超声斑点追踪成像技术评价主动脉瓣狭窄患者左心房功能的临床研究

目的应用超声斑点追踪成像(STI)技术评价主动脉瓣狭窄(AS)患者左心房功能,早期预测肺循环障碍及肺水肿的发生。方法选取30例AS患者(AS组)及30例健康志愿者(对照组)作为研究对象。采用超声诊断仪分别取心尖四腔、五腔及心底短轴切面图测量。记录主动脉瓣口面积(Aa)、主动脉瓣口血流峰速(Av)、左心室射血分数(LVEF)法、二尖瓣口血流E峰/A峰(E/A)、左心房收缩末期容积(LAVS)、左心房舒张末期容积(LAVD)、左心房P容积(LAVp)、左心房主动射血分数(LAAEF)及左心房被动射血分数(LAPEF)。应用Q-LAB软件分析左心室收缩期左心房峰值变形率、左心室舒张早期左心房峰值变形率及左室舒张晚期左心房峰值变形率。结果①AS组较对照组Aa减小,Av增大,E/A减小,LVEF减小(P<0.05);②两组LAVD、LAVp、LAVS、LAPEF比较,差异无统计学意义(P>0.05),AS组较对照组LAAEF减低(P<0.05);③AS组较对照组左心室收缩期左心房峰值变形率、左心室舒张早期左心房峰值变形率、左心室舒张晚期左心房峰值变形率降低。结论AS患者应用STI技术测量各指标有变化。STI技术能早期发现AS患者左心房功能受损,有利于预测肺循环及肺水肿的发生,延缓右心衰、改善预后。

Large-scale synthesis of nickel sulfide micro/nanorods via a hydrothermal process

Rhombohedral-phase NiS micro/nanorods were synthesized on a large scale through a hydrothermal method using NiCl2·6H2O and thiourea crystals as starting precursors. Recrystallized thiourea was observed to play an important role in the formation of mi- cro/nanosized rods and flower-like structures. The molar ratio and reaction temperature of the precursors influenced the morphology and phase of NiS products. Pure rhombohedral NiS micro/nanorods were obtained on a large scale when the molar ratio between NiCl2·6H2O and thiourea crystals was fixed at 2：1, and the mixture was heated at 250℃ for 5 h. Flower-like NiS nanostructures were formed when the molar ratio between NiCl2·6H2O and thiourea crystals was maintained at 1：1. The Raman and Fourier-transform infrared （FTIR） spectra of the as-prepared rhombohedral NiS micro/nanorods were collected, and their magnetic properties were investigated. The results showed that the FTIR absorption peaks of the as-prepared product are located at 634 cm^-1 and their Raman peaks are located at 216 and 289 cm^-1; the as-prepared NiS micro/nanorods exhibited weak ferromagnetic behavior due to the size effect.

Fast achievement of quantum state transfer and distributed quantum entanglement by dressed states

We propose schemes to realize quantum state transfer and prepare quantum entanglement in coupled cavity and cavity-fiber-cavity systems,respectively,by using the dressed state method.We first give the expression of pulses shape by using dressed states and then find a group of Gaussian pulses that are easy to realize in experiment to replace the ideal pulses by curve fitting.We also study the influence of some parameters fluctuation,atomic spontaneous emission,and photon leakage on fidelity.The results show that our schemes have good robustness.Because the atoms are trapped in different cavities,it is easy to perform different operations on different atoms.The proposed schemes have the potential applications in dressed states for distributed quantum information processing tasks.

Matrix Effect on Polydiarylfluorenes Electrospun Hybrid Microfibers: From Morphology Tuning to High Explosive Detection Efficiency

Precisely optimizing the morphology of functional hybrid polymeric systems is crucial to improve its photophysical property and further extend their optoelectronic applications. The physic-chemical property of polymeric matrix in electrospinning (ES) processing is a key factor to dominate the condensed structure of these hybrid microstructures and further improve its functionality. Herein, we set a flexible poly(ethylene oxide) (PEO) as the matrix to obtain a series of polydiarylfluorenes (including PHDPF, PODPF and PNDPF) electrospun hybrid microfibers with a robust deep-blue emission. Significantly different from the rough morphology of their poly(N-vinylcarbazole) (PVK) ES hybrid fibers, polydiarylfluorenes/PEO ES fibers showed a smooth morphology and small size with a diameter of 1∼2 µm. Besides, there is a relatively weak phase separation under rapid solvent evaporation during the ES processing, associated with the hydrogen-bonded-assisted network of PEO in ES fibers. These relative “homogeneous” ES fibers present efficient deep-blue emission (PLQY>50%), due to weak interchain aggregation. More interestingly, low fraction of planar (β) conformation appears in the uniform PODPF/PEO ES fibers, induced by the external traction force in ES processing. Meanwhile, PNDPF/PEO ES fibers present a highest sensitivity than those of other ES fibers, associated with the smallest diameter and large surface area. Finally, compared to PODPF/PVK fibers and PODPF/PEO amorphous ES fibers, PODPF/PEO ES fibers obtained from DCE solution exhibit an excellent quenching behavior toward a saturated DNT vapor, mainly due to the synergistic effect of small size, weak separation, β-conformation formation and high deep-blue emission efficiency.

Will China achieve its 2060 carbon neutral commitment from the provincial perspective?

China has pledged to peak carbon emissions before 2030 and strive to achieve carbon neutrality before 2060.However,the significant variations of provincial carbon emissions make it unclear whether they can jointly fulfill the national carbon peak and neutrality goal.Thus,this study predicts the emission trajectories at provincial level in China by employing the extended STIRPAT(Stochastic Impacts by Regression on Population,Affluence,and Technology)model to see the feasibility and time of reaching peak carbon emissions and carbon neutrality.We found that most provinces can achieve peak emission before 2030 but challenging to achieve carbon neutrality before 2060,even considering the ecological carbon sink.The provincial neutrality time is concentrated between 2058 and 2070;the sooner the carbon emission peaks,the earlier the carbon neutral will be realized.The aggregated carbon emissions at provincial level show that China can achieve its carbon emission peak of 9.64-10.71 Gt before 2030,but it is unlikely to achieve the carbon neutrality goal before 2060 without carbon capture,utilization,and storage(CCUS).With high CCUS development,China is expected to achieve carbon neutrality in 2054-2058,irrespective of the socio-economic scenarios.With low CCUS development,China's carbon neutrality target will be achieved only under the accelerated-improvement scenario,while it will postpone to 2061 and 2064 under the continued-improvement and the business-as-usual scenarios,respectively.

Induction of Protection against Paraquat-induced Oxidative Damage by Abscisic Acid in Maize Leaves is Mediated through Mitogen-activated Protein Kinase

Mitogen-activated protein kinase （MAPK） cascade has been shown to be important components in stress signal transduction pathway. In the present study, protection of maize seedlings （Zea mays L.） against paraquat-generated oxidative toxicity by abscisic acid （ABA）, its association with MAPK and ZmMPK5, a candidate for MAPK were investigated. Treatment of maize leaves with exogenous ABA led to significant decreases in the content of malondialdehyde, the percentage of ion leakage and the level of protein oxidation （in terms of carbonyl groups） under paraquat （PQ） stress. However, such decreases were blocked by the pretreatment with two MAPK kinase inhibitors PD98059 and U0126. The damage caused by PQ was further aggravated by inhibitors. Two inhibitors also suppressed the total activities of the antioxidant enzymes superoxide dismutase （SOD, EC 1.15.1.1）, catalase （CAT, EC 1.11.1.6）, ascorbate peroxidase （APX, EC 1.11.1.tl）, and glutathione reductase （GR, EC 1.6.4.2）. Besides, treatment with PQ stimulated the activation of a 46 kDa MAPK, which was identified as ZmMPK5 by in-gel kinase assay with immunoprecipitation. These results reveal that ABA-induced protection against PQ-generated oxidative damage is mediated through MAPK cascade in maize leaves, in which ZmMPK5, a candidate for MAPK, is demonstrated to be involved.

GLABROUS INFLORESCENCE STEMS regulates trichome branching by genetically interacting with SIM in Arabidopsis

Arabidopsis trichomes are large branched single cells that protrude from the epidermis. The first mor- phological indication of trichome development is an increase in nuclear content resulting from an initial cycle of endoreduplication. Our previous study has shown that the C2H2 zinc finger protein GLABROUS INFLORESCENCE STEMS (GIS) is required for trichome initiation in the inflorescence organ and for trichome branching in response to gibberellic acid signaling, although GIS gene does not play a direct role in regulating trichome cell division. Here, we describe a novel role of GIS, controlling trichome cell division indirectly by interacting genetically with a key endoreduplication regulator SIAMESE (SIM). Our molecular and genetic studies have shown that GIS might indireclty control cell division and trichome branching by acting downstream of SIM. A loss of function mutation of SIM signficantly reduced the expression of GIS. Futhermore, the overexpression of GIS rescued the trichome cluster cell phenotypes of sim mutant. The gain or loss of function of GIS had no significant effect on the expression of SIM. These results suggest that GIS may play an indirect role in regulating trichome cell division by genetically interacting with SIM.

Dural arteriovenous fistula disguised as cerebral venous sinus thrombosis

Dural arteriovenouscommunications betweenfistulas （DAVFs） are directthe intracranial arterial andvenous systems without an intervening nidus. Clini-cians sometimes fail to give a correct diagnosis ofDAVF. Given the similarity of their clinical andmagnetic resonance imaging （MRI） manifestations,diagnostic confusion may arise between DAVF andcerebral venous sinus thrombosis （CVST） （Simonet al., 2009）.