Effects of platelet-rich plasma on in vitro proliferation and migration of fibroblasts from human chronic refractory wound granulation tissue

Objective:To observe the effects of platelet-rich plasma(PRP)on in vitro proliferation and migration of fibroblasts from human chronic refractory wound granulation tissue.Methods:Fibroblasts were separated from human chronic refractory wound granulation tissue and then were identified.The obtained fibroblasts were divided into fetal bovine serum(FBS)group,hydrogel group and PRP group,and the three groups were cultured with culture mediums containing FBS,hydrogel and PRP respectively,in order to observe the growth of fibroblasts.The wound scratch assay was used to observe the migration of fibroblasts.Results:PRP group had more fibroblasts than FBS group and hydrogel group since Day 5 of culture,and exhibited greater fibroblast scratch migration area than FBS group on 48 h and 72 h of wound scratch assay(all p<.05).Conclusions:Compared with FBS,human fibroblasts cultured by PRP can more effectively promote the proliferation and migration of fibroblasts.

Study on the mechanism of microporous sheep ADM combined with hUCMSC in promoting wound healing

Objective:To explore the therapeutic mechanism of microporous sheep acellular dermal matrix(ADM)combined with human umbilical cord mesenchymal stem cell(hUCMSC)to promote the healing of full-thickness skin defect.Methods:hUCMSC was co-cultured on microporous sheep ADM to form composite biological dressings.Seventy-two nude mice were selected to make full-thickness skin injury models and randomly divided into 3 groups(hUCMSC+microporous sheep ADM group,sheep ADM group and iodophor gauze group),with 24 mice in each group.The wound healing rate of each group was detected at 14 d,21 d and 28 d after operation,qRT-PCR technique was used to detect the expression of Bax and Bcl-2 in the wound tissues,and the immunohistochemical staining technique was used to detect the expression of Collagen I and vascular endothelial growth factor(VEGF).Data were analyzed with one-way ANOVA and t test.Results:At 14 d after operation,the wound healing rate of the hUCMSC+microporous sheep ADM group was(65.34±14.72)%,which was significantly higher than that of the iodophor gauze group[(37.54±10.21)%],and higher than that of the sheep ADM group[(49.08±11.16)%],the differences were statistically significant(t=19.52,14.72;p<.05).With the gradual healing of the wound,at 28 d after operation,the wound healing rate of the hUCMSC+microporous sheep ADM group was(98.63±15.41)%,which was significantly higher than that of the iodophor gauze group[(81.74±16.27)%],and higher than that of the sheep ADM group[(63.47±14.80)%],the differences were statistically significant(t=-16.42,20.35;p<.05).The expression of Bax in the wound tissues of the hUCMSC+microporous sheep ADM group was significantly reduced,especially at 21 d after operation,the expression level was 0.25±0.06,which was significantly lower than the iodophor gauze group(0.53±0.16)and the sheep ADM group(0.41±0.12),the differences were statistically significant(t=3.52,-2.83;p<.05).The expression of Bcl-2 in the wound tissues of the hUCMSC+microporous sheep ADM group was significantly higher than those of the other two groups,especially at 21 d after operation,the expression level was 0.63±0.19,which was significantly higher than the iodophor gauze group(0.34±0.09)and the sheep ADM group(0.46±0.13),the differences were statistically significant(t=5.31,-6.07;p<.05).Immunohistochemical detection showed that the expression of Collagen I and VEGF in the hUCMSC+microporous sheep ADM group was slightly more than that of the sheep ADM group and the iodophor gauze group,but the effect was not remarkable.Conclusions:hUCMSC+microporous sheep ADM composite dressing can promote the healing of the full-thickness skin injury and reduce the production of apoptotic cells by carrying hUCMSC.

Successful treatment of severe burn patients with multiple organ dysfunction syndrome:A case report

Multiple organ dysfunction syndrome is the presence of altered organ function of two or more organ systems in acute ill patients with severe trauma,burn,shock and infection.In this case,the patient with burn area amounted to 95%and the third-degree burn was up to 90%.He underwent gastrointestinal tract,blood clotting,lung,brain,heart,liver dysfunction,and cardiac arrest for 30 minutes during the courses of treatment,and was discharged from the hospital after 108 days on the basis of comprehensive treatment and repeated skin grafting.

Synergy between CSST galaxy survey and gravitational-wave observation: Inferring the Hubble constant from dark standard sirens

Gravitational waves(GWs) from compact binary coalescences encode the absolute luminosity distances of GW sources. Once the redshifts of GW sources are known, one can use the distance-redshift relation to constrain cosmological parameters. One way to obtain the redshifts is to localize GW sources by GW observations and then use galaxy catalogs to determine redshifts from a statistical analysis of redshift information of the potential host galaxies, commonly referred to as the dark siren method. The third-generation(3G) GW detectors are planned to work in the 2030s and will observe numerous compact binary coalescences.Using these GW events as dark sirens requires high-quality galaxy catalogs from future sky survey projects. The China Space Station Telescope(CSST) will be launched in 2024 and will observe billions of galaxies within a 17500 deg^(2) survey area with redshift up to z ~ 4, providing photometric and spectroscopic galaxy catalogs. In this work, we simulate the CSST galaxy catalogs and the 5-year GW data from the 3G GW detectors and combine them to infer the Hubble constant(H_(0)). Our results show that the measurement precision of H0could reach the sub-percent level, meeting the standard of precision cosmology. We conclude that the synergy between CSST and the 3G GW detectors is of great significance in measuring the Hubble constant.

二维活塞泵用滚子-凸轮轨道机构的建模和验证（英文）

目的:由于液压行业对高速重载的要求越来越高,传统轴向柱塞泵中存在的润滑与泄漏的矛盾也越发明显。针对传统轴向柱塞泵中因结构产生的倾斜力、低功率密度、恶劣的摩擦副工况、较大的流量脉动等限制,本文旨在提出一种具有内力平衡、功率密度高、无纯粹的滑动摩擦副且工况优秀、能消除结构性流量脉动等优点的二维活塞泵,并通过对其工作原理的详细分析,探讨其具有上述优点的理论依据。创新点:1.提出二维活塞泵;该泵利用二维运动转换机构中活塞部件的二维运动,同时实现了吸排油功能和配流功能,提高了集成化;通过其活塞旋转1周可以使泵吸排油4次的结构设计,提高了功率密度;轴向与轴向对称的独特结构布局,实现了内力平衡,消除了传统轴向柱塞泵中无法消除的倾覆力偶;相对于传统轴向柱塞泵,吸排油与配流功能的集成减少了摩擦副的数量,且消除了纯粹的滑动摩擦副,打破了PV值的限制,意味着二维活塞泵有着实现更大流量压力分布的潜力。2.提出二维活塞泵运动转换机构中的锥滚子-凸轮接触结构,优化二维活塞泵运动转换机构的受力条件;3.建立二维活塞泵运动转换机构中锥滚子-凸轮接触副的通用型数学模型,通过运动学分析建立精确的凸轮表面模型(即二维活塞泵的运动学模型),为二维锥滚轮活塞泵的结构设计和进一步的静、动力学的研究提供理论基础。4.消除结构性流量脉动。方法:1.通过对二维活塞泵结构与工作原理的理论分析,讨论其相对于传统轴向柱塞泵所具有的优点。2.通过跑合实验,验证锥滚子-凸轮接触结构具有的受力条件。3.通过运动学分析与空间几何关系变换推导,得到运动转换机构中具有普遍指导意义的接触副的通用数学模型。4.通过实验曲线与理论曲线的对比,验证接触副数学模型的正确性与二维活塞泵所具有的消除结构流量脉动的潜力。5.通过滤波处理与模拟仿真,验证二维活塞泵能否消除结构性流量脉动。结论:1.二维活塞泵具有功能集成化高、内力平衡、功率密度高、无纯粹的滑动摩擦副且能消除流量脉动的优点。2.运动转换机构中锥滚子-凸轮接触结构具有更好的受力条件。3.建立的接触副数学模型可以指导二维活塞泵中运动转换机构的加工,且对二维活塞泵进一步的运动学与动力学的研究具有指导意义。4.二维活塞泵能消除结构性流量脉动。

Prospects for improving cosmological parameter estimation with gravitational-wave standard sirens from Taiji

Taiji,a space-based gravitational-wave observatory,consists of three satellites forming an equilateral triangle with arm length of 3×10^6 km,orbiting around the Sun.Taiji is able to observe the gravitationalwave standard siren events of massive black hole binary(MBHB)merger,which is helpful in probing the expansion of the universe.In this paper,we preliminarily forecast the capability of Taiji for improving cosmological parameter estimation with the gravitational-wave standard siren data.We simulate fiveyear standard siren data based on three fiducial cosmological models and three models of MBHB’s formation and growth.It is found that the standard siren data from Taiji can effectively break the cosmological parameter degeneracies generated by the cosmic microwave background(CMB)anisotropies data,especially for dynamical dark energy models.The constraints on cosmological parameters are significantly improved by the data combination CMB+Taiji,compared to the CMB data alone.Compared to the current optical cosmological observations,Taiji can still provide help in improving the cosmological parameter estimation to some extent.In addition,we consider an ideal scenario to investigate the potential of Taiji on constraining cosmological parameters.We conclude that the standard sirens of MBHB from Taiji will become a powerful cosmological probe in the future.

Forecast for cosmological parameter estimation with gravitational-wave standard sirens from the LISA-Taiji network

LISA and Taiji are expected to form a space-based gravitational-wave(GW)detection network in the future.In this work,we make a forecast for the cosmological parameter estimation with the standard siren observation from the LISA-Taiji network.We simulate the standard siren data based on a scenario with configuration angle of 40°between LISA and Taiji.Three models for the population of massive black hole binary(MBHB),i.e.,popⅢ,Q3d,and Q3nod,are considered to predict the events of MBHB mergers.We find that,based on the LISA-Taiji network,the number of electromagnetic(EM)counterparts detected is almost doubled compared with the case of single Taiji mission.Therefore,the LISA-Taiji network’s standard siren observation could provide much tighter constraints on cosmological parameters.For example,solely using the standard sirens from the LISA-Taiji network,the constraint precision of H;could reach 1.3%.Moreover,combined with the CMB data,the GW-EM observation based on the LISA-Taiji network could also tightly constrain the equation of state of dark energy,e.g.,the constraint precision of w reaches about 4%,which is comparable with the result of CMB+BAO+SN.It is concluded that the GW standard sirens from the LISA-Taiji network will become a useful cosmological probe in understanding the nature of dark energy in the future.

Novel synthesis of CuW composite reinforced with lamellar precipitates via aluminothermic reduction

The in situ synthesized reinforced phases in the matrix have the advantages of uniform dispersion and good interfacial bonding.Aiming at in situ synthesizing reinforced phases in CuW composite,a novel methodology for direct synthetization of CuW composite reinforced with lamellar precipitates by aluminothermic reduction is proposed,and CuW composites and their slags were systematically analyzed.The results indicate that,at temperatures of above 1800 K,the mole percentage of Al,copper oxides,tungsten oxide,and CuO·Al_(2)O_(3)increased rapidly with temperature increasing,which was not conducive to CuO and W0_(3)thermite reduction.

Impacts of gravitational-wave standard siren observations from Einstein Telescope and Cosmic Explorer on weighing neutrinos in interacting dark energy models

Multi-messenger gravitational wave(GW)observation for binary neutron star merger events could provide a rather useful tool to explore the evolution of the Universe.In particular,for the third-generation GW detectors,i.e.the Einstein Telescope(ET)and the Cosmic Explorer(CE),proposed to be built in Europe and the U.S.,respectively,lots of GW standard sirens with known redshifts could be obtained,which would exert great impacts on the cosmological parameter estimation.The total neutrino mass could be measured by cosmological observations,but such a measurement is model-dependent and currently only gives an upper limit.In this work,we wish to investigate whether the GW standard sirens observed by ET and CE could help improve the constraint on the neutrino mass,in particular in the interacting dark energy(IDE)models.We find that the GW standard siren observations from ET and CE can only slightly improve the constraint on the neutrino mass in the IDE models,compared to the current limit.The improvements in the IDE models are weaker than those in the standard cosmological model.Although the limit on neutrino mass can only be slightly updated,the constraints on other cosmological parameters can be significantly improved by using the GW observations.