30 research outputs found
Effect of <i>ompA</i> inactivation on natural transformation on 5% agar plates.
No full text<p>Overnight grown (13 hr) <i>E. coli</i> BW25113 (square symbols) and JW0940 (BW25113::<i>ompA</i>::kan, circle symbols) were inoculated (1%) in 100 ml of fresh LB. While the cultures were incubated in a shaker with a speed of 150 rpm at 30°C, the optical density at OD<sub>600</sub> was measured periodically (open symbols). Transformation was performed as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0059019#s4" target="_blank">Materials and Methods</a>. The mixture of the cell culture and pDsRED was plated on selective plates with 5% agar. Viable counts were measured by plating diluted culture on the same plates without any antibiotics. Transformation frequency (filled symbols) was calculated by dividing the number of transformants per ml by the number of viable counts per ml. Each point denotes an average of 4 samples. Error bars denote standard deviation. <sup>*</sup> P value ≦ 0.05; <sup>**</sup> P value ≦ 0.01.</p
The Electrochemistry of Ag in Deep Eutectic Solvents
No full textA fundamental study in to the correlation of nucleation mechanism with deposit morphology using silver salts as a well behaved system has been carried out in deep eutectic solvents i.e. mixtures of choline chloride (ChCl) with firstly ethylene glycol and secondly urea in a 1:2 molar ratio. The nucleation and growth kinetics of silver deposition were measured as a function of liquid type, deposition potential and silver salt type. The effect of different additives including surfactants (SDS and CTAB) and aqueous brightener (cresyl fast violet-CFV and crystal violet-CV) on nucleation was determined using electrochemical techniques such as cyclic voltammetery and chronoamperometery. Electrogravimetric studies were carried out using electrochemical quartz crystal microbalance (EQCM) to correlate the deposited mass of silver with findings from the electrochemical studies in both solvents.
A qualitative evaluation of the nucleation and growth mechanism and quantitative estimation of the kinetic parameters of silver electrocrystallization process was carried out using the existing theoretical formalisms. A computer simulation was used to extract the nuclear number density, rate of nucleation, diffusion co-efficient and influence of the double layer charging by fitting the whole potentiostatic current transients using a ‘non-linear best fitting’ method. The analysis of the development of the surface by nucleation and growth of the silver deposition in real time was studied using the ex-situ AFM and in-situ DHM. The latter of these was the first demonstration of this technique for the study of nucleation and growth mechanism of metal deposition and the results showed good agreement with the ex-situ AFM findings
GALACTIC DIFFUSE GAMMA RAYS—RECALCULATION BASED ON NEW MEASUREMENTS OF THE COSMIC ELECTRON SPECTRUM
No full textImpact of carbon emissions sources on life expectancy in Asia and the Pacific region
No full textThis study aligns with the 2030 United Nations Sustainable Development Goals 3 and 11, which aim to “ensure healthy lives and promote well-being for all at all ages” and “make cities and human settlements inclusive, safe, resilient, and sustainable”. The study objectives are to (i) explore the impact of different sources of carbon emissions on life expectancy; (ii) evaluate if the impact differs across income groups, and (iii) determine if life expectancy is persistent. It contributes to the health-environment literature but differs from two standpoints. First, it uses two essential sources of carbon emissions: liquid and solid fuels. Second, it engages robust analyses comprising the full sample and sub-samples of income groups to further interrogate this intrinsic relationship. For this purpose, an unbalanced sample of 36 countries from Asia and the Pacific region (2005–2010) is used, and for robust analyses, three econometric methods: bootstrap ordinary least squares (BOLS), instrumental variables (IV), and system generalized method of moments (GMM) are implemented. Empirical results reveal that: (1) liquid and solid fuel emissions exert significant negative outcomes, (2) liquid fuel emissions exhibit the most adverse effect, (3) life expectancy is persistent, and (4) impact of liquid and solid fuel emissions on life expectancy across the income groups is diverse. These findings suggest that the management authorities of Asia and the Pacific region need to devise prudent and effective policies concerning human health and carbon emissions while allocating sufficient budget to the health sector to rescue more lives and, thereby, lengthen the life expectancy in the region.</p
Infant mortality rate and nonrenewable energy consumption in Asia and the Pacific: the mediating role of carbon emissions
No full textThis study aligns with the 2030 United Nations Sustainable Development Goal 3 which aims to “ensure healthy lives and promote well-being for all at all ages”. It contributes to the nascent literature stream on energy-health dynamics by introducing a holistic theoretical model to empirically examine the mediation effect of carbon emissions on the relationship between nonrenewable energy and infant mortality rate. Using an unbalanced panel data on 42 Asia and the Pacific countries from 2005 to 2015 and deploying the structural equation modelling (SEM) approach, the empirical results are surmised as follows: (i) for the full sample, nonrenewable energy indirectly increases infant mortality rate through increasing carbon emissions. In other words, carbon emissions play a partial mediation role between nonrenewable energy and infant mortality rate; and (ii) for the different income groups, carbon emissions show varying mediation effects. For example, the mediation effect of carbon emissions in lower-middle and upper-middle income countries are found to be similar to those of the full sample of countries. Therefore, based on these findings, we conclude that nonrenewable energy is an essential determinant of infant mortality rate. Policy recommendations are put forward.</p
Infant mortality rate and nonrenewable energy consumption in Asia and the Pacific: the mediating role of carbon emissions
No full textThis study aligns with the 2030 United Nations Sustainable Development Goal 3 which aims to “ensure healthy lives and promote well-being for all at all ages”. It contributes to the nascent literature stream on energy-health dynamics by introducing a holistic theoretical model to empirically examine the mediation effect of carbon emissions on the relationship between nonrenewable energy and infant mortality rate. Using an unbalanced panel data on 42 Asia and the Pacific countries from 2005 to 2015 and deploying the structural equation modelling (SEM) approach, the empirical results are surmised as follows: (i) for the full sample, nonrenewable energy indirectly increases infant mortality rate through increasing carbon emissions. In other words, carbon emissions play a partial mediation role between nonrenewable energy and infant mortality rate; and (ii) for the different income groups, carbon emissions show varying mediation effects. For example, the mediation effect of carbon emissions in lower-middle and upper-middle income countries are found to be similar to those of the full sample of countries. Therefore, based on these findings, we conclude that nonrenewable energy is an essential determinant of infant mortality rate. Policy recommendations are put forward.</p
Comprehensive Investigation on Service Aged Power Transformer Insulating Oil After Decades of Effective Performance in Field
No full textLiquid-based dielectrics have been used in the electrical power components for high voltage insulation and cooling purposes for over a century. Numerous condition monitoring techniques are used for its performance analysis. Dielectric breakdown event of insulting oil is a key failure mode which adversely impacts the transformer performance. Transformer oil is a prime source of fault diagnosis of transformer and its condition monitoring. Insulation condition of the oil, acidity, chemical degradation that occurred over the period of time can be detected by modern spectroscopic techniques. Fourier transform infrared spectroscopy (FTIR) has acquired exceptional importance in determining the chemical degradation of the oil for utility professionals. In this work, service aged oil specimens were taken from a transformer with a successful operating life of 37 years in order to investigate the reason behind its internal faults. Various testing techniques such as breakdown voltage, frequency-domain dielectric spectroscopy, UV–visible spectroscopy, charge migration and mobility and FTIR were used for comprehensive analysis of oil condition. For comparative performance analysis, pristine samples of same oil were procured from the identical manufacturer. More emphasis was laid on the capability of FTIR to access the oil condition. The experimental findings of this study could provide a valuable insight to researchers and condition monitoring engineers in this field
Stepwise Regression Model for Predicting Cd Concentration (Y) in Edible Part of Pak choi based on Soil Properties.
No full texta<p>Cd<sub>T</sub> and Zn<sub>T</sub> refer to the total Cadmium and Zinc concentrations.</p>b<p>Superscripts * and ** indicate significant levels of probability at 0.05 and 0.01, respectively.</p><p>Stepwise Regression Model for Predicting Cd Concentration (Y) in Edible Part of Pak choi based on Soil Properties.</p
Mehlich-3 Extractable Cd Contents (mg kg<sup>−1</sup>) in Seven Chinese Soils at the onset of Containerized Experiment after Aging of 1 year.
No full text<p>Mean values followed by different letters within the same column are significantly different at <i>P</i> <0.05.</p><p>Mehlich-3 Extractable Cd Contents (mg kg<sup>−1</sup>) in Seven Chinese Soils at the onset of Containerized Experiment after Aging of 1 year.</p
