Maize smart-canopy architecture enhances yield at high densities.

Increasing planting density is a key strategy to enhance maize yields1-3. An ideotype for dense planting requires a 'smart canopy' with leaf angles at different canopy layers differentially optimized to maximize light interception and photosynthesis4-6, amongst other features. Here, we identified leaf angle architecture of smart canopy 1 (lac1), a natural mutant possessing upright upper leaves, less erect middle leaves and relatively flat lower leaves. lac1 has improved photosynthetic capacity and weakened shade-avoidance responses under dense planting. lac1 encodes a brassinosteroid C-22 hydroxylase that predominantly regulates upper leaf angle. Phytochrome A photoreceptors accumulate in shade and interact with the transcription factor RAVL1 to promote its degradation via the 26S proteasome, thereby attenuating RAVL1 activation of lac1 and reducing brassinosteroid levels. This ultimately decreases upper leaf angle in dense fields. Large-scale field trials demonstrate lac1 boosts maize yields under high densities. To quickly introduce lac1 into breeding germplasm, we transformed a haploid inducer and recovered homozygous lac1 edits from 20 diverse inbred lines. The tested doubled haploids uniformly acquired smart-canopy-like plant architecture. We provide an important target and an accelerated strategy for developing high-density-tolerant cultivars, with lac1 serving as a genetic chassis for further engineering of a smart canopy in maize.

Feasibility study of on-line monitoring gadolinium based on neutron induced gamma activation.

Gadolinium is a soluble neutron poison for ensuring criticality safety of nuclear facility. A neutron induced gamma activation device was developed for the on-line measurement of gadolinium. The experimental device consisted of an 241Am-Be neutron source, six 3He detectors and a liquid scintillation detector. The size of sample container was optimized by using Monte Carlo simulations. Aqueous sample containing gadolinium nitrate were conducted with the device to obtain the calibration curve, and neutron self-shielding effect was also studied to correct the non-linear response. The results showed the minimum detectable concentration (MDC) of gadolinium was 0.426 mg/L. Two test samples were conducted to evaluate the performance of the device. The results demonstrated that the discrepancies were within 10%, which indicate the developed system can be successfully used for on-line monitoring of gadolinium.

Fluctuations in resource availability shape the competitive balance among non-native plant species.

Fluctuating resource availability plays a critical role in determining non-native plant invasions through mediating the competitive balance between non-native and native species. However, the impact of fluctuating resource availability on interactions among non-native species remains largely unknown. This represents a barrier to understanding invasion mechanisms, particularly in habitats that harbor multiple non-native species with different responses to fluctuating resource availability. To examine the responses of non-native plant species to nutrient fluctuations, we compared the growth of each of 12 non-native species found to be common in local natural areas to nutrients supplied at a constant rate or supplied as a single large pulse in a pot experiment. We found that seven species produced more biomass with pulsed nutrients compared to constant nutrients (hereafter "benefitting species"), while the other five species did not differ between nutrient enrichment treatments (hereafter "non-benefitting species"). To investigate how nutrient fluctuations influence the interactions among non-native plant species, we established experimental non-native communities in the field with two benefitting and two non-benefitting non-native species. Compared with constant nutrient supply, the single large pulse of nutrient did not influence community biomass, but strongly increased the biomass and cover of the benefitting species and decreased those of the non-benefitting species. Furthermore, the benefitting species had higher leaf N content and greater plant height when nutrients were supplied as a single large pulse than at a constant rate, whereas the non-benefitting species showed no differences in leaf N content and were shorter when nutrients were supplied as a single large pulse than at a constant rate. Our results add to the growing evidence that the individual responses of non-native species to nutrient fluctuation are species-specific. More importantly, benefitting species were favored by nutrients coming in a pulse, while non-benefitting ones were favored by nutrients coming constantly when they grew together. This suggests that nutrient fluctuations can mediate the competitive balance among non-native plants and may thus determine their invasion success in a community harboring multiple non-native plant species.

Management of Migrated or Residual Stones Following Laparoscopic Pyelolithotomy and Ureterolithotomy in Abnormal Kidneys: A Prospective and Randomized Comparison.

Objective: To conduct a prospective and randomized controlled trial comparing contemporaneous transabdominal rigid ureteroscopy (TRU) with postoperative extracorporeal shockwave lithotripsy (SWL) in the management of migrated or residual stones during laparoscopic pyelolithotomy and ureterolithotomy in kidneys with either intrinsic or extrinsic abnormalities. Materials and Methods: From February 2016 to December 2019, 45 patients with migrated or residual stones following laparoscopic pyelolithotomy and ureterolithotomy were accrued and randomly divided into two groups. These patients all had either urinary tract obstruction distal to the stone or concomitant ipsilateral intrinsic or extrinsic pathology requiring laparoscopic intervention. Twenty-three patients underwent contemporaneous TRU, and 22 patients underwent postoperative SWL. Patients' demographics, perioperative variables, and follow-up data were collected. The primary outcome was the final stone-free rate (SFR) at the 2-month follow-up. Secondary outcomes included blood loss, operative time, change in serum creatinine, complications per Clavien-Dindo grading system, renal colic occurrence rate (RCOR), and postoperative hospitalization. Results: There was no significant difference in gender, age, body mass index, location, or stone burden between the two groups (p > 0.05). At the 2-month follow-ups, the SFR was higher in the TRU than the SWL group (p = 0.002), and the RCOR was lower in the TRU than the SWL group (p = 0.005). Postoperative hospitalization was also shorter for the TRU group. No significant difference was noted in the operative time, blood loss, change in serum creatinine, or perioperative complications (p > 0.05). Conclusion: Contemporaneous TRU is more effective and equally safe compared to postoperative SWL in the management of residual or migrated stones during laparoscopic pyelolithotomy and ureterolithotomy in kidneys with either intrinsic or extrinsic abnormalities.

Teosinte ligule allele narrows plant architecture and enhances high-density maize yields.

Increased planting densities have boosted maize yields. Upright plant architecture facilitates dense planting. Here, we cloned UPA1 (Upright Plant Architecture1) and UPA2, two quantitative trait loci conferring upright plant architecture. UPA2 is controlled by a two-base sequence polymorphism regulating the expression of a B3-domain transcription factor (ZmRAVL1) located 9.5 kilobases downstream. UPA2 exhibits differential binding by DRL1 (DROOPING LEAF1), and DRL1 physically interacts with LG1 (LIGULELESS1) and represses LG1 activation of ZmRAVL1 ZmRAVL1 regulates brd1 (brassinosteroid C-6 oxidase1), which underlies UPA1, altering endogenous brassinosteroid content and leaf angle. The UPA2 allele that reduces leaf angle originated from teosinte, the wild ancestor of maize, and has been lost during maize domestication. Introgressing the wild UPA2 allele into modern hybrids and editing ZmRAVL1 enhance high-density maize yields.

miR302a inhibits the proliferation of esophageal cancer cells through the MAPK and PI3K/Akt signaling pathways.

MicroRNAs (miRNAs/miRs) are involved in the regulation of various types of cancer, either as oncogenes or tumor suppressors. miR302a has been reported that it could suppress tumor cell proliferation by inhibiting Akt in prostate cancer. The present study examined the effect of miR302a on proliferation and invasion in esophageal cancer cell lines. The expression levels of miR302a in esophageal cancer cell lines was determined by reverse transcription-polymerase chain reaction. Subsequently, miR302a mimics were transfected into esophageal cancer cells, and cell viability and invasion were assessed by MTT and Transwell assays. In addition, the effects of miR302a on the mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling pathways were investigated by western blot analysis. The results revealed that miR302a expression was significantly decreased in the esophageal cancer cell lines compared with a healthy esophagus epithelium cell line. Upregulation of miR302a inhibited the proliferation and invasion of esophageal cancer cells, and decreased the phosphorylation of extracellular signal-regulated kinase 1/2 and Akt. Taken together, the results of the present study indicated that miR302a overexpression inhibited the proliferation and invasion of esophageal cancer cells through suppression of the MAPK and PI3K/Akt signaling pathways, indicating the potential value of miR302a as a treatment target for human esophageal cancer.

[Association between the polymorphisms of cluster of differentiation 14 gene promoters and the susceptibility of multiple organ dysfunction syndrome after severe chest trauma].

OBJECTIVE: To investigate the polymorphisms of cluster of differentiation 14(CD14)gene promoters and explore whether such polymorphisms are associated with the susceptibility to multiple organ dysfunction syndrome(MODS) in Chongqing population. METHODS: The single nucleotide polymorphisms of the promoter region of CD14 gene at position -1145 and -159 were detected using polymerase chain reaction-restriction fragment length polymorphism method in 106 patients with severe chest trauma, among whom 47 were with MODS. RESULTS: Trauma patients carrying G allele tended to have a higher risk of MODS than those carrying A allele at position-1145, the MODS scores in trauma patients carrying G allele were significantly higher than those carrying A allele (P=0.217 for dominant effect and P=0.037 for recessive effect), and the MODS scores in trauma patients carrying T allele were significantly higher than those carrying C allele at position -159 (P=0.048 for dominant effect and P=0.198 for recessive effect). The genotypes of CD14 gene at positions -1145 and -159 were significantly correlated with the MODS scores (P=0.043,P=0.046). Compare with single-point mutation, simultaneous two-point mutation had significantly higher risk of MODS (Pü0.01), while the difference of MODS scores showed no statistical significance (P=0.239). CONCLUSION: The polymorphisms of CD14 gene promoters are associated with MODS after severe chest trauma in Chongqing population.