 10.5) pA/pF to ( - 39.6+-4.0)pA/pF(n = 5, P < 0.05 vs aconitine); L-type calcium current (I_(Ca-L)) from (20.4+- 3.8) pA/pF to (- 12.9+- 2.9) pA/pF ( n = 6, P < 0.01); the inward rectifier potassium current (I_(k1) ) from (-32.2+- 1.08) pA/pF to ( -24.0+-3.4) pA/pF (n = 6, P < 0.01), and action potential duration. Thereversal effects of quinidine and verapamil on aconitine-induced changes of APD and ionic currentswere more marked than matrine. Conclusion Aco-nitine significantly disturbs the normal equilibriumof ion channels in ventricular myocytes. It induces changes of I_(Na), I_(Ca-L), I_(K1) andprolongation of action potential duration. Matrine at concentration 50 or 100 μmol·L^(-1)statistically significantly suppresses aconitine-induced changes of APD and ionic currents. Thepotency and efficacy of inhibitory effect of matrine are markedly weaker than those of commonly usedverapamil and quinidine.展开更多
Patients older than 65 years are the fastest growing segment of the cancer population. It is estimated that within 20 years over 75% of cases and 85% of deaths from colorectal cancer (CRC) will be in this setting. Con...Patients older than 65 years are the fastest growing segment of the cancer population. It is estimated that within 20 years over 75% of cases and 85% of deaths from colorectal cancer (CRC) will be in this setting. Concerns about cancer treatment in the elderly relate to comorbidities, which increase proportionally with age, physiological changes associated with aging which may influence drug metabolism and toxicity, and diminishing life expectancy, which particularly impacts decisions surrounding the benefits of adjuvant therapies. Over the last 10 years, significant improvements in the treatment of advanced CRC with combination therapy have been made. The randomized trials which have defined these improvements did not exclude elderly patients. However, the median age of patients in these trials has generally been approximately 60 years. Thus, it appears that some degree of selection is involved with younger and presumably fitter patients being the subjects in most of the pivotal trials. The availability of new molecularly targeted agents and newly improved existing agents has expanded the range of treatment options available. This variety gives greater flexibility in dealing with different subsets of patients, such as the elderly. However, some fit elderly patients seem to tolerate combination therapy reasonably well, while studies on unfit elderly subjects are needed.展开更多
AIM:To examine whether the ob/ob mouse model of obesity is accompanied by enteric nervous system ab-normalities such as altered motility METHODS:The study examined the distribution of the P2X 2 receptor (P2X 2 R) in m...AIM:To examine whether the ob/ob mouse model of obesity is accompanied by enteric nervous system ab-normalities such as altered motility METHODS:The study examined the distribution of the P2X 2 receptor (P2X 2 R) in myenteric neurons of female ob/ob mice. Specifically, we used immunohistochemistry to analyze the co-expression of the P2X 2 R with neuronal nitric oxide synthase (nNOS), choline acetyltrans-ferase (ChAT), and calretinin (CalR) in neurons of the small intestine myenteric plexus in ob/ob and control female mice In these sections, we used scanning confocal microscopy to analyze the co-localization of these markers as well as the neuronal density (cm 2 ) and area profile (μm2) of P2X 2 R-positive neurons In addition, enteric neurons were labeled using the nicotinamide adenine dinucleotide (NA H) diaphorase method and analyzed with light microscopy as an alternate means by which to analyze neuronal density and areaRESULTS:In the present study, we observed a 29 6% increase in the body weight of the ob/ob animals (OG) compared to the control group (CG) In addition, the average small intestine area was increased by approxi-mately 29 6% in the OG compared to the CG Immu-noreactivity (IR) for the P2X 2 R, nNOS, ChAT and CalR was detectable in the myenteric plexus, as well as in the smooth muscle, in both groups This IR appeared to be mainly cytoplasmic and was also associated with the cell membrane of the myenteric plexus neurons, where it outlined the neuronal cell bodies and their processes P2X 2 R-IR was observed to co-localize 100% with that for nNOS, ChAT and CalR in neurons of both groups In the ob/ob group, however, we observed that the neuronal density (neuron/cm 2 ) of P2X 2 R-IR cells was in-creased by 62% compared to CG, while that of NOS-IR and ChAT-IR neurons was reduced by 49% and 57%, respectively, compared to control mice The neuronal density of CalR-IR neurons was not different between the groups Morphometric studies further demonstrated that the cell body profile area (μm2) of nNOS-IR, ChAT-IR and CalR-IR neurons was increased by 34%, 20% and 55%, respectively, in the OG compared to controls Staining for NA H diaphorase activity is widely used to detect alterations in the enteric nervous system; however, our qualitative examination of NA H-diaphorase positive neurons in the myenteric ganglia revealed an overall similarity between the two groups CONCLUSION:We demonstrate increases in P2X2R expression and alterations in nNOS, ChAT and CalR IR in ileal myenteric neurons of female ob/ob mice compared to wild-type controls.展开更多
Achillea millefolium (Asteraceae) is a permanent herb highly recognized in traditional medicine for its anti-oxidant and anti-inflammation properties. However, studies on phytochemical constituents of A. millefoli...Achillea millefolium (Asteraceae) is a permanent herb highly recognized in traditional medicine for its anti-oxidant and anti-inflammation properties. However, studies on phytochemical constituents of A. millefolium underlying these properties are scarce. The present work focuses on examining the effect of methanol extract of A. millefolium L. on total and differential blood cells account on albino male mice. The results showed the methanol extract increased the account of lymphocyte, and monocyte cells, and total account as well as this extract showed high decrease in the oxidative stress of MTX after the interfere between the extract and MTX due to increase in the leucocyte cells compared with controls. Concluded from these results that methanol extract of A. millefolium has ability enhancement in leucocyte cells in the blood and it has detoxification effect of MTX.展开更多
The clinical characteristics of undifferentiated(embryonal) sarcoma of the liver(UESL) were investigated and the best treatment modalities were recommended.Both histology and immuno-histochemistry demonstrated the cel...The clinical characteristics of undifferentiated(embryonal) sarcoma of the liver(UESL) were investigated and the best treatment modalities were recommended.Both histology and immuno-histochemistry demonstrated the cellular features of this peculiar tumor.The tumor size was 12 cm × 9 cm × 8 cm in the right liver lobe.The patient underwent surgical resection of the tumor.The postoperative recovery was uneventful and she died eight months after diagnosis.The tumor showed mixed spindle and polygonal cells within the myxoid matrix.Some tumor cells contained eosinophilic hyaline globules that were positive for resistant diastase.Immunohistochemistry showed positive vimentin.Stellate and spindle cells were positively stained with alpha-1-antichymotrypsin(AACT) and CD68.This case indicates that UESL is not obviously differentiated in old-aged adults.展开更多
Predicting the lifetime of polymeric insulators is one of the most important research topics in studying the life cycle of high voltage insulators in the power transmission and distribution networks. HTV (high temper...Predicting the lifetime of polymeric insulators is one of the most important research topics in studying the life cycle of high voltage insulators in the power transmission and distribution networks. HTV (high temperature vulcanized) silicone rubber is a high performance dielectric material used within electrical power equipment, in particular transmission and distribution insulators. In this paper, we proposed a new approach using the Newton's method and Lagrange method to predict the aging of HTV silicone rubber that are subjected to multiple stress conditions. Concentration of chemical elements such as carbon, oxygen, silicon and aluminum were obtained and evaluated using a SEM (scanning electron microscope) with EDS (energy dispersive X-ray spectroscopy). Curve fitting using the Newton's and Lagrange interpolation methods yield useful linear interpolation equations that describe the aging characteristic of the specimens under study. This approach can be applied to predict the change in chemical concentration of polymeric insulators over the life cycle with good accuracy.展开更多
基金funded by the National Natural Science Foundation of China(Grant No.12272217)。
文摘The aging characteristics of lithium-ion battery(LIB)under fast charging is investigated based on an electrochemical-thermal-mechanical(ETM)coupling model.Firstly,the ETM coupling model is established by COMSOL Multiphysics.Subsequently,a long cycle test was conducted to explore the aging characteristics of LIB.Specifically,the effects of charging(C)rate and cycle number on battery aging are analyzed in terms of nonuniform distribution of solid electrolyte interface(SEI),SEI formation,thermal stability and stress characteristics.The results indicate that the increases in C rate and cycling led to an increase in the degree of nonuniform distribution of SEI,and thus a consequent increase in the capacity loss due to the SEI formation.Meanwhile,the increases in C rate and cycle number also led to an increase in the heat generation and a decrease in the heat dissipation rate of the battery,respectively,which result in a decrease in the thermal stability of the electrode materials.In addition,the von Mises stress of the positive electrode material is higher than that of the negative electrode material as the cycling proceeds,with the positive electrode material exhibiting tensile deformation and the negative electrode material exhibiting compressive deformation.The available lithium ion concentration of the positive electrode is lower than that of the negative electrode,proving that the tensile-type fracture occurring in the positive material under long cycling dominated the capacity loss process.The aforementioned studies are helpful for researchers to further explore the aging behavior of LIB under fast charging and take corresponding preventive measures.
文摘Declining cognitive abilities can be a concomitant of advanced age.As language is closely associated with cognitive abilities,changes in language abilities can be an important marker of changes in cognitive abilities.The current study is to review cognitive studies of language and aging by first identifying and exploring the major clusters and pivotal articles and then detecting emerging trends.Data of 3,266 articles on language and aging from 2013 to 2022 were collected from the Web of Science Core Collection database.Adopting Document Co-citation Analysis,Freeman’s betweenness centrality metric(Freeman,2002)and Kleinberg’s burst detection algorithm(Kleinberg,2002),we explored major clusters,pivotal articles and emerging trends in this field.Cognition appears to be the most remarkable cluster.Bilingualism,speech production,listening effort,and reading comprehension are other major active clusters in a certain period.The most recent active cluster concerns the studies of Alzheimer’s disease.Articles serving as pivotal points concentrate on cognitive studies of the Framework for Understanding Effortful Listening(FUEL),the new Ease of Language Understanding model(EUL)and a hierarchical multi-representational generative framework of language comprehension.The progress in statistical methods,the relationship between language and cognitive impairment and the relationship between language abilities and cognition are the emerging trends.These emerging trends will provide some insights into how cognitive abilities influence language abilities in aging.
基金Science and Technology Fund of Guizhou Province (2006-2048)
文摘The sex pheromone blend of a China strain of the black cutworm moth Agrotis ypsilon (Rottemberg) (Lepidoptera: Noctuidae) was investigated. Chemical analysis of pheromone gland extracts of 3-day-old females showed that individual isolated glands contained only very small amounts of pheromone. The high-resolution gas chromatography combined with mass spectrometry (GC-MS) analysis showed the presence of Cis-7-dodecenyl acetate (Z7-12:Ac, A), Cis-9-tetradecenyl acetate (Z9-14:Ac, B), Cis- 11-hexadecenyl acetate (Z 11 - 16 :Ac, C), Cis-8-dodecenyl acetate (Z8-12:Ac, E) and Cis-5-decenyl acetate (Z5-10:Ac, D) in biologically active pheromone gland extracts. An extract of one gland from a day 3 female gave the following values for the gland components: 0.245±0.098ng for Z7-12:Ac, 0.080±0.031ng for Z9-14:Ac, 0.089±0.033ng for Z11-16:Ac, 0.085±0.031ng for Z5-10:Ac, 0.105±0.065ng for Z8-12:Ac per female. The percentages of Z7-12:Ac, Z9-14:Ac, Z11-16:Ac, Z5-10:Ac and ZS-12:Ac in pheromone gland extracts from individual females were (meaniSE) 40.451±13.66, 13.176±5.279, 14.943±5.142, 14.392±6.10 and 17.225±9.792 respectively, and the percentages of Z7-12:Ac, Z9-14:Ac and Z11-16:Ac were 58.75±9.429, 18.91±7.539 and 22.34±7.209. Field trials indicated that each single component of sex pheromone was non-effective and captured no males. The lures baited with duality compound of AB (3 : 1) had a certain attraction to males, the mean captured number was 2.6. The attraction ability of the lures baited with ternary compound of ABC (3 : 1 :1) to males added significantly, the mean captured number per trap was 7.40, which was 2.8 times of duality compound of AB (3 : 1). The contents of sex pheromone could obviously affect its capture ability to males, the mean captured number was the highest at the dosage of 200 μg.
基金supported by the National Natural Science Foundation of China (30671644, 30771680)
文摘Four kinds of iron oxide pigments were added into wood-fiber/high-density-polyethylene composites (WF/HDPE) at three different concentrations, to determine the effects of pigments on the changes in the color and mechanical properties of the composites before and after UV accelerated weathering. HDPE, wood fibers, pigments and other processing additives were dry-mixed in a high-speed mixer. The mixtures were extruded by two-step extrusion process with a self-designed twin-screw/single-screw extruder system. Color of the samples was determined according to CIE 1976 L^*a^*b^* system by a spec- trophotometer and the bending properties were tested to evaluate the mechanical properties before and after accelerated UV weathering. The result shows that the modulus of elasticity of WF/HDPE did not obvi- ously changed after incorporating with the pigments, but the bending strength increased. After accelerated aging for 2000 h, both color and mechanical properties significantly changed. Iron oxide red and black performed better than the other two pigments, and the pigments dosage of 2.28% in the composites is favourable.
基金ACKNOWLEDGMENT This work was supported by the National Natural Science Foundation of China (No.50973007).
文摘Based on the structure of glass (or liquid) polymers consisting of α-domain, β-co-domain, and entanglement constituent chain networks, and the nonexponentially viscoelastic behavior, a “heterophase fluctuation” model was proposed. It was found that the dynamics of cooperative rearrangement on the “fluidized domain” has a great shear rate, domain size, and temperature dependences. When the shear rate, domain size, and temperature dependences were taken account into the cooperatively localized rearrangement on the fluidized domain by the degradation of primary α-domain and the reformation of secondary β-co-domain constituent chains. A new dynamic theory of cooperatively localized rearrangement on the fluidized domain constituent chains with different size and different network chain length during physical and mechanical aging was established. The total viscoelastic free en-ergy of deformation resulting from the change in conformations of α-domain, β-co-domain, crytallite, crosslinked, and trapped entanglement constituent chains during aging processes was calculated by the combining method of kinetics and statistical mechanics. The constitu- tive equations and reduced stress relaxation modulus and creep compliances for three types of polymers were also derived. Finally, two reduced universal equations on creep compliance and stress relaxation modulus with a non-linear and two nonexponential parameters α and β were theoretically derived from the dynamic theory and a statistically extended mode coupling theory for double aging effects of polymers was developed. Results show that the two reduced universal equations have the same form as Kohlraush-Williams-Watts (K-W-W) stretched exponential function. The nonlinearity and the nonexponentiality are, respectively, originated from the memory effects of nonthermal and thermal history. The correlation of nonlinearity, α and β to the aging time, aging temperature, and the mesomorphic structure of fluidized domains was also established.
文摘Objective: Past studies showed that tumor necrosis factor (TNF) assisted anti-tumor treatment and intensified the sensitivity of chemotherapy. However its clinical application has been curbed because of its low purity, high dosage, and strong toxicity. The objective of present study is to evaluate the therapeutic effects and adverse reactions of recombinant mutant human tumor necrosis factor (rmhTNF) combined with chemotherapy in patients with advanced malignant tumor. Methods: 105 patients with advanced malignant tumor were randomly divided into trial group, 69 patients, and control group, 36 patients. rmhTNF was injected intramuscularly to the trial group at a dose of 4×106 U/m2, from the 1st to 7th days, the 11th to 17th days combined with chemotherapy course. The chemotherapy plan was as follows: CAP for patients with the NSCLC; FAM for patients with gastric cancer; FC for patients with colorectal cancer. One treatment cycle lasted for 21 days and two cycles were scheduled. The control group was given only the same chemotherapy as the trial group. Results: In the trial group there was 1 CR case and 12 PR cases, and the response rate was 13/69 (18.84%); in the control group 1 PR case, the response rate 1/36 (2.78%). The response rate in the trial group was significantly higher than that in the control group (P=0.022). The response rate for NSCLC in the trial group was 8/17 (47.06%), and 1/6 (16.67%) in the control group. The response rates for gastric cancer and colorectal cancer in the trial groups also were higher than those in the control groups. After the treatment the KPS was 89.00±9.92 in the trial group, and 84.17±8.84 in the control group, with a significant difference between the two groups (P=0.028). The adverse reactions of rmhTNF injection included: pain in the injection area, chill, hardening and swelling and redness in the injection area, fever, ostealgia and myosalgia, and cold-like symptoms. All these adverse reactions were mild and bearable. Conclusion: The administration of rmhTNF in combination with general chemotherapy is an effective and secure means in treating advanced malignant tumor.
文摘A kinetic model of dielectric ageing is presented. The central finding of this investigation is that there is a power-law relationship between the local electric field concentration and the rate of defect-tip initiated conducting crack growth. By applying such a power-law conducting crack growth rate expression to the evaluation of the life of solid dielectrics, the empirical classical ageing law of insulation materials can be derived theoretically as a lobical result. All the results are universal and agree with the experimental data of oxide films.
基金Supported by an unrestricted grant From the Hong Kong Society of Digestive Endoscopy and the Natural Science Foundation of Guangdong Province of China(No.010713)
文摘AIM: Mechanisms underlying the chemopreventive effects of cyclooxygenase (COX) inhibitors remain elusive. We have previously shown that celecoxib but not indomethacin could prevent carcinogen-induced gastric cancer development in Wistar rats. This chemopreventive effect appeared to be independent of COX-2 and prostaglandin (PG) E2 suppression since the lowest PGE2 was obtained in indomethacin group.This study compared the cell kinetic changes in stomachs of rats after treatment with celecoxib (5, 10, 20 mg/(kg·d)) or indomethacin (3 mg/(kg·d)) to gain more insights into the chemopreventive mechanism.METHODS: The apoptosis and proliferation indexes in gastric tumor, adjacent non-cancer tissues and normal gastric tissues were determined. Apoptosis was quantified by apoptotic nuclei counting and TUNEL, whereas proliferation was determined by Ki67 immunostaining.RESULTS: Treatment with either celecoxib or indomethacin inhibited gastric tumor proliferation by more than 65% (P<0.02). However, celecoxib caused a dose-dependent increase in apoptosis (P<0.05) which was not seen in indomethacin-treated tumors (P = 0.54). The highest apoptosis to proliferation ratio was seen in tumors treated with celecoxib at 10 mg/(kg·d). Treatment with this dose of celecoxib was associated with the lowest incidence of gastric cancer development.CONCLUSION: Our findings suggest that the difference in chemopreventive effects of indomethacin and celecoxib in this animal model of gastric carcinogenesis is largely due to the differential cell kinetic changes, which does not correlate with the degree of COX-2 and PG suppression.
基金Project(2006AA03Z517) supported by the National High-tech Research and Development Program of ChinaProject(08MX15) supported by the Mittal Programs of Central South University, China
文摘The precipitation behaviors of the Cu-Ni-Si alloys during aging were studied by analyzing the variations of electric conductivity.The Avrami-equation of phase transformation kinetics and the Avrami-equation of electric conductivity during aging were established for Cu-Ni-Si alloys,on the basis of linear relationship between the electric conductivity and the volume fraction of precipitates,and the calculation results coincide well with the experiment ones.The transformation kinetics curves were established to characterize the aging process.The characteristics of precipitates in the supersaturated solid solution alloy aged at 723 K were established,and the results show that the precipitates areβ-Ni3Si andδ-Ni2Si phases.
文摘1 Why is the demograpy important? In the half century 2000-2050,there will be a virtual tsunami of aging in the United States.The anticipated increase in the population older than age 65 is 140%,and for the population older than age 85,389%.More than half of the current U.S.population can anticipate living to age 80,with a contemporary life expectancy at age 75 of 11 years,and at age 85 of 6 years.
基金Supported by the Clinical Research Foundation of Tianjin Medical University, No. 2002KY18
文摘AIM:To investigate the change in expression of p53 ,Bcl-2 ,and Bax genes in human colon cancer cells transplanted into nude mice after hyperthermia,chemotherapy,radiotherapy,thermochemotherapy,thermoradiotherapy and thermochemoradiotherapy. METHODS:Human colon cancer cell line (HT29) was transplanted into the hind limbs of nude mice. Under laboratory simulated conditions of hyperthermia (43℃,60 min),the actual radiation doses and doses of mitomycin C (MMC) were calculated in reference to the clinical radiotherapy for human rectal cancer and chemotherapy prescription for colon cancer. The mice were divided into 6 groups according to the treatment approaches:hyperthermia,chemotherapy,radiotherapy,thermochemotherapy,thermoradiotherapy,and thermochemoradiotherapy. The mice were sacrificed at different time points and the tumor tissue was taken for further procedures. The morphologic changes in membrane,cytoplasm and nuclei of tumor cells of p53,Bcl-2,and Bax after treatment,were observed by immunohistochemistry staining. RESULTS:All of the six treatment modalities down-regulated the expression of p53,Bcl-2 and up-regulated the expression of Bax at different levels. The combined therapy of hyperthermia,with chemotherapy,and/or irradiation showed a greater effect on down-regulating the expression of p53 (0.208 ± 0.009 vs 0.155 ± 0.0115,P < 0.01) and Bcl-2 (0.086 ± 0.010 vs 0.026 ± 0.0170,P < 0.01) and up-regulating Bax expression (0.091 ± 0.0013 vs 0.207 ± 0.027,P < 0.01) compared with any single therapy.CONCLUSION:Hyperthermia enhances the effect of radio-and chemotherapy on tumors by changing the expression of apoptosis genes,such as p53,Bcl-2 and Bax.
基金This work was supported by the National Natural Science Foundation of China (No.50973007).
文摘Three kinds of polymeric materials are taken as example for the verification of linear ex-trapolation method from unified master lines with reduced universal equations on creep and stress relaxation tests. The theoretical values of long-term mechanical behavior and lifetime for a cured epoxide, polypropylene, poly(methyl-methacrylate), and SBR rubber are directly evaluated with the universal equations on reduced creep compliance and reduced stress relax-ation modulus and are compared with their predicted values by the linear extrapolation from the unified master lines of creep and stress relaxation. The results show that the theoretical values of dimensional stability, bearing ability and lifetime are in an excellent agreement with the predicted values, it shows that the linear extrapolation method is more simple and reliable. The dependences of long-term mechanical behaviors and lifetime on the different aging times are discussed.
文摘Aim To explore the reason that the antiarrhythmic effect of the extract oftraditional Chinese medicinal herb, matrine, is weaker than quinidine and verapamil by comparison ofthe effect and efficacy of matrine on various kinds of transmembrane ionic currents with those ofquinidine and verapamil; and to demonstrate the best targets for antiarrhythmic drugs. MethodsWhole-cell patch-clamp techniques were used to record the action potential and ionic currents insingle cells of rat ventricular myocytes. Aconitine was used to induce the changes of ioniccurrents, then study the effects of matrine and quinidine, verapamil on aconitine-induced unbalancedchannel currents and action potential. Results Aconitine 1 μmol·L^(-1) induced significantchanges in transmembrane currents and action potential in single cells of rat ventricular myocytes.APD was significantly prolonged by aconitine. Simultaneously, aconitine increased sodium, L-typecalcium and inward rectifier potassium currents. Matrine 100 μmol· L^(-1) reversed theaconitine-induced changes of sodium current (I_(Na)) from (-70.2+- 10.5) pA/pF to ( - 39.6+-4.0)pA/pF(n = 5, P < 0.05 vs aconitine); L-type calcium current (I_(Ca-L)) from (20.4+- 3.8) pA/pF to (- 12.9+- 2.9) pA/pF ( n = 6, P < 0.01); the inward rectifier potassium current (I_(k1) ) from (-32.2+- 1.08) pA/pF to ( -24.0+-3.4) pA/pF (n = 6, P < 0.01), and action potential duration. Thereversal effects of quinidine and verapamil on aconitine-induced changes of APD and ionic currentswere more marked than matrine. Conclusion Aco-nitine significantly disturbs the normal equilibriumof ion channels in ventricular myocytes. It induces changes of I_(Na), I_(Ca-L), I_(K1) andprolongation of action potential duration. Matrine at concentration 50 or 100 μmol·L^(-1)statistically significantly suppresses aconitine-induced changes of APD and ionic currents. Thepotency and efficacy of inhibitory effect of matrine are markedly weaker than those of commonly usedverapamil and quinidine.
文摘Patients older than 65 years are the fastest growing segment of the cancer population. It is estimated that within 20 years over 75% of cases and 85% of deaths from colorectal cancer (CRC) will be in this setting. Concerns about cancer treatment in the elderly relate to comorbidities, which increase proportionally with age, physiological changes associated with aging which may influence drug metabolism and toxicity, and diminishing life expectancy, which particularly impacts decisions surrounding the benefits of adjuvant therapies. Over the last 10 years, significant improvements in the treatment of advanced CRC with combination therapy have been made. The randomized trials which have defined these improvements did not exclude elderly patients. However, the median age of patients in these trials has generally been approximately 60 years. Thus, it appears that some degree of selection is involved with younger and presumably fitter patients being the subjects in most of the pivotal trials. The availability of new molecularly targeted agents and newly improved existing agents has expanded the range of treatment options available. This variety gives greater flexibility in dealing with different subsets of patients, such as the elderly. However, some fit elderly patients seem to tolerate combination therapy reasonably well, while studies on unfit elderly subjects are needed.
基金Supported by So Paulo Research Foundation (FAPESP), Proc 05/04752-0
文摘AIM:To examine whether the ob/ob mouse model of obesity is accompanied by enteric nervous system ab-normalities such as altered motility METHODS:The study examined the distribution of the P2X 2 receptor (P2X 2 R) in myenteric neurons of female ob/ob mice. Specifically, we used immunohistochemistry to analyze the co-expression of the P2X 2 R with neuronal nitric oxide synthase (nNOS), choline acetyltrans-ferase (ChAT), and calretinin (CalR) in neurons of the small intestine myenteric plexus in ob/ob and control female mice In these sections, we used scanning confocal microscopy to analyze the co-localization of these markers as well as the neuronal density (cm 2 ) and area profile (μm2) of P2X 2 R-positive neurons In addition, enteric neurons were labeled using the nicotinamide adenine dinucleotide (NA H) diaphorase method and analyzed with light microscopy as an alternate means by which to analyze neuronal density and areaRESULTS:In the present study, we observed a 29 6% increase in the body weight of the ob/ob animals (OG) compared to the control group (CG) In addition, the average small intestine area was increased by approxi-mately 29 6% in the OG compared to the CG Immu-noreactivity (IR) for the P2X 2 R, nNOS, ChAT and CalR was detectable in the myenteric plexus, as well as in the smooth muscle, in both groups This IR appeared to be mainly cytoplasmic and was also associated with the cell membrane of the myenteric plexus neurons, where it outlined the neuronal cell bodies and their processes P2X 2 R-IR was observed to co-localize 100% with that for nNOS, ChAT and CalR in neurons of both groups In the ob/ob group, however, we observed that the neuronal density (neuron/cm 2 ) of P2X 2 R-IR cells was in-creased by 62% compared to CG, while that of NOS-IR and ChAT-IR neurons was reduced by 49% and 57%, respectively, compared to control mice The neuronal density of CalR-IR neurons was not different between the groups Morphometric studies further demonstrated that the cell body profile area (μm2) of nNOS-IR, ChAT-IR and CalR-IR neurons was increased by 34%, 20% and 55%, respectively, in the OG compared to controls Staining for NA H diaphorase activity is widely used to detect alterations in the enteric nervous system; however, our qualitative examination of NA H-diaphorase positive neurons in the myenteric ganglia revealed an overall similarity between the two groups CONCLUSION:We demonstrate increases in P2X2R expression and alterations in nNOS, ChAT and CalR IR in ileal myenteric neurons of female ob/ob mice compared to wild-type controls.
文摘Achillea millefolium (Asteraceae) is a permanent herb highly recognized in traditional medicine for its anti-oxidant and anti-inflammation properties. However, studies on phytochemical constituents of A. millefolium underlying these properties are scarce. The present work focuses on examining the effect of methanol extract of A. millefolium L. on total and differential blood cells account on albino male mice. The results showed the methanol extract increased the account of lymphocyte, and monocyte cells, and total account as well as this extract showed high decrease in the oxidative stress of MTX after the interfere between the extract and MTX due to increase in the leucocyte cells compared with controls. Concluded from these results that methanol extract of A. millefolium has ability enhancement in leucocyte cells in the blood and it has detoxification effect of MTX.
基金Supported by The Key Oncologic Subject Foundation of Hebei Province (No.200552),China
文摘The clinical characteristics of undifferentiated(embryonal) sarcoma of the liver(UESL) were investigated and the best treatment modalities were recommended.Both histology and immuno-histochemistry demonstrated the cellular features of this peculiar tumor.The tumor size was 12 cm × 9 cm × 8 cm in the right liver lobe.The patient underwent surgical resection of the tumor.The postoperative recovery was uneventful and she died eight months after diagnosis.The tumor showed mixed spindle and polygonal cells within the myxoid matrix.Some tumor cells contained eosinophilic hyaline globules that were positive for resistant diastase.Immunohistochemistry showed positive vimentin.Stellate and spindle cells were positively stained with alpha-1-antichymotrypsin(AACT) and CD68.This case indicates that UESL is not obviously differentiated in old-aged adults.
文摘Predicting the lifetime of polymeric insulators is one of the most important research topics in studying the life cycle of high voltage insulators in the power transmission and distribution networks. HTV (high temperature vulcanized) silicone rubber is a high performance dielectric material used within electrical power equipment, in particular transmission and distribution insulators. In this paper, we proposed a new approach using the Newton's method and Lagrange method to predict the aging of HTV silicone rubber that are subjected to multiple stress conditions. Concentration of chemical elements such as carbon, oxygen, silicon and aluminum were obtained and evaluated using a SEM (scanning electron microscope) with EDS (energy dispersive X-ray spectroscopy). Curve fitting using the Newton's and Lagrange interpolation methods yield useful linear interpolation equations that describe the aging characteristic of the specimens under study. This approach can be applied to predict the change in chemical concentration of polymeric insulators over the life cycle with good accuracy.