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Subject head motion is a major challenge in DWI, leading to image blurring, signal losses, and biases in the estimated diffusion parameters. Here, we investigate a combined application of prospective motion correction and spatial-angular locally low-rank constrained reconstruction to obtain robust, multi-shot, high-resolution diffusion-weighted MRI under substantial motion.Single-shot EPI with retrospective motion correction can mitigate motion artifacts and resolve any mismatching of gradient encoding orientations; however, it is limited by low spatial resolution and image distortions. Multi-shot acquisition strategies could achieve higher resolution and image fidelity but increase the vulnerability to motion artifacts and phase variations related to cardiac pulsations from shot to shot. We use prospective motion correction with optical markerless motion tracking to remove artifacts and reduce image blurring due to bulk motion, combined with locally low-rank regularization to correct for remaining artifacts due to shot-to-shot phase variations.The approach was evaluated on healthy adult volunteers at 3 Tesla under different motion patterns. In multi-shot DWI, image blurring due to motion with 20 mm translations and 30° rotations was successfully removed by prospective motion correction, and aliasing artifacts caused by shot-to-shot phase variations were addressed by locally low-rank regularization. The ability of prospective motion correction to preserve the orientational information in DTI without requiring a reorientation of the b-matrix is highlighted.The described technique is proved to hold valuable potential for mapping brain diffusivity and connectivity at high resolution for studies in subjects/cohorts where motion is common, including neonates, pediatrics, and patients with neurological disorders.

Background A large number of clinical studies based on spontaneous pregnancies (SP) have proved the superiority of non-invasive prenatal testing (NIPT), and whether this technology is suitable for the offspring of assisted reproductive technology (ART) has attracted people's attention. The aim of this study is to evaluate the application value of NIPT in screening for trisomy21(T21), trisomy18(T18), trisomy13(T13) and sex chromosome aneuploidy (SCA) in pregnant women underwent in vitro fertilization (IVF). Results A total of 804 cases (0.88% (804/91280), singleton = 795, twin = 9) of high-risk in the SP group, of the 558 cases (singleton = 556, twin = 2) that underwent invasive prenatal diagnosis (IPD), 343 cases (singleton = 342, twin = 1) were true positive, including 213 cases T21, 28 cases T18, 5 cases T13 and 97 cases (singleton = 96, twin = 1) SCA. The positive predictive value (PPV) of T21, T18, T13 and SCA in singleton pregnancies were 89.12% (213/239), 51.85% (28/54), 21.74% (5/23) and 40.00% (96/240), and the PPV of SCA in twin pregnancies was 100.00%. In the in vitro fertilization (IVF) group, IPD was underwent in 19 cases (singleton = 16, twin = 3) of the 27 cases (0.78% (27/3477), singleton = 16, twin = 3) high-risk, of which 9 cases (singleton = 8, twin = 1) were true positive, including 5 cases (singleton = 4, twin = 1) T21 and 4 cases of SCA. The PPV of singleton T21 and SCA was 66.67% (4/6) and 50.00% (4/8), and the PPV of twin T21 was 100.00% (1/1). There was no significant difference in sensitivity and specificity between the two groups. Based on follow-up, we found 1 case of T21 false negative results in SP group and no false negative case in IVF group. Additionally, the mean fetal fraction (FF) of IVF group was lower than that of SP group (11.23%vs.10.51%, p

Objective To assess the positive predictive value (PPV) of noninvasive prenatal testing (NIPT) as a screening test for sex chromosome aneuploidy (SCA) with different maternal characteristics and prenatal decisions in positive cases. Materials and methods We retrospectively analysed 45,773 singleton pregnancies with different characteristics that were subjected to NIPT in the Maternity and Child Health Hospital of Anhui Province. The results were validated by karyotyping. Clinical data, diagnostic results, and data on pregnancy outcomes were collected. Results In total, 314 cases were SCA positive by NIPT; among those, 143 underwent invasive prenatal diagnostic testing, and 58 were true-positive. Overall, the PPVs for 45,X, 47,XXX, 47,XXY and 47,XYY were 12.5%, 51.72%, 66.67% and 83.33%, respectively. Interestingly, when only pregnant women of advanced maternal age (AMA) were screened, the PPVs for 45,X, 47,XXX, 47,XXY and 47,XYY were 23.81%, 53.33%, 78.95%, and 66.67%, respectively. The frequency of SCA was significantly higher in the AMA group than in the non-AMA group. The frequencies of 47,XXX and 47,XXY were significantly correlated with maternal age. Conclusion NIPT performed better in predicting sex chromosome trisomies than monosomy X, and patients with 45,X positive foetuses were more eager to terminate pregnancy than those with 47,XXX and 47,XYY. AMA may be a risk factor of having a foetus with SCA. Our findings may assist in genetic counselling of AMA pregnant women. Our pre- and posttest counselling are essential for familiarizing pregnant women with the benefits and limitations of NIPT, which may ease their anxiety and enable them to make informed choices for further diagnosis and pregnancy decisions.

Objective To evaluate if the NT value of 2.5 mm ≤ NT Methods A total of 442 fetuses with NT ≥ 2.5 mm were included, in which 241 fetuses underwent karyotype. CMA tests were then carried out when cytogenic analysis showed normal chromosomes and CNV status was compared between 2.5 mm ≤ NT Results Of the 241 fetuses with NT ≥ 2.5 mm, 47(19.50%) were identified by karyotype with chromosomal abnormalities. Among 194 cases with normal karyotype, CMA unraveled additional CNVs in 16(8.25%) cases, including 3(1.55%) pathogenic CNVs, 2(1.03%) likely pathogenic CNVs and 11(5.67%) VOUS. After the subgroup analysis, however, only one case (1.16%) of likely pathogenic was identified by CMA among 86 fetuses with NT between 2.5 mm and 3.0 mm, whereas the rest of 15 CNV cases were all presented in fetuses with NT ≥ 3.0 mm. For the NIPT evaluation, the detection rate of 201 fetuses with isolated increased NT between 2.5 and 3.0 mm was 3.98%, which was indifferent to karyotype with the rate of 5%. In comparison with fetuses with 2.5–3.0 mm combined with other risks, the detection rate of karyotype was 26.92%. Conclusion While no pathogenic CNVs were detected in fetuses, chromosomal aneuploidies and genomic imbalance were found to be the major type of abnormalities when NT was 2.5–3.0 mm. Therefore, our data suggested that CMA should not be recommended when fetuses with an NT value less than 3.0 mm. Instead, NIPT with similar rate of detection as karyotype was recommended for fetuses with isolated increased NT between 2.5 and 3.0 mm.

Accurate estimate of nucleation rate is crucial for the study of ice nucleation and ice-promoting/anti-freeze strategies. Within the framework of Classical Nucleation Theory (CNT), the estimate of ice nucleation rate is very sensitive to thermodynamic parameters, such as chemical potential difference between water and ice $\Delta \mu$ and ice-water interfacial free energy $\gamma$. However, even today, there are still many contradictions and approximations in the estimating of these thermodynamic parameters, introducing large uncertainty to the estimate of the ice nucleation rate. Herein, starting from the basic concepts, for a general solid-liquid crystallization system, we expand the Gibbs-Thomson (GT) equation to second order, and derive the second-order analytical formulas of $\Delta \mu$, $\gamma$ and nucleation barrier $\Delta G$ with combining molecular dynamics (MD) simulations. These formulas describe well the temperature dependence of these thermodynamic parameters. Our results can provide a method of estimating $\Delta \mu$, $\gamma$ and $\Delta G$., Comment: 6 pages, 4 figures

Objective To investigate the clinical value of non-invasive prenatal testing (NIPT) to screen for chromosomal abnormalities in twin pregnancies and to provide further data on NIPT manifestations in twin pregnancies. Materials and methods In a 4-year period, 1048 women with twin pregnancies were voluntarily prospectively tested by NIPT to screen for chromosomal abnormalities by sequencing cell-free foetal DNA (cffDNA) in maternal plasma. Positive NIPT results were confirmed by karyotyping, while negative results were followed up 42 days after delivery. Results Thirteen women had positive NIPT results as follows: 2 cases of trisomy 21 (T21), 1 of trisomy 18 (T18), 7 of sex chromosome aneuploidy (SCA), 1 of microdeletion, and 2 of microduplication. Of these 13 cases, 2 were true-positive cases confirmed by foetal karyotype analysis, namely, 1 case of T21 and 1 of microdeletion. Furthermore, the remaining 11 high-risk pregnant women were confirmed as false positive by foetal karyotyping. Thus, the combined positive predictive value (PPV) of NIPT screening for chromosomal abnormalities in twin pregnancies was 15.4% (2/13). There were no false-negative case via our follow-up results. Conclusion Safe and rapid NIPT has a certain clinical application value; however, the PPV is limited, and the screening efficiency is not stable. Careful use should be made in the screening of chromosomal abnormalities in twin pregnancies.

Objective To assess the detection efficiency of noninvasive prenatal testing (NIPT) for fetal autosomal aneuploidy, sex chromosome aneuploidy (SCA), other chromosome aneuploidy, copy number variation (CNV), and to provide further data for clinical application of NIPT. Materials and methods 25,517 pregnant women who underwent NIPT testing in Anhui Province Maternity and Child Health Hospital from September 2019 to September 2020 were selected, and samples with high-risk test results were subjected to karyotype analysis for comparison by using amniotic fluid, with some samples subjected to further validation by chromosomal microarray analysis, and followed up for pregnancy outcome. Results A total of 25,517 pregnant women who received NIPT, 25,502 cases were tested successfully, and 294 high-risk samples (1.15%) were detected, there were 96 true positive samples, 117 false positive samples and 81 cases were refused further diagnosis. Samples with high risk of autosomal aneuploidy were detected in 71 cases (0.28%), and 51 cases were confirmed, including: trisomy 21 (T21) in 44 cases, trisomy 18 (T18) in 5 cases, and trisomy 13 (T13) in 2 cases; the positive predictive value (PPV) was 91.67%, 45.45%, and 33.33%, respectively, and the negative predictive value was 100%, the false positive rate (FPR) was 0.02%, 0.02%, and 0.02%, respectively.13 samples with high risk of mosaic trisomies 21, 18, and 13 were detected, and 1 case of T21mos was confirmed with a PPV of 8.33%. Samples with high risk of SCA were detected in 72 cases (0.28%), and the diagnosis was confirmed in 23 cases, with a PPV of 41.07% and a FPR of 0.13%. These included 3 cases of 45,X, 6 cases of 47,XXY, 8 cases of 47,XXX and 6 cases of 47,XYY, with PPVs of 12.00%, 50.00%, 72.73%, and 75.00%, respectively, and false-positive rates of 0.09%, 0.02%, 0.01% and 0.01% respectively. Samples with high risk of CNV were detected in 104 cases (0.41%) and confirmed in 18 cases, with a PPV of 32.14% and a FPR of 0.15%. Samples with high risk of other chromosomal aneuploidy were detected in 34 cases (0.13%), and the diagnosis was confirmed in 3 cases, which were T2, T9, and T16 respectively. The overall PPV for other chromosome aneuploidy was 12.50%, with a FPR of 0.08%. Conclusion NIPT is indicated for trisomies 21, 18 and 13 screening, especially for T21. It also has some certain reference value for SCA and CNV, but is not recommended for screening of other chromosomal aneuploidy.

Objective：To explore the efficacy and clinical application value of non-invasive prenatal testing (non-invasive prenatal testing, NIPT) for screening fetal chromosomal abnormalities. Methods: NIPT was performed on 25,517 pregnant women. The high-risk samples were compared with amniotic fluid and cord blood chromosome karyotype analysis. Some samples were further verified by microarray (CMA), and pregnancy outcomes were followed up. Results: Of all the cases examined, 25502 cases were detected successfully, and a total of 294 high-risk samples (1.15%) were detected, of which further diagnosis was made in 208 cases, true positive samples were detected in 96 cases, and further tests were refused in 86 cases.71 cases (0.28%) of autosomal aneuploid high-risk samples were detected and 51 cases were diagnosed, including 44 cases of trisomy 21 (T21), 5 cases of trisomy 18 (T18), and 2 cases of trisomy 13 (T13). The PPV was 90.90%, 45.45% and 33.33%, respectively. Thirteen high-risk samples of trisomy 21, 18, and 13 were detected, and 1 case was confirmed as T21 mosaic PPV was 8.33% NPV was 100%. High-risk samples of sex chromosome aneuploidy (SCA) were detected in 72 cases (0.28%), 23 cases were diagnosed, and the PPV was 40.07%. The PPV was 12.00%, 50.00%, 72.73% and 75.00%, respectively, and the PPV was 12.00%, 50.00%, 72.73% and 75.00%, respectively. High-risk samples of copy number variation (CNV) were detected in 104 cases (0.41%), and 18 cases were diagnosed, with a PPV of 32.14%. Other high-risk samples of chromosome aneuploidy were detected in 34 cases (0.13%), and 3 cases were diagnosed as T2, T9, and T16, respectively. PPV is 8.70%.Conclusion: NIPT is suitable for trisomy 21, 18, and 13 screening, especially for T21. It also has a certain reference value for SCA and microdeletion and microduplication syndromes（MMS）, and it is not recommended for screening for other chromosomal aneuploidies.

Many researchers found high potential of adopting building photovoltaic (PV) systems in urban areas, especially on building rooftop, to improve the sustainability of urban environment. However, the optimal energy output performance and economic benefit of the PV system are affected by the usable roof area, PV array layout, and shading effect considering high city density. This study aims to understand the effects of these design parameters in the urban environment of rooftop PV’s economic performance. This study carries out a case study in the urban area of Melbourne with 90 PV designs under three shading conditions to generate 270 scenarios. Through a lifecycle cost-benefit analysis, including net present value (NPV), NPV per kW, internal return rate (IRR), and payback year, the results can help in developing a comprehensive understanding of the economic performance of rooftop PV designs that cover most of the urban areas of Melbourne. The optimal PV design scenarios for the urban environment are identified, thereby providing investors and industry professionals with useful information on value-for-money PV design. Meanwhile, the maximum shading loss that makes the PV systems financially unfeasible is investigated, and design scenarios with greatest ability to sustain the shading effect are identified. This research can also support the policy makers’ decision on the development and deployment of the roof PV systems in urban planning.

A series of (ZrTi) 1- x (Mg 1/3 Sb 2/3 ) 2 x O 4 (0.04 ≤ x ≤ 0.36) ceramics were successfully synthesized through the conventional solid-state processing. Appropriate content of CuO was added as sintering aids to promote the density of ceramics. The XRD analysis revealed that the main crystalline phase of ceramics sintered at optimal temperature belonged to α-PbO 2 -type structure. Raman spectroscopy and far infrared reflectivity (FIR) spectra were employed to study the phonon modes of ceramics, which explained the relationship between microwave dielectric properties and structure. It is interesting that the τ f are near-zero (+6.6 ~ −4.6 ppm/°C) and meanwhile the Q×f are relatively high (29,000–41,800 GHz) for samples with x in a very wide range of 0.10–0.36. In this range, their dielectric constants (e r ) can be adjustable from 35.4 to 24.4. The results demonstrated this ceramic system is a potential candidate for microwave dielectric applications requiring an adjustable dielectric constants and near zero τ f .

Additional file 1: Supplementary materials

To explore the value of in situ amniocyte culture for prenatal diagnosis.2716 amniotic fluid samples were cultured in situ on slides. After the culture, the slides were stained, photographed and analyzed.All samples were successfully analyzed, with the success rates for primary culture and subculture being 98.42% and 1.58%, respectively. 224 samples (8.25%) were detected with chromosomal aberrations, which included 125 cases with trisomy 21, 31 with trisomy 18, 3 with trisomy 13, 4 with 45,X, 17 with 47,XXY, 5 with 47,XYY, 1 with 48,XXY,+18, 1 with 48,XXYY, 26 with structural chromosomal aberrations, and 11 with mosaicisms for aneuploidies.In situ amniocyte culture is stable and has a high success rate, and is capable of identifying true and false mosaicisms, which can improve the accuracy of prenatal diagnosis.

Phase pure, dense BiFeO3 (BFO) ceramics with average grain sizes of ~ 110 nm, ~ 450 nm, and ~ 1.15 µm were fabricated by spark plasma sintering method. BFO ceramics exhibited grain-size-dependent magnetic properties, which ascribed to the antiferromagnetism–ferromagnetism (AFM–FM) transition. For BFO nanoceramics (~ 110 nm), such transition was much significant, and contributed to a large exchange bias field of HEB = 500 Oe at 5 K. In addition, BFO nanoceramics (~ 110 nm) exhibited lower leakage current and higher resistivity compared to the larger-grained BFO ceramics (~ 450 nm and ~ 1.15 µm). The calculated activation energies (Ea) and X-ray photoelectron spectroscopy analyses revealed the existence of different types of defects in BFO ceramics with different grain sizes.

In order to improve blocking tepmerature of the exchange bias effects in heterojunction composing of ferromagnetic (FM) materials and multiferroic BiFeO3 (BFO). NiFe2O4 (NFO) was selected as the FM material to form FM/BFO heterojunction for its high Curie temperature in this paper. NFO/BFO bilayer film was prepared on Pt/Ti/SiO2/Si substrate via a simple sol-gel spin-coating technique. Exchange bias field at room temperature has been observed as expected and HEB/HC was 4.5%. The M-T curves of the NFO/BFO heterostructure indicated that the magnetic anisotropy disappeared above 300 K. Furthermore, a field-dependent irreversible magnetization behavior and an exponential decay of coercive field and exchange bias field with temperature were found, which suggested a spin-glass-like state existed in the NFO/BFO heterostructure.

Enhanced ferroelectricity and magnetization have been observed in Ti-doped BiFeO 3 nanoceramics prepared using spark plasma sintering processes. X-ray diffraction and FESEM investigations suggested the formation of a pure rhombohedral phase BiFe 0.95 Ti 0.05 O 3 (BFTO) ceramics with an average grain size less than 100 nm. Low dielectric loss and conductivity were attributed to low concentration of Fe 2+ (Fe 3+ /Fe 2+ is 2.8) measured by X-ray photoelectron spectroscopy. The remanent polarization test identified the intrinsic ferroelectricity in BFTO nanoceramics. The piezo-response force microscopy measurements showed nano-scaled ferroelectric domains in BFTO nanoceramics. High remanent magnetization ( M r = 0.1 emu/g) was attributed to the collapse of the cycloidal spin structure for the substitution of Fe 3+ with Ti 4+ and the existence of nanoscaled grains less than the period (62 nm) of the spin cycloid.

Flexible nanocomposites composed of high dielectric constant fillers and polymer matrix have shown great potential for electrostatic capacitors and energy storage applications. To obtain the composited material with high dielectric constant and high breakdown strength, multi-interfacial composited particles, which composed of conductive cores and insulating shells and possessed the internal barrier layer capacitor (IBLC) effect, were adopted as fillers. Thus, Fe3O4@BaTiO3 core-shell particles were prepared and loaded into the poly(vinylidene fluoride-co-hexafluoropropylene) (P(VDF-HFP)) polymer matrix. As the mass fraction of core-shell fillers increased from 2.5 wt % to 30 wt %, the dielectric constant of the films increased, while the loss tangent remained at a low level (

Flexible nanocomposites composed of high dielectric constant fillers and polymer matrix have shown great potential for electrostatic capacitors and energy storage applications. To obtain the composited material with high dielectric constant and high breakdown strength, multi-interfacial composited particles, which composed of conductive cores and insulating shells and possessed the internal barrier layer capacitor (IBLC) effect, were adopted as fillers. Thus, Fe

Congenital cataract is the cloudiness of the eye's natural lens and is a primary cause of congenital vision loss. It accounts for almost 10% of childhood vision loss worldwide.A four generation Chinese family having seven affected individuals was recruited for the current study. Exome sequencing was performed to identify the genetic cause of congenital cataract.Analysis of data identified a novel frameshift mutation, c.608delC (p.A203fs), in theThese findings suggest that p.A203fs is the cause of cataracts in the recruited family. This information would be further helpful in the genetic diagnosis of cataract and in the genetic counseling of similar patients.

Cotton is one of the most important natural fiber crops in the world. Its growth and yield is greatly limited by drought. A quantitative trait locus (QTL) analysis was therefore conducted to investigate the genetic basis of drought tolerance in cotton (Gossypium spp) using 188 F2:3 lines developed from an inter-specific cross between a wild cotton species, G. tomentosum, and an upland cotton, G. hirsutum (CRI-12). A genetic map was constructed using 1295 simple sequence repeat markers, which amplified 1342 loci, distributed on 26 chromosomes, covering 3328.24 cM. A field experiment was conducted in two consecutive years (2014 and 2015) and 11 morphological and physiological traits were recorded under water-limited (W1)/well-watered (W2) regimes at three growth stages (bud, flowering, and full boll). The traits measured included chlorophyll content, plant height, leaf area, leaf number, leaf fresh weight, leaf dry weight, boll weight, number of bolls per plant, and the number of fruiting branches. Sixty-seven and 35 QTLs were found under the W1 and W2 conditions, respectively. Of these, the majority exhibited partial dominance or over-dominance genetic effects for increasing the trait values. Four consistent QTLs were found under the W1 treatment on chromosomes 5, 8, 9, and 16, whereas no consistent QTL was found in W2. Thirteen QTL clusters were also identified on nine chromosomes (2, 3, 5, 6, 9, 14, 15, 16, and 21). These results will help to elucidate the genetic basis of drought tolerance in cotton.

Flexible composited multiferroic films with excellent magnetic-electric effects were prepared. The films were composed of self-assembled CoFe2O4@BaTiO3 core-shell nanoparticle fillers and a poly(vinylidene fluoride-co-hexafluoropropene) matrix. The CoFe2O4@BaTiO3 core-shell particles were prepared using a hydrolysis-hydrothermal method. The surface modification of CoFe2O4 with the cationic surfactant cetyltrimethyl ammonium bromide promoted the BaTiO3 nanocrystals' self-assembly precipitation. Compared with the films loaded by bare CoFe2O4, the films filled with core-shell particles exhibited reduced leakage current density, enhanced dielectric properties, ferroelectric (FE) polarization, and magneto-electric (ME) effects. An excellent ME voltage coefficient of 1835 mV/cm Oe was measured at a DC bias field of −3500 Oe and an AC magnetic field of 3.5 Oe with a frequency of 45 kHz. This enhancement of ME effects was attributed to the large FE-ferromagnetic (FM) interface to volume and the increment of induc...

Trimeric intracellular cation (TRIC) channel subtypes, namely TRIC-A and TRIC-B, are essential counter-ion permeability pathway associated with rapid Ca2+ release from intracellular stores. TRIC-A abundantly expressed in excitable tissues including brain, heart, smooth muscle and skeletal muscle, whereas TRIC-B is ubiquitously expressed throughout tissues. Though TRIC-A-knockout mice are normal in terms of growth, the mice developed hypertension even at young-adult stage. On the other hand, TRIC-B-knockout mice exhibit neonatal lethality due to respiratory failure. Moreover, knockout mice lacking both TRIC channel subtypes exhibit embryonic heart failure, and the mutant cardiomyocytes show compromised ryanodine receptor (RyR)-mediated Ca2+ release. These evidences are indicating that TRIC channel subtypes possess compatible functions in embryonic cardiomyocytes.Because of neonatal lethality occurs in TRIC-B-knockout mice, we examined Ca2+ handling properties in wild-type, TRIC-A-knockout and TRIC-B-knockout neonatal cardiomyocytes. Resting Ca2+ level and Ca2+ transient frequency under isoproterenol treatment were enhanced in TRIC-B-kncokout cardiomyocytes, and caffeine responses under Ca2+-free condition was amplified in both knockout cardiomyocytes.Therefore, TRIC channels are likely to act coordinately on synchronization with Ca2+ release from sarcoplasmic reticulum to maintain normal cardiac function. Furthermore, TRIC-A-knockout mice showed arrhythmia under acutely isoproterenol injection and reduction of Ca2+ spark frequency. Resting Ca2+ level and Ca2+ transient amplitude were augmented in adult TRIC-A-knockout cardiomyocytes. These results seem to support this study.