The metagenomics of biosilicification: causes and effects

In order to determine the links between geochemical parameters controlling the formation of silica sinter in hot springs and their associated microbial diversity, a detailed characterisation of the waters and of in situ-grown silica sinters was combined with molecular phylogenetic analyses of the bacterial communities in Icelandic geothermal environments. At all but one site, the microorganisms clearly affected, and in part controlled, the formation of the macroscopic textures and structures of silica sinter edifices. In addition, the class and genera level phylogenetic diversity and distribution appeared to be closely linked to variations in temperature, salinity and pH regimes

Application of Vertical Electrical Sounding and Horizontal Profiling Methods to Decipher the Existing Subsurface Stratification in River Segen Dam Site, Tigray, Northern Ethiopia

The study area Segen river dam site is situated in the southeastern zone of Tigray National Regional State in between Hintalo Wajirat and Enderta weredas. It is geographically located at 37P between 541400 to 542600 UTME Latitude and 1481600 to 1482600 UTMN Longitude about 35 km southwestern part of Mekelle, the capital of Tigray National Regional State. The study was conducted having an objective of the geophysical assessment to provide important subsurface geophysical information useful in evaluating the subsurface geological formations, geological structures,  cavities and others for the dam site under investigation. Ten Vertical Electical Sounding (VES) points along the two profile lines and a total of two Horizontal Profiling (EP) with a Wenner electrode array were collected. VES datas were entered to the computer and curves were plotted using IPI2win interpretation software. EP are entered into the computer and processed using Microsoft Office Excel and Golden Software Surfer V. 8. The VES results have shown that weak zones at VES 2, VES 3 and VES 4 along profile 1 and at VES 2, VES 3 and VES 5 along profile 2 where the depth goes no more 20 m deep in both profiles’ pseudo cross section except at VES 4 profile which extends up to 30 m deep. Similarly, the electrical resistivity profiling results also have shown that the weak zones extend no more than 20 m of depth. Hence, the result revealed that the investigation requires further core drilling investigations. Key words: vertical electrical sounding, horizontal profiling, subsurface, goephysical, dam, Segen, Tigray, Ethiopi

Tissue Processor Based PLC (Programmable Logic Controller)

Tissue Processor Tissue Processor consists of consists of several stages of dehydration, clearing, and paraffin infiltration.Phase dehydration to remove water content in tissues by immersion into alcohol. Clearing stage is the process of pulling out the alcohol content in the network by using a liquid xylol. Paraffin infiltration stages is the stage of filling cavities with liquid paraffin tissue. The purpose of this research is to modify the equipment that had broken before became an useful equipment that use basic controlled  PLC. This modification tool-making using the "one-group posttest design" by treatment of the instrument without first measuring the initial state, the results of treatment directly measured without comparison to a control group. Making the modification tool using PLC as the main controller throughout the series. The tool mechanical motion using DC motors and AC motors as well as the use of two sensors limit switch as the controller limits the motor movement. Based on the results obtained temperature measurement error with the largest value of 4.44% in paraffin heater tube 1 and the biggest error of 4.0% in paraffin heater tube 2. While the measurement time of each - each tube obtained the smallest error on the tube-to-one by 0 , 03%, and the biggest error of measurement contained in the tube to the fourth, fifth, sixth, eighth and tenth of 0.16%

Effect of Temperature on PH Meter Based on Arduino Uno with Internal Calibration

PH Meter is a device used to express the level of acidity or basicity possessed by a substance or solution. Normal pH has a value of 7 while the pH value> 7 indicates that the substance has alkaline properties while the pH value <7 indicates acidic properties. pH 0 shows a high degree of acidity, and pH 14 shows the highest degree of alkalinity. pH Meter reads the pH and temperature values ​​in a sample. The author uses glass electrodes as a pH sensor, DS18B20 as a temperature sensor and LCD to make pH and temperature values. This module is equipped with an internal calibration that is used to set the module to read the pH value properly and correctly using a pH buffer and equipped with internal storage and this module facilitates battery usage. Based on pH measurements on the module the error value in buffer 4 calibration is 5.39%, in buffer 7 is 1.76%, in buffer 10 is 1.04%. The highest error value in the measurement sample is 3.54% and the lowest error value is 0.03%. The temperature of the sample is very influential on the reading of the pH value because the higher the temperature the pH value also increases even though it is not so significant

The size and polydispersity of silica nanoparticles under simulated hot spring conditions

The nucleation and growth of silica nanoparticles in supersaturated geothermal waters was simulated using a flow-through geothermal simulator system. The effect of silica concentration ([SiO2]), ionic strength (IS), temperature (T) and organic additives on the size and polydispersity of the forming silica nanoparticles was quantified. A decrease in temperature (58 to 33°C) and the addition of glucose restricted particle growth to sizes <20 nm, while varying [SiO2] or ISdid not affect the size (30-35 nm) and polydispersity (±9 nm) observed at 58°C. Conversely, the addition of xanthan gum induced the development of thin films that enhanced silica aggregation

Founders Versus Descendants: Evidence Of The Taiwanese Publicly Traded Firms

This study investigates the performance of founder-controlled firms vis-à-vis firms controlled by founders’ descendants and relatives among Taiwanese publicly traded firms.  After adjusting for size, age, growth potential, financial leverage, and industry effects, we find that the Taiwanese descendant-controlled firms underperform the matching founder-controlled firms.  In searching for the potential reasons, we find that the average board size for the descendant-controlled firms is significantly larger than that of the founder-controlled firms.  In addition, the ratios of family-related supervisors and board members of the descendant-controlled firms are significantly higher than those of the matching founder-controlled firms.  While the significantly larger board size suggests a potential power struggle between the controlling family and the non-family related board members, the stronger family domination in the board of directors and supervisors for the descendant-controlled firms provides room for entrenchment and tunneling.  In light of the absence of large outside blockholders and relatively weaker legal protections, the minority shareholders of Taiwanese firms are dependent upon internal monitoring mechanisms to protect them from the expropriation of the controlling families.  However, our results indicate that family control has undermined the internal monitoring mechanism of the Taiwanese descendant-controlled firms

A historical Southern Ocean climate dataset from whaling ships’ logbooks

Historical ship logbooks provide vital historic meteorological observations in the Southern Ocean, one of the largest climate-data deficient regions on the Earth. Christian Salvesen Whaling Company logbooks from whaling ships operating in the Southern Ocean, starting from the 1930s through the 1950s, are examined. Meteorological information contained in these logbooks has been extracted to produce a historical climate dataset. We discuss various instructions recommended by the British Admiralty to observe and record weather conditions on board whaling ships. Statistical tests were used to flag erroneous values and corrections were made using neighbouring values. Meteorological parameters such as air pressure, air and sea temperature and wind force on the Beaufort scale were standardised, converting imperial to metric units. The data were structured according to the internationally accepted International Maritime Meteorological Archive (IMMA) format, which includes the most commonly reported meteorological variables, including the time, location, and ship-related meta-data. Hence, a readily accessible, error-corrected and standardised historical climate dataset of the Weddell Sea sector of the Southern Ocean is presented

Risk and Value in Privately Financed Health care Projects

An empirical study is presented to investigate the risk factors affecting the value for money that can be obtained from using the public-private partnership delivery system to develop social facility projects. Based on a model describing the main risks affecting a project, a linear regression analysis is conducted on a dataset of privately financed healthcare projects in the UK to explore the main factors that might have significant relationships with the annual unitary charge payment. The results reveal that the economic and political environment, the hospital capacity, the construction duration, and the concession period are significant factors of the price paid by the granting authority. The study confirms that the unitary charge is not only affected by investment, operations and financial lifecycle costs, but also by risk factors and the level of risk allocated to the private sponsors. The proposed methodology might help both public and private parties in improving PFI project's compensation design, in order to achieve a higher value in privately financed infrastructures. The given model might also support the process of better determining the amount of annual payment based on select drivers and appropriately transferred risk factor

Crystal structure of Li_2B_(12)H_(12): a possible intermediate species in the decomposition of LiBH_4

The crystal structure of solvent-free Li_2B_(12)H_(12) has been determined by powder X-ray diffraction and confirmed by a combination of neutron vibrational spectroscopy and first-principles calculations. This compound is a possible intermediate in the dehydrogenation of LiBH_4, and its structural characterization is crucial for understanding the decomposition and regeneration of LiBH_4. Our results reveal that the structure of Li_2B_(12)H_(12) differs from other known alkali-metal (K, Rb, and Cs) derivatives