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The interannual relationship between the quasi‐biennial oscillation (QBO) and the South China Sea (SCS) summer monsoon intensity (SCSSMI) is investigated using the ERA5 data set in the period of 1953–2020. The QBO–SCSSMI connection is weak in El Niño‐Southern Oscillation (ENSO)‐related summer, but significant in neutral ENSO summer. In neutral ENSO summer, there is significant positive correlation between QBO and SCSSMI, that is, the SCSSMI is enhanced in the QBO westerly phase, while it is weakened in the QBO easterly phase with larger amplitude of the SCSSMI anomaly. QBO may modulate the SCSSMI in three possible ways. The QBO‐related temperature anomalies downward to the lower stratosphere directly affect the SCS monsoon convection by modulating the upper‐tropospheric stability and tropopause height over the SCS region. Moreover, the QBO‐related anomalous zonal wind downward to the lower stratosphere may regulate cross‐tropopause vertical wind shear and then modulate the convection development. Besides, the QBO‐related zonal wind and temperature signals propagating downward into the upper troposphere can affect the horizontal divergence by influencing the vertical vorticity and the geopotential via thermal forcing. Through those three processes, QBO directly affects the deep convection activities and then modulates the SCSSMI via internal dynamic adjustment. In the southern SCS, cross‐tropopause vertical wind shear makes a main contribution to deep convections, while upper‐tropospheric static stability makes a major contribution to deep convection in the northern SCS. The conclusions are also generally verified by the CMIP6 model simulation. [ABSTRACT FROM AUTHOR]

Manure is a leading source of methane (CH4), nitrous oxide (N2O), and ammonia (NH3) emissions, and alternative manure management practices can help society meet climate goals and mitigate air pollution. Recent studies show that biochar‐composting can substantially reduce emissions from manure. However, most studies test only one type of biochar applied at a single application rate, leading to high variation in emission reductions between studies. Here, we measured greenhouse gas and NH3 emissions during biochar‐composting of dairy manure with biochar applied at 5% or 20%, by mass, and made from walnut shells, almond shells, or almond clippings. We found little difference in emissions between biochar type. However, we found that the 20% application rates increased CH4 emissions and decreased N2O and NH3 emissions, resulting in a net reduction in global warming potential (GWP). We attribute this result to biochar increasing the formation of compost aggregates, which likely acted as anaerobic reactors for methanogenesis and complete denitrification. Biochar may have further fueled CH4 production and N2O consumption by acting as an electron shuttle within aggregates. We recommend lower application rates, as we found that the 5% treatments in our study led to a similar reduction in GWP without increasing CH4 emissions. [ABSTRACT FROM AUTHOR]

Cardiac hypertrophy often refers to the abnormal growth of heart muscle through a variety of factors. The mechanisms of cardiomyocyte hypertrophy have been extensively investigated using neonatal rat cardiomyocytes treated with phenylephrine. a-Enolase is a glycolytic enzyme with 'multifunctional jobs' beyond its catalytic activity. Its possible contribution to cardiac dysfunction remains to be determined. The present study aimed to investigate the change of a-enolase during cardiac hypertrophy and explore its role in this pathological process. We revealed that mRNA and protein levels of a-enolase were significantly upregulated in hypertrophic rat heart induced by abdominal aortic constriction and in phenylephrine-treated neonatal rat cardiomyocytes. Furthermore, knockdown of [alpha]-enolase by RNA interference in cardiomyocytes mimicked the hypertrophic responses and aggravated phenylephrine-induced hypertrophy without reducing the total glycolytic activity of enolase. In addition, knockdown of [alpha]-enolase led to an increase of GATA4 expression in the normal and phenylephrine-treated cardiomyocytes. Our results suggest that the elevation of [alpha]-enolase during cardiac hypertrophy is compensatory. It exerts a catalytic independent role in protecting cardiomyocytes against pathological hypertrophy. Key words: [alpha]-enolase, cardiac hypertrophy, phenylephrine, glycolysis, GATA4. L'hypertrophie cardiaque correspond souvent a la croissance anormale de muscle cardiaque par l'intermediaire de divers facteurs. Les modes d'action de l'hypertrophie des cardiomyocytes ont ete etudies en detail a l'aide de cardiomyocytes neonataux de rat exposes a la phenylephrine. L'[alpha] enolase est un enzyme glycolytique avec des actions multiples au-dela de son activite catalytique. Sa contribution eventuelle au dysfonctionnement cardiaque demeure toutefois a etablir. Les presents travaux visaient a etudier la modification de l'[alpha] enolase au cours de l'hypertrophie cardiaque, ainsi que son role dans ce processus pathologique. Nous avons montre que l'expression de l'[alpha] enolase en matiere de proteines et d'ARNm etait regulee a la hausse de facon marquee dans le coeur de rat dont l'hypertrophie etait provoquee par la striction de l'aorte abdominale et dans les cardiomyocytes neonataux de rats exposes a la phenylephrine. En outre, le << knock-down >> de l'[alpha] enolase par interference contre l'ARN dans les cardiomyocytes mimait les reactions d'hypertrophie et aggravait l'hypertrophie provoquee par la phenylephrine, et ce, sans entrainer de diminution de l'activite glycolytique totale de l'enolase. De plus, le knock-down de l'[alpha] enolase a mene a une augmentation de l'expression de GATA4 dans les cardiomyocytes normaux et exposes a la phenylephrine. Nos resultats laissent entendre que la hausse des taux d'a enolase pendant l'hypertrophie cardiaque ferait partie d'un mode d'action compensatoire. Elle jouerait un role catalytique independant dans la protection des cardiomyocytes contre l'hypertrophie pathologique. [Traduit par la Redaction] Mots-cles : [alpha]-enolase, hypertrophie cardiaque, phenylephrine, glycolyse, GATA4., Introduction Cardiac hypertrophy is a response of the heart to a variety of physiological or pathological stimuli, including exercise, pressure or volume overload, and neurohumoral disorders. It may initially be [...]

Abstract Diabetic kidney disease (DKD) is a serious complication of hyperglycemia. Currently, there is no effective therapeutic intervention for DKD. In this study, we sought to provide a set of gene profile in diabetic kidneys. We identified 338 genes altered in diabetes-induced DKD glomeruli, and PLK2 exhibited the most dramatic change. Gene set enrichment analysis (GSEA) indicated multiple signaling pathways are involved DKD pathogenesis. Here, we investigated whether PLK2 contributes to podocyte dysfunction, a characteristic change in the development of DKD. High D-glucose (HDG) significantly increased PLK2 expression in mouse podocytes. Suppressing PLK2 attenuated HDG-induced apoptosis and inflammatory responses both in vitro and in vivo. NAC, an antioxidant reagent, rescued HDG and PLK2 overexpression-induced kidney injuries. In summary, we demonstrated that silencing PLK2 attenuates HDG-induced podocyte apoptosis and inflammation, which may serve as a future therapeutic target in DKD.

Background: Multiparametric MRI radiomics could distinguish human epidermal growth factor receptor 2 (HER2)‐positive from HER2‐negative breast cancers. However, its value for further distinguishing HER2‐low from HER2‐negative breast cancers has not been investigated. Purpose: To investigate whether multiparametric MRI‐based radiomics can distinguish HER2‐positive from HER2‐negative breast cancers (task 1) and HER2‐low from HER2‐negative breast cancers (task 2). Study Type: Retrospective. Population: Task 1: 310 operable breast cancer patients from center 1 (97 HER2‐positive and 213 HER2‐negative); task 2: 213 HER2‐negative patients (108 HER2‐low and 105 HER2‐zero); 59 patients from center 2 (16 HER2‐positive, 27 HER2‐low and 16 HER2‐zero) for external validation. Field Strength/Sequence: A 3.0 T/T1‐weighted contrast‐enhanced imaging (T1CE), diffusion‐weighted imaging (DWI)‐derived apparent diffusion coefficient (ADC). Assessment: Patients in center 1 were assigned to a training and internal validation cohort at a 2:1 ratio. Intratumoral and peritumoral features were extracted from T1CE and ADC. After dimensionality reduction, the radiomics signatures (RS) of two tasks were developed using features from T1CE (RS‐T1CE), ADC (RS‐ADC) alone and T1CE + ADC combination (RS‐Com). Statistical Tests: Mann–Whitney U tests, the least absolute shrinkage and selection operator, receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA). Results: For task 1, RS‐ADC yielded higher area under the ROC curve (AUC) in the training, internal, and external validation of 0.767/0.725/0.746 than RS‐T1CE (AUC = 0.733/0.674/0.641). For task 2, RS‐T1CE yielded higher AUC of 0.765/0.755/0.678 than RS‐ADC (AUC = 0.706/0.608/0.630). For both of task 1 and task 2, RS‐Com achieved the best performance with AUC of 0.793/0.778/0.760 and 0.820/0.776/0.711, respectively, and obtained higher clinical benefit in DCA compared with RS‐T1CE and RS‐ADC. The calibration curves of all RS demonstrated a good fitness. Data Conclusion: Multiparametric MRI radiomics could noninvasively and robustly distinguish HER2‐positive from HER2‐negative breast cancers and further distinguish HER2‐low from HER2‐negative breast cancers. Evidence Level: 3. Technical Efficacy: Stage 2. [ABSTRACT FROM AUTHOR]

Background: Synthetic MRI (syMRI) has enabled quantification of multiple relaxation parameters (T1/T2 relaxation time [T1/T2], proton density [PD]), and their longitudinal change during neoadjuvant chemotherapy (NAC) promises to be valuable parameters for treatment response evaluation in breast cancer. Purpose: To investigate the time course changes of syMRI parameters during NAC and evaluate their value as predictors for pathological complete response (pCR) in breast cancer. Study Type: Retrospective, longitudinal. Population: A total of 129 women (median age, 50 years; range, 28–69 years) with locally advanced breast cancer who underwent NAC; all performed multiple conventional breast MRI examinations with added syMRI during NAC. Field Strength/Sequence: A 3.0 T, T1‐weighted dynamic contrast enhanced and syMRI acquired by a multiple‐dynamic, multiple‐echo sequence. Assessment: Breast MRI was set at four time‐points: baseline, after one cycle, after three or four cycles of NAC and preoperation. SyMRI parameters and tumor diameters were measured and their changes from baseline were calculated. All parameters were compared between pCR and non‐pCR. Interaction between syMRI parameters and clinicopathological features was analyzed. Statistical Tests: Mann–Whitney U tests, random effects model of repeated measurement, receiver operating characteristic (ROC) analysis, interaction analysis. Results: Median synthetic T1/T2/PD and tumor diameter generally decreased throughout NAC. Absolute T1 at early‐NAC, T1, and PD at mid‐NAC were significantly lower in the pCR group. After early‐NAC, the T1 change was significantly higher in the pCR (median ± IQR, 18.17 ± 11.33) than the non‐pCR group (median ± IQR, 10.90 ± 10.03), with the highest area under the ROC curves (AUC) of 0.769 (95% CI, 0.684–0.838). Interaction analysis showed that histological grade III patients had higher odds ratio (OR) (OR = 1.206) compared to grade II patients (OR = 1.067). Data Conclusion: Synthetic T1 changes after one cycle of NAC maybe useful for early evaluating NAC response in breast cancer during whole treatment cycles. However, its discriminative ability is significantly affected by histological grade. Evidence Level: 4 Technical Efficacy: Stage 2. [ABSTRACT FROM AUTHOR]

A metal-free method for the dual activation of aryl phosphinate has been developed; the P–H and P–O bonds are sequentially activated by the Tf2O/DMSO system. Without the requirement of metals and unstable P-reagents, this one-pot procedure provides a convenient and practical access to a variety of aryl phosphonates. A mechanism involving twice generation of electrophilic P-species and two SN-processes is proposed on the basis of the control experiments. [ABSTRACT FROM AUTHOR]

Finding feasible solutions for sustainable food production is challenging. Here we try to understand the balance between crop productivity and ecological stewardship using agroecological‐based soil management strategies. We evaluated the potential of different organic materials such as dairy manure compost and different biochar manure co‐composts, derived locally from agricultural wastes, to enhance soil ecosystem services. We assessed their potential impact on soil moisture and nutrient retention, greenhouse gas emissions, and crop productivity using data collected from an outdoor tomato column study. Results from the experiment showed potential of biochar co‐composts to positively affect soil health by lessening loss of essential nutrients such as NO3−‐N and NH4+‐N, sustained tomato yield, and uphold crop water use efficiency. However, yield response to soil organic amendment is constrained by external factors such as irrigation strategies, with treatments under deficit irrigation greatly impacted. Overall, we observed a positive effect of adding biochar manure co‐composts to soil, although best management practices are needed to optimize crop productivity and avoid unintentional consequences. Core Ideas: Effects of different biochar manure co‐composts on soil ecosystem services and tomato productivity were evaluated.A 75% deficit irrigation rate was also imposed on soil treatments.Organic amendment exhibits higher nitrogen retention potential and sustained crop yield with minimal effect on water use efficiency.Plant physiological response to water stress overshadows response to soil organic amendments.Biochar‐dairy manure co‐composts are a superior soil amendment compared to manure compost alone. [ABSTRACT FROM AUTHOR]