Plants adjust their architecture to optimize growth and reproductive success under changing climates. Hypocotyl elongation is a pivotal morphogenic trait that is profoundly influenced by light and ...temperature conditions. While hypocotyl photomorphogenesis has been well characterized at the molecular level, molecular mechanisms underlying hypocotyl thermomorphogenesis remains elusive. Here, we demonstrate that the E3 ubiquitin ligase CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1) conveys warm temperature signals to hypocotyl thermomorphogenesis.
To investigate the roles of COP1 and its target ELONGATED HYPOCOTYL 5 (HY5) during hypocotyl thermomorphogenesis, we employed Arabidopsis mutants that are defective in their genes. Transgenic plants overexpressing the genes were also produced. We examined hypocotyl growth and thermoresponsive turnover rate of HY5 protein at warm temperatures under both light and dark conditions.
Elevated temperatures trigger the nuclear import of COP1, thereby alleviating the suppression of hypocotyl growth by HY5. While the thermal induction of hypocotyl growth is circadian-gated, the degradation of HY5 by COP1 is uncoupled from light responses and timing information.
We propose that thermal activation of COP1 enables coincidence between warm temperature signaling and circadian rhythms, which allows plants to gate hypocotyl thermomorphogenesis at the most profitable time at warm temperatures.
For incompletely reduced graphene oxides (RGOs), an effect of oxygen functional groups such as carboxyl, phenol, carbonyl, and quinone on electrochemical capacitive behavior was studied. To prepare ...RGO thin-film electrodes, a simple fabrication process by (i) dropping and evaporating the graphene oxide (GO) solution, (ii) irradiating pulsed light, and (iii) heat-treating at 200 ∼ 360°C was applied. It was notable that the pulsed light irradiation was effective to prevent the disfiguring of deposited GO thin-film during the thermal reduction. From XRD analyses, interlayer distances of the RGOs were gradually decreased from 0.379 to 0.354nm. As increasing the thermal reduction temperature from 200 to 360°C, XPS O 1s spectra analyses showed that the atomic percentages of carboxyl and phenol of the RGOs were sustained as 5.40±0.36 and 4.77±0.41 at% respectively. Meanwhile, those of carbonyl and quinone of the RGOs were gradually declined from 3.10 to 1.81 and from 1.32 to 0.65 at% with different thermal reduction temperature respectively. For all RGO thin-film electrodes, the specific capacitance from the CV measurement in 6M KOH was sustained as ca. 220 F g−1 at the scan of 5mV s−1. However, in 1M H2SO4, the specific capacitance was gradually decreased from 171 to 136 F g−1. After 100,000 cycles in 6M KOH, 1M H2SO4, and 0.5M Na2SO4, the RGO (200°C) electrodes showed ca. 92, 54, and 104% of the initial capacitances respectively. The atomic percentages of the oxygen functional groups involved in the pseudocapacitive Faradaic reaction were decreased after the cycle test. Especially in 1M H2SO4, quinone group was decreased to ca. 48% of initial atomic percentage, which seems to be a main reason for the drastic reduction of capacitance. The specific pseudocapacitance per unit atomic percentage for either carboxyl or phenol group in 6M KOH was obtained as 12.59 F g−1 at%−1. For carbonyl group in 1M H2SO4, it was a slightly deviated value as 13.55 F g−1 at%−1. For quinone group in 1M H2SO4, it was 27.09 F g−1at%−1.
Many aspects of deep neural networks, such as depth, width, or cardinality, have been studied to strengthen the representational power. In this work, we study the effect of
attention
in convolutional ...neural networks and present our idea in a simple self-contained module, called
Bottleneck Attention Module
(BAM). Given an intermediate feature map, BAM efficiently produces the attention map along two factorized axes,
channel
and
spatial
, with negligible overheads. BAM is placed at
bottlenecks
of various models where the downsampling of feature maps occurs, and is jointly trained in an end-to-end manner. Ablation studies and extensive experiments are conducted in CIFAR-100/ImageNet classification, VOC2007/MS-COCO detection, super resolution and scene parsing with various architectures including mobile-oriented networks. BAM shows consistent improvements over all experiments, demonstrating the wide applicability of BAM. The code and models are available at
https://github.com/Jongchan/attentionmodule
.
The diamond–graphite hybrid thin film with low‐dimensional nanostructure (e.g., nitrogen‐included ultrananocrystalline diamond (N‐UNCD) or the alike), has been employed in many impactful breakthrough ...applications. However, the detailed picture behind the bottom–up evolution of such intriguing carbon nanostructure is far from clarified yet. Here, the authors clarify it, through the concerted efforts of microscopic, physical, and electrochemical analyses for a series of samples synthesized by hot‐filament chemical vapor deposition using methane–hydrogen precursor gas, based on the hydrogen‐dependent surface reconstruction of nanodiamond and on the substrate‐temperature‐dependent variation of the growth species (atomic hydrogen and methyl radical) concentration near substrate. The clarified picture provides insights for a drastic enhancement in the electrochemical activities of the hybrid thin film, concerning the detection of important biomolecule, that is, ascorbic acid, uric acid, and dopamine: their limits of detections are 490, 35, and 25 nm, respectively, which are among the best of the all‐carbon thin film electrodes in the literature. This work also enables a simple and effective way of strongly enhancing AA detection.
The authors clarify the nucleation/growth mechanism of diamond–graphite hybrid thin film with 2D nanostructure (the only successful diamond probe material for neural recording/stimulation), based on nanodiamond surface reconstruction controlled by growth species variation in growth environment. It provides insights for the drastic enhancement of the structure‐optimized thin film performance in simultaneous electrochemical detection of dopamine, ascorbic acid, and uric acid.
Key points
Referring to the muscle memory theory, previously trained muscles acquire strength and volume much faster than naive muscles.
Using extreme experimental models such as synergist ablation ...or steroid administration, previous studies have demonstrated that the number of nuclei increases when a muscle becomes enlarged, which serves as a cellular muscle memory mechanism for the muscle.
In the present study, we found that, when rats were subjected to physiologically relevant resistance training, the number of myonuclei increased and was retained during a long‐term detraining period.
The acquired myonuclei were related to a greater degree of muscle hypertrophic and mitochondrial biogenesis processes following subsequent hypertrophic conditions.
Our data suggest a cellular mechanism supporting the notion that exposing young muscles to resistance training would help to restore age‐related muscle loss coupled with mitochondrial dysfunction in later life.
Muscle hypertrophy induced by resistance training is accompanied by an increase in the number of myonuclei. The acquired myonuclei are viewed as a cellular component of muscle memory by which muscle enlargement is promoted during a re‐training period. In the present study, we investigated the effect of exercise preconditioning on mitochondrial remodelling induced by resistance training. Sprague–Dawley rats were divided into four groups: untrained control, training, pre‐training or re‐training. The training groups were subjected to weight loaded‐ladder climbing exercise training. Myonuclear numbers were significantly greater (up to 20%) in all trained muscles compared to untrained controls. Muscle mass was significantly higher in the re‐training group compared to the training group (∼2‐fold increase). Mitochondrial content, mitochondrial biogenesis gene expression levels and mitochondrial DNA copy numbers were significantly higher in re‐trained muscles compared to the others. Oxidative myofibres (type I) were significantly increased only in the re‐trained muscles. Furthermore, in vitro studies using insulin‐like growth factor‐1‐treated L6 rat myotubes demonstrated that myotubes with a higher myonuclear number confer greater expression levels of both mitochondrial and nuclear genes encoding for constitutive and regulatory mitochondrial proteins, which also showed a greater mitochondrial respiratory function. These data suggest that myonuclei acquired from previous training facilitate mitochondrial biogenesis in response to subsequent retraining by (at least in part) enhancing cross‐talk between mitochondria and myonuclei in the pre‐conditioned myofibres.
Key points
Referring to the muscle memory theory, previously trained muscles acquire strength and volume much faster than naive muscles.
Using extreme experimental models such as synergist ablation or steroid administration, previous studies have demonstrated that the number of nuclei increases when a muscle becomes enlarged, which serves as a cellular muscle memory mechanism for the muscle.
In the present study, we found that, when rats were subjected to physiologically relevant resistance training, the number of myonuclei increased and was retained during a long‐term detraining period.
The acquired myonuclei were related to a greater degree of muscle hypertrophic and mitochondrial biogenesis processes following subsequent hypertrophic conditions.
Our data suggest a cellular mechanism supporting the notion that exposing young muscles to resistance training would help to restore age‐related muscle loss coupled with mitochondrial dysfunction in later life.
To clarify transmissibility of the severe acute respiratory syndrome coronavirus 2 Omicron variant, we determined serial intervals and secondary attack rates among household contacts in South Korea. ...Mean serial interval for 12 transmission pairs was 2.9 days, and secondary attack rate among 25 households was 50.0%, raising concern about a rapid surge in cases.
The circadian clock may help to control the development patterns which allow the florets on a sunflower head to go through their final stages of maturation at precisely the right time.
ABSTRACT
Coordinated morphogenic adaptation of growing plants is critical for their survival and propagation under fluctuating environments. Plant morphogenic responses to light and warm ...temperatures, termed photomorphogenesis and thermomorphogenesis, respectively, have been extensively studied in recent decades. During photomorphogenesis, plants actively reshape their growth and developmental patterns to cope with changes in light regimes. Accordingly, photomorphogenesis is closely associated with diverse growth hormonal cues. Notably, accumulating evidence indicates that light‐directed morphogenesis is profoundly affected by two recently identified phytochemicals, karrikins (KARs) and strigolactones (SLs). KARs and SLs are structurally related butenolides acting as signaling molecules during a variety of developmental steps, including seed germination. Their receptors and signaling mediators have been identified, and associated working mechanisms have been explored using gene‐deficient mutants in various plant species. Of particular interest is that the KAR and SL signaling pathways play important roles in environmental responses, among which their linkages with photomorphogenesis are most comprehensively studied during seedling establishment. In this review, we focus on how the phytochemical and light signals converge on the optimization of morphogenic fitness. We also discuss molecular mechanisms underlying the signaling crosstalks with an aim of developing potential ways to improve crop productivity under climate changes.
Light‐directed plant morphogenesis is profoundly affected by two recently identified phytochemicals, karrikins and strigolactones. The phytochemical and light signals coordinately converge on the optimization of morphogenic fitness during seedling establishment.
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