Abstract
Spin-valley locking in monolayer transition metal dichalcogenides has attracted enormous interest, since it offers potential for valleytronic and optoelectronic applications. Such an exotic ...electronic state has sparsely been seen in bulk materials. Here, we report spin-valley locking in a Dirac semimetal BaMnSb
2
. This is revealed by comprehensive studies using first principles calculations, tight-binding and effective model analyses, angle-resolved photoemission spectroscopy measurements. Moreover, this material also exhibits a stacked quantum Hall effect (QHE). The spin-valley degeneracy extracted from the QHE is close to 2. This result, together with the Landau level spin splitting, further confirms the spin-valley locking picture. In the extreme quantum limit, we also observed a plateau in the
z
-axis resistance, suggestive of a two-dimensional chiral surface state present in the quantum Hall state. These findings establish BaMnSb
2
as a rare platform for exploring coupled spin and valley physics in bulk single crystals and accessing 3D interacting topological states.
The role of many genes and interactions among genes involved in flowering time have been studied extensively in Arabidopsis, and the purpose of this study was to investigate how effectively results ...obtained with the model species Arabidopsis can be applied to the Brassicacea with often larger and more complex genomes. Brassica rapa represents a very close relative, with its triplicated genome, with subgenomes having evolved by genome fractionation. The question of whether this genome fractionation is a random process, or whether specific genes are preferentially retained, such as flowering time (Ft) genes that play a role in the extreme morphological variation within the B. rapa species (displayed by the diverse morphotypes), is addressed. Data are presented showing that indeed Ft genes are preferentially retained, so the next intriguing question is whether these different orthologues of Arabidopsis Ft genes play similar roles compared with Arabidopsis, and what is the role of these different orthologues in B. rapa. Using a genetical–genomics approach, co-location of flowering quantitative trait loci (QTLs) and expression QTLs (eQTLs) resulted in identification of candidate genes for flowering QTLs and visualization of co-expression networks of Ft genes and flowering time. A major flowering QTL on A02 at the BrFLC2 locus co-localized with cis eQTLs for BrFLC2, BrSSR1, and BrTCP11, and trans eQTLs for the photoperiod gene BrCO and two paralogues of the floral integrator genes BrSOC1 and BrFT. It is concluded that the BrFLC2 Ft gene is a major regulator of flowering time in the studied doubled haploid population.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Considering initial axial loads, dynamics and stability of an inner functionally graded cylindrical shell conveying swirling fluid (i.e., water) in the annulus between the flexible inner shell and ...the identical rigid outer shell are investigated by the traveling wave approach. Shell motions are described by Donnell’s thin shell equations. The fluid forces associated with shell motions are treated in the frame of the potential flow theory. The theoretical analysis is conducted by the zero-level contour method. The critical velocities of losing stability are determined. The influences of angular flow on the critical axial velocity and axial flow on the critical annular velocity are studied. Moreover, effects of the magnitude and the direction of initial axial loads on the critical velocities are fully discussed.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Considering thermal loads, a dynamic stability analysis is presented for a flexible cylindrical shell conveying a viscous, incompressible, swirling fluid in the annulus between the inner shell and ...the outer shell in this paper. The inviscid fluid-dynamic forces associated with shell motions are treated in the frame of the potential flow theory. And the steady viscous forces are derived by using fully developed turbulent theory. The thermal loads are determined by the thermo-elastic theory. Shell motions are described by Flügge's thin shell equations, which are modified to incorporate the prestresses relating to the steady viscous forces. The theoretical analysis is conducted by the zero-level contour method and the Galerkin's method. This study shows that, for annular flow, the effect of viscosity renders the system more unstable. Fluid rotation strongly degrades the stability of the shell. The influences of a combined action of the viscous annular flow having two velocity components and the thermal loads on the stability of shells are discussed in detail. Also, the critical temperature rise is found.
•The viscous effect of fluid destabilizes the annular flow-shell system.•The rotation of fluid lowers the critical axial flow speed.•A combined action of the fluid forces and thermal loads degrades the stability of shells.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Aims
The aim of this study was to characterize a fungal endophyte Y3 from pigeon pea (Cajanus cajan L. Millsp), as a novel producer of vitexin, and its culture medium optimization and antioxidant ...activity.
Methods and Results
The endophyte from the leaves of pigeon pea was identified as Dichotomopilus funicola by the morphological and molecular characteristics. The most important medium variables affecting vitexin production in liquid culture of D. funicola Y3 were screened by Plackett–Burman design, and three culture medium constituents (i.e. l‐phenylalanine, salicylic acid and CuSO4·5H2O) were identified to play significant roles in vitexin production. The most significant factors were further optimized using by central composite design with response surface methodology. The DPPH radical‐scavenging assay indicated that fungal vitexin exhibited notable antioxidant activity with an EC50 value of 164 μg l−1.
Conclusions
First, a novel endophyte vitexin‐producing Dichotomopilus funicola Y3 was isolated from pigeon pea (Cajanus cajanL. Millsp.). The maximum vitexin yield was obtained as 78·86 mg l−1 under the optimum culture medium constituents: 0·06 g l−1 l‐phenylalanine, 0·21 g l−1 salicylic acid, and 0·19 g l−1 CuSO4·5H2O in medium, which is 4·59‐fold higher than that in the unoptimized medium. Also, fungal vitexin clearly demonstrated its antioxidant potential.
Significance and Impact of the Study
These findings provide an alternative source for large‐scale production of vitexin by endophytic fungal fermentation and have a promising prospect in food and pharmaceutical industry.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Abstract Background The aim of the current study is to evaluate the prevalence, severity and possible risk factors of systemic reactions (SRs) to subcutaneous allergen immunotherapy (SCIT) in ...children and adolescents with asthma in Hangzhou, east China's Zhejiang province. Methods From January 2011 to December 2016, this survey analysed the SCIT-related SRs involving 429 patients (265 children and 134 adolescents) affected by allergic asthma. Recorded data included demographics, diagnosis, patient statuses, pulmonary function testing results before and after each injection, allergen dosage, and details of SRs. Results All patients finished the initial phase and six patients withdrew during the maintenance phase. There were 2.59% (328/12,655) SRs in all injections (3.28% in children and 1.47% in adolescents); 15.62% (67/429) patients experienced SRs (18.49% children and 10.98% adolescents). There were 54.57% SRs of grade 1; 42.37% SRs of grade 2; 3.05% SRs of grade 3; and no grades 4 or grade 5 SRs occurred in patients. Most reactions were mild, and were readily controlled by immediate emergency treatment. There was no need for hospitalisation. The occurrence of SRs was significantly higher in children than that in adolescents ( p < 0.01). A higher ratio of SRs was found among patients with moderate asthma. Conclusion This retrospective survey showed that properly-conducted SCIT was a safe treatment for children and adolescents with asthma in Hangzhou, East China. Children and patients with moderate asthma may be prone to develop SRs.
Volunteer geographic information (VGI) and citizen science (CS) have been used as a way to promote a form of democratization of knowledge. Crowdsourcing facilitates the massive collection of data ...through nonexpert volunteers. This study compares 57 VGI and CS projects through a cross-case comparison method to explore the level of involvement of participants, based on three main analytic dimensions (project rationale, actor interaction, and data flow) and 12 sub-variables. The primary goal of this research is to analyze the purpose and the role of technology in VGI and CS projects, using three matrices to explore emerging trade-offs. Finally, we synthesized the workflow of VGI and CS project and compared based on project purposes. At the end of this study, five main purposes were found among the selected projects, uncovering that data collection is the most common purpose. A general workflow can be conceptualized, but detail implementation will involve various trade-offs, especially between local involvement and large-area expert-oriented protocol implementations. By exploring diverse relationships among selected variables of analysis in VGI and CS projects, this study pretends to build a foundation for larger, global meta-analysis that can bring some transparency in the epistemic interactions between experts and nonexperts.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
Summary
Background
Damage to melanocytes induced by oxidative stress plays an important role in the pathogenesis of vitiligo. A polyphenol found in green tea, (‐)‐epigallocatechin‐3‐gallate (EGCG), ...exhibits certain antioxidative effects in the treatment of various diseases. The major problem that limits the clinical application of this polyphenol is its low bioavailability and stability. Peracetylated EGCG (AcEGCG), a fully acetylated derivative of EGCG, is more stable and bioavailable than EGCG, but the effects of its action on human epidermal melanocytes have not been elucidated.
Aim
To compare the protective effects of AcEGCG and EGCG on hydrogen peroxide (H2O2)‐induced damage to human melanocytes.
Methods
Effects of AcEGCG and EGCG on human melanocytes were examined by measuring cell viability, levels of reactive oxygen species (ROS), the mitochondrial membrane potential (ΔΨm)and protein levels of caspase‐9, caspase‐3 and p38 mitogen‐activated protein kinase.
Results
Both AcEGCG and EGCG decreased ROS generation, restored lost mitochondrial membrane potential and reduced H2O2‐induced apoptosis in melanocytes. All of these effects were more pronounced with AcEGCG than with EGCG. Furthermore, AcEGCG effectively suppressed H2O2‐induced p38 mitogen‐activated protein kinase phosphorylation, which has been suggested to contribute to melanocyte damage.
Conclusions
AcEGCG is a more potent agent than EGCG for protection of melanocytes from oxidative damage.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
The purpose of this study was to develop quantitative parameters using range of motion (ROM) of shanks, thighs and knees to evaluate the effect of deep brain stimulation (DBS) on gait performance and ...freezing of gait (FOG) of patients with advanced Parkinson’s disease (PD). Three patients with FOG due to advanced Parkinson’s disease who has received DBS were recruited. The recruited subjects were instructed to walk on a 100-meter path in three conditions: 60 Hz DBS (60 Hz), 130 Hz DBS (130 Hz) and no DBS (Off). Five inertial measurement unit sensors were attached to subjects’ sacrum, bilateral shanks and thighs respectively. Quantified parameters included (1) spatial parameters: shanks, thighs and knees ROM; (2) temporal parameters: stride time, stance time duration and double support time percentage; (3) FOG severity: the percentage of FOG duration during path walking. Three subjects’ ROM of right shank significantly increased in 60 Hz,130 Hz and Off order. Compared to 130 Hz, right shank ROM of subjects S1, S2 and S3 significantly increased 13.2%, 99.6% and 6.1% in 60 Hz, respectively. In temporal parameters results, only double support time percentage was significantly different between 60 Hz and 130 Hz in all three subjects. When compared to 130 Hz, the double support time percentage of S1 and S2 significantly decreased 6.3% and 18.4% in 60 Hz, and that of S3 significantly increased 4.4%. ROM of right shank and FOG severity were highly correlated (R2 = 0.71). Shank ROM could represent subjects’ gait performance under different stimulation conditions. Shank ROM could be treated as a reference for clinicians to evaluate gait performance and severity of FOG immediately when DBS frequency is adjusted. This study demonstrated the potential of using objective parameters to optimize the DBS through assessing the gait performance changes in the clinic.
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