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Solution-based growth of magnetic FePt-FeCo (core-shell) nanoparticles with a controllable shell thickness has been demonstrated. The transition from spin canting to exchange coupling of FePt-FeCo core-shell nanostructures leads to a 28% increase in the coercivity (12.8 KOe) and a two-fold enhancement in the energy product (9.11 MGOe).

Sucrose transporters (SUTs) play vital roles in phloem sucrose unloading and transportation in wheat grains. However, the genomic information regarding the SUT gene family and their expression patterns in response to heat stress in grains of male-sterile wheat (Triticum aestivum L.) lines has not been systematically studied. In this study, a thorough examination of the wheat SUT gene family was conducted, focusing on their expression patterns in male-sterile lines under heat stress conditions in grain tissues. A total of 19 SUT genes were identified, with phylogenetic analysis indicating their classification into five distinct groups. Polyploidization was identified as a substantial factor in the expansion of SUT genes, with segmental duplication being the predominant mechanism driving the evolutionary expansion of the SUT gene family in wheat. Transcriptome data indicate that the expression levels of TaSUT1 and TaSUT2 were higher than other SUT genes in grains of male-sterile lines. The TaSUT1 expression showed a gradual decreasing trend, while TaSUT2 showed a reverse trend with the process of grain filling. After heat stress, the TaSUT1 expression in grains of male-sterile lines was first significantly increased and then significantly decreased with the filling stage extension, aligning with the observed trend of sucrose levels, indicating that heat stress may decrease the grain weight by reducing sucrose unloading and transportation process in grains. These results provide a systematic analysis of the SUT gene family and lay a theoretical foundation for us to study the grain filling of male-sterile lines in response to abiotic stress. [ABSTRACT FROM AUTHOR]

Summary: Drought is a deleterious abiotic stress factor that constrains crop growth and development. Post‐translational modification of proteins mediated by the ubiquitin–proteasome system is an effective strategy for directing plant responses to stress, but the regulatory mechanisms in wheat remain unclear. In this study, we showed that TaSDIR1‐4A is a positive modulator of the drought response. Overexpression of TaSDIR1‐4A increased the hypersensitivity of stomata, root length and endogenous abscisic acid (ABA) content under drought conditions. TaSDIR1‐4A encodes a C3H2C3‐type RING finger protein with E3 ligase activity. Amino acid mutation in its conserved domain led to loss of activity and altered the subcellular localization. The membrane‐bound transcription factor TaWRKY29 was identified by yeast two‐hybrid screening, and it was confirmed as interacting with TaSDIR1‐4A both in vivo and in vitro. TaSDIR1‐4A mediated the polyubiquitination and proteolysis of the C‐terminal amino acid of TaWRKY29, and its translocation from the plasma membrane to the nucleus. Activated TaWRKY29 bound to the TaABI5 promoter to stimulate its expression, thereby positively regulating the ABA signalling pathway and drought response. Our findings demonstrate the positive role of TaSDIR1‐4A in drought tolerance and provide new insights into the involvement of UPS in the wheat stress response. [ABSTRACT FROM AUTHOR]

Simple Summary: We have demonstrated that a fractionated PDT scheme, delivered using a two-hour interval between two light delivery treatments, significantly improves long-term efficacy of Photofrin-mediated PDT while reducing side effects. Reactive Oxygen Species Explicit Dosimetry (ROSED), utilizing direct measurements of in vivo light fluence, in vivo Photofrin concentration, and in vivo tissue oxygenation concentration, were used to determine the concentration of reacted reactive oxygen species, [ROS]rx, as a dosimetry quantity for PDT treatment. We found that a threshold Photofrin dose of 0.78 mM is required for the complete cure (90-day survival) of RIF tumors using fractionated Photofrin-mediated PDT treatment. To our knowledge, this is the first report of this parameter. This study investigates the effect of fractionated (two-part) PDT on the long-term local control rate (LCR) using the concentration of reactive oxygen species ([ROS]rx) as a dosimetry quantity. Groups with different fractionation schemes are examined, including a 2 h interval between light delivery sessions to cumulative fluences of 135, 180, and 225 J/cm2. While the total treatment time remains constant within each group, the division of treatment time between the first and second fractionations are explored to assess the impact on long-term survival at 90 days. In all preclinical studies, Photofrin is intravenously administered to mice at a concentration of 5 mg/kg, with an incubation period between 18 and 24 h before the first light delivery session. Fluence rate is fixed at 75 mW/cm2. Treatment ensues via a collimated laser beam, 1 cm in diameter, emitting light at 630 nm. Dosimetric quantities are assessed for all groups along with long-term (90 days) treatment outcomes. This study demonstrated a significant improvement in long-term survival after fractionated treatment schemes compared to single-fraction treatment, with the optimal 90-day survival increasing to 63%, 86%, and 100% vs. 20%, 25%, and 50%, respectively, for the three cumulative fluences. The threshold [ROS]rx for the optimal scheme of fractionated Photofrin-mediated PDT, set at 0.78 mM, is significantly lower than that for the single-fraction PDT, at 1.08 mM. [ABSTRACT FROM AUTHOR]

Summary: Pathogenic fungi use secreted effector proteins to suppress immunity and support their infection, but effectors have also been reported from fungi that engage in nutritional symbioses with plants. Sequence‐based effector comparisons between pathogens and symbiotic arbuscular mycorrhizal (AM) fungi are hampered by the huge diversity of effector sequences even within closely related microbes.To find sequence‐divergent but structurally similar effectors shared between symbiotic and pathogenic fungi, we compared secreted protein structure models of the AM fungus Rhizophagus irregularis to known pathogen effectors. We identified proteins with structural similarity to known Fusarium oxysporum f. sp. lycopersici dual domain (FOLD) effectors, which occur in low numbers in several fungal pathogens. Contrastingly, FOLD genes from AM fungi (MycFOLDs) are found in enlarged and diversified gene families with higher levels of positive selection in their C‐terminal domains.Our structure model comparison suggests that MycFOLDs are similar to carbohydrate‐binding motifs. Different MycFOLD genes are expressed during colonisation of different hosts and MycFOLD‐17 transcripts accumulate in plant intracellular arbuscules.The exclusive presence of MycFOLDs across unrelated plant‐colonising fungi, their inducible expression, lineage‐specific sequence diversification and transcripts in arbuscules suggest that FOLD proteins act as effectors during plant colonisation of symbiotic and pathogenic fungi. [ABSTRACT FROM AUTHOR]

Hybrid wheat is considered to be one of the main ways to greatly improve the wheat yield in the future, and population construction is an important factor affecting their yield heterosis formation. In order to clarify the effect of population regulation of hybrid wheat on source–sink systems, the two-line hybrid wheat variety Jingmai 6 was used to carry out relevant research in this experiment. The leaf area index (LAI) of Jingmai 6 showed an increasing trend, while the tiller-spike rate exhibited a downward trend with the increase of planting density. The total accumulation of dry matter at maturity increased with the increase of planting density, among which the relative proportion of dry matter pre-anthesis gradually increased, while that after anthesis gradually decreased. The sink capacity and spikes number of hybrid wheat were positively correlated with the grain yield. There was higher sink capacity, spike to leaf ratio and grain to leaf ratio under A2 and A3 conditions. With the increase of planting density, the hybrid wheat yield showed a unimodal curve, and A3 had the highest grain yield. Combined with the change trend of dry matter accumulation before and after anthesis, it was proved that suitable planting density was the key to obtaining high yield of hybrid wheat. [ABSTRACT FROM AUTHOR]

Smooth and uniform epitaxial ultrathin MgB2 films are desired for various electronic applications including hot-electron bolometers and single-photon detectors. However, the growth of ultrathin MgB2 films on SiC substrates using the Hybrid Physical-Chemical Vapor Deposition was dominated by the Volmer-Weber or island growth mode, which limited the minimum thickness for a conductive MgB2 film. Here we show the results of a study on the very early stage of the MgB2 film growth. We find that the root-mean-squared roughness and grain connectivity of ultrathin MgB2 films grown on C-terminated 6H-SiC($000\bar{1}$) substrate is much better than those on Si-terminated substrate. The result provides a simple solution to growing high-quality ultrathin MgB2 films for applications. [ABSTRACT FROM AUTHOR]

Drought stress is an important factor that severely affects crop yield and quality. Autophagy has a crucial role in the responses to abiotic stresses. In this study, we explore TaNBR1 in response to drought stress. Expression of the TaNBR1 gene was strongly induced by NaCl, PEG, and abscisic acid treatments. The TaNBR1 protein is localized in the Golgi apparatus and autophagosome. Transgenic Arabidopsis plants overexpressing TaNBR1 exhibited reduced drought tolerance. When subjected to drought stress, compared to the wild-type (WT) lines, the transgenic overexpressing TaNBR1 plants had a lower seed germination rate, relative water content, proline content, and reduced accumulation of antioxidant enzymes, i.e., superoxide dismutase, peroxidase, and catalase, as well as higher chlorophyll losses, malondialdehyde contents, and water loss. The transgenic plants overexpressing TaNBR1 produced much shorter roots in response to mannitol stress, in comparison to the WT plants, and they exhibited greater sensitivity to abscisic acid treatment. The expression levels of the genes related to stress in the transgenic plants were affected in response to drought stress. Our results indicate that TaNBR1 negatively regulates drought stress responses by affecting the expression of stress-related genes in Arabidopsis. [ABSTRACT FROM AUTHOR]

Objective. To explore the application value of ultrasound image based on back propagation (BP) neural network algorithm in knee osteoarthritis (KOA) and evaluate the application effect and value of ultrasound image technology based on the BP neural network in the diagnosis of knee osteoarthritis cartilage lesions, 98 patients who were admitted to our hospital were diagnosed with KOA and had undergone arthroscopic soft tissue examinations were randomly selected. According to whether image processing was performed, the ultrasound images of all patients were divided into two groups. The control group was image before processing, and the experimental group was image after processing optimization. The consistency of the inspection results of the ultrasound images before and after the processing with the arthroscopy results was compared. The results showed that the staging accuracy of the control group was 68.3% and that of the experimental group was 76.9%. The accuracy of staging cartilage degeneration of the experimental group was higher than that of the control group, and the difference was not remarkable (P > 0.05). The kappa coefficient of the experimental group was 0.61, and that of the control group was 0.40. The kappa coefficient of the experimental group was higher than that of the control group, and the difference was significant (P < 0.05). Conclusion. The inspection effect of the ultrasound image processed by the BP neural network was superior to that of the conventional ultrasound image. It reflected the good adoption prospect of neural networks in image processing. [ABSTRACT FROM AUTHOR]

Molecular mechanisms of how constant temperatures affect flowering time have been largely characterized in the model plant Arabidopsis thaliana; however, the effect of natural daily variable temperature outside laboratories is only partly explored. Several flowering genes have been shown to play important roles in temperature responses, including PHYTOCHROME‐INTERACTING FACTOR 4 (PIF4) and FLOWERING LOCUS C (FLC), the two genes encoding for the transcription factors (TFs) that act antagonistically to regulate flowering time by activating and repressing floral integrator FLOWERING LOCUS T (FT), respectively. In this study, we have taken a multidisciplinary approach to explore the contribution of PIF4 to the early flowering observed in the daily variable temperature (VAR) and to broaden its transcriptional network using publicly available transcriptomic data. We observed early flowering in the natural accessions Col‐0, C24 and their late flowering hybrid C24xCol grown under VAR, as compared with a constant temperature (CON). The loss‐of‐function mutation of PIF4 exhibits later flowering in VAR in both the Col‐0 parent and the C24xCol hybrid, suggesting that PIF4, at least in part, contributes to acceleration of flowering in the VAR condition. To investigate the interplay between PIF4 and its flowering regulator counterparts, FLC and FT, we performed transcriptional analyses and found that VAR increased PIF4 transcription at the end of the day when temperature peaked at 32°C, when FT transcription was also elevated. On the other hand, we observed a decrease in FLC transcription in the 4‐week‐old plants grown in VAR, as well as in the plants with PIF4 overexpression grown in CON. These results raise a possibility that PIF4 might also regulate FT indirectly through the repression of FLC, in addition to the well‐characterized direct control of PIF4 over FT. To further expand our view on the PIF4‐orientated flowering gene network in response to temperature changes, we have constructed a coexpression–transcriptional regulatory network by combining publicly available transcriptomic data and gene regulatory interactions of PIF4 and its closely related flowering genes, PIF5, FLC, and ELF3. The network model reveals conserved and tissue‐specific regulatory functions, which are useful for confirming as well as predicting the functions and regulatory interactions between these key flowering genes. [ABSTRACT FROM AUTHOR]

Preclinical studies show improved prediction of treatment outcome using [ROS] rx than light fluence rate or PDT dose. We demonstrate ROSED in a clinical setting. Explicit dosimetry of light fluence, photosensitizer concentration, and oxygen concentration is used to quantify the reactive oxygen species explicit dosimetry (ROSED) during Photofrin-mediated pleural PDT. Light fluence and photosensitizer concentration were measured by a customized multi-channel PDT dose dosimeter system. Diffuse correlation spectroscopy (DCS) contact probes were sutured to the pleural cavity wall after surgical resection of pleural mesothelioma tumor to monitor tissue blood flow (BFI) during intraoperative PDT treatment. Tissue oxygen concentration can be determined by utilizing tumor blood flow measured by DCS. Large inter- and intra-patient heterogeneities in [ROS] rx were observed although an identical light dose of 60 J/cm2 was prescribed to all patients. This study summarizes the current results of ROSED for a Phase II pleural PDT clinical trial. [ABSTRACT FROM AUTHOR]

Multispectral singlet oxygen dosimetry (MSOLD) provides a mean for direct detection of singlet oxygen, responsible for tumor kill for type II PDT. An InGaAs spectrometer or an InGaAs detector coupled with to narrow beam filters (1200, 1240, 1250, 1270, 1300 nm) via 1 mm optical fibers are used to measure singlet oxygen (SO) luminescent spectrum in in-vitro and in-vivo conditions. The spectrum, after fitted to a phosphorescence background a gaussian function for the singlet oxygen peak, is used to determine the singlet oxygen (SO) emission signal. The MSOLD signal is then compared with the singlet oxygen explicit dosimetry (SOED) results, based on direct measurements of light fluence (rate), Photofrin concentration, and tissue oxygenation concentration. MSOLD signal is affected by tissue absorption and scattering and is increasing with increasing Photofrin concentration and light fluence rate. MSOLD is feasible in vitro and in vivo for detecting SO directly. [ABSTRACT FROM AUTHOR]

Mitogens trigger cell division in animals. In plants, cytokinins, a group of phytohormones derived from adenine, stimulate cell proliferation. Cytokinin signaling is initiated by membrane-associated histidine kinase receptors and transduced through a phosphorelay system. We show that in the Arabidopsis shoot apical meristem (SAM), cytokinin regulates cell division by promoting nuclear shuttling of Myb-domain protein 3R4 (MYB3R4), a transcription factor that activates mitotic gene expression. Newly synthesized MYB3R4 protein resides predominantly in the cytoplasm. At the G2-to-M transition, rapid nuclear accumulation of MYB3R4— consistent with an associated transient peak in cytokinin concentration—feeds a positive feedback loop involving importins and initiates a transcriptional cascade that drives mitosis and cytokinesis. An engineered nuclear-restricted MYB3R4 mimics the cytokinin effects of enhanced cell proliferation and meristem growth. [ABSTRACT FROM AUTHOR]

Summary: Breeding for disease resistance is the most effective strategy to control diseases, particularly with broad‐spectrum disease resistance in many crops. However, knowledge on genes and mechanism of broad‐spectrum resistance and trade‐off between defence and growth in crops is limited. Here, we show that the rice copine genes OsBON1 and OsBON3 are critical suppressors of immunity. Both OsBON1 and OsBON3 changed their protein subcellular localization upon pathogen challenge. Knockdown of OsBON1 and dominant negative mutant of OsBON3 each enhanced resistance to rice bacterial and fungal pathogens with either hemibiotrophic or necrotrophic lifestyles. The defence activation in OsBON1 knockdown mutants was associated with reduced growth, both of which were largely suppressed under high temperature. In contrast, overexpression of OsBON1 or OsBON3 decreased disease resistance and promoted plant growth. However, neither OsBON1 nor OsBON3 could rescue the dwarf phenotype of the Arabidopsis BON1 knockout mutant, suggesting a divergence of the rice and Arabidopsis copine genes. Our study therefore shows that the rice copine genes play a negative role in regulating disease resistance and their expression level and protein location likely have a large impact on the balance between immunity and agronomic traits. [ABSTRACT FROM AUTHOR]

Lipids and lipid metabolites play important roles in plant-microbe interactions. Despite the extensive studies of lipases in lipid homeostasis and seed oil biosynthesis, the involvement of lipases in plant immunity remains largely unknown. In particular, GDSL esterases/lipases, characterized by the conserved GDSL motif, are a subfamily of lipolytic enzymes with broad substrate specificity. Here, we functionally identified two GDSL lipases, OsGLIP1 and OsGLIP2, in rice immune responses. Expression of OsGLIP1 and OsGLIP2 was suppressed by pathogen infection and salicylic acid (SA) treatment. OsGLIP1 was mainly expressed in leaf and leaf sheath, while OsGLIP2 showed high expression in elongating internodes. Biochemical assay demonstrated that OsGLIP1 and OsGLIP2 are functional lipases that could hydrolyze lipid substrates. Simultaneous down-regulation of OsGLIP1 and OsGLIP2 increased plant resistance to both bacterial and fungal pathogens, whereas disease resistance in OsGLIP1 and OsGLIP2 overexpression plants was significantly compromised, suggesting that both genes act as negative regulators of disease resistance. OsGLIP1 and OsGLIP2 proteins mainly localize to lipid droplets and the endoplasmic reticulum (ER) membrane. The proper cellular localization of OsGLIP proteins is indispensable for their functions in immunity. Comprehensive lipid profiling analysis indicated that the alteration of OsGLIP gene expression was associated with substantial changes of the levels of lipid species including monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG). We show that MGDG and DGDG feeding could attenuate disease resistance. Taken together, our study indicates that OsGLIP1 and OsGLIP2 negatively regulate rice defense by modulating lipid metabolism, thus providing new insights into the function of lipids in plant immunity. [ABSTRACT FROM AUTHOR]

Summary Programmed cell death (PCD) and immunity in plants are tightly controlled to promote antimicrobial defense while preventing autoimmunity. However, the mechanisms contributing to this immune homeostasis are poorly understood. Here, we isolated a rice mutant ebr1 ( enhanced blight and blast resistance 1 ) that shows enhanced broad-spectrum bacterial and fungal disease resistance, but displays spontaneous PCD, autoimmunity, and stunted growth. EBR1 encodes an E3 ubiquitin ligase that interacts with OsBAG4, which belongs to the BAG (Bcl-2-associated athanogene) family that functions in cell death, growth arrest, and immune responses in mammals. EBR1 directly targets OsBAG4 for ubiquitination-mediated degradation. Elevated levels of OsBAG4 in rice are necessary and sufficient to trigger PCD and enhanced disease resistance to pathogenic infection, most likely by activating pathogen-associated molecular patterns-triggered immunity (PTI). Together, our study suggests that an E3-BAG module orchestrates innate immune homeostasis and coordinates the trade-off between defense and growth in plants. [ABSTRACT FROM AUTHOR]

Wheat starch development is a complex process and is markedly difference by changes in spikelet spatial position. The present study deals with endosperm starch granule distribution and spatial position during filling development. The study was conducted with pure starch isolated from wheat (Triticum aestivum L.), Jimai20 and Shannong1391, at 7–35 days after anthesis (DAA). The results showed that grain number, spikelet weight and grain weight per spikelet in different spatial position showed parabolic changes. Upper spikelets had highest starch and amylose content followed by basal spikelets, then middle spikelets. The paper also suggested the volume percents of B-type and A-type granule in grain of middle spikelets were remarkably higher and lower than those of basal and upper spikelets, respectively. However, no significant difference occurred in the number percents of the two type granule. The ratio of amylase to amylopectin was positively correlated with the volume proportion of 22.8–42.8 µm, but was negatively related to the volume proportion of <9.9 µm. The results indicated that the formation and distribution of starch granules were affected significantly by spikelet position, and grains at upper and basal spikelet had the potential of increasing grain weight through increasing the volume of B-type granules. [ABSTRACT FROM AUTHOR]

The article discusses how DELLA protein complex controls the arbuscular mycorrhizal symbiosis in plants. Topics of discussion included were SLR1/DELLA, a repressor of gibberellic acid (GA) signaling, inhibition of mycorrhizal colonization by GA treatment in Pisum sativum, Oryzae sativa and mycorrhizal associated gene expression. Other topics were nutrient responses, light perception and signaling of several interacting hormones including auxin, ethylene and abscisic acid by DELLA.