bluuebunny/crossref_metadata_2025 huggingface dataset:
Chronology and sequence of deciduous teeth eruption in children with microcephaly associated to the Zika virus
Authors: D'Agostino Érica Santana , Chagas Janeusa Rita Leite Primo , Cangussu Maria Cristina Teixeira , Vianna Maria Isabel Pereira
Published: December 2019

Introduction

Deciduous teeth eruption is connected to children's growth and development. In Brazil, with the increase in the occurrence of children born with microcephaly associated to exposure to Zika virus, studies about orofacial alterations were necessary.

Objective

Describe the chronology and sequence of deciduous teeth in children with microcephaly due to the fetal exposure to Zika virus.

Methodology

A cross‐sectional study involving 74 children of a neuropediatric reference unit in Salvador, Bahia, in 2017 was conducted. Through use of secondary data, interviews with mothers and children's exam, the population was characterized, the chronology and sequence of deciduous teeth eruption was registered, and the analysis of the variables was proceeded.

Results

The first eruption happened between 4 and 17 months of age and 52.70% had a delay in the eruption of incisors. The average eruption time for the maxilla varies from 17.92 (16.56‐19.28; 95% CI) to 20.43 (19.35‐21.51; 95% CI) months, and the jaw from 11.57 (6.85‐18.99; 95% CI) to 20.20 (19.09‐21.31; 95% CI) months. In 77.94% of population, the eruption of the first teeth was in the lower arch and in 33.82%, molars and/or canines erupted before the incisors.

Conclusions

There were alteration in the chronology and sequence of deciduous teeth eruption.
Optical coherence tomographic (OCT) evaluation of intraoral non‐ablative erbium: YAG laser (SMOOTH mode) in rejuvenation of nasolabial folds; A prospective randomized split face comparative pilot study
Authors: Moftah Nayera , Samy Nevien , Allam Riham S. H. M. , El Tagy Shaza A. H. , Abdelghani Rania
Published: December 2019

Background

There are both few non‐comparative studies investigating the efficacy of intraoral Er: YAG laser (SMOOTH mode) in rejuvenating nasolabial folds (NLFs) and lack of valid and objective wrinkles scales. In this prospective randomized split face comparative pilot study, we investigated the safety and efficacy of intraoral Er: YAG laser (SMOOTH MODE) compared with extraoral approach in rejuvenating NLFs using OCT as an objective evaluating tool.

Materials and Methods

Twenty adult women with notable NLFs were randomized in this study. The patients received 5 monthly sessions of Er: YAG laser (SMOOTH mode) using intraoral approach on one side and extraoral approach on the other side. Outcome was evaluated 2 weeks and 4 months post‐treatment by Global Aesthetic Improvement Scale (GAIS), OCT, and patients’ satisfaction. Side effects were also evaluated.

Results

Intraoral sides had significant increase in OCT evaluated dermal thickness at 4 months post‐treatment (P = .03) without side effects compared with extraoral sides. Extraoral approach had significantly higher patients’ satisfaction compared with intraoral approach at 2 weeks and 4 months post‐treatment (P = .03, .02, respectively). Insignificant differences between both approaches were found regarding GAIS scoring, OCT evaluated epidermal thickness at 2 weeks and 4 months post‐treatment, and OCT evaluated dermal thickness at 2 weeks post‐treatment (P < .05).

Conclusion

Intraoral Er: YAG laser (SMOOTH mode) is safer and more effective than extraoral approach in rejuvenating NLFs. OCT is a promising objective tool for evaluating facial wrinkles. Further studies are still needed.
Mantle resistance against Gibraltar slab dragging as a key cause of the Messinian Salinity Crisis
Authors: Capella Walter , Spakman Wim , van Hinsbergen Douwe J. J. , Chertova Mariya V. , Krijgsman Wout
Published: December 2019

The Messinian Salinity Crisis (5.97–5.33 Ma) was caused by the closure of the Atlantic‐Mediterranean gateways that cut through the Gibraltar orogenic system. The geodynamic drivers underlying gateway closure and re‐opening are still debated. Here, we interrogate the gateway successions to find the imprints of surface deformation, infer the timing and nature of associated geodynamic drivers, and test such inferences against numerical simulations of slab dynamics. We find that since the latest Miocene, a tectonic framework was established in the gateway region dominated simultaneously by (a) relative plate convergence, (b) slab tearing under the eastern Betic Cordillera and (c) mantle resistance against north‐northeastward dragging of the Gibraltar slab by the African plate's absolute motion. We propose that mantle‐resisted slab dragging and slab tearing operated in concert closing the gateways that caused the Messinian Salinity Crisis, whereas sinking of heavy oceanic lithosphere located between buoyant continental plates re‐opened the Strait of Gibraltar at 5.33 Ma.
Exploring the proteome associated with the mRNA encoding the D1 reaction center protein of Photosystem II in plant chloroplasts
Authors: Watkins Kenneth P. , Williams‐Carrier Rosalind , Chotewutmontri Prakitchai , Friso Giulia , Teubner Marlene , Belcher Susan , Ruwe Hannes , Schmitz‐Linneweber Christian , van Wijk Klaas J. , Barkan Alice
Published: December 2019

Synthesis of the D1 reaction center protein of Photosystem II is dynamically regulated in response to environmental and developmental cues. In chloroplasts, much of this regulation occurs at the post‐transcriptional level, but the proteins responsible are largely unknown. To discover proteins that impact psbA expression, we identified proteins that associate with maize psbA mRNA by: (i) formaldehyde cross‐linking of leaf tissue followed by antisense oligonucleotide affinity capture of psbA mRNA; and (ii) co‐immunoprecipitation with HCF173, a psbA translational activator that is known to bind psbA mRNA. The S1 domain protein SRRP1 and two RNA Recognition Motif (RRM) domain proteins, CP33C and CP33B, were enriched with both approaches. Orthologous proteins were also among the enriched protein set in a previous study in Arabidopsis that employed a designer RNA‐binding protein as a psbA RNA affinity tag. We show here that CP33B is bound to psbA mRNA in vivo, as was shown previously for CP33C and SRRP1. Immunoblot, pulse labeling, and ribosome profiling analyses of mutants lacking CP33B and/or CP33C detected some decreases in D1 protein levels under some conditions, but no change in psbA RNA abundance or translation. However, analogous experiments showed that SRRP1 represses psbA ribosome association in the dark, represses ycf1 ribosome association, and promotes accumulation of ndhC mRNA. As SRRP1 is known to harbor RNA chaperone activity, we postulate that SRRP1 mediates these effects by modulating RNA structures. The uncharacterized proteins that emerged from our analyses provide a resource for the discovery of proteins that impact the expression of psbA and other chloroplast genes.
A conceptual framework of patient‐reported outcomes in people with venous leg ulcers
Authors: Ruseckaite Rasa , Richards Catelyn , Rutherford Claudia , Team Victoria , Turnour Louise , Franks Peter , Weller Carolina
Published: December 2019

Venous leg ulcers (VLUs) are a common chronic often undertreated condition, which affects individual's health‐related quality of life (HRQoL). Numerous patient‐reported outcome measures (PROMs) have been validated to capture HRQoL in patients with VLUs. However, available instruments contain many items, are hard to use in clinical practice, and present with weak responsiveness. This study aims to determine clinical utility of an existing VLU‐QoL instrument and to develop a comprehensive PROs assessment framework to guide clinical practice treatment in people with VLUs in Australia. Semi‐structured qualitative interviews were conducted with VLU patients (N = 13) and their managing clinicians (N = 6) in Victoria, Australia. Interview topics covered content and face validity, appropriateness, and acceptability of the VLU‐QoL instrument to determine suitable and appropriate for use in clinical practice. Clinicians and patients agreed that a VLU‐QoL instrument was needed in clinical practice. Both clinicians and patients agreed it would be appropriate to answer PROMs questions prior to consultation with clinicians every 3–6 months. However, patients considered that some of the questions are ambiguous and too technical. Patients reported that it would be useful to include additional items relating to daily wound care, compression bandaging, and dressings. Clinicians reported that the VLU‐QoL instrument was too long and required restructuring to facilitate utility in practice. A conceptual framework for HRQoL in VLUs included traditional HRQoL components and VLU‐specific issues. Overall, the VLU‐QoL was well accepted, although changes to make it more concise, comprehensive, and to clearly reflect consumers' perspectives were lacking. The proposed conceptual framework will inform the development of a new PROM for use by clinicians and patients in clinical settings.
Mixing Efficiency Comparison of Symmetric and Asymmetric Airfoil Blades in a Continuous Stirred Tank Reactor
Authors: Woradej Manosroi , Jirayu Thongsanitkarn , Parinya Ruangsak
Published: December 2019

This study compared mixing efficiencies of the symmetric and asymmetric airfoil blades in a continuous stirred tank reactor (CSTR) at various mixing velocities and angles of attack. The symmetric airfoil blades (NACA0009 and NACA0015) and asymmetric airfoil blades (NACA2414 and NACA4412) were set at different angles of attack and mixing velocities. The tank reactor was equipped with two sets of three airfoil blades at the upper and the lower parts of the stirring shafts at the angles of attack 0 deg, 10 deg, 16 deg, and 20 deg, and the mixing velocities of 80, 110, 140, and 190 rpm. The mixing efficiencies were evaluated from the homogenous appearance of plastic particles (5 mm in diameter) dispersed in water by an image processing technique. The results indicated that the mixing efficiencies of both the symmetric and asymmetric airfoil blades increased with increasing mixing velocities and at the angles of attack 0 deg and 10 deg, and slightly decreased with increasing mixing velocities at the angles of attack 16 deg and 20 deg due to the blade stall and mixing saturation as well as short-circuiting flow from the high flowrate. There was no significant mixing velocity effect on mixing efficiencies at the angles of attack 10 deg, 16 deg, and 20 deg except 0 deg of the symmetric and asymmetric airfoil blade systems. The two asymmetric airfoil blade types gave higher mixing efficiencies than the two symmetric airfoil blade types. The results from this study can be applied for a novel blade design for an efficient mixing flow, which will be beneficial for industrial biogas production.
Development and Test of a Direct Contact Heat Exchanger (Particle - Air) for Industrial Process Heat Applications
Authors: Hertel Johannes , Ebert Miriam , Amsbeck Lars , Gobereit Birgit , Rheinländer Jens , Hirt Alexander , Frantz Cathy
Published: December 2019

A direct absorption receiver using ceramic particles (CentRec) has been successfully developed by DLR and tested under solar conditions at the Juelich Solar Power Tower, demonstrating receiver outlet temperatures of more than 900 °C. The next step towards commercial application of the technology is to demonstrate a cost-effective, high temperature heat extraction and transfer to a process medium. Besides e.g. steam for electricity generation in a steam turbine, hot air can be used to supply heat to industrial processes with energy demand at high temperature level.

A great potential for higher efficiencies and lower costs has been identified for a moving bed heat exchanger. Several concepts of direct contact heat exchangers have been analyzed and evaluated. The selected concept is a combination of several crossflow-sections that are arranged in series with fluid-mixing-chambers between each crossflow-section.

Based on the selected design a heat exchanger prototype with 10 kW thermal power and a design air outlet temperature of 750 °C has been built and integrated into a test setup.

The test setup provides particles at 900 °C that are heated up electrically inside a hopper on top of the heat exchanger. Hot particles are then moving downwards (moving bed) from the hopper through the direct contact heat exchanger driven by gravity. Cold air supplied by a compressor flows through the particle bed in cross-flow and is heated up. The hot air flow leaves the heat exchanger with a temperature of 750 °C. The particle mass flow is controlled by an oscillating mass flow controller, positioned under the heat exchanger. The cold particles are collected in a container on the bottom. The particle cycle is closed by transporting them back to the hopper. A measurement and control system is implemented to carry out the tests.

The test setup has undergone successful commissioning in October and an extensive testing phase started in January 2019.

This paper presents the development and manufacturing as well as the successful commissioning of the heat exchanger prototype.
Heat Current Method Based Modeling and Optimization of a Solar-Driven Absorption Chiller for Residential Houses
Authors: Chen Qun , Zhao Tian
Published: December 2019

The utilization of solar energy is attracting rapidly increasing researches due to its many advantages, and an important application is to satisfy the refrigeration demand of residents with the solar-assisted absorption chillers. However, the simple solar-assisted refrigeration system cannot always meet the cooling demand of residents due to the mismatch between solar power and the refrigeration load. Therefore, the thermal energy storage device is introduced into the solar-assisted system to increase the stability of the refrigeration system and reduce the waste of solar energy. In this contribution, a solar-assisted absorption chiller system together with the TES device is presented and optimized to minimize the operation cost of the system. The system is modeled using the newly proposed heat current method and its global constraints are constructed, which largely reduces the number of the constraints comparing to the traditional equation-oriented approach. Optimization results present that the optimized design of the system reduces the total operation cost effectively.
Effects of Baffle Width on Heat Transfer to an Immersed Coil Heat Exchanger: Experimental Optimization
Authors: Nicodemus Julia Haltiwanger , Huang Xiaoqi , Dentinger Emily , Petitt Kyle , Smith Joshua H.
Published: December 2019

In this work, we investigate the effects of the width of an annular baffle region on natural convection heat transfer to an immersed, coiled heat exchanger in an otherwise quiescent sensible hot water storage tank. In experiments, the coiled heat exchanger sits in an annular region created by the tank wall and a straight, cylindrical baffle. The width of this baffle region is 1.5, 2, 3, or 4 times the heat exchanger diameter, These experiments are compared to each other and to corresponding control experiments with no baffle. In general, all baffles create considerable benefits over their respective control experiments, consistent with past studies. The considered metrics of heat transfer rate, fraction of energy discharged from the tank, and heat exchanger outlet temperature show that heat transfer is improved slightly by narrowing the baffle region. For example, relative to their respective controls, the energy extracted from the tank after 30 min of discharge in the 1.5D, 2D, 3D and 4D experiments is 23.2%, 20.8%, 18.1%, and 14.7% higher, respectively. This improvement in natural convection heat transfer as the baffle region narrows is attributed to the increasing thermal stratification observed in experiments with increasingly narrow baffle regions.
Renewable Hydrogen Production via Thermochemical/Electrochemical Coupling
Authors: Babiniec Sean M. , Ambrosini Andrea , Miller James E.
Published: December 2019

A coupled thermochemical/electrochemical cycle was investigated to produce hydrogen from renewable resources. Like a conventional thermochemical cycle, this approach leverages chemical energy stored in a thermochemical working material that is reduced thermally by solar energy. However, in this concept, the stored chemical energy provides only a fraction of the energy required for effectively splitting steam to produce hydrogen. To push the reaction towards completion, an electrically-assisted proton-conducting membrane is employed to separate and recover hydrogen as it is produced. This novel coupled-cycle concept provides several benefits. First, the required oxidation enthalpy of the reversible thermochemical material is decreased, enabling the process to occur at lower temperatures. Second, removing the requirement for spontaneous steam splitting widens the scope of materials compositions, allowing for less expensive/more abundant elements to be used. Lastly, thermodynamics calculations suggest that this concept can potentially reach higher efficiencies than photovoltaic-to-electrolysis hydrogen production. A novel thermochemical/electrochemical test stand was conceptualized and constructed to prove the concept, and the practical feasibility of the proposed coupled cycle was assessed by validating the individual components of the system: proton conduction across a BaCe0.1Zr0.8Y0.1O3-δ (BCZY18) membrane, thermochemical activity of the CaAl0.2Mn0.8O3−δ (CAM28) working material reduced at 650 °C, and indirect observation of hydrogen production.
The Influence of Structure on the Electrochemical and Thermal Response of Li-Ion Battery Electrodes
Authors: Patel Prehit , Nelson George J.
Published: December 2019

The continued advancement of lithium ion batteries for transportation applications requires addressing two key challenges: increasing energy density and providing fast charging capabilities. The first of these challenges can be met in part through the use of thicker electrodes, which reduce the electrochemically inactive mass of the cell. However, implementation of thick electrodes inherently presents a trade-off with respect to fast charging capabilities. As thickness is increased, transport limitations exert greater influence on battery performance and reduce the ability of the battery to meet aggressive charge conditions. This trade-off can manifest over multiple length scales. At the particle-scale, interactions between solid diffusion and reaction kinetics influence the effective storage of lithium within the active material. At the electrode scale, diffusion limitations can lead to local variations in salt concentrations and electric potential. These short-range and long-range effects can combine to influence local current and heat generation. In the present work, a pseudo-2D lithium ion battery model is applied to understand how active material particle size, porosity, and electrode thickness impact local field variables, current, heat generation, and cell capacity within a single cell stack. COMSOL Multiphysics 5.2 is used to implement the pseudo-2D model of a lithium ion battery consisting of a graphite negative electrode, polymer separator, and lithium transition metal oxide positive electrode. Lithium hexafluorophosphate (LiPF6) in 1:1 ethylene carbonate (EC) and diethylene carbonate (DEC) was used as the electrolyte. The model was built assuming that the active particles are representative spherical particles. The governing equations and boundary conditions were set following the common Newman model. Cell response under varied combinations of charge and discharge cycling is assessed for rates of 1C and 5C. Aggressive charge and discharge conditions lead to locally elevated C-rates and attendant increases in local heat generation. These variations can be impacted in part by tailoring electrode structures. To this end, results for parametric studies of active material particle size, porosity, and electrode thickness are presented and discussed.
Two Parameter J-A Estimation for Weld Centerline Cracks in Welded Single-Edge Cracked Plate Under Tensile Loading
Authors: Duan Chuanjie , Zhang Shuhua
Published: December 2019

This work examines the J–A two-parameter characterization of elastic–plastic crack front fields for weld centerline cracks under tensile loading. Extensive finite element analyses (FEA) have been conducted to obtain solutions of constraint parameter A, which is the second parameter in a three-term elastic-plastic asymptotic expansion for the stress field near the tip of mode-I crack, for modified boundary layer (MBL) model and welded single-edge cracked plate (SECP). Solutions of the constraint parameter A were obtained for the material following the Ramberg-Osgood power law. The crack geometries analyzed include shallow and deep cracks, and remote tension loading levels cover from small-scale to large-scale yielding conditions. The effects of weld material mismatch and weld width on crack tip constraint were considered in the FEA. A constraint parameter AM, only caused by material strength mismatch, is defined and its parametric equation was obtained. The total constraint in the bi-material weldment can be predicted by adding together AM and A in the homogeneous material. Good agreements were achieved for welded SECP specimen with different crack size and weld width from small-scale to large-scale yielding conditions. This methodology would be useful for performing constraint-based elastic-plastic fracture analyses of other welded test specimens.
Wave Impact Load and Corresponding Nonlinear Response of a Semi-Submersible
Authors: Guo Yinghao , Xiao Longfei , Wei Handi , Li Lei , Deng Yanfei
Published: December 2019

Offshore platforms operating in harsh ocean environments often suffer from severe wave impacts which threaten the structural integrity and staffs safety. An experimental study was carried out to investigate the wave impact load and its effect on the global response of a semi-submersible. First, two typical wave impact events occurring successively in the wave test run are analyzed, including the characteristics of incident waves, relative wave elevations and the spatial distribution of the wave impact load. Subsequently, the corresponding global response of the semi-submersible under these two wave impacts are investigated in time domain. It reveals that compared with the incident wave, the relative wave elevation has a more straightforward relationship with the wave impact load. The relative wave crest height is associated with the spatial distribution of the wave impact load, while the local wave steepness matters more in the magnitude of the wave impact load. The impulsive effect of the wave impact load on the motion behaviors is not obvious. But severe wave impacts can introduce excessive horizontal accelerations and nonlinear behaviors like ringing in the acceleration response.
Effects of Tubercles on Blade and Wake of HAMCT in Post Stall Regimes: Linear Cascade Study
Authors: Dondapati Varun Raj , Kantharaj Murali
Published: December 2019

The aim of the current work is to find out the effects of tubercles on the blade and wake of the turbine, which could be used in situations, where interaction among the array turbines is inevitable. Steady simulations are performed on a linear cascade setup of modified and unmodified infinite span NACA 63421 section blade, at Reynolds numbers 5 × 105 and 106 at inboard (low radial location) spacing. The tubercles used are at the scale of the boundary layer. The study showed that the boundary layer scale tubercles are advantageous only at higher Re and deeper stall regimes.
On the Use of Computational Fluid Dynamics (CFD) to Assess the Impact of Low-Load Operations on Heat Recovery Steam Generator (HRSG) Tube Module Integrity
Authors: Fabricius Andreas , Moelling David S. , Rusaas Jan
Published: December 2019

As the electricity market has evolved with the addition of renewables to the generation mix, Heat Recovery Steam Generators (HRSGs) that were originally designed for base load conditions are now frequently forced to operate in a cycling and/or low-load regime. This can lead to front end tube-to header fatigue, creep or creep-fatigue failures, often induced by Gas Turbine (GT) flow imbalances causing locally-elevated tube temperatures and/or bending stresses on joints due to large temperature differences between tube rows. This paper focuses on the use of Computational Fluid Dynamics (CFD) as a tool to analyze the risks of shifting operation mode. Exhaust gas flow profiles were analyzed for various low load conditions in two power plants with differing vertical designs. One of the plants had already moved into cycling mode and suffered tube failures that were directly related to low-load (and start-up) exhaust flow patterns, the other plant is projected to operate in a frequent cycling mode in the near future. The contribution of CFD to identifying the conditions that lead to failure for the first plant is presented, along with projections on the potential impact of lowload operation on the second plant design in terms of risk of hotend tube failures. Mechanisms to reduce the failure risk, such as addition of flow-conditioning devices, are also investigated.
Optimization of Engine Performance and Emission for Various n-Butanol Blends at Different Operating Parameter Condition Using MADM Technique
Authors: Patil Amit R. , Desai Avinash D.
Published: December 2019

In present work, optimization of engine performance and emission were performed for different butanol diesel blends (5–20%) for various engine operating parameter using Taguchi DoE with AHP Optimization Technique. Single cylinder VCR Engine (CI) was fueled with different blend of diesel and butanol and tested for various CR, FIP and FIT at different load conditions (Idle, 1/3, 2/3 and full load). First 3-D interaction plot is drawn to understand the effect of different engine parameter on butanol-diesel blend combustion at different load conditions for NOx and Smoke formation. It’s observed that result vary with changes in operating parameter with different load conditions. Hence to optimize the engine operating parameter setting for correct butanol blend for all load conditions, AHP optimization with Taguchi DoE is performed and it’s found that butanol blend of 15% with CR of 15, FIP of 260bar and FIT of 25°bTDC is optimum combination to get lowest emission with good engine performance. The use of 15% butanol is found most suitable as it gives favorable engine performance and low emission for all test load conditions.
Multilevel Optimal Design of a Solar PV Array System Using Game Theory Approach
Authors: Lee Hoe-Gil
Published: December 2019

This study proposes a method, grounded in a multilevel decision-making approach, for a stationary fixed-plate photovoltaic (PV) collector system. The system is comprised of three different subsystems: cell, panel, and array. We consider photovoltaic effects for output performance and an inverter system for distribution from the PV collector, including multiple conflicting objectives in individual subsystems in terms of cell conversion efficiency, power output, incident solar energy, seasonal characteristics, and costs. In terms of the performance in individual subsystems, the problem is reformulated into several smaller subproblems at each subsystem, and a coordination problem at the system level is compromised for optimization purposes. Multilevel optimization for the stationary fixed-plate PV collector system is achieved through the results of single-objective optimization that uses Genetic Algorithm programming (GA) to find global optimum solutions with decision-making under modified game theory. Thus, this work contributes to the optimal design of a stationary fixed-plate PV collector system for the best compromise solution based on specified requirements.
A Flame-Assisted Fuel Cell (FFC) System With Self-Sustained Micro-Combustion at High Equivalence Ratios
Authors: Tian Jiashen , Milcarek Ryan J.
Published: December 2019

Flame-assisted fuel cell (FFC) systems have been investigated and developed for small scale power generation applications. The introduction of micro-combustion into the FFC setup has potential to increase the electrical efficiency of the system and reduce the size. However, micro-combustion at high equivalence ratios in FFC systems still needs more investigation. In this paper, a FFC system with micro-combustion at high equivalence ratios is discussed. The thermal and mass balance in this system are analyzed to evaluate the theoretical possibility of self-sustained micro-combustion at high equivalence ratios in FFC systems. The effect of heat recirculation on the system performance is investigated. Due to operation at high equivalence ratios, the electrical efficiency of the system is competitive with other micro-scale power generation systems and also shows great potential for high performance micro combined heat and power (CHP) systems.
Hydrogen Enrichment Effects in Gaseous Fuels on Distributed Combustion
Authors: Karyeyen Serhat , Feser Joseph S. , Gupta Ashwani K.
Published: December 2019

High intensity colorless distributed combustion has been a promising combustion technique as it enables much reduced pollutant emissions such as NO and CO, as well as more thermal uniformity, flame stability and combustion efficiency. The main requirement for achieving distributed conditions is to provide controlled entrainment of reactive hot product gases into the fresh mixture prior to ignition. In this way, the oxygen concentration is reduced, which results in lower reaction rates, promoting longer mixing times and volumetric distribution of the reaction zones. Though distributed combustion has been extensively studied for various heat loads and intensities, fuels, geometries, there is limited information related to fuel flexibility. Therefore, it is of interest to investigate hydrogen enriched gaseous fuels for greater understanding of low calorific high flame speed fuels in a distributed combustion system. Three various hydrogen content gaseous fuel (40–60% by volume) were investigated in a swirl-stabilized burner for this study, through the use of either N2 or CO2 as the diluent in order to achieve distributed conditions. The OH* chemiluminescence flame signatures were obtained in the flame front and emissions were measured from the combustor exit. The results showed that both the hydrogen concentration and diluent type considerably impacted the oxygen concentration at which transition to CDC occurred. Distributed conditions were achieved at oxygen concentrations of 10–12% with entrained N2 and 13–15% with entrained CO2 for various gaseous fuels consumed. It was determined that the transition to CDC occurred at a lower oxygen concentration for high hydrogen content fuels due to the higher flame speed of hydrogen. The flame images demonstrated that the flashback propensity of the gaseous fuels were eliminated and enhanced flame stability was achieved under the favorable CDC conditions. For NO pollutant emission, ultra-low NO level was achieved under CDC (less than 1 ppm) while CO pollutant emission decreased gradually with condition approaching distributed conditions, and then increased slightly due to the lower flammability limit and dissociation of CO2.
Additive Manufacturing and Hot Fire Testing of Complex Injectors With Integrated Temperature Sensors
Authors: Islam Md Nawshad Arslan , Hossain Md. Amzad , Choudhuri Ahsan , Morton Philip , Wicker Ryan
Published: December 2019

The article presents an exploration of design and prototyping of oxy-fuel injectors with integrated temperature sensing capabilities using powder bed fusion additive manufacturing (AM) technologies. A primary focus of this work was to develop powder removal techniques to completely remove sintered powders from internal cavities, which facilitated the implementation of complex injector geometries as well as sensor placements within the parts. It was found that submerging the part in liquid nitrogen, in combination with exposure to ultrasonic vibration, provided effective powder removal. Mechanical testing of fabricated components and test coupons showed no significant change in the mechanical strength of the part due to the addition of liquid nitrogen which creates a thermal shock. Metallography and powder characterization through the use of SEM and EDS showed no change in metallurgical properties of the parts due to the use of liquid nitrogen and ultrasonic energy. The injectors were then test fired in both atmospheric and high-pressure conditions at different firing inputs (55–275 kW).
Cylindrical Parabolic Trough Concentrator and Solar Tower Comparison in an Integrated Solar Combined Cycle Power Plant
Authors: Bravo Héctor J. , Ramos José C. , Celis César
Published: December 2019

The intermittency of renewable energies continues to be a limitation for their more widespread application because their large-scale storage is not yet practical. Concentrating solar power (CSP) has the possibility of thermally storing this energy to be used in times of higher demand at a more feasible storage price. The number of concentrated solar energy related projects have grown rapidly in recent years due to the advances in the associated solar technology. Some of the remaining issues regarding the associated high investment costs can be solved by integrating the solar potential into fossil fuel generation plants. An integrated solar combined cycle system (ISCCS) tends to be less dependent to climatic conditions and needs less capital inversion than a CSP system, letting the plant be more reliable and more economically feasible. In this work thus, two technologies of solar concentration (i) parabolic trough cylinder (PTC) and (ii) solar tower (ST) are initially integrated into a three-pressure levels combined cycle power plant. The proposed models are then modeled, simulated and properly assessed. Design and off design point computations are carried out taking into account local environmental conditions such as ambient temperature and direct solar radiation (DNI). The 8760 hourly-basis simulations carried out allow comparing the thermal and economic performance of the different power plant configurations accounted for in this work. The results show that injecting energy into the cycle at high temperatures does not necessarily imply a high power plant performance. In the studied plant configurations, introducing the solar generated steam mass flow rate at the evaporator outlet is slightly more efficient than introducing it at cycle points where temperatures are higher. At design point conditions thus, the plant configuration where the referred steam mass flow rate is introduced at the evaporator outlet generates 0.42% more power than those in which the steam is injected at higher cycle temperatures. At off design point conditions this value is reduced to 0.37%. The results also show that the months with high DNI values and those with low mean ambient temperatures are not necessarily the months which lead to the highest power outputs. In fact a balance between these two parameters, DNI and ambient temperature, leads to an operating condition where the power output is the highest. All plant configurations analyzed here are economically feasible, even so PTC related technologies tend to be more economically feasible than ST ones due to their lower investment costs.
Clinical Evaluation of Three Commercial PCR Assays for the Detection of Macrolide Resistance in Mycoplasma genitalium
Authors: Le Roy Chloé , Bébéar Cécile , Pereyre Sabine
Published: December 2019

As macrolide resistance in
Mycoplasma genitalium
is increasing worldwide, macrolide resistance-associated mutations should be assessed in
M. genitalium
-positive specimens. New commercial kits are available for detection of macrolide resistance concurrently with
M. genitalium
. We prospectively evaluated the handling and clinical performances of three commercial kits for detection of macrolide resistance in
M. genitalium
.
“Researcher for a Day”: Creating and Shaping a New Generation of Scientific and Medical Researchers
Authors: Simard Jean-Luc , Omar Rabeea F. , Boissinot Maurice , Bergeron Michel G.
Published: December 2019

Science is the engine of prosperity, helping society respond to the important issues it faces. We are presently witnessing a worldwide decline in high school students’ interest in science, regardless of gender. To overcome this problem, developing science promotion programs and activities that inspire young people to become the scientists of tomorrow is critical. We strongly believe in the leadership of research centers in creating such programs, which could have a significant impact on the next generation of scientists. Here we present the ‘Researcher for a Day’ program, which offers senior high school students immersion days in a scientific workplace dedicated to microbiology, as an example for other institutions that would like to implement such a program. Researcher for a Day has already helped more than 4,000 young students who are considering their career choices discover the world of science. Similar approaches could be implemented virtually anywhere to extend these efforts to promote science among young people.
Molecular Mechanisms of Conidial Germination in
Aspergillus
spp
Authors: Baltussen Tim J. H. , Zoll Jan , Verweij Paul E. , Melchers Willem J. G.
Published: December 2019

Aspergilli produce conidia for reproduction or to survive hostile conditions, and they are highly effective in the distribution of conidia through the environment. In immunocompromised individuals, inhaled conidia can germinate inside the respiratory tract, which may result in invasive pulmonary aspergillosis. The management of invasive aspergillosis has become more complex, with new risk groups being identified and the emergence of antifungal resistance.
Airway Mucus Restricts Neisseria meningitidis Away from Nasopharyngeal Epithelial Cells and Protects the Mucosa from Inflammation
Authors: Audry Mathilde , Robbe-Masselot Catherine , Barnier Jean-Philippe , Gachet Benoit , Saubaméa Bruno , Schmitt Alain , Schönherr-Hellec Sophia , Léonard Renaud , Nassif Xavier , Coureuil Mathieu
Published: December 2019

N. meningitidis
is transmitted from person to person by aerosol droplets produced by breathing, talking, or coughing or by direct contact with a contaminated fluid. The natural reservoir of
N. meningitidis
is the human nasopharynx mucosa, located at the back of the nose and above the oropharynx. The means by which meningococci cross the nasopharyngeal wall is still under debate, due to the lack of a convenient and relevant model mimicking the nasopharyngeal niche. Here, we took advantage of Calu-3 cells grown in air interface culture to study how meningococci colonize the nasopharyngeal niche. We report that the airway mucus is both a niche for meningococcal growth and a protective barrier against
N. meningitidis
infection. As such,
N. meningitidis
behaves like commensal bacteria and is unlikely to induce infection without an external trigger.
Case of significantly delayed divalproex-induced thrombocytopaenia
Authors: Park Andrew , Shapiro Bryan , Hedayati Bobak , Faziola Lawrence
Published: December 2019

We describe a 48-year-old male patient on long-term divalproex treatment for bipolar disorder who developed grade II thrombocytopaenia after approximately 18 years of therapy. Abrupt cessation of divalproex led to immediate platelet level reconstitution.
Paediatric migraine with visual hallucination auras appearing in the form of a human body
Authors: Akiyama Osamu , Kondo Akihide , Akiyama Iwao
Published: December 2019

The most common type of migraine aura is multifaceted visual aura, such as scintillating scotoma or geometrical patterns, visual hallucinations in which a physical body is extremely rare. We report a paediatric case of migraine in which visual hallucinations appeared as auras in the form of a human body. The patient was an 11-year-old girl suffering from migraine with curious visual aura. The auras were atypical visual hallucinations that were sometimes accompanied by auditory hallucinations. Approximately 5–20 min before the headache, the patient would see a middle-aged man wearing sunglasses in her field of vision. Acetaminophen (10 mg/kg) and Japanese herbal medicine administered when necessary effectively treated the headaches. Finally, the patient was no longer complaining of her hallucination auras. Although the pathophysiology of migraines accompanied by auras is unclear, it appears that cerebral blood flow and cortical spreading depression are involved in auras.
Establishment and assessment of the hepatic venous pressure gradient using biofluid mechanics (HVPGBFM): protocol for a prospective, randomised, non-controlled, multicentre study
Authors: Lin Jia-Yun , Zhang Chi-Hao , Zheng Lei , Li Hong-Jie , Zhu Yi-Ming , Fan Xiao , Li Feng , Xia Yan , Huang Ming-Zhe , Yang Sun-Hu , Qi Xiao-Liang , Huo Hai-Zhong , Chen Hui-Song , Lou Xiao-Lou , Luo Meng
Published: December 2019

Introduction

Portal hypertension (PH) is a severe disease with a poor outcome. Hepatic venous pressure gradient (HVPG), the current gold standard to detect PH, is available only in few hospitals due to its invasiveness and technical difficulty. This study aimed to establish and assess a novel model to calculate HVPG based on biofluid mechanics.

Methods and analysis

This is a prospective, randomised, non-controlled, multicentre trial. A total of 248 patients will be recruited in this study, and each patient will undergo CT, blood tests, Doppler ultrasound and HVPG measurement. The study consists of two independent and consecutive cohorts: original cohort (124 patients) and validation cohort (124 patients). The researchers will establish and improve the HVPG using biofluid mechanics (HVPGBFM)model in the original cohort and assess the model in the validation cohort.

Ethics and dissemination

The study was approved by the Scientific Research Projects Approval Determination of Independent Ethics Committee of Shanghai Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine (approval number 2017–430 T326). Study findings will be disseminated through peer-reviewed publications and conference presentations.

Trial registration number

NCT03470389.
The premature closure of ROMPA clinical trial: mortality reduction in septic shock by plasma adsorption
Authors: Giménez-Esparza Carola , Portillo-Requena Cristina , Colomina-Climent Francisco , Allegue-Gallego José Manuel , Galindo-Martínez María , Mollà-Jiménez Cristina , Antón-Pascual José Luis , Mármol-Peis Enrique , Dólera-Moreno Cristina , Rodríguez-Serra Manuel , Martín-Ruíz José Luis , Fernández-Arroyo Pablo Juan , Blasco-Císcar Eugenia María , Cánovas-Robles José , González-Hernández Enrique , Sánchez-Morán Fernando , Solera-Suárez Manuel , Torres-Tortajada Jesús , Palazón-Bru Antonio , Gil-Guillen Vicente F
Published: December 2019

Objectives

Coupled Plasma Filtration and Adsorption (CPFA) use in septic shock remains controversial. The objective is to clarify whether the application of high doses of CPFA in addition to the current clinical practice could reduce hospital mortality in septic shock patients in Intensive Care Units at 28 days and at 90 days follow-up.

Design

We designed a prospective randomised clinical trial, Reducción de la Mortalidad Plasma-Adsorción (ROMPA), to demonstrate an absolute mortality reduction of 20% (α=0.05; 1-β=0.8; n=190 (95×2)).

Setting

Being aware of the pitfalls associated with previous medical device trials, we developed a training programme to improve CPFA use (especially clotting problems). The protocol was approved by the ethics committees of all participating centres. Circumstances beyond our control produced a change in recruitment conditions unacceptable to ROMPA researchers and the trial was discontinued.

Participants

By closure, five centres from an initial 10 fulfilled the necessary trial criteria, with 49 patients included, 30 in the control group (CG) and 19 in the intervention group (IG).

Intervention

CPFA.

Main outcome measures

Hospital mortality at 28 days and 90 days follow-up.

Results

After 28 days, 14 patients died (46.7%) from the CG and 11 (57.9%) from the IG, not reaching statistical significance (p=0.444). At 90 days, 19 patients had died (63.3%) from the CG and 11 patients (57.9%) from the IG, (p=0.878). The adjustment by propensity score or the use of the Kaplan-Meier technique failed to achieve statistical difference, neither by Intention to Treat nor by the Actual Intervention Received.

Conclusion

We herewith present the results gained from the prematurely closed trial. The results are inconclusive due to low statistical power but we consider that this data is of interest for the scientific community and potentially necessary for any ensuing debate.

Register

NCT02357433 in clinicaltrials.gov.
Machine learning of physiological waveforms and electronic health record data to predict, diagnose and treat haemodynamic instability in surgical patients: protocol for a retrospective study
Authors: Cannesson Maxime , Hofer Ira , Rinehart Joseph , Lee Christine , Subramaniam Kathirvel , Baldi Pierre , Dubrawski Artur , Pinsky Michael R
Published: December 2019

Introduction

About 42 million surgeries are performed annually in the USA. While the postoperative mortality is less than 2%, 12% of all patients in the high-risk surgery group account for 80% of postoperative deaths. New onset of haemodynamic instability is common in surgical patients and its delayed treatment leads to increased morbidity and mortality. The goal of this proposal is to develop, validate and test real-time intraoperative risk prediction tools based on clinical data and high-fidelity physiological waveforms to predict haemodynamic instability during surgery.

Methods and analysis

We will initiate our work using an existing annotated intraoperative database from the University of California Irvine, including clinical and high-fidelity waveform data. These data will be used for the training and development of the machine learning model (Carnegie Mellon University) that will then be tested on prospectively collected database (University of California Los Angeles). Simultaneously, we will use existing knowledge of haemodynamic instability patterns derived from our intensive care unit cohorts, medical information mart for intensive care II data, University of California Irvine data and animal studies to create smart alarms and graphical user interface for a clinical decision support. Using machine learning, we will extract a core dataset, which characterises the signatures of normal intraoperative variability, various haemodynamic instability aetiologies and variable responses to resuscitation. We will then employ clinician-driven iterative design to create a clinical decision support user interface, and evaluate its effect in simulated high-risk surgeries.

Ethics and dissemination

We will publish the results in a peer-reviewed publication and will present this work at professional conferences for the anaesthesiology and computer science communities. Patient-level data will be made available within 6 months after publication of the primary manuscript. The study has been approved by University of California, Los Angeles Institutional review board. (IRB #19–0 00 354).