A rapid and simple method for small-scale DNA extraction inAgavaceae and other tropical plants

2002 ◽  
Vol 20 (3) ◽  
pp. 299-299 ◽  
Author(s):  
Miguel Keb-Llanes ◽  
Gerardo González ◽  
Bartolomé Chi-Manzanero ◽  
Diógenes Infante
2018 ◽  
Vol 1 (3) ◽  
pp. 27 ◽  
Author(s):  
Džiuginta Jakočiūnė ◽  
Arshnee Moodley

Bacteriophages (phages) are intensely investigated as non-antibiotic alternatives to circumvent antibiotic resistance development as well as last resort therapeutic options against antibiotic resistant bacteria. As part of gaining a better understanding of phages and to determine if phages harbor putative virulence factors, whole genome sequencing is used, for which good quality phage DNA is needed. Traditional phage DNA extraction methods are tedious and time consuming, requiring specialized equipment e.g., an ultra-centrifuge. Here, we describe a quick and simple method (under four hours) to extract DNA from double stranded DNA (dsDNA) phages at titers above 1.0 × 1010 plaque-forming units (PFU)/mL. This DNA was suitable for library preparation using the Nextera XT kit and sequencing on the Illumina MiSeq platform.


Author(s):  
W. F. Carey ◽  
G. J. Williamson

On plants in which gases are processed, the gases are often brought into direct contact with water—usually in packed towers. The purpose may be to cool a hot gas, to increase the humidity of a gas, or, in the well-known special case of water-cooling towers, to cool water by contact with atmospheric air. These processes involve simultaneous transfers of sensible heat and water vapour, and existing methods of analysis are complex and laborious, except for the cooling of water, for which Merkel's total-heat method has long been available. Merkel's approximate solution offers the engineer a simple method of working out, for any operating conditions, the amount of heat transferred and the “driving force” available for transferring it. The present paper generalizes the total-heat method and, with a permissible sacrifice in accuracy, preserves the essential simplicity of the water-cooling treatment for gas-cooling and humidification processes. To complete the design of a packed tower, a knowledge is required of the characteristics of the packing. Information obtained in small towers is given for a number of packings, and a worked example shows how to apply the method of treatment, and the packing data presented, to the design of a large plant tower.


Author(s):  
Vanka Bala Murali Krishna ◽  
Sandeep Vuddanti

Abstract Research on Self –excited induction generator (SEIG) brings a lot of attentions in the last three decades as a promising solution in distributed generation systems with low cost investment. There are two important fixations to attend in the operation of SEIG based systems, a) excitation and b) voltage regulation. Many procedures are reported regarding selection of excitation capacitance in the literature, based on state-state analysis, dynamic modeling, empirical formulas and machine parameters which involve various levels of complexity in findings. Moreover, the voltage regulation is the main challenge in implementation of SEIG based isolated systems. To address this problem, many power electronic-based schemes are proposed in the literature and but these solutions have few demerits importantly that additional cost of equipment and troubles due to failure of protection schemes. In particular, the installation of SEIG takes place at small scale in kW range in remote/rural communities which should not face such shortcomings. Further in case of off-grid systems, the maximum loading is fixed based on connected rating of the generator. This paper presents the various methods to find excitation capacitance and illustrates an experimental investigation on different possible reactive power compensation methods of delta connected SEIG and aimed to identify a simple method for terminal voltage control without power electronics. In this experimental work, the prime-mover of the generator is a constant speed turbine, which is the emulation of a micro/pico hydro turbine. From the results, it is found that a simple delta connected excitation and delta configured reactive power compensation limits voltage regulation within ±6% while maintaining the frequency of ±1%, which make feasible of the operation successfully in remote electrification systems.


2005 ◽  
Vol 347 (2) ◽  
pp. 333-335 ◽  
Author(s):  
José Luis Ruiz-Barba ◽  
Antonio Maldonado ◽  
Rufino Jiménez-Díaz
Keyword(s):  

2006 ◽  
Vol 55 (9) ◽  
pp. 1187-1191 ◽  
Author(s):  
Lisa J. Griffiths ◽  
Martin Anyim ◽  
Sarah R. Doffman ◽  
Mark Wilks ◽  
Michael R. Millar ◽  
...  

Newer methods such as PCR are being investigated in order to improve the diagnosis of invasive aspergillosis. One of the major obstacles to using PCR to diagnose aspergillosis is a reliable, simple method for extraction of the fungal DNA. The presence of a complex, sturdy cell wall that is resistant to lysis impairs extraction of the DNA by conventional methods employed for bacteria. Numerous fungal DNA extraction protocols have been described in the literature. However, these methods are time-consuming, require a high level of skill and may not be suitable for use as a routine diagnostic technique. Here, a number of extraction methods were compared: a freeze–thaw method, a freeze–boil method, enzyme extraction and a bead-beating method using Mini-BeadBeater-8. The quality and quantity of the DNA extracted was compared using real-time PCR. It was found that the use of a bead-beating method followed by extraction with AL buffer (Qiagen) was the most successful extraction technique, giving the greatest yield of DNA, and was also the least time-consuming method assessed.


2010 ◽  
Vol 11 (9) ◽  
pp. 3149-3157 ◽  
Author(s):  
Ibrahim A. Arif ◽  
Mohammad A. Bakir ◽  
Haseeb A. Khan ◽  
Anis Ahamed ◽  
Ahmad H. Al Farhan ◽  
...  

2019 ◽  
Author(s):  
Christian Barthlott ◽  
Andrew I. Barrett

Abstract. The mesoscale convective system (MCS) that affected Germany at Pentecost 2014 (9 June 2014) was one of the most severe for decades. However, the predictability of this system was very low as the operational deterministic and ensemble prediction systems failed to predict the event with sufficiently long lead times. We present hindcasts of the event using the COnsortium for Small-scale MOdeling (COSMO) model at convection-permitting (2.8 km) resolution on a large (1668 × 1807 km) grid, which allowed us to simulate the whole life cycle of the system originating from the French Atlantic coast. Results show that this model configuration successfully reproduces the convective events of that day. However, the low predictability of the event was evident by the surprisingly large impact of tiny changes to the model domain. We systematically shifted the model domain by one grid point in eight different directions, from which three did not simulate any convection over Germany. The analyses show that no important differences in domain-averaged initial conditions nor in the preconvective environment ahead of the convective system exist. That one-third of these seemingly identical initial conditions fails to produce any convection over Germany is intriguing. The main reason for the different model results seems to be the proximity of the track of the initial convective system to the coast and colder sea surface. The COSMO model simulates small horizontal displacements of the precursors of the MCS which then determine if the cells dissipate close to the sea or reach a favourable area for convective development over land and further evolve into an MCS. This study demonstrates the potentially huge impact of tiny model domain shifts on forecasting convective processes in this case, which suggests that the inclusion of this simple method in convective-scale ensemble forecasting systems should be evaluated for different cases, models and weather regimes.


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