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CO2BOLs are promising CCS solvents, whose mass transfer rates improve upon cooling. We show this unintuitive behavior is due to slow transport of reaction products from the gas–liquid interface, caused by shifts in reaction equilibria.

Advanced structured packing geometries fabricated with 3D printing were used for absorber CO2 capture with a liquid solvent. Compared to conventional packing, they had greatly enhanced (90–140%) effective surface areas and comparable hydrodynamics.

We have developed a new class of sodium carbonate/silicone composite sorbents that selectively capture carbon dioxide (CO2) and can purify biogas to natural gas pipeline-quality biomethane. These nontoxic composites can be three-dimensionally printed or extruded at low costs, can have high specific CO2 sorption rates (in excess of 5 μmol s-1 g-1 bar-1) and high selectivity due to their chemical mechanism, and can be regenerated with low-energy air stripping. Therefore, these composite sorbents combine the high selectivity of liquid sorbents with the high specific sorption rates and low regeneration energies found in many solid sorbents. We characterized these composite sorbents with X-ray computed tomography, scanning electron microscopy (SEM), and X-ray diffraction (XRD). Furthermore, we measured composite sorption capacities of up to 0.62 mol CO2 kg-1 and recorded breakthrough curves in a flow-through, fixed-bed reactor using both simulated biogas and locally sourced industrial biogas. Additional tests of the composite sorbent were carried out with pure CO2 in a sealed pressure drop apparatus. This experimental data was used to validate a numerical model of the setup and to simulate an industrial-scale biogas upgrading process. Finally, we performed a preliminary technoeconomic analysis for this upgrading process and found that this composite sorbent can upgrade biogas at a lower cost (∼$0.97 per GJ) than other currently implemented techniques.

Chronic inflammation that affects primarily metabolic organs, such as white adipose tissue (WAT), is considered as a major cause of human obesity-associated co-morbidities. However, the molecular mechanisms initiating this inflammation in WAT are poorly understood. By combining transcriptomics, ChIP-seq and modeling approaches, we studied the global early and late responses to a high-fat diet (HFD) in visceral (vWAT) and subcutaneous (scWAT) AT, the first being more prone to obesity-induced inflammation. HFD rapidly triggers proliferation of adipocyte precursors within vWAT. However, concomitant antiadipogenic signals limit vWAT hyperplastic expansion by interfering with the differentiation of proliferating adipocyte precursors. Conversely, in scWAT, residing beige adipocytes lose their oxidizing properties and allow storage of excessive fatty acids. This phase is followed by tissue hyperplastic growth and increased angiogenic signals, which further enable scWAT expansion without generating inflammation. Our data indicate that scWAT and vWAT differential ability to modulate adipocyte number and differentiation in response to obesogenic stimuli has a crucial impact on the different susceptibility to obesity-related inflammation of these adipose tissue depots. Electronic supplementary material The online version of this article (10.1007/s00018-020-03485-z) contains supplementary material, which is available to authorized users.

As part of the human microbiota, the fungus Candida albicans colonizes the oral cavity and other mucosal surfaces of the human body. Commensalism is tightly controlled by complex interactions of the fungus and the host to preclude fungal elimination but also fungal overgrowth and invasion, which can result in disease. As such, defects in antifungal T cell immunity render individuals susceptible to oral thrush due to interrupted immunosurveillance of the oral mucosa. The factors that promote commensalism and ensure persistence of C. albicans in a fully immunocompetent host remain less clear. Using an experimental model of C. albicans oral colonization in mice we explored fungal determinants of commensalism in the oral cavity. Transcript profiling of the oral isolate 101 in the murine tongue tissue revealed a characteristic metabolic profile tailored to the nutrient poor conditions in the stratum corneum of the epithelium where the fungus resides. Metabolic adaptation of isolate 101 was also reflected in enhanced nutrient acquisition when grown on oral mucosa substrates. Persistent colonization of the oral mucosa by C. albicans also correlated inversely with the capacity of the fungus to induce epithelial cell damage and to elicit an inflammatory response. Here we show that these immune evasive properties of isolate 101 are explained by a strong attenuation of a number of virulence genes, including those linked to filamentation. De-repression of the hyphal program by deletion or conditional repression of NRG1 abolished the commensal behaviour of isolate 101, thereby establishing a central role of this factor in the commensal lifestyle of C. albicans in the oral niche of the host.AUTHOR SUMMARYThe oral microbiota represents an important part of the human microbiota and includes several hundreds to several thousands of bacterial and fungal species. One of the most prominent fungus colonizing the oral cavity is the yeast Candida albicans. While the presence of C. albicans usually remains unnoticed, the fungus can under certain circumstances cause lesions on the lining of the mouth referred to as oral thrush or contribute to other common oral diseases such as caries. Maintaining C. albicans commensalism in the oral mucosa is therefore of utmost importance for oral health and overall wellbeing. While overt fungal growth and disease is limited by immunosurveillance mechanisms during homeostasis, C. albicans strives to survive and evades elimination from the host. Here, we show that while commensalism in the oral cavity is characterized by a restricted fungal virulence and hyphal program, enforcing filamentation in a commensal isolate is sufficient for driving pathogenicity and fungus-induced inflammation in the oral mucosa thwarting persistent colonization. Our results further support a critical role for specialized nutrient acquisition allowing the fungus to thrive in the nutrient poor environment of the squamous epithelium. Together, this work revealed key determinants of C. albicans commensalism in the oral niche.

We have developed polymer composite inks that may be three-dimensionally (3D) printed to produce new reactor designs for CO2 capture. These inks are composed of solid sodium carbonate particles dispersed within an uncured silicone and are printed using direct ink writing (DIW). After printing, the silicone is cured, and the structures are hydrated to form aqueous sodium carbonate domains dispersed throughout the silicone. These domains enable high CO2 absorption rates by creating domains with high surface area of solvent per unit volume in the printed structures. These results demonstrate an order-of-magnitude improvement in CO2 absorption rates relative to a liquid pool of sodium carbonate. The results from this class of composite inks demonstrate the potential for the use of 3D printing to shape new and advanced CO2 capture reactors.

We encapsulated six solvents with novel physical and chemical properties for CO2 sorption within gas-permeable polymer shells, creating Micro-Encapsulated CO2 Sorbents (MECS), to improve the CO2 absorption kinetics and handling of the solvents for postcombustion CO2 capture from flue gas. The solvents were sodium carbonate (Na2CO3) solution, uncatalyzed and with two different promoters, two ionic liquid (IL) solvents, and one CO2-binding organic liquid (CO2BOL). We subjected each of the six MECS to multiple CO2 absorption and regeneration cycles and measured the working CO2 absorption capacity as a function of time to identify promising candidate MECS for large-scale carbon capture. We discovered that the uncatalyzed Na2CO3 and Na2CO3-sarcosine MECS had lower CO2 absorption rates relative to Na2CO3-cyclen MECS over 30 min of absorption, while the CO2BOL Koechanol appeared to permeate through the capsule shell and is thus unsuitable. We rigorously tested the most promising three MECS (Na2CO3-cyclen, IL NDI...

Micro-Encapsulated CO2 Sorbents (MECS) are a promising technology for post-combustion carbon capture because they enable slow-reacting solvents like carbonate solution to compete with traditional amine solvents. Before scaling up MECS for pilot testing, modeling is needed to design a MECS absorber and quantify its size and energy penalty. To that end, a multi-scale model for MECS- that ranges from a single capsule to a 500 MWe power plant absorber- is developed and presented here. First, the individual capsule model is developed and fitted to experimental CO2 absorption data collected on a 0.1 g sample of capsules filled with sodium carbonate solution. This capsule model is then validated against data collected on a 25 g batch of capsules exposed to flue gas conditions in a fluidized column. This model is then scaled up to represent two absorber designs: a multi-stage, counter-flow fluidized bed and a hollow, cylindrical packed bed with radial gas flow. These two absorber bed models are first optimized for a 1 MWe pilot-scale absorber, and then optimized for a 500 MWe coal plant. This model predicts absorbers of similar dimensions and smaller energy penalties than previously modeled absorbers filled with amine solvent capsules. Furthermore, it is demonstrated here that a few reasonable improvements to capsule design would result in absorber sizes and energy penalties lower than those of a benchmark amine solvent tower. These results demonstrate that micro-encapsulated carbonate solution can compete with faster-acting amine solvents for post-combustion carbon capture.

Candida albicans is a commensal of human mucosae, but also one of the most common fungal pathogens of humans. Systemic infections caused by this fungus, mostly affecting immunocompromised patients, are associated to fatality rates as high as 50% despite the available treatments. In order to improve this situation, it is necessary to fully understand how C. albicans is able to cause disease and how it copes with the host defenses. Our previous studies have revealed the importance of the C. albicans gene MBF1 in virulence and ability to colonize internal organs of mammalian and insect hosts. MBF1 encodes a putative transcriptional regulator, and as such it likely has an impact in the regulation of C. albicans gene expression during host infection. Here, recent advances in RNA-seq technologies were used to obtain a detailed analysis of the impact of MBF1 on C. albicans gene expression both in vitro and during infection. MBF1 was involved in the regulation of several genes with a role in glycolysis and response to stress, particularly to nutritional stress. We also investigated whether an interaction existed between MBF1 and GCN4, a master regulator of response to starvation, and found that both genes were needed for resistance to amino acid starvation, suggesting some level of interaction between the two. Reinforcing this idea, we showed that the proteins encoded by both genes could interact. Consistent with the role of MBF1 in virulence, we also established that GCN4 was necessary for virulence in the mouse model of systemic infection as well as in the Galleria mellonella infection model.

Increasing absorber efficiency in aqueous amine CCS systems is one avenue to decrease capitol cost by reducing the overall size of the absorber column. One potential route to improve the absorber is by replacing conventional steel packing with custom designed packing made from 3D printed polymers. 3D printing offers endless flexibility in packing designs to better enhance liquid/gas contact, increase CO2 mass transfer and create more efficient absorber columns. Before exploring novel packing designs, it is necessary to identify polymer materials that can be 3D printed while also showing long-term physical and surface property stability upon exposure to corrosive amine solutions. Four polymers that are commonly used for 3D printing were evaluated for physical and surface stability during long-term exposure to a corrosive CO2-loaded amine solution at temperatures typically observed in the absorber column. Three polymers, HDPS, ABS and Nylon were found to be physically stable after 3000 hr of amine exposure at temperatures up to 60 °C. The contact angle (wetting) of the polymer surfaces were also stable after exposure to the CO2-loaded amine solution.

Multimaterial 3D printing enables a novel approach to fabrication of glass optics with tailored refractive index gradients., We demonstrate an additive manufacturing approach to produce gradient refractive index glass optics. Using direct ink writing with an active inline micromixer, we three-dimensionally print multimaterial green bodies with compositional gradients, consisting primarily of silica nanoparticles and varying concentrations of titania as the index-modifying dopant. The green bodies are then consolidated into glass and polished, resulting in optics with tailored spatial profiles of the refractive index. We show that this approach can be used to achieve a variety of conventional and unconventional optical functions in a flat glass component with no surface curvature.

MetaNetX/MNXref is a reconciliation of metabolites and biochemical reactions providing cross-links between major public biochemistry and Genome-Scale Metabolic Network (GSMN) databases. The new release brings several improvements with respect to the quality of the reconciliation, with particular attention dedicated to preserving the intrinsic properties of GSMN models. The MetaNetX website (https://www.metanetx.org/) provides access to the full database and online services. A major improvement is for mapping of user-provided GSMNs to MXNref, which now provides diagnostic messages about model content. In addition to the website and flat files, the resource can now be accessed through a SPARQL endpoint (https://rdf.metanetx.org).

Microfluidic-based microencapsulation requires significant oversight to prevent material and quality loss due to sporadic disruptions in fluid flow that routinely arise. State-of-the-art microcapsule production is laborious and relies on experts to monitor the process, e.g. through a microscope. Unnoticed defects diminish the quality of collected material and/or may cause irreversible clogging. To address these issues, we developed an automated monitoring and sorting system that operates on consumer-grade hardware in real-time. Using human-labeled microscope images acquired during typical operation, we train a convolutional neural network that assesses microencapsulation. Based on output from the machine learning algorithm, an integrated valving system collects desirable microcapsules or diverts waste material accordingly. Although the system notifies operators to make necessary adjustments to restore microencapsulation, we can extend the system to automate corrections. Since microfluidic-based production platforms customarily collect image and sensor data, machine learning can help to scale up and improve microfluidic techniques beyond microencapsulation.

A lack of predictive methodology is frequently a major bottleneck in materials development for additive manufacturing. Hence, exploration of new printable materials often relies on the serendipity ...

For widespread adoption of carbon capture and storage to fight climate change, major reductions in both the energy use and capital cost of carbon capture are needed. Many purpose-designed, water-lean solvents have recently been developed to improve the energy-efficiency of carbon capture. These solvents, including ionic liquids (ILs), have shown promise for substantially lower energy demand in post-combustion capture but have drawbacks like high viscosity and solid precipitates. Micro-encapsulation is a technique where a solvent is encased in small (∼500 μm diameter), spherical shells of a CO2-permeable polymer, greatly increasing the reactive surface area of the solvent and safely containing solid precipitates. Here, we show the kinetics of an IL are enhanced by microencapsulation. The kinetics of the IL in liquid and encapsulated form are compared with those for sodium carbonate solution and the cases where the capsule shell material limits mass transfer are identified. Finally, we make the first demonstration of microencapsulated CO2 solvents in a flow-through, fixed bed reactor. CO2 absorption rates are broadly in agreement with static CO2 absorption measurements made previously.

Direct ink writing (DIW) three-dimensional (3D) printing provides a revolutionary approach to fabricating components with gradients in material properties. Herein, we report a method for generating colloidal germania feedstock and germania-silica inks for the production of optical quality germania-silica (GeO2-SiO2) glasses by DIW, making available a new material composition for the development of multimaterial and functionally graded optical quality glasses and ceramics by additive manufacturing. Colloidal germania and silica particles are prepared by a base-catalyzed sol-gel method and converted to printable shear-thinning suspensions with desired viscoelastic properties for DIW. The volatile solvents are then evaporated, and the green bodies are calcined and sintered to produce transparent, crack-free glasses. Chemical and structural evolution of GeO2-SiO2 glasses is confirmed by nuclear magnetic resonance, X-ray diffraction, and Raman spectroscopy. UV-vis transmission and optical homogeneity measurements reveal comparable performance of the 3D printed GeO2-SiO2 glasses to glasses produced using conventional approaches and improved performance over 3D printed TiO2-SiO2 inks. Moreover, because GeO2-SiO2 inks are compatible with DIW technology, they offer exciting options for forming new materials with patterned compositions such as gradients in the refractive index that cannot be achieved with conventional manufacturing approaches.

Current microfluidic-based microencapsulation systems rely on human experts to monitor and oversee the entire process spanning hours in order to detect and rectify when defects are found. This results in high labor costs, degradation and loss of quality in the desired collected material, and damage to the physical device. We propose an automated monitoring and classification system based on deep learning techniques to train a model for image classification into four discrete states. Then we develop an actuation control system to regulate the flow of material based on the predicted states. Experimental results of the image classification model show class average recognition rate of 95.5%. In addition, simulated test runs of our valve control system verify its robustness and accuracy.

Background: To introduce a novel method for double stapling technique in colorectal anastomosis during laparoscopic anterior resection of upper rectal or sigmoid colon cancer with trans-rectal natural orifice specimen extraction (NOSE). Methods: From June 2015 and May 2016, patients with upper-rectal or sigmoid colon cancer who received treatment in Shanghai East Hospital were enrolled. Preoperative and postoperative clinical variables were analyzed and compared between groups. Postoperative pain was analyzed utilizing a visual analog scale (VAS). Postoperative overall survival was analyzed using a K-M curve. Results: A total of 99 colorectal cancer cases were randomly divided into NOSE with novel method group (NOSE, n=48) and conventional laparoscopic group (non-NOSE, n=51). No statistically significant differences in preoperative demographics of the patients as sex, age, body mass index were found among the groups. The NOSE group had the longer operation time, but less blood loss than the non-NOSE group. The NOSE group had no abdominal incision and the lower postoperative VAS score. The time for intestinal function recovery and the length of hospital stay (LOS) was statistically significantly different, with the non-NOSE group having the longer time. The incidence of postoperative complications was lower in NOSE group (5/48, 10.4%) than in the non-NOSE group (8/51, 15.7%), the difference was statistically significant. The K-M survival curve showed no statistically significant difference in the disease free survival rate between the NOSE group and non-NOSE group. Conclusion: NOSE with novel method is safe and feasible to use in patients having colorectal cancer. Compared with traditional laparoscopic surgery, the postoperative complication rates of NOSE surgery were lower with an improved short-term clinical recovery.

The capability to customize the structure or composition of an optical element gives designers access to previously unrealizable configurations that show promise for reducing costs, enhancing functionality, as well as improving the size, weight, and power of optical systems. Techniques for three-dimensional (3d) printing of glass have opened the door to novel glass optics with both unconventional structures and tailored composition. An overview of the state-of-the art in glass 3d printing will be presented. Particular emphasis will be placed on the direct ink writing (DIW) technique, in which specially formulated silica pastes are extruded through a nozzle and deposited in the geometry of interest, forming low density green bodies. The green bodies are then converted to full density, optically homogeneous glass by a series of heat treatments. The 3d printed silica-based glass components have material and optical properties that rival conventionally prepared optical grade fused silica. In addition, glass optics that contain tailored gradients in composition, such as gradient index lenses, have been achieved by DIW by blending separate inks inline at the print nozzle and directly depositing the desired composition profile before forming the glass. Strategies are also being developed to reduce time to development of new materials and structures.

We encapsulated six solvents with novel physical and chemical properties for CO

Carbon black nanoparticles (CB) were covalently modified to improve the photothermal regeneration of a CO2 capture nanofluid through decarboxylation. The photothermal release of CO2 addresses high energy costs associated with regenerating capture fluids. By incorporating sulfonamides on the surface of CB, we enhance the photothermal separation of CO2 from MEA by approximately 70% more than the unmodified CB. In contrast, with an anionic sulfonate on the surface, the total CO2 released fell by approximately 60%. We verified the chemical composition and structure of surface modification using complementary techniques including FT-IR, TGA, XPS, and Raman spectroscopy.

Three-dimensional (3d) printing has opened the door to novel glass optics with tailored composition and structure. Glass optics with custom refractive index profiles have been prepared using 3d printing, and optical performance will be discussed.

This paper describes the analysis and design of a single-phase multilevel cascaded H-bridge (CHB) converter for battery energy storage. Furthermore, it studies the second-order harmonic currents and voltages associated with single-phase converters which are transferred from the ac power side to the dc side. The conventional strategy used to reduce ripple current involves bulky dc-link capacitors connected in parallel with the dc bus for ripple reduction. An active filtering strategy is proposed to minimize the energy storage requirements.

Dermatophytes are the most common agents of superficial mycoses in humans and animals. The aim of the present investigation was to systematically identify the extracellular possibly secreted proteins that are putative virulence factors and antigenic molecules of dermatophytes. A complete gene expression profile of Arthroderma benhamiae was obtained during infection of its natural host (guinea pig) using RNA seq technology. This profile was completed with those of the fungus cultivated in vitro in two media containing keratin and soy meal protein as the sole source of nitrogen and in Sabouraud medium. More than 60 of transcripts deduced from RNA seq data differ from those previously deposited for A. benhamiae. Using these RNA seq data along with an automatic gene annotation procedure followed by manual curation we produced a new annotation of the A. benhamiae genome. This annotation comprised 7405 CDSs among which only 2662 were identical to the currently available annotation 383 were newly identified and 15 secreted proteins were manually corrected. The expression profile of genes encoding proteins with a signal peptide in infected guinea pigs was found very different from that during in vitro growth when using keratin as substrate. Especially the sets of the 12 most highly expressed genes encoding proteases with a signal sequence only had the putative vacuolar aspartic protease gene PEP2 in common during infection and in keratin medium. The most upregulated gene encoding a secreted protease during infection was that encoding subtilisin SUB6 which is a known major allergen in the related dermatophyte Trichophyton rubrum. IMPORTANCE Dermatophytoses (ringworm jock itch athlete’s foot and nail infections) are the most common fungal infections but their virulence mechanisms are poorly understood. Combining transcriptomic data obtained from growth in various culture conditions with data obtained during infection led to a significantly improved genome annotation. About 65 of the protein coding genes predicted with our protocol did not match the existing annotation for A. benhamiae. Comparing gene expression during infection on guinea pigs versus keratin degradation in vitro which is supposed to mimic the host environment revealed the critical importance of using real in vivo conditions for investigating virulence mechanisms. The analysis of genes expressed in vivo encoding cell surface and secreted proteins particularly proteases led to the identification of new allergen and virulence factor candidates.

Microstructure is a critical element of many synthetic materials including materials for separations, heat transfer, and electrical energy storage. Similarly, natural systems employ microstructure for most structural and mass transfer processes. These systems achieve high-levels of performance through continuous, structural remodeling, which enables adaptation and improvement of their raw materials. In contrast, current microfabrication techniques produce static materials that do not adapt. Here, we show a fabrication process inspired by biological systems capable of adaptation. Combining the basic elements of morphogenesis, reaction and diffusion (RD), and a microvascular scaffold, we pattern microstructured materials by balancing the rates of depolymerization and inhibition of that depolymerization with a diffusive agent. As a result, the materials continuously reshape their microstructure and improve their performance. Using this system, we also recapitulate a hallmark of biological structures, formati...

We analyse the nonlinear behaviour of a third-order class-D amplifier, and demonstrate the remarkable effectiveness of the recently introduced ripple compensation (RC) technique in reducing the audio distortion of the device. The amplifier converts an input audio signal to a high-frequency train of rectangular pulses, whose widths are modulated according to the input signal (pulse-width modulation) and employs negative feedback. After determining the steady-state operating point for constant input and calculating its stability, we derive a small-signal model (SSM), which yields in closed form the transfer function relating (infinitesimal) input and output disturbances. This SSM shows how the RC technique is able to linearise the small-signal response of the device. We extend this SSM through a fully nonlinear perturbation calculation of the dynamics of the amplifier, based on the disparity in time scales between the pulse train and the audio signal. We obtain the nonlinear response of the amplifier to a general audio signal, avoiding the linearisation inherent in the SSM; we thereby more precisely quantify the reduction in distortion achieved through RC. Finally, simulations corroborate our theoretical predictions and illustrate the dramatic deterioration in performance that occurs when the amplifier is operated in an unstable regime. The perturbation calculation is rather general, and may be adapted to quantify the way in which other nonlinear negative-feedback pulse-modulated devices track a time-varying input signal that slowly modulates the system parameters., Comment: 30 pages, 6 figures

Motivation Genome-scale metabolic networks and transcriptomic data represent complementary sources of knowledge about an organism’s metabolism, yet their integration to achieve biological insight remains challenging. Results We investigate here condition-specific series of metabolic sub-networks constructed by successively removing genes from a comprehensive network. The optimal order of gene removal is deduced from transcriptomic data. The sub-networks are evaluated via a fitness function, which estimates their degree of alteration. We then consider how a gene set, i.e. a group of genes contributing to a common biological function, is depleted in different series of sub-networks to detect the difference between experimental conditions. The method, named metaboGSE, is validated on public data for Yarrowia lipolytica and mouse. It is shown to produce GO terms of higher specificity compared to popular gene set enrichment methods like GSEA or topGO. Availability and implementation The metaboGSE R package is available at https://CRAN.R-project.org/package=metaboGSE. Supplementary information Supplementary data are available at Bioinformatics online.

Candida glabrata is an important fungal pathogen which develops rapid antifungal resistance in treated patients. It is known that azole treatments lead to antifungal resistance in this fungal species and that multidrug efflux transporters are involved in this process. Specific mutations in the transcriptional regulator PDR1 result in upregulation of the transporters. In addition, we showed that the PDR1 mutations can contribute to enhance virulence in animal models. In this study, we were interested to compare genomes of two specific C. glabrata-related isolates, one of which was azole susceptible (DSY562) while the other was azole resistant (DSY565). DSY565 contained a PDR1 mutation (L280F) and was isolated after a time-lapse of 50 d of azole therapy. We expected that genome comparisons between both isolates could reveal additional mutations reflecting host adaptation or even additional resistance mechanisms. The PacBio technology used here yielded 14 major contigs (sizes 0.18–1.6 Mb) and mitochondrial genomes from both DSY562 and DSY565 isolates that were highly similar to each other. Comparisons of the clinical genomes with the published CBS138 genome indicated important genome rearrangements, but not between the clinical strains. Among the unique features, several retrotransposons were identified in the genomes of the investigated clinical isolates. DSY562 and DSY565 each contained a large set of adhesin-like genes (101 and 107, respectively), which exceed by far the number of reported adhesins (63) in the CBS138 genome. Comparison between DSY562 and DSY565 yielded 17 nonsynonymous SNPs (among which the was the expected PDR1 mutation) as well as small size indels in coding regions (11) but mainly in adhesin-like genes. The genomes contained a DNA mismatch repair allele of MSH2 known to be involved in the so-called hyper-mutator phenotype of this yeast species and the number of accumulated mutations between both clinical isolates is consistent with the presence of a MSH2 defect. In conclusion, this study is the first to compare genomes of C. glabrata sequential clinical isolates using the PacBio technology as an approach. The genomes of these isolates taken in the same patient at two different time points exhibited limited variations, even if submitted to the host pressure.

The secondary structure of an RNA molecule represents the base-pairing interactions within the molecule and fundamentally determines its overall structure. In this chapter, we overview the main approaches and existing tools for predicting RNA secondary structures, as well as methods for identifying noncoding RNAs from genomic sequences or RNA sequencing data. We then focus on the identification of a well-known class of small noncoding RNAs, namely microRNAs, which play very important roles in many biological processes through regulating post-transcriptionally the expression of genes and which dysregulation has been shown to be involved in several human diseases.

Objective: The aim of this study was to assess the initial experience of transcutaneous aortic valve implantation (TAVI) in a high risk aortic stenosis population not suitable for conventional surgical valve replacement. Background: No data exist for TAVI with Medtronic CoreValve in South Africa and especially not in a public private partnership hospital complex. Methods: Retrospective data regarding severe aortic stenosis evaluation, risk stratifi cation and management were evaluated over a 24 month period. Results: A total of 106 patients were evaluated of whom 17 were accepted for surgical valve replacement (SVR) while TAVI was attempted in 25. The CoreValve was successfully implanted in 96% (24/25) of the cases. No procedural or peri-procedural deaths occurred. Three patients required permanent pacemaker insertion in the peri-procedural period and 2 patients had vascular access complications requiring blood transfusion only. Median hospital stay was 3.7days (range: 2 - 7). Aortic valve gradient showed a signifi cant reduction after valve implantation, which was sustained during follow-up (p

Natural systems employ microvascular exchangers with circular packing for both heat and mass transfer that closely conform to the compact, packing of circles of two diameter. Mathematical descriptions of these systems exist, but have rarely been studied in three dimensions for their exchange properties. We focus on four close packed patterns: “Hexagonal” “Dodecagonal”, “Squarer”, and “Double Squarer”. While two of these patterns have natural analogs, the others are abiological. We compare computationally and experimentally the mass and heat transfer characteristics of these various patterns. Intriguingly the “Double Squarer” pattern, had the highest transfer rates within our fabrication constraints.

This article investigates the positive effects on rents by office clustering in Ho Chi Minh City. The density of buildings in the CBD increases labor productivity and creates added value for the whole economy, stimulating economic growth and development. Applying similar methodologies and approaches used to identify the clustering effects in Houston and Amsterdam, I separated the rent effects of location density. After controlling main characteristics of buildings including: the location, age, size, quality and operational status, I find a strong positive effect of being located in dense office areas. For every time the size of the office district doubles, the rents tenants are willing to pay increases by 4.3 to 7.1 percent. This finding extends the literature of the clustering effects from the developed world to the developing one. In other words, the results support the argument that real estate market behavior is remarkably similar from place to place.

Lowering the parasitic energy demand of CO2 capture technologies is a basic and technical challenge. Using alternative energy sources could reduce energy costs both by lowering the energy required for regeneration and by replacing parasitic energy with renewable sources. Here we report the use of actinic light for the photo-thermal regeneration of CO2 from capture solutions containing nanoparticles. We demonstrate an enhanced regeneration of CO2 due to addition of carbon black nanoparticles. CO2 regeneration efficiencies increased with higher nanoparticle concentrations and higher initial solution temperatures.

Coffee-powered chemistry: Low-grade waste heat on surfaces can be used to drive chemical reactions, including the regeneration of a CO2 capture solution. Flowing two-phase heat transfer has been implemented within microvascular systems. This stripping system can be adapted to pre-fabricated surfaces, as demonstrated by a coffee mug containing a 1.2 m long microchannel. MEA=monoethanolamine.

Climate change is an additional challenge for the African continent, which is already facing many challenges. It increases the uncertainty regarding the probability of flood occurrence, making weather less predictable, rainfall more uncertain but heavy storms more likely. This necessitates rethinking and changing the traditional ways of planning and dealing with floods. When flooding occurs according to a predictable pattern, an optimal package of flood damage control measures can be planned in advance, but when flood events become unpredictable due to climate change, the optimal package of flood damage control measures will change, cannot be planned with sufficient certainty in advance and different management strategies are needed. In this study a benefit cost analysis was applied to compare the merits of different structural flood mitigation options for Soweto-on-Sea, with and without climate change. The option with the highest net benefit remains the clearing out of the river channel for both...

Here we report the investigation of controlled PbI2 secondary phase formation in CH3NH3PbI3 (MAPI) photovoltaics through post-deposition thermal annealing, highlighting the beneficial role of PbI2 on device performance. Using high-resolution transmission electron microscopy we show the location of PbI2 within the active layer and propose a nucleation and growth mechanism. We discover that during the annealing that PbI2 forms mainly in the grain boundary regions of the MAPI films and that at certain temperatures the PbI2 formed can be highly beneficial to device performance – reducing current–voltage hysteresis and increasing the power conversion efficiency. Our analysis shows that the MAPI grain boundaries as susceptible areas that, under thermal loading, initiate the conversion of MAPI into PbI2.

Purpose-designed, water-lean solvents have been developed to improve the energy efficiency of CO2 capture from power plants, including CO2-binding organic liquids (CO2BOLs) and ionic liquids (ILs). Many of these solvents are highly viscous or change phases, posing challenges for conventional process equipment. Such problems can be overcome by encapsulation. Micro-Encapsulated CO2 Sorbents (MECS) consist of a CO2-absorbing solvent or slurry encased in spherical, CO2-permeable polymer shells. The resulting capsules have diameters in the range of 100–600 μm, greatly increasing the surface area and CO2 absorption rate of the encapsulated solvent. Encapsulating these new solvents requires careful selection of shell materials and fabrication techniques. We find several common classes of polymers are not compatible with MECS production, but we develop two custom formulations, a silicone and an acrylate, that show promise for encapsulating water-lean solvents. We make the first demonstration of an encapsulated IL for CO2 capture. The rate of CO2 absorption is enhanced by a factor of 3.5 compared to a liquid film, a value that can be improved by further development of shell materials and fabrication techniques.

The purpose of this letter is to stress once more the importance of a reliable ambulance service to and from rural district hospitals in South Africa, along roads that are usable . The rural hospital cannot play its role as ‘hub’ without a connecting transport lifeline. The attitudes of some staff members at some district hospitals have to be addressed. Proper training (and re-training) in the basic tenets of the ethos of healthcare are a top priority.

PurposeThe flying capacitor converter (FFC) balances the clamping capacitor voltages naturally when phase shifted carrier modulation is used. Several models that describe this mechanism, and to estimate the time constants following a perturbation, are discussed in the literature. However, due to the model complexity, numerical methods must be used to evaluate these models. This paper aims to present a closed form expression, using a reference table, that describes a maximum bound for the voltage balancing time constant.Design/methodology/approachThe FCC is analysed in the frequency domain. A decomposition of the characteristic matrix that describes the voltage balancing mechanism is used. The resulting real symmetric matrix is factorised by using approximations of the load characteristics at the frequencies of interest.FindingsThe minimum eigenvalue of the factorised matrix is used to determine a maximum bound for the time constant of the voltage balancing. Since the factorised matrix is independent of variations in switching frequency and load, the eigenvalue of interest can be calculated once and tabulated.Originality/valueThe closed form expression can be used for quick calculations of the maximum time constant under different operating conditions. Furthermore, the expression provides considerable insight into the influences circuit design choices have on the balancing mechanism.