Maternal Vascular Dysfunction in Congenital Heart Defects

Background:Research on fetal congenital heart defect(CHD)mostly focuses on etiology and mechanisms.However,studies on maternal complications or pathophysiology are limited.Our objective was to determine whether vascular dysfunction exists in pregnant women carrying a fetus with congenital heart defects.Methods:We conducted a case-control study.27 cases of pregnant women carrying a fetus with major CHD admitted to our hospital for delivery between April 2021 and August 2022 were selected.Every case was matched with about 2 pregnant complication-free controls without fetal abnormalities.The proangiogenic and anti-angiogenic factors and pregnancy outcomes were compared.Results:The proangiogenic factors include vascular endothelial growth factor(VEGF)and placental growth factor(PlGF).The anti-angiogenic factors involve soluble fms-like tyrosine kinase 1(sFlt-1)and soluble endoglin(sEng).No differences were found in maternal plasma concentrations of PlGF,VEGF,and sFlt-1 between case-control groups when analyzed at 36 weeks≤gestational age(GA)<39 weeks and 39 weeks≤GA≤41 weeks.The concentrations of sEng in maternal plasma in the fetal CHD group were significantly higher than those in the control group:0.60(0.77)vs.0.32(0.26)ng/ml at 36 weeks≤GA<39 weeks,p=0.001 and 0.75(0.55)vs.0.28(0.27)ng/ml at 39 weeks≤GA≤41 weeks,p<0.001.Conclusion:Vascular dysfunction exists in pregnant women with fetal congenital heart defects,manifesting significantly elevated sEng concentration at delivery.

Large area^(3)He tube array detector with modular design for multi‑physics instrument at CSNS

The multi-physics instrument(MPI)is the first user cooperative instrument at the China Spallation Neutron Source(CSNS).It was designed to explore the structures of complex materials at multiple scales based on the neutron total scattering technique.This imposes the requirements for the detector,including a high detection efficiency to reduce the measurement time and a large solid angle coverage to cover a wide range of momentum transfers.To satisfy these demands,a large-area array of 3He-filled linear position-sensitive detectors(LPSDs)was constructed,each with a diameter of 1 inch and pressure of 20 atm.It uses an orbicular layout of the detector and an eight-pack module design for the arrangement of 3He LPSDs,covering a range of scattering angles from 3°to 170°with a total detector area of approximately 7 m2.The detector works in air,which is separated from the vacuum environment to facilitate installation and maintenance.The characteristics of the MPI detector were investigated through Monte Carlo(MC)simulations using Geant4 and experimental measurements.The results suggest that the detectors are highly efficient in the wavelength range of the MPI,and an efficiency over 25%is achievable for above 0.1 A neutrons.A minimal position resolution of 6.4 mm full width at half maximum(FWHM)along the tube length was achieved at a working voltage of 2200 V,and a deviation below 2 mm between the real and measured positions was attained in the beam experiment.The detector module exhibited good consistency and an excellent counting rate capacity of up to 80 kHz,which satisfied the requirements of experiments with a high event rate.Observations of its operation over the past year have shown that the detector works steadily in sample experiments,which allows the MPI to serve the user program successfully.

透皮给药实心微针阵列的紫外压印工艺方法

文中提出了一种紫外压印技术成型透皮给药实心微针的工艺方法,以C-coating光刻胶作为微针成型的原材料,采用微机电技术加工的聚二甲基硅氧烷(PDMS)微针模具,探究了紫外压印实验中影响微针成型质量的工艺条件。实验结果表明,利用C-coating光刻胶抽真空12 min以上,紫外曝光170~200 s时,制备的紫外压印微针的高度能达到230μm。通过纳米压痕力学测试和猪皮离体皮肤穿刺实验,证明这种紫外压印微针的针尖在承受50 mN的力时没有发生断裂破坏现象,并且能够顺利刺入猪皮达到良好的透皮给药效果,为紫外压印技术成型透皮给药微针提供了一定的技术参考。

基于交联透明质酸的微针制备及性能

新型水凝胶微针具有安全包裹多相药物、药物持续、可控释放等优点,在微针透皮给药领域极具应用潜力。文中重点研究了交联透明质酸微针贴片的优化工艺,并对微针贴片进行了性能评价。在碱性条件下使用1,4-丁二醇二缩水甘油醚(BDDE)为交联剂对透明质酸进行交联,利用微浇注法制备交联透明质酸微针(cHA-MN),并优化其工艺。对所制备的微针贴片进行了外观形貌、力学性能、体外刺入性能及溶胀性能表征,验证其能否满足使用要求。实验结果表明,使用最优工艺制备的交联透明质酸微针贴片力学性能优良,可以顺利刺破皮肤,并实现溶胀功能。使用制备的微针搭载2.5%的右旋布洛芬药物,体外透皮扩散结果表明,微针在0~6 h释放出约38%药物,随后以一定速度缓慢释放至42 h,累计释放率约90%。

Determination of Aromatic Components of Rosa davurica Pall. by Headspace Solid Phase Microextraction Combined with GC-MS

[Objectives] To determine the aromatic components of Rosa davurica Pall. [Methods] 42 kinds of aromatic components were identified from the flowers of R. davurica by headspace solid phase microextraction( HS-SPME) combined with gas chromatography-mass spectrometry( GC-MS). The main compounds were alcohols( 54. 88%) and aldehydes( 19. 55%). [Results] The top five components with the highest relative content were phenylethyl alcohol( 12. 69%),geraniol( 9. 85%),citronellol( 8. 80%),nerol( 7. 84%) and 2-n-pentylfuran( 7. 45%). [Conclusions] Headspace solid phase microextraction( HS-SPME) combined with gas chromatography-mass spectrometry( GC-MS) can provide basis for further development and utilization of R. davurica.

Prenatal congenital heart defects in southern China:detection rate and termination of preqnancy,2006-2016

Objective Congenital heart defect (CHD) is one of the most common birth anomalies with high morbidity and mortality. Previous studies of CHD mostly focus on the postnatal prevalence, mortality and successful rate of operation, etc. This study aimed to explore the detection rate of prenatal CHD and CHD factors that attribute to termination of pregnancy (TOP).

Screening Coarctation of Aorta with Clinical and Echocardiographic Profiles in Infants:A Pilot Study

Aim:To determine the profiles of clinical features including four-limb blood pressure(BP),saturations of peripheral oxygen(SpO2),and echocardiographic features in infants with coarctation of aorta(CoA)to facilitate congenital heart diseases screening.Methods:The charts of infants with CoA were retrospectively reviewed.All in-hospital infants suspected of congenital heart diseases by clinical teams were prospectively measured of four limbs BPs and SpO2 in a regional cardiac transferring center during 2013 and 2019.Echocardiography as a gold standard test was followed within 2 days after suspicion.All infants were divided into non-significant CoA group or significant CoA group based on the difference of BPs between right arm and lower limbs.Predictors of nonsignificant CoA were determined with multivariable logistic regression.Results:One hundred thirty-three infants with CoA were identified.The BPs on upper limbs were higher than those on lower limbs(P=0.001).No statistical difference in SpO2 was found between four limbs.Fifty-three(39.8%)infants presented with significant CoA.Thirty-four infants presented with low SpO2 and 26 of 34 presented with non-significant CoA.Small ascending aorta diameter[0.070(95%CI:0.005–0.136),P=0.036]was an independent risk factors for non-significant CoA.Eighteen(13.5%)infants with CoA didn’t present with any of the BP difference,low SpO2,murmur,or weak femoral pulse.Conclusion:Less than half of the infants with CoA presented with a significant BP difference.Another one fifth presented with low SpO2.Small ascending aorta diameter was an independent factor for non-significant CoA.

Effects of Different Seedling Raising Methods on Seedling Growth of Two Kinds of Fritillaria

[Objectives] To reveal the effects of film mulching and open ground seedling raising on the differences between Fritillaria przewalskii Maxim. and Fritillaria pallidiflora Schrenkf., find the optimal seedling raising method, and provide scientific basis for standard seedling raising technique and protecting wild resources of Fritillaria. [Methods] This experiment counted the seedling emergence number and calculated the seedling emergence indicator and the yield. [Results] The results showed that under the condition of film mulching and open ground seedling raising, the changes of Fritillaria seedlings showed an "S" curve, conforming to the Logistic equation, and the rapid growth period appeared 5-13 d after seedling emergence. Compared with the open ground seedling raising, the seedlings of F. przewalskii Maxim. and F. pallidiflora Schrenkf. raised through film mulching emerged 2-4 d earlier, and the yield increased by 56.8% and 21.71%, respectively, and the individual quality was excellent. [Conclusions] The film mulching of F. przewalskii Maxim. and F. pallidiflora Schrenkf. has great significance to protect the wild resources of Fritillaria in Eryin Mountain Area. It is recommended to adopt the film mulching method for Fritillaria seedling raising, to reduce the yield decline due to lodging, and adopt sun-shading net covering after sowing.

A Rare Case of Transcatheter Closure of Both Inlet and Outlet of a Left Coronary Artery-to-Left Ventricular Fistula with Giant Coronary Artery Aneurysm

A congenital coronary artery fistula(CCAF)combined with giant coronary aneurysm(CAA)is a rare congenital cardiac abnormality.We reported an 8-year-old patient who underwent transcatheter closure of both inlet and outlet of a proximal left coronary artery(LCA)-to-left ventricular(LV)fistula with CAA of 41 mm×28 mm in diameter,during which acute occlusion of left anterior descending coronary artery(LAD)occurred immediately after device implantation at the inlet of fistula.We managed to prevent the patient from major adverse cardiac events by conservative therapy with dual antiplatelet agents instead of surgical removal of the device.The patient recovered well and had been follow-up for 2 years with no late complications reported.

Optimizing strain response in lead-free(Bi_(0.5)Na_(0.5))TiO_(3)-BaTiO_(3)-NaNbO_(3)solid solutions via ferroelectric/(non-)ergodic relaxor phase boundary engineering

Lead-free bismuth sodium titanate(Bi_(0.5)Na_(0.5))TiO_(3)(BNT)and related solid solutions are potential piezoelectric materials for such applications as actuators and transducers if their excellent strain responses and piezoelectric properties can be optimized.In this work,a large strain response of 0.61%is achieved in lead-free(0.94-x%)(Bi_(0.5)Na_(0.5))TiO_(3)-0.06BaTiO_(3)-x%NaNbO_(3)(x=0 e6,BNT-6BT-xNN)ceramics with the composition of x=3.5 in a pseudo-cubic structure.Coexistence of ferroelectric(FE)and relaxor(RE)domain structures is observed in all the unpoled ceramics and the enhanced strain response is believed to be related to the evolution of the ergodic relaxor(ER)and non-ergodic(NR)states thanks to the substitution of antiferroelectric NN.BNT-6BT-3.5NN is a critical composition near the FE/NR/ER phase boundary close to room temperature(RT)and its high strain response arises from a synergistic combination of a reversible electric-field-induced phase transition and an active domain switching in the mixed NR/ER state.This work provides new insights into the dynamic interplay between mesoscopic domains and macroscopic electrical properties in the BNT-based piezoceramics.

Development of 3He-filled linear position-sensitive detector for neutron scattering instruments at CSNS

Background Helium-3-filled linear position-sensitive detectors(LPSDs)have been widely applied to neutron scattering instruments in recent decades owing to the high detection efficiency,the excellent neutron/gamma discrimination,and the ability to construct the detector with large area coverage.More than 65%of neutron instruments at the China Spallation Neutron Source(CSNS)require ^(3)He LPSDs for the building of the detector system.The detector of a neutron scattering instrument is normally an array detector composed of a large number of ^(3)He LPSDs.However,no appropriate substitute detector is available for the ^(3)He LPSD for operation over a short period,and its specifications need to be customized to satisfy the requirements of different instruments.This necessitates the development of ^(3)He LPSDs with different specifications for building and upgrading the detectors of neutron scattering instruments at CSNS.Purpose To meet the general requirements specified by the neutron instruments at CSNS,a ^(3)He LPSD was developed and its performances were investigated by using the neutron beam.Methods The neutron beam experiments for this ^(3)He LPSD,including measurements of counting rate plateau curve,position calibration,and position resolution along the tube path,were carried out at the beamline-20 of CSNS.To evaluate its performance in the instrument operation,a detector module made of this ^(3)He LPSD has been installed in the multi-physics instrument(MPI),and the comparison test with the commercial ^(3)He LPSD has been conducted at neutron scattering experiments.Results and conclusion The experimental measurements for this ^(3)He LPSD based on the neutron beam showed that it satisfies the requirements for use in neutron scattering instruments.It reaches a plateau slope of 2.6%/100 V with a plateau range from 1750 to 1950 V and attained a minimal position resolution of 5.3 mm(FWHM),superior to the one achieved by the commercial ^(3)He LPSD.In addition,this ^(3)He LPSD detector module applied to the MPI has been working steadily for half of year and is available for use in experiments.These results provide a sound basis for the subsequent construction and upgradation of the detector of neutron scattering instruments at CSNS.

Tribological and mechanical behaviours of resin-based friction materials based on microcrack filling

To enhance the friction performance of resin-based friction materials,five types of specimens with different polymer ether ketone(PEEK)contents were fabricated and their physiomechanical behaviours were tested and,their tribological properties were investigated using a JF150F-II constant-speed tester.It was found that the addition of PEEK had a positive influence on the properties of the friction materials,and sample FM-3(the shorthand of‘Friction Materials-3’,containing 2 wt%PEEK)exhibited improved friction performance with a fade ratio and recovery ratio of 8.6%and 101.1%respectively.Among all samples,FM-4(the shorthand of‘Friction Materials-4’,con-taining 3 wt%PEEK)had the lowest specific wear rate with a value of 0.622×10^(−7)cm^(3)(N⋅m)^(−1)at 350℃.The PEEK can fill the microcracks in the composite at a high tem-perature and can also cover the hard abrasive particles to prevent them from directly damaging the composite.The findings from this study afford a foundation for studies to further improve the properties of resin-based friction materials.

A machine learning model for textured X-ray scattering and diffraction image denoising

With the advancements in instrumentations of next-generation synchrotron light sources,methodologies for small-angle X-ray scattering(SAXS)/wide-angle X-ray diffraction(WAXD)experiments have dramatically evolved.Such experiments have developed into dynamic and multiscale in situ characterizations,leaving prolonged exposure time as well as radiation-induced damage a serious concern.However,reduction on exposure time or dose may result in noisier images with a lower signal-to-noise ratio,requiring powerful denoising mechanisms for physical information retrieval.Here,we tackle the problem from an algorithmic perspective by proposing a small yet effective machine-learning model for experimental SAXS/WAXD image denoising,allowing more redundancy for exposure time or dose reduction.Compared with classic models developed for natural image scenarios,our model provides a bespoke denoising solution,demonstrating superior performance on highly textured SAXS/WAXD images.The model is versatile and can be applied to denoising in other synchrotron imaging experiments when data volume and image complexity is concerned.

Displacement Calibration of Optical Tweezers With Gravitational Acceleration

In recent years,levitated particles of optical traps in vacuum have shown the enormous potential for precision sensor development and new physics exploration.However,the accuracy of the sensor is still hampered by the uncertainty of the calibration factor relating the detected signal to the absolute displacement of the trapped particle.In this paper,we suggest and experimentally demonstrate a novel calibration method for optical tweezers based on free-falling particles in vacuum,where the gravitational acceleration is introduced as an absolute reference.Our work provides a calibration protocol with a great certainty and traceability,which is significant in improving the accuracy of precision sensing based on levitated optomechanical systems.