First Observation of the Decay B_{s}^{0}→K^{-}μ^{+}ν_{μ} and a Measurement of |V_{ub}|/|V_{cb}|

The first observation of the suppressed semileptonic B_{s}^{0}→K^{-}μ^{+}ν_{μ} decay is reported. Using a data sample recorded in pp collisions in 2012 with the LHCb detector, corresponding to an integrated luminosity of 2  fb^{-1}, the branching fraction B(B_{s}^{0}→K^{-}μ^{+}ν_{μ}) is measured to be [1.06±0.05(stat)±0.08(syst)]×10^{-4}, where the first uncertainty is statistical and the second one represents the combined systematic uncertainties. The decay B_{s}^{0}→D_{s}^{-}μ^{+}ν_{μ}, where D_{s}^{-} is reconstructed in the final state K^{+}K^{-}π^{-}, is used as a normalization channel to minimize the experimental systematic uncertainty. Theoretical calculations on the form factors of the B_{s}^{0}→K^{-} and B_{s}^{0}→D_{s}^{-} transitions are employed to determine the ratio of the Cabibbo-Kobayashi-Maskawa matrix elements |V_{ub}|/|V_{cb}| at low and high B_{s}^{0}→K^{-} momentum transfer.

Ultrasound volume projection image quality selection by ranking from convolutional RankNet

Periodic inspection and assessment are important for scoliosis patients. 3D ultrasound imaging has become an important means of scoliosis assessment as it is a real-time, cost-effective and radiation-free imaging technique. With the generation of a 3D ultrasound volume projection spine image using our Scolioscan system, a series of 2D coronal ultrasound images are produced at different depths with different qualities. Selecting a high quality image from these 2D images is the crucial task for further scoliosis measurement. However, adjacent images are similar and difficult to distinguish. To learn the nuances between these images, we propose selecting the best image automatically, based on their quality rankings. Here, the ranking algorithm we use is a pairwise learning-to-ranking network, RankNet. Then, to extract more efficient features of input images and to improve the discriminative ability of the model, we adopt the convolutional neural network as the backbone due to its high power of image exploration. Finally, by inputting the images in pairs into the proposed convolutional RankNet, we can select the best images from each case based on the output ranking orders. The experimental result shows that convolutional RankNet achieves better than 95.5% top-3 accuracy, and we prove that this performance is beyond the experience of a human expert.

SEVEN IN ABSENTIA Ubiquitin Ligases Positively Regulate Defense Against Verticillium dahliae in Gossypium hirsutum

Ubiquitination is a post-translational regulatory mechanism that controls a variety of biological processes in plants. The E3 ligases confer specificity by recognizing target proteins for ubiquitination. Here, we identified SEVEN IN ABSENTIA (SINA) ubiquitin ligases, which belong to the RING-type E3 ligase family, in upland cotton (Gossypium hirsutum). Twenty-four GhSINAs were characterized, and the expression levels of GhSINA7, GhSINA8, and GhSINA9 were upregulated at 24 h after inoculation with Verticillium dahliae. In vitro ubiquitination assays indicated that the three GhSINAs possessed E3 ubiquitin ligase activities. Transient expression in Nicotiana benthamiana leaves showed that they localized to the nucleus. And yeast two-hybrid (Y2H) screening revealed that they could interact with each other. The ectopic overexpression of GhSINA7, GhSINA8, and GhSINA9 independently in Arabidopsis thaliana resulted in increased tolerance to V. dahliae, while individual knockdowns of GhSINA7, GhSINA8, and GhSINA9 compromised cotton resistance to the pathogen. Thus, GhSINA7, GhSINA8, and GhSINA9 act as positive regulators of defense responses against V. dahliae in cotton plants.

Model-Independent Study of Structure in B^{+}→D^{+}D^{-}K^{+} Decays

The only anticipated resonant contributions to B^{+}→D^{+}D^{-}K^{+} decays are charmonium states in the D^{+}D^{-} channel. A model-independent analysis, using LHCb proton-proton collision data taken at center-of-mass energies of sqrt[s]=7, 8, and 13 TeV, corresponding to a total integrated luminosity of 9  fb^{-1}, is carried out to test this hypothesis. The description of the data assuming that resonances only manifest in decays to the D^{+}D^{-} pair is shown to be incomplete. This constitutes evidence for a new contribution to the decay, potentially one or more new charm-strange resonances in the D^{-}K^{+} channel with masses around 2.9  GeV/c^{2}.

Toward High Precision XCO2 Retrievals From TanSat Observations: Retrieval Improvement and Validation Against TCCON Measurements

TanSat is the 1st Chinese carbon dioxide (CO2) measurement satellite, launched in 2016. In this study, the University of Leicester Full Physics (UoL-FP) algorithm is implemented for TanSat nadir mode XCO2 retrievals. We develop a spectrum correction method to reduce the retrieval errors by the online fitting of an 8th order Fourier series. The spectrum-correction model and its a priori parameters are developed by analyzing the solar calibration measurement. This correction provides a significant improvement to the O2 A band retrieval. Accordingly, we extend the previous TanSat single CO2 weak band retrieval to a combined O2 A and CO2 weak band retrieval. A Genetic Algorithm (GA) has been applied to determine the threshold values of post-screening filters. In total, 18.3% of the retrieved data is identified as high quality compared to the original measurements. The same quality control parameters have been used in a footprint independent multiple linear regression bias correction due to the strong correlation with the XCO2 retrieval error. Twenty sites of the Total Column Carbon Observing Network (TCCON) have been selected to validate our new approach for the TanSat XCO2 retrieval. We show that our new approach produces a significant improvement on the XCO2 retrieval accuracy and precision when compared to TCCON with an average bias and RMSE of -0.08 ppm and 1.47 ppm, respectively. The methods used in this study can help to improve the XCO2 retrieval from TanSat and subsequently the Level-2 data production, and hence will be applied in the TanSat operational XCO2 processing.

Observation of Enhanced Double Parton Scattering in Proton-Lead Collisions at sqrt[s_{NN}]=8.16 TeV

A study of prompt charm-hadron pair production in proton-lead collisions at sqrt[s_{NN}]=8.16  TeV is performed using data corresponding to an integrated luminosity of about 30  nb^{-1}, collected with the LHCb experiment. Production cross sections for different pairs of charm hadrons are measured and kinematic correlations between the two charm hadrons are investigated. This is the first measurement of associated production of two charm hadrons in proton-lead collisions. The results confirm the predicted enhancement of double parton scattering production in proton-lead collisions compared to the single parton scattering production.

[Clinical characteristics and pregnancy outcome of 14 pregnant women with history of atherosclerotic cardiovascular disease]

Objective: To summarize the clinical characters and pregnancy outcome in pregnant women with history of atherosclerotic cardiovascular disease (ASCVD). Methods: A total of 14 pregnant women with pre-existing ASCVD admitted to Beijing Anzhen Hospital from October 2013 to May 2020 were enrolled as subjects, whose ASCVD disease status, clinical manifestations, treatment and pregnancy outcomes were collected and retrospectively analyzed. Results: The age of subjects at diagnosis of ASCVD was (31±7) years old. The main intervention before pregnancy was revascularization (10 cases), and the rest 4 cases were treated with medicine. The age of subjects at pregnancy was (36±5) years old. A total of 12 cases had risk factors of ASCVD. In early stages of pregnancy, there were 1 case with cardiac function level Ⅲ and 1 with cardiac function level Ⅳ. Abnormal ventricular wall motion and ventricular aneurysm formation were determined in 3 cases by echocardiography, one of which was complicated with moderate left ventricular ejection fraction impairment. Abnormal ST segment in 4 cases and sinus tachycardia in 1 case were found by electrocardiogram. Troponin (TNI) increased in 1 case. The serum low density lipoprotein cholesterol level (LDL-C) of these pregnant women at early stages of pregnancy was (2.3±1.0) mmol/L. A total of 9 pregnant women entered later stages of pregnancy, 1 of whom had chest tightness after slight activity. There were 4 cases with excessive weight gain and 2 cases with insufficient weight gain during pregnancy, and there were 1 case with cardiac function level Ⅲ and 1 case with mild impaired left heart function. The average level of LDL-C was (2.6±0.6) mmol/L in 5 pregnant women at their later stages of pregnancy. The main treat measures included anti-platelet therapy (aspirin, 75-100 mg/d) and healthy lifestyle interventions. Five pregnant women terminated their pregnancy at the early stage of pregnancy, and 9 full-term pregnant women underwent hysterotomy with intraoperative blood loss of 180-800 ml. Adverse cardiac events occurred in 2 cases and gestational diabetes was diagnosed in 3 cases during pregnancy, among which 2 cases were complicated with chronic hypertension and preeclampsia. The weight of 9 live newborns was (3 102±647) g, among which 2 were smaller than gestational age and 1 was of low birth weight. Conclusions: Women with established ASCVD before preynancy have risk of adverse cardiac events in pregnancy. Strengthening the management of high risk factors in pregnancy is conducive to achieving a good pregnancy outcome.

Research Progress on MicroRNA in Forensic Medicine as Molecular Markers

Abstract

MicroRNA （miRNA） belongs to a class of endogenous non-coding small RNA molecules with a length of 18-24 nucleotides. The expression of miRNA is highly conservative, has time sequence and is highly tissue-specific. MiRNA could not be easily degraded by ribonuclease, and is resistant to changes in environmental factors such as temperature and pH value. Moreover, miRNA can even be detected in corrupt tissue. As a result, miRNA has broad application prospects in many fields of forensic medicine such as source identification of body fluid and estimation of cause of death. This article briefly summarizes the application of miRNA in forensic practice, such as body fluid identification, determination of postmortem interval and cause of death analysis.

Identification and application of the Pigm-1 gene in rice disease resistance breeding

Rice blast, caused by Magnaporthe oryzae, is one of the most destructive diseases of rice worldwide. The identification and utilization of resistance genes are crucial and significant for breeding resistant rice cultivars. We identified a resistance gene from Shuangkang77009, which is highly resistant to the rice blast isolate Guy11 using map-based cloning. We performed bulked segregant analysis combined with specific length amplified fragment sequencing. We also performed association analysis, candidate gene prediction and cDNA sequencing to identify the candidate gene. The resistance gene is located on chromosome 6, and we ultimately mapped the resistance locus to a 92-kb region. The resistance gene in Shuangkang77009 was allelic to PigmR, hereafter referred to as Pigm-1. The Pigm-1 protein had one amino acid change: serine (Ser) residue 860 was replaced by tyrosine (Tyr) in Pigm-1 compared with the previously identified Pigm protein, which significantly changed the structure of the Pigm-1 protein based on 3-D structure simulation. In addition, using the developed molecular marker linked to the Pigm-1 gene and molecular marker-assisted selection technology, we introduced the Pigm-1 gene into Minghui86, a widely used and excellent restorer. We generated 11 stable homozygous rice lines with desirable agronomic traits and strong resistance to rice blast. In conclusion, Pigm-1, a natural allelic variant of PigmR, was responsible for blast resistance in Shuangkang77009 rice. The molecular marker-assisted breeding strategy for Pigm-1 was highly efficient.

Nomogram predicting early neurological improvement in ischaemic stroke patients treated with endovascular thrombectomy

BACKGROUND AND PURPOSE

Early neurological improvement (ENI) after endovascular thrombectomy (EVT) has been associated with favorable outcomes. This study aimed to identify the optimal definition of ENI and develop a nomogram for predicting ENI after EVT in acute ischaemic stroke.

METHODS

Patients with EVT were enrolled from a multicenter registry as the training cohort. The receiver operating characteristic curve was used to estimate the optimal threshold for ENI at 24 h of EVT. Logistic regression analysis was utilized to generate the best-fit nomogram for predicting ENI. The discrimination of the nomogram was assessed using the area under the receiver operating characteristic curve (AUC). An additional 447 patients from two stroke centers were prospectively recruited as the test cohort for validating the nomogram.

RESULTS

A total of 612 patients with EVT were included in the training cohort. The optimal threshold for predicting 3-month favorable outcome (modified Rankin Scale 0-2) was an improvement of the National Institutes of Health Stroke Scale (NIHSS) score by ≥6 points (AUC 0.875; sensitivity 79.5%; specificity 90.7%). Age, blood glucose, recanalization, symptomatic intracranial hemorrhage (sICH) and baseline Alberta Stroke Program Early Computed Tomography Score (ASPECTS) were independently associated with ENI, and were incorporated in the nomogram. The AUC of the nomogram was 0.795 in the training cohort and 0.752 in the test cohort.

CONCLUSIONS

A reduction of NIHSS score ≥6 appeared to be the optimal definition of ENI. The nomogram composed of age, blood glucose, recanalization, sICH and baseline ASPECTS may predict the probability of ENI in ischaemic stroke patients treated with EVT.

TATDN1 promotes the development and progression of breast cancer by targeting microRNA-140-3p

OBJECTIVE

To explore whether long non-coding RNA (lncRNA) TATDN1 can promote the proliferation and cell cycle progression of breast cancer cells by adsorbing microRNA-140-3p, thus participating in the development of breast cancer (BCa).

PATIENTS AND METHODS

Expressions of TATDN1 and microRNA-140-3p in BCa tissues and paracancerous tissues were determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Meanwhile, TATDN1 expression in BCa cell lines was detected as well. Regulatory effects of TATDN1 and microRNA-140-3p on proliferation and cell cycle progression of BCa cells were evaluated by Cell Counting Kit-8 (CCK-8) and flow cytometry, respectively. The binding relationship of microRNA-140-3p to NOVA1 and TATDN1 was examined by dual-luciferase reporter gene assay. Finally, rescue experiments were conducted to explore whether TATDN1 can regulate NOVA1 expression by adsorbing microRNA-140-3p to exert its biological function in BCa.

RESULTS

TATDN1 was highly expressed in BCa tissues and cell lines. Upregulation of TATDN1 promoted the proliferative potential and cell cycle progression of MCF-7 and MDA-MB-231 cells. Dual-luciferase reporter gene assay indicated that TATDN1 could bind to microRNA-140-3p, which was lowly expressed in BCa. Overexpression of microRNA-140-3p inhibited the proliferative potential and cell cycle progression of MCF-7 and MDA-MB-231 cells. Moreover, microRNA-140-3p partially inhibited the role of TATDN1 in regulating cellular behaviors of BCa cells. NOVA1 was predicted to be the target gene of microRNA-140-3p. Overexpression of NOVA1 partially abolished the inhibitory effects of microRNA-140-3p on proliferation and cell cycle progression of MCF-7 and MDA-MB-231 cells.

CONCLUSIONS

TATDN1 promotes the proliferative potential and cell cycle progression of BCa cells through adsorbing microRNA-140-3p to upregulate NOVA1 expression.

Dexmedetomidine attenuates myocardial ischemia/reperfusion injury through regulating lactate signaling cascade in mice

OBJECTIVE

The aim of this study was to investigate the role of dexmedetomidine (Dex) in lactate signaling cascade and myocardial ischemia/reperfusion (I/R) injury in mice.

MATERIALS AND METHODS

The left anterior descending of the coronary artery was ligatured for 30 min and then reperfused for 6 h to induce myocardial I/R injury in mice. Heart samples were collected and the levels of lactate, SOD and MDA were measured. Infarct size and myocardium were stained with triphenyltetrazolium chloride and TUNEL, respectively. In addition, the expression levels of MCT1, cytochrome c, cleaved caspase-9 and -3 were detected by Western blot.

RESULTS

The myocardial infarct size, lactate and MDA levels of the I/R group were significantly increased, whereas the SOD activity was decreased. However, Dex significantly reduced the myocardial infarct size, as well as lactate and MDA levels in contrast to the I/R group. Meanwhile, the SOD activity was remarkably increased. The expression levels of MCT1, cytochrome c, cleaved caspase-9 and -3 were significantly increased in the I/R group. In addition, Dex administration further increased the expression of MCT1, whereas decreased the expressions of cytochrome c, cleaved caspase-9 and -3 in contrast to the I/R group.

CONCLUSIONS

Dex elevated the expression of mitochondrial MCT1 and inhibited oxidative stress and the activation of mitochondria-dependent apoptosis in mice. This indicated that Dex attenuated myocardial I/R injury by regulating lactate signaling cascade.

Four Theories of the Madden-Julian Oscillation

Studies of the Madden-Julian Oscillation (MJO) have progressed considerably during the past decades in observations, numerical modeling, and theoretical understanding. Many theoretical attempts have been made to identify the most essential processes responsible for the existence of the MJO. Criteria are proposed to separate a hypothesis from a theory (based on the first principles with quantitative and testable assumptions, able to predict quantitatively the fundamental scales and eastward propagation of the MJO). Four MJO theories are selected to be summarized and compared in this article: the skeleton theory, moisture-mode theory, gravity-wave theory, and trio-interaction theory of the MJO. These four MJO theories are distinct from each other in their key assumptions, parameterized processes, and, particularly, selection mechanisms for the zonal spatial scale, time scale, and eastward propagation of the MJO. The comparison of the four theories and more recent development in MJO dynamical approaches lead to a realization that theoretical thinking of the MJO is diverse and understanding of MJO dynamics needs to be further advanced.

Genome-wide association study reveals the genetic basis of fiber quality traits in upland cotton (Gossypium hirsutum L.)

BACKGROUND

Fiber quality is an important economic trait of cotton, and its improvement is a major goal of cotton breeding. To better understand the genetic mechanisms responsible for fiber quality traits, we conducted a genome-wide association study to identify and mine fiber-quality-related quantitative trait loci (QTLs) and genes.

RESULTS

In total, 42 single nucleotide polymorphisms (SNPs) and 31 QTLs were identified as being significantly associated with five fiber quality traits. Twenty-five QTLs were identified in previous studies, and six novel QTLs were firstly identified in this study. In the QTL regions, 822 genes were identified and divided into four clusters based on their expression profiles. We also identified two pleiotropic SNPs. The SNP locus i52359Gb was associated with fiber elongation, strength, length and uniformity, while i11316Gh was associated with fiber strength and length. Moreover, these two SNPs were nonsynonymous and located in genes Gh_D09G2376 and Gh_D06G1908, respectively. RT-qPCR analysis revealed that these two genes were preferentially expressed at one or more stages of cotton fiber development, which was consistent with the RNA-seq data. Thus, Gh_D09G2376 and Gh_D06G1908 may be involved in fiber developmental processes.

CONCLUSIONS

The findings of this study provide insights into the genetic bases of fiber quality traits, and the identified QTLs or genes may be applicable in cotton breeding to improve fiber quality.