bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhanced Ground Source Heat Pump System With Thermal Storage System
Authors: Taira Hirotoshi , Sato Takashi , Kakizaki Takao , Oguma Masahito
Published: January 2019

The short-cycling operation of a heat pump decreases energy consumption efficiency. Short-cycling operations of ground source heat pump system (GSHP) occur when the ON/OFF control of a heat pump is used in a partial load condition. It is considered effective that GSHP with capacity controls installs to suppress short-cycling operations. However, there is no report on any continuous operations by capacity control GSHP in actual operations. We confirmed that GSHP (water to water) with capacity control operates short-cycling in the residence. Short-cycling operations occurred with a sudden load fluctuation due to opening or closing of the valves. We conducted effective verification experiments of the thermal storage device at the artificial heat load fluctuations condition. When the thermal storage device installed upstream brine circulation line of the heat pump with the capacity control, continuous operations are performed. It was under the condition at the heating heat load of 5 kW is turned ON/OFF every 20 min. In this case, energy consumption efficiency of a heat pump is 13% higher than the efficiency without the thermal storage device.
A Novel Vibration Suppression Device for Floating Offshore Wind Generator
Authors: Xu Xun , Lai Fen , Li Guojun , Zhu Xiangyuan , Zhu Liping
Published: January 2019

With the increasing demand for clean energy, offshore wind power is developing rapidly. But compared to onshore situation, the working environment at sea is very complicated. In order to ensure the stable operation of generators, higher requirements are put forward for the capability of offshore wind power structures to resist wind and waves. This paper proposes a new combined vibration suppressing device, which can be used to suppress the swaying vibration of offshore floating wind generator under waves. The floating wind power station tower was modeled, the wave force and the torsion force of the tower were analyzed, and the fluid structure interaction numerical simulation was carried out. The calculation results demonstrate that the amplitudes of the tower torsion angle have been attenuated by 8%, 11%, and 17% with different vibration suppression devices which are tuned mass damper (TMD), tuned liquid damper (TLD), and a tuned immersed mass and liquid damper. In this case, the new combined device has the best vibration suppression performance. It is validated that compared to the other two single vibration suppression devices, the new combined device has better vibration suppression capacity, and a new way is provided to design the vibration suppression device for offshore floating wind power station.
Potential Impacts of Net-Zero Energy Buildings With Distributed Photovoltaic Power Generation on the U.S. Electrical Grid
Authors: Kim Dongsu , Cho Heejin , Luck Rogelio
Published: January 2019

This study evaluates the potential aggregate effects of net-zero energy building (NZEB) implementations on the electrical grid in a simulation-based analysis. To estimate the impact of NZEBs on the electrical grid, a simulation-based study of an office building with a grid-tied photovoltaic (PV) power generation system is conducted. This study assumes that net-metering is available for NZEBs such that the excess on-site PV generation can be fed to the electrical grid. The impact of electrical energy storage (EES) within NZEBs on the electrical grid is also considered in this study. Different levels of NZEB adoption are examined: 20%, 50%, and 100% of the U.S. office building stock. Results indicate that significant penetration of NZEBs could potentially affect the current U.S. electricity demand profiles by reducing purchased electricity from the electrical grid and by increasing exported electricity to the electrical grid during peak hours. Annual electricity consumption of simulated office NZEBs in the U.S. climate locations is in the range of around 94–132 kWh/m2 yr. Comparison of hourly electricity demand profiles for the actual U.S. demand versus the calculated net-demand on a national scales indicates that the peak percentage difference of the U.S. net-electricity demand includes about 10.7%, 15.2%, and 9.3% for 100% of the U.S. NZEB stock on representative summer, transition, and winter days, respectively. Using EES within NZEBs, the peak percentage differences are reduced and shifted to the afternoon, including 8.6%, 13.3%, and 6.3% for 100% of the U.S. NZEB stock on each representative day.
Exergy Optimization of a Novel Combination of a Liquid Air Energy Storage System and a Parabolic Trough Solar Collector Power Plant
Authors: Derakhshan Shahram , Khosravian Mohammadreza
Published: January 2019

In this paper, a parabolic trough solar collector (PTSC) plant is combined with a liquid air energy storage (LAES) system. The genetic algorithm (GA) is used to optimize the proposed system for different air storage mass flow rates. The roundtrip exergy ratio is considered as the objective function and pressures of six points and mass flow rates of five points are considered as design parameters. The effects of some environmental and key parameters such as different radiation intensities, ambient temperatures, output pressures of the second compressor, and mass flow rates of the collectors fluid on the exergy ratio are investigated. The results revealed that the system could produce 17526.15 kJ/s (17.5 MW) power in high demands time and 2233.48 kJ/s (2.2 MW) power in low demands time and the system shows that a value of 15.13% round trip exergy ratio is achievable. Furthermore, the exergy ratio decreased by 5.1% when the air storage mass flow rate increased from 10 to 15 kg/s. Furthermore, the exergy ratio decreases by increasing the collectors inside fluid mass flow rate or by decreasing radiation intensity.
A Novel One-Dimensional–Three-Dimensional Coupled Method to Predict Surge Boundary of Centrifugal Compressors
Authors: Zhang Meijie , Zheng Xinqian , Huang Qiangqiang , Sun Zhenzhong
Published: January 2019

Compression systems are widely employed in gas turbine engines, turbocharged engines, and industry compression plants. The stable work of compression systems is an essential precondition for engine performance and safety. A compression system in practice usually consists of upstream and downstream pipes, compressors, plenums and throttles. When a compression system encounters the surge, the flows in the compressor present complex three-dimensional patterns but the flows of other components might present relatively simple one-dimensional patterns. Based on these flow characteristics, this paper proposes a novel simulation method, where one-dimensional and three-dimensional (1D–3D) calculations are coupled, to predict the surge boundary of centrifugal compressors. To validate this method, a high-speed centrifugal compressor is studied both by the proposed 1D–3D coupled method and experimentally. The results show that the differences between the predicted and experimentally determined stable flow range are lower than 5% until the Mach number of blade outlet tip tangential velocity reaches around 1.3. Besides, this method can correctly predict the instantaneous compressor performance during the surge cycle, so it can also be used to explore the surge mechanism and evaluate the blade dynamic force response in the future.
Numerical Analysis of the Combustion Process in Dual-Fuel Engines With Direct Injection of Natural Gas
Authors: Jud Michael , Wieland Christoph , Fink Georg , Sattelmayer Thomas
Published: January 2019

An efficient computational fluid dynamics model for predicting high pressure dual-fuel combustion is one of the most essential steps in order to improve the concept, to reduce the number of experiments and to make the development process more coste-efficient. For Diesel and natural gas such a model developed by the authors is first used to analyze the combustion process with respect to turbulence chemistry interaction and to clarify the question whether the combustion process is limited by chemistry or the mixing process. On the basis of these findings a reduced reaction mechanism is developed in order to save up to 35% of computing time. The prediction capability of the modified combustion model is tested for different gas injection timings representing different degrees of premixing before ignition. Compared to experimental results from a rapid compression expansion machine, the shape of heat release rate, the ignition timing of the gas jet and the burnout are well predicted. Finally, misfiring observed at different geometric configurations in the experiment are analyzed with the model. It is identified that in these geometric configurations at low temperature levels the gas jet covers the preferred ignition region of the diesel jet. Since the model is based on the detailed chemistry approach, it can in future also be used for other fuel combinations or for predicting emissions.
GTL Kerosene and N-Butanol in RCCI Mode: Combustion and Emissions Investigation
Authors: Soloiu Valentin , Moncada Jose , Gaubert Remi , Harp Spencer , Ilie Marcel , Wiley Justin
Published: January 2019

High reactivity gas-to-liquid kerosene (GTL) was investigated with port fuel injection (PFI) of low reactivity n-butanol to conduct reactivity controlled compression ignition (RCCI). In the preliminary stage, the GTL was investigated in a constant volume combustion chamber, and the results indicated a narrower negative temperature coefficient (NTC) region than ultra-low sulfur diesel (ULSD#2). The engine research was conducted at 1500 RPM and various loads with early n-butanol PFI and dual DI pulses of GTL at 60 crank angle degrees (CAD) before top dead center (TDC) and at a timing close to TDC. Boost and PFI fractions (60% by mass n-butanol) were kept constant in order to analyze the fuel reactivity effect on combustion. Conventional diesel combustion (CDC) mode with a single injection and the same combustion phasing (CA50) was used as an emissions baseline for RCCI. RCCI increased ignition delay and combustion duration decreased compared to CDC. Results showed that in order to maintain CA50 for RCCI within 1 CAD, GTL mass required for the first DI pulse to be 15% lower than that of ULSD#2 at higher loads. Peak heat release rate decreased for GTL by 25% given the high volatility and low viscosity of GTL. In general, using GTL, NOx and soot levels were reduced across load points by up to 15% to 30%, respectively, compared to ULSD RCCI, while maintaining RCCI combustion efficiency at 93–97%. Meanwhile, reductions of 85% in soot and 90% in NOx were determined when using RCCI compared to CDC. The more favorable heat release placement of GTL led to increased thermal efficiency by 3% at higher load compared to ULSD#2. The higher volatility and increased reactivity for GTL achieved lower UHC and CO than ULSD#2 at lower load. The study concluded that GTL offered advantages when used with n-butanol for this RCCI fueling configuration.
Effects of N-Butanol Content on the Dual-Fuel Combustion Mode With CNG at Two Engine Speeds
Authors: Meng Xiangyu , Long Wuqiang , Zhou Yihui , Bi Mingshu , Lee Chia-Fon F.
Published: January 2019

Because of the potential to reduce NOx and PM emissions simultaneously and the utilization of biofuel, diesel/compressed natural gas (CNG) dual-fuel combustion mode with port injection of CNG and direct injection of diesel has been widely studied. While in comparison with conventional diesel combustion mode, the dual-fuel combustion mode generally leads lower thermal efficiency, especially at low and medium load, and higher carbon monoxide (CO) and total hydrocarbons (THC) emissions. In this work, n-butanol was blended with diesel as the pilot fuel to explore the possibility to improve the performance and emissions of dual-fuel combustion mode with CNG. Various pilot fuels of B0 (pure diesel), B10 (90% diesel/10% n-butanol by volume basis), B20 (80% diesel/20% n-butanol) and B30 (70% diesel/30% n-butanol) were compared at the CNG substitution rate of 70% by energy basis under the engine speeds of 1400 and 1800 rpm. The experiments were carried out by sweeping a wide range of pilot fuel start of injection timings based on the same total input energy including pilot fuel and CNG. As n-butanol was added into the pilot fuel, the pilot fuel/CNG/air mixture tends to be more homogeneous. The results showed that for the engine speed of 1400 rpm, pilot fuel with n-butanol addition leads to a slightly lower indicated thermal efficiency (ITE). B30 reveals much lower NOx emission and slightly higher THC emissions. For the engine speed of 1800 rpm, B20 can improve ITE and decrease the NOx and THC emissions simultaneously relative to B0.
Fuel Consumption and Emissions in Transient Operation During Ship Maneuvering
Authors: Dahms Felix , Reska Michael , Püschel Marko , Nocke Jürgen , Hassel Egon
Published: January 2019

The following article details a method for the optimization and improved use of the internal combustion engine as main propulsion. The focus here is not on new propulsion systems or combustion processes, but on the characterization of the typical usage of existing systems in order to enable better utilization.

As one major potential for improvement, the transient machinery operation is examined and discussed in this article. Higher fuel consumption and higher emissions occur compared with stationary engine operation in that operation mode. Experimental data from test bed (“Caterpillar MaK 6M20”) measurements are presented which explain the consequences of transient operation. Furthermore, appropriate analyzing methods to evaluate this operation mode are shown. Finally, a modelling approach is presented using the data for calibration and validation of an engine simulation model.

The most significant part to predict real transient efficiency and emissions is the in-cylinder process and especially its combustion process. Therefore, the simulation model does not use engine maps but a mostly physically based engine model by using thermodynamic approaches and chemical reaction kinetics. The specific application of that simulation model for four-stroke medium-speed engines covers the behavior of transient operation during ship maneuverings since it is developed for integration into a ship engine simulator.
Predictive CFD Modeling of Diesel Engine Combustion Using an Efficient Workflow Based on Tabulated Chemistry
Authors: Tap Ferry , Meijer Casper , Goryntsev Dmitry , Starikov Anton , Tvrdojevic Mijo , Priesching Peter
Published: January 2019

The use of 3D CFD combustion models based on tabulated chemistry is becoming increasingly popular. Especially the runtime benefit is attractive, as the tabulated chemistry method allows to include state-of-the-art chemical reaction schemes in CFD simulations. In this work, the Tabkin FGM combustion model in AVL FIRE™ is used to assess the predictivity on a large database of a light-duty Diesel engine measurements. The AVL TABKIN™ software is used to create the chemistry look-up tables for the Tabkin FGM model.

The TABKIN software has been extended with the kinetic soot model, where the soot mass fraction calculation is done during the chemistry tabulation process, as well as an NO model using a second progress variable. From recent validation studies, a best-practice and nearly automated workflow has been derived to create the look-up tables for Diesel engine applications based on minimal input. This automated modeling workflow is assessed in the present study.

A wide range of parameter variations are investigated for 5 engine load points, with and without EGR, in total 186 cases. This large number of CFD simulations is run in an automated way and the parameters of the CFD sub-models are kept equal as well as all numerical settings.

Results are presented for combustion and emissions (NO and soot). Combustion parameters and NO emissions correlate very well to the experimental database with R2 values above 0.95. Soot predictions give order-of-magnitude agreement for most of the cases; the trend however is not always respected, which limits the overall correlation for all cases together, as reported by other authors. Further fundamental research on modeling soot formation and oxidation process remains required to improve the models. In terms of CPU time, the present study was executed on an off-the-shelf HPC cluster, using 8 CPU cores per case and requiring around 3 hrs of wall-time per case, e.g. such a large set of calculations can be simulated overnight on a standard HPC cluster.
Influence of Diesel Fuel Injection Characteristics on Dual-Fuel Combustion Modes in a Large-Bore, Medium-Speed Engine
Authors: Klingbeil Adam , Hong Seunghyuck , Primus Roy J.
Published: January 2019

Experiments were conducted on a large bore, medium speed, single cylinder, diesel engine to investigate operation with substitution ratio of natural gas varying from 0 to 93% by energy. As reported in a previous publication [1], these data were used to validate an analytical methodology for predicting performance and emissions under a broad spectrum of energy substitution ratios. For this paper, these experimental data are further analyzed to better understand the performance and combustion behavior under natural gas substitution ratios of 0%, 60% and 93%. These results show that by transitioning from diesel to 60% dual-fuel (60% NG substitution ratio), an improvement in the NOx-efficiency trade-off was observed that represented a ∼3% improvement in efficiency at constant NOx. Further, the transition from 60% dual-fuel to 93% dual-fuel (93% NG substitution ratio) resulted in additional efficiency improvement with a simultaneous reduction in NOx emissions. The data suggest that this improvement can be attributed to the premixed nature of the high substitution ratio. Furthermore, the results show that high cycle-to-cycle variation was observed for the 93% dual-fuel combustion tests. Further analysis, along with diesel injection rate measurements, show that the observed extreme sensitivity of the combustion event can be attributed to critical parameters such as diesel fuel quantity and injection timing. Results suggest a better understanding of the relative importance of combustion system components and operating conditions in controlling cycle-to-cycle variation of combustion process.
Comparison of Cylinder Pressure Measurements on a Heavy-Duty Diesel Engine Using a Switching Adapter
Authors: Dempsey Adam B. , Seiler Patrick J. , Johnson Simon
Published: January 2019

In this study, a variety of piezoelectric pressure transducer designs and mounting configurations were compared for measuring in-cylinder pressure on a heavy-duty single-cylinder diesel engine. A unique cylinder head design was used which allowed cylinder pressure to be measured simultaneously in two locations. In one location, various piezoelectric pressure transducers and mounting configurations were studied. In the other location, a Kistler water-cooled switching adapter with a piezoresistive pressure sensor was used. The switching adapter measured in-cylinder pressure during the low pressure portion of the cycle. During the high pressure portion of the cycle the sensor is protected from the high pressure and high temperature gases in the cylinder. Therefore, the piezoresistive sensor measured in-cylinder pressure highly accurately, without the impacts of short term thermal drift, otherwise known as thermal shock. Additionally, the piezoresistive sensor is an absolute pressure sensor which does not require a baseline or “pegging” on every engine cycle. With this measurement setup, the amount of thermal shock and induced measurement variability was accurately assessed for the piezoelectric sensors. Data analysis techniques for quantifying the accuracy of a piezoelectric cylinder pressure measurements are also presented and discussed. It was observed that all the piezoelectric transducers investigated yielded very similar results regarding compression pressure, start of combustion, peak cylinder pressure, and the overall heat release rate shape. Differences emerged when studying the impact of the transducer mounting (e.g., recessed vs. flush-mount). Recessed-mount transducers tended to yield a more accurate measurement of the cycle-to-cycle variability when compared to the baseline piezoresistive sensor. This is thought to be due to reduced levels of thermal shock, which can vary from cycle-to-cycle.
A saliva-based rapid test to quantify the infectious subclinical malaria parasite reservoir
Authors: Tao Dingyin , McGill Brent , Hamerly Timothy , Kobayashi Tamaki , Khare Prachi , Dziedzic Amanda , Leski Tomasz , Holtz Andrew , Shull Bruce , Jedlicka Anne E. , Walzer Andrew , Slowey Paul D. , Slowey Christopher C. , Nsango Sandrine E. , Stenger David A. , Chaponda Mike , Mulenga Modest , Jacobsen Kathryn H. , Sullivan David J. , Ryan Sadie J. , Ansumana Rashid , Moss William J. , Morlais Isabelle , Dinglasan Rhoel R.
Published: January 2019

A noninvasive malaria rapid test assesses subclinical carriage of
Plasmodium falciparum
(human malaria) parasites at the point of need.
Identifying purine nucleoside phosphorylase as the target of quinine using cellular thermal shift assay
Authors: Dziekan Jerzy M. , Yu Han , Chen Dan , Dai Lingyun , Wirjanata Grennady , Larsson Andreas , Prabhu Nayana , Sobota Radoslaw M. , Bozdech Zbynek , Nordlund Pär
Published: January 2019

A cellular thermal shift assay (CETSA) protocol identifies and resolves antimalarial drug targets in
P. falciparum
.
Nanoscavenger provides long-term prophylactic protection against nerve agents in rodents
Authors: Zhang Peng , Liu Erik J. , Tsao Caroline , Kasten Shane A. , Boeri Michael V. , Dao Thuy L. , DeBus Sandra J. , Cadieux C. Linn , Baker Cetara A. , Otto Tamara C. , Cerasoli Douglas M. , Chen Yantao , Jain Priyesh , Sun Fang , Li Wenchen , Hung Hsiang-Chieh , Yuan Zhefan , Ma Jinrong , Bigley Andrew N. , Raushel Frank M. , Jiang Shaoyi
Published: January 2019

A catalytic nanoscavenger with long blood residence time provides long-term prophylactic protection against nerve agents in animal models.
Barrier to Resistance of Dolutegravir in Two-Drug Combinations
Authors: Yoshinaga Tomokazu , Miki Shigeru , Kawauchi-Miki Shinobu , Seki Takahiro , Fujiwara Tamio
Published: January 2019

A major concern when using two-drug anti-HIV regimens is the risk of viral resistance. However, no techniques to evaluate the barrier to resistance of two-drug combinations
in vitro
have been reported.
Membrane Proteomes and Ion Transporters in
Bacillus anthracis
and
Bacillus subtilis
Dormant and Germinating Spores
Authors: Chen Yan , Barat Bidisha , Ray W. Keith , Helm Richard F. , Melville Stephen B. , Popham David L.
Published: January 2019

Bacterial endospores can remain dormant and highly resistant to environmental insults for long periods but can also rapidly germinate in response to a nutrient-rich environment. The persistence and subsequent germination of spores contribute to their colonization of new environments and to the spread of certain diseases. Proteins of
Bacillus subtilis
and
Bacillus anthracis
were identified that are associated with the spore membrane, a position that can allow them to contribute to germination. A set of identified proteins that are predicted to carry out ion transport were examined for their contributions to spore formation, stability, and germination. Greater knowledge of spore formation and germination can contribute to the development of better decontamination strategies.
Rad53- and Chk1-Dependent DNA Damage Response Pathways Cooperatively Promote Fungal Pathogenesis and Modulate Antifungal Drug Susceptibility
Authors: Jung Kwang-Woo , Lee Yeonseon , Huh Eun Young , Lee Soo Chan , Lim Sangyong , Bahn Yong-Sun
Published: January 2019

Genome instability is detrimental for living things because it induces genetic disorder diseases and transfers incorrect genome information to descendants. Therefore, living organisms have evolutionarily conserved signaling networks to sense and repair DNA damage. However, how the DNA damage response pathway is regulated for maintaining the genome integrity of fungal pathogens and how this contributes to their pathogenicity remain elusive. In this study, we investigated the DNA damage response pathway in the basidiomycete pathogen
Cryptococcus neoformans
, which causes life-threatening meningoencephalitis in immunocompromised individuals, with an average of 223,100 infections leading to 181,100 deaths reported annually. Here, we found that perturbation of Rad53- and Chk1-dependent DNA damage response pathways attenuated the virulence of
C. neoformans
and increased its susceptibility to certain antifungal drugs, such as amphotericin B and flucytosine. Therefore, our work paves the way to understanding the important role of human fungal DNA damage networks in pathogenesis and antifungal drug susceptibility.
A Tale of Three Species: Adaptation of Sodalis glossinidius to Tsetse Biology,
Wigglesworthia
Metabolism, and Host Diet
Authors: Hall Rebecca J. , Flanagan Lindsey A. , Bottery Michael J. , Springthorpe Vicki , Thorpe Stephen , Darby Alistair C. , Wood A. Jamie , Thomas Gavin H.
Published: January 2019

Human African trypanosomiasis is caused by the
Trypanosoma brucei
parasite. The tsetse fly vector is of interest for its potential to prevent disease spread, as it is essential for
T. brucei
life cycle progression and transmission. The tsetse’s mutualistic endosymbiont
Sodalis glossinidius
has a link to trypanosome establishment, providing a disease control target. Here, we describe a new, experimentally verified model of
S. glossinidius
metabolism. This model has enabled the development of a defined growth medium that was used successfully to test aspects of
S. glossinidius
metabolism. We present
S. glossinidius
as uniquely adapted to life in the tsetse, through its reliance on the blood diet and host-derived sugars. Additionally,
S. glossinidius
has adapted to the tsetse’s obligate symbiont
Wigglesworthia glossinidia
by scavenging a vitamin it produces for the insect. This work highlights the use of metabolic modeling to design defined growth media for symbiotic bacteria and may provide novel inhibitory targets to block trypanosome transmission.
The Transcriptional Cycle Is Suited to Daytime N
2
Fixation in the Unicellular Cyanobacterium “
Candidatus
Atelocyanobacterium thalassa” (UCYN-A)
Authors: Muñoz-Marín María del Carmen , Shilova Irina N. , Shi Tuo , Farnelid Hanna , Cabello Ana María , Zehr Jonathan P.
Published: January 2019

The symbiotic N
2
-fixing cyanobacterium UCYN-A, which is closely related to
Braarudosphaera bigelowii
, and its eukaryotic algal host have been shown to be globally distributed and important in open-ocean N
2
fixation. These unique cyanobacteria have reduced metabolic capabilities, even lacking genes for oxygenic photosynthesis and carbon fixation. Cyanobacteria generally use energy from photosynthesis for nitrogen fixation but require mechanisms for avoiding inactivation of the oxygen-sensitive nitrogenase enzyme by ambient oxygen (O
2
) or the O
2
evolved through photosynthesis. This study showed that symbiosis between the N
2
-fixing cyanobacterium UCYN-A and its eukaryotic algal host has led to adaptation of its daily gene expression pattern in order to enable daytime aerobic N
2
fixation, which is likely more energetically efficient than fixing N
2
at night, as found in other unicellular marine cyanobacteria.
In VivoImaging of the Segregation of the 2 Chromosomes and the Cell Division Proteins ofRhodobacter sphaeroidesReveals an Unexpected Role for MipZ
Authors: Dubarry Nelly , Willis Clare R. , Ball Graeme , Lesterlin Christian , Armitage Judith P.
Published: January 2019

Cell division has to be coordinated with chromosome segregation to ensure the stable inheritance of genetic information. We investigated this coordination in the multichromosome bacteriumRhodobacter sphaeroides. By examining the origin and terminus regions of the two chromosomes, the ParA-like ATPase MipZ and FtsZ, we showed that chromosome 1 appears to be the “master” chromosome connecting DNA segregation and cell division, with MipZ being critical for coordination. MipZ shows an unexpected localization pattern, with MipZ monomers interacting with ParB of the chromosome 1 at the cell poles whereas MipZ dimers colocalize with FtsZ at midcell during constriction, both forming dynamic rings. These data suggest that MipZ has roles inR. sphaeroidesin both controlling septation and coordinating chromosome segregation with cell division.
Antibodies Are Major Drivers of Protection against Lethal Aerosol Infection with Highly Pathogenic
Burkholderia
spp
Authors: Hogan Robert J. , Lafontaine Eric R.
Published: January 2019

Burkholderia pseudomallei
and
Burkholderia mallei
are the causative agents of melioidosis and glanders, respectively. There is no vaccine to protect against these highly pathogenic bacteria, and there is concern regarding their emergence as global public health (
B. pseudomallei
) and biosecurity (
B. mallei
) threats.
Image-Processing Software for High-Throughput Quantification of Colony Luminescence
Authors: Dafni Eyal , Weiner Iddo , Shahar Noam , Tuller Tamir , Yacoby Iftach
Published: January 2019

Luminescent markers are widely used as reporters for various biologically interesting traits. In colony luminescence assays, the levels of luminescence around each colony can be used to compare the levels of traits of interest for different strains, treatments, etc., using quantitative measurements of the luminescence. However, automatic methods of obtaining this data are underdeveloped, making this a laborious manual process, especially in analyzing large numbers of colonies. The significance of this work is in developing an automatic, high-throughput tool for quantitative analysis of colony luminescence assays, which will allow fast collection of qualitative data from these assays and thus increase their overall usability.
Comparison of conventional and videolaryngoscopy blades in neonates
Authors: Kirolos Sandy , O’Shea Joyce E
Published: January 2019

Neonatal intubation is an essential but difficult skill to learn. Videolaryngoscopy allows the airway view to be shared by the intubator and supervisor and improves intubation success. Ideally, a videolaryngoscope (VL) should be usable as a conventional laryngoscope (CL). The aims of this report were to describe differences in the shape of currently available CL and VL blades and to compare the direct airway view obtainable on a neonatal manikin with different laryngoscope blades.

Three main differences were observed; compared with CL, the VL blades have a reduced vertical height, a curved tip and curved body. The direct airway view obtained by the VL is narrower than that obtained with the CL, although the corresponding view on the VL screen is maintained.

Minor adaptation of intubation technique may be required when using a VL. Modifying VL blades to reduce these differences may improve their usefulness as an intubation training tool.
Circulating high sensitivity C reactive protein concentrations and risk of lung cancer: nested case-control study within Lung Cancer Cohort Consortium
Authors: Muller David C , Larose Tricia L , Hodge Allison , Guida Florence , Langhammer Arnulf , Grankvist Kjell , Meyer Klaus , Cai Qiuyin , Arslan Alan A , Zeleniuch-Jacquotte Anne , Albanes Demetrius , Giles Graham G , Sesso Howard D , Lee I-Min , Gaziano J Michael , Yuan Jian-Min , Hoffman Bolton Judith , Buring Julie E , Visvanathan Kala , Le Marchand Loic , Purdue Mark P , Caporaso Neil E , Midttun Øivind , Ueland Per M , Prentice Ross L , Weinstein Stephanie J , Stevens Victoria L , Zheng Wei , Blot William J , Shu Xiao-Ou , Zhang Xuehong , Xiang Yong-Bing , Koh Woon-Puay , Hveem Kristian , Thomson Cynthia A , Pettinger Mary , Engström Gunnar , Brunnström Hans , Milne Roger L , Stampfer Meir J , Han Jiali , Johansson Mikael , Brennan Paul , Severi Gianluca , Johansson Mattias
Published: January 2019

Objectives

To conduct a comprehensive analysis of prospectively measured circulating high sensitivity C reactive protein (hsCRP) concentration and risk of lung cancer overall, by smoking status (never, former, and current smokers), and histological sub-type.

Design

Nested case-control study.

Setting

20 population based cohort studies in Asia, Europe, Australia, and the United States.

Participants

5299 patients with incident lung cancer, with individually incidence density matched controls.

Exposure

Circulating hsCRP concentrations in prediagnostic serum or plasma samples.

Main outcome measure

Incident lung cancer diagnosis.

Results

A positive association between circulating hsCRP concentration and the risk of lung cancer for current (odds ratio associated with a doubling in hsCRP concentration 1.09, 95% confidence interval 1.05 to 1.13) and former smokers (1.09, 1.04 to 1.14) was observed, but not for never smokers (P<0.01 for interaction). This association was strong and consistent across all histological subtypes, except for adenocarcinoma, which was not strongly associated with hsCRP concentration regardless of smoking status (odds ratio for adenocarcinoma overall 0.97, 95% confidence interval 0.94 to 1.01). The association between circulating hsCRP concentration and the risk of lung cancer was strongest in the first two years of follow-up for former and current smokers. Including hsCRP concentration in a risk model, in addition to smoking based variables, did not improve risk discrimination overall, but slightly improved discrimination for cancers diagnosed in the first two years of follow-up.

Conclusions

Former and current smokers with higher circulating hsCRP concentrations had a higher risk of lung cancer overall. Circulating hsCRP concentration was not associated with the risk of lung adenocarcinoma. Circulating hsCRP concentration could be a prediagnostic marker of lung cancer rather than a causal risk factor.
Renovations of neighbourhood parks: long-term outcomes on physical activity
Authors: Cohen Deborah A , Han Bing , Isacoff Jennifer , Shulaker Bianca , Williamson Stephanie
Published: January 2019

Background

Neighbourhood parks are places designed to support physical activity, but are often underutilised. Park renovations are major improvements to the quality of these spaces and usually attract more park users. This study assessed changes in the use of six San Francisco neighbourhood parks and park-based physical activity levels over a 6-year period, during which five of the six parks were renovated.

Methods

We used direct observation to assess park-based physical activity. We used a stepped-wedge study design at three time points in all six parks over 6 years (before all parks were renovated, after two parks were renovated and after an additional three were renovated) to evaluate the short-term and long-term effects of park renovations.

Results

Levels of moderate-to-vigorous physical activity (MVPA) and metabolic equivalent hours expended in the parks increased overall, most immediately after renovation. Age groups responded differently with the largest increases in park use and MVPA among adults and children under age 12, with no changes among teens and seniors.

Conclusions

Park renovations attracted more users and increased park-based MVPA than non-renovated parks and sustained increases over time for adults and children, but not teens or seniors. Park renovations that consider and provide facilities that support varied levels of physical activity and cater to all age groups may foster increased park-based physical activity that can be sustained.
Ziziphus spina-christi leaves methanolic extract alleviates diethylnitrosamine-induced hepatocellular carcinoma in rats
Authors: El-Din Manar Salah , Taha AlShaimaa Mohamed , Sayed Ahmed Abdel-Aziz , Salem Ahmed Mohamed
Published: January 2019

This study evaluated the antitumor activity of a methanolic extract from the leaves of Ziziphus spina-christi (ZSCL) against diethylnitrosamine (DENA)-induced hepatocarcinoma in rats. The phytochemical constituents, in vitro antioxidant and cytotoxic activities of ZSCL extract were investigated. Male Wistar rats were distributed among 6 groups: (i) normal control; (ii) ZSCL1-treated rats (100 mg/kg body mass; “b.m.”); (iii) ZSCL2-treated rats (300 mg/kg b.m.); (iv) rats with DENA-induced hepatocarcinoma; (v and vi) rats with hepatocarcinoma that were treated with either (v) ZSCL1 or (vi) ZSCL2. Serum liver function and levels of oxidative stress were assayed. The expression of hepatocyte growth factor, insulin-like growth factor-1 receptor, B cell lymphoma-2, and matrix metalloproteinase-9 oncogenes were quantified in liver samples. Histological examination of the liver tissues was performed. The ZSCL was rich in essential fatty acids, phytol, and polyphenolic flavones (luteolin and quercetin) with strong free-radical and peroxide scavenging activities and cytotoxic activity. Administration of ZSCL1 and ZSCL2 to the rats produced no toxic effects. DENA induced hepatocellular carcinoma and cholangioma by producing oxidative stress and upregulating the expression of hepatic oncogenes. Treatment of DENA-induced hepatocarcinoma with ZSCL2 ameliorated all of the abnormalities induced by DENA except for cholangioma. In conclusion, the ZSCL (300 mg/kg b.m.) displayed strong therapeutic activity against DENA-induced hepatocellular carcinoma via targeting oxidative stress and oncogenes.
Cinnamaldehyde in flavored e-cigarette liquids temporarily suppresses bronchial epithelial cell ciliary motility by dysregulation of mitochondrial function
Authors: Clapp Phillip W. , Lavrich Katelyn S. , van Heusden Catharina A. , Lazarowski Eduardo R. , Carson Johnny L. , Jaspers Ilona
Published: January 2019

Aldehydes in cigarette smoke (CS) impair mitochondrial function and reduce ciliary beat frequency (CBF), leading to diminished mucociliary clearance (MCC). However, the effects of aldehyde e-cigarette flavorings on CBF are unknown. The purpose of this study was to investigate whether cinnamaldehyde, a flavoring agent commonly used in e-cigarettes, disrupts mitochondrial function and impairs CBF on well-differentiated human bronchial epithelial (hBE) cells. To this end, hBE cells were exposed to diluted cinnamon-flavored e-liquids and vaped aerosol and assessed for changes in CBF. hBE cells were subsequently exposed to various concentrations of cinnamaldehyde to establish a dose-response relationship for effects on CBF. Changes in mitochondrial oxidative phosphorylation and glycolysis were evaluated by Seahorse Extracellular Flux Analyzer, and adenine nucleotide levels were quantified by HPLC. Both cinnamaldehyde-containing e-liquid and vaped aerosol rapidly yet transiently suppressed CBF, and exposure to cinnamaldehyde alone recapitulated this effect. Cinnamaldehyde impaired mitochondrial respiration and glycolysis in a dose-dependent manner, and intracellular ATP levels were significantly but temporarily reduced following exposure. Addition of nicotine had no effect on the cinnamaldehyde-induced suppression of CBF or mitochondrial function. These data indicate that cinnamaldehyde rapidly disrupts mitochondrial function, inhibits bioenergetic processes, and reduces ATP levels, which correlates with impaired CBF. Because normal ciliary motility and MCC are essential respiratory defenses, inhalation of cinnamaldehyde may increase the risk of respiratory infections in e-cigarette users.
Inositol monophosphatase 1 as a novel interacting partner of RAGE in pulmonary hypertension
Authors: Rafikov Ruslan , McBride Matthew L. , Zemskova Marina , Kurdyukov Sergey , McClain Nolan , Niihori Maki , Langlais Paul R. , Rafikova Olga
Published: January 2019

Pulmonary arterial hypertension (PAH) is a lethal disease characterized by progressive pulmonary vascular remodeling. The receptor for advanced glycation end products (RAGE) plays an important role in PAH by promoting proliferation of pulmonary vascular cells. RAGE is also known to mediate activation of Akt signaling, although the particular molecular mechanism remains unknown. This study aimed to identify the interacting partner of RAGE that could facilitate RAGE-mediated Akt activation and vascular remodeling in PAH. The progressive angioproliferative PAH was induced in 24 female Sprague-Dawley rats ( n = 8/group) that were randomly assigned to develop PAH for 1, 2, or 5 wk [right ventricle systolic pressure (RVSP) 56.5 ± 3.2, 63.6 ± 1.6, and 111.1 ± 4.5 mmHg, respectively, vs. 22.9 ± 1.1 mmHg in controls]. PAH triggered early and late episodes of apoptosis in rat lungs accompanied by RAGE activation. Mass spectrometry analysis has identified IMPA1 as a novel PAH-specific interacting partner of RAGE. The proximity ligation assay (PLA) confirmed the formation of RAGE/IMPA1 complex in the pulmonary artery wall. Activation of IMPA1 in response to increased glucose 6-phosphate (G6P) is known to play a critical role in inositol synthesis and recycling. Indeed, we confirmed a threefold increase in G6P ( P = 0.0005) levels in lungs of PAH rats starting from week 1 that correlated with accumulation of phosphatidylinositol (3,4,5)-trisphosphate (PIP3), membrane translocation of PI3K, and a threefold increase in membrane Akt levels ( P = 0.02) and Akt phosphorylation. We conclude that the formation of the newly discovered RAGE-IMPA1 complex could be responsible for the stimulation of inositol pathways and activation of Akt signaling in PAH.
Unravelling the Interplay between Extracellular Acidosis and Immune Cells
Authors: Erra Díaz Fernando , Dantas Ezequiel , Geffner Jorge
Published: December 2018

The development of an acidic tissue environment is a hallmark of a variety of inflammatory processes and solid tumors. However, little attention has been paid so far to analyze the influence exerted by extracellular pH on the immune response. Tissue acidosis (pH 6.0 to 7.0) is usually associated with the course of infectious processes in peripheral tissues. Moreover, it represents a prominent feature of solid tumors. In fact, values of pH ranging from 5.7 to 7.0 are usually found in a number of solid tumors such as breast cancer, brain tumors, sarcomas, malignant melanoma, squamous cell carcinomas, and adenocarcinomas. Both the innate and adaptive arms of the immune response appear to be finely regulated by extracellular acidosis in the range of pH values found at inflammatory sites and tumors. Low pH has been shown to delay neutrophil apoptosis, promoting their differentiation into a proangiogenic profile. Acting on monocytes and macrophages, it induces the activation of the inflammasome and the production of IL-1β, while the exposure of conventional dendritic cells to low pH promotes the acquisition of a mature phenotype. Overall, these observations suggest that high concentrations of protons could be recognized by innate immune cells as a danger-associated molecular pattern (DAMP). On the other hand, by acting on T lymphocytes, low pH has been shown to suppress the cytotoxic response mediated by CD8+ T cells as well as the production of IFN-γby TH1 cells. Interestingly, modulation of tumor microenvironment acidity has been shown to be able not only to reverse anergy in human and mouse tumor-infiltrating T lymphocytes but also to improve the antitumor immune response induced by checkpoint inhibitors. Here, we provide an integrated view of the influence exerted by low pH on immune cells and discuss its implications in the immune response against infectious agents and tumor cells.
Illumination Invariant Motion Detection and Tracking Using SMDWT and a Dense Disparity-Variance Method
Authors: Deepambika V. A. , Rahman M. Abdul
Published: December 2018

The navigation management systems in autonomous vehicles should be able to gather solid information about the immediate environment of the vehicle, discern ambulance from a delivery truck, and react in a proper manner to handle any difficult situation. Separating such information from a vision controlled system is a computationally demanding task for heavy traffic areas in the real world environmental conditions. In such a scenario, we need a robust moving object detection tracking system. To achieve this, we can make use of stereo vision-based moving object detection and tracking, utilizing symmetric mask-based discrete wavelet transform to deal with illumination changes, low memory requirement, and fake motion avoidance. The accurate motion detection in complex dynamic scenes is done by the combined background subtraction and frame differencing technique. For the fast motion track, we can employ a dense disparity-variance method. This SMDWT-based object detection has a maximum and minimum accuracy of 99.62% and 94.95%, respectively. The motion track has the highest accuracy of 79.47% within the time frame of 28.03 seconds. The lowest accuracy of the system is 62.01% within the time frame of 34.46 seconds. From the analysis, it is clear that this proposed method exceptionally outperforms the existing monocular and dense stereo object tracking approaches in terms of low computational cost, high accuracy, and in handling the dynamic environments.
Novel Endoscopic Management of Eroding Laparoscopic Adjustable Gastric Band: A Case Series
Authors: Dellaportas Dionysios , Nastos Constantinos , Theodosopoulos Theodosios , Fragulidis George , Polydorou Andreas , Vezakis Antonios
Published: December 2018

Complications of laparoscopic adjustable gastric bands include migration and slippage of the band, dilation of the proximal gastric pouch, troublesome gastroesophageal reflux symptoms, and erosion of the stomach. The latter occurs in 0.6-12.7% of cases and necessitates removal of the band. Several open and laparoscopic surgical techniques have been described for band extraction, while fully endoscopic techniques have emerged and proven safe. Three cases of eroding gastric bands treated in a single center with fully endoscopic removal of the band are analyzed in this study. Novel use of the duodenoscope and endoscopic retrograde cholangiopancreatography instruments and accessories is described, in order to perform endoscopic division of the plastic band and retraction through the mouth. All three cases were successfully treated utilizing this novel technique. Gastric wall erosion from the band has nonspecific symptoms and various predisposing factors. Removal of the foreign material is required. Endoscopic procedures are effective in 77-92% of cases, avoiding general anaesthesia with low surgical morbidity. As a result patients are discharged early resolving quicker to a normal diet.
Analysis of the Cluster Prominence Feature for Detecting Calcifications in Mammograms
Authors: Cruz-Bernal Alejandra , Flores-Barranco Martha M. , Almanza-Ojeda Dora L. , Ledesma Sergio , Ibarra-Manzano Mario A.
Published: December 2018

In mammograms, a calcification is represented as small but brilliant white region of the digital image. Earlier detection of malignant calcifications in patients provides high expectation of surviving to this disease. Nevertheless, white regions are difficult to see by visual inspection because a mammogram is a gray-scale image of the breast. To help radiologists in detecting abnormal calcification, computer-inspection methods of mammograms have been proposed; however, it remains an open important issue. In this context, we propose a strategy for detecting calcifications in mammograms based on the analysis of the cluster prominence (cp) feature histogram. The highest frequencies of the cp histogram describe the calcifications on the mammography. Therefore, we obtain a function that models the behaviour of the cp histogram using the Vandermonde interpolation twice. The first interpolation yields a global representation, and the second models the highest frequencies of the histogram. A weak classifier is used for obtaining a final classification of the mammography, that is, with or without calcifications. Experimental results are compared with real DICOM images and their corresponding diagnosis provided by expert radiologists, showing that the cp feature is highly discriminative.