Improving drought and salinity tolerance in barley by application of salicylic acid and potassium nitrate

AbstractGrowth and physiological activities of barley (Hordeum vulgare L. cv. Gustoe) grown in soil cultures were evaluated to recognize the ameliorative role of salicylic acid (SA) and KNO3 against the negative effects of salt and water deficit stresses. Barley plants were subjected to three levels of NaCl (50, 100 and 150mM), three levels of water stress (80%, 70% and 50% of the soil water content (SWC) and the combination of 150mM NaCl+50μM SA, 150mM NaCl+10mM KNO3, 50% SWC+50μM SA and 50% SWC+10mM KNO3 for two weeks. Salt and water deficit stresses reduced the shoot growth, leaf photosynthetic pigments, K+ contents and provoked oxidative stress in leaves confirmed by considerable changes in soluble carbohydrate, proline, malondialdehyde (MDA), total phenolic compounds, antioxidant activity and Na+ contents. Leaf soluble protein of salt and water deficit treated plants was unaffected. The Na+/K+ ratio increased with increasing salt and water deficit treated plants. Application of 50μM SA or 10mM KNO3 to150mM NaCl and/or 50% SWC treated plants improved these attributes under salt and water stresses. Soluble carbohydrates in stressed plants may have a significant role in osmotic adjustment. It can be concluded that the addition of SA or KNO3 can ameliorate the oxidative stress in barley stressed plants. This ameliorative effect might be maintained through low MDA contents and decreased Na+/K+ ratio in leaves. This study also provided evidence for the ability of barley cultivation in salt and water deficit soils due to its capacity for osmotic adjustment

Plasmonic modulator based on gain-assisted metal-semiconductor-metal waveguide

We investigate plasmonic modulators with a gain material to be implemented as ultra-compact and ultra-fast active nanodevices in photonic integrated circuits. We analyze metal-semiconductor-metal (MSM) waveguides with InGaAsP-based active material layers as ultra-compact plasmonic modulators. The modulation is achieved by changing the gain of the core that results in different transmittance through the waveguides. A MSM waveguide enables high field localization and therefore high modulation speed. Bulk semiconductor, quantum wells and quantum dots, arranged in either horizontal or vertical layout, are considered as the core of the MSM waveguide. Dependences on the waveguide core size and gain values of various active materials are studied. The designs consider also practical aspects like n- and p-doped layers and barriers in order to obtain results as close to reality. The effective propagation constants in the MSM waveguides are calculated numerically. Their changes in the switching process are considered as a figure of merit. We show that a MSM waveguide with electrical current control of the gain incorporates compactness and deep modulation along with a reasonable level of transmittance

Temperature dependent piezoelectric response and strain–electric-field hysteresis of rare-earth modified bismuth ferrite ceramics

The rare-earth (RE)-modified bismuth ferrite (BiFeO3 or BFO) family of ferroelectrics have uncomplicated lead-free chemistries and simple perovskite structures. Due to the high Curie transition temperature of the parent BiFeO3 perovskite (∼830 °C), they are promising piezoelectric materials for use at elevated temperatures. However, the influence of the specific RE species on the electromechanical behavior at high temperatures and above the coercive electric-field is not widely reported. Here, structural analysis over multiple length scales using X-ray diffraction, transmission electron microscopy and piezoresponse force microscopy is coupled with a high electric-field cycling study and in situ converse d33 measurements up to 325 °C for three RE–BFO ceramic compositions, Bi0.86Sm0.14FeO3, Bi0.88Gd0.12FeO3 and Bi0.91Dy0.09FeO3. The ceramics exhibit different phase assemblages with varying amounts of polar rhombohedral R3c and intermediate antipolar orthorhombic Pbam phases as a function of the RE species. During electric-field cycling at electric-fields with amplitudes of 160 kV cm−1, peak-to-peak strains of 0.23–0.27% are reached for all three compositions. However, there are qualitative differences in the field-induced strain and electric current behavior as a function of electric-field cycling and the materials exhibit an electrical-history dependent behavior. Bi0.91Dy0.09FeO3 possesses an improved d33 stability as a function of temperature relative to the parent BFO perovskite and the highest depolarization temperature among the three RE–BFO compositions, with a stable d33 of ∼22 pC N−1 up to 325 °C

Nidogen-1 Contributes to the Interaction Network Involved in Pro-B Cell Retention in the Peri-sinusoidal Hematopoietic Stem Cell Niche

In the bone marrow, CXCL12 and IL-7 are essential for B cell differentiation, whereas hematopoietic stem cell (HSC) maintenance requires SCF and CXCL12. Peri-sinusoidal stromal (PSS) cells are the main source of IL-7, but their characterization as a pro-B cell niche remains limited. Here, we characterize pro-B cell supporting stromal cells and decipher the interaction network allowing pro-B cell retention. Preferential contacts are found between pro-B cells and PSS cells, which homogeneously express HSC and B cell niche genes. Furthermore, pro-B cells are frequently located in the vicinity of HSCs in the same niche. Using an interactome bioinformatics pipeline, we identify Nidogen-1 as essential for pro-B cell retention in the peri-sinusoidal niche as confirmed in Nidogen-1−/− mice. Finally, human pro-B cells and hematopoietic progenitors are observed close to similar IL-7+ stromal cells. Thus, a multispecific niche exists in mouse and human supporting both early progenitors and committed hematopoietic lineages

Somatic cell type specific gene transfer reveals a tumor-promoting function for p21Waf1/Cip1

How proteins participate in tumorigenesis can be obscured by their multifunctional nature. For example, depending on the cellular context, the cdk inhibitors can affect cell proliferation, cell motility, apoptosis, receptor tyrosine kinase signaling, and transcription. Thus, to determine how a protein contributes to tumorigenesis, we need to evaluate which functions are required in the developing tumor. Here we demonstrate that the RCAS/TvA system, originally developed to introduce oncogenes into somatic cells of mice, can be adapted to allow us to define the contribution that different functional domains make to tumor development. Studying the development of growth-factor-induced oligodendroglioma, we identified a critical role for the Cy elements in p21, and we showed that cyclin D1T286A, which accumulates in the nucleus of p21-deficient cells and binds to cdk4, could bypass the requirement for p21 during tumor development. These genetic results suggest that p21 acts through the cyclin D1–cdk4 complex to support tumor growth, and establish the utility of using a somatic cell modeling system for defining the contribution proteins make to tumor development

Barrier Tissue Macrophages: Functional Adaptation to Environmental Challenges

Macrophages are found throughout the body, where they have crucial roles in tissue development, homeostasis and remodeling, as well as being sentinels of the innate immune system that can contribute to protective immunity and inflammation. Barrier tissues, such as the intestine, lung, skin and liver, are exposed constantly to the outside world, which places special demands on resident cell populations such as macrophages. Here we review the mounting evidence that although macrophages in different barrier tissues may be derived from distinct progenitors, their highly specific properties are shaped by the local environment, which allows them to adapt precisely to the needs of their anatomical niche. We discuss the properties of macrophages in steady-state barrier tissues, outline the factors that shape their differentiation and behavior and describe how macrophages change during protective immunity and inflammation

Post-intervention Status in Patients With Refractory Myasthenia Gravis Treated With Eculizumab During REGAIN and Its Open-Label Extension

OBJECTIVE: To evaluate whether eculizumab helps patients with anti-acetylcholine receptor-positive (AChR+) refractory generalized myasthenia gravis (gMG) achieve the Myasthenia Gravis Foundation of America (MGFA) post-intervention status of minimal manifestations (MM), we assessed patients' status throughout REGAIN (Safety and Efficacy of Eculizumab in AChR+ Refractory Generalized Myasthenia Gravis) and its open-label extension. METHODS: Patients who completed the REGAIN randomized controlled trial and continued into the open-label extension were included in this tertiary endpoint analysis. Patients were assessed for the MGFA post-intervention status of improved, unchanged, worse, MM, and pharmacologic remission at defined time points during REGAIN and through week 130 of the open-label study. RESULTS: A total of 117 patients completed REGAIN and continued into the open-label study (eculizumab/eculizumab: 56; placebo/eculizumab: 61). At week 26 of REGAIN, more eculizumab-treated patients than placebo-treated patients achieved a status of improved (60.7% vs 41.7%) or MM (25.0% vs 13.3%; common OR: 2.3; 95% CI: 1.1-4.5). After 130 weeks of eculizumab treatment, 88.0% of patients achieved improved status and 57.3% of patients achieved MM status. The safety profile of eculizumab was consistent with its known profile and no new safety signals were detected. CONCLUSION: Eculizumab led to rapid and sustained achievement of MM in patients with AChR+ refractory gMG. These findings support the use of eculizumab in this previously difficult-to-treat patient population. CLINICALTRIALSGOV IDENTIFIER: REGAIN, NCT01997229; REGAIN open-label extension, NCT02301624. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that, after 26 weeks of eculizumab treatment, 25.0% of adults with AChR+ refractory gMG achieved MM, compared with 13.3% who received placebo

Minimal Symptom Expression' in Patients With Acetylcholine Receptor Antibody-Positive Refractory Generalized Myasthenia Gravis Treated With Eculizumab

The efficacy and tolerability of eculizumab were assessed in REGAIN, a 26-week, phase 3, randomized, double-blind, placebo-controlled study in anti-acetylcholine receptor antibody-positive (AChR+) refractory generalized myasthenia gravis (gMG), and its open-label extension