301 research outputs found
Stimulation of trans-resveratrol biosynthesis in Vitis vinifera cv. Kyoho cell suspension cultures by 2, 3-dihydroxypropyl jasmonate elicitation
Background: Plant cell suspension culture of Vitis vinifera is a
promising technology for investigating different factors that are able
to induce and/or modify stilbenes biosynthesis. Jasmonates have been
reported to play an important role in a signal transduction pathway
that regulates defence responses as well as the production of secondary
metabolites. In this study, 2, 3-dihydroxypropyl jasmonate (DHPJA) was
used to investigate its effect on stimulating trans-resveratrol (t-R)
accumulation and the plant defence responses in Vitis vinifera cv.
Kyoho cell suspension cultures for the first time. Results: It
demonstrated that DHPJA had superior effects on stilbenoids
accumulation over methyl jasmonate (MeJA). The optimal condition was
150 \u3bcM DHPJA added on day 15 of cultivation period, with the
highest level of t-R accumulation which was increased 1.8-fold and
1.3-fold compared with the control and 150 \u3bcM MeJA respectively.
DHPJA induced stronger plant defence responses, including oxidative
burst and activation of L-phenylalanine ammonia lyase (PAL) than MeJA.
H2O2 generation induced by DHPJA played a significant role in enhancing
t-R accumulation. Adding a specific inhibitor of H2O2 signalling
pathway inhibited DHPJA-induced t-R accumulation, but had no effects on
DHPJA-induced other metabolites accumulation, which resulted in
regulations of product diversity. Conclusions: This study demonstrated
that DHPJA was an efficient elicitor to enhance t-R accumulation by
activating stronger oxidative burst, and H2O2 signalling pathway could
regulate product diversity in DHPJA-induced V. vinifera cv. Kyoho cell
suspension cultures
Application of evolution-based uncertainty design on gear
The evolution of mechanical parameters, a factor affecting the mechanical reliability, has gathered more attention nowadays. However, studies on time varying uncertainty can hardly be found. A new method based on evolution-based uncertainty design (EBUD) is applied to the design of gear in this paper. Considering the wear evolution over the lifetime, a tooth wearâs time-varying uncertainty model based on the continuous-time model and Ito lemma is established. Drift and volatility functions dependent on the drift rate and volatility rate of rotational speed and torque are used to express the time-varying uncertainty of tooth thickness. The method can predict the reliability and provide an instruction in reliability improving, maintenance and repair of the gear system
Elevated Plasma microRNA-105-5p Level in Patients With Idiopathic Parkinsonâs Disease: A Potential Disease Biomarker
Parkinsonâs disease (PD) is the second most common neurodegenerative disease, which still lacks a biomarker to aid in diagnosis and to differentiate diagnosis at the early stage of the disease. microRNAs (miRNAs) are small and evolutionary conserved non-coding RNAs that are involved in post-transcriptional gene regulation. Several miRNAs have been proposed as potential biomarkers in several diseases. In the present study, we screened miRNAs using a network vulnerability analysis, to evaluate their potential as PD biomarkers. We first extracted miRNAs that were differentially expressed between PD and healthy controls (HC) samples. Then we constructed the PD-specific miRNA-mRNA network and screened miRNA biomarkers using a new bioinformatics model. With this model, we identified miR-105-5p as a putative biomarker for PD. Moreover, we measured miR-105-5p levels in the plasma of patients with idiopathic PD (IPD) (n = 319), neurological disease controls (NDC, n = 305) and HC (n = 273) using reverse transcription real-time quantitative PCR (RT-qPCR). Our data clearly demonstrated that the plasma miR-105-5p level in IPD patients was significantly higher than those of HC (251%, p < 0.001) and NDC (347%, p < 0.001). There was no significant difference in miR-105-5p expression between IPD patients with or without anti-PD medications. Interestingly, we found that the plasma miR-105-5p expression level may be able to differentiate IPD from parkinsonian syndrome, essential tremor and other neurodegenerative diseases. We believe that a change in the plasma miR-105-5p level is a potential biomarker for IPD
Omni-Line-of-Sight Imaging for Holistic Shape Reconstruction
We introduce Omni-LOS, a neural computational imaging method for conducting
holistic shape reconstruction (HSR) of complex objects utilizing a
Single-Photon Avalanche Diode (SPAD)-based time-of-flight sensor. As
illustrated in Fig. 1, our method enables new capabilities to reconstruct
near- surrounding geometry of an object from a single scan spot. In
such a scenario, traditional line-of-sight (LOS) imaging methods only see the
front part of the object and typically fail to recover the occluded back
regions. Inspired by recent advances of non-line-of-sight (NLOS) imaging
techniques which have demonstrated great power to reconstruct occluded objects,
Omni-LOS marries LOS and NLOS together, leveraging their complementary
advantages to jointly recover the holistic shape of the object from a single
scan position. The core of our method is to put the object nearby diffuse walls
and augment the LOS scan in the front view with the NLOS scans from the
surrounding walls, which serve as virtual ``mirrors'' to trap lights toward the
object. Instead of separately recovering the LOS and NLOS signals, we adopt an
implicit neural network to represent the object, analogous to NeRF and NeTF.
While transients are measured along straight rays in LOS but over the spherical
wavefronts in NLOS, we derive differentiable ray propagation models to
simultaneously model both types of transient measurements so that the NLOS
reconstruction also takes into account the direct LOS measurements and vice
versa. We further develop a proof-of-concept Omni-LOS hardware prototype for
real-world validation. Comprehensive experiments on various wall settings
demonstrate that Omni-LOS successfully resolves shape ambiguities caused by
occlusions, achieves high-fidelity 3D scan quality, and manages to recover
objects of various scales and complexity
Promoting social and emotional learning for students through sports-based youth development programs using models-based practice
Decades of research and practices on Social and Emotional Learning (SEL) have formed a foundational body of knowledge that the development of SEL skills is positively associated with studentsâ academic achievement and later life success (Durlak et al., 2011; Elias et al., 1997; Weissberg et al., 2015). This proposed research argues that learning is a social and emotional enterprise. Therefore, educational efforts should ensure an emphasis on developing studentsâ SEL skills (Elias, 2019). SEL programs and practices were initially developed in schools (Elias et al., 1997). However, the lack of clear leadership and support for teachers in schools around the social and emotional aspects of learning (Elias, 2019), school closures, and the stringent management practices during the COVID-19 pandemic have made schools a challenging place for studying and developing studentsâ SEL competencies (Viner et al., 2020). The situation is highly likely worse for underserved students, including low-income, underrepresented racial/ethnic minorities, and first-generation students. Underserved students are more vulnerable to the lack of environmental education opportunities to develop SEL skills due to the issues of poverty, racism, oppression, and segregation (Holt et al., 2011; Martinek & Hellison, 1997, Coll et al., 1996), which may lead to a series of social issues and juvenile crimes (Jewett & Kuhn, 2016). One alternative way to provide educational opportunities on SEL for underserved students is participating in Sport-based Youth Development (SBYD) programs (Holt, 2016; Hemphill et al., 2019). This is especially true when some SBYD programs are still operating and available during the COVID-19 pandemic. In SBYD programs, students can be taught to âthink through core program values beyond sportâ and learn âhow to navigate through potential environmental barriersâ in their lives (Jacobs & Wright, 2019, p. 13). SBYD programs have been proposed as potential contexts for promoting certain competencies that align well with the SEL framework for underserved students (Gould & Carson, 2008; Papacharisis et al., 2005). In comparison to other organized activities, students in SBYD programs reported significantly more positive experiences related to the initiative, emotional regulation, and teamwork (Larson et al., 2006). For decades, researchers have been studying pedagogical practices that promote SEL skills in school physical education and sports settings. Most popular pedagogical practices focusing on studentsâ development of SEL skills include Teaching Personal and Social Responsibility (Hellison, 2011), Cooperative Learning (Dyson et al., 2020), Sports Education (Siedentop et al., 2004), and Adventure-based Learning (Sutherland & Stuhr, 2014). Those pedagogical practices are called models-based practices (MBP). While the benefits of SBYD in promoting SEL are evident, there is a limited empirical examination on how MBP could be utilized to promote studentsâ SEL skills in SBYD programs (Talebzadeh & Jarfari, 2012). The purpose of this dissertation study is to promote studentsâ SEL skills in SBYD programs using MBP. The dissertation study was guided by three research questions: (a) How do students experience SEL in an SBYD program grounded in TPSR? (b) What are the SEL skills students develop in an SBYD program grounded in a hybrid pedagogy of TPSR and CL? and (c) What is the impact of the SBYD program grounded in the hybridization of TPSR and CL on studentsâ physical, social, and emotional development? The dissertation study was conducted in two soccer-based SBYD programs. Guided by a participatory action research approach (Chatterton et al., 2007), the researcher investigated the Saturday Soccer program grounded in TPSR. Another SBYD program, Beyond Soccer Field, was initiated and led by the researcher using a hybrid pedagogy grounded in TPSR and CL. A total of 40 underserved students aged 8 to 14 years old participated in those two programs. This dissertation study adopted a case study design (Stake, 2006). Drawing on the qualitative and quantitative research traditions, the researcher collected data using semi-structured interviews, field notes, self-reflective journals, ACTi Graph GT9X 3-axis accelerometers (ActiGraph, LLC, Pensacola, FL), the Loughborough soccer passing test (Ali, et al., 2007), and the Personal and Social Responsibility Questionnaire (Waston, et al., 2003). Deductive and inductive analysis, constant comparison (Miles et al., 2014), repeated-measures multivariate analysis of variance (Johnson & Wichern, 2007), and paired t-test were utilized for data analysis. Findings in Chapter Four (research question one) confirmed that TPSR could be an effective pedagogical practice that promotes studentsâ development of SEL skills in SBYD programs. Findings in Chapter Five (research question two) provided qualitative evidence, indicating the hybridization of CL and TPSR could better facilitate the program practices and promote studentsâ development of SEL skills, including respect, effort, teamwork, and leadership. Findings in Chapter Six (research question three) provided quantitative and qualitative evidence, showing that the SBYD program grounded in the hybridization of TPSR and CL could significantly promote studentsâ physical, social, and emotional development. Collectively, those findings suggest TPSR and CL can be hybridized as an effective pedagogical practice that promotes studentsâ physical, social, and emotional development in SBYD programs
Transcriptome analysis of two pepper genotypes infected with pepper mild mottle virus
Pepper mild mottle virus (PMMoV) poses a significant threat to pepper production because it is highly contagious and extremely persistent in soil. Despite this threat, little is known about the molecular processes that underlie plant responses to pepper mild mottle virus. Here, we performed RNA sequencing of tolerant (â17-p63â) and susceptible (â16-217â) pepper genotypes after pepper mild mottle virus or mock inoculation. Viral accumulation in systemic leaves was lower in the pepper mild mottle virus-resistant 17-p63 genotype than in the pepper mild mottle virus-sensitive 16-217 genotype, and infection symptoms were more apparent in systemic leaves of 16-217 than in those of 17-p63 at the same timepoints during the infection process. We identified 2,959 and 2,159 differentially expressed genes (DEGs) in systemic leaves of infected 16-217 and 17-p63, respectively. Through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis of differentially expressed genes from both genotypes revealed significant enrichment of the MAPK signaling pathway, plantâpathogen interaction, and flavonoid biosynthesis. A number of differentially expressed genes showed opposite trends in relation to stress resistance and disease defense in the two genotypes. We also performed weighted gene co-expression network analysis (WGCNA) of all samples and identified modules associated with resistance to pepper mild mottle virus, as well as seven hub genes. These results identify candidate virus resistance genes and provide insight into pepper defense mechanisms against pepper mild mottle virus
Calf muscle pump tensing as a novel maneuver to improve the diagnostic performance of detecting patent foramen ovale during transesophageal echocardiography
ObjectiveThe Valsalva maneuver is the most sensitive provocative maneuver for patent foramen ovale detection. However, nearly half of patients are unable to perform the Valsalva maneuver well. The aim of this study was to investigate the mechanism of action of calf muscle pump tensing (TENSE) as a novel patent foramen ovale (PFO) provocative maneuver and to evaluate the diagnostic value for PFO and the effect on right-to-left shunt volume compared with the Valsalva maneuver.MethodsThis study prospectively investigated 171 patients who were highly suspected to have PFO clinically. Five patients with atrial septal defects newly diagnosed on transesophageal echocardiography (TEE) were excluded. 166 patients were injected with agitated saline under three provocative maneuvers: Valsalva maneuver, TENSE, and Valsalva + TENSE combined maneuver. The patients were divided into the effective Valsalva group (n = 93) and ineffective Valsalva group (n = 73) according to whether they could perform an effective Valsalva maneuver. TENSE consisted of the straightening of both lower limbs, and when the right atrium was filled with microbubbles, the patient performed instantaneous ankle dorsiflexion movements while maintaining dorsiflexion for 3â5 s.ResultsOverall, the PFO detection rate of the Valsalva + TENSE combined maneuver (78 [50.1%]) was significantly higher than that of the Valsalva maneuver (51 [30.7%]) and TENSE maneuver (57 [34.3%]) (P < 0.001). In the patients who were able to perform an effective Valsalva maneuver, the PFO detection rate by TENSE was not significantly different from that by the Valsalva maneuver (Valsalva 37/93 [39.8%] vs. TENSE 31/93 [33.3%], P > 0.05), while for the patients who performed an ineffective Valsalva maneuver, the PFO detection rate by the TENSE maneuver was higher than that by the Valsalva maneuver (TENSE 26/73 [35.6%] vs. Valsalva14/73[19.2%], P = 0.017).ConclusionTENSE is a simple and effective provocative maneuver in the diagnosis of PFO using TEE and can assist the Valsalva maneuver. For patients who cannot perform an effective Valsalva maneuver, TENSE can be an alternative to the Valsalva maneuver to some extent
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