251 research outputs found

    A global atlas of potential thermal refugia for coral reefs generated by internal gravity waves

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    Coral reefs are highly threatened by ocean warming and the majority are likely to be lost in less than three decades. A first step in maximizing reef conservation through this period is to identify where coral reefs are more likely to survive rising ocean temperatures, such as locations that experience lower temperatures than surrounding regions, high temperature variability, and high food supply. Such conditions are often the result of naturally occurring internal gravity waves (IGWs), oscillatory subsurface disturbances that can entrain cooler and/or nutrient-rich subsurface waters and cause high frequency temperature fluctuations. These features usually remain undetected because they occur subsurface and at spatial scales of O(1 km) and smaller. To shed light on where IGWs are likely to impact temperature conditions within coral reef regions, we present an analysis of data from the LLC4320, a massive high resolution (1/48˚; < 2.5 km) numerical global ocean simulation. The results highlight strong regional differences in the incidence of IGW-induced temperature variability. The analysis also reveals that thermal refugia are limited to depths where high temperature variability coincides with the actual reef depth and may not persist year-round. Assuming 10-m depth as the nominal reef depth, reef regions likely to benefit from IGW-induced cooling occur in SE Asia and the Coral Triangle, the Galápagos, along the Pacific shelf of Central America, and isolated locations worldwide. Such refugia are rare within the Atlantic reef sector. An interactive global atlas showing the results of this study has been made freely available online at https://ncar.github.io/coral-viz/

    A vapor based microfluidic flow regulator

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    We introduce a flow regulating technology that uses trapped air bubbles in a hydrophobic microfluidic channel. We present basic designs for flow regulators and flow valves using trapped air. Experiments have successfully demonstrated the capability of this technique for delivering constant and varying flow rate, and for on-off valving. This approach to valving provides a simple, yet effective way to monolithically integrate flow and valve control on polymer Lab-on-Chip devices

    Fast-lysis cell traps for chemical cytometry

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    Electrically addressable cell traps were integrated with capillary electrophoresis for the analysis of the contents of single adherent cells. Electrodes composed of indium tin oxide were patterned on a glass surface followed by formation of topographical cell traps using 1002F photoresist. Single cells trapped in the holes could be lysed in less than 66 ms by applying a brief electric field (10 ms) across the electrode beneath the cell and the ground electrode placed in the aqueous media above the cell traps. The gas formed during cell lysis remained localized within the cavity formed by the 1002F photoresist. The retention of the gas in the cell trap enabled the cell traps to be coupled to an overlying capillary without blockage of the capillary. Single cells cultured in the traps were loaded with fluorescein and Oregon Green and then electrically lysed. By simultaneous application of an electric field to the capillary, the cell’s contents were loaded into the capillary and electrophoretically separated. Orgeon Green and fluorescein from a single cell were fully resolved in less than two minutes. The use of a single patterned electrode beneath the 1002F cell trap yielded a simple easily fabricated design that was robust when immersed in aqueous solutions. Moreover, the design can easily be scaled up to create arrays of adherent cells for serial analyses using a single capillary or for parallel analysis by mating to an array of capillaries. Enhancing the rate of analysis of single adherent cells would enable a greater understanding of cellular physiology

    TnseqDiff: identification of conditionally essential genes in transposon sequencing studies

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    Abstract Background Tn-Seq is a high throughput technique for analysis of transposon mutant libraries to determine conditional essentiality of a gene under an experimental condition. A special feature of the Tn-seq data is that multiple mutants in a gene provides independent evidence to prioritize that gene as being essential. The existing methods do not account for this feature or rely on a high-density transposon library. Moreover, these methods are unable to accommodate complex designs. Results The method proposed here is specifically designed for the analysis of Tn-Seq data. It utilizes two steps to estimate the conditional essentiality for each gene in the genome. First, it collects evidence of conditional essentiality for each insertion by comparing read counts of that insertion between conditions. Second, it combines insertion-level evidence for the corresponding gene. It deals with data from both low- and high-density transposon libraries and accommodates complex designs. Moreover, it is very fast to implement. The performance of the proposed method was tested on simulated data and experimental Tn-Seq data from Serratia marcescens transposon mutant library used to identify genes that contribute to fitness in a murine model of infection. Conclusion We describe a new, efficient method for identifying conditionally essential genes in Tn-Seq experiments with high detection sensitivity and specificity. It is implemented as TnseqDiff function in R package Tnseq and can be installed from the Comprehensive R Archive Network, CRAN.https://deepblue.lib.umich.edu/bitstream/2027.42/137673/1/12859_2017_Article_1745.pd

    Characterization of the laser-based release of micropallets from arrays

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    The micropallet array system uses a pulsed laser to release pallets tens of microns to hundreds of microns in size from a larger array, enabling selective isolation of single cells adherent to the pallets. In this study, the laser-based release of pallets was characterized with respect to pallet array and laser parameters. The threshold laser energy required for pallet release increased linearly with the area of the pallet in contact with the underlying glass substrate. The spacing of the pallets within an array as well as the thickness or height of the pallet did not impact the energy required to release a pallet. Delivery of multiple laser pulses decreased the energy/pulse required for pallet release when the pallets were 100 microns or greater on a side. In addition to the square pallets, complex structures such as cantilevers and spirals could be released without damage using the pulsed laser. Identification of the pallet-array variables influencing the energy required for pallet release as well as strategies to minimize this energy will prove critical in optimizing the release of pallets with cells on the arrays

    Пути инновационного развития Автономной Республики Крым

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    Целью работы является изучение состояния и перспектив дальнейшего развития инновационной активности в Автономной Республике Крым

    Underutilization of information and knowledge in everyday medical practice: Evaluation of a computer-based solution

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    <p>Abstract</p> <p>Background</p> <p>The medical history is acknowledged as the <it>sine qua non </it>for quality medical care because recognizing problems is pre-requisite for managing them. Medical histories typically are incomplete and inaccurate, however. We show here that computers are a solution to this issue of information gathering about patients. Computers can be programmed to acquire more complete medical histories with greater detail across a range of acute and chronic issues than physician histories.</p> <p>Methods</p> <p>Histories were acquired by physicians in the usual way and by a computer program interacting directly with patients. Decision-making of what medical issues were queried by computer were made internally by the software, including determination of the chief complaint. The selection of patients was from admissions to the Robert-Bosch-Hospital, Stuttgart, Germany by convenience sampling. Physician-acquired and computer-acquired histories were compared on a patient-by-patient basis for 45 patients.</p> <p>Results</p> <p>The computer histories reported 160 problems not recorded in physician histories or slightly more than 3.5 problems per patient. However, physicians but not the computer reported 13 problems. The data show that computer histories reported problems across a range of organ systems, that the problems detected by computer but not physician histories were both acute and chronic and that the computer histories detected a significant number of issues important for preventing further morbidity.</p> <p>Conclusion</p> <p>A combination of physician and computer-acquired histories, in non-emergent situations, with the latter available to the physician at the time he or she sees the patient, is a far superior method for collecting historical data than the physician interview alone.</p
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