bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Volatiles on Soot Based Deposit Layers
Authors: Salvi Ashwin , Hoard John , Bieniek Mitchell , Abarham Mehdi , Styles Dan , Assanis Dionissios
Published: February 2014

The implementation of exhaust gas recirculation (EGR) coolers has recently been a widespread methodology for engine in-cylinder NOX reduction. A common problem with the use of EGR coolers is the tendency for a deposit, or fouling layer to form through thermophoresis. These deposit layers consist of soot and volatiles and reduce the effectiveness of heat exchangers at decreasing exhaust gas outlet temperatures, subsequently increasing engine out NOX emission.

This paper presents results from a novel visualization rig that allows for the development of a deposit layer while providing optical and infrared access. A 24-hour, 379 micron thick deposit layer was developed and characterized with an optical microscope, an infrared camera, and a thermogravimetric analyzer. The in-situ thermal conductivity of the deposit layer was calculated to be 0.047 W/mK. Volatiles from the layer were then evaporated off and the layer reanalyzed. Results suggest that volatile bake-out can significantly alter the thermo-physical properties of the deposit layer and hypotheses are presented as to how.
Tailor Made Biofuels: Effect of Fuel Properties on the Soot Microstructure and Consequences on Particle Filter Regeneration
Authors: Bhardwaj Om Parkash , Lüers Bernhard , Kolbeck Andreas F. , Koerfer Thomas , Kremer Florian , Pischinger Stefan , von Berg Angelika , Roth Georg
Published: February 2014

In recent years a lot of effort has been made to understand the phenomena of Diesel Particulate Filter (DPF) regeneration processes but less attention has been paid to understand the influence of fuel properties on soot reactivity and its consequence on the DPF regeneration behavior.

Within the Cluster of Excellence “Tailor-Made Fuels from Biomass (TMFB)” at RWTH Aachen University, the Institute for Combustion Engines carried out a detailed investigation program to explore the potential of future biofuel candidates for optimized combustion systems. These new biofuels are being developed to realize partially homogeneous low-temperature combustion, in order to reduce the emission and fuel consumption to meet future requirements. The chemical structure of these new fuels may impact the thermal decomposition chemistry and hence the in-cylinder particulate formation conditions. This work fundamentally focusses the influence of fuel properties on particulate matter reactivity and, thereby, the regeneration behavior of the diesel particulate filters (DPF).

The experiments for particulate measurements and analysis were conducted, under constant engine operating conditions, on a EURO 6 compliant High Efficiency Combustion System (HECS) fuelled with petroleum based diesel fuel as baseline and today’s biofuels like FAME and Fischer Tropsch fuels as well as potential biomass derived fuel candidates being researched in TMFB.

Several different methods were used for analysis of mass, composition, structure and spectroscopic parameters of the soot. The graphitic microstructure visible with high resolution transmission electron microscopy (HRTEM) was compared to the results of X-Ray diffraction (XRD), optical light absorption measurement and elementary analysis of samples.

The results indicate that combustion with increasing fuel oxygenation produces decreasing engine-out particulate emissions. The ranking of activation energies of soot oxidation analysis from LGB experiments correspond well with the ranking of the soot physico-chemical properties. In comparison to petroleum based diesel fuel, the reduction of engine out soot emission by a factor of five with the use of the future biomass derived fuel candidate was accompanied by ten times reduction of the soot volume based absorption coefficient and two times reduction of carbon to hydrogen ratio. As a result of it, the activation energy of soot oxidation in DPF reduced by ∼ 10 KJ/mol. The reduced engine out soot emission and increased reactivity of the soot from the future biomass derived fuel candidate could cause a significant reduction of thermal DPF regenerations.
Validation of a Three-Dimensional Internal Nozzle Flow Model Including Automatic Mesh Generation and Cavitation Effects
Authors: Zhao Hongwu , Quan Shaoping , Dai Meizhong , Pomraning Eric , Senecal P. K. , Xue Qingluan , Battistoni Michele , Som Sibendu
Published: February 2014

Fuel injectors often experience cavitation due to regions of extremely low pressure. In this work, a cavitation modeling method is implemented in the CONVERGE CFD code to model the flow in fuel injectors. CONVERGE includes a Cartesian mesh based flow solver. In this solver, a Volume Of Fluid (VOF) method is used to simulate the multiphase flow. The cavitation model is based on a flash-boiling method with rapid heat transfer between the liquid and vapor phases. In this method, a homogeneous relaxation model is used to describe the rate at which the instantaneous quality, the mass fraction of vapor in a two-phase mixture, will tend towards its equilibrium value. The model is first validated with the nozzle flow case of Winklhofer by comparing the mass flow rate with experimentally measured values at different outlet pressures. The cavitation contour shape is also compared with the experimental observations. Flow in the Engine Combustion Network Spray-A nozzle configuration is simulated. The mesh dependency is also studied in this work followed by validation against discharge coefficient data. Finally, calculations of a five-hole injector, including moving needle effects, are compared to experimental measurements.
An Experimental Investigation of Reactivity-Controlled Compression Ignition Combustion in a Single-Cylinder Diesel Engine Using Hydrous Ethanol
Authors: Fang Wei , Kittelson David B. , Northrop William F. , Fang Junhua
Published: February 2014

Dual-fuel reactivity-controlled compression ignition (RCCI) combustion using port injection of a less reactive fuel and early-cycle direct injection of a more reactive fuel has been shown to yield both high thermal efficiency and low NOX and soot emissions over a wide engine operating range. Conventional and alternative fuels such as gasoline, natural gas and E85 as the lower reactivity fuel in RCCI have been studied by many researchers; however, published experimental investigations of hydrous ethanol use in RCCI are scarce. Making greater use of hydrous ethanol in internal combustion engines has the potential to dramatically improve the economics and life cycle carbon dioxide emissions of using bio-ethanol. In this work, an experimental investigation was conducted using 150 proof hydrous ethanol as the low reactivity fuel and commercially-available diesel as the high reactivity fuel in an RCCI combustion mode at various load conditions. A modified single-cylinder diesel engine was used for the experiments. Based on previous studies on RCCI combustion by other researchers, early-cycle split-injection strategy of diesel fuel was used to create an in-cylinder fuel reactivity distribution to maintain high thermal efficiency and low NOX and soot emissions. At each load condition, timing and mass fraction of the first diesel injection was held constant, while timing of the second diesel injection was swept over a range where stable combustion could be maintained. Since hydrous ethanol is highly resistant to auto-ignition and has large heat of vaporization, intake air heating was needed to obtain stable operations of the engine. The study shows that 150 proof hydrous ethanol can be used as the low reactivity fuel in RCCI through 8.6 bar IMEP and with ethanol energy fraction up to 75% while achieving simultaneously low levels of NOX and soot emissions. With increasing engine load, less intake heating is needed and EGR is required to maintain low NOX emissions. Future work will look at stability of hydrous ethanol RCCI at higher engine load.
Preliminary Investigation of Direct Injection Neat n-Butanol in a Diesel Engine
Authors: Yanai Tadanori , Han Xiaoye , Reader Graham T. , Zheng Ming , Tjong Jimi
Published: February 2014

The characteristics of combustion, emissions, and thermal efficiency of a diesel engine with direct injection neat n-butanol were investigated. Tests were conducted on a single cylinder water-cooled four stroke direct injection diesel engine. The engine ran at a load of 6.5 ∼ 8.0 bar IMEP at 1500 rpm engine speed and the injection pressure was controlled to 900 bar. The intake boost pressure, injection timing and EGR rate were adjusted to investigate the engine performance. The test results showed that significantly longer ignition delays were possible when using butanol compared to diesel fuel. Butanol usage generally led to a rapid heat release in a short period, resulting in excessively high pressure rise rate. The pressure rise rate was reduced by retarding the injection timing. The butanol injection timing was limited by misfire and pressure rise rate. Thus, the ignition timing controllable window by injection timing was much narrower than that of diesel. The neat butanol combustion produced near zero soot and very low NOx emissions even at low EGR rate. The tests demonstrated that neat butanol had the potential to achieve ultra-low emissions. However, challenges related to reducing the pressure rise rate and improving the ignition controllability were identified.
Characterization of Methane Number for Producer Gas Blends
Authors: Wise Daniel M. , Olsen Daniel B. , Kim Myoungjin
Published: February 2014

Producer gas, any of a variety of gases generated from biomass gasification, is a renewable gaseous fuel that can be burned in gas engines for power production. Producer gas consists primarily of methane, hydrogen, carbon monoxide, carbon dioxide, and nitrogen. These gas blends can be problematic as a fuel for natural gas engines due to widely varying composition and significantly different fuel properties than natural gas. Characterization of combustion properties of different producer gas compositions is critical if the gas engine is to be operated reliably and at the greatest efficiency possible. A sample space of 35 producer gas blends consisting of distinct percentages of combustible gases (methane, hydrogen, and carbon monoxide) and diluent (carbon dioxide and nitrogen) is created to provide a basis for methane number testing. A test cell is established to mix producer gas blends of desired constituent makeup for consumption in a Waukesha F2 Cooperative Fuel Research (CFR) engine to directly measure methane number for each blend. Additional measurements include combustion pressure statistics, fuel consumption, and power output. Methane number is correlated to combustion pressure statistics and producer gas properties. Methane number measurements are compared with predictions using the software AVL Methane, often employed by engine manufacturers to characterize gaseous fuels. Measured methane number shows a strong correlation to 0–10% and 10–90% burn durations. The predicted methane number values from AVL Methane are significantly different than measured methane number in many cases. The error in the prediction is strongly dependent on the amount of carbon monoxide and hydrogen in the producer gas.
Turbocharging System Design and Performance Analysis of a Marine Diesel Engine
Authors: Cui Yi , Deng Kangyao , Shi Lei
Published: February 2014

The selection of turbocharging systems for 8-cylinder marine diesel engines is difficult due to the existence of scavenge interference between cylinders. The constant pressure and pulse converter turbocharging systems have been used to eliminate the scavenge interference by applying large volume exhaust manifolds or grouped exhaust branches according to the firing order. But, the performance of constant pressure turbocharging system under low speed conditions of propulsion characteristics and transient conditions is poor, because of less available exhaust gas energy. The structure and arrangement of pulse converter turbocharging system is complex, meanwhile, and the performance at high speed and loads is not as good. In this paper, three new turbocharging systems, such as, MIXPC (mixed pulse converter) system, dual-turbocharger system (DTS) and controllable exhaust system (CES) were designed to improve the performance of a marine diesel engine. In the upstream part of MIXPC system, the separated small diameter branch pipes were used to isolate the exhaust gas interference. In the downstream part of MIXPC system, the single main pipe was connected with one entry turbocharger to improve the operation efficiency of the turbocharger. In the DTS, two one-entry turbochargers were used, one of which connected with 4 cylinders by two branch pipes and a mixer. The two cylinders with firing intervals of 270 crank angles were connected with one branch pipe. In the CES, a control valve was used to control the exhaust gas flow. The valve was opened at high speed and load conditions and closed at low speed and load conditions. The steady and transient performance of the three turbocharging systems was analyzed by simulation. The experimental studies were also carried out to compare the performance of the three turbocharging systems. The experimental results showed that the CES had the best fuel efficiency under low speed and load conditions, and the DTS had the best fuel efficiency under high speed and load conditions. Compared with the MIXPC system, the overall brake specific fuel consumption under propeller operating conditions was reduced by 11.3g/kWh with DTS and 5.3g/kWh with CES. But the uniformity of exhaust gas temperatures of cylinder heads was the best for MIXPC system. In general, the DTS was superior considering the structure simplicity and performance of the engine.
In-Cylinder Reaction Chemistry and Kinetics During Negative Valve Overlap Fuel Injection Under Low-Oxygen Conditions
Authors: Kalaskar Vickey B. , Szybist James P. , Splitter Derek A. , Pihl Josh A. , Gao Zhiming , Daw C. Stuart
Published: February 2014

Fuel injection into the negative valve overlap (NVO) period is a common method for controlling combustion phasing in homogeneous charge compression ignition (HCCI) as well as other forms of advanced combustion. During this event, at least a portion of the fuel hydrocarbons can be converted to products containing significant levels of H2 and CO, as well as other short chain hydrocarbons by means of thermal cracking, watergas shift, and partial oxidation reactions, depending on the availability of oxygen and the time-temperature-pressure history. The resulting products alter the autoignition properties of the combined fuel mixture for HCCI. Fuel-rich chemistry in a partial oxidation environment is also relevant to other high efficiency engine concepts (e.g., the dedicated EGR (D-EGR) concept from SWRI). In this study, we used a unique 6-stroke engine cycle to experimentally investigate the chemistry of a range of fuels injected during NVO under low oxygen conditions. Fuels investigated included iso-octane, iso-butanol, ethanol, and methanol. Products from NVO chemistry were highly dependent on fuel type and injection timing, with iso-octane producing less than 1.5% hydrogen and methanol producing more than 8%. We compare the experimental trends with CHEMKIN (single zone, 0-D model) predictions using multiple kinetic mechanisms available in the current literature. Our primary conclusion is that the kinetic mechanisms investigated are unable to accurately predict the magnitude and trends of major species we observed.
A Comparison of Valving Strategies Appropriate for Multi-Mode Combustion Within a Downsized Boosted Automotive Engine: Part A — High Load Operation Within the SI Combustion Regime
Authors: Shingne Prasad S. , Gerow Matthew S. , Triantopoulos Vassilis , Bohac Stanislav V. , Martz Jason B.
Published: February 2014

As future downsized boosted engines may employ multiple combustion modes, the goal of the current work is the definition of valving strategies appropriate for moderate to high load spark ignition (SI) combustion and for spark assisted compression ignition (SACI) combustion at low to moderate loads for an engine with variable valve timing capability and fixed camshaft profiles. The dilution and unburned gas temperature requirements for SACI combustion can be markedly different from those of SI; therefore it is important to ensure that a given valving strategy is appropriate for operation within both regimes. This paper compares one dimensional (1D) thermodynamic simulations of rated engine operation with positive valve overlap (PVO) and a baseline negative valve overlap (NVO) camshaft design in a boosted automotive engine with variable valve timing capability. Several peak lifts and valve open durations are investigated to guide the down-selection of camshaft profiles for further evaluation under SACI conditions in a companion paper.

While the results of this study are engine specific, rated performance predictions show that the duration of both the intake and exhaust camshafts significantly impacts the ability to achieve high load operation. While it was noted that the flow through the exhaust valve chokes for the majority of the exhaust stroke for peak exhaust lifts less than 8 mm, the engine rating could be achieved with peak intake lifts as low as 4 mm. Therefore, camshafts with peak lifts of 8/4 mm exhaust/intake were down selected to facilitate multimode combustion operation with high levels of PVO. Analysis of high load operation with the down-selected camshafts indicates that peak unburned gas temperatures remain low enough to mitigate end-gas knock, while other variables such as peak cylinder pressure, turbine inlet temperature and turbocharger speed are all predicted to be within acceptable limits.
RCCI Operation With PFI of n-Butanol and DI of Biodiesel Compared With DI of Binary Mixtures of n-Butanol and Biodiesel
Authors: Soloiu Valentin , Duggan Marvin , Weaver Jabeous , Vlcek Brian , Harp Spencer , Molina Gustavo
Published: February 2014

In this study the Reactive Controlled Combustion Ignition (RCCI) obtained by early port fuel injection (PFI) of n-butanol and direct injection (DI) of biodiesel were compared with in cylinder direct injected binary mixture of n-butanol and biodiesel with the same mass ratio of 3:1 in both fuelling strategies. The combustion and emissions characteristics were investigated at 5 bars IMEP at 1400 rpm. The ignition for DI of n-butanol-biodiesel binary blends showed a delay by approximately 7.5°CAD compared with the PFI case. For the binary mixture, n-butanol-biodiesel, the combustion pressure has decreased by 50% compared to the PFI of butanol. The maximum in cylinder gas temperature decreased by 100K for the n-butanol-biodiesel mixture versus ULSD#2 and has also experienced a 10° CAD delay. The premixed charge combustion has been split into two regions of high temperature heat release, an early one BTDC, and a second stage, ATDC for the PFI strategy. Increasing the load to 7.5 bars IMEP, heavy knock occurred for the PFI case. The soot emissions showed a 90% decrease with n-butanol injection PFI and by 98% reduction for DI of n-butanol binary mixture with the biodiesel, while the NOx emissions were reduced by 40% in both cases. The aldehyde emissions exhibited a significant 95% decrease for the n-butanol-biodiesel binary mixture compared with the n-butanol PFI. The mechanical efficiency at 80% and thermal efficiency and 38% were found similar, for both fuelling strategies.

The results of this work suggest that the DI of n-butanol-biodiesel binary mixtures is more effective in reducing emissions than PFI of n-butanol combined with DI of biodiesel and also less likely to produce knock.
Heusler nanoparticles for spintronics and ferromagnetic shape memory alloys
Authors: Wang Changhai , Meyer Judith , Teichert Niclas , Auge Alexander , Rausch Elisabeth , Balke Benjamin , Hütten Andreas , Fecher Gerhard H. , Felser Claudia
Published: February 2014

Heusler nanoparticles emerge as a new class of multifunctional materials. In this critical review, the latest progress in studies on Heusler nanoparticles is summarized. The authors discuss their structural and physical properties interesting for research fields such as spintronics and ferromagnetic shape memory alloys. As a young research field, the majority of studies on Heusler nanoparticles focus on their synthesis, structure, and magnetic characterizations. Important issues such as size dependent structure, phase transition, magnetic, and spin-related properties are still open. Further investigations are needed to verify the technical significance of Heusler nanoparticles for practical applications such as data storage, magnetic sensors, and microactuators.
Women Outperform Men in Ultradistance Swimming: The Manhattan Island Marathon Swim from 1983 to 2013
Authors: Knechtle Beat , Rosemann Thomas , Lepers Romuald , Rüst Christoph Alexander
Published: February 2014

Purpose:

Recent studies suggested that women’s and men’s ultraswim performances may be similar for distances of ~35 km. The current study investigated both the gender difference and the age of peak ultraswim performance between 1983 and 2013 at the 46-km Manhattan Island Marathon Swim with water temperatures <20°C.

Methods:

Changes in race times and gender difference in 551 male and 237 female finishers were investigated using linear-, nonlinear-, and hierarchical multilevel-regression analyses.

Results:

The top 10 race times ever were significantly (P < .0001) lower for women (371 ± 11 min) than for men (424 ± 9 min). Race times of the annual fastest and annual 3 fastest women and men did not differ between genders and remained stable across years. The age of the annual 3 fastest swimmers increased from 28 ± 4 y (1983) to 38 ± 6 y (2013; r2 = .06, P = .03) in women and from 23 ± 4 y (1984) to 42 ± 8 y (2013; r2 = .19, P < .0001) in men.

Conclusions:

The best women were ~12–14% faster than the best men in a 46-km open-water ultradistance race with temperatures <20°C. The maturity of ultradistance swimmers has changed during the last decades, with the fastest swimmers becoming older across the years.
Instruments to Assess Mobility Limitation in Community-Dwelling Older Adults: A Systematic Review
Authors: Chung Jane , Demiris George , Thompson Hilaire J.
Published: February 2014

Mobility is critical in maintaining independence in older adults. This study aims to systematically review the scientific literature to identify measures of mobility limitation for community-dwelling older adults. A systematic search of PubMed, CINAHL, and psycINFO, using the search terms “mobility limitation”, “mobility disability”, and “mobility difficulty” yielded 1,847 articles from 1990 to 2012; a final selection of 103 articles was used for the present manuscript. Tools to measure mobility were found to be either self-report or performance-based instruments. Commonly measured constructs of mobility included walking, climbing stairs, and lower extremity function. There was heterogeneity in ways of defining and measuring mobility limitation in older adults living in the community. Given the lack of consistency in assessment tools for mobility, a clear understanding and standardization of instruments are required for comparison across studies and for better understanding indicators and outcomes of mobility limitation in community-dwelling older adults.
Super-Eddington Mechanical Power of an Accreting Black Hole in M83
Authors: Soria R. , Long K. S. , Blair W. P. , Godfrey L. , Kuntz K. D. , Lenc E. , Stockdale C. , Winkler P. F.
Published: February 2014

There Goes the Neighborhood

A mass-accreting black hole in steady-state cannot produce more radiative energy than its gravity can counterbalance, achieving what is known as the Eddington limit. However, mass accretion can also be converted into kinetic energy via mechanical outflow. Using x-ray observations,

Soria
et al.

(p.
1330
, published online 27 February; see the Perspective by

King

and the cover) identified a compact shock-ionized radio/optical nebula in spiral galaxy M83, powered by a black hole, inferred that the black hole emits a spherical wind that exceeds the Eddington limit tenfold and succeeded in estimating it's mass in the range of 5 to 15 solar masses. It is possible that rapidly accreting black holes have greater influence on their host galaxy than once appreciated.
Highly Crystalline Multimetallic Nanoframes with Three-Dimensional Electrocatalytic Surfaces
Authors: Chen Chen , Kang Yijin , Huo Ziyang , Zhu Zhongwei , Huang Wenyu , Xin Huolin L. , Snyder Joshua D. , Li Dongguo , Herron Jeffrey A. , Mavrikakis Manos , Chi Miaofang , More Karren L. , Li Yadong , Markovic Nenad M. , Somorjai Gabor A. , Yang Peidong , Stamenkovic Vojislav R.
Published: February 2014

Giving Electrocatalysts an Edge

Platinum (Pt) is an excellent catalyst for the oxygen-reduction reaction (ORR) in fuel cells and electrolyzers, but it is too expensive and scarce for widespread deployment, even when dispersed as Pt nanoparticles on carbon electrode supports (Pt/C). Alternatively,

Chen
et al.

(p.
1339
, published online 27 February; see the Perspective by

Greer

) made highly active ORR catalysts by dissolving away the interior of rhombic dodecahedral PtNi
3
nanocrystals to leave Pt-rich Pt
3
Ni edges. These nanoframe catalysts are durable—remaining active after 10,000 rounds of voltage cycling—and are far more active than Pt/C.
Functional Analysis Using Whole-Genome Sequencing of a Drug-Sensitive Mycobacterium tuberculosis Strain from Peru
Authors: Tarazona D. , Borda V. , Galarza M. , Agapito J. C. , Guio H.
Published: February 2014

We report the whole-genome sequence of a Latin American-Mediterranean (LAM) lineage drug-sensitive
Mycobacterium tuberculosis
strain from Peru, INS-SEN. The functional analysis revealed more mutations in secondary metabolite biosynthesis, transport, and catabolism (clusters of orthologous groups [COG] category Q) than for other LAM-sensitive strains. This study contributes to the understanding of the genomic diversity of drug-sensitive
M. tuberculosis
.
Insight into the Draft Genome Sequence of Human Isolate Lactobacillus rhamnosus LR231, a Bacterium with Probiotic Potential
Authors: Ambalam Padma , Pithva Sheetal , Kothari Charmy , Kothari Ramesh , Parmar Nidhi , Nathani Neelam M. , Koringa Prakash G. , Joshi Chaitanya G. , Dave J. M. , Vyas B. R. M.
Published: February 2014

Lactobacillus rhamnosus
strain LR231 was isolated from the feces of healthy human subjects. It is observed to be a potential probiotic strain, having a broad spectrum of antimicrobial activity against a wide range of human pathogens and food pathogens. Here, we provide the 2.59-Mb draft genome sequence of
L. rhamnosus
LR231.
Genetic polymorphism ofNFKB1andNFKBIAgenes and liver cancer risk: a nested case–control study in Shanghai, China
Authors: Gao Jing , Xu Hong-Li , Gao Shan , Zhang Wei , Tan Yu-Ting , Rothman Nat , Purdue Mark , Gao Yu-Tang , Zheng Wei , Shu Xiao-Ou , Xiang Yong-Bing
Published: February 2014

Objectives

Genetic variations of nuclear factor-κB (NF-κB) signalling pathway were found to be associated with inflammatory diseases and several malignancies. However, little is known about NF-κB pathway gene polymorphisms and susceptibility of liver cancer. The aim of this study was to investigate whether genetic variants ofNFKB1andNFKBIAwere associated with risk of liver cancer in a Chinese population.

Design

The study was designed as a nested case–control study within two prospective cohorts (the Shanghai Women's Health Study, SWHS, 1996–2000 and the Shanghai Men's Health Study, SMHS, 2002–2006).

Settings

This population-based study was conducted in urban Shanghai, China.

Participants

A total of 217 incident liver cancer cases diagnosed through 31 December 2009 and 427 healthy controls matched by sex, age at baseline (±2 years) and date (±30 days) of sample collection were included in the study.

Primary and secondary outcome measures

Genetic polymorphisms ofNFKB1andNFKBIAwere determined blindly by TaqMan single-nucleotide polymorphism (SNP) genotyping assay. OR and its 95% CIs were estimated by an unconditional logistic regression model to measure the association between selected SNPs and the risk of liver cancer.

Results

After adjusted for potential confounding factors, rs28362491 ins/del or del/del genotypes were associated with higher risk of liver cancer with an adjusted OR 1.54 (95% CI 1.04 to 2.28). rs230496 AG and GG genotypes were also noted with higher risk of liver cancer with an adjusted OR 1.53 (95% CI 1.03 to 2.26). Haplotype analysis indicated that carriers of theNFKB1GA and AA (rs230525-rs230530) haplotypes had higher risk of liver cancer under an additive model. No association was observed betweenNFKBIAvariants and risk of live cancer.

Conclusions

Our results suggest that genetic variants ofNFKB1influence liver cancer susceptibility in Chinese population, although replication in other studies is needed.
Adverse socioeconomic position during the life course is associated with multiple sclerosis
Authors: Briggs Farren B S , Acuña Brigid S , Shen Ling , Bellesis Kalliope H , Ramsay Patricia P , Quach Hong , Bernstein Allan , Schaefer Catherine , Barcellos Lisa F
Published: February 2014

Background

Adverse socioeconomic position (SEP) in childhood and adulthood is associated with a proinflammatory phenotype, and therefore an important exposure to consider for multiple sclerosis (MS), a complex neuroinflammatory autoimmune disease. The objective was to determine whether SEP over the life course confers increased susceptibility to MS.

Methods

1643 white, non-Hispanic MS case and control members recruited from the Kaiser Permanente Medical Care Plan, Northern California Region, for which comprehensive genetic, clinical and environmental exposure data have been collected were studied. Logistic regression models investigated measures of childhood and adulthood SEP, and accounted for effects due to established MS risk factors, includingHLA-DRB1*15:01allele carrier status, smoking history, history of infectious mononucleosis, family history of MS and body size.

Results

Multiple measures of childhood and adulthood SEP were significantly associated with risk of MS, includingparents rentingversusowning a home at age 10: OR=1.48, 95% CI 1.09 to 2.02, p=0.013;less than a college educationversusat least a college education based on parental household: OR=1.28, 95% CI 1.01 to 1.63, p=0.041;lowversushigh life course SEP: OR=1.50, 95% CI 1.09 to 2.05, p=0.012; andlowversushigh social mobility: OR=1.74, 95% CI 1.27 to 2.39, p=5.7×10−4.

Conclusions

Results derived from a population-representative case–control study provide support for the role of adverse SEP in MS susceptibility and add to the growing evidence linking lower SEP to poorer health outcomes. Both genetic and environmental contributions to chronic conditions are important and must be characterised to fully understand MS aetiology.
Prevalence of dog erythrocyte antigen 1.1 in galgos (Spanish greyhounds)
Authors: Mesa‐Sanchez I. , Ruiz de Gopegui‐Fernández R. , Granados‐Machuca M. M. , Galan‐Rodriguez A.
Published: February 2014

Dog erythrocyte antigen (DEA) 1.1 is the most clinically important blood group in dogs, as negative recipients for this group may develop a life‐threatening acute haemolytic transfusion reaction if they receive several DEA 1.1 positive blood transfusions. Due to their physical features, galgos are frequently used as blood donors in clinical practice, however, there are no published data regarding the prevalence of DEA 1.1 in this breed. Expression of DEA 1.1 was determined in 118 galgos and 88 dogs of other breeds being screened as potential blood donors, using an immunochromatographic cartridge typing kit (Quick Test DEA 1.1, Alvedia, Lyon, France). Of the total dogs, 53.4per cent (110/206) were positive for DEA 1.1. The prevalence of DEA 1.1 positive blood among our population of galgos and other‐breed dogs were 51.7 per cent (61/118) and 55.7 per cent (49/88), respectively. Potential risk of sensitisation in a recipient of other breed following non‐typed blood transfusion using blood from galgos was 22.9 per cent. Due to the clinical significance of DEA 1.1 and the high prevalence of this blood group in galgos of Spain, we strongly recommend blood‐typing for this group before administering any blood transfusion using galgos as donors, as with transfusions from other commonly used breeds.
Microbeam methods for the analysis of glass in fine-grained tephra deposits: a SMART perspective on current and future trends
Authors: Pearce Nicholas J. G. , Abbott Peter M. , Martin-Jones Catherine
Published: February 2014

Correlation of tephra deposits frequently relies on the analysis of glass shards separated from their host. Small shards from distal deposits (marine-, ice- or lake-cores, peat bogs) are difficult to analyse. Here current methods for glass shard analysis from (particularly) marine tephra deposits are reviewed. These methods apply equally to other distal deposits, where linking repositories of climatic information is central to many research programmes. Electron probe microanalysis is used widely to determine the major element compositions of volcanic glass. However, electron beam irradiation causes permanent damage to glass, especially hydrated or silica- and alkali-rich compositions. Recent developments have shown that reliable data is obtained with beam diameters >3 µm on basaltic or moderately hydrated rhyolitic glass, provided low electron beam current densities are used. For robust correlation of tephra deposits from different environments, it is recommended that analytical data are normalized to an anhydrous basis. Glass trace element analysis is commonly performed by laser ablation inductively coupled plasma mass spectrometry, which determines approx. 30 elements at <1 ppm from ablation craters 10 µm diameter, and although element fractionation occurs, it can be corrected. Recent developments in both methods should facilitate analysis of smaller, more distal material, expanding the geographical range over which reliable tephra correlations can be achieved.
Evolution of shallow and deep structures along the Maipo–Tunuyán transect (33°40′S): from the Pacific coast to the Andean foreland
Authors: Giambiagi Laura , Tassara Andrés , Mescua José , Tunik Maisa , Alvarez Pamela P. , Godoy Estanislao , Hoke Greg , Pinto Luisa , Spagnotto Silvana , Porras Hernán , Tapia Felipe , Jara Pamela , Bechis Florencia , García Víctor H. , Suriano Julieta , Moreiras Stella Maris , Pagano Sebastían D.
Published: February 2014

We propose an integrated kinematic model with mechanical constrains of the Maipo–Tunuyán transect (33°40′S) across the Andes. The model describes the relation between horizontal shortening, uplift, crustal thickening and activity of the magmatic arc, while accounting for the main deep processes that have shaped the Andes since Early Miocene time. We construct a conceptual model of the mechanical interplay between deep and shallow deformational processes, which considers a locked subduction interface cyclically released during megathrust earthquakes. During the coupling phase, long-term deformation is confined to the thermally and mechanically weakened Andean strip, where plastic deformation is achieved by movement along a main décollement located at the base of the upper brittle crust. The model proposes a passive surface uplift in the Coastal Range as the master décollement decreases its slip eastwards, transferring shortening to a broad area above a theoretical point S where the master detachment touches the Moho horizon. When the crustal root achieves its actual thickness of 50 km between 12 and 10 Ma, it resists further thickening and gravity-driven forces and thrusting shifts eastwards into the lowlands achieving a total Miocene–Holocene shortening of 71 km.
Opportunities and Progress
Authors: Litchfield John H.
Published: February 2014

In this review, I cover my professional experiences in food science and technology and related areas of applied and industrial microbiology over the span of my career. It emphasizes opportunities and technological problems that I encountered together with my progress in follow-up development of products and processes.
Skeletal muscle capillary density and microvascular function are compromised with aging and type 2 diabetes
Authors: Groen Bart B. L. , Hamer Henrike M. , Snijders Tim , van Kranenburg Janneau , Frijns Dionne , Vink Hans , van Loon Luc J. C.
Published: February 2014

Adequate muscle perfusion is required for the maintenance of skeletal muscle mass. Impairments in microvascular structure and/or function with aging and type 2 diabetes have been associated with the progressive loss of skeletal muscle mass. Our objective was to compare muscle fiber type specific capillary density and endothelial function between healthy young men, healthy older men, and age-matched type 2 diabetes patients. Fifteen healthy young men (24 ± 1 yr), 15 healthy older men (70 ± 2 yr), and 15 age-matched type 2 diabetes patients (70 ± 1 yr) were selected to participate in the present study. Whole body insulin sensitivity, muscle fiber type specific capillary density, sublingual microvascular density, and dimension of the erythrocyte-perfused boundary region were assessed to evaluate the impact of aging and/or type 2 diabetes on microvascular structure and function. Whole body insulin sensitivity was significantly lower at a more advanced age, with lowest values reported in the type 2 diabetic patients. In line, skeletal muscle capillary contacts were much lower in the older and older type 2 diabetic patients when compared with the young. Sidestream darkfield imaging showed a significantly greater thickness of the erythrocyte perfused boundary region in the type 2 diabetic patients compared with the young. Skeletal muscle capillary density is reduced with aging and type 2 diabetes and accompanied by impairments in endothelial glycocalyx function, which is indicative of compromised vascular function.
Delay in Nephrectomy and Cancer Control Outcomes in Elderly Patients with Small Renal Masses
Authors: Becker Andreas , Roghmann Florian , Ravi Praful , Tian Zhe , Kluth Luis Alexander , Gandaglia Giorgio , Noldus Joachim , Dahlem Roland , Schlomm Thorsten , Graefen Markus , Karakiewicz Pierre I. , Trinh Quoc-Dien , Sun Maxine
Published: February 2014

Objective: To examine the impact of nephrectomy delay on the survival of patients with small renal masses. Methods: Relying on the Surveillance, Epidemiology, and End Results Medicare-linked database, 6,237 patients with pT1a renal cell carcinoma who underwent radical or partial nephrectomy were identified (1988-2005). Nephrectomy delay was dichotomized as ≤3 vs. >3 months. Uni- and multivariate Cox regression analyses tested the effect of delayed nephrectomy on cancer-specific mortality (CSM). In sub-analyses, various other time from diagnosis to nephrectomy cut-offs were modelled: (a) ≤1 vs. >1 month, (b) ≤2 vs. >2 months, (c) ≤4 vs. >4 months, (d) ≤6 vs. >6 months, (e) ≤12 vs. >12 months or (f) continuously coded. Results: In univariate analyses, nephrectomy delay >3 months was associated with a higher risk of CSM (hazard ratio [HR]: 2.07; 95% confidence interval [CI]: 1.58-2.72; p < 0.001). However, after multivariate adjustment, a nephrectomy delay >3 months was not significantly associated with a higher risk of CSM (HR: 1.33; 95% CI: 0.96-1.86; p = 0.09). The lack of a relationship between nephrectomy delay and CSM after multivariate adjustment persisted even in various sub-analyses of other categorizations for nephrectomy delay. Conclusions: In the case of eventual nephrectomy delay among patients with small renal masses, CSM is unaffected.
Swiss Quality and Outcomes Framework: Quality Indicators for Diabetes Management in Swiss Primary Care Based on Electronic Medical Records
Authors: Djalali S. , Frei A. , Tandjung R. , Baltensperger A. , Rosemann T.
Published: February 2014

Background: Most industrialized countries are faced with a growing population of patients with chronic diseases and multimorbidity. Evidence performance gaps have been recognized in the treatment of this vulnerable patient group. In England, the Quality and Outcomes Framework (QOF) - based on incentivized quality indicators - has been established to narrow the gap. Objective: We evaluated to what extent clinical data, extracted from electronic medical records (EMRs) of Swiss general practitioners, can be used as quality indicators in terms of a Swiss Quality and Outcomes Framework (SQOF) for diabetes care adopted from the QOF of the UK National Health Service (NHS). Methods: We searched the FIRE database (Family Medicine ICPC Research Using Electronic Medical Records) for patients suffering from diabetes type 1 or type 2. Eligible data were matched with the diabetes indicator set of the NHS QOF and compared with the results in England. Results: A total of 11 out of 17 diabetes indicators could be adopted for the SQOF; 46 practices with 1,781 diabetes patients were included. The practices fulfilled the SQOF diabetes indicator set with 46.9% overall, with highest compliance for blood pressure measurements (97.8% of all practices) and lowest compliance for influenza immunization (45.7%). Our study practices showed higher variation across all indicators and between practices compared to England, but lacking structured data limited calculation of scores and comparability. Conclusions: Our results show that it is technically feasible to establish a diabetes QOF in Swiss primary care based on EMRs. However, a high amount of missing data made it impossible to evaluate the actual quality of care. For a nationwide introduction, standards for electronic medical documentation and EMR use need to be set. It should also be acknowledged that important dimensions of suffering from one or more chronic diseases such as health-related quality of life are not reflected within a system focusing only on somatic aspects of a disease.
Oral Terbinafine and Itraconazole Treatments against Dermatophytes Appear Not to Favor the Establishment of Fusarium spp. in Nail
Authors: Verrier Julie , Bontems Olympia , Baudraz-Rosselet Florence , Monod Michel
Published: February 2014

Background: Fusarium onychomycoses are weakly responsive or unresponsive to standard onychomycosis treatments with oral terbinafine and itraconazole. Objective: To examine whether the use of terbinafine and itraconazole, which are highly effective in fighting Trichophyton onychomycoses, could be a cause of the high incidence of Fusarium nail infections. Methods: Polymerase chain reaction methods were used to detect both Fusarium spp. and Trichophyton spp. in nails of patients who had either received treatment previously or not. Results: No significant microbiological differences were found between treated and untreated patients. In 24 of 79 cases (30%), Fusarium spp. was detected in samples of patients having had no previous antifungal therapy and when Trichophyton spp. grew in culture. Conclusion: Oral terbinafine and itraconazole treatments do not appear to favor the establishment of Fusarium spp. in onychomycosis.
Mental Health and Multimorbidity: Psychosocial Adjustment as an Important Process for Quality of Life
Authors: Schulze Thekla , Maercker Andreas , Horn Andrea B.
Published: February 2014

Background: Multimorbidity (the co-occurrence of two or more chronic diseases) can be seen as a prototypical situation in which psychosocial adjustment is required. Even though most patients adapt successfully, a significant number of individuals show adaptation problems and develop additional mental health problems. Objective: For this reason, this article focuses on the importance of psychosocial adaptation as a core process in the context of quality of life. Results: Important findings pointing at the association between multimorbidity and mental health are summarized, and the stress-response perspective on psychosocial adjustment is introduced. Furthermore, cognitive-affective processing of the disease (in the context of illness perceptions) and interpersonal emotion regulation are presented as relevant examples for processes involved in psychological adaptation to multimorbidity. As an intervention possibility, expressive writing is given as a feasible example. Conclusion: Viewing adjustment problems to multimorbidity from a stress-response perspective offers a framework for a deeper understanding of core processes regarding multimorbidity and quality of life that is not only important for research but also for clinical practice. This article ends with a general summary and an outlook on clinical implications of the introduced stress-response concept of adjustment to multimorbidity.
Multidomain Engagement and Self-Reported Psychosomatic Symptoms in Middle-Aged Women and Men
Authors: Freund Alexandra M. , Knecht Michaela , Wiese Bettina S.
Published: February 2014

Background: Multimorbidity can be operationalized as the presence of multiple psychosomatic symptoms and has been shown to be detrimental to the quality of life across the life span. Middle-aged adults are generally engaged in multiple life domains simultaneously. This is one of the developmental challenges of middle adulthood as it can lead to conflict between the demands of different domains and, in turn, contribute to multiple psychosomatic symptoms, thereby diminishing the quality of life. This may be particularly true for women. Facilitation between life domains may serve to reduce the number of psychosomatic symptoms. However, this subject has been largely neglected in the literature. Objective: We aimed to close this gap by investigating the influence of conflict and facilitation between life domains (work, family, leisure) on self-reported psychosomatic symptoms in middle-aged women and men. Methods: Life domain conflict/facilitation and psychosomatic symptoms were assessed via self-report in a cross-sectional study with 277 adults aged 30-55 years (mean = 41.70, SD = 7.2; 56.7% women) who all worked at least 30 h/week and lived with their partner or family. Results: In line with our hypothesis, women reported more psychosomatic symptoms when they experienced conflict between life domains. However, contrary to expectation, they did not profit more from facilitation than men and, at low levels of facilitation, women even reported more psychosomatic symptoms than men. In men, there was no association between life domain conflict/facilitation and psychosomatic symptoms. The results were robust when statistically controlling for neuroticism. Conclusions: Engagement in multiple life domains influences the frequency of psychosomatic symptoms in women, but not in men: women suffer more and profit less than men from combining work, family and leisure.