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In zoophilous plants, floral orientation evolved under both biotic and abiotic pressure to enhance pollination success. However, the adaptive significance of horizontal orientation in radially symmetrical (actinomorphic) flowers remains largely unknown, although that of bilaterally symmetrical flowers has been well studied. We experimentally altered floral angle in a population of insect-pollinated Platycodon grandiflorus flowers to examine the effects of floral orientation on pollinator behaviour, pollination success and pollen rain damage avoidance. To further investigate the potential pollen damage by rain, we obtained past precipitation records for the study area during the flowering season, and experimentally tested P. grandiflorus pollen damage by water. Horizontally oriented flowers received more pollinator visits and had pollen grains on the stigma in male and/or female phases than downward- and/or upward-oriented flowers and avoided pollen damage by rainfall better than upward-oriented flowers. A pollen germination experiment showed that approximately 30% of pollen grains burst in distilled water, indicating that pollen damage by rainfall may be significant in P. grandiflorus. Our field experiments revealed that upward-oriented flowers cannot avoid pollen damage by rainfall during the flowering period, and that both upward- and downward-oriented flowers experience pollinator limitation in female success. Therefore, horizontal flower orientation appears to be adaptive in this insect-pollinated actinomorphic species that blooms during the rainy season.

Background Delayed door-to-balloon (DTB) time and deterioration of in-hospital mortality during the coronavirus disease 2019 (COVID-19) pandemic have been reported. Little is known about the impact of changes in in-hospital medical management before primary percutaneous coronary intervention (PCI) for COVID-19 such as screening test (antigen or polymerase chain reaction (PCR) tests, chest CT for excluding the pneumoniae) and primary PCI under full personal protective equipment (PPE) on DTB time and in-hospital mortality. Purpose The purpose of this study was to evaluate the impact of in-hospital medical management for COVID-19 on DTB time and in-hospital mortality during COVID-19 pandemic period. Methods We compared DTB time and in-hospital mortality of 502 ST-elevation myocardial infarction (STEMI) patients during COVID-19 pandemic (February 2020 and January 2021) with 2035 STEMI patients before pandemic (February 2016 and January 2020) using date from Mie ACS registry, a retrospective and multicenter registry. Results The COVID-19 screening tests before primary PCI and/or primary PCI under full PPE was performed on 173/502 (34.5%) patients (antigen or PCR tests; 39 (7.8%), chest CT; 156 (31.3%), full PPE; 11 (2.2%)). These patients had lower rate of achievement of DTB time ≤90 min compared with others (Figure 1A). Moreover, In-hospital management of COVID-19 screening tests and/or primary PCI under full PPE was an independent factor of DTB time>90 min with odds ratio of 1.94 (95% confidential interval: 1.37–2.76, p Conclusion In-hospital medical management for COVID-19 screening tests before primary PCI and/or primary PCI under full PPE was the independent factor of DTB time>90 min. This study reinforces the need to focus efforts on shortening DTB time, while controlling the epidemic of infection. Funding Acknowledgement Type of funding sources: None.

The mechanical strength of a plant stem (a load-bearing organ) helps the plant resist drooping, buckling and fracturing. We previously proposed a method for quickly evaluating the stiffness of an inflorescence stem in the model plant Arabidopsis thaliana based on measuring its natural frequency in a free-vibration test. However, the relationship between the stiffness and flexural rigidity of inflorescence stems was unclear. Here, we compared our previously described free-vibration test with the three-point bending test, the most popular method for calculating the flexural rigidity of A. thaliana stems, and examined the extent to which the results were correlated. Finally, to expand the application range, we present an example of a modified free-vibration test. Our results provide a reference for improving estimates of the flexural rigidity of A. thaliana inflorescence stems.

Phytoparasitic nematodes parasitize many species of rooting plants to take up nutrients, thus causing severe growth defects in the host plants. During infection, root-knot nematodes induce the formation of a characteristic hyperplastic structure called a root-knot or gall on the roots of host plants. Although many previous studies addressed this abnormal morphogenesis, the underlying mechanisms remain uncharacterized. To analyze the plant-microorganism interaction at the molecular level, we established an in vitro infection assay system using the nematode Meloidogyne incognita and the model plant Arabidopsis thaliana. Time-course mRNA-seq analyses indicated the increased levels of procambium-associated genes in the galls, suggesting that vascular stem cells play important roles in the gall formation. Conversely, genes involved in the formation of secondary cell walls were decreased in galls. A neutral sugar analysis indicated that the level of xylan, which is one of the major secondary cell wall components, was dramatically reduced in the galls. These observations were consistent with the hypothesis of a decrease in the number of highly differentiated cells and an increase in the density of undifferentiated cells lead to gall formation. Our findings suggest that phytoparasitic nematodes modulate the developmental mechanisms of the host to modify various aspects of plant physiological processes and establish a feeding site.

The cortical motor cells (CMCs) in a legume pulvinus execute the reversible deformation in leaf movement that is driven by changes in turgor pressure. In contrast to the underlying osmotic regulation proper, the cell wall structure of CMCs that contributes to the movement has yet to be characterized in detail. Here, we report that the cell wall of CMCs has circumferential slits with low levels of cellulose deposition. This structure is unique and distinct from that of any other primary cell walls reported so far; thus, we named them “pulvinar slits.” Notably, we predominantly detected de-methyl-esterified homogalacturonan inside pulvinar slits, with a low deposition of highly methyl-esterified homogalacturonan, as with cellulose. In addition, Fourier-transform infrared spectroscopy analysis indicated that the cell wall composition of pulvini is different from that of other axial organs, such as petioles or stems. Moreover, monosaccharide analysis showed that pulvini are pectin-rich organs like developing stems and that the amount of galacturonic acid in pulvini is greater than in developing stems. Computer modeling suggested that pulvinar slits facilitate anisotropic extension in the direction perpendicular to the slits in the presence of turgor pressure. When tissue slices of CMCs were transferred to different extracellular osmotic conditions, pulvinar slits altered their opening width, indicating their deformability. In this study, we thus characterized a distinctive cell wall structure of CMCs, adding new knowledge to repetitive and reversible organ deformation as well as the structural diversity and function of the plant cell wall.

Wood fibers form thick secondary cell wall (SCW) in xylem tissues to give mechanical support to trees. NAC SECONDARY WALL THICKENING PROMOTING FACTOR3/SECONDARY WALL-ASSOCIATED NAC DOMAIN PROTEIN 1 (NST3/SND1) and NST1 were identified as master regulators of SCW formation in xylem fiber cells in the model plant Arabidopsis thaliana. In Populus species, four NST/SND orthologs have been conserved and coordinately control SCW formation in wood fibers and phloem fibers. However, it remains to be elucidated whether SCW formation in other xylem cells, such as ray parenchyma cells and vessel elements, is regulated by NST/SND orthologs in poplar. We knocked out all NST/SND genes in hybrid aspen using the clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 nuclease (Cas9) system and investigated the detailed histological appearance of stem tissues in the knockout mutants. Observation by light microscopy and transmission electron microscopy showed that SCW was severely suppressed in wood fibers, phloem fibers and xylem ray parenchyma cells in the knockout mutants. Although almost all wood fibers lacked SCW, some fiber cells formed thick cell walls. The irregularly cell wall-forming fibers retained primary wall and SCW, and were mainly located in the vicinity of vessel elements. Field emission-scanning electron microscope observation showed that there were no apparent differences in the structural features of pits such as the shape and size between irregularly SCW-forming wood fibers in the knockout mutants and normal wood fibers in wild-type. Cell wall components such as cellulose, hemicellulose and lignin were deposited in the cell wall of irregularly SCW-forming wood fibers in quadruple mutants. Our results indicate that four NST/SND orthologs are master switches for SCW formation in wood fibers, xylem ray parenchyma cells and phloem fibers in poplar, while SCW is still formed in limited wood fibers, which are located at the region adjacent to vessel elements in the knockout mutants.

Arabidopsis thaliana transcription factors belonging to the ERFIIId and ERFIIIe subclade (ERFIIId/e) of the APETALA 2/ethylene response factor (AP2/ERF) family enhance primary cell wall (PCW) formation. These transcription factors activate expression of genes encoding PCW-type cellulose synthase (CESA) subunits and other genes for PCW biosynthesis. In this study, we show that fiber-specific expression of ERF035-VP16 and ERF041-VP16, which are VP16-fused proteins of ERFIIId/e members, promote cell wall thickening in a wild-type background with a concomitant increase of alcohol insoluble residues (cell wall content) per fresh weight (FW) and monosaccharides related to the PCW without affecting plant growth. Furthermore, in the ERF041-VP16 lines, the total amount of lignin and the syringyl (S)/guaiacyl (G) ratio decreased, and the enzymatic saccharification yield of glucose from cellulose per fresh weight improved. In these lines, PCW-type CESA genes were upregulated and ferulate 5-hydropxylase1 (F5H1), which is necessary for production of the S unit lignin, was downregulated. In addition, various changes in the expression levels of transcription factors regulating secondary cell wall (SCW) formation were observed. In conclusion, fiber cell-specific ERF041-VP16 improves biomass yield, increases PCW components, and alters lignin composition and deposition and may be suitable for use in future molecular breeding programs of biomass crops.

Recently, many researches on autostereoscopic displays have been carried out. In this work, we propose a new display configuration using the Pepper's ghost effect and a dynamic image adjustment method for a large scale autostereoscopic display. We also propose a method for extending the number of viewpoints for simultaneous viewing by multiple people. In the experiment, after constructing the device, we acquired the light transport matrix using two cameras and dynamically adjusted the video images. We observed parallax in the adjusted images, and we confirmed that the images were stereoscopic. At present, only one person can view the stereoscopic images at the same time because only two parallax images are presented. However, when acquiring the light transport matrix, we can create the video from multiple viewpoints by increasing the number of cameras. In the future, we will experiment using three cameras and confirm that the three-dimensional image presentation is possible by three parallaxes.

Background Evaluation of two-dimensional (2D) speckle-tracking longitudinal strain (LS) is useful for assessing global and regional left ventricular (LV) dysfunction. Purpose The purpose of this study was to test the hypothesis that temporal changes in regional 2D-LS distribution, (i.e., changes in area and intensity of the negative strain), during the systolic period may reflect the LV activation sequence. Methods We studied 52 patients with an ejection fraction Results In patients with LBBB, negative strain appeared initially in the septum region. Then, the contracted area enlarged including the apical region, and the basal lateral region contracted late. On the other hand, Narrow QRS showed a few regional differences in strain at the end of QRS (standard deviation in 17-segments: Narrow QRS 1.3±0.4%*, LBBB 3.3±1.1%, RVP 3.2±1.0%, LVP 3.3±1.1%, *p Conclusion The 2D-LS distribution during the systolic period reflects the LV contraction process in patients with an altered ventricular activation sequence, and may have potential for identifying the regions of early activation site and subsequent activation propagation. Funding Acknowledgement Type of funding source: None

Background During the chemical and biochemical decomposition of lignocellulosic biomasses, lignin is highly recalcitrant. Genetic transformation of plants to qualitatively and/or quantitatively modify lignin may reduce these recalcitrant properties. Efficient discovery of genes to achieve lignin manipulation is thus required. Results To screen for new genes to reduce lignin recalcitrance, we heterologously expressed 50 enzymatic genes under the control of a cinnamate 4-hydroxylase (C4H) gene promoter, derived from a hybrid aspen, which is preferentially active in tissues with lignified cell walls in Arabidopsis plants. These genes encode enzymes that act on metabolites in shikimate, general phenylpropanoid, flavonoid, or monolignol biosynthetic pathways. Among these genes, 30, 18, and 2 originated from plants, bacteria, and fungi, respectively. In our first screening step, 296 independent transgenic plants (T1 generation) harboring single or multiple transgenes were generated from pools of seven Agrobacterium strains used for conventional floral-dip transformation. Wiesner and Mäule staining patterns in the stems of the resultant plants revealed seven and nine plants with apparent abnormalities in the two respective staining analyses. According to genomic PCR and subsequent direct sequencing, each of these 16 plants possessed a gene encoding either coniferaldehyde dehydrogenase (calB), feruloyl-CoA 6′-hydroxylase (F6H1), hydroxycinnamoyl-CoA hydratase/lyase (couA), or ferulate 5-hydroxylase (F5H), with one transgenic plant carrying both calB and F6H1. The effects of these genes on lignin manipulation were confirmed in individually re-created T1 transgenic Arabidopsis plants. While no difference in lignin content was detected in the transgenic lines compared with the wild type, lignin monomeric composition was changed in the transgenic lines. The observed compositional change in the transgenic plants carrying calB, couA, and F5H led to improved sugar release from cell walls after alkaline pretreatment. Conclusions Simple colorimetric characterization of stem lignin is useful for simultaneous screening of many genes with the potential to reduce lignin recalcitrance. In addition to F5H, the positive control, we identified three enzyme-coding genes that can function as genetic tools for lignin manipulation. Two of these genes (calB and couA) accelerate sugar release from transgenic lignocelluloses.

Plastid ribosome biogenesis is important for plant growth and development. REGULATOR OF FATTY ACID COMPOSITION3 (RFC3) is a member of the bacterial ribosomal protein S6 family and is important for lateral root development. rfc3-2 dramatically reduces the plastid rRNA level and produces lateral roots that lack stem cells. In this study, we isolated a suppressor of rfc three2 (sprt2) mutant that enabled recovery of most rfc3 mutant phenotypes, including abnormal primary and lateral root development and reduced plastid rRNA level. Northern blotting showed that immature and mature plastid rRNA levels were reduced, with the exception of an early 23S rRNA intermediate, in rfc3-2 mutants. These changes were recovered in rfc3-2 sprt2-1 mutants, but a second defect in the processing of 16S rRNA appeared in this line. The results suggest that rfc3 mutants may be defective in at least two steps of plastid rRNA processing, one of which is specifically affected by the sprt2-1 mutation. sprt2-1 mutants had a mutation in CRM FAMILY MEMBER 3b (CFM3b), which encodes a plastid-localized splicing factor. A bimolecular fluorescence complementation (BiFC) assay suggested that RFC3 and SPRT2/CFM3b interact with each other in plastids. These results suggest that RFC3 suppresses the nonspecific action of SPRT2/CFM3b and improves the accuracy of plastid rRNA processing.

Purpose Whereas fenestration at Fontan operation was reported to be effective for smooth initiation to Fontan circulation, subsequently developed aortopulmonary collateral arteries under the presence of remaining hypoxia were a matter of concern.So as our institutional policy, it is closed as much and early as possible (temporary fenestration). This study aimed to reveal long-term outcomes for patients at riskswho underwent Fontan operation with temporary fenestration. Methods Of 107 patients undergoing Fontan operation from 1995 to 2004, 79 patients (73.8%) were free from any risks (NR group) and 28 patients (26.2%) had risks for Fontan operation (R group). Hypoplastic left heart syndrome, heterotaxy syndrome with obstructive total anomalous of pulmonary venous connection, and individual cases with high preoperative pulmonary artery pressure (PAP), systemic ventricular end diastolic pressure (SVEDP) or low ejection fraction (SVEF) were defined as a risk for Fontan completion.Age at Fontan operation was older in R group (6.6 vs 2.3years-old, p = 0.0004). Preoperative PAP (12.8 vs 11.3mmHg, p = 0.03) and SVEDP (8.8 vs 7.1mmHg, p = 0.02) were higher and SVEF (53.7 vs 60.0%, p = 0.002) was lower in R group. Pulmonary vascular resistance (PVR) was not different. Fenestration was created in all patients in R group, then it was closed at the mean duration of 2.9 years after Fontan operation. Results Freedom from death or protein-losing enteropathy rate at 5, 10, and 15 years after Fontan operation were 97, 96, and 93% in NR group and 96, 93, and 86% in R group (log-rank: p = 0.20). Fifty-one patients (64.6%) in NR group and 17 patients (60.7%) in R group underwent serial catheter examinations at 5, 10, and 15 years after Fontan operation and exercise capacity testing at 15 years after Fontan operation (Figure). In R group, arterial oxygen saturation was lower and PVR was higher even after close of fenestration (Figure). In addition, 12 patients (71%) in R group developed significant veno-venous collaterals, which were defined by more than 3mm in diameter of collateral veins or a condition where pulmonary veins were contrasted in venography. On the contrary, cardiac index (CI), SVEDP, and PAP were not different and no significant difference on peak oxygen uptake and anaerobic threshold were observed between in 2 groups. Conclusions Although the mild cyanosis remained due to the development of veno-venous collaterals after the closure of temporary fenestration, CI, SVEDP and PAP well maintained in patients at risk for Fontan operation. These results might to lead acceptable life prognosis and freedom fromprotein-losing enteropathy rate for patients at risk for Fontan operation. Abstract P37 Figure

We investigated the effects of Zn additions on the mechanical properties and microstructure of Mg–1.2Al–0.5Ca–0.4Mn and Mg–1.2Al–0.5Ca–0.4Mn–1.6Zn (wt%) alloy sheets fabricated by twin-roll casting and conventional hot rolling. The room temperature stretch formability of the solution-treated alloy sheet is improved by the addition of Zn. The Mg–1.2Al–0.5Ca–0.4Mn–1.6Zn alloy shows an excellent stretch formability with the larger Index Erichsen value of 8.2 mm due to a weak transverse direction split texture. The development of the weak texture is attributed to the uniform grain growth by the solute segregation to the recrystallized grain boundaries. Subsequent bake-hardening treatment, 2% pre-strain at 170 °C for 20 min leads to substantial increase in strength without the loss of ductility. The bake-hardened Mg–1.2Al–0.5Ca–0.4Mn–1.6Zn alloy exhibits a high tensile yield strength of 235 MPa with an elongation to failure of 27.1%.

The bulk of a plant's biomass, termed secondary cell walls, accumulates in woody xylem tissues and is largely recalcitrant to biochemical degradation and saccharification1. By contrast, primary cell walls, which are chemically distinct, flexible and generally unlignified2, are easier to deconstruct. Thus, engineering certain primary wall characteristics into xylem secondary walls would be interesting to readily exploit biomass for industrial processing. Here, we demonstrated that by expressing AP2/ERF transcription factors from group IIId and IIIe in xylem fibre cells of mutants lacking secondary walls, we could generate plants with thickened cell wall characteristics of primary cell walls in the place of secondary cell walls. These unique, newly formed walls displayed physicochemical and ultrastructural features consistent with primary walls and had gene expression profiles illustrative of primary wall synthesis. These data indicate that the group IIId and IIIe AP2/ERFs are transcription factors regulating primary cell wall deposition and could form the foundation for exchanging one cell wall type for another in plants.

The WUSCHEL-RELATED HOMEOBOX1 (WOX1) transcription factor and its homolog PRESSED FLOWER (PRS) are multifunctional regulators of leaf development that act as transcriptional repressors. These genes promote cell proliferation under certain conditions, but the related molecular mechanisms are not well understood. Here, we present a new function for WOX1 in cell proliferation. To identify the WOX1 downstream genes, we performed a microarray analysis of shoot apices of transgenic Arabidopsis thaliana lines harboring [35Sp::WOX1-glucocorticoid receptor (GR)] in which the WOX1 function was temporarily enhanced by dexamethasone. The downregulated genes were significantly enriched for the Gene Ontology term “response to auxin stimulus”, whereas the significantly upregulated genes contained auxin transport-associated PIN1 and AUX1 and the auxin response factor MP, which are involved in formation of auxin response maxima. Simultaneous treatments of synthetic auxin and dexamethasone induced the formation of green compact calli and the unorganized proliferation of cells in the hypocotyl. A microarray analysis of 35Sp::WOX1-GR plants treated with indole-3-acetic acid and dexamethasone revealed that WOX1 and auxin additively influenced their common downstream genes. Furthermore, in the presence of an auxin-transport inhibitor, cell proliferation during leaf initiation was suppressed in the prs mutant but induced in a broad region of the peripheral zone of the shoot apical meristem in the ectopic WOX1-expressing line FILp::WOX1. Thus, our results clarify the additive effect of WOX1/PRS and auxin on their common downstream genes and highlight the importance of the balance between their functions in controlling cell proliferation.

Plastid ribosome biogenesis is important for plant growth and development. REGULATOR OF FATTY ACID COMPOSITION3 (RFC3) is a member of the bacterial ribosomal protein S6 family and is important for lateral root development. rfc3-2 dramatically reduces the plastid rRNA level and produces lateral roots that lack stem cells. In this study, we isolated a suppressor of rfc three2 (sprt2) mutant that enabled recovery of most rfc3 mutant phenotypes, including abnormal primary and lateral root development and reduced plastid rRNA level. Northern blotting showed that immature and mature plastid rRNA levels were reduced, with the exception of an early 23S rRNA intermediate, in rfc3-2 mutants. These changes were recovered in rfc3-2 sprt2-1 mutants, but a second defect in the processing of 16S rRNA appeared in this line. The results suggest that rfc3 mutants may be defective in at least two steps of plastid rRNA processing, one of which is specifically affected by the sprt2-1 mutation. sprt2-1 mutants had a mutation in CRM FAMILY MEMBER 3b (CFM3b), which encodes a plastid-localized splicing factor. A bimolecular fluorescence complementation (BiFC) assay suggested that RFC3 and SPRT2/CFM3b interact with each other in plastids. These results suggest that RFC3 suppresses the nonspecific action of SPRT2/CFM3b and improves the accuracy of plastid rRNA processing.

The plastid evolved from a symbiotic cyanobacterial ancestor and is an essential organelle for plant life, but its developmental roles in roots have been largely overlooked. Here, we show that plastid translation is connected to the stem cell patterning in lateral root primordia. The RFC3 gene encodes a plastid-localized protein that is a conserved bacterial ribosomal protein S6 of β/γ proteobacterial origin. The rfc3 mutant developed lateral roots with disrupted stem cell patterning and associated with decreased leaf photosynthetic activity, reduced accumulation of plastid rRNAs in roots, altered root plastid gene expression, and changes in expression of several root stem cell regulators. These results suggest that deficiencies in plastid function affect lateral root stem cells. Treatment with the plastid translation inhibitor spectinomycin phenocopied the defective stem cell patterning in lateral roots and altered plastid gene expression observed in the rfc3 mutant. Additionally, when prps17 defective in a plastid ribosomal protein was treated with low concentrations of spectinomycin, it also phenocopied the lateral root phenotypes of rfc3. The spectinomycin treatment and rfc3 mutation also negatively affected symplasmic connectivity between primary root and lateral root primordia. This study highlights previously unrecognized functions of plastid translation in the stem cell patterning in lateral roots., Summary: Successful plastid gene expression is required for stem cell patterning in lateral root primordia as revealed by genetic and pharmacological impairment of plastid translation.