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Inorganic phosphate (Pi) is an essential macronutrient required for many fundamental processes in plants, including photosynthesis and respiration, as well as nucleic acid, protein, and membrane phospholipid synthesis. The huge use of Pi-containing fertilizers in agriculture demonstrates that the soluble Pi levels of most soils are suboptimal for crop growth. This review explores recent advances concerning the understanding of adaptive metabolic processes that plants have evolved to alleviate the negative impact of nutritional Pi deficiency. Plant Pi starvation responses arise from complex signaling pathways that integrate altered gene expression with post-transcriptional and post-translational mechanisms. The resultant remodeling of the transcriptome, proteome, and metabolome enhances the efficiency of root Pi acquisition from the soil, as well as the use of assimilated Pi throughout the plant. We emphasize how the up-regulation of high-affinity Pi transporters and intra- and extracellular Pi scavenging and recycling enzymes, organic acid anion efflux, membrane remodeling, and the remarkable flexibility of plant metabolism and bioenergetics contribute to the survival of Pi-deficient plants. This research field is enabling the development of a broad range of innovative and promising strategies for engineering phosphorus-efficient crops. Such cultivars are urgently needed to reduce inputs of unsustainable and non-renewable Pi fertilizers for maximum agronomic benefit and long-term global food security and ecosystem preservation. [ABSTRACT FROM AUTHOR]

This article deals with the self-insider, i. e. the possible creation of the inside information by a person and its (abusive) exploitation. It describes the situation in Germany and in Italy and provides a taxonomy of the several cases of self-insider. The article then analyzes the case law of the ECJ and the MAR regulatory provisions for justifying/neglecting the existence of the self-insider (Article 9.5 and 9.6 MAR). Given the unclear regulatory answer regarding its sanctionability, the article proposes, based on the economics of MAR, a law and economics reason of why the self-insider sometime should be sanctioned, by describing it as a peculiar monopolistic behavior able to distort investors' confidence and market integrity. Finally, the article suggests that the European legislator should explicitly deal with the problem. [ABSTRACT FROM AUTHOR]

Intense Asian summer monsoon rainfall responds to high boreal summer insolation and environmental feedbacks in the early and middle Holocene. However, it is unclear what role of the Asian summer monsoon strength might have played for the heterogeneous wetness pattern in northern China. Here, we report two wet periods in the early and middle Holocene by paleosol, lacustrine, and peat stratigraphies in the southeast Mu Us Desert, and that early-Holocene wetness records are common and seen in valleys and missing from valley walls while mid-Holocene wetness records are found everywhere in the region. The preliminary analysis of the stable carbon isotopic composition (δ13C) of soil carbonate and organic carbon from a riverine dune–paleosol sequence in a river valley reveals that wet springs/falls with dry summers frequently prevailed in the early Holocene, while wet summers with dry springs/falls became predominant in the middle Holocene. Strong-wind and low-temperature springs and falls on valley walls and uplands cause eolian sedimentation faster than soil formation but weak-wind and warmer-soil temperature in valleys facilitate vegetation metabolism and thus soil formation. Warm summer rainfall with no strong northwesterly wind causes paleosol, lacustrine and peat formation either in valleys or on uplands. The early-Holocene heterogeneous and middle-Holocene uniform wetness records are indeed controlled by seasonal hydroclimate conditions but not a single factor of summer monsoon rainfall strength in the southeast Mu Us Desert. [ABSTRACT FROM AUTHOR]

In this paper, the molecular dynamics simulation method was used to establish the MD model for diamond cutting iron. The cutting process was simulated, and the change rules of temperature, cutting stress and radial distribution function with timestep were analysed. The results show that: As the cutting progresses, the temperature will increase gradually, the cutting stress fluctuates around 50,000 bars, and the wear mechanism of tool is analysed form a microscopic perspective; By adjusting the posture of the tool, the rake angle and the flank angle are changed, and the size of the thermostat layer and boundary layer are adjusted at the same time, which reduces the impact of non-Newton atoms on the workpiece; The change rules of temperature and cutting stress under different rake angle and flank angle conditions are analysed, and the minimum cutting stress is obtained when the rake angle is 15 degrees; By prefabricating a crack on the flank face, the change rule of the crack edge stress is studied. It is found that due to the occurrence of crack, the contact area between the tool and the workpiece is reduced, and there is obvious stress concentration at the edge of the crack. [ABSTRACT FROM AUTHOR]

Phosphate is an essential nutrient for life and is a critical component of bone formation, a major signaling molecule, and structural component of cell walls. Phosphate is also a component of high-energy compounds (i.e., AMP, ADP, and ATP) and essential for nucleic acid helical structure (i.e., RNA and DNA). Phosphate plays a central role in the process of mineralization, normal serum levels being associated with appropriate bone mineralization, while high and low serum levels are associated with soft tissue calcification. The serum concentration of phosphate and the total body content of phosphate are highly regulated, a process that is accomplished by the coordinated effort of two families of sodium-dependent transporter proteins. The three isoforms of the SLC34 family (SLC34A1--A3) show very restricted tissue expression and regulate intestinal absorption and renal excretion of phosphate. SLC34A2 also regulates the phosphate concentration in multiple lumen fluids including milk, saliva, pancreatic fluid, and surfactant. Both isoforms of the SLC20 family exhibit ubiquitous expression (with some variation as to which one or both are expressed), are regulated by ambient phosphate, and likely serve the phosphate needs of the individual cell. These proteins exhibit similarities to phosphate transporters in nonmammalian organisms. The proteins are nonredundant as mutations in each yield unique clinical presentations. Further research is essential to understand the function, regulation, and coordination of the various phosphate transporters, both the ones described in this review and the phosphate transporters involved in intracellular transport. [ABSTRACT FROM AUTHOR]

Background: The noggin protein encoded by the NOG gene can interfere with the binding of bone morphogenetic protein to its receptor, thus affecting bone and joint development. The symptoms include abnormal skeletal development and conductive deafness. Methods: In a retrospective study, clinical data of the proband and her family members, including 8 people and 50 healthy normal controls, were collected. Second-generation sequencing was performed on peripheral blood samples from them. Results: The sequencing analysis indicated that in the proband, the NOG gene had a c.532T > C, p.C178R (cytosine deletion, NM_005450.6:c.532T > C), leading to an amino acid change. The proband's father, grandmother, second sister, and third sister also had this mutation, whereas family members with normal phenotypes did not have the mutation. Conclusion: Analysis of this family showed that the novel presentation of the c.532T > C, p.C178R mutation in the NOG gene resulted in syndrome-type autosomal dominant inheritance reflected in a mild clinical phenotype, which is of great importance for further studies of the clinical phenotype and pathogenesis of stapes sclerosis. [ABSTRACT FROM AUTHOR]

Disseminated disease from non-typhoidal Salmonella enterica strains results in >20% mortality globally. Barriers to effective treatment include emerging multidrug resistance, antibiotic treatment failure, and risk factors such as malnutrition and related micronutrient deficiencies. Individuals in sub-Saharan Africa are disproportionately affected by non-typhoidal S. enterica bloodstream infections. To inform a clinical trial in people, we investigated vitamin A as a treatment in the context of antibiotic treatment failure in a mouse model of vitamin A deficiency. Vitamin A-deficient (VAD) mice exhibited higher systemic bacterial levels with a multidrug-resistant clinical isolate in comparison to mice on a control diet. Sex-specific differences in vitamin A deficiency and disseminated infection with S. enterica serotype Typhimurium (S. Typhimurium) were observed. VAD male mice had decreased weight gain compared to control male mice. Further, infected VAD male mice had significant weight loss and decreased survival during the course of infection. These differences were not apparent in female mice. In a model of disseminated S. Typhimurium infection and antibiotic treatment failure, we assessed the potential of two consecutive doses of vitamin A in alleviating infection in male and female mice on a VAD or control diet. We found that subtherapeutic antibiotic treatment synergized with vitamin A treatment in infected VAD male mice, significantly decreasing systemic bacterial levels, mitigating weight loss and improving survival. These results suggest that assessing vitamin A as a therapy during bacteremia in malnourished patients may lead to improved health outcomes in a subset of patients, especially in the context of antibiotic treatment failure. Author summary: Non-typhoidal Salmonella serotypes generally cause diarrhea in people. However, there are certain factors that make people at risk of developing a more severe infection where the bacteria can enter the blood and cause fever and whole-body symptoms. Patients with this infection are usually hospitalized, and about one in five patients do not survive. The factors that make this bloodstream infection possible include pathogen features like resistance to antibiotics and patient factors like a malnourished state. Better treatments are needed. In this study, the authors assess vitamin A as a treatment during antibiotic treatment failure in a mouse model. Vitamin A-deficient male mice have better outcomes with vitamin A and antibiotic co-therapy, whereas female mice do not benefit. Despite similar levels of bacteria causing infection systemically, female mice show better outcomes in terms of weight loss and survival than male mice overall. This research provides evidence that a clinical study assessing vitamin A as a treatment in people could lead to improved survival for malnourished patients presenting with severe bloodstream infection. [ABSTRACT FROM AUTHOR]

In this paper, we proposed a light field resampling method for generating elemental image array (EIA) of integral imaging. The proposed method can break through the constraints between parameters of traditional integral imaging record device and display device and allow to generate a new set of EIA suited to be displayed in an integral imaging display device with arbitrary parameters from any given recorded EIA. Three‐dimensional display results show the correctness and superiority of the proposed method. [ABSTRACT FROM AUTHOR]

Background: Wound healing is a complex biological process comprised of a series of sequential events aiming to repair injured tissue. Adult mesenchymal stem cells (MSCs) have been used in cellular therapy in preclinical animal studies; a promising source of MSCs is adipose tissue (AT). In this paper, we evaluated the clinical value and safety of the application of cultured allogenic MSCs from AT for acute and chronic skin wound healing in a canine model. Methods: Twenty-four dogs of different breeds between 1 and 10 years of age with acute and chronic wounds were studied. Morphology of the wounded skin was monitored for changes over time via serial photographs and histopathological studies. Results: The percentage of the wounds that exhibited contraction and re-epithelialization were significantly different between wounds treated with adipose mesenchymal stem cells (ASCs) and control wounds; this effect was observed in both acute and chronic conditions. At 90 days, re-epithelization of acute and chronic wounds reached more than 97%. Histopathological study revealed a reduction in inflammatory infiltrate and the presence of multiple hair follicles on day 7 after treatment with ASCs, promoting epidermal and dermal regeneration. To guarantee the safety of our treatment, we determined the serum levels of cytokine markers in our patients. ASC treatment upregulated granulocyte-macrophage colony stimulating factor (GM-CSF) at the gene level, which may contribute to the recruitment of cells that participate in skin repair to the site of injury. Conclusions: The development of an allogenic ASC therapy to improve wound healing in a canine model could have a clinical impact in human treatment. [ABSTRACT FROM AUTHOR]

Background: Characterization of physiological parameters of the aging brain, such as perfusion and brain metabolism, is important for understanding brain function and diseases. Aging studies on human brain have mostly been based on the cross-sectional design, while the few longitudinal studies used relatively short follow-up time compared to the lifespan. Objectives: To determine the longitudinal time courses of cerebral physiological parameters across the adult lifespan in mice. Methods: The present work examined longitudinal changes in cerebral blood flow (CBF), cerebral venous oxygenation (Yv), and cerebral metabolic rate of oxygen (CMRO2) using MRI in healthy C57BL/6 mice from 3 to 20 months of age. Each mouse received 16 imaging sessions at an ~1-month interval. Results: Significant increases with age were observed in CBF (p = 0.017) and CMRO2 (p < 0.001). Meanwhile, Yv revealed a significant decrease (p = 0.002) with a non-linear pattern (p = 0.013). The rate of change was 0.87, 2.26, and −0.24% per month for CBF, CMRO2, and Yv, respectively. On the other hand, systemic parameters such as heart rate did not show a significant age dependence (p = 0.47). No white-matter-hyperintensities (WMH) were observed on the T2-weighted image at any age of the mice. Conclusion: With age, the mouse brain revealed an increase in oxygen consumption. This observation is consistent with previous findings in humans using a cross-sectional design and suggests a degradation of the brain's energy production or utilization machinery. Cerebral perfusion remains relatively intact in aged mice, at least until 20 months of age, consistent with the absence of WMH in mice. [ABSTRACT FROM AUTHOR]

In recent years, elliptical vibration cutting (EVC) has been proven as a promising technique to improve the cutting performance of brittle materials like silicon. However, the influence of vibration parameters on the machined surface quality has not been explored clearly. In this paper, molecular dynamics simulation was carried out to explore the machinable mechanism of silicon by EVC. Firstly, the difference in material removal performance between ordinary cutting (OC) and EVC was discussed. Then, the influence of two critical parameters in EVC, i.e., the vibration amplitude in the depth of cut (DOC) direction and the nominal DOC, on the machined surface quality was explored in detail. The simulation results demonstrate that the vibration amplitude in the DOC direction has a significant influence on the compressive stress and tensile stress distribution, which affects the phase transition and chip pulling-up motion in the EVC process. Based on the simulation results and previous experimental achievements, the high-quality surface can be obtained when the amplitude ratio in the nominal cutting/DOC direction is about 3.5. Furthermore, when the nominal DOC is increased, although the variation of tensile stress is quite small, the increased chip pulling-up distance is responsible for brittle fracture on the machined surface. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the imaging quality and diagnostic performance of fast spin echo diffusion‐weighted imaging with periodically rotated overlapping parallel lines with enhanced reconstruction (FSE‐PROP‐DWI) in distinguishing parotid pleomorphic adenoma (PMA) from Warthin tumor (WT). This retrospective study enrolled 44 parotid gland tumors from 34 patients, including 15 PMAs and 29 WTs with waived written informed consent. All participants underwent 1.5 T diffusion‐weighted imaging including FSE‐PROP‐DWI and single‐shot echo‐planar diffusion‐weighted imaging (SS‐EP‐DWI). After imaging resizing and registration among T2WI, FSE‐PROP‐DWI and SS‐EP‐DWI, imaging distortion was quantitatively analyzed by using the Dice coefficient. Signal‐to‐noise ratio and contrast‐to‐noise ratio were qualitatively evaluated. The mean apparent diffusion coefficient (ADC) of parotid gland tumors was calculated. Wilcoxon signed‐rank test was used for paired comparison between FSE‐PROP‐DWI versus SS‐EP‐DWI. Mann–Whitney U test was used for independent group comparison between PMAs versus WTs. Diagnostic performance was evaluated by receiver operating characteristics curve analysis. P < 0.05 was considered statistically significant. The Dice coefficient was statistically significantly higher on FSE‐PROP‐DWI than SS‐EP‐DWI for both tumors (P < 0.005). Mean ADC was statistically significantly higher in PMAs than WTs on both FSE‐PROP‐DWI and SS‐EP‐DWI (P < 0.005). FSE‐PROP‐DWI and SS‐EP‐DWI successfully distinguished PMAs from WTs with an AUC of 0.880 and 0.945, respectively (P < 0.05). Sensitivity, specificity, positive predictive value, negative predictive value and accuracy in diagnosing PMAs were 100%, 69.0%, 62.5%, 100% and 79.5% for FSE‐PROP‐DWI, and 100%, 82.8%, 75%, 100% and 88.6% for SS‐EP‐DWI, respectively. FSE‐PROP‐DWI is useful to distinguish parotid PMAs from WTs with less distortion of tumors but lower AUC than SS‐EP‐DWI. [ABSTRACT FROM AUTHOR]

Mesoporous Ca1−xLn3 +xMnO3 (Ln3+ = Sm, Ce, La; x = 0, 0.1) nanoparticles were prepared by sol–gel hydrothermal method followed by annealing under oxygen atmosphere at 950 °C. The systematic analysis revealed that due to the influence of lanthanides substitution, significant changes were occurring on the electrical and thermoelectric properties of the material. The synthesized nanopowders were characterized by XRD, Raman analysis, SEM with EDAX, HRTEM and thermoelectric measurement. Structural analysis confirmed the orthorhombic perovskite structure without distortions and the cell volume increased with a rise in the ionic radius of the Ln3+ ions. Microstructure and EDAX analysis demonstrated the grain size and stoichiometry of all the samples. HRTEM analysis is used to measure the size and shape of the nanoparticles. The physical properties of Ca0.9Ln3+0.1MnO3 nanoparticles exhibit metallic behavior with increasing temperature whereas undoped CaMnO3 shows semiconducting behavior. The electrical and thermoelectric measurements proved that Ca0.9Sm0.1MnO3 nanoparticle showed high Seebeck coefficient value, large electrical resistivity, and significant power factor, indicating a potential n-type thermoelectric material at elevated temperature. [ABSTRACT FROM AUTHOR]

Background: The family of NAC proteins (NAM, ATAF1/2, and CUC2) represent a class of large plant-specific transcription factors. However, identification and functional surveys of NAC genes of tomato (Solanum lycopersicum) remain unstudied, despite the tomato genome being decoded for several years. This study aims to identify the NAC gene family and investigate their potential roles in responding to Al stress. Results: Ninety-three NAC genes were identified and named in accordance with their chromosome location. Phylogenetic analysis found SlNACs are broadly distributed in 5 groups. Gene expression analysis showed that SlNACs had different expression levels in various tissues and at different fruit development stages. Cycloheximide treatment and qRT-PCR analysis indicated that SlNACs may aid regulation of tomato in response to Al stress, 19 of which were significantly up- or down-regulated in roots of tomato following Al stress. Conclusion: This work establishes a knowledge base for further studies on biological functions of SlNACs in tomato and will aid in improving agricultural traits of tomato in the future. [ABSTRACT FROM AUTHOR]

An unmodified polypropylene (PP) model and a modified model with 2% nano-silicon dioxide content were built initially, and then the mechanical parameters of the two models were compared by molecular dynamics simulation. The results show that the modulus of the modified model are larger than those of the unmodified model, and the ductility of both models is stable. The yield point of the modified model was increased by 8.5% at 25°C and 14.2% at 100°C compared with that of the unmodified model, respectively. Its Young's modulus is also increased. The main mechanism is that the addition of nanoparticles results in the decrease in the free volume of PP molecules, and the interaction between the strong polar –OH groups and the H atoms in a large number of –CH3 groups in PP molecules increases the intermolecular force in the whole model, which leads to the improvement of mechanical properties. Higher temperature leads to the intensification of molecular motion, which increases the distance between molecules, decreases the cohesive energy and reduces the mechanical properties of the model. The results of this paper can provide some reference for further research on the improvement of mechanical properties of nano-doped modified materials. [ABSTRACT FROM AUTHOR]

Tanshinones are major secondary metabolites in Salvia miltiorrhiza Bunge, the traditional Chinese medicinal plant Danshen. Increasing the production of tanshinones is important because of their significant economic value in human medicine, for the treatment of cardiovascular and cerebrovascular diseases and for their anti-tumor properties. Phosphate (Pi) starvation can change secondary metabolism in plants. MYB transcription factors (TFs) have been reported to be involved in both Pi starvation signaling and secondary metabolism regulation, enabling plants to build a relationship between the Pi starvation signal and secondary metabolism. In the present study, a nucleus-located R2R3 MYB TF, SmMYB98b, was found in S. militorrhiza. SmMYB98b was shown to belong to subgroup 20 of R2R3-MYB TFs, and expression could be induced by low-Pi conditions. The overexpression of SmMYB98b in S. militorrhiza hairy roots stimulated tanshinone accumulation. Plants overexpressing SmMYB98b exhibited Pi-starvation responses, such as decreased Pi concentration and activation of genes inducible by phosphate starvation, whereas transgenic plants with the SmMYB98b-RNA interference (RNAi) construct showed the opposite phenotype. In summary, the present study highlighted the role of SmMYB98b as a regulator of tanshinone biosynthesis and its potential function in Pi-starvation signaling. These results might have wider implications for studying the crosstalk between Pi stress responses and secondary metabolism pathways in plants. Key message: This study highlights the role of SmMYB98b as a positive regulator of tanshinone biosynthesis and its potential function in Pi-starvation signaling in Salvia miltiorrhiza. [ABSTRACT FROM AUTHOR]

During single-point diamond turning of hard and brittle materials, tool wear is a dominant factor that influences machinability. In the wear process, micro grooves on the flank face is an important character of tool wear, which leads to the formation of subcutting edges and the ductile to brittle transition. In this paper, classical molecular dynamic simulations of nanometric cutting of silicon by a diamond tool with V-shape grooves were carried out to explore the effect of groove geometry on the workpiece and tool integrity. The evolution of tool wear and machined surface integrity was discussed. Simulation result shows that grooves have a significant influence on the stress and temperature distributions of the tool, which has a great influence on tool deterioration. Grooves with sharp edges will lead to severe tool wear and bring deep subsurface damage of the machined surface. However, the subsurface damage of the machined surface can be restrained with blunt grooves since the pressure is reduced. With a comprehensive understanding and controlling of groove, tool wear can be suppressed and high-quality surface can be achieved. [ABSTRACT FROM AUTHOR]

Tabletop three‐dimensional (3D) display is an attractive display technology that allows multiple individuals around the table to view the reconstructed 3D objects simultaneously, which can be applied to a variety of application scenarios such as desktop conference and board games. In this review paper, the tabletop true 3D display has been characterized and classified into four categories based on the technologies of light field display, integral imaging, and volumetric 3D and holographic 3D displays. Moreover, the comparisons of these technologies are listed, and the prospect of the tabletop 3D display is discussed. [ABSTRACT FROM AUTHOR]

Objective: The goal of this work is to analyze the influence of the distributions and dimensions of the coil elements and to present a method for improving the performance of the matrix gradient coil., Methods: Three typical models (five structures in total) are presented, and a double-layer biplanar matrix gradient coil is used to install coil elements. Two metrics, namely, the role of coil elements and mutual inductance between coil elements, are proposed to assess the performance of coil systems. An optimization approach to design matrix gradient coils is introduced based on analyzing the distributions and dimensions of coil elements. The flexibility of the magnetic field generation of the designed coil structure is demonstrated by generating full third-order spherical harmonic fields and different oblique gradient fields., Results: Matrix gradient coils with suitable distributions are capable of generating target magnetic fields. The role of coil elements quantitatively illustrates that the coil elements have different impacts on generating magnetic fields. Increasing the coil element dimension within a certain range can reduce the mutual inductance between coil elements and improve the performance of the coil system. The designed novel double-layer biplanar matrix gradient coil achieves an acceptable performance in generating different magnetic fields., Conclusions: The proposed metrics can provide theoretical support for designing matrix gradient coils and evaluating their performance. The role of coil elements contributes to analyzing the distributions of coil elements to decrease the number of coil elements and power amplifiers. The mutual inductance between coil elements can be a reference for designing the dimensions of coil elements., (© 2022. The Author(s), under exclusive licence to European Society for Magnetic Resonance in Medicine and Biology (ESMRMB).)

Background: Quantification of cerebral blood flow (CBF) with [ 15 O]H 2 O-positron emission tomography (PET) requires arterial sampling to measure the input function. This invasive procedure can be avoided by extracting an image-derived input function (IDIF); however, IDIFs are sensitive to partial volume errors due to the limited spatial resolution of PET., Purpose: To present an alternative hybrid PET/MR imaging of CBF (PMRFlow IDIF ) that uses phase-contrast (PC) MRI measurements of whole-brain (WB) CBF to calibrate an IDIF extracted from a WB [ 15 O]H 2 O time-activity curve., Study Type: Technical development and validation., Animal Model: Twelve juvenile Duroc pigs (83% female)., Population: Thirteen healthy individuals (38% female)., Field Strength/sequences: 3 T; gradient-echo PC-MRI., Assessment: PMRFlow IDIF was validated against PET-only in a porcine model that included arterial sampling. CBF maps were generated by applying PMRFlow IDIF and two previous PMRFlow methods (PC-PET and double integration method [DIM]) to [ 15 O]H 2 O-PET data acquired from healthy individuals., Statistical Tests: PMRFlow and PET CBF measurements were compared with regression and correlation analyses. Paired t-tests were performed to evaluate differences. Potential biases were assessed using one-sample t-tests. Reliability was assessed by intraclass correlation coefficients. Statistical significance: α  = 0.05., Results: In the animal study, strong agreement was observed between PMRFlow IDIF (average voxel-wise CBF, 58.0 ± 16.9 mL/100 g/min) and PET (63.0 ± 18.9 mL/100 g/min). In the human study, PMRFlow DIM (y = 1.11x - 5.16, R 2  = 0.99 ± 0.01) and PMRFlow PC-PET (y = 0.87x + 3.82, R 2  = 0.97 ± 0.02) performed similarly to PMRFlow IDIF, and CBF was within the expected range (eg, 49.7 ± 7.2 mL/100 g/min for gray matter)., Data Conclusion: Accuracy of PMRFlow IDIF was confirmed in the animal study with the primary source of error attributed to differences in WB CBF measured by PC MRI and PET. In the human study, differences in CBF from PMRFlow IDIF , PMRFlow DIM , and PMRFlow PC-PET were due to the latter two not accounting for blood-borne activity., Level of Evidence: 2 TECHNICAL EFFICACY STAGE: 1., (© 2022 International Society for Magnetic Resonance in Medicine.)

Phosphorus (P) is an essential nutrient for plant growth and development. Phosphate (Pi) fertilizer supply is an effective way to improve crop yield. However, generally, less than 25% of the applied Pi is taken up by crops. Therefore, it is urgent to improve crop P use efficiency. The overall P use efficiency includes processes of P acquisition from soil, translocation from root to shoot, allocation, utilization, and remobilization within plant; each process can be developmentally and environmentally regulated. In this review, we summarize recent studies on molecular mechanisms and regulatory pathways involved in rice root Pi acquisition, Pi transportation from root to shoot, and allocation and remobilization of Pi within plant tissues. The possible strategies for improving crop P use efficiency are also discussed. [ABSTRACT FROM AUTHOR]

Phase-contrast mapping (PCM) magnetic resonance imaging (MRI) provides easy-access non-invasive quantification of global cerebral blood flow (gCBF) but its accuracy in altered perfusion states is not established. We aimed to compare paired PCM MRI and 15O-H2O positron emission tomography (PET) measurements of gCBF in different perfusion states in a single scanning session. Duplicate combined gCBF PCM-MRI and 15O-H2O PET measurements were performed in the resting condition, during hyperventilation and after acetazolamide administration (post-ACZ) using a 3T hybrid PET/MR system. A total of 62 paired gCBF measurements were acquired in 14 healthy young male volunteers. Average gCBF in resting state measured by PCM-MRI and 15O-H2O PET were 58.5 ± 10.7 and 38.6 ± 5.7 mL/100 g/min, respectively, during hyperventilation 33 ± 8.6 and 24.7 ± 5.8 mL/100 g/min, respectively, and post-ACZ 89.6 ± 27.1 and 57.3 ± 9.6 mL/100 g/min, respectively. On average, gCBF measured by PCM-MRI was 49% higher compared to 15O-H2O PET. A strong correlation between the two methods across all states was observed (R2 = 0.72, p < 0.001). Bland–Altman analysis suggested a perfusion dependent relative bias resulting in higher relative difference at higher CBF values. In conclusion, measurements of gCBF by PCM-MRI in healthy volunteers show a strong correlation with 15O-H2O PET, but are associated with a large and non-linear perfusion-dependent difference. [ABSTRACT FROM AUTHOR]

Reconstruction of the desert paleoclimate is important to understand the mechanisms that triggered and/or enhanced climate change. Through optically stimulated luminescence (OSL) dating, grain size, magnetic susceptibility, X-ray powder diffraction (XRD) and geochemical indicators, we provide a well-dated record of a sedimentary outcrop on the southeast margin of the Bardain Jaran Desert, Northwest China, during the last glacial period. Four Qz-OSL ages are obtained, 41.0±34 ka, 54.7±4.4 ka, 59.5±5.0 ka and 66.8±5.8 ka, corresponding to the depths of 35 cm, 70 cm, 150 cm and 200 cm respectively. Indicators like grain size, clay content, magnetic susceptibility, XRD and geochemical index (e.g. Sr, Ba, Sr/Ca) jointly indicate abrupt climate changes at the depth of 35 cm (age, ca. 41.0 ka) and 200 cm (age, ca. 67 ka). Namely, the 280 cm sedimentary outcrop perfectly records a warm wet climate stage, corresponding to the late Marine Isotope Stages (MIS) 4 to the early MIS 3. Besides, there is a trend of grain size increase after around 40 ka BP, which is most likely a signal of wind strength change. Our research supports that enhancing Siberian High pressure system during the late MIS 3 played a key role in NW East Asia climate evolution. [ABSTRACT FROM AUTHOR]

There is increasing interest in applying physiological MRI in neonates, based on the premise that physiological parameters may provide an early biomarker of neonatal brain health and injury. Two commonly used techniques are oxygen extraction fraction (OEF) measurement using T2‐relaxation‐under‐spin‐tagging (TRUST) MRI and cerebral blood flow measurement using phase‐contrast (PC) quantitative flow MRI, which collectively provide an assessment of the brain's oxygen consumption. However, prior research has only demonstrated proof of principle of these methods in neonates, without characterization or benchmarking of the techniques. This is because available time is limited in neonatal subjects, especially when scans are performed as add‐ons to clinical scans (typically less than 5 min). The work presented aims to examine the TRUST and PC MRI sequences systematically in normal neonates, through research‐dedicated scan sessions. A series of characterization and optimization studies were conducted in a total of 26 radiographically normal neonates on 3 T systems. Our results show that TRUST MRI at the superior sagittal sinus (SSS) provides an OEF measurement equivalent to that at the internal jugular vein (r = 0.80, n = 10), yet with shorter scan time. Lower resolution provided better precision in the TRUST measurement (p = 0.001, n = 9). Therefore, the preferred OEF measurement is to apply TRUST MRI at the SSS using a spatial resolution of 2.5 mm. For PC MRI, our results showed that non‐gated PC MRI yielded blood flow measurements comparable to those from the more time‐consuming gated approach in neonates (r = 0.89, n = 7). It was also found that blood flow could be overestimated by 18% when imaging resolution is larger than 0.3 mm (n = 7). Therefore, non‐gated PC MRI with a spatial resolution of 0.3 mm is recommended for neonatal applications. In conclusion, this study verifies consistency of neonatal brain oxygenation and flow measurements across acquisition schemes and points to optimal strategies in parameter selection when using these sequences. [ABSTRACT FROM AUTHOR]

Purpose: Effective removal of chemical‐shift artifacts in echo‐planar imaging (EPI) is a challenging problem especially with severe field inhomogeneity. This study aims to develop a reliable water/fat separation technique for point spread function (PSF) encoded EPI (PSF‐EPI) by using its intrinsic multiple echo‐shifted images. Theory and Methods: EPI with PSF encoding can achieve distortion‐free imaging and can be highly accelerated using the tilted‐CAIPI technique. In this study, the chemical‐shift encoding existing in the intermediate images with different time shifts of PSF‐EPI is used for water/fat separation, which is conducted with latest water/fat separation algorithms. The method was tested in T1‐weighted, T2‐weighted, and diffusion weighted imaging in healthy volunteers. Results: The ability of the proposed method to separate water/fat using intrinsic PSF‐EPI signals without extra scans was demonstrated through in vivo T1‐weighted, T2‐weighted, and diffusion weighted imaging experiments. By exploring different imaging contrasts and regions, the results show that this PSF‐EPI based method can separate water/fat and remove fat residues robustly. Conclusion: By using the intrinsic signals of PSF‐EPI for water/fat separation, fat signals can be effectively suppressed in EPI even with severe field inhomogeneity. This water/fat separation method for EPI can be extended to multiple image contrasts. The distortion‐free PSF‐EPI technique, thus, has the potential to provide anatomical and functional images with high‐fidelity and practical acquisition efficiency. [ABSTRACT FROM AUTHOR]

Diet composed of smaller particles can improve feed intake, digestibility, and animal growth or health, but in ruminant species can reduce rumination and buffering–the loss of which may inhibit fermentation and digestibility. However, the explicit effect of particle size on the rumen microbiota remains untested, despite their crucial role in digestion. We evaluated the effects of reduced particle size on rumen microbiota by feeding long-stem (loose) alfalfa hay compared to a ground and pelleted version of the same alfalfa in yearling sheep wethers during a two-week experimental period. In situ digestibility of the pelleted diet was greater at 48 h compared with loose hay; however, distribution of residual fecal particle sizes in sheep did not differ between the dietary treatments at any time point (day 7 or 14). Both average daily gain and feed efficiency were greater for the wethers consuming the pelleted diet. Observed bacterial richness was very low at the end of the adaptation period and increased over the course of the study, suggesting the rumen bacterial community was still in flux after two weeks of adaptation. The pelleted-hay diet group had a greater increase in bacterial richness, including common fibrolytic rumen inhabitants. The pelleted diet was positively associated with several Succiniclasticum, a Prevotella, and uncultured taxa in the Ruminococcaceae and Rickenellaceae families and Bacteroidales order. Pelleting an alfalfa hay diet for sheep does shift the rumen microbiome, though the interplay of diet particle size, retention and gastrointestinal transit time, microbial fermentative and hydrolytic activity, and host growth or health is still largely unexplored. [ABSTRACT FROM AUTHOR]

Aims: The selection and breeding of low grain-cadmium (Cd)-accumulating rices is a promising approach for reducing the Cd concentration in grains. A cadmium-safe rice line designated D62B (Oryza Sative L.) accumulated a low Cd concentration in brown rice for safe consumption (< 0.2 mg kg−1). D62B was a great potential breeding material with a weaker translocation capacity of Cd to shoot compared with common rice lines. A prior understanding of the Cd translocation mechanisms in D62B offered theoretical basis for breeding new low-Cd-accumulating rice cultivars in the future. Methods: A pot experiment was conducted to investigate the changes of non-protein thiols in shoot and root of D62B in comparison with a common rice line (Luhui17), and then the relationship between the Cd translocation via xylem and organic acids in xylem sap of two rice lines was explored by a hydroponic experiment. Results: D62B showed lower Cd translocated to shoot in comparison with Luhui17. The translocation factor (TF) of D62B varied from 0.11 to 0.15. Cd exposure promoted the synthesis of non-protein thiols in two rice lines, particularly in roots. Syntheses of glutathione (GSH) and phytochelatins (PCs) in root of D62B were greater than those of Luhui17. Cd concentration in xylem sap of D62B was significant positively correlated with the malic acid, citric acid and tartaric acid concentrations. The citric acid and tartaric acid concentrations in xylem sap of D62B were significantly lower than those of Luhui17. There was no significant difference for malic acid between two rice lines. Conclusions: More GSH and PCs in root of D62B was beneficial to Cd retention in root. Furthermore, the involvement of lower citric acid and tartaric acid in Cd translocated in xylem sap of D62B resulted in lower Cd accumulation in shoot. [ABSTRACT FROM AUTHOR]

Purpose: Blood velocity and flow rate information may be helpful for a wide variety of applications, but it often requires separate acquisitions. The dynamic information combined with the high spatial resolution of four‐dimensional computed tomography angiography (4D‐CTA) offers the possibility to quantify blood flow simultaneous to vascular anatomy. Methods: A 4D‐CTA clinical protocol with a novel dedicated postprocessing were validated in vitro in a patient‐specific model, and tested in a pilot study of six patients. Blood flow was assessed in both internal carotid (ICAs) and vertebral (VAs) arteries by analyzing spatial displacement of contrast agent in the form of time‐intensity curves (TICs). Unlike previous approaches, it does not require any a priori assumptions about TIC shape, but rather computes mean velocity and flow rates from the spatial displacement of the TICs along the automatically segmented vessels. Results: In vitro experiments showed good agreement between 4D‐CTA and flowmeter measurements under steady and pulsatile flow conditions. In vivo measurements exhibited large interpatient variability of the TIC shapes, from which blood flow rates could nevertheless be successfully measured in all patients and investigated vessels. On average, measured flow rates were 3.2 ± 0.7 ml/s (in ICAs) and 1.3 ± 0.8 ml/s (in VAs) consistent with previous reference standards. Contrary to our novel approach, which considered the full TIC shape, application of previous time‐to‐peak analyses based on idealized TIC shapes showed limited reliability. Conclusions: We demonstrate the high potential of 4D‐CTA for assessing blood velocity and flow rate in addition to anatomical evaluation. The wide variety of TIC shapes encountered in vivo highlights the importance of an adaptive TIC analysis as proposed in the present work. [ABSTRACT FROM AUTHOR]

Purpose: To obtain a fast and robust fat‐water separation with simultaneous estimation of water T1, fat T1, and fat fraction maps. Methods: We modified an MR fingerprinting (MRF) framework to use a single dictionary combination of a water and fat dictionary. A variable TE acquisition pattern with maximum TE = 4.8 ms was used to increase the fat–water separability. Radiofrequency (RF) spoiling was used to reduce the size of the dictionary by reducing T2 sensitivity. The technique was compared both in vitro and in vivo to an MRF method that incorporated 3‐point Dixon (DIXON MRF), as well as Cartesian IDEAL with different acquisition parameters. Results: The proposed dictionary‐based fat–water separation technique (DBFW MRF) successfully provided fat fraction, water, and fat T1, B0, and B1+ maps both in vitro and in vivo. The fat fraction and water T1 values obtained with DBFW MRF show excellent agreement with DIXON MRF as well as with the reference values obtained using a Cartesian IDEAL with a long TR (concordance correlation coefficient: 0.97/0.99 for fat fraction–water T1). Whereas fat fraction values with Cartesian IDEAL were degraded in the presence of T1 saturation, MRF methods successfully estimated and accounted for T1 in the fat fraction estimates. Conclusion: The DBFW MRF technique can successfully provide T1 and fat fraction quantification in under 20 s per slice, intrinsically correcting T1 biases typical of fast Dixon techniques. These features could improve the diagnostic quality and use of images in presence of fat. [ABSTRACT FROM AUTHOR]

Purpose: To optimize phase‐contrast (PC) MRI for the measurement of global cerebral blood flow (CBF) in the mouse at 11.7T. Methods: We determined proper velocity encoding (VENC) for internal carotid arteries (ICAs) and vertebral arteries (VAs). Next, we optimized spatial resolution of the sequence. To shorten scan time without compromising data quality, we further optimized repetition time and developed a reduced field‐of‐view (FOV) scheme for ICA and VA PC MRI. Whole‐brain volume was determined with T2‐weighted image to obtain unit‐volume CBF. Results: Peak flow velocities were 13.8 ± 1.7, 14.4 ± 0.6, 6.5 ± 1.7, and 6.7 ± 1.3 cm/s for left ICA, right ICA, left VA, and right VA, respectively. Thus, VENC values of 20 and 10 cm/s were chosen for ICA and VA PC MRI, respectively. An in‐plane spatial resolution of 50 × 50 μm2 was found to provide a reasonable trade‐off between reducing partial‐volume effects and maintaining signal‐to‐noise ratio. Because of the fact that saturated spins in the imaging slice are rapidly replaced by fresh spins, TR of the sequence can be decreased to as short as 15 ms without reducing signal intensity, thereby substantially lowering scan time. Moreover, reduced FOV along the phase‐encoding direction was able to shorten scan time by 33.3% while maintaining measurement accuracy. With these optimizations, it took 96 seconds to evaluate CBF with a test‐retest variability of approximately 5% and an inter‐rater correlation of >0.95. Global unit‐volume CBF was found to be 279.5 ± 11.1 mL of blood/100 ml of tissue/min. Conclusion: We have optimized PC MRI for noninvasive quantification of blood flow in mice at 11.7T. [ABSTRACT FROM AUTHOR]

Changes in vegetation type and climate associated with elevation can strongly affect the soil properties, but their effects on soil nutrient stoichiometry and enzymatic activities have rarely been studied. The contents of soil organic carbon (SOC), total nitrogen (TN), total phosphorus (TP), available nitrogen (AN), available phosphorus (AP) and available potassium (AK) and activities of six soil enzymes involved in C, N and P cycles were measured along an elevational gradient in the dry-hot valley region of China. C:P, N:P ratios first increased and then decreased with elevation, with the highest values of 89.57 and 4.07, respectively. AN:AP and AN:AK ratios increased linearly with elevation. Absolute enzymatic activities (i.e. per unit of oven-dried soil) tended to increase slightly with elevation, and specific enzymatic activities (i.e. per unit of SOC), except for phosphatase, first significantly decreased and then increased with elevation. A redundancy analysis showed that variations of soil nutrient content and stoichiometry were explained 76.1% by absolute and specific enzymatic activities. The elevational gradient was associated with a shift in nutrient limitation for ecosystem functions and processes, and the specific enzymatic activities responded more clearly than the absolute enzymatic activities to the elevational gradient in this dry-hot valley region. [ABSTRACT FROM AUTHOR]

DNA methylation is an important epigenetic modification that governs transcriptional regulation. The methylation mark is read by a special class of proteins called methyl-CpG-binding domain proteins. The role of DNA methylation has been found in X-chromosome inactivation, genomic imprinting, transposon silencing, and self-incompatibility. Recently, remodeling of global DNA methylation was demonstrated in Arabidopsis during low phosphate availability. The present study reports that AtMBD4 gene of Arabidopsis negatively regulates phosphate starvation. The T-DNA insertion mutation at the AtMBD4 locus exhibited altered root architecture as compared to wild-type plants. Using microarray hybridization and analysis, an increased transcript accumulation of 242 genes was observed in the mutant. Many of these genes were related to phosphate transporters and transcription factors, involved in phosphate starvation response. Comparison of data of atmbd4 mutant with publicly available microarray data of phosphate starvation response indicated the role of AtMBD4 protein in phosphate starvation response. Further, promoter analysis of up-regulated genes suggested that cis-regulatory elements like MBS, W-box, and B1BS are more prominent in the promoters of up-regulated genes. Upon performing a methylation-specific PCR, a decreased DNA methylation in the promoter regions of up-regulated genes was observed. The accumulation of anthocyanin and inorganic phosphate in the atmbd4 mutant was found to be higher than the wild-type plant. Altered root morphology, up-regulation of phosphate starvation-induced genes in atmbd4 mutant suggests that AtMBD4 negatively regulates the phosphate starvation response. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the ruminal parameters (pH, N-NH3, and microbial protein) and morphometry of the rumen and intestine of sheep fed with a diet containing four different levels of the spineless cactus variety, Baiana. The experiment was conducted at the National Semi-Arid Institute in Campina Grande, PB, Brazil. A total of 40 male sheep submitted to the confinement regime were used in a completely randomized design with four treatments (0, 15, 30, and 45% dry matter basis) and ten replicates, with an initial body weight of 23.7 ± 3.08 kg. Experimental diets were composed of ground corn, soybean meal, urea, mineral supplement, limestone, Tifton 85 hay, and spineless cactus of the Baiana variety. The pH, ammonia nitrogen, and microbial protein were evaluated in the ruminal fluid, alongside the morphometric characteristics of the rumen and intestine. While the addition of the spineless cactus did not affect N-NH3, it caused a linear reduction in the ruminal pH following 4 h of feeding, and also increased the microbial protein. In addition, it stimulated a reduction in the height of the papillae and the muscle layer of the rumen, and induced the mucosal height in the intestine to increase. The addition of up to 30% of spineless cactus in the diet of sheep without a defined breed did not alter the N-NH3, pH, and ruminal histology, but it did increase the production of microbial protein and intestinal mucosa. [ABSTRACT FROM AUTHOR]

Strigolactones (SLs) are carotenoid-derived phytohormones that are known to influence various aspects of plant growth and development. As root-derived signals, SLs can enhance symbiosis between plants and arbuscular mycorrhizal fungi (AMF). However, little is known about the roles of SLs in plant defense against soil-borne pathogens. Here, we determined that infection with root-knot nematodes (RKNs; Meloidogyne incognita) induced SL biosynthesis in roots of tomato (Solanum lycopersicum). Silencing of SL biosynthesis genes compromised plant defense against RKNs, whilst application of the SL analog rac GR24 enhanced it. Accumulation of endogenous jasmonic acid (JA) and abscisic acid (ABA) in the roots in response to RKN infection was enhanced by silencing of SL biosynthetic genes and was suppressed by application of rac GR24. Genetic evidence showed that JA was a positive regulator of defense against RKNs while ABA was a negative regulator. In addition, rac GR24 enhanced the defense against nematode in a JA-deficient mutant but not in an ABA-deficient mutant. Silencing of SL biosynthetic genes resulted in up-regulation of MYC2, which negatively regulated defense against RKNs. Our results demonstrate that SLs play a positive role in nematode defense in tomato and that MYC2 negatively regulates this defense, potentially by mediating hormone crosstalk among SLs, ABA and JA. [ABSTRACT FROM AUTHOR]

Background: Blood transfusions are administered to children and adults with sickle cell anemia (SCA) for secondary stroke prevention, or as treatment for recurrent pain crises or acute anemia, but transfusion effects on cerebral hemodynamics and metabolism are not well-characterized.Purpose: To compare blood transfusion-induced changes in hemometabolic parameters, including oxygen extraction fraction (OEF) and cerebral blood flow (CBF), within and between adults and children with SCA.Study Type: Prospective, longitudinal study.Subjects: Adults with SCA (n = 16) receiving simple (n = 7) or exchange (n = 9) transfusions and children with SCA (n = 11) receiving exchange transfusions were scanned once when hematocrit was near nadir and again within 7 days of transfusion. Adult controls without SCA or sickle trait (n = 7) were scanned twice on separate days.Field Strength/sequence: 3.0T T1 -weighted, T2 -weighted, and T2 -relaxation-under-spin-tagging (TRUST) imaging, and phase contrast angiography.Assessment: Global OEF was computed as the relative difference between venous oxygenation (from TRUST) and arterial oxygenation (from pulse oximetry). Global CBF was computed as total blood flow to the brain normalized by intracranial tissue volume.Statistical Tests: Hemometabolic variables were compared using two-sided Wilcoxon signed-rank tests; associations were analyzed using two-sided Spearman's correlation testing.Results: In adults with SCA, posttransfusion OEF = 0.38 ± 0.05 was lower (P = 0.001) than pretransfusion OEF = 0.45 ± 0.09. A change in OEF was correlated with increases in hematocrit (P = 0.02; rho = -0.62) and with pretransfusion hematocrit (P = 0.02; rho = 0.65). OEF changes after transfusion were greater (P = 0.002) in adults receiving simple versus exchange transfusions. Posttransfusion CBF = 77.7 ± 26.4 ml/100g/min was not different (P = 0.27) from pretransfusion CBF = 82.3 ± 30.2 ml/100g/min. In children with SCA, both posttransfusion OEF = 0.28 ± 0.04 and CBF = 76.4 ± 26.4 were lower than pretransfusion OEF = 0.36 ± 0.06 (P = 0.004) and CBF = 96.4 ± 16.5 (P = 0.004).Data Conclusion: Cerebral OEF reduces following transfusions in adults and children with SCA. CBF reduces following transfusions more often in children compared to adults, indicating that vascular reserve capacity may remain near exhaustion posttransfusion in many adults.Level Of Evidence: 2 Technical Efficacy Stage 5 J. Magn. Reson. Imaging 2019;49:466-477. [ABSTRACT FROM AUTHOR]

Conventional sensors for debris flow monitoring suffer from several drawbacks including low service life, low reliability in long-distance data transfer, and stability in severe weather conditions. Recently, fiber Bragg grating (FBG)-based sensors have been developed to monitor debris flows. However, they can be easily damaged by the impact forces of boulders within debris flow. This paper presents a new FBG-based device to measure the strain induced by the impact force of debris flow with high reliability and effectiveness. The effects of the impact forces of debris flows have been investigated. Then, the relationship between the strain and the debris flow energy correlating with the damage to building structures has been established. It is shown that this new FBG-based device is capable of monitoring and warning about debris flows. [ABSTRACT FROM AUTHOR]

Purpose: To develop a method for fast distortion‐ and blurring‐free imaging. Theory: EPI with point‐spread‐function (PSF) mapping can achieve distortion‐ and blurring‐free imaging at a cost of long acquisition time. In this study, an acquisition/reconstruction technique, termed "tilted‐CAIPI," is proposed to achieve >20× acceleration for PSF‐EPI. The proposed method systematically optimized the k‐space sampling trajectory with B0‐inhomogeneity‐informed reconstruction, to exploit the inherent signal correlation in PSF‐EPI and take full advantage of coil sensitivity. Susceptibility‐induced phase accumulation is regarded as an additional encoding that is estimated by calibration data and integrated into reconstruction. Self‐navigated phase correction was developed to correct shot‐to‐shot phase variation in diffusion imaging. Methods: Tilted‐CAIPI was implemented at 3T, with incorporation of partial Fourier and simultaneous multislice to achieve further accelerations. T2‐weighted, T2*‐weighted, and diffusion‐weighted imaging experiments were conducted to evaluate the proposed method. Results: The ability of tilted‐CAIPI to provide highly accelerated imaging without distortion and blurring was demonstrated through in vivo brain experiments, where only 8 shots per simultaneous slice group were required to provide high‐quality, high‐SNR imaging at 0.8–1 mm resolution. Conclusion: Tilted‐CAIPI achieved fast distortion‐ and blurring‐free imaging with high SNR. Whole‐brain T2‐weighted, T2*‐weighted, and diffusion imaging can be obtained in just 15–60 s. [ABSTRACT FROM AUTHOR]

The photoresponsive characteristics of SrTiO3-based oxide heterointerfaces at different thicknesses and strains are investigated. In addition to the typical persistent photoconductivity, the transient photoconductivity is observed at the heterointerfaces below the critical thickness. More intriguingly, it shows a transition from the transient photoconductivity to the persistent photoconductivity for the interfaces at the critical thickness with enhancing temperatures, which is related to the dominant role of thermal energy. Moreover, larger strain at the LaAlO3/SrTiO3 interfaces produces a roughly greater photoinduced change in the resistance than the strain-relaxed (La0.3Sr0.7)(Al0.65Ta0.35)O3/SrTiO3 interfaces. Our results provide deeper insight into the photoresponsive properties and intrinsic mechanisms of two-dimensional electron gas at complex oxide interfaces. [ABSTRACT FROM AUTHOR]

Bees receive nectar and pollen as reward for pollinating plants. Pollen of different plant species varies widely in nutritional composition. In order to select pollen of appropriate nutritional quality, bees would benefit if they could distinguish different pollen types. Whether they rely on visual, olfactory and/or chemotactile cues to distinguish between different pollen types, has however been little studied. In this study, we examined whether and how Apis mellifera workers differentiate between almond and apple pollen. We used differential proboscis extension response conditioning with olfactory and chemotactile stimulation, in light and darkness, and in summer and winter bees. We found that honeybees were only able to differentiate between different pollen types, when they could use both chemotactile and olfactory cues. Visual cues further improved learning performance. Summer bees learned faster than winter bees. Our results thus highlight the importance of multisensory information for pollen discrimination. [ABSTRACT FROM AUTHOR]

Background: Whole-brain global cerebral blood flow (CBF) determined by MRI techniques, calculated using total CBF (TCBF) from phase-contrast MRI (PC-MRI), and brain parenchyma volume (BPV) from T1 -weighted image, have become increasingly popular in many applications.Purpose/hypothesis: To determine if MRI-based measurements of whole-brain global CBF data obtained across different field strengths could be merged, TCBF and BPV data acquired at 1.5T and 3T were compared.Study Type: Prospective study.Population: Seventeen healthy subjects (eight females, aged 21-29 years old).Field Strength/sequence: Fast spoiled gradient echo (FSPGR) and PC-MRI at both 1.5T and 3T.Assessment: TCBF and BPV data acquired at 1.5T and 3T were compared.Statistical Tests: The relationships of TCBF and whole-brain global CBF between two field strengths were examined by using the Pearson correlation coefficient analysis and intraclass correlation coefficient (ICC).Results: Regression analysis revealed a strong correlation between TCBF at two field strengths (R2  = 0.78, P < 0.001), and the ICC was 0.85, suggesting measurements of TCBF at 1.5T were comparable and correlated with those at 3T. There was a significant difference in BPV between field strengths, where the white matter estimate was significantly larger at 1.5T when compared with that at 3T (P < 0.001). When TCBF was further normalized to the brain parenchyma mass to obtain whole-brain global CBF, it only showed a moderate correlation between measurements at the two field strengths (R2  = 0.46, P = 0.003) and lower ICC of 0.66, reflecting the slightly higher interstrength variability in the whole-brain global CBF measurements.Data Conclusion: TCBF measurements could be performed equally well with comparable results at both field strengths, but specific attention should be given when TCBF is further normalized to BPV to obtain whole-brain global CBF.Level Of Evidence: 1 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018;47:1273-1280. [ABSTRACT FROM AUTHOR]

Background: Bypass surgery for complex intracranial aneurysms (IAs) results in drastic blood flow changes in intracranial arteries. The aim of the study was to elucidate how vessels adapt to blood flow changes after bypass surgery with phase-contrast magnetic resonance imaging (PC-MRI).Methods: This is a prospective observational study to assess changes of the blood flow in intracranial arteries after bypass surgery for IAs. Flow rates and vessel diameters were measured with PC-MRI in 52 intracranial arteries of 7 healthy volunteers and 31 arteries of 8 IA patients who underwent bypass surgery. Wall shear stress (WSS) was calculated with the Hagen-Poiseuille formula. In 18 arteries of 5 patients, the same measurement was performed 1, 3, and 12 months after surgery.Results: PC-MRI showed a strong positive correlation between the flow rate and the third power of vessel diameter in both healthy volunteers (r = 0.82, P < 0.0001) and IA patients (r = 0.90, P < 0.0001), indicating the constant WSS. Of the 18 arteries in 5 patients, WSS increased in 7 arteries and decreased in 11 arteries immediately after surgery. In the WSS-increased group, WSS returned to the preoperative value in the third postoperative month. In the WSS-decreased group, WSS increased in the 12th month, but did not return to the preoperative level.Conclusions: In a physiological state, WSS was constant in intracranial arteries. Changed WSS after bypass surgery tended to return to the preoperative value, suggesting that vessel diameter and flow rate might be controlled so that WSS remains constant. [ABSTRACT FROM AUTHOR]

Individuals with anxiety/depression often have exaggerated cardiovascular responses to stressful stimuli and a comorbidity with hypertension. Alternatively, individuals with hypertension can be more anxious. In the present study cardiovascular changes were evaluated during behavioral testing of anxious behavior on the elevated plus maze (EPM) in the spontaneously hypertensive rat (SHR), a rodent model of neurogenic hypertension, and compared to the response of the more anxious, but normotensive, Wistar-Kyoto rat (WKY). Manganese-enhanced magnetic resonance imaging (MEMRI) was used to identify regional differences in baseline brain activity. Parallel to indicators of elevated behavioral anxiety on the EPM, WKYs had a greater increase in blood pressure but not heart rate when compared to the SHR while on the EPM. Associated with differences in anxiety-related behavior and autonomic responses, we observed increased baseline activity in the amygdala, central gray, habenula and interpeduncular nucleus with MEMRI of the WKY compared to the SHR. Conversely, elevated baseline brain activity was found in regions associated with blood pressure control and system arousal, including the hypothalamus, locus coeruleus and pedunculopontine tegmental nucleus, in the SHR vs WKY, in-line with increased resting blood pressure and increased mobility in this strain. Lastly, reduced activity in hippocampal regions was identified in the SHR compared to the WKY and may be associated with cognitive impairment previously reported in the SHR. Thus, autonomic reactivity may be a true measure of stress in rodent models of anxiety and MEMRI presents a powerful technique to uncover novel brain mechanisms of blood pressure control. [ABSTRACT FROM AUTHOR]

Groundnut seeds were used to get a milk-like product and to create yoghurt. The produced milk-like products and yoghurts were subjected to some physicochemical and sensorial analysis by using control cow milk and yoghurt. The groundnut milk and its yoghurt had higher total solids, fat, protein and carbohydrates, water holding capacities comparing than cow milk and yoghurt. Groundnut milk contained higher total solids (15.923 g/100 g), fat (5.74 g/100 g) and its yoghurt contained 18.153 g/100 g total solids and 5.430 g/100 g fat. These products also had a higher calorific value, 417 kJ/100 g and 379.5 kJ/100 g respectively. The apparent viscosity of groundnut milk was higher than cow milk at all shear rates and there was a close relationship between viscosity and shear rates. The water holding capacity of groundnut milk yoghurt was 65.68 g/100 g and significantly higher than cow milk yoghurt sample (44.27 g/100 g). The syneresis of groundnut milk yoghurt was 27.40 ml/100 ml and significantly lower than cow milk yoghurt (37.63 ml/100 ml). Both the groundnut milk and yoghurt contained higher amount of unsaturated fatty acids and amino acids compared to cow milk and its yoghurt. [ABSTRACT FROM AUTHOR]

Purpose: Simultaneous multi‐slice (SMS) imaging is an advantageous method for accelerating MRI scans, allowing reduced scan time, increased slice coverage, or high temporal resolution with limited image quality penalties. In this work we combine the advantages of SMS acceleration with the motion correction and artifact reduction capabilities of the PROPELLER technique. Methods: A PROPELLER sequence was developed with support for CAIPIRINHA and phase optimized multiband radio frequency pulses. To minimize the time spent on acquiring calibration data, both in‐plane‐generalized autocalibrating partial parallel acquisition (GRAPPA) and slice‐GRAPPA weights for all PROPELLER blade angles were calibrated on a single fully sampled PROPELLER blade volume. Therefore, the proposed acquisition included a single fully sampled blade volume, with the remaining blades accelerated in both the phase and slice encoding directions without additional auto calibrating signal lines. Comparison to 3D RARE was performed as well as demonstration of 3D motion correction performance on the SMS PROPELLER data. Results: We show that PROPELLER acquisitions can be efficiently accelerated with SMS using a short embedded calibration. The potential in combining these two techniques was demonstrated with a high quality 1.0 × 1.0 × 1.0 mm3 resolution T2‐weighted volume, free from banding artifacts, and capable of 3D retrospective motion correction, with higher effective resolution compared to 3D RARE. Conclusion: With the combination of SMS acceleration and PROPELLER imaging, thin‐sliced reformattable T2‐weighted image volumes with 3D retrospective motion correction capabilities can be rapidly acquired with low sensitivity to flow and head motion. Magn Reson Med 80:496–506, 2018. © 2017 International Society for Magnetic Resonance in Medicine. [ABSTRACT FROM AUTHOR]

Retrograde pathways occurring between chloroplasts, mitochondria, and the nucleus involve oxidative and antioxidative signals that, working in a synergistic or antagonistic mode, control the expression of specific patterns of genes following stress perception. Increasing evidence also underlines the relevance of mitochondrion-chloroplast-nucleus crosstalk in modulating the whole cellular redox metabolism by a controlled and integrated flux of information. Plants can maintain the acquired tolerance by a stress memory, also operating at the transgenerational level, via epigenetic and miRNA-based mechanisms controlling gene expression. Data discussed in this review strengthen the idea that ROS, redox signals, and shifts in cellular redox balance permeate the signalling network leading to cross-tolerance. The identification of specific ROS/antioxidative signatures leading a plant to different fates under stress is pivotal for identifying strategies to monitor and increase plant fitness in a changing environment. This review provides an update of the plant redox signalling network implicated in stress responses, in particular in cross-tolerance acquisition. The interplay between reactive oxygen species (ROS), ROS-derived signals, and antioxidative pathways is also discussed in terms of plant acclimation to stress in the short and long term. [ABSTRACT FROM AUTHOR]

This study investigated the effects of partially replacing barley grains with sugar beet pulp (SBP), with and without roasted canola seed (RCS) on ruminal pH, ruminal volatile fatty acid (VFA) concentrations, ruminal histomorphometric characteristics, and performance in finishing lambs fed a high concentrate diet. Twenty-four Arabian male lambs (23.7 ± 2.5 kg bodyweight, 118 ± 10 days in age) were used for 99 days in a completely randomised design with a 2 · 2 factorial arrangement. Lambs were fed with a high concentrate diet containing (1) 68% barley (B) (2) barley plus 7% RCS (B + RCS) (3) 36% SBP, (4) SBP plus 7% RCS (SBP + RCS). Ruminal fluid pH and VFAconcentrations were determined at 0, 2, 4 and 8 h post-feeding 1 day before slaughter day. Tissue samples were collected for histomorphometric study at slaughter day. Average daily gain of the lambs was not affected by partial replacement of barley with SBP, however it was improved by RCS inclusion (P < 0.05). Diets with RCS had significantly lower (P < 0.05) neutral detergent fibre and acid detergent fibre digestibility values than diets without RCS (P < 0.05). Both SBP and RCS increased ruminal pH, molar proportions of acetate, isobutyrate but decreased molar proportion of propionate in rumen content (P < 0.05). The height, width, epithelial thickness and tunica muscularis of rumen papilla and reticulum folds were increased by SBP (P < 0.05). Density of reticulum folds were higher in lambs fed by higher SBP (P < 0.05). Inclusion of RCS significantly increased papillae height and thickness of epithelium (P < 0.05). In conclusion, partially replacing barley with SBP as well as RCS inclusion prevented a drop in the ruminal pH, and improved the morphology of the rumen-reticulum in finishing lambs fed a high concentrate diet. [ABSTRACT FROM AUTHOR]

Purpose: Three‐dimensional (3D) multiplexed sensitivity encoding and reconstruction (3D‐MUSER) algorithm is proposed to reduce aliasing artifacts and signal corruption caused by inter‐shot 3D phase variations in 3D diffusion‐weighted echo planar imaging (DW‐EPI). Theory and Methods: 3D‐MUSER extends the original framework of multiplexed sensitivity encoding (MUSE) to a hybrid k‐space‐based reconstruction, thereby enabling the correction of inter‐shot 3D phase variations. A 3D single‐shot EPI navigator echo was used to measure inter‐shot 3D phase variations. The performance of 3D‐MUSER was evaluated by analyses of point‐spread function (PSF), signal‐to‐noise ratio (SNR), and artifact levels. The efficacy of phase correction using 3D‐MUSER for different slab thicknesses and b‐values were investigated. Results: Simulations showed that 3D‐MUSER could eliminate artifacts because of through‐slab phase variation and reduce noise amplification because of SENSE reconstruction. All aliasing artifacts and signal corruption in 3D interleaved DW‐EPI acquired with different slab thicknesses and b‐values were reduced by our new algorithm. A near‐whole brain single‐slab 3D DTI with 1.3‐mm isotropic voxel acquired at 1.5T was successfully demonstrated. Conclusion: 3D phase correction for 3D interleaved DW‐EPI data is made possible by 3D‐MUSER, thereby improving feasible slab thickness and maximum feasible b‐value. Magn Reson Med 79:2702–2712, 2018. © 2017 International Society for Magnetic Resonance in Medicine. [ABSTRACT FROM AUTHOR]

Purpose: This study demonstrates a novel PROPELLER (periodically rotated overlapping parallel lines with enhanced reconstruction) pulse sequence, termed Steer‐PROP, based on gradient and spin echo (GRASE), to reduce the imaging times and address phase errors inherent to GRASE. The study also illustrates the feasibility of using Steer‐PROP as an alternative to single‐shot echo planar imaging (SS‐EPI) to produce distortion‐free diffusion images in all imaging planes. Methods: Steer‐PROP uses a series of blip gradient pulses to produce N (N = 3‐5) adjacent k‐space blades in each repetition time, where N is the number of gradient echoes in a GRASE sequence. This sampling strategy enables a phase correction algorithm to systematically address the GRASE phase errors as well as the motion‐induced phase inconsistency. Steer‐PROP was evaluated on phantoms and healthy human subjects at both 1.5T and 3.0T for T2‐ and diffusion‐weighted imaging. Results: Steer‐PROP produced similar image quality as conventional PROPELLER based on fast spin echo (FSE), while taking only a fraction (e.g., 1/3) of the scan time. The robustness against motion in Steer‐PROP was comparable to that of FSE‐based PROPELLER. Using Steer‐PROP, high quality and distortion‐free diffusion images were obtained from human subjects in all imaging planes, demonstrating a considerable advantage over SS‐EPI. Conclusion: The proposed Steer‐PROP sequence can substantially reduce the scan times compared with FSE‐based PROPELLER while achieving adequate image quality. The novel k‐space sampling strategy in Steer‐PROP not only enables an integrated phase correction method that addresses various sources of phase errors, but also minimizes the echo spacing compared with alternative sampling strategies. Steer‐PROP can also be a viable alternative to SS‐EPI to decrease image distortion in all imaging planes. Magn Reson Med 79:2533–2541, 2018. © 2017 International Society for Magnetic Resonance in Medicine. [ABSTRACT FROM AUTHOR]