225 research outputs found
A Short Review on the Development of Salt Tolerant Cultivars in Rice
Rice is staple food for half of the world. With a population of almost 9.6 billion by the year 2050, there is a dire need of developing techniques to improve the crop plants, not only in terms of better yield but also to withstand harsh environmental conditions and stresses like drought, temperature, flood and salinity. Salinity is second to drought stress and hence it is very important to develop crops tolerant to salinity stress. This review discusses the mechanisms of salt tolerance and the recent developments in understanding the complex tolerance phenomena. One way to address the salinity issue is to develop tolerant rice varieties using conventional and modern breeding techniques for which screening the rice germplasm for the varieties with desired traits is critical. Conventional methods to develop tolerant rice varieties are discussed along with modern biotechnology techniques are also discussed. Quantitative Trait Loci (QTL) and Marker Assisted Selection (MAS) are promising techniques. In addition to these modern techniques, some recent developments in the fields of transgenic plants, haploid breeding and Somaclonal variations have also been discussed. The limited knowledge about molecular and genetic mechanisms to tolerate abiotic stresses, however is a barrier to efficiently develop tolerant cultivars. A combination of conventional and modern biotechnology techniques could possibly open up the new ways
Temperature Effects on the Kinetics of Ferrocene and Cobaltocenium in Methyltriphenylphosphonium Bromide Based Deep Eutectic Solvents
The oxidation of ferrocene (Fc/Fc+) and reduction of cobaltocenium (Cc+/Cc) under different temperatures has been studied by cyclic voltammetry and double potential step chronoamperometry in deep eutectic solvents (DESs) consisting of methyltriphenylphosphonium bromide salt with tri-ethylene glycol, glycerol or ethylene glycol as hydrogen bond donors. The temperature dependence of the measured physical properties of DESs (such as viscosity and conductivity) is discussed in detail. The kinetics of the redox couples are studied using cyclic voltammetry, and the standard heterogeneous electron transfer rate constant, k0 is found to be of the order of 10−5 to 10−4 cms−1 at different temperatures. The diffusion coefficient, D, of Fc and Cc+ is determined to lie between 8.28 × 10−10 to 6.65 × 10−9 cm2 s−1. These results show that both k0 and D increase with temperature in the studied DESs. In addition, better kinetic parameters for the DES with ethylene glycol as hydrogen bond donor means that this could be evaluated favorably as both solvents and electrolytes for redox flow cells
Investigation of ammonium- and phosphonium-based deep eutectic solvents as electrolytes for a non-aqueous all-vanadium redox cell
The charge/discharge characteristics for vanadium acetylacetonate in deep eutectic solvents were evaluated using an H-cell with an anion-exchange membrane separator for the first time. Coulombic (CE) and energy efficiencies (EE) of the electrolyte containing V(acac)3/0.5 M TEABF4 in DES3 (a hydrogen bonded eutectic between choline chloride and ethylene glycol) were obtained as 49-52% and 25-31%, respectively, when charging from 0 to 50% of theoretical maximum state-of-charge for 12 cycles. The low CE may be due to the crossover of the active species through the separator, or to the loss of active vanadium due to a parasitic reaction. However, the CE was similar to that for acetonitrile (CH3CN) indicating the promise of DESs as suitable electrolytes for future evaluation. Charge and discharge voltages are respectively higher and lower than the formal cell potential obtained by voltammetry. Ohmic drop in the DES results from the low conductivity of the electrolyte and the relatively large distance between the two electrodes in the H-cell. Further studies require investigation in a flow cell with analyses of polarization curves and impedance to determine the loss mechanisms in sufficient detail
Enzymatic esterification of eugenol and benzoic acid by a novel chitosan-chitin nanowhiskers supported Rhizomucor miehei lipase: Process optimization and kinetic assessments
A biotechnological route via enzymatic esterification was proposed as an alternative way to synthesize the problematic anti-oxidant eugenyl benzoate. The new method overcomes the well-known drawbacks of the chemical route in favor of a more sustainable reaction process. The present work reports a Box-Behnken design (BBD) optimization process to synthesize eugenyl benzoate by esterification of eugenol and benzoic acid catalyzed by the chitosan-chitin nanowhiskers supported Rhizomucor miehei lipase (RML-CS/CNWs). Effects of four reaction parameters: reaction time, temperature, substrate molar ratio of eugenol: benzoic acid and enzyme loading were assessed. Under optimum conditions, a maximum conversion yield as high as 66% at 50 °C in 5 h using 3 mg/mL of RML-CS/CNWs, and a substrate molar ratio (eugenol: benzoic acid) of 3:1. Kinetic assessments revealed the RML-CS/CNWs catalyzed the reaction via a ping-pong bi–bi mechanism with eugenol inhibition, characterized by a Vmax of 3.83 mM min-1. The Michaelis–Menten constants for benzoic acid (Km,A) and eugenol (Km,B) were 34.04 and 138.28 mM, respectively. The inhibition constant for eugenol (Ki,B) was 438.6 mM while the turnover number (kcat) for the RML-CS/CNWs-catalyzed esterification reaction was 40.39 min-1. RML-CS/CNWs were reusable up to 8 esterification cycles and showed higher thermal stability than free RML
Abnormalities of the Small Bowel in Chronic Non-Infective Diarrhea: a Histopathological Study
Background: The incidence of chronic non-infectious diarrhea cases is increasing in line with the developments of medical technology and science. The objective of this study was to uncover the histopathologic abnormalities of the small bowel in cases of chronic non-infectious diarrhea. Methods: All chronic non-infectious diarrhea patients in Cipto Mangunkusumo Hospital from 1996 until 2000 were included in this study. For the control group, we used 37 endoscopically-normal patients with functional dyspepia with the same characteristics (sex and age). All of the patients underwent gastroduodeno-jejunoscopic and ileocolonoscopic examinations. Patients with infection were excluded from this study. Biopsies were taken from the duodenal bulb, descending duodenum, jejunum near the Treitz ligament, terminal ileum, and colon. Histopathological tests were performed on all of the biopsies. Result: Histopathological examination was carried out on 31 patients and 37 control patients. In the duodenal bulb, the width of villi, lymphocyte infiltration, eosinophil infiltration, stage of inflammation, and polymorphonuclear cells infiltration were all lower in the chronic non-infectious diarrhea group than in the control group (p < 0.01). In the descending part of duodenum and jejunum, lymphocyte infiltration, the stage of inflammation, and polymorphonuclear cell infiltration were found to be higher in the chronic non-infectious diarrhea group than in the control group (p< 0.01). Within the terminal ileum, lymphocyte infiltration, the stage of inflammation and lymphoid follicle hyperplasia were found to be higher in the chronic non-infectious diarrhea group than in the control group (p< 0.01). Conclusion: Histopathologically, increased lymphocyte infiltration, inflammation and lymphoid follicle hyperplasia were discovered in specified areas of small intestine in chronic non-infectious diarrhea patients
Estimating the environmental impacts of global lithium-ion battery supply chain: A temporal, geographical, and technological perspective
A sustainable low-carbon transition via electric vehicles will require a comprehensive understanding of lithium-ion batteries’ global supply chain environmental impacts. Here, we analyze the cradle-to-gate energy use and greenhouse gas emissions of current and future nickel-manganese-cobalt and lithium-iron-phosphate battery technologies. We consider existing battery supply chains and future electricity grid decarbonization prospects for countries involved in material mining and battery production. Currently, around two-thirds of the total global emissions associated with battery production are highly concentrated in three countries as follows: China (45%), Indonesia (13%), and Australia (9%). On a unit basis, projected electricity grid decarbonization could reduce emissions of future battery production by up to 38% by 2050. An aggressive electric vehicle uptake scenario could result in cumulative emissions of 8.1 GtCO2eq by 2050 due to the manufacturing of nickel-based chemistries. However, a switch to lithium iron phosphate-based chemistry could enable emission savings of about 1.5 GtCO2eq. Secondary materials, via recycling, can help reduce primary supply requirements and alleviate the environmental burdens associated with the extraction and processing of materials from primary sources, where direct recycling offers the lowest impacts, followed by hydrometallurgical and pyrometallurgical, reducing greenhouse gas emissions by 61, 51, and 17%, respectively. This study can inform global and regional clean energy strategies to boost technology innovations, decarbonize the electricity grid, and optimize the global supply chain toward a net-zero future
Academic freedom: in justification of a universal ideal
This paper examines the justification for, and benefits of, academic freedom to academics, students, universities and the world at large. The paper surveys the development of the concept of academic freedom within Europe, more especially the impact of the reforms at the University of Berlin instigated by Wilhelm von Humboldt. Following from this, the paper examines the reasons why the various facets of academic freedom are important and why the principle should continue to be supported
Novel Coronin7 interactions with Cdc42 and N-WASP regulate actin organization and Golgi morphology
YesThe contribution of the actin cytoskeleton to the unique architecture of the Golgi complex is manifold.
An important player in this process is Coronin7 (CRN7), a Golgi-resident protein that stabilizes F-actin
assembly at the trans-Golgi network (TGN) thereby facilitating anterograde trafficking. Here, we
establish that CRN7-mediated association of F-actin with the Golgi apparatus is distinctly modulated
via the small Rho GTPase Cdc42 and N-WASP. We identify N-WASP as a novel interaction partner of
CRN7 and demonstrate that CRN7 restricts spurious F-actin reorganizations by repressing N-WASP
‘hyperactivity’ upon constitutive Cdc42 activation. Loss of CRN7 leads to increased cellular F-actin
content and causes a concomitant disruption of the Golgi structure. CRN7 harbours a Cdc42- and
Rac-interactive binding (CRIB) motif in its tandem β-propellers and binds selectively to GDP-bound
Cdc42N17 mutant. We speculate that CRN7 can act as a cofactor for active Cdc42 generation. Mutation
of CRIB motif residues that abrogate Cdc42 binding to CRN7 also fail to rescue the cellular defects in
fibroblasts derived from CRN7 KO mice. Cdc42N17 overexpression partially rescued the KO phenotypes
whereas N-WASP overexpression failed to do so. We conclude that CRN7 spatiotemporally influences
F-actin organization and Golgi integrity in a Cdc42- and N-WASP-dependent manner.This work was supported by SFB 670 and DFG NO 113/22. K.B. was supported by a fellowship from the NRW International Graduate School “From Embryo to Old Age: the Cell Biology and Genetics of Health and Disease” (IGSDHD), Cologne
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