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In thin film deposition, Ar/SiH4 mixtures are widely used to make polysilicon (poly-Si) and hydrogenated amorphous silicon (a-SiH) layers. Despite extensive research conducted on this mixture, little research has focused on the variations in plasma properties, radicals, and ions that occur during plasma discharge in inductively coupled plasma (ICP) equipment compared to capacitive coupled plasma equipment. In this paper, we investigate the properties of the plasma generated through mathematical modeling of Ar/SiH4 inductive coupled plasma discharge by using the electron energy distribution function (EEDF) obtained by solving the Boltzmann equation. We closely examine the variation in plasma properties and the correlation of plasma variables by controlling the radio frequency power and gas pressure during the process conditions. The Boltzmann equation was computed by assuming the two-term approximation, resulting in a Druyvesteyn-like EEDF due to the high-pressure conditions. To validate the simulation model, the 2D simulation results were compared with probe measurements performed in a two-turn ICP chamber. The results demonstrated encouraging agreement with the measured data. This research not only enhances our comprehension of the discharge characteristics but also establishes a framework for optimizing the discharge conditions to enhance the process and effectively regulate external variables. [ABSTRACT FROM AUTHOR]

Herein, we investigated the effect of a dielectric film on the transmission spectrum of a bar-type flat cutoff probe (BCP). By conducting electromagnetic wave simulations, we found that placing a dielectric film with a thickness of 1 mm or less on the sensor did not affect the measurement of the BCP under thin sheath condition. However, a film thickness of 1 mm or more results in a low-frequency shift in the cutoff frequency. The shift in the cutoff frequency was related not only to the film thickness, but also to the dielectric constant of the film and sheath width, which could be understood through a circuit model of the BCP. The calculated results were experimentally validated using alumina plates of various thicknesses. Consequently, our findings demonstrate that measuring the electron density on a BCP is feasible even when a dielectric film is deposited, thereby improving the accuracy of the measurement. [ABSTRACT FROM AUTHOR]

Real-time monitoring of plasma parameters at the wafer plane is important because it significantly affects the processing results, yield enhancement, and device integrity of plasma processing. Various plasma diagnostic sensors, including those embedded in a chamber wall and on-wafer sensors, such as flat-cutoff sensors, have been developed for plasma measurements. However, to measure the plasma density on the wafer surface in real-time when processing plasma with bias power, such as in the semiconductor etching process, one must analyze the transmission spectrum of the flat-cutoff sensor in an environment with bias power applied. In this study, the transmission-spectrum and measured plasma-density characteristics of an electrode-embedded flat-cutoff sensor are analyzed via electromagnetic simulations and experiments under applied bias power. Our findings indicate that the flat-cutoff sensor accurately measures the plasma density, which is equivalent to the input plasma density under low bias power. Conversely, under high bias power, the plasma density measured by the sensor is lower than the input plasma density. Also, a thick-sheath layer is formed owing to the high bias power, which may complicate the measurement of plasma parameters using the flat-cutoff sensor. Plasma diagnostics using a flat-cutoff sensor in thick-sheath environments can be achieved by optimizing the flat-cutoff sensor structure. Our findings can enhance the analysis of plasma parameters on-wafer surfaces in processing environments with bias power applied. [ABSTRACT FROM AUTHOR]

In the era of big data, negative differential resistance (NDR) devices have attracted significant attention as a means of handling massive amounts of information. While 2D materials have been used to achieve NDR behavior, their intrinsic material characteristics have produced limited performance improvements. In this article, a facile phase modification method is presented via a plasma‐assisted sulfidation process to synthesize multiphased WS2 thin films, including distorted 1 T (D‐1 T) phase and 2 H phases for photoreactive NDR devices with p‐Si. The D‐1 T phase offers a feasible route to achieve high‐performance NDR devices with excellent stability and semimetallic properties. A comprehensive investigation of experimental and computational analyses elucidates the phase transition mechanism with various temperatures and electrical properties of D‐1 T WS2. In addition, optimizing electron tunneling in the multiple‐phased tungsten disulfide (MP‐WS2)/p‐Si heterojunction at MP‐WS2 with 77.4% D‐1 T phase results in superior NDR performance with a peak‐to‐valley current ratio of 13.8 and reliable photoreactive random‐access memory. This unique phase engineering process via plasma‐assisted sulfidation provides a pioneering perspective in functionalization and reliability for next‐generation nanoelectronics. [ABSTRACT FROM AUTHOR]

To address long-standing gender inequity in the workplace, scholars and practitioners have called for men to enact ally work to better support and advocate for women at work. Integrating prior research on allyship with positive organizational scholarship, we propose an enrichment-based perspective on allyship that suggests that male allyship is a mechanism by which male privilege awareness translates into relational well-being at work. We theorize that the relational benefits of male allyship could offset the previously studied costs of engaging in allyship at work. While past research has highlighted barriers to men's involvement in gender-parity initiatives, we find that men can mobilize social support by engaging in intergroup helping behaviors at work. Using a sample of male supervisors in the United States, Study 1 finds that male privilege awareness has a positive impact on male allyship at work. In addition, Study 2 shows that male allyship mediates the relationship between male privilege awareness and men's relational well-being at work. All in all, our study shows that men can reap relational benefits following their enactment of allyship and that male privilege awareness is an important antecedent in this process. We discuss the theoretical and practical implications of our findings. Public Significance Statement: Taking an enrichment-based perspective on allyship, our study shows that male allyship guided by privilege awareness leads to men's relational well-being at work. When men introspect about their privilege, they not only help their female colleagues but also help themselves by reaping relational benefits: They experience heightened belongingness at work and receive greater support from colleagues. [ABSTRACT FROM AUTHOR]

In the industrial semiconductor plasma processing, plasma density and its spatial distribution are critical for the understanding of discharge physics and the enhancement of the processing yield via monitoring of the status of plasma processing. Thus, real-time monitoring of plasma density and uniformity in the wafer region during wafer processing have been receiving significant attention. In this study, we developed an electrode-embedded flat-cutoff array sensor for the real-time measurement of electron density uniformity during wafer processing. We measured the spatial distribution of electron density on the wafer surface, compared it with the results measured in the bulk plasma region, and found different plasma distributions between the two where this difference can be attributed to local electron kinetics. We also performed plasma etching of amorphous carbon materials, which showed a clear correlation with the electron density distribution measured by the flat-cutoff array sensor. This indicates that the electron density distribution on the wafer surface is crucial for the process result. Thus, the array sensor developed in this study can be applied not only to measure plasma uniformity but also to predict the wafer process beforehand, making it highly significant for industrial plasma processing methods, such as virtual metrology. [ABSTRACT FROM AUTHOR]

Atomic layer etching (ALE), a cyclic process of surface modification and removal of the modified layer, is an emerging damage-less etching technology for semiconductor fabrication with a feature size of less than 10 nm. Among the plasma sources, inductively coupled plasma (ICP) can be a candidate for ALE, but there is a lack of research linking discharge physics to the ALE process. In this study, we comprehensively investigated the discharge physics of ICPs with a radio frequency (RF) bias and Ar/C4F6 mixture to be considered for the ALE process. Detailed studies on the discharge physics were conducted in each step of ALE (i.e., modification step, removal step) as well as the whole cycle as follows: (1) In the general ALE cycle, plasma properties dependent on the chamber geometry and the discharge mode of the ICP were analyzed; (2) in the modification step, a plasma instability with molecular gas was observed. The timescale for molecular gas removal was also investigated; (3) in the removal step, changes in plasma characteristics with the RF bias power were studied. Based on measurements of these plasma physical parameters, the discharge condition for ALE was optimized. ALE was performed on various thin films, including a-Si, poly c-Si, SiO2, and Si3N4. For each thin film, thicknesses of 0.5–2.0 nm were etched per cycle, as in quasi-ALE. Finally, ALE was performed on a patterned wafer, and the etch thickness of 0.6 nm per cycle and fine etch profile were obtained. [ABSTRACT FROM AUTHOR]

Fatty acids (FAs) are important desirable compounds in oil crops. Here, we evaluated the amounts of 14 FAs in sesame grains using gas chromatography mass spectrometry and investigated the effects of genotype and environment on FA composition in 2 years. Unsaturated FA fractions accounted for 80.018% of the total FAs in sesame in 2014 and 78.936% in 2015. C16:1 and C20:1 levels exhibited few effects from the environment, while other FAs were affected significantly by environmental variance. C18:1 and C24:0 were significantly correlated with population structure. We also identified 249 QTLs that were strongly associated with the amounts of 14 FAs in sesame. These findings will be useful for understanding FA metabolism in sesame and for improving the quality of sesame through molecular breeding in the future. [ABSTRACT FROM AUTHOR]

Purpose. This study aimed to evaluate the statuses of P16INK4A expression and human papillomavirus (HPV) infection among patients with penile cancer at a single Korean institution. Patients and Methods. Fourteen patients with penile cancer at our center were retrospectively identified and their clinicopathological data were analyzed. The patients' HPV and P16INK4A expression status (a known tumor suppressor protein) were tested using genotyping with a DNA chip assay and immunohistochemical staining, respectively. The results regarding HPV status were compared to those from another Asian study. Results. The mean age at diagnosis was 60 years (range: 34–86 years). The median tumor size was 3.0 cm (range: 0.6–4.7 cm). Ten tumors were located on the penile glans. Five patients tested positive for HPV DNA (5/14, 36%) and all cases involved HPV type 16 (5/5, 100%). Positive expression of P16INK4A was observed in 6 cases (6/14, 43%). Among the HPV positive cases, 80% of cases (4/5) were also positive for P16INK4A. The prevalence of HPV infection in our study (36%) was higher than in a previous Asian study (23%). Conclusions. This is the first study to evaluate the prevalence of HPV infection and P16INK4A expression among patients with penile cancer at a single Korean institution. The prevalence of HPV (36%) was slightly higher than the results from a previous Asian study. Additional multi-center studies are needed to better understand penile cancer in Korea and to identify biomarkers that can determine high-risk cases and predict their prognosis. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Proanthocyanidins are oligomeric or polymeric end products of flavonoid metabolic pathways starting with the central phenylpropanoid pathway. Although soybean (Glycine spp.) seeds represent a major source of nutrients for the human diet, as well as components for the cosmetics industry as a result of their high levels of flavonoid metabolites, including isoflavonoids, anthocyanins and proanthocyanidins, the genetic regulatory mechanisms underlying proanthocyanidin biosynthesis in soybean remain unclear. RESULTS: We evaluated interspecific and intraspecific variability in flavonoid components in soybean using 43 cultivars, landraces and wild soybean accessions. We performed transcriptomic profiling of genes encoding enzymes involved in flavonoid biosynthesis using three soybean genotypes, Hwangkeum (elite cultivar), IT109098 (landrace) and IT182932 (wild accession), in seeds. We identified a Glycine max landrace, IT109098, with a proanthocyanidin content as high as that of wild soybean. Different homologous genes for anthocyanidin reductase, which is involved in proanthocyanidin biosynthesis, were detected as differentially expressed genes between IT109098 and IT182932 compared to Hwangkeum. CONCLUSION: We detected major differences in the transcriptional levels of genes involved in the biosynthesis of proanthocyanidin and anthocyanin among genotypes beginning at the early stage of seed development. The results of the present study provide insights into the underlying genetic variation in proanthocyanidin biosynthesis among soybean genotypes. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the prognosis of pT3a upstaging from cT1 renal cell carcinoma, and to compare the outcomes of partial or radical nephrectomy in cases of pT3a upstaging. Materials and Methods: We reviewed the records of patients who underwent partial or radical nephrectomy for cT1 at our center between January 2001 and October 2013. We compared the 2-year recurrence-free survivals for cases with pT1 or pT3a upstaging, and for partial or radical nephrectomy in cases with pT3a upstaging. Clinicopathological parameters were analyzed in univariate and multivariate analyses to evaluate their associations with upstaging. Results: Among the 1,009 eligible patients, 987 patients were included in the analysis. The mean follow-up was 48.5 ± 27.8 months in whole patients. The 2-year recurrence-free survival was worse in the pT3a upstaging group, compared to the pT1 group (87.3% vs. 98.7%; p < 0.001). Partial nephrectomy and radical nephrectomy had no significant difference in 2-year recurrence-free survivals (91.9% vs. 83.7%; p = 0.251). The multivariate analysis revealed that upstaging was associated with old age, cT1b stage, clinical symptoms, and a high Fuhrman grade. Conclusions: Pathological T3a upstaging of cT1 renal cell carcinoma was associated with a poorer prognosis, compared to pT1 disease. However, the surgical technique (radical or partial nephrectomy) did not affect the recurrence rate. Therefore, clinicians should select the treatment method based on the clinical stage, and consider the pathological stage during the follow-up. [ABSTRACT FROM AUTHOR]

Although the overall structure of the chloroplast genome is generally conserved, several sequence variations have been identified that are valuable for plant population and evolutionary studies. Here, we constructed a chloroplast variation map of 30 landrace rice strains of Korean origin, using the Oryza rufipogon chloroplast genome (GenBank: ) as a reference. Differential distribution of single-nucleotide polymorphisms and INDELs across the rice chloroplast genome is suggestive of a region-specific variation. Population structure clustering revealed the existence of two clear subgroups ( indica and japonica) and an admixture group ( aus). Phylogenetic analysis of the 30 landrace rice strains and six rice chloroplast references suggested and supported independent evolution of O. sativa indica and japonica. Interestingly, two aus type accessions, which were thought to be indica type, shared a closer relationship with the japonica type. One hypothesis is that 'Korean aus' was intentionally introduced and may have obtained japonica chloroplasts during cultivation. We also calculated the nucleotide diversity of 30 accessions and compared the results to six rice chloroplast references. These data demonstrated that although nucleotide diversity is low in all strains tested, aus and indica have a higher nucleotide diversity than japonica. [ABSTRACT FROM AUTHOR]

A sugary mutant with low total starch and high sugar contents was compared with its wild type Sindongjin for grain-filling caryopses. In the present study, developing seeds of Sindongjin and sugary mutant from the 11th day after flowering (DAF) were subjected to RNA sequencing (RNA-Seq). A total of 30,385 and 32,243 genes were identified in Sindongjin and sugary mutant. Transcriptomic change analysis showed that 7713 differentially expressed genes (DEGs) (log 2 fold change ≥ 1, false discovery rate (FDR) ≤ 0.001) were identified based on our RNA-Seq data, with 7239 genes up-regulated and 474 down-regulated in the sugary mutant. A large number of DEGs were found related to metabolic, biosynthesis of secondary metabolites, plant-pathogen interaction, plant hormone signal transduction and starch/sugar metabolism. Detailed pathway dissection and quantitative real time PCR (qRT-PCR) demonstrated that most genes involved in sucrose to starch synthesis are up-regulated, whereas the expression of the ADP-glucose pyrophosphorylase small subunit ( OsAGPS2b ) catalyzing the first committed step of starch biosynthesis was specifically inhibited during the grain-filling stage in sugary mutant. Further analysis suggested that the OsAGPS2b is a considerable candidate gene responsible for phenotype of sugary mutant. [ABSTRACT FROM AUTHOR]

Bacterial leaf pustule (BLP) disease is caused by Xanthomonas axonopodis pv. glycines (Xag). To investigate the plant basal defence mechanisms induced in response to Xag, differential gene expression in near-isogenic lines (NILs) of BLP-susceptible and BLP-resistant soybean was analysed by RNA-Seq. Of a total of 46 367 genes that were mapped to soybean genome reference sequences, 1978 and 783 genes were found to be up- and down-regulated, respectively, in the BLP-resistant NIL relative to the BLP-susceptible NIL at 0, 6, and 12h after inoculation (hai). Clustering analysis revealed that these genes could be grouped into 10 clusters with different expression patterns. Functional annotation based on gene ontology (GO) categories was carried out. Among the putative soybean defence response genes identified (GO:0006952), 134 exhibited significant differences in expression between the BLP-resistant and -susceptible NILs. In particular, pathogen-associated molecular pattern (PAMP) and damage-associated molecular pattern (DAMP) receptors and the genes induced by these receptors were highly expressed at 0 hai in the BLP-resistant NIL. Additionally, pathogenesis-related (PR)-1 and -14 were highly expressed at 0 hai, and PR-3, -6, and -12 were highly expressed at 12 hai. There were also significant differences in the expression of the core JA-signalling components MYC2 and JASMONATE ZIM-motif. These results indicate that powerful basal defence mechanisms involved in the recognition of PAMPs or DAMPs and a high level of accumulation of defence-related gene products may contribute to BLP resistance in soybean. [ABSTRACT FROM PUBLISHER]

High-intensity ultraviolet-B (UV-B) irradiation is a complex abiotic stressor resulting in excessive light exposure, heat, and dehydration, thereby affecting crop yields. In the present study, we identified quantitative trait loci (QTLs) for resistance to high-intensity UV-B irradiation in soybean (Glycine max [L.]). We used a genotyping-by-sequencing approach using an F6 recombinant inbred line (RIL) population derived from a cross between Cheongja 3 (UV-B sensitive) and Buseok (UV-B resistant). We evaluated the degree of leaf damage by high-intensity UV-B radiation in the RIL population and identified four QTLs, UVBR12-1, 6-1, 10-1, and 14-1, for UV-B stress resistance, together explaining 20% of the observed phenotypic variation. The genomic regions containing UVBR12-1 and UVBR6-1 and their syntenic blocks included other known biotic and abiotic stress-related QTLs. The QTL with the highest logarithm of odds (LOD) score of 3.76 was UVBR12-1 on Chromosome 12, containing two genes encoding spectrin beta chain, brain (SPTBN, Glyma.12g088600) and bZIP transcription factor21/TGACG motif-binding 9 (bZIP TF21/TGA9, Glyma.12g088700). Their amino acid sequences did not differ between the mapping parents, but both genes were significantly upregulated by UV-B stress in Buseok but not in Cheongja 3. Among five genes in UVBR6-1 on Chromosome 6, Glyma.06g319700 (encoding a leucine-rich repeat family protein) had two nonsynonymous single nucleotide polymorphisms differentiating the parental lines. Our findings offer powerful genetic resources for efficient and precise breeding programs aimed at developing resistant soybean cultivars to multiple stresses. Furthermore, functional validation of the candidate genes will improve our understanding of UV-B stress defense mechanisms. [ABSTRACT FROM AUTHOR]

Salt toxicity is the major factor limiting crop productivity in saline soils. In this paper, 295 accessions including a heuristic core set (137 accessions) and 158 bred varieties were re-sequenced and ~1.65 million SNPs/indels were used to perform a genome-wide association study (GWAS) of salt-tolerance-related phenotypes in rice during the germination stage. A total of 12 associated peaks distributed on seven chromosomes using a compressed mixed linear model were detected. Determined by linkage disequilibrium (LD) blocks analysis, we finally obtained a total of 79 candidate genes. By detecting the highly associated variations located inside the genic region that overlapped with the results of LD block analysis, we characterized 17 genes that may contribute to salt tolerance during the seed germination stage. At the same time, we conducted a haplotype analysis of the genes with functional variations together with phenotypic correlation and orthologous sequence analyses. Among these genes, OsMADS31, which is a MADS-box family transcription factor, had a down-regulated expression under the salt condition and it was predicted to be involved in the salt tolerance at the rice germination stage. Our study revealed some novel candidate genes and their substantial natural variations in the rice genome at the germination stage. The GWAS in rice at the germination stage would provide important resources for molecular breeding and functional analysis of the salt tolerance during rice germination. [ABSTRACT FROM AUTHOR]

Despite Americans' recent heightened awareness of racial inequality, anti-Asian racism at work remains underrecognized and largely unaddressed. In this research, we aim to understand why White bystander coworkers may fail to confront anti-Asian racism. Integrating the moral exclusion perspective and research on racial positions, we propose that due to perceiving Asian Americans as more foreign than other non-White coworkers, White coworkers are less likely to feel anger and engage in confrontation when witnessing anti-Asian racism at work. We first conducted a survey study (Study 1), demonstrating the external validity of the phenomenon that White coworkers are less likely to confront racism when the victim is Asian American versus Black. We then conducted two experiments (Studies 2 and 3) with a realistic, interactive design and behavioral measures of confrontation, supporting our hypothesized mechanisms (i.e., perceived target foreignness and anger). Study 3 further generalized our theory by including Hispanic/Latinx American targets as an additional comparison group and showing that the relative perceived foreignness among Asian American, Hispanic/Latinx American, and Black targets reduced White coworkers' anger and confrontation. We then conclude by discussing the theoretical and practical implications of our work. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

In the current and next-generation Si-based semiconductor manufacturing processes, amorphous carbon layer (ACL) hard masks are garnering considerable attention for high-aspect-ratio (HAR) etching due to their outstanding physical properties. However, a current limitation is the lack of research on the etching characteristics of ACL hard masks under plasma etching conditions. Given the significant impact of hard mask etching on device quality and performance, a deeper understanding of the etching characteristics of ACL is necessary. This study aims to investigate the role of oxygen in the etching characteristics of an ACL hard mask in a complex gas mixture plasma etching process. Our results show that a small change of oxygen concentration (3.5-6.5%) can significantly alter the etch rate and profile of the ACL hard mask. Through our comprehensive plasma diagnostics and wafer-processing results, we have also proven a detailed mechanism for the role of the oxygen gas. This research provides a solution for achieving an outstanding etch profile in ACL hard masks with sub-micron scale and emphasizes the importance of controlling the oxygen concentration to optimize the plasma conditions for the desired etching characteristics., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Background: Proanthocyanidins are oligomeric or polymeric end products of flavonoid metabolic pathways starting with the central phenylpropanoid pathway. Although soybean (Glycine spp.) seeds represent a major source of nutrients for the human diet, as well as components for the cosmetics industry as a result of their high levels of flavonoid metabolites, including isoflavonoids, anthocyanins and proanthocyanidins, the genetic regulatory mechanisms underlying proanthocyanidin biosynthesis in soybean remain unclear., Results: We evaluated interspecific and intraspecific variability in flavonoid components in soybean using 43 cultivars, landraces and wild soybean accessions. We performed transcriptomic profiling of genes encoding enzymes involved in flavonoid biosynthesis using three soybean genotypes, Hwangkeum (elite cultivar), IT109098 (landrace) and IT182932 (wild accession), in seeds. We identified a Glycine max landrace, IT109098, with a proanthocyanidin content as high as that of wild soybean. Different homologous genes for anthocyanidin reductase, which is involved in proanthocyanidin biosynthesis, were detected as differentially expressed genes between IT109098 and IT182932 compared to Hwangkeum., Conclusion: We detected major differences in the transcriptional levels of genes involved in the biosynthesis of proanthocyanidin and anthocyanin among genotypes beginning at the early stage of seed development. The results of the present study provide insights into the underlying genetic variation in proanthocyanidin biosynthesis among soybean genotypes. © 2017 Society of Chemical Industry., (© 2017 Society of Chemical Industry.)

Purpose: We aimed to investigate whether the apparent diffusion coefficient (ADC) value in diffusion-weighted magnetic resonance imaging predicts the prognoses of patients with high-risk prostate cancer., Materials and Methods: A total of 157 patients with high-risk prostate cancer (based on D'Amico's criteria) were included in the analysis. Patients underwent preoperative 3.0 Tesla magnetic resonance imaging within 2 months before radical prostatectomy. Those who received neoadjuvant hormone therapy (33 persons) or radiation therapy (18 persons) were excluded. The ADC of the tumor calculated from 2 b-values (0 and 1,000 s/mm 2 ) was measured. Areas under receiver operating characteristics curves were calculated to maximize the accuracy of the ADC value. Based on the obtained cutoff value, the patients were stratified into 2 groups: Group A consisted of patients with ADC values <746×10 -6 mm 2 /s and group B comprised those with ADC values ≥746×10 -6 mm 2 /s., Results: Group A showed higher rate of lymph positive and biochemical recurrence (BCR) rates than group B. Kaplan-Meier analysis showed that the BCR-free survival rate of group A was much lower than that of group B (p<0.001). On Cox proportional regression analyses, ADC group A (hazard ratio [HR], 3.238, p=0.002) and pathologic lymph node positive (HR, 2.242; p=0.009) were independent predictors of BCR., Conclusions: In patients with high-risk prostate cancer, ADC value is significantly associated with BCR-free survival. Therefore, the ADC value is a useful tool for predicting the prognoses of these high-risk patients., Competing Interests: The author has nothing to disclose.

The depletion of the ozone layer in the stratosphere has led to a dramatic spike in ultraviolet B (UV-B) intensity and increased UV-B light levels. The direct absorption of high-intensity UV-B induces complex abiotic stresses in plants, including excessive light exposure, heat, and dehydration. However, UV-B stress signaling mechanisms in plants including soybean ( Glycine max [L.]) remain poorly understood. Here, we surveyed the overall transcriptional responses of two soybean genotypes, UV-B-sensitive Cheongja 3 and UV-B-resistant Buseok, to continuous UV-B irradiation for 0 (control), 0.5, and 6 h using RNA-seq analysis. Homology analysis using UV-B-related genes from Arabidopsis thaliana revealed differentially expressed genes (DEGs) likely involved in UV-B stress responses. Functional classification of the DEGs showed that the categories of immune response, stress defense signaling, and reactive oxygen species (ROS) metabolism were over-represented. UV-B-resistant Buseok utilized phosphatidic acid-dependent signaling pathways (based on subsequent reactions of phospholipase C and diacylglycerol kinase) rather than phospholipase D in response to UV-B exposure at high fluence rates, and genes involved in its downstream pathways, such as ABA signaling, mitogen-activated protein kinase cascades, and ROS overproduction, were upregulated in this genotype. In addition, the DEGs for TIR-NBS-LRR and heat shock proteins are positively activated. These results suggest that defense mechanisms against UV-B stress at high fluence rates are separate from the photomorphogenic responses utilized by plants to adapt to low-level UV light. Our study provides valuable information for deep understanding of UV-B stress defense mechanisms and for the development of resistant soybean genotypes that survive under high-intensity UV-B stress.

Background: Rice germplasm collections continue to grow in number and size around the world. Since maintaining and screening such massive resources remains challenging, it is important to establish practical methods to manage them. A core collection, by definition, refers to a subset of the entire population that preserves the majority of genetic diversity, enhancing the efficiency of germplasm utilization., Results: Here, we report whole-genome resequencing of the 137 rice mini core collection or Korean rice core set (KRICE&#95;CORE) that represents 25,604 rice germplasms deposited in the Korean genebank of the Rural Development Administration (RDA). We implemented the Illumina HiSeq 2000 and 2500 platform to produce short reads and then assembled those with 9.8 depths using Nipponbare as a reference. Comparisons of the sequences with the reference genome yielded more than 15 million (M) single nucleotide polymorphisms (SNPs) and 1.3 M INDELs. Phylogenetic and population analyses using 2,046,529 high-quality SNPs successfully assigned rice accessions to the relevant rice subgroups, suggesting that these SNPs capture evolutionary signatures that have accumulated in rice subpopulations. Furthermore, genome-wide association studies (GWAS) for four exemplary agronomic traits in the KRIC&#95;CORE manifest the utility of KRICE&#95;CORE; that is, identifying previously defined genes or novel genetic factors that potentially regulate important phenotypes., Conclusion: This study provides strong evidence that the size of KRICE&#95;CORE is small but contains high genetic and functional diversity across the genome. Thus, our resequencing results will be useful for future breeding, as well as functional and evolutionary studies, in the post-genomic era.

Virus-induced gene silencing (VIGS) is an effective tool for the study of soybean gene function. Successful VIGS depends on the interaction between virus spread and plant growth, which can be influenced by environmental conditions. Recently, we developed a new VIGS system derived from the Soybean yellow common mosaic virus (SYCMV). Here, we investigated several environmental and developmental factors to improve the efficiency of a SYCMV-based VIGS system to optimize the functional analysis of the soybean. Following SYCMV: Glycine max-phytoene desaturase (GmPDS) infiltration, we investigated the effect of photoperiod, inoculation time, concentration of Agrobacterium inoculm, and growth temperature on VIGS efficiency. In addition, the relative expression of GmPDS between non-silenced and silenced plants was measured by qRT-PCR. We found that gene silencing efficiency was highest at a photoperiod of 16/8 h (light/dark) at a growth temperature of approximately 27°C following syringe infiltration to unrolled unifoliolate leaves in cotyledon stage with a final SYCMV:GmPDS optimal density (OD)600 of 2.0. Using this optimized protocol, we achieved high efficiency of GmPDS-silencing in various soybean germplasms including cultivated and wild soybeans. We also confirmed that VIGS occurred in the entire plant, including the root, stem, leaves, and flowers, and could transmit GmPDS to other soybean germplasms via mechanical inoculation. This optimized protocol using a SYCMV-based VIGS system in the soybean should provide a fast and effective method to elucidate gene functions and for use in large-scale screening experiments.

Background: R genes are a key component of genetic interactions between plants and biotrophic bacteria and are known to regulate resistance against bacterial invasion. The most common R proteins contain a nucleotide-binding site and a leucine-rich repeat (NBS-LRR) domain. Some NBS-LRR genes in the soybean genome have also been reported to function in disease resistance. In this study, the number of NBS-LRR genes was found to correlate with the number of disease resistance quantitative trait loci (QTL) that flank these genes in each chromosome. NBS-LRR genes co-localized with disease resistance QTL. The study also addressed the functional redundancy of disease resistance on recently duplicated regions that harbor NBS-LRR genes and NBS-LRR gene expression in the bacterial leaf pustule (BLP)-induced soybean transcriptome., Results: A total of 319 genes were determined to be putative NBS-LRR genes in the soybean genome. The number of NBS-LRR genes on each chromosome was highly correlated with the number of disease resistance QTL in the 2-Mb flanking regions of NBS-LRR genes. In addition, the recently duplicated regions contained duplicated NBS-LRR genes and duplicated disease resistance QTL, and possessed either an uneven or even number of NBS-LRR genes on each side. The significant difference in NBS-LRR gene expression between a resistant near-isogenic line (NIL) and a susceptible NIL after inoculation of Xanthomonas axonopodis pv. glycines supports the conjecture that NBS-LRR genes have disease resistance functions in the soybean genome., Conclusions: The number of NBS-LRR genes and disease resistance QTL in the 2-Mb flanking regions of each chromosome was significantly correlated, and several recently duplicated regions that contain NBS-LRR genes harbored disease resistance QTL for both sides. In addition, NBS-LRR gene expression was significantly different between the BLP-resistant NIL and the BLP-susceptible NIL in response to bacterial infection. From these observations, NBS-LRR genes are suggested to contribute to disease resistance in soybean. Moreover, we propose models for how NBS-LRR genes were duplicated, and apply Ks values for each NBS-LRR gene cluster.