搭接长度等对Ⅱ型APC接头拉伸性能的影响

为研究搭接长度和钢筋直径对Ⅱ型APC接头力学性能的影响,对63个该接头进行单向拉伸试验,分析了接头破坏模式、极限承载力、延性和黏结应力等。结果表明:钢筋直径相同时,随搭接长度增加,平均黏结应力降低,试件强度、延性、最大力总伸长率明显提高,残余变形整体呈下降趋势;钢筋拉断破坏试件强度、延性、最大力总伸长率和残余变形满足规范要求;加载过程中,套筒中部截面短边纵向和长边环向始终受拉;极限荷载下,随搭接长度增加,套筒中部截面短边侧环向压应变先转变为拉应变再向压应变发展,长边侧纵向压应变转变为拉应变;相对搭接长度相同时,极限承载力随钢筋直径增加而提高;提出的极限黏结强度及临界搭接长度计算公式与试验值吻合较好,可为实际工程应用提供参考。单拉工况下,钢筋直径不大于18 mm时,建议接头搭接长度大于12 d。

Effects of thinning on the understory light environment of different stands and the photosynthetic performance and growth of the reforestation species Phoebe bournei

Light levels determine regeneration in stands and a key concern is how to regulate the light environment of different stand types to the requirements of the understory.In this study,we selected three stands typical in south China(a Cryptomeria japonica plantation,a Quercus acutissima plantation,and a mixed stand of both)and three thinning intensities to determine the best understory light environ-ment for 3-year-old Phoebe bournei seedlings.The canopy structure,understory light environment,and photosynthe-sis and growth indicators were assessed following thin-ning.Thinning improved canopy structure and understory light availability of each stand;species composition was the reason for differences in the understory light environ-ment.Under the same thinning intensity,the mixed stand had the greatest light radiation and most balanced spectral composition.P.bournei photosynthesis and growth were closely related to the light environment;all three stands required heavy thinning to create an effective and sustained understory light environment.In a suitable understory light environment,the efficiency of light interception,absorption,and use by seedlings was enhanced,resulting in a higher carbon assimilation the main limiting factor was stomatal conductance.As a shade-avoidance signal,red/far-red radia-tion is a critical factor driving changes in photosynthesis and growth of P.bournei seedlings,and a reduction increased light absorption and use capacity and height:diameter ratios.The growth advantage transformed from diameter to height,enabling seedlings to access more light.Our findings suggest that the regeneration of shade-tolerant species such as P.bournei could be enhanced if a targeted approach to thinning based on stand type was adopted.

Grain Yield,Biomass Accumulation,and Leaf Photosynthetic Characteristics of Rice under Combined Salinity-Drought Stress

Simultaneous stresses of salinity and drought often coincide during rice-growing seasons in saline lands,primarily due to insufficient water resources and inadequate irrigation facilities.Consequently,combined salinity-drought stress poses a major threat to rice production.In this study,two salinity levels(NS,non-salinity;HS,high salinity)along with three drought treatments(CC,control condition;DJ,drought stress imposed at jointing;DH,drought stress imposed at heading)were performed to investigate their combined influences on leaf photosynthetic characteristics,biomass accumulation,and rice yield formation.Salinity,drought,and their combination led to a shortened growth period from heading to maturity,resulting in a reduced overall growth duration.Grain yield was reduced under both salinity and drought stress,with a more substantial reduction under the combined salinity-drought stress.The combined stress imposed at heading caused greater yield losses in rice compared with the stress imposed at jointing.Additionally,the combined salinity-drought stress induced greater decreases in shoot biomass accumulation from heading to maturity,as well as in shoot biomass and nonstructural carbohydrate(NSC)content in the stem at heading and maturity.However,it increased the harvest index and NSC remobilization reserve.Salinity and drought reduced the leaf area index and SPAD value of flag leaves and weakened the leaf photosynthetic characteristics as indicated by lower photosynthetic rates,transpiration rates,and stomatal conductance.These reductions were more pronounced under the combined stress.Salinity,drought,and especially their combination,decreased the activities of ascorbate peroxidase,catalase,and superoxide dismutase,while increasing the contents of malondialdehyde,hydrogen peroxide,and superoxide radical.Our results indicated a more significant yield loss in rice when subjected to combined salinity-drought stress.The individual and combined stresses of salinity and drought diminished antioxidant enzyme activities,inhibited leaf photosynthetic functions,accelerated leaf senescence,and subsequently lowered assimilate accumulation and grain yield.

固定式下颌前移矫治器治疗青少年骨性Ⅱ类下颌后缩的临床效果

目的:观察固定式下颌前移矫治器治疗青少年骨性Ⅱ类下颌后缩的临床效果。方法:选取2023年3月—2024年8月在南昌大学附属口腔医院诊治的80例青少年骨性Ⅱ类下颌后缩患者,而后分组,指导原则为随机抽签法,具体组别为对照组、试验组,各组40例;其中,固定式下颌前移矫治器治疗方案用于试验组,对照组采用双颌垫矫正器,就青少年骨性Ⅱ类下颌后缩问题治疗效果展开比较。结果:两组治疗后SNA、ANB、U1-SN、L1-MP和Y轴角指标差异均无统计学意义(P>0.05),试验组SNB、MP-SN指标均比对照组大,差异均有统计学意义(P<0.05);治疗后,试验组L6-Ptm、L6-MP、CO-GO、GO-GN和ANS-Me指标均比对照组大,试验组U6-Ptm和U6-PP指标均比对照组小,差异均有统计学意义(P<0.05)。结论:在对青少年骨性Ⅱ类下颌后缩进行治疗时,将固定式下颌前移矫治器与双颌垫矫正器做比较,在部分角度及线性距离相关指标上,二者呈现出了不同的治疗效果,固定式下颌前移矫治器治疗效果优于双颌垫矫正器,这为临床治疗此类疾病提供了更多的参考依据,方便医生依据患者的具体情况选用更适宜的矫治器。

氨基酸功能化丝瓜络的辐射制备及其对Pb(Ⅱ)的吸附性能研究

以农林废弃物丝瓜络(LC)为基材,采用电子束辐射接枝法将聚甲基丙烯酸缩水甘油酯(PGMA)接枝到丝瓜络纤维表面,再通过开环反应引入赖氨酸(Lys)和精氨酸(Arg)功能性基团,制备得到2种氨基酸功能化丝瓜络LC-PGMA-Lys、LC-PGMA-Arg,通过FTIR、元素分析、XRD和SEM等方法对其进行了表征,系统研究了初始pH值、吸附时间、吸附温度、Pb(Ⅱ)初始浓度等因素对Pb(Ⅱ)吸附量的影响,并探究了其对Pb(Ⅱ)的吸附行为。结果表明,LC-PGMA-Lys、LC-PGMA-Arg吸附Pb(Ⅱ)的最佳初始pH值均为6;在初始pH值为6、吸附时间为200 min、吸附温度为35℃的最佳条件下,LC-PGMA-Lys对Pb(Ⅱ)的最大吸附量为71.18 mg·g^(-1);LC-PGMA-Lys对Pb(Ⅱ)的吸附过程符合准二级动力学方程和Freundlich等温吸附模型,表明吸附过程以多分子层吸附、化学吸附为主。

Photosynthetic response dynamics in the invasive species Tithonia diversifolia and two co-occurring native shrub species under fluctuating light conditions

To determine the invasiveness of invasive plants,many studies have compared photosynthetic traits or strategies between invasive and native species.However,few studies have compared the photosynthetic dynamics between invasive and native species during light fluctuations.We compared photosynthetic induction,relaxation dynamics and leaf traits between the invasive species,Tithonia diversifolia and two native species,Clerodendrum bungei and Blumea balsamifera,in full-sun and shady habitats.The photosynthetic dynamics and leaf traits differed among species.T.diversifolia showed a slower induction speed and stomatal opening response but had higher average intrinsic water-use efficiency than the two native species in full-sun habitats.Thus,the slow induction response may be attributed to the longer stomatal length in T.diversifolia.Habitat had a significant effect on photosynthetic dynamics in T.diversifolia and B.balsamifera but not in C.bungei.In shady habitat,T.diversifolia had a faster photosynthetic induction response than in full-sun habitat,leading to a higher average stomatal conductance during photosynthetic induction in T.diversifolia than in the two native species.In contrast,B.balsamifera had a larger stomatal length and slower photosynthetic induction and relaxation response in shady habitat than in full-sun habitat,resulting in higher carbon gain during photosynthetic relaxation.Nevertheless,in both habitats,T.diversifolia had an overall higher carbon gain during light fluctuations than the two native species.Our results indicated that T.diversifolia can adopt more effective response strategies under fluctuating light environments to maximize carbon gain,which may contribute to its successful invasion.

Effects of dense planting patterns on photosynthetic traits of different vertical layers and yield of wheat under different nitrogen rates

A two-year field experiment was conducted to measure the effects of densification methods on photosynthesis and yield of densely planted wheat.Inter-plant and inter-row distances were used to define ratefixed pattern(RR)and row-fixed pattern(RS)density treatments.Meanwhile,four nitrogen(N)rates(0,144,192,and 240 kg N ha-1,termed N0,N144,N192,and N240)were applied with three densities(225,292.5,and 360×10^(4)plants ha^(-1),termed D225,D292.5,and D360).The wheat canopy was clipped into three equal vertical layers(top,middle,and bottom layers),and their chlorophyll density(Ch D)and photosynthetically active radiation interception(FIPAR)were measured.Results showed that the response of Ch D and FIPAR to N rate,density,and pattern varied with different layers.N rate,density,and pattern had significant interaction effects on Ch D.The maximum values of whole-canopy Ch D in the two seasons appeared in N240 combined with D292.5 and D360 under RR,respectively.Across two growing seasons,FIPAR values of RR were higher than those of RS by 29.37%for the top layer and 5.68%for the middle layer,while lower than those of RS by 20.62%for the bottom layer on average.With a low N supply(N0),grain yield was not significantly affected by density for both patterns.At N240,increasing density significantly increased yield under RR,but D360 of RS significantly decreased yield by 3.72%and 9.00%versus D225 in two seasons,respectively.With an appropriate and sufficient N application,RR increased the yield of densely planted wheat more than RS.Additionally,the maximum yield in two seasons appeared in the combination of D360 with N144 or N192 rather than of D225 with N240 under both patterns,suggesting that dense planting combined with an appropriate N-reduction application is feasible to increase photosynthesis capacity and yield.

Effects of thinning and understory removal on water use efficiency of Pinus massoniana:evidence from photosynthetic capacity and stable carbon isotope analyses

Understanding the relationship between forest management and water use efficiency(WUE)is important for evaluating forest adaptability to climate change.However,the effects of thinning and understory removal on WUE and its key controlling processes are not well understood,which limits our comprehension of the physiological mechanisms of various management practices.In this study,four forest management measures(no thinning:NT;understory removal:UR;light thinning:LT;and heavy thinning:HT)were carried out in Pinus massoniana plantations in a subtropical region of China.Photosynthetic capacity and needle stable carbon isotope composition(δ^(13)C)were measured to assess instantaneous water use efficiency(WUE_(inst))and long-term water use efficiency(WUE_(i)).Multiple regression models and structural equation modelling(SEM)identified the effects of soil properties and physiological performances on WUE_(inst)and WUE_(i).The results show that WUE_(inst)values among the four treatments were insignificant.However,compared with the NT stand(35.8μmol·mol^(-1)),WUE_(i)values significantly increased to 41.7μmol·mol^(-1)in the UR,50.1μmol·mol^(-1)in the LT and 46.6μmol·mol^(-1)in HT treatments,largely explained by photosynthetic capacity and soil water content.Understory removal did not change physiological performance(needle water potential and photosynthetic capacity).Thinning increased the net photosynthetic rate(A_n)but not stomatal conductance(g_s)or predawn needle water potential(ψ_(pd)),implying that the improvement in water use efficiency for thinned stands was largely driven by radiation interception than by soil water availability.In general,thinning may be an appropriate management measure to promote P.massoniana WUE to cope with seasonal droughts under future extreme climates.

Exogenous calcium enhances the physiological status and photosynthetic capacity of rose under drought stress

Drought(water shortage)can substantially limit the yield and economic value of rose plants(Rosa spp.).Here,we characterized the effect of exogenous calcium(Ca^(2+))on the antioxidant system and photosynthesis-related properties of rose under polyethylene glycol 6000(PEG6000)-induced drought stress.Chlorophyll levels,as well as leaf and root biomass,were significantly reduced by drought;drought also had a major effect on the enzymatic antioxidant system and increased concentrations of reactive oxygen species.Application of exogenous Ca^(2+)increased the net photosynthetic rate and stomatal conductance of leaves,enhanced water-use efficiency,and increased the length and width of stomata following exposure to drought.Organ-specific physiological responses were observed under different concentrations of Ca^(2+).Application of 5 mmol·L^(-1)Ca^(2+)promoted photosynthesis and antioxidant activity in the leaves,and application of 10 mmol·L^(-1)Ca^(2+)promoted antioxidant activity in the roots.Application of exogenous Ca^(2+)greatly enhanced the phenotype and photosynthetic capacity of potted rose plants following exposure to drought stress.Overall,our findings indicate that the application of exogenous Ca^(2+)enhances the drought resistance of roses by promoting physiological adaptation and that it could be used to aid the cultivation of rose plants.

One-time application of controlled-release bulk blending fertilizer enhances yield,quality and photosynthetic efficiency in late japonica rice

Controlled-release urea(CRU)releases nitrogen(N)at the same pace that rice takes it up,which can effectively improve N use efficiency,increase rice yield and improve rice quality.However,few studies have described the effects of CRU application on the photosynthetic rate and endogenous enzyme activities of rice.Accordingly,a twoyear field trial was conducted with a total of seven treatments:CK,no N fertilizer;BBF,regular blended fertilizer;RBBF,20%N-reduced regular blended fertilizer;CRF1,70%CRU+30%regular urea one-time base application;CRF2,60%CRU+40%regular urea one-time base application;RCRF1,CRF1 treatment with 20%N reduction;and RCRF2,CRF2 treatment with 20%N reduction.Each treatment was conducted in triplicate.The results showed that the N recovery efficiency(NRE)of the controlled-release bulk blending fertilizer(CRBBF)treatments was significantly greater over the two years.There were significant yield increases of 4.1–5.9%under the CRF1treatment and 5.6–7.6%under the CRF2 treatment compared to the BBF treatment,but the differences between the reduced-N treatments RBBF and RCRF2 were not significant.Photosynthetic rates under the CRF1 and CRF2treatments were significantly higher than under the other treatments,and they had significantly greater RuBPCase,RuBisCO,glutamate synthase(GOGAT)and glutamine synthetase(GS)enzyme activities.Additionally,the soil NH_(4)^(+)-N and NO_(3)^(–)-N contents under the CRBBF treatments were significantly higher at the late growth stage of rice,which was more in-line with the fertilizer requirements of rice throughout the reproductive period.CRBBF also led to some improvement in rice quality.Compared with the BBF and RBBF treatments,the protein contents under the CRBBF treatments were reduced but the milling,appearance,eating and cooking qualities of the rice were improved.These results showed that the application of CRBBF can improve the NRE,photosynthetic rate and endogenous enzyme activities of rice,ensuring sufficient N nutrition and photosynthetic material production during rice growth and thereby achieving improved rice yield and quality.

The photosynthetic oxygen evolution does not exclude the important role and contribution of bicarbonate photolysis

Photosynthesis is the most important biochemical reaction on Earth. It has co-evolved and developed with the Earth, driving the biogeochemical cycle of all elements on the planet and serving as the only chemical process in nature that can convert light energy into chemical energy. Some heavy oxygen isotopic(^(18)O) labeling experiments have"conclusively" demonstrated that the oxygen released by photosynthesis comes only from water and are written into textbooks. However, it is not difficult to find that bicarbonate has never been excluded from the direct substrate of photosynthesis from beginning to end during the history of photosynthesis research. No convincing mechanism can be used to explain photosynthetic oxygen evolution solely from water photolysis. The bicarbonate effect, the Dole effect, the thermodynamic convenience of bicarbonate photolysis, the crystal structure characteristics of photosystem Ⅱ, and the reinterpretation of heavy oxygen isotopic labeling(^(18)O)experiments all indicate that the photosynthetic oxygen evolution does not exclude the important role and contribution of bicarbonate photolysis. The recently proposed view that bicarbonate photolysis is the premise of water photolysis, bicarbonate photolysis and water photolysis work together with a 1:1(mol/mol) stoichiometric relationship, and the stoichiometric relationship between oxygen and carbon dioxide released during photosynthetic oxygen evolution is also 1:1, has excellent applicability and objectivity, which can logically and reasonably explain the precise coordination between light and dark reactions during photosynthesis, the bicarbonate effect, the Dole effect, the Kok cycle and the neutrality of water and carbon in nature.This is of great significance for constructing the bionic artificial photosynthetic reactors and scientifically answering the question of the source of elemental stoichiometric relationships in nature.

血管紧张素Ⅱ对大鼠骨髓间充质干细胞棕色脂肪变的抑制作用

背景:骨髓间充质干细胞是脂肪细胞的来源之一,且表达所有肾素血管紧张素系统成分,但血清血管紧张素Ⅱ对骨髓间充质干细胞向棕色脂肪组织分化的影响尚不清楚。目的:观察血管紧张素Ⅱ对骨髓间充质干细胞向棕色脂肪细胞分化的影响,并探究血管紧张素1a型受体敲除对血管紧张素Ⅱ影响骨髓间充质干细胞向棕色脂肪细胞分化的作用及可能机制。方法:分离培养野生型SD大鼠及血管紧张素1a型受体敲除SD大鼠的骨髓间充质干细胞,将其培养至第3代,随机分为4组:野生组,基因敲除组,野生+血管紧张素Ⅱ组,基因敲除+血管紧张素Ⅱ组,在棕色脂肪诱导分化培养基中诱导分化14 d,后2组在每次更换分化培养基的同时加入100 nmol/L血管紧张素Ⅱ进行干预。采用Western blot、qRT-PCR、免疫荧光等方法检测棕色脂肪诱导分化、脂肪分解、β氧化和线粒体生物发生等相关标记物的表达。结果与结论:血管紧张素Ⅱ可抑制骨髓间充质干细胞向棕色脂肪细胞分化,敲除血管紧张素1a型受体基因能够通过促进脂肪分解、增强脂肪酸β氧化、促进线粒体生物发生、增强线粒体功能来改善血管紧张素Ⅱ对骨髓间充质干细胞向棕色脂肪细胞分化的抑制作用。这些发现为肥胖治疗提供了新的研究方向和潜在治疗靶点,揭示了肾素血管紧张素系统在脂肪代谢中的重要作用及其作为治疗目标的潜力。

Effect of Various Citrus Rootstock-scion Combinations on Tree Growth,Fruit Quality,and Photosynthetic Characteristics under Red Loam Soil Conditions

[Objectives]To investigate the effects of 15 distinct citrus rootstock-scion combinations on tree growth,fruit quality,and photosynthetic characteristics under red loam soil conditions and provide a theoretical foundation for the selection of appropriate citrus rootstock-scion combinations in the Zhaoqing region.[Methods]A total of 15 citrus rootstock-scion combinations were utilized as test materials for a comprehensive analysis of their phenological periods(budding,flowering,and fruiting),tree growth indicators(tree height,crown diameter,and growth),and fruit quality(appearance quality and intrinsic quality).The photosynthetic characteristics of the test materials,including the net photosynthetic rate(Pn),transpiration rate(Tr),water use efficiency(WUE),apparent quantum yield(AQY),and carboxylation efficiency(CE),were analyzed to determine their significance.Additionally,the leaf photosynthetic physiological indicators,such as soluble protein,specific leaf weight,chlorophyll,and carotenoids,were evaluated.[Results]There were notable differences observed in the phenological period,growth potential of trees,fruit quality,and photosynthetic characteristics among various citrus rootstock-scion combinations.The phenological periods exhibited variation contingent on the grafting varieties.In terms of tree growth potential,the Citrus tangerina Tanaka‘Hongju’and C.haniana Hort.‘Suanju’rootstocks demonstrated greater tree height,crown growth,and overall tree strength;however,they were also prone to excessive growth.Conversely,the C.limonia Osbeck‘Hongningmeng’and C.sinensis×P.trifoliata‘Zhicheng’rootstocks displayed medium growth potential,while the Poncirus trifoliate(L)Raf.‘Zhike’rootstock resulted in shorter trees.In terms of fruit quality,the single fruit weight of C.flamea Hort.‘Shatangju’ranged from 33 to 50 g,exhibiting a flat and round shape.The total soluble solids and titratable acid content of‘Shatangju’grafted onto the‘Zhike’rootstock were notably high.In contrast,the single fruit weight of C.haniana Hort.‘Chuntianju’varied between 65 and 81 g,characterized by a high flat round shape.The‘Suanju’rootstock demonstrated a higher sugar and acid content compared to other rootstocks.Additionally,the single fruit weight of C.nobilis Lour.‘Gonggan’ranged from 62 to 145 g,with the fruit shape being either round or oval.The soluble sugar and total soluble solids content associated with the‘Zhike’rootstock was also elevated.In relation to photosynthetic characteristics,the photosynthetic performance of the‘Shatangju’variety was superior when grafted onto the‘Zhike’and‘Hongju’rootstocks.Similarly,the‘Chuntianju’variety exhibited enhanced photosynthetic performance on the‘Zhike’,‘Zhicheng’,and‘Hongju’rootstocks.Furthermore,the‘Gonggan’variety demonstrated improved photosynthetic performance when grafted onto the‘Zhike’and‘Suanju’rootstocks.[Conclusions]Based on the characteristics of the red loam soil in the Zhaoqing region,the rootstocks‘Zhike’and‘Hongju’are conducive to the cultivation of the‘Shatangju’variety.Additionally,the rootstocks‘Zhike’,‘Zhicheng’,and‘Hongju’are optimal for the growth of the‘Chuntianju’variety,while the rootstocks‘Zhike’and‘Suanju’are appropriate for the growth of the‘Gonggan’variety.

μNGAL、Ccr、降钙素原联合APACHEⅡ评分对脓毒症相关急性肾损伤预后的预测价值

目的探讨尿中性粒细胞明胶酶相关脂质运载蛋白(μNGAL)、内生肌酐清除率(Ccr)、降钙素原联合急性生理学与慢性健康状况评分系统Ⅱ(APACHEⅡ)对脓毒症相关急性肾损伤(SA-AKI)患者生存预后的预测价值。方法回顾性分析2019年7月至2024年6月收治的120例SA-AKI患者,根据28 d生存状态将患者分为生存组79例和死亡组41例,采用多因素logistic分析影响患者生存的因素,并绘制受试者工作特征(ROC)曲线分析μNGAL、Ccr、降钙素原联合APACHEⅡ评分预测SA-AKI患者预后的价值。结果120例SA-AKI患者28 d内病死率为34.17%(41/120)。μNGAL、降钙素原、超敏C反应蛋白、血肌酐水平和APACHEⅡ评分是SA-AKI患者死亡的独立危险因素,Ccr和血清白蛋白水平是患者死亡的保护因素(P<0.05,P<0.01)。μNGAL、APACHEⅡ评分、Ccr、降钙素原水平联合预测患者死亡的曲线下面积大于单独指标预测。结论μNGAL、降钙素原、Ccr水平和APACHEⅡ评分对SA-AKI患者生存预后有一定的预测能力,且联合预测价值最高。

Post Cryopreservation Growth Kinetic and Photosynthetic Assessment of an Acid Tolerant Strain of Stichococcus bacillaris

Preserving microbial diversity has become a strategic undertaking. Thus, ex situ microalgal culture conservation results in strategic and functional resource in both biodiversity protection and application domains. Cryopreservation of microalgae has been practiced since the 1960s and is now considered the optimal preservation strategy. Furthermore, the overall monitoring during growth of cultures after freezing/thawing protocols was hardly investigated and there is poor evaluation related to preserve especially the photosystem apparatus. The present study focuses on Stichococcus bacillaris as case study for short-term cryopreservation at −80 °C storage. Various freezing pretreatments using cryoprotective agents, and two thawing methods were compared introducing a novel variable to evaluate viability recovery and assessing growth kinetics of cultures immediately after thawing and after a series batch cultivation. Photosynthetic rate and pigments assessment were proposed to evaluate hidden metabolic cell damage. Results underline cryoprotective agents can increase the kinetic recovery of preserved cells in terms of reduction of lag phase during batch cultivation tests: the use of dimethyl sulfoxide and glycerol granted a growth comparable to unpreserved cells when sudden thawing occurs after 24 hours of storage, but recovery after preservation is less sensitive to cryoprotective agents when gradual thawing and 1 month of storage is considered. However, cells are always able to restore their physiological pathways even without agents, so their kinetic effect has been proved and quantified. Interestingly, both the photosynthetic efficiency and the ratio between total chlorophyll and carotenoids are comparable (0.75 Fv/Fm, 2.2 ± 0.25 g/g) to unpreserved cells and they are unsensitive to chosen agents, but the ratio between chlorophyll a and chlorophyll b was clearly altered (up to 10 times), suggesting that photoactive pigments relative proportions can result in similar growth kinetic performances. Long-term studies will be carried out to assess whether the differences found could cause chronic damage to photosystem efficiency of S. bacillaris cultures.

基于NSGA-Ⅱ+ARSBX算法的太原市水资源优化配置

为优化太原市水资源配置,设置考虑节水意识和非常规水的供需预测情景,采用NSGA-Ⅱ+ARSBX算法求解水资源优化配置模型,并构建多系统耦合协调度评价模型评价该算法的求解能力。基于供需预测结果,根据不同保证率下的可供水量选择合适的节水意识情景,配置结果中非常规水量平均占比26.08%,供水比例仅低于外调水(35.77%);不同水平年不同保证率下NSGA-Ⅱ+ARSBX算法的协调度均大于0.8,优于NSGA-Ⅱ算法。结果表明:保证率75%、95%时需要中节水意识甚至高节水意识才能改善缺水情况,且非常规水占总供水量比例超过1/4,将其纳入供水系统对缓解太原市水资源紧张起到了重要作用;与NSGA-Ⅱ算法相比,NSGA-Ⅱ+ARSBX算法在水资源优化配置中具有更好的可行性,能够为水资源优化配置模型求解提供新途径。

大麻素Ⅱ型受体在股骨头坏死中的研究进展

大麻素Ⅱ型受体(CB2R)是内源性大麻素系统的重要组成部分,因其具有镇痛、抗炎、抗癫痫、抗纤维化及调节骨代谢等作用,已被广泛应用于临床及研究。近年来利用CB2R治疗多种疑难疾病已成为研究热点,尤其是对于骨科疾病的治疗。目前针对早中期股骨头坏死(ONFH)患者尚无疗效确切的方法,由于CB2具有抗炎、缓解疼痛、促进BMSCs成骨分化以及维持骨重塑稳态等作用,因此对其展开研究,希望CB2R能成为治疗ONFH的有效靶点。

基于混合NSGA-Ⅱ算法的机场车辆调度研究

针对机场保障车辆资源调度问题,现有的人工调度方式存在时间成本较高、资源运行效率较低的问题,该研究探索了一种混合NSGA-Ⅱ算法。该算法结合了邻域搜索和NSGA-Ⅱ算法,旨在实现任务数量均衡性和最小车辆行驶距离这两个目标,以求解车辆调度模型。通过对国内某机场实际航班数据进行仿真实验,结果表明,该研究所提出的算法模型能够有效解决机场保障车辆的调度问题。

血管紧张素Ⅱ微量泵植入和皮下注射致小鼠心肌纤维化的造模方法比较

目的:比较血管紧张素Ⅱ(AngⅡ)微量泵植入和皮下注射两种造模方式及不同剂量致小鼠心肌纤维化的成模情况及成模差异性,确定较优的动物模型复制方法。方法:40只雄性C57BL/6小鼠随机分为空白对照组、微量泵组[微量泵皮下植入1.5 mg/(kg·d)]、皮下组1[皮下注射1.5 mg/(kg·d)]和皮下组2[皮下注射2.5 mg/(kg·d)],每组10只,空白组不做任何处理,其余组给予AngⅡ,持续28 d,观察小鼠一般状态。第28天行心电图和超声心动图检测心功能,HE、Masson染色观察心脏病理变化,ELISA检测血清脑钠肽(BNP)水平,Western blot检测心肌α-平滑肌肌动蛋白(α-SMA)、Ⅰ型胶原蛋白(CollagenⅠ)、Ⅲ型胶原蛋白(CollagenⅢ)蛋白表达。结果:同空白对照组比较,各给药组小鼠一般状态、心电图受影响程度为微量泵组>皮下组2>皮下组1。超声心动图微量泵组和皮下组2的左室射血分数(EF)、左室短轴缩短率(FS)下降(均P<0.05),左室舒张末期内径(LVIDd)、左室收缩末期内径(LVIDs)、左室舒张末期容量(LVEDV)、左室收缩末期容量(LVESV)、左室质量(LVd Mass)均上升(均P<0.05);皮下组1的FS下降(P<0.05),LVIDs、LVIDd上升(均P<0.05),各组间EF比较有统计学差异(均P<0.05)。微量泵组和皮下组2的BNP均显著升高(P<0.05),皮下组1与空白对照组比较无统计学差异,各给药组间比较差异有统计学意义(P<0.05)。HE染色微量泵组炎性细胞浸润明显大于皮下组,Masson染色胶原纤维沉积高于皮下组2(均P<0.05),皮下组1与空白对照组比较无统计学差异(P>0.05)。Western blot微量泵组和皮下组2的α-SMA、CollagenⅠ、CollagenⅢ蛋白表达显著增高(均P<0.05),皮下组1仅α-SMA增高(P<0.05)。结论:微量泵1.5 mg/(kg·d)和皮下注射2.5 mg/(kg·d)累积28 d均可建立心肌纤维化模型,微量泵组明显优于皮下注射;皮下注射1.5 mg/(kg·d)诱导心肌纤维化不明显。

基于NSGAⅡ-RF的样本不平衡下设备故障诊断

在智能制造产业的设备缺陷与故障诊断中,欠采样容易丢失重要的样本信息,而过采样容易引入冗杂信息。针对这些问题,将带精英策略的非支配排序遗传算法(non-dominated sorting genetic algorithm Ⅱ,NSGAⅡ)融入随机森林(random forest,RF)算法中,用多目标遗传算法代替传统RF算法中的自助采样法和特征选取方法,产生多样化的、性能优良的特征子集和样本子集,从而生成多样性强、准确性高的决策树,同时确定最优的决策树数量,达到优化RF算法的性能并提高分类精度的目的。基于多类别和高度不平衡的设备故障数据集进行故障诊断实验,并将所提算法与结合了合成少数类过采样技术(synthetic minority oversampling technique,SMOTE)的集成学习算法等进行比较,实验结果表明,所提算法的故障诊断准确率优于对比算法。