To achieve low-carbon regulation of electric vehicle(EV)charging loads under the“dual carbon”goals,this paper proposes a coordinated scheduling strategy that integrates dynamic carbon factor prediction and multiobje...To achieve low-carbon regulation of electric vehicle(EV)charging loads under the“dual carbon”goals,this paper proposes a coordinated scheduling strategy that integrates dynamic carbon factor prediction and multiobjective optimization.First,a dual-convolution enhanced improved Crossformer prediction model is constructed,which employs parallel 1×1 global and 3×3 local convolutionmodules(Integrated Convolution Block,ICB)formultiscale feature extraction,combinedwith anAdaptive Spectral Block(ASB)to enhance time-series fluctuationmodeling.Based on high-precision predictions,a carbon-electricity cost joint optimization model is further designed to balance economic,environmental,and grid-friendly objectives.The model’s superiority was validated through a case study using real-world data from a renewable-heavy grid.Simulation results show that the proposed multi-objective strategy demonstrated a superior balance compared to baseline and benchmark models,achieving a 15.8%reduction in carbon emissions and a 5.2%reduction in economic costs,while still providing a substantial 22.2%reduction in the peak-valley difference.Its balanced performance significantly outperformed both a single-objective strategy and a state-of-the-art Model Predictive Control(MPC)benchmark,highlighting the advantage of a global optimization approach.This study provides theoretical and technical pathways for dynamic carbon factor-driven EV charging optimization.展开更多
AIM： To investigate the protective effect and mechanism of alanyl-glutamine dipeptide （Ala-GIn） against hepatic ischemia-reperfusion injury in rats. METHODS： Rats were divided into group C as normal control Group ...AIM： To investigate the protective effect and mechanism of alanyl-glutamine dipeptide （Ala-GIn） against hepatic ischemia-reperfusion injury in rats. METHODS： Rats were divided into group C as normal control Group （/7=16） and group G as alanyl-glutamine pretreatment 07=16）. Rats were intravenously infused with 0.9% saline solution in group C and Ala-GIn -enriched （2% glutamine） 0.9% saline solution in group G via central venous catheter for three days. Then all rats underwent hepatic warm ischemia for 30 min followed by different periods of reperfusion. Changes in biochemical parameters, the content of glutathione （GSH） and the activity of superoxide dismutase （SOD） in liver tissue, Bcl-2 and Bax protein expression and morphological changes of liver tissue were compared between both groups. RESULTS： One hour after reperfusion, the levels of liver enzymes in group G were significantly lower than those in group C （P〈0.05）. Twenty-four hours after reperfusion, the levels of liver enzymes in both groups were markedly recovered and the levels of liver enzyme in group G were also significantly lower than those in group C （P〈0.01）. One and 24 h after reperfusion, GSH content in group G was significantly higher than that in group C （P 〈0.05）. There was no statistical difference in activities of SOD between the two groups. One and 24 h after reperfusion, the positive expression rate of Bcl-2 protein was higher in group G than in group C （P〈0.05） and the positive expression rate of Bax protein was lower in group G than in group C （P〈0.05）. Histological and ultrastructural changes of liver tissue were inhibited in group C compared to group G. CONCLUSION： Our results suggest that Ala-GIn pretreatment provides the rat liver with significant tolerance to warm ischemia-reperfusion injury, which may be mediated partially by enhancing GSH content and regulating the expression of Bcl-2 and Bax proteins in the liver tissue.展开更多
The aim of this study was to investigate the mechanism by which a diet inducing high hyperhomocysteinemia(HHcy)leads to the deterioration of erectile function in rats and whether this is inhibited by expression of the...The aim of this study was to investigate the mechanism by which a diet inducing high hyperhomocysteinemia(HHcy)leads to the deterioration of erectile function in rats and whether this is inhibited by expression of the human tissue kallikrein-1(hKLKl)gene.We established a rat model of HHcy by feeding methionine(Met)-rich diets to male Sprague-Dawley(SD)rats.Male wild-type SD rats(WTRs)and transgenic rats harboring the hKLKl gene(TGRs)were fed a normal diet until 10 weeks of age.Then,30 WTRs were randomly divided into three groups as follows:the control(n=10)group,the low-dose(4%Met,n=10)group,and the high-dose(7%Met,n=10)group.Another 10 age-matched TGRs were fed the high-dose diet and designated as the TGR+7%Met group.After 30 days,in all four groups,erectile function was measured and penile tissues were harvested to determine oxidative stress,endothelial cell content,and penis fibrosis.Compared with the 7%Met group,the TGR+7%Met group showed diminished HHcy-induced erectile dysfunction(ED),indicating the improvement caused by hKLKl.Regarding corpus cavernosum endothelial cells,hKLKl preserved endothelial cell-cell junctions and endothelial cell content,and activated protein kinase B/endothelial nitric oxide synthase(Akt/eNOS)signaling.Fibrosis assessment indicated that hKLKl preserved normal penis structure by inhibiting apoptosis in the corpus cavernosum smooth muscle cells.Taken together,these findings showed that oxidative stress,impaired corpus cavernosum endothelial cells,and severe penis fibrosis were involved in the in duction of ED by HHcy in rats,whereas hKLKl preserved erectile function by inhibiting these pathophysiological changes.展开更多
A method based on the computational fluid dynamics （CFD） is presented for a flexible waverider＇s design. The generating bodies of this method could be any cones. In addition, either the leading edge or the profile ...A method based on the computational fluid dynamics （CFD） is presented for a flexible waverider＇s design. The generating bodies of this method could be any cones. In addition, either the leading edge or the profile of the scramjet＇s inlet is used as the waverider＇s definition curve, parameterized by the quadric function, the sigmoid function or the B-spline function. Furthermore, several numerical examples are carried out to validate the method and the relevant codes. The CFD results of the configurations show that all the designs are successful. Moreover, primary suggestions are proposed for practical design by comparing the geometrical and aerodynamic performances of the conederived waveriders at Mach 6.展开更多
Bridgman directional solidification of investment castings is a key technology for the production of reliable and highly efficient gas turbine blades. In this paper, a mathematical model for three-dimensional （3D） s...Bridgman directional solidification of investment castings is a key technology for the production of reliable and highly efficient gas turbine blades. In this paper, a mathematical model for three-dimensional （3D） simulation of solidification process of single crystal investment castings was developed based on basic heat transfer equations. Complex heat radiation among the multiple blade castings and the furnace wall was considered in the model. Temperature distribution and temperature gradient in superalloy investment castings of single blade and multiple ones were investigated, respectively. The calculated cooling curves were compared with the experimental results and agreed well with the latter. It is indicated that the unsymmetrical temperature distribution and curved liquid-solid interface caused by the circle distribution of multiple turbine blades are probably main reasons why the stray grain and other casting defects occur in the turbine blade.展开更多
Previous studies have shown that oxidative stress and corporal fibrosis in penile tissues of rats were key pathological factors of erectile dysfunction induced by diabetic mellitus （DMED）. Lipoxin A4 （LXA4） was re...Previous studies have shown that oxidative stress and corporal fibrosis in penile tissues of rats were key pathological factors of erectile dysfunction induced by diabetic mellitus （DMED）. Lipoxin A4 （LXA4） was reported to inhibit oxidative stress and fibrosis diseases, while whether it could exert a protective role on erectile function was not clear. Type I diabetic mellitus （DM） was induced in thirty male lO-week-old Sprague-Dawley rats using streptozotocin. Ten weeks later, twenty-two rats with DMED confirmed by an apomorphine test were divided into two groups： the DMED group （n = 11） and the DMED ＋ LXA4 group （n = 11; LXA4 injection daily for 4 weeks）. In addition, another ten age-matched rats formed the Control group. We found that erectile function was significantly impaired in the DMED group compared with the Control group, but was improved in the DMED ＋ LXA4 group. Similarly, the over-activated oxidative stress and impaired endothelial function in the DMED group were both improved in the DMED ＋ LXA4 group. Moreover, the DMED group showed serious corporal fibrosis, which was also inhibited by the treatment of LXA4 in the DMED ＋ LXA4 group. Taken together, LXA4 could exert an inhibition role on oxidative stress and fibrosis to improve DMED effectively.展开更多
Our previous studies have demonstrated that erectile function was preserved in aged transgenic rats （TGR） harboring the human tissue kallikrein 1 （hKLK1）, while the molecular level of hKLK1 on corporal fibrosis to...Our previous studies have demonstrated that erectile function was preserved in aged transgenic rats （TGR） harboring the human tissue kallikrein 1 （hKLK1）, while the molecular level of hKLK1 on corporal fibrosis to inhibit age-related erectile dysfunction （ED） is poorly understood. Male wild-type Sprague-Dawley rats （WTR） and TGR harboring the hKLK1 gene were fed to 4- or 18-month-old and divided into three groups： young WTR （yWTR） as the control, aged WTR （aWTR）, and aged TGR （aTGR）. Erectile function of all rats was assessed by cavernous nerve electrostimulation method. Masson＇s trichrome staining was used to evaluate corporal fibrosis in the corpus cavernosum. We found that the erectile function of rats in the aWTR group was significantly lower than that of other two groups. Masson＇s trichrome staining revealed that compared with those of the yWTR and aTGR groups, the ratio of smooth muscle cell （SMC）/collagen （C） was significantly lower in the aWTR group. Immunohistochemistry and Western blotting analysis were performed, and results demonstrated that expression of a-SMA was lower, while expressions of transforming growth factor-β1 （TGF-β1）, RhoA, ROCK1, p-MYPT1, p-LIMK2, and p-cofilin were higher in the aWTR group compared with those in other two groups. However, LIMK2 and cofilin expressions did not differ among three groups. Taken together, these results indicated that the RhoA/ROCK1/LIMK/cofilin pathway may be involved in the corporal fibrosis caused by advanced age, and hKLK1 may reduce this corporal fibrosis by inhibiting the activation of this pathway to ameliorate age-related ED.展开更多
Background: Black bone sheep was first discovered in Yunnan province of China in 1970, with unique black pigmentation on the body and internal organs. Endothelin 3(EDN3) has been known as a key gene causing hyperpigme...Background: Black bone sheep was first discovered in Yunnan province of China in 1970, with unique black pigmentation on the body and internal organs. Endothelin 3(EDN3) has been known as a key gene causing hyperpigmentation in black bone chicken, the Silky fowl.Methods: In this study, EDN3 was employed as a candidate gene for regulating black color pigmentation. First,EDN3 was cloned from sheep to obtain the full-length cDNA by using the rapid amplification of cDNA ends(RACE).Genomic EDN3 was screened and a total of thirty predicted single nucleotide polymorphisms(SNPs) were genotyped for allele and genotype frequency analysis in a case-control study involving two black bone sheep populations. Genomic copy number analysis of EDN3 in sheep was conducted to measure the variation in copy number. EDN3 expression levels were observed among the groups in adult liver, lymph node, and kidney tissues, as well as embryo kidney samples. Also, among the tissues of black bone and non-black bone sheep.Results: The size of the full-length cDNA was 1,578 bp, which included 426 bp of 5′-untranslated region(5′-UTR),an open reading frame(ORF) of 639 bp encoding a protein of 212 amino acids, and a 3′-UTR of 513 bp. Genotype and allele frequencies of all the discovered SNPs were found insignificantly different in black bone and non-black bone sheep(P > 0.05). Genomic copy number analysis of EDN3 in sheep revealed no significant difference between the two sheep groups. No significant variations were found in the adult liver and kidney embryo samples. However,the expression in lymph node and kidney tissue was significantly higher in black bone sheep than that in non-black bone sheep(P < 0.05). Significant variations in the EDN3 expression levels were observed among the tissues of nonblack bone sheep.Conclusions: The findings of the present study indicate that unlike in Silky chickens, EDN3 is not responsible for hyperpigmentation but may play a key functional role in immune and excretory systems of black bone sheep.展开更多
Concrete-plate fences have been widely adopted for windblown sand control and mitigation along railways.However,the inclination angles of inserting the concrete plate with respect to the vertical direction,i.e.,straig...Concrete-plate fences have been widely adopted for windblown sand control and mitigation along railways.However,the inclination angles of inserting the concrete plate with respect to the vertical direction,i.e.,straight or obliquely inserted concrete plates(SIP or OIP),significantly influence the efficiency of sand-control.This study performs a comparative evaluation of the SIP and OIP sand-control fences using wind tunnel testing and field monitoring data collected from the Lanzhou–Wulumuqi High-Speed Railway Project.The results show that the fence’s ability to reduce the wind speed and the sand-retaining efficiency gradually weakens with the increasing wind speed.Compared with the SIP fence,the OIP fence has a better wind speed reduction capability,stronger ability to capture fine particles below the top of the fence;it is more efficient for sand-retaining and induces stronger eddy intensity.Generally,the wind tunnel test and field monitoring results are consistent,whereas wind tunnel tests incline to overestimate wind speed reduction and sand-control efficiency.The study also finds that the aeolian sand accumulated around the fence can weaken the protection efficiency,and hence cleaning the aeolian sand accumulated around the fence should be done periodically to ensure the designed functions.展开更多
AIM:To find potential mutable sites by detecting mutations of the candidate gene in a kindred with polycystic liver disease(PCLD).METHODS:First,we chose a kindred with PCLD and obtained five venous blood samples of th...AIM:To find potential mutable sites by detecting mutations of the candidate gene in a kindred with polycystic liver disease(PCLD).METHODS:First,we chose a kindred with PCLD and obtained five venous blood samples of this kindred after the family members signed the informed consent form.In the kindred two cases were diagnosed with PCLD,and the left three cases were normal individuals.All the blood samples were preserved at-85?℃.Second,we extracted the genomic DNA from the venous blood samples of the kindred using a QIAamp DNA Mini Kit and then performed long-range polymerase chain reaction(PCR)with different primers.The exons of PKD1 were all sequenced with the forward and reverse primers to ensure the accuracy of the results.Next,we purified the PCR products and directly sequenced them using Big Dye Terminator Chemistry version 3.1.The sequencing reaction was conducted with Biomek FX(Beckman).Finally,we analyzed the results.RESULTS:A total of 42 normal exons were identified in detecting mutations of the PKD1 gene.A synonymous mutation occurred in exon 5.The mutation was a homozygous T in the proband and was C in the reference sequence.This mutation was located in the third codon and did not change the amino acid encoded by the codon.Missense mutations occurred in exons 11 and 35.These mutations were located in the second codon;they changed the amino acid sequence and existed in the db SNP library.A nonsense mutation occurred in exon 15.The mutation was a heterozygous CT in the proband and was C in the referencesequence.This mutation was located in the first codon and resulted in a termination codon.This mutation had an obvious influence on the encoded protein and changed the length of the protein from 4303 to 2246amino acids.This was a new mutation that was not present in the db SNP library.CONCLUSION:The nonsense mutation of exon 15existed in the proband and in the third individual.Additionally,the proband was heterozygous for this mutation,so the mutable site was a pathogenic mutation.展开更多
Focused exploration of earth-abundant and cost-efficient non-noble metal electrocatalysts with superior hydrogen evolution reaction(HER)performance is very important for large-scale and efficient electrolysis of water...Focused exploration of earth-abundant and cost-efficient non-noble metal electrocatalysts with superior hydrogen evolution reaction(HER)performance is very important for large-scale and efficient electrolysis of water.Herein,a sandwich composite structure(designed as MS-Mo2C@NCNS)ofβ-Mo2C hollow nanotubes(HNT)and N-doped carbon nanosheets(NCNS)is designed and prepared using a binary NaCl–KCl molten salt(MS)strategy for HER.The temperature-dominant Kirkendall formation mechanism is tentatively proposed for such a three-dimensional hierarchical framework.Due to its attractive structure and componential synergism,MS-Mo2C@NCNS exposes more effective active sites,confers robust structural stability,and shows significant electrocatalytic activity/stability in HER,with a current density of 10 mA cm-2 and an overpotential of only 98 mV in 1 M KOH.Density functional theory calculations point to the synergistic effect of Mo2C HNT and NCNS,leading to enhanced electronic transport and suitable adsorption free energies of H*(ΔGH*)on the surface of electroactive Mo2C.More significantly,the MS-assisted synthetic methodology here provides an enormous perspective for the commercial development of highly active non-noble metal electrocatalysts toward efficient hydrogen evolution.展开更多
The microstructure and microhardness of directionally solidified NiAl-W eutectic alloys at growth rates of 2-25μm·s^-1 were investigated by a Bridgman crystal growing facility at a temperature gradient of 300 K&...The microstructure and microhardness of directionally solidified NiAl-W eutectic alloys at growth rates of 2-25μm·s^-1 were investigated by a Bridgman crystal growing facility at a temperature gradient of 300 K·cm^-1.In view of the competitive growth between W dendritic and eutectic phases,W dendritic phase was eliminated,whereas the fully eutectic phase was prominent in the steady progress of the directionally solidified NiAl-W eutectic alloys.As the growth rate(V)increased,both the structure and solid/liquid interface of the directionally solidified NiAl-W eutectic alloys changed from planar to cellular.Both the fibrous spacing(d)and the diameter(a)decreased with increase in growth rate(V).The Vickers microhardness(H)of the directionally solidified NiAl-W eutectic alloys decreased with fibrous spacing(d)or diameter(a)increasing.The relationships of H to d and a were H=371.58 d^(-0.09)and H=297.70 a^(-0.09),respectively.展开更多
Lead halide perovskites MAPbX_(3)(MA = CH_(3)NH_(3) or Cs;X = I, Br, Cl) are well considered to be potential candidates for photocatalytic reaction due to its excellent photoelectrical properties, but they still suffe...Lead halide perovskites MAPbX_(3)(MA = CH_(3)NH_(3) or Cs;X = I, Br, Cl) are well considered to be potential candidates for photocatalytic reaction due to its excellent photoelectrical properties, but they still suffer from the low charge separation efficiency and slow catalytic reaction dynamics. To tackle the drawbacks, herein, MAPbBr_(3)/carbon sphere(CS) composite photocatalysts using glucose as the carbon source were elaborately designed and fabricated via a dry mechanochemical grinding process. The interfacial interaction Pb-O-C chemical bonds were constructed between MAPbBr_(3) and the carbon sphere surface containing organic functional groups. By optimizing the content of CSs, the enhanced photocatalytic degradation kinetic rate of Malachite Green(MG) pollutants(92% within 20 min) for MAPbBr_(3)/CS x( x = 17 wt.%) is about 3.6-fold of that for pristine MAPbBr_(3), which is attributed to the corporative adsorption and enhanced carrier transportation and separation of MAPbBr_(3)/CS x. Furthermore, the possible degradation mechanism was proposed on basis of the electrochemical, mass spectrometry and optical characterization results. Owing to the robust interfacial interaction, effective electron extraction rate( k et = 4.6 × 10^(7) sec^(-1)) from MAPbBr_(3) to CS can be established, which driven oxygen activation where superoxide radicals(·O^(2-)) played an important role in MG degradation. It is expected that mechanochemistry strategy may provide a new route to design efficient lead halide perovskite-carbon or metal oxide or sulfide composite photocatalysts.展开更多
A hybrid approach based on the immersed boundary method(IBM)is developed for computation of flow-induced sound around moving bodies.In this method,a high-fidelity direct numerical simulation(DNS)solver is used to simu...A hybrid approach based on the immersed boundary method(IBM)is developed for computation of flow-induced sound around moving bodies.In this method,a high-fidelity direct numerical simulation(DNS)solver is used to simulate the incompressible flow field.The sound field is predicted by discretizing acoustic perturbation equations(APEs)with dispersionrelation-preserving space scheme and low-dispersion and low-dissipation Runge-Kutta time integration.A sharp-interface IBM based on ghost-cell is implemented for present two-step DNS-APE approach to deal with complex moving bodies with Cartesian grids.The present method is validated through simulations of sound generation caused by flow past a rotating cylinder,an oscillating cylinder,and tandem oscillating and stationary cylinders.The sound generated by typical kinds of complicated bio-inspired locomotions,i.e.,flapping flight by wings of varied shapes and collective undulatory swimming in tandem,are investigated using present method.The results demonstrate potential of the hybrid approach in addressing flowinduced sound generation and propagation with complex moving boundaries in a fluid medium,especially for the sound characteristics of bio-mimetic flows,which might shed lights on investigations on bio-acoustics,ethology of complex animal system,and related bio-mimetic design for quietness.展开更多
基金Supported by State Grid Corporation of China Science and Technology Project:Research on Key Technologies for Intelligent Carbon Metrology in Vehicle-to-Grid Interaction(Project Number:B3018524000Q).
文摘To achieve low-carbon regulation of electric vehicle(EV)charging loads under the“dual carbon”goals,this paper proposes a coordinated scheduling strategy that integrates dynamic carbon factor prediction and multiobjective optimization.First,a dual-convolution enhanced improved Crossformer prediction model is constructed,which employs parallel 1×1 global and 3×3 local convolutionmodules(Integrated Convolution Block,ICB)formultiscale feature extraction,combinedwith anAdaptive Spectral Block(ASB)to enhance time-series fluctuationmodeling.Based on high-precision predictions,a carbon-electricity cost joint optimization model is further designed to balance economic,environmental,and grid-friendly objectives.The model’s superiority was validated through a case study using real-world data from a renewable-heavy grid.Simulation results show that the proposed multi-objective strategy demonstrated a superior balance compared to baseline and benchmark models,achieving a 15.8%reduction in carbon emissions and a 5.2%reduction in economic costs,while still providing a substantial 22.2%reduction in the peak-valley difference.Its balanced performance significantly outperformed both a single-objective strategy and a state-of-the-art Model Predictive Control(MPC)benchmark,highlighting the advantage of a global optimization approach.This study provides theoretical and technical pathways for dynamic carbon factor-driven EV charging optimization.
基金Supported by the Natural Science Foundation of Liaoning Province, No. 20022063
文摘AIM： To investigate the protective effect and mechanism of alanyl-glutamine dipeptide （Ala-GIn） against hepatic ischemia-reperfusion injury in rats. METHODS： Rats were divided into group C as normal control Group （/7=16） and group G as alanyl-glutamine pretreatment 07=16）. Rats were intravenously infused with 0.9% saline solution in group C and Ala-GIn -enriched （2% glutamine） 0.9% saline solution in group G via central venous catheter for three days. Then all rats underwent hepatic warm ischemia for 30 min followed by different periods of reperfusion. Changes in biochemical parameters, the content of glutathione （GSH） and the activity of superoxide dismutase （SOD） in liver tissue, Bcl-2 and Bax protein expression and morphological changes of liver tissue were compared between both groups. RESULTS： One hour after reperfusion, the levels of liver enzymes in group G were significantly lower than those in group C （P〈0.05）. Twenty-four hours after reperfusion, the levels of liver enzymes in both groups were markedly recovered and the levels of liver enzyme in group G were also significantly lower than those in group C （P〈0.01）. One and 24 h after reperfusion, GSH content in group G was significantly higher than that in group C （P 〈0.05）. There was no statistical difference in activities of SOD between the two groups. One and 24 h after reperfusion, the positive expression rate of Bcl-2 protein was higher in group G than in group C （P〈0.05） and the positive expression rate of Bax protein was lower in group G than in group C （P〈0.05）. Histological and ultrastructural changes of liver tissue were inhibited in group C compared to group G. CONCLUSION： Our results suggest that Ala-GIn pretreatment provides the rat liver with significant tolerance to warm ischemia-reperfusion injury, which may be mediated partially by enhancing GSH content and regulating the expression of Bcl-2 and Bax proteins in the liver tissue.
文摘The aim of this study was to investigate the mechanism by which a diet inducing high hyperhomocysteinemia(HHcy)leads to the deterioration of erectile function in rats and whether this is inhibited by expression of the human tissue kallikrein-1(hKLKl)gene.We established a rat model of HHcy by feeding methionine(Met)-rich diets to male Sprague-Dawley(SD)rats.Male wild-type SD rats(WTRs)and transgenic rats harboring the hKLKl gene(TGRs)were fed a normal diet until 10 weeks of age.Then,30 WTRs were randomly divided into three groups as follows:the control(n=10)group,the low-dose(4%Met,n=10)group,and the high-dose(7%Met,n=10)group.Another 10 age-matched TGRs were fed the high-dose diet and designated as the TGR+7%Met group.After 30 days,in all four groups,erectile function was measured and penile tissues were harvested to determine oxidative stress,endothelial cell content,and penis fibrosis.Compared with the 7%Met group,the TGR+7%Met group showed diminished HHcy-induced erectile dysfunction(ED),indicating the improvement caused by hKLKl.Regarding corpus cavernosum endothelial cells,hKLKl preserved endothelial cell-cell junctions and endothelial cell content,and activated protein kinase B/endothelial nitric oxide synthase(Akt/eNOS)signaling.Fibrosis assessment indicated that hKLKl preserved normal penis structure by inhibiting apoptosis in the corpus cavernosum smooth muscle cells.Taken together,these findings showed that oxidative stress,impaired corpus cavernosum endothelial cells,and severe penis fibrosis were involved in the in duction of ED by HHcy in rats,whereas hKLKl preserved erectile function by inhibiting these pathophysiological changes.
基金the National Natural Science Foundation of China （10502053, 10372106 , 10402043）, K. C. Wong Education Foundation of Hong Kongthe Key Laboratory of High Temperature Gas Dynamics of Chinese Academy of Sciences the State Key Laboratory of Structural Analysis for Industrial Equipment of Dalian University of Technology.
文摘A method based on the computational fluid dynamics （CFD） is presented for a flexible waverider＇s design. The generating bodies of this method could be any cones. In addition, either the leading edge or the profile of the scramjet＇s inlet is used as the waverider＇s definition curve, parameterized by the quadric function, the sigmoid function or the B-spline function. Furthermore, several numerical examples are carried out to validate the method and the relevant codes. The CFD results of the configurations show that all the designs are successful. Moreover, primary suggestions are proposed for practical design by comparing the geometrical and aerodynamic performances of the conederived waveriders at Mach 6.
文摘Bridgman directional solidification of investment castings is a key technology for the production of reliable and highly efficient gas turbine blades. In this paper, a mathematical model for three-dimensional （3D） simulation of solidification process of single crystal investment castings was developed based on basic heat transfer equations. Complex heat radiation among the multiple blade castings and the furnace wall was considered in the model. Temperature distribution and temperature gradient in superalloy investment castings of single blade and multiple ones were investigated, respectively. The calculated cooling curves were compared with the experimental results and agreed well with the latter. It is indicated that the unsymmetrical temperature distribution and curved liquid-solid interface caused by the circle distribution of multiple turbine blades are probably main reasons why the stray grain and other casting defects occur in the turbine blade.
基金This work was supported by a grant from the National Natural Science Foundation of China （NSFC #81270690 ＆ NSFC #81372759）.
文摘Previous studies have shown that oxidative stress and corporal fibrosis in penile tissues of rats were key pathological factors of erectile dysfunction induced by diabetic mellitus （DMED）. Lipoxin A4 （LXA4） was reported to inhibit oxidative stress and fibrosis diseases, while whether it could exert a protective role on erectile function was not clear. Type I diabetic mellitus （DM） was induced in thirty male lO-week-old Sprague-Dawley rats using streptozotocin. Ten weeks later, twenty-two rats with DMED confirmed by an apomorphine test were divided into two groups： the DMED group （n = 11） and the DMED ＋ LXA4 group （n = 11; LXA4 injection daily for 4 weeks）. In addition, another ten age-matched rats formed the Control group. We found that erectile function was significantly impaired in the DMED group compared with the Control group, but was improved in the DMED ＋ LXA4 group. Similarly, the over-activated oxidative stress and impaired endothelial function in the DMED group were both improved in the DMED ＋ LXA4 group. Moreover, the DMED group showed serious corporal fibrosis, which was also inhibited by the treatment of LXA4 in the DMED ＋ LXA4 group. Taken together, LXA4 could exert an inhibition role on oxidative stress and fibrosis to improve DMED effectively.
文摘Our previous studies have demonstrated that erectile function was preserved in aged transgenic rats （TGR） harboring the human tissue kallikrein 1 （hKLK1）, while the molecular level of hKLK1 on corporal fibrosis to inhibit age-related erectile dysfunction （ED） is poorly understood. Male wild-type Sprague-Dawley rats （WTR） and TGR harboring the hKLK1 gene were fed to 4- or 18-month-old and divided into three groups： young WTR （yWTR） as the control, aged WTR （aWTR）, and aged TGR （aTGR）. Erectile function of all rats was assessed by cavernous nerve electrostimulation method. Masson＇s trichrome staining was used to evaluate corporal fibrosis in the corpus cavernosum. We found that the erectile function of rats in the aWTR group was significantly lower than that of other two groups. Masson＇s trichrome staining revealed that compared with those of the yWTR and aTGR groups, the ratio of smooth muscle cell （SMC）/collagen （C） was significantly lower in the aWTR group. Immunohistochemistry and Western blotting analysis were performed, and results demonstrated that expression of a-SMA was lower, while expressions of transforming growth factor-β1 （TGF-β1）, RhoA, ROCK1, p-MYPT1, p-LIMK2, and p-cofilin were higher in the aWTR group compared with those in other two groups. However, LIMK2 and cofilin expressions did not differ among three groups. Taken together, these results indicated that the RhoA/ROCK1/LIMK/cofilin pathway may be involved in the corporal fibrosis caused by advanced age, and hKLK1 may reduce this corporal fibrosis by inhibiting the activation of this pathway to ameliorate age-related ED.
基金supported by National Nature Science Foundation of China(U1136605)the Innovation Base Cultivation and Development Projectresearch on Precise genetic modification in sheep(Z171100002217072)Program for Changjiang Scholar and Innovation Research Team in University(IRT1191)
文摘Background: Black bone sheep was first discovered in Yunnan province of China in 1970, with unique black pigmentation on the body and internal organs. Endothelin 3(EDN3) has been known as a key gene causing hyperpigmentation in black bone chicken, the Silky fowl.Methods: In this study, EDN3 was employed as a candidate gene for regulating black color pigmentation. First,EDN3 was cloned from sheep to obtain the full-length cDNA by using the rapid amplification of cDNA ends(RACE).Genomic EDN3 was screened and a total of thirty predicted single nucleotide polymorphisms(SNPs) were genotyped for allele and genotype frequency analysis in a case-control study involving two black bone sheep populations. Genomic copy number analysis of EDN3 in sheep was conducted to measure the variation in copy number. EDN3 expression levels were observed among the groups in adult liver, lymph node, and kidney tissues, as well as embryo kidney samples. Also, among the tissues of black bone and non-black bone sheep.Results: The size of the full-length cDNA was 1,578 bp, which included 426 bp of 5′-untranslated region(5′-UTR),an open reading frame(ORF) of 639 bp encoding a protein of 212 amino acids, and a 3′-UTR of 513 bp. Genotype and allele frequencies of all the discovered SNPs were found insignificantly different in black bone and non-black bone sheep(P > 0.05). Genomic copy number analysis of EDN3 in sheep revealed no significant difference between the two sheep groups. No significant variations were found in the adult liver and kidney embryo samples. However,the expression in lymph node and kidney tissue was significantly higher in black bone sheep than that in non-black bone sheep(P < 0.05). Significant variations in the EDN3 expression levels were observed among the tissues of nonblack bone sheep.Conclusions: The findings of the present study indicate that unlike in Silky chickens, EDN3 is not responsible for hyperpigmentation but may play a key functional role in immune and excretory systems of black bone sheep.
基金supported by the Science and Technology Development Plan of China Railway Group Limited(Grant No.2015-kj035-g004-03).
文摘Concrete-plate fences have been widely adopted for windblown sand control and mitigation along railways.However,the inclination angles of inserting the concrete plate with respect to the vertical direction,i.e.,straight or obliquely inserted concrete plates(SIP or OIP),significantly influence the efficiency of sand-control.This study performs a comparative evaluation of the SIP and OIP sand-control fences using wind tunnel testing and field monitoring data collected from the Lanzhou–Wulumuqi High-Speed Railway Project.The results show that the fence’s ability to reduce the wind speed and the sand-retaining efficiency gradually weakens with the increasing wind speed.Compared with the SIP fence,the OIP fence has a better wind speed reduction capability,stronger ability to capture fine particles below the top of the fence;it is more efficient for sand-retaining and induces stronger eddy intensity.Generally,the wind tunnel test and field monitoring results are consistent,whereas wind tunnel tests incline to overestimate wind speed reduction and sand-control efficiency.The study also finds that the aeolian sand accumulated around the fence can weaken the protection efficiency,and hence cleaning the aeolian sand accumulated around the fence should be done periodically to ensure the designed functions.
基金Supported by Grants from Science and Technology Projects of the Medicine and Health of Shandong Province,No.2013WS0362the Natural Science Foundation of Shandong Province of China,No.30810403081the Department of Science and Technology of Shandong Province of China,No.2011GGC03085
文摘AIM:To find potential mutable sites by detecting mutations of the candidate gene in a kindred with polycystic liver disease(PCLD).METHODS:First,we chose a kindred with PCLD and obtained five venous blood samples of this kindred after the family members signed the informed consent form.In the kindred two cases were diagnosed with PCLD,and the left three cases were normal individuals.All the blood samples were preserved at-85?℃.Second,we extracted the genomic DNA from the venous blood samples of the kindred using a QIAamp DNA Mini Kit and then performed long-range polymerase chain reaction(PCR)with different primers.The exons of PKD1 were all sequenced with the forward and reverse primers to ensure the accuracy of the results.Next,we purified the PCR products and directly sequenced them using Big Dye Terminator Chemistry version 3.1.The sequencing reaction was conducted with Biomek FX(Beckman).Finally,we analyzed the results.RESULTS:A total of 42 normal exons were identified in detecting mutations of the PKD1 gene.A synonymous mutation occurred in exon 5.The mutation was a homozygous T in the proband and was C in the reference sequence.This mutation was located in the third codon and did not change the amino acid encoded by the codon.Missense mutations occurred in exons 11 and 35.These mutations were located in the second codon;they changed the amino acid sequence and existed in the db SNP library.A nonsense mutation occurred in exon 15.The mutation was a heterozygous CT in the proband and was C in the referencesequence.This mutation was located in the first codon and resulted in a termination codon.This mutation had an obvious influence on the encoded protein and changed the length of the protein from 4303 to 2246amino acids.This was a new mutation that was not present in the db SNP library.CONCLUSION:The nonsense mutation of exon 15existed in the proband and in the third individual.Additionally,the proband was heterozygous for this mutation,so the mutable site was a pathogenic mutation.
基金the National Natural Science Foundation of China(Nos.52072151,52171211,52102253,52271218,U22A20145)the Jinan Independent Innovative Team(2020GXRC015)+1 种基金the Major Program of Shandong Province Natural Science Foundation(ZR2021ZD05)the Science and Technology Program of University of Jinan(XKY2119).
文摘Focused exploration of earth-abundant and cost-efficient non-noble metal electrocatalysts with superior hydrogen evolution reaction(HER)performance is very important for large-scale and efficient electrolysis of water.Herein,a sandwich composite structure(designed as MS-Mo2C@NCNS)ofβ-Mo2C hollow nanotubes(HNT)and N-doped carbon nanosheets(NCNS)is designed and prepared using a binary NaCl–KCl molten salt(MS)strategy for HER.The temperature-dominant Kirkendall formation mechanism is tentatively proposed for such a three-dimensional hierarchical framework.Due to its attractive structure and componential synergism,MS-Mo2C@NCNS exposes more effective active sites,confers robust structural stability,and shows significant electrocatalytic activity/stability in HER,with a current density of 10 mA cm-2 and an overpotential of only 98 mV in 1 M KOH.Density functional theory calculations point to the synergistic effect of Mo2C HNT and NCNS,leading to enhanced electronic transport and suitable adsorption free energies of H*(ΔGH*)on the surface of electroactive Mo2C.More significantly,the MS-assisted synthetic methodology here provides an enormous perspective for the commercial development of highly active non-noble metal electrocatalysts toward efficient hydrogen evolution.
基金financially supported by the National Natural Science Foundation of China(No.51374173)。
文摘The microstructure and microhardness of directionally solidified NiAl-W eutectic alloys at growth rates of 2-25μm·s^-1 were investigated by a Bridgman crystal growing facility at a temperature gradient of 300 K·cm^-1.In view of the competitive growth between W dendritic and eutectic phases,W dendritic phase was eliminated,whereas the fully eutectic phase was prominent in the steady progress of the directionally solidified NiAl-W eutectic alloys.As the growth rate(V)increased,both the structure and solid/liquid interface of the directionally solidified NiAl-W eutectic alloys changed from planar to cellular.Both the fibrous spacing(d)and the diameter(a)decreased with increase in growth rate(V).The Vickers microhardness(H)of the directionally solidified NiAl-W eutectic alloys decreased with fibrous spacing(d)or diameter(a)increasing.The relationships of H to d and a were H=371.58 d^(-0.09)and H=297.70 a^(-0.09),respectively.
文摘Lead halide perovskites MAPbX_(3)(MA = CH_(3)NH_(3) or Cs;X = I, Br, Cl) are well considered to be potential candidates for photocatalytic reaction due to its excellent photoelectrical properties, but they still suffer from the low charge separation efficiency and slow catalytic reaction dynamics. To tackle the drawbacks, herein, MAPbBr_(3)/carbon sphere(CS) composite photocatalysts using glucose as the carbon source were elaborately designed and fabricated via a dry mechanochemical grinding process. The interfacial interaction Pb-O-C chemical bonds were constructed between MAPbBr_(3) and the carbon sphere surface containing organic functional groups. By optimizing the content of CSs, the enhanced photocatalytic degradation kinetic rate of Malachite Green(MG) pollutants(92% within 20 min) for MAPbBr_(3)/CS x( x = 17 wt.%) is about 3.6-fold of that for pristine MAPbBr_(3), which is attributed to the corporative adsorption and enhanced carrier transportation and separation of MAPbBr_(3)/CS x. Furthermore, the possible degradation mechanism was proposed on basis of the electrochemical, mass spectrometry and optical characterization results. Owing to the robust interfacial interaction, effective electron extraction rate( k et = 4.6 × 10^(7) sec^(-1)) from MAPbBr_(3) to CS can be established, which driven oxygen activation where superoxide radicals(·O^(2-)) played an important role in MG degradation. It is expected that mechanochemistry strategy may provide a new route to design efficient lead halide perovskite-carbon or metal oxide or sulfide composite photocatalysts.
基金supported by the National Natural Science Foundation of China(Grant Nos.52301380 and 11602277).
文摘A hybrid approach based on the immersed boundary method(IBM)is developed for computation of flow-induced sound around moving bodies.In this method,a high-fidelity direct numerical simulation(DNS)solver is used to simulate the incompressible flow field.The sound field is predicted by discretizing acoustic perturbation equations(APEs)with dispersionrelation-preserving space scheme and low-dispersion and low-dissipation Runge-Kutta time integration.A sharp-interface IBM based on ghost-cell is implemented for present two-step DNS-APE approach to deal with complex moving bodies with Cartesian grids.The present method is validated through simulations of sound generation caused by flow past a rotating cylinder,an oscillating cylinder,and tandem oscillating and stationary cylinders.The sound generated by typical kinds of complicated bio-inspired locomotions,i.e.,flapping flight by wings of varied shapes and collective undulatory swimming in tandem,are investigated using present method.The results demonstrate potential of the hybrid approach in addressing flowinduced sound generation and propagation with complex moving boundaries in a fluid medium,especially for the sound characteristics of bio-mimetic flows,which might shed lights on investigations on bio-acoustics,ethology of complex animal system,and related bio-mimetic design for quietness.
