bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance Characterization of Alternative Ignition Systems Using Optical Tools in Natural Gas Engines
Authors: Bihari Bipin , Biruduganti Munidhar S. , Torelli Roberto , Singleton Dan
Published: January 2019

Lean-burn combustion dominates the current reciprocating engine R&D efforts due to its inherent benefits of high BTE and low emissions. The ever-increasing push for high power densities necessitates high boost pressures. Therefore, the reliability and durability of ignition systems face greater challenges. In this study, four ignition systems, namely, stock Capacitive discharge ignition (CDI), Laser ignition, Flame jet ignition (FJI), and Nano-pulse delivery (NPD) ignition were tested using a single cylinder natural gas engine. Engine performance and emissions characteristics are presented highlighting the benefits and limitations of respective ignition systems. Optical tools enabled delving into the ignition delay period and assisted with some characterization of the spark and its impact on subsequent processes. It is evident that advanced ignition systems such as Lasers, Flame-jets and Nano-pulse delivery enable extension of the lean ignition limits of fuel/air mixtures compared to base CDI system.
Heat Release Experimental Analysis for RCCI Combustion Optimization
Authors: Ravaglioli V. , Ponti F. , Carra F. , De Cesare M.
Published: January 2019

Over the past years, the increasingly stringent emission regulations for Internal Combustion Engines (ICE) spawned a great amount of research in the field of combustion control optimization. Nowadays, optimal combustion control has become crucial, especially to properly manage innovative Low Temperature Combustion (LTC) strategies, usually characterized by high instability, cycle-to-cycle variability and sensitivity to slight variations of injection parameters and thermal conditions.

Many works demonstrate that stability and maximum efficiency of LTC strategies can be guaranteed using closed-loop control strategies that vary the standard injection parameters (mapped during the base calibration activity) to keep engine torque and center of combustion (CA50) approximately equal to their target values. However, the combination of standard base calibration and closed-loop control is usually not sufficient to accurately control Low Temperature Combustions in transient conditions. As a matter of fact, to properly manage LTC strategies in transient conditions it is usually necessary to investigate the combustion methodology of interest and implement specific functions that provide an accurate feed-forward contribution to the closed-loop controller.

This work presents the experimental analysis performed running a light-duty compression ignited engine in dual-fuel RCCI mode, the goal being to highlight the way injection parameters and charge temperature affect combustion stability and ignition delay. Finally, the paper describes how the obtained results can be used to define the optimal injections strategy in the analyzed operating points, i.e. the combination of injection parameters to be used as a feed-forward for a closed-loop combustion control strategy.
Evaluating Optimization Strategies for Engine Simulations Using Machine Learning Emulators
Authors: Probst Daniel M. , Raju Mandhapati , Senecal Peter K. , Kodavasal Janardhan , Pal Pinaki , Som Sibendu , Moiz Ahmed A. , Pei Yuanjiang
Published: January 2019

This work evaluates different optimization algorithms for Computational Fluid Dynamics (CFD) simulations of engine combustion. Due to the computational expense of CFD simulations, emulators built with machine learning algorithms were used as surrogates for the optimizers.

Two types of emulators were used: a Gaussian Process (GP) and a weighted variety of machine learning methods called SuperLearner (SL). The emulators were trained using a dataset of 2048 CFD simulations that were run concurrently on a supercomputer. The Design of Experiments (DOE) for the CFD runs was obtained by perturbing nine input parameters using a Monte Carlo method. The CFD simulations were of a heavy duty engine running with a low octane gasoline-like fuel at a partially premixed compression ignition mode.

Ten optimization algorithms were tested, including types typically used in research applications. Each optimizer was allowed 800 function evaluations and was randomly tested 100 times. The optimizers were evaluated for the median, minimum, and maximum merits obtained in the 100 attempts. Some optimizers required more sequential evaluations, thereby resulting in longer wall clock times to reach an optimum.

The best performing optimization methods were particle swarm optimization (PSO), differential evolution (DE), GENOUD (an evolutionary algorithm), and Micro-Genetic Algorithm (GA). These methods found a high median optimum as well as a reasonable minimum optimum of the 100 trials. Moreover, all of these methods were able to operate with less than 100 successive iterations, which reduced the wall clock time required in practice.

Two methods were found to be effective but required a much larger number of successive iterations: the DIRECT and MALSCHAINS algorithms. A random search method that completed in a single iteration performed poorly in finding 1 Currently at Southwest Research Institute, San Antonio, Texas optimum designs, but was included to illustrate the limitation of highly concurrent search methods. The last three methods, Nelder-Mead, BOBYQA, and COBYLA, did not perform as well.
SCR-Catalyst Utilisation and Mixing Comparison Using a Novel Biomimetic Flash-Boiling Injector
Authors: Larsson Peter , Ravenhill Paul , Larsson Lars-Uno , Tunestål Per
Published: January 2019

NOx pollution from Diesel engines causes over 10 000 premature deaths annually and the trend is increasing. In order to decrease this growing global problem, exhaust after-treatment systems for Diesel engines have to be improved.

The most common SCR systems in the market place inject an aqueous Urea solution, DEF that evaporates prior the catalytic surface of the SCR-catalyst. Due to a catalytic reaction within the catalyst, NOx is converted nominally into Nitrogen and Water.

Currently, the evaporative process is enhanced by aggressive mixer plates and long flow paths; these, negatively, create extra exhaust back pressure and cool the exhaust gases decreasing engine and catalyst efficiency. To achieve future emission legislation targets SCR efficiency has to be improved especially under low catalyst temperature conditions, plus Ammonia slip has to be avoided as it is now legislated against.

Swedish Biomimetic’s novel μMist® platform technology, inspired by the Bombardier Beetle, injects a hot, effervescent, finely atomised, highly dispersed spray plume of DEF into the exhaust stream. This is achieved by raising the temperature of the DEF, in a closed volume, above its saturated vapour pressure. The DEF is then rapidly released creating effervescent atomisation.

This study investigates a back to back study of the evaporating and mixing behaviour of the μMist® injector and a class leading DEF injector. The test conditions are with and without a mixer plate and the use of two different flow path designs. Spray distribution across the face of the catalyst is assessed by measuring NOx conversion whilst Ammonia slip is also measured post catalyst. This report describes how the novel μMist® injector significantly increases NOx conversion and catalyst surface usage whilst considerably reducing Ammonia slip.
Impacts of Spark Discharge Current and Duration on Flame Development of Lean Mixtures Under Flow Conditions
Authors: Yang Zhenyi , Yu Xiao , Yu Shui , Chen Jianming , Chen Guangyun , Zheng Ming , Reader Graham , Ting David S.-K.
Published: January 2019

Lean or diluted combustion has been considered as an effective strategy to improve the thermal efficiency of spark ignition engines. Under lean or diluted conditions, the combustion speed is reduced by the diluting gas. In order to speed up the combustion, in-cylinder flow is intentionally enhanced to promote the flame propagation. However, it is observed that the flow may make the spark ignition process more challenging due to the shortened discharge duration, the frequent re-strikes of spark plasma and the more complicated interactions between the flow and the flame.

In this research, the effects of spark discharge current level and discharge duration on flame kernel development and flame propagation of lean methane air mixture are investigated under flow velocity of about 25 m/s and background pressure of 4 bar abs in an optical combustion chamber. A dual coil ignition system and an in-house developed current management module are used to create different discharge current levels. The average discharge current levels range from 55 mA, 190 mA, up to 250 mA. Detached flame kernel is observed under some test conditions. The flame propagation speed with the detached flame is generally slower than the flame developed from a flame kernel attached to the spark plug. The flame detachment is related to both the discharge current level and the discharge duration. When the discharge current level is high at 250 mA, the detached flame is observed at shorter discharge duration of 0.8 ms, while when the discharge current is low at 190 mA, detached flame can happen at longer discharge duration of 1.3 ms.

Various discharge current and discharge durations are adopted to initiate the combustion in a single-cylinder engine operating with lean gasoline air mixture. It is shown from the results that a higher discharge current level and longer discharge duration are beneficial for controlling the combustion phasing and improving the operation stability of the engine.
Exhaust Emission Characteristics of Excavator With 6.0 Liter Diesel Engine in Real Work Conditions
Authors: Kwon Sangil , Kim Sung-Woo , Kim Ki-Ho , Seo Youngho , Chon Mun Soo , Kim Daesik , Park Sungwook , Roh Hyun Gu , Suh Hyun Kyu , Park Suhan
Published: January 2019

The purpose of this study is evaluate emission characteristics, such as nitrogen oxides (NOx), hydrocarbon, carbon monoxide, and particulate matter (PM), of excavator with Tier-4f level diesel engine in the real work conditions. The test excavator has an engine power of 124 kW at an engine speed of 1800rpm, and it has various after-treatment devices, such as exhaust gas recirculation (EGR), selective catalytic reduction (SCR), and diesel oxidation catalyst (DOC), to reduce the engine-out emissions. The emissions including carbon monoxide (CO), carbon dioxides (CO2), and NOx, were measured by portable emission measurement system (PEMS). The PEMS device conducted a correlation analysis with the emission bench on the engine dynamometer before being used to measure the real-work to confirm the reliability of the equipment. The tests were carried out in four categories: idling, driving, excavations and flattening.

It revealed that the average power output for each operation mode was higher in the order of flattening, excavation, and drive. On average, those are higher than that for the non-road transient cycle (NRTC) certification mode as 1.5 to 1.9 times. It may be determined that the power output is higher in conditions where there are more boom and bucket movements than the movement of the vehicle itself. In emission analysis, NOx and HC emission in driving mode are higher than other two modes: excavation and flattening. The real time NOx have been low in most test conditions, but large quantities of NOx have been released due to the deactivation of the SCR catalyst during cold start period or immediately after the non-working.
Irregular reflection of spark-generated shock pulses from a rigid surface: Mach-Zehnder interferometry measurements in air
Authors: Karzova Maria M. , Lechat Thomas , Ollivier Sébastien , Dragna Didier , Yuldashev Petr V. , Khokhlova Vera A. , Blanc-Benon Philippe
Published: January 2019

The irregular reflection of weak acoustic shock waves, known as the von Neumann reflection, has been observed experimentally and numerically for spherically diverging waves generated by an electric spark source. Two optical measurement methods are used: a Mach-Zehnder interferometer for measuring pressure waveforms and a Schlieren system for visualizing shock fronts. Pressure waveforms are reconstructed from the light phase difference measured by the interferometer using the inverse Abel transform. In numerical simulations, the axisymmetric Euler equations are solved using finite-difference time-domain methods and the spark source is modeled as an instantaneous energy injection with a Gaussian shape. Waveforms and reflection patterns obtained from the simulations are in good agreement with those measured by the interferometer and the Schlieren methods. The Mach stem formation is observed close to the surface for incident pressures within the range of 800 to 4000 Pa. Similarly, as for strong shocks generated by blasts, it is found that for spherical weak shocks the Mach stem length increases with distance following a parabolic law. This study confirms the occurrence of irregular reflections at acoustic pressure levels and demonstrates the benefits of the Mach-Zehnder interferometer method when microphone measurements cannot be applied.
Physical Activity Trends in Separate Contexts Among South Australian Older Children (10–12 Y) and Early Adolescents (13–15 Y) From 1985 to 2013
Authors: Booth Verity , Rowlands Alex , Dollman James
Published: January 2019

Purpose: To assess trends in South Australian children’s physical activity between 1985 and 2003 and 2013 in the contexts of school active transport, organized sport, physical education, and school break times. Method: The 1985 Australian Health and Fitness Survey was administered in South Australian schools in 2004 (8 schools) and 2013 (9 schools) and was demographically matched to the 10 South Australian schools in the Australian Health and Fitness Survey. Ordinal logistic modeling was used to identify trends, stratified by older children (10–12 y) and early adolescent (13–15 y) subgroups. Results: School active transport generally declined for males and older female children (19 and 20 percentage points per decade, respectively), whereas early adolescent females increased in walking to school (11 percentage points per decade). School sport participation declined for early adolescents, and club sport participation declined in early adolescent females (23 percentage points per decade). Moderate to vigorous physical activity participation during school break times (particularly lunchtime) generally declined (16–26 percentage points per decade). Observed changes in most contexts occurred between 2004 and 2013. Conclusion: There was evidence of context-specific declines in children’s physical activity participation over this time span. Early adolescent females were the subgroup of most concern, experiencing declines in most contexts.
Atlantic Multidecadal Oscillations drive the basin-scale distribution of Atlantic bluefin tuna
Authors: Faillettaz Robin , Beaugrand Grégory , Goberville Eric , Kirby Richard R.
Published: January 2019

The presence of Atlantic bluefin tuna in northern European seas is driven by climate variability and ocean temperature.
Jasmonate promotes artemisinin biosynthesis by activating the TCP14-ORA complex in
Artemisia annua
Authors: Ma Ya-Nan , Xu Dong-Bei , Li Ling , Zhang Fei , Fu Xue-Qing , Shen Qian , Lyu Xue-Ying , Wu Zhang-Kuanyu , Pan Qi-Fang , Shi Pu , Hao Xiao-Long , Yan Ting-Xiang , Chen Ming-Hui , Liu Pin , He Qian , Xie Li-Hui , Zhong Yi-Jun , Tang Yue-Li , Zhao Jing-Ya , Zhang Li-Da , Sun Xiao-Fen , Tang Ke-Xuan
Published: January 2019

JA-induced JAZ8 degradation releases and activates the TCP14-ORA complex in enhancing artemisinin biosynthesis in
Artemisia annua
.
Nonlinear integrated quantum electro-optic circuits
Authors: Luo Kai-Hong , Brauner Sebastian , Eigner Christof , Sharapova Polina R. , Ricken Raimund , Meier Torsten , Herrmann Harald , Silberhorn Christine
Published: January 2019

An integrated chip with quantum state generation, active polarization manipulation, and precise time control is demonstrated.
Autonomously designed free-form 2D DNA origami
Authors: Jun Hyungmin , Zhang Fei , Shepherd Tyson , Ratanalert Sakul , Qi Xiaodong , Yan Hao , Bathe Mark
Published: January 2019

DNA can be used to fabricate any free-form 2D drawing at the nanometer scale.
Monsoon-driven Saharan dust variability over the past 240,000 years
Authors: Skonieczny C. , McGee D. , Winckler G. , Bory A. , Bradtmiller L. I. , Kinsley C. W. , Polissar P. J. , De Pol-Holz R. , Rossignol L. , Malaizé B.
Published: January 2019

Saharan dust emissions over the past 240,000 years vary primarily with summer insolation rather than glacial-interglacial changes.
Anomalous interfacial stress generation during sodium intercalation/extraction in MoS
2
thin-film anodes
Authors: Li Zhi , Jiang Keren , Khan Faheem , Goswami Ankur , Liu Jun , Passian Ali , Thundat Thomas
Published: January 2019

Microcantilevers revealed anomalous interfacial stress generated during sodiation/desodiation in 2D MoS
2
.
Sex differences in GBM revealed by analysis of patient imaging, transcriptome, and survival data
Authors: Yang Wei , Warrington Nicole M. , Taylor Sara J. , Whitmire Paula , Carrasco Eduardo , Singleton Kyle W. , Wu Ningying , Lathia Justin D. , Berens Michael E. , Kim Albert H. , Barnholtz-Sloan Jill S. , Swanson Kristin R. , Luo Jingqin , Rubin Joshua B.
Published: January 2019

Male and female glioblastomas are biologically distinct, and improving outcomes may require sex-specific approaches to treatment.
Protein silencing to stop a “silent killer”
Authors: Jay Steven M.
Published: January 2019

Delivery of a single dose of siRNA to the placenta silences proteins and may help prevent preeclampsia.
Are Standard Dosing Regimens of Ceftriaxone Adapted for Critically Ill Patients with Augmented Creatinine Clearance?
Authors: Ollivier Julien , Carrié Cédric , d’Houdain Nicolas , Djabarouti Sarah , Petit Laurent , Xuereb Fabien , Legeron Rachel , Biais Matthieu , Breilh Dominique
Published: January 2019

The objective of the present study was to determine whether augmented renal clearance (ARC) impacts negatively on ceftriaxone pharmacokinetic (PK)/pharmacodynamic (PD) target attainment in critically ill patients. Over a 9-month period, all critically ill patients treated with ceftriaxone were eligible.
Emergence of a Multidrug-Resistant Hypervirulent Klebsiella pneumoniae Sequence Type 23 Strain with a Rare
bla
CTX-M-24
-Harboring Virulence Plasmid
Authors: Shen Dingxia , Ma Guannan , Li Cuidan , Jia Xinmiao , Qin Chuan , Yang Tingting , Wang Lifeng , Jiang Xiaoyuan , Ding Nan , Zhang Xiuli , Yue Liya , Yin Zhe , Zeng Lijun , Zhao Yongliang , Zhou Dongsheng , Chen Fei
Published: January 2019

Here, we report a multidrug-resistant hypervirulent
Klebsiella pneumoniae
(MDR-HvKP) strain of sequence type 23 (ST23) with a rare hybrid plasmid harboring virulence genes and
bla
CTX-M-24
, and we analyze the genetic basis for relationship between genotypes and MDR-hypervirulence phenotypes. Further analysis indicates that the hybrid plasmid is formed by IS
903D
-mediated intermolecular transposition of the
bla
CTX-M-24
gene into the virulence plasmid.
An Update on Mycobacterial Taxonomy, 2016–2017
Authors: Parrish Nicole
Published: January 2019

This minireview provides an update on recent taxonomic changes for the genus
Mycobacterium
with an emphasis on newly identified species isolated from humans or associated with human disease.
Laboratory Diagnosis of Neonatal Herpes Simplex Virus Infections
Authors: Muller William J. , Zheng Xiaotian
Published: January 2019

Herpes simplex virus (HSV) is a common and often benign infection in humans; although it less commonly affects newborns, infection in this age group can be devastating. Newborns often present with nonspecific clinical findings, making timely and accurate diagnosis of infection critical.
Levels of
Mycoplasma genitalium
Antimicrobial Resistance Differ by Both Region and Gender in the State of Queensland, Australia: Implications for Treatment Guidelines
Authors: Sweeney E. L. , Trembizki E. , Bletchly C. , Bradshaw C. S. , Menon A. , Francis F. , Langton-Lockton J. , Nimmo G. R. , Whiley D. M.
Published: January 2019

Mycoplasma genitalium
is frequently associated with urogenital and rectal infections, with the number of cases of macrolide-resistant and quinolone-resistant
M. genitalium
infection continuing to increase. In this study, we examined the levels of resistance to these two common antibiotic treatments in geographically distinct locations in Queensland, Australia.
In Vitro
and
In Vivo
Characterization of Novel Neuraminidase Substitutions in Influenza A(H1N1)pdm09 Virus Identified Using Laninamivir-Mediated
In Vitro
Selection
Authors: Lloren Khristine Kaith S. , Kwon Jin Jung , Choi Won-Suk , Jeong Ju Hwan , Ahn Su Jeong , Choi Young Ki , Baek Yun Hee , Song Min-Suk
Published: January 2019

With the widespread emergence of NAI-resistant influenza virus strains, continuous monitoring of mutations that confer antiviral resistance is needed. Laninamivir is the most recently approved NAI in several countries; few data exist related to the
in vitro
selection of viral mutations conferring resistance to laninamivir. Thus, we screened and identified substitutions conferring resistance to laninamivir by random mutagenesis of the NA gene of the 2009 pandemic influenza [A(H1N1)pdm09] virus strain followed by deep sequencing of the laninamivir-selected variants. We found several novel substitutions in NA (D199E and P458T) in an A(H1N1)pdm09 background which conferred resistance to NAIs and which had an impact on viral fitness. Our study highlights the importance of continued surveillance for potential antiviral-resistant variants and the development of alternative therapeutics.
Structural Basis of Nanobodies Targeting the Prototype Norovirus
Authors: Ruoff Kerstin , Kilic Turgay , Devant Jessica , Koromyslova Anna , Ringel Alessa , Hempelmann Alexander , Geiss Celina , Graf Juliane , Haas Michelle , Roggenbach Imme , Hansman Grant
Published: January 2019

The discovery of vulnerable regions on norovirus particles is instrumental in the development of effective inhibitors, particularly for GI noroviruses that are genetically diverse. Analysis of these GI.1-specific Nanobodies has shown that similar to GII norovirus particles, the GI particles have vulnerable regions. The only known cofactor region, the HBGA binding pocket, represents the main target for inhibition. With a combination treatment, i.e., the addition of Nano-7 or Nano-94 with 2′FL, the effect of inhibition was increased. Therefore, combination drug treatments might offer a better approach to combat norovirus infections, especially since the GI genotypes are highly diverse and are continually changing the capsid landscape, and few conserved epitopes have so far been identified.
Baculovirus
Per Os
Infectivity Factor Complex: Components and Assembly
Authors: Wang Xi , Shang Yu , Chen Cheng , Liu Shurui , Chang Meng , Zhang Nan , Hu Hengrui , Zhang Fenghua , Zhang Tao , Wang Zhiying , Liu Xijia , Lin Zhe , Deng Fei , Wang Hualin , Zou Zhen , Vlak Just M. , Wang Manli , Hu Zhihong
Published: January 2019

Entry of baculovirus into host insects is mediated by a
per os
infectivity factor (PIF) complex on the envelopes of occlusion-derived viruses (ODVs). Knowledge of the composition and structure of the PIF complex is fundamental to understanding its mode of action. By using multiple approaches, we determined the complete list of proteins (nine) in the PIF complex. In contrast to previous knowledge in the field, the core complex is revised to ∼230 kDa and consists of PIF1 to -3 but not PIF4. Interestingly, our results suggest that the PIF complex is formed in the cytoplasm prior to its transport to the nucleus and subsequent incorporation into ODVs. Only the full complex is resistant to proteolytic degradation in the insect midgut, implying the critical role of the entire complex. These findings provide the baseline for future studies on the ODV entry mechanism mediated by the multiprotein complex.
Inhibition of Ongoing Influenza A Virus Replication Reveals Different Mechanisms of RIG-I Activation
Authors: Liu GuanQun , Lu Yao , Liu Qiang , Zhou Yan
Published: January 2019

The induction of an IFN response by IAV is mainly mediated by the RNA sensor RIG-I. The physiological RIG-I ligands produced during IAV infection are not fully elucidated. Cellular constraints leading to the inhibition of ongoing viral replication likely potentiate an erroneous viral polymerase producing aberrant viral RNA species activating RIG-I. Here, we demonstrate that RIG-I activation during chemical inhibition of continuous viral protein synthesis is attributable to the incoming DI genomes. Erroneous viral replication driven by NP deprivation promotes the generation of RIG-I-activating aberrant viral RNA, but their nature is likely to be distinct from that of DI RNA. Our results thus reveal distinct mechanisms of RIG-I activation by IAV under cellular constraints impeding ongoing viral replication. A better understanding of RIG-I sensing of IAV infection provides insight into the development of novel interventions to combat influenza virus infection.
LXR Alpha Restricts Gammaherpesvirus Reactivation from Latently Infected Peritoneal Cells
Authors: Lange P. T. , Jondle C. N. , Darrah E. J. , Johnson K. E. , Tarakanova V. L.
Published: January 2019

Liver X receptors (LXRs) are nuclear receptors that mediate cholesterol and fatty acid homeostasis. Importantly, as ligand-activated transcription factors, LXRs represent potential targets for the treatment of hypercholesterolemia and atherosclerosis. Here, we demonstrate that LXRα, one of the two LXR isoforms, restricts reactivation of latent gammaherpesvirus from peritoneal cells. As gammaherpesviruses are ubiquitous oncogenic agents, LXRs may represent a targetable host factor for the treatment of poorly controlled gammaherpesvirus infection and associated lymphomagenesis.
Porcine Circovirus 2 Uses a Multitude of Weak Binding Sites To Interact with Heparan Sulfate, and the Interactions Do Not Follow the Symmetry of the Capsid
Authors: Dhindwal Sonali , Avila Bryant , Feng Shanshan , Khayat Reza
Published: January 2019

It has been demonstrated that porcine circovirus 2 (PCV2) attaches to cells via heparan sulfate (HS) and chondroitin sulfate B (CSB) glycosaminoglycans; however, the underlying structural mechanism describing the HS/CSB recognition by PCV2 remains to be explored. We used cryo-electron microscopy with single-particle analysis, symmetry expansion, and focused classification to visualize the interaction between the PCV2 capsid and heparin, an analog of heparan sulfate, to better than 3.6-Å resolution. We observed that the interaction between PCV2 and heparin does not adhere to the icosahedral symmetry of the capsid. To the best of our knowledge, this is the first example where the interaction between heparin and an icosahedral capsid does not follow the symmetry elements of the capsid. Our findings also suggest that anionic polymers, such as dextran sulfate, may act to inhibit PCV2 infection.
Staphylococcus aureus
Impairs the Function of and Kills Human Dendritic Cells via the LukAB Toxin
Authors: Berends Evelien T. M. , Zheng Xuhui , Zwack Erin E. , Ménager Mickaël M. , Cammer Michael , Shopsin Bo , Torres Victor J.
Published: January 2019

Antigen-presenting cells such as dendritic cells (DCs) fulfill an indispensable role in the development of adaptive immunity by producing proinflammatory cytokines and presenting microbial antigens to lymphocytes to trigger a faster, specific, and long-lasting immune response. Here, we studied the effect of
Staphylococcus aureus
toxins on human DCs. We discovered that the leukocidin LukAB hinders the development of adaptive immunity by targeting human DCs. The ability of
S. aureus
to blunt the function of DCs could help explain the high frequency of recurrent
S. aureus
infections. Taken together, the results from this study suggest that therapeutically targeting the
S. aureus
leukocidins may boost effective innate and adaptive immune responses by protecting innate leukocytes, enabling proper antigen presentation and T cell activation.
Burkholderia pseudomallei Δ
tonB
Δ
hcp1
Live Attenuated Vaccine Strain Elicits Full Protective Immunity against Aerosolized Melioidosis Infection
Authors: Khakhum Nittaya , Bharaj Preeti , Myers Julia N. , Tapia Daniel , Kilgore Paul B. , Ross Brittany N. , Walker David H. , Endsley Janice J. , Torres Alfredo G.
Published: January 2019

In recent years, an increasing number of melioidosis cases have been reported in several regions where melioidosis is endemic and in areas where melioidosis had not commonly been diagnosed. Currently, the estimated burden of disease is around 165,000 new cases annually, including 89,000 cases that have fatal outcomes. This life-threatening infectious disease is caused by
B. pseudomallei
, which is classified as a Tier 1 select agent. Due to the high case fatality rate, intrinsic resistance to multiple antibiotic treatments, susceptibility to infection via the aerosol route, and potential use as a bioweapon, we have developed an effective live attenuated PBK001 vaccine capable of protecting against aerosolized melioidosis.
Effect of dietary curcumin and capsaicin on testicular and hepatic oxidant–antioxidant status in rats fed a high-fat diet
Authors: Tanrıkulu-Küçük Sevda , Başaran-Küçükgergin Canan , Seyithanoğlu Muhammed , Doğru-Abbasoğlu Semra , Koçak Hikmet , Beyhan-Özdaş Şule , Öner-İyidoğan Yıldız
Published: January 2019

This study investigated the effects of curcumin and capsaicin on testicular and hepatic oxidant–antioxidant status in rats fed a high-fat diet (HFD). Male Sprague–Dawley rats were divided into 5 groups (8 rats per group). The control group was fed a normal control diet (standard laboratory chow), the HFD group was fed HFD (60% of total calories from fat), the HFD+CUR group received HFD supplemented with curcumin (1.5 g curcumin/kg HFD), the HFD+CAP group was given HFD supplemented with capsaicin (0.15 g capsaicin/kg HFD), and the HFD+CUR+CAP group received HFD supplemented with curcumin and capsaicin for 16 weeks. Hepatic and testicular thiobarbituric acid reactive substances (TBARS), reactive oxygen species (ROS), glutathione (GSH) levels, glutathione transferase activity, and Cu-Zn superoxide dismutase, glutathione peroxidase, and catalase protein expression and enzyme activities were measured. Protein expression was determined by Western blotting. GSH levels and antioxidant enzyme activities were measured with colorimetric methods. HFD slightly increased hepatic and testicular oxidative stress parameters. GSH levels did not change between groups. TBARS and ROS levels were significantly reduced in the HFD+CUR+CAP group compared with the HFD group. Liver and testis antioxidant enzyme activities and expression increased significantly with combined capsaicin and curcumin treatment. Curcumin and capsaicin treatment attenuated testicular and hepatic oxidative stress and enhanced the antioxidant defense system. The combination of capsaicin and curcumin with HFD seems to have some remarkable and beneficial effects on testicular oxidative damage in the fatty liver rat model.
Study of residual stresses in A7N01 aluminum alloy with X-ray diffraction Debye ring analysis
Authors: Zhu Pengfei , Gou Guoqing , Li Zhaofu , Zhu Minhao , Zhu Zhongyin , Ma Chuanping , Gao Wei
Published: January 2019

The welding residual stress has different effects on the mechanical properties of aluminum alloy welded joints, such as size stability, fatigue strength and stress corrosion cracking. Therefore, it is very important to evaluate the welding residual stress accurately. In this paper, the residual stress of A7N01 aluminum alloy welded joints was measured by X-ray diffraction. In contrast to the traditional method, the cos[Formula: see text] method was used in this paper, the results were compared with those obtained by the conventional [Formula: see text] method. In addition, the influence of oscillation unit on the test results of the cos[Formula: see text] method was studied.
Prediction of two-dimensional topography of laser cladding based on neural network
Authors: Hongyu Li , Hui Chen , Ying Wu , Yong Chen , Wei Yi
Published: January 2019

The two-dimensional morphology of the cladding layer has an important influence on the quality of the cladding layer and the crack tendency. Using the powerful nonlinear processing ability of the single hidden layer feedforward neural network, a prediction model between the cladding technological parameters and the two-dimensional morphology of the cladding layer is established. Taking the cladding parameters as the input and the two-dimensional morphology of the cladding as the output, the experimental data is used to train the network to achieve a high-level mapping of the input and output. On this basis, the algorithm of extreme learning machine is used to optimize the single hidden layer feedforward neural network to overcome the problems of slow convergence speed, more network training parameters and easy local convergence in back-propagation algorithm. The results show that the relationship between the cladding process parameters and the two-dimensional morphology of the cladding layer can be roughly reflected by the back-propagation algorithm. However, the prediction results are not stable and the error rate is between 10% and 40%. The neural network optimized by the extreme learning machine is utilized to get a better prediction result. The error rate is 10–20%.
Effect of welding current on arc behavior in tandem GMAW
Authors: Pu Juan , Wu Shan , Hu Qingxian , Wang Yuxin
Published: January 2019

A three-dimensional numerical model of double-arc in tandem gas metal arc welding (GMAW) was established based on the theory of arc physics, momentum equation, energy equation, continuous equation and Maxwell equations. The effects of different welding current on temperature field, velocity field and pressure field on the surface of workpieces were investigated. The results showed that the maximum values of arc temperature, arc plasma velocity and arc pressure on workpieces surface were increased with the increasing welding current. These maximum values occurred at the tip of double-wire. The current density and axial deflection angle of coupling arc were increased following the increasing welding current.
Evaluate welding residual of 6082-T6 aluminum alloy welded plate by using ultrasonic method
Authors: Zhu Zhongyin , Gou Guoqing , Zhang Zhiyi , Ma Chuanping , Gao Wei
Published: January 2019

The residual stress beneath the surface is crucial to the safety of the structures. Neutron Diffraction and Hole-drilling are the two methods being used to measure the inner residual stress. Longitudinal Critically Refracted (LCR) wave transmission that is propagated parallel to surface also can be used for measuring residual stress, but measurements are within an effective depth and need to be further studied. In this paper, the parameters of K are separately tested in WZ, HAZ and BM zone. The welding process of 6082-T6 aluminum alloy welded joints is simulated in SYSWELD, the finite element model has been verified by the X-ray diffraction method. The residual stress value calculated by SYSWELD and the values obtained from the ultrasonic measurement show a good agreement. It is demonstrated that the residual stress of 6082-T6 aluminum alloy welded plate can be evaluated by using the ultrasonic method.
The True Impacts of and Influencing Factors Relating to Carbon Emissions Rights Trading: A Comprehensive Literature Review
Authors: SHI Dan , ZHANG Cheng , ZHOU Bo , YANG Lu
Published: January 2019

As an emissions abatement mechanism focusing on property rights theory and market trading methods, carbon emissions rights trading plays an important role in achieving low-carbon economic development, which has already garnered broad worldwide recognition. In the aftermath of the implementation of an initial, seven-province/city, carbon emissions rights trading pilot project, in 2017 China launched a carbon emissions trading rights market on a national basis. The authors of this paper provide a theoretical basis for research into this trading market’s impacts on energy conservation, reduction of emissions, and on economically sustaining, healthy development, from the following four perspectives: the history of the market’s development, a comparison of carbon reduction mechanisms associated with differing carbon tax levies, the effects of carbon emissions rights trading’s implementation, and the influencing factors on such trading. They systematically summarize, sort out, and evaluate the most recent, related carbon emissions rights trading literature, and then based on this analysis offer up insights regarding possible developments and refinements of future carbon emissions rights trading research.
Profibrotic effect of IL-17A and elevated IL-17RA in idiopathic pulmonary fibrosis and rheumatoid arthritis-associated lung disease support a direct role for IL-17A/IL-17RA in human fibrotic interstitial lung disease
Authors: Zhang Jie , Wang Dan , Wang Lei , Wang Shaohua , Roden Anja C. , Zhao Hao , Li Xiujuan , Prakash Y. S. , Matteson Eric L. , Tschumperlin Daniel J. , Vassallo Robert
Published: January 2019

Interleukin (IL)-17 is a T helper 17 cytokine implicated in the pathogenesis of many autoimmune diseases, including rheumatoid arthritis (RA). Although IL-17A has a well-established role in murine pulmonary fibrosis models, its role in the tissue remodeling and fibrosis occurring in idiopathic pulmonary fibrosis (IPF) and RA-associated interstitial lung disease (RA-ILD) is not very well defined. To address this question, we utilized complimentary studies to determine responsiveness of human normal and pathogenic lung fibroblasts to IL-17A and used lung biopsies acquired from patients with IPF and RA-ILD to determine IL-17A receptor (IL-17RA) expression. Both normal and pathogenic IPF lung fibroblasts express functional IL-17RA and respond to IL-17A stimulation with cell proliferation, generation of extracellular matrix (ECM) proteins, and induction of myofibroblast transdifferentiation. Small interfering RNA (siRNA) silencing of IL-17RA attenuated this fibroblast response to IL-17A on ECM production. These fibroblast responses to IL-17A are dependent on NF-κB-mediated signaling. In addition, inhibiting Janus activated kinase (JAK) 2 by either siRNA or a selective pharmacological inhibitor, AZD1480—but not a JAK1/JAK3 selective inhibitor, tofacitinib—also significantly reduced this IL-17A-induced fibrogenic response. Lung biopsies of RA-ILD patients demonstrate significantly higher IL-17RA expression in areas of fibroblast accumulation and fibrosis, compared with either IPF or normal lung tissue. These observations support a direct role for IL-17A in lung fibrosis that may be particularly relevant in the context of RA-ILD.
Identification of CAV1 and DCN as potential predictive biomarkers for lung adenocarcinoma
Authors: Yan Yuanliang , Xu Zhijie , Qian Long , Zeng Shuangshuang , Zhou Yangying , Chen Xi , Wei Jie , Gong Zhicheng
Published: January 2019

Lung adenocarcinoma (LUAD) is the most common histological form of lung cancer that is clinically diagnosed. The aim of this study is to explore the novel genes associated with LUAD tumorigenesis. Comprehensive bioinformatics analyses of the data were obtained from several publicly available databases, such as the Gene Expression Omnibus, the Human Protein Atlas project, and the Cancer Cell Line Encyclopedia. The clinical relevance of these novel genes in LUAD was further examined by immunohistochemistry. We identified the overlapping differentially expressed genes (DEGs) in five independent microarray data sets from the Gene Expression Omnibus database ( GSE75037 , GSE85716 , GSE85841 , GSE63459 , and GSE32867 ). Using the criteria of |log (fold change)| ≥ 1 and P value <0.05, 167 genes were preliminarily validated as co-DEGs. Protein-protein interaction network analysis indicated that caveolin 1 (CAV1) and decorin (DCN) levels were significantly reduced and that these genes were the most promising predictive biomarkers for the occurrence and prognosis of LUAD. A cell proliferation assay indicated that overexpressed CAV1 and DCN could significantly inhibit the proliferation rate of A549 and H157 cells. Additionally, these two downregulated candidate genes were further verified by immunohistochemistry conducted on a LUAD tissue array and comprehensive bioinformatics analyses, including those using the Oncomine platform and the Cancer Cell Line Encyclopedia. Our study demonstrates low levels of CAV1 and DCN in LUAD. An understanding of their functional roles in LUAD biology would give us important insights that would be useful in further investigations.
Effects of active commuting and leisure-time exercise on appetite in individuals with overweight and obesity
Authors: Quist Jonas Salling , Blond Martin Bæk , Gram Anne Sofie , Steenholt Carina Bjørnskov , Janus Charlotte , Holst Jens Juul , Rehfeld Jens F. , Sjödin Anders , Stallknecht Bente , Rosenkilde Mads
Published: January 2019

Acute exercise is associated with a transient suppression of appetite. The effects of regular exercise on appetite are not well understood. We aimed to determine the effects of active commuting and leisure-time exercise on appetite. One hundred thirty physically inactive women and men (20–45 yr) with overweight and obesity were randomized to 6 mo of habitual lifestyle (CON, n = 18), active commuting (BIKE, n = 35), or leisure-time exercise of moderate [MOD, 50% peak oxygen uptake (V̇o2peak)-reserve, n = 39] or vigorous (VIG, 70% V̇o2peak-reserve, n = 38) intensity. Appetite ratings, acylated ghrelin, cholecystokinin (CCK), glucagon-like peptide-1 (GLP-1), peptide YY (PYY), and glucagon were assessed in the basal state and in response to meal and exercise challenges at baseline and 3 and 6 mo. Ad libitum energy intake was determined during test meals. Data from 90 participants (per protocol) were available, and results are comparisons with CON. At 3 mo, ad libitum energy intake was lower in VIG (−22%, P < 0.01), basal glucagon was lower in BIKE ( P < 0.05) and VIG ( P = 0.01), and postprandial ratings of prospective food consumption were lower in MOD ( P = 0.02) and VIG ( P < 0.001). In VIG, ratings of hunger ( P = 0.01) and prospective food consumption ( P = 0.03) were lower after acute exercise at 3 mo. At 6 mo, basal and postprandial GLP-1 were higher ( P ≤ 0.04) whereas postexercise PYY was lower ( P = 0.03) in VIG and postexercise CCK was lower in BIKE ( P = 0.03). Vigorous-intensity exercise training leads to a transient suppression of energy intake and subjective appetite (3 mo) but a more long-term increase in basal and postprandial GLP-1 (6 mo) in individuals with overweight and obesity.

NEW & NOTEWORTHY This is the first randomized controlled trial, to our knowledge, investigating long-term effects of exercise domain and intensity on subjective and hormonal markers of appetite and ad libitum energy intake in individuals with overweight and obesity. Appetite was assessed in response to meal and exercise challenges at baseline and at 3 and 6 mo. Anorexigenic effects of exercise vary with the duration of intervention and are restricted to regular leisure-time exercise of vigorous intensity in individuals with overweight and obesity.
Fat metabolism and acute resistance exercise in trained women
Authors: Allman Brittany R. , Morrissey Margaret C. , Kim Jeong-Su , Panton Lynn B. , Contreras Robert J. , Hickner Robert C. , Ormsbee Michael J.
Published: January 2019

This study investigated the effect of acute full-body resistance exercise [RE; one set of 10 repetitions at 40% 1 repetition maximum (1RM) and three sets of 10 repetitions at 65% 1RM] on subcutaneous abdominal adipose tissue (SCAAT) lipolysis and whole body substrate oxidation in young (age: 22 ± 1 yr), normal-weight and body fatness (body mass index: 20 ± 1 kg/m2; %body fat: 28.7 ± 1.4%), resistance-trained women. Microdialysis was used to measure SCAAT lipolysis at baseline, mid-RE, post-RE, and 30 min post-RE, and indirect calorimetry was used to measure whole body substrate oxidation at baseline and immediately post-RE in 13 women. Plasma concentrations of glucose, insulin, nonesterified fatty acids (NEFA), glycerol, growth hormone (GH), epinephrine (Epi), and norepinephrine (NE) were measured at baseline, mid-RE, and post-RE. Lipolysis (dialysate glycerol concentration) was elevated post-RE (baseline: 596.7 ± 82.8, post-RE: 961.4 ± 116.3 µM, P = 0.01). Energy expenditure (baseline: 1,560 ± 49; post-RE: 1,756 ± 68 kcal/day; P = 0.02) and fat oxidation (baseline: 5.64 ± 0.24; post-RE: 7.57 ± 0.41 g/h; P = 0.0003) were elevated post-RE. GH (baseline: 513.1 ± 147.4; mid-RE: 1,288.3 ± 83.9; post-RE: 1,522.8 ± 51.1 pg/ml, P = 0.000), Epi (baseline: 23.2 ± 2.7; mid-RE: 92.5 ± 16.6; post-RE: 84.5 ± 21.4 pg/ml, P = 0.000), and NE (baseline: 139.2 ± 13.6; mid-RE: 850.9 ± 155.3; post-RE: 695.3 ± 93.5 pg/ml, P = 0.000) were higher at mid-RE and post-RE. Therefore, one of the potential mechanisms behind RE-induced fat mass changes in resistance-trained women may be in part due to the accumulated effect of transient increases in SCAAT lipolysis, fat oxidation, and energy expenditure, mediated by GH, Epi, and NE release.
Aerodynamic factors affecting rebreathing in infants
Authors: Itzhak Nadav , Greenblatt David
Published: January 2019

The rebreathing of expire air, with high carbon dioxide and low oxygen concentrations, has long been implicated in unexplained Sudden Infant Death Syndrome (SIDS) when infants are placed to sleep in a prone (facedown) position. This study elucidates the effect of the aerodynamic parameters Reynolds number, Strouhal number, and Froude number on the percentage of expired air that is reinspired (rebreathed). A nasal module was designed that served as a simplified geometric representation of infant nostrils and placed above a hard, flat surface. Quantitative and flow visualization experiments were performed to measure rebreathing, using water as the working medium, under conditions of dynamic similarity. Different anatomic (e.g., tidal volume, nostril diameter), physiological (e.g., breathing frequency), and environmental (e.g., temperature, distance from the surface) factors were considered. Increases in Strouhal number (simultaneously faster and shallower breathing) always produced higher rebreathed percentages, because rolled-up vortices in the vicinity of the nostrils had less time to move away by self-induction. Positively and negatively buoyant flows resulted in significant rebreathing. In the latter case, consistent with a warm environment and a high percentage of rebreathed CO2, denser gas pooled in the vicinity of the nostrils. Reynolds numbers below 200 also dramatically increased rebreathing because the expired gas pooled much closer to the nostrils. These results clearly elucidated how the prone position dramatically increases rebreathing by a number of different mechanisms. Furthermore, the results offer plausible explanations of why a high-temperature environment and low birthweight are SIDS risk factors.

NEW & NOTEWORTHY A fundamentally new aerodynamics-based approach to the study of rebreathing of expired air in infants is presented. Rebreathing is implicated in unexplained Sudden Infant Death Syndrome (SIDS) when infants sleep in a prone position. This is the first time that aerodynamic parameters are systematically varied and their effects on rebreathing quantified. The study provides us with a deeper understanding of the effects of breathing frequency, tidal volume (birthweight) and environmental conditions.