Plants often face a variety of abiotic stresses, which affects them negatively and lead to yield loss. The antioxidant system efficiently removes excessive reactive oxygen species and maintains redox ...homeostasis in plants. With better understanding of these protective mechanisms, recently the concept of hydrogen sulfide (H2S) and its role in cell signaling has become the center of attention. H2S has been recognized as a third gasotransmitter and a potent regulator of growth and development processes such as germination, maturation, senescence and defense mechanism in plants. Because of its gaseous nature, H2S can diffuse to different part of the cells and balance the antioxidant pools by supplying sulfur to cells. H2S showed tolerance against a plethora of adverse environmental conditions like drought, salt, high temperature, cold, heavy metals and flood via changing in level of osmolytes, malonaldialdehyde, Na+/K+ uptake, activities of H2S biosynthesis and antioxidative enzymes. It also promotes cross adaptation through persulfidation. H2S along with calcium, methylglyoxal and nitric oxide, and their cross talk induces the expression of mitogen activated protein kinases as well as other genes in response to stress. Therefore, it is sensible to evaluate and explore the stress responsive genes involved in H2S regulated homeostasis and stress tolerance. The current article is aimed to summarize the recent updates on H2S‐mediated gene regulation in special reference to abiotic stress tolerance mechanism, and cross adaptation in plants. Moreover, new insights into the H2S‐associated signal transduction pathway have also been explored.
Micro-electro-mechanical system (MEMS) technology has radically changed the scale, performance, and cost of a wide variety of sensors and actuators by taking advantage of batch fabrication. The ...multidisciplinary nature of MEMS employs knowledge of diverse technical areas to realize improved and novel transducer systems. This also brings various associated challenges that are otherwise being ignored in a simple macro-dimensional system. MEMS devices typically comprise several deposited thick and thin films as well as bonded of dissimilar materials (like silicon, metal, glass, etc.). Residual stress is one of the most common outcomes during this integration/stacking of distinctly different materials for the fabrication of novel MEMS structures. The residual stress may significantly affect the performance and reliability of the fabricated devices. Thus, the evaluation and regulation of residual stress are one of the crucial aspects to assess the functioning of modern-day MEMS devices. This paper reviewed the origins of residual stress in MEMS fabrication processes. Different techniques involved in testing and characterization of the residual stresses are reviewed. Few important case studies are discussed to highlight the effect of residual stress (generated during various fabrication processes) on characteristics of different MEMS structures. The brief overview of the possible route to minimize the residual stresses is also presented.
X-ray diffraction (XRD) techniques are powerful, non-destructive characterization tool with minimal sample preparation. XRD provides the first information about the materials phases, crystalline ...structure, average crystallite size, micro and macro strain, orientation parameter, texture coefficient, degree of crystallinity, crystal defects etc. XRD analysis provides information about the bulk, polycrystalline thin films, and multilayer structures, which is very important in various scientific and material engineering fields. This review discusses the diffraction related phenomena/principles such as powder X-ray diffraction, and thin-film/grazing incidence X-ray diffraction (GIXRD) comprehensively for thin film samples which are used frequently in various branches of science and technology. The review also covers few case studies on polycrystalline thin-film samples related to phase analysis, preferred orientation parameter (texture coefficient) analysis, stress evaluation in thin films and multilayer, multiphase content identification, bifurcation of multiphase on multilayer samples, depth profiling in thin-film/ multilayer structures, the impact of doping effect on structural properties of thin films etc., comprehensively using GIXRD/XRD.
Here, we demonstrates the fabrication of binder free and very efficient supercapacitor electrode based on tungsten nitride (W2N) thin film on stainless steel (SS) substrate using reactive sputtering ...technique. W2N thin film as a working electrode exhibits high specific capacitance (163 F g−1 at 0.5 mA cm−2 in 1 M H2SO4) along with excellent cycling stability. The binder free symmetric supercapacitor (W2N||W2N) device delivers a high specific capacitance (80 Fg-1) and long life span (90.46% capacitance retention after 10,000 cycles) along with high energy (12.92 Whkg−1) and power (∼674 kWkg−1 at 9.36 Whkg−1) densities. These observed excellent electrochemical performances of the present W2N thin film based supercapacitor device, recommend it as a potential candidate for energy storage applications.
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•W2N thin film is deposited on stainless steel substrate using reactive sputtering.•A binder free symmetric device based on W2N/SS configuration is constructed.•W2N||W2N device exhibits high energy density and outstanding cycling stability.•The W2N||W2N supercapacitor device shows a long retention for 10,000 cycles.
Sleep is an essential process that supports learning and memory by acting on synapses through poorly understood molecular mechanisms. Using biochemistry, proteomics, and imaging in mice, we find that ...during sleep, synapses undergo widespread alterations in composition and signaling, including weakening of synapses through removal and dephosphorylation of synaptic AMPA-type glutamate receptors. These changes are driven by the immediate early gene Homer1a and signaling from group I metabotropic glutamate receptors mGluR1/5. Homer1a serves as a molecular integrator of arousal and sleep need via the wake- and sleep-promoting neuromodulators, noradrenaline and adenosine, respectively. Our data suggest that homeostatic scaling-down, a global form of synaptic plasticity, is active during sleep to remodel synapses and participates in the consolidation of contextual memory.
We assembled the sequences from deep RNA sequencing experiments by the Genotype-Tissue Expression (GTEx) project, to create a new catalog of human genes and transcripts, called CHESS. The new ...database contains 42,611 genes, of which 20,352 are potentially protein-coding and 22,259 are noncoding, and a total of 323,258 transcripts. These include 224 novel protein-coding genes and 116,156 novel transcripts. We detected over 30 million additional transcripts at more than 650,000 genomic loci, nearly all of which are likely nonfunctional, revealing a heretofore unappreciated amount of transcriptional noise in human cells. The CHESS database is available at http://ccb.jhu.edu/chess .
Hypoxia-inducible factor 1 (HIF-1) activates transcription of genes encoding proteins that play key roles in breast cancer biology. We hypothesized that interaction of HIF-1 with epigenetic ...regulators may increase HIF-1 transcriptional activity, and thereby promote breast cancer progression. We report that the histone demethylase jumonji domain containing protein 2C (JMJD2C) selectively interacts with HIF-1α, but not HIF-2α, and that HIF-1α mediates recruitment of JMJD2C to the hypoxia response elements of HIF-1 target genes. JMJD2C decreases trimethylation of histone H3 at lysine 9, and enhances HIF-1 binding to hypoxia response elements, thereby activating transcription of BNIP3 , LDHA , PDK1 , and SLC2A1 , which encode proteins that are required for metabolic reprogramming, as well as LOXL2 and L1CAM , which encode proteins that are required for lung metastasis. JMJD2C expression is significantly associated with expression of GLUT1, LDHA, PDK1, LOX, LOXL2, and L1CAM mRNA in human breast cancer biopsies. JMJD2C knockdown inhibits breast tumor growth and spontaneous metastasis to the lungs of mice following mammary fat pad injection. Taken together, these findings establish an important epigenetic mechanism that stimulates HIF-1–mediated transactivation of genes encoding proteins involved in metabolic reprogramming and lung metastasis in breast cancer.
Epithelial-mesenchymal transition (EMT) is a dynamic process by which the cells transdifferentiate into two or more somatic states. The metastatic spread begins with tumor cells disseminated from the ...primary tumor via intravasation, hematogenous transit and extravasation to reach the distant organs to form micro- or macrometastasis. Dissemination of tumor cells or metastasis is a crucial stage in cancer progression and accounts for majority of cancer associated morbidity and mortality. Advances in technology has now enabled detection and capture of tumor cells that escape from primary site into the bloodstream. Such tumor cells which are found in transit in the blood are referred to as circulating tumor cells (CTCs) and they represent the early step in metastatic cascade. The dynamic changes in EMT phenotype in CTCs plays a key role in cancer metastasis. This review will focus on the role of EMT in cancer progression, circulating tumor cells and its clinical relevance.
In this article, Polarized Raman spectroscopy is being used to determine and validate the crystallographic orientations of Zinc blend crystals. Two crystals of GaAs and ZnTe oriented along (112) are ...used for Polarized Raman spectroscopic study. To realize the different angles (α) of the in-plane rotation along the surface normal, and the excitation laser polarization is fixed vertically and the sample is rotated. At the scattering side another polarizer is used to get different angles (β) of polarization. Raman spectroscopic technique has been used to study crystallographic plane identification by measuring the Raman scattered intensity using the variation in α and β angles of GaAs crystals while fixing the reference point in the crystal. GaAs crystal showed a different intensity pattern which is fitted by transformation matrix relation to identify the crystallographic plane direction. In ZnTe crystal due to resonance Raman scattering at room temperature and multi-phonon feature with green laser excitation 1LO phonon intensity does not show any variation by varying (α) rotation while rotating the angle at scattering side polarizer (β), LO intensity variation follows the cosine square law. In Resonant and Non-resonant Raman scattering by varying the temperature and laser excitation, the results of ZnTe are found to be different as compared to GaAs. As a result, Polarized Raman spectroscopic study can be done only in non-resonant Raman scattering perhaps using below-band gap excitation to avoid LO multi-phonon scattering.
The ubiquitin-like protein ubiquilin 2 (UBQLN2) has been genetically and pathologically linked to the neurodegenerative diseases amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), ...but its normal cellular functions are not well understood. In a search for UBQLN2-interacting proteins, we found an enrichment of stress granule (SG) components, including ALS/FTD-linked heterogeneous ribonucleoprotein fused in sarcoma (FUS). Through the use of an optimized SG detection method, we observed UBQLN2 and its interactors at SGs. A low complexity, Sti1-like repeat region in UBQLN2 was sufficient for its localization to SGs. Functionally, UBQLN2 negatively regulated SG formation. UBQLN2 increased the dynamics of FUS–RNA interaction and promoted the fluidity of FUS–RNA complexes at a single-molecule level. This solubilizing effect corresponded to a dispersal of FUS liquid droplets in vitro and a suppression of FUS SG formation in cells. ALS-linked mutations in UBQLN2 reduced its association with FUS and impaired its function in regulating FUS–RNA complex dynamics and SG formation. These results reveal a previously unrecognized role for UBQLN2 in regulating the early stages of liquid–liquid phase separation by directly modulating the fluidity of protein–RNA complexes and the dynamics of SG formation.
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