Hydrostatic differential meter of local density of natural waters

Variants of constructing meters of local density of natural waters in deep-water instruments are proposed. In the first variant, the density of water is determined as the sum of the density of the reference liquid in a vertical tube with access in the middle of the tube of external pressure and the weighted sum of the readings of differential pressure sensors at the ends of the tube. The second version contains two identical basic or simplified meters with different densities of the reference liquid. In the third variant, n primary meters are used, from which n sub-bands or 2 С n results of pairwise measurements are formed. In the fourth version, one or more primary or simplified meters are used, which are adjusted to the measured density by changing the temperature.

Pengaruh konsentrasi starter dan macam buah terhadap karakteristik kefir air

Water kefir is a probiotic drink as a result of fermentation by lactobacillus acid bacteria, acetobacter and yeast. Fruits and other ingredients could be added to obtain water kefir with specific flavor and aroma. This research aims to observe the effect of starter concentration and kind of fruit used on the characteristics of water kefir, and to determine the best combination preferred by the panelists. This study used two factorial randomized design with three repetitions. The factors used are the starter concentration (5 %, 8 %, and 11 %) and the kind of fruit used (snake fruit, pineapple, and papaya). Results showed that different starter concentration had an effect on brix, pH, alcohol content and density of water kefir, while different kinds of fruit had an effect on brix. Based on organoleptic test the most preferred water kefir is pineapple water kefir with 8 % starter concentration.

Fluorinated oil-surfactant mixtures with the density of water: artificial cells for synthetic biology

Water-in-oil emulsions provide matrices for compartments that have many uses in diversity science. However, hydrophobic species are frequently incompatible with biological systems. For this reason, fluorinated matrices are often sought, since fluorinated species are neither hydrophilic nor hydrophobic; they therefore do not interact with most biomolecules. However, most fluorinated oils have densities much higher than the density of water (1 g/ml). Consequently, water droplets float in fluorinated oils, aggregating near their surfaces. This facilitates droplet-droplet collision and fusion, exposing droplets to air interfaces and making their manipulation difficult. Here, we report the synthesis, characterization, and use of fluorinated polysiloxane oils that have densities close to the density of water. These, with a non-ionic fluorosilicone surfactant, produce thermostable water-in-oil emulsions that neither float nor sink. We show how droplets in these emulsions can host many biological processes, including PCR, DNA origami, rolling circle amplification (RCA), and Taqman ® assays. Further, oil-diffusible reagents can initiate reactions within the droplets. The droplets can also be used with unnatural DNA emerging from synthetic biology, including DNA built from artificially expanded genetic information systems (AEGIS) with six nucleotide "letters".

Equids engineer desert water availability

Megafauna play important roles in the biosphere, yet little is known about how they shape dryland ecosystems. We report on an overlooked form of ecosystem engineering by donkeys and horses. In the deserts of North America, digging of ≤2-meter wells to groundwater by feral equids increased the density of water features, reduced distances between waters, and, at times, provided the only water present. Vertebrate richness and activity were higher at equid wells than at adjacent dry sites, and, by mimicking flood disturbance, equid wells became nurseries for riparian trees. Our results suggest that equids, even those that are introduced or feral, are able to buffer water availability, which may increase resilience to ongoing human-caused aridification.

Gamma-Ray Sensor Using YAlO3(Ce) Single Crystal and CNT/PEEK with High Sensitivity and Stability under Harsh Underwater Conditions

A new gamma-ray sensor, which could be employed in harsh underwater conditions, was developed using YAlO3(Ce) single crystal and carbon nanotube reinforced polyetheretherketone (CNT/PEEK). The sensor is compact, highly sensitive and stable, by providing real-time gross counts and an accumulated spectrum for fresh, saline, or contaminated water conditions. The sensor was tested in a water tank for quantification of the limit of detections. The Φ51 × 51 mm2 YAlO3(Ce) crystal exhibits a nearly perfect proportionality with a correlation of over 0.999 in terms of light yield per energy and possesses a high energy resolution. The chemically stable CNT/PEEK window material further enhances the detection efficiency by minimizing the background counts from penetrating gamma-rays. Data timeliness was obtained for regulation-based minimum detectable activity targets within 300 s. For a source-detector distance of up to 300 mm in water, the gross counts demonstrate the existence of radionuclides (Cs-137 and Co-60), owing to their higher efficiency (max. ~15 times) than those of the photopeak counts. Such differences between efficiency values are more likely in water than in air because of the high density of water, resulting in an increased build-up of scattered photons. The proposed sensor is suitable for autonomous underwater systems.